Science.gov

Sample records for radiation-induced brachial plexopathy

  1. Brachial plexopathy

    MedlinePlus

    Neuropathy - brachial plexus; Brachial plexus dysfunction; Parsonage Turner syndrome; Pancoast syndrome ... dysfunction (brachial plexopathy) is a form of peripheral neuropathy . It occurs when there is damage to the ...

  2. 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

  3. 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.

  4. Early transient radiation-induced brachial plexopathy in locally advanced head and neck cancer

    PubMed Central

    Etiz, Durmus

    2016-01-01

    Aim of the study Early transient brachial plexopathy following radiotherapy (RT) in patients with head and neck cancer may be underreported and associated with a dose-response. Our purpose was to determine the incidence of early transient radiation-ınduced brachial plexopathy (RIBP) in patients receiving primary RT (± chemotherapy) for locally advanced head and neck cancer (HNC). Material and methods Twenty-seven locally advanced HNC patients who have no finding of brachial plexopathy at the diagnosis were evaluated 3 times by a specifically developed 13-item questionnaire for determining early transient RIBP. The 54 brachial plexus in 27 patients were delineated and dose volume histograms were calculated. Results Median follow-up period was 28 (range: 15–40) months. The mean BP volume was 7.9 ±3.6 cm3, and the mean and maximum doses to the BP were 45.3 (range: 32.3–59.3) Gy, and 59.4 (range: 41.4–70.3) Gy, respectively. Maximum dose to the BP was ≥ 70 Gy only in 2 nasopharyngeal cancer patients. Two (7%) early transient RIBP were reported at 7th and 8th month after RT under maximum 67.17 and 55.37 Gy, and mean 52.95 and 38.60 Gy RT doses. Conclusions Two (7%) early RIBP were seen in the patient group, although brachial plexus maximum doses were ≥ 66 Gy in 75% of patients. PMID:27095943

  5. West Nile virus-associated brachial plexopathy.

    PubMed

    Chahil, Mandeep; Nguyen, Thy Phuong

    2016-01-01

    West Nile virus (WNV) is the most frequent cause of arbovirus infection in the USA. Only 20% of infected individuals are symptomatic. Less than 1% of symptomatic individuals display West Nile neuroinvasive disease. We report a rare case of WNV-associated brachial plexopathy in a young immunocompetent individual, without cerebrospinal fluid pleocytosis or encephalitis. Additionally, there was subjective and objective improvement after high-dose corticosteroids. This case adds to the clinical spectrum of WNV neuroinvasive disease. The literature regarding immunomodulatory treatment and WNV is reviewed. PMID:27030459

  6. Upper trunk brachial plexopathy. The stinger syndrome.

    PubMed

    Markey, K L; Di Benedetto, M; Curl, W W

    1993-01-01

    This study was designed to determine the cause of upper trunk brachial plexopathy, which is referred to as a "stinger" or a "burner." This injury often has been thought to occur secondary to traction when an athlete sustains a lateral flexion injury of the neck. At the United States Military Academy, a 4-phase study was begun with 261 tackle football players (236 intramural- and 25 varsity-level players) to investigate this injury. Electromyography and nerve root stimulation studies were used to delineate the lesion, which was found in a total of 32 players who continued throughout the study. This study demonstrated that a much more common mechanism of injury resulting in the stinger syndrome is probably compression of the fixed brachial plexus between the shoulder pad and the superior medial scapula when the pad is pushed into the area of Erb's point, where the brachial plexus is most superficial. An orthosis was designed to protect the brachial plexus from the compressive force of the shoulder pad. In preliminary trials, this orthosis had been very effective in decreasing the number of episodes in which stinger injuries occurred. PMID:8238703

  7. Clinical Utility of (18)F-FDG PET/CT in brachial plexopathy secondary to metastatic breast cancer.

    PubMed

    Chandra, Piyush; Purandare, Nilendu; Agrawal, Archi; Shah, Sneha; Rangarajan, Venkatesh

    2016-01-01

    Role of fluorodeoxyglucose positron emission tomography/computed tomography (PET/CT) in breast cancer is rapidly evolving. Brachial plexopathy is a rare clinical entity in follow-up of operated breast cancer patients, who presents with disease recurrence in the axilla. Conventionally, magnetic resonance imaging is the imaging modality of choice for diagnostic evaluation in these cases and only few case reports/short studies have explored the utility of PET/CT in this clinical indication. We present here a short case series to demonstrate the utility of PET/CT as an important adjunctive imaging modality to magnetic resonance to supplement diagnosis of brachial plexopathy, differentiate radiation-induced brachial plexopathy from neoplastic plexopathy, accurately restage the disease and to monitor response to chemotherapy. PMID:27095861

  8. Clinical Utility of 18F-FDG PET/CT in brachial plexopathy secondary to metastatic breast cancer

    PubMed Central

    Chandra, Piyush; Purandare, Nilendu; Agrawal, Archi; Shah, Sneha; Rangarajan, Venkatesh

    2016-01-01

    Role of fluorodeoxyglucose positron emission tomography/computed tomography (PET/CT) in breast cancer is rapidly evolving. Brachial plexopathy is a rare clinical entity in follow-up of operated breast cancer patients, who presents with disease recurrence in the axilla. Conventionally, magnetic resonance imaging is the imaging modality of choice for diagnostic evaluation in these cases and only few case reports/short studies have explored the utility of PET/CT in this clinical indication. We present here a short case series to demonstrate the utility of PET/CT as an important adjunctive imaging modality to magnetic resonance to supplement diagnosis of brachial plexopathy, differentiate radiation-induced brachial plexopathy from neoplastic plexopathy, accurately restage the disease and to monitor response to chemotherapy.

  9. Shoulder pain and isolated brachial plexopathy.

    PubMed

    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

  10. Pediatric Stinger Syndrome: Acute Brachial Plexopathy After Minor Trauma.

    PubMed

    Quong, Whitney L; Hynes, Sally L; Arneja, Jugpal S

    2015-11-01

    The "stinger" or "burner" is a form of transient brachial plexopathy termed for its characteristic knife-like pain extending from the neck to the fingertips. Muscle weakness and paresthesia are oftentimes associated symptoms and are similarly temporary. Commonly observed in athletes of contact sports, the stinger results from high force trauma causing either traction/direct compression to the brachial plexus or extension/compression of the cervical nerve roots. We describe a pediatric case of a stinger in a 14-year-old boy, which was caused by a relatively low force trauma accident. Our management strategy and recommendations are discussed. PMID:26893985

  11. Pediatric Stinger Syndrome: Acute Brachial Plexopathy After Minor Trauma

    PubMed Central

    Quong, Whitney L.; Hynes, Sally L.

    2015-01-01

    Summary: The “stinger” or “burner” is a form of transient brachial plexopathy termed for its characteristic knife-like pain extending from the neck to the fingertips. Muscle weakness and paresthesia are oftentimes associated symptoms and are similarly temporary. Commonly observed in athletes of contact sports, the stinger results from high force trauma causing either traction/direct compression to the brachial plexus or extension/compression of the cervical nerve roots. We describe a pediatric case of a stinger in a 14-year-old boy, which was caused by a relatively low force trauma accident. Our management strategy and recommendations are discussed. PMID:26893985

  12. 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 patients.

  13. Permanent upper trunk plexopathy after interscalene brachial plexus block.

    PubMed

    Avellanet, Merce; Sala-Blanch, Xavier; Rodrigo, Lidia; Gonzalez-Viejo, Miguel A

    2016-02-01

    Interscalene brachial plexus block (IBPB) has been widely used in shoulder surgical procedures. The incidence of postoperative neural injury has been estimated to be as high as 3 %. We report a long-term neurologic deficit after a nerve stimulator assisted brachial plexus block. A 55 year-old male, with right shoulder impingement syndrome was scheduled for elective surgery. The patient was given an oral dose of 10 mg of diazepam prior to the nerve stimulator assisted brachial plexus block. The patient immediately complained, as soon as the needle was placed in the interscalene area, of a sharp pain in his right arm and he was sedated further. Twenty-four hours later, the patient complained of severe shoulder and arm pain that required an increased dose of analgesics. Severe peri-scapular atrophy developed over the following days. Electromyography studies revealed an upper trunk plexus injury with severe denervation of the supraspinatus, infraspinatus and deltoid muscles together with a moderate denervation of the biceps brachii muscle. Chest X-rays showed a diaphragmatic palsy which was not present post operatively. Pulmonary function tests were also affected. Phrenic nerve paralysis was still present 18 months after the block as was dysfunction of the brachial plexus resulting in an inability to perform flexion, abduction and external rotation of the right shoulder. Severe brachial plexopathy was probably due to a local anesthetic having been administrated through the perineurium and into the nerve fascicles. Severe brachial plexopathy is an uncommon but catastrophic complication of IBPB. We propose a clinical algorithm using ultrasound guidance during nerve blocks as a safer technique of regional anesthesia. PMID:25744163

  14. 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. PMID:25288846

  15. Electrodiagnostic localization of traumatic upper trunk brachial plexopathy.

    PubMed

    Di Benedetto, M; Markey, K

    1984-01-01

    Eighteen patients having traumatic upper trunk brachial plexopathy ("the stinger"), a common football injury, were investigated electrodiagnostically. Proximal nerve conduction was determined by stimulating the supraclavicular fossa and at the C5 root and recording from muscles supplied by the long thoracic, suprascapular, musculocutaneous, axillary, lateral pectoral and thoracodorsal nerves. The accessory nerve was stimulated in the lateral posterior triangle and the evoked potential recorded from the upper trapezius muscle. Median and ulnar nerves were also tested, sensory and motor fibers being stimulated peripherally and proximally. Conduction slowing was observed in 16 patients mainly in the proximal segments of the axillary, musculocutaneous, suprascapular and accessory nerves. The most commonly observed electromyographic abnormalities were an increase in polyphasic waves and decreased recruitment. Spontaneous activity was sparse. These abnormalities appear to result most likely from compression of the most superficially located fibers of the brachial plexus at Erb's point. As a significant etiologic factor, the impact of ill-fitting shoulder pads against the neck during a football tackle is suggested. This empirical observation was supported by the decrease of "stingers" after the improvement of the shoulder gear. PMID:6691790

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

    PubMed

    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

  17. 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

  18. Brachial Plexopathy/Nerve Root Avulsion in a Football Player: The Role of Electrodiagnostics

    PubMed Central

    Radecki, Jeffrey; Wolfe, Scott W.; Strauss, Helene L.; Mintz, Douglas N.

    2008-01-01

    Electromyography (EMG) studies are a useful tool in anatomical localization of peripheral nerve and brachial plexus injuries. They are especially helpful in distinguishing between brachial plexopathy and nerve root injuries where surgical intervention may be indicated. EMG can also assist in providing prognostic information after nerve injury as well as after nerve repair. In this case report, a football player presented with weakness in his right upper limb after a traction/traumatic injury to the right brachial plexus. EMG studies revealed evidence of both pre- and postganglionic injury to multiple cervical roots. The injury was substantial enough to cause nerve root avulsions involving the C6 and C7 levels. Surgical referral led to nerve grafts targeted at regaining function in shoulder abduction and elbow flexion. After surgery, the patient’s progress was monitored utilizing EMG to assist in identifying true axonal regeneration. PMID:18751870

  19. 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. PMID:25175852

  20. Herpetic Brachial Plexopathy: Application of Brachial Plexus Magnetic Resonance Imaging and Ultrasound-Guided Corticosteroid Injection.

    PubMed

    Kim, Jeong-Gil; Chung, Sun G

    2016-05-01

    Herpes zoster, commonly known as shingles, is an infectious viral disease characterized by painful, unilateral skin blisters occurring in specific sensory dermatomes. Motor paresis is reported in 0.5% to 5% of patients. Although the mechanism of zoster paresis is still unclear, the virus can spread from the dorsal root ganglia to the anterior horn cell or anterior spinal nerve roots. It rarely involves the brachial plexus. We report a case of brachial plexitis following herpes zoster infection in which pathological lesions were diagnosed using brachial plexus magnetic resonance imaging and treated with ultrasound-guided perineural corticosteroid injection. PMID:26829085

  1. 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. PMID:21988036

  2. 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

  3. Clinical, Electrophysiological Findings in Adult Patients with Non-traumatic Plexopathies

    PubMed Central

    Ko, Kiljun; Kang, Min Jae; Ko, Moon Ju; Do, Jong Gul; Sunwoo, Hyuk; Kwon, Tae Gun; Hwang, Jung Min; Park, Yoonhong

    2011-01-01

    Objective To ascertain the etiology of non-traumatic plexopathy and clarify the clinical, electrophysiological characteristics according to its etiology. Method We performed a retrospective analysis of 63 non-traumatic plexopathy patients that had been diagnosed by nerve conduction studies (NCS) and needle electromyography (EMG). Clinical, electrophysiological, imaging findings were obtained from medical records. Results We identified 36 cases with brachial plexopathy (BP) and 27 cases with lumbosacral plexopathy (LSP). The causes of plexopathy were neoplastic (36.1%), thoracic outlet syndrome (TOS) (25.0%), radiation induced (16.7%), neuralgic amyotrophy (8.3%), perioperative (5.6%), unknown (8.3%) in BP, while neoplastic (59.3%), radiation induced (22.2%), neuralgic amyotrophy (7.4%), psoas muscle abscess (3.7%), and unknown (7.4%) in LSP. In neoplastic plexopathy, pain presented as the first symptom in most patients (82.8%), with the lower trunk of the brachial plexus predominantly involved. In radiation induced plexopathy (RIP), pain was a common initial symptom, but the proportion was smaller (50%), and predominant involvements of bilateral lumbosacral plexus and whole trunk of brachial or lumbosacral plexus were characteristic. Myokymic discharges were noted in 41.7% patients with RIP. Abnormal NCS finding in the medial antebrachial cutaneous nerve was the most sensitive to diagnose TOS. Neuralgic amyotrophy of the brachial plexus showed upper trunk involvement in all cases. Conclusion By integrating anatomic, pathophysiologic knowledge with detailed clinical assessment and the results of ancillary studies, physicians can make an accurate diagnosis and prognosis. PMID:22506209

  4. 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. PMID:26991053

  5. Electrodiagnosis in common mononeuropathies and plexopathies.

    PubMed

    Jillapalli, Devanand; Shefner, Jeremy M

    2005-06-01

    Electrodiagnosis has a prominent role in the diagnosis of common entrapment neuropathies (carpal tunnel syndrome and ulnar neuropathy at the elbow) and plexopathies (idiopathic brachial plexopathy and diabetic lumbar radiculoplexopathy). The relevant anatomy and pathology of these disorders is reviewed in the context of electrodiagnosis and prognosis. PMID:15937735

  6. 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

  7. Migraine complicated by brachial plexopathy as displayed by MRI and MRA: aberrant subclavian artery and cervical ribs.

    PubMed Central

    Saxton, E. H.; Miller, T. Q.; Collins, J. D.

    1999-01-01

    This article describes migraine without aura since childhood in a patient with bilateral cervical ribs. In addition to usual migraine triggers, symptoms were triggered by neck extension and by arm abduction and external rotation; paresthesias and pain preceded migraine triggered by arm and neck movement. Suspected thoracic outlet syndrome was confirmed by high-resolution bilateral magnetic resonance imaging (MRI) and magnetic resonance angiography (MRA) of the brachial plexus. An unsuspected aberrant right subclavian artery was compressed within the scalene triangle. The aberrant subclavian artery splayed apart the recurrent laryngeal and vagus nerves, displaced the esophagus anteriorly, and effaced the right stellate ganglia and the C8-T1 nerve roots. Scarring and fibrosis of the left scalene triangle resulted in acute angulation of the neurovascular bundle and diminished blood flow in the subclavian artery and vein. A branch of the left sympathetic ganglia was displaced as it joined the C8-T1 nerve roots. Left scalenectomy and rib resection confirmed the MRI and MRA findings; the scalene triangle contents were decompressed, and migraine symptoms subsequently resolved. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 PMID:10388259

  8. Painful Lumbosacral Plexopathy

    PubMed Central

    Ehler, Edvard; Vyšata, Oldřich; Včelák, Radek; Pazdera, Ladislav

    2015-01-01

    Abstract Patients frequently suffer from lumbosacral plexus disorder. When conducting a neurological examination, it is essential to assess the extent of muscle paresis, sensory disorder distribution, pain occurrence, and blocked spine. An electromyography (EMG) can confirm axonal lesions and their severity and extent, root affliction (including dorsal branches), and disorders of motor and sensory fiber conduction. Imaging examination, particularly gadolinium magnetic resonance imaging (MRI) examination, ensues. Cerebrospinal fluid examination is of diagnostic importance with radiculopathy, neuroinfections, and for evidence of immunoglobulin synthesis. Differential diagnostics of lumbosacral plexopathy (LSP) include metabolic, oncological, inflammatory, ischemic, and autoimmune disorders. In the presented case study, a 64-year-old man developed an acute onset of painful LSP with a specific EMG finding, MRI showing evidence of plexus affliction but not in the proximal part of the roots. Painful plexopathy presented itself with severe muscle paresis in the femoral nerve and the obturator nerve innervation areas, and gradual remission occurred after 3 months. Autoimmune origin of painful LSP is presumed. We describe a rare case of patient with painful lumbar plexopathy, with EMG findings of axonal type, we suppose of autoimmune etiology. PMID:25929915

  9. 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.

  10. CT of the brachial plexus in patients with cancer

    SciTech Connect

    Cascino, T.L.; Kori, S.; Krol, G.; Foley, K.M.

    1983-12-01

    To assess the usefulness of CT, we reviewed 51 patients with clinically diagnosed brachial plexopathy who were seen between 1977 and 1981. The established etiology was metastatic tumor in 46 and radiation fibrosis in 5. CT was abnormal in 89% of tumor patients. Myelography, bone scan, and plain cervical spine radiographs were less useful. In four of five patients with radiation fibrosis, CT showed distortion of normal tissue planes without a discrete mass, but was not always distinguishable from tumor infiltration. CT of the brachial plexus provides the best two-dimensional view of tumor infiltration and detects bony changes earlier than standard radiographs. CT is a useful guide for surgical exploration of the brachial plexus, but does not differentiate tumor infiltration from radiation fibrosis.

  11. Brachial Plexus Injuries

    MedlinePlus

    ... Diversity Find People About NINDS NINDS Brachial Plexus Injuries Information Page Synonym(s): Erb's Palsy Table of Contents ( ... done? Clinical Trials Organizations What are Brachial Plexus Injuries? The brachial plexus is a network of nerves ...

  12. Iatrogenic postoperative brachial plexus compression secondary to hypertrophic non-union of a clavicle fracture

    PubMed Central

    Scadden, J

    2013-01-01

    The brachial plexus is related intimately to the clavicle such that injury can occur primarily and most commonly at the time of trauma through traction or it can occur secondarily, mainly owing to hypertrophic non-union with exuberant callus formation, causing compression of the plexus. The movement-dependent rearrangement of the subclavicular space is restricted with rigid internal fixation, thereby placing inappropriate pressure on the plexus from the deep hypertrophic tissue. This case highlights another cause of brachial plexopathy of which to be aware. PMID:23827280

  13. 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.

  14. Lumbar plexopathy after radical nephrectomy -A case report-

    PubMed Central

    Lee, Young-Bok; Jeong, Eui-Kyun

    2012-01-01

    Lumbar plexopathy is characterized by an abrupt onset of sensory disturbances, weakness, and loss of deep tendon reflexes of lower extremities. The various causes of lumbar plexopathy include trauma, infections, space-occupying lesion, vascular diseases, metabolic diseases, and the use of drugs such as heroin. Postoperative rhabdomyolysis occurs secondary to prolonged muscle compression due to surgical positioning. Herein, we report a case of lumbar plexopathy, complicating an injury to the paraspinal muscle and iliopsoas muscle that occurred in the flexed lateral decubitus position following radical nephrectomy. PMID:22379578

  15. 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, ...

  16. Radiotherapy-induced lumbosacral plexopathy in a patient with cervical cancer: a case report and literature review

    PubMed Central

    Kosobucki, Radosław; Łuczyńska, Elżbieta; Bieda, Tomasz; Urbański, Krzysztof

    2012-01-01

    Radiotherapy-induced lumbosacral plexopathy in cervical cancer treatment is a very rare, but extremely serious complication. The clinical course is associated with severe bilateral lower leg pain, reduced sensation, different degrees of weakness, paresis or paralysis, and sometimes also urinary or fecal incontinence. Patient quality of life becomes significantly deteriorated. Escalating neurological disorders may make self-sufficient functioning impossible. Neurological symptoms, most often irreversible, may develop at different times after irradiation, even after more than 30 years. We present a case of neurological toxicity in a patient successfully treated for cervical cancer with pelvis and para-aortic lymph node irradiation and weekly cisplatin. Neurological symptoms developed a few weeks after completion of external irradiation, were gradually escalating and resulted in complete immobilization of the woman. We underline the significance of long-term, systematic physiotherapy and pharmacological therapy which has resulted in significant improvement of motion efficiency. The literature review concerns the questions of frequency, clinical course and mechanisms of radiation-induced plexopathy. PMID:23788877

  17. Transient unilateral brachial plexopathy and partial Horner's syndrome following spinal anesthesia for cesarean section.

    PubMed

    Anson, Jonathan A; McQuillan, Patrick M

    2014-04-01

    A healthy 21-year-old primigravida presented for elective cesarean section. At 45 min after intrathecal (IT) injection of bupivacaine, morphine and fentanyl she developed dysphagia, right sided facial droop, ptosis and ulnar nerve weakness. This constellation of signs and symptoms resolved 2 h later. Based on the time course and laterality of her symptoms, as well as the pharmacologic properties of spinal opioids, we believe her symptoms can be attributed to the IT administration of fentanyl. PMID:24803773

  18. Brachial Plexus Block for Cancer-Related Pain: A Case Series.

    PubMed

    Zinboonyahgoon, Nantthasorn; Vlassakov, Kamen; Abrecht, Christ R; Srinivasan, Suresh; Narang, Sanjeet

    2015-01-01

    Neoplastic brachial plexopathy (NBP) is caused by a cancerous infiltration into the brachial plexus, presenting often as severe pain in the affected upper extremity. Such pain can be resistant to medical treatment. Invasive interventions such as brachial plexus neurolysis with phenol or cordotomy may result in severe complications including permanent neurological damage and death. Continuous brachial plexus and paravertebral block with local anesthetic have been reported to successfully control pain from NBP, but these techniques are logistically challenging and frequently have catheter-related complications. We report a series of patients who received single-shot brachial plexus blocks with a mixture of local anesthetic and corticosteroid (bupivacaine 0.25% with methyl-prednisolone 20-120 mg) for the treatment of refractory cancer-related pain in the brachial plexus territory, mostly from NBP. Theoretically, such blocks could provide immediate analgesia from the local anesthetic and a longer-lasting analgesia from the slow-release steroids. Responders reported a sustained decrease in their pain (lasting from 2 weeks to 10 months), a significant decrease in their opioid and non-opioid (ketamine, gabapentin) consumption, overall satisfaction with the block, and unchanged or improved function of their limb. The ideal candidate for this procedure is a patient who has pain that is predominantly neuropathic from a lesion within the brachial plexus and with anatomy amenable to ultrasound-guided nerve block. Our case series suggests that, in the appropriately selected patient, this technique can safely and effectively alleviate pain from NBP. The procedure is simple, spares limb function, and can be diagnostic, predicting response to more complex procedures. To the best of our knowledge, this is the first report using this technique for NBP. PMID:26431146

  19. Pediatric brachial plexus reconstruction.

    PubMed

    Terzis, Julia K; Kokkalis, Zinon T

    2009-12-01

    Obstetrical brachial plexus palsy is commonly attributed to excessive traction applied to the baby's neck during a difficult delivery. The majority of infants with brachial plexus palsy recover spontaneously within the first 3 months of life. However, in 10 to 30 percent of cases, the recovery is incomplete. Global palsy and the absence of biceps muscle function at 3 months of age have been adopted as the main indications for early brachial plexus microsurgery. In late cases or when primary reconstruction has not yielded satisfactory results, secondary reconstruction will intervene as an enhancement of a specific functional deficit or of the overall function of the upper extremity. In this article, the authors review the history of obstetrical brachial plexus palsy, the epidemiology and cause, and the indications for and the timing of surgery. The current diagnostic modalities and clinical evaluation of plexus injuries are also considered. The advances in electrophysiology, myelography, and computed tomographic scanning and magnetic resonance imaging are presented, all of which are important diagnostic modalities that facilitate a more accurate diagnosis. Obstetrical brachial plexus injuries may require multistaged reconstructive procedures, including neurolysis, resection of neuromas, identification of intraplexus and extraplexus donor nerves, selective neurotizations, selective nerve transfers, and nerve grafting. Finally, the various secondary procedures in terms of anatomical location in the upper extremity are described. Whatever the reports and results, the complex doctrine of obstetrical brachial plexus palsy continues to evolve with notable functional outcomes, but return to normal function remains a challenge for the future. PMID:19952705

  20. 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.

  1. [Radiation-induced cancers].

    PubMed

    Dutrillaux, B

    1998-01-01

    The induction of malignant diseases is one of the most concerning late effects of ionising radiation. A large amount of information has been collected form atomic bomb survivors, patients after therapeutic irradiation, occupational follow-up and accidentally exposed populations. Major uncertainties persist in the (very) low dose range i.e., population and workers radioprotection. A review of the biological mechanisms leading to cancer strongly suggests that the vast majority of radiation-induced malignancies arise as a consequence of recessive mutations of tumour-suppressor genes. These mutations can be unveiled by ageing, this process being possibly furthered by constitutional or acquired genomic instability. The individual risk is likely to be very low, probably because of the usual dose level. However, the magnitude of medical exposure and the reliance of our societies on nuclear industry are so high that irreproachable decision-making processes and standards for practice are inescapable. PMID:9868399

  2. 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.

  3. 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

  4. Idiopathic Brachial Neuritis

    PubMed Central

    Gonzalez-Alegre, Pedro; Recober, Ana; Kelkar, Praful

    2002-01-01

    Idiopathic brachial neuritis is a well defined clinical condition that most commonly affects young adults, seen usually by primary care physicians, neurologists or orthopaedic surgeons. Its onset is characterized by acute, aching shoulder pain lasting a few days to weeks, followed by progressive shoulder girdle and upper extremity weakness and atrophy, with a slow but progressive recovery of motor function over 6 to 18 months. Its early recognition can help avoid unnecessary and potentially harmful diagnostic and therapeutic interventions, and avoid delays in prescribing appropriate therapies that may be helpful only early in the course of the disease. We present a case of idiopathic brachial neuritis and discuss important aspects of the disease and difficulties in reaching the correct diagnosis. PMID:12180618

  5. Brachial artery pseudoaneurysm

    PubMed Central

    Kemp, Katie; Radwan, Rami; Shingler, Guy; Davies, Chris

    2014-01-01

    We describe a case of an elderly man who presented with an upper arm swelling that had developed following a humeral fracture 8 months previously. The swelling was painless but associated with significantly diminished motor function of his right hand and concurrent paraesthaesia. On examination, a large pulsatile mass was identified and CT angiography confirmed the presence of an 11×7 cm brachial artery pseudoaneurysm. The patient underwent surgical repair in which a fragment of the humerus was found to have punctured the brachial artery resulting in a pseudoaneurysm. The patient had an uncomplicated postoperative period and was discharged 2 days later having regained some motor function in his right hand. PMID:24859555

  6. Obstetric brachial plexus injury

    PubMed Central

    Thatte, Mukund R.; Mehta, Rujuta

    2011-01-01

    Obstetric brachial plexus injury (OBPI), also known as birth brachial plexus injury (BBPI), is unfortunately a rather common injury in newborn children. Incidence varies between 0.15 and 3 per 1000 live births in various series and countries. Although spontaneous recovery is known, there is a large subset which does not recover and needs primary or secondary surgical intervention. An extensive review of peer-reviewed publications has been done in this study, including clinical papers, review articles and systematic review of the subject. In addition, the authors experience of several hundred cases over the last 15 years has been added and has influenced the ultimate text. Causes of OBPI, indications of primary nerve surgery and secondary reconstruction of shoulder, etc. are discussed in detail. Although all affected children do not require surgery in infancy, a substantial proportion of them, however, require it and are better off for it. Secondary surgery is needed for shoulder elbow and hand problems. Results of nerve surgery are very encouraging. Children with OBPI should be seen early by a hand surgeon dealing with brachial plexus injuries. Good results are possible with early and appropriate intervention even in severe cases. PMID:22279269

  7. 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 themselves to prolonged study, many tend to eliminate or rearrange the target chromosome until it is too small for further rearrangement. The observed frequency of induced instability by low and high linear-energy-transfer radiations greatly exceeds that observed for nuclear gene mutations at similar doses; hence, mutation of a gene or gene family is unlikely to be the initiating mechanism. Once initiated however, there is evidence in the GM10115 model system that it can be perpetuated over time by dicentric chromosome formation followed by bridge breakage fusion cycles (Marder and Morgan 1993), as well as recombinational events involving interstitial telomere like repeat sequences (Day et al. 1998). There is also increasing evidence that inflammatory type reactions (Lorimore et al. 2001, Lorimore and Wright 2003), presumably involving reactive oxygen and nitrogen species as well as cytokines and chemokines might be involved in driving the ustable phenotype (Liaikis et al. 2007, Hei et al. 2008). To this end there is very convincing evidence for such reactions being involved in another non-targeted effect associated with ionizing radiation, the bystander effect (Hei et al. 2008). Clearly the link between induced instability and bystander effects suggests common processes and inflammatory type reactions will likely be the subject of future investigation.

  8. Axillary Brachial Plexus Block

    PubMed Central

    Satapathy, Ashish R.; Coventry, David M.

    2011-01-01

    The axillary approach to brachial plexus blockade provides satisfactory anaesthesia for elbow, forearm, and hand surgery and also provides reliable cutaneous anaesthesia of the inner upper arm including the medial cutaneous nerve of arm and intercostobrachial nerve, areas often missed with other approaches. In addition, the axillary approach remains the safest of the four main options, as it does not risk blockade of the phrenic nerve, nor does it have the potential to cause pneumothorax, making it an ideal option for day case surgery. Historically, single-injection techniques have not provided reliable blockade in the musculocutaneous and radial nerve territories, but success rates have greatly improved with multiple-injection techniques whether using nerve stimulation or ultrasound guidance. Complete, reliable, rapid, and safe blockade of the arm is now achievable, and the paper summarizes the current position with particular reference to ultrasound guidance. PMID:21716725

  9. Congenital brachial plexus exploration.

    PubMed

    Hentz, Vincent R

    2004-06-01

    Stanford's experience in the management of obstetrical brachial plexus palsy dates from 1983. A formal clinic service began in 1992. The tenets of management include early evaluations, a dependency on sequential evolution for decision-making, and very early neural surgery for babies with abnormal hands. We watch babies with normal hands for a longer time before advising surgery. At exploration, common patterns of injury are observed. Intraoperative evoked potentials are used to make surgical decisions. Reconstructive goals for upper plexus injuries include shoulder and elbow control. The paramount goal for babies with global palsies is hand function. Therapy throughout the child's growth years is vital. Sequelae, particularly shoulder contractures, require early surgical intervention. Secondary reconstructive procedures are typically beneficial in improving function. Since 1992, over 400 children have been examined, 62 have had neural reconstruction, and 102 have undergone secondary procedures. Surgery has been remarkably complication free. All children having neural reconstruction except 2 have been benefited. PMID:16518116

  10. Brachial plexus injury in newborns

    MedlinePlus

    ... and vascular disorders. In: Fenichel GM, ed. Neonatal Neurology . 4th ed. Philadelphia, PA: Elsevier Churchill Livingstone; 2006: ... CB, Kratz JR, Jelin AC, Gelfand AA. Child neurology: brachial plexus birth injury: what every neurologist needs ...

  11. 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

  12. Evaluation of Neoplastic Involvement of Brachial and Lumbosacral PlexusImaging Aspects.

    PubMed

    Krol, G

    1993-01-01

    Traditionally, the regions of brachial and lumbosacral plexi have been difficult to evaluate, both by physical examination and conventional radiography. Presenting symptoms of plexus involvement may include pain, paresthesia, focal weakness, sensory deficits, and muscle atrophy. The symptomatology as well as electrodiagnostic studies are nonspecific and many conditions, such as mechanical compromise of the pathway by a benign process, inflammation, and infiltration by a neoplasm originating or metastatic to the region of plexi share similar features and cannot be differentiated. A general term "brachial or lumbosacral plexopathy" is universally used, to describe a variety of clinical syndromes, including tumor infiltration, neuritis, postsurgical, and postradiation changes as well as idiopathic conditions. Significant progress in detection and assessment of the extent of plexus disease has been made after introduction of computed tomography (CT). Further anatomical detail and tissue characteristics have been provided by magnetic resonance imaging (MRI). However, in spite of valuable contribution from both imaging methods, the plexi frequently present a challenging problem for a clinician as well as for a radiologist. PMID:24573024

  13. Internal iliac artery pseudoaneurysm: an unusual cause of sciatica and lumbosacral plexopathy.

    PubMed

    Melikoglu, Meltem Alkan; Kocabas, Hilal; Sezer, Ilhan; Akdag, Ali; Gilgil, Erdal; Butun, Bulent

    2008-08-01

    This report describes an unusual case of lumbosacral plexopathy resulting from internal iliac artery pseudoaneurysm. A 50-yr-old woman presented with multiple penetrating trauma to the thorax, abdomen, and left buttock. Several weeks after the injury, severe sciatica and motor dysfunction developed in her left leg. Progressively worsening pain was followed by left foot drop. An electrodiagnostic evaluation suggested a lower lumbosacral plexopathy. Magnetic resonance imaging showed a hematoma extending adjacent to the left lumbosacral plexus. Computerized tomographic angiography revealed a left internal iliac artery pseudoaneurysm. The pseudoaneurysm was excised surgically. In the early postoperative period, the patient reported total relief of pain. Her motor function recovered gradually over several weeks; however, some residual weakness of foot dorsiflexion persisted. With this case presentation, we underscore that an arterial pseudoaneurysm should be remembered as an etiologic possibility of lumbosacral plexopathy and sciatica, especially in patients with history of iatrogenic or accidental trauma. An increased awareness of this rare cause of sciatica and lumbosacral plexopathy may enable early intervention alternatives. PMID:18388559

  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. 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.

  16. Lumbosacral Plexopathy Caused by Presacral Recurrence of Colon Cancer Mimicking Degenerative Spinal Disease: A Case Report

    PubMed Central

    Jo, Se Yeong; Jeong, Je Hoon; Cha, Jang Gyu

    2015-01-01

    Radiculopathy triggered by degenerative spinal disease is the most common cause of spinal surgery, and the number of affected elderly patients is increasing. Radiating pain that is extraspinal in origin may distract from the surgical decision on how to treat a neurological presentation in the lower extremities. A 54-year-old man with sciatica visited our outpatient clinic. He had undergone laminectomy and discectomy to treat spinal stenosis at another hospital, but his pain remained. Finally, he was diagnosed with a plexopathy caused by late recurrence of colorectal cancer, which compressed the lumbar plexus in the presacral area. This case report illustrates the potential for misdiagnosis of extraspinal plexopathy and the value of obtaining an accurate history. Although the symptoms are similar, spinal surgeons should consider both spinal and extraspinal origins of sciatica. PMID:26217393

  17. Radiation-induced parotid cancer

    SciTech Connect

    Walker, M.J.; Chaudhuri, P.K.; Wood, D.C.; Das Gupta, T.K.

    1981-03-01

    A retrospective analysis of 72 cases of primary malignant tumors of the parotid gland treated at the University of Illinois Hospital, Chicago, from 1950 through 1978 revealed that six of these had developed from two to 24 years after irradiation of the head or neck for various benign and malignant neoplastic conditions. At the time of irradiation, ages ranged from 7 to 73 years; the sex distribution was equal. From our findings and those in 26 cases reported by various other authors, the following criteria are proposed for the designation of a parotid tumor as being radiation induced: (1) well-documented radiation exposure; (2) part of irradiation must incorporate the gland in which the cancer subseqently arises; (3) exposure to a minimum of 300 rads; and (4) minimum latent period of two years. In view of the widespread use in the past of heat and neck irradiation of benign neoplastic disease, the surgeon should be aware of this possible link with parotid gland tumor.

  18. Brachial neuritis following a corticosteroid injection

    PubMed Central

    Robinson, Matthew; Fulcher, Mark

    2014-01-01

    This report presents a case of brachial neuritis following a subacromial corticosteroid injection. The patient developed an anterior interosseous neuropathy shortly after the injection, with no other trigger being identified. This neuropathy has unfortunately not shown any sign of recovery at 2 years. The authors propose that corticosteroid injection be added to the list of possible triggering events of brachial neuritis and highlight the frequent use of oral corticosteroids in its treatment. (1) The injection of local anaesthetic and corticosteroid should be considered as a potential trigger for brachial neuritis. (2) Brachial neuritis should be considered in the differential diagnosis for patients presenting with severe arm pain and weakness. (3) The nerves originating from the upper trunk of the brachial plexus are most commonly affected. (4) The anterior interosseous nerve is involved in one-third of cases. PMID:24596414

  19. 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.

  20. 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.

  1. Lumbar plexopathy as a complication of percutaneous nephrolithotomy in a horseshoe kidney

    PubMed Central

    Lantz, Andrea G.; Honey, R. John D’A

    2015-01-01

    Treatment of nephrolithiasis in horseshoe kidneys can be challenging due to anomalies in renal position, collecting system anatomy and vascular supply. We report on a patient who was referred after a failed percutaneous nephrolithotomy for a left moiety staghorn calculus in a horseshoe kidney. Two punctures had been performed involving upper and middle posterior calyces. Both were very medially placed and inadvertently traversed the psoas muscle, resulting in lumbar plexopathy with permanent deficit. This complication presented postoperatively with left leg weakness, paresthesia, and pain which impaired independent ambulation. The patient went on to be successfully treated for her stone disease with robotic-assisted laparoscopic pyelolithotomy. PMID:25737767

  2. Lumbar plexopathy as a complication of percutaneous nephrolithotomy in a horseshoe kidney.

    PubMed

    Lantz, Andrea G; Honey, R John D'A

    2015-01-01

    Treatment of nephrolithiasis in horseshoe kidneys can be challenging due to anomalies in renal position, collecting system anatomy and vascular supply. We report on a patient who was referred after a failed percutaneous nephrolithotomy for a left moiety staghorn calculus in a horseshoe kidney. Two punctures had been performed involving upper and middle posterior calyces. Both were very medially placed and inadvertently traversed the psoas muscle, resulting in lumbar plexopathy with permanent deficit. This complication presented postoperatively with left leg weakness, paresthesia, and pain which impaired independent ambulation. The patient went on to be successfully treated for her stone disease with robotic-assisted laparoscopic pyelolithotomy. PMID:25737767

  3. 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. PMID:10710825

  4. 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.

  5. Radiation-induced leukemias in ankylosing spondylitis

    SciTech Connect

    Toolis, F.; Potter, B.; Allan, N.C.; Langlands, A.O.

    1981-10-01

    Three cases of leukemia occurred in patients with ankylosing spondylitis treated by radiotherapy. In each case, the leukemic process exhibited bizarre features suggesting that radiation is likely to induce atypical forms of leukemia possessing unusual attributes not shared by spontaneously developing leukemia. The likely distinctive aspects of radiation-induced leukemia are discussed.

  6. 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

  7. 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.

  8. Bile acids in radiation-induced diarrhea

    SciTech Connect

    Arlow, F.L.; Dekovich, A.A.; Priest, R.J.; Beher, W.T.

    1987-10-01

    Radiation-induced bowel disease manifested by debilitating diarrhea is an unfortunate consequence of therapeutic irradiation for pelvic malignancies. Although the mechanism for this diarrhea is not well understood, many believe it is the result of damage to small bowel mucosa and subsequent bile acid malabsorption. Excess amounts of bile acids, especially the dihydroxy components, are known to induce water and electrolyte secretion and increase bowel motility. We have directly measured individual and total bile acids in the stool samples of 11 patients with radiation-induced diarrhea and have found bile acids elevated two to six times normal in eight of them. Our patients with diarrhea and increased bile acids in their stools had prompt improvement when given cholestyramine. They had fewer stools and returned to a more normal life-style.

  9. Management of radiation-induced urethral strictures

    PubMed Central

    Hofer, Matthias D.

    2015-01-01

    Radiation as a treatment option for prostate cancer has been chosen by many patients. One of the side effects encountered are radiation-induced urethral strictures which occur in up to 11% of patients. Radiation damage has often left the irradiated field fibrotic and with poor vascularization which make these strictures a challenging entity to treat. The mainstay of urologic management remains an urethroplasty procedure for which several approaches exist with variable optimal indication. Excision and primary anastomoses are ideal for shorter bulbar strictures that comprise the majority of radiation-induced urethral strictures. One advantage of this technique is that it does not require tissue transfers and success rates of 70-95% have consistently been reported. Substitution urethroplasty using remote graft tissue such as buccal mucosa are indicated if the length of the stricture precludes a tension-free primary anastomosis. Despite the challenge of graft survival in radiation-damaged and poorly vascularized recipient tissue, up to 83% of patients have been treated successfully although the numbers described in the literature are small. The most extensive repairs involve the use of tissue flaps, for example gracilis muscle, which may be required if the involved periurethral tissue is unable to provide sufficient vascular support for a post-operative urethral healing process. In summary, radiation-induced urethral strictures are a challenging entity. Most strictures are amenable to excision and primary anastomosis (EPA) with encouraging success rates but substitution urethroplasty may be indicated when extensive repair is needed. PMID:26816812

  10. Imaging Radiation-Induced Normal Tissue Injury

    PubMed Central

    Robbins, Mike E.; Brunso-Bechtold, Judy K.; Peiffer, Ann M.; Tsien, Christina I.; Bailey, Janet E.; Marks, Lawrence B.

    2013-01-01

    Technological developments in radiation therapy and other cancer therapies have led to a progressive increase in five-year survival rates over the last few decades. Although acute effects have been largely minimized by both technical advances and medical interventions, late effects remain a concern. Indeed, the need to identify those individuals who will develop radiation-induced late effects, and to develop interventions to prevent or ameliorate these late effects is a critical area of radiobiology research. In the last two decades, preclinical studies have clearly established that late radiation injury can be prevented/ameliorated by pharmacological therapies aimed at modulating the cascade of events leading to the clinical expression of radiation-induced late effects. These insights have been accompanied by significant technological advances in imaging that are moving radiation oncology and normal tissue radiobiology from disciplines driven by anatomy and macrostructure to ones in which important quantitative functional, microstructural, and metabolic data can be noninvasively and serially determined. In the current article, we review use of positron emission tomography (PET), single photon emission tomography (SPECT), magnetic resonance (MR) imaging and MR spectroscopy to generate pathophysiological and functional data in the central nervous system, lung, and heart that offer the promise of, (1) identifying individuals who are at risk of developing radiation-induced late effects, and (2) monitoring the efficacy of interventions to prevent/ameliorate them. PMID:22348250

  11. Quercetin Inhibits Radiation-Induced Skin Fibrosis

    PubMed Central

    Horton, Jason A.; Li, Fei; Chung, Eun Joo; Hudak, Kathryn; White, Ayla; Krausz, Kristopher; Gonzalez, Frank; Citrin, Deborah

    2013-01-01

    Radiation induced fibrosis of the skin is a late toxicity that may result in loss of function due to reduced range of motion and pain. The current study sought to determine if oral delivery of quercetin mitigates radiation-induced cutaneous injury. Female C3H/HeN mice were fed control chow or quercetin-formulated chow (1% by weight). The right hind leg was exposed to 35 Gy of X rays and the mice were followed serially to assess acute toxicity and hind leg extension. Tissue samples were collected for assessment of soluble collagen and tissue cytokines. Human and murine fibroblasts were subjected to clonogenic assays to determine the effects of quercetin on radiation response. Contractility of fibroblasts was assessed with a collagen contraction assay in the presence or absence of quercetin and transforming growth factor-β (TGF-β). Western blotting of proteins involved in fibroblast contractility and TGF-β signaling were performed. Quercetin treatment significantly reduced hind limb contracture, collagen accumulation and expression of TGF-β in irradiated skin. Quercetin had no effect on the radioresponse of fibroblasts or murine tumors, but was capable of reducing the contractility of fibroblasts in response to TGF-β, an effect that correlated with partial stabilization of phosphorylated cofilin. Quercetin is capable of mitigating radiation induced skin fibrosis and should be further explored as a therapy for radiation fibrosis. PMID:23819596

  12. [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. PMID:12494809

  13. Radiation-induced long thoracic nerve palsy

    SciTech Connect

    Pugliese, G.N.; Green, R.F.; Antonacci, A.

    1987-09-15

    The incidence of long thoracic nerve palsy after radical mastectomy has been documented to be approximately 10%. No cases have been reported after the more recent treatment for breast cancer, lumpectomy with axillary dissection. This more recent surgical procedure is customarily followed by aggressive radiation therapy to the remaining breast tissue. This is the first case report of a patient with radiation-induced long thoracic nerve palsy. The patient was a young woman who underwent left breast quadrantectomy and axillary dissection for breast cancer. After radiation therapy, she had isolated left long thoracic nerve palsy. The diagnosis was confirmed by electrodiagnostic studies. Almost full recovery occurred after 5 months.

  14. Radiation-induced hydrogen transfer in metals

    NASA Astrophysics Data System (ADS)

    Tyurin, Yu I.; Vlasov, V. A.; Dolgov, A. S.

    2015-11-01

    The paper presents processes of hydrogen (deuterium) diffusion and release from hydrogen-saturated condensed matters in atomic, molecular and ionized states under the influence of the electron beam and X-ray radiation in the pre-threshold region. The dependence is described between the hydrogen isotope release intensity and the current density and the electron beam energy affecting sample, hydrogen concentration in the material volume and time of radiation exposure to the sample. The energy distribution of the emitted positive ions of hydrogen isotopes is investigated herein. Mechanisms of radiation-induced hydrogen transfer in condensed matters are suggested.

  15. 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.

  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. Treatment options for brachial plexus injuries.

    PubMed

    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

  18. 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

  19. Triptolide Mitigates Radiation-Induced Pulmonary Fibrosis.

    PubMed

    Yang, Shanmin; Zhang, Mei; Chen, Chun; Cao, Yongbin; Tian, Yeping; Guo, Yangsong; Zhang, Bingrong; Wang, Xiaohui; Yin, Liangjie; Zhang, Zhenhuan; O'Dell, Walter; Okunieff, Paul; Zhang, Lurong

    2015-11-01

    Triptolide (TPL) may mitigate radiation-induced late pulmonary side effects through its inhibition of global pro-inflammatory cytokines. In this study, we evaluated the effect of TPL in C57BL/6 mice, the animals were exposed to radiation with vehicle (15 Gy), radiation with TPL (0.25 mg/kg i.v., twice weekly for 1, 2 and 3 months), radiation and celecoxib (CLX) (30 mg/kg) and sham irradiation. Cultured supernatant of irradiated RAW 264.7 and MLE-15 cells and lung lysate in different groups were enzyme-linked immunosorbent assays at 33 h. Respiratory rate, pulmonary compliance and pulmonary density were measured at 5 months in all groups. The groups exposed to radiation with vehicle and radiation with TPL exhibited significant differences in respiratory rate and pulmonary compliance (480 ± 75/min vs. 378 ± 76/min; 0.6 ± 0.1 ml/cm H2O/p kg vs. 0.9 ± 0.2 ml/cm H2O/p kg). Seventeen cytokines were significantly reduced in the lung lysate of the radiation exposure with TPL group at 5 months compared to that of the radiation with vehicle group, including profibrotic cytokines implicated in pulmonary fibrosis, such as IL-1β, TGF- β1 and IL-13. The radiation exposure with TPL mice exhibited a 41% reduction of pulmonary density and a 25% reduction of hydroxyproline in the lung, compared to that of radiation with vehicle mice. The trichrome-stained area of fibrotic foci and pathological scaling in sections of the mice treated with radiation and TPL mice were significantly less than those of the radiation with vehicle-treated group. In addition, the radiation with TPL-treated mice exhibited a trend of improved survival rate compared to that of the radiation with vehicle-treated mice at 5 months (83% vs. 53%). Three radiation-induced profibrotic cytokines in the radiation with vehicle-treated group were significantly reduced by TPL treatment, and this partly contributed to the trend of improved survival rate and pulmonary density and function and the decreased severity of pulmonary fibrosis at 5 months. Our findings indicate that TPL could be a potential new agent to mitigate radiation-induced pulmonary fibrosis. PMID:26488756

  20. 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.

  1. Radiation-induced electron migration along DNA

    SciTech Connect

    Fuciarelli, A.F.; Sisk, E.C.; Miller, J.H.; Zimbrick, J.D.

    1994-04-01

    Radiation-induced electron migration along DNA is a mechanism by which randomly produced stochastic energy deposition events can lead to nonrandom types of damage along DNA manifested distal to the sites of the initial energy deposition. Electron migration along DNA is significantly influenced by the DNA base sequence and DNA conformation. Migration along 7 base pairs in oligonucleotides containing guanine bases was observed for oligonucleotides irradiated in solution which compares to average migration distances of 6 to 10 bases for Escherichia coli DNA irradiated in solution and 5.5 base pairs for Escherichia coli DNA irradiated in cells. Evidence also suggests that electron migration can occur preferentially in the 5{prime} to 3{prime} direction along DNA. Our continued efforts will provide information regarding the contribution of electron transfer along DNA to formation of locally multiply damaged sites created in DNA by exposure to ionizing radiation.

  2. 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. PMID:25568739

  3. Management of radiation-induced rectal bleeding.

    PubMed

    Laterza, Liboria; Cecinato, Paolo; Guido, Alessandra; Mussetto, Alessandro; Fuccio, Lorenzo

    2013-11-01

    Pelvic radiation disease is one of the major complication after radiotherapy for pelvic cancers. The most commonly reported symptom is rectal bleeding which affects patients' quality of life. Therapeutic strategies for rectal bleeding are generally ignored and include medical, endoscopic, and hyperbaric oxygen treatments. Most cases of radiation-induced bleeding are mild and self-limiting, and treatment is normally not indicated. In cases of clinically significant bleeding (i.e. anaemia), medical therapies, including stool softeners, sucralfate enemas, and metronidazole, should be considered as first-line treatment options. In cases of failure, endoscopic therapy, mainly represented by argon plasma coagulation and hyperbaric oxygen treatments, are valid and complementary second-line treatment strategies. Although current treatment options are not always supported by high-quality studies, patients should be reassured that treatment options exist and success is achieved in most cases if the patient is referred to a dedicated centre. PMID:24101202

  4. Radiation-induced autophagy: mechanisms and consequences.

    PubMed

    Chaurasia, Madhuri; Bhatt, Anant Narayan; Das, Asmita; Dwarakanath, Bilikere S; Sharma, Kulbhushan

    2016-03-01

    Autophagy is an evolutionary conserved, indispensable, lysosome-mediated degradation process, which helps in maintaining homeostasis during various cellular traumas. During stress, a context-dependent role of autophagy has been observed which drives the cell towards survival or death depending upon the type, time, and extent of the damage. The process of autophagy is stimulated during various cellular insults, e.g. oxidative stress, endoplasmic reticulum stress, imbalances in calcium homeostasis, and altered mitochondrial potential. Ionizing radiation causes ROS-dependent as well as ROS-independent damage in cells that involve macromolecular (mainly DNA) damage, as well as ER stress induction, both capable of inducing autophagy. This review summarizes the current understanding on the roles of oxidative stress, ER stress, DNA damage, altered mitochondrial potential, and calcium imbalance in radiation-induced autophagy as well as the merits and limitations of targeting autophagy as an approach for radioprotection and radiosensitization. PMID:26764568

  5. 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.

  6. 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.

  7. Radiation-induced coronary artery disease.

    PubMed

    Mert, M; Arat-Ozkan, A; Ozkara, A; Aydemir, N A; Babalik, E

    2003-08-01

    Radiation-induced heart disease must be considered in any patient with cardiac symptomatology who had prior mediastinal irradiation. Radiation can affect all the structures in the heart, including the pericardium, the myocardium, the valves and the conduction system. In addition to these pathologies, coronary artery disease following mediastinal radiotherapy is the most actual cardiac pathology as it may cause cardiac emergencies requiring interventional cardiological or surgical interventions. Case A 36-year-old man was admitted to the clinic with unstable angina pectoris of one month duration. The patient had no coronary artery disease risk factor. The history of the patient revealed that he had mediastinal radiotherapy due to Hodgkin's disease at 10-year of age. Coronary arteriography showed total occlusion of the left anterior descending artery and 70% stenosis of the proximal right coronary artery. Both arteries are dilated with placement of two stents. Control coronary arteriography at the end of the first year showed patency of both stents and the patient is free of symptoms. Previous radiotherapy to the mediastinum should be considered as a risk factor for the development of premature coronary artery disease. Percutaneous transluminal coronary angioplasty with stent placement or surgical revascularization are the preferred methods of treatment. Preoperative assessment of internal thoracic arteries should be considered prior to surgery. As the radiation therapy is currently the standard treatment for a number of mediastinal malignancies, routine screening of these patients and optimal cardiac prevention during radiotherapy are the only ways to minimize the incidence of radiation-induced heart disease. PMID:14579846

  8. Central Adaptation following Brachial Plexus Injury.

    PubMed

    Simon, Neil G; Franz, Colin K; Gupta, Nalin; Alden, Tord; Kliot, Michel

    2016-01-01

    Brachial plexus trauma (BPT) often affects young patients and may result in lasting functional deficits. Standard care following BPT involves monitoring for clinical and electrophysiological evidence of muscle reinnervation, with surgical treatment decisions based on the presence or absence of spontaneous recovery. Data are emerging to suggest that central and peripheral adaptation may play a role in recovery following BPT. The present review highlights adaptive and maladaptive mechanisms of central and peripheral nervous system changes following BPT that may contribute to functional outcomes. Rehabilitation and other treatment strategies that harness or modulate these intrinsic adaptive mechanisms may improve functional outcomes following BPT. PMID:26409073

  9. Partial brachial plexus paresis in three calves.

    PubMed

    Rüegsegger, F; Steffen, F; Nuss, K A

    2012-10-20

    Partial brachial plexus paresis was diagnosed in three calves with unilateral functional lameness in a forelimb based on clinical and neurologic examinations. Clinical signs of radial nerve paresis were the main presenting problems. Electromyography was used to identify the affected nerves with the calves under general anaesthesia. Abnormal spontaneous activity of denervated muscles showed that the radial, musculocutaneous, median and ulnar nerves were compromised. The calves were treated medically, using splint bandages, and with physiotherapy. All calves regained function of the affected legs and normal weight bearing. PMID:22952132

  10. Fluorodeoxyglucose and 11C-Choline positron emission tomography for distinction of metastatic plexopathy and neuritis: a case report

    PubMed Central

    2009-01-01

    Introduction Fluorodeoxyglucose positron emission tomography scanning has an established role in the diagnostic work-up of many malignant diseases and also in the evaluation of cancer treatment response. Fluorodeoxyglucose positron emission tomography may, however be non-specific as infectious processes are depicted as well. Case presentation We present a patient with longstanding leg pain and weakness due to plexopathy developed a few years after treatment for prostate cancer. Prostate-specific antigen was raised and magnetic resonance imaging showed contrast uptake in thickened sacral nerves, suspicious for metastasis. While fluorodeoxyglucose positron emission tomography showed increased uptake in the plexus region, 11C-Choline- positron emission tomography did not show any uptake. It was concluded that the FDG uptake reflected plexus neuritis and no tumor. Treatment for pain relief was started. Conclusion 11C-Choline- positron emission tomography can be used to detect metastasis in patients with plexopathy suspicious for malignancy, while fluorodeoxyglucose positron emission tomography is more sensitive to inflammatory processes. PMID:20066056

  11. Arachnoid cyst masquerading as obstetric brachial plexus palsy.

    PubMed

    Muthukumar, Natarajan; Santhanakrishnan, Alwar Govindan; Sivakumar, Krishnaswamy

    2012-07-01

    Obstetric brachial plexus palsy is not uncommon. However, lesions masquerading as obstetric brachial plexus palsy are rare. A child with a cervicothoracic arachnoid cyst masquerading as obstetric brachial plexus palsy is presented, and the relevant literature is reviewed. A girl born by vaginal delivery at full term without any antecedent risk factors for obstetric brachial plexus palsy was noted to have decreased movements of the right upper extremity. After 7 months, there was no improvement. An MRI scan was obtained, which revealed a cervicothoracic spinal extradural arachnoid cyst. During surgery, the cyst was found to communicate with the dura at the axilla of the C-7 nerve root. The cyst was excised in toto. Six months later, there was improvement in the infant's neurological status. This case illustrates that spinal arachnoid cysts should be entertained in the differential diagnosis when a child presents with obstetric brachial plexus palsy without known antecedent risk factors for obstetric palsy. PMID:22681321

  12. Radiation-induced cancer: a modern view

    PubMed Central

    Shah, D J; Sachs, R K; Wilson, D J

    2012-01-01

    Diagnostic medical radiation has been the most rapidly increasing component of population background radiation exposure in Western countries over the past decade. This trend is set to increase as CT scanning is readily available with burgeoning use in everyday clinical practice. Consequently, the issue of cancer induction from the doses received during diagnostic medical exposures is highly relevant. In this review we explain current understanding of potential cancer induction at low doses of sparsely ionising radiation. For cancers that may be induced at low doses, a mechanistic description of radiation-induced cancer is discussed, which, in combination with extrapolation of data based on population cohort studies, provides the basis of the currently accepted linear no-threshold model. We explore the assumptions made in deriving risk estimates, the controversies surrounding the linear no-threshold model and the potential future challenges facing clinicians and policy-makers with regards to diagnostic medical radiation and cancer risk, most notably the uncertainties regarding deriving risk estimates from epidemiological data at low doses. PMID:23175483

  13. Estrogen Protects against Radiation-Induced Cataractogenesis

    PubMed Central

    Dynlacht, Joseph R.; Valluri, Shailaja; Lopez, Jennifer; Greer, Falon; DesRosiers, Colleen; Caperell-Grant, Andrea; Mendonca, Marc S.; Bigsby, Robert M.

    2008-01-01

    Cataractogenesis is a complication of radiotherapy when the eye is included in the treatment field. Low doses of densely ionizing space radiation may also result in an increased risk of cataracts in astronauts. We previously reported that estrogen (17-β-estradiol), when administered to ovariectomized rats commencing 1 week before γ irradiation of the eye and continuously thereafter, results in a significant increase in the rate and incidence of cataract formation and a decreased latent period compared to an ovariectomized control group. We therefore concluded that estrogen accelerates progression of radiation-induced opacification. We now show that estrogen, if administered continuously, but commencing after irradiation, protects against radiation cataractogenesis. Both the rate of progression and incidence of cataracts were greatly reduced in ovariectomized rats that received estrogen treatment after irradiation compared to ovariectomized rats. As in our previous study, estradiol administered 1 week prior to irradiation at the time of ovariectomy and throughout the period of observation produced an enhanced rate of cataract progression. Estrogen administered for only 1 week prior to irradiation had no effect on the rate of progression but resulted in a slight reduction in the incidence. We conclude that estrogen may enhance or protect against radiation cataractogenesis, depending on when it is administered relative to the time of irradiation, and may differentially modulate the initiation and progression phases of cataractogenesis. These data have important implications for astronauts and radiotherapy patients. PMID:19138041

  14. Management of brachial artery aneurisms in infants.

    PubMed

    Pagès, Olivier N; Alicchio, Francesca; Keren, Boris; Diallo, Saidou; Lefebvre, Francis; Valla, Jean S; Poli-Merol, Marie L

    2008-04-01

    Brachial artery aneurisms in children under 1 year of age are very rare. The main risk is distal ischaemic complication. We report four infants suffering from brachial artery aneurism of unknown origin. In all cases we used Doppler ultrasonography to validate the clinical diagnosis. Pre-operative vascular check-up was negative for other aneurismal location. Surgical excision with direct end-to-end anastomosis was possible in one patient; the others required interposition of an autologous venous graft. At discharge, patients were given oral aspirin for a few weeks. Histological examination revealed one pseudoaneurism and three true aneurisms. There were no complications either postoperatively or at 18 months follow-up. Arterial ligation might be indicated in only two situations: aneurism distal to profunda brachii artery, or chronic wall thrombus completely occluding (but distal perfusion through a neovascularization must be assessed first on angiography). Surgical excision with arterial reconstruction is the standard treatment. Endovascular treatment is not suitable because such a procedure in an infant would generate excessive radiation exposure, and a risk of stent migration with limb growth. In the case of an initial isolated and idiopathic presentation, or of false aneurism, clinical follow-up at 1 year is sufficient. In the case of secondary lesion, multiple initial presentation or relapse, life-long follow-up with repeated corporal imaging should be performed. PMID:18330576

  15. Hemodynamic significance of high brachial pulse pressure in young men.

    PubMed

    Alfie, José; Majul, Claudio; Paez, Olga; Galarza, Carlos; Waisman, Gabriel

    2004-04-01

    This study investigates whether an increased brachial pulse pressure (PP) in young healthy men constitutes a representative measure of the central hemodynamic forces, or the mere expression of an exaggerated upper limb amplification. Thirty two healthy men between 17 and 28 years old underwent noninvasive evaluation of systemic hemodynamics (impedance cardiography) and pulse wave analysis (SphygmoCor). Subjects were divided into 3 predefined groups of brachial PP: < 50, 50-64, and > or = 65 mmHg. The brachial-central PP difference increased with increasing brachial PP (17 +/- 4, 22 +/- 4, and 29 +/- 4 mmHg, respectively P < 0.001). In contrast, peripheral amplification (as measured by the brachial:central PP ratio) remained constant among the tree groups, at the expense of a concomitant widening of aortic PP (P < 0.001) without difference in augmentation index. In the entire sample, central and brachial PP, and the difference between the two measures, correlated positively with cardiac output (P < 0.001) and stroke volume (P < 0.01), and negatively with systemic vascular resistance (P < 0.001), without significant relationship with heart rate. In conclusion, despite the different amplitude, central and brachial PP shared common hemodynamic determinants. A high PP among young men underlied a high output-low resistance circulatory pattern, independently of the site of measurement. PMID:15132298

  16. PREDICTING RADIATION-INDUCED VALVULAR HEART DAMAGE

    PubMed Central

    Cella, Laura; Oh, Jung Hun; Deasy, Joseph O; Palma, Giuseppe; Liuzzi, Raffaele; D’Avino, Vittoria; Conson, Manuel; Picardi, Marco; Salvatore, Marco; Pacelli, Roberto

    2016-01-01

    Background To develop a predictive multivariate normal tissue complication probability (NTCP) model for radiation-induced heart valvular damage (RVD). The influence of combined heart-lung irradiation on RVD development was included. Methods and Materials Multivariate logistic regression modeling with the least absolute shrinkage and selection operator (LASSO) was used to build an NTCP model to predict RVD based on a cohort of 90 Hodgkin lymphoma patients treated with sequential chemo-radiation therapy. In addition to heart irradiation factors, clinical variables, along with left and right lung dose-volume histogram statistics, were included in the analysis. To avoid overfitting, 10-fold cross validation (CV) was used for LASSO logistic regression modeling, with 50 reshuffled cycles. Model performance was assessed using the area under the receiver operating characteristic (ROC) curve (AUC) and Spearman’s correlation coefficient (Rs). Results At a median follow-up time of 55 months (range, 12–92 months) after the end of radiation treatment, twenty-seven out of 90 patients (30%) manifested at least one kind of RVD (mild or moderate), with a higher incidence of left-sided valve defects (64%). Fourteen prognostic factors were frequently selected (more than 100/500 model fits) by LASSO, which included mainly heart and left lung dosimetric variables along with their volume variables. The averaged cross-validated performance was AUC-CV = 0.685 and Rs = 0.293. The overall performance of a final NTCP model for RVD obtained applying LASSO logistic regression to the full dataset was satisfactory (AUC= 0.84, Rs= 0.55, p < 0.001). Conclusion LASSO proved to be an improved and flexible modeling method for variable selection. Applying LASSO, we showed, for the first time, the importance of jointly considering left lung irradiation and left lung volume size in the prediction of subclinical radiation related heart disease resulting in RVD. PMID:25800857

  17. 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.

  18. Brachial plexus injuries in adults: evaluation and diagnostic approach.

    PubMed

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

    2014-01-01

    The increased incidence of motor vehicle accidents during the past century has been associated with a significant increase in brachial plexus injuries. New imaging studies are currently available for the evaluation of brachial plexus injuries. Myelography, CT myelography, and magnetic resonance imaging (MRI) are indicated in the evaluation of brachial plexus. Moreover, a series of specialized electrodiagnostic and nerve conduction studies in association with the clinical findings during the neurologic examination can provide information regarding the location of the lesion, the severity of trauma, and expected clinical outcome. Improvements in diagnostic approaches and microsurgical techniques have dramatically changed the prognosis and functional outcome of these types of injuries. PMID:24967130

  19. Brachial Plexus Injuries in Adults: Evaluation and Diagnostic Approach

    PubMed Central

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

    2014-01-01

    The increased incidence of motor vehicle accidents during the past century has been associated with a significant increase in brachial plexus injuries. New imaging studies are currently available for the evaluation of brachial plexus injuries. Myelography, CT myelography, and magnetic resonance imaging (MRI) are indicated in the evaluation of brachial plexus. Moreover, a series of specialized electrodiagnostic and nerve conduction studies in association with the clinical findings during the neurologic examination can provide information regarding the location of the lesion, the severity of trauma, and expected clinical outcome. Improvements in diagnostic approaches and microsurgical techniques have dramatically changed the prognosis and functional outcome of these types of injuries. PMID:24967130

  20. Radiation-induced charge trapping in bipolar base oxides

    SciTech Connect

    Fleetwood, D.M.; Riewe, L.C.; Witczak, Schrimpf, R.D.

    1996-03-01

    Capacitance-voltage and thermally stimulated current methods are used to investigate radiation induced charge trapping in bipolar base oxides. Results are compared with models of oxide and interface trap charge buildup at low electric fields.

  1. Treatment of radiation-induced cystitis with hyperbaric oxygen

    SciTech Connect

    Weiss, J.P.; Boland, F.P.; Mori, H.; Gallagher, M.; Brereton, H.; Preate, D.L.; Neville, E.C.

    1985-08-01

    The effects of hyperbaric oxygen on radiation cystitis have been documented in 3 patients with radiation-induced hemorrhagic cystitis refractory to conventional therapy. Cessation of gross hematuria and reversal of cystoscopic bladder changes were seen in response to a series of hyperbaric oxygen treatments of 2 atmosphere absolute pressure for 2 hours. To our knowledge this is the first report of cystoscopically documented healing of radiation-induced bladder injury.

  2. Characterization of radiation-induced Apoptosis in rodent cell lines

    SciTech Connect

    Guo, Min; Chen, Changhu; Ling, C.C.

    1997-03-01

    For REC:myc(ch1), Rat1 and Rat1:myc{sub b} cells, we determined the events in the development of radiation-induced apoptosis to be in the following order: cell division followed by chromatin condensation, membrane blebbing, loss of adhesion and the uptake of vital dye. Experimental data which were obtained using {sup 4}He ions of well defined energies and which compared the dependence of apoptosis and clonogenic survival on {sup 4}He range strongly suggested that in our cells both apoptosis and loss of clonogenic survival resulted from radiation damage to the cell nucleus. Corroboratory evidence was that BrdU incorporation sensitized these cells to radiation-induced apoptosis. Comparing the dose response for apoptosis and the clonogenic survival curves for Rat1 and Rat1:myc{sub b} cells, we concluded that radiation-induced cell inactivation as assayed by clonogenic survival, and that a modified linear-quadratic model, proposed previously, modeled such a contribution effectively. In the same context, the selective increase in radiation-induced apoptosis. Comparing the dose response for apoptosis and the clonogenic survival curves for Rat1 and Rat1:myc{sub b} cells, we concluded that radiation-induced apoptosis contributed to the overall radiation-induced cell inactivation as assayed by clonogenic survival, and that a modified linear-quadratic model, proposed previously, modeled such a contribution effectively. In the same context, the selective increase in radiation-induced apoptosis during late S and G{sub 2} phases reduced the relative radioresistance observed for clonogenic survival during late S and G{sub 2} phases. 30 refs., 8 figs.

  3. 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

  4. 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. PMID:21091763

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

    MedlinePlus

    ... Artery Disease and Cardiovascular Disease Risk Assessment with Ankle Brachial Index in Adults The U.S. Preventive Services ... PAD) and Cardiovascular Disease (CVD) Risk Assessment with Ankle Brachial Index (ABI) in Adults . This final recommendation ...

  6. Radiation-induced localized scleroderma in breast cancer patients.

    PubMed

    Bleasel, N R; Stapleton, K M; Commens, C; Ahern, V A

    1999-05-01

    Radiation-induced scleroderma in breast cancer patients appears to occur in approximately one out of every 500 patients. We report four cases that developed within 3 months of conservative breast surgery and postoperative radiation treatment. The reaction was contained entirely within the treatment field and demonstrated the typical features of this condition where the breast becomes erythematous, violaceous, indurated, retracted, and progressively pigmented. The breast tends to soften and become more comfortable over 1-4 years; however, significant induration, retraction and pigmentary changes remain. There appears to be no predictive factors. Radiation-induced scleroderma must be differentiated from cellulitis and recurrent breast cancer. PMID:10333622

  7. 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.

  8. Hyperbaric oxygen: Primary treatment of radiation-induced hemorrhagic cystitis

    SciTech Connect

    Weiss, J.P.; Neville, E.C.

    1989-07-01

    Of 8 patients with symptoms of advanced cystitis due to pelvic radiation treated with hyperbaric oxygen 7 are persistently improved during followup. All 6 patients treated for gross hematuria requiring hospitalization have been free of symptoms for an average of 24 months (range 6 to 43 months). One patient treated for stress incontinence currently is dry despite little change in bladder capacity, implying salutary effect from hyperbaric oxygen on the sphincter mechanism. One patient with radiation-induced prostatitis failed to respond. This experience suggests that hyperbaric oxygen should be considered the primary treatment for patients with symptomatic radiation-induced hemorrhagic cystitis.

  9. Mechanistic issues for modeling radiation-induced segregation

    SciTech Connect

    Simonen, E.P.; Bruemmer, S.M.

    1993-03-01

    Model calculations of radiation-induced chromium depletion and radiation-induced nickel enrichment at grain boundaries are compared to measured depletions and enrichments. The model is calibrated to fit chromium depletion in commercial purity 304 stainless steel irradiated in boiling water reactor (BWR) environments. Predicted chromium depletion profiles and the dose dependence of chromium concentration at grain boundaries are in accord with measured trends. Evaluation of chromium and nickel profiles in three neutron, and two ion, irradiation environments reveal significant inconsistencies between measurements and predictions.

  10. Brachial Artery Access for Percutaneous Renal Artery Interventions

    SciTech Connect

    Kaukanen, Erkki T.; Manninen, Hannu I.; Matsi, Pekka J.; Soeder, Heini K.

    1997-09-15

    Purpose: To evaluate the suitability of transbrachial access for endovascular renal artery interventions. Methods: During 37 consecutive endovascular renal artery interventions, the transbrachial approach was used on nine patients (mean age 63 years; range 41-76 years) for 11 renal artery procedures on native kidneys and one percutaneous transluminal angioplasty (PTA) on a transplanted kidney. The reason for using transbrachial access was a steep aorta-renal angle in five, and severe aorta-iliac atherosclerosis in the remaining patients. In addition to the intervention catheter in the left brachial artery, an additional nonselective catheter for controlling the procedure was inserted transfemorally (six patients) or via the contralateral brachial artery. Results: Eleven interventions (six PTAs, five stents) were successfully completed. The one failure resulted from impenetrable subclavian artery stenosis. The only major complication was a brachial artery pseudoaneurysm requiring surgical treatment. Conclusion: Transbrachial access is an effective and relatively safe technique for renal artery interventions when transfemoral access is not possible.

  11. 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.

  12. 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.

  13. SENSITIVITY TO RADIATION-INDUCED CANCER IN HEMOCHROMATOSIS

    EPA Science Inventory

    Determination of dose-response relationships for radiation-induced cancer in segments of the population with high susceptibility is critical for understanding the risks of low dose and low dose rates to humans. Clean-up levels for radionuclides will depend upon the fraction of t...

  14. 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.

  15. [Symptoms and treatment of radiation-induced reactions].

    PubMed

    Brzozowska, Anna; Idziak, Magdalena; Burdan, Franciszek; Mazurkiewicz, Maria

    2015-05-01

    Radiotherapy is one of the main methods of cancer treatment alone or in combination with chemotherapy. It is applied in about 60% of oncological patients. However, in spite of its clinical usefulness, radiotherapy is associated with a high risk of radiation-induced side effects, including dermatitis, enteritis, cystitis, pericarditis, pneumonia or depression, sexual function disorders, cardiomiopathy, coronary heart disease, anomalies of heart valves and development of second malignant tumor. The early diagnosis and proper treatment of radiation-induced side effects have a major impact on patients` quality of life and future prognosis. Radiation reactions can be categorized as acute or late, occurring before and after six months after radiotherapy. Among the most common acute reactions there were observed: skin rash, mucositis, nausea, vomiting, fever and radiation pneumonitis. Within reference to the late complications, we distinguish for instance fibrosis of organs, a radiation necrosis of bone, ulcers, fistulas, sexual dysfunction and the development of second malignant carcinomas. PMID:26039025

  16. Biological determinants of radiation-induced human breast cancer

    SciTech Connect

    Feig, S.A.

    1980-01-01

    This is the second in a three part series on the hypothetical risk from x-ray mammography. It will review those aspects of breast anatomy, histology, physiology, and pathology which are pertinent to radiation carcinogenesis. Radiation-induced breast cancers are histologically identical to the naturally occurring type in that they arise from the ductal epithelium and consist of a similar proportion of infiltrating and intraductal lesions. Possible explanations for the increased resistance to radiation effect in women over 30 years of age at time of exposure include regression of the glandular target tissue, hormonal changes, and parity. Examples of age-related sensitivity and hormonal dependence in other radiation-induced human and animal tumors will be discussed.

  17. Radiation-induced transient absorption in single mode optical fibers

    SciTech Connect

    Looney, L.D.; Lyons, P.B.

    1988-01-01

    This paper reviews the measurements conducted by the Los Alamos National Laboratory in support of these NATO efforts wherein radiation-induced transient absorption was measured over time ranges from a few ns to several ..mu..s for two single mode fibers. Experimental conditions were varied to provide data for future development of standarized test conditions for single mode fibers. 8 refs., 11 figs.

  18. 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.

  19. 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.

  20. 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.

  1. 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

  2. Mast Cells Contribute to Radiation-Induced Vascular Hyperpermeability

    PubMed Central

    Park, Kyung Ran; Monsky, Wayne L.; Lee, Chang Geol; Song, Chang Ho; Kim, Dong Heui; Jain, Rakesh K.; Fukumura, Dai

    2016-01-01

    Induction of vascular hyperpermeability is one of the early vascular responses to radiation exposure and is considered to contribute to subsequent fibrosis and tissue injuries. However, the mechanism underlying radiation-induced hyperpermeability has not yet been clearly elucidated. Here, we provide experimental evidence indicating that mast cells contribute to the increase in vascular permeability for albumin in normal mouse skin after irradiation. Vascular permeability in the skin of C3H mice increased after 2, 15 and 50 Gy irradiation, peaked at 24 h after irradiation and gradually decreased thereafter to the baseline level within 3–10 days. Both the extent and duration of hyperpermeability were dose dependent. We found significant degranulation of mast cells in the skin after 15 Gy irradiation. To further investigate the role of mast cells in the radiation-induced increase in vascular permeability, we measured vascular permeability in the skin of mast cell-deficient mice (WWv) and their wild-type littermates at 24 h after irradiation. Vascular permeability in WWv mice did not change, whereas that in wild-type mice significantly increased after irradiation. There were no appreciable changes in the total tissue levels of vascular endothelial growth factor or endothelial nitric oxide synthase after 15 Gy irradiation and there was no detectable expression of inducible nitric oxide synthase. Collectively, these results show that exposure to radiation induces vascular hyperpermeability in a dose-dependent manner and that mast cells contribute to this process. PMID:26771172

  3. Transplantation of human amniotic epithelial cells repairs brachial plexus injury: pathological and biomechanical analyses

    PubMed Central

    Yang, Qi; Luo, Min; Li, Peng; Jin, Hai

    2014-01-01

    A brachial plexus injury model was established in rabbits by stretching the C6 nerve root. Immediately after the stretching, a suspension of human amniotic epithelial cells was injected into the injured brachial plexus. The results of tensile mechanical testing of the brachial plexus showed that the tensile elastic limit strain, elastic limit stress, maximum stress, and maximum strain of the injured brachial plexuses were significantly increased at 24 weeks after the injection. The treatment clearly improved the pathological morphology of the injured brachial plexus nerve, as seen by hematoxylin eosin staining, and the functions of the rabbit forepaw were restored. These data indicate that the injection of human amniotic epithelial cells contributed to the repair of brachial plexus injury, and that this technique may transform into current clinical treatment strategies. PMID:25657737

  4. Brachial artery aneurysm accompanying a homozygous methylenetetrahydrofolate reductase mutation

    PubMed Central

    Guler, Adem; Tavlasoglu, Murat; Arslan, Zekeriya; Yesil, Fahri Gurkan

    2013-01-01

    Elevated plasma homocysteine (Hcy) is one of the suggested risk factors for endothelial dysfunction. There is evidence of association between raised plasma Hcy and an increased risk of developing peripheral arterial disease. A causal relationship, however, has not been established. In this report, a 37-year old male patient with the complaints of intermittent hand pain is presented. Brachial artery aneurysm accompanying a homozygous methylenetetrahydrofolate reductase mutation was detected. PMID:23460600

  5. Aortic-brachial stiffness mismatch and mortality in dialysis population.

    PubMed

    Fortier, Catherine; Mac-Way, Fabrice; Desmeules, Simon; Marquis, Karine; De Serres, Sacha A; Lebel, Marcel; Boutouyrie, Pierre; Agharazii, Mohsen

    2015-02-01

    We hypothesized that increased aortic stiffness (central elastic artery) combined with a decrease in brachial stiffness (peripheral muscular artery) leads to the reversal of the physiological stiffness gradient (ie, mismatch), promoting end-organ damages through increased forward pressure wave transmission into the microcirculation. We, therefore, examined the effect of aortic-brachial stiffness mismatch on mortality in patients in need of dialysis. In a prospective observational study, aortic-brachial arterial stiffness mismatch (pulse wave velocity ratio) was assessed using carotid-femoral pulse wave velocity divided by carotid-radial pulse wave velocity in 310 adult patients on dialysis. After a median follow-up of 29 months, 146 (47%) deaths occurred. The hazard ratio (HR) for mortality related to PWV ratio in a Cox regression analysis was 1.43 (95% confidence interval [CI], 1.24-1.64; P<0.001 per 1 SD) and was still significant after adjustments for confounding factors, such as age, dialysis vintage, sex, cardiovascular disease, diabetes mellitus, smoking status, and weight (HR, 1.23; 95% CI: 1.02-1.49). The HRs for changes in 1 SD of augmentation index (HR, 1.35; 95% CI, 1.12-1.63), carotid-femoral pulse wave velocity (HR, 1.29; 95% CI, 1.11-1.50), and carotid-radial pulse wave velocity (HR, 0.80; 95% CI, 0.67-0.95) were statistically significant in univariate analysis, but were no longer statistically significant after adjustment for age. In conclusion, aortic-brachial arterial stiffness mismatch was strongly and independently associated with increased mortality in this dialysis population. Further studies are required to confirm these finding in lower-risk groups. PMID:25452473

  6. Quantifying Local Radiation-Induced Lung Damage From Computed Tomography

    SciTech Connect

    Ghobadi, Ghazaleh; Hogeweg, Laurens E.; Brandenburg, Sytze; Langendijk, Johannes A.

    2010-02-01

    Purpose: Optimal implementation of new radiotherapy techniques requires accurate predictive models for normal tissue complications. Since clinically used dose distributions are nonuniform, local tissue damage needs to be measured and related to local tissue dose. In lung, radiation-induced damage results in density changes that have been measured by computed tomography (CT) imaging noninvasively, but not yet on a localized scale. Therefore, the aim of the present study was to develop a method for quantification of local radiation-induced lung tissue damage using CT. Methods and Materials: CT images of the thorax were made 8 and 26 weeks after irradiation of 100%, 75%, 50%, and 25% lung volume of rats. Local lung tissue structure (S{sub L}) was quantified from local mean and local standard deviation of the CT density in Hounsfield units in 1-mm{sup 3} subvolumes. The relation of changes in S{sub L} (DELTAS{sub L}) to histologic changes and breathing rate was investigated. Feasibility for clinical application was tested by applying the method to CT images of a patient with non-small-cell lung carcinoma and investigating the local dose-effect relationship of DELTAS{sub L}. Results: In rats, a clear dose-response relationship of DELTAS{sub L} was observed at different time points after radiation. Furthermore, DELTAS{sub L} correlated strongly to histologic endpoints (infiltrates and inflammatory cells) and breathing rate. In the patient, progressive local dose-dependent increases in DELTAS{sub L} were observed. Conclusion: We developed a method to quantify local radiation-induced tissue damage in the lung using CT. This method can be used in the development of more accurate predictive models for normal tissue complications.

  7. A Perplexing Presentation of Entrapment of the Brachial Artery

    PubMed Central

    Cevirme, Deniz; Aksoy, Eray; Adademir, Taylan; Sunar, Hasan

    2015-01-01

    A 45-year-old male being otherwise healthy presented acute onset of right upper extremity ischemia. On physical examination, axillary artery could be palpated whereas the brachial artery could not be palpated below the level of the antecubital fossa, including radial and ulnar artery pulses. Pulses were also inaudible with pocket-ultrasound below the level of the brachial artery bifurcation. The patient was initially diagnosed to have acute thromboembolic occlusion and given 5000 IU intravenous heparin. The patient was taken to the operating room. We noticed that the ischemic symptoms disappeared within a couple of minutes just before we began the operation. However, ischemic symptoms reappeared six hours later and computed tomography angiography showed lack of enhancement below the elbow crease. We were taking the patient to the operating room for the second time when the symptoms recovered in a few minutes, again. The operation was not canceled anymore. In the operation, the brachial artery was found anomalously perforating and it was entrapped by the bicipital aponeurosis. The artery was relieved by resecting the aponeurosis and there was no need for any other intervention. The patient had no more recurrence of symptoms postoperatively. PMID:26185707

  8. Dcompression chirurgicale du syndrome de dfil thoraco-brachial

    PubMed Central

    Lukulunga, Loubet Unyendje; Moussa, Abdou Kadri; Mahfoud, Mustapha; Ismael, Farid; Berrada, Mohamed Saleh; El Yaacoubi, Moradh

    2014-01-01

    Le syndrome de dfil thoraco-brachial est une pathologie souvent mconnue cause de diagnostic difficile par manque des signes pathognomoniques conduisant souvent des errances. Les manifestations cliniques dpendent selon qu'il s'agit d'une compression nerveuse, vasculaire ou vasculo-nerveuse. Le but de cette tude est de dcrire certains aspects cliniques particuliers et valuer le rsultat fonctionnel aprs la dcompression chirurgicale du paquet vasculo-nerveux. Notre tude rtrospective a port sur l'analyse des donnes cliniques, radiologiques, IRM et EMG sur les patients oprs entre janvier 2010 et juillet 2013 du syndrome de dfil thoraco-brachial dans le service de traumatologie orthopdie de l'hpital Ibn Sina de Rabat. 15 cas ont t colligs: 12 cas post traumatiques (fracture de la clavicule) et 3 cas d'origines congnitales, dont lge moyen tait 35 ans (20 50 ans) avec 9 femmes et 6 hommes. A la fin du traitement, le score de Dash est pass de 109 (46% Normal=0) 70 (20%), et le stress test de Roos tait de 70/100 80/100. Le rsultat tait excellent dans 12 cas soit (80%) et moins bon dans dans 3 cas (20%). En dfinitive, la rsection de malformations osseuses, l'excision des brides et la neurolyse du plexus brachial suivie de la rducation a donn une bonne volution fonctionnelle. PMID:25709735

  9. Transient radiation-induced absorption in laser materials

    SciTech Connect

    Brannon, P.J.

    1994-12-31

    Transient radiation-induced absorption losses in laser materials have been measured using a pulsed nuclear reactor. Reactor pulse widths of 70 to 90 {mu}s and absorbed doses of 1 to 7.5 krad have been used. Transmission recovery times and peak absorption coefficients are given. Materials tested include LiNbO{sub 3}, GSGG, silica substrates, and filter glasses used in the laser cavity. The filter glasses are tested at discrete wavelengths in the range 440--750 nm. Lithium niobate , MgO doped LiNbO{sub 3}, GSGG, and the silica substrates are tested at 1061 nm.

  10. 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.

  11. 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.

  12. 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.

  13. Management of radiation-induced accelerated carotid atherosclerosis

    SciTech Connect

    Loftus, C.M.; Biller, J.; Hart, M.N.; Cornell, S.H.; Hiratzka, L.F.

    1987-07-01

    Patients with long survival following cervical irradiation are at risk for accelerated carotid atherosclerosis. The neurologic presentation in these patients mimics naturally occurring atheromatous disease, but patients often present at younger ages and with less concurrent coronary or systemic vascular disease. Hypercholesterolemia also contributes to this accelerated arteriosclerosis. Angiographic findings in this disorder include disproportionate involvement of the distal common carotid artery and unusually long carotid lesions. Pathologic findings include destruction of the internal elastic lamina and replacement of the normal intima and media with fibrous tissue. This article describes two surgical patients with radiation-induced accelerated carotid atherosclerosis who typify the presentation and characteristics of this disease.

  14. Radiation induced corrosion of copper for spent nuclear fuel storage

    NASA Astrophysics Data System (ADS)

    Björkbacka, Åsa; Hosseinpour, Saman; Johnson, Magnus; Leygraf, Christofer; Jonsson, Mats

    2013-11-01

    The long term safety of repositories for radioactive waste is one of the main concerns for countries utilizing nuclear power. The integrity of engineered and natural barriers in such repositories must be carefully evaluated in order to minimize the release of radionuclides to the biosphere. One of the most developed concepts of long term storage of spent nuclear fuel is the Swedish KBS-3 method. According to this method, the spent fuel will be sealed inside copper canisters surrounded by bentonite clay and placed 500 m down in stable bedrock. Despite the importance of the process of radiation induced corrosion of copper, relatively few studies have been reported. In this work the effect of the total gamma dose on radiation induced corrosion of copper in anoxic pure water has been studied experimentally. Copper samples submerged in water were exposed to a series of total doses using three different dose rates. Unirradiated samples were used as reference samples throughout. The copper surfaces were examined qualitatively using IRAS and XPS and quantitatively using cathodic reduction. The concentration of copper in solution after irradiation was measured using ICP-AES. The influence of aqueous radiation chemistry on the corrosion process was evaluated based on numerical simulations. The experiments show that the dissolution as well as the oxide layer thickness increase upon radiation. Interestingly, the evaluation using numerical simulations indicates that aqueous radiation chemistry is not the only process driving the corrosion of copper in these systems.

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

    DOE PAGESBeta

    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

  16. Characterization of radiation-induced emesis in the ferret

    SciTech Connect

    King, G.L.

    1988-06-01

    Forty-eight ferrets (Mustela putorius furo) were individually head-shielded and radiated with bilateral /sup 60/Co gamma radiation at 100 cGy min-1 at doses ranging between 49 and 601 cGy. The emetic threshold was observed at 69 cGy, the ED50 was calculated at 77 cGy, and 100% incidence of emesis occurred at 201 cGy. With increasing doses of radiation, the latency to first emesis after radiation decreased dramatically, whereas the duration of the prodromal period increased. Two other sets of experiments suggest that dopaminergic mechanisms play a minor role in radiation-induced emesis in the ferret. Twenty-two animals were injected either intravenously or subcutaneously with 30 to 300 micrograms/kg of apomorphine. Fewer than 50% of the animals vomited to 300 micrograms/kg apomorphine; central dopaminergic receptor activation was apparent at all doses. Another eight animals received 1 mg/kg domperidone prior to either 201 (n = 4) or 401 (n = 4) cGy radiation and their emetic responses were compared with NaCl-injected-irradiated controls (n = 8). At 201 cGy, domperidone significantly reduced only the total time in emetic behavior. At 401 cGy, domperidone had no salutary effect on radiation-induced emesis. The emetic responses of the ferret to radiation and apomorphine are compared with these responses in other vomiting species.

  17. Characterization of radiation-induced emesis in the ferret

    SciTech Connect

    King, G.L.

    1988-01-01

    Forty-eight ferrets (Mustela putorius furo) were individually head-shielded and radiated with bilateral cobalt 60 gamma radiation at 100 cGy min at doses ranging between 49 and 601 cGy. The emetic threshold was observed at 69 cGy, the ED 50 was calculated as 77 cGy, and 100% incidence of emesis occurred at 201 cGy. With increasing doses of radiation, the latency to first emesis after radiation decreased dramatically, whereas the duration of the prodromal period increased. Two other sets of experiments suggest that dopaminergic mechanisms play a minor role in radiation-induced emesis in the ferret. Twenty-two animals were injected either intravenously or subcutaneously with 30 to 300 micrograms /kg of apomorphine. Fewer than 50% of the animals vomited to 300 micrograms/kg apomorphine; central dopaminergic receptor activation was apparent at all doses. Another eight animals received 1 mg/kg domperidone prior to either 201 (n=4) or 401 (n=4) cGy radiation and their emetic responses were compared with NaCi-injected-irradiated controls (n=8). At 201 cGy, domperidone significantly reduced only the total time in emetic behavior. At 401 cGy, domperidone had no salutary effect on radiation-induced emesis. The emetic responses of the ferret to radiation and apomorphine are compared with these responses in other vomiting species.

  18. Radiation-induced defect centers in glass ceramics

    NASA Astrophysics Data System (ADS)

    Tsai, T. E.; Friebele, E. J.; Griscom, D. L.; Pannhorst, W.

    1989-01-01

    Electron spin resonance (ESR) was used to characterize the radiation-induced defect centers in low-thermal-expansion glass ceramics, including two types of Zerodur and Astrositall. The observed ESR spectra can be associated with different types of defect centers: a Zn+ center, several types of oxygen hole centers (OHCs), an aluminum-oxygen hole center (Al-OHC), an Fe3+ center, Ti3+ and Zr3+ centers, and three types of As centers. An Sb4+ center, which is not observed in Zerodur, is tentatively identified in Astrositall. From the effect of crystallization on the observed defect concentrations in Zerodur and computer simulation of the spectral lines of some of the centers, we infer that among the nine defect centers observed in the Zerodurs, the As-associated centers are located in the glassy phase and/or at the interface between the glassy and crystalline phases, Zn+ and Al-OHC are in the crystalline phase, and the rest (including most of the OHCs) are in the glassy phase. Radiation-induced compaction in these materials appears to be related to the generation of OHCs in the glass phase.

  19. Radiation-induced defect centers in glass ceramics

    SciTech Connect

    Tsai, T.E.; Friebele, E.J.; Griscom, D.L.; Pannhorst, W.

    1989-01-15

    Electron spin resonance (ESR) was used to characterize the radiation-induced defect centers in low-thermal-expansion glass ceramics, including two types of Zerodur and Astrositall. The observed ESR spectra can be associated with different types of defect centers: a Zn/sup +/ center, several types of oxygen hole centers (OHCs), an aluminum-oxygen hole center (Al-OHC), an Fe/sup 3 +/ center, Ti/sup 3 +/ and Zr/sup 3 +/ centers, and three types of As centers. An Sb/sup 4 +/ center, which is not observed in Zerodur, is tentatively identified in Astrositall. From the effect of crystallization on the observed defect concentrations in Zerodur and computer simulation of the spectral lines of some of the centers, we infer that among the nine defect centers observed in the Zerodurs, the As-associated centers are located in the glassy phase and/or at the interface between the glassy and crystalline phases, Zn/sup +/ and Al-OHC are in the crystalline phase, and the rest (including most of the OHCs) are in the glassy phase. Radiation-induced compaction in these materials appears to be related to the generation of OHCs in the glass phase.

  20. 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.

  1. 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.

  2. 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.

  3. 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.

  4. 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.

  5. 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.

  6. 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.

  7. Delayed Diagnosis of Probable Radiation Induced Spinal Cord Vascular Disorders

    PubMed Central

    Won, Young Il; Chung, Chun Kee; Yun, Tae Jin

    2015-01-01

    Occasionally, unexpected neurological deficits occur after lumbar spinal surgery. We report a case of monoparesis after lumbar decompressive surgery. A 63-year-old man, who had undergone decompression of L4-5 for spinal stenosis 4 days previously in the other hospital, visted the emergency department with progressive weakness in the left leg and hypoesthesia below sensory level T7 on the right side. He had been cured of lung cancer with chemotherapy and radiation therapy 10 years previously, but detailed information of radiotherapy was not available. Whole spine magnetic resonance (MR) imaging showed fatty marrow change from T1 to T8, most likely due to previous irradiation. The T2-weighted MR image showed a high-signal T4-5 spinal cord lesion surrounded by a low signal rim, and the T1-weighted MR image showed focal high signal intensity with focal enhancement. The radiological diagnosis was vascular disorders with suspicious bleeding. Surgical removal was refused by the patient. With rehabilitation, the patient could walk independently without assistance 2 months later. Considering radiation induced change at thoracic vertebrae, vascular disorders may be induced by irradiation. If the spinal cord was previously irradiated, radiation induced vascular disorders needs to be considered. PMID:25810864

  8. 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 cells during genome reprogramming by the oncogene c-myc and three additional transcription factors. These and other data reveal the need for generalisation of current model of GI. One can expect that different early events of both DNA damaging and non-damaging origins merge in a single late pathway. To search for a deeper view we propose to redefine GI as genome destabilisation manifested in erosion of genome states and altered transitions between states. This changing view on GI may help to integrate the inducing factors of various origins in the single basic model of GI.

  9. Anatomical Variations of Brachial Artery - Its Morphology, Embryogenesis and Clinical Implications

    PubMed Central

    KS, Siddaraju; Venumadhav, Nelluri; Sharma, Ashish; Kumar, Neeraj

    2014-01-01

    Background: Accurate knowledge of variation pattern of the major arteries of upper limb is of considerable practical importance in the conduct of reparative surgery in the arm, forearm and hand however brachial artery and its terminal branches variations are less common. Aim: Accordingly the present study was designed to evaluate the anatomical variations of the brachial artery and its morphology, embryogenesis and clinical implications. Materials and Methods: In an anatomical study 140 upper limb specimens of 70 cadavers (35 males and 35 females) were used and anatomical variations of the brachial artery have been documented. Results: Accessory brachial artery was noted in eight female cadavers (11.43%). Out of eight cadavers in three cadavers (4.29%) an unusual bilateral accessory brachial artery arising from the axillary artery and it is continuing in the forearm as superficial accessory ulnar artery was noted. Rare unusual variant unilateral accessory brachial artery and its reunion with the main brachial artery in the cubital fossa and its variable course in relation to the musculocutaneous nerve and median nerve were also noted in five cadavers (7.14%). Conclusion: As per our knowledge such anatomical variations of brachial artery and its terminal branches with their relation to the surrounding structures are not reported in the modern medical literature. An awareness of such a presence is valuable for the surgeons and radiologists in evaluation of angiographic images, vascular and re-constructive surgery or appropriate treatment for compressive neuropathies. PMID:25653931

  10. Percutaneous Extraluminal (Subintimal) Recanalization of a Brachial Artery Occlusion Following Cardiac Catheterization

    SciTech Connect

    Bolia, Amman; Nasim, Akhtar; Bell, Peter R.F.

    1996-05-15

    A 47-year-old woman presented with disabling right arm claudication 10 weeks after Sones cardiac catheterization via a brachial artery cut-down. A technique of extraluminal recanalization of the brachial artery occlusion, used to treat this patient, is described.

  11. Penile erectile dysfunction after brachial plexus root avulsion injury in rats

    PubMed Central

    Fu, Guo; Qin, Bengang; Jiang, Li; Huang, Xijun; Lu, Qinsen; Zhang, Dechun; Liu, Xiaolin; Zhu, Jiakai; Zheng, Jianwen; Li, Xuejia; Gu, Liqiang

    2014-01-01

    Our previous studies have demonstrated that some male patients suffering from brachial plexus injury, particularly brachial plexus root avulsion, show erectile dysfunction to varying degrees. However, the underlying mechanism remains poorly understood. In this study, we evaluated the erectile function after establishing brachial plexus root avulsion models with or without spinal cord injury in rats. After these models were established, we administered apomorphine (via a subcutaneous injection in the neck) to observe changes in erectile function. Rats subjected to simple brachial plexus root avulsion or those subjected to brachial plexus root avulsion combined with spinal cord injury had significantly fewer erections than those subjected to the sham operation. Expression of neuronal nitric oxide synthase did not change in brachial plexus root avulsion rats. However, neuronal nitric oxide synthase expression was significantly decreased in brachial plexus root avulsion + spinal cord injury rats. These findings suggest that a decrease in neuronal nitric oxide synthase expression in the penis may play a role in erectile dysfunction caused by the combination of brachial plexus root avulsion and spinal cord injury. PMID:25422647

  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. 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.

  14. 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.

  15. Pyridoxamine protects intestinal epithelium from ionizing radiation-induced apoptosis

    PubMed Central

    Thotala, Dinesh; Chetyrkin, Sergei; Hudson, Billy; Hallahan, Dennis; Voziyan, Paul; Yazlovitskaya, Eugenia

    2009-01-01

    Reactive oxygen species (ROS) and reactive carbonyl species (RCS) are the major cause of biological tissue damage during the exposure to ionizing radiation (IR). The existing strategies to protect normal tissues from detrimental effects of IR suffer from several shortcomings including high toxic side effects, unfavorable administration routs or low efficacy. These shortcomings emphasize a need for radioprotective treatments that combine effectiveness with safety and ease of use. In this paper, we demonstrate that pyridoxamine, a ROS and RCS scavenger with a very favorable safety profile, can inhibit IR-induced gastrointestinal endothelial apoptosis in cell culture and in animal model. Pyridoxamine was more effective at protecting from radiation-induced apoptosis compared to Amifostine, a synthetic thiol compound and the only FDA approved radioprotector. We suggest that PM has a potential as an effective and safe radioprotective agent. PMID:19540915

  16. Dose-dependent radiation-induced hypotension in the canine

    SciTech Connect

    Cockerham, L.G.; Hampton, J.D.; Doyle, T.F.

    1986-01-01

    Radiation-induced early transient incapacitation (ETI) is often accompanied by severe systemic hypotension. However, postradiation hypotension does not occur with equal frequency in all species and is not reported with consistency in the canine. In an attempt to clarify the differences in reported canine post-radiation blood pressures, canine systemic blood pressures were determined both before and after exposure to gamma radiation of either 80 or 100 Gy. Data obtained from six sham-radiated beagles and 12 radiated beagles indicated that 100-Gy, whole-body, gamma radiation produced a decrease in systemic mean blood pressure while 80-Gy, whole-body, gamma radiation did not. Analysis of this data could be consistent with a quantal response to a gamma radiation dose between 80 Gy and 100 Gy.

  17. 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).

  18. A model of radiation-induced myelopoiesis in space.

    PubMed

    Esposito, R D; Durante, M; Gialanella, G; Grossi, G; Pugliese, M; Scampoli, P; Jones, T D

    2001-01-01

    Astronauts' radiation exposure limits are based on experimental and epidemiological data obtained on Earth. It is assumed that radiation sensitivity remains the same in the extraterrestrial space. However, human radiosensitivity is dependent upon the response of the hematopoietic tissue to the radiation insult. It is well known that the immune system is affected by microgravity. We have developed a mathematical model of radiation-induced myelopoiesis which includes the effect of microgravity on bone marrow kinetics. It is assumed that cellular radiosensitivity is not modified by the space environment, but repopulation rates of stem and stromal cells are reduced as a function of time in weightlessness. A realistic model of the space radiation environment, including the HZE component, is used to simulate the radiation damage. A dedicated computer code was written and applied to solar particle events and to the mission to Mars. The results suggest that altered myelopoiesis and lymphopoiesis in microgravity might increase human radiosensitivity in space. PMID:11771552

  19. 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.

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

    NASA Astrophysics Data System (ADS)

    Snchez, 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 ?-rays and the formation of the identified products are presented.

  1. 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.

  2. Imaging for Assessment of Radiation-Induced Normal Tissue Effects

    SciTech Connect

    Jeraj, Robert; Cao Yue; Ten Haken, Randall K.; Hahn, Carol; Marks, Lawrence

    2010-03-01

    Imaging can provide quantitative assessment of radiation-induced normal tissue effects. Identifying an early sign of normal tissue damage with imaging would have the potential to predict organ dysfunction, thereby allowing reoptimization of treatment strategies based on individual patients' risks and benefits. Early detection with noninvasive imaging may enable interventions to mitigate therapy-associated injury before its clinical manifestation. Furthermore, successive imaging may provide an objective assessment of the impact of such mitigation therapies. However, many problems make application of imaging to normal tissue assessment challenging, and further work is required to establish imaging biomarkers as surrogate endpoints of clinical outcome. The performance of clinical trials in which normal tissue injury is a clearly defined endpoint would greatly aid in realization of these goals.

  3. Imaging for assessment of radiation-induced normal tissue effects.

    PubMed

    Jeraj, Robert; Cao, Yue; Ten Haken, Randall K; Hahn, Carol; Marks, Lawrence

    2010-03-01

    Imaging can provide quantitative assessment of radiation-induced normal tissue effects. Identifying an early sign of normal tissue damage with imaging would have the potential to predict organ dysfunction, thereby allowing reoptimization of treatment strategies based on individual patients' risks and benefits. Early detection with noninvasive imaging may enable interventions to mitigate therapy-associated injury before its clinical manifestation. Furthermore, successive imaging may provide an objective assessment of the impact of such mitigation therapies. However, many problems make application of imaging to normal tissue assessment challenging, and further work is required to establish imaging biomarkers as surrogate endpoints of clinical outcome. The performance of clinical trials in which normal tissue injury is a clearly defined endpoint would greatly aid in realization of these goals. PMID:20171509

  4. 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.

  5. Solar radiation induced rotational bursting of interplanetary particles

    NASA Technical Reports Server (NTRS)

    Sparrow, J. G.

    1975-01-01

    It is suggested that the magnitudes of the two radiation-induced rotational bursting mechanisms (Radzieskii effect and windmill effect) have been overestimated and that they do not work significantly faster than the Poynting-Robertson effect in removing interplanetary particles. These two mechanisms are described, and serious doubts are raised regarding the derivation of their radiation pressure-torque proportionality constants, which are required for calculating their magnitudes. It is shown that both mechanisms will cause the alignment of elongated particles and, consequently, the polarization of zodiacal light. Since no positive polarization has been measured at the antisolar point, it is concluded that the magnitudes of the rotational bursting mechanisms are smaller than that of the Poynting-Robertson effect.

  6. Radiation-Induced Heart Disease: Pathologic Abnormalities and Putative Mechanisms

    PubMed Central

    Taunk, Neil K.; Haffty, Bruce G.; Kostis, John B.; Goyal, Sharad

    2015-01-01

    Breast cancer is a common diagnosis in women. Breast radiation has become critical in managing patients who receive breast conserving surgery, or have certain high-risk features after mastectomy. Most patients have an excellent prognosis, therefore understanding the late effects of radiation to the chest is important. Radiation-induced heart disease (RIHD) comprises a spectrum of cardiac pathology including myocardial fibrosis and cardiomyopathy, coronary artery disease, valvular disease, pericardial disease, and arrhythmias. Tissue fibrosis is a common mediator in RIHD. Multiple pathways converge with both acute and chronic cellular, molecular, and genetic changes to result in fibrosis. In this article, we review the pathophysiology of cardiac disease related to radiation therapy to the chest. Our understanding of these mechanisms has improved substantially, but much work remains to further refine radiation delivery techniques and develop therapeutics to battle late effects of radiation. PMID:25741474

  7. 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.

  8. 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 into the irradiated lung.

  9. 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.

  10. 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

    During prolonged spaceflight, astronauts are exposed to both microgravity and space radiation, and are at risk for increased skeletal fragility due to bone loss. Evidence from rodent experiments demonstrates that both microgravity and ionizing radiation can cause bone loss due to increased bone-resorbing osteoclasts and decreased bone-forming osteoblasts, although the underlying molecular mechanisms for these changes are not fully understood. We hypothesized that excess reactive oxidative species (ROS), produced by conditions that simulate spaceflight, alter the tight balance between osteoclast and osteoblast activities, leading to accelerated skeletal remodeling and culminating in bone loss. To test this, we used the MCAT mouse model; these transgenic mice over-express the human catalase gene targeted to mitochondria, the major organelle contributing free radicals. Catalase is an anti-oxidant that converts reactive species, hydrogen peroxide into water and oxygen. This animal model was selected as it displays extended lifespan, reduced cardiovascular disease and reduced central nervous system radio-sensitivity, consistent with elevated anti-oxidant activity conferred by the transgene. We reasoned that mice overexpressing catalase in mitochondria of osteoblast and osteoclast lineage cells would be protected from the bone loss caused by simulated spaceflight. Over-expression of human catalase localized to mitochondria caused various skeletal phenotypic changes compared to WT mice; this includes greater bone length, decreased cortical bone area and moment of inertia, and indications of altered microarchitecture. These findings indicate mitochondrial ROS are important for normal bone-remodeling and skeletal integrity. Catalase over-expression did not fully protect skeletal tissue from structural decrements caused by simulated spaceflight; however there was significant protection in terms of cellular oxidative damage (MDA levels) to the skeletal tissue. Furthermore, we 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.

  11. Evaluation and management of brachial plexus birth palsy.

    PubMed

    Abzug, Joshua M; Kozin, Scott H

    2014-04-01

    Brachial plexus birth palsy can result in permanent lifelong deficits and unfortunately continues to be relatively common despite advancements in obstetric care. The diagnosis can be made shortly after birth by physical examination, noting a lack of movement in the affected upper extremity. Treatment begins with passive range-of-motion exercises to maintain flexibility and tactile stimulation to provide sensory reeducation. Primary surgery consists of microsurgical nerve surgery, whereas secondary surgery consists of alternative microsurgical procedures, tendon transfers, or osteotomies, all of which improve outcomes in the short term. However, the long-term outcomes of current treatment recommendations remain unknown. PMID:24684916

  12. Nerve transfer helps repair brachial plexus injury by increasing cerebral cortical plasticity

    PubMed Central

    Sun, Guixin; Wu, Zuopei; Wang, Xinhong; Tan, Xiaoxiao; Gu, Yudong

    2014-01-01

    In the treatment of brachial plexus injury, nerves that are functionally less important are transferred onto the distal ends of damaged crucial nerves to help recover neuromuscular function in the target region. For example, intercostal nerves are transferred onto axillary nerves, and accessory nerves are transferred onto suprascapular nerves, the phrenic nerve is transferred onto the musculocutaneous nerves, and the contralateral C7 nerve is transferred onto the median or radial nerves. Nerve transfer has become a major method for reconstructing the brachial plexus after avulsion injury. Many experiments have shown that nerve transfers for treatment of brachial plexus injury can help reconstruct cerebral cortical function and increase cortical plasticity. In this review article, we summarize the recent progress in the use of diverse nerve transfer methods for the repair of brachial plexus injury, and we discuss the impact of nerve transfer on cerebral cortical plasticity after brachial plexus injury. PMID:25657729

  13. 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.

  14. 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

  15. 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.

  16. 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, oral supplementation with antioxidants appears to be an effective approach for the radioprotection of hematopoietic cells against the cell killing effects of radiation, and for improving survival in irradiated animals. Preliminary data suggest similar antioxidant protective effects for animals exposed to potentially lethal doses of proton radiation. Studies were also performed to determine whether dietary antioxidants could affect the incidence rates of malignancies in CBA mice exposed to 300 cGy proton (1 GeV/n) radiation or 50 cGy iron ion (1 GeV/n) radiation [9]. Two antioxidant formulations were utilized in these studies; an AOX formulation containing the mixture of antioxidant agents developed from our previous studies and an antioxidant dietary formulation containing the soybean-derived protease inhibitor known as the Bowman-Birk inhibitor (BBI). BBI was evaluated in the form of BBI Concentrate (BBIC), which is the form of BBI utilized in human trials. BBIC has been utilized in human trials since 1992, as described [10]. The major finding in the long-term animal studies was that there was a reduced risk of malignant lymphoma in mice exposed to space radiations and maintained on diets containing the antioxidant formulations. In addition, the two different dietary countermeasures also reduced the yields of a variety of different rare tumor types, arising from both epithelial and connective tissue cells, observed in the animals exposed to space radiation. REFERENCES [1] Guan J. et al (2004) Radiation Research 162, 572-579. [2] Wan X.S. et al (2005) Radiation Research 163, 364-368. [3] Wan X.S. et al (2005) Radiation Research 163, 232-240. [4] Guan J. et al (2006) Radiation Research 165, 373-378. [5] Wan X.S. et al (2006) International Journal of Radiation Oncology, Biology, Physics 64, 1475-1481. [6] Kennedy A.R. et al (2006) Radiation Research 166, 327-332. [7] Kennedy A.R. et al (2007) Radiation & Environmental Biophysics 46(2), 201-3. [8]Wambi, C., Sanzari, J., Wan, X.S., Nuth, M., Davis, J., Ko, Y.-H., Sayers, C.M., Baran, M., Ware, J.H. and Kennedy, A.R. Dietary antioxidants protect hematopoietic cells and improve animal survival following total body irradiation. Radiation Res. (in press) [9] Kennedy, A.R., Davis, J.G., Carlton, W. and Ware, J.H. Effects of dietary antioxidant supplementation on the development of malignancies and other neoplastic lesions in mice exposed to proton or iron ion radiation. Radiation Res. (submitted) [10] Kennedy, A.R. The Status of Human Trials Utilizing Bowman-Birk Inhibitor Concentrate from Soybeans. In: Soy in Health and Disease Prevention, edited by Michihiro Sugano, CRC Press Press LLC, Boca Raton, Florida, Chapter 12, pp. 207-223, 2005. ACKNOWLEDGEMENTS; This work was supported by the National Space Biomedical Research Institute through NASA NCC 9-58.

  17. Injury mechanisms in supraclavicular stretch injuries of the brachial plexus.

    PubMed

    Soldado, Francisco; Ghizoni, Marcos F; Bertelli, Jayme

    2016-02-01

    The aim of this study was to describe the mechanisms involved in stretch injuries of the brachial plexus. One hundred and fifty consecutive patients with supraclavicular brachial plexus injuries (BPI) were asked about the mechanism of injury during the actual injury event, particularly about the type of trauma to their shoulder, shoulder girdle and head. Fifty-seven of the patients provided enough information about their accident to allow for analysis of the shoulder trauma. The injury mechanism for all patients having upper root or total palsy (n=46) was described as a direct vertical impact to the shoulder. In 44 of these patients, the trauma followed a motorcycle accident and, in most of them, the patient hit a fixed vertical structure before falling to the ground. The injury mechanism for the lower root palsy cases (n=11) was variable. The most frequent mechanism was forceful anterior shoulder compression by a car seat belt. We found that injury mechanisms differed significantly from the ones commonly discussed in published studies. PMID:27117025

  18. Traumatic Pseudoaneurysm of Axillary Artery Combined with Brachial Plexus Injury

    PubMed Central

    Chen, Lin; Peng, Feng; Wang, Tao; Chen, Desong; Yang, Jianyun

    2014-01-01

    Traumatic pseudoaneurysm of the axillary artery combined with brachial plexus injury is extremely rare. The factors that influence the symptoms and functional recovery related to this condition are unclear. Nine patients who had sustained this trauma were surgically treated at our unit between June 1999 and November 2010. The cause of trauma, symptoms, signs and examinations of neurological and vascular deficits, and the surgical findings of the involved nerves and vessels were recorded in detail. The functional recovery of vessels and nerves, as well as the extent of pain, were evaluated, respectively. The average length of patient follow-up was 4.5 years (range, 24 months to 11.3 years). After vessel repair, whether by endovascular or operative treatment, the distending, constant, and pulsating pain was relieved in all patients. Furthermore, examination of the radial artery pulse on the repaired side appeared normal at last follow-up. All patients showed satisfactory sensory recovery, with motor recovery rated as good in five patients and fair in four patients. The symptom characteristics varied with the location of the damage to the axillary artery. Ultrasound examination and computed tomography angiography are useful to evaluate vascular injury and provide valuable information for operative planning. Surgical exploration is an effective therapy with results related to the nerve injury condition of the brachial plexus. PMID:25412426

  19. Hyperbaric Oxygen Therapy for Radiation-Induced Cystitis and Proctitis

    SciTech Connect

    Oliai, Caspian; Fisher, Brandon; Jani, Ashish; Wong, Michael; Poli, Jaganmohan; Brady, Luther W.; Komarnicky, Lydia T.

    2012-11-01

    Purpose: To provide a retrospective analysis of the efficacy of hyperbaric oxygen therapy (HBOT) for treating hemorrhagic cystitis (HC) and proctitis secondary to pelvic- and prostate-only radiotherapy. Methods and Materials: Nineteen patients were treated with HBOT for radiation-induced HC and proctitis. The median age at treatment was 66 years (range, 15-84 years). The range of external-beam radiation delivered was 50.0-75.6 Gy. Bleeding must have been refractory to other therapies. Patients received 100% oxygen at 2.0 atmospheres absolute pressure for 90-120 min per treatment in a monoplace chamber. Symptoms were retrospectively scored according to the Late Effects of Normal Tissues-Subjective, Objective, Management, Analytic (LENT-SOMA) scale to evaluate short-term efficacy. Recurrence of hematuria/hematochezia was used to assess long-term efficacy. Results: Four of the 19 patients were lost to follow-up. Fifteen patients were evaluated and received a mean of 29.8 dives: 11 developed HC and 4 proctitis. All patients experienced a reduction in their LENT-SOMA score. After completion of HBOT, the mean LENT-SOMA score was reduced from 0.78 to 0.20 in patients with HC and from 0.66 to 0.26 in patients with proctitis. Median follow-up was 39 months (range, 7-70 months). No cases of hematuria were refractory to HBOT. Complete resolution of hematuria was seen in 81% (n = 9) and partial response in 18% (n = 2). Recurrence of hematuria occurred in 36% (n = 4) after a median of 10 months. Complete resolution of hematochezia was seen in 50% (n = 2), partial response in 25% (n = 1), and refractory bleeding in 25% (n = 1). Conclusions: Hyperbaric oxygen therapy is appropriate for radiation-induced HC once less time-consuming therapies have failed to resolve the bleeding. In these conditions, HBOT is efficacious in the short and long term, with minimal side effects.

  20. Environmental applications of radiation-induced defects in clay minerals

    NASA Astrophysics Data System (ADS)

    Allard, T.

    2011-12-01

    Radiation effects on clay minerals have been studied over the last 35 years, providing a wealth of information on environmental and geological processes. They have been applied to the reconstruction of past radioelement migrations in the geosphere, the dating of clay minerals from soils or the evolution of the physico-chemical properties under irradiation. All known radiation-induced point defects in clay minerals are detected using Electron Paramagnetic Resonance Spectroscopy. They mostly consist in electron holes located on oxygen atoms of the structure, and can be differentiated through their nature and their thermal stability. For instance, several are associated to a π orbital on a Si-O bond. One defect, namely the A-center, is stable over geological periods at ambiant temperature. These point defects are produced mainly by ionizing radiations. By contrast to point defects, it was shown that electron or heavy ion irradiation easily produces amorphization in smectites. Two main applications of radiation-induced defects in clay minerals are derived : (i) the use of defects as tracers of past radioactivity. In geosystems where the age of the clay can be constrained, migrations of radioelements can be reconstructed in natural analogues of the far field of high level nuclear waste repositories. When the dose rate may be assumed constant over time, the paleodose is used to date clay populations, an approach applied to laterites of the Amazon basin. (ii) The influence of radiation on clay mineral properties that remains poorly documented, although it is an important issue in various domains such as the safety assessment of the high level nuclear waste repositories. In case of a leakage of transuranic elements from the radioactive wasteform, alpha recoil nuclei would amorphize smectite after a period much lower than the disposal lifetime. By contrast, amorphisation from ionizing radiation is unlikely over 1 million years. Furthermore, it was shown that amorphization greatly enhances the dissolution kinetics of smectite, a result that must be taken into account in the safety assessment of engineered barriers.

  1. Radiation-induced defects in clay minerals: A review

    NASA Astrophysics Data System (ADS)

    Allard, Th.; Balan, E.; Calas, G.; Fourdrin, C.; Morichon, E.; Sorieul, S.

    2012-04-01

    Extensive information has been collected on radiation effects on clay minerals over the last 35 years, providing a wealth of information on environmental and geological processes. The fields of applications include the reconstruction of past radioelement migrations, the dating of clay minerals or the evolution of the physico-chemical properties under irradiation. The investigation of several clay minerals, namely kaolinite, dickite, montmorillonite, illite and sudoite, by Electron Paramagnetic Resonance Spectroscopy has shown the presence of defects produced by natural or artificial radiations. These defects consist mostly of electron holes located on oxygen atoms of the structure. The various radiation-induced defects are differentiated through their nature and their thermal stability. Most of them are associated with a π orbital on a Si-O bond. The most abundant defect in clay minerals is oriented perpendicular to the silicate layer. Thermal annealing indicates this defect in kaolinite (A-center) to be stable over geological periods at ambient temperature. Besides, electron or heavy ion irradiation easily leads to an amorphization in smectites, depending on the type of interlayer cation. The amorphization dose exhibits a bell-shaped variation as a function of temperature, with a decreasing part that indicates the influence of thermal dehydroxylation. Two main applications of the knowledge of radiation-induced defects in clay minerals are derived: (i) The use of defects as tracers of past radioactivity. In geological systems where the age of the clay can be constrained, ancient migrations of radioelements can be reconstructed in natural analogues of high level nuclear waste repositories. When the dose rate may be assumed constant over time, the paleodose is used to date clay populations, an approach applied to fault gouges or laterites of the Amazon basin. (ii) The influence of irradiation over physico-chemical properties of clay minerals. An environmental application concerns the performance assessment of the engineered barrier of nuclear waste disposals. In case of a leakage of transuranic elements from the radioactive waste form, alpha recoil nuclei can amorphize smectite after periods of the order of 1000 years according to a worst case scenario, whereas amorphization from ionizing radiation is unlikely. As amorphization greatly enhances the dissolution kinetics of smectite, the sensitivity of the smectites must be taken into account in the prediction of the long term behavior of engineered barriers.

  2. Radiation-Induced Alterations in Mitochondria of the Rat Heart

    PubMed Central

    Sridharan, Vijayalakshmi; Aykin-Burns, Nukhet; Tripathi, Preeti; Krager, Kimberly J.; Sharma, Sunil K.; Moros, Eduardo G.; Corry, Peter M.; Nowak, Grazyna; Hauer-Jensen, Martin; Boerma, Marjan

    2014-01-01

    Radiation therapy for the treatment of thoracic cancers may be associated with radiation-induced heart disease (RIHD), especially in long-term cancer survivors. Mechanisms by which radiation causes heart disease are largely unknown. To identify potential long-term contributions of mitochondria in the development of radiation-induced heart disease, we examined the time course of effects of irradiation on cardiac mitochondria. In this study, Sprague-Dawley male rats received image-guided local X irradiation of the heart with a single dose ranging from 3–21 Gy. Two weeks after irradiation, left ventricular mitochondria were isolated to assess the dose-dependency of the mitochondrial permeability transition pore (mPTP) opening in a mitochondrial swelling assay. At time points from 6 h to 9 months after a cardiac dose of 21 Gy, the following analyses were performed: left ventricular Bax and Bcl-2 protein levels; apoptosis; mitochondrial inner membrane potential and mPTP opening; mitochondrial mass and expression of mitophagy mediators Parkin and PTEN induced putative kinase-1 (PINK-1); mitochondrial respiration and protein levels of succinate dehydrogenase A (SDHA); and the 70 kDa subunit of complex II. Local heart irradiation caused a prolonged increase in Bax/Bcl-2 ratio and induced apoptosis between 6 h and 2 weeks. The mitochondrial membrane potential was reduced until 2 weeks, and the calcium-induced mPTP opening was increased from 6 h up to 9 months. An increased mitochondrial mass together with unaltered levels of Parkin suggested that mitophagy did not occur. Lastly, we detected a significant decrease in succinate-driven state 2 respiration in isolated mitochondria from 2 weeks up to 9 months after irradiation, coinciding with reduced mitochondrial levels of succinate dehydrogenase A. Our results suggest that local heart irradiation induces long-term changes in cardiac mitochondrial membrane functions, levels of SDH and state 2 respiration. At any time after exposure to radiation, cardiac mitochondria are more prone to mPTP opening. Future studies will determine whether this makes the heart more susceptible to secondary stressors such as calcium overload or ischemia/reperfusion. PMID:24568130

  3. Complications of Lower-Extremity Outpatient Arteriography via Low Brachial Artery

    SciTech Connect

    Chatziioannou, A.; Ladopoulos, C.; Mourikis, D.; Katsenis, K.; Spanomihos, G.; Vlachos, L.

    2004-01-15

    We retrospectively evaluated low brachial artery puncture for arteriography and its complications as an alternative approach route for bilateral lower extremity run-off. Using the Seldinger technique and catheterization with a sheathless 4-F multiple side-hole pigtail catheter, we performed 2250 low brachial artery punctures in outpatients.The right brachial artery (RBA) was successfully punctured in 2039 patients; the left brachial artery (LBA) in 200. The transfemoral approach was used in 11 patients when catheterizing either of brachial arteries failed. Ten major or moderate complications (2 pseudoaneurysms, 2 thrombosis, 1 dissection and 5 hematomas) were encountered. Surgical intervention was necessary in three cases. There were no transient ischemic attacks. Twenty-one patients suffered temporary loss of radial pulse which returned spontaneously in less than 1 hour. One patient demonstrated prolonged loss of pulse which required heparin. Low brachial artery puncture and catheterization at the antecubital fossa is a very safe and cost-effective alternative to the femoral artery approach for lower extremity intra-arterial arteriography in the hands of experienced operators. The success rate in catheterizing one of the brachial arteries was 99.52% with a low significant complications rate of 0.44%. The transbrachial approach should be used as a standard method for lower extremity IA - DSA in an outpatient setting.

  4. Differential associations of central and brachial blood pressure with carotid atherosclerosis and microvascular complications in patients with type 2 diabetes

    PubMed Central

    2014-01-01

    Background We examined the relationship between central blood pressure (BP), brachial BP with carotid atherosclerosis and microvascular complications in type 2 diabetes mellitus (T2DM). Methods We recruited 201 patients who were evaluated for central BP, brachial BP, carotid ultrasonography, brachial-ankle pulse wave velocity (baPWV), ankle-brachial index (ABI) and microvascular complications. Central BP were calculated using a radial automated tonometric system. Results Agreement between central BP and brachial BP was very strong (concordance correlation coefficient between central and brachial SBP = 0.889, between central and brachial PP = 0.816). Central pulse pressure (PP) was correlated with mean carotid intima-media thickness (CIMT), baPWV and ABI, whereas brachial PP was borderline significantly correlated with CIMT. The prevalence of nephropathy(DN) and retinopathy(DR) according to the brachial PP tertiles increased, the prevalences of microvascular complications were not different across central PP tertiles. In multivariate analysis, the relative risks (RRs) for the presence of DR were 1.2 and 4.6 for the brachial PP tertiles 2 and 3 when compared with the first tertile. Also, the RRs for the presence of DN were 1.02 and 3 for the brachial PP tertiles 2 and 3 when compared with the first tertile. Conclusions Agreement of central BP and brachial BP was very strong. Nonetheless, this study showed that higher brachial PP levels are associated with increased probability for the presence of microvascular complications such as DR/DN. However, there are no associations with central SBP and central PP with microvascular complications. Central BP levels than brachial BP are correlated with surrogate marker of macrovascular complications. PMID:24555866

  5. Significant Correlation between Brachial Pulse Pressure Index and Renal Resistive Index

    PubMed Central

    Lee, Meng-Kuang; Hsu, Po-Chao; Chu, Chun-Yuan; Lee, Wen-Hsien; Chen, Szu-Chia; Chen, Huang-Chi; Su, Ho-Ming; Lin, Tsung-Hsien; Voon, Wen-Chol; Lai, Wen-Ter; Sheu, Sheng-Hsiung

    2015-01-01

    Background The renal resistive index (RI) is calculated as (peak systolic velocity - minimum diastolic velocity)/peak systolic velocity, and has been significantly associated with renal function. Pulse pressure index (PPI) is derived from a formula similar to renal RI, i.e. (systolic blood pressure - diastolic blood pressure)/systolic blood pressure. The purpose of this study was to investigate whether brachial PPI had a significant correlation with renal RI and could be used in identifying patients with impaired renal function. Methods We consecutively enrolled 255 patients referred for echocardiographic examination. The renal RI was measured from Doppler ultrasonography and blood pressure was measured from an ABI-form device. Results Patients with brachial PPI ≥ 0.428 (mean value of brachial PPI) had a lower estimated glomerular filtration rate (eGFR) than those with brachial PPI < 0.428 (p < 0.001). After the multivariate analysis was completed, brachial PPI had a significant correlation with renal RI (unstandardized coefficient β = 0.53, p < 0.001). The areas under the curve for brachial PPI and renal RI in prediction of eGFR < 45 mL/min/1.73 m2 were 0.682 and 0.893 (both p < 0.001), respectively. Conclusions Brachial PPI was significantly correlated with renal RI. Patients with higher brachial PPI had a more reduced renal function. Hence, brachial PPI may be able to quickly reflect the intrarenal vascular hemodynamics, and may serve as an important tool for screening and follow-up for patients with abnormal renovascular resistance. PMID:27122855

  6. Concomitant Traumatic Spinal Cord and Brachial Plexus Injuries in Adult Patients

    PubMed Central

    Rhee, Peter C.; Pirola, Elena; Hébert-Blouin, Marie-Noëlle; Kircher, Michelle F.; Spinner, Robert J.; Bishop, Allen T.; Shin, Alexander Y.

    2011-01-01

    Background: Combined injuries to the spinal cord and brachial plexus present challenges in the detection of both injuries as well as to subsequent treatment. The purpose of this study is to describe the epidemiology and clinical factors of concomitant spinal cord injuries in patients with a known brachial plexus injury. Methods: A retrospective review was performed on all patients who were evaluated for a brachial plexus injury in a tertiary, multidisciplinary brachial plexus clinic from January 2000 to December 2008. Patients with clinical and/or imaging findings for a coexistent spinal cord injury were identified and underwent further analysis. Results: A total of 255 adult patients were evaluated for a traumatic traction injury to the brachial plexus. We identified thirty-one patients with a combined brachial plexus and spinal cord injury, for a prevalence of 12.2%. A preganglionic brachial plexus injury had been sustained in all cases. The combined injury group had a statistically greater likelihood of having a supraclavicular vascular injury (odds ratio [OR] = 22.5; 95% confidence interval [CI] = 1.9, 271.9) and a cervical spine fracture (OR = 3.44; 95% CI = 1.6, 7.5). These patients were also more likely to exhibit a Horner sign (OR = 3.2; 95% CI = 1.5, 7.2) and phrenic nerve dysfunction (OR = 2.5; 95% CI = 1.0, 5.8) compared with the group with only a brachial plexus injury. Conclusion: Heightened awareness for a combined spinal cord and brachial plexus injury and the presence of various associated clinical and imaging findings may aid in the early recognition of these relatively uncommon injuries. Level of Evidence: Therapeutic Level IV. See Instructions to Authors for a complete description of levels of evidence. PMID:22258773

  7. 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.

  8. Chromatin Structure and Radiation-Induced Intrachromosome Exchange

    NASA Technical Reports Server (NTRS)

    Mangala; Zhang, Ye; Hada, Megumi; Cucinotta, Francis A.; Wu, Honglu

    2011-01-01

    We have recently investigated the location of breaks involved in intrachromosomal type exchange events, using the multicolor banding in situ hybridization (mBAND) technique for human chromosome 3. In human epithelial cells exposed to both low- and high-LET radiations in vitro, intrachromosome exchanges were found to occur preferentially between a break in the 3p21 and one in the 3q11. Exchanges were also observed between a break in 3p21 and one in 3q26, but few exchanges were observed between breaks in 3q11 and 3q26, even though the two regions were on the same arm of the chromosome. To explore the relationships between intrachromosome exchanges and chromatin structure, we used probes that hybridize the three regions of 3p21, 3q11 and 3q26, and measured the distance between two of the three regions in interphase cells. We further analyzed fragile sites on the chromosome that have been identified in various types of cancers. Our results demonstrated that the distribution of breaks involved in radiation-induced intrachromosome aberrations depends upon both the location of fragile sites and the folding of chromatins

  9. Adaptive radiation-induced epigenetic alterations mitigated by antioxidants

    PubMed Central

    Bernal, Autumn J.; Dolinoy, Dana C.; Huang, Dale; Skaar, David A.; Weinhouse, Caren; Jirtle, Randy L.

    2013-01-01

    Humans are exposed to low-dose ionizing radiation (LDIR) from a number of environmental and medical sources. In addition to inducing genetic mutations, there is concern that LDIR may also alter the epigenome. Such heritable effects early in life can either be positively adaptive or result in the enhanced formation of diseases, including cancer, diabetes, and obesity. Herein, we show that LDIR significantly increased DNA methylation at the viable yellow agouti (Avy) locus in a sex-specific manner (P=0.004). Average DNA methylation was significantly increased in male offspring exposed to doses between 0.7 and 7.6 cGy, with maximum effects at 1.4 and 3.0 cGy (P<0.01). Offspring coat color was concomitantly shifted toward pseudoagouti (P<0.01). Maternal dietary antioxidant supplementation mitigated both the DNA methylation changes and coat color shift in the irradiated offspring. Thus, LDIR exposure during gestation elicits epigenetic alterations that lead to positive adaptive phenotypic changes that are negated with antioxidants, indicating they are mediated in part by oxidative stress. These findings provide evidence that in the isogenic Avy mouse model, epigenetic alterations resulting from LDIR play a role in radiation hormesis, bringing into question the assumption that every dose of radiation is harmful.—Bernal, A. J., Dolinoy, D. C., Huang, D., Skaar, D. A., Weinhouse, C., Jirtle, R. J. Adaptive radiation-induced epigenetic alterations mitigated by antioxidants. PMID:23118028

  10. 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.

  11. 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.

  12. 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

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

    PubMed Central

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

    2013-01-01

    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.

  14. Ionizing Radiation-Induced Cataract in Interventional Cardiology Staff

    PubMed Central

    Bitarafan Rajabi, Ahmad; Noohi, Feridoun; Hashemi, Hassan; Haghjoo, Majid; Miraftab, Mohammad; Yaghoobi, Nahid; Rastgou, Fereydon; Malek, Hadi; Faghihi, Hoshang; Firouzabadi, Hassan; Asgari, Soheila; Rezvan, Farhad; Khosravi, Hamidreza; Soroush, Sara; Khabazkhoob, Mehdi

    2015-01-01

    Background: The use of ionizing radiation has led to advances in medical diagnosis and treatment. Objectives: The purpose of this study was to determine the risk of radiation cataractogenesis in the interventionists and staff performing various procedures in different interventional laboratories. Patients and Methods: This cohort study included 81 interventional cardiology staff. According to the working site, they were classified into 5 groups. The control group comprised 14 professional nurses who did not work in the interventional sites. Participants were assigned for lens assessment by two independent trained ophthalmologists blinded to the study. Results: The electrophysiology laboratory staff received higher doses of ionizing radiation (17.2 ± 11.9 mSv; P < 0.001). There was a significant positive correlation between the years of working experience and effective dose in the lens (P < 0.001). In general, our findings showed that the incidence of lens opacity was 79% (95% CI, 69.9-88.1) in participants with exposure (the case group) and our findings showed that the incidence of lenses opacity was 7.1% (95% CI:2.3-22.6) with the relative risk (RR) of 11.06 (P < 0.001). Conclusions: We believe that the risk of radiation-induced cataract in cardiology interventionists and staff depends on their work site. As the radiation dose increases, the prevalence of posterior eye changes increases. PMID:25789258

  15. 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. PMID:8105010

  16. 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.

  17. 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.

  18. 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.

  19. 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.

  20. 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.

  1. 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. PMID:26320421

  2. 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.

  3. Radiation-induced tumours of the head and neck.

    PubMed

    van der Laan, B F; Baris, G; Gregor, R T; Hilgers, F J; Balm, A J

    1995-04-01

    In order to study the induction of malignancy in normal tissues due to ionizing radiation, we reviewed the files of 2500 patients with a tumour of the head and neck treated at the Netherlands Cancer Institute (Antoni van Leeuwenhoek Ziekenhuis), Amsterdam, from 1977 to 1993. We then checked whether or not these patients had been previously irradiated. Patients with a thyroid carcinoma or skin cancer were excluded from the study, since it is generally known that previous irradiation is a risk factor in these tumours. Eighteen patients were found to have a malignancy within a previously irradiated area (0.70 per cent). The mean interval between radiation and diagnosis of the head and neck tumour was 36.5 years. There were five soft tissue sarcomas, nine squamous cell carcinomas and four salivary gland tumours. Fourteen patients were operated upon whereas four received palliative treatment only. The median survival of the total group was 3.5 years. Particularly, in young patients because of the better cancer therapy and prolonged survival one must be aware of the increased risk of radiation-induced tumours. PMID:7782698

  4. Radiation-Induced Bystander Response: Mechanism and Clinical Implications

    PubMed Central

    Suzuki, Keiji; Yamashita, Shunichi

    2014-01-01

    Significance: Absorption of energy from ionizing radiation (IR) to the genetic material in the cell gives rise to damage to DNA in a dose-dependent manner. There are two types of DNA damage; by a high dose (causing acute or deterministic effects) and by a low dose (related to chronic or stochastic effects), both of which induce different health effects. Among radiation effects, acute cutaneous radiation syndrome results from cell killing as a consequence of high-dose exposure. Recent advances: Recent advances in radiation biology and oncology have demonstrated that bystander effects, which are emerged in cells that have never been exposed, but neighboring irradiated cells, are also involved in radiation effects. Bystander effects are now recognized as an indispensable component of tissue response related to deleterious effects of IR. Critical issues: Evidence has indicated that nonapoptotic premature senescence is commonly observed in various tissues and organs. Senesced cells were found to secrete various proteins, including cytokines, chemokines, and growth factors, most of which are equivalent to those identified as bystander factors. Secreted factors could trigger cell proliferation, angiogenesis, cell migration, inflammatory response, etc., which provide a tissue microenvironment assisting tissue repair and remodeling. Future directions: Understandings of the mechanisms and physiological relevance of radiation-induced bystander effects are quite essential for the beneficial control of wound healing and care. Further studies should extend our knowledge of the mechanisms of bystander effects and mode of cell death in response to IR. PMID:24761341

  5. 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.

  6. 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.

  7. 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.

  8. 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

    2016-01-01

    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

  9. 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

  10. Countermeasures for space radiation induced adverse biologic effects

    NASA Astrophysics Data System (ADS)

    Kennedy, A. R.; Wan, X. S.

    2011-11-01

    Radiation exposure in space is expected to increase the risk of cancer and other adverse biological effects in astronauts. The types of space radiation of particular concern for astronaut health are protons and heavy ions known as high atomic number and high energy (HZE) particles. Recent studies have indicated that carcinogenesis induced by protons and HZE particles may be modifiable. We have been evaluating the effects of proton and HZE particle radiation in cultured human cells and animals for nearly a decade. Our results indicate that exposure to proton and HZE particle radiation increases oxidative stress, cytotoxicity, cataract development and malignant transformation in in vivo and/or in vitro experimental systems. We have also shown that these adverse biological effects can be prevented, at least partially, by treatment with antioxidants and some dietary supplements that are readily available and have favorable safety profiles. Some of the antioxidants and dietary supplements are effective in preventing radiation induced malignant transformation in vitro even when applied several days after the radiation exposure. Our recent progress is reviewed and discussed in the context of the relevant literature.

  11. 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. PMID:24956797

  12. Radiation induced oxidation of liquid alkanes as a polymer model

    NASA Astrophysics Data System (ADS)

    Soebianto, Yanti S.; Katsumura, Yosuke; Ishigure, Kenkichi; Kubo, Junichi; Hamakawa, Satoshi; Kudoh, Hisaaki; Seguchi, Tadao

    1996-10-01

    Radiation induced oxidation of liquid n-hexadecane ( n-C 16H 34) and squalene (C 30H 62) as a polymer model has been investigated by the measurements of the gas evolution and O 2 uptake, and analyses of the oxidation products. Low O 2 uptake [G(-O 2 ≈ 6.0] in liquid alkanes, indicates in solid oxidation reaction does not exhibit chain kinetics, which is a big contrast to the process observed in solid, G(-O 2) ≫ 10. H 2 is the main gas product. More than 90% of the consumed O 2 are converted into the oxidation products in liquid phase, mainly carboxylic acids, which is also a big contrast to the results of the radiolysis of liquid cyclohexane in the presence of O 2 and thermal oxidation of hexadecene at elevated temperatures, where ketones and alcohols are major products at the initial stage. In the presence of aromatic additives, energy and charge transfer to the additives taking place despite the presence of O 2 reduce the H 2 evolution and the acid formation in parallel. Although hydroaromatic compounds act as an energy and charge scavenger, the are selectively oxidized through the donation of hydrogen in cyclic alkyl part attached to the phenyl ring, leading to large O 2 uptake and corresponding ketone formation. From the comparison of the G-values of the O 2 uptake, it was found that the oxidation reactions of liquid alkanes reflect well the oxidation of amorphous part in polymers.

  13. 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.

  14. An ESR study of radiation induced radicals in glucose polymers

    NASA Astrophysics Data System (ADS)

    Kameya, Hiromi; Ukai, Mitsuko; Shimoyama, Yuhei

    2013-03-01

    Using electron spin resonance (ESR) spectroscopy with both experimental and theoretical approaches, we revealed the γ-radiation induced radicals in two glucose polymers, cellulose and starch. Before irradiation, ESR signals are silent in both the glucose polymers. After irradiation, a singlet signal at g=2.0 appeared in both the glucose polymers. The twin peaks were invisible in the starch sample. We identified the twin peaks to be a part of triplet signal and analyzed the molecular structure of the cellulose radical. Through theoretical simulations, we revealed, for the first time, that the triplet signal was due to hyperfine interactions of unpaired electron with two protons in the cellulose radical. The third peak within the triplet is overlapped by the free radical at g=2.0. We further found that the cellulose radical does not remain at the rigid limit or the static state, but undergoes axial rotations around C-C and C-H bonds. We concluded that the triplet ESR signal reflects the cellulose radical.

  15. 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.

  16. Comparison of brachial dilatory responses to hypercapnia and reactive hyperemia.

    PubMed

    Geijer, Justin R; Hultgren, Neil E; Evanoff, Nicholas G; Kelly, Aaron S; Chernin, Michael A; Stoltman, Matthew G; Dengel, Donald R

    2016-03-01

    Flow-mediated dilation (FMD) relies on reactive hyperemia to stimulate the endothelium to release nitric oxide, causing smooth muscle relaxation. Hypercapnia also produces vasodilation, which is thought to be nitric oxide-independent. The purpose of this study was to compare and contrast the effects of hypercapnia and reactive hyperemia as stimuli for brachial artery dilation. On separate days, twenty-five participants underwent vasodilation studies via reactive hyperemia or hypercapnia (i.e. 10 mmHg increase in end-tidal carbon dioxide [PetCO2)]). During both studies changes in brachial artery diameter were recorded using continuous ultrasound imaging. Heart rate (HR) was measured throughout both tests. Resting HR (63  ±  11 versus 68  ±  14 beats min(-1), p  =  0.0027) and baseline brachial artery diameter measurements (4.57  ±  1.51 versus 5.28  ±  1.86 mm, p  =  0.022) were significantly different between reactive hyperemia and hypercapnia, respectively. HR at peak dilation (65  ±  11 versus 76  ±  14 beats min(-1), p  <  0.0001), peak vessel dilation (8.68  ±  4.50 versus 5.28  ±  1.86%, p  =  0.002), and time to peak dilation (90.8  ±  120.1 versus 658.3  ±  226.6 s, p  <  0.0001) were also significantly different between reactive hyperemia and hypercapnia. The dynamics by which reactive hyperemia and hypercapnia stimulate vasodilation appear to differ. Hypercapnia produces a smaller and slower vasodilatory effect than reactive hyperemia. Further research is necessary to better understand the mechanisms of vasodilation under hypercapnic conditions. PMID:26862786

  17. Brachial-Ankle Pulse Wave Velocity: Myths, Misconceptions, and Realities

    PubMed Central

    Sugawara, Jun; Tanaka, Hirofumi

    2015-01-01

    A variety of techniques to evaluate central arterial stiffness have been developed and introduced. None of these techniques, however, have been implemented widely in regular clinical settings, except for brachial-ankle pulse wave velocity (baPWV). The most prominent procedural advantage of baPWV is its ease of use, since it only requires the wrapping of blood pressure cuffs on the 4 extremities. There is mounting evidence indicating the ability of baPWV to predict the risk of future cardiovascular events and total mortality. Additionally, the guidelines for the management of hypertension in Japan recommended the measurement of baPWV be included in the assessment of subclinical target organ damage. However, baPWV has not been fully accepted worldwide due to perceived theoretical and methodological issues. In this review, we address the most frequently mentioned questions and concerns regarding baPWV to shed some light on this simple and easy arterial stiffness measurement. PMID:26587459

  18. Brachial-Ankle Pulse Wave Velocity: Myths, Misconceptions, and Realities.

    PubMed

    Sugawara, Jun; Tanaka, Hirofumi

    2015-09-01

    A variety of techniques to evaluate central arterial stiffness have been developed and introduced. None of these techniques, however, have been implemented widely in regular clinical settings, except for brachial-ankle pulse wave velocity (baPWV). The most prominent procedural advantage of baPWV is its ease of use, since it only requires the wrapping of blood pressure cuffs on the 4 extremities. There is mounting evidence indicating the ability of baPWV to predict the risk of future cardiovascular events and total mortality. Additionally, the guidelines for the management of hypertension in Japan recommended the measurement of baPWV be included in the assessment of subclinical target organ damage. However, baPWV has not been fully accepted worldwide due to perceived theoretical and methodological issues. In this review, we address the most frequently mentioned questions and concerns regarding baPWV to shed some light on this simple and easy arterial stiffness measurement. PMID:26587459

  19. Ultrasonography of the brachial plexus, normal appearance and practical applications.

    PubMed

    Lapegue, F; Faruch-Bilfeld, M; Demondion, X; Apredoaei, C; Bayol, M A; Artico, H; Chiavassa-Gandois, H; Railhac, J-J; Sans, N

    2014-03-01

    Ultrasound examination of the brachial plexus, although at first sight difficult, is perfectly feasible with fairly rapid practical and theoretical training. The roots are accurately identified due to the shape (a single tubercle) of the transverse process of C7 in the paravertebral space, and the superficial position of C5 in the interscalene groove. The tlphrique technique allows the roots, trunks and cords to be followed easily into the supraclavicular fossa. In just a few years, ultrasound imaging of the plexus has become a routine anesthesia examination for guiding nerve blocks. In trained hands, it also provides information in thoracic outlet syndromes, traumatic conditions (particularly for postganglionic lesions) and tumoral diseases. Even if MRI remains the standard examination in these indications, ultrasound, with its higher definition and dynamic character, is an excellent additional method which is still under-exploited. PMID:24603038

  20. 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.

  1. 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.

  2. Role of PECAM-1 in radiation-induced liver inflammation

    PubMed Central

    Malik, Ihtzaz Ahmed; Stange, Ina; Martius, Gesa; Cameron, Silke; Rave-Fränk, Margret; Hess, Clemens Friedrich; Ellenrieder, Volker; Wolff, Hendrik Andreas

    2015-01-01

    Platelet endothelial cell adhesion molecule-1 (PECAM-1, CD31) is known to play an important role in hepatic inflammation. Therefore, we investigated the role of PECAM-1 in wild-type (WT) and knock-out (KO)-mice after single-dose liver irradiation (25 Gy). Both, at mRNA and protein level, a time-dependent decrease in hepatic PECAM-1, corresponding to an increase in intercellular cell adhesion molecule-1 (ICAM-1) (6 hrs) was detected in WT-mice after irradiation. Immunohistologically, an increased number of neutrophil granulocytes (NG) (but not of mononuclear phagocytes) was observed in the liver of WT and PECAM-1-KO mice at 6 hrs after irradiation. The number of recruited NG was higher and prolonged until 24 hrs in KO compared to WT-mice. Correspondingly, a significant induction of hepatic tumour necrosis factor (TNF)-α and CXC-chemokines (KC/CXCL1 interleukin-8/CXCL8) was detected together with an elevation of serum liver transaminases (6–24 hrs) in WT and KO-mice. Likewise, phosphorylation of signal transducer and activator of transcription-3 (STAT-3) was observed in both animal groups after irradiation. The level of all investigated proteins as well as of the liver transaminases was significantly higher in KO than WT-mice. In the cell-line U937, irradiation led to a reduction in PECAM-1 in parallel to an increased ICAM-1 expression. TNF-α-blockage by anti-TNF-α prevented this change in both proteins in cell culture. Radiation-induced stress conditions induce a transient accumulation of granulocytes within the liver by down-regulation/absence of PECAM-1. It suggests that reduction/lack in PECAM-1 may lead to greater and prolonged inflammation which can be prevented by anti-TNFα. PMID:26177067

  3. 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.

  4. Molecular responses of radiation-induced liver damage in rats

    PubMed Central

    CHENG, WEI; XIAO, LEI; AINIWAER, AIMUDULA; WANG, YUNLIAN; WU, GE; MAO, RUI; YANG, YING; BAO, YONGXING

    2015-01-01

    The aim of the present study was to investigate the molecular responses involved in radiation-induced liver damage (RILD). Sprague-Dawley rats (6-weeks-old) were irradiated once at a dose of 20 Gy to the right upper quadrant of the abdomen. The rats were then sacrificed 3 days and 1, 2, 4, 8 and 12 weeks after irradiation and rats, which were not exposed to irradiation were used as controls. Weight measurements and blood was obtained from the rats and liver tissues were collected for histological and apoptotic analysis. Immunohistochemistry, reverse transcription quantitative polymerase chain reaction (RT-qPCR) and western blot analysis were performed to measure the expression levels of mRNAs and proteins, respectively. The serum levels of alanine aminotransferase, aspartate aminotransferase and alkaline phosphatase were increased significantly in the RILD rats. Histological investigation revealed the proliferation of collagen and the formation of fibrotic tissue 12 weeks after irradiation. Apoptotic cells were observed predominantly 2 and 4 weeks after irradiation. The immunohistochemistry, RT-qPCR and western blot analysis all revealed the same pattern of changes in the expression levels of the molecules assessed. The expression levels of transforming growth factor-β1 (TGF-β1), nuclear factor (NF)-κB65, mothers against decapentaplegic homolog 3 (Smad3) and Smad7 and connective tissue growth factor were increased during the recovery period following irradiation up to 12 weeks. The expression levels of tumor necrosis factor-α, Smad7 and Smad4 were only increased during the early phase (first 4 weeks) of recovery following irradiation. In the RILD rat model, the molecular responses indicated that the TGF-β1/Smads and NF-κB65 signaling pathways are involved in the mechanism of RILD recovery. PMID:25483171

  5. Role of PECAM-1 in radiation-induced liver inflammation.

    PubMed

    Malik, Ihtzaz Ahmed; Stange, Ina; Martius, Gesa; Cameron, Silke; Rave-Fränk, Margret; Hess, Clemens Friedrich; Ellenrieder, Volker; Wolff, Hendrik Andreas

    2015-10-01

    Platelet endothelial cell adhesion molecule-1 (PECAM-1, CD31) is known to play an important role in hepatic inflammation. Therefore, we investigated the role of PECAM-1 in wild-type (WT) and knock-out (KO)-mice after single-dose liver irradiation (25 Gy). Both, at mRNA and protein level, a time-dependent decrease in hepatic PECAM-1, corresponding to an increase in intercellular cell adhesion molecule-1 (ICAM-1) (6 hrs) was detected in WT-mice after irradiation. Immunohistologically, an increased number of neutrophil granulocytes (NG) (but not of mononuclear phagocytes) was observed in the liver of WT and PECAM-1-KO mice at 6 hrs after irradiation. The number of recruited NG was higher and prolonged until 24 hrs in KO compared to WT-mice. Correspondingly, a significant induction of hepatic tumour necrosis factor (TNF)-α and CXC-chemokines (KC/CXCL1 interleukin-8/CXCL8) was detected together with an elevation of serum liver transaminases (6-24 hrs) in WT and KO-mice. Likewise, phosphorylation of signal transducer and activator of transcription-3 (STAT-3) was observed in both animal groups after irradiation. The level of all investigated proteins as well as of the liver transaminases was significantly higher in KO than WT-mice. In the cell-line U937, irradiation led to a reduction in PECAM-1 in parallel to an increased ICAM-1 expression. TNF-α-blockage by anti-TNF-α prevented this change in both proteins in cell culture. Radiation-induced stress conditions induce a transient accumulation of granulocytes within the liver by down-regulation/absence of PECAM-1. It suggests that reduction/lack in PECAM-1 may lead to greater and prolonged inflammation which can be prevented by anti-TNFα. PMID:26177067

  6. Radiation-Induced Impairment in Lung Lymphatic Vasculature

    PubMed Central

    Cui, Ye; Wilder, Julie; Rietz, Cecilia; Gigliotti, Andrew; Tang, Xiaomeng; Shi, Yuanyuan; Guilmette, Raymond; Wang, Hao; George, Gautam; de Magaldi, Eduarda Nilo; Chu, Sarah G.; Doyle-Eisele, Melanie; McDonald, Jacob D.; Rosas, Ivan O.

    2014-01-01

    Abstract Background: The lymphatic vasculature has been shown to play important roles in lung injury and repair, particularly in lung fibrosis. The effects of ionizing radiation on lung lymphatic vasculature have not been previously reported. Methods and Results: C57Bl/6 mice were immobilized in a lead shield exposing only the thoracic cavity, and were irradiated with a single dose of 14 Gy. Animals were sacrificed and lungs collected at different time points (1, 4, 8, and 16 weeks) following radiation. To identify lymphatic vessels in lung tissue sections, we used antibodies that are specific for lymphatic vessel endothelial receptor 1 (LYVE-1), a marker of lymphatic endothelial cells (LEC). To evaluate LEC cell death and oxidative damage, lung tissue sections were stained for LYVE-1 and with TUNEL staining, or 8-oxo-dG respectively. Images were imported into ImageJ v1.36b and analyzed. Compared to a non-irradiated control group, we observed a durable and progressive decrease in the density, perimeter, and area of lymphatic vessels over the study period. The decline in the density of lymphatic vessels was observed in both subpleural and interstitial lymphatics. Histopathologically discernible pulmonary fibrosis was not apparent until 16 weeks after irradiation. Furthermore, there was significantly increased LEC apoptosis and oxidative damage at one week post-irradiation that persisted at 16 weeks. Conclusions: There is impairment of lymphatic vasculature after a single dose of ionizing radiation that precedes architectural distortion and fibrosis, suggesting important roles for the lymphatic circulation in the pathogenesis of the radiation-induced lung injury. PMID:25412238

  7. 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. PMID:26246713

  8. 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.

  9. Ultrasound-guided supraclavicular brachial plexus block in pediatric patients -A report of four cases-

    PubMed Central

    Yang, Chun Woo; Kwon, Hee Uk; Roh, Jae Young; Heo, Youn Moo; Ahn, Sung-Min

    2010-01-01

    Supraclavicular brachial plexus blocks are not common in pediatric patients due to the risk of pneumothorax. Ultrasonography is an important tool for identifying nerves during regional anesthesia. Directly visualizing the target nerves and monitoring the distribution of the local anesthetic are potentially significant. In addition, ultrasound monitoring helps avoid complications, such as inadvertent intravascular injection or pneumothorax. This paper reports four cases of pediatric patients who received ultrasound-guided supraclavicular brachial plexus block for upper limb surgery. PMID:21286471

  10. Brachial Artery-Brachial Vein Fistula for Hemodialysis: One- or Two-Stage Procedure-A Review.

    PubMed

    Kotsis, T; Moulakakis, K G; Mylonas, S N; Kalogeropoulos, P; Dellis, A; Vasdekis, S

    2016-03-01

    Purpose?The purpose of the study was to investigate the patency rate of the brachial vein transposition-arteriovenous fistula [BVT-AVF] and to review the available literature regarding the comparison of the one-stage with the two-stage procedure. Methods?A multiple electronic health database search was performed, aiming to identify studies on brachial vein superficialization. Case reports and series with five or less patients were excluded from the study. End points of the study were the patency rates at 12, 24, and 36 months of follow-up. The patency of the one- or two-stage BVT-AVF procedure was investigated. Results?Overall, 380 BVT-AVFs were analyzed. The primary patency rate at 12 months ranged between 24 and 77%. Rate of early fistula malfunction or failure of maturation of the fistula resulting in loss of functionality ranged from 0 to 53%. Forearm edema, hematomas, wound infection, and early thrombosis were among the most common complications. Limited data were available for the comparison of patency rates between the one- and the two-stage procedure because of the absence of sufficient comparative studies. However, series with one-stage procedure presented a lower patency rate at 12 months compared to series with two stages. Conclusion?Patency rates after BVT-AVF, although not excellent, has encouraging results taking into account that patients undergoing these procedures do not have an accessible superficial vein network; failure of maturation and the increased rate of early postoperative complications remain a concern. The BVT-AVF is a valuable option for creating an autologous vascular access in patients lacking adequate superficial veins. PMID:26900307

  11. 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

  12. A Case of Radiation-Induced Osteosarcoma after the Treatment of Pineoblastoma

    PubMed Central

    Hong, Noah; Yoo, Heon; Shin, Sang Hoon; Gwak, Ho Shin

    2015-01-01

    Radiation therapy has an important role in postoperative treatment of neoplasms originated from central nervous system, but may induce secondary malignancies like as sarcomas, gliomas, and meningiomas. The prognosis of radiation-induced osteosarcomas is known as poor, because they has aggressive nature invasive locally and intractable to multiple treatment strategies like as surgical resection, chemotherapy, and so on. We report a case of radiation-induced osteosarcoma developed from skull after 7 years of craniospinal radiotherapy for pineoblastoma. PMID:26605276

  13. Radiation-induced changes affecting polyester based polyurethane binder

    NASA Astrophysics Data System (ADS)

    Pierpoint, Sujita Basi

    The application of thermoplastic polyurethane elastomers as binders in the high energy explosives particularly when used in weapons presents a significantly complex and challenging problem due to the impact of the aging of this polymer on the useful service life of the explosive. In this work, the effects of radiation on the aging of the polyester based polyurethane were investigated using both electron beam and gamma irradiation at various dose rates in the presence and absence of oxygen. It was found by means of GPC that, in the presence and absence of oxygen, the poly (ester urethane) primarily undergoes cross-linking, by means of a carbon-centered secondary alkyl radical. It was also concluded that the polymer partially undergoes scission of the backbone of the main chain at C-O, N-C, and C-C bonds. Substantial changes in the conditions of irradiation and in dose levels did not affect the cross-linking and scission yields. Experiments were also performed with EPR spectroscopy for the purpose of identifying the initial carbon-centered free radicals and for studying the decay mechanisms of these radicals. It was found that the carbon-centered radical which is produced via C-C scission (primary alkyl radical) is rapidly converted to a long-lived allylic species at higher temperatures; more than 80% radicals are converted to allyl species in 2.5 hours. In the presence of oxygen, the allyl radical undergoes a fast reaction to produce a peroxyl radical; this radical decays with a 1.7 hour half-life by pseudo first-order kinetics to negligible levels in 13 hours. FTIR measurements were conducted to identify the radiation-induced changes to the functional groups in the polyester polyurethane. These measurements show an increase in carbonyl, amine and carboxylic groups as a result of reaction of H atoms with R-C-O·, ·NH-R and R-COO·. The FTIR results also demonstrate the production of the unsaturation resulting from hydrogen atom transfer during intrachain conversion of the primary alkyl radical to the allyl species, prompt trans-vinylene production in tetramethylene units, and hydrogen atom abstraction by alkyl radicals on neighboring chains. The production of unsaturation is substantiated by the EPR studies. Finally, a free radical mechanism is proposed for the production of cross-linking in polyester polyurethane.

  14. Radiation Induced Segregation in High Chromium Ferritic/Martensitic Steels

    NASA Astrophysics Data System (ADS)

    Field, Kevin G.

    High Cr ferritic/martensitic (F/M) steels including nano-featured oxide dispersion strengthened steels (NF-ODS) are a candidate material class for advanced fission and fusion nuclear reactor designs. F/M steels have excellent high temperature strength, low swelling rates and the recent developments in NF-ODS steels has improved their high temperature creep performance. A concern for F/M steels is their radiation induced segregation (RIS) response while in-service. RIS occurs when atomic fluxes preferentially couple to point defect fluxes to defect sinks such as grain boundaries (GBs). For F/M steels no conclusive trends or dependencies on the RIS response have been drawn. Interfaces, including grain boundaries and precipitate-matrix interfaces can alter the RIS response. The grain boundary structure could change the point defect interaction at the GB. Changes in the point defect kinetics at a grain boundary could therefore alter the RIS response at the boundary. Furthermore, oxide nanoclusters in NF-ODS steel act as sinks for point defects under irradiation. The surface area and number density of these nanoclusters in NF-ODS steels could alter the point defect fluxes to GBs. Analytical microscopy techniques were conducted to determine the role of grain boundary structure and nanocluster dispersion on the RIS response in irradiated F/M steels. Here, a 9 wt. % Cr model alloy which simulates the structure of commercially available steels and 14YWT NF-ODS alloy was irradiated under numerous conditions. Both alloys were investigated using STEM/EDS and GB misorientation analysis. Experimental results indicate a preferential segregation of Cr to specific GB misorientations in the model F/M steel. Findings in the NF-ODS alloy indicates the stability of nanoclusters within the alloy alters the concentration gradient of the point defects near irradiated GBs. Based on these results, new theories on the role of interfaces in irradiated F/M steels was developed including a rate theory model which accounts for the GB misorientation angle within the RIS model. These theories will stimulate the development of new F/M steels which are highly resistant to RIS while in-service.

  15. Radiation induced chemical activity at iron and copper oxide surfaces

    NASA Astrophysics Data System (ADS)

    Reiff, Sarah C.

    The radiolysis of three iron oxides, two copper oxides, and aluminum oxide with varying amounts of water were performed using gamma-rays and 5 MeV 4He ions. The adsorbed water on the surfaces was characterized using temperature programmed desorption and diffuse reflectance infrared spectroscopy, which indicated that all of the oxides had chemisorbed water on the surface. Physisorbed water was observed on the Fe2O 3 and Al2O3 surfaces as well. Molecular hydrogen was produced from adsorbed water only on Fe2O3 and Al 2O3, while the other compounds did not show any hydrogen production due to the low amounts of water on the surfaces. Slurries of varying amounts of water were also examined for hydrogen production, and they showed yields that were greater than the yield for bulk water. However, the yields of hydrogen from the copper compounds were much lower than those of the iron suggesting that the copper oxides are relatively inert to radiation induced damage to nearby water. X-ray diffraction measurements did not show any indication of changes to the bulk crystal structure due to radiolysis for any of the oxides. The surfaces of the oxides were analyzed using Raman spectroscopy and X-ray photoelectron spectroscopy (XPS). For the iron samples, FeO and Fe3O4, Raman spectroscopy revealed areas of Fe2O3 had formed following irradiation with He ions. XPS indicated the formation of a new oxygen species on the iron oxide surfaces. Raman spectroscopy of the copper oxides did not reveal any changes in the surface composition, however, XPS measurements showed a decrease in the amount of OH groups on the surface of Cu2O, while for the CuO samples the amount of OH groups were found to increase following radiolysis. Pristine Al2O3 showed the presence of a surface oxyhydroxide layer which was observed to decrease following radiolysis, consistent with the formation of molecular hydrogen.

  16. 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 chemotherapy alone, surgery alone, and surgery plus chemotherapy was 17.3% and 17.3%, 56.6% and 50.3%, and 71.0% and 68.3%, respectively (p < 0.0001, log-rank test). Conclusion: The type of treatment for R-OS was the most significant factor for cause-specific and overall survival. Patients who develop R-OS should be aggressively treated, because the outcome is not as dismal as once thought.

  17. Radiation-Induced Damage to Nucleic Acid Constituents

    NASA Astrophysics Data System (ADS)

    Kim, Heasook

    The objective of this research was to identify the primary free radical species produced by ionizing radiation in DNA. The ultimate goal would be to use these data obtained from model compounds to analyze radiation-induced damage in DNA itself. The different single crystals were studied in detail. The first was the sodium salt of guanosine-3 ^':5^' -cyclic monophosphate (cyclic GMP). The results of studies on crystals irradiated at 4.2^ circK distinguished two species. One of these species exhibited a non-exchangeable proton coupling that was characterized by ENDOR spectroscopy and shown to be sigma proton. The spin density on C8 was deduced from the ENDOR hyperfine coupling tensor and found to be 0.15. The second species also exhibited a non-exchangeable sigma proton coupling and a beta proton coupling. The spin densities on C8 and N9 were deduced from ENDOR measurements to be 0.09 and 0.36. The former is attributed to the oxidation product and the latter to the primary reduction product. These products are respectively the guanine cation and anion. The second single crystal studied was a sodium salt of 2^'-deoxyguanosine -5^'-monophosphate tetrahydrate. The ESR and ENDOR spectra obtained from this crystal after x-irradiation at 4.2^circK were complex and the paramagnetic species were tentatively identified as ionic species. The third DNA model compound studied was thymidine. Single crystal of thymidine were irradiated at 1.6^ circK and at 4.2^circ K. The lower temperature preserved a more primitive stage of the radiation damage process. ENDOR measurements distinguished three paramagnetic species. The most interesting component of the paramagnetic absorption in crystals irradiated at 1.6^circK is attributed to trapped electron. These electrons are stabilized by the electrostatic fields generated by hydroxy dipoles. The hyperfine couplings between the trapped electron and the proton of these polar groups were deduced from ENDOR measurements. The ESR and ENDOR measurements described in this report were carried out DNA model compounds x-irradiated and measured at lower temperatures than reported previously. The experiments have demonstrated that an earlier stage of radiation damage can sometimes be stabilized and characterized in single crystals by maintaining the sample at 1.4 ^circK. (Abstract shortened with permission of author.).

  18. 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.

  19. 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 contrast, the distributions of RIF obtained as early as 5 min after exposure to high LET (1 GeV/amu Fe) were non-random. This deviation from the expected DNA-weighted random pattern was further characterized by "relative DNA image measurements". This novel imaging approach showed that RIF were located preferentially at the interface between high and low DNA density regions, and were more frequent than predicted in regions with lower DNA density. The same preferential nuclear location was also measured for RIF induced by 1 Gy of low-LET radiation. This deviation from random behavior was evident only 5 min after irradiation for phosphorylated ATM RIF, while γH2AX and 53BP1 RIF showed pronounced deviations up to 30 min after exposure. These data suggest that RIF within a few minutes following exposure to radiation cluster into open regions of the nucleus (i.e. euchromatin). It is possible that DNA lesions are collected in these nuclear sub-domains for more efficient repair. If so, this would imply that DSB are actively transported within the nucleus, a phenomenon that has not yet been considered in modeling DNA misrepair following exposure to radiation. These results are thus critical for more accurate risk models of radiation and we are actively working on characterizing further RIF movement in human nuclei using live cell imaging.

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

    SciTech Connect

    Jones, Keith W.

    1999-09-01

    Elemental analysis using emission of characteristic x rays is a well-established scientific method. The success of this analytical method is highly dependent on the properties of the source used to produce the x rays. X-ray tubes have long existed as a principal excitation source, but electron and proton beams have also been employed extensively. The development of the synchrotron radiation x-ray source that has taken place during the past 40 years has had a major impact on the general field of x-ray analysis. Even tier 40 years, science of x-ray analysis with synchrotron x-ray beams is by no means mature. Improvements being made to existing synchrotron facilities and the design and construction of new facilities promise to accelerate the development of the general scientific use of synchrotron x-ray sources for at least the next ten years. The effective use of the synchrotron source technology depends heavily on the use of high-performance computers for analysis and theoretical interpretation of the experimental data. Fortunately, computer technology has advanced at least as rapidly as the x-ray technology during the past 40 years and should continue to do so during the next decade. The combination of these technologies should bring about dramatic advances in many fields where synchrotron x-ray science is applied. It is interesting also to compare the growth and rate of acceptance of this particular research endeavor to the rates for other technological endeavors. Griibler [1997] cataloged the time required for introduction, diffusion,and acceptance of technological, economic, and social change and found mean values of 40 to 50 years. The introduction of the synchrotron source depends on both technical and non-technical factors, and the time scale at which this seems to be occurring is quite compatible with what is seen for other major innovations such as the railroad or the telegraph. It will be interesting to see how long the present rate of technological change 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.

  1. 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. PMID:23804237

  2. Brachial plexus endoscopic dissection and correlation with open dissection.

    PubMed

    Lafosse, T; Masmejean, E; Bihel, T; Lafosse, L

    2015-12-01

    Shoulder endoscopy is evolving and becoming extra-articular. More and more procedures are taking place in the area of the brachial plexus (BP). We carried out an anatomical study to describe the endoscopic anatomy of the BP and the technique used to dissect and expose the BP endoscopically. Thirteen fresh cadavers were dissected. We first performed an endoscopic dissection of the BP, using classical extra-articular shoulder arthroscopy portals. Through each portal, we dissected as many structures as possible and identified them. We then did an open dissection to corroborate the endoscopic findings and to look for damage to the neighboring structures. In the supraclavicular area, we were able to expose the C5, C6 and C7 roots, and the superior and middle trunks in 11 of 13 specimens through two transtrapezial portals by following the suprascapular nerve. The entire infraclavicular portion of the BP (except the medial cord and its branches) was exposed in 11 of 13 specimens. The approach to the infraclavicular portion of the BP led directly to the lateral and posterior cords, but the axillary artery hid the medial cord. The musculocutaneous nerve was the first nerve encountered when dissecting medially from the anterior aspect of the coracoid process. The axillary nerve was the first nerve encountered when following the anterior border of the subscapularis medially from the posterior aspect of the coracoid process. Knowledge of the endoscopic anatomy of the BP is mandatory to expose and protect this structure while performing advanced arthroscopic shoulder procedures. PMID:26585998

  3. Brachial and central blood pressure in HIV-infected subjects.

    PubMed

    Maloberti, Alessandro; Dozio, Dario; Betelli, Mauro; Bandera, Alessandra; Squillace, Nicola; Gori, Andrea; Castoldi, Giovanna; Stella, Andrea; Mancia, Giuseppe; Giannattasio, Cristina

    2015-06-01

    HIV infected subjects present an unfavorable cardiovascular (CV) risk profile that is determined by the infection itself, highly active anti-retroviral therapy (HAART) and other factors, such as chronic kidney disease (CKD). Information is scant and contradictory on whether these factors are associated with arterial stiffness and blood pressure (BP) alteration. Our study aimed to evaluate those parameters in HIV-positive subjects both with and without HAART and with and without CKD, which was defined as the presence of microalbuminuria with a normal glomerular filtration rate. We enrolled 94 HIV-infected subjects without known CV risk factors and compared them with 37 control subjects. We recorded brachial and central BP (pulse wave analysis) and pulse wave velocity ( SphygmoCor). HIV-positive subjects of similar ages and with similar BP values showed central pulse pressure values that were significantly greater than those of controls; this was also the case for the Aix value. Central systolic and pulse pressure values and Aix were significantly greater in HIV-positive subjects with HAART and CKD than in the other HIV-positive subgroups and control subjects. PWV was also superimposable between groups when the data were analyzed relative to the presence of HAART and CKD. Our study shows that the unfavorable CV risk profile associated with HIV infection includes an increase in both central BP and Aix. The central BP increase seems to be favored by renal damage, which apparently has a role in the early stages of the disease. PMID:25740293

  4. Birth Weight and Incidence of Surgical Obstetric Brachial Plexus Injury

    PubMed Central

    Nath, Rahul K.; Avila, Meera B.; Melcher, Sonya E.; Eichhorn, Mitchell G.; Somasundaram, Chandra

    2015-01-01

    Objectives: (1) To analyze the birth weight of obstetric brachial plexus injury (OBPI) patients requiring one or more reconstructive surgeries and (2) to analyze whether there is any difference in the severity of the injury, and the outcome of the surgery between the macrosomic and nonmacrosomic OBPI patients. Study Design: An observational cohort study was performed on 100 consecutive patients treated with surgery at the Texas Nerve and Paralysis Institute. Ninety of the 100 patients underwent the modified Quad surgery, which improves the shoulder abduction and overall shoulder function. All OBPI patients in our study were assessed preoperatively and postoperatively by evaluating video recordings of active shoulder abduction. Results: Using a 4000 g definition of macrosomia, 52% of patients would be considered macrosomic, and using a 4500 g definition of macrosomia, 18% of patients are considered macrosomic in our study. Permanent injury occurs also in average-birth-weight children. Conclusions: A significant percentage (48%-82% depending on definition of macrosomia) of OBPI patients requiring major reconstructive surgery had birth weights which would put them in the “normal” birth weight category. In addition, we found that there was no significant difference in the severity of the injury, and the outcome of the modified Quad surgical procedure between macrosomic and nonmacrosomic OBPI patients. However, there was a significant improvement in shoulder movement in both macrosomic and nonmacrosomic patients after modified Quad surgery. PMID:25987939

  5. 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.

  6. Brachial-to-radial systolic blood pressure amplification in patients with type 2 diabetes mellitus.

    PubMed

    Climie, R E D; Picone, D S; Keske, M A; Sharman, J E

    2016-06-01

    Brachial-to-radial-systolic blood pressure amplification (Bra-Rad-SBPAmp) can affect central SBP estimated by radial tonometry. Patients with type 2 diabetes mellitus (T2DM) have vascular irregularities that may alter Bra-Rad-SBPAmp. By comparing T2DM with non-diabetic controls, we aimed to determine the (1) magnitude of Bra-Rad-SBPAmp; (2) haemodynamic factors related to Bra-Rad-SBPAmp; and (3) effect of Bra-Rad-SBPAmp on estimated central SBP. Twenty T2DM (64±8 years) and 20 non-diabetic controls (60±8 years; 50% male both) underwent simultaneous cuff deflation and two-dimensional ultrasound imaging of the brachial and radial arteries. The first Korotkoff sound (denoting SBP) was identified from the first inflection point of Doppler flow during cuff deflation. Bra-Rad-SBPAmp was calculated by radial minus brachial SBP. Upper limb and systemic haemodynamics were recorded by tonometry and ultrasound. Radial SBP was higher than brachial SBP for T2DM (136±19 vs 127±17 mm Hg; P<0.001) and non-diabetic controls (135±12 vs 121±11 mm Hg; P<0.001), but Bra-Rad-SBPAmp was significantly lower in T2DM (9±8 vs 14±7 mm Hg; P=0.042). The product of brachial mean flow velocity × brachial diameter was inversely and independently correlated with Bra-Rad-SBPAmp in T2DM (β=-0.033 95% confidence interval -0.063 to -0.004, P=0.030). When radial waveforms were calibrated using radial, compared with brachial SBP, central SBP was significantly higher in both groups (T2DM, 116±13 vs 125±15 mm Hg; and controls, 112±10 vs 124±11 mm Hg; P<0.001 both) and there was a significant increase in the number of participants classified with 'central hypertension' (SBP⩾130 mm Hg; P=0.004). Compared with non-diabetic controls, Bra-Rad-SBPAmp is significantly lower in T2DM. Regardless of disease status, radial SBP is higher than brachial SBP and this results in underestimation of central SBP using brachial-BP-calibrated radial tonometry. PMID:26446391

  7. 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

  8. 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.

  9. 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

  10. The Extent of Blockade Following Axillary and Infraclavicular Approaches of Brachial Plexus Block in Uremic Patients

    PubMed Central

    Sariguney, Damla; Mahli, Ahmet; Coskun, Demet

    2012-01-01

    Introduction This study was aimed to compare the axillary approach performed through multiple injection method and vertical infraclavicular approach performed through single injection method in terms of the sensory and motor block onset, quality, and extent of blocks of brachial plexus in uremic patients who underwent arteriovenous fistula surgery. Methods Forty patients scheduled for creation of arteriovenous fistula with axillary brachial plexus block (group AX, n = 20) or infraclavicular brachial plexus block (IC group, n = 20) were examined. The median, radial, ulnar, and musculocutaneous nerves were selectively localized by nerve stimulation. The volume of the local anesthetics was calculated based on the height of each patient, and the volume determined was prepared by mixing 2% lidocaine and 0.5% bupivacaine in equal proportions. Sensory and motor block were assessed at 3, 6, 9, 12, 15, 18, and 30th min and their durations were measured. Results While the adequate sensory and motor block rate with axillary approach was 100% in musculocutaneous, median, radial, ulnar and medial antebrachial cutaneous nerves, it was 65% in axillary nerve, 80% in intercostobrachial nerve and 95% in medial brachial cutaneous nerve. This rate was found to be 100% for all the nerves with infraclavicular approach. Conclusion For arteriovenous fistula surgeries in uremic patients, both axillary approach performed through multiple injection method and vertical infraclavicular approach performed through single injection method can be used successfully; however, for the short performance of the procedure, infraclavicular block may be preferred. Keywords Brachial plexus block; Axillary; Infraclavicular; Uremic patients PMID:22383924

  11. Blueberry anthocyanins ameliorate radiation-induced lung injury through the protein kinase RNA-activated pathway.

    PubMed

    Liu, Yunen; Tan, Dehong; Tong, Changci; Zhang, Yubiao; Xu, Ying; Liu, Xinwei; Gao, Yan; Hou, Mingxiao

    2015-12-01

    The purpose of this study was to explore the effect of blueberry anthocyanins (BA) on radiation-induced lung injury and investigate the mechanism of action. Seven days after BA(20 and 80 mg/kg/d)administration, 6 weeks old male Sprague-Dawley rats rats were irradiated by LEKTA precise linear accelerator at a single dose of 20 Gy only once. and the rats were continuously treated with BA for 4 weeks. Moreover, human pulmonary alveolar epithelial cells (HPAEpiC) were transfected with either control-siRNA or siRNA targeting protein kinase R (PKR). Cells were then irradiated and treated with 75 μg/mL BA for 72 h. The results showed that BA significantly ameliorated radiation-induced lung inflammation, lung collagen deposition, apoptosis and PKR expression and activation. In vitro, BA significantly protected cells from radiation-induced cell death through modulating expression of Bcl-2, Bax and Caspase-3. Suppression of PKR by siRNA resulted in ablation of BA protection on radiation-induced cell death and modulation of anti-apoptotic and pro-apoptotic proteins, as well as Caspase-3 expression. These findings suggest that BA is effective in ameliorating radiation-induced lung injury, likely through the PKR signaling pathway. PMID:26551926

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

    PubMed

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

    2015-05-01

    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. PMID:25797627

  13. 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.

  14. 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…

  15. 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…

  16. Outcome in adolescence of brachial plexus birth palsy

    PubMed Central

    Hulleberg, Gunn; Elvrum, Ann-Kristin G; Brandal, Merethe; Vik, Torstein

    2014-01-01

    Background and purpose — The frequency and severity of a permanent lesion after brachial plexus birth palsy (BPBP) and its impact on activities of daily living are not well documented. We therefore investigated the outcome of BPBP in adolescents, regarding arm function and consequences for activity and participation. Participants and methods — Of 30,574 babies born at St. Olavs University Hospital in 1991–2000, 91 had BPBP (prevalence 3 per 1,000), and 69 of these individuals were examined at a median age of 14 (10–20) years. The examination included the modified Mallet classification, range of motion, shoulder rotation and grip strength, Assisting Hand Assessment, and Canadian Occupational Performance Measure. Of the 22 subjects who were not examined, 3 could not be traced and 19 reported having no problems in the affected arm. Results — At follow-up, 17 adolescents had a permanent lesion (i.e. individual Mallet subscore below 4) with a median Mallet total score of 15 (9–19), while 52 had good or normal shoulder function (median Mallet total score 25 (23–25)). All participants with a permanent lesion had reduced active shoulder rotation (≤ 15°), 16 had elbow extension deficit, and 10 had subnormal grip strength. External rotation was considerably weaker in the affected shoulder. In addition, they had ineffective use of the affected arm in bimanual activities. Even so, all except 1 were independent in activities of daily living, although 15 experienced minor difficulties. Interpretation — Every fourth to fifth child with BPBP had a permanent lesion as an adolescent. External rotation was the most impaired movement. Despite ineffective use of the affected arm in bimanual activities, all of the participants except one were independent in activities of daily living. PMID:25238434

  17. Atomic scale investigation of radiation-induced segregation in austenitic stainless steels

    NASA Astrophysics Data System (ADS)

    Etienne, A.; Radiguet, B.; Cunningham, N. J.; Odette, G. R.; Pareige, P.

    2010-11-01

    Radiation-induced precipitation and segregation in a cold-worked 316 austenitic stainless steel irradiated with 10 MeV Fe 5+ ions were characterized by atom probe tomography. Ni and Si enrichment and Cr depletion were observed in roughly spherical and torus-shaped clusters, believed to be due to solute enrichment and depletion at dislocation loops. Solute segregation was also observed at network dislocations. These observations are consistent with the phenomenon of radiation-induced segregation. Radiation-induced segregation at grain boundaries was also studied at the near atomic scale. Comparison of these observations with results from the literature shows a difference in the magnitude of the peak concentration of segregated solutes.

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

    PubMed

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

    2003-09-01

    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. PMID:12947391

  19. 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.

  20. Use of the bulbocavernosus muscle (Martius procedure) for repair of radiation-induced rectovaginal fistulas

    SciTech Connect

    White, A.J.; Buchsbaum, H.J.; Blythe, J.G.; Lifshitz, S.

    1982-07-01

    Radiation-induced fistulas of the vagina are rare, occurring in only 1 of 3% of patients treated for cancer of the uterine cervix. Primary surgical repair of these fistulas is usually unsuccessful because the defect is a result of devascularization. This type of radiation injury results from endarteritis obliterans, and successful repair requires an accessory blood supply. From 1971 to 1980, the authors performed 14 Martius procedures on 12 patients with radiation-induced rectovaginal fistulas. Eleven patients had successful closure of their fistulas using this procedure, and no operative complications occurred. The Martius procedure is effective for most radiation-induced vaginal fistulas, and the operation is well tolerated by most patients.

  1. The use of a catheter to provide brachial plexus block in dogs.

    PubMed Central

    Moens, N M; Caulkett, N A

    2000-01-01

    The objective of the study was to devise a method to facilitate catheter placement to perform brachial plexus block in the dog. Lidocaine plus epinephrine was injected through a 3.5 French feeding tube secured in proximity of the brachial plexus. Cutaneous areas for the nerves of the distal forelimb were tested for nociceptive sensation by pinching the skin with hemostats. Five out of the 7 dogs developed a full motor and sensory block. The onset time for a full block and duration of blockade were 54 min, s = 17.1 and 39 min, s = 37.6, respectively. A second blockade was successfully achieved in 2 dogs in which the catheter was not displaced. An indwelling feeding tube is an effective way to provide blockade of the brachial plexus in the dog. The placement and the fixation of the catheter were critical for the production of a full block. PMID:10992985

  2. 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

  3. The use of a catheter to provide brachial plexus block in dogs.

    PubMed

    Moens, N M; Caulkett, N A

    2000-09-01

    The objective of the study was to devise a method to facilitate catheter placement to perform brachial plexus block in the dog. Lidocaine plus epinephrine was injected through a 3.5 French feeding tube secured in proximity of the brachial plexus. Cutaneous areas for the nerves of the distal forelimb were tested for nociceptive sensation by pinching the skin with hemostats. Five out of the 7 dogs developed a full motor and sensory block. The onset time for a full block and duration of blockade were 54 min, s = 17.1 and 39 min, s = 37.6, respectively. A second blockade was successfully achieved in 2 dogs in which the catheter was not displaced. An indwelling feeding tube is an effective way to provide blockade of the brachial plexus in the dog. The placement and the fixation of the catheter were critical for the production of a full block. PMID:10992985

  4. Radiation induces autophagic cell death via the p53/DRAM signaling pathway in breast cancer cells.

    PubMed

    Cui, Li; Song, Zhiheng; Liang, Bing; Jia, Lili; Ma, Shumei; Liu, Xiaodong

    2016-06-01

    Autophagy is known to play a role in the response of breast cancer cells to radiation therapy. However, the mechanisms that mediate the process of autophagy and contribute to radiation-induced cell death and cell survival remain to be fully characterized. Therefore, in this study, the functional role of autophagy in radiation-induced cytotoxicity in breast cancer cells was investigated. After MCF-7 cells were exposed to various doses of radiation, increased monodansylcadaverine (MDC) staining and a greater deposition of LC3-positive puncta were observed. Expression of the autophagy-related proteins, Beclin 1 and LC3-II, were also found to be upregulated. Radiation-induced autophagic cell death was partially abrogated following the administration of 3-methyladenine (3-MA) and in knockdown experiments of Atg5 and Beclin 1. In the gene microarray analysis performed after irradiation, a number of differentially expressed genes were identified. In particular, upregulation of both the mRNA and protein levels of the autophagy-related genes, DRAM and TIGAR, were detected. However, inhibition of autophagy by 3-MA reduced the radiation-induced upregulation of LC3-II and DRAM. Conversely, silencing of p53 downregulated the expression of LC3-II and DRAM following radiation. Silencing of DRAM reversed the upregulation of LC3-II and DRAM following radiation, partially blocked radiation-induced cell death, and no significant change in p53 expression was detected. Based on these results, the p53/DRAM signaling pathway appears to contribute to radiation-induced autophagic cell death in MCF-7 breast cancer cells. PMID:27109777

  5. 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 functions linked to actin cytoskeleton.

  6. Does C5 or C6 Radiculopathy Affect the Signal Intensity of the Brachial Plexus on Magnetic Resonance Neurography?

    PubMed Central

    Seo, Tae Gyu; Kim, In-Soo; Son, Eun Seok

    2016-01-01

    Patients with C5 or C6 radiculopathy complain of shoulder area pain or shoulder girdle weakness. Typical idiopathic neuralgic amyotrophy (INA) is also characterized by severe shoulder pain, followed by paresis of shoulder girdle muscles. Recent studies have demonstrated that magnetic resonance neurography (MRN) of the brachial plexus and magnetic resonance imaging (MRI) of the shoulder in patients with INA show high signal intensity (HSI) or thickening of the brachial plexus and changes in intramuscular denervation of the shoulder girdle. We evaluated the value of brachial plexus MRN and shoulder MRI in four patients with typical C5 or C6 radiculopathy. HSI of the brachial plexus was noted in all patients and intramuscular changes were observed in two patients who had symptoms over 4 weeks. Our results suggest that HSI or thickening of the brachial plexus and changes in intramuscular denervation of the shoulder girdle on MRN and MRI may not be specific for INA. PMID:27152289

  7. [A case of prednisolone therapy for radiation-induced hemorrhagic cystitis].

    PubMed

    Yanagi, Masato; Nishimura, Taiji; Kurita, Susumu; Lee, Chorsu; Kondo, Yukihiro; Yamazaki, Keiichi

    2011-05-01

    Hemorrhagic cystitis resulting from radiation to pelvic visceral malignant lesions often might be incurable and there have been no established definitive treatment. We experienced a case with severe radiation-induced hemorrhagic cystitis refractory to conventional therapy. The treatment with oral administration of prednisolone was performed and obtained a successful result. Gross hematuria disappeared in 2 weeks in this case. This experience suggested that oral administration of prednisolone could be considered the treatment for patients with radiation-induced hemorrhagic cystitis when usual treatments including transurethral electro-coagulation are unsuccessful. PMID:21846069

  8. 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.

  9. Effects of proton pre-irradiation on radiation induced conductivity of polyimide

    NASA Astrophysics Data System (ADS)

    Yue, Long; Wu, Yiyong; Sun, Chengyue; Shi, Yaping; Zhang, Yanqing

    2016-02-01

    As an important parameter to evaluate the charge/discharge behaviors, radiation induced conductive behaviors of proton pre-irradiated polyimide films were investigated. The results indicate that the proton pre-irradiation results in decrease down to three orders in radiation induced conductivity (RIC) of polyimide as the proton (60-110 keV) fluence is just 1×1014 p/cm2. Further analysis implies that, the dominate effect on the RIC degradation is proton pre-irradiation induced displacement damage, which results in the decomposition of pyromellitimide in polyimide.

  10. Pathophysiology of Radiation-Induced Dysphagia in Head and Neck Cancer.

    PubMed

    King, Suzanne N; Dunlap, Neal E; Tennant, Paul A; Pitts, Teresa

    2016-06-01

    Oncologic treatments, such as curative radiotherapy and chemoradiation, for head and neck cancer can cause long-term swallowing impairments (dysphagia) that negatively impact quality of life. Radiation-induced dysphagia comprised a broad spectrum of structural, mechanical, and neurologic deficits. An understanding of the biomolecular effects of radiation on the time course of wound healing and underlying morphological tissue responses that precede radiation damage will improve options available for dysphagia treatment. The goal of this review is to discuss the pathophysiology of radiation-induced injury and elucidate areas that need further exploration. PMID:27098922

  11. Radiation-induced transmission loss in low water peak single mode fibers

    NASA Astrophysics Data System (ADS)

    Wang, Tingyun; Xiao, Zhongyin; Luo, Wenyun; Wen, Jianxiang; Yin, Jianchong; Wu, Wenkai; Gong, Renxiang

    2013-12-01

    Radiation-induced transmission loss in Low Water Peak Single Mode (LWPSM) fiber has been investigated. Formation and conversion processes of defect centers also have been proposed using electron spin resonance in the fiber irradiated with gamma rays. When the irradiation dose is low, Germanium electron center (GEC) and self-trapped hole center (STH) occur. With the increase of dose, E' centers (Si and Ge) and nonbridge oxygen hole centers (NBOHCs) generate. With the help of thermal-bleaching or photo-bleaching, the radiation-induced loss of pre-irradiation optical fiber can be reduced effectively. The obtain results also have been analyzed in detail.

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

    NASA Astrophysics Data System (ADS)

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

    2016-02-01

    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.

  13. Brachial Artery Aneurysm in a 7-Month-Old Infant: Case Report and Literature Review

    PubMed Central

    Gangopadhyay, Noopur; Chong, Tae; Chhabra, Avneesh

    2016-01-01

    Summary: Congenital upper extremity aneurysms are very rare and can be challenging to diagnose and treat. Although they can present as an isolated finding, they are often associated with other systemic conditions. We present a rare case of brachial artery aneurysm in a 7-month-old boy. The patient was evaluated with ultrasound, magnetic resonance angiography, and vein mapping before surgical reconstruction. After excision of the aneurysm, the brachial artery was reconstructed with an interposition saphenous vein graft. Because of potentially associated diagnoses and the possibility of concurrent aneurysms, this condition requires multidisciplinary management. PMID:27014554

  14. Brachial Plexus Injury as a Complication after Nerve Block or Vessel Puncture

    PubMed Central

    Kim, Hyun Jung; Park, Sang Hyun; Shin, Hye Young

    2014-01-01

    Brachial plexus injury is a potential complication of a brachial plexus block or vessel puncture. It results from direct needle trauma, neurotoxicity of injection agents and hematoma formation. The neurological presentation may range from minor transient pain to severe sensory disturbance or motor loss with poor recovery. The management includes conservative treatment and surgical exploration. Especially if a hematoma forms, it should be removed promptly. Comprehensive knowledge of anatomy and adept skills are crucial to avoid nerve injuries. Whenever possible, the patient should not be heavily sedated and should be encouraged to immediately inform the doctor of any experience of numbness/paresthesia during the nerve block or vessel puncture. PMID:25031806

  15. 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.

  16. The effect of Halofuginone in the amelioration of radiation induced-lung fibrosis.

    PubMed

    Yavas, Guler; Calik, Mustafa; Calik, Goknil; Yavas, Cagdas; Ata, Ozlem; Esme, Hidir

    2013-04-01

    The lung is one of the most sensitive organs to ionizing radiation, and damage to normal lung tissue remains a major dose limiting factor for patients receiving radiation to the thorax. Radiation induced lung injury (RILI) which is also named as "radiation pneumonpathy" is a continuous process and regarded as the result of an abnormal healing response. It has been shown that transforming growth factor β-1 (TGF-β1) plays an integral role in the radiation induced lung fibrosis formation by promoting the chemoattraction of fibroblasts and their conversion to myofibroblasts. Halofuginone is a, low molecular weight plant derived alkaloid, isolated from the Dichroa febrifuga plant that exhibits antifibrotic activity and inhibition of type I collagen synthesis. Halofuginone has been shown to protect against radiation induced soft tissue fibrosis by virtue of inhibiting various members of TFG-β signaling pathway. By the light of these findings, we hypothesize that Halofuginone may be able to ameliorate the radiation induced lung fibrosis. PMID:23352286

  17. 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

  18. Radiation-induced autophagy promotes esophageal squamous cell carcinoma cell survival via the LKB1 pathway.

    PubMed

    Lu, Chi; Xie, Conghua

    2016-06-01

    Radiotherapy is an important treatment modality for esophageal cancer; however, the clinical efficacy of radiotherapy is limited by tumor radioresistance. In the present study, we explored the hypothesis that radiation induces tumor cell autophagy as a cytoprotective adaptive response, which depends on liver kinase B1 (LKB1) also known as serine/threonine kinase 11 (STK11). Radiation-induced Eca-109 cell autophagy was found to be dependent on signaling through the LKB1 pathway, and autophagy inhibitors that disrupted radiation-induced Eca-109 cell autophagy increased cell cycle arrest and cell death in vitro. Inhibition of autophagy also reduced the clonogenic survival of the Eca-109 cells. When treated with radiation alone, human esophageal carcinoma xenografts showed increased LC3B and p-LKB1 expression, which was decreased by the autophagy inhibitor chloroquine. In vivo inhibition of autophagy disrupted tumor growth and increased tumor apoptosis when combined with 6 Gy of ionizing radiation. In summary, our findings elucidate a novel mechanism of resistance to radiotherapy in which radiation-induced autophagy, via the LKB1 pathway, promotes tumor cell survival. This indicates that inhibition of autophagy can serve as an adjuvant treatment to improve the curative effect of radiotherapy. PMID:27109915

  19. 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. PMID:26770116

  20. 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...

  1. 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...

  2. 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.

  3. 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.

  4. 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.

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

    PubMed Central

    Rannou, Emilie; Franois, Agns; Toullec, Aurore; Guipaud, Olivier; Buard, Valrie; 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

  6. 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.

  7. Use of iron colloid-enhanced MRI for study of acute radiation-induced hepatic injury

    SciTech Connect

    Suto, Yuji; Ametani, Masaki; Kato, Takashi; Hashimoto, Masayuki; Kamba, Masayuki; Sugihara, Syuji; Ohta, Yoshio

    1996-03-01

    We present a case with acute radiation-induced hepatic injury using chondroitin sulfate iron colloid (CSIC)-enhanced MRI. Uptake of CSIC was decreased in the irradiated portion of the liver. CSIC-enhanced MRI is useful for obtaining information on the function of the reticuloendothelial system and demarcates between irradiated and nonirradiated zones. 18 refs., 3 figs

  8. 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

  9. 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.

  10. 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).

  11. 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.

  12. 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

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

    PubMed

    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

  14. 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 on comparing agents and approaches that, in phase i and ii trials, suggest efficacy. These future phase iii randomized controlled trials must clearly distinguish between preventive and management strategies for radiation-induced dermatitis. Only then can evidence-based guidelines be developed, with the hope of standardizing the approach across centres and of improving the prevention and management of radiation-induced dermatitis. PMID:20697521

  15. 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

  16. The effect of perinatal brachial plexus lesion on upper limb development

    PubMed Central

    2014-01-01

    Background Deficiency in upper limb development is a sequel of the perinatal brachial plexus palsy. The purpose of this study was to evaluate the effect of brachial plexus birth lesion on upper limb development. Methods Forty-four patients with unilateral obstetric brachial plexus palsy underwent measurements of both upper extremities. The average age at the time of evaluation was 6.8 years. Active motion was assessed using Gilbert-Raimondi, the modified MRC, and Al-Qattan scales. Paired t test was used for statistical analysis. Correlation between limb length / circumference discrepancy and age / time of surgery was assessed using Pearson correlation coefficient. Results A decrease in the circumference and length was observed in all limbs with brachial plexus lesion. We found a statistically significant difference between degree of hand length and width decrease and its useful and useless function. We observed a statistically significant difference in measurement: forearm length, hand length and width dependent on the type of surgical procedure (neurolysis, reconstruction). We observed no correlation between age and limb length / circumference discrepancy. We also observed no correlation between time of surgery and limb length / circumference discrepancy. Conclusions The decrease in dimensions of the affected limbs occurred predominantly during the period of early childhood. Disparities in dimensions are observed in both cases of deficiency of useful function of upper limb and cases in which functional efficiency appears. PMID:24694070

  17. Changes in Spinal Cord Architecture after Brachial Plexus Injury in the Newborn

    ERIC Educational Resources Information Center

    Korak, Klaus J.; Tam, Siu Lin; Gordon, Tessa; Frey, Manfred; Aszmann, Oskar C.

    2004-01-01

    Obstetric brachial plexus palsy is a devastating birth injury. While many children recover spontaneously, 20-25% are left with a permanent impairment of the affected limb. So far, concepts of pathology and recovery have focused on the injury of the peripheral nerve. Proximal nerve injury at birth, however, leads to massive injury-induced…

  18. The Association of Homocysteine and Related Factors to Brachial Artery Diameter and Flow-Mediated Dilation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Brachial artery flow-mediated dilation (BAFMD) has been proposed as a measurement of the degree and severity of cardiovascular disease. The purpose of this study was to (1) evaluate the associations between BAFMD and homocysteine, folate, vitamin B12, vitamin B6, (2) examine the influence of 5,10-me...

  19. Ultrasound Guided Low Approach Interscalene Brachial Plexus Block for Upper Limb Surgery

    PubMed Central

    Park, Sun Kyung; Sung, Min Ha; Suh, Hae Jin

    2016-01-01

    Background The interscalene brachial plexus block is widely used for pain control and anesthetic purposes during shoulder arthroscopic surgeries and surgeries of the upper extremities. However, it is known that interscalene brachial plexus block is not appropriate for upper limb surgeries because it does not affect the lower trunk (C8-T1, ulnar nerve) of the brachial plexus. Methods A low approach, ultrasound-guided interscalene brachial plexus block (LISB) was performed on twenty-eight patients undergoing surgery of the upper extremities. The patients were assessed five minutes and fifteen minutes after the block for the degree of block in each nerve and muscle as well as for any complications. Results At five minutes and fifteen minutes after the performance of the block, the degree of the block in the ulnar nerve was found to be 2.8 ± 2.6 and 1.1 ± 1.8, respectively, based on a ten-point scale. Motor block occurred in the median nerve after fifteen minutes in 26 of the 28 patients (92.8%), and in all of the other three nerves in all 28 patients. None of the patients received additional analgesics, and none experienced complications. Conclusions The present study confirmed the achievement of an appropriate sensory and motor block in the upper extremities, including the ulnar nerve, fifteen minutes after LISB, with no complications. PMID:26839666

  20. The technique comparison of brachial plexus blocks by ultrasound guided with blocks by nerve stimulator guided

    PubMed Central

    Liu, Guo-Ying; Chen, Zhen-Qiang; Jia, Hai-Yan; Dai, Zhi-Gang; Zhang, Xue-Jun

    2015-01-01

    Objective: Brachial plexus perineural blocks provide specific analgesia for upper limb surgery. We present our experience with ultrasound-guided supraclavicular brachial plexus perineural blocks for distal upper limb surgery. Although single-injection ultrasound-guided supraclavicular blocks have been reported, little is known about the advantages using this approach compared with nerve stimulator guided. Methods: There were 60 patients who underwent upper limb surgery for orthopedic trauma and received a supraclavicular brachial plexus anesthesia. 30 patients (U-group) were injected by an ultrasound-guided technique with the needle tip remaining under direct vision. 30 patients (NS-group) were inserted by nerve stimulator guided. Recorded the onset time, puncture times, pains cases with tourniquet in each group. Compared the difference between two groups. Results: In U-group, all cases had successful perineural injection. Most of them, effect of anesthesia was fast onset and needed insert only once. No pains were reported under using tourniquet. There were no vessel punctures or other direct procedure-related complications. In NS-group, most injections were successful, but slow onset and needed multiply insert needle. 5 patients said pains under using tourniquet when surgery started and had to add opioid by vein. One patients’ lung were puncture and result in pneumothorax. One patient’s was intravascular injection. Conclusions: Supraclavicular brachial plexus perineural insertion using ultrasound guidance is feasible and almost have no complications, deserves further study with a randomized controlled trial comparing this relatively new technique with only using nerve stimulator. PMID:26629206

  1. Does the Addition of Tramadol and Ketamine to Ropivacaine Prolong the Axillary Brachial Plexus Block?

    PubMed Central

    Senel, Ahmet Can; Ukinc, Ozlem; Timurkaynak, Alper

    2014-01-01

    Background and Objectives. A prospective, randomized, controlled, double-blind clinical trial to assess the effect of tramadol and ketamine, 50 mg, added to ropivacaine in brachial plexus anesthesia. Methods. Thirty-six ASA physical statuses I and II patients, between 18 and 60 years of age, scheduled for forearm and hand surgery under axillary brachial plexus block, were allocated to 3 groups. Group R received 0.375% ropivacaine in 40 mL, group RT received 0.375% ropivacaine in 40 mL with 50 mg tramadol, and group RK received 0.375% ropivacaine in 40 mL with 50 mg ketamine for axillary brachial plexus block. The onset times and the duration of sensory and motor blocks, duration of analgesia, hemodynamic parameters, and adverse events (nausea, vomiting, and feeling uncomfortable) were recorded. Results. The onset time of sensorial block was the fastest in ropivacaine + tramadol group. Duration of sensorial and motor block was the shortest in the ropivacaine + tramadol group. Duration of analgesia was significantly longer in ropivacaine + tramadol group. Conclusion. We conclude that when added to brachial plexus analgesia at a dose of 50 mg, tramadol extends the onset and duration time of the block and improves the quality of postoperative analgesia without any side effects. PMID:24883319

  2. Brachial plexus injury management in military casualties: who, what, when, why, and how.

    PubMed

    Chambers, James A; Hiles, Claire L; Keene, Brian P

    2014-06-01

    The Global War on Terrorism has achieved an unprecedented 90% casualty survival rate because of far forward surgical support, rapid transport, and body armor. Despite the remarkable protection body armor affords, peripheral nerve injuries continue to occur. The brachial plexus in particular is still susceptible to penetrating trauma through the axilla as well as blunt mechanisms. We report 1,818 individuals with reported cases of peripheral nerve injury, 97 of which had brachial plexus injury incident from Operation Iraqi Freedom and Operation Enduring Freedom. We suspect that true prevalence is higher as initial focus on vascular and orthopedic reconstruction in complex shoulder injuries may overlook brachial plexus lesions. Accordingly, emergency physicians, general and orthopedic trauma surgeons, and vascular surgeons should all consider the possibility of brachial plexus and other peripheral nerve injury for early and appropriate referral to surgeons (plastic, orthopedic, or neurosurgical) for further evaluation and reconstruction. The latter group should be familiar with appropriate modern diagnostic and initial as well as salvage therapeutic options. PMID:24902131

  3. Validity of a new method to estimate mean arterial pressure at brachial level.

    PubMed

    Graf, Sebastian; Craiem, Damian; Armentano, Ricardo L

    2010-01-01

    The value of mean arterial pressure (MBP) is of clinical importance, and is required for peripheral resistance calculation as well as for central blood pressure calibration procedures. MBP is usually estimated at the upper arm using systolic and diastolic sphygmomanometers pressure values, as 33% of pulse pressure (PP) above diastolic pressure. In a previous work, we proposed to use 38%. The aim of this study was to investigate the validity of the proposed formula to calculate MBP, when assessing subjects with a wide range of blood pressure and pulse wave velocity (PWV) levels. In 73 volunteers (56 ± 10 years, range: 27-82; pulse pressure: 59 ± 12 mmHg, range: 43-86; PWV: 10 ± 2 m/s, range: 8-17) arterial pressure waveforms were obtained at the left brachial artery by applanation tonometry. Diastolic (DBP) and systolic (SBP) brachial pressure were obtained with oscillometric device. Brachial-radial PWV was obtained at the same arm using mechano-transducers. MBP computed as 38% of PP above diastolic pressure, introduces an error of only 0.1% in brachial MBP estimation, independent of pressure and PWV levels. PMID:21095973

  4. Luxation de lpaule complique de paralysie du plexus brachial

    PubMed Central

    Lukulunga, Loubet Unyendje; Moussa, Abdou Kadri; Mahfoud, Mustapha; EL Bardouni, Ahmed; Berrada, Mohamed Saleh; El Yaacoubi, Moradh

    2014-01-01

    Les auteurs rapportent l'observation d'une paralysie totale du plexus brachial survenue trois mois aprs un pisode de luxation antro-interne sous coracodienne associe une fracture du trochiter chez une patiente ge de 88 ans. PMID:25426187

  5. Journal of Nuclear Materials - Radiation-induced segregation and phase stability in ferritic-martensitic alloy T 91

    SciTech Connect

    Jiao, Zhijie; Busby, Jeremy T; Was, Gary S; Jiao, Zhijie

    2010-01-01

    Radiation-induced segregation in ferritic martensitic alloy T 91 was studied to understand the behavior of solutes as a function of dose and temperature. Irradiations were conducted using 2 MeV protons to doses of 1, 3, 7 and 10 dpa at 400 C. Radiation-induced segregation at prior austenite grain boundaries was measured, and various features of the irradiated microstructure were characterized, including grain boundary carbide coverage, the dislocation microstructure, radiation-induced precipitation and irradiation hardening. Results showed that Cr, Ni and Si segregate to prior austenite grain boundaries at low dose, but segregation ceases and redistribution occurs above 3 dpa. Grain boundary carbide coverage mirrors radiation-induced segregation. Irradiation induces formation of Ni Si Mn and Cu-rich precipitates that account for the majority of irradiation hardening. Radiation-induced segregation behavior is likely linked to the evolution of the precipitate and dislocation microstructures. 2010 Elsevier B.V. All rights reserved

  6. An epidemiological study of traumatic brachial plexus injury patients treated at an Indian centre

    PubMed Central

    Jain, Darshan Kumar A.; Bhardwaj, Praveen; Venkataramani, Hari; Sabapathy, S. Raja

    2012-01-01

    Background: Epidemiological studies on traumatic brachial plexus injuries are few and these studies help us to improve the treatment, rehabilitation of these patients and to allocate the resources required in their management. Epidemiological factors can vary in different countries. We wanted to know the situation in an Indian centre. Materials and Methods: Data regarding age, sex, affected side, mode of injury, distribution of paralysis, associated injuries, pain at the time of presentation and the index procedure they underwent were collected from 304 patients. Additional data like the vehicle associated during the accident, speed of the vehicle during the accident, employment status and integration into the family were collected in 144 patients out of the 304 patients. Results: Road traffic accidents accounted for 94% of patients and of the road traffic accidents 90% involved two wheelers. Brachial plexus injury formed a part of multitrauma in 54% of this study group and 46% had isolated brachial plexus injury. Associated injuries like fractures, vascular injuries and head injuries are much less probably due to the lower velocity of the vehicles compared to the western world. The average time interval from the date of injury to exploration of the brachial plexus was 127 days and 124 (40.78%) patients presented to us within this duration. Fifty-seven per cent had joined back to work by an average of 8.6 months. It took an average of 6.8 months for the global brachial plexus-injured patients to write in their non-dominant hand. PMID:23449838

  7. Automated plethysmographic measurement of the ankle-brachial index: a comparison with the doppler ultrasound method.

    PubMed

    Davies, Jane H; Williams, E Mark

    2016-02-01

    The ankle-brachial index is widely regarded as a pivotal tool for the diagnosis and quantification of peripheral arterial disease. It is, however, plagued by issues relating to its time consuming nature and the skills required to undertake its measurement using the gold standard Doppler ultrasound method. Automated ankle-brachial index measurement devices aim to address such issues; this study aimed to compare the performance of such a device with the Doppler method. Three hundred and eighty participants, with risk factors for cardiovascular disease (mean age: 64, 57% male), underwent ankle-brachial index measurement firstly with a plethysmographic device followed by the Doppler method. The mean difference between the two methods was 0.016±0.1, 95% limits of agreement:±0.2. Sensitivity for detection of peripheral arterial disease, as defined by Doppler ankle-brachial index⩽0.9, was 70%, specificity 96%, accuracy 94%. A receiver operating curve revealed an area under the curve of.96, with a 1.04 plethysmographic ankle-brachial index cutoff for optimal sensitivity (98%) and specificity (75%). Automated measurements were significantly faster than Doppler measurements (7 min 55 s vs. 17 min 45 s, respectively, P <0.01). Although is it unclear if the plethysmographic device has sufficient diagnostic accuracy to be used as a stand alone test for the diagnosis of peripheral arterial disease, it is concluded that it can be used as a fast and amenable method of identifying people who require further arterial assessment; the higher cutoff point of 1.04 should be used for this purpose. PMID:26631853

  8. Management of traumatic brachial artery injuries: A report on 49 patients

    PubMed Central

    Ekim, Hasan; Tuncer, Mustafa

    2009-01-01

    BACKGROUND AND OBJECTIVE: The brachial artery is the most frequently injured artery in the upper extremity due to its vulnerability. The purpose of our study was to review our experience with brachial artery injuries over a 9-year period, describing the type of injury, surgical procedures, complications, and associated injuries. PATIENTS AND METHODS: Forty-nine patients with brachial artery injury underwent surgical repair procedures at our hospital, from the beginning of May 1999 to the end of June 2008. The brachial artery injuries were diagnosed by physical examination and Doppler ultrasonography. Depending on the mode of presentation, patients were either taken immediately to the operating room for bleeding control and vascular repair or were assessed by preoperative duplex ultrasonography. RESULTS: This study group consisted of 43 males and 6 females, ranging in age from 6 to 65 years with a mean (SD) age of 27.9 (6.7) years. The mechanism of trauma was penetrating in 45 patients and blunt in the remaining 4 patients. Stab injury was the most frequent form of penetrating trauma (24 of 45). Treatment included primary arterial repair in 5 cases, end-to-end anastomosis in 28 cases, interposition vein graft in 15 cases, and interposition-ringed polytetrafluoroethylene graft in 1 case. Associated injuries were common and included venous injury (14), bone fracture (5), and peripheral nerve injury (11). Fifteen patients developed postoperative complications. One patient underwent an above-elbow amputation. CONCLUSIONS: Prompt and appropriate management of the brachial artery injuries, attention to associated injuries, and a readiness to revise the vascular repair early in the event of failure will maximize patient survival and upper extremity salvage. PMID:19318753

  9. 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.

  10. Gamma-radiation induced changes in the physical and chemical properties of lignocellulose.

    PubMed

    Khan, Ferdous; Ahmad, S R; Kronfli, E

    2006-08-01

    gamma-radiation induced effects on the physical and chemical properties of natural lignocellulose (jute) polymer were investigated. Samples were irradiated to required total doses at a particular dose rate. The changes in the parameters such as the tensile strength, elongation at break, and work done at rupture for the lignocellulose samples on irradiation with the gamma-rays from a cobalt-60 source were measured. The mechanical properties were found to have nonlinear relations with the radiation doses. The chemical stability of irradiated fibers was found to degrade progressively with the increase of radiation dose. Additionally, other chemical changes of the samples due to exposure to high-energy radiation were also investigated using fluorescence and infrared spectroscopic analysis. Differential scanning calorimetry and thermogravimetric studies showed a significant reduction in thermal stability. The wide-angle X-ray diffraction study showed that structural changes of cellulose appeared due to the radiation-induced chemical reaction of lignocellulose. PMID:16903675

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

    PubMed

    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

  12. Identification of a novel ionizing radiation-induced nuclease, AEN, and its functional characterization in apoptosis

    SciTech Connect

    Lee, Ji-Hyun; Koh, Yeon A.; Cho, Chul-Koo; Lee, Su-Jae; Lee, Yun-Sil; Bae, Sangwoo . E-mail: swbae@kcch.re.kr

    2005-11-11

    To investigate ionizing radiation response, we screened genes that exhibit higher expression following {gamma} irradiation. We report here the isolation and functional characterization of a novel ionizing radiation-induced gene, AEN. Sequence analysis of AEN revealed exonuclease domain highly similar to that of exonuclease III. The AEN protein revealed DNase activity by cleaving various DNA substrates. Subcellular distribution of AEN exhibited nuclear colocalization with apoptotic nucleases such as CAD and AIF following irradiation. Moreover AEN distribution revealed perinuclear staining pattern which could be seen with other apoptotic nucleases. Irradiation of AEN-expressing cells resulted in synergistic increase of apoptosis whereas AEN deletion mutant in exonuclease domain did not. Our data, thus, suggest that radiation-induced AEN cleaves DNA in concert with other apoptotic nucleases and thereby enhances apoptosis following ionizing irradiation.

  13. 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

  14. 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).

  15. In situ measurement of radiation induced conductivity in oxide insulators during neutron irradiation

    NASA Astrophysics Data System (ADS)

    White, D. P.; Snead, L. L.; Zinkle, S. J.; Eatherly, W. S.

    1998-02-01

    An experimental investigation of the in situ electrical conductivity of Wesgo Al995 polycrystalline alumina at approximately 450 °C has been performed at the high flux beam reactor at Brookhaven National Laboratory. The measured radiation induced conductivity (RIC) was about 10-8 S/m at an ionizing dose rate of 6000 Gy/s. No evidence for permanent radiation induced electrical degradation was observed for an applied electric field of 147 V/mm up to a dose level of ≈1.8 displacements per atom. The effect of neutron irradiation on the electrical properties of two mineral insulated cables was also investigated. The RIC in the MgO insulation of a coaxial and a triaxial cable was measured to be in the range of 6-20 ×10-8 S/m at an ionizing dose rate of ≈ 6000 Gy/s.

  16. 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.

  17. 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.

  18. 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.

  19. Effect of radiation induced deep level traps on Si detector performance

    NASA Astrophysics Data System (ADS)

    Eremin, V.; Verbitskaya, E.; Li, Z.

    2002-01-01

    The main factor, which leads to semiconductor detector degradation in high-energy physics experiments, is the introduction of lattice defects in the detector material produced by radiation. Based on the spectrum of radiation induced defects in the silicon bulk, the overview of effects and mechanisms responsible for the changes in the main detector parameters such as effective concentration of the space charge in the depleted region, space charge sign inversion, charge collection efficiency, and detector breakdown voltage are considered. Special attention is paid to the electric field distortion related with high concentration of radiation induced deep traps, which is the key question for the design of detectors operating at cryogenic temperature. In particular, the charge collection recovery at low temperature, often refereed as the Lazarus effect, and the limitation for the detection rate related to the polarization effect are considered.

  20. Low temperature diffusion of hydrogenic species in oxide crystals: Radiation induced diffusion

    SciTech Connect

    Chen, Y.; Gonzalez, R.

    1993-10-01

    Normally stable configurations of substitutional protons or deuterons in oxide crystal become highly unstable during ionizing radiation at room temperature, resulting in the displacements of these species. The cross section for radiation-induced-displacements of protons is exceedingly large and is a strong function of temperature. The displacement cross section of protons from cation sites is twice that of deuterons. Diffusion of these species can be induced at temperatures not otherwise possible by thermal means. For example, using electron irradiation near room temperature the O-H bond is readily broken and the hydrogenic species can be channeled along the c-axis in TiO{sub 2} by an applied electric field. Radiation induced displacements of protons from anion sites (hydride ions) at room temperature are also discussed.

  1. Radiation-induced stress change in polymers during irradiation by electrons

    SciTech Connect

    Barbashev, E.A.; Bogatov, V.A.; Kozin, V.I.; Panshin, B.I.

    1986-05-01

    The goal of this study is to experimentally validate equations previously used to describe a radiation-induced stress change (RSC) in polymers. Radiation-induced creep is due to the freeing of volumes of the material with the breakdown of a bond. With an increase in molecular mobility, the contribution of single defects to creep may be an appreciable fraction of the contribution of submicrocracks. According to the authors, this should lead to lessening of the temperature and force dependences of creep. All ruptured bonds, regardless of their load level, contribute to RSC in the degradation of stressed chemical bonds. Thus, the RSC reflects the gross process of breakdown of molecules. A change in the dose rate does not change the conditions of breakdown of stressed bonds, and there is no change in the dependence of the rate of degradation on dose rate for macromolecules with any stress.

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

    SciTech Connect

    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. . E-mail: chunt@radonc.wustl.edu

    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 15 Gy radiation. In mice exposed to 5 Gy 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.

  3. Comparison of Brachial Artery Vasoreactivity in Elite Power Athletes and Age-Matched Controls

    PubMed Central

    Welsch, Michael A.; Blalock, Paul; Credeur, Daniel P.; Parish, Tracie R.

    2013-01-01

    Elite endurance athletes typically have larger arteries contributing to greater skeletal muscle blood flow, oxygen and nutrient delivery and improved physical performance. Few studies have examined structural and functional properties of arteries in power athletes. Purpose To compare the size and vasoreactivity of the brachial artery of elite power athletes to age-matched controls. It was hypothesized brachial artery diameters of athletes would be larger, have less vasodilation in response to cuff occlusion, but more constriction after a cold pressor test than age-matched controls. Methods Eight elite power athletes (age = 23±2 years) and ten controls (age = 22±1 yrs) were studied. High-resolution ultrasonography was used to assess brachial artery diameters at rest and following 5 minutes of forearm occlusion (Brachial Artery Flow Mediated Dilation = BAFMD) and a cold pressor test (CPT). Basic fitness measures included a handgrip test and 3-minute step test. Results Brachial arteries of athletes were larger (Athletes 5.39±1.51 vs. Controls: 3.73±0.71 mm, p<0.05), had greater vasodilatory (BAFMD%: Athletes: 8.21±1.78 vs. Controls: 5.69±1.56%) and constrictor (CPT %: Athletes: -2.95±1.07 vs. Controls: −1.20±0.48%) responses, compared to controls. Vascular operating range (VOR = Peak dilation+Peak Constriction) was also greater in athletes (VOR: Athletes: 0.55±0.15 vs. Controls: 0.25±0.18 mm, p<0.05). Athletes had superior handgrip strength (Athletes: 55.92±17.06 vs. Controls: 36.77±17.06 kg, p<0.05) but similar heart rate responses at peak (Athletes: 123±16 vs. Controls: 130±25 bpm, p>0.05) and 1 minute recovery (Athletes: 88±21 vs. Controls: 98±26 bpm, p>0.05) following the step test. Conclusion Elite power athletes have larger brachial arteries, and greater vasoreactivity (greater vasodilatory and constrictor responses) than age-matched controls, contributing to a significantly greater VOR. These data extend the existence of an ‘athlete’s artery’ as previously shown for elite endurance athletes to elite power athletes, and presents a hypothetical explanation for the functional significance of the ‘power athlete’s artery’. PMID:23359214

  4. C/EBPδ Deficiency Sensitizes Mice to Ionizing Radiation-Induced Hematopoietic and Intestinal Injury

    PubMed Central

    Chang, Jianhui; Wang, Wenze; Pathak, Rupak; Zhu, Xiaoyan; Wang, Junru; Hendrickson, Howard; Boerma, Marjan; Sterneck, Esta; Zhou, Daohong; Hauer-Jensen, Martin

    2014-01-01

    Knowledge of the mechanisms involved in the radiation response is critical for developing interventions to mitigate radiation-induced injury to normal tissues. Exposure to radiation leads to increased oxidative stress, DNA-damage, genomic instability and inflammation. The transcription factor CCAAT/enhancer binding protein delta (Cebpd; C/EBPδ is implicated in regulation of these same processes, but its role in radiation response is not known. We investigated the role of C/EBPδ in radiation-induced hematopoietic and intestinal injury using a Cebpd knockout mouse model. Cebpd−/− mice showed increased lethality at 7.4 and 8.5 Gy total-body irradiation (TBI), compared to Cebpd+/+ mice. Two weeks after a 6 Gy dose of TBI, Cebpd−/− mice showed decreased recovery of white blood cells, neutrophils, platelets, myeloid cells and bone marrow mononuclear cells, decreased colony-forming ability of bone marrow progenitor cells, and increased apoptosis of hematopoietic progenitor and stem cells compared to Cebpd+/+ controls. Cebpd−/− mice exhibited a significant dose-dependent decrease in intestinal crypt survival and in plasma citrulline levels compared to Cebpd+/+ mice after exposure to radiation. This was accompanied by significantly decreased expression of γ-H2AX in Cebpd−/− intestinal crypts and villi at 1 h post-TBI, increased mitotic index at 24 h post-TBI, and increase in apoptosis in intestinal crypts and stromal cells of Cebpd−/− compared to Cebpd+/+ mice at 4 h post-irradiation. This study uncovers a novel biological function for C/EBPδ in promoting the response to radiation-induced DNA-damage and in protecting hematopoietic and intestinal tissues from radiation-induced injury. PMID:24747529

  5. 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.

  6. 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.

  7. Radiation-induced mobility of lithium and sodium in alpha-quartz

    SciTech Connect

    Hitt, K.B.; Martin, J.J.

    1983-09-01

    The radiation-induced release of the charge compensating ions Li/sup +/ and Na/sup +/ from the substitutional aluminum impurity in ..cap alpha..-quartz has been investigated by measuring the growth of the infrared active Al--OH/sup -/ center as a function of sample temperature during irradiation. It was found that Li/sup +/ is released 10--15 K lower in temperature than Na/sup +/.

  8. 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.

  9. 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

  10. 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.

  11. Gamma knife radiosurgery of radiation-induced intracranial tumors: Local control, outcomes, and complications

    SciTech Connect

    Jensen, Ashley W.; Brown, Paul D.; Pollock, Bruce E.; Stafford, Scott L.; Link, Michael J.; Garces, Yolanda I.; Foote, Robert L.; Gorman, Deborah A.; Schomberg, Paula J.

    2005-05-01

    Purpose: To determine local control (LC) and complication rates for patients who underwent radiosurgery for radiation-induced intracranial tumors. Methods and Materials: Review of a prospectively maintained database (2,714 patients) identified 16 patients (20 tumors) with radiation-induced tumors treated with radiosurgery between 1990 and 2004. Tumor types included typical meningioma (n = 17), atypical meningioma (n = 2), and schwannoma (n 1). Median patient age at radiosurgery was 47.5 years (range, 27-70 years). The median tumor margin dose was 16 Gy (range, 12-20 Gy). Median follow-up was 40.2 months (range, 10.8-146.2 months). Time-to-event outcomes were calculated with Kaplan-Meier estimates. Results: Three-year and 5-year LC rates were 100%. Three-year and 5-year overall survival rates were 92% and 80%, respectively. Cause-specific survival rates at 3 and 5 years were 100%. Three patients died: 1 had in-field progression 65.1 months after radiosurgery and later died of the tumor, 1 died of progression of a preexisting brain malignancy, and 1 died of an unrelated cause. One patient had increased seizure activity that correlated with development of edema seen on neuroimaging. Conclusions: LC, survival, and complication rates in our series are comparable to those in previous reports of radiosurgery for intracranial meningiomas. Also, LC rates with radiosurgery are at least comparable to those of surgical series for radiation-induced meningiomas. Radiosurgery is a safe and effective treatment option for radiation-induced intracranial tumors, most of which are typical meningiomas.

  12. 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.

  13. 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.

  14. Serum amyloid P ameliorates radiation-induced oral mucositis and fibrosis

    PubMed Central

    2010-01-01

    Purpose To evaluate the effect of the anti-fibrotic protein serum amyloid P (SAP) on radiation-induced oral mucositis (OM) and fibrosis in a hamster cheek-pouch model. Experimental Design Hamsters received a single dose of radiation (40 Gy) to the left everted cheek pouch to induce significant OM. The protective therapeutic potential of SAP was evaluated using varying dosing regimens. The extent of OM was measured using a validated six-point scoring scheme ranging from 0 (normal tissue, no mucositis) to 5 (complete ulceration). Fibrotic remodeling was also visualized histologically and quantified at later time points using collagen gene expression. Results SAP treatment attenuated the profile of radiation-induced oral mucositis by delaying the time of onset, reducing the peak value, and enhancing the resolution of injury. The peak mucositis score was reduced by approximately 0.5 grade in SAP-treated animals. The number of animal days with a score of ≥ 3 was reduced by 48% in the SAP-treated group, compared with the saline control group (P < 0.01). SAP also inhibited the extent of tissue remodeling and decreased radiation-induced increases in myofibroblast number. Attenuated collagen deposition and gene expression was also observed in the cheek pouches of hamsters treated with SAP at both 16 and 28 days post-radiation. Conclusions SAP treatment significantly attenuated radiation-induced injury. In particular, SAP attenuated the severity of OM and inhibited pathogenic remodeling. This suggests that SAP may be a useful therapy for the palliation of side effects observed during treatment for head and neck cancer. PMID:20602770

  15. 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.

  16. 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

  17. Recurrent brachial artery embolism caused by a crutch-induced axillary artery aneurysm: report of a case.

    PubMed

    Morisaki, Koichi; Kuma, Sosei; Okazaki, Jin

    2014-07-01

    We report a case of axillary artery aneurysm with brachial artery embolism in a 60-year-old man who had walked with the assistance of axillary crutches all of his life since poliomyelitis during infancy had left him with lower limb paralysis. We performed bypass grafting from the axillary to brachial artery with exclusion of the aneurysm. An axillary artery aneurysm is rare, but potentially lethal for the upper extremity; therefore, surgical treatment should be considered. PMID:23807637

  18. Biological dosimetry: the potential use of radiation-induced apoptosis in human T-lymphocytes.

    PubMed

    Menz, R; Andres, R; Larsson, B; Ozsahin, M; Trott, K; Crompton, N E

    1997-09-01

    An assay for biological dosimetry based on the induction of apoptosis in human T-lymphocytes is described. Radiation-induced apoptosis was assessed by flow cytometric identification of cells displaying apoptosis-associated DNA condensation. CD4 and CD8 T-lymphocytes were analysed. They were recognized on the basis of their cell-surface antigens. Four parameters were measured for both cell types: cell size, granularity, antigen immunofluorescence and DNA content. Apoptosis was quantified as the fraction of CD4-, or CD8-positive cells with a characteristic reduction of cell size and DNA content. At doses below 1 Gy, levels of radiation-induced apoptosis increased for up to 5 days after irradiation. Optimal dose discrimination was observed 4 days after irradiation, at which time the dose-response curves were linear, with a slope of 8% +/- 0.5% per 0.1 Gy. In controlled, dose-response experiments the lowest dose level at which the radiation-induced apoptosis frequency was still significantly above control was 0.05 Gy. After 5 days post-irradiation incubation, intra- and interdonor variations were measured and found to be similar; thus, apoptotic levels depend more on the dose than on the donor. The results demonstrate the potential of this assay as a biological dosimeter. PMID:9402634

  19. 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

  20. The Mechanism of Zr and Hf in Reducing Radiation-Induced Segregation in 316 Stainless Steel

    SciTech Connect

    Hackett, Micah J.; Busby, Jeremy T; Was, Gary

    2008-01-01

    The addition of oversized solutes has the potential to reduce the effects of radiation-induced segregation (RIS) in austenitic alloys. Radiation induced segregation has been implicated as one of several factors in enhancing stress corrosion cracking (SCC) under irradiation, so oversized solute additions could promote SCC resistance. Zr or Hf were added to 316-type stainless steel at levels between 0.05 at% and 0.37 at%. Samples were irradiated with 3 MeV protons to 3 dpa at 400 C, and analyzed in HR-STEM with EDS to measure the grain boundary composition. Zr additions substantially reduced the amount of RIS while Hf was much less effective. Despite similar sizes, first-principles calculations using VASP demonstrate that solute-vacancy binding for Zr is 1.05 eV vs. 0.69 eV for Hf. This difference results in a greater effectiveness of Zr in reducing radiation induced segregation as determined by kinetic rate theory calculations, in agreement with measured results.

  1. Mechanisms of radiation-induced normal tissue toxicity and implications for future clinical trials

    PubMed Central

    Jenrow, Kenneth A.; Brown, Stephen L.

    2014-01-01

    To summarize current knowledge regarding mechanisms of radiation-induced normal tissue injury and medical countermeasures available to reduce its severity. Advances in radiation delivery using megavoltage and intensity-modulated radiation therapy have permitted delivery of higher doses of radiation to well-defined tumor target tissues. Injury to critical normal tissues and organs, however, poses substantial risks in the curative treatment of cancers, especially when radiation is administered in combination with chemotherapy. The principal pathogenesis is initiated by depletion of tissue stem cells and progenitor cells and damage to vascular endothelial microvessels. Emerging concepts of radiation-induced normal tissue toxicity suggest that the recovery and repopulation of stromal stem cells remain chronically impaired by long-lived free radicals, reactive oxygen species, and pro-inflammatory cytokines/chemokines resulting in progressive damage after radiation exposure. Better understanding the mechanisms mediating interactions among excessive generation of reactive oxygen species, production of pro-inflammatory cytokines and activated macrophages, and role of bone marrow-derived progenitor and stem cells may provide novel insight on the pathogenesis of radiation-induced injury of tissues. Further understanding the molecular signaling pathways of cytokines and chemokines would reveal novel targets for protecting or mitigating radiation injury of tissues and organs. PMID:25324981

  2. 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.

  3. Mechanisms of radiation-induced normal tissue toxicity and implications for future clinical trials.

    PubMed

    Kim, Jae Ho; Jenrow, Kenneth A; Brown, Stephen L

    2014-09-01

    To summarize current knowledge regarding mechanisms of radiation-induced normal tissue injury and medical countermeasures available to reduce its severity. Advances in radiation delivery using megavoltage and intensity-modulated radiation therapy have permitted delivery of higher doses of radiation to well-defined tumor target tissues. Injury to critical normal tissues and organs, however, poses substantial risks in the curative treatment of cancers, especially when radiation is administered in combination with chemotherapy. The principal pathogenesis is initiated by depletion of tissue stem cells and progenitor cells and damage to vascular endothelial microvessels. Emerging concepts of radiation-induced normal tissue toxicity suggest that the recovery and repopulation of stromal stem cells remain chronically impaired by long-lived free radicals, reactive oxygen species, and pro-inflammatory cytokines/chemokines resulting in progressive damage after radiation exposure. Better understanding the mechanisms mediating interactions among excessive generation of reactive oxygen species, production of pro-inflammatory cytokines and activated macrophages, and role of bone marrow-derived progenitor and stem cells may provide novel insight on the pathogenesis of radiation-induced injury of tissues. Further understanding the molecular signaling pathways of cytokines and chemokines would reveal novel targets for protecting or mitigating radiation injury of tissues and organs. PMID:25324981

  4. Analysis of potential radiation-induced genetic and somatic effects to man from milling of uranium

    SciTech Connect

    Momeni, M.H.

    1984-01-01

    Potential mortality from natural causes and from radiation exposure conditions typical of those in the vicinity of uranium mills in the western USA was calculated. The exposure conditions were those assumed to exist in the vicinity of a hypothetical model mill. Dose rates to organs at risk were calculated as a function of time using the Uranium Dispersion and Dosimetry Code (Momeni et al. 1979). The changes in population size, birth rates, and radiation-induced and natural mortalities were calculated using the PRIM code (Momeni 1983). The population of the region within a radius of 80 km from the model mill is projected to increase from 57 428 to 75 638.6 during the 85 years of this analysis. Within the same period, the average birth rates for five-year periods increase from 5067.8 to 7436.1. The cumulative deaths within the five-year periods increase from 724 and 3501.8 from spontaneously induced neoplasms and all causes, respectively, to 1538.2 and 6718.2. In comparison to natural causes, radiation-induced mortality is negligible. The highest rate of death from radiation in any five-year period is only 0.2, compared with 1538.2 deaths attributable to spontaneous incidence. The total radiation-induced genetic disorders were much less than unity for the 85-year period of analysis, in contrast with the 10.7% natural incidence of these disorders.

  5. Solar-simulated ultraviolet radiation induces abnormal maturation and defective chemotaxis of dendritic cells.

    PubMed

    Mittelbrunn, Mara; Tejedor, Reyes; de la Fuente, Hortensia; Garca-Lpez, M Angeles; Ursa, Angeles; Peas, Pablo F; Garca-Dez, Amaro; Alonso-Lebrero, Jos Luis; Pivel, Juan Pablo; Gonzlez, Salvador; Gonzalez-Amaro, Roberto; Snchez-Madrid, Francisco

    2005-08-01

    Exposure to ultraviolet (UV) light induces immunosuppression. Different evidences indicate that this phenomenon is mainly a consequence of the effect of UV light on skin dendritic cells (DC). To investigate the cellular and molecular basis of this type of immunosuppression, we assessed in vitro the effect of solar-simulated UV radiation on the phenotypic and functional characteristics of human monocyte-derived DC and Langerhans-like DC. UV radiation induced a decreased expression of molecules involved in antigen capture as DC-SIGN and the mannose receptor. This effect was accompanied by a diminished endocytic capacity, an enhanced expression of molecules involved in antigen presentation such as major histocompatibility complex-II and CD86, and a significant increase in their capability to stimulate T cells. Furthermore, irradiated DC failed to acquire a full mature phenotype upon treatment with lipopolysaccharide. On the other hand, solar-simulated radiation induced the secretion of tumor necrosis factor-alpha and interleukin (IL)-10 by DC, but no IL-12. Interestingly, solar-simulated UV radiation also caused an altered migratory phenotype, with an increased expression of CXCR4, and a lack of induction of CCR7, thus correlating with a high chemotactic response to stromal cell-derived factor 1(SDF-1) (CXCL12), but not to secondary lymphoid tissue chemokine (SLC) (CCL21). These data indicate that solar-simulated UV radiation induces a defective maturation and an anomalous migratory phenotype of DC. PMID:16098045

  6. The effect of probiotics for preventing radiation-induced morphological changes in intestinal mucosa of rats.

    PubMed

    Ki, Yongkan; Kim, Wontaek; Cho, Heunglae; Ahn, Kijung; Choi, Youngmin; Kim, Dongwon

    2014-10-01

    Radiation therapy is an important treatment modality for abdominal or pelvic cancer, but there is a common and serious complication such as radiation-induced enteritis. Probiotics is reported to have positive effects against radiation-induced enteropathy. In this study, morphological changes of bowel mucosa were analyzed in rats to presume the effect of probiotics on radiation-induced enteritis and its correlation with radiation dose. A total of 48 adult male Sprague-Dawley rats were randomly assigned to two groups and received a solution containing 1.0×10(8) colony-forming units of Lactiobacillus acidophilus or water once daily for 10 days. Each of two groups was divided into three subgroups and abdomino-pelvic area of each subgroup was irradiated with 10, 15, and 20 Gy, respectively on the seventh day of feeding the solutions. All rats were sacrificed 3 days after irradiation and the mucosal thickness and villus height of jejunum, ileum and colon were measured. The morphological parameters of the small intestine represented significant differences between two solution groups irradiated 10 or 15 Gy, except for villus height of jejunum in 15 Gy-subgroup (P=0.065). There was no significant morphometric difference between two groups irradiated with 20 Gy of radiation. Probiotics appear to be effective for the morphological shortening of small intestinal mucosa damaged by radiation less than or equal to 15 Gy. PMID:25368490

  7. Mouse Bone Marrow-Derived Endothelial Progenitor Cells Do Not Restore Radiation-Induced Microvascular Damage

    PubMed Central

    Seemann, Ingar; te Poele, Johannes A. M.; Hoving, Saske; Stewart, Fiona A.

    2014-01-01

    Background. Radiotherapy is commonly used to treat breast and thoracic cancers but it also causes delayed microvascular damage and increases the risk of cardiac mortality. Endothelial cell proliferation and revascularization are crucial to restore microvasculature damage and maintain function of the irradiated heart. We have therefore examined the potential of bone marrow-derived endothelial progenitor cells (BM-derived EPCs) for restoration of radiation-induced microvascular damage. Material & Methods. 16?Gy was delivered to the heart of adult C57BL/6 mice. Mice were injected with BM-derived EPCs, obtained from Eng+/+ or Eng+/? mice, 16 weeks and 28 weeks after irradiation. Morphological damage was evaluated at 40 weeks in transplanted mice, relative to radiation only and age-matched controls. Results. Cardiac irradiation decreased microvascular density and increased endothelial damage in surviving capillaries (decrease alkaline phosphatase expression and increased von Willebrand factor). Microvascular damage was not diminished by treatment with BM-derived EPCs. However, BM-derived EPCs from both Eng+/+ and Eng+/? mice diminished radiation-induced collagen deposition. Conclusion. Treatment with BM-derived EPCs did not restore radiation-induced microvascular damage but it did inhibit fibrosis. Endoglin deficiency did not impair this process. PMID:25101181

  8. Spinacia oleracea Modulates Radiation-Induced Biochemical Changes in Mice Testis

    PubMed Central

    Sisodia, Rashmi; Yadav, Ritu K.; Sharma, K. V.; Bhatia, A. L.

    2008-01-01

    The present study is an attempt to investigate the radioprotective efficacy of spinach against radiation induced oxidative stress, since its leaves are rich in antioxidants like carotenoids (β-carotene, lutein and zeaxanthin) and high content of proteins, minerals, vitamin C. For the experimental study, healthy Swiss mice were selected from an inbred colony and divided into four groups. Group I (normal) it did not receive any treatment. Group II (drug treated) was orally supplemented with extract of spinach extract once daily at the dose of 1100 mg/kg for fifteen consecutive days. Group III (control) received distilled water orally equivalent to spinach extract for fifteen days than exposed to 5 Gy of gamma radiation. Group IV (experimental) was also administered orally with spinach extract for 15 consecutive days once daily. Thereafter, exposed to single dose of 5Gy of gamma radiation. After the exposure mice were than sacrificed at different autopsy intervals viz. 1, 3, 7, 15 and 30 days. Testis was removed for various biochemical estimations viz. LPO, protein, cholesterol and glycogen. Radiation induced augmentation in lipid peroxidation, glycogen and cholesterol values were significantly ameliorated by supplementation of SE extract, whereas radiation induced deficit in protein content could be elevated. This indicates that spinach extract pre - treatment renders protection against various biochemical changes in the mice testis to some extent if taken continuously which might be due to synergistic effect of antioxidant constituents present in the spinach. PMID:20046739

  9. A gene expression signature distinguishes normal tissues of sporadic and radiation-induced papillary thyroid carcinomas

    PubMed Central

    Dom, G; Tarabichi, M; Unger, K; Thomas, G; Oczko-Wojciechowska, M; Bogdanova, T; Jarzab, B; Dumont, J E; Detours, V; Maenhaut, C

    2012-01-01

    Background: Papillary thyroid cancer (PTC) incidence increased dramatically in children after the Chernobyl accident, providing a unique opportunity to investigate the molecular features of radiation-induced thyroid cancer. In contrast to the previous studies that included age-related confounding factors, we investigated mRNA expression in PTC and in the normal contralateral tissues of patients exposed and non-exposed to the Chernobyl fallout, using age- and ethnicity-matched non-irradiated cohorts. Methods: Forty-five patients were analysed by full-genome mRNA microarrays. Twenty-two patients have been exposed to the Chernobyl fallout; 23 others were age-matched and resident in the same regions of Ukraine, but were born after 1 March 1987, that is, were not exposed to 131I. Results: A gene expression signature of 793 probes corresponding to 403 genes that permitted differentiation between normal tissues from patients exposed and from those who were not exposed to radiation was identified. The differences were confirmed by quantitative RT-PCR. Many deregulated pathways in the exposed normal tissues are related to cell proliferation. Conclusion: Our results suggest that a higher proliferation rate in normal thyroid could be related to radiation-induced cancer either as a predisposition or as a consequence of radiation. The signature allows the identification of radiation-induced thyroid cancers. PMID:22828612

  10. The role of secretory granules in radiation-induced dysfunction of rat salivary glands

    SciTech Connect

    Peter, B.; Van Waarde, M.A.W.H.; Konings, A.W.T.; Vissink, A. |; `s-Gravenmade, E.J.

    1995-02-01

    To investigate the possible role of secretory granules in radiation-induced salivary gland dysfunction, rats were pretreated with isoproterenol (5 mg/kg intraperitoneally) to degranulate salivary gland acini. At maximal depletion, salivary glands were locally irradiated with a single dose of 15 Gy of X rays. Parotid and submandibular/sublingual saliva samples were collected before and 1-10 days after irradiation. The lag phase, flow rate, concentrations of potassium and sodium, and amylase secretion were determined. Sham-treated, isoproterenol-treated and irradiated animals provided reference data. In the parotid gland, but not in the submandibular gland, protection against radiation-induced changes in flow rate and composition of saliva occurred after pretreatment with isoproterenol. Combining morphological data from a previous study with data from the current study, it is suggested that improvement of parotid gland function is attributed predominantly to a proliferative stimulus on acinar cells by isoproterenol and not to its degranulation effect. After pretreatment with isoproterenol, an earlier expression of radiation-induced acinar cell damage leading to death was observed, followed by a faster tissue recovery. Thus the proliferative stimulus on acinar cells may accelerate the unmasking of latent lethal damage, resulting in the earlier replacement of dead cells by new, functionally intact cells. 33 refs., 2 figs.

  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. 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. PMID:23004920

  13. Advances in dosimetry and biological predictors of radiation-induced esophagitis

    PubMed Central

    Yu, Yang; Guan, Hui; Dong, Yuanli; Xing, Ligang; Li, Xiaolin

    2016-01-01

    Objective To summarize the research progress about the dosimetry and biological predictors of radiation-induced esophagitis. Methods We performed a systematic literature review addressing radiation esophagitis in the treatment of lung cancer published between January 2009 and May 2015 in the PubMed full-text database index systems. Results Twenty-eight eligible documents were included in the final analysis. Many clinical factors were related to the risk of radiation esophagitis, such as elder patients, concurrent chemoradiotherapy, and the intense radiotherapy regimen (hyperfractionated radiotherapy or stereotactic body radiotherapy). The parameters including Dmax, Dmean, V20, V30, V50, and V55 may be valuable in predicting the occurrence of radiation esophagitis in patients receiving concurrent chemoradiotherapy. Genetic variants in inflammation-related genes are also associated with radiation-induced toxicity. Conclusion Dosimetry and biological factors of radiation-induced esophagitis provide clinical information to decrease its occurrence and grade during radiotherapy. More prospective studies are warranted to confirm their prediction efficacy. PMID:26869804

  14. 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.

  15. Radiation-induced gliomas following radiotherapy for craniopharyngiomas: a case report and review of the literature.

    PubMed

    Enchev, Yavor; Ferdinandov, Dilian; Kounin, Georgi; Encheva, Elitsa; Bussarsky, Ventzeslav

    2009-09-01

    The aim of this study was to collect, describe and analyze the radiation-induced gliomas in craniopharyngioma patients reported in the literature up to date. Review of the relevant literature was performed. One personal illustrative case was added. Reports of 15 patients, including the presented illustrative case, were evaluated. The average age of the patients at the time of irradiation was 12.5 years. All patients underwent conventional fractionated radiotherapy with mean total radiation dose of 55Gy and an average latency period of 10.8 years. Glioma localization varied with the highest frequency of the temporal lobe involvement. All but one patient had high-grade gliomas on the histological exam. Although exceptionally rare, the radiation-induced gliomas in craniopharyngioma patients are potentially possible, long-term complications with devastating consequences in typically younger patients with long life-expectancy. The radiation-induced iatrogenic injury on one hand should provoke the research and elaboration of safer and at least, equally efficient alternative treatment modalities and on the other hand ought to prompt the investigation of the patients' risk factors predisposing the oncogenesis after irradiation. PMID:19447544

  16. The Efficacy of Nardostachys Jatamansi Against The Radiation Induced Haematological Damage In Rats

    PubMed Central

    Gowda, Damodara K M; Shetty, Lathika; A P, Krishna; Kumari, Suchetha N; Sanjeev, Ganesh; P, Naveen

    2013-01-01

    Introduction: Radiation is increasingly being used for medical purposes and it is an established weapon in the diagnosis and the therapy of cancer. An exposure to 1-2 Gys causes the NVD (Nausea, vomiting, diarrhoea) syndrome, whereas an exposure to 2-6 Gys causes the haematopoietic syndrome. The aim of the present study was to investigate the protective effect of the Nardostachys jatamansi root extract (NJE) on the radiation induced haematological damage in rats. Materials and Methods: EBR was performed at the Microtron Centre, Mangalore University, India. Rats were treated with NJE once daily for 15 days before and after the irradiation. After the irradiation, blood was collected for determining the peripheral blood counts (RBC and WBC), haemoglobin, the platelet count and the packed cell volume (PCV) at 6 hours, 12 hours, 24 hours, 48 hours and 5, 10 and 15 days post irradiation. The data was analyzed by one way ANOVA, followed by the Tukeys test for multiple comparisons. Result: NJE provided protection against the radiation induced haematological disorders. The rats treated with NJE exhibited a time dependent significant elevation in all the haematological parameters which were studied and its modulation upto the near normal level was recorded. Conclusion: From this study, we concluded that, NJE provides protection by modulating the radiation induced damage on the haematopoietic system. PMID:23905085

  17. 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 radiation induced bystander effects in vivo.

  18. Age-specific nomogram of brachial-ankle pulse wave velocity in Japanese adolescents.

    PubMed

    Miyai, Nobuyuki; Utsumi, Miyoko; Gowa, Yoshiaki; Igarashi, Yuko; Miyashita, Kazuhisa; Takeda, Shintaro; Arita, Mikio

    2013-01-01

    To obtain data on the brachial-ankle pulse wave velocity (baPWV) distribution during adolescence, a total of 3215 Japanese adolescents ranging from 12 to 18 years of age were studied. The brachial-ankle pulse wave velocity increased substantially with age and was significantly higher in males than in females. Multivariate regression analysis revealed that age, weight, and systolic and diastolic blood pressures were the major determinants of baPWV for both genders. Age-specific centile curves of baPWV were constructed for males and females by regression curve analysis. The proposed distribution curves of baPWV and its derived cutoff values may allow the atherosclerotic risk profile among adolescents of different ages to be more precisely estimated. PMID:22680041

  19. Percutaneous humeral derotational osteotomy in obstetrical brachial plexus palsy: a new technique.

    PubMed

    Aly, A; Bahm, J; Schuind, F

    2014-06-01

    Thirty three per cent of children with obstetrical brachial plexus palsy with incomplete neurological recovery develop shoulder internal contracture associated with osseous deformity. Some of the older children are treated by humeral derotational osteotomy. The classical technique of open approach to the humeral diaphysis and plate fixation imposes a longitudinal scar and carries significant risks (nonunion, nerve palsy); a secondary procedure for plate removal is necessary in a significant proportion of patients. The authors report a new technique of percutaneous humeral osteotomy with osteosynthesis by Hoffmann external fixator. In six cases bone healing was obtained at an average of 45 days, without adverse complication. The postoperative results showed improved shoulder function. This new technique is simple and safe; it represents a new option for the treatment of sequelae of obstetrical brachial plexus palsy. PMID:23748411

  20. Ultrasound-guided central cluster approach for the supraclavicular brachial plexus block: a case series

    PubMed Central

    Lee, Mi Geum; Lee, Kyung Cheon; Kim, Hong Soon; Park, Seol Ju; Suh, Young Je

    2015-01-01

    There are many different approaches to ultrasound-guided supraclavicular brachial plexus block (US-SCBPB), and each has a different success rate and complications. The most commonly performed US-SCBPB is the corner pocket approach in which the needle is advanced very close to the subclavian artery and pleura. Therefore, it may be associated with a risk of subclavian artery puncture or pneumothorax. We advanced the needle into the central part of the neural cluster after penetrating the sheath of the brachial plexus in US-SCBPB. We refer to this new method as the "central cluster approach." In this approach, the needle does not have to advance close to the subclavian artery or pleura. The aim of this study was to evaluate the clinical outcomes of the central cluster approach in US-SCBPB. PMID:26634085

  1. Perspectives on glenohumeral joint contractures and shoulder dysfunction in children with perinatal brachial plexus palsy.

    PubMed

    Gharbaoui, Idris S; Gogola, Gloria R; Aaron, Dorit H; Kozin, Scott H

    2015-01-01

    Shoulder joint deformities continue to be a challenging aspect of treating upper plexus lesions in children with perinatal brachial plexus palsy (PBPP). It is increasingly recognized that PBPP affects the glenohumeral joint specifically, and that abnormal scapulothoracic movements are a compensatory development. The pathophysiology and assessment of glenohumeral joint contractures, the progression of scapular dyskinesia and skeletal dysplasia, and current shoulder imaging techniques are reviewed. PMID:25835253

  2. Unusual brachial plexus lesion: Hematoma masquerading as a peripheral nerve sheath tumor

    PubMed Central

    Krisht, Khaled M.; Karsy, Michael; Shah, Lubdha M.; Schmidt, Meic H.; Dailey, Andrew T.

    2016-01-01

    Background: Malignant peripheral nerve sheath tumors (MPNSTs) of the brachial plexus have unique radiographic and clinical findings. Patients often present with progressive upper extremity paresthesias, weakness, and pain. On magnetic resonance (MR) imaging, lesions are isointense on T1-weighted and hyperintense on T2-weighted sequences, while also demonstrating marked enhancement on MR studies with gadolinium diethylenetriamine pentaacetic acid. On the basis of their characteristic MR imaging features and rapid clinical progression, two brachial plexus lesions proved to be organizing hematomas rather than MPNST. Methods: A 51-year-old male and a 31-year-old female were both assessed for persistent and worsened left-sided upper extremity pain, paresthesias, and weakness. In both cases, the MR imaging of the brachial plexus demonstrated an extraspinal enhancing lesion located within the left C7–T1 neuroforamina. Results: Although the clinical and radiographic MR features for these 2 patients were consistent with MPNSTs, both lesions proved to be benign organizing hematomas. Conclusions: These two case studies emphasize that brachial plexus hematomas may mimic MPNSTs on MR studies. Accurate diagnosis of these lesions is critical for determining the appropriate management options and treatment plans. Delaying the treatment of a highly aggressive nerve sheath tumor can have devastating consequences, whereas many hematomas resolve without surgery. Therefore, if the patient has stable findings on neurological examination and a history of trauma, surgical intervention may be delayed in favor of repeat MR imaging in 2–3 months to re-evaluate the size of the mass. PMID:26904368

  3. Sensory Evaluation of the Hands in Children with Brachial Plexus Birth Injury

    ERIC Educational Resources Information Center

    Palmgren, Tove; Peltonen, Jari; Linder, Tove; Rautakorpi, Sanna; Nietosvaara, Yrjana

    2007-01-01

    The aim of this study was to examine sensory changes of the hand in brachial plexus birth injury (BPBI). Ninety-five patients (43 females, 52 males) comprising two age groups, 6 to 8 years (mean age 7y 6mo) and 12 to 14 years (mean age 13y 2mo), were included. Sixty-four had upper (cervical [C] 5-6), 19 upper and middle (C5-7), and 12 had total…

  4. Effects of moisture exposure on radiation-induced MOS device degradation and its implications for long-term aging.

    SciTech Connect

    Dasgupta, A.; Lum, Gary K.; Zhou, X. J.; Francis, S. A.; Schrimpf, Ron D.; Fleetwood, Daniel M.; Schwank, James Ralph; Felix, James Andrew; Shaneyfelt, Marty Ray; Dodd, Paul Emerson; Pantelides, Sokrates T.

    2008-02-01

    Large and unexpected radiation-induced voltage shifts have been observed for some MOS technologies exposed to moisture. The mechanisms for these large voltage shifts and their implications for long-term aging are discussed.

  5. Rare case of radiation-induced trigeminal schwannoma occurring in a long-term glioblastoma multiforme survivor.

    PubMed

    Al Shalchi, Mina; Hussain, Shaila; Giridharan, Selvaraj; Albanese, Erminia

    2016-01-01

    Glioblastoma multiforme (GBM) is a high-grade primary brain tumour with a notably poor prognosis. Research demonstrates a median survival of just over 1 year following aggressive treatment. Long-term survival is notably rare. Cranial radiotherapy and postexcisional prophylactic treatment is associated with the development of second, histologically distinct tumours in rare cases. Radiation-induced intracranial schwannomas are uncommon, with only a small number of cranial nerve schwannoma cases reported in recent decades. To our knowledge, this is the first reported case of a radiation-induced benign trigeminal schwannoma occurring following long-term survival from glioblastoma. Here we present (1) a rare case of 14-year survival following treatment of a right parietal glioblastoma and the development of a radiation-induced benign trigeminal schwannoma in a 35-year-old man, and (2) a review of radiation-induced schwannoma cases reported in the existing literature. PMID:26969360

  6. 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

  7. 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.

  8. Surgical outcomes of the brachial plexus lesions caused by gunshot wounds in adults

    PubMed Central

    2009-01-01

    Background The management of brachial plexus injuries due to gunshot wounds is a surgical challenge. Better surgical strategies based on clinical and electrophysiological patterns are needed. The aim of this study is to clarify the factors which may influence the surgical technique and outcome of the brachial plexus lesions caused by gunshot injuries. Methods Two hundred and sixty five patients who had brachial plexus lesions caused by gunshot injuries were included in this study. All of them were male with a mean age of 22 years. Twenty-three patients were improved with conservative treatment while the others underwent surgical treatment. The patients were classified and managed according to the locations, clinical and electrophysiological findings, and coexisting lesions. Results The wounding agent was shrapnel in 106 patients and bullet in 159 patients. Surgical procedures were performed from 6 weeks to 10 months after the injury. The majority of the lesions were repaired within 4 months were improved successfully. Good results were obtained in upper trunk and lateral cord lesions. The outcome was satisfactory if the nerve was intact and only compressed by fibrosis or the nerve was in-contunuity with neuroma or fibrosis. Conclusion Appropriate surgical techniques help the recovery from the lesions, especially in patients with complete functional loss. Intraoperative nerve status and the type of surgery significantly affect the final clinical outcome of the patients. PMID:19627573

  9. Obstetric brachial plexus palsy: reviewing the literature comparing the results of primary versus secondary surgery.

    PubMed

    Socolovsky, Mariano; Costales, Javier Robla; Paez, Miguel Domnguez; Nizzo, Gustavo; Valbuena, Sebastian; Varone, Ernesto

    2016-03-01

    Obstetric brachial plexus injuries (OBPP) are a relatively common stretch injury of the brachial plexus that occurs during delivery. Roughly 30% of patients will not recover completely and will need a surgical repair. Two main treatment strategies have been used: primary surgery, consisting in exploring and reconstructing the affected portions of the brachial plexus within the first few months of the patient's life, and secondary procedures that include tendon or muscle transfers, osteotomies, and other orthopedic techniques. Secondary procedures can be done as the only surgical treatment of OBPP or after primary surgery, in order to minimize any residual deficits. Two things are crucial to achieving a good outcome: (1) the appropriate selection of patients, to separate those who will spontaneously recover from those who will recover only partially or not at all; and (2) a good surgical technique. The objective of the present review is to assess the published literature concerning certain controversial issues in OBPP, especially in terms of the true current state of primary and secondary procedures, their results, and the respective roles each plays in modern-day treatment of this complex pathology. Considerable published evidence compiled over decades of surgical experience favors primary nerve surgery as the initial therapeutic step in patients who do not recover spontaneously, followed by secondary surgeries for further functional improvement. As described in this review, the results of such treatment can greatly ameliorate function in affected limbs. For best results, multi-disciplinary teams should treat these patients. PMID:26615411

  10. Selective ultrasound guided pectoral nerve targeting in breast augmentation: How to spare the brachial plexus cords?

    PubMed

    Desroches, Jean; Grabs, Ursula; Grabs, Detlev

    2013-01-01

    Subpectoral breast augmentation surgery under regional anesthesia requires the selective neural blockade of the medial and lateral pectoral nerves to diminish postoperative pain syndromes. The purpose of this cadaver study is to demonstrate a reliable ultrasound guided approach to selectively target the pectoral nerves and their branches while sparing the brachial plexus cords. After evaluating the position and appearance of the pectoral nerves in 25 cadavers (50 sides), a portable ultrasound machine was used to guide the injection of 10 ml of 0.2% aqueous methylene blue solution in the pectoral region on both sides of three Thiel's embalmed cadavers using a single entry point-triple injection technique. This technique uses a medial to lateral approach with the entry point just medial to the pectoral minor muscle and three subsequent infiltrations: (1) deep lateral part of the pectoralis minor muscle, (2) between the pectoralis minor and major muscles, and (3) between the pectoralis major muscle and its posterior fascia under ultrasound visualization. Dissection demonstrates that the medial and lateral pectoral nerves were well stained while leaving the brachial plexus cords unstained. We show that 10 ml of an injected solution is sufficient to stain all the medial and lateral pectoral nerve branches without a proximal extension to the cords of the brachial plexus. PMID:22730005

  11. Regional compliance of brachial artery and saline infusion in patients with arteriosclerosis obliterans.

    PubMed

    Levenson, J A; Simon, A C; Maarek, B E; Gitelman, R J; Fiessinger, J N; Safar, M E

    1985-01-01

    Simultaneous brachial artery pressure and blood flow measurements were made in 15 patients with arteriosclerosis of the lower limbs (AOLL) and in controls of the same age and sex. Blood flow was evaluated by a pulsed Doppler device with a double-transducer probe. From analysis of the pressure-flow curves during diastole, regional arterial compliance (RAC) was determined by using as a model of the forearm arterial tree a system of tubes, each with a storage capacity, in series with the arteriolar resistance vessels. In AOLL patients, RAC was significantly reduced (102 +/- 13 vs 173 +/- 14.10(-4) ml/mm Hg, p less than 0.01), and systolic pressure was significantly increased. After saline infusion, systolic pressure continued to increase and arterial compliance, to decrease; brachial blood flow did not change. Study of the baroreflex sensitivity in AOLL patients under basal conditions indicated that a higher pulse pressure was required to obtain the same heart rate as in the controls. The study provided evidence that in AOLL patients: 1) compliance was reduced in the brachial artery (a regional circulation with no clinical evidence of arterial occlusion); 2) an increase in systolic pressure resulted from the decreased arterial compliance; and 3) saline infusion exaggerated the observed reduction in arterial compliance and increase in systolic pressure. PMID:3966910

  12. Does retraction of the sternum during median sternotomy result in brachial plexus injuries?

    PubMed

    Healey, Scott; O'Neill, Bridie; Bilal, Haris; Waterworth, Paul

    2013-07-01

    A best evidence topic in cardiac surgery was written according to a structured protocol. The question addressed was 'does retraction of the sternum during median sternotomy result in brachial plexus injuries or peripheral neuropathies?' Altogether 58 papers were found using the reported search, of which 12 represented the best evidence to answer the question. The authors, date, journal and country of publication, patient group studied, study type, relevant outcomes and results of these papers were tabulated. Caudal placement of the retractor or relieving the pressure superiorly by removing the upper blades of a retractor (P = 0.02) and use of a caudally placed symmetrical retractor has been shown to reduce neuropathy. Positioning of the patient with 'hands up' positioning showed significant reduction in the incidence of brachial plexus injuries. Furthermore, how wide the retractor is opened and use of an asymmetrical retractor for internal mammary artery (IMA) harvesting are also important factors in quantifying risk of postoperative neuropathy. Wider sternal retraction and longer bypass time did increase the risk of developing postoperative neuropathy. Three asymmetrical retractors were looked at that demonstrates the Delacroix-Chevalier to be the safest (P < 0.05). We conclude that median sternotomy risks brachial plexus injury and where possible the sternum should be opened as small a distance as possible with symmetrical retractor and using a caudally placed retractor. PMID:23513004

  13. Triangle Tilt Surgery in an Older Pediatric Patient With Obstetric Brachial Plexus Injury

    PubMed Central

    Nath, Rahul K.; Amrani, Abdelouahed; Melcher, Sonya E.; Eichhorn, Mitchell G.

    2009-01-01

    Children with an obstetric brachial plexus injury have an elevated risk of long-term impairment if they do not fully recover by the age of 3 months. Persistent nerve damage leads to muscle abnormalities and progressive muscle and bone deformities. Several procedures have been described to treat this severe deformity. We have demonstrated the benefits of the triangle tilt procedure in young children with a mean age of 6.4 years (2.2 to 10.3), yet the treatment of humeral head subluxation secondary to obstetric brachial plexus injury represents a challenge in older pediatric patients. This case report demonstrates the effectiveness of triangle tilt surgery for the treatment of glenohumeral joint deformity in a 12 year old pediatric patient with left sided residual brachial plexus injury. The patient in this study showed noticeable clinical improvements, an improvement in glenohumeral joint dysplasia, and a reduction in humeral head subluxation 2 years after triangle tilt surgery. There was functional improvement 25 months after surgery. The patient's total Mallet score for shoulder function improved from 14 to 20 (of 25). In this case report, we demonstrate that the triangle tilt procedure can be used for older pediatric patients without modification. This observation has provided valuable information and is, to our knowledge, the first documented improvement of a glenohumeral joint deformity in an older pediatric patient. Future studies will be needed to determine the long-term success of triangle tilt surgery in this age group. PMID:19641599

  14. Gross anatomy of the brachial plexus in the giant Anteater (Myrmecophaga tridactyla).

    PubMed

    Souza, P R; Cardoso, J R; Araujo, L B M; Moreira, P C; Cruz, V S; Araujo, E G

    2014-10-01

    Ten forelimbs of five Myrmecophaga tridactyla were examined to study the anatomy of the brachial plexus. The brachial plexuses of the M. tridactyla observed in the present study were formed by the ventral rami of the last four cervical spinal nerves, C5 through C8, and the first thoracic spinal nerve, T1. These primary roots joined to form two trunks: a cranial trunk comprising ventral rami from C5-C7 and a caudal trunk receiving ventral rami from C8-T1. The nerves originated from these trunks and their most constant arrangement were as follows: suprascapular (C5-C7), subscapular (C5-C7), cranial pectoral (C5-C8), caudal pectoral (C8-T1), axillary (C5-C7), musculocutaneous (C5-C7), radial (C5-T1), median (C5-T1), ulnar (C5-T1), thoracodorsal (C5-C8), lateral thoracic (C7-T1) and long thoracic (C6-C7). In general, the brachial plexus in the M. tridactyla is similar to the plexuses in mammals, but the number of rami contributing to the formation of each nerve in the M. tridactyla was found to be larger than those of most mammals. This feature may be related to the very distinctive anatomical specializations of the forelimb of the anteaters. PMID:23952693

  15. Brachial artery pseudoaneurysm arising from the stump of a ligated arteriovenous fistula.

    PubMed

    Cox, Nicola; Sahnan, Kapil; Yee, Chris Pui Yan; Sritharan, Kaji

    2015-01-01

    An 85-year-old man presented to A&E department with a bleeding, pulsatile mass within the left antecubital fossa. He reported a 3-month history of an increasing, painless swelling. He had a history of end-stage renal failure secondary to antiglomerular basement membrane disease. 14 years prior, he had a left brachiocephalic fistula created, which was ligated shortly after its creation due to Steal syndrome. Examination revealed a 10×15×10 cm pulsatile, non-tender mass with overlying ulceration in the left antecubital fossa. Arterial duplex demonstrated a pseudoaneurysm arising from the left distal brachial artery with a 9 mm neck. The patient underwent surgical exploration and repair. At surgery, a large brachial artery pseudoaneurysm at the site of the previous fistula ligation was found. The overlying ulcerated skin and pseudoaneurysm were excised en mass, and the arterial defect repaired by transection and end-to-end anastomosis. This is the first reported case of a brachial artery pseudoaneurysm occurring following arteriovenous fistula ligation. PMID:26063109

  16. 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.

  17. 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. PMID:24137346

  18. Regulation of ionizing radiation-induced apoptosis by a manganese porphyrin complex

    SciTech Connect

    Lee, Jin Hyup; Lee, You Mie; Park, Jeen-Woo . E-mail: parkjw@knu.ac.kr

    2005-08-26

    Ionizing radiation induces the production of reactive oxygen species, which play an important causative role in apoptotic cell death. Therefore, compounds that scavenge reactive oxygen species may confer regulatory effects on apoptosis. Superoxide dismutase (SOD) mimetics have been shown to be protective against cell injury caused by reactive oxygen species. We investigated the effects of the manganese (III) tetrakis(N-methyl-2-pyridyl)porphyrin (MnTMPyP), a cell-permeable SOD mimetic, on ionizing radiation-induced apoptosis. Upon exposure to 2 Gy of {gamma}-irradiation, there was a distinct difference between the control cells and the cells pre-treated with 5 {mu}M MnTMPyP for 2 h with regard to apoptotic parameters, cellular redox status, mitochondria function, and oxidative damage to cells. MnTMPyP effectively suppressed morphological evidence of apoptosis and DNA fragmentation in U937 cells exposed to ionizing radiation. The [GSSG]/[GSH + GSSG] ratio and the generation of intracellular reactive oxygen species were higher and the [NADPH]/[NADP{sup +} + NADPH] ratio was lower in control cells compared to MnTMPyP-treated cells. The ionizing radiation-induced mitochondrial damage reflected by the altered mitochondrial permeability transition, the increase in the accumulation of reactive oxygen species, and the reduction of ATP production were significantly higher in control cells compared to MnTMPyP-treated cells. MnTMPyP pre-treated cells showed significant inhibition of apoptotic features such as activation of caspase-3, up-regulation of Bax and p53, and down-regulation of Bcl-2 compared to control cells upon exposure to ionizing radiation. This study indicates that MnTMPyP may play an important role in regulating the apoptosis induced by ionizing radiation presumably through scavenging of reactive oxygen species.

  19. 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.

  20. Stem Cell Therapies for the Treatment of Radiation-Induced Normal Tissue Side Effects

    PubMed Central

    Benderitter, Marc; Caviggioli, Fabio; Chapel, Alain; Coppes, Robert P.; Guha, Chandan; Klinger, Marco; Malard, Olivier; Stewart, Fiona; Tamarat, Radia; Luijk, Peter Van

    2014-01-01

    Abstract Significance: Targeted irradiation is an effective cancer therapy but damage inflicted to normal tissues surrounding the tumor may cause severe complications. While certain pharmacologic strategies can temper the adverse effects of irradiation, stem cell therapies provide unique opportunities for restoring functionality to the irradiated tissue bed. Recent Advances: Preclinical studies presented in this review provide encouraging proof of concept regarding the therapeutic potential of stem cells for treating the adverse side effects associated with radiotherapy in different organs. Early-stage clinical data for radiation-induced lung, bone, and skin complications are promising and highlight the importance of selecting the appropriate stem cell type to stimulate tissue regeneration. Critical Issues: While therapeutic efficacy has been demonstrated in a variety of animal models and human trials, a range of additional concerns regarding stem cell transplantation for ameliorating radiation-induced normal tissue sequelae remain. Safety issues regarding teratoma formation, disease progression, and genomic stability along with technical issues impacting disease targeting, immunorejection, and clinical scale-up are factors bearing on the eventual translation of stem cell therapies into routine clinical practice. Future Directions: Follow-up studies will need to identify the best possible stem cell types for the treatment of early and late radiation-induced normal tissue injury. Additional work should seek to optimize cellular dosing regimes, identify the best routes of administration, elucidate optimal transplantation windows for introducing cells into more receptive host tissues, and improve immune tolerance for longer-term engrafted cell survival into the irradiated microenvironment. Antioxid. Redox Signal. 21: 338–355. PMID:24147585

  1. Smad, but not MAPK, pathway mediates the expression of type I collagen in radiation induced fibrosis

    SciTech Connect

    Yano, Hiroyuki; Division of Radioisotope Research, Department of Research Support, Research Promotion Project, Oita University, 1-1 Idaigaoka Hasama-machi, Yufu, Oita 879-5593 ; Hamanaka, Ryoji; 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.

  2. Targeted Overexpression of Mitochondrial Catalase Prevents Radiation-Induced Cognitive Dysfunction

    PubMed Central

    Parihar, Vipan K.; Allen, Barrett D.; Tran, Katherine K.; Chmielewski, Nicole N.; Craver, Brianna M.; Martirosian, Vahan; Morganti, Josh M.; Rosi, Susanna; Vlkolinsky, Roman; Acharya, Munjal M.; Nelson, Gregory A.; Allen, Antiño R.

    2015-01-01

    Abstract Aims: Radiation-induced disruption of mitochondrial function can elevate oxidative stress and contribute to the metabolic perturbations believed to compromise the functionality of the central nervous system. To clarify the role of mitochondrial oxidative stress in mediating the adverse effects of radiation in the brain, we analyzed transgenic (mitochondrial catalase [MCAT]) mice that overexpress human catalase localized to the mitochondria. Results: Compared with wild-type (WT) controls, overexpression of the MCAT transgene significantly decreased cognitive dysfunction after proton irradiation. Significant improvements in behavioral performance found on novel object recognition and object recognition in place tasks were associated with a preservation of neuronal morphology. While the architecture of hippocampal CA1 neurons was significantly compromised in irradiated WT mice, the same neurons in MCAT mice did not exhibit extensive and significant radiation-induced reductions in dendritic complexity. Irradiated neurons from MCAT mice maintained dendritic branching and length compared with WT mice. Protected neuronal morphology in irradiated MCAT mice was also associated with a stabilization of radiation-induced variations in long-term potentiation. Stabilized synaptic activity in MCAT mice coincided with an altered composition of the synaptic AMPA receptor subunits GluR1/2. Innovation: Our findings provide the first evidence that neurocognitive sequelae associated with radiation exposure can be reduced by overexpression of MCAT, operating through a mechanism involving the preservation of neuronal morphology. Conclusion: Our article documents the neuroprotective properties of reducing mitochondrial reactive oxygen species through the targeted overexpression of catalase and how this ameliorates the adverse effects of proton irradiation in the brain. Antioxid. Redox Signal. 22, 78–91. PMID:24949841

  3. Radiation-induced brain injury: low-hanging fruit for neuroregeneration.

    PubMed

    Burns, Terry C; Awad, Ahmed J; Li, Matthew D; Grant, Gerald A

    2016-05-01

    Brain radiation is a fundamental tool in neurooncology to improve local tumor control, but it leads to profound and progressive impairments in cognitive function. Increased attention to quality of life in neurooncology has accelerated efforts to understand and ameliorate radiation-induced cognitive sequelae. Such progress has coincided with a new understanding of the role of CNS progenitor cell populations in normal cognition and in their potential utility for the treatment of neurological diseases. The irradiated brain exhibits a host of biochemical and cellular derangements, including loss of endogenous neurogenesis, demyelination, and ablation of endogenous oligodendrocyte progenitor cells. These changes, in combination with a state of chronic neuroinflammation, underlie impairments in memory, attention, executive function, and acquisition of motor and language skills. Animal models of radiation-induced brain injury have demonstrated a robust capacity of both neural stem cells and oligodendrocyte progenitor cells to restore cognitive function after brain irradiation, likely through a combination of cell replacement and trophic effects. Oligodendrocyte progenitor cells exhibit a remarkable capacity to migrate, integrate, and functionally remyelinate damaged white matter tracts in a variety of preclinical models. The authors here critically address the opportunities and challenges in translating regenerative cell therapies from rodents to humans. Although valiant attempts to translate neuroprotective therapies in recent decades have almost uniformly failed, the authors make the case that harnessing human radiation-induced brain injury as a scientific tool represents a unique opportunity to both successfully translate a neuroregenerative therapy and to acquire tools to facilitate future restorative therapies for human traumatic and degenerative diseases of the central nervous system. PMID:27132524

  4. Protection from radiation-induced mitochondrial and genomic DNA damage by an extract of Hippophae rhamnoides.

    PubMed

    Shukla, Sandeep Kumar; Chaudhary, Pankaj; Kumar, Indracanti Prem; Samanta, Namita; Afrin, Farhat; Gupta, Manju Lata; Sharma, Upendra Kumar; Sinha, Arun Kumar; Sharma, Yogendra Kumar; Sharma, Rakesh Kumar

    2006-12-01

    Hippophae rhamnoides or seabuckthorn is used extensively in Indian and Tibetan traditional medicine for the treatment of circulatory disorders, ischemic heart disease, hepatic injury, and neoplasia. In the present study, we have evaluated the radioprotective potential of REC-1001, a fraction isolated from the berries of H. rhamnoides. Chemical analysis of the extract indicated that REC-1001 was approximately 68% by weight polyphenols, and contained kaempferol, isorhamnetin, and quercetin. The effect of REC-1001 on modulating radiation-induced DNA damage was determined in murine thymocytes by measuring nonspecific nuclear DNA damage at the whole genome level using the alkaline halo assay and by measuring sequence/gene-specific DNA damage both in nuclear DNA (beta-globin gene) and in mitochondrial DNA using a quantitative polymerase chain reaction. Treatment with 10 Gy resulted in a significant amount of DNA damage in the halo assay and reductions in the amplification of both the beta-globin gene and mitochondrial DNA. REC-1001 dose-dependently reduced the amount of damage detected in each assay, with the maximum protective effects observed at the highest REC-1001 dose evaluated (250 micro g/ml). Studies measuring the nicking of naked plasmid DNA further established the radioprotective effect of REC-1001. To elucidate possible mechanisms of action, the antioxidant properties and the free-radical scavenging activities of REC-1001 were evaluated. REC-1001 dose-dependently scavenged radiation-induced hydroxyl radicals, chemically-generated superoxide anions, stabilized DPPH radicals, and reduced Fe(3+) to Fe(2+). The results of the study indicate that the REC-1001 extract of H. rhamnoides protects mitochondrial and genomic DNA from radiation-induced damage. The polyphenols/flavonoids present in the extract might be responsible for the free radical scavenging and DNA protection afforded by REC-1001. PMID:16948057

  5. 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.

  6. Proteomic overview and perspectives of the radiation-induced bystander effects.

    PubMed

    Chevalier, François; Hamdi, Dounia Houria; Saintigny, Yannick; Lefaix, Jean-Louis

    2015-01-01

    Radiation proteomics is a recent, promising and powerful tool to identify protein markers of direct and indirect consequences of ionizing radiation. The main challenges of modern radiobiology is to predict radio-sensitivity of patients and radio-resistance of tumor to be treated, but considerable evidences are now available regarding the significance of a bystander effect at low and high doses. This "radiation-induced bystander effect" (RIBE) is defined as the biological responses of non-irradiated cells that received signals from neighboring irradiated cells. Such intercellular signal is no more considered as a minor side-effect of radiotherapy in surrounding healthy tissue and its occurrence should be considered in adapting radiotherapy protocols, to limit the risk for radiation-induced secondary cancer. There is no consensus on a precise designation of RIBE, which involves a number of distinct signal-mediated effects within or outside the irradiated volume. Indeed, several cellular mechanisms were proposed, including the secretion of soluble factors by irradiated cells in the extracellular matrix, or the direct communication between irradiated and neighboring non-irradiated cells via gap junctions. This phenomenon is observed in a context of major local inflammation, linked with a global imbalance of oxidative metabolism which makes its analysis challenging using in vitro model systems. In this review article, the authors first define the radiation-induced bystander effect as a function of radiation type, in vitro analysis protocols, and cell type. In a second time, the authors present the current status of protein biomarkers and proteomic-based findings and discuss the capacities, limits and perspectives of such global approaches to explore these complex intercellular mechanisms. PMID:25795126

  7. Role of ferulic acid in the amelioration of ionizing radiation induced inflammation: a murine model.

    PubMed

    Das, Ujjal; Manna, Krishnendu; Sinha, Mahuya; Datta, Sanjukta; Das, Dipesh Kr; Chakraborty, Anindita; Ghosh, Mahua; Saha, Krishna Das; Dey, Sanjit

    2014-01-01

    Ionizing radiation is responsible for oxidative stress by generating reactive oxygen species (ROS), which alters the cellular redox potential. This change activates several redox sensitive enzymes which are crucial in activating signaling pathways at molecular level and can lead to oxidative stress induced inflammation. Therefore, the present study was intended to assess the anti-inflammatory role of ferulic acid (FA), a plant flavonoid, against radiation-induced oxidative stress with a novel mechanistic viewpoint. FA was administered (50 mg/kg body wt) to Swiss albino mice for five consecutive days prior to exposing them to a single dose of 10 Gy 60Co γ-irradiation. The dose of FA was optimized from the survival experiment and 50 mg/kg body wt dose showed optimum effect. FA significantly ameliorated the radiation induced inflammatory response such as phosphorylation of IKKα/β and IκBα and consequent nuclear translocation of nuclear factor kappa B (NF-κB). FA also prevented the increase of cycloxygenase-2 (Cox-2) protein, inducible nitric oxide synthase-2 (iNOS-2) gene expression, lipid peroxidation in liver and the increase of tumor necrosis factor-alpha (TNF-α) and interleukin-6 (IL-6) in serum. It was observed that exposure to radiation results in decreased activity of superoxide dismutase (SOD), catalase (CAT) and the pool of reduced glutathione (GSH) content. However, FA treatment prior to irradiation increased the activities of the same endogenous antioxidants. Thus, pretreatment with FA offers protection against gamma radiation induced inflammation. PMID:24854039

  8. Cancer predispostion, radiosensitivity and the risk of radiation-induced cancers. I. Background

    SciTech Connect

    Sankaranarayanan, K.; Chakraborty, R. |

    1995-08-01

    This paper presents an overview of current knowledge on genetic predisposition to cancer and on enhanced sensitivity of cancer-predisposed genotypes to cancers induced by ionizing radiation. It is intended to provide a background and set the stage for the next papers in this series in which we will assess how such heterogeneity in a population may affect estimates of the risk of radiation-induced cancers. The main findings of the present paper are the following: (1) {open_quotes}Cancer-predisposing genes{close_quotes} (i.e. those at which germinal mutations predispose to cancer) are present in the human genome; these genes are responsible not only for the rare familial cancer syndromes but also for a proportion of the common cancers. At least 21 such genes have now been cloned (including 9 tumor suppressor genes, 11 DNA repair genes and 1 proto-oncogene); further, at least 8 putative tumor suppressor genes and a gene involved in ataxia telangiectasia have been localized to specific chromosomes. (2) These genes play crucial roles in the control of cellular proliferation, programmed cell death (apoptosis) and/or one or another DNA repair pathway. Consequently, mutations in these genes are likely to {open_quotes}liberate{close_quotes} the cells from the normal constraints imposed by them, resulting in unconstrained growth characteristic of cancer. (3) At present, the evidence for increased sensitivity of cancer-predisposed genotypes to radiation-induced cancers is limited. However, current knowledge of the known functions of the cancer-predisposing genes and of the consequences of mutations in these provide (a) sufficient grounds for assuming that the genotypes of those predisposed to cancer may be at an increased risk for radiation-induced cancers and (b) the rationale for attempts to estimate quantitatively the impact of genotype-dependent differences in cancer predisposition and radiosensitivity on cancer risks in an irradiated population. 202 refs., 4 tabs.

  9. [gamma]-radiation-induced changes in the chemical and physical structure of poly(ethylene terephthalate)

    SciTech Connect

    Jin, Ho-Seon.

    1992-01-01

    Poly(ethylene terephthalate) (PET) film was irradiated with [gamma]-rays in air at doses from 0 to 620 Mrad, and at the rate of 0l8 to 1.0 Mrad/hr. Radiation-induced physical structure changes were studied by DMA and DSC measurements. Tensile properties were measured to find interrelationships with chemical and physical structure changes. Below 100 Mrad, PET shows little change in NMR and IR spectra. Fluorescence emission spectra, however, show the presence and increase of monohydroxy-substituted phenylene groups. This hydroxylation appears to stabilize the polymer. The phenylene group in PET also contributes to radiation-resistance. The amorphous-crystalline interfaces impede the penetration of oxygen and slow the oxidative chain scission. Between 100 and 215 Mrad, UV studies reveal that the rates of reaction begin to change rapidly. Chain scission appears to take place first in the interspherulitic amorphous regions and then in the intraspherulitic (interlamella) regions. [gamma]-Radiation-induced oxidative degradation shows aspects of both photolysis and of thermooxidative degradation (proton and carbon-13 NMR, and IR studies). It was concluded that the crystalline phase breaks down in to smaller crystallites, and these smaller crystallites grow in size by acting as nucleating sites. Tensile measurements show that throughout the range of irradiation studied the tensile strength at break and the percent elongation decrease. The tensile strength decreases uniformly and the percent elongation exhibits a more rapid decrease above 100 Mrad. The results of this study lead to the conclusion that [gamma]-radiation-induced oxidative degradation of PET involves products that are seen in both photolysis and thermooxidation.

  10. 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.

  11. Dosimetric Predictors of Radiation-induced Acute Nausea and Vomiting in IMRT for Nasopharyngeal Cancer

    SciTech Connect

    Lee, Victor H.F.; Ng, Sherry C.Y.; Leung, T.W.; Au, Gordon K.H.; Kwong, Dora L.W.

    2012-09-01

    Purpose: We wanted to investigate dosimetric parameters that would predict radiation-induced acute nausea and vomiting in intensity-modulated radiation therapy (IMRT) for undifferentiated carcinoma of the nasopharynx (NPC). Methods and Materials: Forty-nine consecutive patients with newly diagnosed NPC were treated with IMRT alone in this prospective study. Patients receiving any form of chemotherapy were excluded. The dorsal vagal complex (DVC) as well as the left and right vestibules (VB-L and VB-R, respectively) were contoured on planning computed tomography images. A structure combining both the VB-L and the VB-R, named VB-T, was also generated. All structures were labeled organs at risk (OAR). A 3-mm three-dimensional margin was added to these structures and labeled DVC+3 mm, VB-L+3 mm, VB-R+3 mm, and VB-T+3 mm to account for physiological body motion and setup error. No weightings were given to these structures during optimization in treatment planning. Dosimetric parameters were recorded from dose-volume histograms. Statistical analysis of parameters' association with nausea and vomiting was performed using univariate and multivariate logistic regression. Results: Six patients (12.2%) reported Grade 1 nausea, and 8 patients (16.3%) reported Grade 2 nausea. Also, 4 patients (8.2%) complained of Grade 1 vomiting, and 4 patients (8.2%) experienced Grade 2 vomiting. No patients developed protracted nausea and vomiting after completion of IMRT. For radiation-induced acute nausea, V40 (percentage volume receiving at least 40Gy) to the VB-T and V40>=80% to the VB-T were predictors, using univariate analysis. On multivariate analysis, V40>=80% to the VB-T was the only predictor. There were no predictors of radiation-induced acute vomiting, as the number of events was too small for analysis. Conclusions: This is the first study demonstrating that a V40 to the VB-T is predictive of radiation-induced acute nausea. The vestibules should be labeled as sensitive OARs, and weightings should be considered for dose sparing during optimization in the treatment planning of IMRT.

  12. Radiation-induced electron paramagnetic resonance signal and soybean isoflavones content

    NASA Astrophysics Data System (ADS)

    de Oliveira, Marcos R. R.; Mandarino, José M. G.; del Mastro, Nelida L.

    2012-09-01

    Electron Paramagnetic Resonance (EPR) is a well-known spectroscopic technique that detects paramagnetic centers and can detect free radicals with high sensitivity. In food, free radicals can be generated by several commonly used industrial processes, such as radiosterilization or heat treatment. EPR spectroscopy is used to detect radioinduced free radicals in food. In this work the relation between EPR signal induced by gamma irradiation treatment and soybean isoflavones content was investigated. Present results did not show correlation between total isoflavones content and the EPR signal. Nevertheless, some isoflavone contents had a negative correlation with the radiation-induced EPR signal.

  13. Study of the effect of dose-rate on radiation-induced damage to human erythrocytes

    NASA Astrophysics Data System (ADS)

    Krokosz, Anita; Koziczak, Renata; Gonciarz, Marta; Szweda-Lewandowska, Zofia

    2006-01-01

    Human erythrocytes suspended in an isotonic Na-phosphate buffer, pH 7.4 (hematocrit of 2%) were irradiated with γ-rays at three dose-rates of 66.7, 36.7, 25 Gy min -1 in order to investigate the influence of the dose-rate on radiation-induced membrane damage, hemoglobin oxidation and loss of reduced glutathione. The obtained results showed that such processes as erythrocyte hemolysis, lipid and protein destruction depend on the radiation dose-rate. The parameter values describing these processes showed an inverse dose-rate effect.

  14. Radiation-induced modification of the dry vacuum photoresist layers during ion implantation

    NASA Astrophysics Data System (ADS)

    Kotov, E. V.; Gudimenko, Yurii I.; Agabekov, Vladimir E.

    1992-08-01

    Peculiarities of 30...100 keV P+ and Ar+ ion implantation into dry vacuum resist on the base of -pyrone have been studied by x-ray photoelectron spectroscopy and Rutherford backscattering spectrometry. Phosphorus atom distribution profile has been shown to have an anomalous shape with two peaks, one of which is situated in a region of projected range, while the other is on the sample surface directly. Radiation-induced diffusion and solid phase reactions leading to phosphorus organic coating formation of about 40..50 Ao in thickness has been revealed to occur during phosphorus ion implantation.

  15. Remote sensor response study in the regime of the microwave radiation-induced magnetoresistance oscillations

    SciTech Connect

    Ye, Tianyu; Mani, R. G.; Wegscheider, W.

    2013-11-04

    A concurrent remote sensing and magneto-transport study of the microwave excited two dimensional electron system (2DES) at liquid helium temperatures has been carried out using a carbon detector to remotely sense the microwave activity of the 2D electron system in the GaAs/AlGaAs heterostructure during conventional magneto-transport measurements. Various correlations are observed and reported between the oscillatory magnetotransport and the remotely sensed reflection. In addition, the oscillatory remotely sensed signal is shown to exhibit a power law type variation in its amplitude, similar to the radiation-induced magnetoresistance oscillations.

  16. 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.

  17. 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.

  18. 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.

  19. 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 been shown to be activated in cells exposed to radiation from photons (like cell cycle arrest in G1/S), and that supplementation with SeM abolishes HZE particle-induced differential expression of many genes. Understanding the roles that these genes play in the radiation-induced transformation of cells may help to decipher the origins of radiation-induced cancer. PMID:17265150

  20. Immobilization of yeast cells on hydrogel carriers obtained by radiation-induced polymerization

    NASA Astrophysics Data System (ADS)

    Xin, Lu Zhao; Carenza, Mario; Kaetsu, Isao; Kumakura, Minoru; Yoshida, Masaru; Fujimura, Takashi

    Polymer hydrogels were obtained by radiation-induced copolymerization at -78°C of aqueous solutions of acrylic and methacrylic esters. The matrices were characterized by equilibrium water content measurements, by optical microscopy observations and by scanning electron microscopy analysis. Yeast cells were immobilized on these hydrogels and the ethanol productivity by batch fermentation was determined. Matrix hydrophilicity and porosity were found to deeply influence the adhesion of yeast cells and, hence, the ethanol productivity. The latter as well as other physico-chemical properties were also affected by the presence of a crosslinking agent added in small amounts to the polymerizing mixture.

  1. Transient radiation-induced absorption in materials for the DOI laser

    SciTech Connect

    Brannon, P.J.

    1995-01-01

    This is the final report on a series of experiments concerned with transient radiation-induced absorption in materials for a Cr,Nd:GSGG laser. Both the Sandia National Laboratories SPR III pulsed reactor and the Hermes III pulsed X-ray machine are used as radiation sources. The time dependence and the magnitude of the induced absorption in filter glasses and in doped and undoped LiNbO{sub 3} Q-switch materials have been measured. Gain has been observed in Cr,Nd:GSGG, the laser medium, when it is irradiated by X-rays.

  2. Radiation-induced changes in electrical conductivity of a wide range of copper alloys

    SciTech Connect

    Garner, F.A. ); Anderson, K.R. ); Shikama, T. )

    1991-01-01

    A wide variety of radiation-induced changes in electrical conductivity was observed in a series of irradiation experiments conducted on copper alloys in FFTF/MOTA. The behavior of each alloy was found to depend on the alloy composition, starting state, irradiation temperature, and the sometimes complex interaction of three radiation-driven processes. These processes are transmutation, void swelling, and solute redistribution. The objective of this effort is to identify those copper alloys that offer promise as high heat flux materials for fusion application. 13 refs., 4 figs., 2 tabs.

  3. Accurate quantitative measurements of brachial artery cross-sectional vascular area and vascular volume elastic modulus using automated oscillometric measurements: comparison with brachial artery ultrasound

    PubMed Central

    Tomiyama, Yuuki; Yoshinaga, Keiichiro; Fujii, Satoshi; Ochi, Noriki; Inoue, Mamiko; Nishida, Mutumi; Aziki, Kumi; Horie, Tatsunori; Katoh, Chietsugu; Tamaki, Nagara

    2015-01-01

    Increasing vascular diameter and attenuated vascular elasticity may be reliable markers for atherosclerotic risk assessment. However, previous measurements have been complex, operator-dependent or invasive. Recently, we developed a new automated oscillometric method to measure a brachial artery's estimated area (eA) and volume elastic modulus (VE). The aim of this study was to investigate the reliability of new automated oscillometric measurement of eA and VE. Rest eA and VE were measured using the recently developed automated detector with the oscillometric method. eA was estimated using pressure/volume curves and VE was defined as follows (VE=Δ pressure/ (100 × Δ area/area) mm Hg/%). Sixteen volunteers (age 35.2±13.1 years) underwent the oscillometric measurements and brachial ultrasound at rest and under nitroglycerin (NTG) administration. Oscillometric measurement was performed twice on different days. The rest eA correlated with ultrasound-measured brachial artery area (r=0.77, P<0.001). Rest eA and VE measurement showed good reproducibility (eA: intraclass correlation coefficient (ICC)=0.88, VE: ICC=0.78). Under NTG stress, eA was significantly increased (12.3±3.0 vs. 17.1±4.6 mm2, P<0.001), and this was similar to the case with ultrasound evaluation (4.46±0.72 vs. 4.73±0.75 mm, P<0.001). VE was also decreased (0.81±0.16 vs. 0.65±0.11 mm Hg/%, P<0.001) after NTG. Cross-sectional vascular area calculated using this automated oscillometric measurement correlated with ultrasound measurement and showed good reproducibility. Therefore, this is a reliable approach and this modality may have practical application to automatically assess muscular artery diameter and elasticity in clinical or epidemiological settings. PMID:25693851

  4. Blockade of the brachial plexus abolishes activation of specific brain regions by electroacupuncture at LI4: a functional MRI study

    PubMed Central

    Gu, Weidong; Jiang, Wei; He, Jingwei; Liu, Songbin; Wang, Zhaoxin

    2015-01-01

    Objective Our aim was to test the hypothesis that electroacupuncture (EA) at acupuncture point LI4 activates specific brain regions by nerve stimulation that is mediatied through a pathway involving the brachial plexus. Methods Twelve acupuncture naive right-handed volunteers were allocated to receive three sessions of EA at LI4 in a random different order (crossover): (1) EA alone (EA); EA after injection of local anaesthetics into the deltoid muscle (EA+LA); and (3) EA after blockade of the brachial plexus (EA+NB). During each session, participants were imaged in a 3 T MRI scanner. Brain regions showing change in blood oxygen level-dependent (BOLD) signal (activation) were identified. Subjective acupuncture sensation was quantified after functional MRI scanning was completed. Results were compared between the three sessions for each individual, and averaged. Results Blockade of the brachial plexus inhibited acupuncture sensation during EA. EA and EA+LA activated the bilateral thalamus, basal ganglia, cerebellum and left putamen, whilst no significant activation was observed during EA+NB. The BOLD signal of the thalamus correlated significantly with acupuncture sensation score during EA. Conclusions Blockade of the brachial plexus completely abolishes patterns of brain activation induced by EA at LI4. The results suggest that EA activates specific brain regions through stimulation of the local nerves supplying the tissues at LI4, which transmit sensory information via the brachial plexus. Trial registration number ChiCTR-OO-13003389. PMID:26464415

  5. Supplementation with omega-3 polyunsaturated fatty acids augments brachial artery dilation and blood flow during forearm contraction.

    PubMed

    Walser, Buddy; Giordano, Rose M; Stebbins, Charles L

    2006-06-01

    Omega-3 polyunsaturated fatty acids such as docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) have beneficial effects on the heart and vasculature. We tested the hypothesis that 6 weeks of dietary supplementation with DHA (2.0 g/day) and EPA (3.0 g/day) enhances exercise-induced increases in brachial artery diameter and blood flow during rhythmic exercise. In seven healthy subjects, blood pressure, heart rate and brachial artery diameter, blood flow, and conductance were assessed before and during the last 30 s of 90 s of rhythmic handgrip exercise (30% of maximal handgrip tension). Blood pressure (MAP), heart rate (HR), and brachial artery vascular conductance were also determined. This paradigm was also performed in six other healthy subjects who received 6 weeks of placebo (safflower oil). Placebo treatment had no effect on any variable. DHA and EPA supplementation enhanced contraction-induced increases in brachial artery diameter (0.28+/-0.04 vs. 0.14+/-0.03 mm), blood flow (367+/-65 vs. 293+/-55 ml min-1) and conductance (3.86+/-0.71 vs. 2.89+/-0.61 ml min-1 mmHg-1) (P<0.05). MAP and HR were unchanged. Results indicate that treatment with DHA and EPA enhances brachial artery blood flow and conductance during exercise. These findings may have implications for individuals with cardiovascular disease and exercise intolerance (e.g., heart failure). PMID:16770472

  6. 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 human trials necessary to demonstrate "efficacy" for a beneficial effect on the long term adverse health effects of radiation, such as the development of cancer, cataracts, etc., is expected to take particularly long periods of time. To avoid the long time delay in the development of new drugs as countermeasures for radiation induced adverse health effects, the NSBRI Center for Acute Radiation Research (CARR) is currently focused on the use of drugs that have already been approved for human use by the FDA. Currently there are no approved countermeasures for external radiation exposure by the US Army or by NASA. The appropriate medications for symptoms of the Acute Radiation Syndrome (ARS) due to exposure to solar particle event (SPE) radiation are unknown, but there are medications appropriate for ARS symptoms caused by exposure to conventional ra-diation. The Armed Forces Radiobiology Research Institute (AFRRI) has medical guidelines for ARS medications (http://www.afrri.usuhs.mil/outreach/guidance.htm#policies), as does the US Dept. of Health and Human Services (the REMM (Radiation Event Medical Manage-ment) site (http://www.remm.nlm.gov). Supportive care when ARS symptoms develop include the administration of antimicrobial agents (which can include systemic antibiotics [especially those directed at gram-negative bacteria]), antiemetic agents, antidiarrheal agents, fluids, elec-trolytes, analgesic agents and topical burn creams (Waselenko, J.K. et al. Ann. Intern. Med. 140: 1037, 2004). For nausea and vomiting, serotonin receptor antagonists (5HT3 receptor antagonists) are very effective prophylaxis. There are two drugs that have been approved by the FDA (Zofran and Kytril) for radiation induced nausea and vomiting. Kytril (granisetron) is preferred by the US Army and is currently maintained in the US National Stockpile. Both of these drugs are known to stop retching and vomiting when given either before or after irradi-ation, even when vomiting and/or retching are occurring. Immune suppression can occur due to declines in white blood cells and infection is a possibility. Of particular importance is the radiation induced decline in neutrophil counts. Methods for controlling infection during the critical neutropenic phase can be used. Investigations of the CARR grant use FDA approved drugs for ARS symptoms in animals exposed to SPE radiations. ACKNOWLEDGEMENTS: The research investigations of the CARR grant are supported by the National Space Biomedical Research Institute (NSBRI) through NASA NCC 9-58.

  7. Gamma radiation induced micronuclei and erythrocyte cellular abnormalities in the fish Catla catla.

    PubMed

    Anbumani, S; Mohankumar, Mary N

    2012-10-15

    Ionizing radiation induced DNA damage in fishes is a scarcely studied topic and very few studies are available in fishes exposed to ionizing radiation using the erythrocyte micronucleus assay under laboratory conditions. Since radionuclides released accidentally or during a nuclear disaster can contaminate inland water bodies, biomonitoring methods are required for assessing the impacts of high and low levels of radiation that may ultimately result in ionizing radiation exposure to both humans and non-human biota. Fresh water fish, Catla catla were subjected to protracted (0.002 Gy/min) and acute (3.2 Gy/min) gamma radiation to a total dose of 5 Gy. Peripheral blood samples were collected at different intervals (days 3, 6, 12, 18, 30, 45, 90, 135, 202) and analyzed by the erythrocyte micronucleus assay. Nuclear anomalies observed were micronuclei (MN), deformed nuclei (DN), nuclear bud (NBu), nuclear bridge (NBr), vacuolated nucleus (VN), binucleated cell (BNC), apoptotic cells (AC) while cytoplasmic abnormalities detected were vacuolated cytoplasm (VC), anisochromasia (AN), echinocytes (EC) and enucleus (EN). Both exposures caused a statistically significant increase in nuclear and cytoplasmic abnormalities that correlated with micronucleus and other nuclear anomalies. However, the extent of damage is higher after an acute exposure lasting for a longer period leading to apoptosis. Nuclear and cytoplasmic abnormalities are the resultants of gamma radiation induced genotoxicity and cytotoxicity. PMID:22771702

  8. Ionizing radiation induced long-term alterations in the adult rat rostral migratory stream.

    PubMed

    Balentova, Sona; Hajtmanova, Eva; Trylcova, Ria; Adamkov, Marian; Lehotsky, Jan

    2014-01-01

    Ionizing radiation can induce significant injury to normal brain structures. To assess radiation-induced late effects, adult male Wistar rats received whole-body exposure with fractionated doses of gamma rays (a total dose of 4Gy) and were investigated thirty, sixty and ninety days later. Immunohistochemistry and confocal microscopy were used to determine the density of neuroblasts derived from the anterior subventricular zone (SVZa) and brain resident microglia distributed along and/or adjacent to subventricular zone-olfactory bulb axis (SVZ-OB axis). Cell counting was performed in four anatomical parts along the well defined pathway, known as the rostral migratory stream (RMS) represented by the SVZa, vertical arm, elbow and horizontal arm of the RMS. Strong overdistribution of neuroblasts was seen in the SVZa thirty and sixty days after irradiation replaced by a steep decline in the following parts of the RMS and the highest decrease ninety days after radiation treatment along the entire SVZ-OB axis. Radiation treatment led to a decline or loss of microglia in almost all counted parts through the entire experiment. Results showed that ultimate decline of the SVZa descendants and loss of microglia suggests a contributory role of reduced neurogenesis in the development of radiation-induced late effects. PMID:24080197

  9. Sorafenib Enhances Radiation-Induced Apoptosis in Hepatocellular Carcinoma by Inhibiting STAT3

    SciTech Connect

    Huang, Chao-Yuan; Department of Radiological Technology, Yuanpei University, Hsinchu, Taiwan ; Lin, Chen-Si; Tai, Wei-Tien; Hsieh, Chi-Ying; National Center of Excellence for Clinical Trial and Research, National Taiwan University Hospital, Taipei, Taiwan ; Shiau, Chung-Wai; Cheng, Ann-Lii; National Center of Excellence for Clinical Trial and Research, National Taiwan University Hospital, Taipei, Taiwan ; Chen, Kuen-Feng; National Center of Excellence for Clinical Trial and Research, National Taiwan University Hospital, Taipei, Taiwan

    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.

  10. Desalination by electrodialysis with the ion-exchange membrane prepared by radiation-induced graft polymerization

    NASA Astrophysics Data System (ADS)

    Choi, Seong-Ho; Han Jeong, Young; Jeong Ryoo, Jae; Lee, Kwang-Pill

    2001-01-01

    Ion-exchange membranes modified with the triethylamine [-N(CH 2CH 3) 3] and phosphoric acid (-PO 3 H) groups were prepared by radiation-induced grafting of glycidyl methacrylate (GMA) onto the polyolefin nonwavon fabric (PNF) and subsequent chemical modification of poly(GMA) graft chains. The physical and chemical properties of the GMA-grafted PNF and the PNF modified with ion-exchange groups were investigated by SEM, XPS, TGA, and DSC. Furthermore, electrochemical properties such as specific electric resistance, transport number of K +, and desalination were examined. The grafting yield increased with increasing reaction time and reaction temperature. The maximum grafting yield was obtained with 40% (vol.%) monomer concentration in dioxane at 60°C. The content of the cation- and anion-exchange group increased with increasing grafting yield. Electrical resistance of the PNF modified with TEA and -PO 3 H group decreased, while the water uptake (%) increased with increasing ion-exchange group capacities. Transport number of the PNF modified with ion-exchange group were the range of ca. 0.82-0.92. The graft-type ion-exchange membranes prepared by radiation-induced graft copolymerization were successfully applied as separators for electrodialysis.

  11. 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.

  12. Enhanced radiation-induced cell killing by Herbimycin A pre-treatment

    NASA Astrophysics Data System (ADS)

    Noguchi, Miho; Hirayama, Ryoichi; Druzhinin, Sergey; Okayasu, Ryuichi

    2009-12-01

    Herbimycin A (HA), as in Geldanamycin, binds to conserved pockets of heat shock protein 90 (Hsp90) and inhibits its chaperone functions. Hsp90 plays an integral role in cancer cell growth and survival, because it maintains the stability of several key proteins by its chaperone's activity. It is known that some of the proteins associated with radiation responses are functionally stabilized by Hsp90. In this study, we investigated the effect of HA on radiosensitivity in human cancer cells and the mechanism related to the sensitization. In order to gain a mechanistic insight of this sensitization, we examined repair of DNA double-strand breaks (DSBs) in irradiated human cancer cells pre-treated with HA, as unrepaired DSBs are thought to be the main cause of radiation-induced cell death. Cellular radiosensitivity was determined by clonogenic assay, and the DSB rejoining kinetics was examined by constant field gel electrophoresis. SQ-5, a lung squamous carcinoma cell line, showed synergistic increase in radiosensitivity when cells were pre-treated with HA. In addition, HA significantly inhibited repair of radiation-induced DSBs. These results suggest that the combination of HA and ionizing radiation may be a useful therapeutic strategy for treating certain cancer cells.

  13. Protection from Radiation-Induced Pulmonary Fibrosis by Peripheral Targeting of Cannabinoid Receptor-1.

    PubMed

    Bronova, Irina; Smith, Brett; Aydogan, Bulent; Weichselbaum, Ralph R; Vemuri, Kiran; Erdelyi, Katalin; Makriyannis, Alex; Pacher, Pal; Berdyshev, Evgeny V

    2015-10-01

    Radiation-induced pulmonary fibrosis (RIF) is a severe complication of thoracic radiotherapy that limits its dose, intensity, and duration. The contribution of the endocannabinoid signaling system in pulmonary fibrogenesis is not known. Using a well-established mouse model of RIF, we assessed the involvement of cannabinoid receptor-1 (CB1) in the onset and progression of pulmonary fibrosis. Female C57BL/6 mice and CB1 knockout mice generated on C57BL/6 background received 20 Gy (2 Gy/min) single-dose thoracic irradiation that resulted in pulmonary fibrosis and animal death within 15 to 18 weeks. Some C57BL/6 animals received the CB1 peripherally restricted antagonist AM6545 at 1 mg/kg intraperitoneally three times per week. Animal survival and parameters of pulmonary inflammation and fibrosis were evaluated. Thoracic irradiation (20 Gy) was associated with marked pulmonary inflammation and fibrosis in mice and high mortality within 15 to 18 weeks after exposure. Genetic deletion or pharmacological inhibition of CB1 receptors with a peripheral CB1 antagonist AM6545 markedly attenuated or delayed the lung inflammation and fibrosis and increased animal survival. Our results show that CB1 signaling plays a key pathological role in the development of radiation-induced pulmonary inflammation and fibrosis, and peripherally restricted CB1 antagonists may represent a novel therapeutic approach against this devastating complication of radiotherapy/irradiation. PMID:26426981

  14. Radiation-induced cognitive dysfunction: An experimental model in the old rat

    SciTech Connect

    Lamproglou, I.; Chen, Q.M.; Poisson, M.

    1995-01-01

    To develop a model of radiation-induced behavioral dysfunction. A course of whole brain radiation therapy (30 Gy/10 fractions/12 days) was administered to 26 Wistar rats ages 16-27 months, while 26 control rats received sham irradiation. Sequential behavioral studies including one-way avoidance, two-way avoidance, and a standard operant conditioning method (press-lever avoidance) were undertaken. In addition, rats were studied in a water maze 7 months postradiation therapy. Prior to radiation therapy, both groups were similar. No difference was found 1 and 3 months postradiation therapy. At 6-7 months postradiation therapy, irradiated rats had a much lower percentage of avoidance than controls for one-way avoidance (23% vs. 55%, p {le} 0.001) and two-way avoidance (18% vs. 40%, p {le} 0.01). Seven months postradiation therapy the reaction time was increased (press-lever avoidance, 11.20 s vs. 8.43 s, p {le} 0.05) and the percentage of correct response was lower (water maze, 53% vs. 82%) in irradiated rats compared with controls. Pathological examination did not demonstrate abnormalities of the irradiated brains at the light microscopic level. Behavioral dysfunction affecting mainly memory can be demonstrated following conventional radiation therapy in old rats. This model can be used to study the pathogenesis of radiation-induced cognitive changes. 15 refs., 3 figs., 1 tab.

  15. 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.

  16. 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.

  17. Biological responses of human apurinic endonuclease to radiation-induced DNA damage

    SciTech Connect

    Chen, D.S.; Olkowski, Z.L.

    1994-12-31

    Ionizing radiation produces a variety of DNA damage through active oxygen species such as the superoxide radical (O{sub 2}{sup -}), the hydroxyl radical (OH), and hydrogen peroxide (H{sub 2}O{sub 2}). Previous studies showed that human AP endonuclease, a counterpart of exonuclease III, can functionally replace E. coli exonuclease III to repair methyl methanesulfonate (MMS)-induced but not H{sub 2}O{sub 2}-induced DNA damage. Reduction of radiation-induced cytotoxicity by human AP endonuclease in a radiation-sensitive mutant of E. coli indicated that the AP site is one of the major forms of DNA damage produced by ionizing radiation. The removal of alkylation-induced AP sites and 3{prime}-blocking deoxyribose fragments by human AP endonuclease indicates that this enzyme is playing a pivotal role in the repair of oxidative DNA damage. In the current study, we examined the biological roles of AP endonuclease as being responsible for the repair of radiation-induced DNA damage in human cells.

  18. Three-dimensional Culture Conditions Lead to Decreased Radiation Induced Crytoxicity in Human Mammary Epithelial Cells

    SciTech Connect

    Sowa, Marianne B.; Chrisler, William B.; Zens, Kyra D.; Ashjian, Emily J.; Opresko, Lee K.

    2010-05-01

    For both targeted and non-targeted exposures, the cellular responses to ionizing radiation have predominantly been measured in two dimensional monolayer cultures. Although convenient for biochemical analysis, the true interactions in vivo depend upon complex interactions between cells themselves and the surrounding extra cellular matrix. This study directly compares the influence of culture conditions on radiation induced cytotoxicity following exposure to low-LET ionizing radiation. Using a three dimensional (3D) human mammary epithelial tissue model, we have found a protective effect of 3D cell culture on cell survival after irradiation. The initial state of the cells (i.e., 2D vs. 3D culture) at the time of irradiation does not alter survival, nor does the presence of extracellular matrix during and after exposure to dose, but long term culture in 3D which offers significant reduction in cytotoxicity at a given dose (e.g. ~4 fold increased survival at 5 Gy). The cell cycle delay induced following exposure to 2 and 5 Gy was almost identical between 2D and 3D culture conditions and cannot account for the observed differences in radiation responses. However the amount of apoptosis following radiation exposure is significantly decreased in 3D culture relative to the 2D monolayer after the same dose. A likely mechanism of the cytoprotective effect afforded by 3D culture conditions is the down regulation of radiation induced apoptosis in 3D structures

  19. Punica granatum peel extract protects against ionizing radiation-induced enteritis and leukocyte apoptosis in rats.

    PubMed

    Toklu, Hale Z; Sehirli, Ozer; Ozyurt, Hazan; Mayadağli, A Alpaslan; Ekşioğlu-Demiralp, Emel; Cetinel, Sule; Sahin, Hülya; Yeğen, Berrak C; Ulusoylu Dumlu, Melek; Gökmen, Vural; Sener, Göksel

    2009-07-01

    Radiation-induced enteritis is a well-recognized sequel of therapeutic irradiation. Therefore we examined the radioprotective properties of Punica granatum peel extract (PPE) on the oxidative damage in the ileum. Rats were exposed to a single whole-body X-ray irradiation of 800 cGy. Irradiated rats were pretreated orally with saline or PPE (50 mg/kg/day) for 10 days before irradiation and the following 10 days, while control rats received saline or PPE but no irradiation. Then plasma and ileum samples were obtained. Irradiation caused a decrease in glutathione and total antioxidant capacity, which was accompanied by increases in malondialdehyde levels, myeloperoxidase activity, collagen content of the tissue with a concomitant increase 8-hydroxy-2'-deoxyguanosine (an index of oxidative DNA damage). Similarly, pro-inflammatory cytokines (TNF-alpha, IL-1beta and IL-6) and lactate dehydrogenase were elevated in irradiated groups as compared to control. PPE treatment reversed all these biochemical indices, as well as histopathological alterations induced by irradiation. Furthermore, flow cytometric measurements revealed that leukocyte apoptosis and cell death were increased in irradiated animals, while PPE reversed these effects. PPE supplementation reduced oxidative damage in the ileal tissues, probably by a mechanism that is associated with the decreased production of reactive oxygen metabolites and enhancement of antioxidant mechanisms. Adjuvant therapy of PPE may have a potential to support a successful radiotherapy by protecting against radiation-induced enteritis. PMID:19478462

  20. Geraniin down regulates gamma radiation-induced apoptosis by suppressing DNA damage.

    PubMed

    Bing, So Jin; Ha, Danbee; Kim, Min Ju; Park, Eunjin; Ahn, Ginnae; Kim, Dae Seung; Ko, Ryeo Kyeong; Park, Jae Woo; Lee, Nam Ho; Jee, Youngheun

    2013-07-01

    Gamma ray irradiation triggers DNA damage and apoptosis of proliferating stem cells and peripheral immune cells, resulting in the destruction of intestinal crypts and lymphoid system. Geraniin is a natural compound extracts from an aquatic plant Nymphaea tetragona and possesses good antioxidant property. In this study, we demonstrate that geraniin rescues radiosensitive splenocytes and jejunal crypt cells from radiation-induced DNA damage and apoptosis. Isolated splenocytes from C57BL/6 mice treated with geraniin were protected against radiation injury of 2 Gy irradiation through the enhancement of the proliferation and attenuation of DNA damage. Also, geraniin inhibited apoptosis in radiosensitive splenocytes by reducing the expression level and immunoreactivity of proapoptotic p53 and Bax and increasing those of anti-apoptotic Bcl-2. In mice exposed to radiation, geraniin treatment protected splenocytes and intestinal crypt cells from radiation-induced cell death. Our results suggest that geraniin presents radioprotective effects by regulating DNA damage on splenocytes, exerting immunostimulatory capacities and inhibiting apoptosis of radiosensitive immune cells and jejunal crypt cells. Therefore, geraniin can be a radioprotective agent against γ-irradiation exposure. PMID:23541438

  1. Caffeine ameliorates radiation-induced skin reactions in mice but does not influence tumour radiation response.

    PubMed

    Hebbar, S A; Mitra, A K; George, K C; Verma, N C

    2002-03-01

    Intramuscular administration of caffeine at a dose of 80 mg kg(-1) body weight to the gastrocnemius muscles of Swiss mice 5 min prior to local irradiation (35 Gy) of the leg delayed the progression of radiation-induced skin reactions in such animals. While 90% epilation with reddening of the skin was noted in animals treated with radiation alone, animals pretreated with caffeine suffered only partial hair loss with slight reddening of the skin on the 16th and 20th days post-irradiation. Beyond the 28th day, damage scores in irradiated feet for both the groups were similar (score 3) and remained unchanged until the 32nd day and then decreased and disappeared completely in both treatment groups by the 40th day after irradiation. In addition, the effect of caffeine on the radiation response of a mouse fibrosarcoma was investigated. Results showed that intratumoral administration of caffeine at a dose of 80 mg kg(-1) body weight 5 min prior to local exposure of tumours to 10 Gy of 60Co gamma-rays did not influence the response of tumours to radiation. The present study thus showed that although caffeine ameliorated radiation-induced skin reactions in the mouse leg, it did not affect the tumour radiation response, indicating its potential application in cancer radiotherapy. PMID:11929115

  2. Apigenin ameliorates gamma radiation-induced cytogenetic alterations in cultured human blood lymphocytes.

    PubMed

    Begum, Naziya; Prasad, N Rajendra; Kanimozhi, G; Hasan, Annie Q

    2012-08-30

    The aim of the present study was to assess the protective effect of apigenin, a dietary flavone, against cytogenetic alterations in human peripheral blood lymphocytes (HPBL) induced by Cobalt-60 radiation (3Gy). Results of MTT [3-(4, 5-dimethyl-2-thiaozolyl)-2,5-diphenyl-2H tetrazolium bromide] assay revealed that 37.2μM of apigenin was found to be non-toxic in HPBL. At this dose (37.2μM) of apigenin, the LD(50) radiation dose of HPBL increased from 2.9Gy to 3.4Gy, which resulted in a DMF of 1.17. Apigenin (37.2μM) treatment 1h before irradiation significantly (p<0.05) reduced DNA damage in irradiated HPBL as measured by comet assay (% tail DNA, tail length, tail moment, and olive tail moment). Moreover, apigenin treatment significantly decreased the frequencies of dicentric (DC), acentric fragments (AF), and acentric rings (AR) in irradiated HPBL. Apigenin pretreatment also reduced the radiation-induced CBMN (cytokinesis blocked micronuclei) anomalies such as micronuclei (MNi), nucleoplasmic bridges (NPB) and nuclear buds (NBUD) in HPBL. These results also showed that there was a significant correlation between NPB and DC frequencies and MNi and AF+AR. Treatment with apigenin alone had no significant effect on DNA damage and chromosomal aberrations in HPBL. Thus, the current studies indicate that apigenin protects HPBL from radiation-induced cytogenetic alterations. PMID:22516036

  3. [The protective effects of SB203580 against mortality and radiation induced intestinal injury of mice].

    PubMed

    Chang, Jian-hui; Zhang, Heng; Guan, Fang-xia; Wang, Yue-ying; Li, De-guan; Wu, Hong-ying; Wang, Cheng-chun; Zhou, Chang-hui; Zhai, Zhi-bin; Lu, Lu; Wang, Xiao-chun; Hou, Qi; Meng, Ai-min

    2011-04-01

    This study is to investigate the protective effects of the SB203580 against radiation induced mortality and intestinal injury of mice. A total of 67 male C57BL/6 mice (20.0-22.0 g) were matched according to body weight and randomly assigned to one of three groups: control, total body irradiation exposure (IR, 7.2 Gy) only, and IR (7.2 Gy) + SB203580 (15 mg x kg(-1)). 30 days survival rate was observed in the experiment. In intestinal injury experiment, the expression levels of caspase-3, Ki67, p53 and p-p38 were assayed in the mice intestine crypts. The results showed that the 30 days survival rate was 100% (control), 0 (IR) and 40% (IR+ SB203580), separately. Compared to the IR groups, the positive cells of caspase-3, p53 and p-p38 in crypt cells decreased 33.00%, 21.78% and 34.63%, respectively. The rate of positive cells of Ki67 increased 37.96%. Significant difference was found between all of them (P < 0.01). SB203580 potently protected against radiation-induced lethal and intestinal injury in mice, and it may be a potential radio protector. PMID:21751492

  4. 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

    2016-01-01

    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. PMID:27165942

  5. Relief of radiation-induced oral mucositis in head and neck cancer.

    PubMed

    Putwatana, Panwadee; Sanmanowong, Phichanee; Oonprasertpong, Ladawal; Junda, Tiraporn; Pitiporn, Supaporn; Narkwong, Ladawan

    2009-01-01

    This study was a prospective, randomized clinical trial carried out to explore the efficacy of payayor in the prevention and relief of radiation-induced oral mucositis compared with benzydamine. Sixty patients with head and neck cancer, who have started to receive radiotherapy and met predetermined criteria, were randomly assigned into each group to use assigned products 3 times a day from the first to the last day of radiation. The first group used glycerin payayor, a Thai prepared herbal product, by dripping it into the mouth. Another group rinsed their mouths with benzydamine hydrochloride. The World Health Organization Mucositis Grading System was used to assess oral status every week and 2 weeks after radiation. Comparison of time to the onset, pain, severity, xerostomia, postponement of treatment, satisfaction of the solution, and body weight between the 2 groups was performed by t test. The average time to the onset of oral mucositis in the payayor group was significantly later, and its severity and pain score were less than those of the benzydamine group throughout the study period. Significantly higher satisfaction with the solution and higher body weight at the end of the study were shown in the payayor group. Payayor seemed to be superior to benzydamine for preventing and relieving radiation-induced oral mucositis. PMID:19104205

  6. WR-1065, the Active Metabolite of Amifostine, Mitigates Radiation-Induced Delayed Genomic Instability

    PubMed Central

    Dziegielewski, Jaroslaw; Baulch, Janet E.; Goetz, Wilfried; Coleman, Mitchell C.; Spitz, Douglas R.; Murley, Jeffrey S.; Grdina, David J.; Morgan, William F.

    2009-01-01

    Compounds that can protect cells from the effects of radiation are important for clinical use, in the event of an accidental or terrorist-generated radiation event, and for astronauts traveling in space. One of the major concerns regarding the use of radio-protective agents is that they may protect cells initially, but predispose surviving cells to increased genomic instability later. In this study we used WR-1065, the active metabolite of amifostine, to determine how protection from direct effects of high and low-LET radiation exposure influences genomic stability. When added 30 minutes before irradiation and in high concentration, WR-1065 protected cells from immediate radiation-induced effects as well as from delayed genomic instability. Lower, non-toxic concentration of WR-1065 did not protect cells from death, however it was effective in significantly decreasing delayed genomic instability in the progeny of irradiated cells. The observed increase in manganese superoxide dismutase protein levels and activity may provide an explanation for this effect. These results confirm that WR-1065 is protective against both low- and high-LET radiation-induced genomic instability in surviving cells. PMID:18845240

  7. 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.

  8. Modulating factors in the expression of radiation-induced oncogenic transformation

    SciTech Connect

    Hall, E.J.; Hei, T.K. )

    1990-08-01

    Many assays for oncogenic transformation have been developed ranging from those in established rodent cell lines where morphological alteration is scored, to those in human cells growing in nude mice where tumor invasiveness is scored. In general, systems that are most quantitaive are also the least relevant in terms of human carcinogenesis and human risk estimation. The development of cell culture systems has made it possible to assess at the cellular level the oncogenic potential of a variety of chemical, physical and viral agents. Cell culture systems afford the opportunity to identify factors and conditions that may prevent or enhance cellular transformation by radiation and chemicals. Permissive and protective factors in radiation-induced transformation include thyroid hormone and the tumor promoter TPA that increase the transformation incidence for a given dose of radiation, and retinoids, selenium, vitamin E, and 5-aminobenzamide that inhibit the expression of transformation. Densely ionizing {alpha}-particles, similar to those emitted by radon daughters, are highly effective in inducing transformations and appear to interact in a supra-additive fashion with asbestos fibers. The activation of a known dominant oncogene has not yet been demonstrated in radiation-induced oncogenic transformation. The most likely mechanism for radiation activation of an oncogene would be via the production of a chromosomal translocation. Radiation also efficiently induces deletions and may thus lead to the loss of a suppressor gene.

  9. 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. PMID:25368082

  10. 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)

  11. 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.

  12. 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.

  13. Glucose transport by radiation-induced insulinoma and clonal pancreatic beta-cells

    SciTech Connect

    Meglasson, M.D.; Manning, C.D.; Najafi, H.; Matschinsky, F.M.

    1986-12-01

    Sugar uptake was measured in dispersed cells prepared from radiation-induced insulinomas transplantable in NEDH rats and in three clonal beta-cell lines maintained in continuous culture (RIN m5F, RIN 1046, HIT). Uptake of D-glucose and 3-O-methyl-D-glucose by insulinoma cells was rapid so that the intracellular concentration of D-hexoses approximated the concentration in the incubation medium by 15-30 s. L-Glucose was taken up only slowly. 3-O-methyl-D-glucose uptake by RIN m5F, RIN 1046, and HIT cells was slow; with 1 mM 3-O-methylglucose in the medium, equilibrium was attained at 20 min, but with 10 mM 3-O-methylglucose, equilibrium was not attained even at 20 min. In HIT cells incubated with D-glucose for 30 min, the intracellular concentration of glucose was less than the medium glucose concentration, indicating glucose transport is a nonequilibrium reaction in this cell line. These data indicate that radiation-induced insulinoma cells retain the capacity of normal beta-cells to transport sugar at high rates. RIN m5F, RIN 1046, and HIT cells transport sugar slowly, however, and thus differ from normal beta-cells. In RIN m5F, RIN 1046, and HIT cells, unlike in normal beta-cells, glucose transport may be the site regulating glucose metabolism.

  14. 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.

  15. WR-1065, the active metabolite of amifostine, mitigates radiation-induced delayed genomic instability.

    PubMed

    Dziegielewski, Jaroslaw; Baulch, Janet E; Goetz, Wilfried; Coleman, Mitchell C; Spitz, Douglas R; Murley, Jeffrey S; Grdina, David J; Morgan, William F

    2008-12-15

    Compounds that can protect cells from the effects of radiation are important for clinical use, in the event of an accidental or terrorist-generated radiation event, and for astronauts traveling in space. One of the major concerns regarding the use of radio-protective agents is that they may protect cells initially, but predispose surviving cells to increased genomic instability later. In this study we used WR-1065, the active metabolite of amifostine, to determine how protection from direct effects of high- and low-LET radiation exposure influences genomic stability. When added 30 min before irradiation and in high concentrations, WR-1065 protected cells from immediate radiation-induced effects as well as from delayed genomic instability. Lower, nontoxic concentrations of WR-1065 did not protect cells from death; however, it was effective in significantly decreasing delayed genomic instability in the progeny of irradiated cells. The observed increase in manganese superoxide dismutase protein levels and activity may provide an explanation for this effect. These results confirm that WR-1065 is protective against both low- and high-LET radiation-induced genomic instability in surviving cells. PMID:18845240

  16. 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

    2015-12-01

    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. PMID:26488306

  17. 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. PMID:25261614

  18. 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

    2007-04-01

    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. PMID:17307150

  19. 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.

  20. 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.

  1. Radiation-induced loss of unsaturation in 1,2-polybutadiene

    NASA Technical Reports Server (NTRS)

    Golub, M. A.; Cormia, R. D.

    1982-01-01

    The radiation induced loss of unsaturation and methyl production in 1,2-polybutadiene (VB) was studied using IR spectroscopy. It was found that G(-1,2), which depends on the initial vinyl content, decreased from approximately 550 for VB with 98.5% 1,2 initially, to approximately 270 for VB with 85% 1,2 initially. G(-trans-1,4) ranged from approximately 21 for VB with 14% trans-1,4 to nearly zero for VB with less than 1% trans-1,4 initially. Methyl production was found to equal one methyl group formed for every 4-5 vinyl units consumed in the radiation-cyclized VB, in contrast to one methyl formed for every two vinyls reacted during cationic cyclization to give monocyclic structures. The IR spectra of gamma-irradiated VB were very similar to the spectra of UV-irradiated or thermally-treated VB at the same residual vinyl contents. It is suggested that the radiation-induced cyclization of VB occurs by a nonionic, nonradical 'energy chain' mechanism, which apparently holds for the cyclization of VB, whether induced by gamma-rays, UV radiation, or heat.

  2. The role of protein kinase C alpha translocation in radiation-induced bystander effect

    PubMed Central

    Fang, Zihui; Xu, An; Wu, Lijun; Hei, Tom K.; Hong, Mei

    2016-01-01

    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. PMID:27165942

  3. 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. PMID:25483031

  4. A Practical Approach to the Management of Radiation-Induced Hemorrhagic Cystitis.

    PubMed

    Liem, Xavier; Saad, Fred; Delouya, Guila

    2015-09-01

    Radiation-induced hemorrhagic cystitis (HC) is a complication of pelvic radiotherapy, mainly for prostate and uterine cancers. In the acute phase, patients feel urinary urgency and bladder pain. This phase is reversible after radiotherapy. In the chronic stage, an irritative syndrome is coupled with hematuria during the 2-10 years following radiotherapy. Cystoscopy shows white and frosted mucosa with telangiectasia. The incidence is estimated at 5 % or less. It is suggested that the radiation oncologist reviews the dosimetry plan to validate that the lesions coincide with significant radiation exposure confirming diagnosis of radiation-induced HC. The treatment for HC is first symptomatic, with bladder lavage, clot evacuation, coagulation via cystoscopy and blood transfusions if necessary. Subsequently, hyaluronic acid bladder instillation can be done with little toxicity. Hyperbaric oxygen therapy delivers pure oxygen to patients in a pressurized cabin, promoting angio-neogenesis and lowering hypoxia to the irradiated tissues. The clinical response rate is estimated to be around 80 %. Nevertheless, this approach is limited by the low availability, and length of treatment. While surgery remains an effective treatment for HC, it is the last option because of the high morbidity and mortality risks. Prospective studies need to be conducted to identify and evaluate new interventions, particularly for HC. PMID:26271398

  5. Gene expression and hormone autonomy in radiation-induced tumors of Arabidopsis thaliana

    SciTech Connect

    Persinger, S.M.; Town, C.D. )

    1989-04-01

    In order to study the molecular genetics of factor controlling plant cell growth, we have isolated a group of radiation-induced tumors from Arabidopsis thaliana. Tumors appeared on plants derived from {sup 60}Co gamma-irradiated seed or seedlings, and are capable of hormone-autonomous growth in culture. We have used vertebrate oncogene probes to explore the hypothesis that the tumors arose by the radiation-induced activation of growth-regulating plant oncogenes. One probe, int-2, was used to isolate cDNA clones representing an mRNA differentially expressed between tumors and hormone-dependent callus tissue. The genomic organization and function of this and other differentially expressed Arabidopsis sequences are being further characterized. A second area of study concerns the hormonal status of individual tumors. Tumor tissue varies in color, texture, and degree of differentiation: while some tumors appear undifferentiated, one consistently produces roots, and others occasionally develop shoots or leaflets. The tumors have characteristic growth rates on hormone-free medium, and growth in response to exogenous hormones differs among the tumors themselves and from wild-type. Characterization of the relationships between hormonal status, morphogenesis, and gene expression should yield valuable insights into the mechanisms regulating plant growth and development.

  6. Vulnerability of rare-earth-doped fibers for space missions: origins of radiation-induced attenuation

    NASA Astrophysics Data System (ADS)

    Ouerdane, Y.; Girard, S.; Tortech, B.; Robin, T.; Marcandella, C.; Boukenter, A.; Cadier, B.; Meunier, J.-P.; Crochet, P.

    2009-05-01

    We characterized the responses of different types of rare-earth doped fibers (Yb, Er and Er/Yb) to various types of radiations like UV, gamma-rays, X-rays and protons. The understanding of the radiation-induced effects in this class of optical fibers is necessary as they are possible candidates for use as part of fiber-based systems like gyroscopes that will have to operate in space environment. For all types of irradiations, the main effect is an increase of the linear absorption of these waveguides due to the generation of point defects in the core and cladding. We characterize the growth and decay kinetics of the radiation-induced attenuation during and after irradiation for various compositions of optical fibers. In this paper, we particularly investigate the relative influence of the rare-earth ions (Er, Yb or Er/Yb) and of the glass matrix dopants (Al, P, ...) on the optical degradation induced by ultraviolet laser exposure at 5 eV. This has been done by using a set of five prototype optical fibers designed by iXFiber SAS to enlighten the role of these parameters. Additional spectroscopic tools like confocal microscopy of luminescence are also used to detect possible changes in the spectroscopy of the rare-earth ions and their consequence on the functionality of the active optical fibers.

  7. A two-mutation model of radiation-induced acute myeloid leukemia using historical mouse data.

    PubMed

    Dekkers, Fieke; Bijwaard, Harmen; Bouffler, Simon; Ellender, Michele; Huiskamp, Ren; Kowalczuk, Christine; Meijne, Emmy; Sutmuller, Marjolein

    2011-03-01

    From studies of the atomic bomb survivors, it is well known that ionizing radiation causes several forms of leukemia. However, since the specific mechanism behind this process remains largely unknown, it is difficult to extrapolate carcinogenic effects at acute high-dose exposures to risk estimates for the chronic low-dose exposures that are important for radiation protection purposes. Recently, it has become clear that the induction of acute myeloid leukemia (AML) in CBA/H mice takes place through two key steps, both involving the Sfpi1 gene. A similar mechanism may play a role in human radiation-induced AML. In the present paper, a two-mutation carcinogenesis model is applied to model AML in several data sets of X-ray- and neutron-exposed CBA/H mice. The models obtained provide good fits to the data. A comparison between the predictions for neutron-induced and X-ray-induced AML yields an RBE for neutrons of approximately 3. The model used is considered to be a first step toward a model for human radiation-induced AML, which could be used to estimate risks of exposure to low doses. PMID:20842369

  8. 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.

  9. Cytokine profiling for prediction of symptomatic radiation-induced lung injury

    SciTech Connect

    Hart, Justin P.; Broadwater, Gloria; Rabbani, Zahid; Moeller, Benjamin J.; Clough, Robert; Huang, Dale; Sempowski, Gregory A.; Dewhirst, Mark; Pizzo, Salvatore V.; Vujaskovic, Zeljko; Anscher, Mitchell S. . E-mail: anscher@radonc.duke.edu

    2005-12-01

    Purpose: To analyze plasma cytokine profiles before the initiation of radiation therapy to define a cytokine phenotype that correlates with risk of developing symptomatic radiation-induced lung injury (SRILI). Methods and Materials: Symptomatic radiation-induced lung injury was evaluated in 55 patients (22 with SRILI and 33 without SRILI), according to modified National Cancer Institute common toxicity criteria. These plasma samples were analyzed by the multiplex suspension bead array system (Bio-Rad Laboratories; Hercules, CA), which included the following cytokines: interleukin (IL)-1{beta}, IL-2, IL-4, IL-5, IL-6, IL-7, IL-8, IL-10, IL-12p70, IL-13, IL-17, granulocyte/macrophage colony-stimulating factor, interferon-{gamma}, monocyte chemotactic protein 1, macrophage inflammatory protein 1{beta}, tumor necrosis factor {alpha}, and granulocyte colony-stimulating factor. Results: Significant differences in the median values of IL-8 were observed between patients with and without SRILI. Patients who did not develop SRILI had approximately fourfold elevated levels of IL-8 as compared with patients who did subsequently develop SRILI. Significant correlations were not found for any other cytokine in this study, including transforming growth factor {beta}1. Conclusions: Patients with lower levels of plasma IL-8 before radiation therapy might be at increased risk for developing SRILI. Further studies are necessary to determine whether IL-8 levels are predictive of SRILI in a prospective trial and whether this marker might be used to determine patient eligibility for dose escalation.

  10. 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. PMID:26613604

  11. 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

  12. 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.

  13. 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.

  14. 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

  15. STAT3 Blockade Inhibits Radiation-Induced Malignant Progression in Glioma.

    PubMed

    Lau, Jasmine; Ilkhanizadeh, Shirin; Wang, Susan; Miroshnikova, Yekaterina A; Salvatierra, Nicolas A; Wong, Robyn A; Schmidt, Christin; Weaver, Valerie M; Weiss, William A; Persson, Anders I

    2015-10-15

    High grade gliomas (HGG) are classified into four subgroups based on transcriptional signatures and phenotypic characteristics. In particular, the proneural-to-mesenchymal transition (PMT) is associated with increased malignancy, poor prognosis, and disease recurrence, but the underlying causes of PMT are still unclear. In this study, we investigated whether radiotherapy promotes PMT using a genetically engineered mouse model of proneural HGG. We found that cranial ionizing radiation induced robust and durable PMT in tumors. Additionally, we isolated primary proneural HGG cells from mouse and human tumors and demonstrate that radiation induced a sustained cell-intrinsic mesenchymal transition associated with increased invasiveness and resistance to the alkylating agent temozolomide. Expectedly, irradiation-induced PMT was also associated with activation of the STAT3 transcription factor, and the combination of STAT3 blockade using JAK2 inhibitors with radiation abrogated the mesenchymal transition and extended survival of mice. Taken together, our data suggest that clinical JAK2 inhibitors should be tested in conjunction with radiation in patients with proneural HGG as a new strategy for blocking the emergence of therapy-resistant mesenchymal tumors at relapse. PMID:26282165

  16. 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.

  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. Radioprotector WR1065 reduces radiation-induced mutations at the hypoxanthine-guanine phosphoribosyl transferase locus in V79 cells

    SciTech Connect

    Grdina, D.J.; Hill, C.K.; Peraino, C. ); Biserka, N. ); Wells, R.L. . Dept. of Radiology and Radiation Biology)

    1985-06-01

    N-(2-mercaptoethyl)-1,3-diaminopropane (WR1065) protects against radiation-induced cell killing and mutagenesis at the hypoxanthine-guanine phosphoribosyl transferase (HGPRT) locus in V79 Chinese hamster lung fibroblast cells. WR1065 (4 mm) was found to be effective in protecting against radiation-induced cell lethality only if present during irradiation. No protective effect was observed if the protector was added within 5 min after irradiation or 3 h later. The effect of WR1065 on radiation-induced mutation, expressed as resistance to the cytotoxic purine analogue 6-thioguanine (HGPRT), was also investigated. This agent was effective in reducing radiation-induced mutations regardless of when it was administered. Following 10 Gy of /sup 60/Co ..gamma..-rays, the mutation frequencies observed per 10/sup 6/ survivors were 77 +- 8, 27 +- 6, 42 +- 7, and 42 +- 7 for radiation only, and WR1065 present during, immediately after, or 3 h after irradiation. These data suggest that although a segment of radiation-induced damage leading to reproductive death cannot be modulated through the postirradiation action of WR1065, processes leading to the fixation of gross genetic damage and mutation induction in surviving cells can be effectively altered and interfered with leading to a marked reduction in mutation frequency.

  19. Protective effect of zingerone, a dietary compound against radiation induced genetic damage and apoptosis in human lymphocytes.

    PubMed

    Rao, Bhuvanagiri Nageshwar; Archana, Parampalli Raghavendra; Aithal, Balkudru Kiran; Rao, Bola Sadashiva Satish

    2011-04-25

    Zingerone a dietary compound was investigated for its ability to protect against radiation induced genotoxicity and apoptosis in human lymphocytes growing in vitro. The radiation antagonistic potential of zingerone was assessed by alkaline comet, cytokinesis-block micronucleus, apoptosis and reactive oxygen species inhibition assays. Treatment of lymphocytes with zingerone (10?g/ml) prior exposure to 2Gy gamma radiation resulted in a significant reduction of frequency of micronuclei as compared to the control set of cells evaluated by cytokinesis blocked micronucleus assay. Similarly, treatment of lymphocytes with zingerone prior to radiation exposure showed significant decrease in the DNA damage as assessed by comet parameters, such as percent tail DNA and Olive tail moment. Further, treatment with zingerone (10?g/ml) before irradiation significantly decreased the percentage of apoptotic cells analyzed microscopically method and by DNA ladder assay. Similarly, the radiation induced reactive oxygen species levels were significantly (P<0.01) inhibited by zingerone. Our study demonstrates the protective effect of zingerone against radiation induced DNA damage and antiapoptotic effect in human lymphocytes, which may be partly attributed to scavenging of radiation induced free radicals and also by the inhibition of radiation induced oxidative stress. PMID:21335001

  20. 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.

  1. RELATION OF BRACHIAL AND DIGITAL MEASURES OF VASCULAR FUNCTION IN THE COMMUNITY: THE FRAMINGHAM HEART STUDY

    PubMed Central

    Hamburg, Naomi M.; Palmisano, Joseph; Larson, Martin G.; Sullivan, Lisa M.; Lehman, Birgitta T.; Vasan, Ramachandran S.; Levy, Daniel; Mitchell, Gary F.; Vita, Joseph A.; Benjamin, Emelia J.

    2011-01-01

    Impaired vascular function contributes to the development of clinical cardiovascular disease. The relation between vasodilator function assessed non-invasively in the brachial and digital arteries remains incompletely defined. In the Framingham Offspring, Third Generation and Omni cohorts, we measured flow-mediated dilation (FMD) (n=7031, age 48±13 years, 19-88 years, 54% women) and peripheral arterial tonometry (PAT) ratio (n=4352, 55±16 years, 19-90 years, 51% women). Abnormal vascular function for each measure was defined by the sex-specific 5th percentile in a reference group free of conventional cardiovascular risk factors. The prevalence of abnormal FMD but not abnormal PAT ratio was higher with advancing age. In multivariable models, higher body mass index (BMI) was associated with a higher prevalence of both abnormal FMD and PAT ratio. Additional correlates of abnormal FMD included increasing age and higher systolic blood pressure. In contrast, correlates of abnormal PAT ratio included lower systolic blood pressure, increasing total/HDL cholesterol ratio, diabetes, smoking, and lipid-lowering medication. Whereas women had higher FMD and PAT ratio compared with men, using sex-specific reference values women had a higher prevalence of abnormal brachial and digital vascular function. In participants who had concurrent testing (n=1843), PAT ratio was not significantly associated with FMD in multivariable models. In this large, community-based cohort, brachial and digital measures of vascular function had differing relations with cardiovascular risk factors and were nearly uncorrelated with each other. These results suggest that FMD and PAT provide distinct information regarding vascular function in conduit versus smaller digital vessels. PMID:21263120

  2. Influence of prior anterograde shear rate exposure on exercise-induced brachial artery dilation

    PubMed Central

    Ade, Carl J; Brown, Michael G; Ederer, Austin K; Hardy, Rachel N; Reiter, Landon K; Didier, Kaylin D

    2015-01-01

    Shear rate can elicit substantial adaptations to vascular endothelial function. Recent studies indicate that prior exposure to anterograde flow and shear increases endothelium-dependent flow-mediated dilation at rest and that anterograde shear can create an anti-atherosclerotic and provasodilatory state. The primary aim of the present study was therefore to determine the effects of prior exposure to anterograde shear on exercise-induced brachial artery dilation, total forearm blood flow (FBF), and vascular conductance (FVC) during dynamic handgrip exercise. Eight men completed a constant-load exercise test corresponding to 10% maximal voluntary contraction, prior to (baseline) and following a 40 min shear rate intervention (post-SRI) achieved via unilateral forearm heating, which has previously been shown to increase anterograde shear rate in the brachial artery. During the SRI, anterograde shear rate increased 60.9 ± 29.2 sec−1 above baseline (P < 0.05). Post-SRI, the exercise-induced brachial artery vasodilation was significantly increased compared to baseline (4.1 ± 0.7 vs. 4.3 ± 0.6 mm, P < 0.05). Post-SRI FBF mean response time (33.2 ± 16.0 vs. 23.0 ± 11.8 sec, P < 0.05) and FVC mean response time (31.1 ± 12.8 20.2 ± 10.7 sec, P < 0.05) at exercise onset were accelerated compared to baseline. These findings demonstrate that prior exposure to anterograde shear rate increases the vascular responses to exercise and supports the possible beneficial effects of anterograde shear rate in vivo. PMID:26009637

  3. Use of ankle brachial pressure index to predict cardiovascular events and death: a cohort study.

    PubMed Central

    Leng, G. C.; Fowkes, F. G.; Lee, A. J.; Dunbar, J.; Housley, E.; Ruckley, C. V.

    1996-01-01

    OBJECTIVE: To determine whether a low ankle brachial pressure index is associated with an increased risk of cardiovascular events and death, and whether the prediction of such events could be improved by including this index. DESIGN: Cohort study. SETTING: 11 practices in Edinburgh, Scotland. SUBJECTS: 1592 men and women aged 55-74 years selected at random from the age-sex registers of 11 general practices and followed up for 5 years. MAIN OUTCOME MEASURES: Incidence of fatal and non-fatal cardiovascular events and all cause mortality. RESULTS: At baseline 90 (5.7%) of subjects had an ankle brachial pressure index < or = 0.7, 288 (18.2%) had an index < or = 0.9, and 566 (35.6%) < or = 1.0. After five years subjects with an index < or = 0.9 at baseline had an increased risk of non-fatal myocardial infarction (relative risk 1.38, 95% confidence interval 0.88 to 2.16), stroke (1.98, 1.05 to 3.77), cardiovascular death (1.85, 1.15 to 2.97), and all cause mortality (1.58, 1.14 to 2.18) after adjustment for age, sex, coronary disease, and diabetes at baseline. The ability to predict subsequent events was greatly increased by combining the index with other risk factors--for example, hypertensive smokers with normal cholesterol concentrations had a positive predictive value of 25.0%, increasing to 43.8% in subjects with a low index and decreasing to 15.6% in those with a normal index. CONCLUSION: The ankle brachial pressure index is a good predictor of subsequent cardiovascular events, and improves on predictions by conventional risk factors alone. It is simple and accurate and could be included in routine screening of cardiovascular status. PMID:8973232

  4. Brachial-ankle pulse wave velocity as a predictor of mortality in elderly Chinese.

    PubMed

    Sheng, Chang-Sheng; Li, Yan; Li, Li-Hua; Huang, Qi-Fang; Zeng, Wei-Fang; Kang, Yuan-Yuan; Zhang, Lu; Liu, Ming; Wei, Fang-Fei; Li, Ge-Le; Song, Jie; Wang, Shuai; Wang, Ji-Guang

    2014-11-01

    Pulse wave velocity (PWV) is a measure of arterial stiffness and predicts cardiovascular events and mortality in the general population and various patient populations. In the present study, we investigated the predictive value of brachial-ankle PWV for mortality in an elderly Chinese population. Our study subjects were older (≥60 years) persons living in a suburban town of Shanghai. We measured brachial-ankle PWV using an automated cuff device at baseline and collected vital information till June 30, 2013, during follow-up. The 3876 participants (1713 [44.2%] men; mean [±SD] age, 68.1±7.3 years) included 2292 (59.1%) hypertensive patients. PWV was on average 17.8 (±4.0) m/s and was significantly (P<0.0001) associated with age (r=0.48) and in unadjusted analysis with all-cause (n=316), cardiovascular (n=148), stroke (n=46), and noncardiovascular mortality (n=168) during a median follow-up of 5.9 years. In further adjusted analysis, we studied the risk of mortality according to the decile distributions of PWV. Only the subjects in the top decile (23.3-39.3 m/s) had a significantly (P≤0.003) higher risk of all-cause mortality (hazard ratio relative to the whole study population, 1.56; 95% confidence interval, 1.16-2.08), especially in hypertensive patients (hazard ratio, 1.86; 95% confidence interval, 1.31-2.64; P=0.02 for the interaction between PWV and hypertension). Similar trends were observed for cardiovascular, stroke, and noncardiovascular mortality, although statistical significance was not reached (P≥0.08). In conclusion, brachial-ankle PWV predicts mortality in elderly Chinese on the conditions of markedly increased PWV and hypertension. PMID:25259749

  5. Brachial plexus block using lidocaine/epinephrine or lidocaine/xylazine in fat-tailed sheep

    PubMed Central

    Ghadirian, Safoura; Vesal, Nasser

    2013-01-01

    This blinded, randomized experimental study was designed to evaluate the analgesic effects of adding epinephrine or xylazine to lidocaine solution for brachial plexus block (BPB) in sheep. Nine healthy, fat-tailed female lambs (26.6 ± 1.5 kg) were randomly allocated into three groups: lidocaine 2%, 5 mg kg-1 (LID, n = 6), lidocaine (5 mg kg-1) with epinephrine 5 µg mL-1 (LIDEP, n = 6) or lidocaine (5 mg kg-1) with xylazine 0.05 mg kg-1 (LIDXY, n = 6). Each animal was tested twice. The sheep received a total volume of 0.25 mL kg-1 for BPB. A nerve stimulator was used to locate the nerves of the brachial plexus. Onset and duration of analgesia of the forelimb were evaluated using superficial and deep pin prick and pinching of skin with a hemostat clamp. Heart and respiratory rates, and rectal temperature were recorded before and at predetermined intervals following the completion of the block. Brachial administration of LID, LIDEP or LIDXY produced forelimb analgesia within 11.3, 11.0 and 7.0 minutes, respectively. The mean duration of analgesia was 100.0 min in LID and 133.2 min in LIDEP group. The mean duration of analgesia in LIDXY group (186.8 min) was significantly longer compared with LID group. In LIDEP group a significant increase in heart rate occurred 5 min after drug administration. Heart rate decreased from 35 to 80 min in sheep received LIDXY. In conclusion, the addition of xylazine to lidocaine solution for BBP provided a prolonged duration of action without any adverse effects in fat-tailed sheep. PMID:25653791

  6. MR Imaging of Brachial Plexus and Limb-Girdle Muscles in Patients with Amyotrophic Lateral Sclerosis.

    PubMed

    Gerevini, Simonetta; Agosta, Federica; Riva, Nilo; Spinelli, Edoardo G; Pagani, Elisabetta; Caliendo, Giandomenico; Chaabane, Linda; Copetti, Massimiliano; Quattrini, Angelo; Comi, Giancarlo; Falini, Andrea; Filippi, Massimo

    2016-05-01

    Purpose To assess brachial plexus magnetic resonance (MR) imaging features and limb-girdle muscle abnormalities as signs of muscle denervation in patients with amyotrophic lateral sclerosis (ALS). Materials and Methods This study was approved by the local ethical committees on human studies, and written informed consent was obtained from all subjects before enrollment. By using an optimized protocol of brachial plexus MR imaging, brachial plexus and limb-girdle muscle abnormalities were evaluated in 23 patients with ALS and clinical and neurophysiologically active involvement of the upper limbs and were compared with MR images in 12 age-matched healthy individuals. Nerve root and limb-girdle muscle abnormalities were visually evaluated by two experienced observers. A region of interest-based analysis was performed to measure nerve root volume and T2 signal intensity. Measures obtained at visual inspection were analyzed by using the Wald χ(2) test. Mean T2 signal intensity and volume values of the regions of interest were compared between groups by using a hierarchical linear model, accounting for the repeated measurement design. Results The level of interrater agreement was very strong (κ = 0.77-1). T2 hyperintensity and volume alterations of C5, C6, and C7 nerve roots were observed in patients with ALS (P < .001 to .03). Increased T2 signal intensity of nerve roots was associated with faster disease progression (upper-limb Medical Research Council scale progression rate, r = 0.40; 95% confidence interval: 0.001, 0.73). Limb-girdle muscle alterations (ie, T2 signal intensity alteration, edema, atrophy) and fat infiltration also were found, in particular, in the supraspinatus muscle, showing more frequent T2 signal intensity alterations and edema (P = .01) relative to the subscapularis and infraspinatus muscles. Conclusion Increased T2 signal intensity and volume of brachial nerve roots do not exclude a diagnosis of ALS and suggest involvement of the peripheral nervous system in the ALS pathogenetic cascade. MR imaging of the peripheral nervous system and the limb-girdle muscle may be useful for monitoring the evolution of ALS and distinguishing patients with ALS from those with inflammatory neuropathy, respectively. (©) RSNA, 2015. PMID:26583760

  7. Successful management of complex regional pain syndrome type 1 using single injection interscalene brachial plexus block

    PubMed Central

    Fallatah, Summayah M.A.

    2014-01-01

    Complex regional pain syndrome (CRPS) type 1 of the upper limb is a painful and debilitating condition. Interscalene brachial plexus block (ISB) in conjugation with other modalities was shown to be a feasible therapy with variable success. We reported a case of CRPS type 1 as diagnosed by International Association for the Study of Pain criteria in which pharmacological approaches failed to achieve adequate pain relief and even were associated with progressive dysfunction of the upper extremity. Single injection ISB, in combination with physical therapy and botulinum toxin injection, was successful to alleviate pain with functional restoration. PMID:25422619

  8. Brachial artery injury due to closed posterior elbow dislocation: case report☆

    PubMed Central

    Miyazaki, Alberto Naoki; Fregoneze, Marcelo; Santos, Pedro Doneux; do Val Sella, Guilherme; Checchia, Caio Santos; Checchia, Sergio Luiz

    2016-01-01

    An association between closed posterior elbow dislocation and traumatic brachial artery injury is rare. Absence of radial pulse on palpation is an important warning sign and arteriography is the gold-standard diagnostic test. Early diagnosis is essential for appropriate treatment to be provided. This consists of joint reduction and immobilization, along with urgent surgical restoration of arterial flow. Here, a case (novel to the Brazilian literature) of an association between these injuries (and the treatment implemented) in a 27-year-old male patient is reported. These injuries were sustained through physical assault. PMID:27069896

  9. Dehydroepiandrosterone and Corticosterone Are Regulated by Season and Acute Stress in a Wild Songbird: Jugular Versus Brachial Plasma

    PubMed Central

    Newman, Amy E. M.; Pradhan, Devaleena S.; Soma, Kiran K.

    2010-01-01

    Stress has well-known effects on adrenal glucocorticoid secretion, and chronic elevation of glucocorticoids can have detrimental effects on the brain. Dehydroepiandrosterone (DHEA), an androgen precursor synthesized in the adrenal glands or the brain itself, has anti-glucocorticoid properties, but little is known about the role of DHEA in the stress response, particularly in the brain. Here, we measured the effects of acute restraint on circulating corticosterone (CORT) and DHEA levels in wild song sparrows. Blood was collected from either the brachial or jugular vein. In songbirds, jugular plasma is enriched with neurally synthesized steroids, and therefore, jugular plasma is an indirect index of the neural steroidal milieu. Subjects were sampled during four times of year: breeding, molt, early nonbreeding, and mid-nonbreeding. Baseline CORT and DHEA levels showed similar seasonal changes; both steroids were elevated during the breeding season. Baseline CORT and DHEA levels were similar in jugular and brachial plasma. Acute stress had robust effects on CORT and DHEA that were season specific and vein specific. For CORT, during the molt, stress increased jugular CORT more than brachial CORT. For DHEA, during the breeding season, stress decreased jugular DHEA but not brachial DHEA. During the molt, stress increased jugular DHEA but not brachial DHEA. Acute stress did not affect brachial DHEA. These data suggest that acute stress specifically affects the balance between DHEA synthesis and metabolism in the brain. Furthermore, these results suggest that CORT and DHEA are locally synthesized in the brain during molt, when systemic levels of CORT and DHEA are low. PMID:18276756

  10. Thrombin Injection for Treatment of Brachial Artery Pseudoaneurysm at the Site of a Hemodialysis Fistula: Report of Two Patients

    SciTech Connect

    Clark, Timothy W.I.; Abraham, Robert J.

    2000-09-15

    We report two patients with arteriovenous hemodialysis fistulas that were complicated by brachial artery pseudoaneurysms. Each pseudoanerysm was percutaneously thrombosed with an injection of thrombin, using techniques to prevent escape of thrombin into the native brachial artery. In one patient, an angioplasty balloon was inflated across the neck of the aneurysm during thrombin injection. In the second patient, thrombin was injected during ultrasound-guided compression of the neck of the pseudoaneurysm. Complete thrombosis of each pseudoaneurysm was achieved within 30 sec. No ischemic or embolic events occurred. This technique may be useful in treating pseudoaneurysms of smaller peripheral arteries.

  11. 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 responses in microglia in vitro. To extend our in vitro findings in vivo, we investigated whether administration of the peroxisomal proliferator-activated receptor (PPAR)ä agonist, GW0742, prevented radiation-induced brain injury in C57Bl/6 WT mice. Our data demonstrate that GW0742 prevented the radiation-induced increase in the number of activated microglia (CD68+ cells) in wild-type (WT) mice 1 week following 10 Gy WBI. Furthermore, GW0742 inhibited the WBI-induced increase in IL-1β message levels and ERK phosphorylation observed 3 h post-irradiation. In contrast, GW0742 administration failed to modulate the radiation-induced decrease in hippocampal neurogenesis (NeuN+/BrdU+ cells) determined 2 months after irradiation, or mitigate hippocampal-dependent spatial memory impairment observed 3 months post-irradiation using the Barnes Maze task. We used PPARō knockout (KO) mice to examine if the effects of GW0742 are PPARō-dependent. Unexpectedly, PPARō KO mice exhibited a differential response following WBI compared to WT mice; therefore, we were unable to make mechanistic conclusions about GW0742. KO mice do not exhibit a WBI-induced increase in activated microglia; however, they appeared to display a pronounced astrocytic response. In particular, PPARō KO but not WT mice displayed increased GFAP message levels 2 months after WBI. Additionally, the number of GFAP+ cells was reduced significantly in the WT mice 2 months after WBI, but it was not in the PPARō KO mice. These results demonstrate that: i) GW0742 prevents the radiation-induced increase in microglial activation and inflammatory markers, and ii) WT and PPARō KO mice have a differential response to WBI.

  12. 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. PMID:25824410

  13. Gamma radiation induced cell cycle perturbations and DNA damage in Catla Catla as measured by flow cytometry.

    PubMed

    Anbumani, S; Mohankumar, Mary N

    2015-03-01

    Gamma radiation induced cell cycle perturbations and DNA damage in Catla catla were analyzed in erythrocytes at different time points using flow cytometry (FCM). Protracted exposure to radiation induced damage between days 12 and 45. Disturbances in cell cycle machinery, i.e., proportional increase and decrease in Gap0 or quiescent/Gap1 (G0/G1), Synthesis (S) and Gap2/Mitotic (G2/M) phases were observed at both acute and protracted treatments. Both acute and protracted exposures induced apoptosis with a notable significance between days 3 and 6 at protracted and on day 45 at acute doses. Fish exposed protractedly avail some DNA repair mechanisms than acutely exposed. This is the first study to analyze radiation induced DNA damage under laboratory conditions and suggests that flow cytometry can also be an alternate tool to screen genotoxicity induced by ionizing radiation in fish. PMID:25483367

  14. Connecting radiation-induced bystander effects and senescence to improve radiation response prediction.

    PubMed

    Poleszczuk, Jan; Krzywon, Aleksandra; Forys, Urszula; Widel, Maria

    2015-05-01

    For the last two decades radiation-induced bystander effects (RIBEs) have attracted significant attention due to their possible implications for radiotherapy. However, despite extensive research, the molecular pathways associated with RIBEs are still not completely known. In the current study we investigated the role of senescence in the bystander response. Irradiated (2, 4, 6 and 8 Gy) human colorectal carcinoma cells (HCT116) with p53(+/+) (wild-type) or p53(-/-) (knockout) gene were co-incubated with nonirradiated cells of the same type. Clonogenic and senescence assays were used for both irradiated and co-incubated bystander cell populations. We also performed additional measurements on the number of remaining cells after the whole co-incubation period. For radiation doses larger than 2 Gy we observed much larger fractions of senescent cells in p53-positive populations compared to their p53-negative counterparts (15.81% vs. 3.63% in the irradiated population; 2.89% vs. 1.05% in the bystander population; 8 Gy; P < 0.05). Statistically significant differences between cell lines in the clonogenic cell surviving fraction were observed for doses higher than 4 Gy (1.61% for p53(+/+) vs. 0.19% for p53(-/-) in irradiated population; 3.57% for +/+ vs. 50.39% for -/- in bystander population; 8 Gy; P < 0.05). Our main finding was that the number of senescent cells in the irradiated population correlated strongly with the clonogenic cell surviving fraction (R = -0.98, P < 0.001) and the number of senescent cells (R = 0.97, P < 0.001) in the bystander population. We also extended the standard linear-quadratic radiation response model by incorporating the influence of the signals released by the senescent cells, which accurately described the radiation response in the bystander population. Our findings suggest that radiation-induced senescence might be a key player in RIBE, i.e., the strength of RIBE depends on the amount of radiation-induced senescence. PMID:25844948

  15. 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

  16. 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. PMID:25411116

  17. 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.

  18. 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.

  19. 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.

  20. 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

  1. Comparative study of microwave radiation-induced magnetoresistive oscillations induced by circularly- and linearly- polarized photo-excitation.

    PubMed

    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

  2. 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.

  3. Influence of matrix porosity on the immobilization of penicillin acylase by radiation-induced polymerization

    NASA Astrophysics Data System (ADS)

    Carenza, M.; Lora, S.; Palma, G.; Boccù, E.; Largajolli, R.; Veronese, F. M.

    Penicillin acylase was immobilized by low temperature radiation-induced polymerization into polymer matrices obtained from monomers of different hydrophilicities, at various ratios of monomer to enzyme solution and at different polymerization conversions. It was found that the penicillin acylase retention (60-85% of the starting enzyme) is independent of the monomer used in thepolymerization, of the polymerization conversion and of the porosity of the polymer matrix. On the other hand, the penicillin acylase retention strongly depends on the presence in the irradiation mixture of the hydrophobic crosslinking agent, trimethylolpropane trimethacrylate, even in low amounts. The data suggest that the enzyme is bound to the polymer matrix by hydrophobic interactions through crosslinking agent molecules.

  4. 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.

  5. Propagating self-sustained annealing of radiation-induced interstitial complexes

    NASA Astrophysics Data System (ADS)

    Bokov, P. M.; Selyshchev, P. A.

    2016-02-01

    A propagating self-sustained annealing of radiation induced defects as a result of thermal-concentration instability is studied. The defects that are considered in the model are complexes. Each of them consists of one atom of impunity and of one interstitial atom. Crystal with defects has extra energy which is transformed into heat during defect annealing. Simulation of the auto-wave of annealing has been performed. The front and the speed of the auto-wave have been obtained. It is shown that annealing occurs in a narrow region of time and space. There are two kinds of such annealing behaviour. In the first case the speed of the auto-wave oscillates near its constant mean value and the front of temperature oscillates in a complex way. In the second case the speed of propagation is constant and fronts of temperature and concentration look like sigmoid functions.

  6. Ionizing radiation induced leakage current on ultra-thin gate oxides

    SciTech Connect

    Scarpa, A.; Paccagnella, A.; Montera, F.; Ghibaudo, G.; Pananakakis, G.; Fuochi, P.G.

    1997-12-01

    MOS capacitors with a 4.4 nm thick gate oxide have been exposed to {gamma} radiation from a Co{sup 60} source. As a result, the authors have measured a stable leakage current at fields lower than those required for Fowler-Nordheim tunneling. This Radiation Induced Leakage Current (RILC) is similar to the usual Stress Induced Leakage Currents (SILC) observed after electrical stresses of MOS devices. They have verified that these two currents share the same dependence on the oxide field, and the RILC contribution can be normalized to an equivalent injected charge for Constant Current Stresses. They have also considered the dependence of the RILC from the cumulative radiation dose, and from the applied bias during irradiation, suggesting a correlation between RILC and the distribution of trapped holes and neutral levels in the oxide layer.

  7. Radiation induced leakage current and stress induced leakage current in ultra-thin gate oxides

    SciTech Connect

    Ceschia, M.; Paccagnella, A.; Cester, A.; Scarpa, A.; Ghidini, G.

    1998-12-01

    Low-field leakage current has been measured in thin oxides after exposure to ionizing radiation. This Radiation Induced Leakage Current (RILC) can be described as an inelastic tunneling process mediated by neutral traps in the oxide, with an energy loss of about 1 eV. The neutral trap distribution is influenced by the oxide field applied during irradiation, thus indicating that the precursors of the neutral defects are charged, likely being defects associated to trapped holes. The maximum leakage current is found under zero-field condition during irradiation, and it rapidly decreases as the field is enhanced, due to a displacement of the defect distribution across the oxide towards the cathodic interface. The RILC kinetics are linear with the cumulative dose, in contrast with the power law found on electrically stressed devices.

  8. CDK1 enhances mitochondrial bioenergetics for radiation-induced DNA repair

    SciTech Connect

    Qin, Lili; Fan, Ming; Candas, Demet; Jiang, Guochun; Papadopoulos, Stelios; Tian, Lin; Woloschak, Gayle; Grdina, David J.; Li, Jian  Jian

    2015-12-06

    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 the cell-cycle kinase CDK1 and nuclear DNA repair. The basal and radiation-induced mitochondrial ATP generation is reduced significantly in cells harboring CDK1 phosphorylation-deficient mutant complex I subunits. Similarly, mitochondrial ATP generation and nuclear DNA repair are also compromised severely in cells harboring mitochondrially targeted, kinase-deficient CDK1. These findings demonstrate a mechanism governing the communication between mitochondria and the nucleus by which CDK1 boosts mitochondrial bioenergetics to meet the increased cellular fuel demand for DNA repair and cell survival under genotoxic stress conditions.

  9. Percutaneous valve replacement in a young adult for radiation-induced aortic stenosis.

    PubMed

    Latib, Azeem; Montorfano, Matteo; Figini, Filippo; Maisano, Francesco; Chieffo, Alaide; Benussi, Stefano; Bellanca, Raimondo; Gerli, Chiara; Spagnolo, Pietro; Alfieri, Ottavio; Colombo, Antonio

    2012-06-01

    A 46-year-old woman known with relapsing Hodgkin's lymphoma diagnosed at age 5, treated with repeated cycles of radiotherapy and chemotherapy, presented with severe symptomatic radiation-induced aortic stenosis. She also had other late sequelae of radiotherapy including thyroid cancer, mediastinal fribrosis and left pulmonary fibrosis with severe restrictive lung disease and a newly diagnosed renal carcinoma. Due to the prohibitively high surgical risk and need for urgent treatment, she underwent successful transcatheter aortic valve replacement with transfemoral implantation of a 23 mm Edwards SAPIEN-XT prosthesis, which was performed without valvuloplasty of the noncalcified fibrotic valve. The final result was excellent with reduction of the transaortic gradient and no residual aortic regurgitation. PMID:22450861

  10. 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).

  11. Radiation-induced degradation of water pollutants—state of the art

    NASA Astrophysics Data System (ADS)

    Getoff, Nikola

    1996-04-01

    The radiation-induced decomposition of biological resistant pollutants in drinking as well as in wastewater is briefly reviewed. First, some important units, definitions etc., radiation sources, as well as dose-depth curves in water as functions of the electron energy and 60Co-γ-rays are mentioned. Following is a schematical presentation of water radiolysis and of characteristics of primary free radicals. Then the degradation of some aliphatic and aromatic chlorinated compounds in the presence of air is presented. Some spectroscopic and kinetic data of transients resulting from chlorinated phenols are also quoted in order to illustrate and to explain the rather complicated degradation mechanisms. In this respect the synergistic effect of radiation and oxygen as well as that of ozone is also discussed. Finally, a scheme for technical application of high energy electron beam is presented.

  12. 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.

  13. 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

  14. Characterization of radiation induced defects in EUROFER 97 after neutron irradiation

    NASA Astrophysics Data System (ADS)

    Klimenkov, M.; Materna-Morris, E.; Möslang, A.

    2011-10-01

    Specimens of EUROFER 97 prepared for impact tests have been irradiated to an average dose of 16.3 dpa at irradiation temperatures of 250-450 °C. TEM investigations have been performed to study radiation induced changes in the microstructure. The characterization and statistical analysis show the temperature dependant formation of small dislocation loops and He bubbles. The Burgers vector of dislocation loops was ½<1 1 1>. A novel feature is that within statistical uncertainty the maximum in the dislocation density observed around 300 °C decreased with decreasing irradiation temperature down to 250 °C. The TEM data are correlated with tensile and instrumented Charpy test results.

  15. Radiation-induced pemphigus or pemphigoid disease in 3 patients with distinct underlying malignancies.

    PubMed

    Shon, Wonwoo; Wada, David A; Kalaaji, Amer N

    2016-03-01

    The cutaneous lesions of radiation-induced pemphigus or pemphigoid disease may resemble other skin diseases, including recurrent underlying cancer. We performed a computerized search of Mayo Clinic (Rochester, Minnesota) archives and identified 3 cases of pemphigus or pemphigoid disease that occurred after radiation therapy for breast, cervical, and metastatic malignancies, respectively. In 2 of these patients, the disease was initially confined to the irradiated field but subsequently disseminated to other parts of the patients' bodies, including mucosal surfaces. In all 3 patients, the blistering disease occurred 5 to 14 months after the onset of radiation therapy. All 3 were treated with corticosteroids and demonstrated complete recovery of the skin eruption after radiotherapy was discontinued. Although the precise mechanism of this cutaneous eruption is unknown, clinicians should be alert for this potentially serious complication and evaluate all cutaneous eruptions developing during and after radiotherapy. PMID:27023084

  16. Marked reduction of radiation-induced micronuclei in human blood lymphocytes pretreated with melatonin

    SciTech Connect

    Vijayalaxmi; Reiter, R.J.; Leal, B.Z.

    1995-07-01

    Human peripheral blood lymphocytes which were pretreated in vitro with melatonin, and endogenously synthesized pineal hormone, for 20 min at 37 {plus_minus} 1{degrees}C exhibited a significant and concentration-dependent reduction in the frequency of {gamma}radiation-induced micronuclei compared with irradiated cells which did not receive the pretreatment. The extent of the reduction observed with 2.0 mM melatonin was similar to that found in lymphocytes pretreated for 20 min with 1.0 M dimethylsulfoxide, a known free radical scavenger. These observations indicate that melatonin may have an active role in protection of humans against genetic damage due to endogenously produced free radicals, and also may be of use in reducing damage due to exposure to physical and chemical mutagens and carcinogens which generate free radicals. 25 refs., 2 tabs.

  17. Radiation-induced decomposition of trace amounts of 17 β-estradiol in water

    NASA Astrophysics Data System (ADS)

    Kimura, Atsushi; Taguchi, Mitsumasa; Arai, Hidehiko; Hiratsuka, Hiroshi; Namba, Hideki; Kojima, Takuji

    2004-03-01

    The radiation-induced decomposition of trace amounts of 17 β-estradiol (E2) in water was studied as a function of the dose of 60Co γ-rays. The rate constant of the reaction of the OH radicals with E2 was estimated to be 1.6×10 10 mol dm -3 s -1 by a comparison with the known rate constant for the reaction with phenol. Both E2 and E2-equivalent concentrations were estimated by LC-MS and ELISA, and decreased with an increase in γ-rays dose. E2 (1.8 nmol dm -3) in water was degraded almost completely by irradiations up to 10 Gy. The estrogen activity of the same sample solution still remained at a dose of 10 Gy, but decreased at 30 Gy to the lower than the threshold level of contamination to induce some estrogenic effects on the environmental ecology.

  18. 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

  19. Radiation-induced graft polymerization of N-vinylpyrrolidone onto segmented polyurethane based on isophorone diisocyanate

    NASA Astrophysics Data System (ADS)

    Walo, Marta; Przybytniak, Grażyna; Kavaklı, Pınar Akkas; Güven, Olgun

    2013-03-01

    A segmented polyurethane (PUR) sample based on isophorone diisocyante was modified by radiation induced-graft polymerization of N-vinylpyrrolidone. Radiation grafting was carried out by the mutual irradiation method to improve hydrophilicity of the matrix surface. Different parameters affecting the grafting yield, such as effect of dose, monomer and mineral salt concentration, were investigated. It was found that degree of grafting increased with increasing total dose and monomer concentration in the presence of small amount of homopolymer suppressor. Physicochemical properties of the control and grafted PUR were studied using infrared spectroscopy (ATR-FTIR), thermogravimetric analysis, atomic force microscopy and X-ray photoelectron spectroscopy. The wettability was evaluated by contact angle measurements.

  20. Nuclear dynamics of radiation-induced foci in euchromatin and heterochromatin

    SciTech Connect

    Chiolo, Irene; Georgescu, Walter; Tang, Jonathan; Costes, Sylvain V.

    2013-09-03

    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.