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1

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

SciTech Connect

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

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

1989-04-01

2

Brachial plexopathy.  

PubMed

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

Khadilkar, Satish V; Khade, Snehaldatta S

2013-01-01

3

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

SciTech Connect

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.

Olsen, N.K.; Pfeiffer, P.; Johannsen, L.; Schroder, H.; Rose, C. (Odense Univ. Hospital (Denmark))

1993-04-30

4

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

SciTech Connect

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

Amini, Arya [Department of Radiation Oncology, University of Texas M. D. Anderson Cancer Center, Houston, Texas (United States); University of California Irvine School of Medicine, Irvine, California (United States); Yang Jinzhong; Williamson, Ryan [Department of Radiation Physics, University of Texas M. D. Anderson Cancer Center, Houston, Texas (United States); McBurney, Michelle L. [Department of Radiation Oncology, University of Texas M. D. Anderson Cancer Center, Houston, Texas (United States); Erasmus, Jeremy [Department of Diagnostic Imaging, University of Texas M. D. Anderson Cancer Center, Houston, Texas (United States); Allen, Pamela K.; Karhade, Mandar; Komaki, Ritsuko; Liao, Zhongxing; Gomez, Daniel; Cox, James [Department of Radiation Oncology, University of Texas M. D. Anderson Cancer Center, Houston, Texas (United States); Dong, Lei [Department of Radiation Physics, University of Texas M. D. Anderson Cancer Center, Houston, Texas (United States); Welsh, James, E-mail: jwelsh@mdanderson.org [Department of Radiation Oncology, University of Texas M. D. Anderson Cancer Center, Houston, Texas (United States)

2012-03-01

5

Brachial plexopathy: recurrent cancer or radiation  

SciTech Connect

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

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

1984-10-01

6

Myokymia in obstetrically related brachial plexopathy.  

PubMed

Myokymic discharges are spontaneous bursts of semirhythmic potentials that are sometimes correlated with rippling movements of skin and muscle. They have been reported in limb muscles in patients with Guillain-Barré syndrome, spinal stenosis, nerve root and nerve compression, and envenomations. They commonly occur with radiation induced plexopathies (approximately 60% of patients), but have not been reported in obstetrically related brachial plexopathies. We report 2 instances of myokymia in children with obstetric brachial plexus palsies. Each child was studied twice, and it was only at the later study, when the child was 10 or 11 months of age, that these potentials were noted. This could represent ongoing recovery from lesions incurred at birth or developmental changes. The final common pathway of all causes of myokymia could be to generate axonal membrane hyperexcitability. PMID:19078741

Sclar, Gary; Maniker, Allen; Danto, Joseph

2004-06-01

7

Electrophysiology of Brachial and Lumbosacral Plexopathies  

Microsoft Academic Search

Brachial and lumbosacral plexopathies represent a heterogeneous group of disorders including traumatic injury as well as infiltrating\\u000a and inflammatory lesions. The anatomy of both regions is complex, creating challenges in their evaluation; electrophysiological\\u000a testing is a key tool in the assessment of plexopathies. Accurate electrodiagnosis requires a comfortable knowledge of the\\u000a relevant plexus anatomy and applicable nerve conduction techniques, as

Juan A. Acosta; Elizabeth M. Raynor

8

Chronic Brachial Plexopathies and Upper Extremity Proprioception and Strength  

PubMed Central

Brachial plexopathies, where traction or compressive forces disrupt motor and sensory nerve conduction, are the most common nerve injuries in collision sports. Athletes frequently do not report these episodes, however, predisposing the brachial plexus to recurrent trauma. The purpose of this study was to identify how multiple injuries to the brachial plexus affects shoulder strength and proprioception. Ten male intercollegiate football players with at least three unilateral episodes of brachial plexopathies were tested an average of 10 weeks after the most recent episode. The uninvolved shoulder was used as the control. Isometric peak torque was assessed for shoulder abduction, external rotation, and elbow flexion. Proprioception was measured under two conditions: threshold to detection of passive motion and reproduction of passive positioning. Dependent t tests revealed significant mean differences (p < .05) between the involved and uninvolved extremity for abduction peak torque, overall mean peak torque, and one out of four conditions of threshold to detection of passive motion conditions. This was in the neutral position moving into external rotation. In addition, subjects with greater numbers of episodes exhibited larger strength deficits. The results of this study emphasize the need for timely re-evaluation of athletes with chronic brachial plexopathies. ImagesFig 2.Fig 3.Fig 4.Fig 5.

Swanik, C. Buz; Henry, Tim J.; Lephart, Scott M.

1996-01-01

9

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

SciTech Connect

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.

Eblan, Michael J.; Corradetti, Michael N.; Lukens, J. Nicholas; Xanthopoulos, Eric [Department of Radiation Oncology, Abramson Cancer Center, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania (United States)] [Department of Radiation Oncology, Abramson Cancer Center, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania (United States); Mitra, Nandita [Department of Biostatistics and Epidemiology, Abramson Cancer Center, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania (United States)] [Department of Biostatistics and Epidemiology, Abramson Cancer Center, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania (United States); Christodouleas, John P.; Grover, Surbhi; Fernandes, Annemarie T. [Department of Radiation Oncology, Abramson Cancer Center, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania (United States)] [Department of Radiation Oncology, Abramson Cancer Center, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania (United States); Langer, Corey J.; Evans, Tracey L.; Stevenson, James [Department of Medical Oncology, Abramson Cancer Center, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania (United States)] [Department of Medical Oncology, Abramson Cancer Center, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania (United States); Rengan, Ramesh [Department of Radiation Oncology, Abramson Cancer Center, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania (United States)] [Department of Radiation Oncology, Abramson Cancer Center, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania (United States); Apisarnthanarax, Smith, E-mail: apisarns@uphs.upenn.edu [Department of Radiation Oncology, Abramson Cancer Center, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania (United States)] [Department of Radiation Oncology, Abramson Cancer Center, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania (United States)

2013-01-01

10

Upper trunk brachial plexopathy in football players.  

PubMed

Ten football players seen from 1973 through 1977 at the University of Wisconsin Hospitals were found to have clinical and electrodiagnostic evidence of injury to the upper trunk of the brachial plexus. Each had upper limb paresis following one or more blows to the head or shoulders. The development of persistent weakness often was preceded by burning paresthesias in the upper limb. Our experience suggests that the syndrome of burning paresthesias and subsequent arm weakness frequently is secondary to stretching of the brachial plexus. PMID:430686

Robertson, W C; Eichman, P L; Clancy, W G

1979-04-01

11

A Case Report of an Unusual Complication from Bee Sting: Acute Brachial Plexopathy  

PubMed Central

Brachial plexopathy is usually related to trauma like direct injury to the nerve and stretching injuries. Neurological complications following bee sting are uncommon. Here, we describe a rare case of acute brachial plexopathy as a neurological complication following bee sting. A23-year-old maleinitially presented with angioedema and anaphylactic shock one hour after a bee stung at his neck. Twenty four hours after the incidence, he presented with sudden onset of left upper limb weakness. Nerve conduction study and electromyography had shown evidence of left brachial plexopathy.

Fan Kee, Hoo; Hasan, Shariful; Aliaa WS, Wan; B. Basri, Hamidon

2014-01-01

12

Radiation induced lumbosacral plexopathy in gynecologic tumors: Clinical findings and dosimetric analysis  

SciTech Connect

Radiation-induced lumbosacral plexopathy is a rare complication of pelvic irradiation. The authors report four cases among 2,410 patients treated to the pelvis for carcinoma of the cervix and carcinoma of the endometrium. All patients received both external beam and intracavitary radiation. The total calculated dose to the lumbosacral plexus was on the order of 7300 cGy. All 4 cases presented developed lumbosacral plexopathy. Although a few permanent lumbosacral lesions have been reported for patients treated with conventionally fractionated external beam, this syndrome is more often seen in patients treated with intracavitary irradiation for cervical or endometrial carcinoma. 14 refs., 2 figs., 1 tab.

Georgiou, A.; Grigsby, P.W.; Perez, C.A. (Washington School of Medicine, St. Louis, MO (United States))

1993-06-15

13

Radiation induced lumbosacral plexopathy in gynecologic tumors: Clinical findings and dosimetric analysis  

Microsoft Academic Search

Radiation-induced lumbosacral plexopathy is a rare complication of pelvic irradiation. The authors report four cases among 2,410 patients treated to the pelvis for carcinoma of the cervix and carcinoma of the endometrium. All patients received both external beam and intracavitary radiation. The total calculated dose to the lumbosacral plexus was on the order of 7300 cGy. All 4 cases presented

Anastasios Georgiou; Perry W. Grigsby; Carlos A. Perez

1993-01-01

14

[Radiation myelopathy and plexopathy].  

PubMed

Radiation myelopathy (RM) is a relatively rare disorder characterized by white matter lesions of the spinal cord resulting from irradiation. It is divided into two forms by the latent periods: transient RM and delayed RM. The delayed RM develops usually non-transverse myelopathy symptoms such as dissociated sensory disturbance, unilateral leg weakness, and gait disturbance with asymmetric steps. Spinal MRI shows initially cord swelling and long T1/T2 intramedullary lesion with enhancement, then exhibits cord atrophy. Histopathological findings of delayed RM are white matter necrosis, demyelination, venous wall thickening and hyalinization. Glial theory and vascular hypothesis have been proposed to explain its pathophysiology. Several therapies such as adrenocorticosteroid, anticoagulation and hyperbaric oxygen have been tried to this disease with variable benefits. Radiation plexopathy is classified into two major types by the location: radiation-induced brachial plexopathy (BP) and radiation-induced lumbosacral plexopathy (LSP). The BP initially emerges as arm and shoulder pain, whereas LSP as leg weakness. Myokymia and fasciculations are observed in both types. Electrophysiological study reveals findings of peripheral neuropathy. It is often difficult to distinguish the radiation plexopathy from cancer invasion to the plexus, but MRI is useful to differentiate between these diseases. Pathological findings are small vessel obstruction, thick fibrosis, axonal degeneration and demyelination. Its pathomechanism is presumed that radiation-induced fibrous tissue compresses the nerve root as well as microvascular obstruction of the nerve. Adrenocorticosteroid and anticoagulation are considered as the strategy for symptomatic relief. PMID:18306658

Shimazaki, Haruo; Nakano, Imaharu

2008-02-01

15

Plexopathies  

Microsoft Academic Search

The neural plexuses are intricate networks of nerve fibers interposed be- tween the spinal cord or anterior primary rami (APR) proximally and the most proximal portions of peripheral nerves distally. (The term, plexus, means ''interweaving of strands.'') Depending on how they are defined, there are three or four neural plexuses: cervical, brachial, and lumbosacral (also known as pelvic) or lumbar

Asa J. Wilbourn

16

[Post-radiation brachial plexopathy. Persistent conduction block. Myokymic discharges and cramps].  

PubMed

The distinction between radiation and tumor brachial plexopathy may be difficult. The electrophysiological recording of myokymic discharges, frequently present in the former but rare in the latter type of plexopathy, can be helpful for the diagnosis. However, the pathophysiology and the site of origin of these discharges remain unclear. We describe a patient presenting with radiation brachial plexopathy, clinical myokymia, cramps and pain. In this patient, the myokymia--due to abundant myokymic discharges--and the cramps, were related to the existence of persistent conduction block of several years duration. Several findings suggest that the myokymic discharges were generated on blocked axons: voluntary activity did not influence their occurrence nor modify their course; the motor unit potentials involved in the discharges were not evoked by stimulation proximal to the site of the conduction block, whereas the stimulation distal to this site could evoke, modify the rhythm, or interrupt the course of the discharges; the latency of these evoked responses indicated that the site of reflection was proximal on the axon, and likely coincided with that of the conduction block. Recent observations (Roth and Magistris, 1987b) indicated that myokymia, produced by numerous single or grouped fasciculations generated on axon terminals, may be related to persistent conduction blocks of various etiologies. The present case demonstrates that myokymia provoked by myokymic discharges may as well be related to persistent conduction block. The reason why these blocks are accompanied by fasciculations in some situations and by myokymic discharges in others remains an unsolved question. The cramps observed in this patient were also of interest as they occurred in the muscle territory of blocked axons and were provoked by passive muscle shortening. Their origin, distal to the conduction block, is unknown. Finally, a neurolysis did not prevent the progressive transformation of conduction block into axonotmesis. PMID:3368692

Roth, G; Magistris, M R; Le Fort, D; Desjacques, P; Della Santa, D

1988-01-01

17

Brachial plexopathy  

MedlinePLUS

... treated. In some cases, there may be a partial or complete loss of movement or sensation. Nerve ... mild to severe, which can lead to contractures Partial or complete arm paralysis Partial or complete loss ...

18

Brachial Plexopathy due to Myeloid Sarcoma in a Patient With Acute Myeloid Leukemia After Allogenic Peripheral Blood Stem Cell Transplantation  

PubMed Central

Myeloid sarcoma is a solid, extramedullary tumor comprising of immature myeloid cells. It may occur in any organ; however, the invasion of peripheral nervous system is rare. Herein, we report the case of myeloid sarcoma on the brachial plexus. A 37-year-old woman with acute myelogenous leukemia achieved complete remission after chemotherapy. One year later, she presented right shoulder pain, progressive weakness in the right upper extremity and hypesthesia. Based on magnetic resonance images (MRI) and electrophysiologic study, a provisional diagnosis of brachial plexus neuritis was done and hence steroid pulse therapy was carried out. Three months later the patient presented epigastric pain. After upper gastrointestinal endoscopy, myeloid sarcoma of gastrointestinal tract was confirmed pathologically. Moreover, 18-fluoride fluorodeoxyglucose positron emission tomography showed a fusiform shaped mass lesion at the brachial plexus overlapping with previous high signal lesion on the MRI. Therefore, we concluded the final diagnosis as brachial plexopathy due to myeloid sarcoma.

Ha, Yumi; Park, Yoonhong; Kim, Du Hwan

2013-01-01

19

Experimental carcinomatous plexopathy  

Microsoft Academic Search

To understand the pathophysiology of carcinomatous plexopathy better, we studied nerve lesions induced by an experimental thyroid carcinoma implanted over the brachial plexus in 30 Fisher rats. We performed a morphological study including light and electron microscopic examination and teased fibre preparations of brachial plexuses from implanted and control animals. The control side was normal in all. A large tumour

Felipe Vega; Luis Davila; Jean Yves Delattre; Gérard Said; Jacques Vilcoq; Jean Claude Rosenwald; Henri Magdelenat; Michel Poisson

1993-01-01

20

Diagnosis and treatment of lumbosacral plexopathies in patients with cancer  

SciTech Connect

Eleven patients were diagnosed as having lumbosacral plexopathy at M. D. Anderson Hospital, Houston, from August 1981 through July 1982. Four causes were documented: plexopathy secondary to metastatic disease (six cases); radiation-induced plexopathy (two cases); plexopathy secondary to intra-arterial chemotherapy (two cases); and plexopathy as the result of a second primary tumor (one case). Patients with plexopathies secondary to tumor or irradiation complained of pain in the ipsilateral lower extremity. Computed tomography of the pelvis was the most accurate method of documenting tumor in the region of the lumbosacral plexus. Radiation therapy records of patients with cervical carcinoma were reviewed with respect to positioning of intracavitary radium, which was thought to be responsible for the development of radiation-induced plexopathies. Radiation therapy and/or systemic chemotherapy provided relief of pain and improvement of neurologic deficits in three patients with metastatic involvement.

Pettigrew, L.C.; Glass, J.P.; Maor, M.; Zornoza, J.

1984-12-01

21

Diagnosis of brachial and lumbosacral plexus lesions.  

PubMed

To most doctors, brachial and lumbosacral plexopathies are known as difficult disorders, because of their complicated anatomy and relatively rare occurrence. Both the brachial, lumbar, and sacral plexuses are extensive PNS structures stretching from the neck to axillary region and running in the paraspinal lumbar and pelvic region, containing 100000-200000 axons with 12-15 major terminal branches supplying almost 50 muscles in each limb. The most difficult part in diagnosing a plexopathy is probably that it requires an adequate amount of clinical suspicion combined with a thorough anatomical knowledge of the PNS and a meticulous clinical examination. Once a set of symptoms is recognized as a plexopathy the patients' history and course of the disorder will often greatly limit the differential diagnosis. The most common cause of brachial plexopathy is probably neuralgic amyotrophy and the most common cause of lumbosacral plexopathy is diabetic amyotrophy. Traumatic and malignant lesions are fortunately rarer but just as devastating. This chapter provides an overview of both common and rarer brachial and lumbosacral plexus disorders, focusing on clinical examination, the use of additional investigative techniques, prognosis, and treatment. PMID:23931788

van Alfen, Nens; Malessy, Martijn J A

2013-01-01

22

Fecal incontinence after pelvic radiotherapy: Evidences for a lumbosacral plexopathy  

Microsoft Academic Search

PURPOSE: Clinical manifestations of radiation-induced lumbosacral plexopathy remain a rare event. We report the case of a 62-year-old woman with neurogenic fecal incontinence that occurred after radiotherapy of cervical carcinoma. METHODS: Anorectal, bladder, and lower limb sensory-motor functions, as biologic and morphologic explorations, were performed on repeated occasions. RESULTS: Anorectal manometry, conduction times of pudendal nerves, sacral latencies, and pudendal

Franck Iglicki; Benoit Coffin; Olivier Ille; Bernard Flourié; Gérard Amarenco; Marc Lémann; Bernard Messing

1996-01-01

23

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

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.

Yi, Sun K., E-mail: sun.yi@ucdmc.ucdavis.edu [Department of Radiation Oncology, University of California, Davis Cancer Center, Sacramento, CA (United States); Mak, Walter [Department of Radiology, University of California, Davis Medical Center, Sacramento, CA (United States)] [Department of Radiology, University of California, Davis Medical Center, Sacramento, CA (United States); Yang, Claus C.; Liu Tianxiao [Department of Radiation Oncology, University of Mississippi Medical Center, Jackson, MS (United States)] [Department of Radiation Oncology, University of Mississippi Medical Center, Jackson, MS (United States); Cui Jing; Chen, Allen M.; Purdy, James A.; Monjazeb, Arta M. [Department of Radiation Oncology, University of California, Davis Cancer Center, Sacramento, CA (United States)] [Department of Radiation Oncology, University of California, Davis Cancer Center, Sacramento, CA (United States); Do, Ly [Cancer Care Institute, San Jose, CA (United States)] [Cancer Care Institute, San Jose, CA (United States)

2012-10-01

24

Brachial and lumbar neuropathies.  

PubMed

Sporadic acute brachial plexus neuropathy occurs in approximately 1.64/100,000 population, but may present in epidemic form. Sporadic lumbosacral plexus neuropathy is far less common and has to be distinguished from more common disorders affecting the plexus and roots such as diabetes. Early this century, when serum therapy became popular to treat or prevent prevalent infectious diseases, it became apparent that a plexopathy could follow treatment. It has thus been assumed that many of the cases are due to an autoimmune or inflammatory lesion of the plexus. A wide variety of vaccines, infections and medications seem able to precipitate the disorder. Recent work has shown that cultured lymphocytes from affected patients, but not controls, are able to mount a blastogenic response to components of cadaver brachial plexus. This response seems to be selective not only to the brachial plexus, but also to discrete components of the plexus. The recovery rate in brachial plexus neuropathy is good, being almost 90% at 3 years. Recovery with lumbosacral disease is less satisfactory. Histological material and descriptions of acute brachial plexus neuropathy are rare. There is some evidence that an inflammatory process is present, but the role of demyelination and axonal atrophy in producing the observed clinical signs, is still uncertain. Virtually nothing is known about the histological changes in lumbosacral plexus neuropathy. Treatment is mainly supportive, but important in limiting disability. Steroids may help relieve pain in the acute stages, but do not seem to alter the prognosis. PMID:7921588

Russell, J W; Windebank, A J

1994-04-01

25

[Radiation-induced neuropathy].  

PubMed

Radiation-induced neuropathy is commonly observed among oncological patients. Radiation can affect the nervous tissue directly or indirectly by inducing vasculopathy or dysfunction of internal organs. Symptoms may be mild and reversible (e.g., pain, nausea, vomiting, fever, drowsiness, fatigue, paresthesia) or life-threatening (cerebral oedema, increased intracranial pressure, seizures). Such complications are clinically divided into peripheral (plexopathies, neuropathies of spinal and cranial nerves) and central neuropathy (myelopathy, encephalopathy, cognitive impairment). The degree of neuronal damages primarily depends on the total and fractional radiation dose and applied therapeutic methods. The conformal and megavoltage radiotherapy seems to be the safeties ones. Diagnostic protocol includes physical examination, imaging (in particular magnetic resonance), electromyography, nerve conduction study and sometimes histological examination. Prevention and early detection of neurological complications are necessary in order to prevent a permanent dysfunction of the nervous system. Presently their treatment is mostly symptomatic, but in same cases a surgical intervention is required. An experimental and clinical data indicates some effectiveness of different neuroprotective agents (e.g. anticoagulants, vitamin E, hyperbaric oxygen, pentoxifylline, bevacizumab, methylphenidate, donepezil), which should be administered before and/or during radiotherapy. PMID:24490474

Kolak, Agnieszka; Staros?awska, Elzbieta; Kieszko, Dariusz; Cisek, Pawe?; Patyra, Krzysztof Ireneusz; Surdyka, Dariusz; Dobrzy?ska-Rutkowska, Aneta; ?opacka-Szatan, Karolina; Burdan, Franciszek

2013-12-01

26

Bilateral brachial plexopathy complicating Henoch–Schönlein purpura  

Microsoft Academic Search

An 11-year-old boy presented with convulsion, fever, rash, abdominal pain, swelling on the eyelids, elbow and wrists, oliguria and hematuria. Based on the abnormal findings the patient was diagnosed with Henoch-Schönlein purpura. On the 3rd day of admission, neurological examination showed ataxic gait, loss of deep tendon reflexes, and decreased (4\\/5) of muscle strength on all extremities. Additionally, bilateral loss

Cahide Y?lmaz; Hüseyin Çaksen; ?ükrü Arslan; Ömer Anlar; Bülent Ata?; Ahmet Sami Güven; Dursun Odaba?

2006-01-01

27

Brachial plexus  

MedlinePLUS

The brachial plexus is a group of nerves that run from the lower neck through the upper shoulder area. These ... Damage to the brachial plexus nerves can cause muscle and sensation problems that are often associated with pain in the same area. Symptoms may ...

28

Lumbosacral plexus injury and brachial plexus injury following prolonged compression.  

PubMed

We report the case of a 36-year-old woman who developed right upper and lower limb paralysis with sensory deficit after sedative drug overdose with prolonged immobilization. Due to the initial motor and sensory deficit pattern, brachial plexus injury or C8/T1 radiculopathy was suspected. Subsequent nerve conduction study/electromyography proved the lesion level to be brachial plexus. Painful swelling of the right buttock was suggestive of gluteal compartment syndrome. Elevation of serum creatine phosphokinase and urinary occult blood indicated rhabdomyolysis. The patient received medical treatment and rehabilitation; 2 years after the injury, her right upper and lower limb function had recovered nearly completely. As it is easy to develop complications such as muscle atrophy and joint contracture during the paralytic period of brachial plexopathy and lumbosacral plexopathy, early intervention with rehabilitation is necessary to ensure that the future limb function of the patient can be recovered. Our patient had suspected gluteal compartment syndrome that developed after prolonged compression, with the complication of concomitant lumbosacral plexus injury and brachial plexus injury, which is rarely reported in the literature. A satisfactory outcome was achieved with nonsurgical management. PMID:17116618

Kao, Chung-Lan; Yuan, Chia-Hei; Cheng, Yuan-Yang; Chan, Rai-Chi

2006-11-01

29

Brachial plexus lesions after backpack carriage in young adults.  

PubMed

Carrying a heavy backpack exerts compression on shoulders, with the potential to cause brachial plexopathy. We evaluated the incidence and predisposing factors of compression plexopathy of the shoulder region in 152,095 military conscripts, hypothesizing that a low body mass index and poor physical fitness predispose to the plexus lesion. Reports of conscripts with neural lesions of the upper arm associated with load carriage were reviewed retrospectively for details associated with the condition onset, symptoms, signs, nerve conduction studies, and electromyographic examinations. Height, weight, and physical fitness scores were obtained from their military training data. The incidence of neural compression after shoulder load carriage in Finnish soldiers was 53.7 (95% confidence interval, 39.5-67.8) per 100,000 conscripts per year. The long thoracic nerve was affected in 19, the axillary nerve in 13, the suprascapular nerve in seven, and the musculocutaneous nerve in six patients. Four patients (7%) had hereditary neuropathy with susceptibility to pressure palsies (HNPP). Symptoms were induced by lighter loads in patients with HNPP. Vulnerability to brachial plexopathy was not predictable from body structure or physical fitness level. To prevent these lesions, awareness of the condition and its symptoms should be increased and backpack designs should be improved. PMID:16906084

Mäkelä, Jyrki P; Ramstad, Raimo; Mattila, Ville; Pihlajamäki, Harri

2006-11-01

30

Constraining the brachial plexus does not compromise regional control in oropharyngeal carcinoma  

PubMed Central

Background Accumulating evidence suggests that brachial plexopathy following head and neck cancer radiotherapy may be underreported and that this toxicity is associated with a dose–response. Our purpose was to determine whether the dose to the brachial plexus (BP) can be constrained, without compromising regional control. Methods The radiation plans of 324 patients with oropharyngeal carcinoma (OPC) treated with intensity-modulated radiation therapy (IMRT) were reviewed. We identified 42 patients (13%) with gross nodal disease <1 cm from the BP. Normal tissue constraints included a maximum dose of 66 Gy and a D05 of 60 Gy for the BP. These criteria took precedence over planning target volume (PTV) coverage of nodal disease near the BP. Results There was only one regional failure in the vicinity of the BP, salvaged with neck dissection (ND) and regional re-irradiation. There have been no reported episodes of brachial plexopathy to date. Conclusions In combined-modality therapy, including ND as salvage, regional control did not appear to be compromised by constraining the dose to the BP. This approach may improve the therapeutic ratio by reducing the long-term risk of brachial plexopathy.

2013-01-01

31

CT of the brachial plexus in patients with cancer  

SciTech Connect

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.

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

1983-12-01

32

Brachial Plexus Injuries  

MedlinePLUS

NINDS Brachial Plexus Injuries Information Page Synonym(s): Erb's Palsy Table of Contents (click to jump to sections) What are Brachial ... is being done? Clinical Trials Organizations What are Brachial Plexus Injuries? The brachial plexus is a network of ...

33

Lumbar plexopathy after radical nephrectomy -A case report-  

PubMed Central

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.

Lee, Young-Bok; Jeong, Eui-Kyun

2012-01-01

34

Sonographic evaluation of brachial plexus pathology.  

PubMed

Pre-operative US examinations of the brachial plexus were performed with the purpose of exploring the potential of this technique in recognizing lesions in the region and defining their sonographic morphology, site, extent, and relations to adjacent anatomic structures, and comparing them to the surgical findings to obtain maximal confirmation. Twenty-eight patients with clinical, electro-conductive, and imaging findings suggestive of brachial plexus pathology were included in this study. There were four main etiology groups: post-traumatic brachial plexopathies; primary tumors (benign and malignant); secondary tumors; and post irradiation injuries. Twenty-one of the 28 patients underwent surgery. Advanced imaging (mostly MRI) served as an alternative gold standard for confirmation of the findings in the non-surgically treated group of patients. The US examinations were performed with conventional US units operating at 5- to 10-MHz frequencies. The nerves were initially localized at the level of the vertebral foramina and then were followed longitudinally and axially down to the axillary region. Abnormal US findings were detected in 20 of 28 patients. Disruption of nerve continuity and focal scar tissue masses were the principal findings in the post-traumatic cases. Focal masses within a nerve or adjacent to it and diffuse thickening of the nerve were the findings in primary and secondary tumors. Post-irradiation changes presented as nerve thickening. Color Doppler was useful in detecting internal vascularization within masses and relation of a mass to adjacent vessels. The eight sonographically negative cases consisted either of traumatic neuromas smaller than 12 mm in size and located in relatively small branches of posterior location or due to fibrotic changes of diffuse nature. Sonography succeeded in depicting a spectrum of lesions of traumatic, neoplastic, and inflammatory nature in the brachial plexus. It provided useful information regarding the lesion site, extent, and anatomic relationships; thus, the principal aims of the study were therefore met. Once the technique of examination is mastered, sonography should be recommended as part of the pre-operative evaluation process post-ganglionic brachial plexus pathology. Most disadvantages are related to the restricted field of view and inability to overcome bonny obstacles particularly in evaluating pre-ganglionic region. As sonography is frequently employed for investigation of the supraclavicular region, awareness of the radiologist to the findings described may enable the early recognition of pathologies involving or threatening to involve the brachial plexus. PMID:12845468

Graif, Moshe; Martinoli, Carlo; Rochkind, Shimon; Blank, Anat; Trejo, Leonor; Weiss, Judith; Kessler, Ada; Derchi, Lorenzo E

2004-02-01

35

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

PubMed Central

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.

Kosobucki, Radoslaw; Luczynska, Elzbieta; Bieda, Tomasz; Urbanski, Krzysztof

2012-01-01

36

Brachial plexus (image)  

MedlinePLUS

The brachial plexus is a group of nerves that originate from the neck region and branch off to give rise ... movement in the upper limb. Injuries to the brachial plexus are common and can be debilitating. If the ...

37

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, ...

38

Radiation-induced gliomas  

PubMed Central

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

Prasad, Gautam; Haas-Kogan, Daphne A.

2013-01-01

39

Radiation-induced pneumothorax  

SciTech Connect

Pneumothorax is an uncommon complication of radiation therapy to the chest. The proposed pathogenesis is radiation-induced fibrosis promoting subpleural bleb formation that ruptures resulting in pneumothorax. We report on two young patients with primary sarcomas without pulmonary metastases who developed spontaneous pneumothorax after irradiation. Neither patient had antecedent radiographic evidence of pulmonary fibrosis.

Epstein, D.M.; Littman, P.; Gefter, W.B.; Miller, W.T.; Raney, R.B. Jr.

1983-01-01

40

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

PubMed Central

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.

Anson, Jonathan A; McQuillan, Patrick M

2014-01-01

41

Use of intercostal nerves for different target neurotization in brachial plexus reconstruction  

PubMed Central

Intercostal nerve transfer is a valuable procedure in devastating plexopathies. Intercostal nerves are a very good choice for elbow flexion or extension and shoulder abduction when the intraplexus donor nerves are not available. The best results are obtained in obstetric brachial plexus palsy patients, when direct nerve transfer is performed within six months from the injury. Unlike the adult posttraumatic patients after median and ulnar nerve neurotization with intercostal nerves, almost all obstetric brachial plexus palsy patients achieve protective sensation in the hand and some of them achieve active wrist and finger flexion. Use in combination with proper muscles, intercostal nerve transfer can yield adequate power to the paretic upper limb. Reinnervation of native muscles (i.e., latissimus dorsi) should always be sought as they can successfully be transferred later on for further functional restoration.

Lykissas, Marios G; Kostas-Agnantis, Ioannis P; Korompilias, Ananstasios V; Vekris, Marios D; Beris, Alexandros E

2013-01-01

42

[Radiation induced side effects].  

PubMed

More than half of all people with cancer are treated with radiation therapy. Over the last decade the technical advances, both in therapy beam precision and imaging, have greatly improved the therapeutic ratio and accuracy of modern radiotherapy. However, damaging healthy tissues near the tumor leads to radiation induced injury that develops immediately and continue to progress long after exposure to radiation. Recently dramatic advances have been made in understanding the determinant of tissue response to radiation exposure. PMID:22641879

Henni, Mehdi; Ali, David

2012-04-01

43

The Brachial Plexus  

NSDL National Science Digital Library

This project is designed to instruct students on the basic anatomy and physiology of the brachial plexus. Through exercises such as matching, coloring and labeling, students are introduced to the brachial plexus and its role in controlling the cutaneous sensation and movement of the upper limbs.

Mr. Samuel J Schwarzlose (Amarillo College Biology)

2010-08-20

44

Radiation-induced malignant and atypical peripheral nerve sheath tumors  

SciTech Connect

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.

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

1980-04-01

45

Differential diagnosis between radiation and tumor plexopathy of the pelvis  

SciTech Connect

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

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

1985-01-01

46

Radiation-Induced Bioradicals  

NASA Astrophysics Data System (ADS)

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.

Lahorte, Philippe; Mondelaers, Wim

47

The Ankle Brachial Index  

Microsoft Academic Search

\\u000a The ankle brachial index (ABI) is defined as the ratio of systolic blood pressures in the ankles to that in the arms. The\\u000a arteries typically interrogated for calculating the ABI include the brachial arteries in the arms and the posterior tibial\\u000a and\\/or dorsalis pedis arteries in the legs. Owing to physiologic considerations, the ratio of the pressures in the ankles

Matthew A. Allison; Mary M. McDermott

48

Neurotization from two medial pectoral nerves to musculocutaneous nerve in a pediatric brachial plexus injury.  

PubMed

Traumatic brachial plexus injuries can be devastating, causing partial to total denervation of the muscles of the upper extremities. Surgical reconstruction can restore motor and/or sensory function following nerve injuries. Direct nerve-to-nerve transfers can provide a closer nerve source to the target muscle, thereby enhancing the quality and rate of recovery. Restoration of elbow flexion is the primary goal for patients with brachial plexus injuries. A 4-year-old right-hand-dominant male sustained a fracture of the left scapula in a car accident. He was treated conservatively. After the accident, he presented with motor weakness of the left upper extremity. Shoulder abduction was grade 3 and elbow flexor was grade 0. Hand function was intact. Nerve conduction studies and an electromyogram were performed, which revealed left lateral and posterior cord brachial plexopathy with axonotmesis. He was admitted to Rehabilitation Medicine and treated. However, marked neurological dysfunction in the left upper extremity was still observed. Six months after trauma, under general anesthesia with the patient in the supine position, the brachial plexus was explored through infraclavicular and supraclavicular incisions. Each terminal branch was confirmed by electrophysiology. Avulsion of the C5 roots and absence of usable stump proximally were confirmed intraoperatively. Under a microscope, neurotization from the musculocutaneous nerve to two medial pectoral nerves was performed with nylon 8-0. Physical treatment and electrostimulation started 2 weeks postoperatively. At a 3-month postoperative visit, evidence of reinnervation of the elbow flexors was observed. At his last follow-up, 2 years following trauma, the patient had recovered Medical Research Council (MRC) grade 4+ elbow flexors. We propose that neurotization from medial pectoral nerves to musculocutaneous nerve can be used successfully to restore elbow flexion in patients with brachial plexus injuries. PMID:23115676

Yu, Dong-Woo; Kim, Min-Su; Jung, Young-Jin; Kim, Seong-Ho

2012-09-01

49

Neurotization from Two Medial Pectoral Nerves to Musculocutaneous Nerve in a Pediatric Brachial Plexus Injury  

PubMed Central

Traumatic brachial plexus injuries can be devastating, causing partial to total denervation of the muscles of the upper extremities. Surgical reconstruction can restore motor and/or sensory function following nerve injuries. Direct nerve-to-nerve transfers can provide a closer nerve source to the target muscle, thereby enhancing the quality and rate of recovery. Restoration of elbow flexion is the primary goal for patients with brachial plexus injuries. A 4-year-old right-hand-dominant male sustained a fracture of the left scapula in a car accident. He was treated conservatively. After the accident, he presented with motor weakness of the left upper extremity. Shoulder abduction was grade 3 and elbow flexor was grade 0. Hand function was intact. Nerve conduction studies and an electromyogram were performed, which revealed left lateral and posterior cord brachial plexopathy with axonotmesis. He was admitted to Rehabilitation Medicine and treated. However, marked neurological dysfunction in the left upper extremity was still observed. Six months after trauma, under general anesthesia with the patient in the supine position, the brachial plexus was explored through infraclavicular and supraclavicular incisions. Each terminal branch was confirmed by electrophysiology. Avulsion of the C5 roots and absence of usable stump proximally were confirmed intraoperatively. Under a microscope, neurotization from the musculocutaneous nerve to two medial pectoral nerves was performed with nylon 8-0. Physical treatment and electrostimulation started 2 weeks postoperatively. At a 3-month postoperative visit, evidence of reinnervation of the elbow flexors was observed. At his last follow-up, 2 years following trauma, the patient had recovered Medical Research Council (MRC) grade 4+ elbow flexors. We propose that neurotization from medial pectoral nerves to musculocutaneous nerve can be used successfully to restore elbow flexion in patients with brachial plexus injuries.

Yu, Dong-Woo; Kim, Min-Su; Jung, Young-Jin

2012-01-01

50

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

PubMed

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

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

2013-01-01

51

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

PubMed Central

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.

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

2013-01-01

52

Perinatal brachial plexus palsy  

PubMed Central

BACKGROUND Perinatal brachial plexus palsy (PBPP) is a flaccid paralysis of the arm at birth that affects different nerves of the brachial plexus supplied by C5 to T1 in 0.42 to 5.1 infants per 1000 live births. OBJECTIVES To identify antenatal factors associated with PBPP and possible preventive measures, and to review the natural history as compared with the outcome after primary or secondary surgical interventions. METHODS A literature search on randomized controlled trials, systematic reviews and meta-analyses on the prevention and treatment of PBPP was performed. EMBASE, Medline, CINAHL and the Cochrane Library were searched until June 2005. Key words for searches included ‘brachial plexus’, ‘brachial plexus neuropathy’, ‘brachial plexus injury’, ‘birth injury’ and ‘paralysis, obstetric’. RESULTS There were no prospective studies on the cause or prevention of PBPP. Whereas birth trauma is said to be the most common cause, there is some evidence that PBPP may occur before delivery. Shoulder dystocia and PBPP are largely unpredictable, although associations of PBPP with shoulder dystocia, infants who are large for gestational age, maternal diabetes and instrumental delivery have been reported. The various forms of PBPP, clinical findings and diagnostic measures are described. Recent evidence suggests that the natural history of PBPP is not all favourable, and residual deficits are estimated at 20% to 30%, in contrast with the previous optimistic view of full recovery in greater than 90% of affected children. There were no randomized controlled trials on nonoperative management. There was no conclusive evidence that primary surgical exploration of the brachial plexus supercedes conservative management for improved outcome. However, results from nonrandomized studies indicated that children with severe injuries do better with surgical repair. Secondary surgical reconstructions were inferior to primary intervention, but could still improve arm function in children with serious impairments. CONCLUSIONS It is not possible to predict which infants are at risk for PBPP, and therefore amenable to preventive measures. Twenty-five per cent of affected infants will experience permanent impairment and injury. If recovery is incomplete by the end of the first month, referral to a multidisciplinary team is necessary. Further research into prediction, prevention and best mode of treatment needs to be done.

Andersen, John; Watt, Joe; Olson, Jaret; Van Aerde, John

2006-01-01

53

Intravenous immunoglobulin therapy for idiopathic postoperative lumbosacral plexopathy.  

PubMed

We report a patient who developed an acute lumbosacral plexopathy (LSP) following spinal surgery on lumbos segments. He recovered dramatically following treatment with high-dose intravenous immunoglobulin (IVIg). A 66-year-old man who underwent an L4 to S1 decompressive laminectomy required re-admission after developing contralateral leg pain. Follow-up lumbosacral magnetic resonance imaging showed only mild postoperative changes. Ten days after re-admission, he developed relatively rapid onset ipsilateral inguinal pain and weakness of all his leg muscles with diminished sensation in a lumbosacral plexus distribution. Re-exploration revealed no specific lesion except for adhesions and resulted in no improvement. Following treatment with IVIg (0.4 g/kg daily) for five days, he showed dramatic resolution of motor weakness and pain. There has been no relapse following six months follow-up. Although IVIg treatment does not guarantee a positive response in all types of LSP, it should be considered for severe, rapidly progressive and even for postoperative cases. PMID:15851092

Park, Dong-Hyuk; Park, Youn-Kwan; Kim, Joo-Han

2005-04-01

54

Management of brachial plexus injuries  

Microsoft Academic Search

Most brachial plexus lesions are traction injuries sustained during birth, but in adolescents and older people they are usually\\u000a caused by traffic accidents or following a fall in the home. A minority are the result of penetrating injury after civilian\\u000a assault or trauma encountered during wartime.\\u000a \\u000a Birth palsy cases (obstetric brachial plexus palsy) and the remaining cases (traumatic brachial plexus

G. Blaauw; R. S. Muhlig; J. W. Vredeveld

55

Radiation-induced peritoneal mesothelioma  

Microsoft Academic Search

A case report of a patient who developed peritoneal mesothelioma 7 years after internal and external irradiation for carcinoma of the cervix is reported. No previous reports of induction of this tumor by irradiation have been found. The subject of radiation-induced tumors and peritoneal mesothelioma is briefly discussed.

Terence L. Babcock; Darryl H. Powell; Roger S. Bothwell

1976-01-01

56

Radiation-induced intracranial fibrochondrosarcoma.  

PubMed

A 50-year-old patient developed a left temporal fibrochondrosarcoma 27 years after radiation therapy for a suspected pituitary adenoma. The long latency between the irradiation and the development of the sarcoma and the histological nature of the tumour are unusual features for a malignant radiation-induced intracranial tumour. The histogenesis of fibrochondrosarcoma of the brain is discussed. PMID:3772411

Pagès, A; Pagès, M; Ramos, J; Bénézech, J

1986-10-01

57

Postpartum lumbosacral plexopathy limited to autonomic and perineal manifestations: clinical and electrophysiological study of 19 patients  

Microsoft Academic Search

The objective was to describe perineal electrophysiological findings and to determine their diagnostic value in a type of lumbosacral plexopathy after vaginal delivery, which only involves the lower part of the plexus (S2-S4). Consecutive female patients referred to an outpatients' urodynamic clinic were the source. Nineteen previously healthy women, 13 multiparae and six para 1, were investigated. Mean age was

Samer Sheikh Ismael; Gerard Amarenco; Béatrice Bayle; Jacques Kerdraon

2000-01-01

58

Radiation–Induced Haemorrhagic Cystitis  

Microsoft Academic Search

Objectives: In this article we review the literature concerning the frequency and management of severe haemorrhagic radiation–induced cystitis.Methods: A Medline search was performed from 1966 to 1999 for articles in English. A total of 309 references were found. Abstracts and complete articles were reviewed.Results: Severe haemorrhagic cystitis following radiotherapy remains a relatively rare event. However, the fact that it is

Jeremy P. Crew; Catherine R. Jephcott; John M. Reynard

2001-01-01

59

[Perinatal brachial plexus palsy].  

PubMed

Upper limbs palsy as a result of affliction of plexus brachialis nervous bunch is disorder, whose frequency moves among 0.42-5.1 / 1000 liveborn children. Delivery mechanism itself certain weighty, no however only cause rising paralysis. Some way paralysis rise already intrauterinne, some way then at surgical childbirth per sectionem caeseream. Brachial plexus palsy isn't benign disorder. If isn't this disorder in time diagnosed and accordingly treated, child threatens late aftermath, especially significant limitation of limbs movement with functional consequencies. PMID:20925223

Macko, Jozef

2010-08-01

60

[A case of a postmedian sternotomy C8 plexopathy localized with electrodiagnostic tests].  

PubMed

A postmedian sternotomy plexopathy is a C8 plexopathy following an operation that requires a median sternotomy, in which the C8 anterior primary ramus is injured. Since the clinical picture of a C8 plexopathy is quite similar to an ulnar neuropathy, electrodiagnostic tests are crucial for localizing the lesion and confirming the diagnosis. This is the first published report in Japan that shows the clinical picture of a postmedian sternotomy C8 plexopathy and the utility of electrophysiological tests to diagnose this disease. A 54 year-old man developed numbness in the right ring and little fingers just after an operation through a median sternotomy to treat an aortic dissection. His symptoms did not improve and he was reevaluated 11 months after the operation. Neurological examinations revealed a weakness of the right ulnar-innervated hand muscles, and tingling dysesthesia of the ring and little fingers. In electrodiagnostic tests, the ulnar SNAP was severely depressed on the affected side, and in addition the amplitude of the median SNAP over the ring finger (Med-D4) was also reduced by more than half of that observed in his healthy side (62% side-to-side difference). In our investigation of 26 control subjects, the side-to-side difference of the Med-D4 SNAP amplitude did not exceed 50% for any subject. Needle electromyography revealed profuse denervation activities in the FCU, ADM and EPB, and moderately reduced recruitment and giant motor unit potentials in the EI. The postmedian sternotomy plexopathy had been long described, but its precise localization using modern electrodiagnostic techniques has been presented only recently in the literature. Our results are largely the same as those found in previous reports, which show the predominant involvement of the ulnar sensory and motor fibers and electromyographic changes in C8-radial muscles (EPB and EI). Furthermore, the antidromic SNAP of Med-D4 was significantly reduced in amplitude on the affected side, and supported the diagnosis of the C8 plexopathy. The Med-D4 method is the only method that can document a nonulnar C8 involvement solely by NCS. Whereas the potential role of the Med-D4 method has been suggested in this condition, this is the first report that actually showed its utility. PMID:17511287

Higashihara, Mana; Sonoo, Masahiro; Hashida, Hideji; Unno, Satoko; Takeda, Katsuhiko

2007-04-01

61

Axillary Brachial Plexus Block  

PubMed Central

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.

Satapathy, Ashish R.; Coventry, David M.

2011-01-01

62

Axillary brachial plexus block.  

PubMed

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

Satapathy, Ashish R; Coventry, David M

2011-01-01

63

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 ...

64

Radiation-Induced Grafting on Polyamides.  

National Technical Information Service (NTIS)

The objective of the project was to investigate radiation-induced grafting on polyamides, with emphasis on fluorine-containg vinyl monomers. The principal experimental technique was the gamma ray irradiation of polyamide film samples immersed in suitable ...

J. E. Wilson

1972-01-01

65

Bilateral ischemic lumbosacral plexopathy from chronic aortoiliac occlusion presenting with progressive paraplegia.  

PubMed

Spinal cord ischemia is rare but causes significant morbidity and mortality. Spinal cord ischemia has been reported after open and endovascular interventions of the thoracic and abdominal aorta, and, rarely, acute occlusion of aorta from in situ thrombosis or acute embolic occlusion. Acute interruption of the critical blood supply to the spinal cord or root contributes to this devastating neurologic deficit. However, gradually worsening lumbosacral plexopathy and consequent paraplegia related to chronic aortic occlusion is extremely rare. We present a case of a 58-year-old man with progressive lower limb paralysis from atherosclerotic aortoiliac occlusion without history of aortic surgery or evidence of thromboembolism. PMID:23726871

Kim, Hyangkyoung; Kang, Si Hyun; Kim, Don-Kyu; Seo, Kyung Mook; Kim, Tha Joo; Hong, Joonhwa

2014-01-01

66

Lumbar Plexopathy Caused by Metastatic Tumor, Which Was Mistaken for Postoperative Femoral Neuropathy  

PubMed Central

Surgical excision was performed on a 30-years old woman with a painful mass on her left thigh. The pathologic findings on the mass indicated fibromatosis. After the operation, she complained of allodynia and spontaneous pain at the operation site and ipsilateral lower leg. We treated her based on postoperative femoral neuropathy, but symptom was aggravated. We found a large liposarcoma in her left iliopsoas muscle which compressed the lumbar plexus. In conclusion, the cause of pain was lumbar plexopathy related to a mass in the left iliopsoas muscle. Prompt diagnosis of acute neuropathic pain after an operation is important and management must be based on exact causes.

Lee, Ki Hwa; Choe, Ji Hyun; Lee, Sang Eun; Park, Jae Hong; Bang, Si Ra; Kim, Yong Han

2011-01-01

67

Ultrasound-Guided Supraclavicular Brachial Plexus Block  

Microsoft Academic Search

In this study, we evaluated state-of-the-art ultrasound technology for supraclavicular brachial plexus blocks in 40 outpatients. Ultrasound imaging was used to identify the brachial plexus before the block, guide the block needle to reach target nerves, and visualize the pattern of local anesthetic spread. Needle position was further confirmed by nerve stimulation before injec- tion. The block technique we describe

Vincent W. S. Chan; Anahi Perlas; Regan Rawson; Olusegun Odukoya

2003-01-01

68

Radiation-Induced Grafting on Polyamides.  

National Technical Information Service (NTIS)

Earlier work indicated that in the radiation-induced grafting of vinyl monomers on polymeric films, the plasticity of the film being grafted is determined by the Hildebrand solubility parameter of the grafting solution. In the grafting of styrene on nylon...

J. E. Wilson

1973-01-01

69

Radiation-induced leukemias in ankylosing spondylitis  

SciTech Connect

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.

Toolis, F. (Royal Infirmary, Edinburgh, UK); Potter, B.; Allan, N.C.; Langlands, A.O.

1981-10-01

70

Monitor for Radiation-Induced Heating.  

National Technical Information Service (NTIS)

The patent relates to a susceptive material that is to be examined with respect to radiation-induced heating sealed within a capsule composed of a material such as stainless steel. The remaining capsule volume is filled with a liquid metal that has a grea...

W. R. Wallin V. W. Lowery R. R. Smith

1974-01-01

71

Terahertz radiation induced edge currents in graphene  

Microsoft Academic Search

We report on the observation of the terahertz radiation induced edge photogalvanic effect. The directed net electric current is generated in single layer graphene by the irradiation of the samples' edges with linearly or circularly polarized terahertz laser radiation at normal incidence. We show that the directed net electric current stems from the sample edges, which reduce locally the symmetry

C. Drexler; J. Karch; P. Olbrich; M. Fehrenbacher; M. M. Glazov; S. A. Tarasenko; D. Weiss; J. Eroms; R. Yakimova; S. Lara-Avila; S. Kubatkin; E. L. Ivchenko; M. Ostler; F. Fromm; T. Seyller; S. D. Ganichev

2011-01-01

72

[Quantification of radiation-induced genetic risk].  

PubMed

Associated with technical advances of our civilization is a radiation- and chemically-induced increase in the germ cell mutation rate in man. This would result in an increase in the frequency of genetic diseases and would be detrimental to future generations. It is the duty of our generation to keep this risk as low as possible. The estimation of the radiation-induced genetic risk of human populations is based on the extrapolation of results from animal experiments. Radiation-induced mutations are stochastic events. The probability of the event depends on the dose; the degree of the damage does not. The different methods to estimate the radiation-induced genetic risk will be discussed. The accuracy of the predicted results will be evaluated by a comparison with the observed incidence of dominant mutations in offspring born to radiation exposed survivors of the Hiroshima and Nagasaki atomic bombings. These methods will be used to predict the genetic damage from the fallout of the reactor accident at Chernobyl. For the exposure dose we used the upper limits of the mean effective life time equivalent dose from the fallout values in the Munich region. According to the direct method for the risk estimation we will expect for each 100 to 500 spontaneous dominant mutations one radiation-induced mutation in the first generation. With the indirect method we estimate a ratio of 100 dominant spontaneous mutations to one radiation-induced dominant mutation. The possibilities and the limitations of the different methods to estimate the genetic risk will be discussed. The discrepancy between the high safety standards for radiation protection and the low level of knowledge for the toxicological evaluation of chemical mutagens will be emphasized. PMID:3589954

Ehling, U H

1987-05-01

73

Lumbosacral plexopathy due to a rupture of a common Iliac artery aneurysm.  

PubMed

We report a case of lumbosacral plexopathy caused by the rupture of a common iliac artery aneurysm. The patient presented with sciatic type symptoms of lower back pain radiating to his left leg with associated numbness and weakness in the L4-S1 distribution. He also had reduced anorectal tone. A CT scan showed a large haematoma in the left side of the pelvis from a ruptured 8 cm common iliac artery aneurysm. Sciatica is commonly due to a prolapsed intervertebral disc, although spinal canal stenosis, spondylolisthesis, piriformis syndrome and spinal tumours and other causes need to be considered. This case serves to increase the awareness of the possibility of another uncommon cause, especially when additional atypical neurological symptoms exist. PMID:20796013

Bushby, Nathan; Wickramasinghe, Seneviratne Yapage Buddhimth Thavanga; Wickramasinghe, Daishini Nayomi Sagarika

2010-08-01

74

Postpartum lumbosacral plexopathy limited to autonomic and perineal manifestations: clinical and electrophysiological study of 19 patients.  

PubMed

The objective was to describe perineal electrophysiological findings and to determine their diagnostic value in a type of lumbosacral plexopathy after vaginal delivery, which only involves the lower part of the plexus (S2-S4). Consecutive female patients referred to an outpatients' urodynamic clinic were the source. Nineteen previously healthy women, 13 multiparae and six para 1, were investigated. Mean age was 33.7 (SD 5.4) (range 28-41) years. All of them presented with urinary (stress incontinence 14, dysuria five), anorectal (faecal incontinence eight, dyskesia one), or sexual dysfunctions (hypoorgasmia or anorgasmia six) after vaginal delivery. No associated lower limb sensory or motor deficits were noted. All the patients had electrophysiological recordings (bulbocavernosus muscle EMG, measurements of the bulbocavernosus reflex latencies (BCRLs), somatosensory evoked potentials of the pudendal nerve (SEPPNs), and pudendal nerve terminal motor latencies (PNTMLs)). Cystometry and urethral pressure profile (UPP) were performed in the 14 patients with stress urinary incontinence. Perineal electrophysiological examination disclosed signs of denervation in the perineal muscles in all the cases, prolonged BCRLs in 17/19, and abolished BCRLs in 2/19, abnormal SEPPN in 1/19, and normal PNTMLs in all the patients. Urodynamic investigations disclosed low urethral closure pressure for age (< 50 cm H(2)O) in half of the patients. In conclusion, Lower postpartum lumbosacral plexopathy is evoked when perineal sensory disturbances whether or not associated with urinary or faecal incontinence persist after a history of a difficult vaginal delivery. Electrophysiological investigations precisely identify the site of the lesion and demonstrate distal innervation integrity. PMID:10811704

Ismael, S S; Amarenco, G; Bayle, B; Kerdraon, J

2000-06-01

75

Rdiasensitivity and radiation-induced mutability: an empirical relationship.  

PubMed

The total genome size of various species can apparently define the radiation-induced mutability and radiosensitivity for these species. An empirical expression has been derived which relates the radiation-induced mutation rates of different species to their total DNA content and radiation-induced inactivation rates. PMID:1202558

Trujillo, R; Dugan, V L

1975-10-01

76

Radiation-induced leukemia: lessons from history.  

PubMed

Beginning in 1895, with the discovery of x-rays, alpha and beta radiation, uranium, radium, thorium, and polonium, the fascinating story of the beginning of knowledge concerning the existence of ionizing radiation unfolds. This brief history of radiation and leukemia is divided into two main parts: the first 50 years, which deals with the confusion regarding radiation effects and the failure to clearly recognize that exposure to ionizing radiation may induce leukemia. The second part focuses on the last 60 years, when the radiation induction of leukemia was accepted and some progress achieved in understanding the clinical and pathophysiological characteristics of radiation-induced leukemia. Particular attention in this is paid to the effects of radiation on the survivors of Hiroshima and Nagasaki. The discussion in this section also covers some concepts of radiation-induced cell damage and ruminations on unanswered questions. PMID:17336261

Finch, Stuart C

2007-03-01

77

PROTON TUNNELING IN RADIATION-INDUCED MUTATION.  

PubMed

The equilibrium proton distribution and tunneling rate in the N-H. . . N hydrogen bond of the guanine-cytosine base pair have been calculated quantum mechanically for the ground state, a charge-transfer excited state, and positive and negative ionic states. These results are consistent with the idea that tautomeric rearrangement can be a cause of radiation induced mutation or carcinogenesis. PMID:14191703

REIN, R; HARRIS, F E

1964-10-30

78

Radiation-induced dechlorination of hexachlorobenzene  

NASA Astrophysics Data System (ADS)

A study on radiation-induced dechlorination of hexachlorobenzene in alkaline ethanol solution was performed. At the beginning a higher efficiency for dechlorination has been found. The dechlorination is a chain reaction. The solubility of radiolytic products in ethanol-water (v/v 1:4) is higher than that of HCB in the same solvent. Hexachlorobenzene could be transfered into the solution and degraded partially if the soil contaminated by hexachlorobenzene was mixed with ethanol, then irradiated with ?-rays.

Yongke, He; Hongtao, Chen; Xiangrong, Sheng; Jilan, Wu

1993-10-01

79

Genistein mitigates radiation-induced testicular injury.  

PubMed

The present study investigated the radioprotective effect of a multifunctional soy isoflavone, genistein, with the testicular system. Genistein was administered (200?mg/kg body weight) to male C3H/HeN mice by subcutaneous injection 24?h prior to pelvic irradiation (5?Gy). Histopathological parameters were evaluated 12?h and 21?days post-irradiation. Genistein protected the germ cells from radiation-induced apoptosis (p?radiation-induced reduction in testis weight, seminiferous tubular diameter, seminiferous epithelial depth and sperm head count in the testes (p?radiation-induced ROS production. The results indicate that genistein protects from testicular dysfunction induced by gamma-irradiation by an antiapoptotic effect and recovery of spermatogenesis. PMID:22162311

Kim, Joong-Sun; Heo, Kyu; Yi, Joo-Mi; Gong, Eun Ji; Yang, Kwangmo; Moon, Changjong; Kim, Sung-Ho

2012-08-01

80

Imaging Radiation-Induced Normal Tissue Injury  

PubMed Central

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.

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

2013-01-01

81

Brachial plexus injury: treatment options and outcomes.  

PubMed

The brachial plexus is a series of nerves formed by roots of cervical segments 5 to 8 (C5-C8) as well as the first thoracic nerve (T1). It functions to provide sensation and motor innervation to the skin and muscles of the chest and upper limb. It does so through different segments: roots, trunks, divisions, and cords. Injuries to the brachial plexus occur relatively frequently and are due mainly to traumatic accidents that lead to traction or compression of the nerve roots. When considering the etiology and treatment of such injuries, it is important to make a distinction between adult versus obstetric brachial plexus injury. Although several surgical treatment options are described and used for patients with brachial plexus injury, no perfect remedy currently exists. Prevention and safety should be the focus. At the same time, high-quality studies and new technology and techniques are needed to determine more effective treatments for this group. PMID:25006897

Arzillo, Samantha; Gishen, Kriya; Askari, Morad

2014-07-01

82

Neurinomas of the brachial plexus: case report.  

PubMed

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

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

1999-01-01

83

Radiation Induces Acute Alterations in Neuronal Function  

PubMed Central

Every year, nearly 200,000 patients undergo radiation for brain tumors. For both patients and caregivers the most distressing adverse effect is impaired cognition. Efforts to protect against this debilitating effect have suffered from inadequate understanding of the cellular mechanisms of radiation damage. In the past it was accepted that radiation-induced normal tissue injury resulted from a progressive reduction in the survival of clonogenic cells. Moreover, because radiation-induced brain dysfunction is believed to evolve over months to years, most studies have focused on late changes in brain parenchyma. However, clinically, acute changes in cognition are also observed. Because neurons are fully differentiated post-mitotic cells, little information exists on the acute effects of radiation on synaptic function. The purpose of our study was to assess the potential acute effects of radiation on neuronal function utilizing ex vivo hippocampal brain slices. The cellular localization and functional status of excitatory and inhibitory neurotransmitter receptors was identified by immunoblotting. Electrophysiological recordings were obtained both for populations of neuronal cells and individual neurons. In the dentate gyrus region of isolated ex vivo slices, radiation led to early decreases in tyrosine phosphorylation and removal of excitatory N-methyl-D-aspartate receptors (NMDARs) from the cell surface while simultaneously increasing the surface expression of inhibitory gamma-aminobutyric acid receptors (GABAARs). These alterations in cellular localization corresponded with altered synaptic responses and inhibition of long-term potentiation. The non-competitive NMDAR antagonist memantine blocked these radiation-induced alterations in cellular distribution. These findings demonstrate acute effects of radiation on neuronal cells within isolated brain slices and open new avenues for study.

Wu, Peter H.; Coultrap, Steven; Pinnix, Chelsea; Davies, Kurtis D.; Tailor, Ramesh; Ang, Kian K.; Browning, Michael D.; Grosshans, David R.

2012-01-01

84

Radiation induced recombination processes in AIN ceramics  

NASA Astrophysics Data System (ADS)

Luminescence processes are studied for aluminum nitride, AlN, ceramics after exposure to ionizing radiation and ultraviolet radiation (UVR) using the methods of photoluminescence (PL), optically stimulated luminescence (OSL) and thermoluminescence (TL). The luminescence processes are explained in terms of radiation-induced charge transfer and radiative recombination of the donor-acceptor pairs, based on oxygen-related defects of the AlN crystalline lattice. The comparative effects of the two types of radiation, the efficiency of TL and OSL and the optimal sintering procedure of the ceramics are discussed for an AlN ceramic proposed for potential application in dosimetry.

Trinkler, L.; Berzina, B.

2001-10-01

85

Radiation-induced long thoracic nerve palsy  

SciTech Connect

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.

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

1987-09-15

86

Radiation induced conductivity in space dielectric materials  

NASA Astrophysics Data System (ADS)

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® 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® 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.

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

2014-01-01

87

Radiation-Induced Effects on Microstructure  

SciTech Connect

Irradiation of materials with particles that are sufficiently energetic to create atomic displacements can induce significant microstructural alteration, ranging from crystalline-to-amorphous phase transitions to the generation of large concentrations of point defect or solute aggregates in crystalline lattices. These microstructural changes typically cause significant changes in the physical and mechanical properties of the irradiated material. A variety of advanced microstructural characterization tools are available to examine the microstructural changes induced by particle irradiation, including electron microscopy, atom probe field ion microscopy, X-ray scattering and spectrometry, Rutherford backscattering spectrometry, nuclear reaction analysis, and neutron scattering and spectrometry. Numerous reviews, which summarize the microstructural changes in materials associated with electron and heavy ion or neutron irradiation, have been published. These reviews have focused on pure metals as well as model alloys, steels, and ceramic materials. In this chapter, the commonly observed defect cluster morphologies produced by particle irradiation are summarized and an overview is presented on some of the key physical parameters that have a major influence on microstructural evolution of irradiated materials. The relationship between microstructural changes and evolution of physical and mechanical properties is then summarized, with particular emphasis on eight key radiation-induced property degradation phenomena. Typical examples of irradiated microstructures of metals and ceramic materials are presented. Radiation-induced changes in the microstructure of organic materials such as polymers are not discussed in this overview.

Zinkle, Steven J [ORNL

2012-01-01

88

Role of neurotensin in radiation-induced hypothermia in rats  

SciTech Connect

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

Kandasamy, S.B.; Hunt, W.A.; Harris, A.H. (Armed Forces Radiobiology Research Institute, Bethesda, MD (USA))

1991-05-01

89

Radiation-induced intracranial meningioma and multiple cavernomas.  

PubMed

Brain irradiation has several well-known long-term side effects, including radiation-induced neoplasms and vasculopathy. In this case report, we describe an extremely rare case of meningioma and 15 cavernomas developing in a 29-year-old man, 19 years after cranial irradiation for posterior cranial fossa medulloblastoma. To our knowledge, this is the first case of a radiation-induced meningioma accompanied by this many radiation-induced cavernous angiomas. PMID:24051144

Chourmouzi, Danai; Papadopoulou, Elissavet; Kontopoulos, Athanasios; Drevelegas, Antonios

2013-01-01

90

Management of radiation-induced rectal bleeding.  

PubMed

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

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

2013-11-01

91

Radiation-induced electron migration along DNA  

SciTech Connect

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.

Fuciarelli, A.F.; Sisk, E.C.; Miller, J.H. [Pacific Northwest Lab., Richland, WA (United States); Zimbrick, J.D. [National Research Council, Washington, DC (United States)

1994-04-01

92

Radiation-induced chronic arterial injury  

SciTech Connect

Acute arterial disruption associated with infection, previous irradiation, and the postoperative state is a well-described entity. The recognition of a chronic form of radiation-induced arterial injury presenting years after therapeutic doses of radiation is less well appreciated. This paper summarizes the vital data obtained by reviewing the literature concerning 162 cases of arterial injury associated with prior radiotherapy. The vessels involved include coronary arteries, the aorta, renal arteries, the extra- and intracranial circulation, the ilio-femoral system, and the upper extremity arteries. A review of the histologic findings, the studies regarding pathogenesis, and the morphology of the lesions found in these 162 patients suggests a disease distinct from the atherosclerotic process. 181 references.

Himmel, P.D.; Hassett, J.M.

1986-01-01

93

Systematic Evaluation Of Brachial Plexus Injuries  

PubMed Central

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

Haynes, Scott

1993-01-01

94

Brachial plexus variations during the fetal period.  

PubMed

The brachial plexus is an important nervous system structure. It can be injured during the perinatal period and by postnatal damage. The goal of this study was to assess human fetal brachial plexus variability. A total of 220 brachial plexuses were surgically prepared from 110 human fetuses aged 14-32 weeks of fetal life (50 females and 60 males) ranging in CRL from 80 to 233 mm. The study incorporated the following methods: dissectional and anthropological, digital image acquisition, digital image processing using Image J and GIMP software, and statistical methods (Statistica 9.0). Symmetry and sexual dimorphism were examined. Anomalies of the brachial plexuses were observed in 117 (53.18 %) cases. No sexual dimorphism was found. It was observed that cord variations occurred more often on the left side. Division variants (33.64 %) occurred most often, but also cords (18.18 %) as well as root nerves and terminal ramifications (15.90 %) were found. Trunk anomalies were rare and occurred in only 5.45 % of plexuses. Three height types of median nerve roots in combination with the nerve were distinguished. In one-third of cases, median nerve root connections were found below the axillary fossa and even half in the proximal part of the humerus. In conclusion, the brachial plexus was characterized for anatomical structural variability. Most often division and cord variations were observed. Anomalies occurred regardless of sex or body side except for cord variants. Brachial plexus variation recognition is significant from the neurosurgical and traumatological point of view. PMID:22945314

Wo?niak, Jowita; K?dzia, Alicja; Dudek, Krzysztof

2012-12-01

95

Tenosynovial giant cell tumour of brachial plexus.  

PubMed

Tenosynovial giant cell tumours (TGT) are benign tumours that arise in the synovial lining of joints, tendon sheaths and bursae. Tumours arising from the vertebral column are extremely rare, with few cases reported. In this article, we describe an unusual case of an extra-articular TGT of the brachial plexus, arising from the synovium of the vertebral facet joint. To our knowledge and after a review of the literature, this is the first patient with a TGT involving the brachial plexus. The clinical, radiological and histological features of this tumour are described together with a brief discussion of management options. PMID:24380756

Ye, Joshua Mingsheng; Ye, Mingwei J; Rogers, Te Whiti; Gonzales, Michael; Lo, Patrick

2014-06-01

96

Radiation-induced osteosarcoma of the sphenoid bone  

SciTech Connect

The case of a patient who developed osteosarcoma in the sphenoid bone 15 years after radiation therapy for a craniopharyngioma is reported. Radiation-induced osteosarcoma of the sphenoid bone has not been reported previously. Reported cases of radiation-induced osteosarcomas are reviewed.

Tanaka, S.; Nishio, S.; Morioka, T.; Fukui, M.; Kitamura, K.; Hikita, K. (Kyushui Univ., Fukuoka (Japan))

1989-10-01

97

Synchronous radiation-induced orbital meningioma and multiple cavernomas.  

PubMed

Synchronous radiation-induced tumours are extremely rare. We present the first reported case of synchronous radiation-induced orbital meningioma and cavernomas of the cerebellum and bilateral basal ganglia, presenting 16 years after ionizing radiation therapy for parietal anaplastic ependymoma, at the age of five. This case again underscores the risks of radiotherapy to children. PMID:20491803

Paramanathan, Nirosha; Ooi, Kenneth Gek-Jin; Reeves, Dianne; Wilcsek, Geoff A

2010-05-01

98

Cathodoluminescence of radiation-induced zircon  

NASA Astrophysics Data System (ADS)

Zircon occurs as a common accessory mineral in igneous, metamorphic and sedimentary rocks, and maintains much information on thermal history, metamorphic process and natural radiation dose accumulated in the mineral. U-Pb zircon dating (e.g., SHRIMP) is an important tool to interpret a history of the minerals at a micrometer-scale, where cathodoluminescence (CL) image has been used for identification of internal zones and domains having different chemical compositions and/or structures with a high spatial resolution. The CL of zircon is derived from various types of emission centers, which are derived from impurities such as rare earth elements (REE) and structural defects. In fact, the CL features of zircon are closely related to metamorphic process and radiation from contained radionuclides as well as geochemical condition of its formation. Most zircon has yellow emission, which seems to be assigned to UO2 centers or radiation-induced defect during metamictization of the lattice by alpha particles from the decay of U and Th. In this study, the radiation effects on zircon CL have been studied for He+ ion-implanted samples annealed at various temperatures to clarify radiation-induced defect centers involved with the yellow CL emission in zircon. Single crystals of zircon from Malawi (MZ), Takidani granodiorite (TZ) and Kurobegawa granite (KZ) were selected for He+ ion implantation experiments. The polished plates of the samples were implanted by He+ ion 4.0 MeV corresponding to energy of alpha particle from 238 U and 232Th. CL spectra in the range from 300 to 800 nm with 1 nm step were measured by a scanning electron microscopy-cathodoluminescence (SEM-CL). CL spectra of untreated and annealed zircon show emission bands at ~370 nm assigned to intrinsic defect centers and at ~480, ~580 and ~760 nm to trivalent Dy impurity centers (Cesbron et al., 1995; Gaft et al, 2005). CL emissions in the yellow-region were observed in untreated zircon. The TZ and KZ indicate youngest formation ages of 1.93-1.20 Ma and 1.7-0.9 Ma, respectively (Harayama,1994; Harayama et al., 2010) in the world. In this case, it is hardly to detect yellow CL emissions derived from radiation-induced defect center, suggesting low radiation dose of alpha radiation from 238U and 232Th on them. CL spectra of MZ, TZ and KZ showed an increase in the intensities of yellow emissions with an increase in radiation dose of He+ ion implantation, though He+ ion implantation reduces the intensities of their impurity centers. CL intensity in the yellow region depends on radiation dose of He+ ion implantation. Therefore, if the component of yellow emission could be deconvoluted from the CL spectra in zircon, its intensity will be used for an indicator to evaluate total exposure doses on it during geological age.

Tsuchiya, Y.; Nishido, H.; Kayama, M.; Noumi, Y.

2013-12-01

99

Brachial diplegia in central pontine myelinolysis  

Microsoft Academic Search

A patient developed weakness in the upper limbs, eventually causing brachial diplegia with only slight paresis of the legs after rapid correction of severe hyponatraemia. Pseudobulbar palsy, mental confusion and urinary incontinence were also present. CT scan showed a zone of lucency in the pons. Clinical recovery occurred and the zone of lucency had disappeared 12 months after the appearance

R. Alberca; L. M. Iriarte; P. Rasero; F. Villalobos

1985-01-01

100

Ankle-brachial index in HIV infection  

Microsoft Academic Search

Prognosis for patients with the human immunodeficiency virus (HIV) has improved with the introduction of highly active antiretroviral therapy (HAART). Evidence over recent years suggests that the incidence of cardiovascular disease is increasing in HIV patients. The ankle-brachial index (ABI) is a cheap and easy test that has been validated in the general population. Abnormal ABI values are associated with

Julián Olalla; Daniel Salas; Javier de la Torre; Alfonso del Arco; José Luis Prada; Francisco Martos; Emilio Perea-Milla; Javier García-Alegría

2009-01-01

101

What has changed in brachial plexus surgery?  

PubMed Central

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

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

2013-01-01

102

Response to chemotherapy of a radiation-induced glioblastoma multiforme  

Microsoft Academic Search

Summary\\u000a Background  Radiation-induced glioblastoma multiforme (GBM) is particularly resistant to treatment and therapeutic options are limited.\\u000a We report a patient with a radiation-induced GBM who had a complete response to carmustine and survived for 44 months.\\u000a \\u000a \\u000a \\u000a Patients and Methods  Case report of a 38-year-old man with a radiation-induced GBM that responded to carmustine.\\u000a \\u000a \\u000a \\u000a Results  Our patient developed a left occipital GBM 35 years after a

Linda Nicolardi; Lisa M. DeAngelis

2006-01-01

103

Delayed Radiation-Induced Vasculitic Leukoencephalopathy  

SciTech Connect

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.

Rauch, Philipp J. [Departments of Pathology and Neurosurgery, Yale University School of Medicine, New Haven, Connecticut (United States); Faculty of Medicine, University of Heidelberg, Heidelberg (Germany); Park, Henry S. [Departments of Pathology and Neurosurgery, Yale University School of Medicine, New Haven, Connecticut (United States); Knisely, Jonathan P.S. [Department of Radiation Medicine, North Shore University Hospital, Manhasset, New York (United States); Chiang, Veronica L. [Departments of Pathology and Neurosurgery, Yale University School of Medicine, New Haven, Connecticut (United States); Vortmeyer, Alexander O., E-mail: alexander.vortmeyer@yale.edu [Departments of Pathology and Neurosurgery, Yale University School of Medicine, New Haven, Connecticut (United States)

2012-05-01

104

Modification of Synthetic Fibers by Radiation-Induced Grafting.  

National Technical Information Service (NTIS)

The present report describes studies to modify properties of synthetic fibers by radiation-induced grafting technique. This technique was employed since it is considered to be generally applicable to the grafting of a radically polymerizable monomer onto ...

K. Kaji

1981-01-01

105

Treatment of radiation-induced cystitis with hyperbaric oxygen  

SciTech Connect

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.

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

1985-08-01

106

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

Microsoft Academic Search

Xerostomia, or oral dryness, is one of the most common complaints experienced by patients who have had radiotherapy of the\\u000a oral cavity and neck region. The hallmarks of radiation-induced damage are acinar atrophy and chronic inflammation of the\\u000a salivary glands. The early response, resulting in atrophy of the secretory cells without inflammation might be due to radiation-induced\\u000a apoptosis. In contrast,

H.-J. Guchelaar; A. Vermes; J. H. Meerwaldt

1997-01-01

107

Bilateral brachial plexus compressive neuropathy (crutch palsy).  

PubMed

Brachial plexus compressive neuropathy following the use of axillary crutches (crutch palsy) is a rare but well-recognized entity. Most reported cases involve the posterior cord of the brachial plexus in children and have resolved spontaneously within 8-12 weeks. We recently treated a 36-year-old man who was using axillary crutches for mobilization after a supracondylar femoral fracture. Bilateral posterior cord (predominantly radial nerve) compressive neuropathy subsequently developed, with lesser involvement of the ulnar and median nerves. The patient had little to no improvement clinically 8 weeks after the estimated onset of the palsy, and an electromyogram at that time confirmed the presence of a severe axonotmesis lesion of the radial, median, and ulnar nerves bilaterally. The patient was treated with static cock-up wrist splinting and discontinuation of the axillary crutches. Return of sensory and motor function was delayed but occurred within 9 months. PMID:9057152

Raikin, S; Froimson, M I

1997-01-01

108

Treatment Options for Brachial Plexus Injuries  

PubMed Central

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.

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

2014-01-01

109

Axillary brachial plexus blockade in moyamoya disease?  

PubMed Central

Moyamoya disease is characterized by steno-occlusive changes of the intracranial internal carotid arteries. Cerebral blood flow and metabolism are strictly impaired. The goal in perioperative anaesthetic management is to preserve the stability between oxygen supply and demand in the brain. Peripheral nerve blockade allows excellent neurological status monitoring and maintains haemodynamic stability which is very important in this patient group. Herein, we present an axillary brachial plexus blockade in a moyamoya patient operated for radius fracture.

Yalcin, Saban; Cece, Hasan; Nacar, Halil; Karahan, Mahmut Alp

2011-01-01

110

Axillary brachial plexus blockade in moyamoya disease?  

PubMed

Moyamoya disease is characterized by steno-occlusive changes of the intracranial internal carotid arteries. Cerebral blood flow and metabolism are strictly impaired. The goal in perioperative anaesthetic management is to preserve the stability between oxygen supply and demand in the brain. Peripheral nerve blockade allows excellent neurological status monitoring and maintains haemodynamic stability which is very important in this patient group. Herein, we present an axillary brachial plexus blockade in a moyamoya patient operated for radius fracture. PMID:21712873

Yalcin, Saban; Cece, Hasan; Nacar, Halil; Karahan, Mahmut Alp

2011-03-01

111

Pseudohypertension secondary to a noncompressible brachial artery  

PubMed Central

The interesting problem is considered of a comatose alcoholic diabetic with an extremely high systolic blood pressure, as determined by the usual means, who was subsequently found to have severe medial calcinosis and normal intraarterial blood pressure. The syndrome of the noncompressible brachial artery surely accounts for this patient's falsely elevated blood pressure reading. Though infrequently reported, this condition can be one cause of “difficult to control” hypertension in the elderly and in the diabetic patient. ImagesFIG. 1FIG. 2

Sheckman, Peter; Klassen, Gerald

1974-01-01

112

Brachial plexus block in a parturient.  

PubMed

We report a novel circumstance of brachial plexus anesthesia in a parturient. A 25-year-old woman at 34 weeks of gestation presented with a pathologic proximal right humerus fracture from an intramedullary mass. She was scheduled for tumor biopsy which was performed using a two-site ultrasound-guided brachial plexus block to maximize odds of complete anesthesia while minimizing the risk of phrenic nerve paresis. After a supraclavicular block with 0.5% ropivacaine 20 mL, we translated our ultrasound probe cephalad, inferior to the root of C7 where the divisions of the superior trunk could be seen in a tightly compact arrangement. An additional injection of 0.5% ropivacaine 20 mL was administered at this site, and the patient subsequently underwent successful biopsy without sedatives or analgesics, aside from local anesthetics. In the post-anesthesia care unit, she had normal respirations and oxygen saturations breathing room air, denied any shortness of breath or difficulty breathing, and was discharged shortly after her arrival. While we did not pursue radiologic examination to rule out hemidiaphragm paralysis, we assumed, as evidenced in a previous case report, that unlike most healthy patients, a parturient would demonstrate some clinical signs and/or symptoms of hemidiaphragm paralysis, given that the diaphragm is almost totally responsible for inspiration in the term parturient. This represents only the second brachial plexus block in a parturient reported in the literature; the first using ultrasound guidance and without respiratory embarrassment. PMID:24631059

Patzkowski, M; Scheiner, J

2014-05-01

113

Role of PPARs in Radiation-Induced Brain Injury  

PubMed Central

Whole-brain irradiation (WBI) represents the primary mode of treatment for brain metastases; about 200 000 patients receive WBI each year in the USA. Up to 50% of adult and 100% of pediatric brain cancer patients who survive >6 months post-WBI will suffer from a progressive, cognitive impairment. At present, there are no proven long-term treatments or preventive strategies for this significant radiation-induced late effect. Recent studies suggest that the pathogenesis of radiation-induced brain injury involves WBI-mediated increases in oxidative stress and/or inflammatory responses in the brain. Therefore, anti-inflammatory strategies can be employed to modulate radiation-induced brain injury. Peroxisomal proliferator-activated receptors (PPARs) are ligand-activated transcription factors that belong to the steroid/thyroid hormone nuclear receptor superfamily. Although traditionally known to play a role in metabolism, increasing evidence suggests a role for PPARs in regulating the response to inflammation and oxidative injury. PPAR agonists have been shown to cross the blood-brain barrier and confer neuroprotection in animal models of CNS disorders such as stroke, multiple sclerosis and Parkinson's disease. However, the role of PPARs in radiation-induced brain injury is unclear. In this manuscript, we review the current knowledge and the emerging insights about the role of PPARs in modulating radiation-induced brain injury.

Ramanan, Sriram; Zhao, Weiling; Riddle, David R.; Robbins, Mike E.

2010-01-01

114

Associated factors in 1611 cases of brachial plexus injury  

Microsoft Academic Search

Objective: To identify risk factors associated with brachial plexus injury in a large population.Methods: A computerized data set containing records from hospital discharge summaries of mothers and infants and birth certificates was examined. The deliveries took place in more than 300 civilian acute care hospitals in California between January 1, 1994, and December 31, 1995. Cases of brachial plexus injury

William M Gilbert; Thomas S Nesbitt; Beate Danielsen

1999-01-01

115

Radiation-induced damage studies of energetic materials.  

NASA Astrophysics Data System (ADS)

We present studies of synchrotron radiation-induced decomposition of PETN and TATB under conditions of high pressure, high temperature, and crystalline orientation. We have found that the decomposition rate varies dramatically under all three of these variables. The experiments were performed using white beam synchrotron radiation at the 16 BM-B and 16 BM-D sectors of the HP-CAT beamline at the Advanced Photon Source. Diffraction line intensities were measured as a function of time using energy-dispersive methods and angular-dispersive methods TATB showed dramatic slowing of the decomposition rate with pressure implying a positive activation volume of the activated complex whereas PETN showed little change in decomposition rate with pressure. Increased temperature increased the radiation-induced decomposition rate of TATB. Finally, we found dramatic differences in the radiation-induced decomposition rate for single crystals of explosives depending upon their orientation relative to the polarized x-ray beam.

Pravica, Michael; Giefers, Hubertus; Quine, Zachary; Romano, Edward; Bajar, Sean; Yulga, Brian; Yang, Wenge; Liermann, Hans Peter; Hooks, Daniel

2007-06-01

116

Adult brachial plexus injury: evaluation and management.  

PubMed

Adult traumatic brachial plexus injury involves injury of the C5-T1 spinal nerves. Common patterns of injury include "upper arm" and "total arm" types. The specific signs of preganglionic avulsion injury infer a poor prognosis for spontaneous recovery and surgery may be needed. Detailed preoperative evaluation is recommended for localization of the lesions. The treatment of upper arm type injury comprises restoration of elbow flexion and shoulder control. Good functional results may be achieved after multiple nerve transfers. The treatment of total arm type includes hand function reconstruction, in addition to shoulder and elbow treatment. Current options for hand function reconstruction include functioning free muscle transfers and nerve transfers. PMID:24095074

Limthongthang, Roongsak; Bachoura, Abdo; Songcharoen, Panupan; Osterman, A Lee

2013-10-01

117

Radiation-induced decomposition of explosives under extreme conditions  

Microsoft Academic Search

We present high-pressure and high temperature studies of the synchrotron radiation-induced decomposition of powder secondary high explosives pentaerythritol tetranitrate (PETN) and 1,3,5-triamino-2,4,6-trinitrobenzene (TATB) using white beam synchrotron radiation at the 16 BM-B and 16 BM-D sectors of the HP-CAT beamline at the Advanced Photon Source. The radiation-induced decomposition rate TATB showed dramatic slowing with pressure up to 26.6GPa (the highest

Hubertus Giefers; Michael Pravica; Wenge Yang; Peter Liermann

2008-01-01

118

Hemodynamic significance of high brachial pulse pressure in young men.  

PubMed

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

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

2004-04-01

119

Radiation-induced segregation in alloy X-750  

SciTech Connect

Microstructural and microchemical evolution of an Alloy X-750 heat under neutron irradiation was studied in order to understand the origin of irradiation-assisted stress corrosion cracking. Both clustering of point defects and radiation-induced segregation at interfaces were observed. Although no significant changes in the precipitate structure were observed, boundaries exhibited additional depletion of Cr and Fe and enrichment of Ni.

Kenik, E.A.

1996-12-31

120

Radiation-induced segregation in alloy X-750  

Microsoft Academic Search

Microstructural and microchemical evolution of an Alloy X-750 heat under neutron irradiation was studied in order to understand the origin of irradiation-assisted stress corrosion cracking. Both clustering of point defects and radiation-induced segregation at interfaces were observed. Although no significant changes in the precipitate structure were observed, boundaries exhibited additional depletion of Cr and Fe and enrichment of Ni.

Kenik

1996-01-01

121

Radiation induced CNS toxicity – molecular and cellular mechanisms  

Microsoft Academic Search

Radiotherapy of tumours proximal to normal CNS structures is limited by the sensitivity of the normal tissue. Prior to the development of prophylactic strategies or treatment protocols a detailed understanding of the mechanisms of radiation induced CNS toxicity is mandatory. Histological analysis of irradiated CNS specimens defines possible target structures prior to a delineation of cellular and molecular mechanisms. Several

C Belka; W Budach; R D Kortmann; M Bamberg

2001-01-01

122

Poor outcome in radiation-induced constrictive pericarditis  

SciTech Connect

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.

Karram, T.; Rinkevitch, D.; Markiewicz, W. (Technion Medical School, Haifa (Israel))

1993-01-15

123

The radiation-induced lesions which trigger the bystander effect  

Microsoft Academic Search

The ionizing radiation induced bystander effect is initiated by damage to a cellular molecule which then gives rise to a signal exported to other cells. The nature of this damage is considered with the understanding that it may not be the same as that responsible for the traditional cellular effects of radiation. Consideration is give to amounts of endogenous damage

John F Ward

2002-01-01

124

Radiation-induced nonlinear optical response of quartz fibers  

NASA Astrophysics Data System (ADS)

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

Plaksin, O. A.

2006-10-01

125

Radiation-Induced Phosphorus Segregation in Austenitic and Ferritic Alloys.  

National Technical Information Service (NTIS)

The radiation induced surface segregation (RIS) of phosphorus in stainless steel attained a maximum at a dose of 0.8 dpa then decreased continually with dose. This decrease in the surface segregation of phosphorus at high dose levels has been attributed t...

J. L. Brimhall D. R. Baer R. H. Jones

1983-01-01

126

Hyperbaric Oxygen Therapy for Radiation-induced Optic Neuropathy  

Microsoft Academic Search

Introduction: Radiation-induced optic neuropathy (RON) is an infrequent but devastating consequence of radiation exposure to the visual pathways, usually following months to years after the treatment of paranasal or intracranial tumours. Hyperbaric oxygen (HBO) therapy is one of several therapies that have been tried for this condition. The purpose of this review is to describe the clinical characteristics of RON,

Richard L Levy; Neil R Miller

127

Radiation-induced cognitive impairment-from bench to bedside  

PubMed Central

Approximately 100 000 patients per year in the United States with primary and metastatic brain tumor survive long enough (>6 months) to develop radiation-induced brain injury. Before 1970, the human brain was thought to be radioresistant; the acute central nervous system (CNS) syndrome occurs after single doses of ?30 Gy, and white matter necrosis can occur at fractionated doses of ?60 Gy. Although white matter necrosis is uncommon with modern radiation therapy techniques, functional deficits, including progressive impairments in memory, attention, and executive function have become increasingly important, having profound effects on quality of life. Preclinical studies have provided valuable insights into the pathogenic mechanisms involved in radiation-induced cognitive impairment. Although reductions in hippocampal neurogenesis and hippocampal-dependent cognitive function have been observed in rodent models, it is important to recognize that other brain regions are affected; non–hippocampal-dependent reductions in cognitive function occur. Neuroinflammation is viewed as playing a major role in radiation-induced cognitive impairment. During the past 5 years, several preclinical studies have demonstrated that interventional therapies aimed at modulating neuroinflammation can prevent/ameliorate radiation-induced cognitive impairment independent of changes in neurogenesis. Translating these exciting preclinical findings to the clinic offers the promise of improving the quality of life in patients with brain tumors who receive radiation therapy.

Greene-Schloesser, Dana; Robbins, Mike E.

2012-01-01

128

Radiation induces senescence and a bystander effect through metabolic alterations.  

PubMed

Cellular senescence is a state of irreversible growth arrest; however, the metabolic processes of senescent cells remain active. Our previous studies have shown that radiation induces senescence of human breast cancer cells that display low expression of securin, a protein involved in control of the metaphase-anaphase transition and anaphase onset. In this study, the protein expression profile of senescent cells was resolved by two-dimensional gel electrophoresis to investigate associated metabolic alterations. We found that radiation induced the expression and activation of glyceraldehyde-3-phosphate dehydrogenase that has an important role in glycolysis. The activity of lactate dehydrogenase A, which is involved in the conversion of pyruvate to lactate, the release of lactate and the acidification of the extracellular environment, was also induced. Inhibition of glycolysis by dichloroacetate attenuated radiation-induced senescence. In addition, radiation also induced activation of the 5'-adenosine monophosphate-activated protein kinase (AMPK) and nuclear factor kappa B (NF-?B) pathways to promote senescence. We also found that radiation increased the expression of monocarboxylate transporter 1 (MCT1) that facilitates the export of lactate into the extracellular environment. Inhibition of glycolysis or the AMPK/NF-?B signalling pathways reduced MCT1 expression and rescued the acidification of the extracellular environment. Interestingly, these metabolic-altering signalling pathways were also involved in radiation-induced invasion of the surrounding, non-irradiated breast cancer and normal endothelial cells. Taken together, radiation can induce the senescence of human breast cancer cells through metabolic alterations. PMID:24853433

Liao, E-C; Hsu, Y-T; Chuah, Q-Y; Lee, Y-J; Hu, J-Y; Huang, T-C; Yang, P-M; Chiu, S-J

2014-01-01

129

Use of probiotics for prevention of radiation-induced diarrhea  

PubMed Central

AIM: To investigate the efficacy of a high-potency probiotic preparation on prevention of radiation-induced diarrhea in cancer patients. METHODS: This was a double-blind, placebo-controlled trial. Four hundred and ninety patients who underwent adjuvant postoperative radiation therapy after surgery for sigmoid, rectal, or cervical cancer were assigned to either the high-potency probiotic preparation VSL#3 (one sachet t.i.d.,) or placebo starting from the first day of radiation therapy. Efficacy endpoints were incidence and severity of radiation-induced diarrhea, daily number of bowel movements, and the time from the start of the study to the use of loperamide as rescue medication. RESULTS: More placebo patients had radiation-induced diarrhea than VSL#3 patients (124 of 239 patients, 51.8%, and 77 of 243 patients, 31.6%; P < 0.001) and more patients given placebo suffered grade 3 or 4 diarrhea compared with VSL#3 recipients (55.4% and 1.4%, P < 0.001). Daily bowel movements were 14.7 ± 6 and 5.1 ± 3 among placebo and VSL#3 recipients (P < 0.05), and the mean time to the use of loperamide was 86 ± 6 h for placebo patients and 122 ± 8 h for VSL#3 patients (P < 0.001). CONCLUSION: Probiotic lactic acid-producing bacteria are an easy, safe, and feasible approach to protect cancer patients against the risk of radiation-induced diarrhea.

Delia, P; Sansotta, G; Donato, V; Frosina, P; Messina, G; De Renzis, C; Famularo, G

2007-01-01

130

Radiation induced sarcoma following treatment of breast cancer.  

PubMed

The occurrence of radiation induced sarcoma following treatment of breast cancer is rare. It has an average latency of ten years and it correlates with the dose and technique of radiation. The prognosis is poor due to delay in diagnosis. We present a case where a female patient developed a chondrosarcoma of sternoclavicular joint 19 years after radiotherapy for breast cancer. PMID:10921225

Pandey, K K; Kumar, R; Goel, A; Saharia, A

1999-01-01

131

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...

132

Radiation induces senescence and a bystander effect through metabolic alterations  

PubMed Central

Cellular senescence is a state of irreversible growth arrest; however, the metabolic processes of senescent cells remain active. Our previous studies have shown that radiation induces senescence of human breast cancer cells that display low expression of securin, a protein involved in control of the metaphase–anaphase transition and anaphase onset. In this study, the protein expression profile of senescent cells was resolved by two-dimensional gel electrophoresis to investigate associated metabolic alterations. We found that radiation induced the expression and activation of glyceraldehyde-3-phosphate dehydrogenase that has an important role in glycolysis. The activity of lactate dehydrogenase A, which is involved in the conversion of pyruvate to lactate, the release of lactate and the acidification of the extracellular environment, was also induced. Inhibition of glycolysis by dichloroacetate attenuated radiation-induced senescence. In addition, radiation also induced activation of the 5?-adenosine monophosphate-activated protein kinase (AMPK) and nuclear factor kappa B (NF-?B) pathways to promote senescence. We also found that radiation increased the expression of monocarboxylate transporter 1 (MCT1) that facilitates the export of lactate into the extracellular environment. Inhibition of glycolysis or the AMPK/NF-?B signalling pathways reduced MCT1 expression and rescued the acidification of the extracellular environment. Interestingly, these metabolic-altering signalling pathways were also involved in radiation-induced invasion of the surrounding, non-irradiated breast cancer and normal endothelial cells. Taken together, radiation can induce the senescence of human breast cancer cells through metabolic alterations.

Liao, E-C; Hsu, Y-T; Chuah, Q-Y; Lee, Y-J; Hu, J-Y; Huang, T-C; Yang, P-M; Chiu, S-J

2014-01-01

133

Cosmology for grand unified theories with radiatively induced symmetry breaking  

Microsoft Academic Search

The treatment of first-order phase transitions for standard grand unified theories is shown to break down for models with radiatively induced spontaneous symmetry breaking. It is argued that proper analysis of these transitions which would take place in the early history of the universe can lead to an explanation of the cosmological homogeneity, flatness, and monopole puzzles.

Andreas Albrecht; P. J. Steinhardt

1982-01-01

134

Fibromuscular dysplasia of the brachial artery associated with unilateral clubbing  

PubMed Central

A 46-year old male patient was admitted with a history of an extremely painful right upper arm, associated with unilateral clubbing. Duplex scanning and magnetic resonance imaging were suggestive of a pseudo-aneurysm of the brachial artery. Digital angiography showed an irregular brachial artery, associated with a small pseudo-aneurysm. The brachial artery was partially resected and reconstructed with a venous interposition graft. Pathological examination provided the final diagnosis of fibromuscular dysplasia. Although more encountered in women, this case report describes the occurrence of fibromuscular dysplasia in an unusual location in a male patient with a long-term follow-up.

De Waele, Michele; Lauwers, Patrick; Hendriks, Jeroen; Van Schil, Paul

2012-01-01

135

Brachial Plexus Injuries in Adults: Evaluation and Diagnostic Approach  

PubMed Central

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.

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

136

Simulation of Nucleation Kinetics of Radiation-Induced Defect Clusters in Irradiated Materials.  

National Technical Information Service (NTIS)

A numerical method for simulation kinetics of radiation-induced defect clusters in irradiated materials is developed. Calculations of nucleation kinetics of radiation-induced defect clusters under pulsed irradiation corresponding to continuous irradiation...

A. I. Ryazanov A. D. Sidorenko S. S. Filippov

1985-01-01

137

Infraclavicular brachial plexus block in Wilson's disease.  

PubMed

Wilson's disease (WD) is characterized by progressive copper accumulation with hepatic and neurological impairment. Anesthesia and surgical practices may exacerbate WD and liver damage, and even cause life-threatening liver failure. Due to this existing liver damage, anesthetic management is important in WD cases in terms of drug choice, dose, and technique used. This study reports an emergency surgical procedure for trauma in a 24-year-old WD patient suffering the disease for 18 years. The operation was planned under infraclavicular brachial plexus block because of a right supracondiller/proximal humerus fracture. The selected type of anesthetic technique and agents in WD is specific. The pharmacokinetic changes in these cases are difficult to predict and require attention to drug choice and dose. PMID:23833859

Tokgöz, Orhan; Yildirim, Mehmet Be?ir; Tüfek, Adnan; Celik, Feyzi; Gümü?, Abdurrahman; Kavak, Gönül Olmez

2013-02-01

138

Upper trunk brachial plexus injuries in contact sports.  

PubMed

Cervical nerve pinch syndrome, a neurapraxia of the brachial plexus, is a common occurrence in contact football. The incidence at two universities was approximately 49%. The more serious injury, brachial plexus axonotmesis, has received little attention in the literature. We are reporting 13 cases of brachial plexus axonotmesis. Ten were documented by electromyography. All involved the upper trunk. All but one patient recovered within a 3- to 42-week interval. These brachial plexus axonotmesis injuries may initially present as a cervical nerve pinch syndrome. All significant or repeated cervical nerve pinch injuries should be reexamined at 2 weeks. Those patient with axonotmesis should not be allowed to return to competition until they have achieved normal strength in the involved muscles and the electromyogram shows no signs of active denervation. PMID:907035

Clancy, W G; Brand, R L; Bergfield, J A

1977-01-01

139

Schwannoma of the brachial plexus presenting as a cystic swelling.  

PubMed

Schwannomas are benign nerve sheath tumours. A small percentage of these tumours arise from the brachial plexus. Cystic degeneration and hemorrhagic necrosis can occur in these tumours in up to 40% of the cases. Detailed preoperative evaluation and careful dissection during surgery will avoid post operative neurological complications. We report a case of schwannoma of the brachial plexus presenting as a cystic neck swelling which was successfully managed by us. PMID:23120083

Somayaji, K S G; Rajeshwari, A; Gangadhara, K S

2004-07-01

140

Radiation-induced transient darkening of optically transparent polymers  

SciTech Connect

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

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

1986-11-15

141

Radiation-induced decomposition of explosives under extreme conditions  

SciTech Connect

We present high-pressure and high temperature studies of the synchrotron radiation-induced decomposition of powder secondary high explosives pentaerythritol tetranitrate (PETN) and 1,3,5-triamino-2,4,6-trinitrobenzene (TATB) using white beam synchrotron radiation at the 16 BM-B and 16 BM-D sectors of the HP-CAT beamline at the Advanced Photon Source. The radiation-induced decomposition rate TATB showed dramatic slowing with pressure up to 26.6 GPa (the highest pressure studied), implying a positive activation volume of the activated complex. The decomposition rate of PETN varied little with pressure up to 15.7 GPa (the highest pressure studied). Diffraction line intensities were measured as a function of time using energy-dispersive methods. By measuring the decomposition rate as a function of pressure and temperature, kinetic and other constants associated with the decomposition reactions were extracted.

Giefers, Hubertus; Pravica, Michael; Yang, Wenge; Liermann, Peter (UNLV); (CIW)

2008-11-03

142

Radiation-induced lung injury: a hypersensitivity pneumonitis  

SciTech Connect

Radiation pneumonitis occurs 6 to 12 weeks after thoracic irradiation, and is thought to be due to direct radiation-induced lung injury. Four patients who developed pneumonitis after unilateral thoracic irradiation for carcinoma of the breast were studied with bronchoalveolar lavage, gallium scan of the lung, and respiratory function tests. On the irradiated side of the chest, all four patients showed an increase in total cells recovered from the lavage fluid and a marked increase in the percentage of lymphocytes. When results for the unirradiated lung were compared with results for the irradiated lung, there was a comparable increase in total cells and percentage of lymphocytes. Gallium scans showed increases for both irradiated and unirradiated lungs. Prompt improvement was seen after corticosteroid therapy in all patients. The fact that abnormal findings occur equally in irradiated and unirradiated lung is inconsistent with simple direct radiation-induced injury and suggests an immunologically mediated mechanism such as a hypersensitivity pneumonitis.

Gibson, P.G.; Bryant, D.H.; Morgan, G.W.; Yeates, M.; Fernandez, V.; Penny, R.; Breit, S.N.

1988-08-15

143

Preliminary studies on radiation-induced changes in chitosan  

NASA Astrophysics Data System (ADS)

Radiation-induced changes in chitosan irradiated in solid state and in aqueous solution were examined. Radiation yields of scission in solid state, determined by HPLC/GPC, are Gs = 0.9 in vacuum, Gs = 1.1 in air and Gs = 1.3 in oxygen; corresponding yields of crosslinking are equal to zero. Increase in absorbance at 247 and 290 nm was observed. Existence of post-effect, i.e. further decrease in molecular weight and increase in absorbance was detected. Radiation-induced changes in solution were studied by pulse radiolysis. Two time-separated first order processes of chain scission were found ( k1 = 1.4 x 10 4 s -1, k2 = 0.58 s -1). Time evolution of absorption spectrum of chitosan macroadicals (? max = 275 nm) was traced.

Ula?ski, P.; Rosiak, J.

144

Radiation-induced apoptosis in microvascular endothelial cells.  

PubMed Central

The response of the microvasculature to ionizing radiation is thought to be an important factor in the overall response of both normal tissues and tumours. It has recently been reported that basic fibroblast growth factor (bFGF), a potent mitogen for endothelial cells, protects large vessel endothelial cells from radiation-induced apoptosis in vitro. Microvessel cells are phenotypically distinct from large vessel cells. We studied the apoptotic response of confluent monolayers of capillary endothelial cells (ECs) to ionizing radiation and bFGF. Apoptosis was assessed by identifying changes in nuclear morphology, recording cell detachment rates and by detecting internucleosomal DNA fragmentation. Withdrawal of bFGF alone induces apoptosis in these monolayers. The magnitude of this apoptotic response depends upon the duration of bFGF withdrawal. Irradiation (2-10 Gy) induces apoptosis in a dose-dependent manner. Radiation-induced apoptosis occurs in a discrete wave 6-10 h after irradiation, and radiation-induced apoptosis is enhanced in cultures that are simultaneously deprived of bFGF. For example, 6 h after 10 Gy, 44.3% (s.e. 6.3%) of cells in the monolayer simultaneously deprived of bFGF exhibit apoptotic morphology compared with 19.8% (s.e. 3.8%) in the presence of bFGF. These studies show that either bFGF withdrawal or ionizing radiation can induce apoptosis in confluent monolayers of capillary endothelial cells and that radiation-induced apoptosis can be modified by the presence of bFGF. Images Figure 1 Figure 2 Figure 4 Figure 5

Langley, R. E.; Bump, E. A.; Quartuccio, S. G.; Medeiros, D.; Braunhut, S. J.

1997-01-01

145

Tristetraprolin Mediates Radiation-Induced TNF-? Production in Lung Macrophages  

PubMed Central

The efficacy of radiation therapy for lung cancer is limited by radiation-induced lung toxicity (RILT). Although tumor necrosis factor-alpha (TNF-?) signaling plays a critical role in RILT, the molecular regulators of radiation-induced TNF-? production remain unknown. We investigated the role of a major TNF-? regulator, Tristetraprolin (TTP), in radiation-induced TNF-? production by macrophages. For in vitro studies we irradiated (4 Gy) either a mouse lung macrophage cell line, MH-S or macrophages isolated from TTP knockout mice, and studied the effects of radiation on TTP and TNF-? levels. To study the in vivo relevance, mouse lungs were irradiated with a single dose (15 Gy) and assessed at varying times for TTP alterations. Irradiation of MH-S cells caused TTP to undergo an inhibitory phosphorylation at Ser-178 and proteasome-mediated degradation, which resulted in increased TNF-? mRNA stabilization and secretion. Similarly, MH-S cells treated with TTP siRNA or macrophages isolated from ttp (?/?) mice had higher basal levels of TNF-?, which was increased minimally after irradiation. Conversely, cells overexpressing TTP mutants defective in undergoing phosphorylation released significantly lower levels of TNF-?. Inhibition of p38, a known kinase for TTP, by either siRNA or a small molecule inhibitor abrogated radiation-induced TNF-? release by MH-S cells. Lung irradiation induced TTPSer178 phosphorylation and protein degradation and a simultaneous increase in TNF-? production in C57BL/6 mice starting 24 h post-radiation. In conclusion, irradiation of lung macrophages causes TTP inactivation via p38-mediated phosphorylation and proteasome-mediated degradation, leading to TNF-? production. These findings suggest that agents capable of blocking TTP phosphorylation or stabilizing TTP after irradiation could decrease RILT.

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

2013-01-01

146

Modulation of Radiation-Induced Apoptosis by Thiolamines  

NASA Technical Reports Server (NTRS)

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.

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

1997-01-01

147

Radiation-induced coordination topological defects in chalcogenide glasses  

NASA Astrophysics Data System (ADS)

The radiation-induced (gamma-quanta of Co-60 source) coordination topological defect formation in chalcogenide glasses of quasi-binary AS(2)S(3)-GeS2 system is studied using experimental techniques of IR Fourier spectroscopy and positron annihilation lifetime measurements. The new model of open-volume microvoids connected with negatively charged under-coordinated defects is developed at the basis of the obtained results.

Shpotyuk, O. I.; Filipecki, J.; Kozdras, A.; Balitska, V.

2003-01-01

148

Radiation-induced grain boundary segregation in nuclear reactor steels  

Microsoft Academic Search

The paper will review the various mechanisms of grain boundary segregation. These are: thermal equilibrium segregation (TES); neutron irradiation enhanced equilibrium segregation; thermal non-equilibrium segregation; and radiation-induced segregation (RIS). The neutron irradiation-induced mechanisms will be discussed in detail. Modelling of the neutron irradiation segregation effects will be outlined with reference to two approaches: non-equilibrium theory based models and rate theory

R. G. Faulkner

1997-01-01

149

Monitoring of radiation-induced germline mutation in humans.  

PubMed

Estimating the genetic hazards of radiation and other mutagens in humans depends on extrapolation from experimental systems. Recent data have shown that minisatellite loci provide a useful and sensitive experimental approach for monitoring radiation-induced mutation in humans. This review describes the progress made in validating this approach and presents the results of recent publications on the analysis of minisatellite mutation rates in the irradiated families. PMID:14652802

Dubrova, Yuri E

2003-09-01

150

Effect of Sobatum on radiation-induced toxicity in mice  

Microsoft Academic Search

Sobatum, the active fraction of the plant Solanum trilobatum was obtained from the petroleum ether\\/ethyl acetate (75:25) extractable portion. Sobatum was proven to be an anticancer agent by in vitro and in vivo methods. The aim of this study is to evaluate the effect of Sobatum on radiation-induced toxicity in mice. In this assay there are three groups. Group I,

P. V Mohanan; K. S Devi

1998-01-01

151

Radiation-induced outgassing from Type 304 stainless steel  

Microsoft Academic Search

A Type 304 stainless-steel vacuum system has been designed and constructed to study radiation-induced outgassing when this material is exposed to ⁶°Co gamma radiation. An analytical model has been developed that predicts the outgassing from Type 304 stainless steel to be 5 x 10⁻¹° Pa.l\\/cm².s per Mrad\\/h. Experiments determined the value for Type 304 stainless steel after bakeout at 300°C

T. P. Toepker; J. N. Anno

1979-01-01

152

Radiation induced leakage current in floating gate memory cells  

Microsoft Academic Search

Single ions impacting on SiO2 layers generate tracks of defects which may result in a Radiation Induced Leakage Current (RILC). This current is usually studied as the cumulative effect of ion-induced defects in capacitors with ultra-thin oxides. We are demonstrating and modeling this phenomenon in 10 nm oxides by using Floating Gate memories. The impact of a single, high-LET ion

G. Cellere; L. Larcher; A. Paccagnella; A. Visconti; M. Bonanomi

2005-01-01

153

Radiation-Induced Polymerization of a Series of Vinyl Ethers  

Microsoft Academic Search

The radiation-induced polymerization of methyl, ethyl, isobutyl, isopropyl, and tert-butyl vinyl ethers was studied under super-dry conditions. Methyl vinyl ether did not polymerize at measurable rates; ethyl vinyl ether polymerized readily but with a dose rate dependence of the rate of only 0.3. The other ethers polymerized with a square-root dependence of the rate on the dose rate. Good agreement

A. M. Goineau; J. Kohler; V. Stannett

1977-01-01

154

Radiation-induced bystander effects, carcinogenesis and models  

Microsoft Academic Search

Implications for carcinogenesis of radiation-induced bystander effects are both mechanistic and practical. They include induction of second cancers, perturbations to tissue social control and induction of genomic instability and delayed or immediate mutations in areas not receiving a direct deposition of energy. Bystander effects have consequences for DNA damage-mutation-cancer initiation paradigms of radiation carcinogenesis that provide the mechanistic justification for

Carmel Mothersill; Colin Seymour

2003-01-01

155

Radiation-Induced Bystander Effects in Cultured Human Stem Cells  

Microsoft Academic Search

BackgroundThe radiation-induced “bystander effect” (RIBE) was shown to occur in a number of experimental systems both in vitro and in vivo as a result of exposure to ionizing radiation (IR). RIBE manifests itself by intercellular communication from irradiated cells to non-irradiated cells which may cause DNA damage and eventual death in these bystander cells. It is known that human stem

Mykyta V. Sokolov; Ronald D. Neumann; Henning Ulrich

2010-01-01

156

Radiation-induced transient absorption in single mode optical fibers  

SciTech Connect

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.

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

1988-01-01

157

Radiation-induced damage studies of energetic materials  

Microsoft Academic Search

We present studies of synchrotron radiation-induced decomposition of PETN and TATB under conditions of high pressure, high temperature, and crystalline orientation. We have found that the decomposition rate varies dramatically under all three of these variables. The experiments were performed using white beam synchrotron radiation at the 16 BM-B and 16 BM-D sectors of the HP-CAT beamline at the Advanced

Michael Pravica; Hubertus Giefers; Zachary Quine; Edward Romano; Sean Bajar; Brian Yulga; Wenge Yang; Hans Peter Liermann; Daniel Hooks

2007-01-01

158

Aging masks detection of radiation-induced brain injury  

PubMed Central

Fractionated partial or whole-brain irradiation (fWBI) is a widely used, effective treatment for primary and metastatic brain tumors, but it also produces radiation-induced brain injury, including cognitive impairment. Radiation-induced neural changes are particularly problematic for elderly brain tumor survivors who also experience age-dependent cognitive impairment. Accordingly, we investigated, i] radiation-induced cognitive impairment, and ii] potential biomarkers of radiation-induced brain injury in a rat model of aging. Fischer 344 × Brown Norway rats received fractionated whole-brain irradiation (fWBI rats, 40 Gy, 8 fractions over 4 wk) or sham-irradiation (Sham-IR rats) at 12 months of age; all analyses were performed at 26–30 months of age. Spatial learning and memory were measured using the Morris water maze (MWM), hippocampal metabolites were measured using proton magnetic resonance spectroscopy (1H MRS), and hippocampal glutamate receptor subunits were evaluated using Western blots. Young rats (7–10 month-old) were included to control for age effects. The results revealed that both Sham-IR and fWBI rats exhibited age-dependent impairments in MWM performance; fWBI induced additional impairments in the reversal MWM. 1H MRS revealed age-dependent decreases in neuronal markers, increases in glial markers, but no detectable fWBI-dependent changes. Western blot analysis revealed age-dependent, but not fWBI-dependent, glutamate subunit declines. Although previous studies demonstrated fWBI-induced changes in cognition, glutamate subunits, and brain metabolites in younger rats, age-dependent changes in these parameters appear to mask their detection in old rats, a phenomenon also likely to occur in elderly fWBI patients >70 years of age.

Shi, Lei; Olson, John; D'Agostino, Ralph; Linville, Constance; Nicolle, Michelle M.; Robbins, Michael E.; Wheeler, Kenneth T.; Brunso-Bechtold, Judy K.

2011-01-01

159

Theory of Radiation-Induced Attenuation in Optical Fibers  

NASA Technical Reports Server (NTRS)

A new mathematical model for describing radiation-induced attenuation in optical fibers ispresented. Unlike the existing empirical power law, the new expression is dose- rate dependent andcan be used to predict low-dose-rate induced fiber loss occurring in space from the normally high-dose-rate results obtained in a ground-based laboratory. The new theory is in good agreement withthe experiment.

Liu, Duncan T. H.; Johnston, Alan R.

1993-01-01

160

Verilog-A Modeling of Radiation-Induced Mismatch Enhancement  

Microsoft Academic Search

Physical model of TID effects is embedded into BSIM3v3 model implemented using Verilog-A. Radiation-induced mismatch enhancement due to the combined action of technology variations and electrical bias difference is demonstrated by sim- ulation. It is shown that the total ionizing dose degradation of circuit components under inequivalent electric field conditions could lead to mismatch of internal circuit parameters, which results

Maxim S. Gorbunov; Igor A. Danilov; Gennady I. Zebrev; Pavel N. Osipenko

2011-01-01

161

Protection from radiation-induced pneumonitis using cerium oxide nanoparticles.  

PubMed

In an effort to combat the harmful effects of radiation exposure, we propose that rare-earth cerium oxide (CeO(2)) nanoparticles (free-radical scavengers) protect normal tissue from radiation-induced damage. Preliminary studies suggest that these nanoparticles may be a therapeutic regenerative nanomedicine that will scavenge reactive oxygen species, which are responsible for radiation-induced cell damage. The effectiveness of CeO(2) nanoparticles in radiation protection in murine models during high-dose radiation exposure is investigated, with the ultimate goal of offering a new approach to radiation protection, using nanotechnology. We show that CeO(2) nanoparticles are well tolerated by live animals, and they prevent the onset of radiation-induced pneumonitis when delivered to live animals exposed to high doses of radiation. In the end, these studies provide a tremendous potential for radioprotection and can lead to significant benefits for the preservation of human health and the quality of life for humans receiving radiation therapy. PMID:19285453

Colon, Jimmie; Herrera, Luis; Smith, Joshua; Patil, Swanand; Komanski, Chris; Kupelian, Patrick; Seal, Sudipta; Jenkins, D Wayne; Baker, Cheryl H

2009-06-01

162

Radiation induced CNS toxicity - molecular and cellular mechanisms  

PubMed Central

Radiotherapy of tumours proximal to normal CNS structures is limited by the sensitivity of the normal tissue. Prior to the development of prophylactic strategies or treatment protocols a detailed understanding of the mechanisms of radiation induced CNS toxicity is mandatory. Histological analysis of irradiated CNS specimens defines possible target structures prior to a delineation of cellular and molecular mechanisms. Several lesions can be distinguished: Demyelination, proliferative and degenerative glial reactions, endothelial cell loss and capillary occlusion. All changes are likely to result from complex alterations within several functional CNS compartments. Thus, a single mechanism responsible cannot be separated. At least four factors contribute to the development of CNS toxicity: (1) damage to vessel structures; (2) deletion of oligodendrocyte-2 astrocyte progenitors (O-2A) and mature oligodendrocytes; (3) deletion of neural stem cell populations in the hippocampus, cerebellum and cortex; (4) generalized alterations of cytokine expression. Several underlying cellular and molecular mechanisms involved in radiation induced CNS toxicity have been identified. The article reviews the currently available data on the cellular and molecular basis of radiation induced CNS side effects. ??http://www.bjcancer.com © 2001 Cancer Research Campaign

Belka, C; Budach, W; Kortmann, R D; Bamberg, M

2001-01-01

163

[Radiation-induced sequelae: toward an individual profile].  

PubMed

The impact of curative radiotherapy depends mainly on the total dose delivered homogenously in the targeted volume. Nevertheless, the dose delivery is limited by the tolerated dose of the surrounding healthy tissues. Two different side effects (acute and late) can occur during and after radiotherapy. Of particular interest are the radiation-induced sequelae due to their irreversibility and the potential impact on daily quality of life. In a population treated in one center with the same technique, it appears that individual radiosensitivity clearly exists. In the hypothesis that genetic is involved in this area of research, lymphocytes seem to be the tissue of choice due to easy accessibility. Recently, low percentage of CD4 and CD8 lymphocyte apoptosis were shown to be correlated with high grade of sequelae. In addition, recent data suggest that patients with severe radiation-induced late side effects possess four or more SNP in candidate genes (ATM, SOD2, TGFB1, XRCC1 et XRCC3) and low radiation-induced CD8 lymphocyte apoptosis in vitro. PMID:18757226

Azria, D; Belkacemi, Y; Lagrange, J-L; Chapet, O; Mornex, F; Maingon, P; Hennequin, C; Rosenstein, B; Ozsahin, M

2008-11-01

164

Identifying patients at risk for late radiation-induced toxicity.  

PubMed

The impact of curative radiotherapy depends mainly on the total dose delivered in the targeted volume. Nevertheless, the dose delivered to the surrounding healthy tissues may reduce the therapeutic ratio of many treatments. Two different side effects (acute and late) can occur during and after radiotherapy. Of particular interest are the radiation-induced late complications (LC) due to their irreversibility and the potential impact on quality of life. In one population treated with the same technique, it appears that individual radiosensitivity clearly exists. In the hypothesis that genetic is involved in this area of research, low CD4 and CD8 lymphocyte apoptosis were shown to be correlated with high grade of LC. In addition, recent data suggest that patients with severe radiation-induced LC possess 4 or more single nucleotide polymorphisms (SNPs) in candidate genes and low radiation-induced CD8 lymphocyte apoptosis in vitro. On-going studies are being analyzing the entire genome using a genome-wide association study (GWAS). PMID:20869261

Azria, D; Betz, M; Bourgier, C; Jeanneret Sozzi, W; Ozsahin, M

2012-12-01

165

Radiation-induced changes in permeability in unilamellar phospholipid liposomes.  

PubMed

Gamma-radiation-induced oxidative damage in unilamellar dipalmitoylphosphatidylcholine liposomes was investigated using a fluorescence technique. Liposomal changes in permeability induced by gamma radiation were monitored by measuring the leakage of pre-encapsulated 6-carboxyfluorescein, and alterations in lipid bilayer fluidity were determined by 1,6-diphenyl-1,3,5-hexatriene fluorescence polarization. The changes in permeability and fluidity in the bilayer were found to be dependent on the radiation dose in a biphasic fashion. The results are interpreted in terms of lipid bilayer fluidization after exposure to doses up to 1 kGy, but rigidization of the bilayer at higher doses. These results indicate a relationship between alterations in permeability and fluidity in the lipid bilayer after irradiation. The vesicles were protected significantly against radiation-induced oxidative damage in the presence of alpha-tocopherol and ascorbic acid. Radiation-induced changes in the permeability of the liposomes after exposure to gamma radiation and their modification by antioxidants indicate the involvement of a free radical mechanism in the production of damage, which may offer new insights in to the modification of cellular radiosensitivity by modulation of membrane damage. PMID:12005548

Marathe, Dipti; Mishra, K P

2002-06-01

166

Radiation-induced grain boundary segregation in austenitic stainless steels  

SciTech Connect

Radiation-induced segregation (RIS) to grain boundaries in Fe-Ni-Cr-Si stainless alloys has been measured as a function of irradiation temperature and dose. Heavy-ion irradiation was used to produce damage levels from 1 to 20 displacements per atom (dpa) at temperatures from 175 to 550{degrees}C. Measured Fe, Ni, and Cr segregation increased sharply with irradiation dose (from G to 5 dpa) and temperature (from 175 to about 350{degrees}C). However, grain boundary concentrations did not change significantly as dose or temperatures were further increased. Although interfacial compositions were similar, the width of radiation-induced enrichment or depletion profiles increased consistently with increasing dose or temperature. Impurity segregation (Si and P) was also measured, but only Si enrichment appeared to be radiation-induced. Grain boundary Si peaked at levels approaching 10 at% after irradiation doses to 10 dpa at an intermediate temperature of 325{degrees}C. No evidence of grain boundary silicide precipitation was detected after irradiation at any temperature. Equilibrium segregation of P was measured in the high-P alloys, but interfacial concentration did not increase with irradiation exposure. Comparisons to reported RIS in neutron-irradiated stainless steels revealed similar grain boundary compositional changes for both major alloying and impurity elements.

Bruemmer, S.M.; Charlot, L.A.; Vetrano, J.S.; Simonen, E.P.

1994-11-01

167

Bilateral brachial plexus injury following acute carbon monoxide poisoning  

PubMed Central

Background Carbon monoxide (CO) intoxication is a leading cause of severe neuropsychological impairments. Peripheral nerve injury has rarely been reported. It consists usually in a demyelinating polyneuropathy or mononeuropathy affecting mainly the lower limbs. Isolated involvement of both upper extremities has been described in only 4 patients related to root damage. We report the first case of bilateral brachial plexus injury following CO poisoning and review all previous CO-induced neuropathy described in literature. Case presentation After being unconscious for three hours, a 42 years old man experienced bilateral brachial weakness associated with edema of the face and the upper limbs. Neurological examination showed a brachial diplegia, distal vibratory, thermic and algic hypoesthesia, deep tendon areflexia in upper limbs. There was no sensory or motor deficit in lower extremities. No cognitive disturbances were detected. Creatine kinase was elevated. Electroneuromyogram patterns were compatible with the diagnosis of bilateral C5 D1 brachial axonal plexus injury predominant on the left side. Clinical course after hyperbaric oxygen therapy was marked by a complete recovery of neurological disorders. Conclusion Peripheral neuropathy is an unusual complication of CO intoxication. Bilateral brachial plexus impairment is exceptional. Various mechanisms have been implicated including nerve compression secondary to rhabdomyolysis, nerve ischemia due to hypoxia and direct nerve toxicity of carbon monoxide. Prognosis is commonly excellent without any sequelae.

2013-01-01

168

Rehabilitation of brachial plexus injuries in adults and children.  

PubMed

Management of brachial plexus injury sequelae is a challenging issue in neurorehabilitation. In the last decades great strides have been made in the areas of early diagnosis and surgical techniques. Conversely, rehabilitation of brachial plexus injury is a relatively unexplored field. Some critical aspects regarding brachial plexus injury rehabilitation have to be acknowledged. First, brachial plexus injury may result in severe and chronic impairments in both adults and children, thus requiring an early and long-lasting treatment. Second, nerve damage causes a multifaceted clinical picture consisting of sensorimotor disturbances (pain, muscle atrophy, muscle weakness, secondary deformities) as well as reorganization of the Central Nervous System that may be associated with upper limb underuse, even in case of peripheral injured nerves repair. Finally, psychological problems and a lack of cooperation by the patient may limit rehabilitation effects and increase disability. In the present paper the literature concerning brachial plexus injury deficits and rehabilitation in both adults and children was reviewed and discussed. Although further research in this field is recommended, current evidence supports the potential role of rehabilitation in reducing both early and long-lasting disability. Furthermore, the complexity of the functional impairment necessitates an interdisciplinary approach incorporating various health professionals in order to optimizing outcomes. PMID:23075907

Smania, N; Berto, G; La Marchina, E; Melotti, C; Midiri, A; Roncari, L; Zenorini, A; Ianes, P; Picelli, A; Waldner, A; Faccioli, S; Gandolfi, M

2012-09-01

169

Quantifying Local Radiation-Induced Lung Damage From Computed Tomography  

SciTech Connect

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.

Ghobadi, Ghazaleh; Hogeweg, Laurens E. [Department of Radiation Oncology, University Medical Center Groningen/University of Groningen, Groningen (Netherlands); Faber, Hette [Department of Radiation Oncology, University Medical Center Groningen/University of Groningen, Groningen (Netherlands); Department of Cell Biology, Section of Radiation and Stress Cell Biology, University Medical Center Groningen/University of Groningen, Groningen (Netherlands); Tukker, Wim G.J. [Department of Radiology, University Medical Center Groningen/University of Groningen, Groningen (Netherlands); Schippers, Jacobus M. [Department of Radiation Oncology, University Medical Center Groningen/University of Groningen, Groningen (Netherlands); Accelerator Department, Paul Scherrer Institut, Villigen (Switzerland); Brandenburg, Sytze [Kernfysisch Versneller Instituut, Groningen (Netherlands); Langendijk, Johannes A. [Department of Radiation Oncology, University Medical Center Groningen/University of Groningen, Groningen (Netherlands); Coppes, Robert P. [Department of Radiation Oncology, University Medical Center Groningen/University of Groningen, Groningen (Netherlands); Department of Cell Biology, Section of Radiation and Stress Cell Biology, University Medical Center Groningen/University of Groningen, Groningen (Netherlands); Luijk, Peter van, E-mail: p.van.luijk@rt.umcg.n [Department of Radiation Oncology, University Medical Center Groningen/University of Groningen, Groningen (Netherlands)

2010-02-01

170

Measurements of prompt radiation induced conductivity of Kapton.  

SciTech Connect

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.

Preston, Eric F. (ITT Corporation, Colorado Springs, CO); Zarick, Thomas Andrew; Sheridan, Timothy J.; Hartman, E. Frederick; Stringer, Thomas Arthur (ITT Corporation, Colorado Springs, CO)

2010-10-01

171

Radiation-induced bystander signalling in cancer therapy  

PubMed Central

Our understanding of how radiation kills normal and tumour cells has been based on an intimate knowledge of the direct induction of DNA damage and its cellular consequences. What has become clear is that, as well as responses to direct DNA damage, cell–cell signalling — known as the bystander effect — mediated through gap junctions and inflammatory responses may have an important role in the response of cells and tissues to radiation exposure and also chemotherapy agents. This Review outlines the key aspects of radiation-induced intercellular signalling and assesses its relevance for existing and future radiation-based therapies.

Prise, Kevin M.; O'Sullivan, Joe M.

2010-01-01

172

Radiation-induced morphoea treated with UVA-1 phototherapy.  

PubMed

Morphoea is a localized inflammatory disorder of the dermis and subcutaneous fat and radiotherapy is a rarely reported cause (estimated incidence of 2 per 1000). Morphoea is commonly mistaken for an inflammatory recurrence of breast cancer, resulting in unnecessary investigations and treatment. We report the case of a 40-year-old woman who developed radiation-induced morphoea of the breast 7 months following adjuvant radiotherapy. She was treated with topical and systemic steroids as well as psoralen plus ultraviolet (UV)A before proceeding to UVA1 phototherapy. We also review the literature and discuss other management options. PMID:24890985

Lim, D; Johnston, S; Novakovic, L; Fearfield, L

2014-07-01

173

Radiation-induced differential optical absorption of metal nanoparticles  

NASA Astrophysics Data System (ADS)

A method of measuring the temperature of metal nanoparticles under ion bombardment is proposed. Optical absorption in the range of the surface plasmon resonance of metal nanoparticles was measured during implantation of 3 MeV Cu2+ ions into silica glass to derive a difference in optical absorption between beam on and off regimes. The radiation-induced differential (RD) spectra were similar to the spectra of thermomodulation (TM) and quite different from the spectra of nonlinear optical response measured by the pump-probe method. Increasing amplitude of RD and TM spectra was assigned to an increase of lattice temperature of Cu nanoparticles.

Plaksin, Oleg; Takeda, Yoshihiko; Amekura, Hiroshi; Kishimoto, Naoki

2006-05-01

174

Internally consistent model for radiation-induced void swelling  

SciTech Connect

Most previous analytical models for radiation-induced void swelling employed reaction rate theory in which all concentrations were averaged out. Here a unified, internally consistent analytical approach is presented which incorporates the presence of dislocations, voids, and grain boundaries each with their own spatially varying diffusional fields. The results show large variations in sink strength Z-factors, usually treated as constants, significant variations in the void swelling bias factor, and quantitative levels of bias about an order of magnitude larger than most previous estimates. Good qualitative agreement is shown with available data, consistent with current concepts of close-pair annihilation in high-energy damage cascades.

Nichols, F.A.; Liu, Y.Y.

1981-01-01

175

[Interest of blood markers in predicting radiation-induced toxicity].  

PubMed

The oncologic outcome and the total dose are highly correlated with the treatment by ionizing radiation. The dose increase (total or per fraction) may provoke late-side effects that are potentially irreversible. The radiation-induced CD8 lymphocyte apoptotic value and the molecular modifications within the lymphocyte are capable of predicting the level of risk of developing late-side effects after curative intent radiotherapy. In this review, we present the different blood assays in this setting and discuss the current possibilities of researches, namely those involving the proteomic process. PMID:21676639

Lacombe, J; Solassol, J; Coelho, M; Ozsahin, M; Azria, D

2011-08-01

176

Radiation-induced segregation in candidate fusion-reactor alloys  

SciTech Connect

The effect of radiation on surface segregation of minor and impurity elements has been studied in four candidate fusion reactor alloys. Radiation induced surface segregation of phosphorus was found in both 316 type stainless steel and in Nimonic PE-16. Segregation and depletion of the other alloying elements in 316 stainless steel agreed with that reported by other investigators. Segregation of nitrogen in ferritic HT-9 was enhanced by radiation but no phosphorus segregation was detected. No significant radiation enhanced or induced segregation was observed in a Ti-6Al-4V alloy. The results indicate that radiaton enhanced grain boundary segregation could contribute to the embrittlement of 316 SS and PE-16.

Brimhall, J.L.; Baer, D.R.; Jones, R.H.

1981-07-01

177

Interpretation and significance of ankle-brachial systolic pressure index.  

PubMed

The ankle-brachial systolic pressure index (ABI) is an underutilized, easy-to-perform, physiologic test to diagnosis atherosclerotic lower-limb arterial occlusive disease. Testing requires a sphygmomanometer and continuous-wave Doppler probe to measure the ratio of ankle and brachial systolic blood pressures. The ABI measurement has been standardized by use of the highest ankle and brachial systolic pressure for the calculation; abnormal threshold value is ?0.9. The ABI is used to diagnosis and screen for peripheral arterial disease, which is a surrogate marker of atherosclerosis and a predictor of cardiovascular events. A lower ABI value correlates with severity of limb ischemia and decreased survival. Measurement of ABI is recommended as the initial diagnostic test for patients with exertional leg pain (claudication), to assess the healing potential of foot lesions, after blunt extremity trauma to detect occult arterial injury, and as part of the routine health assessment of patients with diabetes and peripheral arterial disease. PMID:24636605

Ko, Sae Hee; Bandyk, Dennis F

2013-01-01

178

Characterization of radiation-induced emesis in the ferret  

SciTech Connect

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.

King, G.L.

1988-01-01

179

Characterization of radiation-induced emesis in the ferret  

SciTech Connect

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.

King, G.L.

1988-06-01

180

Should Cancer Survivors Fear Radiation-Induced Sarcomas?  

PubMed Central

Purpose/Results. Ionizing radiation is carcinogenic and the induction of a second malignancy is a serious potential long-term complication of radiotherapy. The incidence of radiation-induced sarcomas was evaluated from many large epidemiological surveys of long-term cancer survivors reported in the literature over the past 30 years and only one case was found for every 1000 patients irradiated. Discussion. Although greater numbers of cancer patients are receiving radical radiotherapy and surviving free of disease for longer intervals, cases of radiation-induced sarcomas are rare and should not deter patients from accepting radiotherapy as treatment for curable cancers. With improvements in the administration of radiotherapy over the past two decades which are resulting in less damage to bone and soft tissues, it is likely that fewer cases of this condition will be seen in the future. If these sarcomas are diagnosed early, long-term survival can be achieved with surgical excision and possibly re-irradiation, as occurs in other types of sarcomas.

1997-01-01

181

Simvastatin attenuates radiation-induced tissue damage in mice.  

PubMed

The aim of this study was to investigate the protective effect of simvastatin against radiation-induced tissue injury in mice. Mice were radiated with 4 Gy or 8 Gy after 20 mg/kg/d simvastatin treatment over 2 weeks. Morphological changes were observed in the jejunum and bone marrow, and apoptotic cells were determined in both tissues. Peripheral blood cells were counted, and the superoxide dismutase (SOD) activity and the malondialdehyde (MDA) level in tissues of both thymus and spleen were measured. Compared with the radiation-only group, 20 mg/kg/d simvastatin administration significantly increased the mean villi height and decreased apoptotic cells in jejunum tissue, and stimulated regeneration and reduced apoptotic cells in bone marrow. Peripheral blood cell analysis revealed that simvastatin treatment induced a larger number of red blood cells and increased the hemoglobin level present after 4 Gy of radiation. Interestingly, it was also found that the number of peripheral endothelial progenitor cells was markedly increased following simvastatin administration. Antioxidant determination for tissues displayed that simvastatin therapy increased the SOD activity after both 4 and 8 Gy of radiation, but only decreased the MDA level after 4 Gy. Simvastatin ameliorated radiation-induced tissue damage in mice. The radioprotective effect of simvastatin was possibly related to inhibition of apoptosis and improvement of oxygen-carrying and antioxidant activities. PMID:24105712

Zhao, Xinbin; Yang, Hong; Jiang, Guojun; Ni, Min; Deng, Yaping; Cai, Jian; Li, Zhangpeng; Shen, Fuming; Tao, Xia

2014-03-01

182

Squamous cell carcinoma antigen suppresses radiation-induced cell death  

PubMed Central

Previous study has demonstrated that squamous cell carcinoma antigen (SCCA) 1 attenuates apoptosis induced by TNF?, NK cell or anticancer drug. In this study, we have examined the effect of SCCA2, which is highly homologous to SCCA1, but has different target specificity, against radiation-induced apoptosis, together with that of SCCA1. We demonstrated that cell death induced by radiation treatment was remarkably suppressed not only in SCCA1 cDNA-transfected cells, but also in SCCA2 cDNA-transfected cells. In these transfectants, caspase 3 activity and the expression of activated caspase 9 after radiation treatment were suppressed. Furthermore, the expression level of phosphorylated p38 mitogen-activated protein kinase (p38 MAPK) was suppressed compared to that of the control cells. The expression level of upstream stimulator of p38 MAPK, phosphorylated MKK3/MKK6, was also suppressed in the radiation-treated cells. Thus, both SCCA1 and SCCA2 may contribute to survival of the squamous cells from radiation-induced apoptosis by regulating p38 MAPK pathway. © 2001 Cancer Research Campaign http://www.bjcancer.com

Murakami, A; Suminami, Y; Hirakawa, H; Nawata, S; Numa, F; Kato, H

2001-01-01

183

Radiation induced corrosion of copper for spent nuclear fuel storage  

NASA Astrophysics Data System (ADS)

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.

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

2013-11-01

184

Radiation-induced skin carcinomas of the head and neck  

SciTech Connect

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.

Ron, E.; Modan, B.; Preston, D.; Alfandary, E.; Stovall, M.; Boice, J.D. Jr. (National Cancer Institute, Bethesda, MD (USA))

1991-03-01

185

Swelling and radiation-induced segregation in austentic alloys  

NASA Astrophysics Data System (ADS)

To elucidate the relationship between radiation-induced segregation and swelling in austenitic stainless steels, a series of alloys were irradiated with 3.2 MeV protons to doses of 0.5 and 1.0 dpa at 400 °C. Three alloy series were irradiated, the first to examine the effect of bulk nickel in Fe-16-18Cr- xNi, the second to determine the effect of Mo and P in an Fe-16Cr-13Ni base alloy, and the third to examine the effect of oversized solute Zr addition to an Fe-18Cr-0.5Ni alloy. The addition of nickel in Fe-16-18Cr- xNi caused a significant decrease in swelling and increase in segregation. The addition of Mo+P to Fe-16Cr-13Ni eliminated swelling and reduced segregation. The addition of Zr to Fe-18Cr-9.5Ni decreased swelling and altered the segregation. Comparison of swelling with changes in lattice parameter and shear modulus caused by the segregation showed that swelling correlates well with the decreases in lattice parameter caused by radiation-induced segregation. Those alloys whose segregation decreased the lattice parameter the greatest showed the lowest swelling. These results are consistent with theoretical predictions made by Wolfer.

Allen, T. R.; Cole, J. I.; Gan, J.; Was, G. S.; Dropek, R.; Kenik, E. A.

2005-06-01

186

Radiation-induced transmissable chromosomal instability in haemopoietic stem cells  

NASA Astrophysics Data System (ADS)

Heritable radiation-induced genetic alterations have long been assumed to be ``fixed'' within the first cell division. However, there is a growing body of evidence that a considerable fraction of cells surviving radiation exposure appear normal, but a variety of mutational changes arise in their progeny due to a transmissible genomic instability. In our investigations of G-banded metaphases, non-clonal cytogenetic aberrations, predominantly chromatid-type aberrations, have been observed in the clonal descendants of murine and human haemopoietic stem cells surviving low doses (~1 track per cell) of alpha-particle irradiations. The data are consistent with a transmissible genetic instability induced in a stem cell resulting in a diversity of chromosomal aberrations in its clonal progeny many cell divisions later. Recent studies have demonstrated that the instability phenotype persists in vivo and that the expression of chromosomal instability has a strong dependence on the genetic characteristics of the irradiated cell. At the time when cytogenetic aberrations are detected, an increased incidence of hprt mutations and apoptotic cells have been observed in the clonal descendants of alpha-irradiated murine haemopoietic stem cells. Thus, delayed chromosomal abnormalities, delayed cell death by apoptosis and late-arising specific gene mutations may reflect diverse consequences of radiation-induced genomic instability. The relationship, if any, between these effects is not established. Current studies suggest that expression of these delayed heritable effects is determined by the type of radiation exposure, type of cell and a variety of genetic factors.

Kadhim, M. A.; Wright, E. G.

187

Radiation-induced defect centers in glass ceramics  

SciTech Connect

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.

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

1989-01-15

188

Low Estimated Glomerular Filtration Rate Is a Major Determinant of Low Ankle-Brachial Index and Toe-Brachial Index in Type 2 Diabetes  

Microsoft Academic Search

We enrolled 1461 Taiwanese type 2 diabetic outpatients with ankle-brachial index (ABI) and toe-brachial index (TBI) examinations, excluding participants with history of stroke, end-stage renal disease, malignancy, acute myocardial infarction, amputation, and overt calcification of the lower limbs (ABI >1.3). Ankle-brachial index values <0.9 were found in 2.8% of the patients and 5.7% had TBI <0.6. Estimated glomerular filtration rate

Yi-Jing Sheen; Jainn-Liang Lin; I-Te Lee; Yuan-Nian Hsu; Tsai-Chung Li; Wayne Huey-Herng Sheu

2012-01-01

189

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

NASA Astrophysics Data System (ADS)

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

Matsumoto, H.; Ohnishi, T.

190

Radiation Induced Sarcoma of Oral Cavity-A Rare Case Report and a Short Review  

PubMed Central

Radiation - Induced Sarcomas(RIS) are rare clinical entity. They arise from the previously irradiated areas with a prolonged latency period. In this case report we present a rare case of radiation induced sarcoma with a brief review of literature. We report radiation-induced sarcoma in a 67–year–old male, involving the left Retromolar Trigone region following treatment of squamous cell carcinoma of tongue with wide excision, neck dissection and post-operative radiation. Diagnosis of radiation induced sarcoma was confirmed by history, latency period and biopsy.

Ganesan, Sivaraman; Iype, Elizabeth Mathew; Kapali, Aravind S.; S., Renu

2013-01-01

191

Neurography of the brachial plexus in the thoracic outlet syndrome  

Microsoft Academic Search

Neurography of the brachial plexus was carried out in 180 patients with suspected thoracic outlet syndrome and in 30 normal subjects. In the thoracic outlet syndrome, abnormalities were found in 85% of suspected cases. Narrowing was seen in the scalenus triangle (30%), in the costoclavicular-space (75%) and at the subcoracoid level (6%). Translucent lines were present in 53%, and in

M. Takeshita; H. Minamikawa; H. Iwamoto; N. Takagishi

1991-01-01

192

Axillary Brachial Plexus Blockade for the Reflex Sympathetic Dystrophy Syndrome.  

ERIC Educational Resources Information Center

Reflex sympathetic dystrophy syndrome (RSD) is a neurogenic pain syndrome characterized by pain, vasomotor and dystrophic changes, and often motor impairments. This study evaluated the effectiveness of brachial plexus blockade with local anaesthetic drugs as a treatment for this condition. Three patients responded well; three did not. (DB)

Ribbers, G. M.; Geurts, A. C. H.; Rijken, R. A. J.; Kerkkamp, H. E. M.

1997-01-01

193

Ultrasonographic Findings of the Axillary Part of the Brachial Plexus  

Microsoft Academic Search

In this prospective study we sought to determine ana- tomic variations of the main brachial plexus nerves in the axilla and upper arm via high-resolution ultra- sonography (US) examination. Positions of nerves were studied via US in three sectional levels of the upper arm in 69 healthy volunteers (31 men and 38 women, me- dian age 28 yr). Analysis was

Gerald Retzl; Stephan Kapral; Manfred Greher; Walter Mauritz

2001-01-01

194

Radiation-induced transient attenuation of PCS fiber  

SciTech Connect

Some applications of optical fibers require their exposure to intense radiation fields. This exposure can potentially degrade performance of a fiber data link. Research at Los Alamos National Laboratory has recently concentrated on development of an understanding of such radiation effects at short times, less than 100 ns. In previous papers we have identified a particular type of fiber, ITT plastic-clad-silica (PCS) with Suprasil core as optimum for short time radiation-induced attenuation, but that work used very large doses of ionizing radiation, close to 1 Mrad. For these high dose exposures, moderate success in understanding the transient nature of the attenuation was realized with a geminate recombination model. In this paper, we report further studies with ITT PCS fiber over a range of doses and wavelengths. Data on other PCS fibers is included that provide performance comparable to the ITT product. Comparison to several fluorsilicate fibers is also included.

Lyons, P.B.; Looney, L.D.; Ogle, J.W.

1983-01-01

195

Solar radiation induced rotational bursting of interplanetary particles  

NASA Technical Reports Server (NTRS)

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.

Sparrow, J. G.

1975-01-01

196

Radiation-induced hydroperoxidation of oleic acid on silica gel  

NASA Astrophysics Data System (ADS)

Radiation-induced hydroperoxidation of oleic acid in bulk liquid, in multiple liquid layers on glass and in silica gel coated with O1 proceed by a chain mechanism. Two propagation steps in the formation of OlOOH could be identified in bulk liquid, as well as in adsorbed layers: reaction with oxygen and chain transfer reaction. Consequently, radiation chemical yields of hydroperoxidation, G(OlOOH), are influenced by both, the availability of oxygen and by the presence of chain-breaking antioxidants. Besides scavenging precursors to OlOOH, ?-tocopherol also reacts with OlOOH formed in monolayers by irradiation. Adsorbed layers of oleic acid behave as two-dimensional liquids.

Katušin-Ražem, Branka; Ražem, Dušan

1996-03-01

197

Radiation induced grafting of acrylic acid onto extruded polystyrene surface  

NASA Astrophysics Data System (ADS)

Polystyrene materials with good solubility in liquid scintillation cocktails are used to wipe off different types of surfaces in order to determine the tritium removable contamination with the help of a liquid scintillation counter. This paper analyses hydrophilic surface modifications by radiation induced grafting of acrylic groups onto extruded polystyrene plates. Two grafting methods were used: (a) exposure of extruded polystyrene plates, immersed in aqueous acrylic acid solution, to a gamma radiation of a Co-60 source, and (b) exposure of extruded polystyrene plates to a Co-60 source, followed by the immersion of extruded polystyrene plates in aqueous acrylic acid solution. The grafting of acrylic was proved by IR spectrometry and by radiometric methods using acrylic acid labelled with tritium.

Fugaru, Viorel; Bubueanu, George; Tuta, Catalin

2012-09-01

198

An internally consistent model for radiation-induced void swelling  

SciTech Connect

Most previous analytical models for radiation-induced void swelling employed reaction rate theory in which all concentrations were ''averaged out.'' The loss terms for use in such models were then usually obtained by separate, single-cell diffusion analyses which introduced various inconsistencies and uncertainties. Presented here is a unified, internally consistent analytical approach which incorporates, for the first time, the presence of dislocations, voids, and grain boundaries each with their own spatially varying diffusional fields. The results show large variations in sink strength Z-factors, usually treated as constants, significant variations in the void swelling bias factor, and quantitative levels of bias about an order of magnitude larger than most previous estimates. Good qualitative agreement is shown with available data, consistent with current concepts of close-pair annihilation in high-energy damage cascades.

Nichols, F.A.; Liu, Y.Y.

1981-01-01

199

Radiation-induced formation of cavities in amorphous germanium  

SciTech Connect

Prethinned polycrystalline Ge TEM samples were irradiated with 1.5 MeV Kr{sup +} ions at room temperature while structural and morphological changes were observed {ital in} {ital situ} in the Argonne High Voltage Electron Microscope-Tandem Facility. After a Kr{sup +} dose of 1.2{times}10{sup 14} ions/cm{sup 2}, the irradiated Ge was completely amorphized. A high density of small void-like cavities was observed after a Kr{sup +} dose of 7{times}10{sup 14} ions/cm{sup 2}. With increasing Kr{sup +} ion dose, these cavities grew into large holes transforming the irradiated Ge into a sponge-like porous material after 8.5{times}10{sup 15} ions/cm{sup 2}. The radiation-induced nucleation of void-like cavities in amorphous material is astonishing, and the final structure of the irradiated Ge with enormous surface area may have potential applications.

Wang, L.M.; Birtcher, R.C. (Materials Science Division, Argonne National Laboratory, Argonne, Illinois 60439 (US))

1989-12-11

200

Radiation induced crystallinity damage in poly( L-lactic acid)  

NASA Astrophysics Data System (ADS)

The radiation-induced crystallinity damage in poly( L-lactic acid) (PLLA) in the presence of air and in vacuum, is studied. From the heat of fusion enthalpy values of gamma irradiated samples, some changes on the thermal properties were determined. To identify these changes, first the glass transition temperature ( Tg) of L-lactic acid polymers irradiated to various doses in air and vacuum have been investigated and it is found that it is independent of irradiation atmosphere and dose. The fraction of damaged units of PLLA per unit of absorbed energy has been measured. For this purpose, SAXS and differential scanning calorimetry methods were used, and the radiation yield of number of damaged units ( G(- u)) is found to be 0.74 and 0.58 for PLLA samples irradiated in vacuum and air, respectively.

Kanto?lu, Ömer; Güven, Olgun

2002-12-01

201

Mechanisms of radiation-induced sensorineural hearing loss and radioprotection.  

PubMed

Patients that receive radiotherapy are at risk of late sensorineural hearing loss when the inner ear is included within the radiation field. Preclinical and human temporal bone studies have shown that there is differential damage to cochlear structures depending on the amount of dose delivered to the inner ear. In vitro studies have suggested that reactive oxygen species (ROS) are the main initial actors in radiation-induced damage. The interaction of ROS with different cellular components can result in different apoptotic pathways. Therefore, approaches to radioprotection are mainly aimed to reduce ROS production through antioxidants. This review summarizes recent research in the field that can improve the understanding and boost preventive efforts of this adverse effect. PMID:24650954

Mujica-Mota, Mario A; Lehnert, Shirley; Devic, Slobodan; Gasbarrino, Karina; Daniel, Sam J

2014-06-01

202

Imaging for Assessment of Radiation-Induced Normal Tissue Effects  

SciTech Connect

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.

Jeraj, Robert, E-mail: rjeraj@wisc.ed [University of Wisconsin, Madison, WI (United States); Cao Yue; Ten Haken, Randall K. [University of Michigan, Ann Arbor, MI (United States); Hahn, Carol [Duke University, Durham, NC (United States); Marks, Lawrence [Duke University, Durham, NC (United States); University of North Carolina, Chapel Hill, NC (United States)

2010-03-01

203

Probiotic Therapy in Radiation-Induced Intestinal Injury and Repair  

PubMed Central

Intestinal injury from ionizing radiation is a clinically important entity, as enteritis symptoms occur commonly after radiotherapy for pelvic malignancies. Preventative or therapeutic options for radiation enteritis are mostly unsatisfactory; however, available data suggests that probiotic bacteria—those which confer health benefit—may have therapeutic value. Previous reports from both human trials and animal models have evaluated various end points for probiotic usage in limiting radiation-associated intestinal damage. Newer data suggests that particular probiotics and/or their secreted or derived bacterial products may have unique radioprotective properties. We will review the area with a focus on new developments surrounding probiotic therapy in radiation-induced intestinal injury and repair.

Ciorba, Matthew A.; Stenson, William F.

2014-01-01

204

Dose-dependent radiation-induced hypotension in the canine  

SciTech Connect

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.

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

1986-01-01

205

Radiation-induced polymerization for the immobilization of penicillin acylase  

SciTech Connect

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.

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

1987-06-01

206

Pyridoxamine protects intestinal epithelium from ionizing radiation-induced apoptosis  

PubMed Central

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.

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

2009-01-01

207

Radiation-induced degradation of 4-chloroaniline in aqueous solution  

NASA Astrophysics Data System (ADS)

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.

Sánchez, M.; Wolfger, H.; Getoff, N.

2002-12-01

208

Modulation of radiation-induced hemopoietic suppression by acute thrombocytopenia  

SciTech Connect

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

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

1985-01-01

209

Radiation-induced leukemia: Comparative studies in mouse and man  

SciTech Connect

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.

Haas, M.

1991-01-01

210

Radiation Induces Osteogenesis in Human Aortic Valve Interstitial Cells  

PubMed Central

Objective Irradiation of the chest or chest wall has been shown to caause calcific aortic stenosis. However, the mechanisms are unknown. Aortic valve interstitial cells (AVICs) have been implicated in the pathogenesis of aortic stenosis; they have been shown to change from the phenotype of a myofibroblast to an osteoblast-like cell. We therefore hypothesized that irradiation of human AVICs induces an osteogenic phenotype. In isolated human AVICs, our purpose was to determine the effect of irradiation on the production of osteogenic factors: (a) bone morphogenetic protein-2 (BMP-2) (b) osteopontin (OPN) (c) alkaline phosphatase (ALP), and (d) the transcription factor Runx2. Methods Human AVICs were isolated from normal aortic valves obtained from explanted hearts of patients undergoing cardiac transplantation (n=4) and grown in culture. The cells were grown to confluence, irradiated with 10 Gy using a cesium-137 irradiator and then lysed 24 hours following irradiation. Cell lysates were analyzed via immunoblot and densitometry for BMP-2, OPN, ALP and Runx2. Statistics were by ANOVA. P < 0.05 was significant. Results Irradiation induced an osteogenic phenotype in human AVICs. Irradiation induced a 2-fold increase in BMP-2, a 7-fold increase in OPN, a 3-fold increase in ALP, and a 2-fold increase in Runx2. Conclusions Radiation induces an osteogenic phenotype in human AVICs. The irradiated cells had significantly increased expression of the osteogenic factors BMP-2, OPN, ALP and Runx2. These data offer mechanistic insight into the pathogenesis of radiation-induced valvular heart disease.

Nadlonek, Nicole A; Weyant, Michael J; Yu, Jessica A; Cleveland, Joseph C; Reece, T Brett; Meng, Xianzhong; Fullerton, David A.

2012-01-01

211

Ion beam induced luminescence: Relevance to radiation induced bystander effects  

NASA Astrophysics Data System (ADS)

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

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

2012-10-01

212

An Amino Acid Mixture Mitigates Radiation-induced Gastrointestinal Toxicity.  

PubMed

Electrolyte and nutrient absorption occur in villous epithelial cells. Radiation often results in reduced electrolyte and nutrient absorption, which leads to gastrointestinal toxicity. Therefore, the authors studied: (1) radiation-induced changes in glucose and amino acid absorption across ileal tissues and (2) the effect of amino acid mixtures on absorptive capacity. NIH Swiss mice were irradiated (0, 1, 3, 5, or 7 Gy) using a Cs source at 0.9 Gy min. Transepithelial short circuit current (Isc), dilution potential, and isotope flux determinations were made in Ussing chamber studies and correlated to plasma endotoxin and IL-1? levels. Amino acids that increased electrolyte absorption and improved mucosal barrier functions were used to create a mitigating amino acid mixture (MAAM). The MAAM was given to mice via gastric gavage; thereafter, body weight and survival were recorded. A significant decrease in basal and glucose-stimulated sodium absorption occurred after 0, 1, 3, 5, and 7 Gy irradiation. Ussing chamber studies showed that paracellular permeability increased following irradiation and that the addition of glucose resulted in a further increase in permeability. Following irradiation, certain amino acids manifested decreased absorption, whereas others were associated with increased absorption. Lysine, aspartic acid, glycine, isoleucine, threonine, tyrosine, valine, tryptophan, and serine decreased plasma endotoxins were selected for the MAAM. Mice treated with the MAAM showed increased electrolyte absorption and decreased paracellular permeability, IL-1? levels, and plasma endotoxin levels. Mice treated with MAAM also had increased weight gain and better survival following irradiation. The MAAM has immediate potential for use in mitigating radiation-induced acute gastrointestinal syndrome. PMID:24776907

Yin, Liangjie; Vijaygopal, Pooja; Menon, Rejeesh; Vaught, Lauren A; Zhang, Mei; Zhang, Lurong; Okunieff, Paul; Vidyasagar, Sadasivan

2014-06-01

213

Radiation-induced luminescence in terbium-doped silicate glasses  

NASA Astrophysics Data System (ADS)

The purpose of this study is to characterize radiation- induced luminescence of terbium-doped silicate glasses. Experiments performed investigated the optical properties, isothermal time-evolution, and temperature dependence of the radiation-induced luminescence of two commercially available terbium-doped glasses. A problem common to this type of glass is the persistent luminescence, or afterglow, that occurs following the end of excitation from an external source of radiation. While the processes that govern characteristic luminescence of rare earth ions, including terbium, are well understood, the processes that give rise to afterglow in doped glasses are not. Identifying the source of long-term luminescence is essential for controlling problems that may arise from practical applications of luminescent glasses. It was determined that the stimulation of terbium fluorescence is the result of direct excitation from the external radiation source, and indirect excitation from the delayed recombination of charge carriers releasing from traps in the host glass. The range of trap depths is found to be well represented by quasi-continuous distribution functions. The characteristic decay time during the initial response of both glasses studied is approximately 3.5 milliseconds. Decay of the afterglow was observed to persist for several hours, depending on the acquired dose of radiation. Comparison of the response to x-rays and ultraviolet radiation yielded the same results, indicating that the same processes are involved in producing afterglow for both cases. This result suggests a more efficient means of characterizing scintillating glasses by using ultraviolet lasers instead of x-rays.

West, Michael Stuart

1997-12-01

214

Radiation induces aerobic glycolysis through reactive oxygen species  

PubMed Central

Background and purpose Although radiation induced reoxygenation has been thought to increase radiosensitivity, we have shown that its associated oxidative stress can have radioprotective effects, including stabilization of the transcription factor hypoxia inducible factor 1 (HIF-1). HIF-1 is known to regulate many of the glycolytic enzymes, thereby promoting aerobic glycolysis, which is known to promote treatment resistance. Thus, we hypothesized that reoxygenation after radiation would increase glycolysis. We previously showed that blockade of oxidative stress using a superoxide dismutase (SOD) mimic during reoxygenation can downregulate HIF-1 activity. Here we tested whether concurrent use of this drug with radiotherapy would reduce the switch to a glycolytic phenotype. Materials and methods 40 mice with skin fold window chambers implanted with 4T1 mammary carcinomas were randomized into (1) no treatment, (2) radiation alone, (3) SOD mimic alone, and (4) SOD mimic with concurrent radiation. All mice were imaged on the ninth day following tumor implantation (30 h following radiation treatment) following injection of a fluorescent glucose analog, 2-[N-(7-nitrobenz-2-oxa-1,3-diaxol-4-yl)amino]-2-deoxyglucose (2-NBDG). Hemoglobin saturation was measured by using hyperspectral imaging to quantify oxygenation state. Results Mice treated with radiation showed significantly higher 2-NBDG fluorescence compared to controls (p = 0.007). Hemoglobin saturation analysis demonstrated reoxygenation following radiation, coinciding with the observed increase in glycolysis. The concurrent use of the SOD mimic with radiation demonstrated a significant reduction in 2-NBDG fluorescence compared to effects seen after radiation alone, while having no effect on reoxygenation. Conclusions Radiation induces an increase in tumor glucose demand approximately 30 h following therapy during reoxygenation. The use of an SOD mimic can prevent the increase in aerobic glycolysis when used concurrently with radiation, without preventing reoxygenation.

Zhong, Jim; Rajaram, Narasimhan; Brizel, David M.; Frees, Amy E.; Ramanujam, Nirmala; Batinic-Haberle, Ines; Dewhirst, Mark W.

2013-01-01

215

NF-?B signaling modulates radiation?induced microglial activation.  

PubMed

Microglial activation has been suggested to be associated with the incidence of radiation-induced brain injury. The present study investigated the molecular mechanism(s) involved in radiation-induced activation of the microglia. Mouse microglial BV-2 cells were exposed to different doses of radiation. The release of inflammatory factors was evaluated by enzyme-linked immunosorbent assay and real-time reverse transcriptase polymerase chain reaction. Protein expression was determined by immunocytochemistry and immunoblotting. Microglial activation was induced by radiation [>16 Gray (Gy)]. Activated cells exhibited a stouter spherical morphology and the levels of ionized calcium-binding adapter molecule-1 and CD68 were considerably upregulated. The generation of inflammatory factors, including interleukin-1? (IL-1?), tumor necrosis factor-? (TNF-?), IL-6, toll?like receptor 8 (TLR-8) and cyclooxygenase 2 (COX-2), was increased and peaked at either 3 or 6 h after radiation treatment. Phosphorylated ?-histone 2A, member X (?-H2AX), which facilitates DNA double-strand breaks (DSBs), was upregulated at 3 h post-radiation treatment. This was accompanied by the nuclear translocation of the nuclear factor-?B (NF-?B) p65 subunit. Moreover, 3 h following radiation treatment, the NF-?B essential modulator (NEMO) was markedly elevated, whereas the NF-?B regulatory inhibitor-? (I?B-?) was considerably decreased. Our results demonstrate that the NF-?B signaling pathway may trigger microglial activation and release of inflammatory factors following irradiation. These findings may provide valuable insight into understanding the molecular mechanism(s) involved in brain injury induced by radiation therapy. PMID:24756575

Xue, Jun; Dong, Ji-Hua; Huang, Guo-Dong; Qu, Xiao-Fei; Wu, Gang; Dong, Xiao-Rong

2014-06-01

216

Environmental applications of radiation-induced defects in clay minerals  

NASA Astrophysics Data System (ADS)

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 ? 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.

Allard, T.

2011-12-01

217

Factors influencing the yield of radiation induced electron spin resonance (ESR) signal in lamb bones  

Microsoft Academic Search

Irradiation treatment of bone-in meat chunks induced a characteristic ESR signal in the bone tissue. Effect of various processing parameters such as bone type, absorbed radiation dose, irradiation temperature, cooking prior to irradiation and post irradiation cooking on the intensity of radiation induced ESR signal was studied. It was observed that intensity of radiation induced signal was higher in leg

S. P Chawla; Paul Thomas; D. R Bongirwar

2002-01-01

218

Deep Level Transient Spectroscopy Technique to Analyze Radiation Induced Defects in Power Transistors  

SciTech Connect

Deep Level Transient Spectroscopy (DLTS) technique is useful tool to study process and radiation induced defects in semiconductor materials and devices. The different types of radiation induced trap levels in the collector-base depletion region of the transistors were studied by DLTS technique.

Prakash, A. P. Gnana [Department of Studies in Physics, University of Mysore, Manasagangotri, Mysore, Karnataka-570006 (India)

2011-07-15

219

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

SciTech Connect

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.

Kandasamy, S.B.; Hunt, W.A. (Armed Forces Radiobiology Research Institute, Bethesda, MD (USA))

1990-01-01

220

Involvement of Prostaglandins and Histamine in Radiation-Induced Temperature Responses in Rats.  

National Technical Information Service (NTIS)

Exposure of rats to Gy of gamma radiation induced hypothermia, whereas exposure to 20-150 Gy produced hypothermia. Since radiation exposure included the release of prostaglandins (PGs) and histamine, the role of PGs and histamine in radiation-induced temp...

S. B. Kandasamy W. A. Hunt

1990-01-01

221

Early hyperbaric oxygen therapy improves outcome for radiation-induced hemorrhagic cystitis  

Microsoft Academic Search

ObjectivesTo assess the clinical factors that affect the efficacy of hyperbaric oxygen (HBO2) therapy in treating radiation-induced hemorrhagic cystitis. HBO2 therapy is an effective treatment for radiation-induced hemorrhagic cystitis, with reported response rates ranging from 76% to 100%.

Kian Tai Chong; Neil B. Hampson; John M. Corman

2005-01-01

222

Deep Level Transient Spectroscopy Technique to Analyze Radiation Induced Defects in Power Transistors  

NASA Astrophysics Data System (ADS)

Deep Level Transient Spectroscopy (DLTS) technique is useful tool to study process and radiation induced defects in semiconductor materials and devices. The different types of radiation induced trap levels in the collector-base depletion region of the transistors were studied by DLTS technique.

Prakash, A. P. Gnana

2011-07-01

223

Radiation-induced chondrosarcoma of the maxilla 7-year after combined chemoradiation for tonsillar lymphoma.  

PubMed

Radiation-induced sarcoma is a rare complication of radiation therapy. We report a case of radiation-induced chondrosarcoma of the maxilla. An 80-year-old Persian woman developed radiation-induced chondrosarcoma of the left maxilla 7 years after combined chemotherapy and external beam radiation therapy for the Ann Arbor stage IE malignant lymphoma of the right tonsil. She underwent suboptimal tumour resection and died due to extensive locoregional disease 8 months later. An English language literature search of Medline using the terms chondrosarcoma, radiation-induced sarcoma and maxilla revealed only one earlier reported case. We describe the clinical and pathological features of this case and review the literature on radiation-induced sarcomas. PMID:15377806

Mohammadianpanah, M; Gramizadeh, B; Omidvari, Sh; Mosalaei, A

2004-01-01

224

Increased radiosensitivity and radiation-induced apoptosis in SRC-3 knockout mice  

PubMed Central

Steroid receptor coactivator-3 (SRC-3), a multifunctional transcriptional coactivator, plays an important role in regulation of cell apoptosis in chemoresistant cancer cells. However, its role in radiation-induced apoptosis in hematopoietic cells is still unclear. In this study, we used SRC-3 knockout (SRC-3-/-) mice to assess the role of SRC-3 in radiation-induced hematopoietic injury in vivo. After a range of doses of irradiation, SRC-3-/- mice exhibited lower counts of peripheral blood cells and bone marrow (BM) mononuclear cells and excessive BM depression, which resulted in a significantly higher mortality compared with wildtype mice. Moreover, BM mononuclear cells obtained from SRC-3-/- mice showed a remarkable increase in radiation-induced apoptosis. Collectively, our data demonstrate that SRC-3 plays a role in radiation-induced apoptosis of BM hematopoietic cells. Regulation of SRC-3 might influence the radiosensitivity of hematopoietic cells, which highlights a potential therapeutic target for radiation-induced hematopoietic injury.

Jin, Jie; Wang, Yu; Wang, Jin; Xu, Yang; Chen, Shilei; Wang, Junping; Ran, Xinze; Su, Yongping

2014-01-01

225

Radiation-induced alterations in mitochondria of the rat heart.  

PubMed

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

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

2014-03-01

226

Radiation-induced defects in clay minerals: A review  

NASA Astrophysics Data System (ADS)

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 ? 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.

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

2012-04-01

227

Radiation-induced conductivity control in polyaniline blends/composites  

NASA Astrophysics Data System (ADS)

Polyaniline (PANI) blends with chlorine-containing polymers and copolymers and composites with HCl-releasing compounds were prepared to investigate their radiation response in terms of induced conductivities. Blends of non-conductive PANI with poly(vinyl chloride) (PVC), poly(vinylidene chloride- co-vinyl acetate), [P(VDC- co-VAc)], poly(vinylidene chloride- co-vinyl chloride), [P(VDC- co-VC)] were prepared in the form of as-cast films. A number of blends which are different in composition were exposed to gamma radiation and accelerated electrons to various doses, and the effects of irradiation type and composition of polymers on the conductivity of films were investigated by using conductivity measurements and UV-vis and FT-IR spectroscopy. The results clearly showed that ionizing radiation is an effective tool to induce and control conductivity in the blends of PANI-base with chlorine-carrying polymers as well as its composites prepared from HCl-releasing compounds such as chloral hydrate. The main mechanism behind this radiation-induced conductivity is in situ doping of PANI-base with HCl released from partner polymers and low molecular weight compounds by the effect of radiation.

Güven, Olgun

2007-08-01

228

Investigations of radiation-induced and carrier-enhanced conductivity  

NASA Astrophysics Data System (ADS)

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

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

1985-03-01

229

Radiation-induced sarcomas of the chest wall  

SciTech Connect

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.

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

1986-02-01

230

Modelling radiation-induced bystander effect and cellular communication.  

PubMed

In the last 10 years evidence has accumulated on the so-called radiation-induced 'non-targeted effects' and in particular on bystander effects, consisting of damage induction in non-irradiated cells most likely following the release of soluble factors by the irradiated ones. These phenomena were observed for different biological endpoints, both lethal and non-lethal for the cell. Although the underlying mechanisms are largely unknown, it is now widely recognised that two types of cellular communication (i.e. via gap junctions and/or release of molecular messengers into the extracellular environment) play a pivotal role. Furthermore, the effects can be significantly modulated by parameters such as cell type and cell-cycle stage, cell density, time after irradiation etc. Theoretical models and simulation codes can be of help to improve our knowledge of the mechanisms, as well as to investigate the possible role of these effects in determining deviations from the linear relationship between dose and risk which is generally applied in radiation protection. In this paper three models, including an approach under development at the University of Pavia, will be presented in detail. The focus will be on the various adopted assumptions, together with their implications in terms of non-targeted radiobiological damage and, more generally, low-dose radiation risk. Comparisons with experimental data will also be discussed. PMID:17142819

Ballarini, F; Alloni, D; Facoetti, A; Mairani, A; Nano, R; Ottolenghi, A

2006-01-01

231

Radiation-induced chromosomal instability in human mammary epithelial cells  

NASA Astrophysics Data System (ADS)

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.

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

232

Outcome of Carotid Artery Stenting for Radiation-Induced Stenosis  

SciTech Connect

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.

Dorresteijn, Lucille, E-mail: L.Dorresteijn@mst.n [Department of Neurology, Radboud University Nijmegen Medical Centre, Donders Institute for Brain, Cognition and Behaviour, Nijmegen (Netherlands); Vogels, Oscar [Department of Neurology and Clinical Neurophysiology, St Antonius Hospital, Nieuwegein (Netherlands); Leeuw, Frank-Erik de [Department of Neurology, Radboud University Nijmegen Medical Centre, Donders Institute for Brain, Cognition and Behaviour, Nijmegen (Netherlands); Vos, Jan-Albert [Department of Radiology, St Antonius Hospital, Nieuwegein (Netherlands); Christiaans, Marleen H. [Department of Neurology, Diakonessenhuis, Utrecht (Netherlands); Ackerstaff, Rob [Department of Neurology and Clinical Neurophysiology, St Antonius Hospital, Nieuwegein (Netherlands); Kappelle, Arnoud C. [Department of Neurology, Radboud University Nijmegen Medical Centre, Donders Institute for Brain, Cognition and Behaviour, Nijmegen (Netherlands)

2010-08-01

233

Investigations of radiation-induced and carrier-enhanced conductivity  

NASA Technical Reports Server (NTRS)

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

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

1985-01-01

234

Radiation-induced vascular lesions of the skin: an overview.  

PubMed

Radiation-induced cutaneous vascular neoplasms occur infrequently and comprise benign, so-called atypical vascular lesions (AVL) and angiosarcomas (AS), often being high-grade malignant tumors. Both arise most frequently within previously irradiated skin in breast-conserving-treated mammary cancer patients. Because of the different clinical course and, consequently, different therapeutic approaches, histopathologic distinction of AVL and AS is essential but significant morphologic overlap has been documented. Furthermore, the coexistence of these lesions or progression of AVL into AS has rarely been reported. Whether AVL is a precursor of AS is much debated and unresolved to date. Recent interest has focused on genetic changes and their differences in AS and AVL. MYC amplification and expression of the corresponding protein has been identified in AS in comparison with AVL. Therefore, MYC fluorescent in situ hybridization and anti-MYC immunohistochemical analysis are diagnostically useful in difficult cases. Furthermore, advanced tailored treatment strategies in AS, one of the most aggressive type of sarcoma, rely on identifying genes and proteins involved in malignant angiogenesis. PMID:24113311

Flucke, Uta; Requena, Luis; Mentzel, Thomas

2013-11-01

235

Radiation-Induced Sarcoma of the Breast: A Systematic Review  

PubMed Central

Introduction. Radiation-induced sarcoma (RIS) is a rare, aggressive malignancy. Breast cancer survivors treated with radiotherapy constitute a large fraction of RIS patients. To evaluate evidenced-based practices for RIS treatment, we performed a systematic review of the published English-language literature. Methods. We performed a systematic keyword search of PubMed for original research articles pertaining to RIS of the breast. We classified and evaluated the articles based on hierarchal levels of scientific evidence. Results. We identified 124 original articles available for analysis, which included 1,831 patients. No randomized controlled trials involving RIS patients were found. We present the best available evidence for the etiology, comparative biology to primary sarcoma, prognostic factors, and treatment options for RIS of the breast. Conclusion. Although the evidence to guide clinical practice is limited to single institutional cohort studies, registry studies, case–control studies, and case reports, we applied the available evidence to address clinically relevant questions related to best practice in patient management. Surgery with widely negative margins remains the primary treatment of RIS. Unfortunately, the role of adjuvant and neoadjuvant chemotherapy remains uncertain. This systematic review highlights the need for additional well-designed studies to inform the management of RIS.

Sheth, Grishma R.; Cranmer, Lee D.; Smith, Benjamin D.; Grasso-LeBeau, Lauren

2012-01-01

236

Radiation induced oxidative damage modification by cholesterol in liposomal membrane  

NASA Astrophysics Data System (ADS)

Ionizing radiation induced structural and chemical alterations in egg lecithin liposomal membrane have been studied by measurements of lipid peroxides, conjugated diene and fluorescence polarization. Predominantly unilamellar phospholipid vesicles prepared by sonication procedure were subjected to radiation doses of ?-rays from Co-60 in aerated, buffered aqueous suspensions. The oxidative damage in irradiated lipid molecules of liposomes has been determined spectrophotometrically by diene conjugate formation and thiobarbituric acid reactive (TBAR) method as a function of radiation dose. A correlation was found between the radiation dose applied (0.1-1 kGy) and the consequent lipid oxidation. The damage produced in irradiated liposomal membrane was measured by 1,6-diphenyl-1,3,5-hexatriene (DPH) fluorescence decay and polarization. The observed decrease in DPH fluorescence and increase in polarization was found dependent on the radiation dose suggesting alterations in rigidity or organizational order in phospholipid bilayer after irradiation. Furthermore, irradiated liposome vesicles composed of cholesterol showed marked reduction in observed radiation mediated peroxide formation and significantly affected the DPH fluorescence parameters. The magnitude of these modifying effects were found dependent on the mole fraction of cholesterol. It is concluded that modulation of structural order in unilamellar vesicle membrane by variations in basic molecular components controlled the magnitude of lipid peroxidation and diene conjugate formation. These observations contribute to our understanding of mechanism of radical reaction mediated damage caused by ionizing radiation in phospholipid membrane.

Pandey, B. N.; Mishra, K. P.

1999-05-01

237

Mechanism of Hydrophilicity by Radiation-Induced Surface Activation  

NASA Astrophysics Data System (ADS)

When a metal oxide is irradiated by gamma rays, the irradiated surface becomes hydrophilic. This surface phenomenon is called as radiation-induced surface activation (RISA) hydrophilicity. In order to investigate gamma ray-induced and photoinduced hydrophilicity, the contact angles of water droplets on a titanium dioxide surface were measured in terms of irradiation intensity and time for gamma rays of cobalt-60 and for ultraviolet rays. Reciprocals of the contact angles increased in proportion to the irradiation time before the contact angles reached its super-hydrophilic state. The irradiation time dependency is equal to each other qualitatively. In addition, an effect of ambient gas was investigated. In pure argon gas, the contact angle remains the same against the irradiation time. This clearly indicates that certain humidity is required in ambient gas to take place of RISA hydrophilicity. A single crystal titanium dioxide (100) surface was analyzed by X-ray photoelectron spectrometry (XPS). After irradiation with gamma rays, a peak was found in the O1s spectrum, which indicates the adsorption of dissociative water to a surface 5-fold coordinate titanium site, and the formation of a surface hydroxyl group. We conclude that the RISA hydrophilicity is caused by chemisorption of the hydroxyl group on the surface.

Honjo, Yoshio; Furuya, Masahiro; Takamasa, Tomoji; Okamoto, Koji

238

Mechanisms of radiation-induced neoplastic cell transformation  

SciTech Connect

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.

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

1984-04-01

239

Early corticosteroid administration in experimental radiation-induced heart disease  

SciTech Connect

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

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

1980-02-01

240

Interleukin-32 Positively Regulates Radiation-Induced Vascular Inflammation  

SciTech Connect

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.

Kobayashi, Hanako; Yazlovitskaya, Eugenia M. [Department of Radiation Oncology, Vanderbilt-Ingram Cancer Center, Vanderbilt University Medical Center, Nashville, TN (United States); Lin, P. Charles [Department of Radiation Oncology, Vanderbilt-Ingram Cancer Center, Vanderbilt University Medical Center, Nashville, TN (United States); Department of Cancer Biology, Vanderbilt-Ingram Cancer Center, Vanderbilt University Medical Center, Nashville, TN (United States); Department of Cell and Development Biology, Vanderbilt-Ingram Cancer Center, Vanderbilt University Medical Center, Nashville, TN (United States)], E-mail: Charles.lin@vanderbilt.edu

2009-08-01

241

Does oxygen enhance the radiation-induced inactivation of penicillinase  

SciTech Connect

The radiation-induced inactivation of penicillinase (..beta..-lactamase, EC 3.5.2.6) in dilute aqueous solutions buffered with phosphate was studied by examining enzyme radiosensitivity in the presence of various gases (He, O/sub 2/, H/sub 2/, N/sub 2/O and N/sub 2/O + O/sub 2/). The introduction of either N/sub 2/O or O/sub 2/ was found to reduce the radiodamage. On the other hand, H/sub 2/ or N/sub 2/O + O/sub 2/ gas mixture enhanced the radiosensitivity. In the presence of formate and oxygen no enzyme inactivation was detected. The results indicated that the specific damaging efficiency of H atoms is more than twofold higher than that of OH radicals; therefore, in 50 mM phosphate buffer, where more than half the free radicals are H atoms, the H radicals are responsible for the majority of the damage. The superoxide radicals appeared to be completely inactive and did not contribute to enzyme inactivation. Oxygen affected the radiosensitivity in two ways: (1) it protected by converting e/sub aq//sup -/ and H into harmless O/sub 2/-radicals; and (2) it increased inactivation by enhancing the damage brought about by OH radicals (OER = 2.6). In oxygenated buffer the protection effect of oxygen exceeded that of sensitization, thus giving rise to a moderate overall protection effect.

Samuni, A.; Kalkstein, A.; Czapski, G.

1980-04-01

242

Radiation-Induced Bystander Response: Mechanism and Clinical Implications  

PubMed Central

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.

Suzuki, Keiji; Yamashita, Shunichi

2014-01-01

243

Adaptive radiation-induced epigenetic alterations mitigated by antioxidants  

PubMed Central

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.

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

2013-01-01

244

Molecular Mechanisms and Treatment of Radiation-Induced Lung Fibrosis  

PubMed Central

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.

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

2013-01-01

245

Radiation-induced removal of sulphadiazine antibiotics from wastewater.  

PubMed

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

Liu, Yuankun; Hu, Jun; Wang, Jianlong

2014-08-01

246

Neurosurgical management of birth injuries of the brachial plexus.  

PubMed

While most newborns with birth injury of the brachial plexus make a full spontaneous recovery, the minority who do not can expect lifelong disability from weakness, disturbed patterns of muscle activity, contracture, and deformity. Those children who are destined to a poor recovery can be identified in early infancy. Early reconstruction of the brachial plexus carries low morbidity and has been shown by many to support useful shoulder and elbow function. Patients who are referred later in childhood may still benefit from plexus exploration, but how to best use clinical and electrophysiologic data to plan a surgical intervention that will improve on the natural history remains to be elucidated for this group. PMID:1821731

Piatt, J H

1991-01-01

247

Acromioclavicular joint dislocation with associated brachial plexus injury.  

PubMed

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

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

2014-01-01

248

Scapular deformity in obstetric brachial plexus palsy: a new finding  

Microsoft Academic Search

While most obstetric brachial plexus palsy patients recover arm and hand function, the residual nerve weakness leads to muscle\\u000a imbalances about the shoulder which may cause bony deformities. In this paper we describe abnormalities in the developing\\u000a scapula and the glenohumeral joint. We introduce a classification for the deformity which we term Scapular Hypoplasia, Elevation\\u000a and Rotation. Multiple anatomic parameters

Rahul K. Nath; Melia Paizi

2007-01-01

249

Upright MRI of glenohumeral dysplasia following obstetric brachial plexus injury  

Microsoft Academic Search

The purpose of this study was to evaluate the role of upright magnetic resonance imaging (MRI) shoulder scanning in the diagnosis of glenohumeral deformity following obstetric brachial plexus injury (OBPI). Eighty-nine children (ages 0.4 to 17.9 years) with OBPI who have medial rotation contracture and reduced passive and active lateral rotation of the shoulder were evaluated via upright MRI of

Rahul K. Nath; Melia Paizi; Sonya E. Melcher; Kim L. Farina

2007-01-01

250

Different Ankle Brachial Index Levels in Asymptomatic Hemodialysis Patients  

Microsoft Academic Search

Resting ankle brachial systolic pressure index (ABI) level of 0.90 is 95% sensitive in detecting angiogram-positive peripheral arterial disease (PAD) and that falsely elevated pressures or incompressible arteries at the ankle level and ABI > 1.30 is caused by mediosclerosis. We evaluated 94 hemodialysis (HD) patients for the presence of PAD and mediosclerosis using ABI measurement, and the presence of

Saso Gelev; Goce Spasovski; Sonja Dzikova; Slavcho Tosev; Marjan Bosevski; Gjulsen Selim; Pavlina Dzekova; Vili Amitov; Aleksandar Sikole

2008-01-01

251

Statin therapy improves brachial artery endothelial function in nephrotic syndrome  

Microsoft Academic Search

Statin therapy improves brachial artery endothelial function in nephrotic syndrome.Background:Patients with nephrotic syndrome have impaired endothelial function probably related to dyslipidemia. This study evaluated the effects of statin therapy on dyslipidemia and endothelial function in patients with nephrotic syndrome.Methods:A sequential, open-label study of the effects of statins on endothelial dysfunction in 10 nephrotic patients treated with an angiotensin-converting enzyme (ACE)

Gursharan K Dogra; Gerald F Watts; Susan Herrmann; Mark A B Thomas; Ashley B Irish

2002-01-01

252

[Total spinal paralysis as complication of brachial plexus block].  

PubMed

Local anesthesia of the brachial plexus by interscalenic approach was a cause of total spinal blockade due to the administration of a local anesthetic into subarachnoid space. To prevent this it is necessary to administer a test dose of a local anesthetic with pre-aspiration of the liquor with a syringe. Intensive care procedures should be aimed at maintenance of adequate hemodynamics and gas exchange and to liquidation of circulating blood volume deficiency. PMID:7943912

Strelets, B M; Tsvetkov, V A; Evtiukhov, A N

1993-01-01

253

Brachial and lumbar plexitis as a reaction to heroin.  

PubMed

A case is described of a young man who presented with acute pulmonary edema and flaccid paralysis of the right upper and lower extremity, following his first injection of heroin and was found in a comatose state. Needle electromyographic findings were compatible with a severe lesion of the right brachial plexus and a moderate lesion of the right lumbar plexus. An allergic or a hypersensitivity reaction might have been the possible cause. PMID:3234243

Stamboulis, E; Psimaras, A; Malliara-Loulakaki, S

1988-12-01

254

Autophagy promotes radiation-induced senescence but inhibits bystander effects in human breast cancer cells.  

PubMed

Ionizing radiation induces cellular senescence to suppress cancer cell proliferation. However, it also induces deleterious bystander effects in the unirradiated neighboring cells through the release of senescence-associated secretory phenotypes (SASPs) that promote tumor progression. Although autophagy has been reported to promote senescence, its role is still unclear. We previously showed that radiation induces senescence in PTTG1-depleted cancer cells. In this study, we found that autophagy was required for the radiation-induced senescence in PTTG1-depleted breast cancer cells. Inhibition of autophagy caused the cells to switch from radiation-induced senescence to apoptosis. Senescent cancer cells exerted bystander effects by promoting the invasion and migration of unirradiated cells through the release of CSF2 and the subsequently activation of the JAK2-STAT3 and AKT pathways. However, the radiation-induced bystander effects were correlated with the inhibition of endogenous autophagy in bystander cells, which also resulted from the activation of the CSF2-JAK2 pathway. The induction of autophagy by rapamycin reduced the radiation-induced bystander effects. This study reveals, for the first time, the dual role of autophagy in radiation-induced senescence and bystander effects. PMID:24813621

Huang, Yao-Huei; Yang, Pei-Ming; Chuah, Qiu-Yu; Lee, Yi-Jang; Hsieh, Yi-Fen; Peng, Chih-Wen; Chiu, Shu-Jun

2014-07-01

255

Scapular deformity in obstetric brachial plexus palsy: a new finding.  

PubMed

While most obstetric brachial plexus palsy patients recover arm and hand function, the residual nerve weakness leads to muscle imbalances about the shoulder which may cause bony deformities. In this paper we describe abnormalities in the developing scapula and the glenohumeral joint. We introduce a classification for the deformity which we term Scapular Hypoplasia, Elevation and Rotation. Multiple anatomic parameters were measured in bilateral CT images and three-dimensional CT reconstruction of the shoulder girdle of 30 obstetric brachial plexus palsy patients (age range 10 months-10.6 years). The affected scapulae were found to be hypoplastic by an average of 14% while the ratio of the height to the width of the body of scapula (excluding acromion) were not significantly changed, the acromion was significantly elongated by an average of 19%. These parameters as well as subluxation of the humeral head (average 14%) and downward rotation in the scapular plane were found to correlate with the area of scapula visible over the clavicle. This finding provides a classification tool for diagnosis and objective evaluation of the bony deformity and its severity in obstetric brachial plexus palsy patients. PMID:17262175

Nath, Rahul K; Paizi, Melia

2007-03-01

256

Conception of the cervico-brachial protector for motorcycle drivers.  

PubMed

The increasing popularity of motorcycles increases the role of motorcycle accidents as a main cause of brachial plexus injuries. In view of the high social cost of treatment of the victims it seemed desirable to devise some kind of protective clothing for motorcyclists. The protective clothing devised by teams from Department of Neurosurgery, TRICOTEXTIL--and Aeronautics and Applied Mechanics Institute, consists of the following parts: cervical collar--acting against force causing lateral bending and extension of cervical spine, shock-absorptive shoulder pads--acting against the impact energy partially absorbing it and partially transmitting to the dorsal stiff bar, dorsal stiff bar and sacroiliac belt--partially immobilizes the thoracic and lumbar spine, acts against its compression, transmits the impact energy to the iliac crests and hips. The expected biomechanical effects of the cervico-brachial protector are as follows: In brachial region it should diminish the impact energy by its partial absorption and partial transmission along dorsal stiff bar to sacroiliac belt. It should act against excessive cervical spine motion--mainly against lateral bending and extension. It should act against excessive depression of the shoulder. The protective system built in the jacket should co-operate with the helmet of motorcycle driver. It should be comfortable for the driver and conform to security standards. Prototype of the protector underwent kinetic sledge tests in Industrial Motorization Institute (PIMOT), Warsaw, with the use of Hybrid Dummy II. PMID:11452862

Radek, A; Zapa?owicz, K; Nawrocki, A; Demus, J; Maklewska, E; Matyjewski, M

2000-01-01

257

Neonatal brachial plexus palsy-Management and prognostic factors.  

PubMed

Successful treatment of patients with neonatal brachial plexus palsy (NBPP) begins with a thorough understanding of the anatomy of the brachial plexus and of the pathophysiology of nerve injury via which the brachial plexus nerves stretched in the perinatal period manifest as a weak or paralyzed upper extremity in the newborn. NBPP can be classified by systems that can guide the prognosis and the management as these systems are based on the extent and severity of nerve injury, anatomy of nerve injury, and clinical presentation. Serial physical examinations, supplemented by a thorough maternal and perinatal history, are critical to the formulation of the treatment plan that relies upon occupational/physical therapy and rehabilitation management but may include nerve reconstruction and secondary musculoskeletal surgeries. Adjunctive imaging and electrodiagnostic studies provide additional information to guide prognosis and treatment. As research improves not only the technical aspects of NBPP treatment but also the ability to assess the activity and participation as well as body structure and function of NBPP patients, the functional outcomes for affected infants have an overall optimistic prognosis, with the majority recovering adequate functional use of the affected arm. Of importance are (i) early referral to interdisciplinary specialty clinics that can provide up-to-date advances in clinical care and (ii) increasing research/awareness of the psychosocial and patient-reported quality-of-life issues that surround the chronic disablement of NBPP. PMID:24863029

Yang, Lynda J-S

2014-06-01

258

A Two Trunked Brachial Plexus: A Case Report  

PubMed Central

The brachial plexus is a major and a complicated plexus at the root of the neck. It is formed by the ventral primary rami of the C5, C6, C7, C8 and the T1 spinal nerves. During the routine under graduate dissection of the right upper limb of an adult female cadaver, a variant pattern of a two trunked brachial plexus was encountered. The upper trunk was formed by the fusion of the C5 and the C6 roots. The C7 root, instead of continuing as the middle trunk, joined with the roots of C8 and T1 to form the lower trunk. On the left side, the usual pattern of the brachial plexus was seen. The knowledge on such variations are of interest to anatomists, clinicians, anesthesiologists and especially, to surgeons. These are of immense importance during surgical explorations of the axilla and the arm region and also during nerve blocks. It also helps the clinicians in getting a proper understanding of some previously unexplained clinical symptoms. Further, the ontogeny and the phylogeny of this entity have been discussed in detail.

Singla, Rajan Kumar; Sharma, Ravi Kant; Shree, Bhagya

2013-01-01

259

Correspondence in relation to the case report "Capnography as an aid in localizing the phrenic nerve in brachial plexus surgery. Technical note." published in May issue of Journal of Brachial Plexus and Peripheral Nerve Injury  

PubMed Central

Comment on 'Capnography as an aid in localizing the phrenic nerve in brachial plexus surgery. Technical note' Bhagat H, Agarwal A, Sharma MS Journal of Brachial Plexus and Peripheral Nerve Injury 2008, 3:14 (22 May 2008)

2008-01-01

260

Radiation-Induced Phase Transformations in Ilmenite-Group Minerals  

SciTech Connect

Transmission electron microscopy (TEM) is a powerful tool for characterizing and understanding radiation-induced structural changes in materials. We have irradiated single crystals of ilmenite (FeTiO{sub 3}) and geikielite (MgTiO{sub 3}) using ions and electrons to better understand the response of complex oxides to radiation. Ion irradiation experiments of bulk single crystals at 100 K show that ilmenite amorphized at doses of less than 1x10(exp15) Ar(2+)/sq cm and at a damage level in the peak damage region of 1 displacement per atom (dpa). Transmission electron microscopy and electron diffraction of a cross-sectioned portion of this crystal confirmed the formation of a 150 am thick amorphous layer. Geikielite proved to be more radiation resistant, requiring a flux of 2x10(exp 15) Xe(2+)/sq cm to induce amorphization at 100 K. This material did not amorphize at 470 K, despite a dose of 2.5 x10(exp 16) Xe(2+)/sq cm and a damage level as high as 25 dpa. Low temperature irradiations of electron- transparent crystals with 1 MeV Kr(+) also show that ilmenite amorphized after a damage level of 2.25 dpa at 175 K.Similar experiments on geikielite show that the microstructure is partially amorphous and partially crystalline after 10 dpa at 150 K. Concurrent ion and electron irradiation of both materials with 1 MeV Kr(+) and 0.9 MeV electrons produced dislocation loops in both materials, but no amorphous regions were formed. Differences in the radiation response of these isostructural oxides suggests that in systems with Mg-Fe solid solution, the Mg-rich compositions may be more resistant to structural changes.

Mitchell, J. N.

1997-12-31

261

Dosimetric Analysis of Radiation-induced Gastric Bleeding  

SciTech Connect

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.

Feng, Mary, E-mail: maryfeng@umich.edu [Department of Radiation Oncology, University of Michigan School of Medicine, Ann Arbor, Michigan (United States)] [Department of Radiation Oncology, University of Michigan School of Medicine, Ann Arbor, Michigan (United States); Normolle, Daniel [Department of Biostatistics, University of Pittsburgh, Pittsburgh, Pennsylvania (United States)] [Department of Biostatistics, University of Pittsburgh, Pittsburgh, Pennsylvania (United States); Pan, Charlie C. [Department of Radiation Oncology, University of Michigan School of Medicine, Ann Arbor, Michigan (United States)] [Department of Radiation Oncology, University of Michigan School of Medicine, Ann Arbor, Michigan (United States); Dawson, Laura A. [Department of Radiation Oncology, Princess Margaret Hospital, University of Toronto, Toronto, Ontario (Canada)] [Department of Radiation Oncology, Princess Margaret Hospital, University of Toronto, Toronto, Ontario (Canada); Amarnath, Sudha [Department of Radiation Oncology, University of Michigan School of Medicine, Ann Arbor, Michigan (United States)] [Department of Radiation Oncology, University of Michigan School of Medicine, Ann Arbor, Michigan (United States); Ensminger, William D. [Department of Internal Medicine, Division of Hematology Oncology, University of Michigan School of Medicine, Ann Arbor, Michigan (United States)] [Department of Internal Medicine, Division of Hematology Oncology, University of Michigan School of Medicine, Ann Arbor, Michigan (United States); Lawrence, Theodore S.; Ten Haken, Randall K. [Department of Radiation Oncology, University of Michigan School of Medicine, Ann Arbor, Michigan (United States)] [Department of Radiation Oncology, University of Michigan School of Medicine, Ann Arbor, Michigan (United States)

2012-09-01

262

?-Tocopherol succinate protects mice against radiation-induced gastrointestinal injury.  

PubMed

The purpose of this study was to elucidate the role of ?-tocopherol succinate (?-TS) in protecting mice from gastrointestinal syndrome induced by total-body irradiation. CD2F1 mice were injected subcutaneously with 400 mg/kg of ?-TS and exposed to different doses of (60)Co ? radiation, and 30-day survival was monitored. Jejunum sections were analyzed for crypts and villi, PUMA (p53 upregulated modulator of apoptosis), and apoptosis (terminal deoxynucleotidyl transferase dUTP nick end labeling - TUNEL). The crypt regeneration in irradiated mice was evaluated by 5-bromo-2-deoxyuridine (BrdU). Bacterial translocation from gut to heart, spleen and liver in ?-TS-treated and irradiated mice was evaluated by bacterial culture on sheep blood agar, colistin-nalidixic acid, and xylose-lysine-desoxycholate medium. Our results demonstrate that ?-TS enhanced survival in a significant number of mice irradiated with 9.5, 10, 11 and 11.5 Gy (60)Co ? radiation when administered 24 h before radiation exposure. ?-TS also protected the intestinal tissue of irradiated mice in terms of crypt and villus number, villus length and mitotic figures. TS treatment decreased the number of TUNEL- and PUMA-positive cells and increased the number of BrdU-positive cells in jejunum compared to vehicle-treated mice. Further, ?-TS inhibited gut bacterial translocation to the heart, spleen and liver in irradiated mice. Our data suggest that ?-TS protects mice from radiation-induced gastrointestinal damage by inhibiting apoptosis, promoting regeneration of crypt cells, and inhibiting translocation of gut bacteria. PMID:22013885

Singh, Pankaj K; Wise, Stephen Y; Ducey, Elizabeth J; Fatanmi, Oluseyi O; Elliott, Thomas B; Singh, Vijay K

2012-02-01

263

Radiation-induced grafting of acrylic acid onto polyethylene filaments  

NASA Astrophysics Data System (ADS)

Radiation-induced grafting of acrylic acid onto high density polyethylene (PE) filaments was carried out in order to raise softening temperature and impart flame retardance and hydrophilic properties. Mutual ?-irradiation method was employed for the grafting in a mixture of acrylic acid (AA), ethylene dichloride and water containing a small amount of ferrous ammonium sulfate. The rate of grafting was very low at room temperature. On the other hand, large percent grafts were obtained when the grafting was performed at an elevated temperature. Activation energy for the initial rate of grafting was found to be 17 {kcal}/{mol} between 20 and 60°C and 10 {kcal}/{mol} between 60 and 80°C. Original PE filament begins to shrink at 70°C, show maximum shrinkage of 50% at 130°C and then breaks off at 136°C. When a 34% AA graft is converted to metallic salt such as sodium and calcium, the graft filament retains its filament form even above 300°C and gives maximum shrinkage of 15%. Burning tests by a wire-netting basket method indicate that graft filaments and its metallic salts do not form melting drops upon burning and are self-extinguishing. Original PE filament shows no moisture absorption, however, that of AA-grafted PE increases with increasing graft percent. The sodium salt of 15% graft shows the same level of moisture regain as cotton. The AA-grafted PE filament and its metallic salts can be dyed with cationic dyes even at 1% graft. Tensile properties of PE filament is impaired neither by grafting nor by conversion to metallic salts.

Kaji, K.; Okada, T.; Sakurada, I.

264

Radiation-Induced Dimensional Changes of AM-350 Stainless Steel (LWBR Development Program).  

National Technical Information Service (NTIS)

AM-350 stainless steel, which is used for fuel rod support grids in the Light Water Breeder Reactor, experiences radiation-induced dimensional changes during in-reactor service. Dimensional changes (strain) were measured periodically for two sets of test ...

B. C. Smith B. Z. Hyatt

1982-01-01

265

Use of Photostimulated Luminescence for Studying the Characteristics of Radiation-Induced Electron Centers.  

National Technical Information Service (NTIS)

The kinetics of recombination processes in a solid body depends in great measure on the probability of repeated localizations (RL) of the charge carriers in pre-radiation and radiation induced microdefects. Repeated localizations can determine in a broad ...

B. I. Rogalev, I. A. Parfianovich, P. N. Yarovoii, V. G. Krongauz

1973-01-01

266

Role of Neurotensin in Radiation-Induced Hypothermia in Rats. (Reannouncement with New Availability Information).  

National Technical Information Service (NTIS)

The role of neurotensin in radiation induced hypothermia was examined. Intracerebroventricular (ICV) administration of neurotensin produced dose-dependent hypothermia. Histamine appears to mediate neurotensin-induced hypothermia because the mast cell stab...

S. B. Kandasamy W. A. Hunt A. H. Harris

1991-01-01

267

Mechanisms of Radiation-Induced Bone Loss and Effect on Prostate Cancer Bone Metastases.  

National Technical Information Service (NTIS)

Patients with tumors in the pelvic region frequently receive radiation therapy, and as a result, bystander bone may experience adverse effects. Earlier reports demonstrated that radiation-induced bone loss occurs via increased osteoclast activation in a m...

H. S. Kim

2012-01-01

268

Mechanisms of Radiation-Induced Bone Loss and Effects on Prostate Cancer Bone Metastases.  

National Technical Information Service (NTIS)

Patients with prostate cancer frequently receive radiation therapy. Although radiation therapy is effective for the treatment of primary tumors, bystander bone absorbs approximately half of the radiation dose and thus may cause adverse radiation-induced e...

L. E. Wright

2013-01-01

269

Effects of Radiation-Induced Segregation and Preferential Sputtering on the Sputtering Rate of Alloys.  

National Technical Information Service (NTIS)

Changes in the surface composition and in the sputtering rate of binary alloys were calculated using a kinetic model that includes the effects of radiation-induced segregation and preferential sputtering. Numerical solutions were obtained for two dilute N...

N. Q. Lam G. K. Leaf H. Wiedersich

1979-01-01

270

Renal and Adrenal Factors in Radiation-Induced Hypertension and Nephrosclerosis.  

National Technical Information Service (NTIS)

Experiments were conducted in order to investigate the effects of adrenalectomy on the incidence, severity, and rate of progression of radiation-induced hypertension and nephrosclerosis in male rats. Adrenalectomized and non-adrenalectomized rats received...

A. G. Lurie

1973-01-01

271

Time dependent annealing of radiation - induced leakage currents in MOS devices  

SciTech Connect

Results are presented showing the radiation response of several unhardened commercial 1.25-{mu}m bulk CMOS processes using LOCOS isolation technology. In all cases studied radiation-induced failure is caused by effects in the field oxide, and the radiation-induced {delta}V{sub T} in the channel region is usually small at the failure dose. Time dependent leakage current data for the field oxides are presented and discussed.

Terrell, J.M. (Booz Allen and Hamilton, Inc. Bethesda, MD (US)); Olkham, T.R.; Lelis, A.J.; Benedetto, J.M. (Harry Diamond Labs., Adelphi, MD (US))

1989-12-01

272

Effects of Berberine Against Radiation-Induced Intestinal Injury in Mice  

Microsoft Academic Search

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,

Guang-Hui Li; Ya-Ping Zhang; Jin-liang Tang; Zheng-Tang Chen; Yi-De Hu; Hong Wei; De-Zhi Li; Ping Hao; Dong-Lin Wang

2010-01-01

273

Temperature and Doping Level Dependence of Delayed Radiation Induced Conductivity in Chromium Polyacrylate  

Microsoft Academic Search

The radiation induced conductivity of post-irradiated chromium polyacrylate (CrPA) is investigated as a function of exposure rate, temperature, doping level (concentration) and field strength. The samples are irradiated with 5.5 MeV 241AM, alpha-source. The exposure rate is varied from 5.96×108 particles\\/cm2 to 3.58×109 particles\\/cm2. It is noted that the radiation induced conductivity in this material increases exponentially, passes through a

A. Rauf; S. U. Rehman; Farid A. Khwaja

1995-01-01

274

Radiation-induced adult medulloblastoma: a two-case report and review of the literature  

Microsoft Academic Search

Radiation-induced medulloblastoma is an exceedingly rare phenomenon for which treatment standards have not been established.\\u000a The literature suggests that these tumors are high grade with aggressive behavior. We report two cases of radiation-induced\\u000a medulloblastoma which have been treated with full dose re-irradiation with curative intent. In both cases, treatment toxicity\\u000a and tumor progression proved to be insurmountable obstacles. Further reports

Michael D. Chan; Albert Attia; Stephen B. Tatter; Glenn Lesser; Michael E. Zapadka; Ryan T. Mott; Annette Carter; Kevin P. McMullen; Edward G. Shaw; Thomas E. Ellis

2011-01-01

275

Self-mutilation in young children following brachial plexus birth injury  

Microsoft Academic Search

Brachial plexus injury in adults commonly produces persistent pain. Pediatric textbooks and case series suggest that perinatal brachial plexus injury is very rarely associated with pain, though this is difficult to determine in preverbal infants. Some of these young children self-mutilate the affected extremity, which may or may not reflect pain. This study was designed to characterize the clinical presentation

Mary Ellen McCann; Peter Waters; Liliana C Goumnerova; Charles Berde

2004-01-01

276

Lipoma compressing the brachial plexus in a patient with sarcoidosis: case report.  

PubMed

Lipomas associated with distal peripheral nerves are well recognized; however, those impinging on the brachial plexus are rare. We document a unique case of a sarcoidosis patient with an extraneural lipoma compressing the brachial plexus, and present a review of the current literature. PMID:21501063

Guha, Daipayan; Kiehl, Tim-Rasmus; Guha, Abhijit

2011-08-01

277

Pleural effusion and atelectasis during continuous interscalene brachial plexus block -A case report-  

PubMed Central

An interscalene brachial plexus block is an effective means of providing anesthesia-analgesia for shoulder surgery. However, it has a multitude of potential side effects such as phrenic nerve block. We report a case of a patient who developed atelectasis of the lung, and pleural effusion manifested as chest discomfort during a continuous interscalene brachial plexus block for postoperative analgesia.

Yang, Chun Woo; Cho, Choon Kyu; Kwon, Hee Uk; Kang, Po Soon; Lim, Young Su; Oh, Jin Young; Yi, Jin Woong

2010-01-01

278

Carotid Pressure Is a Better Predictor of Coronary Artery Disease Severity Than Brachial Pressure  

Microsoft Academic Search

The mechanisms relating pulse pressure to cardiovascular outcome may include surrogacy for coronary disease severity. Although pulse pressure is typically measured at the brachial artery, central pulse pressure and its principal determinant, large-artery stiffness, may relate more closely to disease severity. This study aimed to determine the relationships between large-artery stiffness and carotid and brachial blood pressures and coronary artery

Tamara K. Waddell; Anthony M. Dart; Tanya L. Medley; James D. Cameron; Bronwyn A. Kingwell

279

3T MR tomography of the brachial plexus: structural and microstructural evaluation.  

PubMed

Magnetic resonance (MR) neurography comprises an evolving group of techniques with the potential to allow optimal noninvasive evaluation of many abnormalities of the brachial plexus. MR neurography is clinically useful in the evaluation of suspected brachial plexus traumatic injuries, intrinsic and extrinsic tumors, and post-radiogenic inflammation, and can be particularly beneficial in pediatric patients with obstetric trauma to the brachial plexus. The most common MR neurographic techniques for displaying the brachial plexus can be divided into two categories: structural MR neurography; and microstructural MR neurography. Structural MR neurography uses mainly the STIR sequence to image the nerves of the brachial plexus, can be performed in 2D or 3D mode, and the 2D sequence can be repeated in different planes. Microstructural MR neurography depends on the diffusion tensor imaging that provides quantitative information about the degree and direction of water diffusion within the nerves of the brachial plexus, as well as on tractography to visualize the white matter tracts and to characterize their integrity. The successful evaluation of the brachial plexus requires the implementation of appropriate techniques and familiarity with the pathologies that might involve the brachial plexus. PMID:21763092

Mallouhi, Ammar; Marik, Wolfgang; Prayer, Daniela; Kainberger, Franz; Bodner, Gerd; Kasprian, Gregor

2012-09-01

280

Ultrasound-Guided Brachial and Basilic Vein Cannulation in Emergency Department Patients With Difficult Intravenous Access  

Microsoft Academic Search

Study objective: Emergency department patients who require intravenous access but lack peripheral intravenous sites frequently require central line placement. Blind percutaneous brachial vein cannulation has been proposed as an alternative in these patients but is associated with high failure and complication rates. We evaluated an ultrasound-guided approach to percutaneous deep brachial vein or basilic vein cannulation in ED patients with

Linda E Keyes; Bradley W Frazee; Eric R Snoey; Barry C Simon; David Christy

1999-01-01

281

Disuse osteoporosis as evidence of brachial plexus palsy due to intrauterine fetal maladaptation  

Microsoft Academic Search

We report what may be overlooked evidence of the effects of intrauterine maladaptation as a cause of brachial plexus palsy. A case of total brachial plexus palsy in the posterior arm associated with Horner’s syndrome and severe demineralization of the bones of the affected arm is analyzed. In this litigated case, a report of marked demineralization of the bones of

Raymond J. Jennett; Theodore J. Tarby

2001-01-01

282

Variability of ankle and brachial systolic pressures in the measurement of atherosclerotic peripheral arterial disease  

Microsoft Academic Search

The aim of this study was to determine the variability of measurements of ankle and brachial systolic pressures and ankle brachial ratios in order to assess their suitability for use in epidemiological studies of arterial disease in the lower limbs. Thirty-six subjects had repeat measurements taken by four observers on two separate days using a Doppler probe and random zero

F G Fowkes; E Housley; C C Macintyre; R J Prescott; C V Ruckley

1988-01-01

283

Radiation-induced osteosarcomas in the pediatric population  

SciTech Connect

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.

Koshy, Matthew [Department of Radiology, Division of Radiation Oncology, Baylor College of Medicine, Methodist Hospital, and Texas Children's Hospital, Houston, TX (United States); Paulino, Arnold C. [Department of Radiology, Division of Radiation Oncology, Baylor College of Medicine, Methodist Hospital, and Texas Children's Hospital, Houston, TX (United States)]. E-mail: apaulino@tmh.tmc.edu; Mai, Wei Y. [Department of Radiology, Division of Radiation Oncology, Baylor College of Medicine, Methodist Hospital, and Texas Children's Hospital, Houston, TX (United States); Teh, Bin S. [Department of Radiology, Division of Radiation Oncology, Baylor College of Medicine, Methodist Hospital, and Texas Children's Hospital, Houston, TX (United States)

2005-11-15

284

Radiation-Induced Topological Disorder in Irradiated Network Structures  

SciTech Connect

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

Hobbs, Linn W.

2002-12-21

285

Comparison of Ankle-Brachial Index and Brachial-Ankle Pulse Wave Velocity between Patients with Chronic Kidney Disease and Hemodialysis  

Microsoft Academic Search

Background\\/Aims: Patients with chronic renal failure are highly predisposed to atherosclerosis. However, there is limited data about the direct comparison of atherosclerosis between patients with chronic kidney disease (CKD) and hemodialysis. The aim of this study was to compare ankle-brachial index (ABI) and brachial-ankle pulse wave velocity (baPWV) between patients with CKD and hemodialysis and thus examined the status of

Szu-Chia Chen; Jer-Ming Chang; Shang-Jyh Hwang; Jui-Hsin Chen; Feng-Hsien Lin; Ho-Ming Su; Hung-Chun Chen

2009-01-01

286

Prognostic Significance of Ankle-Brachial Index, Brachial-Ankle Pulse Wave Velocity, Flow-Mediated Dilation, and Nitroglycerin-Mediated Dilation in End-Stage Renal Disease  

Microsoft Academic Search

Background: Identifying patients at high risk of cardiovascular disease is important in managing patients undergoing hemodialysis. Methods: We evaluated a series of prognostic values: flow-mediated dilation (FMD) and nitrogen-mediated dilation (NMD), an index of endothelium-dependent and endothelium-independent function, respectively, ankle-brachial index (ABI), and brachial-ankle pulse wave velocity (baPWV) in patients undergoing chronic hemodialysis. Results: A cohort of 199 patients was

Satoshi Morimoto; Takatomi Yurugi; Yasuko Aota; Takao Sakuma; Fusakazu Jo; Mitsushige Nishikawa; Toshiji Iwasaka; Kei Maki

2009-01-01

287

Influence of Different Measurement Time Points on Brachial-Ankle Pulse Wave Velocity and Ankle-Brachial Index in Hemodialysis Patients  

Microsoft Academic Search

In order to ensure that they are reliable markers of atherosclerosis and suitable for repetitive follow-up of disease progression and management responses in hemodialysis (HD) patients, brachial-ankle pulse wave velocity (baPWV) and ankle-brachial index (ABI) should be tested to see whether they change with different measurement time points. The aim of this study was to assess whether baPWV and ABI

Ho-Ming Su; Jer-Ming Chang; Feng-Hsien Lin; Szu-Chia Chen; Wen-Chol Voon; Kai-Hung Cheng; Chuan-Sheng Wang; Tsung-Hsien Lin; Wen-Ter Lai; Sheng-Hsiung Sheu

2007-01-01

288

Effects of Heart Rate on Brachial-Ankle Pulse Wave Velocity and Ankle-Brachial Pressure Index in Patients Without Significant Organic Heart Disease  

Microsoft Academic Search

This study evaluated the effects of heart rate (HR) on brachial-ankle pulse wave velocity (baPWV) and ankle-brachial pressure index (ABI). Thirty-two patients without significant organic heart disease underwent elective cardiac catheterization or electrophysiologic study, and were then enrolled in right atrial pacing (RAP; 11 men, 9 women; aged 48 ∓15 years) or right ventricular pacing (RVP; 6 men, 6 women,

Ho-Ming Su; Kun-Tai Lee; Chih-Sheng Chu; Ming-Yi Lee; Tsung-Hsien Lin; Wen-Chol Voon; Sheng-Hsiung Sheu; Wen-Ter Lai

2007-01-01

289

Finger movement at birth in brachial plexus birth palsy  

PubMed Central

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

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

2013-01-01

290

Ultrasound guidance improves success rate of axillary brachial plexus block  

Microsoft Academic Search

Purpose  The purpose of this study is to determine if real time ultrasound guidance improves the success rate of axillary brachial\\u000a plexus blockade.\\u000a \\u000a \\u000a \\u000a Methods  Patients undergoing elective hand surgery were randomly assigned to one of three groups. Axillary blocks were performed using\\u000a three motor response endpoints in the nerve stimulator (NS) Group, real-time ultrasound guidance in the ultrasound (US) Group\\u000a and combined

Vincent W. S. Chan; Anahi Perlas; Colin J. L. McCartney; Richard Brull; Daquan Xu; Sherif Abbas

2007-01-01

291

Image-based modeling of radiation-induced foci  

NASA Astrophysics Data System (ADS)

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 ?H2AX 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 ?H2AX 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.

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

292

Synchrotron-Radiation Induced X-Ray Emission (SRIXE)  

SciTech Connect

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.

Jones, Keith W.

1999-09-01

293

Characteristics of radiation induced light in optical fibres for portal imaging application  

NASA Astrophysics Data System (ADS)

The purpose of this paper is to characterize the radiation induced light in optical fibres to optimise the design of a new Cherenkov detector for portal imaging application in radiation therapy. Experiments were performed using a single optical fibre to evaluate the angle dependence, spectrum and temporal properties of the radiation induced light in the optical fibre in comparison with that of Cherenkov radiation. A theoretical model was also developed to compare with experiments. It has been found that radiation-induced light output from the optical fibre under megavoltage (MV) x-ray irradiation is significantly (about 45 times) higher than that under 100 kVp x-ray irradiation for the same dose rate at the fibre. The angular-dependence, spectrum and temporal properties of the radiation induced light in the optical fibre under MV x-ray irradiation match that of Cherenkov radiation. Different angular dependence and spectrum results from that of previous studies on radiation induced light in optical fibres have also been found. The result of the theoretical model agrees with the angle-dependence measurements.

Silva, I.; Pang, G.

2012-06-01

294

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

PubMed

The objective of this study was to evaluate a percutaneous extravascular closure device (StarClose, Abbott Vascular, Redwood City, CA) after brachial endovascular approach. From 2004 to 2006, 29 patients received StarClose for brachial closure. Primary endpoints were successful deployment and absence of procedure-related morbidity, secondary endpoints were brachial artery patency on duplex and absence of late (> 30 days) complications. The device was successfully deployed in all patients. In two patients (6.8%) local complications occurred: one patient developed a large hematoma successfully treated with prolonged compression and a second patient presented with brachial artery occlusion requiring operative intervention. After a mean follow-up of 7.5+/-7.2 months, all patients had a palpable brachial/radial pulse; none had signs of infection, distal embolization or neurological deficits. On ultrasound b-mode imaging, the clip was visible as a 4 mm echolucent area at the outer anterior wall of the artery. Based on the peak systolic velocity ratios between the site of StarClose and proximal brachial artery (mean 1.08+/-0.2), none of the studied patients had a significant stenosis at the site of closure. StarClose is safe and effective in providing hemostasis following interventional procedures through the brachial artery; further advantages include patients comfort and early discharge. PMID:18377837

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

2008-01-01

295

Concomitant Traumatic Spinal Cord and Brachial Plexus Injuries in Adult Patients  

PubMed Central

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.

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

2011-01-01

296

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

USGS Publications Warehouse

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.

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

1989-01-01

297

Effect of solvents on radiation-induced ionic graft polymerization. [Gamma radiation  

SciTech Connect

The influence of various solvents on radiation-induced cationic (grafting of vinyl-n-butyl ether onto polyethylene) and anionic (grafting of 2-methyl-5-vinylpyridine onto polyethylene) graft polymerization was studied. This ionic grafting was performed in thoroughly dried systems at room temperature. It was established that electron-acceptor solvents promote cationic grafting but that electron-donor solvents promote the anionic. A clear correlation between the donor number of solvents and grafting value by the anionic mechanism was shown. There was no correlation between dielectric constants and grafting values. The reaction orders, according to monomer concentraton by 2-methyl-5-vinylpyridine grafting in various solvents, were equal to approximately 1.5 and 2 for the radical and anionic mechanisms, respectively. The effect of solvents on radiation-induced ionic graft polymerization is discussed. The results of this study indicate the correct choice of solvents for radiation-induced ionic grafting.

Kabanov, V.Ya.; Aliev, R.E.; Sidorova, L.P.

1980-03-01

298

Radiation-induced genomic instability and its implications for radiation carcinogenesis  

NASA Technical Reports Server (NTRS)

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.

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

2003-01-01

299

Carotid Stenting for Post-Endarterectomy Restenosis and Radiation-Induced Occlusive Disease  

PubMed Central

Surgical treatment of carotid restenosis and radiation-induced occlusive disease is challenging because of the high morbidity and mortality associated with this procedure. Carotid stenting has been proposed as an alternative approach. We report a series of 8 patients who were treated via the percutaneous approach for either carotid restenosis (n = 4) or radiation-induced occlusive disease (n = 4). Technical success was achieved in all of the cases. There have been no deaths or strokes during the periprocedural or follow-up period. After dilation of the extracranial vessel, 1 patient experienced severe intracranial internal carotid arterial spasm that required stent placement. Wallstents® were used in 6 patients and S.M.A.R.T.™ stents were used in the remaining 2. Restenosis occurred in 2 patients and was treated successfully with redilation or restenting. Carotid stenting appears to be a feasible and safe alternative to surgery for restenosis after carotid endarterectomy and for radiation-induced occlusive disease.

Hernandez-Vila, Eduardo; Strickman, Neil E.; Skolkin, Mark; Toombs, Barry D.; Krajcer, Zvonimir

2000-01-01

300

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

SciTech Connect

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.

Rousseau, Matthieu; Gaugler, Marie-Helene; Rodallec, Audrey; Bonnaud, Stephanie; Paris, Francois [Inserm UMR U892, Centre de Recherche en Cancerologie Nantes-Angers CRCNA, Institut de Recherche Therapeutique IRT-UN, Universite de Nantes, 8 Quai Moncousu, BP 70721, F-44007 (France)] [Inserm UMR U892, Centre de Recherche en Cancerologie Nantes-Angers CRCNA, Institut de Recherche Therapeutique IRT-UN, Universite de Nantes, 8 Quai Moncousu, BP 70721, F-44007 (France); Corre, Isabelle, E-mail: icorre@nantes.inserm.fr [Inserm UMR U892, Centre de Recherche en Cancerologie Nantes-Angers CRCNA, Institut de Recherche Therapeutique IRT-UN, Universite de Nantes, 8 Quai Moncousu, BP 70721, F-44007 (France)] [Inserm UMR U892, Centre de Recherche en Cancerologie Nantes-Angers CRCNA, Institut de Recherche Therapeutique IRT-UN, Universite de Nantes, 8 Quai Moncousu, BP 70721, F-44007 (France)

2011-11-04

301

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

NASA Astrophysics Data System (ADS)

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

Kovalskiy, A.

2003-01-01

302

Radiation-induced degradation of alkyl-substituted polysilanes in solution  

SciTech Connect

Radiation-induced degradation of two alkyl-substituted polysilanes, poly(methyl-n-propyl-silane) and poly(di-n-hexylsilane), has been studied in mixed solvents of n-butyl chloride (BuCl) and tetranhydrofuran (THF). The polysilanes readily degraded in BuCl, while the degradation was strongly suppressed by the addition of a small amount of THF. Mechanistic as well as spectroscopic studies revealed that radical cations of the polysilanes play a more important role than the radical anions as intermediates in the radiation-induced degradation.

Irie, Setsuko [Univ. of Osaka Prefecture (Japan). Research Inst. for Advanced Science and Technology; Irie, Masahiro [Kyushu Univ., Fukuoka (Japan). Inst. of Advanced Material Study

1995-02-13

303

Low-Dose Bevacizumab Is Effective in Radiation-Induced Necrosis  

PubMed Central

Background Radiation-induced necrosis is a complication of brain irradiation. Treatment options are limited. Methods The response to treatment with low-dose bevacizumab in 2 patients with radiation-induced necrosis was reported. Results Both patients with metastatic melanoma, aged 48 and 51 years, had significant symptomatic and radiological improvement with low-dose bevacizumab treatment. Doses as low as 5 mg/kg every 6 weeks and 7.5 mg/kg i.v. every 4 weeks were used and were highly effective. Conclusions Low-dose bevacizumab is a solid option in the management of edema associated with radiation necrosis.

Alessandretti, Matheus; Buzaid, Antonio C.; Brandao, Raphael; Brandao, Erika P.

2013-01-01

304

Antimicrobial fabric adsorbed iodine produced by radiation-induced graft polymerization  

NASA Astrophysics Data System (ADS)

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.

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

2013-03-01

305

Surgical treatment of brachial plexus injuries in adults  

PubMed Central

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

2005-01-01

306

Brachial plexus injury in adults: Diagnosis and surgical treatment strategies  

PubMed Central

Adult post traumatic Brachial plexus injury is unfortunately a rather common injury in young adults. In India the most common scenario is of a young man injured in a motorcycle accident. Exact incidence figures are not available but of the injuries presenting to us about 90% invole the above combination This article reviews peer-reviewed publications including clinical papers, review articles and Meta analysis 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. Results have been discussed and analysed to get an idea of factors influencing final recovery. It appears that time from injury and number of roots involved are most crucial.

Thatte, Mukund R.; Babhulkar, Sonali; Hiremath, Amita

2013-01-01

307

Brachial plexus injury: a descriptive study of american football.  

PubMed

A stinger is a common, yet understudied, injury that involves stretching or compression of the brachial plexus, often occurring during contact sports. Five football teams, including high school, collegiate, and professional teams, completed questionnaires. Questions were designed to obtain descriptive information regarding the nature and consequence of this injury and assess effectiveness of current preventive measures. Three hundred and four surveys were returned with 153 players reporting a stinger in their career (50.3%). The prevalence increased with years played and was most common in running backs (69%), defensive linemen (60%), linebackers (55%), and defensive secondary (54%). Current protective equipment and neck-strengthening programs did not provide protective benefits. Players at greatest risk of developing a stinger include those having played 3 or more years and players whose primary position is running back, defensive back, or defensive lineman. Further study is needed to better evaluate the effectiveness of current preventive measures. PMID:24875339

Starr, Harlan M; Anderson, Blake; Courson, Ron; Seiler, John G

2014-01-01

308

A giant plexiform schwannoma of the brachial plexus: case report  

PubMed Central

We report the case of a patient who noticed muscle weakness in his left arm 5 years earlier. On examination, a biloculate mass was observed in the left supraclavicular area, and Tinel's sign caused paresthesia in his left arm. Magnetic resonance imaging showed a continuous, multinodular, plexiform tumor from the left C5 to C7 nerve root along the course of the brachial plexus to the left brachia. Tumor excision was attempted. The median and musculocutaneous nerves were extremely enlarged by the tumor, which was approximately 40 cm in length, and showed no response to electric stimulation. We resected a part of the musculocutaneous nerve for biopsy and performed latissimus dorsi muscle transposition in order to repair elbow flexion. Morphologically, the tumor consisted of typical Antoni A areas, and immunohistochemistry revealed a Schwann cell origin of the tumor cells moreover, there was no sign of axon differentiation in the tumor. Therefore, the final diagnosis of plexiform Schwannoma was confirmed.

2011-01-01

309

Brachial Plexus Injury from CT-Guided RF Ablation Under General Anesthesia  

SciTech Connect

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.

Shankar, Sridhar, E-mail: shankars@ummhc.org; Sonnenberg, Eric van; Silverman, Stuart G.; Tuncali, Kemal [Brigham and Women's Hospital, Department of Radiology (United States); Flanagan, Hugh L. [Brigham and Women's Hospital, Department of Anesthesia (United States); Whang, Edward E. [Brigham and Women's Hospital, Department of Surgery (United States)

2005-06-15

310

Investigation of brachial plexus traction lesions by peripheral and spinal somatosensory evoked potentials  

Microsoft Academic Search

Peripheral, spinal and cortical somatosensory evoked potentials were recorded in 26 patients with unilateral traction injuries of the brachial plexus ganglia. Of 10 cases explored surgically the recordings correctly anticipated the major site of the lesion in eight.

S J Jones

1979-01-01

311

Neonatal brachial plexus palsy: Incidence, prevalence, and temporal trends.  

PubMed

Epidemiological knowledge of the incidence, prevalence, and temporal changes of neonatal brachial plexuses palsy (NBPP) should assist the clinician, avert unnecessary interventions, and help formulate evidence-based health policies. A summary of 63 publications in the English language with over 17 million births and 24,000 NBPPs is notable for six things. First, the rate of NBPP in the US and other countries is comparable: 1.5 vs. 1.3 per 1000 total births, respectively. Second, the rate of NBPP may be decreasing: 0.9, 1.0 and 0.5 per 1,000 births for publications before 1990, 1990-2000, and after 2000, respectively. Third, the likelihood of not having concomitant shoulder dystocia with NBPP was 76% overall, though it varied by whether the publication was from the US (78%) vs. other countries (47%). Fourth, the likelihood of NBPP being permanent (lasting at least 12 months) was 10-18% in the US-based reports and 19-23% in other countries. Fifth, in studies from the US, the rate of permanent NBPP is 1.1-2.2 per 10,000 births and 2.9-3.7 per 10,000 births in other nations. Sixth, we estimate that approximately 5000 NBPPs occur every year in the US, of which over 580-1050 are permanent, and that since birth, 63,000 adults have been afflicted with persistent paresis of their brachial plexus. The exceedingly infrequent nature of permanent NBPP necessitates a multi-center study to improve our understanding of the antecedent factors and to abate the long-term sequela. PMID:24863027

Chauhan, Suneet P; Blackwell, Sean B; Ananth, Cande V

2014-06-01

312

Ultrasound Measurement of Brachial Artery Elasticity Before Hemodialysis Access Placement  

PubMed Central

Objectives Successful hemodialysis requires reliable vascular access that can deliver adequate blood flow. An arteriovenous fistula is preferred for access because of its longevity and low frequency of complications, but up to 60% of arteriovenous fistulas created surgically are never suitable for hemodialysis because of nonmaturation (insufficient vascular dilatation). Decreased arterial elasticity may impair dilatation, thereby affecting fistula maturation. This study evaluated the feasibility of brachial artery elasticity measurement in patients with chronic kidney disease obtained during routine preoperative mapping ultrasound (US) imaging before hemodialysis access placement and compared the measurements to those obtained in healthy volunteers. Methods Brachial artery functional US studies were collected from 75 patients undergoing routine preoperative mapping for hemodialysis access and 50 healthy volunteers. Vascular strain was calculated from the change in intima-media thickness between end systole and end diastole, and vascular stress was estimated from the pulse pressure. Assuming a linear elastic medium, the elastic modulus was estimated as the ratio of vascular stress to strain. Results Elastic modulus measurements were significantly higher in patients than in volunteers (130 versus 100 kPa; P = .01). With combined volunteer and patient data, there was a significant correlation between elasticity and systolic blood pressure (R2 = 0.23; P < .001). Elasticity was correlated with age in volunteers but not in patients (R2 = 0.14; P = .017; R2 < .001; P = .829, respectively). Conclusions This analysis of clinical arterial vessel biomechanics shows that a noninvasive US measurement can detect elastic modulus differences between patients with chronic kidney disease and healthy individuals. Future studies will correlate the elastic modulus with histologic characteristics and eventual arteriovenous fistula maturation, which may provide supplemental information on arterial biomechanical properties as a useful addition to current predictors of fistula success.

Sorace, Anna G.; Robbin, Michelle L.; Umphrey, Heidi; Abts, Carl A.; Berry, Joel L.; Lockhart, Mark E.; Allon, Michael; Hoyt, Kenneth

2012-01-01

313

OCT/PS-OCT imaging of brachial plexus neurovascular structures  

NASA Astrophysics Data System (ADS)

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

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

2004-07-01

314

Treatment of shoulder sequelae in brachial plexus birth injury  

PubMed Central

Background Many children with permanent brachial plexus birth injury (BPBI) develop shoulder problems, with subsequent joint deformity without treatment. We assessed the indications and outcome of shoulder operations for BPBI. Patients and methods 31 BPBI patients who had undergone a shoulder operation in our hospital between March 2002 and December 2005 were included in the study. Relocation of the humeral head had been performed in 13 patients, external rotation osteotomy of the humerus in 5 patients, subscapular tendon lengthening in 5 patients, and teres major transposition in 8 patients. Subjective results were registered. Shoulder range of motion was measured, and function assessed according to the Mallet scale. Magnetic resonance imaging (MRI) was performed pre- and postoperatively. Glenoscapular angle (GSA) and percentage of humeral head anterior to the middle of the glenoid fossa (PHHA) were measured. Congruency of the glenohumeral joint (GHJ) was estimated. The mean follow-up time was 3.8 (1.7–6.8) years. Results At follow-up, the subjective result was satisfactory in 30 of the 31 patients. There were 4 failures, which in retrospect were due to wrong choice of surgical method in 3 of these 4 patients. Mean increase in Mallet score was 5.5 after successful relocation, 1.4 after rotation osteotomy, 2.2 after subscapular tendon lengthening, and 3.1 after teres major transposition. Congruency of the shoulder joint improved in 10 of 13 patients who had undergone a relocation operation, with mean improvement in GSA of 33º and mean increase in PHHA of 25%. There were no substantial changes in congruency of the glenohumeral joint in patients treated with other operation types. Interpretation Restriction of the range of motion and malposition of the glenohumeral joint can be improved surgically in brachial plexus birth injury. Remodeling of the joint takes place after successful relocation of the humeral head in young patients.

2011-01-01

315

Cross-Sectional Relations of Multiple Biomarkers From Distinct Biological Pathways to Brachial Artery Endothelial Function  

Microsoft Academic Search

Background—Endothelial dysfunction is a critical intermediate phenotype in the pathogenesis of cardiovascular disease. We evaluated the relative contributions of distinct biological pathways to interindividual variation in endothelial function by relating prototype biomarkers (representing these pathways) to brachial artery vasodilator function. Methods and Results—We investigated the cross-sectional relations of a panel of 7 biomarkers measured at a routine examination to brachial

Sekar Kathiresan; Philimon Gona; Martin G. Larson; Joseph A. Vita; Gary F. Mitchell; Geoffrey H. Tofler; Daniel Levy; Christopher Newton-Cheh; Thomas J. Wang; Emelia J. Benjamin; Ramachandran S. Vasan

2010-01-01

316

The reliability of toe systolic pressure and the toe brachial index in patients with diabetes  

PubMed Central

Background The Ankle Brachial Index is a useful clinical test for establishing blood supply to the foot. However, there are limitations to this method when conducted on people with diabetes. As an alternative to the Ankle Brachial Index, measuring Toe Systolic Pressures and the Toe Brachial Index have been recommended to assess the arterial blood supply to the foot. This study aimed to determine the intra and inter-rater reliability of the measurement of Toe Systolic Pressure and the Toe Brachial Index in patients with diabetes using a manual measurement system. Methods This was a repeated measures, reliability study. Three raters measured Toe Systolic Pressure and the Toe Brachial Index in thirty participants with diabetes. Measurement sessions occurred on two occasions, one week apart, using a manual photoplethysmography unit (Hadeco Smartdop 45) and a standardised measurement protocol. Results The mean intra-class correlation for intra-rater reliability for toe systolic pressures was 0.87 (95% LOA: -25.97 to 26.06 mmHg) and the mean intra-class correlation for Toe Brachial Indices was 0.75 (95% LOA: -0.22 to 0.28). The intra-class correlation for inter-rater reliability was 0.88 for toe systolic pressures (95% LOA: -22.91 to 29.17.mmHg) and 0.77 for Toe Brachial Indices (95% LOA: -0.21 to 0.22). Conclusion Despite the reasonable intra-class correlation results, the range of error (95% LOA) was broad. This raises questions regarding the reliability of using a manual sphygmomanometer and PPG for the Toe Systolic Pressure and Toe Brachial Indice.

2010-01-01

317

Relationship between brachial-ankle pulse wave velocity and cardiovascular risk factors of the metabolic syndrome  

Microsoft Academic Search

In this study, we investigated the association between brachial-ankle pulse wave velocity (baPWV), a novel non-invasive means of measuring atherosclerosis, and the cardiovascular risk factors of the metabolic syndrome. The study group comprised of 368 Koreans without history of diabetes or hypertension. Anthropometric parameters, blood pressure, fasting blood glucose (FBG), lipid profiles, ankle-brachial pressure index (ABI), and baPWV were measured

K. M. Choi; K. W. Lee; J. A. Seo; J. H. Oh; S. G. Kim; N. H. Kim; D. S. Choi; S. H. Baik

2004-01-01

318

Impact of Metabolic Syndrome on Brachial-Ankle Pulse Wave Velocity in Japanese  

Microsoft Academic Search

The aim of this study was to determine the effect of metabolic syndrome on brachial-ankle pulse wave velocity (baPWV) by using the new guidelines for diagnosis of this syndrome in Japan. We examined 525 men and women without a history of cardiovascular disease or cancer, and an ankle-brachial index<0.9. The baPWV was measured using a device (Form PWV\\/ABI) that simultaneously

Akiko Tsubakimoto; Isao Saito; Toshifumi Mannami; Yoshihiko Naito; Shinobu Nakamura; Yoshiko Dohi; Kunio Yonemasu

2006-01-01

319

A Case of True Brachial Artery Aneurysm in an Elderly Male  

PubMed Central

Brachial artery aneurysms are relatively rare and are mostly pseudoaneurysms rather than true aneurysms, as true aneurysms are even rarer entities. Patients can be asymptomatic, or present with pulsatile masses, or ischemia due to associated thromboembolic complications. Distal embolism can occur with transient or minimal ischemic symptoms; however, aneurysm itself can thrombose entirely. The authors report a case of upper limb acute ischemia caused by true brachial artery aneurysm thrombosis in an elderly man, managed by reconstructive vascular surgery.

A. Fakhree M., Bassir; Azhough, Ramin; Hafez Quran, Farnaz

2012-01-01

320

Effect of fluvastatin on endothelium-dependent brachial artery vasodilation in patients after renal transplantation  

Microsoft Academic Search

Effect of fluvastatin on endothelium-dependent brachial artery vasodilation in patients after renal transplantation.BackgroundHypercholesterolemia may affect both endothelial function and arterial distensibility (DC). Renal transplant recipients (NTX) exhibit advanced structural and functional alterations of arterial vessel walls. The aim of this double-blind, randomized trial was to evaluate the effects of fluvastatin (FLU) on brachial artery flow-mediated vasodilation (FMD) and DC in

Martin Hausberg; Markus Kosch; Frank Stam; Stefan Heidenreich; Klaus Kisters; Karl Heinz Rahn; Michael Barenbrock

2001-01-01

321

The use of train of four monitoring for clinical evaluation of the axillary brachial plexus block.  

PubMed

The axillary approach of brachial plexus anesthesia is the most commonly used technique for forearm and hand surgery. Dynamometer is known as objective test for the clinical assessment of motor block of the nerves in brachial plexus block. However, the use of this device may not always be practical in operating room. The train-of-four (TOF) test is a non-invasive peripheral nerve stimulator that shows the level of motor block of muscle relaxants. The aim of the study is to investigate the use of TOF testing as a peripheral nerve stimulator for objective clinical evaluation of motor block at axillary brachial plexus block. 44 patients were randomized according to the development of partial or complete motor in the axillary brachial plexus block. The nerves were selectively localized by nerve stimulation and ultrasound guidance. After obtaining an appropriate peripheral motor response, predetermined volumes of bupivacaine were selectively injected to the 4 nerves. Sensory, motor block levels and TOF values were measured at 10th, 20th, 30th minutes immediately after the axillary brachial plexus block. TOF values were gradually decreased and significant difference was observed between the development of a complete and partial motor block at 30th minute. TOF values were also significantly less in patients of complete sensory block than the patients of partial sensory block at 30th minute. The use of TOF monitoring may be beneficial to assess the objective clinical effect of motor block in the patients with axillary brachial plexus nerve block. PMID:24126617

Sen, Selda; Sari, Sinem; Kurt, Imran; Cobanoglu, Mutlu

2014-06-01

322

Radiation-induced eco-compatible sulfonated starch\\/acrylic acid graft copolymers for sucrose hydrolysis  

Microsoft Academic Search

Radiation-induced graft-copolymers capable of hosting sulfonic groups and having more effective catalytic activity towards sucrose hydrolysis were prepared. Acrylic acid monomer (AA) was copolymerized with sulfonated starch (SS) at different compositions using ionizing radiation. Swelling behavior of the prepared copolymers at different environmental conditions was studied as well as thermal stability. The hydrolysis of sucrose to glucose and fructose by

H. A. Abd El-Rehim; D. A. Diaa

323

Morphogenesis of the Radiation-Induced Mutant Limb Deformity (Ld) of the Common Mouse.  

National Technical Information Service (NTIS)

Findings obtained in the thoracic and pelvic extremities of mice of the incest strain C57B1/10; i.e. animals homozygous with regard to the radiation-induced mutation 'limb deformity', are summarized and compared with the findings in non-deformed mice. Fur...

J. Selow W. Winkler

1980-01-01

324

Cell Cycle Dependence of Ionizing Radiation-Induced DNA Deletions and Antioxidant Radioprotection in Saccharomyces cerevisiae  

PubMed Central

The yeast DEL assay is an effective method for measuring intrachromosomal recombination events resulting in DNA deletions that when occurring in mammalian cells are often associated with genomic instability and carcinogenesis. Here we used the DEL assay to measure ?-ray-induced DNA deletions throughout different phases of yeast culture growth. Whereas yeast survival differed by only up to twofold throughout the yeast growth phase, proliferating cells in lag and early exponential growth phases were tenfold more sensitive to ionizing radiation-induced DNA deletions than cells in stationary phase. Radiation-induced DNA deletion potential was found to correlate directly with the fraction of cells in S/G2 phase. The ability of the antioxidants l-ascorbic acid and DMSO to protect against radiation-induced DNA deletions was also measured within the different phases of yeast culture growth. Yeast cells in lag and early exponential growth phases were uniquely protected by antioxidant treatment, whereas nondividing cells in stationary phase could not be protected against the induction of DNA deletions. These results are compared with those from mammalian cell studies, and the implications for radiation-induced carcinogenesis and radioprotection are discussed.

Hafer, Kurt; Rivina, Leena; Schiestl, Robert H.

2013-01-01

325

Modification of gene expression by dietary antioxidants in radiation-induced apoptosis of mice splenocytes.  

PubMed

The modification of radiation-induced apoptosis in splenocytes by a vitamin-containing dietary supplement was studied. For 45 days prior to irradiation at a lethal dose of 6 Gy, mice received a dietary supplement containing vitamins with antioxidant properties and microelements. The expression of TRPM-2 (a marker for programmed cell death), bcl-2 (the product of which has been shown to prevent apoptosis), superoxide dismutase, and catalase genes was studied at different time intervals after irradiation. Radiation-induced alterations in gene expression were different in the control and the antioxidant mixture-fed mice. The antioxidant mixture administration resulted in an inhibition of TRPM-2 expression both before and after irradiation. The bcl-2 mRNA content steadily increased after irradiation in splenocytes from antioxidant mixture-fed mice, while in the control group 2-h after irradiation only trace amount of bcl-2 mRNA was detected. In splenocytes from control mice, the expression of superoxide dismutase and catalase genes significantly decreased within 2-h after irradiation; whereas in mice receiving the antioxidant mixture, inhibition of catalase gene expression was not as prominent. The expression of superoxide dismutase gene was still high 24-h after irradiation. The antioxidant administration decreased the radiation-induced apoptosis and delayed internucleosomal fragmentation of DNA. Our data suggest that radiation-induced alteration of gene expression is, at least in part, determined by reactive oxygen species. PMID:10232832

Ushakova, T; Melkonyan, H; Nikonova, L; Afanasyev, V; Gaziev, A I; Mudrik, N; Bradbury, R; Gogvadze, V

1999-04-01

326

Effect of chemical doping on the radiation-induced conductivity of polyethylene terephthalate  

SciTech Connect

A large decrease in the radiation-induced conductivity of polyethylene terephthalate was produced upon doping films with an electron acceptor molecule. Transient x-ray photoconductivity data verify that this impurity acts as a deep trap. Charge transfer occurs in the doped dielectric which may be associated with this trapping process.

Kurtz, S.R.; Arnold C. Jr.; Hughes, R.C.

1983-12-15

327

Radiation induced failures of complementary metal oxide semiconductor containing pacemakers: a potentially lethal complication  

Microsoft Academic Search

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

Alan A. Lewin; Christopher F. Serago; James G. Schwade; Andre A. Abitbol; Stephen C. Margolis

1984-01-01

328

Colitis cystica profunda occurring in a radiation-induced colonic stricture  

SciTech Connect

Localized colitis cystica profunda developed in a fibrotic radiation-induced colonic stricture 17 years after pelvic radiation for squamous carcinoma of cervix. This uncommon pathologic entity must be distinguished from invasive adenocarcinoma of colon, and colonic radiation injury should be included with other conditions associated with colitis cystica profunda.

Gardiner, G.W.; McAuliffe, N.; Murray, D.

1984-03-01

329

Ionizing radiation-induced copolymerization of 2-ethylhexyl acrylate and acrylic acid and ionomer formation  

Microsoft Academic Search

The ionizing radiation-induced polymerization of acrylate esters is a technique employed for the curing of such materials for a variety of adhesive, coating, ink, and lithographic applications. The work presented in this dissertation involves the synthesis of a copolymer composed of 2-ethylhexyl acrylate (2-EHA) and acrylic acid (AA) using pulsed electron beam and gamma irradiation. The structure and synthesis kinetics

Alia Weaver

2007-01-01

330

Study on radiation-induced grafting of styrene onto chitin and chitosan  

Microsoft Academic Search

Radiation-induced grafting of styrene onto chitin and chitosan powder was performed at room temperature. The effect of various conditions such as absorbed dose, solvent and oxygen on grafting was investigated. The grafting yield increased with the increase in absorbed dose. At the same dose, the grafting yield of styrene on chitosan was higher than that on chitin. The grafting reaction

Liu Pengfei; Zhai Maolin; W. Jilan

2001-01-01

331

Radiation-induced electrical conductivity in MgAl2O4 spinel.  

National Technical Information Service (NTIS)

The d.c. electrical conductivity of high purity, polycrystalline MgAl(sub 2)O(sub 4) spinel of 99.5% theoretical density has been measured during irradiation by 18 MeV protons at reactor relevant ionization dose rates. The radiation-induced conductivity (...

G. P. Pells

1990-01-01

332

Mouse models and quantitative trait loci of susceptibility to bleomycin- and radiation-induced pulmonary fibrosis  

Microsoft Academic Search

Radiotherapy involving the thoracic cavity and chemotherapy with the drug bleomycin are both dose limited by the development of pulmonary fibrosis. From evidence that there is variation in the population in susceptibility to pulmonary fibrosis, and animal data, it was hypothesized that individual variation in susceptibility to bleomycin-induced, or radiation-induced, pulmonary fibrosis is, in part, genetically controlled. In this thesis

Christina Kathleen Haston

1997-01-01

333

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

SciTech Connect

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.

Starzewski, Jacek J. [Department of General and Colorectal Surgery, Medical University of Silesia, Sosnowiec (Poland); Pajak, Jacek T. [Department of Pathology, Medical University of Silesia, Katowice (Poland); Pawelczyk, Iwona [Department of General and Colorectal Surgery, Medical University of Silesia, Sosnowiec (Poland); Lange, Dariusz [Department of Tumor Pathology, Comprehensive Cancer Center Division, Gliwice (Poland); Golka, Dariusz [Department of Pathology, Medical University of Silesia, Katowice (Poland)]. E-mail: dargolka@wp.pl; Brzeziska, Monika [Department of General and Colorectal Surgery, Medical University of Silesia, Sosnowiec (Poland); Lorenc, Zbigniew [Department of General and Colorectal Surgery, Medical University of Silesia, Sosnowiec (Poland)

2006-03-01

334

3D ultrasound Nakagami imaging for radiation-induced vaginal fibrosis  

NASA Astrophysics Data System (ADS)

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.

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

2014-03-01

335

Effect of ozone oxidative preconditioning in preventing early radiation-induced lung injury in rats  

PubMed Central

Ionizing radiation causes its biological effects mainly through oxidative damage induced by reactive oxygen species. Previous studies showed that ozone oxidative preconditioning attenuated pathophysiological events mediated by reactive oxygen species. As inhalation of ozone induces lung injury, the aim of this study was to examine whether ozone oxidative preconditioning potentiates or attenuates the effects of irradiation on the lung. Rats were subjected to total body irradiation, with or without treatment with ozone oxidative preconditioning (0.72 mg/kg). Serum proinflammatory cytokine levels, oxidative damage markers, and histopathological analysis were compared at 6 and 72 h after total body irradiation. Irradiation significantly increased lung malondialdehyde levels as an end-product of lipoperoxidation. Irradiation also significantly decreased lung superoxide dismutase activity, which is an indicator of the generation of oxidative stress and an early protective response to oxidative damage. Ozone oxidative preconditioning plus irradiation significantly decreased malondialdehyde levels and increased the activity of superoxide dismutase, which might indicate protection of the lung from radiation-induced lung injury. Serum tumor necrosis factor alpha and interleukin-1 beta levels, which increased significantly following total body irradiation, were decreased with ozone oxidative preconditioning. Moreover, ozone oxidative preconditioning was able to ameliorate radiation-induced lung injury assessed by histopathological evaluation. In conclusion, ozone oxidative preconditioning, repeated low-dose intraperitoneal administration of ozone, did not exacerbate radiation-induced lung injury, and, on the contrary, it provided protection against radiation-induced lung damage.

Bakkal, B.H.; Gultekin, F.A.; Guven, B.; Turkcu, U.O.; Bektas, S.; Can, M.

2013-01-01

336

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

SciTech Connect

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.

Du Shisuo; Qiang Min [Department of Radiation Oncology, Zhongshan Hospital, Fudan University, Shanghai (China); Zeng Zhaochong, E-mail: zeng.zhaochong@zs-hospital.sh.c [Department of Radiation Oncology, Zhongshan Hospital, Fudan University, Shanghai (China); Ke Aiwu; Ji Yuan [Liver Cancer Institute, Zhongshan Hospital, Fudan University, Shanghai (China); Zhang Zhengyu [Department of Radiation Oncology, Zhongshan Hospital, Fudan University, Shanghai (China); Zeng Haiying [Department of Pathology, Zhongshan Hospital, Fudan University, Shanghai (China); Liu Zhongshan [Department of Radiation Oncology, Zhongshan Hospital, Fudan University, Shanghai (China)

2010-03-15

337

Study on slow release anti-cancer drugs prepared by radiation induced polymerization  

Microsoft Academic Search

This paper reports the research results which the anticancer drugs Ara-C with controlled slow release were made by radiation induced polymerization of monomers such as methacrylates at room temperature. Our studies showed that not only hydrophilic synthetic polymers but also hydrophobic polymers such as hydrophobic methacrylates (including MMA, EMA, and BMA) could be used to the immobilization. In vitro the

Xie Huaijiang; Song Juzhong; Peng Tao

1993-01-01

338

INTERRELATIONS OF NUCLEIC ACID AND PROTEIN SYNTHESES IN RADIATION INDUCED MUTATION INDUCTION IN BACTERIA  

Microsoft Academic Search

During the past decade evidence has accumulated that an appreciable ; portion of radiation-induced mutations are due to chemical effects of radiation ; on sensitive metabolites. The shape of induced mutation frequency curves ; suggests that intracellular radiation-sensitive material is modified by radiation. ; This material is probably both limited in quantity and destroyed by radiat high ; doses of

F. L. Haas; C. O. Doudney

1958-01-01

339

Curcumin Attenuates Radiation-Induced Inflammation and Fibrosis in Rat Lungs  

PubMed Central

A beneficial radioprotective agent has been used to treat the radiation-induced lung injury. This study was performed to investigate whether curcumin, which is known to have anti-inflammatory and antioxidant properties, could ameliorate radiation-induced pulmonary inflammation and fibrosis in irradiated lungs. Rats were given daily doses of intragastric curcumin (200 mg/kg) prior to a single irradiation and for 8 weeks after radiation. Histopathologic findings demonstrated that macrophage accumulation, interstitial edema, alveolar septal thickness, perivascular fibrosis, and collapse in radiation-treated lungs were inhibited by curcumin administration. Radiation-induced transforming growth factor-?1 (TGF-?1), connective tissue growth factor (CTGF) expression, and collagen accumulation were also inhibited by curcumin. Moreover, western blot analysis revealed that curcumin lowered radiation-induced increases of tumor necrosis factor-? (TNF-?), TNF receptor 1 (TNFR1), and cyclooxygenase-2 (COX-2). Curcumin also inhibited the nuclear translocation of nuclear factor-? B (NF-?B) p65 in radiation-treated lungs. These results indicate that long-term curcumin administration may reduce lung inflammation and fibrosis caused by radiation treatment.

Cho, Yu Ji; Yi, Chin Ok; Jeon, Byeong Tak; Jeong, Yi Yeong; Kang, Gi Mun; Lee, Jung Eun

2013-01-01

340

Radiation-induced sarcomas following radiotherapy for breast cancer: six case reports and a review of the literature  

Microsoft Academic Search

Seven patients with radiation-induced sarcomas (RIS) following radiotherapy (RT) for breast cancer were treated between 1983 and 1994 at the ‘Henri Mondor’ University Hospital (France). All patients underwent surgery and RT for breast cancer. Only one patient received chemotherapy (CT). All patients at the time of diagnosis of RIS were free of disease. Radiation-induced sarcoma appeared with a latency period

Y. M. Kirova; F. Feuilhade; E. Calitchi; Y. Otmezguine; J.-P. Le Bourgeois

1998-01-01

341

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

SciTech Connect

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

Jiao, Zhijie [ORNL; Busby, Jeremy T [ORNL; Was, Gary S [ORNL; Jiao, Zhijie [University of Michigan

2010-01-01

342

Influence of topoisomerase II on the formation of oxygen-dependent radiation-induced DNA damage.  

PubMed Central

Several laboratories have recently demonstrated the feasibility of using radiation-induced DNA strand breaks (SBs) and DNA-protein cross-links (DPCs) to detect and quantify hypoxic cells in tumours and normal tissues. However, if radiation-induced SBs and DPCs are going to provide reasonable estimates of the hypoxic fraction or fractional hypoxic volume of tumours and normal tissues, their formation as a function of the oxygen concentration must be relatively independent of biological factors such as cell type, proliferative status or the composition and properties of proteins that are intimately associated with the DNA. In the present study, the shape of the oxygen dependence curves and the K(m) values for radiation-induced SBs and DPCs were measured by alkaline elution for two human leukaemia cell lines, CEM and CEM/VM-1, whose nuclear matrix-associated topoisomerase II varied substantially in quantity, activity and binding properties. The sigmoidal shape of the oxygen dependence curves, the K(m) for sB formation (approximately 0.027 mM), and the K(m) for DPC formation (approximately 0.064 mM) were identical for both of these human leukaemia cell lines. Consequently, the quantity and properties of topoisomerase II had no measurable influence on the oxygen-dependent formation of radiation-induced SBs and DPCs. These data suggest that varying levels of nuclear matrix-associated proteins and DNA binding proteins will not be a complicating factor when using radiation-induced SBs and DPCs for estimating the hypoxic fraction or fractional hypoxic volume of tumours and normal tissues.

Zhang, H.; Wheeler, K. T.

1996-01-01

343

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

SciTech Connect

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.

Lee, Ji-Hyun [Laboratory of Radiation Effect, Korea Institute of Radiological and Medical Sciences, Seoul 139-706 (Korea, Republic of); Koh, Yeon A. [Laboratory of Radiation Effect, Korea Institute of Radiological and Medical Sciences, Seoul 139-706 (Korea, Republic of); Cho, Chul-Koo [Laboratory of Radiation Effect, Korea Institute of Radiological and Medical Sciences, Seoul 139-706 (Korea, Republic of); Lee, Su-Jae [Laboratory of Radiation Effect, Korea Institute of Radiological and Medical Sciences, Seoul 139-706 (Korea, Republic of); Lee, Yun-Sil [Laboratory of Radiation Effect, Korea Institute of Radiological and Medical Sciences, Seoul 139-706 (Korea, Republic of); Bae, Sangwoo [Laboratory of Radiation Effect, Korea Institute of Radiological and Medical Sciences, Seoul 139-706 (Korea, Republic of)]. E-mail: swbae@kcch.re.kr

2005-11-11

344

A shuttle vector system for studying ionizing radiation-induced mutagenesis in mammalian cells.  

PubMed

A shuttle vector system was developed to quantitate and analyze ionizing radiation-induced mutation in mammalian host cells, COS-1 and CV-1. The shuttle vector pSV2-lacY, which was constructed to detect both point mutations and deletions, was irradiated in vitro with 60Co gamma rays before introduction into unirradiated host cells. The plasmid was then isolated and reintroduced into HB101 (lacY-) bacterial host cells for identification of mutated lacY marker genes. Gamma-irradiation produced a decrease of the survival (recovery) and an increase of mutation of the shuttle vector. The mutated shuttle vector molecules were examined for structural changes by means of restriction endonuclease digestion and agarose gel electrophoresis. A dose dependent increase was observed in the percentages of gross alteration events of total mutations in mammalian host. This system will be useful for studies of ionizing radiation-induced mutagenesis. PMID:8360857

Muraiso, C; Mudgett, J S; Matsudaira, H; Strniste, G F

1993-06-01

345

The potential influence of radiation-induced microenvironments in neoplastic progression  

NASA Technical Reports Server (NTRS)

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.

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

1998-01-01

346

Evaluating radiation induced noise effects on pixelated sensors for the National Ignition Facility  

NASA Astrophysics Data System (ADS)

The National Ignition Facility (NIF) utilizes several different pixelated sensor technologies for various measurement systems that include alignment cameras, laser energy sensors, and high-speed framing cameras. These systems remain in the facility where they are exposed to 14MeV neutrons during a NIF shot. The image quality of the sensors degrades as a function of radiation-induced damage. This article reports on a figure-of-merit technique that aids in the tracking of the performance of pixelated sensors when exposed to neutron radiation from NIF. The sensor dark current growth can be displayed over time in a 2D visual representation for tracking radiation induced damage. Predictions of increased noise as a function of neutron fluence for future NIF shots allow simulation of reduced performance for each of the individual camera applications. This predicted longevity allows for proper management of the camera systems.

Datte, Philip; Manuel, Anastacia M.; Eckart, Mark; Jackson, Mark; Khater, Hesham; Newton, Mark

2013-09-01

347

Radiation-induced chondrosarcomas: a case report with review of literature.  

PubMed

Radiation therapy has become an important component of various cancer treatments. The development of second malignancy as a result of radiation therapy is a well-known sinister complication. However, radiation-induced sarcomas (RIS) are rare complications of radiation therapy. The timescale between completion of the radiotherapy and the development of a second malignancy, known as the latent period, can vary widely from as little as 5 years to 50 years later. Radiation-induced sarcomas per se are very rare and those with histomorphology of chondrosarcomas are even rarer. We report a rare case of RIS of left iliac bone in a 62-year-old lady after combined chemotherapy and external beam radiation therapy for cervical carcinoma (stage IIb). This case is being reported for its extreme rarity, vivid histology and clinical presentation. PMID:21119289

Gupta, G; Hafiz, A; Gandhi, J S

2010-01-01

348

A kinetic-based model of radiation-induced intercellular signalling.  

PubMed

It is now widely accepted that intercellular communication can cause significant variations in cellular responses to genotoxic stress. The radiation-induced bystander effect is a prime example of this effect, where cells shielded from radiation exposure see a significant reduction in survival when cultured with irradiated cells. However, there is a lack of robust, quantitative models of this effect which are widely applicable. In this work, we present a novel mathematical model of radiation-induced intercellular signalling which incorporates signal production and response kinetics together with the effects of direct irradiation, and test it against published data sets, including modulated field exposures. This model suggests that these so-called "bystander" effects play a significant role in determining cellular survival, even in directly irradiated populations, meaning that the inclusion of intercellular communication may be essential to produce robust models of radio-biological outcomes in clinically relevant in vivo situations. PMID:23349919

McMahon, Stephen J; Butterworth, Karl T; Trainor, Colman; McGarry, Conor K; O'Sullivan, Joe M; Schettino, Giuseppe; Hounsell, Alan R; Prise, Kevin M

2013-01-01

349

A Kinetic-Based Model of Radiation-Induced Intercellular Signalling  

PubMed Central

It is now widely accepted that intercellular communication can cause significant variations in cellular responses to genotoxic stress. The radiation-induced bystander effect is a prime example of this effect, where cells shielded from radiation exposure see a significant reduction in survival when cultured with irradiated cells. However, there is a lack of robust, quantitative models of this effect which are widely applicable. In this work, we present a novel mathematical model of radiation-induced intercellular signalling which incorporates signal production and response kinetics together with the effects of direct irradiation, and test it against published data sets, including modulated field exposures. This model suggests that these so-called “bystander” effects play a significant role in determining cellular survival, even in directly irradiated populations, meaning that the inclusion of intercellular communication may be essential to produce robust models of radio-biological outcomes in clinically relevant in vivo situations.

McMahon, Stephen J.; Butterworth, Karl T.; Trainor, Colman; McGarry, Conor K.; O'Sullivan, Joe M.; Schettino, Giuseppe; Hounsell, Alan R.; Prise, Kevin M.

2013-01-01

350

Immunologic inhibition of ultraviolet radiation-induced tumor suppressor cell activity  

SciTech Connect

Long-term exposure of C3H mice to ultraviolet radiation resulted in the formation of suppressor T cells that recognize ultraviolet radiation-induced regressor skin cancers as a class before the appearance of overt tumors. Administration of monoclonal antibodies to the product of the I-Jk subregion of the major histocompatibility complex or low doses of cyclophosphamide in vivo inhibited the development or activity of these cells. This activity of the monoclonal antibody was eliminated by adsorption on B10.BR (I-Jk) but not B10.D2 (I-Jd) splenocytes. These findings provide evidence that elements expressing the I-J determinant are important in regulating the host response prior to the overt development of ultraviolet radiation-induced skin cancers and suggest novel therapeutic approaches to malignancies or other diseases involving suppressor T cells in their pathogenesis.

Granstein, R.D.; Parrish, J.A.; McAuliffe, D.J.; Waltenbaugh, C.; Greene, M.I.

1984-05-11

351

Calculation of radiation-induced deformation in the ITER vacuum vessel  

NASA Astrophysics Data System (ADS)

Numerical calculation was carried out to evaluate the radiation induced deformation at the blanket side of the vacuum vessel (120°C) and the rear portion of the blanket module (200°C) in ITER. The calculation was performed for solution-annealed 316 stainless steel mainly at 1×10 -9 dpa/s and 100 MPa. Enhanced transient creep characteristic of the low temperature irradiation is evident at 120°C. However, the total accumulated creep strain in the vacuum vessel is only below 0.01% for the lifetime irradiation so that serious consequence would not be anticipated. At the rear portion of the blanket the creep strain would be about 0.01% and not serious either. Radiation-induced stress relaxation at the vacuum vessel is only several per cent during the lifetime. At the rear portion of the blanket, on the other hand, the relaxation could be of the order of 10% and should not be completely neglected.

Nagakawa, Johsei

1998-10-01

352

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

PubMed

We have investigated the formation of cascade clusters and structural changes in them by means of electron irradiation following ion irradiation in an austenitic stainless steel. Almost all of the cascade clusters, which were introduced by the ion irradiation, grew to form interstitial-type dislocation loops or vacancy-type stacking fault tetrahedra after electron irradiation at 623 K, whereas a few of the dot-type clusters remained in the matrix. It was possible to recognize the concentration of Ni and Si by radiation-induced segregation around the dot-type clusters. After electron irradiation at 773 K, we found that some cascade clusters became precipitates (delta-Ni2Si) due to radiation-induced precipitation. This suggests that the cascade clusters could directly become precipitation sites during irradiation. PMID:12741490

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

2003-01-01

353

Radiation induced darkening of the optical elements in the Startracker camera  

SciTech Connect

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

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

1993-03-01

354

C/EBP? Deficiency Sensitizes Mice to Ionizing Radiation-Induced Hematopoietic and Intestinal Injury.  

PubMed

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/EBP? is implicated in regulation of these same processes, but its role in radiation response is not known. We investigated the role of C/EBP? 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 ?-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/EBP? in promoting the response to radiation-induced DNA-damage and in protecting hematopoietic and intestinal tissues from radiation-induced injury. PMID:24747529

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

2014-01-01

355

The impact of trastuzumab on radiation-induced pulmonary fibrosis: results of an experimental study  

Microsoft Academic Search

There are no data regarding the late toxicity of trastuzumab (T) administration with radiotherapy (RT). In this experimental\\u000a study, we aimed to asses if concurrent or sequential administration of T has any impact for the development of radiation-induced\\u000a pulmonary fibrosis in rats. Fifty-four female Wistar-albino rats were divided into 6 groups. First group of rats (Group 1;\\u000a concurrent T) had

N. S. Bese; C. Umay; S. Serdengecti; N. Kepil; N. Sut; T. Altug; A. Ober

2010-01-01

356

Radiation-induced segregation and the compositional dependence of swelling in Fe-Ni-Cr alloys  

Microsoft Academic Search

When alloys based on the Fe-Ni-Cr system are subjected to irradiation at high temperatures a substantial amount of elemental segregation occurs. Two categories of segregation have been observed, one involving radiation-induced precipitation or changes in precipitate composition, and another involving the establishment of compositional gradients near microstructural sinks. While segregation into precipitate phases is known to strongly influence the development

W. F. Wolfer; F. A. Garner; L. E. Thomas

1982-01-01

357

Effect of dietary vitamin C on radiation induced damage to the testis  

Microsoft Academic Search

We have investigated the ability of dietary vitamin C (ascorbic acid) to mitigate radiation induced damage to the testis arising from exposure to x-rays or the Auger emitting radionuclide 114mIn (half-life 50 days). Male mice were maintained on a normal or an ascorbate enriched diet (1% by weight) for 5 days then irradiated with 3 Gy 300kVp x-rays or injected

Katharine P. Hoyes; Ian D. Morris; Harbans L. Sharma; Jolyon H. Hendry

1995-01-01

358

Evidence of Radiation-Induced Dopant Neutralization in Partially-Depleted SOI NMOSFETs  

Microsoft Academic Search

Radiation-induced dopant passivation is evidenced for the first time in partially-depleted SOI n-channel MOSFETs. Isochronal annealing experiments following 10 Mrad(SiO2) irradiation demonstrate that the neutralization of boron atoms in the NMOSFET body is most pronounced in the 125degC-150degC temperature range. This results in an abrupt decrease of the threshold voltage and the subthreshold swing, due to the transition of the

Kerem Akarvardar; Ronald D. Schrimpf; Daniel M. Fleetwood; Sorin Cristoloveanu; Pierre Gentil; Benjamin J. Blalock

2007-01-01

359

Calculation of radiation-induced DNA damage from photons and tritium beta-particles  

Microsoft Academic Search

Radiation-induced damage in nucleosomal DNA was modelled by Monte Carlo means. An atomistic representation of DNA with a first\\u000a hydration shell was used. DNA single- and double-strand break (SSB and DSB) yields were calculated for 137Cs photons, x-rays and tritium beta-particles. Monte Carlo-generated electron tracks for liquid water were used to model energy\\u000a deposition. Chemical evolution of a track and

V. V. Moiseenko; R. N. Hamm; A. J. Waker; W. V. Prestwich

2001-01-01

360

Analysis of time-dependent radiation-induced conductivity in dielectrics and effect on cable SGEMP  

Microsoft Academic Search

Analytic and numerical solutions are presented for a simple time-dependent solid-state band model of radiation-induced conductivity in polyethelene and Teflon. The analytic solution is found to provide insight to physical processes dominant in various intervals of time throughout the radiation pulse. The numerical solution provides a representation for the dose-dependent proportionality factor F(..gamma..), proposed by van Lint et al, used

D. Lynn Shaeffer; Joel M. Siegel

1982-01-01

361

Radiation Induced Color Centers in TB3+-DOPED Phosphate Scintillation Glasses  

Microsoft Academic Search

Radiation induced optical absorption processes were studied at room temperature for a set of NaPO3-GdPO4 phosphate glasses doped by Tb3+ ions. Closely similar features were found under X-ray and gamma-ray irradiations, while under the intense 308 nm XeCl excimer laser irradiation these effects were further obscured by a possible surface damage. The induced absorption band at 3.3-3.4 eV was ascribed

M. Nikl; S. Baccaro; A. Cecilia; P. Fabeni; M. Martini; E. Mihokova; K. Nitsch; G. P. Pazzi; N. Solovieva; A. Vedda

2002-01-01

362

Predictive factors of radiation-induced skin toxicity in breast cancer patients  

PubMed Central

Background To assess the factors affecting the incidence of radiation-induced dermatitis in breast cancer patients treated with adjuvant 3 D conformal radiotherapy by the analysis of dosimetry and topical treatments. Methods Between September 2002 and July 2009, 158 breast cancer patients were treated with adjuvant 3 D conformal radiotherapy after undergoing surgery. Before November 2006, 90 patients were subjected to therapeutic skin care group and topical corticosteroid therapy was used for acute radiation dermatitis. Thereafter, 68 patients received prophylactic topical therapy from the beginning of radiotherapy. The two groups did not differ significantly in respect of clinical and treatment factors. Furthermore, the possible mechanisms responsible for the effects of topical treatment on radiation-induced dermatitis were investigated in vivo. Results The incidence of radiation-induced moist desquamation was 23% across 158 patients. Higher volume receiving 107% of prescribed dose within PTV (PTV-V107%; >28.6%) and volume receiving 110% of prescribed dose within treated volume (TV-V110%; > 5.13%), and no prophylactic topical therapy for irradiated skin, were associated with higher incidence of acute radiation dermatitis. The protective effect of prophylactic topical treatment was more pronounced in patients with TV-V110% > 5.13%. Furthermore, using irradiated mice, we demonstrated that topical steroid cream significantly attenuated irradiation-induced inflammation, causing a decrease in expression of inflammatory cytokines and TGF-beta 1. Conclusion TV-V110% > 5.13% may be an important predictor for radiation induced dermatitis. Prophylactic topical treatment for irradiated skin can significantly improve the tolerance of skin to adjuvant radiotherapy, especially for patients with higher TV-V110%.

2010-01-01

363

Differences in synchrotron radiation induced gas desorption from stainless steel and aluminium alloy  

Microsoft Academic Search

A comparative study has been made of the synchrotron-radiation-induced gas desorption from vacuum chambers made of stainless steel and aluminum alloy. The sample vacuum chambers of about 3.6 m length have been exposed to synchrotron radiation on an external photon beam line at the DCI storage ring in Orsay, France. The desorbed gas species are H2, CH4, CO, and CO2

M. Andritschky; Oswald Gröbner; A. G. Mathewson; P. Strubin; R. Souchet; B A Trickett

1989-01-01

364

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

NASA Astrophysics Data System (ADS)

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

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

2012-07-01

365

Control of radiation-induced diarrhea with cholestyramine. [Following pelvic or abdominal radiotherapy  

Microsoft Academic Search

Cholestyramine is a non-absorbable ion-exchange resin which specifically binds bile salts. We have treated seven patients with acute or chronic radiation-induced diarrhea that was refractory to the usual methods of control with cholestyramine. In each case, the diarrhea was controlled with cholestyramine. This observation supports previous experimental work with animals which indicated that bile salts contribute to the genesis of

R. S. Heusinkveld; M. R. Manning; S. A. Aristizabal

1978-01-01

366

In vitro evaluation of radiation-induced augmentation of the immune response.  

PubMed Central

Small doses (5--25 rads) of radiation augment the in vitro response of murine spleen cells to sheep red blood cells (SRBCs). Such augmentation appears to result from radiation-induced disruption of a homeostatic component of the response that exerts maximum effect soon after the introduction of antigen. Evidence is presented to support the concept that augmentation is due to injury of an exquisitely radiosensitive subpopulation of T cells with suppressor activity.

Anderson, R. E.; Lefkovits, I.

1979-01-01

367

Adenocarcinoma and colitis cystica profunda in a radiation-induced colonic stricture  

SciTech Connect

A case of adenocarcinoma of the rectum occurring 17 years after pelvic irradiation for squamous carcinoma of the cervix is reported. Earlier colonic resection had shown localized colitis cystica profunda in a radiation-induced colonic stricture. Colorectal cancer is an infrequent sequel to radiotherapy, which may occur many years after treatment of the primary tumor. Prolonged follow-up of these patients is essential.

Valiulis, A.P.; Gardiner, G.W.; Mahoney, L.J.

1985-02-01

368

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

Microsoft Academic Search

For identification of irradiated food, radiation-induced volatile hydrocarbons (HC) are determined by gas chromatography in the non-polar fraction of fat. However, in complex food matrices the detection is often disturbed by fat-associated compounds. On-line coupling of high performance liquid chromatography (LC) and gas chromatography (GC) is very efficient to remove such compounds from the HC fraction. The high sensitivity of

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

1995-01-01

369

Functionalization of polymer surfaces by radiation-induced grafting for separation of heavy metal ions  

NASA Astrophysics Data System (ADS)

The reported investigations were focused on the elucidation of the most important factors influencing radiation-induced grafting, particularly on studying the relationship between layer structure formed via copolymerization and content of monomers in the initial solution. Sorption capacity of the prepared by radiation grafting adsorber was evaluated by gamma radiometer using 152Eu3+ as a marker monitoring depletion of the radioisotope from the feed solution.

Kornacka, E. M.; Przybytniak, G.; Fuks, L.; Walo, M.; ?yczko, K.

2014-01-01

370

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

Microsoft Academic Search

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

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

2005-01-01

371

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

Microsoft Academic Search

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

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

2005-01-01

372

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

NASA Astrophysics Data System (ADS)

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

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

2005-04-01

373

Mucosal cytokine production in radiation-induced proctosigmoiditis compared with inflammatory bowel disease  

Microsoft Academic Search

OBJECTIVE:We measured the mucosal levels of interleukin 1? (IL-1?), IL-2, IL-6, and IL-8 in affected segments of radiation-induced proctosigmoiditis and compared these with the levels in normal controls and inflammatory bowel disease (IBD) patients.METHODS:Thirteen patients with histologically proven radiation proctosigmoiditis, 32 patients with active ulcerative colitis (UC), 35 patients with Crohn’s disease, and 15 normal subjects undergoing routine colonoscopy were

Anant V. K Indaram; Vernu Visvalingam; Mitch Locke; Simmy Bank

2000-01-01

374

Mucosal cytokine production in radiation-induced proctosigmoiditis compared with inflammatory bowel disease  

Microsoft Academic Search

OBJECTIVE:We measured the mucosal levels of interleukin 1? (IL-1?), IL-2, IL-6, and IL-8 in affected segments of radiation-induced proctosigmoiditis and compared these with the levels in normal controls and inflammatory bowel disease (IBD) patients.METHODS:Thirteen patients with histologically proven radiation proctosigmoiditis, 32 patients with active ulcerative colitis (UC), 35 patients with Crohn's disease, and 15 normal subjects undergoing routine colonoscopy were

Anant V. K. Indaram; Vernu Visvalingam; Mitch Locke; Simmy Bank

2000-01-01

375

Amelioration of Radiation-induced Hematological and Biochemical Alterations by Alstonia scholaris (a Medicinal Plant) Extract  

Microsoft Academic Search

The radioprotective efficacy of a hydro-alcoholic extracted material from the bark of Alstonia scholaris (ASE) was studied in mice against radiation-induced hematological and biochemical alterations. Swiss albino mice were administered ASE (100 mg\\/kg body weight\\/d for 5 consecutive day) orally prior to whole-body gamma irradiation (7.5 Gy). Radiation exposure resulted in a significant decline (P < .001) in erythrocytes and

Uma Gupta; Swafiya Jahan; Ranu Chaudhary; Pradeep Kumar Goyal

2008-01-01

376

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

Microsoft Academic Search

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

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

2010-01-01

377

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

NASA Technical Reports Server (NTRS)

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.

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

2000-01-01

378

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

SciTech Connect

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.

Mariz, T. [Instituto de Fisica, Universidade Federal de Alagoas, 57072-270, Maceio, Alagoas (Brazil)

2011-02-15

379

Implication of replicative stress-related stem cell ageing in radiation-induced murine leukaemia  

Microsoft Academic Search

Background:The essential aetiology of radiation-induced acute myeloid leukaemia (AML) in mice is the downregulation of the transcription factor PU.1. The causative mutation of the PU.1-endocing Sfpi1 gene consists mostly of C:G to T:A transitions at a CpG site and is likely to be of spontaneous origin. To work out a mechanism underlying the association between radiation exposure and the AML

N Ban; M Kai

2009-01-01

380

NADPH oxidase mediates radiation-induced oxidative stress in rat brain microvascular endothelial cells  

PubMed Central

The need to both understand and minimize the side effects of brain irradiation is heightened by the ever-increasing number of patients with brain metastases that require treatment with whole brain irradiation (WBI); some 200,000 cancer patients/year receive partial or WBI. At the present time, there are no successful treatments for radiation-induced brain injury, nor are there any known effective preventive strategies. Data support a role for chronic oxidative stress in radiation-induced late effects. However, the pathogenic mechanism(s) involved remains unknown. One candidate source of reactive oxygen species (ROS) is nicotinamide adenosine dinucleotide phosphate (NADPH) oxidase, which converts molecular oxygen (O2) to the superoxide anion (O2.?) upon activation. We hypothesize that brain irradiation leads to activation of NADPH oxidase. We report that irradiating rat brain microvascular endothelial cells in vitro leads to increased i] intracellular ROS generation, ii] activation of the transcription factor NF?B, iii] expression of ICAM-1 and PAI-1, and iv] expression of Nox4, p22phox, and p47phox. Pharmacologic and genetic inhibition of NADPH oxidase blocked the radiation-mediated upregulation of intracellular ROS, activation of NF?B, and upregulation of ICAM-1 and PAI-1. These results suggest that activation of NADPH oxidase may play a role in radiation-induced oxidative stress.

Collins-Underwood, J. Racquel; Zhao, Weiling; Sharpe, Jessica G.; Robbins, Mike E

2008-01-01

381

p53 Functions in Endothelial Cells to Prevent Radiation-Induced Myocardial Injury in Mice  

PubMed Central

p53 functions in the heart to promote myocardial injury after multiple types of stress. However, how p53 regulates radiation-induced myocardial injury, which develops after radiation therapy, is not well understood. Here, we utilize the Cre-loxP system to demonstrate that p53 functioned in endothelial cells to protect mice from myocardial injury after whole-heart irradiation. Mice with an endothelial cell-specific deletion of p53 succumbed to heart failure after whole-heart irradiation due to myocardial necrosis, systolic dysfunction and cardiac hypertrophy. Moreover, the onset of cardiac dysfunction was preceded by alterations in myocardial vascular permeability and density, which resulted in cardiac ischemia and myocardial hypoxia. Mechanistic studies using primary cardiac endothelial cells irradiated in vitro indicated that p53 signaling caused mitotic arrest and protected cardiac endothelial cells against radiation-induced mitotic catastrophe. Furthermore, mice lacking the cyclin-dependent kinase inhibitor p21, which is a transcriptional target of p53, were also sensitized to myocardial injury after wholeheart irradiation. Together, our results demonstrate that the p53/p21 axis functions to prevent radiation-induced myocardial injury in mice.

Lee, Chang-Lung; Moding, Everett J.; Cuneo, Kyle C.; Li, Yifan; Sullivan, Julie M.; Mao, Lan; Washington, Iman; Jeffords, Laura B.; Rodrigues, Rafaela C.; Ma, Yan; Das, Shiva; Kontos, Christopher D.; Kim, Yongbaek; Rockman, Howard A.; Kirsch, David G.

2012-01-01

382

Role of Ferulic Acid in the Amelioration of Ionizing Radiation Induced Inflammation: A Murine Model  

PubMed Central

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 ?-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 IKK?/? and I?B? and consequent nuclear translocation of nuclear factor kappa B (NF-?B). 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-?) 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.

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

2014-01-01

383

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

PubMed Central

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 Tukey’s 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.

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

2013-01-01

384

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

PubMed

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 ?-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 IKK?/? and I?B? and consequent nuclear translocation of nuclear factor kappa B (NF-?B). 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-?) 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

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

2014-01-01

385

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

SciTech Connect

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.

Flechsig, Paul [Department of Radiation Oncology, German Cancer Research Center and University Hospital Center Heidelberg, Heidelberg (Germany); Hartenstein, Bettina; Teurich, Sybille [Department of Signal Transduction, German Cancer Research Center, Heidelberg (Germany); Dadrich, Monika; Hauser, Kai; Abdollahi, Amir; Groene, Hermann-Josef [Department of Radiation Oncology, German Cancer Research Center and University Hospital Center Heidelberg, Heidelberg (Germany); Angel, Peter [Department of Signal Transduction, German Cancer Research Center, Heidelberg (Germany); Huber, Peter E., E-mail: p.huber@dkfz.d [Department of Molecular Pathology, German Cancer Research Center, Heidelberg (Germany)

2010-06-01

386

Quercetin liposomes protect against radiation-induced pulmonary injury in a murine model  

PubMed Central

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)-? and transforming growth factor (TGF)-?1 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-? and TGF-?1 concentrations and the HP content in the lung tissues. A histological examination revealed suppression of the inflammatory response and reduced TGF-?1 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.

LIU, HAO; XUE, JIAN-XING; LI, XING; AO, RUI; LU, YOU

2013-01-01

387

Hip2 ubiquitin-conjugating enzyme overcomes radiation-induced G2/M arrest.  

PubMed

Radiation induces cell cycle arrest and/or cell death in mammalian cells. In the present study, we show that Hip2, a ubiquitin-conjugating enzyme, can overcome radiation-induced G2/M cell cycle arrest and trigger the entry into mitosis. Ionizing radiation increased the levels of Hip2 by preventing its degradation but not its gene transcription. The stability of Hip2 in irradiated cells was further confirmed using live cell fluorescence imaging. Flow cytometric and molecular analyses revealed that Hip2 abrogated radiation-induced G2/M arrest, promoting entry into mitosis. Bimolecular fluorescence complementation assays and co-immunoprecipitation experiments showed that Hip2 interacted with and targeted p53 for degradation via the ubiquitin proteasome system, resulting in the activation of cdc2-cyclin B1 kinase to promote mitotic entry. These results contribute to our understanding of the mechanisms that regulate cell cycle progression and DNA damage-induced G2/M checkpoint cellular responses. PMID:23933584

Bae, Yoonhee; Jung, Song Hwa; Kim, Goo-Young; Rhim, Hyangshuk; Kang, Seongman

2013-12-01

388

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

SciTech Connect

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.

Peter, B.; Van Waarde, M.A.W.H.; Konings, A.W.T. [Univ. of Groningen (Netherlands); Vissink, A. [Univ. of Groningen (Netherlands)]|[Univ. Hospital, Groningen (Netherlands); `s-Gravenmade, E.J. [Univ. Hospital, Groningen (Netherlands)

1995-02-01

389

The efficacy of nardostachys jatamansi against the radiation induced haematological damage in rats.  

PubMed

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 Tukey's 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

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

2013-06-01

390

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

SciTech Connect

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.

Hackett, Micah J. [University of Michigan; Busby, Jeremy T [ORNL; Was, Gary [University of Michigan

2008-01-01

391

Radiation Induced Non-targeted Response: Mechanism and Potential Clinical Implications  

PubMed Central

Generations of students in radiation biology have been taught that heritable biological effects require direct damage to DNA. Radiation-induced non-targeted/bystander effects represent a paradigm shift in our understanding of the radiobiological effects of ionizing radiation in that extranuclear and extracellular effects may also contribute to the biological consequences of exposure to low doses of radiation. Although radiation induced bystander effects have been well documented in a variety of biological systems, including 3D human tissue samples and whole organisms, the mechanism is not known. There is recent evidence that the NF-?B-dependent gene expression of interleukin 8, interleukin 6, cyclooxygenase-2, tumor necrosis factor and interleukin 33 in directly irradiated cells produced the cytokines and prostaglandin E2 with autocrine/paracrine functions, which further activated signaling pathways and induced NF-?B-dependent gene expression in bystander cells. The observations that heritable DNA alterations can be propagated to cells many generations after radiation exposure and that bystander cells exhibit genomic instability in ways similar to directly hit cells indicate that the low dose radiation response is a complex interplay of various modulating factors. The potential implication of the non-targeted response in radiation induced secondary cancer is discussed. A better understanding of the mechanism of the non-targeted effects will be invaluable to assess its clinical relevance and ways in which the bystander phenomenon can be manipulated to increase therapeutic gain in radiotherapy.

Hei, Tom K.; Zhou, Hongning; Chai, Yunfei; Ponnaiya, Brian; Ivanov, Vladimir N.

2012-01-01

392

Hand Function in Children with an Upper Brachial Plexus Birth Injury: Results of the Nine-Hole Peg Test  

ERIC Educational Resources Information Center

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…

Immerman, Igor; Alfonso, Daniel T.; Ramos, Lorna E.; Grossman, Leslie A.; Alfonso, Israel; Ditaranto, Patricia; Grossman, John A. I.

2012-01-01

393

Constraint-Induced Movement Therapy for Children with Obstetric Brachial Plexus Palsy: Two Single-Case Series  

ERIC Educational Resources Information Center

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…

Buesch, Francisca Eugster

2010-01-01

394

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

PubMed Central

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.

Moens, N M; Caulkett, N A

2000-01-01

395

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

SciTech Connect

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.

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

2008-02-01

396

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

SciTech Connect

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.

Wan, X. Steven [Department of Radiation Oncology, University of Pennsylvania School of Medicine, Philadelphia, PA (United States); Ware, Jeffrey H. [Department of Radiation Oncology, University of Pennsylvania School of Medicine, Philadelphia, PA (United States); Zhou, Zhaozong [Department of Radiation Oncology, University of Pennsylvania School of Medicine, Philadelphia, PA (United States); Donahue, Jeremiah J. [Department of Radiation Oncology, University of Pennsylvania School of Medicine, Philadelphia, PA (United States); Guan, Jun [Department of Radiation Oncology, University of Pennsylvania School of Medicine, Philadelphia, PA (United States); Kennedy, Ann R. [Department of Radiation Oncology, University of Pennsylvania School of Medicine, Philadelphia, PA (United States)]. E-mail: akennedy@mail.med.upenn.edu

2006-04-01

397

[Analysis of brachial plexus injuries reported to MRM].  

PubMed

Upper-arm weakness (paresis) or paralysis in the newborn (Erb's palsy) usually indicates peripheral-nerve damage to the brachial plexus. Its location lateral to the lower cervical spine (C5-T1) renders it susceptible to injury by pressure or traction during pregnancy, labor or delivery. The Medical Risk Management (MRM), a "Madanes" group company, routinely receives adverse events reports from medical centers covered by its medical malpractice insurance. In the current study, the authors analyzed 536 reports of Erb's palsy in the newborn, with varying degrees of severity, which were reported to MRM during the years 1993-2004. A dedicated questionnaire with approximately 30 relevant variables was formed in order to analyze these reports. Reference values for pregnancies and deliveries in the general population were obtained from the Israeli Central Statistics Bureau, Information Department in the Ministry of Health, the Israeli Society of Maternal-Fetal Medicine, as well as relevant data in the medical literature. It was found that during the analyzed period of time, the reporting rate for Erb's palsy varied between 0.5-1.2 cases per 1,000 newborns. Compared with the general Israeli population, women in the study group were older, overweight, with higher parity and have diabetic traits. The authors noted a systematic error of underestimation of fetal weight, compared to the actual birth weight in our study group. Although, the majority of the Erb cases followed vaginal deliveries at term, 3% of the cases followed Cesarean sections, the majority of which were either elective or in early labor. A quarter of the Erb cases followed instrument delivery, while the rate of instrumental deliveries in the general population averaged only 5% throughout the study period. In half of the Erb cases, difficulty in extraction of the shoulder (shoulder dystocia) of the involved arm was found in the delivery medical record, but reference to shoulder or head extraction was noted in only half of the cases following vaginal deliveries. However, the rate of medical records with adequate reference to shoulder or head extraction increased from 44% in the beginning, to 74% at the end of the analyzed study period. The average birth weight of our study group was 3888+569 grams, which is significantly higher than the average birth weight in the general population. It was also noted that birth weights of Erb cases are of higher percentiles on the Israeli nomogram of gestational age adjusted birth weights. Thus, 53% of the newborns in our study group were above the 90th percentile and 31% above the 97th percentile of the general population nomogram. Various risk factors for brachial plexus injury were found in this large sample of Erb's palsy cases in Israel. However, the relative importance of each of these factors cannot be determined due to lack of an appropriate control group and valid reference data for the general population of pregnancies and deliveries during the analyzed study period. Nonetheless, the dedicated questionnaire, which was developed for this analysis, may assist in compiling real-time data to support the findings of this study. PMID:20549920

Sherman, Dan; Halamish-Shani, Talia; Gershtansky, Yael; Tal, Yosi; Feingold, Michael

2010-02-01

398

Relationship Between Brachial Flow - Mediated Dilation and Carotid Intima- Media Thickness in an Elderly Cohort: The Cardiovascular Health Study  

PubMed Central

Objective The aim of this study was to determine the relationship between brachial flow-mediated dilation (FMD) and carotid intima-media thickness (IMT) in a large multi-ethnic elderly cohort. Background Brachial flow-mediated dilation (FMD) is a physiologic measure and Carotid IMT is an anatomic structural measure of subclinical atherosclerosis. Both brachial FMD and carotid IMT have been associated with cardiovascular risk factors and cardiovascular events. The relationship between brachial FMD and carotid IMT is less clear especially in older adults. Methods Brachial FMD, carotid IMT and traditional cardiovascular risk factors were measured in 2338 adults, age 72–98 years who were participants in the Cardiovascular Health Study. The relationship between FMD and IMT was assessed both unadjusted and also after adjusting for age, gender, race/ethnicity. BMI, HDL, LDL, systolic and diastolic blood pressure, serum creatinine, current smoking, diabetes mellitus, hormone therapy and prior CVD. Results Both brachial FMD and carotid IMT correlated significantly with age, HDL levels, waist/hip ratio, serum cholesterol and number of CV risk factors. Brachial FMD was not associated with CCA IMT in this elderly cohort (Pearson partial correlation coefficient= ?0.0252, p=0.222). In the adjusted linear regression model with CCA IMT as the dependent variable, brachial FMD was also not associated with CCA IMT (beta coefficient= ?0.006, p=0.470) Conclusion Brachial FMD and CCA IMT are not related in population-based older adults. Brachial FMD and CCA IMT may be distinct and independent stages in the complex atherosclerotic process.

Yeboah, Joseph; Burke, Gregory L; Crouse, John R; Herrington, David M

2009-01-01

399

Improved Protection Against Solar-Simulated Radiation-Induced Immunosuppression by a Sunscreen with Enhanced Ultraviolet A Protection  

Microsoft Academic Search

Ultraviolet radiation-induced immunosuppression is thought to play a part in skin cancer. Several studies have indicated that sunscreens that are designed to protect against erythema failed to give comparable protection against ultraviolet radiation-induced immunosuppression. One possible reason for this discrepancy is inadequate ultraviolet A protection. This study evaluated the level of immunoprotection in mice afforded by two broad-spectrum sunscreens with

Amy Fourtanier; Audrey Gueniche; Delphine Compan; Susan L. Walker; Antony R. Young

2000-01-01

400

A novel preparation of surface-modified paramagnetic magnetite\\/polystyrene nanocomposite microspheres by radiation-induced miniemulsion polymerization  

Microsoft Academic Search

A novel and facile approach to the preparation of paramagnetic magnetite\\/polystyrene nanocomposite microspheres by 60Co ?-ray radiation-induced miniemulsion polymerization is reported. First, we modified the magnetite nanoparticles (MPs) with a Y-shaped surfactant: 12-hexanoyloxy-9-octadecenoic acid (HOA). Nanocomposite microspheres consisting of polystyrene–iron oxide nanoparticles then were prepared by the radiation-induced miniemulsion polymerization of styrene in the presence of HOA-modified MPs using HOA

Zhen Qian; Zhicheng Zhang; Yun Chen

2008-01-01

401

Traumatic vertebral artery dissection in an adult with brachial plexus injury and cervical spinal fractures  

PubMed Central

We present a case of a 32 year-old right-hand dominant woman who sustained a right brachial plexus injury, ipsilateral fractures of the cervical spine transverse processes, and vertebral artery dissection. She presented to us four days following the initiating accident. Magnetic Resonance Imaging showed normal brachial plexus along with vertebral artery dissection with intramural thrombus and vascular lumen occlusion. The dissection was managed conservatively. A repeat CAT-SCAN Angiography three months later showed healing of the dissection plus vascular lumen re-canalization. There were no sequelae due to the dissection. The details of the case are discussed in this report.

2007-01-01

402

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

PubMed Central

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.

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

2014-01-01

403

Severe brachial plexus injury after retropubic radical prostatectomy -A case report-  

PubMed Central

A 69-year-old man with prostate cancer underwent surgery for 16 h. Approximately 6 h after surgery, the patient developed severe pain and motor weakness in his right arm. After neurologic examinations that included a nerve conduction study and electromyography, the patient was diagnosed with a brachial plexus injury. The causes of the brachial plexus injury were thought to be abduction of both arms, direct compression of the shoulder brace, and prolonged surgery. Most of the postoperative peripheral nerve injuries due to patient position are preventable, and anesthetists and surgeons should be very careful in positioning the patient accurately.

2012-01-01

404

Low estimated glomerular filtration rate is a major determinant of low ankle-brachial index and toe-brachial index in type 2 diabetes.  

PubMed

We enrolled 1461 Taiwanese type 2 diabetic outpatients with ankle-brachial index (ABI) and toe-brachial index (TBI) examinations, excluding participants with history of stroke, end-stage renal disease, malignancy, acute myocardial infarction, amputation, and overt calcification of the lower limbs (ABI > 1.3). Ankle-brachial index values <0.9 were found in 2.8% of the patients and 5.7% had TBI < 0.6. Estimated glomerular filtration rate (eGFR; 90 ± 33 mL/min per 1.73 m2) obtained from 473 patients correlated significantly with both ABI and TBI. Progressive eGFR decline was observed in 419 participants with normal ABI and TBI, 35 with normal ABI but low TBI, and 19 with low ABI and normal or low TBI (P for trend < .001). After adjusting for confounding factors, age and eGFR were significantly associated with TBI and ABI. Low eGFR is associated with peripheral arterial disease in type 2 diabetes with mild to moderate renal insufficiency. PMID:21642287

Sheen, Yi-Jing; Lin, Jainn-Liang; Lee, I-Te; Hsu, Yuan-Nian; Li, Tsai-Chung; Sheu, Wayne Huey-Herng

2012-01-01

405

Radiation induced bystander effect by GAP junction channels in human fibroblast cell  

NASA Astrophysics Data System (ADS)

The chemical factor involved in bystander effect and its transfer pathway were investigated in a confluent human fibroblast cell (AG1522) population. Micronuclei (MN) and G1-phase arrest were detected in cells irradiated by carbon (~100 keV/?m) ions at HIMAC. A very low dose irradiation showed a high effectiveness in producing MN, suggesting a bystander effect. This effectiveness was enhanced by 8-Br-cAMP treatment that increases gap junctional intercellular communication (GJIC). On the other hand, the effect was reduced by 5% DMSO treatment, which reduce the reactive oxygen species (ROS), and suppressed by 100 ?M lindane treatment, an inhibitor of GJIC. In addition, the radiation-induced G1-phase arrest was also enhanced by cAMP, and reduced or suppressed by DMSO or lindane. A microbeam device (JAERI) was also used for these studies. It was found that exposing one single cell in a confluent cell population to exactly one argon (~1260 keV/?m) or neon (~430 keV/ ?m) ion, additional MN could be detected in many other unirradiated cells. The yield of MN increased with the number of irradiated cells. However, there was no significant difference in the MN induction when the cells were irradiated by increasing number of particles. MN induction by bystander effect was partly reduced by DMSO, and effectively suppressed by lindane. Our results obtained from both random irradiation and precise numbered irradiation indicate that both GJIC and ROS contributed to the radiation-induced bystander effect, but the cell gap junction channels likely play an essential role in the release and transfer of radiation-induced chemical factors.

Furusawa, Y.; Shao, C.; Aoki, M.; Kobayashi, Y.; Funayama, T.; Ando, K.

406

Stem cell therapies for the treatment of radiation-induced normal tissue side effects.  

PubMed

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

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

2014-07-10

407

Late treatment with imatinib mesylate ameliorates radiation-induced lung fibrosis in a mouse model  

PubMed Central

Background We have previously shown that small molecule PDGF receptor tyrosine kinase inhibitors (RTKI) can drastically attenuate radiation-induced pulmonary fibrosis if the drug administration starts at the time of radiation during acute inflammation with present but limited effects against acute inflammation. To rule out interactions of the drug with acute inflammation, we investigated here in an interventive trial if a later drug administration start at a time when the acute inflammation has subsided - has also beneficial antifibrotic effects. Methods Whole thoraces of C57BL/6 mice were irradiated with 20 Gy and treated with the RTKI imatinib starting either 3 days after radiation (during acute inflammation) or two weeks after radiation (after the acute inflammation has subsided as demonstrated by leucocyte count). Lungs were monitored and analyzed by clinical, histological and in vivo non-invasive computed tomography as a quantitative measure for lung density and lung fibrosis. Results Irradiation induced severe lung fibrosis resulting in markedly reduced mouse survival vs. non-irradiated controls. Both early start of imatinib treatment during inflammation and late imatinib start markedly attenuated the development of pulmonary fibrosis as demonstrated by clinical, histological and qualitative and quantitative computed tomography results such as reduced lung density. Both administration schedules resulted in prolonged lifespans. The earlier drug treatment start resulted in slightly stronger beneficial antifibrotic effects along all measured endpoints than the later start. Conclusions Our findings show that imatinib, even when administered after the acute inflammation has subsided, attenuates radiation-induced lung fibrosis in mice. Our data also indicate that the fibrotic fate is not only determined by the early inflammatory events but rather a complex process in which secondary events at later time points are important. Because of the clinical availability of imatinib or similar compounds, a meaningful attenuation of radiation-induced lung fibrosis in patients seems possible.

2009-01-01

408

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

SciTech Connect

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.

Jin, Ho-Seon.

1992-01-01

409

Effects of Berberine Against Radiation-Induced Intestinal Injury in Mice  

SciTech Connect

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.

Li Guanghui [Institute for Cancer Research in People's Liberation Army, Xinqiao Hospital, Third Military Medical University, Chongqing (China); Zhang Yaping [Institute of Burn Research, Southwest Hospital, Third Military Medical University, Chongqing (China); Tang Jinliang [Department of Pathology, Xinqiao Hospital, Third Military Medical University, Chongqing (China); Chen Zhengtang; Hu Yide [Institute for Cancer Research in People's Liberation Army, Xinqiao Hospital, Third Military Medical University, Chongqing (China); Wei Hong [Department of Plastic Surgery, Southwest Hospital, Third Military Medical University, Chongqing (China); Li Dezhi; Hao Ping [Institute for Cancer Research in People's Liberation Army, Xinqiao Hospital, Third Military Medical University, Chongqing (China); Wang Donglin, E-mail: wdl_tmmu@yahoo.c [Institute for Cancer Research in People's Liberation Army, Xinqiao Hospital, Third Military Medical University, Chongqing (China)

2010-08-01

410

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

PubMed

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

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

411

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

SciTech Connect

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.

Lee, Jin Hyup [School of Life Sciences and Biotechnology, College of Natural Sciences, Kyungpook National University, Taegu 702-701 (Korea, Republic of); Lee, You Mie [School of Life Sciences and Biotechnology, College of Natural Sciences, Kyungpook National University, Taegu 702-701 (Korea, Republic of); Park, Jeen-Woo [School of Life Sciences and Biotechnology, College of Natural Sciences, Kyungpook National University, Taegu 702-701 (Korea, Republic of)]. E-mail: parkjw@knu.ac.kr

2005-08-26

412

Beta-lapachone suppresses radiation-induced activation of nuclear factor-kappaB.  

PubMed

Anticancer effects of beta-lapachone (beta-lap) are due to generation of ROS and metabolic catastrophes as a result of NAD(P)H:quinone oxidoreductase (NQO1)-mediated futile cycling between the oxidized and reduced forms of beta-lap. It has been shown that NQO1 is also essential for the TNF-induced activation of NF-kappaB and that beta-lap suppresses the TNF-induced NF-kappaB activation. We investigated whether or not NQO1 is involved and beta-lap suppresses the radiation-induced NF-kappaB activation using A549 human lung cancer cells and NQO1-knock down A549 cells (shNQO1 A549 cells). Irradiation with 4 Gy markedly increased the DNA binding activity of NF-kappaB in A549 cells, but not in the shNQO1 A549 cells, thus demonstrating that NQO1 plays a pivotal role in irradiation-induced NF-kappaB activation. Treatment with 10 micronM beta-lap for 4 h almost completely abrogated the radiation-induced increase in NF-kappaB activation and the transcription of NF-kappaB target genes such as bcl2, gadd45beta and cyclinD1. Moreover, beta-lap markedly suppressed the activation of IkappaB kinase gamma (IKKgamma) and the subsequent phosphorylation of IkappaBalpha, thereby inhibiting NF-kappaB activation. It is concluded that beta-lap suppresses the radiation-induced activation of NF-kappaB by interrupting the involvement of NQO1 in the activation of NF-kappaB, thereby inhibiting the transcription of survival signals. The radiosensitization caused by beta-lap may, in part, be attributed to beta-lap-induced suppression of NF-kappaB activation. PMID:20200474

Dong, Guang Zhi; Oh, Eun Taex; Lee, Hyemi; Park, Moon Taek; Song, Chang Won; Park, Heon Joo

2010-05-31

413

Radiation-Induced Reduction of Ceria in Single and Polycrystalline Thin Films  

SciTech Connect

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.

Kumar, Amit; Devanathan, Ramaswami; Shutthanandan, V.; Kuchibhatla, Satyanarayana V N T; Karakoti, Ajay S.; Yang, Yong; Thevuthasan, Suntharampillai; Seal, Sudipta

2012-01-12

414

Photo and radiation-induced preparation of nanocrystalline copper and cuprous oxide catalysts  

Microsoft Academic Search

Spherical copper nanoparticles have been prepared by photo- or radiation-induced reduction of aqueous solutions containing\\u000a 10?3 mol.dm?3 copper sulphate or formate, 1.3 mol.dm?3 propan-2-ol and polyvinyl alcohol as a stabilizer. Increase of initial copper concentration to 10?2 mol.dm?3 resulted in formation of different reaction product—octahedral cuprous oxide nanoparticles. Solutions were irradiated by\\u000a means of electron beam, 60Co ? rays (dose rate

Jan Bárta; Milan Pospíšil; Václav ?uba

2010-01-01

415

[New results on the linearity of the dose-response relationship of radiation-induced mutation].  

PubMed

Mutations induced by ionizing radiation in germ cells may affect future generations; mutations induced in somatic cells may damage the irradiated persons themselves, because radiation carcinogenesis is assumed to result from genetic damage induced in somatic cells. Since we are exposed mainly to low doses of ionizing radiation, both from natural and artificial sources, especially the dose dependence of radiation-induced mutations in the low-dose range is of interest. A review of recent studies on the induction of mutations by X-rays in human cells (in vitro) favors the hypothesis that in the low-dose range the dose dependence is linear, without a "threshold." PMID:3065646

Traut, H

1988-08-01

416

Simple method to demonstrate radiation-inducible radiation resistance in microbial cells.  

PubMed Central

A simple method for detection of radiation-inducible radiation resistance was developed by irradiating aliquots (0.01 ml) of cell suspension on agar plates. Part of each experimental plate was subjected to an induction treatment, and subsequent radiation resistance was compared with that of untreated cells on the same plate. The UV radiation resistance of a Micrococcus sp. was increased approximately 1.6 times by an induction treatment. This simple procedure of irradiating cells in a "fixed" position on agar avoided washing, centrifugation, and cell enumeration required in traditional methods. Images

Tan, S T; Maxcy, R B

1986-01-01

417

Radiation-induced decomposition of the tributyl phosphate-nitric acid system: Role of nitric acid  

Microsoft Academic Search

Radiation-induced decomposition of tributyl phosphate-nitric acid as a two-component system has been studied. Degradation products, dibutylphosphoric acid (DBP) and monobutylphosphoric acid (MBP), were determined by separation-extraction method. 0.59, 0.78 and 1.38 are the G (DBP) values and 0.15, 0.17 and 0.13 are the G (MBP) values obtained for pure TBP, TBP-3M HNO3 extract and TBP-5M HNO3 extract, respectively. G (–HNO3)

M. V. Krishnamurthy; R. Sampathkumar

1992-01-01

418

Risedronate Prevents Early Radiation-Induced Osteoporosis in Mice at Multiple Skeletal Locations  

PubMed Central

Introduction Irradiation of normal, non-malignant bone during cancer therapy can lead to atrophy and increased risk of fracture at several skeletal sites, particularly the hip. This bone loss has been largely attributed to damaged osteoblasts. Little attention has been given to increased bone resorption as a contributor to radiation-induced osteoporosis. Our aims were to identify if radiation increases bone resorption resulting in acute bone loss, and if bone loss could be prevented by administering risedronate. Methods Twenty-week old female C57BL/6 mice were either: not irradiated and treated with placebo (NR+PL); whole-body irradiated with 2 Gy X-rays and treated with placebo (IR+PL); or irradiated and treated with risedronate (IR+RIS; 30?g/kg every other day). Calcein injections were administered 7 and 2 days before sacrifice. Bones were collected 1, 2, and 3 weeks after exposure. MicroCT analysis was performed at 3 sites: proximal tibial metaphysis; distal femoral metaphysis; and the body of the 5th lumbar vertebra (L5). Osteoclasts were identified from TRAP-stained histological sections. Dynamic histomorphometry of cortical and trabecular bone was performed. Circulating TRAP5b and osteocalcin concentrations were quantified. Results In animals receiving IR+PL, significant (P < 0.05) reduction in trabecular volume fraction relative to non-irradiated controls was observed at all three skeletal sites and time points. Likewise, radiation-induced loss of connectivity and trabecular number relative to NR+PL were observed at all skeletal sites throughout the study. Bone loss primarily occurred during the first week post-exposure. Trabecular and endocortical bone formation was not reduced until Week 2. Loss of bone volume was absent in animals receiving IR+RIS. Histology indicated greater osteoclast numbers at Week 1 within IR+PL mice. Serum TRAP5b concentration was increased in IR+PL mice only at Week 1 compared to NR+PL (P = 0.05). Risedronate treatment prevented the radiation-induced increase in osteoclast number, surface, and TRAP5b. Conclusion This study demonstrated a rapid loss of trabecular bone at several skeletal sites after whole-body irradiation. Changes were accompanied by an increase in osteoclast number and serum markers of bone loss. Risedronate entirely prevented bone loss, providing further evidence that an increase in bone resorption likely caused this radiation-induced bone loss.

Willey, Jeffrey S.; Livingston, Eric W.; Robbins, Michael E.; Bourland, J. Daniel; Tirado-Lee, Leidamarie; Smith-Sielicki, Hope; Bateman, Ted A.

2009-01-01

419

Radiation-induced photoconductivity in polymers: Poly(vinylidene fluoride) compared with polyethylene terephthalate  

SciTech Connect

Transient and dc photoconductivity measurements are presented for two low-mobility dielectrics, poly (vinylidene fluoride) and polyethylene terephthalate. In each case, the data are analyzed using the present models for dispersive transport, and the inadequacies of these theories when applied to these low-mobility dielectrics are illustrated. In this paper we report an anomalously small transient photoresponse in poly (vinylidene fluoride); from our analysis, we attribute this result to the dispersive transport limited drift mobility in this material. Polymer structure and electric field contributions to the radiation-induced conductivity in these dielectrics are also discussed.

Kurtz, S.R.; Hughes, R.C.

1983-01-01

420

Radiation induced failures of complementary metal oxide semiconductor containing pacemakers: a potentially lethal complication  

SciTech Connect

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.

Lewin, A.A.; Serago, C.F.; Schwade, J.G.; Abitbol, A.A.; Margolis, S.C.

1984-10-01

421

Role of sphingolipids in murine radiation-induced lung injury: protection by sphingosine 1-phosphate analogs  

PubMed Central

Clinically significant radiation-induced lung injury (RILI) is a common toxicity in patients administered thoracic radiotherapy. Although the molecular etiology is poorly understood, we previously characterized a murine model of RILI in which alterations in lung barrier integrity surfaced as a potentially important pathobiological event and genome-wide lung gene mRNA levels identified dysregulation of sphingolipid metabolic pathway genes. We hypothesized that sphingolipid signaling components serve as modulators and novel therapeutic targets of RILI. Sphingolipid involvement in murine RILI was confirmed by radiation-induced increases in lung expression of sphingosine kinase (SphK) isoforms 1 and 2 and increases in the ratio of ceramide to sphingosine 1-phosphate (S1P) and dihydro-S1P (DHS1P) levels in plasma, bronchoalveolar lavage fluid, and lung tissue. Mice with a targeted deletion of SphK1 (SphK1?/?) or with reduced expression of S1P receptors (S1PR1+/?, S1PR2?/?, and S1PR3?/?) exhibited marked RILI susceptibility. Finally, studies of 3 potent vascular barrier-protective S1P analogs, FTY720, (S)-FTY720-phosphonate (fTyS), and SEW-2871, identified significant RILI attenuation and radiation-induced gene dysregulation by the phosphonate analog, fTyS (0.1 and 1 mg/kg i.p., 2×/wk) and to a lesser degree by SEW-2871 (1 mg/kg i.p., 2×/wk), compared with those in controls. These results support the targeting of S1P signaling as a novel therapeutic strategy in RILI.—Mathew, B., Jacobson, J. R., Berdyshev, E., Huang, Y., Sun, X., Zhao, Y., Gerhold, L. M., Siegler, J., Evenoski, C., Wang, T., Zhou, T., Zaidi, R., Moreno-Vinasco, L., Bittman, R., Chen, C. T., LaRiviere, P. J., Sammani, S., Lussier, Y. A., Dudek, S. M., Natarajan, V., Weichselbaum, R. R., Garcia, J. G. N. Role of sphingolipids in murine radiation-induced lung injury: protection by sphingosine 1-phosphate analogs.

Mathew, Biji; Jacobson, Jeffrey R.; Berdyshev, Evgeny; Huang, Yong; Sun, Xiaoguang; Zhao, Yutong; Gerhold, Lynnette M.; Siegler, Jessica; Evenoski, Carrie; Wang, Ting; Zhou, Tong; Zaidi, Rafe; Moreno-Vinasco, Liliana; Bittman, Robert; Chen, Chin Tu; LaRiviere, Patrick J.; Sammani, Saad; Lussier, Yves A.; Dudek, Steven M.; Natarajan, Viswanathan; Weichselbaum, Ralph R.; Garcia, Joe G. N.

2011-01-01

422

Protective effects of L-selenomethionine on space radiation induced changes in gene expression.  

PubMed

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

Stewart, J; Ko, Y-H; Kennedy, A R

2007-06-01

423

Radiation-induced electron paramagnetic resonance signal and soybean isoflavones content  

NASA Astrophysics Data System (ADS)

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.

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

2012-09-01

424

A review on radiation-induced nucleation and growth of colloidal metallic nanoparticles  

PubMed Central

This review presents an introduction to the synthesis of metallic nanoparticles by radiation-induced method, especially gamma irradiation. This method offers some benefits over the conventional methods because it provides fully reduced and highly pure nanoparticles free from by-products or chemical reducing agents, and is capable of controlling the particle size and structure. The nucleation and growth mechanism of metallic nanoparticles are also discussed. The competition between nucleation and growth process in the formation of nanoparticles can determine the size of nanoparticles which is influenced by certain parameters such as the choice of solvents and stabilizer, the precursor to stabilizer ratio, pH during synthesis, and absorbed dose.

2013-01-01

425

A mechanistic model for radiation-induced crystallization and amorphization in U 3Si  

NASA Astrophysics Data System (ADS)

Of concern for the proposed Advanced Neutron Source and Research Reactors, which would use intermetallic fuels, are potential radiation-induced phenomena that could affect the physical and mechanical properties of intermetallic aluminum dispersion fuels. For this reason and because of observations of radiation-induced amorphization of U 3Si during ion irradiation, the phenomenology of radiation-induced amorphization is assessed. A rate theory model is formulated wherein amorphous clusters are formed by the damage event. These clusters are considered centers of expansion (CE), or excess-free-volume zones. Simultaneously, centers of compression (CC) are created in the material. In general, many more CCs are created per ion than CEs. The CCs are local regions of increased density that travel through the material as an elastic (e.g., acoustic) shock wave. The CEs can be annihilated upon contact with a sufficient number of CCs, forming either a crystallized region indistinguishable from the host material, or a region with a slight disorientation (recrystallized grain). Recrystallized grains grow by the accumulation of additional CCs. Full amorphization is calculated on the basis of achieving a volume fraction consistent with the close packing of spherical entities. Amorphization of a recrystallized grain is hindered by the presence of the grain boundary. Preirradiation of U 3Si above the critical temperature for amorphization results in the observed formation of nanometer-size grains. In addition, the subsequent reirradiation of these samples in the same ion flux at temperatures below the critical temperatures shows that the material has developed a resistance to radiation-induced amorphization (i.e., a higher dose is needed to amorphize the preirradiated samples than for those that have not been preirradiated). In the model, it is assumed that grain boundaries act as effective defect sinks, and that enhanced defect annihilation is responsible for retarding amorphization below the critical temperature. The calculations have been validated against data from ion-irradiation experiments with U 3Si. The model has also been applied to the ion-induced motion of the interface between crystalline and amorphous phases of U 3Si. The results of this analysis are compared to data and results of calculations for ion bombardment of Si.

Rest, J.

1995-08-01

426

Simple method to demonstrate radiation-inducible radiation resistance in microbial cells  

SciTech Connect

A simple method for detection of radiation-inducible radiation resistance was developed by irradiating aliquots (0.01 ml) of cell suspension on agar plates. Part of each experimental plate was subjected to an induction treatment, and subsequent radiation resistance was compared with that of untreated cells on the same plate. The UV radiation resistance of a Micrococcus sp. was increased approximately 1.6 times by an induction treatment. This simple procedure of irradiating cells in a fixed position on agar avoided washing, centrifugation, and cell enumeration required in traditional methods.

Tan, S.T.; Maxcy, R.B.

1986-01-01

427

The influence of infrared radiation on short-term ultraviolet-radiation-induced injuries  

SciTech Connect

Because heat has been reported to influence adversely short- and long-term ultraviolet (UV)-radiation-induced skin damage in animals, we investigated the short-term effects of infrared radiation on sunburn and on phototoxic reactions to topical methoxsalen and anthracene in human volunteers. Prior heating of the skin caused suppression of the phototoxic response to methoxsalen as evidenced by an increase in the threshold erythema dose. Heat administered either before or after exposure to UV radiation had no detectable influence on sunburn erythema or on phototoxic reactions provoked by anthracene.

Kaidbey, K.H.; Witkowski, T.A.; Kligman, A.M.

1982-05-01

428

Effect of G/M ratio on the radiation-induced degradation of sodium alginate  

NASA Astrophysics Data System (ADS)

Radiation-induced degradation of sodium alginate (NaAlg) having different G/M ratios was investigated. NaAlg samples were irradiated with gamma rays in air at ambient temperature in the solid state at low dose rate. Change in their molecular weights was followed by size exclusion chromatography (SEC). Changes in their rheological properties and viscosity values as a function of temperature, shear rate and irradiation dose were also determined. Chain scission yields, G( S), and degradation rates were calculated. It was observed that G/M ratio was an important factor controlling the G( S) and degradation rate of sodium alginate.

?en, Murat; Rendevski, Stojan; Kavakl?, P?nar Akka?; Sepehrianazar, Amir

2010-03-01

429

Semi-interpenetrating polymer networks of poly(3-hydroxybutyrate) prepared by radiation-induced polymerization  

NASA Astrophysics Data System (ADS)

Semi-interpenetrating polymer networks (IPNs) based on bacterial poly(3-hydroxy butyrate) with a hydrophilic monomer at different compositions were prepared by radiation-induced polymerization using ?-rays from a 60Co source with a total dose of 10-100 kGy. The swelling behaviour was determined by water content at equilibrium, while thermal properties and crystallinity were studied by differential scanning calorimetry. Extraction of the soluble part of PHB from the films at low and high temperature with water or chloroform as well as FTIR data indicate the occurrence of the crosslinking reaction in the hydrogels. The results show a water uptake increasing with the hydrophilic component until 25%.

Martellini, Flavia; Innocentini Mei, Lúcia H.; Lora, Silvano; Carenza, Mario

2004-09-01

430

Influence of the primary recoil spectrum on radiation-induced segregation in nickel-silicon  

SciTech Connect

Radiation induced segregation in Ni-12.7% Si has been examined for 1.5 MeV He, 2.0 MeV Li, and 2.75 MeV Kr irradiations. A method to simultaneously damage and analyze the specimens during light-ion irradiation is described. The amount of segregation was determined by using Rutherford backscattering spectrometry to measure the thickness of the ..gamma..' layer which develops at the surface. Substantially less segregation of Si to the surface is observed for the Kr irradiation than for the light-ion irradiations at 520/sup 0/C.

Averback, R.S.; Rehn, L.E.; Wiedersich, H.; Cook, R.E.

1980-01-01

431