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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 Central

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

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

5

[Acute fulminant brachial plexopathy with good recovery: electrophysiological features].  

PubMed

We report a case of fulminant brachial plexopathy with radicular involvement. A 25-year-old man developed acute total monoplegia in the left upper limb. Needle electromyography showed extensive acute denervation in the C5-T1 spinal segments, and peripheral sensory nerve conduction was normal, mimicking a pre-ganglionic lesion. However, left median somatosensory evoked potentials revealed abnormal Erb's point potential, suggesting a brachial plexus lesion. Corticosteroid treatment resulted in good recovery. These findings suggest that the primary pathophysiology was conduction block and this can explain the good clinical recovery in this patient. PMID:22790808

Hemmi, Shoji; Kurokawa, Katsumi; Nagai, Taiji; Izawa, Nana; Murakami, Tatsufumi; Sunada, Yoshihide

2012-01-01

6

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

7

Lightning strike-induced brachial plexopathy.  

PubMed

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

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

2014-10-01

8

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. PMID:24772163

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

2014-01-01

9

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

PubMed

A brachial plexus lesion is not common in hereditary neuropathy with liability to pressure palsy (HNPP). We report the clinical and electrodiagnostic features of young soldiers with HNPP presenting with brachial plexopathy. By reviewing 2year medical records from Korean military hospitals, we identified soldiers with brachial plexus lesions. Among them, patients diagnosed with HNPP were determined and clinical and electrophysiological findings were compared between HNPP and non-HNPP patients with a brachial plexus lesion. Thirteen patients (6.8%) were diagnosed with HNPP among 189 patients with a brachial plexus lesion. Push-ups, as either a punishment or an exercise, was the most frequent preceding event in HNPP patients (76.9%), whereas it was rare in non-HNPP patients. The distal motor latency of the median nerve showed the highest sensitivity (90.9%) and specificity (100%) for HNPP in patients with a brachial plexus lesion. In conclusion, HNPP should be suspected in patients with brachial plexopathy if brachial plexopathy develops after push-ups or if the distal motor latency of median nerves is prolonged. PMID:25175852

Kim, Kyoung-Eun

2014-11-15

10

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

PubMed Central

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

Shahien, Radi; Bowirrat, Abdalla

2011-01-01

11

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

12

Lumbosacral plexus delineation, dose distribution, and its correlation with radiation-induced lumbosacral plexopathy in cervical cancer patients  

PubMed Central

Background To evaluate the dose distribution to the lumbosacral plexus (LSP) and its correlation with radiation-induced lumbosacral plexopathy (RILSP) in patients with cervical cancer treated with intensity-modulated radiotherapy (IMRT) and high-dose-rate brachytherapy. Materials and methods After meeting eligibility criteria, 50 patients with cervical cancer were selected who were treated with IMRT and high-dose-rate brachytherapy, and the LSP was contoured. Mean volume; percentages of LSP volume absorbing 40, 50, 55, and 60 Gy (V30, V40, V50, V55, and V60) and point doses (P1, P2, P3, P4, P5, P6, P7, P8, P9, and P10); and RILSP incidence were calculated. Results At 60 months of follow-up, four patients (8%) were found to have grade 2/3 RILSP. The mean maximal LSP dose in patients with RILSP was 59.6 Gy compared with 53.9 Gy in patients without RILSP (control; P=0.04). The mean values of V40, V50, V55, and V60 in patients with RILSP versus control were 61.8% versus 52.8%, 44.4% versus 27.7%, 8.0% versus 0.3% and 1.8% versus 0%, respectively (P=0.01, 0.001, 0.001, and 0.001, respectively). Conclusion The delineation of the LSP during IMRT planning may reduce the risk for RILSP. The mean values of V40, V50, V55, and V60 for LSP should be less than 55%, 30%, 5%, and 0.5%, respectively; however, further studies are warranted. PMID:25565862

Tunio, Mutahir; Al Asiri, Mushabbab; Bayoumi, Yasser; Abdullah O Balbaid, Ali; AlHameed, Majid; Gabriela, Stanciu Laura; Amir O Ali, Ahmad

2015-01-01

13

Brachial plexus compression: a rare sequelae of malignant papillary thyroid carcinoma  

PubMed Central

Invasive papillary thyroid carcinoma (PTC) can rarely invade adjacent vital structures. There has been one report on secondary brachial plexopathy associated with locally invasive PTC. Here we report a patient with a large locally invasive PTC associated with secondary neoplastic brachial plexopathy. The case exhibits an extremely rare occurrence that has substantial impact on surgical planning and management. PMID:23936603

Patel, Amit S; Carter, John M; Friedlander, Paul L; Kandil, Emad

2013-01-01

14

[Brachial plexus tumors].  

PubMed

The brachial plexus is a primary site of tumours originating from peripheral nervous system, such as neurilemmoma and neurofibroma. Moreover, the brachial plexus is affected by various neoplasms spreading from the neighbouring anatomic structures. Surgical treatment of neoplasms provoking plexopathy is often realised by multidisciplinary teams. The authors present the series of 7 patients operated on for brachial plexus affection between 1993-2000, the pathologic findings were as follows: neurofibroma, neurilemmoma, lymphogranulomatosis, neurofibrosarcoma, lipoma, chordoma, sarcoma neurogenes. The analysis of clinical course includes: main symptoms, diagnostic procedures and results of treatment. Surgical technique is also described. PMID:12418135

Zapa?owicz, Krzysztof; Radek, Andrzej; ?yczak, Piotr; B?aszczyk, Bogdan; Skiba, Piotr

2002-01-01

15

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

16

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. PMID:23835205

2013-01-01

17

Brachial Plexus Neuritis Associated With Streptococcus agalactiae Infection: A Case Report  

PubMed Central

Brachial plexus neuritis is reportedly caused by various factors; however, it has not been described in association with Streptococcus agalactiae. This is a case report of a patient diagnosed with brachial plexus neuritis associated with pyogenic arthritis of the shoulder. A 57-year-old man visited the hospital complaining of sudden weakness and painful swelling of the left arm. The diagnosis was pyogenic arthritis of the left shoulder, and the patient was treated with open irrigation and debridement accompanied by intravenous antibiotic therapy. S. agalactiae was isolated from a wound culture, and an electrodiagnostic study showed brachial plexopathy involving the left upper and middle trunk. Nine weeks after onset, muscle strength improved in most of the affected muscles, and an electrodiagnostic study showed signs of reinnervation. In conclusion, S. agalactiae infection can lead to various complications including brachial plexus neuritis. PMID:25229037

Seo, Yu Jung; Lee, Yu Jin; Kim, Joon Sung; Lim, Seong Hoon

2014-01-01

18

Electrodiagnosis in traumatic brachial plexus injury  

PubMed Central

Electrodiagnosis (EDX) is a useful test to accurately localize the site, determine the extent, identify the predominant pathophysiology, and objectively quantify the severity of brachial plexopathies. It can also be used to examine muscles not easily assessed clinically and recognize minimal defects. Post-operatively and on follow up studies, it is important for early detection of re-innervation. It can be used intra-operatively to assess conduction across a neuroma, which would help the surgeon to decide further course of action. Localization of the site of the lesion can be very challenging as there may be multiple sites of involvement and hence the electroneuromyographic evaluation must be adequate. The unaffected limb also needs to be examined for comparison. The final impression must be co-related with the type and severity of injury. PMID:23661958

Mansukhani, K. A.

2013-01-01

19

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

20

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, ...

21

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 Plexus Injuries? Is there any treatment? What is the prognosis? What research ...

22

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

23

Radiation-induced sarcoma  

Microsoft Academic Search

Opinion statement  Radiation-induced sarcomas can originate in either the irradiated bone or soft tissues. Most of these tumors are high-grade.\\u000a The most common histologic subtypes are malignant fibrous histiocytoma (MFH) and osteosarcoma, although other histologies\\u000a (eg, angiosarcoma, rhabdomyosarcoma) can occur. Tumor size and grade are the two most important prognostic factors for soft tissue\\u000a sarcomas, including those associated with radiation therapy.

Shreyaskumar R. Patel

2000-01-01

24

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. PMID:23878776

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

2013-01-01

25

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

26

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

27

Radiation induced oral mucositis.  

PubMed

PATIENTS RECEIVING RADIOTHERAPY OR CHEMOTHERAPY WILL RECEIVE SOME DEGREE OF ORAL MUCOSITIS THE INCIDENCE OF ORAL MUCOSITIS WAS ESPECIALLY HIGH IN PATIENTS: (i) With primary tumors in the oral cavity, oropharynx, or nasopharynx; (ii) who also received concomitant chemotherapy; (iii) who received a total dose over 5,000 cGy; and (iv) who were treated with altered fractionation radiation schedules. Radiation-induced oral mucositis affects the quality of life of the patients and the family concerned. The present day management of oral mucositis is mostly palliative and or supportive care. The newer guidelines are suggesting Palifermin, which is the first active mucositis drug as well as Amifostine, for radiation protection and cryotherapy. The current management should focus more on palliative measures, such as pain management, nutritional support, and maintenance, of good oral hygiene. PMID:20668585

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

2009-07-01

28

Radiation-induced ignition  

SciTech Connect

The effects of gas-phase radiation absorption on radiative ignition of various combustible materials under gravity conditions are studied. The physical models in this study range from a simple gas layer to a complex porous structure. Methyl methacrylate (MMA: C{sub 5}H{sub 8}O{sub 2}) vapor has been selected as a representative of participating gases in gas-phase radiation interactions. Its infrared radiation properties were measured using low-resolution spectral apparatus and then correlated in simple usable forms. As expected from its complex molecular structure, the infrared absorption capabilities of MMA vapor is much stronger than those of simpler hydrocarbon gases as well as water vapor and carbon dioxide. Radiation induced ignition was analyzed on the basis of simple theoretical models. Using Semenov's theory, results indicate a decrease in the critical surrounding temperature for a low Biot number system. For a high Biot number system, ignitability is defined through the use of Frank-Kamenetskii's critical parameter delta. One-dimensional transient models were developed for the analyses of radiation induced ignition of solid and porous solid fuels. The models include gas-phase radiation absorption, in-depth radiation interaction by the solid phase, Arrhenius-type chemical reaction, and natural convection. Predicted transmittance during ignition processes confirms the attenuation of incident radiation by pyrolyzed gases which has been already observed experimentally. An ignition process with gas-phase radiation absorption results in a quite different and widened ignition domain compared to that without gas-phase radiation absorption. Moreover, ignition is totally dependent on gas-phase radiation absorption under unfavorable conditions for a thermal runaway.

Park, S.

1989-01-01

29

Radiation Induced Genomic Instability  

SciTech Connect

Radiation induced genomic instability can be observed in the progeny of irradiated cells multiple generations after irradiation of parental cells. The phenotype is well established both in vivo (Morgan 2003) and in vitro (Morgan 2003), and may be critical in radiation carcinogenesis (Little 2000, Huang et al. 2003). Instability can be induced by both the deposition of energy in irradiated cells as well as by signals transmitted by irradiated (targeted) cells to non-irradiated (non-targeted) cells (Kadhim et al. 1992, Lorimore et al. 1998). Thus both targeted and non-targeted cells can pass on the legacy of radiation to their progeny. However the radiation induced events and cellular processes that respond to both targeted and non-targeted radiation effects that lead to the unstable phenotype remain elusive. The cell system we have used to study radiation induced genomic instability utilizes human hamster GM10115 cells. These cells have a single copy of human chromosome 4 in a background of hamster chromosomes. Instability is evaluated in the clonal progeny of irradiated cells and a clone is considered unstable if it contains three or more metaphase sub-populations involving unique rearrangements of the human chromosome (Marder and Morgan 1993). Many of these unstable clones have been maintained in culture for many years and have been extensively characterized. As initially described by Clutton et al., (Clutton et al. 1996) many of our unstable clones exhibit persistently elevated levels of reactive oxygen species (Limoli et al. 2003), which appear to be due dysfunctional mitochondria (Kim et al. 2006, Kim et al. 2006). Interestingly, but perhaps not surprisingly, our unstable clones do not demonstrate a “mutator phenotype” (Limoli et al. 1997), but they do continue to rearrange their genomes for many years. The limiting factor with this system is the target – the human chromosome. While some clones demonstrate amplification of this chromosome and thus lend themselves to prolonged study, many tend to eliminate or rearrange the target chromosome until it is too small for further rearrangement. The observed frequency of induced instability by low and high linear-energy-transfer radiations greatly exceeds that observed for nuclear gene mutations at similar doses; hence, mutation of a gene or gene family is unlikely to be the initiating mechanism. Once initiated however, there is evidence in the GM10115 model system that it can be perpetuated over time by dicentric chromosome formation followed by bridge breakage fusion cycles (Marder and Morgan 1993), as well as recombinational events involving interstitial telomere like repeat sequences (Day et al. 1998). There is also increasing evidence that inflammatory type reactions (Lorimore et al. 2001, Lorimore and Wright 2003), presumably involving reactive oxygen and nitrogen species as well as cytokines and chemokines might be involved in driving the ustable phenotype (Liaikis et al. 2007, Hei et al. 2008). To this end there is very convincing evidence for such reactions being involved in another non-targeted effect associated with ionizing radiation, the bystander effect (Hei et al. 2008). Clearly the link between induced instability and bystander effects suggests common processes and inflammatory type reactions will likely be the subject of future investigation.

Morgan, William F.

2011-03-01

30

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. PMID:24433993

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

2013-01-01

31

Pitfalls in the electrodiagnostic studies of sacral plexopathies.  

PubMed

This retrospective review characterizes the electrodiagnostic (EDX) features and etiologies of sacral plexopathies (SPs) and discusses difficulties in their identification. The EDX findings of 171 clinically suspected SPs were reviewed using the following criteria: reduced/absent sensory nerve action potentials (SNAPs) of the sural or superficial peroneal nerve, denervation of plexus-innervated muscles, and the absence of paraspinal denervation. Sixty cases localized unequivocally to the sacral plexus. The majority were cancer-related, followed by traumatic, idiopathic, and iatrogenic causes. Final diagnoses in the remaining 111 cases were indeterminate. Lesions localized to either the plexus or L4-5, S1 roots in 52 cases, the plexus or sciatic nerve in 32 cases, and were equally compatible with an SP, sciatic neuropathy, or radiculopathy in 27 cases. Findings in the EDX evaluation of SPs are often complex and difficult to localize to a specific site due to multiple complicating factors. Frequently, SPs cannot be diagnosed definitively by EDX assessment alone. PMID:17366592

Tavee, Jinny; Mays, Maryann; Wilbourn, Asa J

2007-06-01

32

Obstetric brachial plexus injury  

PubMed Central

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

Thatte, Mukund R.; Mehta, Rujuta

2011-01-01

33

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

34

Radiation-induced genomic instability  

NASA Technical Reports Server (NTRS)

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

Kronenberg, A.

1994-01-01

35

Isolated latissimus dorsi transfer to restore shoulder external rotation in adults with brachial plexus injury.  

PubMed

In adults with brachial plexus injuries, lack of active external rotation at the shoulder is one of the most common residual deficits, significantly compromising upper limb function. There is a paucity of evidence to address this complex issue. We present our experience of isolated latissimus dorsi (LD) muscle transfer to achieve active external rotation. This is a retrospective review of 24 adult post-traumatic plexopathy patients who underwent isolated latissimus dorsi muscle transfer to restore external rotation of the shoulder between 1997 and 2010. All patients were male with a mean age of 34 years (21 to 57). All the patients underwent isolated LD muscle transfer using a standard technique to correct external rotational deficit. Outcome was assessed for improvement in active external rotation, arc of movement, muscle strength and return to work. The mean improvement in active external rotation from neutral was 24° (10° to 50°). The mean increase in arc of rotation was 52° (38° to 55°). Mean power of the external rotators was 3.5 Medical Research Council (MRC) grades (2 to 5). A total of 21 patients (88%) were back in work by the time of last follow up. Of these, 13 had returned to their pre-injury occupation. Isolated latissimus dorsi muscle transfer provides a simple and reliable method of restoring useful active external rotation in adults with brachial plexus injuries with internal rotational deformity. PMID:23632677

Ghosh, S; Singh, V K; Jeyaseelan, L; Sinisi, M; Fox, M

2013-05-01

36

Radiation-induced cardiovascular effects  

NASA Astrophysics Data System (ADS)

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

Tapio, Soile

37

[Ankle brachial index measurement].  

PubMed

Ultrasound examinations are noninvasive diagnostic methods which, along with appropriate history and clinical examination, provide basic information on the etiology and spread of the disease, as well as on treatment options required in patients with chronic venous insufficiency and arterial flow impairment. Doppler flow meter offers useful data on venous blood return, primarily in great veins, while both deep and superficial veins as well as arteries can be visualized and data on venous and arterial hemodynamics obtained by duplex ultrasonography. In addition, Doppler flow meter provides data on the peripheral arterial system action through ankle brachial index measurement, which will guide the choice of compression therapy when deciding on the treatment of peripheral arterial disease and mixed arteriovenous leg ulcers. However, diagnosis of arterial insufficiency requires additional examinations. PMID:25327002

Rucigaj, Tanja Planinsek

2014-10-01

38

MRI of the brachial plexus  

Microsoft Academic Search

Magnetic resonance imaging is the imaging method of first choice for evaluating the anatomy and pathology of the brachial\\u000a plexus. This review discusses the used imaging techniques, the normal anatomy, and a variety of pathologies that can involve\\u000a the brachial plexus. The pathology includes primary and secondary tumors (the most frequent secondary tumors being superior\\u000a sulcus tumor and metastatic breast

H. W. van Es

2001-01-01

39

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. PMID:22220245

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

2011-01-01

40

Perineural tumor spread of bladder cancer causing lumbosacral plexopathy: an anatomic explanation.  

PubMed

We present two cases of biopsy-proven neoplastic lumbosacral plexopathy from perineural spread of bladder cancer: one patient presented with predominantly sciatic nerve involvement and the second predominantly with obturator nerve involvement. These two patterns of perineural spread from bladder cancer were supported by imaging in our cases and solidified by review of the literature. Based on the innervation of the bladder, we provide an anatomic explanation for this observation. To our best knowledge, such an anatomic, mechanistic basis for perineural tumor spread in bladder cancer has not yet been described. PMID:25338118

Aghion, Daniel M; Capek, Stepan; Howe, Benjamin M; Hepel, Jaroslaw T; Sambandam, Sundaresan; Oyelese, Adetokunbo A; Oyelese, Adeotounbo A; Spinner, Robert J

2014-12-01

41

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

PubMed Central

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

Lantz, Andrea G.; Honey, R. John D’A

2015-01-01

42

Sonographic Mapping of the Normal Brachial Plexus  

Microsoft Academic Search

BACKGROUND AND PURPOSE: Mapping of the brachial plexus with MR imaging has been reported and may have potential clinical applications (eg, precise localization of traumatic or tumoral nerve lesions, selective anesthesia of the brachial plexus). We sought to demonstrate that mapping of the brachial plexus may be performed by means of sonography. METHODS: Twelve healthy adult volunteers (seven women and

Xavier Demondion; Pascal Herbinet; Nathalie Boutry; Christian Fontaine; Jean-Paul Francke; Anne Cotten

43

Ultrasound guided axillary brachial plexus block.  

PubMed

The axillary brachial plexus block is the most widely performed upper limb block. It is relatively simple to perform and one of the safest approaches to brachial plexus block. With the advent of ultrasound technology, there is a marked improvement in the success rate of the axillary block. This review will focus on the technique of ultrasound guided axillary brachial plexus block. PMID:25110766

Ranganath, Anil; Srinivasan, Karthikeyan Kallidaikurichi; Iohom, Gabriella

2014-09-01

44

Endovascular repair of a life-threatening radiation-induced ruptured false aneurysm of the intrathoracic left subclavian artery: case report  

PubMed Central

Massive hemorrhage in tracheostomy patients is generally described as a result of a tracheoinnominate artery fistula. Other etiologies for rupture of a false aneurysm are rare. The classical procedure for subclavian artery aneurysm is open surgery. Endovascular techniques have been accepted by several authors as a possible minimally invasive alternative. We report a life-threatening radiation-induced ruptured false aneurysm of the intrathoracic subclavian artery successfully treated by endovascular stent graft through left brachial access in a tracheostomy patient.

Hizette, Pascale; Horn, David; Lemaitre, Jean; Segers, Bernard

2015-01-01

45

Radiation-induced sarcoma of the thyroid  

SciTech Connect

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

Griem, K.L.; Robb, P.K.; Caldarelli, D.D.; Templeton, A.C. (Rush-Presbyterian-St Luke's Medical Center, Chicago, IL (USA))

1989-08-01

46

Diagnosis of brachial root and plexus lesions  

Microsoft Academic Search

The diagnosis and management of lesions of the brachial roots and of the brachial plexus is improved by appropriate investigation, both in acute and chronic disorders. The choice of investigation should be determined by the clinical problem. Since they are relatively non-invasive, electrophysiological investigations are particularly useful. In this review the role of these investigations is considered in relation to

M. Swash

1986-01-01

47

Radiation-induced brain injury: A review  

PubMed Central

Approximately 100,000 primary and metastatic brain tumor patients/year in the US survive long enough (>6 months) to experience radiation-induced brain injury. Prior to 1970, the human brain was thought to be highly radioresistant; the acute CNS syndrome occurs after single doses >30 Gy; white matter necrosis occurs at fractionated doses >60 Gy. Although white matter necrosis is uncommon with modern techniques, functional deficits, including progressive impairments in memory, attention, and executive function have become important, because they have profound effects on quality of life. Preclinical studies have provided valuable insights into the pathogenesis of radiation-induced cognitive impairment. Given its central role in memory and neurogenesis, the majority of these studies have focused on the hippocampus. Irradiating pediatric and young adult rodent brains leads to several hippocampal changes including neuroinflammation and a marked reduction in neurogenesis. These data have been interpreted to suggest that shielding the hippocampus will prevent clinical radiation-induced cognitive impairment. However, this interpretation may be overly simplistic. Studies using older rodents, that more closely match the adult human brain tumor population, indicate that, unlike pediatric and young adult rats, older rats fail to show a radiation-induced decrease in neurogenesis or a loss of mature neurons. Nevertheless, older rats still exhibit cognitive impairment. This occurs in the absence of demyelination and/or white matter necrosis similar to what is observed clinically, suggesting that more subtle molecular, cellular and/or microanatomic modifications are involved in this radiation-induced brain injury. Given that radiation-induced cognitive impairment likely reflects damage to both hippocampal- and non-hippocampal-dependent domains, there is a critical need to investigate the microanatomic and functional effects of radiation in various brain regions as well as their integration at clinically relevant doses and schedules. Recently developed techniques in neuroscience and neuroimaging provide not only an opportunity to accomplish this, but they also offer the opportunity to identify new biomarkers and new targets for interventions to prevent or ameliorate these late effects. PMID:22833841

Greene-Schloesser, Dana; Robbins, Mike E.; Peiffer, Ann M.; Shaw, Edward G.; Wheeler, Kenneth T.; Chan, Michael D.

2012-01-01

48

Radiation-induced neurological complications of nasopharyngeal carcinoma Radiation-induced neurological complications of nasopharyngeal carcinoma Radiation-induced neurological complications of nasopharyngeal carcinoma Radiation-induced neurological complications of nasopharyngeal carcinoma Radiation-induced neurological complications of nasopharyngeal carcinoma  

Microsoft Academic Search

Objectives: To review radiation-induced neurological complications of nasopharyngeal carcinoma (NPC). Materials & Methods: Retrospective review of patients with radiation-induced neurological complications of NPC who presented to the Neurology and Neurosurgery Departments, Tan Tock Seng Hospital in the five-year period from 1994 to 99. Results: Nine patients with 10 neurological complications were seen. Four patients had cranial nerve palsies, of whom

LCS Tan; YY Sitoh; HTL Tjia

1999-01-01

49

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

50

Radiation-induced meningiomas in pediatric patients  

SciTech Connect

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

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

1988-04-01

51

Radiation induced fracture of the scapula  

SciTech Connect

A case of radiation induced osteonecrosis resulting in a fracture of the scapula in a 76-yr-old female patient with a history of breast carcinoma is presented. Diagnostic imaging, laboratory recommendations and clinical findings are discussed along with an algorithm for the safe management of patients with a history of cancer and musculoskeletal complaints. This case demonstrates the necessity of a thorough investigation of musculoskeletal complaints in patients with previous bone-seeking carcinomas.

Riggs, J.H. III; Schultz, G.D.; Hanes, S.A. (Los Angeles College of Chiropractic, Whittier, CA (USA))

1990-10-01

52

Modeling radiation-induced cell cycle delays  

Microsoft Academic Search

Ionizing radiation is known to delay the cell cycle progression. In particular after particle exposure significant delays\\u000a have been observed and it has been shown that the extent of delay affects the expression of damage, such as chromosome aberrations.\\u000a Thus, to predict how cells respond to ionizing radiation and to derive reliable estimates of radiation risks, information\\u000a about radiation-induced cell

Anna Ochab-Marcinek; Ewa Gudowska-Nowak; Elena Nasonova; Sylvia Ritter

2009-01-01

53

Radiation induced transformation of CO in cyclohexane  

NASA Astrophysics Data System (ADS)

The radiation induced incorporation of CO in cyclohexane leads to formation of: bicyclohexylketone ( Gi = 2.40), ?, ?-bicyclohexyldiketone ( Gi = 0.90), cyclohexanone ( Gi = 0.24), cyclohexanol ( Gi = 0.20), cyclohexanecarboxylic acid ( Gi = 0.10), in addition to bicyclohexyl ( Gi = 1.30) and polymers. The G i-values are strongly dependent on the CO-concentration in the solution. Probable reaction mechanisms are presented.

Lugovoi, Y. M.; Park, H.-R.; Getoff, N.

54

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

SciTech Connect

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

Truong, Minh Tam, E-mail: mitruong@bu.edu [Department of Radiation Oncology, Boston Medical Center and Boston University School of Medicine, Boston, MA (United States); Romesser, Paul B.; Qureshi, Muhammad M.; Kovalchuk, Nataliya; Orlina, Lawrence; Willins, John [Department of Radiation Oncology, Boston Medical Center and Boston University School of Medicine, Boston, MA (United States)] [Department of Radiation Oncology, Boston Medical Center and Boston University School of Medicine, Boston, MA (United States)

2012-09-01

55

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. PMID:22348250

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

2013-01-01

56

Quercetin Inhibits Radiation-Induced Skin Fibrosis  

PubMed Central

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

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

2013-01-01

57

Prostate cancer with perineural spread and dural extension causing bilateral lumbosacral plexopathy: case report.  

PubMed

Perineural tumor spread in prostate cancer is emerging as a mechanism to explain select cases of neurological dysfunction and as a cause of morbidity and tumor recurrence. Perineural spread has been shown to extend from the prostate bed to the lumbosacral plexus and then distally to the sciatic nerve or proximally to the sacral and lumbar nerves and even intradurally. The authors present a case of a bilateral neoplastic lumbosacral plexopathy that can be explained anatomically as an extension of the same process: from one lumbosacral plexus to the contralateral one utilizing the dural sac as a bridge between the opposite sacral nerve roots. Their theory is supported by sequential progression of symptoms and findings on clinical examinations as well as high-resolution imaging (MRI and PET/CT scans). The neoplastic nature of the process was confirmed by a sciatic nerve fascicular biopsy. The authors believe that transmedian dural spread allows continuity of a neoplastic process from one side of the body to the other. PMID:25658791

Capek, Stepan; Howe, Benjamin M; Tracy, Jennifer A; García, Joaquín J; Amrami, Kimberly K; Spinner, Robert J

2015-04-01

58

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

59

MR imaging of the brachial plexus  

Microsoft Academic Search

In this retrospective study we describe the MR imaging findings in 230 consecutive patients with suspected pathology in or near the brachial plexus. These patients were\\u000astudied from 1991 through to 1996.\\u000aChapter 2 describes the anatomy and the MR imaging techniques. As the anatomy\\u000aof the brachial plexus and the related structures is quite complicated, we eventually\\u000ause as

Hendrik Wouter van Es

1997-01-01

60

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

61

Renaissance of supraclavicular brachial plexus block.  

PubMed

Due to frequent complications, especially pneumothorax, supraclavicular brachial plexus block became less popular. Ultrasonography is a very powerful tool in modern medicine and a real milestone in regional anaesthesia. Ultrasound- guided supraclavicular brachial plexus block reduces the probability of major complications occurrence (like pneumothorax, Horner's syndrome, phrenic nerve palsy). In this review we present the usefulness of ultrasonographic imaging and how to perform efficient ultrasound-guided blockade safely. PMID:24643926

Sadowski, Marek; Tu?aza, Bernadeta; Lysenko, Lidia

2014-01-01

62

Radiation-induced craniofacial bone growth disturbances.  

PubMed

Multimodality treatment, including radiotherapy, chemotherapy, and surgery, is required for the management of head and neck cancer in pediatric patients. Despite the modern advances in radiation dosing and targeting techniques, the radiation damage to the growing craniofacial skeleton in children remains a significant clinical problem. The first part of this review summarizes the clinical effects of radiotherapy on craniofacial bone growth in children. Experimental evidence on therapeutic radiation effects on bone growth in in vivo and in vitro models is reviewed. The second part of this review focuses on prevention of radiation-induced craniofacial bone growth inhibition using radioprotective agents. PMID:17912072

Gevorgyan, Artur; La Scala, Giorgio C; Neligan, Peter C; Pang, Cho Y; Forrest, Christopher R

2007-09-01

63

Idiopathic Brachial Plexitis After Total Shoulder Replacement with Interscalene Brachial Plexus Block  

Microsoft Academic Search

e describe a case of idiopathic brachial plexitis (IBP) that occurred after total shoulder re- placement with an interscalene brachial plexus block. A unique aspect of the case was full recovery of neurological function before release from the postanesthesia care unit (PACU) with the onset of new neurological symptoms 12-18 h later. Case Report A 65-year old woman was scheduled

JOHN E. TETZLAFF; JOHN DILGER; ENGLOK YAP; JOHN BREMS

1998-01-01

64

Radiation induced conductivity in space dielectric materials  

SciTech Connect

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

Hanna, R. [DESP, The French Aerospace Lab, 2 avenue Edouard Belin, 31055 Toulouse (France); Energie, SUPELEC, 3 rue Joliot Curie, 91192 Gif sur Yvette (France); CNES, 18 avenue Edouard Belin, 31401 Toulouse (France); Paulmier, T., E-mail: thierry.paulmier@onera.fr; Belhaj, M.; Dirassen, B. [DESP, The French Aerospace Lab, 2 avenue Edouard Belin, 31055 Toulouse (France); Molinie, P. [Energie, SUPELEC, 3 rue Joliot Curie, 91192 Gif sur Yvette (France); Payan, D.; Balcon, N. [CNES, 18 avenue Edouard Belin, 31401 Toulouse (France)

2014-01-21

65

Radiation-induced mutation at minisatellite loci  

SciTech Connect

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

Dubrova, Y.E. [Univ. of Leicester (United Kingdom)]|[Vavilov Institute of General Genetics, Moscow (Russian Federation); Nesterov, V.N.; Krouchinsky, N.G. [Research Institute for Radiation Medicine, Mogilev (Belarus)] [and others

1997-10-01

66

Radiation-Induced Spinal Cord Hemorrhage (Hematomyelia)  

PubMed Central

Intraspinal hemorrhage is very rare and intramedullary hemorrhage, also called hematomyelia, is the rarest form of intraspinal hemorrhage, usually related to trauma. Spinal vascular malformations such intradural arteriovenous malformations are the most common cause of atraumatic hematomyelia. Other considerations include warfarin or heparin anticoagulation, bleeding disorders, spinal cord tumors. Radiation-induced hematomyelia of the cord is exceedingly rare with only one case in literature to date. We report the case of an 8 year old girl with Ewing’s sarcoma of the thoracic vertebra, under radiation therapy, presenting with hematomyelia. We describe the clinical course, the findings on imaging studies and the available information in the literature. Recognition of the clinical pattern of spinal cord injury should lead clinicians to perform imaging studies to evaluate for compressive etiologies. PMID:25568739

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

2014-01-01

67

Radiation-induced mutations and plant breeding  

SciTech Connect

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

Naqvi, S.H.M.

1985-01-01

68

[Theoretical model of radiation-induced cancer].  

PubMed

A model of the dose dependence of the incidence of radiation-induced malignant tumors is proposed to provide a reliable estimation of the carcinogenic risk from low-level radiation. The model describes three main routs (cellular, tissue and system ones) by which radiation influences carcinogenesis. In terms of the two-stage theory of carcinogenesis, the first route deals with the initiating effect of radiation, and the second and third routs, with its promotion action. The proposed model gives a satisfactory combined description of the leukaemogenic effect of gamma-rays and neutrons. A theoretical explanation is presented of the differences in the pattern of the dose dependences of the yield of similar forms of the induced cancer exhibited by radiosensitive and radioresistant animal strains. PMID:6473724

Petoian, I M; Filiushkin, I V

1984-01-01

69

Brachial Artery Injury Accompanying Closed Elbow Dislocations  

PubMed Central

Introduction Brachial artery injuries from elbow dislocations are uncommon, but they may lead to disastrous consequences if the diagnosis is delayed. Presentation of case We report a case of a patient who sustained a fall onto the elbow, with dislocation and brachial artery injury, despite an ipsilateral radial pulse being palpable. Discussion Clinicians should maintain a high index of suspicion for brachial injury when patients present with a fall onto the elbow coupled with signs suggestive of fracture-dislocation, nerve injury and/or signs of limb ischemia. Frank ischamia, however, is uncommon as there is a rich collateral anastomosis in the upper limb. Conclusion A high index of suspicion should be maintained in order to make the diagnosis early. Exploration with excision of the injured segment and reverse vein interposition grafting is the treatment of choice in these cases. PMID:25644552

Harnarayan, Patrick; Cawich, Shamir O.; Harnanan, Dave; Budhooram, Steve

2014-01-01

70

Countermeasures for Space Radiation Induced Malignancies and Acute Biological Effects  

Microsoft Academic Search

The hypothesis being evaluated in this research program is that control of radiation induced oxidative stress will reduce the risk of radiation induced adverse biological effects occurring as a result of exposure to the types of radiation encountered during space travel. As part of this grant work, we have evaluated the protective effects of several antioxidants and dietary supplements and

Ann Kennedy

2008-01-01

71

Theory Of Radiation-Induced Attenuation In Optical Fibers  

NASA Technical Reports Server (NTRS)

Improved theory of radiation-induced attenuation of light in optical fibers accounts for effects of dose rates. Based on kinetic aspects of fundamental physics of color centers induced in optical fibers by radiation. Induced attenuation is proportional to density of color centers, and part of this density decays by thermal-annealing/recombination process after irradiation.

Liu, Tsuen-Hsi; Johnston, Alan R.

1996-01-01

72

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

73

Brachial Plexus Injury at Cesarean Section  

Microsoft Academic Search

\\u000a Brachial plexus traction injury can occur at the time of cesarean section delivery. This results from the operator’s failure\\u000a to recognize soft tissue incisional dystocia. Avoiding traction on the infant’s head and enlarging the incision in the uterus\\u000a and\\/or abdominal wall will prevent infant and maternal injury.

Michael S. Kreitzer; James A. O’Leary

74

Brachial plexus injury and obstetrical risk factors  

Microsoft Academic Search

Objective: To determine whether known historical risk factors of brachial plexus injury differ between affected neonates and healthy controls. Methods: The files of all 62 children with Erb's palsy who were diagnosed after birth were reviewed. The control group consisted of 124 randomly selected uninjured infants born within the same period. Results: Compared with the control group, the mothers of

J Bar; A Dvir; M Hod; R Orvieto; P Merlob; A Neri

2001-01-01

75

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. PMID:23644864

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

2013-01-01

76

Radiation-Induced Amorphization of Crystalline Ice  

NASA Technical Reports Server (NTRS)

We study radiation-induced amorphization of crystalline ice, ana lyzing the resu lts of three decades of experiments with a variety of projectiles, irradiation energy, and ice temperature, finding a similar trend of increasing resistance of amorphization with temperature and inconsistencies in results from different laboratories. We discuss the temperature dependence of amorphization in terms of the 'thermal spike' model. We then discuss the common use of the 1.65 micrometer infrared absorption band of water as a measure of degree of crystallinity, an increasingly common procedure to analyze remote sensing data of astronomical icy bodies. The discussion is based on new, high quality near-infrared refl ectance absorption spectra measured between 1.4 and 2.2 micrometers for amorphous and crystalline ices irradiated with 225 keV protons at 80 K. We found that, after irradiation with 10(exp 15) protons per square centimeter, crystalline ice films thinner than the ion range become fully amorphous, and that the infrared absorption spectra show no significant changes upon further irradiation. The complete amorphization suggests that crystalline ice observed in the outer Solar System, including trans-neptunian objects, may results from heat from internal sources or from the impact of icy meteorites or comets.

Fama, M.; Loeffler, M. J.; Raut, U.; Baragiola, R. A.

2009-01-01

77

Radiation-induced morphea - a literature review.  

PubMed

Radiation-induced morphea (RIM) is a rare and under-recognized skin complication of radiotherapy. It is commonly wrongly diagnosed as other dermatological conditions or malignancy because of similar clinical characteristics. This literature review analyses 66 cases that have been reported in the literature since 1989. The clinical appearance often includes pain and disfiguration of affected area, which may influence the patient's quality of life. There is no clear connection between the radiotherapy dose, the fractionation scheme, the use of a boost, age, the presence of other dermatological conditions or other connective tissue diseases and the occurrence of RIM. Its pathogenesis is still unclear, but several theories are proposed to explain this phenomenon. The available data suggest that the abnormally high secretion of some cytokines (interleukin 4, interleukin 5, transforming growth factor) induced by radiation causes an extensive fibrosis after an activation of fibroblasts. Histological confirmation is crucial in distinguishing RIM from similar-looking diseases, such as chronic radiation dermatitis, cancer recurrence, radiation, recall dermatitis, new carcinoma or cellulitis. There is no clear treatment regimen for this condition. Clinical outcome after therapy is often unsatisfactory. The commonly used methods and agents include: topical and systemic steroids, calcineurin inhibitors, systemic immunosuppressants including methotrexate, tacrolimus, heparin, hyaluronidase, phototherapy (UVA, UVA1, UVB, PUVA), systemic antibiotics, imiquimod, mycophenolate mofetil, photophoresis. The differential diagnosis is challenging and requires a multidisciplinary approach to avoid misdiagnosis and to plan appropriate treatment. PMID:25174551

Spalek, M; Jonska-Gmyrek, J; Ga?ecki, J

2015-02-01

78

Radiation-induced segregation in complex alloys  

SciTech Connect

Radiation-induced segregation (RIS) of alloying elements to the surface during 3 MeV /sup 58/Ni/sup +/ ion bombardment was investigated in alloys of Fe-200Cr-12Ni (at. %) containing controlled additions of Si and Mo. The segregation profiles, determined by Auger electron spectroscopy, show that Ni and Si are enriched, while Cr and Mo are depleted at the irradiated surfaces. The data indicates that the RIS of Ni and Cr are affected by the presence of Mo and Si in the alloy. However, no obvious trends are observed as a function of the minor solute element concentration. The temperature dependence of the RIS of the alloying elements was also investigated. A maximum of segregation at approx. 500/sup 0/C is observed for Si followed by a minimum and then a sharp increase in segregation at temperatures above 600/sup 0/C. The temperature dependence of segregation for Cr, Ni and Mo shows continous increase with temperature in the temperature regime investigated. The void swelling data on these alloys is also presented as a function of temperature and composition. Additions of Si reduce the swelling by affecting both the nucleation and the growth of the voids. The peak swelling temperature for all the alloys containing minor solutes are found to be lower (approx. 50/sup 0/C) than that of the base alloy (peak swelling temperature approx. 660/sup 0/C).

Sethi, V.K.; Okamoto, P.R.

1980-01-01

79

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

80

Ankle/brachial index to everyone  

PubMed Central

Background In the last years significant attention has been paid in identifying markers of subclinical atherosclerosis or of increased cardiovascular risk. Method An abnormal ankle/brachial index (ABI) identifies patients affected by lower extremity peripheral arterial disease, and even more important, represents a powerful predictor of the development of future ischemic cardiovascular events. Conclusions In our opinion, ABI is a cardiovascular risk prediction tool with very desirable properties that might become a routine measurement in clinical practice. PMID:23173985

2012-01-01

81

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. PMID:24967125

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

2014-01-01

82

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

83

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. PMID:19789638

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

2010-01-01

84

Radiation-induced myeloid leukemia in murine models  

PubMed Central

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

2014-01-01

85

Radiation-induced myeloid leukemia in murine models.  

PubMed

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

Rivina, Leena; Davoren, Michael; Schiestl, Robert H

2014-01-01

86

Doppler assessment: calculating an ankle brachial pressure index.  

PubMed

An ankle brachial pressure index (ABPI) is a simple non-invasive method of identifying arterial insufficiency within a limb. It compares the ankle and brachial systolic blood pressures. An important factor determining the rate of healing of any wound is adequate arterial blood supply. In the management of leg ulcers, the ABPI forms a fundamental part of the assessment. PMID:14618994

Ruff, Deborah

87

Dexamethasone Added to Lidocaine Prolongs Axillary Brachial Plexus Blockade  

Microsoft Academic Search

Different additives have been used to prolong regional blockade. We designed a prospective, randomized, double-blind study to evaluate the effect of dexameth- asone added to lidocaine on the onset and duration of axillary brachial plexus block. Sixty patients scheduled for elective hand and forearm surgery under axillary brachial plexus block were randomly allocated to re- ceive either 34 mL lidocaine

Ali Movafegh; Mehran Razazian; Fatemeh Hajimaohamadi; Alipasha Meysamie

2006-01-01

88

Three-Dimensional MR Imaging of the Brachial Plexus.  

PubMed

Pathologic conditions of the brachial plexus often result in serious and disabling complications. With the increasing availability and use of new and powerful MRI sequences and coils, understanding and assessment of the complex anatomy and pathology of the brachial plexus have been greatly facilitated. These new technical developments have led to an improved assessment of brachial plexus lesions, thereby improving patient care. In this article we describe various MRI techniques for the evaluation of the brachial plexus obtained at 1.5 T and 3 T, and we explain differences and similarities between sequences and protocols performed on MRI equipment from different vendors. The main characteristics of pathologic conditions affecting the brachial plexus are discussed and illustrated, as well as their differential diagnoses, with an emphasis on key imaging findings and relevance for patient management. Pitfalls related to suboptimal technique and image interpretation are also addressed. PMID:25764238

Vargas, Maria Isabel; Gariani, Joanna; Delattre, Benedicte A; Dietemann, Jean-Louis; Lovblad, Karl; Becker, Minerva

2015-04-01

89

The Mechanisms of Radiation-Induced Bystander Effect  

PubMed Central

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

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

2014-01-01

90

Panretinal photocoagulation for radiation-induced ocular ischemia  

SciTech Connect

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

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

1987-08-01

91

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

PubMed

The number of radiotherapy in the treatment of malignant diseases is increasing worldwide. During the radiotherapy of tumors in the minor pelvis and abdomen intestinal inflammation of different degree may occur even if special attention is paid. Irradiation to the minor pelvis causes in half of the cases radiation induced acute enteritis, whereas in 25% chronic enteritis and colitis will develop. Chronic enteritis following radiotherapy raises a number of diagnostic and therapeutic problems that can be solved only with cooperation of different specialties. Authors present a short review regarding therapeutical options of radiation induced enteritis. PMID:20739262

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

2010-09-01

92

The mechanisms of radiation-induced bystander effect.  

PubMed

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

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

2014-12-01

93

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

94

SPHINX Measurements of Radiation Induced Conductivity of Foam  

SciTech Connect

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

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

1998-12-14

95

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...

96

Laser therapy for severe radiation-induced rectal bleeding  

SciTech Connect

Four patients with chronic hematochezia and transfusion-dependent anemia from postradiation rectal vascular lesions were successfully managed by endoscopic laser coagulation. In all four patients, symptomatic, hematologic, and endoscopic improvement was evident. Laser therapy for severe radiation-induced rectal bleeding seems to be safe and efficacious and should be considered before surgical intervention.

Ahlquist, D.A.; Gostout, C.J.; Viggiano, T.R.; Pemberton, J.H.

1986-12-01

97

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

98

Obstructive jaundice due to radiation-induced hepatic duct stricture  

SciTech Connect

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

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

1984-10-01

99

Motor Cortex Neuroplasticity Following Brachial Plexus Transfer  

PubMed Central

In the past decade, research has demonstrated that cortical plasticity, once thought only to exist in the early stages of life, does indeed continue on into adulthood. Brain plasticity is now acknowledged as a core principle of brain function and describes the ability of the central nervous system to adapt and modify its structural organization and function as an adaptive response to functional demand. In this clinical case study we describe how we used neuroimaging techniques to observe the functional topographical expansion of a patch of cortex along the sensorimotor cortex of a 27-year-old woman following brachial plexus transfer surgery to re-innervate her left arm. We found bilateral activations present in the thalamus, caudate, insula as well as across the sensorimotor cortex during an elbow flex motor task. In contrast we found less activity in the sensorimotor cortex for a finger tap motor task in addition to activations lateralized to the left inferior frontal gyrus and thalamus and bilaterally for the insula. From a pain perspective the patient who had experienced extensive phantom limb pain (PLP) before surgery found these sensations were markedly reduced following transfer of the right brachial plexus to the intact left arm. Within the context of this clinical case the results suggest that functional improvements in limb mobility are associated with increased activation in the sensorimotor cortex as well as reduced PLP. PMID:23966938

Dimou, Stefan; Biggs, Michael; Tonkin, Michael; Hickie, Ian B.; Lagopoulos, Jim

2013-01-01

100

Fetal deformations: a risk factor for obstetrical brachial plexus palsy?  

PubMed

The purpose of this report is to discuss the association of brachial plexus palsy and congenital deformations. We reviewed all charts of patients less than 1 year of age with obstetrical brachial plexus palsy evaluated by one of the authors (IA) between January 1998 and October 2005 at Miami Children's Hospital Brachial Plexus Center. Of 158 patients with obstetrical brachial plexus palsy, 7 had deformations (4.4%). Deformations were present in 32% of patients delivered by cesarean section, but in only 2% of patients delivered vaginally. The deformations were ipsilateral, involving the chest in two patients, distal arms in two patients, proximal arm in one patient, ear in one patient, and the leg in one patient. All patients with deformations had unilateral Erb's palsies. None had a history of maternal uterine malformation. Two presumptive mechanisms of injury, one causing the deformation (compressive forces) and one causing brachial plexus palsy at the time of delivery (traction forces), were present in all cases. The higher incidence of deformation in patients with obstetrical brachial plexus palsy born by cesarean sections and the presence of two presumptive mechanisms in all of the cases presented here raises the possibility that fetal deformations are a risk factor for obstetrical brachial plexus palsy. PMID:16996396

Alfonso, Israel; Diaz-Arca, Gemma; Alfonso, Daniel T; Shuhaiber, Hans H; Papazian, Oscar; Price, Andrew E; Grossman, John A I

2006-10-01

101

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. PMID:24967130

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

102

Electroacupuncture attenuates neuropathic pain after brachial plexus injury  

PubMed Central

Electroacupuncture has traditionally been used to treat pain, but its effect on pain following brachial plexus injury is still unknown. In this study, rat models of an avulsion injury to the left brachial plexus root (associated with upper-limb chronic neuropathic pain) were given electroacupuncture stimulation at bilateral Quchi (LI11), Hegu (LI04), Zusanli (ST36) and Yanglingquan (GB34). After electroacupuncture therapy, chronic neuropathic pain in the rats’ upper limbs was significantly attenuated. Immunofluorescence staining showed that the expression of ?-endorphins in the arcuate nucleus was significantly increased after therapy. Thus, experimental findings indicate that electroacupuncture can attenuate neuropathic pain after brachial plexus injury through upregulating ?-endorphin expression. PMID:25221593

Zhang, Shenyu; Tang, Hailiang; Zhou, Junming; Gu, Yudong

2014-01-01

103

Modeling radiation-induced mixing at interfaces between low solubility metals  

E-print Network

This thesis studies radiation-induced mixing at interfaces between low solubility metals using molecular dynamics (MD) computer simulations. It provides original contributions on the fundamental mechanisms of radiation-induced ...

Zhang, Liang, Ph. D. Massachusetts Institute of Technology

2014-01-01

104

Comparison of radiation-induced transmission degradation of borosilicate crown optical glass from four different manufacturers  

E-print Network

Comparison of radiation-induced transmission degradation of borosilicate crown optical glass from manufacturers is different. We studied the gamma-radiation induced absorption of several crown glasses with nd compare the gamma-radiation induced absorption of several crown glasses with nd 1.516 (d = 587.56 nm

Glebov, Leon

105

[Myxoid/round cell liposarcoma of the brachial plexus].  

PubMed

Myxoid/round cell liposarcoma is a soft tissue sarcoma that is extremely rare in the brachial plexus. We report a case of a myxoid/round cell liposarcoma originating in the brachial plexus that was surgically resected and evolved well, with no deficit or recurrence after 2 years of follow-up. To date, there has been no other case of this sarcoma in the literature. PMID:25126709

Giner, Javier; Isla, Alberto; Hernández, Borja; Nistal, Manuel

2014-01-01

106

Caffeine Markedly Enhanced Radiation-Induced Bystander Effects  

NASA Astrophysics Data System (ADS)

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

Jiang, Erkang; Wu, Lijun

2009-04-01

107

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

108

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

109

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

110

Heavy-ion radiation induced bystander effect in mice  

NASA Astrophysics Data System (ADS)

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

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

2012-07-01

111

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

112

Radiation induced decomposition of hydrocarbons in water resources  

NASA Astrophysics Data System (ADS)

Radiation induced decomposition of various organic compounds, such as phenols, chlorinated hydrocarbons, dyestuffs etc. in water represents a new and very efficient possibility for elimination of the steadily increasing pollution. Experimental results considering the removal of phenol, phenolic compounds, mixture of aliphatic and aromatic hydrocarbons, as well as chlorinated compounds etc. in waste water under irradiation were reported. Basic considerations of probable reaction mechanisms were also presented.

Getoff, N.; Lutz, W.

113

Radiation-induced space-charge buildup in MOS structures  

Microsoft Academic Search

An analysis of a simple model for radiation-induced space-charge buildup in the SiO2layers of MOS structures has been carried out. The model assumes that hole-electron pairs are created in the SiO2by the radiation and that some of the electrons thus created drift out of the SiO2layer under the action of an applied potential across the oxide, VG, while the corresponding

J. P. Mitchell

1967-01-01

114

Get the LEAD out: noninvasive assessment for lower extremity arterial disease using ankle brachial index and toe brachial index measurements.  

PubMed

Lower extremity arterial disease affects approximately one third of individuals 66 years of age and older and has a high risk for nonhealing wounds, infection, and limb loss. Much wound care is given by or under the direction of nurses. Therefore, the assessment and management of these patients presents many opportunities and challenges. Assessment is the cornerstone of effective care, but traditional methods of lower extremity arterial assessment, such as pulse palpation and pain history, are insufficient to determine the presence and extent of ischemia. Recently published national guidelines for assessment and management of patients with lower extremity wounds have recommended using noninvasive tests such as the ankle brachial index and toe brachial index to rule out lower extremity arterial disease, which complicates wound healing. However, the ankle brachial index can be falsely elevated in patients with diabetes and renal failure because of calcification of the arteries, which causes them to be incompressible. In these situations, it has been advised to obtain a toe pressure or toe brachial index because digital arteries are usually less affected by calcification. There is a paucity of data about the knowledge of principles and performance of the ankle brachial index/toe brachial index by nurses, particularly in the United States, using pocket-sized portable Doppler equipment. Therefore, the purpose of this article is to provide an overview and synthesis of relevant studies and published expert opinion regarding noninvasive arterial assessment using ankle brachial and toe brachial indexes as a basis for developing protocols for performing the tests and identifying gaps in research where further investigation is needed. PMID:16444101

Bonham, Phyllis A

2006-01-01

115

Radiation-induced chromosomal aberrations at different dose-rates  

E-print Network

the damage is not observable since the cells are in the interphase stage of mitosis, snd the manifestations of liver injury may be delayed until such time that the cells may enter mitoses. Cytological observations of radiation-induced mitotic aber... are in the radiosensitive state at the time of irradiation or does the injury remain latent until such time as the cells may enter the critical phase. In the testes, a rapidly dividing tissue, the results of irradiation are isamdiately manifested whereas in the liver...

McDaniel, Jackson Dean

1965-01-01

116

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

SciTech Connect

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

Hartman, E. Frederick; Zarick, Thomas Andrew; Sheridan, Timothy J.; Preston, E. [ITT Exelis Mission Systems, Colorado Springs, CO

2013-05-01

117

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

118

Facial reconstruction for radiation-induced skin cancer  

SciTech Connect

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

Panje, W.R.; Dobleman, T.J. (Univ. of Chicago, IL (USA))

1990-04-01

119

Exaggerated radiation-induced fibrosis in patients with systemic sclerosis  

SciTech Connect

Four patients with stable systemic sclerosis and limited skin involvement received radiation for the treatment of solid malignant neoplasms. Following localized irradiation, each patient developed an exaggerated cutaneous and internal fibrotic reaction in the irradiated areas. The surface area of fibrosis extended beyond the radiation portals employed, and the fibrotic process was poorly responsive to antifibrotic therapy. Three of the patients died of complications caused by fibrous encasement of internal organs. The extent and severity of postradiation fibrosis in these patients was distinctly unusual. These observations suggest that patients with systemic sclerosis are particularly susceptible to developing excessive radiation-induced fibrosis.

Varga, J.; Haustein, U.F.; Creech, R.H.; Dwyer, J.P.; Jimenez, S.A. (Department of Medicine, Jefferson Medical College, Philadelphia, PA (USA))

1991-06-26

120

Clinical and neuropathological study about the neurotization of the suprascapular nerve in obstetric brachial plexus lesions  

Microsoft Academic Search

BACKGROUND: The lack of recovery of active external rotation of the shoulder is an important problem in children suffering from brachial plexus lesions involving the suprascapular nerve. The accessory nerve neurotization to the suprascapular nerve is a standard procedure, performed to improve shoulder motion in patients with brachial plexus palsy. METHODS: We operated on 65 patients with obstetric brachial plexus

Dominique Schaakxs; Jörg Bahm; Bernd Sellhaus; Joachim Weis

2009-01-01

121

Brachial plexus paresis associated with fetal neck compression from forceps.  

PubMed

Instrumental vaginal deliveries have been associated with higher risks of brachial plexus injuries. The proposed mechanisms involve the indirect association of instrumental deliveries with shoulder dystocia and nerve stretch injuries secondary to rotations of 90 degrees or more. We present a brachial plexus paresis resulting from direct compression of the forceps blade in the fetal neck. A term infant was delivered by a low Kielland forceps rotation. No shoulder dystocia was noted. The immediate neonatal exam revealed an Erb's palsy and an ipsilateral bruise in the lateral aspect of the neck. The paresis resolved during the first day of life. Direct cervical compression of the fetal neck by forceps in procedures involving rotations of the presentation may result in brachial plexus injuries. PMID:14528397

Gei, Alfredo F; Smith, Russell A; Hankins, Gary D V

2003-08-01

122

Nature of Radiation-Induced Defects in Quartz  

E-print Network

Although quartz ($\\rm \\alpha$-form) is a mineral used in numerous applications wherein radiation exposure is an issue, the nature of the atomistic defects formed during radiation-induced damage have not been fully clarified. Especially, the extent of oxygen vacancy formation is still debated, which is an issue of primary importance as optical techniques based on charged oxygen vacancies have been utilized to assess the level of radiation damage in quartz. In this paper, molecular dynamics (MD) simulations are applied to study the effects of ballistic impacts on the atomic network of quartz. We show that the defects that are formed mainly consist of over-coordinated Si and O, as well as Si--O connectivity defects, e.g., small Si--O rings and edge-sharing Si tetrahedra. Oxygen vacancies, on the contrary, are found in relatively low abundance, suggesting that characterizations based on $E^{\\prime}$ centers do not adequately capture radiation-induced structural damage in quartz. Finally, we evaluate the dependenc...

Wang, Bu; Pignatelli, Isabella; Sant, Gaurav N; Bauchy, Mathieu

2015-01-01

123

Nature of Radiation-Induced Defects in Quartz  

E-print Network

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

Bu Wang; Yingtian Yu; Isabella Pignatelli; Gaurav N. Sant; Mathieu Bauchy

2015-04-10

124

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

125

Radiation-induced dural fibrosarcoma with unusually short latent period  

SciTech Connect

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

Ghatak, N.R.; Aydin, F.; Leshner, R.T. (Medical College of Virginia, Richmond (United States) Tulane Univ., New Orleans, LA (United States))

1993-05-01

126

Ionizing Radiation Induces Delayed Hyperrecombination in Mammalian Cells  

PubMed Central

Exposure to ionizing radiation can result in delayed effects that can be detected in the progeny of an irradiated cell multiple generations after the initial exposure. These effects are described under the rubric of radiation-induced genomic instability and encompass multiple genotoxic endpoints. We have developed a green fluorescence protein (GFP)-based assay and demonstrated that ionizing radiation induces genomic instability in human RKO-derived cells and in human hamster hybrid GM10115 cells, manifested as increased homologous recombination (HR). Up to 10% of cells cultured after irradiation produce mixed GFP+/? colonies indicative of delayed HR or, in the case of RKO-derived cells, mutation and deletion. Consistent with prior studies, delayed chromosomal instability correlated with delayed reproductive cell death. In contrast, cells displaying delayed HR showed no evidence of delayed reproductive cell death, and there was no correlation between delayed chromosomal instability and delayed HR, indicating that these forms of genome instability arise by distinct mechanisms. Because delayed hyperrecombination can be induced at doses of ionizing radiation that are not associated with significantly reduced cell viability, these data may have important implications for assessment of radiation risk and understanding the mechanisms of radiation carcinogenesis. PMID:15143196

Huang, Lei; Grim, Suzanne; Smith, Leslie E.; Kim, Perry M.; Nickoloff, Jac A.; Goloubeva, Olga G.; Morgan, William F.

2004-01-01

127

Inhibition of radiation-induced polyuria by histamine receptor antagonists  

SciTech Connect

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

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

1986-03-01

128

Delayed Diagnosis of Probable Radiation Induced Spinal Cord Vascular Disorders  

PubMed Central

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

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

2015-01-01

129

Management of traumatic brachial plexus injuries in adults.  

PubMed

Adult brachial plexus injury (BPI) is a closed injury. It usually involves a plexus of nerves formed by a number of roots, spinal nerves, trunks, cords, and numerous terminal branches, in a complicated fashion. Successful results in the management of adult BPI are based on the knowledge of anatomic arrangement, pathophysiology considerations, preoperative evaluation and diagnosis, surgical technique, postoperative management, rehabilitation and regular patient follow-up, surgical treatment of sequelae deformities, and factors influencing its results. This article deals with traumatic lesions of the brachial plexus in adults, and focuses on controversial questions and philosophy of treatment of adult BPI. PMID:10563273

Chuang, D C

1999-11-01

130

Brachial artery pseudoaneurysm: a rare complication after haemodialysis therapy.  

PubMed

Haemodialysis patients carry a high risk of pseudoaneurysm due to inadvertent puncture of the brachial artery during venous cannulation for haemodialysis. Signs and symptoms are pulsatile mass and a systolic murmur. Complications are rupture, infection, haemorrhage, distal arterial insufficiency, venous thrombosis and neuropathy. Early diagnosis is essential to plan adequate treatment. Doppler US and angiography usually confirm the lesion accurately. Ultrasound guided compression, percutaneous injection of thrombin, endovascular covered stent exclusion, aneurysmectomy and surgical repair are different treatment options. We report clinical and radiological findings and treatment strategies in four dialysed patients who developed brachial artery pseudoaneurysms. PMID:15906913

Yildirim, S; Nursal, T Zafer; Yildirim, T; Tarim, A; Caliskan, K

2005-04-01

131

Massive hemothorax: A rare complication after supraclavicular brachial plexus block  

PubMed Central

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

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

2014-01-01

132

Radiation induced genome instability: multiscale modelling and data analysis  

NASA Astrophysics Data System (ADS)

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

Andreev, Sergey; Eidelman, Yuri

2012-07-01

133

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

134

Radioprotectors and Mitigators of Radiation-Induced Normal Tissue Injury  

PubMed Central

Radiation is used in the treatment of a broad range of malignancies. Exposure of normal tissue to radiation may result in both acute and chronic toxicities that can result in an inability to deliver the intended therapy, a range of symptoms, and a decrease in quality of life. Radioprotectors are compounds that are designed to reduce the damage in normal tissues caused by radiation. These compounds are often antioxidants and must be present before or at the time of radiation for effectiveness. Other agents, termed mitigators, may be used to minimize toxicity even after radiation has been delivered. Herein, we review agents in clinical use or in development as radioprotectors and mitigators of radiation-induced normal tissue injury. Few agents are approved for clinical use, but many new compounds show promising results in preclinical testing. PMID:20413641

Cotrim, Ana P.; Hyodo, Fuminori; Baum, Bruce J.; Krishna, Murali C.; Mitchell, James B.

2010-01-01

135

Factors that modify risks of radiation-induced cancer  

SciTech Connect

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

Fabrikant, J.I.

1988-11-01

136

Probabilistic methodology for estimating radiation-induced cancer risk  

SciTech Connect

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

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

1981-01-01

137

Radiation-Induced Heart Disease: Pathologic Abnormalities and Putative Mechanisms  

PubMed Central

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

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

2015-01-01

138

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

139

Ventricular Tachycardia Associated with Radiation-Induced Cardiac Sarcoma  

PubMed Central

Cardiac tumors can lead to distinct electrocardiographic changes and ventricular arrhythmias. Benign and malignant cardiac tumors have been associated with ventricular tachycardia. When possible, benign tumors should be resected when ventricular arrhythmias are intractable. Chemotherapy can shrink malignant tumors and eliminate arrhythmias. We report the case of a 52-year-old woman with breast sarcoma whom we diagnosed with myocardial metastasis after she presented with palpitations. The initial electrocardiogram revealed sinus rhythm with new right bundle branch block and ST-segment elevation in the anterior precordial leads. During telemetry, hemodynamically stable, sustained ventricular tachycardia with right ventricular localization was detected. Images showed a myocardial mass in the right ventricular free wall. Amiodarone suppressed the arrhythmia. To our knowledge, this is the first report of ventricular tachycardia associated with radiation-induced undifferentiated sarcoma. We discuss the distinct electrocardiographic changes and ventricular arrhythmias that can be associated with cardiac tumors, and we review the relevant medical literature. PMID:25593527

Beaty, Elijah H.; Ballany, Wassim; Trohman, Richard G.

2014-01-01

140

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

PubMed

Radiation-induced bystander effect (RIBE) is a biological process that has received attention over the past two decades. RIBE refers to a plethora of biological effects in non-irradiated cells, including induction of genetic damages, gene expression, cell transformation, proliferation and cell death, which are initiated by receiving bystander signals released from irradiated cells. RIBE brings potential hazards to normal tissues in radiotherapy, and imparts a higher risk from low-dose radiation than we previously thought. Detection with proteins related to DNA damage and repair, cell cycle control, proliferation, etc. have enabled rapid assessment of RIBE in a number of research systems such as cultured cells, three-dimensional tissue models and animal models. Accumulated experimental data have suggested that RIBE may be initiated rapidly within a time frame as short as several minutes after radiation. These have led to the requirement of techniques capable of rapidly assessing RIBE itself as well as assessing the early processes involved. PMID:24139967

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

2015-01-01

141

[Radiation-induced and therapy-related AML/MDS].  

PubMed

Radiation induced acute myeloid leukemia (AML) was recognized a century ago, soon after mankind found radiation. Atomic bomb survivors developed de novo AML with relatively short latency with very high frequency. By contrast, excess occurrence of myelodysplastic syndrome (MDS) as well as solid tumors was found decades late. This difference may be due to etiology that many de novo AML patients harbor chimeric leukemogenic genes caused by chromosomal translocations, while MDS patients rarely carry chimeras. In addition, epigenetic change would play important roles. Therapy related leukemia is mainly caused by topoisomerase II inhibitors that cause de novo AML with an 11q23 translocation or by alkyrating agents that induce MDS/AML with an AML1 point mutation and monosomy 7. PMID:19860183

Inaba, Toshiya

2009-10-01

142

Measurements of prompt radiation induced conductivity of alumina and sapphire.  

SciTech Connect

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

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

2011-04-01

143

Pulsed radiation-induced attenuation in certain optical fibers  

SciTech Connect

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

Weiss, J.D. (Sandia National Laboratories, Albuquerque, NM (United States))

1992-05-01

144

Factors that modify risks of radiation-induced cancer.  

PubMed

The collective influence of biologic, physical, and other factors that modify risks of radiation-induced cancer introduces uncertainties and assumptions that limit precision of estimates of human cancer risk that can be calculated for populations exposed to low-dose radiation. The important biologic characteristics include the tissue sites and cell types, baseline cancer incidence, latent periods, time-to-tumor recognition, and individual host (e.g., age and sex) and competing etiologic influences. Physical factors include radiation dose, dose rate, and radiation quality. Statistical factors include time-response projection models, risk coefficients, and dose-response relationships. Sources that modify risk also include other carcinogens and biologic factors (e.g., hormonal conditions, immune status, hereditary factors). Discussion includes examples of known influences that modify radiation-associated cancer risks and how they have been dealt with in the risk-estimation process, including extrapolation to low doses, use of relative risk models, and other uncertainties. PMID:2358362

Fabrikant, J I

1990-07-01

145

The Dose Window for Radiation-Induced Protective Adaptive Responses  

PubMed Central

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

Mitchel, Ronald E. J.

2009-01-01

146

The dose window for radiation-induced protective adaptive responses.  

PubMed

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

Mitchel, Ronald E J

2010-01-01

147

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

148

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

149

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 ¹³?Cs source at 0.9 Gy min?¹. Transepithelial short circuit current (I(sc)), 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

150

Bystander effects in radiation-induced genomic instability  

NASA Technical Reports Server (NTRS)

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

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

2002-01-01

151

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. PMID:23026565

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

2012-01-01

152

Learn the Brachial Plexus in Five Minutes or Less  

E-print Network

is the result of work supported with resources and the use of facilities at the VA Gulf Coast Veterans Health and Rehabilitation Department of Veterans Affairs, Biloxi, Mississippi and Dennis A. Chu, M.D. This material view of the Department of Veterans Affairs of the U.S. Government. #12;The brachial plexus contains

Finley Jr., Russell L.

153

A New Approach for Brachial Plexus Block Under Fluoroscopic Guidance  

Microsoft Academic Search

We performed the subclavian perivascular approach to the brachial plexus using contrast medium to confirm the location of the tip of the needle and the spread of the injected solution to obtain a high success rate and to minimize the risk of pneumothorax. Review of the cases led to the hypothesis that the solution injected inside the costal attachment of

Misuzu Nishiyama; Keiko Naganuma; Yoshikiyo Amaki

1999-01-01

154

Ankle–Brachial Index for Assessment of Peripheral Arterial Disease  

Microsoft Academic Search

Indications Although other methods exist to assess the peripheral vasculature more objectively, the ankle-brachial index represents a simple, reliable method for diagnosing pe- ripheral arterial disease. More specific indications include evaluation of leg pain, evaluation for ischemia of the legs (symptoms of claudication, pain at rest, and the presence of foot ulcers or gangrene), screening for atherosclerosis, and evaluation of

S. Marlene Grenon; Joel Gagnon; York Hsiang

2009-01-01

155

DIABETIC FOOT ULCER GRADES; CORRELATION WITH ANKLE BRACHIAL PRESSURE INDEX  

Microsoft Academic Search

Diabetic foot is one of the most common complications of diabetes mellitus. The management and out come is very much dependent on proper assessment of foot ulcer severity. Objectives: To asses severity of diabetic foot and to find a correlation between Ankle Brachial Pressure Index (ABPI) and foot ulcer grades. Study design: Prospective study. Period: Jan 2001 to Dec 2003.

ALI AKBAR; WAQAS ANWAR

156

MRI of axillary brachial plexus blocks  

PubMed Central

BACKGROUND Axillary plexus blocks are usually guided by ultrasound, but alternative methods may be used when ultrasound equipment is lacking. For a nonultrasound-guided axillary block, the need for three injections has been questioned. OBJECTIVES Could differences in block success between single, double and triple deposits methods be explained by differences in local anaesthetic distribution as observed by MRI? DESIGN A blinded and randomised controlled study. SETTING Conducted at Oslo University Hospital, Rikshospitalet, Norway from 2009 to 2011. PATIENTS Forty-five ASA 1 to 2 patients scheduled for surgery were randomised to three equally sized groups. All patients completed the study. INTERVENTIONS Patients in the single-deposit group had an injection through a catheter parallel to the median nerve. In the double-deposit group the patients received a transarterial block. In the triple-deposit group the injections of the two other groups were combined. Upon completion of local anaesthetic injection the patients were scanned by MRI, before clinical block assessment. The distribution of local anaesthetic was scored by its closeness to terminal nerves and cords of the brachial plexus, as seen by MRI. The clinical effect was scored by the degree of sensory block in terminal nerve innervation areas. MAIN OUTCOME MEASURES Sensory block effect and MRI distribution pattern. RESULTS The triple-deposit method had a higher success rate (100%) than the single-deposit method (67%) and the double-deposit method (67%) in blocking all cutaneous nerves distal to the elbow (P?=?0.04). The patients in the triple-deposit group most often had the best MRI scores. For any nerve or cord, at least one of the single-deposit or double-deposit groups had a similarly high MRI score as the triple-deposit group. CONCLUSION Distal to the elbow, the triple-deposit method had the highest sensory block success rate. This could be explained to some extent by analysis of the magnetic resonance images. TRIAL REGISTRATION ClinicalTrials.gov identifier: NCT01033006. PMID:25051144

Kjelstrup, Trygve; Hol, Per K.; Courivaud, Frédéric; Smith, Hans-Jørgen; Røkkum, Magne; Klaastad, Øivind

2014-01-01

157

Universal damage factor for radiation-induced dark current in silicon devices  

Microsoft Academic Search

A new damage factor formulation is presented for describing radiation-induced dark current in silicon devices. This damage factor, K dark, is the number of carriers thermally generated per unit volume per unit time in a depletion region per unit nonionizing dose deposited in that volume. Kdark appears to account successfully for the mean radiation-induced dark current for any silicon device

J. R. Srour; D. H. Lo

2000-01-01

158

Time course of radiation-induced apoptosis in the adult rat spinal cord  

Microsoft Academic Search

Radiation-induced apoptosis has been reported in thymic, lymphoid, haematopoietic cells and intestinal epithelium but is infrequently documented in other adult mammalian cell types. In this study, we examined the time course of radiation-induced apoptosis in the adult cervical rat spinal cord following a single dose of 8 or 22 Gy. Apoptosis was assessed by morphological criteria under light and electron

Y. Q. Li; Y. P. Guo; V. Jay; P. A. Stewart; C. S. Wong

1996-01-01

159

Simulating and Detecting Radiation-Induced Errors for Onboard Machine Learning  

E-print Network

Simulating and Detecting Radiation-Induced Errors for Onboard Machine Learning Robert Granat, Kiri-based fault tolerance (ABFT) methods into onboard data analysis algorithms to detect radiation-induced errors" machine learning algorithms. I. INTRODUCTION AND OBJECTIVES Onboard data analysis is a powerful capability

Wagstaff, Kiri L.

160

Effects of exogenous carbon monoxide on radiation-induced bystander effect in zebrafish embryos in vivo  

E-print Network

Effects of exogenous carbon monoxide on radiation-induced bystander effect in zebrafish embryos Zebrafish embryos CO CORM-3 a b s t r a c t In the present work, the influence of a low concentration) on the radiation induced bystander effect (RIBE) in vivo between embryos of the zebrafish was studied. RIBE

Yu, K.N.

161

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

PubMed Central

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

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

2014-01-01

162

Countermeasures for Space Radiation Induced Malignancies and Acute Biological Effects  

NASA Astrophysics Data System (ADS)

The hypothesis being evaluated in this research program is that control of radiation induced oxidative stress will reduce the risk of radiation induced adverse biological effects occurring as a result of exposure to the types of radiation encountered during space travel. As part of this grant work, we have evaluated the protective effects of several antioxidants and dietary supplements and observed that a mixture of antioxidants (AOX), containing L-selenomethionine, N-acetyl cysteine (NAC), ascorbic acid, vitamin E succinate, and alpha-lipoic acid, is highly effective at reducing space radiation induced oxidative stress in both in vivo and in vitro systems, space radiation induced cytotoxicity and malignant transformation in vitro [1-7]. In studies designed to determine whether the AOX formulation could affect radiation induced mortality [8], it was observed that the AOX dietary supplement increased the 30-day survival of ICR male mice following exposure to a potentially lethal dose (8 Gy) of X-rays when given prior to or after animal irradiation. Pretreatment of animals with antioxidants resulted in significantly higher total white blood cell and neutrophil counts in peripheral blood at 4 and 24 hours following exposure to doses of 1 Gy and 8 Gy. Antioxidant treatment also resulted in increased bone marrow cell counts following irradiation, and prevented peripheral lymphopenia following 1 Gy irradiation. Supplementation with antioxidants in irradiated animals resulted in several gene expression changes: the antioxidant treatment was associated with increased Bcl-2, and decreased Bax, caspase-9 and TGF-?1 mRNA expression in the bone marrow following irradiation. These results suggest that modulation of apoptosis may be mechanistically involved in hematopoietic system radioprotection by antioxidants. Maintenance of the antioxidant diet was associated with improved recovery of the bone marrow following sub-lethal or potentially lethal irradiation. Taken together, oral supplementation with antioxidants appears to be an effective approach for the radioprotection of hematopoietic cells against the cell killing effects of radiation, and for improving survival in irradiated animals. Preliminary data suggest similar antioxidant protective effects for animals exposed to potentially lethal doses of proton radiation. Studies were also performed to determine whether dietary antioxidants could affect the incidence rates of malignancies in CBA mice exposed to 300 cGy proton (1 GeV/n) radiation or 50 cGy iron ion (1 GeV/n) radiation [9]. Two antioxidant formulations were utilized in these studies; an AOX formulation containing the mixture of antioxidant agents developed from our previous studies and an antioxidant dietary formulation containing the soybean-derived protease inhibitor known as the Bowman-Birk inhibitor (BBI). BBI was evaluated in the form of BBI Concentrate (BBIC), which is the form of BBI utilized in human trials. BBIC has been utilized in human trials since 1992, as described [10]. The major finding in the long-term animal studies was that there was a reduced risk of malignant lymphoma in mice exposed to space radiations and maintained on diets containing the antioxidant formulations. In addition, the two different dietary countermeasures also reduced the yields of a variety of different rare tumor types, arising from both epithelial and connective tissue cells, observed in the animals exposed to space radiation. REFERENCES [1] Guan J. et al (2004) Radiation Research 162, 572-579. [2] Wan X.S. et al (2005) Radiation Research 163, 364-368. [3] Wan X.S. et al (2005) Radiation Research 163, 232-240. [4] Guan J. et al (2006) Radiation Research 165, 373-378. [5] Wan X.S. et al (2006) International Journal of Radiation Oncology, Biology, Physics 64, 1475-1481. [6] Kennedy A.R. et al (2006) Radiation Research 166, 327-332. [7] Kennedy A.R. et al (2007) Radiation & Environmental Biophysics 46(2), 201-3. [8]Wambi, C., Sanzari, J., Wan, X.S., Nuth, M., Davis, J., Ko, Y.-H., Sayers, C.M., Baran, M., Ware, J.H. and Kennedy, A

Kennedy, Ann

163

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

164

Radiation-Induced Alterations in Mitochondria of the Rat Heart  

PubMed Central

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

2014-01-01

165

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

PubMed Central

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

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

2014-01-01

166

Ionizing Radiation-Induced Cataract in Interventional Cardiology Staff  

PubMed Central

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

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

2015-01-01

167

Radiation-induced chromosomal instability in human mammary epithelial cells  

NASA Technical Reports Server (NTRS)

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.

1996-01-01

168

ULTRASTRUCTURAL STUDIES OF RADIATION-INDUCED CHROMOSOME DAMAGE  

PubMed Central

The fine structure of radiation-induced chromosomal aberrations in Potorous tridactylis (rat kangaroo) cells was examined in situ by electron microscopy. The observations on the structure of terminal deletions (acentric fragments), anaphase bridges and "gaps," sidearm bridges, and specialized regions, such as the nucleolus organizer, are discussed in detail. Conclusions based on these observations are the following: (a) damage is physically expressed only at anaphase; (b) a gap region is composed of two subunits, each of which is about 800–1000 A in diameter and may correspond to a half-chromatid structure; (c) the ends of acentric fragments are structurally similar to normal chromosome ends, except where the break occurs in a specific region such as the secondary constriction; (d) at metaphase the fragment and the main portion of the chromosome move as a single unit to the equator, and the two units are disconnected only at the onset of anaphase; (e) sidearm bridges appear to be exchanges, involving a subchromatid unit. The interpretation of this evidence is consistent with the hypothesis that the chromosome is a multistranded structure. PMID:4895598

Humphrey, Ronald M.; Brinkley, B. R.

1969-01-01

169

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

170

Radiation-induced optic neuropathy: A magnetic resonance imaging study  

SciTech Connect

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

Guy, J.; Mancuso, A.; Beck, R.; Moster, M.L.; Sedwick, L.A.; Quisling, R.G.; Rhoton, A.L. Jr.; Protzko, E.E.; Schiffman, J. (Univ. of Florida, Gainesville (USA))

1991-03-01

171

Radiation-induced sarcomas of the head and neck.  

PubMed

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

Thiagarajan, Anuradha; Iyer, N Gopalakrishna

2014-12-10

172

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

173

Radiation-induced sarcomas of the head and neck  

PubMed Central

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

Thiagarajan, Anuradha; Iyer, N Gopalakrishna

2014-01-01

174

Space-radiation-induced Photon Luminescence of the Moon  

NASA Technical Reports Server (NTRS)

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

Wilson, Thomas; Lee, Kerry

2008-01-01

175

Radiation induced thyroid neoplasms 1920 to 1987: A vanishing problem  

SciTech Connect

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

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

1989-06-01

176

Radiation-Induced Notch Signaling in Breast Cancer Stem Cells  

SciTech Connect

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

Lagadec, Chann [Department of Radiation Oncology, David Geffen School of Medicine at University of California, Los Angeles (UCLA), Los Angeles, California (United States); Vlashi, Erina [Department of Radiation Oncology, David Geffen School of Medicine at University of California, Los Angeles (UCLA), Los Angeles, California (United States); Jonsson Comprehensive Cancer Center at UCLA, Los Angeles, California (United States); Alhiyari, Yazeed; Phillips, Tiffany M.; Bochkur Dratver, Milana [Department of Radiation Oncology, David Geffen School of Medicine at University of California, Los Angeles (UCLA), Los Angeles, California (United States); Pajonk, Frank, E-mail: fpajonk@mednet.ucla.edu [Department of Radiation Oncology, David Geffen School of Medicine at University of California, Los Angeles (UCLA), Los Angeles, California (United States); Jonsson Comprehensive Cancer Center at UCLA, Los Angeles, California (United States)

2013-11-01

177

Chromatin Structure and Radiation-Induced Intrachromosome Exchange  

NASA Technical Reports Server (NTRS)

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

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

2011-01-01

178

The prefixed and postfixed brachial plexus: a review with surgical implications  

Microsoft Academic Search

The definition of a pre and postfixed brachial plexus is varied in the literature, which results in inconsistent conclusions\\u000a for various studies. As anatomical variation is important both during clinical evaluation and surgical procedures of the brachial\\u000a plexus, a review of this literature was performed. Based on our review, variation in the contribution to the brachial plexus\\u000a is more the

Megan Pellerin; Zachary Kimball; R. Shane Tubbs; Snow Nguyen; Petru Matusz; Aaron A. Cohen-Gadol; Marios Loukas

2010-01-01

179

Reoperation for failed shoulder reconstruction following brachial plexus birth injury  

PubMed Central

Background Various approaches have been developed to treat the progressive shoulder deformity in patients with brachial plexus birth palsy. Reconstructive surgery for this condition consists of complex procedures with a risk for failure. Case presentations This is a retrospective case review of the outcome in eight cases referred to us for reoperation for failed shoulder reconstructions. In each case, we describe the initial attempt(s) at surgical correction, the underlying causes of failure, and the procedures performed to rectify the problem. Results were assessed using pre- and post-operative Mallet shoulder scores. All eight patients realized improvement in shoulder function from reoperation. Conclusions This case review identifies several aspects of reconstructive shoulder surgery for brachial plexus birth injury that may cause failure of the index procedure(s) and outlines critical steps in the evaluation and execution of shoulder reconstruction. PMID:23883413

2013-01-01

180

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

181

Recent advances in the management of brachial plexus injuries  

PubMed Central

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

Bhandari, Prem Singh; Maurya, Sanjay

2014-01-01

182

Post-operative brachial plexus neuropraxia: A less recognised complication of combined plastic and laparoscopic surgeries  

PubMed Central

This presentation is to increase awareness of the potential for brachial plexus injury during prolonged combined plastic surgery procedures. A case of brachial plexus neuropraxia in a 26-year-old obese patient following a prolonged combined plastic surgery procedure was encountered. Nerve palsy due to faulty positioning on the operating table is commonly seen over the elbow and popliteal fossa. However, injury to the brachial plexus has been a recently reported phenomenon due to the increasing number of laparoscopic and robotic procedures. Brachial plexus injury needs to be recognised as a potential complication of prolonged combined plastic surgery. Preventive measures are discussed. PMID:25593443

Thomas, Jimmy

2014-01-01

183

Bilateral, hypertrophic neuritis of the brachial plexus in a cat: magnetic resonance imaging and pathological findings.  

PubMed

A 9-year-old Burmese cat was presented for investigation of a subacute onset of bilateral forelimb paresis. Magnetic resonance imaging of the cervico-thoracic vertebral column and brachial plexus revealed a bilaterally symmetrical, severe and diffuse swelling of the spinal nerves forming the caudal part of the brachial plexus. Histopathology of the abnormal nerve roots, spinal nerves and brachial plexi showed inflammatory and marked proliferative changes with similar features to that of hypertrophic neuritis of man. Hypertrophic neuritis in man is a rare, tumor-like, chronic inflammatory peripheral nerve disorder of unknown origin most frequently involving the brachial plexus. PMID:16213764

Garosi, Laurent; de Lahunta, Alexander; Summers, Brian; Dennis, Ruth; Scase, Tim

2006-02-01

184

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

PubMed Central

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

2013-01-01

185

SELF-MUTILATION IN CHILDREN WITH OBSTETRIC BRACHIAL PLEXUS PALSY  

Microsoft Academic Search

In a prospective study, the incidence and clinical presentation of self-mutilation was documented in 127 consecutive cases of obstetric brachial plexus injury. Six out of the 127 cases (4.7%) had clinical evidence of self-mutilation. The incidence of self-mutilation was much higher among children with total palsy (4\\/37) than Erb's palsy (2\\/90). All affected children were able to bring the mutilated

M. M AL-QATTAN

1999-01-01

186

[Traumatic lesions of the brachial plexus. Microsurgical treatment].  

PubMed

Extensive analysis of results of microsurgical treatment of brachial plexus injuries is based on the experience gained by Professor Ezio Morelli, Head of the Department of Plastic Surgery and Hand at the Civil Hospital, Legnano, Italy. The casuistic behind the aim of this report is an attempt to evaluate results obtained which demonstrate the validity of the proposed treatment and supply the elements useful for evaluation in the indications for this treatment. PMID:4044689

Pajardi, G; Morelli, E

1985-05-01

187

Aortic-brachial stiffness mismatch and mortality in dialysis population.  

PubMed

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

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

2015-02-01

188

Décompression chirurgicale du syndrome de défilé thoraco-brachial  

PubMed Central

Le syndrome de défilé thoraco-brachial est une pathologie souvent méconnue à cause de diagnostic difficile par manque des signes pathognomoniques conduisant souvent à des errances. Les manifestations cliniques dépendent selon qu'il s'agit d'une compression nerveuse, vasculaire ou vasculo-nerveuse. Le but de cette étude est de décrire certains aspects cliniques particuliers et évaluer le résultat fonctionnel après la décompression chirurgicale du paquet vasculo-nerveux. Notre étude rétrospective a porté sur l'analyse des données cliniques, radiologiques, IRM et EMG sur les patients opérés entre janvier 2010 et juillet 2013 du syndrome de défilé thoraco-brachial dans le service de traumatologie orthopédie de l'hôpital Ibn Sina de Rabat. 15 cas ont été colligés: 12 cas post traumatiques (fracture de la clavicule) et 3 cas d'origines congénitales, dont l’âge moyen était 35 ans (20 à 50 ans) avec 9 femmes et 6 hommes. A la fin du traitement, le score de Dash est passé de 109 (46% Normal=0) à 70 (20%), et le stress test de Roos était de 70/100 à 80/100. Le résultat était excellent dans 12 cas soit (80%) et moins bon dans dans 3 cas (20%). En définitive, la résection de malformations osseuses, l'excision des brides et la neurolyse du plexus brachial suivie de la rééducation a donné une bonne évolution fonctionnelle. PMID:25709735

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

2014-01-01

189

Thoracic outlet syndrome caused by schwannoma of brachial plexus.  

PubMed

Schwannomas are benign, usually slow-growing tumors that originate from Schwann cells surrounding peripheral, cranial, or autonomic nerves. The most common form of these tumors is acoustic neuroma. Schwannomas of the brachial plexus are quite rare, and symptomatic schwannomas of the brachial plexus are even rarer. A 47-year-old woman presented with a 1-year history of dysesthesia, neuropathic pain, and mild weakness of the right upper limb. Results of physical examination and electrodiagnostic studies supported a diagnosis as thoracic outlet syndrome. Conservative treatment did not relieve her symptoms. After 9 months, a soft mass was found at the upper margin of the right clavicle. Magnetic resonance imaging showed a 3.0×1.8×1.7 cm ovoid mass between the inferior trunk and the anterior division of the brachial plexus. Surgical mass excision and biopsy were performed. Pathological findings revealed the presence of schwannoma. After schwannoma removal, the right hand weakness did not progress any further and neuropathic pain gradually reduced. However, dysesthesia at the right C8 and T1 dermatome did not improve. PMID:24466527

Yun, Dong Hwan; Kim, Hee-Sang; Chon, Jinmann; Lee, Jongeon; Jung, Pil Kyo

2013-12-01

190

Thoracic Outlet Syndrome Caused by Schwannoma of Brachial Plexus  

PubMed Central

Schwannomas are benign, usually slow-growing tumors that originate from Schwann cells surrounding peripheral, cranial, or autonomic nerves. The most common form of these tumors is acoustic neuroma. Schwannomas of the brachial plexus are quite rare, and symptomatic schwannomas of the brachial plexus are even rarer. A 47-year-old woman presented with a 1-year history of dysesthesia, neuropathic pain, and mild weakness of the right upper limb. Results of physical examination and electrodiagnostic studies supported a diagnosis as thoracic outlet syndrome. Conservative treatment did not relieve her symptoms. After 9 months, a soft mass was found at the upper margin of the right clavicle. Magnetic resonance imaging showed a 3.0×1.8×1.7 cm ovoid mass between the inferior trunk and the anterior division of the brachial plexus. Surgical mass excision and biopsy were performed. Pathological findings revealed the presence of schwannoma. After schwannoma removal, the right hand weakness did not progress any further and neuropathic pain gradually reduced. However, dysesthesia at the right C8 and T1 dermatome did not improve. PMID:24466527

Yun, Dong Hwan; Kim, Hee-Sang; Chon, Jinmann; Jung, Pil Kyo

2013-01-01

191

Molecular responses of radiation-induced liver damage in rats.  

PubMed

The aim of the present study was to investigate the molecular responses involved in radiation?induced liver damage (RILD). Sprague?Dawley rats (6?weeks?old) were irradiated once at a dose of 20 Gy to the right upper quadrant of the abdomen. The rats were then sacrificed 3 days and 1, 2, 4, 8 and 12 weeks after irradiation and rats, which were not exposed to irradiation were used as controls. Weight measurements and blood was obtained from the rats and liver tissues were collected for histological and apoptotic analysis. Immunohistochemistry, reverse transcription quantitative polymerase chain reaction (RT?qPCR) and western blot analysis were performed to measure the expression levels of mRNAs and proteins, respectively. The serum levels of alanine aminotransferase, aspartate aminotransferase and alkaline phosphatase were increased significantly in the RILD rats. Histological investigation revealed the proliferation of collagen and the formation of fibrotic tissue 12 weeks after irradiation. Apoptotic cells were observed predominantly 2 and 4 weeks after irradiation. The immunohistochemistry, RT?qPCR and western blot analysis all revealed the same pattern of changes in the expression levels of the molecules assessed. The expression levels of transforming growth factor??1 (TGF??1), nuclear factor (NF)??B65, mothers against decapentaplegic homolog 3 (Smad3) and Smad7 and connective tissue growth factor were increased during the recovery period following irradiation up to 12 weeks. The expression levels of tumor necrosis factor??, Smad7 and Smad4 were only increased during the early phase (first 4 weeks) of recovery following irradiation. In the RILD rat model, the molecular responses indicated that the TGF??1/Smads and NF??B65 signaling pathways are involved in the mechanism of RILD recovery. PMID:25483171

Cheng, Wei; Xiao, Lei; Ainiwaer, Aimudula; Wang, Yunlian; Wu, Ge; Mao, Rui; Yang, Ying; Bao, Yongxing

2015-04-01

192

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

193

Molecular responses of radiation-induced liver damage in rats  

PubMed Central

The aim of the present study was to investigate the molecular responses involved in radiation-induced liver damage (RILD). Sprague-Dawley rats (6-weeks-old) were irradiated once at a dose of 20 Gy to the right upper quadrant of the abdomen. The rats were then sacrificed 3 days and 1, 2, 4, 8 and 12 weeks after irradiation and rats, which were not exposed to irradiation were used as controls. Weight measurements and blood was obtained from the rats and liver tissues were collected for histological and apoptotic analysis. Immunohistochemistry, reverse transcription quantitative polymerase chain reaction (RT-qPCR) and western blot analysis were performed to measure the expression levels of mRNAs and proteins, respectively. The serum levels of alanine aminotransferase, aspartate aminotransferase and alkaline phosphatase were increased significantly in the RILD rats. Histological investigation revealed the proliferation of collagen and the formation of fibrotic tissue 12 weeks after irradiation. Apoptotic cells were observed predominantly 2 and 4 weeks after irradiation. The immunohistochemistry, RT-qPCR and western blot analysis all revealed the same pattern of changes in the expression levels of the molecules assessed. The expression levels of transforming growth factor-?1 (TGF-?1), nuclear factor (NF)-?B65, mothers against decapentaplegic homolog 3 (Smad3) and Smad7 and connective tissue growth factor were increased during the recovery period following irradiation up to 12 weeks. The expression levels of tumor necrosis factor-?, Smad7 and Smad4 were only increased during the early phase (first 4 weeks) of recovery following irradiation. In the RILD rat model, the molecular responses indicated that the TGF-?1/Smads and NF-?B65 signaling pathways are involved in the mechanism of RILD recovery. PMID:25483171

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

2015-01-01

194

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

195

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.

196

?-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

197

Irradiated Esophageal Cells are Protected from Radiation-Induced Recombination by MnSOD Gene Therapy  

E-print Network

Radiation-induced DNA damage is a precursor to mutagenesis and cytotoxicity. During radiotherapy, exposure of healthy tissues can lead to severe side effects. We explored the potential of mitochondrial SOD (MnSOD) gene ...

Niu, Yunyun

198

Quantitative model of radiation induced charge trapping in SiO2  

Microsoft Academic Search

A predictive model of radiation induced oxide charging, thermodynamics and electron spin resonance measurements of defects known as E' centers, has been developed. The model is successfully tested on 60Co irradiated MOSFETs

P. M. Lenahan; B. D. Wallace; P. Cole

1997-01-01

199

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

Microsoft Academic Search

Results are presented showing the radiation response of several unhardened commercial 1.25-μm 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 δV{sub T} in the channel region is usually small at the failure dose. Time dependent leakage current data for the field oxides are presented

J. M. Terrell; T. R. Olkham; A. J. Lelis; J. M. Benedetto

1989-01-01

200

Modeling the anneal of radiation-induced trapped holes in a varying thermal environment  

Microsoft Academic Search

The anneal of radiation-induced trapped holes in MOS transistors is found to be thermally activated. A quantitative, physical model based on thermal emission and tunneling is developed. It accurately predicts the anneal of radiation-induced trapped holes in constant or time-varying thermal environments. Data are presented which quantitatively verify the accuracy of the model for temperatures between 25 and 160°C. This

P. J. McWhorter; S. L. Miller; W. M. Miller

1990-01-01

201

Ceramide Biogenesis Is Required for Radiation-Induced Apoptosis in the Germ Line of C. elegans  

Microsoft Academic Search

Ceramide engagement in apoptotic pathways has been a topic of controversy. To address this controversy, we tested loss-of-function (lf) mutants of conserved genes of sphingolipid metabolism in Caenorhabditis elegans. Although somatic (developmental) apoptosis was unaffected, ionizing radiation-induced apoptosis of germ cells was obliterated upon inactivation of ceramide synthase and restored upon microinjection of long-chain natural ceramide. Radiation-induced increase in the

Xinzhu Deng; Xianglei Yin; Richard Allan; Diane D. Lu; Carine W. Maurer; Adriana Haimovitz-Friedman; Zvi Fuks; Shai Shaham; Richard Kolesnick

2008-01-01

202

Application of Formaldehyde for Treatment of Hemorrhagic Radiation-Induced Proctitis  

Microsoft Academic Search

. Radiation-induced proctitis with hemorrhage is not a common complication of radiotherapy to the pelvis for carcinoma.\\u000a In the most severe forms, massive hemorrhage may necessitate repeated transfusions and inpatient treatment. In severe cases\\u000a medical treatment has not been proved effective. Surgery may lead to serious complications and is technically difficult. Six\\u000a patients who showed a hemorrhagic radiation-induced proctitis have

B. Roche; R. Chautems; M. C. Marti

1996-01-01

203

Arachidonic Acid Metabolites Mediate the Radiation-Induced Increase in Glomerular Albumin Permeability  

Microsoft Academic Search

Radiation-induced renal injury is characterized by proteinuria, hypertension, and progressive decline in renal function. We have previously shown that in vivo or in vitro irradiation of glomeruli with a single dose of radiation (9.5 Gy) increases glomerular albumin permeability (Palb) within 1 hr. The current studies tested the hypothesis that this early radiation-induced increase in Palb is caused by the

MUKUT SHARMA; ELLEN T. MCCARTHY; RAM SHARMA; BRIAN L. FISH; VIRGINIA J. SAVIN; ERIC P. COHEN; JOHN E. MOULDER

204

Effect of bias on radiation-induced paramagnetic defects at the silicon-silicon dioxide interface  

Microsoft Academic Search

Electron spin resonance measurements have been made on gamma-irradiated (111) Si\\/SiO2 structures as a function of bias across the oxide. We observe a large change in the density of radiation-induced paramagnetic Pb centers with bais. We conclude that Pb defects (trivalent silicons at the Si\\/SiO2 interface) account for a very large portion of the radiation-induced interface states.

P. M. Lenahan; P. V. Dressendorfer

1982-01-01

205

Idiopathic and Radiation-Induced Ocular Telangiectasia: The Involvement of the ATM Gene  

Microsoft Academic Search

PURPOSE. To investigate whether individuals, with no family history of ataxia telangiectasia (AT), in whom idiopathic or radiation-induced ocular telangiectasia developed are carriers of ATM gene mutations. METHODS. The ATM cDNA from lymphoblastoid cell lines estab- lished from 16 patients with idiopathic retinal or choroidal telan- giectasia and 14 patients with radiation-induced telangiectasia after radiotherapy for age-related macular degeneration (AMD)

Martine Mauget-Faysse; Michele Vuillaume; Maddalena Quaranta; Norman Moullan; Sandra Angele; Marlin D. Friesen; Janet Hall

2003-01-01

206

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

207

Targets for, and consequences of, radiation-induced chromosomal instability  

NASA Astrophysics Data System (ADS)

Chromosomal instability has been demonstrated in a human- hamster hybrid cell line, GM10115, after exposure to x- rays. Chromosomal instability in these cells is characterized by the appearance of novel chromosomal rearrangements multiple generations after exposure to ionizing radiation. To identify the cellular target(s) for radiation-induced chromosomal instability, cells were treated with 125I-labeled compounds. Labeling cells with 125I-iododeoxyuridine, which caused radiation damage to the DNA and associated nuclear structures, did induce chromosomal instability. While cell killing and first-division chromosomal rearrangements increased with increasing numbers of 125I decays, the frequency of chromosomal instability was independent of dose. Incorporation of an 125I-labeled protein, 125I-succinyl- concanavalin A, into either the plasma membrane or the cytoplasm, failed to elicit chromosomal instability. These results show that radiation damage to the nucleus, and not to extranuclear regions, contributes to the induction of chromosomal instability. To determine the role of DNA strand breaks as a molecular lesion responsible for initiating chromosomal instability, cells were treated with a variety of DNA strand breaking agents. Agents capable of producing complex DNA double strand breaks, including X-rays, Neocarzinostatin and bleomycin, were able to induce chromosomal instability. In contrast, double strand breaks produced by restriction endonucleases as well as DNA strand breaks produced by hydrogen peroxide failed to induce chromosomal instability. This demonstrates that the type of DNA breakage is important in the eventual manifestation of chromosomal instability. In order to understand the relationship between chromosomal instability and other end points of genomic instability, chromosomally stable and unstable clones were analyzed for sister chromatid exchange, delayed reproductive cell death, delayed mutation, mismatch repair and delayed gene amplification. Although individual clones within each group were significantly different from unirradiated clones for many of the endpoints, there was no significant correlation between chromosomal instability and the phenotypes of sister chromatid exchange, delayed mutation, and mismatch repair. Delayed gene amplification weakly correlated chromosomal instability (0.05 < p < 0.1) and delayed reproductive cell death correlated strongly (p < 0.05) with chromosomal instability. These data indicate that multiple pathways exist for inducing genomic instability in GM10115 cells after radiation exposure.

Kaplan, Mark Isaac

208

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

209

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

PubMed Central

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

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

2014-01-01

210

Spinal Anesthesia as a Complication of Brachial Plexus Block Using the Posterior Approach  

Microsoft Academic Search

or surgical procedures of the upper extremities, the brachial plexus block is a suitable technique and offers several advantages for the patient, sur- geon, and anesthesiologist (1). The brachial plexus block can be performed at several sites, but the most frequently used are the axillary, interscalene, infracla- vicular, and supraclavicular approaches (2). Pippa et al. (3) described an alternative, posterior

Majid Aramideh; Huub L. A. van den Oever; Gerard J. Walstra; Misa Dzoljic

2002-01-01

211

Structure of the brachial plexus root and adjacent regions displayed by ultrasound imaging?  

PubMed Central

Brachial plexuses of 110 healthy volunteers were examined using high resolution color Doppler ultrasound. Ultrasonic characteristics and anatomic variation in the intervertebral foramen, interscalene, supraclavicular and infraclavicular, as well as the axillary brachial plexus were investigated. Results confirmed that the normal brachial plexus on cross section exhibited round or elliptic hypoechoic texture. Longitudinal section imaging showed many parallel linear hypo-moderate echoes, with hypo-echo. The transverse processes of the seventh cervical vertebra, the scalene space, the subclavian artery and the deep cervical artery are important markers in an examination. The display rates for the interscalene, and supraclavicular and axillary brachial plexuses were 100% each, while that for the infraclavicular brachial plexus was 97%. The region where the normal brachial plexus root traversed the intervertebral foramen exhibited a regular hypo-echo. The display rate for the C5-7 nerve roots was 100%, while those for C8 and T1 were 83% and 68%, respectively. A total of 20 of the 110 subjects underwent cervical CT scan. High-frequency ultrasound can clearly display the outline of the transverse processes of the vertebrae, which were consistent with CT results. These results indicate that high-frequency ultrasound provides a new method for observing the morphology of the brachial plexus. The C7 vertebra is a marker for identifying the position of brachial plexus nerve roots. PMID:25624836

Li, Zhengyi; Xia, Xun; Rong, Xiaoming; Tang, Yamei; Xu, Dachuan

2012-01-01

212

Brachial plexus palsy associated with cesarean section: An in utero injury?  

Microsoft Academic Search

Objective: Brachial plexus injury may be unrelated to manipulations performed at the time of delivery, occurring in the absence of shoulder dystocia and in the posterior arm of infants with anterior shoulder dystocia. To further support the hypothesis that some of these nerve injuries appear to be of intrauterine origin, we present a series of brachial plexus palsies associated with

Robert B. Gherman; T. Murphy Goodwin; Joseph G. Ouzounian; David A. Miller; Richard H. Paul

1997-01-01

213

Penile erectile dysfunction after brachial plexus root avulsion injury in rats  

PubMed Central

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

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

2014-01-01

214

Continuous axillary brachial plexus analgesia in a patient with severe hemophilia.  

PubMed

Until now, the safety of continuous axillary brachial plexus block in a patient with hemophilia has not been reported. We describe the use of continuous axillary brachial plexus block for postoperative pain control in a patient with severe hemophilia after an elbow surgery. PMID:12693408

Kang, Seuk B; Rumball, Kevin M; Ettinger, Robert S

2003-02-01

215

Large brachial and common carotid artery diameter in postmenopausal women with carotid atherosclerosis  

Microsoft Academic Search

Background and purpose: It is recognized that arteries can enlarge to compensate atherosclerosis. The role of diameter enlargement of unaffected arteries is not well known. We hypothesized that brachial and common carotid arteries diameters were larger in subjects with carotid atherosclerosis compared to subjects without these lesions. 12 13 14 Methods: We measured diameters in the common carotid and brachial

Tiziana Montalcini; Gaetano Gorgone; Carmine Gazzaruso; Giorgio Sesti; Francesco Perticone; Arturo Pujia

216

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

PubMed Central

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

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

2014-01-01

217

DOES BRACHIAL ARTERY FMD PROVIDE A BIOASSAY FOR NITRIC OXIDE?  

PubMed Central

This study sought to better define the role of nitric oxide (NO) in brachial artery flow-mediated vasodilation (FMD) in young, healthy humans. Brachial artery blood velocity and diameter were determined (ultrasound Doppler) in eight volunteers (26 ± 1 yrs) before and after 5-min forearm circulatory occlusion with and without intra-arterial infusion of the endothelial nitric oxide synthase (eNOS) inhibitor L-NMMA (0.48 mg/dl/min). Control (CON) and L-NMMA trials were performed with the occlusion cuff placed in the traditional distal position, as well as proximal to the measurement site. FMD was significantly reduced, but not abolished, by L-NMMA in the distal cuff trial (8.9 ± 1.3 to 6.0 ± 0.7%, CON vs. L-NMMA, P = 0.02), with no effect of L-NMMA on FMD with proximal cuff placement (10.6 ± 1.2 to 12.4 ± 1.7%, CON vs. L-NMMA, P = 0.39). When the reduction in shear stimulus following L-NMMA was taken into account, no drug difference was observed for either distal (0.26 ± 0.02 to 0.23 ± 0.03, CON vs. L-NMMA, P = 0.40) or proximal (0.23 ± 0.08 to 0.23 ± 0.03, CON vs. L-NMMA, P = 0.89) FMD trials. These findings challenge the assertion that NO is obligatory for brachial artery FMD, and call into question the sensitivity of this procedure for non-invasive determination of NO bioavailability in young, healthy humans. PMID:23774225

Wray, D. Walter; Witman, Melissa A. H.; Ives, Stephen J.; McDaniel, John; Trinity, Joel D.; Conklin, Jamie D.; Supiano, Mark A.; Richardson, Russell S.

2013-01-01

218

The protective effect of brachial plexus palsy in purpura fulminans.  

PubMed

Acute infectious purpura fulminans is reported in a 16-month-old male with a history of posttraumatic asplenia and complete left brachial plexus palsy. This patient developed peripheral necrosis of both lower extremities and the right upper extremity, whereas the left upper extremity was completely spared from ischemia and tissue damage. Amputation of four digits on the right hand and debridement of both lower extremities were required. This patient demonstrated the protective effect of a traumatic sympathectomy, which suggests the requirement of an intact sympathetic reflex in the development of purpura fulminans. PMID:11516614

Willis, T M; Hopp, R J; Romero, J R; Larsen, P D

2001-05-01

219

Miliary tuberculosis with left brachial monoplegia: A case report.  

PubMed

Tuberculoma of the brain is a major neurological problem in developing countries accounting for 12 to 30 per cent of all intracranial masses. It often presents with focal neurological symptoms or seizures. Simultaneous occurrence of brain tuberculoma with miliary mottling in the lungs is uncommon in the immunocompetent patient. We report only the second case of monoplegia and miliary tuberculosis, wherein the patient presented with acute onset left brachial monoplegia, upper motor neuron facial palsy, and fever with an MRI of the brain showing multiple granulomas and chest x-ray showing miliary mottling. The patient's neurological deficit started to resolve with corticosteroids and anti-tubercular treatment. PMID:25379061

Iqbal, Nayyar; Natarajan, Nagarajan; Periyasamy, Sivakumar; George, Sanjoy; Basheer, Aneesh; Mookkappan, Sudhagar

2014-01-01

220

In Utero Causation of Brachial Plexus Injury: Myth or Mystery?  

Microsoft Academic Search

\\u000a \\u000a In utero causation is a manufactured theory based on speculation that contradicts known anatomic and physiologic principles. Brachial\\u000a plexus injury (BPI) is a very-low-velocity and very-low-impact injury. Adult BPI is a high-velocity and high-impact injury.\\u000a Labor forces are compressive and expulsive, not traction or stretching. “Using a statistical model it is possible to identify\\u000a adverse combinations of factors that are

James A. O’Leary

221

Delayed bilateral spinal anaesthesia following interscalene brachial plexus block  

Microsoft Academic Search

Purpose  To present a case of delayed neuraxial blockade after interscalene brachial plexus block.\\u000a \\u000a \\u000a \\u000a Clinical features  A 65-yr-old lady presenting for radial head excision underwent a right interscalene block using bupivacaine and lidocaine.\\u000a She experienced excellent anaesthesia and had stable vital signs for the duration of surgery. However, after 65 min, she developed\\u000a signs of bilateral neuraxial block, progressing over the following

Desmond Norris; Andrew Klahsen; Brian Milne

1996-01-01

222

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

223

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

PubMed

Radiation-induced DNA damage is a precursor to mutagenesis and cytotoxicity. During radiotherapy, exposure of healthy tissues can lead to severe side effects. We explored the potential of mitochondrial SOD (MnSOD) gene therapy to protect esophageal, pancreatic and bone marrow cells from radiation-induced genomic instability. Specifically, we measured the frequency of homologous recombination (HR) at an integrated transgene in the Fluorescent Yellow Direct Repeat (FYDR) mice, in which an HR event can give rise to a fluorescent signal. Mitochondrial SOD plasmid/liposome complex (MnSOD-PL) was administered to esophageal cells 24 h prior to 29 Gy upper-body irradiation. Single cell suspensions from FYDR, positive control FYDR-REC, and negative control C57BL/6NHsd (wild-type) mouse esophagus, pancreas and bone marrow were evaluated by flow cytometry. Radiation induced a statistically significant increase in HR 7 days after irradiation compared to unirradiated FYDR mice. MnSOD-PL significantly reduced the induction of HR by radiation at day 7 and also reduced the level of HR in the pancreas. Irradiation of the femur and tibial marrow with 8 Gy also induced a significant increase in HR at 7 days. Radioprotection by intraesophageal administration of MnSOD-PL was correlated with a reduced level of radiation-induced HR in esophageal cells. These results demonstrate the efficacy of MnSOD-PL for suppressing radiation-induced HR in vivo. PMID:20334517

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

2010-04-01

224

Traumatic Pseudoaneurysm of Axillary Artery Combined with Brachial Plexus Injury  

PubMed Central

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

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

2014-01-01

225

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

PubMed Central

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

2014-01-01

226

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

227

Inter-chromosomal heterogeneity in the formation of radiation induced chromosomal aberrations  

SciTech Connect

it is generally assumed that radiation induced chromosomal lesions are distributed randomly and repaired randomly among the genome. Recent studies using fluorescent in situ hybridization (FISH) and chromosome specific DNA libraries indicate that some chromosomes are more sensitive for radiation induced aberration formation than others. Chromosome No. 4 in human and chromosome No. 8 in Chinese hamster have been found to involve more in exchange aberrations than others, when calculated on the basis of their DNA content. Painting with arm specific chromosome libraries indicate that the frequencies of radiation induced intra-chromosome exchanges (i.e., between the arms of a chromosome, such as centric rings and inversions) are far in excess than one would expect on the basis of the frequencies of observed inter-chromosomal exchanges. The possible factors leading to the observed heterogeneity will be discussed.

Natarajan, A.T.; Vermeulen, S.; Boei, J.J.W.A. [Leiden Univ. (Netherlands)

1997-10-01

228

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

SciTech Connect

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

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

1988-01-01

229

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

230

The Radiation-Induced Formation of Excited States of Aromatic Hydrocarbons in Benzene and Cyclohexane. I. Radiation Induced Fluorescence from Solutions of Aromatic Hydrocarbons in Cyclohexane  

Microsoft Academic Search

The nature of radiation-induced fluorescence from solutions of anthracene, naphthalene and pyrene in cyclohexane has been investigated. Evidence is presented for the formation of excited singlet solute molecules via charge recombination processes. Rate constants, measured by the pulse radiolysis technique, are reported for the quenching of excited singlet state molecules of naphthalene and pyrene by oxygen, xenon, iodine, 1,3-cyclohexadiene, nitrous

E. L. Frankevich; T. Morrow; G. A. Salmon

1972-01-01

231

Methylglyoxal-bis(guanylhydrazone), a polyamine analogue, sensitized ?-radiation-induced cell death in HL-60 leukemia cells Sensitizing effect of MGBG on ?-radiation-induced cell death.  

PubMed

Methylglyoxal-bis(guanylhydrazone) (MGBG), a polyamine analogue, has been known to inhibit the biosynthesis of polyamines, which are important in cell proliferation. We showed that MGBG treatment significantly affected ?-radiation-induced cell cycle transition (G(1)/G(0)?S?G(2)/M) and thus ?-radiation-induced cell death. As determined by micronuclei and comet assay, we showed that it sensitized the cytotoxic effect induced by ?-radiation. One of the reasons is that polyamine depletion by MGBG treatment did not effectively protect against the chemical (OH) or physical damage to DNA caused by ?-radiation. Through in vitro experiment, we confirmed that DNA strand breaks induced by ?-radiation was prevented more effectively in the presence of polyamines (spermine and spermidine) than in the absence of polyamines. MGBG also blocks the cell cycle transition caused by ?-radiation (G(2) arrest), which helps protect cells by allowing time for DNA repair before entry into mitosis or apoptosis, via the down regulation of cyclin D1, which mediates the transition from G(1) to S phase of cell cycle, and ataxia telangiectasia mutated, which is involved in the DNA sensing, repair and cell cycle check point. Therefore, the abrogation of G(2) arrest sensitizes cells to the effect of ?-radiation. As a result, ?-radiation-induced cell death increased by about 2.5-3.0-fold in cells treated with MGBG. However, exogenous spermidine supplement partially relieved this ?-radiation-induced cytotoxicity and cell death. These findings suggest a potentially therapeutic strategy for increasing the cytotoxic efficacy of ?-radiation. PMID:21783704

Kim, Jin Sik; Lee, Jin; Chung, Hai Won; Choi, Han; Paik, Sang Gi; Kim, In Gyu

2006-09-01

232

[Ipsilateral brachial plexus C7 root transfer. Presentation of a case and a literature review].  

PubMed

The C7 root in brachial plexus injuries has been used since 1986, since the first description by Gu at that time. This root can be used completely or partially in ipsilateral or contralateral lesions of the brachial plexus. A review of the literature and the case report of a 21-month-old girl with stab wounds to the neck and section of the C5 root of the right brachial plexus are presented. A transfer of the anterior fibres of the ipsilateral C7 root was performed. At 9 months there was complete recovery of abduction and external rotation of the shoulder. PMID:23474130

Vergara-Amador, Enrique; Ramírez, Alejandro

2014-01-01

233

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

234

Macro-Bending Influence on Radiation Induced Attenuation Measurement in Optical Fibres  

E-print Network

Influence of the bending radius on the measurement of radiation induced attenuation in glass optical fibres is discussed in this paper. Radiation induced attenuation measured in two single-mode fibre types shows discrepancies when coiled around a low bending radius spool: the observed attenuation is lower than expected. A series of dedicated tests reveals that this invalid measurement is related to the displacement of the mode field towards the cladding when the fibre is bent with a low radius, and to the different radiation resistances of the core and cladding glasses. For irradiation tests of optical fibres, the spool radius should therefore be carefully chosen.

Guillermain, E; Ricci, D; Weinand, U

2014-01-01

235

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

236

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

PubMed

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

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

2014-09-15

237

Utility of automated brachial ankle pulse wave velocity measurements in hypertensive patients  

Microsoft Academic Search

BackgroundWe examined whether pulse wave velocity (PWV), determined by brachial ankle arterial pressure wave measurements, using a newly developed, fully automated device could be a surrogate measure for carotid femoral PWV.

Masanori Munakata; Nobuhiko Ito; Tohru Nunokawa; Kaoru Yoshinaga

2003-01-01

238

Anatomical structure of the brachial plexus in the merlin (Falco columbarius).  

PubMed

This study aimed to document the detailed features of the morphological structure and the innervation areas of the brachial plexus in Merlin (Falco columbarius). The skin and muscles of five adult male Merlins were dissected under the stereo microscope. The Merlin had two plexus trunks. The accessory brachial plexus consisted of ventral rami C10 and C11. C11 was divided into two branches: the cranial and caudal. The brachial plexus was composed of a rather complex network involving the ventral rami of C11-C13, T1 and T2. In addition, a thin branch from the last two cervical sympathetic nerves participated in the plexus formation. C12, C13 and T1 had rather thick trunk. C12, C13 and T1 were also involved in the formation of the brachial plexus emerging after 1 cm from the foramen inter-vertebrale as three trunk roots. PMID:23464686

Çevik-Demirkan, A

2014-02-01

239

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

PubMed Central

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

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

2014-01-01

240

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. PMID:23661959

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

2013-01-01

241

Electronic Structure Theory of Radiation-Induced Defects in Si/SiO2 Andrew C. Pineda  

E-print Network

in amorphous silicon dioxide (a-SiO2) of what are collectively known as E' centers. These centers all appear1 Electronic Structure Theory of Radiation-Induced Defects in Si/SiO2 Andrew C. Pineda and Shashi P Aberdeen Ave, SE, Bldg. 914, Kirtland AFB, NM 87117-5776 ABSTRACT Radiation-induced defects in metal

242

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

SciTech Connect

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

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

2013-10-01

243

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

NASA Technical Reports Server (NTRS)

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

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

2001-01-01

244

A model of radiation induced leakage current (RILC) in ultra-thin gate oxides  

Microsoft Academic Search

An analytical model of Radiation Induced Leakage Current (RILC) has been developed for ultra-thin gate oxides submitted to high dose ionizing radiation. The model is based on the solution of the Schrodinger equation for a simplified oxide band structure, where RILC occurs through electron trap-assisted tunneling. The values of the model parameters have been calibrated by comparing the transmission probabilities

L. Larcher; A. Paccagnella; M. Ceschia; G. Ghidini

1999-01-01

245

Ionizing radiation induced leakage current on ultra-thin gate oxides  

Microsoft Academic Search

MOS capacitors with a 4.4 nm thick gate oxide have been exposed to ? radiation from a Co60 source. As a result, we have measured a stable leakage current at fields lower than those required for Fowler-Nordheim tunneling. This Radiation Induced Leakage Current (RILC) is similar to the usual Stress Induced Leakage Currents (SILC) observed after electrical stresses of MOS

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

1997-01-01

246

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

Microsoft Academic Search

Low-field leakage current has been measured in thin oxides after exposure to ionising radiation. This Radiation Induced Leakage Current (RILC) can be described as an inelastic tunnelling process mediated by neutral traps in the oxide, with an energy loss of about 1 eV. The neutral trap distribution is influenced by the oxide field applied during irradiation, thus indicating that the

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

1998-01-01

247

Experimental Study on Radiation Induced Boiling Enhancement for Stainless Steel Plate  

SciTech Connect

The Radiation Induced Boiling Enhancement phenomena (RIBE) were confirmed using the SUS304 foil. The SUS304 with plasma oxidized surface shows higher CHF, i.e., about 20% improvement. While, the natural and mixed gas oxidized surface does not show the boiling enhancement. The RIBE has been highly related to the surface conditions. (authors)

Koji Okamoto; Hiroshi Akiyama; Haruki Madarame [University of Tokyo (Japan); Tomoji Takamasa [Tokyo University of Mercantile Marine, 2-1-6 Etchu-jima, Koto-Ku, Tokyo 135-8533 (Japan)

2002-07-01

248

Cytogenetic Changes in Radiation-induced Tumors of the Thyroid1  

Microsoft Academic Search

Thyroid carcinoma incidence is increased significantly after ionizing irradiation; however, the possible mechanisms have not yet been identi- fied. To provide clues for an understanding of the radiation-induced transformation of thyroid epithelium, we analyzed the karyotypes of 56 childhood thyroid tumors that appeared in Belarus after the Chernobyl nuclear accident in 1986. We also studied eight secondary thyroid tumors that

Horst Zitzelsberger; Lars Lehmann; Ludwig Hieber; Heinz-Ulrich G. Weier; Catherine Janish; Jingly Fung; Thomas Negele; Fritz Spelsberg; Edmund Lengfelder; Eugene P. Demidchik; Konstatinos Salassidis; Albrecht M. Kellerer; Martin Werner; Manfred Bauchinger

1992-01-01

249

Radiation-Induced Apoptosis Varies Among Individuals and is Modified by Sex and Age  

PubMed Central

Purpose Although there are considerable data on mechanisms of radiation-induced apoptosis in vitro and in animal models, little is known about functional variation in these pathways in humans. We sought to develop a tractable system to evaluate this. Materials and methods Peripheral blood mononuclear cells were isolated from 90 healthy volunteers, divided into two aliquots, one irradiated with a 5 Gy dose and the other sham-treated (0 Gy), and assessed for damage-induced apoptosis after 24 hours. To investigate reproducibility, ten individuals spanning the entire radiation-induced apoptotic range were tested three times each, with 3–6 months between replicates. Results We observed surprising heterogeneity in apoptosis among individuals, ranging from 21–62%. Biological replicates from a single individual, however, were completely concordant, suggesting the variability observed across individuals is not the result of stochastic or short-term effects. We found significantly higher radiation-induced apoptosis in males than in females (Mean: 41.0% vs. 30.7%; p < 3.5 × 10?7). Moreover, advancing age was associated with decreasing radiation-induced apoptosis in males (p = 0.01) but not females (p = 0.82).a Conclusions Our results provide evidence that the function of cellular pathways crucial for stress-induced apoptosis varies by sex and could decline with age in humans. PMID:24882388

Applebaum, Mark A.; Skol, Andrew D.; Bond, Elisabeth E.; Overholtzer, Michael; Bond, Gareth L.; Onel, Kenan

2014-01-01

250

Development of an in vitro model for radiation-induced effects on oral keratinocytes  

Microsoft Academic Search

Changes in epithelial cell activity and the production of pro-inflammatory cytokines were examined utilizing an organotypic culture system as an in vitro model to study the effects of radiation on oral keratinocytes to simulate what is thought to occur in radiation-induced oral mucositis. Monolayer cultures of oral keratinocyte were irradiated by varying the dose. Cell injury was assessed using a

T. Tobita; K. Izumi; S. E. Feinberg

2010-01-01

251

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. PMID:23969972

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

2013-01-01

252

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

253

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

SciTech Connect

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

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

1987-06-01

254

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

SciTech Connect

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

Boomsma, Marjolein J.; Bijl, Hendrik P.; Christianen, Miranda E.M.C.; Beetz, Ivo; Chouvalova, Olga; Steenbakkers, Roel J.H.M. [Department of Radiation Oncology, University Medical Center Groningen, University of Groningen, Groningen (Netherlands); Laan, Bernard F.A.M. van der [Department of Otorhinolaryngology/Head and Neck Surgery, University Medical Center Groningen, University of Groningen, Groningen (Netherlands); Wolffenbuttel, Bruce H.R. [Department of Endocrinology, University Medical Center Groningen, University of Groningen, Groningen (Netherlands)] [Department of Endocrinology, University Medical Center Groningen, University of Groningen, Groningen (Netherlands); Oosting, Sjoukje F. [Department of Medical Oncology, University Medical Center Groningen, University of Groningen, Groningen (Netherlands)] [Department of Medical Oncology, University Medical Center Groningen, University of Groningen, Groningen (Netherlands); Schilstra, Cornelis [Department of Radiation Oncology, University Medical Center Groningen, University of Groningen, Groningen (Netherlands)] [Department of Radiation Oncology, University Medical Center Groningen, University of Groningen, Groningen (Netherlands); Langendijk, Johannes A., E-mail: j.a.langendijk@umcg.nl [Department of Radiation Oncology, University Medical Center Groningen, University of Groningen, Groningen (Netherlands)

2012-11-01

255

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

SciTech Connect

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

Partington, M.D.; Davis, D.H. (Mayo Clinic, Rochester, MN (USA))

1990-02-01

256

Naringin, a citrus flavonone, protects against radiation-induced chromosome damage in mouse bone marrow  

Microsoft Academic Search

Free radicals are responsible for the induction of damage to the cellular DNA that leads to the formation of chromosome aberrations. Antioxidants are known to scavenge free rad- icals, thereby decreasing the degree of such effects. Radi- ation is a well-known inducer of free radicals and compounds that can scavenge free radicals may reduce radiation-induced DNA damage. Naringin, a bioflavonoid

Ganesh Chandra Jagetia; V. A. Venkatesh; Tiyyagura Koti Reddy

2003-01-01

257

Repression of ATR pathway by miR-185 enhances radiation-induced apoptosis and proliferation  

E-print Network

OPEN Repression of ATR pathway by miR-185 enhances radiation-induced apoptosis and proliferation of a human microRNA (miRNA), hsa-miR-185, is downregulated in response to ionizing radiation. Elevation of miR damage and DNA replication stresses, is a target of miR-185. This prediction was validated by luciferase

Cai, Long

258

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

SciTech Connect

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

Yannam, Govardhana Rao [Department of Surgery, University of Nebraska Medical Center, Omaha, Nebraska (United States); Han, Bing [Department of Surgery, University of Pittsburgh, Pittsburgh, Pennsylvania (United States); Department of Hepatobiliary Surgery, First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, Shaanxi (China); Setoyama, Kentaro [Department of Surgery, University of Pittsburgh, Pittsburgh, Pennsylvania (United States); Yamamoto, Toshiyuki [Department of Surgery, University of Nebraska Medical Center, Omaha, Nebraska (United States); Ito, Ryotaro; Brooks, Jenna M. [Department of Surgery, University of Pittsburgh, Pittsburgh, Pennsylvania (United States); Guzman-Lepe, Jorge [Department of Surgery, University of Pittsburgh, Pittsburgh, Pennsylvania (United States); Department of Pathology, Children's Hospital of Pittsburgh, Pittsburgh, Pennsylvania (United States); Galambos, Csaba [Department of Pathology, Children's Hospital of Pittsburgh, Pittsburgh, Pennsylvania (United States); Fong, Jason V. [Department of Surgery, University of Pittsburgh, Pittsburgh, Pennsylvania (United States); Deutsch, Melvin; Quader, Mubina A. [Department of Radiation Oncology, Children's Hospital of Pittsburgh, Pittsburgh, Pennsylvania (United States); Yamanouchi, Kosho [Department of Radiation Oncology, Albert Einstein College of Medicine, Bronx, New York (United States); Marion Bessin Liver Research Center, Albert Einstein College of Medicine, Bronx, New York (United States); Kabarriti, Rafi; Mehta, Keyur [Department of Radiation Oncology, Albert Einstein College of Medicine, Bronx, New York (United States); Soto-Gutierrez, Alejandro [Department of Pathology, Children's Hospital of Pittsburgh, Pittsburgh, Pennsylvania (United States); McGowan Institute for Regenerative Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania (United States); and others

2014-02-01

259

Measurements of the Radiation Induced Conductivity of Insulating Polymeric Materials for the James Webb Space Telescope  

Microsoft Academic Search

We report on initial measurements of Radiation Induced Conductivity (RIC) for twelve thin film polymer materials that are used in the cabling of the James Webb Space Telescope. Results will be used to model possible detrimental arching due to space craft charging effects. RIC occurs when incident ionizing radiation deposits energy in a material and excites electrons into the conduction

J. Corbridge; J. R. Dennison; J. Hodges; R. C. Hoffmann; J. Abbott; A. Hunt; R. Spaulding

2006-01-01

260

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

EPA Science Inventory

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

261

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

EPA Science Inventory

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

262

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

263

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

264

Pressure-sensitive blackbody point radiation induced by infrared diode laser irradiation  

E-print Network

Pressure-sensitive blackbody point radiation induced by infrared diode laser irradiation Feng Qin,1 Ultrabroadband radiation from Yb2O3 at ambient and low air pressures was investigated under the excitation to environmental air pressure in the way that the integrated radiation intensity decreases linearly with increasing

Cao, Wenwu

265

Preparation of amidoxime-fiber adsorbents by radiation-induced grafting  

NASA Astrophysics Data System (ADS)

The fibrous adsorbents containing amidoxime groups were synthesized by radiation-induced graft polymerization of acrylonitrile onto polypropylene fibers, followed by functionalization of cyano groups to amidoxime groups with hydroxylamine. The polypropylene-based fibrous adsorbents exhibited a high grafting rate. The adsorption tests proved the performance of these fibrous adsorbents as a promising material for uranium recovery from seawater.

Kabay, Nalan; Katakai, Akio; Sugo, Takanobu

1995-02-01

266

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. PMID:21657969

2011-01-01

267

Complications of microsurgical reconstruction of obstetrical brachial plexus palsy.  

PubMed

The charts of the 173 consecutive patients who underwent microsurgical reconstruction for obstetrical brachial plexus palsy from 1988 to 1999 (inclusive) in the Division of Plastic Surgery at the Hospital for Sick Children were analyzed. The overall complication rate was 33.5 percent, and there was no mortality in this series. The most significant intraoperative complication was accidental extubation, which occurred five times in the first 84 patients (6 percent of this early group; 2.9 percent of the whole series). This complication was addressed by suturing the endotracheal tube to the membranous septum and by using a transparent drape to allow direct visualization of the tube in all 89 subsequent patients. There have been no further accidental extubations. Postoperative fluid overload occurred in 14 patients (8.1 percent), three (1.7 percent) of whom developed pulmonary edema. Intensive care unit admission was required in two of those patients. Diuretic treatment was required in seven patients. No patient receiving less than or equal to 4 ml/kg/hour developed fluid overload, whereas 50 percent of the patients receiving greater than or equal to 10 ml/kg/hour did. Currently, the authors' policy is to strictly limit intravenous maintenance fluids to 4 ml/kg/hour or less. Despite the long and complex procedure required to reconstruct obstetrical brachial plexus palsy, the incidence of significant complications can be minimized with simple precautions, such as suturing the endotracheal tube to the septum or reducing the amount of fluids administered during the operation. PMID:12618596

La Scala, Giorgio C; Rice, Sean B; Clarke, Howard M

2003-04-01

268

Clinical Effects of Capacitive Electric Transfer Hyperthermia Therapy for Cervico-Omo-Brachial Pain  

Microsoft Academic Search

We conducted physical therapy for patients suffering from cervico-omo-brachial pain (n=22) with high frequency hyperthermia equipment by a capacitive electric transfer method, MD-303 (0.65 ± 0.05 MHz), which is employed in Europe and America. The 22 patients comprised 6 with cervical spondylosis deformans, 6 with cervico-omo-brachial pain syndrome, 4 with periarthritis scapulohumeralis, 3 with cervical sprain, 2 with tennis elbow,

Kuniyasu Takahashi; Tetsuo Suyama; Yasuyuki Takakura; Shigeru Hirabayashi; Nobuyuki Tsuzuki; Zhong-Shi Li

2000-01-01

269

Inflammation predicts accelerated brachial arterial wall changes in patients with recent-onset rheumatoid arthritis  

Microsoft Academic Search

INTRODUCTION: Patients with recent-onset rheumatoid arthritis (RA) have impaired brachial artery endothelial function compared with controls matched for age, sex and cardiovascular risk factors. The present study examined endothelium-dependent (flow-mediated dilatation (FMD)) and independent (glyceryl trinitrate (GTN)-mediated dilatation (GMD)) structural responses in early RA patients, and determined progress over one year. METHODS: Brachial artery FMD and GMD and carotid intima

Suad Hannawi; Thomas H Marwick; Ranjeny Thomas

2009-01-01

270

Role of intraoperative neurophysiology in primary surgery for obstetrical brachial plexus palsy (OBPP)  

Microsoft Academic Search

Objective  Management of conducting neuroma-in-continuity in primary surgery for obstetrical brachial plexus palsy (OBPP) is still discussed controversially. We present our experience with intraoperative neurophysiological recordings in the management of lesions in continuity in OBPP.Methods  A series of ten children with lesions in continuity of the upper brachial plexus is presented. Due to recordable compound nerve action potentials (CNAPs) and muscle response

Ralph W. König; Gregor Antoniadis; Wolfgang Börm; Hans-Peter Richter; Thomas Kretschmer

2006-01-01

271

Color Doppler Ultrasound-guided Supraclavicular Brachial Plexus Block to Prevent Vascular Injection.  

PubMed

Ultrasound-guided nerve blocks are quickly becoming integrated into emergency medicine practice for pain control and as an alternative to procedural sedation. Common, but potentially catastophic errors have not been reported outside of the anesthesiology literature. Evaluation of the brachial plexus with color Doppler should be standard for clinicians performing a supraclavicular brachial plexus block to determine ideal block location and prevention of inadvertant intravascular injection. PMID:25247047

Hahn, Christopher; Nagdev, Arun

2014-09-01

272

Color Doppler Ultrasound-guided Supraclavicular Brachial Plexus Block to Prevent Vascular Injection  

PubMed Central

Ultrasound-guided nerve blocks are quickly becoming integrated into emergency medicine practice for pain control and as an alternative to procedural sedation. Common, but potentially catastophic errors have not been reported outside of the anesthesiology literature. Evaluation of the brachial plexus with color Doppler should be standard for clinicians performing a supraclavicular brachial plexus block to determine ideal block location and prevention of inadvertant intravascular injection. PMID:25247047

Hahn, Christopher; Nagdev, Arun

2014-01-01

273

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

PubMed Central

Radiation therapy is a common treatment for cancer patients. One of the most common side effects of radiation is acute skin reaction (radiation dermatitis) that ranges from a mild rash to severe ulceration. Approximately 85% of patients treated with radiation therapy will experience a moderate-to-severe skin reaction. Acute radiation-induced skin reactions often lead to itching and pain, delays in treatment, and diminished aesthetic appearance—and subsequently to a decrease in quality of life. Surveys have demonstrated that a wide variety of topical, oral, and intravenous agents are used to prevent or to treat radiation-induced skin reactions. We conducted a literature review to identify trials that investigated products for the prophylaxis and management of acute radiation dermatitis. Thirty-nine studies met the pre-defined criteria, with thirty-three being categorized as prophylactic trials and six as management trials. For objective evaluation of skin reactions, the Radiation Therapy Oncology Group criteria and the U.S. National Cancer Institute Common Toxicity Criteria were the most commonly used tools (65% of the studies). Topical corticosteroid agents were found to significantly reduce the severity of skin reactions; however, the trials of corticosteroids evaluated various agents, and no clear indication about a preferred corticosteroid has emerged. Amifostine and oral enzymes were somewhat effective in preventing radiation-induced skin reactions in phase ii and phase iii trials respectively; further large randomized controlled trials should be undertaken to better investigate those products. Biafine cream (Ortho–McNeil Pharmaceuticals, Titusville, NJ, U.S.A.) was found not to be superior to standard regimes in the prevention of radiation-induced skin reactions (n = 6). In conclusion, the evidence is insufficient to support the use of a particular agent for the prevention and management of acute radiation-induced skin reactions. Future trials should focus on comparing agents and approaches that, in phase i and ii trials, suggest efficacy. These future phase iii randomized controlled trials must clearly distinguish between preventive and management strategies for radiation-induced dermatitis. Only then can evidence-based guidelines be developed, with the hope of standardizing the approach across centres and of improving the prevention and management of radiation-induced dermatitis. PMID:20697521

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

2010-01-01

274

Physical activity during daily life and brachial artery flow-mediated dilation in peripheral arterial disease  

PubMed Central

We determined whether higher levels of physical activity in daily life are associated with better brachial artery flow-mediated dilation (FMD) among individuals with lower extremity peripheral arterial disease (PAD). Participants were 111 men and women with PAD (ankle–brachial index (ABI) ? 0.95) who completed baseline testing in the Study to Improve Leg Circulation (SILC). We evaluated FMD of the brachial artery at baseline and at 60 seconds following 4 minutes of suprasystolic blood pressure cuff inflation. Physical activity was measured continuously over 7 days using a vertical accelerometer (Caltrac) and a pedometer (Digiwalker). Adjusting for age, sex, race, ABI, cardiovascular risk factors and other potential confounders, higher levels of physical activity were associated with a greater percent change in brachial artery FMD at 60 seconds post cuff deflation for both Caltrac (1st tertile of activity +4.81% change; 2nd tertile +4.60% change; 3rd tertile +7.23% change; p-trend = 0.018) and the Digiwalker (1st tertile of activity +3.76% change; 2nd tertile +6.25% change; 3rd tertile +7.25% change; p-trend = 0.001). Similar findings were observed for absolute change in brachial artery FMD 60 seconds after cuff deflation. In conclusion, higher levels of physical activity during daily life are associated significantly and independently with better brachial artery FMD among individuals with PAD, even after adjusting for confounders. PMID:19651668

Payvandi, Laila; Dyer, Alan; McPherson, David; Ades, Philip; Stein, James; Liu, Kiang; Ferrucci, Luigi; Criqui, Michael H; Guralnik, Jack M; Lloyd-Jones, Donald; Kibbe, Melina R; Liang, Susan T; Kane, Bonnie; Pearce, William H; Verta, Michael; McCarthy, Walter J; Schneider, Joseph R; Shroff, Adhir; McDermott, Mary M

2009-01-01

275

Vascular patterns of upper limb: an anatomical study with accent on superficial brachial artery  

PubMed Central

The aim of the study was to evaluate the terminal segmentation of the axillary artery and to present four cases of anomalous branching of the axillary artery, the superficial brachial artery (arteria brachialis superficialis), which is defined as the brachial artery that runs superficially to the median nerve. Totally, 130 cadaveric upper arms embalmed by classical formaldehyde technique from collections of the Department of Anatomy, Third Faculty of Medicine, Charles University in Prague, were macroscopically dissected with special focus on the branching arrangement of the axillary artery. The most distal part of the axillary artery (infrapectoral part) terminated in four cases as a bifurcation into two terminal branches: the superficial brachial artery and profunda brachii artery, denominated according to their relation to the median nerve. The profunda brachii artery primarily gave rise to the main branches of the infrapectoral part of the axillary artery. The superficial brachial artery descended to the cubital fossa where it assumed the usual course of the brachial artery in two cases and in the other two cases its branches (the radial and ulnar arteries) passed superficially to the flexors. The incidence of the superficial brachial artery in our study was 5% of cases. The reported incidence is a bit contradictory, from 0.12% to 25% of cases. The anatomical knowledge of the axillary region is of crucial importance for neurosurgeons and specialists using the radiodiagnostic techniques, particularly in cases involving traumatic injuries. The improved knowledge would allow more accurate diagnostic interpretations and surgical treatment. PMID:21342134

Kachlik, David; Konarik, Marek; Baca, Vaclav

2011-01-01

276

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

277

On the mechanism of radiation-induced emesis: The role of serotonin  

SciTech Connect

The aim of this study was to determine the mechanism of action of radiation-induced emesis by determining the incidence of radiation-induced emesis following hemibody irradiation; the effects of specific antiemetics especially ondansetron, a 5-hydroxytryptamine receptor antagonist, and to determine the relationship between radiation-induced emesis and serotonin (5-hydroxytryptamine) through its active metabolite, 5-hydroxyindoleacetic acid (5-HIAA). Forty-one patients received 53 hemibody treatments of 5-8 Gy following intravenous hydration. The patients were divided into three groups according to prehemibody irradiation treatment: Group A: no pretreatment antiemetics, 30 patients; Group B: nonondansetron antiemetics (metoclopramide, dexamethasone, prochlorperazine), ten patients; and Group C: ondansetron, 13 patient. The incidence of radiation-induced emesis was determined prehemibody irradiation or baseline and at 1 h posthemibody irradiation in 38 patients and the results expressed as the percent change in 5-HIAA (ng/ug creatinine). The incidence of radiation-induced emesis was 82% (14/17) following upper/mid hemibody irradiation and 15% (2/11) following lower hemibody irradiation in Group A; 50% (3/6) and 25% (1/4) following upper/mid and lower hemibody irradiation respectively, in Group B/; and 0% (p/13) after upper/mid hemibody irradiation in Group C. The incidence of emesis was significantly different (p<0.001) between the patients of Group A and C who received upper/mid hemibody irradiation. The percent change in 5-HIAA excretion following upper/mid hemibody irradiation were greatest in Group A and smallest in Group C (p<0.002). The degree of change following lower hemibody irradiation (15% incidence of emesis) in Group A was lower than upper/mid hemibody irradiation of the same group. 17 refs., 3 figs., 2 tabs.

Scarantino, C.W.; Ornitz, R.D.; Hoffman, L.G. [Rex Cancer Center, Raleigh, NC (United States)] [and others

1994-11-15

278

Influence of interface sink strength on the reduction of radiation-induced defect concentrations and fluxes in materials with large interface area per unit volume  

E-print Network

We use a reaction–diffusion model to demonstrate that buried interfaces in polycrystalline composites simultaneously reduce both the concentrations and the fluxes of radiation-induced defects. The steady-state radiation-induced ...

Hoagland, R. G.

279

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

SciTech Connect

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

Palayoor, S.T.; Macklis, R.M.; Bump, E.A.; Coleman, C.N. [Harvard Medical School, Boston, MA (United States)

1995-03-01

280

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

PubMed Central

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

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

2012-01-01

281

Ceramide Biogenesis Is Required for Radiation-Induced Apoptosis in the Germ Line of C. elegans  

PubMed Central

Ceramide engagement in apoptotic pathways has been a topic of controversy. To address this controversy, we tested loss-of-function (lf) mutants of conserved genes of sphingolipid metabolism in Caenorhabditis elegans. Although somatic (developmental) apoptosis was unaffected, ionizing radiation–induced apoptosis of germ cells was obliterated upon inactivation of ceramide synthase and restored upon microinjection of long-chain natural ceramide. Radiation-induced increase in the concentration of ceramide localized to mitochondria and was required for BH3-domain protein EGL-1–mediated displacement of CED-4 (an APAF-1–like protein) from the CED-9 (a Bcl-2 family member)/CED-4 complex, an obligate step in activation of the CED-3 caspase. These studies define CEP-1 (the worm homolog of the tumor suppressor p53)–mediated accumulation of EGL-1 and ceramide synthase–mediated generation of ceramide through parallel pathways that integrate at mitochondrial membranes to regulate stress-induced apoptosis. PMID:18832646

Deng, Xinzhu; Yin, Xianglei; Allan, Richard; Lu, Diane D.; Maurer, Carine W.; Haimovitz-Friedman, Adriana; Fuks, Zvi; Shaham, Shai; Kolesnick, Richard

2008-01-01

282

Hyperbaric oxygen in the treatment of radiation-induced optic neuropathy  

SciTech Connect

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

Guy, J.; Schatz, N.J.

1986-08-01

283

Gamma radiation induced effects in floppy and rigid Ge-containing chalcogenide thin films  

NASA Astrophysics Data System (ADS)

We explore the radiation induced effects in thin films from the Ge-Se to Ge-Te systems accompanied with silver radiation induced diffusion within these films, emphasizing two distinctive compositional representatives from both systems containing a high concentration of chalcogen or high concentration of Ge. The studies are conducted on blanket chalcogenide films or on device structures containing also a silver source. Data about the electrical conductivity as a function of the radiation dose were collected and discussed based on material characterization analysis. Raman Spectroscopy, X-ray Diffraction Spectroscopy, and Energy Dispersive X-ray Spectroscopy provided us with data about the structure, structural changes occurring as a result of radiation, molecular formations after Ag diffusion into the chalcogenide films, Ag lateral diffusion as a function of radiation and the level of oxidation of the studied films. Analysis of the electrical testing suggests application possibilities of the studied devices for radiation sensing for various conditions.

Ailavajhala, Mahesh S.; Gonzalez-Velo, Yago; Poweleit, Christian; Barnaby, Hugh; Kozicki, Michael N.; Holbert, Keith; Butt, Darryl P.; Mitkova, Maria

2014-01-01

284

A case of radiation-induced osteosarcoma treated effectively by boron neutron capture therapy.  

PubMed

We treated a 54-year-old Japanese female with a recurrent radiation-induced osteosarcoma arising from left occipital skull, by reactor-based boron neutron capture therapy (BNCT). Her tumor grew rapidly with subcutaneous and epidural extension. She eventually could not walk because of cerebellar ataxia. The tumor was inoperable and radioresistant. BNCT showed a marked initial therapeutic effect: the subcutaneous/epidural tumor reduced without radiation damage of the scalp except hair loss and the patient could walk again only 3 weeks after BNCT. BNCT seems to be a safe and very effective modality in the management of radiation-induced osteosarcomas that are not eligible for operation and other treatment modalities. PMID:25366059

Futamura, Gen; Kawabata, Shinji; Siba, Hiroyuki; Kuroiwa, Toshihiko; Suzuki, Minoru; Kondo, Natsuko; Ono, Koji; Sakurai, Yoshinori; Tanaka, Minoru; Todo, Tomoki; Miyatake, Shin-Ichi

2014-11-01

285

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

286

Gamma radiation induced effects in floppy and rigid Ge-containing chalcogenide thin films  

SciTech Connect

We explore the radiation induced effects in thin films from the Ge-Se to Ge-Te systems accompanied with silver radiation induced diffusion within these films, emphasizing two distinctive compositional representatives from both systems containing a high concentration of chalcogen or high concentration of Ge. The studies are conducted on blanket chalcogenide films or on device structures containing also a silver source. Data about the electrical conductivity as a function of the radiation dose were collected and discussed based on material characterization analysis. Raman Spectroscopy, X-ray Diffraction Spectroscopy, and Energy Dispersive X-ray Spectroscopy provided us with data about the structure, structural changes occurring as a result of radiation, molecular formations after Ag diffusion into the chalcogenide films, Ag lateral diffusion as a function of radiation and the level of oxidation of the studied films. Analysis of the electrical testing suggests application possibilities of the studied devices for radiation sensing for various conditions.

Ailavajhala, Mahesh S.; Mitkova, Maria [Department of Electrical Engineering, Boise State University, 1910 University Dr. Boise, Idaho 83725-2075 (United States); Gonzalez-Velo, Yago; Barnaby, Hugh; Kozicki, Michael N.; Holbert, Keith [School of Electrical, Computer and Energy Engineering, Arizona State University, Tempe, Arizona 85287-9309 (United States); Poweleit, Christian [Department of Physics, Arizona State University, Tempe, Arizona 85287-1504 (United States); Butt, Darryl P. [Department of Material Science and Engineering, Boise State University, 1910 University Dr. Boise, Idaho 83725-2090 (United States)

2014-01-28

287

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

SciTech Connect

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

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

1987-01-01

288

Review of research on use of radiation-induced mutations in crop breeding in Japan  

Microsoft Academic Search

In Japan, the research on radiation-induced mutation has been conducted as one of the promising methods of plant breeding. Although in the beginning the principal methods used are X-rays and 32P, we now have various kinds of radiation facilities available for mutation breeding. The fundamental aspects of mutation breeding are investigated at several universities and institutes, and the practical breeding

Takane Matsuo; Hikoyuki Yamaguchi

1962-01-01

289

Amelioration of radiation-induced hematopoietic and gastrointestinal damage by Ex-RAD® in mice  

PubMed Central

The aim of the present study was to assess recovery from hematopoietic and gastrointestinal damage by Ex-RAD®, also known as ON01210.Na (4-carboxystyryl-4-chlorobenzylsulfone, sodium salt), after total body radiation. In our previous study, we reported that Ex-RAD, a small-molecule radioprotectant, enhances survival of mice exposed to gamma radiation, and prevents radiation-induced apoptosis as measured by the inhibition of radiation-induced protein 53 (p53) expression in cultured cells. We have expanded this study to determine best effective dose, dose-reduction factor (DRF), hematological and gastrointestinal protection, and in vivo inhibition of p53 signaling. A total of 500 mg/kg of Ex-RAD administered at 24 h and 15 min before radiation resulted in a DRF of 1.16. Ex-RAD ameliorated radiation-induced hematopoietic damage as monitored by the accelerated recovery of peripheral blood cells, and protection of granulocyte macrophage colony-forming units (GM-CFU) in bone marrow. Western blot analysis on spleen indicated that Ex-RAD treatment inhibited p53 phosphorylation. Ex-RAD treatment reduces terminal deoxynucleotidyl transferase mediated dUTP nick end labeling assay (TUNEL)-positive cells in jejunum compared with vehicle-treated mice after radiation injury. Finally, Ex-RAD preserved intestinal crypt cells compared with the vehicle control at 13 and 14 Gy. The results demonstrated that Ex-RAD ameliorates radiation-induced peripheral blood cell depletion, promotes bone marrow recovery, reduces p53 signaling in spleen and protects intestine from radiation injury. PMID:22843617

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

2012-01-01

290

Protection from radiation-induced apoptosis by the radioprotector amifostine (WR-2721) is radiation dose dependent.  

PubMed

The radioprotective agent amifostine is a free radical scavenger that can protect cells from the damaging effects of ionising radiation when administered prior to radiation exposure. However, amifostine has also been shown to protect cells from chromosomal mutations when administered after radiation exposure. As apoptosis is a common mechanism by which cells with mutations are removed from the cell population, we investigated whether amifostine stimulates apoptosis when administered after radiation exposure. We chose to study a relatively low dose which is the maximum radiation dose for radiation emergency workers (0.25 Gy) and a high dose relevant to radiotherapy exposures (6 Gy). Mice were administered 400 mg/kg amifostine 30 min before, or 3 h after, whole-body irradiation with 0.25 or 6 Gy X-rays and apoptosis was analysed 3 or 7 h later in spleen and bone marrow. We observed a significant increase in radiation-induced apoptosis in the spleen of mice when amifostine was administered before or after 0.25 Gy X-rays. In contrast, when a high dose of radiation was used (6 Gy), amifostine caused a reduction in radiation-induced apoptosis 3 h post-irradiation in spleen and bone marrow similar to previously published studies. This is the first study to investigate the effect of amifostine on radiation-induced apoptosis at a relatively low radiation dose and the first to demonstrate that while amifostine can reduce apoptosis from high doses of radiation, it does not mediate the same effect in response to low-dose exposures. These results suggest that there may be a dose threshold at which amifostine protects from radiation-induced apoptosis and highlight the importance of examining a range of radiation doses and timepoints. PMID:24459009

Ormsby, Rebecca J; Lawrence, Mark D; Blyth, Benjamin J; Bexis, Katrina; Bezak, Eva; Murley, Jeffrey S; Grdina, David J; Sykes, Pamela J

2014-02-01

291

Effect of G\\/M ratio on the radiation-induced degradation of sodium alginate  

Microsoft Academic Search

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

Murat Sen; Stojan Rendevski; Pinar Akkas Kavakli; Amir Sepehrianazar

2010-01-01

292

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

SciTech Connect

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

Jensen, Ashley W. [Department of Radiation Oncology, Mayo Clinic, Rochester, MN (United States); Brown, Paul D. [Department of Radiation Oncology, Mayo Clinic, Rochester, MN (United States); Pollock, Bruce E. [Department of Radiation Oncology, Mayo Clinic, Rochester, MN (United States); Department of Neurologic Surgery, Mayo Clinic, Rochester, MN (United States); Stafford, Scott L. [Department of Radiation Oncology, Mayo Clinic, Rochester, MN (United States); Link, Michael J. [Department of Neurologic Surgery, Mayo Clinic, Rochester, MN (United States); Garces, Yolanda I. [Department of Radiation Oncology, Mayo Clinic, Rochester, MN (United States); Foote, Robert L. [Department of Radiation Oncology, Mayo Clinic, Rochester, MN (United States); Gorman, Deborah A. [Department of Neurologic Surgery, Mayo Clinic, Rochester, MN (United States); Schomberg, Paula J. [Department of Radiation Oncology, Mayo Clinic, Rochester, MN (United States)

2005-05-01

293

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

294

Gamma Knife radiosurgery for meningiomas: four cases of radiation-induced edema.  

PubMed

We review 48 cases of meningioma treated with Gamma Knife radiosurgery. The mean marginal dose was 15 Gy and the mean follow-up was 12 months. Follow-up computed tomography and magnetic resonance imaging showed tumor shrinkage in 19 cases, central necrosis in 1 case, loss of contrast enhancement in 1 case, and no change in 27 cases. We noted 4 cases of radiation-induced edema in supratentorial meningiomas. PMID:9032855

Nakamura, S; Hiyama, H; Arai, K; Nakaya, K; Sato, H; Hayashi, M; Kawamata, T; Izawa, M; Takakura, K

1996-01-01

295

Chemical selectivity and energy transfer mechanisms in the radiation-induced modification of polyethersulphone  

Microsoft Academic Search

The mechanism of radiation-induced degradation of PES has been studied in a great detail by using XPS technique. PES films have been irradiated both with 6 keV Ar and 3 keV e? beams. The Ar irradiation is assumed to be representative of the processes which strictly depend on collisional energy loss, while the electron irradiation puts in evidence mainly the

G. Marletta; F. Iacona

1996-01-01

296

Homeopathic treatment of radiation-induced itching in breast cancer patients. A prospective observational study  

Microsoft Academic Search

Following surgery for carcinoma of the breast, patients receive local radiotherapy. This can cause itching, which may be severe, in the radiation field. The affected skin usually is dry, rough and red. Twenty-five patients were treated homeopathically for radiation-induced itching. Fourteen patients developed itching during their course of postoperative radiation at 27 days median (range: 14–40). Eleven patients experienced itching

O Schlappack

2004-01-01

297

Effect of gamma irradiation conditions on the radiation-induced degradation of isobutylene–isoprene rubber  

Microsoft Academic Search

The effect of gamma irradiation conditions on the radiation-induced degradation of uncrosslinked, commercial isobutylene–isoprene rubbers has been investigated in this study. Influence of dose rate and irradiation atmosphere on the degradation of butyl rubber has been followed by viscosimetric and chromatographic analyses. Limiting viscosity number of all butyl rubbers decreased sharply up to 100 kGy and leveled off at around

M. ?en; C. Uzun; Ö. Kantoglu; S. M. Erdo?an; V. Deniz; O. Güven

2003-01-01

298

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

299

A new mechanism for photo- and radiation-induced decomposition of sphingolipids.  

PubMed

Data have been obtained showing regularities in product formation following radiolysis of serinol, lysosphingomyelin and photolysis of N-(2-hydroxypropyl)hexanamide, sphingomyelin, which point to the possibility of photo- and radiation-induced destruction of the named substrates via a C-C bond rupture. The key stage of this process is the formation and decomposition of N-centered radicals generated from the starting compounds. PMID:21140235

Lisovskaya, Alexandra G; Shadyro, Oleg I; Edimecheva, Irina P

2011-03-01

300

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

301

Radiation induced CO2 reduction in an aqueous medium suspended with iron powder  

Microsoft Academic Search

Radiation induced CO2 conversion to CO and hydrocarbon has been studied using a solution suspended with iron powder and saturated with CO2. Due to the corrosion enhanced by gamma-rays, H2 has become the most dominant product of all. Corresponding to the rapid H2 formation, a little hydrocarbon containing less than 4 carbon atoms has been produced in the initial period

Norihiko Fujita; Harutsugu Morita; Chihiro Matsuura; Daisuke Hiroishi

1994-01-01

302

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

PubMed

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. PMID:24137346

Liu, Hao; Xue, Jian-Xing; Li, Xing; Ao, Rui; Lu, You

2013-08-01

303

Stem cells and the repair of radiation-induced salivary gland damage.  

PubMed

Hyposalivation underlying xerostomia after radiotherapy is still a major problem in the treatment of head and neck cancer. Stem cell therapy may provide a means to reduce radiation-induced hyposalivation and improve the quality of life of patients. This review discusses the current status in salivary gland stem cell research with respect to their potential to attenuate salivary gland dysfunction. Knowledge on the embryonic development, homeostasis and regeneration after atrophy of the salivary glands has provided important knowledge on the location of the salivary gland as well as on the factors that influence proliferation and differentiation. This knowledge has helped to locate, isolate and characterize cell populations that contain the salivary gland stem cell, although the exact tissue stem cell is still unidentified. The role that stem/progenitor cells play in the response to radiation and the factors that can influence stem/progenitor induced proliferation and differentiation are discussed. Finally, the mobilization and transplantation of stem cells and supportive cells and their potential to attenuate radiation-induced salivary gland damage are discussed. Based on the major advances made in the field of stem cell research, stem cell-based therapy has great potential to allow prevention or treatment of radiation-induced hyposalivation. PMID:20796229

Coppes, R P; Stokman, M A

2011-03-01

304

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

PubMed

The present study evaluated the hepatoprotective effect of aqueous ethanolic Moringa oleifera leaf extract (MoLE) against radiation-induced oxidative stress, which is assessed in terms of inflammation and lipid peroxidation. Swiss albino mice were administered MoLE (300 mg/kg of body weight) for 15 consecutive days before exposing them to a single dose of 5 Gy of ??Co ?-irradiation. Mice were sacrificed at 4 hours after irradiation. Liver was collected for immunoblotting and biochemical tests for the detection of markers of hepatic oxidative stress. Nuclear translocation of nuclear factor kappa B (NF-?B) and lipid peroxidation were augmented, whereas the superoxide dismutase (SOD), catalase (CAT), reduced glutathione (GSH), and ferric reducing antioxidant power (FRAP) values were decreased by radiation exposure. Translocation of NF-?B from cytoplasm to nucleus and lipid peroxidation were found to be inhibited, whereas increases in SOD, CAT, GSH, and FRAP were observed in the mice treated with MoLE prior to irradiation. Therefore pretreatment with MoLE protected against ?-radiation-induced liver damage. The protection may be attributed to the free radical scavenging activity of MoLE, through which it can ameliorate radiation-induced oxidative stress. PMID:21861723

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

2011-10-01

305

Radiation-induced apoptosis in a murine T-cell hybridoma.  

PubMed

Induction of an apoptotic cell death was studied in a mouse T-cell hybridoma. Apoptosis was induced in these cells following exposure to dexamethasone, X-radiation, 43 degrees C heat shock, A254 light, and hydrogen peroxide. In 5-Gy-exposed cells, a radiation-induced G2 phase cell cycle progression block was maximum by 8 h. The cells began to escape this progression block by 10 h. Nuclear DNA fragmentation and uptake of the vital dye trypan blue began at 12 and 14 h, respectively, and were complete by 28 h. X-radiation-induced cell death was diminished when cells were irradiated in the presence of dimethyl sulfoxide, indicating that cell death was induced by oxidative cell damage. Substitution of nuclear DNA with bromodeoxyuridine enhanced death in cells exposed to either X-radiation or A310 light, indicating that apoptosis could be induced by DNA damage. The results are consistent with radiation-induced apoptosis being stimulated by oxidative DNA damage. DNA damage stimulates a long-lived signal which controls the expression of apoptosis. Apoptosis is expressed in the G1 phase of the cell cycle subsequent to the cell irradiation. PMID:1737350

Warters, R L

1992-02-15

306

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

PubMed Central

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

Jenrow, Kenneth A.; Brown, Stephen L.

2014-01-01

307

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. 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

308

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

309

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

PubMed

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

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

2014-10-01

310

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. PMID:23905085

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

2013-01-01

311

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

SciTech Connect

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

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

1986-01-01

312

Obstetric brachial plexus palsy associated with breech delivery.  

PubMed

A review of the English literature revealed that only two birth palsy centers have specifically reviewed their experience with obstetrical palsy associated with breech delivery. The aim of this paper is to review the author's center's experience with birth palsy associated with breech delivery, compare their epidemiological and surgical findings with previous studies, and describe their management approach to this unique injury. A total of 34 limbs were studied. Erb's palsy was seen in 32 limbs and total palsy was seen in the remaining 2 limbs. The mean birth weight was low (2.3 kg). Six patients had bilateral lesions and 3 patients had phrenic nerve palsy. In their center, the indication for primary brachial plexus exploration is the lack of active elbow flexion against gravity at 4 months of age. A study of the natural history showed that 58% of limbs had full spontaneous recovery, 21% had good but partial recovery, and the prognosis was considered to be poor in the remaining 21% of limbs because active elbow flexion was not evident by 4 months of age. Intraoperatively, the usual lesion was C5/C6 avulsion or avulsion in situ, which seemed to be specific for breech deliveries. Their approach for management is described, including the role of Oberlin's ulnar nerve to biceps nerve transfer in these cases. Finally, the lack of contractures at the shoulder and elbow in these patients are explained. PMID:12966236

Al-Qattan, M M

2003-09-01

313

Inflammation and neuropathic attacks in hereditary brachial plexus neuropathy  

PubMed Central

Objective: To study the role of mechanical, infectious, and inflammatory factors inducing neuropathic attacks in hereditary brachial plexus neuropathy (HBPN), an autosomal dominant disorder characterised by attacks of pain and weakness, atrophy, and sensory alterations of the shoulder girdle and upper limb muscles. Methods: Four patients from separate kindreds with HBPN were evaluated. Upper extremity nerve biopsies were obtained during attacks from a person of each kindred. In situ hybridisation for common viruses in nerve tissue and genetic testing for a hereditary tendency to pressure palsies (HNPP; tomaculous neuropathy) were undertaken. Two patients treated with intravenous methyl prednisolone had serial clinical and electrophysiological examinations. One patient was followed prospectively through pregnancy and during the development of a stereotypic attack after elective caesarean delivery. Results: Upper extremity nerve biopsies in two patients showed prominent perivascular inflammatory infiltrates with vessel wall disruption. Nerve in situ hybridisation for viruses was negative. There were no tomaculous nerve changes. In two patients intravenous methyl prednisolone ameliorated symptoms (largely pain), but with tapering of steroid dose, signs and symptoms worsened. Elective caesarean delivery did not prevent a typical postpartum attack. Conclusions: Inflammation, probably immune, appears pathogenic for some if not all attacks of HBPN. Immune modulation may be useful in preventing or reducing the neuropathic attacks, although controlled trials are needed to establish efficacy, as correction of the mutant gene is still not possible. The genes involved in immune regulation may be candidates for causing HBPN disorders. PMID:12082044

Klein, C; Dyck, P; Friedenberg, S; Burns, T; Windebank, A; Dyck, P

2002-01-01

314

Phrenic nerve transfer to the musculocutaneous nerve for the repair of brachial plexus injury: electrophysiological characteristics  

PubMed Central

Phrenic nerve transfer is a major dynamic treatment used to repair brachial plexus root avulsion. We analyzed 72 relevant articles on phrenic nerve transfer to repair injured brachial plexus that were indexed by Science Citation Index. The keywords searched were brachial plexus injury, phrenic nerve, repair, surgery, protection, nerve transfer, and nerve graft. In addition, we performed neurophysiological analysis of the preoperative condition and prognosis of 10 patients undergoing ipsilateral phrenic nerve transfer to the musculocutaneous nerve in our hospital from 2008 to 201 3 and observed the electromyograms of the biceps brachii and motor conduction function of the musculocutaneous nerve. Clinically, approximately 28% of patients had brachial plexus injury combined with phrenic nerve injury, and injured phrenic nerve cannot be used as a nerve graft. After phrenic nerve transfer to the musculocutaneous nerve, the regenerated potentials first appeared at 3 months. Recovery of motor unit action potential occurred 6 months later and became more apparent at 12 months. The percent of patients recovering ‘excellent’ and ‘good’ muscle strength in the biceps brachii was 80% after 18 months. At 12 months after surgery, motor nerve conduction potential appeared in the musculocutaneous nerve in seven cases. These data suggest that preoperative evaluation of phrenic nerve function may help identify the most appropriate nerve graft in patients with an injured brachial plexus. The functional recovery of a transplanted nerve can be dynamically observed after the surgery.

Liu, Ying; Xu, Xun-cheng; Zou, Yi; Li, Su-rong; Zhang, Bin; Wang, Yue

2015-01-01

315

The rabbit brachial plexus as a model for nerve repair surgery--histomorphometric analysis.  

PubMed

One of the most devastating injuries to the upper limb is trauma caused by the avulsion. The anatomical structure of the rabbit's brachial plexus is similar to the human brachial plexus. The aim of our study was to analyze the microanatomy and provide a detailed investigation of the rabbit's brachial plexus. The purpose of our research project was to evaluate the possibility of utilizing rabbit's plexus as a research model in studying brachial plexus injury. Studies included histomorphometric analysis of sampled ventral branches of spinal nerves C5, C6, C7, C8, and Th1, the cranial trunk, the medial part of the caudal trunk, the lateral part of the caudal trunk and peripheral nerve. Horizontal and vertical analysis was done considering following features: the axon diameter, fiber diameter and myelin sheath. The number of axons, nerve area, myelin fiber density and minimal diameter of myelin fiber, minimal axon diameter and myelin area was marked for each element. The changes between ventral branches of spinal nerves C5-Th1, trunks and peripheral nerve in which the myelin sheath, axon diameter and fiber diameter was assessed were statistically significant. It was found that the g-ratio has close value in the brachial plexus as in the peripheral nerve. The peak of these parameters was found in nerve trunks, and then decreased coherently with the nerves travelling peripherally. PMID:25284580

Reichert, Pawe?; Kie?bowicz, Zdzis?aw; Dzi?giel, Piotr; Pu?a, Bartosz; Kuryszko, Jan; Gosk, Jerzy; Boche?ska, Aneta

2015-02-01

316

PROBLEMATIKA BOLESTI U NEURALGICKÉ AMYOTROFIE BRACHIÁLNÍHO PLEXU THE ISSUE OF PAIN IN NEURALGIC AMYOTROPHIA OF BRACHIAL PLEXUS  

Microsoft Academic Search

SUMMARY Neuralgic amyotrophia of the brachial plexus most often starts with acute pain in the shoulder area, the cervical vertebrae or arm and only later does muscular impairment develop. Both the pain and the muscular impairment arise from the affliction of various areas of the brachial plexus. We focused on a group of five patients in whom we confirmed the

ONDØEJ HORÁÈEK; RADIM MAZANEC; JIØÍ KOZÁK; PAVEL KOLÁØ

317

A Modified Coracoid Approach to Infraclavicular Brachial Plexus Blocks Using a Double-Stimulation Technique in 300 Patients  

Microsoft Academic Search

Infraclavicular brachial plexus block is used less than other techniques of regional anesthesia for upper- limb surgery. We describe a modified coracoid ap- proach to the infraclavicular brachial plexus using a double-stimulation technique and assess its efficacy. Patients undergoing orthopedic surgery of the upper limb were included in this prospective study. The landmarks used were the coracoid process and the

Vincent Minville; Luc NGuyen; Clement Chassery; Paul Zetlaoui; Jean-Claude Pourrut; Claude Gris; Bernard Eychennes; Dan Benhamou; Kamran Samii

2005-01-01

318

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

319

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

NASA Astrophysics Data System (ADS)

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

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

320

Article title: Potential Mechanisms Involved in Resistant Phenotype of MCF-7 Breast Carcinoma Cells to Ionizing Radiation-Induced Apoptosis  

E-print Network

to Ionizing Radiation-Induced Apoptosis Authors: Yan-ling Wang 1,2,3 , Hong Zhang 1,2 * , Ning Li 1,2,3 , Xiao Department of Radiotherapy, Gansu Tumor Hospital, Lanzhou 730050, China * Corresponding author: Hong Zhang

Paris-Sud XI, Université de

321

Protection of cellular DNA and membrane from ?-radiation-induced damages and enhancement in DNA repair by sesamol.  

PubMed

Sesamol (SM), a nutritional phenolic antioxidant compound present in sesame seeds, protected pBR 322 DNA from gamma radiation-induced damages. SM prevented gamma radiation-induced degradation of covalently closed circular form of plasmid DNA in a concentration-dependent manner. Also SM protected cellular DNA of mouse blood leukocytes exposed to 4?Gy gamma radiation, ex vivo, as revealed by the data from alkaline comet assay studies. SM (5 mM) showed a faster time-dependant decrease of the radiation-induced DNA damage in mouse blood leukocytes following postirradiation incubation ex vivo, which could be attributed to enhanced DNA repair. SM protected the biomembranes from radiation-induced lipid peroxidation. Thus, SM could act as a radioprotector for the biomembranes and cellular DNA against the deleterious effects of ionizing radiation. PMID:21204756

Nair, Gopakumar Gopinathan; Nair, Cherupally Krishnan Krishnan

2010-12-01

322

Radiation-induced crypt intestinal epithelial cell apoptosis in vivo involves both caspase-3-dependent and -independent pathways.  

PubMed

Caspases play a major role in virtually all forms of apoptosis. Radiation is well known to induce apoptosis of crypt intestinal epithelial cells (IEC). Here, we examined the role of caspase-3 in radiation-induced IEC apoptosis. We demonstrate that while caspase-3 is present in IEC and activated upon irradiation, IEC in caspase-3-deficient mice partially underwent radiation-induced apoptosis. Typical morphological changes of IEC undergoing radiation-induced apoptosis (ie, blebbing, shrinkage, and nuclear condensation) can occur independently of caspase-3; however DNA fragmentation, as analyzed by terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling (TUNEL) staining, is mostly, but not entirely, caspase-3-dependent. Overall, these results demonstrate that radiation-induced crypt IEC apoptosis has both caspase-3-independent and -dependent components. PMID:12498307

Inagaki-Ohara, Kyoko; Takamura, Noriaki; Yada, Shinichiro; Alnadjim, Ziad; Liu, Erding; Yu, Xiaohong; Yoshida, Hiroki; Lin, Tesu

2002-12-01

323

Comparison of calf and brachial blood pressures in infants: is there a difference between calf and brachial blood pressures?  

PubMed

The standard of care is to obtain a noninvasive blood pressure (NIBP) measurement from the right upper arm. However, in the pediatric population it is common practice to take blood pressure (BP) measurements from the calf/upper ankle. Nurses commonly take calf NIBPs for many reasons, but there is little evidence to support calf BPs as a reliable site for BP measurement. Furthermore, there is conflicting evidence. Some studies suggest no difference between the calf and the upper arm BPs, whereas others conclude great variability between the two. The purpose of this study was to demonstrate the reliability of calf BPs, by showing no difference between brachial and calf BP measurements in neonates and infants ? 1 year old. From July 2008 to December 2008, a convenience sample of 52 subjects admitted to the Neonatal and Infant Critical Care Unit were enrolled into the study. Limb selection was not randomized. Three BPs were taken from the arm and 3 BPs were taken from the calf. Data were analyzed using a mixed analysis of variance (P = 0.05). The difference was not significant for systolic (P = 0.6159) or mean BP (P = 0.1298), but it was significant for diastolic (P = 0.0263). The authors concluded that these results support the current practice of bedside nurses and contribute to the limited knowledge on this topic. Because there was a difference in the diastolic BPs, further investigation is needed. PMID:25455319

Tran, Nhu; Hackett, Heather; Cadaver, Carol; Fichera, Sharon; Azen, Colleen

2014-12-01

324

Electron Spin Resonance Study of Radiation-Induced Paramagnetic Defects in Silicon-Dioxide Grown on (100) Silicon Substrates  

Microsoft Academic Search

Electron spin resonance spectroscopy was used to investigate radiation-induced point defects in Si\\/SiO _2 structures with (100) silicon substrates. It was found that the radiation-induced point defects are quite similar to defects generated in Si\\/SiO _2 structures grown on (111) silicon substrates. In both cases an oxygen deficient silicon center, the E^' defect, appears to be responsible for trapped positive

Yong Yun Kim

1988-01-01

325

A new model for radiation-induced grain boundary segregation with grain boundary movement in concentrated alloy system  

Microsoft Academic Search

We have developed a new model for radiation-induced grain boundary migration (RIGM) and radiation-induced segregation (RIS) for austenitic iron-chromium-nickel alloy system. It was assumed that the RIS was induced by diffusional and annihilation processes of excess point defects at the grain boundary, and the RIGM occurred due to rearrangement process of atoms on one of the interfacial planes by annihilation

N. Sakaguchi; S. Watanabe; H. Takahashi

2005-01-01

326

A new rat model of neuropathic pain: Complete brachial plexus avulsion.  

PubMed

Brachial plexus avulsion (BPA) is one of the major injuries in motor vehicle accidents and may result in neuropathic pain. Accumulating evidence suggests that 30-80% of BPA developed neuropathic pain in human. In our study, complete brachial plexus avulsion (C5-T1) rats model leads to the results that 37.5% of rats had long-lasting (up to 6 months) mechanical allodynia and cold allodynia. We observed the activation of astrocyte and microglial in cervical spinal cord after BPA. Complete brachial plexus avulsion mimics human nerve root traction injury following traffic accidents. The complete BPA rat model approach human injuries and can be used for further investigations. PMID:25596440

Wang, Le; Yuzhou, Liu; Yingjie, Zhou; Jie, Lao; Xin, Zhao

2015-03-01

327

Double free gracilis muscle transfer after complete brachial plexus injury: First Canadian experience.  

PubMed

Traumatic brachial plexus root avulsions are devastating injuries, and are complex and challenging to reconstruct. Double free muscle transfer using the gracilis muscles is a potentially effective method of restoring upper extremity function. The authors report on the first two patients treated using this technique in Canada. Both sustained traumatic brachial plexus root avulsion injuries resulting in a flail arm. In the first step of this two-stage procedure, a gracilis muscle was transferred to restore elbow flexion, and wrist and digit extension. Months later, the transfer of the second gracilis muscle was performed to enhance elbow flexion and to enable wrist and digit flexion. Postoperatively, both patients achieved Medical Research Council grade 4 elbow flexion, functional handgrip and were able to return to gainful employment. Patient satisfaction was high and active range of motion improved substantially. The authors' experience supports the use of this technique following severe brachial plexus injury. PMID:25152644

Elzinga, Kate; Zuo, Kevin J; Olson, Jaret L; Morhart, Michael; Babicki, Sasha; Chan, K Ming

2014-01-01

328

Double free gracilis muscle transfer after complete brachial plexus injury: First Canadian experience  

PubMed Central

Traumatic brachial plexus root avulsions are devastating injuries, and are complex and challenging to reconstruct. Double free muscle transfer using the gracilis muscles is a potentially effective method of restoring upper extremity function. The authors report on the first two patients treated using this technique in Canada. Both sustained traumatic brachial plexus root avulsion injuries resulting in a flail arm. In the first step of this two-stage procedure, a gracilis muscle was transferred to restore elbow flexion, and wrist and digit extension. Months later, the transfer of the second gracilis muscle was performed to enhance elbow flexion and to enable wrist and digit flexion. Postoperatively, both patients achieved Medical Research Council grade 4 elbow flexion, functional handgrip and were able to return to gainful employment. Patient satisfaction was high and active range of motion improved substantially. The authors’ experience supports the use of this technique following severe brachial plexus injury. PMID:25152644

Elzinga, Kate; Zuo, Kevin J; Olson, Jaret L; Morhart, Michael; Babicki, Sasha; Chan, K Ming

2014-01-01

329

Different Learning Curves for Axillary Brachial Plexus Block: Ultrasound Guidance versus Nerve Stimulation  

PubMed Central

Little is known about the learning of the skills needed to perform ultrasound- or nerve stimulator-guided peripheral nerve blocks. The aim of this study was to compare the learning curves of residents trained in ultrasound guidance versus residents trained in nerve stimulation for axillary brachial plexus block. Ten residents with no previous experience with using ultrasound received ultrasound training and another ten residents with no previous experience with using nerve stimulation received nerve stimulation training. The novices' learning curves were generated by retrospective data analysis out of our electronic anaesthesia database. Individual success rates were pooled, and the institutional learning curve was calculated using a bootstrapping technique in combination with a Monte Carlo simulation procedure. The skills required to perform successful ultrasound-guided axillary brachial plexus block can be learnt faster and lead to a higher final success rate compared to nerve stimulator-guided axillary brachial plexus block. PMID:21318138

Luyet, C.; Schüpfer, G.; Wipfli, M.; Greif, R.; Luginbühl, M.; Eichenberger, U.

2010-01-01

330

[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

331

Ultrasound-guided block of the brachial plexus at the humeral canal  

Microsoft Academic Search

Purpose  Conduction block of the brachial plexus block at the humeral canal, as described by Dupre, has certain clinical indications.\\u000a The aim of this preliminary study was to assess the feasibility of this technique under ultrasound guidance.\\u000a \\u000a \\u000a \\u000a Methods  After ultrasound evaluation of the brachial plexus at the humeral canal in 61 adult volunteers, we performed ultrasound-guided\\u000a blocks in another 20 adult patients.

Emmanuel Guntz; Vanessa Van den Broeck; Etienne Dereeper; Walid El Founas; Maurice Sosnowski

2009-01-01

332

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

PubMed

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. PMID:17822530

Motsitsi, Silas N S; Steyn, Rian R

2007-01-01

333

Brachial plexus injury as a complication after nerve block or vessel puncture.  

PubMed

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

Kim, Hyun Jung; Park, Sang Hyun; Shin, Hye Young; Choi, Yun Suk

2014-07-01

334

Sup-ER orthosis: an innovative treatment for infants with birth related brachial plexus injury.  

PubMed

Impairments in active and passive range of upper extremity supination and shoulder external rotation are common sequelae for children with delayed recovery from birth related brachial plexus injury. Orthotic intervention may complement traditional treatment strategies commonly employed in the newborn period. These authors describe their custom fabricated orthosis designed to balance shoulder growth and muscular function, and improve prognosis of long term functional outcomes for children with birth related brachial plexus injury. - Victoria Priganc, PhD, OTR, CHT, CLT, Practice Forum Editor. PMID:25042285

Durlacher, Kim M; Bellows, Doria; Verchere, Cynthia

2014-01-01

335

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. PMID:25031806

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

2014-01-01

336

[Chronic inflammatory demyelinating polyradiculoneuropathy with hypertrophy of spinal roots, brachial plexus and cranial nerves].  

PubMed

We report two patients who presented an atypical chronic inflammatory demyelinating polyradiculoneuropathy with massive nerve root and brachial plexus hypertrophy, and pseudotumoral supraclavicular mass. They also presented an hypertrophy of oculomotor and trigeminal nerves causing an exophthalmos and ocular palsy. Spinal root enlargement and cranial nerve hypertrophy was demonstrated by CT scanner and MRI. Brachial plexus biopsy showed a similar aspect of sural nerve, with an extensive onion bulb formation and perivascular inflammatory cell infiltration. There was an excellent response to steroids in both patients. PMID:12386527

Aïdi, S; El Alaoui Faris, M; Amarti, A; Belaïdi, H; Jiddane, M; Guezzaz, M; Medjel, A; Chkili, T

2002-09-01

337

[Trauma of the brachial plexus and associated vascular injury--a case report].  

PubMed

Acute vascular trauma in the axillary region is usually associated with brachial plexus injury and presents a great challenge to surgeon and formidable obstacle to restore a useful limb function. Interdisciplinary operative and postoperative approach is mandatory providing an optimal care of these severe patients. Here we present a case of neurovascular trauma that affected axillary artery and vein, complete transection associated with complete transection of the brachial plexus. Immediately after admission emergency surgery was performed and in postoperative follow up, after several operations and rehabilitation that continued for 24 months, entire functional recovery was achieved without any disabling consequences. PMID:20143599

Gveri?, Tugomir; Ivkosi?, Ante; Trajbar, Tomislav; Huljev, Dubravko; Nadini?, Vjenceslav; Barisi?, Jadranko; Skok, Ira; Gveri?-Ahmetasevi?, Snjezana; Bari?, Marko

2009-01-01

338

Brachial plexus injury in two red-tailed hawks (Buteo jamaicensis).  

PubMed

Two red-tailed hawks (Buteo jamaicensis), found near Deltaville, Virginia (USA), were evaluated because of inability to use a wing. Results of needle electromyographic studies of the affected wing muscles in both hawks were compatible with denervation. On euthanasia, one hawk had extensive axon and myelin loss with multifocal perivascular lymphocytic inflammation of its brachial plexus and radial nerve. Demyelination and axon loss in the dorsal white matter of the spinal cord on the affected side also were found at the origin of the brachial plexus. The other hawk's wing had not returned to functional status > 2 yr after injury. PMID:8383253

Shell, L; Richards, M; Saunders, G

1993-01-01

339

Down-regulation of ATM Protein Sensitizes Human Prostate Cancer Cells to Radiation-induced Apoptosis*  

PubMed Central

Treatment with the protein kinase C activator 12-O tetradecanoylphorbol 12-acetate (TPA) enables radiation-resistant LNCaP human prostate cancer cells to undergo radiation-induced apoptosis, mediated via activation of the enzyme ceramide synthase (CS) and de novo synthesis of the sphingolipid ceramide (Garzotto, M., Haimovitz-Friedman, A., Liao, W. C., White-Jones, M., Huryk, R., Heston, D. W. W., Cardon-Cardo, C., Kolesnick, R., and Fuks, Z. (1999) Cancer Res. 59, 5194-5201). Here, we show that TPA functions to decrease the cellular level of the ATM (ataxia telangiectasia mutated) protein, known to repress CS activation (Liao, W.-C., Haimovitz-Friedman, A., Persaud, R., McLoughlin, M., Ehleiter, D., Zhang, N., Gatei, M., Lavin, M., Kolesnick, R., and Fuks, Z. (1999) J. Biol. Chem. 274, 17908-17917). Gel shift analysis in LNCaP and CWR22-Rv1 cells demonstrated a significant reduction in DNA binding of the Sp1 transcription factor to the ATM promoter, and quantitative reverse transcription-PCR showed a 50% reduction of ATM mRNA between 8 and 16 h of TPA treatment, indicating that TPA inhibits ATM transcription. Furthermore, treatment of LNCaP, CWR22-Rv1, PC-3, and DU-145 human prostate cells with antisense-ATM oligonucleotides, which markedly reduced cellular ATM levels, significantly enhanced radiation-induced CS activation and apoptosis, leading to apoptosis at doses as a low as 1 gray. These data suggest that the CS pathway initiates a generic mode of radiation-induced apoptosis in human prostate cancer cells, regulated by a suppressive function of ATM, and that ATM might represent a potential target for pharmacologic inactivation with potential clinical applications in human prostate cancer. PMID:15837784

Truman, Jean-Philip; Gueven, Nuri; Lavin, Martin; Leibel, Steven; Kolesnick, Richard; Fuks, Zvi; Haimovitz-Friedman, Adriana

2007-01-01

340

Radiation-induced alterations of histone post-translational modification levels in lymphoblastoid cell lines  

PubMed Central

Background Radiation-induced alterations in posttranslational histone modifications (PTMs) may affect the cellular response to radiation damage in the DNA. If not reverted appropriately, altered PTM patterns may cause long-term alterations in gene expression regulation and thus lead to cancer. It is therefore important to characterize radiation-induced alterations in PTM patterns and the factors affecting them. Methods A lymphoblastoid cell line established from a normal donor was used to screen for alterations in methylation levels at H3K4, H3K9, H3K27, and H4K20, as well as acetylation at H3K9, H3K56, H4K5, and H4K16, by quantitative Western Blot analysis at 15 min, 1 h and 24 h after irradiation with 2 Gy and 10 Gy. The variability of alterations in acetylation marks was in addition investigated in a panel of lymphoblastoid cell lines with differing radiosensitivity established from lung cancer patients. Results The screening procedure demonstrated consistent hypomethylation at H3K4me3 and hypoacetylation at all acetylation marks tested. In the panel of lymphoblastoid cell lines, however, a high degree of inter-individual variability became apparent. Radiosensitive cell lines showed more pronounced and longer lasting H4K16 hypoacetylation than radioresistant lines, which correlates with higher levels of residual ?-H2AX foci after 24 h. Conclusion So far, the factors affecting extent and duration of radiation-induced histone alterations are poorly defined. The present work hints at a high degree of inter-individual variability and a potential correlation of DNA damage repair capacity and alterations in PTM levels. PMID:24406105

2014-01-01

341

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

342

Radiation-induced formation, annealing and ordering of voids in crystals: Theory and experiment  

NASA Astrophysics Data System (ADS)

Void ordering has been observed in very different radiation environments ranging from metals to ionic crystals bombarded with energetic particles. The void ordering is often accompanied by a saturation of the void swelling with increasing irradiation dose, which makes an understanding of the underlying mechanisms to be both of scientific significance and of practical importance for nuclear engineering. We show that both phenomena can be explained by the original mechanism based on the anisotropic energy transfer provided by self-focusing discrete breathers or quodons (energetic, mobile, highly localized lattice solitons that propagate great distances along close-packed crystal directions). The interaction of quodons with voids can result in radiation-induced “annealing” of selected voids, which results in the void ordering under special irradiation conditions. We observe experimentally radiation-induced void annealing by lowering the irradiation temperature of nickel and copper samples pre-irradiated to produce voids or gas bubbles. The bulk recombination of Frenkel pairs increases with decreasing temperature resulting in suppression of the production of freely migrating vacancies (the driving force of the void growth). On the other hand, the rate of radiation-induced vacancy emission from voids due to the void interaction with quodons remains essentially unchanged, which results in void dissolution. The experimental data on the void shrinkage and void lattice formation obtained for different metals and irradiating particles are explained by the present model assuming the quodon propagation length to be in the micron range, which is consistent with independent data on the irradiation-induced diffusion of interstitial ions in austenitic stainless steel.

Dubinko, V. I.; Guglya, A. G.; Donnelly, S. E.

2011-07-01

343

Efficacy of radioprotection in the prevention of radiation-induced craniofacial bone growth inhibition.  

PubMed

It has been reported that radiotherapy-induced craniofacial deformities can occur in 66 to 100 percent of survivors of childhood head and neck cancers. Recent interest in the effectiveness of radioprotectors in the protection of normal tissue against radiation injury led us to investigate a possible role of radioprotection in the prevention of radiation-induced craniofacial bone growth inhibition. Therefore, the objective of this study was to use the radioprotective agent amifostine (Ethyol, WR-2721) as a probe to determine the effectiveness of radioprotection in the prevention of radiation-induced craniofacial bone growth inhibition after single-dose orthovoltage radiation to the infant rabbit orbital-zygomatic complex. Seven-week-old male New Zealand white rabbits were randomized into three groups (n = 10 each): group 1, 0 Gy (sham radiation); group 2, 35-Gy single-dose orthovoltage radiation; and group 3, 35-Gy single-dose orthovoltage radiation and amifostine (300 mg/kg intravenously, given 20 minutes before radiation). Serial radiographs and computed tomographic scans were obtained for cephalometric analysis, bone volume, and bone density measurements until skeletal maturity at 21 weeks. Significant (p < 0.05) reductions in orbital-zygomatic complex linear bone growth, bone volume, and bone density were observed after 35-Gy radiation compared with nonirradiated controls. No significant differences were noted between groups in cephalometric analysis of the nontreated (nonirradiated) left orbital-zygomatic complex, indicating no crossover effect from the radiation beam. However, pretreatment with amifostine, 20 minutes before 35-Gy radiation, resulted in significant (p < 0.05) preservation of linear bone growth, bone volume, and bone mineral density in the rabbit orbital-zygomatic complex compared with controls. This study demonstrated for the first time the effectiveness of a radioprotector in the prevention of radiation-induced craniofacial bone growth inhibition, and it paves the way for investigation into the pathogenic mechanism and prevention of radiotherapy-induced craniofacial deformities. PMID:11964983

Forrest, Christopher R; O'Donovan, David A; Yeung, Ivan; Zeman, Vlado; La Scala, Giorgio; Neligan, Peter C; Pang, Cho Y

2002-04-01

344

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

SciTech Connect

Highlights: Black-Right-Pointing-Pointer We examine how radiation affects the expression level and signal pathway of collagen. Black-Right-Pointing-Pointer TGF-{beta}1 mRNA is elevated earlier than those of collagen genes after irradiation. Black-Right-Pointing-Pointer Smad pathway mediates the expression of collagen in radiation induced fibrosis. Black-Right-Pointing-Pointer MAPK pathways are not affected in the expression of collagen after irradiation. -- Abstract: Radiation induced fibrosis occurs following a therapeutic or accidental radiation exposure in normal tissues. Tissue fibrosis is the excessive accumulation of collagen and other extracellular matrix components. This study investigated how ionizing radiation affects the expression level and signal pathway of type I collagen. Real time RT-RCR showed that both {alpha}1and {alpha}2 chain of type I collagen mRNA were elevated from 48 h after irradiation with 10 Gy in NIH3T3 cells. The relative luciferase activities of both genes and type I collagen marker were elevated at 72 h. TGF-{beta}1 mRNA was elevated earlier than those of type I collagen genes. A Western blot analysis showed the elevation of Smad phosphorylation at 72 h. Conversely, treatment with TGF-{beta} receptor inhibitor inhibited the mRNA and relative luciferase activity of type I collagen. The phosphorylation of Smad was repressed with the inhibitor, and the luciferase activity was cancelled using a mutant construct of Smad binding site of {alpha}2(I) collagen gene. However, the MAPK pathways, p38, ERK1/2 and JNK, were not affected with specific inhibitors or siRNA. The data showed that the Smad pathway mediated the expression of type I collagen in radiation induced fibrosis.

Yano, Hiroyuki [Department of Matrix Medicine, Oita University, 1-1 Idaigaoka Hasama-machi, Yufu, Oita 879-5593 (Japan) [Department of Matrix Medicine, Oita University, 1-1 Idaigaoka Hasama-machi, Yufu, Oita 879-5593 (Japan); Division of Radioisotope Research, Department of Research Support, Research Promotion Project, Oita University, 1-1 Idaigaoka Hasama-machi, Yufu, Oita 879-5593 (Japan); Hamanaka, Ryoji; Nakamura, Miki [Cell Biology, Faculty of Medicine, Oita University, 1-1 Idaigaoka Hasama-machi, Yufu, Oita 879-5593 (Japan)] [Cell Biology, Faculty of Medicine, Oita University, 1-1 Idaigaoka Hasama-machi, Yufu, Oita 879-5593 (Japan); Sumiyoshi, Hideaki; Matsuo, Noritaka [Department of Matrix Medicine, Oita University, 1-1 Idaigaoka Hasama-machi, Yufu, Oita 879-5593 (Japan)] [Department of Matrix Medicine, Oita University, 1-1 Idaigaoka Hasama-machi, Yufu, Oita 879-5593 (Japan); Yoshioka, Hidekatsu, E-mail: hidey@oita-u.ac.jp [Department of Matrix Medicine, Oita University, 1-1 Idaigaoka Hasama-machi, Yufu, Oita 879-5593 (Japan)] [Department of Matrix Medicine, Oita University, 1-1 Idaigaoka Hasama-machi, Yufu, Oita 879-5593 (Japan)

2012-02-17

345

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.

346

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

347

Observation of linear-polarization-sensitivity in the microwave-radiation-induced magnetoresistance oscillations  

SciTech Connect

We examine the linear polarization sensitivity of the radiation- induced magneto-resistance oscillations by investigating the effect of rotating in-situ the electric field of linearly polarized microwaves relative to the current, in the GaAs/AlGaAs system. We find that the frequency and the phase of the photo-excited magneto-resistance oscillations are insensitive to the polarization. On the other hand, the amplitude of the resistance oscillations are strongly sensitive to the relative orientation between the microwave antenna and the current-axis in the specimen.

Mani, R. G.; Ramanayaka, A. N. [Department of Physics and Astronomy, Georgia State University, Atlanta, Georgia 30303 (United States); Wegscheider, W. [Laboratorium für Festkörperphysik, ETH Zürich, CH-8093 Zürich (Switzerland)

2013-12-04

348

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

NASA Astrophysics Data System (ADS)

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

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

349

Bias control of long term radiation-induced transients in GaAs MESFETS  

SciTech Connect

The effect of guard ring bias and of self bias on radiation-induced long term transients in GaAs D-MESFETs has been measured for dose rates up to 10/sup 12/ Rads(GaAs)/s. Results are presented for ohmic and for Schottky guard rings with the substrate-bottom grounded as well as separately biased. Significant reduction in recovery times and transient amplitudes suggests that these are viable radiation hardening techniques allowing less dependence on the device fabrication process.

Casey, R.H.; Herman, W.N.; LaCombe, D.J.; Ragonese, L.J.; Immorlica, A.; Anderson, W.T.

1988-12-01

350

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

SciTech Connect

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

Lee, Victor H.F., E-mail: vhflee@hku.hk [Department of Clinical Oncology, University of Hong Kong, Queen Mary Hospital (Hong Kong); Ng, Sherry C.Y.; Leung, T.W.; Au, Gordon K.H.; Kwong, Dora L.W. [Department of Clinical Oncology, University of Hong Kong, Queen Mary Hospital (Hong Kong)] [Department of Clinical Oncology, University of Hong Kong, Queen Mary Hospital (Hong Kong)

2012-09-01

351

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

NASA Astrophysics Data System (ADS)

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

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

2006-01-01

352

Radiation-induced "zero-resistance state" and the photon-assisted transport.  

PubMed

We demonstrate that the radiation-induced "zero-resistance state" observed in a two-dimensional electron gas is a result of the nontrivial structure of the density of states of the systems and the photon-assisted transport. A toy model of a quantum tunneling junction with oscillatory density of states in leads catches most of the important features of the experiments. We present a generalized Kubo-Greenwood conductivity formula for the photon-assisted transport in a general system and show essentially the same nature of the transport anomaly in a uniform system. PMID:14525265

Shi, Junren; Xie, X C

2003-08-22

353

The application of radiation-induced processed copolymers to biocatalysis immobilisation  

NASA Astrophysics Data System (ADS)

In this paper, some of the work carried out at our laboratories on the immobilisation of biocatalysts onto graft copolymers prepared by radiation induced procedures is reported. The graft copolymers used were based either on hydrophilic natural polymer (agar) or on hydrophobic (polyethylene) supports. The comonomers grafted branches include poly(hydroxyethyl methacrylate) and poly(hydroxyethyl methacrylate) crosslinked with trimethylpropane triacrylata (TMPTA). The suitability of these graft copolymers for immobilising ?-chymotrypsin, glucose oxidase and trypsin was assessed by determining the amount of biocatalysts coupled to the support and its retention of activity. The Michaelis Mentan constants (K M) for some of the immobilised enzymes were determined.

de Silva, M. Alves; Beddows, C. G.; Gil, M. H.; Guthrie, J. T.; Guiomar, A. J.; Kotov, S.; Piedade, A. P.

354

Resistance of radiation-induced tropical wood-polymer composites to fungal degradation  

NASA Astrophysics Data System (ADS)

The resistance of six tropical hardwoods to fungal degradation by two wild-type strains of Phanerochaete chrysosporium Burdsall was investigated using vermiculite burial and wood-block weight loss techniques. Radiation-induced wood-polymer composites (WPC), based on two hardwoods Ramin and Rubber-wood with methyl methacrylate, were prepared, and samples were also exposed to the wood-rotting fungus. A significant improvement in resistance to fungal decay was observed in the WPC. Scanning-electron micrographs of the two woods and their composites after fungal degradation are presented and discussed.

Chia, L. H. L.; Lim, V. S. L.; Yap, M. G. S.

355

Effect of bentonite on radiation induced dissolution of UO2 in an aqueous system  

NASA Astrophysics Data System (ADS)

In order to elucidate the impact of bentonite on the process of radiation induced oxidative dissolution of UO2 in an aqueous system, the dissolution of U(VI) and consumption of H2O2 over time has been studied. In addition, ?-irradiation experiments were performed to study a more relevant and complex system, serving as a comparison with the previously stated system. In both cases, the experiments revealed that the presence of bentonite in water could either delay or prevent in part the release of uranium to the environment. The cause is mainly attributed to the scavenging of radiolytic oxidants rather than to the adsorption of uranium onto bentonite.

Barreiro Fidalgo, Alexandre; Sundin, Sara; Jonsson, Mats

2014-04-01

356

Late-onset radiation-induced vasculopathy and stroke in a child with medulloblastoma.  

PubMed

We report a case of a 15-year-old boy who presented to our institution with left-sided weakness and slurred speech. He had a history of medulloblastoma diagnosed at 3 years of age, status postsurgical resection and craniospinal radiation. Magnetic resonance imaging (MRI) of brain revealed a right paramedian pontine infarction, suspected secondary to late-onset radiation-induced vasculopathy of the vertebrobasilar system. Radiation to the brain is associated with increased incidence of ischemic stroke. Clinicians should have a high index of suspicion for stroke when these patients present with new neurologic symptoms. PMID:25015672

Bansal, Lalit R; Belair, Jeffrey; Cummings, Dana; Zuccoli, Giulio

2015-05-01

357

Accumulation of radiation-induced charge in MNOS structures with different oxide thicknesses  

SciTech Connect

The authors attempt to answer questions regarding the dosimetry of x-ray radiation sources, especially in the region of high exposure doses, using silicon nitride. SiO/sub 2/ was obtained by thermal oxidation in dry oxygen or in a mixture of oxygen and argon. Silicon nitride was obtained by ammonolysis of silicon tetrachloride. Aluminum was used for the gate. The magnitude of the radiation-induced space charge was determined from the shift in the flat-band voltage on the high-frequency volt-faraday curves.

Gurtov, V.A.; Evdokimov, V.D.; Nazarov, A.I.; Khrustalev, V.A.

1986-05-01

358

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. PMID:19747571

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

2009-01-01

359

Human amniotic epithelial cell transplantation for the repair of injured brachial plexus nerve: evaluation of nerve viscoelastic properties  

PubMed Central

The transplantation of embryonic stem cells can effectively improve the creeping strength of nerves near an injury site in animals. Amniotic epithelial cells have similar biological properties as embryonic stem cells; therefore, we hypothesized that transplantation of amniotic epithelial cells can repair peripheral nerve injury and recover the creeping strength of the brachial plexus nerve. In the present study, a brachial plexus injury model was established in rabbits using the C6 root avulsion method. A suspension of human amniotic epithelial cells was repeatedly injected over an area 4.0 mm lateral to the cephal and caudal ends of the C6 brachial plexus injury site (1 × 106 cells/mL, 3 ?L/injection, 25 injections) immediately after the injury. The results showed that the decrease in stress and increase in strain at 7,200 seconds in the injured rabbit C6 brachial plexus nerve were mitigated by the cell transplantation, restoring the viscoelastic stress relaxation and creep properties of the brachial plexus nerve. The forepaw functions were also significantly improved at 26 weeks after injury. These data indicate that transplantation of human amniotic epithelial cells can effectively restore the mechanical properties of the brachial plexus nerve after injury in rabbits and that viscoelasticity may be an important index for the evaluation of brachial plexus injury in animals.

Jin, Hua; Yang, Qi; Ji, Feng; Zhang, Ya-jie; Zhao, Yan; Luo, Min

2015-01-01

360

Human amniotic epithelial cell transplantation for the repair of injured brachial plexus nerve: evaluation of nerve viscoelastic properties.  

PubMed

The transplantation of embryonic stem cells can effectively improve the creeping strength of nerves near an injury site in animals. Amniotic epithelial cells have similar biological properties as embryonic stem cells; therefore, we hypothesized that transplantation of amniotic epithelial cells can repair peripheral nerve injury and recover the creeping strength of the brachial plexus nerve. In the present study, a brachial plexus injury model was established in rabbits using the C6 root avulsion method. A suspension of human amniotic epithelial cells was repeatedly injected over an area 4.0 mm lateral to the cephal and caudal ends of the C6 brachial plexus injury site (1 × 10(6) cells/mL, 3 ?L/injection, 25 injections) immediately after the injury. The results showed that the decrease in stress and increase in strain at 7,200 seconds in the injured rabbit C6 brachial plexus nerve were mitigated by the cell transplantation, restoring the viscoelastic stress relaxation and creep properties of the brachial plexus nerve. The forepaw functions were also significantly improved at 26 weeks after injury. These data indicate that transplantation of human amniotic epithelial cells can effectively restore the mechanical properties of the brachial plexus nerve after injury in rabbits and that viscoelasticity may be an important index for the evaluation of brachial plexus injury in animals. PMID:25883625

Jin, Hua; Yang, Qi; Ji, Feng; Zhang, Ya-Jie; Zhao, Yan; Luo, Min

2015-02-01

361

Incidence of intravenous contrast extravasation: increased risk for patients with deep brachial catheter placement from the emergency department.  

PubMed

Deep brachial intravenous catheter (IV) placement can be performed in emergency department patients with difficult vascular access, but the safety of deep brachial IV for iodinated contrast administration has not been assessed. This study compares the relative risk for extravasation of deep brachial IV compared with antecubital IV during power injected computed tomography (CT) examinations. A departmental practice quality improvement was performed to assess the rate of IV extravasation for all CT examinations during a 1 year period. De-identified data was analyzed with a waiver of informed consent to identify the rate and relative risk of iodinated contrast extravasation by catheter type. A total of 10,750 injections were performed, with 82 extravasation events (0.8 %). There were 51 extravasations of antecubital IV from approximately 8,599 placed (0.6 %). For 123 deep brachial IV placed, there were eight extravasations (6.5 %). The relative risk of a deep brachial IV extravasation was 9.4 compared to 0.4 for antecubital placement. Deep brachial IV demonstrated a markedly higher rate of contrast extravasation than antecubital IV. For power injected iodinated contrast administration, it is recommended to avoid the use of deep brachial IV whenever possible. PMID:24395398

Hardie, Andrew D; Kereshi, Borko

2014-06-01

362

Transposed brachial-basilic arteriovenous fistulas versus prosthetic upper limb grafts: A meta-analysis  

Microsoft Academic Search

BackgroundControversy exists regarding the best type of arteriovenous (AV) fistula to be formed in secondary and tertiary access procedures when primary fistulas have failed. This meta-analysis aimed to compare transposed brachial-basilic AV fistulas (BBAVFs) with upper limb AV prosthetic grafts.

M. K. Lazarides; G. S. Georgiadis; C. P. Papasideris; G. Trellopoulos; V. D. Tzilalis

2008-01-01

363

Cost analysis of brachial plexus injuries: variability of compensation by insurance companies before and after surgery.  

PubMed

Traumatic paralysis of the brachial plexus is an extremely disabling pathology. The type of trauma most frequently suffered by this group of patients is due to motorcycle injuries. It therefore affects a population of young patients. In the majority of cases, these patients receive compensation for permanent damage from insurance companies. Surgery of the brachial plexus enables various forms of functional recovery, depending on the number of roots of the brachial plexus involved in the injury. The aim of this study is to compare the functional deficit and the extent of the related compensation before and after surgical intervention, and to evaluate the saving in economic terms (understood as the cost of compensation paid by insurance companies) obtainable through surgical intervention. The authors analysed the functional recovery obtained through surgery in 134 patients divided into 4 groups on the basis of the number of injured roots. The levels of compensation payable to the patient before surgical intervention, and 3 years after, were then compared. The results showed that the saving obtainable through surgical treatment of brachial plexus injuries may exceed 65% of the economic value of the compensation that would have been attributable to the same patients if they had not undergone surgical treatment. PMID:24777457

Felici, N; Zaami, S; Ciancolini, G; Marinelli, E; Tagliente, D; Cannatà, C

2014-04-01

364

Estrogen Replacement and Brachial Artery Flow-Mediated Vasodilation in Older Women  

Microsoft Academic Search

It remains unclear whether estrogen therapy (with or without progestin) improves endothelial function in older postmenopausal women with or at risk for coronary heart disease. To address this issue, we analyzed brachial artery flow-mediated vasodilation in the Cardiovascular Health Study, a longitudinal study of cardiovascular risk factors in subjects over 65 years of age. At the tenth annual Cardiovascular Health

David M. Herrington; Mark A. Espeland; John R. Crouse III; Julia Robertson; Ward A. Riley; Mary Ann McBurnie; Gregory L. Burke

365

Ultrasound-guided infraclavicular brachial plexus block: An alternative technique to anatomical landmark-guided approaches  

Microsoft Academic Search

Background and Objectives: Infraclavicular brachial plexus block has been used less than other approaches because of its less uniform landmarks and the necessity of a longer needle, which increases the patient's discomfort. To overcome these drawbacks, we applied ultrasound guidance to infraclavicular approach and prospectively evaluated its feasibility and usefulness in 60 patients undergoing upper extremity surgery. Methods: A 7.0-MHz

Chiyo Ootaki; Hideaki Hayashi; Masaru Amano

2000-01-01

366

Isolated Peripheral Nerve Lesions of the Brachial Plexus Affecting the Shoulder Joint  

Microsoft Academic Search

Shoulder pain, weakness, and instability are common findings of nerve entrapment and traumatic and inflammatory le- sions of the brachial plexus. These disorders can be properly di- agnosed with careful clinical examination and electrophysiologic testing. An understanding of the kinesiology of muscles acting on the scapula aids in the diagnosis of patients presenting with muscle atrophy and scapular winging. This

ERNEST J. GENTCHOS

367

Obstetric Brachial Plexus Palsy in Newborn Babies of Diabetic and Non-Diabetic Mothers  

Microsoft Academic Search

Compared to non-diabetic mothers, diabetic mothers are known to deliver larger babies who are at higher risk for shoulder dystocia and obstetric brachial plexus palsy. The intrapartum forces applied during delivery of larger babies are expected to be higher. Hence, the chances of these babies for good spontaneous recovery are expected to be lower; and this is a generally believed

M. M. Al-Qattan; A. A. F. El-Sayed; A. Y. Al-Zahrani; S. A. Al-Mutairi; M. S. Al-Harbi; A. M. Al-Mutairi; F. S. Al-Kahtani

2010-01-01

368

Luxation de l’épaule compliquée de paralysie du plexus brachial  

PubMed Central

Les auteurs rapportent l'observation d'une paralysie totale du plexus brachial survenue trois mois après un épisode de luxation antéro-interne sous coracoïdienne associée à une fracture du trochiter chez une patiente âgée de 88 ans. PMID:25426187

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

2014-01-01

369

The effect of perinatal brachial plexus lesion on upper limb development  

PubMed Central

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

2014-01-01

370

TENDON TRANSFER TO RECONSTRUCT WRIST EXTENSION IN CHILDREN WITH OBSTETRIC BRACHIAL PLEXUS PALSY  

Microsoft Academic Search

This study reports on 20 children with obstetric brachial plexus palsy who underwent a tendon transfer to reconstruct wrist extension. The mean age at the time of tendon transfer was 8 years. There were seven patients with Erb's palsy and the remaining 13 had total palsy. The flexor carpi ulnaris was utilized 15 times and the flexor carpi radialis five

M. M. Al-QATTAN

2003-01-01

371

A Fourth Type of Brachial Plexus Lesion: The Intermediate (C7) Palsy  

Microsoft Academic Search

A new type of brachial plexus lesion has been defined to be added to the classical types, i.e. the upper (Duchenne Erb), the lower (Dejerine Klumpke) and the total type. This new type is the intermediate palsy. The lesion is a partial involvement of the plexus, the predominant lesion of which involves C7 with a variable involvement of the upper

G. A. BRUNELLI; G. R. BRUNELLI

1991-01-01

372

Accidental contact burns of the upper limb in children with obstetric brachial plexus injury  

Microsoft Academic Search

The denervated limb of the child with obstetrical brachial plexus injury is theoretically at risk of contact burns. A prospective study was designed to document the incidence and clinical presentation of these burn injuries in a series of 127 birth palsy cases. The study group included 90 Erb's and 37 total plexus palsy cases. Accidental burns occurred in 11% of

M. M. Al-Qattan

1999-01-01

373

Development of a novel experimental rat model for neonatal pre-ganglionic upper brachial plexus injury  

Microsoft Academic Search

A neonatal upper brachial plexus injury, referred to as Erb's palsy, is a serious obstetric problem. Some surgical methods are used to treat this injury, but they are inadequate. To seek new treatments for Erb's palsy, we used a model for cervical preganglionic root transection in neonate rats and evaluated the behavioral and histological compatibility of this model with Erb's

Hidenobu Ochiai; Tomoaki Ikeda; Kenichi Mishima; Tetsuya Yoshikawa; Naoya Aoo; Katsunori Iwasaki; Michihiro Fujiwara; Tsuyomu Ikenoue; Shinichi Nakano; Shinichiro Wakisaka

2002-01-01

374

Robot-Assisted Surgery of the Shoulder Girdle and Brachial Plexus  

PubMed Central

New developments in the surgery of the brachial plexus include the use of less invasive surgical approaches and more precise techniques. The theoretical advantages of the use of robotics versus endoscopy are the disappearance of physiological tremor, three-dimensional vision, high definition, magnification, and superior ergonomics. On a fresh cadaver, a dissection space was created and maintained by insufflation of CO2. The supraclavicular brachial plexus was dissected using the da Vinci robot (Intuitive Surgical, Sunnyvale, CA). A segment of the C5 nerve root was grafted robotically. A series of eight clinical cases of nerve damage around the shoulder girdle were operated on using the da Vinci robot. The ability to perform successful microneural repair was confirmed in both the authors' clinical and experimental studies, but the entire potential of robotically assisted microneural surgery was not realized during these initial cases because an open incision was still required. Robotic-assisted surgery of the shoulder girdle and brachial plexus is still in its early stages. It would be ideal to have even finer and more suitable instruments to apply fibrin glue or electrostimulation in nerve surgery. Nevertheless, the prospects of minimally invasive techniques would allow acute and subacute surgical approach of traumatic brachial plexus palsy safely, without significant and cicatricial morbidity. PMID:24872778

Facca, Sybille; Hendriks, Sarah; Mantovani, Gustavo; Selber, Jesse C.; Liverneaux, Philippe

2014-01-01

375

Supranormal ankle brachial index is associated with a favorable exercise blood pressure response  

Microsoft Academic Search

The Ankle Brachial Index (ABI) is an established diagnostic test for peripheral arterial disease. Howerver, the significance of an ABI greater than 1.0 has been controversial, specifically in patients with diabetes mellitus or individuals evaluated in a primary cardiovascular prevention cohort. We hypothesized that high ABI values, usually considered to represent a noncompliant arterial circulation, would be associated with an

Gardar Sigurdsson; Daniel A. Duprez; Alan T. Hirsch; Natalia Florea; Lynn Hoke; Jay N. Cohn

2003-01-01

376

Brachial plexus anesthesia: A review of the relevant anatomy, complications, and anatomical variations.  

PubMed

The trend towards regional anesthesia began in the late 1800s when William Halsted and Richard Hall experimented with cocaine as a local anesthetic for upper and lower limb procedures. Regional anesthesia of the upper limb can be achieved by blocking the brachial plexus at varying stages along the course of the trunks, divisions, cords and terminal branches. The four most common techniques used in the clinical setting are the interscalene block, the supraclavicular block, the infraclavicular block, and the axillary block. Each approach has its own unique set of advantages and indications for use. The supraclavicular block is most effective for anesthesia of the mid-humerus and below. Infraclavicular blocks are useful for procedures requiring continuous anesthesia. Axillary blocks provide effective anesthesia distal to the elbow, and interscalene blocks are best suited for the shoulder and proximal upper limb. The two most common methods for localizing the appropriate nerves for brachial plexus blocks are nerve stimulation and ultrasound guidance. Recent literature on brachial plexus blocks has largely focused on these two techniques to determine which method has greater efficacy. Ultrasound guidance has allowed the operator to visualize the needle position within the musculature and has proven especially useful in patients with anatomical variations. The aim of this study is to provide a review of the literature on the different approaches to brachial plexus blocks, including the indications, techniques, and relevant anatomical variations associated with the nerves involved. PMID:23959836

Mian, Asma; Chaudhry, Irfan; Huang, Richard; Rizk, Elias; Tubbs, R Shane; Loukas, Marios

2014-03-01

377

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

ERIC Educational Resources Information Center

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

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

2004-01-01

378

Large brachial and common carotid artery diameter in postmenopausal women with carotid atherosclerosis  

Microsoft Academic Search

Background and purposeIt is recognized that arteries can enlarge to compensate atherosclerosis. The role of diameter enlargement of unaffected arteries is not well known. We hypothesized that brachial and common carotid arteries diameters were larger in subjects with carotid atherosclerosis compared to subjects without these lesions.

Tiziana Montalcini; Gaetano Gorgone; Carmine Gazzaruso; Giorgio Sesti; Francesco Perticone; Arturo Pujia

2008-01-01

379

Preclinical evaluation of erythropoietin administration in a model of radiation-induced kidney dysfunction  

SciTech Connect

Purpose: To test whether the clinically available growth factor erythropoietin (EPO) influences radiation-induced normal-tissue damage in a model of kidney dysfunction. Methods: Animal experiments were conducted to test the role of EPO administration in a C3H mouse model of unilateral kidney irradiation with 6, 8, and 10 Gy and to assess the effects of 2 different dose levels of EPO. The kidney function was assessed before radiotherapy, as well as 19, 25, 31, and 37 weeks thereafter by means of {sup 99m}Tc-dimercaptosuccinat scans (static scintigraphy). Results: Concomitant EPO administration significantly increased the degree of radiation-induced kidney dysfunction. A dose of 2,000 IU/kg body weight per injection tended to cause more damage than the lower dose of 500 IU/kg. Conclusion: Administration of growth factors concomitant to radiotherapy might modify the development of kidney dysfunction. Although insulin-like growth factor-1 has previously been shown to protect the kidney, such an effect could not be demonstrated for EPO. The latter agent even increased the development of nephropathy.

Andratschke, Nicolaus [Department of Radiation Oncology, Klinikum rechts der Isar, Technical University of Munich, Munich (Germany); Schnaitera, Andrea [Department of Radiation Oncology, Klinikum rechts der Isar, Technical University of Munich, Munich (Germany); Weber, Wolfgang A. [Department of Molecular and Medical Pharmacology, Ahmanson Biological Imaging Center, The University of California, Los Angeles, David Geffen School of Medicine, Los Angeles, CA (United States); Caia, Lu [Department of Radiation Oncology, Klinikum rechts der Isar, Technical University of Munich, Munich (Germany); Schill, Sabine [Department of Radiation Oncology, Klinikum rechts der Isar, Technical University of Munich, Munich (Germany); Wiedenmann, Nicole [Department of Experimental Radiation Oncology, University of Texas M.D. Anderson Cancer Center, Houston, TX (United States); Schwaiger, Markus [Department of Nuclear Medicine, Klinikum rechts der Isar, Technical University of Munich, Munich (Germany); Molls, Michael [Department of Radiation Oncology, Klinikum rechts der Isar, Technical University of Munich, Munich (Germany); Nieder, Carsten [Department of Radiation Oncology, Klinikum rechts der Isar, Technical University of Munich, Munich (Germany)]. E-mail: cnied@hotmail.com

2006-04-01

380

Blockade of TLR3 protects mice from lethal radiation-induced gastrointestinal syndrome.  

PubMed

High-dose ionizing radiation induces severe DNA damage in the epithelial stem cells in small intestinal crypts and causes gastrointestinal syndrome (GIS). Although the tumour suppressor p53 is a primary factor inducing death of crypt cells with DNA damage, its essential role in maintaining genome stability means inhibiting p53 to prevent GIS is not a viable strategy. Here we show that the innate immune receptor Toll-like receptor 3 (TLR3) is critical for the pathogenesis of GIS. Tlr3(-/-) mice show substantial resistance to GIS owing to significantly reduced radiation-induced crypt cell death. Despite showing reduced crypt cell death, p53-dependent crypt cell death is not impaired in Tlr3(-/-) mice. p53-dependent crypt cell death causes leakage of cellular RNA, which induces extensive cell death via TLR3. An inhibitor of TLR3-RNA binding ameliorates GIS by reducing crypt cell death. Thus, we propose blocking TLR3 activation as a novel approach to treat GIS. PMID:24637670

Takemura, Naoki; Kawasaki, Takumi; Kunisawa, Jun; Sato, Shintaro; Lamichhane, Aayam; Kobiyama, Kouji; Aoshi, Taiki; Ito, Junichi; Mizuguchi, Kenji; Karuppuchamy, Thangaraj; Matsunaga, Kouta; Miyatake, Shoichiro; Mori, Nobuko; Tsujimura, Tohru; Satoh, Takashi; Kumagai, Yutaro; Kawai, Taro; Standley, Daron M; Ishii, Ken J; Kiyono, Hiroshi; Akira, Shizuo; Uematsu, Satoshi

2014-01-01

381

Blockade of TLR3 protects mice from lethal radiation-induced gastrointestinal syndrome  

PubMed Central

High-dose ionizing radiation induces severe DNA damage in the epithelial stem cells in small intestinal crypts and causes gastrointestinal syndrome (GIS). Although the tumour suppressor p53 is a primary factor inducing death of crypt cells with DNA damage, its essential role in maintaining genome stability means inhibiting p53 to prevent GIS is not a viable strategy. Here we show that the innate immune receptor Toll-like receptor 3 (TLR3) is critical for the pathogenesis of GIS. Tlr3?/? mice show substantial resistance to GIS owing to significantly reduced radiation-induced crypt cell death. Despite showing reduced crypt cell death, p53-dependent crypt cell death is not impaired in Tlr3?/? mice. p53-dependent crypt cell death causes leakage of cellular RNA, which induces extensive cell death via TLR3. An inhibitor of TLR3–RNA binding ameliorates GIS by reducing crypt cell death. Thus, we propose blocking TLR3 activation as a novel approach to treat GIS. PMID:24637670

Takemura, Naoki; Kawasaki, Takumi; Kunisawa, Jun; Sato, Shintaro; Lamichhane, Aayam; Kobiyama, Kouji; Aoshi, Taiki; Ito, Junichi; Mizuguchi, Kenji; Karuppuchamy, Thangaraj; Matsunaga, Kouta; Miyatake, Shoichiro; Mori, Nobuko; Tsujimura, Tohru; Satoh, Takashi; Kumagai, Yutaro; Kawai, Taro; Standley, Daron M.; Ishii, Ken J.; Kiyono, Hiroshi; Akira, Shizuo; Uematsu, Satoshi

2014-01-01

382

Rejoining and misrejoining of radiation-induced chromatin breaks. III. Hypertonic treatment  

NASA Technical Reports Server (NTRS)

It has been shown that treatment in anisotonic medium modifies rejoining of radiation-induced breaks in interphase chromosomes. In previous work, we have demonstrated that formation of exchanges in human lymphocytes has a slow component (half-time of 1-2 h), but a fraction of exchanges are also observed in samples assayed soon after exposure. In this paper we studied the effect of hypertonic treatment on rejoining and misrejoining of radiation-induced breaks using fluorescence in situ hybridization of prematurely condensed chromosomes in human lymphocytes. Isolated lymphocytes were irradiated with 7 Gy gamma rays, fused to mitotic hamster cells and incubated in hypertonic solution (0.5 M NaCl) for the period normally allowed for interphase chromosome condensation to occur. The data from hypertonic treatment experiments indicate the presence of a class of interphase chromosome breaks that rejoin and misrejoin very quickly (half-time of 5-6 min). The fast misrejoining of these lesions is considered to be responsible for the initial level of exchanges which we reported previously. No significant effect of hypertonic treatment on the yield of chromosome aberrations scored at the first postirradiation mitosis was detected.

Durante, M.; George, K.; Wu, H. L.; Yang, T. C.

1998-01-01

383

Radiation-induced complications in prostate cancer patients treated with radiotherapy  

NASA Astrophysics Data System (ADS)

The purpose of the study is to determine the relationship between radiation-induced complications with dosimetric and radiobiological parameters for prostate cancer patients that underwent the conformal radiotherapy treatment. 17 prostate cancer patients that have been treated with conformal radiotherapy were retrospectively analysed. The dosimetric data was retrieved in the form of dose-volume histogram (DVH) from Radiotherapy Treatment Planning System. The DVH was utilised to derived Normal Tissue Complication Probability (NTCP) in radiobiological data. Follow-up data from medical records were used to grade the occurrence of acute gastrointestinal (GI) and genitourinary (GU) complications using Radiation Therapy Oncology Group (RTOG) scoring system. The chi-square test was used to determine the relationship between radiation-induced complication with dosimetric and radiobiological parameters. 8 (47%) and 7 (41%) patients were having acute GI and GU complications respectively. The acute GI complication can be associated with V60rectum, rectal mean dose and NTCPrectum with p-value of 0.016, 0.038 and 0.049 respectively. There are no significant relationships of acute GU complication with dosimetric and radiobiological variables. Further study can be done by increase the sample size and follow up duration for deeper understanding of the factors that effecting the GU and GI complication in prostate cancer radiotherapy.

Azuddin, A. Yusof; Rahman, I. Abdul; Siah, N. J.; Mohamed, F.; Saadc, M.; Ismail, F.

2014-09-01

384

Radiation-induced complications in prostate cancer patients treated with radiotherapy  

SciTech Connect

The purpose of the study is to determine the relationship between radiation-induced complications with dosimetric and radiobiological parameters for prostate cancer patients that underwent the conformal radiotherapy treatment. 17 prostate cancer patients that have been treated with conformal radiotherapy were retrospectively analysed. The dosimetric data was retrieved in the form of dose-volume histogram (DVH) from Radiotherapy Treatment Planning System. The DVH was utilised to derived Normal Tissue Complication Probability (NTCP) in radiobiological data. Follow-up data from medical records were used to grade the occurrence of acute gastrointestinal (GI) and genitourinary (GU) complications using Radiation Therapy Oncology Group (RTOG) scoring system. The chi-square test was used to determine the relationship between radiation-induced complication with dosimetric and radiobiological parameters. 8 (47%) and 7 (41%) patients were having acute GI and GU complications respectively. The acute GI complication can be associated with V60{sub rectum}, rectal mean dose and NTCP{sub rectum} with p-value of 0.016, 0.038 and 0.049 respectively. There are no significant relationships of acute GU complication with dosimetric and radiobiological variables. Further study can be done by increase the sample size and follow up duration for deeper understanding of the factors that effecting the GU and GI complication in prostate cancer radiotherapy.

Azuddin, A. Yusof [School of Applied Physics, Faculty of Sciences and Technology, Universiti Kebangsaan Malaysia, 43600 UKM Bangi, Selangor, Malaysia and Faculty of Health Sciences, Universiti Kebangsaan Malaysia, 53000 Kuala Lumpur (Malaysia); Rahman, I. Abdul; Mohamed, F. [School of Applied Physics, Faculty of Sciences and Technology, Universiti Kebangsaan Malaysia, 43600 UKM Bangi, Selangor (Malaysia); Siah, N. J. [Faculty of Health Sciences, Universiti Kebangsaan Malaysia, 53000 Kuala Lumpur (Malaysia); Saadc, M. [Department of Oncology, University Malaya Medical Center, 50603 Kuala Lumpur (Malaysia); Ismail, F. [Department of Oncology and Radiotherapy, Universiti Kebangsaan Malaysia Medical Centre, 56000 Cheras, Kuala Lumpur (Malaysia)

2014-09-03

385

Increased Susceptibility of Radiation-Induced Intestinal Apoptosis in SMP30 KO Mice  

PubMed Central

Recently, senescence marker protein-30 (SMP30) knockout (KO) mice have been reported to be susceptible to apoptosis, however, the role of SMP30 has not been characterized in the small intestine. The aim of the present study is to investigate the role of SMP30 in the process of spontaneous and ?-radiation-induced apoptosis in mouse small intestine. Eight-week-old male wild-type (WT) mice and SMP30 KO mice were examined after exposure to 0, 1, 3, 5, and 9 Gy of ?-radiation. Apoptosis in the crypts of the small intestine increased in the 0 to 5 Gy radiated SMP30 KO and WT mice. Radiation-induced apoptosis and the BAX/Bcl-2 ratio in the SMP30 KO mice were significantly increased in comparison to each identically treated group of WT mice (p < 0.05). The levels of spontaneous apoptosis in both WT and KO mice were similar (p > 0.05), indicating that increased apoptosis of crypt cells of SMP30 KO by irradiation can be associated with SMP30 depletion. These results suggested that SMP30 might be involved in overriding the apoptotic homeostatic mechanism in response to DNA damage. PMID:23708106

Goo, Moon-Jung; Park, Jin-Kyu; Hong, Il-Hwa; Kim, Ah-Young; Lee, Eun-Mi; Lee, Eun-Joo; Hwang, Meeyul; Jeong, Kyu-Shik

2013-01-01

386

A biological approach to the interspecies prediction of radiation-induced mortality risk  

SciTech Connect

Evolutionary explanations for why sexually reproducing organisms grow old suggest that the forces of natural selection affect the ages when diseases occur that are subject to a genetic influence (referred to here as intrinsic diseases). When extended to the population level for a species, this logic leads to the general prediction that age-specific death rates from intrinsic causes should begin to rise as the force of selection wanes once the characteristic age of sexual maturity is attained. Results consistent with these predictions have been found for laboratory mice, beagles, and humans where, after adjusting for differences in life span, it was demonstrated that these species share a common age pattern of mortality for intrinsic causes of death. In quantitative models used to predict radiation-induced mortality, risks are often expressed as multiples of those observed in a control population. A control population, however, is an aging population. As such, mortality risks related to exposure must be interpreted relative to the age-specific risk of death associated with aging. Given the previous success in making interspecies predictions of age-related mortality, the purpose of this study was to determine whether radiation-induced mortality observed in one species could also be predicted quantitatively from a model used to describe the mortality consequences of exposure to radiation in a different species. Mortality data for B6CF{sub 1} mice and beagles exposed to {sup 60}Co {gamma}-rays for the duration of life were used for analysis.

Carnes, B.A.; Grahn, D. [Argonne National Lab., IL (United States). Center for Mechanistic Biology and Biotechnology; Olshansky, S.J. [Univ. of Chicago, IL (United States). Dept. of Medicine

1997-08-01

387

Radiation-induced attenuation self-compensating effect in super-fluorescent fiber source  

NASA Astrophysics Data System (ADS)

The compact super-fluorescent fiber source (SFS) output spectra variations at different pump currents and under different dose of gamma-ray radiation were measured and compared respectively. The radiation-induced attenuation (RIA) self-compensating effect in SFS based on photo-bleaching was found and the general mathematic model of SFS output spectra variations was made. The radiation-induced background attenuation (RIBA) at the pump wavelength was identified to be the main cause of the total output power and spectra variations and the variations can then be compensated by active control of the pump power to enhance the self-compensating effect. With closed-loop feedback control of pump current, double-pass backward (DPB) configuration and spectrum re-shaping technology, an SFS prototype was made and tested. The mean-wavelength stability of about 87.4 ppm and output power instability of less than 5% were achieved under up to 200 krad (Si) gamma-ray irradiation.

Yang, Yuan-Hong; Suo, Xin-Xin; Yang, Wei

2014-09-01

388

Radiation-induced acid ceramidase confers prostate cancer resistance and tumor relapse  

PubMed Central

Escape of prostate cancer (PCa) cells from ionizing radiation–induced (IR-induced) killing leads to disease progression and cancer relapse. The influence of sphingolipids, such as ceramide and its metabolite sphingosine 1-phosphate, on signal transduction pathways under cell stress is important to survival adaptation responses. In this study, we demonstrate that ceramide-deacylating enzyme acid ceramidase (AC) was preferentially upregulated in irradiated PCa cells. Radiation-induced AC gene transactivation by activator protein 1 (AP-1) binding on the proximal promoter was sensitive to inhibition of de novo ceramide biosynthesis, as demonstrated by promoter reporter and ChIP-qPCR analyses. Our data indicate that a protective feedback mechanism mitigates the apoptotic effect of IR-induced ceramide generation. We found that deregulation of c-Jun induced marked radiosensitization in vivo and in vitro, which was rescued by ectopic AC overexpression. AC overexpression in PCa clonogens that survived a fractionated 80-Gy IR course was associated with increased radioresistance and proliferation, suggesting a role for AC in radiotherapy failure and relapse. Immunohistochemical analysis of human PCa tissues revealed higher levels of AC after radiotherapy failure than those in therapy-naive PCa, prostatic intraepithelial neoplasia, or benign tissues. Addition of an AC inhibitor to an animal model of xenograft irradiation produced radiosensitization and prevention of relapse. These data indicate that AC is a potentially tractable target for adjuvant radiotherapy. PMID:24091326

Cheng, Joseph C.; Bai, Aiping; Beckham, Thomas H.; Marrison, S. Tucker; Yount, Caroline L.; Young, Katherine; Lu, Ping; Bartlett, Anne M.; Wu, Bill X.; Keane, Barry J.; Armeson, Kent E.; Marshall, David T.; Keane, Thomas E.; Smith, Michael T.; Jones, E. Ellen; Drake, Richard R.; Bielawska, Alicja; Norris, James S.; Liu, Xiang

2013-01-01

389

Development of Small-Molecule PUMA Inhibitors for Mitigating Radiation-Induced Cell Death  

PubMed Central

PUMA (p53 upregulated modulator of apoptosis) is a Bcl-2 homology 3 (BH3)-only Bcl-2 family member and a key mediator of apoptosis induced by a wide variety of stimuli. PUMA is particularly important in initiating radiation-induced apoptosis and damage in the gastrointestinal and hematopoietic systems. Unlike most BH3-only proteins, PUMA neutralizes all five known antiapoptotic Bcl-2 members through high affinity interactions with its BH3 domain to initiate mitochondria-dependent cell death. Using structural data on the conserved interactions of PUMA with Bcl-2-like proteins, we developed a pharmacophore model that mimics these interactions. In silico screening of the ZINC 8.0 database with this pharmacophore model yielded 142 compounds that could potentially disrupt these interactions. Thirteen structurally diverse compounds with favorable in silico ADME/Toxicity profiles have been retrieved from this set. Extensive testing of these compounds using cell-based and cell-free systems identified lead compounds that confer considerable protection against PUMA-dependent and radiation-induced apoptosis, and inhibit the interaction between PUMA and Bcl-xL. PMID:21320058

Mustata, Gabriela; Li, Mei; Zevola, Nicki; Bakan, Ahmet; Zhang, Lin; Epperly, Michael; Greenberger, Joel S.; Yu, Jian; Bahar, Ivet

2011-01-01

390

Lycopene protects the structure of the small intestine against gamma-radiation-induced oxidative stress.  

PubMed

The small intestine displays numerous morphological and functional alterations after exposure to ionizing radiations. Oxidative stress and changes in monoamines levels may contribute toward some of these alterations. The objective of the current work is to evaluate the efficacy of lycopene on radiation-induced damage in the small intestine. Lycopene (5 mg/kg BW) was given to male albino rats, via gavages for 7 days before whole body exposure to gamma ray (6 Gy). Irradiated animals, sacrificed 7 days after irradiation, showed sloughing villi, ulcers, and ruptured goblet cells, shrinkage of submucosa layers, more fibers and fibroblasts. Histopathological changes were associated with a significant increase in thiobarbituric acid reactive substances (TBARS) and alteration in xanthine oxidoreductase system (XOR). In parallel, significant decreases in reduced glutathione (GSH) content, superoxide dismutase (SOD) and catalase (CAT) activities were recorded. Gamma irradiation has also induced a significant decrease in the level of monoamines: serotonin (5-HT), dopamine (DA), norepinephrine (NE), and epinephrine (EPI) associated with an increase in monoamine-oxidase (MAO) activity. Lycopene pretreatment has significantly improved the oxidant/antioxidant status, which was associated with significant regeneration of the small intestine, and improved monoamines levels. Based on these results, it is concluded that lycopene may protect the small intestine against radiation-induced damage. PMID:20041432

Saada, Helen N; Rezk, Renée G; Eltahawy, Noaman A

2010-06-01

391

Considerations for comparing radiation-induced chromosome aberration data with predictions from biophysical models  

NASA Astrophysics Data System (ADS)

Biophysical models addressing the formation of radiation-induced chromosome aberrations are usually based on the assumption that chromosome aberrations are formed by DNA double strand break (DSB) misrejoining, via either the homologous or the non-homologous repair pathway. However, comparing chromosome aberration data with model predictions is not always straightforward. In this paper we discuss some of the aspects that must be considered to make these comparisons meaningful. Firstly, biophysical models are usually applied to DSB rejoining and misrejoining in the G0/G1 phase of the cell cycle, while most chromosome aberration data reported in the literature are analyzed in metaphase. Since cells must progress through the cell cycle check points in order to reach mitosis, model predictions that differ from the metaphase chromosome analysis may actually agree with the aberration data in chromosomes collected in interphase. Secondly, high- LET radiation generally produces more complex aberrations involving exchanges between three or more DSB. While some models have successfully provided quantitative predictions of high-LET radiation induced complex aberrations in human lymphocytes, applying such models to other cell types requires special considerations due to the lack of geometric symmetry of the nucleus. Chromosome aberration data for non-spherical human fibroblast cells bombarded from various directions by high-LET charged particles will be presented, and their implication on physical modeling will be discussed.

Wu, H.; Furusawa, Y.; George, K.; Kawata, T.; Cucinotta, F.

392

Mitigating the risk of radiation-induced cancers: limitations and paradigms in drug development.  

PubMed

The United States radiation medical countermeasures (MCM) programme for radiological and nuclear incidents has been focusing on developing mitigators for the acute radiation syndrome (ARS) and delayed effects of acute radiation exposure (DEARE), and biodosimetry technologies to provide radiation dose assessments for guiding treatment. Because a nuclear accident or terrorist incident could potentially expose a large number of people to low to moderate doses of ionising radiation, and thus increase their excess lifetime cancer risk, there is an interest in developing mitigators for this purpose. This article discusses the current status, issues, and challenges regarding development of mitigators against radiation-induced cancers. The challenges of developing mitigators for ARS include: the long latency between exposure and cancer manifestation, limitations of animal models, potential side effects of the mitigator itself, potential need for long-term use, the complexity of human trials to demonstrate effectiveness, and statistical power constraints for measuring health risks (and reduction of health risks after mitigation) following relatively low radiation doses (<0.75 Gy). Nevertheless, progress in the understanding of the molecular mechanisms resulting in radiation injury, along with parallel progress in dose assessment technologies, make this an opportune, if not critical, time to invest in research strategies that result in the development of agents to lower the risk of radiation-induced cancers for populations that survive a significant radiation exposure incident. PMID:24727460

Yoo, Stephen S; Jorgensen, Timothy J; Kennedy, Ann R; Boice, John D; Shapiro, Alla; Hu, Tom C-C; Moyer, Brian R; Grace, Marcy B; Kelloff, Gary J; Fenech, Michael; Prasanna, Pataje G S; Coleman, C Norman

2014-06-01

393

PHD Inhibition Mitigates and Protects Against Radiation-Induced Gastrointestinal Toxicity via HIF2  

PubMed Central

Radiation-induced gastrointestinal (GI) toxicity can be a major source of morbidity and mortality after radiation exposure. There is an unmet need for effective preventative or mitigative treatments against the potentially fatal diarrhea and water loss induced by radiation damage to the GI tract. We report that prolyl hydroxylase inhibition by genetic knockout or pharmacologic inhibition of all PHD isoforms by the small molecule dimethyloxyallylglycine (DMOG) increases HIF expression, improves epithelial integrity, reduces apoptosis, and increases intestinal angiogenesis, all of which are essential for radioprotection. HIF2, but not HIF1, is both necessary and sufficient to prevent radiation-induced GI toxicity and death. Increased VEGF expression contributes to the protective effects of HIF2, since inhibition of VEGF function reversed the radioprotection and radiomitigation afforded by DMOG. Additionally, mortality is reduced from abdominal or total body irradiation even when DMOG is given 24 hours after exposure. Thus, prolyl hydroxylase inhibition represents a new treatment strategy to protect against and mitigate GI toxicity from both therapeutic radiation and potentially lethal radiation exposures. PMID:24828078

Taniguchi, Cullen M.; Miao, Yu Rebecca; Diep, Anh N.; Wu, Colleen; Rankin, Erinn B.; Atwood, Todd F.; Xing, Lei; Giaccia, Amato J.

2014-01-01

394

Does altered fractionation influence the risk of radiation-induced optic neuropathy?  

SciTech Connect

Purpose: To analyze the parameters that influence the risk of radiation-induced optic neuropathy (RION) after radiotherapy for head-and-neck tumors. Methods and Materials: Between 1964 and 2000, 273 patients with tumors of the nasopharynx, paranasal sinuses, nasal cavity, and hard palate adenoid cystic carcinomas were treated with curative intent and had radiation fields that included the optic nerves and/or chiasm. Patients were followed for at least 1 year after radiotherapy. Results: Radiation-induced optic neuropathy developed in 32 eyes of 24 patients (9%). The 5-year rates of freedom from RION according to the total dose and once- vs. twice-daily fractionation were as follows: {<=}63 Gy once daily, 95%; {<=}63 Gy twice daily, 98%; >63 Gy once daily, 78%; and >63 Gy twice daily, 91%. Multivariate analysis revealed that the total dose affected the risk of RION (p = 0.0047), with patient age (p = 0.0909), once-daily vs. twice-daily fractionation (p = 0.0684), and overall treatment time (p = 0.0972) were marginally significant. The use of adjuvant chemotherapy did not significantly influence the likelihood of developing RION. Conclusion: The likelihood of developing RION is primarily influenced by the total dose. Hyperfractionation may reduce the risk of experiencing this complication.

Bhandare, Niranjan [Department of Radiation Oncology, University of Florida College of Medicine, Gainesville, FL (United States); Monroe, Alan T. [Department of Radiation Oncology, University of Florida College of Medicine, Gainesville, FL (United States); Morris, Christopher G. [Department of Radiation Oncology, University of Florida College of Medicine, Gainesville, FL (United States); Bhatti, M. Tariq [Department of Ophthalmology, Neurology, and Neurosurgery, University of Florida College of Medicine, Gainesville, FL (United States); Mendenhall, William M. [Department of Radiation Oncology, University of Florida College of Medicine, Gainesville, FL (United States)]. E-mail: mendewil@shands.ufl.edu

2005-07-15

395

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

PubMed

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

Toklu, Hale Z; Sehirli, Ozer; Ozyurt, Hazan; Mayada?li, A Alpaslan; Ek?io?lu-Demiralp, Emel; Cetinel, Sule; Sahin, Hülya; Ye?en, Berrak C; Ulusoylu Dumlu, Melek; Gökmen, Vural; Sener, Göksel

2009-07-01

396

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

SciTech Connect

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

Persinger, S.M.; Town, C.D. (Case Western Reserve Univ., Cleveland, OH (USA))

1989-04-01

397

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

PubMed

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

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

2008-12-15

398

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

NASA Astrophysics Data System (ADS)

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

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

2009-12-01

399

Radiation-induced cardiovascular diseases: Is the epidemiologic evidence compatible with the radiobiologic data?  

SciTech Connect

The Life Span Study of Japanese atomic bomb survivors demonstrates that radiation exposure significantly increased the risk of developing ischemic heart disease, in particular myocardial infarction. Similarly, epidemiologic investigations in very large populations of patients who had received postoperative radiotherapy for breast cancer or for peptic ulcer demonstrate that radiation exposure of the heart with an average equivalent single dose of approximately 2 Gy significantly increased the risk of developing ischemic heart disease more than 10 years after irradiation. These epidemiologic findings are compatible with radiobiologic data on the pathogenesis of radiation-induced heart disease in experimental animals. The critical target structure appears to be the endothelial lining of blood vessels, in particular arteries, leading to early functional alterations such as pro-inflammatory responses and other changes, which are slowly progressive. Research should concentrate on the interaction of these radiation-induced endothelial changes with the early stages of age-related atherosclerosis to develop criteria for optimizing treatment plans in radiotherapy and also potential interventional strategies.

Schultz-Hector, Susanne [Helmholtz-Gemeinschaft, Berlin (Germany)]. E-mail: susanne.schultz-hector@helmholtz.de; Trott, Klaus-Ruediger Prof. [Gray Cancer Institute, Northwood (United Kingdom)

2007-01-01

400

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

NASA Astrophysics Data System (ADS)

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

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

2001-01-01

401

Protective effect of triphala on radiation induced acute intestinal mucosal damage in Sprague Dawley rats.  

PubMed

Aim of the study was to determine protective effect of triphala on radiation-induced rectal mucosal damage. Male Sprague Dawley rats (30) were divided into 5 groups. Rats in group A were sham irradiated and rats in group B underwent only irradiation. Rats in group C were administered triphala 1 g/kg/day orally for 5 consecutive days before irradiation. Rats in group D and E were administered triphala 1 and 1.5 g/kg/day orally for 10 consecutive days, respectively. Rectal mucosal damage was induced by a single fraction of 12.5Gy gamma irradiation (Ir-192) on 5th day. All the rats were autopsied on 11th day and histological changes in surface epithelium, glands, and lamina propria were assessed. Proctitis showed significant improvement in surface epithelium (P < 0.024), glands (P < 0.000) and lamina propria (P < 0.002) in group E compared to group B. Rats in group E showed significantly less change in glands (P < 0.000) compared to rats in group D, All histological variables (surface epithelium, P < 0.001; glands, P < 0.000; lamina propria, P < 0.003) compared to rats in group C. In a Tukey-b test, group E had a significantly recovered grade for glands (P < 0.000) compared to groups B, C and D. Results of the present study showed that high-dose triphala improved radiation-induced damage of glands. PMID:22439434

Yoon, Won Sup; Kim, Chul Yong; Yang, Dae Sik; Park, Young Je; Park, Won; Ahn, Yong Chan; Kim, Seok-Hyung; Kwon, Ghee Young

2012-03-01

402

Protection by polaprezinc against radiation-induced apoptosis in rat jejunal crypt cells.  

PubMed

Polaprezinc, an anti-ulcer drug, is a chelate compound consisting of zinc and L-carnosine. Polaprezinc has been shown to prevent gastric mucosal injury. The anti ulcer effects of polaprezinc have been ascribed to its antioxidative property. The effect of polaprezinc on ionizing radiation-induced apoptosis was studied in the jejunal epithelial crypt cells of rats. Seven-to eight week-old Wistar rats, which were treated with 100 mg/kg of polaprezinc orally 1h before irradiation or 2% carboxymethyl cellulose sodium in controls, were exposed to whole body X-ray irradiation at 2 Gy. The number of apoptotic cells per jejunum crypt was counted in haematoxylin and eosin stained sections at 0-6 h after irradiation. TUNEL positive cells and immunopositive cells for active caspase-3 per crypt were also counted. Accumulation of p53, p21(WAF1/CIP1) and Bax expression in the jejunum after irradiation were examined by Western blot analyses. Polaprezinc treatment given prior to radiation resulted in a significant reduction in numbers of apoptotic cells, TUNEL positive cells and active caspase-3 immunopositive cells in jejunal crypt cells. Polaprezinc treatment resulted in decreases of p53 accumulation, p21(WAF1/CIP1) and Bax expression after irradiation. Polaprezinc has a protective effect against ionizing radiation induced apoptosis in rat jejunal crypt cells. PMID:18413982

Matsuu-Matsuyama, Mutsumi; Shichijo, Kazuko; Okaichi, Kumio; Nakayama, Toshiyuki; Nakashima, Masahiro; Uemura, Takashi; Niino, Daisuke; Sekine, Ichiro

2008-07-01

403

Radiation-induced crosslinking and post-processing of poly( L-lactic acid) composite  

NASA Astrophysics Data System (ADS)

Poly( L-lactic acid), PLLA, was irradiated using electron beams (EBs) in the presence of triallyl isocyanurate (TAIC) at 5% concentration as crosslinking agent. The crosslinked PLLA obtained has heat resistance, as demonstrated by retention of its original shape at glass transition temperature or even higher than 200 °C. As an application of this fact, crosslinked PLLA is applied in spectacle lens to prevent shape deformation of eyeglass frames in displaying and transporting. However, in this application to lens, it is not enough to improve the thermal deformation of PLLA under stress at 70 °C. Radiation-induced crosslinking of a PLLA/silicon dioxide (SiO 2) composite with TAIC and post-processing of the crosslinked PLLA composite by heating were further investigated from the viewpoint of thermal deformation. The PLLA materials have several advantages such as high heat resistance and transparency. It is therefore proved that the combination of radiation-induced crosslinking, composition of SiO 2 and post-heating is beneficial for expanding the applications of PLLA.

Nagasawa, Naotsugu; Kasai, Noboru; Yagi, Toshiaki; Yoshii, Fumio; Tamada, Masao

2011-02-01

404

The nucleus is the target for radiation-induced chromosomal instability  

NASA Technical Reports Server (NTRS)

We have previously described chromosomal instability in cells of a human-hamster hybrid cell line after exposure to X rays. Chromosomal instability in these cells is characterized by the appearance of novel chromosomal rearrangements multiple generations after exposure to ionizing radiation. To identify the cellular target(s) for radiation-induced chromosomal instability, cells were treated with 125I-labeled compounds and frozen. Radioactive decays from 125I cause damage to the cell primarily at the site of their decay, and freezing the cells allows damage to accumulate in the absence of other cellular processes. We found that the decay of 125I-iododeoxyuridine, which is incorporated into the DNA, caused chromosomal instability. While cell killing and first-division chromosomal rearrangements increased with increasing numbers of 125I decays, the frequency of chromosomal instability was independent of dose. Chromosomal instability could also be induced from incorporation of 125I-iododeoxyuridine without freezing the cells for accumulation of decays. This indicates that DNA double-strand breaks in frozen cells resulting from 125I decays failed to lead to instability. Incorporation of an 125I-labeled protein (125I-succinyl-concanavalin A), which was internalized into the cell and/or bound to the plasma membrane, neither caused chromosomal instability nor potentiated chromosomal instability induced by 125I-iododeoxyuridine. These results show that the target for radiation-induced chromosomal instability in these cells is the nucleus.

Kaplan, M. I.; Morgan, W. F.

1998-01-01

405

Radiation-induced processes at oxide surfaces and interfaces relevant to spent nuclear fuel storage  

SciTech Connect

Gas generation, oxidation, corrosion, and other important phenomena accompanying the long-term storage of spent nuclear fuel (SNF) are highly affected by radiation-induced processes at oxide surfaces and interfaces. Oxides covering fuel rods and other surfaces, as well as oxide particles dispersed in the aqueous phase, can promote water radiolysis and decomposition. Surface-enhanced water radiolysis may accelerate oxidation, corrosion, and hydriding of Zircaloy, uranium, and other materials and may affect the amount of H{sub 2} and O{sub 2} produced during SNF storage. Mechanisms of surface-enhanced radiolysis are not well understood. Some proposed mechanisms are based on the transfer of energy initially deposited in the bulk of the oxide phase to the interface. This process depends on the oxide electronic structure and on the energetics and geometric structures of the adsorbed molecules. Typically, mobile electrons, holes, and excitons contribute to the enhancement. Their effective range is directly related to carrier mean free paths and excited state lifetimes. These parameters can be studied with a technique known as laser-stimulated luminescence (LSL). The authors present data on the gamma radiation-induced degradation of water at oxide particle/water interfaces and on time-resolved LSL measurements of ZrO{sub 2} recombination luminescence.

Petrik, N.G.; Alexandrov, A.B.; Orlando, T.M.; Vall, A.I.

1999-07-01

406

Antihistamines block radiation-induced increased intestinal blood flow in canines  

SciTech Connect

Radiation-induced systemic hypotension is accompanied by increased intestinal blood flow (IBF) and an increased hematocrit (HCT) in dogs. Histamine infusion leads to increased IBF and intestinal edema with consequent secretion of fluid into the intestinal lumen. This study was performed to determine whether these effects could be diminished by prior administration of H/sub 1/ and H/sub 2/ histamine blockers. Dogs were given an iv infusion of mepyramine (0.5 mg/min) and cimetidine (0.25 mg/min) for 1 hr before and for 1 hr after radiation (H sub 1 and H sub 2 blockers, respectively). Mean systemic arterial blood pressure (MBP), IBF, and HCT were monitored for 2 hr. Systematic plasma histamine levels were determined simultaneously. Data obtained indicated that the H sub 1 and H sub 2 blockers, given simultaneously, were successful in blocking the increased IBF and the increased HCT seen after 100 Gy, whole-body, gamma radiation. However, the postradiation hypotension was only somewhat affected, with the MBP falling to a level 28% below the preradiation level. Plasma histamine levels reached a sharp peak, as much as 20% above baseline, at 4 min postradiation. These findings implicate histamine in the radiation-induced increase in IBF and HCT but not for the gradual decrease in postradiation blood pressure. (Author)

Cockerham, L.G.; Doyle, T.F.; Donlon, M.A.; Gossett-Hagerman, C.J.

1985-01-01

407

Antihistamines block radiation-induced increased intestinal blood flow in canines  

SciTech Connect

Radiation-induced systemic hypotension is accompanied by increased intestinal blood flow (IBF) and an increased hematocrit (HCT) in dogs. Histamine infusion leads to increased IBF and intestinal edema with consequent secretion of fluid into the intestinal lumen. This study was performed to determine whether these effects could be diminished by prior administration of H1 and H2 histamine blockers. Dogs were given an iv infusion of mepyramine (0.5 mg/min) and cimetidine (0.25 mg/min) for 1 hr before and for 1 hr after radiation (H1 and H2 blockers, respectively). Mean systemic arterial blood pressure (MBP), IBF, and HCT were monitored for 2 hr. Systemic plasma histamine levels were determined simultaneously. Data obtained indicated that the H1 and H2 blockers, given simultaneously, were successful in blocking the increased IBF and the increased HCT seen after 100 Gy, whole-body, gamma radiation. However, the postradiation hypotension was only somewhat affected, with the MBP falling to a level 28% below the preradiation level. Plasma histamine levels reached a sharp peak, as much as 20% above baseline, at 4 min postradiation. These findings implicate histamine in the radiation-induced increase in IBF and HCT but not for the gradual decrease in postradiation blood pressure.

Cockerham, L.G.; Doyle, T.F.; Donlon, M.A.; Gossett-Hagerman, C.J.

1985-06-01

408

Mucoadhesive propolis gel for prevention of radiation-induced oral mucositis.  

PubMed

The objective of this phase II study was to determine the effectiveness of a mucoadhesive propolis gel in the prevention of radiation-induced oral mucositis. Twenty-four patients who were selected to undergo radiation therapy for oral cancer were included in this open-label trial. They were advised to use a mucoadhesive gel containing propolis 5,0% w/v three times a day starting one day before the course of radiation therapy and concluding after 2 weeks of radiation therapy. A weekly follow-up for evaluation of food intake, pain and grading of mucositis was performed. In order to confirm the absence of Candida-related mucositis in patients who developed mucositis, it was performed exfoliative cytology of buccal mucosa, palate and tongue and the material for Candifast(®) Candida species identification. At the end of the study was made the compliance of patients, quality, appreciation and acceptance of product evaluation. Twenty patients did not develop mucositis, two patients developed grade 1 mucositis and two patients developed grade 2 mucositis. None of the patients discontinued food intake and no pain was observed during the study. Candidosis was not detected in any patient. Mucoadhesive propolis gel could be considered as a potential topical medication for preventing radiation-induced oral mucositis. However, comparative phase III study with larger number of patients should be done for confirmation of the efficacy of the product. PMID:24502424

Noronha, Vladimir R A S; Araujo, Gustavo S; Gomes, Rafael T; Iwanaga, Samara H; Barbosa, Maralice C; Abdo, Evandro N; Ferreira e Ferreira, Efigenia; Viana Campos, Ana C; Souza, Alexandre A; Abreu, Sheila R L; Santos, Vagner R

2014-01-01

409

Radiation-induced malignant fibrous histiocytoma of the occipital: a case report  

PubMed Central

Malignant fibrous histiocytoma (MFH) is a rare neoplasm exhibiting a propensity for aggressive clinical behavior. Effective treatment modality is surgical resection with wide margins, but its rate of recurrence and metastasis is still high. Early detection and complete excision of the tumor is necessary. A MFH of the occipital developed in a 51-year-old woman eight years after surgery and radiation for medulloblastoma of the cerebellar vermis. The secondary neoplasm arose at the site of tumor resection within the irradiated field, and was resected. The development of sarcomas is a recognized complication of radiation therapy. The final diagnosis after the operation was MFH. Radiation-induced sarcoma (RIS) is well known, but radiation-induced MFH is relatively rare in the head and neck region, especially in the occipital. The imaging findings are not diagnosis specific, but strict follow-up within the radiation field by computerized tomography (CT) and magnetic resonance imaging (MRI) and appreciation of the expected latency period may help in providing the diagnosis of RIS. PMID:24742094

2014-01-01

410

Prevention effects of Schisandra polysaccharide on radiation-induced immune system dysfunction.  

PubMed

In this study, we investigate the efficacy of SP (Schisandra polysaccharide) in prevention of radiation-induced immune dysfunction and discussed the underlying mechanisms with a Bal/bc mouse model. The data demonstrated that SP could reverse the decreases in the number of white blood cells and lymphocytes in peripheral blood. In addition, the immunoglobulin G (IgG) and complement C3 in blood serum were all decreased after radiation and SP could restore this radiation disorder. Furthermore, SP could reverse the deregulation of CD3(+)CD4(+) and CD3(+)CD8(+) T cell subsets in peripheral blood and thymus of mice after radiotherapy. We also performed terminal dexynucleotidyl transferase (TdT)-mediated dUTP nick end labeling (TUNEL) and Immunohistochemistry (IHC) to investigate the apoptosis and underlying mechanisms of SP in thymus. Data showed that radiation-induced apoptosis of thymocytes could be reversed by SP through inducing upregulation of Bcl-2 expression and downregulation of Fas and Bax levels. Furthermore, SP has no any side-effects on immunity of normal mice. In conclusion, our results indicated that SP could effectively prevent immune injury during radiotherapy by protecting the immune system. This valuable information should be of assistance in choosing a rational design for therapeutic interventions of prevention immune system damage in the radiation treatment. PMID:25709011

Zhao, Lian-Mei; Jia, Yun-Long; Ma, Ming; Duan, Yu-Qing; Liu, Li-Hua

2015-05-01

411

Neuroanatomical target theory as a predictive model for radiation-induced cognitive decline  

PubMed Central

Objective: In a retrospective review to assess neuroanatomical targets of radiation-induced cognitive decline, dose volume histogram (DVH) analyses of specific brain regions of interest (ROI) are correlated to neurocognitive performance in 57 primary brain tumor survivors. Methods: Neurocognitive assessment at baseline included Trail Making Tests A/B, a modified Rey-Osterreith Complex Figure, California or Hopkins Verbal Learning Test, Digit Span, and Controlled Oral Word Association. DVH analysis was performed for multiple neuroanatomical targets considered to be involved in cognition. The %v10 (percent of ROI receiving 10 Gy), %v40, and %v60 were calculated for each ROI. Factor analysis was used to estimate global cognition based on a summary of performance on individual cognitive tests. Stepwise regression was used to determine which dose volume predicted performance on global factors and individual neurocognitive tests for each ROI. Results: Regions that predicted global cognitive outcomes at doses <60 Gy included the corpus callosum, left frontal white matter, right temporal lobe, bilateral hippocampi, subventricular zone, and cerebellum. Regions of adult neurogenesis primarily predicted cognition at %v40 except for the right hippocampus which predicted at %v10. Regions that did not predict global cognitive outcomes at any dose include total brain volume, frontal pole, anterior cingulate, right frontal white matter, and the right precentral gyrus. Conclusions: Modeling of radiation-induced cognitive decline using neuroanatomical target theory appears to be feasible. A prospective trial is necessary to validate these data. PMID:23390169

Leyrer, C. Marc; Greene-Schloesser, Dana M.; Shing, Elaine; Kearns, William T.; Hinson, William H.; Tatter, Stephen B.; Ip, Edward H.; Rapp, Stephen R.; Robbins, Mike E.; Shaw, Edward G.; Chan, Michael D.

2013-01-01

412

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

SciTech Connect

Purpose: Hepatocellular carcinoma (HCC) is one of the most common and lethal human malignancies. Lack of efficient therapy for advanced HCC is a pressing problem worldwide. This study aimed to determine the efficacy and mechanism of combined sorafenib and radiation therapy treatment for HCC. Methods and Materials: HCC cell lines (PLC5, Huh-7, Sk-Hep1, and Hep3B) were treated with sorafenib, radiation, or both, and apoptosis and signal transduction were analyzed. Results: All 4 HCC cell lines showed resistance to radiation-induced apoptosis; however, this resistance could be reversed in the presence of sorafenib. Inhibition of phospho-STAT3 was found in cells treated with sorafenib or sorafenib plus radiation and subsequently reduced the expression levels of STAT3-related proteins, Mcl-1, cyclin D1, and survivin. Silencing STAT3 by RNA interference overcame apoptotic resistance to radiation in HCC cells, and the ectopic expression of STAT3 in HCC cells abolished the radiosensitizing effect of sorafenib. Moreover, sorafenib plus radiation significantly suppressed PLC5 xenograft tumor growth. Conclusions: These results indicate that sorafenib sensitizes resistant HCC cells to radiation-induced apoptosis via downregulating phosphorylation of STAT3 in vitro and in vivo.

Huang, Chao-Yuan [Department of Oncology, National Taiwan University Hospital and National Taiwan University College of Medicine, Taipei, Taiwan (China) [Department of Oncology, National Taiwan University Hospital and National Taiwan University College of Medicine, Taipei, Taiwan (China); Department of Radiological Technology, Yuanpei University, Hsinchu, Taiwan (China); Lin, Chen-Si [School of Veterinary Medicine, National Taiwan University Hospital, Taipei, Taiwan (China)] [School of Veterinary Medicine, National Taiwan University Hospital, Taipei, Taiwan (China); Tai, Wei-Tien; Hsieh, Chi-Ying [Department of Medical Research, National Taiwan University Hospital, Taipei, Taiwan (China) [Department of Medical Research, National Taiwan University Hospital, Taipei, Taiwan (China); National Center of Excellence for Clinical Trial and Research, National Taiwan University Hospital, Taipei, Taiwan (China); Shiau, Chung-Wai [Institute of Biopharmaceutical Sciences, National Yang-Ming University, Taipei, Taiwan (China)] [Institute of Biopharmaceutical Sciences, National Yang-Ming University, Taipei, Taiwan (China); Cheng, Ann-Lii [Department of Oncology, National Taiwan University Hospital and National Taiwan University College of Medicine, Taipei, Taiwan (China) [Department of Oncology, National Taiwan University Hospital and National Taiwan University College of Medicine, Taipei, Taiwan (China); National Center of Excellence for Clinical Trial and Research, National Taiwan University Hospital, Taipei, Taiwan (China); Chen, Kuen-Feng, E-mail: kfchen1970@ntu.edu.tw [Department of Medical Research, National Taiwan University Hospital, Taipei, Taiwan (China) [Department of Medical Research, National Taiwan University Hospital, Taipei, Taiwan (China); National Center of Excellence for Clinical Trial and Research, National Taiwan University Hospital, Taipei, Taiwan (China)

2013-07-01

413

Comparison of simulated and experimental results for distributed radiation-induced absorption measurement using OFDR reflectometry  

NASA Astrophysics Data System (ADS)

In this paper we present results of computer simulation of the Optical Frequency Domain Reflectometry system used for measuring distributed radiation-induced absorption. We simulated conditions of an experiment in which a highly radiation sensitive optical fibre doped with aluminium was exposed to gamma-radiation. The total exposed dose was about 50 kGy. We measured two backscattering profiles of the fibre network before and right after irradiation to estimate the induced change of the trace slope which in case of optical fibre dosimetry is used for total dose estimation. Then we simulated this experiment using a MATLAB model imitating an optical fibre backscattering profile. The simulation was based on the operational principles of the OFDR system and imitated its measurement algorithm. As a result of simulation we obtained two backscattering traces which were in good conformity with those measured in the real-life experiment. To our knowledge, this is the first time that distributed measurement of radiation-induced absorption using optical frequency domain reflectometry has been simulated.

Faustov, A. V.; Gusarov, Andrei; Liokumovich, L. B.; Fotiadi, A. A.; Wuilpart, M.; Mégret, P.

2013-05-01

414

Brachial plexus palsy after a left-side modified radical mastectomy with immediate latissimusdorsi flap reconstruction: report of a case  

PubMed Central

Brachial plexus injury is a rare complication during operation and anesthesia; it can occur as a result of various mechanisms such as inappropriate positioning, over-abduction and stretching the upper limbs. Brachial plexus injury can cause the poor function of the upper limb before recovery, and sometimes serious injury is unable to completely recovered the function permanently. Here, we report a female breast cancer patient who sustained a left brachial plexus palsy after modified radical mastectomy with immediate breast reconstruction with latissimusdorsi flap (LDF). The patient had fully recovered with normal function of her left upper limb six months postoperation after conservative treatment. PMID:24127915

2013-01-01

415

Sialylation of Integrin beta1 is Involved in Radiation-Induced Adhesion and Migration in Human Colon Cancer Cells  

SciTech Connect

Purpose: Previously, we reported that radiation-induced ST6 Gal I gene expression was responsible for an increase of integrin beta1 sialylation. In this study, we have further investigated the function of radiation-mediated integrin beta1 sialylation in colon cancer cells. Methods and Materials: We performed Western blotting and lectin affinity assay to analyze the expression and level of sialylated integrin beta1. After exposure to ionizing radiation (IR), adhesion and migration of cells were measured by in vitro adhesion and migration assay. Results: IR increased sialylation of integrin beta1 responsible for its increased protein stability and adhesion and migration of colon cancer cells. However, for cells with an N-glycosylation site mutant of integrin beta1 located on the I-like domain (Mu3), these effects were dramatically inhibited. In addition, integrin beta1-mediated radioresistance was not observed in cells containing this mutant. When sialylation of integrin beta1 was targeted with a sulfonamide chalcone compound, inhibition of radiation-induced sialylation of integrin beta1 and inhibition of radiation-induced adhesion and migration occurred. Conclusion: The increase of integrin beta1 sialylation by ST6 Gal I is critically involved in radiation-mediated adhesion and migration of colon cancer cells. From these findings, integrin beta1 sialylation may be a novel target for overcoming radiation-induced survival, especially radiation-induced adhesion and migration.

Lee, Minyoung; Lee, Hae-June [Division of Radiation Effects, Korea Institute of Radiological and Medical Sciences, Seoul (Korea, Republic of); Seo, Woo Duck [Department of Functional Corp, NICS, RDA, Miryang (Korea, Republic of); Park, Ki Hun [Division of Applied Life Science (BK21 program), EB-NCRC, Gyeongsang National University, Jinju (Korea, Republic of); Lee, Yun-Sil, E-mail: yslee@kcch.re.k [Division of Radiation Effects, Korea Institute of Radiological and Medical Sciences, Seoul (Korea, Republic of)

2010-04-15

416

Implication of prostaglandins and histamine h1 and h2 receptors in radiation-induced temperature responses of rats  

SciTech Connect

Exposure of rats to 1-15 Gy cobalt 60 gamma radiation induced hyperthermia, whereas 20-200 Gy induced hypothermia. Exposure either to the head or to the whole body to 10 Gy induced hyperthermia, while body-only exposure produced hypothermia. This observation indicates that radiation-induced fever is a result of a direct effect on the brain. The hyperthermia due to 10 Gy was significantly attenuated by the pre- or post-treatment with a cyclooxgenase inhibitor, indomethacin. Hyperthermia was also altered by the central administration of a mu receptor antagonist naloxone but only at low doses of radiation. These findings suggest that radiation-induced hyperthermia may be mediated through the synthesis and release of prostaglandins in the brain and to a lesser extent to the release of endogenous opioid peptides. The release of histamine acting on H(1) and H(2) receptors may be involved in radiation-induced hypothermia since both the H(1) receptor antagonist, mepyramine, and H(2) receptor antagonist, cimetidine, antagonized the hypothermia. The results of these studies suggested that the release of neurohumoral substances induced by exposure to ionizing radiation is dose dependent and has different consequences on physiological processes such as the regulation of body temperature. Furthermore, the antagonism of radiation-induced hyperthermia by indomethacin may have potential therapeutic implications in the treatment of fever resulting from accidental irradiations.

Kandasamy, S.B.; Hunt, W.A.; Mickley, G.A .

1988-01-01

417

Inactivation of NADPH Oxidases NOX4 and NOX5 Protects Human Primary Fibroblasts from Ionizing Radiation-Induced DNA Damage.  

PubMed

Human exposure to ionizing radiation from medical procedures has increased sharply in the last three decades. Recent epidemiological studies suggest a direct relationship between exposure to ionizing radiation and health problems, including cancer incidence. Therefore, minimizing the impact of radiation exposure in patients has become a priority in the development of future clinical practices. Crucial players in radiation-induced DNA damage include reactive oxygen species (ROS), but the sources of these have remained elusive. To the best of our knowledge, we show here for the first time that two members of the ROS-generating NADPH oxidase family (NOXs), NOX4 and NOX5, are involved in radiation-induced DNA damage. Depleting these two NOXs in human primary fibroblasts resulted in reduced levels of DNA damage as measured by levels of radiation-induced foci, a marker of DNA double-strand breaks (DSBs) and the comet assay coupled with increased cell survival. NOX involvement was substantiated with fulvene-5, a NOXs-specific inhibitor. Moreover, fulvene-5 mitigated radiation-induced DNA damage in human peripheral blood mononuclear cells ex vivo. Our results provide evidence that the inactivation of NOXs protects cells from radiation-induced DNA damage and cell death. These findings suggest that NOXs inhibition may be considered as a future pharmacological target to help minimize the negative effects of radiation exposure for millions of patients each year. PMID:25706776

Weyemi, Urbain; Redon, Christophe E; Aziz, Towqir; Choudhuri, Rohini; Maeda, Daisuke; Parekh, Palak R; Bonner, Michael Y; Arbiser, Jack L; Bonner, William M

2015-03-01

418

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

PubMed Central

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

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

2012-01-01

419

Radiation-induced inflammatory markers of brain injury are modulated by PPARdelta activation in vitro and in vivo  

NASA Astrophysics Data System (ADS)

As a result of improvements in cancer therapy and health care, the population of long-term cancer survivors is growing. For these approximately 12 million long-term cancer survivors, brain metastases are a significant risk. Fractionated partial or whole-brain irradiation (fWBI) is often required to treat both primary and metastatic brain cancer. Radiation-induced normal tissue injury, including progressive cognitive impairment, however, can significantly affect the well-being of the approximately 200,000 patients who receive these treatments each year. Recent reports indicate that radiation-induced brain injury is associated with chronic inflammatory and oxidative stress responses, as well as increased microglial activation in the brain. Anti-inflammatory drugs may, therefore, be a beneficial therapy to mitigate radiation-induced brain injury. We hypothesized that activation of peroxisomal proliferator activated receptor delta (PPAR?) would prevent or ameliorate radiation-induced brain injury, including cognitive impairment, in part, by alleviating inflammatory responses in microglia. For our in vitro studies, we hypothesized that PPAR? activation would prevent the radiation-induced inflammatory response in microglia following irradiation. Incubating BV-2 murine microglial cells with the (PPAR)? agonist, L-165041, prevented the radiation-induced increase in: i) intracellular ROS generation, ii) Cox-2 and MCP-1 expression, and iii) IL-1? and TNF-? message levels. This occured, in part, through PPAR?-mediated modulation of stress activated kinases and proinflammatory transcription factors. PPAR? inhibited NF-?B via transrepression by physically interacting with the p65 subunit, and prevented activation of the PKC?/MEK1/2/ERK1/2/AP-1 pathway by inhibiting the radiation-induced increase in intracellular ROS generation. These data support the hypothesis that PPAR? activation can modulate the radiation-induced oxidative stress and inflammatory responses in microglia in vitro. To extend our in vitro findings in vivo, we investigated whether administration of the peroxisomal proliferator-activated receptor (PPAR)ä agonist, GW0742, prevented radiation-induced brain injury in C57Bl/6 WT mice. Our data demonstrate that GW0742 prevented the radiation-induced increase in the number of activated microglia (CD68+ cells) in wild-type (WT) mice 1 week following 10 Gy WBI. Furthermore, GW0742 inhibited the WBI-induced increase in IL-1? message levels and ERK phosphorylation observed 3 h post-irradiation. In contrast, GW0742 administration failed to modulate the radiation-induced decrease in hippocampal neurogenesis (NeuN+/BrdU+ cells) determined 2 months after irradiation, or mitigate hippocampal-dependent spatial memory impairment observed 3 months post-irradiation using the Barnes Maze task. We used PPAR? knockout (KO) mice to examine if the effects of GW0742 are PPAR?-dependent. Unexpectedly, PPAR? KO mice exhibited a differential response following WBI compared to WT mice; therefore, we were unable to make mechanistic conclusions about GW0742. KO mice do not exhibit a WBI-induced increase in activated microglia; however, they appeared to display a pronounced astrocytic response. In particular, PPAR? KO but not WT mice displayed increased GFAP message levels 2 months after WBI. Additionally, the number of GFAP+ cells was reduced significantly in the WT mice 2 months after WBI, but it was not in the PPAR? KO mice. These results demonstrate that: i) GW0742 prevents the radiation-induced increase in microglial activation and inflammatory markers, and ii) WT and PPAR? KO mice have a differential response to WBI.

Schnegg, Caroline Isabel

420

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

PubMed

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

Anbumani, S; Mohankumar, Mary N

2015-03-01

421

The Development of Countermeasures for Space Radiation Induced Adverse Health Effects  

NASA Astrophysics Data System (ADS)

The Development of Countermeasures for Space Radiation Induced Adverse Health Effects Ann R. Kennedy Department of Radiation Oncology, University of Pennsylvania School of Medicine, 195 John Morgan Building, 3620 Hamilton Walk, Philadelphia, PA, United States 19104-6072 The development of countermeasures for radiation induced adverse health effects is a lengthy process, particularly when the countermeasure/drug has not yet been evaluated in human trials. One example of a drug developed from the bench to the clinic is the soybean-derived Bowman-Birk inhibitor (BBI), which has been developed as a countermeasure for radiation induced cancer. It was originally identified as a compound/drug that could prevent the radiation induced carcinogenic process in an in vitro assay system in 1975. The first observation that BBI could inhibit carcinogenesis in animals was in 1985. BBI received Investigational New Drug (IND) Status with the U.S. Food and Drug Administration (FDA) in 1992 (after several years of negotiation with the FDA about the potential IND status of the drug), and human trials began at that time. Phase I, II and III human trials utilizing BBI have been performed under several INDs with the FDA, and an ongoing Phase III trial will be ending in the very near future. Thus, the drug has been in development for 35 years at this point, and it is still not a prescription drug on the market which is available for human use. A somewhat less time-consuming process is to evaluate compounds that are on the GRAS (Generally Recognized as Safe) list. These compounds would include some over-the-counter medications, such as antioxidant vitamins utilized in human trials at the levels for which Recommended Dietary Allowances (RDAs) have been established. To determine whether GRAS substances are able to have beneficial effects on radiation induced adverse health effects, it is still likely to be a lengthy process involving many years to potentially decades of human trial work. The human trials necessary to demonstrate "efficacy" for a beneficial effect on the long term adverse health effects of radiation, such as the development of cancer, cataracts, etc., is expected to take particularly long periods of time. To avoid the long time delay in the development of new drugs as countermeasures for radiation induced adverse health effects, the NSBRI Center for Acute Radiation Research (CARR) is currently focused on the use of drugs that have already been approved for human use by the FDA. Currently there are no approved countermeasures for external radiation exposure by the US Army or by NASA. The appropriate medications for symptoms of the Acute Radiation Syndrome (ARS) due to exposure to solar particle event (SPE) radiation are unknown, but there are medications appropriate for ARS symptoms caused by exposure to conventional ra-diation. The Armed Forces Radiobiology Research Institute (AFRRI) has medical guidelines for ARS medications (http://www.afrri.usuhs.mil/outreach/guidance.htm#policies), as does the US Dept. of Health and Human Services (the REMM (Radiation Event Medical Manage-ment) site (http://www.remm.nlm.gov). Supportive care when ARS symptoms develop include the administration of antimicrobial agents (which can include systemic antibiotics [especially those directed at gram-negative bacteria]), antiemetic agents, antidiarrheal agents, fluids, elec-trolytes, analgesic agents and topical burn creams (Waselenko, J.K. et al. Ann. Intern. Med. 140: 1037, 2004). For nausea and vomiting, serotonin receptor antagonists (5HT3 receptor antagonists) are very effective prophylaxis. There are two drugs that have been approved by the FDA (Zofran and Kytril) for radiation induced nausea and vomiting. Kytril (granisetron) is preferred by the US Army and is currently maintained in the US National Stockpile. Both of these drugs are known to stop retching and vomiting when given either before or after irradi-ation, even when vomiting and/or retching are occurring. Immune suppression can occur due to declines in white blood cells and infe

Kennedy, Ann

422

A Survey of Radiation-Induced Bronchiolitis Obliterans Organizing Pneumonia Syndrome After Breast-Conserving Therapy in Japan  

SciTech Connect

Purpose: We observed a rare and unique occurrence of radiation-induced pulmonary injury outside the tangential field for early breast cancer treatment. The findings appeared to be idiopathic and were called radiation-induced bronchiolitis obliterans organizing pneumonia (BOOP) syndrome. We surveyed major hospitals in Japan to review their findings of radiation-induced BOOP, in particular the clinical and pictorial characteristics of the entity. Methods and Materials: We reviewed surveys completed and returned by 20 institutions. The survey responses were based on a total of 37 cases of BOOP syndrome. We also reviewed X-ray and computed tomography scans provided by these institutions. We discussed the information derived from the questionnaire and analyzed patients' characteristics, methods used in the treatment of BOOP syndrome, and prognosis. Results: The incidence of the radiation-induced BOOP syndrome was about 1.8% (37 of 2,056). We did not find a relationship between the characteristics of patients and the occurrence of radiation-induced BOOP syndrome. The pulmonary findings were classified into four patterns on chest computed tomography scans. Progression of the pulmonary lesions observed on chest X-ray was classified into three patterns. Pneumonitis appeared within 6 months after radiotherapy was completed and disappeared within 6-12 months after its onset. At 5-year follow-up, 2 patients had died, 1 of breast cancer and the other of interstitial pneumonitis, which seemed to be idiopathic and unrelated to the radiation-induced BOOP syndrome. Conclusions: Although the incidence of BOOP syndrome and its associated prognosis are not significant, the patients' clinical condition must be carefully followed.

Ogo, Etsuyo [Department of Radiology, Kurume University School of Medicine, Kurume (Japan)], E-mail: etsuogo@med.kurume-u.ac.jp; Komaki, Ritsuko [Department of Radiation Oncology, The University of Texas, M.D. Anderson Cancer Center, Houston, TX (United States); Fujimoto, Kiminori; Uchida, Masafumi; Abe, Toshi [Department of Radiology, Kurume University School of Medicine, Kurume (Japan); Nakamura, Katsumasa [Department of Radiology, Faculty of Medicine, Fukuoka University, Fukuoka (Japan); Mitsumori, Michihide [Department of Radiology, Faculty of Medicine, Kyoto University, Kyoto (Japan); Sekiguchi, Kenji [Department of Radiation Oncology, St. Luke's International Hospital, Tokyo (Japan); Kaneyasu, Yuko [Department of Radiology, Faculty of Medicine, Hiroshima University, Hiroshima (Japan); Hayabuchi, Naofumi [Department of Radiology, Kurume University School of Medicine, Kurume (Japan)

2008-05-01

423

Alpha Lipoic Acid Attenuates Radiation-Induced Thyroid Injury in Rats  

PubMed Central

Exposure of the thyroid to radiation during radiotherapy of the head and neck is often unavoidable. The present study aimed to investigate the protective effect of ?-lipoic acid (ALA) on radiation-induced thyroid injury in rats. Rats were randomly assigned to four groups: healthy controls (CTL), irradiated (RT), received ALA before irradiation (ALA + RT), and received ALA only (ALA, 100 mg/kg, i.p.). ALA was treated at 24 h and 30 minutes prior to irradiation. The neck area including the thyroid gland was evenly irradiated with 2 Gy per minute (total dose of 18 Gy) using a photon 6-MV linear accelerator. Greater numbers of abnormal and unusually small follicles in the irradiated thyroid tissues were observed compared to the controls and the ALA group on days 4 and 7 after irradiation. However, all pathologies were decreased by ALA pretreatment. The quantity of small follicles in the irradiated rats was greater on day 7 than day 4 after irradiation. However, in the ALA-treated irradiated rats, the numbers of small and medium follicles were significantly decreased to a similar degree as in the control and ALA-only groups. The PAS-positive density of the colloid in RT group was decreased significantly compared with all other groups and reversed by ALA pretreatment. The high activity index in the irradiated rats was lowered by ALA treatment. TGF-ß1 immunoreactivity was enhanced in irradiated rats and was more severe on the day 7 after radiation exposure than on day 4. Expression of TGF-ß1 was reduced in the thyroid that had undergone ALA pretreatment. Levels of serum pro-inflammatory cytokines (TNF-?, IL-1ß and IL-6) did not differ significantly between the all groups. This study provides that pretreatment with ALA decreased the severity of radiation-induced thyroid injury by reducing inflammation and fibrotic infiltration and lowering the activity index. Thus, ALA could be used to ameliorate radiation-induced thyroid injury. PMID:25401725

Jung, Jung Hwa; Jung, Jaehoon; Kim, Soo Kyoung; Woo, Seung Hoon; Kang, Ki Mun; Jeong, Bae-Kwon; Jung, Myeong Hee; Kim, Jin Hyun; Hahm, Jong Ryeal

2014-01-01

424

The flavonolignan-silymarin protects enzymatic, hematological, and immune system against ?-radiation-induced toxicity.  

PubMed

The main focus of this study is evaluation of radioprotective efficacy of silymarin, a flavonolignan, against ?-radiation-induced damage to hematological, vital organs (liver and intestine), and immune system. Survival studies revealed that silymarin (administered orally for 3 days) provided maximum protection (67%) at 70 mg/kg body weight (b.wt.) against lethal 9 Gy ?-irradiation (dose reduction factor?=?1.27). The study revealed significant (p < 0.05) changes in levels of catalase (12.57?±?2.58 to 30.24?±?4.89 units), glutathione peroxidase (6.23?±?2.95 to 13.26?±?1.36 µg of reduced glutathione consumed/min/mg protein), glutathione reductase (0.25?±?5.6 to 11.65?±?2.83 pM NADPH consumed/min/mg protein), and superoxide dismutase (11.74?±?0.2 to 16.09?±?3.47 SOD U/mg of protein) activity at 30th day. Silymarin pretreated irradiated group exhibited increased proliferation in erythrocyte count (1.76?±?0.41 × 10(6) to 9.25?±?0.24 × 10(6) ), hemoglobin (2.15?±?0.48g/dL to 14.77?±?0.25g/dL), hematocrit (4.55?±?0.24% to 37.22?±?0.21%), and total leucocyte count (1.4?±?0.15 × 10(6) to 8.31?±?0.47 × 10(6) ) as compared with radiation control group on 15th day. An increase in CD4:CD8 ratio was witnessed (0.2-1%) at 30th day time interval using flow cytometry. Silymarin also countered radiation-induced decrease (p < 0.05) in regulatory T-cells (Tregs ) (11.23% in radiation group at 7th day versus 0.1% in pretreated silymarin irradiated group at 15th day). The results of this study indicate that flavonolignan-silymarin protects enzymatic, hematological, and immune system against ?-radiation-induced toxicity and might prove useful in management of nuclear and radiological emergencies. © 2014 Wiley Periodicals, Inc. Environ Toxicol, 2014. PMID:25411116

Adhikari, Manish; Arora, Rajesh

2014-11-20

425

EGR1 regulates radiation-induced apoptosis in head and neck squamous cell carcinoma.  

PubMed

The transcription factor, early growth response 1 (EGR1) belongs to the early growth response family. EGR1 regulates the t