scholarly journals Effects of HIF-1α Inhibitors on the Response of Experimental Tumors to High-dose Hypo-fractionated Irradiation (SBRT/SRS)

2017 ◽  
Vol 99 (2) ◽  
pp. E584
Author(s):  
C.W. Song ◽  
L.C. Cho ◽  
K.E. Dusenbery ◽  
M. Kim ◽  
R.J. Griffin ◽  
...  
Keyword(s):  
High Dose ◽  
Fractionated Irradiation ◽  
Experimental Tumors

Cauda equina tolerance to high-dose fractionated irradiation

2006 ◽  
Vol 64 (1) ◽  
pp. 251-257 ◽  
Author(s):  
Richard S. Pieters ◽  
Andrzej Niemierko ◽  
Barbara C. Fullerton ◽  
John E. Munzenrider
Keyword(s):  
Cauda Equina ◽  
High Dose ◽  
Fractionated Irradiation

scholarly journals Evaluasi Dosis Fraksionasi Sinar Gamma dalam Melemahkan Parasit Malaria Plasmodium berghei pada Mencit untuk Pengembangan Vaksin Iradiasi

2019 ◽  
Vol 8 (1) ◽  
pp. 33-41
Author(s):  
Mukh Syaifudin ◽  
Hartati Mahmudah ◽  
Teja Kisnanto ◽  
Devita Tetriana ◽  
Siti Nurhayati ◽  
...  
Keyword(s):  
Body Weight ◽  
Plasmodium Berghei ◽  
Malaria Vaccine ◽  
High Dose ◽  
Fractionated Irradiation ◽  
Macroscopic Appearance ◽  
Treatment Groups ◽  
Blood Smears ◽  
Weight Stability ◽  
Thin Blood Smears

Abstract Malaria is still a big problem in Indonesia so that the development of vaccine is urgently needed. However, the immunity is not fully obtained in host that may be due to high dose of irradiation to parasites. This study aimed to determine the infectiveness of Plasmodium berghei malaria parasite in mice after being irradiated with gamma fractionated dose of 0 Gy, 100+50, 100+75 and 100+100 Gy at a dose rate of 717 Gy/h. Observation of the percentage of parasitic appearance forms (parasitemia) such as trophozoite (including ring) and schizont was done on thin blood smears stained by Giemsa from observation day 2 to 20 post injection. The results showed that fractionated irradiation was effectively suppressed the growth of parasites in the blood of mice for all treatment groups except the fractionation dose of 100+75 Gy. Mice injected with a dose of 100+100 Gy have a stable body weight during days of observation, supported by a relatively normal macroscopic appearance of the liver and spleen. It was concluded that fractionated dose of 100+100 Gy is most effectively weakened the parasite for malaria vaccine material supported by body weight stability and better condition of liver-lymph organ. AbstrakMalaria masih merupakan pemasalahan besar di Indonesia sehingga pengembangan vaksin sangat diperlukan. Akan tetapi, imunitas pada inang belum sepenuhnya diperoleh yang kemungkinan disebabkan oleh tingginya dosis iradiasi pada parasit. Penelitian ini bertujuan untuk mengetahui daya infektif parasit malaria Plasmodium berghei pada mencit setelah diiradiasi gamma fraksinasi 0 Gy, 100+50, 100+75 dan 100+100 Gy pada laju dosis 717 Gy/jam. Diamati persentase kemunculan bentuk-bentuk parasit (parasitemia) seperti tropozoit (termasuk cincin) dan skizon pada apusan darah tipis yang diwarnai Giemsa, dari hari pengamatan ke-2 hingga 20 pasca penyuntikan. Hasil penelitian menunjukkan bahwa iradiasi fraksinasi efektif menekan pertumbuhan parasit dalam darah mencit untuk semua perlakuan kecuali dosis fraksinasi 100+75 Gy. Mencit disuntik dosis 100+100 Gy memiliki berat badan yang stabil selama pengamatan, didukung oleh tampilan makroskopis hati dan limpa yang relatif normal. Disimpulkan bahwa iradiasi fraksinasi 100+100 Gy paling efektif melemahkan parasit sebagai bahan vaksin malaria, didukung oleh kestabilan berat badan dan kondisi organ hati-limpa yang lebih baik.

Electron Beam Damage of Biomolecules Assessed by Energy Loss Spectroscopy

1978 ◽  
Vol 36 (3) ◽  
pp. 61-69
Author(s):  
M. Isaacson ◽  
M.L. Collins ◽  
M. Listvan
Keyword(s):  
Electron Microscopy ◽  
Radiation Damage ◽  
Structural Integrity ◽  
Analytical Electron Microscopy ◽  
High Dose ◽  
Dose Rates ◽  
Special Cases ◽  
Analytical Electron ◽  
Atom Migration ◽  
Beam Damage

Over the past five years it has become evident that radiation damage provides the fundamental limit to the study of blomolecular structure by electron microscopy. In some special cases structural determinations at very low doses can be achieved through superposition techniques to study periodic (Unwin & Henderson, 1975) and nonperiodic (Saxton & Frank, 1977) specimens. In addition, protection methods such as glucose embedding (Unwin & Henderson, 1975) and maintenance of specimen hydration at low temperatures (Taylor & Glaeser, 1976) have also shown promise. Despite these successes, the basic nature of radiation damage in the electron microscope is far from clear. In general we cannot predict exactly how different structures will behave during electron Irradiation at high dose rates. Moreover, with the rapid rise of analytical electron microscopy over the last few years, nvicroscopists are becoming concerned with questions of compositional as well as structural integrity. It is important to measure changes in elemental composition arising from atom migration in or loss from the specimen as a result of electron bombardment.

Electron-diffraction studies in synthetic polymer materials

1983 ◽  
Vol 41 ◽  
pp. 362-365
Author(s):  
D.T. Grubb
Keyword(s):  
Electron Diffraction ◽  
Synthetic Polymer ◽  
Polymer Materials ◽  
Crystallographic Structure ◽  
High Dose ◽  
Electron Dose ◽  
Dose Rates ◽  
First Case ◽  
Diffraction Patterns ◽  
The Many

Diffraction studies in polymeric and other beam sensitive materials may bring to mind the many experiments where diffracted intensity has been used as a measure of the electron dose required to destroy fine structure in the TEM. But this paper is concerned with a range of cases where the diffraction pattern itself contains the important information.In the first case, electron diffraction from paraffins, degraded polyethylene and polyethylene single crystals, all the samples are highly ordered, and their crystallographic structure is well known. The diffraction patterns fade on irradiation and may also change considerably in a-spacing, increasing the unit cell volume on irradiation. The effect is large and continuous far C94H190 paraffin and for PE, while for shorter chains to C 28H58 the change is less, levelling off at high dose, Fig.l. It is also found that the change in a-spacing increases at higher dose rates and at higher irradiation temperatures.

Microprobe analysis of inclusion bodies related to two benzofuran derivatives

1987 ◽  
Vol 45 ◽  
pp. 672-673
Author(s):  
T. L. Benning ◽  
P. Ingram ◽  
J. D. Shelburne
Keyword(s):  
Inclusion Bodies ◽  
Uranyl Acetate ◽  
Multiple Organ ◽  
High Dose ◽  
En Bloc ◽  
Tissue Samples ◽  
Transmission Electron ◽  
Organ Systems ◽  
Dense Inclusion ◽  
Melanin Complex

Two benzofuran derivatives, chlorpromazine and amiodarone, are known to produce inclusion bodies in human tissues. Prolonged high dose chlorpromazine therapy causes hyperpigmentation of the skin with electron-dense inclusion bodies present in dermal histiocytes and endothelial cells ultrastructurally. The nature of the deposits is not known although a drug-melanin complex has been hypothesized. Amiodarone may also cause cutaneous hyperpigmentation and lamellar lysosomal inclusion bodies have been demonstrated within the cells of multiple organ systems. These lamellar bodies are believed to be the product of an amiodarone-induced phospholipid storage disorder. We performed transmission electron microscopy (TEM) and energy dispersive x-ray microanalysis (EDXA) on tissue samples from patients treated with these drugs, attempting to detect the sulfur atom of chlorpromazine and the iodine atom of amiodarone within their respective inclusion bodies.A skin biopsy from a patient with hyperpigmentation due to prolonged chlorpromazine therapy was fixed in 4% glutaraldehyde and processed without osmium tetroxide or en bloc uranyl acetate for Epon embedding.

Acetaminophen: Neonatal hepatotoxicity due to late pregnancy exposure

1987 ◽  
Vol 45 ◽  
pp. 718-719
Author(s):  
G.A. Miranda ◽  
M.A. Arroyo ◽  
C.A. Lucio ◽  
M. Mongeotti ◽  
S.S. Poolsawat
Keyword(s):  
Low Dose ◽  
Fetal Liver ◽  
Late Pregnancy ◽  
Toxic Chemicals ◽  
Control Group ◽  
High Dose ◽  
Over The Counter ◽  
Liver And Kidney ◽  
Neonatal Liver ◽  
Childbearing Women

Exposure to drugs and toxic chemicals, during late pregnancy, is a common occurrence in childbearing women. Some studies have reported that more than 90% of pregnant women use at least 1 prescription; of this, 60% used more than one. Another study indicated that 80% of the consumed drugs were not prescribed, and of this figure, 95% were “over-the-counter” drugs. Acetaminophen, the safest of all over-the-counter drugs, has been reported to induce fetal liver necrosis in man and animals and to have abortifacient and embryocidal action in mice. This study examines the degree to which acetaminophen affects the neonatal liver and kidney, when a fatty diet is simultaneously fed to the mother during late pregnancy.Timed Swiss Webster female mice were gavaged during late pregnancy (days 16-19) with fat suspended acetaminophen at a high dose, HD = 84.50 mg/kg, and a low dose, LD = 42.25 mg/kg; a control group received fat alone.

Analysis of Silicon-On-Insulator Structures Formed By Oxygen Ion Implantation

1985 ◽  
Vol 43 ◽  
pp. 300-301
Author(s):  
N. Lewis ◽  
E. L. Hall ◽  
A. Mogro-Campero ◽  
R. P. Love
Keyword(s):  
Ion Implantation ◽  
Single Crystal ◽  
Single Crystal Silicon ◽  
Silicon Layer ◽  
Device Fabrication ◽  
Silicon On Insulator ◽  
High Dose ◽  
Crystal Silicon ◽  
Oxygen Ion ◽  
Oxygen Ion Implantation

The formation of buried oxide structures in single crystal silicon by high-dose oxygen ion implantation has received considerable attention recently for applications in advanced electronic device fabrication. This process is performed in a vacuum, and under the proper implantation conditions results in a silicon-on-insulator (SOI) structure with a top single crystal silicon layer on an amorphous silicon dioxide layer. The top Si layer has the same orientation as the silicon substrate. The quality of the outermost portion of the Si top layer is important in device fabrication since it either can be used directly to build devices, or epitaxial Si may be grown on this layer. Therefore, careful characterization of the results of the ion implantation process is essential.

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