Oxygen Tension of Cervical Carcinoma during the Early Phase of External Irradiation

1968 ◽  
Vol 21 (sup106) ◽  
pp. 159-166
Author(s):  
Per Bergsjø ◽  
J. C. Evans
Reproduction ◽  
2021 ◽  
Vol 161 (4) ◽  
pp. 353-363
Author(s):  
Mun-Hyeong Lee ◽  
Pil-Soo Jeong ◽  
Bo-Woong Sim ◽  
Hyo-Gu Kang ◽  
Min Ju Kim ◽  
...  

In the mammalian female reproductive tract, physiological oxygen tension is lower than that of the atmosphere. Therefore, to mimic in vivo conditions during in vitro culture (IVC) of mammalian early embryos, 5% oxygen has been extensively used instead of 20%. However, the potential effect of hypoxia on the yield of early embryos with high developmental competence remains unknown or controversial, especially in pigs. In the present study, we examined the effects of low oxygen tension under different oxygen tension levels on early developmental competence of parthenogenetically activated (PA) and in vitro-fertilized (IVF) porcine embryos. Unlike the 5% and 20% oxygen groups, exposure of PA embryos to 1% oxygen tension, especially in early-phase IVC (0–2 days), greatly decreased several developmental competence parameters including blastocyst formation rate, blastocyst size, total cell number, inner cell mass (ICM) to trophectoderm (TE) ratio, and cellular survival rate. In contrast, 1% oxygen tension did not affect developmental parameters during the middle (2–4 days) and late phases (4–6 days) of IVC. Interestingly, induction of autophagy by rapamycin treatment markedly restored the developmental parameters of PA and IVF embryos cultured with 1% oxygen tension during early-phase IVC, to meet the levels of the other groups. Together, these results suggest that the early development of porcine embryos depends on crosstalk between oxygen tension and autophagy. Future studies of this relationship should explore the developmental events governing early embryonic development to produce embryos with high developmental competence in vitro.


Author(s):  
Constantine Papavasiliou ◽  
Demetrios Yiogarakis ◽  
John Pappas ◽  
Antonios Keramopoulos

2002 ◽  
Vol 12 (1) ◽  
pp. 18-21 ◽  
Author(s):  
P. W Grigsby ◽  
L Portelance ◽  
J. F Williamson

Abstract.Grigsby PW, Portelance L, Williamson JF. High dose rate (HDR) cervical ring applicator to control bleeding from cervical carcinoma.The objective of this study was to evaluate the use of the high dose rate (HDR) cervical ring applicator to control acute cervical bleeding from carcinoma of the uterine cervix. This study consists of 15 patients presenting with invasive carcinoma of the uterine cervix with acute vaginal bleeding requiring transfusion. Initial irradiation, delivered emergently because of vaginal bleeding, consisted of two fractions (5 Gy each fraction to the surface of the cervix) utilizing the HDR intracavitary vaginal ring applicator. Two fractions were administered at one week intervals for a total of 10 Gy to the surface of the cervix. Irradiation doses from the HDR ring applications were not considered into the composite total dose to point A. Diagnostic imaging evaluation and initiation of external irradiation were commenced during this initial weekly interval between fractions. Vaginal bleeding requiring no additional transfusions was achieved in 93% (14/15) of patients. No acute or long-term Grades 3, 4, or 5 bowel or bladder sequelae were noted. In conclusion, HDR cervical ring brachytherapy is effective in controlling acute vaginal bleeding and can be delivered without undue acute or long-term toxicity.


2018 ◽  
Vol 185 (1) ◽  
pp. 96-108
Author(s):  
Cécile Challeton-de Vathaire ◽  
Emmanuel Quentric ◽  
Damien Didier ◽  
Eric Blanchardon ◽  
Estelle Davesne ◽  
...  

Abstract In the early phase of a nuclear reactor accident, in-vivo monitoring of impacted population would be highly useful to detect potential contamination during the passage of the cloud and to estimate the dose from inhalation of measured radionuclides. However, it would be important to take into account other exposure components: (1) inhalation of unmeasured radionuclides and (2) external irradiation from the plume and from the radionuclides deposited on the soil. This article presents a methodology to calculate coefficients used to convert in-vivo measurement results directly into doses, not only from the measured radionuclides but from all sources of exposure according to model-based projected doses. This early interpretation of in-vivo measurements will provide an initial indication of individual exposure levels. As an illustration, the methodology is applied to two scenarios of accidents affecting a nuclear power plant: a loss-of-coolant accident leading to core meltdown and a steam generator tube rupture accident.


Sign in / Sign up

Export Citation Format

Share Document