Early and continuing effects of combined alpha and beta irradiation of the lung

phase II report
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Division of Regulatory Applications, Office of Nuclear Regulatory Research, U.S. Nuclear Regulatory Commission , Washington, DC
Lungs -- Effect of radiation on., Rats -- Effect of radiation on., Radiation -- Physiological ef
Statementprepared by B.R. Scott ... [et al.].
ContributionsScott, B. R., U.S. Nuclear Regulatory Commission. Office of Nuclear Regulatory Research. Division of Regulatory Applications., Inhalation Toxicology Research Institute.
The Physical Object
Paginationix, 39 p. :
ID Numbers
Open LibraryOL17661968M

This report summarizes an inhalation exposure experiment that concerns early and continuing effects of combined alpha and beta irradiation of the lung of rats.

Both morbidity at 18 months and mortality within 18 months after exposure were examined for rats exposed to the beta-emitter /sup /Pm, the alpha-emitter /sup /Pu, or both combined.

Radiation sickness is the cumulative effect of all this damage on a human body that's been bombarded with radiation. Ionizing radiation comes in three flavors: alpha particles, beta particles and gamma rays.

Alpha particles are the least dangerous in terms of external exposure. Each particle contains a pair of neutrons and a pair of : Ed Grabianowski. The most general case of radiation only needs local thermodynamic equilibrium and weak inter-particle interactions to keep extensivity (Badescu, a).The ratio β/α depends on the temperature T and the vectors p g and p n containing parameters dependent on the system (see Badescu, a).Specific results have been reported for phonons, electrons and π 0 mesons (Badescu, a), blackbody.

Prediction of biological response after irradiation has been a challenge since the discovery of X-rays and radium. In the early days Early and continuing effects of combined alpha and beta irradiation of the lung book radiotherapy it became clear that the biological effect of irradiation was not only determined by the total dose, but also by the characteristics of the treatment schedule such as fraction dose, dose rate and overall treatment time [].Cited by:   The difference in the interpretations is that if redistribution were the principal cause, then changing the overall treatment time by changing the interval between fractions should result in a change in slope of the isoeffect curve for early effects Alpha, beta Cited by: Alpha and beta dual receptor blockers are a subclass of beta blockers which are commonly used to treat high blood pressure (BP).

Drugs in this class include carvedilol (Coreg), labetalol (Trandate) and dilevalol (Unicard). We searched for and found all the relevant studies to examine how well this class of drugs lowered blood pressure. Introduction. Lung cancer (LC) remains the most common cancer, with approximately million cases diagnosed in worldwide ().Due to earlier detection, advances in staging, increasing use of combined modality treatment, and advances in radiation therapy (RT), patients with LC are also living longer ().Unfortunately, approximately 50% will experience locoregional, marginal and/or distant.

When beta (β) is large, both mis-repair and good-repair are high. It is the mis-repair that causes the cell survival curve to bend downward [1]. It is the " dose for which the number of acutely responding cell deaths is equal to the number of late-responding cell deaths (the dose for which the linear and quadratic components of cell death are.

Estimation of the alpha / beta ratio for lung injury based on direct measurements of radiotherapy (RT)-induced reductions in regional perfusion in human patients Bridget Koontz, Su-min Zhou, Elizabeth Evans, Zeljko Vujaskovic, Ron Jazczack, Terence Wong, and Lawrence Marks Department of Radiation Oncology, Duke University Medical Center, Durham.

The use of radiation therapy to treat cancer inevitably involves exposure of normal tissues. As a result, patients may experience symptoms associated with damage to normal tissue during the course of therapy for a few weeks after therapy or months or years later.

Symptoms may be due to cell death or wound healing initiated within irradiated tissue, and may be precipitated by exposure to. Alpha, beta, and gamma radiation have very different routes of exposure and effects on tissue. All ionizing radiations can be mutagenic and exposure increases the risk of cancer (WHO, ; EPA, ).Alpha particles are highly ionizing but have very low tissue penetration; an alpha particle cannot penetrate the upper layers of the skin.

Lung tissue At 2 mo after irradiation, IL-6 mRNA was increased (×20) in the whole lung of mice compared with controls. Tabata et al. TGF-β C57BL/6 Thorax X-ray/ Gy 24, 48, 72 h, 1, 2 and 3 w RT-PCR Lung tissue The TGF-β1 level showed an early increase at 48 h post-irradiation and remained elevated until 1 w.

Machtay et al. In rats, partial radiation of the lungs led to effects in the shielded lung volume that was adjacent but external to the targeted field.

Increased expression of tumour necrosis factor alpha (TNF-α), interleukin-1 alpha, interleukin-1 beta, interleukin-6, and transforming growth factor beta (TGF-β) were detected. INTRODUCTION. Early radiation dermatitis and late radiation fibrosis are consequences of radiation therapy that can produce nonhealing wounds, pain and functional problems ().To date, the only proven approaches for reducing radiation toxicity are to decrease the treatment field size, fraction size or total dose or to use antioxidants (6, 7).Although more recent radiation therapy schedules have.

Conclusion. Fitted radiobiological parameters were consistent with known carbon in vitro radiobiology, and the resulting dose–response curve well-fitted the reported data over a wide range of dose-fractionation schemes. The same model, with only a few fitted parameters of clear mechanistic meaning, thus synthesizes both photon radiotherapy and CIRT clinical experience with early stage lung.

Lung cancer or lung carcinoma is a malignant tumor of the lung that is characterized by uncontrolled growth of cells in the lung tissues [1]. It a predominant public health problem worldwide is. The combination of the two drugs, at the doses used, demonstrated effects that were generally greater than either drug alone suggesting strong potential for mitigating of radiation-induced lung damage following exposure in an event like terrorist attack or nuclear accident or for future clinical trial of these drugs among patients.

Details Early and continuing effects of combined alpha and beta irradiation of the lung EPUB

Cell Irradiation Procedures. The α-particle source was described previously ().Briefly, the source is a sealed planar, custom-manufactured Am foil (NRD, LLC, Grand Island, NY).

The Am foil emits α particles at an average energy of MeV and an average LET of keV/µm. For α-particle irradiations, a custom-made cell culture dish with a replaceable mylar bottom was used.

* beta radiation is in between alpha and gamma in terms of its penetrating power; typically it goes a meter or so in air * like all kinds of radioactive decay, beta decay occurs because the. Radiation-induced lung injury (RILI) encompasses any lung toxicity induced by radiation therapy (RT) and manifests acutely as radiation pneumonitis and chronically as radiation pulmonary fibrosis.

Because most patients with thoracic and breast malignancies are expected to undergo RT in their lifetime, many with curative intent, the population at risk is significant.

Description Early and continuing effects of combined alpha and beta irradiation of the lung FB2

Average combined dose (initial + retreatment) (range: - 16,). 1 pt retreated twice. Median time to recurrence was 10 months. Very few pts received adjuvant chemotherapy (no concurrent chemo). PMID "Lung cancer: retreatment of local recurrence after definitive irradiation." (Green N, Cancer.

Mar 1;49(5)). The effect of prophylactic cranial irradiation on survival in this meta-analysis (an absolute improvement of percent [from percent in the control group to percent in the treatment. Furthermore, alpha-smooth muscle actin (αSMA) staining at 30 weeks showed that FG reduced irradiation-induced myofibroblast abundance as a potential mechanism for FG’s antifibrotic effects because myofibroblasts are involved in ECM deposition and lung remodeling in lung fibrosis.

Moreover, several studies have reported the synergistic therapeutic effects of curcumin in combination with other natural or synthetic compounds (Singh et al., ).

Overall, the well‐documented anti‐inflammatory and immunomodulatory effects of curcumin along with the evidence on the anti‐fibrotic and pulmonoprotective effects of this. Early experience in brain metastases (Lippitz et al ) and lung (Murray et al ) has shown good outcomes for treatments with 1–3 fractions of 15–20 Gy, making use of advanced delivery techniques such as volumetric modulated arc therapy (VMAT), Tomotherapy or Gammaknife to precisely target dose delivery to tumour volumes.

Introduction. The lung is one of the most susceptible organs to potentially debilitating radiation toxicity. The mechanisms involved in the initiation and perpetuation of radiation-induced lung injury remain incompletely understood but the functional effects of irradiation on lung.

Irradiation is about the radiation itself like alpha, beta or gamma. Radiation can’t travel far so is not a risk over long distances. Alpha particles cause lots of ionization in a short distance. Alpha radiation is up to twenty times more damaging than other kinds because it tears up atoms so much.

Defensins can be classified into alpha and beta families. Alpha-defensins (α-defensins) are found in neutrophils, macrophages, and Paneth cells in the intestine.

Paneth cell defensins are called crypticidins and serve to reduce the number of bacteria in the intestinal lumen. Beta-defensins (β-defensins) are secreted by most leukocytes and. Alpha decay or α-decay is a type of radioactive decay in which an atomic nucleus emits an alpha particle (helium nucleus) and thereby transforms or 'decays' into a different atomic nucleus, with a mass number that is reduced by four and an atomic number that is reduced by two.

An alpha particle is identical to the nucleus of a helium-4 atom, which consists of two protons and two neutrons. Alpha particle–induced cell damage can generate antigen-specific T-cell responses, and the immunostimulatory environment created by TαT can be exploited to achieve a robust and effective antitumor response.

16 In addition, alpha particle irradiation can induce a number of off-target effects, including the generation of radical oxygen species.

Glucan and irradiation. Exposure to irradiation results in three syndromes, the CNS, the gastrointestinal, and the hemopoietic. The most serious is the last one, because it is already evoked by the lowest radiation doses ().Irradiation of the whole body results in hemopoietic stem cell depletion, which is accompanied by the loss of terminally differentiated leukocytes (), lymphoid cells, and.There was increased uptake in the gut, bone and thymus at this early time.

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Injury to the lung occurs later (1–3). Our SPECT results using 99m Tc-duramycin suggest ongoing apoptosis in the lung beginning around 2 weeks post-irradiation and continuing (Figure 3).

Albanes D, Heinonen O, Taylor P, et al: Alpha-tocopherol and beta-carotene supplements and lung cancer incidence in the alpha-tocopherol, beta-carotene cancer prevention study: Effects of baseline characteristics and study compliance.

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