Intensive Radiation Research Articles

Myeloid-derived suppressor cells in gliomas.

Myeloid-derived suppressor cells (MDSCs) are a heterogeneous population of early myeloid progenitors and precursors at different stages of differentiation into granulocytes, macrophages, and dendritic cells. Blockade of their differentiation into mature myeloid cells in cancer results in an expansion of this population. High-grade gliomas are the most common malignant tumours of the central nervous system (CNS), with a poor prognosis despite intensive radiation and chemotherapy. Histopathological and flow cytometry analyses of human and rodent experimental gliomas revealed the extensive heterogeneity of immune cells infiltrating gliomas and their microenvironment. Immune cell infiltrates consist of: resident (microglia) and peripheral macrophages, granulocytes, myeloid-derived suppressor cells, and T lymphocytes. Intratumoural density of glioma-associated MDSCs correlates positively with the histological grade of gliomas and patient’s survival. MDSCs have the ability to attract T regulatory lymphocytes to the tumour, but block the activation of tumour-reactive CD4+ T helper cells and cytotoxic CD8+ T cells. Immunomodulatory mechanisms employed by malignant gliomas pose an appalling challenge to brain tumour immunotherapy. In this mini-review we describe phenotypic and functional characteristics of MDSCs in humans and rodents, and their occurrence and potential roles in glioma progression. While understanding the complexity of immune cell interactions in the glioma microenvironment is far from being accomplished, there is significant progress that may lead to the development of immunotherapy for gliomas.

Characterization of electromagnetic pulses via arrays on ShenGuang-III laser facility laser

Intensive electromagnetic pulses (EMPs) can be generated from interaction of the ultra-intense lasers and solid targets in inertial confinement fusion (ICF), which will detrimentally affect the data acquisition from some electric components. A diagnostic system for EMP measurement inside and outside the ShenGuang-III facility is designed and fabricated in this study. The experimental results indicate that the peak magnitude of EMP reaches up to 3210.7 kV/m and 6.02 T. The received signals depend most on the antenna and target types. The half-hohlraum generates a more intensive EMP radiation than that from the other targets, and the large planar and medium discone capture much stronger signals than the other antennas. In addition, the mechanisms of EMP generation from different targets are discussed. The resulting conclusion are expected to provide the experimental basis for further EMP shielding design.

Advances in dosimetry and biological predictors of radiation-induced esophagitis.

ObjectiveTo summarize the research progress about the dosimetry and biological predictors of radiation-induced esophagitis.MethodsWe performed a systematic literature review addressing radiation esophagitis in the treatment of lung cancer published between January 2009 and May 2015 in the PubMed full-text database index systems.ResultsTwenty-eight eligible documents were included in the final analysis. Many clinical factors were related to the risk of radiation esophagitis, such as elder patients, concurrent chemoradiotherapy, and the intense radiotherapy regimen (hyperfractionated radiotherapy or stereotactic body radiotherapy). The parameters including Dmax, Dmean, V20, V30, V50, and V55 may be valuable in predicting the occurrence of radiation esophagitis in patients receiving concurrent chemoradiotherapy. Genetic variants in inflammation-related genes are also associated with radiation-induced toxicity.ConclusionDosimetry and biological factors of radiation-induced esophagitis provide clinical information to decrease its occurrence and grade during radiotherapy. More prospective studies are warranted to confirm their prediction efficacy.

Attenuation of glazing energy using linear patterns on the glass surface

Glazing energy resulting from solar radiation can be the main source to vary the thermal field inside of a building. As the glass material is loaded by intensive solar radiation, the glazing energy, greatly induced, will result in the drastic increase in interior temperatures and yield the energy demand for air conditioning loads. Reducing energy consumption is imperative; therefore, this article presents the patterned glass technology which incorporates linearly and uniaxially symmetric patterns throughout the exterior surface of glass to attenuate the solar energy entering indoors. By imposing the patterns over the glass surface, the glazing energy can be reduced due to the increase in the incident angle and the decrease in the solar energy loading on the glass. The thermal performance of the linearly patterned glass is evaluated by computational fluid dynamics technique. Based on computational fluid dynamics–evaluated results, as the patterned glass is applied on the window opening, the interior solar heat is able to be decreased. Moreover, the glazing energy can be strongly associated with the pattern design. Increasing the patterned angle and decreasing the patterned space help reduce solar effect on the interior temperatures.

Spectral and angular radiation characteristics of a charged particle in the plane monochromatic electromagnetic wave

Relying upon the solution of the relativistic equation of charged-particle motion that was obtained by Rukhadze et al., the spectral and angular characteristics of ultra-relativistic intensive radiation of a relativistic charged particle have been studied, the particle being linearly accelerated by a superpower laser pulse. The case where the particle propagates in vacuum without brake light was examined. The interaction of the charged particle with the large-amplitude ultra-short laser pulse was analyzed in details using the relativistic consideration. Formulae for the average radiated power of the relativistic charged particle, depending on the initial conditions, the electromagnetic-wave amplitude, intensity and polarization were obtained. For the case where the laser pulse can be represented by a monochromatic plane wave, analytical expressions for the radiation characteristics were put forward and the phase-angular distributions of relativistic radiated power and intensity were found. The Fourier transform of the electric-intensity radiation field of the charged particle and the particle's spectral density radiation in the field of a plane monochromatic wave for different types of polarization (linear and circular ones) were determined.

In Ukrainian

Within dipole approximation and that of effective mass, the wave function of conduction electron in the quasi-uniform high-frequency electromagnetic field is calculated by the help of nonstationary Schrodinger equation. The kinetics of nonequilibrium interacting quasiparticles in semiconductors in the field of intensive laser radiation is constructed using theory of Dirac quantum transitions.

Resonant multiphoton dissociation of the NO molecule

The multiphoton dissociation of an unexcited NO molecule involving intermediate Rydberg states nlσ(2∑+), nlπ(2П), and nlδ(2Δ), which are populated by a weak probe field and decay owing to nonadiabatic transitions in the predissociation states of valence configurations B′2Δ, L 2П, I 2∑+, and B 2П, has been studied. The role of the ponderomotive interaction that occurs under the simultaneous action of an intensive electromagnetic monochromatic radiation on the studied system has been analyzed. A theory to describe the dynamics of the process has been described. The possibilities of laser stimulation of this process, which consist in the search for ranges of variation in the frequencies and intensities of laser radiation that provide the highest efficiency of the resonant photostimulated process, have been discussed.

PTPS-12INTENSIVE CHEMOTHERAPY FOLLOWED BY REDUCED RADIATION DOSE FOR INTRACRANIAL NON-GERMINOMATOUS GERM CELL TUMORS

PTPS-12. INTENSIVE CHEMOTHERAPY FOLLOWED BY REDUCED RADIATION DOSE FOR INTRACRANIAL NON-GERMINOMATOUS GERM CELL TUMORS Teruyoshi Kageji1, Yoshifumi Mizobuchi1, Kohei Nakajima1, Shinji Nagahiro1, Hiroyoshi Watanabe2, Nami Inoue2, Kazumi Okamura2, and Shoji Kagami2; Department of Neurosurgery, School of Medicine, the University of Tokushima, Tokushima, Japan; Department of Pediatrics, School of Medicine, the University of Tokushima, Tokushima, Japan PURPOSE: It is well known that an intracranial non-germinomatous germ cell tumors (NGGCT), especially the patients who demonstrated high level of serum tumor marker has poor prognosis after standard treatment of chemotherapy and whole brain and spinal radiation. The radiation for childhood can be induce significant neurodevelopmental, neuroendocrine, somatic growth, cognitive impairments and secondary tumors. The objective of this study was to determine whether intensive chemotherapy followed by reduced radiation dose is effective in patients with poor prognosis group of intracranial NGGCT. PATIENTS AND METHODS: We have treated 15 patients (mean age 17 y.o.) with poor prognosis group of an intracranial 24 NGGCTs. The serum b-HCG ranged from 0 to 151052 mIU/ml and AFP ranged from 0 to 4120 ng/ml.The NAT(neo-adjuvant therapy),which isprecedingchemotherapy before surgery, was performed in 9 patients which presented with serum b-HCG of over 500 mIU/ml or AFP 500 ng/ml. As chemo-radiotherapy, the ICE regimen (ifosfamide, cisplatin, etoposide) and whole brain (30Gy) and spinal (24Gy) irradiation was used for 9 patients of poor prognosis group from 1998 to 2006. The intensive regimen (cisplatin, etoposide, cyclophosphamide, bleomycin, carboplatin) and reduced radiotherapy (whole ventricle radiation 30Gy) have been induced for 6 patients since 2007. RESULTS: Mean follow-up period is 76 months. In ICE regimen, five of nine (56%) died (CSF dissemination: 3, secondary GBM: 1, sepsis: 1). In intensive regimen, none died and had serious complications. The initial chemotherapy achieves complete remission in 33%. The 3-year, 5-year and 10-year survival rate of all patients was 68%, 68% and 51%, respectively. The 5-year survival rate of the ICE and intensive regimen was 50% and 100%, respectively. CONCLUSION: Intensive chemotherapy followed by reduced radiation dose and field for poor prognosis group of intracranial NGGCT was safe and expected favorable prognosis and reducing or avoiding late effects. Neuro-Oncology 17:v179–v185, 2015. doi:10.1093/neuonc/nov228.12 Published by Oxford University Press on behalf of the Society for Neuro-Oncology 2015.

S-Adenosylmethionine Affects ERK1/2 and Stat3 Pathways and Induces Apotosis in Osteosarcoma Cells.

Osteosarcoma is a very aggressive bone tumor. Its clinical outcome remains discouraging despite intensive surgery, radiotherapy, and chemotherapy. Thus, novel therapeutic approaches are demanded. S-Adenosylmethionine (AdoMet) is a naturally occurring molecule that is synthesized in our body by methionine adenosyltransferase isoenzymes and is also available as a nutritional supplement. AdoMet is the principal methyl donor in numerous methylation reactions and is involved in many biological functions. Interestingly, AdoMet has been shown to exert antiproliferative action in various cancer cells. However, the underlying molecular mechanisms are just starting to be studied. Here, we investigated the effects of AdoMet on the proliferation of osteosarcoma U2OS cells and the underlying mechanisms. We carried out direct cell number counting, MTT and flow cytometry-based assays, and immunoblotting experiments in response to AdoMet treatment. We found that AdoMet strongly inhibits proliferation of U2OS cells by slowing-down cell cycle progression and by inducing apoptosis. We also report that AdoMet consistently causes an increase of p53 and p21 cell-cycle inhibitor, a decrease of cyclin A and cyclin E protein levels, and a marked increase of pro-apoptotic Bax/Bcl-2 ratio, with caspase-3 activation and PARP cleavage. Moreover, the AdoMet-induced antiproliferative effects were dynamically accompanied by profound changes in ERK1/2 and STAT3 protein and phosphorylation levels. Altogether, our data enforce the evidence of AdoMet acting as a biomolecule with antiproliferative action in osteosarcoma cells, capable of down-regulating ERK1/2 and STAT3 pathways leading to cell cycle inhibition and apoptosis, and provide a rationale for the possible use of AdoMet in osteosarcoma therapy.

Predictors of radiation therapy (RT) use among Medicare patients with metastatic non-small cell lung cancer (NSCLC).

124 Background: Palliative RT can improve quality of life, but also incurs time and financial costs. We evaluated factors associated with use and intensity of palliative RT for metastatic NSCLC. Methods: Using SEER-Medicare data, we identified patients diagnosed with pathologically confirmed stage IV NSCLC from 2004-2011. Receipt of RT and total fractions in the first RT course was collected. Univariable and multivariable logistic regression were used to identify factors associated with RT receipt and higher intensity RT ( > 10 fractions). Models were adjusted for clustering at the county level. Results: Among 53,371 patients with stage IV NSCLC, 39% (20,937) received palliative RT. Among patients receiving RT, 48% (10,048) received > 10 fractions and only 3.5% (724) received single fraction RT. On multivariable analysis, factors associated with greater RT use included younger age group (overall p < .01), lower Charlson comorbidity score (overall p < .01), female gender (OR 1.1, p < .01), married status (OR 1.1, p < .01), South (OR 1.0) and Midwest (OR 1.1) SEER region vs. Northeast (ref) or West (OR 0.9) (overall p < .01), higher radiation oncologist density tertile (OR 1.1, overall p = .02), hospice use (OR 1.47, p < .01), and chemotherapy use (OR 3.61, p < .01). Among patients treated with RT, predictors for > 10 fractions were older age group (overall p = .03), no hospice use (OR 1.1, p < .01), chemotherapy use (OR 1.9, p < .01) and freestanding vs. hospital-based RT facility (OR 1.66, p < .01). Conclusions: A combination of patient, treatment, and health service factors influenced whether a patient received palliative RT. In contrast, most patient factors (except age) did not influence the decision to treat with higher intensity radiation. The receipt of chemotherapy and treatment at a freestanding RT facility were highly predictive for extended RT fractionation, which may have been partially driven by higher reimbursement rates to freestanding facilities during this period.

Abstract 4145: Brain-derived endothelial cells stimulate migration of different human, mouse, and rat glioma cell lines in vivo and in vitro

Abstract Glioblastoma multiforme (GBM) is the most lethal of the human brain tumors. Despite intensive chemotherapy, radiotherapy and surgery, patients usually die within 1-2 years of diagnosis. Glioma cells display the remarkable capacity to infiltrate the brain. They diffusely invade the brain by active cell migration either along blood vessels, white matter tracts, interstitially, or surrounding the meninges. We identified a number of glioma cells (including glioma stem cells) from mouse and human which migrate primarily along the vasculature. Molecular determinants that attract glioma cells to blood vessels remain poorly understood; inhibition of glioma growth along blood vessels could be a potential treatment strategy for GBM. In the present study, we studied whether brain-derived endothelial cells alone, or in combination with other brain cell types attract glioma cells. To do so we tested the ability of human and mouse brain-derived endothelial cells to stimulate the migration of human, mouse and rat-derived glioma cell lines in an in vitro migration assay. We tested the migration of different primary human glioma cell lines like HF2303, MGG8, MSP-12, IN859, IN2045 and U251 in response to mouse brain-derived endothelial (MBVE) cells and mixed mouse brain cells (MMB). Of these, HF2303, MSP-12 cells showed significant migration but not MGG8, IN859, IN2045 and U251 cell lines. Further, Gl26-cit, a mouse glioma and CNS1-cit a rat cell line also exhibited significant migration towards MBVE as well as MMB cells. These results are in line with our in vivo data showing that HF2303, and Gl26-cit, but not MGG8 cells, invade along the blood vessels. Differential migration of various human glioma cell lines in response to MBVE cells is probably due to their heterogeneous growth patterns in vivo. Interestingly, our in vitro data showed that the mouse endothelial cells together with mouse astrocytes, another brain cell type, promote the migration of Gl26-cit cells to a greater extent than the mouse endothelial cells alone. In summary, the behavior of glioma cells in vitro is consistent with their migration patterns in vivo. Further, other brain cell types like astrocytes along with MBVE cells enhance migration of glioma cells. Therefore, we are now using this in vitro model to discover the molecular mechanisms responsible for glioma growth towards blood vessels. This work was supported by NIH-NINDS, the Department of Neurosurgery, and very generous support from Phil F. Jenkins. Citation Format: Viveka N. Yadav, Gregory J. Baker, Samanthi Narayanan, Maria G. Castro, Pedro R. Lowenstein. Brain-derived endothelial cells stimulate migration of different human, mouse, and rat glioma cell lines in vivo and in vitro. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 4145. doi:10.1158/1538-7445.AM2015-4145

Radical esophagectomy in elderly patients with esophageal cancer

BackgroundThe increasing lifespan of the aging population has resulted in an increased number of elderly patients with esophageal cancer. PurposeThis study was conducted to determine the effects of age on outcomes following surgery in elderly patients with esophageal cancer. MethodsPatients with esophageal cancer who received curative esophagectomy between January 2001 and December 2012 were enrolled in this study. The patients were divided into two groups according to their age at diagnosis: Group 1 comprised patients aged ≥70 years and Group 2 comprised patients aged <70 years. Perioperative variables, the length of hospital stay, rates of surgery-related morbidity and mortality, and survival outcomes were analyzed and compared between the two groups. ResultsThe study comprised 185 patients, with 39 patients in Group 1 and 146 patients in Group 2. Perioperative variables, namely pulmonary function, chemoradiotherapy, length of intensive care unit stay (4.5 days vs. 3.1 days), and hospital stay (30.2 days vs. 21.6 days), were significantly different between the two groups. The patients in Group 1 showed higher mortality (7.7% vs. 3.4%) and morbidity (46.1% vs. 29.5%) compared with those in Group 2, with no statistical significance. Cardiopulmonary-related complications (30.8%) following esophagectomy were most frequently observed in elderly patients. With less intensive chemotherapy and/or radiotherapy, the overall survival of the patients in Group 1 was prolonged compared with that of the patients in Group 2 (15.8 months vs. 13.7 months, p = 0.44). Esophagectomy followed by chemoradiotherapy did not yield more positive outcomes than those of esophagectomy alone in patients in Group 1. ConclusionEsophagectomy in elderly patients with esophageal cancer can yield an acceptable outcome and fewer complications than esophagectomy in younger patients. Although reserved physiological functions are typically limited in elderly patients relative to younger patients, elderly patients with resectable esophageal cancer should not be denied esophagectomy.

Long-term Outcome of Extranodal NK/T Cell Lymphoma Patients Treated With Postremission Therapy Using EBV LMP1 and LMP2a-specific CTLs

Extranodal NK/T-cell lymphoma (ENKTCL) is associated with latent Epstein-Barr virus (EBV) infection and frequent relapse even after complete response (CR) to intensive chemotherapy and radiotherapy. The expression of EBV proteins in the tumor provides targets for adoptive immunotherapy with antigen-specific cytotoxic T cells (CTL). To evaluate the efficacy and safety of EBV latent membrane protein (LMP)-1 and LMP-2a-specific CTLs (LMP1/2a CTLs) stimulated with LMP1/2a RNA-transferred dendritic cells, we treated 10 ENKTCL patients who showed complete response to induction therapy. Patients who completed and responded to chemotherapy, radiotherapy, and/or high-dose therapy followed by stem cell transplantation (HDT/SCT) were eligible to receive eight doses of 2 × 107 LMP1/2a CTLs/m2. Following infusion, there were no immediate or delayed toxicities. The 4-year overall survival (OS) and progression-free survival (PFS) were 100%, and 90% (95% CI: 71.4 to 100%) respectively with a median follow-up of 55·5 months. Circulating IFN-γ secreting LMP1 and LMP2a-specific T cells within the peripheral blood corresponded with decline in plasma EBV DNA levels in patients. Adoptive transfer of LMP1/2a CTLs in ENKTCL patients is a safe and effective postremission therapeutic approach. Further randomized studies will be needed to define the role of EBV-CTLs in preventing relapse of ENKTCL.

Ion beam irradiation effect on thermoelectric properties of Bi2Te3 and Sb2Te3 thin films

Thermoelectric energy harvesting is a very promising application in nuclear power plants for self-maintained wireless sensors. However, the effects of intensive radiation on the performance of thermoelectric materials under relevant reactor environments such as energetic neutrons are not fully understood. In this work, radiation effects of bismuth telluride (Bi2Te3) and antimony telluride (Sb2Te3) thermoelectric thin film samples prepared by E-beam evaporation are investigated using Ne2+ ion irradiations at different fluences of 5×1014, 1015, 5×1015 and 1016ions/cm2 with the focus on the transport and structural properties. Electrical conductivities, Seebeck coefficients and power factors are characterized as ion fluence changes. X-ray diffraction (XRD) and transmission electron microscopy (TEM) of the samples are obtained to assess how phase and microstructure influence the transport properties. Carrier concentration and Hall mobility are obtained from Hall effect measurements, which provide further insight into the electrical conductivity and Seebeck coefficient mechanisms. Positive effects of ion irradiations from Ne2+ on thermoelectric material property are observed to increase the power factor to 208% for Bi2Te3 and 337% for Sb2Te3 materials between fluence of 1 and 5×1015cm2, due to the increasing of the electrical conductivity as a result of ionization radiation-enhanced crystallinity. However, under a higher fluence, 5×1015cm2 in this case, the power factor starts to decrease accordingly, limiting the enhancements of thermoelectric materials properties under intensive radiation environment.

Capabilities of stereotactic radiosurgery for patients with liver metastases.

The introduction of innovative technical developments: the three-dimensional planning, using multileaf collimator, simulated by the intensity radiation therapy, improved methods of fixation significantly improved ability of accurate delivering and escalating of doses of ionizing radiation to the selected volume of tissues. This has changed the perception of the role of radiation therapy in the treatment of liver metastases. Foreign authors data suggest the possibility of reaching 95% local control one year after stereotactic radiotherapy, 92% - after two years (and 100% for tumors smaller than 3 cm.) with the development third or higher degree of radiation damage near in 2%. In 2011, after the technical upgrading of Blokhin Cancer center, the method of stereotactic radiosurgery (SBRS) was introduced in clinical practice for the treatment of patients with liver metastases. This method allows to create a high-dose ionizing radiation in metastatic tumor and cause the destruction of the tumor. This is a promising direction in the treatment of metastatic liver cancer significantly expanded the capabilities of the combined treatment. The article provides an overview of the literature on the treatment of liver metastases, and we publish the results of the use of stereotactic radiosurgery at thirty-five patients with liver metastases and clinical case of successful application of this method in patient with significant co-morbidity.

Experimental search for the low-energy nuclear transition in 229Th with undulator radiation

To search for the lowest energy nuclear isomeric transition in 229Th in solid samples, a novel adsorption technique which prepares 229Th atoms on a surface of CaF2 is developed. Adsorbed 229Th is exposed to highly intensive undulator radiation in the wavelength range between 130 and 320 nm, which includes the indirectly measured nuclear resonance wavelength 160(10) nm. After the excitation, fluorescence from the sample is detected with a VUV sensitive photomultiplier tube. No clear signal relating to the nuclear transition is observed and possible reasons are discussed.

Growth in Children Treated for Acute Lymphoblastic Leukemia: Single Institution Report from North India.

Survivors of childhood leukemia are at risk of impaired growth and short stature as adults due to intensive combination chemotherapy and radiation injury. This study was undertaken to evaluate anthropometry in children treated for acute lymphoblastic leukemia (ALL). Children treated for ALL and off treatment for a minimum period of 2years were evaluated for height, weight and BMI. Z scores were calculated for height, weight and BMI: at induction, 6months after starting treatment, at end of treatment and at 2years after completion of therapy. Change in z scores were calculated and compared with CDC criteria and Agarwal standards for Indian children. Fifty two boys and 21 girls were analyzed. Height and weight z scores were seen to show a steep decrease during the initial intensive phase of therapy. The gain in height and weight continued to be slow during therapy and catch up occurred after cessation of therapy. On completion of therapy, patients were shorter, but not significantly so. Girls <9years were significantly shorter. Weight remained on the lower side of normal. Change of z scores was statistically significant for weight at end of treatment (p=0.032) and 2years after completion of treatment (p=0.00). BMI z score increased throughout the study period. Peak growth velocities were also late in the study subjects Anthropometric variables of height, weight and BMI are affected by ALL during therapy. Growth deceleration is maximum during the intensive phase of therapy. Catch up growth occurs but children remain smaller than their peers.

Seasonal behavior and long-term trends of tropospheric ozone, its precursors and chemical conditions over Iran: A view from space

To identify spatial and temporal variations over the Iranian region, this study analyzed tropospheric formaldehyde (HCHO) and nitrogen dioxide (NO2) columns from Ozone Monitoring Instrument (OMI), carbon monoxide (CO) columns from the Measurement of Pollution in the Troposphere (MOPITT), and tropospheric column O3 (TCO) from OMI/MLS (Microwave Limb Sounder) satellites from 2005 to 2012. The study discovered high levels of HCHO (∼12 × 1015 molec./cm2) from plant isoprene emissions in the air above parts of the northern forest of Iran during the summer and from the oxidation of HCHO precursors emitted from petrochemical industrial facilities and biomass burning in South West Iran. This study showed that maximum NO2 levels (∼18 × 1015 molec./cm2) were concentrated in urban cities, indicating the predominance of anthropogenic sources. The results indicate that maximum concentrations were found in the winter, mainly because of weaker local winds and higher heating fuel consumption, in addition to lower hydroxyl radicals (OH). The high CO concentrations (∼2 × 1018 molec./cm2) in the early spring were inferred to mainly originate from a strong continental air mass from anthropogenic CO “hotspots” including regions around Caspian Sea, Europe, and North America, although the external sources of CO were partly suppressed by the Arabian anticyclone and topographic barriers. Variations in the TCO were seen to peak during the summer (∼40 DU), due to intensive solar radiation and stratospheric sources. This study also examined long-term trends in TCO and its precursors over a period of eight years in five urban cities in Iran. To perform the analysis, we estimated seasonal changes and inter-seasonal variations using least-squares harmonic estimation (LS-HE), which reduced uncertainty in the trend by 5–15%. The results showed significant increases in the levels of HCHO (∼0.08 ± 0.06 × 1015 molec./cm2 yr−1), NO2 (∼0.08 ± 0.02 × 1015 molec./cm2 yr−1), and peak annual TCO (∼0.59 ± 0.56 DU yr−1) but decreases in minimum annual TCO (∼−0.42 ± 0.60 DU yr−1) caused by an increase in NO2 species and annual CO (∼−0.95 ± 0.41 × 1016 molec./cm2 yr−1) partly resulting from the transport of reduced CO. The time series of the HCHO/NO2 column ratio (a proxy for the chemical conditions) indicated that during the last decade, the cities of Tehran, Ahvaz, and Isfahan exhibited steady chemical conditions while Tabriz and Mashhad exhibited a change from NOx-saturated/mixed to more NOx-sensitive chemical conditions.

Longitudinal FDG-PET Revealed Regional Functional Heterogeneity of Bone Marrow, Site-Dependent Response to Treatment and Correlation with Hematological Parameters.

Purpose: The purposes of this study were: 1) to show bone marrow (BM) functional heterogeneity, 2) to demonstrate site-dependent responses of BM to cancer treatment utilizing whole body FDG-PET/CT and 3) to identify correlations between FDG uptake in different bone sites and long term complete blood count (CBC).Methods: Thirty two patients who had pre- and post-treatment FDG-PET/CT scans were selected retrospectively. Each patient received either head and neck radiation for cancer of the tongue, or pelvic radiation for rectal or cervical cancer with chemotherapy. Patients had FDG-PET/CT performed prior to the first radiation therapy session and at least one FDG-PET/CT after completion of the prescribed radiation therapy.Results: FDG uptake before radiotherapy was significantly different among bone regions (p < 0.01). This heterogeneity was felt to reflect site-dependent amounts of BM contents possibly due to structural and functional requirements. FDG uptake in the irradiated regions was significantly decreased on the first and second follow-ups after radiation. Feasibly, this could be due to a reduction in the number of active BM cells following intensive radiation in addition to concurrent chemotherapy. Overall, CBC significantly decreased after treatment. Correlation values of each hematological parameter with FDG uptake varied among skeletal regions and scan time points. FDG uptake in sacrum and lumbar regions had better correlation with white blood cells and neutrophils.Conclusions: Longitudinal FDG-PET revealed a regional functional heterogeneity of the BM site-dependent response to treatment. Patients experienced immediate and prolonged marrow metabolic damage that correlates with hematological parameters. FDG-PET/CT may provide additional capabilities to assess BM health.

Diagnosis method of beam for intensive γ-ray radiation field

Diagnosis method of beam for intensive γ-ray radiation field