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1.
Sci Rep ; 13(1): 223, 2023 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-36604532

RESUMO

This study aimed to develop a predictive system for prognostic evaluation of osteosarcoma patients. We obtained osteosarcoma sample data from 1998 to 2016 using SEER*Stat software version 8.3.8, and established a multivariable Cox regression model using R-4.0.3 software. Data were extracted from the Surveillance, Epidemiology, and End Results (SEER) database. The diagnosis of the model was completed through influential cases, proportionality, and multicollinearity. The predictive ability of the model was tested using area under the curve (AUC), calibration curves, and Brier scores. Finally, the bootstrap method was used to internally verify the model. In total, data from 3566 patients with osteosarcoma were included in this study. The multivariate Cox regression model was used to determine the independent prognostic variables. A nomogram and Kaplan-Meier survival curve were established. The AUC and Brier scores indicated that the model had a good predictive calibration. In addition, we found that the radiotherapy appears to be a risk factor of patients with osteosarcoma and made a discussion. We developed a prognostic evaluation system for patients with osteosarcoma for 1-, 3-, and 5-year overall survival with good predictive ability using sample data extracted from the SEER database. This has important clinical significance for the early identification and treatment of high-risk groups of osteosarcoma patients.


Assuntos
Neoplasias Ósseas , Osteossarcoma , Humanos , Área Sob a Curva , Neoplasias Ósseas/mortalidade , Neoplasias Ósseas/radioterapia , Calibragem , Nomogramas , Osteossarcoma/mortalidade , Osteossarcoma/radioterapia , Prognóstico , Programa de SEER , Efeitos da Radiação
2.
J Med Entomol ; 59(1): 320-327, 2022 01 12.
Artigo em Inglês | MEDLINE | ID: mdl-34595516

RESUMO

The sterilization process using gamma irradiation is a crucial component in a program using sterile insect technique (SIT) to control Aedes aegypti. Unfortunately, there is no efficient standard protocol for sterilizing mosquitoes that can produce a high level of sterility while maintaining mating ability and longevity. Therefore, we conducted a study of the critical factors necessary to develop such a standard protocol. In this study, male Ae. aegypti pupae, as well as adults aged 1 d and 3 d, were irradiated using a Gamma-cell 220 irradiator doses of 0, 20, 40, 60, 70, 80, and 100 Gray (Gy). In addition, male Ae. aegypti in the pupal and adult stage aged 1 d were irradiated at a dose of 70 Gy at various temperatures. Changes in emergence rates, longevity, sterility, and mating competitiveness were recorded for each combination of parameters. Results showed that an increase of irradiation dose leads to a rise of induced sterility at all developmental stages, while simultaneously reducing emergence rate, survival, and mating competitiveness. Higher temperatures resulted in increased levels of sterility, reduced longevity, and did not affect the ability to mate. This study found that an irradiation dose of 70 Gy at a temperature between 20.00 and 22.30°C administered in the pupal stage induced a high level of sterility (around 98%), while maintaining mating competitiveness and longevity.


Assuntos
Aedes/efeitos da radiação , Controle de Mosquitos/métodos , Esterilização/métodos , Animais , Longevidade , Mosquitos Vetores/efeitos da radiação , Pupa/efeitos da radiação , Radiação , Efeitos da Radiação , Fatores Sexuais , Comportamento Sexual Animal , Temperatura
3.
Eur J Epidemiol ; 36(4): 401-414, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33742296

RESUMO

Past reports indicated that total-body irradiation at low to moderate doses could be responsible for cardiovascular disease risks, but the mechanism remains unclear. The purpose of this study was to investigate the association between radiation exposure and atherosclerosis, an underlying pathology of cardiovascular diseases, in the Japanese atomic bomb survivors. We performed a cross-sectional study measuring 14 clinical-physiological atherosclerosis indicators during clinical exams from 2010 to 2014 in 3274 participants of the Adult Health Study cohort. Multivariable analyses were performed by using a structural equation model with latent factors representing underlying atherosclerotic pathologies: (1) arterial stiffness, (2) calcification, and (3) plaque as measured with indicators chosen a priori on the basis of clinical-physiological knowledge. Radiation was linearly associated with calcification (standardized coefficient per Gy 0.15, 95 % confidence interval: CI [0.070, 0.23]) and plaque (0.11, 95 % CI [0.029, 0.20]), small associations that were comparable to about 2 years of aging per Gy of radiation exposure, but not with arterial stiffness (0.036, 95 % CI [- 0.025, 0.095]). The model fitted better and had narrower confidence intervals than separate ordinary regression models explaining individual indicators independently. The associations were less evident when the dose range was restricted to a maximum of 2 or 1 Gy. By combining individual clinical-physiological indicators that are correlated because of common, underlying atherosclerotic pathologies, we found a small, but significant association of radiation with atherosclerosis.


Assuntos
Aterosclerose/etiologia , Sobreviventes de Bombas Atômicas , Efeitos da Radiação , Exposição à Radiação/efeitos adversos , Lesões por Radiação/complicações , Adulto , Idoso , Índice Tornozelo-Braço , Espessura Intima-Media Carotídea , Estudos Transversais , Humanos , Japão , Análise de Classes Latentes , Masculino , Pessoa de Meia-Idade , Armas Nucleares , Análise de Onda de Pulso
4.
Int J Radiat Oncol Biol Phys ; 109(5): 1559-1569, 2021 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-33321193

RESUMO

PURPOSE: Local ionizing radiation (IR) can lead to systemic lymphocyte depletion, which is associated with poor survival outcomes in patients with cancer. Interleukin-7 (IL-7) plays an important role in lymphocyte homeostasis; however, its role in alleviating radiation-induced lymphopenia remains unclear. Hence, we established a radiation-induced lymphopenia animal model and evaluated the effect of exogenous IL-7 administration. METHODS: C3H/HeN mice underwent x-ray irradiation of 30 Gy in 10 fractions at the right hind limbs. Next, 10 mg/kg of IL-7 was injected subcutaneously, and the lymphocyte count in blood was measured. Murine hepatocellular carcinoma (HCa-1) cells were inoculated subcutaneously into the right thighs of tumor model mice, which underwent the same treatment. RESULTS: In the naïve mouse model, the decreased CD45+ cell count after irradiation gradually recovered to the initial level over 3 weeks in the IR group, whereas it markedly increased to 373% of the initial level in 1 week in the IR+IL-7 group. Similar trends were observed for the CD3+, CD8+, CD4+, regulatory T cells, and CD19+ B cell counts. Similar findings were observed in the tumor mouse model. CD8+ and CD4+ T cell infiltration in tumor specimens was higher in the IL-7 and IR+IL-7 groups than in the nontreated and IR groups. Tumor growth was significantly more suppressed in the IR+IL-7 group than in the IR group. The median survival time was significantly longer in the IR+IL-7 group (not reached) than in the IR (56 days; P = .0382), IL-7 (36 days; P = .0004), or nontreated groups (36 days; P < .0001). CONCLUSIONS: Administration of exogenous IL-7 after IR not only restored lymphocyte counts but also enhanced the antitumor effect. Exogenous IL-7 can be beneficial in overcoming radiation-induced lymphopenia and in enhancing the treatment outcome in combination with radiation therapy, which needs validation through future clinical studies.


Assuntos
Linfócitos B , Interleucina-7/uso terapêutico , Depleção Linfocítica , Linfopenia/tratamento farmacológico , Linfócitos T , Animais , Linfócitos B/citologia , Linfócitos B/efeitos dos fármacos , Linfócitos B/imunologia , Linfócitos B/efeitos da radiação , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/imunologia , Carcinoma Hepatocelular/radioterapia , Terapia Combinada/métodos , Modelos Animais de Doenças , Ensaio de Imunoadsorção Enzimática , Imuno-Histoquímica , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/imunologia , Neoplasias Hepáticas/radioterapia , Contagem de Linfócitos , Linfopenia/etiologia , Masculino , Camundongos , Camundongos Endogâmicos C3H , Doses de Radiação , Efeitos da Radiação , Linfócitos T/citologia , Linfócitos T/efeitos dos fármacos , Linfócitos T/imunologia , Linfócitos T/efeitos da radiação , Ensaios Antitumorais Modelo de Xenoenxerto
5.
Medicine (Baltimore) ; 99(52): e23766, 2020 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-33350761

RESUMO

OBJECTIVES: This study aimed to evaluate the diagnostic performance of magnetic resonance perfusion-weighted imaging (PWI) as a noninvasive method to assess post-treatment radiation effect and tumor progression in patients with glioma. METHODS: A systematic literature search was performed in the PubMed, Cochrane Library, and Embase databases up to March 2020. The quality of the included studies was assessed by the quality assessment of diagnostic accuracy studies 2. Data were extracted to calculate sensitivity, specificity, and diagnostic odds ratio (DOR), 95% Confidence interval (CI) and analyze the heterogeneity of the studies (Spearman correlation coefficient, I2 test). We performed meta-regression and subgroup analyses to identify the impact of study heterogeneity. RESULTS: Twenty studies were included, with available data for analysis on 939 patients and 968 lesions. All included studies used dynamic susceptibility contrast (DSC) PWI, four also used dynamic contrast-enhanced PWI, and three also used arterial spin marker imaging PWI. When DSC was considered, the pooled sensitivity and specificity were 0.83 (95% CI, 0.79 to 0.86) and 0.83 (95% CI, 0.78 to 0.87), respectively; pooled DOR, 21.31 (95% CI, 13.07 to 34.73); area under the curve (AUC), 0.887; Q∗, 0.8176. In studies using dynamic contrast-enhanced, the pooled sensitivity and specificity were 0.73 (95% CI, 0.66 to 0.80) and 0.80 (95% CI, 0.69 to 0.88), respectively; pooled DOR, 10.83 (95% CI, 2.01 to 58.43); AUC, 0.9416; Q∗, 0.8795. In studies using arterial spin labeling, the pooled sensitivity and specificity were 0.79 (95% CI, 0.69 to 0.87) and 0.78 (95% CI, 0.67 to 0.87), respectively; pooled DOR, 15.63 (95% CI, 4.61 to 53.02); AUC, 0.8786; Q∗, 0.809. CONCLUSIONS: Perfusion magnetic resonance imaging displays moderate overall accuracy in identifying post-treatment radiation effect and tumor progression in patients with glioma. Based on the current evidence, DSC-PWI is a relatively reliable option for assessing tumor progression after glioma radiotherapy.


Assuntos
Neoplasias Encefálicas , Glioma , Angiografia por Ressonância Magnética/métodos , Neoplasias Encefálicas/diagnóstico , Neoplasias Encefálicas/radioterapia , Progressão da Doença , Glioma/diagnóstico , Glioma/radioterapia , Humanos , Estadiamento de Neoplasias , Efeitos da Radiação
6.
Isr J Health Policy Res ; 9(1): 34, 2020 06 30.
Artigo em Inglês | MEDLINE | ID: mdl-32605644

RESUMO

BACKGROUND: Until 1960, hundreds of thousands of children worldwide had been treated for scalp ringworm by epilation via irradiation. The discovery of late health effects in adulthood prompted investigation of the medical aspects of irradiation in childhood and led to the establishment of strict protocols for the use of X-ray irradiation. These studies ignored alopecia, which affects some individuals who underwent irradiation for scalp ringworm as children. This study examined the impact of alopecia due to irradiation for scalp ringworm on the health and psychosocial status of affected women. METHODS: We analysed a random sample of 130 medical files of women recognised by Israel's state committees as suffering from permanent hair loss as a result of scalp ringworm irradiation in childhood. The coded medical data included demographic variables, self-reported mental health conditions, self-reported physical health conditions, self-reported social conditions, and spousal relationship. RESULTS: Compared with the general population of women in Israel, research participants reported significantly higher rates of depression, anti-depressant and/or anti-anxiety drug use, psychotherapy or psychiatric hospitalisation, attempted suicide, migraines, cancer, and divorce. Many described humiliating social experiences due to their appearance, both in childhood and adulthood, that led them to curtail their social interactions. The participants also reported that alopecia negatively affected their spousal relationships. CONCLUSIONS: Life with hair loss from scalp ringworm irradiation in childhood has a negative impact on women's health status and psychosocial state. Health policy-makers must broaden their approach to women who underwent scalp ringworm irradiation by addressing the effects of their hair loss in addition to the effects of the radiation treatment per se. This may be achieved by guiding physicians who provide medical services to these women to take into account the psychosocial and health risks related to hair loss in their diagnosis and treatment as well as by creating a cadre of specially trained mental health professionals who can address their unique psychosocial needs. They must also consider including the specialized mental health services tailored for these women's unique needs in the Healthcare Basket.


Assuntos
Alopecia/etiologia , Efeitos da Radiação , Tinha/complicações , Tinha/terapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Alopecia/fisiopatologia , Feminino , Humanos , Israel , Pessoa de Meia-Idade , Comportamento Sexual/psicologia , Tinha/fisiopatologia
8.
IEEE Pulse ; 11(2): 17-19, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32386133

RESUMO

Despite the advances in developing nuclear weapons and other technologies, not much is known about the long-term effects of radiation on human health. In a world where nuclear energy could help curb carbon emissions, it almost seems paradoxical that its possible long-term risks and impacts to human health are still poorly understood. While researchers have investigated the effects of acute radiation in the aftermath of nuclear incidents such as Chernobyl, Hiroshima, Nagasaki, and Fukushima, more needs to be done to understand the impacts of long-term and low-dose nuclear radiation. Studying the downwinders from the Nevada Test Site could offer one window to investigate those myriad effects.


Assuntos
Estudos de Associação Genética , Medicina de Precisão , Efeitos da Radiação , Exposição à Radiação , Humanos , Japão , Neoplasias/genética , Armas Nucleares , Liberação Nociva de Radioativos , Radiobiologia , Sudoeste dos Estados Unidos , Ucrânia
10.
Sci Rep ; 10(1): 37, 2020 01 08.
Artigo em Inglês | MEDLINE | ID: mdl-31913321

RESUMO

The exposure of germ cells to radiation introduces mutations in the genomes of offspring, and a previous whole-genome sequencing study indicated that the irradiation of mouse sperm induces insertions/deletions (indels) and multisite mutations (clustered single nucleotide variants and indels). However, the current knowledge on the mutation spectra is limited, and the effects of radiation exposure on germ cells at stages other than the sperm stage remain unknown. Here, we performed whole-genome sequencing experiments to investigate the exposure of spermatogonia and mature oocytes. We compared de novo mutations in a total of 24 F1 mice conceived before and after the irradiation of their parents. The results indicated that radiation exposure, 4 Gy of gamma rays, induced 9.6 indels and 2.5 multisite mutations in spermatogonia and 4.7 indels and 3.1 multisite mutations in mature oocytes in the autosomal regions of each F1 individual. Notably, we found two types of deletions, namely, small deletions (mainly 1~12 nucleotides) in non-repeat sequences, many of which showed microhomology at the breakpoint junction, and single-nucleotide deletions in mononucleotide repeat sequences. The results suggest that these deletions and multisite mutations could be a typical signature of mutations induced by parental irradiation in mammals.


Assuntos
Genoma , Mutação , Oócitos/fisiologia , Espermatogônias/fisiologia , Animais , Animais Recém-Nascidos , Feminino , Raios gama , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Taxa de Mutação , Oócitos/efeitos da radiação , Efeitos da Radiação , Radiação Ionizante , Espermatogônias/efeitos da radiação , Sequenciamento Completo do Genoma
11.
Front Immunol ; 11: 617510, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33552081

RESUMO

TLRs, key components of the innate immune system, recognize microbial molecules. However, TLRs also recognize some nonmicrobial molecules. In particular, TLR2 and TLR4 recognize hyaluronic acid, a glycosaminoglycan in the extracellular matrix. In neonatal mice endogenous hyaluronic acid binding to TLR4 drives normal intestinal growth. Hyaluronic acid binding to TLR4 in pericryptal macrophages results in cyclooxygenase2- dependent PGE2 production, which transactivates EGFR in LGR5+ crypt epithelial stem cells leading to increased proliferation. The expanded population of LGR5+ stem cells leads to crypt fission and lengthening of the intestine and colon. Blocking this pathway at any point (TLR4 activation, PGE2 production, EGFR transactivation) results in diminished intestinal and colonic growth. A similar pathway leads to epithelial proliferation in wound repair. The repair phase of dextran sodium sulfate colitis is marked by increased epithelial proliferation. In this model, TLR2 and TLR4 in pericryptal macrophages are activated by microbial products or by host hyaluronic acid, resulting in production of CXCL12, a chemokine. CXCL12 induces the migration of cyclooxygenase2-expressing mesenchymal stem cells from the lamina propria of the upper colonic crypts to a site adjacent to LGR5+ epithelial stem cells. PGE2 released by these mesenchymal stem cells transactivates EGFR in LGR5+ epithelial stem cells leading to increased proliferation. Several TLR2 and TLR4 agonists, including hyaluronic acid, are radioprotective in the intestine through the inhibition of radiation-induced apoptosis in LGR5+ epithelial stem cells. Administration of exogenous TLR2 or TLR4 agonists activates TLR2/TLR4 on pericryptal macrophages inducing CXCL12 production with migration of cyclooxygenase2-expressing mesenchymal stem cells from the lamina propria of the villi to a site adjacent to LGR5+ epithelial stem cells. PGE2 produced by these mesenchymal stem cells, blocks radiation-induced apoptosis in LGR5+ epithelial stem cells by an EGFR mediated pathway.


Assuntos
Intestinos/crescimento & desenvolvimento , Efeitos da Radiação , Cicatrização/fisiologia , Animais , Proliferação de Células/fisiologia , Humanos , Mucosa Intestinal/metabolismo , Receptores Toll-Like/metabolismo
12.
BMC Genomics ; 20(1): 354, 2019 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-31072350

RESUMO

BACKGROUND: Evolution leaves an imprint in species through genetic change. At the molecular level, evolutionary changes can be explored by studying ratios of nucleotide substitutions. The interplay among molecular evolution, derived phenotypes, and ecological ranges can provide insights into adaptive radiations. Caecilians (order Gymnophiona), probably the least known of the major lineages of vertebrates, are limbless tropical amphibians, with adults of most species burrowing in soils (fossoriality). This enigmatic order of amphibians are very distinct phenotypically from other extant amphibians and likely from the ancestor of Lissamphibia, but little to nothing is known about the molecular changes underpinning their radiation. We hypothesised that colonization of various depths of tropical soils and of freshwater habitats presented new ecological opportunities to caecilians. RESULTS: A total of 8540 candidate groups of orthologous genes from transcriptomic data of five species of caecilian amphibians and the genome of the frog Xenopus tropicalis were analysed in order to investigate the genetic machinery behind caecilian diversification. We found a total of 168 protein-coding genes with signatures of positive selection at different evolutionary times during the radiation of caecilians. The majority of these genes were related to functional elements of the cell membrane and extracellular matrix with expression in several different tissues. The first colonization of the tropical soils was connected to the largest number of protein-coding genes under positive selection in our analysis. From the results of our study, we highlighted molecular changes in genes involved in perception, reduction-oxidation processes, and aging that likely were involved in the adaptation to different soil strata. CONCLUSIONS: The genes inferred to have been under positive selection provide valuable insights into caecilian evolution, potentially underpin adaptations of caecilians to their extreme environments, and contribute to a better understanding of fossorial adaptations and molecular evolution in vertebrates.


Assuntos
Proteínas de Anfíbios/genética , Anfíbios/genética , Evolução Molecular , Efeitos da Radiação , Seleção Genética , Proteínas de Anfíbios/efeitos da radiação , Anfíbios/classificação , Animais , Genoma , Anotação de Sequência Molecular , Fenótipo , Filogenia
13.
J Med Econ ; 21(6): 622-628, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29571273

RESUMO

AIMS: To estimate incremental healthcare resource utilization (HRU) and costs associated with skeletal-related events (SREs) secondary to multiple myeloma (MM), and HRU and cost differences in patients with one vs multiple SREs. METHODS: Adults with MM diagnosis between January 1, 2010-December 31, 2014, with benefits coverage ≥12 months pre- and ≥6 months post-diagnosis were followed to last coverage date or December 31, 2015, excluding patients with prior anti-myeloma treatment or cancers. SREs were identified by diagnosis or procedure codes (pathological fracture, spinal cord compression, radiation, or surgery to the bone). SRE patients (index = first post-diagnosis SRE) were propensity score matched 1:1 to patients without SRE (assigned pseudo-index) using baseline characteristics, and ≥1 month of continuous enrollment after index/pseudo-index date was required. Per-patient-per year (PPPY) HRU and costs (2016 US$) were determined for inpatient, outpatient, emergency department (ED), and outpatient pharmacy services during follow-up. Wilcoxon signed rank for means and McNemar's tests for proportions were used to assess differences. Negative binomial regression and generalized linear regression analyses estimated differences in HRU and costs, respectively, for the comparison of single vs multiple SREs. RESULTS: Each cohort included 848 patients (mean age = 61 - 62 years, 57% male) with no significant differences in pre-index demographic or clinical characteristics between matched cohorts. Versus non-SRE patients, SRE patients had significantly higher PPPY use (p < .0001) of inpatient hospitalizations, ED visits, outpatient pharmacy, and higher direct medical costs ($188,723 vs $108,160, p < .0001). Adjusted PPPY total costs were $209,820 in patients with multiple SREs; $159,797 in patients with one SRE. LIMITATIONS: SRE misclassification and residual confounding are possible. CONCLUSIONS: Among patients with MM, average annual costs were substantially higher in patients with SRE compared with matched non-SRE patients. The economic burden of SRE increased further with multiple events.


Assuntos
Doenças Ósseas/economia , Doenças Ósseas/etiologia , Mieloma Múltiplo/complicações , Adulto , Idoso , Comorbidade , Feminino , Fraturas Ósseas/economia , Gastos em Saúde , Recursos em Saúde/economia , Recursos em Saúde/estatística & dados numéricos , Serviços de Saúde/economia , Serviços de Saúde/estatística & dados numéricos , Humanos , Revisão da Utilização de Seguros , Masculino , Pessoa de Meia-Idade , Modelos Econométricos , Pontuação de Propensão , Efeitos da Radiação , Estudos Retrospectivos , Compressão da Medula Espinal/economia , Estados Unidos
14.
Astrobiology ; 18(2): 133-189, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29431479

RESUMO

Proxima Centauri b provides an unprecedented opportunity to understand the evolution and nature of terrestrial planets orbiting M dwarfs. Although Proxima Cen b orbits within its star's habitable zone, multiple plausible evolutionary paths could have generated different environments that may or may not be habitable. Here, we use 1-D coupled climate-photochemical models to generate self-consistent atmospheres for several evolutionary scenarios, including high-O2, high-CO2, and more Earth-like atmospheres, with both oxic and anoxic compositions. We show that these modeled environments can be habitable or uninhabitable at Proxima Cen b's position in the habitable zone. We use radiative transfer models to generate synthetic spectra and thermal phase curves for these simulated environments, and use instrument models to explore our ability to discriminate between possible planetary states. These results are applicable not only to Proxima Cen b but to other terrestrial planets orbiting M dwarfs. Thermal phase curves may provide the first constraint on the existence of an atmosphere. We find that James Webb Space Telescope (JWST) observations longward of 10 µm could characterize atmospheric heat transport and molecular composition. Detection of ocean glint is unlikely with JWST but may be within the reach of larger-aperture telescopes. Direct imaging spectra may detect O4 absorption, which is diagnostic of massive water loss and O2 retention, rather than a photosynthetic biosphere. Similarly, strong CO2 and CO bands at wavelengths shortward of 2.5 µm would indicate a CO2-dominated atmosphere. If the planet is habitable and volatile-rich, direct imaging will be the best means of detecting habitability. Earth-like planets with microbial biospheres may be identified by the presence of CH4-which has a longer atmospheric lifetime under Proxima Centauri's incident UV-and either photosynthetically produced O2 or a hydrocarbon haze layer. Key Words: Planetary habitability and biosignatures-Planetary atmospheres-Exoplanets-Spectroscopic biosignatures-Planetary science-Proxima Centauri b. Astrobiology 18, 133-189.


Assuntos
Evolução Biológica , Exobiologia/métodos , Meio Ambiente Extraterreno , Modelos Biológicos , Planetas , Atmosfera/química , Dióxido de Carbono/química , Monóxido de Carbono/química , Clima , Evolução Planetária , Exobiologia/instrumentação , Temperatura Alta , Oceanos e Mares , Efeitos da Radiação , Telescópios , Água/química
15.
Radiol Med ; 123(3): 185-190, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29086381

RESUMO

PURPOSE: To determine the frequency of unindicated CT phases and the resultant excess of absorbed radiation doses to the uterus and ovaries in women of reproductive age who have undergone CT for non-traumatic abdomino-pelvic emergencies. MATERIALS AND METHODS: We reviewed all abdomino-pelvic CT examinations in women of reproductive age (40 years or less), between 1 June 2012 and 31 January 2015. We evaluated the appropriateness of each CT phase on the basis of clinical indications, according to ACR appropriateness criteria and evidence-based data from the literature. The doses to uterus and ovaries for each phase were calculated with the CTEXPO software, taking into consideration the size-specific dose estimate (SSDE) after measuring the size of every single patient. RESULTS: The final cohort was composed of 76 female patients with an average age of 30 (from 19 to 40 years). In total, 197 CT phases were performed with an average of 2.6 phases per patient. Out of these, 93 (47%) were unindicated with an average of 1.2 inappropriate phases per patient. Unindicated scans were most frequent for appendicitis and unlocalized abdominal pain. The excesses of mean radiation doses to the uterus and ovaries due to unindicated phases were, respectively, of 38 and 33 mSv per patient. CONCLUSION: In our experience, unindicated additional CT phases were numerous with a significant excess radiation dose without an associated clinical benefit. This excess of radiation could have been avoided by widespread adoption of the ACR appropriateness criteria and evidence-based data from the literature.


Assuntos
Abdome/diagnóstico por imagem , Dor Abdominal/diagnóstico por imagem , Apendicite/diagnóstico por imagem , Emergências , Pelve/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Procedimentos Desnecessários , Adulto , Medicina Baseada em Evidências , Feminino , Humanos , Valor Preditivo dos Testes , Doses de Radiação , Efeitos da Radiação , Radiografia Abdominal , Estudos Retrospectivos , Medição de Risco , Sensibilidade e Especificidade , Procedimentos Desnecessários/efeitos adversos
17.
Environ Health Prev Med ; 22(1): 73, 2017 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-29165177

RESUMO

BACKGROUND: This study aimed to examine the level of perception of the technical terms related to the effect of radiation on the human body among residents of the six prefectures of Miyagi, Fukushima, Tokyo, Aichi, Hiroshima, and Nagasaki in Japan. Miyagi and Fukushima were selected as devastated area by Great East Japan Earthquake. Tokyo and Aichi were selected as control. Hiroshima and Nagasaki were selected as the A-bombed area. METHODS: A total of 1030 respondents, 172, 173, 171, 173, 171, and 170, respectively, were surveyed. Differences in the recognition level of technical terms related to the effect of radiation on the human body among residents of the six prefectures were assessed. RESULTS: The highest recognition levels were reported by the respondents from Fukushima (17 items). Those from Miyagi scored the second highest recognition levels (10 out of the 17 terms); the second highest recognition levels for the remaining seven terms were marked by the respondents of Tokyo. Respondents in the Tohoku region had a better recognition for the technical terminology relevant to the effect of radiation on the human body. CONCLUSIONS: Our findings indicate a need for continued, comprehensive risk communication pertaining to health hazards of radiation exposure in Tohoku region. Concerted efforts by central/local governments and other stakeholders are required to allay the anxiety/stress related to radiation exposure among the residents.


Assuntos
Conhecimentos, Atitudes e Prática em Saúde , Efeitos da Radiação , Exposição à Radiação , Humanos , Japão , Exposição à Radiação/efeitos adversos , Terminologia como Assunto
18.
J Radiol Prot ; 37(3): R19-R42, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28703713

RESUMO

This paper presents an overview of the nuclear accident that occurred at the Mayak Production Association (PA) in the Russian Federation on 29 September 1957, often referred to as 'Kyshtym Accident', when 20 MCi (740 PBq) of radionuclides were released by a chemical explosion in a radioactive waste storage tank. 2 MCi (74 PBq) spread beyond the Mayak PA site to form the East Urals Radioactive Trace (EURT). The paper describes the accident and gives brief characteristics of the efficacy of the implemented protective measures that made it possible to considerably reduce doses to the exposed population. The paper also provides retrospective dosimetry estimates for the members of the EURT Cohort (EURTC) which comprises approximately 21 400 people. During the first two years after the accident a decrease in the group average leukocyte (mainly due to neutrophils and lymphocytes) and thrombocyte count was observed in the population. At later dates an increased excess relative risk of solid cancer incidence and mortality was found in the EURTC.


Assuntos
Explosões/história , Neoplasias Induzidas por Radiação/história , Efeitos da Radiação , Proteção Radiológica/história , Liberação Nociva de Radioativos/história , Feminino , História do Século XX , Humanos , Masculino , Neoplasias Induzidas por Radiação/epidemiologia , Radiometria/história , Federação Russa/epidemiologia
20.
Appl Physiol Nutr Metab ; 41(12): 1248-1254, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27863208

RESUMO

The cucurbits (prebiotics) were investigated as novel agents for radio-modification against gastrointestinal injury. The cell-cycle fractions and DNA damage were monitored in HCT-15 cells. A cucurbit extract was added to culture medium 2 h before irradiation (6 Gy) and was substituted by fresh medium at 4 h post-irradiation. The whole extract of the fruits of Lagenaria siceraria, Luffa cylindrica, or Cucurbita pepo extract enhanced G2 fractions (42%, 34%, and 37%, respectively) as compared with control (20%) and irradiated control (31%). With cucurbits, the comet tail length remained shorter (L. siceraria, 28 µm; L. cylindrica, 34.2 µm; C. pepo, 36.75 µm) than irradiated control (41.75 µm). For in vivo studies, L. siceraria extract (2 mg/kg body weight) was administered orally to mice at 2 h before and 4 and 24 h after whole-body irradiation (10 Gy). L. siceraria treatment restored the glutathione contents to 48.8 µmol/gm as compared with control (27.6 µmol/gm) and irradiated control (19.6 µmol/gm). Irradiation reduced the villi height from 379 to 350 µm and width from 54 to 27 µm. L. siceraria administration countered the radiation effects (length, 366 µm; width, 30 µm, respectively) and improved the villi morphology and tight junction integrity. This study reveals the therapeutic potential of cucurbits against radiation-induced gastrointestinal injury.


Assuntos
Frutas/química , Gastroenteropatias/prevenção & controle , Lagenidium/química , Extratos Vegetais/uso terapêutico , Prebióticos , Lesões Experimentais por Radiação/prevenção & controle , Protetores contra Radiação/uso terapêutico , Animais , Linhagem Celular Tumoral , Cucurbita/química , Dano ao DNA , Frutas/economia , Fase G2/efeitos da radiação , Gastroenteropatias/dietoterapia , Gastroenteropatias/metabolismo , Gastroenteropatias/patologia , Glutationa/metabolismo , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patologia , Mucosa Intestinal/efeitos da radiação , Mucosa Intestinal/ultraestrutura , Luffa/química , Masculino , Camundongos , Microvilosidades/metabolismo , Microvilosidades/patologia , Microvilosidades/efeitos da radiação , Microvilosidades/ultraestrutura , Extratos Vegetais/metabolismo , Efeitos da Radiação , Lesões Experimentais por Radiação/dietoterapia , Lesões Experimentais por Radiação/metabolismo , Lesões Experimentais por Radiação/patologia , Protetores contra Radiação/metabolismo , Distribuição Aleatória , Análise de Sobrevida , Junções Íntimas/metabolismo , Junções Íntimas/patologia , Junções Íntimas/efeitos da radiação , Junções Íntimas/ultraestrutura
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