Radiolabeling and Bio-distribution study of ICD-85 with Technetium-99m as a cancer treatment agent in mice

     ICD-85 is a combination of three poly-peptides, ranging from 10,000 to 30,000 Dalton, derived from the venoms of an Iranian brown snake (Agkistrodon halys) and a yellow scorpion (Hemiscorpius lepturus). Labeling of this ICD-85 was successfully achieved with 99mTc, through direct method using SnF2 as reducing agent. Labeled ICD-85 was injected into mice to determine the excretion pathway. The results show that the maximum labeling yield (>75%) was obtained by using 30 μg of ICD-85 in phosphate buffer (60 μl, pH 7.1) at room temperature. Bio-distribution studies with radiolabeled ICD-85 shows moderate clearance of the complex from blood. The improvement of the immunotherapeutic treatment of cancer requires a better knowledge of the biological actions of the ICD-85 since tissue distribution studies are very important for clinical purpose

Estimation of Organ-Absorbed Doses in Human from Gamma Rays of 99mTc-DTPA Radiopharmaceutical, Using the Animal Dissection Data

Introduction: Scintigraphy of renal system with radiopharmaceuticals extracts provides us with essential information as to assist the diagnosis and management of patients. In this research, effective doses of human’s organs due to gamma-rays of 99mTc-DTPA are estimated using the animal dissection data.Materials and Methods: In this study, the human absorbed and effective doses from 99mTc-DTPA are obtained from animal organs data, using medical internal radiation dosimetry (MIRD) method and MCNP simulation code. In each stage, three mice were injected and sacrificed, and then their organs were dissected and counted by well detector. Results: The results of MIRD and MCNP simulation code indicated that the two mentioned methods are in agreement. Also, kidney (1.23E-03mGy/MBq), spleen (2.81E-03 mGy/MBq) and heart (2.75E-03 mGy/MBq) absorbed the most gamma dose compared to the other organs.Conclusion: According to the results and comparison with ICRP data, animal dissection model can be a useful tool for internal absorbed dose estimation of renal radiopharmaceuticals.  

131I-Chlorotoxin dosimetry in liver using MCNP simulation code

     Chlorotoxin is a 36 amino acids peptide, which is able to block chloride channels isolated from mouse brain. A derivative of chlorotoxin is synthesized and it is labeled by iodine 131; then animal experiments carry out on rats. Multiple organ doses may be calculated with biological distribution results in rats with labeled compounds using simulated MCNP4C code. Human dose can be calculated using the dose distribution in rats with a conversion ratio for dose distribution. Chloramine T is our method for marking, and electrophilic substitution reactions are methods for iodize of peptides. Simulation of a human phantom to evaluate dose distribution was done using simulation code MCNP4C. To evaluate the dose distribution in the human body, using this code and the accumulated activity in each organ tissue dose is calculated. To study the biological distribution of the radiotracer 131I, 0.37 MBq radiotracer was injected into rat via the tail vein. The accumulated activity in each organ with the agent “ID / g” is determined. Biological distribution of 131I-chlorotoxine in the normal rats is obtained. Its Decay constant in the liver is 0.07h and the effective half-life of the radiotracer is 10h in rat liver. The total number of particles found in the leak from liver tissue was reported 67600. Liver tissue dosimetries originating from other sources (thyroid tissue, stomach, kidney, right & left lung, spleen, and pancreas) were examined. Then, the overall dose to the target tissue will be calculated. Leaked beta particles in liver itself (self-dose) are the most delivered dose to the liver (98%); it is for gamma rays 1.1%, while its source is adjacent tissues in addition to liver (cross-dose); Because of low atomic number of the tissue, delivered dose originated from Bremsstrahlung (braking radiation) is low (0.9%). Radiation dose to the liver in intravenous injection of 0.37 MBq  131I-chlorotoxine radiotracer is 3.44 * 10-6.

The COVID-19 vaccination acceptance/hesitancy rate and its determinants among healthcare workers of 91 Countries: A multicenter cross-sectional study.

The aim of this study was to investigate the COVID-19 vaccination acceptance rate and its determinants among healthcare workers in a multicenter study. This was a cross-sectional multi-center survey conducted from February 5 to April 29, 2021. The questionnaire consisted of 26 items in 6 subscales. The English version of the questionnaire was translated into seven languages and distributed through Google Forms using snowball sampling; a colleague in each country was responsible for the forward and backward translation, and also the distribution of the questionnaire. A forward stepwise logistic regression was utilized to explore the variables and questionnaire factors tied to the intention to COVID-19 vaccination. 4630 participants from 91 countries completed the questionnaire. According to the United Nations Development Program 2020, 43.6 % of participants were from low Human Development Index (HDI) regions, 48.3 % high and very high, and 8.1 % from medium. The overall vaccination hesitancy rate was 37 %. Three out of six factors of the questionnaire were significantly related to intention to the vaccination. While 'Perceived benefits of the COVID-19 vaccination' (OR: 3.82, p-value<0.001) and 'Prosocial norms' (OR: 5.18, p-value<0.001) were associated with vaccination acceptance, 'The vaccine safety/cost concerns' with OR: 3.52, p-value<0.001 was tied to vaccination hesitancy. Medical doctors and pharmacists were more willing to take the vaccine in comparison to others. Importantly, HDI with OR: 12.28, 95 % CI: 6.10-24.72 was a strong positive determinant of COVID-19 vaccination acceptance. This study highlighted the vaccination hesitancy rate of 37 % in our sample among HCWs. Increasing awareness regarding vaccination benefits, confronting the misinformation, and strengthening the prosocial norms would be the primary domains for maximizing the vaccination coverage. The study also showed that the HDI is strongly associated with the vaccination acceptance/hesitancy, in a way that those living in low HDI contexts are more hesitant to receive the vaccine

An indication of anisotropy in arrival directions of utra-high-energy cosmic rays through comparison to the flux pattern of extragalactic gamma-ray sources

CNPQ - CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICOFINEP - FINANCIADORA DE ESTUDOS E PROJETOSFAPERJ - FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE RIO DE JANEIROFAPESP - FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULOMCTIC - MINISTÉRIO DA CIÊNCIA, TECNOLOGIA, INOVAÇÕES E COMUNICAÇÕESA new analysis of the data set from the Pierre Auger Observatory provides evidence for anisotropy in the arrival directions of ultra-high-energy cosmic rays on an intermediate angular scale, which is indicative of excess arrivals from strong, nearby sources. The data consist of 5514 events above 20 EeV with zenith angles up to 80 degrees. recorded before 2017 April 30. Sky models have been created for two distinct populations of extragalactic gamma-ray emitters: active galactic nuclei from the second catalog of hard Fermi-LAT sources (2FHL) and starburst galaxies from a sample that was examined with Fermi-LAT. Flux-limited samples, which include all types of galaxies from the Swift-BAT and 2MASS surveys, have been investigated for comparison. The sky model of cosmic-ray density constructed using each catalog has two free parameters, the fraction of events correlating with astrophysical objects, and an angular scale characterizing the clustering of cosmic rays around extragalactic sources. A maximum-likelihood ratio test is used to evaluate the best values of these parameters and to quantify the strength of each model by contrast with isotropy. It is found that the starburst model fits the data better than the hypothesis of isotropy with a statistical significance of 4.0 sigma, the highest value of the test statistic being for energies above 39 EeV. The three alternative models are favored against isotropy with 2.7 sigma-3.2 sigma significance. The origin of the indicated deviation from isotropy is examined and prospects for more sensitive future studies are discussed.8532110CNPQ - CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICOFINEP - FINANCIADORA DE ESTUDOS E PROJETOSFAPERJ - FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE RIO DE JANEIROFAPESP - FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULOMCTIC - MINISTÉRIO DA CIÊNCIA, TECNOLOGIA, INOVAÇÕES E COMUNICAÇÕESCNPQ - CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICOFINEP - FINANCIADORA DE ESTUDOS E PROJETOSFAPERJ - FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE RIO DE JANEIROFAPESP - FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULOMCTIC - MINISTÉRIO DA CIÊNCIA, TECNOLOGIA, INOVAÇÕES E COMUNICAÇÕESSem informaçãoSem informaçãoSem informaçãoSem informaçãoSem informaçãoAgências de fomento estrangeiras apoiaram essa pesquisa, mais informações acesse artig

Inferences on mass composition and tests of hadronic interactions from 0.3 to 100 EeV using the water-Cherenkov detectors of the Pierre Auger Observatory

CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO - CNPQFINANCIADORA DE ESTUDOS E PROJETOS - FINEPFUNDAÇÃO CARLOS CHAGAS FILHO DE AMPARO À PESQUISA DO ESTADO DO RIO DE JANEIRO - FAPERJFUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESPWe present a new method for probing the hadronic interaction models at ultrahigh energy and extracting details about mass composition. This is done using the time profiles of the signals recorded with the water-Cherenkov detectors of the Pierre Auger Observatory. The profiles arise from a mix of the muon and electromagnetic components of air showers. Using the risetimes of the recorded signals, we define a new parameter, which we use to compare our observations with predictions from simulations. We find, first, inconsistencies between our data and predictions over a greater energy range and with substantially more events than in previous studies. Second, by calibrating the new parameter with fluorescence measurements from observations made at the Auger Observatory, we can infer the depth of shower maximum X-max for a sample of over 81,000 events extending from 0.3 to over 100 EeV. Above 30 EeV, the sample is nearly 14 times larger than what is currently available from fluorescence measurements and extending the covered energy range by half a decade. The energy dependence of < X-max gt; is compared to simulations and interpreted in terms of the mean of the logarithmic mass. We find good agreement with previous work and extend the measurement of the mean depth of shower maximum to greater energies than before, reducing significantly the statistical uncertainty associated with the inferences about mass composition.9612122CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO - CNPQFINANCIADORA DE ESTUDOS E PROJETOS - FINEPFUNDAÇÃO CARLOS CHAGAS FILHO DE AMPARO À PESQUISA DO ESTADO DO RIO DE JANEIRO - FAPERJFUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESPCONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO - CNPQFINANCIADORA DE ESTUDOS E PROJETOS - FINEPFUNDAÇÃO CARLOS CHAGAS FILHO DE AMPARO À PESQUISA DO ESTADO DO RIO DE JANEIRO - FAPERJFUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESPSem informaçãoSem informaçãoSem informação1999/05404-32010/07359-6The successful installation, commissioning, and operation of the Pierre Auger Observatory would not have been possible without the strong commitment and effort from the technical and administrative staff in Malargue. We are very grateful to the following agencies and organizations for financial support: (Argentina) Comision Nacional de Energia Atomica; Agencia Nacional de Promocion Cientifica y Tecnologica (ANPCyT); Consejo Nacional de Investigaciones Cientificas y Tecnicas (CONICET); Gobierno de la Provincia de Mendoza; Municipalidad de Malargue; and NDM Holdings and Valle Las Lenas in gratitude for their continuing cooperation over land access; (Australia) the Australian Research Council; (Brazil) Conselho Nacional de Desenvolvimento Cientifico e Tecnologico (CNPq); Financiadora de Estudos e Projetos (FINEP); Fundacao de Amparo a Pesquisa do Estado de Rio de Janeiro (FAPERJ); Sao Paulo Research Foundation (FAPESP) Grants No. 2010/07359-6 and No. 1999/05404-3; Ministerio de Ciencia e Tecnologia (MCT); (Czech Republic) Grants No. MSMT CR LG15014, LO1305, LM2015038, and CZ.02.1.01/0.0/0.0/16\_013/0001402; (France) Centre de Calcul IN2P3/CNRS; Centre National de la Recherche Scientifique (CNRS); Conseil Regional Ile-de-France; Departement Physique Nucleaire et Corpusculaire (PNC-IN2P3/CNRS); Departement Sciences de l'Univers (SDU-INSU/CNRS); Institut Lagrange de Paris (ILP) Grant No. LABEX ANR-10-LABX-63 within the Investissements d'Avenir Programme Grant No. ANR-11-IDEX-0004-02; (Germany) Bundesministerium fur Bildung und Forschung (BMBF); Deutsche Forschungsgemeinschaft (DFG); Finanzministerium Baden-Wurttemberg; Helmholtz Alliance for Astroparticle Physics (HAP); Helmholtz-Gemeinschaft Deutscher Forschungszentren (HGF); Ministerium fur Innovation, Wissenschaft und Forschung des Landes Nordrhein-Westfalen; Ministerium fur Wissenschaft, Forschung und Kunst des Landes Baden-Wurttemberg; (Italy) Istituto Nazionale di Fisica Nucleare (INFN); Istituto Nazionale di Astrofisica (INAF); Ministero dell'Istruzione, dell'Universita e della Ricerca (MIUR); CETEMPS Center of Excellence; Ministero degli Affari Esteri (MAE); (Mexico) Consejo Nacional de Ciencia y Tecnologia (CONACYT) Grant No. 167733; Universidad Nacional Autonoma de Mexico (UNAM); PAPIIT DGAPA-UNAM; (Netherlands) Ministerie van Onderwijs, Cultuur en Wetenschap; Nederlandse Organisatie voor Wetenschappelijk Onderzoek (NWO); Stichting voor Fundamenteel Onderzoek der Materie (FOM); (Poland) National Centre for Research and Development, Grants No. ERA-NET-ASPERA/01/11 and No. ERA-NET-ASPERA/02/11; National Science Centre, Grants No. 2013/08/M/ST9/00322, No. 2013/08/M/ST9/00728, No. HARMONIA 5-2013/10/M/ST9/00062, and No. UMO-2016/22/M/ST9/00198; (Portugal) Portuguese national funds and FEDER funds within Programa Operacional Factores de Competitividade through Fundacao para a Ciencia e a Tecnologia (COMPETE); (Romania) Romanian Authority for Scientific Research ANCS; CNDI-UEFISCDI partnership projects Grants No. 20/2012, No. 194/2012, and No. PN 16 42 01 02; (Slovenia) Slovenian Research Agency; (Spain) Comunidad de Madrid; Fondo Europeo de Desarrollo Regional (FEDER) funds; Ministerio de Economia y Competitividad; Xunta de Galicia; European Community 7th Framework Program Grant No. FP7-PEOPLE-2012-IEF-328826; (USA) Department of Energy, Contracts No. DE-AC02-07CH11359, No. DE-FR02-04ER41300, No. DE-FG02-99ER41107, and No. DE-SC0011689; National Science Foundation, Grant No. 0450696; The Grainger Foundation; Marie Curie-IRSES/EPLANET (European Union); European Particle Physics Latin American Network; European Union 7th Framework Program, Grant No. PIRSES-2009-GA-246806; European Union's Horizon 2020 Research and Innovation Programme (Grant No. 646623); and UNESCO

Depth Of Maximum Of Air-shower Profiles At The Pierre Auger Observatory. I. Measurements At Energies Above 1017.8ev

901

A modified PSO with fuzzy inference system for solving the planar graph coloring problem

There are several optimization problems with number of feasible solution is polynomial bounded by the size of the given input instances. Graph Coloring is a classic NP-hard problem; hence, it is theoretically of great importance. Diverse applications of Graph Coloring have made the scientific community to be constantly searching for elegant solutions. Some of these applications are communication network, mobile radio frequency, computer register allocation, printed circuit board testing, time tabling and scheduling, pattern matching and Sudoku games. Many solutions have been proposed by the previous studies on solving Graph Coloring problems. But the most recent and efficient approach is commonly based on hybrid algorithms that use a particular kind of recombination operator. Hence, this study proposes a modified particle swarm optimization with fuzzy logic to obtain a high performance algorithm for solving the Planar Graph Coloring problem. Experimental results on several randomly generated graphs have illustrated the efficiency of the proposed method accordingly

Evaluation of a new bombesin analogue labeled with 99mTc as potential targeted tumor scintigraphic agent

Background: Bombesin shows high affinity for Gastrin-releasing peptide (GRP) receptors which over expressed on the cell surfaces of several human tumors particularly in prostate and breast cancers. The aim of this study was labeling of designed analogue with99mTc via HYNIC and Tricine /EDDA and evaluation as potential targeted tumor scintigraphic agent.Materials and Methods: HYNIC-Bombesin was prepared by solid phase synthesis using Fmoc strategy and radiolabeled with 99mTc at 100 °C for 10 min by exchange method and radiochemical analysis involved ITLC and HPLC methods. The stability of radiopeptide was checked in the presence of human serum at 37 °C up to 24 h. Internalization was studied with the human GRP receptor cell line PC-3. Biodistribution study was performed in mice. Results: Radiochemical purities of >98% was obtained. Radiopeptide showed high stability in serum. Radioligand internalization into PC-3 cells was high and specific. Biodistribution study demonstrated that 99mTc-HYNIC peptide cleared fast from blood and most non-targeted tissues and was excreted mainly by renal pathway and was uptake significantly in GRPr positive tissues such as pancreas. Conclusion: Easy radiolabeling of peptide conjugate together with favorable in vitro and in vivo characteristics might be a useful peptide radiopharmaceutical in diagnosis of GRPr positive tumors