60 results match your criteria: "Nuclear and Energy Research Institute - IPEN-CNEN[Affiliation]"
Chem Rev
February 2022
Nuclear and Energy Research Institute (IPEN-CNEN), Av. Lineu Prestes, 2242, 05508-000 São Paulo, SP, Brazil.
Direct conversion of methane to C compounds by oxidative and nonoxidative coupling reactions has been intensively studied in the past four decades; however, because these reactions have intrinsic severe thermodynamic constraints, they have not become viable industrially. Recently, with the increasing availability of inexpensive "green electrons" coming from renewable sources, electrochemical technologies are gaining momentum for reactions that have been challenging for more conventional catalysis. Using solid-state membranes to control the reacting species and separate products in a single step is a crucial advantage.
View Article and Find Full Text PDFJ Biomater Sci Polym Ed
April 2022
Nuclear and Energy Research Institute - IPEN-CNEN, São Paulo, Brazil.
Polymeric nanoparticles acting as sources of selenium (Se) are currently an interesting topic in cancer chemotherapy. In this study, polyglycerol dendrimer (DPGLy) was functionalized with seleno-methyl-selenocysteine (SeMeCys) by means of Steglich esterification with 4-dimethylaminopyridine/(l-ethyl-3-(3-dimethylaminopropyl)carbodiimide) (EDC/DMAP) and cerium chloride as cocatalyst in acetonitrile at quantitative yields of 98 ± 1%. The SeMeCys coupling DPGLy efficiency vs.
View Article and Find Full Text PDFJ Photochem Photobiol B
July 2021
Center for Lasers and Applications, Nuclear and Energy Research Institute (IPEN/ CNEN), Av. Prof. Lineu Prestes, 2242, 05508-000, Brazil. Electronic address:
This work investigated the effect of photobiomodulation therapy (PBM) combined with radiotherapy (RT) on triple-negative breast cancer (TNBC)-bearing mice. Female BALB/c mice received 4 T1 cells into a mammary fat pad. Local RT was performed with a total dose of 60 Gy divided into 4 consecutive sessions of 15 Gy.
View Article and Find Full Text PDFBioorg Chem
August 2021
School of Pharmaceutical Sciences of Ribeirão Preto, University of São Paulo, Ribeirão Preto, São Paulo, Brazil. Electronic address:
ERK1/2 inhibitors have attracted special attention concerning the ability of circumventing cases of innate or log-term acquired resistance to RAF and MEK kinase inhibitors. Based on the 4-aminoquinazoline pharmacophore of kinases, herein we describe the synthesis of 4-aminoquinazoline derivatives bearing a 1,2,3-triazole stable core to bridge different aromatic and heterocyclic rings using copper-catalysed azide-alkyne cycloaddition reaction (CuAAC) as a Click Chemistry strategy. The initial screening of twelve derivatives in tumoral cells (CAL-27, HN13, HGC-27, and BT-20) revealed that the most active in BT-20 cells (25a, IC 24.
View Article and Find Full Text PDFJ Venom Anim Toxins Incl Trop Dis
April 2021
Laboratory of Protozoology, Institute of Tropical Medicine, University of São Paulo (IMT/FMUSP), São Paulo, SP, Brazil.
Background: Tetanus toxin blocks the release of the inhibitory neurotransmitters in the central nervous system and causes tetanus and its main form of prevention is through vaccination. The vaccine is produced by inactivation of tetanus toxin with formaldehyde, which may cause side effects. An alternative way is the use of ionizing radiation for inactivation of the toxin and also to improve the potential immunogenic response and to reduce the post-vaccination side effects.
View Article and Find Full Text PDFBull Environ Contam Toxicol
July 2021
São Paulo Adventist University (UNA SP), Estrada Municipal Pastor Walter Boger, s/n, Engenheiro Coelho, SP, 13445-970, Brazil.
The control of air pollution remains a challenge to the planning of cities and fossil fuel burning is the main cause of air degradation. Particulate matter (PM) is the contaminant commonly used as an indicator of pollution, but environmental agencies may face difficulties in operating surveillance networks due to the lack of resources and infrastructure. As an alternative to conventional networks, scientific studies have pointed out that nature itself can contribute to the diagnosis and reduction of air pollution.
View Article and Find Full Text PDFAnn Nucl Med
February 2021
Division of Nuclear Medicine of the Department of Radiology, University of Campinas (UNICAMP), Campinas, Brazil.
Introduction: Radiosynovectomy (RS) with Y-hydroxyapatite (Y-HyA) aims to control knee hemarthrosis in hemophiliac patients to prevent secondary arthropathy. However, knee RS using Sm-hydroxyapatite (Sm-HyA) is considered less suitable due to the lower average soft tissue range and energy of Sm for large joints, such as the knees.
Purpose: The objective of this investigation was to assess the efficacy and safety of knee RS with Sm-HyA, compared to Y-HyA.
Acta Trop
March 2021
Nuclear and Energy Research Institute-IPEN-CNEN/SP, Av. Professor Lineu Prestes, 2242, - Cidade Universitária CEP 05508-000, São Paulo-SP, Brazil.
Amphotericin B (Amph-B) is an antifungal drug used intravenously for the treatment of leishmaniasis. Side-effects from Amph-B treatment can arise such as cardiac arrhythmia and renal dysfunctions, which will lead to discontinuation of treatment. Unfortunately, patients in endemic countries do not have access to alternative therapies.
View Article and Find Full Text PDFMicrosc Res Tech
March 2021
Nuclear and Energy Research Institute (IPEN-CNEN/SP), Center for Lasers and Applications, São Paulo, SP, Brazil.
Laminate veneer removal is becoming a routine procedure at the dental clinic and the use of laser can facilitate its removal. This work aimed to evaluate the morphological, elemental, and optical changes in the remaining enamel after veneer removal using Er,Cr:YSGG laser. Forty-four enamel slabs were prepared and randomly distributed into nine experimental groups, for bonding using lithium disilicate laminates with three different luting agents (Variolink Veneer, RelyX U200, and RelyX Veneer).
View Article and Find Full Text PDFPhotodiagnosis Photodyn Ther
December 2020
Center for Lasers and Applications, Nuclear and Energy Research Institute (IPEN-CNEN/SP), São Paulo, SP, Brazil. Electronic address:
Cell Tissue Bank
March 2024
Interunit Graduate Program in Bioengineering, University of São Paulo, São Carlos, SP, Brazil.
The aim of this study was the development of collagen and collagen/auricular cartilage scaffolds for application in dermal regeneration. Collagen was obtained from bovine tendon by a 72 h-long treatment, while bovine auricular cartilage was treated for 24 h and divided into two parts, external (perichondrium, E) and internal (elastic cartilage, I). The scaffolds were prepared by mixing collagen (C) with the internal part (CI) or the external part (CE) in a 3:1 ratio.
View Article and Find Full Text PDFJ Contemp Dent Pract
March 2020
Department of Physics, School of Dentistry, Federal University of Pernambuco (UFPE), Recife-PE, Brazil, Phone: +55 8121268000, e-mail:
Aim: To compare the effect of erbium, chromium:yttrium-scandium-gallium-garnet (Er,Cr:YSGG) laser at different irradiation parameters and acid etching on the shear bond strength (SBS) of orthodontic brackets to enamel.
Materials And Methods: Forty bovine incisors were randomly distributed into groups ( = 10): GI: 37% phosphoric acid etching; GII: Er,Cr:YSGG laser etching 19.1 J/cm; GIII: Er,Cr:YSGG, 29.
Molecules
April 2020
Radiopharmacy Center, Nuclear and Energy Research Institute (IPEN/CNEN-SP), CEP 05508-000 São Paulo, Brazil.
Losartan is widely used in clinics to treat cardiovascular related diseases by selectively blocking the angiotensin II type 1 receptors (ATRs), which regulate the renin-angiotensin system (RAS). Therefore, monitoring the physiological and pathological biodistribution of ATR using positron emission tomography (PET) might be a valuable tool to assess the functionality of RAS. Herein, we describe the synthesis and characterization of two novel losartan derivatives PET tracers, [F]fluoroethyl-losartan ([F]FEtLos) and [F]ammoniomethyltrifluoroborate-losartan ([F]AMBFLos).
View Article and Find Full Text PDFMolecules
February 2020
Albert Einstein Research and Education Institute, Hospital Israelita Albert Einstein, São Paulo 05652-900, Brazil.
Natural triterpenes exhibit a wide range of biological activities. Since this group of secondary metabolites is structurally diverse, effects may vary due to distinct biochemical interactions within biological systems. In this work, we investigated the anticancer-related activities of the quinone-methide triterpene maytenin and its derivative compound 22-β-hydroxymaytenin, obtained from roots cultivated in vitro.
View Article and Find Full Text PDFJ Dent
January 2020
Department of Restorative Dentistry, University of São Paulo, School of Dentistry, Av. Prof. Lineu Prestes 2227, São Paulo, SP, 05508-000, Brazil. Electronic address:
Objective: To evaluate the anti-erosive effect of solutions containing β-tricalcium phosphate (β-TCP) nanoparticles functionalized with fluoride or with fluoride plus stannous on enamel and dentin.
Methods: β-TCP nanoparticles were synthesized and characterized by X-ray diffraction (XRD) and transmission electron microscopy (TEM). Sixty enamel and dentin specimens were randomly allocated into the groups (n = 10): Control (water); F (NaF, 225 ppm F); F + Sn (NaF + SnCl 800 ppm Sn); F+β-TCP (F+40 ppm β-TCP); F + Sn+β-TCP (F + Sn+40 ppm β-TCP); F + Sn+100β-TCP (F + Sn+100 ppm β-TCP).
Photochem Photobiol
May 2020
Center for Lasers and Applications, Nuclear and Energy Research Institute (IPEN-CNEN/SP), São Paulo, SP, Brazil.
Cutaneous leishmaniasis (CL) is a neglected disease that promotes destructive lesions. Difficulties in treatment are related to accessibility of drugs, resistance and toxicity. Antimicrobial photodynamic therapy (APDT) has been emerging as a promising treatment for CL.
View Article and Find Full Text PDFAppl Radiat Isot
January 2020
Ankara University, Institute of Nuclear Sciences, Ankara, Turkey.
Nitric Oxide
December 2019
Center for Lasers and Applications, Nuclear and Energy Research Institute (IPEN-CNEN/SP), Av. Prof. Lineu Prestes, 2242, CEP 05508-000, São Paulo, SP, Brazil. Electronic address:
Leishmaniasis is a neglected tropical disease that demands for new therapeutic strategies due to adverse side effects and resistance development promoted by current drugs. Nitric oxide (NO)-donors show potential to kill Leishmania spp. but their use is limited because of their instability.
View Article and Find Full Text PDFSci Rep
June 2019
Department of Electrical Engineering and Computer Science, Research Laboratory of Electronics, Massachusetts Institute of Technology, Cambridge, Massachusetts, USA.
The recent clinical adoption of optical coherence tomography (OCT) angiography (OCTA) has enabled non-invasive, volumetric visualization of ocular vasculature at micron-scale resolutions. Initially limited to 3 mm × 3 mm and 6 mm × 6 mm fields-of-view (FOV), commercial OCTA systems now offer 12 mm × 12 mm, or larger, imaging fields. While larger FOVs promise a more complete visualization of retinal disease, they also introduce new challenges to the accurate and reliable interpretation of OCTA data.
View Article and Find Full Text PDFChemphyschem
August 2019
Department of Fundamental Chemistry Institute of Chemistry, University of São Paulo, Av. Prof. Lineu Prestes, São Paulo-SP, 05508-000, Brazil.
Arch Oral Biol
March 2019
Special Laboratory of Lasers in Dentistry (LELO), Department of Restorative Dentistry, School of Dentistry, University of São Paulo, Av. Prof. Lineu Prestes 2227, São Paulo, SP, 05508-000. Electronic address:
Objective: To evaluate the effect of Er,Cr:YSGG laser associated or not with acidulated phosphate fluoride (APF) on the control of enamel erosion progression.
Design: Enamel slabs (4 mm × 4 mm × 2 mm) from bovine incisors were flattened, polished, and received a tape on their test surfaces, leaving a 4 mm × 1 mm area exposed. Specimens were eroded (10 min in 1% citric acid solution) and randomly assigned into 8 experimental groups (n = 10): Control (no treatment); F (APF gel, 1.
Retina
March 2020
Department of Ophthalmology, New England Eye Center, Tufts Medical Center, Boston, Massachusetts.
Purpose: To combine advances in high-speed, wide-field optical coherence tomography angiography (OCTA) with image processing methods for semiautomatic quantitative analysis of capillary nonperfusion in patients with diabetic retinopathy (DR).
Methods: Sixty-eight diabetic patients (73 eyes), either without retinopathy or with different degrees of retinopathy, were prospectively recruited for volumetric swept-source OCTA imaging using 12 mm × 12 mm fields centered at the fovea. A custom, semiautomatic software algorithm was used to quantify areas of capillary nonperfusion.
J Microencapsul
May 2018
c Department of Organic Chemistry, Institute of Chemistry, UNICAMP SP , São Paulo , Brazil.
Biodegradable polymers containing radioactive isotopes such as Holmium 166 (Ho) have potential applications as beta particle emitters in tumour tissues. It is also a gamma ray emitter, allowing nuclear imaging of any tissue to be acquired. It is frequently used in the form of complexes such as holmium acetylacetonate (HoAcAc), which may cause damages in tissues next to the targets cancer cells, as it is difficult to control its linkage or healthy tissues radiotherapy effects.
View Article and Find Full Text PDFJ Radioanal Nucl Chem
October 2017
Chemical Sciences Division, National Institute of Standards and Technology, 100 Bureau Drive, MS 8395, Gaithersburg, MD 20899-8395, USA.
A new γγ coincidence system has been set up at NIST. It is operated with a digital data finder supported by new software developed at NIST. The system is used to explore possible enhancements in instrumental neutron activation analysis (INAA) and study applicability to neutron capture prompt gamma activation analysis (PGAA).
View Article and Find Full Text PDFPhysiol Behav
February 2017
Neuroimmunomodulation Research Group, School of Veterinary Medicine and Animal Science, University of São Paulo, São Paulo, Brazil; Department of Pathology, School of Veterinary Medicine, Universidade de São Paulo, São Paulo, SP, Brazil. Electronic address:
Cohabitation with Ehrlich ascitic tumor-injected conspecifics induces behavioral, neurochemical, endocrine and immune changes indicative of stress and immune impairment in female mice. The present work analyzed the effects of similar cohabitation in Swiss and Balb/C male mice. At least 12 pairs of male mice were divided into a control group and an experimental group.
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