Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 20
Filter
1.
Braz J Med Biol Res ; 57: e13250, 2024.
Article in English | MEDLINE | ID: mdl-38808886

ABSTRACT

Apurinic/apyrimidinic endonuclease 1/redox factor-1 (APE1/REF-1) is a multifunctional protein acting on cellular signaling pathways, including DNA repair and redox activities. APE1/REF-1 has emerged as a target for cancer therapy, and its role in breast cancer models would reveal new strategies for cancer therapy. APX2009 is a specific APE1/REF-1 redox inhibitor whose anticancer properties have not been described in breast cancer cells. Here, we investigated the effect of the APX2009 treatment in the breast cancer cell lines MDA-MB-231 and MCF-7. Breast cancer cell lines were cultured, and WST1 and colony formation assays were performed to evaluate cell proliferation. Annexin V-FITC/7-AAD and LDH-Glo™ assays were performed to evaluate cell death. The wound healing assay and Matrigel transwell assay were performed after APX2009 treatment to evaluate the cellular migration and invasion processes, respectively. Our findings demonstrated that APX2009 treatment decreased breast cancer cell proliferative, migratory, and invasive properties. Furthermore, it induced apoptosis in both cell lines. Our study is the first to show the effects of APX2009 treatment on apoptosis in a breast cancer cell. Therefore, this study suggested that APX2009 treatment is a promising anticancer molecule for breast cancer.


Subject(s)
Apoptosis , Breast Neoplasms , Cell Movement , Cell Proliferation , DNA-(Apurinic or Apyrimidinic Site) Lyase , Oxidation-Reduction , Humans , Breast Neoplasms/pathology , Breast Neoplasms/drug therapy , Breast Neoplasms/metabolism , DNA-(Apurinic or Apyrimidinic Site) Lyase/metabolism , DNA-(Apurinic or Apyrimidinic Site) Lyase/antagonists & inhibitors , Cell Proliferation/drug effects , Female , Cell Movement/drug effects , Cell Line, Tumor , Apoptosis/drug effects , Oxidation-Reduction/drug effects , Phenotype , MCF-7 Cells , Antineoplastic Agents/pharmacology
2.
Sci Rep ; 14(1): 9868, 2024 Apr 29.
Article in English | MEDLINE | ID: mdl-38684890

ABSTRACT

This comprehensive study delves into the intricate interplay between protons and organic polymers, offering insights into proton therapy in cancer treatment. Focusing on the influence of the spatial electron density distribution on stopping power estimates, we employed real-time time-dependent density functional theory coupled with the Penn method. Surprisingly, the assumption of electron density homogeneity in polymers is fundamentally flawed, resulting in an overestimation of stopping power values at energies below 2 MeV. Moreover, the Bragg rule application in specific compounds exhibited significant deviations from experimental data around the stopping maximum, challenging established norms.

3.
Braz. j. med. biol. res ; 57: e13250, fev.2024. graf
Article in English | LILACS-Express | LILACS | ID: biblio-1557307

ABSTRACT

Apurinic/apyrimidinic endonuclease 1/redox factor-1 (APE1/REF-1) is a multifunctional protein acting on cellular signaling pathways, including DNA repair and redox activities. APE1/REF-1 has emerged as a target for cancer therapy, and its role in breast cancer models would reveal new strategies for cancer therapy. APX2009 is a specific APE1/REF-1 redox inhibitor whose anticancer properties have not been described in breast cancer cells. Here, we investigated the effect of the APX2009 treatment in the breast cancer cell lines MDA-MB-231 and MCF-7. Breast cancer cell lines were cultured, and WST1 and colony formation assays were performed to evaluate cell proliferation. Annexin V-FITC/7-AAD and LDH-Glo™ assays were performed to evaluate cell death. The wound healing assay and Matrigel transwell assay were performed after APX2009 treatment to evaluate the cellular migration and invasion processes, respectively. Our findings demonstrated that APX2009 treatment decreased breast cancer cell proliferative, migratory, and invasive properties. Furthermore, it induced apoptosis in both cell lines. Our study is the first to show the effects of APX2009 treatment on apoptosis in a breast cancer cell. Therefore, this study suggested that APX2009 treatment is a promising anticancer molecule for breast cancer.

4.
Earth Space Sci ; 8(1): e2020EA001363, 2021 Jan.
Article in English | MEDLINE | ID: mdl-33681415

ABSTRACT

Synthetic Aperture Radar (SAR) data are well-suited for change detection over agricultural fields, owing to high spatiotemporal resolution and sensitivity to soil and vegetation. The goal of this work is to evaluate the science algorithm for the NASA ISRO SAR (NISAR) Cropland Area product using data collected by NASA's airborne Uninhabited Aerial Vehicle SAR (UAVSAR) platform and the simulated NISAR data derived from it. This study uses mode 129, which is to be used for global-scale mapping. The mode consists of an upper (129A) and lower band (129B), respectively having bandwidths of 20 and 5 MHz. This work uses 129A data because it has a four times finer range resolution compared to 129B. The NISAR algorithm uses the coefficient of variation (CV) to perform crop/noncrop classification at 100 m. We evaluate classifications using three accuracy metrics (overall accuracy, J-statistic, Cohen's Kappa) and spatial resolutions (10, 30, and 100 m) for crop/noncrop delineating CV thresholds (CVthr) ranging from 0 to 1 in 0.01 increments. All but the 10 m 129A product exceeded NISAR's mission accuracy requirement of 80%. The UAVSAR 10 m data performed best, achieving maximum overall accuracy, J-statistic, and Kappa values of 85%, 0.62, and 0.60. The same metrics for the 129A product respectively are: 77%, 0.40, 0.36 at 10 m; 81%, 0.55, 0.49 at 30 m; 80%, 0.58, 0.50 at 100 m. We found that using a literature recommended CVthr value of 0.5 yielded suboptimal accuracy (65%) at this site and that optimal CVthr values monotonically decreased with decreasing spatial resolution.

5.
Surv Geophys ; 40(4): 979-999, 2019.
Article in English | MEDLINE | ID: mdl-31395994

ABSTRACT

Several upcoming satellite missions have core science requirements to produce data for accurate forest aboveground biomass mapping. Largely because of these mission datasets, the number of available biomass products is expected to greatly increase over the coming decade. Despite the recognized importance of biomass mapping for a wide range of science, policy and management applications, there remains no community accepted standard for satellite-based biomass map validation. The Committee on Earth Observing Satellites (CEOS) is developing a protocol to fill this need in advance of the next generation of biomass-relevant satellites, and this paper presents a review of biomass validation practices from a CEOS perspective. We outline the wide range of anticipated user requirements for product accuracy assessment and provide recommendations for the validation of biomass products. These recommendations include the collection of new, high-quality in situ data and the use of airborne lidar biomass maps as tools toward transparent multi-resolution validation. Adoption of community-vetted validation standards and practices will facilitate the uptake of the next generation of biomass products.

6.
Pak J Biol Sci ; 10(4): 568-74, 2007 Feb 15.
Article in English | MEDLINE | ID: mdl-19069536

ABSTRACT

The present research evaluated the influence of a chayotte (Sechium edule) extract (macerated) on the bioavailability of 99TcO4Na as well as in the mass of the organs. In this study, in the biodistribution analysis, the 99mTcO4Na was administrated into female Wistar rats (diabetes and no diabetes induced) which had drunk or not the extract for 7 days. After 10 min, animals were sacrificed, the organs were isolated, the radioactivity determined in a well counter and the percentages of radioactivity per gram (%ATI/g) in the organs and mass of them (g) were calculated. The analysis of the results has indicated that in the diabetes group had been an increase in the uptake of 99mTcO4Na the in pancreas as well as in the diabetes groups treated with chayotte extract. The mass of the spleen, stomach, pancreas, heart and kidney has been altered due to the comparison of the groups. It is possible to suggest that some components of chayotte extracts present an oxidant power able to alter the biodistribution of 99mTcO4Na, as a tip, we speculate that the referred extract when metabolized in the liver may produce reactive metabolites with oxidant properties linked to the stress which is generated by diabetic status, this fact could justify by the increase of %ATI/g in the pancreas which probably may be due to the producing of AGEs in diabetes status as well as by the different molecular and cellular mechanisms related to the effects of the extract and diabetes would promote differences in the mass of the organs.


Subject(s)
Cucurbitaceae/chemistry , Diabetes Mellitus, Experimental/drug therapy , Diabetes Mellitus, Experimental/radiotherapy , Plant Extracts/chemistry , Plant Extracts/therapeutic use , Radiopharmaceuticals/therapeutic use , Animals , Diabetes Mellitus, Experimental/chemically induced , Organ Size/drug effects , Plant Extracts/pharmacokinetics , Radiopharmaceuticals/pharmacokinetics , Rats , Rats, Wistar
7.
Pak J Biol Sci ; 10(5): 823-7, 2007 Mar 01.
Article in English | MEDLINE | ID: mdl-19069873

ABSTRACT

The use of natural products as medicines has been growing in the entire world. There are concerns that these products may contain potentially toxic ingredients and contaminants such as heavy metals. The labeling of blood constituents with technetium-99m has been influenced by the presence of natural extracts. We evaluated the influence of a chayotte (Sechium edule) extract (100% v/v macerated) on the labeling of blood elements with 99mTc. The animals were treated with the extract during 15 days. Samples of blood were carried out with specific blood biochemistry kits. The present study analyzed the influence ofchayotte in the survival of the strain of Escherichia coli AB1157 submitted to reactive oxygen species induced by stannous chloride. There was a reduction of the lethal effect induced by stannous chloride on the survival of the E. coli culture in the presence of chayotte. The results indicated a decrease in the level of glucose and globulin The effect of the extract could be explained by its metabolic transformation inducing the generation of oxidant metabolites. The culture of bacteria when was treated with stannous chloride and chayotte simultaneously, the extract could be reacting with stannous chloride ions, protecting them against the oxidation avoiding the generation of reactive oxygen species.


Subject(s)
Blood Chemical Analysis , Cucurbitaceae/chemistry , Plant Extracts/pharmacology , Tin Compounds/pharmacology , Animals , Rats , Rats, Wistar
9.
Rev. bras. otorrinolaringol ; 68(2): 284-286, mar.-abr. 2002.
Article in Portuguese | LILACS | ID: lil-338752

ABSTRACT

Os autores relatam um caso de Síndrome de Bernard-Soulier atendido na unidade de emergência do Hospital das Clínicas da Faculdade de Medicina da Universidade Federal de Goiás com manifestaçöes nasais, orais e gastrintestinais. Discutem consideraçöes sobre o quadro clínico, diagnóstico, tratamento e evoluçäo da doença. Alertam sobre a importância de considerar a possibilidade de discrasias sangüíneas quando frente a epistaxes de repetiçäo e/ ou de difícil tratamento

10.
J Med Microbiol ; 48(3): 303-307, 1999 Mar.
Article in English | MEDLINE | ID: mdl-10334598

ABSTRACT

Mupirocin is a topical antimicrobial agent that has been successfully used to eradicate methicillin-resistant Staphylococcus aureus from the anterior nares and other sites of patients and health care personnel. This report describes the acquisition of a novel mupirocin resistance gene (ileS) by an epidemic MRSA clone that is geographically widespread in Brazil.


Subject(s)
Anti-Bacterial Agents/pharmacology , Drug Resistance, Microbial/genetics , Mupirocin/pharmacology , Staphylococcal Infections/microbiology , Staphylococcus aureus/drug effects , Brazil , Cross Infection/microbiology , DNA, Bacterial/analysis , Disease Outbreaks , Drug Resistance, Multiple , Humans , Methicillin Resistance , Microbial Sensitivity Tests , Physical Chromosome Mapping , Staphylococcus aureus/genetics , Staphylococcus aureus/isolation & purification
11.
Braz J Med Biol Res ; 25(8): 805-7, 1992.
Article in English | MEDLINE | ID: mdl-1342612

ABSTRACT

GM1 ganglioside has been identified as the receptor for cholera toxin (CT) and heat-labile (LT) enterotoxin of Escherichia coli in many cell types. Using the radial immune hemolysis (RIH) and indirect hemagglutination (IH) tests described for the detection of these enterotoxins, a study was conducted on the 100% inhibition of these reactions by pre-incubating these enterotoxins with GM1, GD1a and GT1 gangliosides. GM1 was found to be much more efficient than the other two. With respect to the RIH test, GT1 was more efficient than GD1a as an inhibitor of enterotoxin binding. Similar results were obtained with the IH test. These data also showed that sheep red blood cells provide a good model system for the study of receptors for CT, LT and probably other enterotoxins which bind to gangliosides.


Subject(s)
Cholera Toxin/antagonists & inhibitors , Enterotoxins/antagonists & inhibitors , Escherichia coli , Gangliosides/pharmacology , Guanylate Cyclase , Animals , Cholera Toxin/immunology , Depression, Chemical , Drug Stability , Enterotoxins/immunology , Erythrocytes/drug effects , Erythrocytes/immunology , Hemagglutination Tests , Hemolytic Plaque Technique , Hot Temperature , Humans , Receptors, Enterotoxin , Receptors, Guanylate Cyclase-Coupled , Receptors, Peptide/drug effects , Receptors, Peptide/immunology , Sheep , Swine
12.
Braz. j. med. biol. res ; 25(8): 805-7, 1992. tab
Article in English | LILACS | ID: lil-113572

ABSTRACT

GM1 ganglioside has been identified as the receptor for cholera toxin (CT) and heat-labile (LT) enterotoxin of Escherichia coli in many cell types. Using the radial immune hemolysis (RIH) and indirect hemagglutination (IH) tests described for the detection of these enterotoxins, a study was conducted on the 100% inhibition of these reactions by pre-incubating these enterotoxins, a study was conducted on the 100% inhibition of these reactions by pre-incubating these enterotoxins with GM1, GD 1a and GT1 gangliosides. GM1 was found to be much more efficient than the othjer two. With respect to the RIH test, GT1 was more efficient than GD1a as an inhibitor of enterotoxin binding. Similar results were obtained with the IH test. These data also showed that sheep red blood cells provide a good model system for the study of receptors for CT, LT and probably other enterotoxins which bind to gangliosides


Subject(s)
Cholera Toxin , Enterotoxins , Escherichia coli/pathogenicity , Gangliosides/adverse effects , Hemagglutination , Hemolysis
13.
Res Microbiol ; 140(6): 393-404, 1989.
Article in English | MEDLINE | ID: mdl-2559437

ABSTRACT

Many serological reactions using red blood cells (RBC) such as radial immune haemolysis (RIH) and indirect haemagglutination (IH) tests have often been used for the detection of cholera toxin (CT) and heat-labile (LT) enterotoxin produced by porcine and human Escherichia coli strains. In these tests, the enterotoxins bind to sheep, bovine and guinea-pig RBC without any ligand. We studied several factors which might interfere with such binding, as well as the nature of the receptors involved. Treatment of erythrocytes with different enzymes revealed that proteolytic enzymes had no effect on the adsorption of enterotoxins to RBC. Conversely, treatment with neuraminidase increased the adsorption. Experiments carried out with delipidized RBC revealed that none of the enterotoxins under study bound to the cells thus treated. Pre-incubation of ganglioside fractions with the enterotoxins blocked RIH and IH reactions and the biological effect of them on Vero cells. Assaying RBC ganglioside fractions by thin-layer chromatography revealed the presence of GM1. Our results suggest that the receptors for GT and LT enterotoxins in sheep, bovine and guinea pig RBC are gangliosides: mainly GM1.


Subject(s)
Cholera Toxin/pharmacokinetics , Erythrocytes/metabolism , Guanylate Cyclase , Receptors, Cell Surface/metabolism , Receptors, Immunologic/metabolism , Receptors, Peptide , Absorption , Animals , Erythrocytes/analysis , Erythrocytes/enzymology , G(M1) Ganglioside/analysis , G(M1) Ganglioside/pharmacokinetics , Humans , Receptors, Enterotoxin , Receptors, Guanylate Cyclase-Coupled , Swine
14.
Rev Esc Enferm USP ; 23(2): 115-25, 1989 Apr.
Article in Portuguese | MEDLINE | ID: mdl-2485553

ABSTRACT

This article is a review of literature related to what motivates nursing graduates to attend freely a laboratory to better develop practical skills. It concluded that the literature indicates conditions that stimulate or discourage training of practical skills. These conditions are related to the professor, to techniques or procedures, to laboratory conditions, to evaluating systems and to the student himself.


Subject(s)
Education, Nursing , Laboratories , Teaching/methods , Humans , Motivation , Psychology, Educational , Students, Nursing/psychology
16.
Med Microbiol Immunol ; 172(4): 243-8, 1984.
Article in English | MEDLINE | ID: mdl-6371466

ABSTRACT

Thermolabile (LT) enterotoxin was prepared from stationary and shaken cultures of enterotoxigenic Escherichia coli (ETEC) grown in casamino acids-yeast extract medium and dried onto filter discs. These were then examined by a modification of the single radial immune haemolysis (SRIH) test. It was observed that LT antigenicity, as detected by this test, remained unaltered for as long as 30 days at room temperature.


Subject(s)
Bacterial Toxins/analysis , Enterotoxins/analysis , Escherichia coli Proteins , Escherichia coli/immunology , Hemolytic Plaque Technique , Bacterial Toxins/immunology , Enterotoxins/immunology , Filtration/instrumentation , Time Factors
SELECTION OF CITATIONS
SEARCH DETAIL
...