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1.
An Acad Bras Cienc ; 95(3): e20220853, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37878907

RESUMO

Some grasslands in ecotones with forests tend to be encroached by woody species, because of changes in climate and land use. Such structural changes in vegetation can be facilitated when the grassland community presents an autochthonous arboreal component, like Butia palms. We aim to identify the responses of taxonomic and functional diversity on grassland community with the occurrence of arborescent/arboreal species (autochthonous and encroaching) to palm density and grazing intensity. The study was conducted in a Butia odorata palm grove under cattle management, in Southern Brazil. To assess the taxonomic and functional composition we performed ordinations analysis with the vegetational data and using path analysis we assessed the causal relationships between variables of interest. Density of Butia odorata and woody plants were strongly positive related, suggesting a facilitation process in the establishment of arborescent plants on the grassland matrix. The abundance of less palatable plants and grazing pressure were inversely related, indicating a selection process induced by higher grazing intensity. We suggest that the grazing intensity management must be based on the autochthonous tree density, applying higher grazing intensity in areas with higher density of encroaching plants, in addition to maintaining other regions conducive to Butia palm regeneration through fallows.


Assuntos
Arecaceae , Pradaria , Animais , Bovinos , Gado , Plantas , Florestas , Árvores , Ecossistema , Biodiversidade
2.
Org Biomol Chem ; 20(12): 2462-2466, 2022 03 23.
Artigo em Inglês | MEDLINE | ID: mdl-35258067

RESUMO

The breakdown of O,O-diethyl-2,4-dinitrophenyl phosphate in formamide (FMD) solutions is assessed using kinetic studies and 31P nuclear magnetic resonance (NMR) analysis. Regiospecific nucleophilic amidolysis via P-O bond cleavage is observed, leading to non-toxic diester and FMD regeneration. In the systems evaluated, water plays an antagonistic role: while it is key for the breakdown of the reaction intermediate, it inhibits the nucleophilic activity of FMD by hydrogen bonding effects.


Assuntos
Fosfatos , Água , Cinética , Espectroscopia de Ressonância Magnética , Organofosfatos/química , Fosfatos/química , Água/química
3.
J Org Chem ; 86(5): 4027-4034, 2021 03 05.
Artigo em Inglês | MEDLINE | ID: mdl-33587642

RESUMO

Organophosphate (OP) pesticides are responsible for numerous human deaths every year. Nucleophilic substitution is an important method to mitigate the toxicity of obsolete stocks of OPs. Herein, the degradation of O,O-diethyl-2,4-dinitrophenyl phosphate (DEDNPP) and pesticide diethyl-4-nitrophenyl phosphate (Paraoxon) promoted by 1,2,4-triazole (TAZ) was investigated by means of kinetic studies, nuclear magnetic resonance (NMR) analyses, and theoretical calculations. Results showed fast degradation of OPs is promoted by the anionic form of the nucleophile (TAZ(-)) in pH > 8.5 (optimal at pH = 11). Rate enhancements of 106 and 105-fold in relation to neutral hydrolysis of DEDNPP and Paraoxon were observed, respectively, consistent with alpha-nucleophiles reactivity. TAZ(-) regioselectively promotes the degradation of DEDNPP via P-O bond break, forming a quickly hydrolyzable phosphorylated intermediate, regenerating the nucleophile. Calculations using M06-2X/6-311++G(d,p) level of theory revealed that the equivalent nitrogen atoms of TAZ(-) are the main nucleophilic center of the molecule. This study expands the knowledge on the reactivity of iminic compounds as detoxificant agents of OPs, indicating the efficiency and selectivity of TAZ(-) in aqueous medium, encouraging the design of novel TAZ-based catalysts.


Assuntos
Organofosfatos , Paraoxon , Ânions , Humanos , Hidrólise , Cinética , Triazóis
4.
Biol Sport ; 38(1): 113-121, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33795920

RESUMO

The effects of resistance training (RT) associated with calcium ß-hydroxyß-methylbutyrate (CaHMB) supplementation on the body composition and gene expression of cytokines related to skeletal muscle hypertrophy and adipose tissue metabolism were studied in rats. Male Wistar rats were divided into four groups of 12 animals: sedentary control (SC); sedentary supplemented (SS); resistance training control (RTC) and resistance training supplemented (RTS). Rats from RTC and RTS groups were submitted to an RT programme and those from SS and RTS groups received 1 mL of CaHMB (320 mg kg-1 day-1) by gavage, for 8 weeks. We evaluated: body composition; plasma lipid profile; the gene expression of interleukin (IL)-6, IL-10, IL-15 and fibronectin type III domain-containing protein 5 (FNDC-5) in skeletal muscle, and IL-6, mitochondrial uncoupling protein 1 (UCP-1) in white adipose tissue (WAT); and the concentration of irisin in WAT. Compared to RTC alone, the combination of CaHMB with RT (RTS) further reduced abdominal circumference (5.3%), Lee index (2.4%), fat percentage (24.4%), plasma VLDL cholesterol (16.8%) and triglycerides (17%) and increased the gene expression of FNDC-5 (78.9%) and IL-6 (47.4%) in skeletal muscle and irisin concentration (26.9%) in WAT. Neither RT nor CaHMB affected the protein percentage or the gene expression of IL-6 and UCP-1 in WAT and IL-10, IL-15 in skeletal muscle. In conclusion, CaHMB supplementation increased the beneficial effects of RT on body fat reduction and was associated with muscular genic expression of IL-6 and FNDC-5 and irisin concentration in WAT, despite the lack of change in protein mass and maximal strength.

5.
Chemistry ; 26(22): 5017-5026, 2020 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-32027765

RESUMO

The harmful impact caused by pesticides on human health and the environment necessitates the development of efficient degradation processes and control of prohibited stocks of such substances. Organophosphates (OPs) are among the most used agrochemicals in the world and their degradation can proceed through several possible pathways. Investigating the reactivity of OPs with nucleophilic species allows one to propose new and efficient catalyst scaffolds for use in detoxification. In light of the remarkable catalytic activity of imidazole (IMZ) at promoting dephosphorylation processes of OPs, the reactivity of 4(5)-hydroxymethylimidazole (HMZ) with diethyl-2,4-dinitrophenylphosphate (DEDNPP) and Paraoxon are evaluated by combining experimental and theoretical approaches. It is observed that HMZ is an efficient and regiospecific catalyst with reactivity modulated by competing tautomers. To propose an optimal IMZ-based catalyst, quantum chemical calculations were performed for monosubstituted 4(5)IMZ derivatives that might cleave DEDNPP. Both inductive effects and hydrogen bonding by the substituents are shown to influence barriers and mechanisms.

6.
Parasitol Res ; 114(1): 155-65, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25324134

RESUMO

Trypanosoma cruzi trypomastigotes invade a great variety of mammalian cells, with several molecules being implicated in this complex event. Herein, the sequence GGIALAG present in prokineticin-2 receptor (PKR2), selected by phage display technology, is described as a new T. cruzi receptor for the Tc85 group of glycoproteins belonging to the gp85/TS superfamily and involved in cellular invasion of mammalian hosts. This finding is confirmed by the inhibitory activity of MCF10-A (human mammary) cell invasion by T. cruzi either by anti-PKR2 antibodies (77%) or GGIALAG-synthetic peptide (42%). Furthermore, interference RNA (iRNA) inhibition of PKR2 expression in MCF10-A cells reduces T. cruzi invasion by 50%. The binding site of Tc85 to PKR2 was localized at the C-terminal end of the molecule, upstream of the conserved FLY sequence, previously implicated in parasite cell invasion. PKR2, a receptor formed by seven membrane-spanning α-helical segments, is mainly present in the central nervous system, peripheral organs, and mature blood cells. Due to its wide distribution, PKR2 could be a suitable receptor for T. cruzi natural infection, contributing to the parasite dissemination throughout the mammalian organism. These findings augment the number and diversity of possible in vivo receptors for T. cruzi and reassure the multiplicity of Tc85 binding sites to mammalian hosts.


Assuntos
Receptores Acoplados a Proteínas G/metabolismo , Receptores de Peptídeos/metabolismo , Trypanosoma cruzi/fisiologia , Animais , Bacteriófagos , Sítios de Ligação , Linhagem Celular , Sequência Conservada , Glicoproteínas/genética , Humanos , Receptores Acoplados a Proteínas G/genética , Receptores de Peptídeos/genética
7.
Cell Biochem Funct ; 32(3): 287-93, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24301255

RESUMO

We investigated the efficacy of rosmarinic acid (RA) in preventing lipid peroxidation and increased activity of acetylcholinesterase (AChE) in the brain of streptozotocin-induced diabetic rats. The animals were divided into six groups (n = 8): control, ethanol, RA 10 mg/kg, diabetic, diabetic/ethanol and diabetic/RA 10 mg/kg. After 21 days of treatment with RA, the cerebral structures (striatum, cortex and hippocampus) were removed for experimental assays. The results demonstrated that the treatment with RA (10 mg/kg) significantly reduced the level of lipid peroxidation in hippocampus (28%), cortex (38%) and striatum (47%) of diabetic rats when compared with the control. In addition, it was found that hyperglycaemia caused significant increased in the activity of AChE in hippocampus (58%), cortex (46%) and striatum (30%) in comparison with the control. On the other hand, the treatment with RA reversed this effect to the level of control after 3 weeks. In conclusion, the present findings showed that treatment with RA prevents the lipid peroxidation and consequently the increase in AChE activity in diabetic rats, demonstrating that this compound can modulate cholinergic neurotransmission and prevent damage oxidative in brain in the diabetic state. Thus, we can suggest that RA could be a promising compound in the complementary therapy in diabetes.


Assuntos
Acetilcolinesterase/metabolismo , Antioxidantes/farmacologia , Encéfalo/metabolismo , Cinamatos/farmacologia , Depsídeos/farmacologia , Diabetes Mellitus Experimental/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Animais , Diabetes Mellitus Experimental/induzido quimicamente , Masculino , Ratos , Ratos Wistar , Estreptozocina , Ácido Rosmarínico
8.
Mycologia ; 106(2): 323-7, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24782499

RESUMO

A combined dataset of rDNA ITS and LSU sequences was used to infer the phylogenetic relationships of Hydnochaete peroxydata (≡ Hydnum peroxydatum), the type species of Hydnochaete. The species was retrieved nested within the Hymenochaete s. str. clade; therefore Hydnochaete is regarded as a synonym of Hymenochaete and the new combination Hymenochaete peroxydata is proposed.


Assuntos
Basidiomycota/classificação , Basidiomycota/isolamento & purificação , Filogenia , Basidiomycota/genética , DNA Fúngico/genética , DNA Ribossômico/genética , Dados de Sequência Molecular
9.
Mar Pollut Bull ; 206: 116697, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39018822

RESUMO

The abundance of micro (MPs) and nano (NPs) sized plastic particles in the ocean is concerning due to their harmful effects on marine life. The interactions between MPs and NPs in the marine environment and their impact on marine biota remain not fully understood. This study contributes with new insights into the interaction between polystyrene NPs (PSNPs) and polyethylene MPs (PEMPs) on the clam Ruditapes decussatus. Results showed ingestion of MPs and NPs by clams, with PSNPs demonstrating higher toxicity in hemolymph. While no genotoxicity was observed, clams treated with MPs and the mixture showed increased acetylcolinesterase (AchE) activity over time. Additionally, the antioxidant defense system mitigated oxidative stress, suggesting effective neutralization of reactive oxygen species. Hazard assessment indicated the greatest impact on clam digestive glands after ten days of exposure, with an antagonistic interaction between MPs and NPs noted.


Assuntos
Bivalves , Microplásticos , Nanopartículas , Poluentes Químicos da Água , Animais , Poluentes Químicos da Água/toxicidade , Microplásticos/toxicidade , Nanopartículas/toxicidade , Poliestirenos/toxicidade , Estresse Oxidativo , Plásticos/toxicidade , Polietileno/toxicidade
10.
J Hazard Mater ; 473: 134479, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38762985

RESUMO

Once in the marine environment, fishing nets and cables undergo weathering, breaking down into micro and nano-size particles and leaching plastic additives, which negatively affect marine biota. This study aims to unravel the ecotoxicological impact of different concentrations of leachate obtained from abandoned or lost fishing nets and cables in the mussel Mytilus galloprovincialis under long-term exposure (28 days). Biochemical biomarkers linked to antioxidant defense system, xenobiotic biotransformation, oxidative damage, genotoxicity, and neurotoxicity were evaluated in different mussel tissues. The chemical nature of the fishing nets and cables and the chemical composition of the leachate were assessed and metals, plasticizers, UV stabilizers, flame retardants, antioxidants, dyes, flavoring agents, preservatives, intermediates and photo initiators were detected. The leachate severely affected the antioxidant and biotransformation systems in mussels' tissues. Following exposure to 1 mg·L-1 of leachate, mussels' defense system was enhanced to prevent oxidative damage. In contrast, in mussels exposed to 10 and 100 mg·L-1 of leachate, defenses failed to overcome pro-oxidant molecules, resulting in genotoxicity and oxidative damage. Principal component analysis (PCA) and Weight of Evidence (WOE) evaluation confirmed that mussels were significantly affected by the leachate being the hazard of the leachate concentrations of 10 mg·L-1 ranked as major, while 1 and 100 mg·L-1 was moderate. These results highlighted that the leachate from fishing nets and cables can be a threat to the heath of the mussel M. galloprovincialis.


Assuntos
Mytilus , Poluentes Químicos da Água , Animais , Mytilus/efeitos dos fármacos , Mytilus/metabolismo , Poluentes Químicos da Água/toxicidade , Estresse Oxidativo/efeitos dos fármacos , Biomarcadores/metabolismo , Antioxidantes/metabolismo , Ecotoxicologia , Dano ao DNA/efeitos dos fármacos
11.
Parasitol Res ; 112(8): 2773-82, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23681191

RESUMO

An antigenic conserved B domain was previously identified within nucleoside triphosphate diphosphohydrolases (NTPDases) of plants and parasites. Now, the r-potDomain B, a 6× His-tag polypeptide belonging to the conserved B domain from the potato apyrase, and synthetic peptides LbB1LJ and LbB2LJ derived from the B domain from Leishmania NTPDase 1 were used as molecular tools for studies of the Leishmania amazonensis NTPDase 1. Widespread subcellular location of the specific NTPDase 1 was detected by Western blots of promastigote fractions and ultrastructural immunocytochemical microscopy using immune sera raised against these biomolecules. In addition, the L. amazonensis-infected BALB/c mice were evaluated at 12 to 120 days after infection, which progresses showing typical nodular lesion. High antibody reactivity with either r-potDomain B, LbB1LJ, or LbB2LJ was found in L. amazonensis-infected BALB/c mice indicating the antigenicity of the B domain from NTPDase 1 isoform. The IgG1 antibody reactivity significantly increased at 90-120 days postinfection, 18- to 24-fold when compared to the 12th day, and remained elevated even at 120th after infection, coinciding with the most active stage of the disease. In contrast, significantly higher IgG2a antibody reactivity with each biomolecule was observed at 40th day, about two- to fourfold higher than those found at 12th or 20th day, and decreased along 120-day period. Apparently, the conserved B domain is capable to induce IgG2a production in early disease stages. All together, these results suggest that r-potDomain B or synthetic peptides could be molecular starting points in experimental protocols of immunotherapy and/or vaccination for leishmaniasis.


Assuntos
Antígenos CD/metabolismo , Apirase/metabolismo , Leishmania/enzimologia , Leishmaniose/parasitologia , Sequência de Aminoácidos , Animais , Antígenos CD/genética , Antígenos de Protozoários , Apirase/genética , Regulação Enzimológica da Expressão Gênica , Camundongos , Camundongos Endogâmicos BALB C , Anotação de Sequência Molecular , Estrutura Terciária de Proteína
12.
Ecotoxicol Environ Saf ; 92: 150-4, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23582994

RESUMO

Macrofouling bivalves are considered an ecological and technological problem worldwide. Control measures have been researched with Limnoperna fortunei, but without success. The aim of the manuscript is to test some alternatives to regulate this harmful invasive mollusk. Mortality and behavioral response (shell gaping) of Limnoperna fortunei exposed to three chemical compounds were evaluated. Values for LC50 96h were: 0.25 (0.24-0.27)mg/L NH3-N, 11.10 (7.45-16.55) mg/L MXD-100 and 88.51 (74.61-105.01)mg/L NaOH. Reduced gaping was observed beginning at concentrations of 0.31mg/L (NH3-N), 100mg/L (MXD-100) and 160mg/L (NaOH) and increased above these values. The percentage of individuals gaping after two hours at LC50 96h differed significantly (χ(2)=79.9; DF=3; p<0.001) in MXD-100 (50%), NaOH (0%), NH3-N (96.7%) and the controls (93.3%). This study contributes to the understanding of the relationship between toxicity and behavioral effects of some toxicants in L. fortunei.


Assuntos
Amônia/toxicidade , Desinfetantes/toxicidade , Hidróxido de Sódio/toxicidade , Animais , Relação Dose-Resposta a Droga , Substâncias Perigosas , Mytilidae , Medição de Risco , Testes de Toxicidade Aguda , Poluentes Químicos da Água/toxicidade
13.
Chemosphere ; 337: 139288, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37348614

RESUMO

Pollutant exposure is considered an important factor responsible for the decline in marine biodiversity of Latin American coastal ecosystems. This threat has been detected in an estuarine system in southern Brazil, which prompted an investigation into the long-term biological effects of a chronic metal contamination on resident oysters from the Laguna Estuarine System (LES). Here, we present the species- and size-specific variations of biomarker responses (catalase, glucose-6-phosphate dehydrogenase, glutathione S-transferase, and protein carbonylation) in the gills and digestive gland of Crassostrea gigas and Crassostrea gasar. In parallel, concentrations of eight metals (Al, Cd, Cr, Cu, Fe, Mn, Pb, Zn) in soft tissues were measured. Our analyses revealed that the metal levels exhibited decreasing order in both species: Zn > Fe > Al > Cu > Mn > Cd. Except for Cu and Al, metal concentrations did not differ between oyster species. Biomarker results highlighted that C. gasar presented higher antioxidant responses, whereas C. gigas showed increased biotransformation upon exposure to LES pollutants, which varied according to the tissue. However, C. gasar showed a significant higher content of protein carbonylation but was not related to metals. In our research approach, the observation of metals presence and biomarkers-related responses are considered biologically relevant from an ecotoxicological perspective and serve as a baseline for future pollution studies in estuaries of Latin America. Finally, we recommend adopting a suite of biomarkers in both C. gasar and C. gigas, regardless their size and weight, as sentinel organisms in future regional biomonitoring studies in southern Brazil.


Assuntos
Crassostrea , Poluentes Ambientais , Poluentes Químicos da Água , Animais , Brasil , Monitoramento Ambiental/métodos , Ecossistema , Cádmio/análise , Poluentes Químicos da Água/análise , Metais/análise , Biomarcadores/metabolismo , Poluentes Ambientais/análise
14.
Nanomaterials (Basel) ; 12(12)2022 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-35745394

RESUMO

In this work, flower-like molybdenum disulfide (MoS2) microspheres were produced with polyethylene glycol (PEG) to form MoS2-PEG. Likewise, gold nanoparticles (AuNPs) were added to form MoS2-PEG/Au to investigate its potential application as a theranostic nanomaterial. These nanomaterials were fully characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), photoelectron X-ray spectroscopy (XPS), Fourier-transformed infrared spectroscopy (FTIR), cyclic voltammetry and impedance spectroscopy. The produced hierarchical MoS2-PEG/Au microstructures showed an average diameter of 400 nm containing distributed gold nanoparticles, with great cellular viability on tumoral and non-tumoral cells. This aspect makes them with multifunctional characteristics with potential application for cancer diagnosis and therapy. Through the complete morphological and physicochemical characterization, it was possible to observe that both MoS2-PEG and MoS2-PEG/Au showed good chemical stability and demonstrated noninterference in the pattern of the cell nucleus, as well. Thus, our results suggest the possible application of these hybrid nanomaterials can be immensely explored for theranostic proposals in biomedicine.

15.
Parasitology ; 138(4): 481-92, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21040619

RESUMO

Trypanosoma cruzi is a protozoan parasite that infects vertebrates, causing in humans a pathological condition known as Chagas' disease. The infection of host cells by T. cruzi involves a vast collection of molecules, including a family of 85 kDa GPI-anchored glycoproteins belonging to the gp85/trans-sialidase superfamily, which contains a conserved cell-binding sequence (VTVXNVFLYNR) known as FLY, for short. Herein, it is shown that BALB/c mice administered with a single dose (1 µg/animal, intraperitoneally) of FLY-synthetic peptide are more susceptible to infection by T. cruzi, with increased systemic parasitaemia (2-fold) and mortality. Higher tissue parasitism was observed in bladder (7·6-fold), heart (3-fold) and small intestine (3·6-fold). Moreover, an intense inflammatory response and increment of CD4+ T cells (1·7-fold) were detected in the heart of FLY-primed and infected animals, with a 5-fold relative increase of CD4+CD25+FoxP3+ T (Treg) cells. Mice treated with anti-CD25 antibodies prior to infection, showed a decrease in parasitaemia in the FLY model employed. In conclusion, the results suggest that FLY facilitates in vivo infection by T. cruzi and concurs with other factors to improve parasite survival to such an extent that might influence the progression of pathology in Chagas' disease.


Assuntos
Doença de Chagas/imunologia , Glicoproteínas/química , Neuraminidase/química , Peptídeos/administração & dosagem , Trypanosoma cruzi/patogenicidade , Sequência de Aminoácidos , Animais , Linfócitos T CD4-Positivos/imunologia , Doença de Chagas/parasitologia , Sequência Conservada , Feminino , Fatores de Transcrição Forkhead/imunologia , Glicoproteínas/imunologia , Humanos , Subunidade alfa de Receptor de Interleucina-2/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Neuraminidase/imunologia , Parasitemia/imunologia , Parasitemia/parasitologia , Peptídeos/síntese química , Peptídeos/química , Peritônio/citologia , Linfócitos T Reguladores/imunologia , Trypanosoma cruzi/enzimologia , Trypanosoma cruzi/imunologia , Virulência
16.
Dentomaxillofac Radiol ; 50(3): 20200334, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33259236

RESUMO

OBJECTIVES: The aim of this study was to compare the accuracy of vertical root fracture (VRF) detection using three tomography devices and two software systems in teeth with different endodontic fillings. METHODS: The sample consisted of 45 premolars divided into 3 groups: No filling (NF, n=15); Gutta percha (GP, n=15) and Metallic Post (MP, n=15). Cone-beam computed tomography (CBCT) images were acquired in Kodak 9000 3D, Orthopantomography 300 (OP300) and PreXion 3D devices, before and after induced root fractures. Two oral radiologists analyzed all images using InVivoDental and e-Vol DX software systems. The analysis was repeated after 15 days in 30% of the sample. Data analysis compared receiver operating characteristic (ROC) curves, as well the areas under the ROC curves. Accuracy, sensitivity, specificity, positive and negative predictive value were calculated according to each tomographic device and software. Intra- and interexaminer reliability were tested using the Kappa coefficient. RESULTS: The highest accuracy was seen in the image set from the PreXion 3D, using InVivo (0.96) or e-Vol DX (0.92) in image analysis. The OP300 device presented a similar performance of the PreXion 3D in teeth with different endodontic fillings. When using e-Vol DX, the accuracy of Kodak 9000 3D improved from 0.62 to 0.74. CONCLUSIONS: The PreXion 3D device is the most accurate when detecting VRF, with a performance similar to the OP300 in endodontic filled teeth. Kodak 9000 3D is indicated for teeth without fillings, with better accuracy using e-Vol DX software.


Assuntos
Fraturas dos Dentes , Tomografia Computadorizada de Feixe Cônico , Humanos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Software , Fraturas dos Dentes/diagnóstico por imagem , Raiz Dentária/diagnóstico por imagem
17.
Parasitology ; 137(5): 773-83, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19961654

RESUMO

An ATP diphosphohydrolase (EC 3.6.1.5) activity was identified in a Leishmania (Viannia) braziliensis promastigotes preparation (Lb). Ultrastructural cytochemical microscopy showed this protein on the parasite surface and also stained a possible similar protein at the mitochondrial membrane. Isolation of an active ATP diphosphohydrolase isoform from Lb was obtained by cross-immunoreactivity with polyclonal anti-potato apyrase antibodies. These antibodies, immobilized on Protein A-Sepharose, immunoprecipitated a polypeptide of approximately 48 kDa and, in lower amount, a polypeptide of approximately 43 kDa, and depleted 83% ATPase and 87% of the ADPase activities from detergent-homogenized Lb. Potato apyrase was recognized in Western blots by IgG antibody from American cutaneous leishmaniasis (ACL) patients, suggesting that the parasite and vegetable proteins share antigenic conserved epitopes. Significant IgG seropositivity in serum samples diluted 1:50 from ACL patients (n=20) for Lb (65%) and potato apyrase (90%) was observed by ELISA technique. Significant IgG antibody reactivity was also observed against synthetic peptides belonging to a conserved domain from L. braziliensis NDPase (80% seropositivity) and its potato apyrase counterpart (50% seropositivity), in accordance with the existence of shared antigenic epitopes and demonstrating that in leishmaniasis infection the domain r82-103 from L. braziliensis NDPase is a target for the human immune response.


Assuntos
Apirase/metabolismo , Leishmania braziliensis/enzimologia , Leishmaniose Cutânea/parasitologia , Sequência de Aminoácidos , Animais , Anticorpos Antiprotozoários/sangue , Apirase/genética , Apirase/imunologia , Western Blotting , Humanos , Imunoprecipitação , Isoenzimas , Leishmania braziliensis/imunologia , Leishmania braziliensis/ultraestrutura , Leishmaniose Cutânea/imunologia , Microscopia Eletrônica , Dados de Sequência Molecular
18.
Mycologia ; 102(6): 1253-62, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20943567

RESUMO

Genus Coltricia is re-evaluated in Brazil and 10 species are accepted, namely C. barbata, C. cinnamomea, C. duportii, C. focicola, C. globispora, C. hamata, C. montagnei, C. perennis, C. permollis and C. velutina. Coltricia focicola and C. montagnei are reported respectively for the first time from South America and Brazil. Coltricia permollis and C. velutina are described as new species. Description of the new species, illustrations and a key to species of Coltricia known from the Neotropics are provided. The current knowledge of the genus in Brazil is discussed.


Assuntos
Basidiomycota/classificação , Basidiomycota/crescimento & desenvolvimento , Basidiomycota/isolamento & purificação , Brasil , Técnicas de Tipagem Micológica , Esporos Fúngicos/classificação , Esporos Fúngicos/crescimento & desenvolvimento , Esporos Fúngicos/isolamento & purificação
19.
J Inorg Biochem ; 199: 110754, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31401348

RESUMO

A series of PdII complexes with bis-(2-pyridylmethyl)glycine as a ligand of formula [PdX(bis-(2-pyridylmethyl)glycine)] where X = Cl, Br, I were prepared and the effect of the halogen nature in the antitumor activity of eight tumorigenic and one non-tumorigenic cell line was evaluated. The chloride derivative was further functionalized with a transferrin receptor binding peptide, generating the first PdII based metallopeptide. Its antitumor activity was also evaluated. However, among all the complexes, the chloride and iodine parent compounds showed the lowest GI50 values in the panel evaluated, and lowest GI50 than cisplatin in several cell lines. In contrast, the bromine derivative showed higher values of GI50 than chloride and iodine (around 30 - 50 µM). The same trend was observed for the bovine serum albumin binding constant with higher values for iodine, chlorine, and bromine in this order. In aqueous solution, the chloride is exchanged by water while the bromine and iodine are not. DNA was evaluated as a target and showed no significative interaction for all the compounds. The results suggest sulfur-rich proteins and not DNA as a target. This report represents the first PdII metallopeptide reported, its evaluation in solution and antitumor activity. This work opens the possibilities for further functionalization of PdII complexes and the importance of the halogen coordination in the design of novel metallodrugs.


Assuntos
Complexos de Coordenação/química , Complexos de Coordenação/farmacologia , Halogênios/química , Paládio/química , Peptídeos/química , Peptídeos/farmacologia , Proteínas de Ligação a Transferrina/química , Antineoplásicos/síntese química , Antineoplásicos/química , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Complexos de Coordenação/síntese química , Células HT29 , Humanos , Células MCF-7 , Espectroscopia de Ressonância Magnética , Peptídeos/síntese química , Relação Estrutura-Atividade , Difração de Raios X
20.
PLoS One ; 14(4): e0214904, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30947282

RESUMO

BACKGROUND: Acute kidney injury (AKI) is a common complication after surgery that is associated with increased morbidity and mortality. The majority of existing perioperative AKI risk prediction models are limited in their generalizability and do not fully utilize intraoperative physiological time-series data. Thus, there is a need for intelligent, accurate, and robust systems to leverage new information as it becomes available to predict the risk of developing postoperative AKI. METHODS: A retrospective single-center cohort of 2,911 adults who underwent surgery at the University of Florida Health between 2000 and 2010 was utilized for this study. Machine learning and statistical analysis techniques were used to develop perioperative models to predict the risk of developing AKI during the first three days after surgery, first seven days after surgery, and overall (after surgery during the index hospitalization). The improvement in risk prediction was examined by incorporating intraoperative physiological time-series variables. Our proposed model enriched a preoperative model that produced a probabilistic AKI risk score by integrating intraoperative statistical features through a machine learning stacking approach inside a random forest classifier. Model performance was evaluated using the area under the receiver operating characteristic curve (AUC), accuracy, and Net Reclassification Improvement (NRI). RESULTS: The predictive performance of the proposed model is better than the preoperative data only model. The proposed model had an AUC of 0.86 (accuracy of 0.78) for the seven-day AKI outcome, while the preoperative model had an AUC of 0.84 (accuracy of 0.76). Furthermore, by integrating intraoperative features, the algorithm was able to reclassify 40% of the false negative patients from the preoperative model. The NRI for each outcome was AKI at three days (8%), seven days (7%), and overall (4%). CONCLUSIONS: Postoperative AKI prediction was improved with high sensitivity and specificity through a machine learning approach that dynamically incorporated intraoperative data.


Assuntos
Injúria Renal Aguda/etiologia , Complicações Pós-Operatórias/etiologia , Adulto , Idoso , Algoritmos , Área Sob a Curva , Estudos de Coortes , Feminino , Humanos , Período Intraoperatório , Aprendizado de Máquina , Masculino , Pessoa de Meia-Idade , Modelos Estatísticos , Valor Preditivo dos Testes , Prognóstico , Estudos Retrospectivos , Fatores de Risco , Sensibilidade e Especificidade
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