Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 18 de 18
Filtrar
Mais filtros








Base de dados
Intervalo de ano de publicação
1.
SAGE Open Med Case Rep ; 12: 2050313X241229586, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38313040

RESUMO

The objective of this case report is to present the use of tenting screw bone augmentation technique for the rehabilitation of narrow horizontally deficient mandibular ridges and to evaluate the feasibility and outcomes of this approach in achieving sufficient bone volume for successful implant placement and Osseointegration. A 34-year-old woman with no significant medical history presented with bilaterally missing teeth in the lower arch. A comprehensive treatment plan was developed through assessment and Cone Beam Computed Tomography (CBCT) imaging to evaluate the ridge dimensions and plan the treatment accordingly accurately. The tenting screw technique, utilizing autogenous/autologous+allograft materials, was chosen for horizontal ridge augmentation. Bone augmentations were performed simultaneously bilaterally using tenting screws. After a 20-week healing period, CBCT scans revealed favorable bone regeneration with adequate width for successful implant placements. This case report demonstrates the potential of tenting screw bone augmentation in effectively rehabilitating mandibular ridges and achieving optimal dental implant outcomes. Further research is needed to validate these findings and assess the long-term stability and success of this technique.

2.
Diagn Cytopathol ; 52(2): E54-E58, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38031825

RESUMO

Hepatocellular carcinoma (HCC) is the most common primary liver malignancy in adults occurring in a background of cirrhosis. Peritoneal dissemination of HCC is an unusual presentation with an incidence of 2%-16%. Peritoneal metastasis of an unruptured HCC is extremely uncommon. Despite low yield, ascitic fluid cytology serves as a valuable tool for diagnostic evaluation in a patient of cirrhosis with suspicion of malignant transformation. We present a rare case scenario in an elderly female with cirrhosis where the diagnosis of peritoneal metastasis was established on ascitic fluid cytology and confirmed by immunocytochemistry. This report illustrates the unique clinical presentation of an unruptured HCC with its cytological features and a brief review of literature.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Neoplasias Peritoneais , Idoso , Feminino , Humanos , Líquido Ascítico/patologia , Carcinoma Hepatocelular/diagnóstico , Carcinoma Hepatocelular/patologia , Citologia , Cirrose Hepática/patologia , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/patologia , Neoplasias Peritoneais/diagnóstico , Neoplasias Peritoneais/patologia
3.
Heliyon ; 9(9): e20007, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37809450

RESUMO

Dual-core yarns, containing two filaments within the core of the yarn, have gained increasing commercial and research interest recently, especially in denim manufacturing. The use of multi-components in dual-core yarns allows for tailoring the properties of the yarn and denim fabric. The type of filaments and fibers and their surface characteristics play a role in fiber-to-fiber cohesion within yarn structure. However, little has been reported regarding the effect of different filaments on the properties of dual-core yarns. The objective of this study was to investigate the effect of three different filaments, T400, polyester flat (PET flat) and polyester textured (PET textured) as well as two yarn structures, siro versus non-siro, on tensile, elastic and other properties of dual-core yarns at same twist level and linear density of the yarn. The results showed that the siro spun dual-core yarn containing T400 exhibited 25% higher tenacity compared with yarns containing other filaments. However, the plastic deformation of the yarn containing PET flat filament, having a higher initial modulus, was at a relatively lower level compared with T400 and PET textured. Overall, the siro yarn structure showed lower imperfections and higher tenacity compared with the non-siro yarn structure. The dual-core yarn containing T400 showed a higher level of moisture wicking compared with other filaments which can add to the comfort properties but a similar hairiness level. The findings of this study suggest that the use of a filament with a higher initial modulus can improve the stretch and recovery behavior of the dual-core yarns.

4.
Pharmaceuticals (Basel) ; 16(6)2023 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-37375754

RESUMO

One homoleptic (1) and three heteroleptic (2-4) palladium(II) complexes were synthesized and characterized by various physicochemical techniques, i.e., elemental analysis, FTIR, Raman spectroscopy, 1H, 13C, and 31P NMR. Compound 1 was also confirmed by single crystal XRD, showing a slightly distorted square planar geometry. The antibacterial results obtained via the agar-well diffusion method for compound 1 were maximum among the screen compounds. All the compounds have shown good to significant antibacterial results against the tested bacterial strains, Escherichia coli, Klebsiella pneumonia, and Staphylococcus aureus, except 2 against Klebsiella pneumonia. Similarly, the molecular docking study of compound 3 has shown the best affinity with binding energy scores of -8.6569, -6.5716, and -7.6966 kcal/mol against Escherichia coli, Klebsiella pneumonia, and Staphylococcus aureus, respectively. Compound 2 has exhibited the highest activity (3.67 µM), followed by compound 3 (4.57 µM), 1 (6.94 µM), and 4 (21.7 µM) against the DU145 human prostate cancer cell line using the sulforhodamine B (SRB) method as compared to cisplatin (>200 µM). The highest docking score was obtained for compounds 2 (-7.5148 kcal/mol) and 3 (-7.0343 kcal/mol). Compound 2 shows that the Cl atom of the compound acts as a chain side acceptor for the DR5 receptor residue Asp B218 and the pyridine ring is involved in interaction with the Tyr A50 residue via arene-H, while Compound 3 interacts with the Asp B218 residue via the Cl atom. The physicochemical parameters determined by the SwissADME webserver revealed that no blood-brain barrier (BBB) permeation is predicted for all four compounds, while gastrointestinal absorption is low for compound 1 and high for the rest of the compounds (2-4). As concluding remarks based on the obtained in vitro biological results, the evaluated compounds after in vivo studies might be a good choice for future antibiotics and anticancer agents.

5.
Bioinorg Chem Appl ; 2022: 2694487, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35340420

RESUMO

The carbonaceous adsorbents, an activated carbon (AC) and a bioinorganic nanocomposite (MAC), were prepared using Dalbergia sissoo sawdust as waste biomass, in this study. Both the adsorbents were characterized by FTIR, EDX, SEM, XRD, TG/DTA, surface area, and a pore size analyzer. The adsorbents were used for the removal of an antibiotic, doxycycline (DC) antibiotic, from wastewater in order to minimize a load of antibiotics in industrial effluents and consequently the drug resistance problem. Initially, the effectiveness of adsorbent was confirmed using batch adsorption experiments where isothermal models like Langmuir, Freundlich Temkin, Jovanovic, and Harkins-Jura were utilized to govern the maximum adsorption capacity of AC and MAC while pseudo-first- and second-order kinetic models were used to estimate the values of different kinetic parameters. Langmuir model best accommodated the equilibrium data whereas the pseudo-second-order kinetic model finest trimmed the kinetics data. The effect of pH on adsorption was also evaluated where maximum removal was observed between pH 5 and 7 by both adsorbents. The effect of temperature on adsorption was evaluated where the entropy change (ΔS 0) comes out to have a numerically positive value whereas Gibbs free energy change (ΔG 0) and enthalpy change (ΔH 0) were negative indicating the spontaneous nature and feasibility of the procedure. The robust technology of membrane separation is rapidly replacing the conventional technologies but at the same time suffers from the problem of membrane fouling. As pretreatment, the AC and MAC were used in hybrid with ultrafiltration (UF), nanofiltration (NF), and reverse osmosis (RO) membranes whereas permeate fluxes and percent retention of DC were compared for naked membrane operations and AC/membrane and MAC/membrane process. The permeate fluxes for MAC/membrane processes were greater as compared to AC/membrane and naked membrane processes showing the effectiveness of the bioinorganic composite as foul control and consequently recovery of DC from effluents. The percent retention of the UF membrane was lower as compared to NF and RO membranes. Improvement in percent retention for UF/AC, UF/MAC, NF/AC, NF/MAC, RO/AC, and RO/MAC was observed. The bioinorganic composite MAC contains a magnetic iron oxide which was effectively removed from slurry after use through the magnetic process and that was the main reason for high permeate fluxes in MAC/membrane operations.

6.
J Glob Antimicrob Resist ; 27: 142-149, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34517141

RESUMO

Plasmodium falciparum, the causative agent of malaria, has been developing resistance to several drugs worldwide for more than five decades. Initially, resistance was against drugs such as chloroquine, pyrimethamine, sulfadoxine, mefloquine and quinine. Research studies are now reporting parasites with resistance to the most effective and novel drug used against malaria infection worldwide, namely artemisinin. For this reason, the first-line treatment strategy of artemisinin-based combination therapy is becoming unsuccessful in areas where drug resistance is highly prevalent. The increase in artemisinin-resistant P. falciparum strains has threatened international efforts to eliminate malarial infections and to reduce the disease burden. Detection of several phenotypes that display artemisinin resistance, specification of basic genetic factors, the discovery of molecular pathways, and evaluation of its clinical outcome are possible by the current series of research on genomics and transcriptomic levels in Asia and Africa. In artemisinin resistance, slow parasite clearance among malaria-infected patients and enhanced in vitro survival of parasites occurs at the early ring stage. This resistance is due to single nucleotide polymorphisms within the Kelch 13 gene of the parasite and is related to significantly upregulated resistance signalling pathways; thus, the pro-oxidant action of artemisinins can be antagonised. New strategies are required to halt the spread of artemisinin-resistant malarial parasites.


Assuntos
Antimaláricos , Artemisininas , Resistência a Medicamentos , Malária Falciparum , Antimaláricos/farmacologia , Artemisininas/farmacologia , Humanos , Malária Falciparum/tratamento farmacológico , Proteínas de Protozoários
7.
Front Chem ; 9: 711190, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34976944

RESUMO

A new bisbenzylisoquinoline named as chondrofolinol (1) and four reported compounds (2-5) were isolated and characterized from the roots of Berberis glaucocarpa Stapf. Anti-inflammatory, anti-pyretic, and leishmanicidal studies were performed against carrageenan-induced paw edema, yeast-induced pyrexia, and the promastigotes of Leishmania tropica, respectively. The new compound significantly reduced the paw volume in carrageenan-induced paw edema and rectal temperature in yeast-induced pyrexia at 10 and 20 mg/ kg of body weight. Chondrofolinol caused almost 100% inhibition of the promastigotes of Leishmania tropica. All the compounds displayed minimal cytotoxicity against THP-1 monocytic cells. In order to ascertain the potential macromolecular targets of chondrofolinol responsible for the observed anti-inflammatory and anti-leishmanial activities, a molecular docking study was carried out on relevant protein targets of inflammation and Leishmania. Protein targets of human endoplasmic reticulum aminopeptidase 2 (ERAP2) and human matrix metalloproteinase-1 (MMP-1) for inflammation and protein targets of N-myristoyltransferase (NMT), tyrosyl-tRNA synthetase (TyrRS), and uridine diphosphate-glucose pyrophosphorylase (UGPase) for Leishmania major were selected after thorough literature search about protein targets responsible for inflammation and Leishmania major. Chondrofolinol showed excellent docking to ERAP2 and to MMP-1. The Leishmania major protein targets with the most favorable docking scores to chondrofolinol were NMT, TyrRS, and UGPase. The study indicated that bisbenzylisoquinoline and isoquinoline alkaloids possess anti-pyretic, anti-inflammatory, and anti-leishmanial properties with minimal cytotoxicity and therefore, need to be further explored for their therapeutic potential.

8.
J Biomed Nanotechnol ; 16(4): 492-504, 2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-32970981

RESUMO

To minimize the hazardous effect of physical and chemical synthesis of nanoparticles we focused on the green synthesis of nanoparticles. Nanotechnology is a research hotspot and catch great attention because of its versatile applications in medical, biosciences and engineering fields. Purpose of our recent study is to synthesize bio-inspired metallic silver NPs by root mediated Zingiber officianale extract. The synthesized Ag-NPs were further characterized by using UVVisible spectroscopy, XRD, EDX, SEM, TEM and DLS techniques. The extent of crystallites were confirmed by X-ray diffraction. SEM and TEM revealed the morphological features with size of nanoparticles between 17.3 and 41.2 nm. FTIR analysis confirmed the capping of nanoparticles by bio active constituents present in Zingiber officinale extract. Later EDX confirmed the elemental composition of nanoparticles. Zeta potential, PDI and hydrodynamic size of Ag-NPs were confirmed by DLS. The synthesize Ag-NPs possess eminent biological potency against bacterial and leishmanial strains. Moreover considerable anti-diabetic, anticancer, antioxidant and biocompatibility nature of Ag-NPs was elucidated. The highest antioxidant activity of 50.61± 1.12%, 38.22 ± 1.18% and 27.39 ± 0.92 at 200 g/mL for TAC, TRP DPPH and was observed respectively. Ag-NPs exhibit potent leishmanicidal activity of 80% ± 1.4 against promastigotes and 77% ± 1.6 against amastigotes cultures of L. tropica. Highest antidiabetic activity 30 ± 0.77% recorded at 200 µg/ml. Highest Brine shrimps cytotoxicity of Ag-NPs was 60 ± 1.18 at 200 g/ml. Maximum dye degradation for Ag-NPs was recorded as 94.1% at 140 minute. All UTI isolates were resistant to antibiotics not coated with Ag-NPs. By applying 1% of Ag-NPs highest activity was recorded as 25 ± 1.58 mm against K. pneumoniae. Maximum zone of inhibition for Ag-NPs coated with Imipenem antibiotics 26 ± 1.5 mm against K. pneumoniae and coated with Ciprofloxacin 26 ± 1.4 m against S. aureus were measured. Last but not least high biocompatible nature of Ag-NPs was observed against fresh RBCs making the ecofriendly biosynthesized silver NPs a multi-dimensional candidate in biomedical field.


Assuntos
Nanopartículas Metálicas , Zingiber officinale , Antibacterianos/farmacologia , Extratos Vegetais/farmacologia , Prata , Staphylococcus aureus
9.
Bioorg Chem ; 98: 103727, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32179285

RESUMO

Organic selenium compounds are widely associated with numerous pharmacological properties. However, selenium compounds, such as Ebselen (Ebs) and Diphenyl Diselenide (DPDS), could interact with mitochondrial respiratory complexes, especially with thiol groups. The present study evaluated whether the insertion of functional groups, o-methoxy, and p-methyl on organic selenium compounds promotes changes in mitochondrial functioning parameters and whether this is related to antibacterial activity. Here we tested some in vitro parameters after the exposure of mitochondria to different concentrations of ß-selenoamines 1-phenyl-3-(p-tolylselanyl)propan-2-amine (C1) and 1-(2-methoxyphenylselanyl)-3-phenylpropan-2-amine (C2) and analogs of DPDS 1,2-bis(2-methoxyphenyl)diselenide (C3) and 1,2-bisp-tolyldiselenide (C4). We also evaluated the antibacterial activity of ß-selenoamines and diselenides against Methicillin-resistant Staphylococcus aureus and Escherichia coli. Our results showed that o-methoxy insertion increased the antioxidant properties, without affecting the mitochondrial membrane potential. The compounds with a p-methyl insertion affected the mitochondrial membrane potential and significantly decreased the State III respiration and RCR. Besides, the p-methyl compounds presented antibacterial activity at lower concentrations than those shown in o-methoxy, precisely by the same mechanism that promotes damage to thiol groups and better absorption in gram-positive bacteria due to their relationship with cell wall constituents. Finally, our study confirms that structural modifications in organic selenium compounds provide changes in mitochondrial functioning but also raise their antibacterial effect. This strategy can be used as a target for the development of new enough potent antibacterial to restrict the advance of resistant bacterial infections.


Assuntos
Antibacterianos/farmacologia , Escherichia coli/efeitos dos fármacos , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Mitocôndrias Hepáticas/efeitos dos fármacos , Compostos Organosselênicos/farmacologia , Animais , Antibacterianos/síntese química , Antibacterianos/química , Relação Dose-Resposta a Droga , Masculino , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Estrutura Molecular , Compostos Organosselênicos/síntese química , Compostos Organosselênicos/química , Ratos , Ratos Wistar , Relação Estrutura-Atividade
10.
Int J Nanomedicine ; 14: 5087-5107, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31371949

RESUMO

Background: Nanotechnology explores a variety of promising approaches in the area of material sciences on a molecular level, and silver nanoparticles (AgNPs) are of leading interest in the present scenario. This review is a comprehensive contribution in the field of green synthesis, characterization, and biological activities of AgNPs using different biological sources. Methods: Biosynthesis of AgNPs can be accomplished by physical, chemical, and green synthesis; however, synthesis via biological precursors has shown remarkable outcomes. In available reported data, these entities are used as reducing agents where the synthesized NPs are characterized by ultraviolet-visible and Fourier-transform infrared spectra and X-ray diffraction, scanning electron microscopy, and transmission electron microscopy. Results: Modulation of metals to a nanoscale drastically changes their chemical, physical, and optical properties, and is exploited further via antibacterial, antifungal, anticancer, antioxidant, and cardioprotective activities. Results showed excellent growth inhibition of the microorganism. Conclusion: Novel outcomes of green synthesis in the field of nanotechnology are appreciable where the synthesis and design of NPs have proven potential outcomes in diverse fields. The study of green synthesis can be extended to conduct the in silco and in vitro research to confirm these findings.


Assuntos
Química Verde/métodos , Nanopartículas Metálicas/química , Nanotecnologia/métodos , Prata/química , Antibacterianos/farmacologia , Materiais Biocompatíveis/farmacologia
11.
Environ Sci Pollut Res Int ; 26(14): 14339-14349, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30868463

RESUMO

Thermodynamic and kinetic aspects for the biosorptive removal of Pb, Cd, and Cr metals from water using Chemically Modified Leaves of Salvia moorcroftiana (CMSML) were determined. Different parameters including pH, temperature, metal's initial concentration, biomass dosage, and contact time were optimized. Optimum biosorptions of Pb, Cd, and Cr were attained at pH values of 6.0, 7.0, and 3.0 respectively. Batch experiments showed maximum removal of both Pb and Cd at 40 °C and that of Cr at 30 °C. Biosorption capability of CMSML was observed to decrease with raising temperature. Optimal equilibrium times for Pb, Cd, and Cr uptake were 120, 60, and 120 min respectively. Based on the values of regression correlation coefficients (R2), the current data is explained better by applying Langmuir isotherms than the Freundlich model. Maximum biosorbent capabilities (qmax) for Pb, Cd, and Cr were approximately 270.27, 100.00, and 93.45 mg/g respectively. Thermodynamically, removal of all the three metal ions was shown to be exothermic and spontaneous.


Assuntos
Cádmio/análise , Cromo/análise , Chumbo/análise , Folhas de Planta/crescimento & desenvolvimento , Salvia/crescimento & desenvolvimento , Poluentes Químicos da Água/análise , Adsorção , Biodegradação Ambiental , Biomassa , Concentração de Íons de Hidrogênio , Cinética , Modelos Teóricos , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/metabolismo , Salvia/efeitos dos fármacos , Salvia/metabolismo , Termodinâmica
13.
Toxicol Rep ; 2: 961-967, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26726309

RESUMO

Organic selenium compounds possess numerous biological properties, including antioxidant activity. Yet, the high toxicity of some of them, such as diphenyl diselenide (DPDS), is a limiting factor in their current usage. Accordingly, we tested four novel organic selenium compounds in the non-parasite nematode Caenorhabditis elegans and compared their efficacy to DPDS. The novel organic selenium compounds are ß-selenoamines (1-phenyl-3-(p-tolylselanyl)propan-2-amine (C1) and 1-(2-methoxyphenylselanyl)-3-phenylpropan-2-amine (C2) and analogs of DPDS (1,2-bis (2-methoxyphenyl) diselenide (C3) and 1,2-bisp-tolyldiselenide (C4). Synchronized worms at the L4 larval stage were exposed for one hour in M9 buffer to these compounds. Oxidative stress conditions were induced by juglone (200 µM) and heat shock (35 °C). Moreover, we evaluated Caenorhabditis elegans behavior, GST-4::GFP (glutathione S-transferase) expression and the activity of acetylcholinesterase (AChE). All tested compounds efficiently restored viability in juglone stressed worms. However, DPDS, C2, C3 and C4 significantly decreased the defecation cycle time. Juglone-induced GST-4::GFP expression was not attenuated in worms pretreated with the novel compounds, except with C2. Finally, AChE activity was reduced by DPDS, C2, C3 and C4. To our knowledge, this is study firstly showed the effects of C1, C2, C3 and C4 selenium-derived compounds in Caenorhabditis elegans. Low toxic effects were noted, except for reduction in the defecation cycle, which is likely associated with AChE inhibition. The juglone-induced stress (reduced viability) was fully reversed by compounds to control animal levels. C2 was also efficient in reducing the juglone-induced GST-4::GFP expression, suggesting the latter may mediate the stress induced by this compound. Future studies could be profitably directed at addressing additional molecular mechanisms that mediate the protective effects of these novel organic selenium compounds.

14.
Fish Physiol Biochem ; 40(1): 141-9, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23877622

RESUMO

Several diets employed in aquaculture are enriched with selenium (Se), as it is a fundamental element to aquatic vertebrates. Diphenyl diselenide [(PhSe)2], which is a synthetic organoselenium compound, has been considered a potential antioxidant agent in different experimental models. Thus, the aim of this study was to evaluate the effects of dietary diphenyl diselenide at concentrations of 1.5, 3.0, and 5.0 mg/kg for 60 days and to determine its optimal supplemental level for carp, Cyprinus carpio. Neither growth retardation nor hepatoxicity was induced by the inclusion of diphenyl diselenide at concentrations ranging from 1.5 to 5.0 mg/kg. In addition, the inclusion of 3.0 mg/kg of diphenyl diselenide stimulated the weight and length of the carp. The supplementation with 1.5 and 3.0 mg/kg of diphenyl diselenide did not produce oxidative damage in the tissues, verified by peroxidation lipid and protein carbonyl assays. However, at 5.0 mg/kg, it caused an increase of the lipid peroxidation in the liver, brain, and muscle, and inhibited the cerebral acetylcholinesterase activity. An increase of the hepatic superoxide dismutase activity and non-protein thiols content in all tissues and ascorbic acid in the liver, gills, and brain was verified in carp fed with the diet containing 3.0 mg/kg of diphenyl diselenide. This diet had advantageous effects for the fish used in experiments. Therefore, this compound could be considered a beneficial dietary supplement for carp nutrition.


Assuntos
Derivados de Benzeno/administração & dosagem , Carpas , Compostos Organosselênicos/administração & dosagem , Acetilcolinesterase/metabolismo , Fenômenos Fisiológicos da Nutrição Animal , Animais , Aquicultura , Derivados de Benzeno/efeitos adversos , Peso Corporal/efeitos dos fármacos , Catalase/metabolismo , Dieta , Glutationa Transferase/metabolismo , Fígado/efeitos dos fármacos , Fígado/enzimologia , Compostos Organosselênicos/efeitos adversos , Sintase do Porfobilinogênio/sangue , Carbonilação Proteica/efeitos dos fármacos , Compostos de Sulfidrila/metabolismo , Superóxido Dismutase/metabolismo , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismo
15.
Toxicol In Vitro ; 27(5): 1433-9, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23499633

RESUMO

This study was designed to examine the antioxidant activity in vitro of novel mono- and diselenide compounds. We compared whether the formation of p-methyl-selenol from compounds 1-phenyl-3-(p-tolylselanyl)propan-2-amine (C1) and 1,2-dip-tolyldiselenide (C4) and o-methoxy-selenol from compounds 1-(2-methoxyphenylselanyl)-3-phenylpropan-2-amine (C2) and 1,2-bis(2-methoxyphenyl)diselenide (C3) may be involved in their antioxidant effects. The compounds were tested against Fe(II) and sodium nitroprusside (SNP)-induced lipid peroxidation in rat brain and liver homogenates. Likewise, the antioxidant capacity of the compounds was assessed by their ability to decolorize the DPPH radical as well as the Fe(II) chelating assay through the reduction of molybdenum(VI) (Mo6+) to molybdenum(V) (Mo5+). This colorimetric assay was also used to quantify thiol peroxidase (GPx) and oxidase activity and thioredoxin reductase (TrxR) activity. The results showed that the novel selenide compounds inhibit the thiobarbituric acid reactive species (TBARS) induced by different pro-oxidants, but the monoselenides effects were significant only at concentrations higher than the concentrations of the diselenides. Similarly, the total antioxidant activity was higher in the diselenides. Moreover, GPx and TrxR activity was only observed for the diselenides, which indicates that these compounds are more stable selenol molecules than monoselenides.


Assuntos
Antioxidantes/farmacologia , Encéfalo/efeitos dos fármacos , Fígado/efeitos dos fármacos , Compostos Organosselênicos/farmacologia , Animais , Encéfalo/metabolismo , Glutationa Peroxidase/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Fígado/metabolismo , Masculino , NADP/metabolismo , Oxirredução , Ratos , Ratos Wistar , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismo , Tiorredoxina Redutase 1/metabolismo
16.
Environ Toxicol Pharmacol ; 34(2): 446-453, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22797322

RESUMO

ß-Seleno amines were screened for in vitro antioxidant activity. The compounds (C1-C4) were tested against lipid peroxidation induced by iron and sodium nitroprusside in rat brain and liver homogenates. The compounds showed inhibition against thiobarbituric acid reactive species (TBARS) induced by different pro-oxidants (10µM FeSO(4) and 5µM sodium nitroprusside (SNP) in rat brain and liver homogenates. The compounds exhibited strong antioxidant activity in 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical and phosphomolybdenum assays. The IC(50) values revealed that the ß-seleno amines in which the amino group was protected with protecting groups tert-butyloxycarbonyl (Boc) and Tosyl (Ts) groups showed better antioxidant profiles compared to the free monoselenides. The total antioxidant activity of C1, C2, C3 and C4 were found to be 85.2±11.5, 114±7.9, 138±8.5, 125.81±5.2µM/ml of ascorbic acid respectively. Therefore, these compounds may be used as synthetic antioxidants.


Assuntos
Aminas/farmacologia , Antioxidantes/farmacologia , Peroxidação de Lipídeos/efeitos dos fármacos , Compostos Organosselênicos/farmacologia , Animais , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Compostos Ferrosos , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Nitroprussiato , Ratos , Ratos Wistar , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismo
17.
Mol Cell Biochem ; 365(1-2): 85-92, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22311601

RESUMO

The antioxidant properties of organoselenium compounds have been extensively investigated because oxidative stress is a hallmark of a variety of chronic human diseases. Here, we reported the influence of substituent groups in the antioxidant activity of ß-selenoamines. We have investigated whether they exhibited glutathione peroxidase-like (GPx-like) activity and whether they could be substrate of thioredoxin reductase (TrxR). In the DPPH assay, the ß-selenium amines did not exhibit antioxidant activity. However, the ß-selenium amines with p-methoxy and tosyl groups prevented the lipid peroxidation. The ß-selenium amine compound with p-methoxy substituent group exhibited thiol-peroxidase-like activity (GPx-like activity) and was reduced by the hepatic TrxR. These results contribute to understand the influence of structural alteration of non-conventional selenium compounds as synthetic mimetic of antioxidant enzymes of mammalian organisms.


Assuntos
Sequestradores de Radicais Livres/química , Compostos Organosselênicos/química , Peroxidases/química , Animais , Compostos de Bifenilo/química , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Catálise , Sequestradores de Radicais Livres/farmacologia , Radicais Livres/química , Peroxidação de Lipídeos , Fígado/enzimologia , Masculino , NADP/química , Compostos Organosselênicos/farmacologia , Oxirredução , Peroxidases/farmacologia , Picratos/química , Ratos , Ratos Wistar , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismo , Tiorredoxina Dissulfeto Redutase/química , Tiorredoxina Dissulfeto Redutase/isolamento & purificação
18.
Health Phys ; 96(2 Suppl): S5-10, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19125056

RESUMO

An intercomparison exercise for personal dosimetry service providers within Pakistan was conducted by the Health Physics Division of the Pakistan Institute of Nuclear Science and Technology. Participation in the exercise was on voluntary basis. The exercise was carried out to harmonize individual dose monitoring techniques for high energy photons in terms of a new operational quantity, namely personal dose equivalent Hp(10), for personal dosimetry in accordance with the recommendations of the International Commission on Radiation Units and Measurements. Each laboratory submitted 25 dosimeters for participation in the intercomparison exercise. Protection level Co and Cs sources were used for irradiation of dosimeters on a water phantom according to International Atomic Energy Agency protocol at the Secondary Standard Dosimetry Laboratory. Hp(10) doses for five different dose levels were measured by the participating laboratories. The ratios of measured dose/true dose (Hm/Ht) remained in the range of 0.66 to 1.11 for the Co source and 0.84 to 1.17 for the Cs source. Performance of service providers' laboratories to measure Hp(10) doses was analyzed and evaluated in terms of trumpet curves plotted for photons at a 95% confidence level.


Assuntos
Exposição Ocupacional/análise , Monitoramento de Radiação/normas , Proteção Radiológica/normas , Medição de Risco/normas , Carga Corporal (Radioterapia) , Radioisótopos de Césio , Radioisótopos de Cobalto , Humanos , Laboratórios , Exposição Ocupacional/prevenção & controle , Paquistão , Fótons , Controle de Qualidade , Doses de Radiação
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA