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1.
Pituitary ; 27(2): 187-196, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38273189

RESUMO

PURPOSE: To prospectively evaluate the usefulness of T1-weighted imaging (T1WI) and diffusion-weighted imaging (DWI) sequences in predicting the consistency of macroadenomas. In addition, to determine their values ​​as prognostic factors of surgical outcomes. METHODS: Patients with pituitary macroadenoma and surgical indication were included. All patients underwent pre-surgical magnetic resonance imaging (MRI) that included the sequences T1WI before and after contrast administration and DWI with the apparent diffusion coefficient (ADC) map. Post-surgical MRI was performed at least 3 months after surgery. The consistency of the macroadenomas was evaluated at surgery, and they were grouped into soft and intermediate/hard adenomas. Mean ADC values, signal on T1WI and the ratio of tumor ADC values ​​to pons (ADCR) were compared with tumor consistency and grade of surgical resection. RESULTS: A total of 80 patients were included. A softened consistency was found at surgery in 53 patients and hardened in 27 patients. The median ADC in the soft consistency group was 0.532 × 10-3 mm2/sec (0.306 - 1.096 × 10-3 mm2/sec), and in the intermediate/hard consistency group was 0.509 × 10-3 mm2/sec (0.308 - 0.818 × 10-3 mm2/sec). There was no significant difference between the median values ​​of ADC, ADCR and signal on T1W between the soft and hard tumor groups, or between patients with and without tumor residue. CONCLUSION: Our results did not show usefulness of the DWI and T1WI for assessing the consistency of pituitary macroadenomas, nor as a predictor of the degree of surgical resection.


Assuntos
Adenoma , Neoplasias Hipofisárias , Humanos , Neoplasias Hipofisárias/diagnóstico por imagem , Neoplasias Hipofisárias/cirurgia , Neoplasias Hipofisárias/patologia , Imagem de Difusão por Ressonância Magnética/métodos , Imageamento por Ressonância Magnética/métodos , Adenoma/diagnóstico por imagem , Adenoma/cirurgia , Adenoma/patologia , Estudos Retrospectivos
2.
Microb Pathog ; 180: 106119, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37098385

RESUMO

Streptococcus pneumoniae is a bacterium that causes serious infections, including pneumonia. The limited range of available vaccines and the rise of antibiotic-resistant bacteria mean that new treatments are needed. This study looked at the potential of quercetin as an antimicrobial agent against S. pneumoniae in both isolation and in biofilms. The researchers used microdilution tests, checkerboard assays, and death curve assays, as well as in silico and in vitro cytotoxicity evaluations. They found that quercetin at a concentration of 125.0 µg/mL had both inhibitory and bactericidal effects against S. pneumoniae, and these effects were increased when quercetin was combined with ampicillin. Quercetin also reduced the growth of pneumococcal biofilms. In addition, quercetin (absence or in combination with ampicillin) reduced the death time of Tenebrio molitor larvae compared to the infection control. The study also demonstrated that quercetin had low toxicity in both in silico and in vivo assays, suggesting that it could be a promising treatment for infections caused by S. pneumoniae.


Assuntos
Anti-Infecciosos , Infecções Pneumocócicas , Humanos , Streptococcus pneumoniae , Quercetina/farmacologia , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Anti-Infecciosos/farmacologia , Ampicilina/farmacologia , Testes de Sensibilidade Microbiana , Infecções Pneumocócicas/tratamento farmacológico , Infecções Pneumocócicas/microbiologia
3.
Analyst ; 148(2): 305-315, 2023 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-36541436

RESUMO

Microcystins (MCs) are highly toxic peptides produced by cyanobacteria during algal blooms. Microcystin-leucine-arginine (MC-LR) is the most toxic and common MC variant with major effects on human and animal health upon exposure. MC-LR detection has become critical to ensure water safety, therefore robust and reliable analytical methods are needed. This work reports the development of a simple and optimized Molecularly Imprinted Nanoparticle-Based Assay (MINA) for MC-LR detection in water. Molecularly Imprinted Nanoparticles (MINs) were prepared by solid-phase polymerization on glass beads conjugated to MC-LR through (3-aminopropyl) triethoxysilane (APTES) via amide bonding. APTES-modified glass beads were obtained under optimized conditions to maximize the density of surface amino groups available for MC-LR conjugation. Two quinary mixtures of acrylic monomers differing in charge, polarity, and functionality were selected from molecular docking calculations and used to obtain MINs for MC-LR recognition using N,N'-methylene-bis-acrylamide (BIS) as the crosslinking agent. MINs were immobilized by physical adsorption onto 96-well polystyrene microplate and evaluated as per their rebinding capacity toward the analyte by using a covalent conjugate between MC-LR and the enzyme horseradish peroxidase (HRP). Experimental conditions for the MINs immobilization protocol, HRP-MC-LR concentration, and composition of the blocking solution were set to maximize the colorimetric response of the MINs compared to non-treated wells. Optimized conditions were then applied to conduct competitive MINAs with the HRP-MC-LR conjugate and the free analyte, which confirmed the preferential binding of MC-LR to the immobilized MINs for analyte concentrations ranging from 1 × 10-5 nmol L-1 to 100 nmol L-1. The best competitive MINA showed a limit of detection of 2.49 × 10-4 nmol L-1 and coefficients of variation less than 10% (n = 6), which are auspicious for the use of MINs as analytical tools for MC-LR detection below the permissible limits issued by WHO for safe water consumption (1.00 nmol L-1). This assay also proved to be selective to the analyte in cross-reactivity studies with two analogous microcystins (MC-RR and MC-YR). Analyses of lagoon and drinking water samples enriched with MC-LR revealed strong matrix effects that reduce the MINA response to the analyte, thus suggesting the need for sample pretreatment methods in future development in this subject.


Assuntos
Água Potável , Microcistinas , Água Potável/análise , Toxinas Marinhas , Microcistinas/análise , Simulação de Acoplamento Molecular
4.
An Acad Bras Cienc ; 95(3): e20220856, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37909564

RESUMO

The properties of adhesive mortars can change due to heating, compromising the durability of the coating systems. The aim of this article was to evaluate the influence of cement and polymer contents on the tensile bond strength of adhesive mortars after thermal storage. Ceramic tiling system specimens were prepared with seventeen formulations of adhesive mortars. These specimens were stored under dry (reference) at temperature of 23 ± 2 °C and 60 ± 5% of relative humidity and thermal (temperature of 70 ± 2 °C) conditions. The results showed that the cement content was the major factor concerning tensile bond strength. The vinyl acetate-ethylene (VAE) polymer improved the tensile bond strength of mortars under thermal storage. However, the hydroxypropyl methyl cellulose (HPMC) content contributed to the tensile bond strength only when higher cement contents were used. Besides, microstructure analysis showed that ettringite was degraded during thermal storage.


Assuntos
Adesivos , Polietilenos , Cimentos de Resina/química , Resistência à Tração , Polímeros , Metilcelulose , Propriedades de Superfície
5.
J Fish Biol ; 2023 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-37812457

RESUMO

An opportunistic rescue of a stranded 6 m giant manta ray off Ilha Comprida, in São Paulo, southeastern Brazil, revealed a new technique for returning large bodied mobulid rays to the water once beached. The technique, adapted from protocols to move stranded cetaceans, was modified to suit the dorso-ventrally compressed shape of mobulid rays and reduce damage to the animal while being pulled back into deeper water. The method and suggestions for its improvement have been described with the intention of assisting in the rescue of other stranded large mobulids.

6.
J Environ Manage ; 326(Pt A): 116655, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36368206

RESUMO

The iron ore mining activity results in considerable waste production and impacts on surrounding ecosystems. Natural recovery of impacted areas is absent or occurs slowly, especially when associated with prolonged dry seasons in tropical regions. The objective of this work was to unveil the mechanisms of Paspalum densum (Poir.) grass to overcome the periods of seasonal drought and its metal accumulation in areas impacted by iron mining, a tailings storage facilities and surrounding ferruginous grassland in Brazil. Lower mortality was observed among individuals in the tailings storage facilities, with a 74.3% survival rate. In contrast, after the beginning of the dry season, all individuals died in the ferruginous grassland. The plants in the tailings deposits showed better nutrition, with a higher concentration of P, Cu, Fe, Zn, Mn and greater capacity to accumulate Pb and Cd over time. Pb was the element with highest bioconcetration factor (BCF) and bioaccumulation coefficient (BAC), while Mn was the one with the highest translocation factor (TF). The dry season resulted in reduced chlorophyll a, b and total and effective quantum yield of photosystem II (PSII) of P. densum individuals. However, the plants in the tailings storage facilities showed adjustments to overcome the effects of drought, with an increase in the concentration of proline in leaves and reduction of oxidative damage (MDA and H2O2) at the end of the dry season. The grass P. densum showed rapid acclimatization in the tailings storage facilities and resistance to drought through antioxidant and photosynthetic adjustments and was still able to bioaccumulate and translocate in plant tissues some metals present in the iron ore impacted sites.


Assuntos
Metais Pesados , Poluentes do Solo , Oligoelementos , Humanos , Poaceae , Poluentes do Solo/análise , Clorofila A , Ecossistema , Peróxido de Hidrogênio , Chumbo , Ferro/análise , Plantas
7.
Neurogenetics ; 23(3): 167-177, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35397036

RESUMO

The syndromic group of hereditary spastic paraplegias has a heterogeneous clinical profile and a broad differential diagnosis, including neurometabolic disorders that are potentially treatable. This group includes 5,10-methylenetetrahydrofolate reductase deficiency, cobalamin C deficiency disease, dopamine responsive dystonia, cerebrotendinous xanthomatosis, biotinidase deficiency, GLUT1 deficiency syndrome, delta-e-pyrroline-carboxylase-synthetase deficiency, hyperonithinemia-hyperammonemia-homocitrullinuria syndrome, arginase deficiency, multiple carboxylase deficiency, and X-linked adrenoleukodystrophy. This review describes these diseases in detail, highlighting the importance of early diagnosis and effective treatment aiming at preserving functionality and quality of life in these patients. For the purpose of this study, we carried a non-systematic review on PUBMED, finding an initial sample of 122 papers; upon refining, 41 articles were found relevant to this review. Subsequently, we added review articles and works with historical relevance, totalizing 76 references. An adequate diagnostic workup in patients presenting with spastic paraplegia phenotype should include screening for these rare conditions, followed by parsimonious ancillary investigation.


Assuntos
Homocistinúria , Paraplegia Espástica Hereditária , Humanos , Espasticidade Muscular , Qualidade de Vida , Paraplegia Espástica Hereditária/diagnóstico , Paraplegia Espástica Hereditária/genética , Paraplegia Espástica Hereditária/metabolismo , Deficiência de Vitamina B 12/congênito
8.
Photosynth Res ; 154(3): 259-276, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36181569

RESUMO

Nitrogen (N) deficiency represents an important limiting factor affecting photosynthetic productivity and the yields of crop plants. Significant reported differences in N use efficiency between the crop species and genotypes provide a good background for the studies of diversity of photosynthetic and photoprotective responses associated with nitrogen deficiency. Using distinct wheat (Triticum aestivum L.) genotypes with previously observed contrasting responses to nitrogen nutrition (cv. Enola and cv. Slomer), we performed advanced analyses of CO2 assimilation, PSII, and PSI photochemistry, also focusing on the heterogeneity of the stress responses in the different leaf levels. Our results confirmed the loss of photosynthetic capacity and enhanced more in lower positions. Non-stomatal limitation of photosynthesis was well reflected by the changes in PSII and PSI photochemistry, including the parameters derived from the fast-fluorescence kinetics. Low photosynthesis in N-deprived leaves, especially in lower positions, was associated with a significant decrease in the activity of alternative electron flows. The exception was the cyclic electron flow around PSI that was enhanced in most of the samples with a low photosynthetic rate. We observed significant genotype-specific responses. An old genotype Slomer with a lower CO2 assimilation rate demonstrated enhanced alternative electron flow and photorespiration capacity. In contrast, a modern, highly productive genotype Enola responded to decreased photosynthesis by a significant increase in nonphotochemical dissipation and cyclic electron flow. Our results illustrate the importance of alternative electron flows for eliminating the excitation pressure at the PSII acceptor side. The decrease in capacity of electron acceptors was balanced by the structural and functional changes of the components of the electron transport chain, leading to a decline of linear electron transport to prevent the overreduction of the PSI acceptor side and related photooxidative damage of photosynthetic structures in leaves exposed to nitrogen deficiency.


Assuntos
Clorofila , Triticum , Triticum/genética , Clorofila/genética , Nitrogênio , Elétrons , Dióxido de Carbono , Genótipo
9.
Rev Esp Enferm Dig ; 113(8): 563-569, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33267594

RESUMO

INTRODUCTION: hepatic osteodystrophy, including osteoporosis, is an abnormal bone metabolism related with chronic liver diseases. Osteoporosis is associated with an increased risk of bone fractures, with a significant impact on morbidity, mortality and healthcare costs. Nevertheless, bone disorders tend to be undervalued in cirrhosis due to alcohol-related liver disease (ALD cirrhosis). This study aimed to assess the prevalence of hepatic osteodystrophy and osteoporosis in ALD cirrhosis. METHODS: a prospective observational study was performed that included patients with ALD cirrhosis, between September 2017 and December 2018. Bone mineral density was determined by dual energy X-ray absorptiometry at the lumbar spine and the femoral neck. Hepatic osteodystrophy was defined as a T-score below -1 SD and osteoporosis as a T-score below -2.5 SD. RESULTS: ninety-four patients were included; 24.5 % (n = 23) had prior fragility fractures and ten patients suffered new osteoporotic fractures during the study period. Hepatic osteodystrophy was diagnosed in 79.8 % (n = 75) and osteoporosis in 21.3 % (n = 20) of cases. Patients with hepatic osteodystrophy presented significantly worse Child-Turcotte-Pugh (p < 0.05) and Model for End-Stage Liver Disease (MELD-sodium) scores (p = 0.01). According to the multivariate analysis, lower body mass index (BMI) (OR = 0.787, 95 % CI: 0.688-0.901, p = 0.001) and vitamin D deficiency (OR = 6.798, 95 % CI: 1.775-26.038, p = 0.005) were significantly and independently associated with hepatic osteodystrophy. Patients with osteoporosis also had a lower BMI (p = 0.01). Female patients and those with prior fragility fractures were more likely to suffer from osteoporosis (p < 0.05). CONCLUSION: our study revealed a high prevalence of hepatic osteodystrophy and osteoporosis in patients with ALD cirrhosis (particularly in those with a lower BMI) and a concerning high rate of fragility fractures. Bone mineral density should be assessed in order to allow for an early diagnosis and the implementation of preventive measures.


Assuntos
Doença Hepática Terminal , Hepatopatias , Absorciometria de Fóton , Densidade Óssea , Feminino , Humanos , Cirrose Hepática/complicações , Cirrose Hepática/epidemiologia , Fatores de Risco , Índice de Gravidade de Doença
10.
Int J Colorectal Dis ; 35(4): 769-773, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32006136

RESUMO

BACKGROUND: Eosinophilic enterocolitis is a rare condition included in the spectrum of the eosinophilic gastrointestinal disorders. Diagnosis is based on clinical presentation combined with an increase infiltration of eosinophils in the gastrointestinal tract, in the absence of other secondary causes of eosinophilic infiltration. CASE PRESENTATION: We report a case of a 22-year-old male with eosinophilic enterocolitis presenting with malabsorption syndrome (diarrhea, vomiting, weight loss), bowel wall thickening, and ascites. Secondary causes of intestinal eosinophilia were excluded, and diagnosis was established in a timely manner. Treatment plan included a 6-food elimination diet and corticosteroid therapy, with clinical remission after 2 weeks of therapy. The patient remains asymptomatic after 12 months of follow-up, with no relapse.


Assuntos
Ascite/complicações , Diarreia/complicações , Abdome/diagnóstico por imagem , Ascite/sangue , Ascite/diagnóstico por imagem , Ascite/patologia , Líquido Ascítico/patologia , Diarreia/sangue , Diarreia/diagnóstico por imagem , Diarreia/patologia , Endoscopia , Humanos , Masculino , Ultrassonografia , Adulto Jovem
11.
Appl Opt ; 59(31): 9710-9714, 2020 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-33175807

RESUMO

The testing of astigmatism and field curvature of an optical system with light-field imaging is proposed. The method consists in measuring the depth map, obtained with a plenoptic camera, of the image of a test pattern formed by the optical system. To demonstrate the accuracy of the method, the virtual image formed by a plano-convex lens was tested. The resulting depth map was compared with the sagittal and tangential foci distances calculated with the Coddington theory. The proposed method could be applied to the quality testing of ocular optics, including eyeglasses, eyepieces, virtual reality goggles, and augmented reality devices.

12.
Artif Organs ; 43(7): 688-693, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30589443

RESUMO

This article presents experimental and computational results of electroporation in rat liver. The experiments were performed using different forms of electrodes and waveforms of applied electric pulses. For the numerical simulation, the electroporation model proposed by Ramos and Weinert in a previous publication was used. Dynamic adjustments were used for obtaining a good modeling of the electric current. A single set of model parameters was obtained to fit the simulated current response for different waveforms and electrodes. These parameters were obtained with the use of a genetic algorithm that minimized the error between the simulated and experimental currents. The electroporation model with dynamic adjustment proved to be an appropriate simulation tool to predict the tissue conductivity during stimulation by intense electrical fields.


Assuntos
Simulação por Computador , Eletroporação/métodos , Fígado/fisiologia , Modelos Biológicos , Algoritmos , Animais , Condutividade Elétrica , Eletricidade , Eletrodos , Eletroporação/instrumentação , Desenho de Equipamento , Ratos Wistar
14.
J Environ Sci (China) ; 78: 257-266, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30665644

RESUMO

The revegetation of mined areas poses a great challenge to the iron ore mining industry. The initial recovery process in degraded areas might rely on the use of Fe-resistant grasses. Tropical grasses, such as Paspalum densum and Echinochloa crus-galli, show different resistance strategies to iron toxicity; however, these mechanisms are poorly understood. The Fe-resistance mechanisms and direct iron toxicity as a function of root apex removal were investigated. To achieve this purpose, both grass species were grown for up to 480 hr in a nutrient solution containing 0.019 or 7 mmol/L Fe-EDTA after the root apices had been removed or maintained. Cultivation in the presence of excess iron-induced leaf bronzing and the formation of iron plaque on the root surfaces of both grass species, but was more significant on those plants whose root apex had been removed. Iron accumulation was higher in the roots, but reached phytotoxic levels in the aerial parts as well. It did not hinder the biosynthesis of chloroplastidic pigments. No significant changes in gas exchange and chlorophyll a fluorescence occurred in either grass when their roots were kept intact; the contrary was true for plants with excised root apices. In both studied grasses, the root apoplastic barriers had an important function in the restriction of iron translocation from the root to the aerial plant parts, especially in E. crus-galli. Root apex removal negatively influenced the iron toxicity resistance mechanisms (tolerance in P. densum and avoidance in E. crus-galli).


Assuntos
Adaptação Fisiológica/fisiologia , Biodegradação Ambiental , Ferro/toxicidade , Poaceae/metabolismo , Poluentes do Solo/toxicidade , Clorofila A/metabolismo , Folhas de Planta/metabolismo , Raízes de Plantas/metabolismo , Brotos de Planta/metabolismo , Clima Tropical
15.
Eye Contact Lens ; 44 Suppl 2: S233-S240, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29077584

RESUMO

OBJECTIVES: The objective of this investigation was to evaluate the level of comfort and ocular dryness during wear with six daily disposable contact lenses (DDCL) and also determine the changes in contact lens equilibrium water content (EWC) resulting from their wear. METHODS: In this contralateral open trial, 27 subjects were randomly fitted with six DDCL (stenfilcon A, delefilcon A, nelfilcon A, narafilcon A, nesofilcon A, and omafilcon A). The evaluation of comfort and ocular dryness sensation was recorded by the participants at two moments of the day (11 AM and 5 PM) over a period of 10 days of contact lens wear. The assessment was made with the aid of visual analogue scales (0-10). The refractive index of 54 contact lenses was accessed by a single operator using a digital automated refractometer (CLR 12-70; Index Instruments). The EWC of the lenses was estimated based on its refractive index values. RESULTS: Comfort ratings were slightly higher for delefilcon A (9.56±0.67, P=0.01) and narafilcon A (9.40±0.93, P=0.01) and these lenses wearers also reported less ocular dryness. The results revealed a pronounced water content reduction for omafilcon A (P=0.002), narafilcon A (P=0.008), and nesofilcon A (P=0.003). CONCLUSION: Although changes in subjective responses and EWC were distinct among the materials analyzed, all the contact lenses performed well during the 10 days of wear.


Assuntos
Lentes de Contato Hidrofílicas , Síndromes do Olho Seco/prevenção & controle , Dor Ocular/diagnóstico , Adulto , Lentes de Contato Hidrofílicas/efeitos adversos , Lentes de Contato Hidrofílicas/normas , Equipamentos Descartáveis , Feminino , Humanos , Masculino , Satisfação do Paciente , Refratometria , Água/análise
16.
Rev Esp Enferm Dig ; 110(2): 123, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29278001

RESUMO

An 84-years old woman, medicated with acenocumarol, was admitted to the Emergency Room with lower abdominal pain and nauseas and no history of trauma. She was medicated with acenocumarol and had a non-measurable international normalized ratio. The findings of the bowel ultrasound, ileocolonoscopy and biopsies specimens were suggestive of intramural bleeding of the ileum, ileocecal valve and cecum. Spontaneous intramural bleeding of the gastrointestinal wall associated with oral anticoagulation is rare.


Assuntos
Anticoagulantes/efeitos adversos , Hemorragia Gastrointestinal/induzido quimicamente , Idoso de 80 Anos ou mais , Anticoagulantes/uso terapêutico , Ceco/patologia , Feminino , Hemorragia Gastrointestinal/diagnóstico por imagem , Hemorragia Gastrointestinal/patologia , Humanos , Íleo/patologia , Mucosa Intestinal/patologia
18.
Metab Brain Dis ; 32(2): 359-368, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-27714582

RESUMO

We evaluated the in vitro effects of galactose at 0.1, 3.0, 5.0 and 10.0 mM on thiobarbituric acid-reactive substances (TBA-RS), total sulfhydryl content, protein carbonyl content, on the activities of the antioxidant enzymes catalase (CAT), superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) and on acetylcholinesterase (AChE) activity in the cerebral cortex, cerebellum and hippocampus of rats. We also investigated the influence of the antioxidants (each at 1 mM), α-tocopherol, ascorbic acid and glutathione, on the effects elicited by galactose on the parameters tested. Results showed that galactose, at a concentration of 3.0 mM, enhanced TBA-RS levels in the hippocampus, cerebral cortex and cerebellum of rats. In the cerebral cortex, galactose at concentrations of 5.0 and 10.0 mM increased TBA-RS and protein carbonyl content, and at 10.0 mM increased CAT activity and decreased AChE activity. In the cerebellum, galactose at concentrations of 5.0 and 10.0 mM increased TBA-RS, SOD and GSH-Px activities. In the hippocampus, galactose at concentrations of 5.0 and 10.0 mM increased TBA-RS and CAT activity and at 10.0 mM decreased GSH-Px. Data showed that at the pathologically high concentration (greater than 5.0 mM), galactose induces lipid peroxidation, protein carbonylation, alters antioxidant defenses in the cerebrum, and also alters cholinesterase activity. Trolox, ascorbic acid and glutathione addition prevented the majority of alterations in oxidative stress parameters and the decrease in AChE activity that were caused by galactose. Our findings lend support to a potential therapeutic strategy for this condition, which may include the use of appropriate antioxidants for ameliorating the damage caused by galactose.


Assuntos
Acetilcolinesterase/metabolismo , Antioxidantes/farmacologia , Cérebro/metabolismo , Galactose/farmacologia , Fármacos Neuroprotetores/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Animais , Ácido Ascórbico/farmacologia , Catalase/metabolismo , Cérebro/efeitos dos fármacos , Cérebro/enzimologia , Glutationa/farmacologia , Glutationa Peroxidase/metabolismo , Técnicas In Vitro , Masculino , Carbonilação Proteica/efeitos dos fármacos , Ratos , Ratos Wistar , Superóxido Dismutase/metabolismo , alfa-Tocoferol/farmacologia
19.
Ecotoxicol Environ Saf ; 144: 307-314, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28645032

RESUMO

Tropical woody species occurring in limestone outcrops are frequently exposed to particulate material from cement factories. The effects of 60-day cement dust exposure on physiological traits and enzymatic antioxidant system of young plant leaves of Guazuma ulmifolia Lam., Myracrodruon urundeuva Allemão and Trichilia hirta L. were investigated. Cement dust (2.5 or 5mgcm-2) was applied to the leaf surface or soil or both (leaf plus soil) and plants were maintained at greenhouse. Cement dust barely affected the mineral nutrient levels, except for iron whose content was decreased in leaves/leaflets of all species studied. The incident light was partly blocked in cement dust-treated leaves, regardless of the plant species, causing a decrease in the photosynthetic pigments in M. urundeuva. The chlorophyll b content, however, increased in G. ulmifolia and T. hirta leaves upon cement dust treatment. The potential quantum yield of photosystem II in challenged leaves of G. ulmifolia was 3.8% lower than that of control plants, while such trait remained unaffected in the leaves of the other species. No changes in leaf stomatal conductance and antioxidant enzymes activities were observed, except for M. urundeuva, which experienced a 31% increment in the superoxide dismutase activity upon 5mgcm-2 cement dust (leaf plus soil treatment), when compared with control plants. Overall, the mild changes caused by cement dust in the in physiological and biochemical traits of the species studied indicate that such species might be eligible for further studies of revegetation in fields impacted by cement factories.


Assuntos
Poluentes Atmosféricos/toxicidade , Antioxidantes/metabolismo , Materiais de Construção/toxicidade , Poeira/análise , Magnoliopsida/fisiologia , Folhas de Planta/metabolismo , Poluentes Atmosféricos/análise , Materiais de Construção/análise , Ferro/metabolismo , Fotossíntese/efeitos dos fármacos , Complexo de Proteína do Fotossistema II/metabolismo , Folhas de Planta/efeitos dos fármacos , Solo/química , Especificidade da Espécie , Clima Tropical
20.
Amino Acids ; 47(9): 1931-9, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25894889

RESUMO

In the present study, we evaluated the in vitro effects of homoarginine (hArg) at 1, 10 and 20 µM on thiobarbituric acid-reactive substances (TBA-RS), total sulfhydryl content and on the activity of the antioxidant enzymes catalase (CAT), superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) in plasma, erythrocytes, kidney and liver of rats (60 days old). We also investigated the influence of the antioxidants (each at 1 mM) α-tocopherol and ascorbic acid, as well as of the nitric oxide synthase inhibitor N (G)-nitro-L-arginine methyl ester (L-NAME) at 1 mM, on the effects elicited by hArg on the parameters tested. In plasma, hArg at concentrations of 10 and 20 µM decreased moderately the total sulfhydryl content. At 20 µM, hArg enhanced moderately TBA-RS in the plasma. In plasma, the effects of hArg (20 µM) on TBA-RS and total thiol content were abolished by α-tocopherol, ascorbic acid and L-NAME. At all concentrations tested, hArg did not exert any effect on CAT, SOD or GSH-Px activity in the erythrocytes. In the kidney, hArg exerted effects only at 20 µM and in a different manner: TBA-RS levels increased and total thiol content and CAT activity decreased, while SOD and GSH-Px activity increased. In the renal medulla, α-tocopherol and ascorbic acid but not L-NAME abolished the effects of hArg (20 µM) on TBA-RS, while all agents inhibited the hArg-induced increase in SOD activity. In the renal cortex, α-tocopherol, ascorbic acid and L-NAME abolished the effects of hArg (20 µM) on the total sulfhydryl content and GSH-Px activity, but L-NAME did not reverse the inhibitory effects of hArg on CAT activity. In the liver, no effects of hArg were observed of all biomarkers measured. At the pathologically high concentration of 20 µM, as it may occur in plasma in hyperargininemia, hArg may enhance lipid peroxidation and thiol oxidation and inhibit CAT activity, but may increase SOD and GSH-Px activity predominantly in the kidney.


Assuntos
Ácido Ascórbico/farmacologia , Eritrócitos/metabolismo , Homoarginina/farmacologia , Rim/metabolismo , Fígado/metabolismo , NG-Nitroarginina Metil Éster/farmacologia , Estresse Oxidativo/efeitos dos fármacos , alfa-Tocoferol/farmacologia , Animais , Masculino , Ratos , Ratos Wistar
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