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1.
Molecules ; 25(8)2020 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-32326289

RESUMO

Subarachnoid hemorrhage (SAH) accounts for 3% of all strokes. As more and more data indicates the role of oxidative stress in acute brain damage caused by SAH, an attempt was made to correlate the clinical status of patients with systemic level of antioxidants and lipid peroxidation products. The hemorrhage was diagnosed with brain computed tomography (CT) and aneurysm with angio-CT and angiography, while the vasospasm was monitored with transcranial Doppler. Plasma glutathione peroxidase activity (GSH-Px) and vitamin A, E, and C levels were determined spectrophotometrically and by HPLC, respectively. The levels of polyunsaturated fatty acids (PUFAs) cyclization products were determined by GC-MS, while F2-isoprostanes and neuroprostanes (NP) were determined by LC-MS. SAH was accompanied by changes in antioxidant capacity in blood plasma, including initially (day 1) an increase in GSH-Px activity, followed by its decrease and a progressive decrease in glutathione (GSH) levels and vitamins A, E, and C. On the other hand, levels of PUFAs cyclization products, F2-isoprostanes, and neuroprostanes were highest on day 1 (two and eight times higher, respectively) and decreased over time. The levels of 4-HNE (4-hydroxynonenal), 4-ONE (4-oxononenal), and MDA (malondialdehyde) changed similarly. In contrast, the 4-HHE (4-hydroxyhexenal) level reduced after SAH increased significantly after a week. It was found that the deterioration of the overall clinical and neurological condition of SAH patients due to cerebral edema, intracranial hemorrhage, or vasoconstriction corresponded to reduced antioxidant defense and, as a consequence, increased lipid peroxidation and slower observed changes in regression. It can be concluded that monitoring the level of lipid peroxidation products (neuroprostanes, 4-ONE, and MDA) can support the monitoring of the clinical status of patients, especially with regard to the assessment of vasospasm.


Assuntos
Peroxidação de Lipídeos , Oxirredução , Hemorragia Subaracnóidea/diagnóstico , Hemorragia Subaracnóidea/metabolismo , Adulto , Idoso , Antioxidantes , Biomarcadores , Feminino , Humanos , Metabolismo dos Lipídeos , Lipídeos/sangue , Masculino , Pessoa de Meia-Idade , Estresse Oxidativo , Prognóstico , Espécies Reativas de Oxigênio/metabolismo , Índice de Gravidade de Doença , Hemorragia Subaracnóidea/sangue , Hemorragia Subaracnóidea/etiologia , Fatores de Tempo
2.
Adv Clin Exp Med ; 27(5): 673-680, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29790685

RESUMO

BACKGROUND: Intracranial aneurysms are common, occurring in about 1-2% of the population. Saccular aneurysm is a pouch-like pathological dilatation of an intracranial artery that develops when the cerebral artery wall becomes too weak to resist hemodynamic pressure and distends. OBJECTIVES: The aim of this study was to determine whether the development of intracranial aneurysms and subarachnoid hemorrhage (SAH) affects neuronal phospholipid metabolism, and what influence different invasive treatments have on brain free radical phospholipid metabolism. MATERIAL AND METHODS: The level of polyunsaturated fatty acid (PUFA) cyclization products - F2-isoprostanes and F4-neuroprostanes - was examined using liquid chromatography - mass spectrometry (LC-MS) in the plasma of patients with brain aneurysm and resulting subarachnoid hemorrhage. RESULTS: It was revealed that an aneurysm leads to the enhancement of lipid peroxidation with a significant increase in plasma F2-isoprostanes and F4-neuroprostanes (more than 3-fold and 11-fold, respectively) in comparison to healthy subjects. The rupture of an aneurysm results in hemorrhage and an additional increase in examined prostaglandin derivatives. The embolization and clipping of aneurysms contribute to a gradual restoration of metabolic homeostasis in brain cells, which is visible in the decrease in PUFA cyclization products. CONCLUSIONS: The results indicate that aneurysm development is associated with enhanced inflammation and oxidative stress, factors which favor lipid peroxidation, particularly in neurons, whose membranes are rich in docosahexaenoic acid, a precursor of F4-neuroprostanes.


Assuntos
F2-Isoprostanos/sangue , Aneurisma Intracraniano/diagnóstico , Peroxidação de Lipídeos , Neuroprostanos/sangue , Fosfolipídeos/metabolismo , Biomarcadores/sangue , Estudos de Casos e Controles , Cromatografia Líquida/métodos , Cromatografia Gasosa-Espectrometria de Massas/métodos , Humanos , Aneurisma Intracraniano/sangue , Estresse Oxidativo , Espectrometria de Massas em Tandem/métodos
3.
Mol Biol Rep ; 41(11): 7121-32, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25063578

RESUMO

Salmonella enterica subsp. enterica comprises a number of serovars, many of which pose an epidemiological threat to humans and are a worldwide cause of morbidity and mortality. Most reported food infection outbreaks involve the serovars Salmonella Enteritidis and Salmonella Typhimurium. Rapid identification to determine the primary sources of the bacterial contamination is important to the improvement of public health. In recent years, many DNA-based techniques have been applied to genotype Salmonella. Herein, we report the use of a manual TRS-PCR approach for the differentiation of the Salmonella enterica subspecies enterica serovars in a single-tube assay. One hundred seventy Salmonella strains were examined in this work. These consisted of serovars S. Enteritidis, S. Typhimurium, S. Infantis, S. Virchow, S. Hadar, S. Newport and S. Anatum. Five of the TRS-primers, N6(GTG)4, N6(CAC)4, N6(CGG)4, N6(CCG)4 and N6(CTG)4, perfectly distinguished the S. Enteritidis and S. Typhimurium serovars, and the N6(GTG)4 primer additionally grouped the other five frequently isolated serovars. In our opinion, the TRS-PCR methodology could be recommended for a quick and simple DNA-based test for inter-serovar discrimination of Salmonella strains.


Assuntos
Técnicas Bacteriológicas/métodos , Microbiologia de Alimentos/métodos , Reação em Cadeia da Polimerase/métodos , Salmonella/genética , Sorogrupo , Análise por Conglomerados , Primers do DNA/genética , Salmonella/isolamento & purificação , Especificidade da Espécie
4.
Med Sci Monit ; 18(11): CS105-8, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23111746

RESUMO

BACKGROUND: There is a vast discrepancy between the incidence of skull base metastases reported in vivo and at autopsy. Asymptomatic character or unspecific symptoms make the diagnosis difficult, particularly in patients with no history of cancer. Our case illustrates a skull base metastasis from breast cancer, detected in a diagnostic process initiated by ophthalmologic examination. CASE REPORT: We report the case of a 53-year-old woman complaining of ptosis and diplopia, with concomitant loss of skin sensation within the right half of the forehead, and without any other worrisome symptoms or signs. Ophthalmic examination revealed impairment in eye movements, slight proptosis and corneal hypoesthesia on the right side, with normal pupillary light reflexes. The anterior and posterior segments of the eye were normal. Based on CT and MRI, an extensive tumor was detected, infiltrating the right orbit and the frontotemporal region of the skull base, and producing edema of the adjacent aspects of the brain. Aside from partial palsy of the oculomotor nerve and the ophthalmic division of the trigeminal nerve, no abnormalities were found on neurological examination. Explorative craniotomy and histopathological findings revealed a skull base metastasis from breast cancer. CONCLUSIONS: Diplopia, ptosis, proptosis, and ophthalmic nerve sensory loss may be the only manifestation of a skull base metastasis. Careful ophthalmologic examination is crucial in early detection of this life-threatening condition.


Assuntos
Neoplasias da Mama/complicações , Neoplasias da Mama/patologia , Oftalmopatias/etiologia , Neoplasias da Base do Crânio/secundário , Oftalmopatias/diagnóstico por imagem , Oftalmopatias/fisiopatologia , Feminino , Fixação Ocular , Humanos , Imageamento por Ressonância Magnética , Pessoa de Meia-Idade , Radiografia , Neoplasias da Base do Crânio/diagnóstico por imagem
5.
Mol Biol Rep ; 39(7): 7681-6, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22350162

RESUMO

Mycobacterium avium, a member of the group of non-tuberculous mycobacteria, is most often responsible for the serious diseases in humans and is frequently isolated from NTM-caused pulmonary events. In this connection the epidemiological aspect is also of great importance. Here we present a useful genetic assay that uses (CCG)(4)-based PCR for genotyping M. avium. After applying this test to 33 strains of M. avium, we found a discriminatory index of 0.979. The accuracy of this analysis was supported by a reasonable reproducibility of 95.1%. These results were compared with the Mycobacterial Intergenic Repeat Unit-Variable Number Tandem Repeats (MIRU-VNTR) typing scheme which had slightly lower discriminatory index of 0.945 however, the method was able to cluster different strains compared to CCG-PCR. Taking into account high discriminatory index and reproducibility, this test scheme has the potential as a screening tool in the investigation of M. avium infections, especially if combined with MIRU-VNTR.


Assuntos
DNA Intergênico/genética , Repetições Minissatélites , Complexo Mycobacterium avium/classificação , Complexo Mycobacterium avium/genética , Infecção por Mycobacterium avium-intracellulare/diagnóstico , Genótipo , Humanos , Tipagem Molecular , Reação em Cadeia da Polimerase/métodos
6.
Exp Mol Pathol ; 87(3): 234-8, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19761764

RESUMO

The pathogenesis of age-related macular degeneration (AMD) is thought to be determined by an array of environmental and genetic factors. The association of increased expression of vascular endothelial growth factor (VEGF) with AMD, especially the wet form of AMD, was reported in several studies. The VEGF gene is highly polymorphic and some of its polymorphisms may affect its expression. In our work, we searched for an association between the -460C> (rs833061) and -634G>C (rs2010963) polymorphisms of the VEGF gene and the occurrence of AMD and its dry and wet forms. We have chosen these polymorphisms because they were shown to be significant in other studies and we previously showed their association with diabetic retinopathy. A total of 401 individuals were enrolled in this study: 136 controls, and 88 patients with dry and 177 with wet AMD. The polymorphisms were determined with DNA from peripheral blood lymphocytes by allele-specific and restriction fragment length polymorphism polymerase chain reaction. The significance of the polymorphisms was assessed by multiple logistic regression, producing odds ratios (ORs) and 95% confidence intervals (CIs). We observed a weak association (OR 2.90) between AMD occurrence and the C/T genotype of the -460C>T polymorphism. An association (OR 3.77) between the C/T genotype of the -460C>T polymorphism and the occurrence of dry AMD was observed. The T/T genotype considerably lowered the risk of dry AMD (OR 0.19). Dry AMD was associated with the C/C genotype of the -634G>C polymorphism (OR 3.68). Another weak association (OR 2.63) was found between the C/T genotype of the -460C>T polymorphism and the occurrence of wet AMD. The occurrence of AMD was correlated with the presence of the combined C/T-G/G genotype of both polymorphisms (OR 2.41), whereas the T/T-G/G and T/T-G/C genotypes exerted a protective effect against the disease (OR 0.22 and 0.48, respectively). The presence of the C/T-G/G and C/T-C/C combined genotypes increased the risk of dry AMD (OR 2.08 and 3.77, respectively), whereas the presence of the T/T-G/G and T/T-G/C genotypes decreased the risk (OR 0.15 and 0.28, respectively). In the wet form of AMD, the combined genotype C/T-G/G slightly favored the disease (OR 2.61) and the T/T-G/G genotype had a protective effect (OR 0.25). Analysis of haplotypes of both polymorphisms yielded similar results for AMD in general as well as for the dry and wet forms of the disease: the CG haplotype favored both forms of AMD, whereas the TG haplotype protected against both forms of AMD. The results obtained indicate that the -460C>T and -634G>C polymorphisms of the VEGF gene may be associated with the dry and wet forms of AMD in a Polish population.


Assuntos
Degeneração Macular/genética , Fator A de Crescimento do Endotélio Vascular/genética , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Polônia , Polimorfismo Genético
7.
Klin Oczna ; 111(4-6): 168-73, 2009.
Artigo em Polonês | MEDLINE | ID: mdl-19673452

RESUMO

Oxidative stress is a major factor in the pathogenesis of age-related macular degeneration (AMD). Retinal pigment epithelial (RPE) cells are prone to reactive oxygen species (ROS) arising during the stress due to intense oxygen metabolism and a high oxygen pressure. Additionally, the cells can be exposed to ROS as a consequence of accumulation of iron ions in these cells, sunlight exposure and tobacco smoke. There are several defense systems against RTF in the cell, including antioxidant enzymes, low-molecular weight antioxidants and DNA repair pathways. RPE cells display phagocytic activity towards outer segments of photoreceptors and this activity can be associated with additional oxidative stress since the segments are rich in long chain, polyunsaturated fatty acids (PUFA). The oxidation of PUFA leads to the production of additional ROS. Moreover, oxidized PUFA are not correctly cleaved in the lysosomes of RPE and are accumulated in the form of lipofuscin, which is deposited in Bruch's membrane in the form of drusen and in this way it stimulates immune responses, including phagocytosis, associated with the recruiting of macrophages and dendritic cells. In this time, RPE cells are exposed to ROS, produced in oxygen burst associated with phagocytosis. Further studies, both clinical/epidemiological and in vitro, are needed to better understand relationship between AMD and oxidative stress.


Assuntos
Envelhecimento/metabolismo , Degeneração Macular/etiologia , Degeneração Macular/metabolismo , Estresse Oxidativo , Lâmina Basilar da Corioide/metabolismo , Humanos , Oxidantes/metabolismo , Epitélio Pigmentado Ocular/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Retina/metabolismo , Fumar/efeitos adversos , Luz Solar/efeitos adversos
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