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1.
J Med Syst ; 43(7): 190, 2019 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-31111236

RESUMO

The significance of pattern recognition techniques is widely enhanced in image processing and medical applications. Thus, lesion segmentation method is an essential technique of pattern recognition algorithms to detect the melanoma skin cancer in patients at earliest stage, otherwise, in further stages it becomes one of the deadliest disease and its mortality rate is very high. Therefore, a precise melanoma segmentation technique is introduced based on the Gradient and Feature Adaptive Contour (GFAC) model to detect melanoma skin cancer in earliest stage and diagnosis of dermoscopic images. In the proposed image segmentation technique pre-processing and noise elimination techniques are introduced to decrease noise and make execution faster. This technique helps in separating the required entity from the background and gather the information from the adjacent pixels of similar classes. Multiple Gaussian distributed patterns are adopted to extract efficient features and to get precise segmentation. The proposed GFACmodel is noise free and consist of smoother border. The segmentation model efficiency is tested on PH2 dataset. The superiority of the proposed modified gradient and feature adaptive contour model can be verified against various state-of-art-techniques in terms of segmented image, error reduction and efficient feature extraction.


Assuntos
Detecção Precoce de Câncer , Interpretação de Imagem Assistida por Computador/métodos , Melanoma/diagnóstico , Neoplasias Cutâneas/diagnóstico , Algoritmos , Humanos , Processamento de Imagem Assistida por Computador/métodos , Distribuição Normal , Melanoma Maligno Cutâneo
2.
Eur J Neurol ; 21(2): 299-304, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24894998

RESUMO

BACKGROUND AND PURPOSE: Progressive multifocal leukoencephalopathy (PML) is caused by reactivation of JC virus (JCV) infection due to combined host and viral factors. Anti-JCV antibodies provide a means to assess JCV exposure and stratify PML risk. The reported seroprevalence of anti-JCV antibodies varies from 39% to 91% depending on assay methodology and population studied. A two-step anti-JCV antibody assay (STRATIFY JCV™; Focus Diagnostics, Cypress, CA, USA) detected anti-JCV antibodies in approximately 55% of multiple sclerosis (MS) patients. This study describes the prevalence of anti-JCV antibodies in a large, multinational MS population. METHODS: This cross-sectional epidemiology study was designed to enroll a minimum of 2000 patients with an MS diagnosis of any type, irrespective of treatment, from Europe, Canada and Australia. Anti-JCV antibody prevalence was determined by STRATIFY JCV; the effects of demographic and disease characteristics were evaluated. RESULTS: A total of 7724 patients from 10 countries participated in the study. Overall anti-JCV antibody prevalence was 57.1% (95% confidence interval 56.0%-58.2%). Seroprevalence was significantly associated with increasing age, gender and country of current residence (P < 0.0001). No significant differences in anti-JCV antibody prevalence were associated with MS disease characteristics, including duration and type of MS and number and duration of MS therapies. CONCLUSIONS: Overall seroprevalence of anti-JCV antibodies in MS patients from Europe, Canada and Australia was consistent with previous studies using the STRATIFY JCV assay. Anti-JCV prevalence differed significantly by age, gender and country, but no geographical pattern was evident. Disease and treatment type were not associated with differences in anti-JCV antibody status.


Assuntos
Anticorpos Anti-Idiotípicos/sangue , Vírus JC/imunologia , Leucoencefalopatia Multifocal Progressiva/epidemiologia , Esclerose Múltipla/epidemiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos Transversais , Feminino , Humanos , Leucoencefalopatia Multifocal Progressiva/sangue , Leucoencefalopatia Multifocal Progressiva/imunologia , Masculino , Pessoa de Meia-Idade , Esclerose Múltipla/sangue , Esclerose Múltipla/imunologia , Estudos Soroepidemiológicos , Adulto Jovem
3.
Neurochem Res ; 38(4): 876-85, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23397286

RESUMO

This study investigated the effects of combined supplementation with vitamin E and C against oxidative stress (OS) caused by intermittent cold exposure (ICE) in the hypothalamus (HY) of aging male Wistar rats [adult (3-months), middle-aged (18-months) and old (24-months)]. Each age was divided into sub-groups: control (CON), cold-exposed at 10 °C (C10), cold-exposed at 5 °C (C5), supplemented control (CON+S) and supplemented cold-exposed at either 5 °C (C5+S) or 10 °C (C10+S). The supplement was a daily dose of 400 mg vitamin C and 50 IU of vitamin E/kg body weight. Cold exposure lasted 2 h/day for 4 weeks. All age groups exposed to cold showed increase in body mass and feeding efficiency. Feeding efficiency in the supplemented old group showed a statistically significant increase in the cold (p < 0.001). Age-related increases in levels of hydrogen peroxide (H2O2), protein carbonyl (PrC), advanced oxidation protein products and thiobarbituric acid reactive substances (TBARS) were further increased by cold in the HY. Cold reduced thiol(P-SH) levels and increased superoxide dismutase (SOD) and, catalase (CAT) activities as well as Hsp72 levels. However, supplementation lowered H2O2, PrC and TBARS with decreases in Hsp72 levels and in SOD and CAT activities. These changes were concomitant with elevations in P-SH, vitamin E and C levels. The results show that the OS caused by ICE in the HY and its subsequent protection following supplementation is related to the intensity of ICE as well as age of the animal. Immunohistochemical studies are underway to examine the findings on ICE-induced oxidative injury in the HY, and the prospects for vitamin E and C supplementation in the senescent.


Assuntos
Envelhecimento/efeitos dos fármacos , Ácido Ascórbico/farmacologia , Temperatura Baixa/efeitos adversos , Hipotálamo/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Vitamina E/farmacologia , Animais , Antioxidantes/farmacologia , Catalase/metabolismo , Peróxido de Hidrogênio , Masculino , Carbonilação Proteica , Ratos , Ratos Wistar , Superóxido Dismutase/metabolismo , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismo
4.
Methods Mol Biol ; 2343: 247-258, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34473328

RESUMO

A high global prevalence of diabetes and its implications on the heart in vivo and in vitro tools have been pursued to alleviate the complications of high glucose. This chapter oulines the methods used for maintaining H9C2 cardiomyoblasts in vitro and for stimulating hyperglycemic situation. In addition, we present a method to assess cellular GLUT-4 expression using qRT-PCR. This cellular model also allows us to examine the therapeutic approach of an antioxidant, Trolox, for upregulating GLUT-4 and uptake of glucose under hyperglycemic condition.


Assuntos
Antioxidantes , Diabetes Mellitus , Miocárdio , Reação em Cadeia da Polimerase , Antioxidantes/farmacologia , Cromanos/farmacologia , Glucose , Transportador de Glucose Tipo 4/análise , Humanos , Miocárdio/citologia , Reação em Cadeia da Polimerase/métodos
5.
Methods Mol Biol ; 2343: 259-270, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34473329

RESUMO

Type-2 diabetes, characterized by hyperglycemia causing various symptoms of metabolic disorders in the heart, kidneys, and brain, has many underlying molecular mechanisms leading to functional insufficiency of these organs. We describe protocols wherein we have optimized conditions for maintenance of hyperglycemic H9c2 cell lines and design to assess the effect of a water-soluble vitamin, Trolox, on the apoptotic pathway. Primarily, the design provides researchers to analyze apoptosis by flow cytometry.


Assuntos
Apoptose , Citometria de Fluxo , Hiperglicemia , Miócitos Cardíacos , Linhagem Celular , Humanos , Miocárdio/citologia
6.
Biogerontology ; 12(4): 283-92, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21359656

RESUMO

This study aims at determining the possible changes in intracellular calcium (Ca (i) (2+) ), plasma membrane calcium ATPase (PMCA) activity and phosphatidylserine (PS) along with glutathione (GSH) level in response to an oxidant challenge in vitro. Erythrocytes were isolated on Percoll and incubated with 2, 2'azobis (2-aminopropane) hydrochloride (AAPH) as well as with vitamin C preceding AAPH incubation. Membrane integrity in terms of hemolysis was negatively related to acetylcholine esterase (AChE) activity with the extent of reduction under OS being higher in the old erythrocyte than in the young. A divergent pattern was seen towards lower PMCA and higher (Ca (i) (2+) ) in the young and old cells. However, the PMCA activity in the stressed young cell was high when pre-treated with vitamin C. PS externalization in the young under OS is perhaps analogous to normal aging, with vitamin C preventing premature death. These findings suggest that young erythrocytes may benefit from vitamin C in therapies addressed towards the mechanisms underlying the reduced effects of OS.


Assuntos
Envelhecimento Eritrocítico/efeitos dos fármacos , Peróxidos/toxicidade , Acetilcolinesterase/sangue , Animais , Ácido Ascórbico/sangue , Cálcio/sangue , Envelhecimento Eritrocítico/fisiologia , Eritrócitos/efeitos dos fármacos , Eritrócitos/metabolismo , Glutationa/sangue , Técnicas In Vitro , Masculino , Fragilidade Osmótica/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Fosfatidilserinas/sangue , ATPases Transportadoras de Cálcio da Membrana Plasmática/sangue , Ratos , Ratos Wistar
7.
Biologicals ; 39(2): 100-9, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21353596

RESUMO

Therapeutic proteins provide innovative and effective therapies for numerous diseases. However, some of these products are associated with unwanted immunogenicity that may lead to clinical consequences such as reduced or loss of efficacy, altered pharmacokinetics (PK), general immune and hypersensitivity reactions, and neutralisation of the natural counterpart (e.g. the physiological hormone). Regulatory guidance on immunogenicity assessment needs to take into consideration a great diversity of products, indications and patient populations as well as constantly advancing manufacturing technologies. Such guidance needs to be sufficiently specific while, at the same time, allowing interactive discussion and adjusted benefit-risk weighing of each product on a case-by-case basis, e.g. for a unique treatment of a life threatening disease acceptable treatment risks may differ considerably from the ones in case of less serious disease. This theme was the focus of the international conference "Taking immunogenicity assessment of therapeutic proteins to the next level", held at the Paul-Ehrlich-Institut in Langen, Germany, on the 10-11. June 2010. The objectives of the conference were to highlight how the field could move from that of a mere description of risk factors to a system of risk assessment and mitigation, as well as an understanding of the impact of unwanted immunogenicity on the overall benefit/risk consideration for a medicinal product. More than 150 experts from industry, academia and regulatory authorities worldwide discussed the phenomenon of undesired immunogenicity from different perspectives. The conference focussed on issues relevant to three areas: (1) new European guidelines that are currently the subject of discussion; (2) testing strategies for immunogenicity assessment; and (3) scientific progress on the product-related factors that may contribute to the development of pathogenesis of immunogenicity, in particular in the field of protein aggregation and post-translational modifications. This report provides an overview of issues, insights, and conclusions that were discussed and achieved during the meeting.


Assuntos
Produtos Biológicos/efeitos adversos , Produtos Biológicos/imunologia , Avaliação de Medicamentos/tendências , Hipersensibilidade a Drogas/diagnóstico , Proteínas/efeitos adversos , Proteínas/imunologia , Algoritmos , Animais , Formação de Anticorpos/fisiologia , Congressos como Assunto , Avaliação de Medicamentos/legislação & jurisprudência , Avaliação de Medicamentos/métodos , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Guias como Assunto , Humanos , Imunidade Inata/efeitos dos fármacos , Legislação de Medicamentos , Modelos Biológicos , Processamento de Proteína Pós-Traducional
8.
J Exp Med ; 177(2): 351-8, 1993 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-8381154

RESUMO

Superantigens (SAGs) represent a new class of antigens, characterized as T cell receptor (TCR) V beta-reactive elements. Bacterial toxins constitute the major group of exogenous SAGs, while the mouse mammary tumor virus (MMTV)-encoded Mls molecules represent the endogenous SAGs. Mls-1 is the prototype of the latter SAGs, because it elicits a very potent T cell stimulatory response in vitro in unprimed T cells expressing the TCR V beta 6 or 8.1 chains. In vivo, Mls-1 causes deletion of immature T cells bearing the V beta 6, 7, 8.1, or 9 chains. Although Mls-1 was functionally discovered > 20 yr ago, it has not been possible to raise antibodies against this molecule. We have previously cloned and sequenced the Mtv-7 sag gene, which encodes Mls-1. Sequence comparisons with other MMTV sag genes suggested that the polymorphic 3' end encodes the TCR V beta specificity of these SAGs. We have, therefore, immunized hamsters with a 14-amino acid peptide from the deduced COOH-terminal sequence of the Mtv-7 sag gene. We describe here the production of a monoclonal antibody (mAb), 3B12, which is peptide specific and reacts with a recombinant baculovirus product of Mtv-7 sag. This mAb blocks Mls-1-specific T cell recognition and detects the Mls-1 protein on the surface of the B cell hybridoma LBB.A, but not on LBB.11, which is an Mtv-7 loss variant of LBB.A. Transfection of the Mtv-7 sag gene into LBB.11 renders this cell functionally Mls-1+ as well as positive for 3B12 binding, confirming the specificity of this mAb. It is well documented that B cells and CD8+ T cells express T cell stimulatory Mls-1 determinants, and we show here that this functional profile correlates with the expression of MMTV-specific mRNA. However, primary lymphocytes derived from Mls-1+ mice do not stain with 3B12, even after in vitro activation with mitogens or phorbol ester.


Assuntos
Anticorpos Monoclonais/imunologia , Antígenos Virais/imunologia , Vírus do Tumor Mamário do Camundongo/imunologia , Antígenos Secundários de Estimulação de Linfócitos/imunologia , Sequência de Aminoácidos , Animais , Sequência de Bases , Cricetinae , Expressão Gênica , Genes Virais , Vírus do Tumor Mamário do Camundongo/genética , Camundongos , Camundongos Endogâmicos DBA , Dados de Sequência Molecular , Oligodesoxirribonucleotídeos/química , Peptídeos/química , Peptídeos/imunologia , RNA Viral/genética , Proteínas Recombinantes/imunologia , Sequências Repetitivas de Ácido Nucleico , Proteínas Estruturais Virais/genética
9.
J Exp Med ; 177(6): 1735-43, 1993 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-8388432

RESUMO

Mouse mammary tumor virus (MMTV)-encoded superantigens (SAGs) influence the murine T cell repertoire and stimulate a strong mixed lymphocyte response in vitro. These SAGs are encoded by the open reading frame of the 3' long terminal repeat of MMTV, termed MMTV SAGs. The T cell response to MMTV SAGs is V beta restricted and requires expression of the class II molecules of the major histocompatibility complex (MHC) on the presenting cells. While human T cells respond to bacterial SAGs, it is not known if human T cells or human MHC class II molecules can interact with MMTV SAGs. A fibroblastic cell line expressing the human MHC class II molecule HLA-DR1 and the Mtv-7 sag gene encoding Mls-1 was used to stimulate human T cells. We show here that human T cells efficiently proliferate in response to Mls-1 presented by HLA-DR1. This T cell response was inhibited by mAbs directed against CD4 or MHC class II molecules but not by mAbs specific for CD8 or MHC class I molecules. Moreover, the response to Mls-1 was limited to human T cells expressing a restricted set of T cell receptor V beta chains. Human T cells expressing V beta 12, 13, 14, 15, and 23 were selectively amplified after Mtv-7 sag stimulation. Interestingly, these human V beta s share the highest degree of homology with the mouse V beta s interacting with Mls-1. These results show a strong evolutionary conservation of the structures required for the presentation and the response to retrovirally encoded endogenous SAGs, raising the possibility that similar elements operate in humans to shape the T cell repertoire.


Assuntos
Antígenos Virais/imunologia , Vírus do Tumor Mamário do Camundongo/imunologia , Receptores de Antígenos de Linfócitos T alfa-beta/fisiologia , Linfócitos T/imunologia , Animais , Sequência de Bases , Evolução Biológica , Antígenos CD4/fisiologia , Antígenos CD8/fisiologia , Antígenos HLA-DR/análise , Antígenos HLA-DR/fisiologia , Humanos , Camundongos , Antígenos Secundários de Estimulação de Linfócitos/análise , Dados de Sequência Molecular , Reação em Cadeia da Polimerase , Polimorfismo Genético , Ratos , Receptores de Antígenos de Linfócitos T alfa-beta/genética
10.
Biogerontology ; 10(1): 53-63, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18560990

RESUMO

In this study, we have assessed the impact of vitamin E and exercise on acquisition and retention of spatial memory for a given task in aging rats, using a T-maze. Acetylcholine esterase (AChE) and cholineacetyl transferase (ChAT) activities and acetylcholine (ACh) were measured in the cerebral cortex (CC) of male Wistar rats of 4- (adult), 12- (middle-aged) and 18-months (old) of age. Animals were categorized into sedentary [(SEC (N)], sedentary supplemented [SEC (+E)], swim trained [SWT (N)] and swim trained supplemented [SWT (+E)]. In the old, ChAT activity increased in the SEC (+E). AChE activity was highest in the adults, irrespective of training or supplementation. By contrast, ACh concentration remained unaltered with age, exercise and supplementation. Middle-aged and old rats were benefited in terms of a better acquisition and retention in the case of those that were trained and supplemented with Vitamin E. Adults showed better retention in all the groups after 7 and 15 days, while in the middle-aged, training was beneficial after 15 days. We observed decreased AChE activity when old rats were trained with the supplement. Our results also suggest that this regimen may be analogous to the AChE inhibitors that are widely advocated to derive positive benefits in up-regulating the possible reduction in ACh and in turn age-associated memory deficits.


Assuntos
Acetilcolina/metabolismo , Envelhecimento/metabolismo , Antioxidantes/farmacologia , Córtex Cerebral/efeitos dos fármacos , Fibras Colinérgicas/efeitos dos fármacos , Nootrópicos/farmacologia , Esforço Físico , Vitamina E/farmacologia , Acetilcolinesterase/metabolismo , Fatores Etários , Animais , Córtex Cerebral/metabolismo , Colina O-Acetiltransferase/metabolismo , Fibras Colinérgicas/metabolismo , Aprendizagem/efeitos dos fármacos , Masculino , Rememoração Mental/efeitos dos fármacos , Nootrópicos/sangue , Ratos , Ratos Wistar , Natação , Vitamina E/sangue
11.
Biogerontology ; 10(6): 659-69, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19214770

RESUMO

The effects of oxidative stress (OS) on the rat erythrocytes (RBCs) that were fractionated on the percoll/BSA gradient into young and old cells were studied to find out if the altered Na+/H+ and Cl⁻/ HCO3⁻ antiporters and in turn the intracellular pH (pHi) could act as one of the promoters of cell death. Old cells were more spherical with lesser surface area, more fragile osmotically and had lesser protein sulphydryl content than the young cells. OS was induced in RBCs by 2,20-azobis (2-amidinopropane) dihydrochloride (AAPH). AAPH increased the superoxide dismutase (SOD) activity and MDA level and, the changes between the young and old. Interestingly, vitamin C was effective in reducing MDA in the old. Further, in the old a rapid Na+-dependent acidification in the presence of AAPH and a marginal acidosis in the presence of vitamin C were evident. Old RBCs exhibited higher acidosis and vitamin C was less effective in lowering the stress-induced acidosis compared to the young. Our studies suggest that increased acidosis followed by low intracellular pH could be one of the determinant factors for the disappearance of old RBCs from circulation, and perhaps of the young too under OS.


Assuntos
Senescência Celular , Eritrócitos/metabolismo , Estresse Oxidativo , Amidinas/farmacologia , Análise de Variância , Animais , Antioxidantes/farmacologia , Ácido Ascórbico/farmacologia , Antiportadores de Cloreto-Bicarbonato/sangue , Eritrócitos/efeitos dos fármacos , Concentração de Íons de Hidrogênio , Peroxidação de Lipídeos , Masculino , Malondialdeído/sangue , Fragilidade Osmótica , Oxidantes/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Ratos , Trocadores de Sódio-Hidrogênio/sangue , Superóxido Dismutase/sangue
12.
Acta Crystallogr Sect E Struct Rep Online ; 64(Pt 2): o362, 2008 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-21201394

RESUMO

The asymmetric unit of the title compound, C(14)H(10)Br(2)N(6)O, contains two crystallographically independent mol-ecules. The pyrazole ring of one mol-ecule makes dihedral angles of 22.0 (3) and 3.5 (3)° with the pyrimidine and benzene rings, respectively; the corresponding values in the other mol-ecule are 9.2 (3) and 2.1 (3)°, respectively. The mol-ecules are linked by N-H⋯O, C-H⋯N and C-H⋯Br hydrogen bonds.

13.
Acta Crystallogr Sect E Struct Rep Online ; 64(Pt 5): o818, 2008 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-21202308

RESUMO

In the title mol-ecule, C(15)H(17)NO, the cyclo-hexane ring adopts a chair conformation. The cyano and methyl groups at position 1 have axial and equatorial orientations, respectively. The benzene ring has an equatorial orientation. A C-H⋯π inter-action involving the benzene ring is found in the crystal structure.

14.
Acta Crystallogr Sect E Struct Rep Online ; 64(Pt 6): o1006, 2008 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-21202532

RESUMO

In the title mol-ecule, C(14)H(14)ClNO, the cyclo-hexane ring adopts a chair conformation. The cyano group and the methyl group have axial and equatorial orientations, respectively. The benzene ring has an equatorial orientation. A C-H⋯π inter-action involving the benzene ring is found in the crystal structure.

15.
Acta Crystallogr Sect E Struct Rep Online ; 64(Pt 6): o1020, 2008 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-21202545

RESUMO

In the title mol-ecule, C(19)H(18)O(2), the cyclo-hexene ring adopts an envelope conformation, with all substituents equatorial. The dihedral angle between the benzene and phenyl rings is 83.75 (16)°. No classical hydrogen bonds are found in the crystal structure.

16.
Acta Crystallogr Sect E Struct Rep Online ; 64(Pt 6): o1066, 2008 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-21202585

RESUMO

In the title mol-ecule, C(14)H(16)O, the cyclo-hexene ring adopts an envelope conformation, with all substituents equatorial. Mol-ecules are linked by C-H⋯O hydrogen bonds. A C-H⋯π inter-action involving the benzene ring is also found in the crystal structure. The H atoms of both methyl groups are disordered equally over two positions.

17.
Acta Crystallogr Sect E Struct Rep Online ; 64(Pt 7): o1263, 2008 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-21202897

RESUMO

In the title mol-ecule, C(16)H(14)OS, the dihedral angle between the phenyl and benzene rings is 3.81 (15)°. The H atoms of the central enone group are trans. The propenone unit makes dihedral angles of 11.73 (18) and 11.62 (17)° with the benzene and phenyl rings, respectively. The crystal structure is stabilized by weak C-H⋯O and C-H⋯π inter-actions.

18.
Toxicol In Vitro ; 21(8): 1355-64, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17714909

RESUMO

The present study was designed to induce oxidative stress in lipid and aqueous phases through azo bis(2-amidinopropane)dihydrochloride (AAPH), 2,2'-azobis 2,4-dimethylvaleronitrile (ADVN) and hydrogen peroxide (H(2)O(2)) either alone or in combination with vitamin C or vitamin El and to assess the vulnerability of rat erythrocytes to oxidative stress. While AAPH acted equally on cell membrane and cytosol, ADVN increased OS in the membrane. The extent of hemolysis and increased membrane fragility caused was more in the case of azo compounds than of H(2)O(2). While vitamin E (2mM) reduced oxidative stress in the membrane, vitamin C (60mM) was more effective in the lysates. The concentration of malondialdehyde and advanced oxidation protein products was lowered by antioxidants. The level of lipofuscin, a product of lipid peroxidation was also increased by ADVN and H(2)O(2). Antioxidants, did, however, reduce the accumulation of protein carbonyl content in cells exposed to azo compounds although they were ineffective in inhibiting oxidation of membrane band 3 protein and sulphydryl content. Taken together, our study demonstrated the antioxidative property of vitamin E and vitamin C in reducing oxidative stress in aqueous as well as lipid phases of erythrocytes and further suggested the feasibility of in vitro models in evaluating the mechanisms of oxidative injury.


Assuntos
Antioxidantes/farmacologia , Suplementos Nutricionais , Eritrócitos/efeitos dos fármacos , Eritrócitos/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Animais , Modelos Biológicos , Ratos
19.
Acta Crystallogr Sect E Struct Rep Online ; 64(Pt 1): o60, 2007 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-21200937

RESUMO

In the title mol-ecule, C(16)H(11)Cl(3)O, the dihedral angle between the two benzene rings is 33.2 (1)°. The crystal packing is stabilized by C-H⋯O hydrogen bonds.

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