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1.
Theriogenology ; 99: 111-118, 2017 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-28708491

RESUMO

There has been a growing interest in the role played by antioxidant enzymes in the regulation of endometrial function in mammals. However, little is known about enzymatic antioxidative pathways involved in conditioning the cyclic and early pregnant endometrium for conceptus attachment and implantation in domestic ruminants. We aimed to investigate changes in activities of superoxide dismutase 1 and 2 (SOD1, SOD2), glutathione peroxidase (GPX), glutathione reductase (GR) and catalase (CAT) in sheep caruncles (CAR) and intercaruncles (ICAR) endometrial tissues of cyclic and early pregnant ewes. Irrespective of day of cycle or pregnancy, CAR demonstrated higher activities of SOD1 and SOD2 than in ICAR. On day 12 of the estrous cycle, ICAR demonstrated higher activity of GPX and GR than in CAR tissues. On days 12 and 16 the estrous cycle, ICAR demonstrated higher activity of CAT than in CAR. CAR demonstrated higher activity of GPX on day 18 than on days 4, 8, 12 and 16 of the estrous cycle. CAR demonstrated higher activity of CAT on day 18 than on days 4, 8, 12 and 16 of the estrous cycle. ICAR demonstrated higher activity of CAT on day 18 than on days 4, 8, and 16 of the estrous cycle. The activity of CAT in ICAR increased from days 4 and 8 to day 12 of the estrous cycle. The activity of SOD2 in CAR increased from day 16 to day 18 of pregnancy. On day 12 of pregnancy, CAR demonstrated higher activity of GPX than in ICAR. On day 16 of pregnancy, ICAR demonstrated higher activity of GPX than in CAR. The activity of GPX in ICAR increased from day 12 to day 16 of pregnancy. The activity of GPX in CAR increased from day 16 to day 18 of pregnancy. The activity of GR in CAR and ICAR increased from days 12 and 16 to day 18 of pregnancy. On days 16 and 18 of pregnancy, ICAR demonstrated higher activity of CAT than in CAR. The activity of CAT in CAR decreased from day 12 to days 16 and 18 of pregnancy. The activity of CAT in ICAR decreased from day 12 to day 16 of pregnancy and then increased from day 16 to day 18 of pregnancy. In conclusion, different antioxidant mechanisms operate within CAR and ICAR endometrium throughout the estrous cycle and during early pregnancy. This might be related to the different but important roles of CAR and ICAR endometrial tissues for the establishment of pregnancy.


Assuntos
Endométrio/metabolismo , Enzimas/metabolismo , Prenhez , Ovinos/fisiologia , Animais , Feminino , Regulação Enzimológica da Expressão Gênica , Estresse Oxidativo , Gravidez , Prenhez/fisiologia
2.
Int J Biochem Cell Biol ; 60: 112-8, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25578560

RESUMO

Conceptus-derived paracrine signals play crucial roles in the preparation of a uterine environment capable of supporting implantation and development of the conceptus. However, little is known about the regulation of endometrial tryptophanyl tRNA synthetase (WARS) and manganese superoxide dismutase (SOD2) protein expression by the implanting and post-implanting conceptus. We hypothesized that the conceptus-derived signals favourably influences uterine environment for implantation through regulation of WARS and SOD2 expression in ovine caruncular endometrium. To test this hypothesis, WARS and SOD2 protein and mRNA expression was determined in caruncular endometrial tissues of unilaterally pregnant ewes at implantation (day 16) and post-implantation (day 20) periods. WARS protein expression increased in caruncular tissues of the gravid uterine horns compared with the non-gravid uterine horns on days 16 and 20 of pregnancy. There were no changes in SOD2 protein expression between the gravid and non-gravid uterine horns, irrespective of the day of pregnancy. On day 16 of pregnancy, there were no differences in WARS and SOD2 mRNA expression between the gravid and non-gravid uterine horns but expression of both genes was higher in the gravid uterine horns when compared with the non-gravid uterine horns on day 20 of pregnancy. In conclusion, the use of the unilaterally pregnant ewe model provides for the first time firm evidence that the early implantation and post-implanting conceptus-derived signals up-regulate WARS protein expression within the caruncular endometrium. Further studies are necessary to identify these signalling molecules and to understand mechanisms whereby they exert paracrine action within the endometrium.


Assuntos
Endométrio/enzimologia , Superóxido Dismutase/metabolismo , Triptofano-tRNA Ligase/metabolismo , Animais , Implantação do Embrião/fisiologia , Endométrio/metabolismo , Feminino , Gravidez , Ovinos , Superóxido Dismutase/genética , Triptofano-tRNA Ligase/genética , Útero/enzimologia , Útero/metabolismo
3.
Free Radic Res ; 48(12): 1505-13, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25263566

RESUMO

Oxidative stress is associated with decreased female fertility and adversely affects prenatal development. Mammalian cells have developed a network of enzymatic and non-enzymatic antioxidant defence systems to prevent oxidative stress. Little attention has been paid to the antioxidative pathways in placentas of normal and disturbed pregnancies, leaving a gap in our knowledge about the role of antioxidants in the control of foeto-placental development. The challenges in studying early human pregnancy can partly be overcome by designing animal models of abnormal pregnancy. We aimed to determine whether the antioxidant status of placentas from the CBA/J × DBA/2 abortion-prone pregnant mice differed from that of normal pregnant mice. The foetal/placental weight ratio was lower in abortion-prone matings compared with that in non-abortion-prone matings. The increased placental malondialdehyde (MDA) content, the end products of lipid peroxidation, with concomitants alterations in placental antioxidants, namely copper-zinc containing superoxide dismutase (SOD1), manganese containing (SOD2), glutathione peroxidases (GPX), glutathione reductase (GR) and catalase (CAT) activities may be involved in placental and foetal growth restriction. We show that placental oxidative stress is linked with poor prenatal development and pregnancy losses in CBA/J × DBA/2 mice matings. This animal model may be useful in the evaluation of nutritional antioxidant therapies for oxidative stress and associated prenatal developmental disorders.


Assuntos
Aborto Espontâneo/metabolismo , Antioxidantes/metabolismo , Desenvolvimento Fetal , Placenta/metabolismo , Placentação , Animais , Feminino , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos CBA , Camundongos Endogâmicos DBA , Gravidez
4.
Reproduction ; 147(5): 599-614, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24446454

RESUMO

The expression and regulation of endometrial proteins are crucial for conceptus implantation and development. However, little is known about site-specific proteome profiles of the mammalian endometrium during the peri-implantation period. We utilised a two-dimensional gel electrophoresis/mass spectrometry-based proteomics approach to compare and identify differentially expressed proteins in sheep endometrium. Caruncular and intercaruncular endometrium were collected on days 12 (C12) and 16 (C16) of the oestrous cycle and at three stages of pregnancy corresponding to conceptus pre-attachment (P12), implantation (P16) and post-implantation (P20). Abundance and localisation changes in differentially expressed proteins were determined by western blot and immunohistochemistry. In caruncular endometrium, 45 protein spots (5% of total spots) altered between day 12 of pregnancy (P12) and P16 while 85 protein spots (10% of total spots) were differentially expressed between P16 and C16. In intercaruncular endometrium, 31 protein spots (2% of total spots) were different between P12 and P16 while 44 protein spots (4% of total spots) showed differential expression between C12 and C16. The pattern of protein changes between caruncle and intercaruncle sites was markedly different. Among the protein spots with implantation-related changes in volume, 11 proteins in the caruncular endometrium and six proteins in the intercaruncular endometrium, with different functions such as protein synthesis and degradation, antioxidant defence, cell structural integrity, adhesion and signal transduction, were identified. Our findings highlight the different but important roles of the caruncular and intercaruncular proteins during early pregnancy.


Assuntos
Endométrio/fisiologia , Proteínas da Gravidez/fisiologia , Prenhez/fisiologia , Proteômica , Ovinos/fisiologia , Animais , Eletroforese em Gel Bidimensional , Desenvolvimento Embrionário/fisiologia , Estro/fisiologia , Feminino , Espectrometria de Massas , Gravidez , Transdução de Sinais/fisiologia
5.
Respir Physiol Neurobiol ; 180(2-3): 298-304, 2012 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-22210465

RESUMO

Obstructive sleep apnea (OSA) and metabolic syndrome (MetS) are associated with increased cardiovascular morbidity and mortality. Increased homocysteine is suggested as an independent risk factor for atherosclerosis and cardiovascular disease but remains disputed in OSA. We assessed polysomnography, carotid intima-media thickness (CIMT) and biology in 35 MetS patients, according to the presence (OSA+MetS; n=26) or the absence of OSA (MetS; n=9). In OSA+MetS patients, homocysteine levels were increased compared to MetS subjects (12.8 ± 3.8 vs. 9.5 ± 2.5 µmol/L; P=0.026). In the whole population, homocysteine correlated with apnea-hypopnea index (AHI) (r=0.522; P=0.001) and CIMT (r=0.376; P=0.026). Homocysteine was negatively correlated with plasma thiols (r=-0.406; P=0.017) and positively with urinary 15-F2t-isoprostanes (r=0.347; P=0.044). Multivariate regression analysis revealed that AHI (ß=0.559; P<0.001) and urinary 15-F2t-isoprostane (ß=0.310; P=0.018) were independently associated with homocysteine level. We conclude that homocysteine level was higher in MetS when associated with OSA and proportional to OSA severity. In this context, vascular remodeling appeared more severe and mediated by oxidative stress.


Assuntos
Artérias Carótidas/patologia , Homocisteína/metabolismo , Síndrome Metabólica/patologia , Apneia Obstrutiva do Sono/patologia , Antioxidantes/metabolismo , Nível de Alerta/fisiologia , Aterosclerose/complicações , Aterosclerose/metabolismo , Pressão Sanguínea/fisiologia , Artérias Carótidas/diagnóstico por imagem , Espessura Intima-Media Carotídea , Cromatografia Líquida de Alta Pressão , Dinoprosta/análogos & derivados , Endotélio Vascular/fisiologia , Feminino , Humanos , Isoprostanos/urina , Lipídeos/sangue , Masculino , Síndrome Metabólica/complicações , Pessoa de Meia-Idade , Oxirredução , Estresse Oxidativo/fisiologia , Polissonografia , Apneia Obstrutiva do Sono/etiologia , Apneia Obstrutiva do Sono/metabolismo , Compostos de Sulfidrila/sangue , Espectrometria de Massas em Tandem
6.
Hum Exp Toxicol ; 21(12): 635-41, 2002 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-12540033

RESUMO

Quinolones (Qs) were shown to have cytotoxic effects in various cell lines including human carcinoma cells; however, mechanism of these effects was not fully understood. To investigate the possibility of the involvement of an oxidative stress induction in this mechanism of action, we examined viability of human fibroblast cells exposed to a Q antibiotic, ciprofloxacin (CPFX), and measured lipid peroxidation and total glutathione (GSH) levels, and activities of catalase (Cat), superoxide dismutases (SODs), glutathione peroxidase (GPx). The effects of vitamin E pretreatment on those parameters were also examined. Our results showed that the effect of CPFX on the viability of the cells, as determined by neutral red uptake assay, was time dependent. Cytotoxicity was not observed in the concentration range of 0.0129-0.387 mM CPFX when the cells were incubated for 24 hours. However, significant level of cytotoxicity was observed at concentrations 0.129 and 0.194 mM, and >0.129 mM, following 48 and 72 hours of exposure, respectively. When the cells were exposed to 0.194 mM CPFX for 48 hours, the level of lipid peroxidation increased and the content of total GSH decreased significantly; activities of total SOD, Mn SOD and CuZn SOD did not change; the decrease observed in the activity of Cat was not significant; and the activity of GPx was highly variable. Vitamin E pretreatment of the cells provided significant protection against CPFX-induced cytotoxicity; lowered the level of lipid peroxidation significantly, but increased the total GSH content only moderately; no change was observed in the activities of Cat and total SOD, but a significant increase in Mn SOD and a significant decrease in CuZn SOD were noticed. These results suggested that CPFX-induced cytotoxicity on human fibroblast cell cultures is related to oxidative stress, and vitamin E pretreatment can afford a protection.


Assuntos
Anti-Infecciosos/toxicidade , Antioxidantes/farmacologia , Ciprofloxacina/toxicidade , Fibroblastos/efeitos dos fármacos , Vitamina E/farmacologia , Adulto , Catalase/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Relação Dose-Resposta a Droga , Antagonismo de Drogas , Fibroblastos/metabolismo , Fibroblastos/patologia , Glutationa/metabolismo , Glutationa Peroxidase/metabolismo , Humanos , Peroxidação de Lipídeos , Estresse Oxidativo , Pele/efeitos dos fármacos , Pele/patologia , Superóxido Dismutase/metabolismo
7.
Artigo em Inglês | MEDLINE | ID: mdl-11465936

RESUMO

INTRODUCTION: Increasing evidence suggests that oxidative stress may be involved in the pathogenesis of amyotrophic lateral sclerosis (ALS). The antioxidant vitamin E (alpha-tocopherol) has been shown to slow down the onset and progression of paralysis in transgenic mice expressing a mutation in superoxide dismutase found in certain forms of familial ALS. The current study was designed to determine whether alpha-tocopherol (500 mg b.i.d.) may be efficacious in the treatment of ALS. METHODS: Two hundred and eighty-nine patients with ALS of less than 5 years duration, treated with riluzole, were enrolled in this study, and were randomly assigned to receive either alpha-tocopherol or placebo daily for one year. The primary outcome measure was the rate of deterioration of function assessed by the modified Norris limb scale. Patients were assessed at entry, and every 3 months thereafter during the study period. Survival was also recorded. Biochemical markers of oxidative stress were measured in a subset of patients on entry and after 3 months of treatment. RESULTS: After 12 months of treatment, alpha-tocopherol had no effect on the primary outcome measure. Survival was not influenced by treatment. Among secondary outcome measures, patients given alpha-tocopherol were less likely to progress from the milder state A to the more severe state B (P=0.046) of the ALS Health State scale. After 3 months treatment, analysis of oxidative stress markers showed an increase in glutathione peroxidase activity in plasma (P = 0.0389) and a decrease in plasma levels of thiobarbituric acid reactive species (P = 0.0055) in the group of patients given alpha-tocopherol in combination with riluzole. CONCLUSION: Although alpha-tocopherol did not appear to affect the survival and motor function in ALS, patients receiving riluzole plus alpha-tocopherol remained longer in the milder states of the ALS Health State scale and showed, after 3 months, changes in biochemical markers of oxidative stress. Further studies are required to confirm the greater sensitivity of the ALS Health State scale over other clinical endpoints.


Assuntos
Doença dos Neurônios Motores/tratamento farmacológico , Vitamina E/efeitos adversos , Idoso , Método Duplo-Cego , Feminino , Seguimentos , Glutationa Peroxidase/sangue , Humanos , Masculino , Pessoa de Meia-Idade , Doença dos Neurônios Motores/diagnóstico , Doença dos Neurônios Motores/enzimologia , Exame Neurológico/efeitos dos fármacos , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismo , Resultado do Tratamento
8.
Talanta ; 55(2): 291-6, 2001 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-18968372

RESUMO

Recently, we hypothesized that DNA separation mechanisms in slalom chromatography (SC) and packed column hydrodynamic chromatography (HDC) could be connected and simultaneously observed 'J. Chromatogr. A 886 (2000) 1'. The present paper describes the migration of various circular and linear double-stranded DNAs in a chromatographic system using a C1 stationary phase and an acetonitrile-phosphate buffer mixture as a mobile phase. The migration dependence on the flow rate for the different species showed the relative contribution of both the SC and HDC separation mechanisms. A transition between the SC and HDC regimes was demonstrated for the first time. In addition, the data were analyzed in terms of polymer migration in a dense structure. Three different behaviors were distinguished in relation to the size and the compactness of the nucleic acid.

9.
J Chromatogr A ; 886(1-2): 1-7, 2000 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-10950270

RESUMO

Slalom chromatography (SC) is an alternative chromatographic procedure for the separation of relatively large double-stranded DNA molecules and is based on a new principle. The retardation of the DNA fragments from the cleavage of the Lambda DNA by the KpnI restriction enzyme was studied using an acetonitrile-phosphate buffer as a mobile phase with various concentrations of viscosity modifier (i.e. glycerol) and a C1 column as a stationary phase. The DNA molecule retention was accurately described over the glycerol concentration range using a model previously established. It was shown that the eluent viscosity increase enhanced the slalom chromatographic capacity to separate the DNA fragments. A connection between SC and 'hydrodynamic chromatography' processes was predicted to link the two processes in a global separation mechanism based on a non-equilibrium principle.


Assuntos
Cromatografia Líquida/métodos , DNA/isolamento & purificação
10.
Talanta ; 52(6): 1105-10, 2000 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-18968072

RESUMO

Slalom chromatography is an alternative chromatographic procedure for the analysis of relatively large double-stranded DNA molecules and is based on a hydrodynamic principle. The retardation of the DNA fragments from the cleavage of the Lambda DNA by the KpnI restriction enzyme was studied using an acetonitrile-phosphate buffer as a mobile phase (flow rate equal to 0.3 ml/min) and a C1 column as a stationary phase at various temperatures. It was shown that the temperature constituted an important parameter for the separation of the DNA fragments in slalom chromatography. The DNA hydrodynamic behavior with the temperature was related to the variation in the fluid viscosity and the modification of the elastic properties of the biopolyrner.

12.
Laryngorhinootologie ; 71(6): 319-22, 1992 Jun.
Artigo em Alemão | MEDLINE | ID: mdl-1637454

RESUMO

The authors consider the possibility of routine use of evoked otoacoustic emissions (EOE) in diagnosis of sensory hearing loss by comparison of EOE curves with relative curves obtained by pure tone audiometry. 180 ears with sensory hearing loss of different aetiologies were examined. EOE were obtained by application of Bray and Kemp's Evoked Otoacustic Measurement Package (ILO88). The results obtained show a close correlation between presence of EOE and real hearing losses of different frequencies obtained by pure tone audiometric evaluation. We could detect no EOE with hearing losses over 50 dB HL at 500 Hz, 40 dB HL at 1000 Hz, 50 dB HL at 2000 Hz and 85 dB HL at 4000 Hz. With a rate of middle hearing loss over 45 dB HL we also did not find EOE for the whole frequency range. On the base of this study, the authors conclude that EOE explore the functional integrity of those parts of the cochlea that correspond to the middle frequencies of hearing range. If EOE are not detectable, statements on the nature and extent of hearing loss on the base of this examination are not valid.


Assuntos
Potenciais Microfônicos da Cóclea/fisiologia , Perda Auditiva Neurossensorial/diagnóstico , Adolescente , Adulto , Idoso , Limiar Auditivo/fisiologia , Criança , Nervo Coclear/fisiopatologia , Feminino , Perda Auditiva Neurossensorial/fisiopatologia , Humanos , Masculino , Microcomputadores , Pessoa de Meia-Idade , Processamento de Sinais Assistido por Computador/instrumentação
13.
HNO ; 40(1): 16-8, 1992 Jan.
Artigo em Alemão | MEDLINE | ID: mdl-1568879

RESUMO

132 patients with chronic maxillary sinusitis were included in this bacteriological study of the intrasinus exudate obtained by a radical antrostomy or antral puncture. We found 78.3% aerobes, 21.7% anaerobes, 51.5% gram positive and 48.5% gram negative micro-organisms, but no fungi in 120 cultures. The commonest aerobic species was Haemophylus (20%), whereas Peptococcus and Bacteroides were the commonest anaerobes (10%).


Assuntos
Infecções Bacterianas/microbiologia , Sinusite Maxilar/microbiologia , Adolescente , Adulto , Bactérias/isolamento & purificação , Técnicas Bacteriológicas , Doença Crônica , Feminino , Humanos , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade
14.
Laryngorhinootologie ; 70(8): 412-6, 1991 Aug.
Artigo em Alemão | MEDLINE | ID: mdl-1910377

RESUMO

The authors consider the problems of the early diagnosis of paediatric hypoacusis, presenting a study done on twenty audiological high risk children that were subjected to audiometric screening by delayed cochlear otoacoustic emissions (EOE) and brainstem auditory evoked potentials (BEAPs). Eighteen of twenty children that were examined were normal, while two had bilateral sensorineural hearing loss. EOE were evoked in all patients that presented normal BAEP thresholds, while they were absent in deaf subjects. Evoked otoacoustic emissions research allows us to identify two groups of subjects: those with normal EOE who can be considered normal hearing subjects, and those without EOE who may present a disturbed auditory system. Nevertheless, EOE testing does not allow us to judge the type of hearing loss. The time for EOE testing is approximately five minutes for each subject. On the grounds of their experience, the authors conclude that EOE testing represents a useful and reliable test which differentiates normal auditory function subjects from hypoacoustic ones. Compared to other techniques used in audiological paediatric diagnosis, such as reactometry, BOEL test and Crib. O. Gram, which present the possibility of false positive and false negative results, and BSERA, which even if reliable, must be limited to few selected audiological high-risk subjects, EOE is easy to implement and readily available. Major limitations of this technique seem to be the possibility of false positives, and the impossibility to specify localisation and type of the hearing loss by EOE only.


Assuntos
Potenciais Microfônicos da Cóclea , Potenciais Evocados Auditivos do Tronco Encefálico , Transtornos da Audição/diagnóstico , Transtornos da Audição/congênito , Transtornos da Audição/fisiopatologia , Humanos , Lactente
15.
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