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1.
Free Radic Biol Med ; 143: 331-340, 2019 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-31422078

RESUMO

The activation of the transcription factor Nrf2 and the consequent increment in the antioxidant response might be a powerful strategy to contend against reperfusion damage. In this study we compared the effectiveness between sulforaphane (SFN), a well known activator of Nrf2 and the mechanical maneuver of post-conditioning (PostC) to confer cardioprotection in an in vivo cardiac ischemia-reperfusion model. We also evaluated if additional mechanisms, besides Nrf2 activation contribute to cardioprotection. Our results showed that SFN exerts an enhanced protective response as compared to PostC. Bot, strategies preserved cardiac function, decreased infarct size, oxidative stress and inflammation, through common protective pathways; however, the aryl hydrocarbon receptor (AhR) also participated in the protection conferred by SFN. Our data suggest that SFN-mediated cardioprotection involves transient Nrf2 activation, followed by phase I enzymes upregulation at the end of reperfusion, as a long-term protection mechanism.


Assuntos
Anticarcinógenos/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Isotiocianatos/farmacologia , Traumatismo por Reperfusão Miocárdica/prevenção & controle , Fator 2 Relacionado a NF-E2/metabolismo , Estresse Oxidativo , Receptores de Hidrocarboneto Arílico/metabolismo , Animais , Masculino , Traumatismo por Reperfusão Miocárdica/metabolismo , Traumatismo por Reperfusão Miocárdica/patologia , Fator 2 Relacionado a NF-E2/genética , Estresse Nitrosativo , Substâncias Protetoras/farmacologia , Ratos Wistar , Receptores de Hidrocarboneto Arílico/genética , Transdução de Sinais , Sulfóxidos
2.
Free Radic Biol Med ; 129: 407-417, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30316780

RESUMO

Electron leakage from dysfunctional respiratory chain and consequent superoxide formation leads to mitochondrial and cell injury during ischemia and reperfusion (IR). In this work we evaluate if the supramolecular assembly of the respiratory complexes into supercomplexes (SCs) is associated with preserved energy efficiency and diminished oxidative stress in post-ischemic hearts treated with the antioxidant N-acetylcysteine (NAC) and the cardioprotective maneuver of Postconditioning (PostC). Hemodynamic variables, infarct size, oxidative stress markers, oxygen consumption and the activity/stability of SCs were compared between groups. We found that mitochondrial oxygen consumption and the activity of respiratory complexes are preserved in mitochondria from reperfused hearts treated with both NAC and PostC. Both treatments contribute to recover the activity of individual complexes. NAC reduced oxidative stress and maintained SCs assemblies containing Complex I, Complex III, Complex IV and the adapter protein SCAFI more effectively than PostC. On the other hand, the activities of CI, CIII and CIV associated to SCs assemblies were preserved by this maneuver, suggesting that the activation of other cardioprotective mechanisms besides oxidative stress contention might participate in maintaining the activity of the mitochondrial respiratory complexes in such superstructures. We conclude that both the monomeric and the SCs assembly of the respiratory chain contribute to the in vivo functionality of the mitochondria. However, although the ROS-induced damage and the consequent increased production of ROS affect the assembly of SCs, other levels of regulation as those induced by PostC, might participate in maintaining the activity of the respiratory complexes in such superstructures.


Assuntos
Acetilcisteína/farmacologia , Antioxidantes/farmacologia , Cardiotônicos/farmacologia , Mitocôndrias Cardíacas/efeitos dos fármacos , Traumatismo por Reperfusão Miocárdica/prevenção & controle , Animais , Transporte de Elétrons/efeitos dos fármacos , Complexo I de Transporte de Elétrons/genética , Complexo I de Transporte de Elétrons/metabolismo , Complexo III da Cadeia de Transporte de Elétrons/genética , Complexo III da Cadeia de Transporte de Elétrons/metabolismo , Complexo IV da Cadeia de Transporte de Elétrons/genética , Complexo IV da Cadeia de Transporte de Elétrons/metabolismo , Regulação da Expressão Gênica , Pós-Condicionamento Isquêmico/métodos , Mitocôndrias Cardíacas/enzimologia , Membranas Mitocondriais/efeitos dos fármacos , Membranas Mitocondriais/enzimologia , Traumatismo por Reperfusão Miocárdica/enzimologia , Traumatismo por Reperfusão Miocárdica/genética , Traumatismo por Reperfusão Miocárdica/patologia , Miocárdio/enzimologia , Miocárdio/patologia , Fosforilação Oxidativa/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Consumo de Oxigênio/efeitos dos fármacos , Ratos , Ratos Wistar
3.
Ageing Res Rev ; 47: 31-40, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29913211

RESUMO

Increase in life-span is commonly related with age-related diseases and with gradual loss of genomic, proteomic and metabolic integrity. Nrf2 (Nuclear factor-erythroid 2-p45 derived factor 2) controls the expression of genes whose products include antioxidant proteins, detoxifying enzymes, drug transporters and numerous cytoprotective proteins. Several experimental approaches have evaluated the potential regulation of the transcription factor Nrf2 to enhance the expression of genes that contend against accumulative oxidative stress and promote healthy aging. Negative regulators of Nrf2 that act preventing it´s binding to DNA-responsive elements, have been identified in young and adult animal models. However, it is not clearly established if Nrf2 decreased activity in several models of aging results from disruption of that regulation. In this review, we present a compilation of evidences showing that changes in the levels or activity of Keap1 (Kelch-like ECH associated protein 1), GSK-3ß (glycogen synthase kinase-3), Bach1, p53, Hrd1 (E3 ubiquitin ligase) and miRNAs might impact on Nrf2 activity during elderly. We conclude that understanding Nrf2 regulatory mechanisms is essential to develop a rational strategy to prevent the loss of cellular protection response during aging.


Assuntos
Envelhecimento/genética , Envelhecimento/metabolismo , Epigênese Genética/fisiologia , Fator 2 Relacionado a NF-E2/genética , Fator 2 Relacionado a NF-E2/metabolismo , Idoso , Animais , Antioxidantes/metabolismo , Regulação da Expressão Gênica , Glicogênio Sintase Quinase 3 beta/genética , Glicogênio Sintase Quinase 3 beta/metabolismo , Humanos , Estresse Oxidativo/fisiologia , Proteômica/tendências
4.
Exp Gerontol ; 96: 89-98, 2017 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-28624355

RESUMO

Cardiovascular diseases (CVDs) are one of the leading causes of death in patients over 60years with Huntington's disease (HD). Here, we investigated if age-related oxidative stress (OS) is a relevant factor to develop cardiac damage in an in vivo model of striatal neurodegeneration induced by 3-nitropropionic acid (3-NP). We also evaluated the potential effect of tert-butylhydroquinone (tBHQ) to increase the Nrf2-regulated antioxidant response in hearts from adult and aged rats intoxicated with 3-NP. Our results showed that 3-NP-treatment did not induce cardiac dysfunction, neither in adult nor in aged rats. However, at the cellular level, adult animals showed higher susceptibility to 3-NP-induced damage than aged rats, which suggest that chronic oxidative stress ongoing during aging might have induced an hormetic response that probably prevented from further 3-NP damage. We also found that the oxidative unbalance concurs with unresponsiveness of the Nrf2-mediated antioxidant response in old animals.


Assuntos
Doença de Huntington/induzido quimicamente , Fator 2 Relacionado a NF-E2/metabolismo , Fármacos Neuroprotetores/farmacologia , Nitrocompostos/toxicidade , Propionatos/toxicidade , Animais , Anti-Hipertensivos , Antioxidantes/farmacologia , Feminino , Cardiopatias/induzido quimicamente , Hidroquinonas/farmacologia , Fator 2 Relacionado a NF-E2/efeitos dos fármacos , Estresse Oxidativo/fisiologia , Ratos Wistar
5.
Int J Oncol ; 50(2): 432-440, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28101578

RESUMO

Breast cancer ranks first in incidence and mortality in working age women. Cancer initiation and progression relies on accumulation of genetic and epigenetic aberrations that alter cellular processes, among them, epithelial to mesenchymal transition (EMT) denotes particularly aggressive neoplasias given its capacity to invade and metastasize. Several microRNAs (miRNA) have been found able to regulate gene expression at the core of EMT. In this study, the Affymetrix CytoScan HD array was used to analyze three different primary tumor cell isolates from Mexican breast cancer patients. We found an amplification in band 22q11.2 shared by the three samples, in the region that encodes miRNA-650. Overexpression of this miRNA has been associated with downregulation of tumor suppressors ING4 and NDRG2, which have been implicated in cancer progression. Using the Pathway Linker platform the ING4 and NDRG2 interaction networks showed a significant association with signaling pathways commonly deregulated in cancer. Also, several studies support their participation in the EMT. Supporting the latter, we found that the three primary isolates were E-cadherin negative, vimentin positive, presented a cancer stem cell-like phenotype CD44+CD24-/low and were invasive in Transwell invasion assays. This evidence suggests that the gain of region 22q11.2 contributes to trigger EMT. This is the first evidence linking miR-650 and breast cancer.


Assuntos
Neoplasias da Mama/patologia , Carcinoma Ductal de Mama/patologia , Transição Epitelial-Mesenquimal/genética , Regulação Neoplásica da Expressão Gênica/genética , MicroRNAs/genética , Adulto , Biomarcadores Tumorais/análise , Neoplasias da Mama/genética , Carcinoma Ductal de Mama/genética , Proteínas de Ciclo Celular/biossíntese , Proteínas de Ciclo Celular/genética , Células Cultivadas , Cromossomos Humanos Par 22 , Feminino , Citometria de Fluxo , Imunofluorescência , Amplificação de Genes , Proteínas de Homeodomínio/biossíntese , Proteínas de Homeodomínio/genética , Humanos , México , Pessoa de Meia-Idade , Análise de Sequência com Séries de Oligonucleotídeos , Proteínas Supressoras de Tumor/biossíntese , Proteínas Supressoras de Tumor/genética
6.
Environ Microbiol Rep ; 7(6): 899-907, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26224366

RESUMO

The nitrogen phosphotransferase system (PTS(Ntr) ) of Pseudomonas putida is a multi-component regulatory device that participates in controlling a variety of physiological processes in a post-translational fashion. A general survey of genes regulated by PtsN exposed transcription of the kdpFABC operon is most conspicuously affected. Measurements of kdpFp promoter activity in different pts mutants showed that PtsN is responsible for repression of kdpFABC transcription. This effect could be assigned mainly to PtsN∼P, depending on the external K(+) concentration. Bacterial two-hybrid assays demonstrated that kdpFp regulation is implemented through direct interaction of the PtsN protein with the sensor kinase KdpD of the KdpD/KdpE two-component system. Interaction between KdpD and PtsN was detectable with a PtsN variant that imitates the non-phosphorylated form as well as with a PtsN type mimicking the phosphorylated form of PtsN. These results raise a regulatory scenario in which the Kdp system is regulated by the action of PtsN through direct interaction with the sensor kinase KdpD, and the outcome of such an interaction depends on the phosphorylation state of PtsN as well as on the external K(+) concentration.


Assuntos
Proteínas de Bactérias/metabolismo , Sistema Fosfotransferase de Açúcar do Fosfoenolpiruvato/metabolismo , Proteínas Quinases/metabolismo , Pseudomonas putida/metabolismo , Regulação Bacteriana da Expressão Gênica , Fosforilação , Potássio/metabolismo , Ligação Proteica , Pseudomonas putida/genética , Transcrição Gênica
7.
Neuroscience ; 265: 1-8, 2014 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-24468104

RESUMO

Adolescence is an important period for brain development. White matter growth is influenced by sex hormones such as testosterone, and the corpus callosum-the largest white matter structure in the human brain-may change structurally during the hormone-laden period of adolescence. Little is known about puberty's relationship to structural brain development, even though pubertal stage may better predict cognitive and behavioral maturity than chronological age. We therefore aimed to establish the presence and direction of pubertal effects on callosal anatomy. For this purpose, we applied advanced surface-based mesh-modeling to map correlations between callosal thickness and pubertal stage in a large and well-matched sample of 124 children and adolescents (62 female and 62 male) aged 5-18years from a normative database. When linking callosal anatomy to pubertal status, only positive correlations reached statistical significance, indicating that callosal growth advances with puberty. In tests of differences in callosal anatomy at different stages of puberty, callosal growth was concentrated in different locations depending on the pubertal stage. Changing levels of circulating sex hormones during different phases of puberty likely contributed to the observed effects, and further research is clearly needed. Direct quantification of sex hormone levels and regional fiber connectivity-ideally using fiber tractography-will reveal whether hormones are the main drivers of callosal change during puberty. These callosal findings may lead to hypotheses regarding cortical changes during puberty, which may promote or result from changes in inter-hemispheric connectivity.


Assuntos
Corpo Caloso/crescimento & desenvolvimento , Puberdade , Adolescente , Criança , Pré-Escolar , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino
8.
Dis Esophagus ; 19(5): 366-72, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16984534

RESUMO

Barrett's esophagus (BE) patients demonstrate a higher distal esophageal acid exposure profile than other gastroesophageal reflux disease patients. Cellular oxidative stress has been proposed to contribute to the development of BE and esophageal adenocarcinoma. However, a relationship between low esophageal pH and oxidative stress has yet to be elucidated. The aim of this study was to determine the duration of low pH exposure in the esophagus of BE patients compared to those with erosive esophagitis (EE) and to test if brief exposure to low pH leads to the induction of reactive oxygen species (ROS). Seventy-three patients with BE or EE were evaluated by 24-hour esophageal pH monitoring and the percentage of time during which there was exposure to pH < or = 4 and pH < or = 2 was recorded. In vitro, Seg-1 and Het-1A cells were evaluated after brief exposure to pH4 or pH2 by flow cytometry and fluorescent microscopy for the production of ROS. BE patients demonstrated a significantly higher exposure to low pH values (pH < or = 2) than EE patients. The mean percent total time, duration and mean number of reflux episodes at pH < or = 2 were 2.8 +/- 0.53%, 28.8 +/- 3.6 seconds and 79 +/- 11.4 episodes in BE patients, whereas in EE patients they were significantly less, 1.16 +/- 0.3%, 15.6 +/- 1.2 seconds and 48.3 +/- 8.8 episodes, respectively (P < 0.05). In vitro experiments indicate that esophageal cells, when exposed to pH 2, produce ROS. In vitro studies using brief pH 2 exposure are biologically relevant to the clinical situation. Our studies indicate that such exposure induces oxidative stress. This stress may cause DNA damage, mutations and progression to cancer.


Assuntos
Esôfago de Barrett/fisiopatologia , Monitoramento do pH Esofágico , Estresse Oxidativo/fisiologia , Adenocarcinoma/metabolismo , Linhagem Celular , Células Epiteliais/metabolismo , Neoplasias Esofágicas/metabolismo , Esofagite/fisiopatologia , Esofagoscopia , Feminino , Citometria de Fluxo , Humanos , Masculino , Microscopia de Fluorescência , Pessoa de Meia-Idade , Espécies Reativas de Oxigênio/metabolismo
9.
Andrologia ; 33(2): 113-21, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11350375

RESUMO

Mammalian spermatozoa maintain precisely regulated ionic gradients that must be modified during capacitation and the acrosome reaction. In other cell types, ionic gradients are mainly regulated by the presence in plasma membranes of three metabolically different types of ATPases. The modifications induced during in vitro capacitation of rabbit spermatozoa by the specific inhibition of V-type H+-ATPases with bafilomycin A were studied. We used chlortetracycline binding to rabbit spermatozoa to monitor capacitation, and the coomassie brilliant blue method to identify acrosome-reacted sperm cells. There was a significant difference between the percentage of epididymal (66 +/- 7%) and ejaculated (43 +/- 11%) spermatozoa capacitated in vitro, after a 6-h incubation period in the presence of Ca2+ without ATPase inhibitor. The presence of bafilomycin significantly reduced these numbers (25 +/- 11 and 16+/- 8%, epididymal and ejaculated spermatozoa, respectively) and eliminated the difference. Ejaculated spermatozoa capacitated in the absence of bafilomycin showed a linear increase in the percentage of acrosome reactions induced by the addition of A23187 (12 +/- 5, 23+/- 6 and 31 +/- 5 after 15, 30 and 45 min). The presence of 0.2 micromol l-1 bafilomycin during the capacitation incubation induced a significant decrease in the acrosome reaction percentages (4 +/- 2, 8 +/- 3 and 14 +/- 4 after 15, 30 and 45 min). The addition of bafilomycin after the capacitating period had no effect upon the induction of the acrosome reaction by A23187. These results indicate that vacuolar ATPases play an important role during rabbit sperm capacitation. However, once the spermatozoa have been capacitated, V-type ATPases do not have a significant participation during the acrosome reaction.


Assuntos
Antibacterianos/farmacologia , Inibidores Enzimáticos/farmacologia , Macrolídeos , Lectinas de Plantas , ATPases Translocadoras de Prótons/antagonistas & inibidores , Capacitação Espermática/efeitos dos fármacos , ATPases Vacuolares Próton-Translocadoras , Reação Acrossômica , Animais , Calcimicina/farmacologia , Clortetraciclina , Ejaculação , Epididimo/citologia , Fertilização in vitro , Fluoresceína-5-Isotiocianato , Corantes Fluorescentes , Ionóforos/farmacologia , Lectinas , Masculino , Coelhos , Motilidade dos Espermatozoides
11.
Pharmacol Biochem Behav ; 61(4): 445-50, 1998 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9802840

RESUMO

Calmodulin (CaM) presence and concentration was determined (RIA) in the rat hypothalamus (2, 6, 12, 24 h and 90 days after birth) in vehicle-treated animal (controls), in testosterone propionate (TP)-treated females (30 microg/rat subcutaneously 1 h after birth) and in tamoxifen-treated males (200 microg/rat subcutaneously 1 h after birth). CaM concentration, either as total content/hypothalamus or as concentration per mg ww, was significantly higher in both male and female adult rats than in newborn subjects. CaM concentration/mg protein increased with age, being two times higher in adult males and greater than three times higher in adult females than in their respective newborns. Two, 12, and 24 h after birth CaM concentration was significantly lower in control females than in control males. This relation was reversed in adults in which CaM concentration was higher in females. The application of TP to the females and tamoxifen to the males, induced a significant decrease in CaM/mg protein, both in the newborn (2 and 6 h) and in the adult animals. In adults, treated females had CaM concentrations similar to those found in control males. Our data suggest: first, a lasting effect of newborn hormonal treatment upon the CaM concentration in rat hypothalamus; second, that CaM is preferentially synthesized in the adult female hypothalamus, indicating an important role of this protein in female reproductive function.


Assuntos
Calmodulina/metabolismo , Hipotálamo/metabolismo , Diferenciação Sexual , Animais , Animais Recém-Nascidos , Feminino , Hipotálamo/crescimento & desenvolvimento , Masculino , Radioimunoensaio , Ratos , Ratos Sprague-Dawley , Tamoxifeno/farmacologia , Testosterona/farmacologia
12.
Int J Androl ; 20(2): 118-25, 1997 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9292323

RESUMO

To further investigate the nature of neuroendocrine disturbances of the hypothalamopituitary-gonadal axis in idiopathic male infertility, we studied 12 infertile men with oligoasthenozoospermia and 13 euspermic controls, matched for age and body mass index, by blood withdrawal at 10-min intervals for 8 h to analyse pulsatile release of bioactive LH (b-LH). The rat interstitial cell testosterone (RICT) bioassay was used in conjunction with a recently validated multiparameter deconvolution algorithm, to estimate the endogenous half-life of b-LH, its secretory burst frequency, amplitude, duration and mass. Oligoasthenospermic men exhibited significant (p < 0.05) alterations within the LH axis; namely: (1) a prolonged half-life of b-LH (92 min in euspermic men, 127 min in oligoasthenospermic men); (2) a reduced b-LH secretory burst amplitude (2.2 +/- 1.2 IU/l/min in euspermic men, 1.7 +/- 0.8 IU/l/min in oligoasthenospermic men); (3) a lower bioactive/immunoactive (b/i) ratio for LH secretory burst amplitude (14 in euspermic men, 4 in oligoasthenospermic men); (4) a reduced b/i ratio in the mass of LH secreted per burst (5.4 in euspermic men, 4.1 in oligoasthenospermic men) and (5) decreased coordinate release of b-LH and testosterone in infertile men, as assessed by cross-correlation analysis. These disturbances differ from the neuroendocrine dysregulation described in other states of male hypogonadotrophism.


Assuntos
Hormônio Luteinizante/metabolismo , Oligospermia/fisiopatologia , Ciclos de Atividade , Adulto , Algoritmos , Animais , Bioensaio/métodos , Humanos , Hormônio Luteinizante/sangue , Hormônio Luteinizante/deficiência , Masculino , Menotropinas/farmacologia , Oligospermia/sangue , Radioimunoensaio , Ratos , Valores de Referência , Reprodutibilidade dos Testes , Testosterona/metabolismo
13.
Ginecol Obstet Mex ; 65: 413-21, 1997 Oct.
Artigo em Espanhol | MEDLINE | ID: mdl-9432472

RESUMO

In the "male factor" entity, the structural and functional correlation determining the sperm fertilizing capacity is constituted by a group of cellular factors that must be evaluated in the semen of the infertile men. Structurally the spermatozoa of the head, the middle piece and the flagellum. The head has a highly condensed haploid nucleus, surrounded by a thin layer of cytoplasmic material, which is covered in a cap-like fashion by the membrane limiting the acrosome. This last organelle, which has characteristics similar to those of a secretory granule, secretes in a programmed way the hydrolytic enzymes that facilitate the fertilization process. The middle piece contains the mitocondrail sheet, responsible for the energy metabolism of the sperm cell. The flagellum has the same basic structure of other cilia or flagella, but also has particular characteristics due to the presence of the outer dense fibers and the fibrous sheath. In the semen analysis from infertile men the abnormalities most frequently observed belong to the number, morphology, variability, motility of capacitation-acrosome reaction of the sperm cells. However, due to the apparent multifactorial etiology of the male factor, now a days we only have few options for medical or pharmacological treatment. In this paper we review the morphology and ultrastructure considered as "normal" in the human spermatozoa, as well as we describe the most frequent alterations in these parameters. At the same time, we discuss the impact of sperm motility and of the capacitation-acrosome reaction process in male fertility.


Assuntos
Fertilização/fisiologia , Motilidade dos Espermatozoides , Espermatozoides/fisiologia , Acrossomo/fisiologia , Haploidia , Humanos , Infertilidade Masculina , Masculino , Capacitação Espermática , Contagem de Espermatozoides , Espermatozoides/ultraestrutura
14.
Int J Lepr Other Mycobact Dis ; 64(4): 417-27, 1996 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9030108

RESUMO

In search for reliable, nonexpensive procedures for tuberculosis diagnosis suitable for seroepidemiological studies in leprosy-endemic areas, enzyme-linked immunosorbent assays (ELISAs) with whole intact bacilli, whole lipid-free bacilli and protein-enriched soluble extracts from the H37Rv Mycobacterium tuberculosis strain were evaluated. Sera tested came from 47 active, pulmonary tuberculosis adult cases, 60 household contacts of active tuberculosis cases, 20 lepromatous leprosy adult patients, and 67 healthy adult controls obtained from low and high leprosy and tuberculosis endemicity areas. There was no influence of such endemicity levels in the number of positive results in control sera. Antibody levels obtained with each of the antigens in ELISAs were significantly different in tuberculosis patients and the control groups. Ten percent of tuberculosis contacts were positive with some of the antigens and three of them showed suggestive chest radiographs. The best combination for a high number of positive results with tuberculosis sera and low positive results with leprosy sera was the BCG soluble extract (91% and 15%, respectively). This preparation also yielded excellent sensitivity and specificity values for tuberculosis (91.5% and 92.5%, respectively). These data suggest that BCG soluble extract ELISAs could provide helpful information to estimate tuberculosis prevalence only in leprosy-free areas, under a situation of unavailability of purified antigens. In pulmonary cases, sputum microscopic examination and culture have higher sensibility than serodiagnosis; therefore, the utilization of BCG soluble extract ELISAs as a diagnostic aid in individual patients with suspected active tuberculosis only can be useful in extrapulmonary cases.


Assuntos
Anticorpos Antibacterianos/sangue , Antígenos de Bactérias/imunologia , Ensaio de Imunoadsorção Enzimática , Hanseníase Virchowiana/diagnóstico , Mycobacterium/imunologia , Tuberculose Pulmonar/diagnóstico , Estudos de Casos e Controles , Família , Humanos , Hanseníase Virchowiana/imunologia , Mycobacterium bovis/imunologia , Mycobacterium leprae/imunologia , Mycobacterium tuberculosis/imunologia , Sensibilidade e Especificidade , Tuberculose Pulmonar/imunologia
15.
J Clin Endocrinol Metab ; 81(2): 524-9, 1996 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-8636262

RESUMO

To investigate the nature of neuroendocrine disturbances of the hypothalamo-pituitary-gonadal axis in idiopathic male infertility, we studied 14 infertile men with oligoasthenozoospermia (OLIGO) and 15 age-, body mass index-, and community-matched euspermic controls by blood withdrawal at 10-min intervals for 12 h to encompass basal (8-h) and exogenous GnRH-stimulated (4-h) pulsatile release of LH and FSH (by immunoradiometric assay) as well as testosterone (by RIA). Deconvolution analysis was used to estimate endogenous LH and FSH half-lives, secretory burst frequency, amplitude, duration, and mass. OLIGO men exhibited normal serum concentrations of total, free, and percent dialyzable testosterone and estradiol, but distinct dynamic alterations within the LH and FSH axes; namely (P < 0.05), 1) a prolonged half-life of LH (OLIGO, 95 +/- 19 min; control, 80 +/- 9.3 min) and a reduced half-life of FSH (OLIGO, 260 +/- 79 min; control, 320 +/- 93 min); 2) a low LH, but normal FSH, secretory burst frequency (OLIGO, 12 +/- 3.4; control, 15 +/- 3.0 LH pulses/day); 3) a decreased serum testosterone peak frequency (OLIGO, 16 +/- 4.3; control, 21 +/- 3.2 peaks/day); and 4) an amplified mass of LH (1.1- to 1.3-fold higher in OLIGO) and FSH (2.4- to 2.7-fold higher in OLIGO) secreted per burst basally as well as after GnRH injection. These disturbances were readily distinguishable from the neuroendocrine dysregulation described in other states of male hypogonadotropism (e.g. uremia, fasting, and aging).


Assuntos
Hormônio Foliculoestimulante/metabolismo , Infertilidade Masculina/fisiopatologia , Hormônio Luteinizante/metabolismo , Oligospermia/fisiopatologia , Periodicidade , Adulto , Hormônio Liberador de Gonadotropina , Humanos , Masculino , Testosterona/metabolismo
16.
Arch Androl ; 36(1): 17-23, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-8824664

RESUMO

Interaction between spermatozoa and female reproductive tract fluids involves both losses of surface proteins and adsorption of exogenous fluids' components. To study the functional consequences of this interaction, sperm acrosome reaction was evaluated after incubation at 37 degrees C in uterine (UF) and/or oviductal (OF) fluid collected at estrus from conscious ewes. Ram spermatozoa were collected through the catheterized vas deferens. The fluids had previously been diluted with equal volumes of BWW medium or dialyzed against BWW. Control incubations were in BWW. Twenty minutes before the end of incubation, Ca2+ (2.5 mM) was added to induce the acrosome reaction, which was assessed using a triple stain technique. Results showed that 22-24% of the sperm experienced acrosome reaction after sequential incubation in UF (1 h) and OF (4 h), or in UF alone (5 h). Exposure to OF alone induced 13% of acrosome reaction. When the spermatozoa were preincubated in UF followed by OF, the acrosome reaction percentage increased almost linearly with time. When incubated in UF alone, this percentage increased steadily with time, whereas a plateau was reached after 1 h of incubation in OF alone. Dialysis of the fluids did not modify the results. These results show that ewe reproductive tract secretions may capacitate ram spermatozoa in vitro, evaluated by their efficacy to induce acrosome reaction.


Assuntos
Acrossomo/metabolismo , Tubas Uterinas/metabolismo , Capacitação Espermática/fisiologia , Espermatozoides/metabolismo , Útero/metabolismo , Animais , Sobrevivência Celular , Feminino , Masculino , Ovinos
18.
Arch Med Res ; 23(3): 83-92, 1992.
Artigo em Inglês | MEDLINE | ID: mdl-1308807

RESUMO

In this paper we briefly review the recent advances in the understanding of human sperm capacitation, fundamentally focused to give help to the practitioners involved in assisted reproduction. Sperm capacitation has been the subject of study for many years in several animal species, but during the past ten years the advances in assisted reproduction procedures have made important contributions in the progress of this topic in relation to human spermatozoa. In this manuscript we analyze the metabolic, membranal and physiological changes observed in these cells during in vitro capacitation and their relationships with the female genital tract secretions, as well as with the homologous oocytes.


Assuntos
Acrossomo/fisiologia , Técnicas Reprodutivas , Capacitação Espermática , Membrana Celular/fisiologia , Metabolismo Energético , Matriz Extracelular/fisiologia , Feminino , Humanos , Masculino , Modelos Biológicos , Motilidade dos Espermatozoides , Espermatozoides/metabolismo
19.
Ginecol Obstet Mex ; 59: 229-37, 1991 Jul.
Artigo em Espanhol | MEDLINE | ID: mdl-1769606

RESUMO

The recent advances in assisted reproduction procedures have helped to the better understanding of the female reproductive physiology and pathology, however, male infertility remains as a poor explained medical problem, nevertheless it occurs in almost 50% of infertile couples. Oligoasthenozoospermia is one of the more common causes of male infertility, therefore we measured in 10 patients with this diagnosis and in 10 fertile euspermic men, besides the parameters included in the standard semen analysis, the quantitative motility (photography method), capacitation-acrosome reaction and the sperm ability to fertilize zona-free hamster oocytes, with the aim to correlate the morphofunctional characteristics of the male gametes with their fertilizing capacity. The results showed significant differences in every parameter studied, including the correlation analysis. In relation with the in vitro induction of the acrosome reaction in both groups, we found significant correlations of the sperm fertilizing ability and the progressive sperm motility with this parameter (fertile group: RS = 0.834, P less than 0.005 & RS = 0.612, P less than 0.05; infertile group: RS = 0.986, P less than 0.001 & RS = 0.536, P less than 0.05 respectively), nevertheless the sperm rate which completed this process was low in relation to the total sperm population even in the fertile men (9.4 +/- 2.0% & 4.4 +/- 2.5% acrosome reacted cells after 18 h of incubation, in the fertile and infertile males respectively). The results also showed the presence of fully capacitated spermatozoa in both groups, since they penetrated the zona-free hamster eggs and decondensed their chromatin (73.9 +/- 13.4% & 10.4 +/- 7.7% penetrated eggs in the euspermic and oligoasthenozoospermic individuals respectively), however, the spermatozoa from the oligoasthenozoospermic men showed low polyspermy indexes too (0.1 penetrated spermatozoa/inseminated oocyte). In this last group we found, in addition, that the mean sperm velocity and the abnormal sperm morphology rate showed significant correlations with the fertilizing ability of the male gametes too (RS = 0.986, P less than 0.005 & RS = -0.942, P less than 0.005. respectively). These data allow us to suggest that before an infertile man is involved in any assisted reproduction program, the presence of possible morphofunctional alterations in the spermatozoa be analyzed, with the aim to be able to make a better prognosis about the success with these patients.


Assuntos
Fertilização , Oligospermia/fisiopatologia , Espermatozoides/patologia , Acrossomo/fisiologia , Animais , Cricetinae , Feminino , Humanos , Masculino , Oligospermia/etiologia , Oligospermia/patologia , Capacitação Espermática , Contagem de Espermatozoides , Motilidade dos Espermatozoides , Interações Espermatozoide-Óvulo , Espermatozoides/anormalidades
20.
Ginecol Obstet Mex ; 59: 85-92, 1991 Mar.
Artigo em Espanhol | MEDLINE | ID: mdl-1860676

RESUMO

The role of inhibin in the testicular function and its relation with other hormone regulation spermatogenesis have not been elucidated in the human, therefore we studied by RIA the serum concentrations of this testicular secretion product, as well as those of LH, FSH, T and E2 and their possible correlation with some parameters evaluated by spermatobioscopy (cell number, motility, morphology and immature germinal cells) in fertile, oligozoospermic and azoospermic men. We did not find significant differences in inhibin concentration between fertile and oligozoospermic males; however in the azoospermic group the mean inhibin concentration was significantly higher (722.9 +/- 137.9 U/l in the fertile men; 658.5 +/- 147.1 and 963.1 +/- 300.9 U/l in the oligozoospermic and azoospermic groups respectively), in spite of data dispersion in the 3 study groups. Among the fertile males we found a negative significant correlation between the inhibin and the LH and FSH concentrations (p less than 0.05), while in the oligozoospermic patients this negative correlation was observed with T concentration. In the fertile males inhibin also showed correlation with the sperm percentage with normal morphology and with the immature germinal cells in semen; in the oligozoospermic group this glycoprotein showed correlation with the sperm count and the germinal cells concentration. We also found correlation between testosterone and/or LH concentrations and sperm count in both groups. These results indicate modifications in the hormonal concentrations regulating the testicular function and in their relationship, in men with testicular damage, which can render a change in the mechanisms controlling this function.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Estradiol/sangue , Gonadotropinas Hipofisárias/sangue , Inibinas/sangue , Oligospermia/sangue , Testosterona/sangue , Humanos , Masculino , Oligospermia/fisiopatologia , Motilidade dos Espermatozoides , Espermatozoides
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