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1.
Int J Mol Sci ; 22(4)2021 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-33562271

RESUMO

The pathophysiology of Polycystic Ovary Syndrome (PCOS) is quite complex and different mechanisms could contribute to hyperandrogenism and anovulation, which are the main features of the syndrome. Obesity and insulin-resistance are claimed as the principal factors contributing to the clinical presentation; in normal weight PCOS either, increased visceral adipose tissue has been described. However, their role is still debated, as debated are the biochemical markers linked to obesity per se. Oxidative stress (OS) and low-grade inflammation (LGI) have recently been a matter of researcher attention; they can influence each other in a reciprocal vicious cycle. In this review, we summarize the main mechanism of radical generation and the link with LGI. Furthermore, we discuss papers in favor or against the role of obesity as the first pathogenetic factor, and show how OS itself, on the contrary, can induce obesity and insulin resistance; in particular, the role of GH-IGF-1 axis is highlighted. Finally, the possible consequences on vitamin D synthesis and activation on the immune system are briefly discussed. This review intends to underline the key role of oxidative stress and low-grade inflammation in the physiopathology of PCOS, they can cause or worsen obesity, insulin-resistance, vitamin D deficiency, and immune dyscrasia, suggesting an inverse interaction to what is usually considered.


Assuntos
Inflamação/complicações , Estresse Oxidativo , Síndrome do Ovário Policístico/patologia , Animais , Feminino , Humanos , Síndrome do Ovário Policístico/etiologia
2.
Adv Urol ; 2012: 903931, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-21915179

RESUMO

Oxidative stress is a mechanism underlying different kinds of infertility in human males. However, different results can be observed in relation to the method used for its evaluation. Varicocele patients show a number of biochemical abnormalities, including an altered distribution of coenzyme Q between seminal plasma and sperm cells and also an apparent defect in the utilization of antioxidants. Moreover, an influence of systemic hormones on seminal antioxidant system was observed too. Finally, the effects of surgical treatment on oxidativestress indexes and the possible usefulness of some medical therapies, like coenzyme Q supplementation, are discussed. In conclusion, published data show a role of oxidative stress in varicocele-related male infertility, but at present we do not know the precise molecular mechanisms underlying these phenomena.

3.
Fertil Steril ; 88(4): 915-24, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17601602

RESUMO

OBJECTIVE: To find optimal clinical rules that maximize the probability of conception while limiting the number of intercourse days required. DESIGN: Multicenter prospective study. Women were followed prospectively while they kept daily records of menstrual bleeding, intercourse, and mucus symptom characteristics. In some cycles, women sought to conceive, whereas in other cycles, they sought to avoid pregnancy. SETTING: Four centers providing services on fertility awareness. PATIENT(S): One hundred ninety-one healthy women using the Billings Ovulation Method. Women were invited to enroll by their instructors if they satisfied the entry criteria. We excluded cycles in which mucus was not recorded on a day with intercourse. INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): Clinically identified pregnancies. There were 161 clinically identified pregnancies in 2,536 menstrual cycles from 191 women. RESULT(S): Our approach relies on a statistical model that relates daily predictors, such as type of mucus symptom, to the day-specific probabilities of conception. By using Bayesian methods to search over a large set of possible clinical rules, focusing on rules based on calendar and mucus, we found that simple rules that are based on days within the midcycle calendar interval that also have the most fertile-type mucus symptom present have high utility. CONCLUSION(S): Couples can shorten their time to pregnancy efficiently by timing intercourse on days that the most fertile-type mucus symptom is observed at the vulva.


Assuntos
Muco do Colo Uterino/metabolismo , Coito , Fertilização , Métodos Naturais de Planejamento Familiar , Adolescente , Adulto , Teorema de Bayes , Feminino , Humanos , Masculino , Menstruação , Gravidez , Taxa de Gravidez , Estudos Prospectivos , Fatores de Tempo
4.
J Androl ; 25(1): 44-9, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-14662785

RESUMO

In order to explore the impact of surgical treatment on antioxidant defense system in varicocele (VAR), we evaluated seminal total antioxidant capacity (TAC) in 25 patients affected by VAR, in 14 patients studied 10-24 months after varicocelectomy (post-VAR) and separated into normo- and oligospermic groups, and in 24 non-VAR control patients with seminal parameters matched to patients with VAR in the oligo- and normospermic groups (7 subjects with idiopathic oligospermia and 17 normal fertile subjects). TAC was measured in seminal plasma with the system H(2)O(2)-metamyoglobin as a source of radicals, which interact with a chromogen 2,2',-azinobis (3-ethylbenzothiazoline-6-sulphonate) (ABTS), generating a radical cation spectroscopically detectable. The presence of antioxidants induces a lag time in the production of ABTS cation proportional to the concentration of antioxidant compounds. When whole groups of patients were analyzed, lag values were significantly higher in VAR vs non-VAR controls (mean +/- SEM, 106.6 +/- 8.8 seconds vs 78.7 +/- 8.8 seconds) but were not modified by surgery (mean +/- SEM, 105.8 +/- 8.6 seconds). In groups separated according to seminal parameters, oligospermic VAR presented significantly higher lag values than oligospermic controls. Finally, when exploring a possible association of TAC with seminal parameters, we found a significant correlation between lag and sperm motility only in patients with VAR who were in the normospermic group (r = 0.65, P <.01). This correlation was not yet manifest post-VAR. In conclusion, surgical treatment does not seem to modify absolute values of TAC but influences its fine regulation and relationships with sperm motility.


Assuntos
Antioxidantes/metabolismo , Sêmen/metabolismo , Varicocele/metabolismo , Varicocele/cirurgia , Adulto , Humanos , Infertilidade Masculina/metabolismo , Infertilidade Masculina/cirurgia , Masculino , Pessoa de Meia-Idade , Espécies Reativas de Oxigênio/metabolismo , Sêmen/citologia , Motilidade dos Espermatozoides , Espermatozoides/metabolismo
5.
Fertil Steril ; 79 Suppl 3: 1577-83, 2003 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12801563

RESUMO

OBJECTIVE: To explore a possible molecular defect linked to infertility, studying total antioxidant capacity (TAC) of seminal plasma in varicocele (VAR). DESIGN: Case-series study. SETTINGS: Volunteers in an academic research environment and out-patients in clinical service. PATIENT(S): Twenty-five VAR patients (9 oligospermic and 16 normospermic) vs 24 non-VAR controls (7 subjects with idiopathic oligospermia and 17 normospermic subjects). INTERVENTION(S): Evaluation of seminal plasma TAC. MAIN OUTCOME MEASURE(S): TAC was measured using myoglobin, as a source of radicals, which interact with a chromogen 2,2'-azinobis(3-ethylbenzothiazoline-6-sulphonate) (ABTS), whose radical cation is spectroscopically detectable. The latency phase (Lag) in the accumulation of ABTS cation is proportional to antioxidant concentration. RESULT(S): Lag showed significantly greater values in the all VAR patients vs non-VAR subjects. Oligospermic-VAR patients showed the greatest values. Lag and sperm motility significantly correlated in VAR normospermic patients. Follicle-stimulating hormone (FSH) showed significant inverse association with Lag in same group. CONCLUSION(S): The augmented Lag values could indicate an ineffective utilization of antioxidants in oligospermic-VAR, while in normo-VAR the direct correlation between TAC and motility suggest a potential protective role toward sperm motility. In the same group, the inverse correlation with FSH suggests that greater FSH levels induce a better utilization of antioxidants by spermatozoa.


Assuntos
Antioxidantes/metabolismo , Varicocele/metabolismo , Adulto , Hormônio Foliculoestimulante/sangue , Humanos , Masculino , Pessoa de Meia-Idade , Motilidade dos Espermatozoides , Testosterona/sangue
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