Antioxidant Actions of Melatonin: A Systematic Review of Animal Studies.

Melatonin is an indoleamine with crucial antioxidant properties that are used to combat inflammatory and neoplastic processes, as well as control transplants. However, the clinical applications of melatonin have not yet been fully consolidated in the literature and require in-depth analysis. OBJECTIVES: This study reviewed the literature on the antioxidant properties of melatonin in rat models. METHODS: We followed the guidelines of the Preferred Reporting Items for Systematic Reviews and Meta-analyses and used the PubMed, LILACS, and Cochrane databases, Google Scholar, and article references, irrespective of publication time. RESULTS: Ten articles involving 485 rats were selected, and the effects of melatonin on antioxidant markers were investigated. Melatonin increased superoxide dismutase in nine studies, glutathione peroxidase in seven studies, and catalase in five studies. In contrast, melatonin reduced glutathione in three studies and malonaldehyde in seven of eight studies. CONCLUSION: Our findings suggest that melatonin effectively reduces oxidative stress.

Impact of hormone therapy on the bone density of women with premature ovarian insufficiency: A systematic review.

INTRODUCTION: Women with premature ovarian insufficiency (POI) are exposed to a long period of estrogenic deficiency, which potentially brings higher health risks, especially regarding bone health. We performed a systematic review of the literature to evaluate the effect of hormone therapy (HT) on bone mineral density (BMD) in women with POI. MATERIALS AND METHODS: A systematic search was performed of the MEDLINE and EMBASE databases up to September 2021. We included studies that analyzed women with idiopathic (spontaneous) POI treated with HT, and those who had BMD evaluated. Analysis of risk of bias of studies selected was performed. RESULTS: We found 335 articles and selected 16 studies according to the inclusion criteria. Most of the studies revealed lower bone density in both the femoral neck and lumbar spine of women with POI compared with healthy women. Bone mass had the tendency to remain stable in women treated with estrogen + progestin therapy. However, in women already with bone mass loss, the therapy - in the doses most frequently used - was not able to revert the loss. Higher doses of estrogen seem to have a positive impact on BMD, as did combined oral contraceptives used continuously. Also, the interruption of HT for longer than one year was linked to significant bone loss. CONCLUSION: Although HT brings clear benefits, further studies are needed to establish its long-term effects, as well as doses and formulations with better protective effects on the bone mass of these women.

Does bisphenol A (BPA) participates in the pathogenesis of Polycystic Ovary Syndrome (PCOS)?

PCOS is an endocrine disorder characterized by chronic anovulation, hyperandrogenism, and polycystic ovaries. Its etiology is uncertain. It is debated whether BPA would be a component of the environmental factor in the etiology of PCOS. Contamination by BPA can occur from food packaging (exposure during the diet) and through skin absorption and/or inhalation. It can be transferred to the fetus via the placenta or to the infant via breast milk, and it can be found in follicular fluid, fetal serum, and amniotic fluid. The phenolic structure of BPA allows it to interact with Estrogen Receptors (ERs) through genomic signaling, in which BPA binds to nuclear ERα or Erß, or through nongenomic signaling by binding to membrane ERs, prompting a rapid and intense response. With daily and constant exposure, BPA's tendency to bioaccumulate and its ability to activate nongenomic signaling pathways can alter women's metabolic and reproductive function, leading to hyperandrogenism, insulin resistance, obesity, atherogenic dyslipidemia, chronic inflammatory state, and anovulation and favoring PCOS. The harmful changes caused by BPA can be passed on to future generations without the need for additional exposure because of epigenetic modifications. Not only high BPA levels can produce harmful effects, but at low levels, BPA may be harmful when exposure occurs during the most vulnerable periods, such as the fetal and neonatal periods, as well as during the prepubertal age causing an early accumulation of BPA in the body. Learning how BPA participates in the pathogenesis of PCOS poses a challenge and further studies should be conducted.

Melatonin and the cardiovascular system in animals: systematic review and meta-analysis.

Melatonin, a hormone released by the pineal gland, demonstrates several effects on the cardiovascular system. Herein, we performed a systematic review and meta-analysis to verify the effects of melatonin in an experimental model of myocardial infarction. We performed a systematic review according to PRISMA recommendations and reviewed MEDLINE, Embase, and Cochrane databases. Only articles in English were considered. A systematic review of the literature published between November 2008 and June 2019 was performed. The meta-analysis was conducted using the RevMan 5.3 program provided by the Cochrane Collaboration. In total, 858 articles were identified, of which 13 were included in this review. The main results of this study revealed that melatonin benefits the cardiovascular system by reducing infarct size, improving cardiac function according to echocardiographic and hemodynamic analyses, affords antioxidant effects, improves the rate of apoptosis, decreases lactate dehydrogenase activity, enhances biometric analyses, and improves protein levels, as analyzed by western blotting and quantitative PCR. In the meta-analysis, we observed a statistically significant decrease in infarct size (mean difference [MD], -20.37 [-23.56, -17.18]), no statistical difference in systolic pressure (MD, -1.75 [-5.47, 1.97]), a statistically significant decrease in lactate dehydrogenase in animals in the melatonin group (MD, -4.61 [-6.83, -2.40]), and a statistically significant improvement in the cardiac ejection fraction (MD, -8.12 [-9.56, -6.69]). On analyzing potential bias, we observed that most studies presented a low risk of bias; two parameters were not included in the analysis, and one parameter had a high risk of bias. Melatonin exerts several effects on the cardiovascular system and could be a useful therapeutic target to combat various cardiovascular diseases.

Ultrasound in the first trimester of pregnancy.

The Guidelines Project, an initiative of the Brazilian Medical Association, aims to combine information from the medical field in order to standardize producers to assist the reasoning and decision-making of doctors. The information provided through this project must be assessed and criticized by the physician responsible for the conduct that will be adopted, depending on the conditions and the clinical status of each patient.

Contraception and reproductive planning during the COVID-19 pandemic.

INTRODUCTION: The coronavirus disease (COVID-19) is a global health emergency. Major disruption to healthcare services during the current COVID-19 pandemic will last even after its peak. Sexual and reproductive health (SRH), specially contraception, needs to be understood as an essential service. AREAS COVERED: This paper is a narrative review. Data from PubMed/MEDLINE, Scopus, and websites of scientific societies were screened during the months of April and May 2020. It addresses the main aspects related to contraception during the COVID-19 pandemic, with special emphasis on family planning services, extended use of long-acting reversible contraceptive (LARC) methods, drug interactions, and thromboembolism risk. We also specified some issues focused on the Brazilian reality. EXPERT OPINION: Ensuring proper contraception use in the COVID-19 time is very important. We encourage women, healthcare providers, policymakers, and the society to consider SRH services as priority.

Does gestrinone antagonize the effects of estrogen on endometrial implants upon the peritoneum of rats?

OBJECTIVE: To evaluate the effects of estrogen treatment in combination with gestrinone on an experimental rat model of endometriosis. METHODS: Uterine transplants were attached to the peritoneum of female Wistar rats via a surgical autotransplantation technique. The implanted area was measured during the proestrus phase and after hormonal treatment. We performed morphometric analysis and examined the macroscopic and morphometric alterations of endometrial implants after hormonal treatment in ovariectomized rats. RESULTS: The high dose of estrogen caused macroscopic increases in the endometrial implant group compared with other groups, which were similar to increases in the proestrus phase. The low dose showed morphometric development of implants, such as an increase in number of endometrial glands, leukocyte infiltration and mitosis. Gestrinone antagonized both doses of estrogen. CONCLUSION: Our findings suggest that gestrinone antagonizes estrogen's effects on rat peritoneal endometrial implants.

Proliferation of the superficial epithelium of ovaries in senile female rats following oral administration of conjugated equine estrogens.

OBJECTIVE: To evaluate the effect of different concentrations of estrogen on the ovarian superficial epithelium in senile female rats. DESIGN: Fifty female rats at 15 months of age and with irregular estrous cycles were selected and randomly divided into five experimental groups containing equal numbers of animals in each: GPROP, control group receiving vehicle only; GE0.05mg, group receiving conjugated equine estrogens (CEE) at a dose of 50 microg/kg; GE0.5mg, group receiving CEE at 500 microg/kg; GE1mg, group receiving CEE at 1 mg/kg; and GE2mg, receiving CEE at 2 mg/kg. The length of treatment was 21 days. After this period, the animals were anesthetized and the ovaries were fixed in 10% formaldehyde and processed for routine histology. Histomorphology was analyzed by light microscopy, and histomorphometrics were evaluated using the Imagelab program. RESULTS: In the GPROP and GE0.05mg groups, the superficial epithelium of the ovary had a simple cuboidal shape, and as the estrogen dose increased, the epithelium thickened, with pseudo-stratified or stratified epithelium appearing in the GE2mg group. The animals in the group given the highest estrogen dose (GE2mg) showed the thickest ovarian epithelium and the largest perimeter and surface area of the surface ovarian epithelium (P < 0.01). However, the difference in epithelium thickness between the GE0.5mg and GE1mg groups was only slight. CONCLUSION: Our data suggest that CEE at a dose of 2 mg/kg may induce marked proliferation of rat ovarian epithelium.

Are women living with HIV prone to osteoporosis in postmenopause? A systematic review.

BACKGROUND: Some researchers have suggested that HIV infections can increase the cytokines, which might interfere with the bone metabolism and increase the risk of bone mass loss. However, this issue has yet to be consolidated in postmenopausal women. OBJECTIVE: To analyze studies that evaluated the loss of bone mass through DEXA in women living with HIV. MATERIALS AND METHODS: A systematic review was conducted following the PRISMA guideline. The MEDLINE, EMBASE and Cochrane databases were consulted from January 1987 to March 2017. Studies assessing bone mineral density (BMD) in postmenopausal women living with HIV were included. The secondary outcome was to evaluate the impact of antiretroviral on BMD. RESULTS: Sixty percent of the manuscripts suggested that women living with HIV had more bone loss than women in the control group, mainly in the lumbar spine. Forty percent did not observe any difference between groups. One study reported the influence of antiretroviral drugs on bone mass but did not find any difference between groups. CONCLUSION: Our data suggest that HIV infections may have a negative influence on bone mass loss in women. Further studies on the mechanism of this HIV consequence are necessary to clarify the connection as well as the impact of the antiretroviral action on BMD in postmenopausal women.

Systematic review and meta-analysis of the effect of bipolar electrocoagulation during laparoscopic ovarian endometrioma stripping on ovarian reserve.

BACKGROUND: Laparoscopic stripping is the gold-standard treatment for ovarian endometriosis. The choice of hemostasis method might affect ovarian reserve. OBJECTIVES: To determine whether bipolar electrocoagulation is more detrimental to ovarian reserve than non-thermal hemostasis methods. SEARCH STRATEGY: Entry terms associated with the MeSH terms "endometrioma," "laparoscopy," and "ovarian reserve" were used to search databases for articles published up to April 3, 2017, in English, Spanish, Portuguese, French, and Italian. SELECTION CRITERIA: Randomized controlled trials comparing the 3-month postoperative serum anti-Müllerian hormone (AMH) level in premenopausal women undergoing laparoscopic stripping with bipolar hemostasis or non-thermal hemostasis methods were selected. DATA COLLECTION AND ANALYSIS: Data were extracted by two independent reviewers and a meta-analysis was performed. MAIN RESULTS: Three studies met the inclusion criteria; overall, 105 patients underwent surgery with bipolar electrocoagulation and 105 patients underwent surgery with an alternative hemostasis method. The AMH level 3 months after surgery was decreased in the bipolar electrocoagulation group (mean difference -0.79 ng/mL, 95% confidence interval -1.19 to -0.39). CONCLUSIONS: Bipolar electrocoagulation negatively impacts ovarian reserve and should be avoided, especially for patients with reproductive goals.

Importância do diagnóstico por imagem em pacientes com sangramento uterino anormal / Importance of diagnostic imaging in patients with abnormal uterine bleeding

O sangramento uterino anormal é diagnóstico sindrômico comum no consultório do ginecologista e pode comprometer substancialmente a qualidade de vida. O objetivo no diagnóstico de sangramento uterino anormal é distinguir pacientes com causas estruturais (anatômicas), como pólipo, adenomiose, leiomioma, malignidade e hiperplasia, de pacientes que apresentam anatomia normal, nas quais o sangramento pode ser devido a alteração dos mecanismos de coagulação, distúrbios ovulatórios, distúrbios primários do endométrio, iatrogenia, ou ter outra causa não classificada. O diagnóstico se inicia a partir de anamnese detalhada e exame físico geral e ginecológico completos, seguidos da solicitação de exames complementares (laboratoriais e de imagem), conforme indicado. O exame de imagem de primeira linha para identificação das causas estruturais inclui a ultrassonografia pélvica. Histerossonografia, histeroscopia, ressonância magnética e amostragem endometrial para exame de anatomia patológica são opções que podem ser incluídas no diagnóstico a depender da necessidade. O objetivo deste artigo é apresentar a relevância dos exames de imagem na investigação das causas de sangramento uterino anormal.

Abnormal uterine bleeding is one of the commonest presenting complaints encountered in a gynecologist's office and may substantially affect quality of life. The aim in the diagnosis of abnormal uterine bleeding is to distinguish women with anatomic causes such as polyp, adenomyosis, leiomyoma, malignancy and hyperplasia from women with normal anatomy where the cause may be coagulopathy, ovulatory disorders, endometrial, iatrogenic and not otherwise classified. Diagnosis begins with a thorough history and physical examination followed by appropriate laboratory and imaging tests as indicated. The primary imaging test for the identification of anatomic causes include ultrasonography. Saline infusion sonohysterography, magnetic resonance, hysteroscopy, endometrial sampling are options that can be included in the diagnosis depending on the need. The aim of this article is to present the relevance of imaging exams in the investigation of the causes of abnormal uterine bleeding.

Chronic pain treatment with spinal cord neurostimulation.

The Guidelines Project, an initiative of the Brazilian Medical Association, aims to combine information from the medical field in order to standardize producers to assist the reasoning and decision-making of doctors. The information provided through this project must be assessed and criticized by the physician responsible for the conduct that will be adopted, depending on the conditions and the clinical status of each patient.

Does bisphenol A (BPA) participates in the pathogenesis of Polycystic Ovary Syndrome (PCOS)?

Abstract PCOS is an endocrine disorder characterized by chronic anovulation, hyperandrogenism, and polycystic ovaries. Its etiology is uncertain. It is debated whether BPA would be a component of the environmental factor in the etiology of PCOS. Contamination by BPA can occur from food packaging (exposure during the diet) and through skin absorption and/or inhalation. It can be transferred to the fetus via the placenta or to the infant via breast milk, and it can be found in follicular fluid, fetal serum, and amniotic fluid. The phenolic structure of BPA allows it to interact with Estrogen Receptors (ERs) through genomic signaling, in which BPA binds to nuclear ERα or Erβ, or through nongenomic signaling by binding to membrane ERs, prompting a rapid and intense response. With daily and constant exposure, BPA's tendency to bioaccumulate and its ability to activate nongenomic signaling pathways can alter women's metabolic and reproductive function, leading to hyperandrogenism, insulin resistance, obesity, atherogenic dyslipidemia, chronic inflammatory state, and anovulation and favoring PCOS. The harmful changes caused by BPA can be passed on to future generations without the need for additional exposure because of epigenetic modifications. Not only high BPA levels can produce harmful effects, but at low levels, BPA may be harmful when exposure occurs during the most vulnerable periods, such as the fetal and neonatal periods, as well as during the prepubertal age causing an early accumulation of BPA in the body. Learning how BPA participates in the pathogenesis of PCOS poses a challenge and further studies should be conducted.

Melatonin and the cardiovascular system in animals: systematic review and meta-analysis

Melatonin, a hormone released by the pineal gland, demonstrates several effects on the cardiovascular system. Herein, we performed a systematic review and meta-analysis to verify the effects of melatonin in an experimental model of myocardial infarction. We performed a systematic review according to PRISMA recommendations and reviewed MEDLINE, Embase, and Cochrane databases. Only articles in English were considered. A systematic review of the literature published between November 2008 and June 2019 was performed. The meta-analysis was conducted using the RevMan 5.3 program provided by the Cochrane Collaboration. In total, 858 articles were identified, of which 13 were included in this review. The main results of this study revealed that melatonin benefits the cardiovascular system by reducing infarct size, improving cardiac function according to echocardiographic and hemodynamic analyses, affords antioxidant effects, improves the rate of apoptosis, decreases lactate dehydrogenase activity, enhances biometric analyses, and improves protein levels, as analyzed by western blotting and quantitative PCR. In the meta-analysis, we observed a statistically significant decrease in infarct size (mean difference [MD], -20.37 [-23.56, -17.18]), no statistical difference in systolic pressure (MD, -1.75 [-5.47, 1.97]), a statistically significant decrease in lactate dehydrogenase in animals in the melatonin group (MD, -4.61 [-6.83, -2.40]), and a statistically significant improvement in the cardiac ejection fraction (MD, -8.12 [-9.56, -6.69]). On analyzing potential bias, we observed that most studies presented a low risk of bias; two parameters were not included in the analysis, and one parameter had a high risk of bias. Melatonin exerts several effects on the cardiovascular system and could be a useful therapeutic target to combat various cardiovascular diseases.

Ultrasound in the first trimester of pregnancy

The Guidelines Project, an initiative of the Brazilian Medical Association, aims to combine information from the medical field in order to standardize producers to assist the reasoning and decision-making of doctors. The information provided through this project must be assessed and criticized by the physician responsible for the conduct that will be adopted, depending on the conditions and the clinical status of each patient.