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1.
Cureus ; 14(9): e29072, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36249639

RESUMO

Glaucoma is one of the leading causes of blindness in the world. It is an ocular disorder that may have multiple etiologies and which can present as optic neuropathy and increased intraocular pressure (IOP), but in some cases like normotensive glaucoma, the IOP may remain normal. Its gradually progressive nature makes it important for early diagnosis; although the loss of vision is slow, lost vision can't be restored. Glaucoma drainage implant surgeries are an increasingly popular option in recent days in complicated cases of glaucoma where the previous trabeculectomy had failed and medical management was not responsive. Glaucoma drainage devices (GDD) are of various designs; they are implanted according to the patient condition and surgeons' preference. There are complications after the implantation of a GDD like hypotony, endophthalmitis, migration of the plate, extrusion, erosion of the mucous membrane, etc. In the market, there are various drainage devices present, but some of them are frequently used and popular. In this article, we will discuss some most commonly used GDDs and their complications. Among these, four are the most popular: Molteno, Baerveldt, Krupin, and Ahmed. The failure rate of the GDD is low. In many studies, it has been noted that only half of the GDD remains functional after five years. Therefore, further studies are still being conducted to refine the biomaterials, techniques, and shape of the GDD. The technique of surgery is also very much crucial in the success of GDD implantation. The glaucoma type is an essential factor in deciding the treatment, and the outcome of the surgery also depends on it.

2.
Eur Urol ; 79(6): 826-836, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33573862

RESUMO

BACKGROUND: Little is known about the role of the genitourinary and gastrointestinal microbiota in the pathogenesis of male infertility. OBJECTIVE: To compare the taxonomic and functional profiles of the gut, semen, and urine microbiomes of infertile and fertile men. DESIGN, SETTING, AND PARTICIPANTS: We prospectively enrolled 25 men with primary idiopathic infertility and 12 healthy men with proven paternity, and we collected rectal swabs, semen samples, midstream urine specimens, and experimental controls. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: We performed comprehensive semen analysis, 16S rRNA sequencing for quantitative high-resolution taxonomy, and shotgun metagenomics with a median of 140 million reads per sample for functional metabolic pathway profiling. RESULTS AND LIMITATIONS: We identified a diverse semen microbiome with modest similarity to the urinary microbiome. Infertile men harbored increased seminal α-diversity and distinct ß-diversity, increased seminal Aerococcus, and decreased rectal Anaerococcus. Prevotella abundance was inversely associated with sperm concentration, and Pseudomonas was directly associated with total motile sperm count. Vasectomy appeared to alter the seminal microbiome, suggesting a testicular or epididymal contribution. Anaerobes were highly over-represented in the semen of infertile men with a varicocele, but oxidative stress and leukocytospermia were associated with only subtle differences. Metagenomics data identified significant alterations in the S-adenosyl-L-methionine cycle, which may play a multifaceted role in the pathogenesis of infertility via DNA methylation, oxidative stress, and/or polyamine synthesis. CONCLUSIONS: This pilot study represents the first comprehensive investigation into the microbiome in male infertility. These findings provide the foundation for future investigations to explore causality and identify novel microbiome-based diagnostics and therapeutics for men with this complex and emotionally devastating disease. PATIENT SUMMARY: We explored the resident populations of bacteria living in the gut, semen, and urine of infertile and fertile men. We found several important bacterial and metabolic pathway differences with the potential to aid in diagnosing and treating male infertility in the future.


Assuntos
Disbiose , Infertilidade Masculina , Microbiota , Humanos , Infertilidade Masculina/diagnóstico , Infertilidade Masculina/genética , Masculino , Projetos Piloto , RNA Ribossômico 16S/genética , Sêmen , Motilidade dos Espermatozoides
4.
Endocr Pract ; 25(6): 605-611, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30865532

RESUMO

Objective: Preservation of parathyroid function is one of the primary tenets of endocrine surgery. For patients with thyroid disease, an inadvertently compromised parathyroid gland is routinely autotransplanted into the neck at the time of surgery. By contrast, for patients with parathyroid disease secondary to hyperplasia, the timing of auto-transplantation needs to be further considered in order to balance the risks between persistent disease and permanent hypocalcemia. Cryopreservation preserves cellular function and permits the storage of parathyroid tissue for potential re-implantation at a later date in patients who develop hypoparathyroidism. Methods: In this paper, we review the process of cryopreservation, with particular emphasis on the regulatory issues involved in establishing a local service, tissue processing, billing and reimbursements, outcome (functionality), and complications. Results: A detailed description of the technique as performed at our institution is described and illustrated. Conclusion: Cryopreservation affords surgical insurance against the disastrous sequelae of permanent hypoparathyroidism. Our techniques are easy to adopt with only a modest initial investment of time and money, particularly for institutions that already cryopreserve other tissue types. Abbreviations: PTH = parathyroid hormone; RMPI = Roswell Park Memorial Institute; RPMI-SSS = RPMI-serum substitute supplement.


Assuntos
Hipocalcemia , Glândulas Paratireoides , Criopreservação , Humanos , Hipoparatireoidismo , Hormônio Paratireóideo , Tireoidectomia , Transplante Autólogo
5.
Urology ; 85(6): 1339-45, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26099879

RESUMO

OBJECTIVE: To compare cryosurvival rates between remote collections with NextGen kit (offsite) and onsite collection of semen samples from infertile men and those with cancer. METHODS: Prefreeze and post-thaw sperm motility, total motile sperm, and percent cryosurvival rates were compared between samples collected from infertile men onsite at the Andrology Center (n = 10) and samples collected from infertile patients at home (offsite; n = 9), which were shipped by NextGen to our laboratory. A second group (n = 17) consisted of 10 semen samples from cancer patients collected onsite, which were compared with 7 semen samples from cancer patients shipped by the NextGen. All semen samples were assessed within 18 hours of collection. RESULTS: In the infertile men, percent cryosurvival rates were similar with NextGen compared with those of onsite collection (53.14 ± 28.9% vs 61.90 ± 20.46%; P = .51). Similarly, in the cancer patients, all 4 parameters were comparable between the onsite and NextGen. Cryosurvival rates were also similar between NextGen compared with those of onsite collection (52.71 ± 20.37% vs 58.90 ± 22.68%; P = .46). CONCLUSION: Cancer patients can bank sperm as effectively as men banking for infertility reasons using the NextGen kit.


Assuntos
Criopreservação , Análise do Sêmen , Preservação do Sêmen , Manejo de Espécimes/métodos , Bancos de Esperma , Humanos , Infertilidade Masculina , Masculino , Neoplasias
6.
Cardiovasc Ther ; 33(4): 155-60, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25892271

RESUMO

BACKGROUND: Early intervention is certainly a preferred strategy over conservative management in patients with post-infarction angina (PIA). But at times, it may not be feasible to intervene, especially if patient refuses for intervention. In a pilot study, we analyzed whether the addition of eptifibatide to intensified antianginal therapy would be of added benefit, in patients with PIA not willing to undergo intervention. METHODS: A total of 461 patients with PIA who refused intervention were randomized in a 1:1 manner to receive either eptifibatide along with intensification of antianginal therapy (group A; n = 229) or intensified antianginal therapy alone (group B; n = 232). The primary endpoints were composite of all-cause death and nonfatal myocardial infarction at 30 days. RESULTS: Primary composite endpoint did not differ between the two groups (16.2% vs. 18.9% in group A and group B, odds ratio [OR], 0.82; 95% CI, 0.5-1.30; P-value = 0.43). Significant earlier relief of angina (complete relief of angina within 12 h: 76% of patients in group A vs. 40.5% in group B; P-value <0.0001) was achieved in group A compared to group B. Although on Bleeding Academic Research Consortium (BARC) scale, type 1 and 2 bleeding was higher in group A (OR, 3.18; 95% CI, 1.76-5.74; P-value = 0.0001), the more serious (composite of type 3 and 5) bleeds did not show any difference (OR, 1.73; 95% CI, 0.7-4.08; P-value = 0.21). CONCLUSION: In patients with PIA who refused intervention, eptifibatide infusion resulted in earlier relief of angina albeit at the cost of increased non-life-threatening bleeding. Further, this effect was achieved in significantly higher number of patients receiving eptifibatide infusion when compared to patients not receiving it. Primary composite endpoints, however, did not differ in two groups, but being a pilot study, this needs to be confirmed by larger study of adequate sample size.


Assuntos
Angina Pectoris/tratamento farmacológico , Infarto do Miocárdio/terapia , Peptídeos/uso terapêutico , Intervenção Coronária Percutânea , Inibidores da Agregação Plaquetária/uso terapêutico , Recusa do Paciente ao Tratamento , Adulto , Angina Pectoris/diagnóstico , Angina Pectoris/etiologia , Angina Pectoris/mortalidade , Intervalo Livre de Doença , Eptifibatida , Feminino , Hemorragia/induzido quimicamente , Humanos , Índia , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/complicações , Infarto do Miocárdio/diagnóstico , Infarto do Miocárdio/mortalidade , Razão de Chances , Peptídeos/efeitos adversos , Projetos Piloto , Inibidores da Agregação Plaquetária/efeitos adversos , Estudos Prospectivos , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento
7.
Heart Asia ; 7(1): 29-31, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-27326210

RESUMO

BACKGROUND: The association of congenital heart disease (CHD) with malformations of the gastrointestinal (GI) tract/abdominal wall is known. The rates of cardiac malformations reported in previous studies of these anomalies are highly variable. OBJECTIVE: To find the prevalence and pattern of CHD in patients with major gastrointestinal malformations (anorectal malformations, oesophageal atresia/tracheo-oesophageal fistula, and omphalocoele) undergoing surgery at a tertiary care hospital in India. METHODS: From July 2012 to December 2013, 43 patients (34 (79%) male, 9 (21%) female) were evaluated by clinical examination, ECG, chest radiography, and colour Doppler echocardiography. RESULTS: Of the 43 patients, 26 (60.46%) had CHD. The most common GI malformation was anorectal malformation: 32 cases (74.41%), of whom 16 (50%) had CHD. The second most common malformation was oesophageal atresia/tracheo-oesophageal fistula: 5 cases (11.62%), all (100%) with CHD. The third group comprised patients with omphalocoele: 4 cases (9.3%), 3 of whom (75%) had CHD. The fourth group comprised patients with VACTERAL (vertebral anomalies, anal atresia, cardiovascular malformations, tracheo-oesophageal fistula, renal and limb anomalies) association-2 cases (4.6%), all (100%) with CHD. The most common CHD was isolated atrial septal defect (ASD) (73%), followed by ASD + ventricular septal defect (VSD) + patent ductus arteriosus (PDA) (7.6%), ASD + VSD (3.8%), ASD + PDA (3.8%), VSD (3.8%), PDA (3.8%), and coarctation of the aorta (3.8%). CONCLUSIONS: We found the frequency of CHD in patients with GI malformations was very high, the most common presentation being ASD. Our study indicates the need for larger scale studies to determine the prevalence of CHD in patients with GI malformations in the Indian population.

8.
Biomed Res Int ; 2014: 916212, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24900998

RESUMO

Endometriosis, PCOS, and unexplained infertility are currently the most common diseases rendering large numbers of women infertile worldwide. Oxidative stress, due to its deleterious effects on proteins and nucleic acids, is postulated to be the one of the important mechanistic pathways in differential expression of proteins and in these diseases. The emerging field of proteomics has allowed identification of proteins involved in cell cycle, as antioxidants, extracellular matrix (ECM), cytoskeleton, and their linkage to oxidative stress in female infertility related diseases. The aim of this paper is to assess the association of oxidative stress and protein expression in the reproductive microenvironments such as endometrial fluid, peritoneal fluid, and follicular fluid, as well as reproductive tissues and serum. The review also highlights the literature that proposes the use of the fertility related proteins as potential biomarkers for noninvasive and early diagnosis of the aforementioned diseases rather than utilizing the more invasive methods used currently. The review will highlight the power of proteomic profiles identified in infertility related disease conditions and their linkage with underlying oxidative stress. The power of proteomics will be reviewed with regard to eliciting molecular mechanisms for early detection and management of these infertility related conditions.


Assuntos
Biomarcadores/metabolismo , Infertilidade Feminina/metabolismo , Estresse Oxidativo/fisiologia , Proteoma/metabolismo , Líquido Ascítico , Endométrio , Feminino , Líquido Folicular/metabolismo , Humanos , Proteômica/métodos , Reprodução
9.
Reprod Biol Endocrinol ; 10: 49, 2012 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-22748101

RESUMO

Oxidative stress (OS), a state characterized by an imbalance between pro-oxidant molecules including reactive oxygen and nitrogen species, and antioxidant defenses, has been identified to play a key role in the pathogenesis of subfertility in both males and females. The adverse effects of OS on sperm quality and functions have been well documented. In females, on the other hand, the impact of OS on oocytes and reproductive functions remains unclear. This imbalance between pro-oxidants and antioxidants can lead to a number of reproductive diseases such as endometriosis, polycystic ovary syndrome (PCOS), and unexplained infertility. Pregnancy complications such as spontaneous abortion, recurrent pregnancy loss, and preeclampsia, can also develop in response to OS. Studies have shown that extremes of body weight and lifestyle factors such as cigarette smoking, alcohol use, and recreational drug use can promote excess free radical production, which could affect fertility. Exposures to environmental pollutants are of increasing concern, as they too have been found to trigger oxidative states, possibly contributing to female infertility. This article will review the currently available literature on the roles of reactive species and OS in both normal and abnormal reproductive physiological processes. Antioxidant supplementation may be effective in controlling the production of ROS and continues to be explored as a potential strategy to overcome reproductive disorders associated with infertility. However, investigations conducted to date have been through animal or in vitro studies, which have produced largely conflicting results. The impact of OS on assisted reproductive techniques (ART) will be addressed, in addition to the possible benefits of antioxidant supplementation of ART culture media to increase the likelihood for ART success. Future randomized controlled clinical trials on humans are necessary to elucidate the precise mechanisms through which OS affects female reproductive abilities, and will facilitate further explorations of the possible benefits of antioxidants to treat infertility.


Assuntos
Estresse Oxidativo/fisiologia , Reprodução/fisiologia , Animais , Antioxidantes/metabolismo , Antioxidantes/farmacologia , Antioxidantes/uso terapêutico , Endometriose/tratamento farmacológico , Endometriose/metabolismo , Feminino , Radicais Livres/metabolismo , Humanos , Infertilidade Feminina/tratamento farmacológico , Infertilidade Feminina/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Gravidez , Espécies Reativas de Oxigênio/metabolismo , Reprodução/efeitos dos fármacos , Comportamento de Redução do Risco
10.
Anal Quant Cytol Histol ; 34(1): 23-7, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22590816

RESUMO

OBJECTIVE: To evaluate peritoneal fluid hemosiderin-laden macrophages (H-LMs) in patients with endometriosis compared to controls. STUDY DESIGN: Consecutive series of 46 patients during a year undergoing laparoscopy for benign gynecologic conditions were included. The presence of H-LMs in peritoneal fluid was evaluated. We compared clinical factors in patients with or without endometriosis in respect to H-LM status. To assess the potential of H-LMs to diagnose endometriosis, the sensitivity and specificity were calculated. RESULTS: Patients with endometriosis were significantly more likely to have positive H-LM test results than controls (p = 0.0013). The presence of H-LM has a low sensitivity of 52% but an acceptable specificity of 87% in diagnosing endometriosis. The presence of H-LMs was not related with any other of the clinical factors studied. CONCLUSION: The presence of specific findings of H-LMs related to endometriosis strongly suggests abnormalities in peritoneal iron metabolism.


Assuntos
Líquido Ascítico/patologia , Endometriose/diagnóstico , Hemossiderina/análise , Macrófagos/química , Adulto , Biópsia , Endometriose/patologia , Feminino , Humanos , Macrófagos/patologia , Sensibilidade e Especificidade
11.
J Oncol ; 2011: 475983, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21577260

RESUMO

This paper reviews current screening techniques as well as novel biomarkers and their potential role in early detection of ovarian cancer. Ovarian cancer is one of the most common reproductive cancers and has the highest mortality rate amongst gynecologic cancers. Because most ovarian cancer diagnoses occur in the late stages of the disease, five-year survival rates fall below 20%. To improve survival rates and to lower mortality rates for ovarian cancer, improved detection at early stages of the disease is needed. Current screening approaches include tumor markers, ultrasound, or a combination. Efforts are underway to discover new biomarkers of ovarian cancer in order to surmount the obstacles in early-stage diagnosis. Among serum protein markers, HE4 and mesothelin can augment CA125 detection providing higher sensitivity and specificity due to the presence of these proteins in early-stage ovarian cancer. Detection testing that includes methylation of the MCJ gene and increased expression of vascular endothelial growth factor is correlated to poor prognosis and may predict patient survival outcome. Detection testing of biomarkers with long-term stability and combination panels of markers, will likely lead to effective screening strategies with high specificity and sensitivity for early detection of ovarian cancer.

12.
Antioxid Redox Signal ; 10(8): 1375-403, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18402550

RESUMO

Physiological levels of reactive oxygen species (ROS) play an important regulatory role through various signaling transduction pathways in folliculogenesis, oocyte maturation, endometrial cycle, luteolysis, implantation, embryogenesis, and pregnancy. Persistent and elevated generation of ROS leads to a disturbance of redox potential that in turn causes oxidative stress (OS). Our literature review captures the role of ROS in modulating a range of physiological functions and pathological processes affecting the female reproductive life span and even thereafter (i.e., menopause). The role of OS in female reproduction is becoming increasingly important, as recent evidence suggest that it plays a part in conditions such as polycystic ovarian disease, endometriosis, spontaneous abortions, preeclampsia, hydatidiform mole, embryopathies, preterm labor, and intrauterine growth retardation. OS has been implicated in different reproductive scenarios and is detrimental to both natural and assisted fertility. Many extrinsic and intrinsic conditions exist in assisted reproduction settings that can be tailored to reduce the toxic effects of ROS. Laboratory personnel should avoid procedures that are known to be deleterious, especially when safer procedures that can prevent OS are available. Although antioxidants such as folate, zinc, and thiols may help enhance fertility, the available data are contentious and must be evaluated in controlled studies with larger populations.


Assuntos
Estresse Oxidativo/fisiologia , Reprodução/fisiologia , Animais , Feminino , Humanos , Masculino , Modelos Biológicos , Oxirredução , Gravidez , Espécies Reativas de Oxigênio/metabolismo
13.
Fertil Steril ; 88(5): 1273-84, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17991514

RESUMO

Female sexual dysfunction is a prevalent problem in the general community; however, it has not been studied as extensively as male sexual dysfunction. Female sexual dysfunction is a common complication after most pelvic surgeries. With the introduction of screening programs, most pelvic malignancies are detected at earlier stages and in younger patients. Sexual dysfunction is a major quality-of-life issue in these young women. Hysterectomy (simple or radical) is the most common type of pelvic surgery in women and is one of the most important causes of female sexual dysfunction. Additionally, female sexual dysfunction is an important issue after urologic (radical cystectomy) and colorectal surgeries (simple and radical proctocolectomy). Sexual dysfunction is a common problem among postmenopausal women. Modifications in the surgical technique (nerve sparing) are rapidly evolving in the field of urology and colorectal surgery, which will be soon followed by modifications in the field of gynecologic surgery. In this article we summarize the pathophysiology and classification of female sexual dysfunction, with special emphasis on the relationship between female sexual dysfunction and pelvic surgeries.


Assuntos
Disfunções Sexuais Fisiológicas/fisiopatologia , Disfunções Sexuais Fisiológicas/terapia , Gerenciamento Clínico , Feminino , Procedimentos Cirúrgicos em Ginecologia/efeitos adversos , Humanos , Disfunções Sexuais Fisiológicas/classificação , Disfunções Sexuais Fisiológicas/psicologia
14.
Obstet Gynecol Surv ; 62(5): 335-47; quiz 353-4, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17425812

RESUMO

UNLABELLED: Human reproduction is not considered a highly efficient biological process. Before the end of the first trimester, 30%-50% of conceptions end in spontaneous abortion. Most losses occur at the time of implantation. 15%-20% of clinical pregnancies end in spontaneous abortions. Recurrent pregnancy loss is a frustrating clinical problem both for clinicians and patients. Recurrent pregnancy loss affects 0.5%-3% of women in the reproductive age group, and between 50%-60% of recurrent pregnancy losses are idiopathic. Oxidative stress-induced damage has been hypothesized to play a role in spontaneous abortion, idiopathic recurrent pregnancy loss, hydatidiform mole, defective embryogenesis, and drug-induced teratogenicity. Some studies implicate systemic and placental oxidative stress in the pathophysiology of abortion and recurrent pregnancy loss. Oxidant-induced endothelial damage, impaired placental vascularization and immune malfunction have all been proposed to play a role in the pathophysiology of idiopathic recurrent pregnancy loss. Oxidative stress-induced placental dysfunction may be a common cause of the multifactorial and polygenic etiologies of abortion, recurrent pregnancy loss, defective embryogenesis, hydatidiform mole, and drug-induced teratogenic effects. Oxidative stress-induced modification of phospholipids has been linked to the formation of antiphospholipid antibodies in the antiphospholipid syndrome. The objective of this review was to examine the association between oxidative stress, spontaneous abortion and recurrent pregnancy loss, based on the published literature. We conducted an extensive literature search utilizing the databases of Medline, CINAHL, and Cochrane from 1986 to 2005. The following keywords were used: oxidative stress, abortion, recurrent pregnancy loss, reactive oxygen species, antioxidants, fetal development, and embryopathies. We conducted an electronic search, as well as a manual search of cross-references. We have included all studies in the English language found in the literature focusing on oxidative stress and its association with abortions, recurrent pregnancy loss and drug-induced teratogenicity. The role of antioxidant vitamins for primary prevention of oxidative stress-induced pathologies needs to be investigated further. TARGET AUDIENCE: Obstetricians & Gynecologists, Family Physicians. LEARNING OBJECTIVES: After completion of this article, the reader should be able to state that the causes of spontaneous and recurrent abortion are multifaceted, however, some of the causes may be preventable and also explain that the role of oxidative stress during pregnancy and adverse pregnancy outcomes has a basis in pathophysiology, although the role of oxidative stress and the treatment of oxidative stress during or before pregnancy remains speculative.


Assuntos
Aborto Habitual/etiologia , Aborto Espontâneo/etiologia , Antioxidantes/fisiologia , Estresse Oxidativo , Reprodução/fisiologia , Aborto Habitual/prevenção & controle , Aborto Espontâneo/prevenção & controle , Antioxidantes/uso terapêutico , Desenvolvimento Embrionário , Feminino , Humanos , Estresse Oxidativo/fisiologia , Gravidez , Complicações na Gravidez/etiologia , Complicações na Gravidez/prevenção & controle
15.
Curr Opin Obstet Gynecol ; 18(3): 325-32, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16735834

RESUMO

PURPOSE OF REVIEW: This review summarizes the role of free radicals and oxidative stress in the pathophysiology of human reproduction. RECENT FINDINGS: An extensive review of the literature on the role of oxidative stress in influencing assisted reproduction and its outcome is described in this article. Free radicals or reactive oxygen species mediate their action through many of the proinflammatory cytokines and this mechanism has been proposed as a common underlying factor for endometriosis, ovarian cancer, polycystic ovary disease, and various other pathologies affecting the female reproductive process, as highlighted in this review. Oxidative stress, sperm DNA damage, and apoptosis have been implicated in male infertility. Elevated reactive oxygen species levels correlate with the poor fertility outcomes seen in the assisted reproductive technology setting. SUMMARY: Oxidative stress has been implicated in male and female infertility, including fetal dysmorphogenesis, abortions, and intrauterine growth restriction. Accurate evaluation of seminal oxidative stress by standardized assays may help in the diagnosis and management of male infertility. There is evidence in the literature on the beneficial effects of oral antioxidant supplementation in male infertility. Current ongoing trials will provide answers on the safety and effectiveness of antioxidants in improving maternal and fetal outcomes. Further studies need to be conducted to determine if antioxidant supplementation will prevent fetal developmental defects in high-risk pregnancy with diabetes.


Assuntos
Radicais Livres/efeitos adversos , Infertilidade/fisiopatologia , Estresse Oxidativo/fisiologia , Gravidez/metabolismo , Reprodução/fisiologia , Antioxidantes/uso terapêutico , Feminino , Genitália Feminina/metabolismo , Genitália Feminina/fisiopatologia , Humanos , Masculino , Reprodução/efeitos dos fármacos , Técnicas de Reprodução Assistida
16.
Reprod Biol Endocrinol ; 3: 28, 2005 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-16018814

RESUMO

In a healthy body, ROS (reactive oxygen species) and antioxidants remain in balance. When the balance is disrupted towards an overabundance of ROS, oxidative stress (OS) occurs. OS influences the entire reproductive lifespan of a woman and even thereafter (i.e. menopause). OS results from an imbalance between prooxidants (free radical species) and the body's scavenging ability (antioxidants). ROS are a double-edged sword - they serve as key signal molecules in physiological processes but also have a role in pathological processes involving the female reproductive tract. ROS affect multiple physiological processes from oocyte maturation to fertilization, embryo development and pregnancy. It has been suggested that OS modulates the age-related decline in fertility. It plays a role during pregnancy and normal parturition and in initiation of preterm labor. Most ovarian cancers appear in the surface epithelium, and repetitive ovulation has been thought to be a causative factor. Ovulation-induced oxidative base damage and damage to DNA of the ovarian epithelium can be prevented by antioxidants. There is growing literature on the effects of OS in female reproduction with involvement in the pathophysiology of preeclampsia, hydatidiform mole, free radical-induced birth defects and other situations such as abortions. Numerous studies have shown that OS plays a role in the pathophysiology of infertility and assisted fertility. There is some evidence of its role in endometriosis, tubal and peritoneal factor infertility and unexplained infertility. This article reviews the role OS plays in normal cycling ovaries, follicular development and cyclical endometrial changes. It also discusses OS-related female infertility and how it influences the outcomes of assisted reproductive techniques. The review comprehensively explores the literature for evidence of the role of oxidative stress in conditions such as abortions, preeclampsia, hydatidiform mole, fetal embryopathies, preterm labour and preeclampsia and gestational diabetes. The review also addresses the growing literature on the role of nitric oxide species in female reproduction. The involvement of nitric oxide species in regulation of endometrial and ovarian function, etiopathogenesis of endometriosis, and maintenance of uterine quiescence, initiation of labour and ripening of cervix at parturition is discussed. Complex interplay between cytokines and oxidative stress in the etiology of female reproductive disorders is discussed. Oxidant status of the cell modulates angiogenesis, which is critical for follicular growth, corpus luteum formation endometrial differentiation and embryonic growth is also highlighted in the review. Strategies to overcome oxidative stress and enhance fertility, both natural and assisted are delineated. Early interventions being investigated for prevention of preeclampsia are enumerated. Trials investigating combination intervention strategy of vitamin E and vitamin C supplementation in preventing preeclampsia are highlighted. Antioxidants are powerful and there are few trials investigating antioxidant supplementation in female reproduction. However, before clinicians recommend antioxidants, randomized controlled trials with sufficient power are necessary to prove the efficacy of antioxidant supplementation in disorders of female reproduction. Serial measurement of oxidative stress biomarkers in longitudinal studies may help delineate the etiology of some of the diosorders in female reproduction such as preeclampsia.


Assuntos
Infertilidade Feminina/fisiopatologia , Estresse Oxidativo/fisiologia , Reprodução/fisiologia , Envelhecimento/fisiologia , Animais , Antioxidantes/uso terapêutico , Desenvolvimento Embrionário , Feminino , Humanos , Menopausa/fisiologia , Óxido Nítrico Sintase/fisiologia , Gravidez , Complicações na Gravidez/fisiopatologia , Espécies Reativas de Oxigênio/farmacologia , Técnicas de Reprodução Assistida
17.
Reprod Biomed Online ; 11(5): 641-50, 2005 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16409717

RESUMO

Reactive oxygen species (ROS) have a role in the modulation of gamete quality and gamete interaction. Generation of ROS is inherent in spermatozoa and contaminating leukocytes. ROS influence spermatozoa, oocytes, embryos and their environment. Oxidative stress (OS) mediates peroxidative damage to the sperm membrane and induces nuclear DNA damage. ROS can modulate the fertilizing capabilities of the spermatozoa. There is extensive literature on OS and its role in male infertility and sperm DNA damage and its effects on assisted reproductive techniques. Evidence is accumulating on the role of ROS in female reproduction. Many animal and human studies have elucidated a role for ROS in oocyte development, maturation, follicular atresia, corpus luteum function and luteolysis. OS-mediated precipitation of pathologies in the female reproductive tract is similar to those involved in male infertility. OS influences the oocyte and embryo quality and thus the fertilization rates. ROS appears to play a significant role in the modulation of gamete interaction and also for successful fertilization to take place. ROS in culture media may impact post-fertilization development, i.e. cleavage rate, blastocyst yield and quality (indicators of assisted reproduction outcomes). OS is reported to affect both natural and assisted fertility. Antioxidant strategies should be able to intercept both extracellular and intracellular ROS. This review discusses the sources of ROS in media used in IVF-embryo transfer and strategies to overcome OS in oocyte in-vitro maturation, in-vitro culture and sperm preparation techniques.


Assuntos
Transferência Embrionária , Fertilização in vitro , Infertilidade Feminina/etiologia , Infertilidade Feminina/terapia , Estresse Oxidativo/fisiologia , Espécies Reativas de Oxigênio/metabolismo , Antioxidantes/farmacologia , Corpo Lúteo/metabolismo , Meios de Cultura/química , Técnicas de Cultura Embrionária/normas , Transferência Embrionária/normas , Endometriose/metabolismo , Endométrio/metabolismo , Feminino , Fertilização/fisiologia , Fertilização in vitro/normas , Humanos , Folículo Ovariano/metabolismo , Oxirredução , Estresse Oxidativo/efeitos dos fármacos
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