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Search Results: 1 - 10 of 220193 matches for " C.; Esteves "
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A Critical Appraisal on the Role of Varicocele in Male Infertility
Ricardo Miyaoka,Sandro C. Esteves
Advances in Urology , 2012, DOI: 10.1155/2012/597495
Abstract: Varicocele is a major cause of male infertility, as it may impair spermatogenesis through several distinct physiopathological mechanisms. With the recent advances in biomolecular techniques and the development of novel sperm functional tests, it has been possible to better understand the mechanisms involved in testicular damage provoked by varicocele and, therefore, propose optimized ways to prevent and/or reverse them. Up to now, there is still controversy involving the true benefit of varicocele repair in subfertile men as well as in certain specific situations such as concomitant contralateral subclinical varicocele or associated nonobstructive azoospermia. Also, with the continued development of assisted reproductive technology new issues and questions are emerging regarding the role of varicocelectomy in this context. This paper reviews the most recent data available on the pathogenesis, diagnosis, and management of varicocele with regard to male infertility. 1. Introduction Approximately 8% of men in reproductive age seek medical assistance for fertility-related problems. Among them, 1%–10% carry a condition that compromise their fertility potential and varicocele alone accounts for 35% of these cases [1, 2]. Our personal database of a referral tertiary center for male reproduction presents an incidence of 21.9% of varicocele in 2,875 analyzed subjects [3]. While varicocele has an incidence of 4.4%–22.6% in the general population, 21%–41% of men with primary infertility and 75%–81% of those with secondary infertility have this condition [4, 5]. The impact of varicocele on male fertility was not suspected until the end of the 19th century, when occlusion of dilated veins from the pampiniform plexus was shown to improve semen quality [4, 6]. MacLeod in 1965 demonstrated decreased sperm count, decreased motility and higher prevalence of abnormal forms in semen specimens collected from infertile men with varicocele [7]. Although the physiopathology of varicocele and its relationship with male infertility has been discussed for the last 50 years, the exact mechanisms that would ultimately lead to an infertile/subfertile state are still controversial. Even more debatable is the true benefit from its surgical repair [8, 9]. Treating male factor infertility should have as its ultimate goal to achieve a live birth. However, efforts must be made to maximize the couple’s fertility potential. In this sense, it is argued that varicocele treatment may be critical to restore or optimize testicular function. We present a review on the current concepts and
Novel concepts in male infertility
Esteves, Sandro C.;Agarwal, Ashok;
International braz j urol , 2011, DOI: 10.1590/S1677-55382011000100002
Abstract: extraordinary advances have been achieved in the field of male infertility in the last decades. there are new concepts in sperm physiology and several modern tools for the assessment of spermatogenesis kinetics in vivo. new tests using molecular biology and dna damage assays allow the clinician to correctly diagnose men so far classified as having idiopathic male infertility. in the field of treatment, microsurgery has increased success rates either for reconstruction of the reproductive tract or the retrieval of spermatozoa for assisted conception. emerging evidence suggests that life-style and environmental conditions are of utmost importance in male fertility and subfertility. this review discusses several concepts that have changed over the last years, such as the duration of the spermatogenic cycle in humans, y-chromosome infertility, the reproductive potential of non-mosaic klinefelter syndrome men, the impact of paternal age and sperm dna in male infertility, the role of antioxidants in the treatment of infertile men, the predictive factors and techniques for sperm retrieval in non-obstructive azoospermia, and the microsurgical treatment of clinical varicoceles. whenever possible, levels of evidence are provided as suggested by the oxford center of evidence-based medicine.
Recovery of spermatogenesis after microsurgical subinguinal varicocele repair in azoospermic men based on testicular histology
Esteves, Sandro C.;Glina, Sidney;
International braz j urol , 2005, DOI: 10.1590/S1677-55382005000600005
Abstract: objective: analyze whether testicular histologic patterns from a group of azoospermic men with varicocele is predictive of treatment outcome after subinguinal microsurgical varicocele repair. materials and methods: seventeen azoospermic men underwent bilateral open single testis biopsy and microsurgical subinguinal repair of clinical varicoceles. results: histopathology of testicular biopsies revealed hypospermatogenesis (hypo) in 6 men, maturation arrest (ma) in 5, and sertoli cell-only (sco) in 6. overall, presence of spermatozoa in the ejaculates was achieved in 47% (8/17) of men after varicocele repair, but only 35% (6/17) of them had motile sperm in their ejaculates. only men with testicular histology revealing hypo (5/6) or maturation arrest (3/5) had improvement after surgery. median (25% - 75% percentile) postoperative motile sperm count for both groups were 0.9 x 106/ml (0.1-1.8 x 106/ml) and 0.7 x 106/ml (0.1-1.1), respectively (p = 0.87). the mean time for appearance of spermatozoa in the ejaculates was 5 months (3 to 9 months). one (hypo) of 8 (12.5%) men who improved after surgery contributed to an unassisted pregnancy. postoperative testicular biopsies obtained from patients who had no improvement after surgery revealed that testicular histology diagnosis remained unchanged. successful testicular sperm retrieval for intracytoplasmic sperm injection (icsi) was achieved in 4 of 9 (44.4%) individuals who did not improve after surgery, including 1 man with testicular histology exhibiting sco. conclusion: microsurgical varicocele repair in nonobstructive azoospermic men with clinical varicoceles can result in sperm appearance in the ejaculate when hypospermatogenesis or maturation arrest is found on testicular histology diagnosis.
Sperm retrieval techniques for assisted reproduction
Esteves, Sandro C.;Miyaoka, Ricardo;Agarwal, Ashok;
International braz j urol , 2011, DOI: 10.1590/S1677-55382011000500002
Abstract: different surgical methods such as pesa, mesa, tesa, tese and micro-tese have been developed to retrieve spermatozoa from either the epididymis or the testis according to the type of azoospermia, i.e., obstructive or non-obstructive. laboratory techniques are used to remove contaminants, cellular debris, and red blood cells following collection of the epididymal fluid or testicular tissue. surgically-retrieved spermatozoa may be used for intracytoplasmic sperm injection (icsi) and/or cryopreservation. in this article, we review the surgical procedures for retrieving spermatozoa from both the epididymis and the testicle and provide technical details of the commonly used methods. a critical analysis of the advantages and limitations of the current surgical methods to retrieve sperm from males with obstructive and non-obstructive azoospermia is presented along with an overview of the laboratory techniques routinely used to process surgically-retrieved sperm. lastly, we summarize the results from the current literature of sperm retrieval, as well as the clinical outcome of icsi in the clinical scenario of obstructive and non-obstructive azoospermia.
Feasibility of refreezing human spermatozoa through the technique of liquid nitrogen vapor
Verza Jr, Sidney;Esteves, Sandro C.;
International braz j urol , 2004, DOI: 10.1590/S1677-55382004000600006
Abstract: objective: to assess the feasibility of refreezing human semen using the technique of liquid nitrogen vapor with static phases. materials and methods: twenty samples from 16 subjects who required disposal of their cryopreserved semen were thawed, corresponding to 6 cancer patients and 10 participants in the assisted reproduction (ar) program. samples were refrozen using the technique of liquid nitrogen vapor with static phases, identical to the one used for the initial freezing, and thawed again after 72 hours. we assessed the concentration of motile spermatozoa, total and progressive percent motility and spermatic vitality, according to criteria of the world health organization (who), as well as spermatic morphology according to the strict kruger criterion, after the first and after the second thawing. results: we observed a significant decrease in all the parameters evaluated between the first and the second thawing. median values for the concentration of motile spermatozoa decreased from 2.0x106/ml to 0.1x106/ml (p < 0.01); total percent motility from 42% to 22.5% (p < 0.01); progressive percent motility from 34% to 9.5% (p < 0.01); vitality from 45% to 20% (p < 0.01); and morphology from 5% to 5% (p = 0.03). there was no significant difference in the spermatic parameters between the cancer and assisted reproduction groups, both after the first and after the second thawing. we observed that in 100% of cases there was retrieval of motile spermatozoa after the second thawing. conclusions: refreezing of human semen by the technique of liquid nitrogen vapor allows the retrieval of viable spermatozoa after thawing.
Sperm defect severity rather than sperm source is associated with lower fertilization rates after intracytoplasmic sperm injection
Verza Jr, Sidney;Esteves, Sandro C.;
International braz j urol , 2008, DOI: 10.1590/S1677-55382008000100008
Abstract: objective: to evaluate the impact of sperm defect severity and the type of azoospermia on the outcomes of intracytoplasmic sperm injection (icsi). materials and methods: this study included 313 icsi cycles that were divided into two major groups according to the source of spermatozoa used for icsi: 1) ejaculated (group 1; n = 220) and 2) testicular/epididymal (group 2; n = 93). group 1 was subdivided into four subgroups according to the results of the semen analysis: 1) single defect (oligo-[o] or astheno-[a] or teratozoospermia-[t], n = 41), 2) double defect (a combination of two single defects, n = 45), 3) triple defect (oat, n = 48), and 4) control (no sperm defects; n = 86). group 2 was subdivided according to the type of azoospermia: 1) obstructive (oa: n = 39) and 2) non-obstructive (noa: n = 54). fertilization (2pn), cleavage, embryo quality, clinical pregnancy and miscarriage rates were statistically compared using one-way anova and chi-square analyses. results: significantly lower fertilization rates were obtained when either ejaculated sperm with triple defect or testicular sperm from noa patients (63.4 + 25.9% and 52.2 + 29.3%, respectively) were used for icsi as compared to other groups (~73%; p < 0.05). epididymal and testicular spermatozoa from oa patients fertilized as well as normal or mild/moderate deficient ejaculated sperm. cleavage, embryo quality, pregnancy and miscarriage rates did not differ statistically between ejaculated and obstructive azoospermia groups. however, fertilization, cleavage and pregnancy rates were significantly lower for noa patients. conclusion: lower fertilization rates are achieved when icsi is performed with sperm from men with oligoasthenoteratozoospermic and non-obstructive azoospermic, and embryo development and pregnancy rates are significantly lower when testicular spermatozoa from noa men are used.
Surgical treatment of male infertility in the era of intracytoplasmic sperm injection - new insights
Esteves, Sandro C.;Miyaoka, Ricardo;Agarwal, Ashok;
Clinics , 2011, DOI: 10.1590/S1807-59322011000800026
Abstract: assisted reproductive technology is an evolving area, and several adjuvant procedures have been created to increase a couple's chance of conceiving. for male infertility, the current challenges are to properly accommodate old and new techniques that are both cost-effective and evidence-based. in this context, urologists are expected to diagnose, counsel, provide medical or surgical treatment whenever possible and/or correctly refer male patients for assisted conception. urologists are sometimes part of a multiprofessional team in an assisted reproduction unit and are responsible for the above-cited tasks as well as the surgical retrieval of sperm from either the epididymides or testicles. we present a comprehensive review of the surgical treatment options for infertile males, including the perioperative planning and prognostic aspects, with an emphasis on the role of microsurgery in the optimization of treatment results. this review also discusses current techniques for sperm retrieval that are used in association with assisted reproductive technology and includes sperm retrieval success rates according to the technique and the type of azoospermia. new insights are provided with regard to each surgical treatment option in view of the availability of assisted conception to overcome male infertility.
An update on the clinical assessment of the infertile male
Esteves, Sandro C.;Miyaoka, Ricardo;Agarwal, Ashok;
Clinics , 2011, DOI: 10.1590/S1807-59322011000400026
Abstract: male infertility is directly or indirectly responsible for 60% of cases involving reproductive-age couples with fertility-related issues. nevertheless, the evaluation of male infertility is often underestimated or postponed. a coordinated evaluation of the infertile male using standardized procedures improves both diagnostic precision and the results of subsequent management in terms of effectiveness, risk and costs. recent advances in assisted reproductive techniques (art) have made it possible to identify and overcome previously untreatable causes of male infertility. to properly utilize the available techniques and improve clinical results, it is of the utmost importance that patients are adequately diagnosed and evaluated. ideally, this initial assessment should also be affordable and accessible. we describe the main aspects of male infertility evaluation in a practical manner to provide information on the judicious use of available diagnostic tools and to better determine the etiology of the most adequate treatment for the existing condition.
Knowledge Level and Self-Reported Attitudes of Food Handlers: Case Study of a University Campus  [PDF]
Kamila Soares, Irene Oliveira, Alexandra Esteves, Maria C. Fontes, Cristina Saraiva
Health (Health) , 2016, DOI: 10.4236/health.2016.813139
Abstract: This study was performed conducting surveys to assess the Knowledge Level (KL) and Self-Reported Attitudes (SRA) of Food Handlers (FH) in order to evaluate their food safety perception. Food handlers working in 5 cafes and 6 canteens in a university campus responded to a questionnaire about food hygiene. The knowledge level about food hygiene was obtained by answering five question groups (G): Agents involved in food borne diseases (G1), Food handling hygiene (G2), Cross contamination (G3), Heat treatment/cooling techniques (G4), Reduced temperatures (G5). The SRA level was obtained through seven questions with multiple choice options on behaviors of health and safety applied to the work routine, which were considered as percentage of hits. The hygiene’s knowledge average was 75%, ranging from 63.3% (G4) to 94.5% (G3). Significant associations between establishment type and G1 (p = 0.027), professional experience and G5 (p = 0.020), training and G5 (p = 0.037) were found. Food handlers knowledge did not have effect in FH attitude (p = 0.371). From 25 FH (46.0%) who had high KL, 17 had reported incorrect attitudes. The level of hits is, in general, more than 75%, except for matters relating to the use of different cutting tables (44.4%) and knives (51.9%). Significant differences of values and odds for handlers’ knowledge were observed between cafes’ and canteens’ FH. No difference (p > 0.05) was observed in FH SRA scores according to the type of establishment. The results reveal a reduced application of knowledge acquired by food handlers, evidenced by the low level of attitudes considered correct. This clearly justifies the implementation of additional measures, including on job training as part of an effective strategy to control establishment’s food safety.
Energy expenditure: components and evaluation methods Gasto energético: componentes y métodos de evaluación
A. C. Pinheiro Volp,F. C. Esteves de Oliveira,R. Duarte Moreira Alves,E. A. Esteves
Nutrición Hospitalaria , 2011,
Abstract: Introduction: The determination of energy expenditure, considering the physical activity level and health status, is very important to adjust the individuals' nutritional supply. Energy expenditure can be determined by using indirect calorimetry, bioelectrical impedance, doubly labeled water, predictive equations, among others. All these methods have been used in clinical and research areas. However, considering the inconsistence in several research results, there is no consensus yet about the applicability of many of these methods. Objectives: The aim of this review is to describe the components of energy expenditure and the methods for its determination and estimation, summarizing their main advantages and limitations. Results and discussion: Indirect calorimetry and doubly labeled water are considered more accurate methods, but expensive. On the other hand, even though other methods present limitations, they are convenient and less expensive, and can be used with some caution. Introducción: Determinar el gasto energético (GE), considerando la actividad física y el estado de salud, es muy importante para ajustar el cálculo de la necesidad nutricional para cada individuo. Para eso, se pueden utilizar técnicas como la calorimetría indirecta, la bioimpedancia eléctrica, el agua doblemente marcada, las ecuaciones predictivas, entre otras. Estos métodos son utilizados en la práctica clínica y en estudios científicos. Sin embargo, debido a la inconsistencia de los resultados de estas investigaciones, todavía no hay un consenso respecto a su aplicabilidad. Objetivos: De esa forma, esta revisión tiene como objetivo discutir los componentes del gasto energético, así como las técnicas para su determinación y estimativa, se alando sus ventajas y limitaciones. Resultados y discusión: La calorimetría indirecta y el agua doblemente marcada son métodos considerados más acurados, sin embargo onerosos. Los otros métodos presentan limitaciones, pero por su practicidad y bajo coste, algunos de ellos pueden ser usados con cautela.
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