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Featured researches published by P.A. Navarro.


Human Reproduction | 2014

Follicular fluid from infertile women with mild endometriosis may compromise the meiotic spindles of bovine metaphase II oocytes

M.G. Da Broi; Helena Malvezzi; Claudia Cristina Paro de Paz; Rui Alberto Ferriani; P.A. Navarro

STUDY QUESTIONnWhat is the potential impact of follicular fluid (FF) from infertile women with mild endometriosis (ME) on oocyte quality, especially on nuclear maturation and the meiotic spindle?nnnSUMMARY ANSWERnFF from infertile women with ME may compromise nuclear maturation and the meiotic spindles of in vitro matured bovine oocytes.nnnWHAT IS KNOWN ALREADYnControversial studies have suggested that impaired oocyte quality may be involved in the pathogenesis of endometriosis-related infertility. Moreover, some studies have demonstrated alterations in the composition of FF from infertile women with endometriosis. However, to date no study has evaluated the effect of FF from infertile women with ME on the genesis of meiotic oocyte anomalies.nnnSTUDY DESIGN, SIZE, DURATIONnWe performed an experimental study. Samples of FF were obtained from February 2009 to February 2011 from 22 infertile women, 11 with ME and 11 with tubal or male factors of infertility (control group), who underwent ovarian stimulation for ICSI at our university IVF Unit. From March 2011 to February 2012 we performed in vitro maturation (IVM) experiments using immature bovine oocytes as described below.nnnPARTICIPANTS/MATERIALS, SETTING, METHODSnFF free of blood and containing a mature oocyte was obtained from 22 infertile women during oocyte retrieval for ICSI. Immature bovine oocytes underwent IVM in the absence of FF (No-FF) and in the presence of four concentrations (1, 5, 10 andxa015%) of FF from infertile women without endometriosis (C-FF) and with ME (ME-FF). Eleven replicates were performed, each one using FF from a control patient and a patient with ME. Each FF sample was used in only one experiment. After 22-24 h of IVM, oocytes were denuded, fixed and immunostained for morphological visualization of microtubules and chromatin by confocal microscopy.nnnMAIN RESULTS AND THE ROLE OF CHANCEnA total of 1324 cumulus-oocyte complexes were matured in vitro. Of these, 1128 were fixed and 1048 were analyzed by confocal microscopy. The percentage of meiotically normal oocytes was significantly higher for oocytes that underwent IVM in the absence of FF (No-FF; 76.5%) and in the presence of 1% (80.9%), 5% (76.6%), 10% (75%) and 15% (76.2%) C-FF than in oocytes that underwent IVM in the presence of 1% (44.4%), 5% (36.7%), 10% (45.5%) and 15% (51.2%) ME-FF (P < 0.01). No differences were observed among FF concentrations within each group. When the four concentrations from each group were pooled, the number of oocytes in metaphase I stage was significantly higher in the ME-FF (50 oocytes) than in the C-FF (29 oocytes) group and the percentage of meiotic abnormalities was significantly higher when oocytes were matured with ME-FF (55.8%) than with C-FF (23.1%), P < 0.01.nnnLIMITATIONS, REASONS FOR CAUTIONnOwing to the strict selection criteria for FF donors, this study had a small sample size (11 cases and 11 controls), and thus further investigations using a large cohort of patients are needed to confirm these results. In addition, data obtained from studies using animal models may not necessarily be extrapolated to humans and studies evaluating in vivo matured oocytes from infertile women with ME are important to confirm our results.nnnWIDER IMPLICATIONS OF THE FINDINGSnOur results open new insights into the pathogenic mechanisms of infertility related to mild endometriosis, suggesting that FF from infertile women with mild endometriosis may be involved in the worsening of oocyte quality of these women.nnnSTUDY FUNDING/COMPETING INTEREST(S)nThis study was supported by the National Council for Scientific and Technological Development (CNPq), Brazil. The authors declare no conflicts of interest.


Human Reproduction | 2015

Direct actions of androgens on the survival, growth and secretion of steroids and anti-Müllerian hormone by individual macaque follicles during three-dimensional culture

J.K. Rodrigues; P.A. Navarro; Mary B. Zelinski; Richard L. Stouffer; Jing Xu

STUDY QUESTIONnWhat are the direct effects of androgens on primate follicular development and function at specific stages of folliculogenesis?nnnSUMMARY ANSWERnAndrogen addition altered primate follicle survival, growth, steroid and anti-Müllerian hormone (AMH) production, and oocyte quality in vitro, in a dose- and stage-dependent manner.nnnWHAT IS KNOWN ALREADYnAndrogens have local actions in the ovary, particularly in the developing follicles. It is hypothesized that androgen promotes early follicular growth, but becomes detrimental to the antral follicles in primates.nnnSTUDY DESIGN, SIZE, DURATIONnIn vitro follicle maturation was performed using rhesus macaques. Secondary (125-225 µm) follicles were mechanically isolated from 14 pairs of ovaries, encapsulated into alginate (0.25% w/v), and cultured for 40 days.nnnPARTICIPANTS/MATERIALS, SETTING, METHODSnIndividual follicles were cultured in a 5% O2 environment, in alpha minimum essential medium supplemented with recombinant human FSH. Follicles were randomly assigned to experiments of steroid ablation by trilostane (TRL), testosterone (T) replacement and dihydrotestosterone (DHT) replacement. Follicle survival and growth were assessed. Follicles with diameters ≥500 μm at Week 5 were categorized as fast-grow follicles. Pregnenolone (P5), progesterone (P4), estradiol (E2) and AMH concentrations in media were measured. Meiotic maturation and fertilization of oocytes from recombinant human chorionic gonadotrophin-treated follicles were assessed at the end of culture.nnnMAIN RESULTS AND THE ROLE OF CHANCEnCompared with controls, TRL exposure reduced (P < 0.05) follicle survival, antrum formation rate and follicle diameters at Week 5. While P5 concentrations increased (P < 0.05) following TRL treatment, P4 levels decreased (P < 0.05) in fast-grow follicles at Week 5. Few healthy oocytes were retrieved from antral follicles developed in the presence of TRL. T replacement with TRL increased (P < 0.05) follicle survival and antrum formation at Week 5, compared with TRL alone, to levels comparable to controls. However, high-dose T with TRL decreased (P < 0.05) diameters of fast-grow follicles. Although P4 concentrations produced by fast-grow follicles were not altered by T in the presence of TRL, there was a dose-dependent increase (P < 0.05) in E2 levels at Week 5. High-dose T with TRL decreased (P < 0.05) AMH production by fast-grow follicles at Week 3. More healthy oocytes were retrieved from antral follicles developed in TRL+T compared with TRL alone. DHT had the similar effects to those of high-dose T, except that DHT replacement decreased (P < 0.05) E2 concentrations produced by fast-grow follicles at Week 5 regardless of TRL treatment.nnnLIMITATION, REASONS FOR CAUTIONnThis study reports T and DHT actions on in vitro-developed individual primate (macaque) follicles, which are limited to the interval from the secondary to small antral stage.nnnWIDER IMPLICATION OF THE FINDINGSnThe above findings provide novel information on the role(s) of androgens in primate follicular development and oocyte maturation. We hypothesize that androgens promote pre-antral follicle development, but inhibit antral follicle growth and function in primates. While androgens can act positively, excess levels of androgens may have negative impacts on primate folliculogenesis.nnnSTUDY FUNDING/COMPETING INTERESTSnNIH U54 RR024347/RL1HD058294/PL1EB008542 (Oncofertility Consortium), NIH U54 HD071836 (SCCPIR), NIH ORWH/NICHD 2K12HD043488 (BIRCWH), NIH FIC TW/HD-00668, ONPRC 8P51OD011092. There are no conflicts of interest.


Revista Brasileira de Ginecologia e Obstetrícia | 2010

Serum markers of oxidative stress and assisted reproduction procedures results in infertile patients with polycystic ovary syndrome and controls

J.K. Rodrigues; L.A. Dib; Rui Alberto Ferriani; Alceu Afonso Jordão Júnior; P.A. Navarro

PURPOSEnTo compare the serum levels of five markers of oxidative stress and assisted reproduction (AR) outcomes among infertile patients, with tubal and/or male factor and with polycystic ovary syndrome (PCOS).nnnMETHODSn70 patients were included, 58 with tubal and/or male factor infertility and 12 with PCOS, who underwent controlled ovarian stimulation to perform intracytoplasmic sperm injection (ICSI). A blood sample was collected between the third and fifth day of the menstrual cycle in the month prior to ovarian stimulation. We analyzed the levels of malondialdehyde, hydroperoxides, protein oxidation products, glutathione and vitamin E, by reading the absorbance with a spectrophotometer and by high performance liquid chromatography (HPLC). Data were analyzed statistically by the Students t-test and Fishers exact test.nnnRESULTSnSignificant increases in the body mass index, ovarian volume and number of antral follicles were observed in PCOS patients, as well as the use of a lower total dose of follicle stimulating hormone for these patients. There were no differences in the response to ovarian stimulation, in the results of AR or serum levels of malondialdehyde, hydroperoxides, advanced oxidation protein products, glutathione and vitamin E between groups.nnnCONCLUSIONSnThe present data did not demonstrate a difference in the levels of serum markers of oxidative stress or in AR results when comparing non-obese infertile patients with PCOS and controls. These data suggest that the results of AR may not be compromised in this specific subgroup of patients with PCOS. However, interpretations of the action of oxidative stress on the results of AR are still not clear and the reproductive implications of oxidative stress need to be better evaluated.


Revista Brasileira de Ginecologia e Obstetrícia | 2012

Oócitos aparentemente maduros injetados em telófase I apresentam piores resultados de reprodução assistida

L.A. Dib; Maria Cristina Picinato Medeiros de Araújo; Roberta Cristina Giorgenon; Rui Alberto Ferriani; P.A. Navarro

PURPOSE: To evaluate the nuclear maturation stage and the presence of meiotic spindles of in vivo matured oocytes from infertile women undergoing stimulated cycles for intracytoplasmic sperm injection (ICSI) and compare intracytoplasmic sperm injection outcomes between oocytes in telophase I (TI) and metaphase II (MII), and the ones with and without visible meiotic spindle. METHODS: A prospective and controlled study with 106 infertile patients who underwent ovarian stimulation for intracytoplasmic sperm injection purposes. Patients aged 38 years or less, with basal follicle stimulating hormone (FSH) less than 10 mIU/mL and body mass index (BMI) less than 30 kg/m². Were included patients presenting any systemic diseases, any active infection, smokers or patients who had been using hormonal medications and hormonal and nonhormonal anti-inflammatory drugs for the past two months prior to the assisted reproduction procedure were excluded. The oocytes with the first polar body extruded (in vivo matured oocytes) were imaged by polarization microscopy immediately before intracytoplasmic sperm injection and characterized according to nuclear maturation stage (telophase I and metaphase II) and to the presence of a meiotic spindle. We analyzed the fertilization rates, cleavage, number of good quality embryos on the second day (D2) from oocytes on telophase I versus those in metaphase II, and metaphase II visible spindle versus non-visible ones. Data were analyzed comparatively by Fishers exact test. The level of significance was set at 5% in all analyses (p<0.05). RESULTS: The meiotic spindles of 516 oocytes were imaged using polarization microscopy. From the 516 oocytes analyzed, seventeen were in telophase I (3.3%) and 499 (96.7%) in metaphase II. The oocytes injected in telophase I had significantly lower fertilization rates than those injected in metaphase II (53 and 78%, respectively) and produced no good quality embryos on day 2. When the oocytes with and without a visible meiotic spindle were compared, there was no significant difference in the intracytoplasmic sperm injection results. CONCLUSIONS: Oocytes injected in telophase I showed lower fertilization rates when compared to those in metaphase II. It is possible that the analysis of oocyte nuclear maturation by polarization microscopy can be used as a predictor of fertilization after intracytoplasmic sperm injection.


Journal of Assisted Reproduction and Genetics | 2018

Influence of follicular fluid and cumulus cells on oocyte quality: clinical implications

M.G. Da Broi; Vanessa Silvestre Innocenti Giorgi; Fang Wang; David L. Keefe; D. Albertini; P.A. Navarro

An equilibrium needs to be established by the cellular and acellular components of the ovarian follicle if developmental competence is to be acquired by the oocyte. Both cumulus cells (CCs) and follicular fluid (FF) are critical determinants for oocyte quality. Understanding how CCs and FF influence oocyte quality in the presence of deleterious systemic or pelvic conditions may impact clinical decisions in the course of managing infertility. Given that the functional integrities of FF and CCs are susceptible to concurrent pathological conditions, it is important to understand how pathophysiological factors influence natural fertility and the outcomes of pregnancy arising from the use of assisted reproduction technologies (ARTs). Accordingly, this review discusses the roles of CCs and FF in ensuring oocyte competence and present new insights on pathological conditions that may interfere with oocyte quality by altering the intrafollicular environment.


JBRA assisted reproduction | 2017

Expression of PGR, HBEGF, ITGAV, ITGB3 and SPP1 genes in eutopic endometrium of infertile women with endometriosis during the implantation window: A pilot study

M. G. Da Broi; C. V. Rocha Junior; Juliana Meola; Wellington P. Martins; Filomena Marino Carvalho; Rui Alberto Ferriani; P.A. Navarro

OBJECTIVEnAlterations in endometrial receptivity may be involved in the etiopathogenesis of endometriosis-related infertility. The literature has suggested that patients with endometriosis present progestin resistance, which could affect embryo implantation. We question the presence of alterations in the expression of the progesterone receptor gene (PGR) and the genes related to endometrium-embryo interaction regulated by progesterone. This pilot study compared the expression of PGR, HBEGF, ITGAV, ITGB3, and SPP1 genes in eutopic endometrium during the implantation window (IW) in infertile women with endometriosis with that observed in the endometrium of fertile and infertile controls.nnnMETHODSnIn this prospective case-control study, endometrial biopsies were performed during the IW in patients aged between 18 and 45 years old, with regular cycles and without endocrine/systemic dysfunctions, divided into endometriosis (END), infertile control (IC) and fertile control (FC) groups. Total RNA extraction, cDNA synthesis, and gene expression analysis by Real-Time PCR were performed. We assessed the size of the difference that our series was powered to detect.nnnRESULTSnFrom the 687 patients who underwent diagnostic videolaparoscopy or tubal ligation at the University Hospital, 130 were eligible. Of these, 32 had endometrial samples collected, with 17 confirmed in the IW. Fifteen samples (5 END, 5 IC and 5 FC) were analyzed. There was no significant difference in the expression of any studied gene. Our sample size allowed us to identify or discard large differences (two standard deviations) among the groups.nnnCONCLUSIONnEndometriosis doesnt cause large changes in the endometrial expression of PGR, HBEGF, ITGAV, ITGB3 and SPP1 during the IW.


Journal of Andrology | 2017

Magnetic-activated cell sorting before density gradient centrifugation improves recovery of high-quality spermatozoa

T. S. Berteli; M.G. Da Broi; Wellington P. Martins; Rui Alberto Ferriani; P.A. Navarro

Recent studies have evaluated the use of magnetic‐activated cell sorting (MACS) to reduce apoptotic spermatozoa and improve sperm quality. However, the efficiency of using MACS alone, before or after sperm processing by density gradient centrifugation (DGC) has not yet been established. The purpose of this study is to determine the optimal protocol of MACS in assisted reproduction techniques (ART). Thus, we compared sperm quality obtained by DGC alone (DGC), DGC followed by MACS (DGC‐MACS), MACS followed by DGC (MACS‐DGC), and MACS alone (MACS), and found that the combined methods (MACS‐DGC and DGC‐MACS) led to retrieval of less spermatozoa with fragmented DNA compared to the single protocols. However, MACS‐DGC protocol led to a significantly higher percentage of spermatozoa with progressive motility and normal morphology than DGC‐MACS protocol. These findings suggest the potential clinical value of using MACS‐DGC to improve sperm quality in seminal preparation for ART.


Revista Brasileira de Ginecologia e Obstetrícia | 2012

Análise invasiva e não invasiva do fuso meiótico de oócitos humanos obtidos de ciclos estimulados: dados preliminares

L.A. Dib; Michele Gomes Da Broi; Maria Cristina Picinato Medeiros de Araújo; Roberta Cristina Giorgenon; Rui Alberto Ferriani; P.A. Navarro

PURPOSE: To evaluate the concordance between polarization microscopy and confocal microscopy techniques in the evaluation of the meiotic spindle of human oocytes matured in vivo. METHODS: Prospective study that evaluated oocytes with the first polar extruded body obtained from infertile women who had undergone ovarian stimulation for intracytoplasmic sperm injection. The oocytes with the first polar extruded body were evaluated by polarization microscopy and were then immediately fixed and stained for microtubule and chromatin evaluation by high-performance confocal microscopy. We determined the correlation of polarization microscopy with confocal microscopy in the detection of meiotic oocyte anomalies, and we also evaluated the percentage of oocytes with a visible and non-visible cell spindle by polarization microscopy and with meiotic normality and abnormalities by confocal microscopy. Confidence intervals, Kappas index and concordance between the methodologies were calculated, considering immunofluorescence microscopy analysis as the golden-standard for evaluating normal spindle and oocyte chromosome distribution. RESULTS: We observed that 72.7% of metaphase II oocytes with a nonvisible meiotic spindle by polarization microscopy showed no meiotic abnormalities by confocal analysis and 55.6% of metaphase II oocytes with a visible meiotic spindle by polarization microscopy were found to be abnormal oocytes by the confocal analysis. Only 44.4% of oocytes with a visible meiotic spindle by polarization microscopy were found to be normal by confocal analysis. Concordance between the methods was 51.1% (Kappa: 0.11; 95%CI -0.0958 - 0.319). CONCLUSIONS: The low correlation between polarization microscopy and confocal microscopy in the assessment of oocyte meiotic spindle suggests that visualization of the meiotic spindle of human oocytes at metaphase II by polarization microscopy is not a good indicator of oocyte meiotic normality.


Fertility and Sterility | 2010

Influence of pituitary suppression and controlled ovarian hyperstimulation (COH) on oxidative stress markers of infertile patients with endometriosis and controls

F.C. Donabela; A.Z. Andrade; J.K. Rodrigues; L.A. Dib; Alceu Afonso Jordão; P.A. Navarro

INFLUENCE OF PITUITARY SUPPRESSION AND CONTROLLED OVARIAN HYPERSTIMULATION (COH) ON OXIDATIVE STRESS MARKERS OF INFERTILE PATIENTS WITH ENDOMETRIOSIS AND CONTROLS. F. C. Donabela, A. Z. Andrade, J. K. Rodrigues, L. A. Dib, A. A. Jord~ao, Jr, P. A. Navarro. Dept. of Ob/Gyn, Faculty of Medicine of Ribeir~ao Preto, University of S~ao Paulo, Ribeir~ao Preto, SP, Brazil; National Institute of Hormones and Woman’s Health, CNPq, Ribeir~ao Preto, SP, Brazil; Nutrition and Metabolism Laboratory, Faculty of Medicine of Ribeir~ao Preto, University of Sao Paulo, Ribeir~ao Preto, SP, Brazil.


Fertility and Sterility | 2010

Serum markers of oxidative stress in infertile women with endometriosis and controls

F.C. Donabela; A.Z. Andrade; J.K. Rodrigues; L.A. Dib; Alceu Afonso Jordão; P.A. Navarro

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Rui Alberto Ferriani

National Institute of Standards and Technology

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M.G. Da Broi

University of São Paulo

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L.A. Dib

University of São Paulo

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J.K. Rodrigues

University of São Paulo

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Juliana Meola

University of São Paulo

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Rui Alberto Ferriani

National Institute of Standards and Technology

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A.Z. Andrade

University of São Paulo

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