55 research outputs found
On Bobkov-Tanaka type spectrum for the double-phase operator
No full textMoving from the seminal papers by Bobkov and Tanaka \cite{BT,BT2,BT3} on the spectrum of the -Laplacian, we analyze the case of the double-phase operator. We discuss the region of parameters in which existence and non-existence of positive solutions occur. The proofs are based on normalization procedures, the Nehari manifold, and truncation techniques, exploiting Picone-type inequalities and an ad-hoc strong maximum principle
Fractional Dirichlet problems with singular and non-locally convective reaction
No full textIn this paper, the existence of positive weak solutions to a Dirichlet
problem driven by the fractional -Laplacian and with reaction both
weakly singular and non-locally convective (i.e., depending on the
distributional Riesz gradient of solutions) is established. Due to the nature
of the right-hand side, we address the problem via sub-super solution methods,
combined with variational techniques, truncation arguments, as well as fixed
point results
"Metodiche di valutazione del liquido seminale nella diagnosi dell'infertilità di coppia."
No full textA quick molecular method for the simultaneous detection in spermatozoa of nuclear, acrosomal and axonemal structure by fluorescent microscopy
No full textEjaculated spermatozoa from infertile men presenting to our laboratory for semen analysis were processed with a new molecular method which reveals simultaneously, in the same sperm cell, the status of the acrosome, by testing the hyaluronidase content, the texture of the nucleus, by checking the DNA strands breaks, and the structure of the axoneme, revealing the tubulin content. The presence of hyaluronidase and tubulin is essential for the sperm function, and the analysis of the DNA status reveals the eventual apoptotic process. Using this method in normal spermatozoa, the staining of the acrosomal hyaluronidase reveals, by yellow-green fluorescence, the shape of the acrosomal complex and its texture. At the same time, in the same sperm cell, the staining of the axonemal tubulin demonstrates, by a red labeling, the presence of the protein and therefore the consistence of the axonemal structure. Simultaneously, at the head level, the absence of red labeling from nuclear DNA indicates that the apoptotic process is not present. This protocol allows quantification of the frequency of the presence of normal or abnormal spermatozoa, by an easy scoring and calculation of the apoptotic sperm or of the sperm with generic defects at acrosomal or flagellar level. The percentage of normal spermatozoa evaluated by the triple staining method has been compared with the results of the PAP staining and of the ultrastructural analysis, statistically elaborated. Triple staining results more severe than the PAP method, but TEM analysis is the finest technique to detect sperm abnormality because it considers the entire panel of sperm defects.
Human spermatozoa; Immunofluorescence; Triple staining; TUNE
The impact of environmental exposure to perfluorinated compounds on oocyte fertilization capacity
No full textIn an attempt to assess the effect of perfluorinated compounds (PFC) on oocytes quality and fertilization rate, we studied follicular fluid (FF) PFC levels in 18 patients undergoing IVF-ET cycles. A significant correlation (R∈=∈0.75; P∈<∈0.001) was observed between FF PFC levels and fertilization rate. Moreover, patients with FF PFC contamination had significantly lower fertilization rate (p∈<∈0.02) and number of embryos transferred (p∈<∈0.02), compared to the PFC negative group. © 2011 Springer Science+Business Media, LLC
Successful multiple pregnancy achieved after transfer of frozen embryos obtained via intracytoplasmic sperm injection with testicular sperm from an AZFc-deleted man
No full textObjective: To describe a case of successful triplet pregnancy after testicular sperm extraction (TESE) from a man with AZFc deletion and intracytoplasmic sperm injection (ICSI). Design: Case report. Setting: University hospital. Patient(s): A 38-year-old man affected by complete AZFc deletion and azoospermia. Intervention(s): Spermiogram, Y-chromosome microdeletion screening, TESE for sperm recovery from testicular tissue on the same day as ICSI, transfer of frozen-thawed embryos, vaginal ultrasound examination. Main Outcome Measure(s): The Y chromosome genetic status of an azoospermic patient who underwent TESE and ICSI, the fertilization and pregnancy outcome. Result(s): The patient was found to be azoospermic, and the deletion screening showed complete AZFc deletion. After TESE, the recovered testicular sperm were selected for ICSI. Three good quality embryos were obtained and were frozen due to ovarian hyperstimulation syndrome in the female partner. After transfer of the thawed embryos, a triplet pregnancy was diagnosed by vaginal ultrasonography at the seventh week of gestation. Two male and one female healthy babies were born. Conclusion(s): This is the first report of a successful triplet pregnancy after the transfer of frozen-thawed embryos in a couple in whom the male partner was azoospermic and a carrier of complete AZFc deletion. This deletion should not adversely affect a man's TESE retrieval prognosis or the fertilization, cleavage, and implantation of embryos. The offspring were healthy, although the two sons inherited the AZFc deletion. Copyright © 2010 American Society for Reproductive Medicine, Published by Elsevier Inc
Seminal F2-IsoP and RvD1 Levels in Idiopathic Infertile Men
No full text30 percent of infertile men are diagnosed with idiopathic infertility. This study aimed to assess oxidative stress in the semen of 77 patients with idiopathic infertility by measuring F2-isoprostane (F2-IsoP), resolvin D1 (RvD1) levels, and semen parameters. The presence and localization of 8-IsoProstaglandin F2α were determined using immunofluorescence. No significant correlations were observed for F2-IsoP and RvD1 levels with the semen variables. Based on F2-IsoP levels, individuals were classified into two groups: Group 1 (F2-IsoPs ≤ 29.96 ng/mL, 51%) and Group 2 (F2-IsoPs > 29.96 ng/mL, 49%). In comparison to Group 1, Group 2 showed significantly higher F2-IsoP levels (13.33 ng/mL vs. 44.80 ng/mL; p < 0.05), a lower progressive motility percentage (30% vs. 25%; p < 0.05), and increased RvD1 levels (36.09% vs. 44.94%). Immunofluorescence analysis revealed a different localization of 8-IsoProstaglandin F2α in the ejaculated sperm of Group 1 compared to that observed in Group 2. A weak signal was detected in the sperm tail (Group 1, 79.1% vs. Group 2, 36.9; p < 0.01). In spermatozoa of Group 2 patients, a strong signal in the acrosome, midpiece, and tail was highlighted. These findings suggest the need to test oxidative stress during routine semen analysis in patients with idiopathic infertility to improve diagnosis and treatment
Chromosomal Aberrations and aneuploidies of Spermatozoa
No full textChromosomal abnormalities are relevant causes of human infertility, affecting 2 -14 % of infertile males. Patients with seminal anomalies could be affected by improper meiotic recombination and increased sperm chromosome aneuploidy. Since the transmission of a haploid chromosomal asset is fundamental for embryo vitality and development, the study of sperm chromosomes has become fundamental because intracytoplasmic sperm injection allows fertilization in cases of severe male infertility. In this chapter we summarize the data on the incidence of sperm aneuploidy, detected by fluorescence in situ hybridization (FISH), in infertile men with normal or abnormal karyotype. The possibility of reducing sperm chromosomal imbalance is also reported. Among control males, the lowest aneuploidy rate was detected (range: 0.09 -0.14 % for autosomes; 0.04 -0.10 % for gonosomes). In infertile patients with normal karyotype, the severity of semen alteration is correlated with the frequency of aneuploidy, particularly for X and Y chromosomes. Among patients with abnormal karyotype, 47,XXY and 47,XYY carriers showed a high variability of sperm aneuploidy both for gonosomes and autosomes. In Robertsonian translocation carriers, the increase in aneuploidy rate was particularly evident for total sex disomy, and resulted mainly from interchromosomal effect (ICE). In reciprocal translocation carriers, a high percentage of unbalanced sperm (approximately 50 %) was detected, perhaps mostly related to ICE. Sperm chromosomal constitution could be analyzed to obtain more accurate information about the causes of male infertility. It would be worthwhile to evaluate the benefits of a therapy with recombinant Follicle Stimulating Hormone (rFSH) on sperm chromosome segregation in selected infertile males. © 2014 Springer Science+Business Media New York
10, 15 reciprocal translocation in an infertile man: ultrastructural and fluorescence in-situ hybridization sperm study: Case report
No full textBackground: Peculiar sperm defects are described in a sterile man heterozygous for a balanced translocation t(10;15) (q26;q12). As this structural reorganization was absent in the parents, the translocation must have appeared de novo in the present patient. Methods: Spermatozoa were analysed under light and transmission electron microscopy (TEM). Fluorescence in-situ hybridization (FISH) was performed on the lymphocyte karyotype. Aneuploidy frequencies of chromosomes 18, X and Y in sperm nuclei, not involved in the translocation, were investigated using three-colour FISH. Dual-colour FISH was used to evaluate segregation of chromosomes 10, 15 in decondensed sperm nuclei. Moreover, three-colour FISH, using telomeric probes for chromosomes 10, 15 was performed in order to distinguish balanced and unbalanced gametes. Results and conclusions: Overall, structural characteristics indicate general immaturity of the germinal cells. FISH sperm analysis detected an increase in chromosome 18 disomy (0.81%) suggesting an interchromosomal effect. A high frequency of diploidies, particularly 18,18,X,X and 18,18,X,Y, was also found. FISH segregation analysis for chromosomes 10, 15 indicated that 32.8% were balanced gametes, whereas 68.2% were unbalanced. Taken together, these data demonstrate in a male carrier of a reciprocal translocation t(10;15) the presence of diffuse ultrastructural sperm alterations and a high frequency of sperm aneuploidies. The existence of a correlation among these factors is proposed
Protein modification as oxidative stress marker in normal and pathological human seminal plasma
No full textObjective: Our study aims to assess the oxidative stress status of seminal plasma from normozoospermic, azoospermic, and leukocytospermic males, since abnormal sperm and leukocytes in human ejaculates are the main source of reactive oxygen species (ROS) which lead to oxidative damages. For this purpose we applied a biochemical approach to the assessment of the oxidative stress status by using twodimensional (2D) electrophoresis to check the level of protein oxidation after specific labeling of free thiol (-SH) groups. Methods: Seminal plasma samples from normal and pathological males were analyzed by a luminol-based chemiluminescent assay. The same samples after specific labeling of free -SH groups with 3-Nmaleimidopropionyl biocytin, were analyzed by 2D electrophoresis and computer-assisted semiquantitative determination of the amount of free -SH groups. Results: Using a standard chemiluminescence assay, we demonstrated a high, low and normal level of ROS, respectively, in seminal plasma from leukocytospermic, azoospermic, and normozoospermic subjects. By 2D electrophoresis and streptavidin blotting of specifically labeled free -SH groups of proteins, we detected in the same samples a higher level of oxidated -SH groups comparable between azoospermic and leukocytospermic samples, whereas a significantly higher level of free -SH groups was detected in normozoospermic subjects. Discussion: Our results demonstrated that a pathological oxidative stress status in seminal plasma may be revealed by the levels of the protein free -SH groups, both in the presence or absence of cells. © W.S. Maney & Son Ltd 2012
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