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Biomedical subjects

A Ferlin

Publications and source records attributed to A Ferlin.

At least 55 records · Page 3Linked to original sources
PubMed1999

Sperm treatment with extracellular ATP increases fertilization rates in in-vitro fertilization for male factor infertility.

Previous work from our laboratory has revealed that extracellular ATP is a rapid and potent activator of human sperm acrosome reaction and fertilizing ability. In the present study, we assessed the effects of in-vitro sperm incubation with ATP on fertilization and embryo development in couples undergoing in-vitro fertilization (IVF) for male factor infertility. Oocytes from 22 women undergoing ovulation induction were divided in two groups and inseminated in vitro either with selected spermatozoa from the corresponding partner suffering from male factor infertility pre-incubated with ATP (2.5 mM) for 1 h, or with spermatozoa incubated with 0.9% NaCl solution (control group). After insemination, fertilization was assessed by the presence of pronuclei and then by embryo cleavage. The fertilization rate in the group of oocytes inseminated with ATP-treated spermatozoa improved significantly with respect to the control group (65.7 versus 42.5%, P < 0.01). No significant differences were observed in embryo cleavage and embryo quality. Embryos from both treated and control groups were transferred together in 20 transfer procedures, and in two couples fertilization was not obtained. Nine pregnancies occurred: one biochemical, one miscarriage, and seven patients delivered 9 healthy babies. Two pregnancies were twin with an overall pregnancy rate of 40.9% per cycle and of 45% per transfer. In conclusion, the results of the present study demonstrate that, in humans, extracellular ATP induces a significant increase of sperm fertilizing potential, as these findings are a rationale for the use of ATP for in-vitro treatment of human spermatozoa during IVF.

Adenosine Triphosphate↗
PubMed1999

Human male infertility and Y chromosome deletions: role of the AZF-candidate genes DAZ, RBM and DFFRY.

Microdeletions in Yq11 overlapping three distinct 'azoospermia factors' (AZFa-c) represent the aetiological factor of 10-15% of idiopathic azoospermia and severe oligozoospermia, with higher prevalence in more severe testiculopathies, such as Sertoli cell-only syndrome. Using a PCR-based screening, we analysed Yq microdeletions in 180 infertile patients affected by idiopathic Sertoli cell-only syndrome and different degrees of hypospermatogenesis, compared with 50 patients with known causes of testicular alteration, 30 with obstructive azoospermia, and 100 normal fertile men. In idiopathic severe testiculopathies (Sertoli cell-only syndrome and severe hypospermatogenesis), a high prevalence of microdeletions (34.5% and 24.7% respectively) was found, while milder forms were not associated with Yq alteration. No deletions were found in testiculopathies of known aetiology, obstructive azoospermia, normal fertile men and male relatives of patients with deletions. Deletions in the AZFc region involving the DAZ gene were the most frequent finding and they were more often observed in severe hypospermatogenesis than in Sertoli cell-only syndrome, suggesting that deletions of this region are not sufficient to cause complete loss of the spermatogenic line. Deletions in AZFb involving the RBM gene were less frequently detected and there was no correlation with testicular phenotype, with an apparent minor role for such gene in spermatogenesis. The DFFRY gene was absent in a fraction of patients, making it a candidate AZFa gene. Our data suggest that larger deletions involving more than one AZF-candidate gene are associated with a more severe testicular phenotype.

Chromosome Deletion↗
PubMed1999

Absence of testicular DAZ gene expression in idiopathic severe testiculopathies.

Deletions of the DAZ (deleted in azoospermia) gene family are frequently responsible for male infertility and are generally assessed by analyses of genomic DNA extracted from peripheral leukocytes. The multicopy nature of this gene prevents the distinction of intragenic deletions or deletions not involving the whole DAZ gene cluster. Thus it is still unclear whether each DAZ copy is effectively expressed in the testis. We analysed, by reverse transcription-polymerase chain reaction (RT-PCR), the expression of DAZ, RBM and SRY genes, in testicular cells from infertile men affected by idiopathic severe hypospermatogenesis, obstructive azoospermia and Sertoli cell-only syndrome. Normal mRNA for DAZ, RBM and SRY were observed in obstructive azoospermia, whereas only SRY transcripts were detected when only Sertoli cells were present. Nine out of 10 patients affected by idiopathic severe hypospermatogenesis had normal expression of SRY, RBM and DAZ, while in one patient no DAZ transcript was detected, suggesting that his testiculopathy was related to the absence of DAZ expression. The lack of DAZ mRNA in testicular cells with an apparently normal DAZ gene constitution on DNA extracted from leukocytes may be explained by different hypotheses: (i) not all the copies of the DAZ gene cluster are transcribed in the germ cells and the reported patient had a small deletion involving only the active ones; (ii) the patient may be mosaic for the DAZ gene having a normal constitution in leukocytes and be deleted for DAZ gene in the testis; (iii) abnormalities of DAZ transcription may exist. These findings highlight the intrinsic interpretative difficulties of normal PCR analysis for DAZ and RBM on leukocytes and suggest caution in the use of germ cells for assisted reproductive techniques in these cases to avoid transmission of genetic abnormalities to male offspring.

Biopsy, Needle↗
PubMed1999

Analysis of meiosis in intratesticular germ cells from subjects affected by classic Klinefelter's syndrome.

Azoospermic subjects affected by Klinefelter's syndrome may occasionally show the presence of intratesticular residual foci of spermatogenesis, and the retrieval of mature spermatozoa from the testis may permit fertility and paternity by means of intracytoplasmic sperm injection. Previous studies have demonstrated that these subjects show the presence of an increased incidence of hyperaploid spermatozoa. Here we analyzed, by fluorescence in situ hybridization using specific probes for chromosomes 8, X, and Y, the spermatogenic process and the meiotic progression of 47,XXY germ cells retrieved by fine needle aspiration of the testis in ten azoospermic patients affected by classic Klinefelter's syndrome. All patients had lower testicular volume, higher gonadotropins, and lower testosterone plasma levels compared with control subjects. Cytological analysis of the testicular cells retrieved by fine needle aspiration showed the presence of Sertoli cells only in eight subjects, while germ cells were observed in two patients. In each patient Sertoli cells showed a 47,XXY karyotype, and the same chromosome pattern was observed in spermatogonia and primary spermatocytes of patients presenting a residual spermatogenesis. Secondary spermatocytes, spermatids, and mature spermatozoa showed different sex chromosome patterns, reflecting their origin from 47,XXY spermatogonia. In conclusion, this study demonstrated that, in subjects affected by Klinefelter's syndrome, residual germ cells may be present in the testis and that 47,XXY spermatogonia are able to undergo and complete the spermatogenic process leading to mature spermatozoa. These data further suggest the need to evaluate the sex chromosome status of sperm from patients affected by Klinefelter's syndrome undergoing assisted reproductive techniques.

Adult↗
PubMed1999

Y chromosome microdeletions in cryptorchidism and idiopathic infertility.

To clarify whether cryptorchidism might be the expression of an intrinsic congenital testicular abnormality, we investigated the frequency of Y chromosome long arm (Yq) microdeletions in unilateral excryptorchid subjects manifesting an important bilateral testiculopathy. Microdeletion analysis of Yq was performed by polymerase chain reaction in the following subjects: 40 unilateral excryptorchid patients with azoospermia or severe oligozoospermia due to a bilateral severe testiculopathy (Sertoli cell-only syndrome or severe hypospermatogenesis); 20 unilateral excryptorchid men with moderate oligozoospermia and a normal testicular cytological picture in the contralateral testis; 110 patients affected by idiopathic severe primary testiculopathies; 20 patients affected by idiopathic moderate testiculopathy; and, as controls, 50 patients affected by known causes of testiculopathy and 100 fertile men. Eleven of 40 (27.5%) unilateral excryptorchid patients affected by bilateral testiculopathy and 28 of 110 (25.4%) patients affected by idiopathic severe primary testiculopathy showed Yq microdeletions, whereas no microdeletions were found in all the other subjects, nor in male relatives of patients with deletions. Microdeletions were located in different parts of Yq, including known regions involved in spermatogenesis (DAZ and RBM, AZFa, b, and c) and other loci still poorly defined. No difference in localization of deletions was evident between cryptorchid and idiopathic patients. Microdeletions in Yq may be responsible for severe bilateral testicular damage that could be phenotypically expressed by unilateral cryptorchidism, as well as by idiopathic infertility.

Adult↗
PubMed1998

Evidence for a stimulatory role of follicle-stimulating hormone on the spermatogonial population in adult males.

OBJECTIVE: To evaluate the effects of treatment with FSH on seminal indices and on the seminiferous epithelium of oligozoospermic subjects with normal FSH plasma levels. DESIGN: Placebo-controlled, double-blind randomized study. SETTING: Academic setting. PATIENT(S): Ninety subjects with idiopathic oligozoospermia (sperm count of < 10 x 10(6)/mL) and normal plasma levels of FSH. INTERVENTION(S): Three months of treatment with FSH (60 patients) or placebo (30 patients); bilateral testicular fine-needle aspiration. MAIN OUTCOME MEASURE(S): Seminal indices; testicular cytologic features; plasma levels of FSH, LH, and testosterone; and ultrasonographic testicular examination. RESULT(S): According to seminal indices, patients treated with FSH and placebo were classified as nonresponders or as responders (as determined by at least a doubling of sperm count). No placebo-treated patients responded to treatment. Among FSH-treated patients, 20 responded to hormonal treatment and 40 did not. The results of pretreatment cytologic examination of testicular specimens from patients who did not respond to FSH treatment were consistent with hypospermatogenesis associated with maturational disturbances at the spermatid level. In contrast, patients who responded to treatment with FSH had isolated hypospermatogenesis without maturational disturbances. After FSH therapy, we detected an increase of spermatogonia and spermatocyte population in both the responder and nonresponder subjects. This increase was associated with an activation of spermatogenic and spermiogenic processes and with a rise in ejaculated sperm concentration only when isolated hypospermatogenesis was present (responder patients). CONCLUSION(S): The findings of this study demonstrate that FSH treatment increases the spermatogonial population in men. This treatment may be appropriate for oligozoospermic subjects who have normal FSH plasma levels and a testicular evaluation characterized by hypospermatogenesis without maturational disturbances.

Adult↗
PubMed1998

Doppler ultrasound of the testis in azoospermic subjects as a parameter of testicular function.

Azoospermia frequently represents the end-point of different pathological conditions that cause important quantitative and qualitative alterations of both spermatogenesis and testicular structure, including intratesticular blood vessels. In this study we performed colour Doppler ultrasound of the testis in 12 azoospermic subjects affected by primary testicular pathology (four bilateral post-orchitis, four postradiotheraphy for cancer, four post-traumatic) aged 28.2+/-3.3 (mean+/-SD) years, in six subjects affected by obstructive azoospermia aged 29.7+/-2.4 years and in 20 age-matched fertile subjects (aged 28.6+/-2.5 years). The analysis of intratesticular vessels per organ was quantified using a semiquantitative score: category 0, no vessels visible; category 1, between one and three intratesticular vessels visible; and category 2, more than three vessels visible. In obstructive azoospermic patients and in fertile subjects there were always more than three intratesticular vessels. No intratesticular vessels were detected in eight testes (33.3%) and fewer than three vessels in 16 testes (66.6%) in subjects affected by primary testicular pathology. In azoospermic subjects the testicular structure of the testis was evaluated by diagnostic fine needle aspiration cytology (FNAC) performed in the middle portion of the testis. In non-obstructive azoospermic patients this procedure showed the presence of only Sertoli cells in all cases. When detectable vessels were present, a new aspiration was performed in these areas. In 12 out of 16 cases, spermatogenetic cells including mature spermatozoa, were found when the FNAC was performed in testicular regions showing the presence of blood vessels. These results indicate that colour Doppler sonography of the testis may be useful in the differential diagnosis of azoospermia and suggest the evaluation of the intratesticular blood vessel distribution before performing any method to retrieve intratesticular spermatozoa for intracytoplasmic sperm injection.

Adult↗
PubMed1998

High frequency of well-defined Y-chromosome deletions in idiopathic Sertoli cell-only syndrome.

Idiopathic Sertoli cell-only syndrome (SCOS) is characterized by azoospermia, small testes, absence of germ cells in the testes, elevated follicle stimulating hormone and normal testosterone concentrations. The Y-chromosome is involved in the regulation of spermatogenesis and in the pathogenesis of a fraction of idiopathic male infertility. An azoospermia factor (AZF) is present on the Y-chromosome long arm euchromatic region (Yq11) and two gene families (DAZ and RBM) have been identified within this region. The aim of this study was to investigate whether a specific pattern of Yq11 microdeletions may be associated with idiopathic SCOS. Eighteen idiopathic subjects showing a testicular cytological picture of bilateral SCOS were selected and tested by polymerase chain reaction for a set of 29 Y-specific sequence-tagged sites (STS). We found Yq microdeletions in 10 out of 18 patients (55.5%) while the fathers or brothers of six out of 10 patients deleted for Yq were shown to carry an intact Y-chromosome. These deletions may therefore be considered as de-novo deletions and the cause of SCOS. The analysis of the microdeletions allowed us to identify two homogeneous regions that have a high incidence of deletion. The smallest deletion, common to all patients, is located in Yq interval 5. We therefore speculate that there is a relationship between specific, well-characterized Yq11 microdeletions and a testicular picture of SCOS, identifying an Y-related region frequently deleted in this syndrome. In conclusion, the findings of this study demonstrate that a large percentage of idiopathic SCOS may be genetically determined and identify an Y-related region that seems to possess one or more still unknown genes essential for spermatogenesis.

Chromosome Deletion↗
PubMed1998

Case report: high fertilization rate in conventional in-vitro fertilization utilizing spermatozoa from an oligozoospermic subject presenting microdeletions of the Y chromosome long arm.

A case is reported in which a high fertilization rate was achieved by conventional in-vitro fertilization (IVF), using spermatozoa from an oligozoospermic man carrying a microdeletion of the long arm of the Y chromosome. The patient presented with idiopathic infertility of 10 years duration; the fertility status of his wife was completely normal. After IVF, five out of eight oocytes retrieved showed normal fertilization and four showed normal embryo cleavage. Four embryos were transferred; however, pregnancy did not result. These results demonstrate that spermatozoa from oligozoospermic patients carrying a Yq microdeletion are fully competent in achieving capacitation, acrosome reaction and fertilizing ability during IVF. Therefore, although definitive conclusions cannot be made from a single case report, we suggest that Yq microdeletion analysis should be considered in oligozoospermic patients undergoing conventional IVF.

Adult↗
PubMed1997

Y-chromosome deletions in idiopathic severe testiculopathies.

A genetic etiology has been recently proposed for some severe forms of idiopathic male infertility and a region of the Y chromosome long arm (Yq) defined AZF is thought to be critical for the regulation of spermatogenesis. To date, two genes, YRRM and DAZ, have been identified in AZF, but the actual relationship between genotype and phenotype related to AZF deletions is not well characterized. By means of a PCR strategy we typed Yq microdeletions in 16 azoospermic and 22 severely oligozoospermic subjects whose testicular cytological picture (assessed by fine needle aspiration) was that of Sertoli cell-only syndrome and severe hypospermatogenesis, respectively. Microdeletions in AZF were found in 37.5% of azoospermic men and in 22.7% of severely oligozoospermic men, suggesting that very frequently these genetic abnormalities determine a severe quantitative defect in spermatogenesis. Furthermore, DAZ and YRRM do not seem to be the sole genes regulating spermatogenesis, as deletions in these genes were observed in only 6 of the 11 deleted cases. No correlation between the spermatogenic defect and the type of Yq deletion exists. Intracytoplasmic sperm injection performed using spermatozoa of these Y-deleted patients will invariably pass this defect onto their male offspring. Screening for deletion within AZF or at least an informed consent should, therefore, be obtained in all idiopathic infertile male undergoing a program of intracytoplasmic sperm injection of a spermatozoon into the oocyte.

Adult↗
PubMed1996

Functional and cytologic features of the contralateral testis in cryptorchidism.

OBJECTIVE: To characterize the testicular cytologic pictures in cryptorchild and contralateral testis related to seminal pattern. DESIGN: Controlled clinical study. SETTING: Andrological and urologic academic setting. PATIENTS: One hundred nine patients orchidopexied because of unilateral cryptorchidism compared with 35 normospermic subjects. INTERVENTIONS: Bilateral testicular fine-needle aspiration cytology. MAIN OUTCOME MEASURES: Seminal parameters; testicular cytologic features; plasma levels of FSH, LH, and T; and ultrasound testicular examination. RESULTS: The cytologic analysis revealed an important quantitative and qualitative impairment of spermatogenic line in all the excryptorchid testes. These alterations are present in the contralateral testes only when azoospermia or severe oligozoospermia were observed, whereas in moderate oligozoospermic subjects a normal tubular status was evident. A compensatory activity in normally descended testis of normozoospermic patients was present. CONCLUSIONS: In unilateral cryptorchidism, a frequent testicular damage in the orchidopexied and in the contralateral descended testis suggests that this condition is the end point of different pathological conditions, including testicular intrinsic (congenital) and extrinsic (anatomical) causes. Fine-needle aspiration cytology of both testes represents a tool in the assessment of the tubular status in excryptorchid subjects.

Adolescent↗
PubMed1995

Diagnostic and clinical features in azoospermia.

BACKGROUND AND OBJECTIVE: The recent advances in assisted fertilization and gamete micromanipulation techniques have enabled fertilization in some forms of azoospermia; for example, epididymal sperm aspiration in obstructive azoospermia. Therefore knowledge of the specific degree of testicular damage is of primary importance, since other clinical parameters, such as FSH plasma levels and testicular volume, do not discriminate between the different testiculopathies. In order to further characterize the specific testicular conditions present in azoospermia, we have examined a large group of azoospermic subjects on the basis of testicular cytological analysis obtained by fine needle aspiration. DESIGN AND PATIENTS: One hundred and twenty-two infertile, azoospermic men were studied by physical examination, FSH radioimmunoassay, testicular ultrasound examination and fine needle aspiration of the testes. Thirty-five infertile normozoospermic subjects were studied as controls. RESULTS: The cytological analysis identified five different sub-types in azoospermic subjects: I, Sertoli cell-only syndrome; II, hypospermatogenesis; III, spermatogonial and/or spermatocytic arrest; IV, spermatidic arrest; and V, normal germ line. The testicular volume was reduced in groups I and II, while the FSH plasma levels were increased in groups I, II and III, suggesting a primary role of spermatids in the control of FSH secretion. CONCLUSIONS: In azoospermic subjects, testicular cytological analysis permits the identification of different sub-types and this classification may be very important in determining therapy, particularly the choice between surgical treatment and the hypothetical use of assisted fertilization techniques by retrieval of epididymal or intratesticular spermatozoa or spermatids.

Adult↗
PubMedDate not supplied

Paracrine and endocrine roles of insulin-like factor 3.

Insulin-like factor 3 (INSL3) is expressed in Leydig cells of the testis and theca cells of the ovary. This peptide affects testicular descent by acting on gubernaculum via its specific receptor leucine-rich repeat-containing G protein-coupled receptor 8 (LGR8). From initial animal data showing the cryptorchid phenotype of Insl3/Lgr8 mutants, an extensive search for mutations in INSL3 and LGR8 genes was undertaken in human patients with cryptorchidism, and a frequency of mutation of 4-5% has been detected. However, definitive proofs of a causative role for some of these mutations are still lacking. More recent data suggest additional paracrine (in the testis and ovary) and endocrine actions of INSL3 in adults. INSL3 circulates at high concentrations in serum of adult males and its production is dependent on the differentiation effect of LH. Therefore, INSL3 is increasingly used as a specific marker of Leydig cell differentiation and function.

Animals↗
PubMedDate not supplied

Identification of functional binding sites for progesterone in rat Leydig cell plasma membrane.

Steroid hormones influence cell functions by binding to intracellular receptors and then acting within the nucleus. There is now evidence that steroids affect cell functions also via interaction with plasma membrane receptors in a number of different cell types. In this regard, progesterone appears to be one of the most active steroids. In this paper, we evaluate the effects of progesterone on rat Leydig cell functions, determining variations of ion homeostasis and testosterone production. This steroid was able to effect a depolarization of the plasma membrane that was due to an influx of sodium (Na+) from the external medium since it was absent when extracellular Na+ was iso-osmotically substituted with choline chloride or sucrose. The determination of intracellular sodium concentration ([Na+]i) with the Na+ -sensitive fluorescent dye sodium-benzofuran-isophtalate (SBFI) confirmed these observations. Progesterone did not modify Leydig cell intracellular calcium concentration ([Ca2+]i) at any dose tested. Furthermore, using a cell impermeant progesterone conjugate, we demonstrated that progesterone was able to stimulate Leydig cell steroidogenesis in a dose-dependent manner. The exclusion of calcium (Ca2+) from the extracellular medium did not modify the depolarizing action of progesterone and its steroidogenetic effect while in Na+ -free medium (sucrose supplemented) progesterone-stimulated effects were completely blunted. Finally, using fluorescence microscopy with a fluorescein isothiocyanate-coupled cell impermeant progesterone conjugate, we identified plasma membrane binding sites for progesterone in rat Leydig cells. These results suggest that rat Leydig cells possess progesterone receptors located on the plasma membrane, which when occupied achieves a plasma membrane depolarization, dependent on an influx of Na+ from the external medium, and the subsequent activation of steroidogenesis.

Animals↗