Biomedical subjects

Nunziata Barone

Publications and source records attributed to Nunziata Barone.

5 recordsLinked to original sources

PubMed2005

Patients with abnormal sperm parameters have an increased sex chromosome aneuploidy rate in peripheral leukocytes.

BACKGROUND: Patients with oligoasthenoteratozoospermia (OAT) and normal karyotypes have an increased sperm aneuploidy rate. This may be due to an altered intratesticular environment that affects the chromosomal segregation mechanism(s). Alternatively, it may be due to a generalized meiotic and mitotic abnormality. In this case, patients with abnormal spermatogenesis should also have an increased somatic cell aneuploidy rate. To test this hypothesis, we evaluated peripheral leukocyte aneuploidy rate in patients with spermatogenic impairment. METHODS: In all, 38 patients were enrolled, of whom 20 had OAT, 15 non-obstructive azoospermia and three Y chromosome (Yq) microdeletions (AZF). Eight healthy normozoospermic men with proven fertility were recruited as controls. Conventional karyotype analysis, AZF microdeletion evaluation and triple-colour FISH for chromosomes X, Y and 12 were conducted in all patients and controls. A total of 1000 lymphocytes were scored for each patient and control. RESULTS: All patients and controls had a normal karyotype. Sex chromosome aneuploidy rates in peripheral lymphocytes was significantly higher in patients with OAT (0.74+/-0.09%), azoospermia (1.15+/-0.15%) or Yq microdeleted (1.54+/-0.40%), compared with controls (0.15+/-0.03%) (P <0.05). CONCLUSIONS: Patients with OAT, azoospermia or Yq microdeletions had a slight, but significant, increase of sex chromosome aneuploidy rate in lymphocytes, suggesting the presence of a generalized defective cell division mechanism. In contrast with recent observations, Yq microdeletions do not seem to predispose to a higher number of malsegregation events in somatic cells compared with patients with azoospermia.

Adult↗

PubMed2004

Normal expression of isoforms activating cyclic adenosine monophosphate responsive element modulator in patients with spermatid maturation arrest.

OBJECTIVE: To evaluate whether defective cyclic adenosine monophosphate responsive element modulator (CREM) expression is the causative factor of spermatid maturation arrest (SMA). DESIGN: Comparative evaluation of the testicular histology in patients with SMA or normal spermatogenesis. SETTING: University clinic of andrology. PATIENT(S): Azoospermic patients undergoing testicular biopsy. INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): Expression of CREMtau in quantitative immunohistochemistry analysis of testicular biopsy samples. RESULT(S): Regular CREM expression was observed in the tubules with round, but not elongated, spermatids of patients with SMA (n = 9). Quantitative analysis showed that round spermatids of patients with SMA had a staining intensity similar to that observed in controls (n = 7). CONCLUSION(S): Lack of spermatid elongation was not due to defective CREM expression. Therefore, CREM did not play a pathogenetic role in the onset of SMA in humans.

Biopsy↗

PubMed2004

Expression of SPANX proteins in human-ejaculated spermatozoa and sperm precursors.

The sperm protein associated with nucleus in the X chromosome (SPANX) gene family is constituted by only a few members, clustered at Xq27, encoding small proteins which range from 15 to 20 kDa. These proteins have been shown to be present both in mature spermatozoa and in tumours, such as melanoma and some leukaemias. We developed polyclonal sera in order to study the distribution of the protein in human-ejaculated spermatozoa and their precursors. A synthetic peptide was designed from a domain common to the SPANX protein family and polyclonal sera were raised in mice. Seven healthy volunteer men with normal sperm parameters were recruited and the expression of SPANX proteins was evaluated in spermatozoa and ejaculated sperm precursors by immunocytochemistry and immunofluorescence analyses. SPANX proteins, present in a large fraction (96%) of mature spermatozoa, were localized in the sperm head (39.2%), midpiece (22.8%) or in both sites (34.4%). Spermatids also showed the presence of SPANX proteins in their cytoplasm, although a significantly higher number of spermatids were SPANX-negative compared with spermatozoa. In conclusion, SPANX proteins are expressed in an elevated percentage of spermatids and mature spermatozoa. In the latter, they are preferentially located in the sperm head. The greater number of SPANX-negative spermatids observed could relate to their easier exfoliation from the seminiferous tubules.

Amino Acid Sequence↗

PubMed2002

Chromosome analysis of epididymal and testicular spermatozoa in patients with azoospermia.

Azoospermic patients can now father children once spermatozoa have been retrieved from the epididymis or the testis. However, there are concerns about the risk of chromosomal abnormalities since an increase in sperm aneuploidy rate has been reported in samples from patients with abnormal sperm parameters. The purpose of this study was therefore to evaluate the sperm aneuploidy and diploidy rates for chromosomes 8, 12, 18, X and Y in spermatozoa extracted from the epididymes (n=10) or the testes (n=6) of patients with azoospermia. Ejaculated spermatozoa of healthy men (n=14) served as control. Epididymal and testicular spermatozoa had an aneuploidy rate significantly higher than that found in ejaculated spermatozoa. The aneuploidy and diploidy rates of testicular spermatozoa were higher, but not significantly different, than those found in epididymal spermatozoa. This study has shown that azoospermic patients have an increased sperm aneuploidy rate. They should therefore be given appropriate genetic counselling before entering in-vitro fertilisation programs.

Adult↗

PubMedDate not supplied

Absolute polymorphic teratozoospermia in patients with oligo-asthenozoospermia is associated with an elevated sperm aneuploidy rate.

Infertile patients with abnormal sperm parameters have an increased sperm aneuploidy rate, despite a normal blood karyotype. The evaluation of sperm chromosome aberrations in patients with teratozoospermia only has shown a rate similar to that found in patients exhibiting oligo-astheno-teratozoospermia, which suggests that teratozoospermia is the critical parameter associated with aneuploidy. However, it is not known which alteration of the sperm morphology is associated with chromosome aberrations. The few cases reported so far have shown an association with the presence of abnormal head morphology and particularly with enlarged heads. We report the sperm aneuploidy rate of 3 patients with oligo-asthenozoospermia who have absolute teratozoospermia (100% abnormal forms) and a different percentage of sperm head abnormalities. Fourteen healthy men with normozoospermia served as control subjects. Sperm aneuploidy and diploidy rates were calculated by using triple-color fluorescence in situ hybridization (FISH) for chromosomes 12, X, and Y, and double-color FISH was used for chromosomes 8 and 18. Patient K53, who had the highest number of spermatozoa with enlarged heads (54.3%), also had the highest aneuploidy and diploidy rates. The other 2 patients, K56 and K61, had sperm aneuploidy and diploidy rates lower than those of patient K53 but still well above the range found in normal men. Sperm chromosome abnormalities were intermediate in patient K61 and lower in patient K56, who had the lowest rate of spermatozoa with enlarged heads (18.9%). These data add further evidence that patients with teratozoospermia have an increased sperm aneuploidy rate and that this is particularly high in presence of an elevated percentage of spermatozoa with enlarged heads. For this reason, germ cells exhibiting this abnormality should not be used in in vitro fertilization programs.

Adult↗