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G Collodel

Publications and source records attributed to G Collodel.

At least 19 recordsLinked to original sources
PubMed2006

TEM, FISH and molecular studies in infertile men with pericentric inversion of chromosome 9.

Pericentric inversions involving the secondary constriction (qh) region of chromosome 9 are considered to be normal variants of human karyotype. A number of investigators have suggested that chromosomal anomalies can contribute to human infertility causing spermatogenetic derangement. The present study was aimed at verifying the influence of chromosome 9 inversion on human spermatogenesis. Semen samples of 18 male carriers of chromosome 9 inversion, analysed by light microscopy, revealed that five patients were azoospermic. PCR analysis demonstrated that two of them also had Y microdeletions. The other 13 showed generally normal sperm concentrations and reduced motility. The morphological characteristics of sperm were studied by TEM and the data were elaborated by a mathematical formula. Sperm pathologies resulted more frequently in the studied group compared to controls, particularly apoptosis. Partial sequences of the A-kinase anchoring protein (Akap) 4 and 3 genes were performed in all patients, as a previous study by our group highlighted Dysplasia of Fibrous Sheath (DFS) defect in two men with inv 9 investigations. The possible effect of chromosome 9 inversion on meiotic chromosome segregation was investigated by FISH, which showed an increased incidence of diploidy. We hypothesized that this inversion could have variable effects on spermatogenesis, from azoospermia to severely altered sperm morphology, motility and meiotic segregation.

Adolescent↗
PubMed2006

Transmission electron microscopy, immunocytochemical and fluorescence in situ hybridisation studies in a case of 100% necrozoospermia: case report.

We present the ultrastructural, functional and chromosomal analyses of sperm from an infertile man with a normal karyotype and 100% necrozoospermia. Tests for microbial infection showed the presence of Escherichia coli in seminal and urethral fluid. Semen analysis was performed concomitantly with the infection and repeated twice after the therapy, in the absence of infection, to control the possible recovery of necrozoospermia. Morphological sperm evaluation was performed by light, fluorescent and electron microscopy; meiotic segregation was examined by fluorescence in situ hybridisation (FISH) technique. Polymerase chain reaction (PCR) was carried out on DNA from peripheral blood lymphocytes to analyse partial sequences of the Akap4 and Akap3 genes. AKAP3 protein is synthesised in round spermatids, incorporated into the fibrous sheath and is involved in organising the basic structure of the fibrous sheath. AKAP4 protein is incorporated late in spermatid development and plays a major role in completing fibrous sheath assembly. The whole sperm population was immotile and non-viable. The ultrastructural characteristics of sperm necrosis were identified. Immunostaining of tubulin and AKAP4 proteins was negative in sperm tails. PCR did not reveal any deletions in the investigated regions. FISH sperm analysis highlighted an altered meiotic segregation. After recovery from infection, 100% necrozoospermia persisted and chromosomal sperm aneuploidies were still present.

A Kinase Anchor Proteins↗
PubMed2006

Sperm morphology and aneuploidies: defects of supposed genetic origin.

As individuals with genetic sperm defects are intracytoplasmic sperm injection candidates, the study of the chromosomal constitution of their spermatozoa is of great interest. This study is a review of the current literature concerning fluorescence in situ hybridisation studies in spermatozoa with genetic sperm defect as 'round head', 'dysplasia of fibrous sheath' (DFS), 'primary ciliary dyskinesia' (PCD), the 'detached tail' and the 'absence of fibrous sheath'. Regarding sperm head defects, elevated XY disomy and diplodies were detected. Genetic defects affecting the sperm tail seemed to have a different correlation with chromosome meiotic segregation. Only chromosome 18, among the autosomes, was studied and the percentage of frequency of disomy was generally within the normal range. In the more frequently studied defect, DFS, the alterations in gonosome disomy and diploidy were recorded by different groups. Regarding PCD defects, elevated frequencies of disomy of sex chromosomes and diploidy were observed, whereas the absence of the fibrous sheath and the detached tail did not show any meiotic disturbance. The problem of genetic sperm defects should be seriously considered when these sperm are used for assisted reproduction, owing to the high risk of transmission of chromosomal imbalance and of mutations that could cause genetic sperm defects in offspring.

Aneuploidy↗
PubMed2005

Gene deletions in an infertile man with sperm fibrous sheath dysplasia.

BACKGROUND: Asthenozoospermia may sometimes be related to genetic structural defects of the sperm tail detectable by transmission electron microscopy. Dysplasia of the fibrous sheath (DFS) is a genetic sperm defect, characterized by dysplastic development of the axonemal and periaxonemal cytoskeleton. We report the case of an infertile man with normal sperm count and total sperm immotility in which dysplasia of the fibrous sheath, Akap3, Akap4 gene deletions, meiotic segregation of chromosomes 18, X and Y and Y microdeletions were investigated. METHODS: A 32-year-old man with a 3-year history of primary infertility presented at our Regional Referral Center for Male Infertility. Family medical history, lymphocyte karyotype, PCR analysis, physical examination, hormone assays and semen analysis were performed. RESULTS: Ultrastructural sperm evaluation showed dysplasia of the fibrous sheath. Immunostaining of AKAP4 protein was negative in sperm tails. PCR analysis revealed intragenic deletions of the Akap3 and Akap4 genes. Fluorescence in situ hybridization on sperm showed a high frequency of XY disomy. CONCLUSION: In this infertile patient, our results suggest a possible relationship between dysplasia of the fibrous sheath, partial deletions in the Akap3 and Akap4 genes and absence of AKAP4 protein in the fibrous sheath. These findings, however, were not detected in another four patients with dysplasia of the fibrous sheath. Our results require future confirmatory molecular analyses.

A Kinase Anchor Proteins↗
PubMed2005

Ultrastructural studies of spermatozoa from infertile males with Robertsonian translocations and 18, X, Y aneuploidies.

BACKGROUND: In order to clarify the relationship between chromosomal rearrangements, sperm morphology and interchromosomal effects (ICE), we studied the spermatogenetic defects in seven infertile Robertsonian translocation carriers. METHODS: Lymphocyte karyotypes were evaluated using Giemsa-Trypsin-Giemsa banding and fluorescence in-situ hybridization (FISH). Semen analysis was performed by light and transmission electron microscopy. FISH of sperm nuclei was carried out to detect possible ICE. RESULTS: Lymphocyte karyotype analysis revealed five t(13;14), one t(13;21) and one t(14;22) carriers. Sperm ultrastructural examination highlighted a higher percentage of immaturity, apoptosis and necrosis than in controls. Aneuploidies of gonosomes were detected in sperm from five out of six carriers of Robertsonian translocation, whereas aneuploidy of chromosome 18 was evident in three out of six carriers. The frequencies of diploidy were altered in all cases. CONCLUSIONS: Since these infertile patients showed severe spermatogenetic impairment from the morphological and meiotic points of view, we recommend detailed sperm ultrastructural and chromosomal analysis before undertaking ICSI cycles in Robertsonian translocation carriers.

Adult↗
PubMed2005

Effect of hyaluronic acid (MW 500-730 kDa) on proteoglycan and nitric oxide production in human osteoarthritic chondrocyte cultures exposed to hydrostatic pressure.

OBJECTIVE: This study investigated the in vitro effects of hyaluronic acid (HA) of molecular weight (MW) 500-730 kDa on human articular chondrocytes cultivated for 48 h in the presence of interleukin-1beta (IL-1beta) with and without hydrostatic cyclical pressure. DESIGN: The effects of 10 and 100 microg/ml HA with and without IL-1beta were assessed in the culture medium of cells exposed to pressurization cycles in the form of sinusoidal waves (minimum pressure 1MPa, maximum pressure 5MPa) at a frequency of 0.25Hz for 3h, by the immunoenzymatic method on microplates for the quantitative measurement of human proteoglycans (PG) and by the Griess method for nitrites (NO). Morphological analyses were performed by transmission electron microscopy (TEM) and scanning electron microscopy (SEM). RESULTS: The presence of IL-1beta determines a significant decrease in PG and a significant increase in NO concentrations measured in the culture medium. When the cells are cultured in the presence of IL-1beta and HA at the two concentrations, a statistically significant restoration of PG and a decrease in NO levels are observed. Under pressurization conditions, we observed that the PG concentration in the medium of cells presented a very significant increase in all the conditions used in the study, except for IL-1beta alone. NO production decreased very significantly in the presence of IL-1beta+HA 10 and IL-1beta+HA 100. The results of metabolic evaluation are confirmed by morphological findings obtained by TEM and SEM. CONCLUSIONS: These in vitro studies confirm both the protective role of HA (MW 500-730 kDa), which counteracts the IL-1beta-induced effects, and the importance of pressure on chondrocyte metabolism and morphology.

Adjuvants, Immunologic↗
PubMed2005

Necrosis in human spermatozoa. I. Ultrastructural features and FISH study in semen from patients with uro-genital infections.

Ultrastructural characteristics and meiotic segregation in spermatozoa from twelve patients affected by uro-genital bacterial infections were investigated. The sperm quality was examined by light and transmission electron microscopy (TEM) and fluorescence in situ hybridization (FISH) analysis was performed in eight out of twelve individuals in order to investigate the meiotic behaviour of chromosomes namely gonosomes and chromosome 18. TEM analysis highlighted a severely altered sperm morphology, typical of apoptosis and in particular, necrosis. We define the ultrastructural characteristics of necrosis as involving the acrosome, chromatin, mitochondrial helix, axonemal structure and plasma membrane. Based on our observations, it is possible to hypothesize that infection acts at the testicular level causing sperm death, due to necrosis itself or by necrosis proposed as the final step of apoptosis. Moreover, FISH analysis revealed the presence of altered meiotic segregation in these patients. The high rate of diploidy and gonosomes disomy in our group of patients suggests the possibility of a negative effect of infection and/or inflammation on sperm morphogenesis.

Adult↗
PubMed2005

Necrosis in human spermatozoa. II. Ultrastructural features and FISH study in semen from patients with recovered uro-genital infections.

Inflammation of the male genital tract is a potential cause of male sterility. The quality of spermatozoa from ten patients with recovered uro-genital infections was examined by transmission electron microscopy (TEM); fluorescence in situ hybridization (FISH) was performed on sperm nuclei in six our of ten patients to investigate the frequency of aneuploidies. TEM analysis demonstrated the presence of a high percentage of necrosis in all patients, whereas apoptosis was present in only five of them. Meiotic segregation was altered in all analysed semen samples. Recovery from infections does not seem to coincide with improved sperm quality, probably because a persistent inflammatory state demonstrated by a high percentage of sperm necrosis sometimes associated with the presence of white blood cells (WBC) in the seminal plasma, is present. The effects of infections of the male genital tract could proceed in the absence of microbial agents due to immunological mechanisms involving the pattern of chemical products typical of inflammation. Our results suggest that the presence of necrosis, sometimes associated with apoptosis, could be considered to be an indicator of male genital tract inflammation. However, further studies are necessary to test the correlation between biochemical parameters and ultrastructural and molecular markers of inflammation.

Adult↗
PubMed2005

'Round head' sperm defect. Ultrastructural and meiotic segregation study.

The sperm 'round head' defect, also known as globozoospermia, is an uncommon alteration of sperm morphology generally characterised by 100% round headed sperm totally lacking an acrosome. This alteration is a genetic sperm defect as demonstrated by analysing the incidence of these alterations in a population of infertile men showing a history of consanguinity and cases belonging to the same family. Ultrastructural characteristics and meiotic segregation in spermatozoa from two patients affected by 'round head' sperm defect were investigated. The sperm quality was examined by light and transmission electron microscopy (TEM) and fluorescence in situ hybridization (FISH) analysis was performed in order to investigate the meiotic behavior of chromosomes namely gonosomes and chromosome 18. TEM analysis, mathematically elaborated, clearly diagnosed the 'round head' genetic sperm defect and highlighted at the same time the presence of other phenotypic alterations belonging to pathologies such as immaturity, apoptosis and necrosis. It is possible to hypothesize that round headed sperm could be a 'weak phenotype' allowing the sperm pathologies to overlap with a sperm defect of genetic origin, further compromising fertilizing potential. FISH analysis revealed a positive correlation between globozoospermia and higher disomies of sex chromosomes and diploidies suggesting a higher risk of creating an aneuploid embryo after intracytoplasmic sperm injection.

Adult↗
PubMed2003

10, 15 reciprocal translocation in an infertile man: ultrastructural and fluorescence in-situ hybridization sperm study: case report.

BACKGROUND: 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.

Adult↗
PubMed2002

Recent advances in human sperm pathology.

Electron microscopy is a valuable tool in understanding not only the presence but also the nature of sperm malformation causing human infertility. In the past, we have examined patients affected by severe teratospermia concomitant with andrological pathologies such as varicocele, cryptorchidism, and infection. In particular, we have demonstrated that, in the case of varicocele, a combination of different phenotypic defects typical of immature spermatozoa is present. This general study was carried out on 2000 infertile men who presented for sperm analysis at our laboratory over the course of 10 years. The ejaculate of all of them was examined by electron microscopy, statistically evaluated by a formula created by us (J of Andrology, 1995), and cytogenetically checked by fluorescence microscopy techniques. First of all, this study concerned the techniques of assisted reproduction, i.e. intracytoplasmic sperm injection (ICSI), partial zona disruption (PZD), and in vitro fertilization (IVF). The conclusion was that the evaluation of the sperm quality of males attempting artificial insemination must concern not only motility or staining characteristics but mainly submicroscopical and molecular properties. Moreover, the effect of follicle stimulating hormone (FSH) treatment on human sperm quality has been evaluated by our group testing the ultrastructure and the function of spermatozoa before and after the therapy. Using the sperm as an andrological monitor, it seems that the therapeutic effect of FSH depends on the type of sperm affections. In particular, phenotypic defects as apoptosis and immaturity can be corrected by FSH treatment. More recently, we approached the problem of genotypic sperm infertility. We demonstrated that some very peculiar defects, detected by electron microscopy, show a hereditary transmission having a genetic basis. In fact, they are much more frequent in consanguineous patients, and are clearly related to different degrees of consanguinity. Frequently, chromosomal translocations have sometimes been found correlated to these defects.A consequence of these demonstrations is that most of the present sperm defects are phenotypic and can be submitted to surgical or pharmaceutical cares, but others have genetic origin and cannot be corrected by surgical or pharmaceutical treatment. These malformations are transmitted to the offspring by techniques of assisted fertilization.

Consanguinity↗
PubMed2001

Effects of the purified IGF-I complex on the capacitation and acrosome reaction of rabbit spermatozoa.

A protein complex containing IGF-I, purified from rabbit seminal plasma, was used to investigate its effects on the capacitation and acrosome reaction of rabbit spermatozoa. Uncapacitated sperm (Pattern F), capacitated sperm (Pattern B), and acrosome-reacted sperm (Pattern AR) were determined by CTC staining, and the results were validated by PSA-staining. The addition of the IGF-I complex to the capacitative medium directed the spermatozoa to spontaneous acrosome reaction. On the other hand, IGF-I complex, added to capacitated spermatozoa, acted as inducer of the acrosome reaction. Results of IVF experiments showed high rates of fertilization with capacitated spermatozoa, acrosome-reacted by either A23187 or IGF I complex, whereas significantly lower rates were obtained with spermatozoa capacitated in the presence of IGF-I complex.

Acrosome Reaction↗
PubMed2001

Genetic sperm defects and consanguinity.

BACKGROUND: The existence of a genetic component to human infertility has been suggested, although neither the specific abnormalities involved, nor their genetic mechanism of transmission, are currently defined. We have examined, by transmission electron microscopy (TEM), ejaculate from 1600 males with fertility problems. Among the subjects studied, we focused on a group of patients whose family histories revealed different degrees of consanguinity, in order to evaluate the relationship between consanguinity and particular sperm alterations. METHODS AND RESULTS: A total of 64 consanguineous individuals were identified. In this group, excluding two azoospermic patients, 17 patients (27%) were found to have well recognized genetic ultrastructural defects affecting their entire sperm population: eight subjects had spermatozoa with "stunted tails", four "detached tail" spermatozoa, two "Kartagener's syndrome", two "miniacrosome" and one "round headed" spermatozoa. Since these alterations affect the total sperm population and do not respond to medical treatment, they are suspected of having a genetic origin. The remaining group of 1506 non-consanguineous patients suffered from the same genetic defects in only 15 cases (<1%). CONCLUSIONS: From the data presented, it appears that some very peculiar and rare sperm defects may have a genetic basis since they occur more frequently in consanguineous patients, and are related to different degrees of consanguinity. Since the ejaculate of the remaining patients, both consanguineous and not, showed diverse types of ultrastructural sperm anomalies that did not affect the entire sperm population, they might represent pathologies lacking a genetic basis.

Acrosome↗
PubMed2000

Effects of chondroitin sulfate and interleukin-1beta on human chondrocyte cultures exposed to pressurization: a biochemical and morphological study.

Objective This study investigated the in vitro effects of chondroitin sulfate (CS) on human articular chondrocytes cultivated in the presence or in the absence of interleukin-1beta (IL-1beta) during 10 days of culture with and without pressurization cycles. Design The effects of CS (10 and 100 microg/ml) with and without IL-1beta were assessed in the culture medium of cells exposed to pressurization cycles in the form of synusoidal waves (minimum pressure 1 Mpa, maximum pressure 5 Mpa) and a frequency of 0.25 Hz for 3 h by immunoenzymatic method on microplates for the quantitative measurement of human proteoglycans (PG). On the 4th and 10th day of culture the cells were used for morphological analysis by transmission electron microscopy (TEM) and scanning electron microscopy (SEM). Results The presence of IL-1beta determines a significant decrease in PG concentration measured in the culture medium. When the cells are cultured in the presence of IL-1beta and CS, a statistically significant restoration of PG levels is observed. Under pressurization conditions, we observed that PG concentration in the medium of cells presents a significant increase at baseline conditions, in the presence of IL-1beta+CS10 and IL-1beta+CS100, but not with IL-1beta alone. The results concerning metabolic evaluation are confirmed by the morphologic findings obtained by TEM and SEM. Conclusions These in vitro studies confirm the protective role of CS, which counteracts the IL-1beta induced effects and they confirm the importance of pressure on chondrocyte metabolism and morphology.

Aged↗
PubMed1999

Failure of HIV-1 to infect human oocytes directly.

In this study, the susceptibility of mature human oocytes to HIV-1 infection has been investigated. We exposed in vitro human oocytes of healthy women using inocula of cell-free HIV-1. We also tested for the presence of HIV-1-specific receptor molecules on the surface of these cells. By applying polymerase chain reaction (PCR) analysis, transmission electron microscopy (TEM), and immunocytochemistry at both light and electron microscopic levels, we did not obtain evidence for HIV DNA production nor for oocyte-associated HIV particles. Experiments of immunostaining for CD4, CCR5, and GalAAG (putative receptor for HIV in sperm), as well as reverse transcriptase (RT)-PCR for CD4, CCR5, and CXCR4, which all suggested the absence of the mentioned receptors in mature oocytes and in follicular cells. This study fills an important gap concerning the information available on the direct HIV infection of human gametes, adds to our basic understanding of HIV infection in human oocytes, provides different results from those obtained with human spermatozoa using comparable methods, and provides a basic contribution to the investigation on HIV infection in human oocytes.

CD4 Antigens↗
PubMed1998

The debate on the presence of HIV-1 in human gametes.

The debate about the presence of HIV-1 particles in human gametes and recent experimental results are reported in detail. Using immunocytochemistry, in situ hybridization at electron microscopy level, polymerase chain reaction and in vitro fertilization, it has been demonstrated that human spermatozoa can incorporate HIV-1 using special receptors, different from the usual CD4, and that they remain active and able to vehicle the viral particles into the oocyte, which is regularly fertilized. Moreover, by transmission electron microscopy (TEM), immunocytochemistry and PCR, we demonstrated that cell-free HIV-1 is not able to bind and penetrate the human oocyte in vitro. We attribute this behaviour to the fact that the oocyte and cumulus cells are devoid both of GalAAG and of CD4 receptors. PCR analysis indicated that mRNAs specific for CD4, CXCR4 and CCR5 proteins were absent, too.

Animals↗
PubMed1998

Detrimental effects of polyvinylpyrrolidone on the ultrastructure of spermatozoa (Notulae seminologicae 13).

The effect of in-vitro treatment by polyvinylpyrrolidone (PVP) on the ultrastructure of human spermatozoa has been tested previously with the statistical analysis of B. Baccetti et al. (1995, J. Androl., 16, 356-371). PVP had a primary detrimental action on the plasma membrane, as well as on acrosomal and mitochondrial membranes. Furthermore, membrane damage induces deterioration of the chromatin, axonemal tubules, fibrous sheath, and accessory fibres.

Acrosome↗