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Biomedical subjects

F Dondero

Publications and source records attributed to F Dondero.

At least 19 recordsLinked to original sources
PubMed2002

Polyunsaturated fatty acids of germ cell membranes, glutathione and blutathione-dependent enzyme-PHGPx: from basic to clinic.

The lipid metabolism in sperm cells is important both for energy production and for cell structure. A special composition of membrane phospholipids, rich in polyunsaturated fatty acids (PUFA), and the different composition of sperm and immature germ cell membrane are described and discussed. Testis germ cells as well as epididymal maturing spermatozoa are endowed with enzymatic and non-enzymatic scavenger systems to prevent lipoperoxidative damage. Catalase, superoxide dismutase, and glutathione-dependent oxidoreductases are present in variable amounts in the different developmental stages. Phospholipid hydroperoxide glutathione peroxidase (PHGPx) activity and roles in caput and cauda epididymal sperm cells are discussed. Also seminal plasma has a highly specialized scavenger system that defends the sperm membrane against lipoperoxidation and the degree of PUFA insaturation acts to achieve the same goal. Systemic predisposition and a number of pathologies can lead to an anti-oxidant/pro-oxidant disequilibrium. Scavengers, such as glutathione can be used to treat these cases as they can restore the physiological constitution of PUFA in the cell membrane.

Animals↗
PubMed2001

A new objective method for scoring human sperm hyperactivation based on head axis angle deviation.

The aims of the present study were, first to develop a new method for evaluating sperm hyperactivation (HA) based on sperm head axis angle deviation, and second to apply this method in scoring selected sperm populations during capacitation. This was made possible by improving our original superimposed image analysis system (SIAS). The new option on the system enables us to determine the real angular deviation of the entire head in successive superimposed frames. The entire procedure for each spermatozoon requires 10-20 sec, according to the frame/rate utilized. A clear cut-off between the values of hyperactivated, transitional and non-hyperactivated spermatozoa was found at 11 and 21 frames/sec. However, at 6 frames/sec, a partial overlap between the three classes was found. We defined sperm activity as follows. At 11 frames/sec, hyperactivated: angle sum > or = 405 degrees; transitional: 200 degrees < or = angle sum < 405 degrees. At 21 frames/sec, hyperactivated: angle sum > or = 760 degrees; transitional: 350 degrees < or = angle sum < 760 degrees. The results, in agreement with previous research, show the peaks of activity at 3 h, dropping to a minimum at 6 h. This phenomenon was significantly more evident in fertile compared with subfertile semen samples.

Humans↗
PubMed2000

Myth and reality of the decline in semen quality: an example of the relativity of data interpretation.

Many hypotheses have been put forward to explain a suspected decline in semen quality. Up to now many sources of data were used but conflicting results are present in the literature. To study whether modifications of sperm parameters actually exist we used data from two groups of patients checked and two small groups of sperm bank donors selected at the beginning '80s and '90s. We tried to reduce bias to a minimum: all the semen analyses were carried out by the same biologist, using the same methods, groups were clinically evaluated by the same andrological team, the study groups were homogeneous for age, geographic-ethnic origin, residence, monthly-seasonal distribution and abstinence period. Comparing patients from the '80s and the '90s, sperm concentration and motility showed a significant reduction. Furthermore, the decrease in concentration and motility was mainly due to the higher age classes. In donors, no decline was observed. These results seem to indicate that sperm donors remain unaffected, while patients with lower levels of semen quality are experiencing a real decline. Unfortunately, many confounding variables, analyzed in detail in this review, still remain despite efforts at standardization.

Adult↗
PubMed2000

Chromosomal alterations and male infertility.

Reduced male fertility can be caused by genetic factors affecting gamete formation or function; in particular, chromosome abnormalities are a possible cause of male subfertility as shown by their higher frequency in infertile men than in the general male population. Meiotic studies in a number of these males have shown spermatogenesis breakdown, often related to alterations in the process of chromosome synapsis. Indeed, any condition that can interfere with X-Y bivalent formation and X-chromosome inactivation is critical to the meiotic process; furthermore, asynapsed regions may themselves represent a signal for the meiotic checkpoint that eliminates spermatocytes with synaptic errors. We performed cytogenetic, hormonal and seminal studies in 333 infertile patients selected because azoospermic, severely oligozoospermic or normozoospermic with failure to fertilize the partner's oocytes in an in vitro fertilization (IVF) program. Our findings: 1) confirm the high incidence of chromosomal anomalies among infertile males; 2) highlight the relevance in male infertility of quantitative/positional modifications of the constitutive heterochromatin; and 3) underline the relevance of cooperation between andrologists and cytogenetists prior to every kind of assisted reproduction, above all prior to intracytoplasmic sperm injection, in which selective hurdles eliminating abnormal germ cells are bypassed.

Adult↗
PubMed2000

Psychosocial factors and male seminal parameters.

The relationships between (a) alexithymia, (b) extroversion (E), neuroticism (N), psychoticism (P), (c) coping style towards stressors, and seminal parameters, were assessed in 132 males on their first seminal fluid examination by means of a multivariate approach. They were given the TAS-20, the EPQ, and the Coping Inventory for Stressful Situations (CISS). Seminal parameters were: (1) sperm concentration; (2) total sperm count; (3) forward motility; (4) atypical forms. Multiple regressions considering quantitative parameters of seminal status as criterion showed a negative relationship with P, difficulty describing feelings (DDF), while a positive relationship was found for N, and emotion-oriented coping. A discriminant analysis also showed that P, N and DDF distinguished between two groups of normozoospermic and oligozoospermic subjects with a high probability of correct classifications. Results confirm the hypothesis that biological and psychological variables are not completely independent or randomly related in people with an impaired seminal status, although the correlations between psychosocial and biological data are not very strong.

Adaptation, Psychological↗
PubMed2000

Study of apoptotic DNA fragmentation in human spermatozoa.

The aim of our work was to define and better understand apoptosis in the spermatozoa of normal subjects, infertile patients and patients affected by specific tumoral diseases employing the method of the terminal deoxynucleotidyl transferase-mediated dUTP nick-end labelling and confirming the results by electron microscopy. We studied 23 healthy, normozoospermic subjects (group A), 29 oligoasthenoteratozoospermic patients, affected by various andrological pathologies (group B), 28 patients with Hodgkin's disease (C1) and 30 patients with testicular cancer (C2). Our data demonstrate that the percentage of apoptosis in normozoospermic subjects (group A) is significantly lower than in all the other groups (B, C1, C2) (P < 0.001). This confirms that high DNA fragmentation is one of the characteristics of spermatogenetic failure. The induction of apoptosis, which can also be a basic response to neoplastic disease, can even act right up to the mature male gamete. Our results suggest that apoptosis could be the final result of various pathologies and of a deregulation of spermatogenesis control systems.

Adult↗
PubMed2000

Fatty acid composition of spermatozoa and immature germ cells.

A great deal of attention has recently been given to the essential role of polyunsaturated fatty acids (PUFA) of sperm membranes. We studied the fatty acid composition of the immature germ cells (IGC) and of the sperm populations separated by Percoll gradient in the ejaculate of normozoospermic patients. Fatty acid pattern was analysed by combined gas chromatography-mass spectrometry on a capillary column. In IGC, differences were found compared with mature spermatozoa, with a higher percentage of saturated fatty acids and of essential fatty acids. On the contrary, the long-chain PUFA were significantly lower in IGC. The highest concentration of n3 PUFA docohexaenoic acid (DHA) was detected in the spermatozoa deriving from 70-100% Percoll layers and a direct linear correlation was found between the increase of DHA and increased percentage of Percoll gradient. An inverse relationship between the percentage of atypical sperm forms in each layer and the percentage of DHA was also observed. This study demonstrates that the human germ cell line can elongate and desaturate essential fatty acids and that the percentage of long-chain PUFA is correlated with the normal morphology of sperm cells.

Fatty Acids↗
PubMed2000

Azoospermia: incidence, and biochemical evaluation of seminal plasma by the differential pH method.

BACKGROUND: Recent artificial reproductive technologies (ART) have enabled even azoospermic subjects to take part in "in vitro fertilization" programs. The aim of the present study was: a) to evaluate the incidence of azoospermic male partners of infertile couples; b) to determine whether biochemical evaluation of such azoospermic males can help to discriminate between obstructive and secretory azoospermia. METHODS: Semen samples (n. 28,339; period 1990-1997) were analyzed according to WHO guidelines. In addition, in 108 azoospermic subjects, fructose, citric acid and L-carnitine (taken respectively as markers of seminal vesicle, prostate and epididymal function) were assayed using a new, faster technique, the differential pH method. RESULTS: The incidence of azoospermic semen samples was 4.76%. The biochemical analyses were indicative diagnostically, especially with regard to obstructive azoospermia. However, in secretory azoospermia, biochemical analysis of seminal plasma did not offer particularly helpful indications, except in cases of hypogonadism. CONCLUSIONS: Azoospermia accounts for a relatively high number of cases and justifies detailed attention to the diagnostic and therapeutic approach. Biochemical analysis of the seminal markers is a valid support for differential diagnosis between secretory obstructive azoospermia. It can therefore help in the correct recruitment of such patients for ART programs.

Biochemistry↗
PubMed1999

Immature germ cell separation using a modified discontinuous Percoll gradient technique in human semen.

The difficulty of identifying immature germ cells in unstained, fresh semen has led most laboratories to use the broad definition 'round cells' to indicate cells other than spermatozoa, thus grouping together both leukocytes and immature germ cells. This is also the case in research andrology, where very little attention has been given to immature germ cells in the semen apart from some rare exceptions, such as the attempts to study meiosis. Here we report on the use of a discontinuous Percoll gradient method modified to enable the best separation possible of immature germ cells from the other cells found in the ejaculate, in order to obtain a cellular suspension free of spermatozoa. Our technique (intra-assay variation in duplicates < 10%) demonstrated a high immature germ cell concentration in gradient fractions with 30% to 45% Percoll with a small contamination (1.5-6%) of leukocytes, confirmed by May-Grünwald-Giemsa staining, immunofluorescence and cytofluorimetry. The concentrations of immature germ cells ranged from zero in obstructive azoospermia to 2.0 x 10(6)/ml in oligozoospermia and genital tract infection. The purified immature germ cell suspensions obtained can be useful for diagnostic and research purposes.

Cell Separation↗
PubMed1999

[Intra-spermatic L-carnitine and survival of sperm motility].

BACKGROUND: The aim of this work was to evaluate the intrasperm carnitine (L-C) content related to sperm motility survival in bovine cervical mucus and in culture medium (Tyrode solution). METHODS: The following subjects were selected: 15 fertile normospermic subjects (according to WHO guidelines) and 31 male partners of infertile couples (semen profile: volume > 2.0 ml; concentration > 20 x 10(6)/ml, progressive motility > or = 25% (WHO categories "a" and "b") after fluidification, abnormal forms < 70%; round cells < 1.0 x 10(6)/ml). After standard semen analysis, the samples were subdivided into three aliquots in order to carry out: a) intrasperm L-C (free, total and acetylated) assay; b) sperm motility survival in bovine cervical mucus; c) sperm motility survival in culture medium. RESULTS: A strict correlation was found between L-C (total and acetylated) content and motility survival in cervical mucus. This is probably due to the fact that in cervical mucus lipids are an important energy source for sperm and to metabolize these lipids intrasperm L-C is essential. Therefore, L-C content can be considered as an indicator of sperm motility life-span in cervical mucus. A significant correlation, even if reduced compared with cervical mucus, was also observed between L-C (total and acetylated) content and sperm motility survival in the biological medium. This probably is because the L-C system modulates the reserves of free CoA, essential to the tricarboxylic acid cycle function. CONCLUSIONS: The intrasperm L-C deficit could be due to; a) alterations in the L-C uptake mechanisms in the epididimys due to inflammatory processes; b) lack of testosterone (L-C uptake is androgen-dependent). Therefore, the therapeutic implication of this finding is that where hypomotility is due to intrasperm L-C deficit, exogenous L-C administration or improvement of L-C epididymal testosterone-dependent uptake could promote the acquisition of sperm motility.

Animals↗
PubMed1999

Is hyperdiploidy of immature ejaculated germ cells predictive of testis malignancy? A comparative study in healthy normozoospermic, infertile, and testis tumor suffering subjects.

The possibility of diagnosing neoplastic testis pathologies by studying immature germ cells released from the seminiferous epithelium and present in the semen has been reported. It has been suggested that carcinoma in situ (CIS) of the testis and testis tumor may be identified by studying specific surface antigenic determinants or ploidy of chromosome 1 of malignant germ cells recovered from the semen. A noninvasive diagnostic approach of this type would be of great interest if we consider that CIS is supposed to precede the development of testicular germ cell tumors and that the frequency of that preneoplastic condition is increased in specific andrologic pathologies. To evaluate the reliability of this diagnostic approach, we have quantified the presence of immature hyperdiploid germ cells in the seminal fluid of normal healthy subjects, of infertile oligozoospermic patients affected by maldescended testis or left vancocele, and of patients suffering from CIS or testis tumor. Cell ploidy was evaluated on seminal cell fractions highly enriched in immature germ cells, by means of in situ hybridization with a DNA-probe specific for chromosome 1. Our observations indicate that chromosome 1 hyperdiploidy is not necessarily a predictive parameter of testis tumoral pathologies. The percentage of hyperdiploid immature seminal germ cells is in fact increased in nontumoral pathologies associated with infertility, such as cryptorchidism and left varicocele.

Adult↗
PubMed1999

Semen analysis and seminal plasma biochemistry in two brothers with familial reciprocal translocation 46,XY,t(8;9)(p10;p10) transmitted by the father.

Here we report familial balanced translocation (46,XY,t(8;9)(p10;p10) inherited by two brothers from the father. The first subject, 33 years old, was examined after 3 years of childless marriage. Semen analysis showed severe oligozoospermia, hypomotility and teratozoospermia. His brother, 29 years old, volunteered to join this study. He had not yet tried to start a family. Semen analysis showed dyspermia, but the condition was much less serious than his brother's. In both subjects, the secretory function of the epididymis and the genital tract accessory glands did not seem to be affected by this particular translocation. This case report highlights the importance of cytogenetic analysis in dealing with infertile patients suffering from severe dyspermia apparently sine causa. This is particularly the case when certain Assisted Reproductive Technology (ART) programs are recommended, where natural selection of the sperm no longer takes place (e.g. ICSI). The possible risk of an increase in fetal chromosomal abnormalities would suggest genetic counselling in all such situations.

Adult↗
PubMed1998

Sperm parameters after early left varicocele treatment.

OBJECTIVE: We evaluated whether early treatment for left varicocele can improve sperm parameters. DESIGN: Patient follow-up and comparison with control groups. SETTING: Surgical department of a Children's Hospital and a university infertility-care center. PATIENT(S): Nineteen patients who underwent surgery for left varicocele as adolescents (mean +/- SD, 14.11 +/- 1.59 years) were followed up as adults (mean +/- SD, 19.37 +/- 1.16 years). MAIN OUTCOME MEASURE(S): A testicular examination was performed and varicocele staging was done at the time of surgery. Andrologic examination and semen analysis were done 2-8 years later. Semen results were compared with those of two age-matched control groups of 19 healthy, randomly selected subjects and 19 unoperated patients suffering from left varicocele of the same degree. RESULT(S): The mean values of sperm parameters in the patient study group were similar to those of the healthy controls except that the sperm concentration was significantly lower. However, sperm motility and morphology mean values in the patient study group were significantly higher than those of the unoperated patients. CONCLUSION(S): This study indicates that surgery in adolescence can be useful, possibly because the testis is developing at that age. Large-scale, double-blind controlled trials on early treatment of left varicocele are needed to identify possible markers of disease severity.

Adolescent↗
PubMed1997

The application of the differential pH method to the biochemical evaluation of seminal plasma.

OBJECTIVE: To apply the differential pH method to the biochemical evaluation of seminal plasma. DESIGN AND METHODS: Fructose, citric acid and free L-carnitine concentration in human seminal plasma were measured by the differential pH method. These are routinely taken as markers of seminal vesicle, prostate and epididymal function, respectively. The pH differential method was then compared with standard spectrophotometry. RESULTS: The linearity, recovery and imprecision calculation for each assay were found to be reliable and the method correlated well with the reference spectrophotometric technique. In addition, the pH differential method showed certain advantages compared to spectrophotometry: a) speed of procedure (40 to 120 sec/assay); b) ability to measure the analytes even in small volumes of seminal plasma (10 microL to 50 microL) without deproteinization or dilution, thus eliminating manual operations. CONCLUSIONS: The differential pH method is an innovative approach to the biochemical assessment of seminal plasma.

Carnitine↗
PubMed1997

Unilateral cryptorchidism corrected in prepubertal age: evaluation of sperm parameters, hormones, and antisperm antibodies in adult age.

OBJECTIVE: To evaluate whether prepubertal orchidopexy for unilateral cryptorchidism can reduce adult dysspermia. DESIGN: Patient follow-up comparison with control groups. SETTING: Surgical and endocrinologic sections of a children's hospital and a university infertility-care center. PATIENT(S): Seventy-one patients with unilateral cryptorchidism who underwent orchidopexy in prepubertal age (6.4 +/- 2.8 years) were followed up as adults (20.0 +/- 2.8 years). MAIN OUTCOME MEASURE(S): Patients underwent testicular examination and hormonal evaluation, 49 of these had semen analysis and antisperm antibody tests. Semen results were compared with those of two age-matched control groups: a group of 20 healthy, randomly selected subjects and a group of 20 patients operated on in postpubertal age for cryptorchidism. RESULT(S): Unilateral reduced testis size was found in 30.1% of patients, eight patients had a low LH level, eight had a low T level, and none had abnormal FSH values. Antisperm antibodies were found in 1 of 49 cases. Cluster analysis of sperm parameters showed that the mean values of patients were worse than those of the healthy controls but better than those of the subjects operated on in postpubertal age. CONCLUSION(S): This study indicates that prepubertal orchidopexy can given better results than postpubertal correction.

Adult↗
PubMed1997

The in-vitro effects of nicotine and cotinine on sperm motility.

Swim-up spermatozoa from the seminal samples of non-smokers, usually not exposed to passive smoking, were treated in vitro with nicotine (NIC) and cotinine (COT) at the average levels found in smokers' seminal plasma and at levels 500 times higher than this average. This was done to evaluate the action of these drugs on sperm motility. Each sample was allowed to swim up in Tyrode's solution with or without the drug; the study was carried out at time 0 and +1, +2, +4, +8 and +24 h of incubation, using a light microscope and a CASA system (experiment 1). In addition, the direct action of smoke on spermatozoa was studied using aspirated cigarette smoke (experiment 2). Kinetic parameters were then measured at 30 min, 45 min and 60 min starting from the last smoke injection. The first experiment showed that NIC and COT at average levels did not produce statistically significant variations of the kinetic parameters studied up to 24 h. However, the much higher concentration significantly altered all the kinetic variables in relation to the time of incubation. The second experiment with smoke in toto demonstrated a sharp reduction in all the sperm kinetic parameters. This reduction was seen after 30 min exposure to smoke and increased progressively until almost complete immotility at 1 h of exposure. These results suggest that NIC and COT are not responsible for the harmful effects of cigarette smoke on sperm kinetic parameters reported in the literature.

Adult↗
PubMed1997

Antisperm antibody detection: 1. Methods and standard protocol.

PROBLEM: Today, antisperm antibody (ASA) detection is one of the most important steps in the evaluation of male infertility. This practice is generally accepted even though there is still some disagreement about the meaning of antisperm immunity and a good deal of controversy about the test regarded as the most suitable for the detection of antibodies directed against sperm antigens. International workshops have tried to standardize universally accepted protocols. A panel of three or four methods is generally advised to provide a correct and complete screening of patients with antisperm immunity. METHOD OF STUDY: This paper reports on the results of a serum exchange workshop for the standardization of the ASA detection in the sera carried out under the auspices of the Italian Society of Endocrinology, which was used as reference laboratory. A careful description of the most widely used methods is reported and proposed as a standard protocol also on the basis of the results of the correlation studies carried out by our group is also reported. CONCLUSIONS: If the proposed methods and procedures will be accepted by the members of the Alps-Adria Society for Immunology of Reproduction, a Study Group for Sperm Antibody Testing, could start its activity having the goal of reaching a consensus on methodology and carrying out a European serum exchange workshop.

Agglutination Tests↗