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Biomedical subjects

A Lenzi

Publications and source records attributed to A Lenzi.

At least 55 records · Page 3Linked to original sources
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

Nuclear chromatin variations in human spermatozoa undergoing swim-up and cryopreservation evaluated by the flow cytometric sperm chromatin structure assay.

The sperm chromatin structure assay (SCSA) is a flow cytometric (FCM) technique which exploits the metachromatic properties of Acridine Orange to monitor the susceptibility of sperm chromatin DNA to in-situ acid denaturation. SCSA was used to study the chromatin structure variations of human spermatozoa in semen, both before and after swim-up and after cryopreservation. Semen samples were provided by 19 healthy normozoospermic subjects attending pre-marriage checks. Each sample was divided into three aliquots: the first aliquot was evaluated without further treatment, the second underwent swim-up, and the third was stored according to standard cryopreservation techniques in liquid nitrogen at -196 degrees C. Samples were also analysed by light and fluorescence microscopy (after Acridine Orange staining to evaluate the number of green fluorescent sperm heads), and by computer-assisted semen analysis. The results showed that post-rise spermatozoa represent a subpopulation characterized by a general improvement of the morphological (reduction of the percentage of abnormal forms and heads, increase of the green head sperm percentage) and kinetic parameters. This subpopulation also exhibited improved chromatin structure properties, confirming that these cells have the best structural and functional characteristics, indicative of optimal fertilizing ability. On the other hand, overall sperm quality deteriorates after cryopreservation. When thawed spermatozoa underwent an additional swim-up round, a general improvement of nuclear maturity was seen in the post-rise spermatozoa.

Adult↗
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↗
PubMed1998

Follicular fluid and human granulosa cell cultures: influence on sperm kinetic parameters, hyperactivation, and acrosome reaction.

OBJECTIVE: To evaluate the influence of human granulosa cell (GC) cultures and follicular fluid (FF) on sperm kinetic parameters, hyperactivation, and the acrosome reaction compared with the influence of human tubal fluid (HTF) and Ham's F-10 medium. DESIGN: Sperm kinetic parameters, hyperactivation, and the acrosome reaction were evaluated after 6 hours of incubation in HTF, Ham's F-10 medium, FF, and GC cultures. SETTING: Infertility and In Vitro Fertilization Centre, Reproductive Endocrinology Unit, Institute of Obstetrics and Gynaecology. PATIENT(S): Sixteen normal semen samples. INTERVENTION(S): Sperm kinetic parameters and hyperactivation were analyzed using an automated videomicrography system, the acrosome reaction was performed using a triple-stain technique, and progesterone and 17OH-progesterone levels were measured with the use of commercially available kits. MAIN OUTCOME MEASURE(S): Sperm kinetic parameters, hyperactivation, acrosome reaction. RESULT(S): The percentage of motile sperm, the mean curvilinear velocity, and the mean of the maximum amplitude of lateral head movement were increased significantly after 6 hours of incubation in FF or GC cultures compared with incubation in HTF or Ham's F-10 medium, whereas the mean linearity was decreased significantly. Follicular fluid and GC cultures significantly increased hyperactivation and the acrosome reaction compared with the values obtained using HTF and Ham's F-10 medium. Progesterone and 17OH-progesterone levels were increased significantly after incubation in FF and GC cultures compared with HTF and Ham's F-10 medium. CONCLUSION(S): Follicular fluid and GC cultures increase sperm motility parameters, hyperactivation, and the acrosome reaction. This effect may be related to GC detoxification of the microenvironement or GC secretion of peptides, glycoproteins, growth factors (insulin-like growth factors 1 and 2), or steroids (progesterone and 17OH-progesterone).

17-alpha-Hydroxyprogesterone↗
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

Results of long-term carcinogenicity studies of chlorine in rats.

Four groups, each of 50 male and 50 female Sprague-Dawley rats, of the colony used in the Cancer Research Center of Bentivoglio of the Ramazzini Foundation, 12 weeks old at the start of the study, received drinking water containing sodium hypochlorite, resulting in concentrations of active chlorine of 750, 500, and 100 mg/l (treated groups), and tap water (active chlorine < 0.2 mg/l) (control group), respectively, for 104 weeks. Among the female rats of the treated groups, an increased incidence of lymphomas and leukemias has been observed, although this is not clearly dose related. Moreover, sporadic cases of some tumors, the occurrence of which is extremely unusual among the untreated rats of the colony used (historical controls), were detected in chlorine-exposed animals. The results of this study confirm the results of the experiment of the United States National Toxicology Program (1991), which showed an increase of leukemia among female Fischer 344/N rats following the administration of chlorine (in the form of sodium hypochlorite and chloramine) in their drinking water. The data here presented call for further research aimed at quantifying the oncogenic risks related to the chlorination of drinking water, to be used as a basis for consequent public health measures.

Animals↗
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↗
PubMed1997

Antisperm antibody detection: 2. Clinical, biological, and statistical correlation between methods.

PROBLEM: In clinical andrology, the detection of antisperm antibodies (ASA) is regarded as one of the most important steps in the study of male infertility. This practice is generally accepted even though there is still some disagreement about the true meaning of antisperm immunity, and there remains 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. The aim of the present paper is to report our studies on the correlation between direct methods (IBT, MAR test) and indirect methods (gelatin agglutination test [GAT], and tray agglutination test [TAT]) and to establish whether biological models can explain the antibody test results. An attempt was also made to establish a "predictive threshold" to explain even apparently discordant direct and indirect results.

Agglutination Tests↗
PubMed1997

Comparison of aggressive behavior between men and women in sport.

A group of 33 sportsmen and 43 sportswomen and a group of 488 subjects (less than 30 years old) selected from a sample of 816 subjects representative of the general Italian population were compared using the factor scores and total scores on the Italian version of the Buss and Durkee questionnaire. Analysis suggests a positive correlation between aggressiveness and sport and are compatible with the hypothesis that sporting activities serve as a means of controlling aggressiveness of women and help the individual psychosocial development of men. The decision to practice sports would seem to be connected with the needs to conform to cultural stereotypes, which portray the man as aggressive and the women as gentle and submissive.

Adolescent↗
PubMed1996

Effects of prolonged autovehicle driving on male reproduction function: a study among taxi drivers.

This study had the purpose of exploring the possible association between the work exposures of professional drivers and their reproductive health, by studying a group of 201 taxi drivers in the city of Rome. Data on work and reproductive history were collected by interviews. Biological markers examined in 72 subjects included salivary testosterone levels, sperm quality (i.e., sperm concentration, sperm morphology, and motility), and fertility experience, including time to pregnancy. Their spermatologic profile was compared with that of a control group of 50 healthy subjects of similar age and smoking habits. The results showed that taxi drivers, compared to the controls, had a significantly lower prevalence of normal sperm forms (45.8% vs. 64.0%); this was particularly true for those with a longer time on this job. This result was confirmed by a multivariate analysis in which confounders such as age, smoking, and alcohol consumption were controlled. The other sperm parameters did not differ in the study and the control groups. Among the life-style factors, we found smoking to be associated with poorer sperm morphology. Moderate alcohol consumption was associated with a better seminologic profile, while the pattern in respect to coffee intake was inconclusive. Subjects with poor semen quality also more frequently exhibited longer time to pregnancy of their partner. The results suggest that prolonged urban automobile driving might be a risk factors for sperm quality, and particularly for sperm morphology, but the finding needs further confirmation.

Adult↗
PubMed1996

Luteinizing hormone pulsatility and computer-assisted analysis of sperm features in patients with Hodgkin's disease.

The aim of this work was to characterize further the impairment of the reproductive function reported in untreated male patients with Hodgkin's disease. We evaluated the pattern of luteinizing hormone pulsatility and unconventional sperm features by computer-assisted sperm analysis (CASA) in 20 adult patients affected by biopsy-proven Hodgkin's disease before they were submitted to any therapeutic approach. Changes of luteinizing hormone pulsatility were documented and consisted mainly in an increase in pulse number in comparison with control subjects (P < 0.05). On CASA, 1/3 of the patients showed a reduction in the sperm number but, when motility, velocity and linearity of progression were evaluated, the number of patients with seminal alterations rose to 2/3. Sperm velocity and linearity were already impaired in stages I and II, whereas sperm number was reduced only in stage III. Symptomatic patients, regardless of the stage, showed a significant deterioration of all parameters. Our study supports the view that in Hodgkin's disease, before any treatment, a disorder of the reproductive system is present, both at hypothalamic/hypophysial and the gonadal level, having a pathogenesis that deserves to be elucidated by further study.

Adult↗
PubMed1995

Environmental tobacco smoke: nicotine and cotinine concentration in semen.

Forty-three nonsmokers attending an infertility clinic reported their degree of passive exposure to environmental tobacco smoke (ETS) and provided samples of blood and seminal plasma. Levels of nicotine and cotinine in biological fluid were evaluated by a radioimmunoassay. The data indicate that exposure to ETS results in measurable nicotine and cotinine levels in seminal plasma. Seminal plasma cotinine concentration also shows a significant positive correlation with degree of reported exposure.

Adult↗