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E Greco

Publications and source records attributed to E Greco.

At least 37 records · Page 2Linked to original sources
PubMed2000

In-vitro spermatogenesis resumption in men with maturation arrest: relationship with in-vivo blocking stage and serum FSH.

We have shown previously that germ cells recovered from some men with maturation arrest can resume spermatogenesis in vitro and give rise to late elongated spermatids. This study relates the ability of germ cells to differentiate in vitro to the stage at which spermatogenesis is blocked in vivo and to the patient's serum FSH concentration. The presence of germ cells at different stages of spermatogenesis was assessed, before and after culture, by classical cytology, by fluorescence in-situ hybridization and by immunocytochemistry with a germline-specific marker. The proportion of cases of maturation arrest at the primary spermatocyte, secondary spermatocyte and spermatid stage in which in-vitro resumption of meiosis was achieved was 24.3% (9/37), 100% (3/3) and 51.1% (23/45) respectively. Serum FSH concentrations were higher than normal in most cases. However, lower values were measured in patients in whom in-vitro spermatogenesis was achieved compared with those in whom no progression was detected. These data show that, under the conditions of this study, germ cells from men with very high serum FSH concentrations (>20 IU/l) are less likely to resume spermatogenesis in vitro than those coming from men with only moderate increase (10-20 IU/l).

Adult↗
PubMed2000

In-vitro differentiation of germ cells from frozen testicular biopsy specimens.

In some men with germ cell maturation arrest, spermatogenesis can be resumed during in-vitro culture of testicular biopsy samples. In this study, we examined whether similar differentiation events can be induced in cultured germ cells from cryopreserved testicular biopsy specimens. Fresh and cryopreserved aliquots of the same testicular biopsy samples were cultured in medium supplemented with FSH and testosterone. After 24 and 48 h of culture, the progression of spermatogenesis and the percentage of Sertoli cells with DNA damage, detected by terminal deoxynucleotidyl transferase-mediated dUTP nick-end labelling (TUNEL), were evaluated. Spermatogenesis progressed in a similar way in fresh and cryopreserved aliquots over the first 24 h of culture. However, in contrast to fresh aliquots, no additional progress of spermatogenesis was detected between the 24 and 48 h time points. The percentage of TUNEL-positive Sertoli cells in fresh aliquots showed only a moderate increase after 24 h of culture, whereas most Sertoli cells from cryopreserved aliquots became TUNEL-positive during the same culture period. These data show that limited progression of spermatogenesis can be achieved by culturing cryopreserved testicular biopsy specimens for 24 h, but no additional benefit can be expected from prolonging the culture beyond this time point.

Biopsy↗
PubMed2000

The effect of FSH on male germ cell survival and differentiation in vitro is mimicked by pentoxifylline but not insulin.

High concentrations of FSH have been shown to boost in-vitro differentiation of germ cells from men with normal spermatogenesis and from some patients with in-vivo maturation arrest. This study shows that the differentiation-promoting effect of FSH is connected to protection against germ cell apoptosis and that both effects can be mimicked by the intracellular cyclic AMP (cAMP)-elevating drug pentoxifylline. On the other hand, a high concentration of insulin, supposed to act at the insulin-like growth factor I receptor, did not exert any effect either on differentiation or apoptosis of germ cells in vitro. These data show that the in-vitro effects of supraphysiological concentrations of FSH on human spermatogenesis are mediated by the classical FSH signal transduction pathway involving cAMP as a second messenger. Pentoxifylline may thus be useful as an alternative means for intracellular cAMP elevation in men with high circulating FSH concentrations leading to desensitization of the FSH receptor.

Acrosome↗
PubMed1999

Serum antibodies anti-H. pylori and anti-CagA: a comparison between four different assays.

The authors compare efficacy of two ELISA assays (one supplied by DIAMEDIX [Delta Biological s.r.l.], and the other by RADIM [RADIM I]) in detecting total anti-H. pylori antibodies, and of two further ELISA methods (one supplied by EUROSPITAL [Helori CTX IgG] and the other by RADIM [RADIM 2]) in identifying anti-CagA antibodies, using sera from 69 controls (20 adults and 49 children) and from 96 patients, obtained before endoscopy. Seventy-three of the patients had H. pylori infection, while the remaining 23 were H. pylori negative (histology and polymerase chain reaction [PCR]). Fifty-two of the H. pylori positive patients, had cagA-positive strain infection, identified by PCR. The DIAMEDIX assay was found to be more sensitive (92%) than RADIM 1 (79%) in identifying H. pylori positive patients, irrespective of the infecting strain. On the other hand, the DIAMEDIX assay was less specific than RADIM 1 for H. pylori-negative patients (43% vs. 83%). However, when patients already treated for H. pylori infection were excluded from the group of H. pylori-negative patients, the DIAMEDIX assay had a specificity of 89%. In identifying anti-CagA antibodies, the kit supplied by RADIM (RADIM 2) had a sensitivity of 90% and a specificity of 94%, whereas that supplied by EUROSPITAL had a sensitivity of 100% and a specificity of 76%. The performances of the two methods in the identification of anti-CagA antibodies were found to be similar. The authors conclude that, in view of its high sensitivity, the DIAMEDIX assay may be useful in screening for H. pylori infection.

Adolescent↗
PubMed1999

In vitro culture facilitates the selection of healthy spermatids for assisted reproduction.

OBJECTIVE: To evaluate the potential usefulness of in vitro culture of germ cells for distinguishing between healthy and apoptotic spermatids. DESIGN: Prospective study. SETTING: Private assisted reproduction laboratories and a university department. PATIENT(S): Men with secretory azoospermia who were candidates for assisted reproductive treatment. INTERVENTION(S): Testicular biopsy samples were cultured in the presence of FSH and testosterone for 48 hours. Germ cell apoptosis before and after culture was evaluated by terminal deoxyribonucleotidyl transferase-mediated deoxyuridine triphosphate nick-end labeling. MAIN OUTCOME MEASURE(S): The percentage of germ cells at different stages of spermatogenesis that showed apoptosis-related DNA damage. RESULT(S): In fresh samples, high levels of apoptosis were detected at those stages of spermatogenesis at which major developmental blocks occurred, with a maximum at the most advanced stage detected. In contrast, apoptotic cells were considerably less well represented at the most advanced stage after culture. CONCLUSION(S): In addition to the previously described facilitation of spermatid recognition and the progression of cytoplasmic maturation, in vitro culture of germ cells is useful to overcome the danger of inadvertent use of apoptotic spermatids for assisted reproduction.

Apoptosis↗
PubMed1999

[Coronary surgery with minimum access and cardiopulmonary bypass].

From October 1997 to March 1998 we operated on seven patients with minimal incision, cardiopulmonary by-pass with femoral cannulation and antegrade blood cardioplegic arrest using the "endoclamp" (Heartport Inc.). The seven patients with isolated severe lesions of the left anterior descending underwent a left internal thoracic artery graft under direct vision. Three had saphenous vein coronary bypass grafts performed to the diagonal (2) and obtuse marginal branches of the left coronary artery. The median cardiopulmonary bypass duration was 75 minutes (30-230) and the aortic occlusion time was 33 minutes (10-117). No major complications occurred and only two minor ones were noted. The median intensive care unit stay was 2 days (1 to 4) and the total hospital stay was 6.5 days (3 to 13). All the patients are in NYHA FC I, without treatment and a follow up of 3 to 6 months after the surgery. With this method of myocardial revascularization with minimal incision and cardiopulmonary bypass the sternotomy-related complications can be avoided, the intensive care unit and hospital stay can be reduced with better convalescence for the selected patients. We believe that this technique is a valid option for an increasing number of patients.

Adult↗
PubMed1999

Reproductive capacity of spermatozoa from men with testicular failure.

Controversial reports have been published about the influence of sperm source and of the underlying testicular pathology on success rates of intracytoplasmic sperm injection (ICSI). In this controlled study, ICSI treatment cycles with testicular spermatozoa from men with obstructive and non-obstructive azoospermia were compared with ICSI ejaculated sperm cycles with semen parameters < or = 5 x 10(6)/ml and < or = 10% progressive motility. The control cases were matched for female age, rank of trial, female basal follicle-stimulating hormone serum concentrations and close proximity to the study group's procedure. The fertilization, cleavage, pregnancy and abortion rates were similar in matched groups irrespective of the type of azoospermia. However, the implantation rate in the non-obstructive azoospermic patient group was significantly lower than that in the matched ejaculated sperm group (13.4% versus 26%, P = 0.05). On the other hand, no impairment of the implantation rate was observed in the obstructive azoospermic patient group. These data show that testicular pathology has a negative impact on reproductive performance of testicular spermatozoa, resulting in a decreased implantation potential without any apparent effect on fertilization and early preimplantation development.

Abortion, Spontaneous↗
PubMed1999

The probability of abnormal preimplantation development can be predicted by a single static observation on pronuclear stage morphology.

This retrospective study was undertaken to determine whether further developmental progression of two-pronucleated (2PN) zygotes can be predicted by a single, non-invasive examination of pronuclei, with the use of criteria based on the number and distribution of nucleolar precursor bodies in each pronucleus. The normal range of pronuclear variability was defined by analysis of zygotes giving rise to embryos transferred in 100%-implantation cycles (pattern 0). Morphological patterns differing from pattern 0 were classified as patterns 1-5. The frequency of developmental arrest of pattern 0 zygotes was only 8.5% as compared with 31.6, 21.9, 30.0, 20.5 and 24. 1% for patterns 1-5 respectively. Relationships of pronuclear patterns with blastomere multinucleation and cleaving embryo morphology were also noted. Clinical pregnancy was achieved in 22 of 44 (50%) treatment cycles in which at least one pattern 0 embryo was transferred, but only in two of 23 (9%) cycles in which only pattern 1-5 embryos were transferred. These data present new evaluation criteria which can be used to predict the developmental fate of human embryos as early as the pronuclear stage, without requiring repeated observations or an exact timing of pronuclear zygote inspection. Further prospective study is needed for clinical validation of these criteria.

Blastocyst↗
PubMed1999

Assisted reproduction for testicular failure: management of germ cell maturation arrest.

The availability of current, state of the art technology has enabled an efficient treatment in cases of infertility caused by testicular failure in which mature spermatozoa or late elongated spermatids can be recovered from the ejaculate or the testis. In those patients in whom only germ cells at earlier stages of spermatogenesis are present, results of the currently available treatments are still inconsistent and largely unpredictable, although some encouraging developments have been achieved over the past year. These new results suggest that developmental failure after fertilization with immature germ cells is mainly due to germ cell apoptosis and shows that an efficient selection of healthy germ cells can be achieved by in-vitro culture. In some cases, this method also allows premeiotic germ cells to achieve in-vitro transmeiotic maturation and thus enables men with in-vivo premeiotic maturation arrest to father a child.

Apoptosis↗
PubMed1999

Cytokines modulate MIA PaCa 2 and CAPAN-1 adhesion to extracellular matrix proteins.

Variations in cancer cell adhesion to extracellular matrix (ECM) proteins might underlie an enhanced metastatic potential. ECM binding is mediated by cell-adhesion molecules, the membrane expression of which might be influenced by soluble mediators, such as cytokines. The aims of our study were to ascertain whether epidermal growth factor (EGF), transforming growth factor beta1 (TGF-beta1), interleukin 1alpha (IL-1alpha), or interleukin 1beta (IL-1beta) can modify MIA PaCa 2 (pancreatic cancer cell line) and CAPAN-1 (metastatic pancreatic cancer cell line) adhesion to fibronectin, laminin, or type I collagen, and whether these cytokines can shift the membrane expression of the hyaluronic acid receptor (CD44). EGF significantly enhanced MIA PaCa 2, but not CAPAN-1, adhesion to fibronectin, laminin, and type I collagen. TGF-beta1 reduced MIA PaCa 2 adhesion to type I collagen, but enhanced CAPAN-1 adhesion to fibronectin and laminin. IL-1alpha was found to enhance MIA PaCa 2 adhesion to fibronectin, while reducing adhesion to type I collagen, whereas IL-1beta reduced the adhesion to laminin. IL-1alpha enhanced CAPAN-1 adhesion to laminin in a dose-dependent manner; IL-1beta slightly increased the adhesion of these cells to laminin at low dosage, and to type I collagen at high dosage. Both IL-1alpha and IL-1beta reduced CD44 membrane expression of MIA PaCa 2, while TGF-beta1 increased the percentage of CD44-positive CAPAN-1 cells. We suggest that the effects on cell adhesion induced by different cytokines depend on the status of the target pancreatic cancer cell. EGF and, in part, IL-1alpha can favor nonmetastatic pancreatic cancer cell adhesion to ECM, possibly favoring tumor spread. Metastatic cells seem to lose the responsiveness to EGF, while becoming hyperresponsive to IL-1alpha. TGF-beta1 might exert an antidiffusive effect on primary, and a prodiffusive effect on metastatic pancreatic cancer cells. Only IL-1alpha, IL-1beta, and TGF-beta1 seem to influence CD44 membrane expression. All the results presented in this study were obtained in vitro, and in vivo studies are needed to verify whether the studied cytokines can favor or counteract pancreatic cancer spread.

Cell Adhesion↗
PubMed1999

[Hydatidiform mole. A case of hydrothorax, expression of a non-neoplastic complication].

Marked stimulation of the chorionic gonadotropins underlies the frequent finding in the mole of larger ovaries with multiple luteal cysts, identifiable using ultrasound imaging, resembling ovarian hyperstimulation syndrome. The authors report a case of hyadatid pregnancy which presented serious non-neoplastic complications. Laboratory tests showed high values of beta-hCG and GOT/GPT, electrolytic alterations, hypoproteinemia, hypoalbuminemia, associated with conditions of severe dyspnea and tachycardia following hydrothorax diagnosed by X-ray. USG showed hypertrophic placenta containing anechoid lacunar areas and swollen ovaries with multiple luteal cysts. Positive results were achieved by using intensive therapy leading to the restitutio ad integrum of damaged functions. Endocrine hyperactivity of the molar trophoblast, with high levels of beta-hCG was responsible for ovarian hyperstimulation. Important findings for the early diagnosis of hyadatid pregnancy are: beta-hCG assay and ultrasound scan; moreover, an adequate follow-up lasting about 6 months is necessary to evaluate the serial trend of beta-hCG and the disappearance of ovarian luteal cysts.

Adult↗
PubMed1999

[The role of antenatal courses in preventing the onset of altered pelvic statics and urinary incontinence].

BACKGROUND AND AIMS: This study was prompted by the frequent finding of urinary incontinence in peri- and postmenopausal women. In an attempt to reduce this incidence, the authors evaluated the role of antenatal courses as an important preventive and operative means of providing information aimed at preventing the onset of alterations to pelvic statics and urinary incontinence. The clinical data of 40 puerperae, of whom 45% had followed our antenatal course, were examined for this purpose. METHODS: A functional examination of the perineum was made in all subjects on discharge after birth and 6 months later. RESULTS: These findings appear to indicate that antenatal courses play an important role in preventing obstetric perineal complications. CONCLUSIONS: During the courses all women were given useful advice on hygiene and diet, including guidelines for suitable regular exercise, the need to drink about 1 litre of unsweetened liquid daily, a balanced diet and advice regardingf perineal relaxation. Subsequently, all subjects were advised to continue exercising after birth to ensure the correct rehabilitation of the perineal floor and they were also given a sheet containing the different learnt during the antenatal courses. In this way these subjects increased their awareness of the need not to underestimate the early symptoms of urinary incontinence should they occur after birth.

Adult↗
PubMed1999

[Biochemical markers of gastric functioning].

The serum determination of pepsinogen A (PGA) and pepsinogen C (PGC) might indicate gastric mucosal inflammation and atrophy. Body gastric mucosa produces both PGA and PGC, while antral mucosa produces only PGC. Therefore, diseases involving mainly the antrum, such as H. pylori infection, are mainly indicated by the variations in serum PGC than in serum PGA. In agreement, when the antral mucosa is infected by the more virulent cagA positive H. pylori strains, which cause severe inflammation, serum PGC significantly increases. Another indirect indicator of gastric inflammation is polymorphonuclear (PMN) oxidative burst after the stimulation with water extracts from H. pylori culture: this parameter is significantly increased in infected if compared to non-infected subjects. The higher oxidative burst response of peripheral PMN in infected patients, possibly consequent to the release of specific cytokines able to prime PMN towards H. pylori products, is unable to eliminate the infection, but it might concur in damaging the gastric mucosa.

Biomarkers↗
PubMed1998

Treatment of severe male infertility by micromanipulation-assisted fertilization: news and views.

Recent progress in cell micromanipulation has made it possible to achieve fertilization even with highly deficient male gametes, by injecting them directly to oocyte cytoplasm. This technique, known as intracytoplasmic sperm injection (ICSI), has proved efficient in most types of sperm pathology. However, ICSI fails when injected spermatozoa are not capable of supporting the process of oocyte activation or when they carry genetic abnormalities incompatible with normal embryonic development. Abnormalities of oocyte activation and the transmission of genetic anomalies to the progeny are also two major concerns relating to the clinical use of ICSI. The use of micromanipulation-assisted fertilization in cases of male germ cell maturation arrest, namely fertilization by round spermatid injection (ROSI), has brought preliminary clinical results, and the improvement of ROSI clinical efficacy remains a major challenge for future research.

Acrosome Reaction↗