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G Spera

Publications and source records attributed to G Spera.

At least 37 records · Page 2Linked to original sources
PubMed2003

Natural specific radioactivity in different soils. Transfer in the soil plant food chain.

In order to warrant customer's health we must pay attention to the quality of the environment and production processes; that means look all over alimentary chain. Media speak often about this topics, because of the interest of the public opinion regarding agribusiness; Nether the less much is know about soil radioactivity, but often scant attention is directed to the knowledge of the amount what remains in food and arrives to the man who is the last and main user of the product. As a consequence of that, we have done some originals studies concerning specific radioactivity in alimentary chain: soil-plant-food. These studies have been made in relation with geopedologic position of fields in volcanic, clayey, sandy soils of Latium. We have measured radioactive activity over some alimentary chains both annual (like turnip and garden cress) and pluriannual (such as vine). We made comparisons on the same soils studying the following natural markers: K40, Pb214, and Bi214; and Cs137, one of the main natural markers.

Food Chain↗
PubMed2003

Organic viticulture: efficacy evaluation of different fungicides against Plasmopara viticola.

The restriction on the use of copper salt fixed by the European Community (Reg. EC n. 473/2002) owing to the environment problems due to the copper accumulation in the soil, has stimulated the research to evaluate the possibility to reduce the copper use. This field experiment was carried out to estimate, in an organic vineyard, the effectiveness, against Plasmopara viticola (Berk. et Curt) Berl. et De Toni, of copper compounds at a low rate or alternative copper products. Guideline EPPO/OEPP PP 1/3 (2) has been used. Plots of 18 plants each, repeated 4 times in a randomized design, have been arranged. The obtained results, even if related to circumscribed and extremely favorable field for the development of the grapevine downy mildew, evidenced the impossibility to practice a defense to fixed cadence, succeeding, at the same time, to respect the limits of European Community for copper metal. The reference product, that has guaranteed the best results, determined a total contribution of copper metal of 25.7 Kg/ha that leaves very little possibilities of copper use in the following years, like previewed from the Reg. EC n. 473/2002; therefore a strategy of defense of this type turns out as not usable. The two cupric products characterized by the low metallic content were not completely satisfactory in our operating conditions with high pressure of grapevine downy mildew, but they determined a contribution of copper metal under the limits established by the European Community. Therefore new experiments, using differentiated strategies, should be carried out to improve the effectiveness of these fungicides. About biofungicide, it gave total absence of biological activity against P. viticola. The limits of the used formulations regarding the operating protocol applied, are evidenced, for some of them, by epidemiological results, for the others by the high amount of distributed copper, that causes an accumulation of residual in soil and leaves. Through the examination of the results and considering the particular climatic condition that characterized 2002, we can conclude that the trial must be considerate valid for the stressful situations that affected the vineyard.

Copper↗
PubMed2003

Presence of plant protection products in three agricultural areas of Regione Lazio.

Aim of the research was to verify the impact of plant protection products on three significant agricultural areas of Regione Lazio: Maccarese, Cisterna di Latina, Sabaudia-Terracina. This research studied the presence of some active ingredients, indicated by technicians as distributed, on soil, water, crop and air samples, the last one in greenhouse; the analysis, carried out by multi-residue methods, allowed to investigate also on a large amount of active ingredients not indicated by technicians. The determinations have been obtained, using internal standards, by GC-NPD, GC-ECD, HPLC-UV, HPLC-DAD, with different columns, conditions and wavelength of adsorption. Taking into account the results we could to assert that only a small part of the molecules searched were found in the samples and that they are typical for the crops and the environment treated. In greenhouse, more persistence was founded in wood greenhouse, treated from the outside, probably for the release of a.i. in time from wood and for a better distribution. The active ingredients more frequently founded must be controlled to avoid possible accumulation or leaching, especially for herbicides in the areas of Maccarese and Cisterna di Latina. Furthermore, the molecule on which more attention must be done when applied, are: linuron on carrots, penconazole on zucchini and cymoxanil, often used inappropriately, particularly on minor crops, like red-radish. Although the number of sampling was limited, it has been possible to outline the situation in the three zones considered, for directing choices, that could be more sensible at sanitary spin-off and at the environment.

Air Pollutants↗
PubMed2002

The selective estrogen receptor modulator raloxifene regulates osteoclast and osteoblast activity in vitro.

Raloxifene is a selective estrogen receptor modulator (SERM) that prevents bone loss. Although it is largely used for the treatment of osteoporosis, the mechanisms by which this compound modulates the activity of bone cells are still poorly understood. In this study we investigate whether raloxifene affects osteoclast and osteoblast activity in vitro. Bone marrow cultures were established from neonatal mice and treated with 1,25(OH)(2) vitamin D(3) (VitD(3), 10(-8) mol/L) to induce osteoclast generation. Similar to 17beta-estradiol, raloxifene significantly reduced the number of osteoclasts in a concentration-dependent manner, with maximal inhibition at 10(-11) mol/L (-48%). However, as for 17beta-estradiol, at a high concentration (10(-7) mol/L), the inhibitory effect of raloxifene was abolished. In a pit assay, raloxifene inhibited bone resorption. A maximal effect was observed at 10(-9) mol/L, and maintained at a high concentration, indicating that inhibition of osteoclast formation and inhibition of bone resorption may be due to activation of, at least in part, different pathways. Osteoblasts from neonatal mice calvariae were also exposed to raloxifene. In these cells, this compound induced a concentration-dependent increase of proliferation, which was blocked by the estrogen-receptor antagonist ICI 164,384. Raloxifene also increased the osteoblast-specific transcription factor Cbfa1/Runx2 and alpha2 procollagen type I chain mRNAs, with a pattern that only partially coincided with that of 17beta-estradiol. Consistent with decreased osteoclastogenesis, raloxifene inhibited the mRNA expression of interleukin (IL)-1beta and IL-6 at a low concentration, but not at a high concentration, whereas 17beta-estradiol had similar effects on IL-6 and inhibited IL-1beta at both concentrations. Furthermore, both compounds were able to inhibit tumor necrosis factor (TNF)-alpha-induced IL-1beta, but not IL-6, increase. In conclusion, these data show that raloxifene negatively modulates osteoclasts, and positively affects osteoblasts, suggesting not only an antiresorptive role, but also an osteoblast stimulatory role.

Animals↗
PubMed2001

Sulphasalazine and 5-aminosalicylic acid in long-term treatment of ulcerative colitis: report on tolerance and side-effects.

BACKGROUND: Use of sulphasalazine in ulcerative colitis patients is hampered by a variety of side-effects, including male infertility. 5-aminosalicylic acid is better tolerated and has been increasingly used to treat patients intolerant/allergic to sulphasalazine but it may also be associated with side-effects. AIM: To evaluate tolerance of long-term treatment with sulphasalazine and 5-aminosalicylic acid in ulcerative colitis. METHODS: Side-effects to sulphasalazine (2-3 g/day) and 5-aminosalicylic acid (1.2-2.4 g/day) were recorded in 685 patients: 410 patients received only sulphasalazine, 130 only 5-aminosalicylic acid, and 145 both drugs. In patients with side-effects to sulphasalazine, a desensitisation protocol (rechallenge) was attempted to improve tolerance, and patients still presenting side-effects after desensitisation were switched to 5-aminosalicylic acid. Male fertility was also assessed in 42 males on sulphasalazine and on 5-aminosalicylic acid. RESULTS: Side-effects were observed in 110/555 patients (20%) on sulphasalazine and in 18/275 patients (6.5%) on 5-aminosalicylic acid during a median period of follow-up of 7 and 5 years, respectively. Desensitisation was achieved in 40% of patients intolerant to sulphasalazine. 5-aminosalicylic acid intake induced side-effects in 2/130 patients (1.5%) who had not taken sulphasalazine before versus 4/91 patients (4%) tolerating sulphasalazine and 12/54 patients (22%) intolerant/allergic to sulphasalazine, the difference in incidence of side-effects in the two latter groups being statistically significant (4.4% vs 20.8%, p=0. 001). Fertility was found to be affected in all patients on sulphasalazine but improved when put onto 5-aminosalicylic acid. CONCLUSIONS: 5-aminosalicylic acid should be considered the drug of choice in the treatment of ulcerative colitis bearing in mind that intolerance or allergy may occur in a few patients also on this drug.

Adolescent↗
PubMed2001

Patency of anastomoses after bilio-intestinal bypass: radioisotope demonstration.

BACKGROUND: Bilio-intestinal bypass (BIB) is effective for the treatment of refractory obesity. BIB permits bile flow into the non-functional jejunum, whereas food transit occurs via the remaining intestine. We used the radioisotope method of 99mTc-Hida cholescintigraphy (HC) in the follow-up of patients. METHODS: 21 patients were studied 3 months to 3 years after BIB with HC. After 3 hours acquisition, images were reviewed by two independent observers. Regions of interest (ROIs) were drawn on images: liver parenchyma, cholecysto-jejunal anastomosis (CC), choledochus (COL). Radioactivity taken up by liver was compared with radioactivity of CC and COL. % radioactivity passing through CC (%CC) and through COL (%COL) were determined. The final parameter, -COL, indicates the radioactive bile which does not pass through the choledochus. RESULTS: Anastomoses were found patent a few months to 3 years after operation. -COL showed linear correlation with the decrease in cholesterolemia and in body weight in the 1st year after BIB. CONCLUSIONS: HC shows passage of radioactive bile through anastomoses and provides semiquantitative evaluation of bile flux diversion. Bile flux towards the gallbladder and non-functional jejunal limb far exceeds flux directed towards the duodenum via the choledochus.

Adult↗
PubMed2000

Leydig cell loss and spermatogenic arrest in platelet-derived growth factor (PDGF)-A-deficient mice.

Platelet-derived growth factor (PDGF)- A-deficient male mice were found to develop progressive reduction of testicular size, Leydig cells loss, and spermatogenic arrest. In normal mice, the PDGF-A and PDGF-Ralpha expression pattern showed positive cells in the seminiferous epithelium and in interstitial mesenchymal cells, respectively. The testicular defects seen in PDGF-A-/- mice, combined with the normal developmental expression of PDGF-A and PDGF-Ralpha, indicate that through an epithelial-mesenchymal signaling, the PDGF-A gene is essential for the development of the Leydig cell lineage. These findings suggest that PDGF-A may play a role in the cascade of genes involved in male gonad differentiation. The Leydig cell loss and the spermatogenic impairment in the mutant mice are reminiscent of cases of testicular failure in man.

Animals↗
PubMed2000

Transient estrogen exposure of female mice during early development permanently affects osteoclastogenesis in adulthood.

Estrogens modulate bone tissue turnover in both experimental animal models and postmenopausal women. Our previous studies have shown that exposure to diethylstilbestrol (DES) during the perinatal period increases peak bone mass in female mice in adulthood. We investigated whether developmental DES exposure can influence bone mass by affecting osteoclastogenesis. Female mice were injected with 100 microg/kg body weight DES from days 9-16 of gestation or, alternatively, pups received neonatal injections of 2 microg of DES from days 1-5 of life. Animals were weaned at 21 days of age and effects of estrogen on bone cells were evaluated in adulthood. A significant increase in bone mass in female mice was already observed at 2 months, with a maximal effect in older animals. Bone sections from DES-treated animals showed a significant decrease in osteoclast number and tartrate-resistant acid phosphatase (TRAP) enzymatic activity as compared with controls. To verify the importance of the estrogen surge at puberty in this event, a group of control and DES-treated mice were ovariectomized at 17 days to prevent puberty, and potential effect on osteoclastic cells was evaluated in adulthood. As expected, ovariectomy induced an increase of TRAP-positive cells. DES treatment blunted the ovariectomized-dependent increase of the total number of osteoclastic cells, suggesting a role of developmental DES exposure in the process of bone-cell imprinting. Our data indicate, for the first time, that transient changes in estrogen levels during development modulate bone turnover and osteoclastogenesis likely participating in bone-cell imprinting during early phases of bone development, and that this effect could be induced by direct alteration of bone microenvironment.

Animals↗
PubMed1998

Analysis of Yq microdeletions in infertile males by PCR and DNA hybridization techniques.

Defects in spermatogenesis have been found associated with deletions of different portions of Y chromosome long arm (Yq), suggesting the presence of the azoospermia factor in the control of spermatogenesis. We studied 67 men with idiopathic azoospermia and severe oligozoospermia, cytogenetically normal, for the presence of microdeletions on Yq chromosome. By using polymerase chain reaction (PCR) and Southern blotting techniques we analysed the AZFa, AZFb and AZFc loci on Yq, where deletions have been associated with defects in spermatogenesis. Deletions of a portion of the Y chromosome were detected in five patients. Four of these patients shared deletions in distal Yq11 interval 6, including the DAZ gene, while one patient lacked loci in the proximal Yq11. Testicular histology of two patients bearing distal Yq11 deletions showed two different spermatogenic defects including Sertoli cell-only (SCO) syndrome and maturation arrest, while the patient with microdeletions in the proximal Yq11 showed a SCO phenotype.

Blotting, Southern↗
PubMed1997

Growth hormone and insulin-like growth factor I responses to moderate submaximal acute physical exercise in man: effects of octreotide, a somatostatin analogue, administration.

We evaluated growth hormone (GH) and insulin-like growth factor I (IGF-I) response to moderate submaximal acute short-term physical exercise under basal conditions and after the administration of octreotide, a somatostatin analogue (SA), in a double-blind, counter-balanced experimental protocol. Seven untrained male volunteers performed two identical exercise tests, each on a treadmill (2.5% slope) for 30 minutes (min) at 60% of VO2max. Before starting the exercise test all the subjects received a single administration of placebo or octreotide and vice versa at two different sessions. Plasma GH, IGF-I and lactate assays were evaluated before starting, during, at the end and in the recovery phase. In the placebo-treated group GH rose significantly both during exercise and recovery whereas no significant modifications in IGF-I levels were observed. SA administration inhibited the exercise-dependent GH secretion, which showed a small rise only during exercise and returned to basal levels during recovery. In the same group, IGF-I decreased significantly after exercise compared to basal values. The results suggest that 1) in our experimental conditions acute physical exercise at aerobic threshold does not modify IGF-I concentration 2) SA is able to inhibit the exercise-dependent GH secretion and to decrease post-exercise IGF-I concentration.

Adult↗
PubMed1997

Cervical intraepithelial neoplasia and bacterial vaginosis: correlation or risk factor?

Bacterial Vaginosis (B.V.) is a syndrome defined microbiologically where lactobacilli-dominated flora is exchanged with an abundant complex flora dominated by strict and facultative anaerobic bacteria, constituted by gardenerella, micrococci, streptococci and staphylocci. It has been suggested that B.V. could be important in the development of cervical intracpithelial neoplasias, because the abnormal micro flora can produce careinogenic nitrosamines. The aim of this investigation was to evaluate the correlation between CIN and B.V. in 1,008 patients (median age: 28 years, range 17-60) who were divided into two groups: the first group consisted of 504 patients affected by CIN of different degrees, the second of 504 patients without CIN. All patients were submitted to colposcopy, pap-tests, cytology of the cervical canal and microcolpohysteroscopy in the case of lesions invading the cervical canal. The diagnosis of B.V. is based on four criteria: presence of clue cells, pH 4.5, positive amine test and increased vaginal discharge. X2 Pearson analysis was applied for statistical evaluation of the data. Among the 504 patients in the first group (women affected by CIN of different degrees), 180/504 (36%) women presented B.V. Among the second group (504 women without CIN), 248/504 (49%) women presented B.V. The results of our study demonstrate that there is no significant correlation between CIN and B.V. In the first group of patients affected by CIN and B.V., B.V. was present in 36% of the cases, while in the second group of patients not affected by CIN. B.V. was present in 49% of the cases (P < 0.00005).

Adolescent↗
PubMed1997

Prevention of thromboembolic complications in women undergoing gynecologic surgery.

Our objective was to identify those patients particularly at risk of deep vein thrombosis (DVT) before they underwent extensive gynecologic surgery and to control if, a correct diagnostic analysis and a right pre-operative prophylaxis of patients with risk of developing DVT, was enough to improve post-operative prognosis. Of 2704 patients undergoing gynaecological surgery, 74 were pre-operatively considered at risk of developing DVT. Seventy percent of the patients received pre- and postoperative heparin, while 28% of the women received only postoperative heparin. Nonetheless, seven women receiving this prophylaxis developed DVT. The final results of our study demonstrate that there is a close correlation between incidence of DVT and the presence of risk factors. This incidence can be reduced by prophylactic measures such as elastic stockings for the lower legs, early post-operatory mobilization, hematocrit and volemy control, ending with pharmacological therapy with heparin.

Fallopian Tubes↗
PubMed1997

Hysterectomy in women with cervical pregnancy complicated by life-threatening bleeding: a case report.

A 27-year-old women, gravida 2, para 1 presented with massive vaginal bleeding. After two days of bleeding from the external cervical ostium, intracervical tamponade was performed but the bleeding did not stop. At laparotomy, abdominal hysterectomy with adnexa preservation was done because of malacia tissue and life-threatening hemorrhage. Pathological examination revealed an isthmic pregnancy, gravidic decidua, and chorion villi.

Adult↗
PubMed1995

Testicular development involves the spatiotemporal control of PDGFs and PDGF receptors gene expression and action.

Platelet-derived growth factors (PDGFs) are growth-regulatory molecules that stimulate chemotaxis, proliferation and metabolism primarily of cells of mesenchymal origin. In this study, we found high levels of PDGFs and PDGFs receptors (PDGFRs) mRNAs, and specific immunostaining for the corresponding proteins in the rat testis. PDGFs and PDGFRs expression was shown to be developmentally regulated and tissue specific. Expression of PDGFs and PDGFRs genes was observed in whole testis RNA 2 d before birth, increased through postnatal day 5 and fell to low levels in adult. The predominant cell population expressing transcripts of the PDGFs and PDGFRs genes during prenatal and early postnatal periods were Sertoli cells and peritubular myoid cells (PMC) or their precursors, respectively, while in adult animals PDGFs and PDGFRs were confined in Leydig cells. We also found that early postnatal Sertoli cells produce PDGF-like substances and that this production is inhibited dose dependently by follicle-stimulating hormone (FSH). The expression of PDGFRs by PMC and of PDGFs by Sertoli cells corresponds in temporal sequence to the developmental period of PMC proliferation and migration from the interstitium to the peritubulum. Moreover, we observed that all the PDGF isoforms and the medium conditioned by early postnatal Sertoli cells show a strong chemotactic activity for PMC which is inhibited by anti-PDGF antibodies. These data indicate that, through the spatiotemporal pattern of PDGF ligands and receptors expression, PDGF may play a role in testicular development and homeostasis.

Animals↗
PubMed1995

Pachydermoperiostosis: study of epidermal growth factor and steroid receptors.

Pachydermoperiostosis is a rare osteo-cutaneous disease characterized by hypertrophy of bones and surrounding soft tissues. The cutaneous manifestations include coarsening of facial features, cutis verticis gyrata, digital clubbing, hyperhidrosis and seborrhoea. The pathogenetic mechanism of the disease is still debated, and proposed aetiological factors include genetic influences, anomalies in fibroblast activity, or alteration in peripheral blood flow. We studied a patient with the incomplete form of pachydermoperiostosis, assessing epidermal growth factor receptor (EGF-R) and sex hormone steroid receptors (SR) in the affected skin, and also evaluating the urinary excretion of EGF. The results showed high levels of nuclear steroid receptors, increased cytosolic oestrogen receptors, and no detectable progesterone and androgen cytosolic receptors. EGF-R was also undetectable, and the urinary excretion of EGF was elevated. These findings suggest that the increased tissue sensitivity to circulating sex-steroids could induce enhanced tissue EGF/transforming growth factor alpha (TGF-alpha) production and utilization. The SR-EGF-R system could therefore be involved in determining hypertrophy of the affected tissues.

Adult↗
PubMed1994

Obstetrical implications in multiple pregnancies.

In the present study 90 multiple pregnancies were examined. These were subdivided on the basis of the number of embryos involved (74 twins, 10 triplets, 6 quintuplets) and on whether they were followed at our clinic for the entire pregnancy or not. In each group we analysed certain variables, calculating the respective mean values and standard deviations. We used the ANOVA test to discriminate the eventual differences in the means of the variables analysed, operating a p < 0.05 significance value. In addition, significant differences were analysed by the test of Contrasts (Scheffe F-test). The concept that emerged from the data investigated is that careful management of these pregnancies, carried out in high-level structures, can reduce the incidence of complications on both the maternal and fetal side and thus prevent "minimal brain damage" in the newborn.

Abortion, Spontaneous↗