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B Stefanon

Publications and source records attributed to B Stefanon.

At least 19 recordsLinked to original sources
PubMed2006

Effect of natural antioxidants on superoxide dismutase and glutathione peroxidase mRNA expression in leukocytes from periparturient dairy cows.

During the peripartum period, high-yielding dairy cows experience metabolic stress, which alters their homeostasis and exposes the cows to illness. The aim of this study was to quantify the expression levels of genes involved in antioxidant defences during the transition period in the blood of dairy cows and to evaluate the regulative activity on these genes of natural antioxidants in the diet. Three groups of 7 heifers each, at the 7th month of pregnancy, were used. Starting from 3 weeks before the expected calving date (-22 days), the three groups were allotted to the following experimental treatments: control (CTR, basal diet); lycopene (LYC, basal diet + lycopene 540 mg/day) and grape polyphenols (POL, basal diet + grape polyphenols 10 g/day). Blood was sampled at 22 and 8 days before and 8, 15 and 22 after calving and analysed for the expression level of glutathione peroxidase (GPx) and superoxide dismutase (Cu/ZnSOD) using the real-time PCR technique with LUX (Light Upon eXtension) fluorogenic primers. During the peripartum period (-22 days until + 22 days from calving), Cu/ ZnSOD mRNA expression decreased (p<0.05) in the CTR and LYC groups, but increased at 15 days after calving in the POL group. No significant differences were found in GPx mRNA expression. The results suggest that grape polyphenols may have a controlling effect on peripartum metabolic stress through modulation of superoxide dismutase expression.

Animals↗
PubMed2005

Mammary cell turnover in lactating ewes is modulated by changes of energy fuels.

The study of cell turnover of mammary gland helps to gain understanding of the subtle modulation that largely determines milk production. To evaluate the effect of diet composition on cell turnover of mammary gland, pluriparous sheep were allotted to three experimental groups and fed from day 33 after lambing a control diet (BD), a high starch (HS) diet or a high fat (HF) diet. Biopsies of mammary gland tissue were collected at 50 days after lambing for in situ detection of cell death and RT-PCR analysis of bax, bcl-2, caspase-3 and GST expressions. Both apoptotic and proliferation indexes were significantly higher (P<0.05) in the BD group compared to HS and HF groups. The relative expressions of GST were significantly greater (P<0.05) in HF group compared to the BD and HS groups. There was a significant increase in the ratio of bcl-2 to bax mRNA in the HS and HF groups. Availability of energy substrates for mammary gland can interfere with the cell fate, modulating genes involved in the control of oxidative stress which, in turn, can indirectly regulate cell apoptosis and proliferation.

Animal Nutritional Physiological Phenomena↗
PubMed2004

Detection of apoptosis-inducing factor in involuting mammary tissue by immunoelectron microscopy.

Immunoelectron microscopy was used to study the subcellular localisation of apoptosis-inducing factor (AIF) in involuting bovine mammary tissue. AIF was detected using a polyclonal antibody and secondary anti-rabbit antibody conjugated to colloidal gold particles under optimised conditions. The polyclonal antibody appeared specific for the bovine antigen and immunocytological examination identified specific localisation of AIF in mitochondria, cytoplasm and nucleus of mammary epithelial cells in involuting mammary tissue, suggesting a subcellular translocation in cells undergoing apoptosis.

Animals↗
PubMed2002

Concurrent radiotherapy and weekly paclitaxel for locally advanced or recurrent squamous cell carcinoma of the uterine cervix. A pilot study with intensification of dose.

OBJECTIVE: This study included patients with inoperable primary or recurrent cervical cancer whose treatment plan called for exclusive radiotherapy. The endopoints of the study were to confirm the feasibility of concurrent radiotherapy and paclitaxel in relation to potential acute toxicity and to evaluate if an increase of complete local control might be obtained with the association of paclitaxel to radiotherapy as a radiosensitizer. METHODS: Twenty patients (13 new cases, stage IIB-III, and 7 with pelvic recurrences) were enrolled and, with exclusion of one recurrence, 19 were evaluable for acute toxicity and response. In new cases, radiotherapy was conventionally administered: 50.4 Gy/28 fractions by external beam (whole pelvis) followed by intracavitary cesium or reduced transcutaneous field. In recurrences, radiotherapy was performed with external beam only through individualized fields. Paclitaxel was administered weekly at the dose of 40 mg/m2 or 60 mg/m2 during the entire course of external radiotherapy. RESULTS: Complete regression (CR) as defined by clinical and imaging examinations was achieved in eight of the 13 new cases (62%) and in four of the six recurrences (66%), for a total complete response rate equal to 63%. Five patients (3 treated with 40 mg/m2 and 2 with 60 mg/m2) experienced grade 3 small bowel toxicity, one patient treated with 40 mg/m2 grade 3 bladder toxicity and one patient treated with 60 mg/m2 had grade 4 mucositis. Out of 12 CR patients at the end of treatment, ten maintain complete local remission for a median follow-up of 47 months but two have developed distant metastases. CONCLUSION: The results confirm that this approach is feasible and suggest the use of paclitaxel as radiosensitizer in locally advanced cervical cancer.

Adult↗
PubMed2001

Using artificial neural networks to model the urinary excretion of total and purine derivative nitrogen fractions in cows.

A dataset of 177 individual nitrogen balances from dry and lactating cows was split in two independent groups: training dataset (n = 130) and challenge dataset (n = 47). The training dataset was used to develop multiple linear regressions (MLR) and artificial neural networks (ANN) aimed at predicting the urinary excretion of total (NURI) and that of purine derivative nitrogen (PDN). Input variables for the prediction of NURI were crude protein (CP) intake, effective degradability of non-protein dry matter (DM), neutral detergent fiber (NDF) content of the diet, live weight and milk yield. Live weight, total carbohydrate intake, the ratio of non-protein DM degraded to CP degraded and milk yield corrected for DM intake were entered to predict PDN. The regression between predicted and observed values for the training dataset showed a better statistical accuracy of ANN than did MLR models, especially for PDN. The evaluation of the two models on the challenge dataset showed similar determination coefficients, either when predicting total nitrogen excretion (0.623 and 0.614 for ANN and MLR, respectively) or PDN (0.688 and 0.666, for ANN and MLR, respectively). Moreover, both approaches were affected by a tendency to under-predict both targets at high levels of NURI and PDN. However, with the ANN approach, it is possible to study the response of the model to modifications of individual inputs by the so-called response analysis. This unique feature could be used to study the effect of different physiological situations as well as providing hypotheses for additional research.

Animals↗
PubMed2000

Prognostic indicators in melanoma of the vulva.

BACKGROUND: The aim of this study was to evaluate the prognostic significance of clinical-pathologic variables in melanoma of the vulva. METHODS: From 1979 through 1995, 40 women with a diagnosis of vulvar melanoma underwent radical surgery. Patient age, tumor size and site, histologic type, ulceration, tumor thickness, lymph node status, and number of positive lymph nodes were assessed for prognostic significance by multivariate analysis. RESULTS: Tumor thickness was a significant predictor of lymph node involvement, but not of survival. The most powerful predictors of survival by multivariate analysis were the lymph node status (P = .002) and the number of positive lymph nodes (P = .00003). CONCLUSIONS: The number of positive lymph nodes represents the strongest prognostic factor in melanoma of the vulva. Because of the lack of effective adjuvant therapies, such prognostic indicators might be used to define the timing and extent of the surgical approach.

Adult↗
PubMed2000

Exact Touch: a new device for cervical cytology. Comparison with Ayre spatula plus Cytobrush.

Exact Touch is a new plastic device for the collection of cells from the ectocervix and endocervix. A total of 189 consecutive women were evaluated, 94 with the Ayre/cytobrush and 95 with Exact Touch. Sampling was performed by only one clinician, and the slides were analysed by only one cytotechnologist, who had no information about the sampling method. Our results showed that more endocervical and metaplastic cells were collected by Exact Touch than by Ayre/cytobrush.

Adult↗
PubMed2000

Effect of alpha-tocopherol deprivation on the involution of mammary gland in sheep.

The objective of this study was to investigate the effect of alpha-tocopherol deprivation on mammary gland involution and apoptosis in sheep. Two groups of four single lamb ewes were used. The control group received 100 mg/d of RRR-alpha-tocopherol supplementation and the experimental group received no vitamin E supplementation. After 3 mo of suckling, ewes were dried off, and blood samples from the jugular vein and tissue biopsies from the mammary gland were collected at d 1, 3, 5, and 8 after dry-off. The experimental group had lower plasma concentrations of alpha-tocopherol (1.8 vs. 4.2 micromol/L), lower glutathione peroxidase activity in erythrocytes, and higher concentration of malondialdehyde in plasma than the control group. Immunohistochemical analysis of tissue samples resulted in marked differences of bcl-2 and bax protein expressions during involution and between groups. The bax expression was decreased by alpha-tocopherol deprivation at 1, 3, and 5 d, but not at 8 d, while the bcl-2 score was higher only at 8 d (1.5 vs. 0.0 for experimental and control groups, respectively). As a result, the bcl-2 to bax ratios were increased for the experimental group at 1 and 8 d. During involution, apoptotic counts increased (from 0.12 to 4.06%), but no effects were detected in relation to bcl-2 to bax ratio and alpha-tocopherol. These results indicate that alpha-tocopherol can control bcl-2 expression, but not apoptosis in cells of the mammary gland during involution.

Animals↗
PubMed2000

Malignant melanoma of the vagina. A report of 15 cases.

Twenty patients affected by vaginal malignant melanoma, 15 of which were evaluable for outcome, were observed from 1969 to 1993. Two patients died postoperatively, nine patients developed recurrences and four patients had no disease-free period. All patients died of their disease and the median overall survival was 19 months. The natural history of vaginal malignant melanoma differs from that of the skin with a more aggressive behaviour. Primary treatment should be wide local excision of the tumor.

Adult↗
PubMed1999

Apoptotic cell death, bax and bcl-2 expression during sheep mammary gland involution.

Involution in ovine mammary tissue was studied by light and electron microscopy, and bax and bcl-2 protein distribution was examined by immunohistochemistry from the last day of lactation until the 8th day of drying off. The mammary gland alveoli were examined and the area of glandular epithelium was evaluated morphometrically. Regression of mammary gland epithelium by apoptosis was first identified 2 days after the end of lactation, and increased until day 8. Bax protein was detected throughout this period and was highest on the eighth day. A weak positive reaction for bcl-2 was observed only on days 1 and 8 after cessation of lactation. It is concluded that sheep mammary gland involution involves cell death by apoptosis and that bcl-2 gene family members are involved in the process.

Animals↗
PubMed1999

Long-term results of sequential chemotherapy-radiotherapy-chemotherapy in locally advanced squamous cell carcinoma of the uterine cervix.

PURPOSE OF INVESTIGATION: In order to evaluate the impact of sequential chemotherapy-radiotherapy-chemotherapy on local control and survival, a follow-up study was carried out 12 years after the treatment of 22 patients with FIGO stage IIB-III squamous cell cervical cancer. METHODS: Patients were submitted to three cycles of induction chemotherapy (cisplatin and bleomycin) followed by whole pelvis irradiation and central boost with endocavitary brachytherapy. Ten patients underwent three further cycles of chemotherapy after radiotherapy. All patients were maintained by regular follow-up. Only one patient was lost 48 months after treatment. RESULTS: At the end of treatment complete response was obtained in 14 patients (63.5%). Four of these recurred locally, and one at also distance. Eight patients failed to obtain a complete response. Twelve patients died from disease and one patient died from other causes. Nine of 22 (41%) patients are alive without evidence of disease with a median follow-up of 134 months. Acute toxicity was mild, while two severe late complications were observed. CONCLUSIONS: The achievement of complete remission at the end of treatment is important in terms of life expectancy. Further chemotherapy appears useful for patients who do not reach complete local remission after radiotherapy.

Adult↗
PubMed1998

Laser conization assisted by crypt visualization for cervical intraepithelial neoplasia.

OBJECTIVE: To describe intraoperative visualization of crypts and its effects on specimen clearance, safety, and clinical results of excisional treatment of cervical intraepithelial neoplasia (CIN). METHODS: We treated 147 patients with high-grade CIN (II-III) and colposcopically-assessed endocervical extension, using a CO2 laser instrument in a day-hospital setting. Endocervical walls were stained preoperatively with a 2% methylene blue aqueous solution. Cervical conization was done by laser under colposcopic vision. Stromal incision and cone shape were directed laterally to the endocervical crypts by intraoperative visualization in transparency of the stain. RESULTS: We were able to make stromal incisions at minimal and uniform radial distances from the cervical canal, thus allowing individualized cone shape and optimal bleeding control. Median (range) base diameter and height of specimens were 18 (13-24) and 20 (15-26) mm, respectively. The final histologic diagnosis was CIN II in 35 patients, CIN III in 111, and microinvasive carcinoma in one. Endocervical disease extension was confirmed in 103 patients (70%); the median (range) length of CIN in the 99 evaluable cases was 15.6 (0.5-25.7) mm, and crypt involvement was found in 39 (26.5%). All lateral margins were free of dysplasia. Four specimens (2.7%) had positive apical margins. No significant complications occurred, and fertility did not seem to be impaired. With a median (range) follow-up period of 68 (60-92) months, only 1.4% of patients experienced recurrence; two patients, both with involved crypts, had recurrent dysplasia at 23 and 45 months, respectively. CONCLUSION: Laser microsurgical conization assisted by crypt visualization facilitates safe and complete removal of CIN extending into the endocervix.

Adult↗
PubMed1997

Cytokine production patterns in cervical intraepithelial neoplasia: association with human papillomavirus infection.

BACKGROUND: Genital infection with certain strains of human papillomavirus (HPV) is associated with a high risk of malignant transformation, and HPV-associated cervical intraepithelial neoplasia (CIN) can become invasive cancer. Host factors are critical in regulating tumor growth, and cytokines that modulate immunologic control may be of particular importance. The type 1 cytokines interleukin 2 (IL-2) and interferon gamma (IFN gamma) are immunostimulatory and are thus capable of limiting tumor growth. The type 2 cytokines interleukin 4 (IL-4) and interleukin 10 (IL-10) are immunoinhibitory and are thus capable of stimulating tumor growth. PURPOSE: We analyzed the production of cytokines by peripheral blood mononuclear cells (PBMCs) in women with CIN associated with localized or extensively spread HPV infection. METHODS: Thirty women diagnosed with CIN and 10 age- and sex-matched healthy control subjects were enrolled in the study conducted at Istituto Nazionale Tumori, Milan, Italy. The following parameters were analyzed: 1) HPV infection of the cervix and other sites of the lower genital tract by colposcopic, cytologic, and histologic examinations; 2) HPV typing; 3) in vitro production of IL-2 by PBMCs in response to stimulation with soluble antigen (influenza [FLU] antigen) or to cell-associated human leukocyte antigen (HLA) alloantigen; and 4) in vitro production of the type 1 cytokines IL-2 and IFN gamma and of the type 2 cytokines IL-4 and IL-10 by PBMCs in response to mitogen stimulation. Statistical significance was determined by nonparametric tests (two-sided). RESULTS: High-grade CIN associated with HPV infection was detected in all case patients, and HPV type 16 or 18 infection was detected in cervical tissue of 21 (70%) of 30 case patients. HPV infection that had spread to other sites of the lower genital tract, thus resulting in more extensive disease, was detected in 16 (53%) of the 30 individuals with CIN, whereas HPV infection was limited to the portio in 14 (47%). IL-2 production by PBMCs in response to stimulation with soluble antigen or HLA alloantigen was reduced in the group with extensive disease compared with that in the group with localized disease or with that in healthy control subjects. In contrast, IL-4 and IL-10 production in response to mitogen stimulation was elevated in the group with extensive disease compared with that in the group with localized disease or with that in healthy control subjects. The highest production of IL-4 and IL-10 was detected in patients with HPV infection that had extended beyond the genital tract. CONCLUSIONS: CIN is characterized by different immunologic profiles, in which HPV infection is or is not confined to the portio. Production of cytokines that mainly enhance potentially protective cell-mediated immunity is defective in the women in whom extended HPV infection was observed. A pronounced shift from type 1 to type 2 cytokine production is associated with more extensive HPV infection. IMPLICATIONS: These data reinforce the need for detailed analyses of immune dysregulation in CIN patients. They also suggest the potential usefulness of the cytokine assays for determining prognosis or deciding whether cytokine-based therapy is indicated.

Adult↗
PubMed1996

Ability of mathematical models to predict faecal output with a pulse dose of indigestible marker.

The aim of the work was to compare the faecal output and digestibility estimated by two mathematical approaches with the actual amount of faeces excreted or feed digested by Simmental cows. Experimental data (intakes and digestibility measured over 5 d) and faecal Cr concentrations (measured at 0, 4, 8, 12, 16, 24, 32, 48, 56, 72, 96, 120 and 144 h after a pulse dose of Cr-mordanted forage) were collected from published experiments and fitted to a multicompartmental (MC) model and a gamma age-dependent (AD) model. From a statistical point of view, the MC model was very satisfactory while the AD model produced lower r2 and higher SE values and reached satisfactory statistical values only for higher DM intakes (lactating animals). The MC model produced higher correlations with the digestibility values while the AD model generated better correlations with the intake data; DM intake and digestibilities were more highly correlated with the model's parameters than neutral-detergent fibre terms. The regression between the estimated faecal outputs obtained with the two models showed an intercept close to 0 (P > 0.05) and angular coefficients near 1; there was a good correspondence of the estimates especially for the lowest values of output. The r2 values of the regressions were 0.800 and 0.829 for the MC and AD models respectively and their SE were 2.93 and 2.63. The ability of the two models to predict faecal output and digestibility was very similar, independent of the statistical accuracy of fitting the Cr-concentration data. The results indicate that variation of Cr concentration is the result of the entire digestive process, i.e. dilution and passage, which interact in a competitive or associative way.

Animal Feed↗