Grape pomace improves antioxidant capacity and faecal microflora of lambs.

Grape pomace is a by-product of winemaking process and rich in bioactive compounds such as plant polyphenols having antioxidant and antimicrobial activities. As known, oxidative stress may cause a number of pathological conditions in farm animals and thus affecting animal welfare and production. Moreover, pathogenic bacteria affect animals' health status. Thus, the objective of this study was to investigate whether lambs' feed supplemented with grape pomace enhances the antioxidant mechanisms and reduces the growth of pathogenic bacteria. For this purpose, redox status was assessed in blood and tissues using oxidative stress markers in lambs fed with diet supplemented with grape pomace. Moreover, the effect on bacterial growth was assessed by examining microbial populations in lambs' faecal microflora. The following oxidative stress markers were assessed: reduced glutathione (GSH), catalase activity (CAT), total antioxidant capacity (TAC), thiobarbituric acid-reactive substances (TBARS) and protein carbonyls (CARB). Twenty-four lambs were assigned to two experimental groups receiving standard or experimental diet for 55 days. Blood and tissues (liver, quadriceps muscle, spleen, heart and brain) were collected at two different time-points, 42 and 70 days post-birth, after ration administration. The results showed that lambs fed with experimental diet had significantly increased antioxidants mechanisms in blood and tissues as shown by increases in CAT and GSH compared to control. Moreover, lambs fed with the experimental diet exhibited decreased oxidative stress-induced damage to lipids and proteins as shown by decreases in TBARS and CARB respectively. In addition, the experimental diet enhanced the growth of facultative probiotic bacteria and inhibited the growth of pathogen populations such as Enterobacteriacae and E. coli. This is the first study investigating the effect of diet supplemented with grape pomace on the redox status and microbiota of lambs.

Immunophenotypic analysis of the p53 gene in non-melanoma skin cancer and correlation with apoptosis and cell proliferation.

BACKGROUND: Sunlight precipitates a series of genetic events that lead to the development of skin cancers such as basal cell carcinoma (BCC) and squamous cell carcinoma (SCC). The p53 tumour suppressor gene, which plays a pivotal role in cell division and apoptosis, is frequently found mutated in sunlight-induced skin tumours. OBJECTIVE: To investigate the immunoreactivity of the p53 gene in non-melanoma skin cancers and to correlate its expression with apoptotic and cell proliferation markers. METHODS: We analysed 35 non-melanoma tumours including 19 BCCs and 16 SCCs from sun-exposed skin areas. p53 protein expression was studied immunohistochemically using the DO7 monoclonal antibody against wild-type and mutant p53 forms. The percentage of p53-immunopositive nuclei was measured by image analysis. Cell proliferation and apoptosis were also assessed by image analysis following Ki-67 immunostaining and application of the TUNEL method on paraffin sections, respectively. RESULTS: The percentage of p53-expressing cells varied from 3.5 to 90 in BCCs (median value 54.4%) and from 3.7 to 94 in SCCs (median value 40.3%). The mean value of Ki-67-positive cells was comparable in both groups of tumours with a mean value of 40.6% in BCCs and 34.6% in SCCs. Conversely, the TUNEL assay showed sporadic staining of apoptotic cells within the tumours with a mean value of 1.12% in BCCs and 1.8% in SCCs. p53 protein expression was correlated positively with cell proliferation (r = 0.75, P = 0.000001) and negatively with apoptosis (r = -0.23, P = 0.05). CONCLUSION: p53 immunoreactivity was high in the majority of the skin carcinomas examined and correlated positively with cell proliferation and negatively with apoptosis. The p53 protein overexpression appears to be related to an inactivated protein resulting from mutations of the p53 gene or other unclear molecular mechanisms.

p53, p21 and p27 protein expression in head and neck cancer and their prognostic value.

Histological specimens from 62 laryngeal and 31 oral carcinomas were immunohistochemically assessed for p53, p21 and p27 proteins; cases with > 10% labelled nuclei were considered as positive. p21 showed higher expression in patients > 65-years-old (P = 0.04), in chemotherapy responders (P = 0.02), and in stage III patients with longer overall survival (P = 0.02), representing the only independent prognostic factor in the multivariate analysis. In addition, stage III patients with p53-/p21+ showed the longest survival whereas those with p53+/p21- tumors showed the shortest overall survival (P = 0.02). A significant influence on the survival of stage III patients was also found for the combinations of p21 and p27 proteins with p21+/p27- imparting the best and p21-/p27+ the worst prognosis (P = 0.04). p27 expression was significantly related to oral cancer specimens (P = 0.04) and to moderate and high tumor grade (P = 0.01). p53 expression was not significantly related to any of the examined clinicopathological characteristics. Our findings indicated that, by functionally promoting apoptosis, p21 seems to play a key role in the successful response to chemotherapy and may be considered as a predictive factor of a better prognosis in stage III patients with head and neck cancers.

Molecular cytogenetics of chromosome 11 in pituitary adenomas: a comparison of fluorescence in situ hybridization and DNA ploidy study.

Chromosome 11 abnormalities were detected by fluorescence in situ hybridization (FISH) technique and compared with DNA ploidy in 24 surgically removed pituitary adenomas. The tumors were diagnosed and classified by histology, electron microscopy, and pituitary hormone immunocytochemistry. They included 2 densely granulated somatotroph (DG-SM) and 4 sparsely granulated somatotroph (SG-SM) adenomas, 3 SG lactotroph (LT), 2 mixed somatotroph-lactotroph (SM-LT), 4 functioning corticotroph (CRT), 1 silent CRT subtype 1, 1 thyrotroph, 1 mixed thyrotroph-somatotroph, 2 gonadotrophs, and 4 null cell adenomas. FISH analysis with an alpha-satellite DNA probe specific for chromosome 11 showed numerical abnormalities in 16 functioning (94%) and 5 nonfunctioning (71%) adenomas. Ten functioning tumors showed aneuploid histograms, whereas the remaining and all nonfunctioning adenomas were diploid. Aberrant chromosome 11 signals were noted mostly in aneuploid adenomas involving 17% to 100% of their cell population. The severity of chromosome 11 aberrations in adenomas containing extra copies often correlated with a higher DNA index (DI). Monosomy 11 as dominant aberration was noted in a mixed SM-LT and to a lesser degree in 3 CRT adenomas involving 21% to 97% of their cell population. Two of these CRT adenomas were associated with normal DI, whereas the remaining third showed a high DI, indicating increased copy number of chromosomes other than of chromosome 11. In conclusion, chromosome 11 abnormalities are common in all types of pituitary adenomas, occurring more frequently in functioning tumors. Specific numerical abnormalities, such as monosomy and trisomy, tend to be associated with certain adenoma types, whereas tumors with extra chromosome 11 copies often exhibit aneuploid histograms.

Effect of fixation on interphase cytogenetic analysis by direct fluorescence in situ hybridization on cell imprints.

The direct fluorescent in situ hybridization (FISH) technique using a centromerespecific DNA probe for chromosome 11 was applied on fresh tissue imprints from melanomas and pituitary adenomas. The cell imprints were fixed in acetone and formalin, and the influence of fixation was evaluated. Acetone fixed imprints gave a sharp and intense fluorescent signal in a large number of cells from both tumors without any pretreatment. In contrast, formalin fixed imprints disclosed a weak hybridization signal in a few cells even after careful enzymatic digestion. Direct FISH on acetone fixed cell imprints represents a simple and time saving technique applicable to any laboratory for the study of numerical chromosomal abnormalities.

The Budd-Chiari syndrome in pregnancy.

A case of Budd-Chiari syndrome in a young woman, which started probably in the last trimester of pregnancy, is described. The diagnosis was made clinically and was confirmed by inferior venacavography and on exploratory laparotomy. The possible connection of the syndrome with the pregnancy is discussed.