Portland cement used in the construction industry improves its properties when wet. Since most dental materials are used in a moist environment, Portland cement has been developed for use in ...dentistry. The first generation material is mineral trioxide aggregate (MTA), used in surgical procedures, thus in contact with blood. The aim of this study was to compare the setting of MTA in vitro and in vivo in contact with blood by subcutaneous implantation in rats. The tissue reaction to the material was also investigated. ProRoot MTA (Dentsply) was implanted in the subcutaneous tissues of Sprague-Dawley rats in opposite flanks and left in situ for 3 months. Furthermore the material was also stored in physiological solution in vitro. At the end of the incubation time, tissue histology and material characterization were performed. Surface assessment showed the formation of calcium carbonate for both environments. The bismuth was evident in the tissues thus showing heavy element contamination of the animal specimen. The tissue histology showed a chronic inflammatory cell infiltrate associated with the MTA. MTA interacts with the host tissues and causes a chronic inflammatory reaction when implanted subcutaneously. Hydration in vivo proceeds similarly to the in vitro model with some differences particularly in the bismuth oxide leaching patterns.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
Ulcerative colitis (UC) is a form of inflammatory bowel disease (IBD) characterized by damage of large bowel mucosa and frequent extra-intestinal autoimmune comorbidities. The role played in IBD ...pathogenesis by molecular chaperones known to interact with components of the immune system involved in inflammation is unclear. We previously demonstrated that mucosal Hsp60 decreases in UC patients treated with conventional therapies (mesalazine, probiotics), suggesting that this chaperonin could be a reliable biomarker useful for monitoring response to treatment, and that it might play a role in pathogenesis. In the present work we investigated three other heat shock protein/molecular chaperones: Hsp10, Hsp70, and Hsp90. We found that the levels of these proteins are increased in UC patients at the time of diagnosis and decrease after therapy, supporting the notion that these proteins deserve attention in the study of the mechanisms that promote the development and maintenance of IBD, and as biomarkers of this disease (e.g., to monitor response to treatment at the histological level).
In the context of obesity, epigenetic mechanisms regulate cell-specific chromatin plasticity, perpetuating gene expression responses to nutrient excess. MacroH2A1, a variant of histone H2A, emerged ...as a key chromatin regulator sensing small nutrients during cell proliferation and differentiation. Mice genetically ablated for macroH2A1 (knockout (KO)) do not show overt phenotypes under a standard diet. Our objective was to analyse the in vivo role of macroH2A1 in response to nutritional excess.
Twelve-week-old whole-body macroH2A1 KO male mice were given a high-fat diet (60% energy from lard) for 12 weeks until being killed, and examined for glucose and insulin tolerance, and for body fat composition. Energy expenditure was assessed using metabolic cages and by measuring the expression levels of genes involved in thermogenesis in the brown adipose tissue (BAT) or in adipogenesis in the visceral adipose tissue (VAT).
Under a chow diet, macroH2A1 KO mice did not differ from their wild-type (WT) littermates for body weight, and for sensitivity to glucose or insulin. However, KO mice displayed decreased heat production (P<0.05), and enhanced total activity during the night (P<0.01). These activities related to protection against diet-induced obesity in KO mice, which displayed decreased body weight owing to a specific decrease in fat mass (P<0.05), increased tolerance to glucose (P<0.05), and enhanced total activity during the day (P<0.05), compared with WT mice. KO mice displayed increased expression of thermogenic genes (Ucp1, P<0.05; Glut4, P<0.05; Cox4, P<0.01) in BAT and a decreased expression of adipogenic genes (Pparγ, P<0.05; Fabp4, P<0.05; Glut4, P<0.05) in VAT compared with WT mice, indicative of augmented energy expenditure.
Genetic eviction of macroH2A1 confers protection against diet-induced obesity and metabolic derangements in mice. Inhibition of macroH2A1 might be a helpful strategy for epigenetic therapy of obesity.
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DOBA, EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, IZUM, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UILJ, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
In this work we analysed, by immunohistochemistry, a series of brain tumors to detect the levels and cellular distribution of Hsp60 and Hsp70. We found that Hsp60 levels were significantly higher ...than those of Hsp70 in neuroepithelial tumors, while levels of both molecules were not significantly different from each other in meningeal neoplasms. In particular, Hsp60 immunopositivity was present mainly at the cytoplasmic level, while Hsp70 immunopositivity was found both in the cytoplasm and in the nucleus of tumor cells. The levels of these molecules in healthy control cells were always very low. Finally, Hsp60 and Hsp70 levels did not correlate with the different types (WHO grade) of neoplasm. Our results are partially in agreement with previous studies and suggest that Hsp60 is not increased by a passive phenomenon (e.g., due to the stress caused by the peritumor environment on cancer cells) but may be actively implicated in tumor progression, e.g. inhibiting tumor cell death or antitumor immune system response, as already postulated in vitro. We also briefly discuss the most recent publications on the extramitochondrial localization of Hsp60 in tumor cells and its role in tumor progression.
Inflammatory bowel diseases (IBD) are characterized by inflammatory conditions of the intestine. Probiotic bacteria (PB) can have beneficial effects in several gastrointestinal disorders. The ...objectives of this study were: (i) to provide an acute experimental IBD model induced by 2,4,6-trinitrobenzenesulfonic acid (TNBS) in CD-1 mice, and (ii) to assess the preventive effects of Citogenex (Lactobacillus casei and Bifidobacterum lactis) supplementation on intestinal tissues and microbiota. Mice were inoculated intrarectally with saline, ethanol or different TNBS solutions. 1%TNBS induced clinical signs of colitis (P less than 0.01) and histological damage (P less than 0.01). Based on these results, mice were pre-treated with Citogenex or saline for 1, 2 or 3 weeks before 1%TNBS treatment. Probiotic pre-treatment determined a reduction of clinical signs (P less than 0.05), histological alterations of colitis (P less than 0.05) and increased beneficial bacteria (P less than 0.05). This study confirms that TNBS-induced colitis in CD-1 mice is useful for studying the mechanisms involved in IBD pathogenesis, and pre-treatment with Citogenex prevents the intestinal damage induced by TNBS.
The concept of a stem cell subpopulation as understood from normal epithelial tissue or bone marrow function has been extended to our understanding of cancer tissue and is now the target of treatment ...efforts specifically directed to this subpopulation. In glioblastoma, as well as in other cancers, increased expression of aldehyde dehydrogenase (ALDH) has been found localized within a minority sub-population of tumor cells which demonstrate stem cell properties. A separate body of research associated increased expression of heat-shock protein-90 (HSP90) with stem cell attributes. We present here results from our initial immunohistochemistry study of human glioblastoma biopsy tissue where both ALDH and HSP90 tended to be co-expressed in high amounts in the same minority of cells. Since 12% of all cells in the six biopsies studied were ALDH positive and 17% were HSP90 positive, by chance alone 2% would have been expected to be positive for both. In fact 7% of all cells simultaneously expressed both markers-a significant difference (p = 0.037). That two previously identified proteins associated with stem cell attributes tend to be co-expressed in the same individual glioblastoma cells might have clinical utility. Disulfiram, used to treat alcoholism for half-a century now, is a potent ALDH inhibitor and the old anti-viral drug ritonavir inhibits HSP90. These should be explored for the potential to retard aspects of glioblastoma stem cells' function subserved by ALDH and HSP90.
► Aldehyde dehydrogenase activity and expression of HSP90 are stem cell markers. ► In human glioblastoma biopsies 7% of cells express both markers. ► Several currently marketed drugs inhibit aldehyde dehydrogenase and HSP90.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
: Background/Aim: Liver steatosis (LS) has been variably associated with chronic hepatitis C (CHC) but whether it affects sustained virological response to antiviral treatment and by what mechanisms ...is a question still under debate, at least for some genotypes. The aim of this work was to assess the frequency of LS, its relationship with host and viral factors and to what extent it can influence the response to antiviral combination therapy with pegylated interferon (INF)+ribavirin in a group of patients with CHC from a single center.
Patients: One hundred and twelve patients with histologically proven CHC were treated with Peg INF‐α 2a 180 μg a week subcutaneously for 48 weeks plus ribavirin 1000 or 1200 mg/day, according to the patient's body weight. Steatosis was graded according to Brunt et al.
Results: Forty‐six out of 112 patients (41.1%) were sustained virological responders (SVR). Seventy‐two out of 112 (64.3%) presented with LS at histology; in this group, there were 24 patients (33.3%) with SVR compared with 22 (55%) of the non‐steatosis group (χ2=6.5, P<0.02). Variables associated with the steatosis group were: higher serum levels of AST (P<0.04), alanine aminotransferase (P<0.02), γ‐GT (P<0.004), genotype 3a (P<0.03) and severity of histology (staging P<0.05) but at multiple linear regression analysis only genotype 3a and staging were significantly associated with LS. In the SVR group, age and body mass index (BMI) were significantly lower (P<0001 and P<0.03, respectively) compared with non‐responders; moreover, genotype 1 was more frequent in the NR group, while genotype 3 was more frequent in the SVR group. At histology, grading and staging were also lower in the SVR group. Multiple logistic regression showed that only the grade of steatosis and genotype 3a were the variables independently associated with SVR.
Conclusions: This study showed a frequency of LS on the higher side of the range so far reported in the literature and confirmed that it negatively influences response to therapy. Genotype1 was confirmed to be the most frequent type in our area. It is more frequent in patients with mild–moderate steatosis and seems to condition therapeutic response negatively, together with BMI and age. In contrast, genotype 3a is more frequent in patients with severe steatosis, but is a favorable predictor of successful therapy.
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BFBNIB, DOBA, FZAB, GIS, IJS, IZUM, KILJ, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBMB, UILJ, UKNU, UL, UM, UPUK
Probiotics (PB) are living microorganisms that act as a commensal population in normal intestines and confer numerous beneficial effects on the host. The introduction of probiotics in the treatment ...of inflammatory bowel disease (IBD) prolongs remission. The aim of this study was to investigate the intestinal and hepatic effects of PB supplementation in an experimental IBD model in mice induced by 2,4,6-trinitrobenzene sulfonic acid (TNBS). In the first step of the experimental procedure, CD-1 male mice, 5 to 6 weeks old, were randomly divided into 3 groups and inoculated intrarectally with, respectively, saline, alcohol, or TNBS to assess the experimental IBD model. In the second step, mice treated, or not, with TNBS inoculation, were treated with PB (Lactobacillus Casei, Bifidobacterum Lactis) for 1, 2 or 3 weeks, on a daily basis. Large bowel (colon and rectum) and liver were processed for histological alterations, according to a scoring system. Large bowel was also assessed for apoptosis by TUNEL assay. TNBS induced, as expected, severe damage and inflammation in the large bowel, including nuclear alterations and apoptosis, and, to a lesser extent, to the liver. Administration of PB determined significant reduction of both histological alterations and apoptosis. PB administration in advance protects from inflammation. In conclusion, supplementation with Lactobacillus casei, Bifidobacterum lactis PB is able to ameliorate the colitis by reversing the histological changes caused by TNBS in mice. Experimentation in human subjects in needed to prove their efficacy in reducing histological alterations that may be present in subjects with IBD.
Hsp60, a mitochondrial chaperonin highly conserved during evolution, has been found elevated in the cytosol of cancer cells, both in vivo and in vitro, but its role in determining apoptosis during ...oxidative stress (OS) has not yet been fully elucidated. The aim of the present work was to study the effects of OS on Hsp60 levels and its interactions with procaspase- 3 (p-C3) and p53 in tumor cells. NCI-H292 (mucoepidermoid carcinoma) cells were exposed to various concentrations of hydrogen peroxide (H2O2) for 24 hours. Cell viability was determined by Trypan blue and MTT assays. DNA damage was assessed by the Comet assay, and apoptosis was measured by the AnnexinV cytofluorimetric test. Exposure to increasing concentrations of H2O2 resulted in a reduction of cell viability, DNA damage, and early apoptotic phenomena. Hsp60, p-C3, p53, and p21 were assessed by Western blotting and immunocytochemistry before and after OS. Hsp60 and p-C3 were present before and after OS induction. Immunoprecipitation experiments showed an Hsp60/p-C3 complex before OS that persisted after it, while an Hsp60/p53 complex was not detected in either condition. The presence of wild type (wt) p53 was confirmed by RT-PCR, and p21 detection suggested p53 activation after OS. We postulate that, although OS may induce early apoptosis in NCI-H292 cells, Hsp60 exerts an anti-apoptotic effect in these cells and, by extension, it may do so in other cancer cells.
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