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101.
102.

Background

Gliadins are involved in gluten-related disorders and are responsible for the alteration of the cellular redox balance. It is not clear if the gliadin-related oxidative stress can induce DNA damage in enterocytes.

Aim

To investigate any possible genotoxicity caused by gliadin and to assess its relationship with oxidative stress in vitro and ex vivo.

Methods

Caco-2 cells were exposed for 6–12–24?h to increasing concentrations (250?μg/mL–1000?μg/mL) of digested gliadin. We investigated: cytotoxicity, oxidative balance (reactive oxygen species, ROS), DNA damage (comet assay and γ-H2AX detection), transglutaminase type 2 (TG2) activity and annexin V expression. H2AX and 8-OHG immunohistochemistry has been evaluated on duodenal biopsies of celiac subjects and controls.

Results

Gliadin induced a significant increase (+50%) of ROS after 12?h of exposition starting with a 500?μg/mL dose of gliadin. Comet assay and γ-H2AX demonstrated DNA damage, evident at the gliadin concentration of 500?μg/mL after 24?h. TG2 activity increased in chromatin and cytoskeleton cellular compartments at different gliadin doses (250/500/1000?μg/mL). The γ-H2AX and 8-OHG immunohistochemistry was altered in the duodenal biopsies of celiac patients.

Conclusions

Gliadin induces cellular oxidative stress, DNA damage and pro-apoptotic stimulation in Caco-2 cells and in the duodenal mucosa of celiac patients.  相似文献   
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105.

Background

Hepatic regeneration requires coordinated signal transduction for efficient restoration of functional liver mass. This study sought to determine changes in lysophosphatidic acid (LPA) and LPA receptor (LPAR) 1–6 expression in regenerating liver following two-thirds partial hepatectomy (PHx).

Methods

Liver tissue and blood were collected from male C57BL/6 mice following PHx. Circulating LPA was measured by enzyme-linked immunosorbent assay (ELISA) and hepatic LPAR mRNA and protein expression were determined.

Results

Circulating LPA increased 72 h after PHx and remained significantly elevated for up to 7 days post-PHx. Analysis of LPAR expression after PHx demonstrated significant increases in LPAR1, LPAR3 and LPAR6 mRNA and protein in a time-dependent manner for up to 7 days post-PHx. Conversely, LPAR2, LPAR4 and LPAR5 mRNA were barely detected in normal liver and did not significantly change after PHx. Changes in LPAR1 expression were confined to non-parenchymal cells following PHx.

Conclusions

Liver regeneration following PHx is associated with significant changes in circulating LPA and hepatic LPAR1, LPAR3 and LPAR6 expression in a time- and cell-dependent manner. Furthermore, changes in LPA–LPAR post-PHx occur after the first round of hepatocyte division is complete.  相似文献   
106.
Pituitary - Along with increased life expectancy and improvements in the diagnostic tools and techniques, the number of elderly patients with symptomatic pituitary tumors being evaluated for...  相似文献   
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108.

Background

Overall survival in hepatocellular carcinoma patients treated with percutaneous radiofrequency ablation is influenced by both recurrence and successive treatments. We investigated post-recurrence survival after radiofrequency ablation.

Methods

Data on 103 early/intermediate patients initially treated with radiofrequency ablation and followed for a median of 78 months (range 68–82) were retrospectively analysed. If intrahepatic disease recurrence occurred within or contiguous to the previously treated area it was defined as local, otherwise as distant; recurrence classified as Barcelona Clinic Liver Cancer stage C was defined by neoplastic portal vein thrombosis or metastases.

Results

A total of 103 patients were included (82.5% male; median age 70 years, range 39–86). During follow-up, 64 recurrences were observed. Median overall survival was 62 months (95% confidence interval: 54–78) and survival rates were 97%, 65% and 52% at 1, 4 and 5 years, respectively. Median post-recurrence survival was 22 months (95% confidence interval: 16–35). Child–Pugh score, performance status, sum of tumour diameters at recurrence and recurrence patterns were independent predictors of post-recurrence survival.

Conclusions

In patients with hepatocellular carcinoma after radiofrequency ablation, clinical and tumour parameters assessed at relapse, in particular the type of recurrence pattern, influence post-recurrence survival.  相似文献   
109.
The aim of this study was to assess the prefrontal cortex (PFC) oxygenation response to a 5-min incremental tilt board balance task (ITBBT) in a semi-immersive virtual reality (VR) environment driven by a depth-sensing camera. It was hypothesized that the PFC would be bilaterally activated in response to the increase of the ITBBT difficulty, given the PFC involvement in the allocation of the attentional resources to maintain postural control. Twenty-two healthy male subjects were asked to use medial–lateral postural sways to maintain their equilibrium on a virtual tilt board (VTB) balancing over a pivot. When the subject was unable to maintain the VTB angle within ±35° the VTB became red (error). An eight-channel fNIRS system was employed for measuring changes in PFC oxygenated-deoxygenated hemoglobin (O2Hb-HHb, respectively). Results revealed that the number of the performed board sways and errors augmented with the increasing of the ITBBT difficulty. A PFC activation was observed with a tendency to plateau for both O2Hb-HHb changes within the last 2 min of the task. A significant main effect of the level of difficulty was found in O2Hb and HHb (p < 0.001). The study has demonstrated that the oxygenation increased over the PFC while the subject was performing an ITBBT in a semi-immersive VR environment. This increase was modulated by the task difficulty, suggesting that the PFC is bilaterally involved in attention-demanding tasks. This task could be considered useful for diagnostic testing and functional neurorehabilitation given its adaptability in elderly and in patients with movement disorders.  相似文献   
110.
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