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1.
BACKGROUND: Oxygen-free radicals generation is considered to be a major cause of gastric injury during reperfusion. Chemiluminescence has been used to assess real-time free radical release on the surface of isolated organs. AIMS: To evaluate the combined use of chemiluminescence and gastroendoscopy techniques and to assess the real-time production of free radicals during ischemic damage of the gastric wall in an animal model. PATIENTS AND METHODS: For the experiment, an optical junction was set up between a fibroendoscope and a luminograph apparatus. Three pigs were submitted to gastrofibroendoscopy before, during and after 30 min of clamping of the coeliac artery. Under basal conditions, at the end of the ischemic phase and at the beginning of reperfusion, 1 mM of lucigenin, a specific superoxide enhancer, was injected in the left gastric artery of the animal. The endoscopic live images and chemiluminescence emission were recorded and successively superimposed to measure rate and spatial distribution of photon emission (photons/s). RESULTS: Free radical production was not observed under basal conditions or during the ischemic phase, but significantly increased during reperfusion reaching a maximum peak after 15 min (0.6+/-0.2 photons x 10(5)/s) and decreased progressively thereafter. The superimposition of live and chemiluminescence images allowed the determination of the regional production rate and distribution of photons. CONCLUSIONS: Preliminary observations, in an animal model, on an innovative imaging system which allows the visualization of rate and spatial distribution of reactive oxygen species formation are presented. This new endoscopic technique could be useful for the assessment of oxidative gastric mucosal injury in several gastric diseases; however, further studies remain necessary to determine the applicability of this technique in humans.  相似文献   
2.
Clericuzio-type poikiloderma with neutropenia is a well-defined nosological entity, but despite a remarkable number of clinical reports, no long term follow-up data has been presented to date regarding patients with this rare condition.Here we describe the results of clinical follow-up of three siblings, one male (Patient 1) and two females (Patients 2 and 3), subsequent to their first clinical and then molecular diagnosis of Clericuzio-type poikiloderma with neutropenia syndrome due to mutation of USB1gene. Patient 1 always expressed the most severe phenotype, while patients 2 and 3 showed an intermediate and mild phenotype, respectively, as observed since their first clinical evaluation. None of the patients developed skin cancer and/or myelodysplastic disorders considering the peripheral haematological findings. Lens opacity, never reported before, was found in two of the three patients.The long term follow-up observations confirm the stability over time of the pronounced intra-familial heterogeneity of clinical manifestations observed prior to and upon molecular diagnosis. We conclude that prolonged follow-up is an adjunct tool to monitor intra-familial variability of PN clinical spectrum which may favour surveillance of more serious complications of the disease among siblings, when a patient-specific clinical expressivity is present.  相似文献   
3.
LCx was compared to other assays in measuring human immunodeficiency virus type 1 (HIV-1) CRF02 viremia. LCx showed significant but low correlation with the other methods. Values of <2.60 log(10) cp/ml were observed in 29.6% of specimens with LCx and in only 14.8% with bDNA and PCR, suggesting suboptimal performance of LCx with CRF02.  相似文献   
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BACKGROUND: H. pylori and age are two known risk factors for atrophic gastritis and high epithelial cell turnover may be an indicator for preneoplastic changes in the stomach. We searched for an association between H. pylori, age and gastritis in the general population together with the proliferative state into the antral mucosa. METHODS: We examined gastric biopsies from antrum and corpus of 117 consecutive volunteers which were endoscoped during a population study in San Marino. H. pylori status was determined by serum IgG antibodies, rapid urease test on biopsies and histology. Presence of gastritis and grading of inflammation, activity, intestinal metaplasia and atrophy were ascertained using Sydney System. On a subsample of 36 subjects without endoscopic lesions we performed an immunohistochemical study on gastric cell proliferation using PCNA. A computer-aided count was made on stained epithelial cells to evaluate labeling index. Statistical analysis was performed using chi 2 test and linear regression. RESULTS: Inflammatory infiltrate (both activity and mononuclear cells), (p < 0.0001) and intestinal metaplasia (p < 0.004) were significantly higher in H. pylori positive subjects. Atrophic gastritis was present in 82% H. pylori positive subjects vs 17.6% (p < 0.0001). Labeling Index was significantly higher in H. pylori positive subjects (p < 0.005) and it was correlated with inflammation and atrophy (p = 0.001). Elderly H. pylori negative subjects have a lower cell turnover (p = 0.006) but H. pylori infected subjects do not show any decrease of Labeling Index with age. CONCLUSIONS: In the general population of an area with high gastric cancer rate, H. pylori infection is associated with atrophic gastritis and with hyperproliferative gastric cell state. These conditions are present either in young and old age and increase the neoplastic risk of gastric mucosa.  相似文献   
6.
Several papers have attempted to find neurological and neuropsychological predictors of progression in Alzheimer's disease (AD) till now. Despite this quite large amount of works, different and not univocal conclusions have been reported in this field. Different study samples, different end-points and differences in statistical methods can explain much of the inconsistency in the results obtained. In our study, AD patients were examined in a very early stage of the disease to avoid any possible risk to examine subjects at different times of evolution. All the patients underwent an extensive neuropsychological test battery twice (baseline and follow-up) spaced out over about 1 year and were divided into two groups of fast decliners (FD) and slow decliners (SD) on the basis of their rate of decay at the MMSE score. Verbal memory tests, mental control abilities and attention-demanding tasks seem to play a pivotal role in distinguishing the two groups of subjects in the early stage of the disease. Moreover, FD patients show a worse performance than SD at the baseline in most of the cognitive domains explored. In conclusion, different subtypes of AD do exist and an important predictor of progression is represented by the severity of the cognitive impairment at the onset.  相似文献   
7.
Despite the high probability of cure of patients with acute promyelocytic leukemia (APL), mechanisms of relapse are still largely unclear. Mutational profiling at diagnosis and/or relapse may help to identify APL patients needing frequent molecular monitoring and early treatment intervention. Using an NGS approach including a 31 myeloid gene-panel, we tested BM samples of 44 APLs at the time of diagnosis, and of 31 at relapse. Mutations in PML and RARA genes were studied using a customized-NGS-RNA panel. Patients relapsing after ATRA-chemotherapy rarely had additional mutations (P = .009). In patients relapsing after ATRA/ATO, the PML gene was a preferential mutation target. We then evaluated the predictive value of mutations at APL diagnosis. A median of two mutations was detectable in 9/11 patients who later relapsed, vs one mutation in 21/33 patients who remained in CCR (P = .0032). This corresponded to a significantly lower risk of relapse in patients with one or less mutations (HR 0.046; 95% CI 0.011-0.197; P < .0001). NGS-analysis at the time of APL diagnosis may inform treatment decisions, including alternative treatments for cases with an unfavorable mutation profile.  相似文献   
8.
AIMS: Patients with heart failure (HF) have elevated values of the pro-inflammatory protein CD40L but the underlying mechanism is unclear. This study was performed to evaluate the interplay between tumour necrosis factor alpha (TNFalpha) and CD40L in HF. METHODS AND RESULTS: In patients with HF (n=86) and healthy subjects (HS, n=43), plasma levels of soluble CD40L (sCD40L), TNFalpha, soluble receptors of TNFalpha such as soluble TNF receptors I and II (sTNFR1 and sTNFR2), and 8OH-dG, a marker of oxidative stress, were determined. Also, an in vitro study was performed by determining platelet CD40L regulation upon platelet stimulation with TNFalpha. Compared with HS, HF patients had higher plasma values of sCD40L, TNFalpha, sTNFR1 and sTNFR2, and higher platelet expression of TNFR1 and TNFR2 with a progressive increase from NYHA I to NYHA IV classification. sCD40L significantly correlated with TNFalpha, sTNFR1, and sTNFR2; plasma levels of TNFalpha significantly correlated with sCD40L. Incubation of platelets from HF patients with a TNFalpha receptor inhibitor significantly decreased platelet CD40L expression. The in vitro study demonstrated that TNFalpha significantly increased CD40L expression, an effect weakly influenced by aspirin but significantly reduced by AACOCF3, an inhibitor of PLA(2), apocynin, an inhibitor of NADPH oxidase, or staurosporine, an inhibitor of PKC. CONCLUSION: The study shows that in HF patients, platelet CD40L is upregulated by TNFalpha via a cyclooxygenase-1-independent, arachidonic acid-mediated oxidative stress mechanism.  相似文献   
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Neonatal Herpes simplex virus (HSV) pneumonia without apparent accompanying disseminated infection is a rare condition. We describe a case of neonatal pneumonia following maternal HSV type 1 viraemia in late pregnancy. A review of the literature shows that cases of HSV presenting as pneumonia in the first week of life are the most severe form of neonatal HSV.  相似文献   
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