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1.

Background

Since recent reports have shown that (-)-Epigallocatechin-3-gallate (EGCG) could be used for treating proliferative and inflammatory disorders, we explored its use for the management of corneal chemical burns.

Materials and methods

Initially, EGCG was assayed on the rabbit corneal epithelial cell line RCE1(5T5) to establish the best testing conditions, and to avoid unwanted outcomes in the experimental animals. Then, we studied its effects on cell proliferation, cell cycle progression and cell differentiation. Afterwards, we instilled EGCG in experimental grade II corneal alkali burns in mice, three times a day up to 21 days, and evaluated by slit lamp examination and histological sections of corneal epithelial, corneal endothelial and stromal edema, as well as the presence of inflammatory cells and neovascularization.

Results

EGCG reduced cell growth and led to a decline in the proportion of proliferative cells in a concentration dependent manner. At 10 μM, EGCG promoted cell differentiation, an effect not related with apoptosis or cytotoxicity. When 10 μM EGCG was instilled in corneal alkali burns in mice three times a day up to 21 days, EGCG significantly reduced corneal opacity and neovascularization. The improved clinical appearance of the cornea was associated to a controlled epithelial growth; epithelial morphology was similar to that observed in normal epithelium and contrasted with the hyperproliferative, desquamating epithelium observed in control burn wounds. EGCG reduced corneal, stromal and endothelial edema, and wound inflammation.

Conclusion

This work constitutes the first evidence for the use of EGCG in the acute phase of a corneal alkali burn, representing a possible novel alternative to improve patient outcomes as an add-on therapy.  相似文献   
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The main purpose of this study was to assess whether it is possible to improve the prognostic impact of international prognostic index (IPI) score by combining it with peripheral blood counts. Thus, we evaluated the prognostic power of lymphocyte, neutrophil, and monocyte counts in 520 patients with diffuse large B cell lymphoma treated with R-CHOP, confirming that these parameters have a strong impact on overall survival (OS). Using revised IPI (R-IPI), 44% of patients were categorized as poor-risk and showed an OS at 5 years of 46%. As OS at 5 years of the 520 patients is 67%, it is clearly evident that R-IPI tends to overestimate the proportion of patients with poor prognosis. Accordingly, in an attempt to improve the discriminating power of R-IPI, we evaluated and compared three different scores by combining the neutrophil lymphocyte ratio (NLR) and absolute monocyte count (AMC) with the following values: (a) IPI score 3-5, (b) age > 60 years and performance status, (c) age ≥ 65 years and LDH > ULN. The three indexes studied, had a similar 5 years OS for the high-risk group (46%-52%), but the proportion of patients classified as poor-risk were 37%, 20%, and 32%, respectively, which are lower than 44% identified with R-IPI. Thus, while R-IPI overestimates the number of high-risk patients, after applying our models, it is possible to recognize patients who are truly at high-risk. Of the three scores, the most accurate appears to be that based on NLR, AMC, LDH > ULN and age ≥ 65 years, which identifies 32% of high-risk patients, correlating well with what is seen in clinical practice.  相似文献   
5.
Cholangiocarcinoma(CCA) is a malignant tumor of the biliary system and includes, according to the anatomical classification, intra hepatic CCA(iCCA),hilar CCA(hCCA) and distal CCA(dCCA). Hilar CCA is the most challenging type in terms of diagnosis, treatment and prognosis. Surgery is the only treatment possibly providing long-term survival, but only few patients are considered resectable at the time of diagnosis. In fact, tumor's extension to segmentary or subsegmentary biliary ducts, along with large lymph node involvement or intrahepatic metastases, precludes the surgical approach. To achieve R0 margins is mandatory for the disease-free survival and overall survival. In case of unresectable locally advanced hCCA, radiochemotherapy(RCT) as neoadjuvant treatment demonstrated to be a therapeutic option before either hepatic resection or liver transplantation. Before liver surgery, RCT is believed to enhance the R0 margins rate. For patients meeting the Mayo Clinic criteria, RCT prior to orthotopic liver transplant(OLT) has proved to produce acceptable 5-years survivals. In this review, we analyze the current role of neoadjuvant RCT before resection as well as before OLT.  相似文献   
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Background

Total ankle replacement (TAR) represents an alternative to fusion for the treatment of end-stage ankle osteoarthritis. The aim of the present study was to retrospectively assess the frequency of infections between TARs with anterior and lateral transfibular approach at 12-months follow-up.

Methods

81 TARs through an anterior approach and 69 TARs through a lateral approach were performed between May 2011 and July 2015. We compared surgical time and tourniquet time, as well as superficial and deep infections frequency during the first 12 postoperative months.

Results

In the anterior approach group, there were 3 (3.7%) deep infections and 4 (4.9%) superficial wound infections. In the lateral approach group, there were 1 (1.4%) deep infection and 2 superficial wound infections (2.9%). There were not statistically significant differences between the groups. There was a significant difference between anterior approach (115 minutes) and lateral approach group (179 minutes) in terms of surgical time (P < 0.001).

Conclusions

The frequency of superficial and deep periprosthetic infections during the first postoperative year was not significantly different in the lateral approach group compared to the anterior approach group, despite the significantly longer surgical time in the lateral transfibular approach group.  相似文献   
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The fate of isoprene inhaled by rats: comparison to butadiene   总被引:1,自引:0,他引:1  
Isoprene (2-methyl-1,3-butadiene), a volatile monomer occurring in the natural environment and used in the manufacture of elastomers, is a close chemical relative of the animal carcinogen 1,3-butadiene. To obtain toxicokinetic data for inhaled isoprene, male F344 rats were exposed in groups of 30 to 14C-labeled isoprene vapor at four concentrations from 8 to 8200 ppm. The percentage of the inhaled isoprene that was metabolized decreased with increasing exposure concentration. The percentage of the total metabolites (that is, non-isoprene-retained 14C) excreted in urine and feces or expired was determined as a function of vapor concentration. About 75% of the total metabolites was excreted in urine. This was independent of inhaled isoprene concentration. After exposure to 8200 ppm, a larger percentage of the metabolites was excreted in feces than after exposure to lower concentrations. Using vacuum line techniques, blood metabolite concentrations were determined as functions of both vapor concentration and exposure duration. At one exposure concentration (1480 ppm) metabolites were measured in the nose, lungs, liver, kidney, and fat, as well as in blood. A mutagenic metabolite, isoprene diepoxide, was tentatively identified in all tissues examined. Between 0.0018 and 0.031% of the inhaled 14C label was tentatively identified as this metabolite in blood. The relative amount of the metabolites present in blood was highest for low concentrations of inhaled isoprene and for shorter exposure durations. Body fat appeared to be a reservoir for both isoprene metabolites and isoprene itself. The appearance of metabolites in the respiratory tract after short exposure durations together with low blood concentrations of isoprene indicated that substantial metabolism of inhaled isoprene in the respiratory tract may occur.  相似文献   
10.
Head movement presents a continuing problem in PET studies. Head restraint minimizes movement but is unreliable, resulting in the need to develop alternative strategies. These include frame-by-frame (FBF) realignment or use of motion tracking (MT) during the scan to realign PET acquisition data. Here we present a comparative analysis of these 2 methods of motion correction. METHODS: Eight volunteers were examined at rest using (11)C-raclopride PET with the radioligand administered as a bolus followed by constant infusion to achieve steady state. Binding potential (BP) was estimated using the ratio method during 2 periods of the scan at steady state. Head movement was compensated by using coregistration between frames (FBF) and 3 methods using MT measurements of head position acquired with a commercially available optical tracking system. RESULTS: All methods of realignment improved test-retest reliability and noise characteristics of the raw data, with important consequences for the power to detect small changes in radiotracer binding, and the potential to reduce false-positive and false-negative results. MT methods were superior to FBF realignment using coregistration on some indices. CONCLUSION: Such methods have considerable potential to improve the reliability of PET data with important implications for the numbers of volunteers required to test hypotheses.  相似文献   
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