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1.
Dendritic cells (DC) are increasingly explored as cellular vaccines for tumor immunotherapy. In most reported DC-based cancer vaccine trials, DC have been pulsed with soluble tumor antigen-derived peptide ligands of MHC molecules. Considering that the half-life of peptide/MHC complexes on the cell surface is relatively short and that soluble exogenous protein antigens cannot be efficiently processed via the MHC class I-processing pathway, the current vaccination procedure is not optimal for the induction of strong T cell responses aiming at tumor rejection. Recently, we have shown that antigen presentation can be prolonged when synthetic peptides were encapsulated in biodegradable poly(D,L-lactide-co-glycolide) (PLGA) microspheres (MS) for uptake by DC. In the present study, we investigated the phenotypic and functional consequences of MS uptake by human monocyte-derived dendritic cells (MoDC) in vitro. We found that immature MoDC that were prepared in serum free media suitable for clinical application were able to phagocytose high numbers of MS, while matured MoDC showed a reduced capacity for phagocytosis of MS. The ingestion of MS did not change the cell surface expression of CD80, CD83, CD86 and HLA-DR of immature and mature DC, suggesting that MS uptake did not induce DC maturation but that maturation by cytokines or LPS was unaltered in the presence of MS. Furthermore, MS-loaded mature MoDC expressed normal levels of the chemokine receptor CCR7 and migrated as efficiently towards CCL19 or CCL21 as unloaded MoDC. DC viability and the secretion of TNF-alpha and IL-12 was not significantly changed by MS loading. Taken together, our data indicate that PLGA-MS loading has no negative effects on the pivotal properties of MoDC in vitro. It should therefore be feasible to further develop this antigen loading strategy for clinical use in immunotherapy against viral infections and tumors.  相似文献   
2.
Cellular inflammatory responses in human allergic skin reactions   总被引:2,自引:0,他引:2  
To define better the role of inflammation in the response to pollen antigens, we have used our skin chamber model to study inflammatory cells recovered from the sites of ongoing allergic reactions. In 15 atopic subjects, paired skin blister sites were simultaneously challenged with ragweed- or grass-pollen antigen or buffer for 5 hours. There were 10 times as many cells recovered at antigen (20.7 X 10(5)) than at buffer (2.0 X 10(5)) sites, p less than 0.005; greater than 97% of the cells recovered were neutrophils. The number of cells recovered at the antigen sites correlated with the total amount of histamine released (r = 0.57; p less than 0.05) but not with the extinction dilution skin test reactivity nor with the intensity of the late cutaneous allergic response measured 6 hours after the injection of antigen. Phase-contrast microscopic examination of the cells recovered from the antigen sites demonstrated that 82% to 95% were polarized compared to 0% to 1.5% of autologous blood neutrophils obtained simultaneously from the peripheral blood. Antigen site cells were as capable of serum-dependent phagocytosis as peripheral blood neutrophils. There was no significant difference in the migratory response to buffer, the chemoattractant N-formyl-methionyl-leucyl-phenylalanine, or leukotriene B4, but there was a significantly decreased response to platelet-activating factor when the cells recovered from antigen sites were compared to autologous blood neutrophils.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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BACKGROUND: Open tension-free methods of groin hernia repair have been widely adopted despite little rigorous evaluation. METHODS: Information was assimilated from all randomized or quasi-randomized trials comparing open mesh with open non-mesh methods to assess benefits and safety. Electronic databases were searched and members of the EU Hernia Trialists Collaboration consulted to identify trials. Prespecified data items were extracted from reports, and quantitative or, if not possible, qualitative meta-analysis was performed. RESULTS: Fifteen eligible trials, which included 4005 participants, were identified. There were similar numbers of complications in each group, with few data to address short-term pain and length of stay in hospital. Return to usual activities was quicker in the mesh group for seven of ten trials (P not significant). There were fewer reported recurrences in the mesh groups: overall 21 (1.4 per cent) of 1513 versus 72 (4.4 per cent) of 1634 (odds ratio 0.39 (95 per cent confidence interval 0.25-0. 59); P < 0.001). CONCLUSION: Although the rigorous search maximized trial identification, formal meta-analysis was limited by the variation in trial reporting. Within the data available, mesh repair was associated with fewer recurrences.  相似文献   
4.
BACKGROUND: The place of laparoscopic groin hernia repair remains controversial. Individual randomized controlled trials alone have not provided statistically reliable results when considering recurrence, potentially serious complications and chronic pain. METHODS: A rigorous systematic review was performed of published data from all relevant randomized or quasi-randomized trials. Electronic databases were searched and members of the EU Hernia Trialists Collaboration consulted to identify trials. Prespecified data items were extracted from reports and, where possible, quantitative meta-analysis was performed. RESULTS: Thirty-four published reports of eligible trials were included, involving 6804 participants. Sample sizes ranged from 20 to 1051, with follow-up from 6 weeks to 36 months. Duration of operation was longer in the laparoscopic groups (P < 0.001, Sign test). Operative complications were uncommon for both methods, but visceral and vascular injuries were more frequent in the laparoscopic group (4.7 per 1000 versus 1. 1 per 1000). Postoperative pain was less among laparoscopic groups (P = 0.08). Length of hospital stay did not differ significantly between groups (P = 0.50), but return to usual activity was earlier for laparoscopic groups (P < 0.001). Chronic pain and numbness were reported for only a small minority of trials. Overall, recurrences did not differ between groups, but comparison of laparoscopic with open non-mesh repair favoured laparoscopic methods, significantly so for transabdominal preperitoneal repair (Peto odds ratio 0.56 (95 per cent confidence interval 0.33-0.93); P = 0.026). CONCLUSION: Although the rigorous search maximized trial identification, variation in trial reporting made formal meta-analysis difficult. Laparoscopic repair was associated with less postoperative pain and more rapid return to normal activities, but it takes longer to perform and may increase the risk of rare, but serious, complications.  相似文献   
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We studied the influence of sepsis on muscle protein synthesis and degradation in vivo and in muscles, incubated flaccid or at resting length. Sepsis was induced in rats by cecal ligation and puncture (CLP). Control rats were sham-operated. A flooding dose of 14C-phenylalanine was used to determine muscle protein synthesis rate in vivo, and protein breakdown was calculated from the difference between protein synthesis and growth rates. Protein synthesis rate in vitro was assessed by determining incorporation of 14C-phenylalanine into protein in incubated extensor digitorum longus (EDL) and soleus (SOL) muscles. Total and myofibrillar protein breakdown rates were determined from release into incubation medium of tyrosine and 3-methylhistidine (3-MH), respectively. Muscle protein synthesis rate in vivo was reduced by 35%, similar to the reduction observed in muscles incubated flaccid or at resting length. The calculated protein breakdown rate in vivo was increased by 31% in septic rats. In incubated muscles, the increase in total protein breakdown (ie, tyrosine release) during sepsis was almost identical in muscles incubated flaccid or at resting length, ie, 83% to 88% in EDL and 47% to 49% in SOL. Myofibrillar protein degradation in vitro (ie, 3-MH release) was increased approximately 10-fold in EDL muscles incubated flaccid or at resting length, but was not significantly affected by sepsis in SOL. Results suggest that sepsis-induced changes in protein synthesis observed in muscles incubated either flaccid or at resting length reflect changes in vivo. Changes in protein breakdown were qualitatively similar in vivo and in vitro, but results in incubated muscles may overestimate the increase in muscle proteolysis caused by sepsis.  相似文献   
8.

Aim:

The most recent study on the clinicopathological features of gastric carcinoma from the University College Hospital (UCH), Ibadan, was done in 2000. The aim of this study is to update the knowledge on the clinicopathological features of gastric carcinoma diagnosed in the Pathology Department of the UCH Ibadan between 2000 and 2011.

Materials and Methods:

This was a 12-year retrospective review of clinical and demographic data and the histopathological features of gastric cancers diagnosed at the Pathology Department of the UCH. The chi square test, Fisher''s exact test, and the t-independent test were used as applicable in the statistical analyses.

Results:

A total of 117 cases of gastric carcinoma were histologically diagnosed at the Pathology Department of UCH, Ibadan in this period giving a relative ratio frequency of 1.38% for all cancers. It represented 18.4% of all gastrointestinal tract malignancies diagnosed in the same period. There was a male preponderance with male:female ratio of 1.72:1; the middle-aged and elderly made up about 76.1% of cases. The disease was clinically and histologically advanced in 92.8% of cases. Gastric tumours were predominantly antral/ pyloric in 80% of cases and exophytic in 62.3% of cases. The intestinal histotype constituted 47.0% cases although a rise in the diffuse histological type was observed.

Conclusion:

There is a decline in the relative ratio frequency of gastric carcinoma in Ibadan; and a fall in the rate of the intestinal type of gastric carcinoma relative to the diffuse type when compared to previous studies from our centre.  相似文献   
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