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Dendritic cells (DCs) are the most powerful professional antigen-presenting cells (APC), specializing in capturing antigens and stimulating T-cell-dependent immunity. In this study we report the generation and characterization of functional DCs derived from both steady-state bone marrow (BM) and circulating haemopoietic CD34+ cells from 14 individuals undergoing granulocyte colony-stimulating factor (G-CSF) treatment for peripheral blood stem cells (PBSC) mobilization and transplantation. Clonogenic assays in methylcellulose showed an increased frequency and proliferation of colony-forming unit-dendritic cells (CFU-DC) in circulating CD34+ cells, compared to that of BM CD34+ precursors in response to GM-CSF and TNF-α with or without SCF and FLT-3L. Moreover, peripheral blood (PB) CD34+ cells generated a significantly higher number of fully functional DCs, as determined by conventional mixed lymphocyte reactions (MLR), than their BM counterparts upon different culture conditions. DCs derived from mobilized stem cells were also capable of processing and presenting soluble antigens to autologous T cells for both primary and secondary immune response. Replacement of the early-acting growth factors SCF and FLT-3L with IL-4 at day 7 of culture of PB CD34+ cells enhanced both the percentage of total CD1a+ cells and CD1a+CD14? cells and the yield of DCs after 14 d of incubation. In addition, the alloreactivity of IL-4-stimulated DCs was significantly higher than those generated in the absence of IL-4. Furthermore, autologous serum collected during G-CSF treatment was more efficient than fetal calf serum (FCS) or two different serum-free media for large-scale production of DCs. Thus, our comparative studies indicate that G-CSF mobilizes CD34+ DC precursors into PB and circulating CD34+ cells represent the optimal source for the massive generation of DCs. The sequential use of early-acting and intermediate-late-acting colony-stimulating factors (CSFs) as well as the use of autologous serum greatly enhanced the growth of DCs. These data may provide new insights for manipulating immunocompetent cells for cancer therapy.  相似文献   
83.

Purpose

Hepatic fatty acid synthesis is influenced by several nutritional and hormonal factors. In this study, we have investigated the effects of distinct experimental diets enriched in carbohydrate or in fat on hepatic lipogenesis.

Methods

Male Wistar rats were divided into four groups and fed distinct experimental diets enriched in carbohydrates (70 % w/w) or in fat (20 and 35 % w/w). Activity and expression of the mitochondrial citrate carrier and of the cytosolic enzymes acetyl-CoA carboxylase and fatty acid synthetase were analyzed through the study with assessments at 0, 1, 2, 4, and 6 weeks. Liver lipids and plasma levels of lipids, glucose, and insulin were assayed in parallel.

Results

Whereas the high-carbohydrate diet moderately stimulated hepatic lipogenesis, a strong inhibition of this anabolic pathway was found in animals fed high-fat diets. This inhibition was time-dependent and concentration-dependent. Moreover, whereas the high-carbohydrate diet induced an increase in plasma triglycerides, the high-fat diets determined an accumulation of triglycerides in liver. An increase in the plasmatic levels of glucose and insulin was observed in all cases.

Conclusions

The excess of sucrose in the diet is converted into fat that is distributed by bloodstream in the organism in the form of circulating triglycerides. On the other hand, a high amount of dietary fat caused a strong inhibition of lipogenesis and a concomitant increase in the level of hepatic lipids, thereby highlighting, in these conditions, the role of liver as a reservoir of exogenous fat.  相似文献   
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Clinical Rheumatology - Biologic disease-modifying antirheumatic drugs (bDMARDs) play a pivotal role in the treatment of psoriatic arthritis (PsA). Despite this, their discontinuation due to...  相似文献   
86.
Restoring the bladder glycosaminoglycans layer has recently been introduced as prophylactic treatment for recurrent urinary tract infections. Herein, we analyze the latest main clinical and experimental studies to support this therapeutic option. An electronic research was carried out in the most common databases in order to identify any published studies. Retrieved studies were categorized as experimental or clinical according to their setting. For the clinical studies, the evidence level was assigned. A total of 13 laboratory studies showed how bladder glycosaminoglycans instillations act: attenuation of the inflammation process, reduction of bladder contraction amplitude and frequency, reduction of epithelium damage, and lower bacterial growth in urine and tissue samples. Likewise, two randomized clinical trials with grade 2 evidence level and two case series with grade 4 evidence level reported glycosaminoglycans as an alternative to reduce episodes and to prolong recurrence time in patients with recurrent urinary tract infections. At least 12 months of follow up was completed. No serious adverse events were reported. Compared with a placebo, in one randomized study a significantly higher maximum cystometric capacity was obtained, whereas in the other study a significant increase in quality of life scores was reported too. An improvement in the urinary symptoms score was reported by the two randomized trials. Although the clinical use of glycosaminoglycans replacement therapy for recurrent urinary tract infections is supported by a small number of clinical studies with different evidence levels, the laboratory studies show that glycosaminoglycans could have a protective role against inflammatory factors, supporting the idea “to restore the glycosaminoglycans bladder layer to prevent chronic disease course”.  相似文献   
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The authors reviewed the evidence-based data available in literature, regarding the treatment of the female urinary incontinence and suggested potential therapeutic strategies to approach a woman with urinary incontinence.  相似文献   
90.
Objectives:To investigate whether lesion imaging features may condition the outcome of CT-guided lung biopsy (CTLB) and to develop a scoring system of biopsy outcome prediction.Methods:This is a single center retrospective study on 319 CTLBs that were performed in 319 patients (167 males/152 females, mean age 68 ± 12.2). Uni- and multivariate analysis were performed aiming to assess the imaging features that are likely to be correlated to a negative biopsy outcome and patients were stratified in groups accordingly.Results:Technical success was 100%. 78% of the biopsies (250/319) led to a concrete histology report (218 malignant/32 benign). The remaining lesions led to concrete histology at a second attempt that occurred on a later time. Multivariate analysis revealed increased risk of inconclusive result for nodules with low fludeoxyglucose uptake [odds ration (OR) = 2.64, 95% confidence interval (CI) 1.4–4.97; p = 0.003], for nodules with diameter smaller than 18 mm (OR = 2.03, 95% CI 1.14–3.62; p = 0.017) and for nodules that are located in one of the lung bases (OR = 1.96, 95% CI 1.06–3.62; p = 0.033). Three different groups of patients were identified accordingly with low (<30%), medium (30–50%) and high (>50%) probability of obtaining an inconclusive biopsy sample.Conclusion:This study confirms that percutaneous CT-guided biopsy in nodules that are either small in diameter or present low positron emission tomography-fludeoxyglucose uptake or are in one of the lung bases may lead to inconclusive histology. This information should be factored when planning percutaneous biopsies of such nodules in terms of patient informed consent and biopsy strategy.Advances in knowledge:Inconclusive histology after lung biopsy may be subject to factors irrelevant to technical success. Lung biopsy histology outcomes may be predicted and avoided after adequate planning.  相似文献   
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