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81.
Macrophage receptor with collagenous structure (MARCO) is a scavenger receptor expressed in peritoneal macrophages and in a subpopulation of macrophages in the marginal zone of the spleen and in the medullary cord of lymph nodes. By global gene expression analysis, it has been found that the MARCO mRNA was one of the most up-regulated in splenic dendritic cells (DCs) following lipopolysaccharide or bacterial activation and in granulocyte-macrophage colony-stimulating factor (GM-CSF)-treated microglial cells. Here we show that MARCO is expressed on splenic DCs at late time points after activation and that its expression correlates with profound changes in actin cytoskeleton organization in DCs and microglia. During maturation, DCs undergo profound rearrangements of actin cytoskeleton. Immature DCs are adherent with visible actin cables, while fully mature, MARCO-expressing, splenic DCs are nonadherent, round in shape, and have an actin cytoskeleton with a punctate distribution. The simple expression of MARCO was sufficient to induce these cytoskeleton modifications in DCs. MARCO-transfected immature DCs acquired a typical morphology of mature DCs and did not rearrange the actin cytoskeleton following activation. Moreover, DCs in which MARCO was knocked down did not reach the mature phenotype and maintained the typical morphology of transitional DCs. MARCO expression in DCs and microglial cells was also associated with a decrease of antigen internalization capacity. Thus, the MARCO receptor is important for actin cytoskeleton rearrangements and the down-regulation of antigen uptake function during DC and microglial cell maturation.  相似文献   
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INTRODUCTION: Biventricular pacing system implantation is a time-consuming and challenging procedure. A critical step in biventricular pacemaker implantation is coronary sinus (CS) cannulation. CS cannulation can be achieved either using dedicated guiding catheters (guiding catheter alone positioning strategy, GCA) or with the aid of an electrophysiology catheter advanced inside the guiding catheter (electrophysiology catheter aided positioning strategy, EPA). AIM OF THE STUDY: To evaluate whether the EPA technique is useful for reducing CS cannulation time compared to a conventional GCA technique. METHODS: Thirty-four consecutive patients were randomly assigned to the GCA (18 patients) or EPA (16 patients) CS cannulation strategy. RESULTS: Time to successful catheterization of CS was 5.0 +/- 2.4 min in the EPA group versus 10.1 +/- 5.4 min in the GCA group p = 0.004. Fluoroscopy time was 4.6 +/- 2.3 min in the EPA group versus 9.2 +/- 4.9 min in the GCA group p = 0.004. Total contrast dye volume to search and engage the CS ostium was 0.0 ml in the EPA group versus 14.3 +/- 3.4 ml in the GCA group p < 0.001. CONCLUSIONS: Cannulation of CS with the adjunct of an electrophysiology catheter to dedicated delivery systems significantly reduces procedural time, fluoroscopy time and contrast dye volume compared to a conventional strategy.  相似文献   
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Digestive Diseases and Sciences - Mesenteric cysts are defined as a heterogeneous group of intra-abdominal cystic lesions of the mesentery or omentum that may be found in any portion of the...  相似文献   
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Purpose

Granular cell tumors of the neurohypophysis are rare, solitary lesions, mostly presenting in the adult age. They rarely grow to a sufficient size to cause mass effect related symptoms and they may be found in most cases incidentally at autopsy. Because of their rarity as of now they have been described only as case reports or included in small clinical series.

Methods

We report a series of 11 patients, who underwent surgery for granular cell tumors of the neurohypophysis between 1996 and 2013 in a single center.

Results

Mean follow-up time after treatment was 92.2 months (range 9–231 months). Mean age at surgery was 40.7 years (range 12–66 years). There were 7 males (63.6 %) and 4 females (36.4 %). Main symptoms at presentation were: hyperprolactinemia (72.7 %), visual impairment (45.5 %) and headache (36 %). Except for 2 patients, all the others underwent surgery as primary treatment at our Institution, through a transsphenoidal (54.5 %) or a transcranial approach (45.5 %). Overall- and progression-free survival times for the entire series (calculated from the time of diagnosis) were 112.9 and 100.5 months respectively. There was one case of perioperative death in a patient who had undergone repeat transcranial surgery for residual tumor.

Conclusions

Although extremely rare, granular cell tumors of the neurohypophysis have to be considered in the differential diagnosis of suprasellar masses, to avoid misleading interpretation and consequent wrong therapeutic management. Early diagnosis, extensive tumor removal, opportune indication of adjuvant radiotherapy are the keys to manage these cases.
  相似文献   
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The possibility that isosorbide dinitrate (ISDN) inhibits platelet function in humans has been explored in vitro and in vivo. Incubation of citrated plateletrich plasma from healthy subjects with scalar concentrations (1.25, 12.5 and 125 μg/ml) of ISDN for 5 and 10 minutes resulted in a decrease in platelet aggregation after ADP, adrenaline, and arachidonic acid at the highest drug concentration (mean decrease: 72% [p < 0.01], 56% [p < 0.05] and 62% [p < 0.05], respectively, with the 10-minute incubation). Also, a significant reduction (30%) in generated thromboxane (TX)B2 levels was observed after arachidonic acid (p < 0.01). ISDN was then infused at rate of 4 mg/hour for 30 minutes in 11 patients with angina and at a rate of 30 mg/hour for 20 minutes in 8. The smaller dose, which caused minor changes in arterial pressure and heart rate, was accompanied by a marked, significant decrease in ADP- and adrenaline-induced aggregation, with a nadir at 60 minutes from the infusion stop (decreases of 40% and 51% respectively). Circulating platelet aggregates also decreased, with a minimum (? 41%, p < 0.05) at the end of the infusion. The higher infusion rate, causing marked hemodynamic effects, was not accompanied by the occurrence of clear antiplatelet effects. Thus, ISDN can affect platelet function both in vitro and in vivo. The in vivo effect occurs at lower concentrations than in vitro but is blunted when a marked hemodynamic response occurs.  相似文献   
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Background

The literature shows that the quality of communication is usually determined from a professional perspective. Patients or lay people are seldom involved in the development of quality indicators or communication.

Objective

To give voice to the lay people perspective on what constitutes ‘good communication’ by evoking their reactions to variations in physician communication.

Design

Lay people from four different countries watched the same videotaped standardized medical encounters and discussed their preferences in gender‐specific focus groups who were balanced in age groups.

Setting and participants

Two hundred and fifty‐nine lay people (64 NL, 72 IT, 75 UK and 48 BE) distributed over 35 focus groups of 6–8 persons each.

Main variables studied

Comments on doctors'' behaviours were classified by the GULiVer framework in terms of contents and preferences.

Results

Participants prevalently discussed ‘task‐oriented expressions’ (39%: competency, self‐confident, providing solutions), ‘affective oriented/emotional expressions'' (25%: empathy, listening, reassuring) and ‘process‐oriented expressions'' (23%: flexibility, summarizing, verifying). ‘Showing an affective attitude’ was most appreciated (positive percentage within category: 93%, particularly facilitations and inviting attitude), followed by ‘providing solution’ (85%). Among disfavoured behaviour, repetitions (88%), ‘writing and reading’ (54%) and asking permission (42%) were found.

Conclusions

Although an affective attitude is appreciated by nearly everybody, people may vary widely in their communication needs and preferences: what is ‘good communication’ for one person may be disliked or even a source of irritation for another. A physician should be flexible and capable of adapting the consultation to the different needs of different patients. This challenges the idea of general communication guidelines.  相似文献   
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