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Human arterial wall cells secrete factors that are chemotactic for monocytes. 总被引:11,自引:4,他引:11 下载免费PDF全文
T Mazzone M Jensen A Chait 《Proceedings of the National Academy of Sciences of the United States of America》1983,80(16):5094-5097
Macrophages and arterial smooth muscle cells comprise the cellular components of the atherosclerotic plaque. The vessel wall accumulation of macrophages occurs by a process of increased circulating monocyte migration into the vessel wall. In these studies it is demonstrated that human macrophages and arterial smooth muscle cells in culture secrete potent chemotactic factors for freshly isolated human monocytes. In contrast, human fibroblast-conditioned medium has no chemotactic activity. The effect of macrophage-conditioned medium is a function of macrophage differentiation and can be potentiated by macrophage activation. These results suggest that secretory products of human macrophages and arterial smooth muscle cells may be important stimuli for increased monocyte migration into the vessel wall in vivo. 相似文献
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Contrast-enhanced gray-scale harmonic ultrasound in the efficacy assessment of ablation treatments for hepatocellular carcinoma. 总被引:5,自引:0,他引:5
Maurizio Pompili Laura Riccardi Marcello Covino Brunella Barbaro Carmine Di Stasi Ruggero Orefice Giovanni Gasbarrini Gian Ludovico Rapaccini 《Liver international》2005,25(5):954-961
BACKGROUND: The aim of this study was to compare contrast-enhanced gray-scale harmonic ultrasound with multiphasic spiral computed tomography in the assessment of treatment efficacy of non-surgically treated HCC. METHODS: We studied 56 HCCs treated by percutaneous ethanol injection (31 cases), radiofrequency ablation (three cases), trans-arterial chemoembolization (12 cases), and combined treatment (10 cases). The efficacy of therapies was blindly assessed by multiphasic computed tomography and gray-scale harmonic ultrasound with a second-generation contrast agent (sulfur hexafluoride). RESULTS: On computed tomography 30 tumors (53.6%) showed complete necrosis, while 26 lesions (45.4%) were still viable. On contrast-enhanced ultrasound examination 33/56 nodules (58.9%) had no contrast enhancement in the arterial phase, while 23/56 lesions (41.1%) were still vascularized. All the nodules assessed as completely necrotic on computed tomography did not show arterial enhancement on contrast-enhanced ultrasound and diagnostic agreement was found in 53/56 cases (94.6%) (P<0.001). Contrast-enhanced ultrasound demonstrated relative sensitivity and specificity of 87.0% and 98.4%. CONCLUSIONS: Contrast-enhanced harmonic ultrasound is promising in the efficacy evaluation of ablation treatments for HCC. Nodules vascularized in the arterial phase on contrast harmonic ultrasound should be considered still viable and addressed to additional treatment without further evaluation. 相似文献
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De Luca N Izzo R Iaccarino G Malini PL Morisco C Rozza F Iovino GL Rao MA Bodenizza C Lanni F Guerrera L Arcucci O Trimarco B 《Journal of hypertension》2005,23(7):1417-1423
BACKGROUND: Inadequate blood pressure (BP) control could be due to incorrect management of hypertensives caused by the lack of interaction between general practitioners (GP) and hypertension specialists. OBJECTIVES: To test the effectiveness on BP and total cardiovascular risk (TCVR) control of an internet-based digital network connecting specialists and GPs. METHODS: We created a network among the Hypertension Clinic, Federico II University (Naples, Italy), 23 hospital-based hypertension clinics and 60 GPs from the area (CampaniaSalute Network, CS). Randomized GPs enrolled in CS could update online records of patients (n = 1979). As a control, we included 2045 patients referred to the specialist clinics by GPs from outside the network. All patients completed a 2-year follow-up. RESULTS: CS provided a larger reduction in BP [systolic/diastolic BP (SBP/DBP): 7.3 +/- 0.4/5.4 +/- 0.3 versus 4.1 +/- 0.4/3.1 +/- 0.26 mmHg, CS versus control; P < 0.001 for both] and percentage of patients with BP < 140/90 mmHg (CS versus control: baseline, 33 versus 34%, NS; end of follow-up, 51 versus 47%, chi = 13.371; P < 0.001). A European Society of Hypertension-European Society of Cardiology (ESH/ESC) TCVR score was calculated [from 1 (average) to 5 (very high TCVR)]. The CS group showed a reduction in the mean TCVR score (CS: from 3.5 +/- 0.02 to 3.2 +/- 0, P < 0.01, ANOVA; control group: 3.5 +/- 0.03 to 3.4 +/- 0.03, NS) and, accordingly, fatal and non-fatal major cardiovascular events (MACE) were less frequent (2.9 versus 4.3%; chi = 5.047, P < 0.02). CS predicts fewer MACE in multiple binary regression analysis (beta:-7.27, P < 0.008) reducing the risk for MACE compared to control [odds ratio (OR): 0.838; 95% confidence interval (CI): 0.73-0.96]. CONCLUSION: Our results support the idea that telemedicine can achieve better control of BP and TCVR. 相似文献
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Michel Desmurget Nathalie Richard Sylvain Harquel Pierre Baraduc Alexandru Szathmari Carmine Mottolese Angela Sirigu 《Proceedings of the National Academy of Sciences of the United States of America》2014,111(15):5718-5722
Complex motor responses are often thought to result from the combination of elemental movements represented at different neural sites. However, in monkeys, evidence indicates that some behaviors with critical ethological value, such as self-feeding, are represented as motor primitives in the precentral gyrus (PrG). In humans, such primitives have not yet been described. This could reflect well-known interspecies differences in the organization of sensorimotor regions (including PrG) or the difficulty of identifying complex neural representations in peroperative settings. To settle this alternative, we focused on the neural bases of hand/mouth synergies, a prominent example of human behavior with high ethological value. By recording motor- and somatosensory-evoked potentials in the PrG of patients undergoing brain surgery (2–60 y), we show that two complex nested neural representations can mediate hand/mouth actions within this structure: (i) a motor representation, resembling self-feeding, where electrical stimulation causes the closing hand to approach the opening mouth, and (ii) a motor–sensory representation, likely associated with perioral exploration, where cross-signal integration is accomplished at a cortical site that generates hand/arm actions while receiving mouth sensory inputs. The first finding extends to humans’ previous observations in monkeys. The second provides evidence that complex neural representations also exist for perioral exploration, a finely tuned skill requiring the combination of motor and sensory signals within a common control loop. These representations likely underlie the ability of human children and newborns to accurately produce coordinated hand/mouth movements, in an otherwise general context of motor immaturity.Since Penfield’s original work, it is commonly assumed that complex motor responses are produced by combining elemental movements that are independently represented at different neural sites (1). However, the generality of this model was recently challenged in nonhuman primates, where reaching, grasping, defensive, and hand/mouth movements have been found to be represented as complex motor primitives in independent circumscribed territories of the precentral gyrus (PrG) (2–4). To account for this observation, it was suggested that complex motor primitives have emerged during primate evolution to optimize the production of ethologically relevant behaviors (4). However, to date, direct evidence is lacking that such integrated representations of ethologically relevant movements also exist in humans. This may have two different origins.First, it could be that complex ethologically relevant representations exist in human PrG but have not yet been described, due to the difficulty of identifying neural representations associated with the expression of elaborate sensorimotor behaviors in peroperative contexts. With respect to this point, Penfield and other researchers have clearly reported complex multijoint motor responses following cortical stimulation (5–8), including concurrent movements of the hand and mouth (9). Nevertheless, these movements were not investigated systematically in several subjects, described in detail, or related to the existence of integrated neural representations for ethologically relevant behaviors. An obstacle to the investigation of these representations could have been the tendency to stop the stimulation following movement onset. This was explicitly acknowledged by Penfield in the following terms: “the stimulating electrode has frequently been removed at the first evidence of response, and thus the opportunity of producing more of the elaborate synergic responses may have been missed” (6).At a second level, it could be that the PrG does not contain functional representations of complex ethologically relevant behaviors in humans. This possibility is consistent with the existence of substantial dissimilarities in sensorimotor organization between human and nonhuman primates (10, 11). Interestingly, these dissimilarities are well documented for the precentral region mediating ethological synergies in monkeys. In this species, electrical stimulation in the rostral part of PrG evokes coordinated hand-to-mouth movements (12). These movements are part of the behavioral repertoire of the primate newborns (13), which is consistent with the observation that the rostral (phylogenetically oldest) part of PrG lacks cortico-motoneural cells and generates movements by recruiting the integrative mechanisms of the spinal cord through descending projections that are mature at birth (14). However, in human infants, the difficulty of evoking motor responses through electrical stimulation of the rostral PrG does not seem consistent with the existence of early mature descending projections (15, 16). Also, in adults, transcranial magnetic stimulation studies have suggested, in apparent contrast with monkey data, that late-maturing cortico-motoneural cells are present in the human rostral PrG (17, 18).The main aim of this study was to determine whether integrated neural representations of complex actions can be found in the human PrG. We investigated this possibility by studying the neural bases of hand/mouth synergies, a salient example of early and elaborate human behavior with high ethological value (19–21). To this end, motor and somatosensory mapping were combined in children and adult patients undergoing brain surgeries. 相似文献
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Su Ling Tee Andrew Sindone Simon Roger John Atherton John Amerena Michael D'Emden Jonathan Erlich Carmine De Pasquale 《Internal medicine journal》2020,50(6):659-666
Hyponatraemia is common in heart failure (HF). It is estimated that over 20% of patients admitted to hospital with HF have hyponatraemia. It has also been repeatedly shown to be a surrogate marker of increased morbidity and mortality in this specific population. This review focuses on the pathophysiology of hyponatraemia through the activation of neurohormonal cascades in HF, the clinical implications of sustained hyponatraemia and treatment options in the management of this challenging phenomenon. 相似文献
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