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1.
We analyzed the characteristics of the inflammatory response occurring in blood during pulmonary infections in human immunodeficiency virus (HIV)-infected patients. A prospective study of consecutive hospital admissions of HIV-infected patients with new-onset radiologic pulmonary infiltrates was carried out in a tertiary university hospital from April 1998 to May 2001. Plasma cyclic AMP receptor protein (CRP), interleukin 1beta (IL-1beta), IL-6, IL-8, IL-10, and tumor necrosis factor alpha (TNF-alpha) levels were determined at the time of admission and 4, 5, and 6 days later. Patients were included in a protocol addressed to study etiology and outcome of disease. A total of 249 episodes of infection were included, with the main diagnoses being bacterial pneumonia (BP) (118 episodes), Pneumocystis carinii pneumonia (PCP) (41 episodes), and mycobacteriosis (36 episodes). For these three patient groups, at the time of admission the median CRP and cytokine levels were as follows: CRP, 10.2, 3.8 and 5 mg/dl, respectively (P = 0.0001); IL-8, 19, 3, and 2.9 pg/ml (P = 0.045); and TNF-alpha, 46.4, 44, and 75 pg/ml, respectively (P = 0.029). There were no significant differences in levels of IL-1beta, IL-6, or IL-10 among the patient groups. A total of 23 patients died. At the time of admission, HIV-infected patients with BP had higher plasma CRP and IL-8 levels than did PCP and mycobacteriosis patients. TNF-alpha levels were higher in patients with mycobacteriosis. An elevated IL-8 level (>61 pg/ml) at the time of admission was an independent factor associated with higher mortality (odds ratio, 12; 95% confidence interval, 1.2 to 235.5).  相似文献   
2.
The isolation of two plasmind-like ciruclar DNAs, measuring 52 and 42 kbp, from anAcanthamoeba sp. from the Philippines has led to the demonstration of a bacterial endosymbiont occurring in this free-living amoeba. The 52-kbp band hybridized with a short sequence of cytochrome b gene and was identified as the mitochondrial DNA, whereas the 42-kbp band was identified as plasmid DNA of the bacterial symbionts on the basis of electron microscopy. The endosymbionts are gram-negative, rod-shaped bacteria measuring approximately 1.3×0.43 m and numbering about eight to ten cells per section. They are randomly distributed in both cysts and trophozoites and are surrounded neither by a phagolysosomal membrane nor by a clear or electrontranslucent region. The endosymbiont membrane appears to have a close association with ribosomes, which are seen to be more concentrated within the vicinity of the symbionts than elsewhere within the cytoplasm. Attempts to grow the symbionts and the amoebae separately have failed.  相似文献   
3.
We analyzed the characteristics of the inflammatory response occurring in blood during pulmonary infections in human immunodeficiency virus (HIV)-infected patients. A prospective study of consecutive hospital admissions of HIV-infected patients with new-onset radiologic pulmonary infiltrates was carried out in a tertiary university hospital from April 1998 to May 2001. Plasma cyclic AMP receptor protein (CRP), interleukin 1β (IL-1β), IL-6, IL-8, IL-10, and tumor necrosis factor alpha (TNF-α) levels were determined at the time of admission and 4, 5, and 6 days later. Patients were included in a protocol addressed to study etiology and outcome of disease. A total of 249 episodes of infection were included, with the main diagnoses being bacterial pneumonia (BP) (118 episodes), Pneumocystis carinii pneumonia (PCP) (41 episodes), and mycobacteriosis (36 episodes). For these three patient groups, at the time of admission the median CRP and cytokine levels were as follows: CRP, 10.2, 3.8 and 5 mg/dl, respectively (P = 0.0001); IL-8, 19, 3, and 2.9 pg/ml (P = 0.045); and TNF-α, 46.4, 44, and 75 pg/ml, respectively (P = 0.029). There were no significant differences in levels of IL-1β, IL-6, or IL-10 among the patient groups. A total of 23 patients died. At the time of admission, HIV-infected patients with BP had higher plasma CRP and IL-8 levels than did PCP and mycobacteriosis patients. TNF-α levels were higher in patients with mycobacteriosis. An elevated IL-8 level (>61 pg/ml) at the time of admission was an independent factor associated with higher mortality (odds ratio, 12; 95% confidence interval, 1.2 to 235.5).  相似文献   
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5.
Distinct subsets of dendritic cells (DCs) are present in blood, probably "en route" to different tissues. We have investigated the chemokines and adhesion molecules involved in the migration of myeloid (CD11c(+)) and plasmacytoid (CD123(+)) human peripheral blood DCs across vascular endothelium. Among blood DCs, the CD11c(+) subset vigorously migrated across endothelium in the absence of any chemotactic stimuli, whereas spontaneous migration of CD123(+) DCs was limited. In bare cell migration assays, myeloid DCs responded with great potency to several inflammatory and homeostatic chemokines, whereas plasmacytoid DCs responded poorly to all chemokines tested. In contrast, the presence of endothelium greatly favored transmigration of plasmacytoid DCs in response to CXCL12 (stromal cell-derived factor-1) and CCL5 (regulated on activation, normal T expressed and secreted). Myeloid DCs exhibited a very potent transendothelial migration in response to CXCL12, CCL5, and CCL2 (monocyte chemoattractant protein-1). Furthermore, we explored whether blood DCs acutely switch their pattern of migration to the lymph node-derived chemokine CCL21 (secondary lymphoid-tissue chemokine) in response to microbial stimuli [viral double-stranded (ds)RNA or bacterial CpG-DNA]. A synthetic dsRNA rapidly enhanced the response of CD11c(+) DCs to CCL21, whereas a longer stimulation with CpG-DNA was needed to trigger CD123(+) DCs responsive to CCL21. Use of blocking monoclonal antibodies to adhesion molecules revealed that both DC subsets used platelet endothelial cell adhesion molecule-1 to move across activated endothelium. CD123(+) DCs required beta(2) and beta(1) integrins to transmigrate, whereas CD11c(+) DCs may use integrin-independent mechanisms to migrate across activated endothelium.  相似文献   
6.
Antibiotic prophylaxis in surgery is one of the most effective measures for preventing surgical site infection, although its use is frequently inadequate and may even increase the risk of infection, toxicities and antimicrobial resistance. As a result of advances in surgical techniques and the emergence of multidrug-resistant organisms, the current guidelines for prophylaxis need to be revised.The Sociedad Española de Enfermedades Infecciosas (Spanish Society of Infectious Diseases and Clinical Microbiology) (SEIMC) together with the Asociación Española de Cirujanos (Spanish Association of Surgeons) (AEC) have revised and updated the recommendations for antibiotic prophylaxis in surgery to adapt them to any type of surgical intervention and to current epidemiology. This document gathers together the recommendations on antimicrobial prophylaxis in the various procedures, with doses, duration, prophylaxis in special patient groups, and in epidemiological settings of multidrug resistance to facilitate standardized management and the safe, effective and rational use of antibiotics in elective surgery.  相似文献   
7.

Objectives

This article has two main purposes. Firstly, to model the integrated healthcare expenditure for the entire population of a health district in Spain, according to multimorbidity, using Clinical Risk Groups (CRG). Secondly, to show how the predictive model is applied to the allocation of health budgets.

Methods

The database used contains the information of 156,811 inhabitants in a Valencian Community health district in 2013. The variables were: age, sex, CRG’s main health statuses, severity level, and healthcare expenditure. The two-part models were used for predicting healthcare expenditure. From the coefficients of the selected model, the relative weights of each group were calculated to set a case-mix in each health district.

Results

Models based on multimorbidity-related variables better explained integrated healthcare expenditure. In the first part of the two-part models, a logit model was used, while the positive costs were modelled with a log-linear OLS regression. An adjusted R2 of 46–49% between actual and predicted values was obtained. With the weights obtained by CRG, the differences found with the case-mix of each health district proved most useful for budgetary purposes.

Conclusions

The expenditure models allowed improved budget allocations between health districts by taking into account morbidity, as opposed to budgeting based solely on population size.  相似文献   
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10.
Chronic nicotine exposure (CNE) alters synaptic transmission in the ventral tegmental area (VTA) in a manner that enhances dopaminergic signaling and promotes nicotine use. The present experiments identify a correlation between enhanced production of the endogenous cannabinoid 2-arachidonoylglycerol (2-AG) and diminished release of the inhibitory neurotransmitter GABA in the VTA following CNE. To study the functional role of on-demand 2-AG signaling in GABAergic synapses, we used 1,2,3-triazole urea compounds to selectively inhibit 2-AG biosynthesis by diacylglycerol lipase (DAGL). The potency and selectivity of these inhibitors were established in rats in vitro (rat brain proteome), ex vivo (brain slices), and in vivo (intracerebroventricular administration) using activity-based protein profiling and targeted metabolomics analyses. Inhibition of DAGL (2-AG biosynthesis) rescues nicotine-induced VTA GABA signaling following CNE. Conversely, enhancement of 2-AG signaling in naïve rats by inhibiting 2-AG degradation recapitulates the loss of nicotine-induced GABA signaling evident following CNE. DAGL inhibition reduces nicotine self-administration without disrupting operant responding for a nondrug reinforcer or motor activity. Collectively, these findings provide a detailed characterization of selective inhibitors of rat brain DAGL and demonstrate that excessive 2-AG signaling contributes to a loss of inhibitory GABAergic constraint of VTA excitability following CNE.The mesocorticolimbic dopamine (DA) system provides a critical link between the brain regions that process cognitive information and those controlling motor behavior. Precise control of these ventral tegmental area (VTA) projections facilitates seeking rewarding stimuli, retreating from aversive stimuli, constraint of motivational state, and behavioral flexibility necessary for survival. GABAergic signaling provides robust inhibition that gates VTA DA cell excitability (1, 2), and loss of this inhibition leads to pathological dysregulation of mesocorticolimbic circuitry (3, 4).Endocannabinoids (eCBs) regulate DAergic activity through retrograde signaling from DA cell bodies onto presynaptic cannabinoid type 1 (CB1) receptors expressed on both inhibitory and excitatory inputs. Although both 2-arachidonoylglycerol (2-AG) and anandamide (AEA) function as endogenous CB1 agonists in the brain (57), these lipids exhibit distinct pharmacological profiles in vivo (8, 9) and mediate differential behavioral effects (10, 11). Endocannabinoids are produced and degraded on-demand, and the primary enzymes responsible for eCB degradation have been well-characterized using selective pharmacological tools that inactivate monoacylglycerol lipase (MAGL) or fatty acid amide hydrolase (FAAH) (1113). However, a complete evaluation of the influence of eCB signaling in the brain has been hampered by the lack of appropriate corresponding tools for selectively inactivating on-demand eCB biosynthesis.Substantial evidence implicates eCB signaling in the etiology of nicotine addiction, and recent work demonstrates that chronic nicotine exposure (CNE) selectively enhances nicotine-induced increases in VTA 2-AG formation (14). The present study investigated the possible contribution of this effect to aberrant VTA DA cell excitation present following CNE (15). We find that sensitized nicotine-induced 2-AG release (14) strongly correlates with a loss of nicotine-induced GABA release, which may contribute to impaired inhibitory constraint of VTA DA cell excitation following CNE. To test this hypothesis, we characterized a series of selective inhibitors of 2-AG biosynthesis by diacylglycerol lipase α and β (DAGLα and DAGLβ; hereafter referred to as DAGL) (1618) and 2-AG degradation by α/β-hydrolase domain 6 (ABHD6) and MAGL (11, 12, 19), and used these compounds to investigate the functional impact of enhanced 2-AG recruitment on GABAergic signaling at VTA synapses and nicotine self-administration.  相似文献   
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