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121.
This paper reports the study of new 2-phenyl- and 2-methylpyrazolo[3,4-c]quinolin-4-ones (series A) and 4-amines (series B), designed as adenosine receptor (AR) antagonists. The synthesized compounds bear at the 6-position various groups, with different lipophilicity and steric hindrance, that were thought to increase human A(1) and A(2A) AR affinities and selectivities, with respect to those of the parent 6-unsubstituted compounds. In series A, this modification was not tolerated since it reduced AR affinity, while in series B it shifted the binding towards the hA(1) subtype. To rationalize the observed structure-affinity relationships, molecular docking studies at A(2A)AR-based homology models of the A(1) and A(3) ARs and at the A(2A)AR crystal structure were carried out.  相似文献   
122.

Background

Acute respiratory failure (ARF) and severe sepsis (SS) are possible complications in patients with community-acquired pneumonia (CAP). The aim of the study was to evaluate prevalence, characteristics, risk factors and impact on mortality of hospitalized patients with CAP according to the presence of ARF and SS on admission.

Methods

This was a multicenter, observational, prospective study of consecutive CAP patients admitted to three hospitals in Italy, Spain, and Scotland between 2008 and 2010. Three groups of patients were identified: those with neither ARF nor SS (Group A), those with only ARF (Group B) and those with both ARF and SS (Group C) on admission.

Results

Among the 2,145 patients enrolled, 45% belonged to Group A, 36% to Group B and 20% to Group C. Patients in Group C were more severe than patients in Group B. Isolated ARF was correlated with age (p < 0.001), COPD (p < 0.001) and multilobar infiltrates (p < 0.001). The contemporary occurrence of ARF and SS was associated with age (p = 0.002), residency in nursing home (p = 0.007), COPD (p < 0.001), multilobar involvement (p < 0.001) and renal disease (p < 0.001). 4.2% of patients in Group A died, 9.3% in Group B and 26% in Group C, p < 0.001. After adjustment, the presence of only ARF had an OR for in-hospital mortality of 1.85 (p = 0.011) and the presence of both ARF and SS had an OR of 6.32 (p < 0.001).

Conclusions

The identification of ARF and SS on hospital admission can help physicians in classifying CAP patients into three different clinical phenotypes.  相似文献   
123.

Introduction

Treatment failure in community-acquired-pneumonia (CAP) patients is associated with a high mortality rate, and therefore are a matter of great concern in clinical management. Those patients have increased mortality and are a target population for randomized clinical trials.

Methods

A case–control study was performed in patients with CAP (non-failure cases vs. failure cases, discriminating by late and early failure). CRP, PCT, interleukin 1, 6, 8 and 10 and TNF were determined at days 1 and 3 of hospitalization.

Results

A total of 253 patients were included in this study where 83 patients presented treatment failure. Of these, 40 (48.2%) had early failure. A discriminative effect was found for a higher CURB-65 score among late failure patients (p = 0.004). A significant increase on day 1 of hospitalization in CRP (p < 0.001), PCT (p = 0.004), IL-6 (p < 0.001) and IL-8 (p = 0.02), and a decrease in IL-1 (p = 0.06) in patients with failure was observed compared with patients without failure. On day 3, only the increase in CRP (p < 0.001), PCT (p = 0.007) and IL-6 (p < 0.001) remained significant. Independent predictors for early failure were higher IL-6 levels on day 1 (OR = 1.78, IC = 1.2-2.6) and pleural effusion (OR = 2.25, IC = 1.0-5.3), and for late failure, higher PCT levels on day 3 (OR = 1.60, IC = 1.0-2.5), CURB-65 score ≥ 3 (OR = 1.43, IC = 1.0-2.0), and multilobar involvement (OR = 4.50, IC = 2.1-9.9).

Conclusions

There was a good correlation of IL-6 levels and CAP failure and IL-6 & PCT with late CAP failure. Pleural effusion and multilobar involvement were simple clinical predictors of early and late failure, respectively.

Trial registration

IRB Register: http://2009/5451.  相似文献   
124.
Severe pneumonia remains an important cause of morbidity and mortality. Polymerase chain reaction (PCR) has been shown to be more sensitive than current standard microbiological methods – particularly in patients with prior antibiotic treatment – and therefore, may improve the accuracy of microbiological diagnosis for hospitalized patients with pneumonia. Conventional detection techniques and multiplex PCR for 14 typical bacterial pneumonia-associated pathogens were performed on respiratory samples collected from adult hospitalized patients enrolled in a prospective multi-center study. Patients were enrolled from March until September 2012. A total of 739 fresh, native samples were eligible for analysis, of which 75 were sputa, 421 aspirates, and 234 bronchial lavages. 276 pathogens were detected by microbiology for which a valid PCR result was generated (positive or negative detection result by Curetis prototype system). Among these, 120 were identified by the prototype assay, 50 pathogens were not detected. Overall performance of the prototype for pathogen identification was 70.6% sensitivity (95% confidence interval (CI) lower bound: 63.3%, upper bound: 76.9%) and 95.2% specificity (95% CI lower bound: 94.6%, upper bound: 95.7%). Based on the study results, device cut-off settings were adjusted for future series production. The overall performance with the settings of the CE series production devices was 78.7% sensitivity (95% CI lower bound: 72.1%) and 96.6% specificity (95% CI lower bound: 96.1%). Time to result was 5.2 hours (median) for the prototype test and 43.5 h for standard-of-care. The Pneumonia Application provides a rapid and moderately sensitive assay for the detection of pneumonia-causing pathogens with minimal hands-on time.

Trial Registration

Deutsches Register Klinischer Studien (DRKS) DRKS00005684  相似文献   
125.
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127.
PGE(2) is involved in a wide variety of physiological and pathological processes; however, deciphering its role in early mammalian development has been difficult due to the maternal contribution of PGE(2). To overcome this limitation we have investigated the role of PGE(2) during T cell development in zebrafish. In this study, we show that zebrafish ep4a, a PGE(2) receptor isoform of EP4, is expressed at 26 h postfertilization in the dorsal aorta-posterior cardinal vein joint region, which has a high homology with the mammal aorta-gonad-mesonephros area and where definitive hemopoiesis arises. Furthermore, it is expressed in the presumptive thymus rudiment by 48 h postfertilization. Supplementation of PGE(2) results in a strong increase in rag1 levels and cell proliferation in the thymus. In contrast, the inhibition of PGE(2) production, as well as EP4 blockade, abrogates the expression of rag1 in the thymus and that of the lymphoid precursor marker ikaros, not only in the dorsal aorta-posterior cardinal vein joint region but also in the newly identified caudal hemopoietic tissue without affecting early hemopoietic (scl, gata2) and erythropoietic (gata1) markers. These results identify ep4a as the earliest thymus marker and define a novel role for the PGE(2)/EP4 pathway in controlling T cell precursor development in zebrafish.  相似文献   
128.
The discovery of new drugs for the treatment of neurodegenerative disorders, such as Parkinson's disease, has become an attractive field of research. Due to the regulation of D(2) receptor activity by A(2A) adenosine receptor, potent and selective ligands of A(2A) subtype could be useful tools to study neurodegenerative disorders. A series of 2,8-disubstituted-9-ethyladenine derivatives was synthesized and tested in binding affinity assay at human adenosine receptors. New compounds showed good affinity and selectivity at A(2A) receptor versus the other subtypes. The introduction of a bromine atom in 8-position increased the affinity of these compounds, leading to ligands with K(i) in the nanomolar range.  相似文献   
129.
Purpose

Energy consumption of buildings is one of the major drivers of environmental impacts. Life cycle assessment (LCA) may support the assessment of burdens and benefits associated to eco-innovations aiming at reducing these environmental impacts. Energy efficiency policies however typically focus on the meso- or macro-scale, while interventions are typically taken at the micro-scale. This paper presents an approach that bridges this gap by using the results of energy simulations and LCA studies at the building level to estimate the effect of micro-scale eco-innovations on the macro-scale, i.e. the housing stock in Europe.

Methods

LCA and dynamic energy simulations are integrated to accurately assess the life cycle environmental burdens and benefits of eco-innovation measures at the building level. This allows quantitatively assessing the effectiveness of these measures to lower the energy use and environmental impact of buildings. The analysis at this micro-scale focuses on 24 representative residential buildings within the EU. For the upscaling to the EU housing stock, a hybrid approach is used. The results of the micro-scale analysis are upscaled to the EU housing stock scale by adopting the eco-innovation measures to (part of) the EU building stock (bottom–up approach) and extrapolating the relative impact reduction obtained for the reference buildings to the baseline stock model. The reference buildings in the baseline stock model have been developed by European Commission-Joint Research Centre based on a statistical analysis (top–down approach) of the European housing stock. The method is used to evaluate five scenarios covering various aspects: building components (building envelope insulation), technical installations (renewable energy), user behaviour (night setback of the setpoint temperature), and a combined scenario.

Results and discussion

Results show that the proposed combination of bottom–up and top–down approaches allow accurately assessing the impact of eco-innovation measures at the macro-scale. The results indicate that a combination of policy measures is necessary to lower the environmental impacts of the building stock to a significative extent.

Conclusions

Interventions addressing energy efficiency at building level may lead to the need of a trade-off between resource efficiency and environmental impacts. LCA integrated with dynamic energy simulation may help unveiling the potential improvements and burdens associated to eco-innovations.

  相似文献   
130.
Cytomegalovirus (CMV) is a highly species-specific virus that has co-evolved with its host over millions of years and thus restricting cross-species infection. To examine the extent to which host restriction may prevent cross-species research between closely related non-human primates, we evaluated experimental infection of cynomolgus macaques with a recombinant rhesus macaque-derived CMV (RhCMV-eGFP). Twelve cynomolgus macaques were randomly allocated to three groups: one experimental group (RhCMV-eGFP) and two control groups (UV-inactivated RhCMV-eGFP or media alone). The animals were given two subcutaneous inoculations at week 0 and week 8, and a subset of animals received an intravenous inoculation at week 23. No overt clinical or haematological changes were observed and PBMCs isolated from RhCMV-eGFP inoculated animals had comparable eGFP- and IE-1-specific cellular responses to the control animals. Following inoculation with RhCMV-eGFP, we were unable to detect evidence of infection in any blood or tissue samples up to 4 years post-inoculation, using sensitive viral co-culture, qPCR, and Western blot assays. Co-culture of urine and saliva samples demonstrated the presence of endogenous cynomolgus CMV (CyCMV) cytopathic effect, however no concomitant eGFP expression was observed. The absence of detectable RhCMV-eGFP suggests that the CyCMV-seropositive cynomolgus macaques were not productively infected with RhCMV-eGFP under these inoculation conditions. In a continued effort to develop CMV as a viral vector for an HIV/SIV vaccine, these studies demonstrate that CMV is highly restricted to its host species and can be highly affected by laboratory cell culture. Consideration of the differences between lab-adapted and primary viruses with respect to species range and cell tropism should be a priority in evaluating CMV as vaccine vector for HIV or other pathogens at the preclinical development stage.  相似文献   
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