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911.
912.

Background

Perinatal asphyxia (PA) is a leading cause of mortality and morbidity in newborns: its prognosis depends both on the severity of the asphyxia and on the immediate resuscitation to restore oxygen supply and blood circulation. Therefore, we investigated whether measurement of S100B, a consolidated marker of brain injury, in salivary fluid of PA newborns may constitute a useful tool for the early detection of asphyxia-related brain injury.

Methods

We conducted a cross-sectional study in 292 full-term newborns admitted to our NICUs, of whom 48 suffered PA and 244 healthy controls admitted at our NICUs. Saliva S100B levels measurement longitudinally after birth; routine laboratory variables, neurological patterns, cerebral ultrasound and, magnetic resonance imaging were performed. The primary end-point was the presence of neurological abnormalities at 12-months after birth.

Results

S100B salivary levels were significantly (P<0.001) higher in newborns with PA than in normal infants. When asphyxiated infants were subdivided according to a good (Group A; n = 15) or poor (Group B; n = 33) neurological outcome at 12-months, S100B was significantly higher at all monitoring time-points in Group B than in Group A or controls (P<0.001, for all). A cut-off >3.25 MoM S100B achieved a sensitivity of 100% (CI5-95%: 89.3%-100%) and a specificity of 100% (CI5-95%: 98.6%-100%) as a single marker for predicting the occurrence of abnormal neurological outcome (area under the ROC curve: 1.000; CI5-95%: 0.987-1.0).

Conclusions

S100B protein measurement in saliva, soon after birth, is a useful tool to identify which asphyxiated infants are at risk of neurological sequelae.  相似文献   
913.

Background

New evidence shows that high density lipoproteins (HDL) have protective effects beyond their role in reverse cholesterol transport. Reconstituted HDL (rHDL) offer an attractive means of clinically exploiting these novel effects including cardioprotection against ischemia reperfusion injury (IRI). However, basic rHDL composition is limited to apolipoprotein AI (apoAI) and phospholipids; addition of bioactive compound may enhance its beneficial effects.

Objective

The aim of this study was to investigate the role of rHDL in post-ischemic model, and to analyze the potential impact of sphingosine-1-phosphate (S1P) in rHDL formulations.

Methods and Results

The impact of HDL on IRI was investigated using complementary in vivo, ex vivo and in vitro IRI models. Acute post-ischemic treatment with native HDL significantly reduced infarct size and cell death in the ex vivo, isolated heart (Langendorff) model and the in vivo model (-48%, p<0.01). Treatment with rHDL of basic formulation (apoAI + phospholipids) had a non-significant impact on cell death in vitro and on the infarct size ex vivo and in vivo. In contrast, rHDL containing S1P had a highly significant, protective influence ex vivo, and in vivo (-50%, p<0.01). This impact was comparable with the effects observed with native HDL. Pro-survival signaling proteins, Akt, STAT3 and ERK1/2 were similarly activated by HDL and rHDL containing S1P both in vitro (isolated cardiomyocytes) and in vivo.

Conclusion

HDL afford protection against IRI in a clinically relevant model (post-ischemia). rHDL is significantly protective if supplemented with S1P. The protective impact of HDL appears to target directly the cardiomyocyte.  相似文献   
914.

Introduction

The default mode network and the working memory network are known to be anti-correlated during sustained cognitive processing, in a load-dependent manner. We hypothesized that functional connectivity among nodes of the two networks could be dynamically modulated by task phases across time.

Methods

To address the dynamic links between default mode network and the working memory network, we used a delayed visuo-spatial working memory paradigm, which allowed us to separate three different phases of working memory (encoding, maintenance, and retrieval), and analyzed the functional connectivity during each phase within and between the default mode network and the working memory network networks.

Results

We found that the two networks are anti-correlated only during the maintenance phase of working memory, i.e. when attention is focused on a memorized stimulus in the absence of external input. Conversely, during the encoding and retrieval phases, when the external stimulation is present, the default mode network is positively coupled with the working memory network, suggesting the existence of a dynamically switching of functional connectivity between “task-positive” and “task-negative” brain networks.

Conclusions

Our results demonstrate that the well-established dichotomy of the human brain (anti-correlated networks during rest and balanced activation-deactivation during cognition) has a more nuanced organization than previously thought and engages in different patterns of correlation and anti-correlation during specific sub-phases of a cognitive task. This nuanced organization reinforces the hypothesis of a direct involvement of the default mode network in cognitive functions, as represented by a dynamic rather than static interaction with specific task-positive networks, such as the working memory network.  相似文献   
915.
Stachys annua subsp. annua, well‐known in central Italy as ‘stregona annuale’, is an annual, small, slightly‐scented herb, commonly found in fields and uncultivated areas in almost all regions of Italy. In folk medicine, its aerial parts were used as anti‐catarrhal, febrifuge, tonic, and vulnerary. In the present work, the chemical composition of the flowering aerial parts was studied. The hydrodistilled volatile oil, analysed by GC/MS, showed sesquiterpenoids as the major fraction (42.5%); phytol (9.8%), germacrene D (9.2%), and spathulenol (8.5%) were the most abundant constituents. The volatile oil was assayed for antioxidant and cytotoxic activity by DPPH, ABTS, FRAP, and MTT methods. The cytotoxicity results against HCT116, A375, and MDA‐MB 231 human tumor cell lines were significant, with IC50 values of 23.5, 37.2, and 41.5 μg/ml, respectively, whereas the antioxidant power was negligible. The EtOH extract was composed mainly of three glycosidic flavonoids, namely 7‐{[2‐O‐(6‐O‐acetyl‐β‐D ‐allopyranosyl)‐β‐D ‐glucopyranosyl]oxy}‐5,8‐dihydroxy‐2‐(4‐methoxyphenyl)‐4H‐1‐benzopyran‐4‐one ( 1 ), 7‐{[6‐O‐acetyl‐2‐O‐(6‐O‐acetyl‐β‐D ‐allopyranosyl)‐β‐D ‐glucopyranosyl]oxy}‐2‐(3,4‐dihydroxyphenyl)‐5,8‐dihydroxy‐4H‐1‐benzopyran‐4‐one ( 2 ), and 7‐{[6‐O‐acetyl‐2‐O‐(β‐D ‐allopyranosyl)‐β‐D ‐glucopyranosyl]oxy}‐2‐(3‐hydroxy‐4‐methoxyphenyl)‐5,8‐dihydroxy‐4H‐1‐benzopyran‐4‐one ( 3 ). On the contrary, iridoids, considered chemotaxonomic markers of the genus Stachys, were absent in this species. Finally, the morphological and histochemical survey showed that glandular trichomes were composed of two main types, i.e. peltate type A and capitate types B and C giving positive response for both lipids and polyphenols.  相似文献   
916.

Background/Aim

We present a clinical-neuroimaging study in a series of patients with a clinical diagnosis of semantic variant of primary progressive aphasia (svPPA), with the aim to provide clinical-functional correlations of the cognitive and behavioral manifestations at the single-subject level.

Methods

We performed neuropsychological investigations, 18F-FDG-PET single-subject and group analysis, with an optimized SPM voxel-based approach, and correlation analyses. A measurement of white matter integrity by means of diffusion tensor imaging (DTI) was also available for a subgroup of patients.

Results

Cognitive assessment confirmed the presence of typical semantic memory deficits in all patients, with a relative sparing of executive, attentional, visuo-constructional, and episodic memory domains. 18F-FDG-PET showed a consistent pattern of cerebral hypometabolism across all patients, which correlated with performance in semantic memory tasks. In addition, a majority of patients also presented with behavioral disturbances associated with metabolic dysfunction in limbic structures. In a subgroup of cases the DTI analysis showed FA abnormalities in the inferior longitudinal and uncinate fasciculi.

Discussion

Each svPPA individual had functional derangement involving an extended, connected system within the left temporal lobe, a crucial part of the verbal semantic network, as well as an involvement of limbic structures. The latter was associated with behavioral manifestations and extended beyond the area of atrophy shown by CT scan.

Conclusion

Single-subject 18F-FDG-PET analysis can account for both cognitive and behavioral alterations in svPPA. This provides useful support to the clinical diagnosis.  相似文献   
917.
Neurodegenerative process in amyotrophic lateral sclerosis (ALS) has been proven to involve several cortical and subcortical brain regions within and beyond motor areas. However, how ALS pathology spreads progressively during disease evolution is still unknown. In this cross-sectional study we investigated 54 ALS patients, divided into 3 subsets according to the clinical stage, and 18 age and sex-matched healthy controls, by using tract-based spatial statistics (TBSS) diffusion tensor imaging (DTI) and voxel-based morphometry (VBM) analyses. We aimed to identify white (WM) and gray matter (GM) patterns of disease distinctive of each clinical stage, corresponding to specific clinical milestones. ALS cases in stage 2A (i.e., at diagnosis) were characterized by GM and WM impairment of left motor and premotor cortices and brainstem at ponto-mesenchephalic junction. ALS patients in clinical stage 2B (with impairment of two functional regions) exhibited decreased fractional anisotropy (FA) (p<0.001, uncorrected) and increased mean (MD) and radial diffusivity (RD) (p<0.001, uncorrected) in the left cerebellar hemisphere and brainstem precerebellar nuclei, as well as in motor areas, while GM atrophy (p<0.001, uncorrected) was detected only in the left inferior frontal gyrus and right cuneus. Finally, ALS patients in stage 3 (with impairment of three functional regions) exhibited decreased FA and increased MD and RD (p<0.05, corrected) within WM underneath bilateral pre and postcentral gyri, corpus callosum midbody, long associative tracts and midbrain, while no significant clusters of GM atrophy were observed. Our findings reinforce the hypothesis that the neurodegenerative process propagates along the axonal pathways and develops beyond motor areas from early stages, involving progressively several frontotemporal regions and their afferents and efferents, while the detection of GM atrophy in earlier stages and its disappearance in later stages may be the result of reactive gliosis.  相似文献   
918.

Background

The duration of antibiotic treatment of exacerbations of COPD (ECOPD) is controversial. Serum procalcitonin (PCT) is a biomarker of bacterial infection used to identify the cause of ECOPD.

Methods and Findings

We investigated whether a PCT-guided plan would allow a shorter duration of antibiotic treatment in patients with severe ECOPD. For this multicenter, randomized, non-inferiority trial, we enrolled 184 patients hospitalized with ECOPD from 18 hospitals in Italy. Patients were assigned to receive antibiotics for 10 days (standard group) or for either 3 or 10 days (PCT group). The primary outcome was the rate of ECOPD at 6 months. Having planned to recruit 400 patients, we randomized only 183: 93 in the PCT group and 90 in the standard group. Thus, the completed study was underpowered. The ECOPD rate at 6 months between PCT-guided and standard antibiotic treatment was not significant (% difference, 4.04; 90% confidence interval [CI], −7.23 to 15.31), but the CI included the non-inferiority margin of 15. In the PCT-guided group, about 50% of patients were treated for 3 days, and there was no difference in primary or secondary outcomes compared to patients treated for 10 days.

Conclusions

Although the primary and secondary clinical outcomes were no different for patients treated for 3 or 10 days in the PCT group, the conclusion that antibiotics can be safely stopped after 3 days in patients with low serum PCT cannot be substantiated statistically. Thus, the results of this study are inconclusive regarding the noninferiority of the PCT-guided plan compared to the standard antibiotic treatment. The study was funded by Agenzia Italiana del Farmaco (AIFA-FARM58J2XH). Clinical trial registered with www.clinicaltrials.gov (NCT01125098).

Trial Registration

ClinicalTrials.gov NCT01125098  相似文献   
919.
The Protein Tyrosine Phosphatase (PTP) family comprises a large and diverse group of enzymes, regulating a range of biological processes through de-phosphorylation of many proteins and lipids. These enzymes share a catalytic mechanism that requires a reduced and reactive cysteine nucleophile, making them potentially sensitive to inactivation and regulation by oxidation. Analysis of ten PTPs identified substantial differences in the sensitivity of these enzymes to oxidation in vitro. More detailed experiments confirmed the following rank order of sensitivity: PTEN and Sac1>PTPL1/FAP-1>myotubularins. When the apparent sensitivity to oxidation of these PTPs in cells treated with hydrogen peroxide was analysed, this correlated well with the observed sensitivities to oxidation in vitro. These data suggested that different PTPs may fall into at least three different classes with respect to mechanisms of cellular redox regulation. 1. PTEN and Sac1 were readily and reversibly oxidised in vitro and in cells treated with hydrogen peroxide 2. PTPL1 appeared to be resistant to oxidation in cells, correlating with its sensitivity to reduction by glutathione in vitro 3. The myotubularin family of lipid phosphatases was almost completely resistant to oxidation in vitro and in cells. Our results show that sensitivity to reversible oxidation is not a necessary characteristic of the PTPs and imply that such sensitivity has evolved as a regulatory mechanism for some of this large family, but not others.  相似文献   
920.
This study aims to establish the contribution of the water soluble and water insoluble organic fractions to total oxygen uptake rate during high rate composting process of a mixture of organic fraction of municipal solid waste and lignocellulosic material. This mixture was composted using a 20 l self-heating pilot scale composter for 250 h. The composter was fully equipped to record both the biomass-temperature and oxygen uptake rate. Representative compost samples were taken at 0, 70, 100, 110, 160, and 250 h from starting time. Compost samples were fractionated in water soluble and water insoluble fractions. The water soluble fraction was then fractionated in hydrophilic, hydrophobic, and neutral hydrophobic fractions. Each fraction was then studied using quantitative (total organic carbon) and qualitative analysis (diffuse reflectance infrared spectroscopy and biodegradability test). Oxygen uptake rates were high during the initial stages of the process due to rapid degradation of the soluble degradable organic fraction (hydrophilic plus hydrophobic fractions). Once this fraction was depleted, polymer hydrolysis accounted for most of the oxygen uptake rate. Finally, oxygen uptake rate could be modeled using a two term kinetic. The first term provides the oxygen uptake rate resulting from the microbial growth kinetic type on easily available, no-limiting substrate (soluble fraction), while the second term considers the oxygen uptake rate caused by the degradation of substrate produced by polymer hydrolysis.  相似文献   
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