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101.
Functional magnetic resonance imaging (fMRI) was used to map hippocampal activation during a declarative memory task in a sample of 14 adolescents with antecedents of prematurity (AP). The sample with AP was matched by age, sex and handedness with 14 full-term controls with no history of neurological or psychiatric illness. The target task consisted in learning 16 novel face-name pairs, and the control task involved the examination of two repeated face-name pairs. Stereological methods were also used to quantify hippocampal volumes. In both groups, we observed increased activation in the learning condition compared to the control task in the right fusiform gyrus and the left inferior occipital gyrus, but only premature subjects activated the hippocampus. Group comparison of the activation versus control conditions showed that prematures had greater activity in the right hippocampus than controls during the encoding of the word-face association. Volumetric analyses showed a significant left hippocampal volume loss in adolescents with AP. In addition, we found a significant positive correlation in the premature group between right hippocampal activation and face-name recognition. Functional MRI data also correlated with structural MRI data: right hippocampal activation correlated positively with right hippocampal volume. Our findings are consistent with previous studies of brain plasticity after focal lesions. Left hippocampal tissue loss may be related to an increase in contralateral brain activity, probably reflecting a compensatory mechanism. Our data also suggest that this plasticity is not enough to achieve normal performance.  相似文献   
102.
103.
Aging‐related tau astrogliopathy (ARTAG) is defined by the presence of two types of tau‐bearing astrocytes: thorn‐shaped astrocytes (TSAs) and granular/fuzzy astrocytes in the brain of old‐aged individuals. The present study is focused on TSAs in rare forms of ARTAG with no neuronal tau pathology or restricted to entorhinal and transentorhinal cortices, to avoid bias from associated tauopathies. TSAs show 4Rtau phosphorylation at several specific sites and abnormal tau conformation, but they lack ubiquitin and they are not immunostained with tau‐C3 antibodies which recognize truncated tau at Asp421. Astrocytes in ARTAG have atrophic processes, reduced glial fibrillary acidic protein (GFAP) and increased superoxide dismutase 2 (SOD2) immunoreactivity. Gel electrophoresis and western blotting of sarkosyl‐insoluble fractions reveal a pattern of phospho‐tau in ARTAG characterized by two bands of 68 and 64 kDa, and several middle bands between 35 and 50 kDa which differ from what is seen in AD. Phosphoproteomics of dissected vulnerable regions identifies an increase of phosphorylation marks in a large number of proteins in ARTAG compared with controls. GFAP, aquaporin 4, several serine‐threonine kinases, microtubule associated proteins and other neuronal proteins are among the differentially phosphorylated proteins in ARTAG thus suggesting a hyper‐phosphorylation background that affects several molecules, including many kinases and proteins from several cell compartments and various cell types. Finally, present results show for the first time that tau seeding is produced in neurons of the hippocampal complex, astrocytes, oligodendroglia and along fibers of the corpus callosum, fimbria and fornix following inoculation into the hippocampus of wild type mice of sarkosyl‐insoluble fractions enriched in hyper‐phosphorylated tau from selected ARTAG cases. These findings show astrocytes as crucial players of tau seeding in tauopathies.  相似文献   
104.
Contact sensitivity (CS) is an inflammatory disorder characterized by early and late phases of leukocyte recruitment. We used a noninvasive intravital microscopy technique allowing for the direct visualization of leukocyte rolling and adhesion on blood vessel endothelium. By blocking specific adhesion molecules, we elucidated the molecular mechanisms mediating early leukocyte recruitment to be E- and P-selectin and demonstrated that leukocyte recruitment in the late phase had a different adhesive profile (mainly alpha(4)-integrin). Complete blockade of E- and P-selectin within the first 2 h of leukocyte-endothelial cell interactions (but not later) eliminated selectin-independent leukocyte recruitment at 24 h. Despite the predominance of neutrophils in the early phase, specific elimination of CD4(+) lymphocytes in the early phase eliminated the late response. CD4(+) lymphocytes homed to skin via E- and P-selectin within the early phase and induced the late phase response. Addition of these same CD4(+) lymphocytes 2 h after antigen challenge was too late for these cells to home to the skin and induce late phase responses. Our data clearly demonstrate that the antigen-challenged microenvironment is only accessible to CD4(+) lymphocytes for the first 2 h, and that this process is essential for the subsequent recruitment of other leukocyte populations in late phase responses.  相似文献   
105.

Introduction

Vital signs indicate the presence of bleeding only after large amounts of blood have been lost, with high morbidity and mortality. The Shock Index (SI) is a hemorrhage indicator with a cut-off point for the risk of bleeding at 0.9. The aim of this study is to assess whether a cut-off of  0.8 is more sensitive for detecting occult bleeding, providing for early initiation of therapeutic maneuvers.

Methods

SI analytical validation study of severe trauma patients older than 16 years of age. Vital signs were recorded, and scales for predicting bleeding included: SI, Assessment of Blood Consumption score, and Pulse Rate Over Pressure score. The relationship between the SI and 5 markers for bleeding was analyzed: need for massive transfusion, angiographic embolization, surgical bleeding control, death due to hypovolemic shock, and the overall predictor «active bleeding» (defined as the presence of at least one of the 4 markers above).

Results

Data from 1.402 trauma patients were collected prospectively over a period of 10 years. The mean Injury Severity Score was 20.9 (SD 15.8). The mortality rate was 10%. The mean SI was 0.73 (SD 0.29). «Active bleeding» was present in 18.7% of patients. The SI area under the ROC curve for «active bleeding» was 0.749.

Conclusions

An SI cut-off point  0.8 is more sensitive than  0.9 and allows for earlier initiation of resuscitation maneuvers in patients with occult active bleeding.  相似文献   
106.
This paper describes the use of focus groups as part of the evaluation of programmes to control food allergy and intolerance (FAI) in school settings in the city of Barcelona (Spain). After fostering their adoption and as a qualitative component of their evaluation, the public health services ran two focus groups, one with people from schools that manage their own kitchen, and another from companies that outsource this service. There were 28 participants from 46% of the centres invited. All the schools seem to have implemented a self-control programme on FAI. Although outsourcing companies already had a programme, the schools that managed their own service mostly adopted the programme promoted by the public health services. The number of schoolchildren with reported FAI reduced after the programme, as it required more rigorous documentation from families.  相似文献   
107.
108.
ObjectiveThe objective of the study was to know the profile of patients diagnosed with chronic obstructive pulmonary disease (COPD) and who have never been smokers.DesignA transversal study.LocationPrimary Care Centre of Pla d’Urgell (Primary care setting in Lleida, Spain).Participants512 patients older than 40 years with COPD from Primary Care Centre of Pla d’Urgell with a compatible spirometry [forced expiratory volume in one second (FEV1)/forced vital capacity (FVC) ratio < 0.7) to the beginning of the study.Main measurementsThe dependent variable was de COPD in non-smokers and the independents were variables collected from the information on the respiratory clinical history, the risk factors of the patients and on quality of life. We designed a predictor model of COPD in non-smokers compared to smokers.Results33.2% of COPD patients had never been smokers, 59.4% of whom were women. The average FEV1 for non-smokers was 70.5 (SD = 17.1), higher than 62.6 (SD = 18.5) for smokers/former smokers (p < 0.001). The coverage of pneumococcal vaccination 23V was better in non-smokers (75.3%), p < 0.001. COPD in non-smokers (compared to smokers/former smokers) were: mostly women (OR = 16.46), older (OR = 1.1), with better FEV1 (OR = 1.1), better perception of quality, EuroQoL-5D (OR = 0.8), with lower prevalence of diabetes (OR = 0.5), lower level of studies (OR = 0.2), and with fewer previous hospitalizations (OR = 0.3).ConclusionsThe study evidences a high proportion of non-smokers in COPD patients. Our study aims that older women with less severity would be associated with an increased risk of COPD in non-smokers. It seems to indicate that COPD in non-smokers would appear at later ages and would be milder than smoking-related COPD.  相似文献   
109.
110.
Breakthrough pain (BKP) is a transitory flare of pain that occurs on a background of relatively well controlled baseline pain. Previous surveys have found that BKP is highly prevalent among patients with cancer pain and predicts more severe pain, pain-related distress and functional impairment, and relatively poor quality of life. An international group of investigators assembled by a task force of the International Association for the Study of Pain (IASP) evaluated the prevalence and characteristics of BKP as part of a prospective, cross-sectional survey of cancer pain. Fifty-eight clinicians in 24 countries evaluated a total of 1095 patients with cancer pain using patient-rated items from the Brief Pain Inventory (BPI) and observer-rated measures. The observer-rated information included demographic and tumor-related data, the occurrence of BKP, and responses on checklists of pain syndromes and pathophysiologies. The clinicians reported BKP in 64.8% of patients. Physicians from English-speaking countries were significantly more likely to report BKP than other physicians. BKP was associated with higher pain scores and functional interference on the BPI. Multivariate analysis showed an independent association of BKP with the presence of more than one pain, a vertebral pain syndrome, pain due to plexopathy, and English-speaking country. These data confirm the high prevalence of BKP, its association with more severe pain and functional impairment, and its relationship to specific cancer pain syndromes. Further studies are needed to characterize subtypes of BKP. The uneven distribution of BKP reporting across pain specialists from different countries suggests that more standardized methods for diagnosing BKP are needed.  相似文献   
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