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Celia P. Miralles Michael J. Taylor John Bear Jr. Christopher D. Fekete Shanu George Yanfang Li Bevan Bonhomme Tzu-Ting Chiou Angel L. De Blas 《The Journal of comparative neurology》2020,528(5):840-864
It has been proposed that the combinatorial expression of γ-protocadherins (Pcdh-γs) and other clustered protocadherins (Pcdhs) provides a code of molecular identity and individuality to neurons, which plays a major role in the establishment of specific synaptic connectivity and formation of neuronal circuits. Particular attention has been directed to the Pcdh-γ family, for which experimental evidence derived from Pcdh-γ-deficient mice shows that they are involved in dendrite self-avoidance, synapse development, dendritic arborization, spine maturation, and prevention of apoptosis of some neurons. Moreover, a triple-mutant mouse deficient in the three C-type members of the Pcdh-γ family (Pcdh-γC3, Pcdh-γC4, and Pcdh-γC5) shows a phenotype similar to the mouse deficient in whole Pcdh-γ family, indicating that the latter is largely due to the absence of C-type Pcdh-γs. The role of each individual C-type Pcdh-γ is not known. We have developed a specific antibody to Pcdh-γC4 to reveal the expression of this protein in the rat brain. The results show that although Pcdh-γC4 is expressed at higher levels in the embryo and earlier postnatal weeks, it is also expressed in the adult rat brain. Pcdh-γC4 is expressed in both neurons and astrocytes. In the adult brain, the regional distribution of Pcdh-γC4 immunoreactivity is similar to that of Pcdh-γC4 mRNA, being highest in the olfactory bulb, dentate gyrus, and cerebellum. Pcdh-γC4 forms puncta that are frequently apposed to glutamatergic and GABAergic synapses. They are also frequently associated with neuron-astrocyte contacts. The results provide new insights into the cell recognition function of Pcdh-γC4 in neurons and astrocytes. 相似文献
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Sarah Heili Frades María del Pilar Carballosa de Miguel Alba Naya Prieto Marina Galdeano Lozano Xavier Mate García Ignacio Mahillo Fernández Itziar Fernández Ormaechea Laura Álvarez Suárez Farah Ezzine de Blas María José Checa Venegas Nicolás González Mangado Germán Peces Barba 《Archivos de bronconeumologia》2019,55(12):634-641
IntroductionHistorically, it has been assumed that Intermediate Respiratory Care Units (IRCU) were efficient, because they saved costs by reducing the number of admissions to intensive care units (ICU), and effective, because they specialized in respiratory diseases.MethodsThe number of IRCU admissions and mortality rate, historically and in 2016, were evaluated. For 2016, the grouped Related Diagnostic Groups (DRGs) were also described, and the savings achieved under all budgetary headings by avoiding UCI stays were calculated. A multivariate analysis was performed to associate costs with mean weights and complexity, and multiple logistic regression was performed on all patients admitted from 2004 to 2017 to describe the variables associated with mortality in our unit.ResultsAn IRCU generates savings of €500,000/year by reducing length of ICU stay. Analysis of the 2016 cohort shows that costs correlate with mean weight and mortality, and consequently complexity. The multivariate logistic regression analysis of the 2004–2017 cohort found respiratory frequency, leukopenia, anemia, hyperkalemia, and acidosis to be the variables best associated with mortality. The area under the curve for the logistic model was 0.75.ConclusionThe IRCU analyzed in our study was efficient in terms of ‘avoided costs’ and savings associated with complexity. Our results suggest that IRCUs have a lower mortality rate than other similar units, and are therefore a safe environment for patients. 相似文献
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WH Brown MP Gillum HY Lee JP Camporez XM Zhang JK Jeong TC Alves DM Erion BA Guigni M Kahn VT Samuel BF Cravatt S Diano GI Shulman 《Proceedings of the National Academy of Sciences of the United States of America》2012,109(37):14966-14971
Fatty acid amide hydrolase (FAAH) knockout mice are prone to excess energy storage and adiposity, whereas mutations in FAAH are associated with obesity in humans. However, the molecular mechanism by which FAAH affects energy expenditure (EE) remains unknown. Here we show that reduced energy expenditure in FAAH(-/-) mice could be attributed to decreased circulating triiodothyronine and thyroxine concentrations secondary to reduced mRNA expression of both pituitary thyroid-stimulating hormone and hypothalamic thyrotropin-releasing hormone. These reductions in the hypothalamic-pituitary-thyroid axis were associated with activation of hypothalamic peroxisome proliferating-activated receptor γ (PPARγ), and increased hypothalamic deiodinase 2 expression. Infusion of NAEs (anandamide and palmitoylethanolamide) recapitulated increases in PPARγ-mediated decreases in EE. FAAH(-/-) mice were also prone to diet-induced hepatic insulin resistance, which could be attributed to increased hepatic diacylglycerol content and protein kinase Cε activation. Our data indicate that FAAH deletion, and the resulting increases in NAEs, predispose mice to ectopic lipid storage and hepatic insulin resistance by promoting centrally mediated hypothyroidism. 相似文献
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Agil A Durán R Barrero F Morales B Araúzo M Alba F Miranda MT Prieto I Ramírez M Vives F 《Journal of the neurological sciences》2006,240(1-2):31-36
Oxidative stress plays an important role in the pathogenesis of neurodegenerative diseases, such as Parkinson's disease (PD). There are several methods to measure oxidative stress, being lipid peroxidation (LPO) one of the most frequently used. Endogenous plasma LPO was determined by a spectrofluorimetric method in fifty two patients with sporadic PD and in forty controls. To know the maximum capacity of lipids to peroxidate, LPO was also measured after co-incubation with Fe2+/H2O2 (exogenous LPO). All PD patients were taken L-dopa and the effect of this treatment on LPO levels was additionally studied. Urine catecholamines and their main metabolites were also analyzed, and their possible correlation to LPO statistically studied. Endogenous plasma LPO levels were 33% higher in PD group than in control group (P<0.001). Exogenous plasma or oxidizability was also higher in PD patients compared to controls (20%, P<0.05). The intake of L-dopa was negatively dose-related to endogenous and exogenous plasma LPO. In conclusion, plasma of PD patients has elevated levels of LPO and also is more prone to peroxidation than that in the control group. The results also suggest an antioxidant effect of L-dopa. 相似文献
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Jos E. Pereira Luís M. Costa Antnio M. Cabrita Pedro A. Couto Vítor M. Filipe Luís G. Magalhes Michele Fornaro Federica Di Scipio Stefano Geuna Ana C. Maurício Artur S.P. Varejo 《Experimental neurology》2009,220(1):71-81
Currently, methylprednisolone sodium succinate (MPSS) is the standard treatment following acute spinal cord injury (SCI) as a consequence of the results obtained from the National Acute Spinal Cord Injury Studies. However, many have questioned the efficacy of MPSS because of its marginal effects. Additionally there has been criticism of both study design and statistical interpretation. The functional consequences of experimental SCI have been assessed in many ways. The purpose of this investigation was to determine the effects of MPSS vs. saline solution (SS) following moderate T10 contusion injury in rat. Functional recovery was evaluated using the 21-point Basso, Beattie and Bresnahan (BBB) locomotor recovery scale, the inclined plane, the beam walk, footprint analysis and the horizontal ladder. To optimize the precision and accuracy of functional results we examined the locomotion on a treadmill using three-dimensional (3D) analysis. Stereology was used to estimate the amount of damaged tissue. The results of the traditional functional methods showed that administration of the NASCIS dosage of MPSS following acute spinal cord contusion did not lead to any significant differences in the functional recovery of MPSS- vs. SS-treated animals. More importantly, the results of the 3D kinematic showed that the MPSS administration did not affect the flexion/extension of the hip, knee and ankle joints during the step cycle. Finally, stereological results revealed no statistically significant differences between the two experimental groups. Altogether, our results support data previously reported by several authors, suggesting that MPSS does not lead to improved functional outcome following experimental acute SCI. 相似文献
50.
Sol Esteves Diana Andrea Ramirez Romero Teresa Torralva Macarena Martínez Cuitiño Shannon Herndon Blas Couto 《Neurocase》2018,24(1):16-30
Posterior cortical atrophy (PCA) is a rare neurodegenerative syndrome characterized by initial predominant visuoperceptual deficits followed by a progressive decline in other cognitive functions. This syndrome has not been as thoroughly described as other dementias, particularly from a neuropsychological evolution perspective with only a few studies describing the evolution of its cognitive progression. In this investigation we review the literature on this rare condition and we perform a 7-year neuropsychological and neuroradiological follow-up of a 64-year-old man with PCA. The subject’s deficits initially appeared in his visuoperceptual skills with later affectation appearing in language and other cognitive functions, this being coherent with the patient’s parieto-temporal atrophy evolution. 相似文献