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排序方式: 共有380条查询结果,搜索用时 46 毫秒
61.
62.
Sonia Coni Silvia Maria Serrao Zuleyha Nihan Yurtsever Laura Di Magno Rosa Bordone Camilla Bertani Valerio Licursi Zaira Ianniello Paola Infante Marta Moretti Marialaura Petroni Francesca Guerrieri Alessandro Fatica Alberto Macone Enrico De Smaele Lucia Di Marcotullio Giuseppe Giannini Marella Maroder Enzo Agostinelli Gianluca Canettieri 《Cell death & disease》2020,11(12)
63.
Girolamo A. Vitello Francesco Calì Mirella Vinci Carmela Scuderi Francesca LEpiscopo Antonino Musumeci Sebastiano A. Musumeci Antonio G. Nicotera 《Journal of musculoskeletal & neuronal interactions》2020,20(4):610
Spinal muscular atrophy (SMA) refers to a group of genetic neuromuscular disorders affecting lower motor neurons causative of numerous phenotypes. To date, according to the age of onset, maximum muscular activity achieved, and life expectation four types of SMA are recognized, all caused by mutations in the SMN1 gene with SMN2 copy number influencing disease severity. Herein, we describe the case of a 31-year-old young male with normal psychomotor development who has experienced fatigue, cramps, and muscle fasciculations in the lower limbs for a period of 2 months. Based on electrophysiological and clinical findings we performed SMA genetic, clinical exome and RNA expression of candidate genes which led us to suggest SMN1-SMN2 genes [(2+0) and (0+0)] combination as possibly being implicated in the phenotype. 相似文献
64.
Elisa Canu Federica Agosta Sebastiano Galantucci Adriano Chiò Nilo Riva Vincenzo Silani Andrea Falini Giancarlo Comi Massimo Filippi 《PloS one》2013,8(12)
Objectives
This is a cross-sectional study aimed at investigating cognitive performances in patients with primary lateral sclerosis (PLS) and using diffusion tensor (DT) magnetic resonance imaging (MRI) to determine the topographical distribution of microstructural white matter (WM) damage in patients with or without cognitive deficits.Methods
DT MRI scans were obtained from 21 PLS patients and 35 age- and sex-matched healthy controls. All PLS patients underwent a comprehensive neuropsychological battery. Tract-based-spatial-statistics (TBSS) was used to perform a whole-brain voxel-wise analysis of fractional anisotropy (FA), axial, radial (radD) and mean diffusivity (MD).Results
Ten PLS patients had abnormal scores in at least one neuropsychological test (PLS with cognitive deficits, PLS-cd). Compared with healthy controls and cognitively unimpaired PLS patients (PLS-cu), PLS-cd cases showed decreased FA and increased MD and radD in the corticospinal tract (CST), corpus callosum, brainstem, anterior limb of internal capsule, superior and inferior longitudinal fasciculi, fornix, thalamic radiations, and parietal lobes, bilaterally. Compared with healthy controls, PLS-cd patients showed further decreased FA and increased radD in the cerebellar WM, bilaterally. Compared with controls, PLS-cu patients showed decreased FA in the mid-body of corpus callosum. In PLS, executive and language test scores correlated with WM damage.Conclusions
This is the first study evaluating the relationship between cognitive performance and WM tract damage in PLS patients. PLS can be associated with a multi-domain cognitive impairment. WM damage to interhemispheric, limbic and major associative WM tracts seem to be the structural correlate of cognitive abnormalities in these patients. 相似文献65.
Gu G Barone I Gelsomino L Giordano C Bonofiglio D Statti G Menichini F Catalano S Andò S 《Journal of cellular physiology》2012,227(10):3363-3372
Breast cancer is the most frequent tumor and a major cause of death among women. Estrogens play a crucial role in breast tumor growth, which is the rationale for the use of hormonal antiestrogen therapies. Unfortunately, not all therapeutic modalities are efficacious and it is imperative to develop new effective antitumoral drugs. Oldenlandia diffusa (OD) is a well-known medicinal plant used to prevent and treat many disorders, especially cancers. The aim of this study was to investigate the effects of OD extracts on breast cancer cell proliferation. We observed that OD extracts strongly inhibited anchorage-dependent and -independent cell growth and induced apoptosis in estrogen receptor alpha (ERα)-positive breast cancer cells, whereas proliferation and apoptotic responses of MCF-10A normal breast epithelial cells were unaffected. Mechanistically, OD extracts enhance the tumor suppressor p53 expression as a result of an increased binding of ERα/Sp1 complex to the p53 promoter region. Finally, we isolated ursolic and oleanolic acids as the bioactive compounds able to upregulate p53 expression and inhibit breast cancer cell growth. These acids were greatly effective in reducing tamoxifen-resistant growth of a derivative MCF-7 breast cancer cell line resistant to the antiestrogen treatment. Our results evidence how OD, and its bioactive compounds, exert antiproliferative and apoptotic effects selectively in ERα-positive breast cancer cells, highlighting the potential use of these herbal extracts as breast cancer preventive and/or therapeutic agents. 相似文献
66.
The differentiation of glial cells in developing, neonatal, adult and neoplastic human adrenal medulla has been studied immunohistochemically.
From 8 to 28 weeks' gestational age, S-100 protein and its β-subunit revealed two different glial cell populations in adrenal
glands, namely Schwann-like and sustentacular cells. Schwann-like cells were spindle-shaped cells forming a continuous layer
around groups of sympathetic neuroblasts, often in contact with Schwann cells of nerve fibres entering neuroblastic groups.
Sustentacular cells were round or oval cells with dendritic cytoplasmic processes; they were not associated with nerve fibres
and mingled both with sympathetic neuroblasts and differentiating chromaffin cells. The developmental fate of Schwann-like
cells was different from that of sustentacular cells. Schwann-like cells disappeared from the 28th week of gestational age,
in association with the disappearance of sympathetic neuroblastic groups, and they were rarely found in neonatal and adult
adrenal medulla. In contrast, sustentacular cells persisted between medullary chromaffin cells, and their number and dendritic
cytoplasmic processes progressively increased from foetus to adult. In eight cases of primitive adrenal neuroblastic tumours
of neonatal age (five undifferentiated neuroblastomas and three ganglioneuroblastomas), Schwann-like cells were found at the
periphery of tumoral nests with a lobular growth pattern, while rare sustentacular cells were associated with neuroblasts.
In two cases of adult phaeochromocytomas, only sustentacular cells were detected between chromaffin tumoral cells. Our findings
suggest that the glial cell types and their distribution in primitive adrenal medulla tumours closely resemble those observed
during development in the groups of adrenal sympathetic neuroblasts and in the clusters of chromaffin cells 相似文献
67.
Redside dace Clinostomus elongatus (Teleostei: Cyprinidae) is a species of conservation concern that is declining throughout its range as a result of habitat fragmentation, degradation and loss. We characterized the genetic structure and diversity of redside dace populations across the species range using mitochondrial and microsatellite data to inform conservation efforts and assess how historical and recent events have shaped genetic structure and diversity within and among populations. Phylogeographic structure among 28 redside dace populations throughout southern Ontario (Canada) and the United States was assessed by sequence analysis of the mitochondrial cytochrome b and ATPase 6 and 8 genes. Populations were also genotyped using ten microsatellite loci to examine genetic diversity within and among populations as well as contemporary spatial structuring. Mitochondrial DNA sequence data revealed three geographically distinct lineages, which were highly concordant with groupings identified by microsatellite analysis. The combined genetic data refute published glacial refugia hypotheses of a single Mississippian refugium or of two lineages associated with Mississippian and Atlantic refugia. Secondary contact between the two eastern groups was documented in the Allegheny River drainage and tributaries to Lake Ontario. With the exception of several allopatric populations within the Allegheny watershed, high genetic structuring among populations suggests their isolation, indicating that recovery efforts should be population-based. 相似文献
68.
Leyla Najafi Sebastiano Bellani Reinier Oropesa‐Nuñez Alberto Ansaldo Mirko Prato Antonio Esau Del Rio Castillo Francesco Bonaccorso 《Liver Transplantation》2018,8(16)
2D transition metal‐dichalcogenides are emerging as efficient and cost‐effective electrocatalysts for the hydrogen evolution reaction (HER). However, only the edge sites of their trigonal prismatic phase show HER‐electrocatalytic properties, while the basal plane, which is absent of defective/unsaturated sites, is inactive. Herein, the authors tackle the key challenge of increasing the number of electrocatalytic sites by designing and engineering heterostructures composed of single‐/few‐layer MoSe2 flakes and carbon nanomaterials (graphene or single‐wall carbon nanotubes) produced by solution processing. The electrochemical coupling between the materials that comprise the heterostructure effectively enhances the HER‐electrocatalytic activity of the native MoSe2 flakes. The optimization of the mass loading of MoSe2 flakes and their electrode assembly via monolithic heterostructure stacking provides a cathodic current density of 10 mA cm?2 at overpotential of 100 mV, a Tafel slope of 63 mV dec?1, and an exchange current density (j0) of 0.203 µA cm?2. In addition, thermal and chemical treatments are exploited to texturize the basal planes of the MoSe2 flakes (through Se‐vacancies creation) and to achieve in situ semiconducting‐to‐metallic phase conversion, respectively, thus they activate new HER‐electrocatalytic sites. The as‐engineered electrodes show a 4.8‐fold enhancement of j0 and a decrease in the Tafel slope to 54 mV dec?1. 相似文献
69.
Secretome Analysis of Hypoxia‐Induced 3T3‐L1 Adipocytes Uncovers Novel Proteins Potentially Involved in Obesity 下载免费PDF全文
Anna Elisa Laria Sebastiano Messineo Biagio Arcidiacono Mariaconcetta Varano Eusebio Chiefari Robert K. Semple Nuno Rocha Diego Russo Giovanni Cuda Marco Gaspari Antonio Brunetti Daniela P. Foti 《Proteomics》2018,18(7)
In the obese state, as adipose tissue expands, adipocytes become hypoxic and dysfunctional, leading to changes in the pattern of adipocyte‐secreted proteins. To better understand the role of hypoxia in the mechanisms linked to obesity, we comparatively analyzed the secretome of murine differentiated 3T3‐L1 adipocytes exposed to normoxia or hypoxia for 24 h. Proteins secreted into the culture media were precipitated by trichloroacetic acid and then digested with trypsin. The peptides were labeled with dimethyl labeling and analyzed by reversed phase nanoscale liquid chromatography coupled to a quadrupole Orbitrap mass spectrometer. From a total of 1508 identified proteins, 109 were differentially regulated, of which 108 were genuinely secreted. Factors significantly downregulated in hypoxic conditions included adiponectin, a known adipokine implicated in metabolic processes, as well as thrombospondin‐1 and ‐2, and matrix metalloproteinase‐11, all multifunctional proteins involved in extracellular matrix (ECM) homeostasis. Findings were validated by Western blot analysis. Expression studies of the relative genes were performed in parallel experiments in vitro, in differentiated 3T3‐L1 adipocytes, and in vivo, in fat tissues from obese versus lean mice. Our observations are compatible with the concept that hypoxia may be an early trigger for both adipose cell dysfunction and ECM remodeling. 相似文献
70.
Mauro Serafini Antonella di Fabio Sebastiano Foddai Mauro Ballero Ferruccio Poli 《Biochemical Systematics and Ecology》1995,23(7-8):855-858
The occurrence of phenylpropanoid glycosides in a number of Orobanche spp. collected in Italy is shown and chemosystematic implications are discussed. 相似文献