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711.
Giuseppe Mameli Luciana Poddighe Vito Astone Giuseppe Delogu Giannina Arru Stefano Sotgiu Caterina Serra Antonina Dolei 《Journal of virological methods》2009,161(1):98-106
Two components of the HERV-W family of human endogenous retroviruses are activated during multiple sclerosis (MS) and proposed immunopathogenic co-factors: MSRV (MS-associated retrovirus), and ERVWE1 (whose env protein, syncytin-1, reaches the plasma membrane). MSRVenv and syncytin-1 are closely related, and difficult to distinguish each other. The sequences of extracellular MSRVenv and of syncytin-1 available in GenBank were compared with those found in MS patients and controls of the cohort under study. With respect to syncytin-1, MSRVenv sequences have a 12-nucleotide insertion in the trans-membrane moiety. Based on this insertion, discriminatory real-time PCR assays were developed, that can amplify selectively either MSRVenv or syncytin-1. The data of MS patients and controls indicated that MSRV and ERVWE1 are both expressed in the brain of MS patients, while only MSRV is present in the blood; MSRV was released in culture by PBMCs of MSRV-producer individuals. These cells expressed the complete MSRVenv gene in the absence of syncytin-1 expression, up to the final, fully glycosylated envelope protein product, since western blot staining with anti-HERV-Wenv antibody detected two bands of the same molecular weight (73 and 61 kDa) of the fully glycosylated and partially glycosylated HERV-Wenv uncleaved proteins. Beyond MSRVenv DNA copy numbers were more abundant in MS patients than in healthy humans, while syncytin-1 were unchanged. These findings reinforce the link between MSRV and MS. 相似文献
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714.
Aβ42 production in brain capillary endothelial cells after oxygen and glucose deprivation 总被引:1,自引:0,他引:1
Bulbarelli A Lonati E Brambilla A Orlando A Cazzaniga E Piazza F Ferrarese C Masserini M Sancini G 《Molecular and cellular neurosciences》2012,49(4):415-422
Although the diverse triggers of AD are still under debate, the hypothesis of the contribution of cerebrovascular deficiencies has emerged in recent years. Cerebrovascular dysfunction may precede cognitive decline and onset of neurodegeneration. Indeed, the toxic Aβ(42) aggregates constituting senile plaques, one of AD hallmarks, is often detected as amorphous material or fine fibrils in the brain capillary of AD patients. Aβ(42) causing cerebral microangiopathy might originate either from the circulating blood, the vessel wall itself or the brain parenchyma. In the present investigation we show, for the first time, that in rat brain capillary endothelial cells (RBE4), in vitro oxygen glucose deprivation treatment elicits 250% of Aβ(42) peptide production increase through a mechanism that involves the hypoxia inducible factor-1-mediated β-secretase (BACE1) up-regulation. Furthermore, we observed a time dependent increase of amyloid protein precursor (AβPP) gene and protein expression, confirming previous reports which established the existence of AβPP in the cerebrovascular domain. Our experimental evidences point out that ischemic events may directly contribute in brain capillary endothelial cells to the enhancement of the amyloidogenic metabolism, leading to intracellular deposition of Aβ(42). This events may contribute to the impairment of Aβ brain clearance and AD related blood brain barrier dysfunctions. 相似文献
715.
Marenco S Stein JL Savostyanova AA Sambataro F Tan HY Goldman AL Verchinski BA Barnett AS Dickinson D Apud JA Callicott JH Meyer-Lindenberg A Weinberger DR 《Neuropsychopharmacology》2012,37(2):499-507
The purpose of this study was to examine measures of anatomical connectivity between the thalamus and lateral prefrontal cortex (LPFC) in schizophrenia and to assess their functional implications. We measured thalamocortical connectivity with diffusion tensor imaging (DTI) and probabilistic tractography in 15 patients with schizophrenia and 22 age- and sex-matched controls. The relationship between thalamocortical connectivity and prefrontal cortical blood-oxygenation-level-dependent (BOLD) functional activity as well as behavioral performance during working memory was examined in a subsample of 9 patients and 18 controls. Compared with controls, schizophrenia patients showed reduced total connectivity of the thalamus to only one of six cortical regions, the LPFC. The size of the thalamic region with at least 25% of model fibers reaching the LPFC was also reduced in patients compared with controls. The total thalamocortical connectivity to the LPFC predicted working memory task performance and also correlated with LPFC BOLD activation. Notably, the correlation with BOLD activation was accentuated in patients as compared with controls in the ventral LPFC. These results suggest that thalamocortical connectivity to the LPFC is altered in schizophrenia with functional consequences on working memory processing in LPFC. 相似文献
716.
Demurtas A Aliberti S Bonello L Di Celle PF Cavaliere C Barreca A Novero D Stacchini A 《American journal of clinical pathology》2011,135(4):541-555
Composite lymphoma (CL) is a rare occurrence of 2 or more morphologically and immunophenotypically distinct lymphoma clones in a single anatomic site. A retrospective analysis of 1,722 solid tissue samples clinically suggestive of lymphoma was carried out in our institute during a 12-year period to evaluate the efficacy of flow cytometry (FC) in identifying CL. We report 17 CL cases. A strong correlation between morphologic findings and FC was observed in 13 cases (76%). In the 4 cases diagnosed as non-Hodgkin lymphoma plus Hodgkin lymphoma, although FC did not detect Reed-Sternberg cells, it accurately identified the neoplastic B- or T-cell component. In 3 cases, FC indicated the need to evaluate an additional neoplastic component that was not morphologically evident. Our data demonstrate that FC immunophenotyping of tissues may enhance the performance of the diagnostic morphologic evaluation of CL. To the best of our knowledge, this is the first report in the literature of a wide series of CL studied also by FC. 相似文献
717.
Saitta C Pontisso P Brunetto MR Fargion S Gaeta GB Niro GA Picciotto A Smedile A Squadrito G Raimondo G 《Antiviral therapy》2006,11(7):931-934
BACKGROUND: Hepatitis C virus (HCV) is believed to exert a suppressive effect on hepatitis B virus (HBV) in most HBV/HCV-coinfected patients; once HCV is cured by interferon-based therapy, these patients may show HBV reactivation. However, recent evidence revealed that the virological status in HBV/HCV-untreated individuals may vary over time and may show fluctuating profiles. METHODS: To evaluate the behaviour of apparently inactive HBV infection in patients under treatment for a concurrent HCV infection, we performed a prospective study that evaluated nine consecutive patients (eight males with a median age of 45.9 years, and one female aged 62 years) longitudinally followed-up with bi-monthly evaluation of HBV/HCV viraemia levels and liver biochemistry during a 1-year treatment with interferon plus ribavirin. RESULTS: In seven cases the HBV infection maintained its inactive status independently of the HCV response to therapy. By contrast, two non-responder cases with persistently high HCV RNA levels showed HBV DNA flairs during the follow-up, indicating a status of active HBV infection with fluctuating virological profiles. CONCLUSIONS: This study suggests that the HBV behaviour may be independent of the HCV activity during anti-HCV therapy in HBV/HCV-coinfected patients, and that the HBV virological profile should be monitored to recognize possible reactivations that might lead to more proper therapeutic choices or adjustments. 相似文献
718.
Antonina N. Mutoro Ada L. Garcia Elizabeth W. Kimani-Murage Charlotte M. Wright 《Maternal & child nutrition》2022,18(1):e13261
We aimed to describe the co-occurrence of known risk factors for undernutrition and the prevalence of modifiable risks in wasted, stunted and healthy children. Quota sampling was used to recruit healthy [weight for age Z scores (WAZ) > ?2 SD] and undernourished [weight for length (WLZ) or WAZ scores ≤ ?2 SD] children aged 6–24 months from seven clinics in low-income areas of Nairobi. Structured interviews were used to identify exposure to socioeconomic, water and hygiene, infant feeding, dietary and behavioural risks (low interest in food, high food refusal and force feeding). We recruited 92 wasted WLZ ≤ ?2 SD, 133 stunted (length for age Z scores LAZ ≤ ?2 SD) and 172 healthy (LAZ and WLZ > 2SD) children. Nearly all children were exposed to hygiene risks (90%) and low dietary diversity (95%) regardless of nutritional status. Stunted children were more likely to be exposed to socio-economic risks (54% healthy, 64% wasted and 72% stunted; P = 0.001). Compared with healthy children, wasted and stunted children were more likely to be exposed to infant feeding (25% healthy, 40% wasted and 41% stunted; P = 0.02) and behaviour risks (24% healthy, 49% wasted, and 44% stunted; P = 0.004). Overall, wasted and stunted children were twice as likely to be exposed to more than three risks (23% healthy, 48% wasted, and 50% stunted; P = <0.001). They were also more likely to be exposed to more than three modifiable risks (dietary, handwashing and behaviour risks). Wasting and stunting are associated with exposure to multiple risk factors, many of which are potentially modifiable using targeted advice. 相似文献
719.
Anastasi G Cutroneo G Trimarchi F Santoro G Bruschetta D Bramanti P Pisani A Favaloro A 《International journal of molecular medicine》2004,14(6):989-999
The sarcoglycan subcomplex (SGC) is a well-known system of interaction between extracellular matrix and sarcolemma-associated cytoskeleton in skeletal and cardiac muscle. The SGC is included in the DGC made up of sarcoplasmic subcomplex and a dystroglycan subcomplex. Recent developments in molecular genetics have demonstrated that the mutation of each single sarcoglycan gene, causes a series of recessive autosomal muscular dystrophies, dystrophin-positive, called sarcoglycanopathies or limb girdle muscular dystrophies. Our recent studies have demonstrated that costameres are a proteic machinery made up of DGC and vinculin-talin-integrin system, also revealing the colocalization of sarcoglycans and integrins in adult human skeletal muscle. These results may support the hypothesis of the existence of a bidirectional signalling between sarcoglycans and integrins in cultured L6 myocytes. The hypothesis of bidirectional signalling between sarcoglycans and integrins could be supported by the identification of a skeletal and cardiac muscle filamin2 as a gamma-sarcoglycan, delta-sarcoglycan and, hypothetically, beta1 integrin interacting protein. Our results, acquired with an immunofluorescence study on adult human skeletal muscle affected by LGMD type 2D and 2C, showed that in LGMD2D: a) alpha-sarcoglycan staining is severely reduced; b) the beta-gamma-delta-sarcoglycan subunit and all tested integrins staining are clearly detectable; c) filamin2 is normal and shows a costameric distribution. In LGMD2C: a) alpha-sarcoglycan staining is preserved; b) the beta-gamma-delta-sarcoglycan subunit staining is severely reduced; c) the alpha7B-integrin is slightly reduced and beta1D-integrin is severely reduced; d) filamin2 is severely reduced. Other tested proteins of the two systems show a normal staining pattern in both sarcoglycanopathies. Our study seems to confirm, for the first time on adult human skeletal muscle of subjects affected by LGMDs, the hypo-theses of: a) the existence, in mouse myotubes in culture, of two distinct subunits in sarcoglycans subcomplex; b) the presence of a bidirectional signalling between sarcoglycans and integrins, previously demonstrated on rat cultured L6 myocytes; c) the interaction of FLN2 with both sarcoglycans and integrins. These results may stimulate the search of yet unidentified common interactors of both fiber-extracellular matrix interaction systems. 相似文献
720.
Rebecca Sharp Andrea Gordon Antonina Mikocka-Walus Jessie Childs Carol Grech Melita Cummings Adrian Esterman 《Journal of the Association for Vascular Access》2013,18(4):234-238
BackgroundPeripherally inserted central catheters (PICCs) are increasingly inserted by trained registered nurses, necessitating the development of specialized skills such as the use of ultrasound. The selection of an adequately sized vein is an important factor in reducing adverse events such as deep vein thrombosis. However, PICC nurses may receive minimal training in the use of ultrasound for vein measurement.ObjectiveWe aimed to demonstrate the reliability of a vein measurement protocol using ultrasound by a PICC nurse trained in sonography.MethodsThe diameter of the basilic, brachial, and cephalic veins in the left arms of healthy participants (n = 12) were measured using ultrasound by a PICC nurse and a sonographer. A PICC nurse performed the measurement twice and the sonographer once; the PICC nurse's results were compared for intra-rater reliability and compared with the sonographer for inter-rater reliability. The results were analyzed using intraclass correlation coefficients (ICCs).ResultsInter-rater reliability between the PICC nurse and the sonographer was adequate, the ICC for the brachial vein was 0.60 (95% confidence interval [CI], 0.06-0.87), basilic vein ICC was 0.87 (95% CI, 0.58-0.96) and cephalic vein ICC was 0.77 (95% CI, 0.39-0.93). Intra-rater reliability of the PICC nurse was higher; the ICC for the brachial vein was 0.80 (95% CI, 0.44-0.94), basilic vein ICC was 0.92 (95% CI, 0.67-0.98), and cephalic vein ICC was 0.78 (95% CI, 0.40-0.93).ConclusionsUsing a suitable protocol, a PICC nurse was able to measure vein diameter reliably when compared with a sonographer and consistently replicate these results. 相似文献