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991.
ABSTRACT

Background: Coil embolization with multiple overlapping stents was performed as an alternative treatment option for blood blister–like aneurysms (BBAs). However, coil placement into the BBAs has the inherent risks of rupture and regrowth. We describe a safe dense coil packing technique into and just proximal of BBAs using a semi-jailing technique for the treatment of BBAs of the internal carotid artery (ICA) and report the long-term clinical outcomes.

Methods: The technique involves the partial deployment of a self-expanding and retrievable stent from the ICA bifurcation to the mid-portion of a BBA followed by coil embolization with gradual unsheathing of the stent from the BBA to its just proximal portion. Seventeen patients were treated using this technique (10 women; mean age, 47.9 ± 11 years; overall mean clinical follow-up period, 42.3 ± 22.8 months). Technique safety and feasibility, and follow-up angiographic results and clinical outcomes (modified Rankin Scale, mRS) were evaluated.

Results: Procedures were successfully applied without any procedure-related complications. Immediate post-treatment angiograms showed total obliteration of the BBAs in all 17 patients. Follow-up angiograms, which were available in 15 (88.2%) patients, showed complete resolution of BBAs. Fourteen (82.4%) of 17 patients achieved favorable clinical outcomes (mRS ≤ 2).

Conclusions: Forward deployed coil embolization with multiple overlapping stents offers a safe and effective reconstructive endovascular technique for the treatment of the BBAs.  相似文献   
992.
In this study, positron emission tomography (PET) imaging with a radioligand to adenosine A2A receptors (A2AR)—a potent regulator of inflammation—was used to gain insight into the molecular alterations in normal-appearing white matter (NAWM) and gray matter (GM) in secondary progressive multiple sclerosis (SPMS). Normal-appearing white matter and GM, despite seeming normal in conventional mangnetic resonance imaging (MRI), are important loci of widespread inflammation, neuronal damage, and source of progressive disability in multiple sclerosis (MS). Dynamic PET imaging using A2AR-specific [11C]TMSX and brain MRI with diffusion tensor imaging were performed to eight SPMS patients and seven healthy controls. Distribution volumes (VT) of [11C]TMSX were analyzed from 13 regions of interest using Logan plot with arterial plasma input. The SPMS patients had significantly increased [11C]TMSX-VT in NAWM compared with controls (mean (s.d.): 0.55 (±0.08) vs. 0.45 (±0.05); P=0.036). Both the increased VT and the decreased fractional anisotropy (FA) in NAWM were associated with higher expanded disability status scale (EDSS) scores (P=0.030 and P=0.012, respectively), whereas the T2-lesion load of SPMS patients did not correlate with EDSS. This study shows, that A2ARs are increased in the brain of SPMS patients, and that [11C]TMSX-PET provides a novel approach to learn about central nervous system pathology in SPMS in vivo.  相似文献   
993.
The brain is in many ways an immunologically and pharmacologically privileged site. The blood–brain barrier (BBB) of the cerebrovascular endothelium and its participation in the complex structure of the neurovascular unit (NVU) restrict access of immune cells and immune mediators to the central nervous system (CNS). In pathologic conditions, very well-organized immunologic responses can develop within the CNS, raising important questions about the real nature and the intrinsic and extrinsic regulation of this immune privilege. We assess the interactions of immune cells and immune mediators with the BBB and NVU in neurologic disease, cerebrovascular disease, and intracerebral tumors. The goals of this review are to outline key scientific advances and the status of the science central to both the neuroinflammation and CNS barriers fields, and highlight the opportunities and priorities in advancing brain barriers research in the context of the larger immunology and neuroscience disciplines. This review article was developed from reports presented at the 2011 Annual Blood-Brain Barrier Consortium Meeting.  相似文献   
994.
Mobilization of remyelinating cells spontaneously occurs in the adult brain. These cellular resources are specially active after demyelinating episodes in early phases of multiple sclerosis (MS). Indeed, oligodendrocyte precursor cells (OPCs) actively proliferate, migrate to and repopulate the lesioned areas. Ultimately, efficient remyelination is accomplished when new oligodendrocytes reinvest nude neuronal axons, restoring the normal properties of impulse conduction. As the disease progresses this fundamental process fails. Multiple causes seem to contribute to such transient decline, including the failure of OPCs to differentiate and enwrap the vulnerable neuronal axons. Regenerative medicine for MS has been mainly centered on the recruitment of endogenous self-repair mechanisms, or on transplantation approaches. The latter commonly involves grafting of neural precursor cells (NPCs) or neural stem cells (NSCs), with myelinogenic potential, in the injured areas. Both strategies require further understanding of the biology of oligodendrocyte differentiation and remyelination. Indeed, the success of transplantation largely depends on the pre-commitment of transplanted NPCs or NSCs into oligodendroglial cell type, while the endogenous differentiation of OPCs needs to be boosted in chronic stages of the disease. Thus, much effort has been focused on finding molecular targets that drive oligodendrocytes commitment and development. The present review explores several aspects of remyelination that must be considered in the design of a cell-based therapy for MS, and explores more deeply the challenge of fostering oligodendrogenesis. In this regard, we discuss herein a tool developed in our research group useful to search novel oligodendrogenic factors and to study oligodendrocyte differentiation in a time- and cost-saving manner.  相似文献   
995.
996.
997.
We have previously demonstrated that Sox17 expression is prominent at developmental stages corresponding to oligodendrocyte progenitor cell (OPC) cycle exit and onset of differentiation, and that Sox17 promotes initiation of OPC differentiation. In this study, we examined Sox17 expression and regulation under pathological conditions, particularly in two animal models of demyelination/remyelination and in post‐mortem multiple sclerosis (MS) brain lesions. We found that the number of Sox17 expressing cells was significantly increased in lysolecithin (LPC)‐induced lesions of the mouse spinal cord between 7 and 30 days post‐injection, as compared with controls. Sox17 immunoreactivity was predominantly detected in Olig2+ and CC1+ oligodendrocytes and rarely in NG2+ OPCs. The highest density of Sox17+ oligodendrocytes was observed at 2 weeks after LPC injection, coinciding with OPC differentiation. Consistent with these findings, in cuprizone‐treated mice, Sox17 expression was highest in newly generated and in maturing CC1+ oligodendrocytes, but low in NG2+ OPCs during the demyelination and remyelination phases. In MS tissue, Sox17 was primarily detected in actively demyelinating lesions and periplaque white matter. Sox17 immunoreactivity was co‐localized with NOGO‐A+ post‐mitotic oligodendrocytes both in active MS lesions and periplaque white matter. Taken together, our data: (i) demonstrate that Sox17 expression is highest in newly generated oligodendrocytes under pathological conditions and could be used as a marker of oligodendrocyte regeneration, and (ii) are suggestive of Sox17 playing a critical role in oligodendrocyte differentiation and lesion repair. GLIA 2013;61:1659–1672  相似文献   
998.
Among the constituent cell types of the multiple sclerosis (MS) plaque, the astrocyte has been the least considered as a player in the pathogenesis of the lesion. Traditionally, it has been assigned a secondary scarring role with little or no role in lesion formation or repair. However, the recent upsurge of interest in the demyelinating condition neuromyelitis optica (NMO) has resulted in NMO being identified as the first disease of myelin in which primary damage to astrocytes, resulting from a humoral immune response that forms against the water channel aquaporin‐4, has been documented. This finding in NMO prompted us to re‐examine data and material from cases of MS displaying active lesions. Our reappraisal revealed unambiguous early damage to perivascular astrocyte end‐feet and to hypertrophic astrocytes in the adjacent parenchyma, but whether this was a primary event was difficult to evaluate due to concomitant edema and inflammation in these acute lesions. The astrocyte damage was long‐lasting since resolving lesions displaying remyelination also showed defects in the integrity of the astrocytic covering around blood vessels. Analysis of our findings and of the astrocytic literature supports multiple roles for the astrocyte in the evolution of changes encountered in MS depending upon lesion stage and lesion topography. At variance with the somewhat inhibitory role of the astrocyte is the abundant and growing evidence for this cell to actively participate in both lesion development and repair. We propose that the unequivocal selective early involvement of the astrocyte in MS lesions may have therapeutic relevance. © 2013 Wiley Periodicals, Inc.  相似文献   
999.
Abstract

In this study of routine service data and census data, the authors explore the influence of socioeconomic status on patients entering an integrated psychotherapy service. Between January 1, 2000, and September 30, 725 patients were assessed and had their Townsend Index of Material Deprivation (TIMD) scores derived from postcodes. Results showed no correlation between TIMD score and those attending their assessment and no significant difference in TIMD score between those allocated to psychoanalytic psychotherapy (PAP) or cognitive–behavioral psychotherapy (CBP) and between those accepted and not accepted for each treatment. No correlation was found between Townsend score and numbers presenting to the service, suggesting that the inverse care law applies. Deprivation is not a predictor of patient allocation to or acceptance for PAP or CBP.  相似文献   
1000.
The introduction of chimeric antigen receptor T-cell (CAR T) therapy has resulted in a paradigm shift in the management of relapsed/refractory B-cell malignancies. Patients with acute lymphoblastic leukemia and non-Hodgkin’s lymphoma who had exhausted all meaningful treatment options now have an opportunity for long-term remission and possibly cure. CAR T is rapidly expanding into the treatment paradigm for multiple myeloma with approvals expected in the near future. CAR T for chronic lymphocytic leukemia may not be far behind, while CAR T studies in Hodgkin lymphoma and acute myeloid leukemia are ongoing. Such therapeutic success brings challenges in toxicity management related to cytokine release syndrome and immune effector cell–associated neurotoxicity syndrome. Our understanding of these unique syndromes is evolving, with predictive models and additional treatment strategies on the horizon. This review aims to summarize the progress of CAR T therapeutics within malignant hematology thus far and highlight ongoing advances in the field.  相似文献   
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