Cover titleIncreased blood viscosity in patients with small artery occlusion Key wordsblood viscosity, ischemic stroke, small artery occlusion, pathogenesis, rheology, dehydration 2 Abstract Background and Purpose: High blood viscosity causes blood stagnation and subsequent

NIR fluorescence imaging is valuable in monitoring the behaviors of donor cells in the rodent brain. The results would allow new opportunities to develop noninvasive NIR fluorescence imaging as a modality to track the BMSCs transplanted into the brain.

The findings suggest that the transplanted BMSCs acquire neural cell phenotypes around the injury site and contribute to rebuild the neural circuits, including the corticospinal tract, promoting functional recovery of the hind limbs.

Background and purposeMoyamoya disease (MMD) is a slow, progressive steno-occlusive disease, arising in the terminal portions of the cerebral internal carotid artery. However, the functions and characteristics of the endothelial cells (ECs) in MMD are unknown. We analyzed these features using induced pluripotent stem cell (iPSC)-derived ECs.MethodsiPSC lines were established from the peripheral blood of three patients with MMD carrying the variant RNF213 R4810K, and three healthy persons used as controls. After the endothelial differentiation of iPSCs, CD31+CD144+ cells were purified as ECs using a cell sorter. We analyzed their proliferation, angiogenesis, and responses to some angiogenic factors, namely VEGF, bFGF, TGF-β, and BMP4. The ECs were also analyzed using DNA microarray and proteomics to perform comprehensive gene and protein expression analysis.ResultsAngiogenesis was significantly impaired in MMD regardless of the presence of any angiogenic factor. On the contrary, endothelial proliferation was not significant between control- and MMD-derived cells. Regarding DNA microarray, pathway analysis illustrated that extracellular matrix (ECM) receptor-related genes, including integrin β3, were significantly downregulated in MMD. Proteomic analysis revealed that cytoskeleton-related proteins were downregulated and splicing regulation-related proteins were upregulated in MMD.ConclusionsDownregulation of ECM receptor-related genes may be associated with impaired angiogenic activity in ECs derived from iPSCs from patients with MMD. Upregulation of splicing regulation-related proteins implied differences in splicing patterns between control and MMD ECs.

The findings suggest that surgical transplantation of tissue-engineered BMSCs onto the intact neocortex enhances the engraftment of donor cells around the cerebral infarct. These data may be useful in developing a noninvasive but efficient paradigm in neural tissue engineering. TGP hydrogel can be a promising candidate for valuable scaffolds in BMSC transplantation for central nervous system disorders because of its unique biochemical properties.

Transplanted bone marrow stromal cells (BMSC) promote functional recovery after spinal cord injury (SCI) through multiple mechanisms. A Rho kinase inhibitor, Fasudil also enhances axonal regeneration. This study was aimed to evaluate whether combination therapy of BMSC transplantation and Fasudil further enhances axonal regeneration and functional recovery in rats subjected to SCI. Fasudil or vehicle was injected for 2 weeks. BMSC or vehicle transplantation into the rostral site of SCI was performed at 7 days after injury. Neurological symptoms were assessed throughout the experiments. Fluoro-Ruby was injected into the dorsal funiculus of the rostral site of SCI at 63 days after injury. The fate of the transplanted BMSC was examined using immunohistochemistry. BMSC transplantation significantly increased the number of Fluoro-Ruby -labeled fibers of the dorsal corticospinal tracts at the caudal site of SCI, enhancing functional recovery of the hind limbs. Some of the engrafted BMSC were positive for Fluoro-Ruby, neuronal specific nuclear protein and microtubule-associated protein-2, suggesting that they acquired neuronal phenotypes and built synaptic connection with the host's neural circuits. Fasudil treatment also improved axonal continuity, but did not promote functional recovery. Combination therapy dramatically increased the number of Fluoro-Ruby-labeled fibers of the dorsal corticospinal tracts at the caudal site of SCI, but did not further boost the therapeutic effects on locomotor function by BMSC transplantation. The findings suggest that BMSC transplantation and Fasudil provide synergistic effects on axon regeneration after SCI, although further studies would be necessary to further enhance functional recovery.

Intra-arterial transplantation may be a valuable option for prompt, noninvasive delivery of BMSCs to the injured CNS tissue, enhancing functional recovery after TBI. In vivo optical imaging may provide important information on the intracerebral behaviors of donor cells by noninvasive, serial visualization.

Endovascular thrombectomy (EVT) is the preferred treatment strategy for patients with acute ischemic stroke (AIS). However, clinical outcome and prognosis in patients who undergo EVT in response to AIS with concomitant malignancy have not been fully elucidated. Data of patients with malignancy who underwent EVT at participating institutions between January 2015 and April 2019 were retrospectively analyzed. Patient characteristics, treatment methods, posttreatment strategy, and long-term prognosis were evaluated in 12 patients with prediagnoses of malignancy. Good revascularization (TICI 2b or higher) was achieved in 10 of 12 patients. Among the eight patients who survived more than 2 weeks from onset, four patients showed good clinical outcome [modified Rankin Scale (mRS) <2] at 60 days posttreatment and were able to continue treatment for malignancy. However, seven of eight patients died within a year of EVT (median survival, 83 days) due to progression of malignancy. One-year survival was achieved in only one patient whose etiology of stroke was determined as infectious endocarditis and not Trousseau syndrome. Even after successful revascularization and good short-term clinical outcome, the long-term prognosis after thrombectomy in patients with malignancy was poor. Thrombectomy for concomitant malignancy requires judicious decision, and further studies are necessary to fully elucidate its efficacy.