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van Dongen EV, Takashima A, Barth M, Norris DG, Fernández G. Resting-state connectivity between the hippocampus and frontal areas following encoding of face-location associations predicts subsequent recall performance. Neuroimage 2009. [DOI: 10.1016/s1053-8119(09)70175-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
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52
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Kanato K, Nakamura K, Saito I, Takashima A, Tomii Y, Kaba H, Shibata T, Fukuda H, Sato A, Shimada Y. Treatment-related deaths (TRD) in investigator-initiated cancer cooperative group trials: From the datasets of 44 studies (4,964 patients) by the Japan Clinical Oncology Group (JCOG). J Clin Oncol 2009. [DOI: 10.1200/jco.2009.27.15_suppl.6632] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
6632 Background: The proportion of Serious Adverse Events (SAE) including TRDs has a critical impact on choosing a new standard therapy as well as the efficacy of treatment in clinical trials. The proportion of TRD (%TRD) has been reported in a single clinical trial, but an overall % TRD in plural clinical trials has merely been evaluated so far. Methods: The JCOG trials which met both of the following criteria were included in this analysis: i) started after 1995 by 2008, ii) primary analysis was completed. In JCOG, attribution of all reported SAE are classified by Data and Safety Monitoring Committee into 5 categories (definite, probable, possible, unlikely, not related) according to causality to protocol treatment, and the death with causality judged as definite, probable, or possible is defined as TRD. The total number of any deaths and TRD were counted in all included trials and the incidences (%) of TRD were calculated. The association between %TRD and the following trial profiles was evaluated: arm (standard vs. testing), phase, modality and median survival time of each arm. Results: In total, 44 JCOG trials (67 arms) with 4,964 patients were included in the analysis. The number of all deaths and TRD were 2,974 and 60. Thus, the overall %TRD for all enrolled patients was 1.2% (95%CI, 0.9–1.6%), and %TRD among all deaths was 2.0% (95%CI, 1.5–2.6%). Major results of the association between %TRD and trial profiles are shown in the table. The later phase trials showed the lower %TRD, and the trials with shorter MST tended to have higher %TRD. Conclusions: When the trial is in earlier phase and includes more advanced disease, the trial should be planned and performed more carefully about minimization of patient risk. [Table: see text] No significant financial relationships to disclose.
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Sahara N, Maeda S, Takashima A. Tau oligomerization: a role for tau aggregation intermediates linked to neurodegeneration. Curr Alzheimer Res 2009; 5:591-8. [PMID: 19075586 DOI: 10.2174/156720508786898442] [Citation(s) in RCA: 71] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Intracellular accumulation of filamentous tau proteins is a defining feature of neurodegenerative diseases, including Alzheimer's disease, progressive supranuclear palsy, corticobasal degeneration, Pick's disease, and frontotemporal dementia with Parkinsonism linked to chromosome 17, all known collectively as tauopathies. Tau protein is a member of microtubule (MT)-associated proteins. Tau is a highly soluble and natively unfolded protein dominated by a random coil structure in solution. It is believed that aberrant modifications of tau, including phosphorylation, truncation, and conformational changes, induce filamentous aggregation. However, the mechanism underlying the conversion of tau protein from a soluble state to one of insoluble aggregates still remains elusive. The importance of tau aggregation intermediates (e.g. tau dimer, tau multimer, and granular tau oligomer) in disease pathogenesis was suggested by recent studies. Here, we review the latest developments in tracking the structural changes of tau protein and discuss the utility improving our understanding of tau aggregation pathway leading to human tauopathies.
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Ohba T, Shibahara T, Kobayashi H, Takashima A, Nagoshi M, Osanai R, Kubo M. Multifocal granulomatous hepatitis caused by Actinobacillus pleuropneumoniae serotype 2 in slaughter pigs. J Comp Pathol 2008; 139:61-6. [PMID: 18617183 DOI: 10.1016/j.jcpa.2008.04.003] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2007] [Accepted: 04/16/2008] [Indexed: 10/21/2022]
Abstract
In a survey of 66 894 slaughter pigs, 11 animals from three farms were found to have multifocal granulomatous lesions in the liver, caused by Actinobacillus pleuropneumoniae serotype 2. The lesions consisted of epithelioid cells and multinucleated giant cells, with asteroid bodies and discernible gram-negative bacteria. Lymph nodes and spleen were occasionally affected. The results suggested that haematogenous spread had occurred from pre-existing pulmonary infections.
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Takeuchi Y, Uetsuka K, Murayama M, Kikuta F, Takashima A, Doi K, Nakayama H. Complementary Distributions of Amyloid-β and Neprilysin in the Brains of Dogs and Cats. Vet Pathol 2008; 45:455-66. [DOI: 10.1354/vp.45-4-455] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Neprilysin is an amyloid-β-degrading enzyme localized in the brain parenchyma. The involvement of neprilysin in the pathogenesis of Alzheimer's disease has recently received much attention. We examined the localization of neprilysin and amyloid-β, as well as the activity of neprilysin, in the brains of dogs and cats of various ages to clarify the relationship between neprilysin activity and amyloid-β deposition. The distribution of neprilysin was almost identical in dogs and cats, being high in the striatum, globus pallidus, and substantia nigra, but very low in the cerebral cortex. The white matter and hippocampus were negative. Neprilysin activity in the brain regions in dogs and cats was ranked from high to low as follows: thalamus/striatum > cerebral cortex > hippocampus > white matter. Amyloid-β deposition was first detected at 7 and 10 years of age in dogs and cats, respectively, and both the quantity and frequency of deposition increased with age. In both species, amyloid-β deposition appeared in the cerebral cortex and the hippocampus. In summary, the localization of neprilysin and neprilysin activity, and that of amyloid-β, were complementary in the brains of dogs and cats.
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Takashima A, Shirao K, Hirashima Y, Takahari D, Okita N, Akatsuka S, Nakajima TE, Matsubara J, Yasui H, Asakawa T, Kato K, Hamguchi T, Muro K, Yamada Y, Shimada Y. Chemosensitivity of patients with recurrent esophageal cancer receiving perioperative chemotherapy. Dis Esophagus 2008; 21:607-11. [PMID: 18430178 DOI: 10.1111/j.1442-2050.2008.00821.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Perioperative chemotherapy (CT) and chemoradiotherapy are widely used for advanced esophageal cancer. We evaluated the chemosensitivity of patients displaying recurrent esophageal cancer after esophagectomy with perioperative CT. From the database at National Cancer Center Hospital in Tokyo, we extracted recurrent esophageal cancer cases after perioperative CT and evaluated the effectiveness of the first CT against the recurrent disease according to the duration between termination of the original perioperative CT and recurrence with treatment-free intervals (TFIs) <or=6 and >6 months. Systemic CT for their recurrent disease was performed for 30 esophageal cancer patients after perioperative CT. All patients received 5-fluorouracil and cisplatin as perioperative CT, with relapses occurring at TFIs <or=6 months in 11 patients (eight received platinum-containing regimens and three received docetaxel for their recurrent disease) and >6 months in 19 patients (all received platinum-containing regimens). The response rate of patients experiencing a recurrence at TFIs <or=6 and >6 months was 0 and 37% (P = 0.029), the median progression-free survival was 2.8 and 4.8 months (log-rank P = 0.001) and the median overall survival was 6.1 and 10.2 months (log-rank P = 0.012), respectively. Recurrence at the TFI <or=6 months could represent resistance to CT, so regimens may need to be altered depending on a patient's specific TFI.
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57
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Talamini LM, Nieuwenhuis IL, Takashima A, Jensen O. Sleep directly following learning benefits consolidation of spatial associative memory. Learn Mem 2008; 15:233-7. [PMID: 18391183 DOI: 10.1101/lm.771608] [Citation(s) in RCA: 80] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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58
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Abstract
Fibroblasts are fairly easily isolated from a variety of tissues, in this case skin. The cells are fast growing and can be rapidly expanded from small samples. They are suitable for behavioral, functional, biochemical, and genomic studies. Skin fibroblast cultures are started from explants in which the epidermis is enzymatically removed to prevent contamination of the fibroblasts with epidermal cells. Alternatively, the dermis can be enzymatically dissociated to provide a suspension of fibroblasts.
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Sahara N, Maeda S, Yoshiike Y, Mizoroki T, Yamashita S, Murayama M, Park JM, Saito Y, Murayama S, Takashima A. Molecular chaperone-mediated tau protein metabolism counteracts the formation of granular tau oligomers in human brain. J Neurosci Res 2008; 85:3098-108. [PMID: 17628496 DOI: 10.1002/jnr.21417] [Citation(s) in RCA: 68] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Intracellular accumulation of filamentous tau proteins is a defining feature of neurodegenerative diseases termed tauopathies. The pathogenesis of tauopathies remains largely unknown. Molecular chaperones such as heat shock proteins (HSPs), however, have been implicated in tauopathies as well as in other neurodegenerative diseases characterized by the accumulation of insoluble protein aggregates. To search for in vivo evidence of chaperone-related tau protein metabolism, we analyzed human brains with varying degrees of neurofibrillary tangle (NFT) pathology, as defined by Braak NFT staging. Quantitative analysis of soluble protein levels revealed significant positive correlations between tau and Hsp90, Hsp40, Hsp27, alpha-crystallin, and CHIP. An inverse correlation was observed between the levels of HSPs in each specimen and the levels of granular tau oligomers, the latter of which were isolated from brain as intermediates of tau filaments. We speculate that HSPs function as regulators of soluble tau protein levels, and, once the capacity of this chaperone system is saturated, granular tau oligomers form virtually unabated. This is expressed pathologically as an early sign of NFT formation. The molecular basis of chaperone-mediated protection against neurodegeneration might lead to the development of therapeutics for tauopathies. (c) 2007 Wiley-Liss, Inc.
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Ohba T, Shibahara T, Kobayashi H, Takashima A, Minami Y, Kubo M. Granulomatous Lymphadenitis and Pneumonia Associated with Actinobacillus porcitonsillarum in a Slaughter Pig. J Comp Pathol 2007; 137:82-86. [PMID: 17629969 DOI: 10.1016/j.jcpa.2007.04.001] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2006] [Accepted: 03/30/2007] [Indexed: 10/23/2022]
Abstract
Multiple coalescing granulomatous foci were detected in the pulmonary hilar and mediastinal lymph nodes and lung of a slaughtered pig aged 6 months. Haemolytic, Gram-negative bacilli were isolated from the lymph nodes. The isolate (strain TO17214) strongly cross-reacted with sera against Actinobacillus pleuropneumoniae serotype 12 in slide agglutination tests. Comparative 16S rDNA gene sequencing analysis identified strain TO17214 as Actinobacillus porcitonsillarum. Histologically, extensive inflammation took the form of large granulomas consisting of epithelioid cells and multinucleated giant cells in the lymph nodes and lung, and Gram-negative bacilli were discernible in the centres of the lesions. Immunohistochemically, the organisms cross-reacted with polyclonal antibodies against A. pleuropneumoniae serotypes 12 and 2. The results indicated that A. porcitonsillarum, previously considered non-pathogenic, can induce multifocal granulomatous lymphadenitis accompanied by pneumonia in the growing-finishing pig.
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Takahari D, Yamada Y, Okita N, Hirashima Y, Matsubara J, Takashima A, Kato K, Hamaguchi T, Shirao K, Shimada Y, Shimoda T. Relationship of insulin-like growth factor-1 receptor and epidermal growth factor receptor expression to clinical outcomes in patients with colorectal cancer. J Clin Oncol 2007. [DOI: 10.1200/jco.2007.25.18_suppl.4117] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
4117 Background: Insulin-like growth factor-1 receptor (IGF-1R), epidermal growth factor receptor (EGFR), and HER2 have been reported to regulate tumor growth by interfering with apoptosis, cell proliferation, angiogenesis, and metastasis. However, the clinical significance of these molecules in colorectal cancer (CRC) remains undetermined. To gain further insight, we evaluated the prognostic implications of these biomarkers in patients with CRC treated with fluoropyrimidines or irinotecan. Methods: The study group comprised 91 patients who underwent surgery at National Cancer Center Hospital and subsequently received fluoropyrimidines as 1st-line chemotherapy for recurrent or residual tumors. The expressions of IGF-1R, EGFR, and HER2 in surgically removed specimens of primary lesions were analyzed immunohistochemically to determine the prognostic significance of these biomarkers. Results: IGF-1R expression (defined as >10% membranous staining) was found in 81 tumors (89%), EGFR in 77 (85%), and HER2 in 3 (3%). IGF-1R expression significantly correlated with EGFR expression (P=0.038). Overexpression (defined as >50% membranous staining) of IGF-1R was found in 48 tumors (53%), EGFR in 57 (63%), and HER2 in 2 (2%). Overexpression of IGF-1R significantly correlated with shorter survival from the start of 1st-line chemotherapy (P=0.032). Overexpression of EGFR was a significant predictive factor for a clinical response to fluoropyrimidines (P=0.037) and tended to correlate with TTP in patients given irinotecan as 2nd-line therapy (P=0.087). A multivariate analysis of potential prognostic factors showed that IGF-1R expression and worse performance status were independent predictors of poor outcomes ( Table ). Conclusions: IGF-1R and EGFR were highly positive in patients with CRC. Overexpression of IGF-1R predicts a poor outcome, and overexpression of EGFR predicts a good clinical response to fluoropyrimidines. [Table: see text] No significant financial relationships to disclose.
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Takashima A, Petersson KM, Rutters F, Tendolkar I, Jensen O, Zwarts MJ, McNaughton BL, Fernández G. Declarative memory consolidation in humans: a prospective functional magnetic resonance imaging study. Proc Natl Acad Sci U S A 2006; 103:756-61. [PMID: 16407110 PMCID: PMC1334654 DOI: 10.1073/pnas.0507774103] [Citation(s) in RCA: 363] [Impact Index Per Article: 20.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2005] [Indexed: 11/18/2022] Open
Abstract
Retrieval of recently acquired declarative memories depends on the hippocampus, but with time, retrieval is increasingly sustainable by neocortical representations alone. This process has been conceptualized as system-level consolidation. Using functional magnetic resonance imaging, we assessed over the course of three months how consolidation affects the neural correlates of memory retrieval. The duration of slow-wave sleep during a nap/rest period after the initial study session and before the first scan session on day 1 correlated positively with recognition memory performance for items studied before the nap and negatively with hippocampal activity associated with correct confident recognition. Over the course of the entire study, hippocampal activity for correct confident recognition continued to decrease, whereas activity in a ventral medial prefrontal region increased. These findings, together with data obtained in rodents, may prompt a revision of classical consolidation theory, incorporating a transfer of putative linking nodes from hippocampal to prelimbic prefrontal areas.
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63
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Takashima A, Jensen O, Oostenveld R, Maris E, van de Coevering M, Fernández G. Successful declarative memory formation is associated with ongoing activity during encoding in a distributed neocortical network related to working memory: a magnetoencephalography study. Neuroscience 2005; 139:291-7. [PMID: 16325347 DOI: 10.1016/j.neuroscience.2005.05.067] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2005] [Revised: 04/29/2005] [Accepted: 05/06/2005] [Indexed: 10/25/2022]
Abstract
The aim of the present study was to investigate the spatio-temporal characteristics of the neural correlates of declarative memory formation as assessed by the subsequent memory effect, i.e. the difference in encoding activity between subsequently remembered and subsequently forgotten items. Different operations could account for these effects. In particular, it has been proposed that successful memory formation depends on the organization of the information at the time of encoding, an operation accomplished by the working memory system. Consequently, functional magnetic resonance imaging studies have already shown that the very same regions that are involved in certain working memory processes are also involved in declarative memory formation. Here, we used magnetoencephalography to investigate whether the subsequent memory effects in these regions are present throughout picture stimulus presentation, postulating ongoing working memory operations as an effective factor. The results showed that subsequent memory effects began to appear after about 300 ms post stimulus onset over bilateral temporal areas and left parietal regions and were sustained throughout the recording epoch (1000 ms). Roughly parallel to these effects, we identified a left frontal subsequent memory effect, which, however, was less sustained than the other effects. In addition, we revealed a late subsequent memory effect over the right occipital region, which has not been described previously in the event-related potential literature. These sustained subsequent memory effects are suggestive of working memory processes that may enable deep semantic and perceptual processing. Additionally, contextually constrained visual perception after top-down modulation may account for a more efficient encoding of the complex scene.
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64
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Cui D, Yoshiike Y, Park J, Jin Y, Murayama M, Planel E, Tatebayashi Y, Takashima A. P3-245 Participation of GSK-3beta in neurodegeneration. Neurobiol Aging 2004. [DOI: 10.1016/s0197-4580(04)81395-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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65
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Sun X, Sato S, Murayama O, Murayama M, Park JM, Yamaguchi H, Takashima A. Lithium inhibits amyloid secretion in COS7 cells transfected with amyloid precursor protein C100. Neurosci Lett 2002; 321:61-4. [PMID: 11872257 DOI: 10.1016/s0304-3940(01)02583-6] [Citation(s) in RCA: 127] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
To examine the regulation of amyloid secretion in more detail, Abeta sandwich ELISAs with high sensitivity and specificity were developed. Using this technique, we measured Abeta secreted from COS7 cells transiently transfected with APP C100 in the presence of LiCl, a potent glycogen synthase kinase (GSK)-3beta inhibitor. We found that both Abetax-40 and Abetax-42 secretion were reduced by LiCl treatment in a dose-dependent manner. Diminished amyloid secretion was associated with GSK-3beta activity. These results suggest that GSK-3beta might function as a possible mediator for regulating both amyloid deposition and tau pathology in Alzheimer's disease (AD), and that lithium should be re-evaluated as a candidate reagent for preventing AD pathology.
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66
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Kimura N, Nakamura SI, Honda T, Takashima A, Nakayama H, Ono F, Sakakibara I, Doi K, Kawamura S, Yoshikawa Y. Age-related changes in the localization of presenilin-1 in cynomolgus monkey brain. Brain Res 2001; 922:30-41. [PMID: 11730699 DOI: 10.1016/s0006-8993(01)03146-8] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Age-related changes in PS-1 localization were examined in the brains of 22 cynomolgus monkeys ranging in age from embryonic day 87 to 35 years. In embryonic monkey brains, anti-PS-1 antibody N12, which recognizes the PS-1 N-terminal fragment (Ntf) and holo protein, stained immature neuronal cells. In juvenile monkeys, N12 stained large pyramidal neurons, cerebral neocortical neurons, and cerebellar Purkinje's cells. Cytoplasmic staining of these cells was granular in appearance. In aged monkeys, N12 stained neurons in all layers of the neocortex. In contrast, regardless of the age of the animals examined, M5, an anti-PS-1 antibody that specifically recognizes only the PS-1 C-terminal fragment (Ctf), stained neurons in all layers of the neocortex and neurons in the cerebellum. M5 also stained neuropil and white matter, and in aged monkeys, M5 stained swollen neurites of mature senile plaques. Age-related changes in PS-1 expression were further examined using Western blot analysis of mitochondrial, myelin, microsomal, nuclear, synaptosomal, and cytosol fractions isolated from 10 monkey brains ranging in age from embryonic day 87 to 32 years. In all brains, Ntf and Ctf were expressed most abundantly in the microsome fraction. The amount of PS-1 in the nuclear fraction dramatically increased with age. We conclude that the transport of PS-1 diminished with age and that PS-1 fragments accumulated in endoplasmic reticulum (ER) associated with the nuclear membrane.
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67
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Tanemura K, Akagi T, Murayama M, Kikuchi N, Murayama O, Hashikawa T, Yoshiike Y, Park JM, Matsuda K, Nakao S, Sun X, Sato S, Yamaguchi H, Takashima A. Formation of filamentous tau aggregations in transgenic mice expressing V337M human tau. Neurobiol Dis 2001; 8:1036-45. [PMID: 11741399 DOI: 10.1006/nbdi.2001.0439] [Citation(s) in RCA: 106] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Formation of neurofibrillary tangles (NFTs) is the most common feature in several neurodegenerative diseases, including Alzheimer's disease (AD). Here we report the formation of filamentous tau aggregations having a beta-sheet structure in transgenic mice expressing mutant human tau. These mice contain a tau gene with a mutation of the frontotemporal dementia parkinsonism (FTDP-17) type, in which valine is substituted with methionine residue 337. The aggregation of tau in these transgenic mice satisfies all histological criteria used to identify NFTs common to human neurodegenerative diseases. These mice, therefore, provide a preclinical model for the testing of therapeutic drugs for the treatment of neurodegenerative disorders that exhibit NFTs.
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68
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Matsue H, Matsue K, Kusuhara M, Kumamoto T, Okumura K, Yagita H, Takashima A. Immunosuppressive properties of CD95L-transduced "killer" hybrids created by fusing donor- and recipient-derived dendritic cells. Blood 2001; 98:3465-72. [PMID: 11719389 DOI: 10.1182/blood.v98.12.3465] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Allogeneic immune responses, which are initiated by dendritic cells (DCs) of both donor and host origins, remain a major obstacle in organ transplantation. Presentation of intact major histocompatibility complex (MHC) molecules by allogeneic DCs and allogeneic peptides by syngeneic DCs leads to complex allogeneic immune responses. This study reports a novel strategy designed to suppress both pathways. A stable DC line XS106 (A/J mouse origin) was transfected with CD95L cDNA and fused with splenic DCs purified from allogeneic BALB/c mice. The resulting "killer" DC-DC hybrids: (1) expressed CD95L and MHC class I and class II molecules of both A/J and BALB/c origins, while maintaining otherwise characteristic surface phenotypes of mature DCs; (2) inhibited MHC class I- and class II-restricted mixed leukocyte reactions between the parental strains by triggering apoptosis of alloreactive T cells; and (3) abolished delayed-type hypersensitivity responses of A/J (and BALB/c) mice to BALB/c-associated (and A/J-associated) alloantigens when injected intravenously into A/J (and BALB/c) mice. The onset of graft-versus-host disease in (BALB/c x A/J) F1 hosts receiving A/J-derived hematopoietic cell transplantation was suppressed significantly (P <.001) by killer DC-DC hybrid treatment. These results form both technical and conceptual frameworks for clinical applications of CD95L-transduced killer hybrids created between donor DCs and recipient DCs in the prevention of allogeneic immune responses following organ transplantation.
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69
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Takashima A, Ohta K, Matsushima E, Toru M. The event-related potentials elicited by content and function words during the reading of sentences by patients with schizophrenia. Psychiatry Clin Neurosci 2001; 55:611-8. [PMID: 11737794 DOI: 10.1046/j.1440-1819.2001.00913.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Thought disorder is one of the main symptoms observed in schizophrenia and has been investigated in terms of language dysfunction. The purpose of the present study was to find whether there were any differences in identifying and processing between content (semantic) and function (syntax) words, and to elucidate whether semantic or syntax is more impaired for the schizophrenics. Event-related potentials were recorded in 13 patients with schizophrenia and 14 healthy controls, while they silently read three sets of passages. Event-related potentials were recorded for content words (noun, verb) and function words (auxiliary verb, particle) separately. For the healthy control group, the mean amplitude of P200 for the content word class was greater than for the function word class with fronto-central dominance. In contrast, no such difference was found for the schizophrenics mainly due to the reduction of P200 amplitude of the content words. Larger P200 for the content than the function word class suggests that greater resources were used to identify the content words. Lack of this difference found in patients with schizophrenia suggested that the disturbances in the semantics may be more attributable to the linguistic impairment than those in the syntax.
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Takashima A. [Analysis of mouse model exhibiting neurofibrillary changes]. Rinsho Shinkeigaku 2001; 41:1111-2. [PMID: 12235811] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/26/2023]
Abstract
Dysfunction and filamentous microtubule-binding tau protein are key markers of neurodegenerative pathologies, including the pathology and neural degeneration associated with Alzheimer's disease (AD). Immunocytochemical studies of NFT-bearing neurons showed that NFTs are composed of ubiquitin and phosphorylation-dependent tau. Congo-red birefringency and thioflavin-S reactivity in NFT-bearing neurons also demonstrated that the tau aggregation forms a beta-sheet structure. Discovery of the molecular mechanisms of NFT formation may lead to more insight about events occurring during neurodegeneration. In frontotemporal dementia parkinsonism 17 (FTDP17), genetic studies indicated that tau is a causative gene, and mutation is found in exons and introns of tau gene. A patient who possesses this mutation exhibits pathologically NFT and clinically personality change and cognitive dysfunction. Then, we produced the Tg mice expressing human longest tau with missense mutation V337M. In the present study, neurons of hippocampus and cerebral cortex in our Tg mice showed phosphorylated and ubiquitinated tau aggregations with a beta-sheet structure. This was demonstrated by Congo-red and thioflavin-S positive staining, a histological criterion used to identify NFTs observed in neurodegenerative disorders. The mice also displayed altered behaviors that were associated with NFT formation. Thus, V337M mice provide a first animal model exhibiting altered behavior due to NFTs.
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Morita A, Ariizumi K, Ritter R, Jester JV, Kumamoto T, Johnston SA, Takashima A. Development of a Langerhans cell-targeted gene therapy format using a dendritic cell-specific promoter. Gene Ther 2001; 8:1729-37. [PMID: 11892841 DOI: 10.1038/sj.gt.3301580] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Langerhans cells (LC), which are a skin-specific member of the dendritic cell (DC) family of antigen presenting cells, play critical roles in the initiation of cellular immune responses in the skin. We developed a LC-targeted gene therapy format in this study, aimed at the establishment of in situ protocols for genetic manipulation of LC function. Dectin-2 is a unique C-type lectin that is expressed selectively by DC, including epidermal LC. A 3.2 kb 5' flanking fragment isolated from the mouse dectin-2 gene, termed the dectin-2 promoter (pDec2), exhibited significant transcriptional activities in epidermal-derived DC lines of the XS series, but not in any of the tested non-DC lines. When pDec2-driven luciferase gene (pDec2-Luc) or enhanced green fluorescence protein gene (pDec2-EGFP) was delivered to mouse skin using the gene gun, expression of the corresponding gene product was observed in the epidermal compartment almost exclusively by the IA+ population (ie LC). LC in the gene gun-treated sites showed features of mature DC and they migrated to the draining lymph node, suggesting that LC-targeted gene expression may lead to the development of immune responses. In fact, EGFP-specific cellular immune responses became detectable after gene gun-mediated delivery of pDec2-EGFP plasmid. These results introduce a new concept that LC function can be genetically manipulated in situ by the combination of gene gun-mediated DNA delivery and a DC-specific promoter.
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Abstract
Dendritic cells (DC) are special subsets of antigen presenting cells characterized by their unique abilities to efficiently take up, process, and present various forms of antigens to immunologically naive T cells. Recent advances in the understanding of molecular mechanisms regulating the functions of DC have allowed the investigators to "design" innovative DC-based vaccine formats for the treatment of cancer patients. In this article, we will review the most advanced DC vaccine strategies, focusing on three major areas: a) new ex vivo protocols for DC loading with tumor-associated antigens (TAA), b) genetic approaches to load skin-resident Langerhans cells (LC) with TAA, and c) chemokine-mediated LC entrapment and in situ loading of LC with TAA at the entrapment sites. We believe that these new classes of DC vaccine strategies will soon become applicable to the treatment of patients with malignant tumors.
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Iwakawa T, Tanaka Y, Takashima A. A new galloylglucoside from Cleyera ochnacea DC. Chem Pharm Bull (Tokyo) 2001; 49:1498-9. [PMID: 11724249 DOI: 10.1248/cpb.49.1498] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
A new galloylglucoside, 3-hydroxy-5-methylphenol 1-O-beta-D-(6'-galloyl)glucopyranoside (1) was isolated from Cleyera ochnacea DC. (Theaceae). Its structure was elucidated on the basis of chemical and spectral analysis. Compound 1 showed inhibitory activity against rat cerebellar nitric oxide synthase (NOS).
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Palacino JJ, Murphy MP, Murayama O, Iwasaki K, Fujiwara M, Takashima A, Golde TE, Wolozin B. Presenilin 1 regulates beta-catenin-mediated transcription in a glycogen synthase kinase-3-independent fashion. J Biol Chem 2001; 276:38563-9. [PMID: 11504726 DOI: 10.1074/jbc.m105376200] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Presenilin 1 (PS1) is linked with Alzheimer's disease but exhibits functional roles regulating growth and development. For instance, PS1 binds to beta-catenin and modulates beta-catenin signaling. In the current study, we observed that knockout of PS1 inhibited beta-catenin-mediated transcription by 35%, as shown by a luciferase reporter driven by the hTcf-4 promoter. Overexpressing wild-type PS1 increased beta-catenin-mediated transcription by 37.5%, and overexpressing PS1 with mutations associated with Alzheimer's disease decreased beta-catenin-mediated transcription by 66%. To examine whether regulation of beta-catenin by PS1 requires phosphorylation by glycogen synthase kinase 3beta (GSK 3beta), we examined whether inhibiting GSK 3beta activity overcomes the inhibition of beta-catenin transcription induced by mutant PS1 constructs. Cells expressing wild-type or mutant PS1 were treated with LiCl, which inhibits GSK 3beta, or transfected with beta-catenin constructs that lack the GSK 3beta phosphorylation sites. Neither treatment overcame PS1-mediated inhibition of beta-catenin signaling, suggesting that regulation of beta-catenin by PS1 was not affected by the activity of GSK 3beta. To investigate how PS1 might regulate beta-catenin signaling, we determined whether PS1 interacts with other elements of the beta-catenin signaling cascade, such as the Tcf-4 transcription factor. Coimmunoprecipitation studies showed binding of PS1 and hTcf-4, and examining nuclear isolates indicated that nuclear hTcf-4 was decreased in cells expressing mutant PS1. These data show that PS1 interacts with multiple components of the beta-catenin signaling cascade and suggest that PS1 regulates beta-catenin in a manner independent of GSK 3beta activity.
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75
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Aoki S, Ye Y, Higuchi K, Takashima A, Tanaka Y, Kitagawa I, Kobayashi M. Novel neuronal nitric oxide synthase (nNOS) selective inhibitor, aplysinopsin-type indole alkaloid, from marine sponge Hyrtios erecta. Chem Pharm Bull (Tokyo) 2001; 49:1372-4. [PMID: 11605676 DOI: 10.1248/cpb.49.1372] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Two novel aplysinopsin-type indole alkaloids, 1 and 2, and three known indole alkaloids were isolated from the marine sponge Hyrtios erecta. These compounds exhibited selective inhibitory activity against the neuronal isozyme of nitric oxide synthase (nNOS). Furthermore, new quinolone 7 was also isolated from the same marine sponge. The chemical structures of these new compounds were elucidated on the basis of spectroscopic analysis.
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