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S Tanimukai

Publications and source records attributed to S Tanimukai.

At least 37 records · Page 2Linked to original sources

Simultaneous activation of signals through gp130, c-kit, and interleukin-3 receptor promotes a trilineage blood cell production in the absence of terminally acting lineage-specific factors.

We assessed the biologic role of signaling through gp130, a signal-transducing receptor (R) component, in human hematopoiesis in vitro. Although peripheral blood-derived CD34(+) cells ubiquitously expressed gp130 and interleukin-3 receptor alpha (IL-3Ralpha), IL-6Ralpha was only detected on 80% of these CD34(+) cells. We sorted CD34(+)IL-6R+ or CD34(+)IL-6R- cells and studied the effect on hematopoietic colony formation of signaling through gp130 activated by IL-6 or a combination of IL-6 and recombinant soluble human IL-6R (sIL-6R) in the presence or absence of stem cell factor (SCF ) and/or IL-3. Signals activated by SCF, IL-6, or IL-6/sIL-6R complex alone did not induce significant colony formation. However, a combination of IL-3, SCF, and IL-6/sIL-6R complex dramatically induced many neutrophil (colony-forming unit-granulocyte [CFU-G]), erythroid burst (burst-forming unit-erythrocyte [BFU-E]), erythrocyte-containing mixed (CFU-Mix), and megakaryocyte (CFU-Meg) colony formations when CD34(+)IL-6R- cells were used as the target. CFU-G colony formation induced by the three signals was more evident when CD34(+)IL-6R+ cells were used as the target. This distinct synergistic effect of the three different signals was confirmed by single-cell clone-sorting experiments. Moreover, colony formation (including CFU-G, BFU-E, CFU-Mix, and CFU-Meg) was observed even in the presence of neutralizing antibodies for granulocyte colony-stimulating factor, erythropoietin, and thrombopoietin (c-Mpl), whereas neutralizing antibodies for gp130, IL-6R, IL-3, and SCF partially or completely blocked the synergistic effect. The maturation of neutrophilic, erythroid, and megakaryocytic cells supported by the three signals in serum-free cultures was confirmed by immunostaining using anti-CD66b, antiglycophorin A, antihemoglobin alpha, and anti-CD41 monoclonal antibodies, respectively. In contrast, any two of the three signals were insufficient for effective blood cell production in the absence of maturation factors. These results suggest that simultaneous activation of the three signals through gp130, c-kit, and IL-3R can induce in vitro proliferation and differentiation of trilineage hematopoietic progenitors in the absence of terminally acting lineage-specific factors.

Animals↗

Regional cerebral glucose metabolism in dementia with Lewy bodies and Alzheimer's disease: a comparative study using positron emission tomography.

Regional cerebral metabolic rate of glucose (rCMRglc) was studied in 19 patients with a clinical diagnosis of dementia with Lewy bodies (DLB) and 19 patients with a clinical diagnosis of Alzheimer's disease (AD), using [18F]fluorodeoxyglucose ([18F]FDG) and positron emission tomography (PET). The two groups were matched with age, gender, disease duration and severity of cognitive disturbances. In 'dementia with Lewy bodies' (DLB) patients, when compared with AD patients, significant rCMRglc decreases were distributed in the temporo-parieto-occipital association cortices and the cerebellar hemispheres. In contrast, the medial temporal and cingulate rCMRglc were significantly lower in AD patients than those in DLB patients. These different regional emphases of glucose hypometabolism are consistent with the pathological and neurochemical differences between DLB and AD and explain the different clinical features of the two diseases.

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Functional differences between subpopulations of mobilized peripheral blood-derived CD34+ cells expressing different levels of HLA-DR, CD33, CD38 and c-kit antigens.

We have investigated the functional characteristics of peripheral blood-derived CD34+ cells mobilized by a combination of chemotherapy and G-CSF (mobilized peripheral blood-derived [MPB] CD34+ cells). In this study, subpopulations of MPB CD34+ cells have been directly compared in clonal cultures, long-term cultures with bone marrow (BM) stromal cells, and single-cell cultures. MPB CD34+ cells could be subdivided by expression levels of HLA-DR (DR), CD38, CD33 and c-kit antigens. The majority of MPB CD34+ cells expressed DR and CD38 antigens. In contrast, approximately 60% and 20% of the MPB CD34+ cells expressed CD33 and c-kit antigens, respectively. Interestingly, MPB CD34+ cells can be subdivided into three fractions which express high, low or negative levels of c-kit receptor. All types of committed progenitors were observed in populations of CD34+DR+, CD34+DR-, CD34+CD33-, CD34+CD38+ and CD34+ c-kit(low) cells. Colony forming unit-granulocyte/macrophage was highly enriched in the population of CD34+CD33+ cells, whereas BFU-E was highly enriched in the population of CD34+ c-kit(high) cells. In the population of CD34+CD38- cells, however, a few myeloid progenitors were detected. In addition, limiting dilution analyses clearly showed that the long-term culture-initiating cell (LTC-IC) is enriched in the populations of CD34+DR-, CD34+CD33- and CD34+c-kit-(or low) cells, but very few in CD34+ c-kit(high) cells, and that CD38 antigen is not a useful marker for the enrichment of LTC-IC derived from MPB CD34+ cells. Moreover, single cell clone sorting experiments clearly demonstrated the functional differences between CD34+CD38+ and CD34+CD38- cells as well as CD34+ cells expressing different levels of c-kit receptor. Our results suggest that an immunophenotype of LTC-IC is different between BM-, cord blood- and MPB-derived CD34+ cells and that primitive and committed progenitors existing in these sources may be functionally different.

ADP-ribosyl Cyclase↗

Thrombopoietin augments ex vivo expansion of human cord blood-derived hematopoietic progenitors in combination with stem cell factor and flt3 ligand.

We studied the effects of stem cell factor (SCF) and flt3 ligand (FL) on the ex vivo expansion of human umbilical cord blood (CB)-derived CD34+ cells in combination with various cytokines, including interleukin (IL)-3, IL-6, IL-11, and c-Mpl ligand (thrombopoietin, TPO), in a short-term serum-free liquid suspension culture system. Among the two-factor combinations tested, SCF plus IL-3 most effectively expanded committed progenitor cells, including mixed colony-forming units (CFU-Mix). The expansion efficiency (EE) of FL for each progenitor was inferior to that of SCF in the presence of various cytokines, except TPO. IL-6 significantly increased the EE for granulocyte/macrophage colony-forming units (CFU-GM) obtained with SCF + IL-3 or FL + IL-3. Interestingly, TPO markedly augmented the EE for committed progenitors, including CFU-GM, erythroid burst-forming units (BFU-E), and CFU-Mix, in the presence of SCF + IL-3 or FL + IL-3. The combinations of SCF + IL-3 + TPO + IL-6 or IL-11 maximally stimulated the expansion of committed progenitors. The maximum EE for CFU-GM, BFU-E, and CFU-Mix was respectively 197-fold (day 14), 60-fold (day 7) and 51-fold (day 14). Other combinations of cytokines without IL-3 failed to expand effectively these committed progenitors. Our data demonstrate that it is possible to expand human CB-derived committed progenitors in vitro using SCF or FL with several other cytokines including TPO, and that IL-3 is the key cytokine promoting the expansion of human hematopoietic progenitors in the presence of SCF or FL.

Antigens, CD34↗

Action of human interleukin-4 and stem cell factor on erythroid and mixed colony formation by peripheral blood-derived CD34+ c-kit(high) or CD34+ c-kit(low) cells.

We studied the interaction of interleukin (IL)-4 and other burst-promoting activity (BPA) factors, such as IL-3, granulocyte/macrophage colony-stimulating factor (GM-CSF), IL-9 and stem cell factor (SCF), on erythroid burst-forming unit (BFU-E) and erythrocyte-containing mixed (CFU-Mix) colony formation in serum-free culture. IL-4 alone did not support mixed colony formation in the presence of erythropoietin (Epo). However, IL-4 showed weak but significant BPA when peripheral blood (PB)-derived CD34+c-kit(low) cells were used as the target population. The BPA of IL-4 was much weaker than that of IL-3, which exerted the most potent activity, as previously reported. When CD34+c-kit(high) cells were used as the target, four factors known to have BPA, IL-3, GM-CSF, IL-9 and SCF, could express BPA. In contrast, IL-4, alone failed to support erythroid burst formation. Interestingly, IL-4 showed a remarkable enhancing effect with SCF in promoting the development of erythroid burst and erythrocyte-containing mixed colonies from CD34+c-kit(low) and CD34+c-kit(high) cells. Delayed addition of SCF+Epo or IL-4+Epo to the cultures initiated with either IL-4 or SCF alone clearly demonstrated that SCF was a survival factor for both BFU-E and CFU-Mix progenitors. In contrast, the survival effect of IL-4 was much weaker than that of SCF, and appeared to be more important for progenitors derived from CD34+c-kit(low) cells than for those derived from CD34+c-kit(high) cells. It was recently reported that CD34+c-kit(low) cells represent a more primitive population than CD34+c-kit(high) cells. Taken together, these results suggest that IL-4 helps to recruit primitive progenitor cells in the presence of SCF.

Antigens, CD34↗

Human FLT3 ligand acts on myeloid as well as multipotential progenitors derived from purified CD34+ blood progenitors expressing different levels of c-kit protein.

We studied the effect of human flt3/flk2 ligand (FL) on the proliferation and differentiation of purified CD34+ blood progenitors which express different levels of c-kit protein in clonal cell culture in comparison with that of stem cell factor (SCF). FL alone did not support significant colony formation. However, FL significantly enhanced neutrophil colony (CFU-G) formation in the presence of granulocyte-colony stimulating factor (G-CSF) by peripheral blood (PB)-derived CD34+c-kit- cells which contained a large number of CFU-G. In addition, FL could synergistically increase the number of CFU-G supported by a combination of interleukin (IL)-3 and G-CSF, as did SCF. As we reported previously, SCF showed a significant burst-promoting activity (BPA). In contrast, FL did not exhibit any BPA on PB-derived CD34+c-kithigh cells in which erythroid-burst (BFU-E) was highly enriched. However, FL could synergize with IL-3 or GM-CSF in support of erythrocyte-containing mixed (E-Mix) colony by PB-derived CD34+c-kithigh or low cells in the presence of Epo. Replating of E-Mix colonies derived from CD34+c-kithigh cells supported by IL-3+Epo+SCF yielded more secondary colonies than those supported by IL-3+Epo or IL-3+Epo+FL. When PB-derived CD34+c-kitlow cells which represent a more immature population than CD34+c-kithigh cells were used as the target, number of secondary colonies supported by IL-3+Epo, IL-3+Epo+SCF or IL-3+Epo+FL was comparable. However, the number of lineages expressed in the secondary culture was significantly larger in the primary culture containing IL-3+Epo+FL than in that containing IL-3+Epo. These results suggest that FL not only acts on neutrophilic progenitors, but also on more immature multipotential progenitors.

Antigens, CD↗

Recombinant human c-Mpl ligand (thrombopoietin) not only acts on megakaryocyte progenitors, but also on erythroid and multipotential progenitors in vitro.

To determine the hematopoietic actions of recombinant human c-Mpl ligand (thrombopoietin [TPO]), we studied its effects on the proliferation and differentiation of highly purified CD34+ blood progenitors in plasma-containing and serum-free culture. TPO alone promoted the growth of small megakaryocyte colonies (CFU-Meg) in numbers two to three times greater than those produced by interleukin (IL)-3. The combination of TPO and stem cell factor (SCF) exerted a significant synergistic effect on CFU-Meg formation. In the presence of TPO and IL-3 or granulocyte/macrophage-colony stimulating factor (GM-CSF), a significant number of mixed colonies (CFU-Mix) were observed. The combination of TPO and Epo did not increase the number of CFU-Meg, but did support erythroid-burst (BFU-E) and CFU-Mix colony formation. Interestingly, the combination of TPO with cytokines known to have burst-promoting activity (BPA), including IL-3, GM-CSF, IL-9, and SCF, increased the number of BFU-E and CFU-Mix in the presence of Epo. The BPA of TPO was further investigated by delayed addition of Epo on day 6 after incubation with TPO from day 0. None of the BFU-E or CFU-Mix survived, indicating that TPO acted as a costimulant exclusively for Epo. Moreover, a neutralizing anti-human Mpl receptor polyclonal antibody completely abrogated the BPA of TPO, demonstrating that this effect was mediated through the Mpl receptor. Finally, experiments in single-cell clone sorting and serum-free culture clearly demonstrated that a combination of TPO and Epo directly supported BFU-E and CFU-Mix. These results suggest that TPO acts not only in megakaryocytopoiesis but also in the early stage of hematopoiesis.

Antigens, CD34↗

Effects of SDZ ENA 713, novel acetyl cholinesterase inhibitor, on learning of rats with basal forebrain lesions.

1. The effects of SDZ ENA 713, a novel acetyl cholinesterase inhibitor, on rat learning was studied using a step-down avoidance paradigm. 2. Injection of ibotenic acid into the caudolateral part of the basal forebrain (BF) innervating cholinergic neurons to the cerebral cortex, resulted in an increase in the number of trials required to obtain 300-second-latency, and also a decrease in the latency period after attaining 300-second-latency. 3. It is shown that the BF-lesioned rats are impaired in both acquisition and retention of learning. 4. Intraperitoneal injection of 0.10-0.05 mg/kg/day SDZ ENA 713 to the BF-lesioned rats showed amelioration of the learning impairment, with a decreased number of trials required to obtain 300-second-latency as well as an increase in the latency time after repeated training. 5. These results indicate that SDZ ENA 713 improves acquisition and retention impairment in BF-lesioned rats, and that this drug may be useful for demented patients with cholinergic dysfunction, such as Alzheimer's disease.

Animals↗

Synergistic actions of stem cell factor and other burst-promoting activities on proliferation of CD34+ highly purified blood progenitors expressing HLA-DR or different levels of c-kit protein.

We studied the synergistic effects of stem cell factor (SCF) and other burst-promoting activities (BPAs) such as interleukin-3 (IL-3), granulocyte-macrophage colony-stimulating factor (GM-CSF), or IL-9 on proliferation of human peripheral blood-derived highly purified progenitors. SCF, IL-3, GM-CSF, and IL-9 showed significant BPA when CD34+HLA-DR+ cells were used as the target population. IL-3 exerted the most potent BPA, and GM-CSF supported approximately 40% to 70% of the erythroid burst-forming units that are responsive to IL-3. SCF and IL-9 showed much weaker BPA than that of IL-3 or GM-CSF. Combinations of IL-3 with other BPAs did not show synergistic actions supporting erythroid-burst formation. However, GM-CSF showed a significant additive effect with IL-9 or SCF. When CD34+c-kithigh cells were used as the target, SCF showed a much stronger BPA. Also, a distinct additive effect between SCF and IL-3 or GM-CSF on erythrocyte-containing mixed colony formation was observed. On the other hand, when CD34+c-kitlow cells were used as the target, SCF, IL-3, and GM-CSF could express BPA. In contrast, IL-9 alone failed to support erythroid-burst formation. Because CD34+c-kithigh cells weakly expressed CD34 antigen, these cells appeared to be more mature progenitors than CD34+c-kitlow cells. These results suggest that IL-9 acts on more mature progenitors than those of SCF, IL-3, or GM-CSF and that the primary target of SCF is multipotential progenitors at the very early stage of development.

Animals↗

[A case of atypical presenile dementia].

Kosaka (1993) reviewed 16 cases of slowly progressive presenile cortical dementia thought to be a clinicopathological entity with pathological features characterized by circumscribed lobar atrophy, diffuse neurofibrillary tangles, and calcification of the Fahr type, however, the clilical features of this new entity are not known in the description of detail. We report a patient with atypical presenile dementia which appeared to be consistant with that entity, together with the results of a comprehensive neuropsychological and neuroradiological examination. The patient was a 65-year-old right-handed housewife. At about 58 years of age, she started to lose spontaneity and develop a mild memory disturbance. At age 61 she transiently, experienced hallucinations and delusions. During the subsequent 8 years there was a very slight decline in global intellectual efficiency. In addition, she showed slow but definite progression of language disturbances characterized by anomia and loss of ability to grasp the meaning of words, particularly abstract nouns. She performed poorly on tasks with good sensitivity for detecting frontal lobe dysfunction, such as the Wisconsin Card Sorting Test and the hand sequence test. All other cognitive functions appeared to be relatively well preserved, however moderate dyscalculia was present. There was no socially inappropriate or stereotyped behavior, but the patient lost insight into her disease. The patient's activities of daily living on the ward were self-maintained. An EEG was normal. CT and MRI scans showed circumscribed bilateral fronto-temporal atrophy and bilateral mineralization in the basal ganglia and cerebellar white matter.(ABSTRACT TRUNCATED AT 250 WORDS)

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Neuropathologic changes in the gerbil brain after chronic hypoperfusion.

BACKGROUND AND PURPOSE: An animal model has been developed to elucidate the pathological changes in brain cytoskeletal proteins during chronic hypoperfusion. METHODS: Newly designed coiled clips were placed around both carotid arteries of Mongolian gerbils (n = 10) to cause stenosis without occlusion. Those gerbils showing impaired learning ability by the passive avoidance paradigm were killed for neuropathologic study after 12 weeks. RESULTS: The brains showed ventricular dilatation, cortical atrophy, and rarefaction of the white matter. Immunoreactivity to anti-microtubule-associated protein 2 antibody in the cerebral cortex and the hippocampus was diminished, indicating dendritic changes of neurons. In the thalamic axonal regions, staining with anti-neurofilament 200K protein antibody was increased, suggesting increased amounts of neurofilament proteins or increased phosphorylation of the protein. Increased immunoreactivity to anti-glial fibrillary acidic protein antibody was observed in a wedge-shaped configuration, corresponding to the border zone of perfusion by small vessels. CONCLUSIONS: These findings suggest that changes in the cytoskeletal proteins in dendrites, axons, and glial cells may cause neuronal death under conditions of chronic cerebral hypoperfusion.

Animals↗

Buffy coat from families of Alzheimer's disease patients produces intracytoplasmic neurofilament accumulation in hamster brain.

Buffy coat of three members from a family with Alzheimer's disease was inoculated into hamster brains. Eighteen months after the inoculation, all experimental animals were sacrificed for the neuropathological study. Hematoxylin-eosin staining showed no gross vacuolar degeneration, or neuronal loss in the cortex. The spongiform degeneration was minimum. Immunostaining with antibodies against neurofilament 200 kDa subunit protein revealed massive immuno-positive intracytoplasmic inclusion bodies within neurons of the brainstem nuclei. By electron microscopy, the intracytoplasmic inclusion body was shown to be composed of proliferated 10 nm neurofilaments. The intra-cytoplasmic neurofilament proliferation was observed with the hamsters inoculated with the buffy coat from Alzheimer's disease patients as well as an apparently normal member of the family.

Alzheimer Disease↗

Immunohistochemical study of microtubule-associated protein 2 and ubiquitin in chronically aluminum-intoxicated rabbit brain.

Experimental neurofibrillary change was produced in rabbit brain by daily subcutaneous aluminum tartrate injection for 40 days. The production of experimental neurofibrillary changes was confirmed by immunostaining with antibodies against neurofilament triplet proteins and the brain tissue was studied immunohistochemically with antibodies against microtubule-associated protein (MAP) 2 and ubiquitin. The hippocampal neurons of the chronically aluminum-intoxicated rabbit brain showed diminished staining of dendrites by anti-MAP2 antibody. The length of anti-MAP2-positive dendrites in hippocampus was significantly shorter than that of the control brain. In the cortex somata of a subset of pyramidal neurons were intensively stained by anti-MAP2 antibody, while the MAP2 immunoreactivity of distal dendrites was diminished. The immunostaining by anti-ubiquitin antibody revealed the positive staining of the neurons bearing experimental neurofibrillary changes in the lower brain stem nuclei. It is speculated that MAP2 dislocation and ubiquitination are accompanying phenomena of the production of experimental neurofibrillary changes in chronically aluminum-intoxicated rabbit brains.

Aluminum↗

Study of cytoskeletal proteins in fibroblasts cultured from familial Alzheimer's disease.

Cytoskeletal proteins of the cultured fibroblasts obtained from Alzheimer's disease patients were studied. Western blotting studies of tubulin, actin, and vimentin showed no difference between Alzheimer and the control fibroblasts. Western blotting studies of vimentin revealed five partial degradation products in 50 K-57 K Da. molecular size region, but no difference in the degradation pattern was noticed between Alzheimer and the control fibroblasts. The size of fodrin molecule, however, was quite different between Alzheimer and the control fibroblasts. Comparing the molecular size of fodrin purified from the bovine brain, it is concluded that fodrin in Alzheimer fibroblasts is not degraded, while significant amount of fodrin in the control fibroblasts is partially degraded resulting in the smaller size of the 160 K and 200 K Da. molecular weight products.

Actins↗

Characterization of intracytoplasmic neurofilament accumulation in hamster brain caused by Alzheimer buffy coat inoculation: comparison with experimental neurofibrillary changes produced by aluminum intoxication.

Neurofilament accumulation was produced in neuronal perikarya of the lower brain stem nuclei in the hamster brain by inoculating buffy coat from a patient with Alzheimer's disease. The abnormally proliferated neurofilament was characterized by immunostaining and electron microscopy. The intracytoplasmic neurofilament accumulation was positively stained with anti-tau and anti-ubiquitin, but not with antibody against paired helical filaments. Experimental neurofibrillary changes were produced in the rabbit brain by aluminum injection, and the proliferated neurofilaments in the rabbit brain were compared with those in the hamster brain inoculated with Alzheimer buffy coat. The results indicate that the long pathological process in the hamster brain is triggered by Alzheimer's buffy coat inoculation which results in intracytoplasmic accumulation of modified neurofilaments.

Aluminum↗

Clinical diagnosis of dementia with Lewy bodies in a Japanese dementia registry.

We found 15 patients with dementia with Lewy bodies (DLB) and 232 patients with Alzheimer's disease (AD) among 327 consecutive patients with mild to moderate dementia in a Japanese dementia registry, using the clinical criteria of the Consortium on DLB International Workshop. The percentage of females was significantly lower in DLB than in AD (p < 0.01), while age at examination, Mini-Mental State Examination score and duration of cognitive symptoms were comparable between the two diseases. Eight of the 15 DLB patients (53%) had spontaneous parkinsonism, which was observed in 6 of the 232 AD patients (2.6%). Visual hallucinations were reported by 11 of the 15 DLB patients (73%) and 8 of the 232 AD patients (3.4%). Cognitive fluctuation was positive in 13 of the 15 DLB patients (87%). We found two types of episodic cognitive deterioration: one was characterized by pronounced disturbances of attention and alertness (inattention type), and the other was characterized by marked and bizarre disturbances of orientation in time and places, and misidentification of persons (disorientation type). Systematized delusion was observed in 8 DLB patients, and 5 patients showed neuroleptic sensitivity. Patients with DLB have a unique dementia syndrome even in the stage of mild to moderate cognitive impairments. Further studies are recommended to establish diagnosis, treatment and management.

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A study of remote memory impairment in Alzheimer's disease by using the family line test.

We evaluated remote autobiographical memory impairment in 25 patients with probable Alzheimer's disease (AD) and 25 sex-, age- and education-matched healthy subjects by using a newly developed, highly effective assessment tool for remote memory, the Family Line Test (FLT). The FLT yields a total score, scores for 3 lifetime periods and the duration of remote memory impairment. In the patients with AD, the total score was significantly lower and the duration of remote memory impairment was significantly longer than in the healthy controls. A prominent temporal gradient in remote memory impairment was documented in the patients with AD. The total FLT score and duration of remote memory impairment correlated with recent memory and general cognitive dysfunctions.

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Features of regional cerebral glucose metabolism abnormality in corticobasal degeneration.

We studied regional cerebral glucose metabolism in 15 patients with a clinical diagnosis of corticobasal degeneration (CBD), 15 patients with probable Alzheimer's disease (AD), and 15 healthy controls for 19 brain regions. Asymmetry in regional glucose metabolism was found in the central and frontal cortices in patients with CBD as compared with either the normal controls or the patients with AD. Regional glucose metabolism in CBD patients was significantly lower in the paracentral and superior parietal areas and thalamus than in patients with AD. Relative glucose metabolism in patients with CBD was significantly higher in the posterior cingulate, medial temporal and basal frontal areas, and significantly lower in the paracentral and superior parietal areas than in those with AD. These features of regional glucose metabolic abnormality in CBD may correspond to neurological and cognitive disturbances peculiar to CBD.

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