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Get PDFMultiple system atrophy (MSA) is a sporadic neurodegenerative disease manifested clinically by progressive ataxia, parkinsonism, and autonomic dysfunction. Its cause is unknown, and there is no curative therapy. α-synuclein is an important protein forming aggregations called glial cytoplasmic inclusions (GCIs) in oligodendroglia; these aggregations are considered important in MSA pathogenesis. Overexpression of the human α-synuclein gene in mice induces the formation of GCI-like aggregations in oligodendrocytes, leading mice to exhibit neurological signs similar to those in MSA patients. However, previous studies have excluded mutations within the coding region of the α-synuclein gene in MSA patients. To determine whether alteration in the expression level of the α-synuclein gene is associated with MSA pathogenesis, we used TaqMan quantitative PCR assay to analyze the α-synuclein gene copy number in patients’ genomes. We also used quantitative RT-PCR and in situ hybridization to analyze α-synuclein mRNA expression in MSA patients’ brain tissues. We found no alteration in the α-synuclein gene copy number in the patients’ genomes (n = 50). Quantitative analysis for α-synuclein mRNA by the TaqMan method showed that α-synuclein mRNA levels were comparable between control (n = 3) and MSA (n = 3) cerebella. On in situ hybridization, the number of neurons with α-synuclein mRNA expression was no greater in the cerebella of MSA patients (n = 3) than in the controls (n = 3). However, GCIs were seen in these MSA specimens on immunohistochemistry for α-synuclein. These results suggest that α-synuclein gene expression is not the fundamental cause of MSA.departmental bulletin pape
Get PDFThe purpose of this study was to determine the effect of aging on the tactile and pain sensitivity, and the factors influencing threshold change in the oral mucosa using Semmes-Weinstein Pressure Aesthesiometer. The touch and pain thresholds of 81 healthy elderly (40 males and 41 females, 77 ± 4.5 years) were compared with those of 58 young volunteers (27 males and 31 females, 27 ± 2.5 years). We measured the pain thresholds, the touch thresholds, PCR score and amount of salivation. Semmes-Weinstein Pressure Aesthesiometer was applied to 9 points in the oral region and 4 points in the hands; the dorsum manus, the palma manus, the incisive papilla, the palatal mucosa, the buccal mucosa, the margin of the tongue, and the dorsum of the tongue. Elderly subjects showed significantly higher touch thresholds than those of young subjects in the dorsum manus, the palma manus, the buccal mucosa, the incisive papilla, the margin of the tongue, and the dorsum of the tongue (P < 0.05). The pain thresholds of elderly subjects were significantly lower than those of young subjects in the buccal mucosa and the palatal mucosa (P < 0.05). The touch threshold was not influenced by the smoking habit, denture and amount of salivation. The pain threshold was influenced by the denture on the palate.departmental bulletin pape
Get PDFA porous hydroxyapatite/collagen composite (HAp/Col) was developed that consists of hydroxyapatite nanocrystals and atelocollagen. In this study, cylindrical (diameter: 5 mm, height: 3 mm) porous HAp/Col implants with different pore sizes (diameter: 160 or 290 µm) were prepared, and thei nfluences of pore size and implanted volume were evaluated using a rabbit bone defect model. In the implant groups, one or three (diameter: 5 mm, total height: 9 mm) implants were transplanted into bone holes created in the anteromedial site of the proximal tibiae, while a group without implantation was used as a control. Histological observation revealed that at two weeks after implantation, bone formation was initiated not only from the periosteum but in regions where the implants bordered on bone marrow. At four weeks, bone formation expanded from the marrow cavity side into the center of the implants, particularly in those implants with large pores. At twelve weeks, four implant groups showed repair of cortical defects and implant absorption, which was thought to be the result of natural bone remodeling mechanisms.The control group showed bone formation developed from the periosteum without bone induction in the marrow cavity, and at four weeks, the bone hole was almost healed. pQCT analysis revealed that the expansion rates of bone tissue were higher in the large-pore implant groups than in the small-pore groups. These data demonstrate the osteoconductivity of porous HAp/Col and the importance of its porous structure.departmental bulletin pape
Get PDFBackground: Gamma-delta (γδ) T cells regulate immune responses at mucosal surfaces. Whether they can modify allergen-induced early (EAR) and late airway responses (LAR) is unknown. Objective: We have tested the hypothesis that the γδ T cells enhance allergen-induced airway responses in mice. Methods: BALB/c wild-type (WT) mice and γδ T cell-deficient (γδ T-cell KO) mice were sensitized by intraperitoneal injection of ovalbumin (OVA) on days 1 and 15, immunized with 1% OVA aerosol on days 29-31, and challenged with 5% OVA or saline on day 33. Enhanced pause (Penh) was measured and BAL fluid was collected after challenge. Serum IgE was measured before challenge. The percentage of interleukin (IL)-4 and interferon (IFN)-γ producing T cells in splenocytes from sensitized animals was determined by flow cytometry. Results: Both EAR and LAR were observed in OVA-challenged WT mice. LAR but not EAR was inhibited in OVA-challenged γδ T-cell KO mice. γδ T-cell KO mice showed less eosinophilia in BALF and serum OVA-specific IgE. In the sensitization period, the percentage of IFN-γ producing αβ T cell in γδ T-cell KO mice was higher than that in WT mice. Conclusion: γδ T cells enhance LAR and airway inflammation but not EAR in this model of asthma.departmental bulletin pape
Get PDFMasticatory performance of denture wearers was compared with that of the normal subjects by analyzing the behavior of the mechanical properties of the bolus. The index of the ability to comminute bolus was described as the total number of masticatory strokes until swallowing and therefore this was chosen as the first index. Principal Component Analysis (PCA) on the data of six parameters; 80% energy, elasticity, viscosity, hardness, adhesiveness, and cohesiveness, indicated that the cohesiveness was independent of the other parameters and should be evaluated as the second index of the ability to dilute bolus with saliva. Two factor scores of the other parameters were calculated using the standardized scoring coefficient obtained from PCA and factor analysis on the data of the normal subjects, which realized to compare two groups on the same plane of factor scores. The movement of factor scores on the factor plane would indicate the total behavior of mechanical properties of bolus and was chosen as the third index of the ability to knead bolus. Triangle Diagram (TD) was completed by using these three indices. On the TD, all the subjects were lower level at least in one index than the normal subjects in all the foods.departmental bulletin pape
Get PDFIt has become clear that foods crushing is performedin the circumscribed region between functionalcusps, that is, at "the main occluding area".However, it is not established to evaluate this areaobjectively.The purpose of this study was to establish thepositional evaluation of the main occluding areaquantitatively and evaluate the positional changedepending on the age with this method. The subjectswere fifteen adults and ten adolescents whohad no stomatognathic disorder. TemporaryStopping was used as test material in this study.In order to analyze the position of the mainoccluding area, the projected centroid coordinate ofthe test material was calculated and projectedonto the reference axis. It was possible to quantitativelyevaluate positional changes of the mainoccluding area depending on growth process. As aresult, the main occluding areas of the adultswere significantly posterior to those of the adolescentsand tended to be more stable. There was asignificant difference in the occlusal contant areabetween two groups. The occlusal contact area hadgreat influence on the stability of the main occludingarea. However, besides occlusal contact area,there might be other factors which stabilized themain occluding area.departmental bulletin pape
Get PDFBackground: UDP-N-acetylglucosamine 2-epimerase/N-acetylmannosamine kinase (GNE) is a key molecule in the pathogenesis of distal myopathy with rimmed vacuoles (DMRV) and hereditary inclusion body myopathy (HIBM) and almost all such patients have some mutations in GNE. However, subcellular localization of GNE and the mechanism of muscular damage have not been clarified. Methods: A rabbit polyclonal antibody for GNE was prepared. Immunohistochemistry was performed using anti-GNE and anti-nuclear protein antibodies. Western blotting with subcellular fractionated proteins was performed to determine subcellular localization of GNE. The sizes of myonuclei were quantified in muscle biopsies from patients with DMRV and amyotrophic lateral sclerosis (ALS). Results: In DMRV muscles, immunohistochemistry identified GNE in sarcoplasm and specifically in myonuclei and rimmed vacuoles (RV). Nuclear proteins were also found in RVs. Immunohistochemistry showed colocalization of GNE and emerin in C2C12 cells.Western blotting revealed the presence of GNE in nuclear fractions of human embryonic kidney (HEK) 293T cells. The mean size of myonuclei of DMRV was significantly larger than that of ALS. Conclusion: GNE is present in myonuclei near nuclear membrane. Our results suggest that myonuclei are involved in RV formation in DMRV, and that mutant GNE in myonuclei seems to play some role in this process.departmental bulletin pape
Cre complementation with variable dimerizers for inducible expression in neurons
Get PDFCre complementation is a process of reconstitution of the activity of DNA recombinase by noncovalent association of multiple segments of Cre recombinase, which are enzymatically inactive by themselves. Cre complementation is potentially useful in restriction of Cre activity in a specific subset of cells, with temporal regulation, by limiting overlap in expression of Cre fragments. We analyzed the efficiency of Cre complementation using three different dimerizing modules in the context of non-neuronal cells and found differential Cre complementation efficiency. We further tested the efficiency of Cre complementation in primary hippocampal neurons derived from transgenic mice harboring a reporter gene flanked by loxP sites and confirmed differential activity of dimerization modules in Cre-dependent recombination of the transgene. These results suggest possible application of dimerizer-based Cre complementation in inducible expression/inactivation of target genes in a specific subset of neurons in the complex environment of nervous tissue in vivo.journal articl
Get PDFObjective: Phospholipase A2 (PLA2) is a key enzyme in arachidonic acid metabolism, which is involved in the maintenance of biological homeostasis and the onset of various diseases. The immunohistochemical localization of PLA2 in the nasal mucosa has not been reported, even though the presence of messenger RNA of PLA2 has been demonstrated in the human nasal brush sample. The present study was designed to determine the localization of PLA2s in the nasal cavity. Methods: The immunohistochemichal localization of secretory PLA2 (sPLA2) and cytosolic PLA2 (cPLA2) in the nasal mucosa was studied using adult guinea pig. Results: Both sPLA2 and cPLA2 were localized in the nasal gland as well as the respiratory epithelium, and not in the surrounding vascular endothelial cells, olfactory gland, olfactory epithelium or submucosal tissue. Conclusion: Our data provide the first convincing evidence that both sPLA2 and cPLA2 are significantly expressed in the nasal gland and the respiratory epithelium, and are suggested to regulate the function of the nasal mucosa, such as bactericidal, Na secretion, and allergic response.departmental bulletin pape
Get PDFPurpose: Pancreatic cancer is characterized by an extremely poor prognosis due to the aggressive disease course and lack of effective therapeutic intervention. IĸB kinase (IKK), a central kinase for nuclear factor-ĸB (NF-ĸB) activation, is often constitutively activated in pancreatic cancer cells, playing a crucial role in the malignant phenotype and resistance to anti-cancer agents. This study explored how specific inhibition of IKKβ suppresses oncogenic proliferation of pancreatic cancer cells. Experimental Design: We employed two different approaches, RNA interference-mediated depletion of IKKβ (IKKβi) and use of a novel molecularly designed IKKβ inhibitor IMD-0354 to investigate the effects on the in vitro and in vivo growth and apoptotic response of pancreatic cancer cells. Results: IKKβi and IMD-0354 efficiently suppressed constitutive NF-ĸB activity and the growth of pancreatic cancer cells in monolayer and soft agar. IMD-0354 induced Annexin V expression, a typical apoptotic cell response. Notably, daily administration of IMD-0354 significantly suppressed tumor growth in NOD/SCID/γcnull (NOG) mice without any deleterious side effect. Conclusions: These results identify IKKβ as an attractive molecular target for pancreatic cancer therapy.departmental bulletin pape