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1.
Eur J Dent Educ ; 22(3): e327-e336, 2018 Aug.
Article in English | MEDLINE | ID: mdl-29091328

ABSTRACT

INTRODUCTION: The aim of this study was to assess the effectiveness of improving the attitude of dental students towards the use of a full-body patient simulation system (SIMROID) compared to the traditional mannequin (CLINSIM) for dental clinical education. MATERIALS AND METHODS: The participants were 10 male undergraduate dental students who had finished clinical training in the university hospital 1 year before this study started. They performed a crown preparation on an upper pre-molar tooth using SIMROID and CLINSIM as the practical clinical trials. The elapsed time for preparation was recorded. The taper of the abutment teeth was measured using a 3-dimensional shape-measuring device after this trial. In addition, a self-reported questionnaire was collected that included physical pain, treatment safety and maintaining a clean area for each simulator. Qualitative data analysis of a free format report about SIMROID was performed using text mining analysis. This trial was performed twice at 1-month intervals. RESULTS: The students considered physical pain, treatment safety and a clean area for SIMROID significantly better than that for CLINSIM (P < .01). The elapsed time of preparation in the second practical clinical trial was significantly lower than in the first for SIMROID and CLINSIM (P < .01). However, there were no significant differences between the abutment tapers for both systems. For the text mining analysis, most of the students wrote that SIMROID was similar to real patients. CONCLUSION: The use of SIMROID was proven to be effective in improving the attitude of students towards patients, thereby giving importance to considerations for actual patients during dental treatment.


Subject(s)
Attitude of Health Personnel , Dental Care , Manikins , Robotics , Simulation Training , Clinical Competence , Crowns , Dentist-Patient Relations , Humans , Japan , Male , Patient Safety , Self Report , Students, Dental , Surveys and Questionnaires , Young Adult
2.
Am J Physiol Cell Physiol ; 308(10): C848-55, 2015 May 15.
Article in English | MEDLINE | ID: mdl-25788575

ABSTRACT

Effects of macrophage on the responses of soleus fiber size to hind limb unloading and reloading were studied in osteopetrotic homozygous (op/op) mice with inactivated mutation of macrophage colony-stimulating factor (M-CSF) gene and in wild-type (+/+) and heterozygous (+/op) mice. The basal levels of mitotically active and quiescent satellite cell (-46 and -39% vs. +/+, and -40 and -30% vs. +/op) and myonuclear number (-29% vs. +/+ and -28% vs. +/op) in fibers of op/op mice were significantly less than controls. Fiber length and sarcomere number in op/op were also less than +/+ (-22%) and +/op (-21%) mice. Similar trend was noted in fiber cross-sectional area (CSA, -15% vs. +/+, P = 0.06, and -14% vs. +/op, P = 0.07). The sizes of myonuclear domain, cytoplasmic volume per myonucleus, were identical in all types of mice. The CSA, length, and the whole number of sarcomeres, myonuclei, and mitotically active and quiescent satellite cells, as well as myonuclear domain, in single muscle fibers were decreased after 10 days of unloading in all types of mice, although all of these parameters in +/+ and +/op mice were increased toward the control values after 10 days of reloading. However, none of these levels in op/op mice were recovered. Data suggest that M-CSF and/or macrophages are important to activate satellite cells, which cause increase of myonuclear number during fiber hypertrophy. However, it is unclear why their responses to general growth and reloading after unloading are different.


Subject(s)
Macrophages/pathology , Muscle Fibers, Skeletal/pathology , Satellite Cells, Skeletal Muscle/metabolism , Animals , Disease Models, Animal , Hypertrophy/metabolism , Hypertrophy/prevention & control , Male , Mice , Muscle, Skeletal/metabolism , Muscular Atrophy/metabolism , Myoblasts/metabolism , Osteopetrosis/metabolism
3.
J Oral Rehabil ; 40(4): 239-46, 2013 Apr.
Article in English | MEDLINE | ID: mdl-23398635

ABSTRACT

Parafunctional habits, such as prolonged clenching and bruxism, have been associated with dysfunctional overloading in the temporomandibular joint (TMJ). In this study, stress distributions in the TMJ were analysed during prolonged clenching, using three-dimensional finite element (FE) models of the TMJ with and without disc displacement. The aim of this study was to investigate stress distribution of the cartilaginous tissues in the TMJ with and without disc displacement. Finite element models were developed on the basis of magnetic resonance images from two subjects with and without anterior disc displacement. Condylar movements recorded during a 5-min clenching were used as the loading condition for stress analysis. In the asymptomatic model, the highest von Mises stresses were located in the lateral area (4·91 MPa) of the disc surfaces, and after 5-min clenching, the higher stresses were still located at the lateral area (3·65 MPa). In all the cartilaginous tissues, 30-50% of stress reduction occurred during 5-min clenching. In contrast, the von Mises stress in the cartilaginous tissues of the symptomatic model with disc displacement was markedly lower, compared with the asymptomatic model. However, in the condylar cartilage, stress relaxation during clenching was not recognised. Furthermore, relatively high stresses were observed in the retrodiscal tissues throughout clenching. The present results indicate that disc position could be involved in the stress distribution of the TMJ components during prolonged clenching.


Subject(s)
Finite Element Analysis , Joint Dislocations/physiopathology , Muscle Contraction/physiology , Temporomandibular Joint Disc/physiopathology , Temporomandibular Joint Disorders/physiopathology , Temporomandibular Joint/physiopathology , Adult , Algorithms , Biomechanical Phenomena , Cartilage, Articular/pathology , Cartilage, Articular/physiopathology , Computer Simulation , Elastic Modulus , Female , Friction , Humans , Imaging, Three-Dimensional/methods , Joint Dislocations/pathology , Magnetic Resonance Imaging , Mandibular Condyle/pathology , Mandibular Condyle/physiopathology , Masticatory Muscles/physiopathology , Models, Biological , Stress, Mechanical , Temporal Bone/pathology , Temporal Bone/physiopathology , Temporomandibular Joint/pathology , Temporomandibular Joint Disc/pathology , Temporomandibular Joint Disorders/pathology , Young Adult
4.
Bone Marrow Transplant ; 45(5): 912-8, 2010 May.
Article in English | MEDLINE | ID: mdl-19802024

ABSTRACT

Chronic GVHD (cGVHD) of the liver is an important cause of morbidity and mortality after allogeneic hematopoietic stem cell transplantation (allo-SCT). It is characterized by the destruction of bile duct epithelium followed by progressive cholestasis, which resembles primary biliary cirrhosis (PBC) clinically and histologically. Bezafibrate (BF) is a widely used agent for hyperlipidemia that is also effective in ursodeoxycholic acid (UDCA)-resistant PBC patients. The putative mechanism in cholestasis is that BF upregulates the expression of phosphatidylcholine flippase on bile canaliculi, facilitates phospholipid output into bile and relieves bile duct damage caused by hydrophobic bile salts. Therefore, the effects of BF in patients with cGVHD of the liver were investigated. Of 87 patients with cGVHD who survived more than 100 days after SCT, 8 were given BF to treat liver cGVHD because of a poor therapeutic response to UDCA and immunosuppressants. The serum alkaline phosphatase (ALP) and gamma-glutamyl transpeptidase (gamma-GTP) levels decreased significantly within 1 month after initiation of BF therapy compared with those before BF therapy in all patients (ALP, 964.9.0+/-306.9 to 597.8+/-102.5 IU/l, P=0.012; gamma-GTP, 528.8+/-299.0 to 269.0+/-119.9 IU/l, P=0.012). BF was effective in patients with liver cGVHD, including UDCA-resistant patients. BF could be a novel therapeutic option for liver cGVHD that helps to preserve normal immunity with the antileukemic effect of cGVHD.


Subject(s)
Bezafibrate/therapeutic use , Graft vs Host Disease/therapy , Hematopoietic Stem Cell Transplantation/adverse effects , Liver Diseases/therapy , Adult , Chronic Disease , Female , Graft vs Host Disease/complications , Graft vs Host Disease/diagnosis , Humans , Liver Diseases/complications , Liver Diseases/diagnosis , Male , Middle Aged , Retrospective Studies , Transplantation, Homologous
5.
Ann Oncol ; 21(4): 833-841, 2010 Apr.
Article in English | MEDLINE | ID: mdl-19889619

ABSTRACT

BACKGROUND: The F-box protein S-phase kinase-associated protein 2 (Skp2) positively regulates the G1-S transition by promoting degradation of the cyclin-dependent kinase inhibitor p27(kip1) (p27). Recent evidence has indicated an oncogenic role of Skp2 in not only carcinogenesis but also lymphomagenesis. MATERIALS AND METHODS: Clinicopathologic features and immunohistochemical expression of Skp2 and p27 were studied retrospectively in 671 patients treated with cyclophosphamide, vincristine, doxorubicin and prednisolone (CHOP) or cyclophosphamide, vincristine, doxorubicin and prednisolone plus rituximab (R-CHOP). The median follow-up periods were 43.2 months in the CHOP group (n = 425) and 24.0 months in the R-CHOP group (n = 246). RESULTS: High Skp2 or low p27 expression correlated significantly with poor overall survival (OS) and progression-free survival (P < 0.001) in both treatment groups. The prognostic value of Skp2 or p27 expression was independent of the parameters included in the International Prognostic Index by multivariate analysis. Patients with high Skp2 expression in combination with low p27 expression showed the worst survival. CONCLUSIONS: Addition of rituximab to the CHOP regimen did not provide a beneficial outcome to patients with diffuse large B-cell lymphoma with high Skp2 expression and low p27 expression. Skp2 and p27 may be useful prognostic markers in the rituximab era.


Subject(s)
Antibodies, Monoclonal/therapeutic use , Cyclin-Dependent Kinase Inhibitor p27/metabolism , Lymphoma, Large B-Cell, Diffuse/diagnosis , Lymphoma, Large B-Cell, Diffuse/drug therapy , S-Phase Kinase-Associated Proteins/metabolism , Adult , Aged , Aged, 80 and over , Antibodies, Monoclonal/administration & dosage , Antibodies, Monoclonal, Murine-Derived , Antineoplastic Agents/administration & dosage , Antineoplastic Agents/therapeutic use , Antineoplastic Combined Chemotherapy Protocols , Biomarkers, Tumor/metabolism , Cyclophosphamide , Doxorubicin , Female , Humans , Lymphoma, Large B-Cell, Diffuse/metabolism , Lymphoma, Large B-Cell, Diffuse/mortality , Male , Middle Aged , Prednisone , Prognosis , Retrospective Studies , Rituximab , Survival Analysis , Vincristine , Young Adult
6.
Parasitology ; 134(Pt 12): 1823-30, 2007 Nov.
Article in English | MEDLINE | ID: mdl-17599782

ABSTRACT

Neobenedenia girellae, a capsalid monogenean, is a significant pathogen due to both its ability to cause high mortality in fishes and its low host specificity. Established control methods have both advantages and disadvantages. Biological control measures with no unfavourable effects on the environment should be incorporated into the control strategy. The response of N. girellae oncomiracidia to brightness and black-and-white contrast was investigated to search for an alternative approach of disease prevention or control. Japanese flounder, Paralichthys olivaceus (Paralichthyidae), were exposed to oncomiracidia in an aquarium divided into areas of different brightness ( approximately 1.3, 41.3 and 138.0 lux). The number of parasites on the fish group reared in 138.0 lux was significantly higher than on those reared in the lower brightness levels. Thus, the fish tended to be more vulnerable to infection by N. girellae under brighter conditions. Challenge trials using host fish mucus and whole live fish were established to detect the response by oncomiracidia to black-and-white contrast on a white versus a black background. Markedly more N. girellae oncomiracidia attached to black-painted areas and dark-coloured fish (normal spotted halibut, Verasper variegatus (Pleuronectidae) compared with white-painted areas and light-coloured fish (mal-coloured V. variegatus) on a white-coloured background. On a black-coloured background, more N. girellae oncomiracidia tended to attach to white-painted areas and light-coloured fish. Thus, black-and-white contrast is considered important for host finding by N. girellae oncomiracidia. The simplicity of the positive phototactic behaviour and the response to black-and-white contrast may lead to the development of a simple, practical and inexpensive method to control N. girellae outbreaks.


Subject(s)
Ectoparasitic Infestations/veterinary , Fish Diseases/parasitology , Flounder/parasitology , Host-Parasite Interactions/physiology , Lighting , Trematoda/physiology , Trematode Infections/veterinary , Animals , Ectoparasitic Infestations/parasitology , Mucus/parasitology , Population Density , Trematode Infections/parasitology
7.
Am J Physiol Cell Physiol ; 293(1): C35-44, 2007 Jul.
Article in English | MEDLINE | ID: mdl-17182729

ABSTRACT

Effects of 14 days of hindlimb unloading or synergist ablation-related overloading with or without deafferentation on the fiber cross-sectional area, myonuclear number, size, and domain, the number of nucleoli in a single myonucleus, and the levels in the phosphorylation of the ribosomal protein S6 (S6) and 27-kDa heat shock protein (HSP27) were studied in rat soleus. Hypertrophy of fibers (+24%), associated with increased nucleolar number (from 1-2 to 3-5) within a myonucleus and myonuclear domain (+27%) compared with the preexperimental level, was induced by synergist ablation. Such phenomena were associated with increased levels of phosphorylated S6 (+84%) and HSP27 (+28%). Fiber atrophy (-52%), associated with decreased number (-31%) and domain size (-28%) of myonuclei and phosphorylation of S6 (-98%) and HSP27 (-63%), and with increased myonuclear size (+19%) and ubiquitination of myosin heavy chain (+33%, P > 0.05), was observed after unloading, which inhibited the mechanical load. Responses to deafferentation, which inhibited electromyogram level (-47%), were basically similar to those caused by hindlimb unloading, although the magnitudes were minor. The deafferentation-related responses were prevented and nucleolar number was even increased (+18%) by addition of synergist ablation, even though the integrated electromyogram level was still 30% less than controls. It is suggested that the load-dependent maintenance or upregulation of the nucleolar number and/or phosphorylation of S6 and HSP27 plays the important role(s) in the regulation of muscle mass. It was also indicated that such regulation was not necessarily associated with the neural activity.


Subject(s)
Cell Nucleolus/metabolism , Heat-Shock Proteins/metabolism , Muscle, Skeletal/metabolism , Muscular Atrophy/metabolism , Muscular Diseases/metabolism , Neoplasm Proteins/metabolism , Ribosomal Protein S6/metabolism , Animals , Cell Nucleolus/pathology , Disease Models, Animal , Electromyography , HSP27 Heat-Shock Proteins , Hindlimb Suspension , Hypertrophy , Male , Muscle Denervation , Muscle Fibers, Skeletal/metabolism , Muscle Fibers, Skeletal/pathology , Muscle Strength , Muscle, Skeletal/innervation , Muscle, Skeletal/pathology , Muscle, Skeletal/physiopathology , Muscular Atrophy/pathology , Muscular Atrophy/physiopathology , Muscular Diseases/pathology , Muscular Diseases/physiopathology , Myosin Heavy Chains/metabolism , Phosphorylation , Protein Processing, Post-Translational , Rats , Rats, Wistar , Ubiquitin/metabolism
8.
Life Sci ; 79(7): 686-94, 2006 Jul 10.
Article in English | MEDLINE | ID: mdl-16540123

ABSTRACT

Effects of gravitational unloading or loading on the growth and development of hindlimb bones were studied in rats. Male Wistar rats were hindlimb-unloaded or loaded at 2-G from the postnatal day 4 to month 3. The morphology and mineral content of tibia and fibula, as well as the mobility of ankle joints, were measured at the end of 3-month suspension or loading, and 1, 2, and 3 months after ambulation recovery. Growth-related increases of bone weight and mineral density were inhibited by unloading. But they were gradually recovered toward the control levels, even though they were still less than those in the age-matched controls after 3 months. None of the parameters were influenced by 2-G loading. However, here we report that chronic unloading causes abnormal morphological development in hindlimb bone of growing rats. Irreversible external bend of the shaft and rotation of the distal end of tibia, which limit the dorsiflexion of ankle joints, were induced following chronic gravitational unloading during developing period. It is also suggested that such phenomena are caused by the abnormal mechanical forces imposed by muscle utilization with altered patterns. The activity of ankle dorsiflexor was increased and that of plantarflexor was inhibited during unloading.


Subject(s)
Bone and Bones/anatomy & histology , Hindlimb Suspension/adverse effects , Hindlimb Suspension/physiology , Hindlimb/anatomy & histology , Hindlimb/physiology , Animals , Body Weight/physiology , Bone Development , Bone and Bones/physiology , Electromyography , Fibula/anatomy & histology , Fibula/growth & development , Hindlimb/growth & development , Joints/anatomy & histology , Locomotion/physiology , Muscle, Skeletal/anatomy & histology , Muscle, Skeletal/growth & development , Muscle, Skeletal/physiology , Organ Size/physiology , Rats , Rats, Wistar , Tibia/anatomy & histology , Tibia/growth & development
9.
Am J Physiol Cell Physiol ; 290(4): C981-9, 2006 Apr.
Article in English | MEDLINE | ID: mdl-16291821

ABSTRACT

The effects of mechanical unloading and reloading on the properties of rat soleus muscle fibers were investigated in male Wistar Hannover rats. Satellite cells in the fibers of control rats were distributed evenly throughout the fiber length. After 16 days of hindlimb unloading, the number of satellite cells in the central, but not the proximal or distal, region of the fiber was decreased. The number of satellite cells in the central region gradually increased during the 16-day period of reloading. The mean sarcomere length in the central region of the fibers was passively shortened during unloading due to the plantarflexed position at the ankle joint: sarcomere length was maintained at <2.1 microm, which is a critical length for tension development. Myonuclear number and domain size, fiber cross-sectional area, and the total number of mitotically active and quiescent satellite cells of whole muscle fibers were lower than control fibers after 16 days of unloading. These values then returned to control values after 16 days of reloading. These results suggest that satellite cells play an important role in the regulation of muscle fiber properties. The data also indicate that the satellite cell-related regulation of muscle fiber properties is dependent on the level of mechanical loading, which, in turn, is influenced by the mean sarcomere length. However, it is still unclear why the region-specific responses, which were obvious in satellite cells, were not induced in myonuclear number and fiber cross-sectional area.


Subject(s)
Muscle Fibers, Skeletal/metabolism , Muscle, Skeletal/cytology , Satellite Cells, Skeletal Muscle , Animals , Body Weight , Cell Nucleus/metabolism , Hindlimb Suspension , Male , Mitosis/physiology , Muscle Fibers, Skeletal/cytology , Muscle, Skeletal/metabolism , Random Allocation , Rats , Rats, Wistar , Satellite Cells, Skeletal Muscle/cytology , Satellite Cells, Skeletal Muscle/metabolism , Stress, Mechanical
10.
Leukemia ; 19(8): 1361-6, 2005 Aug.
Article in English | MEDLINE | ID: mdl-15902284

ABSTRACT

AML1-MTG8 generated by t(8;21) contributes to leukemic transformation, but additional events are required for full leukemogenesis. We examined whether mutations in the receptor tyrosine kinase (RTK) pathway could be the genetic events that cause acute myeloblastic leukemia (AML) harboring t(8;21). Mutations in the second tyrosine kinase domain, juxtamembrane (JM) domain and exon 8 of the C-KIT gene were observed in 10, one and three of 37 AML patients with t(8;21), respectively. Three patients showed an internal tandem duplication in the JM domain of the FLT3 gene. One patient had a mutation in the K-Ras gene at codon 12. As the occurrence of these mutations was mutually exclusive, a total of 18 (49%) patients showed mutations in the RTK pathway. These results suggest that activating mutations in the RTK pathway play a role in part as an additional event leading to the development of t(8;21) AML. The 6-year cumulative incidence of relapse in patients with RTK pathway mutations was 79.8%, compared with 13.5% in patients lacking such mutations (P=0.0029). Furthermore, the 6-year relapse-free survival in patients with mutations was 18% compared to 60% in those without mutations (P=0.0340), indicating that RTK mutations are associated with the clinical outcome in t(8;21) AML.


Subject(s)
Leukemia, Myeloid, Acute/genetics , Mutation , Receptor Protein-Tyrosine Kinases/genetics , Adolescent , Adult , Aged , Child , Child, Preschool , Chromosomes, Human, Pair 21 , Chromosomes, Human, Pair 8 , Disease-Free Survival , Female , Genes, ras , Humans , Leukemia, Myeloid, Acute/etiology , Leukemia, Myeloid, Acute/mortality , Male , Middle Aged , Proto-Oncogene Proteins/genetics , Proto-Oncogene Proteins c-kit/genetics , Receptor Protein-Tyrosine Kinases/metabolism , Recurrence , Tandem Repeat Sequences , Translocation, Genetic , Treatment Outcome , fms-Like Tyrosine Kinase 3
11.
Acta Physiol Scand ; 183(4): 389-97, 2005 Apr.
Article in English | MEDLINE | ID: mdl-15799775

ABSTRACT

AIM: The effects of cold exposure on gene and protein expression of vascular endothelial growth factor (VEGF), in heart and skeletal muscles, were studied in male adult Wistar rats. METHODS: Cold immersion was accomplished by submerging the rats in shoulder-deep water maintained at approximately 18 degrees C, either acutely (1 h) or chronically (1 h day(-1), 5 days week(-1) for 20 weeks). The expressions of VEGF mRNA and protein in heart, gastrocnemius, and soleus muscles were examined by Northern and Western blotting and competitive-polymerase chain reaction techniques. RESULTS: The expressions of VEGF mRNA and protein were markedly increased in cardiac muscle of the cold-immersed group, particularly in the 1-hour exposure group, whereas VEGF mRNA and protein in gastrocnemius were decreased significantly after an acute exposure. Although the protein level in gastrocnemius remained low in the chronically exposed group, the expression of mRNA of VEGF(165) with chronic exposure in this group returned to the control level and that of VEGF(206) was 15% greater than that in controls. The expression of mRNA for VEGF(165) in soleus was also lowered by acute cold exposure, although that for VEGF(206) was stable. However, VEGF protein was increased by 50%. After 20 weeks, all of these parameters were increased over the levels found in the controls. CONCLUSION: These results suggest that the VEGF gene may be a major regulatory factor in cardiac and skeletal muscle adaptation to the cold environment stimulating angiogenesis and thermogenesis.


Subject(s)
Cold Temperature , Heart/physiopathology , Immersion/physiopathology , Muscle, Skeletal/physiopathology , RNA, Messenger/genetics , Vascular Endothelial Growth Factor A/analysis , Actins/analysis , Animals , Gene Expression Regulation/genetics , Male , Muscle Proteins/analysis , Muscle Proteins/genetics , Myocardium/chemistry , Rats , Rats, Wistar , Vascular Endothelial Growth Factor A/genetics , Water
12.
Leukemia ; 19(5): 829-34, 2005 May.
Article in English | MEDLINE | ID: mdl-15744352

ABSTRACT

Adult T-cell leukemia/lymphoma (ATLL) is a distinct peripheral T-cell neoplasm that is highly resistant to chemotherapy. Several groups, including ours, have reported encouraging results of allogeneic hematopoietic stem cell transplantation (allo-HSCT) for patients with ATLL. To confirm our previous report and to establish the basis for a phase II clinical study, we analyzed 40 allo-HSCT for acute and lymphoma types of ATLL in seven institutions in Japan between 1997 and 2002. All evaluable cases entered complete remission (CR) after allo-HSCT and the median survival time was 9.6 months for all patients. The estimated 3-year overall and relapse-free survival, and disease relapse were 45.3, 33.8 and 39.3%, respectively. Among 10 cases with ATLL relapse, five cases achieved CR again: three by the reduction or cessation of immunosuppressive agents, which suggested a graft-versus-ATLL (GvATLL) effect. However, univariate or multivariate analysis did not show any benefit of graft-versus-host disease (GVHD) on the prevention of relapse. These results suggested that allo-HSCT was effective for some patients with aggressive ATLL, and that the GvATLL effect could be achieved even without GVHD. A new phase II trial to test the efficacy of allo-HSCT for ATLL is warranted.


Subject(s)
Hematopoietic Stem Cell Transplantation/adverse effects , Leukemia-Lymphoma, Adult T-Cell/therapy , Adult , Analysis of Variance , Female , Graft vs Host Disease/etiology , Graft vs Host Disease/therapy , Humans , Japan/epidemiology , Leukemia-Lymphoma, Adult T-Cell/mortality , Male , Middle Aged , Reproducibility of Results , Retrospective Studies , Survival Analysis , Time Factors , Transplantation, Homologous
13.
Jpn J Physiol ; 54(3): 229-42, 2004 Jun.
Article in English | MEDLINE | ID: mdl-15541201

ABSTRACT

Effects of 9-week hindlimb suspension and 8-week recovery on air-righting reaction in response to drop from a supine position were studied in adult rats. The righting time in rats at the end of suspension (approximately 220 ms) was longer than the age-matched controls (approximately 120 ms, p <0.05). The unloading-related change in righting time was accompanied by lowered activities of electromyogram (EMG) and altered recruitment of both neck and back muscles at a specific stage of drop. After 8 weeks of reambulation, righting time recovered toward the control level (approximately 153 ms, p <0.05), but the EMG activity of back muscle was still less than controls. In contrast, the EMG of neck muscle during fall was even increased. The differences in the characteristics of the muscle fibers between two groups were minor. It is suggested that inhibition of recruitment, rather than the changes in the fiber characteristics, of neck and back muscles is one of the major causes of the slow air-righting.


Subject(s)
Back/physiology , Hindlimb Suspension/methods , Movement/physiology , Muscle Contraction/physiology , Muscle Fibers, Skeletal/physiology , Muscle, Skeletal/physiology , Recruitment, Neurophysiological/physiology , Adaptation, Physiological/physiology , Animals , Electromyography , Male , Neck Muscles/physiology , Postural Balance/physiology , Posture/physiology , Rats , Rats, Wistar , Reflex, Vestibulo-Ocular/physiology
14.
Am J Physiol Regul Integr Comp Physiol ; 287(1): R76-86, 2004 Jul.
Article in English | MEDLINE | ID: mdl-15031139

ABSTRACT

Responses of electromyogram (EMG) in soleus muscle and both afferent and efferent neurograms at the fifth lumbar (L(5)) segmental level of spinal cord were investigated during acute and chronic unloading induced by hindlimb suspension and/or tenotomy in adult rats. The soleus EMG and afferent neurogram decreased 88 and 37%, respectively, relative to those at quadrupedal posture on the floor after acute hindlimb suspension that causes passive shortening of soleus due to ankle plantarflexion. However, the afferent neurogram (P < 0.05) and soleus EMG (P > 0.05) recorded on the floor increased after tenotomy of synergists. Furthermore, the afferent input was inhibited when the soleus EMG disappeared after tenotomy of soleus. The afferent neurogram and EMG of the soleus showed correlated responses to a variety of treatments, suggesting that the afferent neurogram recorded at the L(5) segmental level reflects the neural input associated with the activity level of the soleus predominantly. The level of efferent neurogram decreased after acute hindlimb suspension but was not influenced significantly by tenotomy of synergists and/or soleus itself. The EMG and afferent neurograms remained low up to the 4th day but recovered to the preexperimental levels within 14 days, due to reorganization of sarcomere number and length, as well as the shortening of muscle fiber length and recovery of tension development. It is suggested that the levels of EMG and afferent neurogram associated with antigravity muscle are closely related to the tension development of the muscle.


Subject(s)
Hindlimb Suspension/physiology , Muscle, Skeletal/physiology , Peripheral Nerves/physiology , Animals , Body Weight/physiology , Eating/physiology , Electrodes, Implanted , Electromyography , Male , Motor Neurons/physiology , Muscle Contraction/physiology , Muscle Fibers, Skeletal/physiology , Muscle Fibers, Skeletal/ultrastructure , Muscle, Skeletal/innervation , Rats , Rats, Wistar , Sarcomeres/physiology , Sarcomeres/ultrastructure
15.
Jpn J Physiol ; 54(4): 331-7, 2004 Aug.
Article in English | MEDLINE | ID: mdl-15631688

ABSTRACT

The effects of 20 weeks of intermittent cold-water-immersion on myosin heavy chain (MHC) expression,cross-sectional area (CSA), myonuclear number, and myonuclear domain size in isolated single fiber of soleus and extensor digitorum longus (EDL) muscles were studied in male Wistar rats. Cold exposure was accomplished by submerging the rats in shoulder-deep water, maintained at approximately 18 degrees C, for 1 hour/day, 5 days/week and for 20 weeks. Cold exposure resulted in a significant inhibition of body and soleus muscle weight gain. The percent type IIa MHC fibers of EDL muscle was increased, whereas that of type IIa + b MHC fibers was less in cold-exposed group than controls (p < 0.05). The mean CSA and myonuclear number in type I MHC fibers of soleus muscle in cold-exposed group were significantly less than controls. Myonuclear domain in type IIa fibers of EDL in the cold-exposed group was greater than controls (p < 0.05). It is suggested that prolonged cold exposure causes the fiber-type-specific adaptation in rat hindlimb muscles. It is further indicated that cold-exposure-related modulation of myonuclear number was closely related to reduction of fiber CSA, not the shift of fiber phenotype.


Subject(s)
Cold Temperature , Muscle Fibers, Skeletal/physiology , Muscle Fibers, Skeletal/ultrastructure , Muscle, Skeletal/physiology , Myosin Heavy Chains/biosynthesis , Animals , Body Weight , Hindlimb/physiology , Male , Muscle, Skeletal/growth & development , Phenotype , Rats , Rats, Wistar , Weight Gain
16.
Kyobu Geka ; 56(6): 497-500, 2003 Jun.
Article in Japanese | MEDLINE | ID: mdl-12795157

ABSTRACT

The ruptured aortic arch aneurysm with cardiac tamponade is rare and has severely high mortality. We report a case of ruptured aortic arch aneurysm with cardiac tamponade. A 66-year-old man who had syncope attack was transferred to city hospital. Brain computed tomography (CT) showed no significant lesion and he admitted to our hospital for suspecting of aortic dissection. Chest CT showed ruptured aortic arch aneurysm and pericardial effusion. Emergent operation was done on the same day. It was found that the hematoma beneath the tunica adventitia existed at the distal arch and extended to the ascending aorta. Cardiac tamponade was caused by rupture of subadventitial hematoma in pericardial space. Aortic arch replacement was performed using selective cerebral perfusion under deep hypothermia. Postoperatively, he had no cerebral complication and was discharged uneventfully.


Subject(s)
Aortic Aneurysm, Thoracic/complications , Aortic Rupture/complications , Cardiac Tamponade/etiology , Aged , Aorta, Thoracic/surgery , Aortic Aneurysm, Thoracic/surgery , Aortic Rupture/surgery , Blood Vessel Prosthesis Implantation , Cardiac Tamponade/surgery , Humans , Male
17.
J Musculoskelet Neuronal Interact ; 3(2): 162-9, 2003 Jun.
Article in English | MEDLINE | ID: mdl-15758357

ABSTRACT

The densities and cross-sectional areas (CSAs) of the femur in 40- and 60-week-old senescence-accelerated mice prone 6 (SAMP6) were determined using peripheral quantitative computed tomography (pQCT) and compared with those in age-matched control mice (ICR). In addition, the effects of 20 weeks of voluntary running exercise with increasing loads on femur density and CSA were examined in SAMP6. There were no differences in the cortical and trabecular densities or CSAs between the 40- and 60-week-old ICR. The cortical and trabecular densities of the 60-week-old control SAMP6 were lower than those of the 40-week-old control SAMP6. There was no difference in the cortical CSA between the 40- and 60-week-old control SAMP6, while the trabecular CSA of the 60-week-old control SAMP6 was higher than that of the 40-week-old control SAMP6. It was concluded that an age-related decline in femur cortical and trabecular densities occurs at an earlier age in control SAMP6, indicating that SAMP6 show accelerated progression of age-associated osteoporosis. There were no differences in the cortical density between the 40-week-old control and 60-week-old exercised SAMP6. These data indicate that running exercise with increasing loads prevents age-associated osteoporosis in this senescence-accelerated mouse strain.

18.
Am J Hematol ; 71(4): 248-55, 2002 Dec.
Article in English | MEDLINE | ID: mdl-12447952

ABSTRACT

1998, a consensus meeting was held in Miyazaki, Japan, to develop an approach to management of febrile neutropenia (FN). The K-HOT study group decided to examine whether this proposal was applicable to clinical practice in a multicenter study. Patients who developed fever with neutrophil counts <1,000/microL were randomized to receive either a single antibiotic, cefepime or one of the carbapenems, or a combination of cefepime and an aminoglycoside. Patients who became afebrile within the first 3 days were continued on the same treatment. Patients who remained febrile were switched to a combination regimen if they were randomized to receive a single agent, and patients on combination medication were changed from cefepime to another cephalosporin. A total of 165 patients were entered into the trial. One hundred fifty-three patients were evaluable for response. The average age was 52 years, and 70% of the patients had acute leukemia. Severe neutropenia, defined as <100/microL at the time of FN, was seen in 62% of the patients on entry and during the course of treatment 71% of patients experienced neutrophil counts of <100/microL. Microbiologically documented infection was seen in 6.5% for monotherapy, and 10.5% for a combination treatment, and fever of unknown origin occurred in 75.3% and 59.2% of the patients in each regimen, respectively. Excellent to good response was seen in two-thirds of the patients in all treatment groups. Adverse events were minimal, and three early deaths were observed at days 9, 16, and 16 among patients treated with a single antibiotic and three in the combination regimen group at days 14, 15, and 20. These results indicate that cefepime or a carbapenem alone is as effective as a combination of cefepime and an aminoglycoside for treating FN.


Subject(s)
Anti-Bacterial Agents/therapeutic use , Carbapenems/therapeutic use , Cephalosporins/therapeutic use , Drug Therapy, Combination/therapeutic use , Fever/etiology , Neutropenia/drug therapy , Adult , Algorithms , Aminoglycosides , Carbapenems/administration & dosage , Cefepime , Cephalosporins/administration & dosage , Drug Administration Schedule , Female , Humans , Leukemia/physiopathology , Lymphoma/physiopathology , Male , Neutropenia/etiology
19.
Neuroscience ; 114(4): 1133-8, 2002.
Article in English | MEDLINE | ID: mdl-12379265

ABSTRACT

Responses of electromyogram (EMG) of soleus, lateral portion of gastrocnemius (LG) and tibialis anterior (TA), and both afferent and efferent neurograms at the L(5) segmental level of the spinal cord, to altered gravity levels created by the parabolic flight of a jet airplane were investigated in adult rats. The EMG activity in antigravity soleus muscle gradually increased when the gravity was elevated from 1-G to 1.5-G (+23%) and 2-G (+67%) during the ascending phase of parabolic flight. The activity decreased approximately 72% from the 1-G level immediately when the rat was exposed to microgravity. The EMG level was maintained low during the 20-s microgravity, but it was restored immediately once the gravity level was increased to 1.5-G and then 1-G during the descending and recovery phase. The EMG level of LG also increased gradually when the gravity level was elevated and the level then decreased when the rat was exposed to microgravity (P>0.05). However, the activity level during the 20-s microgravity was identical to that obtained at 1-G. The EMG level of TA even increased insignificantly in response to the exposure to microgravity. The responses of afferent neurogram were similar to those of soleus EMG, even though the magnitude of the reduction of integrated neurogram level in response to microgravity exposure was small (approximately 26% vs. 1-G level) relative to that of soleus EMG. The level of efferent neurogram was also decreased, but only approximately 9% vs. 1-G level, during the 20-s microgravity. The data in the current study suggest that the afferent input is closely associated with the gravity-dependent muscular activity.


Subject(s)
Muscle, Skeletal/innervation , Muscle, Skeletal/physiology , Neurons, Afferent/physiology , Weightlessness , Aircraft , Animals , Electromyography , Joints/physiology , Male , Neurons, Efferent/physiology , Rats , Rats, Wistar
20.
Ann Oncol ; 13(9): 1347-55, 2002 Sep.
Article in English | MEDLINE | ID: mdl-12196359

ABSTRACT

BACKGROUND: CHOP (cyclophosphamide, doxorubicin, vincristine and prednisone) is accepted as the best available standard treatment for first-line chemotherapy in aggressive non-Hodgkin's lymphoma (NHL). However, the therapeutic efficacy of CHOP remains unsatisfactory, particularly in high-intermediate risk and high risk patients, and a new strategy is warranted in this patient population. The aim of the present study was to explore a suitable therapeutic-intensified regimen for the treatment of aggressive NHL. PATIENTS AND METHODS: Between May 1995 and July 1998, a total of 70 patients with high-intermediate risk or high risk aggressive NHL, according to the International Prognostic Index, were enrolled and randomly assigned to receive either eight cycles of standard CHOP (cyclophosphamide 750 mg/m(2), doxorubicin 50 mg/m(2), vincristine 1.4 mg/m(2) and prednisolone 100 mg for 5 days) every 2 weeks, or six cycles of dose-escalated CHOP (cyclophosphamide 1500 mg/m(2), doxorubicin 70 mg/m(2), vincristine 1.4 mg/m(2) and prednisolone 100 mg for 5 days) every 3 weeks. Lenograstim (glycosylated rHuG-CSF), at a dose of 2 micro g/kg/day s.c., was administered daily from day 3 until day 13 with biweekly CHOP and until day 20 with the dose-escalated CHOP. The primary endpoint was complete response rate. RESULTS: The complete response rate was 60% [21 of 35; 95% confidence interval (CI) 42% to 76%] with biweekly CHOP and 51% (18 of 35; 95% CI 34% to 69%) with dose-escalated CHOP. The major toxicity was grade 4 neutropenia and was more frequent in the dose-escalated CHOP arm (86%) than in the biweekly CHOP arm (50%). Grade 4 thrombocytopenia was also more frequent in the dose-escalated CHOP arm (20%) than the biweekly CHOP arm (3%). Non-hematological toxicities were acceptable in both arms. One treatment-related death (due to cardiac arrhythmia) was observed in a dose-escalated CHOP patient. Progression-free survival at 3 years was 43% (95% CI 27% to 59%) in the biweekly CHOP arm and 31% (95% CI 16% to 47%) in the dose-escalated CHOP arm. Although seven patients were deemed ineligible by central review of the pathological diagnosis, the results for both eligible and all enrolled patients were similar. CONCLUSIONS: Similar complete response rates and progression-free survival rates, but lower toxicity, indicated that biweekly CHOP was superior to dose-escalated CHOP in the treatment of aggressive NHL. Based on these results, the Lymphoma Study Group of the Japan Clinical Oncology Group is conducting a randomized phase III study comparing biweekly CHOP with standard CHOP in newly diagnosed patients with advanced-stage aggressive NHL.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/administration & dosage , Cyclophosphamide/administration & dosage , Doxorubicin/administration & dosage , Granulocyte Colony-Stimulating Factor/administration & dosage , Lymphoma, Non-Hodgkin/drug therapy , Maximum Tolerated Dose , Neutropenia/prevention & control , Prednisolone/administration & dosage , Recombinant Proteins/administration & dosage , Vincristine/administration & dosage , Adult , Aged , Antineoplastic Combined Chemotherapy Protocols/adverse effects , Confidence Intervals , Cyclophosphamide/adverse effects , Disease-Free Survival , Dose-Response Relationship, Drug , Doxorubicin/adverse effects , Drug Administration Schedule , Female , Follow-Up Studies , Humans , Infusions, Intravenous , Japan , Lenograstim , Lymphoma, Non-Hodgkin/diagnosis , Lymphoma, Non-Hodgkin/mortality , Male , Middle Aged , Prednisolone/adverse effects , Probability , Risk Assessment , Survival Analysis , Treatment Outcome , Vincristine/adverse effects
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