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K Kaneda

Publications and source records attributed to K Kaneda.

At least 19 recordsLinked to original sources
PubMed2006

DNA methylation: its contribution to systemic lupus erythematosus.

Recent studies on epigenetics, including the methylation of DNA and the enzymes regulating methylation, seem likely to contribute to understanding the pathogenesis of autoimmune diseases such as systemic lupus erythematosus (SLE). In fact, the relationship between DNA methylation and SLE has long been the subject of investigation. To obtain a deeper understanding of the role of DNA methylation in the onset of SLE, we reviewed the findings reported in the literature and our own data about DNA methylation and SLE. Various studies have indicated the possible importance of DNA methylation, especially hypomethylation, in the aetiology of SLE. Epigenetic studies may provide clues for elucidating the pathogenesis of SLE and for developing new strategies to treat this disease.

Animals↗
PubMed2006

Secondary medulla oblongata involvement following middle cervical spinal cord injury associated with latent traumatic instability in a patient with ossification of the posterior longitudinal ligament.

STUDY DESIGN: A case report. OBJECTIVES: To report a rare case of extension of edema and hemorrhage from initial C4-5 spinal injury to the medulla oblongata. SETTING: Center for Spinal Disorders and Injuries, Bibai Rosai Hospital, Japan. METHODS: A 68-year-old man with ossification of the posterior longitudinal ligament (OPLL) had sustained tetraplegia after tumbling over a stone. Initially, the patient was diagnosed with an acute C4-5 spinal cord injury without radiological abnormalities and was treated conservatively. At 7 h after the injury, the patient had an ascending neurological deficit, which required respiratory assistance. Magnetic resonance imaging revealed a marked swelling of the spinal cord above C4-5 extending to the medulla oblongata. RESULTS: Retrospective radiological assessment revealed that the spine was unstable at the injury level because of discontinuities in both anterior and posterior longitudinal ligaments. There was also signal intensity change within the retropharyngeal space at the C4-5 intervertebral disc. This injured segment was highly vulnerable to post-injury dynamic stenosis and easily sustained secondary neural damage. CONCLUSIONS: This case report emphasizes a careful radiological assessment of latent structural instability in patients with OPLL in order to detect and prevent deteriorative change in the spinal cord.

Aged↗
PubMed2005

Seroepidemiology of Borrelia burgdorferi sensu lato and Anaplasma phagocytophilum in wild mice captured in northern Turkey.

An expedition across the Asian part of the Black Sea coast and national parks of Northern Turkey was organized in the summer of 2001 to investigate the presence of Borrelia burgdorferi sensu lato (s.l.), Lyme borreliosis agent, and Anaplasma phagocytophilum, human granulocytic ehrlichiosis, agent, in wild mice. A total of 65 Apodemus flavicollis, Apodemus sylvaticus, Microtus epiroticus, Crocidura suaveolens and Mus macedonicus, were captured. Two out of 22 Apodemus sylvaticus specimens were seropositive for B. afzelii by enzyme-linked immunosorbent assay as confirmed by Western blotting, however cultures of skin and bladder samples from all small mammals in Barbour-Stoenner-Kelly's medium-II remained negative for B. burgdorferi s.l. All sera tested were negative for Anaplasma phagocytophilum by indirect immunofluorescent assay. The prevalence of B. burgdorferi s.l. and Anaplasma phagocytophilum is low in wild mice of the Asian part of Northern Turkey.

Anaplasma phagocytophilum↗
PubMed2005

Down-regulation of metabotropic glutamate receptor 1alpha in globus pallidus and substantia nigra of parkinsonian monkeys.

Enhanced glutamatergic neurotransmission via the subthalamopallidal or subthalamonigral projection seems crucial for developing parkinsonian motor signs. In the present study, the possible changes in the expression of metabotropic glutamate receptors (mGluRs) were examined in the basal ganglia of a primate model for Parkinson's disease. When the patterns of immunohistochemical localization of mGluRs in monkeys administered systemically with 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) were analysed in comparison with normal controls, we found that expression of mGluR1alpha, but not of other subtypes, was significantly reduced in the internal and external segments of the globus pallidus and the substantia nigra pars reticulata. To elucidate the functional role of mGluR1 in the control of pallidal neuron activity, extracellular unit recordings combined with intrapallidal microinjections of mGluR1-related agents were then performed in normal and parkinsonian monkeys. In normal awake conditions, the spontaneous firing rates of neurons in the pallidal complex were increased by DHPG, a selective agonist of group I mGluRs, whereas they were decreased by AIDA, a selective antagonist of group I mGluRs, or LY367385, a selective antagonist of mGluR1. These electrophysiological data strongly indicate that the excitatory mechanism of pallidal neurons by glutamate is mediated at least partly through mGluR1. The effects of the mGluR1-related agents on neuronal firing in the internal pallidal segment became rather obscure after MPTP treatment. Our results suggest that the specific down-regulation of pallidal and nigral mGluR1alpha in the parkinsonian state may exert a compensatory action to reverse the overactivity of the subthalamic nucleus-derived glutamatergic input that is generated in the disease.

1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine↗
PubMed2004

Role of ionotropic glutamatergic and GABAergic inputs on the firing activity of neurons in the external pallidum in awake monkeys.

The neurons in the external segment of the pallidum (GPe) in awake animals maintain a high level of firing activity. The level and pattern of the activity change with the development of basal ganglia disorders including parkinsonism and hemiballism. The GPe projects to most of the nuclei in the basal ganglia. Thus exploring the mechanisms controlling the firing activity is essential for understanding basal ganglia function in normal and pathological conditions. To explore the role of ionotropic glutamatergic and GABAergic inputs to the GPe, unit recordings combined with local injections of receptor antagonists were performed in awake monkeys. Observations on the effects of local application of the alpha-amino-3-hydroxy-5-methylisoxazole-4-propionic acid (AMPA)/kainate antagonist 1,2,3,4-tetrahydro-6-nitro-2, 3-dioxo-benzo[f]quinoxaline-7-sulfonamide, the N-methyl-D-aspartic acid (NMDA) antagonist 3-(2-carboxypiperazin-4-yl)-propyl-1-phosphonic acid, and the GABAA antagonist gabazine as well as the effects of muscimol blockade of the subthalamic nucleus on the spontaneous firing rate, firing patterns, and cortical stimulation induced responses in the GPe suggested the following: sustained glutamatergic and GABAergic inputs control the level of the spontaneous firing of GPe neurons; both AMPA/kainate and NMDA receptors are activated by glutamatergic inputs; some GPe neurons receive glutamatergic inputs originating from areas other than the subthalamic nucleus; no GPe neurons became silent after a combined application of glutamate and GABA antagonists, suggesting that GPe neurons have intrinsic properties or nonionotropic glutamatergic tonic inputs that sustain a fast oscillatory firing or a combination of a fast and a slow oscillatory firing in GPe neurons.

Animals↗
PubMed2003

Plasma stromal cell-derived factor-1 during granulocyte colony-stimulating factor-induced peripheral blood stem cell mobilization.

In this report, we examined plasma stromal cell-derived factor-1 levels in normal healthy donors for allogeneic peripheral blood stem cell transplantation (PBSCT) and in patients for autologous PBSCT using an enzyme-linked immunosorbent assay. The average level of plasma stromal cell-derived factor-1 was 2197 pg/ml before granulocyte colony-stimulating factor administration and 1899 pg/ml on day 4, demonstrating a significant decrease in the peripheral blood of healthy donors (P=0.0003). In patients for autologous PBSCT, a significant decrease of plasma stromal cell-derived factor-1 in the peripheral blood was also observed (P=0.0464). However, the physiologic gradient of stromal cell-derived factor-1 between peripheral blood and bone marrow was never inverted in normal healthy donors or in autologous PBSCT patients. Our results suggest that stromal cell-derived factor-1 may not be involved in the granulocyte colony-stimulating factor-induced release of CD34(+) cells to the peripheral blood. Further studies of a possible additive effect of granulocyte colony-stimulating factor and stromal cell-derived factor-1 are warranted.

Adult↗
PubMed2003

Induction of cutaneous delayed hypersensitivity reactions in mice sensitized with intragastrically administered hapten: activation of Langerhans cells in the sensitization and elicitation phases.

BACKGROUND: As seen in atopic dermatitis, allergic diseases often produce lesions both in the gastrointestinal tract and the skin, suggesting the involvement of an immunological relationship between the two organs in the pathogenesis. OBJECTIVES: To study the role of gastric and epidermal Langerhans cells (LCs) in the sensitization and elicitation phases, respectively, of cutaneous delayed-type hypersensitivity (DTH) reactions to intragastrically administered hapten. METHODS: BALB/c mice, which were subjected to intragastric administration of trinitrochlorobenzene 5 days previously, received an elicitative challenge of the same hapten to the ear skin. Sections of the ear were immunostained for CD4 and CD8. Epidermal sheets of the ear and epithelial sheets of the forestomach were immunostained for I-A and observed under a confocal laser scanning microscope. RESULTS: Cutaneous DTH reactions were induced in mice, as demonstrated by an increase in ear thickness and a prominent infiltration of CD4+ and CD8+ lymphocytes at 24-36 h after the elicitative challenge. In the elicitation phase, epidermal LCs showed a significant increase in size, indicating in vivo activation, at 24 h. In the sensitization phase, gastric LCs increased in size at 2 h, became round at 6 h, and decreased in number at 24 h, possibly representing the sequential events of LC activation and migration from the epithelium. CONCLUSIONS: The present study demonstrated that gastric LCs and epidermal LCs were activated in vivo in the sensitization and elicitation phases, respectively, of cutaneous DTH reactions in orally sensitized mice.

Animals↗
PubMed2003

Monitoring of neuromuscular block after administration of vecuronium in patients with diabetes mellitus.

BACKGROUND: We studied the supramaximal current for ulnar nerve stimulation during electromyographic monitoring of onset and recovery of neuromuscular block using a neuromuscular transmission module (M-NMT Module, Datex-Ohmeda) in patients with Type 2 diabetes undergoing anaesthesia with nitrous oxide, oxygen, isoflurane and fentanyl. METHODS: Thirty-six diabetic patients were randomly assigned to a post-tetanic count (PTC) group (n=17) or train-of-four (TOF) group (n=19). In addition, 30 non-diabetic patients were divided into control PTC (n=15) and TOF groups (n=15). RESULTS: In the diabetic patients (diabetes PTC and diabetes TOF groups), the mean supramaximal stimulating current was significantly higher than in the non-diabetic patients (control PTC and TOF groups) (50.5 (SD 14.1) vs 33.4 (6.1) mA, P<0.01). Onset of neuromuscular block (time to disappearance of T1) after vecuronium 0.1 mg kg(-1) in the diabetic patients did not differ significantly from that in the non-diabetic patients (276 (77) vs 244 (44) s, P=0.055). Time to return of PTC1 did not differ significantly between the diabetes and control PTC groups (21.0 (12.1) vs 15.7 (5.0) min, P=0.126). Times to return of T1 and T4 in the diabetes TOF group were significantly longer than in the control TOF group (T1: 37.5 (15.2) vs 25.7 (7.6) min, P=0.01; T4: 61.4 (23.7) vs 43.5 (11.4) min, P=0.01). During recovery, PTC and T4/T1 in the diabetes PTC and TOF groups were similar to those in the control PTC and TOF groups, respectively. T1/T0 in the diabetes TOF group was significantly less than in the control TOF group, 80-120 min after vecuronium (P<0.05). CONCLUSIONS: In diabetic patients, supramaximal current is higher than in non-diabetic patients. After vecuronium, onset of neuromuscular block and recovery of PTC or T4/T1 are not altered, but time to return of T1 or T4, and recovery of T1/T0 are delayed in diabetic patients.

Adult↗
PubMed2003

[Aortic dissection presenting with neurologic sign; report of a case].

A 59-year-old man was admitted to our hospital for neurological deficit and left hemiplegia, presenting remission in the short time. Computed tomography(CT) of the brain was normal. CT of the chest showed a thoracoabdominal aortic dissection from the ascending aorta to the bilateral femoral artery, that involved all cervical arteries. The intimal flap separated the false and true lumens and there was flow in both lumens. That phenomenon can be due to the extension of the dissection along the aorta, occluding the origin of the cervical arteries and the change of the flow by the intimal flap. He was amputated his left leg below knee on the 1 postoperative day (POD), but discharged at 70 POD without neurologic complications.

Aortic Dissection↗
PubMed2002

Bilateral adrenal hemorrhage in essential thrombocythemia.

A 67-year-old woman with previously untreated essential thrombocythemia developed bilateral adrenal hemorrhage. She had no known vascular risk factors including smoking, diabetes mellitus, hypertension, and hypercholesterolemia. Her platelet count was 921 x 10(9)/l. She received preemptive steroid therapy to prevent the occurrence of adrenal crisis, but 5 weeks later the replacement therapy was discontinued because the patient fully recovered with a normal adrenocorticotropic hormone stimulation test. Thereafter, she remained well for more than 4 years with a platelet count ranging from 600 to 800 x 10(9)/l. Although adrenal hemorrhage is very rare, it can occur as a hemorrhagic complication of essential thrombocythemia.

Adrenal Gland Diseases↗
PubMed2002

The effect of ulinastatin pre-treatment on vecuronium-induced neuromuscular block in patients with hepatic cirrhosis.

The aim of this study was to investigate the effect of ulinastatin, a protease inhibitor, on the neuromuscular block produced by vecuronium in patients with hepatic cirrhosis. Thirty adult patients with hepatic cirrhosis were randomly allocated to receive ulinastatin (cirrhosis/ulinastatin group, n = 15) or saline (cirrhosis/saline group, n = 15). Fifteen healthy adult patients without hepatic cirrhosis comprised a control group. Patients were given a standardised anaesthetic that included nitrous oxide and isoflurane in oxygen, and fentanyl. A bolus dose of ulinastatin 5000 unit x kg(-1) was given to members of the cirrhosis/ulinastatin group. The same volume of normal saline was given to the other two groups. Two minutes later, vecuronium 0.1 mg x kg(-1) was given. The onset of neuromuscular block was significantly slower in the cirrhosis/ulinastatin group than in the cirrhosis/saline and control groups (p < 0.05). Spontaneous recovery of neuromuscular function was significantly quicker in the cirrhosis/ulinastatin and control groups than in the cirrhosis/saline group (p < 0.05). The time course of recovery in the cirrhosis/ulinastatin and control groups was similar. We conclude that in cirrhotic patients, ulinastatin delays the onset of neuromuscular block produced by vecuronium. After pretreatment with ulinastatin, the speed of recovery from neuromuscular block in patients with cirrhosis becomes similar to that seen in healthy patients.

Aged↗
PubMed2002

Skeletal muscle regeneration associated with the stroma reaction during tumor invasion in the rat tongue.

This study was aimed to demonstrate the regeneration of skeletal muscle fibers in the stroma reaction during tumor invasion, using the rat model of tongue carcinoma. By oral administration of 4-nitroquinoline N-oxide, squamous cell carcinoma (SCC) appeared in the epithelium, and deeply invaded the muscular layer, inducing the stroma reaction around the tumor. Regenerating muscle fibers, characterized by the immature profiles of sparse myofibrils, centrally disposed multi-nuclei, and abundant mitochondria, were extended from the surrounding normal muscles into the stroma. By immunohistochemistry, some of them expressed BF-45, a marker for an early stage of myodifferentiation, similar to the regenerating muscle fibers in the bupivacaine hydrochloride-induced injury. They were closely associated with the stromal components such as ED-1-positive macrophages, alpha-smooth muscle actin-positive myofibroblasts, and factor VIII-related antigen-positive vascular endothelial cells, suggesting the roles of their interactions in muscle regeneration. Immature muscle fibers were usually devoid of acetylcholinesterase-positive endplates on them, but some were reinnervated by the terminal axons. The present results indicate that skeletal muscle regeneration is induced in association with the stroma reaction during SCC invasion in the tongue.

4-Nitroquinoline-1-oxide↗
PubMed2001

Biomechanical evaluation of anterior spinal instrumentation systems for scoliosis: in vitro fatigue simulation.

STUDY DESIGN: A biomechanical study was designed to assess the bone-screw interface fixation strength among five anterior spinal instrumentation systems for scoliosis before and after a fatigue simulation. OBJECTIVES: The objectives of the current study were twofold: 1) evaluate the static (initial) strength at the bone-screw interface and 2) evaluate dynamic (post fatigue) strength of the bone-screw interface after a fatigue simulation to investigate a possible mechanism for postoperative loss of correction. SUMMARY OF BACKGROUND DATA: Although the recent advancement of anterior instrumentation for scoliosis has permitted shorter fusion segments and improved surgical correction, the loss of correction over the instrumented segments still has been reported in one-rod systems. Little is known about the mechanism for loss of correction. METHODS: Twenty-five fresh-frozen calf spines (T6-L6) were used. A total of five instrumentation systems included the following: Anterior ISOLA (ISOLA), Bad Wildungen Metz (BWM), Texas Scottish Rite Hospital system (TSRH), Cotrel-Dubousset Hoph (CDH), and Kaneda Anterior Scoliosis System (KASS). Screw pullout and rotational tests in the sagittal plane using a single vertebra were performed to investigate bone-screw interface fixation strength before and after a fatigue simulation. To simulate cyclic loading that the spine could undergo in vivo, a fatigue simulation using compressive-flexion loading up to 24,000 cycles was carried out. RESULTS: Mean maximum tensile pullout force decreased in the following order: KASS > CDH > BWM > TSRH > ISOLA (F = 29.91, P < 0.0001). KASS blunt tip screw was 26% stronger in pullout force than KASS sharp tip screw (P < 0.05). The one-rod system demonstrated a positive correlation between pullout force and both bone mineral density and screw insertional torque. For fatigue analysis the rotational strength at the most cephalad and caudal segments significantly decreased after a fatigue simulation in the one-rod system (P < 0.05). The two-rod system showed no significant decrease after a fatigue simulation. CONCLUSIONS: Simulating the cyclic loading to the construct, screw loosening at the bone-screw interface was produced in the one-rod system. This screw loosening may elucidate one mechanism for loss of correction in the one-rod system. The two-rod system may have the potential to minimize the risk of loss of correction.

Analysis of Variance↗
PubMed2001

Therapy-related myelodysplastic syndrome/acute myeloid leukemia M2 and translocation (8;21).

An 80-year-old woman developed therapy-related myelodysplastic syndrome with translocation (8;21), which was successfully treated with an acute myeloid leukemia oriented chemotherapy. Five years before admission she had received cyclophosphamide, epirubicin, and carboplatin for endometrial cancer. The leukemia cell morphology alerted us to the possibility of the presence of t(8;21) before cytogenetic results were obtained, and AML1/ETO fusion transcript was detected by reverse transcription polymerase chain reaction. She achieved complete remission after one course of idarubicin and cytosine arabinoside. She has remained in complete remission for 6 months. Our experience suggests that recognition of typical morphological features for de novo M2 acute myeloid leukemia with t(8;21) would be important in diagnosis of therapy related myelodysplastic syndrome/acute myeloid leukemia with this translocation, which could respond to an intensive chemotherapy.

Aged↗
PubMed2001

Biomechanical and morphologic evaluation of a three-dimensional fabric sheep artificial intervertebral disc: in vitro and in vivo analysis.

STUDY DESIGN: We have developed a new artificial intervertebral disc consisting of triaxial three-dimensional fabric for the sheep lumbar spine. To clarify the characteristics of the new implant, a series of biomechanical tests and morphologic evaluations were conducted. OBJECTIVES: To investigate the static, viscoelastic, and fatigue properties of the three-dimensional fabric disc in comparison with natural sheep disc and to evaluate their biomechanical and morphologic alteration in vivo. SUMMARY OF BACKGROUND DATA: In its human dimensions the three-dimensional fabric disc revealed mechanical properties similar to a natural human disc. METHODS: The disc-body units from sheep spine and the sheep three-dimensional fabric discs underwent tensile-compressive (200 N), torsional (5 Nm), and creep-recovery tests (30 minutes-30 minutes, 200 N). After fatigue loading (2 million, compressive 200 N) the biomechanical changes and the debris were investigated. For in vivo evaluation after placing in the sheep psoas muscles for 6 months, the surface of the three-dimensional fabric disc was evaluated using macroscopy and scanning electron microscopy, followed by previous biomechanical tests. RESULTS: The behavior of the sheep three-dimensional fabric disc was similar to that of natural sheep disc in tensile-compressive and creep-recovery tests. In torsional testing the behavior of natural sheep disc was more rigid than that of the sheep three-dimensional fabric disc. After fatigue loading there was no biomechanical change and no debris detected. Six months after surgery no morphologic deterioration was observed nor were there changes in biomechanical parameters. CONCLUSIONS: The sheep three-dimensional fabric disc exhibited biomechanical and morphologic biostability, appropriate viscoelasticity, and excellent fatigue properties. The three-dimensional fabric disc has a potential for clinical application of human intervertebral disc replacement.

Animals↗
PubMed2001

Immunopathogenesis of delayed-type hypersensitivity.

Cell-mediated immunity is defined as a beneficial host response characterized by an expanded population of specific T cells, which, in the presence of antigens, produce cytokines locally. The activation and recruitment of cells into an area of inflammation is a crucial step in the development of DTH responses. DTH is immunologically a process similar to cell-mediated immunity, involving T cells and cytokines. CD4 T helper (Th) 1 cells, differentiated from naive Th cells by IL-12 and IL-18 produced from macrophages, play a regulatory role in the expression of DTH and activation of macrophages via interferon gamma generated by Th1 and natural killer cells. Macrophages accumulate at the site of DTH and become activated through the CD4 Th1 cell-cytokine-macrophage axis. However, DTH leads to pathologic responses, such as granulomatous inflammation, calcification, caseation necrosis, and cavity formation. Granulomas usually form as a result of the persistence of a nondegradable product or as the result of DTH responses. DTH is also required for host defense against etiologic agents, such as Mycobacterium tuberculosis. The expression of cell-mediated immunity/DTH is a double-edged sword that may contribute to both clearance of the etiologic agent and tissue damage.

Antibodies↗
PubMed2001

Peribronchiolar accumulation of dendritic cells and their close association with CD4(+) T cells in the murine lung hypersensitivity.

In order to understand the interaction between dendritic cells (DCs) and helper T (Th) cells in the region exposed to antigens during pulmonary delayed-type hypersensitivity (DTH), which is considered to be mediated by Th1 cells, we immunohistochemically investigated their spatial relationship in the cellular infiltrate. At 24 hours after intratracheal instillation of hapten in sensitized mice, DCs were preferentially accumulated around the bronchioles, whereas macrophages were more abundant around the accompanying arteries. DCs often formed a cluster, in which they were interconnected with each other by projections. Serial section analysis revealed that clustered DCs made a close apposition to Th cells but much less frequently to cytotoxic T cells and B cells. Immunoelectron microscopy demonstrated that lymphocytes extravasated the capillaries in the peribronchiolar interstitium and made conjugation with DCs. In the interstitial tissue, DCs often adhered to the fibroblasts, suggesting the supportive role of the latter cells in DC migration. Eosinophils were also frequent around the arteries, representing the possible involvement of Th2 cytokines. By contrast, in a chronic type of airway inflammation induced by repeated challenges of aerosolized ovalbumin, DCs were densely and diffusely accumulated around the arteries in the same way as macrophages. The present study demonstrated a close association of DCs with Th cells around the bronchioles during pulmonary DTH, suggesting that local interaction between them in the lung may play important roles in the development of this disorder.

Animals↗