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Biomedical subjects

K Ohtsuka

Publications and source records attributed to K Ohtsuka.

At least 19 recordsLinked to original sources
PubMed2006

Prediction of gait outcome with the knee-ankle-foot orthosis with medial hip joint in patients with spinal cord injuries: a study using recursive partitioning analysis.

STUDY DESIGN: Retrospective study of the degree of gait independence achieved by persons with spinal cord injury (SCI) using knee-ankle-foot orthosis with a medial single hip joint (MSH-KAFO). OBJECTIVE: To examine the effects of the neurological level, degree of paresis, age, and inhibitory physical/other factors on the gait with a MSH-KAFO in patients with SCIs. SETTING: Three university hospitals and two rehabilitation hospitals in Japan. METHODS: The 45 patients (36 men, nine women) examined included 10 with injuries in the cervical cord between C6 and C8 (group C), 20 with injuries in the upper-middle thoracic cord between T4 and T10 (group UT), and 15 with injuries in the lower thoracic-lumbar cord between T12 and L1 (group TL). Mean age was 34.0 years (range 16-68 years). Of these patients, 13 used the Walkabout, four used the gear joint, and 28 used the Primewalk as the medial hip joint. Recursive partitioning, which predicted the final status of gait from the level, degree of paresis, age, and inhibitory factors, was performed, and a decision tree for gait was constructed. Inhibitory factors were spasticity, involuntary spasms or muscle contractions, pain, contracture, weakness of the upper extremities, and decreased motivation to perform gait exercise. The degree of gait independence was rated on the following five-point scale: outdoor independent gait (5 points), indoor independent gait (4 points), indoor supervised gait (3 points), indoor assisted gait (2 points), and gait within parallel bars (1 point). New branches were added to the decision tree for gait based on the clinical experience, thereby constructing a new decision tree. RESULTS: The coincident ratio between the value predicted on the basis of the decision tree of gait and the value actually observed was 53.3%. The coincident ratio between the value predicted on the basis of the modified decision tree of gait and the actually observed value was 68.9%. CONCLUSION: The results provide valuable information to medical teams that may assist prescription of gait orthoses.

Adolescent↗
PubMed2005

Inducers and co-inducers of molecular chaperones.

Molecular chaperones, which are mostly heat- or stress-induced proteins (HSPs), not only regulate various cellular functions such as protein folding, refolding of partially denatured proteins, protein transport across membranes, cytoskeletal organization, degradation of disabled proteins, and apoptosis, but also act as cytoprotective factors against deleterious environmental stresses. Recent studies indicated that moderate overexpression of molecular chaperones could confer cells and tissues stress tolerance and provide beneficial effects on various pathological states associated with protein misfolding and protein aggregation. Mild heat shock, transfection of HSP genes, and some chemical compounds are the major means of overexpression of molecular chaperones. In this review, we summarize recent studies of chemical compounds that could induce or enhance the expression of molecular chaperones or HSPs.

Animals↗
PubMed2005

Vertical-torsional oscillations and dissociated bilateral horizontal gaze palsy in a patient with a pontine cavernous angioma.

We report the case of a 16 year old girl with vertical-torsional oscillations. She had a 4 year history of bilateral horizontal gaze palsy caused by a cavernous angioma in the medial part of the dorsal pons. She presented with vertical oscillopsia that had worsened during the past 3 months. Unilateral three dimensional eye movements and bilateral horizontal eye movements were recorded using a magnetic search coil method and direct current electro-oculography, respectively. She had vertical-torsional oscillations (average frequency: 3.0 Hz) leaving vertical saccades and pursuits intact. The average amplitudes of the vertical and torsional components were 2.0 degrees and 0.6 degrees , respectively. Her horizontal rapid eye movements were severely impaired; however, her horizontal pursuits and slow phases of vestibulo-ocular reflex were only partially impaired (gain<0.3, oculomotor range<+/-9 degrees ). Convergence and divergence were intact. Lesions involving the medial part of the dorsal pons and bilateral paramedian pontine reticular formation can induce vertical and torsional oscillations without disruption of vertical rapid eye movements.

Adolescent↗
PubMed2004

Aqueous levels of macrophage migration inhibitory factor and monocyte chemotactic protein-1 in patients with diabetic retinopathy.

AIMS: To investigate the relationship of aqueous macrophage migration inhibitory factor (MIF) and monocyte chemotactic protein-1 (MCP-1) levels with the clinical stage of diabetic retinopathy. METHODS: We assayed MIF and MCP-1 levels in aqueous humour samples obtained from 40 diabetic patients (49 eyes) and 24 non-diabetic patients (31 eyes) using enzyme-linked immunosorbent assay. According to the clinical stage of diabetic retinopathy, the diabetic patients were classified into non-diabetic retinopathy (11 eyes), non-proliferative diabetic retinopathy (14 eyes) and proliferative diabetic retinopathy (24 eyes). RESULTS: The aqueous levels of MIF (mean +/- sd) were 6.34 +/- 4.53 ng/ml in proliferative diabetic retinopathy, 3.22 +/- 1.71 ng/ml in non proliferative diabetic retinopathy, 1.25 +/- 0.96 ng/ml in non-diabetic retinopathy and 1.07 +/- 0.94 ng/ml in non-diabetic patients. Significant differences were found among these four groups (P < 0.0001). Aqueous MCP-1 levels were 1668.6 +/- 1442.3 pg/ml in proliferative diabetic retinopathy, 1528.6 +/- 1994.6 pg/ml in non-proliferative diabetic retinopathy, 690.2 +/- 402.1 pg/ml in non-diabetic retinopathy and 622.7 +/- 245.3 pg/ml in non-diabetic patients. Significant differences were also found among these four groups (P < 0.0001). After correcting for total aqueous protein, the ratios of MIF and MCP-1 to total protein remained significantly correlated with the clinical stage of diabetic retinopathy (P < 0.0001, P = 0.0004, respectively). The ratios of MIF to total protein significantly correlated with the ratios of MCP-1 to total protein in diabetic patients (r = 0.680, P < 0.0001). CONCLUSIONS: Aqueous MIF levels significantly correlated with aqueous MCP-1 levels and the clinical stage of diabetic retinopathy. The results suggest that MIF has a co-operative role with MCP-1 in the progression of diabetic retinopathy.

Adult↗
PubMed2003

NF-kappaB in epiretinal membranes after human diabetic retinopathy.

AIMS/HYPOTHESIS: Formation of epiretinal membranes (ERMs) in the posterior fundus results in progressive deterioration of vision. ERMs have been associated with numerous clinical conditions including proliferative diabetic retinopathy (PDR), but its pathogenic mechanisms are still unknown. This study was conducted to examine whether or not nuclear factor kappa B (NF-kappaB), a transcription factor that can be activated by various pathological conditions, is involved in the formation of ERMs after PDR. METHODS: ERM samples were obtained by vitrectomy from 22 cases with PDR aged 56+/-11 years with 18+/-10 years of diabetes and 15 cases with idiopathic ERM. They were processed for reverse transcription-polymerase chain reaction (RT-PCR) analysis. In addition, 5 ERM samples from PDR patients aged 51+/-16 years with 15+/-6 years of diabetes were processed for immunohistochemical analysis. RESULTS: NF-kappaB mRNA expression levels were higher (20 out of 22 cases vs. 9 out of 15 subjects in idiopathic ERM, p<0.05) in PDR subjects. Immunohistochemical analysis showed NF-kappaB protein expression in all the 5 ERMs derived from PDR patients, and that region was partially double-labelled with interleukin-8 (IL-8) and von Willebrand factor (vWF). CONCLUSIONS/INTERPRETATION: These results suggest a possibility that NF-kappaB is involved in the formation of ERMs after PDR, especially for the development of vascular endothelial cell component.

Adult↗
PubMed2003

Newly developed 3D endoscopic system: preliminary experience.

Although there have been earlier reports on the use of three-dimensional endoscopic systems in the gastrointestinal tract, real-time three-dimensional imaging has not previously been described. This paper presents experience in three cases with a novel endoscopic system for three-dimensional observation in clinical situations. Case 1 was a hyperplastic gastric polyp, the shape of which was considerably enhanced in comparison with two-dimensional endoscopic viewing. Case 2 was an advanced esophageal cancer, in which the sense of depth was improved in the esophagus. Case 3 was a depressed early gastric cancer, the shape of which was also enhanced. Between July 2001 and March 2002, three experienced endoscopists also used this new system in a further 34 patients. A three-dimensional endoscopic environment was visible with the system in all patients, and all of the endoscopists were able to obtain visual information regarding spatial depth. This experience suggests that the three-dimensional video-endoscopic system used here can be of value in gastrointestinal endoscopy.

Endoscopy, Gastrointestinal↗
PubMed2002

Correlation between serum phospholipase A(2) IIA levels and histological activity in patients with ulcerative colitis.

BACKGROUND AND AIMS: Phospholipase A(2) (PLA(2)) participates in the regulation of phospholipid metabolism and biosynthesis of eicosanoids, serum levels of PLA(2) are suggested to reflect the disease activity in patients with ulcerative colitis (UC). We examined the relationship between histological disease activity and serum levels of PLA(2) IIA and also clarified mucosal production sites of PLA(2) IIA by immunohistochemistry. PATIENTS AND METHODS: Serum samples from 44 patients with UC, 125 with Crohn's diseases (CD), and 68 controls were studied. Biopsy specimens of colonic mucosa obtained from 23 patients with UC were used for assessment of histological activity. The histological score was determined active (1) or inactive (0), and the sum of each histological score from ten segments of the large intestine was assessed as disease activity. The levels of PLA(2) IIA in sera were measured by a radioimmunoassay kit using a specific monoclonal antibody; immunohistochemical study was performed using the same monoclonal antibody. RESULTS: The serum PLA(2) IIA levels in patients with UC and CD were significantly higher than those of controls. Serum PLA(2) IIA levels in UC were closely correlated with histological disease activity. Immunohistochemical study showed the production of PLA(2) IIA by the polymorphonuclear cells, macrophages, and colonic epithelial cells. CONCLUSION: Serum PLA(2) IIA is a good candidate for assessing disease activity in UC as one of clinical laboratory tests.

Biomarkers↗
PubMed2001

Detection of Salmonella enteritidis in shell and liquid eggs using enrichment and plating.

Detection methods using various enrichment and plating media and immunoconcentration for Salmonella enteritidis in shell and liquid eggs were evaluated. For liquid egg samples naturally contaminated with S. enteritidis, pre-enrichment in 225 ml of buffered peptone water with cysteine followed by selective enrichment in 10 ml of tetrathionate broth was the superior, resulting in the detection of S. enteritidis in all samples on six of the seven types of selective agar substrate investigated. This enrichment procedure also enabled detection of S. enteritidis in most of artificially inoculated shell egg and pasteurized liquid egg samples.

Animals↗
PubMed2001

Anti-transforming growth factor-beta1 antibody transiently enhances DNA synthesis during liver regeneration after partial hepatectomy in rats.

The regulation of liver regeneration after partial hepatectomy (PHx) is complex and involves many different cytokines. We investigated the role of one of these, transforming growth factor-beta1 (TGF-beta1), an inhibitor of liver regeneration, in a Wistar male rat model, in which anti-TGF-beta1 antibody was injected immediately or 24 h after 70% PHx. Livers from treated animals contained an increased number of cells in S phase, according to 5-bromo-2'-deoxyuridine (BrdU) labeling 36 h after PHx. Antibody administration 24 h after PHx resulted in the highest peak of proliferation; moreover, peak MIB-5 labeling was also observed at that time. However, neither residual liver-weight-to-body-weight ratios nor regeneration rates differed significantly between any of the animals. Therefore, we also measured levels of serum TGF-beta1 and hepatocyte growth factor (HGF; an activator). With antibody administration at 0 or 24 h, TGF-beta1 levels were diminished at 24 or 36 h as compared with levels in control rats, but then rebounded, reaching a delayed peak at 48 or 72 h after PHx, respectively. Interestingly, there were also similar trends in HGF levels. These results indicate that TGF-beta1 may inhibit the G1 checkpoint, and serum TGF-beta1 concentration may influence HGF to regulate liver regeneration and to maintain homeostasis of proliferation after PHx.

Analysis of Variance↗
PubMed2001

Vascular compression as a cause of superior oblique myokymia disclosed by thin-slice magnetic resonance imaging.

PURPOSE: To describe a case of superior oblique myokymia in which thin-slice magnetic resonance imaging (MRI) appeared to show vascular compression of the trochlear nerve. METHODS: A 50-year-old woman presented with episodic monocular oscillopsia. Neuro-ophthalmologic examinations showed intermittent intorsional microtremor of her right eye, diagnosed as right superior oblique myokymia. Thin-slice (1.6 mm) MRI, using spoiled gradient recalled acquisition in the steady state, was employed to examine the trochlear nerve in its course through the ambient cistern. RESULTS: Imaging disclosed a branch of the posterior cerebral artery immediately adjacent to the right trochlear nerve. CONCLUSION: These magnetic resonance findings suggest that a cause of superior oblique myokymia may be vascular compression of the trunk of the trochlear nerve.

Cerebral Arteries↗
PubMed2001

Car-driving abilities of people with tetraplegia.

OBJECTIVES: To examine the relationship between the spinal cord injury (SCI) level, age, and car-driving ability in people with tetraplegia and to explore the association between car-driving ability and social activity. DESIGN: Retrospective clinical survey. SETTING: Rehabilitation center in Japan. PATIENTS: Sixty-two subjects with traumatic complete tetraplegia. INTERVENTIONS: Driving evaluation; comprehensive driver's training (muscle strengthening, transfer training, adjustment of equipment, on-road training); and questionnaire (car-driving status, employment, participation in sports). MAIN OUTCOME MEASURES: The SCI level (Zancolli's classification), age, functional status of activities of daily living (ADLs), and driving ability were obtained from the medical records. Vocational status and engagement in sports activities were investigated by questionnaire. RESULTS: The SCI level and age strongly influenced the patients' ability to drive a car independently. The highest neurologic level in which independent driving was achievable was C6A. Toilet transfer ability almost paralleled the ability to drive a car. Eighty-four percent of the people with tetraplegia who had a defined job could drive independently and 70% of the driving-independent individuals held a job. Half of driving-independent individuals participated in some sports activities. CONCLUSIONS: Toilet transfer ability is a reliable indicator for driver's training. Driving ability is an important factor that allows individuals with tetraplegia to participate in work and sports-related activities.

Activities of Daily Living↗
PubMed2001

Activated platelets in ulcerative colitis enhance the production of reactive oxygen species by polymorphonuclear leukocytes.

BACKGROUND: Although the number of activated platelets increases in the peripheral blood of patients with inflammatory bowel disease (IBD), the role of activated platelets in the polymorphonuclear leukocytes (PMN)-mediated mucosal injury in IBD remains unclear. In the present study, we used luminol-enhanced chemiluminescence (LCL) to examine the influence of platelets from patients with ulcerative colitis (UC) on the production of reactive oxygen species (ROS) by circulating PMN. METHODS: The proportion of P-selectin-positive activated platelets was determined using flow cytometry. PMN from patients with UC and normal controls were stimulated using phorbol 12-myristate 13-acetate with or without autologous platelets, anti-P-selectin monoclonal antibody and thrombin. Indicator PMN from a normal volunteer were stimulated using heterologous platelets from UC patients and normal controls, and LCL signals were registered every 60 sec for 240 min. RESULTS: The proportion of activated platelets was significantly increased in IBD patients. The level of ROS production by PMN did not significantly differ between UC patients and normal controls in the absence of a platelet-PMN interaction. Platelets from UC patients enhanced the amount of ROS produced by indicator PMN significantly more than those from normal controls. This effect was partly diminished by anti-P-selectin monoclonal antibody. CONCLUSIONS: Platelet activation in UC might be responsible for the secondary activation of PMN, which could account for the increase in PMN-mediated tissue injury associated with UC.

Adult↗
PubMed2001

Autoantibody to heat shock protein Hsp40 in sera of lung cancer patients.

Heat shock protein Hsp40 is a stress protein with chaperone activity and has a cooperative function with Hsp70 in mammalian cells. We examined the possible expression of Hsp40 in lung tumor tissues using immunoblotting and immunohistochemistry, and established an enzyme-linked immunosorbent assay (ELISA) method to detect IgG antibody to Hsp40 in the serum using purified human Hsp40. Sera were obtained from 130 normal subjects and 50 patients with lung cancer. Lung tumor tissues and cells specifically overexpressed Hsp40, and no such expression was detected in normal lung tissues. Compared with normal sera, significantly higher levels of autoantibody to Hsp40 were present in patients with lung cancer. The present study is the first to demonstrate overexpression of Hsp40 in human tumor tissue and the associated presence of autoantibody to Hsp40 in the serum. These results suggest that overexpression of Hsp40 in tumor cells may be recognized as a self-antigen.

Adenocarcinoma↗
PubMed2001

Characterization of a processed pseudogene of human psiHSP40 on chromosome 2q32.

A pseudogene for the human Hsp40 gene has been characterized (psiHSP40). The pseudogene sequence shows 90% similarity to the human Hsp40 mRNA at the nucleotide level. No introns were found in the region corresponding to the human Hsp40 cDNA, and two direct repeats flank this same region. Because of these features, the pseudogene can be classified as a processed pseudogene. PsiHSP40 was assigned to chromosome 2q32 by in situ hybridization. This is the first report of a pseudogene for a member of the DnaJ (Hsp40) family protein gene.

Base Sequence↗
PubMed2000

Identification of Mrj, a DnaJ/Hsp40 family protein, as a keratin 8/18 filament regulatory protein.

To elucidate the function of keratins 8 and 18 (K8/18), major components of the intermediate filaments of simple epithelia, we searched for K8/18-binding proteins by screening a yeast two-hybrid library. We report here that human Mrj, a DnaJ/Hsp40 family protein, directly binds to K18. Among the interactions between DnaJ/Hsp40 family proteins and various intermediate filament proteins that we tested using two-hybrid methods, Mrj specifically interacted with K18. Immunostaining with anti-Mrj antibody showed that Mrj colocalized with K8/18 filaments in HeLa cells. Mrj was immunoprecipitated not only with K18, but also with the stress-induced and constitutively expressed heat shock protein Hsp/c70. Mrj bound to K18 through its C terminus and interacted with Hsp/c70 via its N terminus, which contains the J domain. Microinjection of anti-Mrj antibody resulted in the disorganization of K8/18 filaments, without effects on the organization of actin filaments and microtubules. Taken together, these results suggest that Mrj may play an important role in the regulation of K8/18 filament organization as a K18-specific co-chaperone working together with Hsp/c70.

Antibodies↗