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S Katoh

Publications and source records attributed to S Katoh.

At least 19 recordsLinked to original sources
PubMed2006

Preservation of C7 spinous process does not influence the long-term outcome after laminoplasty for cervical spondylotic myelopathy.

Axial pain is one of the major complications after laminoplasty, and preservation of C7 spinous process during the procedure can reduce the axial pain. However, it has not been elucidated whether laminoplasty preserving the C7 spinous process can maintain neurological improvement for a long time. The purpose of our retrospective study was to investigate the long-term neurological outcome after open-door laminoplasty preserving the C7 spinous process for cervical spondylotic myelopathy (CSM). Clinical and radiological outcomes were analysed in 42 patients who underwent open-door laminoplasty preserving C7 spinous process and followed up for more than 5 years. Neurological function was evaluated by means of the Japanese Orthopaedic Association (JOA) scoring system for cervical myelopathy. Axial pain was assessed using a visual analog scale (VAS) at the last examination. Alignment and motion of the cervical spine were measured from radiographs, and magnetic resonance imaging (MRI) was used to evaluate postoperative compression at C7. The mean JOA score was 9.4 before surgery and 12.0 at the latest follow-up. The mean VAS score in 26 patients score was 9.7/100. No compression of the spinal cord was observed in any MRI at the latest follow-up. Preservation of the C7 spinous process does not influence the long-term outcome of CSM after laminoplasty. Although we did not have a comparative group, the procedure described here should be considered as the solution.

Adult↗
PubMed2006

The alpha2 type IX collagen tryptophan polymorphism is associated with the severity of disc degeneration in younger patients with herniated nucleus pulposus of the lumbar spine.

Tryptophan alleles in COL9A2 (Trp2) and COL9A3 (Trp3) have been linked to lumbar disc diseases in the Finnish population. Although such diseases consist of various pathogenetically different conditions, detailed analysis of each has not been well documented. The aim of this study was to clarify whether the collagen IX tryptophan alleles influence the symptomatic degeneration of the lumbar disc in Japanese patients with herniated nucleus pulposus. We performed a prospective study of 84 patients who underwent lumbar discectomy. The degree of disc degeneration was evaluated by magnetic resonance images in relation to the collagen IX genotype. Twenty patients (21.4%) had the Trp2 allele and no patients had the Trp3 allele. Patients under 40 years with the Trp2 allele showed more severe disc degeneration at the surgical level than did those without the Trp2 allele (odds ratio 6.00, P=0.043). In contrast, patients aged 40 years or over did not show significant association between disc degeneration and collagen IX genotype. Our results suggest that the Trp2 allele is an age-dependent risk factor for the severity of disc degeneration in younger patients with symptomatic herniated nucleus pulposus of the lumbar spine.

Adult↗
PubMed2006

Maternal smoking during pregnancy and genetic polymorphisms in the Ah receptor, CYP1A1 and GSTM1 affect infant birth size in Japanese subjects.

Genetic susceptibility to tobacco smoke might have relation to adverse pregnancy outcomes. To estimate the effects of maternal smoking and genetic polymorphisms on infant birth weight and length, we conducted a prospective cohort study of 293 women who delivered singleton live births in Sapporo, Japan. Birth weight and length were significantly lower among infants born to continuously smoking women having the aryl hydrocarbon receptor (AhR) wild type genotype (Arg/Arg; 211 g +/- 76 g; 1.2 cm +/- 0.4 cm, p < 0.01 and p < 0.01, respectively), the CYP1A1 variant genotype (m1/m2 + m2/m2; 170 g +/- 64 g, 0.8 cm +/- 0.3 cm, p < 0.01 and p < 0.05, respectively), or the GSTM1 null genotype (171 g +/- 58 g, 0.6 cm +/- 0.3 cm, p < 0.01 and p < 0.05, respectively). When combinations of these genotypes were considered, birth weight and length were significantly lower for infants of continuously smoking women in the AhR wild type + CYP1A1 variant group (315 g +/- 116 g; 1.7 cm +/- 0.6 cm, p < 0.01 and p < 0.01, respectively) and in the CYP1A1 variant + GSTM1 null group (237 g +/- 92 g; 1.3 cm +/- 0.5 cm, p < 0.05 and p < 0.01, respectively). These genotypes did not confer adverse effects among women who had never smoked; therefore, maternal smoking in combination with maternal AhR, CYP1A1 and GSTM1 genetic polymorphisms may adversely affect infant birth size.

Adult↗
PubMed2006

Extruded lumbar osseous endplate causing long-term radiculopathy in an adult: an endoscopic excision.

In this report, we described an adult case that had a long-term radiculopathy due to an extruded osseous endplate of the lumbar spine at the L5-S1 intervertebral disc level. The osseous material inside the extruded material was not absorbed, and it had continued compressing the nerve root for one year. Endoscopically, the bony fragment was successfully removed. After the surgery, the patient's symptom disappeared, and neurological deficits became normalized. In conclusion, we propose that surgical intervention should be taken into account for the treatment of HNP, when the extruded material contains bony fragment such as osseous endplate.

Adult↗
PubMed2005

Sex differences in cardiovascular and total mortality among diabetic and non-diabetic individuals with or without history of myocardial infarction.

AIMS/HYPOTHESIS: We investigated the associations of type 2 diabetes and a history of myocardial infarction (MI) with coronary heart disease, stroke, cardiovascular and total mortality, and whether these effects are different in men and women. METHODS: Study cohorts included 51,735 Finnish men and women aged 25-74 years. Smoking status and the history of MI and type 2 diabetes were recorded, and height, weight, blood pressure and serum cholesterol levels were measured at baseline. Additional data on the occurrence of diabetes and MI prior to baseline survey were obtained from national hospital discharge and drug registers through computerised register linkage. Mortality data were obtained from the national mortality register. RESULTS: During a mean follow-up period of 17.2 years, 9,201 deaths were recorded. Hazard ratios (HRs) for coronary mortality were 2.1, 4.0 and 6.4 among men with diabetes alone, men with MI alone, and men with diabetes and MI, respectively, compared with men with neither diabetes nor a history of MI. The corresponding HRs among women were 4.9, 2.5 and 9.4, respectively. The equivalent HRs for cardiovascular and total mortality were 2.2, 3.3 and 6.0, and 1.8, 2.3 and 3.7 in men, and 4.4, 2.4 and 6.5, and 3.2, 1.7 and 4.4 in women, respectively. Diabetic men and women had similar total mortality rates, whereas total mortality rates were markedly higher among men in the other three diabetes-MI categories. CONCLUSIONS/INTERPRETATION: Diabetes and MI markedly increase cardiovascular and all-cause mortality. In women, the association between diabetes and mortality was stronger than that between MI and mortality, whereas the converse was true among men.

Adult↗
PubMed2004

Elevated interleukin-18 levels in bronchoalveolar lavage fluid of patients with eosinophilic pneumonia.

BACKGROUND: Interleukin (IL)-18 can induce Th2 cytokine production particularly in collaboration with IL-2. Accumulation of Th2 cells and increased levels of Th2 cytokines are found in bronchoalveolar lavage fluid (BALF) from patients with eosinophilic pneumonia (EP). To evaluate the role of IL-18 in the pathogenesis of EP, we measured the concentration of IL-2, IL-12, IL-18, and Th2 cytokines in BALF from patients with EP. METHODS: The concentrations of interferon (IFN)-gamma, IL-2, IL-5, IL-10, IL-12, IL-13, and IL-18 in BALF were measured in patients with idiopathic acute eosinophilic pneumonia (AEP), with idiopathic chronic eosinophilic pneumonia (CEP), with sarcoidosis and healthy volunteers (HV). RESULTS: The BALF concentrations of Th2 cytokines, IL-5, IL-10, and IL-13, were higher in patients with EP than in sarcoidosis and control. The IL-2 level in BALF was higher in EP than in sarcoidosis and control. The IL-18 and IL-12 (p40 + p70) levels were higher in patients with EP than sarcoidosis, while the level of IL-12 (p70) was below the detection limit in patients with EP. There was a significant correlation between IL-2 level and both IL-5 and IL-13 in BALF of patients with EP. CONCLUSIONS: Our findings suggest that IL-18 may contribute to Th2 cytokine-dominant responses in patients with EP in collaboration with IL-2.

Adult↗
PubMed2004

Union of defects in the pars interarticularis of the lumbar spine in children and adolescents. The radiological outcome after conservative treatment.

Lumbar spondylolysis can heal with conservative treatment, but few attempts have been made to identify factors which may affect union of the defects in the pars. We have evaluated, retrospectively, the effects of prognostic variables on bony union of pars defects in 134 young patients less than 18 years of age with 239 defects of the pars who had been treated conservatively. All patients were evaluated by CT scans when first seen and more than six months later at follow-up. The results showed that the spinal level and the stage of the defects were the predominant factors. The site of the defects in the pars, the presence or development of spondylolisthesis, the condition of the contralateral pars, the degree of lumbar lordosis and the degree of lumbar inclination all significantly affected union.

Adolescent↗
PubMed2004

[Computed tomography findings of pulmonary benign lesion in the peripheral region].

We evaluated computed tomography (CT) images in 22 cases of pulmonary granulomas less than 2 cm in diameter which preoperative diagnosis was difficult. In these lesions, air-containing type, irregular undulation of margin, pleural indentation, accompanying shadow and involvement of pulmonary artery was observed on CT images. The accompanying shadow and the absence of pulmonary vein relate to the lesion may have relevance in pulmonary benign lesion.

Adult↗
PubMed2003

Accumulation of CCR4-expressing CD4+ T cells and high concentration of its ligands (TARC and MDC) in bronchoalveolar lavage fluid of patients with eosinophilic pneumonia.

BACKGROUND: Th2 cells are thought to be involved in eosinophilic inflammation of the lung. CC chemokine receptor 4 (CCR4) has been identified as a specific receptor for both thymus and activation-regulated chemokine (TARC) and macrophage-derived chemokine (MDC), and is preferentially expressed on Th2 cells. OBJECTIVE: Our aim was to evaluate the role of Th2 cells in the lung of patients with eosinophilic pneumonia (EP). METHODS: The concentrations of TARC, MDC, and interleukin (IL)-5 were measured in bronchoalveolar lavage fluid (BALF) by ELISA. Proportion of CCR4-expressing CD4+ T cells (CCR4+ CD4+ T cells) was determined by flow cytometry. RESULTS: TARC and MDC concentrations in BALF were higher in patients with EP than in normal subjects. The proportion of CCR4-expressing cells among CD4+ T cells was higher in BALF than in peripheral blood of patients with EP. There was a significant correlation between the number of CCR4+ CD4+ T cells and the levels of TARC, MDC, and IL-5 in BALF of patients with EP. CONCLUSIONS: Our data suggest that Th2 cells, which express CCR4 and its ligands (TARC and MDC), contribute to the pathogenesis of EP in the lung.

Adult↗
PubMed2003

[Pulmonary sequestration associated with fungal infections; report of a case].

A 45-year-old female was admitted to our hospital complaining of cough and purulent sputum. Enhanced chest computer tomography(CT) showed that abnormal mass shadow in left lower lobe of the lung and an aberrant artery originated from the discending aorta and penetrated the lesion. Left lower lobectomy was performed and intralobar sequestration was diagnosed. Moreover, fungus which were suspected Aspergillus were found in the cystic lesion. The postoperative course was uneventful and she was discharged.

Adult↗
PubMed2002

The hormonal responses of lipoprotein lipase activity and lipolysis in adipose tissue differ depending on the stage of the estrous cycle in female rats.

OBJECTIVE: This study was designed to elucidate whether there were differences in the hormonal responses of the parameters involving triacylglycerol (TG) deposition and mobilization in adipose tissue among the stages of the estrous cycle in female rats. MEASUREMENTS: Adipose tissue was obtained from the parametrial region in female rats at each stage of the estrous cycle. Lipoprotein lipase (LPL) activity in the extracts of acetone/ether powders of the tissues was measured as a parameter for TG deposition. Norepinephrine-stimulated lipolysis in isolated fat cells was measured as a parameter for TG mobilization. RESULTS: LPL activity changed periodically during the estrous cycle; the activity level was highest at diestrus, began to decrease at proestrus, reached a minimum at estrus, began to increase again at metestrus-1, and increased further at metestrus-2. At diestrus and proestrus, LPL activity was increased with an increase in plasma insulin levels, suggesting that plasma insulin was the predominant up-regulator of LPL. But at estrus, metestrus-1 and metestrus-2, LPL activity remained low even when plasma insulin levels were high, indicating that it was not up-regulated by plasma insulin. Norepinephrine-stimulated lipolysis in fat cells was high at estrus and metestrus-1 and low at diestrus. CONCLUSION: The hormonal responses of LPL activity and lipolysis in adipose tissue differed depending on the stage of the estrous cycle.

Adipose Tissue↗
PubMed2002

Elevated levels of thymus and activation-regulated chemokine (TARC) in pleural effusion samples from patients infested with Paragonimus westermani.

To investigate the pathogenic mechanisms of eosinophilic pleural effusion in patients with paragonimiasis, we measured the levels of various chemokines including thymus and activation-regulated chemokine (TARC), eotaxin, RANTES and IL-8 in pleural effusion samples. Samples were obtained from 11 patients with Paragonimus westermani infection, six patients with pleural transudate, eight with tuberculous pleurisy and five with empyema. High percentages of eosinophils were detected in pleural fluid (range 9-100%, median 81%) of patients with paragonimiasis. TARC concentrations in pleural effusions of paragonimiasis were markedly higher than those of other groups. Eotaxin levels were also higher in pleural effusions of paragonimiasis patients, although significant difference was noted only against transudate samples. There was a significant correlation between TARC concentrations and percentages of eosinophils, and between TARC and eotaxin concentrations in pleural effusion. There were also significant correlations between TARC concentration and the titre of anti-P. westermani IgG and between eotaxin concentration and the titre of anti-P. westermani IgG. Our findings suggest that TARC contributes to the pathogenesis of eosinophilic pleural effusion in paragonimiasis.

Aged↗
PubMed2001

Characteristics of velocity-controlled knee movement in patients with cervical compression myelopathy: what is the optimal rehabilitation exercise for spastic gait?

STUDY DESIGN: The isokinetic strength of knee extensors and flexors was measured at various controlled velocities in patients with spastic paraparesis caused by cervical compression myelopathy. OBJECTIVE: To evaluate leg function objectively in patients with myelopathy. SUMMARY OF BACKGROUND DATA: Cervical compression myelopathy causes varying degrees of spastic paresis in the legs and affects the activities of patients. However, the leg function characteristics of the patients have not been fully elucidated. METHODS: Velocity-controlled voluntary knee movements were studied in 39 patients (25 men and 14 women) with compression myelopathy. Their mean age was 60.2 years (range, 44-77 years). The patients were divided into Group A (ambulation without aid, n = 22) and Group AA (ambulation with aid, n = 17). Isometric peak torque values were measured in knee flexor and extensor muscles at 60 degrees of knee flexion, and isokinetic peak torque values were determined in maximal voluntary concentric movements of these muscles at constant angle velocities of 40 degrees, 80 degrees, 120 degrees, 160 degrees, and 180 degrees per second. The relative strength (percentage of isometric peak torque value) of the isokinetic motion was calculated at each velocity. RESULTS: In both groups, the relative strength decreased as the velocity increased, and the degree of reduced strength in the flexors at the high velocities of 160 degrees and 180 degrees per second was significantly greater in Group AA than in Group A (P < 0.05), whereas no significant difference was found in the extensors between the groups. CONCLUSIONS: The results indicate that isokinetic strength at a high velocity may reflect the severity of spastic paresis in the legs resulting from compression myelopathy.

Aged↗
PubMed2001

Determination of amino acid sequence responsible for suppression of bone resorption by serum calcium-decreasing factor (caldecrin).

We previously reported on the serum calcium-decreasing activity of recombinant protein factor referred to as caldecrin [Tomomura et al. (1995) J. Biol. Chem. 270, 30315-30321]. To address the mechanism of this serum calcium-decreasing activity, we investigated the effect of rat caldecrin on osteoclastic bone-resorbing activity. Wild-type caldecrin suppressed resorption pit formation by osteoclast on a dentine slice in a dose-dependent manner. The suppressive effect on the bone resorption was not affected by treatment of caldecrin with phenylmethyl sulfonyl fluoride or by use of protease-deficient mutant caldecrins. Recombinant procaldecrin (-13-239), and its fragments (-13-125), (1-111), (1-46), (47-111), and (126-239) were expressed as His-tagged thioredoxin fusion proteins and investigated for their ability to suppress bone resorption. The proform (-13-239) and fragment (-13-125) did not affect the suppressive activity, whereas fragments (1-111) and (126-239) did suppress the bone resorption. The bone-resorbing activity was also suppressed by fragment (47-111), not by fragment (1-46). Overlapping fragments (47-62), (47-79), (47-98), (56-111), (71-111), and (85-111) were compared for their suppressive activity. The fragments (47-62) and (85-111) did not affect the activity, but the other fragments suppressed the bone resorption. A synthetic peptide having the (71-79) sequence suppressed the bone resorption. These results suggest that amino acid sequence corresponding to rat caldecrin (aa 71-79) is responsible for the suppression of bone resorption by caldecrin.

Amino Acid Sequence↗
PubMed2001

Endothelin-1 stimulates cardiomyocyte injury during mitochondrial dysfunction in culture.

To understand the pathophysiological role of endothelin-1 in the failing heart, we constructed a cellular mitochondrial impairment model and demonstrated the effect of endothelin-1. Primary cultured cardiomyocytes from neonatal rats were pretreated with rotenone, a mitochondrial complex I inhibitor, and the cytotoxic effect of endothelin-1 on the cardiomyocytes was demonstrated. Rotenone gradually decreased the pH of the culture medium with incubation time and caused slight cell injury. Endothelin-1 markedly enhanced the effect of rotenone that decreased the pH of the medium and enhanced cellular injury. The enhancement of the decrease in pH and cell injury induced by endothelin-1 was counteracted by the endothelin ET(A) receptor antagonist BQ123 or by maintaining the pH of the medium by the addition of 50 mM HEPES. Endothelin-1 markedly increased the uptake of 2-deoxyglucose and lactic acid production when the cardiomyocytes were pretreated with rotenone. These findings suggest that the stimulation of glucose uptake and anaerobic glycolysis followed by the increase in lactic acid accumulation in cardiomyocytes under the condition of mitochondrial impairment may be involved, at least in part, in the cellular injury by endothelin-1. Moreover, these findings suggest the possibility that the effect of endothelin-1 on myocardium is reversed by the condition of the mitochondria, and endogenous endothelin-1 may deteriorate cardiac failure with mitochondrial dysfunction. This may contribute to clarify the beneficial effect of endothelin receptor blockade in improving heart failures.

Animals↗
PubMed2001

Mechanism of bovine serum albumin aggregation during ultrafiltration.

Protein fouling is a critical problem for ultrafiltration. In this study, we adopted bovine serum albumin (BSA) as a model protein and polysulfone membrane as a typical ultrafiltration membrane. We then investigated the factors of the protein denaturation and aggregation, such as stirring shear stress and intermolecular exchange of disulfide during ultrafiltration, and discussed the BSA fouling mechanism. Fourier transform-infrared analysis revealed that magnetic stirring did not cause any difference in the secondary structural change of BSA gel-like deposits on the ultrafiltration membrane. BSA aggregates were collected from BSA gel-like deposits on the ultrafiltration membrane by centrifugation. Polyacrylamide gel electrophoresis in SDS analysis of BSA aggregates proved that the major binding of the BSA aggregates involved intermolecular disulfhydryl binding and that capping the free thiol group in BSA molecules with cysteine induced a remarkable decrease in the amount of the BSA aggregates during ultrafiltration. We concluded that one of the main factors in the BSA aggregation during ultrafiltration is the intermolecular exchange of disulfide through cysteinyl residue. We also found that the BSA aggregation caused a decrease in alpha-helix from 66% to 50% and an increase in beta-sheet from 20% to 36%, which was presumably because the cysteine residues associated with the intermolecular disulfide bonds had been located in alpha-helices.

Animals↗
PubMed2001

Slippage mechanism of pediatric spondylolysis: biomechanical study using immature calf spines.

STUDY DESIGN: This study analyzed the skeletal-age-dependent strength of the lumbar growth plate to resist anterior shearing forces using the MTS system in the immature calf spine with pars defects. OBJECTIVE: To clarify the pathomechanism of the skeletal-age-dependent incidence of slippage in pediatric patients with pars defects by comparing the strength of the lumbar growth plate among three skeletal age groups. SUMMARY OF BACKGROUND DATA: Isthmic spondylolisthesis occurs and progresses more frequently during the growth period, whereas it is rare afterward. However, little evidence has been demonstrated to elucidate the etiology. METHODS: For this study, 15 lumbar functional spine units were divided into three groups according to their skeletal ages. Five were from neonates (Group 1), five from calves approximately 2 months old (Group 2), and five from calves about 24 months old (Group 3). An anterior shearing force was applied to each specimen until failure, after bilateral pars defects were created. Failure load (newtons) and displacement at failure (millimeters) were calculated from the load-displacement curve. The site of failure was confirmed by plain radiograph. RESULTS: All 15 functional spine units failed at the growth plate. The failure load was 242.79 +/- 46.05 N in Group 1, 986.40 +/- 124.16 N in Group 2, and 2024.54 +/- 245.53 N in Group 3. Statistically significant differences were found among the three groups (P < 0.05). The displacement at failure was 7.52 +/- 1.84 mm in Group 1, 11.10 +/- 2.30 mm in Group 2, and 8.15 +/- 2.66 mm in Group 3. There were no significant differences among the groups. CONCLUSIONS: The results indicate that the strength of the growth plate, the weakest link in this model, against anterior shearing forces depends on the skeletal maturity, and that the biomechanical weakness of the growth plate plays an important role in the slippage mechanism.

Aging↗