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S Nakaji

Publications and source records attributed to S Nakaji.

At least 19 recordsLinked to original sources
PubMed2006

Effects of rugby sevens matches on human neutrophil-related non-specific immunity.

AIMS: To evaluate the influences of the accumulative effect of two consecutive rugby sevens matches (Sevens) on aspects of human neutrophil-related non-specific immunity. METHODS: In seven players participating in the Japan Sevens, neutrophil reactive oxygen species (ROS) production capability and phagocytic activity were measured using flow cytometry, and serum opsonic activity (SOA) was assessed by measuring neutrophil ROS using the peak height of lucigenin-dependent chemiluminescence before and after two consecutive matches. RESULTS: ROS showed no change immediately after the first match, and had significantly (P<0.05) increased 4 h later, but showed a decrease after the second match. Phagocytic activity showed no change immediately after the first match, but had significantly (P<0.01) decreased 4 h later, and showed a further decrease after the second match, although it was not significant. SOA significantly (P<0.01) increased after the first match, and still maintained its high 4 h later, but decreased after the second match. ROS production capability, phagocytic activity and SOA significantly (P<0.01) decreased after the second match. CONCLUSIONS: When rugby players play two consecutive Sevens matches, the exercise loading is thought to be hard, similar to that experienced during a marathon race and intensive or long training in a training camp, although the expected changes were not seen after the first match. Differences between after the first and the second matches may be due to the "cumulative effect".

Adult↗
PubMed2006

Pattern of dietary fiber intake among the Japanese general population.

OBJECTIVES: To evaluate the dietary fiber (DF) intake pattern among the Japanese general population. DESIGN: We performed a dietary survey among the general population in northern Japan to evaluate the intake patterns. DF intake was calculated by substituting the DF content of each food in the Dietary Fiber Table for the intake of each food from this dietary survey. SUBJECTS: Five hundred and seventy-seven subjects participated in the study, 198 men and 379 women. RESULTS: In subjects with higher DF intakes the origins of the DF that were from all food groups, but with the notable exception of rice. The contribution of the seaweed group was of particular interest. From multiple regression analysis, as for food group, seaweeds showed the highest positive correlation with DF intake in both genders, followed by vegetables, pulses, fruits. On the other hand, rice showed the negative correlation with DF intake in both genders. As for life factor, body mass index showed the negative correlation with DF intake in women. CONCLUSION: Seaweed, a typical Japanese food, was most related to the increase in DF intake for the Japanese general population, whereas rice, the Japanese staple, had a small influence on decreased DF intake.

Adult↗
PubMed2006

Reversible splenial lesion with restricted diffusion in a wide spectrum of diseases and conditions.

OBJECTIVE: Reversible lesion in the central area of the splenium of the corpus callosum (SCC) is a unique phenomenon occurring particularly in patients with encephalitis or encephalopathy and in patients receiving antiepileptic drugs (AED). We report MR imaging findings, clinical courses, and outcomes in eight patients with various diseases and conditions. MATERIALS AND METHODS: Eight patients with a reversible SCC lesion with transiently restricted diffusion were reviewed retrospectively. Diseases and conditions that were associated with a reversible lesion included epilepsy receiving AED (n=1), seizure from eclampsia receiving AED (n=1), mild infectious encephalitis (n=2), hypernatremia resulting in osmotic myelinolysis (n=1), and neoplasm (n=3) such as acute lymphocytic leukemia, spinal meningeal melanocytoma, and esophageal cancer. We evaluated MR imaging findings and clinical findings. RESULTS: Seven patients had isolated SCC lesions; one patient with osmotic myelinolysis showed additional parenchymal lesions. The reversible SCC lesion shape was oval (n=6) or extended (n=2). The mean apparent diffusion coefficient value of the splenial lesion was 0.40+/-0.16 x 10-3 mm2/s, ranging from 0.22 to 0.64 x 10-3 mm2/s. In a patient with osmotic myelinolysis, additional white matter lesions, shown as restricted diffusion, were revealed as not reversible on follow-up MR imaging. Neurological courses and outcomes were good in seven patients with isolated SCC lesions, but poor in one with osmotic myelinolysis. CONCLUSION: Reversible SCC lesion with restricted diffusion is apparent in a wide spectrum of diseases and conditions. Neurological courses and outcomes are good, particularly in patients with isolated SCC lesions. Knowledge of MR imaging findings and the associated spectrum of diseases and conditions might prevent unnecessary invasive examinations and treatments.

Adolescent↗
PubMed2004

Effect of incorporating low intensity exercise into the recovery period after a rugby match.

BACKGROUND: The psychological and physiological condition of athletes affect both their performance in competitions and their health. Rugby is an intense sport which appears to impose psychological and physiological stress on players. However, there have been few studies of the most appropriate resting techniques to deliver effective recovery from a match. OBJECTIVES: To compare the difference in recovery after a match using resting techniques with or without exercise. METHODS: Fifteen Japanese college rugby football players were studied. Seven performed only normal daily activities and eight performed additional low intensity exercise during the post-match rest period. Players were examined just before and immediately after the match and one and two days after the match. Blood biochemistry and two neutrophil functions, phagocytic activity and oxidative burst, were measured to assess physiological condition, and the profile of mood states (POMS) scores were examined to evaluate psychological condition. RESULTS: Immediately after the match, muscle damage, decreases in neutrophil functions, and mental fatigue were observed in both groups. Muscle damage and neutrophil functions recovered with time almost equally in the two groups, but the POMS scores were significantly decreased only in subjects in the low intensity exercise group. CONCLUSIONS: Rugby matches impose both physiological and psychological stress on players. The addition of low intensity exercise to the rest period did not adversely affect physiological recovery and had a significantly beneficial effect on psychological recovery by enhancing relaxation.

Activities of Daily Living↗
PubMed2004

Effects of exercise on the physical condition of college rugby players during summer training camp.

OBJECTIVES: To determine the effects of exercise training on physical condition in 25 college rugby players during a summer training camp, and to compare these variables by the different players' positions. METHODS: Changes in body composition parameters and blood biochemistry were examined before and after a summer training camp. RESULTS: Body weight and percentage body fat did not change significantly during the camp. There were significant decreases in levels of serum total cholesterol, triglycerides, phosphate, uric acid, and immunoglobulin G and M. In contrast, there were significant increases in levels of serum potassium, markers of renal, hepatic, and muscular damage (BUN, GOT, GPT, LDH, CK), and complement C4. Comparison of the changes in biochemical parameters between rugby players playing in different positions showed a significant increase in serum albumin level in the forwards, and significant decreases in serum triglyceride and sodium levels in the backs. The magnitude of change in serum LDH during the camp was significantly greater (p<0.05) for the forwards than for the backs. CONCLUSIONS: These data suggest that, in rugby players attending a 20 day camp, exercise training resulted in muscular damage, loss of electrolytes due to sweating, and changes in immune function. Backs exhibited a higher rate of fat metabolism and loss of electrolytes than forwards, possibly because they did more running during the camp. In contrast, forwards experienced more physical contact, performed more physically strenuous exercise, and exhibited higher levels of muscular damage and tissue protein degradation.

Adult↗
PubMed2004

Position related analysis of the appearance of and relationship between post-match physical and mental fatigue in university rugby football players.

OBJECTIVE: The relationship between physical and mental fatigue in rugby players after a match was examined, taking into account the position played. METHODS: The Profile of Mood State (POMS) test, blood biochemical parameters, and serum opsonic activity were measured for 37 university rugby football players before and after a match. RESULTS: There were no differences in parameter changes except for blood urea nitrogen (a marker for protein catabolism) between the forwards and the backs. Regarding correlation between physical and mental fatigue, in forwards, changes in POMS scores showed a positive correlation with changes in the levels of enzymes of skeletal muscle origin, such as glutamate oxaloacetic transaminase (GOT) and lactate dehydrogenase (LDH), and free fatty acid (FFA) level and white blood cell count (for example, in the Total Mood Disturbance (TMD) score, Spearman's correlation coefficient was 0.417 and p<0.05 with GOT, 0.413 and p<0.05 with LDH, 0.462 and p<0.05 with FFA, and 0.442 and p<0.05 with white blood cell count). In backs, changes in the POMS scores showed a positive correlation with changes in the levels of lipid related parameters such as FFA and total cholesterol (for example, as regards the TMD score, Spearman's correlation coefficient was 0.481 and p<0.05 with FFA, and 0.550 and p<0.05 with total cholesterol), and showed a negative correlation with change in blood glucose level (TMD score, -0.517 and p<0.05). CONCLUSIONS: The different exercise loading of the position played during a rugby match may cause differences in the relationship between physical and mental fatigue.

Adult↗
PubMed2004

Adverse effects of energy restriction on changes in immunoglobulins and complements during weight reduction in judoists.

AIM: A preliminary study to investigate the combined effects of dietary restriction and weight reduction through exercise on markers of immune function in college judoists before and after a single competition. METHODS: Forty-nine judoists participated in the study. Thirty-eight athletes combined exercise and dietary restriction (WR group), and 11 athletes did not require dietary restriction (EX group). Changes in anthropometric parameters, energy intake, concentrations of serum immunoglobulins and complements, and white blood cell counts were assessed at 4 time points: 20 days (pre-values), 4 days and 1 day before the competition, and 7 days after the competition. RESULTS: Compared with pre-values, the WR group exhibited significant decreases in body weight (-2.8 kg at 1 day before) and fat free mass (-1.7 kg at 1 day before); there were no changes in these variables in the EX group. The WR group exhibited significant decreases in IgG, IgM and C3 at 7 days after the competition (all p<0.01). In the EX group, significant decreases in IgM and C3 (both p<0.05) were observed at 7 days after the competition, though to a lesser degree than in the WR group. CONCLUSIONS: Energy restriction seemed to exacerbate alterations in immune markers such as immunoglobulin and complement induced by vigorous exercise at 7 days after a competition. Although the changed values were still within normal limits, we hypothesize that the potential cumulative effect of these changes over many competitions in 1 year might well induce abnormal levels with a possibly harmful clinical effect on judoists.

Adult↗
PubMed2003

Explanations for the smoking paradox in Japan.

The prevalence of cigarette smoking among Japanese men has been consistently high compared with Western males over the past 30 years. However, during the same period, the incidence of and mortality rates for lung cancer have consistently been lower in Japan than in Western countries ('Japanese smoking paradox'). The odds ratio/relative risk of cigarette smoking for lung cancer mortality/incidence relative to the same number of cigarettes smoked per capita in Japan, were apparently lower than those in Western countries. This must be the cause driving the 'Japanese smoking paradox'. Furthermore, low carcinogenic ingredients in Japanese cigarettes and a congenitally-related resistance to smoking-related lung carcinogenesis emerged as the main factors which have brought the 'Japanese smoking paradox'.

Adolescent↗
PubMed2003

Development of predictive equations for body density of sumo wrestlers using B-mode ultrasound for the determination of subcutaneous fat thickness.

OBJECTIVE: To develop an equation for predicting the body density of sumo wrestlers. METHODS: The following were measured: subcutaneous fat thickness measured at nine sites using B-mode ultrasound equipment; circumference at seven sites; hand to leg bioelectrical impedance. The subjects consisted of 24 college sumo wrestlers (mean age 19.7 years, mean body weight 111.2 kg) and 24 matched obese controls (mean age 19.1 years and mean body weight 111.2 kg). In addition, body density was measured by the underwater weighing method, and the percentage of fat was calculated from the measured body density. RESULTS: Linear regression analysis was used to estimate the relation between body density and other variables, and a predictive equation for the body density was derived: y = 1.088-0.00036 x (fat thickness at nine sites) (r(2) = 0.90) for the sumo wrestler group and y = 1.083-0.00033 x (fat thickness at nine sites) (r(2) = 0.91) for the control group. A multiple regression analysis was performed using the body density as the objective variable, and other measured items as the explanatory variables. This was used to derive a predictive equation: y = 1.121-0.00038 x (fat thickness of abdomen)-0.00043 x (circumference of hips)-0.00142 x (fat thickness of triceps) (r(2) = 0.94) for the sumo wrestler group, and y = 1.076-0.00070 x (fat thickness of abdomen)-0.00140 x (fat thickness of tibialis) (r(2) = 0.91) for the control group. The difference between the two equations was due to the difference in body fat distribution. Neither of these predictive equations is applicable to non-overweight non-athletes. CONCLUSION: This is the first predictive equation developed for the body density of sumo wrestlers.

Adipose Tissue↗
PubMed2003

Helicobacter pylori water soluble surface proteins prime human neutrophils for enhanced production of reactive oxygen species and stimulate chemokine production.

BACKGROUNDS/AIMS: Chronic gastritis induced by Helicobacter pylori is characterised by considerable neutrophil infiltration into the gastric mucosa without mucosal invasion of bacteria. Bacteria have different characteristics with respect to their ability to stimulate human neutrophils to produce reactive oxygen species and chemokines. The aim of this study was to examine the effects of H pylori water extracts on the oxidative burst and chemokine production of human neutrophils. METHODS: Helicobacter pylori cells were extracted by harvesting into distilled water and centrifugation. Neutrophils were incubated with H pylori water extracts and the production of reactive oxygen species was measured using luminol dependent chemiluminescence (LmCL). In addition, the concentrations of chemokines (interleukin 8 (IL-8), macrophage inflammatory protein 1-alpha (MIP1-alpha), and MIP1-beta) were measured by enzyme linked immunosorbent assay. Neutrophils were also stimulated by opsonised zymosan (OZ) after preincubation with H pylori water extracts. RESULTS: Helicobacter pylori water extracts alone induced only a weak oxidative burst but preincubation of neutrophils with water extracts dose dependently enhanced the LmCL response stimulated by OZ. Helicobacter pylori water extracts also stimulated neutrophil IL-8 production, although MIP-1beta production was only stimulated weakly, and MIP-1alpha was not stimulated at all. CONCLUSIONS: Helicobacter pylori products in water extracts may have a role in the activation and migration of neutrophils, which results in enhanced oxidative damage to gastric mucosa. These findings may explain the pathology of H pylori induced gastritis, in which there is little invasion of bacteria into the gastric mucosa.

Bacterial Outer Membrane Proteins↗
PubMed2001

Dietary fiber showed no preventive effect against colon and rectal cancers in Japanese with low fat intake: an analysis from the results of nutrition surveys from 23 Japanese prefectures.

BACKGROUND: Since Fuchs' report in 1999, the reported protective effect of dietary fiber from colorectal carcinogenesis has led many researchers to question its real benefit. The aim of this study is to evaluate the association between diet, especially dietary fiber and fat and colorectal cancer in Japan. METHODS: A multiple regression analysis (using the stepwise variable selection method) was performed using the standardized mortality ratios (SMRs) of colon and rectal cancer in 23 Japanese prefectures as objective variables and dietary fiber, nutrients and food groups as explanatory variables. RESULTS: As for colon cancer, the standardized partial correlation coefficients were positively significant for fat (1,13, P = 0.000), seaweeds (0.41, P = 0.026) and beans (0.45, P = 0.017) and were negatively significant for vitamin A (-0.63, P = 0.003), vitamin C (-0.42, P = 0.019) and yellow-green vegetables (-0.37, P = 0.046). For rectal cancer, the standardized partial correlation coefficient in fat (0.60, P = 0.002) was positively significant. Dietary fiber was not found to have a significant relationship with either colon or rectal cancers. CONCLUSIONS: This study failed to show any protective effect of dietary fiber in subjects with a low fat intake (Japanese) in this analysis, which supports Fuchs' findings in subjects with a high fat intake (US Americans).

Colonic Neoplasms↗
PubMed2001

Locus of a virus neutralization epitope on the Japanese encephalitis virus envelope protein determined by use of long PCR-based region-specific random mutagenesis.

We prepared recombinant Japanese encephalitis (JE) virus populations possessing random mutations at the envelope (E) protein region by a long PCR-based method. Neutralization-resistant mutants were selected from these populations by application of JE-specific virus neutralizing monoclonal antibody (mAb) 503, which possessed a 51,200-fold neutralization titer. We classified the mutants into three groups, each bearing two amino acid alterations at the E protein region: 52, Gln-Arg, and 136, Lys-Glu; 136, Lys-Glu, and 275, Ser-Pro; and 126, Ile-Thr, and 136, Lys-Glu, respectively. Three different genetically engineered variants, each bearing a single mutation, 126, Ile-Thr; 136, Lys-Glu; and 275, Ser-Pro, respectively, showed partial but not complete recovery of reactivity to mAb 503. Our results indicate that the amino acid substitutions at amino acid positions 52, 126, 136, and 275 altered the structure of the neutralization epitope for mAb 503 on the E protein. All these mutations were clustered at the junction of domains I and II of the E protein and it is likely that the epitope for mAb 503 is composed of at least E(0)-e, D(0)-a, and k strands of the E protein. We also demonstrated the efficacy of the long PCR-based recombinant virus technique as a useful tool for the creation of a variety of mutants bearing random mutations at targeted areas of the virus genome.

Animals↗
PubMed2001

Ecabet sodium inhibits the ability of Helicobacter pylori to induce neutrophil production of reactive oxygen species and interleukin-8.

The pathogenic role of human neutrophils has been implicated in Helicobacter pylori-associated gastritis. Ecabet sodium, a locally acting antiulcer drug, has anti-H. pylori actions. The aim of this study was to examine the effects of ecabet on the ability of H. pylori to stimulate human neutrophils. H. pylori were added to 1 x 10(5) neutrophils and incubated for 30 min in the presence of ecabet. Bacterial suspensions which had been incubated with ecabet for 30 min were also used to stimulate neutrophils. The intracellular production of reactive oxygen species was measured with a FACScan. Bacterial suspensions were also added to neutrophils in the presence of ecabet and incubated at 37 degrees C for 12 h to measure interleukin (IL)-8 production by enzyme-linked immunosorbent assay. The mean fluorescence intensity was found to be attenuated dose-dependently by ecabet (P < 0.01). Ecabet also inhibited IL-8 production by neutrophils in a dose-dependent manner (P < 0.001). Bacteria with prior incubation with ecabet induced significantly lower IL-8 production than those without this incubation (P < 0.05). Ecabet sodium has preventive effects on the ability of H. pylori to stimulate human neutrophils. It may lead to reduced gastritis activity and decreased oxidative damage of the gastric mucosa in H. pylori-associated gastritis.

Abietanes↗
PubMed2001

Evaluation of the association between serum anti-Lewis X antibody and inflammatory infiltration into the gastric mucosa infected with Helicobacter pylori.

BACKGROUND: Lipopolysaccharides of Helicobacter pylori have an antigenic structure that mimics Lewis X occurring in gastric mucosa. The pathogenic role of antigenic mimicry in Helicobacter pylori-induced gastritis has been of recent interest. AIM: To examine whether this molecular mimicry affects gastric mucosal inflammation in patients infected with Helicobacter pylori. PATIENTS: A total of 59 patients (mean age 58.0 years, 35 males, 24 females) were studied. METHODS: Serum samples were collected to measure IgG antibodies to Helicobacter pylori and Lewis X. Biopsy specimens were obtained from the antrum and corpus for the grading of gastritis. Correlation coefficients between serum Lewis X antibody titre and histological grades of inflammatory infiltration were determined. RESULTS: There was no significant correlation between anti-Lewis X antibody titre and the grade of mononuclear or polymorphonuclear cell infiltration. High titre of anti-Lewis X antibody was seen only in patients who had increased inflammatory infiltration in the corpus. CONCLUSIONS: Serum anti-Lewis X antibody, possibly induced by Helicobacter pylori infection, does not seem to play a major role in gastric mucosal inflammation in patients with Helicobacter pylori infection.

Female↗
PubMed2001

Differences in carcinogenesis by the length of carcinogen exposure period in rat colon.

To clarify the carcinogenic factors--whether it is the kind of carcinogen or their length of exposure--that determine whether colorectal cancer develops from an adenoma or develops de novo in the absence of an adenoma, we histopathologically analyzed a total of 229 rat colon tumors induced by administration of 1,2-dimethyl-hydrazine (DMH) or N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) for three or 15 weeks. In the three-week-exposure groups, 71% of DMH-induced carcinomas and 82% of MNNG-induced carcinomas coexisted with low-grade dysplasia (adenomatous remnant). However, in the 15-week-exposure groups, lowgrade dysplasia was observed in only 10% of DMH-induced and 27% of MNNG-induced carcinomas. Even in the tumors smaller than 20 mm3, it was observed in only 10% of DMH-induced and 32% of MNNG-induced carcinomas. Furthermore, carcinomas without low-grade dysplasia predominated from the initial period of tumor occurrence. Next, we investigated association of K-ras and APC gene mutations with these carcinogenesis patterns in 80 tumors. K-ras mutations were not detected in any tumors induced by three weeks of exposure. However, in the 15-week-exposure groups, this mutation was observed in 57% of DMH-induced tumors and 13% of MNNG-induced tumors. APC mutations in the region homologous to the human mutation cluster region were observed in only 6% of tumors. Thus, our results suggest that the carcinogenesis patterns in rat colon are dependent on the length of exposure to carcinogen and that K-ras mutations were partly involved in a subset of them.

1,2-Dimethylhydrazine↗
PubMed2001

Changes in intraluminal pressure in rat large intestines with aging and effects of dietary fiber.

Changes in intraluminal pressure in rat colon with aging and with the effects of dietary fiber were measured. A pressure sensor was inserted into the rat large intestine under endoscopic guidance. The intraluminal pressure curve in the colon was recorded, and the motility index was calculated by this curve. The rats were divided into three groups with a fiber-free diet, a cellulose diet (10% w/w), or a pectin diet (10% w/w). Intraluminal pressure was measured in the proximal, middle, and distal colon at 2, 4, 8, 12, and 16 months after birth. Intraluminal pressure in three sites increased with age and decreased in the latter half of the study. The motility index was lower during the course in the fiber groups, especially the pectin group more than the nonfiber group. This result suggests that long-term ingestion of dietary fiber might have a prophylactic effect on the development of diverticula.

Age Factors↗
PubMed2001

Current topics on immunoadsorption therapy.

Immunoadsorption therapy has become popular for the treatment of various autoimmune diseases as the number of clinically available immunoadsorption columns increases. Immunoadsorption columns for plasma perfusion or direct hemoperfusion available for clinical use such as the Immusorba TR and PH, Selesorb, Prosorba, Immunosorba, Ig-Therasorb, and Medisorba MG are reviewed in the first part of this article. The peptide columns which immobilize peptides as the ligands are described in the second half. The peptide column has the potential to deliver specific adsorbents if a peptide is appropriately designed to remove the pathogenic substances specifically responsible for the given disease.

Autoimmune Diseases↗