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H Imaeda

Publications and source records attributed to H Imaeda.

At least 19 recordsLinked to original sources

Urinary pyrimidine analysis in healthy newborns, infants, children, adults and patients with congenital metabolic diseases.

BACKGROUND: In previous reports, the reference range for urinary pyrimidine was determined on the basis of a small number of samples, with data for only a few patients being reported. In the present study, we measured urinary pyrimidine compounds in 25 healthy newborns, 33 healthy infants, 130 healthy children and 166 healthy adults. In addition, we also analyzed urinary pyrimidine compounds in various patients with abnormal pyrimidine metabolism, such as congenital pyrimidine metabolism disorders and urea cycle disorders. METHODS: We analyzed urines by high-performance liquid chromatography with column switching. Analyses were performed with both a reverse-phase column and an anion-exchange column. The columns were connected by a column switch, with all systems being controlled automatically by a computerized system controller. RESULTS: The excretion of pyrimidine compounds in patients with abnormal pyrimidine metabolism (containing heterozygotes) was out of our reference ranges. CONCLUSIONS: These results suggest that urinary pyrimidine analysis is a useful index for the diagnosis of pyrimidine metabolism disorders, urea cycle disorders and these heterozygotes. Based on this large-group analysis of healthy individuals, we were able to determine the reference ranges of urinary orotic acid, dihydrouracil and uracil for each age group.

Adolescent↗

Analysis of clinical course and long-term prognosis of surgical and nonsurgical patients with intestinal Behçet's disease.

OBJECTIVE: Much remains unknown about the pathogenesis of intestinal Behçet's disease. The majority of these patients are treated with surgical intervention, although it has been recently reported that a number of medical treatments are sometimes effective. Only few studies, however, have ever been undertaken to analyze the long-term prognosis of this disease. In this study, we analyzed the clinical course and the recurrences after initial therapy in patients with intestinal Behçet's disease. METHODS: We investigated 20 patients (surgical group, n = 8; nonsurgical group, n = 12) for whom the clinical courses were known for > or = 2 yr (2-23 yr). RESULTS: The surgical group tended to have higher rates of complications such as ocular and ileal lesions than the nonsurgical group. In the surgical group, 75% of the patients recurred (and were readmitted) within 2 yr, and 37.5% of the patients required reoperation for intestinal obstruction because of ulcer at the anastomosis. The percentage of peripheral CD8+ DR+ lymphocytes in the recurrent group (10.4% +/- 2.5%) was significantly higher than that in the nonrecurrent group (4.3% +/- 1.2%, p < 0.05). CONCLUSIONS: Our results indicate that more extensive disease involving the ileum and ocular lesions are markers of severity and progression to surgical crisis, and that patients requiring surgery suffer more frequent recurrences. Furthermore, an increased percentage of peripheral CD8+ DR+ lymphocytes may be a risk factor for disease recurrence.

Adolescent↗

Hereditary orotic aciduria heterozygotes accompanied with neurological symptoms.

We report a family with hereditary orotic aciduria heterozygotes. A 3-year-old boy who had been diagnosed as having cerebral palsy and mental retardation presented himself with an increase in excretion of urinary orotic acid. Enzymatic studies revealed that the boy and his healthy mother were hereditary orotic aciduria heterozygote carriers. We can not prove that this pyrimidine disorder caused his neurological symptoms, but his pyrimidine nucleoside supply may have been insufficient in his neonatal period.

Cerebral Palsy↗

[Pneumoperitoneum with systemic sclerosis].

We report a case of systemic sclerosis (SSc) complicated with benign pneumoperitoneum without apparent pneumatosis cystoides intestinalis (PCI). A 43-year-old woman was admitted to our hospital because of prominent abdominal distension in April 1997. Raynaud's phenomenon has been detected since 1991. She was suffering from recurrent diarrhea, constipation, and subileus. The diagnosis of SSc was made in 1996 based on the sclerosis in her face, forearms, and chest, and hypomotility of the esophagus. On admission, she presented no signs of peritoneal irritation. The laboratory data revealed that white blood cell count was 7,400/mm3 and C-reactive protein was 0.1 mg/dl. Chest and abdominal roentgenograms showed massive free air under the diaphragm, dilatation of small and large intestine, and air-fluid level. PCI was not apparent. Pneumoperitoneum was improved after four weeks with intravenous hyperalimentation. But she presented recurrent severe diarrhea and high fever whenever she tried to take food orally. Klebsiella pneumoniae was proved in her jejunal juice by bacteriologic examination. Intravenous prostaglandin F2 alpha and oral fosfomycin calcium intake made her condition better. Benign pneumoperitoneum without PCI is rarely reported in the patients with SSc. In her condition, weakness of intestinal wall, hypomotility of intestine, unusual bacterial overgrowth, and elevated intraluminal pressure made intraluminal gas go through the wall of the fragile intestine of SSc. As operation of intestine of SSc usually cause miserable outcome, pneumoperitoneum accompanied with SSc even if PCI is apparent or not must be treated with conventional manner while there is no signs of peritoneal irritation.

Adult↗

[An autopsy case of anti-neutrophil cytoplasmic antibodies associated vasculitis accompanied by autoimmune hepatitis and hepatocellular carcinoma].

Here we report an autopsy case with anti-neutrophil antibodies (ANCA) associated vasculitis accompanied by autoimmune hepatitis and hepatocellular carcinoma. A 69-year-old woman was admitted to Tokyo Metropolitan Ohtsuka Hospital in October 1995 because of leg edema. She had presented cough in 1990 and diagnosed as interstitial pneumonia, esophageal varices and liver chirosis. On admission, laboratory data showed mild anemia, hypoproteinemia, and marked gammagloblinemia. IgM-HA antibody, HBs antigen, HBs antibody, HCV antibody and HDV antibody were negative. Anti-nuclear antibody, anticentromere antibody, anti-neutrophil cytoplasmic antibody against myeloperoxidase and cathepsin G (MPO-ANCA and cathepsin G), rheumatoid factor and direct coombs test were positive. Serum level of AFP and CEA were elevated. Ultrasonography and computed tomography of abdomen scowed liver chirosis and tumor in left lobe of liver. The diagnosis of liver chirosis based on autoimmune hepatitis and Interstitial pneumonia was made with clinical course, laboratory findings and radiographic findings although liver biopsy was not performed. She complained of bloody stool due to ulcer of the large intestine, and died of liver failure which progressed rapidly. The autopsy findings detected that pulmonary fibrosis, liver fibrosis with multiple hepatocellular carcinoma, necrotizing crescentic glomerulonephritis, and vasculitis of small artery inn colon. This was the first report of MPO-ANCA associated vasuculitis complicated with autoimmune hepatitis and hepatocellular carcinoma. Clinical significance of ANCA and immunogenetic background of these diseases were discussed.

Aged↗

Enhanced levels of chemiluminescence and platelet activating factor in urease-positive gastric ulcers.

Helicobacter pylori are believed to play an important role in the formation of gastric ulcer in a syndrome characterized by a high urease activity. On the other hand, the production of oxygen radicals and platelet activating factor (PAF) is enhanced in gastric ulcers. The present study is designed to investigate the relationship between the different aspects of gastric mucosal injury, urease activity, oxygen radical production, and PAF content in gastric specimens. Biopsy specimens taken from 35 gastric ulcer patients were studied. Urease activity was detected by a rapid urease test (CLO). Oxygen radical production was measured as a value of luminol-dependent chemiluminescence (ChL) and PAF content was determined by radioimmunoassay in the biopsy samples. The CLO-positive rate was significantly higher in the gastric ulcer group in comparison with that in controls. ChL values and PAF content were significantly increased in gastric ulcers, especially in CLO-positive specimens. The CLO-positive rate, ChL values, and PAF content were also found to be increased at a distant site beyond the ulcer lesions. During the course of macroscopic ulcer healing of CLO-positive cases, the CLO positive level and the ChL values were not significantly decreased, although PAF content was significantly lower. Enhanced oxygen radical and PAF production were observed not only in the ulcer region but also at a distant site from the ulcer in the urease-positive gastric mucosa. The persistent enhancement of ChL values during the healing stage of urease-positive gastric ulcers suggests its involvement in the recurrence of gastric ulcers.

Adult↗

Reversal of altered intestinal mucosal immunity in rats fed elemental diet by supplementation of oleic acid.

We have previously demonstrated that elemental diet (ED) induces decreased lymphocyte transport in intestinal lymph and significant changes in T cell subsets and the number of IgA-containing cells in gut-associated lymphoid tissues of rats. In order to examine whether the low fat content contributes to the induction of immunological changes in gut-associated lymphoid tissues, the effects of additional fatty acid in the ED were investigated. Rats were divided into four groups: elemental diet alone, elemental diet supplemented with 5% oleic acid (OA), elemental diet with 10% OA and conventional diet as a control. These diets were given at the same daily calorie intake for 4 weeks. The flow rate of intestinal lymph showed no significant difference between the four groups. However, lymphocyte flux as well as the percentage of CD3+ and CD4+ cells were significantly greater in the control and the 10% OA groups than in the ED and 5% OA groups. Intestinal lymph showed decreased concentrations of IgG and IgA in the ED group, whereas the addition of 10% OA significantly attenuated the decrease in these levels. In mesenteric lymph nodes, the CD4+/CD8+ ratio was significantly decreased in the ED group, but 10% OA reversed this change. Immunohistochemical analysis of the ileal mucosa showed that in the ED group the population of CD4+ cells was decreased, while the number of CD8+ cells was increased. Supplementation of OA to ED produced similar stepwise attenuation of the changes in lymphocyte subpopulations in the lamina propria, while the 10% OA group reached levels that were not statistically different from controls. In the elemental diet group, there was a significant decrease in immunoglobulin-containing cells of the IgA class in the lamina propria of the intestine. Similarly, the addition of OA induced dose-dependent recovery in the number of IgA-containing cells. These results suggest that a low dietary concentration of fat may be closely related to changes in lymphocyte transport in intestinal lymph and mucosal immunity of intestinal mucosa induced by the feeding of a long-term ED.

Animals↗

Conjugated bile salts regulate turnover of rat intestinal brush border membrane hydrolases.

The mechanisms whereby the conjugated bile salts regulate the activities of the brush border membrane hydrolases and its physiological significance were investigated in rat small intestine, and comparisons were made with the action of pancreatic protease. Rat brush border membrane proteins were metabolically labeled with [35S]methionine, and isolated brush border membrane was incubated with taurocholate or pancreatic elastase. The activity of solubilized hydrolases was assayed and the molecular forms of the hydrolases were examined by SDS-PAGE. The activity and protein bands of alkaline phosphatase and sucrase-isomaltase were solubilized by taurocholate, while alkaline phosphatase was not solubilized by elastase. Solubilized sucrase-isomaltase molecules were proteolytically degraded by elastase, whereas the intact molecule of sucrase-isomaltase was solubilized by taurocholate. Next the physiological role of bile salts in brush border membrane hydrolase turnover were investigated using metabolic labeling of brush border membrane hydrolase and immunoprecipitation in biliary diversion rats. After three days of biliary diversion, a significant increase in alkaline phosphatase activity was observed. Although synthesis of alkaline phosphatase in biliary diversion rats was similar to that observed in control rats, biliary diversion rats showed 1.5-fold slower turnover of alkaline phosphatase when compared with control rats. These results suggest that conjugated bile salts in the intestinal lumen may cause a rapid turnover of brush border membrane hydrolases, which may be increased by the enhanced enzyme degradation. The mechanisms for the enhanced degradation appeared to be solubilization of hydrolases caused by the detergent activity of bile salts. Therefore, conjugated bile salts may play an important physiological role in the regulation of expression of the protease-resistant enzymes such as alkaline phosphatase.

Alkaline Phosphatase↗

Intravital demonstration of sequential migration process of lymphocyte subpopulations in rat Peyer's patches.

BACKGROUND & AIMS: Although recirculation of lymphocytes through Peyer's patches is important for specific immune defense, the intraorgan migration of lymphocyte subpopulations has not been clearly understood. The aim of this study was to compare the spatial distributions of labeled lymphocytes among various subpopulations in rat Peyer's patches. METHODS: Lymphocytes collected from intestinal lymph were separated into CD4+, CD8+, and T and B cells, labeled with a fluorochrome carboxyfluorescein diacetate succinimidyl ester, and injected into the jugular vein. Peyer's patches of recipient rats were observed by intravital fluorescence microscopy. RESULTS: No significant difference was found in the percentage of lymphocytes in transit or in the rolling velocity among different subpopulations. Lymphocytes sticking to the venules increased in number at 10-20 minutes, with preferential adherence of CD4+ cells to venules of 25-50 microns and preferential adherence of B cells to the venules of a wider size range. After 30 minutes, extravasated lymphocytes moved into the interstitium. B cells migrated from venules more quickly than CD4+ cells. CD8+ cells showed an intermediate pattern between CD4+ and B cells in sticking and migratory behaviors. Subsequently, CD4+ and CD8 cells preferentially appeared in parafollicular microlymphatics. CONCLUSIONS: Significant differences were observed among lymphocyte subpopulations in terms of spatial distribution of lymphocytes sticking to venules, migration into the interstitium, and their lymphatic transport.

Animals↗

In vivo effect of chronic administration of vasoactive intestinal peptide on gut-associated lymphoid tissues in rats.

The in vivo effects of chronic administration of vasoactive intestinal peptides (VIP) on the lymphoid cell traffic and the population and function of cells in intestinal lymph and gut-associated lymphoid tissues were examined in rats. VIP was continuously infused from the superior mesenteric artery in rats at a dose of 10 ng/min/kg body weight for 96 h. Lymphocyte transport through intestinal lymph was significantly reduced by VIP without any changes in lymph flow. When lymphocyte subpopulation was examined in intestinal lymph, T cell subsets were decreased with a dominant reduction in the population of helper T cells. T cell subsets were also decreased in mesenteric lymph nodes, but in this case suppressor/cytotoxic T cell subsets were mainly reduced. Despite of the decrease in lymphocyte transport through intestinal lymph and changes of lymphocyte subpopulation, proliferative response of lymphocytes from intestinal lymph and mesenteric lymph nodes to phytohemagglutinin did not show any significant alteration after administration of VIP. By histochemical study on the lamina propria of the small intestine, the population of pan T cells, especially helper T cells, was demonstrated to be significantly decreased after VIP treatment. There was also a marked decrease in the number of immunoglobulin (Ig) A-containing cells in the lamina propria of the small intestine in VIP-treated rats, while no significant changes were seen in the number of IgG and IgM-containing cells. Our present results showed the possibility that a long-term alteration of serum VIP levels could affect the dynamics of immune effector cells and IgA production in gut-associated lymphoid tissues.

Animals↗

Influence of fatty acid absorption on bidirectional release of immunoglobulin A into intestinal lumen and intestinal lymph in rats.

Effects of absorption of long and middle chain fatty acids on IgA secretion into the intestinal lumen and intestinal lymph and the factors which evoke changes in IgA secretion during the absorptive process were examined in rat small intestine. Bidirectional secretion of IgA from the intestinal mucosa into the intestinal lumen and intestinal lymph was continuously observed in the control condition. Perfusion of oleic acid (a long-chain fatty acid) micelle into the jejunal loop induced a significant increase in IgA output into the intestinal lymph. In contrast, lymphatic output of IgA was significantly decreased when oleic acid micelle was administered intraduodenally. Absorption of octanoic acid, a middle-chain fatty acid, did not produce any significant changes in IgA output into either direction. CR1505, a CCK-receptor antagonist, significantly attenuated the oleic acid-induced increase in IgA secretion into the intestinal lumen, but did not affect the oleic acid-induced decrease in lymphatic IgA secretion. Pluronic L-81, an inhibitor of chylomicron formation and secretion, significantly attenuated the decrease in IgA output into the intestinal lymph during oleic acid absorption without affecting the luminal IgA output. The rate of release of IgA into the intestinal lumen is stimulated by absorption of long-chain fatty acids possibly through the influence of locally released CCK, while the transport process of IgA into lymphatics is controlled by a different mechanism which is closely correlated with the intracellular formation and secretion of chylomicron.

Animals↗

Attenuation of endotoxin-induced intestinal microcirculatory damage by eicosapentanoic acid.

The major objective of this study is to investigate whether oral administration of eicosapentanoic acid (EPA) has any preventive effect on endotoxin-induced microcirculatory damage of rat small intestine. EPA in a daily dose of 300 mg/kg was orally given to male Wistar rats for 3 wk. Submucosal microvessels of the ileum were observed by intravital microscopy equipped with a high-speed video camera system after the intra-arterial infusion of endotoxin at a dose of 2 mg.kg-1.h-1. The number of sticking leukocytes was significantly increased at 30 min after the treatment of endotoxin especially along the smaller branch of intestinal venules. It reached the maximal plateau at 45 min after treatment. The pretreatment of EPA significantly attenuated the increase in sticking leukocytes induced by endotoxin. A platelet-activating factor (PAF) antagonist 2-[N-acetyl-N-(2-methoxy-3-octadecylcarbamoyloxy propoxycarbonyl) aminomethyl]-1-ethylpyridinium chloride (CV-6209) significantly prevented the increased leukocyte sticking to the same extent as EPA treatment. Thirty minutes after endotoxin infusion, red blood cell (RBC) velocity was significantly decreased in both arterioles and venules. RBC velocity appeared to be continuously decreased thereafter and reached its minimum value at approximately 60 min. EPA treatment was revealed to prevent the decrease in RBC velocity of microvessels induced by endotoxin. CV-6209 also significantly attenuated the decreased RBC velocity. The remarkable elevation of PAF content in the ileal mucosa as observed by endotoxin infusion was also significantly attenuated by administration of EPA.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

Increased proliferative response of lymphocytes from intestinal lymph during long chain fatty acid absorption.

The effect of long chain and medium chain fatty acid absorption on transport and mitogen-induced blast transformation of lymphocytes in intestinal lymphatics was investigated. Intestinal lymph was collected from mesenteric lymph duct cannulated rats maintained in Bollman's cage. Following the intraduodenal administration of oleic acid (long chain fatty acid) or octanoic acid (medium chain fatty acid), only oleic acid produced a significant increase in lymphocyte flux and enhanced proliferative response of lymphocyte in intestinal lymph, without significant alteration of lymphocyte subsets. These changes appeared to be closely correlated with the appearance of radiolabelled oleic acid. Absorption of a medium chain fatty acid, octanoic acid, most of which appeared to be transported to portal blood, did not produce a significant elevation of lymphocyte flux or increased proliferative response of lymphocyte in intestinal lymph. Pluronic L-81, which is a potent inhibitor of the intracellular formation and secretion of chylomicron, significantly attenuated the increased lymphocyte flux and suppressed the enhancement of lymphocyte responsiveness to PHA in intestinal lymph after stimulation by oleic acid administration. There is a possibility that lymphocyte transport and proliferative response in intestinal lymph during oleic acid absorption are closely related to the process of chylomicron formation and secretion to lymphatics in the intestinal mucosa.

Animals↗

Changes in intestinal absorption of nutrients and brush border glycoproteins after total parenteral nutrition in rats.

The effect of total parenteral nutrition on nutrients absorption and glycoprotein changes of brush border membrane was examined in rat small intestine. In total parenteral nutrition rats, a marked decrease in activity of brush border enzymes was observed mainly in the proximal and middle segments of the intestine. Galactose perfusion of jejunal segment showed that hexose absorption was significantly inhibited, while intestinal absorption of glycine or dipeptide, glycylglycine was not significantly affected by total parenteral nutrition treatment. When brush border membrane glycoprotein profile was examined by [3H]-glucosamine or [3H]-fucose incorporation into jejunal loops, significant changes were observed in the glycoprotein pattern of brush border membrane especially in the high molecular weight range over 120 kDa after total parenteral nutrition treatment, suggesting strong dependency of glycoprotein synthesis on luminal substances. Molecular weight of sucrase isomaltase in brush border membrane detected by specific antibody showed no significant difference, however, in total parenteral nutrition and control rats. Also, molecular weight of specific sodium glucose cotransporter of intestinal brush border membrane detected by selective photoaffinity labelling was not altered in total parenteral nutrition rats. It may be that prolonged absence of oral food intake may produce significant biochemical changes in brush border membrane glycoprotein and absorptive capacity of small intestine, but these changes were not observed in all brush border membrane glycoproteins.

Animals↗