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Biomedical subjects

Y Yamashiro

Publications and source records attributed to Y Yamashiro.

At least 91 records · Page 5Linked to original sources
PubMed1998

Chronic oral antigen exposure induces lymphocyte migration in anaphylactic mouse intestine.

Persistent diarrhea, vomiting, and dehydration are symptoms often seen in patients suffering from food allergy after chronic antigen exposure; however, the precise mechanisms involved have not been well defined. In an effort to clarify the mechanisms of the chronic intestinal changes attributable to genuine IgE-mediated anaphylactic reactions induced by orally administered antigen, a mouse model was established by s.c. implantation of a murine hybridoma capable of producing monoclonal anti-trinitrophenyl IgE antibody, and the morphologic and immunologic changes occurring in the intestine upon chronic antigen exposure were investigated. In the early stage after ingestion of the antigen, diarrhea and noticeable infiltration of mast cells as well as eosinophils into the lamina propria were observed. A substantial increase in serum histamine levels as well as an increase in leukotriene C4 synthesis in the jejunal mucosa were observed 1 h after antigen challenge. Also, the synthesis of leukotriene B4 was significantly elevated for up to 9 h after antigen challenge. The expression of both intercellular adhesion molecule-1 (ICAM-1) on mucosal vascular endothelial cells and IAd on epithelial cells was markedly enhanced, and noticeable infiltration of eosinophils and lymphocytes was also confirmed in the mouse model after chronic antigen exposure. These findings suggest that oral antigen exposure induces anaphylactic reactions in the intestine mediated by mast cells and eosinophils in response to the IgE-antigen complex in the early phase, and also induces lymphocyte migration after chronic antigen exposure.

Administration, Oral↗
PubMed1998

[Total collapse of the right lung in a patient with allergic bronchopulmonary aspergillosis].

A 29-year-old man was admitted to the hospital because of a high fever and dyspnea. He had a history of bronchial asthma and had had a bullectomy of the right lung at 15 years of age. He had visited a family physician because of fever and non productive coughing. Medications had no effect on his symptoms, and dyspnea developed. A chest X-ray film showed total collapse of the right lung, and he was referred to our hospital. Laboratory data showed eosinophilia and a high titer of IgE. Total obstruction of the right main stem bronchus by mucous plug was found during fiberoptic bronchoscopy. Aspergillus was detected by pathological examination of bronchial lavage fluid. Tests for aspergillus-specific IgE and IgG antibody were positive, as was immediate skin reactivity to Aspergillus. Allergic bronchopulmonary aspergillosis (ABPA) was diagnosed. Infusion and inhalation of a corticosteroid and fluconazole were effective; the symptoms resolved and X-ray findings improved. While migratory infiltration, proximal bronchiectasis and segmental or subsegmental atelectasis caused by a mucous plug are common X-ray findings in allergic bronchopulmonary aspergillosis, total collapse is rare.

Administration, Inhalation↗
PubMed1997

A case of infantile Dubin-Johnson syndrome with high CT attenuation in the liver.

We report a case of Dubin-Johnson syndrome (DJS) with severe infantile cholestasis and elevated computed tomography (CT) attenuation of the liver. Increased levels of urinary coproporphyrin I were found as well as pigment granules in the hepatocytes and hepatosteatosis. The CT attenuation was markedly higher in the liver of this patient at the ages of 3 and 7 months than in the spleen or kidneys. This high attenuation may be a finding specific to infantile DJS and, therefore, abdominal CT may be helpful in the diagnosis.

Biopsy, Needle↗
PubMed1997

Torsion of autotransplanted splenic tissue in Gaucher disease.

A 12-year-old girl who underwent a splenectomy followed by heterotopic splenic autotransplantation for treatment of hypersplenism secondary to Gaucher disease at the age of 3 years presented with acute lower abdominal pain. Radiological investigations were highly suggestive of torsion of the autotransplanted splenic tissue, which was confirmed during subsequent laparotomy. This is the first known report of torsion of autotransplanted splenic tissue.

Child↗
PubMed1997

The estimated incidence of cystic fibrosis in Japan.

BACKGROUND: It is believed that the incidence of cystic fibrosis (CF) among Asiatic races, including the Japanese, is very rare. This epidemiological study was carried out to investigate the incidence of CF in Japan. METHODS: We collected literature describing CF cases among pure Japanese and found 124 cases reported as CF during the 43 years from 1951, when the first case was reported, to 1993. Only 104 cases (57 male and 47 female patients) of 124 cases met our diagnostic criteria. RESULTS: A simple calculation based on the number of reported CF cases and of live births after 1980 suggested that the incidence of CF is about 1 in 350,000 in the Japanese population. Twenty-nine (27.9% of the total) of 30 patients diagnosed in the neonatal period presented symptoms of meconium ileus, an incidence higher than that reported for the white population. CONCLUSIONS: Our study results suggest that the incidence of CF in the Japanese population is even rarer than had been estimated before and that there is a genetic difference between northern European and Japanese populations.

Adolescent↗
PubMed1997

Reducing cell membrane n-6 fatty acids attenuate mucosal damage in food-sensitive enteropathy in mice.

Mucosal damage is commonly observed in food-sensitive enteropathy in infants, and the generation of leukotrienes is involved in the pathogenesis of this enteropathy. Because supplementing n-3 fatty acids is known to modify the production of leukotrienes, we investigated whether a change of dietary fatty acid composition affects leukotriene synthesis and food hypersensitivity reactions in the intestine by using a mouse model of food-sensitive enteropathy. The model was prepared by feeding ovalbumin to BALB/c mice after intraperitoneal injection of cyclophosphamide. Diets were prepared from soybean oil (control), perilla oil, lard, corn oil, and 0.125 volume of corn oil (low fat diet) and given to mice for 4 wk. Villous heights, crypt depths, leukotriene B4 and C4 production in the intestine were measured. Crypt hyperplasia and villous atrophy were severer in the corn oil-fed group than those of control group, whereas mucosal damage in the perilla oil and low fat diet groups was minimal. In the corn oil-fed group, red blood cell membrane levels of n-3 fatty acids were lower than the control, and the synthesis of leukotrienes was highest among all groups. In the perilla oil and low fat diet groups, n-6 fatty acids were lower than those of control group and leukotriene production was significantly suppressed. These results indicate that reducing cell membrane levels of n-6 fatty acids by feeding less n-6 fatty acids or supplementing n-3 fatty acids, is important to suppress leukotriene biosynthesis for prevention from mucosal damage in food-sensitive enteropathy.

Animals↗
PubMed1997

[First example of Hb lepore Washington-Boston trait in a Japanese].

An abnormal hemoglobin (Hb) found in a 63-year-old Japanese woman presenting with asymptomatic chronic microcytic anemia was extensively characterized by the conventional protein chemistry, restriction mapping of the genomic DNA with Bgl II digestion, and direct sequencing of a relevant segment of the mutant non-alpha-globin gene. The results identified a hybrid globin with delta- and beta-like sequences, from position 1 to 87 and from 105 to 146 (C-terminal), respectively. The delta beta fusion gene was produced by deletion of 7.4 kb involving parts of the two closely linked genes. The break point was somewhere within the homologous 58 bps, from codon 88 to IVS-II-7. The same deletion had repeatedly been reported in Hb Lepore Washington-Boston. The expression of a mild (delta beta)(+)-thalassemia trait in the present case completely agreed with previous reports on representative Hb Lepore heterozygotes. The basis for the activity of Hb Lepore gene which is several times higher than the delta-globin gene was discussed.

Asian People↗
PubMed1996

Effect of severe gastroesophageal reflux on sleep stage in patients with aperistaltic esophagus.

Polysomnography and esophageal pH studies were conducted in 13 patients with an aperistaltic esophagus; seven of these had scleroderma and six were patients treated for achalasia. The percentage total time of pH<4.0 when recumbent exceeded 30% for both groups. There was a total of 51 reflux events for both groups. There were 22 reflux events recorded for both groups that were less than 5 min in length and 29 events greater than 5 min. In 26 of 32 (81%) instances, patients either began awake and went to sleep during a reflux event or did not awake during a reflux event. Only six of 32 (19%) reflux events caused sleep disruption. We conclude that even the severe reflux demonstrated in this subset of patients does not always disrupt sleep. Patients may have severe prolonged reflux and not arouse.

Acute Disease↗
PubMed1996

[Diagnosis of legionellosis by microagglutination test--comparison to indirect immunofluorescent antibody method].

We studied the micro-agglutination method (MAT) for the diagnosis of legionellosis. Serum samples were collected from 44 clinically legionellosis suspected patients (17 positive with indirect immunofluorescent antibody technique [IFA] and 27 IFA negatives) and 20 healthy adults (25-30 years old). MAT showed negative results with sera collected from healthy adults and IFA negative patients, 8 out of 17 cass of IFA positive patients showed positive results in MAT. The remaining 9 cases out of 17 were negative in MAT judging from our criteria (1:256 in single serum or fourfold rise to 1:128 in pair sera). MAT had good proportion to IFA in samples collected within three weeks after onset of each disease. All sera that became positive in MAT were sampled within four weeks after onset of each illness. It was noted that MAT was mainly related to IgM-class antibodies. These relationships must be decided by investigating more cases of legionellosis. According to the result of this study, the MAT method was thought to be useful for rapid diagnosis of legionellosis.

Adult↗