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Biomedical subjects

M Asaka

Publications and source records attributed to M Asaka.

At least 145 records · Page 8Linked to original sources
PubMed1998

Monoclonal origin of an esophageal carcinosarcoma producing granulocyte-colony stimulating factor: a case report.

BACKGROUND: Carcinosarcomas are comprised of carcinomatous and sarcomatous elements, and their histogenesis remains unclear. The authors examined the serum concentrations of hematopoietic growth factors and performed immunohistochemical studies on an esophageal carcinosarcoma from a patient with marked granulocytosis to determine its histopathogenesis and clonality. METHODS: The authors examined the case of a 63-year-old man with a polypoid tumor of the esophagus associated with marked leukocytosis (131 x 10(9) per liter). Immunohistochemical staining of the esophageal tumor was performed using monoclonal antibodies against granulocyte-colony stimulating factor (G-CSF), keratin, epithelial membrane antigen (EMA), and vimentin. RESULTS: The patient's leukocyte count was increased (124 x 10(9) per liter) on admission. Because mature granulocytes predominantly were increased despite the absence of apparent infection, the patient's serum G-CSF concentration was examined and found to be 286.0 pg/mL and to increase with time. After thoracic esophagectomy was performed, granulocyte count and serum G-CSF concentration rapidly normalized. G-CSF concentration was 50-fold higher in the tumor tissue extract than in the extract from normal esophageal tissue. Microscopic examination of the resected specimens revealed that the tumor was comprised of squamous cell carcinoma (SCC) and spindle-shaped sarcomatous elements, and transitional features were observed within these two components. Immunohistochemical examination disclosed cells that were positive for keratin and EMA in the carcinomatous element and vimentin positive cells in the sarcomatous element. However, both types of tumor cells were positive for G-CSF. CONCLUSIONS: The presence of G-CSF in both SCC cells and spindle-shaped sarcomatous cells indicated that these two components originated from a single clone.

Carcinosarcoma↗
PubMed1998

Studies of 13C-urea breath test for diagnosis of Helicobacter pylori infection in Japan.

In recent years Helicobacter pylori infection has been implicated in the etiology of a variety of upper gastrointestinal diseases. The aim of this multi-center trial was to search for the cut-off value of the simple 13C-urea breath test (13C-UBT) for diagnosis of H. pylori infection, and to examine the sensitivity and specificity of 13C-UBT for culture, the rapid urease test (CLO test), histology, and serological tests. Two hundred and forty-eight patients participated in this study after giving their informed consent. Endoscopic biopsy specimens were taken from gastric antrum and corpus for culture (190 patients), CLO test (222 patients), and histology (98 patients). A serological test was carried out for all patients. H. pylori infection was established when culture was positive or more than two of the tests, histology, CLO test, and serological test, were positive, and non-infection status was established when the all tests more than two tests were negative. After baseline breath samples were taken, the patients (who had fasted) were given 100mg of 13C-urea in 100ml water while sitting; they washed out the mouth with water. They were then placed in the left lateral decubitus position for 5 min, and additional breath samples were taken 10, 20, 30, 45, and 60 min after urea administration, with patients in the sitting position. One hundred and sixty-five of the 248 patients were infected, 48 were not infected, and H. pylori infection status was not evaluated in 35 by endoscopic and serological tests. Breath samples at 20 min were employed to determine the cut-off value. Using the receiver operating characteristic (ROC) curve, we determined the cut-off value for a positive UBT at 2.5 delta per thousand. The sensitivities of UBT for culture, CLO test, histology, and serological test were 98.4%, 98.6%, 100.0%, and 92.5%, and the specificities were 78.8%, 82.5%, 83.3%, and 87.3%, respectively. The cut-off value of 13C-UBT for the diagnosis of H. pylori infection was 2.5 delta per thousand; this test is a simple and noninvasive method for the diagnosis of this infection and has high sensitivity and specificity.

Adult↗
PubMed1998

Prevalence of mutations in core promoter/precore region in Japanese patients with chronic hepatitis B virus infection.

We examined the frequency and significance of mutations in the core promoter and precore region in 103 Japanese patients with chronic hepatitis B virus (HBV) infection. HBV DNAs from the patients' sera were amplified by polymerase chain reaction and were directly sequenced. A double mutation (T1762 A1764) in the core promoter was frequently observed in the patients regardless of HBeAg status except for asymptomatic carriers with HBeAg. Furthermore, a mutation at nucleotide 1753 from T to C or G was frequently found in anti-HBe positive patients and was often accompanied by the double mutation. The A1896 mutation was found in only about one fourth of the patients with anti-HBe. These data suggest that the patients with chronic liver diseases frequently had a double mutation regardless of HBeAg status and a mutation at nucleotide 1753 might be associated with HBeAg-negative chronic hepatitis B virus infection.

Amino Acid Sequence↗
PubMed1998

Bone marrow infarction due to acute graft-versus-host disease in an acute lymphoblastic leukemia patient after unrelated bone marrow transplantation.

We report a case of bone marrow infarction in a 20-year-old woman with acute lymphocytic leukemia (ALL) who underwent unrelated bone marrow transplantation (BMT). Hematopoietic engraftment occurred on day 9 and, thereafter, the patient developed acute dermal and hepatic graft-versus-host disease (GVHD). She also experienced severe arthralgia in her knee joints on day 21. Immunosuppressive therapy with prednisolone (PSL) for acute GVHD was given, and the arthralgia improved rapidly, correlating with the improvement in dermal and hepatic GVHD. Based on the laboratory findings and analysis of magnetic resonance images, she was diagnosed as having bone marrow infarction. The cause of the bone marrow infarction was thought to be acute GVHD-related microangiopathy.

Adult↗
PubMed1998

A modified McMullen's staining for Helicobacter pylori: a high-contrast, visibly prominent method.

BACKGROUND: Many stains can be used for the histological assessment of Helicobacter pylori, but all have defects from the standpoint of sensitivity, convenience, stability, visible prominence and cost. This paper describes a stain which produces satisfactory results on all the above accounts. MATERIALS AND METHODS: Paraffin-embedded sections were dewaxed and treated with 0.2% w/v carbol fuchsin for two min; then 1.0% w/v malachite green was applied for two minutes. RESULTS: This technique stained the bacterial from a deep magenta against a light green background. The characteristic morphology of H. pylori was identified very easily as a stumpy curved rod, and the coccoid forms were also identified. Staining was not specific with mixed samples of bacteria, but it was sufficient to identify H. pylori in the gastric mucosa. CONCLUSION: We have established an easy, stable, convenient, low-cost, and easily recognizable staining method for H. pylori in paraffin-embedded tissue.

Coloring Agents↗
PubMed1998

Safety and efficacy of one-week triple therapy for eradicating Helicobacter pylori in children.

BACKGROUND: Proton pump inhibitor-based eradication therapy of Helicobacter pylori has been widely studied in adults, but there have been only a few reports about this therapy in children. The purpose of this study was to investigate the safety and efficacy of 1-week triple therapy for eradication of H. pylori and ulcer healing in children. PATIENTS AND METHODS: We prospectively studied 15 patients aged 2-17 years (5 with gastric ulcers, 8 with duodenal ulcers, and 2 with nodular gastritis alone). Three patients had H2 blocker-resistant duodenal ulcers. Patients received 0.75 mg/kg of lansoprazole b.i.d., 25 mg/kg of amoxicillin b.i.d., and 10 mg/kg of clarithromycin b.i.d. for 7 days. No additional therapy (including antisecretory drugs) was administered to any patients following eradication therapy. Patients underwent endoscopy to obtain antral biopsies (culture, urease test and histology) and to evaluate the mucosal status, and underwent a 13C-urea breath test before and 4-8 weeks after the completion of a 1-week course of therapy. RESULTS: All patients received the full drug regimen. Endoscopy showed complete healing of ulcers in 12 of 13 patients with peptic ulcer disease (92%). H. pylori was eradicated in 13 of 15 patients (87%). Diarrhea and/or an altered taste sensation occurred in 5 patients (33%). There were no hematological or biochemical abnormalities related to therapy. CONCLUSION: The 1-week triple therapy was safe and effective for eradicating H. pylori. The present study showed that ulcer healing in juveniles is closely associated with eradication of H. pylori, and that no additional therapy is required when H. pylori is eradicated. A shorter course of eradication therapy than 2 weeks may be suitable for children with H. pylori infection.

2-Pyridinylmethylsulfinylbenzimidazoles↗
PubMed1998

Highly sensitive urine-based enzyme-linked immunosorbent assay for detection of antibody to Helicobacter pylori.

BACKGROUND: Enzyme-linked immunosorbent assay (ELISA) has been widely used for detection of Helicobacter pylori (H. pylori), but sample collection is often invasive, complicated, and expensive. Urine samples can be obtained noninvasively and are easier and safer to handle than serum samples. A urine-based ELISA, if found to be accurate, would therefore be a useful alternative to serum-based tests for H. pylori. METHODS: An ELISA method was developed for detection of antibodies to H. pylori in urine. Its sensitivity and specificity were compared with those of three commercially available serum-based ELISA kits and the 13C urea breath test (13C-UBT) using samples from 99 healthy volunteers and 20 patients with gastric disorders. RESULTS: With the assumption that 13C-UBT results are 100% accurate, the sensitivity and specificity of the urinary ELISA were 99% and 100%, respectively, and the accuracy (99%) was superior to those of the three serum ELISAs tested. Immunostaining profiles on Western blot analysis using serum samples were almost identical to those obtained using paired urine samples. CONCLUSIONS: These findings suggest that the differences observed among ELISA test results may be due principally to differences between the profiles of antigen coated on plates for the assays, rather than to differences between antibodies in serum and urine. The urine-based ELISA (URINELISA H. pylori) developed in this study is very accurate and would be useful for screening H. pylori infection as an alternative to serum ELISAs.

Antibodies, Bacterial↗
PubMed1998

The UBiT-100 13CO2 infrared analyzer: comparison between infrared spectrometric analysis and mass spectrometric analysis.

BACKGROUND: Although the 13C-urea breath test is the most accurate noninvasive method for detecting the presence of H. pylori infection, the requirement for an expensive mass spectrometer to analyze breath samples has prevented physicians from providing rapid results near the patient. Recently, a new type of infrared spectrometric analyzer, the UBiT-100, was developed for analyzing 13CO2 in breath. The purpose of this study is to compare results analyzed by the UBiT-100 to those analyzed by the mass spectrometric method. METHODS: Four hundred and fifty-three subjects participated in this study. Breath samples were collected before administration of 100 mg of 13C-urea and at 10, 20, 30, 45 and 60 min after administration. Subjects were asked to hold their breath for 10 sec and then exhale in order to collect breath samples containing more than a 2% concentration of CO2. Samples were then analyzed by both methods. RESULTS: The correlation analysis using values at 20 min after the administration of the study drug (433 points) was excellent with the regression equation of Y = 1.034x - 0.203; r = .996. The results of the UBiT-100 were available in 6 min, making the entire testing procedure less than 30 min. CONCLUSIONS: The UBiT-100 infrared analyzer provides a simple and accurate method of performing the urea breath test while the patient is still in the doctor's office.

Breath Tests↗
PubMed1998

Review article: Long-term Helicobacter pylori infection--from gastritis to gastric cancer.

An analysis carried out in 1994 by the WHO International Agency for Research on Cancer (IARC) resulted in Helicobacter pylori being designated as a Group 1 carcinogen and thus clearly having an association with the development of gastric cancer. In the case of H. pylori, the evaluation was made solely on the basis of epidemiological results. In Japan, in 1993, only 235,000 of the 60 million people with H. pylori had gastric cancer. This represents only 0.4% of the infected population. Each individual reacts in a unique way to H. pylori infection in terms of the inflammatory response. The probability of developing cancer will be determined by environmental factors such as diet, duration of or age at acquisition of H. pylori infection, the virulence of H. pylori strains, and host factors including genetic make-up.

Antibodies, Bacterial↗
PubMed1998

Effect of rebamipide, a novel antiulcer agent, on Helicobacter pylori adhesion to gastric epithelial cells.

Helicobacter pylori is a major etiological agent in gastroduodenal disorders. The adhesion of H. pylori to human gastric epithelial cells is the initial step of H. pylori infection. Inhibition of H. pylori adhesion is thus a therapeutic target in the prevention of H. pylori infection. Experiments were performed to evaluate the effect of rebamipide, a novel antiulcer agent, on H. pylori adhesion to gastric epithelial cells. MKN-28 and MKN-45 cells, derived from human gastric carcinomas, were used as target cells. Ten H. pylori strains isolated from patients with chronic gastritis and gastric ulcer were used in the study. We evaluated the effect of rebamipide on H. pylori adhesion to MKN-28 and MKN-45 cells quantitatively using our previously established enzyme-linked immunosorbent assay. The adhesion of H. pylori to MKN-28 and MKN-45 cells was significantly inhibited by pretreatment of these cells with 100 microg of rebamipide per ml. However, the adhesion was not affected by the pretreatment of H. pylori with rebamipide. On the other hand, the viabilities of H. pylori, MKN-28 cells, and MKN-45 cells were not affected by rebamipide. Our studies suggest that rebamipide inhibits the adhesion of H. pylori to gastric epithelial cells.

Alanine↗
PubMed1998

Analysis of immunoglobulin A antibodies to Helicobacter pylori in serum and gastric juice in relation to mucosal inflammation.

Helicobacter pylori is a major etiologic agent in gastroduodenal disorders. In this study, immunoglobulin A (IgA) antibodies to H. pylori antigens were evaluated in serum and gastric juice specimens obtained from patients with gastritis or peptic ulcers by utilizing antibody capture enzyme-linked immunosorbent assays (ACELISAs). Urease alpha subunit (UA), urease beta subunit (UB), the 66-kDa heat shock protein (HSP), and the 25-kDa protein (25K) were used as antigens for the ACELISAs. The antibody titers of the ACELISAs reflect the ratio of H. pylori-specific IgA to total IgA. The ratio is stable, although the antibody concentration fluctuates in gastric juice. By using ACELISAs it was possible to evaluate quantitatively not only serum IgA antibodies but also gastric juice secretory IgA (S-IgA) antibodies. In both serum IgA and gastric juice S-IgA ACELISAs, the titers of antibody to HSP and 25K were remarkably correlated with the histologic grade of gastritis, whereas those to UA and UB were not strongly correlated with histologic grade. Thus, it is useful for estimating the histologic grade of gastritis to quantify serum IgA and gastric juice S-IgA antibodies to HSP and 25K.

Adolescent↗
PubMed1998

Bone marrow dysplasia with basophilic cells in a patient with angiocentric lymphoma.

We report a 46-year-old man suffering from angiocentric lymphoma of the skin. On admission, he had atypical cells rich in basophilic granules in the bone marrow and peripheral blood, in addition to skin eruptions and bone marrow dysplasia. Immediately after diagnosis, the patient was treated with multidrug combination chemotherapy. At first, the chemotherapy markedly relieved the skin eruption and bone marrow dysplasia, and atypical cells in the bone marrow and peripheral blood disappeared rapidly. However, the disease gradually became resistant to chemotherapy, resulting in a gradual deterioration of the skin eruption and bone marrow dysplasia, and reappearance of atypical cells. The levels of serum cytokines such as interleukin-4 and interleukin-6, and of soluble interleukin-2 receptor correlated well with the disease states. These results suggest that the lymphoma cells directly or indirectly induce the production of these cytokines and that a dysregulated cytokine network, which might be caused by lymphoma cells, induces an increase in atypical cells.

Bone Marrow↗
PubMed1998

Morphological heterogeneity of myeloperoxidase-positive granules in normal circulating neutrophils: an ultrastructural study by cryosection.

Ultrastructural localization of myeloperoxidase (MPO) in the granules of human circulating neutrophils was examined by cryosection. On careful comparison with the morphological characteristics of the granules by conventional transmission electron microscopic study, large MPO-positive granules were divided into five types by immunocryoultramicrotomy using monoclonal antibody. Double staining of MPO and lactoferrin (or lysozyme) was also performed. Lactoferrin was generally detected in MPO-negative granules. Lysozyme immunostaining was present in MPO-positive and -negative granules. These data may suggest different functions among large MPO-positive granules of human circulating neutrophils.

Cryoultramicrotomy↗