Biomedical subjects

T Shimoyama

Publications and source records attributed to T Shimoyama.

At least 109 records · Page 6Linked to original sources

PubMed1999

Intraosseous squamous cell carcinoma arising in association with a squamous odontogenic tumour of the mandible.

We report a rare occurrence of intraosseous squamous cell carcinoma (SCC) arising in association with a squamous odontogenic tumour (SOT), which had not previously been documented in the literature. A 53-year-old man had, for 5 years, a well-demarcated radiolucency attached to the impacted third molar of the mandible. The enucleated specimen had a characteristic pattern of SOT, but in which a few epithelial islands showed atypical features suggestive of SCC. Intense p53-, proliferating cell nuclear antigen- and Ki-67-positive cells were detected in carcinoma areas. Within 2 months, aggressive bone destruction showing typical findings of intraosseous SCC appeared. The present tumour is presumably a malignant variant of SOT.

Ameloblastoma↗

PubMed1999

In vitro comparison study of CD63 and CD62P expression after contacting leukocyte filters.

CD63 and CD62P have been recognized as platelet activation markers. This study investigated the secretion of these antigens to compare the platelet activation between a newly developed stainless steel leukocyte filter (SSLF) and 7 polyester or polyurethane commercially available leukocyte filters. Flow cytometry demonstrated that the SSLF initiated significantly smaller effects in terms of mean fluorescence intensity of CD63 (p<0.03) and of the amount of CD62P expressing platelets (p<0.002) compared to the polyurethane filters. However, there was no statistical difference between the SSLF and polyester filters. The result of this study suggests that the SSLF caused less platelet activation than the polyurethane filters and has biocompatible characteristics comparable to the currently available polyester filters. Stainless steel was selected because of its physicochemical conductivity. With these results, further evaluation of the SSLF will be continued in an attempt to develop an active immunomodulator using this unique characteristic.

Adult↗

PubMed1999

Preliminary evaluation study of a prototype hollow fiber membrane for the continuous membrane autotransfusion system.

A totally new autotransfusion system has been developed utilizing a hollow fiber membrane, based upon plasmapheresis technology. Prior to fabricating the system, it was essential to evaluate the basic performance characteristics of the filter, which was designed particularly for the new system. The objective of this study was to prove or disprove that such a system would be available using this filter. An in vitro study was conducted on the filter using bovine blood. The result of the study showed that the filter could process 2-20% of hematocrit blood at a flow rate greater than 250 ml/min of inlet blood continuously. Moreover, it could concentrate 5-20% hematocrit blood to hematocrit percentages greater than 40% by a single passage through the filter. These results seemed to prove that a rapid, continuous, and compact autotransfusion system could be developed using this filter.

Blood Transfusion, Autologous↗

PubMed1999

Most gastric cancer occurs on the distal side of the endoscopic atrophic border.

BACKGROUND: The endoscopic atrophic border indicates the extent of atrophic gastritis. The aims of this study were to examine the relation of intestinal and diffuse types of gastric cancer to the atrophic border and to study the pathologic condition of the atrophic border. METHODS: In 83 patients with gastric cancer the extent of atrophic gastritis was assessed macroscopically. In 46 patients gastric biopsy specimens were also taken, to compare the histologic features of gastritis proximal and distal to the atrophic border. RESULTS: Eighty-five per cent of gastric cancers (including 93% of intestinal type) occurred on the distal side of the atrophic border. Early diffuse gastric cancer arose closer to the atrophic border than intestinal-type cancer and was more likely to be sited proximal to it. Histologically, the grade of polymorphonuclear cell infiltration (inflammatory activity) and Helicobacter pylori density were significantly greater on the proximal side (P < 0.05), whereas the grades of glandular atrophy and intestinal metaplasia were significantly greater distally (P < 0.001). CONCLUSIONS: The atrophic border delineates the area of atrophic gastritis and intestinal metaplasia, and it is within the distal part of the stomach that gastric cancer occurs most frequently. Endoscopists should observe the distal side particularly carefully to identify early gastric cancer. The relationship of the two histologic types of cancer to areas of intestinal metaplasia and 'active' inflammation may have implications for the pathogenesis of cancer and, if so, for the potential protective effect of H. pylori eradication.

Endoscopy, Gastrointestinal↗

PubMed1999

Serum levels of thyroid-stimulating hormone receptor antibodies during IFN-alpha2a treatment of chronic hepatitis C.

Twenty chronic hepatitis C patients with baseline levels of thyroid hormones, antithyroglobulin, and antimicrosomal antibodies within the normal range were monitored by thyroid testing during a 26-week treatment with interferon-alpha2a (IFN-alpha2a). The present study was aimed at retrospectively analyzing thyroid-stimulating hormone (TSH) receptor antibodies, employing stored serum samples obtained from these patients at baseline, at 12 weeks, and at the end of IFN-alpha2a treatment. Ten patients (group A) received IFN-alpha2a at a total dose of 474 million units (MU), and 10 patients (group B) at a total dose of 774 MU. None of the patients produced antithyroglobulin and antimicrosomal antibodies. Two patients in group A exhibited elevated TSH levels without free thyroid hormone alterations while on the treatment. At baseline, 1 patient in group A had a positive TSH binding inhibitory immunoglobulin, and 1 patient in group B was positive for thyroid-stimulating antibody at the end of treatment. Both patients remained euthyroid throughout the treatment. Treatment with IFN-alpha2a may infrequently induce the production of TSH receptor antibodies in chronic hepatitis C patients provided preexisting autoimmune thyroid disease is precluded.

Adult↗

PubMed1999

Characterization of a cb-type cytochrome c oxidase from Helicobacter pylori.

Helicobacter pylori is a microaerophilic Gram-negative spiral bacterium residing in human stomach. A cb-type cytochrome c oxidase that terminates the respiratory chain was purified to near homogeneity by solubilizing the membranes with Triton X-100 and applying anion exchange, Cu-chelating, and gel filtration chromatographies. Redox- and CO-difference spectra and pyridine ferrohaemochrome analysis showed the enzyme to contain three haems C, one low-spin protohaem, and one high-spin protohaem that probably forms a dioxygen-reducing bimetalic center with a copper atom. The enzyme actively oxidizes soluble cytochrome c from this bacterium (TNmax of about 250 s-1) with a Km of 0.9 microM. Yeast cytochrome c and N,N,N',N'-tetramethyl p-phenylenediamine (TMPD) are also oxidized at similar maximal velocities with larger Km's. Oxygen pulse experiments on resting cells in the presence of ascorbate plus TMPD or L-lactate indicated that this sole terminal oxidase pumps H+, although the H+ pumping activity by proteoliposomes reconstituted from the enzyme and P-lipids was low. Two main bands with haem C at 58 and 26 kDa were observed upon polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate and succeeding protein and haem staining. Sequencing of the operon encoding the subunits of the enzyme revealed the presence of ccoNOQP. N-terminal analysis of the 58 kDa band showed 15 or 13 amino acids coinciding with the amino acid sequences deduced from the DNA of ccoN and ccoO. CcoN, the largest subunit bearing two protohaems and copper, and ccoO, a mono-haem cytochrome subunit form a protein complex with an apparent molecular mass of 58 kDa, even in the presence of sodium dodecyl sulfate. The 26 kDa band is tentatively assumed to be ccoP with two haems C.

Amino Acid Sequence↗

PubMed1999

VacA seropositivity is not associated with the development of gastric cancer in a Japanese population.

OBJECTIVES: Infection with Helicobacter pylori strains producing vacuolating cytotoxin (VacA) is associated with enhanced gastric mucosal damage and the development of gastric mucosal atrophy. The aim of this study was to investigate whether VacA seropositivity is associated with increasing risk of gastric cancer in Japanese populations which have much higher incidence of gastric cancer than Western populations. METHODS: Serum sample was collected from 81 patients with gastric cancer and 81 sex- and age-matched endoscopically evaluated control subjects. Histologically, 62 cancers were of the intestinal type and 76 were early gastric cancer. H. pylori and VacA IgG antibodies were assayed by Western blotting using Chiron Diagnostics' Recombinant Immunoblot Assay (RIBAa). RESULTS: VacA seropositivity was 68% (55/81) in patients with gastric cancer and 70% (57/81) in controls. The odds ratio for the risk of gastric cancer in VacA seropositives was 0.89 (95% CI 0.46-1.74). In H. pylori seropositive patients and their control subjects (matched H. pylori-positive controls), VacA seropositivity was the same 80.6% (50/62). The odds ratio for the risk of gastric cancer in H. pylori-positive patients if VacA seropositive was 1.00 (95% CI 0.41-2.44). The mean relative intensity of VacA antibody titre was 3.01+/-0.18 in the 55 VacA seropositive cancer patients and 3.09+/-0.17 in the 57 VacA seropositive control subjects (difference not significant). CONCLUSION: These results suggest that VacA seropositivity is not associated with increasing risk of gastric cancer in Japanese populations.

Antibodies, Bacterial↗

PubMed1999

Collagenous fibroma (desmoplastic fibroblastoma) presenting as a parotid mass.

We describe the case of a 50-year-old man who was found to have a painless, slow-growing parotid mass of 10 months duration. At surgery, a well-delimited, lobulated 4x5-cm tumor was located on the deep lobe of the left parotid gland, adhering to the parotid sheath and masseteric fascia. Follow-up 6 years later has shown no evidence of recurrence. Cardinal morphologic features included multiple nodules of sparsely distributed stellate-or spindle-shaped fibroblasts within a collagenous or myxocollagenous stroma. Fascial involvement and entrapment of salivary gland were focally identified at the edges. Tumor cells were diffusely positive for vimentin with faint focal staining for alpha-smooth muscle actin. These findings satisfied the diagnostic criteria for collagenous fibroma (desmoplastic fibroblastoma). Ours represents the first report of this tumor type mimicking a parotid tumor.

Fibroma, Desmoplastic↗

PubMed1999

Primary intraosseous carcinoma of the mandible with probable origin from reduced enamel epithelium.

This report describes a case of primary intraosseous carcinoma (PIOC) arising de novo in the mandible. The patient was a 74-year-old woman and an early PIOC was found incidentally during histopathological examination of the pericoronal tissue obtained at extraction of a deeply impacted third molar. The curetted soft tissues consisted of a microinvasive, keratinizing squamous cell carcinoma with scattered foci of carcinoma cells showing calcification; stromal osseous metaplasia was also observed. After additional treatment, the patient has remained free of disease for 2 years. Since the tumor was completely enclosed in the bone, the only identifiable source of the present PIOC is the reduced enamel epithelium. Despite its rarity, this case emphasizes the importance of careful histologic examination of all apparently innocuous dental follicles that are removed surgically.

Aged↗

PubMed1999

[Resuscitation from the viable but nonculturable state of Helicobacter pylori].

It is well known that the change of state from the culturable to not culturable on pathogenic organisms could easily occurred. These states of bacteria were so called viable but nonculturable (VNC). The coccoid form of H. pylori is seems to be in this state. The possibility of resuscitation of H. pylori was examined in vitro. The coccoid form bacteria was treated with Ammonium Sulfate and heat shock before culture, and cultured in Brucella broth containing, sodium pyruvate, laked human erythrocyte and serum. The growth of the rod spiral form was found in the coccoid form bacteria, and further the bacteria could grow on blood agar and Skirrow agar as well as the original strain. It was strongly suggested that the resuscitation from VNC state of cells to culturable form consists of two processes, stimulation and supplemented of appropriate nutrition.

Bacteriological Techniques↗

PubMed1999

Increased expression of IL-10 and IL-12 (p40) mRNA in Helicobacter pylori infected gastric mucosa: relation to bacterial cag status and peptic ulceration.

AIMS: To investigate interleukin (IL)-12 (p40) and IL-10 mRNA expression levels in the gastric mucosa in relation to H pylori cag status, peptic ulceration, and histopathology. METHODS: In 81 dyspeptic patients, antral and corpus biopsies were taken for reverse transcriptase polymerase chain reaction (RT-PCR) and histology. G3PDH (control) and IL-10 and IL-12 were coamplified in a duplex PCR and the ratios of cytokines to G3PDH were determined. Bacterial ureA and cagA status was determined by RT-PCR. RESULTS: IL-10 mRNA expression in both the antral and corpus mucosa was greater (p < 0.01) in cagA positive infection than in H pylori negative patients with histologically normal mucosa. No increase in IL-10 mRNA expression was observed in cagA negative infection. Both in the antral and corpus mucosa, IL-12 mRNA expression was greater (p < 0.05) in cagA positive than in cagA negative infection and uninfected patients with normal gastric mucosa. In cagA positive infection, there was a correlation between IL-10 and IL-12 mRNA expression in both the antral mucosa (r = 0.515, p < 0.01) and the corpus mucosa (r = 0.6, p < 0.005). IL-12 mRNA expression in the antral mucosa was significantly more frequent in H pylori positive patients with duodenal ulcer than in those with gastric ulcer or nonulcer dyspepsia. No difference was observed in IL-10 mRNA expression in relation to endoscopic diagnosis. CONCLUSIONS: CagA positive H pylori infection is associated with increased IL-10 and IL-12 mRNA expression. The increased expression of IL-12 mRNA in the majority of patients with duodenal ulcer suggests that Th1 responses may predominate and play a role in the pathogenesis of duodenal ulceration.

Adolescent↗

PubMed1999

Effect of leukocytapheresis therapy using a leukocyte removal filter in Crohn's disease.

Eighteen patients with active Crohn's disease were treated with one leukocytapheresis session per week for a five-week intensive therapy, decreasing to one leukocytapheresis session per month for five sessions of initial maintenance therapy. Nutritional indices, inflammatory reactions, flow cytometry profiles, and cytokine production were also assessed before and after the intensive and initial maintenance therapy. Nine of the patients (50%) attained remission at the end of the intensive therapy. The nine non-remission patients had exhibited longer periods of suffering and more severely affected sites prior to the therapy. In 14 of 18 patients (77.8%), the nutritional indices, Internal Organization of Inflammatory Bowel Disease (IOIBD) score and Crohn's Disease Activity Index (CDAI) improved from the pretherapy levels, but only the remission group (50%) showed improvement in C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR). The remission group showed significantly higher pretherapy CD4+ CD45+ cell ratios and interleukin-2 (IL-2) production than the non-remission group, and significantly lower activated cells.

Adult↗

PubMed1999

[Mechanism of leukocytapheresis effect in the treatment of ulcerative colitis].

To solve adverse effects of high dose steroid administration for patients with moderately severe and severe ulcerative colitis (UC), additional use of leukocytapheresis (LCAP) was tried to settle colonic inflammation. We evaluated immunological changes in the treatment of LCAP using leukocyte removal filter for UC patients. We then assessed the clinical effectiveness of LCAP compared with that of high dose of steroid therapy. LCAP removed monocytes, granulocytes, and lymphocytes presenting CD 11 b+, CD 11 c+, and HLADR+, selectively from the patients. Proinflammatory cytokine productions measured such as TNF alpha, IL-1 beta, and IL 8 reduced and IL 10 increased immediately after LCAP compared with before perfusion. Improved rate was about 70% for LCAP group and about 40% for high dose steroid group (Refer J Gastroenterol). Selective removal of granulocyte, monocytes, and activated lymphocytes inhibits proinflammatory cytokine production and increases immune modulating cytokine productions (Refer Therapeutic Apheresis). Then quick inhibition of several inflammatory deteriorated factors simultaneously controls the activity and clinical symptoms of UC with less severe adverse effects. It can be considered one option for treatment of UC.

Adult↗

PubMed1999

A case of an electrical burn in the oral cavity of an adult.

Electrical burns in the oral cavity account for 2.2% of all electrical burns and only 0.12% of all burns; thus, the incidence of electrical burns in the oral cavity is relatively low. As this type of injury occurs in the oral cavity when an individual sucks or chews on a live electrical wire, extension cord, plug, or outlet, most cases occur in toddlers or preschool children, and adult cases are extremely rare. Here we describe a case of an electrical burn in a 56-year-old man who accidentally bit the electric wire of a cleaner while carrying out repairs. Conservative treatment, without surgery, was performed. Two years after the injury, a slight scar and a small tongue deformity remain, but no functional disturbance has been observed.

Burns, Electric↗

PubMed1999

So-called simple bone cyst of the jaw: a family of pseudocysts of diverse nature and etiology.

The nature and etiology of so-called simple bone cyst (SBC) are still a subject of debate. Our comprehensive review of the literature suggests that SBC, which appears histologically to be a single entity, has different natures and etiologies, resulting in divergent clinical features. In addition, an interesting case of mandibular SBC in an 11-year-old girl is presented with details of radiographic changes over a 7-year period. Fully documented patient records revealed that this lesion originated in the apical area of the first molar and took about 4 years to develop into a clinically evident bony expansion.

Child, Preschool↗

PubMed1999

[Epidemiological study for infection with H. pylori in Japan compared with that in USA, Europe and Asian Pacific area].

The prevalence of infection with H. pylori in developed countries was about 20%, on the other hand in developing countries it reached over 80%. In developed countries 40% of infants already had anti-H. pylori antibody and the prevalence of infection rapidly increased and then reached the peak (80%) in teenager. In contrast in developed countries the rate of infection with H. pylori was below 20% in teenager and gradually increased by age (1% per 1 year). In our country an unique pattern of the prevalence of infection with H. pylori was observed. The rate of infection with H. pylori in young person was low and increased with 1% per 1 year (developed countries pattern). However, middle-aged person had higher rate of infection of H. pylori (over 85%) (developing countries pattern). These results suggested H. pylori infection would be closely associated with childhood living conditions than current living (including socioeconomic) status. From this point of view, the prevention for infection with H. pylori in childhood will be most important to prevent the gastroduodenal disease related with H. pylori in the future.

Adolescent↗

PubMed1999

[History of the treatment of Helicobacter pylori and clinical efficacy].

The combination of a proton pump inhibitor with antibiotics has been accepted as an effective treatment for the eradication of Helicobacter pylori and the most rational regimen to cure peptic ulcers. Triple therapies including two antibiotics and a proton pump inhibitor achieves constant and high eradication rate. The one-week, low-dose triple regimen including metronidazole has been accepted in European countries, but the new triple therapy with proton pump inhibitor, amoxicillin and clarithromycin is recommended for treatment of H. pylori infection in Japan. Quadruple therapy with two antibiotics, bismuth and a proton pump inhibitor is a second-line therapy. Triple therapy with ranitidine bismuth and two antibiotics may be promising.

Anti-Bacterial Agents↗

PubMed1999

[Successful lithium carbonate therapy for a patient with intractable and severe aplastic anemia].

A 16-year-old female patient who had been given a diagnosis of severe aplastic anemia underwent 2 courses of a combined regimen of corticosteroid pulse therapy and androgen therapy. This proved ineffective. Antilymphocyte globulin therapy was also ineffective. The patient was then given lithium carbonate at a dose of 600 mg/day in combination with an androgen derivative. This had a dramatic effect on her peripheral blood smear. Within 3 weeks after the first course of this treatment, she no longer required red blood cell transfusions. Also, once the lithium carbonate dose was increased to 1,200 mg/day, the patient no longer needed exogenous platelet transfusions. Approximately 6 months after the start of combination therapy, a peripheral blood smear showed entirely normal results. However, 2 months after lithium carbonate was discontinued probably as a result of drug-induced liver dysfunction, both leukocytopenia and thrombocytopenia reappeared. Therefore, lithium carbonate was readministered at a dose of 400 mg/day, and later at a dose of 800 mg/day. Again, the patient showed improvements in 3 blood components without any adverse effects. We concluded that lithium therapy was remarkably useful for this patient with intractable and severe aplastic anemia.

Adolescent↗