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Biomedical subjects

M Mizuno

Publications and source records attributed to M Mizuno.

At least 145 records · Page 8Linked to original sources
PubMed1999

Characterization of cytokine expression in the rectal mucosa of ulcerative colitis: correlation with disease activity.

OBJECTIVE: Mucosal inflammation in ulcerative colitis (UC) is presumed to be regulated by Th2-like cytokines. The aim of this study was to characterize local expression of various cytokines mRNA. METHODS: Total RNA was extracted from rectal biopsy specimens in 61 patients with UC, 18 inflammatory controls, and 16 noninflammatory controls. Reverse-transcription polymerase chain reaction (RT-PCR) was used to determine mRNA expression of interleukin (IL)-2, interferon (IFN)-gamma, IL-4, IL-10, IL-13, and IL-15. RESULTS: Expression of IL-10 was more frequent in UC (75.4%) than in noninflammatory controls (37.5%, p < 0.01). IL-4 was more frequently positive in UC (41%) than in inflammatory controls (5.6%, p < 0.01) and in noninflammatory controls (6.3%, p < 0.01). Positive expressions of IL-4 (66.7% vs 20.6%, p < 0.01) and IL-13 (63.0% vs 29.4%, p < 0.01) were higher in active UC than in inactive UC. The positive rate of IL-2, interferon (IFN)-gamma, and IL-15 expression showed no difference among the groups divided by clinical, endoscopic, and histological grade of inflammation. CONCLUSIONS: These findings suggest that in active UC, IL-4 is pivotal, in combination with other Th2-like cytokines. In contrast, Th1-like cytokines and IL-15 bear no definite relation to local inflammation of UC.

Adolescent↗
PubMed1999

In vivo observation of the ileal microadenoma in familial adenomatous polyposis.

Microadenomas or aberrant crypt foci (ACFs) are regarded as early neoplastic lesions that precede the development of macroscopic adenomas. The aim of this study was to characterize surface features of ileal microadenomas in patients with familial adenomatous polyposis (FAP). Magnifying ileoscopy was performed in 19 patients with FAP. A histologically verified adenomatous tubule, the existence of which was suggested by magnified observation, was regarded as a microadenoma. Magnifying ileoscopy detected microadenoma in five patients. In four of the five cases, the ileal microadenomas were identified as areas with tiny crypt openings or serrated surfaces, which were distinctive of nonneoplastic, diminutive protrusions. Magnifying ileoscopy seems to be useful in the detection of ileal microadenomas.

Adenoma↗
PubMed1999

Antibodies to human gastric epithelial cells and heat shock protein 60 in Helicobacter pylori positive mucosa associated lymphoid tissue lymphoma.

BACKGROUND: Development of gastric mucosa associated lymphoid tissue (MALT) lymphoma is thought to be closely associated with host immune reactions to Helicobacter pylori. AIM: To investigate humoral immune responses in patients with MALT lymphoma to antigens shared by H pylori and human gastric epithelial cells. METHODS: Sera were obtained from H pylori positive patients with MALT lymphoma (n = 11) or other gastroduodenal diseases (peptic ulcer, n = 40; non-ulcer dyspepsia, n = 20) and from H pylori negative healthy control subjects (n = 10). Antibodies to HGC-27 human gastric epithelial cells and human recombinant heat shock protein (Hsp) 60 were examined using an enzyme linked immunosorbent assay (ELISA) and immunoblotting. RESULTS: Antibody titres to HGC-27 cells were significantly elevated in H pylori positive patients with MALT lymphoma when compared with titres in patients with other gastroduodenal diseases and in healthy subjects. Immunoblotting of sera from patients with MALT lymphoma often detected a band with a molecular mass corresponding to Hsp60, and both ELISA and immunoblotting showed elevated antibody titres to the recombinant human Hsp60. Antigenic similarity between Hsp60 and H pylori HspB was documented by immunoblotting experiments. CONCLUSIONS: Autoantibodies reactive with host gastric epithelial cells are often increased in MALT lymphoma, and Hsp60 is a major target antigen. Immune responses induced by immunological cross reactivity between H pylori HspB and human Hsp60 in gastric epithelium may be involved in the development of MALT lymphoma.

Adult↗
PubMed1999

Clinicopathological features of serrated adenoma of the colorectum: comparison with traditional adenoma.

AIM: Serrated adenoma is a recently described category of colorectal adenoma. The aim of this study was to determine whether serrated adenomas have clinicopathological findings distinct from "traditional" adenoma. METHODS: Colonoscopy records for 1995-1998 were reviewed, and all traditional adenomas and serrated adenomas identified. Tumour site and endoscopic configuration were compared between the two types of adenoma. In polypectomised lesions, size and grade of dysplasia were compared between the two groups. RESULTS: There were 3305 traditional adenomas and 43 serrated adenomas. Serrated adenomas were more often found in the rectosigmoid colon than the traditional adenomas (67.5% v 41.2%, p = 0.0008). Polypectomy was more often done for serrated adenomas (27 of 43 lesions, 62.8%) than for traditional adenomas (626 of 3305 lesions, 18.9%, p < 0.0001). Size (mean (SD) maximum dimension, 12 (6) mm v 13 (3) mm) and incidence of high grade dysplasia (14.8% v 13.6%) in endoscopically removed specimens were not different between the two types. CONCLUSIONS: The therapeutic judgement applied to the management of traditional adenoma seems to be appropriate for serrated adenoma.

Adenoma↗
PubMed1999

Surgical treatment of lumbar canal stenosis in the elderly.

The effectiveness of spinal surgery for lumbar canal stenosis was investigated in the elderly. 164 patients with lumbar canal stenosis were surgically treated over 8 years. 125 patients were followed up by letter questionnaire. The outcome and patient satisfaction with the surgical procedures were compared between the 73 younger patients (< or = 64 years of age) and the 52 elderly patients (> or = 65 years of age). Intermittent claudication was satisfactorily improved in both the younger and the elderly groups. Both simple laminectomy and laminectomy with fusion could equally improve the symptoms of intermittent claudication. Although statistically not significant, there was tendency that laminectomy plus fusion effectively improved the symptoms of back pain and leg pain in both groups. 75% of the younger patients and 67% of the elderly were pleased with the outcome. The present study shows that elderly patients with lumbar canal stenosis should be actively considered for surgical treatment.

Adult↗
PubMed1999

Immunohistochemical staining of DNA topoisomerase IIalpha in human gliomas.

OBJECT: The enzyme DNA topoisomerase IIalpha (Topo IIalpha) was tested as a measure of cell proliferation in gliomas. METHODS: Immunostaining for the Topo IIalpha and for the Ki-67 antigen (MIB-1 antibody) was performed in paraffin-embedded tissue sections obtained from 25 resected human gliomas. Additionally, cultured human glioma cells were subjected to simultaneous flow cytometry to determine Topo IIalpha and DNA content. Using flow cytometric analysis, the authors found that the Topo IIalpha antibody labeled cells in the S, G2, and M phases of the cell cycle and also those in some parts of the G0 and G1 phases. In histological sections, Topo IIalpha showed more distinct staining than MIB-1, particularly in older archival cases. The proliferative indices (PIs) based on cells staining for MIB-1 and Topo IIalpha correlated highly with one another (r = 0.96). The Topo IIalpha PI immunopositivity was seen in 4.07% of cells in the low-grade astrocytoma group, 11.97% in the anaplastic astrocytoma group, and 13.84% in the glioblastoma multiforme group, representing significant differences between low-grade astrocytoma and both anaplastic astrocytoma and glioblastoma. A Topo IIalpha PI less than 5% predicted longer patient survival (p = 0.003). CONCLUSIONS: Immunostaining for Topo IIalpha represents a useful alternative to MIB-1 as a proliferative index in human gliomas.

Adolescent↗
PubMed1999

[Object analysis of cervical lymph nodes using MRI turbo-STIR sequence in cases of head and neck tumors].

Diagnosis of cervical lymph nodes from head and neck tumors was studied using MRI turbo-STIR (short TI inversion recovery) sequence and conventional MRI sequence in 15 patients. After the MRI examination, 10 of the 15 patients underwent radical neck dissections. The detection of cervical lymph nodes with the conventional MRI was not clear. However, MRI turbo-STIR depicted clear cervical lymph node margins by selectively suppressing fat signals. Thus, the accuracy of diagnosis of cervical lymph nodes by the turbo-STIR was higher than by conventional MRI. On the other hand, differential diagnosis between metastatic and non-metastatic lymph nodes remains difficult only by turbo-STIR. These findings suggest that MRI turbo-STIR sequence is more useful in the detection of cervical lymph nodes than the conventional MRI methods.

Aged↗
PubMed1999

[Endoscopic sinus surgery for unilateral chronic sinusitis].

Functional endoscopic sinus surgery has become an increasingly popular treatment for chronic sinusitis. This approach is aimed at re-establishment of ventilation and mucociliary clearance of the sinuses. However, some otolaryngologists believe that the Caldwell-Luc procedure should be routinely used for unilateral chronic sinusitis, because it is often associated with the maxillary sinus carcinomas. To evaluate the state of endoscopic sinus surgery for the diagnosis and treatment of unilateral chronic sinusitis, we analyzed the cases of 39 patients with unilateral chronic sinusitis who underwent endoscopic sinus procedures. These patients were unresponsive to appropriate antibiotic management for more than 6 months. Generally, endoscopic ethmoidectomy and antrostomy were performed with preservation of the middle turbinate. After the ostium was enlarged, the maxillary sinus was cleaned and carefully inspected for the presence of associated neoplasms using 30 and 70 degree endoscopes. Preoperative computed tomography (CT), postoperatve pathologic diagnosis, fiberscopic findings of the maxillary sinus, and symptomatic improvement were evaluated. Three patients had CT evidence of bone destruction of the lateral nasal wall. Pathological diagnosis demonstrated that three patients had maxillary sinus mycoses caused by Aspergillus species, one patient had inverted papilloma, and the other 35 patients had chronic sinusits. No associated malignancy was found. Eighty-one percent of the patients had almost normal endoscopic findings of the maxillary sinus by postoperative fiberscopic examination 4 to 8 months following surgery. With an average follow-up of 26 months, 88% of the patients were judged as having significantly improved in their presenting complaints of mucopurulent rhinorrhea, nasal obstruction, and facial pain. The results of this series suggest that endoscopic sinus surgery is an effective procedure for the diagnosis and treatment of unilateral chronic sinusitis.

Adult↗
PubMed1999

[Direct Gram staining of blood culture sample enabled the early diagnosis of brain abscess due to Listeria monocytogenes].

A 58 year old woman had a long history of immunocompromised state. Since age 28 she had multiple endocrine neoplasm type 2A: her thyroid gland and bilateral adrenal glands were removed because of pheochromocytoma and thyroid medullary carcinoma. Corticosteroid and levothyroxine were supplemented. At age 57 she was afflicted with systemic lupus erythematodes and nephrotic syndrome. Prednisolone therapy was started. Two months later she developed fever, lethergy, headache and left hemiparesis. MRI revealed multiple ring-enhancing lesions in the right cerebrum. CSF was negative for microorganisms. Blood culture hemolysed after 24 hours. Direct gram staining of the blood culture sample revealed gram-positive short rods without spore, suggested listeria. This enabled prompt initiation of high dose penicillin therapy before the official report of listseria infection. Neurological abnormality including left hemiparesis disappeared completely within one month. Enhancement of abscess wall decreased every month, but it persisted for five months despite continuous intravenous penicillin therapy. Listeria monocytogenes is well-recognized as an opportunistic pathogen. It requires prolonged therapy with antibiotics, since it is the intracellular organism. Monitoring of the brain abscess wall by the enhanced MRI is useful to determine the completion of therapy. Since listerial contamination is common among raw meat and unpasteurized milk, immunocompromised patients should be alarmed not to eat uncooked food products.

Bacteriological Techniques↗
PubMed1998

Effects of an antisense oligodeoxynucleotide for neuropeptide Y mRNA on in vivo luteinizing hormone-releasing hormone release in ovariectomized female rhesus monkeys.

The present study examines the effects of an antisense oligodeoxynucleotide (AS) for human neuropeptide Y (NPY) mRNA on in vivo LHRH release using the push-pull perfusion method in female ovariectomized monkeys. After 6 h of control perfusion, 10 microM of the AS NPY was infused for 8 h, which was followed by an additional 4 h of control perfusion. As a control for AS, an oligodeoxynucleotide containing the same bases in a scrambled sequence (SC) was similarly examined. LHRH and NPY levels in perfusate samples, collected in 10-min fractions, were measured by RIA. AS NPY infusion resulted in a significant decrease in mean NPY release starting 2 h after the initiation of infusion, and continuing until shortly after the end of AS infusion (P < 0.05, n = 7). AS NPY also suppressed mean LHRH release significantly (P < 0.05, n = 7): the AS NPY-induced LHRH suppression started 2 h after the initiation of AS infusion, and continued throughout AS infusion, lasting for the entire period of the experiment. In contrast, SC NPY resulted in neither significant changes in NPY release nor LHRH release. These data suggest that NPY release in the stalk-median eminence plays an important role in the control of pulsatile release of LHRH in vivo in the rhesus monkey.

Animals↗
PubMed1998

Chemo-enzymatic synthesis of calcitonin derivatives containing N-linked oligosaccharides.

Eel calcitonin derivatives containing various N-linked oligosaccharides were chemo-enzymatically synthesized by the transglycosylation reaction of Mucor hiemalis endo-beta-N-acetylglucosaminidase (Endo-M) to a glycosylated calcitonin derivative [Asn(GlcNac)3]-CT in which N-acetyl-D-glycosamine (GlcNAc) is attached to the L-asparagine (Asn) residue of the peptide.

Acetylglucosamine↗
PubMed1998

Energy metabolism of the gastrocnemius and soleus muscles during isometric voluntary and electrically induced contractions in man.

1. Phosphocreatine (PCr) and intracellular pH detected by 31P NMR in the gastrocnemius and soleus muscles were evaluated in order to compare the anaerobic ATP costs of voluntary and electrically induced exercise. Continuous isometric contraction at 40% of maximum force and repeated isometric contractions at approximately 75% of maximum force (contraction plus relaxation period of 0.5 s plus 2 s) were studied. 2. Anaerobic ATP turnover in soleus and gastrocnemius muscles was slower during continuous voluntary contraction than during continuous electrically induced contraction (0.36 +/- 0.04 versus 0.63 +/- 0.05 mmol (kg wet wt)-1 s-1, P < 0.05, in soleus; 0.19 +/- 0.03 versus 1.04 +/- 0.04 mmol (kg wet wt)-1 s-1, P < 0.001, in gastrocnemius). 3. There was no significant difference in anaerobic ATP turnover between voluntary and electrically induced exercise when repeated brief contractions were performed (0.22 +/- 0.05 and 0.30 +/- 0.04 mmol (kg wet wt)-1 s-1, respectively, for the soleus muscle and 0.57 +/- 0.03 and 0.66 +/- 0.07 mmol (kg wet wt)-1 s-1, respectively, for the gastrocnemius muscle). 4. During continuous voluntary contraction, in contrast to continuous stimulated contraction, anaerobic ATP turnover was slower (P < 0.05) in the gastrocnemius than in the soleus muscle, which also showed a higher electromyogram amplitude (41.1 +/- 1.1% of maximum) than the medial gastrocnemius muscle (21.4 +/- 3.6% of maximum, P < 0.001). 5. Anaerobic ATP turnover was faster (P < 0.05) in the gastrocnemius than in the soleus muscle during brief voluntary and brief electrically induced contractions. 6. The results show that the anaerobic ATP costs were higher for electrically induced exercise than for voluntary exercise when continuous submaximal contraction was performed but not when brief high-intensity contractions were performed. The gastrocnemius muscle contributes to total force production relatively less than the soleus muscle during continuous voluntary plantar flexion at 40% of the maximum voluntary contraction.

Adenosine Triphosphate↗
PubMed1998

Vestibular evoked myogenic potentials in patients with acoustic neuromas.

BACKGROUND: To diagnose acoustic neuromas (ANs), the auditory brainstem response test and the caloric test have been used in addition to magnetic resonance imaging. The auditory brainstem response and the caloric tests mainly reflect functions of the auditory pathway, ie, the cochlear nerve and the superior vestibular nerve, respectively. Because the vestibular evoked myogenic potential (VEMP) has been thought to originate in the inferior vestibular nerve, we hypothesized that the VEMP could provide different information from the auditory brainstem response and the caloric test and that it could be helpful in diagnosing ANs. In other words, we hypothesized that the VEMP could provide information concerning inferior vestibular nerve involvement in patients with ANs. OBJECTIVE: To find out if the VEMP could be useful in classifying ANs according to the involved nerves. DESIGN: We reviewed preoperative clinical tests, including VEMPs, in 21 patients (8 men, 13 women) with ANs confirmed surgically and histopathologically, comparing them with VEMPs in 8 normal subjects (5 men, 3 women). RESULTS: Whereas the first positive-negative peak of the VEMP, P13-N23, was ipsilaterally present on stimulation of the unaffected side in all patients with ANs and both sides in all normal subjects, it was absent on the affected side in 15 patients (71%) and significantly decreased in amplitude in 2 patients (9%). Thus, 17 (80%) of the 21 patients showed abnormal VEMPs. Three patients had abnormal VEMPs although they had normal caloric responses. Three patients had abnormal caloric responses although they had normal VEMPs. CONCLUSION: These results suggest that the VEMP could be useful for the diagnosis of AN, especially for classifying ANs according to the involved nerves.

Adult↗
PubMed1998

Video-enhanced microscopic visualization of apoptotic cell death caused by anti-Fas antibody in living human glioma cells.

To study the morphological changes of anti-Fas antibody-mediated apoptosis in living U251-SP human glioma cells, we employed video-enhanced contrast differential interference contrast (VEC-DIC) microscopy. In our previous study, we investigated the susceptibility of human glioma cell lines to anti-Fas Immunoglobulin M (IgM) antibody. U251-SP cells express Fas antigen on their surface. The cells exposed to anti-Fas antibody underwent apoptotic cell death, as reported previously. In this study, morphological changes of apoptosis characterized by bleb formation, shrinkage of cells, and nuclear condensation were observed under VEC-DIC microscopy in U251-SP human glioma cells treated with anti-Fas antibody. These results demonstrate the usefulness of VEC-DIC microscopy to study the process of apoptotic cell death.

Antibodies↗
PubMed1998

Effect of human interferon beta gene transfer upon human glioma, transplanted into nude mouse brain, involves induced natural killer cells.

We investigated the immunological responses induced by human interferon beta (IFNbeta) gene transfer in human gliomas produced in the brains of nude mice. A suspension of human glioma U251-SP cells was injected into the brains of nude mice. The IFNbeta gene was transferred by intratumoral injection with cationic liposomes or cationic liposomes associated with anti-glioma monoclonal antibody (immunoliposomes). When intratumoral injection of liposomes or immunoliposomes containing the human IFNbeta gene was performed every second day for a total of six injections, starting 7 days after tumor transplantation, complete disappearance of the tumor was observed in six of seven mice that had received liposomes and in all seven mice receiving immunoliposomes. In addition, experimental gliomas injected with immunoliposomes were much smaller than those injected with ordinary liposomes following delayed injections beginning 14 days after transplantation. An immunohistochemical study of the treated nude mouse brains revealed a remarkable induction of natural killer (NK) cells expressing asialoGM1 antigen. To investigate the significance of NK cells in the antitumor effect, we injected liposomes or immunoliposomes containing the human IFNbeta gene into tumors in nude mice depleted of NK cells by irradiation and anti-asialoGM1 antibody administration. The antitumor effect of the liposomes or immunoliposomes was abolished. Subsequent subcutaneous glioma challenge of the nude mice after intracerebral tumor implantation and gene transfer resulted in no subcutaneous tumor growth. These results suggest that the induction of NK cells is important in the cytocidal effect of liposomes or immunoliposomes containing the human IFNbeta gene upon experimental gliomas.

Animals↗
PubMed1998

Motor unit activation patterns during concentric wrist flexion in humans with different muscle fibre composition.

Muscle activity was recorded from the flexor carpi radialis muscle during static and dynamic-concentric wrist flexion in six subjects, who had exhibited large differences in histochemically identified muscle fibre composition. Motor unit recruitment patterns were identified by sampling 310 motor units and counting firing rates in pulses per second (pps). During concentric wrist flexion at 30% of maximal exercise intensity the mean firing rate was 27 (SD 13) pps. This was around twice the value of 12 (SD 5) pps recorded during sustained static contraction at 30% of maximal voluntary contraction, despite a larger absolute force level during the static contraction. A similar pattern of higher firing rates during dynamic exercise was seen when concentric wrist flexion at 60% of maximal exercise intensity [30 (SD 14) pps] was compared with sustained static contraction at 60% of maximal voluntary contraction [19 (SD 8) pps]. The increase in dynamic exercise intensity was accomplished by recruitment of additional motor units rather than by increasing the firing rate as during static contractions. No difference in mean firing rates was found among subjects with different muscle fibre composition, who had previously exhibited marked differences in metabolic response during corresponding dynamic contractions. It was concluded that during submaximal dynamic contractions motor unit firing rate cannot be deduced from observations during static contractions and that muscle fibre composition may play a minor role.

Adult↗
PubMed1998

Deficits in the control of the attentional focus in chronic schizophrenics.

The ability to control the size of the attentional focus and thus to modulate processing efficiency was investigated using simple reaction times in central vision in 17 chronic schizophrenic patients and 17 normal control subjects. The size of the attentional focus was manipulated by varying the size of a central box (i.e., a pre-cue), where the imperative stimulus appeared. In accordance with previous studies, in normal controls reaction time increased with box size. In contrast, in schizophrenic patients reaction time did not depend on box size. That is, schizophrenic patients did not show the inverse relation between size of the box and speed of processing, which is observed in normal controls. These results suggest that a deficit in controlling the size of the attentional focus is a basic impairment in chronic schizophrenia. It was also found that schizophrenics are more susceptible than controls to paracontrast.

Adult↗