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Biomedical subjects

A Imamura

Publications and source records attributed to A Imamura.

At least 109 records · Page 6Linked to original sources
PubMed1994

High intensity in the globus pallidus on proton and T2-weighted MRI in a case of dentato-ruburo-pallido-luysian atrophy of myoclonus epilepsy type.

Although marked atrophy of the tegmentum of the mid-brain is a known computed tomography (CT) and magnetic resonance imaging (MRI) feature in patients with dentato-ruburo-pallido-luysian atrophy (DRPLA), this is the first report of marked high signal intensity of the globus pallidus on proton and T2-weighted MR images in a patient in the early stage of DRPLA of the myoclonus epilepsy type. We suggest that the globus pallidus may be involved in the early stage of DRPLA of this type. Magnetic resonance imaging is considered to be useful for the early detection of involvement of the globus pallidus and in the clinical diagnosis of DRPLA.

Adolescent↗
PubMed1994

Fever of unknown origin: a review of 80 patients from the Shin'etsu area of Japan from 1986-1992.

In this survey involving 10 hospitals, we analyzed data on 80 Japanese patients from the Shin'etsu area (Nagano-ken and Niigata-ken) who were observed for fever of unknown origin (FUO). Our objectives were to identify the underlying causes and the relevant diagnostic methods. Fourteen of the patients died of the underlying illness. The cause of the FUO was infection in 43 patients, allergic or autoimmune disease in 13, neoplasm in 7, miscellaneous causes in 3, and undetermined in 14. FUO was self-limited in 13 patients and persistent in one patient. Methods successfully used to establish the final diagnosis in 66 patients were: evaluation of the clinical course or response to treatment in 16, serologic tests in 12, bacteriologic studies in 10, biopsy in 9, cytologic examination in 6, conventional radiology in 6, necropsy in 3, endoscopy in 2, and biochemical testing in 2.

Adolescent↗
PubMed1994

[Studies on neurogenic bladder due to human T-lymphotropic virus type-I associated myelopathy (HAM)].

Fifty cases of untreated human T-cell lymphotropic virus type I (HTLV-I) associated myelopathy (HAM) were evaluated by urodynamic studies to clarify the nature of urinary disturbance and to find out suitable urological treatment. Both irritative and obstructive symptoms coexisted in the HAM patients. 38% of the patients experienced only urinary symptoms throughout the affected period. A main cause of frequency was detrusor hyperreflexia at filling phase, which was found in 58% of the patients. However, decreased effective bladder capacity due to large amount of residual urine was possibly an another cause of frequency. Detrusor sphincter dyssynergia was the main cause of difficulty of urination, but in some cases underactive detrusor at voiding phase was also the cause of difficulty of urination. Hydronephrosis was observed in only 5 kidneys, although as many as 30 out of 46 cases (65.2%) showed bladder deformity. 17 cases (34%) had urinary tract infection at first visit. As the activity of daily living was deteriorated, the mean volume of residual urine, incidence of detrusor hyperreflexia and detrusor sphincter dyssynergia were all increased. Medical treatment was effective to relieve subjective symptoms, but urodynamic examination did not necessarily review improvement. Intermittent catheterization was needed and successful in 64% of all cases. Patients with HAM must be carefully followed up by urologists.

Adult↗
PubMed1993

A phase II study of combination therapy with 5'-deoxy-5-fluorouridine and cisplatin in the treatment of advanced gastric cancer with primary foci.

BACKGROUND: 5'-Deoxy-5-fluorouridine (5'-DFUR, doxifluridine) is a recently developed prodrug of oral 5-fluorouracil (5-FU), which is used clinically in Japan for the treatment of gastric, colorectal, and breast cancer. 5-FU has been reported to act synergistically with cisplatin (CDDP) in experimental and clinical studies. The authors conducted a multicenter Phase II study of combination therapy with 5'-DFUR and CDDP to evaluate the therapeutic usefulness of this regimen in the treatment of unresectable and advanced gastric cancers with primary foci. None of the patients had previously undergone chemotherapy. Their ages ranged from 27 to 75 years and performance status was grade 0 to 3. METHODS: 5'-DFUR (1400 mg/m2/d) was administered orally on days 1 through 4 and 15 through 18, and CDDP (80 mg/m2/d) was injected intravenously on day 5. This treatment cycle was repeated every 4 weeks. An independent panel of specialists evaluated the clinical response. RESULTS: Fifty-one patients were studied. Clinical evaluation of response was possible in 43 patients who met the protocol requirements. The overall response rate was 50.0% (14 of 28, 95% confidence limits, 30.7%-69.4%) for patients with measurable lesions. The median duration of response was 5.2 months (156 days). The overall median survival time was 8.9 months (268 days) for evaluated patients. Therapeutic toxicity of World Health Organization (WHO) grade > or = 3 was manifested as anorexia and nausea or vomiting in 20.9% and 18.6% of the patients, respectively. However myelotoxicity and nephrotoxicity of WHO grades 3 and 4 occurred in less than 10% of the patient group. No drug-related mortality occurred. CONCLUSIONS: Combined therapy with 5'-DFUR and CDDP is a safe and effective treatment regimen for advanced gastric cancers with primary foci which stresses the patient's quality of life, especially when used in an outpatient setting.

Adenocarcinoma↗
PubMed1993

An ab initio molecular orbital study on effect of electric field strength on ionic selectivity of the sodium channel.

The effect of electric field strength of the selectivity filter on ionic selectivity of the sodium channel has been studied by ab initio molecular orbital calculations. On the basis of the previous method, two kinds of model systems, the FCO2M system and the FCO2M-H2O system, were studied. In this study, a FCO2- molecule, which is substituted for a HCO2- molecule, was used as a model for the selectivity filter. This substitution corresponds to weakening the electric field strength of the selectivity filter. For this system, geometries of ground and transition states were optimized with MINI-3 basis sets. The FCO2-H2O system, for which we evaluated thermochemical parameters and cross-sections, is a good model for ionic permeation of the sodium channel. When the results of the FCO2M-H2O system were compared with those of the HCO2M-H2O system, we concluded that permeabilities of Li+ and Na+ are smaller and that of K+ is larger as the field strength of the selectivity filter is weakened. Namely, the permeation of K+ is relatively favorable when the field strength of the selectivity filter is weakened. This conclusion is in accordance with the prediction of Eisenman's theory.

Animals↗
PubMed1992

Elevated fibrinopeptide A (FPA) in patients with Lesch-Nyhan syndrome.

The detection of elevated fibrinopeptide A (FPA) level in a patient with the Lesch-Nyhan syndrome complicated with cerebral infarction prompted us to examine FPA level in 3 other patients with the syndrome. FPA level significantly increased in all patients. Fibrinopeptide B beta 15-42 (FPB beta 15-42) level was increased in two, and both beta-thromboglobulin (beta TG) and platelet factor 4 (PF4) levels were elevated in one patient. These results suggest coagulation abnormalities in patients with Lesch-Nyhan syndrome.

Adolescent↗
PubMed1992

Mucosal immune defence mechanisms in enterocolitis complicating Hirschsprung's disease.

Enterocolitis remains an important cause of morbidity and mortality in Hirschsprung's disease. The aetiology of enterocolitis is uncertain-ischaemic and bacterial causes and recently, rotavirus infections, have been suggested. Bowel tissue from 12 patients with Hirschsprung's disease who underwent Swenson's operation (five of whom had clinical evidence of enterocolitis) and colon from six controls subjects were examined to investigate possible immunopathological mechanisms associated with the disease. IgA, IgM, and J chain (but not IgG) containing plasma cells were significantly increased in the lamina propria along the entire length of resected bowel in enterocolitis patients, compared with non-enterocolitis patients and controls (p less than 0.01). Luminal secretory component staining of the anganglionic segment of colon from enterocolitis patients was considerably reduced. Lamina propria CD68 positive monocyte/macrophages and CD45RO positive leukocytes were increased in enterocolitis patients compared with non-enterocolitis patients (p less than 0.01). CD57 positive natural killer (NK) cells showed a unique distribution pattern compared with other cell types. Patients with enterocolitis showed a significant increase in CD57 positive NK cells in the lamina propria of ganglionic bowel only (p less than 0.05). NK cell values in ganglionic bowel of non-enterocolitis patients and in aganglionic bowel in all patients were similar to controls. The diversity of altered local immune response seen in this study may reflect a multifactorial microbial aetiology in enterocolitis associated with Hirschsprung's disease.

Antigens, CD↗
PubMed1992

Reactivity of P-glycoprotein monoclonal antibodies in childhood cancers.

P-Glycoprotein (P-gp), the product of the mdr-1 gene, is implicated in the development of chemoresistance in a variety of, mostly adult, cancers. Its role in paediatric tumours, most of which are non-epithelial in origin, has yet to be fully elucidated. A study was undertaken to investigate reactivity of two P-gp monoclonal antibodies (MAbs), JBS-1 and MRK16, recognising cytoplasmic and surface epitopes, respectively, of the P-gp molecule, in a variety of newly diagnosed and relapsed childhood cancers. P-gp was not expressed in any of 36 tumours examined (neuroblastoma 13, nephroblastoma 12, rhabdomyosarcoma 6, lymphoma 3, teratoma 1, Ewings 1), 14 of whom had chemoresistant disease. Reactivity to both MAbs was also investigated in patients with acute leukaemia. Out of 10 diagnostic acute lymphoblastic leukaemia (ALL) samples, a positive reaction with JSB-1 was observed in 1 patient who failed to remit on standard induction therapy and in 3 of 6 patients in ALL relapse, only 1 of whom showed low grade positivity with MRK16. Both MAbs reacted positively in 1 patient with acute non-lymphocytic leukaemia (ANLL) at diagnosis who achieved remission with teniposide and cytosine arabinoside, but relapsed 7 months later and was again positive with both Mabs. JSB-1 also showed varying degrees of positivity in 4 out of 4 other patients in ANLL relapse. It would therefore appear that P-gp is unlikely to mediate chemoresistance in most solid tumours of childhood, but may well play a major role in the development of chemoresistance in acute leukaemia.

ATP Binding Cassette Transporter, Subfamily B, Mem↗
PubMed1992

Novel disease-modifying antirheumatic drugs. I. Synthesis and antiarthritic activity of 2-(4-methylphenyl)benzothiazoles.

A series of 2-(4-methylphenyl)benzothiazoles was synthesized and evaluated using an adjuvant-induced arthritic rat model. This class of desired compounds affecting the immune response was found using hemagglutination assay. 4-Acetoxy-2-(4-methylphenyl)benzothiazole (7m), KB-2683, was most potent in the adjuvant-induced arthritic rat model and selected for further evaluation. In contrast to nonsteroidal antiinflammatory drugs, compound 7m showed no antiinflammatory or analgesic activities. It did, however, show an immunomodulatory activity in enhanced delayed type hypersensitivity.

Animals↗
PubMed1992

[Usefulness of renal CT scan for analysis of nutcracker phenomenon].

Among 24 patients with confirmed left renal bleeding, 11 were diagnosed of having nutcracker phenomenon (NP) on the basis of the results of renal venography and pull-back pressure from the left renal vein to the inferior vena cava. Renal CT scan was performed for these 11 patients, and its usefulness as a means of diagnostic analysis was studied. The following results were obtained. 1. The left kidney was scanned at 5-mm intervals. The mean distance between the anterior surface of the abdominal aorta (Ao) and the posterior surface of the superior mesenteric artery (SMA) was 4.5 +/- 0.6 mm in the NP group, while it was 13.9 +/- 6.4 mm in the control group (p < 0.01). 2. Regarding the morphology of the left renal vein (LRV), tapering dilatation, i.e., funnel-like dilatation, from the left side of Ao was seen in the NP group. In the control group, the left renal vein showed a club-like shape continuing to the inferior vena cava and showed no dilatation. 3. Vascular structures indicative of collateral vessels were observed around the LRV in the NP group. If renal CT scan is performed at 5-mm intervals, the following CT finding are thought to be indicative of the nutcracker phenomenon; (1) a distance of 5 mm or less between Ao and SMA and (2) tapered dilatation of the LRV. This study suggests that renal CT scan is useful for diagnostic analysis of the nutcracker phenomenon.

Adolescent↗
PubMed1991

Evaluation of a new calcium containing cardioplegic solution in the isolated rabbit heart in comparison to a calcium-free, low sodium solution.

Isolated perfused rabbit hearts were studied to compare the effects of 3 hour ischemic arrest following either calcium-free or calcium-containing cardioplegia, on the recovery of isovolumic function of the left ventricle, coronary flow, release of creatine phosphokinase and myocardial water content. The hearts perfused with the calcium-containing solution (Ca 0.5 mmol/L) showed better recovery of the developed pressure in the left ventricle, and its first derivative and compliance. Coronary flow at a constant perfusion pressure was better restored during reperfusion in the hearts with calcium-containing solution. The release of less CPK and a lower water content were also observed in the hearts reperfused with calcium-containing solution. We concluded that calcium-containing cardioplegic solution with a high concentration of magnesium (10 mmol/L) was superior to calcium-free solution for myocardial protection.

Animals↗
PubMed1991

Case report: the incidental lipid embolization to the brain and kidney after lymphography in a patient with malignant lymphoma: CT findings.

Lipid embolization to the brain and kidney is reported, confirmed by computed tomography (CT) following lymphography in a man with malignant lymphoma. The patient complained of headache and unstable gait and became blind and hemiplegic immediately after the examination. With supportive therapy he recovered from the complications in 5 months except for slight gait disturbance, probably explained by cerebral infarction. Mechanisms of the combined brain and renal embolization are discussed.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1991

Left preureteral vena cava (retrocaval or circumcaval ureter) associated with partial situs inversus.

We present a rare case of left preureteral vena cava associated with partial situs inversus. A 68-year-old woman was referred to our clinic for further study of left hydronephrosis on computerized tomography. The abdominal viscera were in mirror image and the heart was levocardia. The middle portion of the left ureter was dorsal to the left inferior vena cava. The left ureter was reanastomosed ventral to the inferior vena cava. To our knowledge, coexistence of preureteral vena cava and partial situs inversus has not been reported previously in the literature.

Aged↗
PubMed1991

Clinical manifestation of human T-cell lymphotropic virus type-I-associated myelopathy and vesicopathy.

Patients with human T-cell lymphotropic virus type I (HTLV-I)-associated myelopathy (HAM) sometimes have accompanying voiding disturbances. We performed clinical surveys and urodynamic examinations on 25 untreated patients with HAM. Although 4 cases (16%) were entirely aware of urinary symptoms, the onset of urinary symptoms preceded other pyramidal symptoms in 6 cases (24%). All cases suffered from dysuria. The cause of dysuria was thought mainly to be detrusor external sphincter dyssynergia, but in some cases an underactive detrusor and poor opening of the bladder neck at voiding were also the causes of dysuria. There was a tendency for urinary dysfunction to become worse as the primary disease progresses. Patients with HAM must be carefully followed up by urologists in order to prevent deterioration of the urinary tract.

Adult↗