Biomedical subjects

H Imai

Publications and source records attributed to H Imai.

At least 325 records · Page 18Linked to original sources

PubMed1993

Over-expression of p53 protein in human laryngeal carcinoma.

We examined the expression of tumor-suppressor protein p53 in a variety of laryngeal carcinomas from 43 patients (25 primary, 13 metastatic and 5 recurrent cases), 13 normal laryngeal tissues and 7 benign laryngeal nodule biopsy specimens, using the polyclonal antibody CM-1. Previously we have reported a high incidence of ras mutations (51%) and human papillomavirus (HPV) infection (37%) in these laryngeal carcinomas. p53 protein was detected by immunohistochemistry in 65% of laryngeal carcinomas (60% of primary, 69% of metastatic and 80% of recurrent cases). No correlation was found between p53 over-expression and histological grading of the tumors. None of the specimens from normal larynx and laryngeal nodules revealed any detectable level of this protein. Furthermore, 11 (69%) of 16 HPV-positive cases and 17 (77%) of 22 cases with ras mutation showed variable grades of p53 expression. Twelve (71%) of 17 laryngeal carcinomas in current study having both p53 over-expression and ras mutation were moderately or poorly differentiated. Likewise, positivity for these 2 parameters was significantly increased in metastatic tumors (9 of 13 cases, 69%) as compared with primary and recurrent tumors (8 of 30 cases, 27%) (p < 0.01). Our results suggest that multiple factors are involved in this malignancy, and that the simultaneous over-expression of p53 and the presence of ras mutation may be related to the progression stage of laryngeal carcinoma.

Adult↗

PubMed1993

Increasing titers and changing specificities of antinuclear antibodies in patients with chronic liver disease who develop hepatocellular carcinoma.

BACKGROUND: Patients with liver cirrhosis and chronic hepatitis are at high risk for development of hepatocellular carcinoma (HCC). In HCC and other malignant neoplasms, antinuclear antibodies (ANA) have been detected, but the clinical and biologic significance of these autoantibodies has not been established. This study documents changing ANA manifested as seroconversion from a negative to positive ANA status, increasing titers, and changing antibody specificities in patients in whom chronic liver disease has progressed to HCC. METHODS: Sera were collected from patients with chronic liver diseases and HCC in Japan. Indirect immunofluorescence was used to detect ANA, and Western blotting, two-dimensional immunoblotting, and enzyme-linked immunosorbent assay were used to characterize nuclear antigen-antibody systems. RESULTS: ANA were detected in 57 of 183 (31%) patients with HCC, a statistically higher frequency than in patients with the most common antecedent clinical conditions, liver cirrhosis (9 of 64 patients [14%]; P < 0.05) or chronic hepatitis (16 of 123 patients [13%]; P < 0.001). One patient with autoimmune hepatitis observed for 9 years had a decrease in ANA titer after therapy with corticosteroid and azathioprine and had a rebound increase in ANA titer associated with development of HCC. Immunologic assays demonstrated dramatic decreases in levels of autoantibodies to histones during therapy and the appearance of new autoantibodies coincident with HCC. Changes in ANA associated with the appearance of auto-antibodies of new specificities were documented in four other patients with chronic liver disease in whom HCC developed. CONCLUSIONS: Changes in ANA, especially alterations in autoantibody specificities, are seen infrequently in systemic autoimmune diseases. It is possible that in HCC such changes in ANA might reflect autoimmune responses to intranuclear antigens that are perturbed in cellular transformation.

Adult↗

PubMed1993

Helicobacter pylori, dietary factors, and atrophic gastritis in five Japanese populations with different gastric cancer mortality.

In a cross-sectional study of 634 men aged 40 to 49 years, randomly selected from five areas of Japan with different rates of gastric cancer mortality, 121 men of 624 evaluated were diagnosed as having atrophic gastritis through serum pepsinogen I < 70 ng/ml and the pepsinogen I (PGI)/pepsinogen II (PGII) ratio < 3.0. We examined the relation of Helicobacter pylori (H. pylori) antibodies and dietary factors, including plasma level of antioxidant micronutrients, to the presence of atrophic gastritis. Presence of H. pylori IgG antibodies was associated with increased risk of atrophic gastritis (odds ratio [OR] = 1.9, 95 percent confidence interval [CI] = 1.1-3.3). As the level of plasma beta-carotene increased, we found a steady decrease in the risk of atrophic gastritis (OR for second quartile = 0.7, third quartile = 0.6, fourth quartile = 0.4, with CI = 0.2-0.8). Frequent intake of yellow vegetables also was associated with lower risk, while frequent intake of soybean products was related to increased risk. Although H. pylori antibodies, beta-carotene level, and intake of soybean products were all significant in the multivariate analysis, these factors did not explain the differences in atrophic gastritis prevalence among the five regions. The analysis of these risk factors in relation to each pepsinogen marker showed that although both H. pylori infection and low plasma beta-carotene were associated with the decreased level of serum PGI/II ratio, the former was derived from the increase of PGII, which is common in early stage of atrophic gastritis, and the latter from the decrease of PGI, which is specific to severe atrophic gastritis.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed1993

Hypoxanthine phosphoribosyltransferase activity in bovine embryos during the early embryonic development.

The activity of hypoxanthine phosphoribosyltransferase (HPRT) was determined in the bovine embryo during early embryonic development. Microassay, using [(3)H] hypoxanthine, was improved to measure enzyme activity in the embryonic extract. This activity depended on the reaction time and the concentration of phosphorybosyl pyrophosphate (PRPP) in a reaction. mixture. Maximum activity was obtained at 4 hours of reaction time and at a concentration of 1 mM PRPP, but was much lower than the activity recorded in the mouse embryo. During early embryonic development, HPRT activity rapidly increased beyond the 8-cell stage. When distributions and activities of HPRT, adenine phosphorybosyltransferase (APRT), and the ratio of HPRT: APRT were examined in individual blastocysts, HPRT activity was broadly distributed, but it did not clearly show the bimodal distribution expected. Six of demi-embryos with high or low HPRT:APRT ratios were transferred to recipient cows from which 2 calves were obtained. Both offspring were of the sex predicted by the HPRT: APRT ratio. These results indicate that HPRT activity of bovine preimplantation embryos can be microassayed using radiolabeled hypoxanthine, and this assay could provide an alternative method for embryo sexing.

Journal Article↗

PubMed1993

2-Buten-4-olide (2-B4O) inhibits type II collagen-induced arthritis in Lewis rats.

2-Buten-4-olide (2-B4O) is an endogenous substance which suppresses appetite and/or food intake. We studied its effect on type II collagen-induced arthritis (CIA) in Lewis rats, an animal model for human rheumatoid arthritis. Bovine type II collagen with incomplete Freund's adjuvant was injected intradermally into Lewis rats to induce CIA. 2-B4O (50 or 100 mg/kg) significantly inhibited the expression of the clinical symptoms when administered i.p. daily from day 1 to 21 after immunization. Furthermore, administration of 2-B4O daily from day 15 to 21 significantly reduced the severity of symptoms in established CIA. In addition, the progression of soft tissue swelling and articular bone erosions were suppressed by daily administration of 2-B4O. 2-B4O also significantly suppressed the delayed-type hypersensitivity (DTH) response to type II collagen at doses of 50 and 100 mg/kg. Finally 2-B4O significantly inhibited the formation of anti-type II collagen antibody at a dose of 100 mg/kg, but not at 50 mg/kg. These results suggest that 2-B4O has the strong inhibitory effects and therapeutic usefulness effects on CIA through the suppression of immune responses to type II collagen.

4-Butyrolactone↗

PubMed1993

Case report: intestinal infarction after an aneurysmal occlusion of superior mesenteric artery in a patient with Behçet's disease.

A patient with Behçet's disease, accompanied by a large aneurysm of superior mesenteric artery, developed an ischemic enteritis with multiple perforated ulcers. The ischemic necrosis of the intestine preceded by recurrent abdominal pain was due to an aneurysmal occlusion of superior mesenteric artery, but not entero-Behçet's disease. This is the first case report of intestinal infarction that occurred in a patient with vasculo-Behçet's disease involving the superior mesenteric artery. Vasculo-Behçet's disease should be included in a differential diagnosis of acute mesenteric artery thrombosis.

Adult↗

PubMed1993

Antigen-specific proliferative response of peritoneal exudate lymphocytes primed with antigen and bacterial lipopolysaccharide: the roles of Ia+ accessory cells and IL-2.

In vitro antigen-specific proliferation was investigated in a lymphocyte population that had been taken from the peritoneal exudate cells (PEC) of C3H/HeN mice (Iak) primed in vivo with both bacterial lipopolysaccharide (LPS) and horse red blood cells (HRBC) and had been purified by passage through a nylon fiber column (Nfc). The proliferative response of the Nfc-passed lymphocytes primed with HRBC and LPS [T(HRBC+LPS) cells] depended on the dose of antigen in the cultures, and the response was higher than that of cells prepared from mice primed with HRBC alone [T(HRBC) cells]. No response was seen in the cells prepared from the LPS-primed mice [T(LPS) cells] or normal mice [T(N) cells]. The response of the T(HRBC) cells was abolished by previous treatment of the cells with anti-Iak antibody and complement (C), whereas the response of the T(HRBC+LPS) cells was retained after the same treatment, indicating that the Ia- T(HRBC+LPS) cells can proliferate in response to antigen in spite of Ia+ accessory cell-depletion. Supernatants from the cultures of Ia- T(HRBC+LPS) cells in the presence of HRBC showed abundant IL-2 activity, while those of Ia- T(HRBC) cells did not. The IL-2 should be produced by the L3T4 cell population in T(HRBC+LPS) cells in response to antigen, since the previous treatment of the cells with anti-L3T4 antibody and C abrogated the production.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

PubMed1993

Does high gastric cancer risk associated with low serum ferritin level reflect achlorhydria? An examination via cross-sectional study.

With respect to the inverse association of serum ferritin level (SFL) with the risk of gastric cancer (GC) observed in some recent epidemiologic studies, possible mediation by achlorhydria as well as atrophic gastritis (AG), both of which are strongly associated with GC risk at not only the individual but also the population level, was examined in a cross-sectional study of 634 men aged 40 to 49 years randomly selected from 5 populations in Okinawa, Iwate, Nagano, Akita and Tokyo. AG and achlorhydria were serologically diagnosed based on the criteria of pepsinogen (Pep) I level < 70 ng/ml and Pep I/Pep II ratio < 3.0, as described previously, and a serum gastrin level of over 140 pg/ml, respectively. In the results, while the mean SFL for all the subjects differed significantly by area, similar areal differences in SFL were also found even when only the non-AG cases were considered. However, both of the above differences were eliminated with the exception of those between Okinawa and each of the other 4 areas, when adjustments were made for medical histories of diabetes mellitus, ulcers and liver disease, body mass index and gamma-glutamyltranspeptidase level. Therefore, no correlation among the 5 areas was observed between the adjusted areal mean SFLs and GC mortality in either case.(ABSTRACT TRUNCATED AT 250 WORDS)

Achlorhydria↗

PubMed1993

A case of successful pregnancy and delivery after brain metastasis of choriocarcinoma.

This is report regarding a 28-year-old woman who conceived and delivered a healthy child following treatment for brain metastasis of choriocarcinoma in 1980 and a prolonged postoperative disease-free period. The patient had delivered a hydatidiform mole. Eight months afterwards she was admitted to our hospital with occipital pain, vomiting and stupor, and upon CT examination was found to have a brain tumor. The surgically removed tumor was pathologically diagnosed as choriocarcinoma. Postoperative methotrexate chemotherapy rapidly lowered the preoperative urinary human chorionic gonadotrophin (19 IU/ml), and allowed restoration of the preoperative LH level, consciousness, ambulation, and manifest ovulation. Occasional mild cramps were received by continuous use of anticonvulsants which did not affect her daily life. Four and one-half years postoperatively she conceived, and had a healthy boy weighing 2,294 g at the 39th week of gestation in June 1985. Both mother and baby have been doing well for 7 postpartum years.

Adult↗

PubMed1993

Intermittent high-dose vitamin C therapy in patients with HTLV-I associated myelopathy.

The efficacy of intermittent high-dose vitamin C therapy was evaluated in seven patients with HTLV-I-associated myelopathy (HAM). All HAM patients responded well to this therapy without serious side effects. Grade of disability score improved at 9.7 (SD 5.8) months after the therapy from 7.1 (3.3) to 3.6 (2.0) (p < 0.01). Serum immunosuppressive acidic protein was elevated before and decreased after the therapy from 747 (316) to 398 (86) micrograms/ml (p < 0.05), suggesting favourable immunomodulatory action of vitamin C therapy in HAM patients.

Adult↗

PubMed1993

Inverted Bruns' nystagmus in arachnoid cysts of the cerebellopontine angle.

A 9-year-old girl with huge, double arachnoid cysts at the cerebellopontine angle is reported. After a cyst-peritoneal shunt operation, she developed fine, high-frequency gaze nystagmus towards the lesion side combined with coarse, large amplitude nystagmus in the opposite direction, which is the reverse of the Bruns' nystagmus. We call this reverse phenomenon 'inverted' Bruns' nystagmus. As the nystagmus disappeared after a second shunt operation, the nystagmus was presumed to be caused by the cystic lesion.

Arachnoid Cysts↗

PubMed1993

Autoantibodies in viral hepatitis-related hepatocellular carcinoma.

Patients with hepatocellular carcinoma (HCC) develop autoantibodies to nuclear and nucleolar antigens (ANAs) which can be readily detected by immunofluorescence on cell substrates. The frequency of ANAs in HCC is 31% (57/184). The identity of three autoantigens was established as: NOR-90, nucleolus organizer region (doublet) polypeptides involved in RNA polymerase I transcription; fibrillarin, a component of nucleolar U3 RNP involved in pre-ribosomal RNA processing, and nucleophosmin/protein B23, a nucleolar protein involved in ribosome maturation and cell proliferation. Changes in ANAs were observed in some patients during transition from chronic liver disease to HCC and were manifested as seroconversion from ANA-negative to ANA-positive status by an increase in titers and changes in ANA specificities. Serum from a patient during this transition period was used to isolate a cDNA clone encoding a novel nuclear protein with structural motifs characteristic of a family of splicing factors. These observations support the notion that ANA responses in HCC might be driven by intracellular events related to transformation from the stage of chronic injury to the stage of malignancy. Changes in ANA profiles which were observed to precede clinically diagnosed HCC in some patients might be early markers of transformation.

Autoantibodies↗

PubMed1993

Novel nuclear autoantigen with splicing factor motifs identified with antibody from hepatocellular carcinoma.

A patient with liver cirrhosis who progressed to hepatocellular carcinoma was found to develop novel antinuclear antibodies. The serum was used to isolate full-length cDNA clones encoding related proteins of 530 amino acids (representative clone HCC1.4) and 524 amino acids (representative clone HCC1.3). Affinity-purified antibodies eluted from recombinant proteins recognized a 64-kD nuclear protein in Western blotting and decorated the nucleoplasm in a speckled-network fashion in immunofluorescence, colocalizing with antibodies to pre-mRNA splicing factor SC35 and uridine-rich small nuclear RNAs. The deduced amino acid sequence contained an arginine/serine-rich (RS) domain and three-ribonucleoprotein consensus sequence domains, two classes of motifs present in several splicing factors. A repeating octapeptide of Arg-Ser-Arg-Ser-Arg(Lys)-Glu(Asp)-Arg-Lys(Arg) was present in RS region of HCC1. This octapeptide sequence called RS-ERK motif was also found in splicing factors U2AF 35- and 65-kD proteins and 70-kD U1 small nuclear ribonucleoprotein. The molecular features and immunolocalization data suggest that the HCC1 autoantigen may be associated with splicing activities and are consistent with observations that autoantibody responses frequently target molecules involved in important cellular biosynthetic functions.

Amino Acid Sequence↗

PubMed1993

Kidney diseases among the elderly--a clinicopathological analysis of 247 elderly patients.

We describe the clinicopathological features of 247 patients over the age of 60 with renal disorders. We acceded the histological classification of WHO recommendation, except for IgA nephropathy as primary glomerulonephritis. All nephrotic patients other than those with diabetic glomerulosclerosis (DGS) or amyloidosis were treated with steroids and/or immunosuppressants. Clinical data showed 88 patients with nephrotic syndrome. The histological study revealed that 142 patients had primary renal diseases and 105 patients had secondary renal diseases. Of 88 nephrotic patients, 35 were membranous nephropathy (MN) and 9 were minimal change nephrotic syndrome (MCNS). In secondary nephrosis, amyloidosis and DGS were diagnosed in 9 and 7 patients, respectively. A good response to therapy was obtained in MN (89%) and MCNS (78%). However, nephrotic patients with mesangial proliferative glomerulonephritis, amyloidosis, or DGS had unfavorable outcomes. Histological observations are useful aids in estimating the prognosis and therapy selection for renal disorders even in elderly patients.

Age Factors↗

PubMed1993

Immune complex type crescentic glomerulonephritis accompanied with perinuclear anti-neutrophil cytoplasmic antibodies.

A 70-year-old male developed rapidly progressive glomerulonephritis syndrome with serum perinuclear anti-neutrophil cytoplasmic antibodies (P-ANCA). A renal biopsy showed diffuse crescentic glomerulonephritis. Immunofluorescence microscopy revealed 2+ granular staining of IgG over the mesangial area and along glomerular capillary walls. Electron microscopy showed scattered deposits in the paramesangial area. These morphologic findings were consistent with those of immune complex type crescentic glomerulonephritis (IC-CGN). Serum C3, C4, and CH50 were within normal limits, and circulating immune complexes were not detected by C1q-binding assay, but both P-ANCA and anti-myeloperoxidase antibodies were positive. A possible relation of P-ANCA to IC-CGN is discussed.

Aged↗

PubMed1993

Acute myelogenous leukemia associated with a mediastinal tumor.

We describe a 45-year-old female who developed acute myelogenous leukemia (AML) associated with a mediastinal mass. The patient achieved a complete remission accompanied by resolution of the mediastinal mass following intensive chemotherapy alone. A review of the literature disclosed ten AML patients with a mediastinal tumor; all five patients who had mediastinal granulocytic sarcoma treated by local irradiation prior to developing AML, eventually relapsed as frank leukemia and died soon afterwards. On the other hand, three of the other five patients who simultaneously developed both a mediastinal tumor and overt AML achieved complete remission with combination chemotherapy. In conclusion, intensive chemotherapy should be considered for a patient with granulocytic sarcoma of the mediastinum, irrespective of the concomitant leukemia.

Antineoplastic Agents↗

PubMed1993

[Hereditary progressive dystonia with marked diurnal fluctuation (HPD)].

HPD is a clinical entity characterized by childhood-onset postural dystonia, which shows marked diurnal fluctuation (aggravation of symptoms towards evening and their alleviation in the morning after sleep), and dramatic and sustained response to levodopa without any adverse effects, such as wearing-off or dyskinesia. Since the first report by Segawa et al. (1971), many cases have been reported under the title HPD or related nomenclature. In this review, we describe details of clinical features and recent laboratory studies of HPD, to differentiate it from other disorders manifesting dystonia in childhood. It has been suggested that HPD has a genetically determined abnormality, being restricted to the terminals of the nigrostriatal dopaminergic neurons, which results in reduced dopamine content.

Circadian Rhythm↗

PubMed1993

The role of gallium scintigraphy, computerized tomogram scan, and magnetic resonance imaging angiography in the diagnosis of Takayasu's disease.

A 25-year-old Japanese woman had fever and general fatigue for 3 months. Examination revealed no abnormalities in her pulse or blood pressure. Gallium 67 scintigraphy demonstrated an abnormal uptake in the right supraclavicular and anterior chest regions. A plain computerized tomogram (CT) scan revealed ringed high densities in the ascending and descending aorta and the left common carotid artery, however, an enhanced CT scan showed only irregular aortic walls. Angiography gave a final diagnosis of Takayasu's disease. Magnetic resonance imaging (MRI) angiography also demonstrated complete occlusive stenosis of the left common carotid artery and right subclavian artery. Our case suggests the usefulness of gallium 67 scintigraphy, plain CT scan and MRI angiography in the active phase or early diagnosis of Takayasu's disease.

Adult↗