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Biomedical subjects

S Shimizu

Publications and source records attributed to S Shimizu.

At least 613 records · Page 34Linked to original sources

A Novel Delta5-Desaturase-Defective Mutant of Mortierella alpina 1S-4 and Its Dihomo-gamma-Linolenic Acid Productivity.

A novel Delta5-desaturase-defective mutant was derived from an arachidonic acid-producing fungus, Mortierella alpina 1S-4, after treating the parental spores with N-methyl-N'-nitro-N-nitrosoguanidine. The mutant produced only a trace (about 1%) amount of arachidonic acid, and the ratio of dihomo-gamma-linolenic acid (DGLA) to total fatty acids in each lipid class was markedly high, accounting for as much as 60% in phosphatidylcholine. Under submerged batch culture conditions, the mutant produced 2.4 g of DGLA per liter (43.3% of total fatty acids) when grown at 28 degrees C for 7 days in a 5-liter jar fermentor. The other major (more that 1%) fatty acids were palmitic acid (21.2%), stearic acid (9.6%), oleic acid (14.3%), linoleic acid (4.4%), and gamma-linolenic acid (5.8%). About 80 mol% of the DGLA produced was found in triacylglycerol.

Journal Article↗

Protective effects of sesamin against liver damage caused by alcohol or carbon tetrachloride in rodents.

The effects of sesamin, a potent inhibitor of delta 5-desaturase in polyunsaturated fatty acid biosynthesis, on the fatty acid compositions of tissue lipids and liver functions were examined in rodents. When a mixture of sesamin and episesamin (51.1:48.2, w/w) was given to rats at a dietary level of 0.5% for 13 days, the proportions of dihomo-gamma-linolenic acid significantly increased not only in the liver but also in plasma and hemocytes, suggesting an interference with delta 5-desaturation by these lignans. The sesamin preparation at the dietary level of 1% improved changes in various blood parameters of the mouse, such as aspartate aminotransferase and alanine aminotransferase activities, and the concentrations of total cholesterol, triglyceride and total bilirubin, caused by continuous inhalation of ethanol. In addition, sesamin showed a significant protective effect against the accumulation of fat droplets and vacuolar degeneration in the mouse liver, as confirmed on histological examination. Sesamin, at the level of 100 mg/kg body weight, also tended to prevent liver lipid accumulation by carbon tetrachloride in mice. These results indicate that sesamin and a related lignan compound have an ability to improve liver function.

Administration, Inhalation↗

Transvaginal hysterosonography for differential diagnosis between submucous and intramural myoma.

Thirty-six patients with hypermenorrhea, dysmenorrhea, and/or anemia were examined by transvaginal sonography (TVS) and by transvaginal hysterosonography using an endometrial balloon catheter and saline (TVHS). Those patients who showed distinct intramural myomas by TVS were excluded from this study. Of 36 patients, 22 were diagnosed with submucous myomas, 10 with intramural myomas, and 4 with endometrial polyps by TVS, but 20 patients were diagnosed as having submucous myomas, 12 patients intramural myomas, and 4 patients endometrial polyps by TVHS. The correlation between ultrasound findings and surgery (hysterectomy or hysteroscopy) indicated that there were 13 misdiagnoses (36%) by TVS and only one misdiagnosis (2.8%) by TVHS.

Diagnosis, Differential↗

Do anger and aggression affect carotid atherosclerosis?

BACKGROUND AND PURPOSE: Although a number of metabolic and psychosocial factors have been identified as coronary risk factors, no studies have evaluated the relation between personality and cerebrovascular disease. The purpose of the present study was to elucidate the relation between the characteristics of anger or aggression and the severity of carotid atherosclerosis on the basis of the findings of B-mode ultrasonography. METHODS: The Cornell Medical Index was used to measure anger in 34 patients with signs of atherosclerosis or at least one of four recognized risk factors for atherosclerosis (hypertension, hypercholesterolemia, diabetes mellitus, and cigarette smoking). The Rosenzweig Picture Frustration Study and Yatabe-Guilford Personality Test were used to evaluate aggression. High-resolution B-mode ultrasonography was performed, and the severity of carotid atherosclerosis was determined by plaque score. The occurrence of risk factors for carotid atherosclerosis was compared among the patients. RESULTS: The correlation of plaque score with one item that endorses anger was r = .65 (P < .01) and with "extrapersistive" in aggression was r = .50 (P < .01). Multivariate analysis identified significant correlations between plaque score and age, hypercholesterolemia, and anger. CONCLUSIONS: Our results suggest that anger and, perhaps, aggression may be risk factors for cerebrovascular disease.

Aggression↗

Lymphomatous polyarthritis in patients with peripheral T-cell lymphoma.

Direct involvement of the joints is a rare complication of malignant lymphoma and lymphoma cells in synovium or synovial fluid have been characterized in only a very few cases. We report two cases of CD4-positive, HTLV-I-negative peripheral T-cell lymphomas that manifested polyarthritis infiltrated with lymphoma cells which we further characterized. Patient 1, with a prior 7-year history of cutaneous T-cell lymphoma (mycosis fungoides) and polyarthralgia, developed pain and swelling in the right knee joint and right femoral region. Patient 2 was initially diagnosed with immunoblastic lymphadenopathy, later rediagnosed as the prodromal stage of T zone lymphoma. Seven years later she developed skin eruptions, cervical lymph node swelling, polyarthritis, and pleural effusion. Synovial fluid analysis in both cases showed predominant CD3+ or cytoplasmic CD3+, CD4+, and CD8- atypical lymphoid cell infiltration. In both cases the T-cell receptor beta and gamma chains were rearranged in the synovial fluid mononuclear cells. Analysis of these two cases and a review of the literature suggest that lymphoma cell infiltration of synovium occurs preferentially in patients with CD4+ peripheral T-cell lymphoma.

Adult↗

Inhibition by methylene blue of the L-arginine metabolism to L-citrulline coupled with nitric oxide synthesis in cultured endothelial cells.

The effect of methylene blue on the metabolism of L-arginine to L-citrulline coupled with nitric oxide synthesis in cultured endothelial cells was investigated. The addition of the calcium ionophore ionomycin (10(-8)-10(-5) M) to endothelial cells stimulated L-citrulline formation from L-arginine. Ionomycin-stimulated L-citrulline formation was inhibited by NG-nitro-L-arginine (10(-6)-10(-4) M), a potent inhibitor of nitric oxide synthase. These results indicate that ionomycin-stimulated L-citrulline formation was coupled to nitric oxide synthesis. Therefore, L-citrulline formation from L-arginine was used as a marker for nitric oxide synthesis. Methylene blue (10(-4)-10(-3) M) inhibited ionomycin-stimulated L-citrulline formation in bovine aortic endothelial cells. Moreover, the formation of L-citrulline by the particulate fraction obtained from bovine cultured endothelial cells was also inhibited by methylene blue concentrations in excess of 10(-5) M. Although the addition of methylene blue to various tissues has been reported to release superoxide anions (Wolin et al., 1990; Marczin et al., 1992), inhibition of L-citrulline formation by methylene blue was not affected by the presence of superoxide dismutase (100 micrograms/mL) in either cultured endothelial cells or the particulate fraction. These findings suggest that methylene blue is a direct inhibitor of nitric oxide synthase in bovine aortic endothelial cells.

Amino Acid Oxidoreductases↗

Hyperamylasemia after hepatic resection.

It has been noticed that hyperamylasemia occurs after hepatic resection. Between July 1973 and April 1991, hyperamylasemia was observed in 57 (42%) of 136 patients with hepatocellular carcinoma and 13 (32%) of 41 patients with metastatic liver cancer. The incidence was not correlated with extent of resection, blood loss, hypoxemia, disseminated intravascular coagulation, liver cirrhosis, or hepatitis B virus infection. There were three patterns: salivary-type dominant hyperamylasemia (type I), pancreatic-type dominant hyperamylasemia (type II), and a mixture of types I and II (type III). The point at issue is whether types II and III indicate postoperative pancreatitis. Although the pathogenesis remains unclear, surgeons should be alert to this complication and take reasonable measures with regard to the types of hyperamylasemia.

Amylases↗

[A case of Sjögren's syndrome at the age of 91 with a lymphoepithelial lesion].

A 91 year old woman with Sjögren's syndrome who developed a lymphoepithelial lesion and showed an active state of the disease is described. Since June, 1990, the patient had been complaining of dry eyes and mouth and a left submandibular tumor (1.0 x 1.5 cm in diameter). A biopsy of the tumor revealed lymphoepithelial lesions in the salivary gland. Mild anemia (Hb 9.6 g/dl) and an elevated erythrocyte sedimentation rate (80 mm/hr) were noted. The gamma-globulin level was 2.7 g/dl, IgG 2789 mg/dl, IgA 469 mg/dl, RAHA x80, antinuclear antibody x20, anti-SS-A x256, thyroid test x400 and microsome test x102400. The Schirmer's test showed decreased tear secretion (Lt. 3mm, Rt. 9mm) and keratoconjunctivitis sicca were noticed by an ophthalmologist. Salivary scintigraphy revealed decreased uptake and slow excretion of the isotope (grade II). A biopsy of a minor salivary gland showed periductal lymphocytic infiltration and acinar cell destruction. Immunohistochemical analyses revealed the cross-reactive idiotype of a monoclonal rheumatoid factor which is associated with a patient with Sjögren's syndrome, in the infiltrating lymphocytes and plasma cells of the minor salivary glands, but not in the lymphoepithelial lesions of the left submandibular gland. This was a rare case concerning a 91-year old patient with Sjögren's syndrome who developed a lymphoepithelial lesion and showed high activity in the serum and gives us valuable information on the relationship between aging and autoimmunity.

Aged↗

[Acute respiratory failure resulting from diffuse microscopic pulmonary tumor emboli by bladder cancer: a case diagnosed at autopsy].

A 71-year-old man who had undergone a total cystectomy and a transureterocutaneostomy more than a year earlier was admitted to our hospital on February, 1992 because of the chief complaints of anorexia and systemic bone pain due to multiple bone metastases of bladder cancer. At two weeks after the admission, he had a sudden attack of dyspnea. His chest reontgenogram revealed no significant abnormalities. He had repeated attacks and died of respiratory failure two days after the first attack. An autopsy disclosed diffuse microscopic pulmonary tumor emboli in the pulmonary arteries and arterioles of bilateral lungs, but there was no parenchymal metastasis. The metastatic lesions in the sinusoids of the liver were also occupied by numerous tumor emboli, suggesting that the tumor emboli in the lungs had derived from those in the sinusoids. Microembolization of the whole lung area must be considered as a cause of clinically unexplained dyspnea.

Aged↗

[Long-term follow up studies of asthma in children. Prognosis of asthmatic school children of the 20 years from the first investigation].

OBJECTIVE: For the prognoses of asthmatic children, reports tend to be in severe cases because most investigations are performed in specialized facilities. We presumed that the prognoses of overall asthmatic cases including mild and moderate case might be better than that reported, we therefore reviewed cases of bronchial asthma in school children in the past 20 years to investigate the prognoses. METHOD: Cases of bronchial asthma in school children detected in an asthma survey conducted in Niigate Prefecture in 1969 were followed up in 1974 and 1982. Recently, the prognoses were studied again in 1989, 20 years after the initial survey. The subjects comprised 164 patients (125 males and 39 females). RESULTS: The most recent survey revealed that 68.7% of the subjects were without attacks, 30.4% were suffered for attacks currently and 0.7% had already died. Asthmatic attacks were mild in 83.7% of the subjects with asthma. The largest percentage of subjects (59.4% of males and 30.4% of females) became negative for attacks after they reached 11 to 14 years of age. In all four surveys, 6.3% of males and 17.5% of females were constantly positive for attacks, while 10.9% of males and 30.3% of females became negative for attacks once but subsequently experienced recurrence of the attacks. The prognoses were worse in females than in males. The subjects who continued to have attacks after they reached adolescence were observed to have attacks frequently even after they became adults. One third of subjects with attacks had remittance lasting for two years or more. Remittance was seen in the period between the age of 15 and 25 years in most cases.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗

[A case of long surviving inflammatory breast cancer with bone metastasis, treated by intra-arterial infusion chemotherapy followed by extended mastectomy].

Since there is no established therapeutic strategy in the treatment of stage IV breast cancers and there are cases with bone metastases from the breast showing long survival, the authors usually perform due local control in cases with bone metastases. The present case is an inflammatory carcinoma of the breast with bone metastasis for which doxorubicin hydrochloride was administered via the subclavian and internal thoracic arteries followed by extended mastectomy. The patient is being treated with tamoxifen citrate and doxifluridine and shows no other metastasis at this writing, four years and seven months after the mastectomy. Bone scintigraphy of the patient indicated disappearance of the bone metastases. Since there are long surviving cases among those with a poor prognosis involving inflammatory breast cancer with concomitant bone metastasis, it is necessary to treat cases with locally advanced breast cancer by preoperative intraarterial infusion together with mastectomy, ie, sufficient local control.

Bone Neoplasms↗

Establishment of a CD4-positive plasmacytoma cell line (AMO1).

A human plasmacytoma cell line (AMO1) was established. The AMO1 cells had the light and electron microscopic characteristics typical of plasmacytoma cells and did not harbor Epstein-Barr virus. These cells expressed cytoplasmic immunoglobulin A kappa and the immunoglobulin heavy-chain gene (JH) and kappa light-chain gene (C kappa) were rearranged. Coexpression of a CD4 antigen and plasma cell antigens (CD38 and PCA-1) was an unusual and sustained feature. Neither the T-cell receptor beta nor the gamma chain gene displayed the rearranged form. Other lineage-specific surface antigens, namely T, B, monocytoid, and myeloid antigens, were all negative in AMO1. In accordance with the surface CD4 expression, polymerase chain reaction analysis indicated constitutive expression of CD4 mRNA, and the cytogenetic findings revealed that AMO1 cells had a derivative chromosome 12, which had a structural abnormality of the short arm carrying the CD4 gene locus. These findings provide strong evidence for the presence of CD4-positive malignant plasma cells and raise the possibility that the CD4 expression in the AMO1 cell line is closely associated with the derivative chromosome.

Biomarkers, Tumor↗

Hepatocyte growth factor is linked by O-glycosylated oligosaccharide on the alpha chain.

The glycosylation site and the structure of O-glycosylated oligosaccharide of recombinant human HGF were investigated. N-acetylgalactosamine (GalNAc) in the alpha chain suggested the presence of O-glycosylated oligosaccharide. Sugar analysis and amino acid sequence analysis of peptide fragments produced by limited degradation revealed that O-glycosylated oligosaccharide linked to Thr445 of the alpha chain. The molecular weight of the oligosaccharide was determined with ion spray mass spectrometry. From these studies, the structure of the O-glycosylated oligosaccharide on the alpha chain of HGF was concluded as [formula: see text].

Amino Acid Sequence↗

Purification and characterization of a novel enzyme, arylalkyl acylamidase, from Pseudomonas putida Sc2.

A novel enzyme, arylalkyl acylamidase, which shows a strict specificity for N-acetyl arylalkylamines, but not acetanilide derivatives, was purified from the culture broth of Pseudomonas putida Sc2. The purified enzyme appeared to be homogeneous, as judged by native and SDS/PAGE. The enzyme has a molecular mass of approximately 150 kDa and consists of four identical subunits. The purified enzyme catalyzed the hydrolysis of N-acetyl-2-phenylethylamine to 2-phenylethylamine and acetic acid at the rate of 6.25 mumol.min-1.mg-1 at 30 degrees C. It also catalyzed the hydrolysis of various N-acetyl arylalkylamines containing a benzene or indole ring, and acetic acid arylalkyl esters. The enzyme did not hydrolyze acetanilide, N-acetyl aliphatic amines, N-acetyl amino acids, N-acetyl amino sugars or acylthiocholine. The apparent Km for N-acetylbenzylamine, N-acetyl-2-phenylethylamine and N-acetyl-3-phenylpropylamine are 41 mM, 0.31 mM and 1.6 mM, respectively. The purified enzyme was sensitive to thiol reagents such as Ag2SO4, HgCl2 and p-chloromercuribenzoic acid, and its activity was enhanced by divalent metal ions such as Zn2+, Mg2+ and Mn2+.

Amidohydrolases↗

Purification and characterization of a novel lactonohydrolase, catalyzing the hydrolysis of aldonate lactones and aromatic lactones, from Fusarium oxysporum.

A novel lactonohydrolase, an enzyme that catalyzes the hydrolysis of aldonate lactones to the corresponding aldonic acids, was purified 10-fold to apparent homogeneity, with a 61% overall recovery, from Fusarium oxysporum AKU 3702, through a purification procedure comprising DEAE-Sephacel, octyl-Sepharose CL-4B and hydroxyapatite chromatographies and crystallization. The molecular mass of the native enzyme, as estimated by high-performance gel-permeation chromatography, is 125 kDa, and the subunit molecular mass is 60 kDa. The enzyme contains 15.4% (by mass) glucose equivalent of carbohydrate, and about 1 mol calcium/subunit. The enzyme hydrolyzes aldonate lactones, such as D-galactono-gamma-lactone and L-mannono-gamma-lactone, stereospecifically. Furthermore, it can catalyze the asymmetric hydrolysis of D-pantoyl lactone, which is a promising chiral building block for the chemical synthesis of D-pantothenate. These reactions are reversible, and the reaction equilibrium at pH 6.0 has a molar ratio of nearly 1:1 with D-pantoyl lactone and D-pantoic acid. The Km and Vmax for D-galactono-gamma-lactone are 3.6 mM and 1440 U/mg, respectively, and those for D-galactonate are 52.6 mM and 216 U/mg, respectively. The enzyme also irreversibly hydrolyzes several aromatic lactones, such as dihydrocoumarin and homogentisic-acid lactone.

Amino Acid Sequence↗