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Biomedical subjects

S Hara

Publications and source records attributed to S Hara.

At least 343 records · Page 19Linked to original sources
PubMed1992

[A case of traumatic aortic valve rupture].

A case of aortic valve rupture as a result of blunt trauma by motorcycle accident is presented. A previously healthy 18-year-old male developed severe congestive heart failure 46 days after the initial trauma. There were crescentic tears in the right and non-coronary cusps parallel to and along the whole length of the cusps. The valve was excised and replaced with a 21 mm St. Jude Medical prosthesis. Following the procedure he made an relatively uneventful recovery and was discharged on the 83rd postoperative day. The possibility of damage to the heart valves in traffic accidents must be borne in mind since rapid deterioration can occur and early surgical therapy is essential.

Accidents, Traffic↗
PubMed1992

The role of oxidized lipoproteins in the pathogenesis of atherosclerosis.

1. Oxidized low density lipoprotein (LDL) has been suggested to play an important role in atherogenesis by facilitating the accumulation of lipids in macrophages. In vitro studies from this laboratory have shown that oxidized LDL is recognized not only by the specific receptor for it, but also by the receptor which is common for oxidized LDL and acetyl LDL. Probucol, originally developed as an antioxidant, prevents the oxidative modification of LDL in vitro. Recent studies by the authors show that probucol prevents the progression of atherosclerosis in homozygous Watanabe heritable hyperlipidaemic rabbits in vivo without any changes in plasma LDL cholesterol levels. 2. These results strongly suggest that oxidative modification of LDL could occur in vivo and probucol could slow the progression of atherosclerosis, without changes in plasma cholesterol levels. 3. In addition, recently the authors demonstrated that high density lipoprotein (HDL) particles are also oxidized. Once HDL particles were oxidized, they showed a lessened effect on the decrease of cholesteryl ester in foam cells, suggesting oxidative modification of HDL may stimulate development of atherosclerosis by limiting efflux of cholesterol from foam cells. Moreover, HDL particles from probucol-treated patients are hardly oxidized; subsequently, these HDL particles caused a marked efflux of cholesterol from foam cells.

Animals↗
PubMed1992

[Flow cytometric analysis of DNA ploidy pattern in breast cancer: malignant potential and prognostic implication].

Flow cytometric DNA analysis in solid tumors has developed over the past ten years. In human breast cancer, flow cytometric analysis of DNA ploidy pattern recently reported were reviewed. There are conflicting data regarding the value of DNA ploidy pattern obtained by flow cytometric analysis for determining prognosis for breast cancer patients. Some data seem to indicate that S-phase fraction alone or in combination with DNA ploidy pattern may be more important prognostically than DNA ploidy pattern alone, although the results have not been uniform. These suggests that a consensus of determination for DNA ploidy pattern in breast cancer and further investigations on DNA ploidy pattern are required.

Breast Neoplasms↗
PubMed1992

[Establishment and characterization of a human squamous cell carcinoma cell line LK-52 which produce direct activator of coagulant factor X].

Uterus origin squamous cell carcinoma cell line LK-52 was established from surgical specimen of lung metastatic nodule. LK-52 produce poorly differentiated squamous carcinoma in nude mouse, and doubling time in vitro was 38 hours. Chromosome analysis show various abnormality and main mode number was 67 and 68. LK-52 shed active procoagulant substance into culture medium. The culture medium of LK-52 shortening recalcification time of normal human plasma and factor VII or factor IX deficient plasma but not factor X deficient plasma. Procoagulant activity of LK-52 product may induced with direct activation of coagulant factor X. Procoagulant activity which produced by cancer cell may play a important roll in the unbalanced haemostasis of cancer patient.

Adult↗
PubMed1992

[Statistics on operations at Hara Genitourinary Hospital (1971-1991)].

The statistical analysis of the inpatients and operations in our department from April, 1971 to March, 1991 revealed a total of 9,170 operations. One of the biggest changes in treatment is a marked increase in closed surgery. This includes endourological surgeries; transurethral resections of prostate and bladder tumor (TUR-P, TUR-Bt), percutaneous nephrolithotripsy (PNL), transurethral uretero-lithotripsy (TUL) and extracorporeal shock-wave lithotripsy (ESWL). From 1976 to 1980 there were 721 open surgical procedures (71.0% of cases) and 295 closed procedures (21.0% of cases). This ratio has now been reversed completely. From 1986-1991, there were 342 open procedures (8.2% of cases) and 3808 closed procedures (91.8% of cases). The main reason for this change was the introduction of the new techniques PNL, TUL and ESWL. Other important observations include: The incidence of emergency operations was higher in this private institution than that seen in non-private hospitals. From 1986, there was an increase in the use of PNL and TUL for the management of urinary calculi, and from 1988, ESWL has overtaken PNL and TUL in the treatment of this condition. Recently the limitations of ESWL have been appreciated and the value of a combined approach to therapy, for selected cases, is being recognized. A total of 238 ileal or ileocecal conduits were created with good results. A low complication rate has been observed with preservation of renal function.

Female↗
PubMed1992

Antioxidant effect of calmodulin antagonists in rat brain homogenate.

Several calmodulin antagonists, W-7, amitriptyline, trifluoperazine, chlorpromazine, dibucaine, prenylamine, calmidazolium, and compound 48/80, inhibited lipid peroxidation induced non-enzymatically in rat brain homogenate by ascorbate and Fe2+. Suggestions of involvement of calmodulin in various oxidative cellular responses, based on experiments using calmodulin antagonists, may need to be re-evaluated.

Animals↗
PubMed1991

Nucleotide sequence and expression of the glucoamylase-encoding gene (glaA) from Aspergillus oryzae.

The glucoamylase-encoding gene (glaA) from Aspergillus oryzae was cloned using its cDNA as a probe, which had been isolated previously. From comparison of nucleotide (nt) sequences of genomic clones with its cDNA, the glaA gene was found to contain four short putative introns, 45-56 nt in length. The A. oryzae glaA gene shared 62% homology at the nt level with the A. niger glaA gene with the four introns located at the same position. The 5'-flanking region contained a TATA box at nt-72 from the start codon, and two putative CAAT sequences at nt-87 and -331. Genomic Southern analysis and physical mapping showed that the glaA gene is located on the smallest chromosome (3.4 Mb) of six separated bands of chromosomes. Clones containing the glaA gene, when re-introduced intro A. oryzae, resulted in a three- to eightfold increase in glucoamylase activity.

Amino Acid Sequence↗
PubMed1991

Detection of 14-kDa group II phospholipase A2 in human seminal plasma.

About 90% of phospholipase A2 activity detected in human seminal plasma reacted with monoclonal antibodies raised against human synovial fluid phospholipase A2. The crude seminal plasma yielded a pure immuno-cross-reactive phospholipase A2 preparation in a single purification step using immuno-affinity chromatography. The amino acid sequence of the N-terminal 20 residues of this seminal enzyme was determined and found to be identical with that of human synovial phospholipase A2. Thus, it is suggested that human seminal plasma contains phospholipase A2, belonging to the 14-kDa group II enzyme family, as the major isoenzyme.

Amino Acid Sequence↗
PubMed1991

Construction of a fusion gene comprising the Taka-amylase A promoter and the Escherichia coli beta-glucuronidase gene and analysis of its expression in Aspergillus oryzae.

Northern blot analysis of glucose-grown and starch-grown mycelia of Aspergillus oryzae RIB40 was conducted using the cloned Taka-amylase A (TAA) gene as a probe. The amount of mRNA homologous to the TAA gene was increased when this fungus was grown with starch as a sole carbon source. In order to analyze the induction mechanism, we inserted the Escherichia coli uidA gene encoding beta-glucuronidase (GUS) down-stream of the TAA promoter and introduced the resultant fusion gene into the A. oryzae genome. Production of a functional GUS protein was induced by starch, but not by glucose. When the effects of various sugars on expression of the fusion gene were examined, the results suggested that the expression of the fusion gene was under control of the TAA gene promoter.

Aspergillus oryzae↗
PubMed1991

Cloning and nucleotide sequence of the genomic ribonuclease T2 gene (rntB) from Aspergillus oryzae.

Using synthetic oligonucleotide probes, we have cloned a genomic DNA sequence encoding a ribonuclease (RNase) T2 gene (rntB) from Aspergillus oryzae on a 4.8 kb HindIII fragment. DNA sequence analysis of the RNase T2 revealed the following: (1) The gene is arranged as five exons and four introns; (2) The deduced amino acid sequence contains 239 amino acid residues of the mature enzyme. In addition, there exist 17 amino acid residues thought to be a signal peptide sequence at the N-terminus and 20 amino acid residues at the C-terminus; (3) The nucleotide sequence of the rntB gene is homologous to those of the RNase Rh gene from Rhizopus niveus and the S2 stylar glycoprotein gene of Nicotiana alata with degree of about 51% and 47%, respectively; (4) A. oryzae and A. nidulans transformed with the cloned rntB gene had much higher ribonuclease T2 activity than wild-type strains.

Amino Acid Sequence↗
PubMed1991

Extracellular phospholipase A2 detected at inflamed sites in rats does not originate from platelets.

Extracellular phospholipase A2 activity has been detected in caseinate-induced peritoneal fluid in rats. We studied the source of this extracellular phospholipase A2 in 'platelet-poor' rats which had been pretreated with an intravenous injection of rabbit anti-rat platelet serum. In these rats, the increase in the peritoneal fluid extracellular phospholipase A2 level at the inflamed sites was almost identical to that observed in control rats, although platelet numbers in peripheral blood were decreased markedly. This observation suggests that extracellular phospholipase A2 in the peritoneal cavity is not derived mainly from platelets.

Animals↗
PubMed1991

Effects of MPTP, MPP+, and paraquat on NADPH-dependent lipid peroxidation in mouse brain and lung microsomes.

Both MPTP and MPP+ inhibited the NADPH-dependent microsomal LPO in mouse brain and lung. On the other hand, PQ significantly stimulated the LPO in brain microsomes in a dose-dependent manner. The herbicide, however, stimulated lung microsomal LPO only in a narrow concentration range, despite much higher P450 reductase activity in lung microsomes than that in brain microsomes. These findings suggest that the effect of PQ on microsomal LPO is different from those of the analogous neurotoxins, MPTP and MPP+, and is not uniform in brain and lung.

1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine↗
PubMed1991

Evidence for heterogeneous groups of neuronal differentiation of Ewing's sarcoma.

We have investigated the capability of differentiation of Ewing's sarcoma (ES) towards a neuronal direction through the establishment of four extraosseous ES cell lines and by in vitro stimulation with dibutyryladenosine cyclic monophosphate (db-cAMP) of eight ES lines. All except one of the lines expressed the molecule defined by 5C11, the antibody specifically reactive with ES. Two ES lines expressed a 200 kilodalton (kD) neurofilament protein (NFP) although their original tumours were negative for NFP. Elongation of cytoplasmic processes and increased NFP expression were observed after db-cAMP treatment of these lines and microtubules in the cytoplasmic processes were ultrastructurally demonstrated. Six lines were NFP negative, but three lines changed their morphology after induction of 200 kD NFP expression by db-cAMP treatment. The other three showed no definitive differentiation after db-cAMP treatment. Chromosomal analysis of the new ES lines showed the typical t(11;22) in one line and a +der(22) in two lines. No correlation was observed between the chromosomal abnormality and the differentiation capability. We conclude that ES is a heterogeneous group of tumours with respect to capability of differentiation into the neuronal lineage, but it is clearly distinguished from peripheral primitive neuroectodermal tumours by its 5C11 reactivity.

Adolescent↗