Search PubMed⌕ Search

Biomedical subjects

K Shimada

Publications and source records attributed to K Shimada.

At least 955 records · Page 53Linked to original sources
PubMed1993

[Molecular biology of endothelium-platelet interactions and thrombogenesis].

The net effect on vascular reactivity and thrombosis resulting from interactions of the endothelium with platelets is diverse. Platelet-endothelium interactions include platelet attachments to the vessels and the release of endothelium-derived platelet inhibitors. Identification of the platelet thrombin receptor revealed a unique proteolytic mechanism of receptor activation. The myriad of receptors, ligands, and the associated generation of intracellular messengers by heterotypic interactions offers numerous attractive targets for therapeutic intervention.

Amino Acid Sequence↗
PubMed1993

Localized sclerosing cholangitis in the intrapancreatic bile duct. Report of a case.

A case of primary sclerosing cholangitis (PSC) localized in an isolated segment of the intrapancreatic bile duct was successfully treated by a pancreatico-duodenectomy. Although a progressively larger number of patients with PSC have recently been reported, there have been no other reports of a patient with this disease confined to the very distal part of the common bile duct. Since it is difficult to differentiate this rare disease from malignancy, surgical treatment as for a malignancy is sometimes required.

Bile Ducts↗
PubMed1993

[Clinical studies on ceftriaxone in respiratory tract infections. CTRX Study Group].

We report that the results of clinical studies on ceftriaxone (CTRX) in respiratory tract infections (RTIs). Clinical efficacies and side effects of CTRX were as follows; 1. Clinical efficacies of CTRX in a total of 61 cases with RTIs were excellent in 11 cases, good in 23, fair in 11, poor in 12 and unknown in 4. Thus the overall clinical efficacy rate was 59.6%. In cases of patients with lung cancers, the efficacy rate was 42.9%. 2. Clinical efficacy rates with once daily dosage were 50.0% with a dose level of 1 g CTRX and 54.8% with that of 2 g CTRX. 3. Side effects were observed in 2 cases (3.1%) and laboratory abnormalities were observed in 1 case (1.6%). They were not serious, however. These data suggest that CTRX is one of the useful cephalosporins in treatment of RTIs.

Adult↗
PubMed1993

[Hormonal regulation in cardiac function--endocrine, paracrine, autocrine].

The vasoactive peptide hormones, such as endothelin, renin-angiotensin, and endothelium-derived relaxing factor, have traditionally been viewed as an endocrine system. Recent data demonstrate that their genes and their products are expressed at many local tissue sites. The concept that multiple tissues synthesis peptides has changed out understanding of the physiology of peptide hormone, and this indicated that the autocrine and paracrine system may be important in the regulation of local tissue functions in addition to the circulation endocrine system. Patients with congestive heart failure had markedly higher circulating endothelin-1 level than normal subjects, associated with an activated renin-angiotensin system. Endothelium-dependent vasodilation is attenuated in patients with heart failure. This impaired local vasodilation may contribute to abnormalities in vasoconstriction that are characteristic of heart failure.

Endothelins↗
PubMed1993

[A case of cryptococcal retinochoroiditis associated with acquired immunodeficiency syndrome].

A case of cryptococcal retinochoroiditis associated with acquired immunodeficiency syndrome (AIDS) is reported. The patient was a 22-year-old man with hemophilia A. He was found seropositive for human immunodeficiency virus three years ago. He was admitted with complaints of fever and cough. CD4/CD8 ratio was 0.01 and CD4 lymphocyte count was 10/mm3. Two weeks later, ophthalmological examination revealed some yellowish white focal lesions at the posterior fundus. More detailed examinations were impossible because of his poor general condition. He died one month later. The autopsy showed disseminated cryptococcosis. Ocular histopathological examination revealed cryptococcal retinochoroiditis without any inflammatory reaction. This is the first report in Japan of this disease associated with AIDS and of a histopathological study of it.

AIDS-Related Opportunistic Infections↗
PubMed1993

[Two adult cases with corrected transposition of the great arteries treated with permanent endocardial pacemaker implantation].

[Case 1] A 32 year-old male had (I, D, D) type corrected transposition of the great arteries (cTGA) associated with ventricular septal defect and pulmonary stenosis. [Case 2] A 69 year-old male had (S, L, L) type cTGA associated with tricuspid regurgitation. Both cases showed advanced atrioventricular (AV) block due to HV block. Both patients had endocardial DDD pacemakers implanted, with no complication. (I, D, D) type cTGA is rarely accompanied with AV block, while the incidence of AV block is high in (S, L, L) type cTGA. We speculate that this results from the difference in the position of the AV node between these two types.

Adult↗
PubMed1993

[Ocular manifestations in human immunodeficiency virus seropositive patients].

Ocular manifestations in 56 human immunodeficiency virus (HIV) seropositive patients were examined prospectively. Eighteen of them had acquired immunodeficiency syndrome (AIDS), 14 had AIDS-related complex (ARC), and 30 were asymptomatic carriers (AC). Two AIDS patients progressed from ARC and four ARC patients from AC. Seventy-two percent of AIDS patients had ocular manifestations, including cotton-wool spots (28%), retinal hemorrhages (44%), cytomegalovirus retinitis (28%) and papilledema (6%). We also found ocular signs in 50% of ARC patients and 40% of AC patients. Since ophthalmologic manifestations are common in HIV seropositive patients, it is necessary for them to undergo a routine series of ophthalmologic examinations.

AIDS-Related Complex↗
PubMed1993

Long-term results after resection of hepatocellular carcinoma: experience of 480 cases.

The long-term outcome in 480 patients with primary hepatocellular carcinoma (HCC) who underwent hepatic resection between 1980 and 1990 was investigated. Overall 5- and 10-year survival rates were 44.1% and 17.8%, respectively, with a hospital mortality rate of 3.1%. The survival of patients who underwent curative resection was better than that of patients treated with noncurative resection. Tumor invasiveness, defined by the presence of vascular invasion and/or intrahepatic metastases, was a major prognostic factor for early recurrence in the patients treated with curative resection. The effect of tumor size and number on prognosis was attributable to a strong correlation with tumor invasiveness. One-third of patients with multiple lesions were considered to have multicentric disease, and their prognosis was better than that of patients with invasive lesions. The width of the resection margin did not affect the prognosis. An unfavorable effect of associated liver disease, especially cirrhosis, was prominent in the later period. A beneficial effect of anatomically systematic resection was apparent in non-cirrhotic patients with non-invasive HCC.

Adolescent↗
PubMed1993

[Role of hypertension in atherosclerosis].

Hypertension is frequently associated with clinical cardiovascular complications due to atherosclerosis. However, several previous studies have showed that incidence of cardiovascular complication due to atherosclerosis hypertensives do not decrease even when the blood pressure was well controlled. The effects of hypertension on atherogenesis appears to be mainly due to two factors: (1) The mechanical stress which induces the change of cell functions of arterial wall cells such as endothelial cells, smooth muscle cells and extracellular matrix, (2) Vasoactive substances, such as angiotensin and endothelin, which may plays a role for smooth muscle cell proliferation. The tropic changes in smooth muscle cells induced by above two factors in hypertension might reflect common alternations in cellular reactivity as observed in atherosclerosis. If so, hypertension and atherosclerosis could be regarded as two effects with one underlying cause.

Animals↗
PubMed1993

[Surgical treatment of stage IVa thymoma].

The relationship between prognosis of the disease and the type of surgery were reviewed in 110 cases of thymoma. Surgical procedures were classified into four types: total resection (TR), subtotal resection (SR), partial resection (PR) and exploratory thoracotomy (ET), and the extent of the disease was expressed as stage I through IV based on Masaoka's classification. Ten-year survival rates for stage III and IVa diseases were 5 6.2% in TR, 37.9% in SR and 30.3% in PR. None of the patients in ET survived more than 28 months. Tumor death after surgery was not observed in TR. Two of three patients with stage IVa disease who underwent TR are alive without recurrence of the tumor at 37 months and 6 months after surgery. The pleuropneumonectomy was performed in the former case. One of four patients who underwent SR and one of three patients who underwent PR both with stage IVa disease are alive at 71 and 150 months after surgical intervention, respectively, in spite of the presence of the tumor relapse. In these patients, repeated chemotherapy and radiotherapy were administered following the resection of the primary lesion. In conclusion, it was indicated that the improvement of the survival rate could be obtained by resection the tumor as completely as possible in stage III and IVa thymoma, as long-term survival has been proved to be possible by macroscopically complete removal of the primary site and pleural disseminations followed by combined adjuvant therapy in patient with stage IVa disease.

Adolescent↗
PubMed1992

Photoaffinity labeling of the phylloquinone-binding polypeptides by 2-azidoanthraquinone in photosystem I particles.

A photoaffinity label, 2-azido-9,10-anthraquinone, binds at the quinone-binding (Q phi) site with high affinity and can substitute for the secondary acceptor, phylloquinone, in photosystem I reaction center of spinach. Phylloquinone-depleted photosystem I particles reconstituted with azido[3H]anthraquinone were illuminated with UV light and analyzed by sodium dodecylsulfate-polyacrylamide gel electrophoresis. The large core polypeptides (psaA and/or psaB) were selectively labeled. The labeling was competitively inhibited in the presence of anthraquinone. These results indicate that the Q phi site is located on psaA or psaB polypeptides.

Affinity Labels↗
PubMed1992

A novel transthyretin mutation associated with familial amyloidotic polyneuropathy.

We characterized the mutation associated with familial amyloidotic polyneuropathy in a Japanese patient. Sequence analysis of polymerase chain reaction-amplified exons of the transthyretin gene revealed a novel point mutation resulting in a substitution of arginine for glycine at position 47. The mutation was confirmed using allele-specific olgonucleotide hybridization procedures. This most likely represents a de novo mutation since neither parent carries the mutant allele.

Adult↗
PubMed1992

Specific detection of acetyl-coenzyme A by reversed-phase ion-pair high-performance liquid chromatography with an immobilized enzyme reactor.

A selective chromatographic detection system for the determination of acetyl-coenzyme A (CoA) is reported. The short-chain acyl-CoA thioesters were separated by reversed-phase ion-pair high-performance liquid chromatography (HPLC), and then acetyl-CoA was selectively detected on-line with an immobilized enzyme reactor (IMER) as a post-column reactor. Thio-CoA liberated enzymatically from acetyl-CoA was determined spectrophotometrically after reaction with Ellman's reagent in the reagent stream. The IMER with phosphotransacetylase had a substrate specificity sufficient to determine acetyl-CoA and was active and stable in the mobile phase containing methanol and the ion-pair reagent. The calibration graph was linear between 0.2 and 10 nmol, with a detection limit of 0.05 nmol. This HPLC system with detection by IMER allows the selective identification and determination of acetyl-CoA in a mixture of acetoacetyl-CoA and 3-hydroxy-3-methylglutaryl-CoA, which are difficult to separate with ion-pair HPLC.

Acetyl Coenzyme A↗
PubMed1992

Determination of idebenone in rat serum and brain by high-performance liquid chromatography using platinum catalyst reduction and electrochemical detection.

A high-performance liquid chromatographic determination of idebenone, a new cerebral metabolism-improving agent, in rat serum and brain has been developed. After separation of idebenone on a reversed-phase column, idebenone was reduced once in a platinum catalyst reduction column connected on-line, then monitored quantitatively by electrochemical detection. A linear relationship between the peak-height ratio of idebenone to the internal standard and idebenone concentration was observed in the range 0.015-50 ng with a detection limit of 5 pg (signal-to-noise ratio = 5). This method was satisfactorily rapid and sensitive, and was successfully applied to the determination of idebenone in rat serum and brain tissues.

Animals↗