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Biomedical subjects

Y Kobayashi

Publications and source records attributed to Y Kobayashi.

At least 289 records · Page 16Linked to original sources
PubMed2001

[Contrivance for frozen section diagnosis of early minute lung cancer during operation].

We reported the technique of pathological diagnosis for minute lung cancer lesion of early stage during operation. Target lesion for our technique may be less than 1 cm in size and not be detected by palpation. Our technique may superior to usual method of frozen section of tissue specimen without fixation. At first, resected lung specimen was fixed by injection of 20% formalin solution subsequent warming by microwave oven for 40 seconds. Almost all lesions may be detected in proper thickness of specimen. Specimen was washed out and steeped in the 20% of sucrose solution for 30 to 60 seconds in order to avoid crystallization of water that was contained within lung specimen. Then thin sliced section of specimen was made by Cryostat in usual method. The minute cancer lesion was able to detect more easy than usual method of making frozen section of specimen. Formalin fixed and sucrose steeped frozen section may be able to evaluate the surgical margin from cancer exactly than the section made by non-fixed specimen.

Frozen Sections↗
PubMed2001

[Cost and effectiveness of exercise therapy for patients with essential hypertension].

PURPOSE: While exercise therapy is established as an appropriate treatment for essential hypertension, its economic profile has not been fully evaluated. The purpose of this study is to evaluate cost and effectiveness in comparison with drug therapy. SUBJECTS AND METHODS: The study subjects were hypertensive patients under treatment at an outpatient clinic. Fifty-seven were selected on a non-randomized manner for exercise therapy and the same number of patients was chosen for drug therapy after matching age, sex, medication and complications. The following data were collected during three months of intervention. 1) Effectiveness: Change of systolic blood pressure before and after the intervention. 2) Cost: equipment, personnel expenses for exercise therapy and fees for health check-ups (exercise therapy); fees for consultation, laboratory examination and medications (drug therapy), 3) Cost-effectiveness: cost per 1 mmHg systolic blood pressure reduction. We evaluated the variance of cost-effectiveness by controlling the number of program participants, personnel expenses, and equipment expenses of exercise therapy. We also simulated how the cost-effectiveness of exercise therapy would improve by modifying the number of exercise participants, personnel and equipment expenses. RESULTS: The cost-effectiveness per 1 mmHg systolic blood pressure reduction was yen 11,268 for exercise therapy and yen 2,441 for drug therapy. Extending program facilities and increasing the number of participants would improve the cost-effectiveness of exercise therapy, but there were limitations to how far this could be achieved in the hospital setting. CONCLUSION: Differences in cost-effectiveness between exercise and drug therapies are attributed to differences in personnel expenses. Although they could be reduced by managerial effort of the hospital to some extent, outsourcing of exercise therapy to community-based facilities should be considered.

Cost-Benefit Analysis↗
PubMed2001

[Usefulness of 99mTc-methoxy-isobutyl-isonitrile scintigraphy for preoperative localization of adenoma in primary hyperparathyroidism].

We evaluated the usefulness of 99mTc-methoxy-isobutyl-isonitrile (MIBI) dual phase scintigraphy for detecting hyperfunctioning parathyroid adenoma. We retrospectively reviewed 18 hyperparathyroid patients who received MIBI prior to neck exploration and compared the radiological findings of MIBI with ultrasonography (US) and magnetic resonance imaging (MRI). Fifteen patients were studied with MRI, and 17 patients were examined with US. All patients were found to have a solitary parathyroid adenoma histopathologically. MIBI correctly revealed the location of 17 adenomas among 18 confirmed tumors. In our series, there was one false-positive case that was found to have thyroid adenoma. The diagnostic sensitivity of MIBI MRI and US was 94.4%, 80% and 52.5%, respectively. The positive predictive value (PPV) was 94.4% for MIBI, 81.8% for MRI and 92.3% for US. We conclude that MIBI is useful and accurate for the preoperative localization of adenoma in primary hyperparathyroidism.

Adenoma↗
PubMed2001

Negative remodeling at the ostium of the left circumflex artery.

We report an ostial lesion with negative remodeling. Coronary angiography revealed a 60% stenosis at the ostium of the left circumflex artery (LCX). Intravascular ultrasound (IVUS)-guided directional atherectomy followed by stenting was planned. However, IVUS images revealed no significant stenosis and negative remodeling at the ostium of the LCX. The lesion did not undergo intervention.

Coronary Angiography↗
PubMed2001

Actual invasive potential of human hepatocellular carcinoma revealed by in situ gelatin zymography.

BACKGROUND: The matrix-degrading proteinases are believed to play an important role in the invasion and metastasis of hepatocellular carcinoma (HCC), but no one has ever seen the in situ matrix-degrading activity in HCCs. PURPOSE: To demonstrate the cellular localization of actual gelatinolytic activity and to investigate the invasive potential of human HCC. EXPERIMENTAL DESIGN: HCC cases (30) were subjected to in situ gelatin zymography and SDS-gelatin gel zymogram. RESULTS: In situ gelatin zymography revealed a heterogeneous gelatinolytic activity in HCC cells, as well as stromal cells of noncancerous livers. The gelatinolytic intensity was stronger in 15 HCC nodules than in the corresponding noncancerous livers and was significantly associated with the cancer invasion to the capsule of the HCCs and to the portal veins. An intense gelatinolytic activity was detected in HCC cells in the front of tumor invasion. SDS-gelatin gel zymogram revealed gelatinases A and B that were mostly in latent forms. CONCLUSIONS: The present study demonstrates high gelatinolytic activity at the invasive front of HCCs at a cellular level and that HCC has an invasive potential with the gelatin (matrix)-degrading metalloproteinases. Furthermore, it suggests the importance of the activation mechanism of gelatinolytic enzymes in the invasion and metastasis of HCCs.

Carcinoma, Hepatocellular↗
PubMed2001

[Clinical and bacteriological studies of ceftriaxone (CTRX) once daily administration in pediatric patients with respiratory tract infections].

Clinical studies of ceftriaxone (CTRX) were performed at a dose of 40 mg/kg once daily to evaluate its pharmacokinetics, and clinical and bacteriological efficacies in pediatric patients with respiratory tract infections. The following results were obtained. 1. Of 45 patients, clinical responses to CTRX were excellent in 34 (75.6%), good in 9 (20.0%) and poor in 2 (4.4%), indicating the overall efficacy rate of 95.6%. 2. Haemophilus influenzae (23 strains), Streptococcus pneumoniae (20 strains) and Moraxella catarrhalis (17 strains) were isolated from the patients as the main causative organisms. MIC90 of CTRX against these detected bacteria was < or = 0.06 microgram/ml with H. influenzae [beta-lactamase (-)/ABPC (S)], 0.25 microgram/ml with H. influenzae (BLNAR), 0.05 microgram/ml with PSSP, 1.0 microgram/ml with PISP/PRSP and 2.0 micrograms/ml with M. catarrhalis, respectively. 3. The eradication rate of causative organisms was 90.0% (27/30). 4. Serum levels of CTRX after administration of a 1-hour intravenous drip infusion of 40 mg/kg were investigated in 12 patients. Mean serum level at 24 hours after the administration was 9.4 +/- 2.8 micrograms/ml, which covered the level of MIC90 throughout the 24 hours. 5. No adverse reactions related to CTRX were observed. As the approved dosage of CTRX in pediatric patients is twice daily, while it is once daily in adults, there have been few reports on the efficacy of once-daily CTRX in pediatrics. According to the results of the study, it is suggested that once-daily CTRX for the pediatric patients with respiratory tract infections is useful. Further studies might be required to establish outpatient parenteral antibiotic therapy (OPAT) in pediatric infections.

Ceftriaxone↗
PubMed2001

[Guidelines for adequate antibiotic prophylaxis after hepatic, biliary, and pancreatic surgery].

The recent spectrum of bacteria isolated from patients with hepatic, biliary, and pancreatic infections mostly consists of Gram negative rods translocated from their intestinal flora. Cephem or carbapenem antibiotics should be selected based on the severity of surgical infection and risk to each patient to prevent postoperative infections. Once postoperative infection occurs, surgical procedures such as ultrasonography-guided percutaneous biliary drainage should be performed to reduce inflammation and to obtain samples for bacterial culture. The most commonly identified bacteria after hepatic, biliary, and pancreatic surgery are Pseudomonas species, MRSA, and Enterococcus species. Previously administered antimicrobial agents should be immediately interrupted and empiric antibiotic therapy with carbapenem started. Vancomycin or teicoplanin is selected when MRSA or Enterococcus faecium infection is suspected. Infection control systems should be in place for prevention of postoperative MRSA infections.

Anti-Bacterial Agents↗
PubMed2001

Serum phenytoin concentration and IgG antibody titre to periodontal bacteria in patients with phenytoin-induced gingival overgrowth.

Epileptic patients taking phenytoin with gingival-overgrowth and those without gingival-overgrowth were compared for daily drug dose, plasma total phenytoin concentration, plasma free-phenytoin concentration and serum IgG antibody titre against 13 periodontal bacteria. Significantly higher daily drug dose was noted in patients with gingival overgrowth (P < 0.05) when compared with those without overgrowth. In addition, both total and free forms of plasma phenytoin concentration were significantly higher in sera of patients with gingival growth than of those without overgrowth (P < 0.01). Strong positive correlation was found between daily drug dose and serum phenytoin concentration in patients with gingival overgrowth, while weak correlation was found in patients without gingival overgrowth, suggesting a difference in drug metabolism in these two groups. However, no differences were found in serum IgG antibody titres to 13 periodontal bacteria examined between two groups. These results suggest that metabolic ability of phenytoin is one of the factors for developing gingival overgrowth, and that periodontal infection may not be a primary causative factor for gingival overgrowth but act as an additive factor which increase tissue mass for this unwanted side effect.

Administration, Oral↗
PubMed2000

Effect of intracoronary gamma-radiation therapy on in-stent restenosis: An intravascular ultrasound analysis from the gamma-1 study.

BACKGROUND: The aim of this study was to use serial volumetric intravascular ultrasound to evaluate the effect of gamma-radiation on recurrent in-stent restenosis. METHODS AND RESULTS: After successful reintervention, patients were randomized to receive either (192)Ir or placebo. Intravascular ultrasound studies with motorized pullback (0.5 mm/s) were performed immediately after irradiation and at 8-month follow-up in 70 patients. Paired volumetric analysis of the stented segment and of 5-mm proximal and distal reference segments was performed; this included measurements of the external elastic membrane, lumen, plaque and media (external elastic membrane minus lumen), stent, and intimal hyperplasia (stent minus lumen). Baseline proximal reference, stent, and distal reference measurements were similar in both groups. The changes in proximal and distal reference measurements of the external elastic membrane, plaque and media, and lumen areas were similar in both groups. However, the decrease in stented segment lumen volume was less in the (192)Ir patients than the placebo patients (-25+/-34 mm(3) versus -48+/-42 mm(3); P:=0.0225), and the increase in the volume of intimal hyperplasia in the stented segment was less in the (192)Ir patients than in the placebo patients (28+/-37 mm(3) versus 50+/-40 mm(3); P:=0.0352). When averaged over the length of the stented segment (32+/-13 mm versus 33+/-14 mm; P:=0.9), the increase in mean area of intimal hyperplasia was 0.8+/-1.0 mm(2) in the (192)Ir group and 1.6+/-1.2 mm(2) in the control group (P:=0.0065). Late stent-vessel wall malapposition was noted in one placebo patient and no (192)Ir patients. CONCLUSIONS: gamma-Radiation therapy can effectively prevent recurrent in-stent restenosis by inhibiting neointimal formation within the stent. At the stent edge, there were no significant differences between (192)Ir and placebo patients.

Analysis of Variance↗
PubMed2000

Selected mutations in a mesophilic cytochrome c confer the stability of a thermophilic counterpart.

Mesophilic cytochrome c(551) of Pseudomonas aeruginosa (PA c(551)) became as stable as its thermophilic counterpart, Hydrogenobacter thermophilus cytochrome c(552) (HT c(552)), through only five amino acid substitutions. The five residues, distributed in three spatially separated regions, were selected and mutated with reference to the corresponding residues in HT c(552) through careful structure comparison. Thermodynamic analysis indicated that the stability of the quintuple mutant of PA c(551) could be partly attained through an enthalpic factor. The solution structure of the mutant showed that, as in HT c(552), there were tighter side chain packings in the mutated regions. Furthermore, the mutant had an increased total accessible surface area, resulting in great negative hydration free energy. Our results provide a novel example of protein stabilization in that limited amino acid substitutions can confer the overall stability of a natural highly thermophilic protein upon a mesophilic molecule.

Bacteria↗
PubMed2000

Exaggerated vascular and renal pathology in endothelin-B receptor-deficient rats with deoxycorticosterone acetate-salt hypertension.

BACKGROUND: Endothelin (ET)-1 plays an important role in the pathogenesis of deoxycorticosterone acetate (DOCA)-salt-induced hypertension. We evaluated the pathological role of ET(B) receptors in DOCA-salt-induced hypertension, cardiovascular hypertrophy, and renal damage by using the spotting-lethal (sl) rat, which carries a naturally occurring deletion in the ET(B) receptor gene. METHODS AND RESULTS: Homozygous (sl/sl) rats exhibit abnormal development of neural crest-derived epidermal melanocytes and the enteric nervous system, and they do not live beyond 1 month because of intestinal aganglionosis and intestinal obstruction. The dopamine ss-hydroxylase (DssH) promoter was used to direct ET(B) transgene expression in sl/sl rats to support normal enteric nervous system development. DssH-ET(B) sl/sl rats live into adulthood and are healthy, expressing ET(B) receptors in adrenal glands and other adrenergic neurons. When homozygous (sl/sl) and wild-type (+/+) rats, all of which were transgenic, were treated with DOCA-salt, homozygous rats exhibited earlier and higher increases in systolic blood pressure than did wild-type rats. Chronic treatment with ABT-627, an ET(A) receptor antagonist, completely suppressed DOCA-salt-induced hypertension in both groups. Renal dysfunction and histological damage were more severe in homozygous than in wild-type rats. Marked vascular hypertrophy was observed in homozygous rats than in wild-type rats. Renal and vascular injuries were significantly improved by ABT-627. In DOCA-salt-treated homozygous rats, there were notable increases in renal, urinary, and aortic ET-1, all of which were normalized by ABT-627. CONCLUSIONS: ET(B)-mediated actions are protective in the pathogenesis of DOCA-salt-induced hypertension. Enhanced ET-1 production and ET(A)-mediated actions are responsible for the increased susceptibility to DOCA-salt hypertension and tissue injuries in ET(B) receptor-deficient rats.

Acetylglucosaminidase↗
PubMed2000

Prognostic value of genetically diagnosed lymph node micrometastasis in non-small cell lung carcinoma cases.

The predictive value of lymph node micrometastasis, detected by immunohistochemical or genetic methods, is well appreciated in terms of prognosis. However, a major problem is high false-positive rates, because most methods focus on cytokeratin, which is a component not only of carcinoma but also normal epithelial and nonepithelial cells. Mutant allele-specific amplification (MASA) can detect DNAs derived from cancer cells itself, reportedly with high sensitivity. It was, therefore, used with nested-PCR using p53 or K-ras mutation for analysis of lymph node micrometastasis in non-small cell lung carcinoma (NSCLC) patients in the present study, in comparison with the immunohistochemical method using an anti-cytokeratin reagent for the same samples. Lymph nodes from 31 NSCLC patients with p53 and K-ras mutated tumors (30 and 1, respectively) staged as pathological (p)-T1-4 N0-1 and M0 were examined. Genetic and immunohistochemical methods demonstrated positive reactions in 34 (15%) and 61 (27%) of 229 lymph nodes, respectively (9 cases, 29%, and 24 cases, 77%). The concordance with the two methods was 77%, but 13 (39%) of 34 genetically positive lymph nodes could not be detected by immunohistochemistry (IHC). Of 22 cases with p-N0 disease, 6 (27%) were genetically positive in hilar and/or mediastinal lymph nodes, and 4 (67%) of them died after cancer relapse. In contrast, none of the patients without micrometastasis died of cancer (P < 0.001, log rank analysis). Of the same p-N0 patients, 17 (77%) were positive by IHC, and 4 (24%) of them died of cancer, whereas 5 negative patients did not suffer cancer relapse. Survival did not significantly differ between cases positive and negative (P = 0.246) by IHC. According to the g-N (N factor restaged by a genetic method), patients with g-N1 and g-N2 disease had a shorter survival than those with g-N0 disease (P = 0.042 and P < 0.001, respectively). However, no significant difference was observed with grading by IHC. Thus, detection of micrometastasis in regional lymph nodes with the MASA method, in other words with a carcinoma-specific marker, is of greater prognostic significance for early stage NSCLC patients than immunohistochemical results. This approach should facilitate selection of patients for whom postoperative adjuvant chemotherapy should be performed.

Adenocarcinoma↗