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Biomedical subjects

K Kumasaka

Publications and source records attributed to K Kumasaka.

At least 19 recordsLinked to original sources
PubMed2005

Comparison of muscarinic receptor- and beta-adrenoceptor-mediated vasorelaxation between euthyroid and acute hyperthyroid rats.

Hyperthyroidism was induced by subcutaneous injections of L-thyroxine (T4) (0.5 mg/kg/day) for 3 days in order to investigate the effects of acute hyperthyroidism on the vasorelaxing responses to isoprenaline and acetylcholine in isolated rat aortae. In the aortae, there was no significant difference in isoprenaline-induced relaxation between hyperthyroid and control rats, however acetylcholine-induced relaxation was significantly greater in hyperthyroid rats than in control rats. N(G)-nitro-L-arginine (L-NOARG), an inhibitor of nitric oxide (NO) synthase, reduced isoprenaline- and acetylcholine-induced relaxations in both hyperthyroid and control rats and in the presence of L-NOARG no significant difference in the acetylcholine-induced relaxation was seen between the two groups of rats. Indomethacin, a cyclo-oxygenase inhibitor, had no significant influence on both isoprenaline- and acetylcholine-induced relaxations in both control and hyperthyroid rats. 17-Octadecynoic acid (17-ODYA), a cytochrome P-450 mono-oxygenase inhibitor, reduced the both isoprenaline- and acetylcholine-induced relaxation in both hyperthyroid and control rats, and acetylcholine-induced relaxation was still greater in hyperthyroid rats than in control rats. These results indicate that an acute hyperthyroidism significantly enhances muscarinic receptor- but not adrenoceptor-mediated relaxations of the aortae and L-NOARG abolished an enhancement by acute hyperthyroidism of muscarinic receptor-mediated relaxation, suggesting that the effects may be due to an alteration in muscarinic receptor-mediated NO systems of the aortae at early stage of hyperthyroidism.

Acetylcholine↗
PubMed2003

Normalization of low biotinidase activity in a child with biotin deficiency after biotin supplementation.

We report findings in a Japanese boy with severe skin rash attributable to biotin deficiency. The patient had an intracranial malformation and developed biotin deficiency due to tube feeding with a single formula for over one year. Results of urinary organic acid analysis were consistent with multiple carboxylase deficiency, and low biotinidase activity was also observed. After biotin supplementation, the skin rash improved and biotinidase activity normalized. We speculate that biotin is one regulating factor in the biosynthesis of biotinidase.

Biotin↗
PubMed2001

A study of quality assessment in clinical microbiology performance of independent laboratories in Tokyo: 18-year participation in the Tokyo Metropolitan Government External Quality Assessment Program.

We evaluated the performance of independent microbiology laboratories in Tokyo over an 18-year period of participation in the external quality assessment (EQA) program, and we estimated the impact of the EQA program. The study design was a longitudinal retrospective analysis of performance, including isolation, identification, and antimicrobial susceptibility testing of bacteria from simulated patients' samples, in "open" surveys compared with "blind" surveys. Independent microbiology laboratories, licensed by the Tokyo Metropolitan Government, have been subject to mandatory evaluation by the EQA program since 1982. Survey reports, correspondence, annual guidance meetings, and inspections are used as quality improvement strategies. The performance for identification in "blind" surveys was significantly worse than that in "open" surveys (P < 0.001). Poorly performing laboratories had common features, including inadequate supervision by physicians and lack of familiarity with the impact of variations on the use of the standards. However, there were improvements in the performance of identification of some pathogens. The performance of susceptibility testing has not yet reached the relatively high level seen for identification. Some of the smaller laboratories have been gradually acquired by commercial chains operating outside Tokyo. The EQA program has established a role both in regard to laboratory improvement and as an educational tool. However, the program lags behind these of other developed countries in regard to the practical sciences. The main problems in regard to laboratory improvements are a shortage of human resources in clinical microbiology, lack of standardization of laboratory methods, and the pressures of financial constraints in the Japanese medical insurance system.

Data Collection↗
PubMed2001

Survey of antibiotic resistance in Pseudomonas aeruginosa by The Tokyo Johoku Association of Pseudomonas Studies.

Pseudomonas aeruginosa resistance (minimum inhibitory concentration [MIC], > or =16 microg/ml defined as resistant) to meropenem, imipenem, panipenem, piperacillin, ceftazidime, cefozopran, cefoperazone, sulbactam/cefoperazone, amikacin, and tobramycin, as well as cross-resistance profiles, were investigated in P. aeruginosa strains isolated at eight hospitals in the Johoku area, Tokyo, during November 1998. Overall, 8.3% of isolates were imipenem-resistant and 4.6% were ceftazidime-resistant. However, the incidence of antibiotic-resistant P. aeruginosa was distinctly different at each hospital. P. aeruginosa resistance to imipenem ranged from (MIC) 1 to 64 microg/ml (MIC90 32 microg/ml), and its resistance to ceftazidime ranged from 2 to more than 128 microg/ml (MIC90, 64 microg/ml). Meropenem (MIC range, < or =0.25 to 16 microg/ml) was more active than panipenem (MIC range, 2 to 64 microg/ml). Cefozopran was more active than piperacillin, cefoperazone, or sulbactam/cefoperazone, but many strains were resistant to cefoperazone (17/57). Our analysis found cross-resistance to many beta-lactams, but the degree of cross-resistance was very variable.

Anti-Bacterial Agents↗
PubMed2001

A new quantitative analytical method of serum biotinidase activity using biocytin as a substrate and its clinical significance in Japan.

We have developed a new quantitative analytical method of serum biotinidase activity, which uses the native substrate biocytin, and to which can be applied the improved agar plate method of biotin bioassay. Assay characteristics were within acceptable ranges (intra-assay CVs, 4.44% and 1.95% at 1.82+/-0.08 and 3.08+/-0.06 pmol/min/ml; day-to-day CV, 5.92% at 2.68+/-0.16 pmol/min/ml). The enzyme activity with biocytin was stable at 4 degrees C for 90 days. The mean value of the serum biotinidase levels in 129 healthy adults was 2.71+/-0.93 pmol/min/ml. The method was clinically comparable with a colorimetric method for detection of biotinidase deficiency. Biotin supplementation treatment normalized our partial biotinidase deficiency patient's serum biotinidase activity. This normalized phenomenon has not yet been observed in a Caucasian patient. We also found that the distribution of the enzyme activities with biotinyl-p-aminobenzoate in 8 of 11 patients with suspected biotin metabolic disorders shifted to a higher level than that of the controls. Although, we have few opportunities to analyze the sera of biotin metabolic disorders in Japan, the new method are suitable for clinical research applications in combination with the colorimetric method.

Adult↗
PubMed2001

[The relationship of serum mitochondrial creatine kinase and rotavirus gastroenteritis in pediatric patients].

The objective of this study was to investigate the relationship between serum mitochondrial creatine kinase(mCK) and rotavirus gastroenteritis in pediatric patients. Stool and serum specimens were simultaneously collected from 45 patients(25 males and 20 females) with suspected rotavirus gastroenteritis from January to December 1998. Stool specimens were tested by rotavirus latex agglutination assay. Fourteen patients(10 males, 4 females) were proved as positive, and peak season was in winter and early spring(7 positive cases in March). Six of the 14 were younger than one and 7 were between one and two. Total serum CK activity was measured by The Japan Society of Clinical Chemistry (JSCC) recommended method, and mCK activity was calculated from mCK fraction % obtained by CK isoenzyme electrophoresis. Patients' mCK activities were as follows, rotavirus antigen positive patients(n = 14): 60.0 +/- 20.6 U/l and rotavirus antigen negative patients(n = 31): 7.2 +/- 5.5 U/l. Significant difference was observed between rotavirus antigen positive group and rotavirus antigen negative group(p < 0.01), and control children group(n = 105): 7.1 +/- 2.9 U/l, (p < 0.01). The clinical implications and mechanisms of increased serum mCK activity are unclear. It is known that histological study of the small intestine from rotavirus gastroenteritis patients reveal shortened villi and mononuclear cell infiltration of the lamia propria; electron microscopy shows mitochondrial swelling and sparse irregular microvilli. Elevated serum mCK level of rotavirus gastroenteritis patient may therefore reflect diffused intestinal epithelial cell damage.

Child, Preschool↗
PubMed2001

Survey of veterinary professionals for antibodies to Bartonella henselae in Japan.

The seroprevalence of Bartonella henselae among veterinary professionals in Japan was investigated by means of an immunoperoxidase (IP) test that used protein A-horseradish peroxidase conjugate. Sera were obtained from 233 veterinary professionals in the Tokyo and Chiba areas. As negative control group, sera from 155 healthy individuals (all medical students) were used. As positive control group, sera from 5 patients highly suspected of cat scratch disease (CSD) by clinical symptoms were tested. Serum antibody titers of > or = 200 to B. henselae were presumed seropositive, because the titer at which about 95.5% of all healthy individuals (148 of the 155) were negative, and 2 of the 5 suspected CSD patients' serum antibody titers were > or = 200. Of the individuals in the veterinary professionals group tested, 35 of the 233 (15.0%) were seropositive for B. henselae. Females were nearly twice as likely as males to have antibodies to B. henselae in the veterinary professionals group. Our data suggest that Japanese veterinary professionals, and in particular younger females who are veterinary assistants and animal beauticians are more often infected by B. henselae.

Adolescent↗
PubMed2001

[A study of serum mitochondrial enzymes(mCK, mAST, mMDH) in rotavirus and adenovirus gastroenteritis in pediatric patients].

Rotavirus and adenovirus antigens in feces from 77 cases of gastroenteritis in pediatric patients were examined. Mitochondrial enzymes, mitochondrial creatine kinase(mCK), mitochondrial aspartate amino-transferase(mAST) and mitochondrial malate dehydrogenase(mMDH) activities in their sera were also measured and compared with the results of rotavirus and adenovirus antigens in the feces. Thirty-one cases were rotavirus antigen-negative(rota-negative)/adenovirus antigen-negative(adeno-negative), 5 were rota-negative/adenovirus antigen-positive(adeno-positive), 40 were rotavirus antigen-positive(rota-positive)/adeno-negative, and only one case showed positive for both antigens. The mean activities of these three enzymes were compared among 3 groups except one both positive case mentioned above and control group(n = 105) by Mann-Whitney U-test. The serum mCK activity was significantly higher in rota-positive/adeno-negative patients than in other groups(p < 0.01). On the other hand, no significant differences were observed for mAST and mMDH activities among any groups. It is suggested that these phenomena are caused by the differences of localization of these enzymes in mitochondria, that mCK is located the outer surface of inner membrane of mitochondria, and mAST and mMDH are located on the inner surface. The difference of serum mCK activity between rotavirus infection and adenovirus infection suggests that intestinal epithelial cell injury by rotavirus is stronger than that by adenovirus.

Adenoviridae Infections↗
PubMed2001

[Choosing effective laboratory tests for diabetes care, and the reimbursement system].

Diabetes mellitus is a prototype chronic disease. The number of patients with diabetes in Japan is estimated to be about 6.9 million. Expenditure for diabetes care is increasing rapidly and this increase imposes a major economic burden. The Japanese Government has developed health-care payment policies designed to balance the growth of health-care expenditure against other national priorities. Often these policies tend to limit the various services. The Japan Diabetes Society(JDS) published management guidelines for diabetes for general practitioners in 1999. There is increasing concern about the cost of laboratory studies, including self-monitoring blood glucose(SMBG), as well as the cost of general diabetes care. The Japanese Society of Laboratory Medicine(JSLM) has also developed standards to choose effective laboratory tests for general practitioners. Health professionals must have a clear knowledge of the reimbursement system in order to understand the economic factors that control the services available to their patients. Ideally, however, the reimbursement system should meet the financial needs of the services necessary to conform to the professional consensus of the acceptable quality of care for people with diabetes.

Blood Glucose Self-Monitoring↗
PubMed2000

[Proceeding of the workshop "What an ideal clinical microbiological laboratory should be". The 33rd in-service training course for medical technologists of university hospitals in 1999].

In the workshop of the 33rd in-service training course for University Hospital Medical Technologists in 1999(sponsorship: the ministry of Education), all groups of participants were charged with discussing an ideal clinical microbiology laboratory. In conclusion, the successful operation of the ideal system of clinical microbiology should require a high level of competence in every staff member of the hospital. It must not be focused solely on the sophistication of laboratory methods. We must modify our behavior effectively and establish a good collaborative partnership with physicians and other health care professionals.

Clinical Laboratory Techniques↗
PubMed2000

[Changes in the antibacterial activity of chemotherapeutic agents (especially carbapenems) for 10 species of clinical isolates between 1994 and 1996. Surveillance group of the sensitivities of clinical isolates to antibacterial agents].

During October and December of each year of from 1994 to 1996, 3,849 strains of 10 species of bacteria were isolated from clinical materials in 21 institutions nationwide. The minimum inhibitory concentrations (MICs) for these bacteria of four carbapenems (imipenem [IPM], panipenem [PAPM], meropenem [MEPM], and biapenem [BIPM]) and other representative antibacterial agents were measured to investigate annual changes in antibacterial activity. Carbapenems showed potent activity against methicillin-sensitive S. aureus (MSSA), S. pneumoniae, E. faecalis, H. influenzae, E. coli, K. pneumoniae, E. cloacae, S. marcescens, and the B. fragilis group, with the activity being stable. However, these drugs showed weak activity against methicillin-resistant S. aureus (MRSA) and P. aeruginosa. The antibacterial activity (MIC90) against the tested organisms generally remained stable. Particularly, there was annual improvement of the MIC90 values of IPM and BIPM for S. pneumoniae, as well as the values of IPM and PAPM for H. influenzae, and those of IPM, PAPM, and BIPM for S. marcescens. On the other hand, the activity of carbapenems (including IPM) against MRSA was not necessarily strong, but there was annual improvement of MIC90 values.

Bacteria↗
PubMed2000

A study on task-analysis of clinical pathologists as medical consultants in Nihon University Hospital--a Japanese perspective by comparison with current status in the USA.

To identify our role and the customers' satisfaction, the on-call consultation service records of the Department of Clinical Pathology, Nihon University School of Medicine, Itabashi Hospital (NUIH), were analyzed. Between 1995 and 1998, 1,789 consultation services were recorded, and approximately 40% were from physicians, and 50% were from medical technologists. During office hours, many physicians made contact with us at the office of clinical pathology, the clinical laboratory and other places in the hospital by various means. They asked us to interpret multidisciplinary laboratory data, and to provide the specific information that might affect clinical management. Medical technologists asked for clinical information of patients with extreme measured values and requested that we contact with physicians. In contrast, on weekends/holidays or after routine working hours, physicians sometimes requested non-automated laboratory tests such as peripheral blood smears/bone marrow smears or Gram stains. The major contents of our responses to medical technologists were concerned with blood banking and handling of instruments not to be operated in routine work. These results reconfirm that we are still required to have clinical competence for common laboratory procedures and to have the capability of interpretation of multidisciplinary laboratory data in the university hospital. Traditionally, most Japanese clinical pathologists have been focused their attention on bench work in research laboratories. However, the present study shows that the clinical pathologists need to bridge the real gap between laboratory technology and patient care. Our on-call service system can enhance the education of clinical pathologists, and improve not only laboratory quality assurance but also patient care. In addition, in response to a need for customer access to this service with a shortage of clinical pathologists, a more effective method would be to set up a proactive systemic approach in a more rigorous academic environment adopting advances in medical informatics.

Consultants↗
PubMed2000

[What should a laboratory physician expect from a microbiology laboratory?].

Remarkable changes are affecting the discipline of Clinical Pathology/Laboratory Medicine in Japan. Laboratories are changing from revenue centers to cost centers that have many serious problems(ex. closure of the clinical laboratories in the hospitals and outsourcing of laboratory tests due to restructuring in response to economic aspect, limited numbers of certified laboratory physicians, and other factors). And many clinicians in university hospitals do not know what they should expect correctly from the microbiology laboratory. Therefore, we, laboratory physicians and medical technologists must modify our behavior effectively and establish a good collaborative partnership with physicians, nurses and other health care professionals. The microbiology laboratory should provide information that will affect clinical management guidelines for obtaining specimens, microbial identification, antimicrobial susceptibilities, reporting of data and educational updating. Leadership and management skills must be increasingly critical to the success of laboratory physicians in and outside of academic centers.

Certification↗
PubMed1999

[Two cases of pasteurellosis accompanied by exudate with semen-like odor from the wound].

We encountered two cases of Pasteurella multocida subsp. septica isolation from exudates with seminal fluid-like odor from dog scratch and cat bite. Case 1: A 78-year-old male who had been diagnosed as having diabetes mellitus five years ago was scratched by the claw of a pet dog (Pekinese) on the back of the right hand. Since inflammation ascended to the arm, the patient visited Nihon University Itabashi hospital for a medical examination. Case 2: A 51-year-old female without a specific past history other than hyperlipidemia was bitten by a pet cat at the medical and lateral sides of the left carpus. The patient immediately opened the wound and washed it with tap water, followed by disinfection using a non-iodine disinfectant at home. Two hours later, the patient felt an unpleasant sensation and smelled a seminal fluid-like odor at the wound. The next morning, the entire left arm swelled and pain worsened, then the patient sought medical attention. The patients were treated with antibiotics and the wound completely healed on the 16 days from on set in Case 1 and on the 10 days from onset in Case 2. From these two cases, Pasteurella multocida subsp. septica was isolated from the exudate, suggesting that when wounds caused by animals smell like seminal fluid, the wound is infected with Pasteurellae. This finding may be an important clue for differentiation in clinical diagnosis.

Aged↗
PubMed1999

The expression of granulocyte-macrophage colony-stimulating factor (GM-CSF) and its regulation by ovarian steroids in rat uterine stromal cells.

The effects of ovarian steroids on the expression of granulocyte-macrophage colony-stimulating factor (GM-CSF) in rat uterus were examined. Intense expression of GM-CSF mRNA was dispersedly located in the endometrial-myometrial junction and stroma of the uterus. GM-CSF was immunohistochemically localized in stromal cells and luminal epithelium. Ovariectomy significantly reduced the appearance of GM-CSF-mRNA-positive cells and the levels of expression for GM-CSF mRNA in the whole uterus, whereas treatment with 17beta-estradiol (E2) or a combination of E2 and progesterone (P4) for 5 days on ovariectomized animals recruited GM-CSF-mRNA-positive cells and stimulated its expression. The combined treatment with E2 and P4 also stimulates the expression for GM-CSF mRNA and the production of immunoreactive GM-CSF in the stromal tissues. These data suggest that the expression of GM-CSF in uterine stromal cells is partially regulated by ovarian steroids.

Animals↗