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Biomedical subjects

K Koga

Publications and source records attributed to K Koga.

At least 199 records · Page 11Linked to original sources
PubMed1991

[Studies on tsutsugamushi disease in Gifu prefecture. 4. Survey results in Ena and Takayama City, and the summary of the studies in the prefecture].

Investigations of trombiculid mites and Rickettsia tsutsugamushi in wild rodents were made in Ena (Nov. 1988) and Takayama (May 1989) City. In the former area where no patient has been reported so far, Leptotrombidium pallidum (63.9%) was most predominant and no L. scutellare was found. A Karp-related rickettsia (11.1%) was isolated from wild rodents and 30% of them had antibody to R. tsutsugamushi (anti-Karp was prominent). The latter area where patients were reported in spring as well as in autumn, L. pallidum (22.4%) was one of the dominant species in spring. Karp-related strains were isolated from 37.5% of wild rodents. And the antibody possession rate was 50.0%. These data reconfirmed our hypothesis that the majority of patients in autumn were infected by L. scutellare and a part by L. pallidum. In spring in Takayama area, the vector was L. pallidum which possessed Karp-related strain(s).

Animals↗
PubMed1991

[A case report of a patient repeatedly infected with Ancylostoma duodenale, probably from himself through his artificial anus, and resistant against a single dose of pyrantel pamoate].

A 88 year old Japanese male was repeatedly infected with Ancyclostoma duodenale. He underwent an artificial anus operation about 55 years ago. He appeared to be infected with hookworm earlier than in 1977 and developed severe anemia. Though he was treated with pyrantel pamoate and mebendazole several times, reinfections developed in each time. A possible origin for his reinfections was his own feces defecated through his artificial anus. Unsanitary handling of the anus and the feces exposed himself to oral or percutaneous infection. Besides, a single dose of pyrantel pamoate, usually very effective against Ancylostoma duodenale, was not so effective in this patient. Therefore, we prescribed multiple doses of pyrantel pamoate, and followed by a single dose of mebendazole. However, reinfections still persisted because of his unsanitary behavior.

Aged↗
PubMed1991

Muscle sympathetic nerve responsiveness to static contraction is not altered under hypoxia.

The purpose of this study was to determine if response in muscle sympathetic nerve activity (MSNA) to static muscle contraction alters or not during peripheral chemoreceptor stimulation with hypoxia. MSNA was recorded from the tibial nerve using a microneurographic technique in seven healthy subjects in a sitting position. They performed a static handgrip exercise (SHG) for 2 min under normobaric normoxia and hypobaric hypoxic conditions corresponding to an altitude of 4,000 m (460 mmHg). MSNA represented as burst rate and total sympathetic nerve activity (TSNA) (burst rate X mean burst amplitude) at rest increased by 7.7 bursts/min and by 60%, respectively, compared to those under normoxia. During the exercise, MSNA increased over control values before exercise both under normoxia and hypoxia. TSNA increased during the first and second minute of SHG by 19% (p greater than 0.05) and 35% (p less than 0.05) in normoxia and by 15 (p greater than 0.05) and 34% (p less than 0.05) in hypoxia over the control value, respectively, while the absolute intensity of MSNA during SHG was higher under hypoxia. The response of MSNA to SHG which showed algebraic sums was the same under normoxia and hypoxia, that might relate to consist of afferent pathways independent from carotid chemoreflex.

Adult↗
PubMed1991

[Bilateral acute profound deafness after MMR vaccination--report of a case].

In April 1989 the MMR vaccination program had started, and until October, 1989, 630,000 children received vaccination. In is, however, well known that many children developed various complication including aseptic meningitis after vaccination, and the MMR vaccination program has discontinued. This report described a case of bilateral acute profound deafness most likely due to MMR vaccination. The cause of this deafness was presumed to be mumps vaccination. The bases of the presumption are as follows: the meningitis after MMR vaccination was elicited by PCR method to be caused by mumps vaccine, and the complication of CNS after measles vaccination occurs within 14 days after injection, while the onset of vomiting and gait disturbance of the case was 24 days after vaccination.

Acute Disease↗
PubMed1991

A modified agar plate method for detection of Strongyloides stercoralis.

The agar plate method is a new technique with high detection rates for coprological diagnosis of human strongyloidiasis. This report details modifications of the technique and establishes a standardized procedure. We recommend that all plates should be carefully observed using a microscope because macroscopic observation can lead to false negative results. It is also advisable to pour formalin solution directly into microscopically positive dishes to collect worms by sedimentation. This procedure enables one to observe worms otherwise hidden. Sealing dishes with adhesive tape prevents larvae from crawling out of the dishes, eliminating any possibility in the reduction of detection rates, and greatly improves the safety conditions for the technician performing the procedure. We consider the agar plate method to be superior to the filter paper method in detecting Strongyloides, and we believe that it will eventually become the technique of choice.

Animals↗
PubMed1991

Purification and characterization of beta-N-acetylhexosaminidase from Trichoderma harzianum.

beta-N-Acetylhexosaminidase was produced by Trichoderma harzianum cultivated with chitin as the growth substrate. The enzyme was purified 13.2-fold to homogeneity by ultrafiltration and sequential chromatography on SP-Toyopearl and Sephacryl S-200. The molecular weight of the enzyme was estimated to be about 150,000 by gel filtration. The pH and temperature optima were 4.0-5.5 and 50 degrees C, respectively. The enzyme hydrolyzed N-acetylchitooligosaccharides at the non-reducing ends to release GlcNAc monomer. The enzyme showed a strict substrate specificity to the sugar chains in complex carbohydrates, hydrolyzing only the linkage of GlcNAc beta 1-3Gal, but not hydrolyzing the other linkages such as GalNAc beta 1-3Gal and GlcNAc beta 1-2Man.

Acetylgalactosamine↗
PubMed1991

[In-vivo 19F-MRS study of 5-fluorouracil (5-FU) metabolism on tumors].

5-Fluorouracil (5-FU) metabolism on tumors was studied by in-vivo 19F-MRS (magnetic resonance spectroscopy). In this study, two kinds of tumors were used, i.e., Yoshida sarcoma implanted subcutaneously to the abdomen of rats and drug-induced tumors in the rats livers. Sequential 19F spectra were obtained just after 150 mg/kg 5-FU injected intravenously. In Yoshida sarcoma, the accumulation of 5-FU was observed and disappearance of 5-FU was slower compared to the normal tissue. However, synthesis of fluoronucleotides (Fnct) could not be detected. In drug-induced liver tumors, the peak of fluoro-beta-alanine (FBAL) was observed. Disappearance of 5-FU and catabolism to FBAL in the liver tumors group were slower compared to the normal liver. Synthesis of Fnct did not increase in the liver tumor group. The results in the liver tumor group are considered to be the confined result of the hepatocytes and tumors cells. It was considered that the delayed catabolism to FBAL in the liver tumor group showed metabolic dysfunction of the liver. Also the synthesis of Fnct in tumors could not be detected by in-vivo 19F-MRS. 19F-MRS method could not detect Fnct in tumors in-vivo. However, the accumulation of 5-FU could be assessed by this method. It is expected that the evaluation of 5-FU pooling in tumors could be used for the index of chemotherapeutic effect.

Animals↗
PubMed1991

[Measurement of enzyme activity of control materials containing human enzymes by IFCC reference methods].

In order to unify interlaboratory clinical enzyme data, a reference method and reference material are necessary for each enzyme. Although reference methods recommended by various societies of clinical chemistry including JSCC are now available for some routinely measured clinical enzymes, the availability of secondary enzyme references or calibrators, limits the practical application of standardization concept for minimizing present interlaboratory variation of enzyme data. Since control sera prepared by adding enzymes from human cell cultures to a pool of human serum may meet the requirements as candidates for such reference materials, we attempted to assign values to 6 enzymes present in the materials by mainly the IFCC reference methods following the procedures as strictly as possible and yet with modifications where necessary. This paper describes each step of the value assignment for accuracy control purposes.

Alkaline Phosphatase↗
PubMed1990

[Index of tumor response by in-vivo 31P-MRS--T1 effect as a new predicting index of therapeutic effects].

We observed the metabolism of the Yoshida sarcoma by in-vivo 31P-MRS, using two varieties of repetition time (TR), i.e., TR2s and TR10s. It was measured before the injection of 5FU and 4, 24, 48 hours after the injection. In the each time, PME/ATP ratio, intracellular pH, and TR10/TR2 ratio of PME which reflects the T1 value of PME, were calculated. TR10/TR2 ratio of PME decreased 4 and 24 hours after the injection of 5FU and recovered 48 hours after the injection to the same level before the injection. However decrease of PME/ATP ratio was not observed until 48 hours after the injection of 5FU, when apparent tumor regression appeared. These results suggested that the T1 value of PME decreased prior to the PME changes and when the PME decreased, the intracellular environment of PME recovered to the same state before the therapy. It was considered that the TR10/TR2 ratio of PME offers significant information different from the PME/ATP ratio. It is possible to use the TR10/TR2 ratio as a predicting index for the therapeutic effects.

Animals↗
PubMed1990

Characteristic differences in the lipid composition of middle ear effusions in adult and pediatric patients: phosphatidylethanolamine and phosphatidylserine levels.

Middle ear effusions (MEEs) from adult patients with otitis media with effusion are usually serous in nature, but those from pediatric patients younger than 8 years old are frequently mucous in consistency. MEEs contain substances secreted by the epithelial cells of the middle ear and eustachian tube to regulate surface tensions as well as those produced as the result of inflammation. Since the biochemical bases of serous and mucous MEEs have not been clearly established, we analyzed all lipid components of MEEs from seven children and seven adults by thin-layer and gas-liquid chromatography, and also compared them with those from sera. Although no significant difference in the lipid composition was observed between adult and pediatric sera, the relative concentration of phosphatidylethanolamine (PE) in the pediatric MEEs was 26.5%, while that in the adult MEEs was 9.2% and was significantly different. A similar high concentration of phosphatidylserine (PS) was also observed in the pediatric MEE. Since phospholipids are major components of surfactants secreted from the epithelial cells of the middle ear, significantly high concentrations of both PE and PS as charged phospholipids may be responsible in part for the mucoid characteristics seen in pediatric MEEs.

Adult↗
PubMed1990

Lethal efficacy of extract from Zingiber officinale (traditional Chinese medicine) or [6]-shogaol and [6]-gingerol in Anisakis larvae in vitro.

The authors previously reported that an extract from Zingiber officinale, traditionally eaten along with raw fish and used in traditional Chinese medicine, effectively destroyed Anisakis larvae in vitro. In this study, we analyzed the effective components of ginger rhizomes. Methanol extracts were fractionated after first being treated with HCl at pH 3, then with NaHCO3 at pH 10, and, finally, with NaOH at pH 13 (fraction 1). In general, this fraction is rich in neutral substances. [6]-Shogaol and [6]-gingerol, known neutral components of ginger rhizomes, were detected using gas chromatography and were found to be the most prevalent components in the fraction, occurring in quantities that resulted in a dose-dependent killing efficacy. Authentic [6]-shogaol and [6]-gingerol could kill Anisakis larvae at a minimal effective dose of 62.5 and 250 micrograms/ml, respectively. However, the concentration of [6]-gingerol in fraction 1 was greater than 20 times that of [6]-shogaol, making the former the most active component in the fraction. Furthermore, synergistic effects between [6]-gingerol and a small amount of [6]-shogaol were observed. Pyrantel pamoate, an available antinematodal drug, had no lethal effect, even at a concentration of 1 mg/ml. In saline solution containing [6]-shogaol (62.5 micrograms/ml), greater than 90% of larvae lost spontaneous movement within 4 h and were destroyed completely within 16 h. Microscopical examinations showed destruction of the digestive tract and disturbances of culticulae.

Animals↗
PubMed1990

Acid triacyglycerol lipase inhibitor in chicken plasma: purification and properties.

1. Acid triacylglycerol lipase inhibitor was highly purified from chicken plasma by ammonium sulfate fractionation (0.6-1 saturation) followed by successive chromatographies on Hydroxyapatite, Blue-Cellulofine, Phenyl-Sepharose and Cellulofine GCL-2000 columns, and isoelectric focusing. 2. The lipase inhibitor showed its inhibitory action on triacylglycerol lipases in chicken erythrocytes ghosts and in chicken liver lysosome, but did not on pancreatic lipase, Rhizopus arrhizus lipase, or wheat germ lipase. 3. The inhibitor showed its molecular weight of 32,000 by Cellulofine GCL-2000 gel filtration. The inhibitor showed some heterogeneity on isoelectric focusing, and the main band had a pI of 5.10. 4. The lipase inhibitor did not show any inhibitory action on trypsin or chymotrypsin.

Ammonium Sulfate↗
PubMed1990

Otitis media with effusion associated with Chlamydia trachomatis infection in children.

In an attempt to discover the role of Chlamydia trachomatis in the pathogenesis of middle ear diseases, we examined middle ear effusions (MEEs) from 69 patients with otitis media with effusion (OME) for the presence of C. trachomatis and antibodies to the organism. Age distribution was 1 to 14 years (mean age 6.1 years). C. trachomatis was isolated by the culture method from MEE of 11 of 31 (35.5%) patients and from 2 of 5 (40.0%) nasopharyngeal specimens. Chlamydial antigen, however, was found in 29 MEEs from 57 patients (50.9%) using an immunofluorescent method (Syva, 'MicroTrak'). Antibodies to the agent were found in 23 MEEs of 40 patients (57.5%) using the Micro-IF test. Antigen and antibodies were determined at the same time and both were detected in 20 of 40 (50.0%) patients. Although the isolation rate for C. trachomatis from MEE was low, antigen and antibodies were detected in 50.0% of patients with OME. These results suggest the possibility that immune complexes are formed with C. trachomatis in the middle ear, and that these immune complexes cause the mucosal damage responsible for chronic middle ear mucosal irritation.

Adolescent↗
PubMed1990

Stereoselective reactions. XVIII. Synthesis and cytotoxicity of the demethyl derivatives of steganes.

Demethyl derivatives of steganes and deoxypodorhizon, 3, 4, 6, 7, 9, 10, 12, 13, 18, 23, were prepared by the selective demethylation of the methoxy group of steganes and deoxypodorhizon, 2, 5, 8, 11, 22. The cytotoxicity of these derivatives was evaluated against KB cell and was found not to exceed that of the parent steganes. 4-Demethyldeoxypodorhizon (18) was found to show more potent cytotoxicity than deoxypodorhizon.

4-Butyrolactone↗
PubMed1990

[Effect of midazolam as a premedicant].

A new benzodiazepine-type drug, midazolam, was administered intramuscularly as a premedicant to 155 patients aged from 16 to 81 years with ASA status 1 or 2. The hypnotic action and the effect on the upper airway tract of midazolam were evaluated. Hypnosis appeared 5 minutes after the administration of midazolam, reached its plateau after 20 minutes and started to decline after 30 minutes. The hypnotic effect showed dose-dependent increase in doses ranging from 0.05 to 0.20 mg.kg-1. No age-dependent differences in hypnosis were observed except for teenage group which showed stronger hypnosis than the other age groups. There was no problem on the upper airway tract for all age groups at the dosage of 0.05 mg.kg-1, but in the patients over 40 years increasing dosage tended to obstruct the upper airway tract. Along with the appearance of hypnosis, cough and breath holding, suggesting retention and aspiration of saliva, were observed. The appropriate dosage of midazolam for premedication was considered to be 0.05 mg.kg-1.

Adolescent↗
PubMed1990

[Radiotherapy combined with cis-diammine-dichloro platinum (II) plus vindesine in the treatment of non-small cell lung cancer: a comparison with treatment by radiation alone].

The effect of CDDP + VDS has been evaluated in 39 cases of non-small cell lung cancer, compared with those treated with radiation alone. Nineteen cases consisted of a combined radiation and chemotherapy group, while twenty cases were classed a the radiation therapy only group. CDDP was given at a dosage of 60 to 110 mg/m2 every 4 weeks, and VDS at a dosage of 3 mg/m2 3 times weekly. Radiation was given at a fraction dose of 1.5 to 2 Gy 5 times per week with a mean total dose of 56 Gy in the radiation only group, and 50 Gy in the combined therapy group. There were no significant difference in both the response rate and the survival time between the two groups. This suggests that combined chemotherapy was not effective for the treatment of non-small cell lung cancer.

Aged↗
PubMed1990

[Interstitial pneumonia developed after combination chemotherapy with (CDDP, VDS, MMC) and radiotherapy].

Reported is a case of interstitial pneumonia that developed after CDDP, VDS, and MMC combination chemotherapy and radiotherapy. The patient, a 68-year-old male, had received chemotherapy three times, beginning with CDDP + VDS, followed by CDDP, VDS, and MMC, in that sequence, after which he was given radiotherapy. The interstitial pneumonia developed one day after a dose of 54 Gy. It is felt that MMC played the leading role and the radiation the inducing role in the development of his interstitial pneumonia.

Aged↗