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Biomedical subjects

K Harada

Publications and source records attributed to K Harada.

At least 991 records · Page 55Linked to original sources

Improvement of chemical analysis of antibiotics. IX. A simple method for residual tetracyclines analysis in honey using a tandem cartridge clean-up system.

A simple, rapid and precise analytical method for the residual tetracyclines in honey has been established using a tandem cartridge clean-up system (prepacked reversed-phase and ion-exchange cartridges) followed by high-performance liquid chromatography. The recoveries of oxytetracycline (OTC), tetracycline (TC), chlortetracycline (CTC) and doxycycline (DC) from honey spiked at a level of 1.0 ppm are 87.1, 85.3, 98.0 and 99.0%, respectively, with coefficients of variation of 1.1-3.9%. The detection limits in honey are 0.02 ppm for OTC and TC, and 0.05 ppm for CTC and DC, respectively. The time required for the analysis of four samples is only 1 h.

Anti-Bacterial Agents↗

Establishment of hybridoma secreting human monoclonal antibody against hepatitis B virus surface antigen.

The HAT (hypoxanthine, aminopterin, thymidine) sensitive and ouabain resistant human B lymphoblastoid cell line TAW-925 was obtained from 6-thioguanine resistant B lymphoblastoid cell line WI-L2. Hybridomas were obtained at a high frequency (10(-4)-10(-5) when TAW-925 was hybridized with cells transformed with Epstein-Barr virus. Using TAW-925 as a parental cell line, we have obtained a hybridoma which stably secretes human monoclonal antibody against hepatitis B virus surface antigen.

Antibodies, Monoclonal↗

Rare neonatal intracerebral hemorrhage. Two cases in full-term infants.

Intracranial hemorrhage in neonates is often found in either the subependymal area or the subdural space. The former is observed particularly in premature infants and is attributable to damage of the germinal matrix layer. The latter usually occurs in the vicinity of the falx and tentorium cerebri of full-term neonates and is thought to be caused by birth injury. Two cases of intracerebral hemorrhage in full-term newborn babies are reported. In both the hematoma was located at the left frontal area under the coronal suture. Angiograms revealed no causative signs, such as arteriovenous malformation, aneurysm or angioma. Observations on CT scans and during surgery led to the conclusion that the hemorrhages were caused by the moulding which forced the frontal bone to slip under the parietal bone at the coronal suture and then press on the fragile cerebral vasculature of the neonates, thus causing contusion.

Brain Concussion↗

Changes in proton T1 in dog brains due to the administration of haloperidol.

Changes in proton T1 in dog brains due to the administration of haloperidol were determined by the intravenous administration of a single dose of 20 mg of haloperidol to mongrel dogs. The MRI used was the Aberdeen type with the static magnetic field of 0.1 T. A coil made exclusively for these animals (bore diameter 120 mm) was used. There was a significant increase in the T1 value in the striate body 30 minutes and more (within two hours) after the administration of haloperidol. Subtraction images were also obtained by subtracting the image of the pre-treatment (control) T1 values from the image of the post-treatment values (2 hours after the injection). The subtraction images also revealed increases in the T1 values of the striate body.

Animals↗

Clinical evaluation of basic fetoprotein in testicular cancer.

We attempted to determine the efficacy of basic fetoprotein as a marker in testicular cancer. The levels of serum basic fetoprotein were studied in 58 patients (31 with seminoma and 27 with nonseminoma). Elevated levels were observed in 22 seminoma (71 per cent) and 15 nonseminoma (56 per cent) patients, while the levels of other markers (beta-subunit of human chorionic gonadotropin, alpha-fetoprotein and lactic dehydrogenase) remained normal in 6 seminoma (19 per cent) and 2 nonseminoma (7 per cent) patients. The levels of basic fetoprotein changed in relation to the clinical courses and they elevated again in 3 of 4 patients with recurrence. The concentration of basic fetoprotein in testicular cancer tissue was significantly higher than in the normal testis. Histological localization of basic fetoprotein in testicular cancer tissue was demonstrated immunohistochemically. Thus, basic fetoprotein was considered to be a useful serum marker for testicular cancer.

Antigens, Neoplasm↗

Nucleosides. 139. Synthesis and anticytomegalovirus and antiherpes simplex virus activity of 5'-modified analogues of 2'-fluoroarabinosylpyrimidine nucleosides.

In order to determine if modification of the 5'-position reduces or abolishes the antiviral activity of 2'-fluoro-5-iodo-ara-C (FIAC), 2'-fluoro-5-iodo-ara-U (FIAU), or 2'-fluoro-5-methyl-ara-U (FMAU) against human cytomegalovirus (HCMV) and herpes simplex virus (HSV), the 5'-deoxy, 5'-mercapto, and 5'-amino analogues of these nucleosides were prepared. 5'-Deoxy-FIAC and 5'-deoxy-FIAU were prepared by catalytic hydrogenation of 5'-iodo-FIAC and 5'-iodo-FIAU to 5'-deoxy-FAC and 5'-deoxy-FAU, respectively, followed by reiodination at C-5. Reduction of 5'-iodo-FMAU afforded 5'-deoxy-FMAU. These 5'-deoxy nucleosides were found to be inactive against HCMV, indicating that the conversion to 5'-phosphate by the cellular enzyme(s) is a requirement for antiviral activity against this virus. Other 5'-modified (NH2 and SH) analogues were also prepared from 5'-O-tosyl-FIAC and 5'-O-tosyl-FMAU. Treatment of these tosylates with LiN3 in DMF afforded the corresponding 5'-N3 products. Catalytic hydrogenation of 5'-N3-FMAU afforded 5'-NH2-FMAU, whereas 5'-NH2-FIAC was obtained by treatment of 5'-N3-FIAC with Ph3P in pyridine. 5'-Mercapto analogues were prepared by treatment of 5'-O-tosyl-3'-O-acetyl nucleosides with KSAc followed by deacetylation. 5'-NH2-FMAU was the only compound that showed good activity against HSV-1 and HSV-2 in vitro. However, this compound was less potent and had a lower therapeutic index than FMAU.

Animals↗

Electron spin resonance spectra of free radicals formed in the reaction of metmyoglobins with ethylhydroperoxide.

Free radicals of myoglobins were measured at room temperature with an ESR spectrometer equipped with a flow apparatus. When horse heart MetMb was mixed with an equimolar amount of ethyl hydroperoxide (EtOOH), a well resolved ESR spectrum with 6 lines and a shoulder was observed. It reached a maximum in a few seconds and decayed with a half-life of about 10 s when the final concentrations of MetMb and EtOOH were 200 microM. This decay rate was the same at a MetMb concentration of 50 microM. The maximum molar radical concentration amounted to about half of the total myoglobin. In the case of sperm whale myoglobin, a similar 6-line spectrum reached a maximum in 1 s and decayed with a half-life of a few seconds. In this case, however, a small and poorly resolved doublet spectrum remained, the half-life of which was about 8 min. An effect of O2 on the signal decay was evident for horse heart myoglobin, but not for sperm whale myoglobin.

Animals↗

Squamous cell cancer of the maxillary sinus in Hokkaido, Japan: a case-control study.

A case-control study of squamous cell cancer of the maxillary sinus was performed in Hokkaido with 106 cases and 212 controls matched for sex, age (within five years), and residence (same health centre region). Univariate analyses showed that a history of chronic sinusitis (relative risk, RR = 3.2), nasal polyps (RR = 5.0), an occupational history of being a carpenter, joiner, furniture worker, or other woodworker (RR = 2.9), and current or past smoking habits (RR = 3.0) were statistically significant risk factors for men. No single item was a significant risk factor for women.

Carcinoma, Squamous Cell↗

Staging of bladder carcinoma by magnetic resonance imaging. A preliminary report.

Magnetic resonance imaging (MRI) of bladder carcinoma was performed in 10 patients who subsequently underwent operations for tumor staging. MRI was performed with a 0.1 T resistive magnetic resonance unit. Images were obtained in the transverse, coronal and sagittal directions with different repetition and echo times. Simultaneously, computed tomography (CT) was performed in 9 of the 10 patients. The accuracy of MRI and CT staging was then evaluated by comparison with the staging from pathologic diagnosis. All of the tumors, which were 2.3-6.3 cm in diameter, were readily depicted by both imaging techniques. The overall accuracy of MRI staging for the 10 patients in whom staging had been pathologically confirmed was 90%, while the accuracy of CT staging for the 9 patients was 55%. Although no statistically significant differences in accuracy between CT and MRI staging can be established on the basis of the above results because of the small number of patients included in this study, MRI appears to be a very useful modality for staging bladder carcinoma.

Adult↗

[Clinical evaluation of serum neuron-specific enolase levels in patients with lung cancer].

Serum neuron-specific enolase (NSE) levels were studied in 105 patients with malignant neoplasms (lung cancer 38, others 67), 13 patients with various benign diseases and 7 healthy adults. The mean serum NSE level in adult control subjects was 7.4 +/- 0.8 ng/ml, and cut off level was decided 10 ng/ml. Serum NSE levels were elevated in 14/38 (37%) of patients with lung cancer and in 14/67 (21%) of patients with the other malignant neoplasms. In patients with benign diseases, serum NSE level was elevated only in one patient with pituitary adenoma. In 7 patients with small cell lung cancer, the positive rate was higher (86%) than in those with non-small cell lung cancer (26%), and serum NSE levels were higher than 25 ng/ml except one case. There was no correlation between serum NSE and CEA (carcinoembryonic antigen) levels in patients with small cell lung cancer, also in patients with lung cancer. The measurement of serum NSE level seemed to be useful for diagnosis in patients with small cell lung cancer.

Adult↗