Biomedical subjects

K Matsubara

Publications and source records attributed to K Matsubara.

602 records · Page 34Linked to original sources

PubMedDate not supplied

A study of derivative spectrophotometry for the determination of carboxyhemoglobin in blood.

An application of derivative spectrophotometry to the determination of carboxyhemoglobin (HbCO) in blood was examined. The 1st, 2nd, 3rd, and 4th derivative spectra were recorded in the Soret region for HbCO, reduced hemoglobin (Hb), and their mixed solution. The 4th derivative spectrum had the highest sensitivity to the change of HbCO-Hb ratio in the solution. A maximum point of the 4th derivative curve was employed for the HbCO determination. Blood samples with varied HbCO concentrations were analyzed using this technique and the results were compared with those obtained by conventional spectrophotometric and gas chromatographic procedures. The derivative method was in satisfactory agreement with both procedures.

Carboxyhemoglobin↗

PubMedDate not supplied

Determination of carboxyhemoglobin in heated blood--sources of error and utility of derivative spectrophotometry.

The cause for discrepancies in results from different methods of the carboxyhemoglobin (HbCO) analysis on the blood from bodies of burn victims was investigated. Blood samples with 0, 50, and 100% carbon monoxide (CO) saturation were heated at various temperatures for some time and then analyzed. Carboxyhemoglobin content was determined by the fourth-derivative spectrophotometric method and compared with results from the usual two-wavelength method. For total hemoglobin measurement, the fourth-derivative technique and cyanmethemoglobin method were used. Turbidity in blood samples, which occurred when samples were heated above 50 degrees C, affected the analysis. At about 70 degrees C, coagulation and hemoglobin degeneration occurred accelerating the errors of determined values. The fourth-derivative technique, however, proved to be independent of the turbidity and would be useful for the analysis on the blood without hemoglobin degeneration.

Carboxyhemoglobin↗

PubMedDate not supplied

Chromosomal mapping of 18S-28S rRNA genes and 10 cDNA clones of human chromosome 1 in the musk shrew (Suncus murinus).

The direct R-banding fluorescence in situ hybridization (FISH) method was used to map 18S-28S ribosomal RNA genes and 10 human cDNA clones on the chromosomes of the musk shrew (Suncus murinus). The chromosomal locations of 18S-28S ribosomal RNA genes were examined in the five laboratory lines and wild animals captured in the Philippines and Vietnam, and the genes were found on chromosomes 5, 6, 9, and 13 with geographic variation. The comparative mapping of 10 cDNA clones of human chromosome 1 demonstrated that human chromosome 1 consisted of at least three segments homologous to Suncus chromosomes (chromosomes 7, 10, and 14). This approach with the direct R-banding FISH method is useful for constructing comparative maps between human and insectivore species and for explicating the process of chromosomal rearrangements during the evolution of mammals.

Animals↗

PubMedDate not supplied

MR detectability of posterior pituitary high signal and direction of frequency encoding gradient.

The reported rate of detection of the posterior pituitary high signal (PPHS) in T1-weighted MR images has varied. The purpose of this study was to clarify the influence of the direction of the chemical shift on the detectability of the PPHS. Fifty-three subjects with a normal pituitary gland (n = 41) or an empty sella (n = 12) were studied with sagittal T1-weighted spin-echo imaging using two or three different frequency encoding gradient (FEG) directions: caudocephalad (FEG: CH), cephalocaudad (FEG: HC), and anteroposterior (FEG: AP). The PPHS was detected and clearly separated from the high signal of the fatty marrow of the dorsum sellae in 54% of the normal pituitary gland and 25% of the empty sella cases with FEG: CH, and in none of the cases (n = 5) with FEG: HC. The chemical shift of the fatty marrow in the dorsum sellae tended to overshadow the PPHS when FEG: CH and HC were used. In contrast, when FEG: AP was used, the PPHS was clearly separated from the dorsum sella marrow fat in all cases. Frequency encoding gradient: AP represents the optimal setting for evaluating the posterior pituitary gland.

Adolescent↗

PubMedDate not supplied

Ocular involvement and visual sequelae in hemophagocytic lymphohistiocytosis in association with congenital dyfsfibrinogenemia.

We report a 7-year-old girl with hemophagocytic lymphohistiocytosis and an uncommon complication of vascular retinopathy and visual sequelae. She was also verified to be complicated with dysfibrinogenemia. The patient was treated with etoposide, dexamethasone, and cyclosporin A. During the fifth hospital week, a generalized tonic-clonic convulsion developed followed by deep coma. When she regained full consciousness, she complained of a visual disturbance. The ophthalmologic examination showed bilateral extensive retinal edema with numerous cotton-wool spots, indicative of vaso-occlusive retinopathy. This is inconsistent with the main finding of previous cases with ocular involvement, namely papilledema. Severely reduced visual acuity and visual field defects remained in both eyes even after systemic therapy. An awareness of this rare but serious complication is important because it may be preventable by early institution of chemotherapy. The pathogenesis of the retinopathy is also discussed.

Afibrinogenemia↗

PubMedDate not supplied

Genomic DNA analyses of spontaneous hepatocellular carcinomas in LEC rat liver using a new technique.

An inbred rat strain, LEC (long evans cinnamon) has been used as a model of human Wilson's disease. This animal suffers from a severe type of hepatitis, the clinical manifestations of which are similar to human fulminant hepatitis for 4-5 months which is caused by accumulation of copper in the liver. The surviving rats develop chronic hepatitis, followed by the development of spontaneous hepatoma. In contrast to studies with hepatocellular carcinomas (HCCs), the studies have great advantages in that the animals have identical genetic background, can be raised under a fixed condition, and the development of HCC is reproducible. We took two HCC samples and analysed their genomic DNA using RLGS (restriction landmark genomic scanning), which involves two-dimensional electrophoresis of genomic DNA allowing the survey of some 1,000 NotI sites throughout the genome. Using this technique, we discovered landmark spots that were either decreased or increased in intensity in HCC and compared them with the RLGS profile obtained from the DNA of control normal LEC rat liver. Approximately 1,300 spots were compared, and the intensity of two spots was found to be decreased about half and one was increased 1.3-1.7 folds. Although the mechanism of these changes and the properties of the changed DNA are yet to be studied, recurrent genomic changes in the LEC rat HCC could prove to be a good model system for elucidating the essential genetic events in association with hepatocarcinogenesis.

Animals↗

PubMedDate not supplied

Enzymatic oxidation of 7-hydroxylated delta 8-tetrahydrocannabinol to 7-oxo-delta 8-tetrahydrocannabinol by hepatic microsomes of the guinea pig.

Hepatic microsomes of the guinea pig converted delta 8-tetrahydrocannabinol (delta 8-THC) to various oxidized metabolites, including 7 alpha-hydroxy-delta 8-THC (7 alpha-OH-delta 8-THC), 7 beta-OH-delta 8-THC, and 7-oxo-delta 8-THC. The enzyme which mediates biotransformation of 7-OH-delta 8-THCs to 7-oxo-delta 8-THC was characterized in the present study. The oxidative activity was mainly located in microsomes. The microsomal reaction required NADPH and oxygen and showed an optimal pH around 7.5. The reaction was inhibited by beta-diethylaminoethyl diphenylpropylacetate (SKF 525-A), an inhibitor of cytochrome P-450, but not by pyrazole, a specific inhibitor of alcohol dehydrogenase. However, 7-oxo-delta 8-THC formation was not affected by carbon monoxide or by pretreatment of animals with cobaltous chloride (40 mg/kg, ip, once a day for 3 days). Atmospheric oxygen was incorporated into 7-oxo-delta 8-THC formed from 7 alpha-OH-delta 8-THC, but not into that from 7 beta-OH-delta 8-THC. Further, 7-oxo-delta 8-THC formed from 7 alpha-18OH-delta 8-THC released about half of 18O at the 7-position, whereas the 7-oxo metabolite from 7 beta-18OH-delta 8-THC lost little of the isotope at the 7 beta-position during the oxidative reaction. From these results, it is likely that hepatic microsomal monooxygenase (probably cytochrome P-450) plays a main role in the oxidation. In addition, mechanisms for 7-oxo-delta 8-THC formation from 7 alpha-OH-delta 8-THC or 7 beta-OH-delta 8-THC are different.

Animals↗

PubMedDate not supplied

Salsolinol in the urine of nonalcoholic individuals after long-term moderate drinking.

Urine samples were collected before breakfast from 94 normal volunteers (41 males and 53 females) aged 25-70 years. Salsolinol (SA) was analyzed by gas chromatography-mass spectrometry (GC/MS), and dopamine, norepinephrine and epinephrine were determined using high performance liquid chromatography (HPLC). SA levels were significantly higher in the urine of male moderate drinkers (MDs) than in male seldom or non drinkers (SNDs). In females, however, a significant difference of urinary SA levels was not observed between MDs and SNDs. There was a sex difference of urinary SA levels among SND subjects, i.e., females showed a higher SA than males. Urinary catecholamines were not significantly altered by long-term moderate alcohol drinking in either sex. There was no correlation between urinary levels of dopamine and SA. These results indicate that urinary SA can be increased by long-term drinking even in normal, not alcoholic subjects.

Acetaldehyde↗