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Biomedical subjects

A Kodama

Publications and source records attributed to A Kodama.

106 records · Page 6Linked to original sources
PubMed1976

Simultaneous determination of eight vitamin D2 isomers by high-speed liquid chromatography.

The simultaneous determination of vitamin D2 and its isomers by high-speed liquid chromatography (HSLC) is described. Preferred operating conditions for the resolution and quantitation of vitamin D2 5,6-trans-vitamin D2, ergosterol, lumisterol2, isovitamin D2, isotachysterol2, tachysterol2, and previtamin D2 are as follows: column, "Zorbax" SIL (25 cm x 2.1 mm i.d.); pressure, 100-120 kg/cm2; temperature, ambient; detector, UV 254 nm; mobile phase, 0.15% methanol + 2% ether in pentane (for the simultaneous determination), 10% ether in hexane (for quantitation of the practical sets of isomers), or 55% CHCl3 (distilled) in pentane (for separation of isovitamin D2 and 5,6-trans-vitamin D2); sample size, 1 mul (greater than 1-5 ng); internal standard, p-cresol or alpha-naphthol. High-speed, good resolution, precise and accurate trace analysis, greater analysis flexibility, no necessity for preparing derivatives, and gentle operating conditions are main potential advantages of our method which has proved to be very efficient and surpasses all analytical procedures hitherto proposed.

Chemical Phenomena↗
PubMed1975

Nonbacterial thrombotic endocarditis in a Japanese autopsy sample. A review of eighty cases.

A study of nonbacterial thrombotic endocarditis has been carried out in a series of 3,404 autopsies performed upon atomic bomb survivors in Hiroshima in the period 1953-1970. The prevalence of the lesion was 2.4 per cent, with a greater frequency among the elderly and among females, and with a significant relationship to malignant neoplasms. In contrast to other reported series, there was a greater prevalence among cancers of the colon, rectum, and female genitourinary tract. No relationship was noted between the presence of NBTE and exposure to ionizing radiation. Histologic findings in the heart-valve leaflets in close proximity to the verrucae, like experimental studies reported by others, suggest that in association with severe systemic disease there appears a process consisting of degenerative changes in valve collagen and ground substance, with subsequent denudation of endothelium, localized almost entirely to the apposing leaflet surfaces of the left-heart valves. The verrucae of nonbacterial thrombotic endocarditis are then formed upon this abnormal leaflet surface. While the relationship between systemic disease and the pathologic changes observed in cardiac valve tissue is unclear, and although it is not known whether a "hypercoagulable state" may accentuate the tendency for thrombi to form upon these abnormal valves, there is no doubt that this lesion represents a clinically important complication of severe systemic disease. It also seems likely that in some cases NBTE may complicate an illness which may otherwise be curable. Increasing awareness of this pathologic entity among clinicians, coupled with appropriate laboratory techniques, most likely echocardiography, will permit more frequent diagnosis in living patients.

Adenocarcinoma↗
PubMedDate not supplied

Sudden deafness in relapsing polychondritis. A scanning electron microscopy study.

The left ear of a 57-year-old female who suffered sudden deafness during the course of relapsing polychondritis was examined under a scanning electron microscope. Marked degeneration of the organ of Corti in all turns and dislocated and encapsulated tectorial membrane were found in the cochlea. Marked decrease in number of the sensory cells in the utricular and saccular maculae and total loss of sensory hair bundles in the ampullary cristae of the semicircular canals were seen in the vestibule. These findings strongly suggest that the cause of sudden deafness in this case might be viral. The usefulness of scanning electron microscopy in human temporal bone pathology is stressed.

Acoustic Maculae↗
PubMedDate not supplied

Temporal bone findings in a case of sudden deafness and relapsing polychondritis.

Light microscopic examination was made of the right temporal bone from a 57-year-old female who developed sudden total hearing loss in both ears 1 year before death. The patient had suffered from relapsing polychondritis for 1 1/2 years prior to death. Pathological changes were compatible with known viral endolymphatic labyrinthritis. Slight ossification and fibrous tissue proliferation in the perilymphatic space seem to have been caused by a spread of infection from the middle ear. Susceptibility to viral infection in the labyrinth in patients with a long-devastating illness is discussed.

Acoustic Maculae↗
PubMedDate not supplied

Expression of pulmonary mRNA encoding ICAM-1, VCAM-1, and P-selectin following thoracic irradiation in mice.

PURPOSE: Recent studies have revealed that ionizing radiation induces the expression of intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1), and P-selectin in vitro. The purpose of this study was to investigate the expression of these adhesion molecules in mouse lung following whole thoracic irradiation. MATERIALS AND METHODS: C57BL/6J mice were irradiated with a single dose of 12 Gy to the thoraces and sacrificed at 4, 12, 24, and 48 hours and 1, 2, 4, and 8 weeks after irradiation. Expression of total lung mRNA for ICAM-1, VCAM-1, and P-selectin was quantified by the Northern blot method and normalized to beta-actin. RESULTS: There were increases in mRNA for ICAM-1 of 42% at 4 hours (p < 0.05), 76% at 24 hours (p < 0.01), and 51% at 48 hours (p < 0.05) compared with the controls. These returned to the control level at 1 week. The expression of VCAM-1 mRNA was also increased by 49% (p < 0.01) at 12 hours and was still increased by 25% at 1 week. P-selectin mRNA was transiently increased by 59% at 12 hours. CONCLUSIONS: These early inductions of mRNA for ICAM-1, VCAM-1, and P-selectin in mouse lung following thoracic irradiation were transient but significant, and are one of the most immediate changes reported in vivo.

Animals↗
PubMedDate not supplied

Dimensional anatomy of the vestibular aqueduct and the endolymphatic sac (rugose portion) in human temporal bones. Statistical analysis of 79 bones.

The purpose of this study was to investigate the anatomy of the vestibular aqueduct (VA) and rugose portion (RP) of the endolymphatic sac. Serial horizontal sections of 79 normal temporal bones of individuals aged 20 to 102 years were used. Medial view graphic reconstruction of the VA was performed for each specimen to determine the area, length, angle and position of the VA. The relationship between the width of the VA and the area of the VA, and the relationship between the degree of development of the VA and the degree of development of the temporal bone (periaqueductal pneumatization and the otic capsule in the periaqueductal region) were also investigated. Measurements of the RP were also made and further histological study of the RP was performed on 30 selected specimens. We found that 1) the VA in adult temporal bone varies in size and can be classified as hypoplastic, normoplastic, or hyperplastic; 2) many of the VAs in each group have similar sizes, although they vary in length, angle, or position; 3) all or most of the RP was located within the VA in all but one specimen, which had a hypoplastic VA (in this specimen more than half of the entire RP extended into the posterior cranial fossa); 4) the histology of the RP was characteristic in each type of VA; and 5) the degree of development of the VA seems to correlate with the degree of development of the otic capsule in the periaqueductal region.

Adult↗
PubMedDate not supplied

Postnatal development of the vestibular aqueduct and endolymphatic sac.

The purpose of this study was to gain basic information about the postnatal development of the vestibular aqueduct (VA) and the endolymphatic sac (ES). For this study, serial horizontal sections of 31 normal temporal bones of individuals whose ages ranged from 0 to 13 years were used. Medial view graphic reconstruction of the VA and rugose portion (RP) of the ES was performed in every case for analysis of the VA and RP. The findings of this study revealed the following new information about the postnatal development of the VA and ES. 1) The VA and RP undergo significant growth postnatally up to age 3 years. 2) In the newborn, individual variations in the VA and RP already exist and at age 3 years significantly wide individual variations which can be classified into three groups (hypoplastic, normoplastic, hyperplastic) may be recognized. 3) Hypoplastic VAs are of two types: one is fairly elongated and tubelike while the other is short and funnel-shaped. The tubelike VA seems to be the prenatal form. 4) The changes that occur with development postnatally in the area of the VA are more closely related to the changes that occur in the length of the external aperture of the VA than they are to the changes that occur in the length of the VA. 5) Development of the area of the VA is closely correlated with development of the area of the RP.

Adolescent↗