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T Kajima

Publications and source records attributed to T Kajima.

At least 19 recordsLinked to original sources
PubMed1998

A decrease in cerebral cortex intensity on T2-weighted with ageing images of normal subjects.

To determine the change in intensity in the cerebral cortex on T2-weighted MRI with ageing, we reviewed the T2-weighted images of 83 normal subjects and measured the signal intensity in the cerebral cortex in 30 subjects randomly selected from them. Low-intensity areas were more common in the cerebral cortex of the aged. The intensity of different cortical regions varied, and the intensity in the temporal and parietal to be decreased with ageing. Presumably, this change of the intensity reflects senile changes, although low intensity is not evident in the temporal cortex because of its high basal intensity level.

Aging↗
PubMed1997

An improved assay method for fibroblast gelatinolytic enzyme.

A useful gelatinolytic enzyme assay for fibroblasts, utilizing a novel sample preparation method for collagenase with dithiothreitol (DTT) treatment to inactivate endogenous collagenase inhibitors, was developed using soluble fluorescein isothiocyanate (FITC)-labeled gelatin. The substrate, gelatin was prepared by heating commercially available FITC-labeled type I collagen. The denatured collagen was cleaved with purified trypsin and partially purified fibroblast gelatinase, and the digested FITC-fragments were measured fluorometrically. The intensity of the fluorescence was in proportion to the reaction time and enzyme concentration. Both enzyme activities were measurable within the nanogram range of enzyme preparations. The enzyme activity was detected after 4-aminophenylmercuric acetate (APMA) treatment which was completely inhibited by metalloproteinase inhibitors, but not by serine- and cysteine-proteinases' inhibitors. Conditioned media of human periodontal ligament fibroblasts (PLF) and gingival fibroblasts (GF) were separately treated with DTT prior to the enzyme assay, and then the assay was performed in the presence of APMA. The enzyme activities of PLF and GF were 106- and 55-fold higher than those of the conventional gelatinase assay which was carried out without DTT treatment. This assay method allowed the measurement of gelatinolytic enzyme activity when tissue inhibitors of metalloproteinases were present in the fibroblast culture medium.

Biological Assay↗
PubMed1995

Low intensity areas observed on T2-weighted magnetic resonance imaging of the cerebral cortex in various neurological diseases.

The cerebral cortex of patients with Alzheimer's disease (AD) or amyotrophic lateral sclerosis (ALS) may show low signal intensity on T2-weighted magnetic resonance images (MRI). Since these low intensity areas (LIA) are also often observed in aged patients with other diseases, we suspected that they might be a non-specific finding. We conducted a retrospective study of LIA in 139 patients with various diseases of the central and peripheral nervous systems, and evaluated their relationship to age and other MRI findings. Brain atrophy, ventricular dilatation, white matter lesions, and LIA were visually evaluated on axial images of the spin echo sequences obtained with a 1.5 tesla (T) system. We found that LIA appeared after age 50 and became more common with advancing age. Their presence correlated with brain atrophy and white matter lesions. They were most frequent in the motor cortex, followed by the occipital and sensory cortices. Their incidence in the motor cortex was significantly higher in patients with central nervous system diseases than in those with peripheral neuropathy. We conclude that LIA are common in old patients with various neurological diseases and suggest that the deposition of iron in the cerebral cortices causes their development.

Adolescent↗
PubMed1995

[Experimental study on early detection of alloxan-induced pulmonary injury by magnetic resonance imaging].

We studied the early detection of alloxan-induced pulmonary injury by magnetic resonance imaging in vivo. Permeability edema was induced in ten rats by intravenous injection of alloxan at 100 mg/kg. T1-and T2-weighted images were acquired in five rats every 30 min for 120 min after alloxan injection. Five rats served as controls. The rats were sacrificed immediately after imaging and examined microscopically. CT images were also acquired in five rats every 30 min for 120 min after alloxan injection. Five rats served as controls. The rats were sacrificed immediately after imaging, and the wet-to-dry ratio of the lung was measured. In T1-weighted images, relative signal intensity from the lung with permeability edema rose from 30 min to 120 min, and was greater than that from normal lung every time. In T2-weighted images, there was no statistically significant difference in relative signal intensity of the lung between permeability edema and the control during 120 min. In CT images, there was also no statistically significant difference in lung density between permeability edema and the control during 120 min. There was no statistically significant difference in the wet-to-dry lung ratio between edematous lung and normal lung. In histological study, mild congestion and interstitial edema were observed in edematous lung. These results suggest the potential capability of MR imaging in detecting the early phase of permeability pulmonary edema.

Alloxan↗
PubMed1995

[Intratumoral LPD deposition within hepatocellular carcinoma without arterial tumor staining].

The dissociation of intratumoral LPD deposition and arterial tumor staining was investigated in 20 cases of hepatocellular carcinoma (HCC) without arterial tumor staining. The intratumoral deposition of LPD injected from the hepatic artery was observed in nine cases of HCC and coincided with the decrease in tumor vascular bed evaluated by photomicroscopic study and arterial portography. LPD deposition was not observed within the 11 other tumors, which were diagnosed as well differentiated HCC. Infusion angiographic CT revealed that the arterial and portal vascular beds were separated from each other. Therefore, arterial tumor staining was insufficient for accurate evaluation of the tumor vascular bed. The vascular bed in cancerous and noncancerous tissue was accurately evaluated by the addition of the contrast enhancements from the hepatic artery and the portal vein.

Carcinoma, Hepatocellular↗
PubMed1994

Diffusion anisotropy of cerebral ischaemia.

Focal cerebral ischemia was produced by occlusion of the middle cerebral artery with a silicone cylinder in Wistar rats. Diffusion-weighted echo-planar images (DW-EPIs) using the motion-probing gradient (MPG) method were acquired at 1-3 hours and 24-48 hours after occlusion. Apparent diffusion coefficients (ADCs) were calculated from these images in ischemic lesions and in normal unoccluded regions. Results were as follows. 1. Ischemic lesions could be detected on the DW-EPIs at 1 hour after occlusion. 2. The ADC of water in the brain tissue was smaller than that of free water as a result of restricted diffusion. 3. Anisotropic diffusion that probably can be attributed to the myelin sheath was observed in the normal deep white matter. 4. In the ischemic lesions, the ADC decreased rapidly within 1-3 hours after occlusion and then slightly further declined after 24-48 hours. In the ischemic deep white matter, diffusion anisotropy disappeared at 24-48 hours after occlusion. Diffusion-weighted imaging may have applications in the examination of pathophysiological mechanisms in cerebral ischemia by means of evaluation of ADC and diffusion anisotropy.

Animals↗
PubMed1991

Column-switching high-performance liquid chromatography for on-line simultaneous determination and resolution of enantiomers of verapamil and its metabolites.

An on-line simultaneous assay for the enantiomers of verapamil (VA) and its three metabolites in plasma was developed with column-switching HPLC. This system consists of an ovomucoid protein chiral stationary phase coupled to an achiral reversed-phase column via a dilution tube and a trapping column. The reversed-phase column was used to separate and quantitate VA, its metabolites, and internal standard, without interference from plasma components. Then each of the eluates containing VA and its metabolites was selectively switched into a sampling loop, and the samples were transferred successively to the trapping column after dilution with a new mobile phase. After concentration on the trapping column, each sample was passed to the ovomucoid column, where the enantiomers were resolved and quantitated. The mobile phases for both HPLC columns were independently optimized and the diffusion of the sample during column switching was minimized. This method was shown to be efficient and reliable.

Chromatography, High Pressure Liquid↗
PubMed1990

Magnetic resonance imaging of Chiari malformations.

The authors describe the features of magnetic resonance (MR) images of Chiari type I and II malformations and present four illustrative cases. Downward displacement of the posterior fossa was more pronounced with type II than type I. A variety of intracranial anomalies were associated with the Chiari type II malformation, whereas type I was mainly associated with syringomyelia and craniovertebral changes. MR imaging is useful in the diagnosis of intracranial anomalies and those situated at the craniovertebral junction, including Chiari malformations.

Adult↗
PubMed1990

[A case of arachnoid cyst in the posterior fossa with lower cranial nerve palsy].

We experienced a rare case of arachnoid cyst in the right cerebellomedullary cistern. A 59-year-old female was admitted to our clinic because of lower cranial nerve palsy (deviation of uvula to the left side, swallowing disturbance, curtain sign, hoarseness, atrophy of the right sternocleidomastoid muscle, and deviation of the tongue to the right side). MRI demonstrated a mass lesion compressed towards the medulla oblongata in the right cerebellomedullary cistern. MRI was very helpful as a diagnostic tool, since there is no bone object in the posterior fossa. Although by CT cisternography, the arachnoid cyst was thought to have a communication with the surrounding subarachnoid spaces, the cyst wall was removed because of its compressive symptoms on the lower cranial nerves. After the operation, the cyst shrank, and the clinical symptoms were reduced.

Arachnoid↗
PubMed1989

[Lymphocytic adenohypophysitis: MRI findings of a suspected case].

We report a case of a 26-year-old woman who had developed decrease of visual acuity, and restriction of the temporal visual field of the left eye in the 30th week of gestation. A skull roentgenogram showed no abnormality, but a pituitary mass was visualized by plain computed tomographic scan. Magnetic resonance imaging (MRI) demonstrated a symmetric sellar mass which had homogeneous signal intensity in all pulse sequences. T1 relaxation time of the mass was elongated as compared with that of a normal pituitary gland. The height of the mass was 11mm, and optic chiasm appeared compressed by the mass. Her visual disturbance improved before delivery, and the size of the pituitary mass regressed spontaneously. Although no histological examination was carried out, the most likely explanation for this phenomenon is lymphocytic adenohypophysitis. Early surgical intervention is not required for lymphocytic adenohypophysitis, because this disorder may be self-limiting, and may resolve itself. Most of these cases have been reported in women, often coincident with pregnancy. So we consider that MRI is the most useful and safest method for diagnosis and follow-up of this disease.

Adult↗
PubMed1988

[Magnetic resonance imaging of hypothalamic hamartoma].

Magnetic resonance (MR) findings of two patients with a hypothalamic hamartoma are discussed. The two girls showed clinical symptoms and endocrinological signs of precocious puberty. MR imaging was of diagnostic value superior to that of CT in the demonstration of the characteristic location of this tumor and relationships to the neighboring structures because of its multi-dimensional utility. Although it has been reported that CT showed this lesion as isodense to the grey matter with and without injection of contrast medium, MR imaging depicted the lesion as a high signal intensity area on T 2-weighted images in both patients. MR imaging is a useful method for the evaluation of the hypothalamic hamartoma.

Child↗
PubMed1985

[Clinical study on serum immunosuppressive factors in gastric cancer patients--with special reference to preoperative ferritin levels and influence of surgical stress].

Serum ferritin values were measured preoperatively in 83 patients with gastric cancer and were found to be significantly higher than in normal subjects and mammary cancer patients. They were also significantly higher in healthy men than in women and in gastric cancer patients at stages I and IV than in those at stage III. There was no significant correlation between the serum ferritin value and various immunologic parameters. OK-432 serially administered pre- and postoperatively (A) and only postoperatively (B). The ferritin value increased markedly at one week postoperatively, reaching a peak at two weeks; at four weeks, it was reduced toward the value at one week. However, these changes in ferritin value showed no significant difference between groups A and B.

Blood Transfusion↗
PubMed1984

[4 Cases of malignant mesenteric tumor].

Four patients with malignant mesenteric tumors are presented. The first was an 81-year-old male who had non-Hodgkin's lymphoma, the 2nd a 66-year-old male with leiomyosarcoma, the 3rd a 35-year-old male with well differentiated fibrosarcoma. All 3 of these patients underwent radical excision. The 4th patient was a 63-year-old male who underwent exploratory laparotomy only. Postmortem study showed leiomyosarcoma. Based on those and published experiences, we suggest that as soon as a diagnosis of mesenteric tumor has been established with CT scan, GI series etc., surgical removal and Chemotherapy should be performed.

Adult↗
PubMed1984

[Leiomyosarcoma of the rectum--a case report].

Tumors of smooth muscle origin are relatively uncommon in the rectum. Patients with leiomyosarcoma are very infrequently encountered. The patient was a 59-year-old Japanese male, who presented complaining of difficulty of defecation and melena. Rectal examination revealed an elastic hard and smooth-surfaced tumor of walnut size at 4 cm on the left antero-lateral wall. Needle biopsy was performed and the tumor was resected trans- sacrally. Histopathologically the tumor, was diagnosed to be leiomyosarcoma. Although the patient received no postoperative chemotherapy or irradiation, he is living without any symptoms or signs of recurrence 5 years and 6 months after the surgery.

Biopsy, Needle↗