Biomedical subjects

Y Kohno

Publications and source records attributed to Y Kohno.

349 records · Page 20Linked to original sources

PubMedDate not supplied

MR-revealed myelination in the cerebral corticospinal tract as a marker for Pelizaeus-Merzbacher's disease with proteolipid protein gene duplication.

BACKGROUND AND PURPOSE: Pelizaeus-Merzbacher's disease (PMD) is caused by mutations in the proteolipid protein (PLP) gene. Recent studies have shown that an increased PLP dosage, resulting from total duplication of the PLP gene, invariably causes the classic form of PMD. The purpose of this study was to compare the MR findings of PMD attributable to PLP duplication with those of PMD arising from a missense mutation. METHODS: Seven patients with PMD, three with a PLP missense mutation in either exon 2 or 5 (patients 1-3), and four with PLP duplication (patient 4 having larger PLP duplication than patients 5-7) were clinically classified as having either the classic or connatal form of PMD. Cerebral MR images were obtained to analyze the presence of myelination and T1 and T2 shortening in the deep gray matter. Multiple MR studies were performed in six of the seven patients to analyze longitudinal changes. RESULTS: Four patients (patients 1-4) were classified as having connatal PMD, whereas the other three (patients 5-7) were classified as having classic PMD. Myelination in the cerebral corticospinal tract, optic radiation, and corpus callosum was observed in three cases of classic PMD with PLP duplication. In patient 4, myelination extended to the internal capsule, corona radiata, and centrum semiovale over a 3-year period. No myelination was observed in three PMD cases with a PLP point mutation. T2 shortening in the deep gray matter was recognized in all patients with PMD. CONCLUSION: The presence of myelination in the cerebral corticospinal tract with diffuse white matter hypomyelination on MR images could be a marker for PMD with PLP duplication. It is suggested that progression of myelination may be present in connatal PMD with large PLP duplication.

Adolescent↗

PubMedDate not supplied

Copper metabolism after living donor liver transplantation for hepatic failure of Wilson's disease from a gene mutated donor.

There is a genetic problem in living donor liver transplantation, involving Wilson's disease, because the majority of donors have a kinship relationship. Recently, it was reported that the serum ceruloplasmin level is insufficient in some persons with one allele mutation. The recipient was a 13-year-old male child, and the donor was a 22-year-old woman, who was his sister by a different father. The gene analysis for Wilson's disease (ATP7B gene) was preoperatively carried out by the amplification refractory mutation system-PCR. Homozygous and heterozygous deletion of 2871 cytosine (C) were detected in the recipient and donor, respectively, in the ATP7B gene. Serum ceruloplasmin level was sufficient in the donor. The right hepatic lobe graft was transplanted to the recipient. Immediately after the liver transplantation, the copper metabolism improved to increase the serum ceruloplasmin levels up to the normal range, and decrease the urinary copper excretion. However, the serum ceruloplasmin levels gradually decreased below the normal base line, although the urine copper levels continued to be low without any clinical symptoms. We should perform gene analyses and confirm the serum ceruloplasmin levels in donors before living donor liver transplantation for Wilson's disease, to screen for their impairment of copper metabolism. After living donor liver transplantation for Wilson's disease, we should carefully follow-up the transition of serum ceruloplasmin levels in the recipient.

Adenosine Triphosphatases↗

PubMedDate not supplied

Usefulness of magnetic resonance sialography in patients with juvenile Sjögren's syndrome.

OBJECTIVE: Sialography is an important means for evaluating parotid gland damage in patients with Sjögren's syndrome (SS). However, 'conventional' X-ray sialography is invasive and sometimes difficult to perform and repeat, especially for young patients. Recently, magnetic resonance (MR) sialography has been used in adult SS patients. In this study, we investigated the usefulness of MR sialography for evaluating parotid gland damage in juvenile SS. METHODS: Eight young patients suffering from SS were studied. MR sialography and X-ray sialography were performed simultaneously in the same patients. The images obtained by both methods were assessed with Rubin-Holt staging. RESULTS: MR sialography detected ductal dilatation in 5 of 8 patients, while it was detected in 7 of 8 patients by X-ray sialography. The stages were the same in 4 patients by both methods. In 3 patients, the stages on X-ray sialography were higher than those on MR sialography; in 1 patient, the stage on MR sialography was higher. The correlation between the stages determined by the 2 methods was 0.85. There were no side effects in MR sialography, whereas 3 patients complained of pain during X-ray sialography. CONCLUSION: MR sialography can evaluate Stage II approximately III parotid gland damage in juvenile SS. Although MR sialography cannot detect subtle changes in the duct, it has no side effects and can be performed repeatedly in young patients. We propose that MR sialography be chosen as the first tool for diagnosing and during follow-up of the status of the glands in juvenile SS.

Adolescent↗

PubMedDate not supplied

Autoimmune thyroiditis induced in mice depleted of particular T cell subsets. II. Immunohistochemical studies on the thyroiditis lesion.

The intravenous (i.v.) administration of Lyt-1dull T cells into syngeneic (C57BL/6 x C3H/He)F1 T cell-depleted B cell mice resulted in the induction of typical thyroiditis exhibiting massive cellular infiltration. The present study investigated which types of lymphoid cells infiltrate in the thyroiditis lesion and whether immunohistologic change takes place on epithelial cells of thyroid follicles. Both L3T4+ and Lyt-2+ T cells were found in the lesion, although the frequency of infiltration was higher in the former than in the latter. Thyroiditis was also induced by injection of Lyt-1dull L3T4+ but not of Lyt-1dull Lyt2+ T cells, indicating the critical role of a part of L3T4+ T cell subset (Lyt-1dull L3T4+ T cell subpopulation) in inducing thyroiditis. Only rare Lyt-2+ T cells were seen in such a thyroiditis lesion. Infiltrating T cells were predominantly of L3T4+, and these L3T4+ T cells formed cellular infiltrating lesion together with moderate number of B cells and relatively small number of macrophages. Importantly, class II MHC antigens were detected on epithelial cells of thyroid follicles. Such class II MHC expression was observed in coincidence with the area of cellular infiltration in the thyroid. These results demonstrate that: (1) a part of L3T4+ T cells which is required for the induction of thyroiditis by adoptive cell transfer infiltrates into the inflammatory lesion, (2) the induction of the thyroiditis lesion is formed by these L3T4+ T cells as well as B cells and macrophages, but does not necessarily depend on the participation of Lyt-2+ T cell subset, and (3) the aberrant expression of class II MHC antigens on thyroid epithelial cells coincides with cellular infiltration.

Animals↗

PubMedDate not supplied

Study of the lymph flow of the cardia by endoscopic RI-lymphography with SPECT.

Endoscopic RI-lymphography was performed in 29 patients, with single photon emission computed tomography (SPECT) also performed in 19 of them. The lymph flow from the cardia was directly evaluated in lymphograms and compared with the RI uptake of each lymph node and the incidence of lymph node metastasis of previously resected carcinoma of the cardia in patients according to the location of the lymph node. Endoscopic RI-lymphography performed in combination with SPECT was considered to be highly useful for imaging lymph flow of the cardiac region. SPECT and RI-lymphography indicated rich lymph flow from the cardia to the periaortic region, and this finding was consistent with the incidence of lymph node metastasis according to the location of the lymph node in patients who had previously undergone resection of cancer of the cardia. Careful examination for metastasis to lymph nodes around the abdominal aorta was considered to be necessary, especially in patients with carcinoma of the cardia.

Cardia↗

PubMedDate not supplied

[Myocardial ischemia and abnormality of cardiac sympathetic nervous function in apical hypertrophic cardiomyopathy].

Exercise 201Tl myocardial scintigraphy of patients with apical hypertrophic cardiomyopathy (AH) often shows transient perfusion defect in the apex. Catecholamine may be related to the pathogenesis of AH, but this is not certain. The relationship between hypertrophy, myocardial ischemia, and cardiac sympathetic nervous function were investigated by comparing 123I-MIBG myocardial SPECT with exercise 201Tl myocardial SPECT especially at the apex which is the hypertrophic region. Seventeen patients with AH, mean age of 53 +/- 11 years old, underwent 123I-MIBG myocardial SPECT and exercise 201Tl myocardial SPECT on separate days. Decreased tracer uptake regions and the severity and extent of the defect were evaluated visually and compared. Myocardial clearance of 123I-MIBG in apical, midventricular, and basal regions was calculated from the bull's eye display. 123I-MIBG SPECT showed a decreased uptake or defect in the apex of all patients. 201Tl SPECT showed a reversible perfusion defect in the apex of 10 patients, an irreversible perfusion defect in the apex in 3, and normal perfusion in 4. Comparing decreased uptake on the exercise 201Tl myocardial image and 123I-MIBG 4-hour delayed image, the severity of the defect was: MIBG > Tl in 12 patients (71%), MIBG = Tl in 5 (29%), and the extent of the defect was: MIBG > Tl in 11 (65%), MIBG = Tl in 6 (35%). Mean clearance of 123I-MIBG in the apical and midventricular regions was significantly higher than that in the basal region (apical 46.2 +/- 7.1%, midventricular 44.4 +/- 7.8%, basal 38.7 +/- 7.7%).(ABSTRACT TRUNCATED AT 250 WORDS)

3-Iodobenzylguanidine↗

PubMedDate not supplied

[Effect of verapamil on myocardial ischemia in patients with hypertrophic cardiomyopathy: evaluation by exercise thallium-201 SPECT].

The effect of verapamil on myocardial ischemia in patients with hypertrophic cardiomyopathy (HCM) was evaluated by exercise myocardial 201Tl SPECT (EX-Tl). EX-Tl was performed before and after 8.1 +/- 6.1 weeks of oral administration of verapamil (240 mg/day) on 20 patients with HCM who showed transient 201Tl perfusion defects under control conditions. SPECT images were divided into nine segments. The 201Tl perfusion defect was visually scored and evaluated for four grades in each segment and the sum total grade was calculated as the defect score. Transient dilation index was calculated as a reflection of subendocardial ischemia. Improvements in defect score were demonstrated in 18 of 20 patients after administration of verapamil. The mean defect score decreased significantly from 5.1 +/- 2.3 to 2.5 +/- 2.4 (p < 0.001). Although 18 of 20 patients showed abnormal transient dilation index under control conditions, 16 showed improvement and 12 were normalized after verapamil therapy. Mean transient dilation index decreased from 1.24 +/- 0.19 to 1.08 +/- 0.10 (p < 0.01). Verapamil improves myocardial ischemia in patients with HCM.

Cardiomyopathy, Hypertrophic↗