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Biomedical subjects

K Tashiro

Publications and source records attributed to K Tashiro.

At least 451 records · Page 25Linked to original sources
PubMed1989

[Immunohistochemical localization and significance of ornithine aminotransferase in gut and liver in rats].

This study was performed to elucidate immunohistochemical localization of OAT in the gut mucosa and liver of rats using the ABC method. In the normal rat gut mucosa, strong immunoreactivity of OAT as fine granules was present in the surface epithelial cells and apical portion of intestinal glands. In the liver, this reaction was observed in the range of zone 2 to 3 of the pericentral vein and periportal vein. The changes in the intestinal glands of rats with a hyperprotein intake were observed to peak at 2 weeks, but in the liver a strongly positive diffuse reaction throughout whole lobules was detected at 4 weeks. This immunoreactive morphological localization of OAT suggests the location of absorption of amino acids in the small intestine and the distribution of the urea cycle enzyme OAT in the liver. The relationship between absorption of amino acids in the small intestine and the distribution of OAT in the liver was assumed to facilitate feedback repression. The changes in OAT in the mitochondria showed many diverse patterns by immunochemical electron microscopy, and these reactions are presumed to facilitate various types of metabolism in a single cells.

Animals↗
PubMed1988

Macrophages phagocytose thymic lymphocytes with productively rearranged T cell receptor alpha and beta genes.

The thymus gland is important for the formation of competent T lymphocytes. However, there is long-standing evidence that greater than 95% of newly formed thymocytes do not emigrate to peripheral lymphoid tissues but instead die locally. We have identified a rapid and selective pathway for thymocyte turnover in vitro. The mechanism entails binding, uptake, and digestion by macrophages. The susceptible cells are a subpopulation of double-positive thymocytes. These thymocytes can be enriched by virtue of their high buoyant density in Percoll and prove to have low levels of surface CD3 and little or no surface TCR. However TCR-alpha and -beta genes have undergone rearrangement, and full length alpha and beta transcripts are abundant. Therefore many double-positive cells rearrange and express TCR genes but do not have normal levels of TCR on the cell surface. We propose that thymocytes that undergo high turnover in situ are unable to form receptors that can be selected by MHC molecules in the thymus, and that these cells are recognized and cleared by the macrophage.

Gene Rearrangement, T-Lymphocyte↗
PubMed1988

Primary structure of rat liver alkaline phosphatase deduced from its cDNA.

Rat liver alkaline phosphatase (ALP) was markedly induced by treatment of rats by bile-duct ligation and colchicine injection. Taking this advantage for enrichment of ALP mRNA, we constructed a lambda gt11 liver cDNA library using polyadenylated RNA prepared from the treated rat liver, and isolated an ALP cDNA clone. The 2165 bp cDNA contained an open reading frame that encodes a 524-amino-acid-residue polypeptide with a predicted molecular mass of 57737 Da. The precursor protein contained a presumed signal peptide of 17 amino acid residues followed by 28 amino acid residues identical with the N-terminal sequence determined from the purified rat liver ALP. It was also confirmed that amino acid sequences of two CNBr-cleavage peptides obtained from liver ALP were contained within the cDNA-encoded protein. Five possible N-linked glycosylation sites were found in the molecule and a highly hydrophobic amino acid sequence at the C-terminus. The deduced polypeptide of rat liver ALP showed 88% homology to that of the human liver-type enzyme in osteosarcoma cells. RNA blot hybridization analysis identified a single species of ALP mRNA with 2.7 kb in both the control and the treated rat livers. An approx. 20-fold increase of the mRNA was detected in the treated liver at 12 h after the onset of stimulation, compared with that in the control liver.

Alkaline Phosphatase↗
PubMed1988

HTLV-I-associated myelopathy: oligoclonal immunoglobulin G bands contain anti-HTLV-I p24 antibody.

Human T-cell lymphotropic virus type I (HTLV-I)-associated myelopathy (HAM) and tropical spastic paraparesis belong to a new group of neurological diseases associated with retroviral infection. An HTLV-I-like virus has recently been implicated in multiple sclerosis as well. We studied paired cerebrospinal fluid and serum specimens from HAM and multiple sclerosis patients by isoelectric focusing and an isoelectric focusing HTLV-I p24 overlay technique to clarify the role of HTLV-I in these diseases. We detected oligoclonal bands by isoelectric focusing with silver-staining in cerebrospinal fluid, but not serum, from all 5 HAM and all 9 multiple sclerosis patients. An isoelectric focusing HTLV-I p24 overlay technique demonstrated anti-p24 antibody in HAM cerebrospinal fluid at a different pI distribution than that seen in paired serum, indicating local synthesis of anti-p24 antibody within the central nervous system. Oligoclonal bands in HAM cerebrospinal fluid corresponded in pI distribution to anti-p24 antibody activity, suggesting the presence of an ongoing HTLV-I infection in the central nervous system. Multiple sclerosis patients had no evidence of anti-HTLV-I activity by p24 radioimmunoprecipitation assay, Western immunoblots, or isoelectric focusing HTLV-I p24 overlay analysis. Our data support a role for HTLV-I as an etiological agent in HAM, but not in multiple sclerosis.

Blotting, Western↗
PubMed1988

A possible maternal-effect mutant of Xenopus laevis: II. Studies of RNA synthesis in dissociated embryonic cells.

Embryos from a female of Xenopus laevis (designated as no. 65) arrest development at gastrulation and are assumed to be ova-deficient mutant. We dissociated these embryos and studied RNA synthesis at different stages. The cells from the ova-deficient embryos reaggregated quite actively as wild-type embryo cells until the late gastrula stage. RNA synthesis was normal at the early blastula stage but greatly inhibited by the late blastula (stage 9.5) stage, when the synthesis of DNA and protein was still not inhibited appreciably. Thus, inhibition in RNA synthesis appears to be the first manifestation of the maternal defect that occurs before the gastrulation arrest.

Animals↗
PubMed1988

Differentiation of an interleukin 3-dependent precursor B-cell clone into immunoglobulin-producing cells in vitro.

Precursors to B-cell lines with immunoglobulin genes in the germ-line context have been shown to be capable of generating mature B cells in vivo. We report here that an interleukin 3-dependent precursor B-cell line, LyD9, differentiated in vitro into mature B cells, producing IgM and IgG by coculture with bone marrow accessory (or stroma) cells or with dendritic cells and T cells. Up to 50% of IgM-positive cells, but no Thy-1-positive cells, appeared after the 7- to 10-day coculture. Induced LyD9 cells underwent heterogenous immunoglobulin gene rearrangement and synthesized mRNAs encoding immunoglobulin mu, gamma, and kappa chains. However, these cells did not show any rearrangement of genes encoding the alpha and beta chains of the T-cell receptor. The induction of differentiation by coculture with bone marrow stroma cells was blocked by anti-lymphocyte function-associated antigen 1 or anti-interleukin 4 antibody. These systems are useful for molecular biological studies on regulation of differentiation of bone marrow-derived cells into the B-cell lineage.

Animals↗
PubMed1988

[Radiological diagnosis of chronic spinal cord compressive lesion at thoraco-lumbar junction].

Radiological findings in five cases with chronic spinal cord compressive lesion at thoraco-lumbar junction were reported. Three cases had spondylosis and two cases had ossification of yellow ligament (OYL). The levels of the lesions were T12/L1 in three cases and T11/12 in two cases. Two out of three spondylotic patients had also OYL at the same level. The five cases consisted of three men and two women. The ages ranged from 42 to 60 years old with a mean age of 53 years old. Neurologically, every patient showed flaccid paresis and sensory disturbance of the legs. Two cases had sensory disturbance of stocking type. The intervals from the onset of the symptoms to the final diagnosis were 6 months, 7 years, 8 years, 11 years and 12 years. Myelography showed anterior spinal cord compression by bony spur in spondylotic patients, and posterior compression by OYL in other cases. Myelography in flexion posture disclosed the cord compression by bony spur more clearly in two out of three spondylotic patients. Delayed CT-myelography showed intramedullary filling of contrast material in two cases, which indicated degenerative change or microcavitation due to long term compression of the spinal cord. MRI was taken in three spondylotic patients and could directly show compression of the spinal cord. Difficulty in detecting abnormality at thoraco-lumbar junction on plain roentgenogram, and similarity of the symptoms to peripheral nerve disease often lead to a delay in diagnosis. The significance of dynamic myelography and delayed CT-myelography when dealing with such a lesion was discussed here.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1988

[Clinical analysis of trigeminal neuropathy as initial manifestations--an etiological study].

The differential diagnosis of trigeminal neuropathy is quite challenging because there is a significant variety of causes for the disorder. We reviewed our cases of trigeminal neuropathy by studying first the initial manifestations in order to evaluate their underlying disorders. Sixty-four patients with trigeminal neuropathy came to our Out-Patients clinic. We have excluded from our analysis any patients with atypical pain, facial migraine, nasal sinusitis, pain from inflammation of dental pulp or facial bones, and pretrigeminal neuralgia. In 53 cases (83%) we identified the causes; 35 of them were cases of symptomatic trigeminal neuritis and 18 were trigeminal neuralgia while, in the remaining 11 cases, no definitive causative disorder was identified. Among the 35 patients with symptomatic neuritis, 10 cases were found to have malignant neoplasms including 5 cases of squamous cell carcinoma, 6 had a virus infection, 5 had traumatic origin, 4 had multiple sclerosis, 2 exhibited Tolosa-Hunt syndrome, 2 had MCTD, and there were single cases of sarcoidosis, serpentine aneurysm, cavernous sinus thrombosis, maxillary cyst and trigeminal neurinoma. The remaining 11 cases of neuritis whose causes were undetermined showed clinical features similar to trigeminal sensory neuropathy, an analogue of Bell's palsy, a benign self-limiting condition. Since the cases shared symptoms of impairment of taste, and, occasionally, of facial palsy, vestibular insufficiency, hearing disturbance, hypoglossal palsy or signs of cerebellar lesion, we strongly suspected a virus origin.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1988

[Thermographic findings of syringomyelia].

Thermographic findings in 10 cases of syringomyelia were reported. 7 cases were associated with Arnold-Chiari malformation and 3 cases with spinal adhesive arachnoiditis. The cases included 3 men and 7 women, aged 7 to 56 years (mean age 27.7 years). Comparing the right side of the body with the left side, in 9 cases, thermography demonstrated asymmetric skin temperature of the trunk or extremities. MRI revealed laterality of the syrinx at the level of cervical or lumbo-sacral cord in 9 cases. The side with the lower temperature corresponded with the side of lateralized syrinx in 8 cases. Neurologically, 9 cases had laterality of sensory disturbance and 6 cases had asymmetric motor weakness. The side with the lower temperature also corresponded with the laterality of sensory disturbance in 8 cases, and the side of the motor weakness in 4 cases. Considering these findings, many of the patients with syringomyelia are thought to have asymmetric skin temperature. Intramedullary involvement of sympathetic pathway by the syrinx may cause such a change. As thermography is non-invasive and easy to carry out, it should be a useful method for estimating or even detecting cases of syringomyelia, especially when applied to out-patients.

Adolescent↗
PubMed1988

[Treatment and prophylaxis for urogenital infections occurring after urethrocystoscopy].

To prevent urogenital infections occurring after urethrocystoscopy, we have studied the prevalence of these diseases without the use of antibiotic agents subsequent to urethrocystoscopy to determine the relative importance of aseptic procedures and whether administration of antibiotics is really required for this purpose. Patients enrolled in the present study included those undergoing urethrocystoscopy at four hospitals, totaling 146 patients (93 male and 53 female patients). All of these patients were apparently free of urogenital infections prior to urethrocystoscopy, with less than 5 leucocytes per field in urinary sediment, and a bacteria count of less than 10(4) cells/ml. Each patient was checked between 3 and 14 days after examination for 1) presence of clinical symptoms such as fever, bladder irritation symptoms and urethral secretion, 2) urinalysis and urinary culture, and 3) palpation of epididymis, testis and prostatic gland as required. The endoscope was sterilized for 20 to 30 minutes with 2% glutaraldehyde at 3 clinical institutions and with 0.5% chlorhexidine at the other, in a total of 116 and 30 patients, respectively. Sterilized distilled water was used as perfusate. The external urethral meatus of the subject was disinfected with 0.5% chlorhexidine, followed by local anesthesia with xylocaine jelly. Ten minutes after disinfecting the hands of the examiner, urethroscopy and cystoscopy were performed in this order. Urinary tract infection was detected in one male patient (1.1%) and 2 female patients (3.3%). In these cases, the endoscope was sterilized with glutaraldehyde in 2 cases and with chlorhexidine in the other. None of the subjects demonstrated fever or genital infections.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1988

[Angiomyolipoma of the kidney with regional lymph node involvement].

A 44-year-old male was admitted with complaints of gross hematuria and high fever. An excretory urogram and renal angiography revealed a massive lesion in the right kidney. A computed tomographic scan showed bilateral renal tumors with low-density areas. Transperitoneal right radical nephrectomy, regional lymph node dissection and left renal biopsy were performed on September 5, 1984. The tumor was 14.5 X 7 X 6 cm in size and yellowish in cross section. The pathological diagnosis was bilateral angiomyolipomas and the same in the right hilar lymph node and the surrounding tissue. There was no evidence of malignancy.

Adult↗