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T Akashi

Publications and source records attributed to T Akashi.

At least 73 records · Page 4Linked to original sources
PubMed1997

Histological differentiation and basement membrane distribution in gastric adenocarcinomas.

To analyse the histological distribution of basement membranes (BM) in gastric adenocarcinomas, we produced a monoclonal antibody, BM909 (IgG 2b, kappa), which has been found useful for identifying the BM in routinely processed specimens. The BM 909 antibody was shown by ELISA to be negative against the three major BM components (type IV collagen, laminin and fibronectin). Gastric carcinomas from 78 patients including both differentiated and undifferentiated adenocarcinomas were classified into three types (tubular, trabecular, and isolated) based on the histological arrangement of the cancer cells. Histological distributions of the BM were also classified into four patterns (peritubular, peritrabecular, intratrabecular, and pericellular) based on the immunostaining results with the BM 909 antibody. Our results demonstrated a close relationship between these two parameters as follows: 1) the tubular type of gastric carcinomas showed a peritubular pattern of BM distribution in the differentiated adenocarcinomas; 2) The isolated type of gastric carcinomas showed a pericellular pattern of BM distribution in the undifferentiated adenocarcinomas; and 3) The trabecular type of gastric carcinomas showed either peritrabecular or intratrabecular patterns of BM distribution, in both differentiated and undifferentiated adenocarcinomas. In conclusion, we suggest that all gastric adenocarcinomas are accompanied by BM deposition regardless of the degree of histological differentiation.

Adenocarcinoma↗
PubMed1996

Persistence of multipotent progenitors expressing AML1/ETO transcripts in long-term remission patients with t(8;21) acute myelogenous leukemia.

The leukemia-specific AML1/ETO fusion gene has been shown to be detected by reverse transcriptase polymerase chain reaction (RT-PCR) analysis in patients with t(8;21) acute myelogenous leukemia (AML) in long-term remission. In the present study, the AML1/ETO mRNA could be detected by RT-PCR in bone marrow (BM) and/or peripheral blood (PB) samples from all 18 patients who had been maintaining complete remission for 12 to 150 months (median, 45 months) following chemotherapy or PB stem cell transplantation (PBSCT), whereas it could not be detected in four patients who had been maintaining remission for more than 30 months following allogeneic BM transplantation (BMT). We surveyed the expression of AML1/ETO mRNA in clonogenic progenitors from BM in these cases. Notably, 51 of 2,469 colonies from clonogenic progenitors (2.1%) expressed the AML1/ETO mRNA in 18 cases who were RT-PCR+ in BM and/or PB samples. Expression was observed in various clonogenic progenitors, including granulocyte-macrophage colonies, mixed colonies, erythroid colonies, and megakaryocyte colonies. Furthermore, we analyzed the clonality of these progenitors by X-chromosome inactivation patterns of the phosphoglycerate kinase (PGK) gene in four female patients. The AML1/ETO mRNA+ progenitors showed the PGK allele identical to that detected in the leukemic blasts from the time of initial diagnosis. Normal constitutive hematopoiesis was sustained by polyclonal BM reconstitution in these patients. Accordingly, these committed progenitor cells that express AML1/ETO mRNA during remission likely have arisen from common t(8;21)+ pluripotent progenitor cells with at least trilineage differentiation potential. These data strongly suggest that the origin of the clonogenic leukemic progenitors of t(8;21) AML may be multipotent hematopoietic progenitors that acquired the t(8;21) chromosomal abnormality.

Adult↗
PubMed1996

Gonadotropin therapy in males with hypogonadotropic hypogonadism: factors affecting induction of spermatogenesis after gonadotropin replacement.

Sixteen patients with hypogonadotropic hypogonadism received gonadotropin replacement therapy. Two patients treated with HCG alone showed induction of spermatogenesis 2 and 12 months after the start of treatment. Three subjects receiving combination therapy showed sperm appearance 6-28 months after treatment. The patients showing sperm appearance, whose testicular volume was > or = 4 ml, showed a higher sperm count and impregnated their partners, although no relationship was found between pretreatment testicular volume and sperm appearance. The response to HCG test correlated with sperm appearance after gonadotropin therapy. Sperm appearance was not observed in any subject except for one who showed no response to luteinizing hormone-releasing hormone (LH-RH) test and none of the patients without response of FSH to LH-RH demonstrated any induction of spermatogenesis. In conclusion, the responses to LH-RH test and possibly to HCG test could predict the induction of spermatogenesis after gonadotropin replacement therapy, and a large testicular volume is associated with post-treatment fertility.

Adolescent↗
PubMed1996

Quantitative determination of tautomeric FK506 by reversed-phase liquid chromatography.

The quantitative determination of FK506, an immunosuppressant for organ transplants, was studied by using reversed-phase high performance liquid chromatography. There were three peaks corresponding to FK506 and its tautomeric compounds on the chromatogram obtained from aqueous solution. Interconversion among these compounds due to epimerization occurs and then reaches an equilibrium in aqueous solution. An increase in the water content in water-solvent solutions caused by the peak areas of FK506 and Tautomer I to decrease and that of Tautomer II to increase. For quantitative analyses of aqueous solutions this creates a problem because the composition of the mixture at equilibrium varies with the water content. A simple method, using a solution of polyoxyethylene lauryl alcohol ether (Brij-35) as a diluent, has been developed to provide a constant equilibrium. By diluting the sample with the Brij-35 diluent, it is possible to quantify FK506 in aqueous solutions. The reliability of the proposed method was confirmed with samples extracted from fermentation broth.

Chromatography, High Pressure Liquid↗
PubMed1996

[MRI findings of hyperostosis frontalis interna--a case of Morgagni syndrome].

We report a patient with Morgagni syndrome. The main aim of this paper is to discuss hyperostosis frontalis interna (HFI) and coexisting clinical feature and to describe the pathomorphology in detail on the basis of MRI images of the skull. The patient, a woman, was 82 years old when she first came to our hospital. She had a 20-year history of hypertension and chronic headache, and had been excessively obese till three years before. On admission she presented with a broad spectrum of clinical symptoms and signs including insomnia, disorientation to place, loss of memory, dementia, night delirium, reduced deep tendon reflexes in the lower extremities, urinary incontinence and upward gaze palsy. Because of a fair recovery within several days, it was suspected that so-called "treatable dementia" played a considerable role in the above-mentioned clinical state. Laboratory testing data, including hormone levels, were all within normal limits. EEG examinations showed slowed, diffuse, and poorly developed alpha-waves with no paroxysms. Cranial CT in horizontal sections disclosed a deformed frontal bone with convexlens-shaped thickening bilaterally and diffuse high density on both sides. MRI images revealed more detailed structures: the outer plate, diploe and inner plate of the skull, and abnormal ossifications. Based on these findings we diagnosed her illness as Morgagni syndrome. Recent reports, though few in number, have tended to focus on the EEG findings, hormones and psychiatric states in this syndrome, and descriptions of the HFI itself seem to be rare. The true cause of this syndrome is not yet known, so this rare presentation of MRI images of HFI is thought to be important in explaining this peculiar phenomenon in the skull.

Aged↗
PubMed1996

[Serum concentration of pyridinoline cross-linked carboxy-terminal telopeptide of type-I collagen (ICTP) and carboxyterminal propeptide of human type I procollagen (PICP) in the diagnosis of bone metastases].

Recently discovered bone metabolic markers are expected to play an additional role in the diagnosis of bone metastasis. We measured bone metabolic markers, serum pyridinoline cross-linked carboxy-terminal telopeptide of type I collagen (ICTP) and carboxyterminal propeptide of human type I procollagen (PICP) in 224 patients with breast cancer (106 with bone metastases), 61 patients with prostatic cancer (30 with bone metastases), 45 patients with lung cancer (17 with bone metastases) and 13 patients with miscellaneous cancers (7 with bone metastasis) and compared the values in the presence and absence of bone metastasis. ICTP and PICP increased significantly in patients with bone metastases. By the analysis of sensitivity and specificity, the cut-off levels were considered to be 5.0 ng/ml for ICTP and 140 ng/ml for PICP. In lung cancer (bone metastases are mostly of osteolytic), ICTP was excellent marker in detecting bone metastasis. In breast cancer (bone metastases are mostly of mixed type), ICTP was good in detecting bone metastases. In prostatic cancer (bone metastases are mostly of osteoblastic), ICTP and PICP were good markers in detecting high grade of bone metastases. Over all, ICTP was more sensitive in the diagnosis of bone metastases than PICP. However, both markers were not effective in detecting low grade bone metastases. ICTP and PICP should play a supportive role to imaging modalities in the diagnosis of bone metastases.

Aged↗
PubMed1995

Effects of (-)-epigallocatechin-3-O-gallate (green tea tannin) on the life span of stroke-prone spontaneously hypertensive rats.

1. Effect of (-)-epigallocatechin-3-O-gallate (EGCG), a condensed tannin isolated from green tea leaves, on the life span and hypertensive lesions in the stroke-prone spontaneously hypertensive rat (SHRSP) was compared with that of persimmon tannin. 2. Long-term administration of either 0.5% EGCG or 0.5% persimmon tannin to SHRSP inhibited the incidence of stroke and prolonged the life span, but did not affect the blood pressure. 3. These results indicate that EGCG may prevent incidence of stroke due to the radical scavenging action and inhibition of lipid peroxidation, and may result in prolonging the life span of SHRSP, as in the case of persimmon tannin.

Animals↗
PubMed1995

Anti-inflammatory effect of flurbiprofen tape applied percutaneously to rats with adjuvant-induced arthritis.

The anti-inflammatory effect of flurbiprofen tape (FP-T) by topical application was investigated, and the findings were compared with the results of oral administration of flurbiprofen to adjuvant arthritic rats. The topical application of FP-T significantly suppressed both applied and non-applied hind paw edema, with a potency similar to that seen with the oral administration of flurbiprofen. Body weight also increased with these treatments. Plasma levels of flurbiprofen differed little between topical application of FP-T and oral administration of flurbiprofen. Gastric damage induced by topical application of FP-T was significantly less than that seen in case of oral administration of flurbiprofen. These results suggest that the anti-inflammatory effects of FP-T cannot be entirely explained by flurbiprofen permeating inflamed tissue below the application site; rather, flurbiprofen penetrating into the systemic circulation may explain these actions.

Administration, Topical↗
PubMed1995

Histopathological and immunohistochemical analysis of adenomatous hyperplasia and hepatocellular carcinoma: cellularity, thickness of cell cord, and Ki-67 proliferative activity.

To characterize adenomatous hyperplasia (AH) and hepatocellular carcinoma (HCC), and to establish their histopathological differences, morphometrical and immunohistochemical analyses, namely, cellularity, thickness of cell cord, and Ki-67 labeling index (Ki-67 LI) were done on surgically obtained hepatic lesions from patients with positive serum antibody against HCV. The hepatic lesions analyzed include chronic active hepatitis (CAH) (11 specimens), regenerative nodules of liver cirrhosis (LC) (29), AH (11), small HCC Edmondson's Grade I (GI) (19), GII (26), GIII (14). The results showed that AH has relatively high cellularity, and significantly greater thickness of cell cord than LC; whereas, HCC GI has significantly higher cellularity and Ki-67 LI than AH. From the data of these markers, and from the absence of conspicuous structural atypism, AH is considered to be in a different category from HCC GI. The premalignant potential of AH is supported only by its high incidence of coexistence adjacent to HCC GI or GII(6/11). Most lesions of HCC seem to develop from the liver tissue having a background of CAH or LC without passing through AH. Focal fatty changes are frequently observed within lesions of both AH and HCC GI (5/11, 8/19). When non-fatty regions of AH and HCC GI are compared, with respect to their markers, particularly Ki-67 LI, as well as the structural atypism, such as microacinus formation and pseudoglandular structure, and invasive growth into the surrounding liver parenchyma, HCC GI can be diagnosed as an early or well-differentiated malignant lesion.

Adenoma↗
PubMed1994

Effects of capsaicin on mechanoenergetics of excised cross-circulated canine left ventricle and coronary artery.

Capsaicin selectively acts on sensory nerve endings in cardiac muscles and coronary arterial smooth muscles. Capsaicin at high doses has cell-nonselective effects including both inhibition of cardiac muscle exciteability and enhancement of vascular smooth muscle tone. We studied whether and how intracoronary infusion of capsaicin affects mechanoenergetics of the excised blood-perfused canine heart and coronary vascular resistance. We found that capsaicin at low concentrations increased Emax (a contracility index) and oxygen consumption (VO2) possibly due to a specific action on capsaicin-sensitive sensory nerves in left ventricular muscles, though in a small number of hearts (3/10). This result coincides with the reported histochemical observations that the distribution of capsaicin-sensitive sensory nerves in the canine left ventricle is not dense. Capsaicin at high doses dose-dependently decreased Emax and proportionally decreased coronary flow. It also lowered the linear VO2-PVA (pressure-volume area; total mechanical energy) relationship without a change in the slope, decreasing unloaded VO2 (VO2 intercept of the VO2-PVA relation). These effects of high-dose capsaicin seem to be direct negative inotropic action on cardiac muscles associated with enhancement of coronary arterial smooth muscle tone, since these effects were not desensitized. No morphological changes of myocardial cells or mitochondria were detected. Therefore, the negative inotropic action is not due to the toxic effect of capsaicin.

Animals↗
PubMed1994

Gene expression of CD24 core polypeptide molecule in normal rat tissues and human tumor cell lines.

CD24 antigen is a glycoprotein expressed on haematopoietic cells, including B cells, T cells and granulocytes and on non-haematopoietic cells, including neural cells, ganglion cells and the cells of the adrenal medulla. The antigen is also expressed on renal cell carcinoma, small cell lung carcinoma and neuroblastoma. We have cloned rat cDNA encoding core polypeptide of CD24 antigen from embryonic brain and shown that the core molecule is highly expressed in embryonic brain and non-neural tissues. Rat tissue and various human neoplastic cell lines were investigated for the gene expression of CD24 core polypeptide by in situ hybridization. The transcript was localized in gastrointestinal epithelia, ductal and acinar epithelia of the salivary gland, the bronchiolar epithelium, renal tubular epithelium, the epithelium of the oviduct, follicular cells of the thyroid, medullary cells of the adrenal gland, Auerbach's plexus, B blastoid cells in lymph nodes, hair follicles, and the sweat glands of the skin. Among the various human neoplastic cell lines investigated, the transcript was detected in squamous cell carcinoma of the lung, gastric carcinoma, colon carcinoma, choriocarcinoma and renal cell carcinoma. The result suggest that the core molecule of CD24 antigen may be expressed in a wider range of epithelial cells and carcinoma cell lines than has been reported. Furthermore, we show that gene expression of CD24 core polypeptide is confined to the proliferative zone of the gastrointestinal mucosa, suggesting that core molecule is transiently expressed on the surface of epithelial cells in the process of cellular maturation. We discuss a possible role for CD24 antigen in the maturation of epithelial cells in the gastrointestinal tract.

Animals↗
PubMed1994

The role of the cytoskeleton in the polarized growth of the germ tube in Candida albicans.

Cells of the dimorphic yeast Candida albicans are easily induced to germinate in synchrony. Using germinating cells of strain FC18, we examined the effects of several drugs that are known to affect the cytoskeleton on growth and cytoskeletal organization. Cytochalasin A (CA), an inhibitor of actin function, inhibited the germination of the yeast cells and changed the cylindrical expansion of the apex of the germ tube to swelling growth. Effects of CA on the organization of actin were examined with rhodamine-phalloidin (Rh-Ph), which specifically stains F-actin. In CA-untreated cells, Rh-Ph staining resulted in condensed dot-like fluorescence at the growing tip, as well as filamentous fluorescence (actin cables) that ran from the apex to the basal region. In CA-treated cells, condensed dot-like fluorescence was still observed at the swelling tip, but actin cables had disappeared completely. This result indicates that CA does not affect the asymmetrical distribution of actin, and suggests that the actin cables are not required for maintenance of the polarized localization of actin. Benomyl, an anti-microtubule drug, inhibited the germination of yeast cells and the apical growth of germinated cells. Benomyl not only disrupted microtubules (MTs), but also affected the distribution of actin. In benomyl-treated cells, actin dots were randomly dispersed all over the cell. This result indicates that benomyl destroyed the mechanism that maintains the asymmetrical distribution of actin, and suggests that MTs are involved in such a mechanism. The polarized localization of organelles is one of the most important factors associated with dimorphism.(ABSTRACT TRUNCATED AT 250 WORDS)

Actin Cytoskeleton↗
PubMed1994

Estimation of total carbon dioxide contents in canine coronary arterial and venous whole blood samples.

We examined whether total carbon dioxide content (CCO2) estimation equations for human whole blood in the literature are applicable to canine coronary arterial and venous blood samples. PCO2 of the tested blood samples covered 19-52 mmHg; PO2 19-398 mmHg. Three CCO2 estimation equations developed by Kelman, Godfrey, and Douglas et al yielded CCO2 values over a range of 26.7-54.9 vol%, where plasma CCO2 values calculated by the Henderson-Hasselbalch equation ranged over 27.7-62.2 vol%. The estimated blood CCO2 values were almost identical among the three equations. They also closely correlated with plasma CCO2 values measured after hemolysis with saponin. We conclude that the human whole blood CCO2 estimation equations are applicable to canine coronary arterial and venous blood samples. These CCO2 equations may be used for canine cardiac metabolic studies.

Animals↗
PubMed1994

Changes in the distribution of F-actin in the fission yeast Schizosaccharomyces pombe by arresting growth in distilled water: correlative studies with fluorescence and electron microscopy.

Freeze-substitution electron microscopy of Schizosaccharomyces pombe cells starved in distilled water was conducted to define ultrastructural counterparts of actin visualized by fluorescence microscopy using rhodamine-conjugated phalloidin (Rh-ph). Starvation in distilled water caused remarkable changes in actin distribution and ultrastructural changes in S. pombe. Fluorescence microscopy of the starved cells showed that the dots of actin at the growing ends became thick actin cables via an enlarged patched form of actin. These changes were reversible, and growth-arrested cells resumed their original pattern of actin distribution upon return to growth medium. Electron microscopy of starved cells showed bundles of thin filaments and clusters of filamentous balls in the cytoplasm, which corresponded to the actin cables and enlarged actin dots, respectively, as seen by fluorescence microscopy. Vesicles polarized at the growing cell ends were dispersed in the cytoplasm by distilled water treatment, indicating that actin organization plays a role in directing vesicle location.

Actin Cytoskeleton↗
PubMed1994

[Investigation of involvement of cerebral white matter in DRPLA--including MRI perfusion study].

Clinical, radiological, and histological examinations were performed on eight patients with autosomal-dominant dentato-rubro-pallido-luysian atrophy (DRPLA) including an autopsy case, to investigate the abnormal findings of the cerebral white matter in DRPLA. Three of the eight patients were found to have diffuse low density on CT or diffuse high-signal areas on T2-MRI in the white matter of the brain. There were no correlations between abnormal findings in the white matter and the following factors; age of onset, duration of the disease, clinical manifestations, disease severity, Hachinski score, or EEG abnormality. Single-photon emission tomography failed to reveal any relative decrease in cerebral blood flow in the white matter, even in the three patients with abnormal findings in the white matter. MRI perfusion studies did not suggest any decrease in cerebral blood volume in any of the patients examined, but in the DRPLA patients the latency, i.e., the interval from the time of injection to the time of the minimum signal intensity, was significantly prolonged in comparison with the results in normal controls. On histopathological investigation, there was diffuse decreased staining in the centrum semiovale and deep white matter of the temporal lobes bilaterally, but no gliosis, or arteriolar thickening or hyalinization were detected. These findings confirmed that the lesions in the white matter in DRPLA are not attributable to cerebral ischemia. The abnormal findings are presumably the result of the degeneration which occurs in DRPLA itself.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗