Search PubMed⌕ Search

Biomedical subjects

G Asano

Publications and source records attributed to G Asano.

At least 55 records · Page 3Linked to original sources

Expression of hsp90 and cyclin D1 in human breast cancer.

The integral roles of heat shock proteins (hsps) in the cell cycle and in multistep processes leading to tumorigenesis have been implied. We examined the expression of hsp90alpha, hsp90beta and cyclin D1 in human breast cancer. Levels of mRNAs coding for hsp90alpha and cyclin D1 were significantly higher in cancer tissues than in non-cancer tissues. Moreover, there was a close relationship between the extent of the two mRNA levels, suggesting that increased expression of hsp90alpha, an isoform of the hsp90 family, is associated with the proliferation of human breast cancer. Hsp90beta was expressed in cancer cells, but not associated with cell proliferation.

Breast Neoplasms↗

Histologic effects of ruby laser hair removal in Japanese patients.

BACKGROUND AND OBJECTIVE: Hair removal by lasers has recently become a popular method to remove unwanted hair. However, histologic changes in human skin before and after exposure to lasers have not been thoroughly investigated. The aim of this study was to clarify the differences that occur immediately after laser exposure and 1 month after laser exposure. STUDY DESIGN/MATERIALS AND METHODS: Eight adult Japanese volunteers were recruited for this study. They were treated with a long pulsed ruby laser at 20 J/cm(2). A single 3-mm punch biopsy of the laser-treated sites was obtained immediately after laser irradiation and at the 1-month follow-up visit, and they were analyzed using hematoxylin and eosin, PAM, and immunohistological staining. RESULTS: Immediately after laser exposure, hair follicles were very damaged and had extensive eosinophilic degeneration. One month after laser therapy, one type of hair follicle showed cystlike formations with negative proliferating cell nuclear antigen reactions (PCNA). Another type of hair follicle showed follicular mitotic figures with cytoplasmic halos. Early anagen hair follicles were apparently not treated effectively by ruby laser. CONCLUSION: Ruby laser leads to extensive follicular damage, and hair follicles considered to be at early anagen phase were not effectively treated. This may be the reason several courses of laser therapy are required to obtain satisfactory results.

Adult↗

Effects of quercetin and sunphenon on responses of cancer cells to heat shock damage.

Quercetin is a flavonoid well known to inhibit growth and heat shock protein (HSP) synthesis of cancer cells. However, sunphenon has been scarcely reported concerning effects on cancer cells. We compared the effects of sunphenon with those of quercetin on the human cholangio-cellular carcinoma cell line (HuCC-T1). Both flavonoids inhibited HuCC-T1 growth in a concentration-dependent manner without reduction of HSP70 and HSP90 expression before heat shock damage. The heat shock reduced the cell viability of the quercetin-treated HuCC-T1, but not that of the sunphenon-treated cells. This inhibitory effect of quercetin on tolerance to heat shock is thought to be due to marked suppression of HSP72. Sunphenon conversely increased HSP72 expression after heat shock. Although neither flavonoid altered HSP90 protein levels before and after heat shock, quercetin delayed the reorganization of filamentous actin (F-actin) during the recovery period after heat shock. Since HSP90 could preserve F-actin structure during stresses, quercetin might affect the interaction between HSP90 and F-actin without influencing HSP90 expression. In conclusion, quercetin would be more useful than sunphenon in combined therapy with hyperthermia for cancer.

Anticarcinogenic Agents↗

Ultrastructural characteristics of myocardial and coronary microvascular lesions in Kawasaki disease.

Kawasaki disease (KD) is an acute febrile mucocutaneous lymph node syndrome with multisystemic vasculitis affecting mainly infants and children. Although several studies on cardiovascular lesions in KD have been done at the light microscopic level, the ultrastructural characteristics and incidences of these lesions have not been well defined. In order to investigate the myocardial and coronary microvascular sequelae in KD, we performed an ultrastructural study on endomyocardial biopsy specimens obtained during follow-up from 54 patients who had typical clinical manifestations of KD, of whom 47 had associated coronary aneurysms as demonstrated by coronary arteriography (CAG) or two-dimensional echocardiography in the acute or healed stage. The average age of onset was 2.2 years old and the duration of illness was from 2 months to 23 years. Follow-up CAG showed that the coronary aneurysms persisted in 33 of the 47 patients (8 with associated stenosis) and resolved in the remaining 14 patients. Ultrastructurally, the myocardial changes revealed hypertrophy, various degrees of degeneration, proliferation and abnormality of mitochondria, infiltration of a small number of lymphocytes, and fibrosis. The coronary microvascular lesion was characterized by microvascular dilatation, endothelial cell injury, platelet aggregation with thrombosis, and stenotic lumen with thickened walls in the small arterioles. It persisted after convalescent stage even up to 23 years and closely correlated with the myocardial sequelae. Moreover, significantly increased incidences of myocardial and coronary microvascular lesions were found in patients with coronary artery lesion. These findings suggest the coronary microvascular lesion as a possible underlying factor of persistent sequelae in KD.

Adolescent↗

Expression of cathepsin B and cystatin C in human colorectal cancer.

Cathepsin B is a matrix protease that may be associated with colorectal carcinoma invasion and progression. In this study, we investigated the localization of cathepsin B in cancerous and noncancerous tissues of 80 patients with colorectal cancer including 25 cases with liver metastasis. In addition, the expression of cystatin C, one of several cathepsin B inhibitors, was compared with that of cathepsin B in the same samples to reveal one of the regulation mechanisms of cathepsin B. The cancer cells in the advancing edge of the tumors often exhibited the strongest immunostaining of cathepsin B, and stromal cells and normal epithelial cells adjacent to the tumors were also positive for cathepsin B. The percentage of cathepsin B-positive cases was significantly larger in the group with liver metastases than in the group without liver metastases. In the group without liver metastases, the cancer cells and stromal cells more frequently exhibited cathepsin B immunoreactivity in Dukes' A cases than in Dukes' B and C cases. In situ hybridization and reverse transcription-polymerase chain reaction (RT-PCR) confirmed cathepsin B synthesis in the cancer and proximal epithelial cells. There was an average 3.7-fold increase in cathepsin B mRNA levels in the cancerous tissues compared with that of noncancerous tissues, and Dukes' A tumors exhibited the highest expression level. Conversely, cystatin C mRNA levels were similar in all samples, and tended to show an inverse correlation with the cathepsin B levels. In conclusion, cathepsin B expression by human colorectal cancers and surrounding noncancerous cell components may contribute to both local invasion at the early stage and remote metastasis without influence of cystatin C.

Adenocarcinoma↗

Thyroid papillary carcinoma arising in ectopic thyroid tissue within a branchial cleft cyst.

A case of papillary carcinoma arising in ectopic thyroid tissue within a branchial cleft cyst is described. A 46-year-old woman presented with a 2.0 x 2.0 cm mass in her left lateral neck. The excised mass showed a cystic lesion with a thyroid papillary carcinoma. Following a lateral cervical cystectomy, subsequent thyroid gland and lymph nodes dissections were performed. Pathological examination showed an adenomatous goiter and no primary carcinoma in the thyroid gland, as well as metastatic papillary carcinoma in the lymph nodes. Two cases of thyroid papillary carcinoma arising in ectopic thyroid tissue within a branchial cyst have been reported previously, but no lymph node metastases were recognized. The first case of papillary carcinoma arising in ectopic thyroid tissue within a branchial cleft cyst, and accompanied by lymph node metastasis is presented.

Adenoma↗

Ossifying fibromyxoid tumor of soft parts: clinicopathologic, immunohistochemical and ultrastructural study of four cases.

Four cases of uncommon soft tissue tumors were investigated histopathologically. All of them consisted of fibrous and myxoid components, and mature bone showed shell-like characteristics. Histological features revealed these tumors were well circumscribed by a thick collagenous fibrous capsule and composed of uniform-sized fusiform cells with eosinophilic cytoplasm and a round or oval nucleus in the myxoid matrix. An incomplete shell of mature bone with lamellar structure was also observed at the periphery. Immunohistochemical and ultrastructural studies were performed. The major component of the proliferating cells in the tumors had positive staining for vimentin, S-100 protein, neuron-specific enolase and synaptophysin. The myxoid matrix was stained by alcian blue and was digested completely by pretreatment with hyaluronidase. Electron microscopy showed the cytoplasm contained dense-core granules measuring 100-200 nm and abundant filaments of an intermediate size. It is suggested that these uncommon tumors might be diagnosed as the 'ossifying fibromyxoid tumor of soft parts' previously described by Enzinger et al., which were derived from peripheral nerve sheath tumors such as neurofibroma and myxoid neurofibroma.

Adult↗

Time course of expression and localization of heat shock protein 72 in the ischemic and reperfused rat heart.

While the role of heat shock protein 72 (HSP72) in protection of the ischemic heart has been studied extensively, the expression and localization of HSP72 in the ischemic and reperfused heart remains poorly understood. This study examined the expression and distribution of HSP72 after various periods of ischemia and reperfusion in the non-stress-pretreated rat heart. The distribution of HSP72 in the myocardium was examined immunohistochemically using a specific monoclonal antibody for detection of this protein. The levels of HSP72 mRNA in the myocardium were estimated by the reverse transcriptase polymerase chain reaction (RT-PCR) method. Rats were subjected to either permanent occlusion of the left coronary artery or 30 min of occlusion followed by reperfusion, and they were sacrificed 30 min, 4 h, 24 h and 7 days thereafter. Both permanent ischemia and reperfusion induced expression of HSP72 mRNA in the ischemic myocardium from 30 min to 24 h after the onset of ischemia/reperfusion. The maximum mRNA level, which appeared at 4 h, was much higher in the reperfusion group than in the permanent ischemia group. Myocytes exhibited definite immunoreactivity of HSP72 at 4 h and 24 h in both groups, and microvessels exhibited strong immunoreactivity at 4 h in the reperfusion group. This study revealed the time course of expression and distribution of HSP72 in the ischemic and reperfused hearts in vivo.

Animals↗

Ultrastructural changes and immunohistochemical localization of nitric oxide synthase, advanced glycation end products and NF-kappa B in aorta of streptozotocin treated Mongolian gerbils.

To evaluate the relationship among the induction of nitric oxide synthase (NOS), advanced glycation end products (AGEs) and NF-kappa B for vascular damage in hyperglycemia, we injected Mongolian gerbils intravenously with 150 mg/kg streptozotocin (STZ) and observed over the next one year the resulting aortic changes by immunohistochemical and electron microscopical techniques. After STZ treatment, hyperglycemia was confirmed and body weight transiently decreased. Morphological observation revealed no remarkable changs in vascular endothelial cells or vascular smooth muscle cells in the aorta at one week after STZ administration. After 4 weeks increased collagen fibrils were observed in the pericellular spaces of media. At one year after STZ administration, increased collagen fibrils and thickened elastic fibers were found around the vascular smooth muscle cells with vacuolization and increased cytoplasmic organellae compared with non-treated animals of the same age. Immunohistochemically endothelial constitutive NOS (ecNOS) was localized in the endothelium of the aorta of Mongolian gerbils. At one year after STZ administration, the reaction products of iNOS, AGEs and NF-kappa B in vascular endothelial cells and smooth muscle cells were much more greatly increased than at one week and 4 weeks. After STZ administration, the localization of NOS, AGEs and NF-kappa B was observed in the aorta, which suggests these factors play important roles in the pathogenesis of vasculopathy in diabetes mellitus.

Animals↗

[The relationship between p53 protein and c-erb B-2 expression and apoptosis in colorectal cancer].

In order to elucidate the relationship between tumor growth and various kinds of gene expression and the occurrence of apoptosis in the front portion of neoplastic invasion, 57 advanced colorectal cancers were studied by immunohistochemical staining of p53, c-erb B-2, the TUNEL method and electron microscopy. Light microscopically, the columnar epithelial cells of adenocarcinoma frequently showed a decrease in high and a fall off into the lumen in tumor invasive forefront. Immunohistochemically the positive rate of p53 and c-erb B-2 in tumors with high vascular invasion were higher (p < 0.05) than in those with low vascular invasion. There was a close correlation between the vascular or lymphatic invasion and positive immunoreactivity of p53 and c-erb B-2. The apoptosis index was demonstrated to be related to vessel invasion, over expression of p53 and inflammatory cell infiltration around the front portion of the tumor invasion. These results suggested that p53. c-erb B-2 and the apoptosis index should be evaluated in conjunction with the prognostic factors in colorectal cancer. The infiltrative inflammatory cells may induce apoptosis of the tumor cells.

Adult↗

Brief survey of leprosy situation in Congo: sero-epidemiologic profile in correlation with some emerging viral infections.

The Democratic Republic of Congo (DRC, former Zaire) in central Africa remains the foremost country for leprosy in Africa, with a total of 4877 registered cases, of which 4573 are new cases since 1997. These numbers are well above the regional average. About 94% of these patients are under multidrug therapy (MDT) coverage in the Congo, which ranks 8th in coverage rate among the surrounding nine nations. Available data on anatomo-clinical profile and bacillarity are provided, with reservations on the use of these data drwn due to relatively small sample sizes. The seroprofile of the disease was reviewed with regard to the association of other immunity impairing infections like HBV infection and the recently highly incident retroviral epidemics (HIV-1, HTLV-1, and HTLV-2). The leading role of non-governmental organizations is cited for improving leprosy patient conditions and also for future prospects, where the necessity of coordinated strategies with the government is emphasized. Recommendations for new trends and steps relevant to improving existing and future leprosy control strategies are put into perspective.

Communicable Disease Control↗

Fluorescence spectroscopic and histochemical analysis using hematoporphyrin as a microenvironmental probe for atherosclerotic change in the human aorta.

Hematoporphyrin (HP) was used as a microenvironmental fluorescent probe to investigate the development of human atherosclerotic plaques. We compared the site of HP accumulation with changes in the HP fluorescence spectrum in atheromatous plaques and in a liposome control model, using a confocal laser scanning microscope equipped with a photonic multi-channel analyzer linked to a fluorescence spectrometer. Wavelength shifts of the two peaks of HP fluorescence (F1, 620 nm; and F2, 640-690 nm) were monitored, and the integrated F2/F1 ratio was calculated as a measure of HP fluorescence. The F1 peak is characteristic of a predominantly aqueous site. The ratio reflects selective changes in the distribution and overcrowding of HP molecules in the limited space of the artificial membrane model. Compared with a normal artery, the atherosclerotic lesions showed an increase in the area of HP fluorescence, increased fluorescence intensity, a red shift of the HP fluorescence spectrum, and an increased F2/F1 ratio. The F2/F1 ratio of the membranous structures was markedly greater in the cores of the fibrous plaques than in the other plaques. The F1 peak showed increased intensity in the atheromatous plaque core, whereas in hydrophilic fibrous regions, such as the cap of the plaque, the intensity of the F1 peak was lower than in the core region. HP aggregation was observed in damaged cells and in water surrounded by lipid in the atheromatous core. Using HP as a probe allowed us to determine not only the ionization or polarity of each region in the atherosclerotic plaques but also to detect the separation and fusion of the lipid bilayer or micelle lipids, as well as damage to the cellular membranes and cholesterol enrichment. These findings suggest that HP is useful for detecting clinically important changes in atherosclerotic lesions, to lipid-rich, unstable, and vulnerable plaques, which are closely associated with cardiovascular events.

Adult↗

[Expression of endothelial nitric oxide synthase and inducible nitric oxide synthase in synovium of rheumatoid arthritis].

OBJECTIVES: To examine the localization and distribution of endothelial nitric oxide synthase (eNOS) and inducible nitric oxide synthase (iNOS), which participate in nitric oxide (NO) production, in synovium of rheumatoid arthritis (RA). MATERIALS AND METHODS: Immunohistochemical analysis for eNOS and iNOS in synovial tissues obtained from 10 patients with RA who were underwent total knee replacement. Synovial tissues of osteoarthritis (OA) were used as control. The percentage of cells that were positive for eNOS and iNOS was estimated in five hundred endothelial cells, synovial lining cells and interstitial cells, respectively. And mRNA expression of NOS was confirmed by in situ hybridization. In addition, to test NO production, nitration of tyrosines was assessed by immunohistochemistry. RESULTS: Not only endothelial cells but also synovial lining cells and interstitial cells exhibited immune-reactive both eNOS and iNOS. Cells which were seemed immune-reactive eNOS and iNOS expressed nitrotyrosin. By in situ hybridization, we detected mRNA expression for eNOS and iNOS. CONCLUSIONS: Endothelial cells, synovial lining cells and interstitial cells expressed both eNOS and iNOS with high frequency in RA synovium compared with OA synovium. It seemed to correlate with NO production. These results suggest that expression of iNOS may be involved in the induction of arthritis and eNOS may be participated in augmentation of inflammation in RA.

Arthritis, Rheumatoid↗