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Y Takano

Publications and source records attributed to Y Takano.

At least 235 records · Page 13Linked to original sources

Prognostic significance of Ki-67 labeling index in urothelial tumors of the renal pelvis and ureter.

PURPOSE: We evaluated the prognostic significance of the Ki-67 labeling index in 70 patients with primary urothelial tumors of the renal pelvis and ureter. MATERIALS AND METHODS: Immunohistochemical staining for Ki-67 in archival tumor materials was done by the streptavidin-biotin method. RESULTS: Univariate survival analysis showed that the prognosis of patients with a high Ki-67 labeling index of 21.7 or more was significantly worse than that of patients with an intermediate labeling index of 13.3 to less than 21.7 (p < 0.01) or a low labeling index of less than 13.3 (p < 0.001). Multivariate survival analysis showed that staining for Ki-67 labeling index was significantly correlated with prognosis (p < 0.01). CONCLUSIONS: Analysis of Ki-67 labeling index provides useful prognostic information about patients with primary urothelial tumors of the renal pelvis and ureter.

Antigens, Neoplasm↗

Advantages of raloxifene over alendronate or estrogen on nonreproductive and reproductive tissues in the long-term dosing of ovariectomized rats.

For the first time, raloxifene or alendronate was administered to rats immediately after ovariectomy for 10 months and compared with estrogen to elucidate mechanisms behind the raloxifene effects observed in nonreproductive and reproductive tissues. Specifically, 75-day-old rats were randomly selected as sham controls (Sham), ovariectomized controls (Ovx) or ovariectomized rats treated with fully efficacious doses of raloxifene (RA), 17 alpha-ethynyl estradiol (EE2) or alendronate (ABP). Lumbar vertebrae and proximal tibiae were examined by computed tomography (QCT) and by histomorphometry. Histomorphometry showed differences in bone architecture between groups when QCT densities were similar, but tibial trabecular bone analysis by QCT correlated with histomorphometry with r = .86 to .93, depending on the parameter. Both techniques confirmed that Ovx had substantially less bone than Sham, with greater loss of trabecular bone in the proximal tibia than vertebrae. Both techniques showed that RA had effects similar to but not identical with EE2 in preventing bone loss in vertebrae and tibiae. ABP partially prevented loss of bone in L-5, but was not significantly different from Ovx in the proximal tibia. This may be caused by ABP suppression of bone apposition, beyond effects observed for EE2 or RA. RA appeared to be more similar to EE2 because ABP significantly depressed bone formation (bone formation rate, mineral apposition rate) to below RA or EE2 levels, especially in L-5. Mechanical loading to failure of L-6 vertebrae showed a rank order of vertebral strength of Sham > RA > EE2 > Ovx > ABP, although significant differences were not observed between treatment groups. These data show that ABP suppression of bone formation can affect bone quality with long-term treatment. In other tissues, RA had minimal uterine effects, while significantly lowering serum cholesterol to below EE2-treated levels. Both EE2 and RA rats had significantly lower body weights than the other groups. ABP had no effect on serum lipids, uterine weight or body weight. Therefore, RA appears to have a broader range of desirable effects on bone, body weight, uteri and cholesterol than ABP or EE2 in ovariectomized rats.

Alendronate↗

[Cyclic alteration in atheroma plaque morphology observed by intracoronary ultrasound: initiation mechanism of acute myocardial infarction].

Rupture of plaque is an important factor in the initiation of acute myocardial infarction. Plaque rupture is related to stress distribution in atheroma, but morphological alteration in coronary atheroma plaque in vivo is little understood. Atheroma plaque was observed during the cardiac cycle using 3.5 or 2.8 F, 30 MHz intracoronary ultrasound (ICUS) in seven patients with coronary artery disease. Coronary ostial pressure (P) measurements were simultaneously performed. Seven of the eccentric stenotic sites were analyzed. Intima-medial thickness (Th) and regional radius of curvature (R) at the middle and lateral portions of the atheroma were measured. Delta Th and % delta Th were calculated from change in thickness from end-diastole to peak systole. These parameters of the middle portion were compared with those of the lateral portion. The lateral % delta Th was 20.1 +/- 13.6% (delta Th 0.13 +/- 0.08 mm; 0.69 to 0.56 mm), and was significantly greater than the middle % delta Th [5.8 +/- 6.6% (delta Th 0.06 +/- 0.08 mm; 1.24 to 1.18 mm), p < 0.05]. Regional radius of curvature did not significantly differ. Wall stress calculated as P x R/Th was greater at the lateral portion (peak systole 3.7 x 10(5) dynes/cm2, end-diastole 1.9 x 10(5) dynes/cm2) than at the middle portion (peak systole 1.4 x 10(5) dynes/cm2, end-diastole 0.9 x 10(5) dynes/cm2). The change in stress from end-diastole to peak systole at the lateral portion was significantly greater (1.8 x 10(5) dynes/cm2) than that at the middle portion (0.5 x 10(5) dynes/cm2). The change in stress during the cardiac cycle, caused by the increase in intracoronary pressure, was greater at the lateral than at the middle of the plaque. This imbalanced distribution of stress may result in greater thinning of plaque at the lateral portion. Therefore, the distortion of plaque may be a mechanism for atheroma rupture at the lateral portion.

Aged↗

[Successful treatment of diffuse aspiration bronchiolitis by cricopharyngeal myotomy].

A 62-year-old man was admitted to our hospital with complaints of coughing and fever. He had poliomyelitis at the age of 4 years, and had experienced difficulty in swallowing and chronic aspiration for the past 3 years. A chest roentgenogram and a high-resolution CT scan obtained on admission showed many small nodular shadows in the lower lung fields. Cricopharyngeal myotomy was done to decrease aspiration. The patient was then able to eat without aspiration, and the chest-roentgenographic and CT findings improved. Diffuse aspiration bronchiolitis was diagnosed from the clinical course and the radiographic findings. Cricopharyngeal myotomy can reduce the risk of aspiration in patients with diffuse aspiration bronchiolitis.

Bronchiolitis↗

[Dermatomyositis complicated by sarcoidosis].

We encountered a patient with dermatomyositis complicated by sarcoidosis. A 57-year-old woman was admitted to our hospital because of fever dry cough, and myalgias. There were reticular shadows on her chest X-ray film. Although the typical skin rash and myositis suggested the diagnosis of dermatomyositis biopsy specimens from a salivary gland, muscle, and lung revealed noncaseating granulomas as well. Uveitis was also noted. These findings suggested the coexistence of sarcoidosis with dermatomyositis. Examination of the lung-biopsy specimens showed interstitial pneumonia compatible with dermatomyositis, except for the granuloma. The typical rash of dermatomyositis and pathological findings of the lung specimen were inconsistent with sarcoidosis. Therefore we concluded that this patient had both dermatomyositis and sarcoidosis. This case sheds new light on the importance of pathological examinations.

Dermatomyositis↗

The possible role of bcl-2 expression in the progression of tumors of the uterine cervix.

BACKGROUND: A close link between human papillomavirus (HPV) and the development of uterine cervical neoplasias has been proposed. However, other cofactors also are required for malignant transformation. METHODS: Forty-six cervical intraepithelial neoplasias (CIN) I/II, 75 CIN III, and 60 invasive squamous cell carcinomas (ISCC) were investigated by immunohistochemical staining for bcl-2 protein (bcl-2), bax protein (Bax), estrogen receptor (ER), and progesterone receptor (PR). The presence of HPV-DNA was examined using the polymerase chain reaction assay. RESULTS: bcl-2 immunoreactivity was found in 17 of 46 (37%) CIN I/II, 48 of 75 (64%) CIN III, and 12 of 60 (20%) ISCC, the positivity in CIN III being significantly higher than in CIN I/II or ISCC (P < 0.004, P = 0.0001). The bcl-2 immunostaining pattern could be subdivided into two groups, basal type and diffuse type, with the incidence of the latter being clearly increased, in line with tumor progression. In the Bax or HPV-DNA positive groups, bcl-2 positive cases in CIN I/II were in the minority, whereas in CIN III they constituted the majority. In ISCC, bcl-2 positive was significantly lower than negative cases, not being associated with Bax and HPV-DNA. Estrogen receptor and PR immunoreactivity were rare. CONCLUSIONS: These results indicate that bcl-2 may play an important role in a relatively early stage of cervical tumorigenesis, in association with Bax expression and HPV infection.

Carcinoma, Squamous Cell↗

Postnatal development of periodontal ruffini endings in rat incisors: an immunoelectron microscopic study using protein gene product 9.5 (PGP 9.5) antibody.

Postnatal development of Ruffini endings was ultrastructurally investigated in the upper incisors of the rat from 1 day to 60 days after birth by means of protein gene product 9.5 (PGP 9.5) immunocytochemistry. The immunostaining with PGP 9.5 antibody clearly demonstrated chronological alterations of the distribution and ultrastructure of the Ruffini endings during postnatal development. At 1 day after birth, the PGP 9.5-positive nerve terminals contained a few mitochondria and vesicles immunonegative for PGP 9.5. Dendritic terminals appeared at 4 days after birth, with a small number of expanded or bulbous portions. These expanded portions possessed morphological features similar to those of the growth cone: several mitochondria and various kinds of vesicles. Typical Ruffini endings with dendritic ramification and expanded portions appeared 7-11 days after birth. At this stage, parts of the axon terminals extended through the slits of Schwann cell covering and formed finger-like projections called axonal spines. These Ruffini endings increased dramatically in number after 24-26 days and were identical in density and morphology to those seen in adult rats. After the commencement of the occlusion between the incisors, the number of large mitochondria increased, in contrast to the decrease of the vesicles in the axon terminals. Moreover, the axonal spines increased both in number and in length. Thus, the periodontal nerve endings showed stage-specific morphological features intimately related in timing to tooth eruption and occlusion. Functional stimuli possibly contribute to the final differentiation and maturation of the periodontal Ruffini endings.

Age Factors↗

Structural analysis of PKS1, a polyketide synthase gene involved in melanin biosynthesis in Colletotrichum lagenarium.

Albino mutants (Pks-) of Colletotrichum lagenarium form nonmelanized appressoria and possess little penetrating ability on the host plant. The defect in albino mutant 79215 (Pks-) is considered to lie in pentaketide biosynthesis and/or pentaketide cyclization during melanin biosynthesis. The cosmid pAC7, carrying the PKS1 gene, when transformed into the albino mutant restores the wild-type melanin phenotype. We have determine the DNA sequence and the transcriptional organization of the PKS1 gene. The PKS1 gene contains one open reading frame, consisting of 3 exons separated by two short introns. The predicted PKS1 polypeptide consists of 2187 amino acids and shows significant similarities with other polyketide synthases, particularly that encoded by wA in Aspergillus nidulans, involved in conidial pigmentation. The PKS1 gene contains highly conserved beta-ketoacyl synthase, acetyl/malonyl transferase, and acyl carrier protein domains. We propose that the C. lagenarium PKS1 gene encodes a polyketide synthase involved in melanin biosynthesis.

Amino Acid Sequence↗

Anaplastic large cell lymphomas expressing the novel chimeric protein p80NPM/ALK: a distinct clinicopathologic entity.

Anaplastic large cell lymphoma (ALCL) is a subtype of non-Hodgkin's lymphoma characterized by the CD30+ large neoplastic cells and sometimes carries a t(2;5)(p23;q35). Recently, we found a novel hyperphosphorylated 80-kD protein tyrosine kinase, p80, in ALCLs with t(2;5). Subsequent cDNA cloning showed p80 to be a fusion protein of two genes, the novel tyrosine kinase gene and the nucleophosmin gene, in accordance with the sequence of the NPM/ALK gene (Morris et al, Science 263:1281, 1994). Meanwhile, the clinicopathologic features of p80-carrying ALCLs have remained unclear. Paraffin sections of 105 cases of ALCL were immunostained using anti-p80 antibody, and 30 of them were shown to express p80. Clinicopathologic comparison between p80-positive and -negative ALCLs showed that p80-positive cases occurred in a far younger patient age group (16.2 +/- 12.9 years; p80-negative cases, 51.0 +/- 22.3 years; P < .0001) and the patients showed a far better 5-year survival rate (79.8%; p80-negative group, 32.9%; P < .01). These data showed that p80-positive ALCL is a distinct entity both clinically and pathogenetically and should be differentiated from p80-negative ALCL.

Adolescent↗

Aging changes mechanical loading thresholds for bone formation in rats.

The effect of aging on the mechanical loading thresholds for osteogenesis was investigated in rats. We applied mechanical loads varying from 30 to 64 N to the tibiae of 43 19-month-old rats using a four-point bending apparatus. Bone formation rates were measured on the periosteal and endocortical surfaces of the tibial midshaft using double-label histomorphometry. Bone formation rates from the old rats were compared with results from adult (9-month-old) rats that we reported earlier.(4) Bone formation on the periosteal surface of the old rats was predominantly woven-fibered. Periosteal bone formation was observed in a lower percentage of the old rats compared with the younger adult rats for applied loads of 40 N and greater (59% old, 100% adult). However, in the old rats that formed woven bone there were no significant differences in woven bone area (p=0.1) or surface (p=0.24) compared with younger adults. Therefore, the periosteum of old rats had a higher threshold for activation by mechanical loading, but after activation occurred, the cells had the same capacity to form woven bone as younger adult animals. On the endocortical surface, relative bone formation rates in old rats showed a marginal (p=0.06) increase in response to an applied load of 64 N but was not increased at lower loads. The relative bone formation rate in the old rats was over 16-fold less than that reported for the younger adult rats at an applied load of 64 N and the relative bone forming surface in old rats in this study was 5-fold less than it was younger rats under similar loading conditions. In the younger adult rats, a mechanical threshold for lamellar bone formation of 1050 microstrain was calculated for the endocortical bone surface. The old rats required over 1700 microstrain on the endocortical surface before bone formation was increased. The data suggest that both the periosteal and endocortical surfaces of the tibiae of older rats are less responsive to mechanical stimuli.

Adaptation, Physiological↗

Epstein-Barr virus association with early cancers found together with gastric medullary carcinomas demonstrating lymphoid infiltration.

Seven early gastric cancers obtained from patients also demonstrating Epstein-Barr virus (EBV)-positive gastric medullary carcinoma with lymphoid infiltration were investigated using a combined polymerase chain reaction (PCR) and in situ hybridization (ISH) approach. Sharing the same background mucosa as gastric medullary cancers, they comprised four intramucosal carcinomas, predominantly well-differentiated adenocarcinomas, and three submucosal carcinomas, histologically showing mixtures of well and poorly differentiated adenocarcinoma. In the three cases of submucosal carcinoma, the presence of EBV was proven by means of both PCR and ISH. However, not all cancer cells were positive for EBV on the basis of ISH examination, in contrast to the large series of gastric carcinoma with lymphoid infiltration previously investigated. All four mucosal carcinomas were EBV-negative. Lymphocyte-determined membrane antigen (LYDMA) monoclonality, performed by PCR, and latent membrane protein-1 (LMP-1) and Epstein-Barr virus (EBNA2) expression, assessed immunohistochemically, were negative in all seven cases. The results suggest that EBV becomes associated with gastric medullary carcinoma with lymphoid infiltration (GMCL) at a relatively early stage of the disease, shortly after the tumour has initially progressed to an invasive form, and plays some role in the manifestation as GMCL.

Adenocarcinoma↗

Bcl-2 expression and its association with cell kinetics in human gastric carcinomas and intestinal metaplasia.

The bcl-2 protooncogene was initially discovered at the t(14;18) chromosomal breakpoint in follicular lymphomas. It has been demonstrated that bcl-2 protein (Bcl-2) expression blocks apoptosis and plays an important role in cell development and maturation. In the present study, Bcl-2 expression was immunohistochemically examined in 103 cases of gastric carcinoma, as well as 64 cases of non-carcinous gastric mucosa, and its correlation with apoptosis, cell proliferation and p53 immunoreactivity was investigated. Bcl-2 was detected in 18.0% of differentiated-type gastric carcinomas (9 of 50) and 7.5% of the undifferentiated type (4 of 53). In adjacent intestinal metaplastic gastric epithelium, the incidence of Bcl-2 positivity in the incomplete type (21/23, 91.3%) was significantly higher than in the complete type (23/41, 56.1%) (P < 0.04). Double immunostaining for Bcl-2 and Ki-67 clearly revealed the majority of Bcl-2-positive cancer cells to be in a nonproliferating state, although some cancer cells expressed both proteins together. Statistical assessment demonstrated that the average Ki-67 labeling index and apoptotic labeling index in Bcl-2-positive foci were significantly lower than in Bcl-2-negative foci (P < 0.0001, P < 0.0003). In addition, a significant dissociation between Bcl-2 and p53 immunoreactivity was found in cancer tissues. These results indicate that aberrant Bcl-2 expression in gastric carcinomas possibly originates from intestinal metaplastic epithelium, and suggest a possible role in tumor development and growth.

Adenocarcinoma↗

Risedronate treatment does not increase microdamage in the canine femoral neck.

Cortical and trabecular bone from the femoral neck of 24 adult female beagle dogs was examined for microdamage following 2 years of treatment with risedronate (NE-58095). Specimens of the femoral neck, sectioned between the femoral head and the intertrochanteric groove, were bulk stained in 1% basic fuchsin in graded alcohols and embedded in methylmethacrylate. Five transverse sections of 100 microns from each specimen were examined for microdamage and measurement of cortical and trabecular area, and three sections from each specimen were measured for calculation of trabecular and cortical bone activation frequency (Ac.f) and bone formation rate (BFR/BV) in the superior and anterior regions of the femoral neck. Although no statistical differences were observed among groups for numerical density or length of microcracks, Kruskal-Wallis analysis showed differences among groups for both cortical and trabecular bone area (p < 0.05). Ac.f was significantly lower in both cortical bone (p < 0.05) and trabecular bone (p < 0.005) of the femoral neck at all dosage levels. No significant difference was observed among groups for trabecular mean wall thickness. The hypothesis that microdamage accumulation increases following reduction in Ac.f was not supported for the canine femoral neck in this experiment. This result could be explained by the fact that microdamage does not accumulate following treatment; that transient increases in microdamage at the beginning of the study period had been repaired; or finally, that the canine femoral neck does not reflect weight-bearing conditions of clinical relevance to humans for assessment of microdamage.

Animals↗

A histomorphometric study on effects of single and concurrent intermittent administration of human PTH (1-34) and bisphosphonate cimadronate on tibial metaphysis in ovariectomized rats.

This study compared the single administration of hPTH(1-34), bisphosphonate cimadronate (YM-175), and concurrent therapy of these two for restoration of lost bone mass in ovariectomized (OVX) rats. Animals were untreated for 4 weeks after surgery, and then injected s.c. with vehicle (OVX+V), hPTH(1-34) (30 micrograms/kg) (OVX+P), YM-175 (5 micrograms/kg) (OVX+Y), or a combination of these two (OVX+P+Y), 3 days a week, for 8 weeks, and sacrificed. Their proximal tibia were processed undecalcified for quantitative bone histomorphometry. Although OVX+Y showed a reduction of bone turnover compared to OVX+V, it failed to restore lost bone mass in OVX rats. In contrast, OVX+P exhibited a stimulation of bone formation and restored cancellous osteopenia due to OVX. OVX+P+Y also resulted a recovery of osteopenia, however, stimulation of bone formation by PTH was suppressed by YM-175.

Animals↗

Nucleolar organizer regions: a new prognostic factor for upper tract urothelial cancer.

PURPOSE: The prognostic significance of argyrophilic staining in the nucleolar organizer regions was studied in 63 patients with primary urothelial tumors of the renal pelvis and ureter. MATERIALS AND METHODS: Silver staining of paraffin embedded sections was performed using a 1-step technique. RESULTS: The prognosis for patients with a mean number of argyrophilic nucleolar organizer region proteins per nucleus (argyrophilic nucleolar organizer region score) of 8 or greater was significantly worse than that for patients with a score of less than 8 (P <0.001). CONCLUSIONS: Argyrophilic nucleolar organizer region score is a new prognostic factor in primary urothelial tumors of the renal pelvis and ureter, and it is particularly useful for patients with invasive tumors.

Adult↗

Apoptosis in gastric carcinomas and its association with cell proliferation and differentiation.

The significance of apoptosis in human gastric carcinomas was investigated in comparison with proliferative activity and p53 accumulation, using an in situ DNA nick end labeling method and immunohistochemistry for both Ki-67 antigen and p53 protein. Apoptotic labeling indices (LI) of 51 differentiated carcinomas (21 of early and 22 of advanced stage) were significantly lower than for 33 undifferentiated tumors (9 of early and 24 of advanced stage) (P < 0.05). In both types, apoptotic LI of advanced stage lesions were significantly higher than for the early stage cases (P < 0.005, P < 0.03). The distribution of apoptotic cells was different from that of Ki-67-positive cells, generally exhibiting an inverse correlation for areas of predominance. In contrast, there was no significant correlation between p53 immunoreactivity and either apoptotic LI or Ki-67 LI. It is concluded that in human gastric carcinomas the susceptibility to apoptosis is related to tumor cell differentiation and depth of invasion, and may play a role in selection of clonal subpopulations with high growth potential.

Antigens, Neoplasm↗