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T Otani

Publications and source records attributed to T Otani.

At least 19 recordsLinked to original sources
PubMed2004

Analysis of prognostic factors after surgery for stage III and IV gallbladder cancer.

AIM: Survival and prognostic factors were analysed in patients who had undergone surgical resection with curative intention with the aim of identifying groups of patient with stage III and IV gallbladder cancer on the TNM classification who might benefit from surgery. METHODS: Thirty-seven patients with advanced gallbladder cancer were studied, the cumulative survival rate for each group was calculated for each pTNM factor. RESULTS: The 5-year survival rates in the stage III patients were 83.3%, while those for the stage IVA patients were 46.2%, and those for the stage IVB patients 16.7%. CONCLUSIONS: In patients with invasion of adjacent organs, including the liver and gastrointestinal tract, and rated as pT3 or pT4, extended surgery excising the invaded tissue may be justified. In patients with pN2 lymph-node metastasis, even without adjacent organ invasion, radical surgery may not achieve a good outcome.

Aged↗
PubMed2004

Conservative treatment of isolated posterior cruciate ligament injury in professional baseball players: a report of two cases.

Conservative treatment is currently recommended for most isolated posterior cruciate ligament (PCL) injuries in athletes. However, it is not known whether conservative treatment is applicable even in high performance athletes with isolated PCL injury. The results in two extremely high performance athletes, professional baseball players with isolated acute PCL injury treated conservatively are reported. A catcher and an out fielder, who were regular players, hurt their knees in baseball games. Magnetic resonance images of the knee detected complete PCL rupture. Following a carefully guided physical therapy program, a 3-week period of immobilization of the knee in full extension was achieved with a knee brace, while performing hard quadriceps muscle strengthening exercise, and then running exercise was started. Six to eight weeks after injury, they were able to return fully to their original sporting activity despite tibial posterior translation on posterior drawer test, and to sustain this activity over 2 years. Switching of weight-bearing to non-weight-bearing in a deep knee flexion is considered to contribute to subjective instability in athletes with PCL-deficiency. Probably because our cases, even though extremely high performance athletes were infrequently subjected to such a situation while playing baseball, they were able to return to their pre-injury level of athletic performance without severe subjective instability through conservative treatment.

Adult↗
PubMed2003

Gliomatosis cerebri evaluated by 18Falpha-methyl tyrosine positron-emission tomography.

Gliomatosis cerebri is a rare condition in which an infiltrative glial neoplasm spreads through the brain with preservation of the underlying structure. CT and MRI show diffuse abnormal density or signal, without mass effect, and because these findings are nonspecific, it is difficult to make a definitive diagnosis. Our purpose was to assess the usefulness of a new tumour-detecting amino acid tracer for positron-emission tomography (PET), L-[3-(18)F] alpha-methyl tyrosine (FMT), in patients with gliomatosis cerebri. We performed FMT PET, fluorodeoxyglucose FDG PET and MRI eight patients with gliomatosis cerebri and six with non-neoplastic disease, whose MRI also showed diffuse high signal on T2-weighted images. Standardised uptake (SUV) of FMT and FDG in the area of gliomatosis was obtained and the tumour-to-normal cortex (T/N) ratio of this was compared. The tumours were shown on FMT PET as areas of increased uptake, except in one patient with severe intracranial hypertension. There were significant differences between the SUV of FMT and the T/N ratio of FMT in patients and in controls (both P<0.01), and between the T/N ratio of FMT and FDG in patients ( P<0.01). Increased uptake of FMT PET strongly suggests neoplasia. FMT PET is valuable for differentiating gliomatosis cerebri from non-neoplastic diseases showing similar diffuse high signal on T2-weighted images and little contrast enhancement.

Adult↗
PubMed2003

Smallest Todani's type II choledochal cyst.

A choledochal cyst is defined as an isolated or combined congenital dilation of the extra hepatic or intrahepatic biliary tree. Todani and colleagues proposed the five types of congenital choledochal cysts which have gained widespread acceptance. Type II choledochal cyst, a diverticulum of common bile duct, is rarest, and most reported cases of Type II were as large as several centimeters in size. We herein report the case of a small Type II choledochal cyst which was resected at pancreatoduodenectomy for carcinoma of the papilla of Vater. A 58-year-old Japanese male was referred to our hospital for the evaluation of jaundice. Preoperative cholangiogram via the percutaneous transhepatic biliary drainage tube revealed a complete obstruction at the narrow terminal segment. Furthermore, a small diverticular protrusion was demonstrated on the lower part of the common bile duct. The resected specimen showed a 2.2 x 1.7 x 1.2 cm carcinoma of the major papilla, and a deep, 2 mm in diameter and 5 mm in depth, depression on the posterior wall of the common bile duct. The anomalous pancreatobiliary duct was not seen. The deep depression was confirmed microscopically to penetrate the fibromuscular layer of the common bile duct and diagnosed as a Todani's Type II choledochal cyst. To our knowledge, the current case is the smallest Type II choledochal cyst which was completely resected.

Cholangiography↗
PubMed2003

Simultaneous immunohistochemical localization of beta-catenin and cyclin D1 in differentiated but not in undifferentiated human endometrial carcinoma.

PURPOSE: Beta-catenin plays dual important roles in epithelial cell-cell adhesion in cytoplasm as well as in the nuclear T-cell factor (TCF)/lymphoid enhancing factor-1 (LEF-1) signaling pathway. Abnormal nuclear accumulation of beta-catenin promotes colorectal carcinogenesis by triggering the expression of cyclin D1 gene through the TCF/LEF-1 pathway. The purpose of this study was to investigate the possible involvement of the TCF/LEF-1 pathway in endometrial carcinogenesis. METHODS: Immunohistochemical localization of beta-catenin and cyclin D1 in normal endometrium, hyperplastic endometrium and endometrial carcinoma were assessed on serial tissue sections. RESULTS: Nuclear accumulation of beta-catenin was observed in endometrial carcinomas compared with normal endometria. Cyclin D1-positive endometrial cancer cases were beta-catenin-positive in the nuclei, especially in 70% (7/10) of G1 and 55.6% (5/9) of G2 differentiated endometrial carcinomas, but never in G3 undifferentiated ones. CONCLUSIONS: These results imply that the simultaneous nuclear accumulation of beta-catenin and cyclin D1--suggesting the activation of the TCF/LEF-1 pathway--may be a potential marker for the progression of Type 1 endometrial carcinogenesis.

Adult↗
PubMed2002

Caffeine test in predicting flutamide-induced hepatic injury in patients with prostate cancer.

The caffeine test measures the activity of cytochrome p450 (CYP1A2) which is a major enzyme involved in the activation of flutamide. The usefulness of this test in predicting flutamide-induced hepatic injury in patients with prostate cancer was examined. The subjects were: (1). five patients whose aspartate aminotransferase (AST) or alanine aminotransferase (ALT) level rose to 100 IU/l or higher following the start of flutamide (moderately injured group); (2). four patients whose AST and ALT levels were higher than normal but less than 100 IU/l (mildly injured group); and (3). two patients whose hepatic function remained normal (normal group). The subjects were each given canned coffee to drink. Urinary caffeine (137X), paraxanthine (17X) and 1, 7-dimethyluric acid (17U) levels were measured 4-5 h later. The metabolite ratio, (17U+17X)/137X, was calculated to serve as an indicator of CYP1A2 activity. The metabolite ratio for the moderately injured group (3.98+/-1.56) and the mildly injured group (5.55+/-1.42) were lower than that for the normal group (9.56). The results suggest that a decrease in CYP1A2 activity is involved in the onset of flutamide-induced hepatic injury, and that the caffeine test seems to provide a useful means of its prediction.

Aged↗
PubMed2001

Solution structures of C-1027 apoprotein and its complex with the aromatized chromophore.

C-1027 is one of the most potent antitumor antibiotic chromoproteins, and is a 1:1 complex of an enediyne chromophore having DNA-cleaving ability and a carrier apoprotein. The three-dimensional solution structures of the 110 residue (10.5 kDa) C-1027 apoprotein and its complex with the aromatized chromophore have been determined separately by homonuclear two-dimensional nuclear magnetic resonance methods. The apoprotein is mainly composed of three antiparallel beta-sheets: four-stranded beta-sheet (43-45, 52-54; 30-38; 92-94; 104-106), three-stranded beta-sheet (4-6; 17-22; 61-66), and two-stranded beta-sheet (70-72; 83-85). The overall structure of the apoprotein is very similar to those of other chromoprotein apoproteins, such as neocarzinostatin and kedarcidin. A hydrophobic pocket with approximate dimensions of 14 A x 12 A x 8 A is formed by the four-stranded beta-sheet and the three loops (39-42; 75-79; 97-100). The holoprotein (complex form with the aromatized chromophore) structure reveals that the aromatized chromophore is bound to the hydrophobic pocket found in the apoprotein. The benzodihydropentalene core of the chromophore is located in the center of the pocket and other substituents (beta-tyrosine, benzoxazine, and aminosugar moieties) are arranged around the core. Major binding interactions between the apoprotein and the chromophore are likely the hydrophobic contacts between the core of the chromophore and the hydrophobic side-chains of the pocket-forming residues, which is supplemented by salt bridges and/or hydrogen bonds. Based on the holoprotein structure, we propose possible mechanisms for the stabilization and the release of chromophore by the apoprotein.

Actinomycetales↗
PubMed2001

Apoptosis and the expression of Bcl-2 and Bax in patients with endometrioid, clear cell, and serous carcinomas of the uterine endometrium.

OBJECTIVES: Clear cell and serous carcinoma of the uterus are rare types of endometrial carcinomas. This study was designed to investigate the differential occurrence of apoptosis, Bcl-2, and Bax in endometrioid, clear cell, and serous carcinomas. METHODS: In a total of 28 endometrial carcinomas as well as 4 samples of normal postmenopausal endometria, apoptotic changes were examined using molecular biochemical techniques. The expression of Bcl-2 and Bax proteins was also investigated by immunohistochemical staining with appropriate antibodies. RESULTS: Labeling of DNA in situ indicated that apoptotic cells were sporadically seen in postmenopausal endometrium (5.2 +/- 2.1, n = 4). In contrast, cells undergoing apoptosis apparently were detected in endometrioid carcinoma (29.3 +/- 3.7, n = 20), and their numbers increased intensely in clear cell (49.5 +/- 5.6, n = 5) and serous carcinomas (50.8 +/- 6.0, n = 3). Autoradiographic analysis revealed that high-molecular-weight DNA was predominant in postmenopausal endometrium. However, a DNA ladder was identified in 7 of 10 carcinomas. Although Bcl-2 was immunonegative or faintly immunopositive in all cases, many cases of endometrioid carcinoma (43.6 +/- 4.1%, n = 20) were immunopositive for Bax, unlike postmenopausal endometrium (17.6 +/- 6.7%, n = 4). Moreover, the number of cells expressing Bax increased in clear cell (60.4 +/- 6.5%, n = 5) and serous carcinomas (66.8 +/- 7.6%, n = 3) compared with that in endometrioid carcinoma. CONCLUSIONS: These results indicate that apoptosis occurs in a specific population of cells in different histologic components of endometrial carcinomas. The expression of Bax, but not of Bcl-2, might suggest histologic differentiation in endometrial carcinomas.

Adenocarcinoma↗
PubMed2001

Production of activin A in hyperplasia and adenocarcinoma of the human endometrium.

OBJECTIVES: To examine the possible localization and production of activin A in human normal endometrium, endometrial hyperplasia, and adenocarcinoma tissues. METHODS: Human endometrial tissues were collected from 45 patients who were undergoing abdominal hysterectomy. Tissue sections were stained with monoclonal antibodies against the inhibin/activin alpha- and beta A-subunits and activin A using an avidin-biotin-peroxidase complex technique. Concentrations of activin A and inhibin A in tissue extracts of the endometrial tissues were measured using enzyme-linked immunosorbent assays (ELISAs). The expressions of the inhibin alpha-subunit and activin beta A-subunit messenger RNA (mRNA) in the endometrial tissues were demonstrated by reverse transcription-polymerase chain reaction (RT-PCR) analysis. RESULTS: No immunostaining with an antibody against the inhibin alpha-subunit was observed in human normal endometrium, endometrial hyperplasia, and adenocarcinoma. By contrast, immunostaining for the activin beta A-subunit and activin A was observed in the cytoplasm of glandular cells in normal endometrium, endometrial hyperplasia, and tumor cells of endometrial adenocarcinoma. The percentages of stained cells in endometrial adenocarcinoma were higher than those in normal endometrium. Also, the percentages of stained tumor cells with poor differentiation were higher than those with good and moderate differentiation of the endometrium. The stromal cells in normal endometrium, endometrial hyperplasia, and adenocarcinoma were weakly immunoreactive with antibodies against the beta A-subunit and activin A. Immunoreactivity of activin A in tissue extracts from normal endometrium and endometrial adenocarcinoma was detected by the two-site ELISA. Immunoreactivity of activin A was significantly higher in adenocarcinoma than in normal endometrium. On the other hand, the immunoreactive inhibin A was not detected. The expression of the alpha-subunit mRNA in endometrial tissues was demonstrated as the RT-PCR products migrated at 905 bp and the PCR products of the beta A-subunit showed a band at 366 bp. CONCLUSIONS: It is suggested that activin A, but not inhibins, are produced by endometrial tissues. The amounts of produced activin A were higher in adenocarcinoma tissues than in normal endometrium. Activin A might be involved in human endometrial tumorigenesis.

Activins↗
PubMed2001

Involvement of conserved hydrophobic residues in the CTLD of human lectin-like oxidized LDL receptor in ligand binding.

We previously identified the hydrophilic residues that are essential for ligand binding in the C-type lectin-like domain (CTLD) of human lectin-like oxidized LDL receptor (hLOX-1). To provide a more detailed understanding of ligand binding, we selected in the present study 13 conserved hydrophobic residues in the CTLD of hLOX-1 for mutagenesis analysis. The selected residues were replaced either by Ser (drastic mutation) or by size- and structure-based alternative hydrophobic residues (conserved mutation). Mutation targeted at F228, Y238, and G232 deprived hLOX-1 of ligand binding without alteration of protein expression and localization. In contrast, drastic mutation introduced into positions W203, W215, and W217 resulted in mislocalization, whereas conserved mutation at the same sites resulted in clones with similar cell surface localization and ligand binding to native hLOX-1. Our results indicate that F228, Y238, and G232 are essential for ligand binding, while W203, W215, W217, and L206 play a structural role.

Amino Acid Sequence↗
PubMed2001

Roles of the anterior cruciate ligament and the medial collateral ligament in preventing valgus instability.

Both the medial collateral ligament (MCL) and the anterior cruciate ligament (ACL) are reported to prevent valgus instability of the knee. In this study, the anatomical mechanisms by which these ligaments prevent valgus instability were experimentally investigated. The valgus rotation angle and the magnitude of the medial joint space opening were measured in six cadaveric knees, using biplanar photography before and after the MCL and/or the ACL were severed. A significant increase in the valgus rotation angle and a large medial joint space opening were observed when the MCL was severed. An increase in the valgus rotation angle was also observed when the ACL was severed, but only a small medial joint space opening was present. The increase in the valgus rotation angle after ACL severance was nearly parallel to the increase in the internal rotation of the tibia. Thus, we concluded that both ligaments function to prevent valgus instability, but that the anatomical reasons for their function are different. The MCL prevents valgus instability by stopping an opening in the medial joint space. The ACL, on the other hand, prevents the internal rotation of the tibia. When the ACL is severed, the internal rotation increases, and causes the valgus rotation angle to also increase, despite the presence of only a small medial joint space opening.

Adult↗
PubMed2001

Implications of adrenomedullin expression in the invasion of squamous cell carcinoma of the uterine cervix.

BACKGROUND: Adrenomedullin (AM) is a multifunctional peptide involved in a variety of physiological functions, including vasodilatation, growth regulation, and carcinogenesis. To elucidate the possible role of AM in the growth and invasion of uterine cervical carcinoma, the presence and distribution of AM and AM mRNA was examined in the neoplastic changes of squamous epithelium of the uterine cervix. METHODS: The expression of AM mRNA by CaSki, a uterine squamous cell carcinoma cell line, was examined by reverse transcriptase-polymerase chain reaction (RT-PCR). The presence and distribution of AM and AM mRNA in sections of normal cervical tissues, cervical intraepithelial neoplasia (CIN), and invasive squamous cell carcinomas were evaluated by immunohistochemical staining with a specific antibody against AM and by in situ RT-PCR, respectively. RESULTS: AM mRNA expression in CaSki cells was demonstrated by RT-PCR. Immunohistochemical staining for AM and in situ RT-PCR revealed that AM and AM mRNA were expressed in invasive squamous carcinoma cells, but not in normal cervical epithelium or in CIN lesions. Abundant expression of AM and AM mRNA was localized in the cytoplasm of carcinoma cells of bulky invasive carcinomas, while in early invasive carcinoma, the expression of AM and AM mRNA was more prominent in stromal cells adjacent to the early invasive carcinoma cells than in the carcinoma cells themselves. CONCLUSIONS: Because AM expression was evident only in invasive cervical squamous carcinoma cells and the stromal cells adjacent to early invasive carcinomas, it is likely that AM may play an important role in the growth and invasion of squamous cell carcinoma of the uterine cervix.

Adrenomedullin↗
PubMed2001

Tomographic findings of foveal hard exudates in diabetic macular edema.

PURPOSE: To report the intraretinal location of foveal hard exudates after vitrectomy to treat diabetic macular edema and to evaluate the visual outcome. METHODS: In a prospective study, the tomographic features of 11 eyes (8 patients) with diabetic macular edema were evaluated with optical coherence tomography after vitrectomy. The intraretinal location of hard exudates at the fovea (anatomic foveola) and the relationship with visual acuity were investigated. RESULTS: With optical coherence tomography, hard exudates were observed as highly reflective spots in the cross-sectional images. In six of 11 eyes (54.5%), the hard exudates were in the inner portion of the neurosensory retina; the final best-corrected visual acuity averaged 20/70 in the six eyes. In the remaining five eyes (45.5%), hard exudates were deposited not only in the neurosensory retina but also in the subretinal space. In optical coherence tomographic images, subretinal hard exudates were observed as highly reflective plaques, which were slightly elevated over the retinal pigment epithelium. The five eyes developed a serous retinal detachment at the fovea before or after vitrectomy. Subretinal hard exudates bridged the detached neurosensory retina and the retinal pigment epithelium in two eyes. The average final visual acuity level in the five eyes was 20/300. The visual outcome was significantly worse in five eyes with subretinal hard exudates than in six eyes with an intraretinal one (P <.05, Wilcoxon rank sum tests). CONCLUSIONS: If serous retinal detachment develops before or after vitrectomy for diabetic macular edema, hard exudates tend to accumulate not only in the neurosensory retina but also in the subretinal space. The visual prognosis is worse in cases of subretinal exudation.

Aged↗
PubMed2001

Proper use of MR imaging in internal derangement of the knee (orthopedic surgeon's view).

MR imaging of the knee is a highly accurate examination in terms of the detection of meniscal tears and cruciate ligament ruptures among internal derangement of the knee. The overall accuracy in more than 2000 published cases reached nearly as high as 90% in meniscal tears, and 94% in anterior cruciate ligament (ACL) and 99% in posterior cruciate ligament (PCL) ruptures. Furthermore, the negative predictive value of the knee MR imaging, the number of true negative examination results divided by the numbers of true negative plus false-negative examination results, reaches almost 100% because of its very low false-negative rate. Therefore, from the orthopedic surgeon's point of view, even though the medical cost becomes a great concern, MR imaging has prime importance in the diagnosis of the internal derangement of the knee.

Anterior Cruciate Ligament Injuries↗
PubMed2001

Apoptosis and the expression of Bax and Bcl-2 in hyperplasia and adenocarcinoma of the uterine endometrium.

BACKGROUND: Apoptosis plays a crucial role in carcinogenesis in various tumours. This study was designed to investigate the occurrence of apoptosis and the expression of Bcl-2 and Bax proteins in endometrial tumours of corpus uteri. METHODS: Endometrial tissues were obtained from 20 patients with endometrioid adenocarcinoma, 16 patients with endometrial hyperplasia, and 4 patients with myoma uteri (which were used as controls). The occurrence of apoptosis was examined by using molecular biochemical techniques. The expression of Bcl-2 and Bax proteins was also investigated using immunohistochemical staining with appropriate antibodies. RESULTS: The labelling of DNA in situ indicated that apoptotic cells were sporadically seen in postmenopausal endometrium (5.2 +/- 2.1, n = 4) and endometrial hyperplasia without atypia (2.6 +/- 0.5, n = 9). In contrast, labelled cells were detected in atypical endometrial hyperplasia (15.9 +/- 2.2, n = 7), and their numbers increased intensely in adenocarcinoma (29.3 +/- 3.7, n = 20). Autoradiographic analysis revealed DNA laddering in many cases of carcinoma. Bcl-2 was highly immunopositive in hyperplasia without atypia (36.2 +/- 6.5%, n = 9), but was decreased in the atypical endometrial hyperplasia (16.3 +/- 4.8%, n = 7). Large fractions of the carcinoma (6.3 +/- 1.8%, n = 20) and normal endometrium (2.8 +/- 1.4%, n = 4) were immunonegative or slightly immunopositive to Bcl-2. In contrast, Bax immunoreactivity was more frequent and stronger in adenocarcinoma (43.6 +/- 4.1%, n = 20) than that in normal endometrium (17.6 +/- 6.7%, n = 4) and hyperplasia (7.2 +/- 2.2%, n = 16). CONCLUSIONS: These results suggest that cells in hyperplasia expressing Bcl-2 might have prolonged survival ability. Neoplastic cells in adenocarcinoma might show apoptosis in association with a decreased expression of Bcl-2 and an increased expression of Bax. Therefore, the frequency of apoptosis and the expression of Bcl-2 and Bax might be correlated with carcinogenesis in the uterine endometrium of humans.

Adenocarcinoma↗