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T Ozaki

Publications and source records attributed to T Ozaki.

At least 19 recordsLinked to original sources
PubMed2004

Reduced inflammatory pain in mice deficient in the differential screening-selected gene aberrative in neuroblastoma.

Differential screening-selected gene aberrative in neuroblastoma (Dan) protein is produced in small neurons of dorsal root ganglia. Thermal and mechanical allodynia and Fos expression in the spinal dorsal horn evoked by inflammation and neuropathic pain were investigated using Dan-deficient mice. Mice showed pain reactions induced by the introduction of complete Freund's adjuvant (CFA) into their hind paw (inflammatory pain model) and after sciatic nerve ligation (neuropathic pain model). In the inflammatory pain model, thermal and mechanical pain thresholds in Dan-deficient mice were significantly higher than those of wild-type mice. The number of Fos-immunoreactive cells in the dorsal horn during the inflammatory period was significantly less in Dan-deficient mice. However, in the neuropathic pain model, no differences in thermal hypersensitivity, mechanical allodynia, or the number of Fos-immunoreactive cells in the dorsal horn were observed between the mice. These data suggest that Dan may be a neuromodulator in inflammatory pain.

Animals↗
PubMed2003

Tumors of the pelvis: complications after reconstruction.

INTRODUCTION: Complications after pelvic sarcoma surgery are frequent; however, the reports on complications are limited. Results of the authors' experience with 110 primary pelvic tumor resections and methods to achieve low complication rates for pelvic reconstruction are reported. MATERIALS AND METHODS: From 1982 to 1996, 110 patients with pelvic sarcoma (42 Ewing sarcomas, 40 chondrosarcomas, 21 osteosarcomas, and 7 other malignant tumors) underwent surgery. Sixteen patients underwent implantation of a hemipelvic megaprosthesis, 13 patients had implantation of an allograft for sacroiliac arthrodesis, 12 patients had implantation of an autograft for sacroiliac arthrodesis, and 17 patients underwent hip transposition. There were 9 hindquarter amputations, 6 implantations of allograft and total hip endoprosthesis, 1 implantation of prosthesis with autograft, and 1 implantation of allograft and autograft. No skeletal reconstruction was done in 35 patients. RESULTS: Postoperative function was as follows: 37% in patients with prosthesis, 60% in allograft, 66% in autograft, 66% in hip transposition, 37% in amputation, and 79% without reconstruction. In total, 10/16 patients with prosthetic replacement, 9/13 with allograft implantation, 4/12 with autograft implantation, 7/17 with hip transposition, 5/9 with amputation, 6/6 with prosthesis and allograft, and 12/35 without skeletal reconstruction had complications. Frequent complications depending on the reconstruction were infection in 6/10 prostheses and in 5/13 allografts, leg length discrepancy in 2/12 autografts and 4/17 hip transpositions, hematoma in 3/9 amputations, and infection (6) and skin problems (5) in 6 prostheses with allograft. CONCLUSION: Because of the small number of complications and good function, autograft implantation after iliac resection and hip transposition after acetabular resection are advisable.

Acetabulum↗
PubMed2003

Sawtooth oscillation in current-carrying plasma in the large helical device.

Sawtooth oscillations have been observed in current-carrying helical plasmas by using electron-cyclotron-emission diagnostics in the Large Helical Device. The plasma current, which is driven by neutral beam injection, reduces the beta threshold of the sawtooth oscillation. When the central q value is increased due to the plasma current, the core region crashes, and, when it is decreased, the edge region crashes annularly. Observed rapid mixture of the plasma in the limited region suggests that these sawtooth crashes are reconnection phenomena. Unlike previous experiments, no precursor oscillation has been observed.

Journal Article↗
PubMed2003

Evaluation of mutans streptococci in plaque and saliva: correlation with caries development in preschool children.

OBJECTIVES: To test the ability of a site-specific method of evaluating mutans streptococci (MS) present in plaque in order to predict caries risk in children and to compare the results with those obtained from estimating the levels of MS present in saliva. METHODS: Caries prevalence was examined twice, 6 months apart, in 129 preschool children ranging in age from 1.5 to 5. A commercial strip method was used to evaluate the MS score (0-3) in plaque collected from four selected tooth surfaces at two interdental spaces and in saliva. RESULTS: The screening criteria of the MS score for caries incidence between scores 1 and 2, and scores 0 and 1 were the most valid for evaluating plaque (accuracy of prediction, 80%) and saliva (accuracy of prediction, 71%), respectively. Based on these screening criteria, the evaluation of saliva MS was invalid when the plaque MS score was considered. Screening plaque MS was effective, regardless of caries experience at baseline, according to the chi-square test (p<0.01), but screening saliva MS was ineffective when caries experience was present at baseline. A multivariate logistic regression analysis including six variables showed that the plaque MS score and caries experience at baseline were significantly correlated with caries incidence: caries experience at baseline (OR=5.02, 95%CI: 1.81-14.59) and high plaque MS score (2 or 3) (OR=12.59, 95%CI: 3.18-67.08). CONCLUSIONS: These results suggest that the semi-quantitative evaluation of plaque MS sampled from only two proximal sites on the molars is more effective for screening preschool children at a high risk of developing caries in their primary dentition than other important caries risk indicators.

Chi-Square Distribution↗
PubMed2002

Empirical method for prediction of the coordination environment of Eu(III) by time-resolved laser-induced fluorescence spectroscopy.

The number of water molecules in the inner-sphere (N(H2O)) was determined for Eu(III) and the strength of ligand field (R(E/M)) was evaluated for a variety of coordination environments from the luminescence lifetime and the relative intensity at 615 nm and at 592 nm, by time-resolved laser-induced fluorescence spectroscopy. When R(E/M) and deltaN(H2O) for Eu(III) with a known coordination environment were plotted clear regularity was apparent between the location of the R(E/M)-deltaN(H2O) plot and the coordination environment of Eu(III). Here, deltaN(H2O) was calculated by use of the equation, deltaN(H2O)=9-N(H2O). Unknown coordination environments of Eu(III) can, in turn, be characterized, including both the inner- and the outer-sphere, simply by plotting R(E/M) and deltaN(H2O) for Eu(III) on the diagram. This empirical method is effective for prediction of the coordination environment of hydrated and complexed Eu(III) in solutions and that of the adsorbed Eu(III) on ion-exchange resins and by microorganisms.

Journal Article↗
PubMed2002

Measurements of blue shifts due to collisionless absorption in harmonic generation from subpicosecond laser-produced plasmas.

Harmonic generation from solid surface plasmas is studied using a subpicosecond Nd:glass laser system. For a 45 degrees angle of incidence, the speculars up to the fifth harmonics are blue shifted when the laser intensity exceeds 2 x 10(16) W cm(-2). The second harmonic is blueshifted by approximately 16 A, and the fifth harmonic is blue shifted by approximately 51 A for p polarization at the intensity of 1 x 10(17) W cm(-2). We observed the blue shift of the fifth harmonics and found that the magnitude of blue shift is higher compared with that for the second harmonics. The blue shift is interpreted as a collisionless absorption due to the anomalous skin effect. It is also found that the divergence of harmonics preserves a smaller divergence when using a shorter pulse length for the driving laser.

Journal Article↗
PubMed2002

Island dynamics in the large-helical-device plasmas.

In the Large Helical Device plasma discharges, the size of an externally imposed island with mode number ( n/m = 1/1) decreases substantially when the plasma is collisionless ( nu(*)< approximately 1) and the beta is finite ( > approximately 0.1%) at the island location. For the collisional plasmas with finite beta, on the other hand, the size of the island increases. However, there is a threshold in terms of the vacuum island size below which the island enlargement is not seen.

Journal Article↗
PubMed2002

Revision hip arthroplasty in a patient with a hip rotationplasty (type B III b).

We report for the first time a patient who underwent a revision hip arthroplasty after a hip rotationplasty (Winkelmann type B III b) because of a chondrosarcoma in 1988. The clinical symptoms and radiographic findings (X-ray, bone scintigraphy, arthrography) of the aseptic loosening of the acetabular component are presented in detail. Furthermore, we present the functional results after hip revision.

Adult↗
PubMed2002

Evaluation of acrosome reaction and viability of human sperm with two fluorescent dyes.

OBJECTIVE: To evaluate the usefulness of the Hoechst 33258/FITC-Pisum sativum agglutinin (FITC-PSA) staining for simultaneous assessment of viability and acrosome reaction rate (%AR) of human sperm. MATERIAL AND METHODS: Fresh sperm was collected 13 fertile donors provided fresh semen. We used motile sperm selected by the "swim-up" procedure using modified HTF. Hoechst 33258 was added and co-incubated with sperm for 10 min. Samples were washed free of unbound stain and the sperm were mounted as smears on glass slides. After drying, sperms were incubated with FITC-PSA for 30 min. Sperm were examined by fluorescence microscopy. Also, FITC-Concanavalin A (FITC-ConA) staining and vital staining with yellowish eosin were performed simultaneously. The correlation of viability and %AR were analyzed. RESULTS: Four different staining patterns were observed and clearly distinguished as follows: a) Viable acrosome-reacted sperm, b) Viable acrosome-intact sperm, c) dead acrosome-reacted sperm, d) dead acrosome-intact sperm. There was significant correlation between the results obtained by Hoechst 33258 and vital staining methods in viability of human sperm (r = 0.927, P < 0.001). There was significant correlation between the two methods (FITC-PSA and FITC-ConA) in %AR of human sperm (r = 0.92, P < 0.001). CONCLUSION: Viability and acrosome status of a human sperm can be easily assessed simultaneously by Hoechst 33258/FITC-PSA staining method. This combination method is considered useful to evaluate sperm function.

Acrosome Reaction↗
PubMed2002

Differential screening-selected gene aberrative in neuroblastoma protein modulates inflammatory pain in the spinal dorsal horn.

Differential screening-selected gene aberrative in neuroblastoma (DAN) belongs to a novel gene family that includes the Xenopus head-inducing factor, Cerberus and the dorsalizing factor, Gremlin. It has been suggested that members of this family control diverse processes in growth, development and the cell cycle.Here, we demonstrate that the DAN protein is produced in the small neurons of the dorsal root ganglion and is transported to the nerve terminals in the spinal dorsal horn in adult rats. Furthermore, intrathecal injection of an antibody to the DAN protein suppressed inflammatory pain caused by the introduction of complete Freund's adjuvant or carrageenan into the rat hindpaw. The amount of mRNA for DAN in dorsal root ganglion neurons and of its expressed protein in the spinal dorsal horn were both increased in inflammatory models.Together, these data suggest that the DAN protein may be a novel neuromodulator in primary nociceptive nerve fibers.

Afferent Pathways↗
PubMed2002

Utility of color Doppler indices of dominant follicular blood flow for prediction of clinical factors in in vitro fertilization-embryo transfer cycles.

OBJECTIVE: To investigate the relationship between color Doppler indices of dominant follicular blood flow and clinical factors in in vitro fertilization-embryo transfer cycles. SUBJECTS AND METHODS: This was a prospective study involving 26 patients completing a total of 33 in vitro fertilization cycles. Dominant follicular blood flow indices, peak systolic velocities, the resistance index and the pulsatility index were evaluated using transvaginal color Doppler. The indices were compared to the clinical outcomes of in vitro fertilization-embryo transfer. RESULTS: There was a significant correlation between dominant follicular peak systolic velocities and the number of oocytes retrieved, as well as the number of mature oocytes obtained. There was no significant correlation between dominant follicular resistance index or pulsatility index and the number of follicles > 10 mm in diameter, the number of oocytes retrieved or the number of mature oocytes. There were no significant differences between dominant follicular peak systolic velocities, resistance index or pulsatility index, and fertilization rate or the ratio of good quality embryos. However, significant differences were found between the number of oocytes retrieved, as well as the number of mature oocytes for those patients in which the peak systolic velocity was below 25 cm/s. CONCLUSIONS: Doppler assessment of dominant follicle blood flow alone is useful for predicting the number of retrievable oocytes. However, morphological quality of the embryo produced or the pregnancy rate cannot be predicted by this method.

Adult↗
PubMed2002

Population-based genetic alterations in Ewing's tumors from Japanese and European Caucasian patients.

BACKGROUND: The incidence of Ewing's tumors (ETs) is lower in Asians or African-Americans than in Caucasians. PATIENTS AND METHODS: Japanese ETs were available for analysis of chromosomal aberrations by comparative genomic hybridization (n = 16) and for expression of chimeric EWS transcripts by reverse-transcriptase polymerase chain reaction (n = 11). These results in Japanese patients were compared with those of 62 ETs in European Caucasian patients registered in the European Intergroup Cooperative Ewing's Sarcoma Study. RESULTS: Japanese patients with ET had lower overall survival (P = 0.0446) and relapse-free survival (P = 0.0371) compared with European Caucasian patients. Ten of 11 Japanese ETs and 31 of 62 European Caucasian ETs had type I (EWS exon 7 to FLI1 exon 6) fusion transcripts. In Japanese ETs, the median numbers of chromosomal aberrations were 2.0 and 6.0 in 11 primary tumors and five relapsed tumors, respectively. In European Caucasian ETs, the median number of changes were 2.5 and 5.0 in 52 primary and 10 relapsed tumors, respectively. Frequent gains were 8q (38%), 8p (31%) and 12q (25%) in Japanese ETs and 8q (52%), 8p (48%) and 12q (19%) in European Caucasian ETs. Frequent losses were 19q (44%), 19p (38%) and 17p (25%) in Japanese ETs and 16q (21%), 19q (18%) and 17p (15%) in European Caucasian ETs. The incidence of losses of 19p (P = 0.0215) and 19q (P = 0.0277) were significantly higher in Japanese ETs than in European Caucasian ETs. An amplification (1p33-p34) was observed in only one Japanese ET. CONCLUSIONS: Japanese patients with ET in this study had a worse prognosis than European Caucasian patients. In molecular genetic analyses, Japanese ETs had a higher frequency of loss of chromosome 19 than European Caucasian ETs. Different genetic aberrations may explain the different incidences and prognoses of ET between Caucasian and Japanese patients.

Adolescent↗
PubMed2002

Reconstruction of the proximal humerus after wide resection of tumours.

In 45 patients we assessed the functional results and complications for three different reconstructive procedures after resection of primary tumours of the proximal humerus. An osteoarticular allograft was used in 11, a clavicula pro humero operation in 15 and a tumour prosthesis in 19. The glenoid was resected with the proximal humerus in 25 patients. The axillary nerve was resected in 42 patients. The complication rate was lowest after reconstruction with a tumour prosthesis. The clavicula pro humero operation resulted in the most revisions. Cumulative survival rates for all the reconstructive procedures were similar. At follow-up at two years the functional results for the three reconstructive procedures were the same with a mean functional rating of 79% (Musculoskeletal Tumor Society). Excision of the glenoid had no influence on the functional result. Our findings indicate that the use of a tumour prosthesis is the most reliable limb-salvage procedure for the proximal humerus. The clavicula pro humero is an appropriate procedure if a prosthesis cannot be used.

Adult↗
PubMed2002

Sweet's syndrome associated with pigmented villonodular synovitis.

Sweet's syndrome (acute febrile neutrophilic dermatosis) was first described in 1964. The typical symptoms of Sweet's syndrome are high temperature, peripheral leucocytosis, painful cutaneous rashes (papules, plaques) and arthralgia. Sweet's syndrome has particularly been described in association with neoplastic, infectious and immunological diseases. The pathogenesis of Sweet's syndrome can be explained by a reaction to an antigenic structure with accumulation of immunological complexes and liberation of inflammatory mediators. For the first time we report on a patient with Sweet's syndrome and pigmented villonodular synovitis, which is believed to play the antigenic role in the Sweet syndrome.

Humans↗
PubMed2002

Electrocoagulation extends the indication of calcium hydroxide pulpotomy in the primary dentition.

The primary molars received calcium hydroxide pulpotomy with or without the electrocoagulation procedure. Teeth were evaluated clinically and radiographically at 6, 12, and 24 months after treatment. There was no statistically significant difference in success rate between calcium hydroxide pulpotomies, with and without the electrocoagulation procedure, either clinically or radiographically. These results indicate that a pulpotomy with calcium hydroxide is an effective treatment for cariously exposed pulp in primary molars and electrocoagulation can extend its indication.

Calcium Hydroxide↗
PubMed2001

The multicentric epitheloid hemangioendothelioma of bone: a case example and review of the literature.

Epitheloid hemangioendothelioma of bone is a rare primary bone malignancy. Diagnosis can be difficult for physicians who are not experienced with bone neoplasms. We also had difficulties in diagnosis and treatment in one of our patients with a multicentric epitheloid hemangioendothelioma involving the pelvis, left femur, and left tibia. We recommend a complete skeletal survey with magnetic resonance imaging because it can reveal previously undetected lesions on conventional radiographs. We performed an extraarticular resection of the hip joint including the spina iliaca anterior inferior, resection of the femur, and amputation of the lower leg. The femur was replaced by a modular endoprosthesis. The patient is provided with an above-knee prosthesis and is able to walk even longer distances with a cane 2 years after surgery. In our opinion it is necessary to perform a wide resection of this tumour in order to treat a patient with curative intention. Palliative radiotherapy should only be used for a non-resectable tumour or in metastatic disease. Chemotherapy is not a treatment option.

Adult↗
PubMed2001

FR226807: a potent and selective phosphodiesterase type 5 inhibitor.

We describe the pharmacological characteristics of a novel phosphodiesterase type 5 inhibitor FR226807, N-(3,4-dimethoxybenzyl)-2-[[(1R)-2-hydroxy-1-methylethyl]amino]-5-nitrobenzamide. FR226807 inhibited phosphodiesterase type 5 isolated from human platelets with an IC(50) value of 1.1 nM. FR226807 also inhibited phosphodiesterase type 6 with an IC(50) of 20 nM; however, the IC(50) value for phosphodiesterase type 6 was 18-fold higher than that for phosphodiesterase type 5. The IC(50) values of FR226807 for other phosphodiesterases (phosphodiesterase type 1, phosphodiesterase type 2, phosphodiesterase type 3, and phosphodiesterase type 4) were 1000-fold higher than that for phosphodiesterase type 5. FR226807 increased the cyclic guanosine monophosphate (cGMP) content in corpus cavernosum isolated from rabbit, an effect associated with relaxation of the muscle. FR226807 enhanced the relaxation response induced by electrical field stimulation of corpus cavernosum isolated from the rabbit. In an anesthetized dog model for the evaluation of erectile function, intravenous administration of FR226807 prolonged the time to return to 75% of maximal intracavernosal pressure after cessation of electrical stimulation of the pelvic nerve. In summary, FR226807 is a potent and highly selective phosphodiesterase type 5 inhibitor with an augmentative effect on penile erection and will be useful for the treatment of erectile dysfunction.

3',5'-Cyclic-GMP Phosphodiesterases↗