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T Shibuya

Publications and source records attributed to T Shibuya.

At least 37 records · Page 2Linked to original sources
PubMed2001

Iridial pigmentation induced by latanoprost ophthalmic solution in Japanese glaucoma patients.

PURPOSE: To investigate the incidence of iridial pigmentation induced by latanoprost ophthalmic solution in Japanese glaucoma patients by a prospective and observer-masked study. PATIENTS AND METHODS: Sixty-nine eyes of 69 glaucoma patients were included. Patients who had undergone intraocular surgery, laser trabeculoplasty, and laser iridotomy within 12 months before enrollment, and patients with history of uveitis and any changes in antiglaucoma drugs within 6 months before enrollment were excluded. Iridial photographs were taken by one examiner under the same conditions at 1, 3, and 6 months after the initiation of latanoprost treatment. Three glaucoma specialists, masked of patient information, independently assessed the iridial pigmentation. Cases with iridial pigmentation diagnosed by three specialists were categorized as showing a definite increase in iridial pigmentation. RESULTS: A definite increase in iridial pigmentation occurred in 3.5%, 9.7%, and 35.0% of eyes within 1, 3, and 6 months of treatment, respectively. Age, gender, or concomitantly used eyedrops did not significantly influence the incidence of iridial pigmentation within 6 months of instillation. A reduction of intraocular pressure by latanoprost did not differ significantly between patients with and without iridial pigmentation. CONCLUSION: The incidence of iridial pigmentation by latanoprost ophthalmic solution in Japanese patients was higher than previously reported values in pigmented races.

Adult↗
PubMed2001

Demonstration of genome DNA diversity of strains of urease-positive thermophilic Campylobacter isolated from the natural environment by pulsed-field gel electrophoresis analysis.

Pulsed-field gel electrophoresis (PFGE) analysis was carried out after separate digestion with Apa I, Sal I and Sma I of the genomic DNA from sixteen isolates of urease-positive thermophilic Campylobacter (UPTC) obtained from the natural environment, namely from oysters and mussels, in Northern Ireland. Five NCTC strains previously isolated in England were used for the analysis. Although the eight isolates of UPTC in Northern Ireland and a strain of UPTC in England showed that one or no fragments appeared after digestion with Apa I around 1,900 to 1,640 kb region of the gel, Apa I was shown to cut the genomic DNA from all of the other twelve strains of UPTC and Sal I and Sma I from all of the 21 strains in a distinctly different and distinguishable manner. Consequently, the present study clearly demonstrated that the sixteen isolates of UPTC in Northern Ireland and the five strains in England gave the diversity of the genomic DNA by using PFGE. Some strains of UPTC examined were shown to carry genomes from 1.6 to 1.9 Mb in length, thus the heterogeneous profiles of PFGE and the length of the genomes are thought to occur among the isolates of UPTC in Northern Ireland, as well as among the five representative strains of UPTC from NCTC.

Animals↗
PubMed2001

Preliminary psychologic survey of orofacial outpatients. Part 1: Predictors of anxiety or depression.

AIMS: To identify predictors for anxiety and depression in orofacial outpatients and to investigate the patients' compliance rate in taking a series of psychologic tests. METHODS: Three thousand six hundred sixty-six patients completed a battery of questionnaires. These consisted of items inquiring about sex, age, past history of disease, presence of pain, the Hospital Anxiety and Depression Scale (HADS), the Eysenck Personality Questionnaire Short Form (S-EPQ), a Japanese dental version of the McGill Pain Questionnaire (JDMPQ), a visual analog scale (VAS) of pain, pain duration, and diagnosis. After univariate analyses had determined those variables with significant differences between an over-probable group (OPG, HADS scores > or = 8) and an absent group (AG, HADS scores < 8), we estimated the odds ratios of these variables for OPG as independent variables, and every variable was adjusted between the independent variables by multiple logistic regression models. RESULTS: For anxiety, 3 variables were independently related to the OPG and considered to be meaningful: age 30 or older, neuroticism score on the S-EPQ, and selection of the JDMPQ pain expression term "sickening." For depression, 4 variables were independently related to the OPG and considered to be meaningful: age 30 or older, neuroticism and extroversion scores on the S-EPQ, and selection of the JDMPQ pain expression term "sickening." The compliance rate for the tests was under half of the patients (3,666 of 7,542 patients). CONCLUSION: Although the predictability for anxiety or depression by some baseline parameters is considered to be low, age, personality traits, and choice of certain pain expression terms are useful predictors of anxiety or depression. The improvement of the compliance rate for psychologic screening will be a future challenge for Japanese clinics managing orofacial patients.

Adult↗
PubMed2001

[Follow-up study of myasthenia gravis: evaluation of thymectomy in 300 patients].

From June 1975 to March 1999, 300 patients of myasthenia gravis(MG) have undergone thymectomy. Among these patients, 69 cases were classified as ocular type of MG(including 15 cases with thymoma), and 231 were generalized type of MG(including 86 cases with thymoma). The efficacy of the treatment was investigated by evaluating current patients' life activity, which is classified in 6 groups(Remission, Much Improved, Improved, Unchanged, Worse, and Died). Among the 214 cases without thymoma, Remission was 75, Much Improved was 56, and Improved was 55, namely 86.9% of these cases showed Improved or better. Among 86 cases with thymoma, Remission was 14, Much Improved was 21, and Improved was 32, namely 77.9% of these cases showed Improved or better. We concluded that post-operative outcome of these patients regardless of thymoma were generally satisfactory, but it was necessary to carry out long term careful follow-up.

Adolescent↗
PubMed2001

Indexing huge genome sequences for solving various problems.

Because of the increase in the size of genome sequence databases, the importance of indexing the sequences for fast queries grows. Suffix trees and suffix arrays are used for simple queries. However these are not suitable for complicated queries from huge amount of sequences because the indices are stored in disk which has slow access speed. We propose storing the indices in memory in a compressed form. We use the compressed suffix array. It compactly stores the suffix array at the cost of theoretically a small slowdown in access speed. We experimentally show that the overhead of using the compressed suffix array is reasonable in practice. We also propose an approximate string matching algorithm which is suitable for the compressed suffix array. Furthermore, we have constructed the compressed suffix array of the whole human genome. Because its size is about 2G bytes, a workstation can handle the search index for the whole data in main memory, which will accelerate the speed of solving various problems in genome informatics.

Abstracting and Indexing↗
PubMed2000

Progression of head and neck cancer in an in vitro model.

OBJECTIVE: To identify alterations in angiogenesis and cell cycle regulation as preneoplastic cells progress to cancer in an in vitro model of head and neck tumor progression. METHODS: Immortal human gingival keratinocyte (IHGK) cells (preneoplastic) were derived from normal oral keratinocytes and were immortalized with human papillomavirus 16. Transformation of IHGK cells with a carcinogen (NNK, 4-[methylnitrosamino]-1-[3-pyridyl]-1-butanone) gave rise to IHGKN cells. We determined the growth rates, cell cycle phase, expression of cell cycle regulators, and expression of vascular endothelial growth factor along with the organotypic features of these cells and compared them with characteristics of head and neck cancer cells. RESULTS: IHGK and IHGKN cells grown in raft culture were morphologically similar to severe dysplasia and carcinoma, respectively. The proportion of cells in G(0)/G(1) was similar between IHGK and IHGKN. However, the proportion of IHGK cells was 35% greater in S phase as compared with the IHGKN cells, while a greater percentage (40%) of IHGKN cells were in G(2)/M. The expression of the other cell cycle regulators tested was unchanged. IHGK cells secreted less vascular endothelial growth factor on day 1 when compared with IHGKN (50.6 vs 245.6 pg/mL), along with a lower overall production rate (79% vs 133%). CONCLUSIONS: Transformation of IHGK cells resulted in the activation of vascular endothelial growth factor associated with angiogenesis. Inactivation of the G(1) cell cycle regulation occurred during immortalization and before transformation, and was sustained after carcinogen exposure. These alterations correspond to changes observed in patients with head and neck squamous cell carcinoma. This model can be useful in testing novel therapeutic and preventive strategies.

Blotting, Western↗
PubMed2000

Augmentation of cancellous screw fixation with hydroxyapatite composite resin (CAP) in vivo.

The fixation of fractured bone with screws is important for orthopedic surgery, however, rigid fixation often cannot be attained in elderly patients with osteoporosis. Recently, we developed a new injectable, nonresorbable bone cement (CAP) that possesses mechanical and biological properties superior to those of polymethylmethacrylate (PMMA) cement. CAP can directly bond with bone without intervening fibrous tissue, and the peak curing temperature is 46 degrees C. In this study, we assessed the effects of CAP and PMMA cement on the augmentation of screw fixation in vivo. A cancellous screw was placed in the proximal metaphysis of rabbit tibiae. One side of each tibia was randomly selected to be augmented with CAP or PMMA. The contralateral side received a screw without cement (control). Of the 36 rabbits included in this study, 9 rabbits from each group were sacrificed and the tibial constructs retrieved 1 or 3 months after the initial operation. The screws were then pulled out to failure. The values of the pullout force of the screws augmented with CAP and PMMA were higher than those of the control specimens at both 1 month (319 +/- 58 N for CAP vs. 105 +/- 41 N for control; p < 0.05, 284 +/- 100 N for PMMA vs. 132 +/- 71 N for control; p < 0.05) and 3 months (387 +/- 109 N for CAP vs. 196 +/- 107 N for control; p < 0.05, 372 +/- 145 N for PMMA vs. 242 +/- 100 N for control; p > 0.05) after the operation. However, the average increase in the pullout force between CAP and PMMA augmentation was not statistically significant at either time. The values of energy absorption augmented with CAP and PMMA were also higher than those of the control specimens at both 1 month (129 +/- 54 N*mm for CAP vs. 19 +/- 10 N*mm for control; p < 0.05, 145 +/- 95 N*mm for PMMA vs. 28 +/- 21 N*mm for control; p < 0.05) and 3 months (172 +/- 58 N*mm for CAP vs. 44 +/- 41N*mm for control; p < 0.05, 185 +/- 198 N*mm for PMMA vs. 67 +/- 49N*mm for control; p > 0.05) after the operation. However, there were also no significant differences in energy absorption between the two types of cement augmentation. On the other hand, a significant increase was not observed in stiffness among the CAP, PMMA, and respective control groups at either 1 month (626 +/- 133 N/mm for CAP vs. 441 +/- 180 N/mm for control; p < 0.05, 577 +/- 87 N/mm for PMMA vs. 450 +/- 121 N/mm for control; p > 0.05) or 3 months (622 +/- 144 N/mm for CAP vs. 600 +/- 204 N/mm for control; p > 0.05, 633 +/- 175 N/mm for PMMA vs. 630 +/- 168 N/mm for control; p > 0.05) after the operation, except in the average increase between CAP augmentation and its control 1 month after the operation. These results suggested that a cancellous screw fixation augmented with CAP, as well as PMMA, was effective compared with the unaugmented control in vivo. Because of its biocompatibility and low curing temperature, CAP can be used clinically to augment cancellous screw fixation.

Animals↗
PubMed2000

Mechanical evaluation of a bio-active bone cement for total hip arthroplasty.

A new bio-active bone cement, known as CAP, has been developed as an alternative to acrylic bone cement. CAP has improved mechanical properties, with a high modulus that is over five times that of PMMA. The effects of this high modulus are examined by finite element analysis, when the CAP is used in place of PMMA to fix the femoral component in total hip prostheses. The results show a higher tensile stress of 8.76 MPa in the CAP cement, compared with 1.99 MPa in the PMMA cement. However, it is also shown that CAP has a superior fatigue strength of approximately 40 MPa, obtained from a cyclic loading test.

Arthroplasty, Replacement, Hip↗
PubMed2000

Aclarubicin induces differentiation of leukemic progenitors in myelodysplastic syndrome cooperating with granulocyte colony-stimulating factor.

We have reported that low-dose aclarubicin (ACR) therapy is effective in some patients with myelodysplastic syndrome (MDS). Here, we demonstrate that a low concentration of ACR induces the in vitro differentiation of leukemic progenitor cells from patients with MDS. ACR (0.1 ng/ml) significantly increased the number of granulocyte colony-stimulating factor (G-CSF)-dependent colonies from circulating blast cells in vitro in six out of seven MDS patients with refractory anemia with excess of blast in transformation or chronic myelomonocytic leukemia, but not in all four patients with primary acute myelogenous leukemia. In these MDS patients, the effect of ACR gradually disappeared along with the progression of MDS. Interestingly, the majority of G-CSF/ACR-dependent colonies consisted of rather differentiated myeloid cells such as myelocytes and metamyelocytes, whereas colonies formed by G-CSF alone were composed mainly of immature blastic cells. The number of G-CSF-responding progenitors significantly increased during a 24-48 h incubation with ACR alone. The circulating blasts in MDS patients expressed G-CSF receptors at unchanged levels before and after the incubation with ACR. It is suggested that ACR might increase clonogenic progenitor responsiveness to G-CSF in MDS, probably through modulating downstream signaling cascades associated with G-CSF receptors, and induce these progenitors to differentiate in response to G-CSF.

Aclarubicin↗
PubMed2000

Videostroboscopy of the pharyngoesophageal segment in laryngectomy patients treated with botulinum toxin.

OBJECTIVES: The purpose of this investigation was to use videostroboscopy to study the physiologic and biomechanical effects of botulinum toxin (Botox) injection on the pharyngoesophageal segment (PES) in total laryngectomy patients with poor-quality tracheoesophageal puncture (TEP) voice caused by PES spasm. METHODS: The following was a prospective study. Videostroboscopy of the PES and videotaped recordings of patients performing TEP voice tasks were conducted before and after Botox injection of the PES. Ratings of videostroboscopic and speech samples were performed by 3 blinded judges with extensive experience with this patient population. RESULTS: Perceptually, TEP voice was more fluent and less strained after injection. Videostroboscopically, patients demonstrated improved PES volitional control and mucosal wave characteristics after Botox injection. CONCLUSION: Botox injection in total laryngectomy patients with poor-quality TEP voice caused by PES spasm provides improved physiologic and biomechanical function of the PES, as demonstrated for the first time videostroboscopically. These findings help explain the perceptual ratings of TEP voice improvement noted after Botox injection. Videostroboscopy can be used to provide diagnostic information to help confirm the clinical impression of PES spasm, as well as to document the effects of Botox injection on PES function.

Adult↗
PubMed2000

Synovial chondromatosis of the left temporomandibular joint superficially resembling chondrosarcoma: a case report.

A 25 year-old woman was referred to the clinic complaining of pain in the left temporomandibular joint (TMJ) and trismus. According to the x-ray images, a solitary mass was observed in the anterior pouch of the lower joint cavity. The mass was removed by means of a synovectomy and a diskectomy. Upon light microscopic examination, the tissue removed showed high cellular activity. As a differential diagnosis, we had to consider the possibility of chondrosarcoma based on the histopathological features; however, since no invasive nor metastatic finding was recognized, we made a diagnosis of synovial chondromatosis despite its rare existence. Although there has been no sign of recurrence at present, we plan to carefully follow up with the patient.

Adult↗
PubMed2000

A case of aortic dissection with transient ST-segment elevation due to functional left main coronary artery obstruction.

A 48-year-old man with a history of hypertension and diabetes mellitus was hospitalized with sudden onset of severe chest pain. He was in cardiogenic shock with a systolic pressure of 60 mm Hg. His electrocardiogram (ECG) showed ST-segment elevation in the precordial leads suggestive of acute anteroseptal myocardial infarction. The ST-segment returned to baseline after the systolic blood pressure rose to 100 mm Hg with the administration of sympathomimetic agents. Aortography and transesophageal echocardiography demonstrated type A aortic dissection and aortic regurgitation. Aortography and short-axis transesophageal echocardiography showed during diastole almost complete collapse of the true lumen of the ascending aorta caused by the intimal flap. The patient underwent surgical repair of the aortic dissection and implantation of Palmaz stents in the carotid arteries. Decreased blood pressure and the presence of aortic regurgitation accelerated the collapse of the true lumen during diastole in the ascending aorta, resulting in functional obstruction of the left main coronary artery, which may have been related to ST-segment changes in this case.

Aortic Dissection↗
PubMed2000

Anti-malarial activity of leaf-extract of hydrangea macrophylla, a common Japanese plant.

To find a new anti-malarial medicine derived from natural resources, we examined the leaves of 13 common Japanese plants in vitro. Among them, a leaf-extract of Hydrangea macrophylla, a common Japanese flower, inhibited the parasitic growth of Plasmodium falciparum. The IC50 of Hydrangea macrophylla leaf extract to Plasmodium falciparum was 0.18 microg/ml. The IC50 to NIH 3T3-3 cells, from a normal mouse cell line, was 7.2 microg/ml. Thus, selective toxicity was 40. For the in vivo test, we inoculated Plasmodium berghei, a rodent malaria parasite, to ddY mice and administered the leaf-extract of Hydrangea macrophylla (3.6 mg/0.2 ml) orally 3 times a day for 3 days. Malaria parasites did not appear in the blood of in the treated mice, but they did appear in the control group on day 3 or 4 after inoculation with the parasites. When leaf extract was administered to 5 mice 2 times a day for 3 days, malaria parasites did not appear in 4 of the mice but did appear in 1 mouse. In addition, the leaf-extract was administered orally 3 times a day for 3 days to Plasmodium berghei infected mice with a parasitemia of 2.7%. In the latter group, malaria parasites disappeared on day 3 after initiating the treatment, but they appeared again after day 5 or 6. Although we could not cure the mice entirely, we confirmed that the Hydrangea macrophylla leaf extract did contain an anti-malarial substance that can be administered orally.

Animals↗
PubMed2000

Short report: study on the efficacy of a new long-acting formulation of N, N-diethyl-m-toluamide (DEET) for the prevention of tick attachment.

The beneficial effects of N, N-diethyl-m-toluamide (DEET) against biting insects of human and animals appear to last <6 hr after a single application to the skin. To prolong the repellent effects of DEET, recently we developed a new long-acting formulation of DEET called LIPODEET. This preparation was retained in the skin for a longer duration of time with minimal systemic absorption. In this study, we have evaluated the protective effect of three compounds (DEET, LIPODEET, and Morpel 220) against attachment of two species of ticks (Amblyomma americanum and Dermacentor variabilis) to rabbit ears. Results show that LIPODEET and Morpel 220 were highly effective in preventing tick attachment to the skin for a longer duration of time (up to 72 hr) than DEET after a single application. Moreover, LIPODEET was found to be acaricidal to both the species of ticks.

Animals↗
PubMed1999

Deletion of the carboxyl-terminal exons of K-sam/FGFR2 by short homology-mediated recombination, generating preferential expression of specific messenger RNAs.

The K-sam gene was first identified as an amplified gene from human gastric cancer cell line KATOIII, and its product is identical to fibroblast growth factor receptor 2. The K-sam gene is located on human chromosome 10q26 and is preferentially amplified in the poorly differentiated types, especially in the scirrhous type, of gastric cancers. During the course of studies on the structural characterization of the amplification units, we found that the carboxyl-terminal exons of K-sam were deleted in three of four of the scirrhous type of gastric cancer cell lines. These deletions generate preferential expression of mRNAs encoding K-sam proteins lacking the carboxyl-terminal region containing the tyrosine residues at positions 780, 784, and 813. The carboxyl-terminal region has been reported to have a sequence required for the inhibition of NIH3T3 transformation, indicating that cells with amplification of the truncated K-sam gene have a growth advantage during the carcinogenic process for the scirrhous type of gastric cancers. This is the first report showing the deletion of the carboxyl-terminal exons of the receptor-type of the protein tyrosine kinase gene. Sequence analysis of the DNA sequences surrounding the deletion junctions shows the presence of unique sequences and indicates the involvement of short homology-mediated recombination in the generation of these deletions.

3T3 Cells↗
PubMed1999

Mutation induction by N-propyl-N-nitrosourea in eight MutaMouse organs.

As a part of the 2nd Collaborative Study for the Transgenic Mouse Mutation Assay, we studied the organ specificity and the temporal changes in mutant frequency (MF) of the lacZ gene following intraperitoneal injection of 250 mg/kg N-propyl-N-nitrosourea into male MutaMouse. We used a positive selection system and examined eight organs, i.e., bone marrow, liver, kidney, lung, spleen, brain, heart, and testis. The chemical caused a significant increase in MF in all organs except for brain, and the bone marrow was the most sensitive organ, exhibiting a MF on day 7 that was 10 times that of the control. The MF increased from day 7 to day 28 in liver, kidney, and testis, while it decreased in bone marrow. The relationship between the results of this study and the target organs of carcinogenesis, and the cause of the temporal changes in MF, are discussed.

Animals↗