Biomedical subjects

S Kariya

Publications and source records attributed to S Kariya.

At least 19 recordsLinked to original sources

PubMed2001

Ménière's disease in childhood.

We report 3 rare cases of Ménière's disease in children. In Case 1 and 3, vertigo, hearing loss and tinnitus recovered soon after medical therapy. In Case 2, however, vertigo recurred and the hearing level on the right side markedly deteriorated. The equal-loudness contours on three-dimensional audiogram showed that right-sided aggravated hearing loss fluctuated for 4 years at middle-and low-frequencies despite medication. Finally intratympanic injection of gentamicin sulfate was performed. The patient has had no definitive spell of vertigo after gentamicin therapy. At our department, the incidence of Ménière's disease in pediatric patients with vertigo was 2.9%.

Adolescent↗

PubMed2001

[No relation between angiotensin-converting enzyme (ACE) inhibitor-induced cough and ACE gene polymorphism, plasma bradykinin, substance P and ACE inhibitor concentration in Japanese patients].

Persistent dry cough is well known as the most common side-effect of angiotensin-converting enzyme (ACE) inhibitors. We examined the relationship between a cough and ACE gene polymorphism, plasma bradykinin (BK), substance P (SP) and ACE inhibitor concentrations in patients with hypertension or chronic nephritis. First, ACE genotyping was carried out in 96 patients, 42 with coughs and 54 without coughs, which had been treated with various kinds of ACE inhibitors. However, no significant difference in the ACE genotypes was observed between the two groups. Second, the plasma concentrations of BK, SP and ACE inhibitor were measured in 12 patients, which were treated with trandolapril at a daily dose of 1 mg for 4-33 weeks. In 3 patients, the cough was induced during the trandolapril therapy, while it was induced not in 9 patients. The plasma levels of BK and SP did not significantly change after trandolapril administration in the patients with and without coughs. Between the two groups, there were no significant differences in the plasma levels of BK and SP either before or after the trandolapril therapy. Also the plasma concentrations of trandolapril and trandolaprilat, the active metabolite of trandolapril, did not significantly differ between the two groups. These results suggest that there is no significant relationship between the ACE inhibitor-induced cough and ACE gene polymorphism, plasma BK, SP and ACE inhibitor concentrations in patients with hypertension or chronic nephritis.

Aged↗

PubMed2001

Radiation-induced apoptosis of human peripheral T cells: analyses with cDNA expression arrays and mitochondrial membrane potential assay.

We examined sequential changes in post-irradiated peripheral blood T cells taken from normal volunteers, by using targeted Atlas cDNA Expression Arrays and mitochondrial membrane potential assay. At 1 and 3 hours after 5 Gy irradiation, changes of gene expression were examined by targeted Atlas cDNA Expression Arrays using Apoptosis Array. The Atlas Human Apoptosis Array includes 205 key genes that are known to control apoptosis, including extracellular and cytoplasmic effectors. Concerning Fas, no significant changes of spot intensities were identified between irradiated T cells and non-irradiated ones at both 1 h and 3 h after 5 Gy irradiation. Caspase families, including caspases 9 and 3 also showed no changes between these two groups. An apoptosis regulator bclw showed a remarkable decrease in irradiated T cells. These results suggested that irradiation induced direct apoptosis of T cells by changing the membrane potential of mitochondria. Using a CCD camera-equipped fluorescence microscope and MitoCapture, a mitochondrial membrane potential indicator, we demonstrated 5 Gy radiation induced loss of membrane potential, i.e., an early stage of apoptosis, in human peripheral blood T cells at 10 hours after irradiation.

Apoptosis↗

PubMed2001

Early reduction in the aneuploidy at chromosomes 7 and 8 are significantly correlated with clinical effect in high-dose rate brachytherapy with external beam radiotherapy in localized prostate cancer.

Although reduction in the serum prostate specific antigen (PSA) correlates with clinical outcome for high dose rate Iridium-192 (HDR Ir-192) brachytherapy, it takes a long latency period. We investigated numerical chromosome changes of prostatic cancer during the pre- and post-treatment periods of HDR Ir-192 brachytherapy (and external beam radiotherapy), using fluorescence in situ hybridization (FISH) to clear the effect of treatment in early phase. Transitional changes in the frequency of aneuploidy for chromosomes 7, 8, 10, 12, 16, X, and Y in prostate cancer during the pre- and post-treatment periods were observed. Gains of chromosomes 7, 8 and 12 were noted in the pre-treatment samples (4 out of 12 cases in chromosomes 7 and 8; 1 out of 12 cases in chromosome 12), while a notable reduction in the number of cells with extra copies of these chromosomes was observed in post-treatment specimens. This change appears earlier than the reduction in the value of prostate specific antigen (PSA) and strongly reflects the effect of HDR brachytherapy with external beam radiotherapy in localized prostate cancer. Decrease in the number of cells with high ploidies of chromosomes 7, 8 and 12 at 12 weeks after treatment may predict clinical effects of radiation therapy, which may explain the radiation dependency of localized prostate cancer cells.

Aged↗

PubMed2001

[High-dose rate Iridium-192 brachytherapy with flexible applicator--a trial toward decrease of stress during treatment and improvement of quality of life].

PURPOSE: We tried to improve the materials and methods of high-dose rate Iridium-192 brachytherapy for localized prostate cancer and evaluated the stress during the treatment in 20 patients with whom the therapy was performed. MATERIALS AND METHODS: Rigid applicators made of stainless steel of 1.6 mm in diameter were indwelt with a template as usual for 30 hours in 14 patients (group A). Flexible applicators made of polyoxymethylene rosin (POM) of 2.0 mm in diameter were indwelt without a template for 30 hours after the applicator insertion in 6 patients (group B). We made inquiries about lumbago, inconvenience and necessity of assistant help and sleep in the course of therapy, and urinary incontinence and erectile function after the course of therapy as the QOL. RESULTS: The stress during the course of therapy in the patients of group B was obviously less than that of group A. There were no significant differences in urinary incontinence and erectile function after the course of therapy between group A and B. CONCLUSION: In this study, our trial successfully reduced the stress during the course of therapy in the patients with localized prostate cancer in the course of high-dose rate Iridium-192 brachytherapy.

Aged↗

PubMed2001

[High-dose rate iridium-192 brachytherapy combined with external beam radiotherapy for localized prostate cancer].

PURPOSE: We report our technique and also preliminary results in the cases with localized prostate cancer treated by the combination of high-dose rate Iridium-192 (HDR-Ir192) brachytherapy and external irradiation. MATERIALS AND METHODS: From June 1999 to August 2000, 17 patients were treated by the combination of HDR-Ir 192 and external beam. The mean age of patients was 72 years (range, 48-81 years). The clinical stage was B1 in 5, B2 in 7 and C (no cancer with seminal vesicle) in 5 cases. Of 10 patients without neoadjuvant hormonal therapy, the median initial pretreatment PSA was 15.3 ng/ml (6.93-222.32 ng/ml). The treatment was given by HDR-Ir 192 brachytherapy (6 Gy x 3 times/2 days) and external beam irradiation (40 or 45 Gy). The brachytherapy was given using TRUS guided percutaneously inserted temporary needles with a high dose rate remote afterloading control. Local control was evaluated by digital rectal examination. TRUS-guided biopsies and serum PSA evaluations. Follow-up ranged from 2 to 14 months, with a median of 8 months. RESULTS: In 4 (40.0%) of 10 patients without neoadjuvant hormonal therapy the level of serum PSA was decreased to less than 4.0 ng/ml within 3 months after the therapy. The effective grade in the biopsy specimens of 8 patients without neoadjuvant hormonal therapy was Grade Ob in 4, Grade 1 in 1, Grade 3 in 3 cases at 3 months after the therapy. No severe intra- or peri-operative complications occurred. CONCLUSION: The combined radiotherapy treatment is safe and effective for use in the patients with localized prostate cancer. However, more comprehensive studies involving long-term follow-up and great numbers of the cases with localized prostate cancer treated by the combination of HDR-Ir 192 brachytherapy and external irradiation will be necessary to determine whether this therapy contributes to better prognosis.

Aged↗

PubMed2001

Involvement of CYP2B6 in n-demethylation of ketamine in human liver microsomes.

Ketamine is metabolized by cytochrome P450 (CYP) leading to production of pharmacologically active products and contributing to drug excretion. We identified the CYP enzymes involved in the N-demethylation of ketamine enantiomers using pooled human liver microsomes and microsomes from human B-lymphoblastoid cells that expressed CYP enzymes. The kinetic data in human liver microsomes for the (R)- and (S)-ketamine N-demethylase activities could be analyzed as two-enzyme systems. The K(m) values were 31 and 496 microM for (R)-ketamine, and 24 and 444 microM for (S)-ketamine. Among the 12 cDNA-expressed CYP enzymes examined, CYP2B6, CYP2C9, and CYP3A4 showed high activities for the N-demethylation of both enantiomers at the substrate concentration of 1 mM. CYP2B6 had the lowest K(m) value for the N-demethylation of (R)- and (S)-ketamine (74 and 44 microM, respectively). Also, the intrinsic clearance (CL(int): V(max)/K(m)) of CYP2B6 for the N-demethylation of both enantiomers were 7 to 13 times higher than those of CYP2C9 and CYP3A4. Orphenadrine (CYP2B6 inhibitor, 500 microM) and sulfaphenazole (CYP2C9 inhibitor, 100 microM) inhibited the N-demethylase activities for both enantiomers (5 microM) in human liver microsomes by 60 to 70%, whereas cyclosporin A (CYP3A4 inhibitor, 100 microM) failed to inhibit these activities. In addition, the anti-CYP2B6 antibody inhibited these activities in human liver microsomes by 80%, whereas anti-CYP2C antibody and anti-CYP3A4 antibody failed to inhibit these activities. These results suggest that the high affinity/low capacity enzyme in human liver microsomes is mediated by CYP2B6, and the low affinity/high capacity enzyme is mediated by CYP2C9 and CYP3A4. CYP2B6 mainly mediates the N-demethylation of (R)- and (S)-ketamine in human liver microsomes at therapeutic concentrations (5 microM).

Aryl Hydrocarbon Hydroxylases↗

PubMed2000

A terminal deletion of the short arm of chromosome 3: karyotype 46, XY, del (3) (p25-pter); a case report and literature review.

We describe a boy with a deletion of the short arm of chromosome 3; (46, XY, del (3) (p25-pter) who presented several minor craniofacial anomalies at birth. Only 34 cases of small distal 3p deletion have been described in the literature, seven of them showed hearing loss and four of the 34 cases had brain anomalies. But in none of the 34 cases the middle and internal ear were radiographically examined. Despite the severe hearing loss detected by auditory brainstem evoked responses (ABR), computerized tomographic scanning (CT-scan) of the ear showed a normal anatomy in this patient. The head CT-scan and magnetic resonance imaging (MRI) disclosed a hypoplastic corpus callosum and an enlargement of the lateral ventricles.

Brain↗

PubMed2000

A case of infantile neuroblastoma with intramucosal metastasis in a paranasal sinus.

An 8-year-old boy with neuroblastoma of the right adrenal gland is reported. His initial treatment included chemotherapy and surgery, with complete response (CR) being achieved at the initial site. A metastatic lesion was found in the right maxillary sinus 32 months after his initial treatment. A mass in the right soft palate was detected and was clinically suspected of being a metastasis. The results of biopsy were negative and the differential diagnosis from the imaging studies of CT included odontogenic disease, fungal infection, paranasal sinus cyst or hematoma, and benign tumors. Open transantral biopsy was done under general anesthesia, revealing severe inflammation in the right maxillary sinus as well as bone erosion. The histopathological diagnosis was metastatic neuroblastoma from the adrenal lesion. The local field was irradiated with 20 Gy of linear accelerator (linac) radiation, then the local field was eradicated. Extensive skeletal metastases were subsequently found by bone scintigraphy. Despite further treatment his general condition deteriorated rapidly and he died 24 months after starting treatment. We review the previous reports and discuss metastasis to the sinuses.

Adrenal Gland Neoplasms↗

PubMed2000

Stereoselective high-performance liquid chromatographic determination of ketamine and its active metabolite, norketamine, in human plasma.

A stereoselective high-performance liquid chromatographic method for the determination of the enantiomers of ketamine and its active metabolite, norketamine, in human plasma is described. The compounds were extracted from plasma by liquid-liquid extraction three times in a combination of cyclohexane with 2.5 M NaOH, 1 mM HCl and 1 M carbonate buffer. Stereoselective separation was achieved on a Chiralcel OD column with a mobile phase of n-hexane-2-propanol (98:2, v/v). The detection wavelength was 215 nm. The lower limits of the determination of the method were 5 ng/ml for ketamine and 10 ng/ml for norketamine. The intra- and inter-day coefficients of variation ranged from 2.9 to 9.8% and from 3.4 to 10.7% for all compounds, respectively. The method was sensitive and sufficiently reproducible for stereoselective monitoring of ketamine and norketamine in human plasma during pharmacokinetic studies after the administration of ketamine for analgesia.

Adult↗

PubMed2000

Toremifene-induced fatty liver and NASH in breast cancer patients with breast-conservation treatment.

We have described fatty liver, diagnosed by computed tomography scanning (CT) in more than 30% of patients with breast cancer who received tamoxifen. Therefore, it is urgent to elucidate the frequency and the degree of fatty liver induced by toremifene, an analogue of tamoxifen, which is also used in breast cancer. We enrolled 52 breast cancer patients who were treated with breast-conservation treatment and administered oral toremifene for 3-5 years as adjuvant endocrine therapy. We evaluated the degree of fatty liver by abdominal CT performed annually. CT demonstrated toremifene-induced fatty liver in four (7.7%) of 52 breast cancer patients. Toremifene-induced fatty liver did not correlate with abnormal levels of AST, ALT, GGT or total cholesterol. One patient who demonstrated moderate fatty liver by CT was histologically diagnosed as non-alcoholic steatohepatitis (NASH) by liver biopsy. The incidence of toremifene-induced fatty liver was significantly lower than that induced by tamoxifen. Accordingly, in terms of fatty liver and NASH, toremifene is considered to be more appropriate agent than tamoxifen. Though toremifene is less likely to induce fatty liver, the possibility remains that toremifene-induced steatohepatitis occurs. Because the diagnosis of fatty liver or NASH can be easily missed if only a blood test is performed, it is necessary to screen fatty liver by annual CT examination for patients who receive an antiestrogen agent.

Alanine Transaminase↗

PubMed2000

Ionizing radiation-induced apoptosis in human lymphoma cell lines differing in p53 status.

Most of malignant lymphomas have been shown to be relatively radiosensitive clinically, but some, especially recurrent ones, are frequently highly radioresistant. To clarify the origin of the difference, we examined ionizing radiation (IR)-induced apoptosis in three closely related human lymphoma cell lines (DL-40, DL-95, and DL-110) that differ in p53 status. DL-95 and DL-110 cells have a wild-type p53, whereas DL-40 cells carry a T to G transition in exon 5 of the p53 gene, resulting in a change of Cys to Phe at codon 176. Irradiation of DL-40 cells (mutant-type p53) with 5 Gy gamma-rays resulted in delayed apoptosis with membrane changes (annexin-V expression) 13 h after IR, and caspase-3 activation 23 h after IR, whereas apoptotic response was not identified in DL-95 cells until 48 h after IR in spite of their normal p53 status. Concerning DL-110 cells, delayed and reduced apoptotic response was revealed both microscopically and by DNA fragmentation assay. These results suggested that IR-induced apoptosis in DL-40 cells is mediated by a mechanism involving the caspase-3 cascade of the p53-independent pathway, and that some unknown mechanism inhibited IR-induced apoptosis in existence of wild-type p53, especially for DL-95 cells.

Annexin A5↗

PubMed2000

[A case of metastatic extradural seminoma suspected intradural invasion by the measurements of HCG beta concentration in CSF].

A 34-year-old man underwent left orchidectomy for his left testicular seminoma. One month later, he developed paraplegia, hypesthesia under Th10 level and vesicorectal disturbance. He was diagnosed as having compressive myelopathy secondary to metastatic neoplasm at thoracic vertebra 10 and its extradural space which were revealed on magnetic resonance imaging. After administration of combination chemotherapy with cisplatin, etoposide and bleomycin, the extradural lesions diminished and the neurological symptoms gradually improved. In this case, intradural invasion of tumor cells was suspected because the level of human chorionic gonadotrophin beta subunit (HCG beta) concentration in cerebrospinal fluid (CSF) was higher than that in plasma, while radiographic scanning demonstrated regional tumor located at extradural space of Th10 level. It is important to evaluate the spread of tumor cells for the choice of therapy and the monitoring of HCG beta (plasma:CSF ratio) was considered to be one of the useful methods to detect the presence of central nerve system metastases from HCG-producing tumor.

Adult↗

PubMed2000

[A case of multiple cavernous angioma with dementia].

We reported a 65-year-old man who developed dementia since 50 years of age. His consciousness was clear but he was indifferent to his illness. Also, the luck of attention was recognized when we underwent examinations and the result of intellectual test varied every time we performed. His memory function was almost normal on the examination which was performed when he was cooperative. Magnetic resonance imaging (MRI) disclosed multiple tiny lesions (more than 130 in all) in cerebrum, brainstem, cerebellum and spinal cord. These lesions were compatible with multiple cavernous angioma. Most of lesions manifested high-density area on cranial CT. Though the multiplicity of foci indicated the possibility of familial occurrence, he was considered to be a sporadic case on his lineage investigation and the brain MRI of his only son. In this case, neither headache nor seizures which were known as the major clinical features of intracerebral cavernous angioma was observed. He was diagnosed as having white matter dementia characterized by attentional dysfunction, decrement of volition and less memory disturbance. We speculated that he developed symptomatic dementia by the sum of multiple minor degeneration, especially in frontal lobe white matter, caused by repeated minor bleeding from cavernous angiomas.

Aged↗

PubMed1999

Late pathologic changes in guinea pig kidneys irradiated with conventional fractionation and hyperfractionation.

PURPOSE: The aim of this study was to determine the differences in renal damage particularly associated with the effect of a small dose per fraction with a constant total dose. METHODS AND MATERIALS: Guinea pigs, 12-week-old English Hartley females, were used. The animals were divided into five groups according to irradiation schedule: No irradiation (control group); 2.0 Gy x 1/day, 5 fraction (f)/week (wk), 40 f, total 80 Gy (Group CF-2.0 [CF = conventional fractionation]); 1.0 Gy x 2/day, 10 f/wk, 80 f, total 80 Gy (Group HF-1.0 [HF = hyperfractionation]); 3.0 Gy x 1/day, 5 f/wk, 27 f, total 81 Gy (Group CF-3.0); and 1.5 Gy x 2/day, 10 f/wk, 54 f, total 81 Gy (Group HF-1.5). Only unilateral irradiation was performed. A histologic analysis was performed before irradiation and at 6 and 12 months after the completion of irradiation. The severity and severity ratios of urinary tubule atrophy, the number of large nuclei per unit area in the renal tubules, the average diameter of the glomeruli, and the number of cells composing the glomerulus were used as parameters for evaluating renal damage. RESULTS: In Groups CF-2.0 and CF-3.0 (the conventional fractionation [CF] groups), all the renal tubules showed severe atrophy 12 months after irradiation. On the other hand, only 20% of the renal tubules showed slight atrophy in Group HF-1.0 at 12 months. In Group HF-1.5, 70% of the renal tubules were atrophic at 12 months. The number of large nuclei markedly increased in Groups HF-1.0 and HF-1.5 (the hyperfractionation [HF] groups) at 12 months, whereas the number was very low in the CF groups at 12 months. Only in Group HF-1.0 had the average diameter of glomeruli not shrunk at 12 months. The number of cells composing the glomerulus in the CF groups markedly decreased at 12 months. The number of cells in the HF groups was also reduced, however the reduction was not as severe as that observed in the CF groups. CONCLUSION: 1.0 Gy per fraction delivered by HF greatly reduces renal damage even in the 80 Gy-irradiated kidney, which is one of the most radiosensitive organs.

Animals↗

PubMed1999

Resistance to nitric oxide-mediated apoptosis in HL-60 variant cells is associated with increased activities of Cu,Zn-superoxide dismutase and catalase.

Nitric oxide (NO) released from (Z)-1-[N-(2-aminoethyl)-N-(2-ammonioethyl)amino]diazen-1- ium-1,2-diolate (DETA/NO or NOC-18) induces apoptosis in human leukemia HL-60 cells. In this study, we isolated a HL-60 variant cell line, HL-NR6, that is resistant to DETA/NO toxicity as assessed by DNA fragmentation, morphology, and colony forming ability. The variant cells also showed resistance to reactive oxygen species (ROS) such as superoxide and hydrogen peroxide as well as NO donors, but not to anti-tumor drugs. We found that HL-NR6 cells when compared with HL-60 cells possessed twice the activities of Cu,Zn-superoxide dismutase (Cu,Zn-SOD) and catalase, but no change in Mn-SOD nor in glutathione peroxidase. Immunoblotting confirmed the high levels of both enzymes in the variant cell. We also observed that ROS generation following DETA/NO exposure was substantially higher in HL-60 cells than in HL-NR6 cells, using the 2',7'-dichlorofluorescein fluorometric method. Moreover, the SOD mimetic Mn(III) tetrakis(1-methyl-4-pyridyl) porphyrin and exogenous catalase effectively attenuated DETA/NO-elicited DNA fragmentation in HL-60 cells. Taken together, these data suggested that the NO resistance in HL-NR6 cells is associated with the increased Cu,Zn-SOD/catalase and that NO-mediated apoptosis in HL-60 cells is correlated with the generation of ROS and derived molecules like peroxynitrite.

Apoptosis↗

PubMed1999

Extraosseous metastases of hepatocellular carcinoma detection and therapeutic assessment with Tc-99m PMT SPECT.

Owing to recent advances in imaging technology and radiologic intervention, survival rates in patients with hepatocellular carcinoma have improved markedly. However, such prolonged survival has resulted in an increase in extrahepatic metastases. Tc-99m (Sn)-N-pyridoxyl-5-methyltryptophan (Tc-99m PMT), developed for hepatobiliary scintigraphy, has been used to visualize extrahepatic metastases, with most related reports limited to osseous metastases. The authors report two cases of hepatocellular cancer presenting as a hypopharyngeal metastasis and intraperitoneal dissemination along the tract of a fine-needle biopsy. Lesions undetectable on planar imaging could be visualized by Tc-99m PMT SPECT.

Aged↗

PubMed1999

[Preparation of ketamine tablets for treatment of patients with neuropathic pain].

Ketamine is known to have distinguished analgesic effects without anesthetic when administered in a low dose. Since ketamine is not commercially available except injection forms, we prepared ketamine tablets for the home-care medication of patients with neuropathic pain. The direct compression or wet granulation method was employed to form 150 mg of tablets containing 50 mg of ketamine. The latter method was superior to the former one in terms of content uniformity, weight variation and disintegration tests of the tablets. Ketamine contents in the tablet prepared by the wet granulation method were unchanged for 12 weeks under the conditions of 25 degrees C and 75% relative humidity (RH). The Cmax and AUC0-3 h values for ketamine after administration of the tablet were slightly smaller than those of the syrup in a healthy volunteer. However, analgesic effects of the tablet was similar to that of the syrup in a patient with neuropathic pain. And the tablet was also effective for another four patients with neuropathic pain. These results indicate that ketamine tablets are useful for the home-care medication of patients with neuropathic pain.

Adult↗