Biomedical subjects

T Kubo

Publications and source records attributed to T Kubo.

At least 127 records · Page 7Linked to original sources

PubMed2001

Detoxification effect of iron-encaging zeolite-processed water in tributyltin-intoxicated Euglena gracilis Z.

In our previous paper, we reported the restoration promoting effects of mineral-encaging zeolite-processed water, especially of a Fe-encaging one, on tributyltin chloride (TBTCl)-intoxicated Euglena gracilis. This present study extends the investigation on the behavior of TBTCl and a xenobiotic enzyme, cytochrome P-450, in Euglena cells incubated with or without Fe-encaging zeolite-processed water (FeZW). Subcellular fractionation of TBTCl-intoxicated Euglena cells, atomic absorption spectrophotometry, and GC analyses showed that TBTCl was rapidly incorporated into the cells to halt cell motility. GC-MS showed that FeZW promoted conversion of TBTCl to dibutyltin (DBT) as the major metabolite in the microsomal fraction of the cells. An in vitro incubation system with heat-treated microsomes did not convert TBTCl to DBT. The contribution of cytochrome P-450 in the microsomal fraction was suggested by an immunochemical method. The results suggest that the improvement of detoxification by FeZW in the TBT-intoxicated Euglena cells should be due to activation of biotransformation system of the Euglena cells by FeZW.

Animals↗

PubMed2001

Regulation of hydroxyindole-O-methyltransferase gene expression in Japanese quail (Coturnix coturnix japonica).

Hydroxyindole-O-methyltrasferase (HIOMT) plays an important role as the final enzyme in the synthesis of melatonin. In this study, the expression of the HIOMT gene in Japanese quail was investigated with respect to tissue distribution and the effects of light and vitamin A deficiency. HIOMT mRNA in the pineal gland and eye had a clear daily rhythm with peak values in daytime. The testis also contained a detectable amount of HIOMT mRNA, which did not display a rhythmic change over a 24-h period. When birds were rendered vitamin A deficient through feeding with a vitamin A-free diet, the daily rhythm of the HIOMT gene almost disappeared in both the pineal gland and eye due to increases in the nighttime values. Our previous observations and these results suggest that vitamin A and a photo-signal are required to maintain the rhythmic expression of the HIOMT gene as well as the arylalkylamine N-acetyltransferase gene.

Acetylserotonin O-Methyltransferase↗

PubMed2001

Retinoid nutritional status differently affects the expression of Japanese quail retinoic acid receptor-beta isoform transcripts in a tissue-specific manner.

We investigated the effects of vitamin A (VA) nutritional status on the levels of expression of retinoic acid (RA) receptor-beta (RARbeta) gene in the various tissues of Japanese quail. VA deficiency caused a significant decrease in the mRNA levels of brain, liver, heart, lung and kidney RARbeta2/beta4, whereas no change was observed in the level of testis RARbeta2 transcript. In contrast, reduction in the RARbeta1 transcript caused by VA depletion was observed only in the lung, remaining unchanged in the other tissues. The administration of RA to the VA-deficient quail rapidly induced the expression of RARbeta2/beta4 mRNAs in all the tissues examined, but RA increased the expression of RARbeta1 transcript in the liver, heart, lung and kidney at a lower magnitude. RA could not change the expression of the brain RARbeta1 transcript, while it induced the expression of the testis RARbeta1 mRNA in a temporal way. These results clearly indicate that VA nutritional status differently regulates the expression of RARbeta1 and RARbeta2/beta4 transcripts in a tissue-specific manner.

Analysis of Variance↗

PubMed2001

Targeted systemic chemotherapy using magnetic liposomes with incorporated adriamycin for osteosarcoma in hamsters.

To control the growth of primary tumors effectively with systemic chemotherapy, we recently developed intravenously administered small-sized magnetic liposomes as an anticancer drug carrier. We previously reported that intravenously administered magnetic liposomes with incorporated adriamycin (magnetic ADR liposomes) effectively delivered ADR to the target site where a permanent magnet was implanted. In the present study, the therapeutic efficacy of this novel treatment approach, which involves a combination of magnet implantation at the target site and intravenous administration of magnetic liposomes, was further evaluated by comparing tumor growth rates among different administration modalities and by histological examination of treated tumors. Small-sized magnetic ADR liposomes with a mean diameter of 146 nm were prepared by the reverse-phase evaporation method. Syrian male hamsters inoculated with osteosarcoma, Os515, in the right hind limb were studied 7 days after inoculation. One day prior to the animal study, either a permanent magnet (with magnetic force) or non-magnetic alloy (without magnetic force) was implanted in the center of the tumors. Treatment with magnetic ADR liposomes under magnetic force showed significantly greater antitumor activity than intravenous administration of ADR solution or that of magnetic ADR liposomes without magnetic force. ADR administered as magnetic liposomes eliminated weight loss of hamsters, one of the side effects produced by ADR. Interestingly, magnetic liposomes (without incorporated ADR) given under magnetic force also suppressed the tumor growth. The selective accumulation of magnetite particles in the tumor blood vessels was observed by histological examination. These results suggest that this systemic chemotherapy can effectively control the primary tumor without significant side effects, due to the targeting of magnetic ADR liposomes.

Animals↗

PubMed2001

Galectin-3 maintains the transformed phenotype of thyroid papillary carcinoma cells.

Galectin-3, a beta-galactoside-binding protein, is highly expressed in thyroid papillary carcinomas, while functional relevance of galectin-3 overexpression to the malignant phenotype remains elusive. In the present study we transfected galectin-3 antisense cDNA into the human thyroid papillary carcinoma cell line NPA which expresses an innately high level of galectin-3, and examined the effect of antisense inhibition of galectin-3 expression on the transformed phenotype. There was no difference in anchorage-dependent growth between the antisense clones and either the control or parental clones. In contrast, anchorage-independent growth and saturation density of the antisense clones were significantly suppressed compared to those of either the control or parental clones. These results demonstrate that overexpression of galectin-3 in thyroid papillary carcinoma cells is necessary for the maintenance of transformed phenotype, and suggest galectin-3 as a potential target for therapeutic interventions in the future.

Antigens, Differentiation↗

PubMed2001

Effect of thermosensitive liposomal doxorubicin with hyperthermia on primary tumor and lung metastases in hamster osteosarcoma.

We evaluated the effect of intravenous thermosensitive liposomal doxorubicin (TL-DOX) together with local hyperthermia on primary tumors in highly metastatic hamster osteosarcoma. This combination resulted in higher DOX concentrations in plasma, primary tumors and lungs than standard DOX under the same conditions. Tumor growth and lung metastasis were also inhibited more by TL-DOX and hyperthermia than by hyperthermia alone, DOX with or without hyperthermia, and TL-DOX without hyperthermia. In addition, gains in hamster body weight were not suppressed. These results suggest that the combination of TL-DOX and hyperthermia can control primary tumors and suppress lung metastasis in hamsters.

Animals↗

PubMed2001

[Effects of steroid therapy on long-term canal prognosis and activity in the daily life of vestibular neuronitis patients].

We studied 28 patients with vestibular neuronitis treated at our hospital between 1997 and 1999. To determine the effects of steroid therapy on long-term canal prognosis and daily activity, we examined caloric tests and gave questionnaires to 12 steroid-treated and 16 nonsteroid-treated patients 2 years after onset. We found that canal improvement was 50% in the nonsteroid-treated group and 75% in the steroid-treated one. In cases with severe canal paresis (CP > or = 60%), canal improvement was 33% in the nonsteroid-treated group and 67% in the steroid-treated one. Steroid therapy at the acute stage of this disease significantly reduced the duration of spontaneous nystagmus and handicap in daily life due to dizziness induced by head and body movement, decreasing mood disturbance.

Activities of Daily Living↗

PubMed2001

[Changes in otoacoustic emission during the glycerol test in the ears of patients with Meniere's disease].

Monitoring of cochlear function is one proposed clinical application of otoacoustic emission (OAE). To determine the clinical utility of OAE in monitoring, we studied changes in OAE during the glycerol test used to diagnose endolymphatic hydrops. Transiently evoked OAE (TEOAE) and distortion product OAE (DPOAE) were measured before and 3 hours after oral administration of glycerol in 22 ears of patients with Meniere's disease. The positive result in the glycerol test was observed in 11 of 22 ears. TEOAE was recorded using a nonlinear click stimulus, and total echo power (TEP) of the whole response and filtered echo power (FEP) of its mid-frequency (1000-2000 Hz) component were used as TEOAE parameters. The growth functions of DPOAE were recorded at 3 F2 frequencies--1000, 1500, and 2000 Hz. Changes in the growth function were determined based on changes in 2 parameters--maximum level and detection threshold of DPOAE. When changes in these 4 parameters exceeded 2 standard deviations above mean test-retest variability determined from OAE data for 17 normal ears, they were considered significant. Significant changes indicating improved cochlear function in 4 OAE parameters or the appearance of OAE during the glycerol test were judged positive for OAE. Regardless of glycerol test results, positive findings were observed in both OAEs whenever a pure-tone threshold at 1000 or 2000 Hz improved. However, even in ears for which pure-tone thresholds at these frequencies did not improve, both OAEs frequently exhibited positive findings. In all ears with a positive result in the glycerol test, positive findings were observed in DPOAE, but not in TEOAE. Of the 2 parameters of TEOAE, FEP always exhibited a positive finding in ears with a positive TEP finding and FEP positivity was higher than that of TEP. In DPOAE, no cases showed a positive finding only at F2 = 2000 Hz, and DPOAE at F2 = 1000 Hz could not be detected in 4 ears due to high noise floor. Overall, positive findings were obtained in 14 ears (63.9%) for TEOAE and 20 ears (90.9%) for DPOAE. In only 1 ear were no positive findings observed in either OAE. The sensitivity of OAE measurement as a diagnostic test for endolymphatic hydrops was higher than that of pure-tone audiometry. Of the 2 OAEs, test sensitivity was much higher for DPOAE than for TEOAE. These results show that OAE measurement detects changes in cochlear function during the glycerol test more sensitively than pure-tone audiometry. They also suggest that FEP is a better indicator than TEP as a parameter of TEOAE, and that DPOAE measurement at F2 = 1000 and 1500 Hz is sufficient for practical clinical use. However, of the 2 OAEs, DPOAE was considered more appropriate than TEOAE for monitoring during the glycerol test because of its high sensitivity in detection of changes in cochlear function. In conclusion, clinical use of OAE, especially DPOAE, as a test complementary to pure-tone audiometry during the glycerol test is very useful and will improve the diagnosis of endolymphatic hydrops.

Adult↗

PubMed2001

[Endolymphatic sac drainage and steroid-instillation surgery (EDSS) for intractable Meniere's disease].

Endolymphatic sac surgery is one of the most widely accepted techniques used to treat intractable Meniere's disease. To improve this surgery, we developed the following techniques: A simple mastoidectomy was used to expose the endolymphatic sac between the sigmoid sinus and inferior margin of the posterior semicircular canal. The sac was opened and filled with a mass of prednisolone. A bundle of absorbable gelatin films was then inserted into the sac lumen to expand it, followed by gelatin sponges dipped in a high concentration of dexamethasone. Long-term results (17-32 months) in 20 patients with intractable Meniere's disease treated with endolymphatic sac drainage and steroid-insertion surgery (EDSS) showed that definitive spells were completely controlled in 15 of 20 cases (75%); all reports of vertigo decreased; hearing improved in 12 of 20 cases (60%); and annoyance due to tinnitus decreased in 15 of 20 cases (75%). Steroids directly instilled into the endolymphatic cavity may thus be more effective with the diseased inner ear organs than those applied via any other route. Draining of endolymphatic fluid at the sac into the mastoid cavity also contributed to these satisfactory EDSS results.

Adult↗

PubMed2001

Expression of transduced HSP70 gene protects chondrocytes from stress.

OBJECTIVE: To investigate the efficacy of adenovirus vector mediated transduction of heat shock protein 70 (HSP70) gene to human chondrocyte-like cell (HCS-2/8) against heat stress. METHODS: Two adenovirus vectors that contain wild-type (AxSHEwt) or mutant-type (AxSHEmt) HSP70 gene, and that are regulated by SRalpha promoter, were constructed. The mutant-type lacks the area that expresses stress durability. One of the 2 adenovirus vectors was added to the cultures of human chondrocyte-like cells (HCS-2/8). Heat stress (48 degrees C) was applied to the transduced cells for 2 h, and the efficacy of adenovirus vector mediated transduction of HSP70 gene against heat stress in the chondrocytes was investigated using alamar blue assay and MTT assay. RESULTS: Absorbance levels at 48 degrees C were 300.3 +/- 51.9 and 1.173 +/- 0.011 in the controls, 278.5 + 33.8 and 1.217 +/- 0.018 in the AxSHEmt transduced cells, and 349 +/- 14.7 and 1.371 +/- 0.033 in the AxSHEwt transduced cells. The level in the AxSHEwt transduced cells was significantly higher than in the other 2 groups (p < 0.05). With 37 degrees C treatment, no significant difference was observed. CONCLUSION: Chondrocytes to which HSP70 gene was transduced had a significantly higher metabolic activity and viability under heat stress.

Adenoviridae↗

PubMed2001

[Estimation of size of the uncuffed endotracheal tube for pediatric cardiac anesthesia--Cole's formula cannot estimate the appropriate tube size].

We evaluated the validity of Cole's formula (tube size = 0.25 x age + 4) for the estimation of uncuffed endotracheal tube size, and devised new formula with a statistical method on the basis of the ages of 217 pediatric patients with congenital heart disease. The sizes of the tubes actually used for these patients were 0.5 mm or larger than those estimated by Cole's formula in 29% of patients with congenital heart disease. Only one patient with cyanotic heart disease required a tube that was more than 0.5 mm smaller than that estimated by Cole's formula. The regression formula representing the relationship between the tube size and age was "tube size = 0.316 x age + 4.135". In conclusion, tube size estimated by Cole's formula tends to be smaller than practically appropriate tube size for pediatric cardiac anesthesia, and therefore we suggest new formula to estimate the tube size.

Age Factors↗

PubMed2001

Epithelial-mesenchymal interactions in wounds: treatment of palmoplantar wounds by nonpalmoplantar pure epidermal sheet grafts.

BACKGROUND: Palms and soles differ from other body sites in terms of clinical and histologic appearance and response to mechanical stress. We previously reported that palmoplantar fibroblasts regulate keratin 9, which is a marker of palms and soles. OBJECTIVE: To treat palmoplantar wounds by using nonpalmoplantar pure epidermal sheets as a graft. DESIGN: Nonrandomized controlled trials. SETTING: University dermatology and plastic surgery services. PATIENTS: Forty-eight patients with palmoplantar wounds caused by burns, trauma, chronic ulcers, and the resection of malignant tumors, such as squamous cell carcinoma and acral lentiginous melanoma. INTERVENTIONS: The patients received nonpalmoplantar pure epidermal sheet grafts (n = 14), nonpalmoplantar donor site skin grafts (n = 17), or palmoplantar donor site skin grafts (n = 17). MAIN OUTCOME MEASURES: Clinical and histologic findings. RESULTS: The pure epidermal sheets were successfully grafted and gradually demonstrated the adoption of a palmoplantar phenotype when reticular dermis of the recipient site remained. The epidermis showed hyperkeratosis and acanthosis by histologic studies and stained positively for keratin 9 in all of the suprabasal keratinocyte layers like palmoplantar-type skin. Pure epidermal sheets were placed on deeper wounds after the wounds had an artificial dermis applied and adopted the palmoplantar phenotype without erosions and ulcerations. Neither nonpalmoplantar split-thickness nor full-thickness skin grafts resulted in a palmoplantar phenotype. CONCLUSIONS: Pure epidermal sheet grafting would be useful for the treatment of palmoplantar wounds as nonpalmoplantar epidermis is much easier to obtain clinically. In addition, secondary procedures are not required to repair the donor site, since this wound is superficial.

Adolescent↗

PubMed2001

[Clinical significance of measuring inferior vena cava dimension in patients with acute exacerbation of chronic heart failure].

OBJECTIVES: This study determined the clinical significance of measuring the inferior vena cava dimension in patients with heart failure. METHODS: The subjects were 373 patients admitted due to acute exacerbation of chronic heart failure. The relationships were examined between inferior vena cava dimension in the end-expiratory phase on admission and in the stable state and etiology of heart failure, age, New York Heart Association (NYHA) functional classification in the stable state (before exacerbation), body weight, grade of tricuspid regurgitation, left ventricular end-diastolic dimension and left ventricular ejection fraction measured by two-dimensional echocardiography in the stable state and on admission, severity of lung congestion (Killip's classification) on admission, and clinical course during treatment. RESULTS: The inferior vena cava dimension was not correlated with etiology, age, NYHA functional classification, body weight, left ventricular end-diastolic dimension or left ventricular ejection fraction, but was correlated with the grade of tricuspid regurgitation (r = 0.78, p < 0.0001 in the stable state, r = 0.60, p < 0.0001 and on admission). The severity of lung congestion did not correlate with inferior vena cava dimension on admission or the increase in inferior vena cava dimension. The increase in body weight on admission was correlated with the increase in inferior vena cava dimension (r = 0.83, p < 0.0001), but did not correlate with inferior vena cava dimension on admission. Tricuspid regurgitation grade and inferior vena cava dimension were restored to the stable state when body weight reached stable state after treatment in patients (n = 202) with inferior vena cava dimension increased by over 5 mm on admission. CONCLUSIONS: Inferior vena cava dimension in patients with heart failure is correlated with the tricuspid regurgitation grade in the stable state and at acute exacerbation. The increase in inferior vena cava dimension between stable and exacerbated states, but not the actual value, is clinically useful to evaluate patients with acute exacerbation of chronic heart failure.

Chronic Disease↗

PubMed2001

Characteristic features of the acetabular labrum in healthy children.

Radial magnetic resonance images of the acetabular labrum were obtained on 40 hips of healthy children. There were no right-left or male-female differences. In children aged 11 years or younger, the labrum on the antero-superior weightbearing portion was triangular in shape, and there was an insular-shaped or linear high-intensity area inside; on the mid-superior portion, the labrum appeared as a regular triangular, low-intensity area; and on the postero-superior portion, it was flat. In children aged 12 and 13 years, the shape of the labrum in each portion was similar to that of the younger children, but the high signal intensity area on the antero-superior portion appeared less frequently. The size of the labrum relative to the femoral head was greater in younger children.

Acetabulum↗

PubMed2001

Tracer accumulation in femoral head during early phase of bone scintigraphy after renal transplantation.

UNLABELLED: Nontraumatic osteonecrosis of the femoral head (ONF) is a complication of renal transplantation. The pathogenic mechanism of ONF is thought to be an ischemic event. The purpose of this study was to investigate whether 3-phase bone scintigraphy can reveal early hemodynamic changes associated with ONF after renal transplantation. METHODS: We performed 3-phase bone scintigraphy on 19 renal allograft recipients between 3 and 9 wk after they underwent renal transplantation. Regions of interest (ROI) were assigned bilaterally in the femoral heads, diaphyses, and soft tissue. The head-to-diaphysis ratio (HD) in each phase was then calculated. RESULTS: ONF occurred in 8 femoral heads of 4 patients. Three of the 4 ONF patients had no abnormal MRI findings at the time of bone scintigraphy. In phase 1, no significant difference in HDs was observed between the ONF patients (mean HD +/- SD, 0.62 +/- 0.44) and the non-ONF patients (0.31 +/- 1.40). The difference between the mean counts for bone and soft tissue was small in both instances, and the HD had a large dispersion. In phase 2, the HDs for the ONF patients (0.70 +/- 0.27) and the non-ONF patients (1.31 +/- 0.43) were significantly different (P = 0.0005). The HD was <1.00 in all femoral heads of the ONF patients, whereas 9 non-ONF heads had an HD that was <1.00. In phase 3, the HD of the ONF patients was significantly lower than that of the non-ONF patients (ONF patients, 0.92 +/- 0.17; non-ONF patients, 1.62 +/- 0.46; P = 0.0002). CONCLUSION: All ONF patients were in the group with a low HD in phase 2, suggesting a reduction in blood flow or blood pool. Phase 2 accumulation in 3-phase bone scintigraphy can be used to estimate early hemodynamic changes in patients with ONF after renal transplantation.

Adult↗

PubMed2001

Sludge reduction potential of metazoa in membrane bioreactors.

In order to check the sludge reduction capacity of metazoa in a membrane bioreactor (MBR), pilot-scale studies were conducted. Three MBRs had been set in a wastewater treatment plant at Tokyo, Japan and they were receiving real wastewater. Initially pH inside the three MBRs was controlled as pH 7, 6 and 5 respectively. Then metazoa population was monitored along with MLSS change. It was found that the presence or absence of the metazoa population did not have any significant effect on the increasing pattern of MLSS. In the MBR with pH 6 highest accumulation of sludge was observed though a high and steady level of metazoa (1,000-2,000 per ml) was present there. But in this MBR a lot of metazoa attached in the membrane was also observed and here the increase in transmembrane pressure was less than in the other two. So, metazoa population especially the attached one in the membrane plays an effective role in fouling control of the membrane. Presence of attached media may provide a suitable niche for metazoa in the process. So, attached media known as DB lace was also inserted in MBRs for testing its capacity along with inoculum of oligochaete worms. Accumulation of sludge was not satisfactory in the attached string and it seems that inoculated worm could not adjust to the environment as they were not sludge originated. So, in the next experimental stage, attached media was inserted in the form of a bundle and this time no inoculation of worm was used. A steady metazoa population was observed in the system but the accumulation of sludge in the attached media was the same as before.

Animals↗

PubMed2001

A formula based on body length for determining the size of an uncuffed endotracheal tube for pediatric cardiac anesthesia.

Three hundred and thirty-four pediatric patients less than 4 years old who underwent surgery for congenital heart disease were retrospectively studied to devise a practical formula for predicting the appropriate size for an uncuffed endotracheal tube for pediatric cardiac anesthesia. Furthermore, this formula was compared with that for non-cardiac anesthesia obtained from 409 patients without congenital heart disease. A simple regression equation between tube size and body length resulted in the simple predictive formula: "tube size = 0.04 x body length + 1.6" for pediatric cardiac anesthesia. This formula had the same slope and an approximately 0.3 mm larger intercept on the Y-axis compared with that for pediatric non-cardiac anesthesia. Therefore, a one-size larger endotracheal tube is more suitable for use in pediatric cardiac anesthesia than in pediatric non-cardiac anesthesia for the same body length.

Anesthesia↗

PubMed2000

Loss of heterozygosity on 10q23.3 and mutation of the tumor suppressor gene PTEN in benign endometrial cyst of the ovary: possible sequence progression from benign endometrial cyst to endometrioid carcinoma and clear cell carcinoma of the ovary.

Loss of heterozygosity (LOH) at locus 10q23.3 and mutation of the PTEN tumor suppressor gene occur frequently in both endometrial carcinoma and ovarian endometrioid carcinoma. To investigate the potential role of the PTEN gene in the carcinogenesis of ovarian endometrioid carcinoma and its related subtype, clear cell carcinoma, we examined 20 ovarian endometrioid carcinomas, 24 clear cell carcinomas, and 34 solitary endometrial cysts of the ovary for LOH at 10q23.3 and point mutations within the entire coding region of the PTEN gene. LOH was found in 8 of 19 ovarian endometrioid carcinomas (42.1%), 6 of 22 clear cell carcinomas (27.3%), and 13 of 23 solitary endometrial cysts (56.5%). In 5 endometrioid carcinomas synchronous with endometriosis, 3 cases displayed LOH events common to both the carcinoma and the endometriosis, 1 displayed an LOH event in only the carcinoma, and 1 displayed no LOH events in either lesion. In 7 clear cell carcinomas synchronous with endometriosis, 3 displayed LOH events common to both the carcinoma and the endometriosis, 1 displayed an LOH event in only the carcinoma, and 3 displayed no LOH events in either lesion. In no cases were there LOH events in the endometriosis only. Somatic mutations in the PTEN gene were identified in 4 of 20 ovarian endometrioid carcinomas (20.0%), 2 of 24 clear cell carcinomas (8.3%), and 7 of 34 solitary endometrial cysts (20.6%). These results indicate that inactivation of the PTEN tumor suppressor gene is an early event in the development of ovarian endometrioid carcinoma and clear cell carcinoma of the ovary.

Adenocarcinoma, Clear Cell↗