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T Kojima

Publications and source records attributed to T Kojima.

At least 469 records · Page 26Linked to original sources

Effects of several 5-HT1A agonists on hippocampal rhythmical slow activity in unanesthetized rats.

We examined the effect of 5-hydroxytryptamine (5-HT)1A agonists on walking related, atropine-resistant, rhythmical slow activity (wr-RSA) of the hippocampus in rats. Selective 5-HT1A agonists, 8-hydroxy-2-(di-n-propylamino)tetralin (8-OH-DPAT), flesinoxan, buspirone and ipsapirone significantly decreased the power value of 7-9 Hz band activity and the median frequency of wr-RSA. The order of potency was 8-OH-DPAT > flesinoxan = buspirone in power reduction. The 5-HT1A antagonists, (-)pindolol, (-)propranolol and spiperone, inhibited the effect of 8-OH-DPAT on wr-RSA. Pretreatment with parachlorophenylalanine did not abolish the effect of 8-OH-DPAT. These results indicate that 5-HT1A agonists reduce both power and median frequency values of wr-RSA through activation of post-synaptic 5-HT1A receptors in the forebrain in unanesthetized rats, in vivo.

8-Hydroxy-2-(di-n-propylamino)tetralin↗

Cubital tunnel syndrome caused by abnormal insertion of triceps brachii muscle.

Some cases of cubital tunnel syndrome are caused by anatomical abnormalities such as the epitrochleo-anconeus muscle or snapping and bulkiness of the medial head of the triceps brachii muscle. We report a rare cause of cubital tunnel syndrome that has not been reported previously. It was caused by an abnormal insertion of the medial head of the triceps muscle into the medial epicondyle. The clinical course and operative findings are described.

Adult↗

Dynamic relationships between sleep spindles and delta waves during a NREM period.

All-night sleep EEGs from 7 normal young male adults were analyzed by a waveform recognition method using FFT-IFFT band pass filters. The total durations of sleep spindles and sleep delta waves in each 20-s epoch were measured and plotted on an X-Y graph with lines connecting the points in time sequence (dynamic two-component plot). The relationship between these two measures within a single NREM period showed three dynamic phases and one stationary period. In the first phase, spindles increased while delta remained at low level or increased slightly. In the second phase delta increased greatly while spindles decreased. In the third phase, delta decreased while spindles remained at a low level. There was a stationary period between the second and third phases, when delta maintained a higher level and spindles maintained a lower level. These dynamic descriptions reflect the underlying physiological mechanisms more directly than static sleep stages. They should also permit finer analyses of sleep in psychiatric and neurological disorders.

Adult↗

Use of the double-layered free temporal fascia flap for upper extremity coverage.

Two layers of fascia exist in the temporal region, the temporoparietal fascia and the deep temporal fascia. Both can be elevated on a single vascular pedicle based on the superficial temporal artery, the double-layered temporal fascia flap. In our study, six patients who underwent upper limb coverage using the double-layered temporal fascia flap are reviewed, and the versatility of this thin flap is discussed.

Adult↗

The route of administration influences the effect of estrogen on insulin sensitivity in postmenopausal women.

OBJECTIVE: To determine the effect of transdermal estrogen on insulin sensitivity in postmenopausal women and to compare this effect with changes observed with oral conjugated equine estrogens. DESIGN: Fourteen postmenopausal women were randomized to receive a transdermal E2 patch, 0.1 mg, for 25 days each month (n = 7) or transdermal E2 with added medroxyprogesterone acetate (MPA), 10 mg, from days 16 to 25 each month (n = 7). An insulin tolerance test (ITT) was performed at baseline and between days 23 and 25 during the 2nd month of treatment to assess insulin sensitivity. Values for the disappearance of glucose (K(itt)) were calculated and compared with values obtained from women receiving 1.25 mg of oral equine estrogens (n = 8). SETTING: University Clinical Research Center. PATIENTS: Healthy postmenopausal women not receiving hormonal replacement. INTERVENTION: Insulin tolerance tests before and after treatment. MAIN OUTCOME MEASURE: Disappearance of glucose and insulin (K(itt)) before and after treatment. RESULTS: Women receiving transdermal E2 alone demonstrated improved insulin sensitivity. The K(itt) glucose values increased by 13.2%, compared with a 23.9% decrease in K(itt) values observed with 1.25 mg of conjugated equine estrogen. The group treated with transdermal E2 and MPA had a reduction in insulin sensitivity. Insulin clearance was enhanced only with transdermal estrogen and was significantly delayed (blunted clearance) with the addition of MPA to transdermal E2 and with oral estrogen. CONCLUSION: We previously demonstrated a bimodal effect of oral equine estrogens on insulin sensitivity with an improvement occurring with the lower dose of 0.625 mg but with a deterioration with the dose of 1.25 mg. Here we suggest that this effect may be related to a first-pass hepatic-portal effect in that transdermal E2 (0.1 mg), which may be equated more closely with the larger dose of oral estrogen (1.25 mg), improved insulin sensitivity. Progestin, however, appeared to attenuate the beneficial effects of transdermal estrogen and may alter the clearance of insulin.

Administration, Cutaneous↗

Spiral oblique retinacular ligament (SORL) mallet correction in a finger with a proximal interphalangeal joint transferred from a toe.

The use of a spiral oblique retinacular ligament (SORL) reconstruction is reported in a middle finger that had previously undergone reconstruction of the proximal interphalangeal (PIP) joint, using a free, vascularized, second-toe PIP joint transfer. The SORL procedure was applied for the reconstruction of the terminal tendon. A satisfactory postoperative range of joint mobility and stability was achieved.

Adult↗

Chemoprevention of mouse urinary bladder carcinogenesis by the naturally occurring carotenoid astaxanthin.

The chemopreventive effects of two xanthophylls, astaxanthin (AX) and canthaxanthin (CX), on urinary bladder carcinogenesis induced by N-butyl-N(4-hydroxybutyl)nitrosamine (OH-BBN) was investigated in male ICR mice. Mice were given 250 p.p.m. OH-BBN in drinking water for 20 weeks and after a 1 week interval with tap water, water containing AX or CX at a concentration of 50 p.p.m. was administered during subsequent 20 weeks. Other groups of mice were treated with AX or CX alone or untreated. At the end of the study (week 41), the incidences of preneoplastic lesions and neoplasms in the bladder of mice treated with OH-BBN and AX or CX were smaller than those of mice given OH-BBN. In particular, AX administration after OH-BBN exposure significantly reduced the incidence of bladder cancer (transitional cell carcinoma) (P < 0.003). However, the inhibition of the frequencies of such lesions in mice treated with OH-BBN and CX was not significant. Treatment with AX or CX also decreased the number/nucleus of silver-stained nucleolar organizer region proteins (AgNORs), a new index of cell proliferation, in the transitional epithelium exposed to OH-BBN. Preneoplasms and neoplasms induced by OH-BBN, and the antiproliferative potential, was greater for AX than CX. These results indicate that AX is a possible chemopreventive agent for bladder carcinogenesis and such an effect of AX may be partly due to suppression of cell proliferation.

Animals↗

Production of chimeric pigs and the analysis of chimerism using mitochondrial deoxyribonucleic acid as a cell marker.

Two injection methods were examined for making chimeras between Chinese pigs (Meishan) and European pigs (Landrace or Landrace x Large White). Furthermore, mitochondrial DNA (mtDNA) polymorphism was detected as a cell marker for the analysis of chimerism. In the first experiment, blastomeres were transplanted into embryos at the 4-16-cell stage. Of 41 transplanted embryos transferred into 3 females, 12 were single-colored, but no overt chimeras were obtained. Judging from coat color and mtDNA in white blood cells, 2 piglets in 2 litters were derived from injected blastomeres, and 10 piglets in 3 litters were derived from recipient blastomeres. In the second experiment, inner cell mass cells of Day 6 Landrace embryos were injected into blastocoels of Day 6 Meishan embryos. Of 35 injected embryos transferred into 3 females, 2 overt chimeras of each sex were obtained in a single litter. In the overt male chimera, mtDNA clearly showed chimerism in spleen, pancreas, brain, kidney, lung, liver, heart, testis, and small intestine. The overt female chimera showed chimerism not only in blood but also in germ line according to a progeny test. No chimerism was detected in any of the 21 single-colored piglets in the second experiment.

Animals↗

Ethanol injection sclerotherapy for Baker's cyst, thyroglossal duct cyst, and branchial cleft cyst.

Six patients with Baker's cysts, 3 with branchial cleft cysts, and 2 with thyroglossal duct cysts were treated with percutaneous aspiration and absolute ethanol sclerotherapy using a 7-French pigtail catheter. Cystography was performed before ethanol injection to confirm that there was no extravasation and that it was a monocystic lesion. One recurrence of a Baker's cyst was revealed in follow-up examinations, which ranged from 11 months to 36 months (mean, 25 months). The major complication of hypoesthesia of the popliteal region was observed in 1 patient treated for Baker's cyst. The results of this series suggest that ethanol sclerotherapy is the treatment of choice for Baker's cyst, branchial cleft cyst, and thyroglossal duct cyst.

Adolescent↗

Nasal reconstruction using free temporoparietal fascial flap transfer (Upton's method).

Reconstructive surgery for severe nasal deformity after radical operation of the maxillary antrum was performed by free temporoparietal fascia transfer to the nasal membrane, followed by secondary-rib cartilage grafting. Correction of nasal deformity caused by severe scar contracture and tissue defect in the nasal cavity has been considered difficult. However, skin grafting with temporoparietal fascia transfer to the nasal membrane can make it possible to perform cartilage grafting without exposure. This method should be nominated as a useful procedure for correction of severe nasal deformity caused by nasal membranous scar contracture.

Female↗

Suppression of azoxymethane-induced rat colon aberrant crypt foci by dietary protocatechuic acid.

The modifying effect of dietary exposure to protocatechuic acid (PCA) on the development of azoxymethane (AOM)-induced colonic aberrant crypt foci (ACF) was investigated in male F344 rats. The effects of PCA feeding on the silver-stained nucleolar organizer regions protein (AgNORs) count in the colonic epithelial cells and on the ornithine decarboxylase (ODC) activity in the colonic mucosa were also estimated. Animals were given weekly s.c. injections of AOM (15 mg/kg body weight) for 3 weeks to induce ACF. These rats were fed diet containing 1000 or 2000 ppm PCA for 5 weeks, starting one week before the first dosing of AOM. All rats were killed 2 weeks after the last AOM injection, to measure the number of ACF, ODC activity, and AgNORs count per nucleus in the colon. In rats given AOM and PCA, the frequency of ACF/colon was significantly decreased compared with that in rats given AOM alone (P < 0.005 at 1000 and P < 0.05 at 2000 ppm). ODC activity in the colon of rats given AOM and PCA at both doses was also significantly lower than that of rats treated with AOM alone (P < 0.05). Similarly, the mean AgNORs count in rats fed PCA was significantly smaller than that of rats treated with AOM alone (P < 0.0001). Treatment with PCA alone did not affect these three biomarkers. These results provide further evidence that PCA could be a chemopreventive agent against rat colon carcinogenesis.

Animals↗

Production of endothelin-1 induced by blood transfusion in premature infants.

We demonstrated a relationship between blood transfusion and plasma ET-1 levels in 10 premature infants with anemia. Changes in plasma ET-1 and lipoperoxide levels, blood pressure and available oxygen before and after the blood transfusion were determined. Plasma ET-1 levels were significantly elevated after blood transfusion (before: 8.0 +/- 2.8; after: 15.7 +/- 5.4 pg/ml, p < 0.01). A positive correlation was observed between plasma ET-1 levels and lipoperoxide levels (r = 0.887, p < 0.01). There was a significant correlation between plasma ET-1 levels and transfused blood volumes (r = 0.758, p < 0.01). No positive correlation was observed between plasma ET-1 levels and available oxygen. These results suggest that blood transfusion may be a stimulator of ET-1 overproduction and that it may lead to tissue injury through an endothelin-induced oxygen radical formation system.

Adult↗

Characterization of renal tubular damage in preterm infants with renal failure.

This study attempts to clarify the characteristics of renal tubular damage in preterm infants with renal failure. Sixty-one neonates (17 term and 44 preterm infants) were divided into three groups: 15 infants with intrinsic renal failure (IRF), five term and 10 preterm; 19 with pre-renal renal failure (PRF), five term and 14 preterm; and 27 without renal dysfunction (control), seven term and 20 preterm. Urine was collected for an 8 h period on the 2nd or 3rd day of life to determine the following parameters: creatinine clearance (Ccr), fractional excretion of sodium (FENa), urinary N-acetyl-beta-D-glucosaminidase (NAG) index and endothelin-1 (ET-1) excretion. Parameters of renal tubular function and/or renal tubular damage such as FENa, NAG index and ET-1 excretion were considered as a useful marker to differentiate IRF from PRF in preterm infants. However, these parameters were significantly elevated in preterm infants with PRF. These findings led us to make the following speculations: (i) renal tubular damage may easily occur in preterm infants; and (ii) there still remains difficulty in differentiation between IRF and PRF using Ccr instead of the fluid challenge test.

Acetylglucosaminidase↗

Effects of zopiclone, triazolam, and nitrazepam on standing steadiness.

We examined the effects of the nonbenzodiazepine hypnotic zopiclone and the benzodiazepine hypnotics triazolam and nitrazepam on standing steadiness. Eight healthy volunteers received placebo, zopiclone (7.5 mg), triazolam (0.25 mg), and nitrazepam (5 mg) in a random-order, double-blind crossover design. Postural sway was assessed before and 1 and 2 h after drug administration using a stabilometer connected to a microcomputer. Triazolam significantly impaired standing steadiness. Zopiclone also impaired standing steadiness but the degree of impairment seemed to be less marked. Nitrazepam 5 mg had no significant effects on postural sway. Triazolam 0.25 mg, zopiclone 7.5 mg, and nitrazepam 5 mg, which are reported to be equipotent to each other as hypnotics, are not equipotent with respect to their effects on postural sway.

Adult↗

Clinical significance of diffuse delta EEG activity in chronic schizophrenia.

1) Forty-three chronic schizophrenics with diffuse delta activity (DDA) in their rest-awake EEGs were compared with 23 chronic schizophrenics with normal EEGs. 2) The DDA group was divided into three sub-groups according to the temporal persistence of DDA: brief, intermittent, and prolonged. The intermittent DDA is analogous to intermittent rhythmic delta activity (IRDA). 3) The disorganized type of schizophrenia was frequent in the DDA group and the residual type was frequent in the normal EEG group. 4) The doses of neuroleptics, as well as those of phenothiazines and butyrophenones, were higher in the DDA than in the normal group. 5) The frequency of co-administration of carbamazepine was higher in the DDA than in the normal group, and the rate increased with the degree of abnormality. 6) In a 1 year follow-up of the DDA group, reducing doses of neuroleptics resulted in a tendency for DDA to disappear, and reducing the doses of adjunctive carbamazepine caused DDA to disappear. 7) There was no correlation between DDA and the psychiatric symptoms, intelligence level, or CT findings.

Antipsychotic Agents↗

Surgical treatment of ossification of the posterior longitudinal ligament in the thoracic spine.

Thoracic ossification of the posterior longitudinal ligament (OPLL) is a rare entity causing thoracic myelopathy. Its surgical decompression is still challenging. Three patients admitted with progressive myelopathy due to thoracic OPLL are described. A transthoracic anterolateral approach was used in the first and second cases, in which OPLL was located at the T3-T4 and T5-T6 and at the T7-T8 levels, respectively. In the third case, a transsternal approach was adopted for OPLL at the T1-T2 level. The OPLL, including dural ossification, was removed by microsurgical techniques as extensively as possible. Myelopathy in all three cases became relieved or stable postoperatively. Operative procedures are described in detail. From the viewpoint of surgical anatomy, the selection of operative approach depends on the level of the OPLL. The authors emphasize that a transthoracic anterolateral approach is the treatment of choice for extensive anterior pathology such as OPLL involving more than two thoracic bodies below the T4. A transsternal approach can provide excellent access to a lesion at the upper three thoracic bodies.

Aged↗