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Biomedical subjects

K Kikuchi

Publications and source records attributed to K Kikuchi.

At least 775 records · Page 43Linked to original sources
PubMed1993

Inhibition of placental thyroxine 5-deiodinase activity decreases amniotic fluid concentration of 3,3',5'-triiodothyronine in rat.

We investigated whether the inhibition of placental T4 5-deiodinase (5-D) activity would decrease the amniotic fluid (AF) concentration of rT3. Iopanoic acid (IOP) was used to inhibit placental T4 5-D activity. From gestation days 14 to 17, a group of rats received IOP (10 mg/100 g bw/day, sc) once daily in experiment (exp) 1, and received it (40 mg/100 g bw/day) four times daily in exp 2. In exp 2, control dams received propylthiouracil (PTU; 2 mg/100 g bw/day) instead of IOP. Methimazole and T4 were also given to all dams in exp 1 and 2. On day 17 of gestation, we collected the liver, placenta, blood, and AF of each animal. In the IOP-treated group in both experiments, the serum T4 concentration was significantly increased. Hepatic T4 5'-deiodinase activity was significantly decreased by either PTU or IOP administration. In both experiments placental T4 5-D activity was significantly decreased in the IOP-treated group. The concentration of rT3 in AF was significantly decreased in the IOP-treated group in exp 2 (1.71 vs. 0.75 nmol/l, P < 0.01) despite a higher serum T4 concentration. There was a significant positive correlation between placental T4 5-D activity and the concentration of rT3 in AF in exp 2 (r = 0.62, P < 0.05). These observations indicate that the inhibition of placental T4 5-D activity decreases the concentration of rT3 in rat AF, and that placental T4 5-D and the T4 concentration in maternal serum plays important roles in maintaining the concentration of rT3 in rat AF.

Amniotic Fluid↗
PubMed1993

Usefulness of a simple device to measure aural canal temperature.

In patients with spinal cord injury, rectal temperature is difficult to use as body temperature due to impairment such as defecation disturbance. We developed an earphone type device to measure aural canal temperature that can be also used during exercise in patients with spinal cord injury and evaluated its usefulness. The subjects consisted of 11 healthy male students. They exercised for 30 minutes using an ergometer until the heart rate increased to 150-160 bpm. Aural canal temperature, rectal temperature, and non-contact tympanic membrane temperature were measured before, during, and after exercise. This device for the measurement of aural canal temperature was produced by cutting the tip of a commercially available earphone and connecting a thermocouple wire to it. This device is very small and causes no discomfort even during long wearing or inconvenience during exercise. The aural canal temperature obtained in this study was very stable compared with the rectal temperature or non-contact tympanic membrane temperature and thus may be useful for monitoring body temperature.

Adolescent↗
PubMed1993

Effect of chronic hypoxia on oxidative enzyme activity in rat skeletal muscle.

To determine the effects of chronic hypoxia on oxidative capacity in skeletal muscle, 10-week-old Wistar male rats were exposed continuously to normobaric hypoxia (10% O2) for 4 weeks. To unify the level of activity in skeletal muscle of the lower limbs, some rats were treated by surgical sciatic denervation. After the experimental period, rats were anesthetized and their plantaris and soleus muscles were removed. Muscle samples were homogenized and analyzed for the mitochondrial enzymes malate dehydrogenase (MDH) and 3-hydroxyacyl-CoA dehydrogenase (HAD) activities by spectrophotometer. Sciatic denervation caused a decrease in MDH and HAD activities in both the plantaris and the soleus. Hypoxia also reduced MDH activity in the denervated plantaris muscle. As the ATP demands in the plantaris of hypoxic rats might be equal to that of normoxic rats, the reduction of MDH levels by hypoxia was not caused by a decreased level of muscle activity during hypoxic exposure. Our results indicate that chronic hypoxia has a negative effect on the oxidative enzyme MDH activity in rat skeletal muscle.

3-Hydroxyacyl CoA Dehydrogenases↗
PubMed1993

Gender difference in the relationship between physical fitness and mental health.

The purpose of this study was to examine the relationship between physical fitness and mental health in men and women. Twenty-five students (12 men and 13 women) aged 19 to 23 years participated in this study as subjects with low life stress who did not participate in competitive sports. Their physical fitness level was determined according to VO2max test results obtained using a cycle ergometer, and their mental health status according to the results of psychological measurement using the Profile of Mood States (POMS) and Spielberger's State-Trait Anxiety Inventory (STAI). In the men, there was significant correlation of VO2max with each of the POMS subscores for tension (r = -0.61), depression (r = -0.61), fatigue (r = -0.60), and total mood disturbance (r = -0.59), as well as with STAI state (r = -0.66) and trait (r = -0.76) anxiety scores. On the other hand, no similar correlation was found in the women. These results suggest that the relationship between physical fitness and mental health in men differs from that in women.

Adult↗
PubMed1993

Alterations of insulin content and insulin binding to plasma membranes in rat brown adipose tissue during cold exposure and cold acclimation.

We examined the insulin content, insulin binding to plasma membranes, and in vitro oxygen consumption of brown adipose tissue (BAT) from warm-acclimated (25 degrees C), acute cold-exposed (5 degrees C, 24 h: CE), and cold-acclimated (5 degrees C, 4 weeks: CA) rats. Plasma insulin level was significantly lower in CE rats, but it did not differ between CA rats and warm controls. Insulin content per mg BAT weight from CE and CA rats were about three-times higher than those from controls. 125I-insulin binding to plasma membranes of BAT from CE rats was higher and that from CA rats was lower than that from respective warm controls. Scatchard plots analysis showed that the number of insulin binding sites per mg protein of BAT plasma membranes from CE rats increased by 100%, while that from CA rats decreased by 35% without any changes of affinity constant. Basal oxygen consumption of BAT from CE rats was higher than warm controls, and suppressed by insulin. Insulin did not affect basal oxygen consumption of BAT from CA and warm control rats. Noradrenaline-induced oxygen consumption of BAT from warm controls and CE rats was suppressed by insulin. These findings suggested that insulin was involved in the regulation of BAT thermogenesis by changing insulin status in BAT (content and binding to plasma membranes) during cold exposure and cold acclimation.

Acclimatization↗
PubMed1993

Roles of embryonic astrocytes and Schwann cells in regeneration of adult rat dorsal root axons: qualitative observations.

Transplants of fetal spinal cord support regeneration of severed dorsal root axons and allow synapse formation. To analyze the components of the transplants that provide this favorable environment, we studied whether or not 1) the embryonic spinal cord transplants contain Schwann cells, a major producer of laminin, and 2) whether dorsal roots regenerate into transplants of immature astrocytes. We used calcitonin gene-related peptide (CGRP), laminin and glial fibrillary acidic protein (GFAP) immunocytochemistry to identify regenerated axons, Schwann cells and astrocytes, respectively. CGRP-immunoreactive axons regenerated into embryonic day 14 fetal spinal cord transplants, but the transplant did not contain laminin. Dorsal roots immunoreactive for CGRP also regenerated into suspensions of cultured astrocytes. The transplanted astrocytes also favored the expression of laminin and GFAP. CGRP-labeled axons regenerated and distributed widely into the polycarbonate tubes coated with poly L-lysine and containing medium with or without cultured astrocytes. These results indicate that Schwann cells are not likely to account for dorsal root regeneration into transplants of fetal spinal cord and that astrocytes may in fact induce regeneration. Regeneration may also take place in response to various environments.

Animals↗
PubMed1993

Bilateral vertebral artery occlusion secondary to atlantoaxial dislocation with os odontoideum: implication for prophylactic cervical stabilization by fusion--case report.

A 27-year-old male presented with an unusual atlantoaxial dislocation associated with os odontoideum, after suffering sudden onset of significant neurological deterioration. Angiography demonstrated simultaneous occlusion of the bilateral vertebral arteries assumed responsible for the devastating neurological deficits. He initially underwent cervical immobilization with a Crutchfield tong for 2 months and subsequent posterior fusion using an iliac bone graft and wires. The neurological symptoms gradually subsided, and 5 years later good healing of the bone graft without instability and ample subarachnoid space around the spinal cord were radiologically confirmed. Early prophylactic stabilization of atlantoaxial dislocation due to os odontoideum is recommended to prevent a poor outcome. Careful angiographic evaluation of the vertebrobasilar circulation is important for management of patients with os odontoideum.

Adult↗
PubMed1993

Pharmacokinetic characterization of menaquinone-4 in dogs by sensitive HPLC determination.

A simple and sensitive assay method for a pharmacokinetic study of Menaquinone-4 in dogs was established using HPLC with fluorescence detection following extraction with organic solvent. The quantification limit of this method was 1 ng/ml of plasma. A new oily solution formulation of Menaquinone-4 was administered orally to nonfasted dogs at doses of 0.4, 4 and 40 mg/kg. The plasma concentrations reached maximum levels at 1 to 1.5 h after dosing, and then decreased slowly. AUC values up to 24 h after administration were almost dose-proportional. Menaquinone-4 was also administered to dogs in soft-capsules, for comparison with a conventional hard-capsule oral formulation and an intravenous lecithin formulation. The mean AUC for oral dosing in the soft-capsule formulation was 13.5% of that for intravenous dosing in lecithin, and was 4.6 times higher than that for oral dosing in hard-capsules. Additional dosing in fasted dogs indicated that the AUC in pre-fed dogs was about 4 times higher, suggesting that feeding before giving Menaquinone-4 raises the bioavailability. Overall Menaquinone-4 was absorbed rapidly after administration in non-fasted dogs and dose-proportional bioavailability was obtained among the doses of 0.4 to 40 mg/kg. Higher plasma concentrations were observed after administration in the soft-capsule formulation rather than in the hard-capsule formulation. These findings suggest that the soft-capsule formulation would show a good pharmacokinetic profile for elderly patients with osteoporosis.

Administration, Oral↗
PubMed1993

[A case report of an ectopic ureter in a patient treated for chronic prostatitis].

A male aged 20 had been treated for anal and lower abdominal pain after ejaculation for about 2 years under the diagnosis of chronic prostatis. Because of worsening of the pain, he was admitted to our hospital in September 24, 1991. On the rectal examination, a cystic tumor was palbable on the left side of the prostate. The left kidney was not detected by IVP and ultrasonography. CT revealed two retrovesical cystic lesions in the left side. Cystourethroscopy showed an absence of ureteral orifice and ureteral ridge on the left side. Left uretero-seminal vesiculectomy was performed on October 3rd, under the diagnosis of an ectopic ureter entering into the seminal vesicle or ejaculatory duct. Histopathologically, the left ectopic ureter entering into the lower portion of the seminal vesicle or ejaculatory duct and the left renal agenesis were diagnosed. It was remarkable that ureteral epithelium was not transitional but columnar epithelium.

Adult↗
PubMed1993

In vitro and in vivo analysis of cellular origin of cervical squamous metaplasia.

We have previously shown that cultured normal human endocervical cells (HENs) form epithelium resembling squamous metaplasia in vivo. To analyze the cellular origin of squamous metaplasia, the cytokeratin and mucin expression and morphological features of HENs in monolayer cultures and in implants beneath the skin of nude mice were examined. Primary HENs had two distinct morphological phenotypes in vitro pleomorphic epithelial cells and keratinocytelike cells. Using a panel of monoclonal antibodies for various cytokeratins (CKs), we observed that the pleomorphic cells, which were the primary outgrowths, expressed CK7 and CK18 and produced mucin, suggesting their origin to be the mucosecretory columnar cells (CCs) of the endocervix. Keratinocytelike cells were observed in proximity of the CC-like cells after a few days of HEN culture. Interestingly, these cells were homogeneously negative for CK7 expression, as for native reserve cells (RCs), and homogeneously positive for CK13 expression with the antibody that is specific for RCs. During early passages, the culture consisted mostly of the RC-like keratinocytelike cells, and in the late passages, the CC-like cells were predominant. HEN implants in nude mice morphologically formed epithelia similar to immature squamous metaplasia and showed variable CK18 expression. Moreover, they showed homogeneous CK13 expression throughout all layers and expressed mucin and CK7 in the suprabasal cells. The possibility that the HEN culture was originally a mixed population of CCs and RCs, that we failed to detect, cannot be eliminated. Our results support the more likely view that the endocervical simple epithelia, which form squamous metaplasia, are bipotential cells and undergo differentiation readily and reversibly to give rise to CC-like and RC-like cells in culture.

Adult↗
PubMed1993

[Two cases with acquired immunodeficiency syndrome in our hospital].

We report two cases of AIDS whom we have recently experienced. One patient was a 54-year-old man who admitted our hospital due to third degree burn. In this case, we did not know whether or not he was suffered from AIDS, when he was delivered by the ambulance. In autopsy, pneumocystis carinii pneumonia and renal tuberculosis were found in addition to marked decrease of T cells in lymph nodes. The other patient was a 40-year-old man with remarkable symptoms of central nervous system. Route of infection of HIV is unknown. He had dementia, left hemiplegia, bulbar palsy, progressed to rigid decorticate posture and died of respiratory arrest due to involvement of the brain stem, despite of treatment including use of 3'-azido-2',3'-dideoxythymidine (AZT). Magnetic resonance (MR) images showed progressive cerebral atrophy and a diffuse high signal intensity area of cerebral white matter on T2-weighted MR images, suggesting the diagnosis of HIV-induced encephalopathy.

Acquired Immunodeficiency Syndrome↗
PubMed1993

Bronchoplastic procedures for tuberculous bronchial stenosis.

Thirty-six patients underwent tracheobronchoplastic procedures for treatment of tuberculous tracheobronchial stenosis. The modes of operations were left upper sleeve lobectomy in 13 patients, sleeve resection of the left main bronchus in 12 patients (two underwent concomitant left upper lobectomy), right upper sleeve lobectomy in five patients, sleeve resection of the right intermediate bronchus in two patients, right sleeve superior segmentectomy of the lower lobe in one patient, sleeve resection of the trachea with concomitant left pneumonectomy in one patient, carinal resection with right upper sleeve lobectomy and middle lobectomy in one patient, and dilatation of the left main bronchus with a free skin graft reinforced with a steel wire in one patient. One patient died of pulmonary edema of unknown cause on the first postoperative day. Anastomotic stenosis occurred in seven patients. One of these patients underwent reoperation and six underwent endoscopic dilatation. One patient died in the hospital of massive bleeding during endoscopic dilatation 4 months after operation. Slight to moderate stenosis resulted in the remaining patients. Although there are some complications, we believe bronchoplastic operation is worthwhile for restoring pulmonary function in patients with tuberculous tracheobronchial stenosis.

Adult↗
PubMed1993

[Multidisciplinary treatment for a patient with recurrent thymoma associated with myasthenia gravis (MG), pure red cell aplasia (PRCA), and hypogammaglobulinemia].

The patient is 62-year-old female. When she was 43 years old, MG occurred. At age of 49 years thymoma was found and complete thymectomy (stage III) and postsurgical irradiation were performed. At age of 57 years pleural dissemination of the thymoma was found. Chemotherapy was effective but did not obtain total tumor cell kill. Though chemotherapy has been repeated for each tumor regrowth, the regimen used at first recurrence became ineffective and the interval between tumor regrowth became shorter. This year, when she is 62 years old, PRCA and hypogammaglobulinemia were accompanied with the forth tumor regrowth.

Agammaglobulinemia↗
PubMed1993

[Gastric metastasis of primary lung cancer].

A 74-year-old man was admitted to Keio University Hospital because of an abnormal shadow in the right upper lung field on chest roentgenogram. Bronchoscopic examination revealed malignant cells, by which large cell carcinoma of the lung was diagnosed. Systemic survey for metastasis disclosed an ulcerated tumor on the greater curvature of the stomach. Endoscopic examination showed an elevated submucosal tumor suggesting submucosal metastasis of lung cancer to the stomach. A review of 473 autopsies of primary lung cancer at Keio University from 1958 to 1987 showed 16 cases with gastric metastasis (3.4%). Two of 16 cases were detected clinically. Gastric metastases were proven in 15.6% of autopsy cases of large cell carcinoma of the lung. Forty-three cases of primary lung cancer with gastric metastasis were reported in the Japanese literature from 1965 to 1990. Thirteen of these cases had large cell carcinoma.

Aged↗