Search PubMed⌕ Search

Biomedical subjects

T Tajima

Publications and source records attributed to T Tajima.

At least 253 records · Page 14Linked to original sources
PubMed1995

Hepatic cytokeratin changes in obstructive jaundice: before and after biliary drainage.

We investigated the changes in hepatic cytokeratins in obstructive jaundice by immunohistochemistry. The results can be summarized as follows: 1) In accordance with the progression of the jaundice, the lobular and cellular distribution of cytokeratin reactivity in hepatocytes expanded. 2) Cytokeratin reactivity in obstructive jaundice was improved by removal of the bile duct obstruction (decompression), but this decompressive effect deteriorated in the case of prolonged jaundice. 3) It is suggested that the specific lobular and cellular distribution and/or the changes in cytokeratin aggregation might be of value in determining the stage and in predicting the prognosis of obstructive jaundice.

Animals↗
PubMed1994

Epithelial Proliferative Lesions and Carcinomas in Fibroadenomas of the Breast.

Sixteen cases of fibroadenomas with epithelial proliferative lesions (EP lesions) with histologic features resembling those of epithelial hyperplasia, sclerosing adenosis, and microglandular adenosis, and four cases of carcinomas in fibroadenomas (CA lesions) were studied histopathologically and immunohistochemically. The CA lesions included one intraductal carcinoma, two invasive ductal carcinomas, and one lobular carcinoma in situ. The histologic features of the EP lesions and CA lesions were fundamentally the same as those of carcinomas commonly observed in the mammary gland. Immunohistochemically, smooth muscle actin was useful in the detection of myoepithelial cells, particularly in EP lesions of the adenosis type (sclerosing adenosis or microglandular adenosis), and in distinguishing carcinoma. The differences between EP lesions and CA lesions of sites of immunoreactivity to CA15-3, CEA, and EMA were also helpful for differential diagnosis.

Journal Article↗
PubMed1994

Adrenocorticotropin and growth hormone secretions after intracerebroventricular administration of neostigmine in rats: their relationships to hypothalamic monoaminergic neuronal activities.

Serum adrenocorticotropic hormone (ACTH) and growth hormone (GH) concentrations were assessed simultaneously with hypothalamic neuronal activities of norepinephrine (NE), dopamine (DA), and serotonin (5-HT) 60 min after the third cerebroventricular administration of neostigmine (a cholinesterase inhibitor) in awake rats. Serum ACTH and GH concentrations were significantly increased and decreased, respectively. Neostigmine caused significant increases in hypothalamic NE and DA activities and a significant decrease in hypothalamic 5-HT activity. The reciprocal changes of serum ACTH and GH concentrations were similar to those of hypothalamic NE and 5-HT activities. Multiple regression analyses with stepwise procedure revealed that hypothalamic NE and 5-HT activities were respectively significant determinants of serum ACTH and GH concentrations. Apart from the direct influence of neostigmine on ACTH and GH secretions, it is suggested that the changes in hypothalamic monoaminergic activities play an important role in modulating ACTH and GH secretions following the administration of neostigmine.

Adrenocorticotropic Hormone↗
PubMed1994

Effect of vitamin K2 (menatetrenone) on osteoclast-like cell formation in mouse bone marrow cultures.

The effects of menatetrenone, a vitamin K2 homologue, on osteoclast-like cell formation in mouse bone marrow culture were investigated. After 7 days of incubation, menatetrenone at 10(-6) M, 3 x 10(-6) M and 10(-5) M dose dependently inhibited the tartrate-resistant acid phosphatase-positive multinucleated cell formation induced by 1,25-dihydroxyvitamin D3 (1,25(OH)2D3). The addition of menatetrenone for the last 3 days of the 7-day incubation period was required to inhibit formation of multinucleated cells in response to 1,25(OH)2D3. Moreover, the addition of 1,25(OH)2D3 for the last 3 days was essential for multinucleated cell formation, and this activity was markedly inhibited by the simultaneous addition of menatetrenone. The inhibitory effects of menatetrenone on multinucleated cell formation may contribute to its ameliorative action on bone loss in vivo, and may indicate a new mechanism of vitamin K2 activity in bone metabolism.

Acid Phosphatase↗
PubMed1994

HLA-DR4 antigen and lymph node metastases in poorly differentiated adenocarcinoma of the stomach.

BACKGROUND: The authors investigated whether HLA antigens could act as a predictor of the risk of lymph node metastasis in patients with gastric cancer. METHODS: The microcytotoxicity assay was used to examine 51 HLA antigens of the A, B, C, DR, and DQ loci in 573 patients who underwent resection of gastric cancer. The incidence of HLA antigens in patients with or without lymph node metastasis was analyzed using the chi-square method. RESULTS: The incidence of patients with HLA-DR4 antigen with or without lymph node metastasis was 45.9% and 34.8%, respectively (P = 0.0098, corrected P = 0.49). The relative risk of lymph node metastasis in patients with HLA-DR4 was 1.6. In poorly differentiated adenocarcinoma, the incidence of HLA-DR4 antigen in patients with lymph node metastasis was significantly higher (47.5%) than in patients without lymph node metastasis (18.5%), if corrected P values were tested (P = 0.0007, corrected P = 0.0387). The relative risk of lymph node metastasis in patients with poorly differentiated adenocarcinoma with DR4 was 4.0. CONCLUSIONS: The data suggest an association between the presence of HLA-DR4 and an increased risk of lymph node metastasis, especially in poorly differentiated adenocarcinoma.

Adenocarcinoma↗
PubMed1994

The strategy to treat disseminated neuroblastoma utilizing bone marrow transplantation: what is the surgeon's role?

The current role of surgery was evaluated in seven consecutive patients with high-risk neuroblastoma (six stage 4 patients and one stage 3, abdominal origin, and all over 12 months of age at diagnosis) treated with new modalities utilizing bone marrow transplantation (BMT). In six of these seven patients, a grossly complete excision of the primary tumor was achieved, and four have survived for 133, 69, 39, and 28 months with no further evidence of disease. The remaining patient with celiac neuroblastoma only underwent a biopsy during a second-look laparotomy after chemoradiotherapy, and thereafter developed local and distant recurrences and ultimately succumbed to the tumor. The timing of surgical intervention varied, either before or after chemotherapy, and did not appear to affect the ultimate survival. Although surgical excision of the primary tumor remains a very high priority in the overall treatment scheme, the most important factor remains the eradication of the tumor by well-planned courses of intensive chemotherapy (e.g., A1 Protocol of the Study Group of Japan). Thus, after having induced complete remission, for consolidation, it is necessary to kill all remaining tumor cells by giving supralethal doses of chemotherapy including total body irradiation (TBI) assisted by BMT.

Adrenal Gland Neoplasms↗
PubMed1994

Hyperbaric oxygen combined with nicardipine administration accelerates neurologic recovery after cerebral ischemia in a canine model.

OBJECTIVE: To evaluate the efficacy of combined therapy--hyperbaric oxygenation with nicardipine administration--for neurologic recovery after complete cerebral ischemia. DESIGN: Randomized, prospective, controlled, unblinded, study, with 14-day postischemic observation. SETTING: Laboratory of the Department of Anesthesiology, Tohoku University School of Medicine. SUBJECTS: Nineteen healthy mongrel dogs (mean weight 10.4 kg) divided randomly into two groups-ten dogs in the untreated group and nine dogs in the treated group. INTERVENTIONS: Fifteen minutes of complete global cerebral ischemia was achieved by occlusion of the ascending aorta and the caval veins. Dogs in the treated group each received a 0.01-mg/kg bolus injection of nicardipine immediately after the reestablishment of circulation, followed by a 0.03-microgram/kg/min continuous infusion of nicardipine for 3 days and hyperbaric oxygen therapy with 3 atmospheres absolute pressures in an FIO2 of 1.0 for 1 hr at 3, 24, and 29 hrs after ischemia. Neurologic recovery was evaluated based on the survival time and rate, the Electroencephalogram (EEG) Score (1 = normal, 5 = isoelectric), and the Neurologic Recovery Score (100 = normal, 0 = brain dead) over a 14-day postischemic period. MEASUREMENTS AND MAIN RESULTS: Neurologic Recovery Scores of the treated group were always higher than those scores of the untreated group throughout the 14-day period. The best Neurologic Recovery Score was 83.1 +/- 5.3 in the treated group and 46.9 +/- 5.2 in the untreated group (p < .01). The numbers of dogs that recovered to a Neurologic Recovery Score of > 85 (assessed as almost normal) was five of nine in the treated group and none of ten in the untreated group (p < .01). Recovery of EEG over 14-day period was better in the treated group. The survival rate and the predicted survival rate were 78% and 13.6 days in the treated group and 30% and 9.0 days in the untreated group, respectively (p < .04 for the survival rate and p < .05 for the survival time). CONCLUSION: Combined therapy, using hyperbaric oxygenation with nicardipine administration, given after 15 mins of complete global cerebral ischemia, accelerates neurologic recovery in dogs.

Animals↗
PubMed1994

Bio-histochemical aspects of integrins (alpha 2 beta 1, alpha 6 beta 1) in invasive mammary carcinomas: an immunohistochemical study.

Immunohistochemical expression of integrins was examined in 39 human invasive mammary carcinomas, of which 34.2% and 43.6% expressed integrins alpha 2 beta 1 and alpha 6 beta 1, respectively. Immuno-electron microscopy clearly demonstrated that the integrins were in the cell membrane of the carcinoma cells. Similar expression of integrin alpha 2 beta 1 or alpha 6 beta 1 in both the intraductal component and invasive portion of the same tumor was seen in 76.9% and 85.7% of cases, respectively. This suggested that invasive carcinoma cells retained their integrin expression after invasion through the basement membrane. Reciprocal expression of integrins alpha 2 beta 1 and alpha 6 beta 1 was seen in 20 cases. Expression of alpha 2 beta 1 was seen significantly less frequently in scirrhous carcinoma than in the more differentiated papillotubular or solid tubular carcinoma (Chi-squared test, P < 0.05). Intraductal components of carcinoma were present more frequently in cases expressing integrin alpha 2 beta 1 than in those that were negative. This suggests the potential usefulness of integrins as clinical parameters in the surgical treatment of mammary carcinoma, since recent trials of conservative treatment for mammary carcinoma have focused on the intraductal spread of the tumor cells.

Antigens, CD↗
PubMed1994

[Detection of group C rotavirus in the day care center].

Group C rotavirus was detected in stools of four patients from February to April, 1993. Of these patients, three were infants who were attendants of the day care center of the hospital. Although the route of viral infection has not been determined, the virus might have been spread within the center. Because the clinical symptoms of acute gastroenteritis caused by group C rotavirus were vomiting, serious anorexia and subsequent difficulty of oral intake of food, patients often required fluid administration therapy at the outpatient clinic. The symptoms continued 1 to 2 days. Diarrhea occurred 1.7 times daily for 1.2 days. Watery stool was found in 3 cases of patients, but no whitish stool was discovered. Vomiting developed 2.2 times daily for 1.2 days. These symptoms were less severe than those of gastroenteritis by group A rotaviral infection. The electrophoretic RNA pattern of group C rotavirus detected in the four cases were the same. However it was different from that of the virus strains previously isolated.

Acute Disease↗
PubMed1994

[Prevalence of penicillin-insensitive Streptococcus pneumoniae and its response to oral beta lactam antibiotics at a primary pediatric office].

Penicillin (PC) resistance of Streptococcus pneumoniae was tested by oxacillin disk method (Bauer-Kirby method) of the strains collected at the primary pediatric office. The rate of oxacillin resistance of S. pneumoniae was 36.4% in 1990, 41.4% in 1991, and 51.9% in 1992, respectively. The efficacy of oral antibiotics in the treatment of PC-insensitive S. pneumoniae infections was also studied retrospectively in 234 cases. Treatment failure rate was 17.7% in the amoxicillin group, 8.7% in the cefpodoxime proxetil group, while it was 42.9% in the cefixime group. These differences were statistically significant. From these data prevalence of PC-insensitive S. pneumoniae is very high in Japanese children, and amoxicillin and cefpodoxime proxetil can be used for the treatment of outpatients with PC-insensitive S. pneumoniae infections.

Administration, Oral↗
PubMed1994

Histologic type and gastric acid secretion in gastric cancer.

We investigated gastric acid secretion in 638 gastric cancer patients with respect to the association between aging and histologic types. In intestinal type tumors in which invasion is restricted to the mucosa, and in diffuse type tumors where the tumor invaded the serosa there was a significantly negative correlation between acid secretion and age. However, no relationship was found between gastric acid output and age in signet ring cell carcinoma. On the other hand, a significantly negative correlation between acid secretion and age was shown in male patients with well differentiated type and in females with signet ring cell carcinoma. In conclusion, low acid secretion related to aging may play an important role in developing cancer cells in intestinal type tumors especially in the male elderly, and in diffuse type tumors in the female elderly, respectively.

Adult↗
PubMed1994

Kinetic analysis of neuromuscular blockade. I. Relationship between twitch depression and stimulation frequency after d-tubocurarine administration.

The degree of twitch depression induced by nondepolarizing neuromuscular blocking drugs is known to be dependent on the stimulation frequency employed. Train-of-four (TOF) stimulations with different frequencies (0.67, 1.33 and 2.0 Hz) were delivered to a sciatic nerve of a rat and series of four twitch heights of a tibialis anterior muscle were measured after d-tubocurarine (d-TC) administration. With a decrease of stimulus interval, twitch heights were intensely depressed. We hypothesized that the oservations are due to the changes of released amount of neuromuscular transmitter, acetylcholine, dependent on stimulus interval, and a pharmacokinetic/pharmacodynamic model based on the hypothesis was proposed. The model allowed simultaneous fitting of the twitch height depression after d-TC administration. It also could give a rationale to the fact that TOF stimulation at 2.0 Hz is a more sensitive monitoring method of neuromuscular function than single twitch stimulation (0.1-0.2 Hz).

Acetylcholine↗
PubMed1994

Kinetic analysis of neuromuscular blockade. II. Train-of-four fade induced by d-tubocurarine and alpha-bungarotoxin.

The degree of train-of-four (TOF) fade, i.e., the reduction of the fourth to the first twitch height in a train, induced by d-tubocurarine (d-TC) and alpha-bungarotoxin (alpha-BX) was investigated. The fade induced by d-TC was pronounced in comparison with that by alpha-BX, and the difference was analyzed using a kinetic model. Based on the assumptions: (1) Acetylcholine (ACh) binds to the nicotinic receptor and evokes twitch response. (2) The amount of released ACh is dependent on stimulus interval. (3) d-TC interacts competitively with the receptor. (4) alpha-BX interacts irreversibly with the receptor. It was suggested that the fade by d-TC and alpha-BX can be explained by the difference of the receptor occupancy by ACh which was caused by different interaction mechanisms of the two muscle relaxants with receptors.

Acetylcholine↗
PubMed1994

[Influence of vitamin D3 on inhibitory effect of vitamin K2 on bone loss in ovariectomized rats].

To evaluate whether the vitamin D3 level in the plasma influences the inhibitory effect of vitamin K2 on bone loss, vitamin K2 (25 mg/kg/day) was administered to ovariectomized (OVX) rats fed a diet containing vitamin D3 (V.D.(+)) or a diet deficient in vitamin D3 (V.D.(-)). After 3 months of treatment, the plasma 25-OH-vitamin D3 (25-OH-D3) level in the V.D(-)-sham group was about 1/3 of that in the V.D(+)-sham group. The plasma calcium level and alkaline phosphatase activity were also significantly lower in the V.D(-)-sham group than in the V.D(+)-sham group. In the V.D(+) group, the plasma 25-OH-D3 level in the vitamin K2 group was about 1.5 times higher than that in the OVX-control group. Ovariectomy resulted in a significant decrease in bone density, bone mineral content (BMC) and bone mineral density (BMD) of femurs in both the V.D(+) and V.D(-) groups. In the V.D(-) group, vitamin K2 had no marked effect on the bone loss. In the V.D(+) group, the bone density and BMD in the mid portion of the femur were significantly increased by vitamin K2 treatment. These findings suggest that the effect of vitamin K2 on bone loss is affected by the vitamin D3 level in the plasma.

Animals↗
PubMed1994

[Effect of bifemelane hydrochloride in rats on the improvement of the learning and memory impairments and prevention of neuronal damage following transient forebrain ischemia].

Modified four-vessel occlusion in rats caused loss of the passive avoidance response (PAR) and impaired the radial maze performance (RMP). We investigated the effectiveness of bifemelane hydrochloride (bifemelane) in restoring these abilities. After the RMP test, the hippocampal neuronal density following cerebral ischemia was observed histologically and the effect of bifemelane on it examined. Bifemelane was intraperitoneally administered at a dose of 1, 3, 10 mg/kg or 30 mg/kg twice before ischemia and daily following cerebral ischemia. The control rats were given physiological saline in the same manner. At a dose of 10 mg/kg, i.p., bifemelane significantly restored the PAR, which had been lost as a result of 5-min ischemia. At the same dose, it significantly restored the RMP, which had been impaired by 15-min ischemia and prevented neuronal damage in the CA2 region of the anterior hippocampus and the CA1, CA2 and CA3 regions of the posterior hippocampus. The correlation between the memory score and the neuronal density in the CA1 region of the posterior hippocampus was statistically significant. These results suggest that bifemelane might prevent the neuronal damage induced by ischemia and restore impaired learning and memory capabilities following cerebrovascular disease.

Animals↗
PubMed1994

Effects of menatetrenone on the decrease in calcium balance induced by vitamin K-deficient diet and sodium loading in rats.

The effects of menatetrenone (2-methyl-3-tetraprenyl-1,4-naphthoquinone, MK-4) on calcium balance were studied in male Sprague-Dawley rats. Experiment 1: Rats in metabolic cages that were fed a vitamin K-deficient diet and injected daily with latamoxef (100 mg/kg, i.p.) were either treated or untreated with MK-4 for 7 days. Daily food intake, urine volume and feces weight were determined, and calcium concentration in these samples was measured. Calcium balance was calculated as the difference between calcium intake and urinary and fecal calcium excretion. Cumulative calcium balance in the vitamin K-deficient group treated with latamoxef was lower than that in normal rats; this balance was significantly improved by MK-4 (1 and 10 mg/kg, s.c.) administered for 7 days. Experiment 2: Rats were fed a vitamin K-deficient diet containing 4.6% sodium chloride for 6 weeks. MK-4 was administered as a dietary supplement. Forty-eight-hour calcium balance, determined once a week, was significantly reduced compared with that of normal rats after 3 and 5 weeks; the balance was restored dose-dependently by MK-4 administration (1 and 10 mg/kg). Experiment 3: Rats were subjected to the same experimental conditions as experiment 2 for 6 weeks, and intestinal calcium transport was determined using an everted gut-sac technique. Calcium transport was reduced by the high sodium, vitamin K-deficient diet, and this reduction was restored by MK-4 administration (10 mg/kg). These results suggest that MK-4 improves the reduced calcium balance by increasing intestinal calcium absorption in these rats.

Alkaline Phosphatase↗