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T Okamura

Publications and source records attributed to T Okamura.

At least 361 records · Page 20Linked to original sources
PubMed1994

Foreign-body granuloma mimicking an extrahepatically growing liver tumor: report of a case.

We herein describe a 74-year-old woman with a foreign-body granuloma mimicking a liver tumor. Imaging studies revealed a pedunculated left lobe mass in the setting of chronic liver disease. She had a past history of a cholecystectomy as well as a previous gynecological operation. A left lateral segmentectomy was performed because of the possibility of a rupture. The dissected specimen showed a foreign-body granuloma caused by gauze. We believe this case to be a very unique granuloma, which should be kept in mind whenever making a diagnosis of a liver tumor particularly in a patient with chronic liver disease, who has a past history of abdominal surgery.

Aged↗
PubMed1994

Osteopenia in primary biliary cirrhosis and cirrhosis of the liver in women, evaluated by dual-energy X-ray absorptiometry.

To study bone involvement in primary biliary cirrhosis (PBC), we used dual-energy X-ray absorptiometry to measure bone mineral density (BMD) in Japanese women with PBC and with cirrhosis of the liver. In both groups, in each decade up to 60 years of age, the mean BMD of the lumbar spine was not significantly different from that in healthy Japanese women; however, in patients aged 60 years or more, the level was significantly lower both in the patients with PBC (P < 0.001) and in those with cirrhosis of the liver (P < 0.01). Patients with PBC were also examined by single-photon absorptiometry. The BMD of the radius in the patients with PBC was less changed than that of the lumbar vertebrae; thus, the bone changes in PBC seem to be greater in spongy than in cortical bone.

Absorptiometry, Photon↗
PubMed1994

Total body and regional bone mineral content in hemodialysis patients.

Bone mineral content (BMC) in the total body and lumbar spine was evaluated in 126 hemodialysis patients (60 males, 66 females) by dual photon absorptiometry with the Norland DBD 2600. Measurements of: 1) total body BMC divided by lean body mass (BMCTB/LBM), 2) bone mineral density (BMD) of total body, 3) BMD of four regional sections (head, trunk, pelvis, and legs), and 4) BMD of lumbar spine, generally showed a significant decrease in the hemodialysis patients compared to the reference population. However, arm BMD did not show a significant difference between patients and control populations. The z-score of BMCTB/LBM declined significantly throughout the duration of hemodialysis, although that of the lumbar spine BMD did not. It should be noted that the degree of decrease in BMC was more prominent in the total body measurement than in the lumbar spine measurement. There was preferential osteopenia of the total body in the hemodialysis patients. Although the lumbar spine BMD showed a lower value than the control population, the lumbar spine is not the recommended region to monitor the BMD change in hemodialysis patients.

Absorptiometry, Photon↗
PubMed1994

Predictors of postoperative distant recurrences in esophageal carcinoma.

Pathologic factors and the number of nucleolar organizer region proteins (AgNORs) were evaluated as predictors of postoperative recurrence in distant organs in 92 patients with curatively resected esophageal carcinoma. The rate of distant recurrence was significantly higher in patients with venous invasion (53%; 19 of 36) than in those without invasion (21%; 12 of 56) (p < 0.01) and was also higher in patients with an AgNOR score greater than or equal to 4 (49%; 19 of 39) than in those with an AgNOR score less than 4 (23%; 12 of 53) (p < 0.02). The rate of recurrence was significantly higher in patients with both venous invasion and AgNOR score greater than or equal to 4 (67%; 16 of 24) than in the other patients. These findings indicate that the combination of venous invasion and a high AgNOR score predicts distant postoperative recurrences in patients with curatively resected esophageal carcinoma.

Adult↗
PubMed1994

Malignant lymphoma of the scalp at the site of a previous blunt trauma: report of two cases.

We describe two cases with malignant lymphoma presented as scalp tumors. Both patients had slowly growing subcutaneous lymphoma masses in the scalp after head trauma. In the first case, the scalp lymphoma presented as a recurrent disease during complete remission of her systemic lymphoma after chemotherapy. In the second case, the tumor involved the scalp, subjacent skull, and intracranial space without systemic manifestation. These cases represent examples of a possible relationship between head trauma and the development of between head trauma and the development of tumors involving the brain and its coverings.

Aged↗
PubMed1994

Nitric oxide (NO)-mediated, vasodilator nerve function and its susceptibility to calcium antagonists.

Our pharmacological and immunohistochemical studies have demonstrated that nitric oxide (NO) or a substance that liberates NO plays a crucial role in the neurogenic relaxation of isolated cerebral arteries of dog and monkey. Relaxation caused by nerve stimulation by nicotine or electrical pulses in dog cerebral arteries without the endothelium were attenuated by Cd2+, a non-selective Ca2+ channel antagonist. Increase in cyclic GMP by nicotine was also suppressed by Cd2+, but not by nicardipine. Treatment with capsaicin did not influence the relaxant responses of the endothelium-denuded cerebral arteries to nerve stimulation. These results suggest that neurotransmission in vasodilator nerves innervating dog cerebral arteries is mainly mediated by NO, synthesized by an NO synthase which is activated by Ca2+ influx through non-L-type Ca2+ channel, but not by vasodilator peptides.

Animals↗
PubMed1994

Glandular stomach hemorrhage induced by high dose saccharin in young rodents.

In studies primarily designed to evaluate the effects of saccharin and silicate on the urinary bladders of rodents, hemorrhage of the glandular stomach was observed in high incidence. It occurred in young rats with high doses of saccharin (7.5% sodium saccharin; 6.3% acid saccharin), with no difference between male and female F344 rats fed during ages 5 to 15 weeks. no difference between sodium saccharin and acid saccharin, and was reversible, even with continued saccharin administration. Sodium silicate (0.38, 1.13, 2.26% of the diet) had no influence on gastric hemorrhage. Iron deficiency anemia has been observed in young rats fed high dietary levels of saccharin, and the present results suggest that gastric hemorrhage contributes to its etiology.

Animals↗
PubMed1994

A clinicopathological evaluation of nucleolar organizer region proteins in human breast carcinoma.

The number of nucleolar organizer region proteins (NORs) identified by silver staining (Ag) was studied in 106 primary breast carcinomas. The AgNOR score (mean +/- SD) in tumours smaller than 2 cm was significantly lower than that in tumours larger than 2 cm (P < 0.05). However, there was no significant difference according to other clinicopathological characteristics. According to postoperative distant recurrence, the AgNOR count was significantly higher in the group with recurrence than in the group without recurrence (P < 0.05). Further, the survival rate was significantly lower in the high AgNOR score (> or = 3) group than in the low score (< 3) group (P < 0.01). The present study indicates that the AgNOR score in human breast cancer cells is useful for evaluating cell proliferative activity and may help predict postoperative distant recurrence and, ultimately, the postoperative prognosis of patients.

Adult↗
PubMed1994

The extent and number of metastatic lymph nodes limit the efficacy of lymphadenectomy in patients with oesophageal carcinoma.

The extent and number of metastatic lymph nodes in 52 patients with oesophageal carcinoma involving more than one lymph node were analysed to determine the efficacy of lymphadenectomy. The patients were divided into two groups according to the number of metastatic lymph nodes, group A: 1-4 nodes (34 cases) and group B: 5 or more nodes (18 cases). The survival of all patients in group A was statistically better than that of the patients in group B (P = 0.02). In cases where metastatic nodes were restricted to one region, the survival of patients in group A was significantly better than that of patients in group B (P = 0.006). By contrast, in cases where metastatic nodes extended to two or more regions, there was no difference between the groups. The present study suggests that lymphadenectomy is effective only for patients with 1-4 metastatic nodes that are restricted to a single region. Lymphadenectomy is less efficacious in cases with five or more metastatic nodes, even when the nodes are restricted to one region, and is similarly ineffective in cases with metastatic nodes extending to two or more regions, regardless of the number of positive nodes.

Adult↗
PubMed1994

Responses to histamine and acetylcholine in isolated monkey mesenteric veins versus arteries.

OBJECTIVE: The aim was to analyse and compare mechanisms of histamine or acetylcholine action in mesenteric venous and arterial strips obtained from Japanese monkeys. METHODS: Monkey mesenteric arterial and venous strips were suspended for isometric tension recording in modified Ringer-Locke solutions, and responses of the strips precontracted with prostaglandin F2 alpha to histamine or acetylcholine were compared. RESULTS: Histamine (2 x 10(-8) M-10(-5) M) produced a concentration related relaxation in the arteries and veins. The arterial relaxation was slightly but significantly attenuated by endothelial denudation [57.1(SEM 11.2)% inhibition at 10(-7) M, n = 14, p < 0.05] and treatment with 10(-6) M chlorpheniramine [26.7(6.7)% inhibition at 10(-7) M, n = 10, p < 0.05] or 10(-5) M methylene blue [31.5(11.2)% inhibition at 10(-7) M, n = 9, p < 0.05], and markedly suppressed by 10(-5) M cimetidine [96.8(1.2)% inhibition at 10(-7) M, n = 13, p < 0.001]. Indomethacin (10(-6) M) was without effect. On the other hand, relaxant responses to histamine of the venous strips were not influenced by endothelial denudation and treatment with chlorpheniramine or indomethacin but were abolished by treatment with cimetidine. Removal of the endothelium did not alter the venous relaxation caused by acetylcholine (10(-8) M-10(-4) M) but almost abolished the response to Ca2+ ionophore A23187 (10(-7) M) and substance P (10(-7) M). The acetylcholine induced relaxation was reversed to a contraction by indomethacin. CONCLUSIONS: Histamine-induced relaxations of monkey mesenteric arteries seem to be associated mainly with activation of the H2 receptor subtype in smooth muscle and partially mediated by relaxing factor liberated by stimulation of the H1 subtype in the endothelium, whereas the mesenteric venous relaxation seems to be due exclusively to a mediation of H2 receptors. Acetylcholine-induced relaxations of venous strips appear to be caused by vasodilator prostanoids, possibly prostaglandin I2, liberated from subendocardial tissues.

Acetylcholine↗
PubMed1994

A comparative study of partial primary structures of the catalytic region of mammalian protein C.

Protein C (PROC) is a plasma vitamin K-dependent zymogen of a serine protease which regulates blood-clotting cascade through proteolytic inactivation of the non-enzymatic cofactors of blood coagulation, Va and VIIIa. We characterized the partial nucleotide and amino acid sequences for the catalytic domain of PROC in six mammalian species, rhesus monkey, dog, cat, goat, horse and mouse, and compared these sequences with known ones from humans, the bovine and rat. By using a pair of primers based on the nucleotide sequences from human and bovine PROC cDNA, the PROC gene fragments were enzymatically amplified from their genomic DNAs and were sequenced by the dideoxy-termination method. The cloned PROC gDNA encoded a part of the heavy chain of PROC including the lesions of active site residues corresponding to human PROC Asp-257 and Ser-360. Comparison of the sequences from these species revealed that there was a high degree of homology at the nucleotide and amino acid levels; from 69% to 96% of the amino acids in the catalytic region were identical among the nine species including humans, the bovine and rat. The locations of five Cys residues as well as the putative carbohydrate attachment sites were evolutionally conserved. All the amino acids recognized in the human abnormal PROC variants were conserved across species, suggesting their functional importance, and a comparison of the conserved residues among PROC from multiple species will provide considerable information in the investigations of PROC functions.

Amino Acid Sequence↗
PubMed1994

Involvement of interferon-gamma and macrophage colony-stimulating factor in pathogenesis of haemophagocytic lymphohistiocytosis in adults.

We investigated the role of monocyte/macrophage-activating cytokines in pathogenesis of haemophagocytic lymphohistiocytosis (HLH) in 21 adult patients. Sera from patients with active HLH contained extremely high levels of macrophage colony-stimulating factor (M-CSF) and of interferon-gamma (IFN-gamma). These levels returned to almost normal during remission. Neither interleukin-4 nor granulocyte/macrophage colony-stimulating factor could be detected. Active HLH sera also contained high concentrations of inflammatory monokines, such as interleukin-6 (IL-6) and tumour necrosis factor-alpha (TNF-alpha). Serum concentrations of soluble CD8 and soluble interleukin-2 receptor were extremely high during active HLH, and returned to virtually normal levels during remission. Circulating CD2+ T-cells obtained from patients with active HLH spontaneously secreted M-CSF and IFN-gamma in vitro, whereas circulating monocytes did not produce detectable levels of both M-CSF and IFN-gamma, but produced high levels of IL-6 and TNF-alpha. These findings suggest that IFN-gamma and M-CSF at least partly from T-cells, such as CD8+ T-cells, might contribute to activation of monocytes or histiocytes, resulting in the up-regulated monokine production and haemophagocytosis in HLH.

Adolescent↗
PubMed1994

Mechanism underlying substance P-induced relaxation in dog isolated superficial temporal arteries.

1. In helical strips of dog superficial temporal arteries with intact endothelium, substance P elicited a concentration-related relaxation with an EC50 of 2.8 (2.4-3.2) x 10(-10) M. 2. The relaxant response to the peptide in low concentrations (1-4 x 10(-10) M) sufficient to produce approximately half maximal relaxation was not inhibited by indomethacin, but was markedly suppressed by NG-nitro-L-arginine (L-NOARG), a nitric oxide (NO) synthase inhibitor, and by endothelium denudation. 3. High concentration (10(-7) M) of substance P produced marked relaxations in endothelium-intact strips. Removal of the endothelium attenuated the relaxation, and indomethacin or tranylcypromine suppressed the endothelium-independent relaxation. In indomethacin-treated strips with intact endothelium, L-NOARG attenuated but did not abolish the relaxation. The residual, L-NOARG-resistant relaxation was not significantly inhibited by ouabain, glibenclamide or tetraethylammonium. 4. Substance P (10(-7) M) increased the levels of cyclic GMP and cyclic AMP. The increase in cyclic GMP was abolished by endothelium denudation and treatment with L-NOARG, whereas the cyclic AMP increment was abolished by indomethacin. 5. Three different mechanisms may be involved in the substance P-induced relaxation: (1) an endothelium-dependent relaxation mediated by the release of NO from the endothelium, resulting in an increase of cyclic GMP (low and high concentrations of the peptide); (2) an endothelium-independent relaxation in association with cyclic AMP increment caused by prostaglandin I2 released from subendothelial tissues (high concentration), and (3) another endothelium-dependent relaxation possibly mediated by unidentified mediator(s) released from the endothelium (high concentration).

Analysis of Variance↗
PubMed1994

Analysis of the partial nucleotide sequences and deduced primary structures of the protease domains of mammalian blood coagulation factors VII and X.

In order to obtain sequence data for the blood coagulation factor VII and factor X in several mammalian species, we amplified and sequenced the DNA segments of exon VIII from each gene by means of the polymerase chain reaction (PCR) method. The DNA segments from the following species were successfully amplified: factor VII from the rhesus monkey and dog, and factor X from the rhesus monkey, Syrian hamster and rat. In each factor, the nucleotide sequences and predicted primary structures of the protease domain showed a high degree of homology among species; amino acid identities of approximately 68%-92% and 80%-98% were demonstrated among species in factor VII and factor X, respectively. The locations of the active site residues and five Cys residues were evolutionarily conserved in both factors. Interestingly, the amino acids involved in the human genetic variants, both factor VII 304-Arg and factor X 326-Arg, were always conserved across species. The data presented here will be helpful for investigating human genetic variants of factor VII or X, and will provide considerable information for constructing in vitro site-specific mutants of these factors.

Amino Acid Sequence↗
PubMed1994

Comparative studies of genes encoding thermostable L-2-halo acid dehalogenase from Pseudomonas sp. strain YL, other dehalogenases, and two related hypothetical proteins from Escherichia coli.

We have determined the nucleotide sequence of the gene encoding thermostable L-2-halo acid dehalogenase (L-DEX) from the 2-chloroacrylate-utilizable bacterium Pseudomonas sp. strain YL. The open reading frame consists of 696 nucleotides corresponding to 232 amino acid residues. The protein molecular weight was estimated to be 26,179, which was in good agreement with the subunit molecular weight of the enzyme. The gene was efficiently expressed in the recombinant Escherichia coli cells: the amount of L-DEX corresponds to about 49% of the total soluble proteins. The predicted amino acid sequence showed a high level of similarity to those of L-DEXs from other bacterial strains and haloacetate dehalogenase H-2 from Moraxella sp. strain B (38 to 57% identity) but a very low level of similarity to those of haloacetate dehalogenase H-1 from Moraxella sp. strain B (10%) and haloalkane dehalogenase from Xanthobacter autotrophicus GJ10 (12%). By searching the protein amino acid sequence database, we found two E. coli hypothetical proteins similar to the Pseudomonas sp. strain YL L-DEX (21 to 22%).

Amino Acid Sequence↗
PubMed1994

Human uterine arterial relaxation induced by nitroxidergic nerve stimulation.

Uterine arterial strips obtained from humans responded to nicotine with a contraction, which was abolished by prazosin. In the arteries treated with the alpha 1-receptor antagonist and partially contracted with serotonin, nicotine produced a relaxation that was not influenced by treatment with atropine or timolol and endothelium denudation but was abolished by hexamethonium, oxyhemoglobin, and NG-nitro-L-arginine (L-NNA). The inhibitory effect of L-NNA was reversed by L- but not D-arginine. Relaxations induced by nitroglycerin and nitric oxide (NO) were not affected by L-NNA but were abolished by oxyhemoglobin. Transmural electrical stimulation relaxed the arterial strips treated with prazosin; this response was abolished by L-NNA and restored by L-arginine. Histochemical study with NO synthase antiserum demonstrated the presence of immunoreactive nerve fibers in the adventitia. It may be concluded that human uterine arteries are innervated by vasodilator nerves that liberate NO as a neurotransmitter after chemical or electrical stimulation. Predominant vasoconstriction due to nerve stimulation appears to be associated with activation of alpha 1-adrenoceptors by neurogenic norepinephrine.

Adult↗