The Tohoku journal of experimental medicine
-
Tohoku J. Exp. Med. · Jan 1995
Modulation of protein kinase C produces glucose-dependent alterations in hemodynamics and metabolism in the perfused liver in fasted rats.
Protein kinase C (PKC) has been suggested to be involved in the regulation of hepatic blood flow and metabolism. To confirm the role of PKC, we studied the effects of active and inactive PKC modulators on hemodynamics and metabolism in the perfused rat liver. In addition, the influence of glucose concentration in the medium was studied. ⋯ However, H-7, a relatively specific PKC inhibitor, at a concentration of 33 microM attenuated the effects of PMA. The effects of PMA were enhanced by an increase in n-glucose concentration from 10 to 25 mM but not by an increase in L-glucose concentration. These results suggest that modulation of PKC exerts glucose-dependent influences on hepatic flow and metabolism.
-
Tohoku J. Exp. Med. · Oct 1993
Case ReportsTwo cases of thiamine deficiency-induced lactic acidosis during total parenteral nutrition.
Two cases of severe lactic acidosis induced by total parenteral nutrition (TPN) are reported. Both cases were admitted to our department for the surgical treatment of advanced gastric cancer, and subsequently underwent TPN because of poor nutritional status. Following the initiation of TPN, both patients went into an unstable circulatory state following shock. ⋯ One case died of irreversible shock. The other case similarly exhibited a deteriorated cardiovascular state but promptly responded to the administration of thiamine and was resuscitated. The blood thiamine level was low in both individuals, and the two patients were subsequently diagnosed as having thiamine deficiency-induced lactic acidosis.
-
Tohoku J. Exp. Med. · Mar 1993
Prognostic significance of simultaneous infiltration of HLA-DR-positive dendritic cells and tumor infiltrating lymphocytes into human esophageal carcinoma.
The distribution of HLA-DR-positive dendritic cells (DR+DCs) and tumor infiltrating lymphocytes (TILs) was investigated in 67 patients with squamous cell carcinoma of the esophagus. DR+DCs were chiefly present among the cancer cell nests, and few were seen in the stroma. As clusters, UCHL-1-positive T-cells (UCHL1-Ts) were detected in the tissue around the cancer cell nests and as individual cells within tumor nests. ⋯ In addition, a few OPD4-positive helper/inducer T cells were found among cancer cells, and were densely present in the stroma. A correlation was demonstrated between the number of DR+DCs and UCHL1-Ts in each patient (R = 0.4547, p < 0.01). In addition, dense tumor infiltration by both DR+DCs and UCHL1-Ts within the cancer cell nests was related to a better prognosis (p < 0.01).
-
The bladder and urethral activities during the rhythmic bladder contractions were evaluated before and after the intraarterial administration of methylene blue, which prevents the activation of soluble guanylate cyclase. The methylene blue produced an increase in the bladder activity and a decrease in the urethral smooth muscle relaxant response induced with bladder contraction. The L-arginine/nitric oxide pathway seems to modulate the vesicourethral function.
-
Tohoku J. Exp. Med. · Oct 1992
Comparative StudyDNA repair pathways in mammalian cells analyzed by isolation of ACNU-sensitive Chinese hamster ovary cells.
1-[(4-amino-2-methyl-5-pyrimidinyl)methyl]-3-(2-chloroethyl)-3- nitrosourea hydrochloride (ACNU) causes chloroethylation of DNA strand followed by cross linking through an ethylene bridge. We recently isolated two ACNU sensitive mutants from mutagenized Chinese hamster ovary cells, and found them to be new drug sensitive recessive mutants (Hata et al. 1991). The O6-methyl guanine DNA methyl transferase (MT) activities of these cells were undetectable as the parental cell line, indicating that the sensitivity of the mutant cell lines to ACNU was not due to the decreased cellular level of this enzyme. ⋯ The other mutant, CNU1 showed hypersensitivity only to chlorethylating agents (ACNU, CCNU) and exhibited a slightly reduced unscheduled DNA synthesis (UDS) induced by UV. It is, therefore, suggestive that this mutant is defective in a specific step of DNA repair systems, which is important for the processing of DNA damages produced by ACNU. Only cell lines from the complementation group 1 and 4 out of 7 established complementation groups of UV-sensitive CHO mutants were more sensitive to ACNU than UVS1 and CNU1, indicating some steps of excision repair pathways as well as specific repair system play important roles in repairing ACNU-induced DNA damages.