The predominant mechanism by which insulin activates glucose transport in muscle and adipose tissue is by affecting the redistribution of the facilitated hexose carriers, GLUT1 and GLUT4, from an ...intracellular site to the plasma membrane. A quantitative analysis of this process has been hampered by the lack of reliable determinations for kinetic constants catalyzed by each of these isoforms. In order to obtain such information, each transporter was expressed in Xenopus oocytes by the injection of mRNA encoding rat GLUT1 or GLUT4. Equilibrium exchange 3-O-methylglucose uptake was measured and the data fitted to a two-compartment model, yielding Km = 26.2 mM and Vmax = 3.5 nmol/min/cell for GLUT1 and Km = 4.3 mM and Vmax = 0.7 nmol/min/cell for GLUT4. Measurement of the abundance of cell surface transporters was accomplished by two independent protocols: photolabeling with the impermeant hexose analog 2-N-4-(1-azi-2,2,2-trifluoroethyl)benzoyl-1,3-bis(D-mannos-4 -yloxy)-2-propylamine and subcellular fractionation of oocytes. Data obtained by either technique revealed that the ratio of plasma membrane GLUT1 to GLUT4 was about 4; this paralleled the relative maximal velocities for hexose transport, indicating that the turn-over numbers for the two isoforms were the same. Moreover, measurement of the concentration of exofacially disposed transporters with 2-N-4-(1-azi-2,2,2-trifluoroethyl)benzoyl-1,3-bis(D-mannos-4 -yloxy)-2-propylamine allowed calculation of the turnover number to be about 20,000 min-1. These data indicate that, at low substrate concentrations, the catalytic efficiency of GLUT4 is significantly greater than GLUT1. Extrapolation to mammalian systems suggests that GLUT4 is responsible for virtually all of the hexose uptake in insulin-responsive targets, particularly in the presence of hormone.
The decision rules individuals use to judge wrongdoing committed inside corporations and other hierarchical organizations are not well understood. We explore this issue by asking random samples of ...individuals in Moscow, Tokyo, and Washington, D. C., to respond to four short vignettes describing acts of wrongdoing by people in corporations. The vignettes are experiments that manipulate the actor's mental state, the actor's position in the organization, and whether the actor's decision was influenced by others in the organization. We examine (1) the distribution of responsibility among people in the organization, (2) how individual responsibility affects the attribution of responsibility to the organization itself, and (3) cross-national differences in attributions. We find that both what the actors did (their deeds) and the position they occupied (their roles) significantly influence the responsibility attributed to them. The responsibility attributed to the organizations themselves is a function of the responsibility attributed to the actors inside the organization, but not a function of the independent variables in the experiments. Cross-national differences emerge with respect to the responsibility assigned both to individuals and to the organizations themselves. We discuss implications of these results for past and future work.
To address a role of mitogen-activated protein kinase (MAPK) in the regulation of glucose transport, we made a constitutively active mutant of MAPK kinase (MAPKK) and introduced it into 3T3-L1 ...preadipocytes by using a retrovirus-mediated transfection procedure. The deletion of 20 amino acids (those between and including 32 and 51) in the amino terminal region of Xenopus MAPKK and the replacement of serine residues on the 218 and 222 positions by glutamic acid (dSESE-MAPKK) let Xenopus MAPKK constitutively active. The isolated cell clones differently expressing dSESE-MAPKK (clone 219 higher expression, clone 233 lower expression) efficiently differentiated to adipocytes by a standard differentiation cocktail. Accordingly, the increased expression of dSESE-MAPKK protein during differentiation resulted in the increased basal MAPK activity in clone 219 adipocytes and, to a lesser extent, in clone 233 adipocytes. In contrast to clone 233 and parental adipocytes, basal 2-deoxyglucose uptake was enhanced fourfold in clone 219 adipocytes, in accordance with increased expression of GLUT1 mRNA and protein. Whereas GLUT4 mRNA was similarly expressed in all of the adipocytes, GLUT4 protein appeared to decrease in clone 219 adipocytes. More importantly, subcellular fractionation studies showed that the localization of both GLUT1 and GLUT4 in the plasma membranes (PMs) was markedly increased in the basal state in clone 219 adipocytes compared with that in clone 233 and parental adipocytes, in which both glucose transporters were preferentially located in intracellular compartments. Consequently, insulin-induced translocation of GLUT1 was abolished in clone 219 adipocytes, although the remaining intracellular GLUT4 was still responsive to insulin stimulation, which led to the movement to the PM. As combined effects on the situation of GLUT1 and GLUT4, the foldness of insulin stimulation of glucose transport based on the basal activity was reduced in cells expressing constitutively active MAPKK. These results imply that chronic activation of MAPK could be one of the mechanisms for insulin resistance.
We retrospectively reviewed 91 patients with epithelial ovarian cancer who underwent second-look operation (SLO). SLO identified a persistent tumor in 18 (19.8%) of 91 patients. Of these 18 patients, ...13 (72.2%) showed disease progression after SLO. Patients with a positive SLO in which the identification of the persistent disease was only possible by washing cytological study showed better prognosis than patients with macroscopic lesions. Of the 73 patients with a negative SLO, 12 (16.4%) developed recurrence after cessation of treatment. These 12 patients were. from stage 1c to 3 with Grade 2 and 3 tumors. The SLO findings were more sensitive than the serum tumor marker in identifying persistent disease. Also we reviewed 55 patients having no SLO. Among 57 cases in stage 1 and 2 with Grade 1 tumor, there were no cases of recurrence, regardless of whether they had SLO or not. Our results suggest that SLO findings correlate well with the patient's prognosis. SLO may not be needed for patients in stage 1 and 2 with Grade 1 tumor. Patients with advanced stage disease with Grade 2 and 3 tumors have high-risk for recurrence after negative SLO. While SLO is still of benefit in management of ovarian cancer, refinements are needed to determine its indication and scheduling.
In this paper we argue that differences in the conceptualization of individual actors in networks provide the most parsimonious explanation for differences that occur between American and Japanese ...views of sanctions and between actors in different role relationships within each society. Our empirical tests drew on respondents' hypothetical punishment choices and punishment rationales in surveys of Detroit, Michigan, and Yokohama and Kanazawa, Japan. As predicted, American views of punishments for everyday misdeeds were more likely to favor isolation or retribution and American rationales for imprisonment were significantly more retributive than in Japan. Within each culture, offenses between intimates were least likely to evoke isolative or retributive punishments whereas offenses between strangers were most likely to do so. We conclude by considering alternatives to our structuralist explanation of these findings and by suggesting some implications of legal culture for dispute resolution in the United States versus Japan.
Immature Teratoma of the Uterine Fundus IWANAGA, SHIGEAKI; SHIMADA, ATSUKO; HASUO, YASUYUKI ...
Kurume medical journal,
1993, Volume:
40, Issue:
3
Journal Article
Peer reviewed
Open access
An exceedingly rare case of extragonadal immature teratoma, which occurred primarily in the uterus, is described. The tumor developed into the pelvic cavity from the uterine fundus and consisted of ...ectodermal, mesodermal and endodermal derivatives. There were also significant amounts of immature elements; immature neuroepithelium with brisk mitotic activity, immature mesenchymal tissue, immature cartilage, immature striated muscle and immature hepatic tissue. Histologically, it was classified as a grade 3 immature teratoma. Treatment consisted of total simple hysterectomy followed by 2 courses of combination chemotherapy with vincristine, actinomycin D and cyclophosphamide (VAC). The patient was well and without evidence of recurrence at 5 years post-operatively.
Gap junctions between human endometrial epithelial cells were studied at various phases of the normal menstrual cycle by freeze-fracture electron microscopy. The junctions changed in number and size ...according to the phases of the menstrual cycle. Only small and few gap junctions were found in the early proliferative phase. In the early secretory phase the junctions were larger and found more often in the earlier phase. In the late secretory phase the junctions were much smaller than in the early secretory phase. The cyclical changes of the junctions may have a role in controlling the proliferation and differentiation of the endometrial epithelium.
Leptin, which is secreted from adipocytes, has a role in the regulation of appetite and energy expenditure. The thyrotropin receptor (TSH-R) was recently found in adipocytes. We examined the effects ...of TSH on leptin production and lipolysis in rat epididymal adipocytes. TSH decreased the concentration of leptin in the medium time (approximately 24 hours)- and dose (approximately 10(-7) mol/L)-dependently (half-maximal inhibition IC50 approximately 10(-9) mol/L). TSH also decreased the ob mRNA level approximately 55% in adipocytes. We confirmed the presence of TSH-R mRNA in the adipocytes by reverse transcription-polymerase chain reaction (RT-PCR). TSH stimulated glycerol release dose-dependently (IC50 approximately 10(-8) mol/L) in adipocytes. This TSH-induced glycerol release was further enhanced by adenosine deaminase (ADA). In summary, TSH reduced leptin production and stimulated lipolysis in rat epididymal adipocytes. Although the pathophysiological relevance of the regulation of leptin production and lipolysis by TSH is unknown, we speculate that TSH may affect the regulation of appetite and energy expenditure in pathophysiological states.
Fifty-one patients with stage III and IV ovarian adenocarcinoma underwent initial cytoreductive surgery at Kurume University Hospital between January 1982 and October 1985. They were assigned ...postoperatively by randomized trials to immunochemotherapy or chemotherapy alone. Of all 51 patients, long-term results of immunochemotherapy for 43 patients were evaluated versus radicality of initial cytoreductive surgery. As a result, the group of patients treated with immunochemotherapy tended to have a better prognosis than the group of patients treated with chemotherapy alone, whereas no statistical difference was observed between the two groups. Moreover, no significant difference was observed in the monitoring of OKT 4/8 ratio between the two groups. However, immunochemotherapy produced a favorable prognosis in the patients with residual disease of greater than 2cm in diameter at initial surgery. In conclusion, these data suggested that immunochemotherapy may have some impact on survival of patients with ovarian adenocarcinoma.
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