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Noah A Goldman Ellen B Katz Alan S Glenn Richard H Weldon Joan G Jones Uticia Lynch Melissa J Fezzari Carolyn D Runowicz Gary L Goldberg Maureen J Charron 《Modern pathology》2006,19(11):1429-1436
Glucose is provided to cells by a family of glucose transport facilitators known as GLUTs. These transporters are expressed in a tissue specific manner and are overexpressed in many primary tumors of these tissues. Regulation of glucose transport facilitator expression has been demonstrated in endometrial tissue and endometrial adenocarcinoma. The following experiments were conducted to quantify and localize the expression of GLUT1 and GLUT8 in benign endometrium and compare this expression to endometrial cancer. Endometrial tissue samples were obtained from random hysterectomy specimens of patients with benign indications for surgery and endometrial cancer. Immunoblot and immunolocatization studies were performed using GLUT1 and GLUT8 specific antisera. Endometrial samples from 65 women who had undergone hysterectomy were examined (n=38 benign, n=27 malignant). A 44 and a 35.4 kDa immunoreacive species was demonstrated in endometrium and endometrial cancer for GLUT1 and GLUT8, respectively. Upregulation of GLUT1 expression was demonstrated with increasing grade of tumors (P<0.002). GLUT8 expression was increased in all tumor subtypes compared to atrophic endometrium (P<0.001). Apical localization by GLUT1 and GLUT8 was demonstrated in endometrial glands. GLUT1 and GLUT8 demonstrated diffuse intracellular localization in the cancer subtypes. GLUT1 and GLUT8 are expressed in both human endometrium and endometrial cancer. There appears to be a step-wise progression in GLUT1 and GLUT8 expression as tumor histopathology worsens. GLUT1 and GLUT8 may be important markers in tumor differentiation, as well as providing energy to rapidly dividing tumor cells. 相似文献
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Alan A Arslan Anne Zeleniuch-Jacquotte Annekatrin Lukanova Yelena Afanasyeva Joseph Katz Mortimer Levitz Giuseppe Del Priore Paolo Toniolo 《Cancer epidemiology, biomarkers & prevention》2006,15(11):2123-2130
Epidemiologic evidence suggests that a full-term pregnancy may affect maternal risk of breast cancer later in life. The objective of this cross-sectional study was to compare circulating levels of maternal hormones affecting breast differentiation (human chorionic gonadotropin and prolactin) and proliferation [alpha-fetoprotein, insulin-like growth factor I (IGF-I), and estradiol] between women at a low to moderate risk (Asians and Hispanics), as compared with women at a high risk for breast cancer (Caucasians and African-Americans). Between May 2002 and December 2004, a total of 586 pregnant women were approached during a routine prenatal visit. Among them, 450 women (206 Caucasian, 126 Asian, 88 Hispanic, and 30 African-American) met the inclusion criteria and signed the informed consent. Only singleton pregnancies were considered. Blood samples were drawn during the second trimester of pregnancy. Laboratory analyses were done using the IMMULITE 2000 immunoassay system. Gestational age standardized mean levels of estradiol, IGF-I, and prolactin were significantly higher in Hispanic women compared with Caucasian women. Mean concentration of IGF-I was significantly higher in African-American women compared with Caucasian and Asian women. No significant differences in pregnancy hormone levels were observed between Caucasian and Asian (predominantly second-generation Chinese) women in this study. Irrespective of ethnicity, women who had their first pregnancy had substantially higher mean levels of alpha-fetoprotein, human chorionic gonadotropin, estradiol, and prolactin compared with women who previously had at least one full-term pregnancy. These data suggest that circulating pregnancy hormone levels may explain some of the ethnic differences in breast cancer risk. 相似文献
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Ira R Katz Marcia Rupnow Chris Kozma Lon Schneider 《The American journal of geriatric psychiatry》2004,12(5):499-508
OBJECTIVE: Authors evaluated the association between use/dosage of risperidone (RIS) and falls in a residential-care dementia population. METHODS: Authors performed secondary analysis of data from ambulatory patients in a randomized, double-blind, placebo-controlled, 12-week trial of three RIS dosages (0.5 mg/day, 1 mg/day, 2 mg/day). Outcomes included number of fallers, rate of falls, and time until the first fall after randomization. Additional analyses evaluated wandering as a potential moderating or mediating variable. RESULTS: The ambulatory sample included 537 subjects. Of those, 22.3% on placebo, 18.0% on RIS 0.5 mg/day, 12.7% on 1 mg/day, and 27.3% on 2 mg/day, respectively, fell during the trial. The difference between the RIS 1 mg/day group and placebo was significant, with a significantly lower hazard ratio in the RIS 1-mg/day group than placebo. Wandering was associated with an increased risk of falls. Among 205 patients with the highest levels of wandering at baseline, RIS 1 mg/day was associated with approximately a 70% reduction in risk for falls versus placebo condition. However, in those with the lowest levels of wandering at baseline, RIS 2 mg/day may have increased the risk of falls. CONCLUSIONS: Evaluating the benefits versus risks of risperidone in patients with dementia is complex and must consider multiple outcomes as a function of dose. At 1 mg/day, RIS was associated with decreased falls, especially in patients who exhibit wandering. However, at 2 mg/day, it may increase the risk of falls in ambulatory individuals with low levels of wandering. 相似文献
35.
This study provides additional information on the psychometric properties of the Sexual Aversion Scale (SAS). Results suggest a positive relationship between sexual aversion, generalized anxiety, and history of sexual victimization. Variables such as age and religiosity were unrelated to scores on the SAS, although females reported significantly more sexual anxiety than males. The factor structure of the SAS is described and suggests that sexual aversion is a multifaceted problem with at least three and possibly four different dimensions. 相似文献
36.
We examined the effects of the polycationic antibiotic, neomycin, on the function of dispersed bovine parathyroid cells. Neomycin caused a reversible, dose-dependent inhibition of low calcium (Ca++)-stimulated PTH release, with half-maximal inhibition at 30 microM. Maximal inhibition (with 200 microM neomycin) was not additive with the suppressive effects of high (2 mM) Ca++. Neomycin also inhibited dopamine-stimulated cAMP accumulation by 90-98% at 100-200 microM, with a half-maximal effect at 40-50 microM. This action was reversible and was blocked by preincubating the cells overnight with 0.5 microgram/ml pertussis toxin. In addition to its suppressive effects on cAMP metabolism and PTH release, neomycin stimulated the accumulation of inositol phosphates and produced a transient increase in the cytosolic Ca++ concentration (Cai) in fura-2-loaded parathyroid cells. The neomycin-evoked spike in Cai persisted despite removal of extracellular Ca++, indicating that it arises from intracellular Ca++ stores. Exposure of cells to elevated magnesium (Mg++) concentrations elicited a similar spike in Cai but blocked the spike in Cai in response to subsequent addition of neomycin and vice versa. Thus, Mg++ and neomycin mobilize Ca++ from the same intracellular store(s). These results indicate that a polycation, neomycin, closely mimics the effects of polyvalent cations on parathyroid function, suggesting that both agents regulate parathyroid function via similar biochemical pathways. 相似文献
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Venous duplex imaging: should it replace hemodynamic tests for deep venous thrombosis? 总被引:2,自引:0,他引:2
A J Comerota M L Katz L L Greenwald E Leefmans M Czeredarczuk J V White 《Journal of vascular surgery》1990,11(1):53-9; discussion 59-61
Noninvasive diagnosis of deep venous thrombosis has traditionally relied on detection of alterations in venous hemodynamics. Although phleborheography is among the most sensitive tests, it is inadequate for diagnosing infrapopliteal and nonocclusive proximal thrombi and for surveillance of patients at high risk for deep venous thrombosis. Venous duplex imaging is a new technique being rapidly accepted, however, without the same critical analysis given to previous diagnostic modalities. The purpose of this study is to evaluate the diagnostic acumen of venous duplex imaging compared to phleborheography and ascending phlebography in two distinct patient groups, and to determine whether patient selection, and thus the location or magnitude of thrombi have significant influence on these diagnostic tests. One hundred ten extremities in 103 patients were prospectively evaluated with venous duplex imaging, phleborheography, and ascending phlebography within the same 24-hour period. Patients were categorized into one of two groups: Diagnostic--patients evaluated because of clinical suspicion of acute deep venous thrombosis; and Surveillance--patients at high risk of postoperative deep venous thrombosis after total joint replacement, but not symptomatic. Patients in the diagnostic group had a greater frequency of deep venous thrombosis (p less than 0.001) and significantly more occluding above-knee thrombi (p = 0.054) compared to those in the surveillance group. Phleborheography detected 73% (27/37) of above-knee thrombi in the diagnostic group compared to 29% (2/7) in the surveillance group (p = 0.036). This difference was not noted with venous duplex imaging, which detected 100% of above-knee thrombi in both diagnostic and surveillance groups and 78% (7/9) of all below-knee thrombi.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献