Citations

Context: Testosterone (Te) depletion in aging men in principle could reflect deficits in the hypothalamus, pituitary gland, or testis. Available pharmacological studies of possible failure of Leydig cell steroidogenesis remain inconclusive. Objective: The objective of the study was to assess Te secretion in older and young men in response to near physiological LH stimulation. Intervention: Pulsatile iv infusion of recombinant human LH was administered for 2 d to stimulate Te secretion during suppression of endogenous LH concentrations with a potent selective GnRH receptor antagonist (ganirelix). Subjects/Context: Healthy older (aged 60–73 yr, n = 8) and young (19–30 yr, n = 13) men were studied in an academic setting. Measures: Pulsatile LH and Te concentrations on the second day of exogenous LH stimulation were measured. Results: Serum ganirelix concentrations and infused LH pulse increments were similar by age. In contrast, older subjects manifested: 1) reduced mean Te concentrations (P = 0.016), Te peak heights (P = 0.014), increments (P = 0.010), summed areas (P < 0.013), and interpeak Te concentrations (P = 0.023); 2) decreased Te to LH concentration ratios (P = 0.002); 3) diminished LH-Te feed-forward synchrony (P = 0.020); and 4) a blunted amplitude (P = 0.036) and advanced phase (P = 0.013) of diurnal Te rhythms. Conclusion: A novel regimen of pulsatile LH stimulation for 48 h during GnRH receptor blockade unmasks deficits in pulsatile, basal, synchronous, and nyctohemeral Te secretion in healthy older men. These findings do not exclude concomitant defects in GnRH outflow and/or Te-negative feedback in the aging male.

Abstract Purpose: Advanced-stage epithelial ovarian cancer has a poor prognosis with long-term survival in less than 30% of patients. When the disease is detected in stage I, more than 90% of patients can be cured by conventional therapy. Screening for early-stage disease with individual serum tumor markers, such as CA125, is limited by the fact that no single marker is up-regulated and shed in adequate amounts by all ovarian cancers. Consequently, use of multiple markers in combination might detect a larger fraction of early-stage ovarian cancers. Experimental Design: To identify potential candidates for novel markers, we have used Affymetrix human genome arrays (U95 series) to analyze differences in gene expression of 41,441 known genes and expressed sequence tags between five pools of normal ovarian surface epithelial cells (OSE) and 42 epithelial ovarian cancers of different stages, grades, and histotypes. Recursive descent partition analysis (RDPA) was performed with 102 probe sets representing 86 genes that were up-regulated at least 3-fold in epithelial ovarian cancers when compared with normal OSE. In addition, a panel of 11 genes known to encode potential tumor markers [mucin 1, transmembrane (MUC1), mucin 16 (CA125), mesothelin, WAP four-disulfide core domain 2 (HE4), kallikrein 6, kallikrein 10, matrix metalloproteinase 2, prostasin, osteopontin, tetranectin, and inhibin] were similarly analyzed. Results: The 3-fold up-regulated genes were examined and four genes [Notch homologue 3 (NOTCH3), E2F transcription factor 3 (E2F3), GTPase activating protein (RACGAP1), and hematological and neurological expressed 1 (HN1)] distinguished all tumor samples from normal OSE. The 3-fold up-regulated genes were analyzed using RDPA, and the combination of elevated claudin 3 (CLDN3) and elevated vascular endothelial growth factor (VEGF) distinguished the cancers from normal OSE. The 11 known markers were analyzed using RDPA, and a combination of HE4, CA125, and MUC1 expression could distinguish tumor from normal specimens. Expression at the mRNA level in the candidate markers was examined via semiquantitative reverse transcription-PCR and was found to correlate well with the array data. Immunohistochemistry was performed to identify expression of the genes at the protein level in 158 ovarian cancers of different histotypes. A combination of CLDN3, CA125, and MUC1 stained 157 (99.4%) of 158 cancers, and all of the tumors were detected with a combination of CLDN3, CA125, MUC1, and VEGF. Conclusions: Our data are consistent with the possibility that a limited number of markers in combination might identify >99% of epithelial ovarian cancers despite the heterogeneity of the disease.

Abstract Purpose: Epithelial ovarian cancers are thought to arise from flattened epithelial cells that cover the ovarian surface or that line inclusion cysts. During malignant transformation, different histotypes arise that resemble epithelial cells from normal fallopian tube, endometrium, and intestine. This study compares gene expression in serous, endometrioid, clear cell, and mucinous ovarian cancers with that in the normal tissues that they resemble. Experimental Design: Expression of 63,000 probe sets was measured in 50 ovarian cancers, in 5 pools of normal ovarian epithelial brushings, and in mucosal scrapings from 4 normal fallopian tube, 5 endometrium, and 4 colon specimens. Using rank-sum analysis, genes whose expressions best differentiated the ovarian cancer histotypes and normal ovarian epithelium were used to determine whether a correlation based on gene expression existed between ovarian cancer histotypes and the normal tissues they resemble. Results: When compared with normal ovarian epithelial brushings, alterations in serous tumors correlated with those in normal fallopian tube (P = 0.0042) but not in other normal tissues. Similarly, mucinous cancers correlated with those in normal colonic mucosa (P = 0.0003), and both endometrioid and clear cell histotypes correlated with changes in normal endometrium (P = 0.0172 and 0.0002, respectively). Mucinous cancers displayed the greatest number of alterations in gene expression when compared with normal ovarian epithelial cells. Conclusion: Studies at a molecular level show distinct expression profiles of different histologies of ovarian cancer and support the long-held belief that histotypes of ovarian cancers come to resemble normal fallopian tube, endometrial, and colonic epithelium. Several potential molecular markers for mucinous ovarian cancers have been identified.

Abstract Epithelial ovarian cancer (EOC) is the leading cause of death among all gynecologic cancers in the United States. Because women who are diagnosed with early stage disease have a better prognosis than women diagnosed with late stage disease, early detection represents a potentially practical approach to reduce the mortality associated with EOC. Unfortunately, no single screening test has proven to be effective for this purpose, and a valid and feasible screening program to detect early stage EOC in the general population has not yet been devised. Consequently, research has focused on coupling two or more screening modalities to improve program validity and feasibility. Serum cancer antigen 125 (CA125) and a soluble isoform of the epidermal growth factor receptor (p110 sEGFR) have been studied individually as biomarkers of ovarian cancer. In this study, we compare serum CA125 levels and sEGFR concentrations in women with EOC to women with benign gynecologic conditions of ovarian and non-ovarian origin. We show that serum sEGFR concentrations are lower in patients with EOC than in women with benign gynecologic conditions, whereas serum CA125 levels are higher in patients to EOC compared with women with benign gynecologic conditions. These data also reveal that age and serum sEGFR concentrations modify the association between CA125 levels and EOC versus benign gynecologic disease. Hence, age- and sEGFR-dependent CA125 cutoff thresholds improve the ability of CA125 to discern EOC patients from women with benign ovarian tumors and non-ovarian gynecologic conditions. Our analyses show that parallel testing with fixed sEGFR and CA125 cutoff thresholds optimizes sensitivity to detect EOC, whereas serial testing with age- and sEGFR-dependent CA125 cutoff thresholds optimizes test specificity, and overall accuracy to discern patients with EOC from women with benign ovarian and non-ovarian gynecologic conditions. The combined use of serologic sEGFR and CA125, thus, has improved utility for screening and diagnosing EOC, which may increase the positive predictive value of a multimodal screening program that incorporates these biomarkers to detect and subsequently differentiate benign from malignant ovarian tumors.

Purpose To evaluate the impact of letrozole compared with placebo after adjuvant tamoxifen on quality of life (QOL) in the MA.17 trial. Methods Patients completed the Short Form 36-item Health Survey (SF-36) and the Menopause Specific Quality of Life Questionnaire (MENQOL) at baseline, 6 months, and annually. Mean change scores from baseline were compared between groups for summary measures and domains. A response analysis compared the proportion of patients who demonstrated an important change in QOL. Results Of 5,187 randomly assigned women in the trial, 3,612 (69.9%) participated in the QOL substudy: 1,799 were allocated to placebo and 1,813 were allocated to letrozole. No differences were seen between groups in mean change scores from baseline for the SF-36 physical and mental component summary scores at 6, 12, 24, and 36 months. Small (< 0.2 standard deviations) but statistically significant differences in mean change scores from baseline were seen for the SF-36 domains of physical functioning (12 months), bodily pain (6 months) and vitality (6 and 12 months), and the MENQOL vasomotor (6, 12, and 24 months) and sexual domains (12 and 24 months). On the response analysis, a significant difference was seen between groups for the bodily pain domain (percentage of patients reporting a worsening of QOL, 47% placebo v 51% letrozole; P = .009) and the vasomotor domain (22% placebo v 29% letrozole; P = .001). Conclusion Letrozole did not have an adverse impact on overall QOL. Small effects were seen in some domains consistent with a minority of patients experiencing changes in QOL compatible with a reduction in estrogen synthesis.

Recent experimental studies suggest C-reactive protein (CRP) may be a potential mediator of atherosclerosis and its complications. However, there is growing criticism of in vitro CRP studies that use commercial CRP preparations containing biologically active contaminants. The effects of commercial CRP, dialyzed commercial CRP (dCRP) to remove azide, and sodium azide (NaN 3 ) alone at equivalent concentrations to the undialyzed preparation were tested at varying concentrations on human umbilical vein endothelial cells (HUVEC), circulating endothelial outgrowth cells (EOC), and endothelial progenitor cells (EPC) in vitro. CRP and NaN 3 alone exhibited equivalent concentration-dependent, proapoptotic effects on HUVEC, EOC, and EPC ( P <0.01 versus control), whereas dCRP had no such effect. Similarly, CRP and NaN 3 alone caused equivalent concentration-dependent decreases in migration, proliferation, and matrigel tube formation ( P <0.01 versus control) in EOC and HUVEC, whereas dCRP had absolutely no effect on these biological functions at any of the concentrations used. We conclude that proapoptotic, antiproliferative, antimigratory, and antiangiogenic effects of this commercial CRP preparation on a number of endothelial cell phenotypes in culture may be explained by the presence of sodium azide in this preparation. This study has implications for interpretation of in vitro studies using CRP preparations containing azide at equivalent or higher concentrations.

Healthy older men manifest concomitant hypoandrogenemia and attenuation of LH pulse size. Because exogenous GnRH remains effective, a plausible intuition is that aging reduces hypothalamic GnRH secretion, thus mediating relative hypogonadotropic hypogonadism. To assess the impact of age on central GnRH outflow indirectly, we quantitated graded suppression of pulsatile LH secretion by saline and escalating doses of a potent and selective GnRH-receptor antagonist, ganirelix, in 18 healthy men ages 23–72 yr. The rationale is that ganirelix should reduce the amplitude of LH pulses in proportion to both drug concentration and endogenous GnRH feedforward. To this end, blood was sampled every 10 min for 2 h before and 16 h after sc administration of saline or ganirelix and for 3 additional hours after iv injection of a fixed dose of GnRH (100 ng/kg); concentrations of LH and ganirelix were measured by immunochemiluminometry and RIA, respectively; and pulsatile LH secretion was quantitated by a deconvolution procedure. Log-linear regression analysis was used to estimate the sensitivity of pulsatile LH secretion to inhibition by a unit increase in serum ganirelix concentrations in each subject. Statistical analyses revealed that increasing age markedly attenuated the capability of ganirelix to decrease LH pulse size (viz., r = −0.648; P = 0.004). In contrast, age did not modify the competitive interaction between injected GnRH and ganirelix. These joint outcomes support the clinical hypothesis that age diminishes hypothalamic GnRH outflow without impairing GnRH action in healthy men.

The inverse problem of determining the size, shape and orientation of a submerged object using the scattered field data is studied. Based on the physical optics approximate, the profile function of the object is found directly proportional to its ramp response that is the second integral of the impulse response. Through analyzing the feature of the ramp response in different computed frequency ranges, it is found that the low-frequency data are essential to the shape of the underwater object while the high-frequency data are very important to the size of the object. Therefore, when employing the high-frequency data to compute the ramp response, the edge of the object can only be highlighted in the illuminated region at certain aspect. Based on this finding, a new method is developed to estimate the size of underwater objects. The present method uses different frequency ranges to determine different parameters of the underwater objects so as to achieve the best accuracy. A number of examples are presented to demonstrate the effectiveness of the present method in using the ramp response technique to identify the size of both rigid and elastic bodies.

Recent evidence suggests that alveolar epithelial cells (AECs) may contribute to the development, propagation, and resolution of acute lung injury (ALI)/acute respiratory distress syndrome (ARDS). Proinflammatory cytokines, pathogen products, and injurious mechanical ventilation are important contributors of excessive inflammatory responses in the lung. In the present study, we used cDNA microarrays to define the gene expression patterns of A549 cells (an AEC line) in the early stages of three models of pulmonary parenchymal cell activation: cells treated with tumor necrosis factor-α (TNFα) (20 ng/ml), lipopolysaccharide (LPS, 1 μg/ml), or cyclic stretch (20% elongation) for either 1 h or 4 h. Differential gene expression profiles were determined by gene array analysis. TNFα induced an inflammatory response pattern, including induction of genes for chemokines, inflammatory mediators, and cell surface membrane proteins. TNFα also increased genes related to pro- and anti-apoptotic proteins, signal transduction proteins, and transcriptional factors. TNFα further induced a group of genes that may form a negative feedback loop to silence the NFκB pathway. Stimulation of AECs with mechanical stretch changed cell morphology and activated Src protein tyrosine kinase. The combination of TNFα plus stretch enhanced or attenuated expression of multiple genes. LPS decreased microfilament polymerization but had less impact on NFκB translocation and gene expression. Results from this study indicate that AECs can tailor their response to different stimuli or/and combination of stimuli and subsequently play an important role in acute inflammatory responses in the lung.