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The article discusses a study on the role of microRibonucleic acid (miRNA) in ovarian cancer and the effect of genistein treatment. It states that miRNA's role is well established due to its function in cell differentiation, proliferation and cell cycle control. Cell lines were and microRNA profiling was done in untreated and genistein-treated cells. Estrogen receptors were studied using polymerase chain reaction and Western immunoblotting. The study found and detected miRNA in both cell lines.

Many health professions include written examinations among their licensing procedures, and constructing these examinations poses special difficulties. For physician licensure the central dilemma is manifested by the longstanding tradition of undifferentiated licensure contrasting with the strong specialty orientation of contemporary physician training. This article details the authors' response to this problem and describes the resulting design of a new physician licensure examination. Using a combination of empirical data and expert judgment, descriptions of selected clinical encounters have been assembled as a practice model of a physician licensed for the delivery of general health care of patients. Application of an explicitly situational framework to the design of a physician licensure examination is unusual, and the approach is advocated for use with other health professions. [ABSTRACT FROM AUTHOR]

Problem: One immunoregulatory pathway that has received little attention is placental exosome release. In normal pregnancy, as factors linked with early immunomodulation decline, placental exosomes become key in modulating T-cell activation, maintaining the absence of effector T-cells by enhancing T cell apoptosis and loss of CD3-z. Method of Study: Placental exosomes were isolated from the maternal peripheral circulation by a chromatographic/MACS procedure developed to specifically purify exosomes of placental origin. Exosomal FasL was identified by immunoelectron microscopy (IEM) and quantified by ELISA. Exosomal suppression of T cell signaling molecules and induction of apoptosis was determined by flow cytometry and DNA fragmentation, respectively. The role of FasL in these events was defined by use of FasL blocking antibody. The differential effect of exosomes on CD3-z on T subsets was analyzed by western immunoblot (WB). Results: When T cells were co-incubated with placental exosomes, CD3-z was down-regulated, with placental exosomes treated cells expressing 18,900 ± 7,000 MESF units of zeta, while control fraction-treated cells expressed 49,000 ± 4,800 MESF units of zeta ( P < 0.001). This down-regulation of CD3-z was partially reversed by pre-incubating T cells with ZB4 antibody, suggesting a role for FasL. IEM revealed FasL-antibody complexes located on the exterior of placental exosomes; however, only 20/27 preparations were FasL+. When placental exosomes were added to T cells, the level of CD3-z expression on CD8+ cells was 7.1%, (8.7% vs 59.7%) inhibited 1.43-fold more than in CD4+ cells (85.5 P < 0.01). On CD4+CD25+ cells, CD3-z was not significantly inhibited. ( P < 0.05). Conclusions: While all term placental exosome preparations tested induced apoptosis, exosomes obtained from 7/27 patients were negative for FasL but were able to induce DNA degradation. These results indicate that, while exosomal FasL is apoptogenic, additional exosome components are capable of inducing apoptosis, but these factors exhibit differential effect on T subsets. [ABSTRACT FROM AUTHOR]

Objective: To investigate TCR-CD3zeta expression by cultured T lymphocytes exposed to midtrimester sera from pregnant women in whom preeclampsia developed at term compared with normotensive pregnant control subjects., Study Design: Sera obtained at 24 to 28 weeks' gestation from 16 nulliparous women in whom preeclampsia developed at term and from 32 gestational age-matched control subjects without preeclampsia were evaluated for TCR-CD3zeta chain expression with use of Jurkat cells. Subsets of serum samples from 6 women with preeclampsia and 6 control subjects were then evaluated for their ability to induce apoptosis and to suppress interleukin-2 production. Groups were compared by use of the Kruskal-Wallis test, and P <.05 was considered significant., Results: TCR-CD3zeta chain expression in cultured T lymphocytes was suppressed in approximately 60% of untreated control subjects after incubation with sera from normotensive pregnant women compared with 30% after incubation with sera from women with preeclampsia (P <.001). T-cell apoptosis was significantly higher after incubation with sera from normotensive control subjects, as was the expression of the proapoptotic regulator Bax, compared with sera from women with preeclampsia. Interleukin-2 levels were higher in T cells incubated with sera from women in whom preeclampsia later developed compared with sera from normotensive pregnant women (27.7 ng/mL versus 72.5 ng/mL; P <.001)., Conclusions: Nulliparous women in whom preeclampsia developed did not suppress TCR-CD3zeta levels to the extent of normotensive control subjects, which may be linked to decreased lymphocyte apoptosis. This occurs remotely from the manifestation of clinical disease and suggests a deficiency in a serum factor in preeclampsia that may induce T cell zeta chain suppression in normal pregnancy.

Objectives: To compare limb-load distribution between horses with and without acute or chronic laminitis., Animals: 10 horses with carbohydrate-induced acute laminitis, 20 horses with naturally occurring chronic laminitis, and 20 horses without foot abnormalities (controls)., Procedures: Limb-load distribution was determined, using a custom-designed system that allowed simultaneous quantification of the mean percentage of body weight voluntarily placed on each limb (ie, mean limb load) and the SD of the mean load over a 5-minute period (ie, load distribution profile [LDP]). Load distribution profile was used as an index of frequency of load redistribution., Results: Mean loads on fore- and hind limbs in control horses were 58 and 42%, respectively, and loads were equally and normally distributed between left and right limbs. In addition, forelimb LDP was greater, compared with hind limbs, and was affected by head and neck movement. In comparison, limb-load distribution in horses with chronic laminitis was characterized by an increase in the preferential loading of a forelimb, a decrease in total forelimb load, and an increase in LDP that was correlated with severity of lameness. In horses with carbohydrate-induced acute laminitis, mean limb loads after onset of lameness were not different from those prior to lameness; however, LDP was significantly decreased after onset of lameness., Conclusion and Clinical Relevance: Quantification of limb-load distribution may be an applicable screening method for detecting acute laminitis, grading severity of lameness, and monitoring rehabilitation of horses with chronic laminitis.

We analyzed clonal populations of ovarian cancer cells for heterogeneity in p53 mutations (exons 4-9) and chemosensitivity. UL-3A cells were developed from a patient with stage IIIC ovarian adenocarcinoma. Heterogeneity in p53 mutations was demonstrated, ranging from point mutations to deletions in exons 4, 6 and 7. UL-3A cells contained two point mutations, in codon 248 of exon 7 and in codon 76 of exon 4. Five groups of clones were identified according to the p53 mutations. UL-3A clones with low p53 levels were more sensitive to CDDP (LD50 <8.0 microg/ml). Heterogeneity of p53 mutations may provide growth advantage during disease progression or chemotherapy.

Background: Drug sensitivity testing (DST) is used to predict the clinical response to chemotherapy with limited success. Our objective was to evaluate assays that measure cell proliferation or apoptosis in determining sensitivity of ovarian cancer cells to cisplatin and paclitaxel., Materials and Methods: Four ovarian cancer lines were used. LD10-LD90 doses were determined by viability assays. Assays measuring cell proliferation, sulforhodamine-B (SRB), tritiated thymidine; and cell death, diphenylamine or DNA histone ELISA were compared., Results: SRB assay was consistent and sensitive. Histone ELISA correlated with the viability assay at high doses. The [3H] thymidine test was not sensitive and resulted in false positive responses. While less sensitive, detection of apoptosis by diphenylamine assay shows a similar trend to histone ELISA., Conclusions: We demonstrate significant differences between the various assays. Most of these assays are better predictors of resistance. Further studies are needed to determine the best correlation between in vitro testing and responses in vivo.

Objective: This study analyzed a model for the identification of specific epitopes recognized by autologous tumor-reactive humoral responses of endometrial cancer patients as potential markers for the monitoring of cancer., Methods: The presence of circulating pro- and mature forms of cathepsin D and antibodies reactive with this enzyme were identified by Western immunoblot and quantitated by an enzyme immunoassay. Specific immunoreactivities with 34- and 52-kDa cathepsin D forms were analyzed by Western immunoblot using sera from endometrial cancer patients (n = 40) and normal volunteers (n = 15). Subsequently, reactivities with specific cathepsin D epitopes were defined by a peptide-specific ELISA., Results: Circulating pro-forms of cathepsin D were detected in 31 of 40 endometrial cancer patients tested and none of the control volunteers. Circulating IgG reactive with cathepsin D could be demonstrated in 29/31 patients with circulating procathepsin D, while an anti-cathepsin D response was not detectable in normal controls. This response appeared to be directed against the pro-peptide portion of cathepsin D. Using a peptide-specific ELISA, the frequencies of antibody production against specific epitopes within the pro-peptide were defined., Conclusion: There is a demonstrable tumor-reactive immune response elicited in endometrial cancer patients, directed against specific antigenic epitopes, some of which are conserved among these patients. Since these proteins are recognized as non-self, due at least in part to posttranslational processing errors, defining these epitopes will be useful as a means of diagnosis, assessment of therapeutic success, and, ultimately, identification of immunotherapeutic targets., (Copyright 2001 Academic Press.)