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The superordinate principles governing the transcriptome response of differentiating cells exposed to drugs are still unclear. Often, it is assumed that toxicogenomics data reflect the immediate mode of action (MoA) of drugs. Alternatively, transcriptome changes could describe altered differentiation states as indirect consequence of drug exposure. We used here the developmental toxicants valproate and trichostatin A to address this question. Neurally differentiating human embryonic stem cells were treated for 6 days. Histone acetylation (primary MoA) increased quickly and returned to baseline after 48 h. Histone H3 lysine methylation at the promoter of the neurodevelopmental regulators PAX6 or OTX2 was increasingly altered over time. Methylation changes remained persistent and correlated with neurodevelopmental defects and with effects on PAX6 gene expression, also when the drug was washed out after 3-4 days. We hypothesized that drug exposures altering only acetylation would lead to reversible transcriptome changes (indicating MoA), and challenges that altered methylation would lead to irreversible developmental disturbances. Data from pulse-chase experiments corroborated this assumption. Short drug treatment triggered reversible transcriptome changes; longer exposure disrupted neurodevelopment. The disturbed differentiation was reflected by an altered transcriptome pattern, and the observed changes were similar when the drug was washed out during the last 48 h. We conclude that transcriptome data after prolonged chemical stress of differentiating cells mainly reflect the altered developmental stage of the model system and not the drug MoA. We suggest that brief exposures, followed by immediate analysis, are more suitable for information on immediate drug responses and the toxicity MoA.

Information on design principles governing transcriptome changes upon transition from safe to hazardous drug concentrations or from tolerated to cytotoxic drug levels are important for the application of toxicogenomics data in developmental toxicology. Here, we tested the effect of eight concentrations of valproic acid (VPA; 25-1000 μM) in an assay that recapitulates the development of human embryonic stem cells to neuroectoderm. Cells were exposed to the drug during the entire differentiation process, and the number of differentially regulated genes increased continuously over the concentration range from zero to about 3000. We identified overrepresented transcription factor binding sites (TFBS) as well as superordinate cell biological processes, and we developed a gene ontology (GO) activation profiler, as well as a two-dimensional teratogenicity index. Analysis of the transcriptome data set by the above biostatistical and systems biology approaches yielded the following insights: (i) tolerated (≤25 μM), deregulated/teratogenic (150-550 μM), and cytotoxic (≥800 μM) concentrations could be differentiated. (ii) Biological signatures related to the mode of action of VPA, such as protein acetylation, developmental changes, and cell migration, emerged from the teratogenic concentrations range. (iii) Cytotoxicity was not accompanied by signatures of newly emerging canonical cell death/stress indicators, but by catabolism and decreased expression of cell cycle associated genes. (iv) Most, but not all of the GO groups and TFBS seen at the highest concentrations were already overrepresented at 350-450 μM. (v) The teratogenicity index reflected this behavior, and thus differed strongly from cytotoxicity. Our findings suggest the use of the highest noncytotoxic drug concentration for gene array toxicogenomics studies, as higher concentrations possibly yield wrong information on the mode of action, and lower drug levels result in decreased gene expression changes and thus a reduced power of the study.

Endometrial carcinoma differential 3 (EDI3) was the first member of the glycerophosphodiesterase (GDE) protein family shown to be associated with cancer. Our initial work demonstrated that endometrial and ovarian cancer patients with primary tumors overexpressing EDI3 had a higher risk of developing metastasis and decreased survival. Further analysis indicated that EDI3 cleaves glycerophosphocholine to choline and glycerol-3-phosphate, increases the levels of active PKC, and enhances the migratory activity of tumor cells. Despite these initial findings, EDI3 remained mainly uncharacterized. Therefore, to obtain an overview of processes in which EDI3 may be involved, gene array analysis was performed using MCF-7 breast cancer cells after EDI3 knockdown compared with a non-targeting control siRNA. Several biological motifs were altered, including an enrichment of genes involved in integrin-mediated signaling. More specifically, silencing of EDI3 in MCF-7 and OVCAR-3 cells was associated with reduced expression of the key receptor subunit integrin β1, leading to decreased cell attachment and spreading accompanied by delayed formation of cell protrusions. To confirm these results, we stably overexpressed EDI3 in MCF-7 cells which led to elevated integrin β1 expression associated with enhanced cell attachment and spreading - two processes critical for metastasis. In conclusion, our data provide further insight into the role of EDI3 during cancer progression.

Developmental neurotoxicity (DNT) and many forms of reproductive toxicity (RT) often manifest themselves in functional deficits that are not necessarily based on cell death, but rather on minor changes relating to cell differentiation or communication. The fields of DNT/RT would greatly benefit from in vitro tests that allow the identification of toxicant-induced changes of the cellular proteostasis, or of its underlying transcriptome network. Therefore, the 'human embryonic stem cell (hESC)-derived novel alternative test systems (ESNATS)' European commission research project established RT tests based on defined differentiation protocols of hESC and their progeny. Valproic acid (VPA) and methylmercury (MeHg) were used as positive control compounds to address the following fundamental questions: (1) Does transcriptome analysis allow discrimination of the two compounds? (2) How does analysis of enriched transcription factor binding sites (TFBS) and of individual probe sets (PS) distinguish between test systems? (3) Can batch effects be controlled? (4) How many DNA microarrays are needed? (5) Is the highest non-cytotoxic concentration optimal and relevant for the study of transcriptome changes? VPA triggered vast transcriptional changes, whereas MeHg altered fewer transcripts. To attenuate batch effects, analysis has been focused on the 500 PS with highest variability. The test systems differed significantly in their responses (<20 % overlap). Moreover, within one test system, little overlap between the PS changed by the two compounds has been observed. However, using TFBS enrichment, a relatively large 'common response' to VPA and MeHg could be distinguished from 'compound-specific' responses. In conclusion, the ESNATS assay battery allows classification of human DNT/RT toxicants on the basis of their transcriptome profiles.

BACKGROUND: There has been minimal research on the influence of delays for cancer treatments on patient outcomes. We measured the influence of delays to nonemergent colon cancer surgery on operative mortality, disease-specific survival and overall survival. METHODS: We used the linked Surveillance, Epidemiology and End Results (SEER)-Medicare databases (1993-1996) to identify patients who underwent nonemergent colon cancer surgery. We assessed 2 time intervals: surgeon consult to hospital admission for surgery and first diagnostic test for colon cancer to hospital admission. Follow-up data were available to the end of 2003. We selected the time intervals to create patient groups with clinical relevance and they did not extend past 120 days. RESULTS: We identified 7989 patients who underwent nonemergent colon cancer surgery. Median delays from surgeon consult to admission and from first diagnostic test to admission were 7 and 17 days, respectively. The odds of operative mortality were similar if the consult-to-admission interval was 22 days or more versus 1-7 days (odds ratio [OR] 1.0, 95% confidence interval [CI] 0.6-1.8, p = 0.91) or if the test-to-admission interval was 43 days or more versus 1-14 days (OR 0.8, 95% CI 0.4-1.5, p = 0.51), respectively. For these same respective interval comparisons, disease-specific survival was not influenced by the consult-to-admission wait (hazard ratio [HR] 1.0, 95% CI 0.9-1.2, p = 0.91) or the test-to-admission wait (HR 1.0, 95% CI 0.8-1.1, p = 0.63). The risk of death was slightly greater if the consult-to-admission interval was 22 or more days versus 1-7 days (HR 1.1, 95% CI 1.0-1.2, p = 0.013) and if the test-to-admission interval was 43 days or more versus 1-14 days (HR 1.2, 95% CI 1.1-1.3, p = 0.003). CONCLUSION: It is unlikely that delays to nonemergent colon cancer surgery longer than 3 weeks from initial surgical consult or longer than 6 weeks from first diagnostic test negatively impact operative mortality, disease-specific survival or overall survival.

Background: Previous reports of liver resection for metastatic colorectal cancer (CRC) are typically from single centers and cannot account for selection or referral bias. We measured longterm survival after liver resection for metastatic CRC in the province of Ontario, Canada (population 12 million)., Study Design: The Ontario Cancer Registry is an administrative database that links all hospital records, pathology reports, and vital statistics for patients with a diagnosis of cancer. We used the Registry to identify and obtain information on all patients who underwent liver resection for metastatic CRC in calendar years 1996 to 2004. Pathology reports of the original CRC resection and subsequent liver resections were individually reviewed., Results: Eight hundred forty-one resections were performed at 43 centers across Ontario during the 9-year period, including wedge resection (n = 303; 36%); lobectomy (n = 466; 55%); and trisectionectomy (n = 72; 9%). Ninety-one percent and 54% of resections were performed at teaching and high-volume centers (> 80 resections), respectively. Most liver resections were performed more than 120 days after original CRC operation (672 of 841; 80%). Perioperative mortality was 3%. Unadjusted 1-, 3-, and 5-year survival after liver resection was 88%, 59%, and 43%, respectively. Survival was improved when resection was performed for fewer than 2 tumor nodules, at high-volume centers, or in the years 2001 to 2004., Conclusions: Results in this population-based series are consistent with those of single-hospital series assessing longterm survival after liver resection for metastatic CRC. These findings support continued efforts to aggressively identify and resect CRC liver metastases.

Background and Objectives: This study assessed lymph node counts, lymph node status (positive or negative), and survival among patients undergoing colon cancer surgery in Ontario, Canada., Methods: We obtained data from the Ontario Cancer Registry on 960 patients who underwent a major colon cancer resection in years 1991-1993. Patients and hospitals were ranked by lymph node count to correlate lymph node counts and lymph node status. For node-negative patients we assessed the influence of patient, hospital, and tumor factors on lymph node counts and survival., Results: The rate of node-positive patients was similar among the lymph node count groups. For example, the odds ratio of a patient being node positive if the lymph node count was 10-36 versus 1-3 was 1.0 (CI 0.6-1.6, P = 0.42). Among node-negative patients, survival was improved for patients with a high (10-36) versus low (1-3) lymph node count (HR 0.6, CI 0.4-1.0, P = 0.03). No patient, hospital, or tumor factors predicted both a higher lymph node count and improved survival., Conclusions: In this population-based study of patients undergoing colon cancer surgery, higher lymph node counts did not correlate with increased rates of node-positive status., (Copyright 2006 Wiley-Liss, Inc.)

To evaluate the level of U. urealyticum colonization of female urogenital tract, the method of the multiplex polymerase chain reaction (PCR) in the presence of two pairs of primers, corresponding to genes controlling U. urealyticum 16S rRNA and unique human osteopontin was used. The study of 93 clinical specimens showed no correlation between high colonization level and the presence of definite clinical manifestations of U. urealyticum infection. The determination of ureaplasmic biovars was carried out by the method of PCR in the presence of 3 primers corresponding to the multiple-banded antigen (MBA) gene. Biovar parvo was detected in 85% of the specimens, biovar T960 in 11% and both biovars were detected in 4% of the specimens. The biovar distribution in the groups of women with different clinical symptoms was approximately similar. U. urealyticum of biovar T960 occurred more frequently (33% of the specimens) only in a group of women with vaginal discharge characteristic of inflammation.

The comparative evaluation of the PCR test "Polimik" (Research and Production Firm "Litekh", Moscow) and the PCR test of the Novosibirsk Institute of Bioorganic Chemistry (NIBC) was carried out. The results obtained with the use of the PCR test "Polimik" and the PCR test of the NIBC of the detection of C. trachomatis and M. hominis coincided in 97.8% and 97.4% of cases. For U. urealyticum, the coincidence of the results of both PCR tests was 81.2%. Among women who visited gynecologists for reproductive function disturbances, the use of the PCR tests made it possible to detect C. trachomatis in 19 (5.5%) out of 343 cases, U. urealyticum in 96 (39.0%) out of 246 cases and M. hominis in 25 (16.9%) out of 148 cases. The results of the investigation revealed that the occurrence of C. trachomatis infection in Novosibirsk was comparable with that in other regions of the world among the low-risk groups of the population. The detection frequency of M. hominis and U. urealyticum with the use of the PCR tests showed that the occurrence of infections caused by these causative agents coincided with the data obtained in other countries.

Nursing supervisors hear certain complaints from nurses with unusual frequency. In this article, seven common complaints are presented, and an example demonstrating each complaint is described. The obvious and not-so-obvious reasons behind each complaint are analysed, and suggestions made for supervisory behaviour which will reduce the likelihood of such complaints. When nursing supervisors actively pursue good managerial practices, the frequency of complaints will decline, interpersonal relations will improve, and increased supervisory effectiveness will result.

When nurses get involved in nursing administration, they may experience difficulties with the managerial role. There are several reasons why these difficulties occur: failure to recognize that the skills required for management are different than those required for nursing; refusing to "let go" of former nursing duties; inconsistent emphasis on the development of managerial capability among nursing supervisors; and insufficient formal training in management. Suggestions for making the transition to management easier are presented. These include developing the proper mix of skills for management; delegating authority properly; systematizing on-the-job-training for supervisors; and restructuring the formal academic preparation that nurses receive while in B.N. programs.

When attempts are made to improve organizational performance, both rational and emotional factors will have to be recognized. One of the important emotional factors is the tendency of people to behave politically while they are carrying out their assigned duties. The meaning and importance of organizational politics is discussed, and several typical reactions of nurse administrators to organizational politics are examined. Practical suggestions are made to help nurse administrators develop greater political sensitivity and deal effectively with political behavior.

Streptozotocin induced diabetes mellitus in 4 out of 6 male rats. On the other hand, all 6 drug-injected animals had decreased serum testosterone values. The Leydig cells from 6 control rats and all streptozotocin-injected animals were characterized by moderate numbers of mitochondria, few lipid droplets, and an abundance of smooth surfaced endoplasmic reticulum. Quantitative analysis of numbers of mitochondria and lipid droplets revealed no differences between control and streptozotocin-injected animals. However, there were smaller mitochondria, larger lipid droplets and a trend toward fewer cells with dilated profiles of smooth endoplasmic reticulum in all drug injected animals. These cytological and biochemical findings suggest that diabetes per se had little direct effect on Leydig cell function. However, taken together with previous studies, these observations suggest that streptozotocin may directly affect the hypothalamo-pituitary-testicular axis possibly at the level of LHRH-secreting neurons of the hypothalamus.