0591 The Significance of Body Mass Index in Varying Sleep Apnea Levels for Men and Women

Introduction

A BMI increase, in men and women, is associated with an increased severity and progression of OSA. This study will examine the impact of BMI on varying levels of OSA severity and progression.

Methods

Participants, divided by sex, included 2728 (47%) men and 3076 (53%) women over the age of 40 that were in the Sleep Heart Health Study (SHHS). Participants were separated into 1 of 10 groups based on initial OSA levels at SHHS time point 1 (SHHS1) and ending OSA levels at SHHS time point 2 (SHHS2) as measured by RDI. A Kruskall-Wallis test examined the BMI median differences in the groups. Post-hoc tests, including pairwise comparisons and Wilcoxon rank sum test with Holm adjustment, were conducted to further examine results.

Results

Significant differences existed between certain groups (Men: Chi-Square=146.87, p<.001, df=9; Women: Chi-Square=128.59, p<.001, df=9). For men and women, those in the group with normal OSA levels at SHHS1 and SHHS2 had significant BMI differences compared to those in all 9 other groups where mild, moderate, or severe OSA levels exist at SHHS1 or SHHS2. Additionally, in men, BMI is significantly different for those with normal or mild OSA levels at SHHS2 compared to those with moderate or severe OSA levels at SHHS2. Also, a significant BMI difference exists in men maintaining mild OSA levels throughout SHHS compared to those maintaining severe OSA levels.

Conclusion

Although BMI is a known influential factor in OSA progression, this study demonstrated that those maintaining normal OSA levels over time have a significant BMI difference compared to those reaching even mild OSA levels over time. Additional implications were also found for men. These findings may coincide with recent research suggesting that one needs to progress only to moderate OSA levels to reach a tipping point of significantly increasing and impacting many health risks.

Support

Robert Wood Johnson Foundation Future of Nursing Scholars Program

Acute Toxicity of Acrylonitrile: Effect of Diet on Tissue Nonprotein Sulfhydryl Content and Distribution of 1–14C-Acrylonitrile or Its Metabolites

The influence of diet on the acute toxicity (lethality) and distribution of glutathione as measured by tissue nonprotein sulfhydryl (NPSH) concentration following acrylonitrile (ACN) treatment was studied. The tissue distribution of radiolabeled (14C) acrylonitrile or its radioactive metabolites was also determined. The diets tested were a standard laboratory rat chow; a casein-based, complete diet; and 2 diets high in saturated fat content that were either lipotrope deficient or lipotrope supplemented. The latter 2 diets were associated with decreased weight gain in the absence of ACN and increased lethality after orally administratered ACN. The increase in lethality, while most pronounced in the group fed the lipotrope-deficient, high-fat diet, was also seen in rats fed the purified control diet. The high-fat diets were associated with increases in brain and liver NPSH concentrations (mg NPSH/100 g body weight). Following oral administration of 1–14C-ACN, blood contained the highest specific activity. In terms of fraction of administered dose, liver was found to contain the highest total fraction. In the tissues measured, a majority of radioactivity appeared bound to trichloroacetic acid (TCA) insoluble components. The sequence of tissue activity (nCi 14C per g or ml) was as follows: blood > stomach > liver, duodenum, lung, kidney > brain > adrenal. While diet affected toxicity, it did not modify this general ranking.

A safety assessment of branched chain saturated alcohols when used as fragrance ingredients

The Branched Chain Saturated Alcohol (BCSA) group of fragrance ingredients was evaluated for safety. In humans, no evidence of skin irritation was found at concentrations of 2-10%. Undiluted, 11 materials evaluated caused moderate to severe eye irritation. As current end product use levels are between 0.001% and 1.7%, eye irritation is not a concern. The materials have no or low sensitizing potential. For individuals who are already sensitized, an elicitation reaction is possible. Due to lack of UVA/UVB light-absorbing structures, and review of phototoxic/photoallergy data, the BCSA are not expected to elicit phototoxicity or photoallergy. The 15 materials tested have a low order of acute toxicity. Following repeated application, seven BCSA tested were of low systemic toxicity. Studies performed on eight BCSA and three metabolites show no in vivo or in vitro genotoxicity. A valid carcinogenicity study showed that 2-ethyl-1-hexanol is a weak inducer of liver tumors in female mice, however, the relevance of this effect and mode of action to humans is still a matter of debate. The Panel is of the opinion that there are no safety concerns regarding BCSA under the present levels of use and exposure.

Role of registered nurses in error prevention, discovery and correction

BACKGROUND

Registered nurses have a vital role in discovering and correcting medical error.

OBJECTIVE

To describe the type and frequency of errors detected by American critical care nurses, and to ascertain who made the errors discovered by study participants.

METHODS

Daily logbooks were used to collect information about errors discovered by a random sample of 502 critical care nurses during a 28-day period.

RESULTS

Although the majority of errors discovered and corrected by critical care nurses involved medications (163/367), procedural errors were common (n = 115). Charting and transcription errors were less frequently discovered. The errors discovered by participants were attributed to a wide variety of staff members including nurses, doctors, pharmacists, technicians and unit secretaries.

CONCLUSIONS

Given the importance of nurses in maintaining patient safety, future studies should identify factors that enhance their effectiveness to prevent, intercept and correct healthcare errors.

A toxicologic and dermatologic assessment of cyclic acetates when used as fragrance ingredients

An evaluation and review of a structurally related group of fragrance materials.

The Experience of Hot Flushes After Breast Cancer

As survival from breast cancer increases, there is a corresponding rise in the number of women living with the long-term consequences of its treatment. Distressing menopausal hot flushes occur in many of these women. This article reports on interviews conducted with 8 women, exploring the experience of hot flushes after breast cancer. Women's accounts of hot flushes varied from being a mild sensation to an intensely unpleasant sensation affecting the whole body and accompanied by drenching perspiration. Flushes affected all aspects of the women's lives, including sleeping, clothing, social situations, intimate relationships, and ability to work. Emotionally, women talked about being out of control. Having cancer and menopause simultaneously made it more difficult for the women to cope, and cancer treatment could cause flushing. The women used many strategies to help relieve their difficulties. Some resorted to hormone replacement therapy, whereas others turned to herbal medications and other alternative interventions such as acupuncture. Most women adopted behavioral strategies to try to regain control. Ultimately, they found that control was gained by attitude of mind. Cognitive behavioral techniques may enhance the sense of control and contribute to coping during hot flushes.

In situ evaluation of residual breast tumor and tumor grade using medical hyperspectral imaging (MHSI)

10677

Background: MHSI is a camera-based technique providing spectral data regarding tissue chemistry for each pixel in an image. Over 30% of women suffer local recurrence after resection. Intraoperative assessment of residual tumor & tumor grade would optimize care. Methods: We studied 42 S-D rats w/ breast tumors induced by gavage of DMBA & 15 controls. Tumors were exposed & resected, intentionally leaving ∼1mm residual tumor pieces. Gross examination, histo-pathology & MHSI (total 335) were performed for tumors, tumor beds after partial and total resection & control sites. A visible light MHSI system (HyperMed,Waltham, MA) w/ 40μm resolution & algorithms based on spectral features of the surgical field were developed and implemented for this study. Gross observation at surgery represents truth, as small tumor pieces were left intentionally by the surgeon and recorded. Samples from tumor beds were collected and histopathologically analyzed. When seen, gross tumor was removed from tumor bed by the pathologist. Results: MHSI performed well at identifying tumor. The kappa statistic(κ) for gross vs MHSI (84%) is significantly higher than κ for gross vs histopathology (76%) where for the κ the estimated asymptotic standard error is 3%. MHSI associates more strongly with gross than histopathology does. 81 tissue samples were separated into histologic grade: 0 = normal, 1 = benign tumor, 2 = intraductal Ca, 3 = papillary & cribiform Ca, 4 = papillary & cribiform Ca with invasion &/or comedo Ca. The imaging team (blinded) assigned tumor grade to each MHSI image. Statistical analysis defined 3 histologic groups: 9 normal (grade 0) tissue, 18 benign & intraductal tumors (grades 1–2), 54 advanced tumors (papillary, cribiform with invasion/comedo Ca, grades 3–4). Both histopathology & MHSI identified all 9 normal samples. Of 18 samples in group 2 (benign/intraductal by histopathology), 17 were qualified as benign/intraductal by MHSI (94% sens) & 1 as advanced. Of 54 samples with adv tumors by histopathology, MHSI identified 48 (89% sens) as advanced & 6 as intraductal. Conclusions: MHSI may provide convenient intraoperative, near real-time images with useful data about residual tumor & tumor grade. Human trials are planned.

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A randomised controlled trial to assess the effectiveness and cost of a patient orientated self management approach to chronic inflammatory bowel disease

OBJECTIVES

We developed a patient centred approach to chronic disease self management by providing information designed to promote patient choice. We then conducted a randomised controlled trial of the approach in inflammatory bowel disease (IBD) to assess whether it could alter clinical outcome and affect health service use.

DESIGN

A multicentre cluster randomised controlled trial.

SETTING

The trial was conducted in the outpatient departments of 19 hospitals with randomisation by treatment centre, 10 control sites, and nine intervention sites. For patients at intervention sites, an individual self management plan was negotiated and written information provided.

PARTICIPANTS

A total of 700 patients with established inflammatory bowel disease were recruited.

MAIN OUTCOME MEASURES

Main outcome measures recorded at one year were: quality of life, health service resource use, and patient satisfaction. Secondary outcomes included measures of enablement-confidence to cope with the condition.

RESULTS

One year following the intervention, self managing patients had made fewer hospital visits (difference -1.04 (95% confidence interval (CI) -1.43 to -0.65); p<0.001) without increase in the number of primary care visits, and quality of life was maintained without evidence of anxiety about the programme. The two groups were similar with respect to satisfaction with consultations. Immediately after the initial consultation, those who had undergone self management training reported greater confidence in being able to cope with their condition (difference 0.90 (95% CI 0.12-1.68); p<0.03).

CONCLUSIONS

Adoption of this approach for the management of chronic disease such as IBD in the NHS and other managed health care organisations would considerably reduce health provision costs and benefit disease control.

Safety assessment of allylalkoxybenzene derivatives used as flavouring substances - methyl eugenol and estragole

This publication is the seventh in a series of safety evaluations performed by the Expert Panel of the Flavor and Extract Manufacturers' Association (FEMA). In 1993, the Panel initiated a comprehensive program to re-evaluate the safety of more than 1700 GRAS flavouring substances under conditions of intended use. In this review, scientific data relevant to the safety evaluation of the allylalkoxybenzene derivatives methyl eugenol and estragole is critically evaluated by the FEMA Expert Panel. The hazard determination uses a mechanism-based approach in which production of the hepatotoxic sulfate conjugate of the 1'-hydroxy metabolite is used to interpret the pathological changes observed in different species of laboratory rodents in chronic and subchronic studies. In the risk evaluation, the effect of dose and metabolic activation on the production of the 1'-hydroxy metabolite in humans and laboratory animals is compared to assess the risk to humans from use of methyl eugenol and estragole as naturally occurring components of a traditional diet and as added flavouring substances. Both the qualitative and quantitative aspects of the molecular disposition of methyl eugenol and estragole and their associated toxicological sequelae have been relatively well defined from mammalian studies. Several studies have clearly established that the profiles of metabolism, metabolic activation, and covalent binding are dose dependent and that the relative importance diminishes markedly at low levels of exposure (i.e. these events are not linear with respect to dose). In particular, rodent studies show that these events are minimal probably in the dose range of 1-10 mg/kg body weight, which is approximately 100-1000 times the anticipated human exposure to these substances. For these reasons it is concluded that present exposure to methyl eugenol and estragole resulting from consumption of food, mainly spices and added as such, does not pose a significant cancer risk. Nevertheless, further studies are needed to define both the nature and implications of the dose-response curve in rats at low levels of exposure to methyl eugenol and estragole.

Green tea extracts decrease carcinogen-induced mammary tumor burden in rats and rate of breast cancer cell proliferation in culture

Epidemiological evidence suggests tea (Camellia sinensis L.) has chemopreventive effects against various tumors. Green tea contains many polyphenols, including epigallocatechin-3 gallate (EGCG), which possess anti-oxidant qualities. Reduction of chemically induced mammary gland carcinogenesis by green tea in a carcinogen-induced rat model has been suggested previously, but the results reported were not statistically significant. Here we have tested the effects of green tea on mammary tumorigenesis using the 7,12-dimethylbenz(a)anthracene (DMBA) Sprague-Dawley (S-D) rat model. We report that green tea significantly increased mean latency to first tumor, and reduced tumor burden and number of invasive tumors per tumor-bearing animal; although, it did not affect tumor number in the female rats. Furthermore, we show that proliferation and/or viability of cultured Hs578T and MDA-MB-231 estrogen receptor-negative breast cancer cell lines was reduced by EGCG treatment. Similar negative effects on proliferation were observed with the DMBA-transformed D3-1 cell line. Growth inhibition of Hs578T cells correlated with induction of p27(Kip1) cyclin-dependent kinase inhibitor (CKI) expression. Hs578T cells expressing elevated levels of p27(Kip1) protein due to stable ectopic expression displayed increased G1 arrest. Thus, green tea had significant chemopreventive effects on carcinogen-induced mammary tumorigenesis in female S-D rats. In culture, inhibition of human breast cancer cell proliferation by EGCG was mediated in part via induction of the p27(Kip1) CKI.

A comparison of three different sleep schedules for reducing daytime sleepiness in narcolepsy

STUDY OBJECTIVE

To determine if the combination of scheduled sleep periods and stimulant medications were more effective than stimulant medications alone in controlling the excessive daytime sleepiness experienced by narcoleptic patients.

DESIGN

Twenty-nine treated narcoleptic subjects were randomly assigned to one of three treatment groups: 1) two 15-minute naps per day; 2) a regular schedule for nocturnal sleep; or 3) a combination of scheduled naps and regular bedtimes. Measures of symptom severity and unscheduled daytime were obtained at baseline and at the end of the two-week treatment period, using the Narcolepsy Symptom Status Questionnaire (NSSQ) and 24-hour ambulatory polysomnographic monitoring. No alterations were made in stimulant medications during the study period.

SETTING

N/A.

PATIENTS OR PARTICIPANTS

N/A.

INTERVENTIONS

N/A.

MEASUREMENTS AND RESULTS

The addition of two-15 minute naps did not alter either symptom severity or the duration of unscheduled daytime sleep. Regular times for nocturnal sleep reduced perceived symptom severity, but did not reduce the amount of unscheduled daytime sleep. Only the combination of scheduled naps and regular nocturnal sleep times, significantly reduced both symptom severity and the amount of unscheduled daytime sleep in treated narcoleptic subjects. The type of sleep schedule prescribed, however, was less important than the severity of the patients' pre-treatment daytime sleepiness. Subjects with severe daytime sleepiness benefited from the addition of scheduled sleep periods, while those who were only moderately sleepy or able to maintain alertness did not benefit from scheduled sleep periods.

CONCLUSIONS

Scheduled sleep periods are helpful for only those patients who remain profoundly sleepy despite stimulant medications and should not be prescribed for all patients with narcolepsy.

Knowledge and communication difficulties for patients with chronic heart failure: qualitative study

OBJECTIVES

To explore patients' understanding of chronic heart failure; to investigate their need for information and issues concerning communication.

DESIGN

Qualitative analysis of in-depth interviews by a constant comparative approach.

PARTICIPANTS

27 patients identified by cardiology and care of the elderly physicians as having symptomatic heart failure (New York Heart Association functional class of II, III, or IV) and who had been admitted to hospital with heart failure in the past 20 months.

RESULTS

Participants were aged 38-94 (mean 69 years); 20 had a New York Heart Association classification of III or IV. All had at least one concurrent illness. Participants sought information from the research interviewer about their heart failure, their prognosis, and likely manner of death. They also described several factors that could inhibit successful communication with their doctors. These included difficulties in getting to hospital appointments, confusion, short term memory loss, and the belief that doctors did not want to provide patients with too much knowledge.

CONCLUSIONS

Good communication requires the ability both to listen and to impart relevant information. Effective and better ways of communicating with patients with chronic heart failure need to be tested. Disease specific barriers to effective communication, such as short term memory loss, confusion, and fatigue should be addressed. Strategies to help patients ask questions, including those related to prognosis, should be developed.

Expression of the aryl hydrocarbon receptor/transcription factor (AhR) and AhR-regulated CYP1 gene transcripts in a rat model of mammary tumorigenesis

Exposure to ubiquitous environmental chemicals, such as polycyclic aromatic hydrocarbons (PAH), may contribute to human breast cancer. In animals, PAH induce tumors in part by activating the aryl hydrocarbon receptor (AhR)/transcription factor. Historically, investigations into AhR-regulated carcinogenesis have focused on AhR-dependent transcriptional regulation of cytochrome P450 (CYP) enzymes which oxidize PAH to mutagenic intermediates. However, recent studies suggest that the AhR directly regulates cell growth. Given the postulated role of the AhR in carcinogenesis, we predicted that: (1) tissue predisposed to PAH tumorigenesis would express the AhR and (2) aberrant AhR and/or AhR-regulated gene expression would accompany malignant transformation. To test these hypotheses, AhR and CYP1 protein and/or mRNA levels were evaluated in rat mammary tumors induced with 7, 12-dimethylbenz[a]anthracene (DMBA), a prototypic PAH and AhR ligand. Results indicate modest AhR expression in normal mammary myoepithelial and ductal epithelial cells. In contrast, high AhR levels were detected in DMBA-induced tumors. Nuclear AhR localization in tumors suggested constitutive AhR activation. In situ hybridization and quantitative RT-PCR assays indicated high AhR mRNA levels in neoplastic epithelial cells. While both AhR-regulated CYP1A1 and CYP1B1 mRNAs were induced in breast tissue within 6 h of DMBA gavage, only CYP1B1 mRNA remained elevated in tumors. These results: (1) help explain targeting of breast tissue by carcinogenic PAH, (2) imply that AhR and CYP1B1 hyper-expression represent molecular biomarkers for, at least, PAH-induced mammary cell transformation, and (3) suggest mechanisms through which the AhR may contribute to carcinogenesis well after exogenous AhR ligands have been eliminated.

Activation of NF-kappaB/Rel occurs early during neoplastic transformation of mammary cells

NF-kappaB/Rel is a family of transcription factors which are expressed in all cells; however, in most non-B cells, they are sequestered in the cytoplasm in inactive complexes with specific inhibitory proteins, termed IkappaBs. We have recently shown that NF-kappaB/Rel factors are aberrantly activated in human breast cancer and rodent mammary tumors, and function to promote tumor cell survival and proliferation. Here, we have examined the time-course of induction of NF-kappaB/Rel factors upon carcinogen treatment of female Sprague-Dawley (S-D) rats in vivo and in human mammary epithelial cells (HMECs) in culture. We observed that NF-kappaB/Rel activation is an early event, occurring prior to malignant transformation. In S-D rats, increased NF-kappaB/Rel binding was detected in nuclear extracts of mammary glands from 40% of animals 3 weeks post-treatment with 15 mg/kg 7,12-dimethylbenz[a]anthracene (DMBA); this is prior to formation of tumors which normally begin to be detected after 7-9 weeks. In non-tumorigenic MCF-10F cells, in vitro malignant transformation upon treatment with either DMBA or benzo[a]pyrene (B[a]P) resulted in a 4- to 12-fold increase in activity of classical NF-kappaB (p65/p50). NF-kappaB induction was corrrelated with a decrease in the stability of the NF-kappaB-specific inhibitory protein IkappaB-alpha. Ectopic expression of the transactivating p65 subunit of NF-kappaB in MCF-10F cells induced the c-myc oncogene promoter, which is driven by two NF-kappaB elements, and endogenous c-Myc levels. Furthermore, reduction mammoplasty-derived HMECs, immortalized following B[a]P exposure, showed dysregulated induction of classical NF-kappaB prior to malignant transformation. Together these findings suggest that activation of NF-kappaB plays an early, critical role in the carcinogen-driven transformation of mammary glands.

Dietary fat, body weight, and cancer: contributions of studies in rodents to understanding these cancer risk factors in humans

Understanding diet and energy balance as risk factors for breast, colon, and other cancers requires information on the contribution of each factor and of interactions among factors to cancer risk. Rodent models for breast cancer provide extensive data on effects of dietary fat and calories, energy balance, body weight gain, and physical activity on tumor development. Analyses of the combined data from many studies have shown clearly that quality and quantity of dietary fat and energy balance contribute independently to increased mammary gland tumorigenesis. These findings were seen in female rats fed diets high in fat (35-40% of calories) compared to rats fed control diets, with approximately 10% of calories as fat (Fay and Freedman, 1997, Breast Cancer Res. Treat. 46, 215-223). The methods used permit comparison of experimental and epidemiological data, and they may be useful in extrapolating between species and developing public health recommendations. In addition to the contributions of lifetime-diet composition, intake, energy balance, and physical activity to cancer risk, there are questions about the timing and duration of alterations in these factors and about the "dose-response" characteristics of cancer risk to the factors. Endocrine mechanisms may be significant in mammary gland tumor risk, but experimental and epidemiological data indicate that cancers at other sites, such as colon and liver, also are influenced by the factors listed. Other diet and lifestyle factors that influence energy, or specifically fat, metabolism may also affect risk for cancers that are promoted by increased intake of fat and calories. Studies of separate and interactive effects of dietary fat, black tea, weight gain, and mammary gland tumorigenesis (Rogers, et al, 1998, Carcinogenesis 19, 1269-1273) have been analyzed. Using adjustment of carcinogenesis endpoints for body weight, tumor burden, and latency, they were found to be related to weight gain within treatment groups in 2 of 3 experiments.

Health-related quality of life effects of modafinil for treatment of narcolepsy

OBJECTIVE

To evaluate the burden of illness of narcolepsy and assess the health-related quality-of-life (HQL) effects of oral modafinil, a wake-promoting therapy for excessive daytime sleepiness associated with narcolepsy.

METHODS

Subjects with narcolepsy enrolled in a nine-week, placebo-controlled, double-blind study and were randomized to placebo, modafinil 200 mg, or modafinil 400 mg. After the study, consenting subjects received modafinil in a 40-week open-label extension. A self-administered HQL questionnaire consisting of the 36-Item Short Form Health Survey (SF-36) and supplemental narcolepsy-specific scales was given to subjects at baseline, study endpoint, and several open-label timepoints.

RESULTS

481 subjects completed a baseline and double-blind endpoint HQL assessment. Compared to population norms, baseline HQL scores reflected substantial burden in vitality, social functioning, and performing usual activities. At study endpoint, subjects in the 400 mg modafinil group had significantly higher scores than placebo for 10 of the 17 HQL scales. The 400 mg modafinil group had more energy, fewer difficulties performing usual activities, fewer interferences with social activities, improved psychological well-being and higher productivity, attention and self-esteem compared to placebo subjects (p<.05). The positive treatment effects were sustained over the open-label extension.

CONCLUSION

Modafinil significantly improves health-related quality of life in narcolepsy.

Black tea and mammary gland carcinogenesis by 7,12-dimethylbenz[a]anthracene in rats fed control or high fat diets

Epidemiological studies suggest that tea may reduce cancer risk, and in laboratory rodents, chemopreventive effects of tea or purified extracts of tea have been demonstrated in lung, gastrointestinal tract and skin. There is some evidence of chemoprevention by tea in the mammary gland, but the data are not conclusive. In order to evaluate more fully the possible influence of black tea on 7,12-dimethylbenz[a]anthracene (DMBA)-induced mammary gland tumors in the female S-D (Sprague-Dawley) rat, three large studies were performed: experiment 1, tumorigenesis in rats fed AIN-76A diet and given 25 mg/kg DMBA and 1.25 or 2.5% whole tea extract or water to drink; experiment 2, tumorigenesis in rats given 15 mg/kg DMBA and the same diet and fluids as in experiment 1; experiment 3, tumorigenesis in rats fed control or HF (high fat, corn oil) diet and given 15 mg/kg DMBA and 2% tea or water to drink. Tea was given throughout the experiment; DMBA was given by gastric gavage at 8 weeks of age. There was no consistent effect of tea on tumorigenesis in rats fed AIN-76A diet; there was, however, evidence in experiment 3 of a reduction of tumorigenesis by tea in rats fed the HF diet. In experiment 3, rats fed the HF diet and given water showed the expected increase in tumor burden (number and weight) compared with rats fed control diet. However, rats fed the HF diet and given 2% tea showed no increase in tumor burden; their tumor burden was significantly lower than in rats fed the HF diet and given water (P < 0.01) and was not different from rats fed control diet and given water or tea. In addition, in experiment 3, the number of malignant tumors per tumor-bearing rat was increased by the HF diet in water-drinking rats (P < 0.01) but not in tea-drinking rats. Therefore, it appears that tea partially blocked the promotion of DMBA-induced mammary tumorigenesis by the HF diet.

Aberrant nuclear factor-kappaB/Rel expression and the pathogenesis of breast cancer

Expression of nuclear factor-kappaB (NF-kappaB)/Rel transcription factors has recently been found to promote cell survival, inhibiting the induction of apoptosis. In most cells other than B lymphocytes, NF-kappaB/Rel is inactive, sequestered in the cytoplasm. For example, nuclear extracts from two human untransformed breast epithelial cell lines expressed only very low levels of NF-kappaB. Unexpectedly, nuclear extracts from two human breast tumor cell lines displayed significant levels of NF-kappaB/Rel. Direct inhibition of this NF-kappaB/ Rel activity in breast cancer cells induced apoptosis. High levels of NF-kappaB/Rel binding were also observed in carcinogen-induced primary rat mammary tumors, whereas only expectedly low levels were seen in normal rat mammary glands. Furthermore, multiple human breast cancer specimens contained significant levels of nuclear NF-kappaB/Rel subunits. Thus, aberrant nuclear expression of NF-kappaB/Rel is associated with breast cancer. Given the role of NF-kappaB/Rel factors in cell survival, this aberrant activity may play a role in tumor progression, and represents a possible therapeutic target in the treatment of these tumors.

Nursing management of sleep disorders: Part 1--Assessment

Insomnia and hypersomnia are the two most frequent sleep complaints. This article will focus on the assessment of these two symptoms. A thorough assessment, which includes a sleep history, information about the person's habits, a family history, a social history, a health history and a physical examination is necessary to determine the cause of patients' symptoms.

Nursing management of sleep disorders: Part 2--Behavioral interventions

Treatment of patients who are assessed as having insomnia may include pharmacologic, psychotherapy, and behavioral approaches. This article, Part 2 of "Nursing Management of Sleep Disorders," describes types of insomnia, outlines several behavioral therapies, and provides guidelines for usage of these therapies.

Considerations in the design of studies of dietary influences on mammary carcinogenesis in rats and mice

Design of diets for the study of dietary influences in mammary gland carcinogenesis requires attention to several questions: (1) Do the diets satisfy the nutritional needs of the animal under the conditions of the experiment, and are they palatable? (2) Does the protocol include determination of feed intake (if indicated) and of achievement of the desired level of nutrient deficiency, adequacy, or excess? (3) Are there potentially confounding nutrient interactions or nutrient effects or physiological or pathological responses that must be considered? The particular sensitivity of mammary gland tumorigenesis to intake of fat and calories and to body weight gain must be considered and controlled for in all experiments.

Predictive value of molecular dosimetry: individual versus group effects of oltipraz on aflatoxin-albumin adducts and risk of liver cancer

Studies in animals and humans have established serum aflatoxin-albumin adducts as biomarkers of exposure to aflatoxin B1 (AFB1), a food-borne hepatocarcinogen. To assess the utility of measurements of aflatoxin-albumin adducts to predict risk of hepatocellular carcinoma (HCC), 123 male F344 rats were dosed with 20 microg of AFB1 daily for 5 weeks after randomization into three groups: no intervention; delayed-transient (500 ppm of oltipraz, weeks 2 and 3 relative to AFB1); or persistent (500 ppm oltipraz, weeks -1 to 5). Serial blood samples were collected from each animal at weekly intervals throughout aflatoxin B1 exposure and assayed for levels of aflatoxin-albumin by radioimmune assay. Area under the curve (AUC) values for aflatoxin-albumin adducts decreased 20 and 39% in the delayed-transient and persistent oltipraz intervention groups, respectively, as compared to no intervention. Similarly, the total incidence of HCC dropped from 83 to 60% (P = 0.03) and 48% (P < 0.01) in these groups. Tumor multiplicity was also reduced in the two oltipraz intervention groups, whereas time to HCC was increased. Mononuclear cell leukemia, a common neoplasm in F344 rats, was seen in 39% of the control animals, whereas the two oltipraz interventions reduced incidence to 18% (P = 0.05) and 13% (P = 0.01), respectively. Overall, a significant association was seen between biomarker AUC and risk of HCC (P = 0.01). However, when the predictive value of aflatoxin-albumin adducts was assessed within treatment groups, there was no association between AUC and risk of HCC (P = 0.56). Thus, aflatoxin-albumin adducts can be useful for monitoring population-based changes induced by interventions, such as in chemoprevention trials, but have limited utility in identifying individuals destined to develop HCC. As a consequence, the use of this biomarker in quantitative risk assessment should be pursued cautiously.

HLA DR15 (DR2) and DQB1*0602 typing studies in 188 narcoleptic patients with cataplexy

Narcolepsy is considered a homogeneous clinical entity when excessive daytime sleepiness and cataplexy are present. Cataplexy is a polymorphic symptom that can be very mild and is thus subjectively defined. The Multiple Sleep Latency Test (MSLT) is widely used as a diagnostic test for narcolepsy. A short mean sleep latency and multiple sleep onset REM periods (SOREMPs) are typically observed in narcoleptic patients. The discovery of a tight association of narcolepsy with HLA class II antigens offers a unique opportunity to explore the respective value of the MSLT or of the presence of clear-cut cataplexy in defining an etiologically homogeneous group of narcoleptic patients. In this study, we carried out HLA typing for DR15(DR2) and DQB1*0602 in 188 narcoleptic patients with cataplexy in three ethnic groups (24 Asians, 61 Blacks, and 103 Caucasians). These results confirm the importance of DQB1*0602 typing rather than DR15 (DR2) typing in Black narcoleptic patients and demonstrate that the presence of clear-cut cataplexy is a better predictor for DQB1*0602 positivity than the presence of abnormal MSLT results.

Diet and breast cancer: studies in laboratory animals

Increasing dietary fat content increases mammary gland tumorigenesis in laboratory rodents. The effect can be attributed only in part to increasing energy intake, which itself increases tumorigenesis. Restriction of dietary or energy intake, sufficient to reduce body weight, reduces mammary gland tumorigenesis. Consideration of these effects has led to discussion of the possible need for changes in the feeding of laboratory rodents in carcinogenesis bioassays and other chronic studies. Studies of endocrine or other growth factors for the mammary gland have not identified specific effects of dietary fat or energy. In addition, tumorigenesis in other organs responds similarly to increased fat or decreased energy intake, indicating that the mechanisms are not, or not entirely, specific for the mammary gland. Extrapolations of results between species must always be made with caution, but the marked effects of dietary fat and energy in rodent tumorigenesis models must be considered in designing diet advice for humans.

Compliance with stimulant medications in patients with narcolepsy

The goals of this descriptive study were to determine what percentage of our treated narcoleptic subjects took their stimulant medications as prescribed and to examine the relationship between compliance and response to stimulant medications. Data obtained from a screening questionnaire, sleep diaries, and medical records showed that 22 of our 43 treated narcoleptic subjects reduced their dosage of stimulant medications or had not taken any stimulant medications during a 24-hour monitoring period during which they were expected to be on medication. Although we had expected better compliance among subjects who responded to stimulant medications (day-wake subjects), statistical testing revealed no significant differences between the two groups. Nor were there any significant differences in age, gender, or educational level when compliant and noncompliant subjects were compared. Only the type of drug prescribed (short versus long-acting stimulant) affected compliance; 39.4% of the subjects with prescriptions for dextroamphetamine or methylphenidate took the amount of medication prescribed compared to 87.5% of the subjects with prescriptions for pemoline.

Comparative analysis of the ternary complex factors Elk-1, SAP-1a and SAP-2 (ERP/NET)

A transcription factor ternary complex composed of Serum Response Factor (SRF) and Ternary Complex Factor (TCF) mediates the response of the c-fos Serum Response Element (SRE) to growth factors and mitogens. Three Ets domain proteins, Elk-1, SAP-1 and ERP/NET, have been reported to have the properties of TCF. Here we compare Elk-1 and SAP-1a with the human ERP/NET homologue SAP-2. All three TCF RNAs are ubiquitously expressed at similar relative levels. All three proteins contain conserved regions that interact with SRF and the c-fos SRE with comparable efficiency, but in vitro complex formation by SAP-2 is strongly inhibited by its C-terminal sequences. Similarly, only Elk-1 and SAP-1a efficiently bind the c-fos SRE in vivo; ternary complex formation by SAP-2 is weak and is substantially unaffected by serum stimulation or v-ras co-expression. All three TCFs contain C-terminal transcriptional activation domains that are phosphorylated following growth factor stimulation. Activation requires conserved S/T-P motifs found in all the TCF family members. Each TCF activation domain can be phosphorylated in vitro by partially purified ERK2, and ERK activation in vivo is sufficient to potentiate transcriptional activation.

Methyl donors in the diet and responses to chemical carcinogens

Dietary deficiency of labile methyl donors (choline and methionine) increases spontaneous and chemically induced hepatocarcinogenesis in rats. Chemical carcinogenesis in the colon, mammary gland, esophagus, and pancreas also may be increased. The mechanism of the dietary effect is not known but may be related to reduced methylation of DNA and RNA, hyperplasia of target cells, increased peroxidative damage, and altered carcinogen or promoter metabolism. Folate deficiency also is associated with increased carcinogenesis, an effect that may be mediated through participation in methyl metabolism; this has been less extensively studied. Deficiency of these three nutrients also may play a role in the elevated cancer risk in humans that is associated with ethanol intake.

Patterns of sleep and wakefulness in treated narcoleptic subjects

In most reported studies of treatment for narcolepsy, the efficacy of treatment has been assessed in the sleep laboratory, but not in the natural work and home settings. We therefore assessed the sleep/wake patterns of 25 subjects with narcolepsy, whose symptoms were considered under satisfactory control by the subjects and their physicians, using polygraphic recorders, and compared these with the patterns of 25 control subjects matched for age and gender. Data from one matched pair of subjects were excluded for technical reasons. There was no difference between the two groups of subjects in the total amount of sleep obtained during the 24-hour monitoring period. Narcoleptic subjects had shorter nocturnal sleep latencies and more disrupted nocturnal sleep than control subjects. Despite taking their usual medications, narcoleptic subjects averaged 44 minutes of daytime sleep compared to 4.8 minutes for controls. There was wide variation in the amount of daytime sleep among narcoleptics: 10 subjects did not sleep during the day, whereas the other 14 averaged 2.7 naps per day for an average of 76.2 minutes of daytime sleep. These findings indicate that daytime sleep episodes were common in narcoleptic patients who considered their treatment satisfactory. Wide variations in the amount of daytime sleep may reflect differences in disease severity, responsiveness to medications or willingness to tolerate daytime sleep episodes.

24-hour sleep/wake patterns in healthy elderly persons

The purpose of this study was to examine the 24-hour sleep/wake patterns of healthy elderly persons. Data was obtained from 14 elderly subjects who wore a wrist actigraph for 48 hours and completed an activity diary during the monitoring period. Although subjects spent slightly more than 7.5 hours in bed at night, they were asleep for just over 6 hours. Subjects did not have trouble falling asleep, but once asleep, had trouble remaining asleep. All subjects took one or more naps during the recording period, but daytime naps composed only a small fraction of their total sleep time. Total duration of daytime sleep averaged 59.8 minutes.

Diet and carcinogenesis

In summary there is a wealth of information on dietary and nutritional effects on carcinogenesis in laboratory rodents. Experimental studies based on epidemiological evidence, earlier experimental studies and known or predicted cellular, biochemical and molecular effects of nutrients have produced clear evidence that carcinogenesis in laboratory rodents is influenced by dietary intake of calories, fat, lipotropes (choline, methionine), vitamin A and related retinoids, Se, calcium, zinc, fiber, ethanol and a large number of non-nutrient components of foods. For these substances or groups of substances mechanistic hypotheses supported by experimental data and are leading to further research. The information provided will contribute to understanding of basic processes in carcinogenesis as well as of the specific interactions studied, and should contribute to significant advances in preventive medicine. Restriction of caloric intake of rodents by amounts > 10% over a significant portion of their lifetime reduces tumorigenesis. That level of restriction reduces the rate of growth and maturation, and most experiments in this area employ greater restrictions that virtually abolish growth from a young age. Therefore, the observations are of interest in mechanistic studies, but their applicability to preventive medicine requires better definition of the degree and duration of restriction required for a significant effect and the age at which it must be imposed. Restriction of total fat intake and modifications to increase the intake of omega-3 fats have a reasonably consistent effect on tumorigenesis in rodents but a much less consistently demonstrable effect in humans. Again, the observations in rodents are providing a major stimulus to mechanistic studies. The lipotropes are extremely valuable as tools for investigating mechanisms of carcinogenesis in rodents. Their importance in the epidemiology of human cancer has yet to be demonstrated clearly and is a subject of research at present. The naturally occurring vitamins and minerals, as well as fiber, derive their importance in this context from investigations to explain the consistent epidemiological demonstrations of reduction of tumor risk with increased consumption of fruits and vegetables. The activity of the isolated nutrients as anticarcinogens in rodents has generally not matched the activity expected from epidemiological studies. The anticarcinogenic activity of many of the non-nutrient components of fruits and vegetables is remarkable in particular models, however, as is the activity of natural and synthetic retinoids. At present the results must be interpreted to indicate an important effect of combinations of the whole foods with identification of particular nutrients or non-nutrients in specific cases.(ABSTRACT TRUNCATED AT 400 WORDS)

Reliability of sleep diaries for assessment of sleep/wake patterns

Although sleep diaries are widely used in clinical and research settings, only a few studies have compared the subjective information recorded in these diaries to objective information about sleep recorded. The goal of this study was to determine if a sleep diary could be used to obtain reliable data about home sleep/wake patterns over a 24-hour period. Fifty subjects (25 narcoleptic and 25 matched control subjects) completed a sleep diary while undergoing 24-hour ambulatory polysomnographic monitoring. The percentage agreement between the subjective data recorded in the sleep diaries and polysomnographic data was acceptable (kappa = .87). Sensitivity and specificity were also high (92.3% and 95.6%). The sleep diary is a reliable instrument for collecting data about sleep/wake patterns, but should be used with caution when collecting data from subjects who are likely to take frequent daytime naps.

The effect of regularly scheduled naps on sleep attacks and excessive daytime sleepiness associated with narcolepsy

To investigate the effectiveness of "nap therapy" for improving alertness and reducing the frequency of sleep attacks, 16 narcoleptic subjects were studied before, during, and after a 1-month program of three regularly scheduled naps. The frequency and timing of sleep attacks, naps, and nocturnal sleep periods were recorded daily in sleep logs for 5 weeks. The severity of five common symptoms of narcolepsy and daytime alertness were assessed before and after the 1-month treatment period. Medications and usual nocturnal sleep habits were not changed during the study period. Mean sleep latency was increased significantly after 1 month of nap therapy. However, there were no significant changes in the frequency of sleep attacks or in the severity of other symptoms. Those subjects who reported more severe symptoms and who had taken more naps daily before the study period received the most benefit from the treatment.

Protection against aflatoxin B1-induced hepatocarcinogenesis in F344 rats by 5-(2-pyrazinyl)-4-methyl-1,2-dithiole-3-thione (oltipraz): predictive role for short-term molecular dosimetry

Previous studies have demonstrated that dietary administration of the schistosomicidal drug 5-(2-pyrazinyl)-4-methyl-1,2-dithiole-3-thione (oltipraz) ameliorates the hepatotoxicity of aflatoxin B1 (AFB1). Notably, mortality, altered hepatic function, hepatic AFB1-DNA adduct levels, and expression of hepatic enzyme-altered foci were markedly reduced in the rat by concurrent feeding of oltipraz during exposures to AFB1. Collectively, these studies prompted us to evaluate the chemoprotective properties of oltipraz against AFB1-induced liver cancer. In addition, preliminary molecular dosimetry studies were undertaken to determine the utility of measurements of urinary aflatoxin-N7-guanine excretion as a marker of relative risk for hepatocarcinogenesis in AFB1-exposed rats. For the carcinogenesis studies, 5-wk-old male F344 rats were randomly divided into two groups. One group (55 rats) received the AIN-76A diet, and the other group (56 rats) received the AIN-76A diet supplemented with 0.075% oltipraz. The oltipraz-supplemented diet was fed for 4 wk. Beginning 1 wk after starting the experimental diets, all rats in both groups received 25 micrograms of AFB1/rat/day by gavage for 5 days per wk over the next 2 wk. One wk following cessation of dosing with AFB1, oltipraz was removed from the diet, and all rats were fed the AIN-76A diet for the remainder of the experiment. At 3 mo after dosing, livers of ten sentinel rats from each group were analyzed for the burden of gamma-glutamyltranspeptidase-positive foci. In accord with previous findings, rats fed the oltipraz-supplemented diet exhibited substantial reductions in the focal burden (97% reduction; P less than 0.05) of these AFB1-induced lesions. The remaining rats were maintained for the cancer study until they became moribund or the termination of the experiment at 23 mo. Gross liver lesions were identified at autopsy and confirmed by microscopic evaluation. An 11% incidence of hepatocellular carcinoma was observed in the AFB1-treated, control diet-fed rats. An additional 9% of this group had hepatocellular adenomas. Oltipraz afforded complete protection against both AFB1-induced hepatocellular neoplasms. Using Kaplan-Meier survival analyses, rats in the oltipraz group had a significantly (P less than 0.02) longer life span and an increased survival free of liver tumors (P less than 0.0002). Molecular dosimetry studies used rats fed either the oltipraz-supplemented or control diet for 1 wk and then challenged with a single dose of AFB1 to examine the initial rates of 8,9-dihydro-8-(N7-guanyl)-9-hydroxyaflatoxin B1 excreted in the urine.(ABSTRACT TRUNCATED AT 400 WORDS)

Procarbazine carcinogenicity in methotrexate-treated or lipotrope-deficient male rats

Procarbazine hydrochloride (PCZ), a chemotherapeutic agent used extensively to treat Hodgkins disease and other tumors, induces leukemia, lymphoma, mammary gland and other solid tumors in rodents and non-human primates and is strongly implicated as a leukemogen in humans. Lipotrope (choline and methionine) deficiency is a powerful potentiator of chemical carcinogenesis in liver and, under some conditions, in other tissues in rodents. Methotrexate (MTX), another commonly used chemotherapeutic agent, interferes with one-carbon metabolism and limits availability of lipotropes. Studies of PCZ carcinogenesis in lipotrope-deficient or MTX-treated male rats are reported, showing that both deficiency and MTX increased PCZ carcinogenicity in the mammary gland. In addition, PCZ was found to induce abnormalities of hepatic choline metabolism. Weanling male Sprague-Dawley rats were fed control (C) or lipotrope-deficient (D) diet. After 3 weeks, C and D rats were given PCZ, MTX, the two drugs together or 0.9% saline by i.p. injection. Doses were 0.2 or 0.5 mg MTX/kg or 25 mg PCZ/kg, given 2 or 3 days per week for 5 or 14 weeks. After 5 weeks of drug treatment livers were assayed for choline, phosphatidylcholine, phosphocholine (PCho), glycerophosphocholine and betaine. PCZ perturbed choline metabolism, increasing hepatic choline and PCho in deficient or MTX-treated rats and, to a smaller extent, in rats fed control diet. MTX markedly enhanced the effect of PCZ on choline metabolism. PCZ-induced mammary tumor incidence was increased 50-70% by lipotrope deficiency or by MTX. In PCZ-treated rats, cumulative probability of bearing a mammary tumor was significantly increased by lipotrope deficiency (P = 0.05), and was increased similarly but not significantly by MTX (P = 0.1). Cumulative tumor numbers per group in PCZ-treated rats were significantly greater in both deficient and MTX-treated rats compared to rats fed control diet (P less than 0.005). Incidences of leukemia, lymphoma and Zymbal's gland tumors induced by PCZ were not significantly altered by diet or MTX.

Tests of memory in narcoleptics

This study attempted to evaluate the validity of self-reports of memory deficits in narcoleptics by comparing the scores of these patients with the scores of matched control subjects on standardized tests of memory function. After completing a short interview designed to elicit qualitative information about memory difficulties, 30 narcoleptic subjects and 30 control subjects completed the Wechsler Memory Scale (WMS), Rey-Auditory Verbal Learning Test, the Rey Complex Figure Test, Strub and Black's List of Letters, and the Symbol Digits Modalities Test (SDMT). In addition, the Profile of Mood States (POMS) was used to detect variation in performance due to anxiety or fatigue. Continuous polygraphic recordings were obtained during the testing to detect any changes in alertness. Subjects with narcolepsy experienced more difficulty in maintaining attention than control subjects, as evidenced by significantly more perseveration errors (p less than or equal to 0.01) on Strub and Black's List of Letters. Despite differences in their ability to sustain attention, there were no significant differences between narcoleptic and control subjects on measures of concentration (Digit Span from the WMS, and the SDMT). Furthermore, there was no objective evidence of memory impairment when the scores of narcoleptic and control subjects were compared on standardized tests of immediate and delayed recall, as well as on tests of verbal and visual memory.

Anguidine-induced testicular injury in Lewis rats

Anguidine (diacetoxyscirpenol, DAS) and other trichothecene mycotoxins are potent inhibitors of protein synthesis and injure organs with rapidly dividing cell populations, including the testis. Testicular structure and function were studied in male Lewis rats 1, 3, 7, 30, 60, and 90 days after exposure at age 12 weeks to anguidine at 1.7 mg/kg body weight given by ip injection. The dose was equivalent to 75% of the ip LD50. Anguidine caused a gradual decline in testicular weight beginning 30 days after treatment. Sperm production was also reduced by 30 days, and the frequency of hypocellular seminiferous tubules increased by day 60. There was no evidence of recovery by 90 days. These changes are consistent with injury to proliferating cells early in the maturation sequence. Epididymal sperm reserves were reduced by 3 days after anguidine administration, prior to the reduction in sperm production, suggesting premature release of spermatozoa from the epididymis.