Laurie Hoffman-Goetz

Exercise and the immune system: a model of the stress response?

Exercise influences natural immunity, T- and B-cell functions, and cytokine responses, through circulatory (hemodynamic) changes and by endocrine hormones secreted in response to physical stress. The magnitude of the effects on the immune system reflects the intensity, duration and chronicity of the exercise. In this review, Laurie Hoffman-Goetz and Bente Klarlund Pedersen suggest that exercise-immune interactions can be viewed as a subset of stress immunology.

Defining and measuring acculturation: a systematic review of public health studies with Hispanic populations in the United States.

In this systematic review we sought to identify how the public health literature focusing on Hispanic populations in the United States defined and measured the concept of acculturation. A review of 134 studies found considerable variation in the definition and measurement of this construct. The ten acculturation scales used provided little theoretical orientation. It was unclear the extent to which acculturative changes in attitudes, beliefs and behaviors were captured by current measurement tools, as these primarily measure linguistic elements. We suggest future research should refine existing tools, determine their validity and usefulness across ethnic and subethnic groups, and identify which aspects of acculturation these scales and indices reliably measure. Recommendations for use of acculturation instruments in public health practice with Hispanic populations are included.

Possible mechanisms mediating an association between physical activity and breast cancer

The epidemiologic, methodologic, and biologic evidence that physical activity may be related inversely to breast cancer risk was the focus of a recent workshop. This article presents the workshop summary on biologic mechanisms that may mediate this association between physical activity and breast cancer. There is some evidence that physical activity may reduce breast cancer risk, although the exact biologic pathways have not been determined. Among the potential mechanisms discussed at the workshop were reductions in endogenous steroid exposure, alterations in menstrual cycle patterns, delay of age at menarche, increased energy expenditure and reduction in body weight, changes in insulin‐like and other growth factors, and enhancement of natural immune mechanisms. Although physical activity may prove to be a modifiable risk factor for breast cancer, further mechanistically oriented research is necessary to both verify whether this is the case and to clarify the details of this association so that public health recommendations can be developed. Cancer 1998;83:621‐628.

Health literacy and the World Wide Web: Comparing the readability of leading incident cancers on the Internet

Primary objective: to assess the readability level of Web-based information on leading incident cancers. Research design: websites on breast, prostate, and colorectal cancers were selected for analysis by comparing the first 100 hits across 10 popular search engines. A total of 100 websites on breast (n = 33), prostate (n = 34), and colorectal (n = 33) cancers were included in the final analysis. Methods: readability was assessed using SMOG, Flesch-Kincaid (F – K), and Flesch Reading Ease (FRE) measures. SMOG was hand-calculated on 10 – 30 lines of continuous text. Identical text was entered into Microsoft® Word 2002 where F – K and FRE scores were determined automatically by the word processor. Results: the mean readability score of the cancer websites was Grade 12.9 using SMOG and Grade 10.7 according to F – K. The mean FRE score was 45.3, a score considered ‘difficult’. Colorectal cancer websites were most difficult to read compared to breast and prostate cancer websites. All measures indicated that prostate cancer websites were written at the lowest readability. Significantly higher reading levels were required for concluding paragraphs of Web articles compared to introduction paragraphs. Conclusions: findings suggest the need for readable cancer information on the Web. Health promoters, health informaticians, medical journalists, and web page editors must collaborate to ensure the use of plain language to match the literacy skills of consumers.

Risk Messages About HPV, Cervical Cancer, and the HPV Vaccine Gardasil: A Content Analysis of Canadian and U.S. National Newspaper Articles

The human papillomavirus vaccine (Gardasil) is a significant advancement in womens health. We compared the reporting of fear-inducing messages about human papillomavirus, cervical cancer, and the human papillomavirus vaccine in Canadian and U.S. national newspapers between January 2006 and December 2007. Significant differences between countries were found in the number of articles containing fear messages about human papillomavirus, cervical cancer, and the human papillomavirus vaccine. Educational level of readability was higher than recommended for the public, and the emotional tone of the articles became progressively negative over time. Our findings suggest that public discussion of some elements of the human papillomavirus vaccine message that could cause alarm or worry for women may need to be addressed within political and cultural contexts.

Effect of exercise on natural cytotoxicity and pulmonary tumor metastases in mice.

Exercise has been demonstrated to reduce experimental tumor formation in rodents when the exercise is present during the tumor initiation or promotion phases. This study evaluated whether exercise influenced the process of tumor metastasis and subsequent growth in a secondary implant site. Male C3H mice remained sedentary, were given free access to running wheels, ran on a treadmill (15 m.min-1, 30 min.d-1), or walked on a treadmill (5 m.min-1, 5 min.d-1)(N = 20/group). Following 9 wk of this protocol, exercise was discontinued. At this time all animals received a tumor cell dose (CIRAS 1, 3 x 10(5)) i.v., and remained sedentary until sacrificed 3 wk later. Splenic natural killer (NK) cell activity was elevated in the wheel running mice compared with sedentary controls 3 wk after cessation of exercise (F(3,74) = 6.266, P < 0.002). Exercised mice displayed lower tumor cell retention in the lungs relative to nonexercised mice (F(1,37) = 6.593, P < 0.02). Tumor incidence was not different across activity groups whereas tumor multiplicity was higher in mice that had been previously exposed to exercise. (However, it should be noted that the significant exercise-tumor effect was due to a small number of exercised mice with extreme multiplicity, > 200 foci/lung.) More extensive tumor colony formation was present in wheel-trained mice that displayed the greatest volumes of daily running. The results from this study suggest that exercise was able to augment natural immune cytotoxic function for up to 3 wk after cessation of activity. However, this augmentation of natural immune function was not associated with reduced tumor incidence in the exercised animals.

Assessment of Cultural Sensitivity of Cancer Information in Ethnic Print Media

Ethnic minority populations prefer cancer information that is respectful of their customs and beliefs about health and illness. Community newspapers are an important source of cancer information for ethnic groups. Our purpose is to evaluate the cultural sensitivity of cancer information in mass print media targeting ethnic minority readership. We assessed for cultural sensitivity 27 cancer articles published in English-language ethnic newspapers (Jewish, First Nations, Black/Caribbean, East Indian) in 2000 using the Cultural Sensitivity Assessment Tool (CSAT). We found that the overall average CSAT score of 27 cancer articles was 2.71. (Scores < 2.50 were classified as culturally insensitive.) Articles in First Nations newspapers were more culturally sensitive according to the CSAT , followed by articles in Black/Caribbean and Jewish papers. Cancer articles from East Indian newspapers had a mean CSAT score of 2.30 and were classified as culturally insensitive. Four articles were considered culturally sensitive but did not mention ethnic populations as intended readers or as high-risk groups for cancer. We found that, using the CSAT measure, overall, cancer articles in ethnic newspapers included in this study were culturally sensitive. Given limitations of this instrument, we recommend an additional checklist for evaluating the cultural sensitivity of printed cancer information.

Understanding the Barriers to Physical Activity for Cancer Patients: Review and Recommendations

Abstract For individuals who experience cancer, regular adherence to physical activity has been shown to provide benefits ranging from alleviation of symptoms to improvements in physical function and quality of life. However, research about barriers to participation that compromise adherence and subsequent benefits has been identified as needed. The purposes of this article were to (1) systematically review the barriers to research and make recommendations, (2) consider unique symptoms of disease and treatment regarding their barrier-related impact on exercise therapy, and (3) present an organizational framework that will aid the investigation and understanding of barriers as they affect adherence to prescribed exercise therapy for cancer treatment and recovery.

Chronic Disease Coverage in Canadian Aboriginal Newspapers

Purpose: To determine the volume and focus of articles on four chronic diseases in newspapers targeting First Nations, Me´tis, and Inuit in Canada. Methods: From a sampling frame of 31 Aboriginal newspapers published in English from 1996-2000, 14 newspapers were randomly selected allowing for national and regional representation. Newspaper archives were searched at the National Library of Canada and articles selected if the disease terms cancer, cardiovascular disease, diabetes, or HIV/AIDS appeared in the headline, or in the first or last paragraph of the article. Articles were coded for inclusion of mobilizing information (local, distant, unrestricted, not specified, none) and content focus (scientific, human interest, commercial, other). Cancer articles were categorized by tumor site specificity. Data were analyzed by frequency, cross tabulations, and chi-square analysis. Results: Of 400 chronic disease articles, there were significantly more articles on HIV/AIDS (167 or 41.8%) and diabetes (135 or 33.8%) and few articles on cancer (56 or 14%) and cardiovascular disease (30 articles or 7.5%) (p<0.001). Slightly more than one third (36.5%) of the articles contained mobilizing information to enable readers to take further health action. Mobilizing information was virtually absent from cardiovascular (7/30 or 23%) and diabetes (29/135 or 21.5%) articles. Site specific cancer coverage differed significantly from chance (p<0.001) with 41% of the articles on breast cancer and no articles on lung or colorectal cancers. Interpretation: Given the burden of tobacco-related cardiovascular disease and cancer in Canadian Aboriginal people, the lack of coverage and limited mobilizing information in ethnic newspapers are a missed opportunity for health promotion.

Effect of environmental enrichment and housing density on immune system reactivity to acute exercise stress

Positive stress has been described in the literature but not well characterized experimentally. This experiment was designed to test the hypothesis that environmental enrichment and housing density in C57BL/6 female mice modulate immune responses to acute exercise stress. A 2 x 2 x 2 factorial design was used where enrichment (enrich), nonenriched (nonenrich), group housed (group), individually housed (ind), and stress (stress) or no stress (nonstress) acted as the independent variables. Enrichment involved a 7-week exposure to in-cage running wheels and a variety of cage objects. Ninety minutes after treadmill exercise stress at 25 m/min, 4 degrees slope, for 30 min (or no exercise stress) mice were sacrificed, and splenocyte blastogenesis to the T-cell mitogen concanavalin A (Con A), splenic T-cell subset enumeration, and percent live/dead splenic cells by flow cytometry were evaluated. Results showed significant interaction effects for mitogen responses, percent Ly2+ subset, and percent live/dead splenocyte responses. Proliferation to Con A was higher in nonenrich group-housed animals than other groups. Percent live/dead cell analysis revealed a significant housing x stress interaction with fewer percent live and higher percent metabolically stressed splenocytes obtained from ind-stressed mice than other groups. These data suggest that enrichment and housing density are important factors influencing immune responses in the basal state, and in response to exercise stress.