Comprehensive characterization of commercially available canine training aids.

Effective and reliable training aids for victim recovery canine teams is essential for law enforcement and investigative purposes. Without adequate training aids, the rate of recovery for sub surface or surface human remains deposition using canine teams may be adversely affected and result in confusing information. The composition of three commercially available canine training aids that purportedly generate volatile components responsible for the odor of human decomposition is relatively simple and not closely related to those compounds experimentally determined to be present at the site of surface or sub-surface human remains. In this study, these different commercial formulations were chemically characterized using six different sampling approaches, including two applications of direct liquid injection, solid-phase microextraction (SPME), purge and trap, ambient preconcentration/thermal desorption, and cryogenic preconcentration/thermal desorption. Direct liquid injections resulted in the fewest number of detected compounds, while a cryogen based thermal desorption method detected the greatest number of compounds in each formulation. Based solely upon the direct liquid injection analysis, Pseudo™ Scent I was composed of approximately 29±4% and 71±5% of 2-pyrrolidinone and 4-aminobutanoic acid, respectively. This same analysis showed that Pseudo™ Scent II was composed of approximately 11±1, 11±1, 24±5, and 54±7% of putrescine, cadaverine, 2-pyrrolidinone, and 4-aminobutanoic acid, respectively. Headspace analysis was conducted to more closely simulate the process whereby a canine's nose would capture a volatiles profile. More compounds were detected using the headspace sampling method; however, the vast majority was not consistent with current data on human decomposition. Additionally, the three formulations were tested in outdoor and indoor scenarios by a double-blinded canine team, using a certified and specifically trained victim recovery canine with multiple confirmed recoveries, to determine if the formulations would be recognized by that canine as being related to human decomposition. The canine used in this study did not provide a positive response to any of the formulations tested in either test scenario. The implications for locating residual human decomposition odor in the absence of recoverable material are discussed in light of these data.

Trichloroethylene induces methylation of the Serca2 promoter in H9c2 cells and embryonic heart.

Trichloroethylene (TCE) is a halogenated hydrocarbon used as a solvent in industrial settings and in house-cleaning products. Exposure to TCE has been linked to increased risk for congenital heart malformations in both human and animal models. Previous studies showed TCE exposure reduced the expression and function of the ATP-dependent calcium pump, Serca2a, which is important for regulating calcium flux in myocytes and maintaining physiological cardiac function. In this study, we investigated whether TCE reduced Serca2a expression by altering the methylation status of its proximal promoter region. Low doses of TCE exposure (10 ppb) induced DNA hyper methylation in the Serca2 promoter region in cardiac myoblast cells and rat embryonic cardiac tissue. TCE exposure induced DNA methylation in a region of the Serca2 promoter which is the target for SP1 binding site essential for regulation of Serca2a transcriptional activity. Chromatin immunoprecipitation data confirmed that TCE exposure reduced the binding of SP1 to the Serca2 promoter region adjacent to the methylated CpG dimer. Finally, low-dose TCE exposure reduced the concentration of S-adenosyl-methionine in exposed cells and embryos. These cumulative data indicate that epigenetic mechanisms, including DNA methylation, may be important in mediating the teratogenic effects of TCE in embryonic heart.

Gene expression profiling in the fetal cardiac tissue after folate and low-dose trichloroethylene exposure.

BACKGROUND: Previous studies show gene expression alterations in rat embryo hearts and cell lines that correspond to the cardio-teratogenic effects of trichloroethylene (TCE) in animal models. One potential mechanism of TCE teratogenicity may be through altered regulation of calcium homeostatic genes with a corresponding inhibition of cardiac function. It has been suggested that TCE may interfere with the folic acid/methylation pathway in liver and kidney and alter gene regulation by epigenetic mechanisms. According to this hypothesis, folate supplementation in the maternal diet should counteract TCE effects on gene expression in the embryonic heart. APPROACH: To identify transcriptional targets altered in the embryonic heart after exposure to TCE, and possible protective effects of folate, we used DNA microarray technology to profile gene expression in embryonic mouse hearts with maternal TCE exposure and dietary changes in maternal folate. RESULTS: Exposure to low doses of TCE (10 ppb) caused extensive alterations in transcripts encoding proteins involved in transport, ion channel, transcription, differentiation, cytoskeleton, cell cycle, and apoptosis. Exogenous folate did not offset the effects of TCE exposure on normal gene expression, and both high and low levels of folate produced additional significant changes in gene expression. CONCLUSIONS: A mechanism by which TCE induces a folate deficiency does not explain altered gene expression patterns in the embryonic mouse heart. The data further suggest that use of folate supplementation, in the presence of this toxin, may be detrimental and not protective of the developing embryo.

The influence of a "culture of referral" on access to care in rural settings after myocardial infarction.

Access to care is an issue for rural people who require tertiary care following a myocardial infarction (MI). Access to specialized cardiac health services is contingent upon referral to tertiary care in urban centers. Using a critical ethnographic approach, rural women, their nurses and physicians were interviewed to explore how rurality affected women's referral and access to care following a MI. Findings reflect that a previously undocumented culture of referral that was shaped by human factors influenced access to care. The culture of referral reflected an urban-centric approach to the provision of cardiovascular services and a medical hierarchy within the referral system. The findings extend conceptual understandings of access to health care in relation to rural populations.

Trichloroethylene disrupts cardiac gene expression and calcium homeostasis in rat myocytes.

We have been investigating the molecular mechanisms by which trichloroethylene (TCE) might induce cardiac malformations in the embryonic heart. Previous results indicated that TCE disrupted expression of genes encoding proteins involved in regulation of intracellular Ca2+, [Ca2+](i), in cardiac cells, including ryanodine receptor isoform 2 (Ryr2), and sarcoendoplasmatic reticulum Ca2+ ATPase, Serca2a. These observations are important in light of the notion that altered cardiac contractility can produce morphological defects. The hypothesis tested in this study is that the TCE-induced changes in gene expression of Ca2+-associated proteins resulted in altered Ca2+ flux regulation. We used real-time PCR and digital imaging microscopy to characterize effects of various doses of TCE on gene expression and Ca2+ response to vasopressin (VP) in rat cardiac H9c2 myocytes. We observed a reduction in Serca2a and Ryr2 expression at 12 and 48 h after exposure to TCE. In addition, we found significant differences in Ca2+ response to VP in cells treated with TCE doses as low as 10 parts per billion. Taken all together, our data strongly indicate that exposure to TCE disrupts the ability of myocytes to regulate cellular Ca2+ fluxes. Perturbation of calcium signaling alters cardiac cell physiology and signal transduction and may hint to morphogenetic consequences in the context of heart development. These results point to a novel area of TCE biology and, if confirmed in vivo, may help to explain the apparent cardio-specific toxicity of TCE exposure in the rodent embryo.

Trichloroethylene and trichloroacetic acid regulate calcium signaling pathways in murine embryonal carcinoma cells p19.

Trichloroethylene (TCE) and its metabolite trichloroacetic acid (TCA) are ubiquitous environmental contaminants which have been regarded as risk factors for congenital heart malformations. An increasing body of evidence from in vivo and in vitro studies supports the notion that exposure to TCE and TCA may interfere with normal embryonic heart development. The expression of several genes coding for factors implicated in the regulation of cardiac development has been shown to be modified by TCE or TCA, but the molecular mechanisms that mediate these effects are still obscure. In this study, we investigated the global changes in gene expression caused by exposure of P19 embryonal carcinoma cells to TCE and TCA, and whether or not TCE and/or TCA influence the expression levels of genes encoding for proteins that regulate calcium fluxes in cardiac cells. We report that TCE and TCA disrupt the expression of genes involved in processes important during embryonic development suggesting that exposure to environmentally significant concentrations of TCE may have deleterious effects on specific stages of cardiac differentiation.

Exploring adolescent complementary/alternative medicine (CAM) use in Canada.

A qualitative study using a grounded theory approach investigated adolescents' perceptions about complementary/alternative medicine (CAM) use. Adolescents, attending a clinic at the Canadian College of Naturopathic Medicine, were interviewed after receiving ethics approval. Data were collected using semi-structured interviews. The decision of adolescents to use CAM was based within the context of their world and how it shaped influencing factors. Factors that influenced adolescents' decision to use CAM were identified as certain personality traits, culture, media, social contacts and the ability of CAM providers to develop therapeutic relationships. The barriers and benefits of CAM use influenced evaluation of choices. The importance of barriers in limiting freedom of choice in health care decisions should be investigated by practitioners as they provide care to adolescents. Health care planning for integrative models of care requires determining the "right" blend of expertise by knowing interprofessional boundaries, determining mixed skill sets to provide the essential services and ensuring appropriate regulation that allows practitioners to use their full scope of practice.

Preferences of patients with heart failure for prognosis communication.

BACKGROUND: Communication about prognosis is fundamental to discussions and planning for end-of-life (EOL) care for patients with advanced heart failure (HF). Little is known about the preferences of patients that could guide communication about prognosis. OBJECTIVES: To identify the preferences of patients with advanced HF regarding communication about their prognosis and its implications. METHODS: A qualitative study using a grounded theory methodology, based on one-to-one interviews with 20 patients recruited from Heart Function Clinic at the McMaster University Medical Centre in Hamilton, Ontario. RESULTS: The following four main themes about patient preferences were identified: level of wellness--patients wanted to learn about their prognosis and its implications at a time of optimal cognitive function, and not when their capacity for EOL decision making was diminished; opportunity to be informed--patients preferred physicians to initiate discussions about prognosis at the time of diagnosis; tell the truth--there was a strong preference for physicians to disclose prognostic possibilities, treatments and outcomes associated with HF, including the possibilities of deterioration and death; and maintain hope--there was a need for truth to be balanced with hope. Hope for quality of life, symptom control and control over EOL decisions were important to participants. CONCLUSIONS: The findings suggested that communication about prognosis between patients and physicians may be difficult and deferred. Preferences identified by patients offer guidance to physicians in planning and initiating dialogue about prognosis.

Fears and beliefs of patients regarding cardiac catheterization.

The fears and beliefs patients hold about invasive medical interventions may affect their perceptions about risk and subsequent decisions to undergo those procedures. Little is known about fears and beliefs in patients undergoing invasive cardiac procedures and their relationship to perceptions of risks. Using a grounded theory approach, 10 men and 10 women referred for their first cardiac catheterization (CATH) from referral centers in Ontario, Canada were interviewed to identify fears and beliefs related to the procedure. Overall, women expressed more fears than men. Fears for both groups arose from: (1) lack of control about (i) physical aspects and (ii) psychosocial aspects of the CATH; (2) an unknown future; and (3) possible medical complications. Beliefs related to health personnel involved in the CATH, the technology used during the CATH and personal coping mechanisms. Men were more inclined to believe in technology, which overrode concerns about the procedure. Participants viewed CATH as a routine and necessary step in determining their future. Patients imputed previously held fears and beliefs and formulated new ones regarding the CATH during the process of anticipating the procedure. They viewed themselves as passive participants and not as actively consenting to the CATH. This paper offers previously undocumented insights from patients regarding CATH and provides the basis for developing future investigations.

Lives of rural women after myocardial infarction.

This study examines the influences of rurality on the lives of women post-myocardial infarction (MI). Using a critical ethnographic approach, the researchers analyze in-depth interviews with 12 women from southwestern Ontario, Canada, for the ways in which their experiences were related to social, political, and cultural forces associated with rurality. Data analysis revealed 4 themes: reticence, characterized by a tendency to minimize worry and accept one's life post-MI; referral games, or the challenges associated with accessing tertiary care; resourcefulness in managing one's recovery; and relationships, with rural health professionals and institutions being highly valued. The findings have relevance for nurses in both rural and urban settings who care for women post-MI and form a basis for supporting and building culturally specific post-MI care.

Thermosensory intensity and affect throughout the perceptible range.

The thermosensory system was evaluated psychophysically in 12 healthy volunteers, spanning the full range of tolerable temperatures. Subjects provided ratings of (1) perceived thermal intensity, (2) perceived pleasantness or unpleasantness, and (3) perceived pain intensity after placing either one hand or foot in a temperature controlled water bath. Of particular interest were the interrelationships among the three perceptual measures, and differences between heat and cold. The relationship between perceived intensity and (un)pleasantness was different for hot vs cold stimuli. Specifically, for a given perceived thermal intensity, cold stimuli were rated as less pleasant or more unpleasant than hot stimuli. Similarly, for a given pain intensity, cold stimuli were rated as more unpleasant than hot stimuli. As warm temperatures increased and as cold temperatures decreased, stimuli were perceived as being unpleasant before they were perceived as being painful. The difference in transition temperatures for unpleasantness vs pain for heat averaged 1.4 degrees C, while the same difference for cold averaged 5.6 degrees C. Thus, there was a fourfold difference in the range of unpleasant but non-painful cold vs hot temperatures. Pain intensity and unpleasantness ratings were significantly higher for heat stimuli applied to the foot vs hand. In contrast, there was no significant body site difference for pain intensity or unpleasantness ratings of cold stimuli. All of these results reveal important differences in the processing of cold vs hot stimuli. These differences could be exploited to differentiate processing relevant to discriminative vs affective components of somesthetic perception, in both the innocuous and noxious ranges.