Cutaneous metastases as the presenting feature of lung cancer

Lung cancer is the second most common cancer diagnosed in men and women worldwide with the highest mortality. A rare site of metastases for lung cancer is the skin. Typically, the diagnosis is secure prior to developing cutaneous metastases. We present a case of a man in his mid-70s who presented to dermatology with cutaneous metastases. We outline the presentation, diagnostic workup and management of this case. We also review the literature of cutaneous metastases in lung cancer; highlighting the clinical need for a timely accurate diagnosis and the implication in terms of prognosis.

Food insecurity and its consequences in indigenous children and youth in Canada

Food insecurity (FI) is at a crisis level in some Indigenous communities and impacts many of the half million First Nations Inuit and Métis (FNIM) children across Canada, particularly in isolated northern communities. This can lead to malnutrition and can have significant impacts on the physical, intellectual, emotional and social development of a child, often with lasting effects across the life course. This is a narrative review article with extensive search of the medical literature with input from the FNIM National organizations. The primary cause of FI is an imbalance between the high price of food relative to household income, where poverty is a driving factor. The cost and lack of availability to healthy foods has resulted in a transition to unhealthy market foods. Food security programs need to be prioritized, multi-faceted and multi-tiered within a framework of food sovereignty. Translational science, research, to practice is also important. The use of successful Indigenous based models of FI, towards food sovereignty using self-determination, Indigenous Knowledge, strength-based models, and ancestral sustainability are critical. Continued community-based evaluation of FI towards sustainable healthy food programs are important for communities to initiate track, evaluate, and grow robust community-based programs to counter-balance FI. Continued scientific research in the fields of FI, food sovereignty, and their relationship to co-occurring conditions related to healthy eating and beverage consumption are vastly important to the health of Indigenous Peoples. These are all part of many Indigenous connection to the earth, through food source, the maintenance of health through ancestral ways of living, set in the premise of looking forward multiple generations towards the continued resiliency through food, diet, relationship, and sovereignty. Food Security is a human right and needs to be urgently addressed for Indigenous children in Canada.

Near-Fatal Self-Harm Among Canadian Adolescents

OBJECTIVE

To evaluate the clinical features of Canadian adolescents admitted to the intensive care unit (ICU) for medically serious self-harm.

METHODS

2700 Canadian paediatricians were surveyed monthly over two years (January 2017 to December 2018) through the Canadian Paediatric Surveillance Program to ascertain data from eligible cases.

RESULTS

Ninety-three cases (73 female; age 15.2 ± 1.5) met the case definition. Four provinces reported the majority of cases: Quebec (n = 27), Ontario (n = 26), Alberta (n = 21), and British Columbia (n = 8). There were 10 deaths, 9 by hanging. Overdose and hanging were the most frequently reported methods of self-harm (74.2% and 19.4%, respectively). Overdose was more common in females (80.8% females vs. 50% males; χ² = 7.8 (1), p = .005), whereas hanging was more common in males (35% males vs. 15.1% females, χ² = 3.9 (1), p = .04). More females than males had a past psychiatric diagnosis (79% vs. 58%; χ² = 4.1 (1), p = .06), a previous suicide attempt (55.9% vs. 29.4%, χ² = 3.8 (1), p = .05), and prior use of mental health service (69.7% vs. 27.8%, χ² = 10.4 (1), p = .001). Family conflict was the most commonly identified precipitating factor (43%) of self-harm.

CONCLUSIONS

Among Canadian adolescents admitted to the ICU with medically serious self-harm, females demonstrate a higher rate of suicide attempts and prior mental health care engagement, whereas males are more likely to die by suicide. These findings are consistent with data from other adolescent samples, as well as data from working-age and older adults. Therefore, a sex-specific approach to suicide prevention is warranted as part of a national suicide prevention strategy; family conflict may be a specific target for suicide prevention interventions among adolescents.

Preventing symptomatic vitamin D deficiency and rickets among Indigenous infants and children in Canada

Vitamin D deficiency (VitDD) rickets and other manifestations of severe VitDD, such as cardiomyopathy and hypocalcemic seizures, continue to be diagnosed in Canada. Breastfed Indigenous infants, particularly those living in northern communities, are disproportionately impacted, although formula-fed infants are not exempt in cases where the mother's vitamin D status is critically low. This statement deals with the prevention of rickets and hypocalcemia due to VitDD for Indigenous children, and revises an earlier document from the Canadian Paediatric Society. An assessment of the risk for VitDD is recommended for each maternal-infant dyad because of the link between maternal and infant VitDD. Along with supports for enhanced adherence, additional VitD supplementation is recommended for prenatal women and infants deemed at high risk and, in certain situations, intermittent higher dose supplementation may be required. Food insecurity can also contribute to rickets, so advocacy is required to prevent VitDD rickets in Indigenous children.

Retrospective application of the HEAR score on patients evacuated for chest pain: Assessing the utility of point-of-care troponin

Introduction

The HEART scoring system codifies the clinical gestalt used by physicians with 0-2 points assigned to 5 criteria (history, electrocardiography, age, risk factors and troponin). This scoring provides a prognostic tool that assists in disposition planning. The use of a truncated HEART score, minus the troponin data (HEAR score), was used for patients presenting with chest pain at one of four outpost nursing stations served by La Ronge Health Centre in northern Saskatchewan. These nursing stations have no onsite physician and no ability to obtain any troponin data. This study set out to determine if there was any utility in conducting point-of-care (PoC) troponins in these nursing outposts.

Materials and Methods

A retrospective analysis was conducted using the La Ronge regional electronic medical record by searching for all patients for whom an outpost nurse had called a physician regarding chest pain symptoms between 01 January 2011 and 31 December 2016. The HEAR and HEART score were then calculated for each individual presentation of patients with chest pain that met inclusion and exclusion criteria.

Results

By calculating both the patient's HEART score before evacuation from the outposts and after (i.e. with the troponin data), we were able to determine that, in 89.4% of cases (110/123 events), patients would require evacuation regardless of the troponin values due to a HEART score ≥4. In 10.6% (13/124 events) of cases, the patients who were evacuated had a HEART score ≤3, and in only one case did the troponin data increase this score.

Conclusions

The majority of patients would continue to be evacuated regardless of the result of their PoC troponin due to an already elevated HEAR score. PoC troponin is unlikely to reduce the rate of evacuation of patients with chest pain from the nursing stations served by the La Ronge Health Centre.

Perinatal and Early-Life Nutrition, Epigenetics, and Allergy

Epidemiological studies have shown a dramatic increase in the incidence and the prevalence of allergic diseases over the last several decades. Environmental triggers including risk factors (e.g., pollution), the loss of rural living conditions (e.g., farming conditions), and nutritional status (e.g., maternal, breastfeeding) are considered major contributors to this increase. The influences of these environmental factors are thought to be mediated by epigenetic mechanisms which are heritable, reversible, and biologically relevant biochemical modifications of the chromatin carrying the genetic information without changing the nucleotide sequence of the genome. An important feature characterizing epigenetically-mediated processes is the existence of a time frame where the induced effects are the strongest and therefore most crucial. This period between conception, pregnancy, and the first years of life (e.g., first 1000 days) is considered the optimal time for environmental factors, such as nutrition, to exert their beneficial epigenetic effects. In the current review, we discussed the impact of the exposure to bacteria, viruses, parasites, fungal components, microbiome metabolites, and specific nutritional components (e.g., polyunsaturated fatty acids (PUFA), vitamins, plant- and animal-derived microRNAs, breast milk) on the epigenetic patterns related to allergic manifestations. We gave insight into the epigenetic signature of bioactive milk components and the effects of specific nutrition on neonatal T cell development. Several lines of evidence suggest that atypical metabolic reprogramming induced by extrinsic factors such as allergens, viruses, pollutants, diet, or microbiome might drive cellular metabolic dysfunctions and defective immune responses in allergic disease. Therefore, we described the current knowledge on the relationship between immunometabolism and allergy mediated by epigenetic mechanisms. The knowledge as presented will give insight into epigenetic changes and the potential of maternal and post-natal nutrition on the development of allergic disease.

109 Near-fatal suicide attempts among Canadian Youth: A CPSP Study

Background

Suicide is the second leading cause of death among Canadian adolescents. Youth who make near fatal suicide attempts, such as those requiring intensive care unit (ICU) level care, are the closest proxy to those that die by suicide; however, there is limited data on this group.

Objectives

To evaluate the minimum incidence rate and patterns of presentation of youth (under 18 years of age) admitted to the ICU for medically serious self-inflicted injury.

Design/Methods

From January 2017 to December 2018, over 2,700 paediatricians/subspecialist members of the Canadian Paediatric Surveillance Program were electronically surveyed on a monthly basis regarding cases of medically serious self-harm. Participants completed a detailed questionnaire about the reported case and descriptive statistics were used for analyses.

Results

Ninety-four cases (71 female; mean age 15.2 years) of confirmed (n=87) and suspected/probable (n=7) medically serious self-harm were reported. The majority (87%) of cases were reported from 4 out of 13 provinces and territories in Canada (Alberta, British Columbia, Ontario, Quebec). There were 11 deaths by suicide (M>F; p<.05). Medication ingestion was the most common method of self-harm among females (76% F vs. 52% M; p=.03) compared with hanging among males (14% F vs. 39% M; p=.009). More females than males had a prior suicide attempt (62% F vs. 32% M; p=.07) and a history of non-suicidal self-injury (NSSI) (65% F vs. 14% M; p<.05), although only history of NSSI reached significance. More females than males had a past psychiatric diagnosis (77% F vs. 55% M; p=.05), and past use of mental health services (69% F vs. 30% M; p<.001), although only service use reached significance. Half of the youth left evidence of intent (54%) and 33% of parents of included youth were aware that their child was considering suicide. Family conflict was the most common precipitating factor for suicide attempt in both females and males (46%).

Conclusion

These Canadian findings are consistent with international epidemiologic data that observe a gender paradox of higher rates of suicide attempts in females and greater mental health care engagement but increased suicide mortality in males with decreased involvement with mental health care. This study suggests that family conflict is a potential target for suicide prevention interventions among youth. Future research focusing on gender-specificity in risk factor identification and effectiveness of primary prevention interventions among youth is warranted.

Explaining the variability in cardiovascular risk factors among First Nations communities in Canada: a population-based study

BACKGROUND

Historical, colonial, and racist policies continue to influence the health of Indigenous people, and they continue to have higher rates of chronic diseases and reduced life expectancy compared with non-Indigenous people. We determined factors accounting for variations in cardiovascular risk factors among First Nations communities in Canada.

METHODS

Men and women (n=1302) aged 18 years or older from eight First Nations communities participated in a population-based study. Questionnaires, physical measures, blood samples, MRI of preclinical vascular disease, and community audits were collected. In this cross-sectional analysis, the main outcome was the INTERHEART risk score, a measure of cardiovascular risk factor burden. A multivariable model was developed to explain the variations in INTERHEART risk score among communities. The secondary outcome was MRI-detected carotid wall volume, a measure of subclinical atherosclerosis.

FINDINGS

The mean INTERHEART risk score of all communities was 17·2 (SE 0·2), and more than 85% of individuals had a risk score in the moderate to high risk range. Subclinical atherosclerosis increased significantly across risk score categories (p<0·0001). Socioeconomic advantage (-1·4 score, 95% CI -2·5 to -0·3; p=0·01), trust between neighbours (-0·7, -1·2 to -0·3; p=0·003), higher education level (-1·9, -2·9 to -0·8, p<0·001), and higher social support (-1·1, -2·0 to -0·2; p=0·02) were independently associated with a lower INTERHEART risk score; difficulty accessing routine health care (2·2, 0·3 to 4·1, p=0·02), taking prescription medication (3·5, 2·8 to 4·3; p<0·001), and inability to afford prescription medications (1·5, 0·5 to 2·6; p=0·003) were associated with a higher INTERHEART risk score. Collectively, these factors explained 28% variation in the cardiac risk score among communities. Communities with higher socioeconomic advantage and greater trust, and individuals with higher education and social support, had a lower INTERHEART risk score. Communities with difficulty accessing health care, and individuals taking or unable to afford prescription medications, had a higher INTERHEART risk score.

INTERPRETATION

Cardiac risk factors are lower in communities with high socioeconomic advantage, greater trust, social support and educational opportunities, and higher where it is difficult to access health care or afford prescription medications. Strategies to optimise the protective factors and reduce barriers to health care in First Nations communities might contribute to improved health and wellbeing.

FUNDING

Heart and Stroke Foundation of Canada, Canadian Partnership Against Cancer, Canadian Institutes for Health Research.

PTSD in women is associated with a block in conversion of progesterone to the GABAergic neurosteroids allopregnanolone and pregnanolone measured in plasma

There is a need to identify new and more effective treatments for posttraumatic stress disorder (PTSD). Allopregnanolone and its stereoisomer pregnanolone (together termed ALLO) are metabolites of progesterone that positively and allosterically modulate GABA effects at GABA_A receptors, thereby reducing anxiety and depression. Previous research revealed that women with PTSD had low cerebrospinal fluid (CSF) ALLO levels and a low ratio of ALLO to the allopregnanolone precursor 5α-DHP, consistent with deficient activity of the ALLO synthetic enzyme 3α-hydroxysteroid dehydrogenase (3α-HSD). The current study examined ALLO and the ratio of ALLO to 5α-DHP in plasma at rest and in response to psychophysiological stressors in trauma-exposed, medication-free women with and without PTSD. Participants were examined twice in random order during the early follicular phase (eFP) and mid-luteal phase (mLP) of the menstrual cycle. Plasma neurosteroids were measured using gas chromatography-mass spectrometry. Results indicate that the ALLO to 5α-DHP ratio in plasma increases between the eFP and mLP. In addition, women with PTSD have a lower ratio of ALLO to 5α-DHP than trauma-exposed healthy women, as well as blunted increases in this ratio in response to a moderately stressful laboratory procedure, i.e., differential fear conditioning, across the menstrual cycle. Clinically feasible testing for 3α-HSD dysfunction is critical to translating this line of research into clinical care. Measurement of this ratio in plasma could facilitate patient stratification in clinical treatment trials, as well as precision medicine targeting of treatments that address ALLO synthesis deficits in women with PTSD.

Integrated genome and transcriptome sequencing identifies a noncoding mutation in the genome replication factor DONSON as the cause of microcephaly-micromelia syndrome

While next-generation sequencing has accelerated the discovery of human disease genes, progress has been largely limited to the “low hanging fruit” of mutations with obvious exonic coding or canonical splice site impact. In contrast, the lack of high-throughput, unbiased approaches for functional assessment of most noncoding variants has bottlenecked gene discovery. We report the integration of transcriptome sequencing (RNA-seq), which surveys all mRNAs to reveal functional impacts of variants at the transcription level, into the gene discovery framework for a unique human disease, microcephaly-micromelia syndrome (MMS). MMS is an autosomal recessive condition described thus far in only a single First Nations population and causes intrauterine growth restriction, severe microcephaly, craniofacial anomalies, skeletal dysplasia, and neonatal lethality. Linkage analysis of affected families, including a very large pedigree, identified a single locus on Chromosome 21 linked to the disease (LOD > 9). Comprehensive genome sequencing did not reveal any pathogenic coding or canonical splicing mutations within the linkage region but identified several nonconserved noncoding variants. RNA-seq analysis detected aberrant splicing in DONSON due to one of these noncoding variants, showing a causative role for DONSON disruption in MMS. We show that DONSON is expressed in progenitor cells of embryonic human brain and other proliferating tissues, is co-expressed with components of the DNA replication machinery, and that Donson is essential for early embryonic development in mice as well, suggesting an essential conserved role for DONSON in the cell cycle. Our results demonstrate the utility of integrating transcriptomics into the study of human genetic disease when DNA sequencing alone is not sufficient to reveal the underlying pathogenic mutation.

Parasitic zoonoses: one health surveillance in northern Saskatchewan

We report the results of a joint human-animal health investigation in a Dene community in northern Saskatchewan, where residents harvest wildlife (including moose, bear, elk, and fish), live in close contact with free roaming dogs, and lack access to permanent veterinary services. Fecal analysis of owned and free-roaming dogs over two consecutive years (N = 92, 103) identified several parasites of public health concern, including Toxocara canis, Diphyllobothrium spp., Echinococcus/Taenia, Cryptosporidium spp. and Giardia spp. Administration of pyrantel pamoate to a subset of dogs (N = 122) in the community in the first year was followed by reduced shedding of T. canis and other roundworms in the second year, demonstrating the potential utility of canine de-worming as a public health intervention. Using direct agglutination tests with confirmatory indirect fluorescent antibody test, 21% of 47 dogs were sero-positive for exposure to Toxoplasma gondii. Using enzyme-linked immunosorbent assay (ELISA) sero-prevalence rates in 201 human volunteers were as follows: Toxoplasma gondii (14%), Echinococcus granulosus (48%), Toxocara canis (13%) and Trichinella spp. (16%). Overall 65% of participants were sero-positive for at least one parasite. A survey administered to volunteers indicated few associations between widely accepted risk factors for parasite exposure and serological status, emphasizing the importance of environmental transmission of these parasites through soil, food, and waterborne routes.

Parasites are ubiquitous, and while some parasitize only one host, others are capable of crossing species barriers. Zoonotic parasites move between animals and people, and in some cases cause significant veterinary, medical and/or public health problems. Such parasites may be more prevalent in areas where veterinary and medical services are scarce, and especially if sanitation infrastructure is suboptimal. Additional risk factors include reliance on country foods, proximity to pets that come in contact with wildlife, and eating undercooked or raw fish and game. We visited one northern Indigenous community over two consecutive years to determine the prevalence of internal parasites in dogs, as well as to demonstrate the effect of selective deworming on reducing environmental contamination by zoonotic parasites. In addition, we collected blood samples and administered surveys to human volunteers in order to explore the relationship between exposure to four zoonotic parasites and several widely accepted risk factors for exposure (e.g. pet ownership). Our findings indicate that levels of parasite exposure in this community were higher than similar studies conducted in other Canadian Indigenous communities. Public health interventions that utilize a one health strategy by integrating medical, veterinary and environmental expertise may be the most effective approach in reducing human and animal exposure to parasites in this community.

Characterization of Escherichia coli urinary tract infection isolates in remote northern Saskatchewan communities: the Northern Antibiotic Resistance Partnership

Antimicrobial resistance is a growing concern especially in many remote northern communities of Canada where antimicrobials are liberally used. In this study, 1418 Escherichia coli urinary tract infection (UTI) isolates, obtained over a 2.5-year period (October 2005-March 2008), from 3 remote northern sites in Saskatchewan, Canada, were identified. Antimicrobial susceptibility testing of the first 544 clinically significant isolates revealed high prevalence of resistance to trimethoprim-sulfamethoxazole (TMP-SXT) (30.7%). Pulsed-field gel electrophoresis (PFGE) of 165 TMP-SXT-resistant isolates revealed a heterogeneous population. Multilocus sequence typing identified 7 STs from 9 identified PFGE clusters, which included separate PFGE clusters of fluoroquinolone-resistant and -susceptible ST131 isolates. The majority of TMP-SXT-resistant isolates (85.5%) were found to carry class 1 integrons, and plasmids from 62 (81%) of 77 representative isolates were successfully transformed into E. coli DH10B. Overall, ampicillin was the most common plasmid-encoded resistance phenotype transferred with TMP-SXT at 60% (37/62). Further characterization of 52 plasmids by restriction fragment length polymorphism and replicon typing revealed the presence of many plasmid lineages, suggesting that the elevated rates of TMP-SXT resistance in these communities are most likely attributed to the horizontal transfer of class 1 integrons. Results from this study emphasize the importance of continued surveillance of remote northern communities in order to optimize the efficacy of empiric UTI treatment.

Community-associated methicillin-resistant Staphylococcus aureus in Indigenous communities in Canada

Community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) infections have emerged as a significant issue in some Indigenous communities (including First Nations, Inuit and Métis) in Canada. Primarily associated with skin and soft-tissue infections, this organism can also result in significant morbidity and mortality. Canadian and American guidelines for managing CA-MRSA infections have been published. The specific epidemiology, microbiology and susceptibility patterns, and the social/environmental circumstances of CA-MRSA infections in Indigenous communities need to be considered for strategies to reduce transmission. While reducing household crowding and improving in-home potable water supply are optimal strategies to reduce the impact of this illness, implementing Canadian guidelines along with increased prevention strategies are recommended as interim measures.

Community-based educational intervention to limit the dissemination of community-associated methicillin-resistant Staphylococcus aureus in Northern Saskatchewan, Canada

BACKGROUND

Surveillance examining the incidence of community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) was conducted over 8 years beginning in 2001 in three health regions covering the northern half of Saskatchewan. The annual rate of individuals reported with CA-MRSA infection in these regions dramatically increased from 8.2 per 10,000 population in 2001 (range to 4.4-10.1 per 10,000) to 168.1 per 10,000 in 2006 (range 43.4-230.9 per 10,000). To address this issue, a team of community members, healthcare professionals, educators and research scientists formed a team called "the Northern Antibiotic Resistance Partnership" (NARP) to develop physician, patient, community, and school based educational materials in an attempt to limit the spread of CA-MRSA.

METHODS

Posters, radio broadcasts, community slide presentations, physician treatment algorithms, patient pamphlets, and school educational programs Do Bugs Need Drugs http://www.dobugsneeddrugs.org and Germs Away http://www.germsaway.ca were provided to targeted northern communities experiencing high rates of infections.

RESULTS

Following implementation of this program, the rates of MRSA infections in the targeted communities have decreased nearly two-fold (242.8 to 129.3 infections/10,000 population) from 2006 to 2008. Through pre-and post-educational intervention surveys, this decrease in MRSA infections coincided with an increase in knowledge related to appropriate antimicrobial usage and hand washing in these communities.

CONCLUSION

These educational materials are all freely available http://www.narp.ca and will hopefully aid in increasing awareness of the importance of proper antimicrobial usage and hygiene in diminishing the spread of S. aureus and other infectious diseases in other communities.

High-frequency analysis of the complex linkage between soil CO(2) fluxes, photosynthesis and environmental variables

High-frequency soil CO(2) flux data are valuable for providing new insights into the processes of soil CO(2) production. A record of hourly soil CO(2) fluxes from a semi-arid ponderosa pine stand was spatially and temporally deconstructed in attempts to determine if variation could be explained by logical drivers using (i) CO(2) production depths, (ii) relationships and lags between fluxes and soil temperatures, or (iii) the role of canopy assimilation in soil CO(2) flux variation. Relationships between temperature and soil fluxes were difficult to establish at the hourly scale because diel cycles of soil fluxes varied seasonally, with the peak of flux rates occurring later in the day as soil water content decreased. Using a simple heat transport/gas diffusion model to estimate the time and depth of CO(2) flux production, we determined that the variation in diel soil CO(2) flux patterns could not be explained by changes in diffusion rates or production from deeper soil profiles. We tested for the effect of gross ecosystem productivity (GEP) by minimizing soil flux covariance with temperature and moisture using only data from discrete bins of environmental conditions (±1 °C soil temperature at multiple depths, precipitation-free periods and stable soil moisture). Gross ecosystem productivity was identified as a possible driver of variability at the hourly scale during the growing season, with multiple lags between ~5, 15 and 23 days. Additionally, the chamber-specific lags between GEP and soil CO(2) fluxes appeared to relate to combined path length for carbon flow (top of tree to chamber center). In this sparse and heterogeneous forested system, the potential link between CO(2) assimilation and soil CO(2) flux may be quite variable both temporally and spatially. For model applications, it is important to note that soil CO(2) fluxes are influenced by many biophysical factors, which may confound or obscure relationships with logical environmental drivers and act at multiple temporal and spatial scales; therefore, caution is needed when attributing soil CO(2) fluxes to covariates like temperature, moisture and GEP.

High rates of Staphylococcus aureus USA400 infection, Northern Canada

Surveillance of Staphylococcus aureus infections in 3 northern remote communities of Saskatchewan was undertaken. Rates of methicillin-resistant infections were extremely high (146–482/10,000 population), and most (98.2%) were caused by USA400 strains. Although USA400 prevalence has diminished in the United States, this strain is continuing to predominate throughout many northern communities in Canada.

Diagnosis and high incidence of hyperornithinemia-hyperammonemia-homocitrullinemia (HHH) syndrome in northern Saskatchewan

Mutations in the SLC25A15 gene, encoding the human inner mitochondrial membrane ornithine transporter, are thought to be responsible for hyperornithinemia-hyperammonemia-homocitrullinemia (HHH) syndrome, a rare autosomal recessive condition. HHH syndrome has been detected in several small, isolated communities in northern Saskatchewan (SK). To determine the incidence of HHH syndrome in these communities, a PCR method was set up to detect F188Δ, the common French-Canadian mutation. Neonatal blood spots collected from all newborns from the high risk area were genotyped for the F188Δ mutation for seven consecutive years. Using DNA analysis, we estimated that the heterozygote frequency for the mutant allele for HHH syndrome to be about 1 in 19 individuals, predicting one affected child with HHH syndrome for approximately every 1,500 individuals (1 in 1,550 live births; 1 child every 12 years) in this isolated population. The frequency for the mutant allele for HHH syndrome in this isolated community is probably the highest in the world for this rare disorder. We determined that ornithine levels, by tandem mass spectrometry, were not abnormal in newborns with F188Δ mutation, carriers and normals. Ornithine rises to abnormally high levels at some time after birth well past the time that the newborn screening blood spot is collected. The timing or the reasons for the delayed rise of ornithine in affected children with HHH syndrome have not been determined. Newborn screening for HHH Syndrome in this high risk population is only possible by detection of the mutant allele using DNA analysis.

Evaluating capture stress and its effects on reproductive success in Svalbard reindeer

Although many ecological studies of wild animal populations rely on capturing individuals at least once, few have investigated either the immediate stress responses of capture, restraint, and handling, or the longer term consequences on reproductive success. In this paper, we assume that the degree of stress increase with the time taken to capture and process an animal prior to release. The influence of time since onset of capture on body temperature and blood chemistry indicators of stress was investigated in 137 adult female Svalbard reindeer ( Rangifer tarandus platyrhynchus Vrolik, 1829) and 63 calves of both sexes captured by net in late-winter 2004 and 2005. In addition, we looked for evidence of negative effects of capture stress on reproductive success in marked animals over the period from 1995 to 2006. Body temperature increased with both chase time and the time the animals were restrained. In the latter case, body temperature increased twice as fast in nonpregnant animals (0.13 °C/min) compared with pregnant animals. Cortisol, glutamate dehydrogenase, and γ-glutamyltransferase all increased with time from onset of capture. However, the relationship for glucose with time since onset of capture increased initially before declining again. We found no evidence of a lower calving success in animals captured the previous winter when compared with animals that had not been captured the previous winter. Likewise, there was no relationship between the strength of the acute stress response (measured as cortisol concentrations) and the probability of pregnant females having a calf at foot the subsequent summer.

Protein kinase Cζ: A novel protective neonatal T-cell marker that can be upregulated by allergy prevention strategies

BACKGROUND

Variations in neonatal T-cell function have been associated with allergic disease.

OBJECTIVES

To examine the relationship between neonatal T-cell protein kinase (PKC) expression and subsequent allergic disease.

METHODS

T cells were purified from cord blood samples (n = 74) obtained from a cohort of mothers who received either 4 g/d fish oil or a placebo from 20 weeks of gestation. PKC expression was examined in relationship to supplementation, fatty acid levels, cytokine production, and allergic outcomes at 1 year and 2.5 years of age.

RESULTS

Neonatal T-cell PKCzeta expression was lower in children who had evidence of allergic disease at 1 year (P = .001) and 2.5 years (P = .052) of age. It was also lower in children with sensitization (positive skin prick test) at each age (P = .02 and P = .072, respectively). PKCzeta expression was inversely correlated to PKCalpha (r = -0.28; P = .025), which was strongly related to IL-5 responses to allergens (ovalbumin, r = 0.59; P = .003; dust mite, r = 0.52; P = .011) at 1 year of age. Fish oil supplementation was associated with significantly higher PKCzeta expression (P = .014), whereas most other isozymes were reduced by fish oil supplementation.

CONCLUSION

This is the first study to show that allergic disease is associated with altered expression of T-cell PKC isozymes in the neonatal period. It has also demonstrated that fish oil can modulate expression of PKC isozymes in a potentially favorable direction.

CLINICAL IMPLICATIONS

Protein kinase Czeta should be explored further as an early marker and potential target for disease prevention.

Plasticity in hydraulic architecture of Scots pine across Eurasia

Widespread tree species must show physiological and structural plasticity to deal with contrasting water balance conditions. To investigate these plasticity mechanisms, a meta-analysis of Pinus sylvestris L. sap flow and its response to environmental variables was conducted using datasets from across its whole geographical range. For each site, a Jarvis-type, multiplicative model was used to fit the relationship between sap flow and photosynthetically active radiation, vapour pressure deficit (D) and soil moisture deficit (SMD); and a logarithmic function was used to characterize the response of stomatal conductance (G(s)) to D. The fitted parameters of those models were regressed against climatic variables to study the acclimation of Scots pine to dry/warm conditions. The absolute value of sap flow and its sensitivity to D and SMD increased with the average summer evaporative demand. However, relative sensitivity of G(s) to D (m/G (s,ref), where m is the slope and G(s,ref) is reference G(s) at D = 1 kPa) did not increase with evaporative demand across populations, and transpiration per unit leaf area at a given D increased accordingly in drier/warmer climates. This physiological plasticity was linked to the previously reported climate- and size-related structural acclimation of leaf to sapwood area ratios. G (s,ref), and its absolute sensitivity to D(m), tended to decrease with age/height of the trees as previously reported for other pine species. It is unclear why Scots pines have higher transpiration rates at drier/warmer sites, at the expense of lower water-use efficiency. In any case, our results suggest that these structural adjustments may not be enough to prevent lower xylem tensions at the driest sites.

Novel action of n-3 polyunsaturated fatty acids: inhibition of arachidonic acid-induced increase in tumor necrosis factor receptor expression on neutrophils and a role for proteases

OBJECTIVE

Neutrophils and tumor necrosis factor (TNF) play important roles in the pathogenesis of rheumatoid arthritis (RA). Modulation of TNF receptors (TNFRs) may contribute to the regulation of tissue damage, and n-6 polyunsaturated fatty acids (PUFAs) such as arachidonic acid (AA) can increase the expression of TNFRI and TNFRII on neutrophils. Because the n-3 PUFAs are antiinflammatory in RA, we examined whether, as a novel mechanism of action, n-3 PUFAs can antagonize the AA-induced increase in TNFR expression.

METHODS

Human neutrophils were treated with PUFAs and examined for changes in surface expression of TNFRs by flow cytometry. Translocation of protein kinase C (PKC) and activation of ERK-1/2 MAPK were determined by Western blotting. Intracellular calcium mobilization was measured in Fura 2-loaded cells by luminescence spectrometry.

RESULTS

Pretreatment of neutrophils with nanomolar levels of n-3 PUFAs, eicosapentaenoic acid, or docosahexaenoic acid led to a marked inhibition of the AA-induced up-regulation of TNFRs I and II. Such pretreatment, however, did not prevent AA from stimulating the activities of PKC and ERK-1/2, which is required for the actions of AA or its ability to mobilize Ca(2+). Nevertheless, treatment with n-3 PUFAs caused the stimulation of serine proteases that could cleave the TNFRs.

CONCLUSION

These findings suggest a mechanism by which the n-3 PUFAs inhibit the inflammatory response in RA, by regulating the ability of AA to increase TNFR expression. These results help fill the gaps in our knowledge regarding the mechanisms of action of n-3 PUFAs, thus allowing us to make specific recommendations for the use of n-3 PUFAs in the regulation of inflammatory diseases.

Radionuclides and trace metals in Canadian moose near uranium mines: comparison of radiation doses and food chain transfer with cattle and caribou

Tissues from 45 moose and 4 cattle were collected to assess the health of country foods near uranium mines in northern Saskatchewan. Bone, liver, kidney, muscle and rumen contents were analyzed for uranium, radium-226 (226Ra), lead-210 (210Pb), and polonium-210 (210Po). Cesium-137 (137Cs), potassium-40 (40K), and 27 trace metals were also measured in some tissues. Within the most active mining area, Po in liver and muscle declined significantly with distance from tailings, possibly influenced by nearby natural uranium outcrops. Moose from this area had significantly higher 226Ra, 210Pb, 210Po, and 137Cs in some edible soft tissues vs. one control area. However, soil type and diet may influence concentrations as much as uranium mining activities, given that a) liver levels of uranium, 226Ra, and 210Po were similar to a second positive control area with mineral-rich shale hills and b) 210Po was higher in cattle kidneys than in all moose. Enhanced food chain transfer from rumen contents to liver was found for selenium in the main mining area and for copper, molybdenum and cadmium in moose vs. cattle. Although radiological doses to moose in the main mining area were 2.6 times higher than doses to control moose or cattle, low moose intakes yielded low human doses (0.0068 mSv y(-1)), a mere 0.3% of the dose from intake of caribou (2.4 mSv y(-1)), the dietary staple in the area.

Age-related changes in ecosystem structure and function and effects on water and carbon exchange in ponderosa pine

As forests age, their structure and productivity change, yet in some cases, annual rates of water loss remain unchanged. To identify mechanisms that might explain such observations, and to determine if widely different age classes of forests differ functionally, we examined young (Y, approximately 25 years), mature (M, approximately 90 years) and old (O, approximately 250 years) ponderosa pine (Pinus ponderosa Dougl. ex P. Laws.) stands growing in a drought-prone region of central Oregon. Although the stands differed in tree leaf area index (LAIT) (Y = 0.9, M = 2.8, O = 2.1), cumulative tree transpiration measured by sap flow did not differ substantially during the growing season (100-112 mm). Yet when water was readily available, transpiration per unit leaf area of the youngest trees was about three times that of M trees and five times that of O trees. These patterns resulted from a nearly sixfold difference in leaf specific conductance (KL) between the youngest and oldest trees. At the time of maximum transpiration in the Y stand in May-June, gross carbon uptake (gross ecosystem production, GEP) was similar for Y and O stands despite an almost twofold difference in stand leaf area index (LAIS). However, the higher rate of water use by Y trees was not sustainable in the drought-prone environment, and between spring and late summer, KL of Y trees declined fivefold compared with a nearly twofold decline for M trees and a < 30% reduction in O trees. Because the Y stand contained a significant shrub understory and more exposed soil, there was no appreciable difference in mean daily latent energy fluxes between the Y stand and the older stands as measured by the eddy-covariance technique. These patterns resulted in 60 to 85% higher seasonal GEP and 55 to 65% higher water-use efficiency at the M and O stands compared with the Y stand.

An EST survey of the sugarcane transcriptome

Its large genome and high polyploidy makes sugarcane (Saccharum spp.) a singularly challenging crop to study and improve using genetic approaches. To provide large numbers of functionally characterized candidate genes that might be tested for direct association (rather than distant linkage) with economically important traits, we sequenced the 5' ends of 9,216 clones from three cDNA libraries (apex, leaf and mature internode), representing 3,401 non-redundant sequences. About 57% of these sequences could be assigned a tentative function based on statistically significant similarity to previously characterized proteins or DNA sequences. Another 28% corresponded to previously identified, but uncharacterized, sequences. Some of the remaining unidentified sequences were predicted to be genes which could potentially be new to plants or unique to sugarcane. Comparisons of the sugarcane ESTs to a large sorghum EST database revealed similar compositions of expressed genes between some different tissues. Comparison to a detailed Arabidopsis protein database showed some highly conserved sequences, which might be useful DNA markers for pan-angiosperm comparative mapping. These EST sequences provide a foundation for many new studies to accelerate isolation of agronomically important genes from the cumbersome sugarcane genome.

Relaxation to bradykinin in bovine pulmonary supernumerary arteries can be mediated by both a nitric oxide-dependent and -independent mechanism

1. The aim of the present study was to determine the relative contribution of prostanoids, nitric oxide and K(+) channels in the bradykinin-induced relaxation of bovine pulmonary supernumerary arteries. 2. In endothelium-intact, but not denuded rings, bradykinin produced a concentration-dependent relaxation (pEC(50), 9.6+/-0.1), which was unaffected by the cyclo-oxygenase inhibitor indomethacin. The nitric oxide scavenger hydroxocobalamin (200 micro M, pEC(50), 8.5+/-0.2) and the nitric oxide synthase inhibitor L-NAME (100 micro M, pEC(50), 8.9+/-0.1) and the combination of L-NAME and hydroxocobalamin (pEC(50), 8.1+/-0.2) produced rightward shifts in the bradykinin concentration response curve. 3. The guanylyl cyclase inhibitor ODQ (10 micro M, pEC(50), 9.6+/-0.4) did not affect the response to bradykinin. 4. Elevating the extracellular [K(+)] to 30 mM did not affect the response to bradykinin but abolished the response when ODQ or L-NAME was present. 5. The K(+) channel blocker apamin (100 nM), combined with charybdotoxin (100 nM), produced a small reduction in the maximum response to bradykinin but they abolished the response to bradykinin when ODQ, L-NAME or hydroxocobalamin were present. Apamin (100 nM) combined with iberiotoxin (100 nM) also reduced the response to bradykinin in the presence of hydroxocobalamin or L-NAME. 6. The concentration response curve for sodium nitroprusside-induced relaxation was abolished by ODQ (10 micro M) and shifted to the right by apamin and charybdotoxin. 7. These studies suggest that in bovine pulmonary supernumerary arteries bradykinin can stimulate the formation of nitric oxide and activate an EDHF-like mechanism and that either of these pathways alone can mediate the bradykinin-induced relaxation. In addition nitric oxide, acting through guanylyl cyclase, can activate an apamin/charbydotoxin-sensitive K(+) channel in this tissue.

Canopy stomatal conductance and xylem sap abscisic acid (ABA) in mature Scots pine during a gradually imposed drought

We investigated the effect of drought on canopy stomatal conductance (g(c)), and examined the hypothesis that g(c) is controlled by the chemical messenger abscisic acid (ABA) produced in roots. Beginning in November 1994, we subjected a mature stand of Scots pine (Pinus sylvestris L.) to an imposed 11-month drought. Control plots were maintained at average-season soil water content. Xylem sap was extracted from shoots at regular intervals from April to November 1995. Soil water, sap flow and leaf water potentials (predawn to dusk) were recorded at the same time. Canopy stomatal conductance was calculated from sap flow data and xylem sap ABA concentrations ([ABA(xyl)]) were measured by radioimmunoassay. Mean [ABA(xyl)] in control trees was 250 micromol m(-3). No diurnal variation in [ABA(xyl)] was detected. With soil drying, [ABA(xyl)] increased to a maximum in summer (600 micromol m(-3)), but decreased again toward autumn; however, no significant increase in ABA flux to the leaves occurred. A decline in g(c) was detected when volumetric soil water content declined below 0.12. The decline in g(c) could not have been mediated by increasing [ABA(xyl)] because stomatal closure appeared to precede any increase in [ABA(xyl)]. Peak sap flow velocity data were used to estimate delivery times for root-to-shoot signals in 15-m tall trees. Under normal field conditions, a signal would take 12 days to travel from the site of production (roots) to the presumed site of action (shoots). However, under drought conditions it may take a chemical signal in excess of 6 weeks. We conclude that a feedforward model of short-term stomatal response to soil drying, based solely on the action of a chemical messenger from the roots, is not applicable in mature conifer trees because signal transmission is too slow.

Water limitations to carbon exchange in old-growth and young ponderosa pine stands

We investigated the impact of seasonal soil water deficit on the processes driving net ecosystem exchange of carbon (NEE) in old-growth and recently regenerating ponderosa pine (Pinus ponderosa Doug. ex Laws.) stands in Oregon. We measured seasonal patterns of transpiration, canopy conductance and NEE, as well as soil water, soil temperature and soil respiration. The old-growth stand (O) included two primary age classes (50 and 250 years), had a leaf area index (LAI) of 2.1 and had never been logged. The recently regenerating stand (Y) consisted predominantly of 14-year-old ponderosa pine with an LAI of 1.0. Both stands experienced similar meteorological conditions with moderately cold wet winters and hot dry summers. By August, soil volumetric water content within the upper 30 cm had declined to a seasonal minimum of 0.07 at both sites. Between April and June, both stands showed similar rates of transpiration peaking at 0.96 mm day(-1); thereafter, trees at the Y site showed increasing drought stress with canopy stomatal resistance increasing 6-fold by mid-August relative to values for trees at the O site. Over the same period, predawn water potential (psi(pd)) of trees at the Y site declined from -0.54 to -1.24 MPa, whereas psi(pd) of trees at the O site remained greater than -0.8 MPa throughout the season. Soil respiration at the O site showed a strong seasonal correlation with soil temperature with no discernible constraints imposed by declining soil water. In contrast, soil respiration at the Y site peaked before seasonal maximal soil temperatures and declined thereafter with declining soil water. No pronounced seasonal pattern in daytime NEE was observed at either site between April and September. At the Y site this behavior was driven by concurrent soil water limitations on soil respiration and assimilation, whereas there was no evidence of seasonal soil water limitations on either process at the O site.

Psychological adjustment to familial-genetic risk assessment for ovarian cancer: predictors of nonadherence to surveillance recommendations

OBJECTIVE

To evaluate whether self-report measures of psychological distress and perceived risk were associated with nonadherence to recommended ovarian cancer surveillance.

METHODS

Eighty-three patients attending the Familial Ovarian Cancer Clinic (FOCC) at Princess Margaret Hospital were assessed psychosocially prior to and during initial familial-genetic assessment and then monitored for adherence with recommended follow-up surveillance over a period of 12-18 months. The assessment protocol included an investigator-designed clinic questionnaire, the State-Trait Anxiety Inventory (STAI), Center for Epidemiologic Studies Depression Scale (CESD), Life Orientation Test (LOT), Medical Outcomes Study Social Support Survey (MOSSS), Texas Inventory of Grief, and the COPE. Nonadherence was measured in terms of unexplained absences at one or two recommended and scheduled surveillance appointments following the familial-genetic assessment.

RESULTS

Univariate tests revealed a significant association between higher perception of ovarian cancer risk, as assessed immediately after the familial-genetic risk assessment in the clinic and nonadherence to physician-recommended surveillance (chi2 (2, N = 83) = 9.75, P < 0.008). Empirically based estimates of risk, conveyed by the clinic team to subjects, were not significantly associated with nonadherence (chi2 (2, N = 83) = 0.19, P = 0.91). Logistic regression analysis revealed that subjects who perceived themselves to be at high ovarian cancer risk were five times more likely to be nonadherent than participants who perceived themselves to be at low or medium ovarian cancer risk.

CONCLUSIONS

These results suggest that higher self-perceived risk may predict adherence difficulties to recommended surveillance in women attending a familial-genetic risk clinic.

The disconnect: infertility patients' information and the role they wish to play in decision making

OBJECTIVE

To determine the preferred role in medical decision making of women undergoing fertility treatments and to establish whether their knowledge of treatments is adequate to inform their choices.

METHODS

Self-report survey of 404 women undergoing fertility treatments in 2 university hospitals and a private fertility clinic in Canada.

RESULTS

The women had been in fertility treatment for 2.3 +/- 2.6 years; 67.8% reported taking fertility drugs. Most (61.7%) women wanted to share knowledge equally with their doctors about possible fertility treatments. However, about half wanted to decide alone or mostly by themselves about the acceptability of treatment risks and benefits (56%), what treatments should be selected (49.8%), and when to conclude treatments (54.3%). In addition, 55.1% of the women did not know their personal eventual chances of pregnancy with fertility treatment or thought it was 50% or greater. Over half of the women (57.2%) who had taken fertility drugs were unaware of a possible link between fertility drugs and increased ovarian cancer risk. The majority of women (61.8%) who knew of this possible association reported that they learned about it from the print media. Women who knew of the association had a poor understanding of the strength of the evidence or the ability to detect or treat ovarian cancer successfully, and 88.3% thought they could reduce cancer risk by following their doctors' advice.

CONCLUSIONS

Despite these women's wishes to actively participate in fertility treatment decisions, they lacked the necessary information to do so meaningfully. Public health policymakers, professional and advocacy organizations, physicians, other healthcare providers, and women themselves must find ways to improve the general public's and patients' understanding about fertility treatment outcomes and risks.

Psychological factors and depressive symptoms in ischemic heart disease

The aim of this study was to determine whether learned helplessness, cognitive distortions, self-efficacy, and dispositional optimism assessed at Time 1 (T1; questionnaires mailed at 1 month postdischarge) would predict depressive symptoms at Time 2 (T2; questionnaires mailed at 1-year follow-up) in a sample of 86 patients hospitalized with ischemic heart disease. Multiple regression results indicated that optimism and cognitive distortions at T1 were significantly associated with T1 depressive symptoms after controlling for confounding variables. When the T1 psychological factors were analyzed with T2 depressive symptoms, only optimism continued to predict depressive symptoms after controlling for confounds and T1 depressive symptoms. The global expectancies that optimism assessed appeared to be more stable over time than the statelike beliefs of cognitive distortions and may have accounted for why optimism predicted T2 depressive symptoms.

The 2000 Canadian recommendations for the management of hypertension: Part one--therapy

OBJECTIVE

To provide updated, evidence-based recommendations for the therapy of hypertension in adults.

OPTIONS

For patients with hypertension, there are a number of lifestyle manoeuvres and antihypertensive agents that may control blood pressure. Randomized trials evaluating first- line therapy with thiazides, beta-adrenergic antagonists, angiotensin-converting enzyme inhibitors, calcium channel blockers, alpha-blockers, centrally acting agents or angiotensin II receptor antagonists were reviewed.

OUTCOMES

The health outcomes considered were changes in blood pressure, cardiovascular morbidity, and cardiovascular and/or all-cause mortality rates. Economic outcomes were not considered due to insufficient evidence.

EVIDENCE

Medline searches were conducted from the period of the last revision of the Canadian Recommendations for the Management of Hypertension (May 1998 to October 2000). Reference lists were scanned, experts were polled, and the personal files of the subgroup members and authors were used to identify other studies. All relevant articles were reviewed and appraised, using prespecified levels of evidence, by content experts and methodological experts.

VALUES

A high value was placed on the avoidance of cardiovascular morbidity and mortality.

BENEFITS, HARMS, AND COSTS

Various lifestyle manoeuvres and antihypertensive agents reduce the blood pressure of patients with sustained hypertension. In certain settings, and for specific classes of drugs, blood pressure lowering has been associated with reduced cardiovascular morbidity and/or mortality.

RECOMMENDATIONS

The present document contains detailed recommendations pertaining to all aspects of the therapy of patients with hypertension, including lifestyle modifications proven to lower blood pressure, treatment thresholds, target blood pressures, choice of agents in various settings and strategies to enhance adherence. Lower thresholds for blood pressure treatment are advocated for people with other cardiovascular risk factors or established hypertensive target organ damage. Implicit in the recommendations for therapy is the principle that treatment should be individualized for each patient and the choice of agent should be dictated by coexistent conditions. For the treatment of uncomplicated essential hypertension, thiazides, beta-adrenergic antagonists, angiotensin-converting enzyme inhibitors or calcium channel blockers may be appropriate, depending on individual circumstances.

VALIDATION

All recommendations were graded according to strength of the evidence and voted on by the Canadian Hypertension Recommendations Working Group. Only those recommendations achieving high levels of consensus are reported here. These guidelines will be updated annually.

Psychological factors and depressive symptoms in ischemic heart disease

The aim of this study was to determine whether learned helplessness, cognitive distortions, self-efficacy, and dispositional optimism assessed at Time 1 (T1; questionnaires mailed at 1 month postdischarge) would predict depressive symptoms at Time 2 (T2; questionnaires mailed at 1-year follow-up) in a sample of 86 patients hospitalized with ischemic heart disease. Multiple regression results indicated that optimism and cognitive distortions at T1 were significantly associated with T1 depressive symptoms after controlling for confounding variables. When the T1 psychological factors were analyzed with T2 depressive symptoms, only optimism continued to predict depressive symptoms after controlling for confounds and T1 depressive symptoms. The global expectancies that optimism assessed appeared to be more stable over time than the statelike beliefs of cognitive distortions and may have accounted for why optimism predicted T2 depressive symptoms.