Industrialization and food safety for the Tsleil-Waututh Nation: An analysis of chemical levels in shellfish in Burrard Inlet.

While Indigenous food systems remain critical for community well-being, traditionally harvested foods are a potential source of toxic exposures. The Tsleil-Waututh Nation (TWN) is seeking to restore shellfish harvesting in Burrard Inlet (British Columbia [BC], Canada), where the cumulative effects of industrial activity have nearly eliminated safe harvesting. The Trans Mountain Expansion project would triple the capacity to transport oil through the inlet, threatening TWN's progress to restore shellfish harvesting. To inform ongoing efforts we assessed contamination by heavy metals (arsenic, cadmium, lead, and mercury) and 48 polycyclic aromatic hydrocarbons (PAHs) congeners in different shellfish species (Softshell clams, Varnish clams, and Dungeness crab) in three areas. We compared our results against local screening values (SVs) established by the TWN and BC Ministry of Environment and Climate Change Strategy, as well as provincial and national benchmarks. In total, we analyzed 18 composite samples of Softshell clams and Varnish clams (5 individuals per sample), as well as 17 individual crabs. We found chemical contamination in all species at all sites. PAHs were most frequently detected in Softshell clams, highest in the site closest to the pipeline terminus. Clams presented higher levels of contamination than crabs for PAHs, but not for heavy metals. For Softshell and Varnish clams, all heavy metals across study sites exceeded at least one of the population-specific SVs. Of the 14 PAHs detected, benzo(a)pyrene presented a median concentration in Softshell clams of 3.25 µ/kg, exceeding local SV for subsistence fisher. Our results call for further assessment of human health impacts related to food harvesting within Burrard Inlet and establishing a long-term coordinated program co-led by the TWN to monitor contamination and inform future harvesting programs. The study draws attention to the need to consider locally-relevant toxicity benchmarks, and include potential health impacts of food contamination in appraising development project proposals.

A simple method to evaluate groundwater vulnerability in urbanizing agricultural regions.

A methodology to evaluate groundwater vulnerability was developed and tested in a case study in the Central Valleys of the state of Oaxaca, Mexico, a region known for intensive agricultural activities and poor water management policies. An analysis was conducted to create and evaluate scenarios reflecting anthropogenic and natural stressors on groundwater using an analytical hierarchy process (AHP) and geographic information systems. Uncertainty in the vulnerability model was assessed using a Monte Carlo analysis. Five indices (abstraction (Abs), pollution (Po), runoff (Ru), groundwater recharge (Re), and marginalization (Ma)) were selected after an evaluation of the effects of population growth, climatology, hydrogeological features, and social marginalization on access to groundwater. Abstraction, pollution, and recharge rates are the main drivers of groundwater vulnerability, accounting for 87% of the vulnerability. The analysis revealed that the proposed model generates consistent results and contains low uncertainty. It also showed that more than 50% of the region's groundwater is moderately, and the vulnerability has become increasingly with abstraction, reduced recharge, and pollution (the most sensitive indices), indicating that groundwater in the Central Valleys is under great stress. Pollution and abstraction of groundwater resources are expected to rise in the more vulnerable areas, which will increase water crises and reduce access to water in rural communities. The approach and the indicators establish a baseline for the management and protection of water resources in developing countries where high-resolution data are lacking.

The Canadian healthy infant longitudinal development birth cohort study: biological samples and biobanking.

BACKGROUND: It is hypothesised that complex interactions between genetic and environmental factors give rise to allergy and asthma in childhood. The Canadian Healthy Infant Longitudinal Development (CHILD) study was designed to explore these factors. METHODS: CHILD is a longitudinal, general population birth cohort study following infants from mid-pregnancy to age 5 years. Over this time period, biological samples, questionnaires, clinical measures and environmental data are collected. RESULTS: A total of 3624 families have been recruited, and many thousands of samples and questionnaires have been collected, annotated, and archived. This report outlines the rationale and methodology for collecting and storing diverse biological samples from parents and children in this study, and the mechanisms for their release for analyses. CONCLUSIONS: The CHILD sample and data repository is a tremendous current and future resource and will provide a wealth of information not only informing studies of asthma and allergy, but also potentially in many other aspects of health relevant for Canadian infants and children.

The association between campylobacteriosis, agriculture and drinking water: a case-case study in a region of British Columbia, Canada, 2005-2009.

We studied the association between drinking water, agriculture and sporadic human campylobacteriosis in one region of British Columbia (BC), Canada. We compared 2992 cases of campylobacteriosis to 4816 cases of other reportable enteric diseases in 2005-2009 using multivariate regression. Cases were geocoded and assigned drinking water source, rural/urban environment and socioeconomic status (SES) according to the location of their residence using geographical information systems analysis methods. The odds of campylobacteriosis compared to enteric disease controls were higher for individuals serviced by private wells than municipal surface water systems (odds ratio 1·4, 95% confidence interval 1·1-1·8). In rural settings, the odds of campylobacteriosis were higher in November (P = 0·014). The odds of campylobacteriosis were higher in individuals aged ⩾15 years, especially in those with higher SES. In this region of BC, campylobacteriosis risk, compared to other enteric diseases, seems to be mediated by vulnerable drinking water sources and rural factors. Consideration should be given to further support well-water users and to further study the microbiological impact of agriculture on water.

Associations between bacterial communities of house dust and infant gut.

The human gut is host to a diverse and abundant community of bacteria that influence health and disease susceptibility. This community develops in infancy, and its composition is strongly influenced by environmental factors, notably perinatal anthropogenic exposures such as delivery mode (Cesarean vs. vaginal) and feeding method (breast vs. formula); however, the built environment as a possible source of exposure has not been considered. Here we report on a preliminary investigation of the associations between bacteria in house dust and the nascent fecal microbiota from 20 subjects from the Canadian Healthy Infant Longitudinal Development (CHILD) Study using high-throughput sequence analysis of portions of the 16S rRNA gene. Despite significant differences between the dust and fecal microbiota revealed by Nonmetric Multidimensional Scaling (NMDS) analysis, permutation analysis confirmed that 14 bacterial OTUs representing the classes Actinobacteria (3), Bacilli (3), Clostridia (6) and Gammaproteobacteria (2) co-occurred at a significantly higher frequency in matched dust-stool pairs than in randomly permuted pairs, indicating an association between these dust and stool communities. These associations could indicate a role for the indoor environment in shaping the nascent gut microbiota, but future studies will be needed to confirm that our findings do not solely reflect a reverse pathway. Although pet ownership was strongly associated with the presence of certain genera in the dust for dogs (Agrococcus, Carnobacterium, Exiguobacterium, Herbaspirillum, Leifsonia and Neisseria) and cats (Escherichia), no clear patterns were observed in the NMDS-resolved stool community profiles as a function of pet ownership.

Chromosomal location of structural genes encoding murine immunoglobulin lambda light chains. Genetics of murine lambda light chains.

To determine the chromosomal localization of murine lambda light (L) chain structural genes, DNA from a panel of 11 mouse x hamster somatic cell hybrids was scored for the presence of sequences homologous to cloned lambda DNA probe molecules. Six of the hybrids had detectable lambda I and lambda II gene sequences. In all six, the full complement of murine sequences was present, and in its germline configuration. The remaining hybrids lacked any detectable murine lambda L chain gene sequences. The only mouse chromosome present in all of the positive hybrids and absent from the negative ones was number 16, allowing the assignment of lambda L chain structural genes to this chromosome. Together with the previous assignments of the kappa L chain genes to chromosome 6 and heavy chain genes to chromosome 12, this finding completes the mapping of Ig structural genes in the mouse at the chromosomal level.

Simultaneous analysis of surface marker expression and cell cycle progression in human peripheral blood mononuclear cells.

One method for examining cell cycle kinetics by flow cytometry uses continuous DNA labeling with bromodeoxyuridine (BrdU), a thymidine analogue. Upon incorporation into DNA, BrdU causes stoichiometric quenching of the DNA fluorochrome Hoechst 33258. After counterstaining with a secondary DNA fluorochrome (e.g., ethidium bromide), the analyst can distinguish cells in different phases of the cell cycle over a number of mitotic cycles with flow cytometry. In this report, we describe a modification of the flow cytometric BrdU-Hoechst assay that allows combined analysis of cell proliferation and immunophenotyping at the single cell level. To demonstrate an application of this method, human peripheral blood mononuclear cells were stimulated with tetanus toxoid or interleukin-2 for up to 6 days in the presence of BrdU, harvested, and immunostained for the cell surface markers CD3, CD4, CD8, CD14, CD19, and the cytokine receptor, CCR5. We used four-color flow cytometry analyses to simultaneously measure cell proliferation and surface marker expression, for the purpose of immunophenotyping and identifying specific cell subsets responding to antigen stimulation. Our successful application of this method suggests that it may be used to study immune responses at the molecular and cellular level and to identify mechanisms of immune system modulation.

Characteristics and outcome of medical nonadherers in the Veterans Administration Cooperative Study of Coronary Artery Surgery.

During a 7-year follow-up period in the Veterans Administration Study of Bypass Surgery, 75 (24%) of 311 medically assigned patients without left main disease "crossed over" to surgical treatment. Nineteen baseline, clinical, electrocardiographic and angiographic characteristics of the 75 crossover patients were compared with those of the 236 patients who adhered to medical treatment. At entry into the study, the crossover group contained more patients with severe angina than did the medical adherers group (p less than 0.05) and fewer patients with electrocardiographic evidence of previous myocardial infarction (p less than 0.05). Other entry characteristics were similar in distribution among those in the medical-adherer and crossover groups. The 2 major reasons for crossover were persistence or progression of angina, which occurred in 43 and 37% of the 75 crossover patients, respectively. There was no relation between progression of symptoms and angiographic progression of coronary narrowing. Thus, crossover was not determined by more severe coronary narrowing, but was associated with more severe symptoms and a lower incidence of infarction. The medically randomized patients who later underwent surgery (medical "nonadherers") experienced the same relief of angina 1 year after surgery as did the surgically randomized patients who initially received surgery (surgical "adherers"); however, their overall 7-year survival was lower (77% for medical nonadherers vs 83% for surgical adherers; difference not significant).

Five-year effect of medical and surgical therapy on resting left ventricular function in stable angina: Veterans Administration Cooperative Study.

The effect of coronary artery bypass grafting (CABG) and medical therapy on 5-year resting left ventricular (LV) function was studied in 194 randomized patients with stable angina in the Veterans Administration Study of Coronary Artery Bypass Surgery. LV ejection fraction (EF) was determined in a central laboratory. The 92 medical and 102 surgical patients were comparable at entry with respect to historic, angiographic and electrocardiographic prognostic indicators. Twenty-eight percent of the medical and 30% of the surgical patients had a baseline EF of less than 50%. There was no significant change in mean EF between baseline and 5-year values in either treatment group. The baseline and 5-year values were 56 and 58% in each treatment group. Intervening myocardial infarction (MI) had an adverse effect in medically treated patients (59 to 46%, p less than 0.01) and in surgically treated patients with late MI (58 to 47%, difference not significant). Perioperative MI was not associated with a decrease in EF (56 to 58%, difference not significant). These findings extend the similar results of previous short-term studies of the effect of coronary bypass surgery on resting LV function to 5 years, and provide data in a comparable medical control group.

Physiologic effects of the position of the body in experimental unilateral emphysema.

The functional residual capacity (FRC), static compliance (Cst) of the respiratory system, minute ventilation, and arterial blood gas levels were studied in the prone, the suprine, and the right and left lateral decubitus positions in dogs with papain-induced emphysema of the right lung alone and were compared with control values. The FRC and Cst of the respiratory system were significantly increased in experimental animals in all four positions, as compared with controls. This was due entirely to increases in FRC and Cst for the right lung alone; for the unexposed left lung the FRC and Cst were significantly reduced, as compared to controls. The mean arterial oxygen tension (PaO2) was decreased in all positions, except the right lateral decubitus position, in which the mean PaO2 was not different from controls. This model demonstrates that in unilaterally distributed, experimentally induced emphysema, alterations alterations in the position of the body alone may significantly alter the FRC, Cst, and gas exchange either favorably or unfavorably, depending upon the position.

Iatrogenic coronary artery stenosis following aortic valve replacement.

Until recnetly, coronary arterial perfusion was one of the best methods to protect myocardium during aortic valve replacement. However, the insertion of perfusion cannulas may produce immediate traumatic lesions and late stenosis of the coronary arteries, with grave consequences. Two patients with normal coronary arteries prior to operation developed obstruction of the maximal left main coronary artery following aortic replacement. One of these patients represents the first case of iatrogenic coronary arterial stenosis in which the aortic valve was replaced with a porcine bioprosthesis. Accelerating angina pectoris and ventricular arrhythmias were the presenting clinical manifestations. Aorta-coronary bypass grafting to the left anterior descending and circumflex coronary arteries was successfully performed in one patient, while the other patient died before investigative procedures could be undertaken. Any patient whose aortic valve has been replaced and who develops angina pectoris a few months after operation should be suspected of having developed stenosis of the proximal coronary artery. Coronary angiography should be perfomed promptly. Once the lesion is recognized, the operaiton should be performed posthaste because these lesions are life threatening owing to their proximal location and rapid evolution.

Extrathoracic bypass for stenosis of innominate artery.

Stenosis of the innominate artery usually occurs in older patients in whom the risks of conventional, corrective procedures such as transthoracic endarterectomy or aorto-innominate arterial bypass grafting are quite high. An axillo-axillary bypass procedure was performed in a high-risk patient with innominate arterial stenosis who had repeated episodes of transient cerebral ischemia due to decreased blood flow through the right carotid artery and reversal of blood flow through the right vertebral artery. Postoperatively, he has had dramatic improvement in his symptoms. Because of its simplicity, avoidance of major thoracotomy, avoidance of temporary occlusion of the carotid artery, and excellent late results, axillo-axillary bypass grafting is being proposed as the procedure of choice for stenosis of the innominate artery.

Management of coarctation with multiple calcified aneurysms of the intercostal arteries in adults.

Coarctation of the aorta in adult patients carries an increased but acceptable surgical risk. Our experience emphasizes the technical advantage of an alternative, simpler surgical procedure, such as bypass grafting between the subclavian artery and descending aorta, when one is faced with a friable aorta and concomitant large aneurysms of the intercostal arteries.

Acute and subacute effects of injury on the canine alveolar septum.

The effect of papain on the prevalence and distribution of alveolar macrophages, alveolar septal interstitial tissue gaps and epithelial cells in normal canine pulmonary alveoli was studied by light and electron microscopy. Serial sections of whole alveoli from control animals and from animals sacrificed 4 h, two weeks and one month after the instillation into one lung of crude papain in saline solution containing India ink as a marker were compared. In dogs, as in humans, there is normally a zonal distribution of alveolar macrophages and type 2 cells at alveolar junctional sites. We hypothesize that early alveolar septal injury takes place at these junctional sites, judging from concentration of alveolar macrophages and interstitial septal gaps at these sites following papain exposure, and also that septal repair activities are greatest at these sites, in view of the preponderance and high prevalence of type 2 cells occupying interstitial septal gaps in junctional zones. Consequently, the type 2 cell may play a role beyond that of merely replacing type 1 epithelial cells following alveolar septal injury.

Survival of men treated for chronic stable angina pectoris. A cooperative randomized study.

During 1972 to 1974, 686 men aged 27 to 67 years, admitted to thirteen Veterans Administration Hospitals with stable angina, resting or exercise electrocardiographic abnormalities, "graftable" arteries, and abnormal left ventricular function (80 percent) were randomly assigned to surgery (332) or medical (354) treatment. There was no significant difference in clinical, angiographic, and ventriculographic characteristics. The over-all operative mortality rate (30 days) was 5.8 percent, 5 percent in the 95 percent who had saphenous vein aorta-coronary bypass alone. Eighty-nine percent of the 79 percent recatheterized at 1 year had at least one patent graft. Longevity for patients with one, two, and three vessel disease who were treated surgically was comparable to that previously described, but did not differ from that of the medically treated groups. Survival in the over-all surgical group was 86 percent at 4 years as compared to 83 percent in the medical group, which in these "operative candidates" is better than usually cited. This difference was eliminated when the 90 patients (13 percent) with left main disease, whose longevity was significantly improved (p = 0.005) by the operation, were excluded. Despite this exclusion, a slight trend in favor of surgery was still discernible in the largest subgroup, those having triple vessel disease with an abnormal left ventricle.

Multiple-plane angiography for more precise evaluation of aortoiliac disease.

In 14 patients an oblique view of the aotoiliac region was obtained in addition to the conventional anteroposterior view. Angiograms in oblique projections are indicated in the following situations: (1) where the symptoms cannot be explained by the findings on the conventional anteroposterior view (2) where the patient has had previous anoroiliac grafts and has redeveloped ischmic symptoms, and (3) where patients with unilateral limb ischemia due to unilateral aotoiliac occlusive disease are being considered for a femororfemoral bypass graft procedure. In six patients appreciation of the true significance of the suspected occlusive lesion was of great value in planning the proper surgical procedure. In the remaining eight, angiographic corroboraion of the absence of significant occlusive disease was equally helpful in managing the patient's condition. Examples of each group are presented.

Femorofemoral grafts for unilateral occlusion of aortic bifurcation grafts.

Femorofemoral bypass grafts were performed in 10 patients who developed thrombosis of one of the limbs of previously placed aortoiliac or aortofemoral bifurcation grafts. There were no operative deaths or significant postoperative morbidity, and no amputations had to be performed following the bypass. Nine of the 10 patients have patent grafts from 5 to 70 months (average 33 months) following operation. Of these nine, eight are asymptomatic and one has mild claudication on the side of the unoccluded limb. Because of its simplicity, low operative risk, and encouraging late success rate, we feel that femorofemoral bypass grafting for late unilateral occlusion of a prosthetic bifurcation graft is the procedure of choice.

Esophagopleural fistula following pulmonary resection.

The development of esophagopleural fistula following pulmonary resection is an uncommon but serious complication. The fistula may appear either soon after operation, due to direct trauma to the esophagus or to its blood supply during extensive dissection, or later, in association with the development of a bronchopleural fistula and empyema following the pulmonary resection. Treatment of these fistulas is usually complicated, and the recovery period is prolonged. Control of infection, hyperalimentation, obliteration of the empyema space, and closure of the fistula with a muscle or pleural flap are recommended methods of management. The pathogenesis, treatment, results, and prevention of this complication are discussed.

Long-term results of internal mammary artery implantation for coronary artery disease: a controlled trial by the participants of the Veterans Administration Coronary Bypass Surgery Cooperative Study Group.

One hundred forty-six adult men from sixteen Veterans Administration hospitals were entered in a controlled prospective clinical trial. Seventy-one patients were randomly allocated to receive implantation of the internal mammary artery into the left ventricular myocardium for chronic ischemic heart disease with angina pectoris, and 75 were assigned to the control group. The two treatment groups were similar at baseline with respect to sixteen clinical and angiographic factors thought to have prognostic importance. Most of the patients were operated on before 1970. Operative mortality was 12%, and implant patency in 52% of eligible patients studied 1 year after operation was 67%. At the end of follow-up extending up to 12 years (mean, 9.3 years), cumulative survival for both groups was similar. Over half of the patients (58%) had died at the end of 10 years (5% per year). While the hypothesis on which the operation was based appears to be valid, the degree of revascularization achievable in most patients did not affect longevity.

Quality control for cardiac surgery in the Veterans Administration.

The volume of cardiac surgical procedures and the 30-day mortality associated with them were reviewed for the total experience of 72 Veterans Administration medical centers over a 10-year period (1975 to 1984). The total number of cardiopulmonary bypass operations increased from 3,074 in 1975 to 6,455 in 1984, whereas operative mortality declined from 8.3 to 4.7%. Operative mortality associated with isolated valve replacement operations declined from 10.9 to 5.9%. Aortocoronary vein bypass operations, which increased in number from 1,679 to 4,988 over the 10-year period, were associated with an operative mortality of 4.7% in 1975 and 3.6% in 1984. The extent of the patient's disease accounted for most of the operative mortality, but problems related to the adequacy of myocardial protection and the surgical technique were also important factors. These data were compared with similar comprehensive statistics compiled by the New York State Department of Health over a five-year period (1979-1983). Operative mortality rates were quite similar for aortocoronary bypass procedures, mitral valve replacements, and total cardiac operations. However, operative mortality for aortic valve procedures was higher among the Veterans Administration hospitals. In the future, if operative risk factors are clearly defined, a more meaningful comparison of operative mortality among ongoing reviews, such as those being carried out by the Veterans Administration and by New York State, could be used to establish standards of performance for cardiac surgery.