A Preterm Birth Prevention Project in Nova Scotia,Canada

Objective: The Halifax County Preterm Birth Prevention Project was designed to evaluate the effectiveness of a population-based preterm birth (PTB) prevention program in Nova Scotia from January 1995 through June 1997 (n = 10,326). Methods: Preterm birth rates, adjusted for risk status and maternal age, were evaluated over time in Halifax County and compared to non-Halifax County parturients in Nova Scotia. Physician participation was evaluated by means of a mailed survey. Results: There was no appreciable change in the overall (<37 weeks) or early (<34 weeks) PTB rates within or outside Halifax County during the intervention period compared to the preintervention period. Although not significant, the very (<30 weeks) PTB rate in Halifax County decreased by 40% from 0.53 to 0.32%, while outside Halifax County it remained stable (0.43–0.42%). There was a statistically significant decrease in early and very PTB associated with spontaneous labour, as well as an apparent shift in the timing of delivery from very preterm to preterm (30 weeks). Participation among responding physicians was greater for high-risk than low-risk women, but full compliance with project recommendations was low. Conclusion: The overall ineffectiveness of the Halifax County Preterm Birth Prevention Project may reflect the reluctance of practitioners to fully incorporate the recommended prevention strategies into their practice. However, such interventions may reduce the risk of spontaneous early preterm birth.     

Lymphotropism of Merkel cell polyomavirus infection, Nova Scotia, Canada

To test the hypothesis that Merkel cell polyomavirus (MCPyV) can infect cells of the lymphoid system, we analyzed 353 specimens, including 152 non-Hodgkin lymphomas, 44 Hodgkin lymphomas, 110 benign lymph nodes, 27 lymph nodes with metastasis, and 20 extranodal tissue samples. MCPyV DNA was detected by quantitative PCR in 13 (6.6%) of 196 lymphomas, including 5 (20.8%) of 24 chronic lymphocytic leukemia specimens, and in 11 (10%) of 110 benign lymph nodes, including 8 (13.1%) of 61 samples of reactive hyperplasia and 3 (10.3%) of 29 normal lymph nodes. Other samples were MCPyV negative. Sequence analysis of 9 virus-positive samples confirmed the identity of MCPyV; 3 viral strains were represented. Immunohistochemical testing showed that 1 T-cell lymphoma expressed MCPyV T-antigen. These findings suggest that the lymphoid system plays a role in MCPyV infection and may be a site for MCPyV persistence.     

Defining and operationalizing capacity for heart health promotion in Nova Scotia, Canada

This paper presents an operational definition of capacity building for heart health promotion, instruments developed to measure heart health capacity, and baseline results of capacity for 20 organizations. Qualitative and quantitative research methods were used to collect data. Three instruments were developed to measure organizational capacity for heart health promotion: a survey of community agencies involved in heart health, a questionnaire of organizational practices supportive of heart health promotion, and an interview guide that focused on factors influencing heart health promotion. These instruments proved effective and informed the development of a comprehensive framework for heart health promotion.     

Estrogenic compounds in seawater and sediment from Halifax Harbour, Nova Scotia, Canada

Abstract-Samples of seawater and surface sediment were collected from seven locations around Halifax Harbour, Nova Scotia, Canada, and analyzed for the presence of the organic estrogenic contaminants, bisphenol A (BPA), 17beta-estradiol (E2), and 17alpha-ethinylestradiol (EE2). Samples were extracted using solid phase extraction (seawater) or sonication (sediments), followed by fractionation on a two-layer alumina/silica gel column prior to analysis by liquid chromatography-tandem mass spectrometry (LCMS/MS) with negative-ion electrospray ionization. Levels of the three compounds consistently ranked as BPA > E2 > EE2. The least potent compound and plasticizer BPA reached levels of up to 2.6 ng/L in seawater and 9.5 ng/g in sediments; the natural product E2 was detected at concentrations up to 0.57 ng/L and 0.86 ng/g; while the synthetic estrogen EE2 was in most cases below the method detection limit (0.14 ng/L and 0.28 ng/g). The highest levels were observed in the influent of a secondary treatment plant that discharges into the harbor, with concentrations of 32.4 ng/L for BPA and 5.3 ng/L for E2. Overall, the results indicate that these compounds readily associate with suspended particles rather than remaining in the soluble phase. Measurement of the octanol-water partition coefficient (log K(OW)) confirmed these results, with values of 3.41, 3.89, and 4.16 for BPA, E2, and EE2, respectively. Partitioning experiments using spiked field samples further confirmed these findings, with sorption directly related to sediment total organic content and following the order EE2 > E2 > BPA.     

Changes in maternal characteristics in Nova Scotia, Canada from 1988 to 2001

BACKGROUND: Maternal characteristics such as age, parity, smoking status, pre-pregnancy weight and pregnancy weight gain have changed in many industrialized countries in recent years. Many of these changes have not been adequately described at a population level. The purpose of this study was to describe recent trends in selected maternal characteristics in Nova Scotia. METHODS: Data from a population-based perinatal database were used to examine changes in maternal age, parity, smoking, pre-pregnancy weight, delivery weight and pregnancy weight gain among all deliveries between 1988 and 2001. RESULTS: The proportion of deliveries to women > or = 35 years increased by 84% over the study period from 7.0% in 1988-1991 to 12.9% in 1998-2000, while deliveries to women > or = 40 years increased by more than 100%. The number of nulliparous women > or = 35 years also increased significantly. The overall prevalence of smoking decreased from 32.7% in 1988-1991 to 25.1% in 1998-2001, however the prevalence of smoking among women <20 years did not change over the study period and was almost 50%. The proportion of women with a pre-pregnancy weight of > or = 90 kilograms (kg) increased by 165% from 4.1% in 1988-1991 to 10.7% in 1998-2001. The proportion of women with pregnancy weight gain of < 7 kg and > or =18 kg increased by 37% and 13%, respectively. CONCLUSION: Dramatic changes have occurred in several important maternal characteristics and there is evidence of ongoing change. Continuation of these trends is likely to impact on future obstetric practice and perinatal health.     

The Oral Health Status of Recent Immigrants and Refugees in Nova Scotia, Canada

There are no published reports on the oral health status of adult immigrants and refugees in Canada. An oral health interview and clinical oral examination were conducted on 45 recent immigrants and 41 recent Bhutanese refugees, aged 18–67, in Nova Scotia, Canada. Over half (53 %) of the immigrants and 85 % of the refugees had untreated decay. Most (89 % of immigrants; 98 % of refugees) had moderate to severe gingivitis and the majority (73 % of immigrants; 85 % of refugees) had moderate to severe periodontitis. Despite these, 64 % of immigrants and 49 % of refugees rated their oral health as good, very good or excellent, and most believed they did not need fillings or periodontal treatment. Oral disease among the study sample was higher than the Canadian average and there was a striking discrepancy between self-reported and clinically determined need for dental care.     

Characteristics of three acidic lakes in Kejimkujik National Park,Nova Scotia,Canada

This report summarizes a study of the chemical and biological characteristics of three oligotrophic lakes located in a region that receives a moderately acidic precipitation (mean annual pH 4.5–4.6), and a sulfate deposition of about 20 kg/ha/yr. The two brownwater lakes are relatively acidic (pH 4.5 and 4.8), and much of their acidity is attributable to organic anions. The brownwater lakes also have a large concentration of aluminum and iron, but these are bound to dissolved organic matter and are relatively non-toxic to biota.Average phytoplankton production was largest in the clearwater lake. This was due to its relatively deep euphotic zone, since the average unit-volume productivity did not differ much among the lakes. In fact, productivity at light optimum was largest in the most acidic brownwater lake, probably because of its larger phosphorus concentration. The clearwater lake had extensive macrophyte vegetation, which covered its bottom to a depth of 6.5 m. In the brownwater lakes, macrophytes were confined to shallow nearshore water because of the limited water transparency. Zooplankton density and biomass were largest in the most acidic brownwater lake, probably because of allochthonous organic particulates and little fish predation. Benthic invertebrates were abundant in all three lakes, and were dominated by insects, especially Chironomids. Lakes in the study area appear to be sustaining fish populations at more acidic pHs than elsewhere. This may be due to the large concentration of dissolved organic matter in many lakes, which complexes and partially detoxifies metals such as aluminum.     

Physician Recruitment in Rural Canada: Programs in New Brunswick, Newfoundland, and Nova Scotia

This paper examines programs used in the Atlantic provinces of New Brunswick, Newfoundland, and Nova Scotia to recruit and retain physicians in rural areas. The provinces have many similarities but have unique characteristics that have shaped recruitment methods. The total number of physicians in each province has grown at a faster rate than the population. Each has problems attracting physicians to underserved areas, although the magnitude of the problems vary. The data for this paper were gathered from documents available from various agencies in each province and a series of personal interviews conducted in the spring of 1993. The provinces have chosen different avenues in attempting to solve the maldistribution of physician resources, ranging from regulatory methods in New Brunswick to moves in Newfoundland to encourage graduates of the province's medical school to locate in the rural areas and lessen the dependence on foreign medical graduates. Nova Scotia, with fewer areas needing physicians, has been able to focus its efforts on selected locations. Reviewing the methods used in the three provinces provides an insight into the attempts to solve the shortage of physicians in rural areas.     

Cephamycin resistance in clinical isolates and laboratory-derived strains of Escherichia coli, Nova Scotia, Canada

AmpC β-lactamase, altered porins, or both are usually responsible for cefoxitin resistance in Escherichia coli. We examined the relative importance of each. We studied 18 strains of clinical isolates with reduced cefoxitin susceptibility and 10 initially-susceptible strains passaged through cefoxitin-gradient plates. Of 18 wild-resistant strains, 9 had identical promoter mutations (including creation of a consensus 17-bp spacer) and related pulsed-field gel electrophoresis patterns; the other 9 strains were unrelated. Nine strains had attenuator mutations; two strains did not express OmpC or OmpF. After serial passage, 8 of 10 strains developed cefoxitin resistance, none developed promoter or attenuator mutations, 6 lost both the OmpC and OmpF porin proteins, and 1 showed decreased production of both. One strain had neither porin alteration or increased AmpC production. Porin mutants may occur more commonly and be less fit and less inclined to spread or cause disease than strains with increased β-lactamase expression.The development of antibiotic resistance in Escherichia coli has important clinical implications. E. coli is among the most frequently isolated bacterium in a variety of clinical settings. The development of resistance to older agents such as ampicillin and trimethoprim-sulfamethoxazole, as well as the emerging problem of fluoroquinolone resistance, may substantially limit our antibiotic choices (1,2).Although cephamycin-resistant E. coli is relatively uncommon, widespread use of β-lactam antiboties may contribute to the development and spread of these strains. In 1999, Sahm et al. reported that 0.16% of E. coli were resistant to cephamycins (3). At a local level, unpublished data from the Queen Elizabeth II Health Science Centre in Halifax, Nova Scotia indicated that, of the 5,767 strains of E. coli processed from urine samples, 0.4% were cephamycin resistant.All strains of E. coli possess a gene that encodes an AmpC β-lactamase. Usually, almost no β-lactamase is produced because the gene is preceded by a weak promoter and a strong attenuator (4). Surveys of resistance mechanisms in cephamycin-resistant strains have most often identified promoter or attenuator mutations, which results in an up-regulation of AmpC β-lactamase production (5–7). Occasionally, cephamycin-resistant strains bear mobilized β-lactamases derived from bacteria such as Citrobacter feundii (8). In addition, mutation or altered expression of outer membrane proteins constituting porins can also contribute to cephamycin resistance. To our knowledge, no investigators have concurrently looked for alterations in porins in addition to promoter-attenuator mutations. Porin alterations might work together to produce a higher level of resistance. In addition, porin alterations may protect E. coli and allow subsequent selection for promoter and attenuator mutants.We examined E. coli strains collected at our hospital to determine the basis for resistance. In addition, we created cephamycin-resistant strains of E. coli by serial passage on cefoxitin-containing medium to determine which of these two resistance mechanisms was predominant and if our findings were representative of those seen in clinical isolates.     

Health deficiencies in Cape Breton County, Nova Scotia, Canada, 1950-1995.

Cape Breton County contains one of the most polluted areas in North America and is socioeconomically depressed. We evaluated mortality patterns in this area over the past 5 decades, focusing on life expectancy and life loss. Life loss refers to the difference in life expectancy of Cape Breton County residents and all Canadians, and was further broken down into disease-specific components using cause-eliminated life table methods. We observed lags in health of 20 to 25 years for residents of Cape Breton County. Life expectancy in some municipalities of Cape Breton County is reduced by more than 5 years. Life loss for these residents is greater than that of any single cause of death for Canadians. Life loss among Cape Breton County women is primarily attributable to cancer, and, among men, to cardiovascular diseases. Life loss from cancer is higher in the steel-producing communities; whereas life loss from respiratory diseases and lung cancer is higher in the coal mining communities. These (and other) decompositions of life loss disclose patterns in health deficiencies that give rise to etiologic hypotheses and provide clues and directions for prevention and interventions.     

Effect of Inservice Training on Implementation of a Health Curriculum in Nova Scotia, Canada

The effect of different types of inservice training on the degree of implementation of a fourth grade health curriculum in Nova Scotia, Canada, was investigated. Using a quasiexperimental, nonequivalent control group design with posttest only, teachers (N = 41) were assigned to one trial group and two comparison groups. The distal comparison group received no inservice training, the local comparison group received a single session, and the trial group received ongoing, inservice training. The Health Program Component Checklist developed for this study was used to measure implementation. Data were collected by personal interview. Based on the Mann-Whitney U test, a significantly greater degree of implementation occurred in the trial group than in the proximal comparison group, but not the distal comparison group.     

Correlates of mercury in female river otters (Lontra canadensis) from Nova Scotia, Canada

Mercury (Hg) can reach toxic concentrations in aquatic habitats, sometimes as a consequence of human activity. Mercury can have deleterious effects, particularly in piscivorous mammals in which it bioaccumulates. Furs from trapper-provided female otter (Lontra canadensis) carcasses in Nova Scotia were analyzed for total Hg. Concentrations of total Hg in fur samples averaged 25?μg/g dry weight, ranging from 1.4 to 137?μg/g; 20?μg/g is the fur concentration at which toxic effects are expected. Mercury concentrations were greater in otters from watersheds with bedrock substrates known to contain more available Hg, from otters trapped farther inland, and from otters trapped on watersheds with hydroelectric dams. Otter reproductive potential was measured by counting the number of blastocysts in reproductive tracts. Tooth annuli were used to age otters. Reproductive potential was not related to Hg concentration, nor was Hg concentration related to age. In a general linear model, 53% of variation in fur Hg was explained by underlying bedrock, distance from the coast at which otters were trapped, and presence/absence of a hydroelectric dam. The proportion of juveniles in a population did not differ relative to bedrock Hg concentration, but was lower on watersheds with hydroelectric dams. Because we found no evidence of reduced reproductive potential from greater Hg concentrations, the low proportion of juveniles suggests that Hg reduced juvenile survival, although our evidence is circumstantial.