Diverse material properties and morphology of moth proboscises relates to the feeding habits of some macromoth and other lepidopteran lineages.

Insects have evolved unique structures that host a diversity of material and mechanical properties, and the mouthparts (proboscis) of butterflies and moths (Lepidoptera) are no exception. Here, we examined proboscis morphology and material properties from several previously unstudied moth lineages to determine if they relate to flower visiting and non-flower visiting feeding habits. Scanning electron microscopy and three-dimensional imaging were used to study proboscis morphology and assess surface roughness patterns on the galeal surface, respectively. Confocal laser scanning microscopy was used to study patterns of cuticular autofluorescence, which was quantified with colour analysis software. We found that moth proboscises display similar autofluorescent signals and morphological patterns in relation to feeding habits to those previously described for flower and non-flower visiting butterflies. The distal region of proboscises of non-flower visitors is brush-like for augmented capillarity and exhibited blue autofluorescence, indicating the possible presence of resilin and increased flexibility. Flower visitors have smoother proboscises and show red autofluorescence, an indicator of high sclerotization, which is adaptive for floral tube entry. We propose the lepidopteran proboscis as a model structure for understanding how insects have evolved a suite of morphological and material adaptations to overcome the challenges of acquiring fluids from diverse sources.

Assessing the surveillance capability of Canada's national health surveys.

We assessed Canada's national health surveys as surveillance instruments, with emphasis on comparing the temporal structure of data sets with those generated by the US Behavioral Risk Factor Surveillance System (BRFSS). Only the Canadian Tobacco Use Monitoring Survey (CTUMS) has the BRFSS capability to generate continuous, uniform time series with monthly intervals. These time series can offer substantial extra value for retrospective analysis such as program evaluation in addition to surveillance. Expanding CTUMS is a simple option for providing an ongoing, uniform monthly survey instrument for non-tobacco variables. The Canadian Community Health Survey (CCHS) will generate monthly data, and could potentially generate useful continuous time series even though surveys at the health region and provincial levels will alternate annually. Reconfiguring the CCHS, or even implementing a provincial surveillance survey based on the BRFSS model are other viable options, but each option has associated tradeoffs or obstacles.

Shigellosis on Indian reserves in Manitoba, Canada: its relationship to crowded housing, lack of running water, and inadequate sewage disposal.

OBJECTIVES: This study compares incidence and hospitalization rates for shigellosis between Indians and the rest of the population in Manitoba, Canada. It examines the relationship between shigellosis and environmental conditions on reserves. METHODS: Rates were calculated with surveillance data and a survey of environmental infrastructure was done. RESULTS: Indians had shigellosis incidence and hospitalization rates that were 29 and 12 times as high, respectively, as those of the rest of the population. Household crowding, lack of piped water, and inadequate sewage disposal were significantly associated with an increased incidence of shigellosis on reserves. CONCLUSIONS: Many cases of shigellosis may be prevented by improving living conditions on Indian reserves.

Canadian health surveys, 1950 1997.

This paper provides a brief history of Canadian health surveys and a review of health or health-related surveys from the first national household survey in 1950/51 to the present time. Surveys have evolved from collecting information on health care utilization, health status and some risk behaviours to a wider range of health determinants following the 1974 Lalonde report. In addition to the occasional cross-sectional surveys, there are periodic surveys, longitudinal surveys, school-based surveys and surveys based on subgroups in the population or specific topic areas. The survey review is presented in the following four tables: Table 1 summarizes national surveys including such information as the date(s) and frequency of data collection, topic areas, target population, sample size and response rate for each survey; Table 2 provides the same information for provincial surveys; both tables point to Table 3, which supplements the previous information with survey sponsors and contacts; Table 4 provides similar information for commercial surveys. This reference, which will be updated periodically, is intended to act as a source of information and support in the development of new surveys.

Incidence and prevalence of diabetes in Manitoba, 1986-1991.

OBJECTIVE: To estimate the incidence and prevalence of diabetes among adults in Manitoba, Canada, from 1986 to 1991. RESEARCH DESIGN AND METHODS: A population-based database of individuals diagnosed with diabetes (Manitoba Diabetes Database) was created using data from Manitoba Health's comprehensive insurance system. Using this database, estimates of the annual incidence and prevalence of diabetes among Manitoba adults aged > or = 25 years were made for the years 1986-1991. Age-specific and age-adjusted rates were calculated separately for men and women. RESULTS: The prevalence of diabetes in 1991 was 66.9/1,000 among adults > or = 25 years. Between 1986 and 1991 the age-adjusted prevalence rose steadily among both men and women. In 1991, the incidence of diabetes was 5.6/1,000. After an observed decline prior to 1989, the annual incidence of diabetes appears to be relatively stable. CONCLUSIONS: The prevalence of diabetes is increasing steadily despite relatively stable incidence rates. Population-based data are required for projecting future trends and are an important tool for planning the required health resources.

Vaccine and antiviral strategies against infections caused by human immunodeficiency virus.

Human immunodeficiency virus type 1 (HIV-1) has been clearly associated with a variety of new illnesses, including profound immunodeficiency (acquired immune deficiency syndrome [AIDS]), wasting syndromes (formerly termed AIDS-related complex [ARC]) and neurologic syndromes, including neuropathy, myelopathy and encephalopathy (often termed subacute encephalitis or AIDS dementia complex). HIV-1 preferentially infects T lymphocytes by binding to a membrane receptor protein, CD4, associated with helper function. The virus can also attack macrophages and, possibly, other cells such as neuronal cells, colonic epithelial cells and B lymphocytes. Infection of macrophages or monocytes may be involved in neurologic disease. Knowledge about HIV-1 has rapidly increased, and investigators have characterized its structure, ways in which it infects cells, replicates and is cytopathic for certain cells, and how the immune system responds to it. The ideal vaccine would prevent adsorption of the virus into the cell, but it is difficult to develop stable resistance because the virus has many antigenic patterns and mutates frequently. The results of vaccine trials in animals have not been promising, but work is being done with monoclonal antibodies. Antiviral therapies being investigated include those to prevent virus binding and entry, to inhibit reverse transcription, to inhibit the virus's life cycle and to restore immune competence in immunocompromised patients.