Neighborhood context and ethnicity differences in body mass index: a multilevel analysis using the NHANES III survey (1988-1994).

A growing body of literature has documented a link between neighborhood context and health outcomes. However, little is known about the relationship between neighborhood context and body mass index (BMI) or whether the association between neighborhood context and BMI differs by ethnicity. This paper investigates several neighborhood characteristics as potential explanatory factors for the variation of BMI across the United States; further, this paper explores to what extent segregation and the concentration of disadvantage across neighborhoods help explain ethnic disparities in BMI. Using data geo-coded at the census tract-level and linked with individual-level data from the Third National Health and Examination Survey in the United States (U.S.), we find significant variation in BMI across U.S. neighborhoods. In addition, neighborhood characteristics have a significant association with body mass and partially explain ethnic disparities in BMI, net of individual-level adjustments. These data also reveal evidence that ethnic enclaves are not in fact advantageous for the body mass index of Hispanics-a relationship counter to what has been documented for other health outcomes.     

Behavioral Responses of Gorillas to Habituation in the Dzanga-Ndoki National Park,Central African Republic

We monitored the impact of habituation for tourism through changes in gorillas' behavior during the habituation process at Bai Hokou (Dzanga-Ndoki National Park, Central African Republic) from August 1996 to December 1999. From August 1998 onwards we focused on one gorilla group: the Munye. During the habituation process, it became increasingly easier to locate and to remain with the gorillas. Their initial reactions of aggression, fear and vocalization upon contact were replaced increasingly by ignoring us. Curiosity appeared to be an intermediate stage in the process. The way in which contacts with the Munye ended became more subdued over time. Regular daily contact is important in promoting habituation. Likewise, contacting gorillas while they are in a tree or in dense forest provides positive results compared to open habitat. Contacts within 10 m and contacts without forewarning the gorillas of observer presence, e.g., via tongue clacking, should be avoided. As of December 1999, habituation had progressed well; habituation of western gorillas is feasible. However, the gorillas experience negative effects during the habituation process, showing, for example, an increase in daily path length, and reactions of aggression, fear and vocalization upon contact. Impacts diminish over time. Given these and other potentially negative effects, the decision to begin habituation should not be taken lightly.     

Latest Pleistocene—Holocene paleoceanographic trends on the continental margin of eastern Canada: Foraminiferal,dinoflagellate and pollen evidence

Micropaleontological studies were made of cores from four shelf basins on the eastern Canadian Margin: Emerald and Canso basins on the Scotian Shelf (44°–46° N), Notre Dame Channel, Newfoundland Shelf (50° N) and Cartwright Saddle, Labrador Shelf (55°). Events were correlated using a combination of¹⁴C dates and pollen stratigraphies. Surface- and bottom-water changes were compared on the basis of dinoflagellates and benthic foraminifera, respectively. The results indicate significant paleoceanographic shifts along a north—south gradient both prior to and during the Holocene.Distinct Late Pleistocene—Holocene paleoceanographic events were distinguished in the Emerald, Canso and Notre Dame basins; these events are less obvious in Cartwright Saddle which is in deeper water and further off-shore. Pleistocene glaciomarine sediments in all basins contain a fauna dominated byElphidium excavatum f.clavata; dinoflagellates and pollen are rare or absent. The widespreadElphidium fauna probably reflects turbid glacial meltwater and/or a permanent ice shelf cover from 20,000-10,000 yrs BP. The Notre Dame core also penetrates older sediment with an outer Labrador Current fauna which may represent a late Wisconsinian interstade at about 23,000 yrs BP. From 7,000–10,000 yrs BP a cold water fauna occurred which is similar to modern outer Labrador Current faunas. From about 5000–7000 yrs BP, a warm interval is indicated by a relatively warm-water calcareous benthonic foraminiferal fauna and increased representation of typical Gulf Stream dinoflagellates. The most recent change occurred in the last 2000 years with an abrupt cooling associated with stronger flow of the arctic inner Labrador Current. This cooling event is marked by an increase in arctic dinoflagellates and by an exclusively agglutinated benthonic foraminiferal fauna at two sites (Canso and Notre Dame). These Holocene paleoceanographic changes are not clearly seen in the benthic fauna of the deep northern basin (Cartwright Saddle) although dinoflagellate data at this site indicate that surface-water changes have occurred that are similar to those found in shallower basins.Shifts in the zonal position of the Gulf Stream and changes in the relative mass transports of the West Greenland and Labrador currents are mechanisms which may account for the paleoceanographic events. The glacial—interstadial—glacial sequence recorded in the Notre Dame Channel, in conjunction with other theories on glacial triggering mechanisms, provides biostratigraphic evidence which suggests the onset of a glacial stage in the near future.     

Glucose-limiting conditions induce an invasive population of MDA-MB-231 breast cancer cells with increased connexin 43 expression and membrane localization

Gap junctional intercellular communication (GJIC) is a homeostatic process mediated by membrane channels composed of a protein family known as connexins. Alterations to channel activity can modulate suppression or facilitation of cancer progression. These varying roles are influenced by the cancer cell genetic profile and the context-dependent mechanisms of a dynamic extracellular environment that encompasses fluctuations to nutrient availability. To better explore the effects of altered cellular metabolism on GJIC in breast cancer, we generated a derivative of the triple-negative breast cancer cell line MDA-MB-231 optimized for growth in low-glucose. Reduced availability of glucose is commonly encountered during tumor development and leads to metabolic reprogramming in cancer cells. MDA-MB-231 low-glucose adapted cells exhibited a larger size with improved cell–cell contact and upregulation of cadherin-11. Additionally, increased protein levels of connexin 43 and greater plasma membrane localization were observed with a corresponding improvement in GJIC activity compared to the parental cell line. Since GJIC has been shown to affect cellular invasion in multiple cancer cell types, we evaluated the invasive qualities of these cells using multiple three-dimensional Matrigel growth models. Results of these experiments demonstrated a significantly more invasive phenotype. Moreover, a decrease in invasion was noted when GJIC was inhibited. Our results indicate a potential response of triple-negative breast cancer cells to reduced glucose availability that results in changes to GJIC and invasiveness. Delineation of this relationship may help elucidate mechanisms by which altered cancer cell metabolism affects GJIC and how cancer cells respond to nutrient availability in this regard. Supplementary materialThe online version of this article (10.1007/s12079-020-00601-3) contains supplementary material, which is available to authorized users.     

Terrestrial Tree Hugging in a Primarily Arboreal Lemur (Propithecus verreauxi): a Cool Way to Deal with Heat?

International Journal of Primatology - High temperatures pose a significant risk to mammals, especially those living in hot and dry environments such as southern Madagascar, the location of...     

Risk factors for outbreaks of SARS-CoV-2 infection at retirement homes in Ontario,Canada: a population-level cohort study

BACKGROUND:The epidemiology of SARS-CoV-2 infection in retirement homes (also known as assisted living facilities) is largely unknown. We examined the association between home-and community-level characteristics and the risk of outbreaks of SARS-CoV-2 infection in retirement homes since the beginning of the first wave of the COVID-19 pandemic.METHODS:We conducted a population-based, retrospective cohort study of licensed retirement homes in Ontario, Canada, from Mar. 1 to Dec. 18, 2020. Our primary outcome was an outbreak of SARS-CoV-2 infection (≥ 1 resident or staff case confirmed by validated nucleic acid amplification assay). We used time-dependent proportional hazards methods to model the associations between retirement home– and community-level characteristics and outbreaks of SARS-CoV-2 infection.RESULTS:Our cohort included all 770 licensed retirement homes in Ontario, which housed 56 491 residents. There were 273 (35.5%) retirement homes with 1 or more outbreaks of SARS-CoV-2 infection, involving 1944 (3.5%) residents and 1101 staff (3.0%). Cases of SARS-CoV-2 infection were distributed unevenly across retirement homes, with 2487 (81.7%) resident and staff cases occurring in 77 (10%) homes. The adjusted hazard of an outbreak of SARS-CoV-2 infection in a retirement home was positively associated with homes that had a large resident capacity, were co-located with a long-term care facility, were part of larger chains, offered many services onsite, saw increases in regional incidence of SARS-CoV-2 infection, and were located in a region with a higher community-level ethnic concentration.INTERPRETATION:Readily identifiable characteristics of retirement homes are independently associated with outbreaks of SARS-CoV-2 infection and can support risk identification and priority for vaccination.

Frail older adults living in congregate care settings have been at the centre of the COVID-19 pandemic in Canada and internationally.^1,2 Long-term care facilities — whose residents are the congregate living population most affected by COVID-19 — have been the subject of immense scientific and public interest during the pandemic.³ Retirement homes (often known as assisted living facilities) have received far less examination despite also housing many vulnerable older adults.^4–7 In contrast to long-term care facilities, retirement homes are private residential complexes that provide a range of supportive care and lifestyle services that are purchased out of pocket by residents or their families.⁸ Although residents of retirement homes access supportive care services, they are substantially less frail and dependent than residents of long-term care homes.⁵ Inconsistent regulation of these facilities throughout Canada and the United States has limited research into the epidemiology of SARS-CoV-2 infection in retirement homes.⁹There are 770 licensed retirement homes in Ontario, Canada’s most populous province, that house more than 50 000 older adults, a population size that approaches the number of Ontario residents of long-term care homes.¹⁰ Since the onset of the COVID-19 pandemic in Ontario, the number of positive cases and deaths in retirement homes has continued to grow. As of Apr. 11, 2021, retirement home residents accounted for about 8% of deaths from COVID-19 in Ontario (596/7552).¹¹ Outbreaks of SARS-CoV-2 infection surged in retirement homes during the first and second waves in Canada and the US,^11,12 and there has been limited examination in the literature beyond early reports of case surveillance.¹³We examined the association between home- and community-level characteristics and the risk of outbreaks of SARS-CoV-2 infection during the first wave of the COVID-19 epidemic in Ontario’s retirement homes. Consistent with our previous population-level work in Ontario long-term care homes,^2,14 we hypothesized that home size and regional incidence of SARS-CoV-2 infection would be associated with the risk of an outbreak.