An hypoxia-tolerant flatfish: consequences of sustained stress on the slender sole Lyopsetta exilis (Pleuronectidae) in the context of a changing ocean.

Slender sole Lyopsetta exilis is an abundant groundfish on the continental shelf and inner waters of British Columbia, Canada, where it reaches a maximum standard length of 44 cm. Benthic image surveys coupled with oxygen measurements in Saanich Inlet document a dense population in bottom conditions near anoxia (0.03 ml l-1 oxygen) where diel migrating zooplankton intersect the bottom; we confirm this species is a planktivore, which limits its depth range to the base of the migration layer. In a comparison with slender sole from a nearby well-oxygenated habitat, several probable effects of living in severe hypoxia emerge: both sexes are significantly smaller in Saanich and the sex ratio is male-skewed. Otoliths from the Saanich fish were difficult to read due to many checks, but both sexes were smaller at age with the largest female (20 cm) from the hypoxia zone registering 17 years. Hypoxia appears to have a direct consequence on growth despite good food supply in this productive basin. Hyperventilation, a low metabolic rate and a very low critical oxygen tension help this fish regulate oxygen uptake in severely hypoxic conditions; it will be particularly resilient as the incidence of hypoxia increases on the continental shelf. Data from small-mesh bottom-trawl surveys over four decades reveal an increase in mean annual catch per unit effort in southern regions of the province, including the outer shelf and the Strait of Georgia. The California Cooperative Oceanic Fisheries Investigations (CalCOFI) ichthyoplankton database records a general decline in fish larvae on the Oregon-California shelf since 1990, but slender sole larvae are increasing there, as they are in the Strait of Georgia. We project that the slender sole will gain relative benefits in the future warming, deoxygenated northeast Pacific Ocean.

Endocrine abnormalities in HIV-infected women are associated with peak viral load - the Children and Women: AntiRetrovirals and Markers of Aging (CARMA) Cohort.

OBJECTIVES: To investigate the prevalence of endocrine disturbances in a group of HIV-positive (HIV+) women and to identify factors affecting presence of these disorders. To examine specifically whether cellular ageing, as measured by leukocyte telomere length (LTL), is correlated with the presence of endocrine disturbance. DESIGN: A cross-sectional retrospective substudy of an ongoing prospective cohort study. PATIENTS: Adult HIV+ (≥19 years) women enrolled in the CARMA (Children and Women: AntiRetrovirals and Markers of Aging) cohort study (N = 192). Prevalences of T2DM, glucose intolerance, dyslipidaemia, thyroid disorders, adrenal insufficiency, hypogonadism, primary ovarian insufficiency (POI), demographics, HIV and hepatitis C virus (HCV) infection status, baseline LTL, combined antiRetroviral therapy (cART) and substance exposures were collected. Statistical analysis included univariable followed by multivariable Poisson regression and step-wise reduction to refine the multivariable model. RESULTS: Prevalence of any endocrine abnormality was 58% (dyslipidaemia 43%, glucose intolerance/T2DM 13%, thyroid disorders 15%). In multivariable analysis, age was associated with number and type (any, glucose, lipid) of abnormality, while increasing body mass index (BMI) was associated with number of diagnoses and with glucose metabolism disorders. Interestingly, peak HIV pVL ≥100 000 copies/ml was associated with any abnormality, total number of disorders and presence of a thyroid disorder, while any disorder, glucose abnormalities and dyslipidaemia were negatively associated with alcohol use. LTL was not associated with number or type of endocrine abnormalities in this study. CONCLUSION: Further studies examining the relationship between duration and extent of exposure to HIV viraemia in relation to developing abnormal endocrine function are warranted.

Oxygen limitations on marine animal distributions and the collapse of epibenthic community structure during shoaling hypoxia.

Deoxygenation in the global ocean is predicted to induce ecosystem-wide changes. Analysis of multidecadal oxygen time-series projects the northeast Pacific to be a current and future hot spot of oxygen loss. However, the response of marine communities to deoxygenation is unresolved due to the lack of applicable data on component species. We repeated the same benthic transect (n = 10, between 45 and 190 m depths) over 8 years in a seasonally hypoxic fjord using remotely operated vehicles equipped with oxygen sensors to establish the lower oxygen levels at which 26 common epibenthic species can occur in the wild. By timing our surveys to shoaling hypoxia events, we show that fish and crustacean populations persist even in severe hypoxia (<0.5 mL L(-1) ) with no mortality effects but that migration of mobile species occurs. Consequently, the immediate response to hypoxia expansion is the collapse of community structure; normally partitioned distributions of resident species coalesced and localized densities increased. After oxygen renewal and formation of steep oxygen gradients, former ranges re-established. High frequency data from the nearby VENUS subsea observatory show the average oxygen level at our site declined by ~0.05 mL L(-1) year(-1) over the period of our study. The increased annual duration of the hypoxic (<1.4 mL L(-1) ) and severely hypoxic periods appears to reflect the oxygen dynamics demonstrated in offshore source waters and the adjacent Strait of Georgia. Should the current trajectory of oxygen loss continue, community homogenization and reduced suitable habitat may become the dominant state of epibenthic systems in the northeast Pacific. In situ oxygen occurrences were not congruent with lethal and sublethal hypoxia thresholds calculated across the literature for major taxonomic groups indicating that research biases toward laboratory studies on Atlantic species are not globally applicable. Region-specific hypoxia thresholds are necessary to predict future impacts of deoxygenation on marine biodiversity.

Medical students' self-reported preparedness and attitudes in providing care to ethnic minorities.

BACKGROUND: To assess medical students' self-reported preparedness to provide care to ethnic minorities, factors that influence preparedness, and attitudes toward cultural competency training. METHODS: A cross-sectional study, which invited University of British Columbia medical students to participate in a survey on student demographics, knowledge and awareness, preparedness and willingness, and personal attitudes. Of 1024, eligible, 301 students consented to study. RESULTS: Students across all year levels felt significantly less ready to provide care for non-English speaking Chinese patients compared to "any" patients. Proficiency in working with interpreters was correlated with readiness, OR 4.447 (1.606-12.315) along with 3rd and 4th year level in medical school, OR 3.550 (1.378-9.141) and 4.424 (1.577-12.415), respectively. Over 80% of respondents reported interest in learning more about the barriers and possible ways of overcoming them. CONCLUSIONS: More opportunities for cultural competency training in the medical curriculum are warranted and would be welcomed by the students.

High-resolution freshwater dissolved calcium and pH data layers for Canada and the United States.

Freshwater ecosystems are biologically important habitats that provide many ecosystem services. Calcium concentration and pH are two key variables that are linked to multiple chemical processes in these environments, influence the biology of organisms from diverse taxa, and can be important factors affecting the distribution of native and non-native species. However, it can be challenging to obtain high-resolution data for these variables at regional and national scales. To address this data gap, water quality data for lakes and rivers in Canada and the continental USA were compiled and used to generate high-resolution (10 × 10 km) interpolated raster layers, after comparing multiple spatial interpolation approaches. This is the first time that such data have been made available at this scale and resolution, providing a valuable resource for research, including projects evaluating risks from environmental change, pollution, and invasive species. This will aid the development of conservation and management strategies for these vital habitats.

Ocean weather, biological rates, and unexplained global ecological patterns.

As on land, oceans exhibit high temporal and spatial temperature variation. This "ocean weather" contributes to the physiological and ecological processes that ultimately determine the patterns of species distribution and abundance, yet is often unrecognized, especially in tropical oceans. Here, we tested the paradigm of temperature stability in shallow waters (<12.5 m) across different zones of latitude. We collated hundreds of in situ, high temporal-frequency ocean temperature time series globally to produce an intuitive measure of temperature variability, ranging in scale from quarter-diurnal to annual time spans. To estimate organismal sensitivity of ectotherms (i.e. microbes, algae, and animals whose body temperatures depend upon ocean temperature), we computed the corresponding range of biological rates (such as metabolic rate or photosynthesis) for each time span, assuming an exponential relationship. We found that subtropical regions had the broadest temperature ranges at time spans equal to or shorter than a month, while temperate and tropical systems both exhibited narrow (i.e. stable) short-term temperature range estimates. However, temperature-dependent biological rates in tropical regions displayed greater ranges than in temperate systems. Hence, our results suggest that tropical ectotherms may be relatively more sensitive to short-term thermal variability. We also highlight previously unexplained macroecological patterns that may be underpinned by short-term temperature variability.

Bouveret's syndrome: presentation of two cases with review of the literature and development of a surgical treatment strategy.

BACKGROUND: Bouveret's syndrome causes gastric outlet obstruction when a gallstone is impacted in the duodenum or stomach via a bilioenteric fistula. It is a rare condition that causes significant morbidity and mortality and often occurs in the elderly with significant comorbidities. Individual diagnostic and treatment strategies are required for optimal management and outcome. The purpose of this paper is to develop a surgical strategy for optimized individual treatment of Bouveret's syndrome based on the available literature and motivated by our own experience. CASE PRESENTATION: Two cases of Bouveret's syndrome are presented with individual management and restrictive surgical approaches tailored to the condition of the patients and intraoperative findings. CONCLUSIONS: Improved diagnostics and restrictive individual surgical approaches have shown to lower the mortality rates of Bouveret's syndrome. For optimized outcome of the individual patient: The medical and perioperative management and time of surgery are tailored to the condition of the patient. CT-scan is most often required to secure the diagnosis. The surgical approach includes enterolithotomy alone or in combination with simultaneous or subsequent cholecystectomy and fistula repair. Lower overall morbidity and mortality are in favor of restrictive surgical approaches. The surgical strategy is adapted to the intraoperative findings and to the risk for secondary complications vs. the age and comorbidities of the patient.

Toward an atlas of Salish Sea biodiversity: the flora and fauna of Galiano Island, British Columbia, Canada. Part I. Marine zoology.

Background: Based on records dating from 1859 to 2021, we provide an overview of the marine animal diversity reported for Galiano Island, British Columbia, Canada. More than 650 taxa are represented by 20,000 species occurrence records in this curated dataset, which includes dive records documented through the Pacific Marine Life Surveys, museum voucher specimens, ecological data and crowd-sourced observations from the BC Cetacean Sightings Network and iNaturalist. New information: We describe Galiano Island's marine animal diversity in relation to the Salish Sea's overall biodiversity and quantify the proportional contributions of different types of sampling effort to our current local knowledge. Overviews are provided for each taxonomic group in a format intended to be accessible to amateur naturalists interested in furthering research into the region's marine biodiversity. In summary, we find that the Pacific Marine Life Surveys, a regional community science diving initiative, account for 60% of novel records reported for Galiano Island. Voucher specimens account for 19% and crowd-sourced biodiversity data 18% of novel records, respectively, with the remaining 3% of reports coming from other sources. These findings shed light on the complementarity of different types of sampling effort and demonstrate the potential for community science to contribute to the global biodiversity research community. We present a biodiversity informatics framework that is designed to enable these practices by supporting collaboration among researchers and communities in the collection, curation and dissemination of biodiversity data.

Drivers of temporal beta diversity of a benthic community in a seasonally hypoxic fjord.

Global expansion of oxygen-deficient (hypoxic) waters will have detrimental effects on marine life in the Northeast Pacific Ocean (NEP) where some of the largest proportional losses in aerobic habitat are predicted to occur. However, few in situ studies have accounted for the high environmental variability in this region while including natural community-assembly dynamics. Here, we present results from a 14-month deployment of a benthic camera platform tethered to the VENUS cabled observatory in the seasonally hypoxic Saanich Inlet. Our time series continuously recorded natural cycles of deoxygenation and reoxygenation that allowed us to test whether a community from the NEP showed hysteresis in its recovery compared to hypoxia-induced decline, and to address the processes driving temporal beta diversity under variable states of hypoxia. Using high-frequency ecological time series, we reveal (i) differences in the response and recovery of the epibenthic community are rate-limited by recovery of the sessile species assemblage; (ii) both environmental and biological processes influence community assembly patterns at multiple timescales; and (iii) interspecific processes can drive temporal beta diversity in seasonal hypoxia. Ultimately, our results illustrate how different timescale-dependent drivers can influence the response and recovery of a marine habitat under increasing stress from environmental change.

Trophic ecology of glass sponge reefs in the Strait of Georgia, British Columbia.

Sponges link the microbial loop with benthic communities by feeding on bacteria. Glass sponge reefs on the continental shelf of western Canada have extremely high grazing rates, consuming seven times more particulate carbon than can be supplied by vertical flux alone. Unlike many sponges, the reef building species Aphrocallistes vastus has no microbial symbionts and removes little dissolved organic carbon. To determine how reef sponges therefore get enough food to sustain such substantial grazing we measured stable carbon and nitrogen isotope signatures of water, sediment and sponge tissues. To ensure samples were temporally associated, we also studied the duration particles were retained in tissues in controlled feeding studies using microscopic beads and 13C-labeled bacteria. Although fecal pellets were expelled from sponges within 24 hours of feeding, intact bacteria were still found in tissues and sponge tissues retained elevated 13C levels for at least 14 days. These independent lines of evidence suggest that carbon in reef sponge tissues may reflect food consumed from days to weeks earlier. Stable isotope analysis suggests that heterotrophic bacteria ingested by the sponges comes from a confluence of trophic subsidies: from terrestrial and oceanic sources, and also potentially on sediment-borne bacteria resuspended by tidal currents.

Premature Spinal Bone Loss in Women Living with HIV is Associated with Shorter Leukocyte Telomere Length.

With advances in combination antiretroviral therapy (cART), people living with HIV are now surviving to experience aging. Evidence suggests that individuals living with HIV are at greater risk for low bone mineral density (BMD), osteoporosis, and fractures. Better understanding of the pathophysiology of bone health in women living with HIV (WLWH) is important for treatment strategies. The goal of this study was to explore new biological factors linked to low BMD in WLWH. Standardized BMD measures of WLWH were compared to reference values from an unselected population of women from the same geographical region of the same age range. Linear regression analysis was used to assess relationships among health-related characteristics, cellular aging (measured by leukocyte telomere length; LTL), cART, and BMD of WLWH. WLWH (n = 73; mean age 43 ± 9 years) had lower BMD Z-scores at the lumbar spine (LS) (mean difference = -0.39, p < 0.001) and total hip (TH) (-0.29, p = 0.012) relative to controls (n = 290). WLWH between 50 and 60 years (n = 17) had lower Z-scores at the LS (p = 0.008) and TH (p = 0.027) compared to controls (n = 167). Among WLWH, LS BMD was significantly associated with LTL (R² = 0.09, p = 0.009) and BMI (R² = 0.06, p = 0.042). Spinal BMD was adversely affected in WLWH. Reduction of LTL was strongly associated with lower BMD and may relate to its pathophysiology and premature aging in WLWH.

Regional dose metrics as predictors of biochemical failure and local recurrence after low-dose-rate prostate brachytherapy.

PURPOSE/OBJECTIVES: To assess regional dose metrics as predictors of disease relapse after low-dose-rate prostate brachytherapy. METHODS AND MATERIALS: A cohort of 2000 consecutive patients with prostate cancer treated with iodine-125 low-dose-rate prostate brachytherapy monotherapy was implanted between July 1998 and November 2007. Within this group, 89 patients had disease relapse, 13 of whom had local failure by clinical or histopathologic criteria. Postoperative computed tomography scans were available for 96.3% of cases, resulting in a data set composed of 87 relapses (including all 13 local relapses) and 1839 nonrelapsed controls. Using the VariSeed 8.0.2 software, we divided the original prostate contours into four quadrants: anterior-superior (ASQ), posterior-superior, anterior-inferior (AIQ), and posterior-inferior. DVH-derived dosimetric parameters were calculated for the whole prostate and each quadrant. RESULTS: Gleason score, prostate-specific antigen, and the use of androgen-deprivation therapy were predictive of disease relapse in a multivariate Cox model. Whole prostate dose metrics did not predict biochemical or local relapse. Dosimetric coverage was sparsest in the ASQ. Despite low values, dose to the ASQ was not predictive of relapse, nor were doses to the remaining three quadrants. AIQ coverage was predictive of local relapse in multivariate Cox model (p = 0.042). However, the AIQ dose metrics exhibited a large variance and on bootstrap analysis, a p value of <0.05 was seen in only 51% of 1000 iterations. CONCLUSIONS: Consistent with previous reports, whole-prostate dose metrics were not predictive of disease relapse (any) or local relapse in our patients. Although significant ASQ underdosage relative to other prostate regions was observed, ASQ dose coverage did not correlate with relapse.

Virtual reality training versus blended learning of laparoscopic cholecystectomy: a randomized controlled trial with laparoscopic novices.

This study compared virtual reality (VR) training with low cost-blended learning (BL) in a structured training program.Training of laparoscopic skills outside the operating room is mandatory to reduce operative times and risks.Laparoscopy-naïve medical students were randomized in 2 groups stratified for sex. The BL group (n = 42) used E-learning for laparoscopic cholecystectomy (LC) and practiced basic skills with box trainers. The VR group (n = 42) trained basic skills and LC on the LAP Mentor II (Simbionix, Cleveland, OH). Each group trained 3 × 4 hours followed by a knowledge test concerning LC. Blinded raters assessed the operative performance of cadaveric porcine LC using the Objective Structured Assessment of Technical Skills (OSATS). The LC was discontinued when it was not completed within 80 min. Students evaluated their training modality with questionnaires.The VR group completed the LC significantly faster and more often within 80 min than BL (45% v 21%, P = .02). The BL group scored higher than the VR group in the knowledge test (13.3 ±â€Š1.3 vs 11.0 ±â€Š1.7, P < 0.001). Both groups showed equal operative performance of LC in the OSATS score (49.4 ±â€Š10.5 vs 49.7 ±â€Š12.0, P = 0.90). Students generally liked training and felt well prepared for assisting in laparoscopic surgery. The efficiency of the training was judged higher by the VR group than by the BL group.VR and BL can both be applied for training the basics of LC. Multimodality training programs should be developed that combine the advantages of both approaches.

Variations in the management of acute exacerbations of chronic obstructive pulmonary disease.

BACKGROUND: Acute exacerbations of chronic obstructive pulmonary disease (AECOPD) are a significant cause of morbidity and mortality for patients with COPD. AECOPD are the leading cause of hospital admissions in Canada. Although multiple guidelines have been developed for the acute and chronic management of COPD, there are few quality assurance studies investigating adherence to these guidelines. METHODS: A retrospective chart review of all patients admitted to a tertiary care hospital in 2009 for an AECOPD was performed. Using a standardized data abstraction tool, adherence to current guidelines across different physician groups and patient outcomes were assessed. Particular focus was centred on differences in management across physician groups. RESULTS: Overall, 293 patients were evaluated. Of these, 82.6% were treated with one or more chronic COPD medication(s) in the community, with only 17.7% of patients treated with a long-acting inhaled anticholinergic medication. For treatment of AECOPD, 58% of patients received corticosteroids and 84% received antibiotics. Compared with general medicine and the hospitalist service, the respiratory medicine service demonstrated significantly better adherence with current treatment guidelines; however, even this was less than optimal. In addition, there was poor follow-up of patients cared for outside of the respiratory service. CONCLUSIONS: The present study identified significant care gaps in the treatment of patients admitted with AECOPD and on their discharge.