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BACKGROUND: Lyme carditis (LC), an early manifestation of Lyme disease that most commonly presents as high‐degree atrioventricular block (AVB), usually resolves with antibiotic treatment. When LC is not identified as the cause of AVB, a permanent pacemaker may be inappropriately implanted in a reversible cardiac conduction disorder. HYPOTHESIS: The likelihood that a patient's high‐degree AVB is caused by LC can be evaluated by clinical characteristics incorporated into a risk stratification tool. METHODS: A systematic review of all published cases of LC with high‐degree AVB, and five cases from the authors' experience, was conducted. The results informed the development of a new risk stratification tool, the Suspicious Index in LC (SILC) score. The SILC score was then applied to each case included in the review. RESULTS: Of the 88 cases included, 51 (58%) were high‐risk, 31 (35.2%) intermediate‐risk, and 6 (6.8%) low‐risk for LC according to the SILC score (sensitivity 93.2%). For the subset of 32 cases that reported on all SILC variables, 24 (75%) cases were classified as high‐risk, 8 (25%) intermediate‐risk, and 0 low‐risk (sensitivity 100%). Specificity could not be assessed (no control group). Notably, 6 of the 11 patients who received permanent pacemakers had reversal of AVB with antibiotic treatment. CONCLUSION: The SILC risk score and COSTAR mnemonic (constitutional symptoms; outdoor activity; sex = male; tick bite; age

The incidence of Lyme disease, a tick-borne bacterial infection, is dramatically increasing in North America. The diagnosis of Lyme carditis (LC), an early disseminated manifestation of Lyme disease, has important implications for patient management and preventing further extracutaneous complications. High-degree atrioventricular block is the most common presentation of LC, and usually resolves with antibiotic therapy. A systematic approach to the diagnosis of LC in patients with high-degree atrioventricular block will facilitate the identification of this usually transient condition, thus preventing unnecessary implantation of permanent pacemakers in otherwise healthy young individuals.

See related articles at [[www.cmaj.ca/lookup/doi/10.1503/cmaj.191279][2]][2] and [[www.cmaj.ca/lookup/doi/10.1503/cmaj.191194][3]][3] A 56-year-old woman presented to the emergency department with a new well-defined erythematous patch on her right clavicular region ([Figure 1][3]), myalgia and

Lyme carditis (LC) is a manifestation of the early disseminated stage of Lyme disease and often presents as high-degree atrioventricular (AV) block. High-degree AV block in LC can be treated with antibiotics, usually resolving with a highly favorable prognosis, thus preventing the unnecessary implantation of permanent pacemakers. We present a systematic approach to the diagnosis and management of LC that implements the Suspicious Index in Lyme Carditis (SILC) risk stratification score.

We read with interest the paper by Asghar et al. [(1)][1] on gender differences in authorship of cardiology literature. This paper highlights the value of mentorship in promoting gender equity and reported a significant increase in the proportion of female first and senior authors over time. The

Atrial fibrillation (AF) often complicates the course of inherited cardiomyopathies and, in some cases, may be the presenting feature. Each inherited cardiomyopathy has its own peculiar pathogenetic characteristics that can contribute to the development and maintenance of AF. Atrial fibrillation may occur as a consequence of disease-specific defects, non-specific cardiac chamber changes secondary to the primary illness, or a combination thereof. The presence of AF can denote a turning point in the progression of the disease, promoting clinical deterioration and increasing morbidity and mortality. Furthermore, the management of AF can be particularly challenging in patients with inherited cardiomyopathies. In this article, we review the current information on the prevalence, pathophysiology, risk factors, and treatment of AF in three different inherited cardiomyopathies: hypertrophic cardiomyopathy, arrhythmogenic right ventricular dysplasia/cardiomyopathy, familial dilated cardiomyopathy, and left ventricular non-compaction cardiomyopathy.

Because cardiovascular implantable electronic devices are increasingly indicated in older patients, and the burden of cancer is rising with the growth and aging of the world population, the management of patients with cardiac devices who require radiotherapy for cancer treatment is a timely concern. Device malfunctions might occur in as high as 3% of radiotherapy courses, posing a substantial issue in clinical practice. A nonsystematic comprehensive review was undertaken. We searched PubMed and the MEDLINE database for randomized controlled trials, meta-analyses, systematic reviews, observational studies, in vitro / in vivo studies, and case reports. Articles were selected by 2 independent reviewers, and emphasis was given to information of interest to a general medical readership. The pathophysiology and predictors of cardiovascular implantable electronic device malfunction due to radiotherapy are reviewed, recommendations for the management of patients with such devices undergoing radiotherapy are summarized, and the clinical significance and future directions of this field are discussed. Radiotherapy-induced device malfunctions are rare, but because of the potential complications, the development of evidence-based guidelines for the management of patients with cardiovascular implantable electronic devices undergoing radiotherapy is a timely concern.

Yellowfin sole (Limanda aspera), northern rock sole (Lepidopsetta polyxystra), and Alaska plaice (Pleuronectes quadrituberculatus) are valuable flatfishes in the southeastern Bering Sea (EBS) bottom trawl fishery. The northern Bering Sea (NBS) is near their northern distribution limit. We conducted the first assessment of NBS habitat suitability for these benthivorous flatfishes from the perspective of prey availability in 2010. Benthic samples were collected at 12 trawl stations along a meridional transect extending from 60.5°N to 64.5°N east of St. Lawrence Island to characterize the prey environment. Stomach contents from the flatfishes were concomitantly collected to relate diets to prey fields. The diet compositions did not correspond spatially with the infauna communities. The flatfishes elected a prey group regardless of its relative availability. The spatial mismatch between diet and infauna compositions suggests that prey availability was high in the NBS. The flatfishes generally have versatile diets, but they were more selective of their prey here than in the EBS. The biomass and the abundance of the infauna along the transect were comparable with the EBS. Although niche overlap was high in the NBS, competition for food was likely lower than in the EBS because of the lower density of flatfish. The bottom temperatures in the NBS were in the same range as the EBS during the summer of 2010. The NBS appears to be suitable flatfish habitat at least during the summer ice-free period. The effects of climate warming on the prey environment and on the production and distribution of flatfish are complex and difficult to predict, but if the NBS were to shift over time toward milder winter conditions that more resemble the EBS, its suitability as flatfish habitat would presumably increase based on the present prey availability.

Atrial fibrillation (AF) is an important risk factor for ischemic stroke and reported to be associated with severe obstructive sleep apnea (OSA). The aim of this study was to determine the occurrence of new onset AF in patients with severe OSA and no prior history of AF. Prospective observational

The flatfish yellowfin sole (Limanda aspera), northern rock sole (Lepidopsetta polyxystra), and Alaska plaice (Pleuronectes quadrituberculatus) in the southeastern Bering Sea prey mainly on infauna. Spatial correspondence between their stomach contents and infauna assemblages across habitat types was examined to identify indices of prey availability for flatfish habitat characterization and quality assessment. Benthic samples and flatfish stomachs were collected in 2009 near the Alaska Peninsula in the southeastern Bering Sea. Polychaetes and bivalves were the most dominant infauna groups, each comprising 35–60% by weight in each infauna sample. These two were also the only prey groups that frequently averaged > 50% of stomach content by weight. Bivalves dominated the infauna biomass on the relatively sandy inner shelf (0–50 m depth). The muddier middle shelf (50–100 m) had the highest infauna biomass, which was dominated by polychaetes. Diet compositions of the flatfish varied spatially in correspondence with the infauna assemblage. Polychaetes were prevalent in all flatfish diets on the middle shelf, even yellowfin sole whose typical primary prey are amphipods and bivalves. Polychaete-rich habitats are potentially prime for flatfish as polychaetes are readily utilized where available and generally have high nutritional value. Flatfish did not select for specific polychaete taxa, so an index of habitat quality could be based on the biomass of aggregate polychaetes or on dominant polychaete families of the region. Under normal environmental conditions, the three flatfish have slightly-offset spatial distributions, enabling each to utilize different infauna assemblages across the shelf. However, during cold phases in the Bering Sea ecosystem, as when this study was conducted, a cold pool of

© 2017 Osteoarthritis Research Society International Objective Whole-body vibration (WBV) is a popular fitness trend based on claims of increased muscle mass, weight loss and reduced joint pain. Following its original implementation as a treatment to increase bone mass in patients with osteoporosis, WBV has been incorporated into clinical practice for musculoskeletal disorders, including back pain. However, our recent studies revealed damaging effects of WBV on joint health in a murine model. In this report, we examined potential mechanisms underlying disc degeneration following exposure of mice to WBV. Methods Ten-week-old male mice were exposed to WBV (45 Hz, 0.3 g peak acceleration, 30 min/day, 5 days/week) for 4 weeks, 8 weeks, or 4 weeks WBV followed by 4 weeks recovery. Micro-computed tomography (micro-CT), histological, and gene expression analyses were used to assess the effects of WBV on spinal tissues. Results Exposure of mice to 4 or 8 weeks of WBV did not alter total body composition or induce significant changes in vertebral bone density. On the other hand, WBV-induced intervertebral disc (IVD) degeneration, associated with decreased disc height and degenerative changes in the annulus fibrosus (AF) that did not recover within 4 weeks after cessation of WBV. Gene expression analysis showed that WBV for 8 weeks induced expression of Mmp3, Mmp13, and Adamts5 in IVD tissues, changes preceded by increased expression of Il-1β. Conclusions Progressive IVD degeneration induced by WBV was associated with increased expression of Il-1β within the IVD that preceded Mmp and Adamts gene induction. Moreover, WBV-induced IVD degeneration is not reversed following cessation of vibration.

Summary Objective Low-amplitude, high-frequency whole-body vibration (WBV) has been adopted for the treatment of musculoskeletal diseases including osteoarthritis (OA); however, there is limited knowledge of the direct effects of vibration on joint tissues. Our recent studies revealed striking damage to the knee joint following exposure of mice to WBV. The current study examined the effects of WBV on specific compartments of the murine tibiofemoral joint over 8 weeks, including microarchitecture of the tibia, to understand the mechanisms associated with WBV-induced joint damage. Design Ten-week-old male CD-1 mice were exposed to WBV (45 Hz, 0.3 g peak acceleration; 30 min/day, 5 days/week) for 4 weeks, 8 weeks, or 4 weeks WBV followed by 4 weeks recovery. The knee joint was evaluated histologically for tissue damage. Architecture of the subchondral bone plate, subchondral trabecular bone, primary and secondary spongiosa of the tibia was assessed using micro-CT. Results Meniscal tears and focal articular cartilage damage were induced by WBV; the extent of damage increased between 4 and 8-week exposures to WBV. WBV did not alter the subchondral bone plate, or trabecular bone of the tibial spongiosa; however, a transient increase was detected in the subchondral trabecular bone volume and density. Conclusions The lack of WBV-induced changes in the underlying subchondral bone suggests that damage to the articular cartilage may be secondary to the meniscal injury we detected. Our findings underscore the need for further studies to assess the safety of WBV in the human population to avoid long-term joint damage.

Ecological information on the polychaete community may improve habitat descriptions and distribution models of commercially important species that are polychaete-feeders. This study reports on the first new observations in nearly three decades on the polychaete assemblages in the south-eastern Bering Sea. This information was used in an exploratory assessment of the association between polychaete assemblages and environmental variables that define the benthic habitat. The spatial association between polychaete assemblages and groundfish predators was also explored for insight into whether prey assemblages influence predator distribution. Canonical correspondence analysis indicates that surficial sediment is the most important factor in organizing polychaete assemblages, over other common environmental variables such as depth and temperature. Co-correspondence analysis of the distributions of groundfish species and polychaete families does not indicate that predators are associated with specific prey families. Families that are most frequent in stomach contents of some of the fish in the analysis, mainly Maldanidae and Nephtyidae, are widely distributed across the Bering Sea shelf in diverse sediment types, as are the principal polychaete-feeders in the eastern Bering Sea such as Alaska plaice (Pleuronectes quadrituberculatus) and northern rock sole (Lepidopsetta polyxystra).

Yeung, C., and McConnaughey, R. A. 2008. Using acoustic backscatter from a sidescan sonar to explain fish and invertebrate distributions: a case study in Bristol Bay, Alaska. – ICES Journal of Marine Science, 65: 242–254. Environmental variables that are ecologically relevant and easily measured over large areas are useful for modelling species distributions and habitats. Continuous acoustic, sonar-backscatter data convey information about physical properties of the seabed, and hence could be a valuable addition to that suite of variables. We tested the potential utility of acoustic backscatter for improving habitat models of marine species using data from a pilot sidescan-sonar survey. Raw digital-backscatter data were processed with QTC SIDEVIEW and CLAMS software. Resultant acoustic variables—Q-values (Q1, Q2, and Q3), representing the first three principal components of the data derived from image analysis of backscatter echoes, and a complexity metric (compx) measuring the variance of Q-values in a geographic area—were used in multiple linear regression to model individual species abundance from bottom-trawl survey data. Habitat models for flathead sole (Hippoglossoides elassodon), Pacific cod (Gadus macrocephalus), walleye pollock (Theragra chalcogramma), red king crab (Paralithodes camtschaticus), basket star (Gorgonocephalus eucnemis), and sponges (Porifera) included acoustic variables as significant predictors. For these six taxa, full models explained 67–86% of variability in abundance, with 9–54% of that total contributed by the acoustic predictors, suggesting that acoustic data could advance habitat research for some bottom-associated marine species.

Catches of invertebrates from the annual summer bottom-trawl surveys in the eastern Bering Sea between 1982 and 2002 were analyzed to describe the composition and spatial distri- bution of epibenthic invertebrate communities. A persistent characteristic is distinct inshore and offshore community types separated by the dynamic oceanographic inner front that generally co- incides with the 50 m isobath. This typical spatial distribution of the 2 communities corresponds closely with surficial sediment type and previously reported patterns for groundfishes and infaunal invertebrates. The biomass of the inshore assemblage is overwhelmingly dominated by the sea star Asterias amurensis, whereas Gastropoda, Paguridae and the snow crab Chionoecetes opilio domi- nate the offshore assemblage. Variations in the typical inshore- offshore pattern occurred in 1982- 84, 1987- 88, 1998- 99 and 2001- 02, when there were substantial reductions in the spatial extent of the inshore community, especially in the Bristol Bay area. During these reductions, epiben- thos in Bristol Bay shifted from the inshore type to either offshore or an undefined community type. In general, reductions in the inshore domain were correlated with a mean bottom temperature in the survey area that was higher than normal in the preceding summer. Extreme El Nino events coincided with sizable contractions of the inshore community in 1982- 84 and 1998- 99. Spatial variability in the epibenthic communities may thus reflect the influence of environmental changes on interannual and decadal scales. Evidence suggests that mobile taxa, especially crabs, may be migrating offshore toward cooler waters, thereby rearranging the epibenthic communities.

Pink shrimp ( Farfantepenaeus duorarum ) postlarvae were collected monthly with moored channel nets from October 1997 to June 1999 at Whale Harbor (WH) and Long Key (LK) Channels, two channels at the east and west ends of the Middle Florida Keys that connect the Atlantic Ocean with Florida Bay, the main nursery ground of this species in south Florida. The density influx of pink shrimp postlarvae through these two channels differed in magnitude and seasonal patterns. The monthly influx of postlarvae at LK was lower in magnitude but steadier than at WH. LK showed the highest postlarval influx in late spring–summer. Postlarval influx through WH further downstream showed both spring–summer and winter peaks. The spring–summer peaks correspond with favorable wind and current conditions. In contrast, the winter peaks occurred when cyclonic eddies were detected passing through the Middle Florida Keys. These cyclonic eddies induced coastal countercurrent flow that favors onshore larval transport. The position of the leading edge of the eddy relative to the channels may cause the temporal variability observed in the temporal postlarval influx patterns between channels. A seasonal size variation in postlarvae was also observed at both sampling sites. Postlarvae captured during the winter months were significantly larger than those captured during the summer months. The number of rostral spines, a morphological feature generally correlating with the number of moults and age, also varied seasonally but with a trend opposite to that of the body size, which may indicate a lengthening of the intermoult period during wintertime. The reasons for the seasonal differences in growth rates and, possibly, different lengths of time in the currents, are yet to be resolved.

The spiny lobster Panulirus argus is of ecological and commercial importance in the South Florida coast of the continental USA and throughout the Intra-Americas Sea. Essential spiny lobster habitat in South Florida is primarily located in the Florida Keys coastal zone (including the Dry Tortugas), where the dynamic regional circulation coupled with the long planktonic larval duration (6–12 months) of P. argus raises questions of larval retention and recruitment. Locally spawned phyllosomata entrained in the Florida Current are likely to be expatriated out of the Straits of Florida, which implies that the local spiny lobster population is sustained by the transport of larval recruits from upstream locations. We examined the physical processes that may influence recruitment. Transport processes in the Keys coastal zone are spatially variable. Observed and modelled data suggest that the upper Keys is a point of onshore larval transport via the inshore meandering of the Florida Current, and the lower Keys to Dry Tortugas region apoint of retention through wind-driven onshore/countercurrents and eddy recirculation. Eddies that propagate between the Dry Tortugas and the lower Keys facilitate the exchange of larvae between the Florida Current and the coastal zone. Northerly wind events associated with cold fronts can enhance recirculation of larvae in the upper Keys. The association of older larvae with the Florida Current front supports the hypothesis that spiny lobster larval recruits come from upstream sources in the Caribbean.

A massive intrusion of low-salinity water (salinity = 31–35) from the Mississippi River to the Florida Keys in September 1993 coincided with an unusual abundance of the phyllosoma larvae (stages IV–VII) of a slipper lobster, Scyllarides nodifer, and the zoeae (stages III–V) of a sand crab, Albunea sp. These species are abundant in the northeastern Gulf of Mexico, but their adults and early stage larvae are not common in the Florida Keys. The influx of S. nodifer and Albunea sp. larvae into the Florida Keys is believed to have originated on the northeastern Gulf of Mexico shelf. The southward transport of the larvae within a low-salinity plume from the Mississippi River was apparently caused by anomalous eastward winds moving shelf waters into the Loop Current, which had extended to within ∼170 km of the Mississippi Delta. During normal-salinity conditions (salinity > 36) the spiny lobster Panulirus argus is the most numerous species of phyllosoma larvae in the coastal waters of the Florida Keys. A wide range of stages of P. argus is present year-round in the Florida Keys, suggesting multiple larval sources upstream possibly in the Yucatan Peninsula and the Caribbean. In contrast, the source of S. nodifer and Albunea sp. recruits for the Florida Keys may lie principally in the northeastern gulf. The recruitment success of larvae of gulf origin to the Florida Keys may depend partly on the coincidence of specific wind and Loop Current transport conditions with an availability of larvae for expatriation at the source.

In insects, the excretory system is comprised of the Malpighian tubules (MTs) and the hindgut, which collectively function to maintain ionic and osmotic balance of the haemolymph and rid the organism of toxic compounds or elements in excess. Secretion by the Malpighian tubules of insects is regulated by a variety of hormones including peptidergic factors as well as biogenic amines. In Rhodnius prolixus, two endogenous diuretic hormones have been identified; the biogenic amine serotonin (5-hydroxytryptamine, 5-HT) and the corticotropin releasing factor-related peptide, RhoprCRF. Both factors significantly increase secretion by MTs and are known to elevate intracellular levels of cAMP. Interestingly, applying sub-maximal doses of these two diuretic factors in combination on isolated MTs in vitro reveals synergistic effects as rates of fluid secretion are significantly higher than would be expected if rates of secretion from MTs treated with each factor alone were summed. This observed synergism suggests that different downstream targets may be activated by the two diuretic factors, but that some cellular elicitors may be shared since cAMP is elevated in response to either diuretic hormone. This study investigated the signaling cascade involved in the diuretic hormone regulation of Malpighian tubule fluid secretion. Bioassays were performed in physiological as well as modified salines (e.g. calcium-free) alone or in the presence of a variety of pharmacological compounds that interfere with prospective intracellular targets, such as the apical cation/H+ exchanger. Intriguingly, only amiloride yielded differential effects on the two diuretics with 5HT-stimulated secretion being blocked, whereas in contrast, RhoprCRF-stimulated secretion was unaffected. In addition, experiments examining the role of extracellular and intracellular calcium on fluid secretion rate showed that both diuretics are dependent on intracellular calcium availability. Finally, fluid secretion stimulated by either diuretic hormone was also sensitive to inhibition of cAMP-dependent protein kinase A. Taken together, these results suggest that each diuretic hormone activates pathways dependent upon intracellular calcium and cAMP.

Postlarvae of the spiny lobster Panulirus argus migrate from offshore in the Florida Keys into their juvenile habitat in Florida Bay through interisland channels. The influx of postlarvae was monitored monthly over the new-moon period at Long Key and Whale Harbor channels (July 1997–June 1999). Although the channels were only 30 km apart, their influx patterns differed. At Long Key, influx peaked every 2–3 months, whereas at Whale Harbor the peaks were in winter and of higher magnitudes. The influx pattern at Long Key was highly correlated with the strength of coastal counter-current flow in the two-week period prior to sampling. Countercurrent flow was correlated with alongshore (upstream) wind stress, but the latter was not a significant predictor of postlarval influx. Coastal counter-current flow is hypothesized to indicate the presence of a cyclonic, mesoscale eddy offshore. Satellite imagery confirmed the presence of these eddies offshore of the Middle Florida Keys often when positive postlarval influx and counter-current anomalies were observed. These eddies can facilitate onshore larval transport, and their variable temporal and spatial properties can cause transport variability over a scale of several tens of kilometres along the Keys.