Recent infective endocarditis research findings suggest dentists prescribe prophylactic antibiotics for patients having a bicuspid aortic valve or mitral valve prolapse.

BACKGROUND: The scientific validity of the European Society of Cardiology's (ESC) infective endocarditis (IE) guidelines limiting provision of prophylactic antibiotics (AP) only to patients having cardiac anomalies (e.g., prosthetic valves) believed to place them at "high risk" of adverse events when undergoing high risk dental procedures (HRDP) is unclear. MATERIAL AND METHODS: A systematic review of studies conducted between 2017 and 2022 and catalogued in the PubMed database was undertaken to ascertain if this edict was associated with changes in IE incidence, development of infection in unprotected cardiac anomalies, developing infection and resultant adverse clinical outcomes. RESULTS: Retrieved were 19 published manuscripts, however of these, 16 were excluded because they did not bare upon the issues of concern. Among the three studies eligible for review were those in the Netherlands, Spain, and England. The results of the Dutch study denoted a significant increase in the incidence of IE cases over the projected historical trend (rate ratio: 1327, 95% CI 1.205-1.462; p<0.001) after the introduction of the ESC guidelines. The findings from the Spanish study evidenced the uniquely high in-hospital IE associated fatality rates suffered by patients having bicuspid aortic valves (BAV); 5.6% or mitral valve prolapse (MVP); 10%. The British study provided evidence that the incidence of fatal IE infection was significantly greater among an "intermediate risk" cohort of patients, (a group likely including those with BAC and MVP for which the ESC guidelines don't recommend AP), than among "high risk" patients (P = 0.002). CONCLUSIONS: Patients having either a BAV or MVP are at significant risk of developing IE and suffering serious sequelae including death. The ESC guidelines must reclassify these specific cardiac anomalies into the "high risk" category so that AP are recognized as being needed prior to provision of HRDP.

Reproductive life history of the introduced peacock grouper Cephalopholis argus in Hawaii.

This research investigated the reproductive biology (sex ratio, hermaphroditic pattern, size and age at maturity) of Cephalopholis argus, known locally in Hawaii by its Tahitian name roi. The results suggest that C. argus exhibits monandric protogyny (female gonad differentiation with female to male sex change) with females reaching sexual maturity at 1.2 years (95% c.i.: 0.6, 1.6) and 20.0 cm total length (LT ; 95% c.i.: 19.6, 21.2). The female to male sex ratio was 3.9:1. The average age and LT at sex change was 11.5 years (95% c.i.: 11.1, 12.9) and 39.9 cm (95% c.i.: 39.5, 41.2), respectively. Current information on spawning seasonality of this species is incomplete, but based on the occurrence of spawning capable and actively spawning females, spawning probably takes place from May to October. Evidence of lunar spawning periodicity was found, with an increased proportion of spawning capable and actively spawning females, and an increased female gonado-somatic index during first quarter and full-moon phases. This information fills a valuable information gap in Hawaii and across the species' native range.

Humans and seasonal climate variability threaten large-bodied coral reef fish with small ranges.

Coral reefs are among the most species-rich and threatened ecosystems on Earth, yet the extent to which human stressors determine species occurrences, compared with biogeography or environmental conditions, remains largely unknown. With ever-increasing human-mediated disturbances on these ecosystems, an important question is not only how many species can inhabit local communities, but also which biological traits determine species that can persist (or not) above particular disturbance thresholds. Here we show that human pressure and seasonal climate variability are disproportionately and negatively associated with the occurrence of large-bodied and geographically small-ranging fishes within local coral reef communities. These species are 67% less likely to occur where human impact and temperature seasonality exceed critical thresholds, such as in the marine biodiversity hotspot: the Coral Triangle. Our results identify the most sensitive species and critical thresholds of human and climatic stressors, providing opportunity for targeted conservation intervention to prevent local extinctions.

Energetic and ecological constraints on population density of reef fishes.

Population ecology has classically focused on pairwise species interactions, hindering the description of general patterns and processes of population abundance at large spatial scales. Here we use the metabolic theory of ecology as a framework to formulate and test a model that yields predictions linking population density to the physiological constraints of body size and temperature on individual metabolism, and the ecological constraints of trophic structure and species richness on energy partitioning among species. Our model was tested by applying Bayesian quantile regression to a comprehensive reef-fish community database, from which we extracted density data for 5609 populations spread across 49 sites around the world. Our results indicate that population density declines markedly with increases in community species richness and that, after accounting for richness, energetic constraints are manifested most strongly for the most abundant species, which generally are of small body size and occupy lower trophic groups. Overall, our findings suggest that, at the global scale, factors associated with community species richness are the major drivers of variation in population density. Given that populations of species-rich tropical systems exhibit markedly lower maximum densities, they may be particularly susceptible to stochastic extinction.

Detection of carotid artery calcification on the panoramic images of post-menopausal females is significantly associated with severe abdominal aortic calcification: a risk indicator of future adverse vascular events.

OBJECTIVES: Outcome studies among post-menopausal females with calcified carotid artery plaque (CCAP) on their panoramic images have not been previously undertaken. We sought to compare the extent of abdominal aortic calcification (AAC) on lateral lumbar spine radiographs (LLSRs), among groups of females with (CCAP+) and without (CCAP-) carotid lesions on their panoramic images. "Severe" levels of AAC have previously been validated as a risk indicator of future adverse cardiovascular events. METHODS: This cross-sectional case-control study included a "CCAP+ group" consisting of females more than 50 years of age having the carotid lesion diagnosed by their dentists and an atherogenic risk factor (age, body mass index, hypertension, diabetes and dyslipidaemia)-matched "CCAP- group". A physician radiologist, using the Framingham index, evaluated the LLSRs for the magnitude of AAC. Summary statistics for key variables were computed and conditional logistic regression techniques were considered. RESULTS: Members of the CCAP+ group were significantly (p=0.038) more likely to demonstrate "severe" levels of AAC on their LLSRs than members of the CCAP group. CONCLUSIONS: This is the first published study demonstrating that CCAP on panoramic images of post-menopausal females is significantly associated with "severe" levels of AACs on LLSRs independent of traditional risk factors. Given that these levels of AAC are a validated risk indicator of future myocardial infarction and stroke, dentists must evaluate the panoramic images of post-menopausal females for the presence of CCAP. Patients with carotid atheromas should be referred to their physicians for further evaluation given the systemic implications.

Scaling metabolism from individuals to reef-fish communities at broad spatial scales.

Fishes contribute substantially to energy and nutrient fluxes in reef ecosystems, but quantifying these roles is challenging. Here, we do so by synthesising a large compilation of fish metabolic-rate data with a comprehensive database on reef-fish community abundance and biomass. Individual-level analyses support predictions of Metabolic Theory after accounting for significant family-level variation, and indicate that some tropical reef fishes may already be experiencing thermal regimes at or near their temperature optima. Community-level analyses indicate that total estimated respiratory fluxes of reef-fish communities increase on average ~2-fold from 22 to 28 °C. Comparisons of estimated fluxes among trophic groups highlight striking differences in resource use by communities in different regions, perhaps partly reflecting distinct evolutionary histories, and support the hypothesis that piscivores receive substantial energy subsidies from outside reefs. Our study demonstrates one approach to synthesising individual- and community-level data to establish broad-scale trends in contributions of biota to ecosystem dynamics.

Global assessment of the status of coral reef herbivorous fishes: evidence for fishing effects.

On coral reefs, herbivorous fishes consume benthic primary producers and regulate competition between fleshy algae and reef-building corals. Many of these species are also important fishery targets, yet little is known about their global status. Using a large-scale synthesis of peer-reviewed and unpublished data, we examine variability in abundance and biomass of herbivorous reef fishes and explore evidence for fishing impacts globally and within regions. We show that biomass is more than twice as high in locations not accessible to fisheries relative to fisheries-accessible locations. Although there are large biogeographic differences in total biomass, the effects of fishing are consistent in nearly all regions. We also show that exposure to fishing alters the structure of the herbivore community by disproportionately reducing biomass of large-bodied functional groups (scraper/excavators, browsers, grazer/detritivores), while increasing biomass and abundance of territorial algal-farming damselfishes (Pomacentridae). The browser functional group that consumes macroalgae and can help to prevent coral-macroalgal phase shifts appears to be most susceptible to fishing. This fishing down the herbivore guild probably alters the effectiveness of these fishes in regulating algal abundance on reefs. Finally, data from remote and unfished locations provide important baselines for setting management and conservation targets for this important group of fishes.

From principles to practice: a spatial approach to systematic conservation planning in the deep sea.

Increases in the demand and price for industrial metals, combined with advances in technological capabilities have now made deep-sea mining more feasible and economically viable. In order to balance economic interests with the conservation of abyssal plain ecosystems, it is becoming increasingly important to develop a systematic approach to spatial management and zoning of the deep sea. Here, we describe an expert-driven systematic conservation planning process applied to inform science-based recommendations to the International Seabed Authority for a system of deep-sea marine protected areas (MPAs) to safeguard biodiversity and ecosystem function in an abyssal Pacific region targeted for nodule mining (e.g. the Clarion-Clipperton fracture zone, CCZ). Our use of geospatial analysis and expert opinion in forming the recommendations allowed us to stratify the proposed network by biophysical gradients, maximize the number of biologically unique seamounts within each subregion, and minimize socioeconomic impacts. The resulting proposal for an MPA network (nine replicate 400 × 400 km MPAs) covers 24% (1 440 000 km(2)) of the total CCZ planning region and serves as example of swift and pre-emptive conservation planning across an unprecedented area in the deep sea. As pressure from resource extraction increases in the future, the scientific guiding principles outlined in this research can serve as a basis for collaborative international approaches to ocean management.

Prevalence of calcified carotid artery atheromas on panoramic images of individuals with primary hyperparathyroidism.

OBJECTIVES: Primary hyperparathyroidism (PHPT), affecting 1% of the population, is associated with increased cardiovascular morbidity and mortality. The presence of calcified carotid artery plaque (CCAP) on panoramic images is a validated risk indicator of future adverse cardiovascular events. We hypothesized that military veterans aged 50 years or older diagnosed with PHPT by increased parathyroid hormone and calcium levels would frequently have CCAP on their images. METHODS: We determined the prevalence rates of CCAP on the images of patients diagnosed with PHPT and evaluated their atherogenic risk profiles, including hypertension, dyslipidaemia, diabetes and obesity. Comparisons of atherogenic risk factors were made between subjects with and without observed CCAP on their panoramic images. RESULTS: Of the 60 patients (86.7% males and 13.3% females, mean age 73.2 ± 11.3 years) with PHPT, 40% had atheromas. There were no significant differences between CCAP+ and CCAP- groups in gender or race (p > 0.05). The atherogenic profile (age, body mass index, hypertension, diabetes, hyperlipidaemia) in the CCAP+ and CCAP- groups was not significantly different (p > 0.05). CONCLUSIONS: Calcified carotid artery atheromas are often seen on the panoramic images of patients with PHPT. Thus, dentists must be uniquely vigilant for these lesions when evaluating these studies.

Panoramic images of white and black post-menopausal females evidencing carotid calcifications are at high risk of comorbid osteopenia of the femoral neck.

OBJECTIVES: Femoral neck fractures in older females resulting from decreased bone mineral density (BMD; osteopenia) are associated with increased morbidity and mortality. Bone mineralization inhibition is probably controlled by proteins which also foster vascular calcification. Therefore, we evaluated the relationship between calcified carotid artery plaque (CCAP) on panoramic images and BMD on dual energy X-ray absorptiometry (DXA) bone scans. METHODS: Images and hospital records identified by dentists defined two study groups (20 white females and 24 black females) having CCAP and an incidentally obtained bone scan. Ethnically matched (age±7 years, body mass index ±3 units) control groups with panoramic images devoid of CCAP and accompanying DXA scan were likewise constituted. A physician determined the BMD on the DXA. RESULTS: Females with CCAP had significantly (p = 0.03) poorer BMD at the femoral neck than those without CCAP. Although mean femoral neck BMD was significantly lower (p = 0.009) for white than for black females, there was no significant interaction between race and CCAP (p = 0.80). CONCLUSION: We observed a significant inverse association between the CCAP on panoramic images and femoral neck BMD in post-menopausal white females.

Bilateral bifid mandibular condyles diagnosed with three-dimensional reconstruction.

Bifid mandibular condyles (BMCs) are rare anomalies. The overwhelming majority of prior reports described their predominantly unilateral occurrence diagnosed by panoramic radiography. We present an even rarer case of bilateral BMC initially identified by panoramic radiography and confirmed with colour-enhanced three-dimensional CT. These images substantiate the theory that the secondary condyles arise from the neck of the mandible (Lopez-Lopez et al. Bifid condyle: review of the literature of the last 10 years and report of two cases. Cianio 2010; 28: 136-140).

Processing, assembly and localization of a Bacillus anthracis spore protein.

All Bacillus spores are encased in macromolecular shells. One of these is a proteinacious shell called the coat that, in Bacillus subtilis, provides critical protective functions. The Bacillus anthracis spore is the infectious particle for the disease anthrax. Therefore, the coat is of particular interest because it may provide essential protective functions required for the appearance of anthrax. Here, we analyse a protein component of the spore outer layers that was previously designated BxpA. Our data indicate that a significant amount of BxpA is located below the spore coat and associated with the cortex. By SDS-PAGE, BxpA migrates as a 9 kDa species when extracted from Sterne strain spores, and as 11 and 14 kDa species from Ames strain spores, even though it has predicted masses of 27 and 29 kDa, respectively, in these two strains. We investigated the possibility that BxpA is subject to post-translational processing as previously suggested. In B. subtilis, a subset of coat proteins is proteolysed or cross-linked by the spore proteins YabG or Tgl, respectively. To investigate the possibility that similar processing occurs in B. anthracis, we generated mutations in the yabG or tgl genes in the Sterne and Ames strains and analysed the consequences for BxpA assembly by SDS-PAGE. We found that in a tgl mutant of B. anthracis, the apparent mass of BxpA increased. This is consistent with the possibility that Tgl directs the cross-linking of BxpA into a form that normally does not enter the gel. Unexpectedly, the apparent mass of BxpA also increased in a yabG mutant, suggesting a relatively complex role for proteolysis in spore protein maturation in B. anthracis. These data reveal a previously unobserved event in spore protein maturation in B. anthracis. We speculate that proteolysis and cross-linking are ubiquitous spore assembly mechanisms throughout the genus Bacillus.

Association of Bacillus anthracis capsule with lethal toxin during experimental infection.

Bacillus anthracis lethal toxin (LT) was characterized in plasma from infected African Green monkeys, rabbits, and guinea pigs. In all cases, during the terminal phase of infection only the protease-activated 63-kDa form of protective antigen (PA(63)) and the residual 20-kDa fragment (PA(20)) were detected in the plasma. No uncut PA with a molecular mass of 83 kDa was detected in plasma from toxemic animals during the terminal stage of infection. PA(63) was largely associated with lethal factor (LF), forming LT. Characterization of LT by Western blotting, capture enzyme-linked immunosorbent assay, and size exclusion chromatography revealed that the antiphagocytic poly-gamma-d-glutamic acid (gamma-DPGA) capsule released from B. anthracis bacilli was associated with LT in animal blood in variable amounts. While the nature of this in vivo association is not understood, we were able to determine that a portion of these LT/gamma-DPGA complexes retained LF protease activity. Our findings suggest that the in vivo LT complexes differ from in vitro-produced LT and that including gamma-DPGA when examining the effects of LT on specific immune cells in vitro may reveal novel and important roles for gamma-DPGA in anthrax pathogenesis.

Distribution, size frequency, and sex ratios of blacktip reef sharks Carcharhinus melanopterus at Palmyra Atoll: a predator-dominated ecosystem.

Blacktip reef sharks Carcharhinus melanopterus were the most abundant predator in the lagoons at Palmyra Atoll. They were evenly distributed throughout the lagoons, although there was some evidence of sexual segregation. Males reach sexual maturity between 940-1,020 mm L(T). Bird remains were found in some C. melanopterus stomachs. C. melanopterus at Palmyra appear to be smaller than those at other locations.