Intraspecific variation and directional casque asymmetry in adult southern cassowaries (Casuarius casuarius).

The cranial casques of modern cassowaries (Casuarius) have long intrigued researchers; however, in-depth studies regarding their morphological variation are scarce. Through visual inspection, it has been recognized that casque variability exists between conspecifics. Understanding casque variation has both evolutionary and ecological importance. Although hypothesized to be targeted by selection, intraspecific casque variation has not been quantified previously. Through a large sample of C. casuarius (n = 103), we compared casque shape (lateral and rostral views) between sexes and between individuals from non-overlapping geographical regions using two-dimensional (2D) geometric morphometrics. We found no statistically significant differences between the casque shape of females and males and few substantial shape differences between individuals from different geographic areas. Much of the intraspecific variation within C. casuarius is due to casque asymmetries (77.5% rightward deviating, 20.7% leftward deviating, and 1.8% non-deviating from the midline; n = 111), which explain the high variability of southern cassowary casque shape, particularly from the rostral aspect. Finally, we discuss how our non-significant findings implicate social selection theory, and we identify the benefits of quantifying such variation for further elucidating casque function(s) and the social biology of cassowaries.

Lung Computational Models and the Role of the Small Airways in Asthma.

Rationale: Asthma is characterized by disease within the small airways. Several studies have suggested that forced oscillation technique-derived resistance at 5 Hz (R5) - resistance at 20 Hz (R20) is a measure of small airway disease; however, there has been limited validation of this measurement to date.Objectives: To validate the use of forced oscillation R5 - R20 as a measure of small airway narrowing in asthma, and to investigate the role that small airway narrowing plays in asthma.Methods: Patient-based complete conducting airway models were generated from computed tomography scans to simulate the impact of different degrees of airway narrowing at different levels of the airway tree on forced oscillation R5 - R20 (n = 31). The computational models were coupled with regression models in an asthmatic cohort (n = 177) to simulate the impact of small airway narrowing on asthma control and quality of life. The computational models were used to predict the impact on small airway narrowing of type-2 targeting biologics using pooled data from two similarly design randomized, placebo-controlled biologic trials (n = 137).Measurements and Main Results: Simulations demonstrated that narrowing of the small airways had a greater impact on R5 - R20 than narrowing of the larger airways and was associated (above a threshold of approximately 40% narrowing) with marked deterioration in both asthma control and asthma quality of life, above the minimal clinical important difference. The observed treatment effect on R5 - R20 in the pooled trials equated to a predicted small airway narrowing reversal of approximately 40%.Conclusions: We have demonstrated, using computational modeling, that forced oscillation R5 - R20 is a direct measure of anatomical narrowing in the small airways and that small airway narrowing has a marked impact on both asthma control and quality of life and may be modified by biologics.

Dinosaur incubation periods directly determined from growth-line counts in embryonic teeth show reptilian-grade development.

Birds stand out from other egg-laying amniotes by producing relatively small numbers of large eggs with very short incubation periods (average 11-85 d). This aspect promotes high survivorship by limiting exposure to predation and environmental perturbation, allows for larger more fit young, and facilitates rapid attainment of adult size. Birds are living dinosaurs; their rapid development has been considered to reflect the primitive dinosaurian condition. Here, nonavian dinosaurian incubation periods in both small and large ornithischian taxa are empirically determined through growth-line counts in embryonic teeth. Our results show unexpectedly slow incubation (2.8 and 5.8 mo) like those of outgroup reptiles. Developmental and physiological constraints would have rendered tooth formation and incubation inherently slow in other dinosaur lineages and basal birds. The capacity to determine incubation periods in extinct egg-laying amniotes has implications for dinosaurian embryology, life history strategies, and survivorship across the Cretaceous-Paleogene mass extinction event.

Rate and risk factors for post-adenotonsillectomy complications in children under 24 months and 24 to 36 months old.

PURPOSE: The primary purpose of this study was to assess the overall rate of postoperative complications after adenotonsillectomy in children under 24 months old relative to children 24-36 months old. Our secondary goal focused on quantifying specific preoperative risk factors that predispose children to postoperative complications. METHODS: We retrospectively reviewed 248 patients who underwent adenotonsillectomy at our ENT office from 2006 to 2011. We stratified these patients into two groups: under 2 years old; and 2-3 years old. We identified 42 preoperative risk factors and 22 postoperative complications for each age group and conducted tests of statistical significance. RESULTS: We found that children under 24 months old had a statistically significant higher postoperative complication rate of 38% compared to 22.3% in children 2-3 years old (p = 0.0320, chi-squared test). For specific complications, younger children had a higher rate of respiratory distress within 24 h (p = 0.0355), endotracheal re-intubation (p = 0.0281), and retractions (p = 0.0281). The only identified risk factors aside from age demonstrating statistical significance were nasal steroid sprays used preoperatively in children under 24 months (p = 0.005) and concurrent tympanostomy tube placement in children 24-36 months (p = 0.026). CONCLUSION: Our data demonstrates that children under 2 years of age have an overall increased rate of postoperative complications after adenotonsillectomy when compared to children between 2 and 3 years old, with a significantly higher rates of early respiratory distress, endotracheal re-intubation, and retractions. This study is one of the largest that compares postoperative complication rates and risk factors after adenotonsillectomy in this age group.

Functional CT imaging for identification of the spatial determinants of small-airways disease in adults with asthma.

BACKGROUND: Asthma is a disease characterized by ventilation heterogeneity (VH). A number of studies have demonstrated that VH markers derived by using impulse oscillometry (IOS) or multiple-breath washout (MBW) are associated with key asthmatic patient-related outcome measures and airways hyperresponsiveness. However, the topographical mechanisms of VH in the lung remain poorly understood. OBJECTIVES: We hypothesized that specific regionalization of topographical small-airway disease would best account for IOS- and MBW-measured indices in patients. METHODS: We evaluated the results of paired expiratory/inspiratory computed tomography in a cohort of asthmatic (n = 41) and healthy (n = 11) volunteers to understand the determinants of clinical VH indices commonly reported by using IOS and MBW. Parametric response mapping (PRM) was used to calculate the functional small-airways disease marker PRMfSAD and Hounsfield unit (HU)-based density changes from total lung capacity to functional residual capacity (ΔHU); gradients of ΔHU in gravitationally perpendicular (parallel) inferior-superior (anterior-posterior) axes were quantified. RESULTS: The ΔHU gradient in the inferior-superior axis provided the highest level of discrimination of both acinar VH (measured by using phase 3 slope analysis of multiple-breath washout data) and resistance at 5 Hz minus resistance at 20 Hz measured by using impulse oscillometry (R5-R20) values. Patients with a high inferior-superior ΔHU gradient demonstrated evidence of reduced specific ventilation in the lower lobes of the lungs and high levels of PRMfSAD. A computational small-airway tree model confirmed that constriction of gravitationally dependent, lower-zone, small-airway branches would promote the largest increases in R5-R20 values. Ventilation gradients correlated with asthma control and quality of life but not with exacerbation frequency. CONCLUSIONS: Lower lobe-predominant small-airways disease is a major driver of clinically measured VH in adults with asthma.

Neural crest migration is driven by a few trailblazer cells with a unique molecular signature narrowly confined to the invasive front.

Neural crest (NC) cell migration is crucial to the formation of peripheral tissues during vertebrate development. However, how NC cells respond to different microenvironments to maintain persistence of direction and cohesion in multicellular streams remains unclear. To address this, we profiled eight subregions of a typical cranial NC cell migratory stream. Hierarchical clustering showed significant differences in the expression profiles of the lead three subregions compared with newly emerged cells. Multiplexed imaging of mRNA expression using fluorescent hybridization chain reaction (HCR) quantitatively confirmed the expression profiles of lead cells. Computational modeling predicted that a small fraction of lead cells that detect directional information is optimal for successful stream migration. Single-cell profiling then revealed a unique molecular signature that is consistent and stable over time in a subset of lead cells within the most advanced portion of the migratory front, which we term trailblazers. Model simulations that forced a lead cell behavior in the trailing subpopulation predicted cell bunching near the migratory domain entrance. Misexpression of the trailblazer molecular signature by perturbation of two upstream transcription factors agreed with the in silico prediction and showed alterations to NC cell migration distance and stream shape. These data are the first to characterize the molecular diversity within an NC cell migratory stream and offer insights into how molecular patterns are transduced into cell behaviors.

Local Government Capacity to Respond to Environmental Change: Insights from Towns in New York State.

Local governments attempting to respond to environmental change face an array of challenges. To better understand policy responses and factors influencing local government capacity to respond to environmental change, we studied three environmental issues affecting rural or peri-urban towns in different regions of New York State: climate change in the Adirondacks (n = 63 towns), loss of open space due to residential/commercial development in the Hudson Valley (n = 50), and natural gas development in the Southern Tier (n = 62). Our analysis focused on towns' progression through three key stages of the environmental policy process (issue awareness and salience, common goals and agenda setting, policy development and implementation) and the factors that affect this progression and overall capacity for environmental governance. We found that-when compared to towns addressing open space development and natural gas development-towns confronted with climate change were at a much earlier stage in the policy process and were generally less likely to display the essential resources, social support, and political legitimacy needed for an effective policy response. Social capital cultivated through collaboration and networking was strongly associated with towns' policy response across all regions and could help municipalities overcome omnipresent resource constraints. By comparing and contrasting municipal responses to each issue, this study highlights the processes and factors influencing local government capacity to address a range of environmental changes across diverse management contexts.

VEGF signals induce trailblazer cell identity that drives neural crest migration.

Embryonic neural crest cells travel in discrete streams to precise locations throughout the head and body. We previously showed that cranial neural crest cells respond chemotactically to vascular endothelial growth factor (VEGF) and that cells within the migratory front have distinct behaviors and gene expression. We proposed a cell-induced gradient model in which lead neural crest cells read out directional information from a chemoattractant profile and instruct trailers to follow. In this study, we show that migrating chick neural crest cells do not display distinct lead and trailer gene expression profiles in culture. However, exposure to VEGF in vitro results in the upregulation of a small subset of genes associated with an in vivo lead cell signature. Timed addition and removal of VEGF in culture reveals the changes in neural crest cell gene expression are rapid. A computational model incorporating an integrate-and-switch mechanism between cellular phenotypes predicts migration efficiency is influenced by the timescale of cell behavior switching. To test the model hypothesis that neural crest cellular phenotypes respond to changes in the VEGF chemoattractant profile, we presented ectopic sources of VEGF to the trailer neural crest cell subpopulation and show diverted cell trajectories and stream alterations consistent with model predictions. Gene profiling of trailer cells that diverted and encountered VEGF revealed upregulation of a subset of 'lead' genes. Injection of neuropilin1 (Np1)-Fc into the trailer subpopulation or electroporation of VEGF morpholino to reduce VEGF signaling failed to alter trailer neural crest cell trajectories, suggesting trailers do not require VEGF to maintain coordinated migration. These results indicate that VEGF is one of the signals that establishes lead cell identity and its chemoattractant profile is critical to neural crest cell migration.

Prospective comparative study of pulsed-electron avalanche knife (PEAK) and bipolar radiofrequency ablation (coblation) pediatric tonsillectomy and adenoidectomy.

PURPOSE: To compare post-operative pain severity, analgesic intake, and complications in children undergoing tonsillectomy and adenoidectomy with bipolar radiofrequency ablation (Coblation) vs. pulsed-electron avalanche knife (PEAK) technology. MATERIALS AND METHODS: This was a prospective, non-randomized, non-blinded comparative cohort study in a private practice setting with three fellowship-trained pediatric otolaryngologists. Patients aged 3 to 12years undergoing tonsillectomy and adenoidectomy were assigned to surgery with either bipolar radiofrequency ablation or pulsed electron avalanche knife instrumentation. Daily telephone contact for the first 14 post-operative days obtained the following data: validated proxy pain scale scores, number of post-operative analgesic medication doses consumed, and occurrence and severity of post-operative hemorrhage. RESULTS: One-hundred adenotonsillectomy subjects were enrolled (50 bipolar radiofrequency ablation, 50 pulsed-electron avalanche knife). There were no clinically relevant differences in post-operative pain scores between the two surgical groups on all post-operative days. Total doses of non-narcotic and narcotic analgesics were similar between the groups, with the exception of less acetaminophen doses being consumed in pulsed-electron avalanche knife patients on post-operative days 9, 10, and 12. Post-operative hemorrhage episodes resulting in re-operation and/or hospitalization were equivalent between the two groups. However, bipolar radiofrequency ablation patients were 2.33 times more likely to experience minor bleeding events at home (that did not require medical intervention). CONCLUSION: Pulsed-electron avalanche knife surgery was found to be an adequate technique for pediatric adenotonsillectomy, with similar amounts of post-operative pain and clinically relevant hemorrhage when compared to bipolar radiofrequency ablation.

Multi-cellular rosettes in the mouse visceral endoderm facilitate the ordered migration of anterior visceral endoderm cells.

The visceral endoderm (VE) is a simple epithelium that forms the outer layer of the egg-cylinder stage mouse embryo. The anterior visceral endoderm (AVE), a specialised subset of VE cells, is responsible for specifying anterior pattern. AVE cells show a stereotypic migratory behaviour within the VE, which is responsible for correctly orientating the anterior-posterior axis. The epithelial integrity of the VE is maintained during the course of AVE migration, which takes place by intercalation of AVE and other VE cells. Though a continuous epithelial sheet, the VE is characterised by two regions of dramatically different behaviour, one showing robust cell movement and intercalation (in which the AVE migrates) and one that is static, with relatively little cell movement and mixing. Little is known about the cellular rearrangements that accommodate and influence the sustained directional movement of subsets of cells (such as the AVE) within epithelia like the VE. This study uses an interdisciplinary approach to further our understanding of cell movement in epithelia. Using both wild-type embryos as well as mutants in which AVE migration is abnormal or arrested, we show that AVE migration is specifically linked to changes in cell packing in the VE and an increase in multi-cellular rosette arrangements (five or more cells meeting at a point). To probe the role of rosettes during AVE migration, we develop a mathematical model of cell movement in the VE. To do this, we use a vertex-based model, implemented on an ellipsoidal surface to represent a realistic geometry for the mouse egg-cylinder. The potential for rosette formation is included, along with various junctional rearrangements. Simulations suggest that while rosettes are not essential for AVE migration, they are crucial for the orderliness of this migration observed in embryos. Our simulations are similar to results from transgenic embryos in which Planar Cell Polarity (PCP) signalling is disrupted. Such embryos have significantly reduced rosette numbers, altered epithelial packing, and show abnormalities in AVE migration. Our results show that the formation of multi-cellular rosettes in the mouse VE is dependent on normal PCP signalling. Taken together, our model and experimental observations suggest that rosettes in the VE epithelium do not form passively in response to AVE migration. Instead, they are a PCP-dependent arrangement of cells that acts to buffer the disequilibrium in cell packing generated in the VE by AVE migration, enabling AVE cells to migrate in an orderly manner.

Evidence of viral dissemination and seasonality in a Mediterranean river catchment: Implications for water pollution management.

Conventional wastewater treatment does not completely remove and/or inactive viruses; consequently, viruses excreted by the population can be detected in the environment. This study was undertaken to investigate the distribution and seasonality of human viruses and faecal indicator bacteria (FIB) in a river catchment located in a typical Mediterranean climate region and to discuss future trends in relation to climate change. Sample matrices included river water, untreated and treated wastewater from a wastewater treatment plant within the catchment area, and seawater from potentially impacted bathing water. Five viruses were analysed in the study. Human adenovirus (HAdV) and JC polyomavirus (JCPyV) were analysed as indicators of human faecal contamination of human pathogens; both were reported in urban wastewater (mean values of 10(6) and 10(5) GC/L, respectively), river water (10(3) and 10(2) GC/L) and seawater (10(2) and 10(1) GC/L). Human Merkel Cell polyomavirus (MCPyV), which is associated with Merkel Cell carcinoma, was detected in 75% of the raw wastewater samples (31/37) and quantified by a newly developed quantitative polymerase chain reaction (qPCR) assay with mean concentrations of 10(4) GC/L. This virus is related to skin cancer in susceptible individuals and was found in 29% and 18% of river water and seawater samples, respectively. Seasonality was only observed for norovirus genogroup II (NoV GGII), which was more abundant in cold months with levels up to 10(4) GC/L in river water. Human hepatitis E virus (HEV) was detected in 13.5% of the wastewater samples when analysed by nested PCR (nPCR). Secondary biological treatment (i.e., activated sludge) and tertiary sewage disinfection including chlorination, flocculation and UV radiation removed between 2.22 and 4.52 log10 of the viral concentrations. Climate projections for the Mediterranean climate areas and the selected river catchment estimate general warming and changes in precipitation distribution. Persistent decreases in precipitation during summer can lead to a higher presence of human viruses because river and sea water present the highest viral concentrations during warmer months. In a global context, wastewater management will be the key to preventing environmental dispersion of human faecal pathogens in future climate change scenarios.

Incorporating chemical signalling factors into cell-based models of growing epithelial tissues.

In this paper we present a comprehensive computational framework within which the effects of chemical signalling factors on growing epithelial tissues can be studied. The method incorporates a vertex-based cell model, in conjunction with a solver for the governing chemical equations. The vertex model provides a natural mesh for the finite element method (FEM), with node movements determined by force laws. The arbitrary Lagrangian-Eulerian formulation is adopted to account for domain movement between iterations. The effects of cell proliferation and junctional rearrangements on the mesh are also examined. By implementing refinements of the mesh we show that the finite element (FE) approximation converges towards an accurate numerical solution. The potential utility of the system is demonstrated in the context of Decapentaplegic (Dpp), a morphogen which plays a crucial role in development of the Drosophila imaginal wing disc. Despite the presence of a Dpp gradient, growth is uniform across the wing disc. We make the growth rate of cells dependent on Dpp concentration and show that the number of proliferation events increases in regions of high concentration. This allows hypotheses regarding mechanisms of growth control to be rigorously tested. The method we describe may be adapted to a range of potential application areas, and to other cell-based models with designated node movements, to accurately probe the role of morphogens in epithelial tissues.

Midfoot arthrodesis following multi-joint stabilization with a novel hybrid plating system.

BACKGROUND: Several methods for fixation have been described for midfoot arthrodesis. Multi-joint arthrodesis at this level can be challenging because of bone loss and deformity, making it difficult to obtain a stable construct. We present the results of a novel hybrid plating system that incorporates locked and non-locked compression screws for multi-joint arthrodesis of the midfoot. METHOD: A retrospective multicenter review of patients undergoing multi-joint arthrodesis with hybrid plating of the midfoot was performed to evaluate the time to radiographic arthrodesis. Hybrid plating was defined as a construct that incorporates locked and non-locked compression screws. Neuropathy was the only exclusion criteria. Radiographic arthrodesis was defined as bridging bone on one of the three standard foot radiographs in the absence of a joint gap on the other views, or by 50% or greater bridging bone on computed tomography. Etiology of the arthritis, presurgical comorbidities, body mass index, functional level and postoperative complications were evaluated. RESULTS: Seventy-two patients were evaluated, and arthrodesis was obtained in 67 patients at 6 weeks in 27 patients, 9 weeks in 26, 12 weeks in 11, and at 16 weeks in three. In five patients at least one of the joints were not fused at 16 weeks and were considered a nonunion. Complications were present in 12 patients (17%). CONCLUSIONS: The healing rate and time to arthrodesis compared favorably to similar published studies. Based on these results, hybrid plating was a reliable and consistent alternative for fixation in midfoot arthrodesis, especially in multi-joint disease.

Validation of the traditional Chinese version of the Sinus and Nasal Quality of Life Survey (SN-5) for children.

BACKGROUND: Persistent sinonasal symptoms are common in children with chronic rhinosinusitis. The Sinus and Nasal Quality of Life (QoL) Survey (SN-5) was the first validated questionnaire measuring sinonasal-related QoL in populations aged 2-12 years. No norm has been established for Chinese-speaking countries. We translated the SN-5 into traditional Chinese and evaluated validity and reliability. METHODS: From December 2016 to December 2017, healthy volunteers and children with persistent sinonasal symptoms were enrolled. Guardians of the participants completed the SN-5, a visual analog scale (VAS) of nasal symptoms, and the Obstructive Sleep Apnea-18 (OSA-18); the responses were used to assess internal consistency, discriminant validity, and treatment responsiveness. A nontreatment group was administered the SN-5 1 week later to assess test-retest reliability. RESULTS: We recruited 31 healthy volunteers and 85 children with rhinosinusitis, 50 and 35 in the treatment and nontreatment groups, respectively. The SN-5 demonstrated good internal consistency (Cronbach's α = 0.86) and test-retest reliability (0.74, p < 0.01). It exhibited good discriminant validity between the healthy and rhinosinusitis groups (p < 0.001). The SN-5 scores were correlated with the VAS scores (0.63, p < 0.001). The effect size of the SN-5 scores was 0.51. The total SN-5 and OSA-18 scores changed significantly after 4-week treatment (p < 0.05) and demonstrated good responsiveness. The SN-5 and OSA-18 scores were significantly and positively correlated (r2 = 0.53, p < 0.001). CONCLUSION: Our traditional Chinese version of the SN-5 is reliable and valid for measuring sinonasal-related QoL in children in Chinese-speaking countries. TRIAL REGISTRATION NUMBER: NCT04836403.

Quantitative microbial risk assessment of cryptosporidiosis and giardiasis from very small private water supplies.

This article reports a quantitative microbial risk assessment of the risk of Giardia and Cryptosporidium in very small private water supplies. Both pathogens have been implicated in causing outbreaks of waterborne disease associated with such supplies, though the risk of endemic disease is not known. For exposure assessments, we used existing data to derive regression equations describing the relationships between the concentration of these pathogens and Escherichia coli in private water supplies. Pathogen concentrations were then estimated using national surveillance data of E. coli in private water supplies in England and France. The estimated risk of infection was very high with the median annual risk being of the order of 25-28% for Cryptosporidium and 0.4% to 0.7% for Giardia, though, in the poorer quality supplies the risk could be much higher. These risks are substantially greater than for public water supplies and well above the risk considered tolerable. The observation that observed infection rates are generally much lower may indicate increased immunity in people regularly consuming water from private supplies. However, this increased immunity is presumed to derive from increased disease risk in young children, the group most at risk from severe disease.

Perfusion pressures and distal oxygenation in individuals with diabetes undergoing chronic hemodialysis.

BACKGROUND: The number of diabetic patients worldwide was estimated to be approximately 285 million in 2010. Approximately 5% of all diabetic patients have foot ulcers, often preceded by neuropathy and delayed healing resulting from peripheral vascular disease which leads to increased risk of infection. Additionally, there is a concern that blood flow to the feet may be reduced in patients with diabetes, which may be further compounded by changes in lower extremity perfusion pressure during hemodialysis. Current laser Doppler technology provides the opportunity to identify changes in vascularityin a non-invasive fashion. MATERIALS AND METHODS: A prospective, parallel-arm, comparison, pilot study was conducted. A total of 15 patients were enrolled, ten of whom had a documented history of diabetes. All patients required hemodialysis. Peripheral perfusion and oxygenation measurements were obtained before, midway and at the conclusion of three separate dialysis sessions within a 3-week interval for each subject. RESULTS: Preliminary results indicate a significant reduction in toe pressure during and after hemodialysis in the diabetic patient group compared to the non-diabetic group. Significant differences were not found in skin perfusion measurements or in the oxygenation measurements at any time in diabetic and nondiabetic patients undergoing hemodialysis. CONCLUSION: Preliminary results suggest hemodialysis may significantly affect pressure of the lower extremities in diabetic patients. Trends from these data indicate the need to further investigate the effect of hemodialysis on techniques used to heal wounds and ulcers in patients with diabetes.

Detection of Cryptosporidium species and sources of contamination with Cryptosporidium hominis during a waterborne outbreak in north west Wales.

As part of investigations into the cause of a waterborne outbreak of Cryptosporidium hominis infection linked to a mains water supply, surface waters and wastewater treatment plants were tested for Cryptosporidium spp. Oocyst counts in base flow surface water samples ranged from nil to 29 per 10 l. Oocyst counts in effluent from a community wastewater treatment plant were up to 63 fold higher and breakout from one septic tank five logs higher. There were no peak (storm) flow events during the investigation. C. hominis, four named genotypes (cervine, muskrat II, rat, W19) and six new small subunit ribosomal RNA gene sequences were identified. Four of the new sequences were closely related to Cryptosporidium muskrat genotype I, one was closely related to the fox genotype and one to Cryptosporidium canis. C. hominis was found extensively in the catchment, but only at sites contaminated by wastewater, and in the treated water supply to the affected area. All were gp60 subtype IbA10G2, the outbreak subtype. Multiple routes of contamination of the reservoir were identified, resulting in persistent detection of low numbers of oocysts in the final water. This work demonstrates the utility of genotyping Cryptosporidium isolates in environmental samples during outbreak investigations.

Tropical aquarium aquatic dermatoses: bristle worm envenomation.

A 55-year-old high school science teacher with diabetes presented with severe pain and swelling of his left hand. He reported receiving a "shock" 2 days earlier while cleaning out his classroom's aquarium with a bare left hand. Thinking it was a "short" in the electrical connections to the aquarium's pump, he disconnected the electrical cord and continued to clean behind the pump mechanism. After a few more such shocks he put on a glove and retrieved 10 foot-long worms. Antibiotics were started. It took more than 2 weeks for the hand to return to its normal size. On presentation to our office, the patient's left hand was moderately swollen, with blistering and purpura seen on his distal fingers. He reported pain, itching, and numbness in the hand, which was getting worse. No systemic symptoms were reported. The patient was a non-insulin-dependent diabetic who was also taking warfarin for a carotid vascular problem. He brought to our office a bucket with coiled aquatic worms at the bottom (Figure 1). When extended, they measured about 1 foot and their morphology could be better seen (Figure 2). No spicules could be seen in the patient's hand on magnification, but taping was performed to remove any possible residual spicules. The patient was given oral antibiotics, a Medrol dose pack, oral antihistamines, and topical corticosteroids. Within 1 day of starting treatment his symptoms and hand swelling began to abate, by 1 week his hand skin peeled, and by 2 weeks the swelling and skin appearance was almost back to normal. Bacterial cultures of the hand's wounds showed no growth.