Widespread amphibian Perkinsea infections associated with Ranidae hosts, cooler months and Ranavirus co-infection.

Amphibians suffer from large-scale population declines globally, and emerging infectious diseases contribute heavily to these declines. Amphibian Perkinsea (Pr) is a worldwide anuran pathogen associated with mass mortality events, yet little is known about its epidemiological patterns, especially in comparison to the body of literature on amphibian chytridiomycosis and ranavirosis. Here, we establish Pr infection patterns in natural anuran populations and identify important covariates including climate, host attributes and co-infection with Ranavirus (Rv). We used quantitative (q)PCR to determine the presence and intensity of Pr and Rv across 1234 individuals sampled throughout central Florida in 2017-2019. We then implemented random forest ensemble learning models to predict infection with both pathogens based on physiological and environmental characteristics. Perkinsea infected 32% of all sampled anurans, and Pr prevalence was significantly elevated in Ranidae frogs, cooler months, metamorphosed individuals and frogs co-infected with Rv, while Pr intensity was significantly higher in ranid frogs and individuals collected dead. Ranavirus prevalence was 17% overall and was significantly higher in Ranidae frogs, metamorphosed individuals, locations with higher average temperatures, and individuals co-infected with Pr. Perkinsea prevalence was significantly higher than Rv prevalence across months, regions, life stages and species. Among locations, Pr prevalence was negatively associated with crayfish prevalence and positively associated with relative abundance of microhylids, but Rv prevalence did not associate with any tested co-variates. Co-infections were significantly more common than single infections for both pathogens, and we propose that Pr infections may propel Rv infections because seasonal Rv infection peaks followed Pr infection peaks and random forest models found Pr intensity was a leading factor explaining Rv infections. Our study elucidates epidemiological patterns of Pr in Florida and suggests that Pr may be under-recognized as a cause of anuran declines, especially in the context of pathogen co-infection.

Multiple propane gas burn rates procedure to determine accuracy and linearity of indirect calorimetry systems: an experimental assessment of a method.

Objective: Indirect calorimetry (IC) systems measure the fractions of expired carbon dioxide (FeCO2), and oxygen (FeO2) recorded at the mouth to estimate whole-body energy production. The fundamental principle of IC relates to the catabolism of high-energy substrates such as carbohydrates and lipids to meet the body's energy needs through the oxidative process, which are reflected in the measured oxygen uptake rates (V̇O2) and carbon dioxide production rates (V̇CO2). Accordingly, it is important to know the accuracy and validity of V̇O2and V̇CO2 measurements when estimating energy production and substrate partitioning for research and clinical purposes. Although several techniques are readily available to assess the accuracy of IC systems at a single point for V̇CO2 and V̇O2, the validity of such procedures is limited when used in testing protocols that incorporate a wide range of energy production (e.g., basal metabolic rate and maximal exercise testing). Accordingly, we built an apparatus that allowed us to manipulate propane burn rates in such a way as to assess the linearity of IC systems. This technical report aimed to assess the accuracy and linearity of three IC systems using our in-house built validation procedure. Approach: A series of trials at different propane burn rates (PBR) (i.e., 200, 300, 400, 500, and 600 mL min-1) were run on three IC systems: Sable, Moxus, and Oxycon Pro. The experimental values for V̇O2 and V̇CO2 measured on the three IC systems were compared to theoretical stoichiometry values. Results: A linear relationship was observed between increasing PBR and measured values for V̇O2and V̇CO2 (99.6%, 99.2%, 94.8% for the Sable, Moxus, and Jaeger IC systems, respectively). In terms of system error, the Jaeger system had significantly (p < 0.001) greater V̇O2(mean difference (M) = -0.057, standard error (SE) = 0.004), and V̇CO2(M = -0.048, SE = 0.002) error compared to either the Sable (V̇O2, M = 0.044, SE = 0.004; V̇CO2, M = 0.024, SE = 0.002) or the Moxus (V̇O2, M = 0.046, SE = 0.004; V̇CO2, M = 0.025, SE = 0.002) IC systems. There were no significant differences between the Sable or Moxus IC systems. Conclusion: The multiple PBR approach permitted the assessment of linearity of IC systems in addition to determining the accuracy of fractions of expired gases.

Increasing use of an endotracheal intubation safety checklist in the emergency department.

Endotracheal intubation (ETI) is a high-risk procedure often performed in the emergency department (ED) in critically unwell patients. The fourth National Audit Project by The Royal College of Anaesthetists found the risk of adverse events is much higher when performing the intervention in this setting compared with a theatre suite, and therefore use of a safety checklist is recommended. This quality improvement project was set in a large teaching hospital in the North West of the UK, where anaesthesia and intensive care clinicians are responsible for performing this procedure. A retrospective baseline audit indicated checklist use was 16.7% of applicable cases. The project aim was to increase the incidence of checklist use in the ED to 90% within a 6-month period. The model for improvement was used as a methodological approach to the problem along with other quality improvement tools, including a driver diagram to generate change ideas. The interventions were targeted at three broad areas: awareness of the checklist and expectation of use, building a favourable view of the benefits of the checklist and increasing the likelihood it would be remembered to use the checklist in the correct moment. After implementation checklist use increased to 84%. In addition, run chart analysis indicated a pattern of nonrandom variation in the form of a shift. This coincided with the period shortly after the beginning of the interventions. The changes were viewed favourably by junior and senior anaesthetists, as well as operating department practitioners and ED staff. Limitations of the project were that some suitable cases were likely missed due to the method of capture and lack of anonymous qualitative feedback on the changes made. Overall, however, it was shown the combination of low-cost interventions made was effective in increasing checklist use when performing emergency ETI in the ED.

The impact of perioperative inotropes on the incidence of pancreatic leak following pancreaticoduodenectomy.

BACKGROUNDS/AIMS: Pancreatic leak and fistula formation following pancreatic resection is a dreaded complication associated with significant morbidity and mortality. The perioperative use of inotropes has been implicated in anastomotic dehiscence in other types of gastrointestinal surgery but their impact in pancreatic surgery remains unclear and a potentially modifiable risk factor for pancreatic leak. This study aims to assess the impact of perioperative inotrope infusion on the incidence of pancreatic leak following pancreaticoduodenectomy. METHODS: Retrospective data analysis of all patients undergoing pancreaticoduodenectomy at a tertiary HPB institute. Multivariate analysis and regression models assessed the impact of inotrope use against other known risk factors such as pancreatic duct size and gland texture. Pancreatic fistulae were graded as per ISGPF as Grade A (biochemical leak), Grade B and Grade C fistula. RESULTS: One-hundred and twenty-three (123) patients were included. A total of 52 patients (42%) developed a leak (29 grade A, 15 grade B, and 8 Grade C). In the fistula group, 28 patients (55%) received perioperative inotropes compared to 26 (35%) in the no fistula group. On univariate analysis, patients receiving inotropes (p=0.04) and patients with a soft pancreatic texture (p=0.003) had a statistically higher incidence of developing a pancreatic fistula of any grade. On multivariate analysis, only inotrope use was associated with an increased risk of developing a pancreatic fistula of any grade (OR 2.46, p=0.026), independent of pancreatic texture and pancreatic duct size. CONCLUSIONS: Perioperative inotrope use is associated with an increase incidence of pancreatic leak following pancreaticoduodenectomy and should therefore be used judiciously.

Pathogen Dynamics in an Invasive Frog Compared to Native Species.

Emerging infectious diseases threaten the survival of wildlife populations and species around the world. In particular, amphibians are experiencing population declines and species extinctions primarily in response to two pathogens, the fungus Batrachochytrium dendrobatidis (Bd) and the iridovirus Ranavirus (Rv). Here, we use field surveys and quantitative (q)PCR to compare infection intensity and prevalence of Bd and Rv across species and seasons on Jekyll Island, a barrier island off the coast of Georgia, USA. We collected oral and skin swabs for 1 year from four anuran species and three families, including two native hylids (Hyla cinerea and Hyla squirella), a native ranid (Rana sphenocephala), and the invasive rain frog Eleutherodactylus planirostris. Bd infection dynamics did not vary significantly over sampling months, but Rv prevalence and intensity were significantly higher in fall 2014 compared to spring 2015. Additionally, Rv prevalence and intensity were significantly higher in E. planirostris than in the other three species. Our study highlights the potential role of invasive amphibians as drivers of disease dynamics and demonstrates the importance of pathogen surveillance across multiple time periods and species to accurately capture the infectious disease landscape.

Novel quantitative PCR assay specific for the emerging Perkinsea amphibian pathogen reveals seasonal infection dynamics.

Amphibians are suffering from large-scale population declines worldwide, and infectious diseases are a central driving force. Most pathogen-mediated declines are attributed to 2 pathogens, the fungus Batrachochytrium dendrobatidis and iridoviruses in the genus Ranavirus. However, another emerging pathogen within Perkinsea is associated with mass mortality events in anurans throughout the southeastern USA. Molecular resources for detecting amphibian Perkinsea have been limited to general protistan primers that amplify a range of organisms, not all of which are disease agents. Moreover, the only quantitative method available involves histopathology, which is labor intensive, requires destructive sampling, and lacks sensitivity. Here, we developed a novel quantitative (q)PCR assay that is sensitive and specific for amphibian Perkinsea, providing a resource for rapid and reliable pathogen diagnosis. We used histopathology to confirm that qPCR burdens track the severity of Perkinsea infections across multiple anuran tissues. We also sampled 3 natural amphibian communities in Florida, USA, to assess the prevalence and intensity of amphibian Perkinsea infections across species, seasons, tissues, and life stages. Anurans from 2 of 3 sampling locations were infected, totaling 25.1% of all individuals. Infection prevalence varied significantly among locations, seasons, species, and life stages. Infection intensity was significantly higher in larval tissues than adult tissues, and was significantly different across locations, seasons, and species. Understanding relationships between amphibian Perkinsea infection, other pathogens, and biotic and abiotic cofactors will allow us to assess what drives population declines, improving our ability to develop conservation strategies for susceptible species to reduce global amphibian biodiversity loss.

Use of prototype two-channel endoscope with elevator enables larger lift-and-snare endoscopic mucosal resection in a porcine model.

BACKGROUND: Flat and depressed lesions are becoming increasingly recognized in the esophagus, stomach, and colon. Various techniques have been described for endoscopic mucosal resection (EMR) of these lesions. AIMS: To evaluate the efficacy of lift-grasp-cut EMR using a prototype dual-channel forward-viewing endoscope with an instrument elevator in one accessory channel (dual-channel elevator scope) as compared to standard dual-channel endoscopes. METHODS: EMR was performed using a lift-grasp-cut technique on normal flat rectosigmoid or gastric mucosa in live porcine models after submucosal injection of 4 mL of saline using a dual-channel elevator scope or a standard dual-channel endoscope. With the dual-channel elevator scope, the elevator was used to attain further lifting of the mucosa. The primary endpoint was size of the EMR specimen and the secondary endpoint was number of complications. RESULTS: Twelve experiments were performed (six gastric and six colonic). Mean specimen diameter was 2.27 cm with the dual-channel elevator scope and 1.34 cm with the dual-channel endoscope (P = 0.018). Two colonic perforations occurred with the dual-channel endoscope, vs no complications with the dual-channel elevator scope. CONCLUSIONS: The increased lift of the mucosal epithelium, through use of the dual-channel elevator scope, allows for larger EMR when using a lift-grasp-cut technique. Noting the thin nature of the porcine colonic wall, use of the elevator may also make this technique safer.

Immediate unprepared hydroflush colonoscopy for severe lower GI bleeding: a feasibility study.

BACKGROUND: Urgent colonoscopy is not always the preferred initial intervention in severe lower GI bleeding because of the need for a large volume of oral bowel preparation, the time required for administering the preparation, and concern regarding adequate visualization. OBJECTIVE: To evaluate the feasibility, safety, and outcomes of immediate unprepared hydroflush colonoscopy for severe lower GI bleeding. DESIGN: Prospective feasibility study of immediate colonoscopy after tap-water enema without oral bowel preparation, aided by water-jet pumps and mechanical suction devices in patients admitted to the intensive care unit with a primary diagnosis of severe lower GI bleeding. SETTING: Tertiary referral center. MAIN OUTCOME MEASUREMENTS: Primary outcome measurement was the percentage of colonoscopies in which the preparation permitted satisfactory evaluation of the entire length of the colon suspected to contain the source of bleeding. Secondary outcome measurements were visualization of a definite source of bleeding, length of hospital and intensive care unit (ICU) stays, rebleeding rates, and transfusion requirements. RESULTS: Thirteen procedures were performed in 12 patients. Complete colonoscopy to the cecum was performed in 9 of 13 patients (69.2%). However, endoscopic visualization was thought to be adequate for definitive or presumptive identification of the source of bleeding in all procedures, with no colonoscopy repeated because of inadequate preparation. A definite source of bleeding was identified in 5 of 13 procedures (38.5%). The median length of ICU stay was 1.5 days; of hospital stay, 4.3 days. Recurrent bleeding during the same hospitalization, requiring repeated endoscopy, surgery, or angiotherapy, was seen in 3 of 12 patients (25%). LIMITATIONS: Uncontrolled feasibility study of selected patients. CONCLUSION: Immediate unprepared hydroflush colonoscopy in patients with severe lower GI bleeding is feasible with the hydroflush technique.

Characterization of the pancreas in vivo using EUS spectrum analysis with electronic array echoendoscopes.

BACKGROUND: Spectral analysis of the radiofrequency (RF) signals that underlie grayscale EUS images has been used to provide quantitative, objective information about tissue histology. OBJECTIVE: Our purpose was to validate RF spectral analysis as a method to distinguish between chronic pancreatitis (CP) and pancreatic cancer (PC). DESIGN AND SETTING: A prospective study of eligible patients was conducted to analyze the RF data obtained by using electronic array echoendoscopes. PATIENTS: Pancreatic images were obtained by using electronic array echoendoscopes from 41 patients in a prospective study, including 15 patients with PC, 15 with CP, and 11 with a normal pancreas. MAIN OUTCOME MEASUREMENTS: Midband fit, slope, intercept, correlation coefficient, and root mean square deviation from a linear regression of the calibrated power spectra were determined and compared among the groups. RESULTS: Statistical analysis showed that significant differences were observable between groups for mean midband fit, intercept, and root mean square deviation (t test, P < .05). Discriminant analysis of these parameters was then performed to classify the data. For CP (n = 15) versus PC (n = 15), the same parameters provided 83% accuracy and an area under the curve of 0.83. LIMITATIONS: Moderate sample size and spatial averaging inherent in the technique. CONCLUSIONS: This study shows that mean spectral parameters of the backscattered signals obtained by using electronic array echoendoscopes can provide a noninvasive method to quantitatively discriminate between CP and PC.

A randomized trial of rectal indomethacin to prevent post-ERCP pancreatitis.

BACKGROUND: Preliminary research suggests that rectally administered nonsteroidal antiinflammatory drugs may reduce the incidence of pancreatitis after endoscopic retrograde cholangiopancreatography (ERCP). METHODS: In this multicenter, randomized, placebo-controlled, double-blind clinical trial, we assigned patients at elevated risk for post-ERCP pancreatitis to receive a single dose of rectal indomethacin or placebo immediately after ERCP. Patients were determined to be at high risk on the basis of validated patient- and procedure-related risk factors. The primary outcome was post-ERCP pancreatitis, which was defined as new upper abdominal pain, an elevation in pancreatic enzymes to at least three times the upper limit of the normal range 24 hours after the procedure, and hospitalization for at least 2 nights. RESULTS: A total of 602 patients were enrolled and completed follow-up. The majority of patients (82%) had a clinical suspicion of sphincter of Oddi dysfunction. Post-ERCP pancreatitis developed in 27 of 295 patients (9.2%) in the indomethacin group and in 52 of 307 patients (16.9%) in the placebo group (P=0.005). Moderate-to-severe pancreatitis developed in 13 patients (4.4%) in the indomethacin group and in 27 patients (8.8%) in the placebo group (P=0.03). CONCLUSIONS: Among patients at high risk for post-ERCP pancreatitis, rectal indomethacin significantly reduced the incidence of the condition. (Funded by the National Institutes of Health; ClinicalTrials.gov number, NCT00820612.).

Endoscopically guided spectral-domain OCT with double-balloon catheters.

Fourier-domain optical coherence tomography (OCT) and balloon-based catheters have furthered the potential of OCT as a real-time surveillance tool for Barrett's esophagus (BE). However, a balloon catheter, which expands the esophagus and centers the catheter, applies direct pressure on the esophagus. This may affect the tissue appearance and the ability to detect dysplasia in BE. To study this effect, we propose a double-balloon catheter to allow imaging with and without balloon-tissue contact. A system design based on a spectral-domain OCT platform is reported and validated by acquisition of high quality, volumetric images of swine esophagus in vivo.

The children's Empathy Quotient and Systemizing Quotient: sex differences in typical development and in autism spectrum conditions.

Children's versions of the Empathy Quotient (EQ-C) and Systemizing Quotient (SQ-C) were developed and administered to n = 1,256 parents of typically developing children, aged 4-11 years. Both measures showed good test-retest reliability and high internal consistency. As predicted, girls scored significantly higher on the EQ-C, and boys scored significantly higher on the SQ-C. A further sample of n = 265 children with Autism Spectrum Conditions (ASC) scored significantly lower on the EQ-C, and significantly higher on the SQ-C, compared to typical boys. Empathy and systemizing in children show similar patterns of sex differences to those observed in adults. Children with ASC tend towards a 'hyper-masculinized' profile, irrespective of sex.