Airborne environmental DNA metabarcoding detects more diversity, with less sampling effort, than a traditional plant community survey.

BACKGROUND: Airborne environmental DNA (eDNA) research is an emerging field that focuses on the detection of species from their genetic remnants in the air. The majority of studies into airborne eDNA of plants has until now either focused on single species detection, specifically only pollen, or human health impacts, with no previous studies surveying an entire plant community through metabarcoding. We therefore conducted an airborne eDNA metabarcoding survey and compared the results to a traditional plant community survey. RESULTS: Over the course of a year, we conducted two traditional transect-based visual plant surveys alongside an airborne eDNA sampling campaign on a short-grass rangeland. We found that airborne eDNA detected more species than the traditional surveying method, although the types of species detected varied based on the method used. Airborne eDNA detected more grasses and forbs with less showy flowers, while the traditional method detected fewer grasses but also detected rarer forbs with large showy flowers. Additionally, we found the airborne eDNA metabarcoding survey required less sampling effort in terms of the time needed to conduct a survey and was able to detect more invasive species than the traditional method. CONCLUSIONS: Overall, we have demonstrated that airborne eDNA can act as a sensitive and efficient plant community surveying method. Airborne eDNA surveillance has the potential to revolutionize the way plant communities are monitored in general, track changes in plant communities due to climate change and disturbances, and assist with the monitoring of invasive and endangered species.

The detection of a non-anemophilous plant species using airborne eDNA.

Genetic analysis of airborne plant material has historically focused (generally implicitly rather than as a stated goal) on pollen from anemophilous (wind-pollinated) species, such as in multiple studies examining the relationship of allergens to human health. Inspired by the recent influx of literature applying environmental DNA (eDNA) approaches to targeted-species and whole-ecosystem study, we conducted a proof-of-concept experiment to determine whether airborne samples reliably detect genetic material from non-anemophilous species that may not be releasing large plumes of pollen. We collected airborne eDNA using Big Spring Number Eight dust traps and quantified the amount of eDNA present for a flowering wind-pollinated genus (Bouteloua) and insect-pollinated honey mesquite (Prosopis glandulosa) that was not flowering at the time of the study. We were able to detect airborne eDNA from both species. Since honey mesquite is insect-pollinated and was not flowering during the time of this study, our results confirm that airborne eDNA consists of and can detect species through more than just pollen. Additionally, we were able to detect temporal patterns reflecting Bouteloua reproductive ecology and suggest that airborne honey mesquite eDNA responded to weather conditions during our study. These findings suggest a need for more study of the ecology of airborne eDNA to uncover its potential for single-species and whole-community research and management in terrestrial ecosystems.

Interactive effects of severe drought and grazing on the life history cycle of a bioindicator species.

We used the lesser prairie-chicken (Tympanuchus pallidicinctus), an iconic grouse species that exhibits a boom-bust life history strategy, on the Southern High Plains, USA, as a bioindicator of main and interactive effects of severe drought and grazing. This region experienced the worst drought on record in 2011. We surveyed lesser prairie-chicken leks (i.e., communal breeding grounds) across 12 years that represented 7 years before the 2011 drought (predrought) and 4 years during and following the 2011 drought (postdrought). Grazing was annually managed with the objective of achieving ≤50% utilization of aboveground vegetation biomass. We used lek (n = 49) count data and covariates of weather and managed grazing to: (a) estimate long-term lesser prairie-chicken abundance and compare abundance predrought and postdrought; (b) examine the influence of annual and seasonal drought (modified Palmer drought index), temperature, and precipitation on long-term lesser prairie-chicken survival and recruitment; and (c) assess and compare the influence of grazing on lesser prairie-chicken population predrought and postdrought. Lesser prairie-chicken abundance was nearly seven times greater predrought than postdrought, and population declines were attributed to decreased survival and recruitment. The number of days with temperature >90th percentile had the greatest effect, particularly on recruitment. The population exhibited a substantial bust during 2011 and 2012 without a boom to recover in four postdrought years. Adaptive grazing positively influenced the population predrought, but had no effects postdrought. Results suggest that the severe drought in 2011 may have been beyond the range of environmental conditions to which lesser prairie-chickens, and likely other species, have adapted. Land management practices, such as grazing, should remain adaptive to ensure potential negative influences to all species are avoided. Increasing habitat quantity and quality by reducing habitat loss and fragmentation likely will increase resiliency of the ecosystem and individual species.

Misidentification of copperhead and cottonmouth snakes following snakebites.

INTRODUCTION: Copperhead (Agkistrodon contortrix) and cottonmouth or water moccasin (Agkistrodon piscivorus) snakes account for the majority of venomous snakebites in the southern United States. Cottonmouth snakes are generally considered to have more potent venom. Copperheads are considered less venomous and there is some controversy as to whether or not bites from copperhead snakes need to be treated with antivenom. Copperhead and juvenile cottonmouth snakes are both brown in color. The purpose of this study was to evaluate the accuracy of identification by the public and healthcare providers between these two species. METHODS: Snakebite victims sometimes bring dead snakes to the hospital or have taken pictures of the snake. When this occurred, ED personnel were asked to take a picture of the snake, and forward the picture to the state poison control center. The identification of the snake by witnesses and/or hospital personnel was compared to the identification by the state herpetologist. RESULTS: During the study period, there were 286 cases of snakebites reported to the state poison control center. Pictures were obtained on 49 of the responsible snakes. All copperhead snakes were identified correctly by callers. However, only 21% of cottonmouth snakes were identified correctly, with 74% of cottonmouth snakes being identified as copperheads. Both public and medical personnel performed poorly on identification of cottonmouth snakes. CONCLUSIONS: Forty percent of the snakes identified as copperheads were actually cottonmouth snakes. Juvenile cottonmouth snakes were often identified as copperhead snakes.

Air Ambulance Delivery and Administration of Four-factor Prothrombin Complex Concentrate Is Feasible and Decreases Time to Anticoagulation Reversal.

OBJECTIVES: The objective was to evaluate the feasibility, safety, and preliminary efficacy of four-factor prothrombin complex concentrate (4-factor PCC) administration by an air ambulance service prior to or during transfer of patients with warfarin-associated major hemorrhage to a tertiary care center for definitive management (interventional arm) compared to patients receiving 4-factor PCC following transfer by air ambulance or ground without 4-factor PCC treatment (conventional arm). METHODS: This was a retrospective chart review of patients presenting to a large academic medical center. All patients presenting to the emergency department (ED) treated with 4-factor PCC from April 1, 2014, through June 30, 2016, were identified. For this study, only transfer patients with an International Normalized Ratio (INR) > 1.5 actively treated with warfarin were included. The primary outcome was the proportion of patients with an INR ≤ 1.5 upon tertiary care hospital arrival, and the secondary efficacy outcome was difference in time to achievement of INR ≤ 1.5. Additional safety and efficacy objectives included difference in thromboembolic complications, length of stay, intensive care unit length of stay, and inpatient mortality between groups. RESULTS: Of the 72 included patients, a higher proportion of patients in the interventional group had an INR ≤ 1.5 on ED arrival (proportion difference = 0.82, 95% confidence interval = 0.64-0.92, p < 0.0001) and significantly reduced time to observed INR ≤ 1.5 (181 minutes vs. 541 minutes, p = 0.001). No differences were observed in thromboembolic complications or patient-centered outcomes with the exception of mortality, which was significantly higher in patients in the interventional group. This group was also observed to have lower Glasgow Coma Scale score and higher intubation rates prior to transfer and treatment. CONCLUSIONS: Dispatch of an air ambulance carrying 4-factor PCC with administration prior to transfer is feasible and leads to more rapid improvement in INR among patients with warfarin-associated major hemorrhage.

Euglycemic Diabetic Ketoacidosis with Elevated Acetone in a Patient Taking a Sodium-Glucose Cotransporter-2 (SGLT2) Inhibitor.

BACKGROUND: Sodium-glucose cotransporter-2 (SGLT2) inhibitor medications are a class of antihyperglycemic agents that increase urinary glucose excretion by interfering with the reabsorption of glucose in the proximal renal tubules. In May of 2015, the U.S. Food and Drug Administration released a warning concerning a potential increased risk of ketoacidosis and ketosis in patients taking these medications. CASE REPORT: We present a case of a 57-year-old woman with type 2 diabetes mellitus taking a combination of canagliflozin and metformin who presented with progressive altered mental status over the previous 2 days. Her work-up demonstrated a metabolic acidosis with an anion gap of 38 and a venous serum pH of 7.08. The serum glucose was 168 mg/dL. The urinalysis showed glucose > 500 mg/dL and ketones of 80 mg/dL. Further evaluation demonstrated an elevated serum osmolality of 319 mOsm/kg and an acetone concentration of 93 mg/dL. She was treated with intravenous insulin and fluids, and the metabolic abnormalities and her altered mental status resolved within 36 h. This was the first episode of diabetic ketoacidosis (DKA) for this patient. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: Diabetic patients on SGLT2 inhibitor medications are at risk for ketoacidosis. Due to the renal glucose-wasting properties of these drugs, they may present with ketoacidosis with only mild elevations in serum glucose, potentially complicating the diagnosis. Acetone is one of the three main ketone bodies formed during DKA and it may be present at considerable concentrations, contributing to the serum osmolality.

Longitudinal Trends in the Prevalence of Diabetes Mellitus in an Urban Emergency Department.

OBJECTIVE: The objective of this study was to examine the longitudinal trends in diabetes mellitus (DM) in emergency department (ED) patients and evaluate the factors associated with those trends. METHODS: We conducted a retrospective analysis of all patients who presented to the ED from 2006 to 2011. The presence of DM, height, and weight were recorded prospectively. The study was conducted in the ED of an urban, academic hospital with an average yearly volume of approximately 62,000 patients. Inclusion criteria were age 16 years and older; presentation to the ED for any reason; and documentation of height, weight, and history of DM. Data were analyzed in 1-year blocks, then examined for trends using linear regression analysis. Data also were examined by obesity class: normal (body mass index [BMI] 20-24.9 kg/m(2)), overweight (BMI 25-29.9 kg/m(2)), obese (BMI 30-39.9 kg/m(2)), and extreme obesity (BMI >40 kg/m(2)). RESULTS: There was a statistically significant increase in the prevalence of type 2 DM during the study period. The percentage of type 2 DM for all patient visits increased progressively from 10.7% to 16.1% (r(2) 0.97). Progressive increases in yearly type 2 DM prevalence were observed for all BMI classes. The rate of change in the increase of DM was related directly to the degree of obesity. For the normal weight category, the percentage of patients with DM increased 0.5%/year (r(2) 0.92), overweight 0.7%/year (r(2) 0.88), obesity 1.0%/year (r(2) 0.90), and extreme obesity 1.4%/year (r(2) 0.94). Patient age increased slightly for all obesity groups, accounting for a 0.2% to 0.4%/year increase in the prevalence of DM in the population. CONCLUSIONS: In this longitudinal analysis, we found an increase in the prevalence of patients with DM and an increase in ED visits by patients with DM. Our results indicate that these increases are influenced most significantly by the obesity level of the patient.

Lead toxicity as an etiology for abdominal pain in the emergency department.

BACKGROUND: Abdominal pain is an uncommon presentation of lead toxicity in the emergency department (ED). However, making the diagnosis is important in avoiding unnecessary testing and the long-term sequelae of lead toxicity. OBJECTIVES: To illustrate possible presentations of abdominal pain secondary to lead toxicity and highlight the importance of taking a thorough patient history. CASE REPORT: We report 2 patients who presented to the ED with abdominal pain and underwent extensive evaluations that did not reveal an etiology. At follow-up visits, their occupational histories revealed possible lead exposures from working for a bullet-recycling company. Tests revealed that each patient had extremely high lead levels and they were both treated for lead toxicity. Their abdominal pain resolved as their lead levels decreased. CONCLUSION: These cases demonstrate a rare but significant cause of abdominal pain in the ED. Although history-taking in the ED is necessarily brief, these cases underscore the importance of obtaining an occupational history.

Inadvertent poisoning of seven teenagers with monosodium methanearsonate.

INTRODUCTION: Monosodium methanearsonate (MSMA) is an organo-arsenic containing herbicide. There is scant information available concerning the toxicity of this chemical in humans. CASE REPORT: Seven male teenagers, 15-18 years of age, inadvertently used a MSMA herbicide as cooking oil to fry fish. All had early gastrointestinal (GI) symptoms. Whole blood arsenic concentrations ranged from 348 to 613 µg/L and initial urine levels ranged from 81 400 to 226 300 µg-arsenic/g-creatinine. They were all treated with dimercaprol for 1 day and succimer for 19 days. They were followed for 15-months and had no evidence of any serious toxicity. CONCLUSION: MSMA produces early GI symptoms and very high levels of arsenic in blood and urine, but no evidence of long-term toxicity.

Blood lead levels in Mississippi children.

Lead is toxic to the nervous system and has been shown to have deleterious effects on the developing nervous systems of children. Widespread exposure to lead has occurred in the past due to the use of lead as a gasoline additive and as a paint additive. Children are usually exposed to lead in the home. Prevention of exposure to lead through monitoring is the most effective way to reduce childhood toxicity. Lead levels were determined in 24,736 children in Mississippi. The percentage of 1-5-year-old children with blood lead levels >10 microg/dL in Mississippi is less than those seen nationally, and mean levels are comparable to national ones. In Mississippi, the age of housing is not a viable predictor of risk for elevated lead levels in children.

Evaluation of potential adverse health effects resulting from chronic domestic exposure to the organophosphate insecticide methyl parathion.

Methyl parathion (MP) was used illegally to spray homes for insect control over approximately an 8-yr period. In an attempt to determine if there were any adverse health effects from this, health-screening evaluations were performed on 353 individuals living in homes that were illegally sprayed. The average subject spent 15.5 h a day in the home. Subjects from homes with high levels of MP (exposure group) were compared to controls that lived in homes with minimal or no MP. Subjects were aware of the levels of MP found in their homes and recall bias was likely. There were no significant differences in the symptoms reported or by the physician assessment of subacute or chronic toxicity between those in the exposure group and controls. No significant differences were found in growth and developmental evaluations. Three subjects were identified who most likely suffered acute toxicity from the initial exposure and were not appropriately diagnosed and treated. Cholinesterase determinations also did not differ between those in the exposure group and controls. When subjects from the exposure group were stratified by the level of MP in their home, those from homes with the highest levels appeared to have an increased likelihood of subacute toxicity and reported an increased number of neuropsychiatric symptoms (OR 2 for both evaluations).

Ethylene glycol toxicity.

Ethylene glycol is an inexpensive, readily available substance that may be associated with accidental or intentional toxicity. Toxicity from this substance may be encountered in the military and civilian populations. Because it is highly toxic and can result in death if not treated appropriately, it is imperative to recognize the signs and symptoms of intoxication. Two cases are presented and the diagnosis and treatment of ethylene glycol toxicity are discussed. Fomepizole, a new medication for ethylene glycol toxicity, has changed the management of this poisoning. It increases the elimination half-life of ethylene glycol, thus delaying the formation of toxic metabolites.

Association between droperidol use and sudden death in two patients intoxicated with illicit stimulant drugs.

Illicit drug intoxication is often a cause of extreme agitation in the emergency department and prehospital settings. Chemical restraint is often required to protect patient as well as health-care providers. Droperidol has commonly been used to sedate extremely agitated patients in the emergency department and psychiatric settings. Its safety has been demonstrated in these settings and in patients who's agitation has been attributed to amphetamine toxicity. We present 2 cases of sudden death following the use of droperidol to sedate 1 patient who was extremely agitated secondary to cocaine intoxication and another secondary to phencyclidine intoxication.

Blunt trauma in the obstetric patient: monitoring practices in the ED.

This study was undertaken to determine the usually used approach to fetal monitoring in the emergency department (ED) of the less severely injured obstetric patient who has sustained blunt trauma. A written survey was sent to clinical directors of teaching programs in emergency medicine (EM) with inquiries on the usual way of monitoring, what studies were performed, and the usual disposition of the less-injured obstetric patient. From the 112 teaching programs surveyed in early 1996, there were 87 responses (78%). Seventy-eight percent of programs generally have fetal monitoring performed for 2 to 4 hours in obstetric trauma patients when the trauma is more than minor extremity injury. In 68%, fetal monitoring was not performed in the ED from the time of the initial assessment of fetal heart tones until the mother went to an obstetric area even though the average estimated time to radiographically clear a cervical spine was 36 minutes. In 92% of programs residents are taught cardiotocographic changes indicative of fetal distress but only 15% have such monitoring equipment in their department. However, 51% do have sonographic equipment in their department. Given a patient with a viable fetus who has no abdominal pain, 46% routinely use fetal monitoring if the mechanism is a simple fall whereas 92% use monitoring only if the mechanism is a rollover motor vehicle collision or a strike to the abdomen. It is generally recognized that fetal distress may occur subtly without overt clinical signs and that obstetric area monitoring for a period of several hours should take place. However, most teaching programs do not institute continuous fetal monitoring during the first 30 to 60 minutes that the mother is undergoing her work-up even though residents are taught such monitoring.