Matthew R. Lewin

A giant ornithomimosaur from the Early Cretaceous of China

Ornithomimosaurs (ostrich-mimic dinosaurs) are a common element of some Cretaceous dinosaur assemblages of Asia and North America. Here, we describe a new species of ornithomimosaur, Beishanlong grandis, from an associated, partial postcranial skeleton from the Aptian-Albian Xinminpu Group of northern Gansu, China. Beishanlong is similar to another Aptian-Albian ornithomimosaur, Harpymimus, with which it shares a phylogenetic position as more derived than the Barremian Shenzhousaurus and as sister to a Late Cretaceous clade composed of Garudimimus and the Ornithomimidae. Beishanlong is one of the largest definitive ornithomimosaurs yet described, though histological analysis shows that the holotype individual was still growing at its death. Together with the co-eval and sympatric therizinosaur Suzhousaurus and the oviraptorosaur Gigantraptor, Beishanlong provides evidence for the parallel evolution of gigantism in separate lineages of beaked and possibly herbivorous coelurosaurs within a short time span in Central Asia.

Digital preparation of a probable neoceratopsian preserved within an egg, with comments on microstructural anatomy of ornithischian eggshells

We describe the first known embryo of a neoceratopsian dinosaur, perhaps the most ubiquitous Laurasian group of Cretaceous dinosaurs, which is preserved completely enclosed within an egg. This specimen was collected from Late Cretaceous beds of southern Mongolia, which commonly preserve fossils of the neoceratopsian, Yamaceratops dorngobiensis. The small egg was scanned using high-resolution X-ray computed tomography and digitally prepared from the matrix. The preserved and imaged elements support a diagnosis of the embryo to Neoceratopsia and allow preliminary observations of ontogenetic transformations within this group. The addition of an embryo also adds another important data point to the already impressive postnatal ontogenetic series that are available for this clade.

Nonsyndromic Genetic Predisposition to Aortic Dissection: A Newly Recognized, Diagnosable, and Preventable Occurrence in Families

The major diseases affecting the aorta are aortic aneurysms and dissections, with patients with acute dissections often presenting in the emergency department (ED). Recent studies demonstrate a strong genetic predisposition to thoracic aortic aneurysms and dissections, independent of syndromes traditionally considered to predispose to aortic disease (such as Marfan syndrome). Nonsyndromic familial thoracic aortic aneurysms and dissections are inherited in families as an autosomal dominant disorder and a variable age of onset of the aortic disease. The case reported here illustrates the critical importance of obtaining a family history of thoracic aortic aneurysms and dissections, along with unexplained sudden death, when assessing an individual with chest pain in the ED, regardless of age and in the absence of a known genetic syndrome.

Rickettsia sibirica infection in members of scientific expeditions to northern Asia

The risk of acquiring North Asian tick typhus (infection by Rickettsia sibirica) during travel to regions of Asia where this disease is endemic is unknown. We investigated prospectively 13 paleontologists on expedition to Mongolia. Four paleontologists had acute illness characterised by fever, rash, headache, and lymphadenopathy. All had IgM and IgG antibodies to R sibirica. Paleontologists with no illness and people who went on expeditions in other parts of the world did not have antibodies to R sibirica. Only two of the four infected persons were aware of tick bites. Travellers to regions endemic for R sibirica are at risk of contracting North Asian tick typhus even in the absence of recognised tick-bites.

Varespladib (LY315920) Appears to Be a Potent, Broad-Spectrum, Inhibitor of Snake Venom Phospholipase A2 and a Possible Pre-Referral Treatment for Envenomation

Snakebite remains a neglected medical problem of the developing world with up to 125,000 deaths each year despite more than a century of calls to improve snakebite prevention and care. An estimated 75% of fatalities from snakebite occur outside the hospital setting. Because phospholipase A2 (PLA2) activity is an important component of venom toxicity, we sought candidate PLA2 inhibitors by directly testing drugs. Surprisingly, varespladib and its orally bioavailable prodrug, methyl-varespladib showed high-level secretory PLA2 (sPLA2) inhibition at nanomolar and picomolar concentrations against 28 medically important snake venoms from six continents. In vivo proof-of-concept studies with varespladib had striking survival benefit against lethal doses of Micrurus fulvius and Vipera berus venom, and suppressed venom-induced sPLA2 activity in rats challenged with 100% lethal doses of M. fulvius venom. Rapid development and deployment of a broad-spectrum PLA2 inhibitor alone or in combination with other small molecule inhibitors of snake toxins (e.g., metalloproteases) could fill the critical therapeutic gap spanning pre-referral and hospital setting. Lower barriers for clinical testing of safety tested, repurposed small molecule therapeutics are a potentially economical and effective path forward to fill the pre-referral gap in the setting of snakebite.

The seasonality of acute coronary syndrome and its relations with climatic parameters

BACKGROUND Most research on the seasonality of acute coronary syndrome (ACS) has been were reported from hospital-based data. We aimed to investigate the seasonal distribution of ACS in Beijing and to elucidate the relations between ACS occurrence and climatic parameters in a prehospital setting. METHODS We retrospectively reviewed the electronic prehospital medical records from the Beijings emergency medical service system spanning August 1, 2005, to July 31, 2007. Case data were analyzed by month and season with χ² test. The effects of climatic factors on the occurrence of ACS were analyzed by Poisson regression with generalized linear model. RESULTS During the 2-year study period, a total of 7037 ACS events were identified, including 4135 male patients (58.8%) and 2902 female patients (41.2%). Significant variations were observed in the monthly (P < .001) and seasonal (P < .001) distribution of ACS. The highest seasonal incidence occurred in winter and lowest in autumn. Significant negative correlations were noticed between the number of ACS events and daily mean temperature (P < .001) and between the number of ACS events and barometric pressure (P < .001). Comparing to the baseline level (temperature of 25°C to approximately 31°C; barometric pressure of 1026 to approximately 1048 hectopascal (hPa)), an increase of 41.3% of daily ACS incidence was associated with temperature lower than 2°C (-10.0°C to approximately 2.0°C), and an increase of 19.8% was associated with barometric pressure under 1006 hPa (991.0 to approximately 1006 hPa). CONCLUSIONS There are clear monthly and seasonal rhythms of ACS in Beijing metropolitan area. Temperature and barometric pressure are negatively related with the occurrence of ACS.

Diagnostic nuclear medicine in the ED

Although the decision to use nuclear medicine (NM) modalities in the acute care setting is limited by several factors, there are instances in which the use of NM techniques can provide elegant and efficient solutions to otherwise expensive and resource consuming situations. Herein, we describe the indications and NM techniques used for the evaluation of low-risk patients with chest pain, suspected pulmonary embolus, acute cholecystitis, gastrointestinal bleeding, acute scrotum, and the radiographically occult fracture.

A case and review of noma.

History and Epidemiology Historically, noma is a disease of extreme poverty and malnourishment, reported throughout history in Asia, Europe, South America, and Africa [1,3,4]. It was described by Hippocrates [5] and found in German and Japanese concentration camps during World War II [1,6]. Infection occurs mostly in children, although it has been described in neonates, adults, and the chronically ill [3,7]. The true prevalence and incidence of noma are not fully known, because it is believed that only ,15% of patients with acute cases of the disease seek medical care [1,8]. Noma is a disease of shame, and the condition often results in forced isolation from the community and family; many children are sent to live in isolation rather than being taken to medical care [1,8–10]. In the late 1990s, the incidence of acute childhood noma was placed at 25,600 in countries bordering the Sahara [11], and worldwide at between 100,000 and 140,000 per year, primarily in sub-Saharan Africa and Asia [12]. Peak incidence is among children aged 1–4 [3,4,7]. Worldwide prevalence of those living with the sequelae of noma was placed at 770,000 in 1997 [8].

Improvised Cricothyrotomy Provides Reliable Airway Access in an Unembalmed Human Cadaver Model

Abstract Objective.—Patients with injuries requiring surgical airway management occurring far from medical care might benefit from the availability of a simple, reliable, improvisational method of cricothyrotomy with materials available in a wilderness or prehospital setting. We evaluated an improvised cricothyrotomy device in an experimental, unembalmed human cadaver model. Methods.—A high-flow intravenous spike and drip chamber was cut through the drip chamber and used as the sole apparatus for performing cricothyrotomy on unembalmed cadavers whose anterior neck surfaces and deep tissues were warmed to or near body temperature. Correct placement in the trachea and damage to the posterior wall of the trachea were assessed by either fiberoptic bronchoscopy or neck dissection. Video recordings were used to time each procedure. Each operator was responsible for both device insertion and bag valve mask attachment and ventilation, modeling as the sole care provider for the patient. Results.—One physician and 3 emergency medicine residents, all without previous, specific instruction, performed 10 procedures on 5 female and 5 male unembalmed cadavers weighing a mean of 65 kg (range 45–110 kg). All 10 attempts at placement of the intravenous tubing spike through the cricothyroid membrane were successful. On 2 attempts, the initial placement of the device was incorrect, but the error was immediately identified on attempt to ventilate the patient. Repositioning of the device resulted in appropriate cannulation of the trachea in both attempts. The median time span from manual identification of the cricothyroid membrane to percutaneous access and connection of the bag valve mask with successful ventilation was 27.3 seconds. Violation of the posterior tracheal wall was not seen on any of the 5 procedures in which fiberoptic visualization was available or in the 5 procedures evaluated by neck dissection. Conclusions.—Cricothyrotomy is the quickest and most effective method for obtaining airway access when nonsurgical methods of securing the airway are contraindicated or fail. Although frequently described, no improvised airway devices of this type have been tested in a systematic manner. We tested the reliability and utility of cricothyrotomy with a high-flow intravenous spike and drip chamber. Our results suggest that the spike and drip chamber is a plausible means of temporarily establishing airway access in patients with acute airway obstruction in a wilderness or prehospital environment.

Circadian, day-of-week, and age patterns of the occurrence of acute coronary syndrome in Beijing's emergency medical services system

Abstract Background Previous in-hospital studies suggest that there are significant circadian rhythms associated with the incidence of acute coronary syndromes (ACSs). No study to date has examined the presentation of ACS in the prehospital setting. Our goal was to examine circadian, day-of-week, and age patterns of occurrence in ACS in a large, urban emergency medical services (EMS) system. Methods We retrospectively reviewed the electronic prehospital medical records from the Beijings EMS system spanning August 1, 2005, to July 31, 2007. Data were analyzed by hour of the day and day of the week. χ 2 tests were performed to compare the difference. Results Seven thousand thirty-two cases of ACS were identified by the EMS system physicians during the 2-year study period, including 536 cases of acute myocardial infarction. A significant variation of circadian distribution of ACS was observed in both 24-hour (P < .001) and 2-hour (P < .001) interval time course. Two peaks were observed in the morning from 0800 to 1000 and approaching midnight from 2200 to 2400. Increases of 50% and 60.8% in the morning and evening peaks were found, respectively, when compared with the early morning baseline (nadir). No significant difference was found among the accumulated cases in 2 years on each day in a week (P = .203). Conclusions Our study shows that, in the Beijing metropolitan area, the presentation of ACS has significant circadian rhythm characterized by 2 peaks within 24 hours, the morning peak is 0800 to 1000, and the late evening peak is 2200 to 2400. No significant weekly rhythm was observed in the present study.