Cervical Artery Dissections and Ischemic Strokes Associated with Vascular Neck Compression Techniques (Sportive Chokes).

BACKGROUND: Strangulation as a fight-finishing maneuver in combat sports, termed "choking" in that context, occurs worldwide millions of times yearly. This activity can be trained safely, but devastating injuries can occur. OBJECTIVE: Our aim was to present a case series of cervical artery dissections and ischemic strokes associated with sportive choking. Sharing these cases is meant to draw awareness, to assist emergency physicians in caring for these athletes, and to provide a platform for further research. METHODS: Institutional Review Board approval was obtained. Participants consented for medical information transfer and anonymous academic reproduction. The minimum medical record information necessary for inclusion was a report of diagnosis-confirming advanced imaging. Participants were contacted for primary information in addition to what the medical records could provide and to confirm some information in the record (e.g., pertinent medical history, demographic characteristics, choking event description, medical care, and commentary on their current health). Medical records and additional first-hand information were reviewed and participants were included if they had a diagnosed dissection or stroke likely associated with a sportive choke. RESULTS: Ten cases met all criteria for inclusion. There were 5 cases of carotid artery dissection, 3 cases of vertebral artery dissection, and 2 cases of ischemic stroke without dissection. Nine of 10 participants survived and 3 of 10 have returned to submission grappling training. CONCLUSIONS: Cervical artery dissections and ischemic strokes can occur in association with sportive choking. Emergency physicians must be aware of the widespread nature of this activity and must be vigilant in approaching management of patients with symptoms consistent with these injuries.

The force-temperature relationship in healthy and dystrophic mouse diaphragm; implications for translational study design.

In the field of muscular dystrophy, striated muscle function is often assessed in vitro in dystrophin-deficient mdx mice in order to test the impact of a potential treatment strategy. Although many past studies have assessed diaphragm contractile function at or near room temperature, the diaphragm performs in vivo at 37°C. To improve translation of bench-top results to possible clinical application, we studied temperature-dependence of contractile performance in wild-type (C57BL/10) and mdx muscle strips at temperatures from 25°C to 37°C. Maximal tetanic force in wild-type muscles was higher at 37°C (198 ± 11 vs. 155 ± 9 mN/mm(2) at 25°C), while the difference between wild-type and mdx was extremely similar: wild-type muscles produced 45.9% and 45.1% more force at 25°C and 37°C respectively. At 37°C twitch contraction kinetics and 50% rise time to tetanic plateau were slower in mdx diaphragm. A fatigue/injury protocol indicated 2-fold fatigue/contraction-induced force deficit in mdx muscles. We conclude that assessment of diaphragm muscle strips can be reliably and reproducibly performed at 37°C.

Early treatment with lisinopril and spironolactone preserves cardiac and skeletal muscle in Duchenne muscular dystrophy mice.

BACKGROUND: Nearly universal cardiomyopathy in Duchenne muscular dystrophy (DMD) contributes to heart failure and death. Because DMD patients show myocardial fibrosis well before functional impairment, we postulated that earlier treatment using drugs with antifibrotic effect may be beneficial. METHODS AND RESULTS: Three groups of 10 utrn(+/-);mdx, or "het" mice, deficient for dystrophin and haploinsufficient for utrophin with skeletal myopathy and cardiomyopathy that closely mimics clinical DMD were studied. One het group received spironolactone and lisinopril starting at 8 weeks of life (het-treated-8); a second received the same starting at 4 weeks of life (het-treated-4), and the third het group was untreated. At 20 weeks, all mice had normal ejection fractions though circumferential strain rate was abnormal (-0.21±0.08) in untreated hets. This improved to -0.40±0.07 in het-treated-8 mice (P=0.003) and further improved to -0.56±0.10 in het-treated-4 mice (P=0.014 for het-treated-4 versus het-treated-8). Treated mice showed less cardiomyocyte damage, with a 44% reduction in intracardiomyocyte serum immunoglobulin G localization in het-treated-8 mice (P<0.0001) and a further 53% reduction in het-treated-4 mice (P=0.0003 versus het-treated-8); matrix metalloproteinases were similarly reduced. Cardiac, limb, and diaphragm function by ex vivo muscle testing remained at 80% of normal with early treatment compared to a decline to 40% of normal skeletal muscle function without treatment. CONCLUSIONS: These findings offer clinically available medications with proven antifibrotic effect as a new therapeutic strategy in DMD. Early initiation greatly attenuated myocardial disease and, for the first time with these drugs, improved skeletal myopathy. Thus, early initiation of such agents warrants further clinical evaluation to maintain ambulatory, respiratory, and cardiac function for patients with DMD and related myopathies.

An ancient nova shell around the dwarf nova Z Camelopardalis.

Cataclysmic variables (classical novae and dwarf novae) are binary star systems in which a red dwarf transfers hydrogen-rich matter, by way of an accretion disk, to its white dwarf companion. In dwarf novae, an instability is believed to episodically dump much of the accretion disk onto the white dwarf. The liberation of gravitational potential energy then brightens these systems by up to 100-fold every few weeks or months. Thermonuclear-powered eruptions thousands of times more luminous occur in classical novae, accompanied by significant mass ejection and formation of clearly visible shells from the ejected material. Theory predicts that the white dwarfs in all dwarf novae must eventually accrete enough mass to undergo classical nova eruptions. Here we report a shell, an order of magnitude more extended than those detected around many classical novae, surrounding the prototypical dwarf nova Z Camelopardalis. The derived shell mass matches that of classical novae, and is inconsistent with the mass expected from a dwarf nova wind or a planetary nebula. The shell observationally links the prototypical dwarf nova Z Camelopardalis with an ancient nova eruption and the classical nova process.

Ernest Hemingway: a psychological autopsy of a suicide.

Much has been written about Ernest Hemingway, including discussion of his well-documented mood disorder, alcoholism, and suicide. However, a thorough biopsychosocial approach capable of integrating the various threads of the author's complex psychiatric picture has yet to be applied. Application of such a psychiatric view to the case of Ernest Hemingway in an effort toward better understanding of the author's experience with illness and the tragic outcome is the aim of this investigation. Thus, Hemingway's life is examined through a review and discussion of biographies, psychiatric literature, personal correspondence, photography, and medical records. Significant evidence exists to support the diagnoses of bipolar disorder, alcohol dependence, traumatic brain injury, and probable borderline and narcissistic personality traits. Late in life, Hemingway also developed symptoms of psychosis likely related to his underlying affective illness and superimposed alcoholism and traumatic brain injury. Hemingway utilized a variety of defense mechanisms, including self-medication with alcohol, a lifestyle of aggressive, risk-taking sportsmanship, and writing, in order to cope with the suffering caused by the complex comorbidity of his interrelated psychiatric disorders. Ultimately, Hemingway's defense mechanisms failed, overwhelmed by the burden of his complex comorbid illness, resulting in his suicide. However, despite suffering from multiple psychiatric disorders, Hemingway was able to live a vibrant life until the age of 61 and within that time contribute immortal works of fiction to the literary canon.

A laboratory-based study to assess the performance of surgical gloves.

The inherent tear resistance and elasticity of latex and the touch sensitivity it provides has made it the traditional material of choice for surgical gloves, protecting both health care workers and patients from the transmission of bloodborne infections. Although increased incidence of latex allergy has led to increased use of nonlatex surgical gloves, the effectiveness of these gloves as a barrier to infection has not been examined thoroughly. This laboratory-based study compared the performance of latex and nonlatex surgical gloves in a simulated stress protocol. The propensity of surgical gloves to fail was dependent on glove material, manufacturer, and stress. Nonlatex neoprene and nitrile gloves were comparable to latex and can provide a good alternative to latex for allergic patients and health care workers. In this study, isoprene was found to be inferior to latex and other nonlatex materials. The presence or absence of glove powder had no significant influence on the probability of glove failure.

Performance of latex and nonlatex medical examination gloves during simulated use.

BACKGROUND: In response to the rise in latex allergies, gloves made from a variety of nonlatex materials have been introduced into the health care environment. To date, at least 1 study, by Rego and Roley (1999), has reported that both latex and nitrile medical examination gloves provide comparable barrier protective qualities. The purpose of our study was to determine the effects of glove stress, type of material (vinyl, nitrile, copolymer, latex), and manufacturer on the barrier effectiveness of medical examination gloves. METHOD: A total of 5510 medical examination gloves (1464 nitrile, 1052 latex, 1006 copolymer, and 1988 vinyl) were divided into 2 groups: stressed and unstressed. Unstressed gloves were visually inspected and water-tested according to the Food and Drug Administration water-testing standards. Stressed gloves were manipulated according to a designated stress protocol, visually inspected, and then subjected to the same Food and Drug Administration water-testing standards. RESULTS: Our limited sample size demonstrated that nitrile gloves had the lowest failure rate (1.3%), followed by latex (2.2%); vinyl and copolymer gloves had the highest failure rate (both 8.2%). With use of a logistic regression analysis adjusting for manufacturer and stress, latex examination gloves were found to be 3 times more likely to fail than nitrile gloves (odds ratio, 3.2; 95% CI, 1.37-7.50). Nitrile gloves were also found to fail significantly less often than vinyl or copolymer gloves (odds ratio, 12.60; 95% CI, 5.80-27.40). CONCLUSIONS: Nitrile examination gloves are a suitable alternative to latex, whereas vinyl and copolymer examination gloves were found to be less effective barriers. Further research is indicated to determine whether nitrile gloves can provide effective barrier qualities during clinical use versus laboratory simulations.