2,760 research outputs found

    Acute Aortic Dissection in Third Trimester Pregnancy without Risk Factors

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    Spontaneous aortic dissection in pregnancy is rare and life threatening for both the mother and the fetus. Most commonly, it is associated with connective tissue disorders, cardiac valve variants, or trauma. We present the case of a 23-year-old previously healthy woman, 36 weeks pregnant with a syncopal episode after dyspnea and vomiting. She subsequently developed cardiac arrest and underwent aggressive resuscitation, emergent thoracotomy, and cesarean delivery without recovery. On autopsy, she was found to have an aortic dissection of the ascending aorta. This case is presented to raise awareness and review the literature and the clinical approach to critical care for pregnant patients

    Fasting and nutrient-stimulated plasma peptide-YY levels are elevated in critical illness and associated with feed intolerance: an observational, controlled study

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    INTRODUCTION: Delayed gastric emptying and feed intolerance occur frequently in the critically ill. In these patients, gastric motor responses to nutrients are disturbed. Peptide YY (PYY) slows gastric emptying. The aim of this study was to determine fasting and nutrient-stimulated plasma PYY concentrations and their relationship to cholecystokinin (CCK) in critically ill patients. METHODS: Studies were performed in 19 unselected mechanically ventilated critically ill patients (12 males; 48 ± 7 years old) in a randomised, single-blind fashion. Subjects received a 60-minute duodenal infusion of Ensure(® )at either 1 or 2 kcal/minute. Blood samples were collected at baseline and at 20, 40, 60, and 180 minutes following commencement of the nutrient infusion for the measurement of plasma PYY and CCK concentrations (using radioimmunoassay). Patient data were compared to 24 healthy subjects (17 males; 43 ± 2 years old). RESULTS: Fasting PYY concentration was higher in patients (P < 0.05), particularly in those with feed intolerance (P < 0.05). Plasma PYY concentrations were higher in patients during nutrient infusion (area under the curve [AUC] at 1 kcal/minute: 2,265 ± 718 versus 1,125 ± 138 pmol/l.min, P < 0.05; at 2 kcal/minute: 2,276 ± 303 versus 1,378 ± 210 pmol/l.min, P = 0.01) compared to healthy subjects. The magnitude of PYY elevation was greater in patients during the 1 kcal/minute infusion (AUC: 441 ± 153 versus 186 ± 58 pmol/l.min, P < 0.05), but not the 2 kcal/minute infusion. Fasting and nutrient-stimulated plasma CCK concentrations were higher in patients (P < 0.05). There was a relationship between plasma PYY and CCK concentrations during fasting (r = 0.52, P < 0.05) and nutrient infusion (r = 0.98, P < 0.0001). CONCLUSION: In critical illness, both fasting and nutrient-stimulated plasma PYY concentrations are elevated, particularly in patients with feed intolerance, in conjunction with increased CCK concentrations

    Интеллектуальная радиосеть с нечеткой конфигурацией

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    В статье обсуждаются возможности применения одноранговой радиосети стандарта IEEE 802.15.4 (ZigBee) диапазона 2,4 ГГц для работы системы, состоящей из группы малогабаритных мобильных роботов и одного командного пункта. Основная задача группы роботов – проведение разведки во время спасательных операций после техногенных и природных катастроф и аварий. Для сохранения управляемости отдельными роботами и системой в целом предлагается повысить «интеллект» системы связи за счет гибкой маршрутизации каналов между командным пунктом и конкретным мобильным роботом с тем, чтобы иметь систему с автоматическим, интеллектуальным восстановлением канала обмена данных.У статті обговорюються можливості застосування однорангової радіомережі стандарту ІЕЕ 802.15.4 (ZigBee) діапазону 2,4 Ггу для роботи системи, що складається з групи малогабаритних мобільних роботів та одного командного пункту. Основна задача групи роботів – проведення розвідки під час рятувальних операцій після техногенних та природних катастроф і аварій. Для збереження керованості окремими ротами та системою в цілому пропонується підвищити інтелект системи зв’язку за рахунок гнучкої маршрутитизації каналів між командним пунктом та конкретним мобільним роботом з тим, щоб мати систему з автоматичним, інтелектуальним відновлюванням каналу обміну даних.In the article the possibilities of application peer-to-peer radio networks of standard IEEE 802.15.4 (ZigBee) a range of 2,4 GHz for work of the system consisting of small-sized mobile robots group and one command point are discussed. The primary goal of group of robots – is carrying out of investigation during rescue operations after technogenic and natural accidents and failures. For controllability preservation by separate robots and system as a whole, it is offered to raise “intelligence” of a communication system at the expense of flexible routeing of channels between command point and the concrete mobile robot to have system with automatic, intellectual restoration of the channel of data exchange

    The relationship between gastric emptying, plasma cholecystokinin, and peptide YY in critically ill patients

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    © 2007 Nguyen et al.; licensee BioMed Central Ltd. This is an open access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.Background Cholecystokinin (CCK) and peptide YY (PYY) are released in response to intestinal nutrients and play an important physiological role in regulation of gastric emptying (GE). Plasma CCK and PYY concentrations are elevated in critically ill patients, particularly in those with a history of feed intolerance. This study aimed to evaluate the relationship between CCK and PYY concentrations and GE in critical illness. Methods GE of 100 mL of Ensure® meal (106 kcal, 21% fat) was measured using a 13C-octanoate breath test in 39 mechanically ventilated, critically ill patients (24 males; 55.8 ± 2.7 years old). Breath samples for 13CO2 levels were collected over the course of 4 hours, and the GE coefficient (GEC) (normal = 3.2 to 3.8) was calculated. Measurements of plasma CCK, PYY, and glucose concentrations were obtained immediately before and at 60 and 120 minutes after administration of Ensure. Results GE was delayed in 64% (25/39) of the patients. Baseline plasma CCK (8.5 ± 1.0 versus 6.1 ± 0.4 pmol/L; P = 0.045) and PYY (22.8 ± 2.2 versus 15.6 ± 1.3 pmol/L; P = 0.03) concentrations were higher in patients with delayed GE and were inversely correlated with GEC (CCK: r = -0.33, P = 0.04, and PYY: r = -0.36, P = 0.02). After gastric Ensure, while both plasma CCK (P = 0.03) and PYY (P = 0.02) concentrations were higher in patients with delayed GE, there was a direct relationship between the rise in plasma CCK (r = 0.40, P = 0.01) and PYY (r = 0.42, P < 0.01) from baseline at 60 minutes after the meal and the GEC. Conclusion In critical illness, there is a complex interaction between plasma CCK, PYY, and GE. Whilst plasma CCK and PYY correlated moderately with impaired GE, the pathogenetic role of these gut hormones in delayed GE requires further evaluation with specific antagonists.Nam Q Nguyen, Robert J Fraser, Laura K Bryant, Marianne J Chapman, Judith Wishart, Richard H Holloway, Ross Butler, and Michael Horowit

    Antigenic characterization of highly pathogenic avian influenza A(H5N1) viruses with chicken and ferret antisera reveals clade-dependent variation in hemagglutination inhibition profiles.

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    Highly pathogenic avian influenza (HPAI) A(H5N1) viruses pose a significant economic burden to the poultry industry worldwide and have pandemic potential. Poultry vaccination against HPAI A(H5N1) viruses has been an important component of HPAI control measures and has been performed in Vietnam since 2005. To systematically assess antigenic matching of current vaccines to circulating field variants, we produced a panel of chicken and ferret antisera raised against historical and contemporary Vietnamese reference viruses representing clade variants that were detected between 2001 and 2014. The antisera were used for hemagglutination inhibition (HI) assays to generate data sets for analysis by antigenic cartography, allowing for a direct comparison of results from chicken or ferret antisera. HI antigenic maps, developed with antisera from both hosts, revealed varying patterns of antigenic relationships and clustering of viruses that were dependent on the clade of viruses analyzed. Antigenic relationships between existing poultry vaccines and circulating field viruses were also aligned with in vivo protection profiles determined by previously reported vaccine challenge studies. Our results establish the feasibility and utility of HPAI A(H5N1) antigenic characterization using chicken antisera and support further experimental and modeling studies to investigate quantitative relationships between genetic variation, antigenic drift and correlates of poultry vaccine protection in vivo

    Early lactate clearance is associated with biomarkers of inflammation, coagulation, apoptosis, organ dysfunction and mortality in severe sepsis and septic shock

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    <p>Abstract</p> <p>Background</p> <p>Lactate clearance, a surrogate for the magnitude and duration of global tissue hypoxia, is used diagnostically, therapeutically and prognostically. This study examined the association of early lactate clearance with selected inflammatory, coagulation, apoptosis response biomarkers and organ dysfunction scores in severe sepsis and septic shock.</p> <p>Methods</p> <p>Measurements of serum arterial lactate, biomarkers (interleukin-1 receptor antagonist, interleukin-6, interleukin-8, interleukin-10, tumor necrosis factor-alpha, intercellular adhesion molecule-1, high mobility group box-1, D-Dimer and caspase-3), and organ dysfunction scores (Acute Physiology and Chronic Health Evaluation II, Simplified Acute Physiology Score II, Multiple Organ Dysfunction Score, and Sequential Organ Failure Assessment) were obtained in conjunction with a prospective, randomized study examining early goal-directed therapy in severe sepsis and septic shock patients presenting to the emergency department (ED). Lactate clearance was defined as the percent change in lactate levels after six hours from a baseline measurement in the ED.</p> <p>Results</p> <p>Two-hundred and twenty patients, age 65.0 +/- 17.1 years, were examined, with an overall lactate clearance of 35.5 +/- 43.1% and in-hospital mortality rate of 35.0%. Patients were divided into four quartiles of lactate clearance, -24.3 +/- 42.3, 30.1 +/- 7.5, 53.4 +/- 6.6, and 75.1 +/- 7.1%, respectively (<it>p </it>< 0.01). The mean levels of all biomarkers and organ dysfunction scores over 72 hours were significantly lower with higher lactate clearance quartiles (<it>p </it>< 0.01). There was a significant decreased in-hospital, 28-day, and 60-day mortality in the higher lactate clearance quartiles (<it>p </it>< 0.01).</p> <p>Conclusions</p> <p>Early lactate clearance as a surrogate for the resolution of global tissue hypoxia is significantly associated with decreased levels of biomarkers, improvement in organ dysfunction and outcome in severe sepsis and septic shock.</p

    Drop impact behaviour on alternately hydrophobic and hydrophilic layered bead packs

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    A high level of water repellency in soils has an impact on soil hydrology, plant growth and soil erosion. Studies have been performed previously on model soils; consisting of close packed layers of glass spheres (140–400 μm in diameter), to mimic the behaviour of rain water on water repellent soils. In this study measurements were performed on multi-layered bead packs, to assess the interaction of water drops impacting layers consisting of different hydrophobic and hydrophilic layers. A high speed video camera was used to record the impact behaviour of water droplets on the bead packs focussing on the spreading of the droplet and the subsequent rebound behaviour of the droplet. Observations were made from the videos of the liquid marble effect on the droplet, whereby hydrophobic particles form a coating around the droplet, and how it differed depending on the arrangement of hydrophobic and hydrophilic layers within the bead pack. The droplet release height was varied in order to establish a relationship between impact velocity and the degree to which liquid marbling occurs, with higher impact speeds leading to a greater degree of liquid marbling. Measurements were also made to find the transition speeds between the three rebound conditions; rebound, pinning and fragmentation, showing an overall decrease in pinning velocity as the bead size increased

    Antibiotic use and prescription and its effects on Enterobacteriaceae in the gut in children with mild respiratory infections in Ho Chi Minh City, Vietnam. A prospective observational outpatient study.

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    BACKGROUND AND OBJECTIVES: Treatment guidelines do not recommend antibiotic use for acute respiratory infections (ARI), except for streptococcal pharyngitis/tonsillitis and pneumonia. However, antibiotics are prescribed frequently for children with ARI, often in absence of evidence for bacterial infection. The objectives of this study were 1) to assess the appropriateness of antibiotic prescriptions for mild ARI in paediatric outpatients in relation to available guidelines and detected pathogens, 2) to assess antibiotic use on presentation using questionnaires and detection in urine 3) to assess the carriage rates and proportions of resistant intestinal Enterobacteriaceae before, during and after consultation. MATERIALS AND METHODS: Patients were prospectively enrolled in Children's Hospital 1, Ho Chi Minh City, Vietnam and diagnoses, prescribed therapy and outcome were recorded on first visit and on follow-up after 7 days. Respiratory bacterial and viral pathogens were detected using molecular assays. Antibiotic use before presentation was assessed using questionnaires and urine HPLC. The impact of antibiotic usage on intestinal Enterobacteriaceae was assessed with semi-quantitative culture on agar with and without antibiotics on presentation and after 7 and 28 days. RESULTS: A total of 563 patients were enrolled between February 2009 and February 2010. Antibiotics were prescribed for all except 2 of 563 patients. The majority were 2nd and 3rd generation oral cephalosporins and amoxicillin with or without clavulanic acid. Respiratory viruses were detected in respiratory specimens of 72.5% of patients. Antibiotic use was considered inappropriate in 90.1% and 67.5%, based on guidelines and detected pathogens, respectively. On presentation parents reported antibiotic use for 22% of patients, 41% of parents did not know and 37% denied antibiotic use. Among these three groups, six commonly used antibiotics were detected with HPLC in patients' urine in 49%, 40% and 14%, respectively. Temporary selection of 3rd generation cephalosporin resistant intestinal Enterobacteriaceae during antibiotic use was observed, with co-selection of resistance to aminoglycosides and fluoroquinolones. CONCLUSIONS: We report overuse and overprescription of antibiotics for uncomplicated ARI with selection of resistant intestinal Enterobacteriaceae, posing a risk for community transmission and persistence in a setting of a highly granular healthcare system and unrestricted access to antibiotics through private pharmacies. REGISTRATION: This study was registered at the International Standard Randomised Controlled Trials Number registry under number ISRCTN32862422: http://www.isrctn.com/ISRCTN32862422
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