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Background Preoperative L-lactatemia and heart rate have been suggested as prognostic indicators of outcome for cows with right dilatation of the abomasum or volvulus ( RDA/ AV). However, postoperative L-lactatemia has not been assessed as a potential prognostic tool. Objectives To determine the prognostic value of postoperative L-lactatemia ( LAC2), duration of treatment (Dt), relative L-lactatemia difference (compared with preoperative L-lactatemia [LAC1]) ([LAC2 − LAC1]/LAC2) and change in L-lactate over time ([LAC2 − LAC1]/Dt) as compared to preoperative findings ( LAC1 and heart rate [ HR]) as prognostic factors in dairy cows with RDA/ AV. Animals A total of 41 dairy cows were included: 19 with AV and 22 with RDA; 11 cows had a negative outcome ( NO) and 30 cows had a positive outcome ( PO) based on telephone follow-up with owners 30 days after surgery. Methods Prospective cohort study. Analysis was performed using logistic regression and comparison of area under the receiver operating characteristics curve ( AUC) using nonparametric tests. Results LAC1 > 1.4 mmol/L or LAC2 > 2.2 mmol/L had the same accuracy with sensitivity of 100% (95% CI, 75.1-100%) and specificity of 80% (95% CI, 61.4-92.3%) for predicting NO. The relative L-lactatemia difference ([LAC2 − LAC1]/LAC1) or lactate kinetics ([LAC2 − LAC1]/Dt) were not associated with prognosis. The AUC of the preoperative model (which included HR and lnLAC1) was 0.92 (95% CI, 0.83-1.0) and that of the postoperative model (including only lnLAC2) was 0.95 (95% CI, 0.88-1.0); these were not significantly different. Conclusions and Clinical Importance Postoperative L-lactatemia is helpful to predict outcome in cows with RDA/ AV. The short-term change in blood L-lactate is not a useful prognostic indicator , at least during the period of time spent on the farm for surgery and treatment. [ABSTRACT FROM AUTHOR]

The objectives of the current study were (1) to determine the gain in prognostic accuracy of preoperative L-lactate concentration (LAC) measured on farm on cows with right displaced abomasum (RDA) or abomasal volvulus (AV) for predicting negative outcome; and (2) to suggest clinically relevant thresholds for such use. A cohort of 102 cows with on-farm surgical diagnostic of RDA or AV was obtained from June 2009 through December 2011. Blood was drawn from coccygeal vessels before surgery and plasma LAC was immediately measured by using a portable clinical analyzer. Dairy producers were interviewed by phone 30 d following surgery and the outcome was determined: a positive outcome if the owner was satisfied of the overall evolution 30 d postoperatively, and a negative outcome if the cow was culled, died, or if the owner reported being unsatisfied 30 d postoperatively. The area under the curve of the receiver operating characteristic curve for LAC was 0.92 and was significantly greater than the area under the curve of the receiver operating characteristic curve of heart rate (HR; 0.77), indicating that LAC, in general, performed better than HR to predict a negative outcome. Furthermore, the ability to predict a negative outcome was significantly improved when LAC measurement was considered in addition to the already available HR data (area under the curve: 0.93 and 95% confidence interval: 0.87, 0.99). Important inflection points of the misclassification cost term function were noted at thresholds of 2 and 6 mmol/L, suggesting the potential utility of these cut-points. The 2 and 6 mmol/L thresholds had a sensitivity, specificity, positive predictive value, and negative predictive value for predicting a negative outcome of 76.2, 82.7, 53.3, and 93.1%, and of 28.6, 97.5, 75, and 84%, respectively. In terms of clinical interpretation, LAC ≤2 mmol/L appeared to be a good indicator of positive outcome and could be used to support a surgical treatment decision. The treatment decision for cows with LAC between 2 and 6 mmol/L, however, would depend on the economic context and the owner's attitude to risk in regard to potential return on its investment. Finally, performing a surgical correction on commercial cows with RDA or AV and a LAC ≥6 mmol/L appeared to be unjustified and these animals should be culled based on their high probability of negative outcome. [ABSTRACT FROM AUTHOR]

Objective: How risk factors for sudden infant death syndrome (SIDS) interrelate is not clear. Perhaps normal brain-cooling mechanisms are frustrated. Some mammals have selective brain cooling. Scrutiny of the relationship between body core and brain temperatures in mammals with cerebral vascular systems like man was planned.Design/sample: Pilot studies were undertaken in five rabbits (Orytolagus cuniculus) and three monkeys (Macaca mulatta). The first showed that the parietal lobe of the brain was cooled relative to rectal temperature while the body was being heated which suggested that brain cooling might be mediated by cooled carotid arterial blood.Measurements: In the monkeys (10.5-11.4 kg) direct temperature measurements (calibration against the internal carotid thermocouple to an accuracy of 0.2 degrees C for the right cerebral hemisphere and 0.15 degrees C for the left: r= 0.99, P < 0.001) were monitored in the internal carotid, the brain and the rectum, as well as room air. Monkeys were anaesthetized, not intubated and breathing spontaneously, heavily wrapped and laid on a heated pig farrowing pad. In one monkey the subsequent period of cooling was interrupted by causing the monkey to breathe warm air from a hair dryer.Results: Internal carotid blood was found to be 1.5-2.0 degrees C cooler than body core, presumably because of its proximity to the respiratory airway. Brain temperature remained substantially hotter than carotid blood. Both rose as the body temperature increased to 39.5-40.8 degrees C, at which point brain temperature rise began to outstrip the rises in the body and carotid blood, presumably due to brain metabolism.Conclusions and implications: When body heating was withdrawn, all temperatures fell, but on breathing warmed air, although rectal temperature continued to fall, carotid and brain temperature again rose.Carotid blood limits the rise of cerebral temperature caused by brain metabolism. The conditions under which this mechanism may fail include body core pyrexia and a rise in inspired air temperature. The phenomenon may explain the operation of risk factors for SIDS. Further implications suggest a related cooling mechanism for the brainstem and lead to questions about cooling of the uterus during pregnancy. [ABSTRACT FROM AUTHOR]

Introduction La coagulation intravasculaire disséminée (CIVD) est une anomalie acquise de la coagulation relativement fréquente en réanimation, notamment lors du sepsis, et grevée d’une mortalité élevée. Le score ISTH est un score biologique permettant le diagnostic de CIVD. Il se calcule à partir de 4 paramètres biologiques : plaquettes, temps de Quick, fibrinogène et un marqueur de dégradation de la fibrine. Ce dernier est laissé au choix du laboratoire parmi les monomères de fibrine (MF), les produits de dégradation de la fibrine (PDF) ou les D-Dimères. Certaines études ont montré qu’utiliser le dosage des MF permettait d’améliorer la valeur pronostique du score ISTH [1] . Les dosages des MF et des D-Dimères se font sur des automates, alors que celui des PDF utilise une méthode manuelle. Dans un contexte de réorganisation de la biologie médicale de notre hôpital, nous avons cherché à étudier les performances diagnostiques du score ISTH en utilisant les MF et les D-Dimèrescomparativement aux PDF, méthode de référence actuelle. Matériel et méthodes Après accord du CPP, étude prospective observationnelle, incluant les patients présentant un syndrome de réponse inflammatoire systémique (SIRS) dans un service de réanimation durant 4 mois. Un bilan de coagulation était prélevé lors de l’apparition du SIRS avec comme marqueurs de dégradation de la fibrine les MF, les D-Dimères et les PDF. Pour le calcul du score ISTH, les valeurs permettant de déterminer une élévation modérée (2 points) et importante (3 points) étaient pour les D-Dimères 0,5 mg/L et 4 mg/L, pour les MF 5 mg/L et 10 mg/L et pour les PDF 10 mg/L et 20 mg/L. Les scores ISTH ont ensuite été calculés pour chaque prélèvement avec ces 3 marqueurs puis comparés. Un coefficient de corrélation de Spearman et un graphique en nuage de points étaient réalisés entre les scores ISTH calculés avec MF/D-Dimères, MF/PDF et D-Dimères/PDF ( Fig. 1 ). Résultats Ont été inclus 25 patients. Les coefficients de corrélations des scores ISTH selon le marqueur de dégradation de la fibrine utilisé sont représentés dans le Tableau 1 . Discussion Le degré de corrélation entre les scores ISTH calculés avec les 3 marqueurs est bon. Le calcul du score ISTH avec les FM et D-Dimères comme marqueurs de dégradation de la fibrine, semble au moins aussi performant que le dosage des PDF. L’utilisation de marqueurs automatisés (FM et D-Dimères) permettrait un calcul et un rendu systématique par le laboratoire, en comparaison à la technique manuelle utilisant les PDF. [ABSTRACT FROM AUTHOR]

Objective: Pertussis toxin uncoupling-based studies have shown that Gαi and Gαo can inhibit insulin secretion in pancreatic β-cells. Yet it is unclear whether Gαi and Gαo operate through identical mechanisms and how these G-protein-mediated signals inhibit insulin secretion in vivo. Our objective is to examine whether/how Gαo regulates islet development and insulin secretion in β-cells.Research Design and Methods: Immunoassays were used to analyze the Gαo expression in mouse pancreatic cells. Gαo was specifically inactivated in pancreatic progenitor cells by pancreatic cell-specific gene deletion. Hormone expression and insulin secretion in response to different stimuli were assayed in vivo and in vitro. Electron microscope and total internal reflection fluorescence-based assays were used to evaluate how Gαo regulates insulin vesicle docking and secretion in response to glucose stimulation.Results: Islet cells differentiate properly in Gαo(-/-) mutant mice. Gαo inactivation significantly enhances insulin secretion both in vivo and in isolation. Gαo nullizygous β-cells contain an increased number of insulin granules docked on the cell plasma membrane, although the total number of vesicles per β-cell remains unchanged.Conclusions: Gαo is not required for endocrine islet cell differentiation, but it regulates the number of insulin vesicles docked on the β-cell membrane. [ABSTRACT FROM AUTHOR]

SummaryMisplacement of a central venous catheter may lead to myocardial perforation and dysrhythmia. Atrial electrocardiography (ECG) through a saline column is an effective but complex method to determine the accurate location of catheters. We evaluated a simplified variant of this technique using the guidewire as an internal electrode in 23 children (5–16 years old) undergoing spinal surgery. Catheters were placed using a Seldinger technique after jugular or subclavian venous puncture. Each time the operator recognized the atrial signal, the catheter was found to be correctly placed on the chest radiograph (20/23). In three patients, the atrial signal was not obtained. A technical error was responsible in one case whereas the two others were related to aberrant migrations of the catheter either into a subclavian vein or into the pleura. In this latter case, the complication was unrecognized on the first radiograph despite malposition having been predicted by atrial ECG. We conclude that a method using atrial ECG guidance is sensitive and specific, and may be an alternative to the classical chest radiograph to detect accurate placement of central venous catheters in children. [ABSTRACT FROM AUTHOR]

Objective How risk factors for sudden infant death syndrome (SIDS) interrelate is not clear. Perhaps normal brain-cooling mechanisms are frustrated. Some mammals have selective brain cooling. Scrutiny of the relationship between body core and brain temperatures in mammals with cerebral vascular systems like man was planned. Design/sample Pilot studies were undertaken in five rabbits (Orytolagus cuniculus) and three monkeys (Macaca mulatta). The first showed that the parietal lobe of the brain was cooled relative to rectal temperature while the body was being heated which suggested that brain cooling might be mediated by cooled carotid arterial blood. Measurements In the monkeys (10.5–11.4 kg) direct temperature measurements (calibration against the internal carotid thermocouple to an accuracy of 0.2 °C for the right cerebral hemisphere and 0.15 °C for the left: r = 0.99, P < 0.001) were monitored in the internal carotid, the brain and the rectum, as well as room air. Monkeys were anaesthetized, not intubated and breathing spontaneously, heavily wrapped and laid on a heated pig farrowing pad. In one monkey the subsequent period of cooling was interrupted by causing the monkey to breathe warm air from a hair dryer. Results Internal carotid blood was found to be 1.5–2.0 °C cooler than body core, presumably because of its proximity to the respiratory airway. Brain temperature remained substantially hotter than carotid blood. Both rose as the body temperature increased to 39.5–40.8 °C, at which point brain temperature rise began to outstrip the rises in the body and carotid blood, presumably due to brain metabolism. When body heating was withdrawn, all temperatures fell, but on breathing warmed air, although rectal temperature continued to fall, carotid and brain temperature again rose. Conclusions and implications Carotid blood limits the rise of cerebral temperature caused by brain metabolism. The conditions under which this... [ABSTRACT FROM AUTHOR]