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A living cell actively generates traction forces on its environment with its actin cytoskeleton. These forces deform the cell elastic substrate which, in turn, affects the traction forces exerted by the cell and can consequently modify the cell dynamics. By considering a cell constrained to move along a one-dimensional thin track, we take advantage of the problem geometry to explicitly derive the effective law that describes the non-local frictional contact between the cell and the deformable substrate. We then couple such a law with one of the simplest model of the active flow within the cell cytoskeleton. This offers a paradigm that does not invoke any local non-linear friction law to explain that the relation between the cell steady state velocity and the substrate elasticity is non linear as experimentally observed. Additionally, we present an experimental platform to test our theoretical predictions. While our efforts are still not conclusive in this respect as more cell types need to be investigated, our analysis of the coupling between the substrate displacement and the actin flow leads to friction coefficient estimates that are in-line with some previously reported results. • Viscous friction couples an active gel, modeling the cell, and an elastic half-space. • We solve the integro-differential problem arising for traveling wave solutions. • Experiments verify the relation between actin velocity and substrate displacement. • A biphasic dependence on friction of steady-state velocity arises from this coupling. • This arises from nonlocal effects and without any nonlinear element in the model. [ABSTRACT FROM AUTHOR]

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Abstract: We report the case of a 26-year-old patient who was victim of severe head trauma following a trafic road accident. Two days after trauma, she had fever, pancytopenia and multi-organ failure. The haemophagocytic lymphohistiocytosis syndrome was suspected. This diagnosis was confirmed by biologic findings (elevated serum levels of ferritin and triglycerid) and histological findings (examination of bone marrow smears showing histiocytes phagocytosing blood cells). The evolution was unfavorable despite of corticotherapy and symptomatic measures. [Copyright &y& Elsevier]

Abstract: We report the case of a patient who was victim of a hydrogen sulphide poisoning. This poisoning took place following a fall in sewers. The initial clinical presentation was dominated by an acute respiratory failure caused by an acute pulmonary oedema. In this context, non cardiogenic pulmonary oedema is usually evoked in the literature. Our observation supports a left ventricular systolic dysfunction as a possible cause of this cardiorespiratory complication. The initial presentation was also marked by a coma which is often associated with severe poisonings by hydrogen sulphide. Evolution was favourable under symptomatic treatment. We discuss the mechanism of heart and neurological failure. [Copyright &y& Elsevier]

Résumé Le syndrome HELLP est l’acronyme de Hemolysis, Elevated Liver enzymes and Low Platelets. Il est généralement considéré dans la littérature comme une forme clinique particulière de la pré-éclampsie, complication sévère de la deuxième moitié de la grossesse. Néanmoins, ce syndrome peut survenir de manière isolée en l’absence de signes de pré-éclampsie. Sa physiopathologie reste encore mal connue. Le tableau clinique est souvent incomplet et fruste au début. À ce jour, son diagnostic et sa prise en charge font encore l’objet de nombreuses controverses. Associé ou non à un contexte vasculo-rénal, le syndrome HELLP est une pathologie à haut risque maternel. L’objectif de ce travail est de faire le point sur les données physiopathologiques, cliniques et thérapeutiques actuelles. HELLP syndrome is an acronym for Hemolysis, Elevated Liver enzymes and Low Platelets. It is generally considered in the literature as a particular clinical form of pre-eclampsia, a severe complication of the second half of pregnancy. However, this syndrome can occur in isolation in the absence of pre-eclampsia symptoms. Its pathophysiology remains still unclear. The clinical picture is often incomplete and fruste at first. To date, its diagnosis and management is still the subject of much controversy. Associated or not with a vascular and renal manifestations, the HELLP syndrome is a high-risk maternal disorder. The objective of this article is to review the pathophysiological and clinical data and current treatment. [ABSTRACT FROM AUTHOR]

Résumé Nous rapportons le cas d’un œdème aigu du poumon (OAP) grave secondaire à l’administration de salbutamol chez une patiente traitée pour asthme aigu grave. Le diagnostic d’OAP a été évoqué devant les données cliniques, radiographiques, biologiques (dosage du Pro-BNP) et échocardiographiques. L’évolution rapidement favorable sous dobutamine et ventilation mécanique est également en faveur de ce diagnostic. Le jeune age de la patiente, l’absence de facteur de risque cardiovasculaire, la chronologie de cette complication par rapport à l’introduction du salbutamol, ainsi que l’absence d’une autre cause évidente pouvant induire une dysfonction ventriculaire gauche pourrait faire évoquer le rôle des β2 mimétiques dans la survenue de cette complication. La normalisation secondaire de la fonction cardiaque à l’échocardiographie et l’absence d’anomalie à la scintigraphie myocardique réalisée 35 jours après montrent la réversibilité de cette dysfonction ventriculaire gauche. We report the case of a severe acute pulmonary edema secondary to the administration of salbutamol to a patient admitted for severe asthma. The diagnosis of acute pulmonary edema was suspected on the clinical examination, chest radiography, biological (plasmatic Pro-BNP rate) and echocardiographic findings. Rapid improvement under dobutamine and mechanical ventilation argue in favour of cardiogenic pulmonary edema. The young age of our patient, the absence of history of cardiovascular disease and the chronology of this complication onset regarded to salbutamol infusion could suggest β2 agonist involvement in this event. The improvement of cardiac function on echocardiography and the normal results obtained with myocardial perfusion scintigraphy performed 35 days later show the left ventricular reversible dysfunction. [ABSTRACT FROM AUTHOR]

Abstract: Introduction: Peripartum cardiomyopathy (PPCM) is a rare and life-threatening disease of unknown aetiology. The primary objective of this review was to analysed aetiopathogeneses, clinical presentation and diagnosis, as well as pharmacological, perioperative and intensive care management and prognosis of this pathology. Methods: We undertook a systematic review of the literature using Medline, Google Scholar and PubMed searches. Results: Unlike other parts of the world in which cardiomyopathy are rare, dilated cardiomyopathy is a major cause of heart failure throughout Africa. Its aetiopathogenesis is still poorly understood, but recent evidence supports inflammation, viral infection and autoimmunity as the leading causative hypotheses. This diagnosis should be limited to previously healthy women who present with congestive heart failure (CHF) and decreased left ventricular systolic function in the last month of pregnancy or within 5 months after delivery. Recently, introduction of echocardiography has made diagnosis of PPCM easier and more accurate. Conventional treatment consists of diuretics, vasodilators, and sometimes digoxin and anticoagulants, usually in combination. Patients who fail to recover may require inotropic therapy. In resistant cases, newer therapeutic modalities such as immunomodulation, immunoglobulin and immunosuppression may be considered. Prognosis is highly related to reversal of ventricular dysfunction. Compared to historically higher mortality rates, recent reports describe better outcome, probably because of advances in medical care. Based on current information, future pregnancy is usually not recommended in patients who fail to recover normal heart function. Conclusion: PPCM is a rare but serious form of cardiac failure affecting women in the last months of pregnancy or early puerperium. Its aetiopathogenesis is still poorly understood. Introduction of echocardiography has made diagnosis of PPCM easier and more accurate. Prognosis is highly related to reversal of ventricular dysfunction. [Copyright &y& Elsevier]

Abstract: Objectives: To analyze the clinico-biological manifestations, identify the causes and evaluate the outcome of patients with severe thrombotic microangiopathies admitted in a Tunisian intensive care unit. Methods: Retrospective study over a period of 10 years (1995–2004) in an intensive care unit. Results: Were included in this study 9 cases with a mean age of 29.2±9 years (range 15–44 years). Fever was observed in 5 patients, neurological impairment in 5 and digestive manifestations in 6. Haemolytic anaemia, thrombocytopenia and acute renal failure were observed in 100% of the cases. In our study, the aetiologies of thrombotic microangiopathies were: complicated pregnancy in 6 cases, systemic lupus erythematosus in 1 case. In contrast, no aetiology was found in 2 patients. Plasma exchange was performed in 5 patients, while 4 patients received only plasma infusion. After an average stay of 18±12.5 days, evolution was marked by the death 3 patients. Conclusion: The incidence of severe thrombotic microangiopathies is rare in Tunisian ICU. The clinical manifestations are not specific. Despite the improvement in the outcome by exogenous plasma supply, thrombotic microangiopathies with severe organ dysfunctions leading to hospitalization in the intensive care unit are associated with a high mortality rate. [Copyright &y& Elsevier]

Abstract: Objective: To report the clinical experience, biochemical findings, complications and maternal outcome in patients with acute fatty liver of pregnancy (AFLP). Patients and methods: Retrospective study over a period of 11 years (1993–2003). The diagnosis of AFLP was confirmed by liver biopsy in 15 women. However, in 7 women a medical committee that took into account clinical symptoms, and laboratory findings assessed the diagnosis. Results: Were included in this study, 22 women with a mean age of 30±5.4 years. Only 22.7% of cases were primigravid. The mean gestational age was 36±2.76 weeks (range 31–41 weeks). The fetus was a male infant in 75% of cases. Ten women were admitted in the hospital without jaundice. However 15 women had developed an icterus since their hospital admission or during ICU stay. The mean SAPS II on the ICU admission was of 24.86±11.2 points. Biological disturbances observed were mainly: liver cytolysis in 91% of cases, a trend to hypoglycaemia in 86%, a hypoprotidemia in 66.7% and CIVD in 32%. During their ICU stay, 19 women (86.4%) developed one or several organ failures associated to the hepatic failure and 18 women required blood transfusion. After an average stay of 7.5 days, evolution was marked by the death of seven patients (31.8%). Factors correlated with a poor prognosis were: the delay of medical consultation, the development of jaundice, the development of encephalopathy, respiratory or a circulatory failure. Discussion and conclusion: AFLP is a rare but life-threatening complication. Furthermore AFLP shares features with other more common and less perilous illnesses. An early diagnosis and appropriate therapy of this pathology should improve the poor prognosis in our country. [Copyright &y& Elsevier]

Abstract: Objective. – To determine the frequency of contamination, the sensitivity, specificity, and predictive values of cultures done with blood drawn through a central venous catheter or peripheral venipuncture. Design. – Prospective cohort study of critical ill medical surgical intensive care patients in whom samples for paired culture were drawn through a central venous catheter or peripheral venipuncture during a period of 8 months (from August 1st 2001 to Mars 31st 2002). Results. – During the study period, 75-paired cultures were studied. Fifteen peripheral blood cultures (20%) and 27 central blood cultures (36%) were positive and 6 peripheral blood cultures (8%) and 15 central blood cultures (20%) were contaminated (P =0.034). The organism most commonly responsible for contamination was Coagulase Negative Staphylococcus (16% of central blood cultures and 6.7% of peripheral blood cultures). The frequency of contamination was of 42.9% for blood cultures drawn through a femoral central venous catheter, of 10% for jugular, and of 19% for subclavian central venous catheter (P =0.22). For catheter draws compared with peripheral venipuncture, sensitivity was 100 and 75%, specificity was 76.2 and 90.5%, positive predictive value was 44.4 and 60% and negative predictive value was 100 and 95%. Conclusion. – Cultures of blood drawn through a catheter are more sensible and less specific than those obtained from a peripheral venipuncture and the organism most commonly responsible for contamination of blood cultures is Coagulase Negative Staphylococcus. [Copyright &y& Elsevier]

Abstract: Objective. – To evaluate the predictive value of pericatheter skin cultures in detecting catheter-related infections in critically-ill patients. Study design. – Prospective study. Patients and methods. – Over a 5 months period (from August 1st 2001 to December 31 2001), 500 patients were hospitalised, and 108 central venous catheters were prospectively examined. For each catheter, blood cultures, pericatheter skin cultures and semiquantitative culture of the catheter tip were performed. Results. – The median duration of catheterization was 8 days (interquartile: 8 days). Catheter was removed because of suspected infection in 54 cases (50%). Systemic catheter-related infection was found in 12 cases (11%) and the responsible organism was a gram-negative rod in 11 cases (92%). The negative predictive values of pericatheter skin cultures in the diagnosis of catheter-related infections and in case of suspected catheter-related infection were 89 and 86%, respectively. Conclusion. – These results indicate that the pericatheter skin cultures are not an effective procedure for the conservative diagnosis of catheter-related infections and that the skin-insertion wound is not the major source of catheter-contamination in our unit. [Copyright &y& Elsevier]

Résumé: Le kyste hydatique du foie (KHF) est une maladie assez répandue dans les pays nord-africains. Nous rapportons l’observation d’un patient de 39ans admis au service de réanimation médicale pour état de choc anaphylactique rattaché à un KHF fissuré de découverte fortuite. Cette fissuration a été également compliquée par la survenue d’un accident vasculaire cérébral (AVC) ischémique dont les mécanismes sont discutés. [ABSTRACT FROM AUTHOR]