Functional analysis: evaluation of response intensities--tailoring ANOVA for lists of expression subsets.

Background: Microarray data is frequently used to characterize the expression profile of a whole genome and to compare the characteristics of that genome under several conditions. Geneset analysis methods have been described previously to analyze the expression values of several genes related by known biological criteria (metabolic pathway, pathology signature, co-regulation by a common factor, etc.) at the same time and the cost of these methods allows for the use of more values to help discover the underlying biological mechanisms. Results: As several methods assume different null hypotheses, we propose to reformulate the main question that biologists seek to answer. To determine which genesets are associated with expression values that differ between two experiments, we focused on three ad hoc criteria: expression levels, the direction of individual gene expression changes (up or down regulation), and correlations between genes. We introduce the FAERI methodology, tailored from a two-way ANOVA to examine these criteria. The significance of the results was evaluated according to the self-contained null hypothesis, using label sampling or by inferring the null distribution from normally distributed random data. Evaluations performed on simulated data revealed that FAERI outperforms currently available methods for each type of set tested. We then applied the FAERI method to analyze three real-world datasets on hypoxia response. FAERI was able to detect more genesets than other methodologies, and the genesets selected were coherent with current knowledge of cellular response to hypoxia. Moreover, the genesets selected by FAERI were confirmed when the analysis was repeated on two additional related datasets. Conclusions: The expression values of genesets are associated with several biological effects. The underlying mathematical structure of the genesets allows for analysis of data from several genes at the same time. Focusing on expression levels, the direction of the expression changes, and correlations, we showed that two-step data reduction allowed us to significantly improve the performance of geneset analysis using a modified two-way ANOVA procedure, and to detect genesets that current methods fail to detect.

Predictors of awakening from postanoxic status epilepticus after therapeutic hypothermia.

BACKGROUND: Postanoxic status epilepticus (PSE) is considered a predictor of fatal outcome and therefore not intensively treated; however, some patients have had favorable outcomes. The aim of this study was to identify favorable predictors for awakening beyond vegetative state in PSE. METHODS: We studied six subjects treated with hypothermia improving beyond vegetative state after cerebral anoxia, despite PSE. They were among a cohort of patients treated for anoxic encephalopathy with therapeutic hypothermia in our institution between October 1999 and May 2006 (retrospectively, 3/107 patients) and June 2006 and May 2008 (prospectively, 3/74 patients). PSE was defined by clinical and EEG criteria. Outcome was assessed according to the Glasgow-Pittsburgh Cerebral Performance Categories (CPC). RESULTS: All improving patients had preserved brainstem reflexes, cortical somatosensory evoked potentials, and reactive EEG background during PSE. Half of them had myoclonic PSE, while three had nonconvulsive PSE. In the prospective arm, 3/28 patients with PSE showed this clinical-electrophysiologic profile; all awoke. Treatments consisted of benzodiazepines, various antiepileptic drugs, and propofol. One subject died of pneumonia in a minimally conscious state, one patient returned to baseline (CPC1), three had moderate impairment (CPC2), and one remained dependent (CPC3). Patients with nonconvulsive PSE showed a better prognosis than subjects with myoclonic PSE (p = 0.042). CONCLUSION: Patients with postanoxic status epilepticus and preserved brainstem reactions, somatosensory evoked potentials, and EEG reactivity may have a favorable outcome if their condition is treated as status epilepticus.

Prise en charge du syndrome post-thrombotique [Management of post-thrombotic syndrome].

Post-thrombotic syndrome (PTS) is the most frequent chronic complication of deep vein thrombosis with an estimated prevalence of 30-50%. PTS is a significant cause of disability, especially when complicated by venous ulcers. Therefore, it has important socio-economic consequences for both the patient and the health care system. Aim of this review is to resume state of the art literature on the management of PTS.

Speech and oromotor deficits of epileptic origin in benign partial epilepsy of childhood with rolandic spikes (BPERS). Relationship to the acquired aphasia-epilepsy syndrome.

The authors report three children who suffered temporary oromotor or speech disturbances as focal epileptic manifestations within the frame of benign partial epilepsy of childhood with rolandic spikes and review similar cases described in the literature. The deficit can occur as an initial symptom of the disorder without visible epileptic seizures and interferes in a variable way with simple voluntary oromotor functions or complex movements including speech production, depending on the exact location and spread of the discharging epileptic focus around the perisylvian region. The most severe deficit produces the anterior operculum syndrome. More subtle non-linguistic deficits such as intermittent drooling, oromotor apraxia or dysfluency, as well as linguistic ones involving phonologic production, can occur. The rapidity of onset, progression and recovery of the deficit is very variable as well as its duration and presumably reflects the degree of epileptic activity. In some cases, rapid improvement with antiepileptic medication occurs and coincidence between the paroxysmal EEG activity (which is usually bilateral) and the functional deficit is seen. The clinical and EEG profile of the seizures disorder and the dynamic of the deficit in these cases bear a strong resemblance to what is seen in the acquired epilepsy-aphasia syndrome (Landau and Kleffner). The variations in clinical symptoms appear more related to the main site, local extension and bilaterality of the epileptic foci rather than a basic difference in physiopathology.

Hypoxic Pulmonary Hypertension, Novel Predisposing Factors, Unsuspected Mechanisms

High altitude constitutes an exciting natural laboratory for medical research. Over the past decade, high-altitude studies have provided important new insight into the regulation of the pulmonary circulation. Studies in high-altitude pulmonary edema (HAPE)-prone subjects, a condition characterized by exaggerated hypoxic pulmonary hypertension, have provided evidence for the central role of pulmonary vascular endothelial and respiratory epithelial nitric oxide for pulmonary artery pressure homeostasis. Studies of healthy and maladapted high-altitude dwellers have provide important new insight into mechanisms conferring protection against/predisposing to pulmonary hypertension. Finally, the ambient hypoxia associated with high-altitude exposure facilitates the detection of pulmonary (and systemic) vascular dysfunction at an early stage. Here, we will summarize recent studies that, by capitalizing on these observations, have led to the description of novel mechanisms underpinning pulmonary hypertension and to the first direct demonstration of fetal programming of pulmonary vascular dysfunction in humans.

Pacing redistributes glycogen within the developing myocardium.

Electrical pacing at physiological rate induces myocardial remodeling associated with regional changes in workload, blood flow and oxygen consumption. However, to what extent energy-producing pathways are also modified within the paced heart remains to be investigated. Pacing could particularly affect glycogen metabolism since hypertrophy stimulates glycolysis and increased workload favors glucose over fat oxidation. In order to test this hypothesis, we used the embryonic chick heart model in which ventricular pacing rapidly resulted in thinning of the ventricle wall and thickening of the atrial wall. Hearts of stage 22HH chick embryos were submitted in ovo to asynchronous and intermittent ventricular pacing delivered at physiological rate during 24 h. The resulting alterations of glycogen content were determined in atrium, ventricle and conotruncus of paced and sham-operated hearts. Hemodynamic parameters of the paced and spontaneously beating hearts were derived from computerized image analysis of video recordings. With respect to sham, paced hearts showed a significant decrease in glycogen content (nmoles glucose units/microg protein; mean+/-S.D.) only in atrium (1.48+/-0.40 v 0.84+/-0.34, n=8) and conotruncus (0.75+/-0.28 v 0.42+/-0.23, n=8). Pacing decreased the end diastolic and stroke volumes by 34 and 44%, respectively. Thus, the rapid glycogen depletion in regions remote from the stimulation site appears to be associated with regional changes in workload and remodeling. These findings underscore the importance of the coupling mechanisms between metabolic pathways and myocardial remodeling in the ectopically paced heart.

Vascular dysfunction in children conceived by assisted reproductive technologies: underlying mechanisms and future implications.

Epidemiological studies in humans have demonstrated a relationship between pathological events during fetal development and increased cardiovascular risk later in life and have led to the so called "Fetal programming of cardiovascular disease hypothesis". The recent observation of generalised vascular dysfunction in young apparently healthy children conceived by assisted reproductive technologies (ART) provides a novel and potentially very important example of this hypothesis. This review summarises recent data in ART children demonstrating premature subclinical atherosclerosis in the systemic circulation and pulmonary vascular dysfunction predisposing to exaggerated hypoxia-induced pulmonary hypertension. These problems appear to be related to the ART procedure per se. Studies in ART mice demonstrating premature vascular aging and arterial hypertension further demonstrate the potential of ART to increase cardiovascular risk and have allowed to unravel epigenetic alterations of the eNOS gene as an underpinning mechanism. The roughly 25% shortening of the life span in ART mice challenged with a western style high-fat-diet demonstrates the potential importance of these alterations for the long-term outcome. Given the young age of the ART population, data on cardiovascular endpoints will not be available before 20 to 30 years from now. However, already now cohort studies of the ART population are needed to early detect cardiovascular alterations with the aim to prevent or at least optimally treat cardiovascular complications. Finally, a debate needs to be engaged on the future of ART and the consequences of its exponential growth for public health.

Recommendations on the use of EEG monitoring in critically ill patients: consensus statement from the neurointensive care section of the ESICM.

OBJECTIVES: Recommendations for EEG monitoring in the ICU are lacking. The Neurointensive Care Section of the ESICM assembled a multidisciplinary group to establish consensus recommendations on the use of EEG in the ICU. METHODS: A systematic review was performed and 42 studies were included. Data were extracted using the PICO approach, including: (a) population, i.e. ICU patients with at least one of the following: traumatic brain injury, subarachnoid hemorrhage, intracerebral hemorrhage, stroke, coma after cardiac arrest, septic and metabolic encephalopathy, encephalitis, and status epilepticus; (b) intervention, i.e. EEG monitoring of at least 30 min duration; (c) control, i.e. intermittent vs. continuous EEG, as no studies compared patients with a specific clinical condition, with and without EEG monitoring; (d) outcome endpoints, i.e. seizure detection, ischemia detection, and prognostication. After selection, evidence was classified and recommendations developed using the GRADE system. RECOMMENDATIONS: The panel recommends EEG in generalized convulsive status epilepticus and to rule out nonconvulsive seizures in brain-injured patients and in comatose ICU patients without primary brain injury who have unexplained and persistent altered consciousness. We suggest EEG to detect ischemia in comatose patients with subarachnoid hemorrhage and to improve prognostication of coma after cardiac arrest. We recommend continuous over intermittent EEG for refractory status epilepticus and suggest it for patients with status epilepticus and suspected ongoing seizures and for comatose patients with unexplained and persistent altered consciousness. CONCLUSIONS: EEG monitoring is an important diagnostic tool for specific indications. Further data are necessary to understand its potential for ischemia assessment and coma prognostication.

Selective neurodegeneration induced in rotation-mediated aggregate cell cultures by a transient switch to stationary culture conditions: a potential model to study ischemia-related pathogenic mechanisms.

Aggregating brain cell cultures at an advanced maturational stage (20-21 days in vitro) were subjected for 1-3 h to anaerobic (hypoxic) and/or stationary (ischemic) conditions. After restoration of the normal culture conditions, cell loss was estimated by measuring the release of lactate dehydrogenase as well as the irreversible decrease of cell type-specific enzyme activities, total protein and DNA content. Ischemia for 2 h induced significant neuronal cell death. Hypoxia combined with ischemia affected both neuronal and glial cells to different degrees (GABAergic neurons>cholinergic neurons>astrocytes). Hypoxic and ischemic conditions greatly stimulated the uptake of 2-deoxy-D-glucose, indicating increased glucose consumption. Furthermore, glucose restriction (5.5 mM instead of 25 mM) dramatically increased the susceptibility of neuronal and glial cells to hypoxic and ischemic conditions. Glucose media concentrations below 2 mM caused selective neuronal cell death in otherwise normal culture conditions. GABAergic neurons showed a particularly high sensitivity to glucose restriction, hypoxia, and ischemia. The pattern of ischemia-induced changes in vitro showed many similarities to in vivo findings, suggesting that aggregating brain cell cultures provide a useful in vitro model to study pathogenic mechanisms related to brain ischemia.

Multiple interacting cell death mechanisms in the mediation of excitotoxicity and ischemic brain damage: A challenge for neuroprotection.

There is currently no approved neuroprotective pharmacotherapy for acute conditions such as stroke and cerebral asphyxia. One of the reasons for this may be the multiplicity of cell death mechanisms, because inhibition of a particular mechanism leaves the brain vulnerable to alternative ones. It is therefore essential to understand the different cell death mechanisms and their interactions. We here review the multiple signaling pathways underlying each of the three main morphological types of cell death - apoptosis, autophagic cell death and necrosis - emphasizing their importance in the neuronal death that occurs during cerebral ischemia and hypoxia-ischemia, and we analyze the interactions between the different mechanisms. Finally, we discuss the implications of the multiplicity of cell death mechanisms for the design of neuroprotective strategies.

Postoperative management of adult central neurosurgical patients: systemic and neuro-monitoring.

Postoperative neurosurgical patients are at risk of developing complications. Systemic and neuro-monitoring are used to identify patients who deteriorate in order to treat the underlying cause and minimize the impact on outcome. Hypotension and hypoxia are likely to be the most frequent insults and can be detected easily with blood pressure monitoring and pulse oximetry. Repeated clinical examination, however, is probably the most important monitor in the postoperative setting. Clinical scores such as the Glasgow Coma Score and the more recently introduced FOUR Score are important tools to standardize the clinical assessment. Intracranial pressure monitoring, cerebral blood flow monitoring, electroencephalography, and brain imaging are often used postoperatively. Despite the numerous publications on this topic only few studies address the impact of postoperative monitoring on outcome. Accordingly, in most patients the decision on which monitors are to be used must be based on the patient's presentation and clinical judgment.

BAL9141, a novel extended-spectrum cephalosporin active against methicillin-resistant Staphylococcus aureus in treatment of experimental endocarditis.

The therapeutic efficacy of BAL9141 (formerly Ro 63-9141), a novel cephalosporin with broad in vitro activity that also has activity against methicillin-resistant Staphylococcus aureus (MRSA), was investigated in rats with experimental endocarditis. The test organisms were homogeneously methicillin-resistant S. aureus strain COL transformed with the penicillinase-encoding plasmid pI524 (COL Bla+) and homogeneously methicillin-resistant, penicillinase-producing isolate P8-Hom, selected by serial exposure of parent strain P8 to methicillin. The MICs of BAL9141 for these organisms (2 mg/liter) were low, and BAL9141was bactericidal in time-kill curve studies after 24 h of exposure to either two, four, or eight times the MIC. Rats with experimental endocarditis were treated in a three-arm study with a continuous infusion of BAL5788 (formerly Ro 65-5788), a carbamate prodrug of BAL9141, or with amoxicillin-clavulanate or vancomycin. The rats were administered BAL9141 to obtain steady-state target levels of 20, 10, and 5 mg of per liter or were administered either 1.2 g of amoxicillin-clavulanate (ratio 5:1) every 6 h or 1 g of vancomycin every 12 h at changing flow rates to simulate the pharmacokinetics produced in humans by intermittent intravenous treatment. Treatment was started 12 h after bacterial challenge and lasted for 3 days. BAL9141 was successful in the treatment of experimental endocarditis due to either MRSA isolate COL Bla+ or MRSA isolate P8-Hom at the three targeted steady-state concentrations and sterilized >90% of cardiac vegetations (P < 0.005 versus controls; P < 0.05 versus amoxicillin-clavulanate and vancomycin treatment groups). These promising in vivo results with BAL9141 correlated with the high affinity of the drug for PBP 2a and its stability to penicillinase hydrolysis observed in vitro.

Early Cretaceous radiolarians of the Northeast Indian Ocean (leg 123 - site 765, site 766 and dsdp site 261) - The Antarctic-Tethys connection

During ODP Leg 123, abundant and well-preserved Neocomian radiolarians were recovered at Site 765 (Argo Abyssal Plain) and Site 766 (lower Exmouth Plateau). Assemblages are characterized by the numerical dominance of a small number of non-tethyan forms and by the scarcity of tethyan taxa. Remarkable contrasts exist between radiolarian assemblages extracted from claystones of Site 765 and reexamined DSDP Site 26 1, and faunas recovered from radiolarian sand layers, only found at Site 765. Clay faunas are unusual in their low diversity of apparently ecologically tolerant (or solution resistant?), ubiquist species, whereas sand faunas are dominated by non-tethyan taxa. Comparisons with Sites 766 and 26 1, as well as sedimentological observations, lead to the conclusion that this faunal contrast resulted from a difference in provenance, rather than from hydraulic sorting or selective dissolution. The ranges of 27 tethyan taxa from Site 765 were compared to the tethyan radiolarian zonation by Jud (1992) by means of the Unitary Associations Method. This calculation allows to directly date the Site 765 assemblages and to estimate the amount of truncation of ranges for tethyan taxa. Over 70% of the already few tethyan species of Site 765, have truncated ranges during the Valanginian-Hauterivian. Radiolarian assemblages recovered from claystones at Sites 765 and 261 in the Argo Basin apparently reflect restricted oceanic conditions during the latest Jurassic-Barremian. Neither sedimentary facies nor faunal associations bear any resemblance to what we know from typical tethyan sequences. We conclude that the Argo Basin was paleoceanographically separated from the Tethys during the Late Jurassic and part of the Early Cretaceous by its position at higher paleolatitudes and/or by enclosing land masses. Assemblages recovered from radiolarian sand layers are dominated by non-tethyan species that are interpreted as circumantarctic. Their first appearance in the late Berriasian-early Valanginian predates the oceanization of the Indo-Australian breakup (M11, late Valanginian), but coincides with a sharp increase in margin-derived pelagic turbidites. The Indo-Australian rift zone and the adjacent margins must have been submerged deeply enough to allow an intermittent influx of circumantarctic cold water into the Argo Basin, creating increased bottom current activity. Cold-water radiolarians carried into the Argo Basin upwelled along the margin, died, and accumulated in radiolarite layers due to winnowing by bottom currents. High rates of faunal change and the sharp increase of bottom current activity are thought to be synchronous with possible pronounced late Berriasian-early Valanginian lowstands in sea level. Hypothetically, both phenomena might have been.caused by a tendency to glaciation on the Antarctic-Australian continent, which was for the first time isolated from the rest of Gondwana by oceanic seaways as a result of Jurassic-Early Cretaceous sea-floor spreading. The absence of most typical tethyan radiolarian species during the Valanginian-Hauterivian is interpreted as reflecting a time of strong influx of circumantarctic cold water following oceanization (M11) and rapid spreading between Southeast India and West Australia. The reappearance and gradual abundance/diversity increase of tethyan taxa, along with the still dominant circumantarctic species are thought to result from overall more equitable climatic conditions during the Barremian-early Aptian and from the establishment of an oceanic connection with the Tethys Ocean during the early Aptian.

Chest wall syndrome among primary care patients: a cohort study.

BACKGROUND: The epidemiology of chest pain differs strongly between outpatient and emergency settings. In general practice, the most frequent cause is the chest wall pain. However, there is a lack of information about the characteristics of this syndrome. The aims of the study are to describe the clinical aspects of chest wall syndrome (CWS). METHODS: Prospective, observational, cohort study of patients attending 58 private practices over a five-week period from March to May 2001 with undifferentiated chest pain. During a one-year follow-up, questionnaires including detailed history and physical exam, were filled out at initial consultation, 3 and 12 months. The outcomes were: clinical characteristics associated with the CWS diagnosis and clinical evolution of the syndrome. RESULTS: Among 24 620 consultations, we observed 672 cases of chest pain and 300 (44.6%) patients had a diagnosis of chest wall syndrome. It affected all ages with a sex ratio of 1:1. History and sensibility to palpation were the keys for diagnosis. Pain was generally moderate, well localised, continuous or intermittent over a number of hours to days or weeks, and amplified by position or movement. The pain however, may be acute. Eighty-eight patients were affected at several painful sites, and 210 patients at a single site, most frequently in the midline or a left-sided site. Pain was a cause of anxiety and cardiac concern, especially when acute. CWS coexisted with coronary disease in 19 and neoplasm in 6. Outcome at one year was favourable even though CWS recurred in half of patients. CONCLUSION: CWS is common and benign, but leads to anxiety and recurred frequently. Because the majority of chest wall pain is left-sided, the possibility of coexistence with coronary disease needs careful consideration.

Dietary obesity-associated Hif1α activation in adipocytes restricts fatty acid oxidation and energy expenditure via suppression of the Sirt2-NAD+ system.

Dietary obesity is a major factor in the development of type 2 diabetes and is associated with intra-adipose tissue hypoxia and activation of hypoxia-inducible factor 1α (HIF1α). Here we report that, in mice, Hif1α activation in visceral white adipocytes is critical to maintain dietary obesity and associated pathologies, including glucose intolerance, insulin resistance, and cardiomyopathy. This function of Hif1α is linked to its capacity to suppress β-oxidation, in part, through transcriptional repression of sirtuin 2 (Sirt2) NAD(+)-dependent deacetylase. Reduced Sirt2 function directly translates into diminished deacetylation of PPARγ coactivator 1α (Pgc1α) and expression of β-oxidation and mitochondrial genes. Importantly, visceral adipose tissue from human obese subjects is characterized by high levels of HIF1α and low levels of SIRT2. Thus, by negatively regulating the Sirt2-Pgc1α regulatory axis, Hif1α negates adipocyte-intrinsic pathways of fatty acid catabolism, thereby creating a metabolic state supporting the development of obesity.