Conflict, Competition, and Cooperation Regulate Social Interactions in Filamentous Fungi.

Social cooperation impacts the development and survival of species. In higher taxa, kin recognition occurs via visual, chemical, or tactile cues that dictate cooperative versus competitive interactions. In microbes, the outcome of cooperative versus competitive interactions is conferred by identity at allorecognition loci, so-called kind recognition. In syncytial filamentous fungi, the acquisition of multicellularity is associated with somatic cell fusion within and between colonies. However, such intraspecific cooperation entails risks, as fusion can transmit deleterious genotypes or infectious components that reduce fitness, or give rise to cheaters that can exploit communal goods without contributing to their production. Allorecognition mechanisms in syncytial fungi regulate somatic cell fusion by operating precontact during chemotropic interactions, during cell adherence, and postfusion by triggering programmed cell death reactions. Alleles at fungal allorecognition loci are highly polymorphic, fall into distinct haplogroups, and show evolutionary signatures of balancing selection, similar to allorecognition loci across the tree of life.

Many ways, one microorganism: Several approaches to study Malassezia in interactions with model hosts.

Malassezia, a lipophilic and lipid-dependent yeast, is a microorganism of current interest to mycobiologists because of its role as a commensal or pathogen in health conditions such as dermatological diseases, fungemia, and, as discovered recently, cancer and certain neurological disorders. Various novel approaches in the study of Malassezia have led to increased knowledge of the cellular and molecular mechanisms of this yeast. However, additional efforts are needed for more comprehensive understanding of the behavior of Malassezia in interactions with the host. This article reviews advances useful in the experimental field for Malassezia.

Fusarium and Neocosmospora: fungal priority pathogens in laboratory diagnosis.

Fusarium and Neocosmospora are two fungal genera recently recognized in the list of fungal priority pathogens. They cause a wide range of diseases that affect humans, animals, and plants. In clinical laboratories, there is increasing concern about diagnosis due to limitations in sample collection and morphological identification. Despite the advances in molecular diagnosis, due to the cost, some countries cannot implement these methodologies. However, recent changes in taxonomy and intrinsic resistance to antifungals reveal the necessity of accurate species-level identification. In this review, we discuss the current phenotypic and molecular tools available for diagnosis in clinical laboratory settings and their advantages and disadvantages.

Confining CO2 inside sI clathrate-hydrates: The impact of the CO2 -water interaction on quantized dynamics.

We report new results on the translational-rotational (T-R) states of the CO2 molecule inside the sI clathrate-hydrate cages. We adopted the multiconfiguration time-dependent Hartree methodology to solve the nuclear molecular Hamiltonian, and to address issues on the T-R couplings. Motivated by experimental X-ray observations on the CO2 orientation in the D and T sI cages, we aim to evaluate the effect of the CO2 -water interaction on quantum dynamics. Thus, we first compared semiempirical and ab initio-based pair interaction model potentials against first-principles DFT-D calculations for ascertaining the importance of nonadditive many-body effects on such guest-host interactions. Our results reveal that the rotational and translational excited states quantum dynamics is remarkably different, with the pattern and density of states clearly affected by the underlying potential model. By analyzing the corresponding the probability density distributions of the calculated T-R eigenstates on both semiempirical and ab initio pair CO2 -water nanocage potentials, we have extracted information on the altered CO2 guest local structure, and we discussed it in connection with experimental data on the orientation of the CO2 molecule in the D and T sI clathrate cages available from neutron diffraction and 13 C solid-state NMR studies, as well as in comparison with previous molecular dynamics simulations. Our calculations provide a very sensitive test of the potential quality by predicting the low-lying T-R states and corresponding transitions for the encapsulated CO2 molecule. As such spectroscopic observables have not been measured so far, our results could trigger further detailed experimental and theoretical investigations leading to a quantitative description of the present guest-host interactions.

Changes in patterns of alcohol consumption in young psychiatric outpatients: two comparable samples assessed with 10 years apart.

AIMS: Over the past 20 years, a trend towards non-drinking and less use of alcohol has been reported among young adults. This study aimed to investigate if a similar trend in alcohol consumption can be seen among young adult psychiatric outpatients. METHODS: This was a cross-sectional study based on two comparable samples of young adult (18-25 years) psychiatric outpatients recruited approximately 10 years apart in 2002-2003 (N = 197) and 2012-2016 (N = 380). The Swedish version of the Alcohol Use Disorders Identification Test (AUDIT) was used to assess alcohol consumption. Psychiatric diagnoses were based on diagnostic interviews. Differences between the two samples in alcohol consumption and a number of alcohol-use disorder diagnoses were analysed. Cramer's V was chosen as the effect size measure. RESULTS: Mean AUDIT scores and prevalence of diagnosed alcohol-use disorder in the two samples did not differ significantly. The number of non-drinkers was larger among patients in the mid-2010s (15.8% vs. 8.1%; χ2 = 6.76, p < 0.01, Φ = 0.11), but when non-drinkers were excluded, the alcohol consumption was higher among females in the later sample. CONCLUSION: The mean level of alcohol consumption seems not to have changed to the same extent among young psychiatric patients as in the general population. However, some young psychiatric patients have followed the trend of non-drinking, while others consume more alcohol. Further studies on both non-drinking and high alcohol consumption in psychiatric patients are needed to understand their mechanisms.

Why Do These Yeasts Smell So Good? Volatile Organic Compounds (VOCs) Produced by Malassezia Species in the Exponential and Stationary Growth Phases.

Malassezia synthesizes and releases volatile organic compounds (VOCs), small molecules that allow them to carry out interaction processes. These lipid-dependent yeasts belong to the human skin mycobiota and are related to dermatological diseases. However, knowledge about VOC production and its function is lacking. This study aimed to determine the volatile profiles of Malassezia globosa, Malassezia restricta, and Malassezia sympodialis in the exponential and stationary growth phases. The compounds were separated and characterized in each growth phase through headspace solid-phase microextraction (HS-SPME) and gas chromatography-mass spectrometry (GC-MS). We found a total of 54 compounds, 40 annotated. Most of the compounds identified belong to alcohols and polyols, fatty alcohols, alkanes, and unsaturated aliphatic hydrocarbons. Unsupervised and supervised statistical multivariate analyses demonstrated that the volatile profiles of Malassezia differed between species and growth phases, with M. globosa being the species with the highest quantity of VOCs. Some Malassezia volatiles, such as butan-1-ol, 2-methylbutan-1-ol, 3-methylbutan-1-ol, and 2-methylpropan-1-ol, associated with biological interactions were also detected. All three species show at least one unique compound, suggesting a unique metabolism. The ecological functions of the compounds detected in each species and growth phase remain to be studied. They could interact with other microorganisms or be an important clue in understanding the pathogenic role of these yeasts.

Fungal cell death: The beginning of the end.

Death is an important part of an organism's existence and also marks the end of life. On a cellular level, death involves the execution of complex processes, which can be classified into different types depending on their characteristics. Despite their "simple" lifestyle, fungi carry out highly specialized and sophisticated mechanisms to regulate the way their cells die, and the pathways underlying these mechanisms are comparable with those of plants and metazoans. This review focuses on regulated cell death in fungi and discusses the evidence for the occurrence of apoptotic-like, necroptosis-like, pyroptosis-like death, and the role of the NLR proteins in fungal cell death. We also describe recent data on meiotic drive elements involved in "spore killing" and the molecular basis of allorecognition-related cell death during cell fusion of genetically dissimilar cells. Finally, we discuss how fungal regulated cell death can be relevant in developing strategies to avoid resistance and tolerance to antifungal agents.

Delving into guest-free and He-filled sI and sII clathrate hydrates: a first-principles computational study.

The dynamics of the formation of a specific clathrate hydrate as well as its thermodynamic transitions depend on the interactions between the trapped molecules and the host water lattice. The molecular-level understanding of the different underlying processes benefits not only the description of the properties of the system, but also allows the development of multiple technological applications such as gas storage, gas separation, energy transport, etc. In this work we investigate the stability of periodic crystalline structures, such as He@sI and He@sII clathrate hydrates by first-principles computations. We consider such host water networks interacting with a guest He atom using selected density functional theory approaches, in order to explore the effects on the encapsulation of a light atom in the sI/sII crystals, by deriving all energy components (guest-water, water-water, guest-guest). Structural properties and energies were first computed by structural relaxations of the He-filled and empty sI/sII unit cells, yielding lattice and compressibility parameters comparable to experimental and theoretical values available for those hydrates. According to the results obtained, the He enclathration in the sI/sII unit cells is a stabilizing process, and both He@sI and He@sII clathrates, considering single cage occupancy, are predicted to be stable whatever the XDM or D4 dispersion correction applied. Our results further reveal that despite the weak underlying interactions the He encapsulation has a rather notable effect on both lattice parameters and energetics, with the He@sII being the most energetically favorable in accord with recent experimental observations.

Learning about microbial language: possible interactions mediated by microbial volatile organic compounds (VOCs) and relevance to understanding Malassezia spp. metabolism.

BACKGROUND: Microorganisms synthesize and release a large diversity of small molecules like volatile compounds, which allow them to relate and interact with their environment. Volatile organic compounds (VOCs) are carbon-based compounds with low molecular weight and generally, high vapor pressure; because of their nature, they spread easily in the environment. Little is known about the role of VOCs in the interaction processes, and less is known about VOCs produced by Malassezia, a genus of yeasts that belongs to the human skin mycobiota. These yeasts have been associated with several dermatological diseases and currently, they are considered as emerging opportunistic yeasts. Research about secondary metabolites of these yeasts is limited. The pathogenic role and the molecular mechanisms involved in the infection processes of this genus are yet to be clarified. VOCs produced by Malassezia yeasts could play an important function in their metabolism; in addition, they might be involved in either beneficial or pathogenic host-interaction processes. Since these yeasts present differences in their nutritional requirements, like lipids to grow, it is possible that these variations of growth requirements also define differences in the volatile organic compounds produced in Malassezia species. AIM OF REVIEW: We present a mini review about VOCs produced by microorganisms and Malassezia species, and hypothesize about their role in its metabolism, which would reveal clues about host-pathogen interaction. KEY SCIENTIFIC CONCEPTS OF REVIEW: Since living organisms inhabit a similar environment, the interaction processes occur naturally; as a result, a signal and a response from participants of these processes become important in understanding several biological behaviors. The efforts to elucidate how living organisms interact has been studied from several perspectives. An important issue is that VOCs released by the microbiota plays a key role in the setup of relationships between living micro and macro organisms. The challenge is to determine what is the role of these VOCs produced by human microbiota in commensal/pathogenic scenarios, and how these allow understanding the species metabolism. Malassezia is part of the human mycobiota, and it is implicated in commensal and pathogenic processes. It is possible that their VOCs are involved in these behavioral changes, but the knowledge about this remains overlocked. For this reason, VOCs produced by microorganisms and Malassezia spp. and their role in several biological processes are the main topic in this review.

Exploring CO2 @sI Clathrate Hydrates as CO2 Storage Agents by Computational Density Functional Approaches.

The formation of specific clathrate hydrates and their transformation at given thermodynamic conditions depends on the interactions between the guest molecule/s and the host water lattice. Understanding their structural stability is essential to control structure-property relations involved in different technological applications. Thus, the energetic aspects relative to CO2 @sI clathrate hydrate are investigated through the computation of the underlying interactions, dominated by hydrogen bonds and van der Waals forces, from first-principles electronic structure approaches. The stability of the CO2 @sI clathrate is evaluated by combining bottom-up and top-down approaches. Guest-free and CO2 guest-filled aperiodic cages, up to the gradually CO2 occupation of the entire sI periodic unit cells were considered. Saturation, cohesive and binding energies for the systems are determined by employing a variety of density functionals and their performance is assessed. The dispersion corrections on the non-covalent interactions are found to be important in the stabilization of the CO2 @sI energies, with the encapsulation of the CO2 into guest-free/empty cage/lattice being always an energetically favorable process for most of the functionals studied. The PW86PBE functional with XDM or D3(BJ) dispersion corrections predicts a lattice constant in accord to the experimental values available, and simultaneously provides a reliable description for the guest-host interactions in the periodic CO2 @sI crystal, as well as the energetics of its progressive single cage occupancy process. It has been found that the preferential orientation of the single CO2 in the large sI crystal cages has a stabilizing effect on the hydrate, concluding that the CO2 @sI structure is favored either by considering the individual building block cages or the complete sI unit cell crystal. Such benchmark and methodology cross-check studies benefit new data-driven model research by providing high-quality training information, with new insights that indicate the underlying factors governing their structure-driven stability, and triggering further investigations for controlling the stabilization of these promising long-term CO2 storage materials.

Computational density-functional approaches on finite-size and guest-lattice effects in CO2@sII clathrate hydrate.

We performed first-principles computations to investigate guest-host/host-host effects on the encapsulation of the CO2 molecule in sII clathrate hydrates from finite-size clusters up to periodic 3D crystal lattice systems. Structural and energetic properties were first computed for the individual and first-neighbors clathrate-like sII cages, where highly accurate ab initio quantum chemical methods are available nowadays, allowing in this way the assessment of the density functional (DFT) theoretical approaches employed. The performance of exchange-correlation functionals together with recently developed dispersion-corrected schemes was evaluated in describing interactions in both short-range and long-range regions of the potential. On this basis, structural relaxations of the CO2-filled and empty sII unit cells yield lattice and compressibility parameters comparable to experimental and previous theoretical values available for sII hydrates. According to these data, the CO2 enclathration in the sII clathrate cages is a stabilizing process, either by considering both guest-host and host-host interactions in the complete unit cell or only the guest-water energies for the individual clathrate-like sII cages. CO2@sII clathrates are predicted to be stable whatever the dispersion correction applied and in the case of single cage occupancy are found to be more stable than the CO2@sI structures. Our results reveal that DFT approaches could provide a good reasonable description of the underlying interactions, enabling the investigation of formation and transformation processes as a function of temperature and pressure.

Microfluidic Platform for the Isolation of Cancer-Cell Subpopulations Based on Single-Cell Glycolysis.

High rates of glycolysis in tumors have been associated with cancer metastasis, tumor recurrence, and poor outcomes. In this light, single cells that exhibit high glycolysis are specific targets for therapy. However, the study of these cells requires efficient tools for their isolation. We use a droplet microfluidic technique developed in our lab, Sorting by Interfacial Tension (SIFT), to isolate cancer cell subpopulations based on glycolysis without the use of labels or active sorting components. By controlling the flow conditions on chip, the threshold of selection can be modified, enabling the isolation of cells with different levels of glycolysis. Hypoxia in tumors, that can be simulated with treatment with CoCl2, leads to an increase in glycolysis, and more dangerous tumors. The device was used to enrich CoCl2 treated MDA-MB 231 breast cancer cells from an untreated population. It is also used to sort K562 human chronic myelogenous leukemia cells that have either been treated or untreated with 2-deoxy-d-glucose (2DG), a pharmaceutical that targets cell metabolism. The technique provides a facile and robust way of separating cells based on elevated glycolytic activity; a biomarker associated with cancer cell malignancy.

Structural Stability of the CO2 @sI Hydrate: a Bottom-Up Quantum Chemistry Approach on the Guest-Cage and Inter-Cage Interactions.

Through reliable first-principles computations, we have demonstrated the impact of CO2 molecules enclathration on the stability of sI clathrate hydrates. Given the delicate balance between the interaction energy components (van der Waals, hydrogen bonds) present on such systems, we follow a systematic bottom-up approach starting from the individual 512 and 512 62 sI cages, up to all existing combinations of two-adjacent sI crystal cages to evaluate how such clathrate-like models perform on the evaluation of the guest-host and first-neighbors inter-cage effects, respectively. Interaction and binding energies of the CO2 occupation of the sI cages were computed using DF-MP2 and different DFT/DFT-D electronic structure methodologies. The performance of selected DFT functionals, together with various semi-classical dispersion corrections schemes, were validated by comparison with reference ab initio DF-MP2 data, as well as experimental data from x-ray and neutron diffraction studies available. Our investigation confirms that the inclusion of the CO2 in the cage/s is an energetically favorable process, with the CO2 molecule preferring to occupy the large 512 62 sI cages compared to the 512 ones. Further, the present results conclude on the rigidity of the water cages arrangements, showing the importance of the inter-cage couplings in the cluster models under study. In particular, the guest-cage interaction is the key factor for the preferential orientation of the captured CO2 molecules in the sI cages, while the inter-cage interactions seems to cause minor distortions with the CO2 guest neighbors interactions do not extending beyond the large 512 62 sI cages. Such findings on these clathrate-like model systems are in accord with experimental observations, drawing a direct relevance to the structural stability of CO2 @sI clathrates.

General Thoracic Surgery in Rwanda: An Assessment of Surgical Volume and of Workforce and Material Resource Deficits.

BACKGROUND: Benchmarking operative volume and resources is necessary to understand current efforts addressing thoracic surgical need. Our objective was to examine the impact on thoracic surgery volume and patient access in Rwanda following a comprehensive capacity building program, the Human Resources for Health (HRH) Program, and thoracic simulation training. METHODS: A retrospective cohort study was conducted of operating room registries between 2011 and 2016 at three Rwandan referral centers: University Teaching Hospital of Kigali, University Teaching Hospital of Butare, and King Faisal Hospital. A facility-based needs assessment of essential surgical and thoracic resources was performed concurrently using modified World Health Organization forms. Baseline patient characteristics at each site were compared using a Pearson Chi-squared test or Kruskal-Wallis test. Comparisons of operative volume were performed using paired parametric statistical methods. RESULTS: Of 14,130 observed general surgery procedures, 248 (1.76%) major thoracic cases were identified. The most common indications were infection (45.9%), anatomic abnormalities (34.4%), masses (13.7%), and trauma (6%). The proportion of thoracic cases did not increase during the HRH program (2.07 vs 1.78%, respectively, p = 0.22) or following thoracic simulation training (1.95 2013 vs 1.44% 2015; p = 0.15). Both university hospitals suffer from inadequate thoracic surgery supplies and essential anesthetic equipment. The private hospital performed the highest percentage of major thoracic procedures consistent with greater workforce and thoracic-specific material resources (0.89% CHUK, 0.67% CHUB, and 5.42% KFH; p < 0.01). CONCLUSIONS AND RELEVANCE: Lack of specialist providers and material resources limits thoracic surgical volume in Rwanda despite current interventions. A targeted approach addressing barriers described is necessary for sustainable progress in thoracic surgical care.

Long-term stability of personality traits in a clinical psychiatric sample.

Background: The aim of this study was to describe personality traits in psychiatric patients and to investigate whether these traits are stable over 13 years. Methods: A total of 95 individuals who were patients at a psychiatric outpatients' clinic in 2003 completed the Swedish universities Scales of Personality (SSP). Scores from 2003 were compared with SSP scores from 2016. Based on the current score on the comprehensive psychopathological rating scale - self rating for affective disorders (CPRS-S-A), the participants were divided into two groups representing 'good' and 'poor' current mental states, to investigate the effect of current mental state on reports of personality traits. Results: Out of 13 personality traits, 11 showed a significant change in mean T-score over the study interval. The group with lower CPRS-S-A scores showed a significant change in T-score for 10 traits, whereas in the group with higher CPRS-S-A scores only 3 traits showed a significant change. Conclusions: The findings support the theory that personality is changeable over the course of life, also in psychiatric patients. We do not know if persisting psychiatric symptoms halter change or if deviant personality traits cause psychiatric symptoms to continue.

Imaging the secretory compartments involved in the intracellular traffic of CHS-4, a class IV chitin synthase, in Neurospora crassa.

In Neurospora crassa hyphae the localization of all seven chitin synthases (CHSs) at the Spitzenkörper (SPK) and at developing septa has been well analyzed. Hitherto, the mechanisms of CHSs traffic and sorting from synthesis to delivery sites remain largely unexplored. In Saccharomyces cerevisiae exit of Chs3p from the endoplasmic reticulum (ER) requires chaperone Chs7p. Here, we analyzed the role of CSE-7, N. crassa Chs7p orthologue, in the biogenesis of CHS-4 (orthologue of Chs3p). In a N. crassa Δcse-7 mutant, CHS-4-GFP no longer accumulated at the SPK and septa. Instead, fluorescence was retained in hyphal subapical regions in an extensive network of elongated cisternae (NEC) referred to previously as tubular vacuoles. In a complemented strain expressing a copy of cse-7 the localization of CHS-4-GFP at the SPK and septa was restored, providing evidence that CSE-7 is necessary for the localization of CHS-4 at hyphal tips and septa. CSE-7 was revealed at delimited regions of the ER at the immediacies of nuclei, at the NEC, and remarkably also at septa and the SPK. The organization of the NEC was dependent on the cytoskeleton. SEC-63, an extensively used ER marker, and NCA-1, a SERCA-type ATPase previously localized at the nuclear envelope, were used as markers to discern the nature of the membranes containing CSE-7. Both SEC-63 and NCA-1 were found at the nuclear envelope, but also at regions of the NEC. However, at the NEC only NCA-1 co-localized extensively with CSE-7. Observations by transmission electron microscopy revealed abundant rough ER sheets and distinct electron translucent smooth flattened cisternae, which could correspond collectively to the NEC, thorough the subapical cytoplasm. This study identifies CSE-7 as the putative ER receptor for its cognate cargo, the polytopic membrane protein CHS-4, and elucidates the complexity of the ER system in filamentous fungi.

Preoperative Gastroesophageal Reflux Disorder Is Associated With Increased Morbidity in Patients Undergoing Abdominal Surgery.

BACKGROUND: In North America, the prevalence of gastroesophageal reflux disorder ranges from 18.1% to 27.8%. We measured the risk posed by preoperative esophageal disease for patients undergoing abdominal operations. METHOD: American College of Surgeons National Surgical Quality Improvement Program (ACS NSQIP; 2005-2015) data were merged with institutional clinical data repository records to identify esophageal disease in surgical patients undergoing intra-abdominal procedures. Patients with esophageal disease were classified as gastroesophageal reflux disorder (GERD) or other, which included patients with esophageal stricture, spasm, ulcer, or diverticuli, achalasia, esophagitis, reflux esophagitis, Barrett's esophagus, and multiple esophageal diagnoses, excluding GERD. ACS NSQIP-targeted procedure groups included were colectomy, proctectomy, ventral hernia repair, bariatric surgery, hepatectomy, appendectomy, abdominal aortic aneurysm repair, open aortoiliac repair, hysterectomy, myomectomy, and oophorectomy. Multivariable logistic regression was used to model postoperative complication rates, adjusting for ACS NSQIP risk of morbidity, demographic factors, ACS NSQIP-targeted procedure groups, and open versus laparoscopic surgery. RESULTS: Of 9172 intra-abdominal cases, 21.3% had preoperative esophageal disease (19.6% GERD and 1.7% other). After adjustment, patients with GERD were at higher risk for experiencing a number of complications, including all-cause 30-d complication (odds ratio [OR] = 1.21, 95% confidence interval [CI] 1.05-1.41, P = 0.044), renal complication (OR = 1.43, 95% CI 1.09-1.87, P = 0.036), wound complication (OR = 1.40, 95% CI 1.10-1.79, P = 0.028), and readmission within 30 d (OR = 1.66, 95% CI 1.35-2.04, P < 0.001). CONCLUSIONS: Preoperative GERD is associated with increased postoperative complication rate. Surgeons should consider assessing GERD in patients undergoing abdominal operations.

Rationale and Design of the "Safety and Efficacy of the Combination of Loop with Thiazide-type Diuretics in Patients with Decompensated Heart Failure (CLOROTIC) Trial:" A Double-Blind, Randomized, Placebo-Controlled Study to Determine the Effect of Combined Diuretic Therapy (Loop Diuretics With Thiazide-Type Diuretics) Among Patients With Decompensated Heart Failure.

BACKGROUND: Fluid overload refractory to loop diuretic therapy can complicate acute or chronic heart failure (HF) management. The Safety and Efficacy of the Combination of Loop with Thiazide-type Diuretics in Patients with Decompensated Heart Failure (CLOROTIC) trial (Clinicaltrials.gov identifier NCT01647932) will test the hypothesis that blocking distal tubule sodium reabsorption with hydrochlorothiazide can antagonize the renal adaptation to chronic loop diuretic therapy and improve diuretic resistance. METHODS: CLOROTIC is a randomized, placebo-controlled, double-blind, multicenter study. Three hundred and four patients with decompensated HF will be randomly assigned to receive hydrochlorothiazide or placebo in addition to a furosemide regimen. The main inclusion criteria are: age ≥18 years, history of chronic HF (irrespective of etiology and/or ejection fraction), admission for acute decompensation, and previous treatment with an oral loop diuretic for at least 1 month before randomization. The 2 coprimary endpoints are changes in body weight and changes in patient-reported dyspnea during hospital admission. Morbidity, mortality, and safety aspects will also be addressed. CONCLUSIONS: CLOROTIC is the first large-scale trial to evaluate whether the addition of a thiazide diuretic (hydrochlorothiazide) to a loop diuretic (furosemide) is a safe and effective strategy for improving congestive symptoms resulting from HF. This trial will provide important information and will therefore have a major impact on treatment strategies and future trials in these patients.

Utility of the bispectral index for assessing natural physiological sleep stages in children and young adults.

Polysomnography (PSG) is the gold standard for the analysis of sleep architecture but is not always available in routine practice, as it is time consuming and cumbersome for patients. Bispectral index (BIS), developed to quantify the deepness of general anesthesia, may be used as a simplified tool to evaluate natural sleep depth. We objectively recorded sleep architecture in young patients using the latest BIS Vista monitor and correlated BIS values with PSG sleep stages in order to determine BIS thresholds. Patients, referred for the screening of sleep apnea/hypopnea syndrome or differential diagnosis of hypersomnia were recruited. Overnight PSG and BIS were performed simultaneously. BIS values were averaged for each sleep stage. Pre-sleep wakefulness (W) and wake after sleep onset (WASO) were also differentiated. BIS values were discarded for a signal quality index <90 %. ROC curves were plotted to discriminate sleep stages from each other. Twelve patients (5.7-29.3 years old) were included. Mean BIS values were 83 ± 8, 76 ± 12, 77 ± 11, 70 ± 10, 43 ± 10, and 75 ± 10 for W, WASO, N1, N2, N3 and R (REM) stages, respectively. BIS failed to distinguish W, WASO, N1 and R stages. BIS threshold that identified stage N2 was <73 (AUC = 0.784, p < 0.001) with low sensitivity (75 %) and poor specificity (64 %). BIS threshold that identified stage N3 was <55 (AUC = 0.964, p < 0.001) with an 87 %-sensitivity and a 93 %-specificity. BIS identified stage N3 with satisfactory sensitivity and specificity but is limited by its inability to distinguish REM sleep from wake. Further studies combining BIS with chin electromyogram and/or electrooculogram could be of interest.

The Antinociceptive Effects of Tramadol and/or Gabapentin on Rat Neuropathic Pain Induced by a Chronic Constriction Injury.

Preclinical Research The current work evaluates the interaction between two commonly used drugs, tramadol (Tra) and gabapentin (Gbp). Dose-response curves (DRC) and isobolographic analysis were used to confirm their synergistic antihyperalgesic and anti-allodynic responses in a rat neuropathic pain model involving chronic constriction injury of the sciatic nerve and in von Frey and acetone tests. Tra and Gbp produced dose-dependent antihyperalgesic and anti-allodynic effects. Dose-response studies of combinations of Tra and Gbp in combination showed the DRC was leftward-shifted compared to the DRCs for each compound alone. One combination demonstrated both antihyperalgesic and anti-allodynic effects greater than those observed after individual administration. The remaining combinations demonstrated an additive effect. The Tra+Gbp combination demonstrated a potentiative effect with smaller doses of Tra. Additionally, it was determined lethal dose 50 (LD50 ) of Tra alone and tramadol + Gbp 10 using mice to 48 h post administration. The DRC (death) were similar for Tra alone and in Tra in combination, despite the improved effectiveness of Tra in the presence of GBP, 10 mg/kg. A combination of these drugs could be effective in neuropathic pain therapy because they can produce potentiative (at a low dose) or additive effects. Drug Dev Res 77 : 217-226, 2016. © 2016 Wiley Periodicals, Inc.