Search

Non-alcoholic fatty liver disease (NAFLD) is one of the most common causes of chronic liver disease in adults and children worldwide. NAFLD has become a severe health issue and it can progress towards a more severe form of the disease, the non-alcoholic steatohepatitis (NASH). A combination of environmental factors, host genetics, and gut microbiota leads to excessive accumulation of lipids in the liver (steatosis), which may result in lipotoxicity and trigger hepatocyte cell death, liver inflammation, fibrosis, and pathological angiogenesis. NASH can further progress towards liver cirrhosis and cancer. Over the last few years, cell-derived extracellular vesicles (EVs) have been identified as effective cell-to-cell messengers that transfer several bioactive molecules in target cells, modulating the pathogenesis and progression of NASH. In this review, we focused on recently highlighted aspects of molecular pathogenesis of NASH, mediated by EVs via their bioactive components. The studies included in this review summarize the state of art regarding the role of EVs during the progression of NASH and bring novel insight about the potential use of EVs for diagnosis and therapeutic strategies for patients with this disease.

Background: Male community health workers (CHWs) have rarely been studied as an addition to the female community health workforce to improve access and care for reproductive, maternal, newborn, and child health (RMNCH). Objective: To examine how male health activists (MHAs) coordinated RMNCH responsibilities with existing female health workers in an Indian context. Materials and Methods: Interviews from male and female CHWs were coded around community-based engagement, outreach services, and links to facility-based care. Results: Community-based engagement: MHAs completed tasks both dependent and independent of their gender, such as informing couples on safe RMNCH care in the antenatal and postnatal periods. MHAs motivated males on appropriate family planning methods, demonstrating clear gendered responsibility. Outreach services: MHAs were most valuable traveling to remote areas to inform about and bring mothers and children to community health events, with this division of labor appreciated by female health workers. Link to facility-based services: MHAs were recognized as a welcome addition accompanying women to health facilities for delivery, particularly in nighttime. Conclusion: This study demonstrates the importance of gendered CHW roles and male-female task-sharing to improve access to community health events, outreach services, and facility-based RMNCH care.

Pediatric acute liver failure (PALF) is a progressive, potentially fatal clinical syndrome occurring in previously healthy children. Our study aimed to determine the current leading causes of PALF in a single center in Germany, identifying possible prognostic markers. Thirty-seven pediatric patients with PALF were included. Medical records were reviewed for demographic, laboratory and clinical data. Laboratory results on admission and at peak value, PELD and MELD score on admission, and intensive care support were assessed. Fifteen patients recovered spontaneously, 14 died without transplantation, and 8 received a liver transplant. Patients who survived were significantly older than patients who died. Specific causes of PALF could be identified as infectious diseases (16%), metabolic diseases (14%), toxic liver injury (11%), immunologic diseases (8%), or vascular diseases (8%). Causes of PALF remained indeterminate in 43%. High ammonia, low albumin, and low ALT levels on admission were associated with worse outcome. Absence of need of ventilation, hemodialysis, and circulatory support predicted spontaneous recovery. In conclusion, infections are the most common known cause of PALF. However, in a large proportion of patients the cause for PALF remains cryptic. Ammonia and albumin levels may be of prognostic value to predict outcomes.

Abstract: In order to detect virulence factors in Shiga toxin-producing Escherichia coli (STEC) isolates and investigate the antimicrobial resistance profile, rectal swabs were collected from healthy sheep of the races Santa Inês and Dorper. Of the 115 E. coli isolates obtained, 78.3% (90/115) were characterized as STEC, of which 52.2% (47/90) carried stx1 gene, 33.3% (30/90) stx2 and 14.5% (13/90) both genes. In search of virulence factors, 47.7% and 32.2% of the isolates carried the genes saa and cnf1. According to the analysis of the antimicrobial resistance profile, 83.3% (75/90) were resistant to at least one of the antibiotics tested. In phylogenetic classification grouped 24.4% (22/90) in group D (pathogenic), 32.2% (29/90) in group B1 (commensal) and 43.3% (39/90) in group A (commensal). The presence of several virulence factors as well as the high number of multiresistant isolates found in this study support the statement that sheep are potential carriers of pathogens threatening public health.

Objective: Preclinical medical student electives are prevalent at medical schools across the United States, but the range of electives available and their impact on medical student education are not well described in the literature. The objective of this article is to review the literature relating to preclinical medical student electives and their impact on medical student educational outcomes. Methods: We reviewed studies that met the following criteria: English-language articles describing preclinical US-based medical electives. We used PubMed journal databases and limited our search for the time period 1999–2014. We excluded electives based in other countries or electives designed for third or fourth year students. Data abstracted included the topic of the elective, qualitative descriptions of the electives, and any associated surveys or exam data associated with the electives. Data were synthesized using descriptive tables sorting electives by broad topic. Reported outcomes and statistical methods were analyzed to assess study quality. Results: We found a wide range of subjects taught in the form of preclinical medical school electives. We identified electives in clinical skills, the humanities, student lifestyle, specialty-specific electives, and an assortment of other miscellaneous electives. Surveys and exams administered to students showed that the electives were universally well received by students. Of the 37 electives identified, 15 electives used quantitative objective assessments, such as knowledge exams, while the remaining tended to use student self-reported results. Conclusions: Preclinical medical student electives are prevalent at medical schools across the United States and have a significant impact on medical student education.

Background & aimsBreast regression protein 39 (BRP39) (Chi3L1) and its human homolog YKL-40, is an established biomarker of liver fibrosis in nonalcoholic steatohepatitis (NASH) patients, but its role in NASH pathogenesis remains unclear. We recently identified Chi3L1 as one of the top up-regulated genes in mice with inducible gain-of-function NOD-like receptor protein 3 (NLRP3) activation that mimics several liver features of NASH. This study aimed to investigate the effects of BRP39 deficiency on NLRP3-induced liver inflammation using tamoxifen-inducible Nlrp3 knockin mice sufficient (Nlrp3A350V CRT) and deficient for BRP39 (Nlrp3A350V/BRP-/- CRT).MethodsUsing Nlrp3A350V CRT mice and Nlrp3A350V BRP-/- CRT, we investigated the consequences of BRP39 deficiency influencing NLRP3-induced liver inflammation.ResultsOur results showed that BRP39 deficiency in NLRP3-induced inflammation improved body weight and liver weight. Moreover, liver inflammation, fibrosis, and hepatic stellate cell activation were reduced significantly, corresponding to significantly decreased Ly6C+ infiltrating macrophages, CD68+ osteopontin-positive hepatic lipid-associated macrophages, and activated Lymphocyte antigen 6 complex locus G6D positive (Ly6G+) and citrullinated histone H3 postivie (H3Cit+) neutrophil accumulation in the liver. Further investigation showed that circulatory neutrophils from NLRP3-induced BRP39-deficient mice have impaired chemotaxis and migration ability, and this was confirmed by RNA bulk sequencing showing reduced immune activation, migration, and signaling responses in neutrophils.ConclusionsThese data showcase the importance of BRP39 in regulating the NLRP3 inflammasome during liver inflammation and fibrotic NASH by altering cellular activation, recruitment, and infiltration during disease progression, and revealing BRP39 to be a potential therapeutic target for future treatment of inflammatory NASH and its associated diseases.

Leptospirosis is an emerging zoonotic disease with more than 1 million cases annually. Currently there is lack of evidence for signaling pathways involved during the infection process of Leptospira. In our comprehensive genomic analysis of 20 Leptospira spp. we identified seven pathogen-specific Two-Component System (TCS) proteins. Disruption of two these TCS genes in pathogenic Leptospira strain resulted in loss-of-virulence in a hamster model of leptospirosis. Corresponding genes lvrA and lvrB (leptospira virulence regulator) are juxtaposed in an operon and are predicted to encode a hybrid histidine kinase and a hybrid response regulator, respectively. Transcriptome analysis of lvr mutant strains with disruption of one (lvrB) or both genes (lvrA/B) revealed global transcriptional regulation of 850 differentially expressed genes. Phosphotransfer assays demonstrated that LvrA phosphorylates LvrB and predicted further signaling downstream to one or more DNA-binding response regulators, suggesting that it is a branched pathway. Phylogenetic analyses indicated that lvrA and lvrB evolved independently within different ecological lineages in Leptospira via gene duplication. This study uncovers a novel-signaling pathway that regulates virulence in pathogenic Leptospira (Lvr), providing a framework to understand the molecular bases of regulation in this life-threatening bacterium.

OBJECTIVE:The race for finding effective treatments for nonalcoholic fatty liver disease (NAFLD) has been slowed down by the high screen-failure rate for including patients in trials due to the lack of a noninvasive biomarker that can identify patients with significant disease. Recently, Wisteria floribunda agglutinin-positive Mac-2-binding protein (WFA+ -M2BP) has shown promise in predicting liver fibrosis. The aims of this study were to evaluate the utility of WFA+ -M2BP as a biomarker to sub-classify patients with NAFLD according to their disease severity and to assess its correlation with histologic features of NAFLD. METHODS:Patients undergoing biopsy for clinical suspicion of NAFLD and healthy controls were included. Patients with NAFLD were classified into: NAFL, early NASH (F0-F1), fibrotic NASH (F2-F3), and NASH cirrhosis (F4). Levels of WFA+ -M2BP in sera was measured by a HISCL™ M2BPGi™ assay kit using an automated immunoanalyzer (HISCL™-800; Sysmex, Kobe, Japan). Analysis of covariance was used to assess difference in WFA+ -M2BP between the groups and Spearman's correlation coefficients were used to assess correlation with histological features. RESULTS:Our cohort consisted of 20 healthy controls and 198 patients with biopsy-proven NAFLD divided as follows: 52 with NAFL, 62 with early NASH, 52 with fibrotic NASH, and 32 with NASH cirrhosis. WFA+ -M2BP level was found to be significantly increased in the fibrotic NASH and NASH cirrhosis groups compared to healthy controls and those with early NAFLD after adjusting for age, gender and BMI. Furthermore, patients with NASH cirrhosis had significantly higher WFA+ -M2BP levels (2.4[1.5, 4.2] C.O.I (Cut-off Index)) than those with fibrotic NASH (1.2[0.79, 1.9]), p < 0.001. WFA+ -M2BP level had moderate correlation with inflammation, ballooning and NAFLD activity score and strong correlation with fibrosis stage. Additionally, ROC curve analysis demonstrated that WFA+ -M2BP accurately differentiated F2-4 from F0-F1. CONCLUSION:In a large cohort of patients with the full spectrum of NAFLD, WFA+ -M2BP levels predicted the presence of advanced disease and correlated strongly with fibrosis stage.

[This corrects the article DOI: 10.1371/journal.pone.0202226.].

The recent emergence of the poultry bacterial pathogen Mycoplasma gallisepticum (MG) in free-living house finches (Haemorhous mexicanus), which causes mycoplasmal conjunctivitis in this passerine bird species, resulted in a rapid coevolutionary arms-race between MG and its novel avian host. Despite extensive research on the ecological and evolutionary dynamics of this host–pathogen system over the past two decades, the immunological responses of house finches to MG infection remain poorly understood. We developed seven new probe-based one-step quantitative reverse transcription polymerase chain reaction assays to investigate mRNA expression of house finch cytokine genes (IL1B, IL6, IL10, IL18, TGFB2, TNFSF15, and CXCLi2, syn. IL8L). These assays were then used to describe cytokine transcription profiles in a panel of 15 house finch tissues collected at three distinct time points during MG infection. Based on initial screening that indicated strong pro-inflammatory cytokine expression during MG infection at the periorbital sites in particular, we selected two key house finch tissues for further characterization: the nictitating membrane, i.e., the internal eyelid in direct contact with MG, and the Harderian gland, the secondary lymphoid tissue responsible for regulation of periorbital immunity. We characterized cytokine responses in these two tissues for 60 house finches experimentally inoculated either with media alone (sham) or one of two MG isolates: the earliest known pathogen isolate from house finches (VA1994) or an evolutionarily more derived isolate collected in 2006 (NC2006), which is known to be more virulent. We show that the more derived and virulent isolate NC2006, relative to VA1994, triggers stronger local inflammatory cytokine signaling, with peak cytokine expression generally occurring 3–6 days following MG inoculation. We also found that the extent of pro-inflammatory interleukin 1 beta signaling was correlated with conjunctival MG loads and the extent of clinical signs of conjunctivitis, the main pathological effect of MG in house finches. These results suggest that the pathogenicity caused by MG infection in house finches is largely mediated by host pro-inflammatory immune responses, with important implications for the dynamics of host–pathogen coevolution.

Alcoholic liver disease (ALD), a significant health problem, progresses through the course of several pathologies including steatosis, steatohepatitis, fibrosis, and cirrhosis. There are no effective FDA-approved medications to prevent or treat any stages of ALD, and the mechanisms involved in ALD pathogenesis are not well understood. Bioactive lipid metabolites play a crucial role in numerous pathological conditions, as well as in the induction and resolution of inflammation. Herein, a hepatic lipidomic analysis was performed on a mouse model of ALD with the objective of identifying novel metabolic pathways and lipid mediators associated with alcoholic steatohepatitis, which might be potential novel biomarkers and therapeutic targets for the disease. We found that ethanol and dietary unsaturated, but not saturated, fat caused elevated plasma ALT levels, hepatic steatosis and inflammation. These pathologies were associated with increased levels of bioactive lipid metabolites generally involved in pro-inflammatory responses, including 13-hydroxy-octadecadienoic acid, 9,10- and 12,13-dihydroxy-octadecenoic acids, 5-, 8-, 9-, 11-, 15-hydroxy-eicosatetraenoic acids, and 8,9- and 11,12-dihydroxy-eicosatrienoic acids, in parallel with an increase in pro-resolving mediators, such as lipoxin A4, 18-hydroxy-eicosapentaenoic acid, and 10S,17S-dihydroxy-docosahexaenoic acid. Elucidation of alterations in these lipid metabolites may shed new light into the molecular mechanisms underlying ALD development/progression, and be potential novel therapeutic targets.

Avian infectious laryngotracheitis (ILT) is a worldwide infectious disease that causes important economic losses in the poultry industry. Although it is known that ILT virus (ILTV) is present in Argentina, there is no information about the circulating strains. With the aim to characterize them, seven different genomic regions (thymidine kinase, glycoproteins D, G, B, C, and J, and infected cell polypeptide 4) were partially sequenced and compared between field samples. The gJ sequence resulted to be the most informative segment, it allowed the differentiation among field sample strains, and also, between wild and vaccine viruses. Specific changes in selected nucleotidic positions led to the definition of five distinct haplotypes. Tests for detection of clustering were run to test the null hypothesis that ILTV haplotypes were randomly distributed in time in Argentina and in space in the most densely populated poultry region of this country, Entre Rios. From this study, it was possible to identify a 46 km radius cluster in which higher proportions of haplotypes 4 and 5 were observed, next to a provincial route in Entre Rios and a significant decline of haplotype 5 between 2009 and 2011. Results here provide an update on the molecular epidemiology of ILT in Argentina, including data on specific genome segments that may be used for rapid characterization of the virus in the field. Ultimately, results will contribute to the surveillance of ILT in the country.

PurposeThe aim of this study is to evaluate long-term treatment outcome and toxicities among vestibular schwannoma (VS) patients treated with hypofractionated stereotactic radiotherapy (HSRT).Methods383 patients with unilateral VS treated with HSRT (25 Gy, five fractions) between 1995 and 2007 were retrospectively reviewed. Treatment failure was defined as requiring salvage microsurgery. Posttreatment new/progressive clinical symptoms or increases in baseline tumor volume (BTV) due to treatment effect or progression were noted. Symptom outcomes were reported as baseline and posttreatment ± improvement, respectively. Symptoms were grouped by cranial nerve (CN) VII or CNVIII. Audiometry was assessed baseline and posttreatment hearing. Patients were grouped as having greater than serviceable hearing [Gardner Robertson (GR) score 1–2] or less than non-serviceable hearing (GR score 3–5) by audiometry.ResultsMedian follow-up was 72.0 months. Nine (2.3%) experienced treatment failure. At last follow-up, 74 (19.3%) had new/progressive symptoms and were categorized as radiologic non-responders, whereas 300 (78.3%) had no tumor progression and were grouped as radiologic responders. Average pretreatment BTV for treatment failures, radiologic non-responders, and radiologic responders was 2.11, 0.44, and 1.87 cm3, respectively. Pretreatment CNVII and CNVIII symptoms were present in 9.4 and 93.4% of patients, respectively. Eight (24%) with pre-HSRT CNVII and 37 (10%) with pre-HSRT CNVIII symptoms recovered CN function post-HSRT. Thirty-five (9%) and 36 (9.4%) experienced new CNVII and CNVIII deficit, respectively, after HSRT. Of these, 20 (57%) and 18 (50%) recovered CNVII and CNVIII function, respectively, after HSRT. Evaluable audiograms were available in 199 patients. At baseline and at last follow-up, 65.8 and 36.2% had serviceable hearing, respectively. Fifty-one percent had preservation of serviceable hearing at last follow-up.ConclusionTreatment of VS with HSRT is effective with treatment success in 97.7% and an acceptable toxicity profile. Less than one-third of patients experience any new CNVII or CNVIII deficit posttreatment. Greater than 50% of patients with serviceable hearing at baseline maintained hearing function. Improved methods to differentiate treatment effect and tumor progression are needed.

ObjectiveDysphonia is common among patients with early stage glottic cancer. Laryngeal videostroboscopy (LVS) has not been routinely used to assess post-radiotherapy (RT) voice changes. We hypothesized that LVS would demonstrate improvement in laryngeal function after definitive RT for early-stage glottic cancer.Study designBlinded retrospective review of perceptual voice and stroboscopic parameters for patients with early glottic cancer and controls.SettingHigh-volume, single-institution academic medical center.Subjects and methodsFifteen patients underwent RT for Tis-T2N0M0 glottic cancer and were evaluated with serial LVS exams pre- and post-RT. Stroboscopic assessment included six parameters: vocal fold (VF) vibration, VF mobility, erythema/edema, supraglottic compression, glottic closure, and secretions. Grade, roughness, breathiness, asthenia, strain (GRBAS) voice perceptual scale was graded in tandem with LVS score. Assessments were grouped by time interval from RT: pre-RT, 0–4, 4–12, and >12 months post-RT.Results60 LVS exams and corresponding GRBAS assessments were reviewed. There were significant improvements in ipsilateral VF motion (P = 0.03) and vibration (P = 0.001) and significant worsening in contralateral VF motion (P 12 months post-RT. Glottic closure significantly worsened, most prominent >12 months post-RT (P = 0.01). Composite GRBAS scores were significantly improved across all post-RT intervals.ConclusionLVS proved to be a robust tool for assessing pre- and post-RT laryngeal function. We observed post-RT improvement in ipsilateral VF function, a decline in contralateral VF function, and decreased glottic closure. These results demonstrate that LVS can detect meaningful changes in VF and glottic function and support its use for post-RT evaluation of glottic cancer patients.

The acquisition of invasiveness is characteristic of tumor progression. Numerous genetic changes are associated with metastasis, but the mechanism by which a cell becomes invasive remains unclear. Expression of p85β, a regulatory subunit of phosphoinositide-3-kinase, markedly increases in advanced carcinoma, but its mode of action is unknown. We postulated that p85β might facilitate cell invasion. We show that p85β localized at cell adhesions in complex with focal adhesion kinase and enhanced stability and maturation of cell adhesions. In addition, p85β induced development at cell adhesions of an F-actin core that extended several microns into the cell z-axis resembling the skeleton of invadopodia. p85β lead to F-actin polymerization at cell adhesions by recruiting active Cdc42/Rac at these structures. In accordance with p85β function in invadopodium-like formation, p85β levels increased in metastatic melanoma and p85β depletion reduced invadopodium formation and invasion. These results show that p85β enhances invasion by inducing cell adhesion development into invadopodia-like structures explaining the metastatic potential of tumors with increased p85β levels.

We analyzed the nutritional composition and isotope ratios (C and N) of big-leaf mahogany (Swietenia macrophylla King) leaves in plantations established on contrasting soils and climates in Central America (State of Quintana Roo, Yucatán, México) and South America (State of Pará, Brazil). The objective was to determine the adaptability of this species to large differences in nutrient availability and rainfall regimes. Nutrient concentrations of leaves and soils were determined spectrophotometrically, and isotope ratios were measured using mass spectrometric techniques.In Pará soils were sandier, and acidic, receiving above 2000 mm of rain, whereas in Quintana Roo soils were predominantly clayey, with neutral to alkaline pH due to the underlying calcareous substrate, with about 1300 mm of rain. Leaf area/weight ratio was similar for both sites, but leaves from Quintana Roo were significantly smaller. Average N and K concentrations of adult leaves were similar, whereas Ca concentration was only slightly lower in Pará in spite of large differences in Ca availability. Leaves from this site had slightly higher P and lower Al concentrations. Differences in water use efficiency as measured by the natural abundance of 13C were negligible, the main effect of lower rainfall in Quintana Roo seemed to be a reduction in leaf area. The N isotope signature (δ15N) was more positive in Pará than in Quintana Roo, suggesting higher denitrification rates in the former. Results reveal a calciotrophic behavior and a remarkable capacity of mahogany to compensate for large differences in soil texture and nutrient availability.

Planning inclusive research should center meaningful engagement of co-researchers with intellectual and/or developmental disabilities to address issues that are important to their communities. There are a variety of approaches to planning research projects consistent with the guiding principles of inclusive research. We describe components of planning inclusive research by comparing two inclusive dissertation research projects. We organize our comparison into five sections: (1) initiating the projects, (2) team member characteristics and roles, (3) building and sustaining relationships, (4) accessibility in the research process, and (5) outcomes. We then discuss how contextual and team-level factors influence the process of planning inclusive research.

Non-Alcoholic Fatty Liver Disease (NAFLD) is a major form of chronic liver disease in the general population in relation to its high prevalence among overweight/obese individuals and patients with diabetes type II or metabolic syndrome. NAFLD can progress to steatohepatitis (NASH), fibrosis and cirrhosis and end-stage of liver disease but mechanisms involved are still incompletely characterized. Within the mechanisms proposed to mediate the progression of NAFLD, lipotoxicity is believed to play a major role. In the present study we provide data suggesting that microvesicles (MVs) released by fat-laden cells undergoing lipotoxicity can activate NLRP3 inflammasome following internalization by either cells of hepatocellular origin or macrophages. Inflammasome activation involves NF-kB-mediated up-regulation of NLRP3, pro-caspase-1 and pro-Interleukin-1, then inflammasome complex formation and Caspase-1 activation leading finally to an increased release of IL-1β. Since the release of MVs from lipotoxic cells and the activation of NLRP3 inflammasome have been reported to occur in vivo in either clinical or experimental NASH, these data suggest a novel rational link between lipotoxicity and increased inflammatory response.

Fasting to postprandial transition requires a tight adjustment of insulin secretion to its demand, so tissue (e.g., skeletal muscle) glucose supply is assured while hypo-/hyperglycemia are prevented. High muscle glucose disposal after meals is pivotal for adapting to increased glycemia and might drive insulin secretion through muscle-released factors (e.g., myokines). We hypothesized that insulin influences myokine secretion and then increases glucose-stimulated insulin secretion (GSIS). In conditioned media from human myotubes incubated with/without insulin (100 nmol/L) for 24 h, myokines were qualitatively and quantitatively characterized using an antibody-based array and ELISA-based technology, respectively. C57BL6/J mice islets and Wistar rat beta cells were incubated for 24 h with control and conditioned media from noninsulin- and insulin-treated myotubes prior to GSIS determination. Conditioned media from insulin-treated versus nontreated myotubes had higher RANTES but lower IL6, IL8, and MCP1 concentration. Qualitative analyses revealed that conditioned media from noninsulin- and insulin-treated myotubes expressed 32 and 23 out of 80 myokines, respectively. Islets incubated with conditioned media from noninsulin-treated myotubes had higher GSIS versus control islets (p

Neutrophils play an essential role during an inflammatory response, which is dependent on their rapid recruitment from the bone marrow to the vasculature. However, there is no information about the molecular signals that regulate neutrophil entry to circulation during an inflammatory process in humans. This is mainly due to the lack of a suitable model of study that contains similar set of molecules and that allows in vivo analyses. In this study, we used the zebrafish to assess the role of Cxcl8a, Cxcl8b, and Cxcr2 in neutrophil migration to blood circulation after injury. Using Tg(BACmpx:GFP)i114 transgenic embryos and two damage models (severe and mild), we developed in vivo lack of function assays. We found that the transcription levels of cxcl8a, cxcl8b, and cxcr2 were upregulated in the severe damage model. In contrast, only cxcr2 and cxcl8a mRNA levels were increased during mild damage. After knocking down Cxcl8a, neutrophil quantity decreased at the injury site, while Cxcl8b decreased neutrophils in circulation. When inhibiting Cxcr2, we observed a decrease in neutrophil entry to the bloodstream. In conclusion, we identified different functions for both Cxcl8 paralogues, being the Cxcl8b/Cxcr2 axis that regulates neutrophil entry to the bloodstream, while Cxcl8a/Cxcr2 regulates the migration to the affected area.

Two-component systems (TCS) are protein machineries that enable cells to respond to input signals. Histidine kinases (HK) are the sensory component, transferring information toward downstream response regulators (RR). HKs transfer phosphoryl groups to their specific RRs, but also dephosphorylate them, overall ensuring proper signaling. The mechanisms by which HKs discriminate between such disparate directions, are yet unknown. We now disclose crystal structures of the HK:RR complex DesK:DesR from Bacillus subtilis, comprising snapshots of the phosphotransfer and the dephosphorylation reactions. The HK dictates the reactional outcome through conformational rearrangements that include the reactive histidine. The phosphotransfer center is asymmetric, poised for dissociative nucleophilic substitution. The structural bases of HK phosphatase/phosphotransferase control are uncovered, and the unexpected discovery of a dissociative reactional center, sheds light on the evolution of TCS phosphotransfer reversibility. Our findings should be applicable to a broad range of signaling systems and instrumental in synthetic TCS rewiring.

En 1982 se firmó un convenio entre el Centro Internacional de Agricultura Tropical (CIAT), con sede en Palmira, y dos instituciones oficiales panameñas de investigación agrícola: el Instituto de Investigaciones Agropecuarias de Panamá (IDlAP) y la Facultad de Ciencias Agropecuarias (FCA) de la Universidad de Panamá. Este convenio se realizó entre 1982 y 1988 con el objetivo principal de obtener germoplasma mejorado de arroz para las condiciones de riego y secano favorecido. Este trabajo analiza el desarrollo de dicho convenio y los logros alcanzados. Se identificaron sitios claves para las evaluaciones de los. materiales segregantes (FrF8) Y se estableció un flujo del material genético el cual unía los distintos sitios de selección en Panamá con los programas de arroz del ClAT y las pruebas internacionales de arroz de América Latina y el Caribe. Se evaluaron 38305 líneas segregantes, incluyendo viveros internacionales; el porcentaje promedio de selección fue del 13%. La susceptibilidad a las principales enfermedades y a la sequía fueron los factores mas importantes de selección. Once variedades liberadas para diversos ecosistemas en siete países se originaron en este proyecto. Estos resultados indican la importancia de la colaboración interinstitucional e indican que los beneficios obtenidos se extendieron mas allá de las fronteras y tiempo contemplados inicialmente en este proyecto.

Se realiza un estudio retrospectivo, longitudinal y descriptivo, para describir el comportamiento de la morbilidad y mortalidad en la Unidad de Cuidados Intensivos No. 3 del Hospital Provincial Docente "Abel Santamaría Cuadrado" de Pinar del Río, en el 2010. El universo estuvo constituido por todos los pacientes que ingresaron en la propia Unidad de Cuidados Intensivos y que totalizaron 402. Los datos fueron obtenidos de los expedientes clínicos de los pacientes, así como de los departamentos de estadísticas y de anatomía patológica del hospital. Se confeccionó una base de datos utilizando la hoja de cálculo Microsoft Excel y se aplicaron medidas de resumen. Se realizaron los cálculos estadísticos utilizando para ello el Sistema Systat, prueba de ji cuadrado. Se calcularon la mortalidad bruta y neta según fórmulas estandarizadas. En los resultados se determinó un ligero predominio del sexo femenino respecto al masculino en todos los grupos de edades; el grupo de mayores de 60 años fue el de mayor número. El traumatismo craneoencefálico, la sepsis abdominal y el infarto agudo del miocardio resultaron ser las principales causas de admisión en la Unidad de Cuidados Intensivos. Los casos provinieron fundamentalmente del servicio de urgencias, medicina interna y recuperación quirúrgica. El shock séptico, el tromboembolismo pulmonar y la neumonía grave asociada al uso de ventilación mecánica fueron las principales causas de muerte. Las tasas de mortalidad bruta y neta se encontraron dentro de los parámetros esperados para este tipo de servicio.A retrospective, longitudinal and descriptive study was carried to describe morbidity and mortality behavior at No-3 Intensive Care Unit (ICU), "Abel Santamaria Cuadrado" University Hospital, Pinar del Rio during 2010. The target group was comprised of all patients (402) that were admitted in the ICU already mentioned in the period under study. Data were recorded from the clinical charts, from the departments of statistics and pathology service in the hospital. A database of Microsoft Excel System was created by means of summary measures. The statistical calculations were performed using Systat System and chi square test. Gross and net mortality rates were calculated following the standardized formulas. Results showed a slight prevalence of female sex in all age brackets; older than 60 years old presented the highest number. Cranio-encephalic trauma, abdominal sepsis and acute myocardial infarction were the main causes of admissions in the Intensive Care Units. Most of the cases were referred from the emergency service, internal medicine wards and surgical recovery. Septic shock, pulmonary thromboembolism and severe pneumonia associated with mechanical ventilation were the main causes of death. Gross and net mortality rates were among the expected parameters in this modality of medical service.

Copper is an essential ion that forms part of the active sites of many proteins. At the same time, an excess of this metal produces free radicals that are toxic for cells and organisms. Fish have been used extensively to study the effects of metals, including copper, present in food or the environment. It has been shown that different metals induce different adaptive responses in adult fish. However, until now, scant information has been available about the responses that are induced by waterborne copper during early life stages of fish. Here, acute toxicity tests and LC50 curves have been generated for zebrafish larvae exposed to dissolved copper sulphate at different concentrations and for different treatment times. We determined that the larvae incorporate and accumulate copper present in the medium in a concentration-dependent manner, resulting in changes in gene expression. Using a transgenic fish line that expresses enhanced green fluorescent protein (EGFP) under the hsp70 promoter, we monitored tissue-specific stress responses to waterborne copper by following expression of the reporter. Furthermore, TUNEL assays revealed which tissues are more susceptible to cell death after exposure to copper. Our results establish a framework for the analysis of whole-organism management of excess external copper in developing aquatic animals.

Oxidative stress is a core abnormality responsible for disease progression in nonalcoholic fatty liver disease (NAFLD). However, the pathways that contribute to oxidative damage in vivo are poorly understood. Our aims were to define the circulating profile of lipid oxidation products in NAFLD patients, the source of these products, and assess whether their circulating levels reflect histological changes in the liver. The levels of multiple structurally specific oxidized fatty acids, including individual hydroxy-eicosatetraenoic acids (HETE), hydroxy-octadecadenoic acids (HODE), and oxo-octadecadenoic acids (oxoODE), were measured by mass spectrometry in plasma at time of liver biopsy in an initial cohort of 73 and a validation cohort of 49 consecutive patients. Of the markers monitored, 9- and 13-HODEs and 9- and 13-oxoODEs, products of free radical-mediated oxidation of linoleic acid (LA), were significantly elevated in patients with nonalcoholic steatohepatitis (NASH), compared with patients with steatosis. A strong correlation was revealed between these oxidation products and liver histopathology (inflammation, fibrosis, and steatosis). Further analyses of HODEs showed equivalent R and S chiral distribution. A risk score for NASH (oxNASH) was developed in the initial clinical cohort and shown to have high diagnostic accuracy for NASH versus steatosis in the independent validation cohort. Subjects with elevated oxNASH levels (top tertile) were 9.7-fold (P < 0.0001) more likely to have NASH than those with low levels (bottom tertile). Collectively, these findings support a key role for free radical-mediated linoleic acid oxidation in human NASH and define a risk score, oxNASH, for noninvasive detection of the presence of NASH.

Chitinase-3-like 1 protein (CHI3L1) is a secreted glycoprotein, strongly correlated with fibrosis severity in chronic liver diseases including non-alcoholic steatohepatitis (NASH). However, the mechanisms by which CHI3L1 contributes to fibrogenesis remain undefined. Here, we showed that infiltrating monocyte-derived liver macrophages represent the main source of CHI3L1 in murine NASH. We developed a floxed CHI3L1 knock-out (KO) mouse to further study the cell-specific role of CHI3L1 ablation. Wildtype (WT) and myeloid cell-specific CHI3L1 KO mice (CreLyz) were challenged with a highly inflammatory and fibrotic dietary model of NASH by administering choline-deficient high-fat diet for 10 weeks. Macrophage accumulation and inflammatory cell recruitment were significantly ameliorated in the CreLyz group compared to WT (F4/80 IHC p

Se realizó un estudio prospectivo, longitudinal y descriptivo para describir los efectos inmediatos de la ventilación no invasiva en los pacientes con enfermedad pulmonar obstructiva crónica hipercápnica. Se Incluyeron en la muestra a los 35 pacientes que fueron admitidos a las Unidades de Cuidados Intensivos del Hospital "Abel Santamaría" de Pinar del Río del 1ro. de enero hasta el 31 de diciembre de 2006, con dicho diagnóstico. Como técnica de ventilación no invasiva se utilizó la presión de soporte administrada por diferentes tipos de ventiladores de presión positiva. Se solicitó su consentimiento a todos los pacientes para participar en el estudio. Para el análisis estadístico se utilizó la prueba de hipótesis de proporciones con un nivel de ajuste de á= 0.05, y no paramétrica para K muestras relacionadas de Friedman. Se observó que el grupo de edades de mayor incidencia de EPOC fue el de 55-74 años y el sexo femenino representó el triple del masculino. De 35 pacientes, abandonaron el tratamiento 4, de ellos 3 lo hicieron a la hora, y 1 a las seis horas. En la mayoría de los pacientes no existió fracaso ventilatorio. A las 6 horas de tratamiento todos los pacientes habían mejorado el nivel de conciencia y la mayoría no tenía cianosis. La PCO2 se normalizó a las 6h en la mayoría de los pacientes, al igual que el pH y la PO2. El número de complicaciones se reduce cuando se aplica ventilación no invasiva.A prospective, longitudinal and descriptive research was conducted aimed at describing the effects of the non-invasive ventilation in patients suffering from Hypercapnic Chronic Obstructive Pulmonary Disease. The sample included 35 patients, who were diagnosed with COPD, admitted at "Abel Santamaria" University Hospital in the Intensive Care Unit from January 1st to December 31st, 2006. Using supported pressure administered by different types of ventilators of positive pressure as a non-invasive ventilation technique. The consent of the patients to participate in the study was requested. To the statistical analysis the proportion hypothesis test was used having a level of adjustment of á= 0.05 and non-parametric to K related to Friedman's samples. Observing that, the group of 55-74 years old presented the highest incidence of COPD, female sex represented the triple over the male sex. Out of the 35 patients, 4 were weaned off ventilator, 3 of them at one-hour and the other one at 6 hours of treatment. Observing no-ventilatory failed in the majority of the patients. At six-hour treatment, all the patients improved the level of consciousness and cyanosis was not observed. The PCO2 was normal at six- treatment hour in the majority of patients as well as the pH and the PO2. The number of complications decreased when non-invassive ventilation was used.

Se realizó un estudio prospectivo, longitudinal y descriptivo, a fin de caracterizar los aspectos clínicos epidemiológicos de la enfermedad coronaria aguda y los cuidados de enfermería en el Hospital "Abel Santamaría" de Pinar del Río, en el período del 1º. de Julio de 2006 al 30 de junio de 2007. El universo estuvo constituido por los 1784 pacientes ingresados en la Unidad de Cuidados Intensivos Emergentes y la muestra incluyó los 300 diagnosticados de Síndrome Coronario Agudo. Los datos fueron recolectados de los expedientes clínicos y se analizaron las siguientes variables: edad, sexo, color de la piel, intervalo de tiempo entre el inicio del dolor y admisión en la Unidad de Emergencias, tipo de evento coronario agudo y complicaciones. Se utilizó el Paquete Estadístico EPI Info 6 para el manejo de datos y análisis estadístico y solicitó consentimiento informado a los pacientes. Existió predominio de la enfermedad en hombres blancos de 60 años o más. La angina inestable aguda con cambios electrocardiográficos fue la enfermedad coronaria más diagnosticada, seguida del infarto agudo del miocardio. La mayoría de los pacientes acudieron antes de las seis horas de inicio del cuadro doloroso precordial. El fallo de bomba, las arritmias ventriculares malignas y el bloqueo aurículo ventricular, constituyeron las complicaciones más frecuentes y las que mayor mortalidad provocaron.A prospective, longitudinal and descriptive study was carried out aimed at characterizing the clinical-epidemiological aspects of the Acute Coronary Syndrome at "Abel Santamaria" University Hospital, Pinar del Rio during July 1st 2006 to June 30th 2007. The universe of the study was constituted by 1 784 patients admitted at the Intensive Coronary Care Unit and the sample included 300 diagnosed with Coronary Acute Syndrome. Data were collected from the clinical records of the patients and the following variables were analyzed: age, sex, race, interval of time between the onset of the pain and admission in the Emergency Unit, type of the acute coronary event and complications. EPI Info-6 was used as a Statistical Package to the control of data and statistical analysis. The informed consent was requested to the patients. The disease prevailed in Caucasian, 60 years old or older men. Being Acute Unstable Angina with electrocardiographic changes was the coronary syndrome mostly diagnosed, followed by Acute Myocardial Infarction. Most of the patients attended to the hospital before the 6 hours of the onset of the precordial pain. The heart failure, malignant ventricular arrhythmias and the atrioventricular block were the most frequent complications and the ones provoking a greater mortality rate.

Se realizó un estudio ambispectivo y descriptivo en 117 pacientes egresados vivos o fallecidos con el diagnóstico de meningoencefalitis bacteriana en los años de (2002 a 2006), en los Hospitales Provinciales "León Cuervo" y "Abel Santamaría". Para la validación estadística se aplicó la prueba estadística no paramétrica x², y el test de hipótesis de proporciones para grupos independientes, para un nivel de ajuste de a=0.05. La mayor parte de los pacientes con meningoencefalitis bacteriana aguda y subaguda se encontraba entre los 15 y los 59 años de edad, disminuyendo la frecuencia de la enfermedad a medida que avanza la edad, la mayor mortalidad se observó en los de 60 años o más, siendo este hecho altamente significativo. Los síntomas y signos más frecuentes fueron fiebre, cefalea, rigidez de nuca y alteraciones de la conciencia; la ausencia de fiebre, la presencia de vómitos, alteraciones de la conciencia, convulsiones, otros signos meníngeos, así como petequias, constituyeron signos de mal pronóstico. Las complicaciones más frecuentes resultaron ser edema cerebral, neumonía aguda nosocomial e insuficiencia respiratoria aguda no asociada al SIRPA, todas con diferencias estadísticas altamente significativas respecto a la probabilidad de morir por ellas. Los agentes etiológicos fueron, en orden decreciente, Streptococcus pneumoniae, Staphylococcus aureus, Staphylococcus epidermidis, Enterobacter aerogenes, Neisseria meningitidis y Haemophilus influenzae. El cultivo resultó negativo en la mayoría de los casos que usaron antibioticoterapia previa al diagnóstico.A descriptive study was performed from 2002 _ 2006 in 117 patients with a bacterial meningoencephalitis diagnosis being discharged alive or death in "Abel Santamaría" or "Leon Cuervo Rubio" hospitals. The non _ parametric statistical X2 testing was used for the statistical validation as well as the hypothesis testing of ratios for independent groups, a fitted value of á=0.05. Most of patients with acute and sub acute bacterial meningoencephalitis were in 15 and 59 year age range decreasing the frequency of the disease with the age advancing , the highest mortality rate was observed at 60 years old or over being considered very significant . The most predisposing factors were: otitis media, acute community pneumonia and sinusitis, some of them partially treated or not. Fever, headache, neck stiffness and consciousness disorders were the most frequent symptoms and signs and the absence of fever, the occurrence of vomits, consciousness disorders, convulsions, and other meningeal signs and petechiae were considered as a bad prognosis. The most frequent complications were cerebral edema, nosocomial acute pneumonia and acute respiratory failure no associated to SIRPA having all of them very significant statistical differences and leading to a probable death. The etiological agents were: Streptococcus pneumoniae, Staphylococcus aureus, Staphylococcus epidermidis, Enterobacter aerogenes, Neisseria meningitides and Haemophilus influenzae. In most of cases given antibiotic therapy before diagnosis the culture was negative.

Leptospirosis, caused by spirochetes of the genus Leptospira, is a globally widespread, neglected and emerging zoonotic disease. While whole genome analysis of individual pathogenic, intermediately pathogenic and saprophytic Leptospira species has been reported, comprehensive cross-species genomic comparison of all known species of infectious and non-infectious Leptospira, with the goal of identifying genes related to pathogenesis and mammalian host adaptation, remains a key gap in the field. Infectious Leptospira, comprised of pathogenic and intermediately pathogenic Leptospira, evolutionarily diverged from non-infectious, saprophytic Leptospira, as demonstrated by the following computational biology analyses: 1) the definitive taxonomy and evolutionary relatedness among all known Leptospira species; 2) genomically-predicted metabolic reconstructions that indicate novel adaptation of infectious Leptospira to mammals, including sialic acid biosynthesis, pathogen-specific porphyrin metabolism and the first-time demonstration of cobalamin (B12) autotrophy as a bacterial virulence factor; 3) CRISPR/Cas systems demonstrated only to be present in pathogenic Leptospira, suggesting a potential mechanism for this clade's refractoriness to gene targeting; 4) finding Leptospira pathogen-specific specialized protein secretion systems; 5) novel virulence-related genes/gene families such as the Virulence Modifying (VM) (PF07598 paralogs) proteins and pathogen-specific adhesins; 6) discovery of novel, pathogen-specific protein modification and secretion mechanisms including unique lipoprotein signal peptide motifs, Sec-independent twin arginine protein secretion motifs, and the absence of certain canonical signal recognition particle proteins from all Leptospira; and 7) and demonstration of infectious Leptospira-specific signal-responsive gene expression, motility and chemotaxis systems. By identifying large scale changes in infectious (pathogenic and intermediately pathogenic) vs. non-infectious Leptospira, this work provides new insights into the evolution of a genus of bacterial pathogens. This work will be a comprehensive roadmap for understanding leptospirosis pathogenesis. More generally, it provides new insights into mechanisms by which bacterial pathogens adapt to mammalian hosts.

Much information on parental perspectives on the return of individual research results (IRR) in pediatric genomic research is based on hypothetical rather than actual IRR. Our aim was to understand how the expected utility to parents who received IRR on their child from a genetic research study compared to the actual utility of the IRR received.We conducted individual telephone interviews with parents who received IRR on their child through participation in the Manton Center for Orphan Disease Research Gene Discovery Core (GDC) at Boston Children's Hospital (BCH).Five themes emerged around the utility that parents expected and actually received from IRR: predictability, management, family planning, finding answers, and helping science and/or families. Parents expressing negative or mixed emotions after IRR return were those who did not receive the utility they expected from the IRR. Conversely, parents who expressed positive emotions were those who received as much or greater utility than expected.Discrepancies between expected and actual utility of IRR affect the experiences of parents and families enrolled in genetic research studies. An informed consent process that fosters realistic expectations between researchers and participants may help to minimize any negative impact on parents and families.

Se realizó un estudio observacional, descriptivo y transversal sobre los resultados obtenidos por los estudiantes de 3er año de la carrera de Medicina en la asignatura Propedéutica Clínica durante el 5to semestre de la carrera de Medicina del curso 2006- 2007, con el objetivo de exponer dichos resultados, teniendo en cuenta los diferentes modelos de enseñanza donde se encuentran insertados. Para ello fue necesario el análisis de las evaluaciones, tanto de los que se encuentran en el PROYECTO POLICLÍNICO UNIVERSITARIO como de los del modelo tradicional y experimental en el que participó un número menor de estudiantes. Además se recogieron los criterios y recomendaciones de los estudiantes y Profesores Integrales que imparten esta asignatura. Los datos fueron recogidos de las actas entregadas y de los registros de asistencia y control a clases, además de una encuesta aplicada a estudiantes y profesores que se encuentran recibiendo e impartiendo la asignatura. Los resultados fueron presentados en tablas y gráficos. Como resultados de nuestra investigación obtuvimos que los estudiantes que recibieron la asignatura en la APS con los profesores integrales obtuvieran calificaciones similares a los que la recibieron por el Método Tradicional, con una tendencia a mejores resultados. Los estudiantes encuestados que se encuentran en el Proyecto Policlínico Universitario recibiendo la asignatura manifestaron su total satisfacción con el Proyecto y refieren continuar en el mismo. Los profesores que imparten la Propedéutica Clínica, se encuentran en total disposición de continuar impartiéndola en cursos posteriores.An observational, descriptive and cross-sectional study about the results obtained for medical students being currently in the 3rd. academic year, and taking the subject "Clinical propedeutics" during the 5th. term of the academic course 2006-2007 was conducted with the purpose of showing these results and taking into account the different teaching models where these students are enrolled. It was necessary to analyze the evaluations of those students enrolled in the important experience of the University Outpatient Clinic Project, besides those in the same term, but enrolled in the model of traditional medical studies. Data also showed another third model (called "experimental"), recording the participation of a minor group of these students. In the study those criteria, recommendations and projections of the students were gathered, as well as the opinions of professors (specialists and residents in Comprehensive Medicine), who teach the subject in Primary Health Care. Data studied were collected from the official documents at the Department of Medical Studies, and from the records of attendance and control to lectures. Besides, a survey was applied to students taking the subject and professors teaching it on the settling of Primary health Care, these results were recorded in tables and charts. The results of the research were: Those students who took the subject in the setting of Primary Health Care with comprehensive professors obtained similar grades as those in the traditional method, having those from the Primary Health Care a trend to better results. Students inquired in the University Outpatient Clinic Project who were taking the subject expressed satisfaction with the project, and the majority will continue in this model of medical studies to take the rest of the subjects, Those professors teaching Clinical Propedeutics in Primarty Health Care are prepared to teach the same subject in future academic courses.

Se realizó una valoración del diseño curricular del Programa del Internado profesionalizante que se imparte en el 6to año de la Carrera de Medicina en el cual se analizó el objeto de estudio de dicho programa, así como los objetivos, contenidos, métodos de enseñanza, medios de enseñanza, formas de organizar esta enseñanza y el sistema de evaluación de dicho programa. En nuestro análisis pudimos concluir que con el Diseño de Internado Profesionalizante el plan de estudios gana en pertinencia al desarrollar el último año a tiempo completo en los escenarios reales en que el egresado habrá de desempeñarse como médico General Integral Básico, permitiéndole un mayor vínculo con la práctica profesional, independencia en la actuación, responsabilidad con el trabajo y una estrecha relación con la comunidad. Todo esto se ha traducido en mejores resultados en el Examen Estatal y la opinión muy satisfactoria que sobre ellos han vertido las comunidades en las cuales han prestado sus servicios. No debemos dejar de mencionar, además, la meritoria labor que estos estudiantes han desarrollado en las funciones docentes como tutores de alumnos de años inferiores.An assessment of the curricular design for the Internship Program taught in the 6th academic year of medical major was carried out with the purpose of analyzing the object of study , objectives, contents, teaching methods, teaching aids, organization of learning and system of evaluation. The analysis showed that with the Internship Program the syllabus gained pertinence inserting those medical students enroll in 6th (last) academic year in professional practice, having independence in their performance, achieving responsibility towards work and a close relationship with the community. The fulfillment of these activities allow better results in the State Examination, and the communities where they carry out the Internship Program express a satisfactory opinion. It is worth to mention the task these students performed in the teaching process as tutors of medical students in lower academic courses.

Protein kinase CK1 is a ser/thr protein kinase family which has been identified in the cytosol cell fraction, associated with membranes as well as in the nucleus. Several isoforms of this gene family have been described in various organisms: CK1á, CK1ß, CK1δ, CK1å and CK1γ. Over the last decade, several members of this family have been involved in development processes related to wnt and sonic hedgehog signalling pathways. However, there is no detailed temporal information on the CK1 family in embryonic stages, even though orthologous genes have been described in several different vertebrate species. In this study, we describe for the first time the cloning and detailed expression pattern of five CK1 zebrafish genes. Sequence analysis revealed that zebrafish CK1 proteins are highly homologous to other vertebrate orthologues. Zebrafish CK1 genes are expressed throughout development in common and different territories. All the genes studied in development show maternal and zygotic expression with the exception of CK1å. This last gene presents only a zygotic component of expression. In early stages of development CK1 genes are ubiquitously expressed with the exception of CK1å. In later stages the five CK1 genes are expressed in the brain but not in the same way. This observation probably implicates the CK1 family genes in different and also in redundant functions. This is the first time that a detailed comparison of the expression of CK1 family genes is directly assessed in a vertebrate system throughout development

Background & Aims: Hepatic stellate cells (HSCs) play a key role in liver fibrosis in various chronic liver disorders including nonalcoholic fatty liver disease (NAFLD). The development of liver fibrosis requires a phenotypic switch from quiescent to activated HSCs. The trigger for HSC activation in NAFLD remain poorly understood. We investigated the role and molecular mechanism of extracellular vesicles (EVs) released by hepatocytes during lipotoxicity in modulation of HSC phenotype. Methods: EVs were isolated from fat-laden hepatocytes by differential centrifugation and incubated with HSCs. EV internalization and HSC activation, migration, and proliferation were assessed. Loss- and gain-of-function studies were performed to explore the potential role of peroxisome proliferator-activated receptor-γ (PPAR-γ)-targeting microRNAs (miRNAs) carried by EVs into HSC. Results: Hepatocyte-derived EVs released during lipotoxicity are efficiently internalized by HSCs resulting in their activation, as shown by marked up-regulation of profibrogenic genes (collagen-I, α-smooth muscle actin, and tissue inhibitor of metalloproteinases-2), proliferation, chemotaxis, and wound-healing responses. These changes were associated with miRNAs shuttled by EVs and suppression of PPAR-γ expression in HSCs. The hepatocyte-derived EV miRNA content included various miRNAs that are known inhibitors of PPAR-γ expression, with miR-128-3p being the most efficiently transferred. Furthermore, loss- and gain-of-function studies identified miR-128-3p as a central modulator of the effects of EVs on PPAR-γ inhibition and HSC activation. Conclusions: Our findings demonstrate a link between fat-laden hepatocyte-derived EVs and liver fibrosis and have potential implications for the development of novel antifibrotic targets for NAFLD and other fibrotic diseases. Keywords: Extracellular Vesicles, Hepatic Stellate Cell, Lipotoxicity, Liver Fibrosis, miRNAs

Background and aimsNucleotide-binding oligomerization domain-like receptor-family pyrin domain-containing 3 (NLRP3) inflammasome activation has been shown to result in liver fibrosis. Mechanisms and downstream signaling remain incompletely understood. Here, we studied the role of IL-18 in hepatic stellate cells (HSCs), and its impact on liver fibrosis.Approach and resultsWe observed significantly increased serum levels of IL-18 (128.4 pg/ml vs. 74.9 pg/ml) and IL-18 binding protein (BP; 46.50 ng/ml vs. 15.35 ng/ml) in patients with liver cirrhosis compared with healthy controls. Single cell RNA sequencing data showed that an immunoregulatory subset of murine HSCs highly expresses Il18 and Il18r1 . Treatment of cultured primary murine HSC with recombinant mouse IL-18 accelerated their transdifferentiation into myofibroblasts. In vivo , IL-18 receptor-deficient mice had reduced liver fibrosis in a model of fibrosis induced by HSC-specific NLRP3 overactivation. Whole liver RNA sequencing analysis from a murine model of severe NASH-induced fibrosis by feeding a choline-deficient, L-amino acid-defined, high fat diet showed that genes related to IL-18 and its downstream signaling were significantly upregulated, and Il18-/- mice receiving this diet for 10 weeks showed protection from fibrotic changes with decreased number of alpha smooth muscle actin-positive cells and collagen deposition. HSC activation triggered by NLRP3 inflammasome activation was abrogated when IL-18 signaling was blocked by its naturally occurring antagonist IL-18BP. Accordingly, we observed that the severe inflammatory phenotype associated with myeloid cell-specific NLRP3 gain-of-function was rescued by IL-18BP.ConclusionsOur study highlights the role of IL-18 in the development of liver fibrosis by its direct effect on HSC activation identifying IL-18 as a target to treat liver fibrosis.

The symposium, “Role of Nutrition in Alcoholic Liver Disease”, was held at the European Society for Biomedical Research on Alcoholism Congress on 9 October 2017 in Crete, Greece. The goal of the symposium was to highlight recent advances and developments in the field of alcohol and nutrition. The symposium was focused on experimental and clinical aspects in relation to the role of different types of dietary nutrients and malnutrition in the pathogenesis of alcoholic liver disease (ALD). The following is a summary of key research presented at this session. The speakers discussed the role of dietary fats and carbohydrates in the development and progression of alcohol-induced multi-organ pathology in animal models of ALD, analyzed novel nutrition-related therapeutics (specifically, betaine and zinc) in the treatment of ALD, and addressed clinical relevance of malnutrition and nutrition support in ALD. This summary of the symposium will benefit junior and senior faculty currently investigating alcohol-induced organ pathology as well as undergraduate, graduate, and post-graduate students and fellows.

Macrophage infiltration of adipose tissue during weight gain is a central event leading to the metabolic complications of obesity. However, what are the mechanisms attracting professional phagocytes to obese adipose tissue remains poorly understood. Here, we demonstrate that adipocyte-derived microparticles (MPs) are critical "find-me" signals for recruitment of monocytes and macrophages. Supernatants from stressed adipocytes stimulated the attraction of monocyte cells and primary macrophages. The activation of caspase 3 was required for release of these signals. Adipocytes exposed to saturated fatty acids showed marked release of MPs into the supernatant while common genetic mouse models of obesity demonstrate high levels of circulating adipocyte-derived MPs. The release of MPs was highly regulated and dependent on caspase 3 and Rho-associated kinase. Further analysis identified these MPs as a central chemoattractant in vitro and in vivo. In addition, intravenously transplanting circulating MPs from the ob/ob mice lead to activation of monocytes in circulation and adipose tissue of the wild type mice. These data identify adipocyte-derived MPs as novel "find me" signals that contributes to macrophage infiltration associated with obesity.

We present a case report of a patient with glioblastoma multiforme (GBM) complicated by extracranial metastasis (ECM) whose survival of nearly four years surpassed the anticipated life expectancy given numerous negative prognostic factors including EGFRvIII-mutation, unmethylated MGMT promoter status, and ECM. Interestingly, while this patient suffered from locally aggressive disease with multiple intracranial recurrences, the proximal cause of death was progressive extracranial disease and complications related to pulmonary metastases. Herein, we review potential mechanisms of ECM with an emphasis upon glioblastoma molecular and genetic profiles and the potential implications of targeted agents such as bevacizumab.