Liver sinusoidal cells eliminate blood-borne phage K1F.

Phage treatment has regained attention due to an increase in multiresistant bacteria. For phage therapy to be successful, phages must reach their target bacteria in sufficiently high numbers. Blood-borne phages are believed to be captured by macrophages in the liver and spleen. Since liver sinusoids also consist of specialized scavenger liver sinusoidal endothelial cells (LSECs) and Kupffer cells (KCs), this study investigated the contribution of both cell types in the elimination of Escherichia coli phage K1Fg10b::gfp (K1Fgfp) in mice. Circulatory half-life, organ, and hepatocellular distribution of K1Fgfp were determined following intravenous administration. Internalization of K1Fgfp and effects of phage opsonization on uptake were explored using primary mouse and human LSEC and KC cultures. When inoculated with 107 virions, >95% of the total K1Fgfp load was eliminated from the blood within 20 min, and 94% of the total retrieved K1Fgfp was localized to the liver. Higher doses resulted in slower elimination, possibly reflecting temporary saturation of liver scavenging capacity. Phage DNA was detected in both cell types, with a KC:LSEC ratio of 12:1 per population following cell isolation. Opsonization with plasma proteins increased time-dependent cellular uptake in both LSECs and KCs in vitro. Internalized phages were rapidly transported along the endocytic pathway to lysosomal compartments. Reduced viability of intracellular K1Fgfp corroborated inactivation following endocytosis. This study is the first to identify phage distribution in the liver at the hepatocellular level, confirming clearance of K1Fgfp performed mostly by KCs with a significant uptake also in LSECs.IMPORTANCEFaced with the increasing amounts of bacteria with multidrug antimicrobial resistance, phage therapy has regained attention as a possible treatment option. The phage field has recently experienced an emergence in commercial interest as research has identified new and more efficient ways of identifying and matching phages against resistant superbugs. Currently, phages are unapproved drugs in most parts of the world. For phages to reach broad clinical use, they must be shown to be clinically safe and useful. The results presented herein contribute to increased knowledge about the pharmacokinetics of the T7-like phage K1F in the mammalian system. The cell types of the liver that are responsible for rapid phage blood clearance are identified. Our results highlight the need for more research about appropriate dose regimens when phage therapy is delivered intravenously and advise essential knowledge about cell systems that should be investigated further for detailed phage pharmacodynamics.

Liver sinusoidal endothelial cells show reduced scavenger function and downregulation of Fc gamma receptor IIb, yet maintain a preserved fenestration in the Glmpgt/gt mouse model of slowly progressing liver fibrosis.

Liver sinusoidal endothelial cells (LSECs) are fenestrated endothelial cells with a unique, high endocytic clearance capacity for blood-borne waste macromolecules and colloids. This LSEC scavenger function has been insufficiently characterized in liver disease. The Glmpgt/gt mouse lacks expression of a subunit of the MFSD1/GLMP lysosomal membrane protein transporter complex, is born normal, but soon develops chronic, mild hepatocyte injury, leading to slowly progressing periportal liver fibrosis, and splenomegaly. This study examined how LSEC scavenger function and morphology are affected in the Glmpgt/gt model. FITC-labelled formaldehyde-treated serum albumin (FITC-FSA), a model ligand for LSEC scavenger receptors was administered intravenously into Glmpgt/gt mice, aged 4 months (peak of liver inflammation), 9-10 month, and age-matched Glmpwt/wt mice. Organs were harvested for light and electron microscopy, quantitative image analysis of ligand uptake, collagen accumulation, LSEC ultrastructure, and endocytosis receptor expression (also examined by qPCR and western blot). In both age groups, the Glmpgt/gt mice showed multifocal liver injury and fibrosis. The uptake of FITC-FSA in LSECs was significantly reduced in Glmpgt/gt compared to wild-type mice. Expression of LSEC receptors stabilin-1 (Stab1), and mannose receptor (Mcr1) was almost similar in liver of Glmpgt/gt mice and age-matched controls. At the same time, immunostaining revealed differences in the stabilin-1 expression pattern in sinusoids and accumulation of stabilin-1-positive macrophages in Glmpgt/gt liver. FcγRIIb (Fcgr2b), which mediates LSEC endocytosis of soluble immune complexes was widely and significantly downregulated in Glmpgt/gt liver. Despite increased collagen in space of Disse, LSECs of Glmpgt/gt mice showed well-preserved fenestrae organized in sieve plates but the frequency of holes >400 nm in diameter was increased, especially in areas with hepatocyte damage. In both genotypes, FITC-FSA also distributed to endothelial cells of spleen and bone marrow sinusoids, suggesting that these locations may function as possible compensatory sites of clearance of blood-borne scavenger receptor ligands in liver fibrosis.

Infection of liver sinusoidal endothelial cells with Muromegalovirus muridbeta1 involves binding to neuropilin-1 and is dynamin-dependent.

Liver sinusoidal endothelial cells (LSEC) are scavenger cells with a remarkably high capacity for clearance of several blood-borne macromolecules and nanoparticles, including some viruses. Endocytosis in LSEC is mainly via the clathrin-coated pit mediated route, which is dynamin-dependent. LSEC can also be a site of infection and latency of betaherpesvirus, but mode of virus entry into these cells has not yet been described. In this study we have investigated the role of dynamin in the early stage of muromegalovirus muridbeta1 (MuHV-1, murid betaherpesvirus 1, murine cytomegalovirus) infection in mouse LSECs. LSEC cultures were freshly prepared from C57Bl/6JRj mouse liver. We first examined dose- and time-dependent effects of two dynamin-inhibitors, dynasore and MitMAB, on cell viability, morphology, and endocytosis of model ligands via different LSEC scavenger receptors to establish a protocol for dynamin-inhibition studies in these primary cells. LSECs were challenged with MuHV-1 (MOI 0.2) ± dynamin inhibitors for 1h, then without inhibitors and virus for 11h, and nuclear expression of MuHV-1 immediate early antigen (IE1) measured by immune fluorescence. MuHV-1 efficiently infected LSECs in vitro. Infection was significantly and independently inhibited by dynasore and MitMAB, which block dynamin function via different mechanisms, suggesting that initial steps of MuHV-1 infection is dynamin-dependent in LSECs. Infection was also reduced in the presence of monensin which inhibits acidification of endosomes. Furthermore, competitive binding studies with a neuropilin-1 antibody blocked LSEC infection. This suggests that MuHV-1 infection in mouse LSECs involves virus binding to neuropilin-1 and occurs via endocytosis.

Decellularization of the Human Liver to Generate Native Extracellular Matrix for Use in Automated Functional Assays with Stellate Cells.

With the incidence of liver disease on the rise globally, increasing numbers of patients are presenting with advanced hepatic fibrosis and significant mortality risk. The demand far outstrips possible transplantation capacities, and thus there is an intense drive to develop new pharmacological therapies that stall or reverse liver scarring. Recent late-stage failures of lead compounds have highlighted the challenges of resolving fibrosis, which has developed and stabilized over many years and varies in nature and composition from individual to individual. Hence, preclinical tools are being developed in both the hepatology and tissue engineering communities to elucidate the nature, composition, and cellular interactions of the hepatic extracellular niche in health and disease. In this protocol, we describe strategies for decellularizing cirrhotic and healthy human liver specimens and show how these can be used in simple functional assays to detect the impact on stellate cell function. Our simple, small-scale approach is translatable to diverse lab settings and generates cell-free materials which could be used for a variety of in vitro analyses as well as a scaffold for repopulating with key hepatic cell populations.

Are BMI and adipokines associated with asthma, atopy and lung function in young adults previously hospitalized for bronchiolitis?

BACKGROUND: Children hospitalized for bronchiolitis have increased risk of asthma and low lung function persisting into adulthood, but the underlying mechanisms are poorly understood. Body mass index (BMI) and adipokines are associated with respiratory morbidity. We aimed to investigate if associations between BMI and adipokines and the outcomes asthma, atopy, and lung function differed between young adults previously hospitalized for bronchiolitis and control subjects. METHODS: This sub study of a historical cohort enrolled 185 young adults previously hospitalized for bronchiolitis and 146 matched control subjects. Exposures (BMI and the adipokines: adiponectin, leptin, resistin, and ghrelin) and outcomes (asthma, atopy, and lung function) were measured cross-sectionally at 17-20 years of age. Associations were tested in regression models, and differences between the post-bronchiolitis- and control group were tested by including interaction terms. RESULTS: BMI was associated with asthma and lung function, but we did not find that the associations differed between the post-bronchiolitis- and control group. We also found some associations between adipokines and outcomes, but only associations between adiponectin and forced vital capacity (FVC) and between resistin and current asthma differed between the groups (p-value interaction term 0.027 and 0.040 respectively). Adiponectin tended to be positively associated with FVC in the post-bronchiolitis group, with an opposite tendency in the control group. Resistin was positively associated with current asthma only in the control group. CONCLUSION: The increased prevalence of asthma and impaired lung function observed in young adults previously hospitalized for bronchiolitis do not seem to be related to growth and fat metabolism.

Blood eosinophils during bronchiolitis: Associations with atopy, asthma and lung function in young adults.

AIM: To study if blood eosinophils during bronchiolitis were associated with atopy, asthma and lung function in young adults and if these associations differed between respiratory syncytial virus (RSV) bronchiolitis and non-RSV bronchiolitis. METHODS: This historical cohort enrolled 225 subjects. Blood eosinophils were measured during bronchiolitis in infancy, and the subjects were invited to a follow-up at 17-20 years of age including questionnaires for asthma and examinations of lung function and atopy. RESULTS: The level of eosinophils was positively associated with subsequent atopy in the unadjusted analysis, but not in the adjusted analysis, and not with asthma. There was a negative association between the level of eosinophils and forced vital capacity (FVC) (-0.11; -0.19, -0.02) and forced expiratory volume in first second (FEV1 ) (-0.12; -0.21, -0.03) (regression coefficient; 95% confidence interval). The non-RSV group had higher levels of eosinophils during bronchiolitis, but there was no interaction between the level of eosinophils and RSV status for any outcome. CONCLUSIONS: The level of eosinophils during bronchiolitis was negatively associated with lung function in young adult age, but we found no associations with atopy or asthma. These associations were not different after RSV bronchiolitis compared to non-RSV bronchiolitis.

Changes in the proteome and secretome of rat liver sinusoidal endothelial cells during early primary culture and effects of dexamethasone.

INTRODUCTION: Liver sinusoidal endothelial cells (LSECs) are specialized fenestrated scavenger endothelial cells involved in the elimination of modified plasma proteins and tissue turnover waste macromolecules from blood. LSECs also participate in liver immune responses. A challenge when studying LSEC biology is the rapid loss of the in vivo phenotype in culture. In this study, we have examined biological processes and pathways affected during early-stage primary culture of rat LSECs and checked for cell responses to the pro-inflammatory cytokine interleukin (IL)-1ß and the anti-inflammatory drug dexamethasone. METHODS: LSECs from male Sprague Dawley rats were cultured on type I collagen in 5% oxygen atmosphere in DMEM with serum-free supplements for 2 and 24 h. Quantitative proteomics using tandem mass tag technology was used to examine proteins in cells and supernatants. Validation was done with qPCR, ELISA, multiplex immunoassay, and caspase 3/7 assay. Cell ultrastructure was examined by scanning electron microscopy, and scavenger function by quantitative endocytosis assays. RESULTS: LSECs cultured for 24 h showed a characteristic pro-inflammatory phenotype both in the presence and absence of IL-1ß, with upregulation of cellular responses to cytokines and interferon-γ, cell-cell adhesion, and glycolysis, increased expression of fatty acid binding proteins (FABP4, FABP5), and downregulation of several membrane receptors (STAB1, STAB2, LYVE1, CLEC4G) and proteins in pyruvate metabolism, citric acid cycle, fatty acid elongation, amino acid metabolism, and oxidation-reduction processes. Dexamethasone inhibited apoptosis and improved LSEC viability in culture, repressed inflammatory and immune regulatory pathways and secretion of IL-1ß and IL-6, and further upregulated FABP4 and FABP5 compared to time-matched controls. The LSEC porosity and endocytic activity were reduced at 24 h both with and without dexamethasone but the dexamethasone-treated cells showed a less stressed phenotype. CONCLUSION: Rat LSECs become activated towards a pro-inflammatory phenotype during early culture. Dexamethasone represses LSEC activation, inhibits apoptosis, and improves cell viability.

Asthma, atopy and lung function in young adults after hospitalisation for bronchiolitis in infancy: impact of virus and sex.

BACKGROUND: Hospitalisation for bronchiolitis is a risk factor for asthma and impaired lung function during childhood, but outcomes in young adults are poorly described. Our primary aim was to study the prevalence of asthma and atopy, and lung function at 17-20 years of age after bronchiolitis in infancy and, secondarily, the impact of viral aetiology (respiratory syncytial virus (RSV) vs non-RSV) and sex on these outcomes. METHODS: This Norwegian cohort study enrolled 225 young adults hospitalised for bronchiolitis in infancy during 1996-2001 and 167 matched control subjects. The follow-up included questionnaires for asthma and examinations of lung function and atopy. Outcomes were analysed by mixed effects regressions. RESULTS: Current asthma was more frequent in the postbronchiolitis group versus the control group: 25.1% (95% CI 19.0% to 31.2%) vs 13.1% (95% CI 7.9% to 18.2%), but not atopy: 44.3% (95% CI 37.1% to 51.5%) vs 48.2% (95% CI 40.5% to 55.8%), adjusted predicted proportions (95% CIs). Asthma prevalence did not differ between the RSV group and the non-RSV group: 24.0% (95% CI 16.1% to 32.0%) vs 23.8% (95% CI 12.8% to 34.7%) nor between sexes. Forced expiratory volume in 1 s (FEV1), the ratio FEV1/forced vital capacity (FVC), and forced expiratory flow between 25% and 75% of FVC, were lower in the postbronchiolitis group. CONCLUSION: Young adults hospitalised for bronchiolitis had higher prevalence of asthma, but not atopy, and a more obstructive lung function pattern than control subjects. The asthma prevalence was high after both RSV bronchiolitis and non-RSV bronchiolitis, and there was no difference between sexes. Bronchiolitis in infancy is associated with respiratory morbidity persisting into young adulthood.

Autofluorescence in freshly isolated adult human liver sinusoidal cells.

Autofluorescent granules of various sizes were observed in primary human liver endothelial cells (LSECs) upon laser irradiation using a wide range of wavelengths. Autofluorescence was detected in LAMP-1 positive vesicles, suggesting lysosomal location. Confocal imaging of freshly prepared cultures and imaging flow cytometry of non-cultured cells revealed fluorescence in all channels used. Treatment with a lipofuscin autofluorescence quencher reduced autofluorescence, most efficiently in the near UV-area. These results, combined with the knowledge of the very active blood clearance function of LSECs support the notion that lysosomally located autofluorescent material reflected accumulation of lipofuscin in the intact liver. These results illustrate the importance of careful selection of fluorophores, especially when labelling of live cells where the quencher is not compatible.

The Scavenger Function of Liver Sinusoidal Endothelial Cells in Health and Disease.

The aim of this review is to give an outline of the blood clearance function of the liver sinusoidal endothelial cells (LSECs) in health and disease. Lining the hundreds of millions of hepatic sinusoids in the human liver the LSECs are perfectly located to survey the constituents of the blood. These cells are equipped with high-affinity receptors and an intracellular vesicle transport apparatus, enabling a remarkably efficient machinery for removal of large molecules and nanoparticles from the blood, thus contributing importantly to maintain blood and tissue homeostasis. We describe here central aspects of LSEC signature receptors that enable the cells to recognize and internalize blood-borne waste macromolecules at great speed and high capacity. Notably, this blood clearance system is a silent process, in the sense that it usually neither requires or elicits cell activation or immune responses. Most of our knowledge about LSECs arises from studies in animals, of which mouse and rat make up the great majority, and some species differences relevant for extrapolating from animal models to human are discussed. In the last part of the review, we discuss comparative aspects of the LSEC scavenger functions and specialized scavenger endothelial cells (SECs) in other vascular beds and in different vertebrate classes. In conclusion, the activity of LSECs and other SECs prevent exposure of a great number of waste products to the immune system, and molecules with noxious biological activities are effectively "silenced" by the rapid clearance in LSECs. An undesired consequence of this avid scavenging system is unwanted uptake of nanomedicines and biologics in the cells. As the development of this new generation of therapeutics evolves, there will be a sharp increase in the need to understand the clearance function of LSECs in health and disease. There is still a significant knowledge gap in how the LSEC clearance function is affected in liver disease.

The efficacy of physiotherapeutic intervention with biofeedback assisted pelvic floor muscle training in children with dysfunctional voiding.

INTRODUCTION: Dysfunctional voiding (DV) in children is a common issue, which can be found in up to 30% of children with wetting problems. Biofeedback assisted pelvic floor muscle training (PFMT) is an established nonpharmacological method to treat DV. The aim of the present study was to evaluate the efficacy of physiotherapeutic intervention with biofeedback assisted PFMT in children with DV. STUDY DESIGN: Children referred with DV, unresponsive to standard urotherapy were included in this study. All children underwent biofeedback assisted PFMT sessions with a physiotherapist. Uroflowmetries and measurements of post-void residual (PVR) urine were performed before and after the treatment, and the following parameters were registered; daytime incontinence (DI), nocturnal enuresis (NE), constipation, faecal incontinence (FI), and recurrent urinary tract infections (UTI). Other concomitant treatments were noted. The primary outcomes were the resolution of DV evaluated by uroflow curve configuration and PVR. Secondary outcomes were the resolution of DI, NE and the reduction of recurrent UTIs. RESULTS: Forty-six children (mean age 9.6 ± 2.4 years, 38 girls) were included in the analysis. The median period of treatment was 9.0 ± 8.5 months (2-9 visits). Twenty-seven (59%) children responded to treatment according to one or both primary outcomes; uroflow configuration (50%) and PVR (28%). DI resolved in 12 (26%) children and 27 of the 32 children, who prior to the treatment had recurrent UTIs experienced no UTIs during the follow up period. The use of anticholinergics was a significant negative predictor for response to treatment. We found that almost half of the responders (48%) reached effect prior to the fourth visit. DISCUSSION: Biofeedback assisted PFMT can improve the symptoms in children with DV. When comparing to existing literature we find a less pronounced effect of the intervention. A possible explanation may be that the children enrolled in this study were recruited from a tertiary referral centre and were all refractory to standard urotherapy. Moreover, the difference in patient characteristics and treatment protocols between different studies make direct comparisons of efficacy difficult. CONCLUSION: Physiotherapeutic intervention with biofeedback assisted PFMT seems to lead to better uroflow patterns in approximately 60% of cases in DV improving the uroflow curves and PVR, however improvement in uroflowmetry patterns is not necessarily reflected in the resolution of incontinence or UT symptoms. The use of anticholinergics seems to be a negative predictor for response to treatment.

Transcriptome and proteome profiling reveal complementary scavenger and immune features of rat liver sinusoidal endothelial cells and liver macrophages.

BACKGROUND: Liver sinusoidal endothelial cells (LSECs) and Kupffer cells (KCs; liver resident macrophages) form the body's most effective scavenger cell system for the removal of harmful blood-borne substances, ranging from modified self-proteins to pathogens and xenobiotics. Controversies in the literature regarding the LSEC phenotype pose a challenge when determining distinct functionalities of KCs and LSECs. This may be due to overlapping functions of the two cells, insufficient purification and/or identification of the cells, rapid dedifferentiation of LSECs in vitro, or species differences. We therefore characterized and quantitatively compared expressed gene products of freshly isolated, highly pure LSECs (fenestrated SE-1/FcγRIIb2+) and KCs (CD11b/c+) from Sprague Dawley, Crl:CD (SD), male rats using high throughput mRNA-sequencing and label-free proteomics. RESULTS: We observed a robust correlation between the proteomes and transcriptomes of the two cell types. Integrative analysis of the global molecular profile demonstrated the immunological aspects of LSECs. The constitutive expression of several immune genes and corresponding proteins of LSECs bore some resemblance with the expression in macrophages. LSECs and KCs both expressed high levels of scavenger receptors (SR) and C-type lectins. Equivalent expression of SR-A1 (Msr1), mannose receptor (Mrc1), SR-B1 (Scarb1), and SR-B3 (Scarb2) suggested functional similarity between the two cell types, while functional distinction between the cells was evidenced by LSEC-specific expression of the SRs stabilin-1 (Stab1) and stabilin-2 (Stab2), and the C-type lectins LSECtin (Clec4g) and DC-SIGNR (Clec4m). Many immune regulatory factors were differentially expressed in LSECs and KCs, with one cell predominantly expressing a specific cytokine/chemokine and the other cell the cognate receptor, illustrating the complex cytokine milieu of the sinusoids. Both cells expressed genes and proteins involved in antigen processing and presentation, and lymphocyte co-stimulation. CONCLUSIONS: Our findings support complementary and partly overlapping scavenging and immune functions of LSECs and KCs. This highlights the importance of including LSECs in studies of liver immunity, and liver clearance and toxicity of large molecule drugs and nano-formulations.

Ética de la Salud Pública: propuesta sobre los principios fundamentales que guían las responsabilidades éticas del estado en el contexto pandemia COVID-19 / Proposal on the principles that should guide the ethical responsibilities of the state during the COVID-19 pandemic

On March 11, 2020, the World Health Organization (WHO) stated that the number of cases of COVID-19 multiplied by 13 outside China, with a threefold increase in the number of affected countries. The WHO expressed its concern about the alarming levels of spread and severity of the outbreak, declaring the pandemic. This pandemic context is generating a social pact that seeks to ensure collective protection over individual freedoms. To meet the challenge, Governments must make decisions based on the principles that govern the State- These should consider the differences and particularities of those affected, without diverting attention from collective social protection. The following is a proposal on the ethical principles that should guide a State that makes decisions in public health emergencies.

Ocular Histopathological Findings in Semi-Domesticated Eurasian Tundra Reindeer (Rangifer tarandus tarandus) with Infectious Keratoconjunctivitis after Experimental Inoculation with Cervid Herpesvirus 2.

Infectious keratoconjunctivitis (IKC) is a common transmissible ocular disease in semi-domesticated Eurasian tundra reindeer (Rangifer tarandus tarandus). In large outbreaks, IKC may affect tens of animals in a herd, with the most severe cases often requiring euthanasia due to the destruction of the affected eyes and permanent blindness. An experimental inoculation with cervid herpesvirus 2 (CvHV2), alone or in combination with Moraxella bovoculi, demonstrated that CvHV2 has the ability to cause clinical signs of IKC in previously unexposed reindeer. Tissues collected from upper and lower eyelids, lacrimal gland and cornea, were processed for light and transmission electron microscopy. Histopathological analysis of the eyes inoculated with CvHV2 showed widespread and severe pathological findings. Mucosal tissues from these eyes showed fibrinous and purulent exudates, hyperemia, hemorrhages, necrosis, vascular thrombosis, vascular necrosis, infiltration of mononuclear cells and neutrophils, and lymphoid follicle reaction, which matches the described histopathology of IKC in reindeer. Characteristic alpha-herpesvirus particles matching the size and morphology of CvHV2 were identified by transmission electron microscopy in the conjunctival tissue. The quantification of viral particles by qPCR revealed high copy numbers of viral DNA in all CvHV2 inoculated eyes, but also in the non-inoculated eyes of the same animals. The histopathology of eye tissues obtained from the CvHV2 inoculated reindeer and the lack of inflammation from bacterial infection, together with the detection of CvHV2 DNA in swabs from the inoculated and non-inoculated eyes of the same animals, verified that CvHV2 was the primary cause of the observed histopathological changes.

Aportaciones de una práctica de promoción de salud comunitaria a la formación profesional de estudiantes de medicina de la Universidad de Chile / Contributions of a health promotion practice for the professional training of medical students at the University of Chile

INTRODUCCIÓN: La promoción de salud es esencial dentro de un sistema de salud basado en la atención primaria. Pese a ello, prevalece una escasa integración de las acciones de promoción de salud, tanto en la formación como en el desempeño profesional de médicos generalistas. OBJETIVO: Describir las aportaciones de una práctica de promoción de salud en la formación médica, desde lo expresado por estudiantes de medicina durante su internado rural. Sujetos y métodos. Estudio descriptivo cualitativo basado en informes sobre acciones de promoción de salud realizadas por internos de medicina de la Universidad de Chile, en 2016-2018. Se realizó un análisis del contenido de las narrativas para identificar inductivamente categorías descriptivas de las aportaciones. RESULTADOS: Se identificaron nueve categorías de aportaciones, cinco de ellas relacionadas con el diseño e implementación de actividades de promoción de salud comunitaria (reconocimiento de características de la audiencia; adaptación a la audiencia; autorreconocimiento de limitaciones, dificultades y manejo de incertidumbre; valoración de saberes comunitarios; satisfacción con resultados) y cuatro relacionadas con el reconocimiento del papel del médico en la práctica comunitaria (comprensión del contexto local; reflexión crítica sobre actores y roles institucionales; deficiencias en la formación médica; visión de las actividades y rol del médico). CONCLUSIONES: La práctica de promoción de salud comunitaria constituye un espacio de aprendizajes en torno a los grupos sociales, de adaptación a las condiciones locales y de refuerzo del papel del médico, que son percibidos como aportaciones a la formación médica

INTRODUCTION: Health promotion represents a key element of a primary-care based health system. Nevertheless, poor integration of the health promotion actions still prevails in the undergraduate training and the professional performance of generalist practitioners. AIM: To describe the contributions of a health promotion practice in the undergraduate medical training, as expressed by medical students during their internship in a rural area. Subjects and methods. Qualitative descriptive study, based on the University of Chile medical student's reports of their health promotion activities developed during 2016 to 2018. Narrative content analysis was performed in order to inductively identify descriptive categories for these contributions. RESULTS: Nine categories of contributions were identified; five of them are related to the design and implementation of health promotion activities at community level (acknowledgment of audience's characteristics; adaptation to the audience; self-awareness of limitations, difficulties and uncertainty management; appreciation of the community wisdom and knowledge; satisfaction with the activity results), and four further categories refer to the recognition of the physician's role in the community (local context assessment; critical appraisal of institutional roles and actors; deficiencies in previous medical training; perspectives on community work and the physician's role in that context). CONCLUSIONS: Community-based health promotion activities are important scenarios for learning about social groups, adaptation to local conditions and strengthening the physician's role. These are perceived as contributions to the under-graduate training of medical professionals

Half of children with recurrent or chronic wet cough before three years of age were symptom-free by age seven.

AIM: We aimed to study the natural course of recurrent episodic and chronic wet cough in preschool children, the proportion and age of resolution, and risk factors for persistent symptoms. METHODS: Parents of children with recurrent or chronic wet cough who had attended the outpatient clinic before the age of three years during 2010-2013 at Stavanger University Hospital, Norway, answered a questionnaire regarding clinical symptoms and current medication at a follow-up in 2017-2018. RESULTS: We invited 840 children to participate, and parents consented for 348 (41.4%) of the children. At the first outpatient visit, 171 children (58.8%) had recurrent episodic and 120 (41.2%) had chronic wet cough. At follow-up at a median age of 82 months, 57.0% in both groups were symptom-free, and 9.4% with episodic cough and 13.3% with chronic cough had more than mild symptoms. During the last 12 months prior to the survey, 27.2% with episodic cough and 18.6% with chronic cough had used inhaled corticosteroids. CONCLUSION: Half of the preschool children with recurrent episodic or chronic wet cough outgrew their symptoms by the median age of seven years, but one in four still used inhaled corticosteroids.

Liver sinusoidal endothelial cells contribute to the uptake and degradation of entero bacterial viruses.

The liver is constantly exposed to dietary antigens, viruses, and bacterial products with inflammatory potential. For decades cellular uptake of virus has been studied in connection with infection, while the few studies designed to look into clearance mechanisms focused mainly on the role of macrophages. In recent years, attention has been directed towards the liver sinusoidal endothelial cells (LSECs), which play a central role in liver innate immunity by their ability to scavenge pathogen- and damage-associated molecular patterns. Every day our bodies are exposed to billions of gut-derived pathogens which must be efficiently removed from the circulation to prevent inflammatory and/or immune reactions in other vascular beds. Here, we have used GFP-labelled Enterobacteria phage T4 (GFP-T4-phage) as a model virus to study the viral scavenging function and metabolism in LSECs. The uptake of GFP-T4-phages was followed in real-time using deconvolution microscopy, and LSEC identity confirmed by visualization of fenestrae using structured illumination microscopy. By combining these imaging modalities with quantitative uptake and inhibition studies of radiolabelled GFP-T4-phages, we demonstrate that the bacteriophages are effectively degraded in the lysosomal compartment. Due to their high ability to take up and degrade circulating bacteriophages the LSECs may act as a primary anti-viral defence mechanism.

Lung function and bronchial hyper-reactivity from 11 to 18 years in children with bronchiolitis in infancy.

BACKGROUND: Various trajectories for lung function and bronchial hyper-reactivity (BHR) from early childhood to adulthood are described, including puberty as a period with excessive lung growth. Bronchiolitis in infancy may be associated with increased risk of developing chronic obstructive pulmonary disease, but the development of respiratory patterns during puberty is poorly characterized for these children. We aimed to study the development and trajectories of lung function and BHR from 11 to 18 years of age in children hospitalized for bronchiolitis in infancy. METHODS: Infants hospitalized for bronchiolitis at the University Hospitals in Stavanger and Bergen, Norway, during 1997-1998, and an age-matched control group, were included in a longitudinal follow-up study and examined at 11 and 18 years of age with spirometry and methacholine provocation test (MPT). The MPT data were managed as dose-response slope (DRS) in the statistical analyses. Changes in lung function and DRS from 11 to 18 years of age were analyzed by generalized estimating equations, including interaction terms. RESULTS: z-scores for forced vital capacity (FVC), forced expiratory volume in first second (FEV1 ), FEV1 /FVC ratio, and DRS were not different from 11 to 18 years of age in both the post-bronchiolitis and the control group. The trajectories from 11 to 18 years did not differ between the two groups. BHR at age 11 was independently associated with asthma at age 18. CONCLUSION: Children hospitalized for bronchiolitis had stable predicted lung function and BHR from 11 to 18 years of age. The lung function trajectories were not different from controls.