A comprehensive approach to identify challenges for clinical reasoning development in undergraduate dental students and their potential solutions.

INTRODUCTION: Clinical reasoning is a core competence in health professions that impacts the ability to solve patients' health problems. Due to its relevance, it is necessary to identify difficulties arising from different sources that affect clinical reasoning development in students. The aim of this study was to explore a comprehensive approach to identify challenges for clinical reasoning development in undergraduate dental students and their potential solutions. METHODS: Mixed methods were used in four stages: (1) students and clinical teachers focus groups to identify challenges to clinical reasoning development; (2) literature review to explore potential solutions for these challenges; (3) Delphi technique for teacher consensus on pertinence and feasibility of solutions (1-5 scale); and (4) teachers' self-perception of their ability to implement the solutions. RESULTS: Three categories and seven subcategories of challenges were identified: (I) educational context factors influencing the clinical reasoning process; (II) teacher's role in clinical reasoning development; and (III) student factors influencing the clinical reasoning process. From 134 publications identified, 53 were selected for review, resulting in 10 potential solutions. Through two Delphi rounds, teachers rated the potential solutions very highly in terms of relevance (4.50-4.85) and feasibility (3.50-4.29). Finally, a prioritisation ranking of these solutions was generated using their scores for relevance, feasibility, and teachers' self-perception of their ability to implement them. CONCLUSIONS: The present comprehensive approach identified challenges for clinical reasoning development in dental students and their potential solutions, perceived as relevant and feasible by teachers, requiring further research and follow-up actions to address them.

Heme oxygenase-1 in protozoan infections: A tale of resistance and disease tolerance.

Heme oxygenase (HO-1) mediates the enzymatic cleavage of heme, a molecule with proinflammatory and prooxidant properties. HO-1 activity deeply impacts host capacity to tolerate infection through reduction of tissue damage or affecting resistance, the ability of the host to control pathogen loads. In this Review, we will discuss the contribution of HO-1 in different and complex protozoan infections, such as malaria, leishmaniasis, Chagas disease, and toxoplasmosis. The complexity of these infections and the pleiotropic effects of HO-1 constitute an interesting area of study and an opportunity for drug development.

Mitochondrial Reactive Oxygen Species Participate in Signaling Triggered by Heme in Macrophages and upon Hemolysis.

Hemolysis causes an increase of intravascular heme, oxidative damage, and inflammation in which macrophages play a critical role. In these cells, heme can act as a prototypical damage-associated molecular pattern, inducing TLR4-dependent cytokine production through the MyD88 pathway, independently of TRIF. Heme promotes reactive oxygen species (ROS) generation independently of TLR4. ROS and TNF production contribute to heme-induced necroptosis and inflammasome activation; however, the role of ROS in proinflammatory signaling and cytokine production remains unknown. In this study, we demonstrate that heme activates at least three signaling pathways that contribute to a robust MAPK phosphorylation and cytokine expression in mouse macrophages. Although heme did not induce a detectable Myddosome formation, the TLR4/MyD88 axis was important for phosphorylation of p38 and secretion of cytokines. ROS generation and spleen tyrosine kinase (Syk) activation induced by heme were critical for most proinflammatory signaling pathways, as the antioxidant N-acetyl-l-cysteine and a Syk inhibitor differentially blocked heme-induced ROS, MAPK phosphorylation, and cytokine production in macrophages. Early generated mitochondrial ROS induced by heme was Syk dependent, selectively promoted the phosphorylation of ERK1/2 without affecting JNK or p38, and contributed to CXCL1 and TNF production. Finally, lethality caused by sterile hemolysis in mice required TLR4, TNFR1, and mitochondrial ROS, supporting the rationale to target these pathways to mitigate tissue damage of hemolytic disorders.

ROS and Trypanosoma cruzi: Fuel to infection, poison to the heart.

The activation of macrophage respiratory burst in response to infection with Trypanosoma cruzi inflicts oxidative damage to the host's tissues. For decades, the role of reactive oxygen species (ROS) in the elimination of T. cruzi was taken for granted, but recent evidence suggests parasite growth is stimulated in oxidative environments. It is still a matter of debate whether indeed oxidative environments provide ideal conditions (e.g., iron availability in macrophages) for T. cruzi growth and whether indeed ROS signals directly to stimulate growth. Nitric oxide (NO) and ROS combine to form peroxynitrite, participating in the killing of phagocytosed parasites by activated macrophages. In response to infection, mitochondrial ROS are produced by cardiomyocytes. They contribute to oxidative damage that persists at the chronic stage of infection and is involved in functional impairment of the heart. In this review, we discuss how oxidative stress helps parasite growth during the acute stage and how it participates in the development of cardiomyopathy at the chronic stage.

Cardiac arrhythmias after renal I/R depend on IL-1ß.

AIMS: Cardiac arrhythmias are one of the most important remote complications after kidney injury. Renal ischemia reperfusion (I/R) is a major cause of acute renal injury predisposing to several remote dysfunctions, including cardiac electrical disturbance. Since IL-1ß production dependent on NLRP3 represents a link between tissue malfunctioning and cardiac arrhythmias, here we tested the hypothesis that longer ventricular repolarization and arrhythmias after renal I/R depend on this innate immunity sensor. METHODS AND RESULTS: Nlrp3-/- and Casp1-/- mice reacted to renal I/R with no increase in plasma IL-1ß, different from WT (wild-type) I/R. A prolonged QJ interval and an increased susceptibility to ventricular arrhythmias were found after I/R compared to Sham controls in wild-type mice at 15 days post-perfusion, but not in Nlrp3-/- or CASP1-/- I/R, indicating that the absence of NLRP3 or CASP1 totally prevented longer QJ interval after renal I/R. In contrast with WT mice, we found no renal atrophy and no renal dysfunction in Nlrp3-/- and Casp1-/- mice after renal I/R. Depletion of macrophages in vivo after I/R and a day before IL-1ß peak (at 7 days post-perfusion) totally prevented prolongation of QJ interval, suggesting that macrophages might participate as sensors of tissue injury. Moreover, treatment of I/R-WT mice with IL-1r antagonist (IL-1ra) from 8 to 15 days post perfusion did not interfere with renal function, but reversed QJ prolongation, prevented the increase in susceptibility to ventricular arrhythmias and rescued a close to normal duration and amplitude of calcium transient. CONCLUSION: Taken together, these results corroborate the hypothesis that IL-1ß is produced after sensing renal injury through NRLP3-CASP1, and IL-1ß on its turn triggers longer ventricular repolarization and increase susceptibility to cardiac arrhythmias. Still, they offer a therapeutic approach to treat cardiac arrhythmias that arise after renal I/R.

Resveratrol Reverses Functional Chagas Heart Disease in Mice.

Chronic chagasic cardiomyopathy (CCC) develops years after acute infection by Trypanosoma cruzi and does not improve after trypanocidal therapy, despite reduction of parasite burden. During disease, the heart undergoes oxidative stress, a potential causative factor for arrhythmias and contractile dysfunction. Here we tested whether antioxidants/ cardioprotective drugs could improve cardiac function in established Chagas heart disease. We chose a model that resembles B1-B2 stage of human CCC, treated mice with resveratrol and performed electrocardiography and echocardiography studies. Resveratrol reduced the prolonged PR and QTc intervals, increased heart rates and reversed sinus arrhythmia, atrial and atrioventricular conduction disorders; restored a normal left ventricular ejection fraction, improved stroke volume and cardiac output. Resveratrol activated the AMPK-pathway and reduced both ROS production and heart parasite burden, without interfering with vascularization or myocarditis intensity. Resveratrol was even capable of improving heart function of infected mice when treatment was started late after infection, while trypanocidal drug benznidazole failed. We attempted to mimic resveratrol's actions using metformin (AMPK-activator) or tempol (SOD-mimetic). Metformin and tempol mimicked the beneficial effects of resveratrol on heart function and decreased lipid peroxidation, but did not alter parasite burden. These results indicate that AMPK activation and ROS neutralization are key strategies to induce tolerance to Chagas heart disease. Despite all tissue damage observed in established Chagas heart disease, we found that a physiological dysfunction can still be reversed by treatment with resveratrol, metformin and tempol, resulting in improved heart function and representing a starting point to develop innovative therapies in CCC.

Silymarin reduces profibrogenic cytokines and reverses hepatic fibrosis in chronic murine schistosomiasis.

In chronic schistosomiasis, hepatic fibrosis is linked to the portal hypertension that causes morbidity in Schistosoma mansoni infection. Silymarin (SIL) is a hepatoprotective and antioxidant medicament largely prescribed against liver diseases that has previously been shown to prevent fibrosis during acute murine schistosomiasis. Here we employed silymarin to try to reverse established hepatic fibrosis in chronic schistosomiasis. Silymarin or vehicle was administered to BALB/c mice every 48 h, starting on the 40th (80 days of treatment), 70th (50 days), or 110th (10 days) day postinfection (dpi). All mice were sacrificed and analyzed at 120 dpi. Treatment with silymarin reduced liver weight and granuloma sizes, reduced the increase in alanine aminotransferase and aspartate aminotransferase levels, and reduced the established hepatic fibrosis (assessed by hydroxyproline contents and picrosirius staining). Treatment with silymarin also reduced the levels of interleukin-13 (IL-13) in serum and increased the gamma interferon (IFN-γ)/IL-13 ratio. There was a linear correlation between IL-13 levels in serum and hydroxyproline hepatic content in both infected untreated and SIL-treated mice, with decreased IL-13 levels corresponding to decreased hydroxyproline hepatic contents. Treatment with either SIL or N-acetylcysteine reduced both proliferation of fibroblast cell lines and basal/IL-13-induced production of collagen I, indicating that besides inhibiting IL-13 production during infection, SIL antioxidant properties most likely contribute to inhibition of collagen production downstream of IL-13. These results show that silymarin interferes with fibrogenic cytokines, reduces established fibrosis, and inhibits downstream effects of IL-13 on fibrogenesis, indicating the drug as a safe and cheap treatment to liver fibrotic disease in schistosomiasis.

Perforated duodenal ulcer after Roux-en-Y gastric bypass: an unusual complication.

Summary: Bariatric surgery is increasingly being accepted as a viable treatment for managing the growing obesity epidemic. Roux-en-Y gastric bypass (RYGB) is one of the most commonly performed procedures. Perforated duodenal ulcer following RYGB is a rare condition with a low incidence. We report a case of a patient with a perforated duodenal ulcer post RYGB, and the surgical approach. A 66-year-old man with hypertension and a history of laparoscopic RYGB for class III obesity was admitted to the emergency department with severe epigastric pain radiating to the right side of his abdomen and right shoulder, associated with nausea and vomiting. Computed tomography (CT) showed intraperitoneal free fluid, a thickened wall of the duodenum and free air, duodenal perforation was suspected. The patient underwent exploratory laparoscopy that revealed a perforated duodenal ulcer that was closed with an absorbable barbed suture and omental patch. Perforated ulcers in excluded segments after RYGB are a rare entity with a challenging diagnosis, and clinicians should be aware of and have a low threshold for diagnostic laparoscopy. Learning points: Roux-en-Y gastric bypass (RYGB) is one of the most commonly performed procedures in bariatric surgery. Perforated ulcers in excluded segments after RYGB are a rare entity with a challenging diagnosis. The pathophysiology of this perforation is not clear, but several mechanisms have been proposed. Helicobacter pylori has been implicated. Clinicians should be aware and have a low threshold for diagnostic laparoscopy for a patient who has acute abdominal pain after RYGB, despite negative diagnostic measures.

Evaluation of the Influence of Geodimensional and Histological Parameters on the Need for Margin Widening in Breast Lesions Marked With Magnetic Seeds.

Objective: Breast cancer is an important topic worldwide, posing morbidity and mortality to women. Considerable efforts have been put in the early recognition of malignancy through different screening methods, such as mammography and ultrasound. The precise localization of infraclinical malignant lesions is key in surgical management and magnetic seeds gather particular interest for this purpose. As with other systems, a need for reintervention may be needed to obtain adequate surgical margins. This work evaluated the relation between the need for surgical reintervention in order to obtain negative margins and geodimensional and histological parameters. The main objective was the identification of parameters significantly associated with reintervention for margin widening. Materials and Methods: A retrospective analysis of 198 patients from a single centre was performed. The association between pre-defined geodimensional and histological parameters and the need for margin widening in infraclinical lesions marked with magnetic seed was evaluated. Results: Results showed that reintervention to widen margins was significantly higher in patients with ductal carcinoma in situ (DCIS) in the pre-operative biopsy when compared with invasive carcinoma (p = 0.03) in the bivariate analysis. No statistically significant differences were observed between the need for reintervention and lesion size (p = 0.197), breast quadrant location (p = 0.626) and distance of skin to lesion (p = 0.356). Conclusion: This work suggests that a more invasive margin clearance in lesions with a pre-operative DCIS diagnosis might obviate the need for reintervention to obtain negative margins. On the other hand, it is not necessary to be surgically more invasive in larger lesions, deeply located or that are present in a certain quadrant, since there are no significant differences regarding the need for reintervention.

MITIG.RA: study protocol of a tailored psychological intervention for managing fatigue in rheumatoid arthritis randomized controlled trial.

BACKGROUND: Despite remarkable medical advances in the treatment of rheumatoid arthritis (RA), a subset of patients fails to achieve complete clinical remission, as the Patient Global Assessment (PGA) of disease activity remains above 1, even after the inflammatory process is brought under control. This so-called state of 'PGA-near-remission' negatively impacts individuals' functioning and potentiates inadequate care. Fatigue is a distressing and disabling symptom frequently reported by patients in PGA-near-remission, and its management remains challenging. While classic cognitive-behavioural interventions show some benefits in managing fatigue, there is potential for improvement. Recently, contextual-cognitive behavioural therapies (CCBT), like mindfulness, acceptance, and compassion-based interventions, have shown promising results in fatigue-associated disorders and their determinants. This study primarily aims to examine the efficacy of the Compassion and Mindfulness Intervention for RA (MITIG.RA), a novel intervention combining different components of CCBT, compared to treatment-as-usual (TAU) in the management of RA-associated fatigue. Secondary aims involve exploring whether MITIG.RA produces changes in the perceived impact of disease, satisfaction with disease status, levels of depression, and emotion-regulation skills. METHODS: This is a single center, two-arm parallel randomized controlled trial. Patients will be screened for eligibility and willingness to participate and will be assessed and randomized to the experimental (MITIG.RA + TAU) or control condition (TAU) using computer randomization. MITIG.RA will be delivered by a certified psychologist and comprises eight sessions of 2 h, followed by two booster sessions. Outcomes will be assessed through validated self-report measures, including fatigue (primary outcome), perceived impact of disease, depressive symptoms, mindfulness, self-compassion, safety, and satisfaction (secondary outcomes). Assessment will take place at baseline, post-intervention, before the first and second booster sessions (weeks 12 and 20, respectively), and at 32 and 44 weeks after the interventions' beginning. DISCUSSION: We expect MITIG.RA to be effective in reducing levels of RA-associated fatigue. Secondarily, we hypothesize that the experimental group will show improvements in the overall perceived impact of disease, emotional distress, and emotion regulation skills. Our findings will contribute to determine the benefits of combining CCBT approaches for managing fatigue and associated distress in RA. TRIAL REGISTRATION: ClinicalTrials.gov NCT05389189. Registered on May 25, 2022.

Patient-Reported Outcomes and Experiences Assessment in Women with Breast Cancer: Portuguese Case Study.

In 2020, female breast cancer was the most commonly diagnosed cancer worldwide, representing the type of cancer with the highest incidence among women and the second most common cause of cancer death among women in all OECD countries. The conventional measures addressing the burden of breast cancer by measuring mortality, incidence, and survival do not entirely reflect the quality of life and patients experience when receiving breast cancer care. The main objective of this study is to capture patient-reported outcomes and experiences in women with breast cancer in Portugal using methods developed for international benchmarking purposes, such as the OECD Patient-reported Indicators Surveys. The study included 378 women with breast cancer, with the age distribution being 19.8% aged 15 to 49 years and 80.2% aged 50 years and over. The data collection procedure and analysis followed the "OECD Breast Cancer Patient Reported Outcomes Working Group" protocol, allowing subsequent comparability with data from other OECD member countries. Most women were satisfied with the treatment outcome regarding the shape of their lumpectomy breast when wearing a bra (96.1%) and with the equal size of both breasts (78.3%). Findings on the WHO QOL-BREF showed that women manifest a lower score in well-being when compared with the general population or populations living with chronic diseases. This study shows the feasibility of implementing and using patient-reported metrics (PROM and PREM) in breast cancer services in Portugal. Measuring PROMs and PREMs from Portuguese women receiving breast cancer care provides insightful evidence into the quality and value of cancer care.

IL-1ß is not critical to chronic heart dysfunction in mice with Chagas disease.

Long after Trypanosoma cruzi infection, 40% of individuals develop a progressive chronic chagasic cardiomyopathy (CCC), with systolic dysfunction and arrhythmias. Since we previously showed IL-1ß mediates the development of systolic dysfunction and cardiac arrhythmias in diabetes mellitus and cardiorenal syndrome, and IL-1ß remains elevated in Chagas disease patients, here we tested the role of IL-1ß in CCC using a mouse model. Mice deficient in IL-1R expression (Il-1r-/- ) survived acute T. cruzi infection with greater parasitemia than controls but did not lose weight as wild-type (WT) did. At the chronic stage, WT presented prolonged ventricular repolarization intervals (QJ), while Il-1r-/- presented intervals like noninfected controls. Infected Il-1r-/- and WT did not differ in stroke volume (SV), the incidence of cardiac arrhythmias on electrocardiography (EKG), whole heart action potential duration (APD), or the incidence of triggered activity after S1-S2 protocol, which is a measure of susceptibility to cardiac arrhythmias. We also treated chronically infected WT mice with an IL-1R antagonist, anakinra. Treatment shortened the QJ interval but did not improve the SV or the incidence of cardiac arrhythmias on EKG. Anakinra failed to reduce triggered activity following the electrical extra-stimulation protocol. In conclusion, the absence of functional IL-1ß/IL-1R signaling did not prevent or reverse the decrease of SV or the incidence of cardiac arrhythmias induced by chronic T. cruzi infection, implying this is not a critical mechanism in generating or maintaining CCC. Since similar cardiac abnormalities were previously credited to IL-1ß signaling, ruling out this mechanism is important to discourage further attempts of IL-1ß blockade as a therapeutical measure.

Heme amplifies the innate immune response to microbial molecules through spleen tyrosine kinase (Syk)-dependent reactive oxygen species generation.

Infectious diseases that cause hemolysis are among the most threatening human diseases, because of severity and/or global distribution. In these conditions, hemeproteins and heme are released, but whether heme affects the inflammatory response to microorganism molecules remains to be characterized. Here, we show that heme increased the lethality and cytokine secretion induced by LPS in vivo and enhanced the secretion of cytokines by macrophages stimulated with various agonists of innate immune receptors. Activation of nuclear factor κB (NF-κB) and MAPKs and the generation of reactive oxygen species were essential to the increase in cytokine production induced by heme plus LPS. This synergistic effect of heme and LPS was blocked by a selective inhibitor of spleen tyrosine kinase (Syk) and was abrogated in dendritic cells deficient in Syk. Moreover, inhibition of Syk and the downstream molecules PKC and PI3K reduced the reactive oxygen species generation by heme. Our results highlight a mechanism by which heme amplifies the secretion of cytokines triggered by microbial molecule activation and indicates possible pathways for therapeutic intervention during hemolytic infectious diseases.

Chloroquine inhibits pro-inflammatory effects of heme on macrophages and invivo.

BACKGROUND: Chloroquine has been used successfully to treat Malaria, including by chloroquine-resistant Plasmodium sp., indicating that it has effects on disease itself. Since heme has inflammatory effects and contributes to the pathogenesis of hemolytic diseases, we hypothesize that the anti-inflammatory effect of chloroquine is partially due to its inhibitory effect on heme-induced macrophage activation and on inflammatory tissue damage. METHODS: Bone marrow derived macrophages (BMDMs) were incubated with chloroquine before stimulation with heme, in different conditions, to evaluate cytokines secretion, ROS production, mitogen activated protein kinases (MAPK) or spleen tyrosine kinase (Syk) activation, alone or combined with LPS. The effects of chloroquine upon heme inflammation were also evaluated in vivo, through simultaneous i.p. injection of LPS and heme, intratracheal instillation of Poly-IC followed by heme injection, and in a rhabdomyolysis model. RESULTS: Chloroquine inhibited TNF secretion, mitochondrial ROS production, MAPK, and Syk activation induced by heme. Inhibition of TNF production could be mimicked by zinc ionophore quercetin, but not by primaquine, a chloroquine analog with low affinity for heme. IL-6 and IL-1ß secretions induced by heme in the presence of PRRs agonists were inhibited by chloroquine, but not by calcium chelator BAPTA or inhibitor of endosomal acidification concamycin B. Chloroquine also protected mice from heme inflammatory effects in vivo, inhibiting lethal synergism with PRR agonists, lung pathology caused by heme injection after intratracheal instillation of Poly-IC, and delaying death after rhabdomyolisis. CONCLUSION: Our data indicate that chloroquine might be used as a supportive therapy to control heme-induced deleterious inflammation in different hemolytic diseases.

Macrophage migration inhibitory factor is critical to interleukin-5-driven eosinophilopoiesis and tissue eosinophilia triggered by Schistosoma mansoni infection.

Macrophage migration inhibitory factor (MIF) participates in the pathogenesis of inflammatory diseases, including asthma, in which it enhances airway hypersensitivity and tissue eosinophilia. Herein, we investigated the role of MIF in eosinophilopoiesis and tissue eosinophilia using Schistosoma mansoni infection. MIF-deficient (Mif(-/-)) mice had similar numbers of adult worms, eggs, and granulomas compared to wild-type mice, but the size of granulomas was strikingly reduced due to smaller numbers of eosinophils. MIF did not affect the acquired response to infection, as Mif(-/-) mice produced normal amounts of Th2 cytokines and IgE. Nevertheless, recombinant MIF (rMIF) behaved as a chemoattractant for eosinophils, what could partially explain the reduced eosinophilia in infected Mif(-/-) mice. Moreover, the percentage of eosinophils was reduced in bone marrows of Mif(-/-) mice chronically infected with S. mansoni compared to wild type. Mif(-/-) had impaired eosinophilopoiesis in response to interleukin (IL)-5 and addition of rMIF to bone marrow cultures from IL-5 transgenic mice enhanced the generation of eosinophils. In the absence of MIF, eosinophil precursors were unable to survive the IL-5-supplemented cell culture, and were ingested by macrophages. Treatment with pancaspase inhibitor z-VAD or rMIF promoted the survival of eosinophil progenitors. Together, these results indicate that MIF participates in IL-5-driven maturation of eosinophils and in tissue eosinophilia associated with S. mansoni infection.

Silymarin treatment reduces granuloma and hepatic fibrosis in experimental schistosomiasis.

The schistosomiasis is a parasitic infection with relevant social impact and an important health problem in many countries around world. The pathology of this infection is characterized by a granulomatous reaction around parasite eggs and by hepatic fibrosis. Silymarin, a complex compound isolated from Silybum marianum (L.) Gaertner, have been described as hepatoprotective, antioxidant, antifibrotic, immunomodulator, and anti-neoplastic agent. Some of these capacities could potentially protect against pathology in schistosomiasis. Herein, we evaluated the effects of silymarin on parasite burden, granuloma sizes, and liver fibrosis, which are associated with severity and morbidity of this disease. BALB/c mice treated intraperitoneally with 10, 20, or 25 doses of silymarin (10 mg kg(-1)) suspended in carboxymethylcellulose were analyzed at 55 days post-infection. Silymarin (1) did not affect parasite oviposition capacity; (2) reduced granulomatous peri-ovular reaction in the liver, and (3) decreased hepatic fibrosis in this infection. Taken together, these data suggest that treatment with silymarin at acute phase of schistosomiasis may result in a mild course of murine schistosomiasis and can be a promising complementary treatment reverting sequelae of this infection.

The Role of MIF on Eosinophil Biology and Eosinophilic Inflammation.

Macrophage migration inhibitory factor (MIF) is an inflammatory cytokine that participates in innate and adaptive immune responses. MIF contributes to the resistance against infection agents, but also to the cellular and tissue damage in infectious, autoimmune, and allergic diseases. In the past years, several studies demonstrated a critical role for MIF in the pathogenesis of type-2-mediated inflammation, including allergy and helminth infection. Atopic patients have increased MIF amounts in affected tissues, mainly produced by immune cells such as macrophages, Th2 cells, and eosinophils. Increased MIF mRNA and protein are found in activated Th2 cells, while eosinophils stock pre-formed MIF protein and secrete high amounts of MIF upon stimulation. In mouse models of allergic asthma, the lack of MIF causes an almost complete abrogation of the cardinal signs of the disease including mucus secretion, eosinophilic inflammation, and airway hyper-responsiveness. Additionally, blocking the expression of MIF in animal models leads to significant reduction of pathological signs of eosinophilic inflammation such as rhinitis, atopic dermatitis, eosinophilic esophagitis and helminth infection. A number of studies indicate that MIF is important in the effector phase of type-2 immune responses, while its contribution to Th2 differentiation and IgE production is not consensual. MIF has been found to intervene in different aspects of eosinophil physiology including differentiation, survival, activation, and migration. CD4+ T cells and eosinophils express CD74 and CXCR4, receptors able to signal upon MIF binding. Blockage of these receptors with neutralizing antibodies or small molecule antagonists also succeeds in reducing the signals of inflammation in experimental allergic models. Together, these studies demonstrate an important contribution of MIF on eosinophil biology and in the pathogenesis of allergic diseases and helminth infection.

Abdominal Actinomycosis misdiagnosed as liposarcoma.

Actinomycosis is an uncommon, endogenous, and chronic infection with varied and nonspecific clinical features such as abdominal, pelvic or cervical masses, ulcerative lesions, abscesses, draining fistula, fibrosis, and constitutional symptoms. The disease ensues when the bacteria disrupt the mucosal barrier, invade, and spread throughout interfascial planes. Currently, the diagnosis of actinomycosis is challenging because of its very low frequency and depending on the clinical presentation it may masquerade malignancies. Therapy consists initially in intravenous penicillin, followed by an oral regimen that may be extended until a year of treatment. A timely diagnosis is crucial to avoid extensive therapeutic attempt as surgery. However, a biopsy or drainage of abscesses and fistula's tract may be required not only as a diagnostic procedure as part of the therapy. We report the case of a 72-year-old woman with an abdominal mass initially misdiagnosed as a liposarcoma. A second biopsy of a skin lesion of the abdominal wall made the diagnosis of actinomycosis, avoiding a major surgical procedure. The patient was treated with a long-term course of antibiotics with favorable outcome. Liposarcoma was ruled out after the patient's full recovery with antibiotics and the misdiagnosis was credit to the overconfidence on the immunohistochemical positivity to MDM2.

[Dental recommendations in the COVID-19 pandemic: A narrative review]. / Recomendaciones odontológicas en la pandemia COVID-19: revisión narrativa.

INTRODUCTION: COVID-19 is a world public health problem due to its morbidity and mortality, especially in at-risk groups. The dental environment has a high risk of viral transmission; accordingly, this study aimed to identify recommendations based on the best available evidence for dental care during this pandemic. METHODS: We performed a search for scientific evidence published since 2002 to March 23th 2020 in electronic databases (MEDLINE/PubMed, EMBASE, Cochrane, and Epistemonikos) and the web pages of the American Dental Association, Centers for Disease Control and Prevention Oral Health, the Ministry of Health in Chile and scientific societies. RESULTS: We included nine published studies. The recommendations were the following: unrestricted use of personal protection elements, use of extraoral radiographic techniques, use of mouth rinses with 1% hydrogen peroxide or 0.2% iodine povidone, a four-hand technique with ongoing aspiration and the use of absorbable sutures. Furthermore, there is a consensus that non-urgent treatments should be postponed during periods of community transmission. CONCLUSIONS: Dental practitioners are exposed to a high risk of cross-infection, meaning they must implement recommendations based on the best available evidence to preserve the health of team members and the population they are caring for.

INTRODUCCIÓN: La enfermedad por coronavirus-19 (COVID-19) es un problema mundial de salud pública debido a su morbimortalidad, especialmente en grupos de riesgo. El entorno odontológico tiene un alto riesgo de transmisión viral, por ello el objetivo de este estudio fue identificar recomendaciones para la atención odontológica durante esta pandemia. MÉTODOS: Se realizó una búsqueda de evidencia científica publicada desde 2002 hasta el 23 de marzo de 2020 en bases de datos electrónicas (MEDLINE/PubMed, EMBASE, Cochrane y Epistemonikos) y en las páginas electrónicas de la Asociación Dental Americana, de Centers for Disease Control and Prevention Oral Health, del Ministerio de Salud de Chile y de sociedades científicas. RESULTADOS: Se incluyeron nueve artículos publicados, en los cuales se recomienda el uso irrestricto de elementos de protección personal, preferir técnicas radiográficas extraorales, uso de enjuagues bucales con peróxido de hidrógeno al 1% o povidona yodada al 0,2%, técnica a cuatro manos con aspiración constante y uso de suturas reabsorbibles. Además, existe consenso respecto a que durante los periodos de transmisión comunitaria se deben posponer los tratamientos odontológicos no urgentes. CONCLUSIONES: Debido al alto riesgo de infección cruzada que presentan los equipos odontológicos, deben implementarse recomendaciones basadas en la mejor evidencia disponible, con el fin de preservar la salud de los miembros del equipo y de la población a su cuidado.