RNA Helicase DDX1 Converts RNA G-Quadruplex Structures into R-Loops to Promote IgH Class Switch Recombination.

Class switch recombination (CSR) at the immunoglobulin heavy-chain (IgH) locus is associated with the formation of R-loop structures over switch (S) regions. While these often occur co-transcriptionally between nascent RNA and template DNA, we now show that they also form as part of a post-transcriptional mechanism targeting AID to IgH S-regions. This depends on the RNA helicase DDX1 that is also required for CSR in vivo. DDX1 binds to G-quadruplex (G4) structures present in intronic switch transcripts and converts them into S-region R-loops. This in turn targets the cytidine deaminase enzyme AID to S-regions so promoting CSR. Notably R-loop levels over S-regions are diminished by chemical stabilization of G4 RNA or by the expression of a DDX1 ATPase-deficient mutant that acts as a dominant-negative protein to reduce CSR efficiency. In effect, we provide evidence for how S-region transcripts interconvert between G4 and R-loop structures to promote CSR in the IgH locus.

Deregulated Expression of Mammalian lncRNA through Loss of SPT6 Induces R-Loop Formation, Replication Stress, and Cellular Senescence.

Extensive tracts of the mammalian genome that lack protein-coding function are still transcribed into long noncoding RNA. While these lncRNAs are generally short lived, length restricted, and non-polyadenylated, how their expression is distinguished from protein-coding genes remains enigmatic. Surprisingly, depletion of the ubiquitous Pol-II-associated transcription elongation factor SPT6 promotes a redistribution of H3K36me3 histone marks from active protein coding to lncRNA genes, which correlates with increased lncRNA transcription. SPT6 knockdown also impairs the recruitment of the Integrator complex to chromatin, which results in a transcriptional termination defect for lncRNA genes. This leads to the formation of extended, polyadenylated lncRNAs that are both chromatin restricted and form increased levels of RNA:DNA hybrid (R-loops) that are associated with DNA damage. Additionally, these deregulated lncRNAs overlap with DNA replication origins leading to localized DNA replication stress and a cellular senescence phenotype. Overall, our results underline the importance of restricting lncRNA expression.

Deacidification of endolysosomes by neuronal aging drives synapse loss.

Previously, we found that age-dependent accumulation of beta-amyloid is not sufficient to cause synaptic decline. Late-endocytic organelles (LEOs) may be driving synaptic decline as lysosomes (Lys) are a target of cellular aging and relevant for synapses. We found that LAMP1-positive LEOs increased in size and number and accumulated near synapses in aged neurons and brains. LEOs' distal accumulation might relate to the increased anterograde movement in aged neurons. Dissecting the LEOs, we found that late-endosomes accumulated while there are fewer terminal Lys in aged neurites, but not in the cell body. The most abundant LEOs were degradative Lys or endolysosomes (ELys), especially in neurites. ELys activity was reduced because of acidification defects, supported by the reduction in v-ATPase subunit V0a1 with aging. Increasing the acidification of aged ELys recovered degradation and reverted synaptic decline, while alkalinization or v-ATPase inhibition, mimicked age-dependent Lys and synapse dysfunction. We identify ELys deacidification as a neuronal mechanism of age-dependent synapse loss. Our findings suggest that future therapeutic strategies to address endolysosomal defects might be able to delay age-related synaptic decline.

Oxidized cholesteryl ester induces exocytosis of dysfunctional lysosomes in lipidotic macrophages.

A key event in atherogenesis is the formation of lipid-loaded macrophages, lipidotic cells, which exhibit irreversible accumulation of undigested modified low-density lipoproteins (LDL) in lysosomes. This event culminates in the loss of cell homeostasis, inflammation, and cell death. Nevertheless, the exact chemical etiology of atherogenesis and the molecular and cellular mechanisms responsible for the impairment of lysosome function in plaque macrophages are still unknown. Here, we demonstrate that macrophages exposed to cholesteryl hemiazelate (ChA), one of the most prevalent products of LDL-derived cholesteryl ester oxidation, exhibit enlarged peripheral dysfunctional lysosomes full of undigested ChA and neutral lipids. Both lysosome area and accumulation of neutral lipids are partially irreversible. Interestingly, the dysfunctional peripheral lysosomes are more prone to fuse with the plasma membrane, secreting their undigested luminal content into the extracellular milieu with potential consequences for the pathology. We further demonstrate that this phenotype is mechanistically linked to the nuclear translocation of the MiT/TFE family of transcription factors. The induction of lysosome biogenesis by ChA appears to partially protect macrophages from lipid-induced cytotoxicity. In sum, our data show that ChA is involved in the etiology of lysosome dysfunction and promotes the exocytosis of these organelles. This latter event is a new mechanism that may be important in the pathogenesis of atherosclerosis.

Current methods to analyze lysosome morphology, positioning, motility and function.

Since the discovery of lysosomes more than 70 years ago, much has been learned about the functions of these organelles. Lysosomes were regarded as exclusively degradative organelles, but more recent research has shown that they play essential roles in several other cellular functions, such as nutrient sensing, intracellular signalling and metabolism. Methodological advances played a key part in generating our current knowledge about the biology of this multifaceted organelle. In this review, we cover current methods used to analyze lysosome morphology, positioning, motility and function. We highlight the principles behind these methods, the methodological strategies and their advantages and limitations. To extract accurate information and avoid misinterpretations, we discuss the best strategies to identify lysosomes and assess their characteristics and functions. With this review, we aim to stimulate an increase in the quantity and quality of research on lysosomes and further ground-breaking discoveries on an organelle that continues to surprise and excite cell biologists.

Mitochondrial double-stranded RNA triggers antiviral signalling in humans.

Mitochondria are descendants of endosymbiotic bacteria and retain essential prokaryotic features such as a compact circular genome. Consequently, in mammals, mitochondrial DNA is subjected to bidirectional transcription that generates overlapping transcripts, which are capable of forming long double-stranded RNA structures1,2. However, to our knowledge, mitochondrial double-stranded RNA has not been previously characterized in vivo. Here we describe the presence of a highly unstable native mitochondrial double-stranded RNA species at single-cell level and identify key roles for the degradosome components mitochondrial RNA helicase SUV3 and polynucleotide phosphorylase PNPase in restricting the levels of mitochondrial double-stranded RNA. Loss of either enzyme results in massive accumulation of mitochondrial double-stranded RNA that escapes into the cytoplasm in a PNPase-dependent manner. This process engages an MDA5-driven antiviral signalling pathway that triggers a type I interferon response. Consistent with these data, patients carrying hypomorphic mutations in the gene PNPT1, which encodes PNPase, display mitochondrial double-stranded RNA accumulation coupled with upregulation of interferon-stimulated genes and other markers of immune activation. The localization of PNPase to the mitochondrial inter-membrane space and matrix suggests that it has a dual role in preventing the formation and release of mitochondrial double-stranded RNA into the cytoplasm. This in turn prevents the activation of potent innate immune defence mechanisms that have evolved to protect vertebrates against microbial and viral attack.

Amazon deforestation: A dangerous future indicated by patterns and trajectories in a hotspot of forest destruction in Brazil.

In recent years, the loss of forest in the Brazilian Amazon has taken on alarming proportions, with 2021 recording the largest increase in 13 years, particularly in the Abunã-Madeira Sustainable Development Reserve (SDR). This has significant environmental, social, and economic repercussions globally and for the local communities reliant on the forest. Analyzing deforestation patterns and trends aids in comprehending the dynamics of occupation and deforestation within a critical Amazon region, enabling the inference of potential occupation pathways. This understanding is crucial for identifying deforestation expansion zones and shaping public policies to curb deforestation. Decisions by the Brazilian government regarding landscape management will have profound environmental implications. We conducted an analysis of deforestation patterns and trends up to 2021 in the municipality (county) of Lábrea, located in the southern portion of Amazonas state. Deforestation processes in this area are likely to spread to the adjacent "Trans-Purus" region in western Amazonas, where Amazonia's largest block of remaining rainforest is at risk from planned highways. Annual deforestation polygons from 2008 to 2021 were categorized based on occupation typologies linked to various actors and processes defined for the region (e.g., diffuse, linear, fishbone, geometric, multidirectional, and consolidated). These patterns were represented through 10 × 10 km grid cells. The findings revealed that Lábrea's territory is predominantly characterized by the diffuse pattern (initial occupation stage), mainly concentrated in protected areas. Advanced occupation patterns (multidirectional and consolidated) were the primary contributors to deforestation during this period. Observed change trajectories included consolidation (30.8%) and expansion (19.6%) in the southern portion of the municipality, particularly along the Boi and Jequitibá secondary roads, providing access to large illegal landholdings. Additionally, non-change trajectories (67%) featured initial occupation patterns near rivers and in protected areas, likely linked to riverine and extractive communities. Tailoring measures to control deforestation based on actor types and considering stages of occupation is crucial. The techniques developed in this study provide a comprehensive approach for Amazonia and other tropical regions.

Upregulation of APP endocytosis by neuronal aging drives amyloid-dependent synapse loss.

Neuronal aging increases the risk of late-onset Alzheimer's disease. During normal aging, synapses decline, and ß-amyloid (Aß) accumulates intraneuronally. However, little is known about the underlying cell biological mechanisms. We studied neuronal aging using normal-aged brain and aged mouse primary neurons that accumulate lysosomal lipofuscin and show synapse loss. We identified the upregulation of amyloid precursor protein (APP) endocytosis as a neuronal aging mechanism that potentiates APP processing and Aß production in vitro and in vivo. The increased APP endocytosis may contribute to the early endosome enlargement observed in the aged brain. Mechanistically, we showed that clathrin-dependent APP endocytosis requires F-actin and that clathrin and endocytic F-actin increase with neuronal aging. Finally, Aß production inhibition reverts synaptic decline in aged neurons, whereas Aß accumulation, promoted by endocytosis upregulation in younger neurons, recapitulates aging-related synapse decline. Overall, we identify APP endocytosis upregulation as a potential mechanism of neuronal aging and, thus, a novel target to prevent late-onset Alzheimer's disease. This article has an associated First Person interview with the first author of the paper.

Diagnostic Yield of NGS Tests for Hereditary Ataxia: a Systematic Review.

Next-generation sequencing (NGS), comprising targeted panels (TP), exome sequencing (ES), and genome sequencing (GS) became robust clinical tools for diagnosing hereditary ataxia (HA). Determining their diagnostic yield (DY) is crucial for optimal clinical decision-making. We conducted a comprehensive systematic literature review on the DY of NGS tests for HA. We searched PubMed and Embase databases for relevant studies between 2016 and 2022 and manually examined reference lists of relevant reviews. Eligible studies described the DY of NGS tests in patients with ataxia as a significant feature. Data from 33 eligible studies showed a median DY of 43% (IQR = 9.5-100%). The median DY for TP and ES was 46% and 41.9%, respectively. Higher DY was associated with specific phenotype selection, such as episodic ataxia at 68.35% and early and late onset of ataxia at 46.4% and 54.4%. Parental consanguinity had a DY of 52.4% (p = 0.009), and the presumed autosomal recessive (AR) inheritance pattern showed 62.5%. There was a difference between the median DY of studies that performed targeted sequencing (tandem repeat expansion, TRE) screening and those that did not (p = 0.047). A weak inverse correlation was found between DY and the extent of previous genetic investigation (rho = - 0.323; p = 0.065). The most common genes were CACNA1A and SACS. DY was higher for presumed AR inheritance pattern, positive family history, and parental consanguinity. ES appears more advantageous due to the inclusion of rare genes that might be excluded in TP.

COVID-19 infection: Positive mental health, psychological vulnerability and sex: Cross-sectional study.

Since mid-March 2020, a state of emergency was decreed in Portugal due to the COVID-19 pandemic and, consequently, measures were implemented to protect public health, such as social isolation, which will certainly have a notable impact on the mental health of the population, especially in the most vulnerable groups. Positive Mental Health (PMH) is essential to deal with adversity, in this case with the pandemic, and to live better and with greater satisfaction. We consider it relevant to investigate how PMH was used as a resource to deal with the pandemic, depending on the level of vulnerability and sex. A, cross-sectional study was carried out whose the aim was to evaluate the levels of PMH and psychological vulnerability in people with COVOD-19 infection and analyze the association between PMH and psychological vulnerability among men and women. METHODS: The instruments used were a sociodemographic characterization questionnaire, the Positive Mental Health Questionnaire, and the Psychological Vulnerability Scale (PVS), that were sent and filled out online. A quantitative, cross-sectional, descriptive, and correlational study was carried out. RESULTS: After analyzing the results, it was found that approximately 50.4% of the respondents (n = 387) had global PMH values that place them in quartile 50. There was also a statistically significant difference between female and male PMH, with women showing greater psychological vulnerability and lower overall PMH. CONCLUSIONS: We conclude that the women present a greater psychological vulnerability and a lower level of PMH when compared to men. RELEVANCE TO CLINICAL PRACTICE: Considering the study's statistically significant results, when we talk about mental health, we should always consider the sex variable as a vulnerability factor, in a pandemic or non-pandemic phase.

Alzheimer's disease BIN1 coding variants increase intracellular Aß levels by interfering with BACE1 recycling.

Genetic studies have identified BIN1 as the second most important risk locus associated with late-onset Alzheimer's disease (LOAD). However, it is unclear how mutation of this locus mechanistically promotes Alzheimer's disease (AD) pathology. Here we show the consequences of two coding variants in BIN1 (rs754834233 and rs138047593), both in terms of intracellular beta-amyloid (iAbeta) accumulation and early endosome enlargement, two interrelated early cytopathological AD phenotypes, supporting their association with LOAD risk. We previously found that Bin1 deficiency potentiates iAbeta production by enabling BACE1 cleavage of the amyloid precursor protein in enlarged early endosomes due to decreased BACE1 recycling. Here, we discovered that the expression of the two LOAD mutant forms of Bin1 does not rescue the iAbeta accumulation and early endosome enlargement induced by Bin1 knockdown and recovered by wild-type Bin1. Moreover, the overexpression of Bin1 mutants, but not wild-type Bin1, increased the iAbeta42 fragment by reducing the recycling of BACE1, which accumulated in early endosomes, recapitulating the phenotype of Bin1 knockdown. We showed that the mutations in Bin1 reduced its interaction with BACE1. The endocytic recycling of transferrin was similarly affected, indicating that Bin1 is a general regulator of endocytic recycling. These data demonstrate that the LOAD-coding variants in Bin1 lead to a loss of function in endocytic recycling, which may be an early causal mechanism of LOAD.

The DNA-binding protein CTCF limits proximal Vκ recombination and restricts κ enhancer interactions to the immunoglobulin κ light chain locus.

Regulation of immunoglobulin (Ig) V(D)J gene rearrangement is dependent on higher-order chromatin organization. Here, we studied the in vivo function of the DNA-binding zinc-finger protein CTCF, which regulates interactions between enhancers and promoters. By conditional deletion of the Ctcf gene in the B cell lineage, we demonstrate that loss of CTCF allowed Ig heavy chain recombination, but pre-B cell proliferation and differentiation was severely impaired. In the absence of CTCF, the Igκ light chain locus showed increased proximal and reduced distal Vκ usage. This was associated with enhanced proximal Vκ and reduced Jκ germline transcription. Chromosome conformation capture experiments demonstrated that CTCF limits interactions of the Igκ enhancers with the proximal V(κ) gene region and prevents inappropriate interactions between these strong enhancers and elements outside the Igκ locus. Thus, although Ig gene recombination can occur in the absence of CTCF, it is a critical factor determining Vκ segment choice for recombination.

Olive tree represents a new host of a subgroup 16SrVII-B phytoplasma associated with witches' broom disease in Brazil.

Olive trees exhibiting slow development, yellowing, and high intensity of shoot proliferation with small leaves were observed in commercial plantings, in the municipality of Extrema, Minas Gerais (MG) state in 2015. The incidence of symptomatic plants was about 70% and diseased trees presented yield reduction. Here we report the association of symptomatic olive trees with a phytoplasma and describe its molecular identification. Symptomatic plants (38 trees) were sampled in three growing areas located in the same municipality. The samples consisted of bunch of leaves and young shoots. The total DNA was extracted using DNeasy® Plant Mini Kit (Qiagen, Hilden, Germany). Phytoplasma detection was conducted by nested PCR with primers P1/16S-SR (Lee et al. 2004) followed by R16F2n/R16R2 (Gundersen and Lee 1996). PCR assays generated amplicons (~1.2 kb) from 28 trees out of 38 symptomatic plants, confirming the association of phytoplasma with diseased plants. The disease was named olive witches' broom. The genomic fragments amplified by nested PCR were cloned into Escherichia coli DH5α and sequenced. The sequence representative of the olive phytoplasma was designated OWB-Br01 (Olive Wiches' Broom-Brazil 01) and deposited in GenBank under accession number MH141985. This sequence shared 99% sequence identity with phytoplasmas affiliated with 16SrVII group. According to the iPhyClassifier online tool (Zhao et al. 2009) the olive witches'-broom phytoplasma was classified as a variant of subgroup 16SrVII-B with a pattern similarity coefficient of 0.99. The phylogenetic tree showed that OWB-Br01 phytoplasma emerges from the same branch of the reference phytoplasma of the 16SrVII-B subgroup (Erigeron witchesá¾½-broom phytoplasma - GenBank AY034608), indicating that the olive tree phytoplasma is a member of the 16SrVII-B subgroup. The pathogenicity test was performed with 28 healthy plants (cultivar Arbequina) grown in pots, which were grafted by simple english forklift with scions obtained from olive plants (Arbequina) six years old, naturally infected by the phytoplasma. The initial symptoms were observed four months after grafting and at eight months 22 grafted plants exhibited slow growth, yellowing, and small leaves as those naturally observed in the fields. Molecular characterization allowed identify the phytoplasma as a member of the 16SrVII-B subgroup. In Brazil, representatives of the 16SrVII group were previously reported in association with diverse botanical species. Thus, a strain of 16SrVII-C subgroup was identified in sunn hemp (Flôres et al. 2013); the reference phytoplasma of 16SrVII-D subgroup was found in erigeron plants (Flôres et al. 2015); and the representative of 16SrVII-F was detected in the wild species Vernonia brasiliana. (Fugita et al. 2017). Specifically regarding subgroup 16SrVII-B, the reference phytoplasma of this subgroup was described from erigeron and periwinkle (Barros et al. 2002), while other members of this subgroup were reported in cauliflower (Pereira et al. 2016a) and ming aralia (Pereira et al. 2016b). The disease here studied is a threat since olive planting is in large expansion in Brazil. A potential control option could be use of propagative material from sources free of the pathogen. Based on our findings, olive tree represents a new host for subgroup 16SrVII-B phytoplasma, which is different from 16Sr groups previously reported as associated with olive witches' broom in other countries.

The Endolysosomal System and Proteostasis: From Development to Degeneration.

How do neurons adapt their endolysosomal system to address the particular challenge of membrane transport across their elaborate cellular landscape and to maintain proteostasis for the lifetime of the organism? Here we review recent findings that address this central question. We discuss the cellular and molecular mechanisms of endolysosomal trafficking and the autophagy pathway in neurons, as well as their role in neuronal development and degeneration. These studies highlight the importance of understanding the basic cell biology of endolysosomal trafficking and autophagy and their roles in the maintenance of proteostasis within the context of neurons, which will be critical for developing effective therapies for various neurodevelopmental and neurodegenerative disorders.

Bin1 and CD2AP polarise the endocytic generation of beta-amyloid.

The mechanisms driving pathological beta-amyloid (Aß) generation in late-onset Alzheimer's disease (AD) are unclear. Two late-onset AD risk factors, Bin1 and CD2AP, are regulators of endocytic trafficking, but it is unclear how their endocytic function regulates Aß generation in neurons. We identify a novel neuron-specific polarisation of Aß generation controlled by Bin1 and CD2AP We discover that Bin1 and CD2AP control Aß generation in axonal and dendritic early endosomes, respectively. Both Bin1 loss of function and CD2AP loss of function raise Aß generation by increasing APP and BACE1 convergence in early endosomes, however via distinct sorting events. When Bin1 levels are reduced, BACE1 is trapped in tubules of early endosomes and fails to recycle in axons. When CD2AP levels are reduced, APP is trapped at the limiting membrane of early endosomes and fails to be sorted for degradation in dendrites. Hence, Bin1 and CD2AP keep APP and BACE1 apart in early endosomes by distinct mechanisms in axon and dendrites. Individuals carrying variants of either factor would slowly accumulate Aß in neurons increasing the risk for late-onset AD.

Impact of late-onset Alzheimer's genetic risk factors on beta-amyloid endocytic production.

The increased production of the 42 aminoacids long beta-amyloid (Aß42) peptide has been established as a causal mechanism of the familial early onset Alzheimer's disease (AD). In contrast, the causal mechanisms of the late-onset AD (LOAD), that affects most AD patients, remain to be established. Indeed, Aß42 accumulation has been detected more than 30 years before diagnosis. Thus, the mechanisms that control Aß accumulation in LOAD likely go awry long before pathogenesis becomes detectable. Early on, APOE4 was identified as the biggest genetic risk factor for LOAD. However, since APOE4 is not present in all LOAD patients, genome-wide association studies of thousands of LOAD patients were undertaken to identify other genetic variants that could explain the development of LOAD. PICALM, BIN1, CD2AP, SORL1, and PLD3 are now with APOE4 among the identified genes at highest risk in LOAD that have been implicated in Aß42 production. Recent evidence indicates that the regulation of the endocytic trafficking of the amyloid precursor protein (APP) and/or its secretases to and from sorting endosomes is determinant for Aß42 production. Thus, here, we will review the described mechanisms, whereby these genetic risk factors can contribute to the enhanced endocytic production of Aß42. Dissecting causal LOAD mechanisms of Aß42 accumulation, underlying the contribution of each genetic risk factor, will be required to identify therapeutic targets for novel personalized preventive strategies.

Membrane re-arrangements and rippled phase stabilisation by the cell penetrating peptide penetratin.

Cell penetrating peptides are promising vectors for molecular drug delivery in eukaryotic cells. Despite of their discovery 20years ago, the mechanisms of peptide membrane crossing are still controversial. The different suggested penetration mechanisms reflect the high sequence and structural diversity of cell penetrating peptides. The fundamental step for peptide penetration into the cytosol is the crossing of the membrane lipid barrier at the level of the plasma membrane or the endosomes. Therefore, the study of the peptide-lipid interaction is the key for peptide penetration mechanisms understanding. In order to study the changes in lipid organisation induced by the cell penetrating peptide penetratin, several experiments by three different physicochemical approaches were performed. X-ray diffraction data shows that penetratin is able to induce membrane phase separation and lipid rearrangements observed by inter-lipid distances. These changes are accompanied by a temperature stable behaviour of some of the induced membrane domains. The membrane environment fluorescent probe laurdan showed that, in DMPC and DMPC/DMPG membranes, the peptide induces de-packing of lipids. Calorimetric analyses show that penetratin favours the gel phase to gel-like rippled phase transition. Overall, the data suggest both, that the rippled phase is a heterogeneous structure formed by gel-like and fluid-like coexisting components, and that the penetratin-induced membrane heterogeneity could be important for membrane destabilisation during cell penetration.

Pre-B cell receptor signaling induces immunoglobulin κ locus accessibility by functional redistribution of enhancer-mediated chromatin interactions.

During B cell development, the precursor B cell receptor (pre-BCR) checkpoint is thought to increase immunoglobulin κ light chain (Igκ) locus accessibility to the V(D)J recombinase. Accordingly, pre-B cells lacking the pre-BCR signaling molecules Btk or Slp65 showed reduced germline V(κ) transcription. To investigate whether pre-BCR signaling modulates V(κ) accessibility through enhancer-mediated Igκ locus topology, we performed chromosome conformation capture and sequencing analyses. These revealed that already in pro-B cells the κ enhancers robustly interact with the ∼3.2 Mb V(κ) region and its flanking sequences. Analyses in wild-type, Btk, and Slp65 single- and double-deficient pre-B cells demonstrated that pre-BCR signaling reduces interactions of both enhancers with Igκ locus flanking sequences and increases interactions of the 3'κ enhancer with V(κ) genes. Remarkably, pre-BCR signaling does not significantly affect interactions between the intronic enhancer and V(κ) genes, which are already robust in pro-B cells. Both enhancers interact most frequently with highly used V(κ) genes, which are often marked by transcription factor E2a. We conclude that the κ enhancers interact with the V(κ) region already in pro-B cells and that pre-BCR signaling induces accessibility through a functional redistribution of long-range chromatin interactions within the V(κ) region, whereby the two enhancers play distinct roles.

An Interesting Case of Viral Pericarditis.

A previously healthy 14-year-old girl presented to the emergency department with a 3-day history of upper respiratory symptoms and 2 syncopal episodes. She was initially febrile, tachycardic, and tachypneic; the initial electrocardiogram showed diffuse T-wave inversions and right atrial enlargement. There was no pericardial effusion on bedside and formal echocardiography; the latter, however, revealed a hyperechogenic pericardium. A viral swab was positive for influenza B. Treatment with intravenous rehydration and ibuprofen was started with good response. The patient went home 24 hours later with the diagnosis of mild pericarditis and syncope likely secondary to dehydration impaired diastolic filling.The incidence of acute pericarditis in previously healthy children is unknown. There are no known case reports of influenza B-associated pericarditis in the pediatric population. There is little high quality evidence to guide the diagnosis and management of pericarditis in children. However, limited data suggest that the typically described presentation of chest pain, pericardial rub, pericardial effusion, and electrocardiogram changes occurs in children. The pediatric population seems to respond well to nonsteroidal anti-inflammatory drugs.

Costs of topical treatment of pressure ulcer patients.

OBJECTIVE: To evaluate the costs of a topical treatment of pressure ulcer (PU) patients in a hospital unit for treatment of chronic patients in 2014. METHOD: This is an activity-based costing study. This method encompasses the identification, measurement and pricing of physical and human resources consumed for dressings. RESULTS: Procedure costs varied between BRL 16.41 and BRL 260.18. For PUs of the same category, of near areas and with the same type of barrier/adjuvant, the cost varied between 3.5% and 614.6%. For most dressings, the cost increased proportionally to the increase of the area and to the development of PU category. The primary barrier accounted for a high percentage of costs among all items required to the application of dressings (human and material resources). Dressings applied in sacral PUs had longer application times. CONCLUSION: This study allowed us to understand the costs involved in the treatment of PUs, and it may support decision-makers and other cost-effectiveness studies. OBJETIVO: Realizar uma avaliação do custo do tratamento tópico de pacientes com úlceras por pressão (UP), em uma unidade hospitalar de atendimento a pacientes crônicos no ano de 2014. MÉTODO: Trata-se de um estudo de custos baseado no Sistema de custeio Baseado em Atividades. Este método contempla a identificação, mensuração e precificação dos recursos físicos e humanos consumidos para a realização de curativos. RESULTADOS: Os custos dos procedimentos variaram de R$16,41 a R$260,18. Para UP de mesma categoria, de áreas aproximadas e mesmo tipo de cobertura/adjuvante, a variação entre os custos foi de 3,5% a 614,6%. Para a maioria dos curativos, o custo aumentou proporcionalmente ao aumento da área e à progressão da categoria das UP. A cobertura primária representou elevado percentual nos custos entre todos os itens necessários para realizar os curativos (recursos humanos e materiais). Os curativos realizados nas UP sacrais foram os que apresentaram maiores tempos para execução. CONCLUSÃO: Este estudo permitiu conhecer os custos envolvidos no tratamento das UP e pode fornecer subsídios para os tomadores de decisão, assim como para a realização de estudos de custo-efetividade.