Replicative Acinetobacter baumannii strains interfere with phagosomal maturation by modulating the vacuolar pH.

Bacterial pneumonia is a common infection of the lower respiratory tract that can afflict patients of all ages. Multidrug-resistant strains of Acinetobacter baumannii are increasingly responsible for causing nosocomial pneumonias, thus posing an urgent threat. Alveolar macrophages play a critical role in overcoming respiratory infections caused by this pathogen. Recently, we and others have shown that new clinical isolates of A. baumannii, but not the common lab strain ATCC 19606 (19606), can persist and replicate in macrophages within spacious vacuoles that we called Acinetobacter Containing Vacuoles (ACV). In this work, we demonstrate that the modern A. baumannii clinical isolate 398, but not the lab strain 19606, can infect alveolar macrophages and produce ACVs in vivo in a murine pneumonia model. Both strains initially interact with the macrophage endocytic pathway, as indicated by EEA1 and LAMP1 markers; however, the fate of these strains diverges at a later stage. While 19606 is eliminated in an autophagy pathway, 398 replicates in ACVs and are not degraded. We show that 398 reverts the natural acidification of the phagosome by secreting large amounts of ammonia, a by-product of amino acid catabolism. We propose that this ability to survive within macrophages may be critical for the persistence of clinical A. baumannii isolates in the lung during a respiratory infection.

High frequency oscillations in human memory and cognition: a neurophysiological substrate of engrams?

Despite advances in understanding the cellular and molecular processes underlying memory and cognition, and recent successful modulation of cognitive performance in brain disorders, the neurophysiological mechanisms remain underexplored. High frequency oscillations beyond the classic electroencephalogram spectrum have emerged as a potential neural correlate of fundamental cognitive processes. High frequency oscillations are detected in the human mesial temporal lobe and neocortical intracranial recordings spanning gamma/epsilon (60-150 Hz), ripple (80-250 Hz) and higher frequency ranges. Separate from other non-oscillatory activities, these brief electrophysiological oscillations of distinct duration, frequency and amplitude are thought to be generated by coordinated spiking of neuronal ensembles within volumes as small as a single cortical column. Although the exact origins, mechanisms and physiological roles in health and disease remain elusive, they have been associated with human memory consolidation and cognitive processing. Recent studies suggest their involvement in encoding and recall of episodic memory with a possible role in the formation and reactivation of memory traces. High frequency oscillations are detected during encoding, throughout maintenance, and right before recall of remembered items, meeting a basic definition for an engram activity. The temporal coordination of high frequency oscillations reactivated across cortical and subcortical neural networks is ideally suited for integrating multimodal memory representations, which can be replayed and consolidated during states of wakefulness and sleep. High frequency oscillations have been shown to reflect coordinated bursts of neuronal assembly firing and offer a promising substrate for tracking and modulation of the hypothetical electrophysiological engram.

Evolutionarily stable gene clusters shed light on the common grounds of pathogenicity in the Acinetobacter calcoaceticus-baumannii complex.

Nosocomial pathogens of the Acinetobacter calcoaceticus-baumannii (ACB) complex are a cautionary example for the world-wide spread of multi- and pan-drug resistant bacteria. Aiding the urgent demand for novel therapeutic targets, comparative genomics studies between pathogens and their apathogenic relatives shed light on the genetic basis of human-pathogen interaction. Yet, existing studies are limited in taxonomic scope, sensing of the phylogenetic signal, and resolution by largely analyzing genes independent of their organization in functional gene clusters. Here, we explored more than 3,000 Acinetobacter genomes in a phylogenomic framework integrating orthology-based phylogenetic profiling and microsynteny conservation analyses. We delineate gene clusters in the type strain A. baumannii ATCC 19606 whose evolutionary conservation indicates a functional integration of the subsumed genes. These evolutionarily stable gene clusters (ESGCs) reveal metabolic pathways, transcriptional regulators residing next to their targets but also tie together sub-clusters with distinct functions to form higher-order functional modules. We shortlisted 150 ESGCs that either co-emerged with the pathogenic ACB clade or are preferentially found therein. They provide a high-resolution picture of genetic and functional changes that coincide with the manifestation of the pathogenic phenotype in the ACB clade. Key innovations are the remodeling of the regulatory-effector cascade connecting LuxR/LuxI quorum sensing via an intermediate messenger to biofilm formation, the extension of micronutrient scavenging systems, and the increase of metabolic flexibility by exploiting carbon sources that are provided by the human host. We could show experimentally that only members of the ACB clade use kynurenine as a sole carbon and energy source, a substance produced by humans to fine-tune the antimicrobial innate immune response. In summary, this study provides a rich and unbiased set of novel testable hypotheses on how pathogenic Acinetobacter interact with and ultimately infect their human host. It is a comprehensive resource for future research into novel therapeutic strategies.

Categorization of the amyotrophic lateral sclerosis population via the clinical determinant of post-onset ΔFS for study design and medical practice.

The amyotrophic lateral sclerosis (ALS) functional rating scale-revised (ALSFRS-R) has become the most widely utilized measure of disease severity in patients with ALS, with change in ALSFRS-R from baseline being a trusted primary outcome measure in ALS clinical trials. This is despite the scale having several established limitations, and although alternative scales have been proposed, it is unlikely that these will displace ALSFRS-R in the foreseeable future. Here, we discuss the merits of delta FS (ΔFS), the slope or rate of ALSFRS-R decline over time, as a relevant tool for innovative ALS study design, with an as yet untapped potential for optimization of drug effectiveness and patient management. In our view, categorization of the ALS population via the clinical determinant of post-onset ΔFS is an important study design consideration. It serves not only as a critical stratification factor and basis for patient enrichment but also as a tool to explore differences in treatment response across the overall population; thereby, facilitating identification of responder subgroups. Moreover, because post-onset ΔFS is derived from information routinely collected as part of standard patient care and monitoring, it provides a suitable patient selection tool for treating physicians. Overall, post-onset ΔFS is a very attractive enrichment tool that is, can and should be regularly incorporated into ALS trial design.

European Academy of Neurology (EAN) guideline on the management of amyotrophic lateral sclerosis in collaboration with European Reference Network for Neuromuscular Diseases (ERN EURO-NMD).

BACKGROUND: This update of the guideline on the management of amyotrophic lateral sclerosis (ALS) was commissioned by the European Academy of Neurology (EAN) and prepared in collaboration with the European Reference Network for Neuromuscular Diseases (ERN EURO-NMD) and the support of the European Network for the Cure ALS (ENCALS) and the European Organization for Professionals and Patients with ALS (EUpALS). METHODS: Grading of Recommendations Assessment, Development, and Evaluation (GRADE) methodology was used to assess the effectiveness of interventions for ALS. Two systematic reviewers from Cochrane Response supported the guideline panel. The working group identified a total of 26 research questions, performed systematic reviews, assessed the quality of the available evidence, and made specific recommendations. Expert consensus statements were provided where insufficient evidence was available. RESULTS: A guideline mapping effort revealed only one other ALS guideline that used GRADE methodology (a National Institute for Health and Care Excellence [NICE] guideline). The available evidence was scarce for many research questions. Of the 26 research questions evaluated, the NICE recommendations could be adapted for 8 questions. Other recommendations required updates of existing systematic reviews or de novo reviews. Recommendations were made on currently available disease-modifying treatments, multidisciplinary care, nutritional and respiratory support, communication aids, psychological support, treatments for common ALS symptoms (e.g., muscle cramps, spasticity, pseudobulbar affect, thick mucus, sialorrhea, pain), and end-of-life management. CONCLUSIONS: This update of the guideline using GRADE methodology provides a framework for the management of ALS. The treatment landscape is changing rapidly, and further updates will be prepared when additional evidence becomes available.

Genetic variability in sporadic amyotrophic lateral sclerosis.

With the advent of gene therapies for amyotrophic lateral sclerosis (ALS), there is a surge in gene testing for this disease. Although there is ample experience with gene testing for C9orf72, SOD1, FUS and TARDBP in familial ALS, large studies exploring genetic variation in all ALS-associated genes in sporadic ALS (sALS) are still scarce. Gene testing in a diagnostic setting is challenging, given the complex genetic architecture of sALS, for which there are genetic variants with large and small effect sizes. Guidelines for the interpretation of genetic variants in gene panels and for counselling of patients are lacking. We aimed to provide a thorough characterization of genetic variability in ALS genes by applying the American College of Medical Genetics and Genomics (ACMG) criteria on whole genome sequencing data from a large cohort of 6013 sporadic ALS patients and 2411 matched controls from Project MinE. We studied genetic variation in 90 ALS-associated genes and applied customized ACMG-criteria to identify pathogenic and likely pathogenic variants. Variants of unknown significance were collected as well. In addition, we determined the length of repeat expansions in C9orf72, ATXN1, ATXN2 and NIPA1 using the ExpansionHunter tool. We found C9orf72 repeat expansions in 5.21% of sALS patients. In 50 ALS-associated genes, we did not identify any pathogenic or likely pathogenic variants. In 5.89%, a pathogenic or likely pathogenic variant was found, most commonly in SOD1, TARDBP, FUS, NEK1, OPTN or TBK1. Significantly more cases carried at least one pathogenic or likely pathogenic variant compared to controls (odds ratio 1.75; P-value 1.64 × 10-5). Isolated risk factors in ATXN1, ATXN2, NIPA1 and/or UNC13A were detected in 17.33% of cases. In 71.83%, we did not find any genetic clues. A combination of variants was found in 2.88%. This study provides an inventory of pathogenic and likely pathogenic genetic variation in a large cohort of sALS patients. Overall, we identified pathogenic and likely pathogenic variants in 11.13% of ALS patients in 38 known ALS genes. In line with the oligogenic hypothesis, we found significantly more combinations of variants in cases compared to controls. Many variants of unknown significance may contribute to ALS risk, but diagnostic algorithms to reliably identify and weigh them are lacking. This work can serve as a resource for counselling and for the assembly of gene panels for ALS. Further characterization of the genetic architecture of sALS is necessary given the growing interest in gene testing in ALS.

Morphological and molecular characterization of Stomachicola muraenesocis Yamaguti, 1934 (Digenea: Hemiuridae) from the daggertooth pike conger Muraenesox cinereus (Forsskål).

Hemiurid digeneans conspecific with Stomachicola muraenesocis Yamaguti, 1934 (the type species of the genus Stomachicola Yamaguti, 1934) were collected from the stomach of the daggertooth pike conger Muraenesox cinereus (Forsskål) off the Persian Gulf of Iran. This study aimed to provide a detailed characterization of Stom. muraenesocis, including measurements, illustrations and scanning electron microscopy (s.e.m.) representations. Comparisons with the original and previous descriptions revealed morphological and metrical variations in several features (i.e. body size and shape, arrangement of reproductive organs, soma to ecsoma length ratio, position of genital opening, number of vitelline tubules and extension of uterine coils) between Stom. muraenesocis from different hosts and localities. This study presents the first molecular sequence data associated with the small (18S) and large (28S) subunit nuclear ribosomal RNA genes (rDNA) for Stom. muraenesocis. Phylogenetic analyses of the 18S dataset placed Stom. muraenesocis as sister lineage to a clade formed of a group of species of Lecithaster Lühe, 1901 (Lecithasteridae Odhner, 1905). In contrast, phylogenetic analyses based on the 28S consistently recovered a sister relationship between Stom. muraenesocis and representatives of the Hemiuridae Looss, 1899. Further comprehensive phylogenetically based classification in light of morphology and taxonomic history of the Hemiuridae and Lecithasteridae is required to infer phylogenetic affinities and historical biogeography of Stomachicola. A comprehensive list of previously reported species of Stomachicola together with their associated hosts, localities and morphometric data is provided.

Increased Incidence of TdT-negative Pre-B Acute Lymphoblastic Leukemia Associated With Poor Prognostic Features Among Mexican Children in Central Mexico.

Mexican and Hispanic children in Mexico and the United States, respectively, have the highest incidence and worst outcomes of pre-B acute lymphoblastic leukemia (ALL) compared with other racial/ethnic groups. Terminal deoxynucleotidyl transferase (TdT) is an intranuclear DNA polymerase normally present on immature lymphocytes (TdT-positive) and distinguishes ALL from mature lymphoid malignancies. We performed a multisite retrospective study to determine the incidence of TdT-negative precursor B-cell acute lymphoblastic leukemia (pre-B ALL) among Mexican, Caucasian, and US-born Hispanic children to correlate TdT expression with patient characteristics and known prognostic factors. Fisher exact test was performed for categorical variables and the Wilcoxon rank-sum test was used for continuous variables. TdT-negative pre-B ALL was most frequently identified in patients with National Cancer Institute high-risk disease ( P =0.014). TdT-negative expression was also most frequently associated with hypodiploid pre-B ALL ( P =0.001) and KMT2A gene rearrangement ( P =0.0012). Mexican children had the highest incidence of TdT-negative ALL compared with Caucasians and US Hispanics ( P <0.001), with an increased incidence of poor prognostic features as well. This study demonstrates significant differences in TdT-negative expression, genomic alterations, and leukemic ploidy based on race and ethnicity.

Clinical-epidemiological characterization of patients with long COVID in Mexico.

BACKGROUND: Long COVID is defined as the persistence of COVID-19 symptoms four weeks after having undergone acute infection, according to the most recent CDC definition. It is estimated that there are 65 million people affected by this entity, although other figures speak of 200 million. OBJECTIVE: To characterize the population affected by long COVID in Mexico. MATERIAL AND METHODS: Patients older than 18 years who agreed to answer an online survey and who met the criteria for long COVID were included. RESULTS: Data from 203 subjects were included, with 138 (68.0%) being found to be females, and average age to be 41.8 years; 29.6% had severe disease, and 70.4%, mild to moderate disease; 89.7% had received prior COVID-19 vaccination: 6.9% had received one dose; 31.5%, two doses; and 51.2%, three or more doses. The main risk factors were diabetes, overweight or obesity, and hypertension. The most commonly reported symptom was fatigue, followed by other neuropsychiatric manifestations. CONCLUSION: It is important for the population affected by long COVID to be characterized in order to generate diagnostic and treatment protocols.

ANTECEDENTES: El COVID persistente se define como la persistencia de síntomas de COVID-19 después de cuatro semanas de cursar con un cuadro agudo, según la definición más reciente de los Centers for Disease Control and Prevention. Se estima que existen 65 millones de personas afectadas por esta entidad, aunque algunos reportes indican 200 millones. OBJETIVO: Caracterizar a la población afectada por COVID persistente en México. MATERIAL Y MÉTODOS: Se incluyeron pacientes mayores de 18 años que consintieron responder a una encuesta en línea y que cumplían los criterios de COVID persistente. RESULTADOS: Se incluyeron los datos de 203 sujetos. Se identificó que 138 (68.0 %) contestaron ser del sexo femenino, con una media de edad de 41.8 años; 29.6 % presentó enfermedad grave y 70.4 %, enfermedad leve a moderada; 89.7 % había recibido vacunas previas para COVID-19: 6.9 %, una dosis; 31.5 %, dos dosis; y 51.2 %, tres o más dosis. Los principales factores de riesgo fueron diabetes, sobrepeso u obesidad e hipertensión arterial sistémica. El principal síntoma reportado fue fatiga, seguido de otras manifestaciones neuropsiquiátricas. CONCLUSIÓN: Es importante caracterizar a la población para generar protocolos de diagnóstico y tratamiento.

Race Dynamics in Triathlon Mixed-Team-Relay Meaningfully Changes with The New Regulation Towards Paris 2024.

Mixed-Team-Relay (MTR) triathlon is a novel Olympic discipline whose performance determinants and tactical behaviors have barely been studied. Additionally, a regulatory change has been made to the male and female relay order for the Paris 2024 Olympics. Therefore, this study aimed to determine the performance determinants and race dynamics as a function of competitive level on the new regulated MTR triathlon. Results from 129 national teams, (516 elite triathletes) across five MTR World Triathlon Series and two MTR European Championships in 2022 and 2023, were analyzed. Split times, average speeds, time behind the race leader (gap), partial and finishing positions, pack position as well as the rank positions of every segment, relay leg, and overall race were computed. Decision tree analyses were conducted as a predictive method for the overall results, and correspondence analyses were conducted to examine the relationship between the different relay legs and segments and the finishing positions. The performance of the fourth leg was the most relevant for overall result (30%), as well as the fourth running leg (16%) and the female legs performance (7%). Medallist relay teams were characterized by displaying a differential speed lower than 0.5 and 0.83 km/h, respectively, from the best-ranking athletes in the Legs 1 and 4. Furthermore, staying in the front pack after the second swimming leg showed a great relationship with achieving a medal position. New MTR triathlon rules shift race dynamics, emphasizing individual efforts in cycling and swimming, while maintaining the crucial importance of running.

Macrophage N-glycan processing inhibits antibody-dependent cellular phagocytosis.

Factors regulating macrophage effector function represent potential targets to optimize the efficacy of antibody-mediated therapies. Macrophages are myeloid cells capable of engulfing and destroying diseased or damaged target cells. Antibodies binding to the target cell surface can engage macrophage Fc gamma receptors (FcγRs) to elicit antibody-dependent cellular phagocytosis (ADCP), a process that contributes to treatments mediated by anti-tumor antibodies. Conversely, macrophage ADCP of apoptotic T cells is also linked to tolerance in the tumor environment. Here we evaluated the role of asparagine(N)-linked glycans in the function of macrophages derived from primary human monocytes. Macrophages treated with kifunensine, an inhibitor of N-glycan processing, exhibited greater target binding and ADCP of antibody-coated target cells. Kifunensine treatment increased ADCP of both rituximab-coated Raji B cells and trastuzumab-coated SKBR3 cells. ADCP required FcγRs; inhibiting CD64 / FcγRI led to the greatest reduction, followed by CD32 / FcγRII and then CD16 / FcγRIII in most donors. Kifunensine treatment also increased the antibody-binding affinity of CD16. Differences in the abundance of phosphorylated immune receptors, including Siglec-9, CD32a, and LAIR-1 correlated with the increased ADCP. These results demonstrate that N-glycan processing regulates macrophage effector function.

The role of Gata3 in renin cell identity.

Renin cells are precursors for other cell types in the kidney and show high plasticity in postnatal life in response to challenges to homeostasis. Our previous single-cell RNA-sequencing studies revealed that the dual zinc-finger transcription factor Gata3, which is important for cell lineage commitment and differentiation, is expressed in mouse renin cells under normal conditions and homeostatic threats. We identified a potential Gata3-binding site upstream of the renin gene leading us to hypothesize that Gata3 is essential for renin cell identity. We studied adult mice with conditional deletion of Gata3 in renin cells: Gata3fl/fl;Ren1dCre/+ (Gata3-cKO) and control Gata3fl/fl;Ren1d+/+ counterparts. Gata3 immunostaining revealed that Gata3-cKO mice had significantly reduced Gata3 expression in juxtaglomerular, mesangial, and smooth muscle cells, indicating a high degree of deletion of Gata3 in renin lineage cells. Gata3-cKO mice exhibited a significant increase in blood urea nitrogen, suggesting hypovolemia and/or compromised renal function. By immunostaining, renin-expressing cells appeared very thin compared with their normal plump shape in control mice. Renin cells were ectopically localized to Bowman's capsule in some glomeruli, and there was aberrant expression of actin-α2 signals in the mesangium, interstitium, and Bowman's capsule in Gata3-cKO mice. Distal tubules showed dilated morphology with visible intraluminal casts. Under physiological threat, Gata3-cKO mice exhibited a lower increase in mRNA levels than controls. Hematoxylin-eosin, periodic acid-Schiff, and Masson's trichrome staining showed increased glomerular fusion, absent cubical epithelial cells in Bowman's capsule, intraglomerular aneurysms, and tubular dilation. In conclusion, our results indicate that Gata3 is crucial to the identity of cells of the renin lineage.NEW & NOTEWORTHY Gata3, a dual zinc-finger transcription factor, is responsible for the identity and localization of renin cells in the kidney. Mice with a conditional deletion of Gata3 in renin lineage cells have abnormal kidneys with juxtaglomerular cells that lose their characteristic location and are misplaced outside and around arterioles and glomeruli. The fundamental role of Gata3 in renin cell development offers a new model to understand how transcription factors control cell location, function, and pathology.

Modern Acinetobacter baumannii clinical isolates replicate inside spacious vacuoles and egress from macrophages.

Multidrug-resistant Acinetobacter baumannii infections are increasing at alarming rates. Therefore, novel antibiotic-sparing treatments to combat these A. baumannii infections are urgently needed. The development of these interventions would benefit from a better understanding of this bacterium's pathobiology, which remains poorly understood. A. baumannii is regarded as an extracellular opportunistic pathogen. However, research on Acinetobacter has largely focused on common lab strains, such as ATCC 19606, that have been isolated several decades ago. These strains exhibit reduced virulence when compared to recently isolated clinical strains. In this work, we demonstrate that, unlike ATCC 19606, several modern A. baumannii clinical isolates, including the recent clinical urinary isolate UPAB1, persist and replicate inside macrophages within spacious vacuoles. We show that intracellular replication of UPAB1 is dependent on a functional type I secretion system (T1SS) and pAB5, a large conjugative plasmid that controls the expression of several chromosomally-encoded genes. Finally, we show that UPAB1 escapes from the infected macrophages by a lytic process. To our knowledge, this is the first report of intracellular growth and replication of A. baumannii. We suggest that intracellular replication within macrophages may contribute to evasion of the immune response, dissemination, and antibiotic tolerance of A. baumannii.

Glycan node profiling of soluble and membrane glycoproteins in whole cell lysates.

Glycan node analysis (GNA) is a molecularly bottom-up glycomics technique based on the relative quantification of glycan linkage-specific monosaccharide units ("glycan nodes"). It was originally applied to blood plasma/serum, where it detected and predicted progression, reoccurrence, and survival in different types of cancer. Here, we have adapted this technology to previously inaccessible membrane glycoproteins from cultured cells. The approach is facilitated by methanol/chloroform precipitation of cell lysates and a "liquid phase permethylation" (LPP) procedure. LPP gave better signal-to-noise, yield and precision for most of the glycan nodes from membrane glycoproteins/glycolipids than the conventional solid phase permethylation approach. This GNA approach in cell lysates revealed that specific glycan features such as antennary fucosylation, N-glycan branching, and α2,6-sialylation were elevated in hepatocellular carcinoma (HepG2) cells relative to leukemia cells (THP-1 and K562) and normal donor PBMCs. Additional nodes commonly associated with glycolipids were elevated in the leukemia cells relative to HepG2 cells and PBMCs. Exposure of HepG2 cells to a fucosyltransferase inhibitor resulted in a significant reduction in the relative abundance of 3,4-substituted GlcNAc, which represents antennary fucosylation-providing further proof-of-concept that downregulation of glycosyltransferase activity is detected by shifts in glycan node expression-now detectable in membrane glycoproteins.

Ezrin and CD44 participate in the internalization process of Coxiella burnetii into non-phagocytic cells.

Ezrin protein is involved in the interaction of actin cytoskeleton with membrane receptors such as CD44. It regulates plasma membrane dynamics and intracellular signaling. Coxiella burnetii, the etiologic agent of Q fever, is internalized into host cell through a poorly characterized molecular mechanism. Here we analyzed the role of ezrin and CD44 in the C. burnetii internalization by HeLa cells. The knockdown of ezrin and CD44 inhibited the bacterial uptake. Interestingly, at early stages of C. burnetii internalization, ezrin was recruited to the cell membrane fraction and phosphorylated. Moreover, the overexpression of non-phosphorylatable and phosphomimetic ezrin mutants decreased and increased the bacterial entry, respectively. A decrease in the internalization of C. burnetii was observed by the overexpression of CD44 truncated forms containing the intracellular or the extracellular domains. Interestingly, the CD44 mutant was unable to interact with ERM proteins decreased the bacterial internalization. These findings demonstrate the participation of ezrin in the internalization process of C. burnetii in non-phagocytic cells. Additionally, we present evidence that CD44 receptor would be involved in that process.

Glycan Node Analysis Detects Varying Glycosaminoglycan Levels in Melanoma-Derived Extracellular Vesicles.

Extracellular vesicles (EVs) play important roles in (patho)physiological processes by mediating cell communication. Although EVs contain glycans and glycosaminoglycans (GAGs), these biomolecules have been overlooked due to technical challenges in comprehensive glycome analysis coupled with EV isolation. Conventional mass spectrometry (MS)-based methods are restricted to the assessment of N-linked glycans. Therefore, methods to comprehensively analyze all glyco-polymer classes on EVs are urgently needed. In this study, tangential flow filtration-based EV isolation was coupled with glycan node analysis (GNA) as an innovative and robust approach to characterize most major glyco-polymer features of EVs. GNA is a molecularly bottom-up gas chromatography-MS technique that provides unique information that is unobtainable with conventional methods. The results indicate that GNA can identify EV-associated glyco-polymers that would remain undetected with conventional MS methods. Specifically, predictions based on GNA identified a GAG (hyaluronan) with varying abundance on EVs from two different melanoma cell lines. Enzyme-linked immunosorbent assays and enzymatic stripping protocols confirmed the differential abundance of EV-associated hyaluronan. These results lay the framework to explore GNA as a tool to assess major glycan classes on EVs, unveiling the EV glycocode and its biological functions.

Anti-Melanogenic Potential of Natural and Synthetic Substances: Application in Zebrafish Model.

Melanogenesis is a biosynthetic pathway for the formation of the pigment melanin in human skin. A key enzyme in the process of pigmentation through melanin is tyrosinase, which catalyzes the first and only limiting step in melanogenesis. Since the discovery of its methanogenic properties, tyrosinase has been the focus of research related to the anti-melanogenesis. In addition to developing more effective and commercially safe inhibitors, more studies are required to better understand the mechanisms involved in the skin depigmentation process. However, in vivo assays are necessary to develop and validate new drugs or molecules for this purpose, and to accomplish this, zebrafish has been identified as a model organism for in vivo application. In addition, such model would allow tracking and studying the depigmenting activity of many bioactive compounds, important to genetics, medicinal chemistry and even the cosmetic industry. Studies have shown the similarity between human and zebrafish genomes, encouraging their use as a model to understand the mechanism of action of a tested compound. Interestingly, zebrafish skin shares many similarities with human skin, suggesting that this model organism is suitable for studying melanogenesis inhibitors. Accordingly, several bioactive compounds reported herein for this model are compared in terms of their molecular structure and possible mode of action in zebrafish embryos. In particular, this article described the main metabolites of Trichoderma fungi, in addition to substances from natural and synthetic sources.

Awake prone positioning and oxygen therapy in patients with COVID-19: the APRONOX study.

BACKGROUND: The awake prone positioning strategy for patients with acute respiratory distress syndrome is a safe, simple and cost-effective technique used to improve hypoxaemia. We aimed to evaluate intubation and mortality risk in patients with coronavirus disease 2019 (COVID-19) who underwent awake prone positioning during hospitalisation. METHODS: In this retrospective, multicentre observational study conducted between 1 May 2020 and 12 June 2020 in 27 hospitals in Mexico and Ecuador, nonintubated patients with COVID-19 managed with awake prone or awake supine positioning were included to evaluate intubation and mortality risk through logistic regression models; multivariable and centre adjustment, propensity score analyses, and E-values were calculated to limit confounding. RESULTS: 827 nonintubated patients with COVID-19 in the awake prone (n=505) and awake supine (n=322) groups were included for analysis. Fewer patients in the awake prone group required endotracheal intubation (23.6% versus 40.4%) or died (19.8% versus 37.3%). Awake prone positioning was a protective factor for intubation even after multivariable adjustment (OR 0.35, 95% CI 0.24-0.52; p<0.0001, E=2.12), which prevailed after propensity score analysis (OR 0.41, 95% CI 0.27-0.62; p<0.0001, E=1.86) and mortality (adjusted OR 0.38, 95% CI 0.26-0.55; p<0.0001, E=2.03). The main variables associated with intubation among awake prone patients were increasing age, lower baseline peripheral arterial oxygen saturation/inspiratory oxygen fraction ratio (P aO2 /F IO2 ) and management with a nonrebreather mask. CONCLUSIONS: Awake prone positioning in hospitalised nonintubated patients with COVID-19 is associated with a lower risk of intubation and mortality.

The Effect of SMN Gene Dosage on ALS Risk and Disease Severity.

OBJECTIVE: The role of the survival of motor neuron (SMN) gene in amyotrophic lateral sclerosis (ALS) is unclear, with several conflicting reports. A decisive result on this topic is needed, given that treatment options are available now for SMN deficiency. METHODS: In this largest multicenter case control study to evaluate the effect of SMN1 and SMN2 copy numbers in ALS, we used whole genome sequencing data from Project MinE data freeze 2. SMN copy numbers of 6,375 patients with ALS and 2,412 controls were called from whole genome sequencing data, and the reliability of the calls was tested with multiplex ligation-dependent probe amplification data. RESULTS: The copy number distribution of SMN1 and SMN2 between cases and controls did not show any statistical differences (binomial multivariate logistic regression SMN1 p = 0.54 and SMN2 p = 0.49). In addition, the copy number of SMN did not associate with patient survival (Royston-Parmar; SMN1 p = 0.78 and SMN2 p = 0.23) or age at onset (Royston-Parmar; SMN1 p = 0.75 and SMN2 p = 0.63). INTERPRETATION: In our well-powered study, there was no association of SMN1 or SMN2 copy numbers with the risk of ALS or ALS disease severity. This suggests that changing SMN protein levels in the physiological range may not modify ALS disease course. This is an important finding in the light of emerging therapies targeted at SMN deficiencies. ANN NEUROL 2021;89:686-697.

Primary ovarian endometrioid stromal sarcoma presenting with reno-ureteral colic.

BACKGROUND: Endometrioid Stromal Sarcomas are an infrequent group of mesenchymal tumors that we must take into account in the differential diagnosis despite representing only 0.2% of tumors of the female genital tract, as they can go unnoticed until advanced stages. CASE PRESENTATION: Fifty-fourth year-old woman referred from the Urology department due to incidental finding of adnexal mass in MRI during examination after renoureteral colic, in the case of a 50 mm solid cystic mass in LE. MT were within the normal range, and the CT scan observed this mass in contact with the left ureter. The surgery was completed with hysterectomy and contralateral adnexectomy without incident and chemotherapy treatment was not added. The pathological result was ovarian tissue with low-grade endometrial sarcoma. Currently, after two years of follow-up, the patient remains stable without any recurrence of disease. CONCLUSIONS: Endometrioid stromal sarcomas are rare tumors that originate in the endometrial stroma, the ovarian location being rare. Management lies in surgical treatment, and adjuvant therapy is sometimes necessary in advanced stages.