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1.
Nat Commun ; 15(1): 8412, 2024 Sep 28.
Article in English | MEDLINE | ID: mdl-39333551

ABSTRACT

Cryptic fungal pathogens pose disease management challenges due to their morphological resemblance to known pathogens. Here, we investigated the genomes and phenotypes of 53 globally distributed isolates of Aspergillus section Nidulantes fungi and found 30 clinical isolates-including four isolated from COVID-19 patients-were A. latus, a cryptic pathogen that originated via allodiploid hybridization. Notably, all A. latus isolates were misidentified. A. latus hybrids likely originated via a single hybridization event during the Miocene and harbor substantial genetic diversity. Transcriptome profiling of a clinical isolate revealed that both parental subgenomes are actively expressed and respond to environmental stimuli. Characterizing infection-relevant traits-such as drug resistance and growth under oxidative stress-revealed distinct phenotypic profiles among A. latus hybrids compared to parental and closely related species. Moreover, we identified four features that could aid A. latus taxonomic identification. Together, these findings deepen our understanding of the origin of cryptic pathogens.


Subject(s)
Aspergillus , COVID-19 , Genetic Variation , Genome, Fungal , Phylogeny , Humans , Genome, Fungal/genetics , Aspergillus/genetics , Aspergillus/isolation & purification , COVID-19/virology , COVID-19/epidemiology , SARS-CoV-2/genetics , SARS-CoV-2/isolation & purification , Hybridization, Genetic , Phenotype , Evolution, Molecular , Gene Expression Profiling/methods
2.
mBio ; : e0226424, 2024 Sep 16.
Article in English | MEDLINE | ID: mdl-39283084

ABSTRACT

Sexual reproduction in fungi allows genetic recombination and increases genetic diversity, allowing adaptation and survival. The velvet complex is a fungal-specific protein assembly that regulates development, pathogenesis, and secondary metabolism in response to environmental cues, such as light. In Neurospora crassa, this complex comprises VE-1, VE-2, and LAE-1. Deletion of ve-1 or ve-2, but not lae-1, leads to increased conidiation (asexual spore formation) and reduced sexual development. Mutants lacking ve-1 and/or ve-2 are female sterile and male fertile, indicating that a VE-1/VE-2 complex regulates the development of female structures. During sexual development, we observed differential regulation of 2,117 genes in dark and 4,364 genes in light between the wild type and the ∆ve-1 strain. The pheromone response and cell wall integrity pathways were downregulated in the ∆ve-1 mutant, especially in light. Additionally, we found reduced levels of both total and phosphorylated MAK-1 and MAK-2 kinases. In vitro experiments demonstrated the binding of VE-1 and VE-2 to the promoters of mak-1 and mak-2, suggesting a direct regulatory role of VE-1/VE-2 in the transcriptional control of MAPK genes to regulate sexual development. Deletion of the photosensor gene white-collar 1 prevented the light-dependent inhibition of sexual development in the ∆ve-1 mutant by increasing transcription of the pheromone response and cell wall integrity pathway genes to the levels in the dark. Our results support the proposal that the regulation of the MAP kinase pathways by the VE-1/VE-2 complex is a key element in transcriptional regulation that occurs during sexual development. IMPORTANCE: Sexual reproduction generates new gene combinations and novel phenotypic traits and facilitates evolution. Induction of sexual development in fungi is often regulated by environmental conditions, such as the presence of light and nutrients. The velvet protein complex coordinates internal cues and environmental signals to regulate development. We have found that VE-1, a component of the velvet complex, regulates transcription during sexual development in the fungus Neurospora crassa. VE-1 regulates the transcription of many genes, including those involved in mitogen-activated protein kinase (MAPK) signaling pathways that are essential in the regulation of sexual development, and regulates the activity of the MAPK pathway. Our findings provide valuable insights into how fungi respond to environmental signals and integrate them into their reproductive processes.

4.
Nat Commun ; 15(1): 6066, 2024 Jul 18.
Article in English | MEDLINE | ID: mdl-39025853

ABSTRACT

DNA N6-adenine methylation (6mA) has recently gained importance as an epigenetic modification in eukaryotes. Its function in lineages with high levels, such as early-diverging fungi (EDF), is of particular interest. Here, we investigated the biological significance and evolutionary implications of 6mA in EDF, which exhibit divergent evolutionary patterns in 6mA usage. The analysis of two Mucorales species displaying extreme 6mA usage reveals that species with high 6mA levels show symmetric methylation enriched in highly expressed genes. In contrast, species with low 6mA levels show mostly asymmetric 6mA. Interestingly, transcriptomic regulation throughout development and in response to environmental cues is associated with changes in the 6mA landscape. Furthermore, we identify an EDF-specific methyltransferase, likely originated from endosymbiotic bacteria, as responsible for asymmetric methylation, while an MTA-70 methylation complex performs symmetric methylation. The distinct phenotypes observed in the corresponding mutants reinforced the critical role of both types of 6mA in EDF.


Subject(s)
Adenine , DNA Methylation , Gene Expression Regulation, Fungal , Mucorales , Adenine/metabolism , Mucorales/genetics , Mucorales/metabolism , Epigenesis, Genetic , Fungal Proteins/genetics , Fungal Proteins/metabolism , Phylogeny , Evolution, Molecular , Methyltransferases/metabolism , Methyltransferases/genetics , DNA, Fungal/genetics , DNA, Fungal/metabolism , Mutation
5.
Neurology ; 103(2): e209539, 2024 Jul 23.
Article in English | MEDLINE | ID: mdl-38875516

ABSTRACT

BACKGROUND AND OBJECTIVES: Whether the outcome of patients with spontaneous intracerebral hemorrhage (ICH) differs depending on the type of hospital where they are admitted is uncertain. The objective of this study was to determine influence of hospital type at admission (telestroke center [TSC], primary stroke center [PSC], or comprehensive stroke center [CSC]) on outcome for patients with ICH. We hypothesized that outcomes may be better for patients admitted to a CSC. METHODS: This is a multicenter prospective observational and population-based study of a cohort of consecutively recruited patients with ICH (March 2020-March 2022). We included all patients with spontaneous ICH in Catalonia (Spain) who had a pre-ICH modified Rankin scale (mRS) score of 0-3 and who were admitted to the hospital within 24 hours of onset. We compared patients admitted to a TSC/PSC (n = 641) or a CSC (n = 1,320) and also analyzed the subgroup of patients transferred (n = 331) or not transferred (n = 310) from a TSC/PSC to a CSC. The main outcome was the 3-month mRS score obtained by blinded investigators. Outcomes were compared using adjusted ordinal logistic regression to estimate the common odds ratio (OR) and 95% CI for a shift in mRS scores. A propensity score matching (PSM) analysis was performed for the subgroup of transferred patients. RESULTS: Relevant data were obtained from 1961 of a total of 2,230 patients, with the mean (SD) age of 70 (14.1) years, and 713 (38%) patients were women. After adjusting for confounders (age, NIH Stroke Scale score, intraventricular hemorrhage, hematoma volume, and pre-ICH mRS score), type of hospital of initial admission (CSC vs TSC/PSC) was not associated with outcome (adjusted common OR 1.13, 95% CI 0.93-1.38). A PSM analysis indicated that transfer to a CSC was not associated with more favorable outcomes (OR 0.77, 95% CI 0.55-1.10; p = 0.16). DISCUSSION: In this population-based study, we found that, after adjusting for confounders, hospital types were not associated with functional outcomes. In addition, for patients who were transferred from a TSC/PSC to a CSC, PSM indicated that outcomes were similar to nontransferred patients. Our findings suggest that patient characteristics are more important than hospital characteristics in determining outcome after ICH. TRIAL REGISTRATION INFORMATION: ClinicalTrials.gov Identifier: NCT03956485.


Subject(s)
Cerebral Hemorrhage , Humans , Female , Male , Aged , Cerebral Hemorrhage/epidemiology , Middle Aged , Prospective Studies , Spain/epidemiology , Aged, 80 and over , Treatment Outcome , Hospitals/statistics & numerical data , Hospitalization/statistics & numerical data
6.
J Neurointerv Surg ; 16(2): 143-150, 2024 Jan 12.
Article in English | MEDLINE | ID: mdl-37068936

ABSTRACT

BACKGROUND: The influence of vascular imaging acquisition on workflows at local stroke centers (LSCs) not capable of performing thrombectomy in patients with a suspected large vessel occlusion (LVO) stroke remains uncertain. We analyzed the impact of performing vascular imaging (VI+) or not (VI- at LSC arrival on variables related to workflows using data from the RACECAT Trial. OBJECTIVE: To compare workflows at the LSC among patients enrolled in the RACECAT Trial with or without VI acquisition. METHODS: We included patients with a diagnosis of ischemic stroke who were enrolled in the RACECAT Trial, a cluster-randomized trial that compared drip-n-ship versus mothership triage paradigms in patients with suspected acute LVO stroke allocated at the LSC. Outcome measures included time metrics related to workflows and the rate of interhospital transfers and thrombectomy among transferred patients. RESULTS: Among 467 patients allocated to a LSC, vascular imaging was acquired in 277 patients (59%), of whom 198 (71%) had a LVO. As compared with patients without vascular imaging, patients in the VI+ group were transferred less frequently as thrombectomy candidates to a thrombectomy-capable center (58% vs 74%, P=0.004), without significant differences in door-indoor-out time at the LSC (median minutes, VI+ 78 (IQR 69-96) vs VI- 76 (IQR 59-98), P=0.6). Among transferred patients, the VI+ group had higher rate of thrombectomy (69% vs 55%, P=0.016) and shorter door to puncture time (median minutes, VI+ 41 (IQR 26-53) vs VI- 54 (IQR 40-70), P<0.001). CONCLUSION: Among patients with a suspected LVO stroke initially evaluated at a LSC, vascular imaging acquisition might improve workflow times at thrombectomy-capable centers and reduce the rate of futile interhospital transfers. These results deserve further evaluation and should be replicated in other settings and geographies.


Subject(s)
Arterial Occlusive Diseases , Brain Ischemia , Endovascular Procedures , Ischemic Stroke , Stroke , Humans , Brain Ischemia/drug therapy , Stroke/diagnostic imaging , Stroke/surgery , Thrombectomy , Thrombolytic Therapy , Treatment Outcome , Workflow
7.
bioRxiv ; 2023 Jul 03.
Article in English | MEDLINE | ID: mdl-37461539

ABSTRACT

Cryptic fungal pathogens pose significant identification and disease management challenges due to their morphological resemblance to known pathogenic species while harboring genetic and (often) infectionrelevant trait differences. The cryptic fungal pathogen Aspergillus latus, an allodiploid hybrid originating from Aspergillus spinulosporus and an unknown close relative of Aspergillus quadrilineatus within section Nidulantes, remains poorly understood. The absence of accurate diagnostics for A. latus has led to misidentifications, hindering epidemiological studies and the design of effective treatment plans. We conducted an in-depth investigation of the genomes and phenotypes of 44 globally distributed isolates (41 clinical isolates and three type strains) from Aspergillus section Nidulantes. We found that 21 clinical isolates were A. latus; notably, standard methods of pathogen identification misidentified all A. latus isolates. The remaining isolates were identified as A. spinulosporus (8), A. quadrilineatus (1), or A. nidulans (11). Phylogenomic analyses shed light on the origin of A. latus, indicating one or two hybridization events gave rise to the species during the Miocene, approximately 15.4 to 8.8 million years ago. Characterizing the A. latus pangenome uncovered substantial genetic diversity within gene families and biosynthetic gene clusters. Transcriptomic analysis revealed that both parental genomes are actively expressed in nearly equal proportions and respond to environmental stimuli. Further investigation into infection-relevant chemical and physiological traits, including drug resistance profiles, growth under oxidative stress conditions, and secondary metabolite biosynthesis, highlight distinct phenotypic profiles of the hybrid A. latus compared to its parental and closely related species. Leveraging our comprehensive genomic and phenotypic analyses, we propose five genomic and phenotypic markers as diagnostics for A. latus species identification. These findings provide valuable insights into the evolutionary origin, genomic outcome, and phenotypic implications of hybridization in a cryptic fungal pathogen, thus enhancing our understanding of the underlying processes contributing to fungal pathogenesis. Furthermore, our study underscores the effectiveness of extensive genomic and phenotypic analyses as a promising approach for developing diagnostics applicable to future investigations of cryptic and emerging pathogens.

8.
Eur Stroke J ; 8(2): 557-565, 2023 06.
Article in English | MEDLINE | ID: mdl-37231687

ABSTRACT

INTRODUCTION: Previous studies have reported differences in the management and outcome of women stroke patients in comparison with men. We aim to analyze sex and gender differences in the medical assistance, access to treatment and outcome of acute stroke patients in Catalonia. PATIENTS AND METHODS: Data were obtained from a prospective population-based registry of stroke code activations in Catalonia (CICAT) from January/2016 to December/2019. The registry includes demographic data, stroke severity, stroke subtype, reperfusion therapy, and time workflow. Centralized clinical outcome at 90 days was assessed in patients receiving reperfusion therapy. RESULTS: A total of 23,371 stroke code activations were registered (54% men, 46% women). No differences in prehospital time metrics were observed. Women more frequently had a final diagnosis of stroke mimic, were older and had a previous worse functional situation. Among ischemic stroke patients, women had higher stroke severity and more frequently presented proximal large vessel occlusion. Women received more frequently reperfusion therapy (48.2% vs 43.1%, p < 0.001). Women tended to present a worse outcome at 90 days, especially for the group receiving only IVT (good outcome 56.7% vs 63.8%; p < 0.001), but not for the group of patients treated with IVT + MT or MT alone, although sex was not independently associated with clinical outcome in logistic regression analysis (OR 1.07; 95% CI, 0.94-1.23; p = 0.27) nor in the analysis after matching using the propensity score (OR 1.09; 95% CI, 0.97-1.22). DISCUSSION AND CONCLUSION: We found some differences by sex in that acute stroke was more frequent in older women and the stroke severity was higher. We found no differences in medical assistance times, access to reperfusion treatment and early complications. Worse clinical outcome at 90 days in women was conditioned by stroke severity and older age, but not by sex itself.


Subject(s)
Stroke , Male , Humans , Female , Aged , Spain/epidemiology , Prospective Studies , Sex Factors , Stroke/diagnosis , Treatment Outcome
9.
Int J Stroke ; 18(2): 229-236, 2023 02.
Article in English | MEDLINE | ID: mdl-35373657

ABSTRACT

BACKGROUND: Acute ischemic stroke patients not referred directly to a comprehensive stroke center (CSC) have reduced access to endovascular treatment (EVT). The RACECAT trial is a population-based cluster-randomized trial, designed to compare mothership and drip-and-ship strategies in acute ischemic stroke patients outside the catchment area of a CSC. AIMS: To analyze the evolution of performance indicators in the regions that participated in RACECAT. METHODS: This retrospective longitudinal observational study included all stroke alerts evaluated by emergency medical services in Catalonia between February 2016 and February 2020. Cases were classified geographically according to the nearest SC: local SC (Local-SC) and CSC catchment areas. We analyzed the evolution of EVT rates and relevant workflow times in Local-SC versus CSC catchment areas over three study periods: P1 (February 2016 to April 2017: before RACECAT initiation), P2 (May 2017 to September 2018), and P3 (October 2018 to February 2020). RESULTS: We included 20603 stroke alerts, 10,694 (51.9%) of which were activated within Local-SC catchment areas. The proportion of patients receiving EVT within Local-SC catchment areas increased (P1 vs. P3: 7.5% (95% confidence interval (CI), 6.4-8.7) to 22.5% (95% CI, 20.8-24.4) p < 0.001). Inequalities in the odds of receiving EVT were reduced for patients from CSC versus Local-SC catchment areas (P1: odds ratio (OR) 3.9 (95% CI, 3.2-5) vs. P3: OR 1.5 (95% CI, 1.3-1.7) In Local-SC, door-to-image (P1: 24 (interquartile range (IQR) 15-36), P2: 24 (15-35), P3: 21 (13-32) min, p < 0.001) and door-to-needle times (P1: 42 (31-60), P2: 41 (29-58), P3: 35 (25-50) p < 0.001) reduced. Time from Local-SC arrival to groin puncture also decreased over time (P1: 188 [151-229], P2: 190 (157-233), P3: 168 (127-215) min, p < 0.001). CONCLUSION: An increase in EVT rates in Local-SC regions with a significant decrease in workflow times occurred during the period of the RACECAT trial.


Subject(s)
Brain Ischemia , Endovascular Procedures , Ischemic Stroke , Stroke , Humans , Stroke/epidemiology , Stroke/therapy , Brain Ischemia/therapy , Thrombolytic Therapy/methods , Quality Indicators, Health Care , Retrospective Studies , Treatment Outcome , Thrombectomy
10.
Int J Stroke ; 18(2): 221-228, 2023 02.
Article in English | MEDLINE | ID: mdl-35272563

ABSTRACT

BACKGROUND: The first pass effect (FPE) is an independent predictor of functional independence in patients with large vessel occlusion in anterior circulation ischemic strokes. However, whether it predicts outcome in posterior circulation large vessel occlusion (PC-LVO) is uncertain. We aimed to study the frequency, characteristics, and predictors of FPE and its association with clinical outcomes in PC-LVO. METHOD: We performed an analysis from the prospective CICAT Registry. All patients with PC-LVO who underwent endovascular therapy between January 2016 and January 2020 were included. A centrally assessed clinical follow-up was performed at 3 months by blinded investigators. FPE was defined as the achievement of modified Thrombolysis In Cerebral Infarction 3 in a single pass of the endovascular thrombectomy device, and multi-pass effect (MPE) if it was achieved in more than one pass. A multivariable analysis was performed to identify whether FPE is an independent predictor of functional independence defined as a modified Rankin Score of 0-2. RESULTS: We analyzed data from 265 patients in who FPE was achieved in 105 (39.6%). Patients with FPE were more likely to achieve functional independence compared to the non-FPE group (52.4% vs 25.1%, p < .001) and the MPE group (52.4% vs 26.7%, p < .001). FPE was independently associated with functional independence (adjusted odds ratio (aOR): 2.10, 95% confidence interval (CI) 1.01-4.37) but MPE was not (aOR: 0.92, 95% CI 0.40-2.13). Independent predictors of FPE were the use of direct aspiration, embolic mechanism of stroke, and the absence of general anesthesia (GA) use. CONCLUSIONS: FPE is an independent predictor of functional independence in PC-LVO and was associated with a significantly better outcome than MPE.


Subject(s)
Brain Ischemia , Endovascular Procedures , Stroke , Humans , Stroke/therapy , Stroke/etiology , Prospective Studies , Treatment Outcome , Thrombectomy , Registries , Retrospective Studies , Brain Ischemia/therapy , Brain Ischemia/etiology , Endovascular Procedures/adverse effects
11.
Stroke ; 53(11): 3289-3294, 2022 11.
Article in English | MEDLINE | ID: mdl-35946402

ABSTRACT

BACKGROUND: We analyzed the main factors associated with intravenous thrombolysis (IVT) in patients with minor ischemic stroke. METHODS: Data were obtained from a prospective, government-mandated, population-based registry of stroke code patients in Catalonia (6 Comprehensive Stroke Centers, 8 Primary Stroke Centers, and 14 TeleStroke Centers). We selected patients diagnosed with ischemic stroke and National Institutes of Health Stroke Scale (NIHSS) ≤5 at hospital admission from January 2016 to December 2020. We excluded patients with a baseline modified Rankin Scale score of ≥3, absolute contraindication for IVT, unknown stroke onset, or admitted to hospital beyond 4.5 after stroke onset. The main outcome was treatment with IVT. We performed univariable and binary logistic regression analyses to identify the most important factors associated with IVT. RESULTS: We included 2975 code strokes; 1433 (48.2%) received IVT of which 30 (2.1%) had a symptomatic hemorrhagic transformation. Patients treated with IVT as compared to patients who did not receive IVT were more frequently women, had higher NIHSS, arrived earlier to hospital, were admitted to a Comprehensive Stroke Centers, and had large vessel occlusion. After binary logistic regression, NIHSS score 4 to 5 (odds ratio, 40.62 [95% CI, 31.73-57.22]; P<0.001) and large vessel occlusion (odds ratio, 16.39 [95% CI, 7.25-37.04]; P<0.001) were the strongest predictors of IVT. Younger age, female sex, baseline modified Rankin Scale score of 0, earlier arrival to hospital (<120 minutes after stroke onset), and the type of stroke center were also independently associated with IVT. The weight of large vessel occlusion on IVT was higher in patients with lower NIHSS. CONCLUSIONS: Minor stroke female patients, with higher NIHSS, arriving earlier to the hospital, presenting with large vessel occlusion and admitted to a Comprehensive Stroke Centers were more likely to receive intravenous thrombolysis.


Subject(s)
Brain Ischemia , Ischemic Stroke , Stroke , Female , Humans , Brain Ischemia/therapy , Prospective Studies , Treatment Outcome , Stroke/drug therapy , Stroke/epidemiology , Stroke/complications , Thrombolytic Therapy , Thrombectomy , Fibrinolytic Agents/therapeutic use
12.
mBio ; 13(4): e0150522, 2022 08 30.
Article in English | MEDLINE | ID: mdl-35913159

ABSTRACT

Asexual reproduction in fungi facilitates the dispersal and colonization of new substrates and, in pathogenic fungi, allows infection of plants and animals. The velvet complex is a fungus-specific protein complex that participates in the regulation of gene expression in response to environmental signals like light, as well as developmental processes, pathogenesis, and secondary metabolism. The velvet complex in the fungus Neurospora crassa is composed of three proteins, VE-1, VE-2, and LAE-1. Mutations in ve-1 or ve-2, but not in lae-1, led to shorter heights of aerial tissue, a mixture of aerial hyphae and developing macroconidia, and increased microconidiation when they were combined with mutations in the transcription factor gene fl. VE-2 and LAE-1 were detected during vegetative growth and conidiation, unlike VE-1, which was mostly observed in samples obtained from submerged vegetative hyphae. We propose that VE-1 is the limiting component of the velvet complex during conidiation and has a major role in the transcriptional regulation of conidiation. Characterization of the role of VE-1 during mycelial growth and asexual development (conidiation) by transcriptome sequencing (RNA-seq) experiments allowed the identification of a set of genes regulated by VE-1 that participate in the regulation of conidiation, most notably the transcription factor genes vib-1 and fl. We propose that VE-1 and VE-2 regulate the development of aerial tissue and the balance between macro- and microconidiation in coordination with FL and VIB-1. IMPORTANCE Most fungi disperse in nature and infect new hosts by producing vegetative spores or conidia during asexual development. This is a process that is regulated by environmental signals like light and the availability of nutrients. A protein complex, the velvet complex, participates in the integration of environmental signals to regulate conidiation. We have found that a key component of this complex in the fungus Neurospora crassa, VE-1, has a major role in the regulation of transcription during conidiation. VE-1 regulates a large number of genes, including the genes for the transcription factors FL and VIB-1. Our results will help to understand how environmental signals are integrated in the fungal cell to regulate development.


Subject(s)
Neurospora crassa , Animals , Fungal Proteins/genetics , Fungal Proteins/metabolism , Gene Expression Regulation, Fungal , Neurospora crassa/metabolism , Spores, Fungal , Transcription Factors/genetics , Transcription Factors/metabolism
13.
J Fungi (Basel) ; 8(8)2022 Jul 22.
Article in English | MEDLINE | ID: mdl-35893127

ABSTRACT

Polarized growth is a defining property of filamentous fungi, which plays an important role in different aspects of their biology, including virulence. However, little information is available about the determinants of cell surface organization and their role in polarized growth. The fungal protein MesA was identified in a genetic screen in Aspergillus nidulans and is involved in the stabilization of the polarity axes, but it has no evident role in budding yeast. In this work, I present evidence that in the dimorphic fungal phytopathogen Ustilago maydis MesA/Mes1 is involved in cell wall stability and polarized growth. mes1 mutants were more sensitive to drugs provoking cell wall stress, and they displayed a temperature-sensitive phenotype. Actin cytoskeleton was disorganized in a mes1 mutant, suggesting that there is a connection between Mes1, the actin cytoskeleton and polarized morphogenesis. The septin ring was also absent from the bud tip, but not the bud neck. Deletion of mes1 provoked defects in endocytosis and vacuolar organization in the cells. Mes1 was essential for strong polarized growth in the hyphal form, but it was dispensable during low or moderate polarized growth in the yeast form in U. maydis at a permissive temperature. Consistently, mes1 mutants showed delayed mating and they were avirulent.

14.
BMC Biol ; 20(1): 149, 2022 06 27.
Article in English | MEDLINE | ID: mdl-35761233

ABSTRACT

BACKGROUND: Fungi use light as an environmental signal to regulate developmental transitions that are key aspects of their biological cycles and that are also relevant for their dispersal and infectivity as plant or animal pathogens. In addition, light regulates the accumulation of photoprotective pigments, like carotenoids, and other secondary metabolites. Most fungal light responses occur after changes in gene transcription and we describe here a novel effect of light in the regulation of degradation of VE-1, a key component of the velvet complex, in the model fungus Neurospora crassa. The velvet complex is a fungal-specific protein complex that coordinates fungal development, secondary metabolism, and light regulation by interacting with other regulators and photoreceptors and modifying gene expression. RESULTS: We have characterized the role of VE-1 during conidiation in N. crassa. In vegetative mycelia, VE-1 is localized in the cytoplasm and nuclei and is required for light-dependent transcription but does not interact with the photoreceptor and transcription factor WC-1. VE-1 is more stable in light than in darkness during asexual development (conidiation). We have shown that this light effect requires the blue-light photoreceptor WC-1. We have characterized the role of the proteasome, the COP9 signalosome (CSN), and the adaptor component of cullin-RING ubiquitin ligases, FWD-1, in the degradation of VE-1. CONCLUSIONS: We propose that this new effect of light allows the fungal cell to adapt quickly to changes in light exposure by promoting the accumulation of VE-1 for the regulation of genes that participate in the biosynthesis of photoprotective pigments.


Subject(s)
Neurospora crassa , Animals , Cell Nucleus/metabolism , Fungal Proteins/genetics , Fungal Proteins/metabolism , Gene Expression Regulation, Fungal , Neurospora crassa/metabolism , Secondary Metabolism , Transcription Factors/genetics
15.
Biochimie ; 198: 48-59, 2022 Jul.
Article in English | MEDLINE | ID: mdl-35307483

ABSTRACT

Bacillus sp. HR21-6 is capable of the chemo- and regioselective synthesis of lipophilic partially acetylated phenolic compounds derived from olive polyphenols, which are powerful antioxidants important in the formulation of functional foods. In this work, an acetyl esterase was identified in the secretome of this strain by non-targeted proteomics, and classified in the GDSL family (superfamily SGNH). The recombinant protein was expressed and purified from Escherichia coli in the soluble form, and biochemically characterized. Site-directed mutagenesis was performed to understand the role of different amino acids that are conserved among GDSL superfamily of esterases. Mutation of Ser-10, Gly-45 or His-185 abolished the enzyme activity, while mutation of Asn-77 or Thr-184 altered the substrate specificity of the enzyme. This new enzyme is able to perform chemoselective conversions of olive phenolic compounds with great interest in the food industry, such as hydroxytyrosol, 3,4-dihydroxyphenylglycol, and oleuropein.


Subject(s)
Acetylesterase , Bacillus , Bacterial Proteins , Acetylesterase/chemistry , Acetylesterase/genetics , Amino Acid Sequence/genetics , Bacillus/enzymology , Bacillus/genetics , Bacterial Proteins/chemistry , Bacterial Proteins/genetics , Escherichia coli , Esterases/metabolism , Mutagenesis, Site-Directed , Substrate Specificity/genetics
16.
Stroke ; 53(3): 845-854, 2022 03.
Article in English | MEDLINE | ID: mdl-34702065

ABSTRACT

BACKGROUND AND PURPOSE: Mechanical thrombectomy (MT) in ischemic stroke patients with poor prestroke conditions remains controversial. We aimed to analyze the frequency of previously disabled patients treated with MT in clinical practice, the safety and clinical response to MT of patients with preexisting disability, and the disabled patient characteristics associated with a better response to MT. METHODS: We studied all consecutive patients with anterior circulation occlusion treated with MT from January 2017 to December 2019 included in the Codi Ictus Catalunya registry-a government-mandated, prospective, hospital-based data set. Prestroke disability was defined as modified Rankin Scale score 2 or 3. Functional outcome at 90 days was centrally assessed by a blinded evaluator of the Catalan Stroke Program. Favorable outcome (to return at least to prestroke modified Rankin Scale at 90 days) and safety and secondary outcomes were compared with patients without previous disability. Logistic regression analysis was used to assess the association between prestroke disability and outcomes and to identify a disabled patient profile with favorable outcome after MT. RESULTS: Of 2487 patients included in the study, 409 (17.1%) had prestroke disability (313 modified Rankin Scale score 2 and 96 modified Rankin Scale score 3). After adjustment for covariates, prestroke disability was not associated with a lower chance of achieving favorable outcome at 90 days (24% versus 30%; odds ratio, 0.79 [0.57-1.08]), whereas it was independently associated with a higher risk of symptomatic intracranial hemorrhage (5% versus 3%; odds ratio, 2.04 [1.11-3.72]) and long-term mortality (31% versus 18%; odds ratio, 1.74 [1.27-2.39]) compared with patients without disability. Prestroke disabled patients without diabetes, Alberta Stroke Program Early CT Score >8 and National Institutes of Health Stroke Scale score <17 showed similar safety and outcome results after MT as patients without prestroke disability. CONCLUSIONS: Despite a higher mortality and risk of symptomatic intracranial hemorrhage, prestroke-disabled patients return as often as independent patients to their prestroke level of function, especially those nondiabetic patients with favorable early ischemic signs profile. These data support a potential benefit of MT in patients with previous mild or moderate disability after large anterior vessel occlusion stroke.


Subject(s)
Disabled Persons , Ischemic Stroke/surgery , Registries , Thrombectomy , Aged , Aged, 80 and over , Female , Humans , Male , Middle Aged , Prospective Studies , Spain
17.
J Stroke ; 23(3): 401-410, 2021 Sep.
Article in English | MEDLINE | ID: mdl-34649384

ABSTRACT

BACKGROUND AND PURPOSE:  In real-world practice, the benefit of mechanical thrombectomy (MT) is uncertain in stroke patients with very favorable or poor prognostic profiles at baseline. We studied the effectiveness of MT versus medical treatment stratifying by different baseline prognostic factors. METHODS:  Retrospective analysis of 2,588 patients with an ischemic stroke due to large vessel occlusion nested in the population-based registry of stroke code activations in Catalonia from January 2017 to June 2019. The effect of MT on good functional outcome (modified Rankin Score ≤2) and survival at 3 months was studied using inverse probability of treatment weighting (IPTW) analysis in three pre-defined baseline prognostic groups: poor (if pre-stroke disability, age >85 years, National Institutes of Health Stroke Scale [NIHSS] >25, time from onset >6 hours, Alberta Stroke Program Early CT Score <6, proximal vertebrobasilar occlusion, supratherapeutic international normalized ratio >3), good (if NIHSS <6 or distal occlusion, in the absence of poor prognostic factors), or reference (not meeting other groups' criteria). RESULTS:  Patients receiving MT (n=1,996, 77%) were younger, had less pre-stroke disability, and received systemic thrombolysis less frequently. These differences were balanced after the IPTW stratified by prognosis. MT was associated with good functional outcome in the reference (odds ratio [OR], 2.9; 95% confidence interval [CI], 2.0 to 4.4), and especially in the poor baseline prognostic stratum (OR, 3.9; 95% CI, 2.6 to 5.9), but not in the good prognostic stratum. MT was associated with survival only in the poor prognostic stratum (OR, 2.6; 95% CI, 2.0 to 3.3). CONCLUSIONS:  Despite their worse overall outcomes, the impact of thrombectomy over medical management was more substantial in patients with poorer baseline prognostic factors than patients with good prognostic factors.

18.
Environ Microbiol ; 23(11): 6924-6939, 2021 11.
Article in English | MEDLINE | ID: mdl-34448331

ABSTRACT

Nitric oxide (NO) is a signalling molecule in eukaryotic and prokaryotic organisms. NO levels transiently boost upon induction of conidiation in Aspergillus nidulans. Only one pathway for NO synthesis involving nitrate reductase has been reported in filamentous fungi so far, but this does not satisfy all the NO produced in fungal cells. Here we provide evidence for at least one additional biosynthetic pathway in A. nidulans involving l-arginine or an intermediate metabolite as a substrate. Under certain growth conditions, the addition of l-arginine to liquid media elicited a burst of NO that was not dependent on any of the urea cycle genes. The NO levels were controlled by the metabolically available arginine, which was regulated by mobilization from the vacuoles and during development. In vitro assays with protein extracts and amino acid profiling strongly suggested the existence of an arginine-dependent NO pathway analogous to the mammalian NO synthase. Addition of polyamines induced NO synthesis, and mutations in the polyamine synthesis genes puA and spdA reduced the production of NO. In conclusion, here we report an additional pathway for the synthesis of NO in A. nidulans using urea cycle intermediates.


Subject(s)
Aspergillus nidulans , Animals , Arginine/metabolism , Aspergillus nidulans/genetics , Aspergillus nidulans/metabolism , Mammals/metabolism , Nitrate Reductase/metabolism , Nitric Oxide/metabolism
19.
Cerebrovasc Dis ; 50(5): 551-559, 2021.
Article in English | MEDLINE | ID: mdl-34023822

ABSTRACT

INTRODUCTION: The COVID-19 pandemic resulted in significant healthcare reorganizations, potentially striking standard medical care. We investigated the impact of the COVID-19 pandemic on acute stroke care quality and clinical outcomes to detect healthcare system's bottlenecks from a territorial point of view. METHODS: Crossed-data analysis between a prospective nation-based mandatory registry of acute stroke, Emergency Medical System (EMS) records, and daily incidence of COVID-19 in Catalonia (Spain). We included all stroke code activations during the pandemic (March 15-May 2, 2020) and an immediate prepandemic period (January 26-March 14, 2020). Primary outcomes were stroke code activations and reperfusion therapies in both periods. Secondary outcomes included clinical characteristics, workflow metrics, differences across types of stroke centers, correlation analysis between weekly EMS alerts, COVID-19 cases, and workflow metrics, and impact on mortality and clinical outcome at 90 days. RESULTS: Stroke code activations decreased by 22% and reperfusion therapies dropped by 29% during the pandemic period, with no differences in age, stroke severity, or large vessel occlusion. Calls to EMS were handled 42 min later, and time from onset to hospital arrival increased by 53 min, with significant correlations between weekly COVID-19 cases and more EMS calls (rho = 0.81), less stroke code activations (rho = -0.37), and longer prehospital delays (rho = 0.25). Telestroke centers were afflicted with higher reductions in stroke code activations, reperfusion treatments, referrals to endovascular centers, and increased delays to thrombolytics. The independent odds of death increased (OR 1.6 [1.05-2.4], p 0.03) and good functional outcome decreased (mRS ≤2 at 90 days: OR 0.6 [0.4-0.9], p 0.015) during the pandemic period. CONCLUSION: During the COVID-19 pandemic, Catalonia's stroke system's weakest points were the delay to EMS alert and a decline of stroke code activations, reperfusion treatments, and interhospital transfers, mostly at local centers. Patients suffering an acute stroke during the pandemic period had higher odds of poor functional outcome and death. The complete stroke care system's analysis is crucial to allocate resources appropriately.


Subject(s)
Emergency Medical Services , Fibrinolytic Agents/pharmacology , SARS-CoV-2/pathogenicity , Stroke/virology , Humans , Prospective Studies , Spain/epidemiology , Stroke/diagnosis , Thrombolytic Therapy/methods , Time-to-Treatment
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