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1.
BMC Biol ; 20(1): 149, 2022 06 27.
Artículo en Inglés | MEDLINE | ID: mdl-35761233

RESUMEN

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.


Asunto(s)
Neurospora crassa , Animales , Núcleo Celular/metabolismo , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Regulación Fúngica de la Expresión Génica , Neurospora crassa/metabolismo , Metabolismo Secundario , Factores de Transcripción/genética
2.
Stroke ; 53(3): 845-854, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-34702065

RESUMEN

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.


Asunto(s)
Personas con Discapacidad , Accidente Cerebrovascular Isquémico/cirugía , Sistema de Registros , Trombectomía , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , España
3.
Stroke ; 53(11): 3289-3294, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-35946402

RESUMEN

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.


Asunto(s)
Isquemia Encefálica , Accidente Cerebrovascular Isquémico , Accidente Cerebrovascular , Femenino , Humanos , Isquemia Encefálica/terapia , Estudios Prospectivos , Resultado del Tratamiento , Accidente Cerebrovascular/tratamiento farmacológico , Accidente Cerebrovascular/epidemiología , Accidente Cerebrovascular/complicaciones , Terapia Trombolítica , Trombectomía , Fibrinolíticos/uso terapéutico
4.
Environ Microbiol ; 23(11): 6924-6939, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34448331

RESUMEN

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.


Asunto(s)
Aspergillus nidulans , Animales , Arginina/metabolismo , Aspergillus nidulans/genética , Aspergillus nidulans/metabolismo , Mamíferos/metabolismo , Nitrato-Reductasa/metabolismo , Óxido Nítrico/metabolismo
5.
Cerebrovasc Dis ; 50(5): 551-559, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34023822

RESUMEN

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.


Asunto(s)
Servicios Médicos de Urgencia , Fibrinolíticos/farmacología , SARS-CoV-2/patogenicidad , Accidente Cerebrovascular/virología , Humanos , Estudios Prospectivos , España/epidemiología , Accidente Cerebrovascular/diagnóstico , Terapia Trombolítica/métodos , Tiempo de Tratamiento
6.
Fungal Genet Biol ; 137: 103337, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-31991229

RESUMEN

Nitric oxide (NO) can be biologically synthesized from nitrite or from arginine. Although NO is involved as a signal in many biological processes in bacteria, plants, and mammals, still little is known about the role of NO in fungi. Here we show that NO levels are regulated by light as an environmental signal in Aspergillus nidulans. The flavohaemoglobin-encoding fhbB gene involved in NO oxidation to nitrate, and the arginine-regulated arginase encoded by agaA, which controls the intracellular concentration of arginine, are both up-regulated by light. The phytochrome fphA is required for the light-dependent induction of fhbB and agaA, while the white-collar gene lreA acts as a repressor when arginine is present in the media. The intracellular arginine pools increase upon induction of both developmental programs (conidiation and sexual development), and the increase is higher under conditions promoting sexual development. The presence of low concentrations of arginine does not affect the light-dependent regulation of conidiation, but high concentrations of arginine overrun the light signal. Deletion of fhbB results in the partial loss of the light regulation of conidiation on arginine and on nitrate media, while deletion of fhbA only affects the light regulation of conidiation on nitrate media. Our working model considers a cross-talk between environmental cues and intracellular signals to regulate fungal reproduction.


Asunto(s)
Aspergillus nidulans/metabolismo , Óxido Nítrico/metabolismo , Reproducción Asexuada/fisiología , Aspergillus/genética , Aspergillus/metabolismo , Aspergillus nidulans/genética , Proteínas Fúngicas/genética , Regulación Fúngica de la Expresión Génica/genética , Genes Fúngicos/genética , Homeostasis , Luz , Esporas Fúngicas/crecimiento & desarrollo , Activación Transcripcional/genética
7.
Appl Environ Microbiol ; 86(7)2020 03 18.
Artículo en Inglés | MEDLINE | ID: mdl-32005734

RESUMEN

Aspergillus fumigatus is a major cause of human disease. The survival of this fungus is dependent on the cell wall organization and function of its components. The cell wall integrity pathway (CWIP) is the primary signaling cascade that controls de novo synthesis of the cell wall in fungi. Abundant conidiation is a hallmark in A. fumigatus, and uptake of conidia by a susceptible host is usually the initial event in infection. The formation of conidia is mediated by the development of fungus-specific specialized structures, conidiophores, which are accompanied by cell wall remodeling. The molecular regulation of these changes in cell wall composition required for the rise of conidiophore from the solid surface and to disperse the conidia into the air is currently unknown. Here, we investigated the role of CWIP in conidiation. We show that CWIP pkcAG579R, ΔmpkA, and ΔrlmA mutants displayed reduced conidiation during synchronized asexual differentiation. The transcription factor RlmA directly regulated the expression of regulators of conidiation, including flbB, flbC, brlA, abaA, and rasB, as well as genes involved in cell wall synthesis and remodeling, and this affected the chitin content in aerial hyphae. Phosphorylation of RlmA and MpkA was increased during asexual differentiation. We also observed that MpkA physically associated with the proteins FlbB, FlbC, BrlA, and RasB during this process, suggesting another level of cross talk between the CWIP and asexual development pathways. In summary, our results support the conclusion that one function of the CWIP is the regulation of asexual development in filamentous fungi.IMPORTANCE A remarkable feature of the human pathogen Aspergillus fumigatus is its ability to produce impressive amounts of infectious propagules known as conidia. These particles reach immunocompromised patients and may initiate a life-threatening mycosis. The conidiation process in Aspergillus is governed by a sequence of proteins that coordinate the development of conidiophores. This process requires the remodeling of the cell wall so that the conidiophores can rise and withstand the chains of conidia. The events regulating cell wall remodeling during conidiation are currently unknown. Here, we show that the cell wall integrity pathway (CWIP) components RlmA and MpkA directly contribute to the activation of the conidiation cascade by enabling transcription or phosphorylation of critical proteins involved in asexual development. This study points to an essential role for the CWIP during conidiation and provides further insights into the complex regulation of asexual development in filamentous fungi.


Asunto(s)
Aspergillus fumigatus/fisiología , Pared Celular/metabolismo , Proteínas Fúngicas/metabolismo , Reproducción Asexuada , Transducción de Señal , Esporas Fúngicas/crecimiento & desarrollo , Aspergilosis/microbiología , Aspergillus fumigatus/crecimiento & desarrollo , Proteínas Fúngicas/genética , Humanos
8.
Epilepsia ; 61(10): 2244-2253, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32857458

RESUMEN

OBJECTIVE: Blood biomarkers have not been widely investigated in poststroke epilepsy. In this study, we aimed to describe clinical factors and biomarkers present during acute stroke and analyze their association with the development of epilepsy at long term. METHODS: A panel of 14 blood biomarkers was evaluated in patients with ischemic and hemorrhagic stroke. Biomarkers were normalized and standardized using Z-scores. Stroke and epilepsy-related variables were also assessed: stroke severity, determined by National Institutes of Health Stroke Scale (NIHSS) score, stroke type and cause, time from stroke to onset of late seizures, and type of seizure. Multiple Cox regression models were used to identify clinical variables and biomarkers independently associated with epilepsy. RESULTS: From a cohort of 1115 patients, 895 patients were included. Mean ± standard deviation (SD) age was 72.0 ± 13.1 years, and 57.8% of patients were men. Fifty-one patients (5.7%) developed late seizures, with a median time to onset of 232 days (interquartile range [IQR] 86-491). NIHSS score ≥8 (P < .001, hazard ratio [HR] 4.013, 95% confidence interval [CI] 2.123-7.586) and a history of early onset seizures (P < .001, HR 4.038, 95% CI 1.802-9.045) were factors independently associated with a risk of developing epilepsy. Independent blood biomarkers predictive of epilepsy were high endostatin levels >1.203 (P = .046, HR 4.300, 95% CI 1.028-17.996) and low levels of heat shock 70 kDa protein-8 (Hsc70) <2.496 (P = .006, HR 3.795, 95% CI 1.476-9.760) and S100B <1.364 (P = .001, HR 2.955, 95% CI 1.534-5.491). The risk of epilepsy when these biomarkers were combined increased to 17%. The area under the receiver-operating characteristic (ROC) curve of the predictive model was stronger when clinical variables were combined with blood biomarkers (74.3%, 95% CI 65.2%-83.3%) than when they were used alone (68.9%, 95% CI 60.3%-77.6%). SIGNIFICANCE: Downregulated S100B and Hsc70 and upregulated endostatin may assist in prediction of poststroke epilepsy and may provide additional information to clinical risk factors. In addition, these data are hypothesis-generating for the epileptogenic process.


Asunto(s)
Epilepsia/sangre , Epilepsia/diagnóstico , Accidente Cerebrovascular/sangre , Accidente Cerebrovascular/diagnóstico , Anciano , Anciano de 80 o más Años , Biomarcadores/sangre , Estudios de Cohortes , Endostatinas/sangre , Epilepsia/fisiopatología , Femenino , Proteínas del Choque Térmico HSC70/sangre , Humanos , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Estudios Prospectivos , Factores de Riesgo , Subunidad beta de la Proteína de Unión al Calcio S100/sangre , Accidente Cerebrovascular/fisiopatología
9.
Cerebrovasc Dis ; 49(5): 550-555, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33091908

RESUMEN

BACKGROUND: The evolution of the symptomatic intracranial occlusion during transfers from primary stroke centers (PSCs) to comprehensive stroke centers (CSCs) for endovascular treatment (EVT) is not widely known. Our aim was to identify factors related to partial or complete recanalization (REC) at CSC arrival in patients with a documented large vessel occlusion (LVO) in PSC transferred for EVT evaluation to better define the workflow at CSC of this group of patients. METHODS: We conducted an observational, multicenter study from a prospective, government-mandated, population-based registry of stroke patients with documented LVO at PSC transferred to CSC for EVT from January 2017 to June 2019. The primary end point was defined as partial or complete REC that precluded EVT at CSC arrival (REC). We evaluated the association between baseline, treatment variables and time intervals with the presence of REC. RESULTS: From 589 patients, the rate of REC at CSC was 10.5% in all LVO patients transferred from PSC to CSC for EVT evaluation. On univariate analysis, lower PSC-NIHSS (median 12vs.16, p = 0.001), tPA treatment at PSC (13.7 vs. 5.0%; p = 0.001), presence of M2 occlusion on PSC (16.8 vs. 9%; p = 0.023), and clinical improvement at CSC arrival (21.7 vs. 9.6% p = 0.001) were associated with REC at CSC. On multivariate analysis, clinical improvement at CSC arrival (p < 0.001, OR: 5.96 95% CI: 2.5-13.9) and PSC tPA treatment predicted REC (p = 0.003, OR: 4.65, 95% CI: 1.73-12.4). CONCLUSION: REC at CSC arrival occurs exceptionally in patients with a documented LVO on PSC. Repeating a second vascular study before EVT would not be necessary in most patients. Despite its modest effect, tPA treatment at PSC was an independent predictor of REC.


Asunto(s)
Isquemia Encefálica/terapia , Procedimientos Endovasculares , Fibrinolíticos/administración & dosificación , Transferencia de Pacientes , Reperfusión , Accidente Cerebrovascular/terapia , Terapia Trombolítica , Activador de Tejido Plasminógeno/administración & dosificación , Anciano , Anciano de 80 o más Años , Isquemia Encefálica/diagnóstico , Isquemia Encefálica/fisiopatología , Procedimientos Endovasculares/efectos adversos , Femenino , Fibrinolíticos/efectos adversos , Humanos , Masculino , Persona de Mediana Edad , Sistema de Registros , Reperfusión/efectos adversos , Estudios Retrospectivos , España , Accidente Cerebrovascular/diagnóstico , Accidente Cerebrovascular/fisiopatología , Terapia Trombolítica/efectos adversos , Activador de Tejido Plasminógeno/efectos adversos , Resultado del Tratamiento , Flujo de Trabajo
10.
Epilepsy Behav ; 104(Pt B): 106549, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-31677998

RESUMEN

INTRODUCTION: Blood biomarkers have not been widely studied in stroke-related seizures. In this study, we aimed to describe clinical factors and biomarkers present during acute stroke and to analyze their association with early-onset seizures. METHODS: We retrospectively evaluated a panel of 14 blood biomarkers in 1115 patients with ischemic and hemorrhagic stroke. Biomarkers were normalized and standardized using Z scores. We also recorded stroke and epilepsy-related variables, including stroke severity (National Institute of Health Stroke Scale [NIHSS] scores), type, and causes, time from onset of stroke to occurrence of early seizures, and type of seizure. Adjusted logistic regression models were built to identify clinical variables and biomarkers independently associated with early seizures. RESULTS: Mean ±â€¯standard deviation (SD) age was 72.3 ±â€¯13.2 years, and 56.8% of the patients were men. Thirty-eight patients (3.9%) developed early seizures with a median time to onset of 1 day (interquartile range (IQR), 0-4). A higher NIHSS score (odds ratio [OR] = 1.046; 95% confidence interval (CI): 1.001-1.094; p = 0.044) and hemorrhagic stroke (OR = 2.133; 95% CI: 1.010-4.504; p = 0.047) were independently associated with a greater risk of early seizures. Independent blood biomarkers predictive of early seizures were lower levels of tumor necrosis factor receptor 1 (TNF-R1) (<0.013) (p = 0.006; OR = 3.334; 95% CI: 1.414-7.864) and higher levels of neural cell adhesion molecule (NCAM) (>0.326) (p = 0.009; OR = 2.625; 95% CI: 1.271-5.420). The predictive power of the regression model was greater when clinical variables were combined with blood biomarkers (73.5%; 95% CI: 65.1%-81.9%) than when used alone (64%; 95% CI: 55%-72.9%). CONCLUSION: Higher NCAM and lower TNF-R1 levels may help predict the occurrence of early seizures. The combined use of these biomarkers and clinical variables could be useful for identifying patients at risk of seizures. This article is part of the Special Issue "Seizures & Stroke".


Asunto(s)
Convulsiones/sangre , Convulsiones/etiología , Accidente Cerebrovascular/sangre , Accidente Cerebrovascular/complicaciones , Edad de Inicio , Anciano , Anciano de 80 o más Años , Biomarcadores/sangre , Femenino , Humanos , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Estudios Retrospectivos , Factores de Riesgo , Convulsiones/diagnóstico , Accidente Cerebrovascular/diagnóstico
11.
BMC Biol ; 17(1): 88, 2019 11 11.
Artículo en Inglés | MEDLINE | ID: mdl-31711484

RESUMEN

BACKGROUND: Aspergillus spp. comprises a very diverse group of lower eukaryotes with a high relevance for industrial applications and clinical implications. These multinucleate species are often cultured for many generations in the laboratory, which can unknowingly propagate hidden genetic mutations. To assess the likelihood of such events, we studied the genome stability of aspergilli by using a combination of mutation accumulation (MA) lines and whole genome sequencing. RESULTS: We sequenced the whole genomes of 30 asexual and 10 sexual MA lines of three Aspergillus species (A. flavus, A. fumigatus and A. nidulans) and estimated that each MA line accumulated mutations for over 4000 mitoses during asexual cycles. We estimated mutation rates of 4.2 × 10-11 (A. flavus), 1.1 × 10-11 (A. fumigatus) and 4.1 × 10-11 (A. nidulans) per site per mitosis, suggesting that the genomes are very robust. Unexpectedly, we found a very high rate of GC → TA transversions only in A. flavus. In parallel, 30 asexual lines of the non-homologous end-joining (NHEJ) mutants of the three species were also allowed to accumulate mutations for the same number of mitoses. Sequencing of these NHEJ MA lines gave an estimated mutation rate of 5.1 × 10-11 (A. flavus), 2.2 × 10-11 (A. fumigatus) and 4.5 × 10-11 (A. nidulans) per base per mitosis, which is slightly higher than in the wild-type strains and some ~ 5-6 times lower than in the yeasts. Additionally, in A. nidulans, we found a NHEJ-dependent interference of the sexual cycle that is independent of the accumulation of mutations. CONCLUSIONS: We present for the first time direct counts of the mutation rate of filamentous fungal species and find that Aspergillus genomes are very robust. Deletion of the NHEJ machinery results in a slight increase in the mutation rate, but at a rate we suggest is still safe to use for biotechnology purposes. Unexpectedly, we found GC→TA transversions predominated only in the species A. flavus, which could be generated by the hepatocarcinogen secondary metabolite aflatoxin. Lastly, a strong effect of the NHEJ mutation in self-crossing was observed and an increase in the mutations of the asexual lines was quantified.


Asunto(s)
Aspergillus flavus/genética , Genoma Fúngico , Mutación , Mapeo Cromosómico
12.
Stroke ; 48(2): 375-378, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-28062859

RESUMEN

BACKGROUND AND PURPOSE: Whether intravenous thrombolysis adds a further benefit when given before endovascular thrombectomy (EVT) is unknown. Furthermore, intravenous thrombolysis delays time to groin puncture, mainly among drip and ship patients. METHODS: Using region-wide registry data, we selected cases that received direct EVT or combined intravenous thrombolysis+EVT for anterior circulation strokes between January 2011 and October 2015. Treatment effect was estimated by stratification on a propensity score. The average odds ratios for the association of treatment with good outcome and death at 3 months and symptomatic bleedings at 24 hours were calculated with the Mantel-Haenszel test statistic. RESULTS: We included 599 direct EVT patients and 567 patients with combined treatment. Stratification through propensity score achieved balance of baseline characteristics across treatment groups. There was no association between treatment modality and good outcome (odds ratio, 0.97; 95% confidence interval, 0.74-1.27), death (odds ratio, 1.07; 95% confidence interval, 0.74-1.54), or symptomatic bleedings (odds ratio, 0.56; 95% confidence interval, 0.25-1.27). CONCLUSIONS: This observational study suggests that outcomes after direct EVT or combined intravenous thrombolysis+EVT are not different. If confirmed by a randomized controlled trial, it may have a significant impact on organization of stroke systems of care.


Asunto(s)
Procedimientos Endovasculares/tendencias , Accidente Cerebrovascular/diagnóstico , Accidente Cerebrovascular/tratamiento farmacológico , Trombectomía/tendencias , Administración Intravenosa , Anciano , Anciano de 80 o más Años , Terapia Combinada , Procedimientos Endovasculares/mortalidad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Sistema de Registros , Accidente Cerebrovascular/mortalidad , Trombectomía/mortalidad , Terapia Trombolítica/mortalidad , Terapia Trombolítica/tendencias , Resultado del Tratamiento
13.
Stroke ; 48(5): 1147-1153, 2017 05.
Artículo en Inglés | MEDLINE | ID: mdl-28411264

RESUMEN

BACKGROUND AND PURPOSE: Vascular recurrence occurs in 11% of patients during the first year after ischemic stroke (IS) or transient ischemic attack. Clinical scores do not predict the whole vascular recurrence risk; therefore, we aimed to find genetic variants associated with recurrence that might improve the clinical predictive models in IS. METHODS: We analyzed 256 polymorphisms from 115 candidate genes in 3 patient cohorts comprising 4482 IS or transient ischemic attack patients. The discovery cohort was prospectively recruited and included 1494 patients, 6.2% of them developed a new IS during the first year of follow-up. Replication analysis was performed in 2988 patients using SNPlex or HumanOmni1-Quad technology. We generated a predictive model using Cox regression (GRECOS score [Genotyping Reurrence Risk of Stroke]) and generated risk groups using a classification tree method. RESULTS: The analyses revealed that rs1800801 in the MGP gene (hazard ratio, 1.33; P=9×10-03), a gene related to artery calcification, was associated with new IS during the first year of follow-up. This polymorphism was replicated in a Spanish cohort (n=1.305); however, it was not significantly associated in a North American cohort (n=1.683). The GRECOS score predicted new IS (P=3.2×10-09) and could classify patients, from low risk of stroke recurrence (1.9%) to high risk (12.6%). Moreover, the addition of genetic risk factors to the GRECOS score improves the prediction compared with previous Stroke Prognosis Instrument-II score (P=0.03). CONCLUSIONS: The use of genetics could be useful to estimate vascular recurrence risk after IS. Genetic variability in the MGP gene was associated with vascular recurrence in the Spanish population.


Asunto(s)
Isquemia Encefálica/genética , Enfermedades Cardiovasculares/genética , Accidente Cerebrovascular/genética , Anciano , Isquemia Encefálica/diagnóstico , Enfermedades Cardiovasculares/diagnóstico , Estudios de Cohortes , Femenino , Genotipo , Humanos , Ataque Isquémico Transitorio/diagnóstico , Ataque Isquémico Transitorio/genética , Masculino , América del Norte , Polimorfismo de Nucleótido Simple , Pronóstico , Recurrencia , Riesgo , Escocia , España , Accidente Cerebrovascular/diagnóstico
14.
Mol Microbiol ; 99(1): 15-33, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26353949

RESUMEN

Nitric oxide (NO) is a signalling molecule involved in many biological processes in bacteria, plants and mammals. However, little is known about the role and biosynthesis of NO in fungi. Here we show that NO production is increased at the early stages of the transition from vegetative growth to development in Aspergillus nidulans. Full NO production requires a functional nitrate reductase (NR) gene (niaD) that is upregulated upon induction of conidiation, even under N-repressing conditions in the presence of ammonium. At this stage, NO homeostasis is achieved by balancing biosynthesis (NR) and catabolism (flavohaemoglobins). niaD and flavohaemoglobin fhbA are transiently upregulated upon induction of conidiation, and both regulators AreA and NirA are necessary for this transcriptional response. The second flavohaemoglobin gene fhbB shows a different expression profile being moderately expressed during the early stages of the transition phase from vegetative growth to conidiation, but it is strongly induced 24 h later. NO levels influence the balance between conidiation and sexual reproduction because artificial strong elevation of NO levels reduced conidiation and induced the formation of cleistothecia. The nitrate-independent and nitrogen metabolite repression-insensitive transcriptional upregulation of niaD during conidiation suggests a novel role for NR in linking metabolism and development.


Asunto(s)
Aspergillus nidulans/enzimología , Aspergillus nidulans/metabolismo , Regulación Fúngica de la Expresión Génica , Nitrato-Reductasa/metabolismo , Óxido Nítrico/metabolismo , Aspergillus nidulans/genética , Aspergillus nidulans/crecimiento & desarrollo , Esporas Fúngicas/crecimiento & desarrollo , Transcripción Genética
15.
Stroke ; 47(5): 1381-4, 2016 05.
Artículo en Inglés | MEDLINE | ID: mdl-27032445

RESUMEN

BACKGROUND AND PURPOSE: Since demonstration of the benefit of endovascular treatment (EVT) in acute ischemic stroke patients with proximal arterial occlusion, stroke care systems need to be reorganized to deliver EVT in a timely and equitable way. We analyzed differences in the access to EVT by geographical areas in Catalonia, a territory with a highly decentralized stroke model. METHODS: We studied 965 patients treated with EVT from a prospective multicenter population-based registry of stroke patients treated with reperfusion therapies in Catalonia, Spain (SONIIA). Three different areas were defined: (A) health areas primarily covered by Comprehensive Stroke Centers, (B) areas primarily covered by local stroke centers located less than hour away from a Comprehensive Stroke Center, and (C) areas primarily covered by local stroke centers located more than hour away from a Comprehensive Stroke Center. We compared the number of EVT×100 000 inhabitants/year and time from stroke onset to groin puncture between groups. RESULTS: Baseline characteristics were similar between groups. Throughout the study period, there were significant differences in the population rates of EVT across geographical areas. EVT rates by 100 000 in 2015 were 10.5 in A area, 3.7 in B, and 2.7 in C. Time from symptom onset to groin puncture was 82 minutes longer in group B (312 minutes [245-435]) and 120 minutes longer in group C (350 minutes [284-408]) compared with group A (230 minutes [160-407]; P<0.001). CONCLUSIONS: Accessibility to EVT from remote areas is hampered by lower rate and longer time to treatment compared with areas covered directly by Comprehensive Stroke Centers.


Asunto(s)
Atención a la Salud/estadística & datos numéricos , Procedimientos Endovasculares/estadística & datos numéricos , Hospitales Especializados/estadística & datos numéricos , Sistema de Registros/estadística & datos numéricos , Reperfusión/estadística & datos numéricos , Accidente Cerebrovascular/terapia , Terapia Trombolítica/estadística & datos numéricos , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , España
16.
Stroke ; 47(8): 2003-9, 2016 08.
Artículo en Inglés | MEDLINE | ID: mdl-27406103

RESUMEN

BACKGROUND AND PURPOSE: Remote parenchymal hemorrhage (rPH) after intravenous thrombolysis with recombinant tissue-type plasminogen activator may be associated with cerebral amyloid angiopathy, although supportive data are limited. We aimed to investigate risk factors of rPH after intravenous thrombolysis with recombinant tissue-type plasminogen activator. METHODS: This is an observational study of patients with ischemic stroke who were treated with intravenous thrombolysis with recombinant tissue-type plasminogen activator and were included in a multicenter prospective registry. rPH was defined as any extraischemic hemorrhage detected in the follow-up computed tomography. We collected demographic, clinical, laboratory, radiological, and outcome variables. In the subset of patients who underwent a magnetic resonance imaging examination, we evaluated the distribution and burden of cerebral microbleeds, cortical superficial siderosis, leukoaraiosis, and recent silent ischemia in regions anatomically unrelated to the ischemic lesion that caused the initial symptoms. We compared patients with rPH with those without rPH or parenchymal hemorrhage. Independent risk factors for rPH were obtained by multivariable logistic regression analyses. RESULTS: We evaluated 992 patients (mean age, 74.0±12.6 years; 52.9% were men), and 408 (41%) of them underwent a magnetic resonance imaging. Twenty-six patients (2.6%) had a rPH, 8 (0.8%) had both rPH and PH, 58 (5.8%) had PH, and 900 (90.7%) had no bleeding complication. Lobar cerebral microbleeds (odds ratio, 8.0; 95% confidence interval, 2.3-27.2) and recent silent ischemia (odds ratio, 4.8; 95% confidence interval, 1.6-14.1) increased the risk of rPH. CONCLUSIONS: The occurrence of rPH after intravenous thrombolysis with recombinant tissue-type plasminogen activator in patients with ischemic stroke is associated with lobar cerebral microbleeds and multiple ischemic lesions in different regions.


Asunto(s)
Isquemia Encefálica/tratamiento farmacológico , Encéfalo/diagnóstico por imagen , Angiopatía Amiloide Cerebral/diagnóstico por imagen , Hemorragia Cerebral/inducido químicamente , Fibrinolíticos/efectos adversos , Accidente Cerebrovascular/tratamiento farmacológico , Activador de Tejido Plasminógeno/efectos adversos , Anciano , Anciano de 80 o más Años , Isquemia Encefálica/diagnóstico por imagen , Femenino , Fibrinolíticos/uso terapéutico , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Sistema de Registros , Factores de Riesgo , Accidente Cerebrovascular/diagnóstico por imagen , Activador de Tejido Plasminógeno/uso terapéutico
17.
Stroke ; 47(11): 2870-2873, 2016 11.
Artículo en Inglés | MEDLINE | ID: mdl-27758944

RESUMEN

BACKGROUND AND PURPOSE: The STARS trial (Stroke Treatment With Acute Reperfusion and Simvastatin) was conducted to demonstrate the efficacy and safety of simvastatin treatment in acute stroke. METHODS: STARS07 was a multicentre, phase IV, prospective, randomized, double-blind, placebo-controlled trial. Patients with Acute ischemic stroke recruited within 12 hours from symptom onset were randomized to oral simvastatin 40 mg or placebo, once daily for 90 days. Primary outcome was proportion of independent patients (modified Rankin Scale score of ≤2) at 90 days. Safety end points were hemorrhagic transformation, hemorrhagic events, death, infections, and serious adverse events. RESULTS: From April 2009 to March 2014, 104 patients were included. Fifty-five patients received intravenous tissue-type plasminogen activator. No differences were found between treatment arms regarding the primary outcome (adjusted odds ratio, 0.99 [0.35-2.78]; P=0.98). Concerning safety, no significant differences were found in the rate of hemorrhagic transformation of any type, nor symptomatic hemorrhagic transformation. There were no differences in other predefined safety outcomes. In post hoc analyses, for patients receiving tissue-type plasminogen activator, a favorable effect for simvastatin treatment was noted with higher proportion of patients experiencing major neurological recovery (adjusted odds ratio, 4.14 [1.18-14.4]; P=0.02). CONCLUSIONS: Simvastatin plus tissue-type plasminogen activator combination seems safe in acute stroke, with low rates of bleeding complications. Because of the low recruitment, the STARS trial was underpowered to detect differences in simvastatin efficacy. CLINICAL TRIAL REGISTRATION: URL: http://www.clinicaltrials.gov. Unique identifier: NCT01073007.


Asunto(s)
Isquemia Encefálica/tratamiento farmacológico , Fibrinolíticos/farmacología , Inhibidores de Hidroximetilglutaril-CoA Reductasas/farmacología , Evaluación de Resultado en la Atención de Salud , Simvastatina/farmacología , Accidente Cerebrovascular/tratamiento farmacológico , Activador de Tejido Plasminógeno/farmacología , Anciano , Anciano de 80 o más Años , Método Doble Ciego , Quimioterapia Combinada , Femenino , Fibrinolíticos/administración & dosificación , Fibrinolíticos/efectos adversos , Humanos , Inhibidores de Hidroximetilglutaril-CoA Reductasas/administración & dosificación , Inhibidores de Hidroximetilglutaril-CoA Reductasas/efectos adversos , Masculino , Persona de Mediana Edad , Simvastatina/administración & dosificación , Simvastatina/efectos adversos , Activador de Tejido Plasminógeno/administración & dosificación , Activador de Tejido Plasminógeno/efectos adversos
18.
Curr Genet ; 62(3): 513-8, 2016 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-26886232

RESUMEN

Nitric oxide (NO) is a remarkable gaseous molecule with multiple and important roles in different organisms, including fungi. However, the study of the biology of NO in fungi has been hindered by the lack of a complete knowledge on the different metabolic routes that allow a proper NO balance, and the regulation of these routes. Fungi have developed NO detoxification mechanisms to combat nitrosative stress, which have been mainly characterized by their connection to pathogenesis or nitrogen metabolism. However, the progress on the studies of NO anabolic routes in fungi has been hampered by efforts to disrupt candidate genes that gave no conclusive data until recently. This review summarizes the different roles of NO in fungal biology and pathogenesis, with an emphasis on the alternatives to explain fungal NO production and the recent findings on the involvement of nitrate reductase in the synthesis of NO and its regulation during fungal development.


Asunto(s)
Hongos/metabolismo , Óxido Nítrico/metabolismo , Hongos/genética , Hongos/patogenicidad , Homeostasis , Interacciones Huésped-Patógeno , Micosis/microbiología , Oxidación-Reducción
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