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1.
Ecol Lett ; 27(8): e14490, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39152685

RESUMEN

Species' traits and interactions are products of evolutionary history. Despite the long-standing hypothesis that closely related species possess similar traits, and thus experience stronger competition, measuring the effect of evolutionary history on the ecology of natural communities remains challenging. We propose a novel framework to test whether phylogeny influences patterns of coexistence and abundance of species assemblages. In our approach, phylogenetic trees are used to parameterize species' interactions, which in turn determine the abundance of species in a given assemblage. We use likelihoods to score models parameterized with a given phylogeny, and contrast them with models built using random trees, allowing us to test whether phylogenetic information helps to predict species' abundances. Our statistical framework reveals that interactions are indeed structured by phylogeny in a large set of experimental plant communities. Our results confirm that evolutionary history can help predict, and potentially manage or conserve, the structure and function of complex ecological communities.


Asunto(s)
Filogenia , Plantas , Modelos Biológicos , Evolución Biológica , Ecosistema , Biota
2.
MAGMA ; 37(3): 449-463, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38613715

RESUMEN

PURPOSE: Use a conference challenge format to compare machine learning-based gamma-aminobutyric acid (GABA)-edited magnetic resonance spectroscopy (MRS) reconstruction models using one-quarter of the transients typically acquired during a complete scan. METHODS: There were three tracks: Track 1: simulated data, Track 2: identical acquisition parameters with in vivo data, and Track 3: different acquisition parameters with in vivo data. The mean squared error, signal-to-noise ratio, linewidth, and a proposed shape score metric were used to quantify model performance. Challenge organizers provided open access to a baseline model, simulated noise-free data, guides for adding synthetic noise, and in vivo data. RESULTS: Three submissions were compared. A covariance matrix convolutional neural network model was most successful for Track 1. A vision transformer model operating on a spectrogram data representation was most successful for Tracks 2 and 3. Deep learning (DL) reconstructions with 80 transients achieved equivalent or better SNR, linewidth and fit error compared to conventional 320 transient reconstructions. However, some DL models optimized linewidth and SNR without actually improving overall spectral quality, indicating a need for more robust metrics. CONCLUSION: DL-based reconstruction pipelines have the promise to reduce the number of transients required for GABA-edited MRS.


Asunto(s)
Aprendizaje Profundo , Espectroscopía de Resonancia Magnética , Relación Señal-Ruido , Ácido gamma-Aminobutírico , Ácido gamma-Aminobutírico/metabolismo , Humanos , Espectroscopía de Resonancia Magnética/métodos , Redes Neurales de la Computación , Algoritmos , Encéfalo/diagnóstico por imagen , Encéfalo/metabolismo , Aprendizaje Automático , Procesamiento de Imagen Asistido por Computador/métodos , Simulación por Computador
3.
J Environ Manage ; 368: 122091, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39116814

RESUMEN

Third-generation biofuels from microalgae are becoming necessary for sustainable energy. In this context, this study explores the hydrothermal liquefaction (HTL) of microalgae biomass grown in wastewater, consisting of 30% Chlorella vulgaris, 69% Tetradesmus obliquus, and 1% cyanobacteria Limnothrix planctonica, and the subsequent upgrading of the produced bio-oil. The novelty of the work lies in integrating microalgae cultivation in wastewater with HTL in a biorefinery approach, enhanced using a catalyst to upgrade the bio-oil. Different temperatures (300, 325, and 350 °C) and reaction times (15, 30, and 45 min) were tested. The bio-oil upgrading occurred with a Cobalt-Molybdenum (CoMo) catalyst for 1 h at 375 °C. Post-HTL, although the hydrogen-to-carbon (H/C) ratio decreased from 1.70 to 1.38-1.60, the oxygen-to-carbon (O/C) ratio also decreased from 0.39 to 0.079-0.104, and the higher heating value increased from 20.6 to 36.4-38.3 MJ kg-1. Palmitic acid was the main component in all bio-oil samples. The highest bio-oil yield was at 300 °C for 30 min (23.4%). Upgrading increased long-chain hydrocarbons like heptadecane (5%), indicating biofuel potential, though nitrogenous compounds such as hexadecanenitrile suggest a need for further hydrodenitrogenation. Aqueous phase, solid residues, and gas from HTL can be used for applications such as biomass cultivation, bio-hydrogen, valuable chemicals, and materials like carbon composites and cement additives, promoting a circular economy. The study underscores the potential of microalgae-derived bio-oil as sustainable biofuel, although further refinement is needed to meet current fuel standards.


Asunto(s)
Biocombustibles , Biomasa , Microalgas , Aguas Residuales , Microalgas/crecimiento & desarrollo , Aguas Residuales/química , Catálisis , Chlorella vulgaris/crecimiento & desarrollo , Chlorella vulgaris/metabolismo
4.
Caries Res ; 57(1): 21-31, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36642070

RESUMEN

This study aimed at evaluating the mineral variation induced by polyalkenoate cements in residual dentine after different caries removal methods. Ten extracted sound molars were selected, and five cavities were prepared on the occlusal surface of each specimen. Carious lesions were generated using a microbial protocol, while the caries removal was performed using bur, hand excavator, or two papain-based chemo-mechanical agents. One cavity was left unexcavated in each tooth. Cavities were restored using a zinc polycarboxylate cement (ZPC; n = 25), or a glass ionomer cement (GIC) was used (n = 25). Subsequently, the specimens were stored under simulated pulpal pressure for 45 days. Micro-CT scanning was performed after caries formation, removal, and restoration. Cavity volumes (mm3) and mineral density (MD) changes were calculated. Remineralisation ability was investigated by scanning electron microscopy (SEM) and Fourier-transformed infrared spectroscopy (FTIR). Statistical analysis was performed (5% significance level). Baseline caries, cavity volume, and MD increase after caries removal were similar to all excavation groups (p > 0.05). MD was higher in ZPC compared to GIC (p < 0.05). SEM revealed that the chemo-mechanical techniques produced a smoother dentine surface compared to mechanical methods. FTIR showed silicon-based minerals in GIC-treated dentine, while ZPC-treated presented mineral deposits characterised by amorphous calcium phosphate. In both cases, the presence of carbonates was detected on dentine surfaces. All caries removal techniques performed similarly in terms of carious dentine excavation. ZPC can be used as dentine replacement material after caries removal as it may induce higher MD increase in residual dentine via deposition of calcium phosphates, compared to GIC.


Asunto(s)
Caries Dental , Cementos de Ionómero Vítreo , Humanos , Cementos de Ionómero Vítreo/uso terapéutico , Susceptibilidad a Caries Dentarias , Minerales , Caries Dental/terapia , Caries Dental/patología , Dentina/patología
5.
Lett Appl Microbiol ; 76(9)2023 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-37738442

RESUMEN

Pseudomonas aeruginosa is a Gram-negative bacillus associated with waterborne diseases. The objective of this study was to determine whether particular P. aeruginosa sequence types (STs) were associated with drinking water contamination in Brazil. This was achieved by searching the Pseudomonas PubMLST database, which contains the records for 8358 strains collected between 1938 and 2023. The majority (97.2%) had the complete 7-loci multilocus sequence typing profile and were assigned to 3486 STs. After eBURST (an algorithm used to infer patterns of evolutionary descent among clusters), 1219 groups with single-locus variant and 575 groups with double-locus variant were formed. Brazil was the South American country with the most isolates (n = 219, 58.24%), and the Simpson's index was 0.9392. Of the 219 Brazilian isolates, eight were isolated in water and identified as STs 252, 1417, 1605, 2502, 2620, 3078, and 3312. ST252, 1417, and 3078 have already been isolated from clinical cases worldwide. Furthermore, ST1605 and 2620, after the eBURST, they were grouped in the same clonal complex as STs involved in human infections. In conclusion, P. aeruginosa STs involved in human infections were found in bottled drinking water commercialized in Brazil, revealing that these types of drinking waters can be a vehicle of contamination.


Asunto(s)
Agua Potable , Infecciones por Pseudomonas , Humanos , Tipificación de Secuencias Multilocus , Pseudomonas aeruginosa/genética , Brasil/epidemiología , Genotipo , Infecciones por Pseudomonas/epidemiología
6.
An Acad Bras Cienc ; 95(suppl 1): e20201878, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37585966

RESUMEN

Alpinia zerumbet is a plant popularly used to treat hypertension and anxiety. Studies with Alpinia zerumbet demonstrate antihypertensive and vasodilator effects, among others. The objective of this study was to analyze the effect of essential oil of Alpinia zerumbet (EOAz) on cardiovascular and autonomic function in rats with isoproterenol-induced myocardial infarction. Male Wistar rats (n=32) were equally allocated into four groups: Control, ISO (150mg/kg, subcutaneous), EOAz (100mg/kg by gavage), ISO+EOAz. The rats were evaluated for cardiovascular and, autonomic parameters, electrocardiogram, and infarct size. EOAz was not able to reduce the electrocardiographic variations induced by ISO. Heart rate variability showed a decrease in sympathetic modulation on the heart in the groups treated with EOAz. The cardiopulmonary reflex induced by serotonin invoked a superior blood pressure variation at the 2 µg/kg dose in the EOAz treated groups, while the heart rate variation was significantly higher at the 16 µg/kg dose, when compared to other doses, in all groups, except EOAz+ISO. The sympathetic vagal index was higher in ISO group than in control. EOAz did not reduce the infarct size. We conclude that pretreatment with EOAz does not reverse the hemodynamic and electrocardiographic damage caused by isoproterenol but does reduce sympathetic modulation.


Asunto(s)
Alpinia , Infarto del Miocardio , Aceites Volátiles , Ratas , Animales , Aceites Volátiles/farmacología , Aceites Volátiles/uso terapéutico , Isoproterenol , Ratas Wistar , Hojas de la Planta , Infarto del Miocardio/inducido químicamente , Infarto del Miocardio/tratamiento farmacológico
7.
Int J Environ Health Res ; 33(12): 1430-1442, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-35917483

RESUMEN

To investigate the influence of climate on hospitalizations of sickle cell anemia (SCA) adults and children, we analyzed the health and meteorological parameters from a metropolis (1999-2018). 1462 hospitalizations were coded for SCA patients in crisis (M:F = 715:747) and 1354 hospitalizations for SCA patients without crisis (M:F = 698:656) [age = 22.9 vs 15.2 years and duration of hospitalization (DoH) = 5.7 vs 4.4 days, respectively,]. More hospitalizations were for adults than children in crisis, and for children than adults without crisis. More children and adults were hospitalized in winter andspring than in summer and autumn Hospitalizations correlated positively with humidity (lag -5), maximum pressure (lag -2), mean pressure (lag -2), and thermal amplitude (lag -2), and negatively with maximum temperature (lag -3). DoH positively correlated with minimum temperature (lag -4). Understanding these complex associations would induce attitudinal/behavioral modifications among patients and their caregivers.


Asunto(s)
Anemia de Células Falciformes , Clima , Niño , Adulto , Humanos , Adulto Joven , Estudios Retrospectivos , Brasil/epidemiología , Anemia de Células Falciformes/epidemiología , Hospitalización
8.
J Community Psychol ; 51(1): 137-153, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-35640014

RESUMEN

While research on microaggressions has accumulated in recent decades, doubts have arisen over their impact on individuals. Hence, the purpose of this study was to analyze the relations between microaggressions and psychological well-being, physical health, job outcomes, and positive and negative coping. Potential moderators (i.e., microaggression target, publication year, publication status, sample occupation, and inclusion of nonstigmatized group members) were also examined. A meta-analytic approach was chosen to summarize the findings in the microaggression literature. Several search terms and databases were used to identify articles for inclusion. After review, a total of 141 articles with 154 samples contributed effect sizes to our analyses. The results showed that microaggressions were negatively related to psychological well-being and physical health and positively related to coping. The pattern of results was generally the same regardless of the microaggression target, the year the study was conducted, the publication status of the paper, the occupation of the sample, and whether the sample included nonstigmatized groups members or not. This meta-analysis demonstrates the stable, harmful effects associated with experiencing microaggressions. Specifically, microaggressions predicted negative outcomes across individuals and contexts. Thus, actions should be taken to decrease their prevalence within educational and occupational settings.


Asunto(s)
Bienestar Psicológico , Humanos , Microagresión
9.
Nutr Cancer ; 74(6): 2142-2151, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-34519606

RESUMEN

Casein kinase 2 (CK2) plays a critical role in the proliferation and apoptosis of cancer cells. Resveratrol is a bioactive compound with anticancer and anti-inflammatory effects. This study investigated the pro-oxidant cytotoxic effects of resveratrol in association with the inhibition of CK2 activity on human breast carcinoma cells MCF-7. We showed that resveratrol and TBB, an inhibitor of CK2, decreased cell viability in a concentration dependent manner with an IC50 value of 238 µM and 106 µM after 24 h, of treatment, respectively. Resveratrol and TBB decreased CK2 activity by 1.6 and 1.4-fold, respectively, and both significantly decreased mitochondrial membrane potential. However, only resveratrol increased reactive oxygen species (ROS) levels by 1.7-fold as opposed to TBB, which did not affect ROS levels. Indeed, incubating MCF-7 cells with the antioxidant polyethylene glycol-catalase (PEG-CAT) preserved cell viability from the cytotoxic effects of resveratrol, but not from TBB toxicity. This effect seemed to be related to PEG-CAT ability to prevent CK2 inhibition induced by resveratrol incubation. In conclusion, this study demonstrated that the cytotoxic effect of resveratrol on MCF-7 cells might be associated with its pro-oxidant action, which inhibited CK2 activity, affecting cell viability and mitochondrial function.


Asunto(s)
Antineoplásicos , Neoplasias de la Mama , Antineoplásicos/farmacología , Apoptosis , Neoplasias de la Mama/tratamiento farmacológico , Quinasa de la Caseína II/metabolismo , Quinasa de la Caseína II/farmacología , Femenino , Humanos , Células MCF-7 , Especies Reactivas de Oxígeno/metabolismo , Resveratrol/farmacología
10.
Mol Cell Neurosci ; 116: 103666, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34464708

RESUMEN

Anxiety is an emotional state that affects the quality of human life. Several neurotransmitters are involved in the regulation of anxiety, including glutamate. The major actions of glutamate are mediated by N-methyl-d-aspartate receptors (NMDARs) and α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptors (AMPARs). The present study performed a behavioral and neurochemical analysis of Carioca High-conditioned Freezing (CHF) and Carioca Low-conditioned Freezing (CLF) rats compared with control rats. We evaluated thermal nociception, anxiety-like behavior, depressive-like behavior, spatial memory, habituation memory, and the content and localization of different glutamatergic receptor subunits and postsynaptic density-95 (PSD-95), a postsynaptic protein. The CHF group exhibited an anxious-like phenotype, impairments in habituation and spatial memory, and a depressive-like phenotype compared with the control group. In the ventral hippocampus, an increase in the PSD-95, GluN1 and GluA1 subunits and a decrease in the GluN2A subunit of glutamatergic receptors. The CLF group exhibited a less anxious-like phenotype, hyperlocomotion and habituation impairments. Also, CLF animals, presented, in the ventral hippocampus, an increase in the PSD-95, GluN1 and GluA2 subunits and a decrease in the GluN2B subunit. These results suggest that the differential composition of NMDAR and AMPAR subunits may be related to the modulation of different phenotypes in CHF and CLF rats, which may help identify new targets for therapeutic interventions for anxiety disorders and other comorbidities.


Asunto(s)
Hipocampo , Receptores de N-Metil-D-Aspartato , Animales , Ansiedad , Ácido Glutámico , Hipocampo/metabolismo , Ratas , Receptores de N-Metil-D-Aspartato/genética , Receptores de N-Metil-D-Aspartato/metabolismo , Memoria Espacial , Ácido alfa-Amino-3-hidroxi-5-metil-4-isoxazol Propiónico
11.
Am J Perinatol ; 2022 Jun 23.
Artículo en Inglés | MEDLINE | ID: mdl-35378547

RESUMEN

OBJECTIVE: The risk of intraventricular hemorrhage (IVH) and periventricular leukomalacia is associated with low birth weight and gestational age. Caesarean section (CS) may reduce the risk of IVH, although it has been a matter of debate. The aim of this study was to evaluate the influence of the mode of delivery (MOD) on the development of IVH and cystic periventricular leukomalacia (cPVL). STUDY DESIGN: We analyzed an initial cohort of 11,023 very low birth weight (VLBW) infants born between January 2010 and December 2019. Infants with major malformations and gestational age <23 weeks and ≥32 weeks were excluded. A final cohort of 8,251 newborns was analyzed. Data was collected from Portuguese National very low birth weight registry. Cases were classified as vaginal delivery (VD) or CS. Outcome was assessed in univariate and logistic regression analyses. RESULTS: The median gestational age was 29 weeks (IQR 3.3) and the median weight was 1,100 g (IQR 555). The prevalence of IVH was significantly higher in the VD group versus the CS group, across all grading levels:1,144 newborns had grade I IVH (16% VD vs. 14% CS, p <0.01), 706 had grade II IVH (12% VD vs. 7.6% CS, p <0.01), and 777 had grade III IVH (14% VD vs. 7.9% CS, p <0.01). Post-hemorrhagic ventricular dilatation occurred in 457 newborns (8.3% VD vs. 4.6% CS, p <0.01) and 456 newborns had periventricular hemorrhagic infarction (8.4% VD vs. 4.5% CS, p <0.01). There was no association between MOD and cPVL. After applying a logistic regression analysis, including known risk factors for IVH and cPVL, VD was independently associated with an increased risk of IVH (odds ratio [OR] 1.600[1.423-1.799], p <0.001) and its complications (OR 1.440[1.195-1.735], p <0.001). MOD was not associated with an increased risk of cPVL. CONCLUSION: Our study suggests that CS is associated with a reduced risk of IVH and its complications in preterm VLBW infants < 32 weeks of gestational age. A CS should be considered in this group of infants to prevent the development of IVH and its complications. KEY POINTS: · IVH and cPVL are risk factors for neurological disabilities.. · CS may decrease the risk of IVH in preterms <32 weeks GA.. · There is no association between the MOD and cPVL..

12.
Sex Transm Dis ; 48(3): e48-e50, 2021 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-32976354

RESUMEN

ABSTRACT: A 23-year-old man presented with cough and progressive shortness of breath. Echocardiogram showed a biscupid aortic valve with a large vegetation causing severe regurgitation. Blood cultures were positive for Neisseria gonorrhoeae sensitive to cefotaxime and penicillin. Despite direct antibiotherapy, the patient required cardiac surgery with aortic valve replacement.


Asunto(s)
Insuficiencia de la Válvula Aórtica , Endocarditis Bacteriana , Endocarditis , Gonorrea , Adulto , Válvula Aórtica/diagnóstico por imagen , Válvula Aórtica/cirugía , Insuficiencia de la Válvula Aórtica/diagnóstico por imagen , Insuficiencia de la Válvula Aórtica/cirugía , Endocarditis Bacteriana/complicaciones , Endocarditis Bacteriana/tratamiento farmacológico , Gonorrea/complicaciones , Gonorrea/diagnóstico , Gonorrea/tratamiento farmacológico , Humanos , Masculino , Adulto Joven
13.
Syst Biol ; 68(1): 131-144, 2019 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-29939352

RESUMEN

Phylogenetic trees are representations of evolutionary relationships among species and contain signatures of the processes responsible for the speciation events they display. Inferring processes from tree properties, however, is challenging. To address this problem, we analyzed a spatially-explicit model of speciation where genome size and mating range can be controlled. We simulated parapatric and sympatric (narrow and wide mating range, respectively) radiations and constructed their phylogenetic trees, computing structural properties such as tree balance and speed of diversification. We showed that parapatric and sympatric speciation are well separated by these structural tree properties. Balanced trees with constant rates of diversification only originate in sympatry and genome size affected both the balance and the speed of diversification of the simulated trees. Comparison with empirical data showed that most of the evolutionary radiations considered to have developed in parapatry or sympatry are in good agreement with model predictions. Even though additional forces other than spatial restriction of gene flow, genome size, and genetic incompatibilities, do play a role in the evolution of species formation, the microevolutionary processes modeled here capture signatures of the diversification pattern of evolutionary radiations, regarding the symmetry and speed of diversification of lineages.


Asunto(s)
Evolución Molecular , Modelos Biológicos , Filogenia , Simulación por Computador , Flujo Génico , Especiación Genética , Tamaño del Genoma
14.
Am Nat ; 194(2): 217-229, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-31318284

RESUMEN

The spatial distribution of populations can influence the evolutionary outcome of species interactions. The variation in direction and strength of selection across local communities creates geographic selection mosaics that, when combined with gene flow and genomic processes such as genome duplication or hybridization, can fuel ongoing coevolution. A fundamental problem to solve is how coevolution proceeds when many populations that vary in their ecological outcomes are connected across large landscapes. Here we use a lattice model to explore this problem. Our results show that the complex interrelationships among the elements of the geographic mosaic of coevolution can lead to the formation of clusters of populations with similar phenotypes that are larger than expected by local selection. Our results indicate that neither the spatial distribution of phenotypes nor the spatial differences in magnitude and direction of selection alone dictate coevolutionary dynamics: the geographic mosaic of coevolution affects formation of phenotypic clusters, which in turn affect the spatial and temporal dynamics of coevolution. Because the formation of large phenotypic clusters depends on gene flow, we predict that current habitat fragmentation will change the outcomes of geographic mosaics, coupling spatial patterns in selection and phenotypes.


Asunto(s)
Coevolución Biológica , Flujo Génico , Adaptación Biológica/genética , Distribución Animal , Evolución Biológica , Modelos Teóricos , Fenotipo , Dispersión de las Plantas , Selección Genética
16.
Neuroimmunomodulation ; 25(2): 96-102, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30110698

RESUMEN

OBJECTIVE: Interleukin 4 (IL-4) is an anti-inflammatory cytokine related to different aspects of central nervous system development such as survival, proliferation, and differentiation, among others. Our goals were to investigate the effect of intravitreous treatment with IL-4 on the activation of downstream signaling pathways in the retina and the distribution of retinal axons within the superior colliculus (SC). MATERIAL AND METHODS: Lister hooded rats were submitted to an intravitreous injection of either IL-4 (5 U/µL) or PBS (vehicle) at postnatal day 10 (PND10). At PND11 or PND14, retinas were processed for Western blot or immunohistochemistry. At PND13, a group of animals received an intraocular injection of an anterograde tracer in the left (untreated) eye in order to label the uncrossed retinotectal axons. RESULTS: Our data revealed that intravitreous treatment with IL-4 at PND10 leads to a decrease in GFAP content and a sustained increase in the phosphorylation of STAT6 and ERK levels in the retina. IL-4 also increases retinal axonal arbors within the SC, compared to control groups. CONCLUSIONS: These data suggest that a single in vivo treatment with IL-4 during the early stages of development modulates signaling pathways in the retina, resulting in altered binocular subcortical visual connectivity.


Asunto(s)
Interleucina-4/administración & dosificación , Sistema de Señalización de MAP Quinasas/fisiología , Red Nerviosa/metabolismo , Retina/metabolismo , Factor de Transcripción STAT6/metabolismo , Vías Visuales/metabolismo , Animales , Inyecciones Intravítreas , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Red Nerviosa/efectos de los fármacos , Fosforilación/efectos de los fármacos , Fosforilación/fisiología , Ratas , Retina/efectos de los fármacos , Roedores , Vías Visuales/efectos de los fármacos
17.
J Neuroinflammation ; 14(1): 162, 2017 08 18.
Artículo en Inglés | MEDLINE | ID: mdl-28821276

RESUMEN

BACKGROUND: Multiple sclerosis (MS) is an inflammatory demyelinating disease classically associated with axonal damage and loss; more recently, however, synaptic changes have been recognized as additional contributing factors. An anatomical area commonly affected in MS is the visual pathway; yet, changes other than those associated with inflammatory demyelination of the optic nerve, i.e., optic neuritis, have not been described in detail. METHODS: Adult mice were subjected to a diet containing cuprizone to mimic certain aspects of inflammatory demyelination as seen in MS. Demyelination and inflammation were assessed by real-time polymerase chain reaction and immunohistochemistry. Synaptic changes associated with inflammatory demyelination in the dorsal lateral geniculate nucleus (dLGN) were determined by immunohistochemistry, Western blot analysis, and electrophysiological field potential recordings. RESULTS: In the cuprizone model, demyelination was observed in retinorecipient regions of the subcortical visual system, in particular the dLGN, where it was found accompanied by microglia activation and astrogliosis. In contrast, anterior parts of the pathway, i.e., the optic nerve and tract, appeared largely unaffected. Under the inflammatory demyelinating conditions, as seen in the dLGN of cuprizone-treated mice, there was an overall decrease in excitatory synaptic inputs from retinal ganglion cells. At the same time, the number of synaptic complexes arising from gamma-aminobutyric acid (GABA)-generating inhibitory neurons was found increased, as were the synapses that contain the N-methyl-D-aspartate receptor (NMDAR) subunit GluN2B and converge onto inhibitory neurons. These synaptic changes were functionally found associated with a shift toward an overall increase in network inhibition. CONCLUSIONS: Using the cuprizone model of inflammatory demyelination, our data reveal a novel form of synaptic (mal)adaption in the CNS that is characterized by a shift of the excitation/inhibition balance toward inhibitory network activity associated with an increase in GABAergic inhibitory synapses and a possible increase in excitatory input onto inhibitory interneurons. In addition, our data recognize the cuprizone model as a suitable tool in which to assess the effects of inflammatory demyelination on subcortical retinorecipient regions of the visual system, such as the dLGN, in the absence of overt optic neuritis.


Asunto(s)
Cuprizona/toxicidad , Enfermedades Desmielinizantes/inducido químicamente , Enfermedades Desmielinizantes/patología , Cuerpos Geniculados/patología , Vías Visuales/patología , Animales , Quelantes/toxicidad , Cuerpo Calloso/efectos de los fármacos , Cuerpo Calloso/patología , Cuerpos Geniculados/efectos de los fármacos , Masculino , Ratones , Ratones Endogámicos C57BL , Vías Visuales/efectos de los fármacos
18.
Bioprocess Biosyst Eng ; 40(12): 1839-1850, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28916959

RESUMEN

This study aims to evaluate membrane bioreactor (MBR) performance in a pilot scale to treat petroleum refinery effluent, and has been primarily focused on (1) investigation of dynamics of organic matter removal; (2) characterization of membrane fouling under real hazardous events; (3) evaluation of the effect of fouling on membrane lifetime; and (4) estimate the membrane lifetime. The results have shown that the MBR was able to effectively reduce COD, NH3-N, turbidity, color, phenol and toxicity, and bring them to the levels required to meet disposal and non-potable water reuse standards. The FTIR results showed that organic matter was removed by biological oxidation and/or retained by adsorption in the biological sludge, or retention in the UF membrane, and that SMP was produced during the treatment. In terms of membrane permeability, the results showed that soluble fraction of mixed liquor contributed significantly to membrane fouling. And finally, considering the concept of lifetime based on permeability decline, a membrane lifetime of 7 years is expected.


Asunto(s)
Reactores Biológicos , Residuos Industriales , Membranas Artificiales , Compuestos Orgánicos/aislamiento & purificación , Petróleo/análisis , Contaminantes Químicos del Agua/aislamiento & purificación , Espectroscopía Infrarroja por Transformada de Fourier
20.
Neuroimmunomodulation ; 23(2): 81-7, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27031648

RESUMEN

OBJECTIVE: The development of retinotectal pathways form precise topographical maps is usually completed by the third postnatal week. Cytokines participate in the development and plasticity of the nervous system. We have previously shown that in vivo treatment with interleukin 2 disrupts the retinocollicular topographical order in early stages of development. Therefore, we decided to study the effect of a single intravitreous injection of IL-6 upon retinotectal circuitry in neonates and juvenile rats. MATERIALS AND METHODS: Lister Hooded rats received an intravitreous injection of IL-6 (50 ng/ml) or vehicle (PBS) at either postnatal day (PND)10 or PND30 and the ipsilateral retinotectal pathway was evaluated 4 or 8 days later, respectively. RESULTS: Our data showed that, at different stages of development, a single IL-6 intravitreous treatment did not produce an inflammatory response and increased retinal axon innervation throughout the visual layers of the superior colliculus. CONCLUSIONS: Taken together, our data provide the first evidence that a single intravitreous injection with IL-6 leads to sprouting in the subcortical visual connections and suggest that small changes in IL-6 levels might be sufficient to impair the correct neuronal circuitry fine-tuning during brain development.


Asunto(s)
Interleucina-6/administración & dosificación , Retina/crecimiento & desarrollo , Colículos Superiores/crecimiento & desarrollo , Vías Visuales/crecimiento & desarrollo , Animales , Animales Recién Nacidos , Inyecciones Intravítreas , Plasticidad Neuronal/efectos de los fármacos , Plasticidad Neuronal/fisiología , Ratas , Retina/citología , Retina/efectos de los fármacos , Colículos Superiores/citología , Colículos Superiores/efectos de los fármacos , Vías Visuales/citología , Vías Visuales/efectos de los fármacos
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