Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 188
Filtrar
Más filtros

Intervalo de año de publicación
1.
Cytometry A ; 105(6): 446-457, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38624015

RESUMEN

The COVID-19 pandemic caused by the SARS-CoV-2 virus has highlighted the need for serological assays that can accurately evaluate the neutralizing efficiency of antibodies produced during infection or induced by vaccines. However, conventional assays often require the manipulation of live viruses on a level-three biosafety (BSL3) facility, which presents practical and safety challenges. Here, we present a novel, alternative assay that measures neutralizing antibodies (NAbs) against SARS-CoV-2 in plasma using flow cytometry. This assay is based on antibody binding to the S protein and has demonstrated precision in both intra- and inter-assay measurements at a dilution of 1:50. The cut-off was determined using Receiver Operating Characteristic (ROC) analysis and the value of 36.01% has shown high sensitivity and specificity in distinguishing between pre-pandemic sera, COVID-19 patients, and vaccinated individuals. The efficiency significantly correlates with the gold standard test, PRNT. Our new assay offers a safe and efficient alternative to conventional assays for evaluating NAbs against SARS-CoV-2.


Asunto(s)
Anticuerpos Neutralizantes , Anticuerpos Antivirales , COVID-19 , Citometría de Flujo , SARS-CoV-2 , Humanos , Citometría de Flujo/métodos , SARS-CoV-2/inmunología , Anticuerpos Neutralizantes/inmunología , Anticuerpos Neutralizantes/sangre , COVID-19/inmunología , COVID-19/diagnóstico , COVID-19/virología , Anticuerpos Antivirales/inmunología , Anticuerpos Antivirales/sangre , Glicoproteína de la Espiga del Coronavirus/inmunología , Pruebas de Neutralización/métodos , Prueba Serológica para COVID-19/métodos , Sensibilidad y Especificidad , Masculino , Femenino
2.
Cell Biochem Funct ; 42(1): e3936, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38269522

RESUMEN

Resistance training (RT) with blood flow restriction (BFR) or high intensity (HI) are effective to increase muscle mass. To understand this effect, techniques known as "omics" are used to identify possible biomarkers. This study analyzed the salivary proteomic profile of healthy individuals trained before and after two RT protocols both designed with eight exercises for upper- and lower-limbs, one performed at low percentage of one-maximum repetition (%1RM) with BFR technique, and other at high %1RM (HI) without BRF technique. Four healthy males between 18 and 28 years participated in the study. Stimulated saliva was collected before (BBFR/BHI) and immediately after (ABFR/AHI) the two RT protocols. All protein-related processing was performed using label-free proteomic. The difference in expression between groups was expressed as p < .05 for downregulated proteins and 1-p > .95 for upregulated proteins. There was difference in salivary flow between ABFR and BBFR (p = .005). For HI, 87 proteins were found after the practice and 119 before. Three hemoglobin isoforms were increased in AHI compared with BHI. In the BFR comparison, 105 proteins were identified after (ABFR) and 70 before (BBFR). Among those increased ABFR, we highlight five hemoglobin isoforms and Deleted in malignant brain tumors 1 protein. Between ABFR and AHI, 17 isoforms of histones, Transaldolase, Transketolase, Glyceraldehyde-3-phosphate dehydrogenase, and Antileukoproteinase were decreased ABFR. For HI, there was an increase in proteins related to oxidative stress and metabolism of the musculoskeletal system, compared with BFR. HI seems to induce higher anabolic signaling to muscle mass increase and antiatherosclerotic effects.


Asunto(s)
Entrenamiento de Fuerza , Masculino , Humanos , Proteómica , Histonas , Hemoglobinas , Isoformas de Proteínas
3.
BMC Oral Health ; 24(1): 173, 2024 Feb 02.
Artículo en Inglés | MEDLINE | ID: mdl-38308326

RESUMEN

BACKGROUND: Since color measurements are relative, the discrepancy among different instruments is alarmingly high. This multicenter study evaluated the effectiveness of instrument calibration and inter-instrument harmonization of different spectrophotometers with the same optical geometry using tooth-colored, translucent dental materials. METHODS: The coordinating center (CC) spectrophotometer was calibrated using the NPL Ceram Series II set. Two sets of 10 specimens, labeled 1 to 10 and I to X (10 mm in diameter and 1 mm thick), were tested at CC and three research sites (RS1, RS2, and RS3) using the same d/8° optical geometry spectrophotometers. Calibration factors were calculated for each material and site to obtain the average calibration factors for sets 1-10, set I-X, and the combination of both. The differences among the non-corrected and corrected reflection values were calculated using CIEDE2000 (DeltaE00) and CIELAB (DeltaEab) color difference formulas and were submitted to ANOVA and Tukey test (α = 0.05). RESULTS: A significant decrease of color differences between non-corrected as compared to corrected measurements was recorded for all CC-RS and RS-RS comparisons. The reduction of DeltaE00 values between non-corrected and corrected for CC-RS1, CC-RS2, and CC-RS3 were 83.1%, 77.2%, and 73.6%, respectively. The corresponding DeltaE00 values for RS1-RS2, RS1-RS3, and RS2-RS3 comparisons, indirectly compared in the experiment, were 84.2%, 82.8%, and 68.5%, respectively. There was a significant reduction of DeltaE00 and DeltaEab color difference for all combined RS pairs and each of three RS pairs, corrected with one of two specimen sets calibration factors separately. CONCLUSIONS: Calibration and harmonization of color measurements in dentistry using tooth-colored, translucent restorative materials significantly decreased measurement discrepancies between the coordinating center and research sites and among pairs of research sites.


Asunto(s)
Materiales Dentales , Odontología , Humanos , Color , Espectrofotometría , Ensayo de Materiales
4.
Photochem Photobiol Sci ; 22(2): 279-302, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36152272

RESUMEN

Toluidine blue O (TBO) is a phenothiazine dye that, due to its photochemical characteristics and high affinity for biomembranes, has been revealed as a new photosensitizer (PS) option for antimicrobial photodynamic therapy (PDT). This points to a possible association with membranous organelles like mitochondrion. Therefore, here we investigated its effects on mitochondrial bioenergetic functions both in the dark and under photostimulation. Two experimental systems were utilized: (a) isolated rat liver mitochondria and (b) isolated perfused rat liver. Our data revealed that, independently of photostimulation, TBO presented affinity for mitochondria. Under photostimulation, TBO increased the protein carbonylation and lipid peroxidation levels (up to 109.40 and 119.87%, respectively) and decreased the reduced glutathione levels (59.72%) in mitochondria. TBO also uncoupled oxidative phosphorylation and photoinactivated the respiratory chain complexes I, II, and IV, as well as the FoF1-ATP synthase complex. Without photostimulation, TBO caused uncoupling of oxidative phosphorylation and loss of inner mitochondrial membrane integrity and inhibited very strongly succinate oxidase activity. TBO's uncoupling effect was clearly seen in intact livers where it stimulated oxygen consumption at concentrations of 20 and 40 µM. Additionally, TBO (40 µM) reduced cellular ATP levels (52.46%) and ATP/ADP (45.98%) and ATP/AMP (74.17%) ratios. Consequently, TBO inhibited gluconeogenesis and ureagenesis whereas it stimulated glycogenolysis and glycolysis. In conclusion, we have revealed for the first time that the efficiency of TBO as a PS may be linked to its ability to photodynamically inhibit oxidative phosphorylation. In contrast, TBO is harmful to mitochondrial energy metabolism even without photostimulation, which may lead to adverse effects when used in PDT.


Asunto(s)
Enfermedad Hepática Inducida por Sustancias y Drogas , Mitocondrias Hepáticas , Ratas , Animales , Mitocondrias Hepáticas/metabolismo , Cloruro de Tolonio/metabolismo , Cloruro de Tolonio/farmacología , Metabolismo Energético , Fármacos Fotosensibilizantes/farmacología , Adenosina Trifosfato/metabolismo , Enfermedad Hepática Inducida por Sustancias y Drogas/metabolismo
5.
Curr Issues Mol Biol ; 45(1): 327-336, 2022 Dec 31.
Artículo en Inglés | MEDLINE | ID: mdl-36661509

RESUMEN

The COVID-19 (Coronavirus Disease 2019), caused by the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2), severely affects mainly individuals with pre-existing comorbidities. Here our aim was to correlate the mTOR (mammalian/mechanistic Target of Rapamycin) and autophagy pathways with the disease severity. Through western blotting and RNA analysis, we found increased mTOR signaling and suppression of genes related to autophagy, lysosome, and vesicle fusion in Vero E6 cells infected with SARS-CoV-2 as well as in transcriptomic data mining of bronchoalveolar epithelial cells from severe COVID-19 patients. Immunofluorescence co-localization assays also indicated that SARS-CoV-2 colocalizes within autophagosomes but not with a lysosomal marker. Our findings indicate that SARS-CoV-2 can benefit from compromised autophagic flux and inhibited exocytosis in individuals with chronic hyperactivation of mTOR signaling.

6.
J Phycol ; 58(4): 502-516, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35727130

RESUMEN

While nostocacean cyanobacteria are ubiquitous and play critical roles in terrestrial ecosystems, their taxonomy and biogeography still entail mysteries. We isolated two Nostoc-like cyanobacteria from biological soil crusts of the Atacama (Chile) and Mojave (USA) Deserts. An initial 16S rRNA gene phylogeny placed both in monophyly with Mojavia pulchra. Here, we describe two new species of the previously monotypic Mojavia using a polyphasic approach including morphology, 16S rRNA phylogenies, secondary structure, and percent similarity of the 16S-23S ITS region. Like M. pulchra, both new species produce compact microcolonies, arthrospore-like akinetes, and monocytes, traits characteristic of the genus. Mojavia aguilerae sp. nov. is morphologically distinct from both other species in producing bluntly conical end cells, abundant enlarged akinetes in multiseriate filaments, and gold-colored cells during senescence. Mojavia dolomitestris sp. nov. exhibited distinctly firm, light-colored, compartmentalized mucilage. M. dolomitestris is somewhat cryptic with M. pulchra, but has more densely packed microcolonies, rarity and later onset of brownish sheath pigmentation, and an origin from soils derived from dolomite. The two new species strengthened the position of Mojavia as a robust genus sister to Nostoc. Although 16S rRNA gene data could not separate the Mojavia species from each other, the three species showed distinct dissimilarities in secondary ITS structure and differed greatly from Nostoc sensu stricto. The high dissimilarities between their 16S-23S ITS regions suggest a long evolutionary history of the three species as separate lineages. Mojavia is an evolutionary and ecologically unique nostocacean genus, and its rarity and restricted habitat point to an urgent need for recognition and protection.


Asunto(s)
Ecosistema , Nostoc , ADN Bacteriano/genética , Nostoc/genética , Filogenia , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN
7.
Mem Inst Oswaldo Cruz ; 117: e210194, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35976280

RESUMEN

BACKGROUND: Zika virus (ZIKV) is an emerging arbovirus associated with foetal malformations and neurological complications. The infection is usually associated with mild symptoms. The comparison between the allelic frequency of polymorphic genes in symptomatic infected individuals in the population can clarify the pathogenic mechanisms of ZIKV. During ZIKV infection, cytokines are produced and natural killer (NK) cells are recruited, whose activation depends on signaling pathways activated by specific receptors, such as killer cell immunoglobulin-like receptors (KIR). These molecules interact with human leukocyte antigen (HLA) class I ligands and are encoded by polymorphic genes. OBJECTIVES: This study aimed to evaluate the frequency of allelic variants of the genes encoding the KIR receptors and their HLA class I ligands in 139 symptomatic ZIKV-patients and 170 controls negative for the virus, and to evaluate the role of these variants for ZIKV susceptibility. METHODS: KIR and HLA class I genes were genotyped using the polymerase chain reaction-sequence specific oligonucleotide (PCR-SSO) technique. FINDINGS: No significant differences in the frequency distribution of KIRs and KIR-HLA in patients compared to controls were observed. MAIN CONCLUSIONS: KIR and its HLA ligands might play a minor role in ZIKV infection in the south and southeast Brazilian individuals.


Asunto(s)
Infección por el Virus Zika , Virus Zika , Brasil , Frecuencia de los Genes/genética , Genotipo , Antígenos de Histocompatibilidad Clase I/inmunología , Humanos , Ligandos , Receptores KIR/genética , Virus Zika/genética , Infección por el Virus Zika/genética
8.
J Dairy Sci ; 105(3): 1889-1899, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-34998541

RESUMEN

We evaluated the performance of Limosilactobacillus mucosae CNPC007 as an autochthonous adjunct culture in the production of goat milk Greek-style yogurt. The techno-functional, physicochemical, and sensory characteristics of the control yogurt (containing only starter culture, CY) and the probiotic yogurt (with the probiotic strain added, PY) were assessed during 28 d of refrigerated storage. Furthermore, we determined the survival of the strain throughout the gastrointestinal tract under simulated conditions. The PY yogurt had a lower extent of proteolysis index and a higher depth of proteolysis index. These results indicate that the proteolytic enzymes of L. mucosae may have a possible action in PY. The PY formulation exhibited viscosity almost 1.5 times as high as CY over the refrigeration period, probably due to higher production of exopolysaccharides by the probiotic strain, which directly interferes with the microstructure, texture, and viscosity of the product. The PY formulation received higher scores for color, flavor, and global acceptance at 1 d of storage and higher texture scores at 28 d. The counts of L. mucosae remained high (>7 log cfu/g and >8.5 log cfu/g) throughout mouth-ileum digestion and storage, respectively, in PY. The autochthonous adjunct culture of L. mucosae CNPC007 can be used for production of a novel potentially probiotic goat yogurt without negatively affecting the general characteristics of the product quality, adding value associated with maintaining its functional potential.


Asunto(s)
Probióticos , Yogur , Animales , Fermentación , Tracto Gastrointestinal , Cabras , Leche/química
9.
Emerg Infect Dis ; 27(6): 1737-1740, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33871331

RESUMEN

We documented 4 cases of severe acute respiratory syndrome coronavirus 2 reinfection by non-variant of concern strains among healthcare workers in Campinas, Brazil. We isolated infectious particles from nasopharyngeal secretions during both infection episodes. Improved and continued protection measures are necessary to mitigate the risk for reinfection among healthcare workers.


Asunto(s)
COVID-19/diagnóstico , Personal de Salud , Reinfección/diagnóstico , Reinfección/virología , SARS-CoV-2/aislamiento & purificación , Esparcimiento de Virus , Adulto , Brasil/epidemiología , COVID-19/epidemiología , Femenino , Humanos , Persona de Mediana Edad , Reinfección/terapia
10.
Brain Behav Immun ; 97: 260-274, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34390806

RESUMEN

Zika virus (ZIKV) has the ability to cross placental and brain barriers, causing congenital malformations in neonates and neurological disorders in adults. However, the pathogenic mechanisms of ZIKV-induced neurological complications in adults and congenital malformations are still not fully understood. Gas6 is a soluble TAM receptor ligand able to promote flavivirus internalization and downregulation of immune responses. Here we demonstrate that there is a correlation between ZIKV neurological complications with higher Gas6 levels and the downregulation of genes associated with anti-viral response, as type I IFN due to Socs1 upregulation. Also, Gas6 gamma-carboxylation is essential for ZIKV invasion and replication in monocytes, the main source of this protein, which was inhibited by warfarin. Conversely, Gas6 facilitates ZIKV replication in adult immunocompetent mice and enabled susceptibility to transplacental infection. Our data indicate that ZIKV promotes the upregulation of its ligand Gas6, which contributes to viral infectivity and drives the development of severe adverse outcomes during ZIKV infection.


Asunto(s)
Enfermedades del Sistema Nervioso , Infección por el Virus Zika , Virus Zika , Animales , Femenino , Humanos , Ratones , Placenta , Embarazo , Replicación Viral , Infección por el Virus Zika/complicaciones
11.
Br J Nutr ; 126(6): 865-876, 2021 09 28.
Artículo en Inglés | MEDLINE | ID: mdl-33256869

RESUMEN

The aim of this study was to evaluate the impact of the Dietary Approaches to Stop Hypertension (DASH) diet on glycaemic control and consumption of processed (PF) and ultraprocessed (UPF) foods in pregnant women with pre-gestational diabetes mellitus (PGDM). This is a randomised, controlled, single-blind clinical trial with forty-nine adult women with PGDM, followed at a public maternity hospital in Rio de Janeiro, Brazil. The control group (CG) received a standard diet consisting of 45-55 % of the total energy intake of carbohydrates, 15-20 % of proteins and 25-30 % of lipids. The DASH group (DG) received an adapted DASH diet, which did not differ from the standard diet in the percentage of macronutrients, but had higher contents of fibre, unsaturated fats and minerals such as Ca, Mg and K; and lower contents of Na and saturated fats than the standard diet. In the analysis by protocol, the DG presented a higher incidence of glycaemic control after 12 weeks of intervention (57·1 v. 8·3 %, P = 0·01, moderate effect size) and a lower mean consumption of UPF (-9·9 %, P = 0·01) compared with the CG. There was no statistically significant difference in fasting and postprandial blood glucose concentrations, or in the consumption of PF between the groups (P > 0·05). The DASH diet may be a strategy for glycaemic control in pregnant women with PGDM, favouring the adoption of a nutritionally adequate diet with lower consumption of UPF. Further studies are needed to investigate the effect of the DASH diet on glycaemic profile, and maternal and perinatal outcomes in women with PGDM.


Asunto(s)
Diabetes Gestacional , Enfoques Dietéticos para Detener la Hipertensión , Control Glucémico , Hipertensión , Adulto , Brasil , Diabetes Gestacional/dietoterapia , Dieta , Femenino , Humanos , Hipertensión/prevención & control , Embarazo , Mujeres Embarazadas , Método Simple Ciego
12.
Bioorg Chem ; 109: 104719, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33636437

RESUMEN

Although the widespread epidemic of Zika virus (ZIKV) and its neurological complications are well-known there are still no approved drugs available to treat this arboviral disease or vaccine to prevent the infection. Flavonoids from Pterogyne nitens have already demonstrated anti-flavivirus activity, although their target is unknown. In this study, we virtually screened an in-house database of 150 natural and semi-synthetic compounds against ZIKV NS2B-NS3 protease (NS2B-NS3p) using docking-based virtual screening, as part of the OpenZika project. As a result, we prioritized three flavonoids from P. nitens, quercetin, rutin and pedalitin, for experimental evaluation. We also used machine learning models, built with Assay Central® software, for predicting the activity and toxicity of these flavonoids. Biophysical and enzymatic assays generally agreed with the in silico predictions, confirming that the flavonoids inhibited ZIKV protease. The most promising hit, pedalitin, inhibited ZIKV NS2B-NS3p with an IC50 of 5 µM. In cell-based assays, pedalitin displayed significant activity at 250 and 500 µM, with slight toxicity in Vero cells. The results presented here demonstrate the potential of pedalitin as a candidate for hit-to-lead (H2L) optimization studies towards the discovery of antiviral drug candidates to treat ZIKV infections.


Asunto(s)
Antivirales/farmacología , Proteínas no Estructurales Virales/antagonistas & inhibidores , Proteínas Virales/antagonistas & inhibidores , Virus Zika/metabolismo , Animales , Antivirales/química , Supervivencia Celular/efectos de los fármacos , Chlorocebus aethiops , Inhibidores Enzimáticos/química , Inhibidores Enzimáticos/farmacología , Flavonas/farmacología , Aprendizaje Automático , Modelos Moleculares , Simulación del Acoplamiento Molecular , Conformación Proteica , Quercetina/farmacología , Rutina/farmacología , Serina Endopeptidasas , Células Vero
13.
J Phycol ; 57(3): 886-902, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-33583028

RESUMEN

Cyanobacteria are crucial ecosystem components in dryland soils. Advances in describing α-level taxonomy are needed to understand what drives their abundance and distribution. We describe Trichotorquatus gen. nov. (Oculatellaceae, Synechococcales, Cyanobacteria) based on four new species isolated from dryland soils including the coastal sage scrub near San Diego, California (USA), the Mojave and Colorado Deserts with sites at Joshua Tree National Park and Mojave National Preserve, California (USA), and the Atacama Desert (Chile). The genus is morphologically characterized by having thin trichomes (<4.5 µm wide), cells both shorter and longer than wide, rarely occurring single and double false branching, necridia appearing singly or in rows, and sheaths with a distinctive collar-like fraying and widening mid-filament, the feature for which the genus is named. The genus is morphologically nearly identical with Leptolyngbya sensu stricto but is phylogenetically quite distant from that genus. It is consequently a cryptic genus that will likely be differentiated in future studies based on 16S rRNA sequence data. The type species, T. maritimus sp. nov. is morphologically distinct from the other three species, T. coquimbo sp. nov., T. andrei sp. nov. and T. ladouxae sp. nov. However, these latter three species are morphologically very close and are considered by the authors to be cryptic species. All species are separated phylogenetically based on sequence of the 16S-23S ITS region. Three distinct ribosomal operons were recovered from the genus, lending difficulty to recognizing further diversity in this morphologically cryptic genus.


Asunto(s)
Cianobacterias , Ecosistema , Técnicas de Tipificación Bacteriana , Chile , Colorado , Cianobacterias/genética , ADN Bacteriano , Filogenia , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Suelo , Estados Unidos
14.
J Environ Sci Health B ; 56(3): 251-258, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33370160

RESUMEN

This study aimed to assess, in a microcosm condition, the efficacy of electrostatic spraying of herbicide imazamox in the control of Salvinia molesta and the effects of decomposition of plant material on water quality. The herbicide rates used were 600, 700, 800, and 900 g ai ha-1 and spray volume of 50 L ha-1 in electrostatic application. Control effectiveness was assessed at 7, 15, 30, 45, and 60 days after application (DAA), expressed in percentage (0-100%) of visible injury symptoms in the plants, biochemical oxygen demand (BOD5), chemical oxygen demand (COD), chlorophyll a and pheophytin a contents at 0, 7, 15, 30, 45, and 60 DAA, and fresh and dry biomass at 60 DAA. Imazamox was effective in controlling 63% of S. molesta with 900 g ai ha-1 in 45 DAA and 30% with 800 g ai ha-1 in 30 DAA, and reduced 82.3% and 17.5% of fresh weight and 62.6% and 9.3% of dry weight of plant at 60 DAA, respectively. The imazamox spray reduced chlorophyll a with all doses applied and increased BOD5 in 45 DAA with 900 g ai ha-1 and COD in all assessment periods, but for temperature, dissolved oxygen, electrical conductivity, and pH, there was no significant effect after spraying. The herbicide imazamox reduced S. molesta plants with 900 g ai ha-1, without causing significant effects on environmental indicators of water quality. Electrostatic spraying of herbicide can be used in management strategies of aquatic plants to reduce plant density in water bodies and maintain the colonization of plants at a level not harmful to the aquatic biota.


Asunto(s)
Herbicidas/farmacología , Imidazoles/farmacología , Tracheophyta/efectos de los fármacos , Calidad del Agua , Análisis de la Demanda Biológica de Oxígeno , Biomasa , Clorofila A/metabolismo , Relación Dosis-Respuesta a Droga , Indicadores Ambientales , Herbicidas/administración & dosificación , Imidazoles/administración & dosificación , Electricidad Estática , Temperatura , Tracheophyta/metabolismo
15.
J Environ Sci Health B ; 56(11): 941-947, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34554046

RESUMEN

The aim of this study was to assess the efficacy of imazamox for control of S. molesta and to assess the effects of plant decomposition on environmental indicators after application of this herbicide in microcosm conditions. The following rates were used: 600, 700, 800 and 900 g ai ha-1 and spray volume 50 L ha-1. Control efficacy was determined as the percentage (from 0 to 100%) of visible injury symptoms in the plants, biochemical and chemical oxygen demand (BOD5 and COD), water quality variables, chlorophyll a and pheophytin a at 0, 7, 15, 30, 45 and 60 days after application (DAA) and fresh and dry biomass at 60 DAA. Imazamox was effective in controlling 94% of S. molesta with 900 g ai ha-1; it reduced 95% of fresh weight and 92% of dry weight of plant at 60 DAA, and reduced chlorophyll a of the plants for all rates. For BOD5, there was an increase for all rates at 15, 30 and 45 DAA with restoration of the parameters at 60 DAA, and for COD, there was an increase at 60 DAA with 700 and 900 g ai ha-1. For temperature, pH, dissolved oxygen and electrical conductivity, there was no significant effect after spraying. Imazamox was effective in controlling S. molesta with 900 g ai ha-1 without causing significant effects on the physical-chemical parameters of water quality.


Asunto(s)
Indicadores Ambientales , Tracheophyta , Clorofila A , Imidazoles
16.
Fungal Genet Biol ; 134: 103281, 2020 01.
Artículo en Inglés | MEDLINE | ID: mdl-31626987

RESUMEN

Cadmium (Cd) is a heavy metal present in the environment mainly as a result of industrial contamination that can cause toxic effects to life. Some microorganisms, as Trichoderma harzianum, a fungus used in biocontrol, are able to survive in polluted environments and act as bioremediators. Aspects about the tolerance to the metal have been widely studied in other fungi although there are a few reports about the response of T. harzianum. In this study, we determined the effects of cadmium over growth of T. harzianum and used RNA-Seq to identify significant genes and processes regulated in the metal presence. Cadmium inhibited the fungus growth proportionally to its concentration although the fungus exhibited tolerance as it continued to grow, even in the highest concentrations used. A total of 3767 (1993 up and 1774 down) and 2986 (1606 up and 1380 down) differentially expressed genes were detected in the mycelium of T. harzianum cultivated in the presence of 1.0 mg mL-1 or 2.0 mg mL-1 of CdCl2, respectively, compared to the absence of the metal. Of these, 2562 were common to both treatments. Biological processes related to cellular homeostasis, transcription initiation, sulfur compound biosynthetic and metabolic processes, RNA processing, protein modification and vesicle-mediated transport were up-regulated. Carbohydrate metabolic processes were down-regulated. Pathway enrichment analysis indicated induction of glutathione and its precursor's metabolism. Interestingly, it also indicated an intense transcriptional induction, especially by up-regulation of spliceosome components. Carbohydrate metabolism was repressed, especially the mycoparasitism-related genes, suggesting that the mycoparasitic ability of T. harzianum could be affected during cadmium exposure. These results contribute to the advance of the current knowledge about the response of T. harzianum to cadmium exposure and provide significant targets for biotechnological improvement of this fungus as a bioremediator and a biocontrol agent.


Asunto(s)
Cadmio/farmacología , Regulación Fúngica de la Expresión Génica/efectos de los fármacos , Genes Fúngicos , Hypocreales/efectos de los fármacos , Hypocreales/genética , Transcriptoma/efectos de los fármacos , Metabolismo de los Hidratos de Carbono/genética , Hypocreales/crecimiento & desarrollo , Micelio/efectos de los fármacos , Micelio/genética , Micelio/crecimiento & desarrollo , Modificación Traduccional de las Proteínas/efectos de los fármacos , Procesamiento Postranscripcional del ARN/efectos de los fármacos , Empalmosomas/efectos de los fármacos
17.
J Chem Inf Model ; 60(2): 667-683, 2020 02 24.
Artículo en Inglés | MEDLINE | ID: mdl-31922754

RESUMEN

Protein-peptide interactions play a crucial role in many cellular and biological functions, which justify the increasing interest in the development of peptide-based drugs. However, predicting experimental binding modes and affinities in protein-peptide docking remains a great challenge for most docking programs due to some particularities of this class of ligands, such as the high degree of flexibility. In this paper, we present the performance of the DockThor program on the LEADS-PEP data set, a benchmarking set composed of 53 diverse protein-peptide complexes with peptides ranging from 3 to 12 residues and with up to 51 rotatable bonds. The DockThor performance for pose prediction on redocking studies was compared with some state-of-the-art docking programs that were also evaluated on the LEADS-PEP data set, AutoDock, AutoDock Vina, Surflex, GOLD, Glide, rDock, and DINC, as well as with the task-specific docking protocol HPepDock. Our results indicate that DockThor could dock 40% of the cases with an overall backbone RMSD below 2.5 Å when the top-scored docking pose was considered, exhibiting similar results to Glide and outperforming other protein-ligand docking programs, whereas rDock and HPepDock achieved superior results. Assessing the docking poses closest to the crystal structure (i.e., best-RMSD pose), DockThor achieved a success rate of 60% in pose prediction. Due to the great overall performance of handling peptidic compounds, the DockThor program can be considered as suitable for docking highly flexible and challenging ligands, with up to 40 rotatable bonds. DockThor is freely available as a virtual screening Web server at https://www.dockthor.lncc.br/ .


Asunto(s)
Simulación del Acoplamiento Molecular , Péptidos/metabolismo , Proteínas/metabolismo , Benchmarking , Ligandos , Péptidos/química , Conformación Proteica , Proteínas/química
18.
Adv Physiol Educ ; 44(2): 124-130, 2020 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-32108512

RESUMEN

The search for more efficient teaching methodologies is a great challenge for Brazilian educators, since most classes are still traditional (theoretical) and have little student involvement during the learning process. Active learning methodologies, where students play a central role in the learning process, are proving to be more effective and interesting when it comes to acquiring knowledge. Thus we decided to develop an innovative technique for teaching Human Endocrine Physiology, called "Endocrine Circuit." The circuit consisted of eight stations in which students were asked to organize a scheme with cards to answer a specific question about a gland or tissue with endocrine relevance. The effectiveness of the developed activity was validated through a pretest-posttest design, in which the students had to answer a 10-question test. We found out that, after the Endocrine Circuit application, students showed an improvement in the percentage of correct answers for 7 out of 10 questions contained in the questionnaire (P ≤ 0.05). In addition, the activity showed positive outcomes regarding student's engagement in this study, besides showing to be more efficient than the Brazilian traditional theoretical classes.


Asunto(s)
Comprensión , Evaluación Educacional/métodos , Sistema Endocrino/fisiología , Fisiología/educación , Aprendizaje Basado en Problemas/métodos , Brasil , Humanos
19.
Am Heart J ; 215: 187-197, 2019 09.
Artículo en Inglés | MEDLINE | ID: mdl-31349110

RESUMEN

BACKGROUND: Appropriate dietary recommendations represent a key part of secondary prevention in cardiovascular disease (CVD). We evaluated the effectiveness of the implementation of a nutritional program on quality of diet, cardiovascular events, and death in patients with established CVD. METHODS: In this open-label, multicenter trial conducted in 35 sites in Brazil, we randomly assigned (1:1) patients aged 45 years or older to receive either the BALANCE Program (experimental group) or conventional nutrition advice (control group). The BALANCE Program included a unique nutritional education strategy to implement recommendations from guidelines, adapted to the use of affordable and regional foods. Adherence to diet was evaluated by the modified Alternative Healthy Eating Index. The primary end point was a composite of all-cause mortality, cardiovascular death, cardiac arrest, myocardial infarction, stroke, myocardial revascularization, amputation, or hospitalization for unstable angina. Secondary end points included biochemical and anthropometric data, and blood pressure levels. RESULTS: From March 5, 2013, to Abril 7, 2015, a total of 2534 eligible patients were randomly assigned to either the BALANCE Program group (n = 1,266) or the control group (n = 1,268) and were followed up for a median of 3.5 years. In total, 235 (9.3%) participants had been lost to follow-up. After 3 years of follow-up, mean modified Alternative Healthy Eating Index (scale 0-70) was only slightly higher in the BALANCE group versus the control group (26.2 ±â€¯8.4 vs 24.7 ±â€¯8.6, P < .01), mainly due to a 0.5-serving/d greater intake of fruits and of vegetables in the BALANCE group. Primary end point events occurred in 236 participants (18.8%) in the BALANCE group and in 207 participants (16.4%) in the control group (hazard ratio, 1.15; 95% CI 0.95-1.38; P = .15). Secondary end points did not differ between groups after follow-up. CONCLUSIONS: The BALANCE Program only slightly improved adherence to a healthy diet in patients with established CVD and had no significant effect on the incidence of cardiovascular events or death.


Asunto(s)
Enfermedades Cardiovasculares/prevención & control , Dieta/normas , Programas Nacionales de Salud/normas , Evaluación Nutricional , Estado Nutricional , Desarrollo de Programa/métodos , Prevención Secundaria/métodos , Brasil/epidemiología , Enfermedades Cardiovasculares/epidemiología , Causas de Muerte/tendencias , Femenino , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Factores de Riesgo , Tasa de Supervivencia/tendencias
20.
J Phycol ; 55(5): 976-996, 2019 10.
Artículo en Inglés | MEDLINE | ID: mdl-31233617

RESUMEN

Soil cyanobacteria are crucial components of biological soil crusts and carry out many functions in dryland ecosystems. Despite this importance, their taxonomy and population genetics remain poorly known. We isolated 42 strains of simple filamentous cyanobacteria previously identified as Pseudophormidium hollerbachianum from 26 desert locations in the North and South America and characterized these strains using a total evidence approach, that is, using both morphological and molecular data to arrive at taxonomic decisions. Based on a phylogenetic analysis of 16S rRNA gene sequences, we propose and characterize Myxacorys gen. nov. with two new species Myxacorys chilensis, the generitype, and M. californica. We also found distinct 16S-23S ITS sequence variability within species in our dataset. Especially interesting was the presence of two distinct lineages of M. californica obtained from locations in close spatial proximity (within a few meters to kilometers from each other) suggesting niche differentiation. The detection of such unrecognized lineage-level variability in soil cyanobacteria has important implications for biocrust restoration practices and conservation efforts.


Asunto(s)
Cianobacterias , Ecosistema , Américas , Filogenia , ARN Ribosómico 16S , Análisis de Secuencia de ADN , Microbiología del Suelo , América del Sur
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA