Bioactivities from marine algae of the genus Gracilaria de Almeida, Cynthia Layse F; Falcão, Heloina de S; Lima, Gedson R de M ...
International Journal of Molecular Sciences,
07/2011, Letnik:
12, Številka:
7
Journal Article, Book Review
Recenzirano
Odprti dostop
Seaweeds are an important source of bioactive metabolites for the pharmaceutical industry in drug development. Many of these compounds are used to treat diseases like cancer, acquired ...immune-deficiency syndrome (AIDS), inflammation, pain, arthritis, as well as viral, bacterial, and fungal infections. This paper offers a survey of the literature for Gracilaria algae extracts with biological activity, and identifies avenues for future research. Nineteen species of this genus that were tested for antibacterial, antiviral, antifungal, antihypertensive, cytotoxic, spermicidal, embriotoxic, and anti-inflammatory activities are cited from the 121 references consulted.
Enzymatic biocatalysis is a sustainable technology. Enzymes are versatile and highly efficient biocatalysts, and have been widely employed due to their biodegradable nature. However, because the ...three-dimensional structure of these enzymes is predominantly maintained by weaker non-covalent interactions, external conditions, such as temperature and pH variations, as well as the presence of chemical compounds, can modify or even neutralize their biological activity. The enablement of this category of processes is the result of the several advances in the areas of molecular biology and biotechnology achieved over the past two decades. In this scenario, metal–organic frameworks (MOFs) are highlighted as efficient supports for enzyme immobilization. They can be used to ‘house’ a specific enzyme, providing it with protection from environmental influences. This review discusses MOFs as structures; emphasizes their synthesis strategies, properties, and applications; explores the existing methods of using immobilization processes of various enzymes; and lists their possible chemical modifications and combinations with other compounds to formulate the ideal supports for a given application.
Radioactive ^{27}Mg (t_{1/2}=9.5 min) was implanted into GaN of different doping types at CERN's ISOLDE facility and its lattice site determined via β^{-} emission channeling. Following ...implantations between room temperature and 800 °C, the majority of ^{27}Mg occupies the substitutional Ga sites; however, below 350 °C significant fractions were also found on interstitial positions ∼0.6 Å from ideal octahedral sites. The interstitial fraction of Mg was correlated with the GaN doping character, being highest (up to 31%) in samples doped p type with 2×10^{19} cm^{-3} stable Mg during epilayer growth, and lowest in Si-doped n-GaN, thus giving direct evidence for the amphoteric character of Mg. Implanting above 350 °C converts interstitial ^{27}Mg to substitutional Ga sites, which allows estimating the activation energy for migration of interstitial Mg as between 1.3 and 2.0 eV.
Since December 2016, Brazil has experienced an unusually large outbreak of yellow fever (YF). Whether urban transmission may contribute to the extent of the outbreak is unclear. The objective of this ...study was to characterize YF virus (YFV) genomes and to identify spatial patterns to determine the distribution and origin of YF cases in Minas Gerais, Espírito Santo and Rio de Janeiro, the most affected Brazilian states during the current YFV outbreak.
We characterized near-complete YFV genomes from 14 human cases and two nonhuman primates (NHP), sampled from February to April 2017, retrieved epidemiologic data of cases and used a geographic information system to investigate the geospatial spread of YFV.
All YFV strains were closely related. On the basis of signature mutations, we identified two cocirculating YFV clusters. One was restricted to the hinterland of Espírito Santo state, and another formed a coastal cluster encompassing several hundred kilometers. Both clusters comprised strains from humans living in rural areas and NHP. Another NHP lineage clustered in a basal relationship. No signs of adaptation of YFV strains to human hosts were detected.
Our data suggest sylvatic transmission during the current outbreak. Additionally, cocirculation of two distinct YFV clades occurring in humans and NHP suggests the existence of multiple sylvatic transmission cycles. Increased detection of YFV might be facilitated by raised awareness for arbovirus-mediated disease after Zika and chikungunya virus outbreaks. Further surveillance is required, as reemergence of YFV from NHPs might continue and facilitate the appearance of urban transmission cycles.
Objectives
Characterize the cell profile and immunostaining of proinflammatory markers in an experimental model of bisphosphonate‐related osteonecrosis of the jaw (BRONJ).
Materials and Methods
Male ...Wistar rats (n = 6–7) were treated chronically with saline solution or zoledronic acid (ZA) at 0.04, 0.20, and 1.00 mg kg−1 (1.4 × 10−7, 6.9 × 10−6, and 3.4 × 10−5 mol kg−1), and subsequently, the first left inferior molar was extracted. Were performed counting of viable and empty osteocyte lacunae, viable and apoptotic osteoclasts, polymorphonuclear neutrophil, mast cells (toluidine blue), and the positive presence cells for CD68, tumor necrosis factor‐alpha (TNF‐α), IL (interleukin)‐1β, inducible nitric oxide synthase (iNOS), nuclear factor‐kappa B (NF‐kB) and IL‐18 binding protein (IL‐18 bp).
Results
BRONJ was showed in ZA treated with 0.20 and 1.00 mg kg−1. There is a dose dependent increase in percentage of empty osteocyte lacunae (P < 0.001) and apoptotic osteoclasts (P < 0.001), counting of total osteoclasts (P = 0.003), polymorphonuclear neutrophil cells (P = 0.009), cytoplasmic‐positive cells of CD68 (P < 0.001), TNF‐α (P = 0.001), IL‐1β (P = 0.001), iNOS (P < 0.001), NF‐kB (P = 0.006), and nuclear‐positive cells of NF‐kB (P = 0.011). Consequently, there is no difference in mast cells (P = 0.957), and IL‐18 bp immunostaining decreases dose dependently (P = 0.005).
Conclusions
BRONJ is characterized by increases in immunostaining for proinflammatory markers and NF‐kB and inversely associated with cells exhibiting IL‐18 bp.
Objective. We compared the effects of transcranial direct current stimulation at different cortical sites (premotor and motor primary cortex) combined with constraint-induced movement therapy for ...treatment of stroke patients. Design. Sixty patients were randomly distributed into 3 groups: Group A, anodal stimulation on premotor cortex and constraint-induced movement therapy; Group B, anodal stimulation on primary motor cortex and constraint-induced movement therapy; Group C, sham stimulation and constraint-induced movement therapy. Evaluations involved analysis of functional independence, motor recovery, spasticity, gross motor function, and muscle strength. Results. A significant improvement in primary outcome (functional independence) after treatment in the premotor group followed by primary motor group and sham group was observed. The same pattern of improvement was highlighted among all secondary outcome measures regarding the superior performance of the premotor group over primary motor and sham groups. Conclusions. Premotor cortex can contribute to motor function in patients with severe functional disabilities in early stages of stroke. This study was registered in ClinicalTrials.gov database (NCT 02628561).
Chagas disease is caused by the protozoan Trypanosoma cruzi, affecting around 8 million people worldwide. After host cell invasion, the infective trypomastigote form remains 2-4 hours inside acidic ...phagolysosomes to differentiate into replicative amastigote form. In vitro acidic-pH-induced axenic amastigogenesis was used here to study this step of the parasite life cycle. After three hours of trypomastigote incubation in amastigogenesis promoting acidic medium (pH 5.0) or control physiological pH (7.4) medium samples were subjected to three rounds of centrifugation followed by ultrafiltration of the supernatants. The resulting exoproteome samples were trypsin digested and analysed by nano flow liquid chromatography coupled to tandem mass spectrometry. Computational protein identification searches yielded 271 and 483 protein groups in the exoproteome at pH 7.4 and pH 5.0, respectively, with 180 common proteins between both conditions. The total amount and diversity of proteins released by parasites almost doubled upon acidic incubation compared to control. Overall, 76.5% of proteins were predicted to be secreted by classical or non-classical pathways and 35.1% of these proteins have predicted transmembrane domains. Classical secretory pathway analysis showed an increased number of mucins and mucin-associated surface proteins after acidic incubation. However, the number of released trans-sialidases and surface GP63 peptidases was higher at pH 7.4. Trans-sialidases and mucins are anchored to the membrane and exhibit an enzyme-substrate relationship. In general, mucins are glycoproteins with immunomodulatory functions in Chagas disease, present mainly in the epimastigote and trypomastigote surfaces and could be enzymatically cleaved and released in the phagolysosome during amastigogenesis. Moreover, evidence for flagella discard during amastigogenesis are addressed. This study provides the first comparative analysis of the exoproteome during amastigogenesis, and the presented data evidence the dynamism of its profile in response to acidic pH-induced differentiation.
► This study compared soil quality indices based on 3 sets of indicators. ► The effects of land management practices on soil functions were evaluated. ► Soil quality was best assessed using a set of ...29 indicators. ► However, fewer-indicators sets (8 and 4) showed the same trends. ► Soil quality index approach provides great information for land management decisions.
Efforts to define and quantify soil quality are not new, but establishing consensus about a set of standardized indicators remains difficult. Also, the view of land managers is usually not taken into account when evaluating various sets of indicators. Our objective was to compare, in functional terms, soil quality assessments based on 29 indicators, a subset with 8 of those indicators, and 4 indicators selected independently by farmers, based on their perceptions of soil quality. The assessments were made for three different rice management systems in Camaquã, Rio Grande do Sul state, Brazil, on soils of four soil textural classes based on clay content (<200, 200–400, 400–600, or >600gkg−1). The effects of land management practices on soil functions (water infiltration, storage and supply; nutrient storage, supply and cycling; and sustained biological activity) were evaluated. Soil quality was best assessed using the entire set of 29 indicators, but use of smaller indicator sets showed the same trends among management systems, textural classes, and soil functions, thus providing meaningful information on soil quality for land managers.
Aim
The goal of this study was to increase knowledge about the antimicrobial activity of some synthetic Riparin‐derived compounds, alone or in combination with fluoroquinolone antibiotics, against a ...strain of Staphylococcus aureus resistant to fluoroquinolone by way of overexpression of the NorA efflux pump.
Methods and Results
Microdilution tests showed that Riparins A and B did not show any significant antibacterial activity against Staph. aureus strains. On the other hand, the intrinsic antibacterial activity increased with increasing lipophilicity of the compounds, in the following order: Riparin‐D (MIC 256 μg ml−1; Log P 2·95) < Riparin‐C (MIC 102 μg ml−1; Log P 3·22) < Riparin‐E (MIC 16 μg ml−1; Log P 3·57). The addition of all riparins to growth media at subinhibitory concentrations caused an increase in the antibacterial activity of antibiotics against the NorA‐overexpressing test strain. Riparin‐B, which has two methoxyl groups at the phenethyl moiety, showed the best modulatory effect.
Conclusions
Riparin‐E is a good anti‐staphylococci agent, while Riparin‐B functions as a NorA efflux pump inhibitor.
Significance and Impact of the Study
Our data suggest the possibility of using Riparin‐B in combination with norfloxacin or ciprofloxacin for therapy of infections caused by multi‐drug resistant Staph. aureus.
The present study focused on the scenario of confirmed cases of SARS-CoV-2 infection in the state of Minas Gerais (MG), Brazil, from March 2020 to March 2021. We evaluated the evolution of COVID-19 ...prevalence and death in one municipality from each of the 14 health macro-regions of MG state. Socio-demographic characteristics and variables related to the municipalities were analyzed. The raw dataset used in this study was freely sourced from the website Brasil.io. From the raw dataset, two time series were extracted: the cumulative confirmed cases of COVID-19 and cumulative death counts, and they were compared to the state data using a nowcasting approach. In order to make time series comparisons possible, all data was normalized per 100,000 inhabitants. When analyzing in light of colored wave code interventions initiated in August 2020 in MG, for the majority of the municipalities, there was an absence of clear influence on prevalence and deaths. The national holidays in the first semester of 2020 had a small impact on the COVID-19 prevalence of the municipalities, but the holidays in the second semester of 2020 and beginning of 2021 caused important impacts on COVID-19 prevalence. The low number of ICU beds in some municipalities contributed to the higher number of deaths. The analysis showed here is expected to contribute to the improvement of decision making of the MG government, as it opened a huge possibility to have the total macro-regions and state data analyzed. Key words: SARS-CoV-2; Epidemiology; Prevalence; ICU beds; Pandemic; Time series analysis
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