•Effect of different solvents on the morphology of electrospun Pull was evaluated.•Pull nanofibers was produced with water, DMF and their mixtures (30 wt.% of DMSO).•The best solvents with the ...smallest fiber diameter was DMF/DMSO (70/30 wt.%).•The entrapment of curcumin in the Pull nanofibers was efficient.•The results obtained created new approaches applications for drug delivery systems.
In this work, the effect of different solvents and solvent binary mixtures on the morphology of electrospun pullulan (Pull) nanofibers was evaluated. The solution viscosities, interactions between solvent and polymer, as well as, solvent vapor pressure, were correlated to the morphology and diameters of the nanofibers. Water, dimethylformamide (DMF) and dimethyl sulfoxide (DMSO) and Teas graphs that rely on the use of Hildebrand solubility parameters were used to identify the most suitable mixtures of solvents. The best binary mixture of solvents to produce Pull nanofibers without defects and with small diameters (203±32 nm) was DMF/DMSO in the ratio of 70/30 wt.%. Pull nanofibers containing 3 and 5 wt. % of curcumin (Curc) in a mixture of DMF/DMSO (70/30 wt.%) were then obtained, and the entrapment efficiency was evaluated using 1H NMR and a UV-–vis spectrophotometer. The results obtained in this work create a new approach for the production of Pull nanofibers for drug delivery systems.
Background
Paclitaxel (PCX) is the first‐line choice for the treatment of several types of cancer, including breast, ovarian, and lung cancers. However, patients who receive even a single dose with ...PCX commonly develop mechanical and cold allodynia, a symptom known as PCX‐associated acute pain syndrome (P‐APS). Here, we assessed possible involvement of kinin–kallikrein and renin‐angiotensin systems in P‐APS in mice.
Methods
Male mice C57Bl/6 wild type (WT) and knockouts for bradykinin receptors, B1 (B1−/−) and B2 (B2−/−), were used. Mechanical and cold allodynia were evaluated by using von Frey filaments and acetone test, respectively. P‐APS was induced by administration of PCX 4 mg/kg, i.v.. ACE inhibitors (captopril and enalapril), antagonists for angiotensin II type 1 (losartan) and type 2 (AT2R; PD123319 and EMA 401) receptors were administrated prior the treatment with PCX. RT‐PCR was used to analyse the expression of mRNA for B1, B2 and AT2R receptors.
Results
Administration of PCX in B1−/− and B2−/− mice induced lower mechanical and cold allodynia compared to the WT. However, the pre‐treatment with ACE inhibitors reduced the development of mechanical and cold allodynia in P‐APS. Surprisingly, we found that mice pre‐treatment with the PD123319 or EMA401, but not losartan, prevented the development of mechanical and cold allodynia induced by PCX.
Conclusion
Our results demonstrated the involvement of bradykinin receptors B1 and B2 as well as AT2R in the induction of P‐APS in mice, and suggest the use of AT2R antagonists as a potential therapy for the prevention of P‐APS in humans.
Significance
Kinin–kallikrein and renin‐angiotensin systems, through B1, B2 and AT2 receptors, potentiates paclitaxel‐associated acute pain syndrome (P‐APS) in mice. Antagonists for AT2R are potential alternatives to prevent P‐APS.
•Three different tree biodiversity rapid assessment methods for cocoa fields tested.•A stepwise approach with stakeholder engagement was used to evaluate results.•Method with similar size plots set ...up on four directions was the most accurate.•The method can be applied at large-scale with few resources to collect data.•Farmers can report accurately on tree species and participate in data collection.
Biodiversity is recognized as an essential part of sustainable development efforts, however reducing biodiversity loss is a key global challenge that requires updated data on biodiversity status at different scales. Cocoa agroforests include tree species besides cocoa, a practice beneficial to biodiversity, ecosystem conservation and farming households. We present a stepwise procedure to test and select a method that rapidly assesses biodiversity in cocoa agroforests based primarily on species richness and counts of non-cocoa trees. Three rapid assessment methodologies (RapidBAM) with different sampling procedures were tested in three phases: calibration, testing and evaluation. Results showed the method using the lowest number of sample plots with a minimum area coverage and a consistent sampling time (regardless of farm context) provided the most accurate and straightforward assessment. Farmers accurately reported qualitatively on species, complimenting quantitative data produced by RapidBAM. Collecting biodiversity data with RapidBAM proved valuable to collect data at large-scales and is applicable to different landscapes. Monitoring biodiversity with fewer required resources than conventional methods is a relevant outcome, which can help defining efficient biodiversity-friendly farming practices.
Behavioral evidence of impaired response inhibition (RI) and hyperactive error monitoring (EM) in obsessive-compulsive disorder (OCD) is inconsistent. Recent neuroimaging work suggests that EM plays ...a role in RI impairments in OCD, but this has rarely been investigated using behavioral measures. The aims of this study were to (1) compare RI and EM performance between adults with OCD and non-psychiatric controls (NPC) while investigating possible moderators, and (2) assess whether excessive EM influences RI in OCD. We compared RI and EM performance on the Stop-Signal Task (SST) between 92 adults with OCD and 65 NPC from two Brazilian sites. We used linear regression to investigate which variables (group, age, medication use, clinical symptomatology) influenced performance, as well as to examine possible associations between RI and EM. OCD and NPC did not differ in RI and EM. However, age moderated RI performance in OCD with a medium effect size, reflecting differential effects of age on RI between groups: age was positively associated with RI in OCD but not NPC. Further, OCD severity predicted EM with a medium to large effect size, suggesting that more symptomatic patients showed greater monitoring of their mistakes. Finally, group moderated the relationship between RI and EM with a small effect size. Our findings suggest that demographic factors may influence RI, whereas clinical factors may influence EM. Further, we found preliminary behavioral evidence to indicate that impaired RI and excessive EM are related in OCD.
BRAZIL ROAD-KILL Grilo, Clara; Coimbra, Michely R.; Cerqueira, Rafaela C. ...
Ecology,
11/2018, Volume:
99, Issue:
11
Journal Article
Peer reviewed
Open access
Mortality from collision with vehicles is the most visible impact of road traffic on wildlife. Mortality due to roads (hereafter road-kill) can affect the dynamic of populations of many species and ...can, therefore, increase the risk of local decline or extinction. This is especially true in Brazil, where plans for road network upgrading and expansion overlaps biodiversity hotspot areas, which are of high importance for global conservation. Researchers, conservationists and road planners face the challenge to define a national strategy for road mitigation and wildlife conservation. The main goal of this dataset is a compilation of geo-referenced road-kill data from published and unpublished road surveys. This is the first Data Paper in the BRAZIL series (see ATLANTIC, NEOTROPICAL, and BRAZIL collections of Data Papers published in Ecology), which aims make public road-kill data for species in the Brazilian Regions. The dataset encompasses road-kill records from 45 personal communications and 26 studies published in peer-reviewed journals, theses and reports. The road-kill dataset comprises 21,512 records, 83% of which are identified to the species level (n = 450 species). The dataset includes records of 31 amphibian species, 90 reptile species, 229 bird species, and 99 mammal species. One species is classified as Endangered, eight as Vulnerable and twelve as Near Threatened. The species with the highest number of records are: Didelphis albiventris (n = 1,549), Volatinia jacarina (n = 1,238), Cerdocyon thous (n = 1,135), Helicops infrataeniatus (n = 802), and Rhinella icterica (n = 692). Most of the records came from southern Brazil. However, observations of the road-kill incidence for non-Least Concern species are more spread across the country. This dataset can be used to identify which taxa seems to be vulnerable to traffic, analyze temporal and spatial patterns of road-kill at local, regional and national scales and also used to understand the effects of road-kill on population persistence. It may also contribute to studies that aims to understand the influence of landscape and environmental influences on road-kills, improve our knowledge on road-related strategies on biodiversity conservation and be used as complementary information on large-scale and macroecological studies. No copyright or proprietary restrictions are associated with the use of this data set other than citation of this Data Paper.
The aim of this study was to assess and compare the effects of laser phototherapy (LPT) on cutaneous flaps on diabetic rats.
Diabetes mellitus is characterized by high blood glucose levels. Its main ...complications are delayed wound healing, an impaired blood supply, and a decrease in collagen production. Cutaneous flaps are routinely used in several surgical procedures, and most failures are related to poor blood supply. LPT has been studied using several healing models.
Twelve Wistar rats were randomized into three groups: group 1 (G1; diabetic animals without treatment), group 2 (G2; diabetic animals irradiated with lambda680 nm), and group 3 (G3; diabetic animals irradiated with lambda790 nm). Diabetes was induced with streptozotocin. A 2- x 8-cm cutaneous flap was raised on the dorsum of each animal, and a plastic sheet was introduced between the flap and the bed to cause poor blood supply. Nonirradiated animals acted as controls. The dose per session was 40 J/cm(2). Laser light was applied transcutaneously and fractioned on 16 contact points at the wound margins (16 x 2.5 J/cm(2)). Animal death occurred on day 8 after surgery. Specimens were taken, processed, cut, stained with eosin (HE) and sirius red, and underwent histological analysis.
It is shown that accute inflammation was mostly discrete for G3. Chronic inflammation was more evident for G2. Fibroblast number was higher for G3. Angiogenesis was more evident for G3. Necrosis was more evident for G2. Statistical analysis among all groups showed significant differences (p = 0.04) on the level of acute inflammation between G1 and G3, tissue necrosis between G1 and G2 (p = 0.03), chronic inflammation between (p = 0.04), fibroblastic proliferation between G2 and G3 (p = 0.05), and neovascularization between G2 and G3 (p = 0.04).
LPT was effective in increasing angiogenesis as seen on irradiated subjects and was more pronounced when IR laser light was used.
The influence of granulometry and organic treatment of a Brazilian montmorillonite (MMT) clay on the synthesis and properties of poly(styrene-co-n-butyl acrylate)/layered silicate nanocomposites was ...studied. Hybrid latexes of poly(styrene-co-butyl acrylate)/MMT were synthesized via miniemulsion polymerization using either sodium or organically modified MMT. Five clay granulometries ranging from clay particles smaller than 75 μm to colloidal size were selected. The size of the clay particles was evaluated by specific surface area measurements (BET). Cetyl trimethyl ammonium chloride was used as an organic modifier to enhance the clay compatibility with the monomer phase before polymerization and to improve the clay distribution and dispersion within the polymeric matrix after polymerization. The sodium and organically modified natural clays as well as the composites were characterized by X-ray diffraction analysis. The latexes were characterized by dynamic light scattering. The mechanical, thermal, and rheological properties of the composites obtained were characterized by dynamical-mechanical analysis, thermogravimetry, and small amplitude oscillatory shear tests, respectively. The results showed that smaller the size of the organically modified MMT, the higher the degree of exfoliation of nanoplatelets. Hybrid latexes in presence of Na-MMT resulted in materials with intercalated structures.
In this work hybrid latexes of poly(styrene‐co‐butyl acrylate)/montmorillonite were synthesized via miniemulsion polymerization using a Brazilian organically modified montmorillonite. The natural ...clay was previously treated with Cetyltrimethyl ammonium chloride (CTAC) in order to increase the interaction between the clay and the monomer phase. Three different methodologies to modify the clay and their influence on the final properties of the composites obtained were evaluated in this work. The modified clays were characterized by X‐ray diffraction (XRD). The films obtained after drying the latexes were characterized by dynamic‐mechanical thermal analyses (DMTA), small amplitude oscillatory shear (SAOS), transmission electronic microscopy (TEM) and Cobb test. The X‐ray diffractograms, showed an increase of basal spacing after organic treatment indicating the introduction of CTA+ within the clay interlamelar space. This interlamelar space was further increased after polymerization for all of the three differently modified clays studied, indicating that in situ polymerization occurred. The introduction of organically modified clays did not influence the kinetics of polymerization. Stable latexes were obtained. The DMTA presented improved mechanical properties for the materials charged with two of the modified clays studied when compared to a conventional composite. SAOS analysis revealed that an exfoliated structure might have been obtained when adding one of the modified clays to the reacting medium. Cobb tests showed that the permeability to water was reduced by the incorporation of clays to the copolymer.
Graphene-based composites are promising candidates to improve properties in flexible packaging to protect electronic devices. However, the literature hardly addresses the industrial scale ...requirements. In this context, high-density polyethylene (HDPE), a common packaging material, and an industrial grade graphene (G) were used to prepare multilayered composites by cast film coextrusion, a flexible-packaging-industry compatible technique. The effects of G content and surface finishing on HDPE films’ properties were investigated. Experimental results showed that a maximum permeability reduction of 43% at 0.5 wt% of G was achieved. Such result was associated with a good dispersion efficiency and with the filler’s aspect ratio. However, as the concentration of G increased both barrier and mechanical properties worsened due to a poor dispersion of G within the composite. Additionally, it was found that surface finishing induced defects increasing permeability despite improvements in visible light transmittance and reduction of surface roughness. These defects can be successfully prevented using a proper design of layers during coextrusion. In summary, the present study showed the feasibility of G-based flexible packaging film applications at an industrial scale. The importance of G dispersion and of layer design to achieve improved barrier properties should be emphasized.
Display omitted
•Industrial grade graphene can be used for flexible packaging applications.•0.5 wt% of industrial grade graphene reduced the oxygen permeability in 43%.•Layer design allows to overcome filler dispersion shortcomings.
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