A biobased monomer acrylated ricinoleic acid was synthesized from castor oil and copolymerized with methyl methacrylate in miniemulsion forming polymeric nanoparticles. The addition of the biobased ...monomer led to a decrease in the glass transition temperature of the copolymer and to the formation of a small fraction of gel, resulting in materials with interesting properties for future applications.
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•A biobased monomer acrylated ricinoleic acid was synthesized from castor oil.•The biobased monomer was copolymerized with methyl methacrylate in miniemulsion forming polymeric nanoparticles.•Polymers with lower Tgs were obtained with the addition of the biobased monomer.•The copolymers exhibited interesting properties for future applications as adhesives.
Vegetable oils-based polymers are promising materials with application in the industry of coatings and adhesives. Chemically-modified ricinoleic acid obtained from castor oil was used in this study to produce polymeric materials. The adopted strategy consisted in the epoxidation of the double bonds of ricinoleic acid, followed by the ring opening reaction in the presence of acrylic acid to form the acrylated ricinoleic acid (ARA). Free radical copolymerizations of ARA and methyl methacrylate (MMA) were carried out in miniemulsion, resulting in latexes stable over a long storage time. DLS measurements revealed the formation of submicron polymeric particles of different sizes strongly dependent on the fraction of the biobased monomer ARA, exhibiting diameters ranging from approximately 80nm to 150nm, as the ARA fraction was increased up to 80wt%. It was possible to prepare polymers with broad ranges of mass-average molar masses in the range from 1137kDa to 65kDa and glass transition temperatures lying in the interval from approximately 124°C–50°C by varying the concentration of the comonomer ARA. Crosslinked copolymers were obtained by increasing the proportion of ARA.
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GEOZS, IJS, IMTLJ, IZUM, KILJ, KISLJ, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
This study aimed to evaluate the behavioral and energy metabolism parameters in female mice subjected to obesity and offspring deprivation (OD) stress. Eighty female Swiss mice, 40 days old, were ...weighed and divided into two groups: Control group (control diet, n = 40) and Obese group (high-fat diet, n = 40), for induction of the animal model of obesity, the protocol was based on the consumption of a high-fat diet and lasted 8 weeks. Subsequently, the females were subjected to pregnancy, after the birth of the offspring, were divided again into the following groups (n = 20): Control non-deprived (ND), Control + OD, Obese ND, and Obese + OD, for induction of the stress protocol by OD. After the offspring were 21 days old, weaning was performed and the dams were subjected to behavioral tests. The animals were humanely sacrificed, the brain was removed, and brain structures were isolated to assess energy metabolism. Both obesity and OD led to anhedonia in the dams. It was shown that the structures most affected by obesity and OD are the hypothalamus and hippocampus, as evidenced by the mitochondrial dysfunction found in these structures. When analyzing the groups separately, it was observed that OD led to more pronounced mitochondrial damage; however, the association of obesity with OD, as well as obesity alone, also generated damage. Thus, it is concluded that obesity and OD lead to anhedonia in animals and to mitochondrial dysfunction in the hypothalamus and hippocampus, which may lead to losses in feeding control and cognition of the dams.
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•Obesity alters the number of births, sex and mortality of the offspring.•Obesity and offspring deprivation leads to anhedonia in matrices.•Obesity and offspring deprivation alter energy metabolism cerebral.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Polymer films made from cellulose esters are useful for embedding plant essential oils, either for food packaging or air freshener applications. Studies and testing were done on the physical and ...mechanical properties of cellulose ester-based films incorporating essential oils (EO) from lemongrass (Cybopogon citratus), rosemary pepper (Lippia sidoides) and basil (Ocimum gratissimum) at concentrations of 10 and 20% (v/w). Results obtained showed that, in all films, the addition of the essential oil caused a decrease in the water vapor permeability due to the hydrophobic nature of the oil. The use of 20% of EO caused lower transparency of the films, although the change was not observed visually. Mechanical testing was done on cellulose acetate, cellulose acetate propionate and cellulose acetate butyrate. It was found that incorporation of lemongrass, basil and rosemary pepper EO significantly affected the Young's modulus, tensile strength and elongation at break of the cellulose ester films. The results suggested that the essential oils interacted with the polymers like plasticizers. The results were confirmed with thermal and microscopic studies.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
•Septic patients usually display long-term neurocognitive impairment.•The neuroprotective role of a fish oil–rich emulsion was tested in septic rats.•Fish oil decreases markers of inflammation and ...oxidative damage at 24 h after sepsis.•Fish oil improves hippocampal and cortical levels of brain-derived neurotrophic factor 10 d after sepsis.•Fish oil ameliorates habituation and recognition memories 10 d after sepsis.
Sepsis is a severe organic dysfunction caused by an infection that affects the normal regulation of several organ systems, including the central nervous system. Inflammation and oxidative stress play crucial roles in the development of brain dysfunction in sepsis. The aim of this study was to determine the effect of a fish oil (FO)-55–enriched lipid emulsion as an important anti-inflammatory compound on brain dysfunction in septic rats.
Wistar rats were subjected to sepsis by cecal ligation and perforation (CLP) or sham (control) and treated orally with FO (600 µL/kg after CLP) or vehicle (saline; sal). Animals were divided into sham+sal, sham+FO, CLP+sal and CLP+FO groups. At 24 h and 10 d after surgery, the hippocampus, prefrontal cortex, and total cortex were obtained and assayed for levels of interleukin (IL)-1β and IL-10, blood–brain barrier permeability, nitrite/nitrate concentration, myeloperoxidase activity, thiobarbituric acid reactive species formation, protein carbonyls, superoxide dismutase and catalase activity, and brain-derived neurotrophic factor levels. Behavioral tasks were performed 10 d after surgery.
FO reduced BBB permeability in the prefrontal cortex and total cortex of septic rats, decreased IL-1β levels and protein carbonylation in all brain structures, and diminished myeloperoxidase activity in the hippocampus and prefrontal cortex. FO enhanced brain-derived neurotrophic factor levels in the hippocampus and prefrontal cortex and prevented cognitive impairment.
FO diminishes the negative effect of polymicrobial sepsis in the rat brain by reducing inflammatory and oxidative stress markers.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
The use of the anthelmintic levamisole as a cocaine adulterant has been increasing worldwide. Complications caused by this association include systemic vasculitis, agranulocytosis, neutropenia, ...tissue necrosis, pulmonary hemorrhage, and renal injury. Data about toxicity of levamisole are scarce, therefore the aim of this study was to evaluate the acute and subchronic toxic effects of levamisole in rats. Male Wistar rats received saline or levamisole by intraperitoneal route at the doses of 12, 24 and 36 mg/kg in the acute toxicity test; and at 3, 6 and 12 mg/kg in the subchronic toxicity test. Toxicity was evaluated using behavioral, cognitive, renal, hematological, biochemical and histopathological parameters. Acute administration of levamisole caused behavioral and histopathological alterations. Subchronic administration caused behavioral, cognitive and hematological alterations (p < 0.0001 and p < 0.05, respectively), impairment of liver and kidney functions (p < 0.05), and changes of antioxidant defenses (p ≤ 0.0001). Both administrations produced toxic effects of clinical relevance, which make levamisole a dangerous cutting agent. Furthermore, the knowledge of these effects can contribute to the correct diagnosis and treatment of cocaine dependents with unusual systemic alterations.
•The use of levamisole as a cocaine adulterant increased worldwide.•Several complications are associated with the concomitant use of these substances.•Data about the toxicology of levamisole are scarce.•Acute and subchronic administration of levamisole can cause toxic effects in rats.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Imidacloprid (IMI) is a neonicotinoid insecticide employed worldwide for crop protection. IMI’s mode of action occurs through the agonism of postsynaptic nicotinic acetylcholine receptors (nAChRs), ...with high specificity for insect nAChRs although there are reports of mammals’ toxicity. Studies on IMI’s neurotoxicity are not conclusive; therefore, the aim of this study was to evaluate the subchronic toxic effects of an IMI based commercial pesticide on rats. Adult male Wistar rats received an IMI suspension via the oral route at doses of 1.5, 5, and 15 mg/kg for 45 consecutive days. IMI caused an increase in rearing and time spent at the periphery in the locomotor activity test and a decrease in time spent to finish the OX maze task (p < 0.05; ANOVA/Bonferroni). In blood, there was a decrease in mean corpuscular hemoglobin and mean corpuscular hemoglobin concentration (p < 0.05; ANOVA/Bonferroni) and an increase in serum butyrylcholinesterase activity (p < 0.001; ANOVA/Bonferroni). Therefore, subchronic administration of an IMI-based-pesticide caused behavioral and systemic impairments in rats.
•Imidacloprid increased rearing in rats.•Imidacloprid increased time spent at the periphery in the locomotor activity test.•Imidacloprid decreased the time spent to finish the OX maze task.•Imidacloprid decreased mean corpuscular hemoglobin in rats.•Imidacloprid increased serum butyrylcholinesterase in rats.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Objective
Little is known about the positive predictive value of diagnostic tools for severe acute appendicitis (AA). Our objective was to study a retrospective cohort of patients with AA, ...emphasizing its laboratory and radiologic features, to establish risk factors for more severe cases of AA.
Methods
A retrospective cohort study with patients with AA confirmed by biopsy was performed. In each case, examinations were reviewed, data were compared, and laboratory and radiologic findings were established to identify risk factors for severe AA.
Results
During the studied period, 405 children, with a mean age of 120 months, were evaluated. Most of the patients were boys (63.2%). C-reactive protein was the best parameter for the diagnosis of perforated AA, with a sensitivity of 88% for values above 173 mg/dL. A total of 64.4% of the patients underwent abdominal ultrasound, and 26% had normal results.
Conclusions
Acute appendicitis is a disease with a wide spectrum of complications; thus, it is important to recognize the markers associated with severe cases of AA. High levels of C-reactive protein were the best markers associated with perforated appendicitis, and ultrasound was requested in most of the cases but was not helpful in most of them.
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