Resumo Os híbridos derivados de grafeno ou óxido de grafeno e o argilomineral montmorillonita são materiais cuja matriz do filossilicato oferece estabilização das camadas nanométricas das estruturas carbonáceas, além de melhoramento das propriedade físico-químicas e da biocompatibilidade. Por sua vez, o grafeno e seus derivados agregam novas funcionalidades à montmorillonita e ao aumento da reatividade. Os materiais funcionais resultantes do sinergismo entre os constituintes têm sido explorados em diferentes aplicações, como em processos de remediação ambiental por meio de adsorção e catálise, ciência de materiais, áreas biológicas e biomédicas. No âmbito dessa revisão, as principais rotas para obtenção dos híbridos de grafeno e derivados com montmorillonita são apresentadas, relacionando os fatores estruturais e interações entre os constituintes para formação dos compósitos. Ainda os principais métodos de caracterização são discutidos e as aplicações mais recentes são relacionadas às características estruturais, morfológicas, térmicas e texturais.

Abstract In hybrids derived from graphene or graphene oxide and montmorillonite (MMT) clay, the phyllosilicate matrix of MMT provides stability to the carbonaceous layer structure of graphene. The formation of hybrids improves the physicochemical properties and biocompatibility of the individual components. In addition to enhancing the chemical reactivity of MMT, the synthesis of hybrids with graphene or its derivatives may offer enhanced properties. The synergistic properties of the organic and inorganic components of the hybrids result in functional materials, as demonstrated in various fields, such as environmental remediation, adsorption, catalysis, materials science, biology, and biomedical sciences. In this review, we present the main routes for synthesizing the hybrids of graphene and its derivatives with MMT. We discuss the effects of the structure and interactions between the constituents on the formation of composites. Furthermore, major characterization techniques and material properties, such as structural, morphological, textural, and thermal properties, are discussed.

Hyptis crenata, commonly known as “salva-do-Marajó”, “hortelã-do-campo”, and “hortelãzinha”, is used in folk medicine in Northeast Brazil as tea or infusion to treat inflammatory diseases. Due to the pharmacological efficacy and the low toxicity of the essential oil of Hyptis crenata (EOHc), we decided to investigate the EOHc antiedematogenic effect in experimental models of inflammation. EOHc was administrated orally at doses of 10-300 mg/kg to male Swiss albino mice. Paw edema was induced by subcutaneous injection in the right hind paw of inflammatory stimuli (carrageenan, dextran, histamine, serotonin, and bradykinin) 60 min after administration of EOHc. EOHc significantly inhibited the induced edema. The inhibitory effect of EOHc on dextran-induced edema extended throughout the experimental time. For the 30, 100, and 300 mg/kg doses of EOHc, the inhibition was of 40.28±1.70, 51.18±2.69, and 59.24±2.13%, respectively. The EOHc inhibitory effect on carrageenan-induced edema started at 10 mg/kg at the second hour (h) and was maintained throughout the observation period. At 30, 100, and 300 mg/kg doses the inhibition started earlier, from 30 min. At the edema peak of 180 min, 56, 76, and 82% inhibition was observed for 30, 100, and 300 mg/kg doses, respectively. Additionally, the effect of EOHc on carrageenan-induced paw edema was influenced by the time of administration. The EOHc also inhibited myeloperoxidase activity. In conclusion, the EOHc showed a potent effect, both preventing and reversing the edema, consistent with its anti-inflammatory use in folk medicine.

ABSTRACT The biotechnology used in tendon, bone and joint recoveries in Equine Medicine has improved in recent years. The most used are platelet rich plasma and stem cells from adipose tissue and bone marrow. However, recent studies have shown that stem cells can be found in the bloodstream, also named peripheral blood progenitor cells (CPP). This note aims at reporting the feasibility of automated collection of CPP in horses. The procedure was conducted in an equine, female, Quarter Horses, 2 years old, 385kg. The automated collection of CPP was conducted using apheresis equipment Fresenius- Kabi coupled to C4Y kit. The procedure lasted two hours and 30 minutes without complications, processing 5054mL of whole blood and obtaining 351mL of CPP. Upon completion of the collection, the content of CPP was separated into 10 ml aliquots and immediately stored at -18°C. The automated technique proved to be feasible for horses, but needs improvement in order to achieve greater efficiency and reduce procedure time.

Actinomicetos são um dos principais produtores de enzimas, vitaminas e metabólitos secundários, destacando-se o gênero Streptomyces, o qual tem uma ampla capacidade de produção de antibióticos eficazes no combate a diferentes microrganismos, entre eles o Staphylococcus sp. Em virtude dessa eficiência no combate a patógenos, o objetivo deste trabalho foi avaliar a produção de metabólitos com atividade antimicrobiana produzidos por 67 Streptomyces isolados de liquens da região amazônica, ante isolados de mastite caprina (Staphylococcus aureus) do estado de Pernambuco, Brasil. Foi utilizado um planejamento fatorial para avaliar a influência das fontes de carbono (glicose) 0%, 0,5% e 1% e de nitrogênio (farinha de soja) 1%, 2,5% e 4% na produção dos antimicrobianos, bem como das variáveis pH, biomassa e atividade antimicrobiana. Dos Streptomyces estudados, o DPUA 1566 foi o que se destacou por formação de halos de inibição entre 18 e 26mm ante os isolados de mastite caprina. Foi possível verificar que a fonte de carbono inibiu a produção de antimicrobianos quando submetidos a uma concentração de glicose de 1%; com a retirada desta, os Streptomyces apresentaram uma elevada capacidade de produção de metabólitos com atividade antimicrobiana tendo potencial para o tratamento de mastite caprina.

Actinomycetes are a leading producer of enzymes, vitamins and secondary metabolites, especially the genus Streptomyces, which have a large capacity for the production of natural antibiotics and are effective against various micro-organisms including Staphylococcus sp. Due to this efficiency in combating micro-organisms, the aim of this study was to evaluate the production of metabolites with antimicrobial activity produced by Streptomyces isolated from lichens 67 in the Amazonia, compared to isolates from goat mastitis (Staphylococcus aureus) in the state of Pernambuco, Brazil. We used a complete factorial design to evaluate the influence of concentrations of carbon sources (glucose) at 0%, 0.5% and 1% and nitrogen (soybean flour) at 1%, 2.5% and 4% in the production of antimicrobial metabolites, and the influence of the pH, microbial biomass and activity variables. Of the studied Streptomyces DPUA 1566 what stood out was the formation of inhibition halos between 18 to 26 mm compared to the isolates from goats mastitis. It was noted that the carbon source inhibited the production of antimicrobial metabolites when subjected to a glucose concentration of 1%. However, after the discontinuation, Streptomyces showed a high capacity to produce metabolites with antimicrobial activity, which has an excellent potential for the treatment of mastitis in goats.

O presente artigo objetivou estudar a viabilidade da técnica de plasmaférese automatizada e padronizá-la em cinco equinos hígidos, bem como apresentar as complicações durante o procedimento, as adequações em relação aos procedimentos em humanos e avaliar a recuperação de volume globular e proteínas plasmáticas totais nos doadores. Os procedimentos foram realizados com o equipamento Fresenius AS104, com duração média de 1h46min, processamento de 5758mL de sangue total e colheita média de 3133mL de plasma. Não foram observadas alterações significativas do volume globular após a plasmaférese automatizada. A recuperação dos níveis plasmáticos de proteínas foi de 91,4% em 96 horas após o procedimento. A plasmaférese automatizada apresentou-se viável para a espécie equina, diminuindo o tempo de recuperação hematimétrica nos doadores.

This paper aimed to study feasibility and standardize the automated plasmapheresis in five healthy horses, showing the complications during the procedure, adjustments in relation to the procedures in humans and assessing the recovery of globular volume and plasma total proteins in donors. The procedures were performed with the Fresenius AS104 equipment, with an average duration of one hour and forty six minutes, processing 5758mL of whole blood and harvest average of 3133mL of plasma. There were no significant variations in globular volume after the automated plasmapheresis. The recovery of plasma total proteins was 91.4% at 96 hours after the procedure. The automated plasmapheresis appeared viable for the equine species, decreasing the time of hematimetric level recovery in donors.

Androgenic anabolic steroid, physical exercise and stress induce cardiovascular adaptations including increased endothelial function. The present study investigated the effects of these conditions alone and in combination on the vascular responses of male Wistar rats. Exercise was started at 8 weeks of life (60-min swimming sessions 5 days per week for 8 weeks, while carrying a 5% body-weight load). One group received nandrolone (5 mg/kg, twice per week for 8 weeks, im). Acute immobilization stress (2 h) was induced immediately before the experimental protocol. Curves for noradrenaline were obtained for thoracic aorta, with and without endothelium from sedentary and trained rats, submitted or not to stress, treated or not with nandrolone. None of the procedures altered the vascular reactivity to noradrenaline in denuded aorta. In intact aorta, stress and exercise produced vascular adaptive responses characterized by endothelium-dependent hyporeactivity to noradrenaline. These conditions in combination did not potentiate the vascular adaptive response. Exercise-induced vascular adaptive response was abolished by nandrolone. In contrast, the aortal reactivity to noradrenaline of sedentary rats and the vascular adaptive response to stress of sedentary and trained rats were not affected by nandrolone. Maximum response for 7-10 rats/group (g): sedentary 3.8 ± 0.2 vs trained 3.0 ± 0.2*; sedentary/stress 2.7 ± 0.2 vs trained/stress 3.1 ± 0.1*; sedentary/nandrolone 3.6 ± 0.1 vs trained/nandrolone 3.8 ± 0.1; sedentary/stress/nandrolone 3.2 ± 0.1 vs trained/stress/nandrolone 2.5 ± 0.1*; *P < 0.05 compared to its respective control. Stress and physical exercise determine similar vascular adaptive response involving distinct mechanisms as indicated by the observation that only the physical exercise-induced adaptive response was abolished by nandrolone.

We have previously demonstrated that acute third ventricle injections of both lead and cadmium prevent the dipsogenic response elicited by dehydration or by central injections of dipsogenic agents such as angiotensin II, carbachol and isoproterenol in rats. We have also shown that the antidipsogenic action of cadmium may be due, at least in part, to activation of thirst-inhibitory central serotonergic pathways. In the present paper we show that in Wistar male rats the antidipsogenic effect of both lead acetate (3.0 nmol/rat) and cadmium chloride (3.0 nmol/rat) may be partially dependent on the activation of brain opiatergic pathways since central injections of naloxone (82.5 nmol/rat), a non-selective opioid antagonist, blunt the thirst-inhibiting effect of these metals. One hundred and twenty minutes after the second third ventricle injections, dehydrated animals (14 h overnight) receiving saline + sodium acetate displayed a high water intake (7.90 ± 0.47 ml/100 g body weight) whereas animals receiving saline + lead acetate drank 3.24 ± 0.47 ml/100 g body weight. Animals receiving naloxone + lead acetate drank 6.94 ± 0.60 ml/100 g body weight. Animals receiving saline + saline drank 8.16 ± 0.66 ml/100 g body weight whilst animals receiving saline + cadmium chloride drank 1.63 ± 0.37 ml/100 g body weight. Animals receiving naloxone + cadmium chloride drank 8.01 ± 0.94 ml/100 g body weight. It is suggested that acute third ventricle injections of both lead and cadmium exert their antidipsogenic effect by activating thirst-inhibiting opioid pathways in the brain.

We have previously demonstrated that acute third ventricle injections of both Pb2+ and Cd2+ impair the dipsogenic response elicited by three different situations: dehydration and central cholinergic or angiotensinergic stimulation. ß-Adrenergic activation is part of the multifactorial integrated systems operating in drinking behavior control in the central nervous system. In the present study acute third ventricle injections of Pb2+ (3, 30 and 300 pmol/rat) or Cd2+ (0.3, 3 and 30 pmol/rat) blocked the dipsogenic response induced by third ventricle injections of isoproterenol (ISO; 160 nmol/rat) in a dose-dependent manner. Normohydrated animals receiving ISO + NaAc (sodium acetate) or saline (controls) displayed a high water intake after 120 min (ISO + saline = 5.78 ± 0.54 ml/100 g; ISO + NaAc = 6.00 ± 0.6 ml/100 g). After the same period, animals receiving ISO but pretreated with PbAc at the highest dose employed (300 pmol/rat) drank 0.78 ± 0.23 ml/100 g while those receiving ISO and pretreated with the highest dose of CdCl2 (30 pmol/rat) presented a water intake of 0.7 ± 0.30 ml/100 g. Third ventricle injections of CdCl2 (3 nmol/rat) or PbAc (3 nmol/rat) did not modify food intake in rats deprived of food for 24 h. Thus, general central nervous system depression explaining the antidipsogenic action of the metals can be safely excluded. It is concluded that both Pb2+ and Cd2+ inhibit water intake induced by central ß-adrenergic stimulation