Chitosan/Gelatin Scaffolds Loaded with Jatropha mollissima Extract as Potential Skin Tissue Engineering Materials.

This work aimed to develop chitosan/gelatin scaffolds loaded with ethanolic extract of Jatropha mollissima (EEJM) to evaluate the influence of its content on the properties of these structures. The scaffolds were prepared by freeze-drying, with different EEJM contents (0-10% (w/w)) and crosslinked with genipin (0.5% (w/w)). The EEJM were characterized through High Performance Liquid Chromatography coupled to a Diode Array Detector (HPLC-DAD), and the determination of three secondary metabolites contents was accomplished. The physical, chemical and biological properties of the scaffolds were investigated. From the HPLC-DAD, six main substances were evidenced, and from the quantification of the total concentration, the condensed tannins were the highest (431.68 ± 33.43 mg·g-1). Spectroscopy showed good mixing between the scaffolds' components. Adding and increasing the EEJM content did not significantly influence the properties of swelling and porosity, but did affect the biodegradation and average pore size. The enzymatic biodegradation test showed a maximum weight loss of 42.89 within 28 days and reinforced the efficiency of genipin in crosslinking chitosan-based materials. The addition of the extract promoted the average pore sizes at a range of 138.44-227.67 µm, which is compatible with those reported for skin regeneration. All of the scaffolds proved to be biocompatible for L929 cells, supporting their potential application as skin tissue engineering materials.

Development of Gelatin/Misoprostol Compounds for Use in Pregnancy Failures.

Early abortion is one of the most common complications during pregnancy. However, the frequent handling of the genital region, more precisely the vagina, which causes discomfort to patients in this abortion process due to the frequency of drug insertion, as four pills are inserted every six hours, has led to the search for alternatives to alleviate the suffering caused by this practice in patients who are already in a shaken emotional state. Hence, this work aimed to develop composites of gelatin and misoprostol, using a conventional single-dose drug delivery system. These composites were prepared by freeze/lyophilization technique, by dissolving the gelatin in distilled water, with a concentration of 2.5% (w/v), and misoprostol was incorporated into the gelatin solution at the therapeutic concentration (800 mcg). They were subsequently molded, frozen and lyophilized. The samples of the composites were then crosslinked with sodium tripolyphosphate (TPP) 1% (v/v) with respect to the gelatin mass for 5 min. The characterization techniques used were: Optical Microscopy (OM), Fourier Transformed Infrared Spectroscopy (FTIR), Thermogravimetry (TG), Swelling, Biodegradation and Cytotoxicity. In OM it was observed that the addition of the drug improved the cylindrical appearance of the compounds, in comparison with the sample that was composed of only gelatin. There was a reduction in the degree of swelling with the addition of the drug and crosslinking. The cytotoxicity test indicated the biocompatibility of the material. Based on the results obtained in these tests, the composites have therapeutic potential for uterine emptying in pregnancy failures, especially in the first trimester.

Biocompatible Sulphonated PEEK Spheres: Influence of Processing Conditions on Morphology and Swelling Behavior.

This work aimed to develop and evaluate the influence of processing variables on the morphology and swelling of sulfonated poly(ether ether ketone) (SPEEK) spheres for possible applications as a biomaterial. We used the drip method to obtain spheres with the polymer starting solutions SPEEK-6 (w/v: 6%) and SPEEK-10 (w/v: 10%), drip rates (20 and 30 mL/h), and drip heights (5 and 10 cm) in experimental planning. The samples were characterized by Fourier-transform infrared spectroscopy (FTIR), optical microscopy (OM), the absorption capacity of phosphate-buffered saline (PBS) by swelling (%), and statistical analysis of data through Design of Experiments (DOE). The obtained results evidenced that the processing variables influenced the morphology and swelling. Spheres with a bigger concentration of the polymer solution presented a greater degree of sulfonation (DS). We verified that the diameter of the spheres was directly related to the variable height and the sphericity was associated with the speed and viscosity of the solution. Bigger and more pores in a greater amount were observed in the spheres with a greater DS, influencing the behavior of the swelling in PBS. The better variable combinations with a high DS, regular sphericity, a smaller diameter, and greater swelling were the samples S2-10-20-5 e S10-10-20-5. The cytotoxicity indicated that the best samples obtained in the experimental planning (S2-10-20-5 and S10-10-20-5) were not toxic. In that regard, the evaluated spheres presented cell viability and swelling capacity, suggesting their possible applications as biomaterials.

Chitosan-Based Biomaterial, Calcium Hydroxide and Chlorhexidine for Potential Use as Intracanal Medication.

The objective of this study was to develop a chitosan-based biomaterial with calcium hydroxide and 2% chlorhexidine for intracanal treatment application and, consequently, to diminish the number of microorganisms in the root canal system. The chitosan solution was prepared by dissolving it in 2% and 4% acetic acid (v/v) for 1 h at room temperature (25 °C) with magnetic agitation (430 rpm). Calcium hydroxide was obtained in two stages: the first was the synthesis of the calcium oxide-CaO, and the second was that of the calcium hydroxide-Ca(OH)2. The samples were developed using different concentrations of chitosan, calcium hydroxide, and chlorhexidine 2%. They were codified as Ca(OH)2 + Q2% (M1), Ca(OH)2 + Q4% (M2), Ca(OH)2 + Q2% + CLX (M3), Ca(OH)2 + Q4% + CLX (M4), Ca(OH)2 + Q2% + PEG (M5), and Ca(OH)2 + Q4% + PEG (M6). They were characterized through Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), and rheological measurement, and the antimicrobial activity was evaluated in vitro. Characteristic absorption bands of the source materials used in this research were observed in the FTIR spectra. The X-ray diffraction technique indicated that the material has a semi-crystalline structure and that the presence of calcium hydroxide made the biomaterial more crystalline. The viscosity measurement showed a pseudoplastic behavior of the studied samples. The microbiologic analysis was positive for all samples tested, with bigger inhibition zones for the samples M3 and M4. As a result, we conclude that the formulation developed based on chitosan is promising and has potential to be an intracanal medication.

Chitosan Woven Meshes: Influence of Threads Configuration on Mechanical, Morphological, and Physiological Properties.

This study aimed to develop meshes from the weaving of mono- and multifilament wet-spun chitosan (CS), for possible biomedical applications. In the wet-spinning process, CS solution (4% w/v) was extruded in a coagulation bath containing 70% sodium hydroxide solution (0.5 M), and 30% methanol was used. The multifilament thread was prepared by twisted of two and three monofilaments. CS threads obtained were characterized by tensile tests and scanning electron microscopy (SEM). Moreover, it was verified from the morphological tests that threads preserve the characteristics of the individual filaments and present typical "skin-core" microstructure obtained by wet spinning. CS woven meshes obtained were evaluated by optical microscopy (OM), tensile test, swelling degree, and in vitro enzymatic biodegradation. Mechanical properties, biodegradation rate, and amount of fluid absorbed of CS woven meshes were influenced by thread configuration. Hydrated CS meshes showed a larger elastic zone than the dry state. Therefore, CS woven meshes were obtained with modular properties from thread configuration used in weaving, suggesting potential applications in the biomedical field, like dressings, controlled drug delivery systems, or mechanical support.

Esferas de quitosana/D. ambrosioides (mastruz) para aplicação como biomaterial / Chitosan/D. ambrosioides (mastruz) spheres to be applied as a biomaterial

Objetivo: Desenvolver esferas de quitosana/D. ambrosioides (mastruz) para aplicação como biomaterial. Material e Métodos: Para obtenção das esferas de quitosana e quitosana com extrato alcoólico bruto do mastruz (EAB) utilizou-se a técnica de GeleificaçãoIonotrópica. Foram formados quatro grupos: QO- quitosana; Q5; Q10 e Q20, quitosana com 5%, 10% e 20% de EAB, respectivamente. Foram caracterizadas por Microscopia Óptica (MO); Citotoxicidade e Biodegradação. Resultados: NoMO, observou-se esferas bem delimitadas e mais escuras, à medida que o percentual do EAB aumentou. Todos os grupos foram não citotóxicos. Na presença de lisozima, observou-se perda de massa, já na solução tampão fosfato salina (PBS) constatou-se ganho de massa. Conclusão: Conclui-se que as esferas apresentaram potencial para utilização como biomaterial.

Objective: This worked aimed to develop chitosan/D. ambrosioides (mastruz) spheres to be applied as a biomaterial. Material and Methods: To obtain the chitosan spheres and the chitosan with crude ethanolic extract of mastruz (CEE) the Ionotropic gelation technique was used. Four groups were formed: QO- Chitosan; Q5; Q10 and Q20, Chitosan with 5%, 10% and 20% of CEE, respectively. Were characterized by Optic Microscopy (OM); Cytotoxicity and Biodegradation.Results: InOM, well delimited and darker spheres were observed, as the CEE percentage increased. All groups were noncytotoxic. In the presence of lysozyme, mass loss was observed, as for in solution Phosphate Buffered Saline (PBS) the mass gain was found. Conclusion: It can be concluded that the spheres presented potential for use as a biomaterial.

Infecção experimental por Trypanosoma vivax em ovinos / Experimental infection by Trypanosoma vivax in sheep

O presente estudo teve por objetivo avaliar as alterações clínicas, hematológicas e patológicas em ovinos infectados experimentalmente com Trypanosoma vivax, utilizando-se um isolado proveniente de bovinos infectados naturalmente no município de Catolé do Rocha, Paraíba. Quatro ovinos da raça Santa Inês foram infectados por via intravenosa com 1ml de sangue contendo 1,85x10(5) tripomastigotas de T. vivax e outros quatro ovinos foram destinados ao grupo controle. A parasitemia e a temperatura foram determinadas diariamente durante 30 dias após a infecção (dpi) e quinzenalmente dos 31 aos 90 dias. A cada 15 dias os animais foram pesados e realizados coletas de sangue para hemograma. Um ovino morreu aos 75 dpi, os demais animais do grupo infectado e do grupo controle foram sacrificados 90 dias após o início do experimento. T. vivax foi evidenciado a partir do 4° dpi em todos os ovinos infectados. A parasitemia foi constante até os 15 dias e irregular entre os 16 e 30 dias. Após o 30° dia não foram observados parasitas no sangue. Foi observada correlação linear positiva entre temperatura retal e parasitemia [Y=0,027x + 38,515; R²=0,9444 (P<0,05)]. Diferença significativa do peso entre os grupos infectado e controle foi verificada a partir do 30° ao 90° dpi. Do 30° ao 90° os animais apresentaram anemia e leucopenia. As lesões macroscópicas encontradas na necropsia foram palidez da carcaça, aumento generalizado dos linfonodos e do baço, e discreta quantidade de líquido nas cavidades peritoneal e pericárdica. Histologicamente, em todos os animais infectados foi observada miocardite multifocal mononuclear. Concluiu-se que o isolado é patogênico para ovinos. Sugere-se que a região semi-árida onde ocorreu o surto, não é endêmica para a tripanossomíase e a doença pode ocorrer se o parasita for introduzido na presença de vetores.