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1.
Life Sci ; 242: 117185, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31862453

RESUMO

Colorectal cancer (CRC) is a multifactorial syndrome that drives to uncontrollable cell division, genetic alterations, and functional alteration. In the present work, we evaluated the immunomodulatory properties of P-mapa, a compound extracted from Aspergillus oryzae fungus, versus Fluorouracil (5-FU) treatment in chemically induced CRC. CRC was induced by DMH in F344 rats. Animals of treated groups receive weekly 15 mg/Kg of 5-FU or 5 mg/Kg of P-mapa, over 10 weeks. Tissues were stained for aberrant crypt foci (ACF) counting and histopathology evaluation, immunostained for TLR4 pathways and quantified for TNFα Cytokine assay. DMH was efficient to induce hyperplastic lesions and ACF. Both treatments reduced significantly ACF formation and tumor aggressiveness. Immunohistochemistry for TLR4 signaling reveals that both treatments had no effect over the TLR4-NFκB signaling pathway. On the other hand, both succeed in increase interferon signaling, with activation of the TRIF-IRF3 pathway and consequently inducing IFNγ synthesis. The present results show the immunomodulatory properties of P-mapa in chemically induced CRC model. P-mapa induced a significant increase in Type-I IFNs synthesis and subsequently immune cell recruitment, resulting in an increase of IFNγ concentration in colorectal mucosa and its inhibitory effects over tumoral growth. In this scenario, P-mapa showed an interesting antitumoral effect by inhibiting tumor growth.


Assuntos
Antineoplásicos/uso terapêutico , Neoplasias do Colo/tratamento farmacológico , Fatores Imunológicos/uso terapêutico , Ácidos Linoleicos/uso terapêutico , Ácidos Oleicos/uso terapêutico , Transdução de Sinais/efeitos dos fármacos , Receptor 4 Toll-Like/metabolismo , Focos de Criptas Aberrantes/patologia , Animais , Biopolímeros/uso terapêutico , Neoplasias do Colo/metabolismo , Neoplasias do Colo/patologia , Ensaio de Imunoadsorção Enzimática , Fluoruracila/uso terapêutico , Masculino , Ratos , Ratos Endogâmicos F344 , Fator de Necrose Tumoral alfa/metabolismo
2.
Rev Col Bras Cir ; 46(5): e20192260, 2019.
Artigo em Português, Inglês | MEDLINE | ID: mdl-31859723

RESUMO

OBJECTIVE: to evaluate the use of a bacterial cellulose biopolymer film and gel dressing in the treatment of patients with ischemic wounds submitted to lower limb revascularization. METHODS: we conducted a randomized clinical trial in the Angiology and Vascular Surgery outpatient clinic of the Clinics Hospital of the Federal University of Pernambuco, between January 2017 and December 2018. We followed 24 patients after lower limb revascularization, divided into two groups: Experimental, treated with bacterial cellulose biopolymer film and gel, and Control, treated with essential fatty acids. Patients attended weekly appointments to change dressings and had their wound healing processes evaluated over a period of 90 days. RESULTS: the reduction of the ischemic wounds' areas after 30 days was 4.3cm2 (55%) on average for the experimental group, and the 5.5cm2 (48.5%) for the control group (p>0.05). The complete healing rate at 90 days was 34.8%, 50% in the experimental group and 18.2% in the control group (p=0.053). CONCLUSION: the bacterial cellulose biopolymer film associated with gel can be used as a dressing in the treatment of ischemic wounds of patients undergoing revascularization of the lower limbs.


Assuntos
Bandagens , Biopolímeros/uso terapêutico , Celulose/uso terapêutico , Isquemia/complicações , Isquemia/terapia , Extremidade Inferior/patologia , Cicatrização/efeitos dos fármacos , Idoso , Idoso de 80 Anos ou mais , Angioplastia , Feminino , Géis/uso terapêutico , Humanos , Isquemia/patologia , Extremidade Inferior/irrigação sanguínea , Masculino , Pessoa de Meia-Idade , Fatores de Tempo , Resultado do Tratamento
3.
Biomacromolecules ; 20(12): 4272-4298, 2019 12 09.
Artigo em Inglês | MEDLINE | ID: mdl-31738532

RESUMO

Proteins, nucleic acids, lipid vesicles, and carbohydrates are the major classes of biomacromolecules that function to sustain life. Biology also uses post-translation modification to increase the diversity and functionality of these materials, which has inspired attaching various other types of polymers to biomacromolecules. These polymers can be naturally (carbohydrates and biomimetic polymers) or synthetically derived and have unique properties with tunable architectures. Polymers are either grafted-to or grown-from the biomacromolecule's surface, and characteristics including polymer molar mass, grafting density, and degree of branching can be controlled by changing reaction stoichiometries. The resultant conjugated products display a chimerism of properties such as polymer-induced enhancement in stability with maintained bioactivity, and while polymers are most often conjugated to proteins, they are starting to be attached to nucleic acids and lipid membranes (cells) as well. The fundamental studies with protein-polymer conjugates have improved our synthetic approaches, characterization techniques, and understanding of structure-function relationships that will lay the groundwork for creating new conjugated biomacromolecular products which could lead to breakthroughs in genetic and tissue engineering.


Assuntos
Materiais Biomiméticos , Biopolímeros , Engenharia Genética , Polimerização , Engenharia Tecidual , Materiais Biomiméticos/síntese química , Materiais Biomiméticos/química , Materiais Biomiméticos/uso terapêutico , Biopolímeros/química , Biopolímeros/uso terapêutico , Membrana Celular/metabolismo , Humanos , Relação Estrutura-Atividade
4.
J Biomed Mater Res A ; 107(12): 2736-2755, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31408265

RESUMO

Cryogels are a subset of hydrogels synthesized under sub-zero temperatures: initially solvents undergo active freezing, which causes crystal formation, which is then followed by active melting to create interconnected supermacropores. Cryogels possess several attributes suited for their use as bioscaffolds, including physical resilience, bio-adaptability, and a macroporous architecture. Furthermore, their structure facilitates cellular migration, tissue-ingrowth, and diffusion of solutes, including nano- and micro-particle trafficking, into its supermacropores. Currently, subsets of cryogels made from both natural biopolymers such as gelatin, collagen, laminin, chitosan, silk fibroin, and agarose and/or synthetic biopolymers such as hydroxyethyl methacrylate, poly-vinyl alcohol, and poly(ethylene glycol) have been employed as 3D bioscaffolds. These cryogels have been used for different applications such as cartilage, bone, muscle, nerve, cardiovascular, and lung regeneration. Cryogels have also been used in wound healing, stem cell therapy, and diabetes cellular therapy. In this review, we summarize the synthesis protocol and properties of cryogels, evaluation techniques as well as current in vitro and in vivo cryogel applications. A discussion of the potential benefit of cryogels for future research and their application are also presented.


Assuntos
Materiais Biocompatíveis/química , Criogéis/química , Polímeros/química , Tecidos Suporte/química , Animais , Materiais Biocompatíveis/uso terapêutico , Biopolímeros/química , Biopolímeros/uso terapêutico , Criogéis/uso terapêutico , Humanos , Polímeros/uso terapêutico , Porosidade , Medicina Regenerativa/métodos , Engenharia Tecidual/métodos
5.
Nat Commun ; 10(1): 2060, 2019 05 14.
Artigo em Inglês | MEDLINE | ID: mdl-31089131

RESUMO

Uncontrollable bleeding is a major problem in surgical procedures and after major trauma. Existing hemostatic agents poorly control hemorrhaging from traumatic arterial and cardiac wounds because of their weak adhesion to wet and mobile tissues. Here we design a photo-reactive adhesive that mimics the extracellular matrix (ECM) composition. This biomacromolecule-based matrix hydrogel can undergo rapid gelling and fixation to adhere and seal bleeding arteries and cardiac walls after UV light irradiation. These repairs can withstand up to 290 mm Hg blood pressure, significantly higher than blood pressures in most clinical settings (systolic BP 60-160 mm Hg). Most importantly, the hydrogel can stop high-pressure bleeding from pig carotid arteries with 4~ 5 mm-long incision wounds and from pig hearts with 6 mm diameter cardiac penetration holes. Treated pigs survived after hemostatic treatments with this hydrogel, which is well-tolerated and appears to offer significant clinical advantage as a traumatic wound sealant.


Assuntos
Adesivos/uso terapêutico , Biopolímeros/uso terapêutico , Hemorragia/terapia , Hemostáticos/uso terapêutico , Hidrogéis/uso terapêutico , Adesivos/química , Adesivos/efeitos da radiação , Animais , Artérias/lesões , Artérias/cirurgia , Biopolímeros/química , Biopolímeros/efeitos da radiação , Linhagem Celular , Vasos Coronários/lesões , Vasos Coronários/cirurgia , Modelos Animais de Doenças , Matriz Extracelular/química , Hemorragia/etiologia , Hemostáticos/química , Hemostáticos/efeitos da radiação , Humanos , Hidrogéis/química , Hidrogéis/efeitos da radiação , Masculino , Polimerização/efeitos da radiação , Ferida Cirúrgica/complicações , Resultado do Tratamento , Raios Ultravioleta
6.
Medicina (Kaunas) ; 55(5)2019 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-31108965

RESUMO

Background and objectives: Cancer is the second leading cause of death globally, an alarming but expected increase. In comparison to other types of cancer, malignant bone tumors are unusual and their treatment is a real challenge. This paper's main purpose is the study of the potential application of composite scaffolds based on biopolymers and calcium phosphates with the inclusion of magnetic nanoparticles in combination therapy for malignant bone tumors. Materials and Methods: The first step was to investigate if X-rays could modify the scaffolds' properties. In vitro degradation of the scaffolds exposed to X-rays was analyzed, as well as their interaction with phosphate buffer solutions and cells. The second step was to load an anti-tumoral drug (doxorubicin) and to study in vitro drug release and its interaction with cells. The chemical structure of the scaffolds and their morphology were studied. Results: Analyses showed that X-ray irradiation did not influence the scaffolds' features. Doxorubicin release was gradual and its interaction with cells showed cytotoxic effects on cells after 72 h of direct contact. Conclusions: The obtained scaffolds could be considered in further studies regarding combination therapy for malignant bone tumors.


Assuntos
Biopolímeros/uso terapêutico , Neoplasias Ósseas/terapia , Fosfatos de Cálcio/uso terapêutico , Quimiorradioterapia/métodos , Tecidos Suporte , Biopolímeros/administração & dosagem , Fosfatos de Cálcio/administração & dosagem , Quimiorradioterapia/normas , Humanos , Nanopartículas de Magnetita/administração & dosagem , Nanopartículas de Magnetita/uso terapêutico
7.
Artigo em Inglês | MEDLINE | ID: mdl-30666829

RESUMO

Sugar-based biopolymers have been recognized as attractive materials to develop macromolecule- and nanoparticle-based cancer imaging and therapy. However, traditional biopolymer-based imaging approaches rely on the use of synthetic or isotopic labeling, and because of it, clinical translation often is hindered. Recently, a novel magnetic resonance imaging (MRI) technology, chemical exchange saturation transfer (CEST), has emerged, which allows the exploitation of sugar-based biopolymers as MRI agents by their hydroxyl protons-rich nature. In the study, we reviewed recent studies on the topic of CEST MRI detection of sugar-based biopolymers. The CEST MRI property of each biopolymer was briefly introduced, followed by the pre-clinical and clinical applications. The findings of these preliminary studies imply the enormous potential of CEST detectable sugar-based biopolymers in developing highly sensitive and translatable molecular imaging agents and constructing image-guided biopolymer-based drug delivery systems. This article is categorized under: Diagnostic Tools > in vivo Nanodiagnostics and Imaging Therapeutic Approaches and Drug Discovery > Emerging Technologies.


Assuntos
Biopolímeros , Meios de Contraste , Imagem por Ressonância Magnética , Imagem Molecular , Açúcares , Biopolímeros/química , Biopolímeros/uso terapêutico , Meios de Contraste/química , Meios de Contraste/uso terapêutico , Humanos , Açúcares/química , Açúcares/uso terapêutico
8.
Rev. Col. Bras. Cir ; 46(5): e20192260, 2019. tab, graf
Artigo em Português | LILACS | ID: biblio-1057172

RESUMO

RESUMO Objetivo: avaliar o uso do curativo de filme e gel de biopolímero de celulose bacteriana no tratamento de pacientes com feridas isquêmicas submetidos à revascularização dos membros inferiores. Métodos: ensaio clínico randomizado realizado no ambulatório de Angiologia e Cirurgia Vascular do Hospital das Clínicas da Universidade Federal de Pernambuco, entre janeiro de 2017 e dezembro de 2018. Foram acompanhados 24 pacientes após revascularização de membros inferiores, divididos em dois grupos: Experimental, tratado com filme e gel de biopolímero de celulose bacteriana, e Controle, tratado com ácidos graxos essenciais. Os pacientes foram acompanhados em consultas semanais para troca dos curativos e o processo de cicatrização das feridas foi avaliado em um período de 90 dias. Resultados: a redução da área das feridas isquêmicas no período de 30 dias foi de 4,3cm2 (55%), em média, para o grupo experimental, e de 5,5cm2 (48,5%) para o grupo controle (p>0,05). A taxa de cicatrização completa, em 90 dias, foi de 34,8%, sendo 50% no grupo experimental e 18,2% no grupo controle (p=0,053). Conclusão: o filme de biopolímero de celulose bacteriana associada a gel pode ser utilizado como curativo no tratamento de feridas isquêmicas de pacientes submetidos à revascularização de membros inferiores


ABSTRACT Objective: to evaluate the use of a bacterial cellulose biopolymer film and gel dressing in the treatment of patients with ischemic wounds submitted to lower limb revascularization. Methods: we conducted a randomized clinical trial in the Angiology and Vascular Surgery outpatient clinic of the Clinics Hospital of the Federal University of Pernambuco, between January 2017 and December 2018. We followed 24 patients after lower limb revascularization, divided into two groups: Experimental, treated with bacterial cellulose biopolymer film and gel, and Control, treated with essential fatty acids. Patients attended weekly appointments to change dressings and had their wound healing processes evaluated over a period of 90 days. Results: the reduction of the ischemic wounds' areas after 30 days was 4.3cm2 (55%) on average for the experimental group, and the 5.5cm2 (48.5%) for the control group (p>0.05). The complete healing rate at 90 days was 34.8%, 50% in the experimental group and 18.2% in the control group (p=0.053). Conclusion: the bacterial cellulose biopolymer film associated with gel can be used as a dressing in the treatment of ischemic wounds of patients undergoing revascularization of the lower limbs.


Assuntos
Humanos , Masculino , Feminino , Idoso , Idoso de 80 Anos ou mais , Bandagens , Cicatrização/efeitos dos fármacos , Biopolímeros/uso terapêutico , Celulose/uso terapêutico , Extremidade Inferior/patologia , Isquemia/complicações , Isquemia/terapia , Fatores de Tempo , Resultado do Tratamento , Angioplastia , Extremidade Inferior/irrigação sanguínea , Géis/uso terapêutico , Isquemia/patologia , Pessoa de Meia-Idade
9.
Prog Neurobiol ; 171: 125-150, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30077776

RESUMO

Injuries to the peripheral nervous system (PNS) cause neuropathies that lead to weakness and paralysis, poor or absent sensation, unpleasant and painful neuropathies, and impaired autonomic function. In this regard, implanted artificial nerve guidance conduits (NGCs) used to bridge an injured site may provide appropriate biochemical and biophysical guidance cues required to stimulate regeneration across a nerve gap and restore the function of PNS. Advanced conduit design and fabrication techniques have made it possible to fabricate autograft-like structures in the NGCs with incredible precision. To this end, strategies involving the use of biopolymers, cells, growth factors, and physical stimuli have been developed over the past decades and have led to the development of varying NGCs, from simple hollow tubes to complex conduits that incorporate one or more guidance cues. This paper briefly reviews the recent progress in the development of these NGCs for nerve regeneration, focusing on the design and fabrication of NGCs, as well as the influence of biopolymers, cells, growth factors, and physical stimuli. The advanced techniques used to fabricate NGCs that incorporate cells/growth factors are also discussed, along with their merits and flaws. Key issues and challenges with regard to the development of NGCs have been identified and discussed, and recommendations for future research have been included.


Assuntos
Regeneração Tecidual Guiada/métodos , Regeneração Nervosa/fisiologia , Doenças do Sistema Nervoso Periférico/terapia , Animais , Biopolímeros/uso terapêutico , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/uso terapêutico , Estimulação Física , Projetos de Pesquisa
10.
Mol Biol Rep ; 45(6): 2857-2867, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30094529

RESUMO

Wound is a growing healthcare challenge affecting several million worldwide. Lifestyle disorders such as diabetes increases the risk of wound complications. Effective management of wound is often difficult due to the complexity in the healing process. Addition to the conventional wound care practices, the bioactive polymers are gaining increased importance in wound care. Biopolymers are naturally occurring biomolecules synthesized by microbes, plants and animals with highest degree of biocompatibility. The bioactive properties such as antimicrobial, immune-modulatory, cell proliferative and angiogenic of the polymers create a microenvironment favorable for the healing process. The versatile properties of the biopolymers such as cellulose, alginate, hyaluronic acid, collagen, chitosan etc have been exploited in the current wound care market. With the technological advances in material science, regenerative medicine, nanotechnology, and bioengineering; the functional and structural characteristics of biopolymers can be improved to suit the current wound care demands such as tissue repair, restoration of lost tissue integrity and scarless healing. In this review we highlight on the sources, mechanism of action and bioengineering approaches adapted for commercial exploitation.


Assuntos
Biopolímeros/uso terapêutico , Engenharia Tecidual/métodos , Cicatrização/efeitos dos fármacos , Alginatos/uso terapêutico , Animais , Celulose/uso terapêutico , Quitosana/uso terapêutico , Colágeno/uso terapêutico , Humanos , Ácido Hialurônico/uso terapêutico , Medicina Regenerativa/métodos , Pele/metabolismo , Transplante de Pele/métodos
11.
Rev Col Bras Cir ; 45(4): e1837, 2018 Aug 06.
Artigo em Português, Inglês | MEDLINE | ID: mdl-30088524

RESUMO

OBJECTIVE: to evaluate, through Doppler flowmetry, venography, histology and clinical evolution, the use of sugarcane biopolymer (BP) tubular grafts in the reconstruction of femoral veins in dogs. METHODS: we submitted eight adult dogs to femoral vein reconstruction, on the left with BP tubular graft and on the right with autologous vein. In the postoperative period, the animals underwent clinical evaluation and femoral vein Doppler flowmetry. After 360 days, we reoperated the dogs and submitted them to femoral vein phlebography with iodinated contrast. We removed the segments of the femoral veins containing the grafts and sent them for histopathological evaluation. RESULTS: the dogs did not present hemorrhage, hematoma, surgical wound infection or operated limb edema. One animal had superficial venous dilatation in the left inguinal region. Phlebography performed 360 days after the first surgery showed that three (37.5%) BP grafts and seven (87.5%) grafts from the control group (C) were patent. In the histopathological evaluation, we found an inflammatory reaction, with neutrophils and lymphocytes on the external surface of both groups. In the intimal layer of the grafts and in the outer layer in the two groups, we observed fibrosis. CONCLUSION: based on the results obtained with the experimental model used, BP presents potential to be used as a tubular graft for venous revascularization. However, new research must be performed to confirm its efficacy in the revascularization of medium and large diameter veins, which could allow its use in clinical practice.


Assuntos
Bioprótese , Implante de Prótese Vascular/métodos , Prótese Vascular , Veia Femoral/transplante , Enxerto Vascular/métodos , Animais , Biopolímeros/uso terapêutico , Implante de Prótese Vascular/instrumentação , Cães , Feminino , Veia Femoral/patologia , Fluxometria por Laser-Doppler , Masculino , Modelos Animais , Distribuição Aleatória , Procedimentos Cirúrgicos Reconstrutivos/métodos , Saccharum , Transplante Autólogo/métodos
13.
Adv Exp Med Biol ; 1059: 155-188, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29736573

RESUMO

Semi-interpenetrating polymer networks (semi-IPNs) and interpenetrating polymeric networks (IPNs) have emerged as innovative materials for biomedical and pharmaceutical applications. The interest in these structures is due to the possibility of combining the favorable properties of each polymeric component of the IPNs or semi-IPNs leading to a new system with properties that often differ from those of the two single components. In this respect, polysaccharides represent an opportunity in this field, combining a general biocompatibility and a good availability. Moreover, the functional groups along the polymer chains allow chemical derivatization, widening the possibilities in semi-IPNs and IPNs building up. At the same time, materials based on proteins are often used in this field, due to their similarity to the materials present in the human body. All these overall properties allow tailoring new materials, thus designing desired properties and preparing new hydrogels useful in the biomedical field. In the present chapter, we chose to describe systems prepared starting from the most important and studied hydrogel-forming polysaccharides: alginate, hyaluronic acid, chitosan, dextran, gellan, and scleroglucan. Besides, systems based on proteins, such as gelatin, collagen, and elastin, are also described. With this chapter, we aim describing the routes already traveled in this field, depicting the state of the art and hoping to raise interest in designing new promising strategies useful in biomedical and pharmaceutical applications.


Assuntos
Materiais Biocompatíveis/química , Biopolímeros/química , Hidrogéis/química , Materiais Biocompatíveis/uso terapêutico , Fenômenos Biomecânicos , Biopolímeros/uso terapêutico , Configuração de Carboidratos , Físico-Química , Colágeno/química , Colágeno/uso terapêutico , Reagentes para Ligações Cruzadas/farmacologia , Desenho de Fármacos , Elastina/química , Elastina/uso terapêutico , Gelatina/química , Gelatina/uso terapêutico , Humanos , Hidrogéis/uso terapêutico , Concentração de Íons de Hidrogênio , Polissacarídeos/química , Polissacarídeos/uso terapêutico , Relação Estrutura-Atividade , Temperatura , Tecidos Suporte
14.
Mil Med ; 183(suppl_1): 433-444, 2018 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-29635619

RESUMO

Complex extremity wounds in Wounded Warriors can become contaminated with microbes, which may cause clinical outcomes resulting in amputation, morbidity, or even fatality. Local delivery of multiple or broad-spectrum antibiotics allows practicing clinicians treatment solutions that may inhibit biofilm formation. Propagation of vancomycin-resistant Staphylococcus aureus is also a growing concern. The development of vancomycin-resistant S. aureus has become a critical challenge in nosocomial infection prevention in the USA, but to date has seen little occurrence in osteomyelitis. As an alternative, locally delivered ciprofloxacin and rifampin were investigated in a preclinical model for the prevention of biofilm in complex extremity wounds with implanted fixation device. In vitro assays demonstrated ciprofloxacin and rifampin possess an additive effect against Gram-negative Pseudomonas aeruginosa and were actively eluted from a chitosan sponge based local delivery system. In an in vivo orthopedic hardware-associated polymicrobial model (S. aureus and Escherichia coli) the combination was able to achieve complete clearance of both bacterial strains. E. coli was detected in bone of untreated animals, but did not form biofilm on wires. Results reveal the clinical potential of antibiotic-loaded chitosan sponges to inhibit infection through tailored antibiotic selection at desired concentrations with efficacy towards biofilm inhibition.


Assuntos
Biopolímeros/farmacologia , Quitosana/farmacologia , Ciprofloxacino/administração & dosagem , Rifampina/administração & dosagem , Análise de Variância , Animais , Antibacterianos/administração & dosagem , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Infecções Bacterianas/tratamento farmacológico , Infecções Bacterianas/prevenção & controle , Biopolímeros/uso terapêutico , Quitosana/uso terapêutico , Cromatografia Líquida de Alta Pressão/métodos , Ciprofloxacino/uso terapêutico , Camundongos , Testes de Sensibilidade Microbiana/métodos , Rifampina/uso terapêutico , Staphylococcus aureus/efeitos dos fármacos
15.
Phytomedicine ; 38: 57-65, 2018 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-29425655

RESUMO

BACKGROUND: Millions of people in the world suffer from chronic wounds of different etiologies such as diabetic foot and leg ulcers, without solutions nowadays. Molecules obtained from plants offer an alternative to aid wound healing. Strong evidence about essential oils (EO) anti-inflammatory and antimicrobial properties is thoroughly described in literature and their chemical compositions are well characterized. More recently, EO effects in experimental wounds have begun to be analyzed. AIM: We aim to summarize the evidence of EO in experimental wounds, and the possibility of combining them with biopolymers commonly used in skin regeneration. METHODS: Electronic databases such as ScienceDirect, PubMed and Scopus were used to search scientific contributions until March 2017, using relevant keywords. In a first step, literature focusing on EO and/or mono- or sesqui-terpenoids effects in rodent wounds was identified and summarized. In all cases, chemical structures and EO composition were detailed, as well as references to in vitro activities previously determined, e.g. antibacterial, antioxidant or anti-inflammatory. In a second step, scientific literature devoted to combine EO and biopolymers with the focus set on wound healing innovations, was collected and analyzed. RESULTS: Treatments with EO from species of genders Lavandula, Croton, Blumea, Eucalyptus, Pinus, Cymbopogon, Eucalyptus, Cedrus, Abies, Rosmarinus, Origanum, Salvia and Plectranthus, have shown positive results in rodent wounds. All of these EO were mainly composed by monoterpenoids-thymol, 1,8-cineole, linalool-or monoterpenes, as limonene or pinenes. Experimental wounds in rodents have shown faster closure rate, better collagen deposition and/or enhanced fibroblasts proliferation. In blends with biopolymers, several EO combined with chitosan, alginate, gelatin or collagen, were processed to give active films or nanofibers, with antioxidant, anti-inflammatory or antimicrobial activities. Curiously, all of these works were carried out since 2010. CONCLUSIONS: There is significant evidence about the effectivity of EO as wound healers. The incorporation of EO into a polymer matrix that contributes to wound healing is still incipient. However, scientific based evidence of the EO incorporation in resorbable polymeric scaffolds was found and analyzed herein. In summary, EO-biopolymer dressings or scaffolds have become promising artifacts regarding wound treatments, especially in chronic wounds, where treating infection and inflammation are still important issues.


Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Biopolímeros/farmacologia , Óleos Voláteis/química , Óleos Voláteis/farmacologia , Cicatrização/efeitos dos fármacos , Alginatos/química , Animais , Biopolímeros/química , Biopolímeros/uso terapêutico , Colágeno/metabolismo , Pé Diabético/etiologia , Pé Diabético/terapia , Modelos Animais de Doenças , Ácido Glucurônico/química , Ácidos Hexurônicos/química , Humanos , Terpenos/análise , Terpenos/farmacologia
16.
Int J Biol Macromol ; 107(Pt A): 247-253, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28867232

RESUMO

Nowadays, fabrication of composite materials based on biopolymers is a rising field due to potential for bone repair and tissue engineering application. Blending of different biopolymers and incorporation of inorganic particles in the blend can lead to new materials with improved physicochemical properties and biocompatibility. In this work 3D porous structures called scaffolds based on chitosan, collagen and hyaluronic acid were obtained through the lyophilization process. Scaffolds were cross-linked by EDC/NHS. Infrared spectra for the materials were made, the percentage of swelling, scaffolds porosity and density, mechanical parameters, thermal stability were studied. Moreover, the scaffolds were used as matrixes for the calcium phosphate in situ precipitation. SEM images were taken and EDX analysis was carried out for calcium and phosphorous content determination in the scaffold. In addition, the adhesion and proliferation of human osteosarcoma SaOS-2 cells was examined on obtained scaffolds. The results showed that the properties of 3D composites cross-linked by EDC/NHS were altered after the addition of 1, 2 and 5% hyaluronic acid. Mechanical parameters, thermal stability and porosity of scaffolds were improved. Moreover, calcium and phosphorous were found in each kind of scaffold. SEM images showed that the precipitation was homogeneously carried in the whole volume of samples. Attachment of SaOS-2 cells to all modified materials was better compared to unmodified control and proliferation of these cells was markedly increased on scaffolds with precipitated calcium phosphate. Obtained materials can provide the support useful in tissue engineering and regenerative medicine.


Assuntos
Quitosana/química , Colágeno/química , Ácido Hialurônico/química , Engenharia Tecidual , Materiais Biocompatíveis/síntese química , Materiais Biocompatíveis/química , Materiais Biocompatíveis/uso terapêutico , Biopolímeros/química , Biopolímeros/uso terapêutico , Fosfatos de Cálcio/química , Quitosana/síntese química , Quitosana/uso terapêutico , Colágeno/síntese química , Colágeno/uso terapêutico , Humanos , Ácido Hialurônico/síntese química , Ácido Hialurônico/uso terapêutico , Tecidos Suporte/química
18.
Rev. Col. Bras. Cir ; 45(4): e1837, 2018. tab, graf
Artigo em Português | LILACS | ID: biblio-956572

RESUMO

RESUMO Objetivo: avaliar, através de dopplerfluxometria, de venografia, de histologia e de evolução clínica, o uso de enxertos tubulares de biopolímero de cana-de-açúcar (BP) na reconstrução de veias femorais em cães. Métodos: oito cães adultos foram submetidos à reconstrução de veia femoral, à esquerda com enxerto tubular de BP e à direita com veia autóloga. No período pós-operatório, os animais foram submetidos à avaliação clínica e dopplerfluxometria das veias femorais. Após 360 dias, os cães foram reoperados e submetidos à flebografia das veias femorais com contraste iodado. Os segmentos das veias femorais contendo os enxertos foram retirados e enviados para avaliação histopatológica. Resultados: os cães não apresentaram hemorragia, hematoma, infecção da ferida operatória ou edema dos membros operados. Um animal apresentou dilatação venosa superficial na região inguinal esquerda. A flebografia realizada 360 dias após a primeira cirurgia demonstrou que três (37,5%) enxertos de BP e sete (87,5%) do grupo controle (C) estavam pérvios. Na avaliação histopatológica foi encontrada uma reação inflamatória com neutrófilos e linfócitos na superfície externa de ambos os grupos. Na camada íntima de revestimento dos enxertos e na camada externa nos dois grupos, foi encontrada fibrose. Conclusão: com base nos resultados obtidos com o modelo experimental utilizado, conclui-se que a BP apresenta potencial para ser utilizado como enxerto tubular para revascularização venosa, porém novas pesquisas precisam ser realizadas para confirmar a sua eficácia na revascularização de veias de médio e grande calibre, o que poderia permitir o seu uso na prática clínica.


ABSTRACT Objective: to evaluate, through Doppler flowmetry, venography, histology and clinical evolution, the use of sugarcane biopolymer (BP) tubular grafts in the reconstruction of femoral veins in dogs. Methods: we submitted eight adult dogs to femoral vein reconstruction, on the left with BP tubular graft and on the right with autologous vein. In the postoperative period, the animals underwent clinical evaluation and femoral vein Doppler flowmetry. After 360 days, we reoperated the dogs and submitted them to femoral vein phlebography with iodinated contrast. We removed the segments of the femoral veins containing the grafts and sent them for histopathological evaluation. Results: the dogs did not present hemorrhage, hematoma, surgical wound infection or operated limb edema. One animal had superficial venous dilatation in the left inguinal region. Phlebography performed 360 days after the first surgery showed that three (37.5%) BP grafts and seven (87.5%) grafts from the control group (C) were patent. In the histopathological evaluation, we found an inflammatory reaction, with neutrophils and lymphocytes on the external surface of both groups. In the intimal layer of the grafts and in the outer layer in the two groups, we observed fibrosis. Conclusion: based on the results obtained with the experimental model used, BP presents potential to be used as a tubular graft for venous revascularization. However, new research must be performed to confirm its efficacy in the revascularization of medium and large diameter veins, which could allow its use in clinical practice.


Assuntos
Animais , Masculino , Feminino , Cães , Bioprótese , Prótese Vascular , Implante de Prótese Vascular/métodos , Veia Femoral/transplante , Enxerto Vascular/métodos , Transplante Autólogo/métodos , Biopolímeros/uso terapêutico , Distribuição Aleatória , Fluxometria por Laser-Doppler , Implante de Prótese Vascular/instrumentação , Procedimentos Cirúrgicos Reconstrutivos/métodos , Modelos Animais , Saccharum , Veia Femoral/patologia
19.
Molecules ; 22(11)2017 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-29144424

RESUMO

In an attempt to enhance chitosan biological activities, biopolymeric Schiff bases of chitosan and different salicylaldehydes and their palladium(II) and platinum(II) complexes were synthesized and tested. The chemical structures of these derivatives were characterized using ¹H-NMR, FTIR spectroscopy and XPRD. Thermal analysis was done through TGA/DTG-DTA. Electronic absorption spectra and surface morphologies were analyzed by SEM-EDAX. Chitosan and its derivatives were evaluated for their in vitro antimicrobial activity against two common bacterial and fungal plant pathogens Pseudomonas syringae pv. tomato and Fusarium graminearum, respectively, and for their antitumor activity against a human breast cancer cell line (MCF-7). It was found that, compared to the nonmodified chitosan, chitosan modified with Schiff bases and their complexes was highly toxic against the MCF-7 cell line and had antibacterial effects against P. syringea. However, the modified chitosan derivatives had less pronounced antifungal effects against F. graminearum compared to the nonmodified chitosan, suggesting different modes of action.


Assuntos
Aldeídos/química , Biopolímeros/química , Quitosana/química , Complexos de Coordenação/síntese química , Bases de Schiff/síntese química , Antibacterianos/síntese química , Antibacterianos/farmacologia , Antifúngicos/química , Antifúngicos/farmacologia , Antineoplásicos/química , Antineoplásicos/farmacologia , Biopolímeros/uso terapêutico , Sobrevivência Celular/efeitos dos fármacos , Complexos de Coordenação/farmacologia , Humanos , Células MCF-7 , Testes de Sensibilidade Microbiana , Paládio/química , Platina/química , Polimerização , Bases de Schiff/farmacologia
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