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1.
Braz Oral Res ; 33: e114, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31800865

RESUMO

This in vitro study aimed to evaluate the effect of different toothpastes on dental enamel subjected to an erosive cycle with and without exposure to cigarette smoke. Bovine enamel specimens were randomly allocated into 12 groups (n = 12). For the in vitro simulation of smoking, half the groups underwent an exposure cycle of 20 cigarettes per day for 5 days. Subsequently, all groups were subjected to a 5-day erosion cycle intercalating demineralization (1 min; 1% citric acid; pH = 3.5) and treatment with toothpaste slurries (2 min) of NaF, SnF2, F/Sn/Chitosan, F/CaSiO3/Na3PO4, and F/bioactive glass. The control group was immersed in distilled water. Surface microhardness (SMH) was measured initially, after exposure to smoke, and after the erosive cycle, and %SMH was calculated. At the end of the experimental cycle, surface roughness, profilometry, and atomic force microscopy (AFM) were performed. SMH increased after exposure to cigarette smoke (p < 0.05). After the erosive cycle, there were no differences between the presence and absence of cigarette smoke exposure in SMH and roughness (p > 0.05). Besides increasing enamel SMH, cigarette smoke did not prevent enamel loss after the erosion cycle (p < 0.05). In profilometry, roughness and surface loss had the lowest values in the groups treated with SnF2 and F/Sn/Chitosan (p < 0.05). AFM showed lower mineral loss with F/CaSiO3/Na3PO4 and F/Sn/Chitosan. For all groups, except F/CaSiO3/Na3PO4, cigarette smoke resulted in higher enamel wear. F/Sn/Chitosan showed the best results against erosion.


Assuntos
Fumar Cigarros/efeitos adversos , Esmalte Dentário/efeitos dos fármacos , Erosão Dentária/etiologia , Erosão Dentária/prevenção & controle , Cremes Dentais/uso terapêutico , Animais , Compostos de Cálcio/uso terapêutico , Cariostáticos/uso terapêutico , Bovinos , Quitosana/uso terapêutico , Testes de Dureza , Humanos , Microscopia de Força Atômica , Valores de Referência , Reprodutibilidade dos Testes , Saliva/química , Silicatos/uso terapêutico , Propriedades de Superfície/efeitos dos fármacos , Fatores de Tempo , Fluoretos de Estanho/uso terapêutico , Desmineralização do Dente/induzido quimicamente , Desmineralização do Dente/prevenção & controle , Água/química
2.
Pesqui. vet. bras ; 39(10): 837-842, Oct. 2019. ilus
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1056907

RESUMO

Chitosan has been successfully used as a biomaterial with several purposes in many species. In this study, chitosan membranes were produced with six different types of materials, and their behavior were evaluated upon implantation in the subcutaneous tissue of the flank of twelve healthy horses. We assessed chitosan membranes obtained from commercial chitosan, impregnated or not with silver nanoparticles, sterilized with ethylene oxide (CCEO, n=3; CCSNEO, n=3) or by ultraviolet radiation (CCUR, n=3; CCSNUR, n=3), and chitosan membranes obtained from squid gladius, sterilized with ethylene oxide (SCEO, n=6) or by ultraviolet radiation (SCUR, n=6). The same animals were randomly used in two experimental groups, with a minimum interval of 60 days between procedures, respecting the fact of only one flank side, left or right, be under evaluation by experimental period. After preparation of the membranes and implantation in the flank subcutaneous tissue of the horses, macroscopic and ultrasonographic evaluations of the implant regions were performed, as well as physical examination, blood count and fibrinogen measurement. No clinical or laboratory abnormalities were observed. All animals that received commercial chitosan membranes, regardless of the preparation technique, showed rejection to the biomaterials, considering that 100% of the surgical wounds presented dehiscence of suture and expulsion of the implants. The animals that received squid gladius chitosan membranes showed success in the treatment, with healing by primary intention of the surgical wound. We conclude that squid gladius chitosan membranes are biocompatible and biodegradable when implanted in the subcutaneous tissue of the flank of healthy horses.(AU)


A quitosana tem sido utilizada, com sucesso, como biomaterial para diversas espécies e finalidades. Neste estudo foi avaliada a confecção de membranas de quitosana, produzidas a partir de seis tipos de materiais diferentes e foi estudado seu comportamento quando implantadas no tecido subcutâneo do flanco de doze equinos sadios. Foram avaliadas membranas de quitosana obtidas de quitosana comercial, impregnadas ou não com nanopartículas de prata, esterilizadas com óxido de etileno (QCOE, n=3; QCNPOE, n=3) ou por radiação ultravioleta (QCRU, n=3; QCNPRU, n=3) e membranas de quitosana obtidas do gládio de lula, esterilizadas com óxido de etileno (GLOE, n=6) ou por radiação ultravioleta (GLRU, n=6). Os mesmos animais foram utilizados em dois grupos experimentais, de forma aleatória, com um intervalo mínimo de sessenta dias entre os procedimentos, respeitando-se o fato de apenas um lado do flanco, esquerdo ou direito, estar em avaliação por período experimental. Após preparo das membranas e implantação no tecido subcutâneo do flanco dos equinos, foram realizadas avaliações macroscópicas e ultrassonográficas das regiões de implante, além de exames físicos, hemogramas e fibrinogênio. Não foram observadas alterações clínicas e laboratoriais. Todos os animais que receberam membranas de quitosana comercial, independente da técnica de preparo, demonstraram rejeição dos biomateriais, uma vez que 100% das feridas cirúrgicas apresentaram deiscência da sutura e expulsão dos implantes. Os animais que receberam as membranas de quitosana de gladio de lula demonstraram sucesso no tratamento, com cicatrização das feridas cirúrgicas por primeira intenção. Conclui-se que membranas de quitosana de gládio de lula são biocompatíveis e biodegradáveis, quando implantadas no tecido subcutâneo do flanco de equinos sadios.(AU)


Assuntos
Animais , Cicatrização , Quitosana/efeitos adversos , Quitosana/uso terapêutico , Cavalos , Implantes de Medicamento
3.
Braz Oral Res ; 33: e086, 2019 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-31483052

RESUMO

Treatment of patients with bisphosphonate usage is a significant concern for oral surgeons because it interferes with jaw bone turnover and regeneration. In case of adverse effects manifesting related to bisphosphonate use, oral surgeons are usually treating and keep the patient's symptoms under control. In this study, we aimed to investigate a new treatment protocol for medication-related osteonecrosis of the jaw (MRONJ). This treatment protocol consisted of administering human parathyroid hormone (hPTH) loaded chitosan microspheres which were prepared by ionotropic gelation method or/and the prepared microspheres were suspended in a poloxamer gel. After in-vitro optimization studies, the efficacy of the chosen formulations was evaluated in-vivo studies. Zoledronic acid was administered daily to forty-eight adult female Sprague-Dawley rats, divided into four experimental groups, at a daily concentration of 0.11 mg/kg over three weeks to induce the MRONJ model. At the end of this period, maxillary left molar teeth were extracted. In the first group, the subjects received no treatment. In the negative control group, poloxamer hydrogel containing empty microspheres were immediately applied to the soft tissues surrounding the extraction socket. The treatment group-1 was treated with local injections of poloxamer hydrogel containing hPTH. The treatment group-2 was treated with a single local injection of poloxamer hydrogel containing hPTH-loaded chitosan microspheres. Both treatment groups received a total of 7 µg of hPTH at the end of the treatment protocol. Our study demonstrates successful attenuation of MRONJ through a local drug delivery system combined with hPTH, as opposed to previously attempted treatment strategies.


Assuntos
Conservadores da Densidade Óssea/farmacologia , Quitosana/farmacologia , Maxila/efeitos dos fármacos , Hormônio Paratireóideo/farmacologia , Animais , Osteonecrose da Arcada Osseodentária Associada a Difosfonatos/tratamento farmacológico , Osteonecrose da Arcada Osseodentária Associada a Difosfonatos/etiologia , Conservadores da Densidade Óssea/efeitos adversos , Conservadores da Densidade Óssea/uso terapêutico , Quitosana/uso terapêutico , Preparações de Ação Retardada , Feminino , Humanos , Maxila/patologia , Microesferas , Modelos Animais , Hormônio Paratireóideo/uso terapêutico , Poloxâmero/administração & dosagem , Poloxâmero/química , Ratos Sprague-Dawley , Ácido Zoledrônico/efeitos adversos
4.
Carbohydr Polym ; 225: 115206, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31521263

RESUMO

Combination chemotherapy has attracted more and more attention in the field of anticancer treatment. Herein, a synergetic targeted combination chemotherapy of doxorubicin (DOX) and cisplatin in breast cancer was realized by HER2 antibody-decorated nanoparticles assembled from aldehyde hyaluronic acid (AHA) and hydroxyethyl chitosan (HECS). Cisplatin and DOX were successively conjugated onto AHA through chelation and Schiff's base reaction, respectively, forming DOX/cisplatin-loaded AHA inner core. The core was sequentially complexed with HECS and targeting HER2 antibody-conjugated AHA. The formed near-spherical nanoplatform had an average size of ∼160 nm and a zeta potential of -28 mV and displayed pH-responsive surface charge reversal and drug release behaviors. HER2 receptor-mediated active targeting significantly enhanced the cellular uptake of nanoplatform. Importantly, DOX and cisplatin exhibited a synergistic cell-killing effect in human breast cancer MCF-7 cells. These results clearly indicate that the novel nanoplatform is promising for synergistic combination chemotherapy of breast cancer.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Quitosana/uso terapêutico , Sistemas de Liberação de Medicamentos/métodos , Ácido Hialurônico/uso terapêutico , Nanopartículas/uso terapêutico , Cisplatino/administração & dosagem , Doxorrubicina/administração & dosagem , Portadores de Fármacos/uso terapêutico , Combinação de Medicamentos , Liberação Controlada de Fármacos , Feminino , Humanos , Células MCF-7
5.
Exp Eye Res ; 188: 107805, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31526807

RESUMO

Macular edema (ME), which is present in various retinal diseases, leads to permanent retinal structural damage and threatens vision. The intravitreal/periocular injection of triamcinolone acetonide (TA) can improve the prognosis of ME; however, further exploration of noninvasive delivery systems is essential. Therefore, as a continuation of our previous study using TA-chitosan coated liposomes (TA-CHLs) as a topical drug delivery system, the present study aimed to determine the drug safety, stability, permeability, and bioavailability of TA-CHLs. The study was based on detecting the delivery of a fluorescent dye to the retina using optical coherence tomography angiography in rats. Marked cellular uptake was observed in cell lines. TA-CHL toxicity was investigated in cell culture. Clinical ocular safety was evaluated by measuring the corneal thickness and intraocular pressure. In preclinical studies on a laser-induced retinal edema rat model, the TA-CHL eye drops had dramatic therapeutic effect in remission of retinal edema over 10 days. These results demonstrated that TA-CHL was nontoxic and had good bioavailability in vitro and in vivo. The results of the present study indicated that this formulation could be an effective therapeutic approach and the TA-CHL eye drops may represent a new option for retinal diseases.


Assuntos
Quitosana/uso terapêutico , Materiais Revestidos Biocompatíveis , Glucocorticoides/uso terapêutico , Lipossomos , Papiledema/tratamento farmacológico , Triancinolona Acetonida/uso terapêutico , Administração Oftálmica , Animais , Disponibilidade Biológica , Barreira Hematorretiniana/efeitos dos fármacos , Quitosana/farmacocinética , Quitosana/toxicidade , Modelos Animais de Doenças , Sistemas de Liberação de Medicamentos , Feminino , Corantes Fluorescentes/metabolismo , Glucocorticoides/farmacocinética , Glucocorticoides/toxicidade , Pressão Intraocular/efeitos dos fármacos , Injeções Intravítreas , Soluções Oftálmicas , Papiledema/fisiopatologia , Ratos , Ratos Endogâmicos BN , Tomografia de Coerência Óptica , Triancinolona Acetonida/farmacocinética , Triancinolona Acetonida/toxicidade , Acuidade Visual/efeitos dos fármacos
6.
Int J Mol Sci ; 20(16)2019 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-31404991

RESUMO

Burns are physically debilitating and potentially fatal injuries. Two marine biomaterials, carboxymethyl chitosan (CMC) and collagen peptides (COP), have emerged as promising burn dressings. In this paper, sponges of carboxymethyl chitosan grafted with collagen peptide (CMC-COP) were prepared by covalent coupling and freeze drying. Scanning electron microscopy (SEM) and Fourier transform infrared (FTIR) spectroscopy were then used to characterize the prepared sponges. To evaluate the wound healing activity of the CMC-COP sponges, in vitro tests including cell viability scratch wound healing and scald wound healing experiments were performed in rabbits. Appearance studies revealed the porous nature of sponges and FTIR spectroscopy demonstrated the successful incorporation of COP into CMC. The in vitro scratch assay showed that treatment with CMC-COP sponges (at 100 µg/mL) had significant effects on scratch closure. For burn wounds treated with CMC-COP, regeneration of the epidermis and collagen fiber deposition was observed on day 7, with complete healing of the epidermis and wound on days 14 and 21, respectively. Based on the pathological examination by hematoxylin and eosinstaining, the CMC-COP group demonstrated pronounced wound healing efficiencies. These results confirmed that the CMC-COP treatment enhanced cell migration and promoted skin regeneration, thereby highlighting the potential application of these sponges in burn care.


Assuntos
Bandagens , Queimaduras/terapia , Quitosana/análogos & derivados , Colágeno/uso terapêutico , Cicatrização , Animais , Linhagem Celular , Quitosana/uso terapêutico , Feminino , Masculino , Peptídeos/uso terapêutico , Coelhos , Cicatrização/efeitos dos fármacos
7.
Int J Mol Sci ; 20(14)2019 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-31315208

RESUMO

Enterotoxigenic Escherichia coli (ETEC) infection destroys the intestinal barrier integrity, in turn, disrupting intestinal homoeostasis. Low-molecular-weight chitosan (LMWC) is a water-soluble chitosan derivative with versatile biological properties. Herein, we examined whether LMWC could relieve ETEC-induced intestinal barrier damage in weaned pigs. Twenty-four weaned pigs were allotted to three treatments: (1) non-infected control; (2) ETEC-infected control; and (3) ETEC infection + LMWC supplementation (100 mg/kg). On day 12, pigs in the infected groups were administered 100 mL of ETEC at 2.6 × 109 colony-forming units/mL to induce intestinal barrier injury. Three days later, serum samples were obtained from all pigs, which were then slaughtered to collect intestinal samples. We evidenced that LMWC not only increased (P < 0.05) the occludin protein abundance but also decreased (P < 0.05) the interleukin-6, tumour necrosis factor-α and mast cell tryptase contents, and the apoptotic epithelial cell percentages, in the small intestine of ETEC-infected pigs. Furthermore, LMWC down-regulated (P < 0.05) the small intestinal expression levels of critical inflammatory- and apoptotic-related genes, such as Toll-like receptor 4 (TLR4) and tumour necrosis factor receptor 1 (TNFR1), as well as the intra-nuclear nuclear factor-κB (NF-κB) p65 protein abundance, in the ETEC-infected pigs. Our study indicated a protective effect of LMWC on ETEC-triggered intestinal barrier disruption in weaned pigs, which involves the repression of intestinal inflammatory responses via blocking the TLR4/NF-κB signalling pathway and the depression of epithelial cell death via TNFR1-dependent apoptosis.


Assuntos
Anti-Inflamatórios/uso terapêutico , Apoptose , Quitosana/uso terapêutico , Infecções por Escherichia coli/tratamento farmacológico , Mucosa Intestinal/efeitos dos fármacos , Animais , Anti-Inflamatórios/farmacologia , Quitosana/farmacologia , Escherichia coli Enterotoxigênica , Interleucina-6/genética , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patologia , Ocludina/genética , Ocludina/metabolismo , Suínos , Receptor 4 Toll-Like/genética , Receptor 4 Toll-Like/metabolismo , Fator de Transcrição RelA/genética , Fator de Transcrição RelA/metabolismo , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/metabolismo
8.
Carbohydr Polym ; 222: 114988, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31320082

RESUMO

This study introduces a novel approach in fabricating bioplatforms with favourable physical, chemical, and mechanical properties for wound dressing applications. The approach employs a three-step method; partial-crosslinking of polymers into soft macromatrices, lyophilization, and pulverization of those macromatrices to obtain polymer particles with improved properties. For investigation of this approach, the ionic polysaccharides, sodium alginate and chitosan were partially crosslinked with calcium chloride and sodium tripolyphosphate, respectively, followed by interpolymer complexation (IPC) for formation of the bioplatform. The formulations displayed good thermal stability with enhanced water uptake. The IPC exhibited water uptake of 4343.4% over 24 h and displayed 78% biodegradation over 14 days, which was superior to that of a commercial alginate-based wound dressing (1612.56% swelling and 16.26% biodegradation). The bioplatform thus possessed promising fluid-absorptivity and biodegradability, for potential application as a wound therapeutic system.


Assuntos
Alginatos/química , Bandagens , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Quitosana/química , Cicatrização , Alginatos/uso terapêutico , Animais , Cloreto de Cálcio/química , Quitosana/uso terapêutico , Camundongos , Células NIH 3T3 , Polifosfatos/química
9.
Int Immunopharmacol ; 75: 105764, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31352327

RESUMO

It is becoming apparent that to obtain robust and prolonged antitumor responses in cancer immunotherapy, appropriate adjunct agents promoting both tumor antigen delivery and immune rejection enhancement are critically required. The semisynthetic biopolymer N-dihydrogalactochitosan (GC) is emerging as a promising such candidate. In the present study, the effects of GC were investigated when combined with cancer vaccines generated by photodynamic therapy (PDT) using mouse tumor model SCCVII (squamous cell carcinoma). The adjunct GC treatment was found to enhance therapeutic benefit obtained with PDT vaccine, while reducing the numbers of myeloid-derived suppressor cells. Another important property of GC is promoting directly the death of SCCVII cells sustaining injury from PDT mediated by various photosensitizers. This effect is extended to cells treated by cryoablation therapy (CAT) performed by exposure to -80 °C. A capacity of GC for preferential binding to PDT treated cells was demonstrated using fluorescence microscopy. In vitro testing with specific caspase-1 inhibitor revealed a pro-survival role of this enzyme in membrane lipid repair mechanisms following combined PDT plus GC treatment. In conclusion, GC represents a uniquely promising adjunct for various PDT protocols, photothermal and similar rapid tumor-ablating therapies.


Assuntos
Adjuvantes Imunológicos/uso terapêutico , Antineoplásicos/uso terapêutico , Vacinas Anticâncer/uso terapêutico , Carcinoma de Células Escamosas/tratamento farmacológico , Quitosana/análogos & derivados , Quitosana/uso terapêutico , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Fotoquimioterapia , Animais , Criocirurgia , Imunoterapia , Camundongos Endogâmicos C3H , Fármacos Fotossensibilizantes/uso terapêutico , Células Tumorais Cultivadas
10.
Int J Dev Neurosci ; 76: 80-85, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31302172

RESUMO

Cytology and histology obstacles have been the main barriers to multiple tissues injury repair. In search of the most promising treatment strategies for spinal cord injury (SCI), stem cell-based transplantation coupled with various materials/technologies have been explored extensively to enhance SCI repair. Chitosan (CS) has demonstrated immense potential for widespread application in the form of scaffolds and micro-particles for SCI repair. The current review summarizes the evidences for stem cell-based transplantation and CS in SCI repair. Stem cells transplantation, which plays a key role in the repair of SCI, mainly results from its neural differentiation potential and neurotrophic effects. Application of CS enhances the survival of grafted stem cells, upregulates the expression level of neurotrophic factors and heightens the neural differentiation of stem cells as well as the functional recovery of spinal cord. Meanwhile, CS can also be exploited as growth factors/RNA carriers to control the release of regenerating molecules which are beneficial to damage spinal cord repair.


Assuntos
Quitosana/uso terapêutico , Traumatismos da Medula Espinal/terapia , Transplante de Células-Tronco , Animais , Humanos , Fatores de Crescimento Neural/administração & dosagem , Fatores de Crescimento Neural/farmacologia , Células-Tronco Neurais , Recuperação de Função Fisiológica , Tecidos Suporte
11.
Anticancer Res ; 39(5): 2415-2427, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31092434

RESUMO

AIM: The purpose of this study was to develop a folate receptor-targeted 68Ga-labeled agent for the detection of cancer cells in mouse models of ovarian cancer by dual positron-emission tomography (PET) and magnetic resonance imaging (MRI). Moreover, we aimed to develop a controlled biopolymer-based chemistry that enables linking metal-binding (here Ga-68) chelators. MATERIALS AND METHODS: The nanoparticle (NP) agent was created by self-assembling of folic acid-modified polyglutamic acid and chelator-modified chitosan followed by radiolabeling with 68Ga (III) ions (68Ga-NODAGA-FA). The structure of modified biopolymers was characterized by spectroscopy. Particle size and mobility were determined. RESULTS: Significant selective binding of NPs was established in vitro using folate receptor-positive KB and - negative MDA-MB-231 cell lines. In vivo tumor uptake of folate-targeted 68Ga3+-radiolabeled NPs was tested using subcutaneous tumor-bearing CB17 SCID mice models. PET/MR dual modalities showed high tumor uptake with 6.5 tumor-to-muscle ratio and NP localization. CONCLUSION: In vivo results supporting the preliminary in vitro tests demonstrated considerably higher 68Ga-NODAGA-FA nanoparticle accumulation in KB tumors than in MDA-MB-231 tumors, thereby confirming the folate receptor-mediated uptake of this novel potential PET imaging agent.


Assuntos
Receptor 1 de Folato/isolamento & purificação , Radioisótopos de Gálio/química , Nanopartículas/química , Neoplasias Ovarianas/diagnóstico por imagem , Acetatos/química , Animais , Quelantes/química , Quitosana/síntese química , Quitosana/química , Quitosana/uso terapêutico , Modelos Animais de Doenças , Feminino , Receptor 1 de Folato/química , Ácido Fólico/química , Radioisótopos de Gálio/uso terapêutico , Compostos Heterocíclicos com 1 Anel/química , Humanos , Imagem por Ressonância Magnética/métodos , Camundongos , Nanopartículas/uso terapêutico , Neoplasias Ovarianas/patologia , Ácido Poliglutâmico/química , Tomografia por Emissão de Pósitrons/métodos
12.
Parasitol Res ; 118(8): 2443-2454, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31144032

RESUMO

Acanthamoeba keratitis (AK) is a devastating, painful corneal infection, which may lead to loss of vision. The development of resistance and failure of the currently used drugs represent a therapeutic predicament. Thus, novel therapies with lethal effects on resistant Acanthamoeba are necessary to combat AK. In the present study, the curative effect of Nigella sativa aqueous extract (N. sativa) and chitosan nanoparticles (nCs) and both agents combined were assessed in experimentally induced AK. All inoculated corneas developed varying grades of AK. The study medications were applied on the 5th day postinoculation and were evaluated by clinical examination of the cornea and cultivation of corneal scraps. On the 10th day posttreatment, a 100% cure of AK was obtained with nCs (100 µg/ml) in grades 1 and 2 of corneal opacity as well as with N. sativa 60 mg/ml-nCs 100 µg/ml in grades 1, 2, and 3 of corneal opacity, highlighting a possible synergistic effect. On the 15th day posttreatment, a 100% cure was reached with N. sativa aqueous extract (60 mg/ml). Moreover, on the 20th day posttreatment, N. sativa (30 mg/ml) provided a cure rate of 87.5%, while nCs (50 µg/ml) as well as N. sativa 30 mg/ml-nCs 50 µg/ml yielded a cure rate of 75%; the lowest percentage of cure (25%) was obtained with chlorhexidine (0.02%), showing a non-significant difference compared to the parasite control. The clinical outcomes were in agreement with the results of corneal scrap cultivation. The results of the present study demonstrate the effectiveness of N. sativa aqueous extract and nCs (singly or combined) when used against AK, and these agents show potential for the development of new, effective, and safe therapeutic alternatives.


Assuntos
Ceratite por Acanthamoeba/tratamento farmacológico , Antiprotozoários/administração & dosagem , Nigella sativa/química , Extratos Vegetais/administração & dosagem , Acanthamoeba/efeitos dos fármacos , Acanthamoeba/fisiologia , Ceratite por Acanthamoeba/parasitologia , Adulto , Animais , Antiprotozoários/química , Quitosana/química , Quitosana/farmacologia , Quitosana/uso terapêutico , Clorexidina/farmacologia , Córnea/parasitologia , Feminino , Humanos , Masculino , Nanopartículas/química , Extratos Vegetais/química , Ratos , Resultado do Tratamento
13.
Molecules ; 24(10)2019 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-31117310

RESUMO

Chitosan-based nanomaterials have attracted significant attention in the biomedical field because of their unique biodegradable, biocompatible, non-toxic, and antimicrobial nature. Multiple perspectives of the proposed antibacterial effect and mode of action of chitosan-based nanomaterials are reviewed. Chitosan is presented as an ideal biomaterial for antimicrobial wound dressings that can either be fabricated alone in its native form or upgraded and incorporated with antibiotics, metallic antimicrobial particles, natural compounds and extracts in order to increase the antimicrobial effect. Since chitosan and its derivatives can enhance drug permeability across the blood-brain barrier, they can be also used as effective brain drug delivery carriers. Some of the recent chitosan formulations for brain uptake of various drugs are presented. The use of chitosan and its derivatives in other biomedical applications is also briefly discussed.


Assuntos
Pesquisa Biomédica , Quitosana/química , Nanoestruturas/química , Anti-Infecciosos/química , Anti-Infecciosos/uso terapêutico , Tecnologia Biomédica , Quitosana/uso terapêutico , Sistemas de Liberação de Medicamentos , Humanos , Nanoestruturas/uso terapêutico
14.
Int J Pediatr Otorhinolaryngol ; 122: 60-69, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30974336

RESUMO

OBJECTIVES: The aim of this study was to investigate the protective effects of a sustained release form of dexamethasone (dex) loaded chitosan-based genipin-cross-linked hydrogel (CBGCH) in a guinea pig model of cisplatin (CP) induced hearing loss. METHODS: Implantation of CBGCH was made by intratympanic (IT) injection. Ototoxicity was produced by intraperitoneal (IP) single dose of 14 mg/kg CP. Animals were randomly divided into four groups with 6 guinea pigs in each. Group 1 received only IP CP; group 2 received only IT dex-loaded CBGCH injections. Group 3 and group 4 received IP CP, plus IT nondrug CBGCH and IT dex-loaded CBGCH respectively 24 h prior to IP CP injections. Distortion product otoacoustic emissions (DPOAEs) and auditory brainstem response (ABR) measurements were obtained before the treatments and solely ABR measurements were done after 3 and 10 days. The ultrastructural effects were investigated by scanning electron microscopy (SEM) analysis. RESULTS: The postCP ABR thresholds at 4, 8, 12, 16, 32 kHz frequencies were significantly better in group 4 than groups 1 and 3 (p < 0.05). The comparison of time effective ABR thresholds between groups 1 and 4 and between groups 3 and 4 showed significantly lower ABR thresholds in group 4 (p < 0.05). The SEM analysis showed that stereocilia of inner and outer hair cells were preserved in group 4, almost like group 2, whereas cytotoxic degenerations were noted in groups 1 and 3. CONCLUSIONS: Intratympanic administration of dex-loaded CBGCH has been shown to provide functional and structural protection against CP-induced ototoxicity.


Assuntos
Anti-Inflamatórios/uso terapêutico , Colagogos e Coleréticos/uso terapêutico , Dexametasona/uso terapêutico , Perda Auditiva/prevenção & controle , Iridoides/uso terapêutico , Animais , Anti-Inflamatórios/administração & dosagem , Antineoplásicos/efeitos adversos , Limiar Auditivo/efeitos dos fármacos , Materiais Biocompatíveis/uso terapêutico , Quitosana/uso terapêutico , Cisplatino/efeitos adversos , Preparações de Ação Retardada/uso terapêutico , Dexametasona/administração & dosagem , Combinação de Medicamentos , Potenciais Evocados Auditivos do Tronco Encefálico/efeitos dos fármacos , Cobaias , Células Ciliadas Auditivas Internas , Células Ciliadas Auditivas Externas , Perda Auditiva/induzido quimicamente , Hidrogéis/uso terapêutico , Masculino , Microscopia Eletrônica de Varredura , Emissões Otoacústicas Espontâneas/efeitos dos fármacos , Distribuição Aleatória , Estereocílios/ultraestrutura
15.
Oxid Med Cell Longev ; 2019: 7658052, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30984339

RESUMO

We explored the effects of chitosan oligosaccharides (COS) on coronary heart disease (CHD) patients. The component of COS was measured by matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS). CHD patients were evenly assigned into the COS group (COG) and the placebo group (CG). The duration of treatment was 6 months and therapeutic results were explored by measuring left ventricular ejection fraction (LVEF) value, Lee scores, quality of life (QOL), blood urea nitrogen, and serum creatinine. The intestinal flora were determined by 16s rDNA sequencing. The circulating antioxidant levels and lipid profiles were compared between two groups. There were 7 different degrees of polymerization (DP4-10) in COS. Lee scores, QOL scores, and LVEF values in the COG group were higher than those in the CG group (P < 0.05). COS treatment improved blood urea nitrogen and serum creatinine when compared with controls (P < 0.05). Circulating antioxidant levels were higher in the COG group than in the CG group. COS consumption increased the serum levels of SOD and GSH and reduced the levels of ALT and AST (P < 0.05). Meanwhile, lipid profiles were improved in the COG group. COS consumption increased the abundance of Faecalibacterium, Alistipes, and Escherichia and decreased the abundance of Bacteroides, Megasphaera, Roseburia, Prevotella, and Bifidobacterium (P < 0.05). On the other hand, COS consumption increased the probiotic species Lactobacillus, Lactococcus, and Phascolarctobacterium. The increased species have been reported to be associated with antioxidant properties or lipid improvement. COS had similar effects with chitohexaose on the growth rate of these species. Therefore, COS ameliorate the symptoms of CHD patients by improving antioxidant capacities and lipid profiles via the increase of probiotics in the intestinal flora.


Assuntos
Quitosana/uso terapêutico , Doença das Coronárias/tratamento farmacológico , Probióticos/metabolismo , Qualidade de Vida/psicologia , Adulto , Antioxidantes , Quitosana/farmacologia , Feminino , Humanos , Masculino , Oligossacarídeos
16.
Int J Biol Macromol ; 132: 922-928, 2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-30930269

RESUMO

The lipid-lowering activities of chitosan (CS) and its quaternary ammonium salt (HACC) with two molecular weights (CS1, 2.5 × 105; HACC1, 2.4 × 105; CS2, 3.8 × 104; HACC2, 3.5 × 104) were evaluated for the rats fed with high-fat diets, respectively. The results showed that oral four CS samples resulted in the significant decrease of food efficiency ratio with the increase of fecal fat and cholesterol excretion (P < 0.05) compared with high-fat control group. Furthermore, the lipid-mediated oxidative stress and lipid levels in plasma and liver reduced, and hepatic lipase and lipoprotein lipase activities increased after the administration of CS and HACC. But the lipid-lowering effects of the four CS samples were different, which was HACC2 > HACC1 > CS2 > CS1 successively. The findings indicated that CS and HACC could reduce the absorption of dietary fat and cholesterol in vivo, which helped to alleviate hyperlipidemia and fatty liver effectively in the rats.


Assuntos
Quitosana/química , Quitosana/farmacologia , Dieta Hiperlipídica/efeitos adversos , Hiperlipidemias/tratamento farmacológico , Hipolipemiantes/química , Hipolipemiantes/farmacologia , Compostos de Amônio Quaternário/química , Animais , Quitosana/uso terapêutico , Hiperlipidemias/sangue , Hiperlipidemias/induzido quimicamente , Hiperlipidemias/metabolismo , Hipolipemiantes/uso terapêutico , Lipase/sangue , Lipase/metabolismo , Lipídeos/sangue , Fígado/efeitos dos fármacos , Fígado/enzimologia , Fígado/metabolismo , Masculino , Estresse Oxidativo/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley
17.
Carbohydr Polym ; 214: 80-89, 2019 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-30926011

RESUMO

Carboxymethyl chitosan (CMCS), a water-soluble derivative of chitosan possessing numerous enhanced physicochemical and biological properties, has emerged as a promising biopolymer carrier for new drug delivery. Norcantharidin (NCTD) is an effective anti-tumor compound with severe nephrotoxicity. In this study, norcantharidin-conjugated carboxymethyl chitosan (CMCS-NCTD) was synthesized to reduce systemic toxicity and improve anti-tumor efficiency of NCTD. Our results demonstrated that CMCS-NCTD could significantly inhibit migration of tumor cells both in vitro and in vivo in a dose-dependent manner (P < 0.05). The enhanced anti-tumor effects of CMCS-NCTD were confirmed by inhibiting the growth of solid tumors and extending survival time of tumor-bearing mice. Further investigation for the underlying mechanisms indicated that CMCS-NCTD could inhibit tumor angiogenesis and reduce degradation of extracellular matrix by regulating the expressions of VEGF, MMP-9 and TIMP-1. Overall, our findings suggested that CMCS-NCTD was an excellent polymer derivative for cancer treatment, and CMCS was a promising platform for efficient delivery of anti-cancer drugs.


Assuntos
Antineoplásicos/uso terapêutico , Compostos Bicíclicos Heterocíclicos com Pontes/uso terapêutico , Carcinoma Pulmonar de Lewis/tratamento farmacológico , Quitosana/análogos & derivados , Portadores de Fármacos/uso terapêutico , Neovascularização Patológica/prevenção & controle , Células A549 , Animais , Antineoplásicos/síntese química , Antineoplásicos/química , Antineoplásicos/toxicidade , Compostos Bicíclicos Heterocíclicos com Pontes/síntese química , Compostos Bicíclicos Heterocíclicos com Pontes/química , Compostos Bicíclicos Heterocíclicos com Pontes/toxicidade , Sequência de Carboidratos , Carcinoma Pulmonar de Lewis/patologia , Movimento Celular/efeitos dos fármacos , Quitosana/síntese química , Quitosana/química , Quitosana/uso terapêutico , Quitosana/toxicidade , Regulação para Baixo , Portadores de Fármacos/síntese química , Portadores de Fármacos/química , Portadores de Fármacos/toxicidade , Feminino , Humanos , Pulmão/patologia , Masculino , Metaloproteinase 9 da Matriz/metabolismo , Camundongos Endogâmicos C57BL , Solubilidade , Inibidor Tecidual de Metaloproteinase-1/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo
18.
J Orthop Res ; 37(4): 867-876, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30816583

RESUMO

Among conventional osteoarthritis (OA) treatments, intra-articular (i.a) viscosupplementation with hyaluronic acid (HA) is used to restore joint viscoelasticity. However, the rapid clearance and elimination of HA may limit its application. The aim of this study was to verify the improved efficacy of HA within the joint, using a lactose-modified chitosan (chitlac) as a potentially chondroprotective additive. Four weeks after induction of experimental OA by destabilization of the medial meniscus (DMM), 12-week-old Sprague Dawley male rats (n = 30), received once a week, for three weeks, i.a injections of: (i) HA associated to chitlac (ARTY-DUO®), (ii) HA; and (iii) sodium chloride (NaCl). Five animals for each group were euthanized 4 weeks after the first i.a injection, while the remaining five were euthanized 8 weeks after the first i.a injection. The restoration of physiological joint microenvironment was tested by histology, histomorphometry, immunohistochemistry, and microtomography (micro-CT). At 4 and even more at 8 weeks, histological analysis showed a significant decrease in OARSI and Mankin scores, with weaker matrix metalloproteinase (MMP)-3, MMP-13, and Galectin-3 in ARTY-DUO® group versus NaCl and HA groups. A reduction in Galectin-1 and a stronger Collagen II staining was seen in both ARTY-DUO® and HA versus NaCl. A reduction in Kreen-modified score, for synovium inflammation, was observed in the ARTY-DUO® group. Micro-CT measurements did not shown significant differences between the groups. The present results show that i.a ARTY-DUO® injections produce a significant improvement in knee articular cartilage degeneration and synovium inflammation in a rat model of DMM-induced OA. © 2019 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res.


Assuntos
Quitosana/análogos & derivados , Quitosana/uso terapêutico , Ácido Hialurônico/uso terapêutico , Lactose/química , Osteoartrite do Joelho/tratamento farmacológico , Viscossuplementos/uso terapêutico , Animais , Quitosana/química , Avaliação Pré-Clínica de Medicamentos , Injeções Intra-Articulares , Masculino , Ratos Sprague-Dawley
19.
J Altern Complement Med ; 25(5): 552-558, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30758216

RESUMO

Objective: An alcohol-free mouthwash of curcuminoids purified from the turmeric (Curcuma longa Linn.) rhizome was formulated using a cosolvent system, comprising chitosan and polyethylene glycol (PEG) 400, and determined for its efficacy and safety in management of denture stomatitis (DS) in comparison with a chlorhexidine (CHX) mouthwash. Design: A single-center, randomized, controlled parallel-arm trial was conducted. Setting: The study took place at the Faculty of Dentistry, Prince of Songkla University, Hat-Yai, Thailand, between June 2016 and June 2017. Subjects: Participants were 20 years old or older adults of both genders, using removable dentures, and with a confirmed diagnosis of DS from an oral medicine specialist. Interventions: A total of 30 patients were randomly assigned to 3 different interventions, including the chitosan-curcuminoid (CHI-CUR) mouthwash, CHX mouthwash, and a vehicle formulation comprising chitosan and PEG 400. Ten milliliters of each intervention was given to the patient to be used for 30 sec, three times a day at 8 am, 12 pm, and 4 pm, for 2 weeks. Outcome measures: Outcome measures included complete relief of erythematous lesions under the denture and reduction in the number of candida colonies present in the denture-fitting surface. Results: Eight of 10 patients (80%) using the CHI-CUR mouthwash had a complete response after the 2-week treatment course compared with 30% of patients using the CHX mouthwash (p < 0.05). Both interventions exerted comparable anticandida efficacy. No oral or systemic adverse events that could possibly be related to the use of mouthwash were documented. Conclusions: The finding indicated that an alcohol-free CHI-CUR mouthwash may serve as a safe and potential topical therapeutic alternative in treating generalized or candida-associated DS.


Assuntos
Quitosana/uso terapêutico , Clorexidina/uso terapêutico , Curcumina/uso terapêutico , Antissépticos Bucais , Estomatite sob Prótese/tratamento farmacológico , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Antissépticos Bucais/efeitos adversos , Antissépticos Bucais/química , Antissépticos Bucais/uso terapêutico , Satisfação do Paciente , Resultado do Tratamento
20.
Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi ; 33(2): 185-189, 2019 02 15.
Artigo em Chinês | MEDLINE | ID: mdl-30739412

RESUMO

Objective: To study the effect of intraarticular injection of crosslinked-chitosan in the treatment of knee osteoarthritis in rabbits. Methods: Thirty-two New Zealand white rabbits were randomly divided into 4 groups (groups A, B, C, and D; 8 rabbits in each group). The knee osteoarthritis models were prepared by anterior cruciate ligament transection in the left hind in groups A, B, and C. At 4 weeks after operation, the rabbits were received intraarticular injection of 0.6 mL crosslinked-chitosan in group A, 0.3 mL chitosan (once per 2 weeks, for twice) in group B, and 0.3 mL saline (once per 2 weeks, for twice) in group C. The rabbits in group D were treated with sham operation in the left hind, and received intraarticular injection of 0.3 mL saline (once per 2 weeks, for twice). At 8 weeks, the macroscopic observation, histological examination (HE staining, Safranin-fast green double staining, and Mankin score), scanning electron microscopy (SEM) observation, and immunohistochemical staining of collagen type Ⅱ were performed. Results: Macroscopic and SEM observations showed that the cartilage in group D was basically the same as normal and better than that in groups A and B, and the abrasion of cartilage in group C was the most serious. The histological observation results in groups A and B were slightly similar and better than those in group C, but not up to the structure of group D. The macroscopic score and Mankin score of groups B and C were significantly higher than those of group D ( P<0.05), and there was no significant difference between group A and group B ( P>0.05). Immunohistochemical staining results showed that the collagen type Ⅱ positive percentage of chondrocytes was significantly higher in group D than that in groups B and C, and no significant difference was found between group A and group B ( P>0.05). Conclusion: The crosslinked-chitosan can significantly improve the osteoarthritis of the rabbit knee, delay the pathological changes of osteoarthritis, and decrease the frequency of injection.


Assuntos
Cartilagem Articular , Quitosana , Osteoartrite do Joelho , Animais , Quitosana/uso terapêutico , Condrócitos , Modelos Animais de Doenças , Articulação do Joelho , Osteoartrite do Joelho/terapia , Coelhos , Distribuição Aleatória
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