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1.
Carbohydr Polym ; 261: 117869, 2021 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-33766356

RESUMO

Osteoarthritis (OA) is an age-related joint disorder and one of the leading causes of physical disability. In this study, we designed and synthesized a new polysaccharide complex, carboxymethyl chitosan strontium (CMCS-Sr), which is believed to have positive effects on relieving OA. The synthesized CMCS-Sr was structurally verified by SEM, EDS, FTIR, etc. The therapeutic effects of CMCS-Sr were evaluated using various biological experiments. The cell viability and apoptosis results reveal that CMCS-Sr can significantly promote the proliferation and suppress OA chondrocytes apoptosis in vitro. The immunofluorescence staining results suggest that CMCS-Sr facilitates the promotion of the secretion of Type II collagen (Col-II). The transcriptomic results support the observed positive effects of CMCS-Sr on inhibiting chondrocytes apoptosis and alleviating inflammatory reactions. Moreover, animal study demonstrates that CMCS-Sr effectively reduced articular cartilage damage and subchondral bone degradation. Therefore, we propose the use of CMCS-Sr as a promising candidate for relieving OA.


Assuntos
Quitosana/análogos & derivados , Osteoartrite/tratamento farmacológico , Polímeros/síntese química , Polímeros/uso terapêutico , Estrôncio/química , Animais , Cartilagem Articular/efeitos dos fármacos , Cartilagem Articular/patologia , Células Cultivadas , Quitosana/síntese química , Quitosana/química , Quitosana/farmacologia , Quitosana/uso terapêutico , Condrócitos/efeitos dos fármacos , Condrócitos/patologia , Condrócitos/fisiologia , Humanos , Masculino , Osteoartrite/patologia , Polímeros/química , Polímeros/farmacologia , Cultura Primária de Células , Ratos , Estrôncio/farmacologia , Estrôncio/uso terapêutico
2.
Carbohydr Polym ; 261: 117870, 2021 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-33766357

RESUMO

Effective wound dressings are of great significance in preventing infections and promoting wound healing. However, most existing hydrogel dressings have an inadequacy in either mechanical performance, biological activities, or versatilities. Here we presented a double-network cross-linked polysaccharide-based hydrogel composed of collagen peptide-functionalized carboxymethyl chitosan (CS) and oxidized methacrylate sodium alginate (SA). The hydrogel possessed interconnected porous morphologies, suitable swelling ratios, excellent mechanical properties, and favorable biocompatibility. Meanwhile, the in vivo studies using a mouse full-thickness skin defect model showed that the double-network CS/SA hydrogel significantly accelerated wound healing by regulating the inflammatory process, promoting collagen deposition, and improving vascularization. Therefore, the functionalized double-network hydrogel should be a potential candidate as wound dressings.


Assuntos
Curativos Hidrocoloides , Hidrogéis , Polissacarídeos/química , Cicatrização/efeitos dos fármacos , Alginatos/síntese química , Alginatos/química , Alginatos/uso terapêutico , Animais , Células Cultivadas , Quitosana/análogos & derivados , Quitosana/síntese química , Quitosana/química , Quitosana/uso terapêutico , Colágeno/síntese química , Colágeno/química , Colágeno/farmacocinética , Colágeno/uso terapêutico , Humanos , Hidrogéis/síntese química , Hidrogéis/química , Hidrogéis/uso terapêutico , Teste de Materiais , Camundongos , Fragmentos de Peptídeos/síntese química , Fragmentos de Peptídeos/química , Fragmentos de Peptídeos/farmacocinética , Fragmentos de Peptídeos/uso terapêutico , Polissacarídeos/uso terapêutico , Pele/efeitos dos fármacos , Pele/lesões , Pele/patologia
3.
Br J Oral Maxillofac Surg ; 59(2): 191-196, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33483157

RESUMO

We undertook this study to assess the analgesic and anti-inflammatory properties of ibuprofen when administered through two drug delivery systems after mandibular third molar surgery. The study was conducted on 100 patients who required the surgical removal of impacted mandibular third molars under local anaesthesia. The study subjects were divided into two groups of 50 patients each. Patients in the study group were given ibuprofen-incorporated chitosan-based microspheres, which were packed into the third molar sockets after removal of impacted teeth. Patients in the control group were prescribed with ibuprofen 400mg tablets that were to be administered orally after the removal of impacted mandibular third molars. All patients were assessed for pain, swelling, and trismus on the second, fourth, and seventh postoperative days, and wound healing was assessed on the seventh postoperative day. Patients in the study group had significantly less pain and comparatively better mouth opening on the second, fourth, and seventh postoperative days, which showed clinically and statistically significant results of p<0.05, respectively, while the assessment of swelling for the study group did not show statistically significant results on any of the three postoperative days. Among 50 patients in the study group, two had wound gaping, and among 50 patients in the control group, four presented with wound gaping and three patients developed dry socket. Ibuprofen-incorporated chitosan-based microspheres (study group) had comparatively better analgesic and anti-inflammatory properties with drastic reduction of pain, swelling, trismus, and also had a reliable wound healing property when compared with the orally-administered ibuprofen (control group) after mandibular third molar surgery.


Assuntos
Quitosana , Preparações Farmacêuticas , Dente Impactado , Anti-Inflamatórios/uso terapêutico , Quitosana/uso terapêutico , Sistemas de Liberação de Medicamentos , Edema/tratamento farmacológico , Edema/etiologia , Edema/prevenção & controle , Humanos , Ibuprofeno/uso terapêutico , Mandíbula/cirurgia , Microesferas , Dente Serotino/cirurgia , Dor Pós-Operatória/tratamento farmacológico , Dor Pós-Operatória/prevenção & controle , Extração Dentária , Dente Impactado/cirurgia , Trismo/etiologia , Trismo/prevenção & controle
4.
Int J Mol Sci ; 22(3)2021 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-33498889

RESUMO

Chitosan and its derivative, chitosan oligosaccharide (CO), possess hypolipidemic and anti-obesity effects. However, it is still unclear if the mechanisms are different or similar between chitosan and CO. This study was designed to investigate and compare the effects of CO and high-molecular-weight chitosan (HC) on liver lipogenesis and lipid peroxidation, adipose lipolysis, and intestinal lipid absorption in high-fat (HF) diet-fed rats for 12 weeks. Rats were divided into four groups: normal control diet (NC), HF diet, HF diet+5% HC, and HF diet+5% CO. Both HC and CO supplementation could reduce liver lipid biosynthesis, but HC had a better effect than CO on improving liver lipid accumulation in HF diet-fed rats. The increased levels of triglyceride decreased lipolysis rate, and increased lipoprotein lipase activity in the perirenal adipose tissue of HF diet-fed rats could be significantly reversed by both HC and CO supplementation. HC, but not CO, supplementation promoted liver antioxidant enzymes glutathione peroxidase and superoxide dismutase activities and reduced liver lipid peroxidation. In the intestines, CO, but not HC, supplementation reduced lipid absorption by reducing the expression of fabp2 and fatp4 mRNA. These results suggest that HC and CO have different mechanisms for improving lipid metabolism in HF diet-fed rats.


Assuntos
Quitosana/farmacologia , Dieta Hiperlipídica/efeitos adversos , Metabolismo dos Lipídeos/efeitos dos fármacos , Obesidade/metabolismo , Tecido Adiposo/metabolismo , Animais , Quitosana/uso terapêutico , Absorção Intestinal , Peroxidação de Lipídeos , Lipogênese , Lipólise , Fígado/metabolismo , Masculino , Obesidade/tratamento farmacológico , Obesidade/etiologia , Ratos , Ratos Sprague-Dawley
5.
Int J Biol Macromol ; 169: 321-329, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-33310094

RESUMO

Osteosarcoma has a high prevalence among children and adolescents. Common treatments of this disease are not promising enough. Molecular processes involved in the pathogenesis of osteosarcoma are not fully understood. Besides, the remnants of tumor cells after surgery can cause bone destruction and recurrence of the disease. Thus, there is a need to develop novel drugs or enhancing the currently-used drugs as well as identifying bone-repairing methods. Chitosan is a natural compound produced by the deacetylation of chitin. Research has shown that chitosan can be used in various fields due to its beneficial effects, such as biodegradability and biocompatibility. Regarding cancer, chitosan exerts several anti-tumor activities. Moreover, it can be used in diagnostic techniques, drug delivery systems, and cell culture methods. Herein, we aim to discuss the potential roles of chitosan in studying and treating osteosarcoma. We review the literature on chitosan's applications as a drug delivery system and how it can be combined with other substances to improve its ability of local drug delivery. We take a look into the studies concerning the possible benefits of chitosan in the field of bone tissue engineering and 3D culturing. Furthermore, anti-cancer activities of different compounds of chitosan are reviewed.


Assuntos
Quitosana/uso terapêutico , Osteossarcoma/tratamento farmacológico , Materiais Biocompatíveis/uso terapêutico , Neoplasias Ósseas/tratamento farmacológico , Quitina/química , Quitina/farmacologia , Quitosana/metabolismo , Sistemas de Liberação de Medicamentos/métodos , Humanos , Engenharia Tecidual/métodos
6.
Carbohydr Polym ; 252: 117162, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33183613

RESUMO

In order to overcome treatment difficulty of S. aureus infections, a pH/hyaluronidase dual responsive enrofloxacin-cyclodextrin (ß-CD) inclusion complexes (IC) containing hyaluronic acid/chitosan (HA/CS) self-assemble composite nanosystems covered by poloxamer 188 (F68) was firstly explored for targeted "on-demand" delivery. The FTIR, DSC and PXRD showed that enrofloxacin was embedded into IC and then distributed into F68 coating nanogels formulated by electrostatic interaction between CS and HA. The optimal nanosystems of 118.8 ± 30.7 nm showed excellent stability and responsive release in the acid medium, hyaluronidase containing medium, and LB broth medium where S. aureus present. The nanosystems displayed strong surface adsorption on S. aureus and enhanced activity against S. aureus. It had stronger sustained release than the polymeric nanoparticles formulated by entrapping of IC into F68 and the single HA/CS nanogels. This study provides a promising multi-functionalized nanosystems to overcome the treatment challenge of S. aureus and other bacterial infections.


Assuntos
Antibacterianos/farmacologia , Ciclodextrinas/farmacologia , Enrofloxacina/farmacologia , Nanogéis/química , Staphylococcus aureus/efeitos dos fármacos , Quitosana/química , Quitosana/uso terapêutico , Portadores de Fármacos , Liberação Controlada de Fármacos , Ácido Hialurônico/química , Ácido Hialurônico/uso terapêutico , Hialuronoglucosaminidase/metabolismo , Concentração de Íons de Hidrogênio , Nanogéis/uso terapêutico , Poloxâmero/química , Poloxâmero/uso terapêutico , Infecções Estafilocócicas/tratamento farmacológico
7.
Int J Biol Macromol ; 170: 207-221, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-33359612

RESUMO

Wounds are often recalcitrant to traditional wound dressings and a bioactive and biodegradable wound dressing using hydrogel membranes can be a promising approach for wound healing applications. The present research aimed to design hydrogel membranes based on hyaluronic acid, pullulan and polyvinyl alcohol and loaded with chitosan based cefepime nanoparticles for potential use in cutaneous wound healing. The developed membranes were evaluated using dynamic light scattering, proton nuclear magnetic resonance, Fourier transform infrared spectroscopy, thermogravimetric analysis, and scanning electron microscopy. The results indicated the novel crosslinking and thermal stability of the fabricated hydrogel membrane. The in vitro analysis demonstrates that the developed membrane has water vapors transmission rate (WVTR) between 2000 and 2500 g/m2/day and oxygen permeability between 7 and 14 mg/L, which lies in the range of an ideal dressing. The swelling capacity and surface porosity to liberate encapsulated drug (cefepime) in a sustained manner and 88% of drug release was observed. The cefepime loaded hydrogel membrane demonstrated a higher zone of inhibition against Staphylococcus aureus, Pseudomonas aeruginosa, and Escherichia coli and excisional rat model exhibit expeditious recovery rate. The developed hydrogel membrane loaded with cefepime nanoparticles is a promising approach for topical application and has greater potential for an accelerated wound healing process.


Assuntos
Curativos Biológicos , Quitosana/uso terapêutico , Membranas Artificiais , Cicatrização/efeitos dos fármacos , Animais , Antibacterianos/administração & dosagem , Antibacterianos/uso terapêutico , Cefepima/administração & dosagem , Cefepima/uso terapêutico , Técnicas de Química Analítica , Quitosana/administração & dosagem , Quitosana/química , Portadores de Fármacos/administração & dosagem , Liberação Controlada de Fármacos , Escherichia coli/efeitos dos fármacos , Feminino , Glucanos/química , Ácido Hialurônico/química , Hidrogéis/administração & dosagem , Hidrogéis/química , Masculino , Teste de Materiais , Microscopia Eletrônica de Varredura , Nanopartículas/administração & dosagem , Álcool de Polivinil/química , Porosidade , Pseudomonas aeruginosa/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Staphylococcus aureus/efeitos dos fármacos , Resistência à Tração
8.
Acta Cir Bras ; 35(8): e202000803, 2020 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-32901680

RESUMO

PURPOSE: To evaluate different concentrations of ciprofloxacin to prevent infection after open fracture contaminated with S. aureus in rats using absorbable local delivery system. METHODS: Fifty-two Wistar rats were assigned to six groups. After 4 weeks, all animals underwent 99mTc-ceftizoxima scintigraphy evaluation, callus formation measurement and histological analysis. ANOVA, t-Student and Kruskal Wallis were used for quantitative variables statistical analysis, whereas qui square and exact Fisher were used for qualitative variables. RESULTS: Treatment using 25% and 50% of ciprofloxacin incorporated at the fracture fixation device were effective in preventing bone infection compared to control group (p<0.05). Chitosan were not effective in preventing bone infection when used alone compared to control group (p>0.05). Histological findings demonstrated bone-healing delay with 50% of ciprofloxacin. No difference in callus formation were observed (p>0.05). CONCLUSION: Local delivery treatment for contaminated open fracture using chitosan with ciprofloxacin is effective above 25%.


Assuntos
Quitosana , Ciprofloxacino , Fraturas do Fêmur , Fraturas Expostas , Controle de Infecções , Animais , Calo Ósseo , Quitosana/uso terapêutico , Ciprofloxacino/uso terapêutico , Fraturas do Fêmur/complicações , Fraturas do Fêmur/cirurgia , Consolidação da Fratura , Humanos , Infecções , Ratos , Ratos Wistar , Staphylococcus aureus
9.
Med. oral patol. oral cir. bucal (Internet) ; 25(5): e644-e651, sept. 2020.
Artigo em Inglês | IBECS | ID: ibc-196520

RESUMO

BACKGROUND: The aim of this study was to evaluate and compare the postoperative effect of a topic gel containing chlorhexidine, chitosan, allantoine and dexpanthenol versus a placebo for pain and inflammation control after third molar surgery. MATERIAL AND METHODS: A gel combining 0.2% chlorhexdine, 0.5% chitosan, 5% dexpanthenol, 0.15% allantoin and 0.01% sodium saccharin was selected for this split mouth randomized controlled and double-blind trial including 36 patients with bilaterally and symmetrically impacted lower third molars. The teeth (n = 72) were randomly divided into two groups before surgical removal: control group (CG; in which a placebo was given) and experimental group (EG). Swelling, trismus, postoperative pain, wound healing and complications were measured and recorded in order to evaluate differences between the placebo and experimental product. RESULTS: Five patients suffered from an alveolitis in the CG (13.9%), and none in the study group (0%), but no statistically significant difference was found (p = 0.063). From day 0 to day 7, trismus and swelling were significantly less pronounced in the EG, and wound healing was considered 'good' in 22.2% for the CG and 97.2% for the EG (p < 0.001). Mean VAS scores during the seven postoperative days were statistically lower in the study (2.56 ± 1,19) compared to the placebo group (3.25 ± 1.6) (p = 0.002). The mean consumption of analgesic pills during the first 92 hours was also statistically lower in the EG (0.26 ± 0.51) in comparison to the CG (0.56 ± 0.67) (p = 0.003). CONCLUSIONS: The use of an experimental gel containing chlorhexidine, chitosan, allantoine and dexpanthenol seems to significantly reduce postoperative pain, trismus and signs of inflammation. Future studies should further evaluate, if the gel is effective in dry socket preventing after third molar removal


No disponible


Assuntos
Humanos , Masculino , Feminino , Adulto Jovem , Adulto , Dente Serotino/cirurgia , Extração Dentária/métodos , Dor Pós-Operatória/prevenção & controle , Quitosana/uso terapêutico , Clorexidina/uso terapêutico , Alantoína/uso terapêutico , Ácido Pantotênico/análogos & derivados , Complicações Pós-Operatórias/prevenção & controle , Anti-Inflamatórios/uso terapêutico , Administração Tópica , Géis/uso terapêutico , Estatísticas não Paramétricas , Resultado do Tratamento , Medição da Dor , Fatores de Tempo , Trismo/prevenção & controle , Método Duplo-Cego
10.
Med. oral patol. oral cir. bucal (Internet) ; 25(4): e488-e494, jul. 2020. tab
Artigo em Inglês | IBECS | ID: ibc-196501

RESUMO

BACKGROUND: Previous studies have shown that radiotherapy of the head and neck region can cause direct changes in dental structure. This study evaluated the effect of different solutions on the dentin chemical composition and collagen structure of irradiated dentin. MATERIAL AND METHODS: Sixty maxillary canines were distributed in 2 groups (n = 30): non-irradiated and irradiated (radiotherapy: X-rays of 6 MV in 30 cycles of 2 Gy to 60 Gy). The teeth were sectioned, sanded, and polished to obtain 3x3x2 mm fragments, which were redistributed in 3 subgroups (n = 10) according to the treatment employed: chlorhexidine 2% (CL), chitosan 0.2% (QT), and 0.5 M carbodiimide (EDC). The samples were analyzed in FTIR at time zero (T0-control) and after 1 (T1), 3 (T3), and 5 (T5) minutes of immersion in the tested solutions. The data for the areas of the carbonate (C), amide I (AI) bands, and the ratio between the areas of the amide III/proline and hydroxyproline (AIII/PH) bands were analyzed using ANOVA and Tukey test (alpha = 5%).RESULTS: QT showed lower C values at T1, T3, and T5 (P < 0.0001), presenting lower values when compared to CL and EDC subgroups (P < 0.05). AI values at T3 and T5 were higher than T0-control and T1, independently of the radiotherapy and dentin treatment factors (P < 0.05). At T0-control, the AIII/PH ratio was lower in the irradiated group (P < 0.05), whereas the EDC treatment at T1, T3, and T5 and QT at T3 and T5 increased these values (P < 0.05), making them similar to non-irradiated subgroups (P>0.05). CONCLUSIONS: Radiotherapy changes the secondary structure of collagen, and EDC was able to restore collagen integrity after 1 minute of immersion, without changing dentin inorganic composition


No disponible


Assuntos
Humanos , Dentina/efeitos da radiação , Lesões por Radiação/prevenção & controle , Clorexidina/uso terapêutico , Quitosana/uso terapêutico , Carbodi-Imidas/uso terapêutico , Radioterapia/efeitos adversos , Análise de Variância , Estatísticas não Paramétricas , Fatores de Tempo , Propriedades de Superfície , Reprodutibilidade dos Testes , Espectroscopia de Infravermelho com Transformada de Fourier , Imersão
11.
Am J Sports Med ; 48(8): 1961-1966, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32520591

RESUMO

BACKGROUND: BST-CarGel (CarGel) is an injectable chitosan scaffold that is mixed with fresh, autologous blood and injected into the site of microfracture (MF) to physically stabilize clots and enhance cartilage repair. PURPOSE: To evaluate short-term clinicoradiological outcomes of patients treated arthroscopically for acetabular chondral defects with CarGel in conjunction with MF compared with those treated with MF alone. STUDY DESIGN: Cohort study; Level of evidence, 3. METHODS: All patients who underwent hip arthroscopy and received MF with or without CarGel for acetabular chondral defects between 2014 and 2018 with a minimum 2-year clinicoradiological follow-up were included. Intraoperative details, postoperative complications, and clinical outcome scores, including the international Hip Outcome Tool-33 (iHOT-33), Hip Outcome Score (HOS)-Activities of Daily Living (HOS-ADL), and Hip Outcome Score-Sports Profile, were analyzed. Serial plain radiographs were assessed independently by 2 blinded observers. A survival analysis was performed to identify the number of cases converted to total hip arthroplasty (THA) in both groups, which was correlated with the cartilage defect size at the time of surgery. RESULTS: Eighty patients (54 CarGel and 26 MF) were evaluated, including 56 men (70%) and 48 right hips (60%). Three patients were lost to follow-up. There were no major adverse events in either group. The average defect size was 3.63 and 4.97 cm2 in MF and CarGel, respectively (P = .002). There was a statistically significant improvement in iHOT-33 (from 43.24 to 60.17 in MF and from 41.13 to 58.39 in CarGel) and HOS-ADL (from 62.25 to 76.75 in MF and from 44.69 to 79.16 in CarGel) scores. There was no difference between the 2 groups in the outcome scores after adjusting for covariates. Survival analysis showed 34.6% of MF cases and 5.9% of CarGel cases were converted to THA (P = .001). The mean defect size of the failure group was higher in CarGel than in MF (8.83 and 3.72 cm2, respectively). Mean joint space reduction was 1.41 mm in MF and 0.19 mm in CarGel (P < .001). CONCLUSION: Two-year clinicoradiological results were promising in these lesions that are difficult to treat. Arthroscopic treatment of chondral acetabular defects with CarGel demonstrated a significant decrease in progressive loss of joint space and conversion to THA compared with MF as an isolated procedure.


Assuntos
Acetábulo/lesões , Cartilagem/lesões , Quitosana/uso terapêutico , Fraturas de Estresse/terapia , Articulação do Quadril/cirurgia , Tecidos Suporte , Atividades Cotidianas , Adulto , Artroscopia , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento
12.
J Dairy Sci ; 103(8): 7377-7391, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32505402

RESUMO

The main objective of this study was to evaluate the efficacy of intrauterine administration of chitosan microparticles (CM) in curing metritis in dairy cows. A secondary objective was to evaluate the effects of metritis treatments on milk yield, survival, and reproductive performance. Cows with a fetid, watery, red-brownish vaginal discharge were diagnosed with metritis. Holstein cows (n = 826) with metritis from 3 dairies located in northern Florida were blocked by parity (primiparous or multiparous) and, within each block, randomly assigned to one of 3 treatments: CM (n = 276) = intrauterine infusion of 24 g of CM dissolved in 40 mL of sterile distilled water at the time of metritis diagnosis (d 0), 2 (d 2), and 4 (d 4) d later; ceftiofur (CEF; n = 275) = subcutaneous injection of 6.6 mg/kg ceftiofur crystalline-free acid in the base of the ear at d 0 and d 3; Control (CON; n = 275) = no treatment applied at metritis diagnosis. All groups could receive escape therapy if condition worsened. Cure was considered when vaginal discharge became mucoid and not fetid. A group of nonmetritic (NMET; n = 2,436) cows was used for comparison. Data were analyzed by generalized linear mixed and Cox's proportional hazard models. Cows in CM and CON had lesser risk of metritis cure on d 12 than cows in CEF (58.6 ± 5.0 vs. 61.9 ± 4.9% vs. 77.9 ± 3.9, respectively). The proportion of cows culled within 60 days in milk (DIM) was greater for cows in CM than for cows in CEF and CON (21.5 ± 2.7 vs. 9.7 ± 1.9 vs. 11.3 ± 2.0%, respectively). Treatment did not affect rectal temperature or plasma nonesterified fatty acids, ß-hydroxybutyrate, and haptoglobin concentrations. Milk yield in the first 60 DIM differed for all treatments, and it was lowest for CM (35.8 ± 0.3 kg/d), followed by CON (36.8 ± 0.3 kg/d) and CEF (37.9 ± 0.3 kg/d). The hazard of pregnancy up to 300 DIM was lesser for CM than CEF (hazard ratio = 0.62; 95% CI: 0.50-0.76), for CM than CON (hazard ratio = 0.77; 95% CI: 0.62-0.95) and for CON than CEF (hazard ratio = 0.80; 95% CI: 0.65-0.99). Culling was greater, and milk yield and fertility were lesser for CEF than NMET. In summary, CM did not improve the cure of metritis, and was detrimental to milk yield, survival, and fertility compared with CON. In contrast, CEF increased the cure of metritis, milk yield, and fertility compared with CM and CON. Finally, the negative effects of metritis on milk yield culling and fertility could not be completely reversed by CEF.


Assuntos
Doenças dos Bovinos/tratamento farmacológico , Quitosana/uso terapêutico , Endometrite/veterinária , Ácido 3-Hidroxibutírico/sangue , Animais , Antibacterianos/uso terapêutico , Bovinos , Cefalosporinas/uso terapêutico , Quitosana/química , Endometrite/tratamento farmacológico , Ácidos Graxos não Esterificados/sangue , Feminino , Fertilidade/efeitos dos fármacos , Florida , Lactação , Leite , Paridade , Tamanho da Partícula , Gravidez , Reprodução
13.
Ir J Med Sci ; 189(4): 1343-1350, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32405923

RESUMO

BACKGROUND: Tissue conditioners are suitable places for colonization of microorganisms. A combination of tissue conditioners with antibacterial and antifungal materials inhibits the growth of microorganisms. AIMS: Here, we aimed to investigate the antibacterial and antifungal effects of silver (Ag), zinc oxide (ZnO), and chitosan nanoparticles on tissue conditioners in complete dentures. METHODS: The growth of four microorganisms in six different concentrations of Ag, ZnO, and chitosan nanoparticles was investigated after 24 and 48 h. Nanoparticles were synthesized using optical sequestration and approved by scanning electron microscope, x-ray diffraction, and infrared (FT-IR) methods. Nanoparticles were combined at 0.5, 0.25, and 0.25 ratios (chitosan, Ag, and ZnO, respectively) with 0.625, 1.25, 2.5, 5, 10, and 20 mass percentages. Tissue conditioners with nanoparticles were entered to test tubes containing microorganisms, and the growth rate was measured using the turbidity method by spectrophotometer after 24 and 48 h of incubation at 37 °C. RESULTS: Growth inhibition of Candida albicans occurred at 2.5% concentration. However, the growth inhibition of Streptococcus mutans, Enterococcus faecalis, and Pseudomonas aeruginosa occurred at 5% after both 24 and 48 h. Also, the optimum nanoparticle concentration for Candida albicans was found to be 1.25% for both timings. On the other hand, the optimum nanoparticle concentration for Streptococcus mutans, Enterococcus faecalis, and Pseudomonas aeruginosa was 2.5% for both time scales. CONCLUSIONS: The combination of Ag, ZnO, and chitosan nanoparticles inhibited the growth of fungi and bacteria in tissue conditioners. These nanoparticles inhibited the growth of fungi more effectively than bacteria.


Assuntos
Antibacterianos/uso terapêutico , Antifúngicos/uso terapêutico , Quitosana/uso terapêutico , Prótese Total/microbiologia , Nanopartículas/uso terapêutico , Prata/uso terapêutico , Óxido de Zinco/uso terapêutico , Humanos
14.
Carbohydr Polym ; 236: 116041, 2020 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-32172855

RESUMO

Fucoidan/trimethylchitosan nanoparticles (FUC-TMC-NPs) have the potential to improve the immunostimulating efficiency of anthrax vaccine adsorbed (AVA). FUC-TMC-NPs with positive (+) or negative (-) surface charges were prepared via polyelectrolyte complexation, both charged NP types permitted high viability and presented no cytotoxicity on L929, A549 and JAWS II dendritic cells. Flow cytometry measurements indicated lower (+)-FUC-TMC-NPs internalization levels than (-)-FUC-TMC-NPs, yet produced high levels of pro-inflammatory cytokines IFN-γ, IL12p40, and IL-4. Moreover, fluorescence microscope images proved that both charged NP could deliver drugs into the nucleus. In vivo studies on A/J mice showed that (+)-FUC-TMC-NPs carrying AVA triggered an efficient response with a higher IgG anti-PA antibody titer than AVA with CpG oligodeoxynucleotides, and yielded 100 % protection when challenged with the anthracis spores. Furthermore, PA-specific IgG1 and IgG2a analysis confirmed that (+)-FUC-TMC-NPs strongly stimulated humoral immunity. In conclusion, (+)-FUC-TMC-NP is promising anthrax vaccine adjuvant as an alternative to CpG.


Assuntos
Adjuvantes Imunológicos/uso terapêutico , Vacinas contra Antraz/uso terapêutico , Quitosana/análogos & derivados , Quitosana/uso terapêutico , Nanopartículas/uso terapêutico , Polissacarídeos/uso terapêutico , Células A549 , Adjuvantes Imunológicos/química , Adjuvantes Imunológicos/toxicidade , Animais , Antraz/terapia , Vacinas contra Antraz/imunologia , Bacillus anthracis/imunologia , Quitosana/toxicidade , Citocinas/metabolismo , Feminino , Humanos , Camundongos , Nanopartículas/toxicidade , Oligodesoxirribonucleotídeos/uso terapêutico , Polissacarídeos/química , Polissacarídeos/toxicidade
15.
Carbohydr Polym ; 230: 115710, 2020 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-31887922

RESUMO

It is urgently needed for effective treatments of extensive skin loss, wherein lack of angiogenesis is a major obstacle. In this study, we present a thermosensitive thiolated chitosan (CSSH) hydrogel conjugated with Histatin1 (Hst1) as a wound dressing to study its efficacy in enhancing the cell adhesion, spreading, migration, and angiogenesis. The composite hydrogels with gelation time of 5-7 min, showed a prolonged release of Hst1. Cell culture indicated that the adhesion, spreading, migration and tubule formation of HUVECs were promoted, especially for the Hst1-H group. The in vivo healing evaluation showed that the rate of recovery in Hst1-H group was increased to 84% at day 7, and the CD31 positive cells, vascular endothelial growth factor (VEGF) positive cells and aligned collagen fibers were significantly more than the controlled groups. Therefore, CSSH/Hst1 hydrogel is a promising candidate for wound healing by accelerating cell adhesion, migration and angiogenesis.


Assuntos
Bandagens , Quitosana/uso terapêutico , Histatinas/farmacologia , Hidrogéis/uso terapêutico , Animais , Adesão Celular , Quitosana/química , Liberação Controlada de Fármacos , Células Endoteliais da Veia Umbilical Humana , Humanos , Masculino , Neovascularização Fisiológica/efeitos dos fármacos , Ratos Sprague-Dawley , Cicatrização/efeitos dos fármacos
16.
Carbohydr Polym ; 231: 115744, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31888854

RESUMO

Chitosan with abundant functional groups is regarded as important ingredients for preparing aerogel materials in life science. The biocompatibility and biodegradability of chitosan aerogels, coupled to the variety of chemical functionalities they include, result in them promising carriers for drug delivery. Moreover, chitosan aerogels as drug delivery vehicles can offer improved drug bioavailability and drug loading capacity due to their highly porous network, considerably large specific surface area and polycationic feature. The major focus of this review lies in preparation methods of chitosan aerogels from acidic aqueous solution and chitosan solution in Ionic Liquids (ILs). In addition, chitosan aerogels as drug delivery carriers are introduced in detail and expected to inspire readers to create new kind of drug delivery system based on chitosan aerogels. Finally, growing points and perspectives of chitosan aerogels in drug delivery system are given.


Assuntos
Quitosana/química , Sistemas de Liberação de Medicamentos , Géis/química , Quitosana/síntese química , Quitosana/uso terapêutico , Portadores de Fármacos , Géis/síntese química , Géis/uso terapêutico , Humanos , Porosidade , Água/química
17.
Int J Mol Sci ; 21(2)2020 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-31941068

RESUMO

As a natural polysaccharide, chitosan possesses good biocompatibility, biodegradability and biosafety. Its hydroxyl and amino groups make it an ideal carrier material in the construction of polymer-drug conjugates. In recent years, various synthetic strategies have been used to couple chitosan with active substances to obtain conjugates with diverse structures and unique functions. In particular, chitosan conjugates with antimicrobial activity have shown great application prospects in the fields of medicine, food, and agriculture in recent years. Hence, we will place substantial emphasis on the synthetic approaches for preparing chitosan conjugates and their antimicrobial applications, which are not well summarized. Meanwhile, the challenges, limitations, and prospects of antimicrobial chitosan conjugates are described and discussed.


Assuntos
Anti-Infecciosos , Quitosana , Glicoconjugados , Anti-Infecciosos/síntese química , Anti-Infecciosos/química , Anti-Infecciosos/uso terapêutico , Quitosana/química , Quitosana/uso terapêutico , Glicoconjugados/síntese química , Glicoconjugados/química , Glicoconjugados/uso terapêutico , Humanos
18.
Vet Surg ; 49(4): 758-763, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31916606

RESUMO

OBJECTIVE: To document marked hemorrhage as a complication of inguinal cryptorchidectomy and its successful treatment with a novel chitosan-based hemostatic agent. STUDY DESIGN: Case report. ANIMALS: One healthy 5-year old quarter horse cryptorchid. METHODS: The horse was presented for routine unilateral cryptorchidectomy after prior hemicastration. An inguinal approach was made to the abdomen, and the right external pudendal artery was lacerated at the level of the internal inguinal ring, requiring multiple anesthetic events over a 2-week period in attempts to control hemorrhage. A chitosan-based hemostatic agent was packed into the wound to gain control. RESULTS: Chitosan granules placed in the wound successfully controlled the hemorrhage, whereas the use of gauze packing alone failed. There were no immediate or long-term complications to the chitosan granules; the horse was doing well 18 months postoperatively, and the client was satisfied with the outcome. CONCLUSION: Major hemorrhage was demonstrated from the external pudendal artery and caused difficulties because it occurred deep within the inguinal canal during an inguinal cryptorchidectomy. A chitosan-based hemostatic agent was successfully used to achieve hemostasis. CLINICAL SIGNIFICANCE: The external pudendal artery should be avoided in the medial commissure of the inguinal canal. The use of chitosan-based hemostatic agents warrants further investigation in horses because these products may be useful for controlling major hemorrhage from various causes in equine practice.


Assuntos
Quitosana/uso terapêutico , Criptorquidismo/veterinária , Hemostasia , Hemostáticos/uso terapêutico , Doenças dos Cavalos/cirurgia , Animais , Criptorquidismo/sangue , Criptorquidismo/cirurgia , Doenças dos Cavalos/sangue , Cavalos , Masculino
19.
Int Immunopharmacol ; 78: 105798, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31784403

RESUMO

The objective of the present study was to evaluate the effects of low-molecular-weight chitosan (LMWC) on the growth performance, immune responses and intestinal health of weaned pigs challenged by enterotoxigenic Escherichia coli (ETEC). A total of 32 weaned pigs were randomly allocated to four treatments: non-challenged (fed with basal diet), ETEC-challenged (fed with basal diet) and ETEC-challenged plus 50 or 100 mg/kg LMWC supplementation, respectively. After 11 days feeding, the non-challenged pigs were infused with sterilised Luria-Bertani culture, while the remaining pigs were infused with 2.6 × 1011 colony-forming units of ETEC. At 3 days post-challenge, all pigs were administered d-xylose at 0.1 g/kg body weight. One hour later, blood samples were obtained, and the pigs then euthanised to collect intestinal samples. Data showed that only 100 mg/kg LMWC supplementation attenuated (P < 0.05) the average daily gain reduction caused by ETEC. Furthermore, besides the decreased (P < 0.05) serum tumour necrosis factor-α and immunoglobulin (Ig) G concentrations detected in ETEC-challenged pigs supplemented with LMWC at 50 or 100 mg/kg, the higher dose (100 mg/kg) also decreased (P < 0.05) the serum IgM concentration and increased (P < 0.05) the villus height and villus height-to-crypt depth ratio in both the jejunum and ileum, and the sucrase activity in the ileal mucosa. Moreover, LMWC supplementation (50 or 100 mg/kg) in ETEC-challenged pigs elevated (P < 0.05) the mRNA levels of jejunal mucosal peptide transporter 1 and ileal mucosal peptide transporter 1, divalent metal transporter 1 and zinc transporter 1, and decreased (P < 0.05) the ileal and caecal E. coli abundances, while 100 mg/kg LMWC additionally elevated (P < 0.05) the ileal Bacillus abundance, and caecal and colonic Bifidobacterium abundances. These results suggest that LMWC helps alleviate ETEC-induced growth retardation in weaned pigs, which could be associated with the inhibition of the immune responses and improved intestinal health.


Assuntos
Quitosana/uso terapêutico , Suplementos Nutricionais , Escherichia coli Enterotoxigênica , Infecções por Escherichia coli/dietoterapia , Transtornos do Crescimento/dietoterapia , Animais , Quitosana/química , Citocinas/sangue , Infecções por Escherichia coli/sangue , Infecções por Escherichia coli/complicações , Infecções por Escherichia coli/patologia , Transtornos do Crescimento/sangue , Transtornos do Crescimento/etiologia , Transtornos do Crescimento/patologia , Imunoglobulinas/sangue , Intestinos/efeitos dos fármacos , Intestinos/enzimologia , Intestinos/patologia , Lactase/sangue , Peso Molecular , Sacarase/sangue , Suínos , Desmame , alfa-Glucosidases/sangue
20.
Curr Med Chem ; 27(30): 5037-5055, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31309881

RESUMO

Chitosan oligosaccharides (COS), hydrolysed products of chitosan, are low-molecular weight polymers with a positive charge and good biocompatibility. COS have recently been reported to possess various biological activities, including hypoglycaemic, hypolipidaemic, antioxidantantioxidant, immune regulation, anti-inflammatory, antitumour, antibacterial, and tissue engineering activities, exhibiting extensive application prospects. Currently, the biological processes and mechanisms of COS are attractive topics of study, ranging from the genetic, molecular and protein levels. This article reviews the recent discoveries about COS, especially in metabolic regulation, immune function and tissue repair, providing important insights into their multiple biological activities, medical benefits, and therapeutic mechanisms.


Assuntos
Quitosana , Oligossacarídeos , Anti-Inflamatórios , Quitosana/uso terapêutico , Peso Molecular , Oligossacarídeos/uso terapêutico
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