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1.
J Refract Surg ; 37(9): 631-635, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34506235

RESUMO

PURPOSE: To evaluate corneal stiffening in porcine eyes induced by corneal cross-linking (CXL) using riboflavin dissolved in either aqueous dextran or hydroxypropyl methylcellulose (HPMC) solution. METHODS: Fifty-one porcine corneas were divided into three groups of 17 each. After deepithelialization, the first (Dresden) group was treated for 30 minutes with 0.1% riboflavin (riboflavin-5-monophosphate in 0.9% NaCl) dissolved in hypertonic 20% dextran and the second (HPMC) group for 30 minutes with isotonic solution containing 0.1% riboflavin and 1.1% HPMC. Thereafter, corneas of both groups were irradiated using 5.4 J/cm2 (irradiance of 9 mW/cm2 for 10 minutes; 10*9). After CXL, all corneas were kept in an isotonic 16% dextran bath for 2 hours to obtain an equal hydration state. The third group served as the control group. Stress-strain measurements were performed on 5-mm-wide strips. Corneal thickness was monitored throughout the entire course of the experiments. RESULTS: The required stress for a 10% strain was increased by 83% in the Dresden group and 35% in the HPMC group compared to the control group. Resultant Young's modulus (at 10% strain) was 2.53 ± 0.73, 1.87 ± 0.50, and 1.47 ± 0.44 Pa for the Dresden, HPMC, and control groups, respectively. The differences between the Dresden and HPMC groups (P = .006), the Dresden and control groups (P < .001), and the HPMC and control groups (P = .014) were statistically significant. Pachymetry measurements showed a significantly increased corneal thickness after application of HPMC compared with the Dresden group (P = .002) and control group (P = .041). CONCLUSIONS: The biomechanical stiffening of the cornea by CXL can be achieved using dextran- and HPMC-based riboflavin solutions in porcine corneas with an application time of 30 minutes. Dextran-based riboflavin solutions seem to induce a slightly stronger biomechanical response in this setting. HPMC solutions induce less thinning than dextran solutions. [J Refract Surg. 2021;37(9):631-635.].


Assuntos
Substância Própria , Dextranos , Animais , Fenômenos Biomecânicos , Colágeno , Córnea , Reagentes para Ligações Cruzadas , Derivados da Hipromelose , Fármacos Fotossensibilizantes , Riboflavina/farmacologia , Suínos , Raios Ultravioleta
2.
J Refract Surg ; 37(9): 623-630, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34506244

RESUMO

PURPOSE: To compare the clinical and tomographic properties of adult patients with keratoconus treated with accelerated corneal cross-linking (A-CXL) versus accelerated contact lens-assisted corneal cross-linking (A-CACXL). METHODS: Patients who underwent A-CXL and A-CACXL due to progressive keratoconus were enrolled from January 2015 to January 2018 in this retrospective case-control study. The treatment group (minimum corneal thickness of less than 400 µm after epithelium removal; 30 patients, 30 eyes) was treated with A-CACXL; the control group (minimum corneal thickness of 400 µm or greater, 32 patients, 32 eyes) was treated with A-CXL. Assessments occurred before treatment and 12 months postoperatively. Demographic, clinical, and tomographic data were obtained from outpatient clinic reports. RESULTS: Significant improvement in visual acuity was evident at 12-month follow-up for the control group in uncorrected distance visual acuity (0.62 ± 0.42 vs 0.43 ± 0.31 logMAR, P = .01) and the treatment group in corrected distance visual acuity (0.51 ± 0.30 vs 0.40 ± 0.49 logMAR, P = .03). Progression of keratoconus was halted at similar rates for both groups (76.7% treatment, 84.4% control, P = .21). Mean minimum corneal thickness showed minor but significant thinning at the 12-month follow-up visit compared to baseline (control group = 463 ± 31 vs 450 ± 35 µm, P > .01; treatment group = 398 ± 32 vs 388 ± 41 µm, P = .02). CONCLUSIONS: A-CACXL halted keratoconus progression in 76.7% of eyes and achieved regression in 33.3% of eyes, with rates comparable to A-CXL. Visual outcomes improved for both groups, with similar keratometry changes. A-CACXL is an effective and safe option for patients with keratoconus and thin corneas, with results similar to A-CXL treatment in patients with a minimum corneal thickness of 400 µm or greater. [J Refract Surg. 2021;37(9):623-630.].


Assuntos
Lentes de Contato , Ceratocone , Fotoquimioterapia , Adulto , Estudos de Casos e Controles , Colágeno/uso terapêutico , Topografia da Córnea , Reagentes para Ligações Cruzadas/uso terapêutico , Seguimentos , Humanos , Ceratocone/tratamento farmacológico , Fármacos Fotossensibilizantes/uso terapêutico , Estudos Retrospectivos , Riboflavina/uso terapêutico , Raios Ultravioleta
3.
Cesk Slov Oftalmol ; 77(4): 184-189, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34507494

RESUMO

AIM: To evaluate the effect of crosslinking (CXL) therapy on the change in the quality of visual acuity and the change in the topographic properties of the cornea - curvature, pachymetry, and change of astigmatism, coma abberation and CLMIaa (Cone Localisation and Magnitude Index). METHODS: A retrospective analytical study included 29 eyes of 24 patients who had progressed in the last 12 months and were suitable candidates for CXL surgery. The monitored parameters were the steepest, flatest and mean anterior instantaneous curvature (AICS, AICF, AICM) and the steepest, flatest and mean posterior instantaneous curvature (PICS, PICF, PICM) of the cornea, corneal thickness in the centre of the cornea (PACHC) and in the thinnest point of the cornea (PACHT), corneal astigmatism (ASTIG). coma (COMA), Cone Localization and Magnitude Index (CLMIaa) and uncorrected distance visual acuity (UDVA) with corrected distance visual acuity (CDVA). Data were analysed before surgery and 12 months after surgery. The AIC, COMA, CLMIaa and ASTIG parameters were analysed by paired t test. As the parameters of UDVA, CDVA, PIC and PACH did not meet the conditions of normal distribution, the Wilcoxon test was used to investigate the change in these parameters after CXL. RESULTS: Twelve months after the procedure, we recorded an improvement in UDVA (p = 0.371) and CDVA (p = 0.825), an increase in PICS, PICF and PICM (p = 0.902; p = 0.87 and p = 0.555), a decrease in PACHCC (p = 0.294) and a decrease in CLMIaa (p = 0.113) that did not reach statistical significance. The decrease in PACHT (p = 0.027), decrease in COMA (p = 0.037) and decrease in anterior corneal curvature of AICS, AICF and AICM were statistically significant (p = 0.019; p = 0.010 and p = 0.005). The decrease in the value of astigmatism did not show statistical significance, as p = 0.297. CONCLUSION: CXL corneal therapy has been shown to be an effective method to stabilize the cornea in progressive keratoconus, and to improve the higher order of coma. This contributes to the possible improvement of UDVA and CDVA.


Assuntos
Ceratocone , Colágeno , Córnea , Substância Própria , Topografia da Córnea , Reagentes para Ligações Cruzadas , Humanos , Ceratocone/tratamento farmacológico , Fármacos Fotossensibilizantes/uso terapêutico , Estudos Retrospectivos , Riboflavina/uso terapêutico , Acuidade Visual
4.
Acta Cir Bras ; 36(7): e360706, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34495141

RESUMO

PURPOSE: To compare tissue inflammatory response, foreign body reaction, fibroplasia, and proportion of type I/III collagen between closure of abdominal wall aponeurosis using polyglactin suture and intraperitoneal implant of polypropylene, polypropylene/polyglecaprone, and polyester/porcine collagen meshes to repair defects in the abdominal wall of rats. METHODS: Forty Wistar rats were placed in four groups, ten animals each, for the intraperitoneal implant of polypropylene, polypropylene/polyglecaprone, and polyester/porcine collagen meshes or suture with polyglactin (sham) after creation of defect in the abdominal wall. Twenty-one days later, histological analysis was performed after staining with hematoxylin-eosin and picrosirius red. RESULTS: The groups with meshes had a higher inflammation score (p < 0.05) and higher number of gigantocytes (p < 0.05) than the sham group, which had a better fibroplasia with a higher proportion of type I/III collagen than the tissue separating meshes (p < 0.05). There were no statistically significant differences between the three groups with meshes. CONCLUSIONS: The intraperitoneal implant of polypropylene/polyglecaprone and polyester/porcine collagen meshes determined a more intense tissue inflammatory response with exuberant foreign body reaction, immature fibroplasia and low tissue proportion of type I/III collagen compared to suture with polyglactin of abdominal aponeurosis. However, there were no significant differences in relation to the polypropylene mesh group.


Assuntos
Parede Abdominal , Polipropilenos , Parede Abdominal/cirurgia , Animais , Aponeurose , Colágeno , Reação a Corpo Estranho/etiologia , Teste de Materiais , Poliglactina 910/efeitos adversos , Polipropilenos/efeitos adversos , Ratos , Ratos Wistar , Telas Cirúrgicas/efeitos adversos , Suturas , Suínos
5.
Mater Sci Eng C Mater Biol Appl ; 128: 112295, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34474846

RESUMO

It is of great significance to develop osteoinductive artificial scaffold for bone repair and regeneration. We constructed a biomimetic apatite interface on electrospun polycaprolactone fibers by combining layer-by-layer (LbL) nanocoating with mineralization to fabricate an osteoinductive artificial scaffold. After polydopamine modification, cationic type-І collagen and anionic chondroitin sulfate were sequentially adsorbed on the fiber surface. The fibers coated with the multilayer components served as the precursor matrix to induce apatite deposition. By adjusting the number of the layers and duration of mineralization, the nanoscale morphology of composite fibers was optimized. When ten bilayers of the collagen and chondroitin sulfate were deposited onto the fibers followed by one day-mineralization, the obtained polycaprolactone-apatite composite scaffolds significantly promoted the adhesion, proliferation, and osteogenic differentiation of MC3T3-E1 cells. In a subcutaneous implantation in mice, this composite fiber membrane enhanced in vivo ectopic osteogenesis. Our nano-architectural scaffolds were able to mimic the composition and structure of the bone matrix to a certain extent, holding great potential for bone repair and regeneration.


Assuntos
Sulfatos de Condroitina , Osteogênese , Animais , Regeneração Óssea , Diferenciação Celular , Colágeno , Camundongos , Tecidos Suporte
6.
Mater Sci Eng C Mater Biol Appl ; 128: 112321, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34474872

RESUMO

The topographic surface conditions of scaffolds can regulate cellular behaviours, such as by stimulating cellular migration and morphological changes to wound sites and have the potential to promote tissue regeneration. In this research, four types of engineered topographic surfaces, including arrays of hemisphere, pyramid, semi-cylinder, and triangle prism microstructures, were patterned on silicon moulds using microfabrication processes. The microstructural patterns were transferred onto the surface of polycaprolactone membranes and nanofibrous scaffolds by combining with the moulding approach and electrospinning technique, respectively. In vitro experimental results demonstrated that the triangular microstructural nanofibre provided a strong guiding performance to the filopodia of cultured C2C12 myoblast cells, thus inducing cellular elongation and alignment in the longitudinal direction and forming an elongated cell morphology. The cultured cells rapidly transitioned into an elongated morphology at an aspect ratio of 17.33 after 24 h of incubation, with 70% of the cell elongates aligning with the direction of triangular microstructural patterns. The cells cultured on the triangular microstructural nanofibre elongated four-fold compared with those in the flat nanofibre scaffold. Moreover, an in vivo study showed that wounds treated with the triangular microstructural nanofibre scaffold achieved 95.04% wound closure after 14 days and completed the reepithelialisation with an ordered collagen arrangement. Therefore, we believe that the engineered triangular nanofibrous scaffold may accelerate tissue regeneration and has potential for wound healing applications.


Assuntos
Nanofibras , Células Cultivadas , Colágeno , Poliésteres , Engenharia Tecidual , Tecidos Suporte , Cicatrização
7.
Mater Sci Eng C Mater Biol Appl ; 128: 112328, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34474879

RESUMO

Hydrogel-based drug delivery systems have emerged as a promising platform for chronic tissue defects owing to their inherent ability to inhibit pathogenic infection and accelerate rapid tissue regeneration. Here, we fabricated a stable bio-hybrid hydrogel system comprising collagen, aminated xanthan gum, bio-capped silver nanoparticles and melatonin with antimicrobial, antioxidant and anti-inflammatory properties. Highly colloidal bio-capped silver nanoparticles were synthesized using collagen as a reducing cum stabilizing agent for the first time while aminated xanthan gum was synthesized using ethylenediamine treatment on xanthan gum. The synthesized bio-hybrid hydrogel exhibits better gelation, surface morphology, rheology and degelation properties. In vitro assessment of bio-hybrid hydrogel demonstrates excellent bactericidal efficiency against both common wound and multidrug-resistant pathogens and biocompatibility properties. In vivo animal studies demonstrate rapid tissue regeneration, collagen deposition and angiogenesis at the wound site predominantly due to the synergistic effect of silver nanoparticles and melatonin in the hydrogel. This study paves the way for developing biologically functional bio-nano hydrogel systems for promoting effective care for various ailments, including infected chronic wounds.


Assuntos
Melatonina , Nanopartículas Metálicas , Animais , Antibacterianos/farmacologia , Colágeno , Hidrogéis , Melatonina/farmacologia , Prata/farmacologia
8.
Mater Sci Eng C Mater Biol Appl ; 128: 112340, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34474890

RESUMO

Mechanical robustness is an essential consideration in the development of hydrogel platforms for bone regeneration, and despite significant advances in the field of injectable hydrogels, many fail in this regard. Inspired by the mechanical properties of carboxylated single wall carbon nanotubes (COOH-SWCNTs) and the biological advantages of natural polymers, COOH-SWCNTs were integrated into chitosan and collagen to formulate mechanically robust, injectable and thermoresponsive hydrogels with interconnected molecular structure for load-bearing applications. This study presents a complete characterisation of the structural and biological properties, and mechanism of gelation of these novel formulated hydrogels. Results demonstrate that ß-glycerophosphate (ß-GP) and temperature play important roles in attaining gelation at physiological conditions, and the integration with COOH-SWCNTs significantly changed the structural morphology of the hydrogels to a more porous and aligned network. This led to a crystalline structure and significantly increased the mechanical strength of the hydrogels from kPa to MPa, which is closer to the mechanical strength of the bone. Moreover, increased osteoblast proliferation and rapid adsorption of hydroxyapatite on the surface of the hydrogels indicates increased bioactivity with addition of COOH-SWCNTs. Therefore, these nano-engineered hydrogels are expected to have wide utility in the area of bone tissue engineering and regenerative medicine.


Assuntos
Quitosana , Nanotubos de Carbono , Colágeno , Hidrogéis , Engenharia Tecidual
9.
Anticancer Res ; 41(9): 4313-4319, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34475051

RESUMO

BACKGROUND/AIM: In order to produce an animal model for oral mucositis induced by anticancer drugs, it is necessary to maintain an immunosuppressive state. We determined the optimal dose and frequency of 5-fluorouracil for a model mouse production. In addition, we used this model to investigate the effect of GGsTop® gelation on the therapeutic effect of oral mucositis. MATERIALS AND METHODS: Changes in body weight and white blood cell count were measured to determine the optimal dosing schedule. The therapeutic effect of GGsTop® gel using chitosan was evaluated by observing changes in the ulcer area for three weeks and measuring collagen and glutathione concentrations in oral mucosal tissue. RESULTS: The optimal dose and frequency of 5-fluorouracil were found to be 50 mg/kg every four days. It was revealed that the therapeutic effect of GGsTop® was enhanced by gelation. CONCLUSION: GGsTop® gel is suggested to be a promising formulation for the treatment of oral mucositis.


Assuntos
Aminobutiratos/administração & dosagem , Antimetabólitos Antineoplásicos/efeitos adversos , Fluoruracila/efeitos adversos , Leucócitos/efeitos dos fármacos , Organofosfonatos/administração & dosagem , Estomatite/tratamento farmacológico , Aminobutiratos/farmacologia , Animais , Antimetabólitos Antineoplásicos/administração & dosagem , Peso Corporal/efeitos dos fármacos , Colágeno/metabolismo , Modelos Animais de Doenças , Cálculos da Dosagem de Medicamento , Fluoruracila/administração & dosagem , Géis , Glutationa/metabolismo , Masculino , Camundongos , Organofosfonatos/farmacologia , Estomatite/induzido quimicamente , Estomatite/metabolismo
10.
Int J Mol Sci ; 22(16)2021 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-34445538

RESUMO

Decellularized tissues are biocompatible materials that engraft well, but the age of their source has not been explored for clinical translation. Advanced glycation end products (AGEs) are chemical cross-links that accrue on skeletal muscle collagen in old age, stiffening the matrix and increasing inflammation. Whether decellularized biomaterials derived from aged muscle would suffer from increased AGE collagen cross-links is unknown. We characterized gastrocnemii of 1-, 2-, and 20-month-old C57BL/6J mice before and after decellularization to determine age-dependent changes to collagen stiffness and AGE cross-linking. Total and soluble collagen was measured to assess if age-dependent increases in collagen and cross-linking persisted in decellularized muscle matrix (DMM). Stiffness of aged DMM was determined using atomic force microscopy. AGE levels and the effect of an AGE cross-link breaker, ALT-711, were tested in DMM samples. Our results show that age-dependent increases in collagen amount, cross-linking, and general stiffness were observed in DMM. Notably, we measured increased AGE-specific cross-links within old muscle, and observed that old DMM retained AGE cross-links using ALT-711 to reduce AGE levels. In conclusion, deleterious age-dependent modifications to collagen are present in DMM from old muscle, implying that age matters when sourcing skeletal muscle extracellular matrix as a biomaterial.


Assuntos
Envelhecimento/metabolismo , Colágeno/metabolismo , Matriz Extracelular/metabolismo , Produtos Finais de Glicação Avançada/metabolismo , Músculo Esquelético/metabolismo , Envelhecimento/patologia , Animais , Matriz Extracelular/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Músculo Esquelético/patologia
11.
Nat Commun ; 12(1): 5059, 2021 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-34429413

RESUMO

With the current interest in cultured meat, mammalian cell-based meat has mostly been unstructured. There is thus still a high demand for artificial steak-like meat. We demonstrate in vitro construction of engineered steak-like tissue assembled of three types of bovine cell fibers (muscle, fat, and vessel). Because actual meat is an aligned assembly of the fibers connected to the tendon for the actions of contraction and relaxation, tendon-gel integrated bioprinting was developed to construct tendon-like gels. In this study, a total of 72 fibers comprising 42 muscles, 28 adipose tissues, and 2 blood capillaries were constructed by tendon-gel integrated bioprinting and manually assembled to fabricate steak-like meat with a diameter of 5 mm and a length of 10 mm inspired by a meat cut. The developed tendon-gel integrated bioprinting here could be a promising technology for the fabrication of the desired types of steak-like cultured meats.


Assuntos
Bioimpressão/métodos , Géis , Carne , Tendões , Animais , Bovinos , Técnicas de Cultura de Células , Colágeno , Células Endoteliais , Músculos/citologia , Músculos/fisiologia , Impressão Tridimensional , Células-Tronco , Tendões/citologia , Engenharia Tecidual
12.
In Vivo ; 35(5): 2541-2549, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34410941

RESUMO

BACKGROUND/AIM: The aim of this study was the conception, production, material analysis and cytocompatibility analysis of a new collagen foam for medical applications. MATERIALS AND METHODS: After the innovative production of various collagen sponges from bovine sources, the foams were analyzed ex vivo in terms of their structure (including pore size) and in vitro in terms of cytocompatibility according to EN ISO 10993-5/-12. In vitro, the collagen foams were compared with the established soft and hard tissue materials cerabone and Jason membrane (both botiss biomaterials GmbH, Zossen, Germany). RESULTS: Collagen foams with different compositions were successfully produced from bovine sources. Ex vivo, the foams showed a stable and long-lasting primary structure quality with a bubble area of 1,000 to 2,000 µm2 In vitro, all foams showed sufficient cytocompatibility. CONCLUSION: Collagen sponges represent a promising material for hard and soft tissue regeneration. Future studies could focus on integrating and investigating different additives in the foams.


Assuntos
Materiais Biocompatíveis , Colágeno , Animais , Bovinos , Alemanha , Cicatrização
13.
Vestn Oftalmol ; 137(4): 110-115, 2021.
Artigo em Russo | MEDLINE | ID: mdl-34410065

RESUMO

The review highlights the features of molecular, morphological and anatomical organization of the vitreous body in normal human eyes and in eyes with elongated anterior-posterior axis. The molecular structure of the vitreous consists of various types of collagen, glycosaminoglycans, glycoproteins and proteoglycans. The lowest concentration of collagen fibrils is in the central vitreous, so the structural changes of vitreous gel associated with attenuation of the vitreous body happen there much earlier and to a greater degree. Increased aggregation of collagen fibrils with age casuses an increase of liquid fractions of the vitreous with a concomitant decrease in gel volume. Similar processes occur earlier in eyes with axial myopia. Destructive processes in myopia increase progressively with axial elongation. As a result of vitreous collapse, vitreoretinal adhesion weakens and posterior vitreous detachment occurs.


Assuntos
Miopia , Descolamento do Vítreo , Colágeno , Humanos , Corpo Vítreo , Descolamento do Vítreo/diagnóstico
14.
BMC Res Notes ; 14(1): 310, 2021 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-34389056

RESUMO

OBJECTIVE: The spheroid model provides a physiological platform to study cancer cell biology and drug sensitivity. Usage of bovine collagen I for spheroid assays is costly especially when experiments are conducted in 24-well plates, as high volume of bovine collagen I is needed. The aim of the study was to downsize spheroid assays to a microfluidic 3D cell culture chip and compare the growth, invasion and response to drug/compound of spheroids embedded in the 3D chip to spheroids embedded in 24-well plates. RESULTS: Spheroids generated from nasopharyngeal carcinoma cell line HK-1 continuously grew and invaded into collagen matrix in a 24-well plate. Similar observations were noticed with spheroids embedded in the 3D chip. Large spheroids in both 24-well plate and the 3D chip disintegrated and invaded into the collagen matrix. Preliminary drug sensitivity assays showed that the growth and invasion of spheroids were inhibited when spheroids were treated with combination of cisplatin and paynantheine at high concentrations, in a 24-well plate. Comparable findings were obtained when spheroids were treated with the same drug combination in the 3D chip. Moving forward, spheroid assays could be performed in the 3D chip in a more high-throughput manner with minimal time and cost.


Assuntos
Técnicas de Cultura de Células , Esferoides Celulares , Animais , Bioensaio , Bovinos , Linhagem Celular , Colágeno , Humanos
15.
J Contemp Dent Pract ; 22(6): 680-685, 2021 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-34393127

RESUMO

AIM: The aim of the study is (a) To use collagen as a pulpotomy material in comparison with the gold standard formocresol-based pulpotomy, (b) to assess the clinical and radiographic success rate of formocresol pulpotomy and collagen-based pulpotomy, and (c) to compare the success rate of formocresol-based pulpotomy and collagen-based pulpotomy over a definitive interval of time. MATERIALS AND METHODS: Totally 30 primary first or second molars indicated for pulpotomy after confirming with the operative diagnosis were taken as samples for this study. This split-mouth technique consists of two groups: Group 1-formocresol pulpotomy (n = 15), and group 2-collagen-based pulpotomy (n = 15). Both the procedures were done in the same patient on regular appointments. Pre- and postoperative radiographs were taken. The children were recalled for clinical and radiographic follow-up at 2, 4, and 6 months. The success of the procedure was assessed based on clinical signs (pain, tenderness to percussion, abscess, swelling, fistula, and pathologic mobility) and radiographic findings (radicular radiolucency, internal and external root resorption, periodontal ligament (PDL) space widening, and furcation radiolucency). The Chi-square test was used to compare the differences between the groups. RESULT: The overall success rate for formocresol pulpotomy (n = 15) was 14, 13, and 10 for the second-, fourth-, and sixth-month review period, respectively. For collagen pulpotomy group (n = 15), the overall success rate was 14, 14, and 14 for the second-, fourth-, and sixth-month review period, respectively. The obtained data from the overall success rate were subjected to statistical analysis, and chi-square test was used. The p-value less than 0.1 was considered a statistically significant result. The chi-square value for the fourth- and sixth-month review was 0.37 and 3.33, respectively. CONCLUSION: Statistically significant value was obtained from the sixth-month review period (p <0.1), which describes that the overall success rate was better for the collagen pulpotomy group when compared with the formocresol pulpotomy group. CLINICAL SIGNIFICANCE: Collagen had proven to be a very good alternative for formocresol, its biocompatibility, and regenerative efficiency and is a benchmark for a better clinical success rate in dentistry. However, its implication in pulpotomy should be subjected to further comparative research study on mineral trioxide aggregate (MTA), Biodentine, etc. Keywords: Collagen-based pulpotomy, Formocresol-based pulpotomy.


Assuntos
Formocresóis , Pulpotomia , Compostos de Alumínio , Compostos de Cálcio , Criança , Colágeno , Combinação de Medicamentos , Humanos , Dente Molar/diagnóstico por imagem , Dente Molar/cirurgia , Óxidos , Silicatos , Dente Decíduo
16.
J Chem Phys ; 155(7): 075102, 2021 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-34418922

RESUMO

In this paper, we have studied the vibrational spectral features for the collagen triple helix using a dispersion corrected hybrid density functional theory (DFT-D) approach. The protein is simulated by an infinite extended polymer both in the gas phase and in a water micro-solvated environment. We have adopted proline-rich collagen models in line with the high content of proline in natural collagens. Our scaled harmonic vibrational spectra are in very good agreement with the experiments and allow for the peak assignment of the collagen amide I and III bands, supporting or questioning the experimental interpretation by means of vibrational normal modes analysis. Furthermore, we demonstrated that IR spectroscopy in the THz region can detect the small variations inherent to the triple helix helicity (10/3 over 7/2), thus elucidating the packing state of the collagen. So far, identifying the collagen helicity is only possible by means of crystal x-ray diffraction.


Assuntos
Amidas/química , Colágeno/química , Teoria da Densidade Funcional , Modelos Moleculares , Prolina/química , Conformação Proteica em alfa-Hélice , Solventes/química , Vibração
17.
In Vivo ; 35(5): 2697-2702, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34410958

RESUMO

BACKGROUND/AIM: We aimed to evaluate the safety and efficacy of sealing primary upper gastrointestinal (GI) perforations with a collagen patch coated with fibrin glue (Tachosil®). MATERIALS AND METHODS: Thirty New Zealand rabbits were used in this study. An iatrogenic gastric perforation was created, and primary repair was performed on the control group. Tachosil®, without suturing the deficit, was used in the intervention group. RESULTS: Leakage was observed in 3 (20%) and 2 rabbits (13.3%) in the control and intervention group, respectively; however, the difference was not statistically significant (p=0.62). Moreover, adhesions formed in 10/15 and all rabbits in the intervention and control group, respectively (p=0.014); however, based on the Zuhlke adhesion's classification, there was no statistically significant difference between the two groups. CONCLUSION: A collagen patch coated with fibrin glue is not a replacement but can be considered a safe option for the reinforcement of suturing, preventing leakages in the upper GI tract.


Assuntos
Adesivo Tecidual de Fibrina , Trato Gastrointestinal Superior , Animais , Colágeno , Coelhos , Aderências Teciduais
18.
Adv Exp Med Biol ; 1331: 193-202, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34453299

RESUMO

Alzheimer's disease (AD) is a severe neurodegenerative disorder of the brain characterized by extracellular beta-amyloid plaques, intraneuronal tau inclusions, vascular impairment, inflammation, neurodegeneration, and memory loss. Acetylcholine is the most important neurotransmitter for memory, and cholinergic neurons selectively degenerate in AD, and a loss of acetylcholine directly correlates with cognitive decline. Nerve growth factor (NGF) is the most potent growth factor to support the survival of these cholinergic neurons. Thus, researchers are interested to deliver NGF directly into the brain to the cholinergic neurons. As the brain is isolated by the blood-brain barrier, the large protein NGF cannot easily pass into the brain, and peripheral administration of NGF also causes severe side effects. Blood cells may represent a potent therapeutic strategy to deliver NGF into the brain. Monocytes can be isolated and loaded with NGF and may transmigrate into the brain. As monocytes are precursors of microglia, they may differentiate and release NGF but also phagocyte and eliminate toxic plaques. Platelets are small anuclear cells and become rapidly activated during vascular lesions, and they may migrate to lesion sites and repair blood vessels and also eliminate toxic beta-amyloid depositions in vessels. In order to guarantee a stable and slow release, the use of biomaterials is of interest, especially collagen hydrogels that may be useful to protect these transmigrating blood cells. In this review, I summarize advantages and challenges of using transmigrating cells to deliver NGF directly into the brain.


Assuntos
Doença de Alzheimer , Doença de Alzheimer/tratamento farmacológico , Colágeno , Humanos , Hidrogéis , Monócitos , Fator de Crescimento Neural
19.
Am J Sports Med ; 49(11): 2924-2932, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34343026

RESUMO

BACKGROUND: Patellar tendinopathy is a common cause of limitations in daily life activities in young and/or active people. The patellar tendon consists of a complex of collagen fibers; therefore, collagen could be used as a scaffold in the treatment of patellar tendinopathy. PURPOSE: To evaluate the healing capacity of injected atelocollagen as a treatment scaffold for patellar tendon defect and, hence, its potential for the treatment of patellar tendinopathy. STUDY DESIGN: Controlled laboratory study. METHODS: After receiving a full-thickness patellar tendon defect, 24 New Zealand White rabbits were divided into a control group (without treatment) and an experimental group that received an atelocollagen injection into the defect. Six rabbits from each group were subsequently used for either histologic scoring or biomechanical testing. The Mann-Whitney U test was used to compare histologic evaluation scores and load to failure between the 2 groups. Statistical significance was set at P < .05. RESULTS: The experimental group showed excellent repair of the damaged patellar tendon and good remodeling of the defective area. In contrast, the control group showed defective healing with loose, irregular matrix fibers and adipose tissue formation. A statistically significant difference was found between the 2 groups in both histologic scores and biomechanical tests at postoperative week 12. CONCLUSION: Injection of atelocollagen significantly improved the regeneration of damaged patellar tendons. CLINICAL RELEVANCE: Atelocollagen gel injections could be used to treat patellar tendinopathy in outpatient clinic settings.


Assuntos
Ligamento Patelar , Tendinopatia , Animais , Colágeno , Patela , Ligamento Patelar/cirurgia , Coelhos
20.
Clin Immunol ; 230: 108813, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34333094

RESUMO

Cigarette smoking has been implicated in the pathogenesis of seropositive rheumatoid arthritis (RA), as well as RA-associated lung disease. Fibrotic interstitial lung disease as well as emphysema occur in RA and cause substantial morbidity. We used arthritis-susceptible HLA-DQ8 transgenic mice to generate RA-associated lung disease. Mice were exposed to cigarette smoke (CS) prior to induction of arthritis, and subsequently injected with a low dose of bleomycin intra-tracheally to induce lung injury. Exposure of arthritic mice to both CS and bleomycin led to a significant reduction in lung compliance consistent with development of diffuse lung disease. Morphologic evaluation of the lung demonstrated areas of emphysematous change and co-existent fibrosis, consistent with a combined pattern of fibrosis and emphysema. These changes were accompanied by inflammatory cell infiltration and upregulation of fibrosis-associated genes. This humanized mouse model can serve as a valuable research tool to understand the pathogenesis of RA associated lung disease.


Assuntos
Artrite Reumatoide/complicações , Doenças Pulmonares Intersticiais/etiologia , Animais , Artrite Reumatoide/etiologia , Bleomicina/toxicidade , Fumar Cigarros/efeitos adversos , Colágeno/metabolismo , Modelos Animais de Doenças , Feminino , Expressão Gênica , Humanos , Pulmão/metabolismo , Pulmão/patologia , Complacência Pulmonar/efeitos dos fármacos , Doenças Pulmonares Intersticiais/patologia , Masculino , Camundongos , Camundongos Transgênicos , Enfisema Pulmonar/etiologia , Fibrose Pulmonar/etiologia
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