Efficiency analysis of commercial polymeric membranes for bone regeneration in rat cranial defects

Purpose: To evaluate the in vivo efficiency of commercial polymeric membranes for guided bone regeneration. Methods: Rat calvarial critical size defects was treated with LuminaCoat (LC), Surgitime PTFE (SP), GenDerm (GD), Pratix (PR), Techgraft (TG) or control (C-) and histomorphometric analysis determined the percentage of new bone, connective tissue and biomaterial at 1 or 3 months. Statistical analysis used ANOVA with Tukey's post-test for means at same experimental time and the paired Student's t test between the two periods, considering p < 0.05. Results: New bone at 1 month was higher for SP, TG and C-, at 3 months there were no differences, and between 1 and 3 months PR had greater increase growthing. Connective tissue at 1 month was higher for C-, at 3 months for PR, TG and C-, and between 1 and 3 months C- had sharp decline. Biomaterial at 1 month was higher for LC, in 3 months for SP and TG, and between 1 and 3 months, LC, GD and TG had more decreasing mean. Conclusion: SP had greater osteopromotive capacity and limitation of connective ingrowth, but did not exhibit degradation. PR and TG had favorable osteopromotion, LC less connective tissue and GD more accelerated biodegradation.

Biocompatibility in vivo of elastic cartilage treated in alkaline solutions / [Biocompatibilidade in vivo de cartilagem elástica tratada em soluções alcalinas]

This study verified the in vivo biocompatibility of bovine elastic cartilage decellularized with alkaline solution in relation to the non-decellularized cartilage implanted in rats. Fifty Wistar rats were divided into two groups, with the experimental group (EG) receiving subcutaneous implants of cartilage treated in alkaline solution and the control group (CG) receiving subcutaneous implants of untreated cartilage. In both groups, the implants were removed on days 3, 7, 14, 21 and 42 with the preparation of histological slides stained with Hematoxylin and Eosin for the quantification of inflammatory cells, fibroblasts, angiogenesis, and cartilage degradation. The results showed that EG presented a less intense inflammatory infiltrate and better organization of collagen fibers compared to CG. It was concluded that the alkaline treatment provided better biocompatibility for elastic cartilage when implanted subcutaneously in rats.

Este estudo verificou a biocompatibilidade in vivo de cartilagem elástica bovina descelularizada com solução alcalina em relação à cartilagem não descelularizada implantada em ratos. Cinquenta ratos Wistar foram divididos em dois grupos; o grupo experimental (GE) recebeu implantes subcutâneos de cartilagem tratada em solução alcalina, e o grupo controle (GC) recebeu implantes subcutâneos de cartilagem não tratada. Em ambos os grupos, os implantes foram retirados nos dias três, sete, 14, 21 e 42, com a preparação de lâminas histológicas coradas com hematoxilina e eosina para a quantificação de células inflamatórias, de fibroblastos, de angiogênese e para a degradação da cartilagem. Os resultados mostraram que o GE apresentou infiltrado inflamatório menos intenso e melhor organização das fibras de colágeno em relação ao GC. Concluiu-se que o tratamento alcalino proporcionou melhor biocompatibilidade para a cartilagem elástica quando implantado por via subcutânea em ratos.

Meat quality of the Berrichon du Cher lambs and its cross-breeds with a native breed / Qualidade da carne dos cordeiros Berrichon du Cher e seus cruzamentos com raça nativa

This study evaluated the meat of lambs from crossbreeding of Polish lowland sheep, heather and rams of the Berrichone du Cher breed (B). The lambs were kept in a medium-intensive feeding system. During fattening, they received haylage and grass hay with the addition of clover, and a mixture of cereal grains with the addition of minerals and vitamins. During the fattening period, all feeds were given at will. The slaughter and cutting of the carcasses were performed in accordance with the technology applicable in the meat industry. In the longissimus lumborum muscle, the content of dry matter, total protein, total fat and ash was determined. In addition, the pH value of 45 minutes and 24 hours after slaughter, as well as the parameters of colour and tenderness of the meat were measured. The content of collagen protein, cholesterol and selected fatty acids was also determined. As a result of the conducted analyzes, the influence of the Berrichone du Cher breed on the improvement of quantitative parameters related to the slaughter value and some parameters related to the physicochemical composition of the hybrid meat was reported.

O objetivo deste estudo foi avaliar como o cruzamento da raça Berrichon du Cher com raças nativas de ovelhas polonesas de baixa altitude e ovelhas de charneca polonesa afeta os parâmetros qualitativos da carne .O maior teor de proteína (19,86 ± 0,36%, P <0,05) em cordeiros foi encontrado no grupo Berrichon du Cher e no grupo de cordeiros ovinos (19,23 ± 0,67%, P <0,05). Por outro lado, o maior teor de colágeno total (1,10 ± 0,21%) e a maior sensibilidade do tecido muscular (10,69 ± 0,74 N cm-2), que também apresentaram o menor diâmetro das fibras musculares (24,01 ± 4,62 µm, P < 0,01) foi encontrado nos cordeiros mestiços Berrichon du Cher e Polish Heath Sheep. Tanto a raça quanto o gênero afetaram significativamente o teor de colesterol na carne de cordeiro e o maior teor de colesterol foi encontrado na carne dos cordeiros Berrichon du Cher. Seu menor teor foi demonstrado na carne de Ovinos da Baixada Polonesa com a diferença de 9,1 mg 100g-1 de tecido muscular. Um dos níveis mais baixos do isômero CLA (C 18: 2 cis-9 trans-11) também foi encontrado no grupo dos cordeiros Berrichon du Cher. Este isômero evita a formação de colesterol. Dependência semelhante em relação ao gênero também foi observada. Os resultados obtidos indicam que as raças nativas são utilizadas em cruzamentos com a raça Berrichon du Cher destinada à engorda, principalmente para melhorar parâmetros quantitativos relacionados ao valor de abate e parâmetros selecionados de propriedades físicas e químicas da carne ovina.

Gender, lineage, and age on muscle morphometry traits and meat tenderness of free-range chickens / Associação de fatores de produção e de morfometria muscular sobre a maciez da carne de frangos caipiras

This study assessed whether the meat tenderness of broilers raised in a free-range system varies by sex, lineage, and age at the time of slaughter. Physicochemical parameters were measured to adequately assess breast and thigh muscle morphometry, including shear force (SF), muscle fibre diameter (MD), histological connective tissue (HCT) content, and total and soluble collagen contents (TCC and SCC, respectively). The experiment was conducted with a completely randomized design using two lineages (Pescoço Pelado and Paraíso Pedrês), with specimens of both sexes raised in a free-range system. Randomly selected broilers were slaughtered at 65, 75, 85, and 95 days old. A total of 192 birds were analysed. SF values correlated positively with age. The highest SF values were measured in thighs of the Pescoço Pelado lineage. Age also showed a positive correlation with MD and HCT content of the breast regardless of lineage. Gender did not have any significant correlation with physical parameters; although, higher values were measured in thighs of the Paraíso Pedrês than in those of the Pescoço Pelado lineage. There were no significant differences among treatments regarding the SCC and TCC of thighs and breasts. Principal component analysis (PCA) revealed relationships between SF and the rest of the measured attributes. PCA showed that age was positively correlated with the SF, MD, and HCT content of thighs and breasts. In contrast, SCC and TCC had negative correlations. The greatest breast and thigh MD values were associated with the least tender meat. Thus, age at the time of slaughter proved to be the most significant parameter impacting the physical characteristics of muscle morphometry and meat tenderness of breasts and thighs of broilers raised in a free-range system.

Objetivou-se com este estudo avaliar os fatores relacionados a maciez da carne de frangos criados em sistema alternativo. Para o experimento foi avaliado a força de cisalhamento, diâmetro das fibras musculares do peito e da coxa, conteúdo de tecido conjuntivo através de histologia e teor de colágeno solúvel e total. O experimento foi executado em delineamento inteiramente casualizado (DIC) com uso de duas linhagens (Pescoço Pelado e Paraíso Pedrês) de ambos os sexos (macho e fêmea) e abatidos em quatro idades (65, 75, 85 e 95 dias), criados em sistema alternativo, sendo utilizado um total de 192 aves. Para força de cisalhamento (FC), ocorreu aumento nos valores em ambos os cortes em função da idade de abate e houve interação entre linhagem e sexo, com as maiores médias para os machos da linhagem Pescoço Pelado e diferença entre sexo para Paraíso Pedrês. A idade de abate influenciou o diâmetro das fibras musculares e o conteúdo de tecido conjuntivo do peito e da coxa, havendo aumento linear destes parâmetros em função da idade ao abate. O sexo não afetou o diâmetro das fibras musculares da coxa, enquanto na linhagem Paraíso Pedrês foram verificadas maiores médias em relação à Pescoço Pelado. A análise de componentes principais demonstrou a relação entre a força de cisalhamento e as demais variáveis analisadas. Assim, o aumento do diâmetro das fibras musculares do peito e da coxa também está relacionado à redução da maciez da carne de frangos caipiras, conjuntamente com o aumento da quantidade de tecido conjuntivo, teor de colágeno total e redução de sua solubilidade.

Ehlers-Danlos syndrome in a crossbreed cat / Síndrome de Ehlers-Danlos em um gato mestiço

The Ehlers-Danlos syndrome (EDS) consists of a group of diseases characterized by defective collagen production or failure in its organization, resulting in changes in the strength and extensibility of connective tissue. This report describes the dermatological and histological findings observed in a 3-month-old crossbreed cat with rupture and detachment of skin in the thoracic limb and rupture of the skin in the cervical region. Upon dermatological examination, the cat presented fragile and hyperextensible skin in the cervical region and a skin extensibility index of 21%. Histopathological evaluation of the skin specimens revealed evident disorganization of collagen bundles in dermis and in the Masson's trichrome staining, follicular dysplasia was found. The presumptive diagnosis of EDS was made based on the clinical and histopathological findings. Sanger sequencing did not detect any mutated alleles for the c.3420delG mutation in COL5A1 gene, which was an autosomal dominant mutation previously been associated with Ehlers-Danlos syndrome in cats. The absence of this mutation in the reported cat suggests that other mutation may also be responsible for the development of cutaneous asthenia in this or maybe other genes related to collagen metabolism.

A síndrome de Ehlers-Danlos (EDS) consiste em um conjunto de doenças caracterizadas pela produção deficiente de colágeno ou falha em sua organização, resultando em alterações na resistência e extensibilidade do tecido conjuntivo. Este relato descreve os achados dermatológicos e histológicos observados em um gato mestiço de três meses de idade com ruptura e descolamento de pele do membro torácico e ruptura da pele na região cervical. Ao exame dermatológico, o gato apresentava pele hiper-extensível, fragilizada na região cervical e índice de extensibilidade cutânea de 21%. A avaliação histopatológica das amostras de pele revelou desorganização evidente dos feixes de colágeno na derme e pela coloração com tricrômico de Masson foi encontrada displasia folicular. O diagnóstico presuntivo de EDS foi realizado com base nos achados clínicos e histopatológicos. O sequenciamento de Sanger não detectou nenhum alelo mutado para a mutação c.3420delG no gene COL5A1, que é uma mutação autossômica dominante previamente associada à síndrome de Ehlers-Danlos em gatos. A ausência dessa mutação no gato relatado sugere que outra mutação também pode ser responsável pelo desenvolvimento de astenia cutânea neste gene ou em outro associado ao metabolismo de colágeno.

A biocomplex to repair experimental critical size defects associated with photobiomodulation therapy

The association of scaffolds to repair extensive bone defects can contribute to their evolution and morphophysiological recomposition. The incorporation of particulate biomaterials into three-dimensional fibrin bioproducts together with photobiomodulation therapy (PBM) has potential and can improve regenerative medicine procedures. The objective of this experiment was to evaluate the effects of PBM therapy on critical size defects filled with xenogenic bone substitute associated with fibrin biopolymer. Methods: A critical defect of 8 mm was performed in 36 Wistar male adult rats that were divided into four groups. Groups BC and BC-PBM were defined as controls with defects filled by a clot (without or with PBM, respectively) and groups XS and XS-PBM that comprised those filled with biocomplex Bio-OssTM in association with fibrin biopolymer. PBM was applied immediately after the surgery and three times a week every other day, with the parameters: wavelength of 830 nm, energy density 6.2 J/cm2, output power 30 mW, beam area of 0.116 cm2, irradiance 0.258,62 W/cm2, energy/point 0.72 J, total energy 2.88 J. Fourteen and 42 days after the surgery, animals were euthanatized and subjected to microtomography, qualitative and quantitative histological analysis. Results: The BC-PBM and XS-PBM groups had a similar evolution in the tissue repair process, with a higher density of the volume of new formed bone in relation to the groups without PBM (p = 0.04086; p = 0.07093, respectively). Intense vascular proliferation and bone deposition around the biomaterial particles were observed in the animals of the groups in which biocomplex was applied (XS and XS-PBM). Conclusion: PBM therapy allowed an improvement in the formation of new bone, with a more organized deposition of collagen fibers in the defect area. Biocomplex favored the insertion and permanence of the particulate material in bone defects, creating a favorable microenvironment for accelerate repair process.(AU)

Development and characterization of poultry collagen-based hybrid hydrogels for bone regeneration

Purpose: Poultry by-products can contribute as an innovative natural source for the development of composites based on polymers and minerals aiming at bone regeneration. The objective of this study was the physicochemical and biological characterization of collagen-based hydrogels crosslinked with ultraviolet (UV)-riboflavin. Methods: Pure hydrogels of 100% collagen (G1) or hybrid hydrogels, 90% collagen:10% apatite (G2), 90% collagen:10% nanokeratin (G3), and 90% collagen:5% apatite:5% nanokeratin (G4) were characterized by scanning electron microscope, Fourier-transform infrared spectroscopy, differential scanning calorimetry, swelling degree and quali-quantitative histological analysis. Ectopic implantation in subcutaneous tissue in mice at one, three and nine weeks allowed to assess the inflammation (neutrophils, lymphocytes, macrophages, and giant cells) and repair (neovascularization, and connective tissue) to determine biocompatibility and the integrity of biomaterials to score their biodegradability. Histomorphometry on critical size defects in rat calvaria at one and three months evaluated the percentage of bone, connective tissue, and biomaterials in all groups. Results: The hydrogels presented porous microstructure, water absorption and physicochemical characteristics compatible with their polymeric and/or mineral composition. All materials exhibited biocompatibility, biodegradability, and low osteoconductivity. G2 showed greater density of new bone and biomaterial than the G1, G3 and G4. Conclusions: The collagen-apatite group formulation suggests potential for development as osteopromoting membrane.

Free omental graft without vascular microanastomosis in the cutaneous wound healing of rabbits / [Enxerto omental livre sem microanastomose vascular na cicatrização de feridas cutâneas em coelhos]

This study aims to evaluate the influence of free omental graft without vascular microanastomosis (FOGWVA) on experimental skin healing in rabbits. Through celiotomy, a 9cm2 free omental fragment was collected in 36 rabbits, with subsequent production of a deep linear cutaneous wound in the dorsal midline measuring 3cm. In 18 animals from the omental group (OG), the omental fragment collected was fixed subcutaneously with six simple interrupted stitches using a 4-0 polyamide thread. In both treated and control (CG) groups, intradermal dermorrhaphy was performed with 4-0 polyamide thread. Experimental wounds were clinically evaluated every day. Each of the groups was divided into three subgroups of 6 animals each for histopathological evaluation on the 7th, 14th, and 28th days of postoperative. In the OG wounds, the increase in volume (omentum activation) stood out after the second postoperative day. Macroscopy showed an organic reaction to the graft on day 7, with a progressive reduction in addition to neovascularization towards the omental graft. The intense presence of mononuclear cells and collagen deposition on day 7 demonstrated an accelerated process of tissue remodeling and repair. The FOGWVA omental graft remained viable and positively influenced the cutaneous healing of the experimental wounds in rabbits.

Neste estudo, objetiva-se avaliar a influência do enxerto omental livre sem microanastomose vascular (FOGWVA) na cicatrização cutânea experimental em coelhos. Por meio de celiotomia, foi coletado fragmento omental livre de 9cm2 em 36 coelhos, com posterior produção de ferida cutânea profunda linear na linha média dorsal medindo 3cm. Apenas em 18 animais, do grupo omento (GO), o fragmento omental coletado foi fixado no subcutâneo com seis pontos simples interrompidos utilizando fio poliamida 4-0. Em ambos os grupos, tratado e controle (GC), efetuou-se dermorrafia intradérmica com fio poliamida 4-0. As feridas experimentais foram avaliadas clinicamente todos os dias. Cada um dos grupos foi dividido em três subgrupos, com seis animais cada, para avaliação anatomopatológica no sétimo, 14º e 28o dias de pós-operatório. Nas feridas do GO, destacou-se aumento de volume (ativação do omento) a partir do segundo dia pós-operatório. A macroscopia evidenciou reação orgânica ao enxerto no dia sete, com redução progressiva, além de neovascularização em direção ao enxerto omental. Intensa presença de células mononucleares e deposição de colágeno no dia sete demonstraram acelerado processo de remodelamento e reparo tecidual. O FOGWVA manteve-se viável e influenciou positivamente na cicatrização cutânea de feridas experimentais em coelhos.

Carangoides bartholomaei (Cuvier, 1833) stomach: a source of aspartic proteases for industrial and biotechnological applications / Estômago de Carangoides bartholomaei (Cuvier, 1833): uma fonte de proteases aspárticas para aplicações industriais e biotecnológicas

The viscera and other residues from fish processing are commonly discarded by the fishing industry. These by products can be a source of digestive enzymes with industrial and biotechnological potential. In this study, we aimed at the extraction, characterization, and application of acidic proteases from the stomach of Carangoides bartholomaei (Cuvier, 1833). A crude extract from the stomachs was obtained and submitted to a partial purification process by salting-out, which obtained a Purified Extract (PE) with a specific proteolytic activity of 54.0 U·mg-¹. A purification of 1.9 fold and a yield of 41% were obtained. The PE presents two isoforms of acidic proteases and a maximum proteolytic activity at 45 °C and pH 2.0. The PE acidic proteolytic activity was stable in the pH range of 1.5 to 7.0 and temperature from 25 °C to 50 °C. Purified Extract kept 35% of its proteolytic activity at the presence of NaCl 15% (m/v) but was totally inhibited by pepstatin A. Purified Extract aspartic proteases presented high activity in the presence of heavy metals such as Cd2+, Hg2+, Pb2+, Al3+, and Cu2+. The utilization of PE as an enzymatic addictive in the collagen extraction from Nile tilapia scales has doubled the process yield. The results indicate the potential of these aspartic proteases for industrial and biotechnological applications.

As vísceras e outros resíduos do processamento de peixes são geralmente descartados pela indústria pesqueira. Esses resíduos podem ser uma fonte de enzimas digestivas com potencial industrial e biotecnológico. Neste estudo, objetivamos a extração, caracterização e aplicação de proteases aspárticas do estômago de Carangoides bartholomaei (Cuvier, 1833). Um extrato bruto do estômago foi obtido e submetido a um processo de purificação parcial, que obteve um Extrato Purificado (EP) com uma atividade proteolítica específica de 54,0 U·mg-¹. Foi obtida uma purificação de 1,9 vezes e um rendimento de 41%. O EP apresenta duas isoformas de proteases ácidas e atividade proteolítica máxima a 45 °C e pH 2,0. A atividade proteolítica do EP foi estável na faixa de pH de 1,5 a 7,0 e temperatura de 25 °C a 50 °C. O EP manteve 35% de sua atividade proteolítica na presença de NaCl a 15% (m/v), mas foi totalmente inibida pela pepstatina A. As proteases ácidas do EP apresentaram alta atividade na presença de metais pesados como o Cd2+, Hg2+, Pb2+, Al3+ e Cu2+. A utilização de EP como aditivo enzimático na extração de colágeno a partir de escamas de tilápia do Nilo dobrou o rendimento do processo. Os resultados indicam um potencial dessas proteases para aplicações industriais e biotecnológicas.

Carangoides bartholomaei (Cuvier, 1833) stomach: a source of aspartic proteases for industrial and biotechnological applications / Estômago de Carangoides bartholomaei (Cuvier, 1833): uma fonte de proteases aspárticas para aplicações industriais e biotecnológicas

The viscera and other residues from fish processing are commonly discarded by the fishing industry. These by products can be a source of digestive enzymes with industrial and biotechnological potential. In this study, we aimed at the extraction, characterization, and application of acidic proteases from the stomach of Carangoides bartholomaei (Cuvier, 1833). A crude extract from the stomachs was obtained and submitted to a partial purification process by salting-out, which obtained a Purified Extract (PE) with a specific proteolytic activity of 54.0 U·mg-¹. A purification of 1.9 fold and a yield of 41% were obtained. The PE presents two isoforms of acidic proteases and a maximum proteolytic activity at 45 °C and pH 2.0. The PE acidic proteolytic activity was stable in the pH range of 1.5 to 7.0 and temperature from 25 °C to 50 °C. Purified Extract kept 35% of its proteolytic activity at the presence of NaCl 15% (m/v) but was totally inhibited by pepstatin A. Purified Extract aspartic proteases presented high activity in the presence of heavy metals such as Cd2+, Hg2+, Pb2+, Al3+, and Cu2+. The utilization of PE as an enzymatic addictive in the collagen extraction from Nile tilapia scales has doubled the process yield. The results indicate the potential of these aspartic proteases for industrial and biotechnological applications.(AU)

As vísceras e outros resíduos do processamento de peixes são geralmente descartados pela indústria pesqueira. Esses resíduos podem ser uma fonte de enzimas digestivas com potencial industrial e biotecnológico. Neste estudo, objetivamos a extração, caracterização e aplicação de proteases aspárticas do estômago de Carangoides bartholomaei (Cuvier, 1833). Um extrato bruto do estômago foi obtido e submetido a um processo de purificação parcial, que obteve um Extrato Purificado (EP) com uma atividade proteolítica específica de 54,0 U·mg-¹. Foi obtida uma purificação de 1,9 vezes e um rendimento de 41%. O EP apresenta duas isoformas de proteases ácidas e atividade proteolítica máxima a 45 °C e pH 2,0. A atividade proteolítica do EP foi estável na faixa de pH de 1,5 a 7,0 e temperatura de 25 °C a 50 °C. O EP manteve 35% de sua atividade proteolítica na presença de NaCl a 15% (m/v), mas foi totalmente inibida pela pepstatina A. As proteases ácidas do EP apresentaram alta atividade na presença de metais pesados como o Cd2+, Hg2+, Pb2+, Al3+ e Cu2+. A utilização de EP como aditivo enzimático na extração de colágeno a partir de escamas de tilápia do Nilo dobrou o rendimento do processo. Os resultados indicam um potencial dessas proteases para aplicações industriais e biotecnológicas.(AU)

Carboxymethyl chitosan hydrogel formulations enhance the healing process in experimental partial-thickness (second-degree) burn wound healing

ABSTRACT Purpose This study aimed to elaborate a hydrogel constituted by carboxymethyl chitosan (CMC), hyaluronic acid (HA) and silver (Ag) and to evaluate its healing effect on partial-thickness burn wounds experimentally induced in rats. Methods CMC was obtained by chitosan reacting with monochloroacetic acid. The carboxymethylation was confirmed by Fourier-transform infrared spectroscopy and hydrogen nuclear magnetic resonance (NMR). Scanning electron microscopy was used to determine the morphologicalcharacteristics of chitosan and CMC. After the experimental burn wound induction, the animals (n = 126) were treated with different CMC formulations, had their occlusive dressings changed daily and were followed through 7, 14 and 30 days. Morphometric, macroscopic and microscopic aspects and collagen quantification were evaluated. Results Significative wound contraction, granulation tissue formation, inflammatory infiltration and collagen fibers deposit throughout different phases of the healing process were observed in the CMC hydrogels treated groups. Conclusions The results showed that, in the initial phase of the healing process, the most adequate product was the CMC/HA/Ag association, while in the other phases the CMC/HA association was the best one to promote the healing of burn wounds.

Histological evaluation of capsules formed by texturized silicone implants with and without polyester mesh coverage (Parietex®). A study on female rats

ABSTRACT Purpose To evaluate capsules formed by microtextured silicone implants with and without Parietex® mesh coverage histologically. Methods Sixty Wistar rats were divided in two groups (meshed and unmeshed). Each group was, then, divided into two subgroups for evaluation at 30 and 90 days. Capsules were analyzed based on hematoxylin and eosin (HE) and picrosirius staining. Results The number of fibroblasts, neutrophils and macrophages was similar among all subgroups. There was a higher lymphocyte reaction in the 30-day meshed group (p = 0.003). Giant cell reaction, granulation tissue and neoangiogenesis were similar among the subgroups. Synovial metaplasia was milder at 90-day in the unmeshed (p = 0.002) and meshed group (p < 0.001). Capsular thickness was significantly greater in the meshed samples (30-day p < 0.001 and 90-day p < 0.001). There was a similar amount of collagen types I and III in both groups. Conclusions The mesh-covered implants produced capsules similar to the microtextured ones when analyzing inflammatory variables. Synovial metaplasia was milder at 90 than at 30 days, and the capsular thickness was significantly greater in the meshed group. A similar amount of collagen types I and III was observed. Due to these characteristics, the mesh coverage did not seem to significantly affect the local inflammatory activity.

Effect of low-level laser therapy on the membrane induced by the Masquelet technique at an orthotopic site in rabbits

ABSTRACT Purpose: To evaluate the low-level laser therapy (LLLT) on the membrane induced by the Masquelet technique in rabbits. Methods: Twelve Norfolk rabbits at approximately 3 months of age were used. A 1-cm segmental defect was induced in both radii, which were filled with polymethylmethacrylate cylinder. LLLT was used postoperatively in the bone defect of one of the forelimbs every 48 hours for 15 days. Six rabbits were euthanatized on third and sixth postoperative weeks. Results: In both forelimbs, radiographs showed new bone growth from radius cut ends on the third postoperative week and more advanced stage on the sixth postoperative week. Ultrasound showed induced membrane one week after the surgery. Histologically, there were no significant differences in the semi-quantitative score of inflammation intensity, total number of blood vessels, bone metaplasia, and collagen. The average thicknesses were 2,050.17 and 1,451.96 μm for control membranes and 2,724.26 and 2,081.03 μm for irradiated membranes, respectively, on third and sixth postoperative weeks. Vascular endothelial growth factor A (VEGF-A) and platelet derived growth factor (PDGF) expression were present in the induced membranes of control and irradiated forelimbs, but there was no significant difference. Conclusions: Based on assessment methods, it was not possible to demonstrate the effect of LLLT on the induced membrane.

Analysis of tissue inflammatory response, fibroplasia, and foreign body reaction between the polyglactin suture of abdominal aponeurosis in rats and the intraperitoneal implant of polypropylene, polypropylene/polyglecaprone and polyester/porcine collagen meshes

ABSTRACT 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.

Formulation of fishburgers with the addition of different protein sources and taro flour / Formulação de fishburgers com adição de diferentes fontes proteicas e farinha de taro

The present study aims to develop Nile tilapia hamburger with incorporation of whey, collagen from chicken feet and taro flour. A complete factorial design 2³ was performed to investigate the influence of the variables on weight loss, shrinkage, color and shear force, that were used to propose mathematical models. Proximate composition, microbiological characteristics and sensory properties were also evaluated. Factors such as taro flour and whey were significant and contributed to a higher yield for fish burgers, with negative effects on shrinkage and weight loss. The fishburgers had a soft texture, although collagen and its interaction with taro flour contributed to the increase in shear force. The factors had influence only on the b* value with yellowish hue. The protein and ash values obtained were higher than those of the control formulation. The sensory characteristics of the hamburgers were not affected by the factors, being all classified with high acceptability. The formulation represented by the central point (F9) containing 3.0% of taro flour, 0.5% chicken feet collagen and 3.0% powdered whey, obtained greater purchase intention. Therefore, the addition of taro flour, collagen from chicken feet and whey is an alternative in the use of industrial by-products to add value to fish burgers with market potential.(AU)

O objetivo do presente estudo foi desenvolver hambúrguer de tilapia do Nilo com a incorporação de soro de leite, colágeno de pés de frango e farinha de taro. Para tanto, um planejamento fatorial 2³ completo foi realizado para investigar a influência das variáveis sobre a perda de peso, encolhimento, cor e força de cisalhamento e propor modelos matemáticos. Avaliaram-se também a composição centesimal, características microbiológicas e propriedades sensoriais. Os fatores como farinha de taro e whey foram significativos e contribuíram com o maior rendimento dos hambúrgueres com efeitos negativos sobre a perda de peso e encolhimento. Os hambúrgueres apresentaram uma textura macia, embora o colágeno e sua interação com a farinha de taro tenham colaborado com o aumento da força de cisalhamento. Os fatores influenciaram somente o valor de b* com tonalidade amarelada. Os valores de proteína obtidos foram maiores que da formulação controle. As características sensoriais dos hambúrgueres não foram afetadas pelos fatores, sendo todos classificados com alta aceitabilidade. A formulação representada pelo ponto central (F9) contendo 3,0% de farinha de taro, 0,5% de colágeno de pés de frango e 3,0% de soro de leite em pó, obteve maior intenção de compra. Portanto, a adição de farinha de taro, colágeno de pés de frango e soro de leite é uma alternativa no uso de subprodutos industriais para agregar valor aos hambúrgueres de peixe com potencial mercadológico.(AU)

Histological evaluation of the effect of low-frequency electric stimulation on healing Achilles tendons in rats

Purpose: Histologically evaluate the effects of low frequency electrical stimulation in the treatment of Achilles tendon injuries in rats. Methods: Thirty-four rats underwent Achilles tendon tenotomy and tenorrhaphy. They were randomly allocated in two groups. Half of the sample constituted the experiment group, whose lesions were stimulated with 2 Hz, nonpolarized current and 1 mA, for 14 days. The other animals formed the control group. They were evaluated at 2, 4 and 6 weeks. The histological study was carried out, the collagen density and the wound maturity index were measured. Results: The healing score was higher in the group stimulated at the 6th week (p = 0.018). The density collagen 1 was higher in the group treated at the three times (p = 0.004) and that collagen 3 was higher in the group treated at 6 weeks (p = 0.004). Together, collagen 1 and 3 were higher in the group stimulated at 4 and 6 weeks (p = 0.009, p = 0.004). The maturity index was higher in this group at the three moments (p = 0.017 p = 0.004 and p = 0.009). Conclusion: Low frequency electric stimulation improved healing and increased the quantity of collagen.(AU)

Quantification of the collagen fibers of healthy and neoplastic mammary tissue in cats by the Picrossirius Red histochemical method

Although feline mammary carcinoma is not the most prevalent among the species, its aggressive behavior represents a low life expectancy, compared with most undifferentiated types of breast cancer. Tissue stiffness induced by the accumulation of collagen fibers is related to a risk factor for carcinogenesis in healthy women and aggressiveness in those with breast cancer, which can also occur in cats. The objective of this work is to identify the relationship between stromal collagen density and aggressiveness of mammary carcinoma in cats, according to the peripheral and central tissue distribution by the Picrossirius Red histochemical method. Image.J® and MatLab® software were used for digital image processing. The mean values of kurtosis and entropy attributes were ​​grouped into a control group, and low and high-grade carcinoma groups, analyzed with one-way ANOVA and Bonferroni’s multiple comparison test (p <0.01). Interpretation of stromal dynamics is important to evaluate both central and peripheral locations. According to entropy, there was a significant increase in the peripheral density in the carcinoma groups in relation to the control group, which can be justified by blood support. The same can be said of the central region, with a significant gain in collagen fibers from the tumors, indicated by kurtosis. The results suggest the presence of increases in stromal density in mammary carcinomas of cats, regardless of their graduation, and occurring in both regions.

Quantification of the collagen fibers of healthy and neoplastic mammary tissue in cats by the Picrossirius Red histochemical method

Although feline mammary carcinoma is not the most prevalent among the species, its aggressive behavior represents a low life expectancy, compared with most undifferentiated types of breast cancer. Tissue stiffness induced by the accumulation of collagen fibers is related to a risk factor for carcinogenesis in healthy women and aggressiveness in those with breast cancer, which can also occur in cats. The objective of this work is to identify the relationship between stromal collagen density and aggressiveness of mammary carcinoma in cats, according to the peripheral and central tissue distribution by the Picrossirius Red histochemical method. Image.J® and MatLab® software were used for digital image processing. The mean values of kurtosis and entropy attributes were ​​grouped into a control group, and low and high-grade carcinoma groups, analyzed with one-way ANOVA and Bonferronis multiple comparison test (p <0.01). Interpretation of stromal dynamics is important to evaluate both central and peripheral locations. According to entropy, there was a significant increase in the peripheral density in the carcinoma groups in relation to the control group, which can be justified by blood support. The same can be said of the central region, with a significant gain in collagen fibers from the tumors, indicated by kurtosis. The results suggest the presence of increases in stromal density in mammary carcinomas of cats, regardless of their graduation, and occurring in both regions.(AU)

Effects of the lower energy and pulse stacking in carbon dioxide laser skin treatment: an objective analysis using second harmonic generation

Purpose: To evaluate the effect of fractional carbon dioxide (CO2 ) laser treatment using lower power associated with pulse stacking within collagen fibers, using second harmonic generation microscopy and computerized image analysis. Methods: Twenty male Wistar rats aging eight weeks were used. Each treatment area received a single-pass CO2 fractional laser with different parameters. The 20 animals were divided into two groups and euthanized after 30 and 60 days. Second harmonic generation images were obtained and program ImageJ was utilized to evaluate the collagen organization within all areas. Collagen anisotropy, entropy and optical density were quantified. Results: Increased anisotropy over time was observed in all four areas, but only reached statistical significance (p = 0.0305) when the mildest parameters were used (area four). Entropy decreased over time in all areas, but without significance (p = 0.1779) in area four. Density showed an overtime increase only in area four, but no statistical significance was reached (p = 0.6534). Conclusion: When combined, the results obtained in this study regarding anisotropy, entropy and density tend to demonstrate that it is possible to achieve collagen remodeling with the use of lower power levels associated with stacked pulses.(AU)

Análise ultraestrutural do colágeno de feridas cutâneas de coelhos tratadas com plasma rico em plaquetas de equino / Ultrastructural analysis of the collagen of rabbit skin wounds treated with platelet-rich equine plasma

O colágeno é sintetizado e segregado no espaço extracelular e organizados em fibrilas estriadas de acordo com o tipo de tecido. Utilizaram-se 24 coelhos brancos da raça Nova Zelândia, com idade de 12 meses e com 3,0kg de peso corporal, para avaliar a porcentagem de colágeno das feridas cutâneas tratadas com plasma rico em plaquetas de equino e pomada contendo gentamicina, sulfanilamida, sulfadiazina, ureia e vitamina A. Os animais foram separados em quatro grupos de igual número e submetidos à remoção de pele na região das linhas médias dorsal torácica (feridas tratadas) e lombar (feridas controle). As feridas torácicas foram tratadas com plasma rico em plaqueta de equino e pomada contendo gentamicina, sulfanilamida, sulfadiazina, ureia e vitamina A, e as do grupo controle somente com a pomada. Dos animais do grupo I, foi coletado tecido cutâneo, para a avaliação histológica e a ultraestrutural, com três dias de pós-operatório; dos animais do grupo II, com sete dias; do grupo III, com 14 dias; e do grupo IV, com 21 dias. Decorrido o período de avaliação de cada grupo, foi coletado fragmento de pele para avaliação da porcentagem de colágeno, bem como do diâmetro e da densidade da fibrila de colágeno por microscopia eletrônica de transmissão. O tratamento com PRP de equino associado à aplicação tópica da pomada mostrou-se eficaz na maturação das fibrilas colágenas e na antecipação do processo cicatricial.(AU)

Collagen is synthesized and secreted into the extracellular space and organized into striated fibrils according to the tissue type. This study evaluated the concentration of collagen in rabbit skin wounds treated with equine platelet-rich plasma (PRP) and ointment containing gentamicin, sulfanilamide, sulfadiazine, urea, and vitamin A. Twenty-four New Zealand white rabbits aged 2 to 12 months and weighing 3.0kg were included. The animals were allocated equally into four groups and the skin was removed from the thoracic dorsal midline (treated wound) and lumbar (control wound) regions. The thoracic wounds were treated with equine PRP and ointment containing gentamicin, sulfanilamide, sulfadiazine, urea, and vitamin A, and the control group was treated with the ointment alone. For histological and ultrastructural assessment, cutaneous tissue was collected on postoperative days 3 (group I), 7 (group II), 14 (group III), and 21 (group IV). After the evaluation period, in each group, a skin fragment was collected for analysis of the collagen concentration, as well as the collagen fibril diameter and density by transmission electron microscopy. The results indicated that treatment with equine PRP combined with topical application of the ointment was effective in facilitating the maturation of collagen fibrils and the wound healing process.(AU)