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Due to bioactive properties, introducing spongin-like collagen (SPG) into the biosilica (BS) extracted from marine sponges would present an enhanced biological material for improving osteoporotic fracture healing by increasing bone formation rate. Our aim was to characterize the morphology of the BS/SPG scaffolds by scanning electron microscopy (SEM), the chemical bonds of the material by Fourier transform infrared spectroscopy (FTIR), and evaluating the orthotopic in vivo response of BS/SPG scaffolds in tibial defects of osteoporotic fractures in rats (histology, histomorphometry, and immunohistochemistry) in two experimental periods (15 and 30 days). SEM showed that scaffolds were porous, showing the spicules of BS and fibrous aspect of SPG. FTIR showed characteristic peaks of BS and SPG. For the in vivo studies, after 30 days, BS and BS/SPG showed a higher amount of newly formed bone compared to the first experimental period, observed both in the periphery and in the central region of the bone defect. For histomorphometry, BS/SPG presented higher %BV/TV compared to the other experimental groups. After 15 days, BS presented higher volumes of collagen type I. After 30 days, all groups demonstrated higher volumes of collagen type III compared to volumes at 15 days. After 30 days, BS/SPG presented higher immunostaining of osteoprotegerin compared to the other experimental groups at the same experimental period. The results showed that BS and BS/SPG scaffolds were able to improve bone healing. Future research should focus on the effects of BS/SPG on longer periods in vivo studies.

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BACKGROUND: Previous studies have experimentally validated and reported that chemical constituents of marine sponges are a source of natural anti-inflammatory substances with the biotechnological potential to develop novel drugs. AIMS: Therefore, the aim of this study was to perform a systematic review to provide an overview of the anti-inflammatory substances isolated from marine sponges with therapeutic potential. METHODS: This systematic review was performed on the Embase, PubMed, Scopus and Web of Science electronic databases. In total, 613 were found, but 340 duplicate studies were excluded, only 100 manuscripts were eligible, and 83 were included. RESULTS: The results were based on in vivo and in vitro assays, and the anti-inflammatory effects of 251 bioactive compounds extracted from marine sponges were investigated. Their anti-inflammatory activities include inhibition of pro-inflammatory mediators, such as tumor necrosis factor- α (TNF-α), interleukin-6 (IL-6), nitrite or nitric oxide (NO), inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), interleukin 1ß (IL-1ß), prostaglandin E2 (PGE2), phospholipase A2 (PLA2), nuclear transcription factor-kappa B (NF-κB), leukotriene B4 (LTB4), cyclooxygenase- 1 (COX-1), and superoxide radicals. CONCLUSION: In conclusion, data suggest (approximately 98% of articles) that substances obtained from marine sponges may be promising for the development of novel anti-inflammatory drugs for the treatment of different pathological conditions.

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INTRODUCTION: Chitosan (CS) is a polycationic polysaccharide comprising glucosamine and N-acetylglucosamine and constitutes a potential material for use in cartilage tissue engineering. Moreover, CS hydrogels are able to promote the expression of cartilage matrix components and reduce inflammatory and catabolic mediator production by chondrocytes. Although all the positive outcomes, no review has analyzed the effects of CS hydrogels on cartilage repair in animal models. METHODS: This study aimed to review the literature to examine the effects of CS hydrogels on cartilage repair in experimental animal models. The search was done by the descriptors of the Medical Subject Headings (MeSH) defined below: "Chitosan," "hydrogel," "cartilage repair," and "in vivo." A total of 420 articles were retrieved from the databases Pubmed, Scopus, Embase, Lilacs, and Web of Science. After the eligibility analyses, this review reported 9 different papers from the beginning of 2002 through the middle of 2022. RESULTS: It was found that cartilage repair was improved with the treatment of CS hydrogel, especially the one enriched with cells. In addition, CS hydrogel produced an upregulation of genes and proteins that act in the cartilage repair process, improving the biomechanical properties of gait. CONCLUSION: In conclusion, CS hydrogels were able to stimulate tissue ingrowth and accelerate the process of cartilage repair in animal studies.

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The use of 3D-printed hydroxyapatite (HA) scaffolds for stimulating bone healing has been increasing over the years. Although all the promising effects of these scaffolds, there are still few studies and limited understanding of their interaction with bone tissue and their effects on the process of fracture healing. In this context, this study aimed to perform a systematic literature review examining the effects of different 3D-printed HA scaffolds in bone healing. The search was made according to the preferred reporting items for systematic reviews and meta-analysis (PRISMA) orientations and Medical Subject Headings (MeSH) descriptors "3D printing," "bone," "HA," "repair," and "in vivo." Thirty-six articles were retrieved from PubMed and Scopus databases. After eligibility analyses, 20 papers were included (covering the period of 2016 and 2021). Results demonstrated that all the studies included in this review showed positive outcomes, indicating the efficacy of scaffolds treated groups in the in vivo experiments for promoting bone healing in different animal models. In conclusion, 3D-printed HA scaffolds are excellent candidates as bone grafts due to their bioactivity and good bone interaction.

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Collagen (Col) from marine organisms has been emerging as an important alternative for commercial Col and it has been considered highly attractive by the industry. Despite the positive effects of Col from marine origin, there is still limited understanding of the effects of this natural biomaterial in the process of wound healing in animal studies. In this context, the purpose of this study was to perform a systematic review of the literature to examine the effects of Col from different marine species in the process of skin tissue healing using experimental models of skin wound. The search was carried out according to the orientations of Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA), and the descriptors of the Medical Subject Headings (MeSH) were defined: "marine collagen," "spongin," "spongin," "skin," and "wound." A total of 42 articles were retrieved from the databases PubMed and Scopus. After the eligibility analyses, this review covers the different marine sources of Col reported in 10 different papers from the beginning of 2011 through the middle of 2019. The results were based mainly on histological analysis and it demonstrated that Col-based treatment resulted in a higher deposition of granulation tissue, stimulation of re-epitalization and neoangiogenesis and increased amount of Col of the wound, culminating in a more mature morphological aspect. In conclusion, this review demonstrates that marine Col from different species presented positive effects on the process of wound skin healing in experimental models used, demonstrating the huge potential of this biomaterial for tissue engineering proposals.

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Membranes or skin dressing are common treatments for skin wound injuries, collagen being one the most effective materials for their manufacturing. Many different sources of collagen with diverse methods of extraction and processing have been used, with evidence of positive effects on the stimulation of skin wound healing. In spite of these factors, there is still limited understanding of the interaction between collagen membranes and biological tissues, especially due to the series of different types of collagen origin. In this context, this study aimed to conduct a systematic review of the available literature examining the effect of various collagen membranes for accelerating skin wound healing in experimental animal models and clinical trials. The present review was performed from March to May of 2020 searching in two databases (PubMed and Scopus). The following Medical Subject Headings (MeSH) descriptors were used: "collagen", "dressing", "membranes", "skin" and "wound". After the eligibility assessment, 16 studies were included and analyzed. The studies demonstrated that collagen was obtained predominantly from bovine and porcine sources, by acetic acid and/or enzyme dissolution. Additionally, most of the studies demonstrated that the membranes were processed mainly by freeze-drying or lyophilization methods. All the in vivo and clinical trial studies evidenced positive outcomes in the wound healing process, thus confirming that collagen membranes are one of the most efficient treatment for skin wounds, highlighting the enormous potential of this biomaterial to be used for skin tissue engineering purposes.

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This study evaluated the physicochemical and morphological properties of a marine sponge protein extract (PE) using scanning electron microscopy (SEM), Energy dispersive X-ray spectroscopy (EDS), analysis of mass loss and pH and in vitro and in vivo. Scanning electron microscopy showed that PE fibers present a granular aspect and irregular structure and the element carbon followed by oxygen was detected in the EDS analysis. Moreover, a 29% of mass loss was observed after 14 days and the pH slightly modified after 14 days. Cell viability of fibroblast cells (L929) of control and PE at a concentration of 25% demonstrated higher values compared to the groups. Osteoblast cell viability of PE at 25 and 50% was significantly higher. Comet assay on day 1 showed higher values for PE at 25%. In addition, in vivo experiments demonstrated that in the treated animals, the bone defects were filled with biomaterial particles, granulation tissue and some areas of newly formed bone. Furthermore, similar immunoexpression of Runx-2 and Cox-2 was observed. Taken together, all results suggest that PE is biocompatible, present non-citotoxicity in the in vitro studies (at the lower concentration) and in the in vivo studies and it can be considered as an alternative source of collagen for tissue engineering proposals.

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Abstract This study characterized the morphological aspects of marine collagen - spongin (SPG) extract from marine sponges, as well as, evaluating its in vitro and in vivo biological performance. Aplysina fulva marine sponge was used for the SPG extraction. It was investigated the physicochemical and morphological properties of SPG by using scanning electron microscopy, Fourier transform infrared spectroscopy, X-ray diffraction and compared to PMMA and bovine collagen. Additionally, the SPG cytotoxicity and its influence on cell proliferation, through in vitro tests. Moreover, the in vivo biological response was investigated using an experimental model of tibial bone defect. The results demonstrated that SPG presented an irregular granular aspect, with a composition of OH, C=O, NH, CN and an amorphous profile. Also, in vitro viability results for the L929 and MC3T3 cell lines cultured with SPG extracts demonstrated normal growth in comparison to controls, except for MC3T3 viability at day 3. For in vivo analysis, using tibial bone defects in rats, SPG treated animals presented an increased rate of material resorption and higher granulation and bone formation deposition in the region of the defect, mainly after 45 days. As a conclusion, SPG was successfully extracted. The in vitro and in vivo studies pointed out that SPG samples produced an increase in L929 and MC3T3 viability and improved the performance in tibial bone defects. It can be concluded that SPG can be used as a bone graft for bone regeneration.

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This study evaluated the physicochemical and morphological properties of a marine sponge protein extract (PE) using scanning electron microscopy (SEM), Energy dispersive X-ray spectroscopy (EDS), analysis of mass loss and pH and in vitro and in vivo. Scanning electron microscopy showed that PE fibers present a granular aspect and irregular structure and the element carbon followed by oxygen was detected in the EDS analysis. Moreover, a 29% of mass loss was observed after 14 days and the pH slightly modified after 14 days. Cell viability of fibroblast cells (L929) of control and PE at a concentration of 25% demonstrated higher values compared to the groups. Osteoblast cell viability of PE at 25 and 50% was significantly higher. Comet assay on day 1 showed higher values for PE at 25%. In addition, in vivo experiments demonstrated that in the treated animals, the bone defects were filled with biomaterial particles, granulation tissue and some areas of newly formed bone. Furthermore, similar immunoexpression of Runx-2 and Cox-2 was observed. Taken together, all results suggest that PE is biocompatible, present non-citotoxicity in the in vitro studies (at the lower concentration) and in the in vivo studies and it can be considered as an alternative source of collagen for tissue engineering proposals.(AU)

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One of the most promising strategies to improve the biological performance of bone grafts is the combination of different biomaterials. In this context, the aim of this study was to evaluate the effects of the incorporation of marine spongin (SPG) into Hydroxyapatite (HA) for bone tissue engineering proposals. The hypothesis of the current study is that SPG into HA would improve the biocompatibility of material and would have a positive stimulus into bone formation. Thus, HA and HA/SPG materials were produced and scanning electron microscopy (SEM) analysis was performed to characterize the samples. Also, in order to evaluate the in vivo tissue response, samples were implanted into a tibial bone defect in rats. Histopathological, immunohistochemistry, and biomechanical analyses were performed after 2 and 6 weeks of implantation to investigate the effects of the material on bone repair. The histological analysis demonstrated that composite presented an accelerated material degradation and enhanced newly bone formation. Additionally, histomorphometry analysis showed higher values of %BV/TV and N.Ob/T.Ar for HA/SPG. Runx-2 immunolabeling was higher for the composite group and no difference was found for VEGF. Moreover, the biomechanical analysis demonstrated similar values for all groups. These results indicated the potential of SPG to be used as an additive to HA to improve the biological performance for bone regeneration applications. However, further long-term studies should be carried out to provide additional information regarding the material degradation and bone regeneration.

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Abstract Research on biomaterials of natural origin has gained prominence in the literature. Above all, marine sponges, due to their architecture and structural components, present a promising potential for the engineering of bone tissue. In vitro studies demonstrate that a biosilica of marine sponges has osteogenic potential. However, in vivo works are needed to elucidate the interaction of biosilica (BS) and bone tissue. The objective of the study was to evaluate the morphological and chemical characteristics of BS compared to Bioglass (BG) by scanning electron microscopy (SEM) and X-ray dispersive energy (EDX) spectroscopy. In addition, to evaluate the biological effects of BS, through an experimental model of tibial bone defect using histopathological, histomorphometric, immunohistochemical (IHC) and mechanical tests. SEM and EDX demonstrated the successful extraction of BS. Histopathological analysis demonstrated that Control Group (GC) had greater formation of newly formed bone tissue compared to BG and BS, yet BG bone neoformation was greater than BS. However, BS showed material degradation and granulation tissue formation, with absence of inflammatory process and formation of fibrotic capsule. The results of histomorphometry corroborate with those of histopathology, where it is worth emphasizing the positive influence of BS in osteoblastic activity. IHQ demonstrated positive VEGF and TGF-β immunoexpression for GC, BS and BG. In the mechanical test no significant differences were found. The present results demonstrate the potential of BS in bone repair, further studies are needed other forms of presentation of BS are needed.

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Metal contamination exerts environmental pressure on several lifeforms. Since metals are non-biodegradable and recalcitrant, they accumulate in living beings and spread through the food chain. Thus, many life forms are affected by environmental metal contamination, such as plants and microorganisms. In the case of microorganisms, scarce information is available on how metals affect them. As a highly resistant form of life, microorganisms can adapt to several environmental pressures through genetic modifications, changing their metabolism to overcome new conditions, and continuing to thrive in the same place. In this study, an Acinetobacter sp. strain was isolated from a copper mine, which presented very high resistance to copper, growing in copper concentrations of up to 7 mM. As a result of its metabolic response in the presence of 3 mM of copper, the expression of 35 proteins in total was altered. The proteins were identified to be associated with the glycolytic pathway, membrane transport, biosynthesis and two proteins directly involved in copper homeostasis (CopA and CopB).

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This study evaluated physical-chemical characteristics of a vacuumed collagen-impregnated bioglass (BG) scaffolds and bone marrow stromal cells (BMSCs) behavior on those composites. scanning electron microscope and energy dispersive x-ray spectroscope demonstrated collagen (Col) was successfully introduced into BG. Vacuum impregnation system has showed efficiency for Col impregnation in BG scaffolds (approximately 20 wt %). Furthermore, mass weight decreasing and more stabilized pH were observed over time for BG/Col upon incubation in phosphate buffered saline compared to plain BG under same conditions. Calcium evaluation (Ca assay) demonstrated higher calcium uptake for BG/Col samples compared to BG. In addition, BG samples presented hydroxyapatite crystals formation on its surface after 14 days in simulated body fluid solution, and signs of initial degradation were observed for BG and BG/Col after 21 days. Fourier transform infrared spectroscopy spectra for both groups indicated peaks for hydroxyapatite formation. Finally, a significant increase of BMSCs viability for both composites was observed compared to control group, but no increase of osteogenic differentiation-related gene expressions were found. In summary, BG/Col scaffolds have improved degradation, pH equilibrium and Ca mineralization over time, accompanied by hydroxyapatite formation. Moreover, both BG and BG/Col scaffolds were biocompatible and noncytotoxic, promoting a higher cell viability compared to control. Future investigations should focus on additional molecular and in vivo studies in order to evaluate biomaterial performance for bone tissue engineering applications. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 107B: 211-222, 2019.

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Copper mining has polluted soils and water, causing a reduction of the microbial diversity and a change in the structure of the resident bacterial communities. In this work, selective isolation combined with MALDI-TOF MS and the 16S rDNA method were used for characterizing cultivable bacterial communities from copper mining samples. The results revealed that MALDI-TOF MS analysis can be considered a reliable and fast tool for identifying copper-resistant bacteria from environmental samples at the genera level. Even though some results were ambiguous, accuracy can be improved by enhancing reference databases. Therefore, mass spectra analysis provides a reliable method to facilitate monitoring of the microbiota from copper-polluted sites. The understanding of the microbial community diversity in copper-contaminated sites can be helpful to understand the impact of the metal on the microbiome and to design bioremediation processes.

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In this study, an effective microbial consortium for the biodegradation of phenol was grown under different operational conditions, and the effects of phosphate concentration (1.4 g L(-1), 2.8 g L(-1), 4.2 g L(-1)), temperature (25 degrees C, 30 degrees C, 35 degrees C), agitation (150 rpm, 200 rpm, 250 rpm) and pH (6, 7, 8) on phenol degradation were investigated, whereupon an artificial neural network (ANN) model was developed in order to predict degradation. The learning, recall and generalization characteristics of neural networks were studied using data from the phenol degradation system. The efficiency of the model generated by the ANN was then tested and compared with the experimental results obtained. In both cases, the results corroborate the idea that aeration and temperature are crucial to increasing the efficiency ofbiodegradation.

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