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To flourish new applications at a low cost to the environment, it is important to develop non-toxic eco-friendly ferromagnetic single-phase zinc oxide (ZnO) nanoparticles with nickel (Ni2+) doping. The titled materials were prepared using an easy and rapid solution combustion synthesis method. XRD, SEM, and TEM were used to figure out the structure and morphology of as-synthesized materials, which confirmed the nanoscale ZnO structure in a single phase. The sample shows a single phase with nickel metal incorporated into the Wurtzite crystal structure of ZnO by replacing the Zn2+. The ferromagnetic behavior of the as synthesized samples was observed at room temperature. The ferromagnetic exchange coupling between the doped Ni2+ ions facilitate the ferromagnetic behavior, and the magnetic saturation is increased with the Ni2+ doping. As-synthesized samples were shown to have photocatalytic activity. The incorporation of nickel ions in the ZnO structure facilitated the enhancement of the catalytic activity. The improved catalytic activity is attributed to the band gap tuning of the ZnO, which favors the improved degradation of the Methylene Blue dye under a UV light source. The prepared samples pave the way for recyclable photo-catalysis applications of ZnO, which can be easily separated using a permanent magnet.

In this chapter, a modest attempt has been made to study the heavy metal contamination including their bio-accumulation and toxic effects in our daily lives. It is the alarming hazards to the environment, especially in the industrial zones, that confirm the attention paid to these contaminants. The authors tried to determine the content of heavy metals (cadmium - Cd, lead - Pb, copper - Cu, zinc - Zn, nickel - Ni, manganese – Mn, and chromium - Cr) in the individual samples of cow milk from the farms in seven different localities. The distribution and dynamics of the determined heavy metals in the milk were recorded at different distances starting from the area of the industrial capacity. All the milk samples were analyzed properly, and the authors did chemical consumption and somatic cells and bacteria inside them. The findings were found within good agreements with others.

The development of natural-based wound dressings is of great interest in the field of skin tissue engineering. Herein, different bioactive molecules such as gelatin (GEL), chitosan (CH) and mucilage (MU) were used to prepare a wound dressing. The physico-chemical and biological characterizations occurring after γ-irradiation were investigated. Results showed that Electron Paramagnetic Resonance (EPR) spectroscopy of un-irradiated GEL-CH-MU biomaterial showed two paramagnetic centers which correspond to g = 1.89 and g = 2.033. A generated new active center appeared at g = 2.003 at 25 kGy due to the interactions of gamma rays with the polymer chain creating signals at the absorbing functional groups. X-ray diffraction (XRD) spectra preserved the semi-crystalline structures between a range of 2θ (5° and 45°). Fourier Transform Infrared spectroscopy (FTIR) revealed that the initiation of cross linking phenomena. Moreover, γ-rays significantly increased antioxidant activity (9.1 ± 0.07%, p

Biodegradable films from gelatin (Gn) with various date by-product (DBP) concentrations (1, 2, 3 and 4 wt %) were prepared. Elaborated films were examined in terms of physical properties (thickness, density, water solubility, water content, degree of swelling, color), and antimicrobial properties (Escherichia coli and Staphylcoccus aureus). Adding the highest concentration of DBP (4%), resulted an increase in the WHC of film as compared with control film. Moreover, the incorporation of 1% DBP reduced the moisture level of Gn based composite films as compared with the control film. Furthermore, Film with 4% of DBP had the lowest solubility which reached 39.39%. Incorporation of DBP from 1 to 4% showed decrease of L- and a-values. The active Gn-DBP 1% showed less lightness as compared to Gn-DBP 3%. The incorporation of DBP into film-forming solutions led to increased opaqueness for all gelatin-based composite films. The calculated opacity value was inversely proportional to transparency. Moreover, the Active Gn-DBP 1% and 2% film presented effective antibacterial activity against bacteria such as Staphylococcus aureus and Escherichia coli. The results showed an enhancement in the biodegradability of Gn-DBP films in moist soil. The results reveal the benefits of date by-products incorporated into gelatin based films as a potential material for active food packaging.

Aims The present study investigates the effectiveness of platelet-rich plasma (PRP) gel without adjunct to induce cartilage regeneration in large osteochondral defects in a rabbit model. Methods A bilateral osteochondral defect was created in the femoral trochlear groove of 14 New Zealand white rabbits. The right knees were filled with PRP gel and the contralateral knees remained untreated and served as control sides. Some animals were killed at week 3 and others at week 12 postoperatively. The joints were harvested and assessed by Magnetic Resonance Observation of Cartilage Repair Tissue (MOCART) MRI scoring system, and examined using the International Cartilage Repair Society (ICRS) macroscopic and ICRS histological scoring systems. Additionally, the collagen type II content was evaluated by the immunohistochemical staining. Results After 12 weeks post-surgery, the defects of the PRP group were repaired by hyaline cartilage-like tissue. However, incomplete cartilage regeneration was observed in the PRP group for three weeks. The control groups showed fibrocartilaginous or fibrous tissue, respectively, at each timepoint. Conclusion Our study proved that the use of PRP gel without any adjuncts could successfully produce a good healing response and resurface the osteochondral defect with a better quality of cartilage in a rabbit model. Cite this article: Bone Joint Res 2021;10(3):192–202.

Britholites derivatives of apatite’s that contain lanthanium and neodymium in the serial compounds Sr8La2−xNdx(PO4)4(SiO4)2F2 with 0 ≤ x ≤ 2 were subject of the present investigation. The solid state reaction was the route of preparing these materials. Several techniques were employed for the analysis and characterization of the synthesized powders. The chemical analysis results indicated that molar ratio Sr+La+NdP+Si was of about 1.67 value of a stoichiometric powder. The X-ray diffraction data showed single-phase apatites crystallizing in hexagonal structure with P63/m space group were successively obtained. Moreover, the substitution of lanthanium by neodymium in strontium phosphosilicated fluorapatite was total. This was confirmed by the a and c lattice parameters contraction when (x) varies coherently to the sizes of the two cations. The infrared spectroscopy and the 31P NMR (MAS) exhibited the characteristic bands of phosphosilicated fluorapatite. The pressureless sintering of the material achieved a maximum of 89% relative density. The sintered specimens indicated that the Nd content as well as the heating temperature affected the ionic conduction of the materials and the maximum was 1.73 × 10−6 S cm−1 obtained at 1052 K for x = 2.

In this paper, we focus on the camelid nanobodies as a revolutionary therapy that can guide efforts to discover new drugs for Coronavirus disease (COVID-19). The small size property makes nanobodies capable of penetrating efficiently into tissues and recognizing cryptic antigens. Strong antigen affinity and stability in the gastrointestinal tract allow them to be used via oral administration. In fact, the use of nanobodies as inhalant can be directly delivered to the target organ, conferring high pulmonary drug concentrations and low systemic drug concentrations and minimal systemic side effects. For that, nanobodies are referred as a class of next-generation antibodies. Nanobodies permit the construction of multivalent formats that may achieve ultra-high neutralization potency and then may prevent mutational escape and can neutralize a wide range of SARS-CoV-2 variants. Due to their distinctive characteristics, nanobodies can be of great use in the development of promising treatment or preventive strategies against SARS-CoV-2 infection. In this review, the state-of-the-art of camel nanobodies design strategies against the virus including SARS-CoV-2 are critically summarized. The application of general nanotechnology was also discussed to mitigate and control emerging SARS-CoV-2 infection.

International audience; The damage to normal bone tissue following therapeutic irradiation increases the risk of fracture and bone osteoporosis. Bioactive glasses have been synthesized with improved properties exhibiting promising prospects to restore bone defects and to reduce bone alterations. This study aims in evaluating the performance therapy of nano-bioglass (NBG). In vivo, after rat Co-60 y-radiation, the tissue wound healing process was studied by grafting NBG material in rat femoral condyle tissue. An improved mechanical property was noticed (31.11 +/- 5.0 HV) when compared with that of BG-implanted group (24.16 +/- 4.9 HV). On the other hand, a rise in Ca and P ion concentrations in the implanted microenvironment was shown to lead to the formation/deposition of Ca-P phases. Trace elements, such as Mg and Zn, were detected in the newly formed bone and involved in bone healing. Serum alanine aminotransferase (ALT), aspartate transaminase (AST), and gamma-glutamyl-transpeptidases (GTT) in groups implanted with NBG show no significant variation for all time of implantation. Serum creatinine maintains their normal levels in the implanted groups in different time of implantation. The histomorphometric parameters of bone tissue showed amelioration in NBG-treated rats. Moreover, no hepatocyte or renal necrosis was noticed. Additionally, no remarkable change in the tissue morphology was shown. Our findings suggested that NBG might have promising potential applications for wound healing.

International audience; Recently, oxidative stress has been identified as a pivotal pathological factor inducing bone osteoporosis. This phenomenon is responsible for low bone density. It alters bone quality and generates bone fractures. Strontium is found to induce osteoblast activity by stimulating bone formation and reducing bone resorption by restraining osteoclasts. Bioglass (BG) has been used to repair bone defects, and, in combination with strontium (BG-Sr), offers an opportunity to treat this disease. This study investigated the potential role of BG-Sr in improving antioxidant activity and regenerative bone capacity, The effects of both BG-Sr and BG were tested on osteoblast SaOS2 and endothelial EAhy926 cell proliferation in vitro. In vivo, BG-Sr and BG were implanted in the femoral condyles of Wistar rats and compared to that of control groups. Cell proliferation increased significantly by 120% at SaOS2 and 127% at EAhy926. Superoxide Dismutase (SOD), Catalase (CAT) and Glutathione Peroxidase (GPx) were significantly enhanced in BG-Sr treated rats compared to other groups. Moreover, a significant decrease of thiobarbituric acid-reactive substances (TBARs) was observed. The Ca/P ratio increase improved progressive bone mineralization. According to these results, BG-Sr ameliorated cell proliferation and developed an antioxidative defense against ROS. The histological findings highlight the BG-Sr implications in the osteoporosis treatment confirmed by bone construction. The development of BG-Sr as a therapeutic biomaterial protecting against oxidative stress might make an effective choice for application in tissue engineering.

The ameliorative effects of Opuntia vulgaris fruit extract (OE) were evaluated against methanol-induced haematological and biochemical toxicity in rats. The methanol-induced haematological and biochemical perturbation significantly decreased the levels of red blood cell (RBC), haemoglobin (Hb), haematocrit (Ht), serum total protein and increased glucose, cholesterol, and triglyceride levels in serum. Treatment of rats with methanol significantly increased lipid peroxidation (LPO) level and decreased the activities of superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx) in erythrocytes. OE treatment could increase significantly the levels of RBC, Hb, Ht and total protein, and decrease glucose, cholesterol and triglyceride levels in serum, and increase the activities of SOD, CAT and GPx in erythrocytes, when compared with methanol-treated group. Spleen histopathology showed that OE could significantly reduce the incidence of spleen lesion induced by methanol. These results suggested that OE could exhibit a potential source of natural antioxidants against methanol-induced haematological and biochemical disruption in rats. The protective effects of OE may be due to the modulation of antioxidant enzymes activities and inhibition of LPO.

Bone loss associated with skeletal trauma or metabolic diseases often requires bone grafting. In such situations, a biomaterial is necessary for migrated cells to produce new tissue. In this study, agarose–chitosan was implanted in the femoral condyle of New Zealand White rabbits that were divided into three groups: Group I was used as control; Groups II and III were used as implanted tissue with agarose–chitosan and presenting empty defects, respectively. This study evaluated the agarose–chitosan biocompatibility by determining the in vivo genotoxicity, oxidative stress balance that correlated with the hardness mechanical property. Moreover, the histopathological and quantitative elements analyzed by using inductively coupled plasma optical emission spectrometry were determined. After 30 days of implantation, the in vivo analysis of genotoxicity showed that agarose–chitosan did not induce chromosome aberration or micronucleus damage. A significant decrease in thiobarbituric and acid-reactive substance was observed after agarose–chitosan implantation in the bone tissue. Superoxide dismutase, catalase and glutathione peroxidase were significantly enhanced in agarose–chitosan–treated group compared with that of control group. A negative correlation coefficient of the mechanical property with malonyldialdehyde level was detected (R = −0.998). The histological study exhibited a significantly increased angiogenesis and newly formed tissue. No presence of inflammatory process, necrotic or fibrous tissue was detected. Major and trace elements such as Ca, P, Zn, Mg and Fe were increased significantly in the newly formed bone. These findings show that agarose–chitosan biomaterial implantation might be effective for treating trauma and bone regeneration.

Chitosan (CH) material reinforced by bioactive glass (46S6) was fabricated. 46S6 containing 17% wt% CH was studied in vitro and in vivo. Physicochemical techniques, such as Fourier transform infrared spectroscopy (FT-IR), coupled plasma optical emission spectrometry (ICP-OES) analysis were used. The behavior of 46S6CH17 was studied by measuring the in situ pH in a SBF solution. The 46S6CH17 was implanted in the rat femoral condyl. In vitro 46S6CH17 gave an FTIR - spectrum in which three absorption bands with the maxima at 565, 603 and 1039cm-1 after 3 days of soaking in physiological solution. They are assigned to stretching vibrations of PO4^3- group in phosphate crystalline. Moreover, the pH measurement was decreased in the SBF solution. The stability of the calcium phosphate precipitation depended on the pH value. In vivo, a rise in the Ca and phosphate P ions concentrations in the implanted microenvironment was determined., {"references":["R.A. Muzzarelli, F. Tanfani, M. 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International audience; Orthopedic devices are used in pathologic disorder as an adjunct to bone grafts to provide immediate structural stability. Unfortunately, the use of metallic devices has some complications. This study aimed to characterize the oxidative stress biomarker and the antioxidant enzyme profiles during bone regeneration. New Zealand White rabbits were divided into 4 groups: Group (I) was used as control (T), Groups II, III, and IV were used, respectively, as implanted tissue with carbonated hydroxyapatite (CHA), carbonated hydroxyapatite associated with external fixator (CHA + EF), and presenting empty defects (ED). Grafted bone tissues were carefully removed to measure malondialdehyde (MDA) concentration, superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase activities (GPx). Our results showed that 4 weeks after operation, treatment of rabbits with CHA + EF showed a significantly higher malondialdehyde (MDA) concentration when compared to that of control group. The SOD, CAT, and GPx in CHA + EF group showed significantly lower activities when compared to those in control group. Eight weeks after surgery, the CHA + EF group presented a lower concentration of MDA as compared to those seen after the first 4 weeks after surgery. On the other hand, the SOD, CAT, and GPx showed a higher activity when compared with the same group. Consequently, MDA concentration and the antioxidant enzyme activities were not significant (p > 0.05) when compared to those in control group rabbits. Histologic sampling has demonstrated successful time-patterned resorption accompanied by bone replacement and remodeling. These results suggest that there was a temporary increase in the oxidative marker level in CHA + EF healing bone and the 8-week period was sufficient to re-establish oxidant-antioxidant balance accompanied by bone repair in the tibia rabbit model.

Bone loss associated with skeletal trauma or metabolic diseases often require bone grafting. The present study aimed to evaluate the performance of bioactive glass-chitosan composite (BG-CH) produced by a freeze-drying process. BG containing 17% wt% CH was implanted in the femoral condyl of an ovariectomised rat. The resected bone was prepared for analysis using several physico-chemical techniques such as fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy-dispersive X-ray (EDX). After 2 weeks, the implanted sample gave a spectrum in which two pronounced absorption bands with the maxima at 932 and 1036 cm-1 arising from (Si-O-Si) groups disappeared 15 days after surgery. These bands were replaced 30 days after implantation by 601 and 564 cm-1(P- O) arisen form bone apatite bands. After 4 weeks, peaks at 31.6 and 25.8° (2θ) were registered thus inducing a degradation of BG-CH which occurred simultaneously with the implant replacement by the bone cells. Our data showed that the incorporation of 17% wt% CH with BG matrix promoted a highly significant bioactivity and generated an osteoinductive property. These effects might make BG-CH an effective biomaterials choice for the biomedical field. Key words: Chitosan-glasses, biominiralisation, osteoinductivity, biomedical applications, bone defect healing.

Developmental pathology, accidents, and tumor resection frequently cause bone loss,1,2 which is still a problem in orthopedic and reconstructive surgery. To resolve these problems, autografts and allografts have long been used to fill bone defects caused by surgery, trauma or disease.3 Autografts have the advantage of being biocompatible, osteoconductive and osteoinductive. These tissue grafts require additional surgery, which can cause trauma and donor site morbidity that leads to an increase in surgical time and hospital costs.4 Allografts overcome these problems, but can potentially introduce the risk of transmission infection or provoke an immunogenic response. To overcome these problems, a variety of osteoconductive biomaterials such as ceramics and titanium alloys have been considered as bone graft substitutes.5 Titanium (Ti), which is bioinert, does not bond directly but has close contact with bone. Other synthetic bone grafts are made from biphasic calcium phosphates, and beta-tricalcium phosphate, calcium polyphosphate, hydroxyapatite (HA),6 and carbonated hydroxyapatite (CHA). Recently, osteoconductive biomaterials suggest that they can be made in greater quantities and present no immunogenic concerns.7 These biomaterials have gained much attention, not only due to its ionic composition similar to bones but also due to its functional properties favorable for bone growth such as resorbability by living cells.8 Moreover, some investigators have reported that HA is useful as an osteoporosis model. The present study was undertaken to evaluate the regenerative effects of both CHA and mini external fixator in large cortical defect. The utilization of these materials as bone grafts may reduce the need for autogenous bone graft, increase stability of the implant, lead to faster bone regeneration and facilitate the healing process.