Resorbable GBR Scaffolds in Oral and Maxillofacial Tissue Engineering: Design, Fabrication, and Applications.

Guided bone regeneration (GBR) is a promising technique in bone tissue engineering that aims to replace lost or injured bone using resorbable scaffolds. The promotion of osteoblast adhesion, migration, and proliferation is greatly aided by GBR materials, and surface changes are critical in imitating the natural bone structure to improve cellular responses. Moreover, the interactions between bioresponsive scaffolds, growth factors (GFs), immune cells, and stromal progenitor cells are essential in promoting bone regeneration. This literature review comprehensively discusses various aspects of resorbable scaffolds in bone tissue engineering, encompassing scaffold design, materials, fabrication techniques, and advanced manufacturing methods, including three-dimensional printing. In addition, this review explores surface modifications to replicate native bone structures and their impact on cellular responses. Moreover, the mechanisms of bone regeneration are described, providing information on how immune cells, GFs, and bioresponsive scaffolds orchestrate tissue healing. Practical applications in clinical settings are presented to underscore the importance of these principles in promoting tissue integration, healing, and regeneration. Furthermore, this literature review delves into emerging areas of metamaterials and artificial intelligence applications in tissue engineering and regenerative medicine. These interdisciplinary approaches hold immense promise for furthering bone tissue engineering and improving therapeutic outcomes, leading to enhanced patient well-being. The potential of combining material science, advanced manufacturing, and cellular biology is showcased as a pathway to advance bone tissue engineering, addressing a variety of clinical needs and challenges. By providing this comprehensive narrative, a detailed, up-to-date account of resorbable scaffolds' role in bone tissue engineering and their transformative potential is offered.

The immune response against Toxoplasma gondii in BALB/c mice induced by mannose-modified nanoliposome of excreted/secreted antigens.

This study aimed to compare the immune response against Toxoplasma gondii (T. gondii) in BALB/c mice induced by excreted/secreted (E/S) antigens and mannose-modified nanoliposome of E/S antigens. Here, E/S antigens and mannose-modified nanoliposome of E/S antigens were firstly prepared, and then BALB/c female inbred mice were separately immunized. In the next step, anti-E/S antigen antibodies and the relative expression levels of IL-10 and IL-12 mRNA were detected by ELISA and real-time PCR, respectively. After immunization, mice were intraperitoneally challenged with 102 tachyzoites of T. gondii, and the survival rate was recorded. The ELISA analysis showed significant differences between the levels of anti-E/S antigen antibodies in the mice immunized by E/S antigens and those immunized by mannose-modified nanoliposome of E/S antigens at days 7, 10, 20, 25, and 30 (P < 0.05). Real-time PCR analysis showed that the relative expression of IL-10 was significantly decreased during 20 days. Yet, the relative expression of IL-12 was significantly increased during 20 days (P < 0.05). In T. gondii challenge test, significant differences were found between the survival rates of mice immunized by E/S antigens and mice immunized by mannose-modified nanoliposome with E/S antigens. This project evidenced that mannose-modified nanoliposome of E/S antigens induced a more powerful immune response against T. gondii in BALB/c mice when compared with excreted/secreted antigens alone.

A Review Study about the Effect of Chitosan Nanocarrier on Improving the Efficacy of Amphotericin B in the Treatment of Leishmania from 2010 to 2020.

In the present review study, the published articles from 2010-2020 that evaluated the effect of chitosan nanocarrier on the efficacy of amphotericin B (AmB) in the treatment of leishmaniasis, have been considered. Leishmania is a parasitic tropical disease in the world and is treated with AmB as one of the main therapeutic agents. However, the clinical application of AmB is limited due to its toxicity and insolubility issues. Using nanoparticles and, in particular, chitosan, nanocarrier seems a promising approach to overcome these problems. Therefore, various doses of AmB have been loaded in chitosan nanoparticles in different studies and the results of these studies demonstrated that by increasing the drug loading efficiency and decreasing the toxicity, the potency of the nanoformulation to inhibit and to kill the parasite is increased. In this regard, the results of a study performed in 2018, demonstrated that chitosan nanoparticles with the higher dose of drug loading were the most effective formulation to inhibit and kill the parasite. Thus, chitosan nanocarrier can consider as an appropriate candidate in the future to inhibit and kill the Leishmania parasite without causing side effects.

Preparation, Characterization, and Evaluation of Cisplatin-Loaded Polybutylcyanoacrylate Nanoparticles with Improved In Vitro and In Vivo Anticancer Activities.

This study aimed to evaluate the therapeutic efficacy of the cisplatin encapsulated into polybutylcyanoacrylate (PBCA) nanoparticles for the treatment of kidney cancer. The nanoformulation was successfully developed using the miniemulsion polymerization method and characterized in terms of size, size distribution, drug loading and encapsulation efficiencies, drug release behavior, in vitro cytotoxicity effects, in vivo toxicity, and therapeutic effects. Cisplatin-loaded PBCA nanoparticles were confirmed to be in nanoscale with the drug entrapment efficiency of 23% and controlled drug release profile, in which only 9% of the loaded drug was released after 48 h. The nanoparticles caused an increase in the cytotoxicity effects of cisplatin against renal cell adenocarcinoma cells (ACHN) (2.3-fold) and considerably decreased blood urea nitrogen and creatinine concentrations when compared to the standard cisplatin (1.6-fold and 1.5-fold, respectively). The nanoformulation also caused an increase in the therapeutic effects of cisplatin by 1.8-fold, in which a reduction in the mean tumor size was seen (3.5 mm vs. 6.5 mm) when compared to the standard cisplatin receiver rats. Overall, cisplatin-loaded PBCA nanoparticles can be considered as a promising drug candidate for the treatment of kidney cancer due to its potency to reduce the side effects of cisplatin and its toxicity and therapeutic effects on cancer-bearing Wistar rats.

Effect of gold nanoparticles on properties of nanoliposomal hydroxyurea: an in vitro study.

New hopes in cancer treatment have been emerged using functional nanoparticles. In this work, we tried to synthesize gold nanoparticles and gold nanoparticles conjugated with DNA extracted from human breast cancer cells. After synthesizing, gold nanoparticles were mixed with nanoliposomal hydroxyurea and corresponding compounds were formed. They were described by UV-Visible spectrophotometry and Zeta sizer. Amount of drug loading into liposomes was determined by spectrophotometry and cytotoxicity effect on MCF-7 cells was measure by MTT assay. Drug loading was determined to be 70 %. Size, size distribution and Zeta potential of particles were 473 nm, 0.46 and -21 mV for control nanoliposomal ones and 351 nm, 0.38 and -25 mV for nanoliposomal particles containing hydroxyurea. This was 29 nm, 0.23 and -30 mV for gold nanoparticles and 502 nm, 0.41 and -38 mV for nanoliposomes containing drug loaded by gold nanoparticles conjugated with DNA. It was found that nano conjugated complex in concentrations less than 20 µM of hydroxyurea can improve efficiency compared with liposomal drug. In maximum concentration of drug (2,500 µM), cytotoxicity was equal to 95 %. In minimum concentration of drug (5 µM), cytotoxicity of liposomal drug and conjugated complex were 70 and 81 %, respectively which probably comes from increased drug entry into cells due to the presence of gold nanoparticles. Free drug resulted in toxicity of 32 % in 5 µM and 88 % in 2,500 µM. Results demonstrated higher drug efficiency in nanoparticle form compared with free form which can be used in in vivo studies.

An investigation into the parameters affecting preparation of polybutyl cyanoacrylate nanoparticles by emulsion polymerization.

Emulsion polymerization was used to synthesize poly butyl cyanoacrylate nanoparticles in presence of steric stabilizer dextran 70. Nanoparticles were characterized by particle size analysis, scanning electron microscopy and light microscopy. Polymerization factors affecting particle size and distribution such as dextran 70, polysorbate 80 (PS 80) and H(+) concentration, polymerization time and temperature, and sonication were studied. Distinct concentrations of stabilizer were needed to produce proper nanoparticles. In this case, the appropriate value was 2 % of total volume. At pH 4 significant decrease in production efficiency demonstrated the substantial effect of H(+) concentration on nanoparticles. Furthermore significant increases in particle size and distribution was observed at 50 °C compared to room temperature. 0.001 % (v/v) PS 80 represented notable influence on size and distribution. In addition, shaped nanoparticles were obtained by altering polymerization time from 5.5 h to 18 h. Finally, nanoparticle features were influenced by different factors. Appropriate manipulating of such factors can lead to obtaining desirable nanoparticles.

Effect of sodium chloride on efficiency of cisplatinum dissolved in dimethyl sulfoxide: an in vitro study.

Cisplatinum (Cispt) is an anti-cancer drug with a low level of solubility. One of Cispt's solvents is dimethyl sulfoxide (DMSO) which can be substituted with chlorine of drug as Cispt's solvent. Applying such a solvent in biological studies is impossible due to intense reduction in activity. On the other hand, it is specified that Cispt's stability is increased in aqueous media by increasing sodium chloride (NaCl) concentration up to 0.9 %. Consequently, we intended to study the effect of DMSO on cytotoxicity of Cispt in presence of sodium. MTT assay was employed to study cytotoxicity effect of Cispt + NaCl + DMSO and Cispt + DMSO on G-292 cell line. Cytotoxicity in dilutions of 300 and 9 (p < 0.01) of Cispt in Cispt + NaCl + DMSO formulation was equal to 78 and 7 %. These values were estimated 79 and 18 % for Cispt + DMSO formulation and 79 and 24 % for free drug. IC50 values demonstrated reduction of 45 % in cytotoxicity of Cispt in Cispt + DMSO formulation. Studying chemical structure of Cispt and Cispt dissolved in DMSO showed that NaCl cannot inhibit inactivating effect of DMSO on Cispt and effect of this solvent on Cispt is independent from presence of NaCl. Results represented that using NaCl does not result in stability and keeping cytotoxicity properties of Cispt in DMSO. Findings suggest more studies for using DMSO as a solvent of Cispt.