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In the present study, pure chitosan and gelatin solutions are blended at four various ratios with the addition of Fluorohydroxyapatite (FHA). The specimens are fed into the Freeze-Drying (FD) apparatus to produce porous architectures. The X-ray Diffraction (XRD) and the Scanning Electron Microscopy (SEM) are used for analyzing the solutions and finding the best solution regarding the number of beads and droplets, yielded fibers, and morphological uniformity. The flow rate, voltage, and distance from the needle to the collector are variate in the selected specimen for examining the impact processing parameters on fibers morphology and nanofibers diameter. The in-vitro biocompatibility examination is executed with human skin fibroblasts to distinguish the cell proliferation level on the scaffolds. The results obtained by XRD and SEM confirmed that the specimen containing 70% and 30% chitosan and gelatin, respectively, includes the minimum number of beads, droplets, yielded fibers, and the maximum morphological uniformity. Then, the in-vitro biocompatibility tests confirmed high and acceptable biological properties for the specimen. For more details, the experimental tests report that S1 has the maximum displacement value of 207.64 nm, while S4 represents the lowest displacement value of 175.87 nm. Moreover, the numerical study indicated that the scaffold compressive strength increases from 22.8 MPa (S1) to 31.2 MPa (S4) with the addition of 30 wt % FHA nanoparticles. Nanoindentation finite element simulation proved that the indenter penetration decreases from 215.54 nm to 181.46 nm with the addition of 30 wt % FHA nanoparticle. As a consequence, Chitosan-gelatin/FHA/30 wt % FHA (S4), has the best mechanical properties.

The octamer-binding transcription factor-4 (OCT4) is known as an established important regulator of pluripotency, as well as a genetic "master switch" in the self-renewal of embryonic stem and germ cells.The present study developed a transgenic mouse model containing anTheThe results demonstrated the changes in sperm morphology, as well as a statistically significant decrease in the other sperm parameters (count, viability, and motility) and fertility rate (p0.05) in the transgenic mice compared with the control group. The assessment of the cause of the embryonic stem cell (ESC) death following transfection revealed a significant reduction in the endogenous OCT4 expression at both mRNA and protein levels in the transfected mESCs compared to the control ones.In general, the

Inflammatory processes activated by rapid viral replication of SARS-CoV-2 can play a key role in the pathogenesis of multiple organ damage and be responsible for the COVID-19 patients' dramatic outcomes and common abnormal laboratory findings. The aim of this study was to assess the correlation between various laboratory biomarkers, ferritin/transferrin ratio (FTR) and receiver operating characteristic (ROC) analysis in monitoring COVID-19 patients.This observational study was conducted in three groups: healthy participants, non COVID-19 patients with COVID-19-like clinical signs, and COVID-19 patients (severe and non-severe). Biochemical (CRP, ferritin, transferrin and albumin) and hematological (WBC, lymphocytes) parameters were assessed by automated methods. Moreover, FTR and NLR markers were calculated in the three groups mentioned. Statistical analyses were done using R (version 4.1.0). ROC curve was used to validate the predictive value of parameters.The COVID-19 positive group had significantly higher NEU, CRP, ferritin, FTR values, while it's WBC, absolute counts of lymphocytes and albumin were significantly lower compared to the non-COVID-19 patients (p0.001). Serum ferritin and FTR level of the severe group was significantly higher than that of the non-severe group (p = 0.006 and (p = 0.011, respectively). The strongest correlation in all subjects showed between lymphocytopenia and increased NEU (r = -0.99, p0.001). The AUC values of WBC (0.95), lymphocytes (0.89), NEU (0.88), and NLR (0.88) were higher than CRP (0.64) or Ferritin (0.81).We recommend using FTR, WBC, and NLR changes as simple, useful, and inexpensive indicators in early detection of COVID-19 patients.

Despite substantial efforts, no effective treatment has been discovered for severe acute respiratory syndrome-coronavirus 2 (SARS-CoV-2) infection. Therefore, vaccination to reach herd immunity is the ultimate solution to control the coronavirus disease 2019 (COVID-19) pandemic. This study aimed to evaluate the potency, toxicity, and protection of candidate PastoCoAd vaccines as novel mix and match of recombinant adenovirus type 5 (rAd5) containing the full-length spike protein (rAd5-S), rAd5 containing the receptor-binding domain of S protein and nucleoprotein (rAd5 RBD-N), and SOBERANA dimeric RBD protein of SARS-CoV-2. Three vaccine candidates were developed against SARS-CoV-2 using adenoviral vectors, including the prime-boost (rAd5-S/rAd5 RBD-N), heterologous prime-boost (rAd5-S/ SOBERANA vaccine), and prime only (mixture of rAd5-S and rAd5 RBD-N). The rAd5-S and rAd5 RBD-N were produced with a Cytomegalovirus promoter and the human tissue plasminogen activator (tPA) leader sequence. The immunogenicity of vaccine candidates was also evaluated in mouse, rabbit, and hamster models and protection was evaluated in a hamster model. Following the injection of vaccine candidates, no significant toxicity was observed in the tissues of animal models. The immunogenicity studies of mice, rabbits, and hamsters showed that responses of total IgG antibodies were significantly higher with the prime-only and heterologous prime-boost vaccines as compared to the other groups (P 0.009). Virus neutralizing antibodies were detected, and the level of cytokines related to humoral and cellular immunity increased significantly in all vaccinated models. A high cellular immunity response was found in the vaccinated groups compared to the controls. On the other hand, the vaccine challenge test showed that the virus titers significantly decreased in the pharynx and lung tissues of vaccinated hamsters compared to the control group. These successful findings suggest the safety and protection produced by the heterologous prime-boost vaccine (adenovector/ SOBERANA RBD), as well as a single dose of adenovector vaccine in animal models.

In the present work, bioactive nanoclay-TiO2 (NC-T) bio-nanocomposite scaffolds containing different TiO2 weight fractions are fabricated spacer for bone tissue engineering applications via the space holder technique using NaCl particles as the. The microstructure, surface morphology (porosity) and bioactivity potential of the manufactured bio-nanocomposite scaffolds are examined using scanning electron microscopy (SEM), X-ray diffraction (XRD), X-ray fluorescence (XRF), energy dispersive spectroscopy (EDS), and inductively-coupled plasma optical emission spectroscopy (ICP-OES) techniques. The scaffold with optimized mechanical properties is predicted as NC-15wt%T with proper interconnected porosity and micro/macro pore size within the range of 1–2 (μm) and 3–5 (μm), respectively. Also, its mechanical properties including compressive strength, elastic modulus and crystallite size are extracted equal to 5.74 MPa, 438 MPa and 70–120 nm, respectively. The feasibility of the fabricated scaffolds for bioactive bone tissue engineering application (apatite deposition) is also evaluated using simulated body fluid (SBF) and physiological saline (PS) solutions. At the end, the nonlinear bending and vibration characteristics of an axially loaded beam-type bone implant made of the NC-T/NaCl bio-nanocomposite scaffolds are predicted analytically. In general view, the obtained results indicate that the NC-15wt%T/NaCl bio-nanocomposite scaffold may have excellent advantages for future research in bone regenerative applications.

Nowadays, Pichia pastoris is a well-known yeast for the production of recombinant proteins. The yield of protein production tightly depends on the copy number of the gene of interest into the host chromosome. Real-time PCR has been used as a high throughput method for molecular detection of gene copy number. In light of determining an absolute gene copy number, the reliability of the qPCR quantification standard is a major issue and it can be a potential source of errors in the final results. Since the literature on this issue is inconclusive, we set out to find a reliable quantification method that allows comparing results in different laboratories. We generated standard curves for two genomic loci (5′UTR AOX1 and ARG4) and for plasmid DNA carrying hGM-CSF coding sequence. These data was used to calculate the integrated hGM-CSFcDNA copy number in a recombinant P. pastoris clone. In our expriments the 5′UTR AOX1 gene showed a more accurate quantification standard, based on more efficient amplification and better reproducibility. The results obtained in this study showed that the differences in terms of structure and length between circular plasmid and linear gDNA could be the source of significant differences in the pattern of DNA amplification.

In the current study, bio-nanocomposites scaffolds including natural hydroxyapatite (n-HA) composed with different weight fractions of copper oxide nanoparticles (CuO-NPs) are fabricated using the space holder technique. After that, the manufactured samples are coated with gelatin polymer loaded with ibuprofen drug. Via experimental methods, the mechanical properties (fracture toughness and compressive strength) of n-HA-CuO bio-nanocomposite scaffolds are achieved corresponding to various weight fractions of the CuO-NPs. Also, the electrical conductivity and cell viability of the fabricated scaffolds are evaluated using the scan electron microscope (SEM) and X-ray diffraction (XRD) technique. Thereafter, based upon the extracted mechanical properties, nonlinear mechanical behaviors of beam-type implants made of the prepared n-HA-CuO bio-nanocomposites are predicted analytically. The cell viability and electrical conductivity evaluation demonstrate that on the free surface of all bio-nanocomposite scaffolds, there is a thin layer of apatite carbonate; however, the thickness of this layer in the sample containing 5wt% CuO-NPs is lower than other ones. It is seen that the adherence of ibuprofen's penetration into the gelatin polymer is weak which leads to two explosive release stages. For the lower weight fraction of CuO-NPs, the release of ibuprofen becomes significant.

Background: Expansion and differentiation of stem cells relies on the soluble materials as well as the physical conditions of their microenvironment. Several methods have been studied in attempt to enhance the growth and differentiation rates of different adult stem cells extracted from different sources. Objectives: The purpose was to improve the three-dimensional (3D) culture condition of the semi-permeable polymeric beads for encapsulation of the human adipose-derived mesenchymal stem cells (hADSCs) by modifying the ratio of the alginate-gelatin composition. Materials and Methods: Following isolation and characterization of hADSCs by flow cytometry and their functional differentiation, encapsulation in the alginate and alginate/gelatin compositions were performed. Moreover, the stability, swelling, size frequency, growth kinetics, and cytotoxicity of the beads were measured to meet proper condition in the designed experimental and control culture conditions. Finally, the growth rates of the cells in different experimental groups and control were measured and analyzed statistically. Results: Viability decreased in 2 and 3 percent alginate once compared to 1% alginate in beads (p£0.05). Moreover swelling of the beads in the alginate/gelatin compositions (50:50 and 70:30) were higher than the pure alginate beads (p£ 0.05). Finally, the cell growth rate in alginate/gelatin (50:50) beads was significantly higher than alginate and alginate/gelatin (70:30) beads (p£0.05). Conclusions: These findings suggested for the first time that the composite of alginate/gelatin beads with the ratio of 50:50 might provide a suitable culture condition for the encapsulation and in vitro expansion of the hADSCs.

Background: A study conducted on wound treatment by antibacterial wound dressings can reduce the need for using antibiotics to a minimum amount. These wound dressings can create a moist environment at the wound surface to speed the healing process up. In recent years, researchers have paid much attention to polymeric wound dressings. Chitosan can help heal the wounds because of its similar structure to glycosaminoglycans in the skin. In this regard, the aim of the present study was to fabricate and characterize a novel biolayer wound dressing based on the carboxymethyl chitosan polymer with ceramic nanoparticles as a reinforcement and antibacterial agent using the freeze-drying method. Methods: In this study, to make a flexible wound dressing from a biocompatible and biodegradable polymer, N-O-carboxymethyl chitosan, diopside was added to improve the mechanical and hydrophobic properties of the soft tissue and cell proliferation was fabricated. After making the samples, a variety of chemical and biological tests and analyses were performed on the samples, including scanning electron microscope and Fourier-transform infrared spectroscopy. Results: The results showed that the use of this wound dress significantly reduced the risk of infection at the wound site. Conclusions: An antibacterial product with the proper mechanical behavior as a soft tissue was produced and evaluated in this study. The chemical and biological investigation represented that the sample with 5 wt% magnetite nanoparticles has excellent characteristics and can be introduced as a wound dressing application.

Post-surgical infection is one of the essential problems in bone scaffolds that is usually treated with antibiotics. This issue may be related to the poor blood supply for bone tissue due to high concentrations of drug. In the current study, the effect of zinc oxide (ZnO) nanoparticles on the antibacterial behavior of the nanocrystalline hydroxyapatite (n-HA) scaffolds coated by gelatin-ibuprofen (GN-IBO) is evaluated. To this end, the bio-nanocomposite scaffolds are fabricated via the space holder technique and then characterized with the aid of X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM). The compressive strength, fracture toughness, porosity, elastic modulus as the mechanical properties, and the apatite formation, biodegradation, drug release and wettability beside the roughness as the biological properties are predicted. The obtained experimental results indicate that the bio-nanocomposite scaffolds containing 10 wt% ZnO has suitable mechanical and biological properties. After that, an analytical model is developed to predict the nonlinear instability and vibration responses of an axially loaded sandwich plate-type implants made of the fabricated n-HA-ZnO bio-nanocomposites coated by GN-IBO thin film corresponding to various weight fractions of ZnO nanoparticles. It is found that ZnO peaks in the positions of 2θ are equal to 31.6 ° , 33.6 ° , 34 ° , 46.4 ° , and 62 ° , which represent the crystalline characteristics. Also, it is revealed that through addition of ZnO nanoparticles, the hardness and elastic modulus as well as the bone formation and biodegradation rate of the bio-nanocomposite scaffold enhance, while its drug release in the phosphate buffer solution detected with UV spectrum reduces. It is found that by increasing the ZnO weight fraction, the critical axial buckling load of the sandwich bio-nanocomposite implant enhances, and it buckles at lower axial shortening. However, it is seen that for higher value of wt% ZnO, its influence on the critical buckling load decreases.