Higher Cell Adhesion Research Articles

Characteristics and biological control functions of Bacillus sp. PM8313 as a host-associated probiotic in red sea bream (Pagrus major) aquaculture.

Host-associated probiotics (HAPs) are bacteria originally isolated from rearing water or the host's gastrointestinal tract in order to enhance the host's growth and health. This study investigated the HAP potential of Bacillus sp. PM8313, isolated from wild red sea bream (Pagrus major), through characterization and feeding trials. Results based on invitro tests showed that PM8313 is safe, confirming its hemolytic, cytotoxic, and antibiotic resistance. In addition, PM8313 showed advantages as a probiotic with high viability in the gastrointestinal model and a high cell adhesion rate. Whole-genome sequencing demonstrated that PM8313 has a 4,615,871 bp single circular chromosome and a guanine-cytosine content of 45.25%. It also showed the absence of genes encoding virulence factors, such as cytotoxin, enterotoxin, hemolysin, sphingomyelinase, and phospholipase. In the feeding trial, a supplemental diet of 1×108CFU/g PM8313 positively altered the weight gain, digestive enzyme activity, and intestinal microbiota composition of red sea bream. Analysis of nonspecific immune parameters and immune-related gene expression, and a challenge test showed that PM8313 supplementation increases immunity and pathogenic bacteria resistance. Our findings suggest that PM8313 should be considered for application as a novel HAP to red sea bream aquaculture.

Recombinant humanized collagen remodels endometrial immune microenvironment of chronic endometritis through macrophage immunomodulation.

Recently, evidence has suggested that chronic endometritis (CE) is a crucial factor associated with infertility and failure of assisted reproductive techniques, prompting concern in the reproductive field. Studies have shown that persistent infiltered immune cells stimulation result in the disturbance of endometrial immune microenvironment could lead to the infertility of CE patients finally. Conventional treatments are limited because they lack immune regulation, so it is urgent to develop a novel approach to treat CE and promote embryo implantation in patients with CE. Herein, we prepared recombinant humanized type III collagen (rhCol III) with high cell adhesion activity to regulate macrophages and repair the endometrium. In this study, M1 macrophages and M1 macrophages cultured medium and lipopolysaccharide (LPS) co-stimulated inflammatory endometrium stromal cells (ESCs) were established in vitro to mimic CE condition. rhCol III promoted M1 macrophages toward M2 phenotype, improved cell migration, viability and collagen components of inflammatory ESCs. Also, the inflammatory response of inflammatory ESCs was downregulated after rhCol III treatment. Subsequently, LPS was used for CE rat model and a 28-day observation was performed; inflammatory cells' infiltration, endometrium repair, extracellular matrix (ECM) remodeling and pregnancy outcomes were promoted after rhCol III endometrial infusion. In conclusion, rhCol III promoted (i) macrophage polarization toward M2 macrophages, (ii) pro-inflammatory cytokine production and anti-inflammatory cytokine reduction, (iii) ECM remodeling and (iv) fertility restoration. Meanwhile, rhCol III enhanced cell biological functions by interacting with discoidin domain receptors, regulated cell metabolism and reduced the inflammatory response through the inhibition of the NF-κB/YAP signaling pathway. Overall, the results illustrated the potential therapeutic prospects of rhCol III for CE treatment.

Fabrication and characterization of electrospun GelMA/PCL/CS nanofiber composites for wound dressing applications

In the present study, the effect of different ratios of GelMA concentration has been exhibited for wound dressing implementation by the electrospinning method using a new polymer combination of Gelatin methacrylate (GelMA)/Polycaprolactone (PCL)/Chitosan (CS). The nanofiber composites were fabricated due to their biocompatible, biodegradable, improved mechanical strength, low degradation rate, and hydrophilic nature to develop cell-mimicking, cell adhesion, proliferation, and differentiation. Different concentrations of GelMA were added to the PCL/CS solution as 5, 10, and 20 wt%, respectively, in the formic acid/acetic acid (7:3) solution. A photoinitiator was added to the solution for photo-crosslinking of GelMA. The influence of different solution concentrations (5, 10, and 20 wt%) on the structure’s nanofiber production and fiber morphology was examined. SEM micrographs revealed that varied GelMA concentrations resulted in suitable and stable nanofiber composites. The average diameter of nanofiber composites grows as the GelMA concentration rises. FTIR, DSC, tensile test, degradation, and swelling test were evaluated. The results demonstrated that high mechanical strength, hydrophilic properties, and a slow degradation rate were observed with the presence and increment of GelMA concentration within the nanofiber composites. The antibacterial potential of GelMA/PCL/CS nanofiber composites was evaluated against P. aeruginosa and S. aureus using a disc diffusion assay. In vitro cell culture research was conducted by seeding NIH 3T3 fibroblast cells on nanofiber composites, proving these cells’ high cell proliferation rate, viability, and adhesion. 10 wt% GelMA-based nanofiber composites were found to have great potential for wound dressing applications.

In Vitro Study on Collagen Application in Wound Healing: A Systematic Review

Collagen is key component of extracellular matrix for human and animals. It can be extracted and applied for various field especially in tissue engineering as main component for wound healing. Collagen especially type I collagen is used in skin regeneration process due to its high compatibility with donor site and low antigenicity besides of having suitable properties for wound healing like high cell proliferation and adhesion. However, the usage of collagen alone would not give maximum wound healing since collagen degrades faster, has poor structure for a scaffold and attracts bacteria due to high moisture content. Therefore, to produce a good collagen scaffold, it must be incorporated with functional biomaterials to enhance the characteristic of the collagen and fabricated for a better scaffold structure. The objective of this systematic review is to summarize the relevant literature for in vitro study on collagen application in wound healing by focusing on the source of collagen, biomaterials and fabrication methods used in making collagen scaffold. Three databases were searched; PubMed, Scopus and Science Direct. Keywords used were: collagen, recombinant collagen, collagen scaffold, application and wound healing. A total of 1105 were articles screened but only 50 articles were suitable and were further reviewed. Collagen in wound healing study has versatility in terms of the source of collagen used, the biomaterials combined with the collagen to make an enhanced scaffold, and the fabrication methods to create a desirable structure of collagen scaffold.

Viability and Adhesion of Periodontal Ligament Fibroblasts on a Hydroxyapatite Scaffold Combined with Collagen, Polylactic Acid-Polyglycolic Acid Copolymer and Platelet-Rich Fibrin: A Preclinical Pilot Study.

Background: Conventional periodontal therapy relies on bone regeneration strategies utilizing scaffolds made of diverse materials, among which collagen, to promote cell adhesion and growth. Objective: To evaluate periodontal ligament fibroblast (HPdLF) cell adhesion and viability for periodontal regeneration purposes on hydroxyapatite scaffolds containing collagen (HAp-egg shell) combined with polylactic acid–polyglycolic acid copolymer (PLGA) and Platelet-Rich Fibrin (PRF). Methods: Four variations of the HAp-egg shell were used to seed HPdLF for 24 h and evaluate cell viability through a live/dead assay: (1) (HAp-egg shell/PLGA), (2) (HAp-egg shell/PLGA + collagen), (3) (HAp-egg shell/PLGA + PRF) and (4) (HAp-egg shell/PLGA + PRF + collagen). Cell adhesion and viability were determined using confocal microscopy and quantified using central tendency and dispersion measurements; significant differences were determined using ANOVA (p < 0.05). Results: Group 1 presented low cell viability and adhesion (3.70–10.17%); groups 2 and 3 presented high cell viability and low cell adhesion (group 2, 59.2–11.1%, group 3, 58–4.6%); group 4 presented the highest cell viability (82.8%) and moderate cell adhesion (45%) (p = 0.474). Conclusions: The effect of collagen on the HAp-egg shell/PLGA scaffold combined with PRF favored HPdLF cell adhesion and viability and could clinically have a positive effect on bone defect resolution and the regeneration of periodontal ligament tissue.

The prognosis of endometrial cancers stratified with conventional risk factors and modified molecular classification.

This study aimed to validate the Proactive Molecular Risk Classifier for Endometrial Cancer, a modified version of The Cancer Genome Atlas, using data from 184 patients with endometrial cancer (median age: 57.5 years; median follow‐up period: 109 months) who had undergone radical surgery (including systemic lymphadenectomy) and subsequent adjuvant chemotherapy (patients with intermediate or high recurrence risk) from 2003 to 2015. Tissue microarrays were prepared from surgical specimens and classified using the conventional clinical risk classifier. Immunohistochemistry was used to detect mismatch repair proteins, L1 cell adhesion molecule, and p53. Direct sequencing was used to identify hotspot mutations in the polymerase‐epsilon gene. Forty‐five patients were identified as having high L1 cell adhesion molecule expression, 41 as low risk, 34 as mismatch repair‐deficient, 13 as polymerase‐epsilon gene‐mutated, five as having abnormal p53, and 46 as other. Patients were stratified into significantly different prognostic groups (p < 0.0001): favorable (low risk and polymerase‐epsilon gene‐mutated), intermediate (mismatch repair‐deficient and other), and unfavorable (high L1 cell adhesion molecule expression and abnormal p53) with 5‐year disease‐specific survival rates of 100%, 93.8%, and 75.1%, respectively (Kaplan–Meier method). The combination of conventional recurrent risk classification, sequencing for polymerase‐epsilon gene mutations and immunohistochemistry for L1 cell adhesion molecule, p53, and mismatch repair proteins can be used to determine the prognoses of patients with endometrial cancer.

Screening for probiotic attributes of lactic acid bacteria isolated from human milk and evaluation of their anti-diabetic potentials

ABSTRACT Lactic acid bacteria (LAB) have gained much attention recently due to their probiotic attributes with anti-ACE and anti-glycation potentials targeting management of diabetes. This study was designed to isolate LAB from human milk and to evaluate their potential for inhibitory activities on ACE and AGEs formation using in vitro assay models. Among 12 LAB isolates, many strains exhibited strong probiotic attributes including tolerance to low pH, high salt, gastric, and intestinal juices with higher cell adhesion. Further, cell-free extracts of LAB tested for in vitro anti-ACE and anti-AGEs activities evidenced Lacticaseibacillus casei MKU1, Lacticaseibacillus paracasei MKU2, Lactiplantibacillus pentosus MKU3, L. paracasei MKU7, L. delbrueckii GERU3 and Lactobacillus delbrueckii MKU10 as strong ACE and AGEs inhibitors. Subsequently, Principal Component Analysis showed a positive correlation with anti-ACE (p ≤ .01) and anti-glycation (p ≤ .05) activity of LAB. Overall, this study suggests that six Lactobacillus isolates of human milk with superior probiotic attributes looks promising as potential probiotic strains.

Encapsulation of Lactic Acid Bacteria by Lyophilisation with Its Effects on Viability and Adhesion Properties.

Lactobacillus (LAB) genera are considered important functional food but are found to have a short shelf life. In this study, two LAB, Lactobacillus plantarum (Lp) and Lactobacillus rhamnosus (Lr), were isolated from sheep's milk, and whole-genome sequencing was carried out by using 16s rRNA Illumina Nextseq, the Netherlands. The LAB were encapsulated by the lyophilisation technique using different lyoprotective pharmaceutical excipients. This process was carried out using a freeze dryer (U-TECH, Star Scientific Instruments, India). Shelf-life determination was carried out by a 12-month study using the viability survival factor (Vsf). The in vitro cell adhesion technique was carried out by using the red snapper fish along with autoaggregation and cell surface hydrophobicity as vital probiotic properties. It was observed that Lp has a significantly higher (P < 0.001) Vsf of 7.2, while Lr has a Vsf of 7 (P < 0.05) when both are encapsulated with 10% maltodextrin + 5% sucrose kept at 4°C for 12 months. The result demonstrated that Lp had significantly high (P < 0.05) cell adhesion, 96% ± 1.2 autoaggregation, and 6% cell surface hydrophobicity as compared to Lr. Moreover, this study demonstrated that lyophilised LAB with lyoprotective excipients enhances shelf life without any changes in probiotic properties when kept at 4°C exhibiting all its probiotic properties.

Bio-Physical Properties of Acetylated Chitosan/Poly(ɛ-Caprolactone) Composites for Three-Dimensional Printing Material Applications.

For three-dimensional (3D) printing material applications in tissue engineering, acetylated chitosan (AC)/poly(ɛ-caprolactone) (PCL) composites were prepared by the melt mixing method using the acetylation of chitosan with PCL. The physiochemical properties of the AC/PCL composites were examined by measuring the water contact angles, dispersity of AC on the cross-section using scanning electron microscopy, and temperature stability. In addition, mechanical properties such as tensile strength and bending stress recovery were measured to determine the elasticity of the composite films. The fibroblast cell line NIH-3T3 was used to test the relative cell affinities based on the AC content and cell viability on AC/PCL at various temperatures. There was no difference between the melting points and tensile strengths of the AC/PCL composites and pure PCL. Overall, the AC/PCL composites showed high initial cell adhesion after 4 h of cell culture and increased cell proliferation compared to those of PCL composites used as a control. Based on these tests, an AC of 10.7 wt% was determined to be the optimal composition for the AC/PCL composite. Thus, these composites can be used in various 3D printing material applications in tissue engineering.

Characterization of non-solvent- and thermal-induced phase separation applied polycaprolactone/demineralized bone matrix scaffold for bone tissue engineering

ObjectivePolycaprolactone (PCL) is a widely applied biomaterial in bone tissue engineering (BTE) due to its superior mechanical properties and biodegradability. However, the high hydrophobicity and low cell adhesion properties of PCL show limited cell interactions. Herein, we prepared the porous PCL/DBP composites with improved cell adhesion through the addition of demineralized bone powder (DBP). Three-dimensional scaffolds were fabricated by mixing various concentrations of DBP with PCL and applying non-solvent-induced phase separation (NIPS) and thermal-induced phase separation (TIPS) (N-TIPS) and solvent casting and particulate leaching (SCPL) to impart porosity.MethodsA characteristic evaluation was performed through X-ray diffraction (XRD), morphological analysis, physicochemical analysis, bioactivity test, and mechanical test. Upon culture with mouse bone marrow stem cells (mBMSCs), proliferation and osteogenic differentiation of mBMSC were evaluated using quantitative dsDNA analysis and alkaline phosphatase (ALP) activity, respectively.ResultsThe addition of DBP improved the physicochemical and mechanical properties of the scaffold and formed a large amount of hydroxyapatite (HAp). Also, cell proliferation and differentiation were increased by enhancing cell adhesion.ConclusionThe porous PCL/DBP scaffolds could provide a favorable microenvironment for cell adhesion and be a promising biomaterial model for bone tissue engineering.Graphical abstract

PVA-AAm-AG multi-network hydrogel with high mechanical strength and cell adhesion

The self-healing ability of articular cartilage is poor, and hydrogel materials are expected to be used for cartilage replacement due to their high-water content and good biocompatibility. Here, the polyvinyl alcohol-acrylamide-agarose multi-network hydrogel was proposed. The hydrogel has a compressive modulus of 1.19 MPa and a compressive strength limit of 8.87 MPa, as well as a tensile modulus of 0.63 MPa and a tensile strength limit of 1.08 MPa. The mechanical properties of hydrogel meet the requirement for cartilage replacement materials. The in vitro cell experiments indicate that the introduction of agarose improves the cell adhesion of the hydrogel, which is expected to be beneficial in the field of biomedicine.

Injectable recombinant human collagen-derived material with high cell adhesion activity limits adverse remodelling and improves pelvic floor function in pelvic floor dysfunction rats

Female pelvic floor dysfunction (FPFD) is a life-changing condition that severely affects women's physical and mental health. Despite the effectiveness of current treatments for FPFD, there is a high rate of short-term recurrence. Here, we introduced an injectable recombinant human collagen (rhCOL)-derived material with high cell adhesion activity to achieve pelvic floor repair and extracellular matrix (ECM) assembly. In our study, rhCOL promoted human uterosacral ligament fibroblast (HULF) adhesion, migration, and collagen I and III expression and regulated the metabolism of HULFs in vitro. Subsequently, we established a rat model of FPFD. Then, rhCOL, including rhCOLI and rhCOLIII, was perivaginally injected into FPFD rats, resulting in a significant increase in abdominal urine leak point pressure (LPP) and maximum tensile strength compared to the FPFD model group. Better organization of the lamina propria and muscularis in FPFD rats was observed after 14 days of rhCOL treatment. Meanwhile, the expression of collagen I, collagen III, and TIMP1 was upregulated, and MMP2 was downregulated. Furthermore, rhCOL promoted HULF adhesion, migration, and ECM synthesis by upregulating the focal adhesion kinase (FAK)/RhoA/ROCK signalling pathway in vitro and in vivo. These findings suggest that the perivaginal injection of rhCOL is a promising treatment for FPFD with potential for future clinical use.

Crosslinking effect of dialdehyde cholesterol modified starch nanoparticles on collagen hydrogel

Crosslinking is frequently used to improve the inherent poor physicochemical properties of collagen. However, local flocculation and irregular crosslinking of collagen would be unavoidably occurred once contacting with crosslinking agents due to widespread complex interactions. Herein, dialdehyde starch-based nanoparticles were developed to crosslink collagen as a new strategy. Starch was conjugated with cholesterol chloroformate before periodate oxidation to obtain dialdehyde cholesterol modified starch (DACS). DACS self-assembled into nanoparticles (DACSNPs) and crosslinked with collagen to fabricate collagen hydrogels (DACSNPs-Col). DACSNPs-Col hydrogels exhibited faster gelation rate, better uniform porous structure, higher mechanical properties and better degradation stability than dialdehyde starch crosslinked hydrogels. Significantly, DACSNPs-Col hydrogels show homogeneous structure, improved mechanical properties, low cytotoxicity, well blood compatibility, high cell adhesion and proliferation. Overall, the oxidized polysaccharide nanoparticles crosslinked collagen hydrogels have homogeneous and compact microstructure and improved physicochemical properties, which show potential application prospect in the field of tissue engineering scaffold.

Accurate Isolation of Circulating Tumor Cells via a Heterovalent DNA Framework Recognition Element-Functionalized Microfluidic Chip.

Detection of circulating tumor cells (CTCs) has provided a noninvasive and efficient approach for early diagnosis, treatment, and prognosis of cancer. However, efficient capture of CTCs in the clinical environment is very challenging because of the extremely rare and heterogeneous expression of CTCs. Herein, we fabricated a multimarker microfluidic chip for the enrichment of heterogeneous CTCs from peripheral blood samples of breast cancer patients. The multimarker aptamer cocktail DNA nanostructures (TP-multimarker) were modified on a deterministic lateral displacement (DLD)-patterned microfluidic chip to enhance the capture efficiency through the size selection effect of DLD arrays and the synergistic effect of multivalent aptamers. As compared to a monovalent aptamer-modified chip, the multimarker chip exhibits enhanced capture efficiency toward both high and low epithelial cell adhesion molecule expression cell lines, and the DNA nanostructure-functionalized chip enables the accurate capture of different phenotypes of CTCs. In addition, the DNA nanoscaffold makes nucleases more accessible to the aptamers to release cells with molecular integrity and outstanding cell viability.

Enhanced bioactivity and interfacial bonding strength of Ti3Zr2Sn3Mo25Nb alloy through graded porosity and surface bioactivation

• A coating with pores of several microns in diameter is created through micro arc oxidation (MAO) on the surface of the gradient porous Ti 3 Zr 2 Sn 3 Mo 25 Nb alloy with larger pores of hundreds microns fabricated from powder sintering on the solid alloyed core. • The MAO treatment in an electrolyte containing Ca and P enables the secondary microporous coating contained hydroxyapatite (HA), and the bone morphogenetic protein-2 (BMP-2) was further loaded on to the coating (HA+BMP). • Both HA and BMP-2 on the surface and inside pores significantly activate the bioactive of the alloy by promoting the formation of new bone tissue on the surface and stimulating new bone tissue to growth into the gradient porous Ti 3Zr2Sn3Mo25Nb alloy. • The interfacial shear strength of the coatings with HA or HA+BMP is higher than that of the coating without both HA or BMP-2 at all time after implantation, the strength in the HA+BMP coating is highest in the three coatings and is about three times of the strength of the CPT sample in all the testing implantation intervals. The gradient porous Ti3Zr2Sn3Mo25Nb (TLM) alloy rods were fabricated through sintering the alloyed powder to a solid core. The porous sample was then modified by a Micro Arc Oxidation (MAO) treatment in an electrolyte containing calcium and phosphate, a hydrothermal treatment enabled secondary microporous hydroxyapatite (HA) coating, and a further bone morphogenetic protein-2 (BMP-2) loading treatment through immersion and freeze-drying. The treatment led to an orderly secondary microporous coating containing HA nano-particles and evenly distributed BMP-2 in the porous coatings. As a result, osteoblasts could adhere and grow well on the coatings with a high cell adhesion rate and cell functional activity. The in-situ shear testing indicated that the interfacial strength had been enhanced significantly. Improvement of the bond formation and osseointegration with the titanium implant is attributed to increased surface area for the cell to attach, creating voids for the cell to grow in, and activating titanium surface by introducing bioactive ingredients such as HA and BMP-2.

Chitosan-collagen-hydroxyapatite membranes for tissue engineering

Tissue engineering is growing in developing new technologies focused on providing effective solutions to degenerative pathologies that affect different types of connective tissues. The search for biocompatible, bioactive, biodegradable, and multifunctional materials has grown significantly in recent years. Chitosan, calcium phosphates collagen, and their combination as composite materials fulfill the required properties and could result in biostimulation for tissue regeneration. In the present work, the chitosan/collagen/hydroxyapatite membranes were prepared with different concentrations of collagen and hydroxyapatite. Cell adhesion was evaluated by MTS assay for two in vitro models. Additionally, cytotoxicity of the different membranes employing hemolysis of erythrocytes isolated from human blood was carried out. The structure of the membranes was analyzed by X-rays diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and thermal stability properties by thermogravimetric methods (TGA). The highest cell adhesion after 48 h was obtained for chitosan membranes with the highest hydroxyapatite and collagen content. All composite membranes showed good cell adhesion and low cytotoxicity, suggesting that these materials have a significant potential to be used as biomaterials for tissue engineering.Graphical abstract

Conserved FimH mutations in the global Escherichia coli ST131 multi-drug resistant lineage weaken interdomain interactions and alter adhesin function

The binding of the type 1 fimbrial adhesin FimH to mannosylated receptors is allosterically regulated to enhance the fitness of uropathogenic Escherichia coli (UPEC) during urinary tract infection (UTI). Mutations in the two FimH domains (pilin and lectin) located outside the mannose binding pocket have been shown to influence mannose binding affinity, yet the details of the allostery mechanism are not fully elucidated. Here we characterised different FimH conformational states (termed low-affinity tense and high-affinity relaxed conformations) of natural FimH variants using molecular dynamics (MD) simulation techniques and report key structural dynamics differences between them. The clinically dominant FimH30 variant from the pandemic multidrug resistant E. coli ST131 lineage contains an R166H mutation that weakens FimH interdomain interactions and allows enhanced mannose interactions with pre-existing high-affinity relaxed conformations. When expressed in an isogenic ST131 strain background, FimH30 mediated high human cell adhesion and invasion, and enhanced biofilm formation over other variants. Collectively, our computational and experimental findings support a model of FimH protein allostery that is mediated by shifts in the pre-existing conformational equilibrium of FimH, additional to the sequential step-wise process of structural perturbations transmitted from one site to another within the protein. Importantly, it is the first study to shed light into how natural mutations in a clinically dominant FimH variant influence the protein’s conformational landscape optimising its function for ST131 fitness at intestinal and extraintestinal niches.

Biodegradable Hydrogel Scaffolds Based on 2-Hydroxyethyl Methacrylate, Gelatin, Poly(β-amino esters), and Hydroxyapatite.

New composite 3D scaffolds were developed as a combination of synthetic polymer, poly(2-hydroxyethyl methacrylate) (PHEMA), and a natural polymer, gelatin, with a ceramic component, nanohydroxyapatite (ID nHAp) dopped with metal ions. The combination of a synthetic polymer, to be able to tune the structure and the physicochemical and mechanical properties, and a natural polymer, to ensure the specific biological functions of the scaffold, with inorganic filler was applied. The goal was to make a new material with superior properties for applications in the biomedical field which mimics as closely as possible the native bone extracellular matrix (ECM). Biodegradable PHEMA hydrogel was obtained by crosslinking HEMA by poly(β-amino esters) (PBAE). The scaffold’s physicochemical and mechanical properties, in vitro degradation, and biological activity were assessed so to study the effects of the incorporation of nHAp in the (PHEMA/PBAE/gelatin) hydrogel, as well as the effect of the different pore-forming methods. Cryogels had higher elasticity, swelling, porosity, and percent of mass loss during degradation than the samples obtained by porogenation. The composite scaffolds had a higher mechanical strength, 10.14 MPa for the porogenated samples and 5.87 MPa for the cryogels, but a slightly lower degree of swelling, percent of mass loss, and porosity than the hybrid ones. All the scaffolds were nontoxic and had a high cell adhesion rate, which was 15–20% higher in the composite samples. Cell metabolic activity after 2 and 7 days of culture was higher in the composites, although not statistically different. After 28 days, cell metabolic activity was similar in all scaffolds and the TCP control. No effect of integrating nHAp into the scaffolds on osteogenic cell differentiation could be observed. Synergetic effects occurred which influenced the mechanical behavior, structure, physicochemical properties, and interactions with biological species.

Isolation and characterization of Bacillus spp. from aquaculture cage water and its inhibitory effect against selected Vibrio spp.

The aim of this study was to evaluate the probiotic potential of Bacillus strains with antibacterial activity against Vibrio spp. in vitro. 13 Bacillus strains were selected using Bacillus-selective agar. Among the strains elected in the preliminary screening for antagonistic effect, only the strain PJ_11 with better antibacterial ability was selected and used in further experiments. Based on the morphological and biochemical features with phylogenetic analysis of the 16S rRNA sequencing, selected strain was identified as B. pumilus. PJ_11 showed probiotic properties such as able to survive in wide range of temperatures and salinity, tolerance to 0.3% oxgal and pH 2.0, and high cell-adhesion activity. In this study, there was no special feature regarding the inhibitory effect of the isolate against Gram-positive or Gram-negative indicator bacteria. However, the inhibition effect of the culture was found to be greater than that of the supernatant. PJ_11 exhibited strong antibacterial activity against Vibrio vulnificus, Vibrio parahaemolyticus and Vibrio anguillarum that were isolated from fish (Dicentrarchus labrax) with disease symptoms. The inhibition diameter of strain PJ_11 ranged from 17.63 to 26.68mm. In co-culture assay with the strain PJ_11 culture, the growth of V. vulnificus, V. parahaemolyticus and V. anguillarum was inhibited after 120h with an initial level of 1.0 × 108CFU/mL. PJ_11 had antibiotic susceptibility to commonly used antibiotics in aquaculture but only resistant to chloramphenicol. Isolate was non-hemolytic. These findings suggested that the strain PJ_11 is good probiotic candidate and may have potential applications to prevent/control vibriosis in aquaculture.

Fabrication of Mesoporous Silica Nanoparticle-Incorporated Coaxial Nanofiber for Evaluating the In Vitro Osteogenic Potential.

The most important role of tissue engineering is to develop a biomaterial with a property that mimics the extracellular matrix (ECM) by enhancing the lineage-specific proliferation and differentiation with favorable regeneration property to aid in new tissue formation. Thus, to develop an ideal scaffold for bone repair, we have fabricated a composite nanofiber by the coaxial electrospinning technique. The coaxial electrospun nanofiber contains the core layer, consisting of polyvinyl alcohol (PVA) blended with oregano extract and mesoporous silica nanoparticles (PVA-OE-MSNPs), and the shell layer, consisting of poly-ε-caprolactone blended with collagen and hydroxyapatite (PCL-collagen-HAP). We evaluated the physicochemical properties of the nanofibers using X-ray diffraction (XRD), thermogravimetric analysis (TGA), scanning electron microscopy (SEM), and Fourier transform infrared spectroscopy (FTIR). In vitro biocompatibility, cell adhesion, cell viability, and osteogenic potential were evaluated by 3-(4,5-dimethylthiazole-2-yl)-2,5-diphenlytetrazolium bromide (MTT), calcein AM, and alkaline phosphatase (ALP) activity and Alizarin Red staining in NIH 3T3/MG-63 cells. The results showed that the nanoparticle-incorporated coaxial nanofiber was observed with bead-free, continuous, and uniform fiber morphology with a mean diameter in the range of 310 ± 125nm. From the biochemical studies, it is observed that the incorporation of nanofiber with HAP and MSNPs shows good swelling property with ideal porosity, biodegradation, and enhanced biomineralization property. In vitro results showed that the scaffolds with nanoparticles have higher cell adhesion, cell viability, ALP activity, and mineralization potential. Thus, the fabricated nanofiber could be an appropriate implantable biomaterial for bone tissue engineering.