Synthesis, characterization, and application of graphene oxide/layered double hydroxide /poly acrylic acid nanocomposite (LDH-rGO-PAA NC) for tetracycline removal: A comprehensive chemometric study.

Tetracycline (TC), as the second produced and used antibiotic worldwide, is difficult to be entirely metabolized not only in the body, but also in the treatment processes of water and/or wastewater. Therefore, special attention needs to be paid on defining or developing new options for removing such contaminant. Herein, a reduced graphene oxide (GO) was integrated with Ni-Al layered double hydroxide (LDH) as well poly acrylic acid (LDH-rGO-PAA) and examined to reduce TC -as a model antibiotic-in water media under different operational parameters of TC initial concentration, pH, NC dose, and time. The governed behaviour in the adsorption process was investigated using three model methods of response surface methodology (RSM), artificial neural networks (ANN), and general regression neural network (GRNN) after confirming the physico-chemical properties of LDH-rGO-PAA nanocomposite (NC) using different techniques. The LDH-rGO-PAA NC displayed a good performance as either removal efficiency (R = 94.87 ± 0.25%) or adsorption capacity (qe = 887.5 mg/g) with the respective values of 110 mg/L, 6.3, 20 mg, and 18.50 min for the mentioned factors (TC initial concentration, pH, NC dose, and time, respectively), which was higher than that of reported for the similar adsorbents until now.

CNT and rGO reinforced PMMA based bone cement for fixation of load bearing implants: Mechanical property and biological response.

Polymethyl methacrylate (PMMA) bone cements (BCs) have some drawbacks, including limited bioactivity and bone formation, as well as inferior mechanical properties, which may result in failure of the BC. To deal with the mentioned issues, novel bioactive polymethyl methacrylate-hardystonite (PMMA-HT) bone cement (BC) reinforced with 0.25 and 0.5 wt% of carbon nanotube (CNT) and reduced graphene oxide (rGO) was synthesized. In this context, the obtained bone cements were evaluated in terms of their mechanical and biological characteristics. The rGO reinforced bone cement exhibited better mechanical properties to the extent that the addition of 0.5 wt% of rGO where its compressive and tensile strength of bioactive PMMA-HT/rGO cement escalated from 92.07 ± 0.72 MPa, and 40.02 ± 0.71 MPa to 187.48 ± 5.79 MPa and 64.92 ± 0.75 MPa, respectively. Besides, the mechanisms of toughening, apatite formation, and cell interaction in CNT and rGO encapsulated PMMA have been studied. Results showed that the existence of CNT and rGO in BCs led to increase of MG63 osteoblast viability, and proliferation. However, rGO reinforced bone cement was more successful in supporting MG63 cell attachment compared to the CNT counterpart due to its wrinkled surface, which made a suitable substrate for cell adhesion. Based on the results, PMMA-HT/rGO can be a proper bone cement for the fixation of load-bearing implants.

Pregnancy and Calving Rates of Cloned Dromedary Camels Produced by Conventional and Handmade Cloning Techniques and In Vitro and In Vivo Matured Oocytes.

Despite practical implication of cloning in camelids, its broad application has been hampered by technical and biological problems. Method of somatic cell nuclear transfer (SCNT) and oocyte competence are the principal technical and biological factors, respectively, that determine the cloning efficiency. This study, therefore, investigated differential contributions of two SCNT methods [modified handmade cloning (mHMC) vs. conventional (cNT)] and two recipient oocyte sources [abattoir-derived (Vitro) vs. FSH-stimulated (Vivo)] on the efficiency of dromedary camel cloning. The mHMC method supported similar rates of fusion, cleavage, and total blastocyst development, compared to conventional NT (cNT) (94, 89.1, and 68.5% vs. 78.9, 92, and 73.5%, respectively) when Vivo oocytes are used. However, using Vitro oocytes, mHMC supported significantly higher rates for these criteria, except for the cleavage, compared to cNT (95.5, 76.2, 25.2% vs. 75.3, 76.7, and 13.9%, respectively). A total of seven clones were born from mHMC/Vitro (four calves), mHMC/Vivo (one calf), cNT/Vitro (one calf), and mHMC/Vivo&Vivo (one calf)-derived embryos with overall efficiencies of 31.9, 26.6, 20, and 30% for initial pregnancy, 10.6, 6.6, 7.5, and 5% for development to term, and 8.5, 6.6, 2.5, 5% for development to weaving, respectively. To conclude, the quality of recipient oocyte greatly impacts cloning efficiency in vitro with no apparent carrying over effect on cloning efficiency in vivo, but the efficiency of SCNT method may compensate for the initial poor oocyte competence during in vitro and in vivo development of cloned embryos. The introduced mHMC could be a superior alternative to conventional method for simple, fast, and efficient production of cloned offspring in camelids.

Investigation of the impact of magnesium versus titanium implants on protein composition in osteoblast by label free quantification.

Metallic implant biomaterials predominate in orthopaedic surgery. Compared to titanium-based permanent implants, magnesium-based ones offer new possibilities as they possess mechanical properties closer to the ones of bones and they are biodegradable. Furthermore, magnesium is more and more considered to be "bioactive" i.e., able to elicit a specific tissue response or to strengthen the intimate contact between the implant and the osseous tissue. Indeed, several studies demonstrated the overall beneficial effect of magnesium-based materials on bone tissue (in vivo and in vitro). Here, the direct effects of titanium and magnesium on osteoblasts were measured on proteomes levels in order to highlight metal-specific and relevant proteins. Out of 2100 identified proteins, only 10 and 81 differentially regulated proteins, compare to the control, were isolated for titanium and magnesium samples, respectively. Selected ones according to their relationship to bone tissue were further discussed. Most of them were involved in extracellular matrix maturation and remodelling (two having a negative effect on mineralisation). A fine-tuned balanced between osteoblast maturation, differentiation and viability was observed.

Morphological and Molecular Analysis of Osteoblasts Differentiated from Mesenchymal Stem Cells in Polycaprolactone/Magnesium Oxide/Graphene Oxide Scaffold.

BACKGROUND: The loss or dysfunction of bone tissue that observed after bone tumor resections and severe nonunion fractures afflicts 200 million people worldwide. Bone tissue engineering is a promising approach to repair osteoporotic fractures. OBJECTIVE: In this paper, polycaprolactone (PCL)/magnesium oxide (MgO)/graphene oxide (GO) nanofibrous scaffold was fabricated by electrospining method, and its biocompatibility and osteogenic differentiation of adipose-derived mesenchymal stem cells (MSCs) on this scaffold were evaluated and compared with pure PCL nanofibrous scaffold. METHODS: SEM analysis, DAPI staining and MTT assay were used to evaluation biocompatibility of PCL/MgO/GO composite scaffold. In addition by ALP assay and proteomic approach, osteostimulatory effect of electrospun composite scaffold was investigated and the expression level of osteogenic markers including Runt-related transcription factor cbfa1/runx2 (runx2), collagen type I (Col1a1) and osteopontin (OPN) in MSCs seeded on PCL/MgO/GO composite scaffold was determined and compared with pure PCL scaffold. Then, RT-PCR technique was used to validate the level expression of these genes. RESULTS: The obtained results showed that adhesion, viability and ALP activity of MSCs on PCL/MgO/GO scaffold considerably enhanced compared with pure PCL. As well as proteomic and real-time analysis illustrated the expression of osteogenic markers including runx2, Col1a1 and OPN increased (>2-fold) in cells seeded on PCL/MgO/GO composite scaffold. CONCLUSION: It was concluded that MgO and GO nanoparticles could improve the biocompatibility of PCL scaffold and enhance the osteogenic differentiation of MSCs.

Optimization of radioactive sources to achieve the highest precision in three-phase flow meters using Jaya algorithm.

Gamma ray source has very important role in precision of multi-phase flow metering. In this study, different combination of gamma ray sources ((133Ba-137Cs), (133Ba-60Co), (241Am-137Cs), (241Am-60Co), (133Ba-241Am) and (60Co-137Cs)) were investigated in order to optimize the three-phase flow meter. Three phases were water, oil and gas and the regime was considered annular. The required data was numerically generated using MCNP-X code which is a Monte-Carlo code. Indeed, the present study devotes to forecast the volume fractions in the annular three-phase flow, based on a multi energy metering system including various radiation sources and also one NaI detector, using a hybrid model of artificial neural network and Jaya Optimization algorithm. Since the summation of volume fractions is constant, a constraint modeling problem exists, meaning that the hybrid model must forecast only two volume fractions. Six hybrid models associated with the number of used radiation sources are designed. The models are employed to forecast the gas and water volume fractions. The next step is to train the hybrid models based on numerically obtained data. The results show that, the best forecast results are obtained for the gas and water volume fractions of the system including the (241Am-137Cs) as the radiation source.

In vitro Evaluation of the Relationship between Gray Scales in Digital Intraoral Radiographs and Hounsfield Units in CT Scans.

BACKGROUND: Jaw bone quality plays an essential role in treatment planning and prognosis of dental implants. Regarding several available methods for bone density measurements, they are not routinely used before implant surgery due to hard accessibility. OBJECTIVE: An in vitro investigation of correlation between average gray scale in direct digital radiographs and Hounsfield units in CT-Scan provides a feasible method for evaluating alveolar bone quality prior to implant surgery. METHODS: 26 sheep's mandibles in which a square shape ROI marked by gutta percha, were prepared. Three direct digital radiographs (CCD sensor) from every specimen were taken using 80, 100 and 200 milli-seconds. Then, the average gray levels for ROIs were calculated using a costume-made software. Next, the specimens were scanned using a 16-slice spiral CT and the Hounsfield Unit of each ROI was calculated. Pearson analysis measured the correlation between Hounsfield units and average gray levels. RESULTS: There was a positive correlation between Hounsfield unit and average gray level in the radiographs and the correlation was better in higher exposure times. CONCLUSION: It is possible to estimate Hounsfield unit and bone density in the jaw bones using average gray scale in a digital radiograph. This approach is easy, simple and available and also results in lower patient exposure comparing other bone densitometric analysis methods.

Homogenization of tissues via picosecond-infrared laser (PIRL) ablation: Giving a closer view on the in-vivo composition of protein species as compared to mechanical homogenization.

Posttranslational modifications and proteolytic processing regulate almost all physiological processes. Dysregulation can potentially result in pathologic protein species causing diseases. Thus, tissue species proteomes of diseased individuals provide diagnostic information. Since the composition of tissue proteomes can rapidly change during tissue homogenization by the action of enzymes released from their compartments, disease specific protein species patterns can vanish. Recently, we described a novel, ultrafast and soft method for cold vaporization of tissue via desorption by impulsive vibrational excitation (DIVE) using a picosecond-infrared-laser (PIRL). Given that DIVE extraction may provide improved access to the original composition of protein species in tissues, we compared the proteome composition of tissue protein homogenates after DIVE homogenization with conventional homogenizations. A higher number of intact protein species was observed in DIVE homogenates. Due to the ultrafast transfer of proteins from tissues via gas phase into frozen condensates of the aerosols, intact protein species were exposed to a lesser extent to enzymatic degradation reactions compared with conventional protein extraction. In addition, total yield of the number of proteins is higher in DIVE homogenates, because they are very homogenous and contain almost no insoluble particles, allowing direct analysis with subsequent analytical methods without the necessity of centrifugation. BIOLOGICAL SIGNIFICANCE: Enzymatic protein modifications during tissue homogenization are responsible for changes of the in-vivo protein species composition. Cold vaporization of tissues by PIRL-DIVE is comparable with taking a snapshot at the time of the laser irradiation of the dynamic changes that occur continuously under in-vivo conditions. At that time point all biomolecules are transferred into an aerosol, which is immediately frozen.

Potential chemoprotective effects of selenium on diazinon-induced DNA damage in rat peripheral blood lymphocyte.

The purpose of this study was to investigate the protective effects of selenium (Se) against genotoxicity induced by diazinon (DZN) in rat peripheral blood lymphocytes by micronucleus (MN) test. Animals were concurrently administered intraperitoneally with DZN in proper solvent (20 mg/kg body weight (b.w.)) and Se at three different doses (0.5, 1, and 2 mg/kg b.w.) for 30 consecutive days. The positive control group received DZN at the same dose without Se. After 24 h of last injection, 0.5 ml blood of each rat was received and cultured in culture medium for 44 h. The lymphocyte cultures were mitogenically stimulated with cytochalasin B to allow the evaluation of number of MNs in cytokinesis-blocked binucleated cells. Incubation of lymphocytes with DZN induced additional genotoxicity and is shown by increase in MNs frequency in human lymphocytes. Se at low dose of 0.5 mg/kg had a maximum effect and significantly reduced the MNs frequency in cultured lymphocytes (p < 0.0001) that reduced the frequency of MN from 12.78 ± 0.24% for DZN group to 4.40 ± 0.36. The present study revealed that Se particularly at low doses has a potent antigenotoxic effect against DZN -induced toxicity in rats, which may be due to the scavenging of free radicals and increased antioxidant status.

Chitinase gene transformation through Agrobacteriumand its explanation in soybean in order to induce resistance to root rot caused by Rhizoctonia solani.

Chitinase gene (chi) of bean which has been cloned in recombinant binary plasmid vector, pBI121 with 35s promoter of Cauliflower mosaic virus (CaMV), were used for transformation of soybean using strain LBA4404 of Agrobacterium. The plasmid contained nptII gene that is a resistant gene to kanomycin as selector marker and Gus gene as reporter. Cotyledon explants of Williams and Clark cultivars were inoculated by Agrobacterium suspension with pBI121 and were cultured in regeneration medium. After complete regeneration of explants to seedling in B5 medium amended with kanomycin, polymerase chain reaction analysis were conducted to ensure conjugation of nptII, Gus, CHN genes in transformants seedling of soybean. Results showed that some lines of soybean contained Gus and CHN genes. More ever, chitinase activity in leaf extract of transformed soybean lines was significantly more than untransformed soybean, exception one sample. Bioassay of chitinase activity of transgenic lines on in vitro condition prevented mycelial growth of Rhizoctonia solani in comparison with untransformed control leaf extract.