303 research outputs found
Application of Hydrus-2D for simulation of water distribution in different types of soils
Study of water distribution in the soil as a result of water application involves simulation of water movement in
porous media. Water distribution in the soil depends on the hydraulic properties of the soil. In the present study,
water distribution in the root zone depth of the green pepper was simulated at various emitter discharges under
different fertigation strategies for various types of soils. A two-dimensional water and solute transport model
Hydrus-2D was selected for the simulation. Experiments were conducted with the research farm of Bastam
Agricultural Center, Shahrood, Iran to investigate the water distribution pattern under different types of soils.
Investigation of water distribution in soil was done in seven types of soils. For simulation of water movement in
soil Hydrus-2D was calibrated and validated. Results of simulation indicated that for all the soils, water content
was more in first layer of soil. Irrigation cycle was 48 hrs and adequate water content was available in the active
root zone of the green pepper. Another result of this study showed that if the drip fertigation system designs
properly, it will reduce drainage water below the crop root zone. Final result of simulation showed that in all
types of soils amount of percolation from drainage boundary was less than one percent of applied water
IgG1 and IgG2a Profile of Serum Antibodies to Leishmania major Amastigote in BALB/c and C57BL/6Mice
It is well accepted that in experimental model of Leishmania major infection, BALB/c mice mount a Th2 response and produce IgG1 predominantly whereas C57BL/6mice enhance Th1 response with the biased production of IgG2a antibodies. Therefore, screening for parasite antigens on the basis of reactivity with sera from infected susceptible or resistant mice might be used for the identification of Th1- or Th2-inducing antigens.
In this study, the antigenic profile of Leishmania majoramastigote that induce IgG1 or IgG2a isotypes in infected BALB/c or C57BL/6 mice were compared.
Western blot analyses revealed that 27, 40, 43, 45 and 114 kDa proteins elicited IgG1 and not IgG2a in both BALB/c and C57BL/6 mice and 55 kDa protein was recognized exclusively by IgG1 of BALB/c mice sera. On the contrary, the bands corresponding to proteins with molecular weights (MW) of 30, 35, 52, 58 and 66 were intensively immunostained with IgG2a from C57BL/6 mice which made them potential candidates for eliciting Th1 response.
In conclusion, the results showed that the generation of the immune responses depended on the mouse strain and some leishmanial antigens had an intrinsic potency to elicit Th2 responses
Interaction of sperm with endometrium can regulate genes involved in endometrial receptivity pathway in mice: An experimental study
Background: Many researchers consider implantation and endometrial receptivity as pertinent issues in reproductive science. Although, several experiments have been performed and their results evaluated, yet there is no confirmed evidence about the related factors and the role of sperm in endometrial receptivity. Objective: To investigate the effect of the sperm-endometrium interaction in regulating genes involved in the endometrial receptivity pathway.
Materials and Methods: In this experimental study, 10 male and 30 female NMRI mice were included, and half of the male cases were vasectomized. The subjects were divided into two groups as follows; group 1 (case) comprised of 15 females mated with 5 non-vasectomized male mice, while group 2 (control) consisted of 15 females mated with 5 vasectomized males. Cases were sacrificed and assessed after 36 hr and the endometrial tissue was extracted and kept at -80°C until the next use. The expression of the endometrial receptivity pathway genes, including VEGF, HBEGF, FGF2, EGF, LIF, LIFR, HOXA10, MUC1, PGR, and CSF, was examined in both groups. For statistical analysis, an independent samples test (Mean ± SD) was used.
Results: The mRNA levels of LIF (p = 0.045), LIFR (p = 0.040), MUC1 (p = 0.032), VEGF (p = 0.022), EFG (p = 0.035), and FGF2 (p = 0.040) were significantly upregulated in the case group compared with the control group.
Conclusion: Finally, seminal plasma was observed to be effective in expressing the involved genes in the successful implantation pathway, including LIF, LIFR, MUC1, VEGF, EGF, and FGF2.
Key words: Endometrial receptivity, Sperm, Gene expression, Mice
Acetylated nanocellulose for single-component bioinks and cell proliferation on 3D-printed scaffolds
Nanocellulose has been demonstrated as a suitable material for cell culturing, given its similarity to extracellular matrices. Taking advantage of the shear thinning behavior, nanocellulose suits three-dimensional (3D) printing into scaffolds that support cell attachment and proliferation. Here, we propose aqueous suspensions of acetylated nanocellulose of a low degree of substitution for direct ink writing (DM). This benefits from the heterogeneous acetylation of precursor cellulosic fibers, which eases their deconstruction and confers the characteristics required for extrusion in DIW. Accordingly, the morphology of related 3D printed architectures and their performance during drying and rewetting as well as interactions with living cells are compared with those produced from typical unmodified and TEMPO-oxidized nanocelluloses. We find that a significantly lower concentration of acetylated nanofibrils is needed to obtain bioinks of similar performance, affording more porous structures. Together with their high surface charge and axial aspect, acetylated nanocellulose produces dimensionally stable monolithic scaffolds that support drying and rewetting, required for packaging and sterilization. Considering their potential uses in cardiac devices, we discuss the interactions of the scaffolds with cardiac myoblast cells. Attachment, proliferation, and viability for 21 days are demonstrated. Overall, the performance of acetylated nanocellulose bioinks opens the possibility for reliable and scaleup fabrication of scaffolds appropriate for studies on cellular processes and for tissue engineering.Peer reviewe
Expression of Leishmania major LmSTI1 in Yeast Pichia Pastoris
Background: Leishmania major LmSTI1 is a conserved protein among different species of leishmania, and expressed in both amastigote and promastigote forms of L. major life cycle. It has previously been expressed in bacterial systems.Materials and Methods: To express LmSTI1 in the methylotrophic yeast Pichia pastoris (P. pastoris), the shuttle vector pPICZA containing gene lmsti1 was constructed under the control of the AOX1 promoter. The recombinant vector was electro-transformed into P. pastoris, and induced by 0.5% methanol in the buffered medium. The expression of the LmSTI1 protein was visualized in the total soluble protein of P. pastoris by 12% SDS-PAGE, and further confirmed by Western blotting with L.major-infected mouse sera and HRP-conjugated goat anti-mouse IgG as the first and secondary antibodies, respectively.Results: The expression level was 0.2% of total soluble proteins.Conclusion: It might be possible to use this formulation as a whole yeast candidate vaccine against cutaneous leishmanization
Phagocytosis of Leishmania Major Parasites by Murine Macrophages; what is happening under a Microscope?
The promastigotes of Leishmania major (MRHO/IR/75/ER) were grown as previously described [1]. J774A.1 which is a murine macrophage Cell Line was purchased from Pasteur Institute of Iran and cultured using Roswell Park Memorial Institute medium (RPMI-1640) (Biowest, France) enriched with 10% heat-inactivated Fetal Bovine Serum (FBS) (Gibco, USA) with 2 mM L.glutamine (Sigma, Australia) and 1% penicillin/streptomycin (Gibco, USA). 7 × 106 macrophage cells were seeded in a T75 cell culture flask (SPL life sciences, South Korea). After 24 hours, 7 × 107 stationary phase promastigotes of L. major were added to the T75 flask containing J774A.1 macrophage cells. The video was recorded immediately and 3 hours after the infection of macrophages with L. major parasites under an inverted microscope (OPTIKA, Italy) with Samsung A13 mobile phone camera (Samsung, USA)
Direct Ink Writing of Biocompatible Nanocellulose and Chitosan Hydrogels for Implant Mesh Matrices
Direct ink writing via single or multihead extrusion is used to synthesize layer-by-layer (LbL) meshes comprising renewable polysaccharides. The best mechanical performance (683 ± 63 MPa modulus and 2.5 ± 0.4 MPa tensile strength) is observed for 3D printed structures with full infill density, given the role of electrostatic complexation between the oppositely charged components (chitosan and cellulose nanofibrils). The LbL structures develop an unexpectedly high wet stability that undergoes gradual weight loss at neutral and slightly acidic pH. The excellent biocompatibility and noncytotoxicity toward human monocyte/macrophages and controllable shrinkage upon solvent exchange make the cellular meshes appropriate for use as biomedical implants.Peer reviewe
Bioinks from all-natural Pickering emulgels co-stabilized by cationic CNC and inclusion complexes formed by α-cyclodextrin
Direct ink writing is especially relevant to the biomedical field due to the customizable extrusion and the possibility of creating pre-designed architectures. Abundant natural polymers are sustainable and biocompatible alternatives to synthetic and persistent polymers. The printing of pure nanocellulose suspensions proves difficult due to low solid loadings, high shrinkage, as well as non-fitting rheology. Emulsion gels (emulgel) alternatives gain attention in the field owing to their favorable viscoelastic properties and the possibility of creating multiphase systems. The authors’ sulfur-free cationic cellulose nanocrystals (CNC) of low degree of substitution enable straightforward deployment in Pickering emulsions. An emulgel ink co-stabilized by cationic CNC and α-cyclodextrin is introduced as an interfacial inclusion complex. All ink components are natural and biodegradable compounds. The produced emulgel inks allow for high fidelity printing and minimum shrinkage upon drying that relaxes the need for supports, even in complex overhanging structures. A low yield stress (230–270 Pa) facilitates the inclusion of cells for biomedical applications into the formulation. The emulgel can be tuned to the desired rheological properties and be equipped with both polar and apolar compounds due to the biphasic system, making it a promising platform for biocompatible additive manufacturing
Subcutaneous Immunization with Recombinant Lactococcus lactis Expressing F1S1 Fusion Protein Induces Systemic and Mucosal Immune Responses in BALB/C Mice
Background:Lactic acid bacteria such as Lactococcus (L.) lactis are powerful tools that can function as live delivery vectors and heterologous protein expression hosts in development of novel vaccines. Pertussis toxin (PT) and filamentous hemagglutinin (FHA) are important virulence factors of Bordetella (B.) pertussis and constitute the major components of commercially available acellular pertussis (aP) vaccines. The purpose of the present study was to express F1S1 fusion protein, consisted of the N-terminal region of Si subunit from PT and FHA type 1 immunodominant domain by L. lactis and to evaluate its immunogenicity. Methods: The fusion gene composed of sequences encoding the F1s1 and the signal peptide of usp45 fragments (SECF1S1) was codon optimized for protein production in L. lactis and was synthesized and inserted in-frame inside pNZ8149 plasmid. The resulting pNZ8149-SECF1S1 construct was introduced by electroporation into L. lactis cells (LL-F1S1). BALB/c mice were subcutaneously immunized with LL-F1S1 or commercial DTaP vaccine. The immune responses were investigated. Results: The LL-F1S1-immunized mice produced significant levels of specific IFN-g compared to their respective controls and DTaP-immunized mice. The F1S1- specific IgG antibody response was lower in LL-F1S1-immunized mice while the IgG2a/IgG1 ratio was higher in this group compared to the DTaP-immunized mice. Moreover, anti-F1S1 IgA antibodies were only detected in the lung homogenates of the LL-F1S1immunized mice, suggesting the induction of a mucosal immune response. Conclusions: These results indicate the feasibility of expression of F1S1 fusion protein in L. lactis. This recombinant bacterium could induce mucosal and Th1-type systemic immune responses following subcutaneous administration
Subcutaneous administration of a fusion protein composed of pertussis toxin and filamentous hemagglutinin from Bordetella pertussis induces mucosal and systemic immune responses
Objective(s): After decades of containment, pertussis disease, caused by Bordetella pertussis seems to be re-emerging and still remains a major cause of reported vaccine-preventable deaths worldwide. The current licensed whole-cell vaccines display reactogenicity while acellular vaccines are expensive and do not induce Th1-type immune responses that are required for optimum protection against the disease. Thus, there is an urgent need to develop new vaccines and the recombinant technology seems to be the method of choice for this purpose. The present study was an attempt to develop a new, simplified, cost-effective and well-defined vaccine against Bordetella pertussis, with capacity to induce a Th1 response. Materials and Methods: A fusion DNA fragment encoding the N-terminal region of pertussis toxin S1 subunit and filamentous hemagglutinin type 1 immunodominant domain was constructed and the corresponding fusion protein (F1S1) was produced in Escherichia coli. F1S1 in conjunction with imiquimod was administered by subcutaneous (SC) and intranasal (IN) routes to BALB/c mice. Results: This vaccine formulation could elicit high levels of IFN-γ, serum IgG (with higher IgG2a/IgG1 ratio) and lung IgA after the SC and, to a lesser extent, following the IN administration. Conclusion: Our results indicate that the above-mentioned important proteins of B. pertussis could be successfully produced in E. coli as a single fusion protein. Furthermore, this protein could induce proper systemic and mucosal immune responses after administration via SC or IN routes
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