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1.
Iran J Microbiol ; 15(3): 456-461, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37448671

RESUMO

Background and Objectives: The aim of this study was to investigate the in vitro antifungal potency of the moronecidin-like peptide against Candida albicans, Candida glabrata, and Candida tropicalis. Materials and Methods: To evaluate the antifungal effect of moronecidin-like peptide, the protocol presented in CLSI M27-A3 and CLSI M27-S4 was used and the minimum inhibitory concentration was determined. Results: The minimum inhibitory effect of moronecidin-like peptide composition was 8 µg/ml for Candida tropicalis and Candida albicans and 32 µg/ml for Candida glabrata. The MIC of nystatin was determined to be 1.25 µg/ml for Candida glabrata and Candida albicans and 0.625 µg/ml for Candida tropicalis strains. The MFC composition of the moronecidin-like peptide was determined for Candida tropicalis and Candida albicans strains 8 µg/ml and for Candida glabrata strain 64 µg/ml. The results of cytotoxicity and hemolysis of the moronecidin peptide test on macrophage showed that moronecidin peptide has no cytotoxicity and toxicity properties. Conclusion: According to the results of the present study, the moronecidin-like peptide could be a new strategy in the treatment of infections caused by Candida strains. The discovery of the exact mechanism of which requires extensive clinical studies in this field.

2.
Materials (Basel) ; 14(18)2021 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-34576638

RESUMO

This paper aims to analytically derive bending equations, as well as semi-analytically predict the deflection of prismatic SMA beams in the martensite phase. To this end, we are required to employ a simplified one-dimensional parametric model considering asymmetric response in tension and compression for martensitic beams. The model takes into account the different material parameters in martensite twined and detwinned phases as well as elastic modulus depending on the progress of the detwinning process. In addition, the model considers the diverse slope of loading and unloading in martensite detwinned phases favored by tension and compression. To acquire general bending equations, we first solve the pure bending problem of a prismatic SMA beam. Three different phases are assumed in the unloading procedure and the effect of neutral fiber distance from the centerline is also considered during this stage. Then according to the pure bending solution and employing semi-analytical methods, general bending equations of an SMA beam are derived. Polynomial approximation functions are utilized to obtain the beam deflection-length relationship. To validate the attained analytical expressions, several three- and four-point bending tests were conducted for rectangular and circular SMA beams. Experimental data confirm the reasonable accuracy of the analytical results. This work may be envisaged to go deep enough in investigating the response of SMA beams under an arbitrary transverse loading and stress distribution during loading and unloading, as well as findings may be applicable to a good prediction of bending behavior.

3.
J Mech Behav Biomed Mater ; 122: 104689, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34298452

RESUMO

One-piece bearing is the latest type of total disc replacement (TDR) design that is used for the treatment of lumbar degenerative disc disease (DDD). Due to the unique properties of the shape memory polymers (SMPs), such as self-healing, shape-memory, adhesion control, and self-deployable ability, they may be a good candidate for the core of such a design. The purpose of the present study is to use an analytical method combined with a numerical analysis (finite element analysis (FEA)) to determine the mechanical responses of an SMP intervertebral disc (IVD) model, under pure torsion (axial rotation) and pure compression, two loading conditions to which natural intervertebral discs (IVDs) are subjected in vivo. We considered the SMP IVD model to be positioned at L4-L5 because most cases of lumbar DDD are reported at this segment. For the analytical method, an appropriate constitutive equation for an SMP was determined and, then, an analytical solution for the torsional response of a circular SMP IVD model, in a full cycle of stress-free strain recovery, was derived. The developed equations were implemented in finite element modeling to determine responses of the IVD disc model under pure torsion. Additionally, responses of the SMC IVD model, under a compressive load, and different conditions were determined. The analytical and FEA results were compared to experimental results give in the literature for intact lumbar spine segments as the core in a one-piece lumbar TDR. Based on this study, we suggest that SMPs can be used for TDR, as they are strong enough to bear the torsional and compressive loads that IVD is subjected through its life.


Assuntos
Degeneração do Disco Intervertebral , Disco Intervertebral , Materiais Inteligentes , Substituição Total de Disco , Fenômenos Biomecânicos , Análise de Elementos Finitos , Humanos , Disco Intervertebral/cirurgia , Vértebras Lombares/cirurgia
4.
Iran J Allergy Asthma Immunol ; 19(3): 276-288, 2020 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-32615661

RESUMO

Chenopodium album polcalcin (Che a 3) is characterized as a major cause of cross-reactivity inallergic patients to the Chenopodiaceae family. Therefore, the present study was conducted to develop a hypoallergenic Che a 3 derivatives as the candidate vaccine for type 1 allergy. Four derivatives were generated from Che a 3. The first was a mosaic peptide derivative computationally identified in Che a 3 which was coupled to keyhole limpet hemocyanin (KLH). The second one was a mutant Che a 3, and the other two derivatives included N- and C-terminal halves of Che a 3 that both coupled to KLH. The IgE-binding capacity of Che a 3 and its derivatives and also their ability to induce there combinant Che a 3 (rChe a 3)-specific IgG antibody, were determined using the enzyme-linked immune sorbent assay (ELISA). Moreover, the lymphopro liferative capacity of rChe a 3 or its derivatives and their pro-inflammatory cytokine response interleukin (IL)-5 and IL-13 were measured in the human peripheral blood mononuclear cells (PBMCs). Among all derivatives, the N-terminal half peptide and mosaic peptide exhibited the lowest IgE-binding capacity. In addition, in comparison to other antigens, KLH-coupled mosaic peptide induced the highest level of the recombinant Che a 3 (rChe a 3)-specific IgG antibody and ther Che a 3 specific-blocking IgG antibody in mice. Moreover, the mosaic peptide lacked lymphopro liferative capacity and down-regulated expression of pro-allergic IL-5 and IL-13 cytokines. Therefore, a peptide-carrier fusion vaccine, composed of the B-cell epitope coupled to the carrier, could be considered as one of the promising hypoallergenic vaccines to treat patients with allergy to low molecular weight allergens such as Che a 3.


Assuntos
Alérgenos/imunologia , Antígenos de Plantas/imunologia , Proteínas de Ligação ao Cálcio/imunologia , Imunoglobulina E/imunologia , Imunoglobulina G/imunologia , Peptídeos/imunologia , Vacinas de Subunidades Antigênicas , Adulto , Animais , Feminino , Humanos , Imunoglobulina E/sangue , Masculino , Camundongos Endogâmicos BALB C , Pessoa de Meia-Idade , Rinite Alérgica Sazonal/imunologia
5.
Cell J ; 18(2): 127-34, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27551673

RESUMO

OBJECTIVE: Lactobacilli are a group of probiotics with beneficial effects on prevention of cancer. However, there is scant data in relation with the impacts of probiotics in late-stage cancer progration, especially metastasis. The present original work was aimed to evaluate the anti-metastatic and anti-proliferative activity of lactobacillus rhamnosus supernatant (LRS) and lactobacillus crispatus supernatant (LCS) on the human cervical and colon adenocarcinoma cell lines (HeLa and HT-29, respectively). MATERIALS AND METHODS: In this experimental study, the anti-proliferative activities of LRS and LCS were determined through MTT assay. MRC-5 was used as a normal cell line. Expression analysis of CASP3, MMP2, MMP9, TIMP1 and TIMP2 genes was performed by quantitative reverse transcriptase-polymerase chain reaction (qRT-PCR), following the cell synchronization. RESULTS: Supernatants of these two lactobacilli had cytotoxic effect on HeLa, however LRS treatment was only effective on HT-29 cell line. In addition, LRS had no side-effect on normal cells. It was shown that CASP3 gene expression has been reduced after treatment with supernatants of two studied lactobacilli. According to our study, LRS and LCS are efficacious in the prevention of metastasis potency in HeLa cells with decreased expression of MMP2, MMP9 and increased expression of their inhibitors. In the case of HT-29 cells, only LRS showed this effect. CONCLUSION: Herein, we have demonstrated two probiotics which have anti-metastatic effects on malignant cells and they can be administrated to postpone late-stage of cancer disease. LRS and LCS are effective on HeLa cell lines while only the effect of LRS is significant on HT-29, through cytotoxic and anti-metastatic mechanisms. Further assessments are required to evaluate our results on the other cancer cell lines, in advance to use these probiotics in other extensive trial studies.

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