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1.
Hydrobiologia - The genus Rutilus is widespread in the western and central Palearctic region. In the Caspian Sea, the taxonomic status of different populations of Rutilus lacustris has...  相似文献   
2.
ObjectivesTyphoid fever is caused by Salmonella enterica serovar Typhi. OmpC, OmpF and OmpA, the three major outer membrane proteins (OMPs), could serve as vaccine candidates.MethodsThe porins antigenicity was predicted in silico. The OMP genes were amplified, cloned and expressed. Sero-reactivities of the recombinant proteins purified by denaturing method were assayed by ELISA. BALB/c mice were immunized with the recombinant porins followed by bacterial challenge.ResultsBacterial challenge of the animal model brought about antibody triggering efficacy of the antigen in OmpF > OmpC > OmpA order. Experimental findings validated the in silico results. None of the antigens had synergic or antagonistic effects on each other from immune system induction points of view. Despite their high immunogenicity, none of the antigens was protective. However, administration of two or three antigens simultaneously resulted in retardation of lethal effect. Porins, in addition to their specific functions, share common functions. Hence, they can compensate for each other's functions.ConclusionsThe produced antibodies could not eliminate the pathogenicity by blockade of one or some of the antigens. Porin antigens are not suitable vaccine candidates alone or in denatured forms. Native forms of the antigens maybe studied for protective immunogenicity.  相似文献   
3.

Background

T-cells play an important role in the immune response and are activated in response to the presentation of antigens bound to major histocompatibility complex (MHC) molecules participating with the T-cell receptor (TCR). T-cell receptor complexes also contain four CD3 (cluster of differentiation 3) subunits. The TCR-CD3 complex is vital for T-cell development and plays an important role in intervening cell recognition events. Since microRNAs (miRNAs) are highly stable in blood serum, some of which may target CD3 molecules, they could serve as good biomarkers for early cancer detection. The aim of this study was to see whether there is a relationship between cancers and the amount of miRNAs -targeted CD3 molecules.

Methods

Bioinformatics tools were used in order to predict the miRNA targets for these genes. Subsequently, these highly conserved miRNAs were evaluated to see if they are implicated in various kinds of cancers. Consequently, human disease databases were used. According to the latest research, this study attempted to investigate the possible down- or upregulation of miRNAs cancer patients.

Results

We identified miRNAs which target genes producing CD3 subunit molecules. The most conserved miRNAs were identified for the CD3G gene, while CD247 and CD3EAP genes had the least number and there were no conserved miRNA associated with the CD3D gene. Some of these miRNAs were found to be responsible for different cancers, following a certain pattern.

Conclusions

It is highly likely that miRNAs affect the CD3 molecules, impairing the immune system, recognizing and destroying cancer tumor; hence, they can be used as suitable biomarkers in distinguishing cancer in the very early stages of its development.  相似文献   
4.
Molecular Biology Reports - Understanding the genetic diversity and relationships between genotypes is an effective step in designing effective breeding programs. Insertional polymorphisms of...  相似文献   
5.

Objectives

To engineer the yeast Saccharomyces cerevisiae for the heterologous production of linalool.

Results

Expression of linalool synthase gene from Lavandula angustifolia enabled heterologous production of linalool in S. cerevisiae. Downregulation of ERG9 gene, that encodes squalene synthase, by replacing its native promoter with the repressible MET3 promoter in the presence of methionine resulted in accumulation of 78 µg linalool l?1 in the culture medium. This was more than twice that produced by the control strain. The highest linalool titer was obtained by combined repression of ERG9 and overexpression of tHMG1. The yeast strain harboring both modifications produced 95 μg linalool l?1.

Conclusions

Although overexpression of tHMG1 and downregulation of ERG9 enhanced linalool titers threefold in the engineered yeast strain, alleviating linalool toxicity is necessary for further improvement of linalool biosynthesis in yeast.
  相似文献   
6.
In this study, a nanoemulsion containing mebudipine [composed of ethyl oleate (oil phase), Tween 80 (T80), Span 80 (S80) (surfactants), polyethylene glycol 400, ethanol (cosurfactants), and deionized water] was prepared with the aim of improving its bioavailability for an effective antihypertensive therapy. Particle size of the formulation was measured by dynamic light scattering. Then, artificial neural networks were used in identifying factors that influence the particle size of the nanoemulsion. Three variables, namely, amount of surfactant system (T80?+?S80), amount of polyethylene glycol, and amount of ethanol as cosurfactants, were considered as input values and the particle size was used as output. The developed model showed that all the three inputs had some degrees of effect on particles size: increasing the value of each input decreased the size. Furthermore, amount of surfactant was found to be the dominant factor in controlling the final particle size of nanoemulsion.

Communicated by Ramaswamy H. Sarma  相似文献   

7.
Coronary artery disease (CAD) is a multicellular disease characterized by chronic inflammation. Peripheral blood-mononuclear cells (PBMCs), as a critical component of immune system, actively cross-talk with pathophysiological conditions induced by endothelial cell injury, reflecting in perturbed PBMC expression. STAT1 is believed to be relevant to CAD pathogenesis through regulating key inflammatory processes and modulating STAT1 expression play key roles in fine-tuning CAD-related inflammatory processes. This study evaluated PBMC expressions of STAT1, and its regulators (miR-150 and miR-223) in a cohort including 72 patients with CAD with significant ( ≥ 50%) stenosis, 30 patients with insignificant ( < 50%) coronary stenosis (ICAD), and 74 healthy controls, and assessed potential of PBMC expressions to discriminate between patients and controls. We designed quantitative real-time polymerase chain reaction (RT-qPCR) assays and identified stable reference genes for normalizing PBMC quantities of miR-150, miR-223, and STAT1 applying geNorm algorithm to six small RNAs and five mRNAs. There was no significant difference between CAD and ICAD patients regarding STAT1 expression. However, both groups of patients had higher levels of STAT1 than healthy controls. miR-150 and miR-223 were differently expressed across three groups of subjects and were downregulated in patients compared with healthy controls, with the lowest expression levels being observed in patients with ICAD. ROC curves suggested that PBMC expressions may separate between different groups of study subjects. PBMC expressions also discriminated different clinical manifestations of CAD from ICADs or healthy controls. In conclusion, the present study reported PBMC dysregulations of STAT1, miR-150, and miR-223, in patients with significant or insignificant coronary stenosis and suggested that these changes may have diagnostic implications.  相似文献   
8.
The highly potent but modestly selective N-(2-amino-4-methoxy-benzothiazol-7-yl)-N-ethyl-acetamide derivative 2 was selected as the starting point for the design of novel selective A2B antagonists, due to its excellent potency, and good drug-like properties. A series of compounds containing nonaromatic amides or ureas of five- or six-membered rings, and also bearing an m-trifluoromethyl-phenyl group (shown to impart superior potency) was prepared and evaluated for their selectivity against the A2A and A1 receptors. This work resulted in the identification of compound 30, with excellent potency and high selectivity against both A2A and A1 receptors.  相似文献   
9.
p130(cas) (Crk-associated substrate) is a docking protein that is involved in assembly of focal adhesions and concomitant cellular signaling. It plays a role in physiological regulation of cell adhesion, migration, survival, and proliferation, as well as in oncogenic transformation. The molecule consists of multiple protein-protein interaction motifs, including a serine-rich region that is positioned between Crk and Src-binding sites. This study reports the first structure of a functional domain of Cas. The solution structure of the serine-rich region has been determined by NMR spectroscopy, demonstrating that this is a stable domain that folds as a four-helix bundle, a protein-interaction motif. The serine-rich region bears strong structural similarity to four-helix bundles found in other adhesion components like focal adhesion kinase, alpha-catenin, or vinculin. Potential sites for phosphorylation and interaction with the 14-3-3 family of cellular regulators are identified in the domain and characterized by site-directed mutagenesis and binding assays. Mapping the degree of amino acid conservation onto the molecular surface reveals a patch of invariant residues near the C terminus of the bundle, which may represent a previously unidentified site for protein interaction.  相似文献   
10.
The docking protein p130Cas becomes phosphorylated upon cell adhesion to extracellular matrix proteins, and is thought to play an essential role in cell transformation. Cas transmits signals through interactions with the Src-homology 3 (SH3) and Src-homology 2 domains of FAK or v-Crk signaling molecules, or with 14-3-3 protein, as well as phosphatases PTP1B and PTP-PEST. The large (130kDa), multi-domain Cas molecule contains an SH3 domain, a Src-binding domain, a serine-rich protein interaction region, and a C-terminal region that participates in protein interactions implicated in antiestrogen resistance in breast cancer. In this study, as part of a long-term goal to examine the protein interactions of Cas by X-ray crystallography and nuclear magnetic resonance spectroscopy, molecular constructs were designed to express two adjacent domains, the serine-rich domain and the Src-binding domain, that each participate in intermolecular contacts dependent on protein phosphorylation. The protein products are soluble, homogeneous, monodisperse, and highly suitable for structural studies to define the role of Cas in integrin-mediated cell signaling.  相似文献   
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