Tunable Plasmonic Silver Nanodomes for Surface-Enhanced Raman Scattering

Surface-enhanced Raman scattering (SERS) is an emerging analytical method used in biological and non-biological structure characterization. Since the nanostructure plasmonic properties is a significant factor for SERS performance, nanostructure fabrication with tunable plasmonic properties are crucial in SERS studies. In this study, a novel method for fabrication of tunable plasmonic silver nanodomes (AgNDs) is presented. The convective-assembly method is preferred for the deposition of latex particles uniformly on a regular glass slide and used as a template for polydimethylsiloxane (PDMS) to prepare nanovoids on a PDMS surface. The obtained nanovoids on the PDMS are used as a mold for AgNDs fabrication. The nanovoids are filled with Ag deposition by the electrochemical method to obtain metallic AgNDs. Scanning electron microscopy (SEM) and atomic force microscopy (AFM) are used for characterization of the structural properties of all fabricated AgNDs. The optical properties of AgNDs are characterized with the evaluation of SERS activity of 4-aminothiphonel and rhodamine 6G. In addition to experimental characterizations, the finite difference time domain (FDTD) method is used for the theoretical plasmonic properties calculation of the AgNDs. The experimental and theoretical results show that the SERS performance of AgNDs is strongly dependent on the heights and diameters of the AgNDs.     

Application of artificial neural network and machine learning algorithms for modeling the in vitro regeneration of chickpea (Cicer arietinum L.)

Plant Cell, Tissue and Organ Culture (PCTOC) - In vitro whole plant regeneration protocol of desi chickpea was established followed by generating the model prediction using different machine...     

The potential usage of caffeic acid phenethyl ester (CAPE) against chemotherapy‐induced and radiotherapy‐induced toxicity

Protection of the patients against the side effects of chemotherapy and radiotherapy regimens has attracted increasing interest of clinicians and practitioners. Caffeic acid phenethyl ester (CAPE), which is extracted from the propolis of honeybee hives as an active component, specifically inhibits nuclear factor κB at micromolar concentrations and show ability to stop 5‐lipoxygenase‐catalysed oxygenation of linoleic acid and arachidonic acid. CAPE has antiinflammatory, antiproliferative, antioxidant, cytostatic, antiviral, antibacterial, antifungal and antineoplastic properties. The purpose of this review is to summarize in vivo and in vitro usage of CAPE to prevent the chemotherapy‐induced and radiotherapy‐induced damages and side effects in experimental animals and to develop a new approach for the potential usage of CAPE in clinical trial as a protective agent during chemotherapy and radiotherapy regimens. Copyright © 2012 John Wiley & Sons, Ltd.     

Recombinant Tandem Repeated Expression of S3 and SΔ3 Antimicrobial Peptides

Background:Antimicrobial peptides (AMPs) are promising candidates for new generations of antibiotics to overcome the threats of multidrug-resistant infections as well as other industrial applications. Recombinant expression of small peptides is challenging due to low expression rates and high sensitivity to proteases. However, recombinant multimeric or fusion expression of AMPs facilitates cost-effective large-scale production of AMPs. In This project, S3 and SΔ3 AMPs were expressed as fusion partners. S3 peptide is a 34 amino acid linear antimicrobial peptide derived from lipopolysaccharide (LPS) binding site of factor C of horseshoe crab hemolymph and SΔ3 is a modified variant of S3 possessing more positive charges.Methods:Two copy tandem repeat of the fusion protein (named as SΔ3S3-2mer-GS using glycine- serine linker was expressed in E. coli. BL21 (DE3). After cell disruption and solubilization of inclusion bodies, the protein was purified by Ni -NTA affinity chromatography. Antimicrobial activity and cytotoxic properties of purified SΔ3S3-2mer-GS were compared with a previously produced tetramer of S3 with the same glycine- serine linker (S3-4mer-GS) and each of monomeric blocks of S3 and SΔ3. Results:SΔ3S3-2mer-GS was successfully expressed with an expression rate of 26%. The geometric average of minimum inhibitory concentration (MIC GM) of SΔ3S3-2mer-GS was 28%, 34%, and 57% lower than SΔ3, S3-4mer-GS, and S3, respectively. SΔ3S3-2mer-GS had no toxic effect on eukaryotes human embryonic kidney cells at its MIC concentration.Conclusion:tandem repeated fusion expression strategy could be employed as an effective technique for recombinant production of AMPs.Key Words: Antimicrobial Peptide, S3, SΔ3 Fusion Expression, Tandem Repeat Expression     

The Effect of TIGAR Knockdown on Apoptotic and Epithelial‐Mesenchymal Markers Expression in Doxorubicin‐Resistant Non‐Small Cell Lung Cancer A549 Cell Lines

Resistance to chemotherapeutic drugs is a critical problem in cancer therapy, but the underlying mechanism has not been fully elucidated. TP53‐induced glycolysis regulatory phosphatase (TIGAR), an important glycolysis and apoptosis regulator, plays a crucial role in cancer cell survival by protecting cells against oxidative stress‐induced apoptosis. In the present study, we investigated whether TIGAR is involved in epithelial‐mesenchymal transition (EMT) in doxorubicin (DOX)‐resistant human non‐small cell lung cancer (NSCLC), A549/DOX cells. We found that the expression of TIGAR was significantly higher in A549/DOX cells than in the parent A549 cell lines. siRNA‐mediated TIGAR knockdown reduced migration, viability and colony survival of doxorubicin‐resistant lung cancer cells. Also, TIGAR knockdown decreased pro‐survival protein Bcl‐2 and increased pro‐apoptotic Bax and cleaved poly (ADP‐ribose) polymerase (PARP). Moreover, TIGAR depletion significantly up‐regulated both caspase‐3 and caspase‐9 expression. Furthermore, TIGAR depletion up‐regulated the expression of E‐cadherin and down‐regulated the expression of vimentin. These results indicate that TIGAR knockdown may inhibit EMT in doxorubicin (DOX)‐resistant human NSCLC and may represent a therapeutic target for a non‐small lung cancer cells chemoresistance.     

Immunocytochemical detection of neuronal nitric oxide synthase (nNOS)-IR in embryonic rat stomach between days 13 and 21 of gestation.

In this study, the localization and appearance of neuronal nitric oxide synthase-immunoreactive (nNOS-IR) nerve cells and their relationships with the developing gastric layers were studied by immunocytochemistry techniques and light microscopy in embryonic rat stomach. The stomachs of Wistar rat embryos aged 13-21 days were used. The first nerve cells containing nNOS-IR were seen on embryonic Day 14. The occurrence of mesenchymal cell condensation near nNOS-IR neuroblasts on embryonic Day 15 may reflect an active nerve element-specific mesenchymal cell induction causing the morphogenesis of muscle cells. Similarly, the appearance of glandular structures after nNOS-IR neuroblasts, on embryonic Day 18, suggests that the epithelial differentiation may depend on inputs coming from nNOS-IR neuroblasts, as well as other factors. Observation of nNOS-IR nerve fibers on embryonic Day 21 demonstrates that at this stage they contribute to nonadrenergic noncholinergic relaxation. In conclusion, depending on this study's results, it can be said that cells and tissues might be affected by NO secreted by nNOS-IR nerve cells during the development and differentiation of embryonic rat stomach.     

Triamcinolone up‐regulates GLUT 1 and GLUT 3 expression in cultured human placental endothelial cells

The placenta is a glucocorticoid target organ, and glucocorticoids (GCs) are essential for the development and maturation of fetal organs. They are widely used for treatment of a variety of diseases during pregnancy. In various tissues, GCs have regulated by glucose transport systems; however, their effects on glucose transporters in the human placental endothelial cells (HPECs) are unknown. In the present study, HPECs were cultured 24 h in the presence or absence of 0·5, 5 and 50 µmol·l^–1 of synthetic GC triamcinolone (TA). The glucose carrier proteins GLUT 1, GLUT 3 and GC receptor (GR) were detected in the HPECs. We showed increased expression of GLUT 1 and GLUT 3 proteins and messenger RNA (mRNA) levels (p < 0·05) after 24‐h cell culture in the presence of 0·5, 5 and 50 µmol·l^‐1 of TA. In contrast, GR protein and mRNA expressions were down‐regulated (p < 0·05) with 0·5, 5 and 50 µmol·l^–1 of TA 24‐h cell culture. The results demonstrate that GCs are potent regulators of placental GLUT 1 and GLUT 3 expression through GR. Excessive exposure to GCs causes maternal and fetal hypoglycemia and diminished fetal growth. We speculate that to compensate for fetal hypoglycemia and diminished fetal growth, the expression of placental endothelial glucose transporters might be increased. Copyright © 2011 John Wiley & Sons, Ltd.     

Antioxidant activity,phytochemical composition of Andricus tomentosus and its antiproliferative effect on Mia-Paca2 cell line

Molecular Biology Reports - Plant derived products are widely used in cancer treatment. Gall species has been preferred for treatment various diseases in folk medicine, but there are few studies on...