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The CRISPR system finds extensive application in molecular biology, but its continuous activity can yield adverse effects. Leveraging programmable CRISPR/Cas9 function via nano-device mediation effectively mitigates these drawbacks. The integration of RNA-sensing platforms into CRISPR thus empowers it as a potent tool for processing internal cell data and modulating gene activity. Here, an intelligent guide RNA—a cis-repressed gRNA synthetic circuit enabling efficient recognition of specific trigger RNAs—is developed. This platform carries two toehold switches and includes an inhibited CrRNA sequence. In this system, the presence of cognate trigger RNA promotes precise binding to the first toehold site, initiating a cascade that releases CrRNA to target a reporter gene (luciferase) in this study. Decoupling the CrRNA segment from the trigger RNA enhances the potential of this genetic logic circuit to respond to specific cellular circumstances, offering promise as a synthetic biology platform. Developed 'IngRNA,' an intelligent CRISPR/Cas9 system with RNA-sensing toehold switches, enabling precise gene modulation by activating CrRNA in response to specific trigger RNAs. Demonstrated effective luciferase targeting in various systems. [ABSTRACT FROM AUTHOR]

One of the recognized motor neuron degenerative disorders is amyotrophic lateral sclerosis (ALS). By now, several mutations have been reported and linked to ALS patients, some of which are induced by mutations in the human superoxide dismutase (hSOD1) gene. The ALS-provoking mutations are located throughout the structure of hSOD1 and promote the propensity to aggregate. Despite numerous investigations, the underlying mechanism related to the toxicity of mutant hSOD1 through the gain of a toxic function is still vague. We surveyed two mutant forms of hSOD1 by removing and adding cysteine at positions 146 and 72, respectively, to investigate the biochemical characterization and amyloid formation. Our findings predicted the harmful and destabilizing impact of two SOD1 mutants using multiple programs. The specific activity of the wild-type form was about 1.42- and 1.92-fold higher than that of C146R and G72C mutants, respectively. Comparative structural studies using CD spectropolarimetry, and intrinsic and ANS fluorescence showed alterations in secondary structure content, exposure of hydrophobic patches, and structural compactness of WT-hSOD1 vs. mutants. We demonstrated that two mutants were able to promote amyloid-like aggregates under amyloid induction circumstances (50-mM Tris–HCl pH 7.4, 0.2-M KSCN, 50-mM DTT, 37 °C, 190 rpm). Monitoring aggregates were done using an enhancement in thioflavin T fluorescence and alterations in Congo red absorption. The mutants accelerated fibrillation with subsequently greater fluorescence amplitude and a shorter lag time compared to WT-SOD1. These findings support the aggregation of ALS-associated SOD1 mutants as an integral part of ALS pathology. [ABSTRACT FROM AUTHOR]

Most of the previously reported fluorescent organic probes for cancer cell and tumor imaging have significant limitations including chemical toxicity, structural instability, low Stokes shift value, and the inability for selective accumulations in tumors during in vivo imaging. To overcome the mentioned challenges, we synthesized the fluorescent probes with protected polar functional groups to enhance the non‐toxicity nature and increase the selectivity toward tumors. In addition, the structural rigidity of the fluorescent probes was increased by embedding aromatic rings in the probe structure. This issue enables us to obtain ultrabright cell images due to enhanced fluorescence quantum yield (ΦFL) values. After synthesis and spectral characterizations, the applicability of two furan‐based and imidazole‐based fluorescent probes (abbreviated as DCPEF and DBPPI, respectively) was investigated for ultrabright in vitro and in vivo imaging of cancer cells. The probe DCPEF shows the ΦFL value of 0.946 and the Stocks shift of 86 nm. In addition, probe DBPPI offers the ΦFL value of 0.400 and a Stocks shift of 150 nm. The MTT colorimetric cytotoxicity assay showed that probe DCPEF has minimal effects against HT‐29 (cancer) and Vero (normal) cells. The probe DCPEF produced ultrabright fluorescence images from HT‐29 cells. In addition, in vivo imaging of cancer cells showed that probe DCPEF selectively accumulates in the 4T1 tumor in mice. The spectral and chemical stability, minimal cytotoxicity, significant Stokes shift, and high degree of selectivity for tumor cells during in vivo imaging make DCPEF an appropriate candidate to be used as a standard probe for cancer cell imaging. [ABSTRACT FROM AUTHOR]

A simple and cost‐effective approach was used to synthesize different morphologies of Linde Type L (LTL) nanozeolite. The resulting products were characterized by techniques such as X‐ray diffraction, Fourier transform infrared spectroscopy, scanning electronic microscopy, and Brunauer‐Emmett‐Teller measurements. The results showed that LTL nanozeolite was successfully synthesized, and different morphologies, including spherical‐like and disk‐shaped nanoparticles, were obtained. Then, the effect of size and morphology on the antibacterial activity of the obtained products was studied. Spherical‐like LTL nanoparticles showed higher antibacterial activity due to their larger pore volume and surface area and higher loading of biocidal zinc cations. [ABSTRACT FROM AUTHOR]

In the study, a biomimetic platform for anti-inflammatory-based treatment of atherosclerotic plaque was developed. Gliclazide (GL) as an anti-inflammasome agent was encapsulated in PLGA nanoparticles (NP), which were coated by monocyte membrane using an extrusion procedure. The size and zeta potential of the nanoghost (NG) changed to 292 and – 10 nm from 189.5 to −34.1 in the core NP. In addition, the actual size of 62.5 nm with a coating layer of 5 nm was measured using TEM. The NG was also showed a sustained release profile with the drug loading content of about 4.7%. Beside to attenuated TNFα, decrease in gene expression levels of NLRP3, MyD88, NOS, IL-1β, IL-18 and caspases 1/3/8/9 in LPS-primed monocytes exposed to NG strongly indicated remarkable inflammation control. After systemic toxicity evaluation and pharmacokinetic analysis of NP and NG, intravenous NG treatment of rabbits with experimentally induced atherosclerosis revealed remarkably less plaque lesions, foam cells, lipid-laden macrophages, and pathological issues in tunica media of aorta sections. Higher expression of CD163 than CD68 in aorta of NG-treated rabbits strongly reveals higher M2/M1 macrophage polarization. The bio/hemocompatible, biomimetic and anti-inflammatory NG can be considered as a potential platform for immunotherapy of particularly atherosclerosis in the field of personalized medicine. [ABSTRACT FROM AUTHOR]

In the study, a biomimetic platform for anti-inflammatory-based treatment of atherosclerotic plaque was developed. Gliclazide (GL) as an anti-inflammasome agent was encapsulated in PLGA nanoparticles (NP), which were coated by monocyte membrane using an extrusion procedure. The size and zeta potential of the nanoghost (NG) changed to 292 and – 10 nm from 189.5 to −34.1 in the core NP. In addition, the actual size of 62.5 nm with a coating layer of 5 nm was measured using TEM. The NG was also showed a sustained release profile with the drug loading content of about 4.7%. Beside to attenuated TNFα, decrease in gene expression levels of NLRP3, MyD88, NOS, IL-1β, IL-18 and caspases 1/3/8/9 in LPS-primed monocytes exposed to NG strongly indicated remarkable inflammation control. After systemic toxicity evaluation and pharmacokinetic analysis of NP and NG, intravenous NG treatment of rabbits with experimentally induced atherosclerosis revealed remarkably less plaque lesions, foam cells, lipid-laden macrophages, and pathological issues in tunica media of aorta sections. Higher expression of CD163 than CD68 in aorta of NG-treated rabbits strongly reveals higher M2/M1 macrophage polarization. The bio/hemocompatible, biomimetic and anti-inflammatory NG can be considered as a potential platform for immunotherapy of particularly atherosclerosis in the field of personalized medicine. [ABSTRACT FROM AUTHOR]

Recombinant human growth hormone (rhGH) is a therapeutic protein, associated with various human diseases, such as growth hormone deficiency. One of the interesting issues in the formulation of therapeutic proteins is excipients like disaccharides. In the current study, we try to compare the effect of sucrose and trehalose on the structure of rhGH in the liquid state at 25°C and 55°C. We use spectroscopic techniques including intrinsic and extrinsic fluorescence, Fourier‐transform infrared (FTIR), circular dichroism (CD), dynamic light scattering (DLS), and time‐resolved fluorescence. FTIR shows a slight change in the secondary structure of rhGH in presence of the sugars as sucrose is more effective than trehalose. Fluorescence investigations also confirm the enhancements of folding of rhGH and fluorescein isothiocyanate (FITC)‐rhGH in presence of sucrose (1.5‐fold more than trehalose). Also, we studied sucrose's effect on the rete of aggregation of rhGH using spectroscopy of Congo red, and fluorescence imaging of thioflavin T (ThT)‐treated samples. It can be suggested that sucrose facilitates the amyloid formation of rhGH during 20 days of incubation at 37°C. This study will help to understand the growth hormone structural behavior in the liquid state in the presence of sucrose and trehalose in vitro. [ABSTRACT FROM AUTHOR]

Biocompatible nanoparticles have attracted considerable attention as cellular antioxidant agents for the improvement of new therapeutics for several and diverse oxidative stress related disorders. Here, it is shown that the biocompatible cell membrane@gold nanoparticle displays catalase‐mimic behavior by decomposing H2O2. This interesting behavior can be used for cell protection against induced oxidative injury by reactive oxygen species (ROS). So, after characterizing this novel biocompatible nanostructure, the protective effect of cell membrane@AuNPs pretreatment in front of a well‐defined oxidative stress‐inducing chemotherapy drug, doxorubicin (Dox) is assessed. Doxorubicin pretreatment significantly reduces the intracellular ROS production. Similarly, a reduction in the levels of DNA oxidative damage, as measured with the AO/EB staining, is also observed. Obtained results would support that this novel nanostructure can show how a pharmacological agent can be used against oxidative stress‐mediated diseases. [ABSTRACT FROM AUTHOR]

In this study, a sensitive and rapid chemiluminescence (CL) approach was developed to determine the lowest concentration of urea in the luminescent system of bioluminescent earthworms based on the urea reaction with luciferin, a common substrate for bioluminescent earthworms. To this end, response surface methodology (RSM) was utilized through a Box–Behnken design (BBD) to optimize the key variables such as luciferin (2 × 10–4–2 × 10−2 M), urea (1 × 10–5–1 × 10–3 M), and the mixture of hydrogen peroxide (H2O2) with sodium hydroxide (NaOH) as oxidant (2 × 10–4–2 × 10−2 M) and also evaluate their interactive effects on the CL emission. The linear response of CL intensity was detected in the urea concentration ranging from 1 × 10–2 to 5 × 10−9 M (R2 = 0.9918). The detection limit under the optimum conditions was calculated 3.25 × 10−10 M. This rapid and facile method required low amounts of reagent for the successful detection of urea. Based on the results, these methods can offer an opportunity for the potential role of the bioluminescent earthworms in biological and non-biological analyses. [ABSTRACT FROM AUTHOR]

Mycotoxins, especially carcinogenic aflatoxins (AFs), AFs B1-and-M1, are common contaminants of foodchains, damaging exposed hosts. We analyzed the effects of naturally-occurring levels of AFB1-and-AFM1 on the rat pancreatic islets from various healthy rats and exposed for 24 and 48 h to 10–20 ng of each AF/mL. The exposed islets were analyzed for glucose-stimulated insulin secretion (GSIS), ATP content, caspase-3/7-and 9 and ROS load. This environmental toxic compound impaired islet cells quality, GSIS, ATP-and antioxidant capacity, proving sensitivity of pancreatic islets to AFs (moreso to AFB1), thereby clarifying the possible underlying mechanisms of AFs in endocrine disorders, primarily type-2 diabetes. [ABSTRACT FROM AUTHOR]

The aggregation of misfolded SOD1 proteins in neurodegenerative illnesses is a key pathological hallmark in amyotrophic lateral sclerosis (ALS). SOD1 is stabilized and enzymatically activated after binding to Cu/Zn and forming intramolecular disulfide. SOD1 aggregation/oligomerization is triggered by the dissociation of Cu and/or Zn ions. Therefore, we compared the possible effects of ALS-associated point mutations of the holo/apo forms of WT/I149T/V148G SOD1 variants located at the dimer interface to determine structural characterization using spectroscopic methods, computational approaches as well as molecular dynamics (MD) simulations. Predictive results of computational analysis of single-nucleotide polymorphisms (SNPs) suggested that mutant SOD1 has a deleterious effect on activity and structure destabilization. MD data analysis indicated that changes in flexibility, stability, hydrophobicity of the protein as well as increased intramolecular interactions of apo-SOD1 were more than holo-SOD1. Furthermore, a decrease in enzymatic activity in apo-SOD1 was observed compared to holo-SOD1. Comparative intrinsic and ANS fluorescence results of holo/apo-WT-hSOD1 and mutants indicated structural alterations in the local environment of tryptophan residue and hydrophobic patches, respectively. Experimental and MD data supported that substitution effect and metal deficiency of mutants (apo forms) in the dimer interface may promote the tendency to protein mis-folding and aggregation, consequently disrupting the dimer–monomer equilibrium and increased propensity to dissociation dimer into SOD-monomer ultimately leading to loss of stability and function. Overall, data analysis of apo/holo SOD1 forms on protein structure and function using computational and experimental studies will contribute to a better understanding of ALS pathogenicity. [ABSTRACT FROM AUTHOR]

Different programed cell death (PCD) modalities involve protein–protein interactions in large complexes. Tumor necrosis factor α (TNFα) stimulated assembly of receptor-interacting protein kinase 1 (RIPK1)/Fas-associated death domain (FADD) interaction forms Ripoptosome complex that may cause either apoptosis or necroptosis. The present study addresses the interaction of RIPK1 and FADD in TNFα signaling by fusion of C-terminal (CLuc) and N-terminal (NLuc) luciferase fragments to RIPK1-CLuc (R1C) or FADD-NLuc (FN) in a caspase 8 negative neuroblastic SH-SY5Y cell line, respectively. In addition, based on our findings, an RIPK1 mutant (R1C K612R) had less interaction with FN, resulting in increasing cell viability. Moreover, presence of a caspase inhibitor (zVAD.fmk) increases luciferase activity compared to Smac mimetic BV6 (B), TNFα -induced (T) and non-induced cell. Furthermore, etoposide decreased luciferase activity, but dexamethasone was not effective in SH-SY5Y. This reporter assay might be used to evaluate basic aspects of this interaction as well as for screening of necroptosis and apoptosis targeting drugs with potential therapeutic application. [ABSTRACT FROM AUTHOR]

A bioluminescence-based assay for ATP can measure cell viability. Higher ATP concentration indicates a higher number of living cells. Thus, it is necessary to design an ATP sensor that is low-cost and easy to use. Gold nanoparticles provide excellent biocompatibility for enzyme immobilization. We investigated the effect of luciferase proximity with citrate-coated gold, silver, and gold–silver core–shell nanoparticles, gold nanorods, and BSA–Au nanoclusters. The effect of metal nanoparticles on the activity of luciferases was recorded by the luminescence assay, which was 3–5 times higher than free enzyme. The results showed that the signal stability in presence of nanoparticles improved and was reliable up to 6 h for analytes measurements. It has been suggested that energy is mutually transferred from luciferase bioluminescence spectra to metal nanoparticle surface plasmons. In addition, we herein report the 27-base DNA aptamer for adenosine-5′-triphosphate (ATP) as a suitable probe for the ATP biosensor based on firefly luciferase activity and AuNPs. Due to ATP application in the firefly luciferase reaction, the increase in luciferase activity and improved detection limits may indicate more stability or accessibility of ATP in the presence of nanoparticles. The bioluminescence intensity increased with the ATP concentration up to 600 µM with a detection limit of 5 µM for ATP. [ABSTRACT FROM AUTHOR]

Expression and purification of human DT-diaphorase, also referred to as NAD(P)H quinone oxidoreductase 1 (NQO1; EC. 1.6.99.2), which is a flavoprotein belongs to the family of oxidoreductases are optimized. The DT-diaphorase plays an important role in biosensor design for laboratory analysis and also developing biosensor for measurement of glucose level in blood. The aim of this study was to investigate various parameters regarding the expression of DT-diaphorase in Escherichia coli BL21 (DE3) and thermal stability of DT-diaphorase activity at different temperatures in the presence of sucrose. Expression conditions of DT-diaphorase in E. coli were optimized with an induction time (22.00 hr), induction temperature (18.00 °C) and also lactose (5.00 mM) and isopropyl ß-D-1-thiogalactopyranoside (1.00 mM) concentrations as inducers. The Km, Vmax and kcat values for NADH as a substrate were 25.50 µM, 357 µM per min and 446.40 μM mg-1 per min, respectively. Results of our research revealed that different concentrations of sucrose at 40.00 °C did not have any significant effect on enzyme structure; while, relatively significant changes, especially in the presence of sucrose (0.75 M) at 50.00 °C were observed. The results presented show that sucrose causes DT-diaphorase inactivation rate reduction and relatively little increases in thermal stability and thus, sustains its conformation against thermal unfolding. [ABSTRACT FROM AUTHOR]

Dysfunction at any regulatory point along the apoptotic signaling pathway is closely related to many diseases including cancers. The apoptotic protein expression level is an important cause of cancer-related death, and the correct degradation of apoptotic proteins is involved in tumor development. Therefore, understanding of a regulatory point that underlying cancer-related death may help the development of new strategies to overcome the clinical challenges. Here, proteasome inhibitor Bortezomib and calpain inhibitor ALLN were examined on protein levels of caspase-3, caspase-9, XIAP, and E3-ligase PARC in HEK293T cells overexpressing XIAP and caspase-9. ATP depletion and caspase-3 activation were as a consequence of Bortezomib and ALLN function. Higher numbers of PI-stained cells provided evidence of cell death by both inhibitors. Western blotting analysis showed that both ALLN and Bortezomib equally inhibited degradation of XIAP, but only ALLN was effective at inhibiting caspase proteolytic degradation. Moreover, treatment of cells with both types of inhibitors significantly increased the level of E3-ligase PARC. Our findings showed that inhibition of proteasome and calpains enhanced the level of anti-apoptotic, XIAP and PARC, and pro-apoptotic, caspase-9 and 3 proteins, which totally promote cell death significantly. [ABSTRACT FROM AUTHOR]

DNA‐functionalized gold nanoparticles (DNA‐AuNPs) hold great promise for numerous biomedical applications, especially the building of well‐defined nanosystems. Previously reported methods for the preparation of DNA‐AuNPs all rely on the use of DNA‐bearing free thiol or disulfide groups at their 3′/5′ ends. But here we report a novel polyvalent DNA‐AuNPs conjugation approach by in‐situ fast synthesis of AuNPs at the polyguanine (G12) strands. As confirmed by both TEM images and gel electrophoresis analysis, many poly G strand can form an individual anisotropic AuNP and so each AuNP functionalized with a dense layer of DNA, resulting in the formation of polyvalent (p)DNA–AuNPs. The general applicability of this novel approach was further verified in hybridization test and UV‐Vis spectroscopy results show that pDNA–AuNPs conjugation is more attractive in biomedical diagnosis and specific sequence detection like microRNA‐155 by using an extra‐strand poly G with "sticky end" that are complementary to the target sequence. [ABSTRACT FROM AUTHOR]

Non‐viral gene carriers have shown noticeable potential in gene delivery because of limited side effects, biocompatibility, simplicity, and the ability to take advantage of electrostatic interactions. However, the low transfection rate of non‐viral vectors under physiological conditions is controversial. This study aimed to decrease the transfection time using a static magnetic field. We used self‐assembled cationic polysaccharides based on dextran–stearic acid–spermine (DSASP) conjugates associated with Fe3O4 superparamagnetic nanoparticles to investigate their potential as gene carriers to promote the target delivery. Our findings illustrate that the magnetic nanoparticles are spherical with a positive surface charge and exhibit superparamagnetic behavior. The DSASP–pDNA/Fe3O4 complexes offered a strong pDNA condensation, protection against DNase degradation, and significant cell viability in HEK 293T cells. Our results demonstrated that although conjugation of stearic acid could play a role in transfection efficiency, DSASP magnetic carriers with more spermine derivatives showed better affinity between the amphiphilic polymer and the negatively charged cell membrane. [ABSTRACT FROM AUTHOR]

Tumor necrosis factor (TNF)-related apoptosis inducing ligand (TRAIL), known as a cytokine of the TNF superfamily, is considered a promising antitumor agent due to its ability to selectively induce apoptosis in a wide variety of cancer cells. However, failure of its successful translation into clinic has led to development of nano-based platforms aiming to improve TRAIL therapeutic efficacy. In this regard, we fabricated a novel TRAIL-S-layer fusion protein (S-TRAIL) conjugated with graphene quantum dots (GQDs) to benefit both the self-assembly of S-layer proteins, which leads to elevated TRAIL functional stability, and unique optical properties of GQDs. Noncovalent conjugation of biocompatible GQDs and soluble fusion protein was verified via UV–visible and fluorescence spectroscopy, size and ζ-potential measurements and transmission electron microscopy. The potential anticancer efficacy of the nanohybrid system on intrinsically resistant cells to TRAIL (HT-29 human colon carcinoma cells) was investigated by MTT assay and flow cytometry, which indicated about 80% apoptosis in cancer cells. These results highlight the potential of TRAIL as a therapeutic protein that can be extensively improved by taking advantage of nanotechnology and introduce S-TRAIL/GQD complex as a promising nanohybrid system in cancer treatment. [ABSTRACT FROM AUTHOR]

The photo-physical properties of metal nano clusters are sensitive to their surrounding medium. Fluorescence enhancement, quenching, and changes in the emitted photon properties are usual events in the sensing applications using these nano materials. Combining this sensitivity with unique properties of self-assembled structures opens new opportunities for sensing applications. Here, we synthesized gold nanoclusters by utilizing phenylalanine amino acid as both capping and reducing molecule. Phenylalanine is able to self-assemble to rod-shaped nano structure in which the π–π interaction between the aromatic rings is a major stabilizing force. Any substance as iodide anion or molecule that is able to weaken this interaction influence the fluorescence of metal nano-clusters. Since the building blocks of the self-assembled structure are made through the reaction of gold ions and phenylalanine, the oxidized products and their effect of sensing features are explored. [ABSTRACT FROM AUTHOR]

Recently, there has been a growing demand to develop portable devices for the fast detection of contaminants in food safety, healthcare, and environmental fields. Herein, two biosensing methods were designed by the use of nicotinamide adenine dinucleotide phosphate (NAD(P)H)-dependent TetX2 enzyme activity and thionine as an excellent electrochemical and colorimetric mediator/probe to monitor tetracycline (TC) in milk. The nanoporous glassy carbon electrode (NPGCE) modified with polythionine was first prepared by electrochemically and then TetX2 was immobilized onto the NPGCE using polyethyleneimine. The prepared biosensor provided a high electrocatalytic response toward NAD(P)H by significantly reducing its overpotential. The proposed biosensor exhibited a detection limit of 40 nM with a linear range of 0.1-0.8 µM for TC determination. Besides, the thionine probe was used to develop a novel colorimetric assay using a simple enzymatic color reaction within a few minutes. The limit of detection for TC was experimentally achieved as 60 nM, which was lower than the safety levels established by the World Health Organization (225 nM). The correlation between change in the color of the solution and the concentration of TC was used for quality control of milk samples, as confirmed by the standard high-performance liquid chromatography method. The results show the great potential of the proposed assays as portable instruments for on-site TC measurements. [ABSTRACT FROM AUTHOR]

The current review is a guideline for a physicist/chemist/biologist/physician in the introduction of metallic nanocluster (NC) applications and selection of a suitable one from a medical perspective. Metallic nanoclusters have gained attention during recent years owing to their advantages of superior optical characteristics, long lifetime, and biocompatibility for nanomedicine applications, including biolabeling, biosensing, catalysis, bioimaging, drug/gene delivery, and therapeutic agent in comparison to the semiconductor quantum dot analogs. Here their basic physicochemical properties are being introduced, and they are linked to biomedical opportunities. Introducing the needed concepts of noble metal‐based nanomaterials is being tried here, along with giving a correct comprehension of the reason for its use in a particular part of biomedical over the last 20 years. Moreover, in each part, a perspective is presented that can guide a researcher on how they can develop or modify new scaffolds for biomedical engineering. [ABSTRACT FROM AUTHOR]

High levels of dioxins and dioxin-like compounds in the food and their adverse effects on human health are of increasing concern. Since milk is one of the most essential human nutritional resources, the present study aims at determining dioxins and PCBs in raw milk samples from four farms in North of Iran and raw and pasteurized samples from three farms and five dairy factories in Vicinity of Tehran (capital of Iran). Total toxic equivalence (TEQ) of dioxin and PCBs have been determined, using the DR-CALUX® bioassay. Results reveal that all samples are contaminated with dioxins and PCBs, comparatively. The total dioxins and PCBs levels in raw milk samples from the north range from 4.08 to 0.97 pg/gfat and for the raw samples and pasteurized samples from Tehran Province from 1.89 to 0.63 pg/gfat and 0.1 to 0.03 pg/gfat, respectively. The mean concentration of dioxins/PCBs is higher in samples from the north of Iran. This may be because of the common method of removing domestic and agricultural disposal in this area. [ABSTRACT FROM AUTHOR]

Drug resistance is a multifactorial process involving a variety of mechanisms and genes. Taxane drug class like Docetaxel is not effective for all types' breast cancers and presents a huge clinical challenge. To improve cancer treatment outcome, it is important to distinguish which proteins can kill the cancer cells and whether the expression levels of these proteins affect treatment. Cancer cells are wildly known to be protected from apoptosis, due to low level of apoptotic protease activating factor-1 (Apaf-1) compared with normal cells. Apaf-1 is an essential protein that defines whether cytochrome c released form mitochondria remains stable or degrades. According to this hypothesis, increasing of Apaf-1 expression in MCF7 breast cancer cells was performed and Docetaxel efficacy examined. The immunoassay techniques were used to investigate Apaf-1 and cytochrome c levels, and different apoptosis assay methods applied to better understand the effect of Apaf-1 expression levels in cellular response to apoptotic stimuli by Docetaxel. Our results determined that cytoplasmic cytochrome c level elevated along with increasing Apaf-1 and MCF7 cells were sensitised to Docetaxel, suggesting that loss of Apaf-1 may cause Docetaxel-resistance in breast cancer cells through less apoptosome formation. ROS level increased in cells transfected with Apaf-1 and induced mitochondrial permeability for cytochrome c release, which subsequently promoted apoptosome formation, intrinsic apoptosis and ATP depletion. [ABSTRACT FROM AUTHOR]

NAD is mainly biosynthesized by the enzymatic action of nicotinamide phosphoribosyltransferase (NAMPT) through the salvage pathway. NAD is indispensable for the proper function and metabolism of all living cells, including cancer cells. Our previous researches revealed that inhibition of NAMPT by miRNA (miR) could suppress NAD levels and thereby hinder the growth and promotion of breast cancer (BC). Therefore, the current study was undertaken to investigate the inhibitory effects of miR-613 on NAMPT and BC cells' survival. Bioinformatics analysis and luciferase reporter assay confirmed that NAMPT 3′-untranslated region is a direct target for miR-613. The expression of miR-613 was noticed to be significantly decreased in both clinical tissue samples and BC cells by real-time PCR. Following transfection with miR-613 mimic, the expression of miR-613 was elevated in the BC cells leading to inhibition of NAMPT expression at both mRNA and protein level as measured by real-time PCR and western blotting, respectively. Inhibition of NAMPT led to a remarkable reduction in the concentration of NAD in the BC cells. The transfection also declined cell viability roughly 40% in MD Anderson-Metastatic Breast-231 (MDA-MB-231) cells. Consistently, the apoptosis rate was remarkably increased, around 65% in these cells as assayed by labeling the cells with Annexin V-fluorescein isothiocyanate (FITC) and Propidium Iodide. Targeting the NAMPT-mediated NAD salvage pathway by miR-613 is a novel approach for managing BC, which is worth further investigation. [ABSTRACT FROM AUTHOR]

Recognizing proteins that lead to a decreased efficiency of treatment in cancer cells constitutes a main goal for biomedical and biotechnological research and applications. Establishing recombinant cells that overexpress a gene of interest stably is important for treatment studies and drug/compound screening. Survivin is an anti-apoptotic protein which can be a potential candidate for regulating cell death and survival. To investigate the association between survivin increment and apoptosis rate, survivin-reconstituted HEK (HEK-S) cell was developed as in vitro model. RT-PCR and Western blot demonstrated that survivin was constitutively overexpressed in HEK-S cells. Both morphological observation and survival assay showed that HEK-S cells were significantly resistant to apoptotic stimuli. Survivin overexpression led to a decrease in caspase 3/7 activity, whereas YM155 led to a corresponding enhance of caspase activity. ROS level was decreased but ATP content increased in HEK-S cells. Also, HEK-S showed less red- fluorescence and reduced cell proliferation compared to HEK after stimulation. Resistance to laser irradiation was clearly visible as compared with control. Moreover, scratching analysis demonstrated the ability of survivin to cause neighboring cells to increase resistance to drug, whereas YM155 enhanced apoptotic rate and declined invasion in HEK-S cells. [ABSTRACT FROM AUTHOR]

Chemoresistance is the leading cause of limiting long-term treatment success in cancer cells. Anticancer drugs usually kill cells through apoptosis induction and defects in this signaling pathway lead to chemoresistance. Apoptotic protease activating factor 1 regulates cellular stress evoked by chemotherapeutic agents through facilitating apoptosome assembling but can be degraded by proteasome. This study examined the role of proteasome inhibitor Bortezomib in the cytotoxic effects of Docetaxel on MCF7 cells response and its correlation with Apaf-1 expression level. MTT assay, caspase 3/7 activity assay, propidium iodide staining, adenosine triphosphate and reactive oxygen species amount measurements were utilized to demonstrate the role of Bortezomib in Docetaxel efficacy with and without Apaf-1 overexpressing. Meanwhile, two-dimensional cell migration assay was performed by scratch wound assay. The combination of Docetaxel with Bortezomib was significantly more cytotoxic compared single drug, more effectively delayed cell growth, reduced ATP level and increased ROS production. In Apaf-1 overexpressing, Docetaxel was more efficient in preventing cell migration, however, Docetaxel plus Bortezomib were not significantly effective; and fluorescence images supported the interpretation. Our findings demonstrated MCF7 resistance to Docetaxel is due in part to low Apaf-1 level and Apaf-1 overexpression resulted in the increase of cell susceptibility to Docetaxel stimulus. We assume that proteasome inhibitor may restore apoptotic proteins like Apaf-1 and prevent the degradation of cytosolic cytochrome c released by Docetaxel, consequently triggering intrinsic apoptosis and promoting cancer cell death. Collectively, treating MCF7 breast cells with proteasome inhibitor sensitizes cells to Docetaxel-induced apoptosis and possibly overcomes chemoresistance. [ABSTRACT FROM AUTHOR]

Targeted nanoparticle platforms designed to induce cell death by apoptosis can bypass the resistance mechanisms of cancer cells. With this in mind we have constructed a new cancer-targeting peptide-functionalized nanoparticle using gold nanoparticles (AuNPs) and a thioctic acid–DMPGTVLP peptide (TA-peptide) conjugate. Morphological analysis of the nanoparticles by transmission electron microscopy showed average diameters of about 3.52 nm and 26.2 nm for the AuNP core and shell, respectively. Strong affinity toward the nucleolin receptors of breast cancer cell lines MCF-7 and T47D was observed for the TA-peptide gold nanoparticles (TAP@AuNPs) based on IC50 values. Furthermore, the nanoparticles showed excellent hemocompatibility. Quantitative results of atomic absorption showed improved uptake of TAP@AuNPs. Treatment of the cells with TAP@AuNPS resulted in greater release of cytochrome c following caspase-3/7 activation compared with free TA-peptide. The cytosolic level of adenosine triphosphate for TAP@AuNPs was higher than in controls. Higher anti-tumor efficiency was observed for TAP@AuNPs than TA-peptide compared with phosphate-buffered saline after intratumoral injection in tumor-bearing mice. It can be concluded that the design and development of a receptor-specific peptide-AuNP platform will be valuable for theranostic applications in cancer nanomedicine. [ABSTRACT FROM AUTHOR]

Exposure to environmental toxicants that affect the immune system and overall health of many mammals is mostly unavoidable. One of the more common substances is the mycotoxins, especially carcinogenic aflatoxin (AF)B1 which also causes immune suppression/dysregulation in exposed hosts. The present study analyzed the effects of naturally occurring levels of AFB1 on apoptosis of healthy bovine and camelid neonatal neutrophils (PMN) that were isolated both before and after host consumption of colostrum. Cells from bovine and camel neonates (n = 12 sets of PMN/mammal/timepoint) were exposed for 24 h to a low level of AFB1 (i.e. 10 ng AFB1/ml) and then intracellular ATP content and caspase-3, -7, and -9 activities (determined by bioluminescence) were assessed. The results indicated a significant lessening of intracellular ATP content and equivalents of luminescence intensity in AFB1-treated PMN in all studied samples, i.e. isolated pre-and post-colostrum consumption. In contrast, caspase-3, -7, and -9 activities in both pre- and post-colostrum consumption bovine and camelid PMN were noticeably increased (∼>2-fold). The damaging effects of AFB1 were more pronounced in bovine neonate PMN than in camelid ones. These results showed that camelid or bovine neonatal PMN collected pre- and post-colostrum are sensitive (moreso after consumption) to naturally occurring levels of AFB1. While merits of colostrum are well known, its failure to mitigate toxic effects of AFB1 in what would translate into a critical period in the development of immune competence (i.e. during the first few days of life in bovine and camelid calves) is surprising. The observed in vitro toxicities can help clarify underlying mechanisms of immune disorders caused by AFs in animals/humans. [ABSTRACT FROM AUTHOR]

A DNA-silver nanocluster with two distinct emissions is devised, in which this unique modality has been exploited to develop a novel nanosensor for transgenic DNA detection. TEM and fluorescence analysis revealed the formation of Ag nanoclusters with a size of around 2 nm, which exhibit dual-emissions at 550 nm (green) and 630 nm (red). Moreover, in the presence of the target sequence (CaMV 35S promoter) from the transgenic plant, the nanoclusters showed an enhancement in the green emission and a reduction in the red emission. This property provided a ratiometric-sensing platform which lacks unavoidable noises. The ratio of green to red fluorescence emission (G/R) of the nanoclusters exhibited a linear relation with the target concentration in the range 10 to 1000 nM. However, the control DNA did not affect this ratio, which clearly confirmed the selective response of the designed nanosensor. This sensing platform had a detection limit of 1.5 nM and identified the DNA of transgenic soybeans within a short time. The mechanistic evaluation of the nanoclusters further revealed the role of protonated cytosine bases in the dual emission behavior. Finally, unique features of the designed nanosensor may improve the current approaches for the development and manufacturing of GMO detection tools. [ABSTRACT FROM AUTHOR]

Background: A bacterial biosensor refers to genetically engineered bacteria that produce an assessable signal in the presence of a physical or chemical agent in the environment.Methods: We have designed and evaluated a bacterial biosensor expressing a luciferase reporter gene controlled by pbr and cadA promoters in Cupriavidus metallidurans (previously termed Ralstonia metallidurans) containing the CH34 and pI258 plasmids of Staphylococcus aureus, respectively, and that can be used for the detection of heavy metals. In the present study, we have produced and evaluated biosensor plasmids designated pGL3-luc/pbr biosensor and pGL3-luc/cad biosensor, that were based on the expression of luc+ and under the control of the cad promoter and the cadC gene of S. aureus plasmid pI258 and pbr promoter and pbrR gene from plasmid pMOL30 of Cupriavidus metallidurans.Results: We found that the pGL3-luc/pbr biosensor may be used to measure lead concentrations between 1-100 μM in the presence of other metals, including zinc, cadmium, tin and nickel. The latter metals did not result in any significant signal. The pGL3-luc/cad biosensor could detect lead concentrations between 10 nM to 10 μM.Conclusions: This biosensor was found to be specific for measuring lead ions in both environmental and biological samples. [ABSTRACT FROM AUTHOR]

The efficient carrier design for transferring therapeutic genes into target cells as well as tracking the delivered agents has attracted lots of attention in the field of DNA-based therapeutics. Here, we demonstrate this concept by a fast and facilitated method using BSA gold nanocluster (BSA AuNcs) conjugated with chimeric peptide with ability of DNA binding/packaging, endosome disruption and cell nuclear localization. An extensive characterization of photoluminescence properties, electrophoresis mobility and size distribution of the nanocarrier demonstrating the stable complexes composed of plasmid DNA, chimeric peptide and BSA AuNcs were successfully formed through electrostatic interactions. In the hybrid complexes, chimeric peptide could effectively decrease the cytotoxicity of AuNcs as well as enhance internalization of plasmid harboring firefly luciferase gene into HEK 293 T. The designed nanocarrier could be a promising vector in gene delivery systems for improved theranostics applications. [ABSTRACT FROM AUTHOR]

Objective(s): Firefly luciferase is a monooxygenase enzyme that emits flash of light during the enzymatic reaction. Luciferase has been used in many bioanalytical fields from ATP detection methods to in vivo imaging. In recent decades, focus has been carried out on nanoparticles for their fluorescence properties. Semiconductor quantum dots have unique tunable properties that turn them promising tools in biological and biomedical researches, as nanosensors, photo-electrochemical and light-emitting devices. Carbon-based nanoparticles such as graphene quantum dots (GQDs) have useful benefits such as low toxicity, suitable luminescence and easy preparation. Materials and Methods: In ths study, recombinant p. pyralis luciferase was expressed and purified based on N-terminal His-tag and then kinetic parameters of enzyme activity such as Km and Vmax values in presence and absence of GQDs were calculated. Results: The results showed that Km for ATP andluciferin substrates in the presence of GQDs were increased. Fluorescence spectroscopy showed significant changes in protein structure or in fluorescence spectra and decrease in the activity of the luciferase in presence of GQD. Both loss of activity and increase of substrates Km showed decrease of catalytic efficiency presumably through structural alteration. Conclusion: From these data it can be concluded that the protein structure under the influence of GQD may have changed that lead to alteration of enzyme activity. [ABSTRACT FROM AUTHOR]

The pluripotency factor, OCT4 gene is a stemness marker that is involved in the tumorigenicity of different cancer types and knowing about molecular mechanisms of its regulation is crucially important. To date, a few microRNAs (miRNAs) are known to be regulators of OCT4 gene expression. Looking for the novel miRNAs which are capable of regulating OCT4 gene expression, our bioinformatics analysis introduced hsa-miR-3658 (miR-3658) as a bona fide candidate. Then, RT-qPCR results indicated that miR-3658 expression is decreased in colorectal cancer (CRC) tumor tissues, compared with normal pairs. Furthermore, RT-qPCR and western blot analysis showed that the OCT4 gene has been down-regulated following the miR-3658 overexpression. Consistently, dual-luciferase assay supported the direct interaction of miR-3658 with the 30-UTR sequence of OCT4 gene. Unlike in HCT116 cells, overexpression of miR-3658 in SW480 cells brought about growth inhibition, cell cycle arrest and reduced cell migration, detected by flow cytometry, and scratch test assay. Overall, these findings demonstrated that miR-3658 as a tumor suppressor miRNA exerts its effect against OCT4 gene expression, and it has the potential of being used as a prognostic marker and therapeutic target against colorectal cancer. [ABSTRACT FROM AUTHOR]

The effects of 17 kinds of additive mixtures have been studied on refolding and aggregation of a model protein, lysozyme. Most of the prepared mixtures were efficient in inhibiting aggregation of the protein, and, surprisingly, four novel additive mixtures, i.e., lactic acid: l‐arginine, lactic acid: l‐glutamine, choline chloride: lactic acid, and imidazolium salt: β‐cyclodextrin as well as choline chloride: urea exhibited a more remarkable efficacy in suppressing aggregation. Among these, lactic acid: l‐arginine was identified as the most efficient additive, and lactic acid: l‐glutamine and choline chloride: lactic acid were inefficient to recover the enzyme activity. In contrast, choline chloride: ethylene glycol: imidazole, choline chloride: glycerol: imidazole, imidazole: betaine: ethylene glycol were found to be less effective mixtures in preventing enzyme aggregation. Totally, it was demonstrated that the protective effects of the mixtures were improved as their concentrations increased. The improvement was more remarkable for imidazolium salt: β‐cyclodextrin and choline chloride: urea, where the denatured lysozyme was reactivated and recovered up to 85% of its initial activity by enhancing their concentrations from 1 to 5% (V/V). It is suggested that such solution additives may be further employed as artificial chaperones to assist protein folding and stability. [ABSTRACT FROM AUTHOR]

Arginine‐glycine‐aspartic acid (RGD) peptide family is known as the most prominent ligand for extracellular domain of integrin receptors. Specific expression of these receptors in various tissue of human body and tight association of their expression profile with various pathophysiological conditions made these receptors a suitable targeting candidate for several disease diagnosis and treatment as well as regeneration of various organs. For these reasons, various forms of RGD‐based integrins ligands have been greatly used in biomedical studies. Here, we summarized the last decade application progress of RGD for cancer theranostics, control of inflammation, thrombosis inhibition and critically discussed the effect of RGD peptides structure and sequence on the efficacy of gene/drug delivery systems in preclinical studies. Furthermore, we will show recent advances in application of RGD functionalized biomaterials for various tissue regenerations including cornea repair, artificial neovascularization and bone tissue regeneration. Finally, we analyzed clinically translatability of RGD peptides, considering examples of integrin ligands in clinical trials. In conclusion, prospects on using RGD peptide for precise drug delivery and biomaterial engineering are well discussed. [ABSTRACT FROM AUTHOR]

Colorectal cancer (CRC) is an increasingly common medical issue affecting millions worldwide, and contribution of the body's trace elements to CRC is arguable. The concentrations and buffered status of selenium, iron, copper, zinc, and phosphorus in blood and large intestinal tissues of CRC patients are, respectively, variable and vital for cell physiology. The aim of this study was to assess selenium, iron, copper, zinc, and phosphorus variations in blood and colorectal epithelia along with examining the expression of mismatch repair proteins in CRC patients with/without metastasis for potential diagnosis/therapy. Concentrations of selenium, iron, copper, zinc, and phosphorus in blood of healthy versus CRC patients and colorectal epithelia (adenocarcinomatous versus non-adenocarcinomatous/control) were measured in 40 CRC patients (55.87 ± 11.9 years old) with/without metastasis before surgery using ICP-OES. Mismatch repair (MMR) protein expression was analyzed through histopathological/immunohistochemistry assays, which was sparse in 5 CRC patient's colorectal tissues (12%). Compared with healthy individuals, blood and colorectal tissue's levels of phosphorus, copper, and iron were significantly higher in the CRC patients, and more pronounced in metastatic CRC patients; conversely, blood and colorectal tissue's selenium levels were significantly lower in metastatic patients. Unlike blood zinc, cancerous colorectal tissue's zinc concentration was significantly lower in CRC patients compared to healthy control cohorts. There was no significant difference on the measured elements in samples from CRC patients with MMR− compared to CRC patients with MMR+. Receiver operating characteristic analysis revealed a correlation of blood iron, zinc, copper, and phosphorus to CRC, and inappropriately low levels of blood and colorectal selenium correlated with exacerbated metastasis. Altered levels of selenium, iron, copper, zinc, and phosphorus in vivo may impact the pathogenesis and detection of CRC, and their diagnostic/therapeutic potential in CRC would be revealing. [ABSTRACT FROM AUTHOR]

The design and synthesis of novel bioisosteric analogues of triptorelin acetate containing tetrazole moiety at C‐ or N‐terminus of the peptides is described. Tetrazole acetic acid was synthesized through the reaction of an alkyl cyanoacetate and sodium azide, after that, it was coupled to the N‐terminus of triptorelin instead of pyroglutamic acid. In another approach, tetrazole acetohydrazide was prepared and conjugated to the C‐terminus of triptorelin instead of the amide bond. The synthesized peptides containing tetrazole moiety at the C‐ or N‐terminus of the peptide sequence are peptidomimetics of triptorelin acetate. The docking results of the designed derivatives showed the same interaction of triptorelin with the receptor but with a higher score.The peptide that has tetrazole moiety in its C‐terminus, restricted the testosterone level during four weeks of in vivo study and led to keep testosterone at a moderate level during the first week compared to control. [ABSTRACT FROM AUTHOR]

Aflatoxin (AF) B1 is a potent hepatotoxic, mutagenic, teratogenic mycotoxin and may cause immune suppression/dysregulation in humans and animals. Toxic effects of AFB1 on key mammalian immune cells (ie, leukocytes) needs to be mechanistically elucidated. In this study, along with the determination of AFB1's LC50 for certain leukocytes, we analyzed the effect of naturally occurring levels of AFB1 on apoptosis/necrosis of neutrophils, lymphocytes, and monocytes from healthy young humans (20- to 25-year-old male), dogs (1- to 2-year-old Persian/herd breed), and cattle (1- to 2-year-old cattle). Leukocytes were incubated for approximately 24 hours with naturally occurring levels of AFB1 (10 ng/mL). Intracellular adenosine triphosphate (ATP) depletion and caspase-3/7 activity were then determined by luciferase-dependent bioluminescence (BL). Furthermore, the necrotic leukocytes were measured using propidium iodide (PI)-related flow cytometry. A significant decrease (24%-45%, 33.2% ± 2.7%) in intracellular ATP content was observed in AFB1-treated neutrophils, lymphocytes, and monocytes in all studied mammals. Also, with such a low level (10 ng/mL) of AFB1, BL-based caspase-3/7 activity (BL intensity) in all 3 tested mammalian leukocyte lineages was noticeably increased (∼>2-fold). Flow cytometry-based PI staining (for viability assay) of the AFB1-treated leukocytes showed slightly/insignificantly more increase of necrotic (PI+) neutrophils, lymphocytes, and monocytes in human, dogs, and cattle. Even though in vitro LC50s for AFB1' (∼20,000-40,000 ng/mL) were approximately 2,000 to 4,000 times higher than background, these studies demonstrate leukocytes from human and farm/companion animals are sensitive to naturally occurring levels of AFB1. The observed in vitro ATP depletion and caspase activation in AFB1-exposed leukocytes can partially explain the underlying mechanisms of AFB1-induced immune disorders in mammals. [ABSTRACT FROM AUTHOR]

An enzyme-free aptameric nanosensor is presented for apoptosis assay. The method exploits the peroxidase-mimicking property of silver/platinum alloy nanoclusters (Ag/Pt NCs) and uses a Cyt c binding ssDNA aptamer. An extra-strand polycytosine (C14) aptamer was designed as a template for synthesis of the Ag/Pt NCs. If cell lysate or purified Cyt c is placed in a polystyrene microplate, Cyt c will bind to the surface of the wells of a microtiterplate. On addition of Apt@Ag/PtNCs, it will associate with Cyt c and then catalytically oxidize colorless tetramethylbenzidine (TMB) in the presence of H2O2 to give a blue colored oxidation product (TMBox) due to the peroxidase-mimicking property of the Ag/Pt NCs. Under optimal conditions, the absorbance of TMB at 660 nm is linearly enhanced as the concentration of Cyt c increases from 50.0 fM to 500 nM, and the detection limit is ~10 pM. The assay is simple, sensitive and cost effective in that it is enzyme-free, antibody-free and label-free. [ABSTRACT FROM AUTHOR]

The expense and time required for in vivo reproductive and developmental toxicity studies have driven the development of in vitro alternatives. Here, we used a new in vitro split luciferase‐based assay to screen a library of 177 toxicants for inhibitors of apoptosome formation. The apoptosome contains seven Apoptotic Protease‐Activating Factor‐1 (Apaf‐1) molecules and induces cell death by activating caspase‐9. Apaf‐1‐dependent caspase activation also plays an important role in CNS development and spermatogenesis. In the in vitro assay, Apaf‐1 fused to an N‐terminal fragment of luciferase binds to Apaf‐1 fused to a C‐terminal fragment of luciferase and reconstitutes luciferase activity. Our assay indicated that pentachlorophenol (PCP) inhibits apoptosome formation, and further investigation revealed that PCP binds to cytochrome c. PCP is a wood preservative that reduces male fertility by ill‐defined mechanisms. Although the data show that PCP inhibited apoptosome formation, the concentration required suggests that other mechanisms may be more important for PCP's effects on spermatogenesis. Nonetheless, the data demonstrate the utility of the new assay in identifying apoptosome inhibitors, and we suggest that the assay may be useful in screening for reproductive and developmental toxicants. [ABSTRACT FROM AUTHOR]

In recent years there has been much interest in development of multifunctional drug delivery systems. In this work, liposomes that contain doxorubicin (Dox), a potent anticancer drug, and graphene nanosheets (GNS) were prepared. The GNSs have excellent optical properties, such as photoluminescence which enables tracking of the liposomes, high absorption in ultra violet region of electromagnetic spectrum which can be exploited in photodynamic and photothermal therapy, and low toxicity to mammalian cells. Nanoliposomes were prepared using the thin film hydration method. Dox and GNSs were loaded to the liposomes during the hydration of the lipid film. Liposomes were characterized and the profile of in vitro drug release, cellular uptake, and cytotoxicity of the prepared liposomes on MCF-7 cells were determined. Despite the earlier reports, the liposomes have kept their spherical structures in the presence of GNSs. The cytotoxicity of liposomal Dox and GNSs were shown to be higher than the free forms of them. Novel nanoliposomes that contain GNSs have provided a multi-functional system with the potential of tracking, photodynamic and photothermal therapy. Further improvements of this versatile nanosystem would be promising for treatment of cancer. [ABSTRACT FROM AUTHOR]

It is known truncated Nuclear matrix protein 22 (t-NMP22) could be used a biomarker for Bladder cancer. Therefore, in this paper a highly sensitive electrochemical technique was developed based on nanostructures modified glassy carbon (GC) electrode for detection of t-NMP22. In this measurement, immunosensor was fabricated based on the electrodeposition of gold in general the upper frequency limit is determined by the solution resistance, which depends on the specific conductivity of the electrolyte and the electrode radius. To increase the sensitivity of the electrochemical system for detection of t-NMP22, the most important parameters were optimized. The fabrication steps of the immunosensor were characterized by cyclic voltammetry and electrochemical impedance spectroscopy. FFT square wave voltammetry (FFTSWV) was used for measurements at optimum condition. Moreover, the effect of important parameters such pH the FFTSWV parameters were investigated. The modified electrode was used for determination of different concentrations of t-NMP22; a linear range from 0.05 ng/mL to 30 ng/mL and a detection limit of 16.4 pg/mL were obtained. The proposed detection technique does not need a redox probe and was evaluated in urine, which showed good selectivity, high sensitivity and stability, reproducibility. [ABSTRACT FROM AUTHOR]

Abstract: Stabilization and immobilization on a proper support is essential in processing and production of enzymes. Luciferase is an unstable, thermally sensitive, and light-emitting enzyme that requires stabilization for efficiency and productivity in bio-luminescence reactions. In this work, a known and well-porous framework, MIL-53(Al), was used, for the first time, to support the immobilization of firefly luciferase. Interestingly, all the stability values were improved through the immobilization process, and the content of the loading enzyme on MIL-53(Al) was found to be significant. The results obtained indicated that the stabilization of firefly luciferase on MIL-53(Al) proceeded through the adsorption method. MIL-53(Al) was also characterized by the FT-IR, X-ray diffraction, FE-SEM, TEM, BET, and TGA techniques in order to determine the carboxylic groups and symmetric/asymmetric CO2, percentage of crystallinity and its purity, morphology, size, and shape of the MIL-53(Al) particles, and surface-to-area ratio and thermal gravimetry of support.Graphical abstract: [ABSTRACT FROM AUTHOR]