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Two-dimensional (2D) π-conjugated metal–organic frameworks (πMOFs) are a new class of designer electronic materials that are porous and tunable through the constituent organic molecules and choice of metal ions. Unlike typical MOFs, 2D πMOFs exhibit high conductivity mediated by delocalized π-electrons and have promising applications in a range of electrical devices as well as exotic physical properties. Here, we develop a growth method that generates single-crystal plates with lateral dimensions exceeding 10 μm, orders of magnitude bigger than previous methods. Synthesis of large single crystals eliminates a significant impediment to the fundamental characterization of the materials, allowing determination of the intrinsic conductivity and mobility along the 2D plane of πMOFs. A representative 2D πMOF, Ni-CAT-1, exhibits a conductivity of up to 2 S/cm, and Hall measurement reveals the origin of the high conductivity. Characterization of crystalline 2D πMOFs creates the foundation for developing electronic applications of this promising and highly diverse class of materials., A new growth method that generates the first large planar crystals of 2D conductive metal−organic frameworks enables electrical characterization along the 2D plane.

Crystalline, electrically conductive, and intrinsically porous materials are rare. Layered two-dimensional (2D) metal–organic frameworks (MOFs) break this trend. They are porous crystals that exhibit high electrical conductivity and are novel platforms for studying fundamentals of electricity and magnetism in two dimensions. Despite demonstrated applications, electrical transport in these remains poorly understood because of a lack of single crystal studies. Here, studies of single crystals of two 2D MOFs, Ni3(HITP)2 and Cu3(HHTP)2, uncover critical insights into their structure and transport. Conductivity measurements down to 0.3 K suggest metallicity for mesoscopic single crystals of Ni3(HITP)2, which contrasts with apparent activated conductivity for polycrystalline films. Microscopy studies further reveal that these MOFs are not isostructural as previously reported. Notably, single rods exhibit conductivities up to 150 S/cm, which persist even after prolonged exposure to ambient conditions. These single crystal studies confirm that 2D MOFs hold promise as molecularly tunable platforms for fundamental science and applications where porosity and conductivity are critical., A single crystal conductive metal−organic frameworks device and its metallic conduction.

Acute doses of topiramate (TPM) have been shown to reduce immobility time in the mice forced swimming test (FST) through inhibition of the nitric oxide (NO) pathway. Adenosine triphosphate–sensitive potassium (KATP) channels are known to have an active role in depression. This study investigates the potential participation of KATP channels in the antidepressant-like effect of TPM through the stimulatory effects of NO. FST and tail suspension tests (TST) were applied to adult male mice for assessment of the antidepressant-like activity of TPM. Different doses of glibenclamide and cromakalim were also applied in order to investigate the involvement of KATP channels. Fluoxetine was used as a positive control for evaluation of antidepressant-like effects. In addition, each animal’s locomotor activity was evaluated by the open-field test (OFT). TPM (30 mg/kg intraperitoneal (i.p.)) had a significant reductive effect on the immobility behavior similar to fluoxetine (20 mg/kg). Co-administration of sub-effective doses of glibenclamide (1 mg/kg i.p.) and TPM (10 mg/kg i.p.) led to significant synergistic effects in FST and TST. Additionally, the results showed that administration of the sub-effective dose of cromakalim (0.1 and 0.3 mg/kg i.p.) blocked the antidepressant-like effects of TPM (30 mg/kg i.p.) in both tests. These interventions had no impact on the locomotor movement of mice in OFT. This study shows that the antidepressant-like activity of TPM may potentially be mediated by the blocking of the KATP channels.

Exogenous melatonin application at 0, 1, 10, 100, and 1000 µM retarded cap browning of button mushrooms (Agaricus bisporus) by 78.35, 31.40, 30.91, 27.17, and 32.50 %, respectively. Mushrooms treated with 100 µM melatonin also had lower weight loss and higher firmness. During the first 5 days of storage at 4 °C, higher H2O2 accumulation may serve as a signal for promoting endogenous melatonin accumulation by triggering the expression of TDC, T5H, SNAT, and ASMT genes, beneficial for preserving membrane integrity. Besides, the higher accumulation of phenols in mushrooms treated with 100 µM melatonin may be ascribed to higher PAL and lower PPO gene expression and enzyme activity. Moreover, higher DPPH scavenging capacity in mushrooms treated with 100 µM melatonin may be ascribed to the higher accumulation of phenols and ascorbic acid.

Context: Polypropylenimine (PPI), a cationic dendrimer with defined structure and positive surface charge, is a potent non-viral vector. Dexamethasone (Dexa) conveys to the nucleus through interaction with its intracellular receptor. Objective: This study develops efficient and non-toxic gene carriers through conjugation of Dexa at various percentages (5, 10 and 20%) to the fourth and the fifth generation PPIs (PPIG4s and PPIG5s). Materials and methods: The 21-OH group of Dexa (0.536 mmol) was modified with methanesulfonyl chloride (0.644 mmol) to activate it (Dexa-mesylate), and then it was conjugated to PPIs using Traut's reagent. After dialysis (48 h) and lyophilization, the physicochemical characteristics of products (PPI-Dexa) including zeta potential, size, buffering capacity and DNA condensing capability were investigated and compared with unmodified PPIs. Moreover, the cytotoxicity and transfection activity of the Dexa-modified PPIs were assessed using Neuro2A cells. Results: Transfection of PPIG4 was close to PEI 25 kDa. Although the addition of Dexa to PPIG4s did not improve their transfection, their cytotoxicity was improved; especially in the carrier to DNA weight ratios (C/P) of one and two. The Dexa conjugation to PPIG5s enhanced their transfection at C/P ratio of one in both 5% (1.3-fold) and 10% (1.6-fold) Dexa grafting, of which the best result was observed in PPIG5-Dexa 10% at C/P ratio of one. Discussion and conclusions: The modification of PPIs with Dexa is a promising approach to improve their cytotoxicity and transfection. The higher optimization of physicochemical characteristics, the better cell transfection and toxicity will be achieved.

Molecular-scale manipulation of electronic and ionic charge accumulation in materials is the backbone of electrochemical energy storage1–4. Layered van der Waals (vdW) crystals are a diverse family of materials into which mobile ions can electrochemically intercalate into the interlamellar gaps of the host atomic lattice5,6. The structural diversity of such materials enables the interfacial properties of composites to be optimized to improve ion intercalation for energy storage and electronic devices7–12. However, the ability of heterolayers to modify intercalation reactions, and their role at the atomic level, are yet to be elucidated. Here we demonstrate the electrointercalation of lithium at the level of individual atomic interfaces of dissimilar vdW layers. Electrochemical devices based on vdW heterostructures 13 of stacked hexagonal boron nitride, graphene and molybdenum dichalcogenide (MoX2; X = S, Se) layers are constructed. We use transmission electron microscopy, in situ magnetoresistance and optical spectroscopy techniques, as well as low-temperature quantum magneto-oscillation measurements and ab initio calculations, to resolve the intermediate stages of lithium intercalation at heterointerfaces. The formation of vdW heterointerfaces between graphene and MoX2 results in a more than tenfold greater accumulation of charge in MoX2 when compared to MoX2/MoX2 homointerfaces, while enforcing a more negative intercalation potential than that of bulk MoX2 by at least 0.5 V. Beyond energy storage, our combined experimental and computational methodology for manipulating and characterizing the electrochemical behaviour of layered systems opens new pathways to control the charge density in two-dimensional electronic and optoelectronic devices.

With high potency in treatment of various diseases, gene therapy is mainly hindered by lack of safe and efficient gene delivery vectors. The current study was aimed to develop an efficient non-viral vector with adequate cytotoxicity. To this end, alkylcarboxylate chains (6C, 10C, 16C) were exploited to ameliorate the characteristics of PEI 750 kDa. Briefly, alkylcarboxylate chains with three different lengths (6C, 10C, 16C) were chemically grafted to the primary amine groups of PEI 750 kDa in three percentages (10, 50, and 100%). After evaluating the physicochemical properties of prepared vectors including surface charge, size, buffering capacity, and DNA condensing, their transfection efficiency and cytotoxicity were investigated in Neuro2A cells. The polyplexes size were 158.9–264.5 nm and their zeta potentials were 14–30 mV, while their buffering capacity and DNA condensing were not significantly decreased. The highest transfection efficiency in term of C/P ratio was observed in PEI750-10C-68%, PEI750-10C-7%, and PEI750-6C-7% at C/P ratios of 2, 4, and 6, respectively. Altogether, the decanoylcarboxylate-modified PEI with medium grafting percentages showed promising results as gene delivery vector. To sum up, the modification of high molecular weight PEIs by alkylcarboxylate chains is an efficient approach for development of more efficient non-viral vectors.

Nuclear transportation of genetic materials is a critical step in gene therapy. Human gene therapy is not routine enough in clinic because an effective and safe gene carrier does not exist yet. It is reported that glucocorticoids such as dexamethasone (Dexa) facilitate nuclear transportation of plasmid DNA or other polynucleotide molecules to the nucleus. This study is aimed to investigate the influences of Dexa on physicochemical properties, cell transfection and toxicity of polyallylamine (PAA). After activation, Dexa mesylate was conjugated to both unmodified PAA and hexyl acrylate-conjugated PAAs (PAA-6c Acr) through a one-step reaction. PAA-Dexa was purified with dialysis against distilled water and then freeze-dried. The physicochemical properties of the synthesized vectors such as buffering capacity, DNA condensing ability, size, and zeta potential were determined. The PAA 15 kDa-based polyplexes showed better cell transfection than those based on PAA65 kDa in Neuro2A cell line. To sum up, transfection activity was improved in two types of the modified vectors including PAA15-6c Acr30%-Dexa5% at lower carrier to pDNA (C/P) ratios and PAA15-6c Acr50%-Dexa10% at higher C/P ratios. Altogether, the modification of PAA and PAA-6c Acr with Dexa significantly reduced their cytotoxicity, but had not guided their cell transfection to a desired point.

Cadmium (Cd) is one of the most common environmental and occupational heavy metals with extended distribution. Exposure to Cd may be associated with several deleterious consequences on the liver, bones, kidneys, lungs, testes, brain, immunological, and cardiovascular systems. Overproduction of reactive oxygen species (ROS) as the main mechanism behind its toxicity causes oxidative stress and subsequent damages to lipids, proteins, and DNA. Therefore, antioxidants along with chelating agents have shown promising outcomes against Cd-induced toxicity. Curcumin with various beneficial effects and medical efficacy has been evaluated for its inhibitory activities against biological impairments caused by Cd. Thus, this article is intended to address the effectiveness of curcumin against toxicity following Cd entry. Curcumin can afford to attenuate lipid peroxidation, glutathione depletion, alterations in antioxidant enzyme, and so forth through scavenging and chelating activities or Nrf2/Keap1/ARE pathway induction. © 2017 BioFactors, 43(5):645-661, 2017.

Breast cancer is among the most important causes of cancer related death in women. There is a need for novel agents for targeting key signaling pathways to either improve the efficacy of the current therapy, or reduce toxicity. There is some evidence that curcumin may have antitumor activity in breast cancer. Several clinical trials have investigated its activity in patients with breast cancer, including a recent trial in breast cancer patients receiving radiotherapy, in whom it was shown that curcumin reduced the severity of radiation dermatitis, although it is associated with low bioavailability. Several approaches have been developed to increase its absorption rate (e.g., nano crystals, liposomes, polymers, and micelles) and co-delivery of curcumin with adjuvants as well as different conjugation to enhance its bioavailability. In particular, micro-emulsions is an option for transdermal curcumin delivery, which has been reported to increase its absorption. Lipid-based nano-micelles is another approach to enhance curcumin absorption via gastrointestinal tract, while polymer-based nano-formulations (e.g., poly D, L-lactic-co-glycolic [PLGA]) allows the release of curcumin at a sustained level. This review summarizes the current data of the therapeutic potential of novel formulations of curcumin with particular emphasis on recent preclinical and clinical studies in the treatment of breast cancer.

Efficient gene therapy is mainly dependent on the gene transfer capability of gene delivery vectors. Non-viral vectors have become the research interest of many researchers because these vectors are safer than viral vectors. Acquiring the advantages of both polyplexes and lipoplexes, the lipopolyplex (LPP) is a ternary nanocomplex composed of cationic liposome, polycation, and nucleic acid. Considering the polycationic component, ternary complexes (LPPs) are divided into cationic polymer-based LPPs and cationic peptide-based LPPs. Considering the capability of rational design, LPP is an interesting field of research to design a more potent nucleic acid carrier. With the promising transfection activity and safety observed in the LPPs, many researchers have formulated various types of lipids and polycations to achieve an efficient and safe carrier for gene therapy. Here we provide a review on the designed LPPs for efficient delivery of different nucleic acids such as plasmid DNA, siRNA, shRNA, and DNA vaccines.

Introduction: One of the most common complications of spinal anesthesia in elective cesarean is a headache, known commonly as post-dural-puncture headache (PDPH). Various methods are mainly recommended such as resting and the use of non-opioid analgesics, caffeine, and codeine, but none of them has been fully effective in its treatment. Hence, this study was conducted to evaluate the effect of magnesium sulfate on the prevention of post-dural-puncture headache in the elective cesarean. Method: a total of 68 patients candidate for elective cesarean and admitted to Kamali Hospital were selected using convenient sampling and they were randomly divided into two groups. One group received magnesium and other group received saline. Subjects of case group received magnesium at the dose of 50 mg / kg as bolus and the subjects of control group received normal saline at the same dose as bolus. The incidence of headache and its severity 12, 24, 36, 48 ​​, 60 and 72 hours after surgery were measured in both case and control groups. Results: The mean age of patients in the magnesium sulfate group was 27.94 years with a standard deviation of 5.18 and the mean age of patients in the normal saline group was 29.35 years with a standard deviation of 5.97. The mean body mass index (BMI) in the magnesium sulfate group was 26.34 with a standard deviation of 4.03 and the mean body mass index (BMI) in the normal saline group was 27.15 with a standard deviation of 2.47. Post-dural-puncture headache severity was lower in the case group than that in the control group at all times (P

With unique characteristics such as high surface area, capacity of various functionalization, low weight, high conductivity, thermal and chemical stability, and free radical scavenging, carbon nanomaterials (CNMs) such as carbon nanotubes (CNTs), fullerene, graphene (oxide), carbon nanohorns (CNHs), and their derivatives have increasingly been utilized in nanomedicine and biomedicine. On the one hand, owing to ever-increasing applications of CNMs in technological and industrial fields as well as presence of combustion-derived CNMs in the ambient air, the skepticism has risen over the adverse effects of CNMs on human being. The influences of CNMs on cardiovascular system and cardiovascular diseases (CVDs) such as atherosclerosis, of which consequences are ischemic heart disease and ischemic stroke, as the main causes of death, is of paramount importance. In this regard, several studies have been devoted to specify the biomedical applications and cardiovascular toxicity of CNMs. Therefore, the aim of this review is to specify the roles and applications of various CNMs in atherosclerosis, and also identify the key role playing parameters in cardiovascular toxicity of CNMs so as to be a clue for prospective deployment of CNMs.

Berberine, as a phytochemical component of some medicinal Chinese herbs (most frequently Berberis vulgaris), is an isoquinoline alkaloid with many therapeutic effects including anti-viral, anti-microbial, anti-diarrhea, anti-inflammatory and anti-tumor effects. Berberine has some significant effects on type 2 diabetes through adenosine monophosphate-activated protein kinase activation, glycolysis stimulation, and mitochondrial function inhibition which subsequently improves both lipid and glucose metabolism. Some other effects of berberine on congestive heart failure, cardiac arrhythmia and hypertension have been reported. Beside the beneficial effects of berberine, some limitations including poor aqueous solubility, slight absorption, and low bioavailability have hindered its applications. To overcome these limitations, nanotechnology has been considered as main strategy. This review describes different types of nanocarriers (polymeric based, magnetic mesoporous silica based, lipid based, dendrimer based, graphene based, silver and gold nanoparticles) have been used for encapsulation of berberine.

Solid lipid nanoparticles (SLNs), as alternative colloidal carriers, have been used for the sustained release of lipophilic drugs with poor water solubility. One of the most important parameters in the characterization of SLNs is entrapment efficiency (EE). Despite the importance of this factor in estimating the drug loading capacity, EE does not always represent the exact percentage of the entrapped drug. Several variables such as the stirring speed and duration, and concentration of surfactant, emulsifier, and drug play important roles in determining the final EE. In addition, EE is mainly affected by the type and concentration of the lipid. There are two major methods for the measurement of EE are in which the encapsulated drug in SLNs is either directly measured (direct method) or the amount of unencapsulated drug in the supernatant is measured (indirect method). Accuracy of drug analysis is the main challenge for EE calculation, and is either performed in the separated aqueous medium or the particles. In this review, we aimed to introduce the available methods for EE determination in SLNs and discuss the advantages and shortcomings of each method.

Non-viral vectors such as polymers and liposomes have been used as gene delivery systems to overcome intrinsic problems of viral vectors, but transfection efficiency of these vectors is lower than viral vectors. In the present study, we tried to design non-viral gene delivery vectors that mimic the viral vectors using the benefits of both cationic liposomes and cationic polymer vectors along with targeting glucocorticoid receptors to enhance cellular trafficking of vectors. Cationic liposomes containing DOTAP and cholesterol were prepared by thin-film hydration following extrusion method. Dexamethasone mesylate was synthesized and then conjugated to polyethylenimine through a one-step reaction. A novel gene delivery system, Lipopolyplex was developed by premixing liposome and different molecular weight of bPEI-Dexa as carriers followed by addition of plasmid at three different carrier/pDNA (C/P) weight ratios. The resulted complexes were characterized for their size, zeta potential and ability of DNA condensation. Transfection efficiency of vectors in neuro2A was determined by Luciferase reporter gene assay. Also, the toxicity of gene carriers was investigated in this cell line. Mean particle size of prepared complexes was less than 200 nm and there was no significant difference in their size by increasing the molecular weight of PEIs. All complexes had positive surface charge. Complete condensation of DNA was occurred at C/P ratio of one for all complexes. Lipopolyplexes were more efficient than polyplexes and lipoplexes alone and transfection efficiency was improved by adding dexamethasone. The complexes containing liposome, PEI 10 kDa and dexamethasone (PEI10:Lipo:Dexa(0.05)) had the highest transfection activity about 40-fold and 3.6-fold in comparison with PEI10 and PEI10:Lipo, respectively. Furthermore, the non-viral vectors described in this study showed low cytotoxicity. The results of this study confirmed that PEI in combination with liposome forms lipopolyplex with low toxicity and enhanced transfection efficiency. Moreover, using dexamethasone, in combination with lipopolyplex might be useful to increase the gene delivery potential of these lipopolyplexes.

The applications of dendrimer-based vectors seem to be promising in non-viral gene delivery because of their potential for addressing the problems with viral vectors. In this study, generation 3 poly(propyleneimine) (G3-PPI) dendrimers with 1, 4-diaminobutane as a core initiator was synthesized using a divergent growth approach. To increase the hydrophobicity and reduce toxicity, 10% of primary amines of G3-PPI dendrimers were replaced with bromoalkylcarboxylates with different chain lengths (6-bromohexanoic and 10-bromodecanoic). Then, to retain the overall buffering capacity and enhance transfection, the alkylcarboxylate–PPIs were conjugated to 10 kDa branched polyethylenimine (PEI). The results showed that the modified PPI was able to form complexes with the diameter of less than 60 nm with net-positive surface charge around 20 mV. No significant toxicity was observed in modified PPIs; however, the hexanoate conjugated PPI–PEI (PPI-HEX-10% PEI) and the decanoate conjugated PPI–PEI (PPI-DEC-10%-PEI) showed the best transfection efficiency in murine neuroblastoma (Neuro-2a) cell line, even PPI-HEX-10%-PEI showed transfection efficiency equal to standard PEI 25 kDa with reduced toxicity. This study suggested a new series of hyperbranched (PEI)–dendrimer (PPI) architectural copolymers as non-viral gene delivery vectors with high transfection efficiency and low toxicity.

The effects of gamma radiation treatment (50 and 100 Gy) on potato tubers irradiated at different days (10th, 30th and 50th) after harvest were studied during 5 months of storage at 10°C using Agria and Marfona varieties. A factorial experiment was done, based on a Randomized Complete Block Design with four replications. The 100 Gy radiation treatments on 10th and 30th days after harvest completely prevented sprouting at both varieties studied but on 50th day only Agria tubers not sprouted. This study indicated that early irradiation and absorbed radiation doses significantly decreased sprouting, percent weight loss and specific gravity of tubers. Reducing sugar content significantly increased by delay in irradiation and lower dose of radiation while non-reducing sugars did not decrease significantly by delay in irradiation and higher dose of radiation. The least increase in reducing sugars (10.2%) and most decrease in non-reducing sugar (−12.75%) were observed in tubers that irradiated on 10th day after harvest. The content of ascorbic acid was decreased by irradiation with higher dose. Although delay in irradiation caused less loss of ascorbic acid (8.5%) but showed greater metabolic changes as sprouting, weight loss, firmness, and sugars contents. Also, more increased delay in irradiation needed higher radiation doses for sprout inhibition.