Effects of Fe2+ Nanoparticles on Pain Responses and Neural Oscillation Following Chronic Neuropathic Pain in Rats.

Neuropathic pain, a chronic pain condition caused by nerve damage either of the peripheral or central nervous system, responds poorly to current drug treatments. The present study aimed to investigate the analgesic and anxiolytic effect of Fe2+ nanoparticles on chronic constriction injury of sciatic nerve (CCI)-induced neuropathic pain in rats. We also assessed the effects of Fe2+ nanoparticles on brain rhythmical oscillation in rats with neuropathic pain. The CCI model was induced by four loose ligations of the left sciatic nerve. Male Wistar rats were divided into four groups: control, sham, CCI, and CCI+Fe2+ nanoparticle (1 mg/kg). The Fe2+ nanoparticle was administered by gavage on the day of CCI surgery (day 0) and daily (once a day) for 21 consecutive days after CCI surgery. Behavioral studies were conducted on days -1, 3, 7, 14, and 21 after CCI. An acetone test and elevated plus maze were performed to evaluate cold allodynia and induced anxiety-like responses, respectively. A field test was conducted to evaluate innate anxiety-like behaviors. In addition, an electrophysiological study was carried out on day 21 after CCI to assess the effects of drugs on brain wave power. Application of Fe2+ significantly reduced cold allodynia in all tested days after CCI, compared to the CCI group. The obtained data demonstrated that Fe2+ nanoparticle gavage caused analgesic and anxiolytic effects on all experimental days after CCI, compared to the CCI group. The CCI surgery significantly disturbed theta, alpha, and beta power in the brain. The application of Fe2+ nanoparticles could not significantly change brain wave power. It is suggested that Fe2+ nanoparticle has analgesic and anxiolytic effects during chronic neuropathic pain in rats. Furthermore, the CCI surgery effectively disturbed brain theta, alpha, and beta power. Nonetheless, the application of Fe2+ nanoparticles could not change deregulated brain oscillation in rats.

Essential oil composition of Eucalyptus procera Dehnh. leaves from central Iran.

The chemical composition of the essential oil of leaves of Eucalyptus procera Dehnh., cultivated in central Iran, was obtained by hydrodistillation and analysed by GC-MS. Forty-five constituents representing 99.6% of the total oil were identified. The main constituents of the oil were found to be 1,8-cineole (35.9%), α-pinene (25.6%) and viridiflorol (7.7%). Other representative compounds were identified as α-terpineol (3.6%), aromadendrene (3.5%) and trans-pinocarveol (3.0%).

Chemical composition and antioxidant activity of the essential oil and various extracts of Haplophyllum robustum Bge.

This study was designed to examine the chemical composition and in vitro antioxidant activity of the essential oil and various extracts of Haplophyllum robustum. GC-MS analysis of the oil resulted in the identification of 30 compounds, representing 99.2% of the oil; 1,8-cineole (38.1%), myrcene (10.7%), α-pinene (8.5%), 4-terpineol (7.0%) and sabinene (6.1%) were the main components. The antioxidant potential of the oil and extracts was evaluated using three separate methods: inhibition of the free radical 2,2-diphenyl-1-picrylhydrazyl (DPPH), ß-carotene-linoleic acid assay and reducing power systems. The essential oil of the plant was able to reduce the stable free radical DPPH with an IC(50) of 72.0 ± 1.2 µg mL(-1) (the IC(50) for ascorbic acid was determined as 5.8 ± 0.4 µg mL(-1)). The essential oil also showed strong reducing power. The level of total phenolics was highest in the essential oil (179.5 ± 2.1 µg mg(-1)).

Determination of the chemical composition and in vitro antioxidant activities of essential oil and methanol extracts of Echinophora platyloba DC.

This study was designed to examine the chemical composition and in vitro antioxidant activity of essential oil and methanol extracts of Echinophora platyloba from Iran. Gas chromatography (GC) and GC/MS (mass spectrometry; MS) analysis of the essential oil resulted in the identification of 29 compounds, which comprised 97.4% of the oil. The main constituents were found to be: (Z)-ß-ocimene (26.7%), Δ-3-carene (16.2%) and limonene (6.6%). Antioxidant activities of the essential oil and the methanolic extracts from E. platyloba were evaluated using three different test systems, namely 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging, ß-carotene-linoleic acid bleaching and reducing power assays. In the DPPH system, the highest radical-scavenging activity was shown by the polar sub-fraction of methanol extract (71.2 ± 1.11 µg mL(-1)). Also in the second case, the relative inhibition capacity (%) of the essential oil (68.0 ± 1.14%) was found to be the stronger one. In addition, the amounts of total phenol components in the polar sub-fractions of methanolic extract (67.5 ± 0.48 µg mg(-1)), nonpolar sub-fractions of methanol extract (35.3 ± 0.12) and the oil (83.3 ± 0.24 µg mg(-1)) were determined.

Study binding of Al-curcumin complex to ds-DNA, monitoring by multispectroscopic and voltammetric techniques.

In this work a complex of Al3+ with curcumin ([Al(curcumin) (EtOH)2](NO3)2) was synthesized and characterized by UV-vis, FT-IR, elemental analysis and spectrophotometric titration techniques. The mole ratio plot revealed a 1:1 complex between Al3+ and curcumin in solution. For binding studies of this complex to calf thymus-DNA various methods such as: UV-vis, fluorescence, circular dichroism (CD), FT-IR spectroscopy and cyclic voltammetry were used. The intrinsic binding constant of ACC with DNA at 25°C was calculated by UV-vis and cyclic voltammetry as 2.1×10(4) and 2.6×10(4), respectively. The thermodynamic studies showed that the reaction is enthalpy and entropy favored. The CD results showed that only the Δ-ACC interacts with DNA and the Δ-ACC form has not any tendency to interact with DNA, also the pure curcumin has not any stereoselective interaction with CT-DNA. Fluorimetric studies showed that fluorescence enhancement was initiated by a static process in the ground state. The cyclic voltammetry showed that ACC interact with DNA with a binding site size of 2. From the FT-IR we concluded that the Δ-ACC interacts with DNA via partial electrostatic and minor groove binding. In comparison with previous works it was concluded that curcumin significantly reduced the affinity of Al3+ to the DNA.

The experimental and theoretical QM/MM study of interaction of chloridazon herbicide with ds-DNA.

We report a multispectroscopic, voltammetric and theoretical hybrid of QM/MM study of the interaction between double-stranded DNA containing both adenine-thymine and guanine-cytosine alternating sequences and chloridazon (CHL) herbicide. The electrochemical behavior of CHL was studied by cyclic voltammetry on HMDE, and the interaction of ds-DNA with CHL was investigated by both cathodic differential pulse voltammetry (CDPV) at a hanging mercury drop electrode (HMDE) and anodic differential pulse voltammetry (ADPV) at a glassy carbon electrode (GCE). The constant bonding of CHL-DNA complex that was obtained by UV/vis, CDPV and ADPV was 2.1×10(4), 5.1×10(4) and 2.6×10(4), respectively. The competition fluorescence studies revealed that the CHL quenches the fluorescence of DNA-ethidium bromide complex significantly and the apparent Stern-Volmer quenching constant has been estimated to be 1.71×10(4). Thermal denaturation study of DNA with CHL revealed the ΔTm of 8.0±0.2°C. Thermodynamic parameters, i.e., enthalpy (ΔH), entropy (ΔS°), and Gibbs free energy (ΔG) were 98.45 kJ mol(-1), 406.3 J mol(-1) and -22.627 kJ mol(-1), respectively. The ONIOM, based on the hybridization of QM/MM (DFT, 6.31++G(d,p)/UFF) methodology, was also performed using Gaussian 2003 package. The results revealed that the interaction is base sequence dependent, and the CHL has more interaction with ds-DNA via the GC base sequence. The results revealed that CHL may have an interaction with ds-DNA via the intercalation mode.

Effect of nitrate content on thermal decomposition of nitrocellulose.

Data on the thermal stability of energetic materials such as nitrocellulose was required in order to obtain safety information for handling, storage and use. In the present study, the thermal stability of four nitrocellulose samples containing various amount of nitrate groups was determined by differential scanning calorimetery (DSC) and simultaneous thermogravimetery-differential thermal analysis (TG-DTA) techniques. The results of TG analysis revealed that the main thermal degradation for the nitrocellulose occurs in the temperature ranges of 192-209 degrees C. On the other hand, the TG-DTA analysis of compounds indicates that nitrate content of nitrocellulose could has affect on its thermal stability and its decomposition temperature decrease by increasing its nitrogen percent. The influence of the heating rate (5, 10, 15 and 20 degrees C/min) on the DSC behaviour of the nitrocellulose was verified. The results showed that, as the heating rate was increased, decomposition temperature of the compound was increased. Also, the kinetic parameters such as activation energy and frequency factor for the compound was obtained from the DSC data by non-isothermal methods proposed by ASTM E696 and Ozawa.

Highly selective and sensitive copper membrane electrode based on a new synthesized Schiff base.

Bis(2-hydroxyacetophenone)butane-2,3-dihydrazone (BHAB) was used as new N-N Schiffs base which plays the role of an excellent ion carrier in the construction of a Cu(II) membrane sensor. The best performance was obtained with a membrane composition of 30% poly(vinyl chloride), 55% o-nitrophenyloctyl ether (NPOE), 7% BHAB and 8% oleic acid (OA). This sensor shows very good selectivity and sensitivity towards copper ion over a wide variety of cations, including alkali, alkaline earth, transition and heavy metal ions. The effect of membrane composition and pH and influence of additive anionic on the response properties of electrode were investigated. The electrode exhibits a Nernstian behavior (with slope of 29.6mV per decade) over a very wide concentration range (5.0x10(-8) to 1.0x10(-2)molL(-1)) with a detection limit of 3.0x10(-8)molL(-1) (2.56ngmL(-1)). It shows relatively fast response time, in whole concentration range (<15s), and can be used for at least 12 weeks in the pH range of 2.8-5.8. The proposed sensor was successfully used to determination of copper in different water samples and as indicator electrode in potentiometric titration of copper ion with EDTA.