A new pre-concentration procedure based on poly(styrene-co-maleamide and imide) copolymers modified with 2-hydrazinobenzothiazole prior to spectrophotometric monitoring of inorganic as (as As(III)) in edible vegetable oils.

This study describes the development of 2-hydrazinobenzothiazole modified-amide/imide co-polymers for the extraction/pre-concentration of trace As(III), from edible vegetable oils. Their characterization was realized by help of instrumental techniques. The method is based on pH-dependent complexation between As(III) and co-polymeric chelators in presence of 35-fold excess As(V), their selective extraction into the mixed micellar phase, and detected at pH 2.0 and 6.0 by UV-vis spectrophotometer. The variables affecting extraction efficiency were optimized. From pre-concentration of 20-mL sample, the good linear relationships were obtained in range of 1-40 and 3-75 µg/L with DLs of 0.32 and 1.00 µg/L. The accuracy was verified by analysis of a certified sample without and with spiking. The method was applied into the analysis of iAs levels of samples. The results show that the functional co-polymers are efficient chelators, and exhibit great potential for the selective extraction of As(III) from edible vegetable oils.

The therapeutic effect of ALT-711 on erectile function in rats treated with high-level AGEs (advanced glycation end products) containing diet.

To investigate, if advanced glycation end products (AGEs) are involved in erectile dysfunction (ED) and also ALT-711, a cross-link breaker of AGEs, has the therapeutic potential against the development of ED in rats treated with high concentrated AGEs including food. For this purpose, 30 male Harlan Spraque-Dawley rats randomly were divided into three groups; (1) control rats treated with regular diet, (2) rats treated with high-level of AGE specific diet for 6 months, and (3) rats having AGE-diet treated with ALT-711 for the final 3 months of 6 months of AGE-diet period. Erectile response to cavernosal nerve stimulation (CNS), protein expression of neuronal nitric oxide synthase (nNOS) and levels of AGEs, Malondialdehyde (MDA), cyclic guanosine monophosphate (cGMP) were determined in penile tissues. Erectile responses to CNS and penile nNOS and cGMP content were significantly reduced, while AGEs and MDA were elevated in penises of Group-2. Treatment with ALT-711 reversed ED and depletion of both nNOS and cGMP. Additionally, ALT-711 treatment reduced penile tissue AGEs and MDA expression. In present study: rats without any co-morbidity such as diabetes mellitus (DM) and chronic renal failure (CRF) were treated with high-level AGEs containing food. Our results suggest that ALT-711 may be an interesting and promising approach in the treatment of AGEs-related ED.

Management of a laterally luxated upper incisor caused by the hit of a rifle stock.

Lateral luxation is the displacement of the tooth in a direction other than axial, which is accompanied by comminution or fracture of the alveolar socket. Lateral luxation is one of the most prevalent dental injuries among the general population, resulting in up to 27% of all dental wounds. All physical activities have an associated risk of orofacial injuries due to falls, collisions, and contact with hard surfaces. Just like any other training activities, military training exercises present a significant risk of dental traumas, which comprise 2% to 8% of all military dental emergencies. The aim of this report was to present a case of a dental lateral luxation caused by the hit of a rifle stock during close combat training. The tooth was extruded from its bony lock, temporarily filled with a calcium hydroxide-based paste, replaced into its original anatomic position, and secured with Ivy loop wirings. The permanent endodontic treatment was performed 4 weeks after repositioning. At the end of the 8-months follow-up, the tooth was asymptomatic and any pathological alterations were absent.

Application of a novel poly(SMAm)-Tris-Fe3O4 nanocomposite for selective extraction and enrichment of Cu(I) /Cu(II) from beer, soft drinks and wine samples, and speciation analysis by micro-volume UV-Vis spectrophotometry.

In this study, a novel functional nanocomposite was synthesized, characterized and selectively used in pH-controlled separation, pre-concentration and speciation analysis of Cu(I) and Cu(II) from sample matrices where extraction is assisted, facilitated and greatly enhanced by ultrasound energy. The hydrophilic composite material functionalized with tris(2-hydroxymethyl)aminomethane (Tris) and Fe3O4 NPs was characterized in detail by ATR-FT-IR, 1H NMR, XRD, EDX peaks and SEM images. After optimization of the main variables influencing extraction efficiency such as pH, volumes of buffer, modified copolymer in acetone, CTAB and Triton X-114 at fixed concentrations including sonication conditions, the Cu(I) and Cu(II) were monitored against a blank at 347 nm by micro-volume UV-vis spectrophotometer. A good linearity was obtained in the range of 2-140 and 5-150 µg L-1 for Cu(II) and Cu(I) with r2 ≥ 0.993. The limits of detection (LODs) of 0.66 and 1.60 µg L-1 for each analyte, were obtained from a pre-concentration of 70-fold. After validation, the method was applied to speciation of Cu(I), Cu(II), and total Cu in the pre-treated and diluted beverage samples before and after pre-oxidation of Cu(I) to Cu(II) due to be more sensitive of extraction process to Cu(II) at pH 6.0. The results were also compared with those obtained by FAAS analysis to ensure the reliability of the results. It was observed that there was a statistically good agreement between the results of both methods.

Use of 2-Hydrazinobenzothiazole-Modified Copolymer(s) as Potential Chelating Agent for Sensitive and Selective Determination of Low Levels of Mercury in Seafood by Ultrasound-Assisted Cloud-Point Extraction Combined with Spectrophotometry.

In this study, a new method was developed for the pre-concentration of trace mercury from seafood samples prior to analysis by spectrophotometry. The method is based on the complexation between 2-hydrazinobenzothiazole (2-HBT)-modified copolymer(s) and Hg(II) in the presence of an ionic surfactant, cetyltrimethylammonium bromide (CTAB), as sensitivity enhancer at pH 4.5 and the extraction of the complex into the surfactant-rich phase of polyethylene glycol tert-octylphenyl ether (Triton X-114) as the extractant. The variables affecting extraction efficiency were evaluated and optimized. Due to the observation that the modified copolymers are 2.5-fold more sensitive and selective to the Hg2+ ions than the CH3Hg+, the amounts of free Hg2+ and total Hg were determined at 325 nm by spectrophotometric detection of free Hg2+ and total Hg in the pre-treated and extracted fish samples using dilute acid mixture containing Triton X-114 and K2Cr2O7, before and after oxidation of CH3Hg+ to Hg2+ with mixture of KBr and KBrO3 in the acidic media. The amount of CH3Hg+ was calculated from the difference between total Hg and free Hg2+ amounts. The accuracy was tested by analysis of two certified samples. The results were statistically in good agreement with the certified values, and the precision was lower than 6.4%. The limits of detection were 1.40 (1.58) and 1.91 (2.11) µg L-1 for Hg2+ from the two calibration solutions spiked before the pre-treatment, respectively. It has been observed that there is no significant matrix effect by comparison of slopes of the calibration curves. The method was applied to seafood samples for speciation analysis of free Hg2+ and CH3Hg+. In terms of speciation, while total Hg is detected in the range of 12.6-143.8 µg kg-1, the distribution of mercury in seafood was in the range of 7.4-53.3 µg kg-1 for CH3Hg+ and in 8.3-90.5 µg kg-1 for free Hg2+.

Investigation of separation and identification possibilities of some metal-DEDTC complexes by sequential TLC-IR system.

The separation and identification possibilities of some metal-diethyldithiocarbamate (DEDTC) complexes are investigated by thin-layer chromatography-IR sequential system. DEDTC complexes of metal cations are prepared in a predetermined optimum pH or pH range. Optimum separation conditions of these complexes and the reproducibilities of their retention factor (Rf) values are investigated on a series of precoated or laboratory-made TLC plates. Rf values are determined using the one-dimensional ascending technique. The precision of the procedures is determined for five replicates in terms of standard deviation. Detection limits are also determined for each of the metal complexes. The IR spectra are scanned and interpreted for their precise identifications after preconcentration with a wick-stick procedure for the complexes, giving the overlapped Rf values. The complexes could be identified by the aid of IR absorption bands. It has been determined that these IR absorption bands can also be used as reference spectral bands in possible quantitative studies. It is concluded that an efficient and successful qualitative analysis is possible for incompletely-separated complex compounds using an IR spectrophotometer as the TLC detector.