Selective and sensitive electrochemical sensors based on an ion imprinting polymer and graphene oxide for the detection of ultra-trace Cd(ii) in biological samples.

New selective and sensitive electrochemical sensors were designed based on the deposition of a promising ion imprinted polymer (IIP) on the surface of glassy carbon electrode (GCE) for the detection and monitoring of Cd(ii) in different real samples. Herein, a highly selective Cd-imprinted polymer was successfully synthesized using a novel heterocyclic compound based on the benzo[f]chromene scaffold that acted as a complexing agent and a functional monomer in the presence of azobisisobutyronitrile (initiator) and ethylene glycol dimethacrylate (cross-linker). The characterization of the synthesized chelating agent and IIP was performed using FT-IR, SEM, 1H-NMR, EIMS, and EDX analyses. After that, the voltammetric sensor was manufactured by introducing graphene oxide (GO) on the surface of GCE; then, the IIP was grown by a drop coating technique. The electrochemical characterization of the voltammetric sensor (IIP/GO@GCE) was performed by CV and EIS. For comparison, the potentiometric sensor was also prepared by embedding IIP in plasticized polyvinyl chloride and depositing it as one layer on the GCE surface. Anodic stripping voltammetry was used to construct the calibration graph; the IIP/GO@GCE exhibited a wider detection range (4.2 × 10-12-5.6 × 10-3 mol L-1) and extremely low detection limit (7 × 10-14 mol L-1) for Cd(ii). Meanwhile, the potentiometric sensor showed a linear calibration curve for Cd(ii) over a concentration range from 7.3 × 10-8 mol L-1 to 2.4 × 10-3 mol L-1 with a detection limit of 6.3 × 10-10 mol L-1. Furthermore, both sensors offered outstanding selectivity for Cd(ii) over a wide assortment of other common ions, high reproducibility, and excellent stability.

Bulk liquid pertraction of NaCl from aqueous solution using carrier-mediated transport.

In the present work, removal of NaCl using the bulk liquid membrane (BLM) technique has been investigated, using a simple apparatus for conducting the experiments. Variables investigated were volume ratio of donor phase (DP) to receptor phase (RP), presence of sequestering agent (SA) in RP, type of organic liquid membrane (LM), quantity of mobile carrier (MC) in the LM. Stirring speed and volume of LM were kept constant at 100 rpm and 130 ml, respectively. The mass transfer of NaCl was analysed based on kinetic laws of two consecutive irreversible first-order reactions, and kinetic parameters (k1d, k2m, k2r, , tmax, , and ) for the transport of NaCl were investigated. The values obtained demonstrate that the process is diffusionally controlled. Results indicate that the membrane entrance and exit rate constants (k1, k2) increase with decreasing DP:RP ratio and with decrease in quantity of MC, and quantity of SA, and the presence of dichloroethane (DCE) is preferred to chloroform (CF) as LM.

Green synthesis of silver nanoparticles and their application to cotton fabrics.

Herein we present a green synthesis of silver nanoparticles (AgNPs) under the reducing action of sugar and the stabilizing action of polyethylene glycol (PEG). Factors affecting the synthesis notably molecular weight of PEG and concentrations of both sugar and silver nitrate were examined for the sake of optimization. Thus obtained AgNPs were characterized, by ultraviolet-visible (UV-vis) spectra for estimation of AgNPs formation and, Transmission electron microscopy (TEM) for determination of size and shape. AgNPs were applied with 1,2,3,4-butane tetracarboxylic acid (BTCA) and sodium hypophosphite (SHP) as a catalyst to cotton fabric. Application was performed according to the conventional pad-dry-cure technique. The treated fabrics were evaluated via monitoring morphological changes of the fibers using scanning electron microscopy (SEM), tensile strength and crease recovery angles in addition to bioassay of antimicrobial activity of the treated fabrics. Research output disclosed that PEG having molecular weight 2000 is the best among the other PEG used.

Eco-friendly finishing agent for cotton fabrics to improve flame retardant and antibacterial properties.

This research work deals with flame retardant and antibacterial finishing agent for cellulosic fabrics using TiO2 nanoparticles and chitosan phosphate. TiO2 nanoparticles were prepared by sol-gel method using titanium tetraisopropoxide. The size of TiO2 nanoparticles was characterized using transmission electron microscope (TEM). The application of nano TiO2 onto cellulosic fabrics (cotton 100%) was achieved in presence of polycarboxylic acid [1,2,3,4-butane tetracarboxylic acid (BTCA)] with sodium hypophosphite (SHP) as catalyst and chitosan phosphate through conventional pad-dry-cure method. The effect of the finishing on the physical properties, flammability and antibacterial properties of cross-linked fabrics are investigated. Thermal gravimetric analysis (TGA) was employed to investigate the thermal decomposition behaviour of the treated samples. Limited oxygen indexes (LOI) of the treated cotton fabrics were investigated. The treated cotton fabric also reveals excellent antibacterial properties.

Development of improved nanosilver-based antibacterial textiles via synthesis of versatile chemically modified cotton fabrics.

Cationization of cotton fabric form was effected by reacting the cellulose with 3-chloro-2 hydroxypropyl trimethyl ammonium chloride in presence of sodium hydroxide as per the pad dry cure method. Thus obtained cationized cotton cellulose was reacted with a reactive copolymer, namely, reactive ß-cyclodextrin grafted with polyacrylic acid (MCT-ßCD-g-PAA).Bridging of another copolymer, namely, ß-cyclodextrin grafted with polyacrylic acid (ßCD-g-PAA) to the cationized fabric using epichlorohydrin crosslinker was also performed. Inclusion of Ag nanoparticles in these three cotton substrates via treatment of the latter with colloid of Ag nanoparticles or through in situ formation of the former was exercised. Characterization of cotton fabric before and after being chemically modified was carried out using FTIR, XRD and SEM. Bacterial examination of the cationized cotton containing either (MCT-ßCD-g-PAA) or (ßCD-g-PAA) incorporated with Ag nanoparticles showed these substrates function against G+ve and G-ve bacteria. Ability of (MCT-ßCD-g-PAA) modified cotton to include hydrophobic molecules was examined.

Predictors of pharmacological treatment outcomes with atomoxetine or methylphenidate in patients with attention-deficit/hyperactivity disorder from China, Egypt, Lebanon, Russian Federation, Taiwan, and United Arab Emirates.

BACKGROUND: The reduced availability of data from non-Western countries limits our ability to understand attention-deficit/hyperactivity disorder (ADHD) treatment outcomes, specifically, adherence and persistence of ADHD in children and adolescents. This analysis assessed predictors of treatment outcomes in a non-Western cohort of patients with ADHD treated with atomoxetine or methylphenidate. METHODS: Data from a 12-month, prospective, observational study in outpatients aged 6-17 years treated with atomoxetine (N = 234) or methylphenidate (N = 221) were analysed post hoc to determine potential predictors of treatment outcomes. Participating countries included the Russian Federation, China, Taiwan, Egypt, United Arab Emirates and Lebanon. Factors associated with remission were analysed with stepwise multiple logistic regression and classification and regression trees (CART). Cox proportional hazards models with propensity score adjustment assessed differences in atomoxetine persistence among initial-dose cohorts. RESULTS: In patients treated with atomoxetine who had available dosing information (N = 134), Cox proportional hazards revealed lower (< 0.5 mg/kg) initial dose was significantly associated with shorter medication persistence (p < 0.01). multiple logistic regression analysis revealed greater rates of remission for atomoxetine-treated patients were associated with age (older), country (United Arab Emirates) and gender (female) (all p < 0.05). CART analysis confirmed older age and lack of specific phobias were associated with greater remission rates. For methylphenidate, greater baseline weight (highly correlated with the age factor found for atomoxetine) and prior atomoxetine use were associated with greater remission rates. CONCLUSIONS: These findings may help clinicians assess factors upon initiation of ADHD treatment to improve course prediction, proper dosing and treatment adherence and persistence. TRIAL REGISTRATION: Observational study, therefore no registration.

In situ formation of silver nanoparticles for multifunctional cotton containing cyclodextrin.

This research presents new approach for functionalization of cotton fabrics against antibacterial. It comprises: (a) synthesis and characterization of two polymeric products that can referred to as reactive copolymer (monochlorotriazinyl-ß-cyclodextrin grafted with acrylic acid AA, MCT-ßCD-g-PAA) and normal copolymer (ß-cyclodextrin grafted with acrylic acid AA, ßCD-g-PAA), (b) reacting cotton with the reactive copolymer (c) treatment of the chemically modified cotton so-obtained with silver nitrate, (d) in situ reduction of silver ions using either the copolymer (ßCD-g-PAA) or a conventional reducing agent, namely, sodium borohydride, and (e) monitoring the antibacterial activity and resilience properties of the modified cotton fabrics. FTIR, SEM, and X-ray diffraction were employed to prove the structure of the synthesized polymeric products as well as micro structural changes in cotton cellulose as a result of the aforementioned treatments. The finished fabrics displayed superior antibacterial activity along with good fabric stabilization as indeed by fabric resilience.

Role of mast cells and T-lymphocytes in pemphigus vulgaris: significance of CD44 and the c-kit gene product (CD117).

Molecular mechanisms underlying the pathophysiology of pemphigus vulgaris are still not clear. We aimed to determine the significance of detecting expression of some antigens that might be pivotal to the process, namely CD44 and CD117, in patients with active pemphigus vulgaris. Seventeen patients with active pemphigus vulgaris and 19 normal healthy controls were included in the study. The immunohistochemical results showed prominent expression of CD44 in 13 of the patients and CD117 in 9 of the patients with new blister formation. CD44 percentage values in peripheral T-lymphocytes were significantly higher in patients than controls, as detected by flow cytometry. In addition, there was a significant increase in a soluble form of c-kit in sera of patients with active pemphigus vulgaris compared to controls.

Serum interleukins and urinary microglobulin in children with idiopathic nephrotic syndrome.

We studied 60 children affected with idiopathic nephrotic syndrome (INS) plus 20 age and sex matched controls. The children with INS were divided into 3 groups of 20: first presentation, remission and relapse. A complete blood picture and complete urinalysis were done. Serum interleukin (IL)-1beta, IL-6, tumour necrosis factor (TNF) and quantitative urinary beta-2-microglobulin (beta-2-m) excretion were estimated. IL-1beta and IL-6 were significantly higher in the study groups, the first presentation and relapse groups having the highest concentrations. Serum TNF concentration and urinary beta-2-m excretion were significantly higher in the first presentation and relapse groups. Serum IL-1beta, IL-6 and TNF concentrations were able to select positively (100%) the first presentation and relapse groups, while these plus urinary beta-2-m excretion selected negatively (100%) the control group.

Role of mast cells and T-lymphocytes in pemphigus vulgaris: significance of CD44 and the c-kit gene product [CD117]

Molecular mechanisms underlying the pathophysiology of pemphigus vulgaris are still not clear. We aimed to determine the significance of detecting expression of some antigens that might be pivotal to the process, namely CD44 and CD117, in patients with active pemphigus vulgaris. Seventeen patients with active pemphigus vulgaris and 19 normal healthy controls were included in the study. The immunohistochemical results showed prominent expression of CD44 in 13 of the patients and CD117 in 9 of the patients with new blister formation. CD44 percentage values in peripheral T-lymphocytes were significantly higher in patients than controls, as detected by flow cytometry. In addition, there was a significant increase in a soluble form of c-kit in sera of patients with active pemphigus vulgaris compared to controls

Serum interleukins and urinary microglobulin in children with idiopathic nephrotic syndrome

We studied 60 children affected with idiopathic nephrotic syndrome [INS] plus 20 age and sex matched controls. The children with INS were divided into 3 groups of 20: first presentation, remission and relapse. A complete blood picture and complete urinalysis were done. Serum interleukin [IL]-1beta, IL-6, tumour necrosis factor [TNF] and quantitative urinary beta-2-microglobulin [beta-2-m] excretion were estimated. IL-1beta and IL-6 were significantly higher in the study groups, the first presentation and relapse groups having the highest concentrations. Serum TNF concentration and urinary beta-2-m excretion were significantly higher in the first presentation and relapse groups. Serum IL-1beta, IL-6 and TNF concentrations were able to select positively [100%] the first presentation and relapse groups, while these plus urinary beta-2-m excretion selected negatively [100%] the control group

The prevalence of portal hypertensive gastropathy and duodenopathy in some Egyptian cirrhotic patients.

Portal hypertensive gastropathy (PHG) and duodenopathy (PHD) are frequent in patients with cirrhosis, both are a dynamic condition that can progress from mild to severe and vice versa or even disappear completely. This study included 300 individuals classified into three groups. G I included 116 patients with mixed liver pathology (post-viral cirrhosis and post-Bilharzial fibrosis). G II included 84 patients with pure post hepatitic viral cirrhosis. Hundred healthy individual of comparable age and sex serving as control group. Upper endoscopic examination was done for all groups; gastric varices, gastric congestion and duodenal congestion were detected in 12%, 19.5% and 14.5%, respectively in Gs I & II with statistically significant difference when they were compared to controls (P- < 0.01). In conclusion, high prevalence of PHG and PHD in cirrhotic patients was either due to post-viral cirrhosis or mixed pathology.

Effect of intravenous contrast for left ventricular opacification and border definition on sensitivity and specificity of dobutamine stress echocardiography compared with coronary angiography in technically difficult patients.

BACKGROUND: The study evaluates whether Optison used during dobutamine stress echocardiography (DSE) will improve endocardial border definition and whether this will translate to an improvement in sensitivity and specificity of the test in patients with poor echocardiographic windows. DSE is extremely valuable in the workup of patients with coronary artery disease. The test is limited in patients with suboptimal endocardial border visualization. Frequent studies have demonstrated improved endocardial border visualization with intravenous contrast agents at rest. METHODS AND RESULTS: We studied 229 patients: 112 had good rest echocardiography with no contrast and 117 had poor rest echocardiography with Optison injection during DSE. Percentage of endocardial border visualization, wall thickening, sensitivity, and specificity were compared in both groups, as was interobserver variability. Both groups were matched with respect to age, percentage of previous myocardial infarctions, resting wall motion abnormality, percentage of coronary stenosis, and number of diseased coronary arteries. Optison significantly improved endocardial border visualization, especially at peak stress. The ability to measure wall thickening was significantly higher in the contrast DSE group with suboptimal images versus the noncontrast group with optimal images (89% ability to measure wall thickening vs 71%, P =.01). This resulted in a comparable sensitivity (79% vs 71%, P = not significant [NS]), specificity (76% vs 82%, P = NS), and diagnostic accuracy (80% vs 76%, P = NS). Agreement on test interpretation was higher among 3 observers in contrast DSE versus noncontrast DSE groups (79% vs 69%, P =.01). CONCLUSIONS: In patients with poor echocardiographic windows, the use of Optison during DSE improves endocardial border visualization, which translates to a comparable sensitivity and specificity to noncontrast DSE tests in patients with good echocardiographic windows.

Comparison of relative coronary Doppler flow velocity reserve to stress myocardial perfusion imaging in patients with coronary artery disease.

To compare relative coronary artery vasodilator reserve (rCVR = CVRtarget/CVRreference) to myocardial perfusion stress imaging, 48 patients with coronary artery stenoses (61% +/- 16%; mean, +/- SD; range, 30%-91%) had measurements of target and reference vessel CVR (Doppler-tipped guidewire). rCVR was computed and compared to stress 201thallium or (99m)technetium-sestamibi myocardial tomography. Compared to 24 patients with negative stress imaging studies, 24 patients with positive stress studies had angiographically more severe stenoses (74% +/- 13% vs. 44% +/- 24%; P = 0.0005) with lower CVR(target) (1.68 +/- 0.55 vs. 2.46 +/- 0.74; P = 0.002) and lower rCVR (0.72 +/- 0.22 vs. 1.0 +/- 0.26; P < 0.003). Based on receiver-operator characteristic (ROC) cut points (CVR > 1.9; rCVR > 0.75), compared to CVR, rCVR had similar agreement (Kappa 0.54 vs. 0.50), sensitivity (63% vs. 71%), specificity (88% vs. 83%), and positive predictive value (83% vs. 81%) with myocardial perfusion tomography. A concordant CVRtarget/rCVR only slightly increased sensitivity, specificity, and positive predictive values (77%, 90%, and 87%, respectively). Although rCVR, like CVR, correlates with stress myocardial perfusion imaging results, rCVR did not have significant incremental prognostic value over CVR alone for myocardial perfusion imaging. However, rCVR does provide additional information regarding the status of the microcirculation in patients with coronary artery disease and complements the CVR for lesion assessment.

Randomized comparison of coronary angiography using 4F catheters: 4F manual versus "Acisted" power injection technique.

Compared with 6F catheters, diagnostic coronary angiographic and ventriculographic images with 4F catheters can be obtained with equivalent results using less radiographic contrast volume. Whether 4F coronary angiography would be superior using a power-assisted, operator-controlled technique compared with manual technique is unknown. To determine whether 4F coronary angiography using operator-controlled power injection (Acist, Minneapolis, MN) was equivalent or superior to the 4F manual technique, 96 unselected patients undergoing transfemoral coronary angiography were randomized to 4F catheter using a power injection or manual technique. Procedural characteristics and angiographic quality scores were analyzed. Comparing the 4F manual with the 4F power-injection technique, coronary angiographic quality scores were equivalent (left coronary artery 4.7 +/- 0.5 vs. 4.7 +/- 0.6, P = 0.99; right coronary artery 4.94 +/- 0.2 vs. 4.88 +/- 0.1, P = 0.21). Left ventriculography scores were lower in 4F Acist with similar contrast volumes. The total study contrast volume was significantly less in the 4F Acist group (119 +/- 35 vs. 149 +/- 49 ml, P = 0.001). Compared with the 4F manual contrast injection technique, diagnostic angiography through 4F catheters with power contrast injection resulted in equivalent coronary angiographic image quality with significantly less radiographic contrast volume.

Coronary angiography using 4 Fr catheters with acisted power injection: A randomized comparison to 6 Fr manual technique and early ambulation.

Coronary angiography using 4 Fr catheters may reduce access site complications, promote better utilization of outpatient facilities, but at a cost of suboptimal image quality. To determine whether 4 Fr diagnostic angiography with power injection (Acist, Minneapolis, MN) was equivalent to 6 Fr manual technique, 101 unselected patients were randomized to transfemoral coronary angiography with 4 or 6 Fr catheters. Procedural characteristics, angiographic quality scores, and results of 90 min ambulation were analyzed. Coronary angiographic quality scores using 4 Fr and 6 Fr catheters were equivalent (left coronary artery 4.73 +/- 0.6 vs. 4.80 +/- 0.65, P = 0.28; right coronary artery 4.98 +/- 90.13 vs. 4.97 +/- 0.16, P = 0.48). However, 4 Fr left ventriculographic image score was lower (4.53 +/- 0.68 vs. 4.83 +/- 0.42, P = 0.0002), attributed, in part, to a smaller injected contrast volume (32 +/- 11 vs. 37 +/- 4 mL, P = 0.001). The total study contrast volume was significantly less in the 4 Fr group (119 +/- 35 vs. 159 +/- 52 mL, P = 0.001). Complications related to early ambulation at 90 min were similar and minimal in both groups. Compared to 6 Fr manual contrast injection technique, diagnostic angiography through 4 Fr catheters with power contrast injection resulted in equivalent coronary angiographic image quality, slightly reduced but diagnostic left ventricular image quality, and significantly less contrast volume. Four Fr angiography facilitates early ambulation without compromising safety and image quality.

For left ventricular opacification and endocardial border definition: is it really important which contrast agent we use, or is it the imaging modality we choose?

AIMS: The purpose of this study was to prospectively compare the effect of three imaging modalities (fundamental, harmonics, and power harmonics) on left ventricular opacification and endocardial border definition with two different echo agents, Optison and Albunex. METHODS: A total of 84 patients who had suboptimal transthoracic images were studied with echo contrast agents Albunex (n=41) and Optison (n=43). Each contrast agent was examined with three different imaging modalities, fundamental, harmonics and power harmonics, respectively. Left ventricular opacification was obtained by videodensitometric analysis. Percentage of endocardial border visualization was determined by indexing circumference of visualized endocardium to total circumference. Variables were compared with respect to three imaging modalities between two different echo agents. RESULTS: Higher videointensities and higher percentages of endocardial visualization were achieved with Optison compared to Albunex with fundamental and harmonics. However, there was no significant difference between Optison and Albunex with respect to LV opacification and border visualization by power harmonics. CONCLUSION: These results indicate that left ventricular opacification and endocardial border visualization is significantly improved by using power harmonic imaging as compared to harmonics or fundamental imaging following both echo contrast agents. Furthermore, although Optison is clearly superior to Albunex in opacifying left ventricle, power harmonic imaging compensates for the less robust agent.

D-lactic acidosis 23 years after jejuno-ileal bypass.

Accumulation of D-lactate after gastrointestinal surgery, particularly jejuno-ileal bypass, is an uncommon and often misdiagnosed clinical disturbance. The syndrome may be complicated by dizziness, ataxia, confusion, headache, memory loss, and aggressive behavior. Serum chemistries are often deceptive because the anion gap is frequently normal in spite of severe metabolic acidosis. Moreover, the urine anion gap may be positive, incorrectly suggesting a defect in renal net acid excretion. Indeed, the combination of a normal anion gap metabolic acidosis and positive urine anion gap may erroneously suggest a diagnosis of renal tubular acidosis. Importantly, all reported cases of D-lactic acidosis secondary to bypass surgery have been encountered within 5 to 10 years following the surgery. Here we present an unusual case of D-lactic acidosis (complicated by encephalopathy) presenting 23 years after a jejuno-ileal bypass procedure. The patient was initially diagnosed with a drug intoxication secondary to benzodiazepines. Ultimately, the diagnosis of D-lactate encephalopathy was established after challenging the patient with a carbohydrate load. Thus, administration of 40 kcal/kg over 16 hours reproduced the clinical syndrome and was accompanied by a marked increment in serum and urine D-lactate concentration. The patient had sustained resolution of her symptoms after treatment with oral vancomycin.