Diagnostic Accuracy of Computed Tomography Scan in Detection of Upper Gastrointestinal Tract Injuries Following Caustic Ingestion

Introduction: Endoscopy is an invasive procedure and finding noninvasive alternative tools in detection of probable upper gastrointestinal (GI) tract injuries following caustic ingestion is an area of interest. The present study aimed to evaluate the screening performance characteristics of thoraco-abdominal computed tomography (CT) scan in this regard.Methods: This prospective cross sectional study was conducted on patients presenting to emergency department following acute caustic ingestion. The findings of CT scan and endoscopy regarding the presence of upper GI tract damage were compared and screening performance characteristics of CT scan were calculated using MedCalc software.Results: 34 patients with the mean age of 35.38±13.72 years were studied (58.8% male). The agreement rate between CT scan and endoscopy regarding the grade of esophageal and gastric injuries was moderate (K= 0.38; p = 0.001) and fair (K= 0.17; p = 0.038), respectively. The sensitivity and specificity of CT scan in detection of esophageal damage were 96.29) 79.11- 99.80) and 57.14 (20.23 - 88.19), respectively. These measures were 89.65 (71.50 - 97.28) and 40.00 (7.25 - 82.95), respectively for gastric damage. The area under the ROC curve of CT scan in detection of esophageal and gastric damages was 0.76 (95% CI: 0.52 – 1.00) and 0.64 (95% CI: 0.35 – 0.94), respectively.Conclusion: Based on the findings of the present study, CT scan could be considered as a sensitive tool in ruling out upper gastrointestinal mucosal injuries following acute caustic ingestions. However, the correlation between endoscopy and CT scan findings regarding the grading of injury is not high enough to eliminate the need for endoscopy.

Reducing the 2, 4 D+MCPA Antagonism from Hard Spray Waters by Ammonium Sulfate

Introduction: Water is the main carrier of herbicides (HC) that its quality plays an important role in herbicide performance hard water has a high concentration of Ca++ and Mg++ and reviews have shown that calcium, manganese and zinc are the main factors reducing the effectiveness of weak acid herbicides. Weak acid herbicides such as glyphosate, paraquat, clethodim and 2, 4 D are compounds that release the H+ ions once dissolved in water, but just slightly. Therefore, herbicides that are weak acids partially dissociate. Herbicides not dissociated (the compound remains whole) are more readily absorbed by plant foliage than those that dissociate. Dissociated herbicide molecules have a negative charge. After being dissociated, herbicides might remain as negatively charged molecules, or they might bind with other positively charged cations. Binding to some cations improves herbicide uptake and absorption, binding to others such as Ca++ and Mg++ antagonizes herbicide activity by decreasing absorption or activity in the cell. To correct such carriers, the use of adjuvants, such as ammonium sulphate (AMS), is recommended, which can reduce the use of herbicides and cause economic savings. The aim of this study was to investigate the simple effects and interactions between different amounts of AMS and carrier hardness (CH) levels on 2, 4 D + MCPA herbicide efficacy in controlling white clover (Trifolium repens L.) in turf grass. Materials and Methods: The experiment was laid out in a RCBD with three replications for each treatment during spring-summer 2013 in 10 years old mixed cold season turf grass (Festuca rubra + Poa pratensis + Poa pratensis) dominated by white clover in Mashhad (Iran). The treatments were the factorial combination of four carrier hardness (CH) rates (Deionized, 45, 90 and 180 ppm of Ca++ +Mg++) and three Ammonium Sulfate (AMS) rates (0, 2, 3 and 4 Kg per100 L of carrier water) were studied. The turf was sprayed with 2, 4 D + MCPA (67.5% SL) at 1.5 L-ha applied once on July. The density and dry matter of clover and turf were recorded. Results and Discussion: Full performance of 2, 4 D + MCPA herbicide to control clover, regardless of the amount of ammonium sulfate used, was obtained in soft water. Adding just 4%, AMS to Carrier water with a hardness of 45 ppm could recover effectiveness of herbicide up to DI water, whereas in 90 ppm of hardness adding only 2 percent ammonium sulfate was enough to increase herbicide efficacy to twice as no ammonium sulfate treatment. The most significant antagonism effect was obtained in 180 ppm hardness level without AMS reducing 84% of 2, 4 D + MCPA performance compared to soft water. The highest antagonism effect of the herbicide carrier went to 180 ppm, 90 ppm and 45 ppm of hardness respectively. Overall, the study revealed that only in 45 ppm of CH the addition of 4% of AMS will help to restore the toxicity of 2, 4 D + MCPA while in 90 ppm and 180 ppm of CH add more than 2% of AMS to 2, 4 D + MCPA carrier water will not benefit the herbicide toxicity. Most reports have considered sufficient two percent of AMS to neutralize the inhibitory effect of CH on the weak acid herbicides. Three weeks after spraying, no phytotoxicity was found in the grass. At the same time interaction between CH and AMS on the lawn dry weight was significant (

Cytotoxic Effects of Newly Synthesized Palladium(II) Complexes of Diethyldithiocarbamate on Gastrointestinal Cancer Cell Lines

As a part of a drug development program to discover novel therapeutic and more effective palladium (Pd) based anticancer drugs, a series of water-soluble Pd complexes have been synthesized by interaction between [Pd (phen)(H2O)2(NO3)2] and alkylenebisdithiocarbamate(al-bis-dtc) disodium salts. This study was undertaken to examine the possible cytotoxic effect of three novel complexes (0.125–64 µg/mL) on human gastric carcinoma (AGS), esophageal squamous cell carcinoma (Kyse-30), and hepatocellular carcinoma (HepG2) cell lines. The cytotoxicity was examined using cell proliferation and acridine orange/ethidium bromide (AO/EB) assay. In order to examine the effects of new Pd(II) complexes on cell cycle status, we performed cell cycle analysis. The complexes were found to have completely lethal effects on the cell lines, and the half maximal inhibitory concentration (IC50) values obtained for the cell lines were much lower in comparison with cisplatin. We demonstrated that the three new Pd(II) complexes are able to induce G2/M phase arrest in AGS and HepG2; in addition, the Pd(II) complexes caused an S phase arrest in Kyse-30 cell line. Our results indicate that newly synthesized Pd(II) complexes may provide a novel class of chemopreventive compounds for anticancer therapy

Design and evaluation of an apta-nano-sensor to detect Acetamiprid <i>in vitro</i> and <i>in silico</i>

<p>Pesticide detection is a main concern of food safety experts. Therefore, it is urgent to design an accurate, rapid, and cheap test. Biosensors that detect pesticide residues could replace current methods, such as HPLC or GC-MC. This research designs a biosensor based on aptamer (Oligonucleotide ss-DNA) in the receptor role, silver nanoparticles (AgNPs) as optical sensors and salt (NaCl) as the aggregative inducer of AgNPs to detect the presence of Acetamiprid. After optimization, .6 μM aptamer and 100 mM salt were employed. The selectivity and sensitivity of the complex were examined by different pesticides and different Acetamiprid concentrations. To simulate <i>in vitro</i> experimental conditions, bioinformatics software was used as <i>in silico</i> analysis. The results showed the detection of Acetamiprid at the .02 ppm (89.8 nM) level in addition to selectivity. Docking outputs introduced two loops as active sites in aptamer and confirmed aptamer–Acetamiprid bonding. Circular dichroism spectroscopy (CD) confirmed upon Acetamiprid binding, aptamer was folded due to stem-loop formation. Stability of the Apt–Acetamiprid complex in a simulated aqueous media was examined by molecular dynamic studies.</p

HONO Formation from the Oxidation Reactions of ClO, NO, and Water in the Gas-Phase and at the Air-Water Interface

Nitrous acid (HONO) plays a key role in atmospheric chemistry. Nevertheless, the HONO formation mechanism in the atmosphere, especially in the marine boundary layer, remains to be fully understood. Here, Born–Oppenheimer molecular dynamic and metadynamics simulations were performed to study the formation mechanism of HONO from the oxidation reactions of ClO radical and NO with the addition of (H2O)1–2, considering a monohydrated system ((ClO)(NO)(H2O)1) and dihydrated system ((ClO)(NO)(H2O)2), as well as at the air-water interface. This study shows that HONO formation follows a single-water mechanism in gas-phase and air-water interface systems. The free-energy barrier of the (ClO)(NO)(H2O)1 system was 9.66 kJ mol−1, whereas the (ClO)(NO)(H2O)2 system was a barrierless reaction. HONO formation at the air-water interface was faster than that in monohydrated and dihydrated systems. Although the concentration of ClO radical in the marine boundary layer is two orders higher than that of Cl radical, the production rates of HONO from the (ClO)(NO)(H2O)1 system are six orders lower than that from the (Cl)(NO)(H2O)1 system, which means that Cl radical dominates HONO formation rather than ClO radical in the marine boundary layer. These results can deepen our understanding of the HONO formation mechanism and be used to reduce HONO emissions and establish HONO-control strategies

The Homogeneous Gas-Phase Formation Mechanism of PCNs from Cross-Condensation of Phenoxy Radical with 2-CPR and 3-CPR: A Theoretical Mechanistic and Kinetic Study

Chlorophenols (CPs) and phenol are abundant in thermal and combustion procedures, such as stack gas production, industrial incinerators, metal reclamation, etc., which are key precursors for the formation of polychlorinated naphthalenes (PCNs). CPs and phenol can react with H or OH radicals to form chlorophenoxy radicals (CPRs) and phenoxy radical (PhR). The self-condensation of CPRs or cross-condensation of PhR with CPRs is the initial and most important step for PCN formation. In this work, detailed thermodynamic and kinetic calculations were carried out to investigate the PCN formation mechanisms from PhR with 2-CPR/3-CPR. Several energetically advantageous formation pathways were obtained. The rate constants of key elementary steps were calculated over 600~1200 K using the canonical variational transition-state theory (CVT) with the small curvature tunneling (SCT) contribution method. The mechanisms were compared with the experimental observations and our previous works on the PCN formation from the self-condensation of 2-CPRs/3-CPRs. This study shows that naphthalene and 1-monochlorinated naphthalene (1-MCN) are the main PCN products from the cross-condensation of PhR with 2-CPR, and naphthalene and 2-monochlorinated naphthalene (2-MCN) are the main PCN products from the cross-condensation of PhR with 3-CPR. Pathways terminated with Cl elimination are preferred over those terminated with H elimination. PCN formation from the cross-condensation of PhR with 3-CPR can occur much easier than that from the cross-condensation of PhR with 2-CPR. This study, along with the study of PCN formation from the self-condensation 2-CPRs/3-CPRs, can provide reasonable explanations for the experimental observations that the formation potential of naphthalene is larger than that of 1-MCN using 2-CP as a precursor, and an almost equal yield of 1-MCN and 2-MCN can be produced with 3-CP as a precursor

Theoretical Perspectives on the Gas-Phase Oxidation Mechanism and Kinetics of Carbazole Initiated by OH Radical in the Atmosphere

Carbazole is one of the typical heterocyclic aromatic compounds (NSO-HETs) observed in polluted urban atmosphere, which has become a serious environmental concern. The most important atmospheric loss process of carbazole is the reaction with OH radical. The present work investigated the mechanism of OH-initiated atmospheric oxidation degradation of carbazole by using density functional theory (DFT) calculations at the M06-2X/6-311++G(3df,2p)//M06-2X/6-311+G(d,p) level. The rate constants were determined by the Rice&ndash;Ramsperger&ndash;Kassel&ndash;Marcus (RRKM) theory. The lifetime of carbazole determined by OH was compared with other typical NSO-HETs. The theoretical results show that the degradation of carbazole initiated by OH radical includes four types of reactions: OH additions to &ldquo;bend&rdquo; C atoms, OH additions to &ldquo;benzene ring&rdquo; C atoms, H abstractions from C-H bonds and the H abstraction from N-H bond. The OH addition to C1 atom and the H abstraction from N-H bond are energetically favorable. The main oxidation products are hydroxycarbazole, dialdehyde, carbazolequinone, carbazole-ol, hydroxy-carbazole-one and hydroperoxyl-carbazole-one. The calculated overall rate constant of carbazole oxidation by OH radical is 6.52 &times; 10&minus;12 cm3 molecule&minus;1 s&minus;1 and the atmospheric lifetime is 37.70 h under the condition of 298 K and 1 atm. The rate constant of carbazole determined by OH radical is similar with that of dibenzothiophene oxidation but lower than those of pyrrole, indole, dibenzofuran and fluorene. This work provides a theoretical investigation of the oxygenated mechanism of NSO-HETs in the atmosphere and should help to clarify their potential health risk for determining the reaction pathways and environmental influence of carbazole