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Background and Aims: The cellular mechanisms responsible for initiating or limiting the tumors including skin types are of great importance. The p53 is a tumor-inhibiting gene which is believed to be defective in many malignant situations. Ki67 is a non-histonic protein which is mainly interfere with the proliferation and has many controlling effects during the cell cycle. Because of their importance in skin tumor cell growth, this study aimed at evaluating the p53 and Ki67 expression in skin epithelial tumors by immunohistochemical method. Materials and Methods: In a descriptive setting, 50 biopsy samples (30 basal cell carcinomas (BCCs), 10 squamous cell carcinomas (SCCs), 8 keratoacanthomas (KAs), and 2 trichoepitheliomas (TEs)) were immunohistochemically evaluated for p53 and Ki67 expression during a 14-month period. The incidence and expression rate of these two variables were separately reported in each group of samples. Results: The expression rate of p53 was 67.77% for the BCCs, 50.20% for the SCCs, and null for the KAs. For both TEs, it was 50%. The expression rate of Ki67 was 57.33% for the BCCs, 47.70% for the SCCs, 37.5% for the KAs, and 0.0% for TEs. The incidence of P53+ cells was 100% and 90% in the BCC and SCC samples, respectively. The both TEs were positive in this regard. The incidence of Ki67+ cells was 100% for the BCC, SCC, and KA samples. The both TEs were negative in this regard. Conclusion: This study showed that the incidence rate of p53- and Ki67-positive cells is very high in skin malignant epithelial tumors. The expression rate of these two variables is comparable with reports in the literature. Further studies with large sample size are recommended to be carried out for KA and TE samples.

Fe3O4@MgAl-LDH as a new magnetic nanocatalyst was developed for phenol removal from wastewater in the catalytic wet peroxide oxidation process. It was synthesized by co-precipitation and characterized by X-ray diffraction, Fourier-transform infrared spectroscopy, vibrating sample magnetometer, field-emission scanning electron microscopy/energy-dispersive X-ray spectroscopy, and Brunauer–Emmett–Teller. The results confirmed that Fe3O4@MgAl-LDH is a super-magnetic nanocomposite with a specific saturation magnetization (Ms) of 18.63 emu g−1 and a specific surface area of 235.8 m² g–1. The modelling of the process was done using both response surface methodology (RSM) and artificial neural network (ANN). The Pareto analysis indicated that the relative importance of the process variables is as following: phenol concentration > volume of peroxide > dosage of the catalyst > reaction time. The optimum condition was at 0.5 g L–1, 100 min, 0.7 mL, 65.15 ppm of catalyst amount, reaction time, peroxide volume and phenol concentration, respectively. The predicted response under optimum conditions was 96%, whereas the experimental response resulted in 98%. The feed-forward back-propagation was used for ANN modelling including the topology of 4 input variables, 8 neurons in the hidden layer and 1 output. The training of the network was accomplished by a Levenberg–Marquardt. The mean square error for the ANN and RSM models were 0.22 and 0.87, respectively, and the R² values were 0.99 and 0.98, respectively. It is concluded that black-box ANN indicates a higher accuracy in estimating phenol remediation. The study showed that magnetic layered double hydroxides could be a promising catalyst for phenol removal from wastewaters. [ABSTRACT FROM AUTHOR]

The CBS‐APNO and CBS‐QB3 model chemistries have been used to study the temperature‐ and pressure‐dependent kinetics of degenerate Cope rearrangement of hypostrophene. The rate constants are calculated by means of RRKM theory and corrected by the Wigner tunneling correction. The high‐ and low‐pressure limits of the rate constants reveal that the TST is valid to estimate the rate constant at 1 bar and the reaction in the bimolecular region cannot be observed experimentally. The estimated rate constant and activation energy at 1 bar and 308 K are 10−2 s−1 and 89 kJ.mol−1, respectively, such that the homoaromatic transition structure is stabilized by 85 kJ.mol−1 because of the interactions between the allyl moieties. Evolution of chemical events along the reaction has been analyzed by the BET together with the NCI and AIM topological approaches at the B3LYP with 6‐311G(d,p) basis set. The progress of reaction was monitored by five SSDs and controlled by the succession of catastrophes C†[F]2TS[F†]2C. The sequential chemical events consist of homolytic rupture of C−C bond and formation of pseudoradical centers on carbon atoms, disappearance of the generated pseudoradical centers, formation of new pseudoradical centers on two carbon, and formation of new C−C single bond through the C− to −C coupling of the generated pseudoradical centers. The NCI and AIM analyses have been performed to study the nature of the interaction in the regions where bond rupture/formation occur. [ABSTRACT FROM AUTHOR]

Background and Aims: The cellular mechanisms responsible for initiating or limiting the tumors including skin types are of great importance. The p53 is a tumor?inhibiting gene which is believed to be defective in many malignant situations. Ki67 is a non?histonic protein which is mainly interfere with the proliferation and has many controlling effects during the cell cycle. Because of their importance in skin tumor cell growth, this study aimed at evaluating the p53 and Ki67 expression in skin epithelial tumors by immunohistochemical method. Materials and Methods: In a descriptive setting, 50 biopsy samples (30 basal cell carcinomas (BCCs), 10 squamous cell carcinomas (SCCs), 8 keratoacanthomas (KAs), and 2 trichoepitheliomas (TEs)) were immunohistochemically evaluated for p53 and Ki67 expression during a 14?month period. The incidence and expression rate of these two variables were separately reported in each group of samples. Results: The expression rate of p53 was 67.77% for the BCCs, 50.20% for the SCCs, and null for the KAs. For both TEs, it was 50%. The expression rate of Ki67 was 57.33% for the BCCs, 47.70% for the SCCs, 37.5% for the KAs, and 0.0% for TEs. The incidence of P53+ cells was 100% and 90% in the BCC and SCC samples, respectively. The both TEs were positive in this regard. The incidence of Ki67+ cells was 100% for the BCC, SCC, and KA samples. The both TEs were negative in this regard. Conclusion: This study showed that the incidence rate of p53?.and Ki67?positive cells is very high in skin malignant epithelial tumors. The expression rate of these two variables is comparable with reports in the literature. Further studies with large sample size are recommended to be carried out for KA and TE samples. [ABSTRACT FROM AUTHOR]

The dependence of L-glutamine protonation and its complexation with dioxovanadium(V) on ionic strength (I) is reported in sodium perchlorate solution as a background salt. The measurements have been performed at 25 ± 0.1°C and various ionic strengths in the range 0.1 to 1.0 mol/l, using a combination of potentiometric and spectrophotometric techniques. The overall analysis of the present and the previous data dealing with the determination of stability constants at different ionic strengths allowed us to obtain a general equation, by which a formation constant determined at a fixed ionic strength can be calculated, with a good approximation, at another ionic strength, if 0.1 ≤ I ≤ 1.0 mol/l (NaClO4). [ABSTRACT FROM AUTHOR]