Metallogenic implications of biotite chemical composition: Sample from Cu-Mo-Au mineralized granitoids of the Shah Jahan Batholith, NW Iran

Abstract Igneous biotite has been analyzed from three I-type calc-alkaline intrusives of the Shah Jahan Batholith in NW Iran, which host several Cu-Mo-Au prospects. The XMg (Mg/Mg+Fe) value of biotite is the most significant chemical factor and the relatively high value of XMg corresponds to relatively high oxidation states of magma (estimated fO2 is mostly 10−12.5 to 10−7.5 bars), which is in good agreement with their host intrusions' setting and related ore occurrences. Based on criteria of AlIV and AlVI values, all studied biotites are primary (AlVI = 0), and based on Altotal values (2.23–2.82 apfu) are in distinctive ranges of mineralized granitoid (Altotal=3.2 apfu). The maximum F content of biotite from the Shah Jahan intrusions is moderately higher than those from some other calc-alkaline intrusions related to Cu-Mo porphyries in the world, and in contrast, Cl content is relatively lower. It is likely a result of primary magmatic vs. secondary hydrothermal origin, as well as the Mg-rich characteristics of the biotite in Shah Jahan. XMg values do not correlate with F and Cl contents of biotite, suggesting that biotite records changes in the F/OH and Cl/OH ratios in coexisting melt/fluids. It is consistent with F-compatible and Cl-incompatible behavior during fractional crystallization of wet calc-alkaline I-type granitoid magma generated at subduction related arc settings. The fugacity ratios of (H2O/HF), (H2O/HCl) and (HF/HCl) magmatic solutions coexisting with biotite illustrate similar trends in the three intrusions, which can be due to parental magma sources and/or indicate occurrence of similar magmatic processes prior to or contemporaneous with exsolution of fluids from melt. The observed trends caused F-depletions and Cl-enrichments within developed magmatic-hydrothermal systems which are one of the essential characteristics of potential Cu-Mo-Au mineralized I-type granitoids

Studies on Dissolution Enhancement of Prednisolone, a Poorly Water-Soluble Drug by Solid Dispersion Technique

Introduction: Prednisolone is a class II substance according to the Biopharmaceutics Classification System. It is a poorly water soluble agent. The aim of the present study was to improve dissolution rate of a poorly water-soluble drug, prednisolone, by a solid dispersion technique. Methods: Solid dispersion of prednisolone was prepared with PEG 6000 or different carbohydrates such as lactose and dextrin with various ratios of the drug to carrier i.e., 1:10, 1:20 and 1:40. Solid dispersions were prepared by coevaporation method. The evaluation of the properties of the dispersions was performed using dissolution studies, Fourier-transform infrared spectroscopy and x-ray powder diffractometery. Results: The results indicated that lactose is suitable carriers to enhance the in vitro dissolution rate of prednisolone. The data from the x-ray diffraction showed that the drug was still detectable in its solid state in all solid dispersions except solid dispersions prepared by dextrin as carrier. The results from infrared spectroscopy showed no well-defined drug–carrier interactions for coevaporates. Conclusion: Solid dispersion of a poorly water-soluble drug, prednisolone may alleviate the problems of delayed and inconsistent rate of dissolution of the drug

Investigation on mineralization and genesis of stratiform copper in Cheshmeh-Konan area of Tasuj, East-Azarbaijan province

Cheshmeh-Konan area is located ~15 km northwest of Tasuj, East-Azarbaidjan province. The most important lithologic units of the area are red sandstones, green-gray sandstones, shale, and marl (Miocene). Based on field evidence and petrographical investigations, the host sediments were deposited in a peritidal setting associated with a sabkha-type environment. Copper mineralization in the area occurred as stratiform within the green-gray coarse-grained sandstones and includes minerals such as chalcocite, covellite, bornite, chalcopyrite, malachite, and azurite. Considering the obtained results, control of the mineralization in the area is in relation to sandstone sedimentary facies and concentration of organic matters. Combination of the obtained results from field, petrographical and mineralographical investigations indicate that factors such as accessibility to chloride ligands, presence of high quantities of organic matters, diagenetic processes, function of marls and shales as geochemical barriers, and the existence of fault systems have played a major role in copper mineralization at Chesmeh-Konan area. The obtained results show that copper mineralization in the area is mostly similar to Red Bed type sedimentary copper deposits

Interactions Between Sirolimus and Anti-Inflammatory Drugs: Competitive Binding for Human Serum Albumin

Purpose: The aim of the present study was investigating the effects of three anti-inflammatory drugs, on Sirolimus protein biding. The binding site of Sirolimus on human serum albumin (HSA) was also determined. Methods: Six different concentrations of Sirolimus were separately exposed to HSA at pH 7.4 and 37°C. Ultrafiltration method was used for separating free drug; then free drug concentrations were measured by HPLC. Finally, Sirolimus protein binding parameters was calculated using Scatchard plots. The same processes were conducted in the presence of NSAIDs at lower concentration of albumin and different pH conditions. To characterize the binding site of Sirolimus on albumin, the free concentration of warfarin sodium and Diazepam, site I and II specific probes, bound to albumin were measured upon the addition of increasing Sirolimus concentrations. Results: Based on the obtained results presence of Diclofenac, Piroxicam and Naproxen, could significantly decrease the percentage of Sirolimus protein binding. The Binding reduction was the most in the presence of Piroxicam. Sirolimus-NSAIDs interactions were increased in higher pH values and also in lower albumin concentrations. Probe displacement study showed that Sirolimus may mainly bind to site I on albumin molecule. Conclusion: More considerations in co-administration of NSAIDs and Sirolimus is recommended

The Effects of Cetirizine on P-glycoprotein Expression and Function In vitro and In situ

Purpose: P-glycoprotein (P-gp) plays a major role in oral absorption of drugs. Induction or inhibition of P-gp by drugs contributes to variability of its transport activity and often results in clinically relevant drug-drug interactions. The purpose of this study was to investigate the effect of cetirizine, a second generation H1 antihistamine, on P-gp function and expression in vitro and in situ. Methods: The in-vitro rhodamin-123 (Rho123) efflux assay in Caco-2 cells was used to study the effect of cetirizine on P-gp function. Western blot analysis was used for surveying the effect of cetirizine on expression of P-gp in Caco-2 cells. Rat in situ single-pass intestinal permeability technique was used to calculate the intestinal permeability of a known P-gp substrate (digoxin) in the presence of cetirizine. The amounts of digoxin and cetirizine in intestinal perfusion samples were analyzed using a HPLC method. Results: The results showed significant increase in Rho123 uptake (P < 0.05) and also P-gp band intensity decrease in cetirizine-treated cells in vitro. Furthermore the intestinal permeability of digoxin was also increased significantly in the presence of cetirizine (P < 0.01). Conclusion: Therefore it is concluded that cetirizine is a P-gp inhibitor and this should be considered in co administration of cetrizine with other P-gp substrate drugs. Further investigations are required to confirm our results and to determine the mechanism underlying P-gp inhibition by cetirizine

Inhibitory effect of clemastine on P-glycoprotein expression and function: an in vitro and in situ study

Objective(s):Transporters have an important role in pharmacokinetics of drugs. Inhibition or induction of drug transporters activity can affect drug absorption, safety, and efficacy. P-glycoprotein (P-gp) is the most important membrane transporter that is responsible for active efflux of drugs. It is important to understand which drugs are substrates, inhibitors, or inducers of P-gp to minimize or avoid unwanted interactions. The aim of this study was to investigate the effects of clemastine on the expression and function of P-gp. Materials and Methods: The effect of clemastine on P-gp function and expression was evaluated in vitro byrhodamine-123 (Rho123) efflux assay in Caco-2 cells and Western blot analysis. Rat in situ single pass intestinal permeability model was used to investigate the clemastine effect on digoxin Peff, as a known P-gp substrate. Digoxin levels in intestinal perfusates were assayed by high performance liquid chromatography (HPLC) method. Results:The Caco-2 intracellular accumulation of Rho123 in clemastine and verapamil treated cells was 90.8 ± 9.8 and 420.6±25.4 pg/mg protein, respectively which was significantly higher than that in control cells (50.2±6.0;

Dossier - Percorsi femminili e femministi tra Medio Oriente e Africa

Nel 2011 in Medio Oriente e in Africa si è prodotta una cesura rilevante che ha indotto studiosi/ e, analisti a ripensare in termini storiografici, sociologici, giuridici e antropologici le trasformazioni all’interno delle società della regione. Al centro di questo percorso assumono particolare rilevanza attori indispensabili per la costruzione delle società post-Primavere arabe, e in particolare le donne che, attraverso la loro pluralità, ci inducono a rivolgere lo sguardo a questi mondi e a ri-definire i percorsi di società in continuo mutamento. Diviene quindi sempre più necessario riprendere il filo di un’elaborazione teorica che alimenti un dibattito nuovo al fine di ri-definire gli studi di genere nell’area. In questo quadro il convegno “Percorsi femminili e femministi tra il Mediterraneo e l’Africa” si è posto l’obiettivo di avviare un dialogo interdisciplinare tra studiose/i al fine di comprendere a quale punto è la storia delle donne “dell’Altra Riva” e di sensibilizzare il mondo accademico e non solo. A dieci anni da quella fase che per la regione ha rappresentato una frattura con il passato, i women studies soffrono ancora di una marcata separazione dal dibattito storiografico, giuridico, sociologico e letterario. Ne risulta quindi una sorta di isolamento che impedisce ai women studies nel nostro paese di incidere al fine di una ridefinizione dei paradigmi