DIACEREIN-LOADED NIOSOMES (DC-NS): A NEW TECHNIQUE TO SUSTAIN THE RELEASE OF DRUG ACTION

Objective: The study's main goal is to develop a suitable niosomes (NS) encapsulated drug for anti-inflammatory effects such as diacerein (DC) and to evaluate the system's vesicle size (VS), entrapment efficiency (EE %), physical stability and in vitro release. Methods: Tween (40 and 60), cholesterol, and stearylamine were used in a 1:1:0.1 molar ratios as non-ionic surfactants. Thin film hydration was used to create the NS. Results: The higher EE% was observed with NS (F11) prepared from tween 60, cholesterol and 2.5 min sonication. These formulations' release patterns were Higuchi diffusion and first order. For the stability study, NS formulations were stored at temperature between 2-8 °C for 60 d retains the most drugs when compared to room and high temperature conditions. Conclusion: The findings of this study have conclusively shown that after NS encapsulation of DC, drug release is prolonged at a constant and controlled rate

DEVELOPMENT OF SUSTAINED RELEASE ALOGLIPTIN TABLETS USING A MULTIPARTICULATES SYSTEM MADE OF BENTONITE

Objective: This study was designed to evaluate the use of bentonite in the formulation of sustained-release tablets containing alogliptin benzoate after granulation. Methods: Bentonite was used for preparing tablets after granulation. The prepared tablets were tested for their pharmacopeial requirements. Further, a high-performance liquid chromatography (HPLC) method was developed to assess the release pattern of alogliptin from the tablets. Besides, differential scanning calorimetry (DSC), fourier transform infrared spectroscopy (FTIR), and powder X-ray diffraction (XRD) were used for evaluating the compatibility the drugs and bentonite. Finally, the release from the tablets was tested using the paddle apparatus. Results: The FTIR and DSC did not show any interaction between the drug and the excipient in contrast to the powder-XRD pattern, which showed a shift for montmorillonite crystal peak. This shift was interpreted by increasing in the spacing of the crystalline structure of montmorillonite. However, the results of pharmacopeial tests showed that the prepared tablets comply with the compendial requirements, In addition, the release profiles of these tablets with aid of hydroxypropyl methylcellulose (HPMC) as a binder revealed a sustained release of alogliptin. Furthermore, the fitting of release data showed that the release from these tablets followed Fickian diffusion that alogliptin released by diffusion from bentonite gel matrix. Conclusion: Bentonite was successfully used for producing sustained-release tablets of alogliptin. However, maintaining the crystal structure of montmorillonite was essential for building the gel structure of bentonite and releasing the drug in a controlled manner

Design, synthesis, and DNA interaction studies of furo-imidazo[3.3.3] propellane derivatives : Potential anticancer agents

A large number of natural products containing the propellane scaffold have been reported to exhibit cytotoxicity against several cancers; however, their mechanism of action is still unknown. Anticancer drugs targeting DNA are mainly composed of small planar molecule/s that can interact with the DNA helix, causing DNA malfunction and cell death. The aim of this study was to design and synthesize propellane derivatives that can act as DNA intercalators and/or groove binders. The unique structure of the propellane derivatives and their ability to display planar ligands with numerous possible geometries, renders them potential starting points to design new drugs targeting DNA in cancer cells. New substituted furo-imidazo[3.3.3]propellanes were synthesized via the reaction of substituted alkenylidene-hydrazinecarbothioamides with 2-(1,3-dioxo-2,3-dihydr- 1H-2-ylidene) propanedinitrile in tetrahydrofuran at room temperature. The structures of the products were confirmed by a combination of elemental analysis, NMR, ESI-MS, IR and single crystal X-ray analysis. Interestingly, 5c, 5d and 5f showed an ability to interact with Calf Thymus DNA (CT-DNA). Their DNA-binding mode was investigated using a combination of absorption spectroscopy, DNA melting, viscosity, CD spectroscopy measurements, as well as competitive binding studies with several dyes. Their cytotoxicity was evaluated against the NCI-60 panel of cancer cell lines. 5c, 5d and 5f exhibited similar anti-proliferative activity against the A549 non-small cell lung cancer (NSCLC) cell line. Further mechanistic studies revealed their ability to induce DNA damage in the A549 cell line, as well as apoptosis, evidenced by elevated Annexin V expression, enhanced caspase 3/7 activation and PARP cleavage. In this study, we present the potential for designing novel propellanes to provoke cytotoxic activity, likely through DNA binding-induced DNA damage and apoptosis.Peer reviewe

Design, synthesis and biological evaluation of fused naphthofuro[3,2-c]quinoline-6,7,12-triones and pyrano[3,2-c]quinoline-6,7,8,13-tetraones derivatives as ERK inhibitors with efficacy in BRAF-mutant melanoma

Approximately 60% of human cancers exhibit enhanced activity of ERK1 and ERK2, reflecting their multiple roles in tumor initiation and progression. Acquired drug resistance, especially mechanisms associated with the reactivation of the MAPK (RAF/MEK/ERK) pathway represent a major challenge to current treatments of melanoma and several other cancers. Recently, targeting ERK has evolved as a potentially attractive strategy to overcome this resistance. Herein, we report the design and synthesis of novel series of fused naphthofuro[3,2-c] quinoline-6,7,12-triones 3a-f and pyrano[3,2-c]quinoline-6,7,8,13-tetraones 5a,b and 6, as potential ERK inhibitors. New inhibitors were synthesized and identified by different spectroscopic techniques and X-ray crystallography. They were evaluated for their ability to inhibit ERK1/2 in an in vitro radioactive kinase assay. 3b and 6 inhibited ERK1 with IC50s of 0.5 and 0.19 mu M, and inhibited ERK2 with IC50s of 0.6 and 0.16 mu M respectively. Kinetic mechanism studies revealed that the inhibitors are ATP-competitive inhibitors where 6 inhibited ERK2 with a K-i of 0.09 mu M. Six of the new inhibitors were tested for their in vitro anticancer activity against the NCI-60 panel of tumor cell lines. Compound 3b and 6 were the most potent against most of the human tumor cell lines tested. Moreover, 3b and 6 inhibited the proliferation of the BRAF mutant A375 melanoma cells with IC50s of 3.7 and 0.13 mu M, respectively. In addition, they suppressed anchorage-dependent colony formation. Treatment of the A375 cell line with 3b and 6 inhibited the phosphorylation of ERK substrates p-90RSK and ELK-1 and induced apoptosis in a dose dependent manner. Finally, a molecular docking study showed the potential binding mode of 3b and 6 within the ATP catalytic binding site of ERK2.Peer reviewe

Ruminant Brucellosis in the Kafr El Sheikh Governorate of the Nile Delta, Egypt: Prevalence of a Neglected Zoonosis

Brucellosis is a zoonosis of mammals caused by bacteria of the genus Brucella. It is responsible for a vast global burden imposed on human health through disability and on animal productivity. In humans brucellosis causes a range of flu-like symptoms and chronic debilitating illness. In livestock brucellosis causes economic losses as a result of abortion, infertility and decreased milk production. The main routes for human infection are consumption of contaminated dairy products and contact with infected ruminants. The control of brucellosis in humans depends on its control in ruminants, for which accurate estimates of the frequency of infection are very useful, especially in areas with no previous frequency estimates. We studied the seroprevalence of brucellosis and its geographic distribution among domestic ruminants in one governorate of the Nile Delta region, Egypt. In the study area, the seroprevalence of ruminant brucellosis is very high and has probably increased considerably since the early 1990s. The disease is widespread but more concentrated around major animal markets. These findings question the efficacy of the control strategy in place and highlight the high infection risk for the animal and human populations of the area and the urgent need for an improved control strategy

A Model of a MAPK•Substrate Complex in an Active Conformation: A Computational and Experimental Approach

The mechanisms by which MAP kinases recognize and phosphorylate substrates are not completely understood. Efforts to understand the mechanisms have been compromised by the lack of MAPK-substrate structures. While MAPK-substrate docking is well established as a viable mechanism for bringing MAPKs and substrates into close proximity the molecular details of how such docking promotes phosphorylation is an unresolved issue. In the present study computer modeling approaches, with restraints derived from experimentally known interactions, were used to predict how the N-terminus of Ets-1 associates with ERK2. Interestingly, the N-terminus does not contain a consensus-docking site ((R/K)2-3-X2-6-ΦA-X-ΦB, where Φ is aliphatic hydrophobic) for ERK2. The modeling predicts that the N-terminus of Ets-1 makes important contributions to the stabilization of the complex, but remains largely disordered. The computer-generated model was used to guide mutagenesis experiments, which support the notion that Leu-11 and possibly Ile-13 and Ile-14 of Ets-1 1-138 (Ets) make contributions through binding to the hydrophobic groove of the ERK2 D-recruiting site (DRS). Based on the modeling, a consensus-docking site was introduced through the introduction of an arginine at residue 7, to give the consensus 7RK-X2-ΦA-X-ΦB13. This results in a 2-fold increase in kcat/Km for the phosphorylation of Ets by ERK2. Similarly, the substitution of the N-terminus for two different consensus docking sites derived from Elk-1 and MKK1 also improves kcat/Km by two-fold compared to Ets. Disruption of the N-terminal docking through deletion of residues 1-23 of Ets results in a 14-fold decrease in kcat/Km, with little apparent change in kcat. A peptide that binds to the DRS of ERK2 affects Km, but not kcat. Our kinetic analysis suggests that the unstructured N-terminus provides 10-fold uniform stabilization of the ground state ERK2•Ets•MgATP complex and intermediates of the enzymatic reaction

Seasonal Oscillation of Human Infection with Influenza A/H5N1 in Egypt and Indonesia

As of June 22, 2011, influenza A/H5N1 has caused a reported 329 deaths and 562 cases in humans, typically attributed to contact with infected poultry. Influenza H5N1 has been described as seasonal. Although several studies have evaluated environmental risk factors for H5N1 in poultry, none have considered seasonality of H5N1 in humans. In addition, temperature and humidity are suspected to drive influenza in temperate regions, but drivers in the tropics are unknown, for H5N1 as well as other influenza viruses. An analysis was conducted to determine whether human H5N1 cases occur seasonally in association with changes in temperature, precipitation and humidity. Data analyzed were H5N1 human cases in Indonesia (n = 135) and Egypt (n = 50), from January 1, 2005 (Indonesia) or 2006 (Egypt) through May 1, 2008 obtained from WHO case reports, and average daily weather conditions obtained from NOAA's National Climatic Data Center. Fourier time series analysis was used to determine seasonality of cases and associations between weather conditions and human H5N1 incidence. Human H5N1 cases in Indonesia occurred with a period of 1.67 years/cycle (p<0.05) and in Egypt, a period of 1.18 years/cycle (p≅0.10). Human H5N1 incidence in Egypt, but not Indonesia, was strongly associated with meteorological variables (κ2≥0.94) and peaked in Egypt when precipitation was low, and temperature, absolute humidity and relative humidity were moderate compared to the average daily conditions in Egypt. Weather conditions coinciding with peak human H5N1 incidence in Egypt suggest that human infection may be occurring primarily via droplet transmission from close contact with infected poultry

EZETIMIBE NANOSTRUCTURED LIPID CARRIERS (NLCs): A NEW TECHNIQUE TO OVERCOME THE LIMITATIONS OF ORAL ADMINISTRATION

Objective: Ezetimibe (EMB) is a commonly used lipid-lowering medication that lowers cholesterol and triglycerides. Because of its lower water solubility and hepatic metabolism, it necessitates the formulation of drug delivery systems that are capable of improving solubility and avoiding hepatic effect. Methods: Ezetimibe nanostructured lipid carriers (EMB-NLCs) were formulated and examined. They were formulated through emulsification with a high homogenization speed and ultrasonication (The method and evaluation parameters have been mentioned under method section in Formulation of EMB-NLCs paragraph). Results: The formulated NLCs have exhibited particle size (P. S.) between 163.6±7.20 and 866.66±18.65 nm and the zeta potential (Z. P.) values have ranged between-24±1.25 and-35±0.25 mV. Besides, they exhibited higher EE% than 77 percent and the drug encapsulated in lipid matrix was in amorphous state. Pharmacokinetics of optimized formula (F1; composed of 2% w/w Gelucire® 43/01, 8% w/w Miglyol® 812 N, 0.5% w/w lecithin and 2% w/w Poloxmer® 188) have exhibited 2.63-and 2.33-fold increase in oral bioavailability in comparison with EMB suspension and marketing product (Ezetrol® 10 mg tablet), respectively. Conclusion: These studies have demonstrated that, NLCs are superior for enhancing in vivo behavior and oral bioavailability of EMB

Studying the rheological properties and the influence of drag reduction on a waxy crude oil in pipeline flow

The present work studies the effect of a commercially type of drag reducing agent on the crude oil production flow lines located in the Egyptian western desert (Fagour field) and owned by Khalda Petroleum Company. The drag reducing agent used in this study is a high molecular weight poly alpha olefin prepared by emulsion polymerization technique and supplied under trade name of LP-111. The results showed that this drag reducing agent (DRA) has great effects on the pressure drop and fanning factor. After the field application of 60 ppm of the DRA, the pressure drop was decreased by 36% at the pipeline capacity of 18,804 bbl/day. The fanning number and shear stress were decreased by the same percentage of 47%. The capacity of production line can be increased by 38% all over the two pipeline section due to the great reduction of pressure drop. The rheological behaviors of tested waxy crude oil were studied at different temperatures (varies from 67 to 102 °F) and different DRA concentrations (10, 20, 30, 40, and 50 ppm). The results showed that at all constant DRA concentrations, the viscosity highly decreased until 80 °F (above pour point by 15 °F). However, by increasing the DRA concentration, the viscosity is increased at temperatures lower than 80 °F. This is because the DRA is a high molecular weight polymer which participates in increasing viscosity by increasing its concentration. After 80 °F, the DRA concentration has an insignificant effect on viscosity. So the effect of the DRA is not in reducing viscosity but mainly in reducing the degree of turbulence energy. The field studies were performed at a normal temperature of tested pipeline sections (100 °F). The tested DRA has an improving effect on reducing the pressure drop of pipeline which leads to reduction in crude oil pumping energy or an increase in the pipeline capacity with a high efficiency of the DRA