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Background: Hypersensitivity pneumonitis (HP) refers to the inflammatory lung condition that results from inhalation of various (mostly organic) antigens leading to development of lymphocytic alveolitis and granulomatous pneumonitis. Pathogenesis of the disease is not fully understood and identification and removal of the causative agents remains the cornerstone of treatment and a major determinant of prognosis. Bronchoscopy and BAL can be used to characterize alveolitis and inflammatory cells infiltrate assuming to have a main role inthe pathogenesis of the disease process. Aim : to improve the characterization of alveolitis in HP on a number of patients with well-defined stages of disease activity and to assess the frequency of cellularity, CD4 and CD8 alveolitis. Subjects and methods: 88 HP cases diagnosed by thorough history, clinical examination, HRCT (with scoring system for each radiological pattern), spi rometry, and FOB with BAL for cellularity and flowcytometry (FCM) to determine CD4/CD8 ratio.Results: The mean total cell count (TCC)/cmm was (397±241) in subacute cases and (247±291) in chronic cases with statistically significant difference P-value 0.002. Mean lymphocytes percent was (45±19%) in subacute cases and 39±20% in chronic cases with no statistically significant value.

Sigma receptor is a transmembrane non-GPCR protein expressed mainly in the endoplasmic reticulum membrane associated with mitochondria. It is classified into two types: Sigma-1 (S1R) and Sigma-2 (S2R) based on their biological functions. S1R has been implicated in many neurological disorders such as anxiety, schizophrenia, and depression. Therefore, S1R ligands possess a variety of potential clinical applications with a great interest in the treatment of neuropathic pain. In this study, we report the discovery of a novel lead compound for S1R binding, based on the thiazolidine-2,4-dione nucleus. We have explored hydrophobic groups of different sizes on both sides of the five-membered ring scaffold guided by the crystal structure of S1R. Six compounds showed more than 50% displacement of the radioligand at 10 µM concentration with compound 6c resulting in 100% displacement and a K

The plasmodial kinases PfGSK3 and PfPK6 have been identified as essential for the asexual life stage of Plasmodium falciparum, and thus are considered viable novel drug targets to combat rising resistance to traditional antimalarial drugs. We recently identified disubstituted pyrimidine IKK16 as a compound which demonstrated strong activity against blood stage Pf3D7 parasites, while also exhibiting potent activity against PfGSK3 and PfPK6. Here we describe the synthesis of a series of IKK16 analogues and efforts to establish structure activity relationships to develop compounds with enhanced inhibition of PfPK6 and PfGSK3. We made extensive modifications focused on the 2, 4, and 5 positions of the pyrimidine core. The new synthesized compounds were assessed for enzymatic activity on PfGSK3 and PfPK6 using a split luciferase binding assay, and many of them displayed low nanomolar potency against both kinases. The most potent inhibitors were further assessed for activity against blood stage P. falciparum 3D7 parasites as well as liver stage P. berghei parasites. This culminated in the discovery of compounds 23d and 23e which displayed the most promising biological profiles among this set of analogues. Both compounds showed the greatest inhibitory activity against PfGSK3 and PfPK6 (23d PfGSK3 IC50 = 172 nM, PfPK6 IC50 = 11 nM, 23e PfGSK3 IC50 = 97 nM, PfPK6 IC50 = 8 nM) and demonstrated considerable activity against blood stage parasitemia (23d Pf3D7 EC50 = 552 nM, 23e Pf3D7 EC50 = 1400 nM). Also, the ligand efficiency of these compounds was greater than IKK16. Both compounds exhibited significant promiscuity when tested in a panel of human kinase targets. Taken together, our results suggest that dual PfPK6/PfGSK3 inhibitors with antiplasmodial activity can be identified. Our strategy of targeting two plasmodial kinases simultaneously and the structure activity results described herein sets the stage for further optimization efforts with the goal of identifying novel antiplasmodial agents.

Activating mutations in the EGFR kinase domain are known to be a common cause of Non-Small Cell Lung Cancer (NSCLC) and are thus targeted for treatment. First generation Tyrosine Kinase Inhibitors (TKIs) were used to treat NSCLC patients with the known activating mutations L858R and exon 19 deletion but were resisted by a second mutation T790M in the active site of the kinase domain. Second generation members of TKIs have an electrophilic moiety that can form a covalent bond with Cys797 and are effective against T790M EGFR but are toxic because they inhibit WT EGFR as well. Third generation TKIs, like Osimertinib, can bind to and irreversibly inhibit T790M mutants selectively, while sparing the wild-type enzyme. Thus, they possess a better safety profile and a wider therapeutic window. However, the reason behind their selectivity is still not well understood. In this study, computational MD simulations were carried out on Osimertinib in complex with both WT and L858R/T790M Double Mutant (DM) EGFR to provide an insight into the selectivity of Osimertinib and its molecular interactions within the active site. A high-resolution trajectory analysis showed that the key selectivity residues are Val726, met793, and Cys797. Interaction of Osimertinib with these residues is improved due to the T790M mutation which optimizes the ligand orientation for binding, as evident from the RMSD and the distances monitored. These results can provide guidance for the development of more selective 3rd generation EGFR TKIs.Communicated by Ramaswamy H. Sarma.

Combining short-acting and long-acting insulin analogs was a real challenge which was overcome by NovoNordisk through co-formulation of insulin aspart and insulin degludec in single dosage form. The proposed study provides a simple, short and reliable high-performance liquid chromatographic method with diode array detection which is developed and validated for the simultaneous determination of insulin aspart and insulin degludec in human plasma. The proposed method achieved good separation between the two analytes utilizing a C8-column at 350 C in a very short run time (6 min), with a simple, low cost and reliable extraction method through precipitation of plasma protein. Gradient elution is applied using mobile phase consisting of 0.1 M Sodium Sulfate (pH 3.4) and Acetonitrile. The method was validated according to EMA Guideline on Bioanalytical validation. The proposed method had linear range from 3.0 to 300 μg/mL for insulin aspart and from 3.5 to 300 μg/mL for insulin degludec. The intra- and inter-day precision of insulin aspart were 0.36 % - 3.33% and 1.59 % - 8.84 %, respectively, and accuracy was between-10.06 % and 3.09% The intra- and inter-day precision of insulin degludec were 0.29% - 1.93% and 0.89% - 5.14%, respectively, and accuracy was between -5.29% and 3.91%.

The flow field around a horizontal-axis wind turbine is analyzed numerically by solving the flow governing equations namely Reynolds’s Averaged Navier-Stokes (RANS). The effect of wind velocity on the flow field and the wall static pressure coefficient was examined. The numerical results were compared with the available experimental measurements from the open literature to verify model predictions which showed reasonable agreement. Then, the numerical model was used to investigate the effect of wind turbine shroud on the flow field and the generated power from the wind turbine. A parametric study was performed to examine the effect of different shroud geometries on the flow and the velocity at wind turbine rotor. The flow field around wind turbine rotor was calculated for the proper geometry of the shroud, and the developed torque was obtained and consequently the generated power. The performance of the shrouded wind turbine was compared to that of the un-shrouded wind turbine, and it was found that a considerable increase in the generated power was obtained using the shroud.

Phosphodiesterase-4 (PDE4) is responsible for the selective degradation of the 3ʹ-cyclic phosphate bonds of cAMP. A collection of twenty-three diverse 1,2,3,4-tertahydro-β-carboline- and indole-based analogues were synthesized and assessed for their inhibitory activity against human PDE4. The compounds were prepared using straightforward procedures and characterized using 1H- and 13C NMR, IR, and mass spectroscopy as well as elemental analysis. Fifteen of the prepared compounds exhibited significant inhibitory activity with IC50 values in the lower micromolar to upper nanomolar ranges. The most active compounds also showed good selectivity for PDE4 over the related enzyme family member, PDE5, with either insignificant or null% inhibition of the latter enzyme. The indole-based compounds, 21b and 21c, showed the most pronounced PDE4 inhibition with IC50 values of 754 and 664 nM, respectively. The PDE4B active site comprises both hydrophobic and solvent-filled pockets. The Hydrophobic pocket (Q) includes the invariant purine-selective Gln443 which is critical for cAMP. Below this Gln443 lies Phe446 which acts as a hydrophobic P-clamp stabilizing the ligand aromatic ring system. Molecular docking investigation showed preferential anchoring of the active compounds within the PDE4 active site through interactions between the indole nitrogens and the dimethoxy phenyl groups with key residues. Overall, the prepared compounds are novel and simple molecules with good potential for future optimization. Showing satisfactory predicted ADME/safety and drug-likeness properties, compound 21c is considered a promising lead for further optimization towards clinical investigation against inflammatory, auto-immune diseases, or certain types of cancer.

Stress testing of biopharmaceuticals plays an important role in preparation of their stability profiles through investigation of possible degradation pathways and identification of degradation products, so in this study Insulin Degludec which is a new generation ultra-long-acting basal insulin is subjected to stress conditions as different temperatures, different pH, oxidation, mechanical agitation, and repeated freeze and thaw cycles to generate possible degradation products and aggregation that are investigated by two new validated RP-HPLC and SEC-HPLC methods in addition to dynamic light scattering (DLS) and native polyacrylamide gel electrophoresis (Nu-PAGE). SEC-HPLC was used to investigate formation of aggregates whose results were correlated with those obtained from DLS and Nu-PAGE, while RP-HPLC was used to investigate any possible chemical modifications. The Proposed RP-method had limit of detection (LOD) and limit of quantitation (LOQ) of 0.012 mg/mL and 0.045 mg/mL respectively and accuracy of 99.22 ± 1.07 %, while the SEC methods had limit of detection (LOD) and limit of quantitation (LOQ) of 0.012 mg/mL and 0.031 mg/mL, respectively. The degradation pattern due to high temperature effect and oxidation is investigated by LC- tandem mass spectrometry. Results showed that Insulin degludec is highly stable under low temperature, mechanical agitation and repeated freeze and thaw stress conditions but elevated temperature and high acidic condition lead to formation of aggregates and also chemical modifications including deamidation, isomerization and oxidation. Such different chemical degradation pathways are due to presence of variable reactive moieties in Insulin degludec structure. Insulin degludec is highly vulnerable to oxidation at the sulfur containing cysteine residue in B chain in position B7 forming trioxidation derivative when exposed to hydrogen peroxide. Formation of A21-Asp and A18-Asp deamidated variants as well as B3-Asp and B3-isoAsp deamidated variants are prominent degradation pathways at neutral pH but at elevated temperature.

Selective antagonists for the kappa opioid receptor (KOP) have the potential to treat opiate and alcohol addiction, as well as depression and other CNS disorders. Over the years, the development of KOP-selective antagonists yielded very few successful compounds. Recently, N-substituted trans-3,4-dimethyl-4-(3-hydroxyphenyl)piperidines have emerged as a novel class of pure opioid receptor antagonists, including the marketed Mu opioid receptor (MOP) peripheral antagonist Alvimopan and the potent KOP antagonist JDTic. However, the selectivity determinants of this class of compounds towards the opioid receptor subtypes are still vague and understudied. In this work, we have performed Molecular Dynamics (MD) simulation to gain insights into the differential binding of this class of compounds into KOP, as exemplified by Alvimopan and JDTic. Our study indicated that the selectivity largely depends on ligands interaction with the selectivity pocket formed by Val108, Thr111, and Val118, supported by two additional polar and hydrophobic contacts with Asp138 and Trp287, respectively. Our results also demonstrate, for the first time, that non-morphinan ligands can still adopt the "message-address model" for KOP efficacy and selectivity by binding to Glu297.

Purpose This paper aims to analyze the pressure behavior in dual porosity reservoirs using different techniques in an attempt to correctly characterize reservoir properties. Pressure transient tests in naturally fractured reservoirs often exhibit non-uniform responses. Design/methodology/approach The pressure transient tests in naturally fractured reservoirs were analyzed using conventional semi-log analysis, type curve matching (using commercial software) and Tiab’s direct synthesis (TDS) technique. In addition, the TDS method was applied in case of a naturally fractured formation with a vertical hydraulic fracture. These techniques were applied to a single-layer, naturally fractured reservoir under pseudosteady state matrix flow. By studying the unique characteristics of the different flow regimes appear on the pressure and pressure derivative curves, various reservoir characteristics can be obtained such as permeability, skin factor and fracture properties. Findings For naturally fractured reservoirs, a comparison between the results semi-log analysis, software matching and TDS method is presented. In case of wellbore storage, early time flow regime can be obscured that lead to incomplete semi-log analysis. Furthermore, the type curve matching usually gives a non-uniqueness solution, as it needs all the flow regimes to be observed. However, the direct synthesis method used analytical equation to calculate reservoir and well parameters without type curve matching. For naturally fractured reservoirs with a vertical fracture, the pressure behavior of wells crossed by a uniform flux and infinite conductivity fracture is analyzed using TDS technique. The different flow regimes on the pressure derivative curve were used to calculate the fracture half-length in addition to other reservoir properties. Originality/value The results of different field cases showed that TDS technique offers several advantages compared to semi-log analysis and type curve matching. It can be used even if some flow regimes are not observed. Direct synthesis results are accurate compared to the available core data and the software matching results. It can be used to confirm the software matching results and to give reliable reservoir characteristics when there is lack of data.

Phosphodiesterase 4 is the primary enzyme responsible for degradation of the second messenger cAMP in many of the cells releasing proinflammatory mediators. Inhibition of this enzyme could help in the management of various inflammatory conditions such as asthma, chronic obstructive pulmonary disorder, arthritis, and psoriasis. In this study, two novel series of tetrahydro-β-carbolines were designed by combining the pharmacophoric features of both tadalafil and piclamilast. Twenty-two compounds were synthesized and assessed for Phosphodiesterase 4 inhibition, four of them showed superior activity to the reference compound IBMX. Docking studies showed that the prepared compounds interact with the crucial Gln443 with variable interactions with the hydrophobic pocket Q2. This is the first report of tetrahydro-β-carbolines as a scaffold for Phosphodiesterase 4 inhibition. Currently, further optimization of the substituents is carried out to fine-tune the hydrophobic interactions and enhance the potency of this novel series of inhibitors.

Summary The depletion performance of gas/condensate reservoirs is highly influenced by changes in fluid composition below the dewpoint. The long-term prediction of condensate/gas reservoir behavior is therefore difficult because of the complexity of both composition variation and two-phase-flow effects. In this paper, an integrated model was developed to simulate gas-condensate reservoir/well behavior. The model couples the compositional material balance or the generalized material-balance equations for reservoir behavior, the two-phase pseudo integral pressure for near-wellbore behavior, and outflow correlations for wellbore behavior. An optimization algorithm was also used with the integrated model so it can be used in history-matching mode to estimate original gas in place (OGIP), original oil in place (OOIP), and productivity-index (PI) parameters for gas/condensate wells. The model also can be used to predict the production performance for variable tubinghead pressure (THP) and variable production rate. The model runs fast and requires minimal input. The developed model was validated by use of different simulation cases generated with a commercial compositional reservoir simulator for a variety of reservoir and well conditions. The results show a good agreement between the simulation cases and the integrated model. After validating the integrated model against the simulated cases, the model was used to analyze production data for a rich-gas/condensate field (initial condensate/gas ratio of 180 bbl/ MMscf). THP data for four wells were used along with basic reservoir and production data to obtain original fluids in place and PIs of the wells. The estimated parameters were then used to forecast the gas and condensate production above and below the dewpoint. The model is also capable of predicting reservoir pressure, bottomhole flowing pressure, and THP and can account for completion changes when they occur.

Predicting the performance of wells in stress-dependent gas reservoirs can be quite challenging to most conventional reservoir engineering tools. In this paper, a fully coupled geomechanics and fluid flow analytical model was developed for modeling well performance in stress-dependent gas reservoirs. For tight and unconsolidated gas reservoirs that exhibits variable formation compressibility, reservoir compaction, and stress-dependent properties deterioration such as permeability and porosity, the geomechanics effect may not be ignored. All these physical contributes play an important role on well performance. The coupled model considered all these contributes and evaluate their impact on well productivity. The model also accounts for the effect of the transient flow period and variable producing conditions in addition to the effect of non darcy flow in gas wells. An optimization algorithm was used with the coupled model to estimate original gas in place and performance characteristics for each layer in case of multilayered gas reservoirs. Different simulation cases and selected examples from gas wells producing from stress dependent gas reservoirs are used to illustrate the coupled model application. The results from this study indicates that a fully coupled geomechanics and fluid-flow modeling approach is necessary for analyzing highly stress-sensitive gas reservoirs