Day: December 21, 2022

Hu, H. published the artcileEngineering of a spider peptide via conserved structure-function traits optimizes sodium channel inhibition in vitro and anti-nociception in vivo, SDS of cas: 21829-25-4, the main research area is spider peptide conserved structure function sodium channel inhibition antinociception; chronic pain; neurological diseases; optimization; peptide engineering; rational design; sodium channel; spider peptide; therapy.

Venom peptides are potent and selective modulators of voltage-gated ion channels that regulate neuronal function both in health and in disease. We previously identified the spider venom peptide Tap1a from the Venezuelan tarantula Theraphosa apophysis that targeted multiple voltage-gated sodium and calcium channels in visceral pain pathways and inhibited visceral mechano-sensing neurons contributing to irritable bowel syndrome. In this work, alanine scanning and domain activity anal. revealed Tap1a inhibited sodium channels by binding with nanomolar affinity to the voltage-sensor domain II utilizing conserved structure-function features characteristic of spider peptides belonging to family NaSpTx1. In order to speed up the development of optimized NaV-targeting peptides with greater inhibitory potency and enhanced in vivo activity, we tested the hypothesis that incorporating residues identified from other optimized NaSpTx1 peptides into Tap1a could also optimize its potency for NaVs. Applying this approach, we designed the peptides Tap1a-OPT1 and Tap1a-OPT2 exhibiting significant increased potency for NaV1.1, NaV1.2, NaV1.3, NaV1.6 and NaV1.7 involved in several neurol. disorders including acute and chronic pain, motor neuron disease and epilepsy. Tap1a-OPT1 showed increased potency for the off-target NaV1.4, while this off-target activity was absent in Tap1a-OPT2. This enhanced potency arose through a slowed off-rate mechanism. Optimized inhibition of NaV channels observed in vitro translated in vivo, with reversal of nocifensive behaviors in a murine model of NaV-mediated pain also enhanced by Tap1a-OPT. Mol. docking studies suggested that improved interactions within loops 3 and 4, and C-terminal of Tap1a-OPT and the NaV channel voltage-sensor domain II were the main drivers of potency optimization. Overall, the rationally designed peptide Tap1a-OPT displayed new and refined structure-function features which are likely the major contributors to its enhanced bioactive properties observed in vivo. This work contributes to the rapid engineering and optimization of potent spider peptides multi-targeting NaV channels, and the research into novel drugs to treat neurol. diseases.

Frontiers in Molecular Biosciences published new progress about Acute pain. 21829-25-4 belongs to class pyridine-derivatives, name is Dimethyl 2,6-dimethyl-4-(2-nitrophenyl)-1,4-dihydropyridine-3,5-dicarboxylate, and the molecular formula is C17H18N2O6, SDS of cas: 21829-25-4.

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Abuhassan, Qamar published the artcileStructured solubility behaviour in bioequivalent fasted simulated intestinal fluids, Quality Control of 72509-76-3, the main research area is bioequivalent fasted simulated intestinal fluid solubility.

Drug solubility in intestinal fluid is a key parameter controlling absorption after the administration of a solid oral dosage form. To measure solubility in vitro simulated intestinal fluids have been developed, but there are multiple recipes and the optimum is unknown. This situation creates difficulties during drug discovery and development research. A recent study characterised sampled fasted intestinal fluids using a multidimensional approach to derive nine bioequivalent fasted intestinal media that covered over 90% of the compositional variability. These media have been applied in this study to examine the equilibrium solubility of twenty one exemplar drugs (naproxen, indomethacin, phenytoin, zafirlukast, piroxicam, ibuprofen, mefenamic acid, furosemide, aprepitant, carvedilol, tadalafil, dipyridamole, posaconazole, atazanavir, fenofibrate, felodipine, griseofulvin, probucol, paracetamol, acyclovir and carbamazepine) to determine if consistent solubility behavior was present. The bioequivalent media provide in the majority of cases structured solubility behavior that is consistent with physicochem. properties and previous solubility studies. For the acidic drugs (pKa < 6.3) solubility is controlled by media pH, the profile is identical and consistent and the lowest and highest pH media identify the lowest and highest solubility in over 70% of cases. For weakly acidic (pKa > 8), basic and neutral drugs solubility is controlled by a combination of media pH and total amphiphile concentration (TAC), a consistent solubility behavior is evident but with variation related to individual drug interactions within the media. The lowest and highest pH x TAC media identify the lowest and highest solubility in over 78% of cases. A subset of the latter category consisting of neutral and drugs non-ionised in the media pH range have been identified with a very narrow solubility range, indicating that the impact of the simulated intestinal media on their solubility is minimal. Two drugs probucol and atazanavir exhibit unusual behavior. The study indicates that the use of two appropriate bioequivalent fasted intestinal media from the nine will identify in vitro the maximum and min. solubility boundaries for drugs and due to the media derivation this is probably applicable in vivo. These media could be applied during discovery and development activities to provide a solubility range, which would assist placement of the drug within the BCS/DCS and rationalise drug and formulation decisions.

European Journal of Pharmaceutics and Biopharmaceutics published new progress about Absorption. 72509-76-3 belongs to class pyridine-derivatives, name is 3-Ethyl 5-methyl 4-(2,3-dichlorophenyl)-2,6-dimethyl-1,4-dihydropyridine-3,5-dicarboxylate, and the molecular formula is C18H19Cl2NO4, Quality Control of 72509-76-3.

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Yi, Hanxi published the artcileEvaluation of a modified flow-through method for predictive dissolution and in vitro/in vivo correlations of immediate release and extended release formulations, Category: pyridine-derivatives, the main research area is dissolution modified flow predictive method immediate extended release formulation.

The present study evaluated the ability of a modified flow-through method for predicting in vivo performance of immediate release (IR) and extended release (ER) formulations. In vitro dissolution of two model drugs, paracetamol IR tablets and felodipine ER tablets, was investigated under tuned conditions using the modified flow-through method and compared with the compendial quality control (QC) basket method. The in vivo absorption properties of paracetamol IR tablets and felodipine ER tablets were investigated in healthy volunteers. In vitro-in vivo correlation (IVIVC) anal. was performed based on the obtained in vitro and in vivo data. Our results demonstrated that the compendial QC method was not able to reflect in vivo actual absorption, while satisfactory discriminatory power and comparable in vitro dissolution/in vivo absorption were achieved for both paracetamol IR tablets and felodipine ER tablets by the modified flow-through method. This study indicated that the modified flow-through method is a potential tool to reflect in vivo performance of the IR and ER formulations.

Journal of Nanomaterials published new progress about Absorption. 72509-76-3 belongs to class pyridine-derivatives, name is 3-Ethyl 5-methyl 4-(2,3-dichlorophenyl)-2,6-dimethyl-1,4-dihydropyridine-3,5-dicarboxylate, and the molecular formula is C18H19Cl2NO4, Category: pyridine-derivatives.

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Asano, Satoshi published the artcileA new intestinal model for analysis of drug absorption and interactions considering physiological translocation of contents, Application of 3-Ethyl 5-methyl 4-(2,3-dichlorophenyl)-2,6-dimethyl-1,4-dihydropyridine-3,5-dicarboxylate, the main research area is midazolam drug absorption interaction intestinal model pharmacotherapy.

Precise prediction of drug absorption is key to the success of new drug development and efficacious pharmacotherapy. In this study, we developed a new absorption model, the advanced translocation model (ATOM), by extending our previous model, the translocation model. ATOM reproduces the translocation of a substance in the intestinal lumen using a partial differential equation with variable dispersion and convection terms to describe natural flow and micromixing within the intestine under not only fasted but also fed conditions. In comparison with ATOM, it was suggested that a conventional absorption model, advanced compartmental absorption and transit model, tends to underestimate micromixing in the upper intestine, and it is difficult to adequately describe movements under the fasted and fed conditions. ATOM explains the observed nonlinear absorption of midazolam successfully, with a minimal number of scaling factors. Furthermore, ATOM considers the apical and basolateral membrane permeabilities of enterocytes sep. and assumes compartmentation of the lamina propria, including blood vessels, to consider intestinal blood flow appropriately. ATOM estimates changes in the intestinal availability caused by drug interaction associated with inhibition of CYP3A and P-glycoprotein in the intestine. Addnl., ATOM can estimate the drug absorption in the fed state considering delayed intestinal drug flow. Therefore, ATOM is a useful tool for the anal. of local pharmacokinetics in the gastrointestinal tract, especially for the estimation of nonlinear drug absorption, which may involve various interactions with intestinal contents or other drugs.

Drug Metabolism & Disposition published new progress about Absorption. 72509-76-3 belongs to class pyridine-derivatives, name is 3-Ethyl 5-methyl 4-(2,3-dichlorophenyl)-2,6-dimethyl-1,4-dihydropyridine-3,5-dicarboxylate, and the molecular formula is C18H19Cl2NO4, Application of 3-Ethyl 5-methyl 4-(2,3-dichlorophenyl)-2,6-dimethyl-1,4-dihydropyridine-3,5-dicarboxylate.

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Ismail, Mai S. published the artcileDevelopment and assessment of oral nifedipine colloidal provesicles, Name: Dimethyl 2,6-dimethyl-4-(2-nitrophenyl)-1,4-dihydropyridine-3,5-dicarboxylate, the main research area is review nifedipine colloidal provesicle assessment development.

Nifedipine(NIF), a well-known calcium channel blocker, is used in the management of hypertension especially if concomitant with kidney, heart or hormonal disorders in children. Colloidal vesicular systems were reported to improve oral absorption and bioavailability of hydrophobic drugs, so the current work embodies a new type of liquid oral colloidal provesicular nano-carrier of NIF. It was developed by simple slurry method. The optimum composition of appropriate lipid film, the effect of surfactant HLB values and cholesterol level on the entrapment efficiency of NIF within liberated vesicles were studied. Addnl., investigating the effect of both initial amount of NIF and the total lipid contents on NIF vesicular entrapment and drug loading were assessed. The morphol. and particle size of both provesicles and liberated nano-vesicles were estimated microscopically and by TEM. The study revealed that 300μmol total lipids of Span 20 /cholesterol at (9:1) molar ratio is an optimum lipid film for higher NIF encapsulation. The vesicular size attained was 209 nm and 79% EE. The in-vitro release study at pH 6.8 revealed an extended release pattern controlling both the release rate and extent. Furthermore, The DSC study showed The successful of intercalating NIF within the vesicle bilayer. This indicate the ability of these provesicles to load NIF successfully.

World Journal of Pharmacy and Pharmaceutical Sciences published new progress about Absorption. 21829-25-4 belongs to class pyridine-derivatives, name is Dimethyl 2,6-dimethyl-4-(2-nitrophenyl)-1,4-dihydropyridine-3,5-dicarboxylate, and the molecular formula is C17H18N2O6, Name: Dimethyl 2,6-dimethyl-4-(2-nitrophenyl)-1,4-dihydropyridine-3,5-dicarboxylate.

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Tubtimsri, Sukannika published the artcileImprovement in Solubility and Absorption of Nifedipine Using Solid Solution: Correlations between Surface Free Energy and Drug Dissolution, COA of Formula: C17H18N2O6, the main research area is nifedipine absorption solubility surface free energy drug dissolution correlation; nifedipine; polysorbate; poorly water-soluble drug; solid solution; third generation solid dispersion.

Ternary solid solutions composed of nifedipine (NDP), amino methacrylate copolymer (AMCP), and polysorbate (PS) 20, 60, or 65 were prepared using a solvent evaporation method. The dissolution profiles of NDP were used to study the effect of the addition of polysorbate based on hydrophilic properties. A solid solution of NDP and AMCP was recently developed; however, the dissolution of NDP was <70%. In the present study, polysorbate was added to improve the dissolution of the drug by altering its hydrophilicity. The suitable formulation contained NDP and AMCP at a ratio of 1:4 and polysorbate at a concentration of 0.1%, 0.3%, or 0.6%. Differential scanning calorimetry and powder X-ray diffraction were used to examine the solid solutions No peak representing crystalline NDP was observed in any solid solution samples, suggesting that the drug was molecularly dispersed in AMCP. The NDP dissolution from NDP powder and solid solution without PS were 16.82% and 58.19%, resp. The highest dissolution of NDP of approx. 95.25% was noted at 120 min for the formulation containing 0.6% PS20. Linear correlations were observed between the surface free energy and percentages of dissolved NDP (R2 = 0.7115-0.9315). Cellular uptake across Caco-2 was selected to determine the drug permeability. The percentages of cellular uptake from the NDP powder, solid solution without and with PS20 were 0.25%, 3.60%, and 7.27%, resp. Polymers (Basel, Switzerland) published new progress about Absorption. 21829-25-4 belongs to class pyridine-derivatives, name is Dimethyl 2,6-dimethyl-4-(2-nitrophenyl)-1,4-dihydropyridine-3,5-dicarboxylate, and the molecular formula is C17H18N2O6, COA of Formula: C17H18N2O6.

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Nakanishi, Atsushi published the artcileSpectral imaging of pharmaceutical materials with a compact terahertz difference-frequency generation semiconductor source, Application of Dimethyl 2,6-dimethyl-4-(2-nitrophenyl)-1,4-dihydropyridine-3,5-dicarboxylate, the main research area is pharmaceutical material spectral imaging terahertz frequency generation semiconductor.

Spectral imaging of pharmaceutical material using a compact ultra-broadband (1-4 THz) terahertz semiconductor source was demonstrated. False-color RGB images could be obtained using a simple procedure (calibration free). The ability to distinguish the polymorphism of carbamazepine (CBZ), the hydrate forms of D-(+)-glucose and caffeine, and the crystallinity of nifedipine was demonstrated using the THz DFG source. Crystal forms of pharmaceutical materials can be distinguished using this method.

Analytical Methods published new progress about Absorption. 21829-25-4 belongs to class pyridine-derivatives, name is Dimethyl 2,6-dimethyl-4-(2-nitrophenyl)-1,4-dihydropyridine-3,5-dicarboxylate, and the molecular formula is C17H18N2O6, Application of Dimethyl 2,6-dimethyl-4-(2-nitrophenyl)-1,4-dihydropyridine-3,5-dicarboxylate.

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Hedge, Oliver J. published the artcileInvestigation of Self-Emulsifying Drug-Delivery System Interaction with a Biomimetic Membrane under Conditions Relevant to the Small Intestine, Safety of 3-Ethyl 5-methyl 4-(2,3-dichlorophenyl)-2,6-dimethyl-1,4-dihydropyridine-3,5-dicarboxylate, the main research area is small intestine self emulsifying drug delivery system biomimetic membrane.

Self-emulsifying drug-delivery systems (SEDDS) have been extensively shown to increase oral absorption of solvation-limited compounds However, there has been little clin. and com. use of these formulations, in large part because the demonstrated advantages of SEDDS have been outweighed by our inability to precisely predict drug absorption from SEDDS using current in vitro assays. To overcome this limitation and increase the biol. relevancy of in vitro assays, an absorption function can be incorporated using biomimetic membranes. However, the effects that SEDDS have on the integrity of a biomimetic membrane are not known. In this study, a quartz crystal microbalance with dissipation monitoring and total internal reflection fluorescence microscopy were employed as complementary methods to in vitro lipolysis-permeation assays to characterize the interaction of various actively digested SEDDS with a liquescent artificial membrane comprising lecithin in dodecane (LiDo). Observations from surface anal. showed that interactions between the digesting SEDDS and LiDo membrane coincided with inflection points in the digestion profiles. Importantly, no indications of membrane damage could be observed, which was supported by flux profiles of the lipophilic model drug felodipine (FEL) and impermeable marker Lucifer yellow on the basal side of the membrane. There was a correlation between the digestion kinetics of the SEDDS and the flux of FEL, but no clear correlation between solubilization and absorption profiles. Membrane interactions were dependent on the composition of lipids within each SEDDS, with the more digestible lipids leading to more pronounced interactions, but in all cases, the integrity of the membrane was maintained. These insights demonstrate that LiDo membranes are compatible with in vitro lipolysis assays for improving predictions of drug absorption from lipid-based formulations.

Langmuir published new progress about Absorption. 72509-76-3 belongs to class pyridine-derivatives, name is 3-Ethyl 5-methyl 4-(2,3-dichlorophenyl)-2,6-dimethyl-1,4-dihydropyridine-3,5-dicarboxylate, and the molecular formula is C18H19Cl2NO4, Safety of 3-Ethyl 5-methyl 4-(2,3-dichlorophenyl)-2,6-dimethyl-1,4-dihydropyridine-3,5-dicarboxylate.

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Premkumar, B. published the artcileFormulation and evaluation of Felodipine hollow microspheres, Application of 3-Ethyl 5-methyl 4-(2,3-dichlorophenyl)-2,6-dimethyl-1,4-dihydropyridine-3,5-dicarboxylate, the main research area is blood pressure heart stroke felodipine hollow microsphere biocompatibility stability.

Felodipine is a calcium channel blocker which is used for the treatment of high blood pressure to prevent heart stroke. In the current research work hollow microspheres of Felodipine with better absorption in gastric pH was formulated by using various polymers. Drug polymer compatibility was characterized by FT-IR. Microspheres were prepared by emulsion solvent diffusion technique by using different polymers such as Et cellulose, carbopol 934, eudragit and sodium alginate at varying concentrations The formulations were evaluated for micromeritic properties, buoyancy, percentage yield, entrapment efficiency, in vitro studies and stability stuides. SEM photographs showed outer surface of microspheres was smooth and dense where as internal surface was porous which helped to prolong floating. Optimized F2 formulation exhibited higher release rate 95.55%. In vitro drug release studies showed controlled release of Felodipine for over 8h. Stability studies indicated the F2 formulation was stable with respect to its drug release.

European Journal of Biomedical and Pharmaceutical Sciences published new progress about Absorption. 72509-76-3 belongs to class pyridine-derivatives, name is 3-Ethyl 5-methyl 4-(2,3-dichlorophenyl)-2,6-dimethyl-1,4-dihydropyridine-3,5-dicarboxylate, and the molecular formula is C18H19Cl2NO4, Application of 3-Ethyl 5-methyl 4-(2,3-dichlorophenyl)-2,6-dimethyl-1,4-dihydropyridine-3,5-dicarboxylate.

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Bi, Ye published the artcileA liposomal formulation for improving solubility and oral bioavailability of nifedipine, COA of Formula: C17H18N2O6, the main research area is nifedipine liposome oral drug delivery formulation controlled release bioavailability; bioavailability; nifedipine; pharmacokinetics; proliposomes.

Proliposomes were used to improve the solubility and oral bioavailability of nifedipine. Nifedipine proliposomes were prepared by methanol injection-spray drying method. The response surface method was used to optimize formulation to enhance the encapsulation efficiency (EE%) of nifedipine. The particle size of nifedipine proliposomes after rehydration was 114 nm. Surface morphol. of nifedipine proliposomes was observed by a scanning electron microscope (SEM) and interaction of formulation ingredients was assessed by differential scanning calorimetry (DSC). The solubility of nifedipine is improved 24.8 times after forming proliposomes. In vitro release experiment, nifedipine proliposomes had a control release effect, especially in simulated gastric fluid. In vivo, nifedipine proliposomes significantly improved the bioavailability of nifedipine. The area under the concentration-time curve (AUC0-âˆ? of nifedipine proliposomes was about 10 times than nifedipine after oral administration. The elimination half-life (T1/2β) of nifedipine was increased from 1.6 h to 6.6 h. In conclusion, proliposomes was a promising system to deliver nifedipine through oral route and warranted further investigation.

Molecules published new progress about Absorption. 21829-25-4 belongs to class pyridine-derivatives, name is Dimethyl 2,6-dimethyl-4-(2-nitrophenyl)-1,4-dihydropyridine-3,5-dicarboxylate, and the molecular formula is C17H18N2O6, COA of Formula: C17H18N2O6.

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem