Coherent Anti-Stokes Raman Scattering Measurements of Time and Length Scales of Temperature Fluctuations in a Turbulent Flame.

The ability to derive temporal and spatial scales of "instantaneous" local temperature variations in a turbulent flame by means of coherent anti-Stokes Raman scattering (CARS) spectroscopy is demonstrated, for the first time to our knowledge. The measurements employed two CARS spectrometers with synchronized nanosecond pulse-repetitive lasers. The system was enabling to record, with a high temporal resolution of about 10 ns, series of single laser shot CARS spectra of N2 molecules from two spatially overlapped or displaced probe volumes as small as 0.03 × 0.03 × 2 mm3. The spectra were being recorded at a variable delay between two sequential shots, following each other in pairs at a repetition rate of 10 Hz. The series of 500 coupled measurements, at the delays in the range 1 µs-10 ms and the displacements up to 2.5 mm, have been performed in a few points of an open premixed methane-air flame of a laboratory burner with the time-averaged temperatures in the range 1200-1800 K. From the spectra, "instantaneous" temperatures, at the given delay and probe volume distance, have been derived. This allowed the auto-correlation coefficients of temperature fluctuations versus the delay and the displacement to be calculated. These dependences enabled to evaluate temperature correlation times and lengths under various mixture flow rates and equivalence ratios.

Affinity Capture Elution (ACE) ELISA Method Development and Validation for Novel RPH-104 Drug Immunogenicity Evaluation.

As the number of therapeutic protein products is growing rapidly, there is a strong need for the development of bioanalytical methods that are easy to perform, specific, sensitive, robust, and affordable. Methods for immunogenicity evaluation of therapeutic proteins take an important place in this field of bioanalytics. The aim of the study was to develop a method for immunogenicity testing of the novel RPH-104 drug using the Affinity Capture Elution (ACE) ELISA technique. RPH-104 is a promising Interleukin-1 (IL-1) inhibitor that is currently undergoing a series of clinical studies, including those on socially significant and orphan diseases. The developed method was validated for assay cut-point, sensitivity, selectivity, drug tolerance, hook effect, specificity, precision, and stability. Method sensitivity was established at 114.9 ng/mL, while low and high positive controls were equal to anti-RPH-104 antibody concentrations of 155 ng/mL and 2500 ng/mL, respectively. Method specificity was confirmed in the presence of the interfering compounds, namely IL-1α, IL-1ß, and IL1-Ra. The developed and validated ELISA method was successfully applied to subject samples.

A Use of Tritium-Labeled Peat Fulvic Acids and Polyphenolic Derivatives for Designing Pharmacokinetic Experiments on Mice.

Natural products (e.g., polyphenols) have been used as biologically active compounds for centuries. Still, the mechanisms of biological activity of these multicomponent systems are poorly understood due to a lack of appropriate experimental techniques. The method of tritium thermal bombardment allows for non-selective labeling and tracking of all components of complex natural systems. In this study, we applied it to label two well-characterized polyphenolic compounds, peat fulvic acid (FA-Vi18) and oxidized lignin derivative (BP-Cx-1), of predominantly hydrophilic and hydrophobic character, respectively. The identity of the labeled samples was confirmed using size exclusion chromatography. Using ultra-high resolution Fourier transform ion cyclotron resonance mass spectrometry (FT ICR MS), key differences in the molecular composition of BP-Cx-1 and FA-Vi18 were revealed. The labeled samples ([3H]-FA-Vi18 (10 mg/kg) and [3H]-BP-Cx-1 (100 mg/kg)) were administered to female BALB/c mice intravenously (i.v.) and orally. The label distribution was assessed in blood, liver, kidneys, brain, spleen, thymus, ovaries, and heart using liquid scintillation counting. Tritium label was found in all organs studied at different concentrations. For the fulvic acid sample, the largest accumulation was observed in the kidney (Cmax 28.5 mg/kg and 5.6 mg/kg, respectively) for both routes. The organs of preferential accumulation of the lignin derivative were the liver (Cmax accounted for 396.7 and 16.13 mg/kg for i.v. and p.o. routes, respectively) and kidney (Cmax accounted for 343.3 and 17.73 mg/kg for i.v. and p.o. routes, respectively). Our results demonstrate that using the tritium labeling technique enabled successful pharmacokinetic studies on polyphenolic drugs with very different molecular compositions. It proved to be efficient for tissue distribution studies. It was also shown that the dosage of the polyphenolic drug might be lower than 10 mg/kg due to the sensitivity of the 3H detection technique.

MicroRNAs as novel biomarkers for rivaroxaban therapeutic drug monitoring.

OBJECTIVES: The aim of this study is to assess micro-RNAs miR-142 and miR-39 as potential biomarkers for drug-monitoring of rivaroxaban among elderly patients with atrial fibrillation. METHODS: The study involved 57 patients with median (ME) age 87 years [80-94 years old] with nonvalvular atrial fibrillation admitted to a multidisciplinary hospital in Moscow. High-performance liquid chromatography with mass-spectrometry detection (HPLC-MS) was carried out to measure rivaroxaban concentrations. Carriership of CYP3A4 and ABCB1 was detected. MiRNA expression levels were measured. The activity of CYP3A4 isoenzyme was measured as the ratio of the concentrations of 6ß-hydroxycortisol and cortisol. RESULTS: The miR-142 expression levels of patients with CC allelic variant polymorphism ABCB1 3435 C>T (rs1045642) were significantly higher compared to CT and TT variants 31.69 ± 1.60 vs. 34.06 ± 1.66 vs. 33.16 ± 1.77 (p=0.021). Carriers of TT allelic variant polymorphism ABCB1 rs4148738 had a higher concentration of the 6-beta-hydroxycortisol in urine compared to CC and CT variants 3,467.35 ± 1,055.53 vs. 3,453.52 ± 1,516.89 vs. 2,593.30 ± 1,172.52 (p=0.029). As for CYP3A4*22, the carriers of CC allelic variant had higher prothrombin time 14.10 ± 2.17 vs. 11.87 ± 0.60 and INR 1.31 ± 0.20 vs. 1.1 ± 0.06 but lower Quick's value 74.52 ± 16.84 vs. 97.55 ± 10.54 (p=0.059). A positive correlation between the Ct miR-142 and the aPTT p=0.019 was noted. Also miR-142 has a correlation with Quick's value p=0.095. There is no statistically significant connection between miR-142 and miR-39 expression levels and the plasma concentration of rivaroxaban (b coefficient=-2.055, SE 3.952, p=0.605 and b coefficient=1.546, SE 9.887, p=0.876 in the linear regression model respectively). CONCLUSIONS: This study has assessed new potential biomarkers for rivaroxaban therapeutic drug monitoring: miR-142 and miR-39.

MicroRNAs as novel biomarkers for rivaroxaban therapeutic drug monitoring.

OBJECTIVES: The aim of this study is to assess micro-RNAs miR-142 and miR-39 as potential biomarkers for drug-monitoring of rivaroxaban among elderly patients with atrial fibrillation. METHODS: The study involved 57 patients with median (ME) age 87 years [80-94 years old] with nonvalvular atrial fibrillation admitted to a multidisciplinary hospital in Moscow. High-performance liquid chromatography with mass-spectrometry detection (HPLC-MS) was carried out to measure rivaroxaban concentrations. Carriership of CYP3A4 and ABCB1 was detected. MiRNA expression levels were measured. The activity of CYP3A4 isoenzyme was measured as the ratio of the concentrations of 6ß-hydroxycortisol and cortisol. RESULTS: The miR-142 expression levels of patients with CC allelic variant polymorphism ABCB1 3435 C>T (rs1045642) were significantly higher compared to CT and TT variants 31.69 ± 1.60 vs. 34.06 ± 1.66 vs. 33.16 ± 1.77 (p=0.021). Carriers of TT allelic variant polymorphism ABCB1 rs4148738 had a higher concentration of the 6-beta-hydroxycortisol in urine compared to CC and CT variants 3,467.35 ± 1,055.53 vs. 3,453.52 ± 1,516.89 vs. 2,593.30 ± 1,172.52 (p=0.029). As for CYP3A4*22, the carriers of CC allelic variant had higher prothrombin time 14.10 ± 2.17 vs. 11.87 ± 0.60 and INR 1.31 ± 0.20 vs. 1.1 ± 0.06 but lower Quick's value 74.52 ± 16.84 vs. 97.55 ± 10.54 (p=0.059). A positive correlation between the Ct miR-142 and the aPTT p=0.019 was noted. Also miR-142 has a correlation with Quick's value p=0.095. There is no statistically significant connection between miR-142 and miR-39 expression levels and the plasma concentration of rivaroxaban (b coefficient=-2.055, SE 3.952, p=0.605 and b coefficient=1.546, SE 9.887, p=0.876 in the linear regression model respectively). CONCLUSIONS: This study has assessed new potential biomarkers for rivaroxaban therapeutic drug monitoring: miR-142 and miR-39.

Study of the Acute Toxicity of a New Dosage Form of Naloxone Hydrochloride for Intranasal Administration.

The experiment was conducted on 10 Wistar rats, male and female, with initial body weight 270-280 g (males) and 250-260 g (females). The drug was administered using a spray cap in 10 doses of 0.1 mg at 45 min intervals. The average cumulative dose of the drug per naloxone hydrochloride was 36.6 mg/kg for males and 39.4 mg/kg for females. The animals were monitored for 2 weeks after the exposure and then euthanized by a gentle decapitation.We noticed that after each drug administration the animals showed a decrease in motor activity. During the observation period there were no animal deaths or signs of abnormalities in their general state or behavior. Beginning on day 7 a significant increase in body weight of the animals was noted in comparison with the initial data. The relative mass of the internal organs of the treated rats remained within the physiological norm.We conclude that naloxone hydrochloride after an intranasal administration at 36.6 mg/kg for males and 39.4 mg/kg for females does not cause death of animals and or have a toxic effect on their general state, does not change their protein metabolism characteristics or the appearance of the internal organs and their mass.

Genotyping and phenotyping of CYP2D6 and CYP3A isoenzymes in patients with alcohol use disorder: correlation with haloperidol plasma concentration.

BACKGROUND: Haloperidol is used for the treatment of alcohol use disorders in patients with signs of alcohol-related psychosis. Haloperidol therapy poses a high risk of adverse drug reactions (ADR). Contradictory data, which include the effects of genetic polymorphisms in genes encoding the elements of haloperidol biotransformation system on haloperidol metabolism rate and plasma drug concentration ratio, are described in patients with different genotypes. The primary objective of this study was to investigate the effects of CYP2D6 and CYP3A5 genetic polymorphisms on haloperidol equilibrium concentration in patients with alcohol use disorder. METHODS: The study included 69 male patients with alcohol use disorder. Genotyping was performed using the allele-specific real-time PCR. CYP2D6 and CYP3A were phenotyped with HPLC-MS using the concentration of endogenous substrate of the enzyme and its urinary metabolites [6-hydroxy-1,2,3,4-tetrahydro-ß-carboline(6-HO-THBC) to pinoline ratio for CYP2D6 and 6-ß-hydroxycortisol to cortisol ratio for CYP3A]. The equilibrium plasma concentration was determined using LC-MS-MS. RESULTS: Results indicated that both C/D indexes and equilibrium concentration levels depend on CYP2D6 genetic polymorphism, but only in patients receiving haloperidol intramuscular injections [0.26 (0.09; 0.48) vs. 0.54 (0.44; 0.74), p=0.037]. CONCLUSIONS: The study demonstrates that CYP2D6 genetic polymorphism (1846G>A) can affect haloperidol concentration levels in patients with alcohol use disorder.

Elucidation of real-time hardening mechanisms of two novel high-strength calcium phosphate bone cements.

Despite the numerous literature data available in the field of calcium phosphate bone cements, the mechanism and kinetics of their hardening, both of which are of great importance for cements application, in most cases, is unknown. In this work, the mechanism and kinetics of hardening of two novel high-strength calcium phosphate bone cements were studied using the energy dispersive X-ray diffraction technique, which allows rapid collection of the patterns. The phase transformations occurring on the setting and hardening processes were monitored in situ. Containing minimal quantity of components, whose mixing leads to the formation of cements with pH close to neutral, the cements under study are simple in handling. The main component of both formulations is tetracalcium phosphate. In both cements, the effect of the addition of high- and low-molecular weight chitosan on phase development and kinetics was investigated in detail. One of the cements has the compressive strength of about 70 MPa, whereas the strength of the other, containing Ca(3)Al(2)O(6), is much higher, about 100 MPa. This latter cement could be regarded as an alternative to the common low-strength bioresorbable brushite cements.