Reference Preparation Research Articles

Pharmacokinetics and safety of the two oral cefaclor formulations in healthy chinese subjects in the fasting and postprandial states.

We conducted a phase I bioequivalence trial in healthy Chinese subjects in the fasting and postprandial states. The goal of this trial was to compare the pharmacokinetics and safety of the test preparation Cefaclor granule (Disha Pharmaceutical Group Co., Ltd.) and the reference preparation Cefaclor suspension (Ceclor®, Eli Lilly and Company). In this trial, 24 subjects were selected in the fasting and postprandial states, respectively. Enrolled subjects randomly accepted a single dose of 0.125 g Cefaclor granule or Cefaclor suspension. The washout period was set as 2 days. Blood samples were collected within 8 h after administration in the fasting state and within 10 h after administration in the postprandial state. Plasma concentrations were determined by Liquid chromatography-tandem mass spectrometry (LC-MS/MS). Pharmacokinetic parameters (AUC, Cmax) were used to evaluate bioequivalence of the two drugs. In the fasting trial, the geometric mean ratios (90% confidence intervals CIs) for Cmax, AUC0-t, and AUC0-∞ were 93.01% (85.96%–100.63%), 97.92% (96.49%–99.38%) and 97.95% (96.52%–99.41%), respectively. The GMR (90% CIs) for Cmax, AUC0-t, and AUC0-∞ in postprandial state were 89.27% (81.97%–97.22%), 97.31% (95.98%–98.65%) and 97.31% (95.93%–98.71%), respectively. The 90% CIs of AUC and Cmax in the fasting and postprandial states were within the 80–125% bioequivalence range. Therefore, Cefaclor granule and Cefaclor suspension were bioequivalent and displayed similar safety profiles. Furthermore, food intake affected the pharmacokinetic parameters of both drugs.

PHYTOCHEMICAL AND MICROBIOLOGICAL ASPECTS OF THE <i>NIGELLA SATIVA</i> L. HERBS STUDY

Nigella sativa L. is a promising plant object, herbal medicinal raw materials of which can be comprehensively used for the development of drugs with an antimicrobial activity.The aim of the study was to screen and compare the antimicrobial activity of water-ethanolic extractions from the Nigella sativa L. herbs with a eucalyptus tincture of as a reference preparation.Materials and methods. Chromatograms of the extracts were obtained by thin layer chromatography in the system of chloroform – ethanol – water (26:16:3). The detection of adsorption zones was carried out in daylight, in the UV light at λ=254 nm and λ=365 nm, as well as by treatment with reagents – a 3% alcohol solution of aluminum chloride and a solution of diazobenzosulfonic acid in a 20% sodium carbonate solution. The next step was to determine the minimum inhibitory concentration by the method of double serial dilutions in Mueller-Hinton nutrient broth (Bio-Rad, USA). As test cultures, the strains of the American Type Culture Collection (ATCC) microorganisms were used: Staphylococcus aureus (ATCC 29213), Escherichia coli (ATCC 25922), Pseudomonas aeruginosa (ATCC 27853), as well as Candida albicans (a clinical strain). Simultaneously, an experiment to establish a “negative” control was carried out. For the comparative evaluation of the studied samples activity, its activity was compared with the reference preparation with a proven antimicrobial activity – a eucalyptus tincture.Results. For all water-ethanolic extractions and the Nigella sativa L. herb tincture, the adsorption zones characteristic of flavonoids with Rf1 = 0.28, Rf2 = 0.15, Rf3 = 0.11 were revealed, and under the action of an alcoholic solution of aluminum chloride, the fluorescence of the adsorption zones was also enhanced, which indicates the phenolic nature of these compounds.In the course of the study, it was found out that all water-ethanolic extractions from the Nigella sativa L. herbs have the greatest antimicrobial effect against the Pseudomonas aeruginosa strain. When compared with the reference preparation – a eucalyptus tincture, it was notified that the specified tincture of the Nigella sativa L. herbs has an advantage in the antimicrobial activity over the strain of Pseudomonas aeruginosa – the action at the 16-fold dilution vs the 4-fold dilution. The action on the Escherichia coli and Candida albicans strains is comparable for the both tinctures.Conclusion. The obtained results of phytochemical and microbiological analyses will be used as a rationale for the introduction of antimicrobial preparations based on the Nigella sativa herbs in medical and pharmaceutical practice.

Pharmacological characteristics of intranasal dosage forms containing Ginkgo biloba extracts

Background: This article reviews the pharmacological characteristics of developed dosage forms for intranasal administration. The influence of the type of dosage form on the efficacy of the drug is significant. Gel-like structures are interesting objects for research. Interest in understanding the nature and properties of such structures is due to the variety of effects observed when gels are used. The active ingredient in the studied forms is ginkgo biloba extract obtained by ultrasonic extraction followed by thickening. The object of comparison is standardized dried ginkgo biloba extract (EGB 76). The study of cerebrotropic activity of the developed gels was conducted on the model of bilateral occlusion of the common carotid arteries. The studied objects and the reference preparation were administered therapeutically after modeling cerebral ischemia once a day for 3 weeks. Aim of the study: To evaluate specific pharmacological activity of the developed dosage forms of ginkgo biloba. Materials and Methods: Studies were performed in an appropriate design by simulating cerebral ischaemia in rabbits using simultaneous bilateral occlusion of the common carotid arteries. Changes in cerebral blood flow velocity were performed by Doppler using an appropriate transducer and software package. The data obtained were statistically processed using an application software package. Results: Conducted investigations revealed that under conditions of experimental cerebral ischemia simulated by simultaneous occlusion of the common carotid arteries in large laboratory animals (rabbits), the use of the developed dosage forms promoted the reduction of the severity of neurological deficit, the restoration of cerebral hemodynamics and pro/antioxidant balance in the hippocampus. Conclusions: Developed nasal gels based on chitosan and sodium alginate are promising agents for chronic cerebrovascular accident with antioxidant mechanism of action and therapeutic potential similar to oral administration of standardized ginkgo biloba extract - EGB 761

Standardisation of ACPA tests: evaluation of a new candidate reference preparation

IntroductionCommercial assays measuring antibodies to citrullinated protein/peptide (ACPA) show poor quantitative agreement. The diagnostic industry has never adopted the International Union of Immunological Societies-Centers for Disease Control and Prevention (IUIS-CDC)...

Development of Acid-Neutralization and In Vitro Dissolution to Evaluate the Overall Quality of Compound Aluminum Hydroxide Tablets

Background: Compound Aluminum Hydroxide Tablets (CAHTs) are widely used in the Chinese domestic market, and strict quality control is required to ensure their clinical efficacy. Purpose: In this study, we established a comprehensive strategy of acid-neutralization, in vitro dissolution and an assay of magnesium trisilicate to evaluate the overall quality and monitor the consistency of CAHTs. Methods: The acid-neutralization profiles of 38 batches of CAHTs were generated using the dissolution and release method III (the cup method, the Chinese pharmacopeia) combined with potentiometric titration. To directly reflect the disintegration and release process of the preparation, we optimized the sample pretreatment method by omitting the grinding step to determine the profiles of complete tablets. In addition, in vitro dissolution was conducted in the hydrochloric acid medium at pH 1.0 by using the assay of magnesium trisilicate through a validated approach of Flame Atomic Absorption Spectrophotometry (FAAS) to evaluate the similarity of the dissolution profiles. Results: Acid-neutralization tests showed that the quality of the samples from manufacturers B and F was poor. In vitro dissolution experiments showed that the samples from manufacturer A had the highest similarity with the reference preparation, which indicated their good quality consistency. Besides, the optimized acid-neutralization method had the advantage of simple operation and enabled direct characterization of pharmacodynamics in the quality consistency evaluation of antacids. Conclusion: A successful synthetic evaluation strategy was established to assess the overall quality of CAHTs, which demonstrated that the improvement in the quality of this formulation is imperative.

Relative bioavailability study of a generic effervescent tablet formulation of dexketoprofen and thiocolchicoside versus the originator 25 mg film coated tablet (dexketoprofen) and 8 mg capsule (thiocolchicoside)

Aims: The aim of this study was to evaluate the pharmacokinetic profiles and the relative bioavailability of dexketoprofen and thiocolchicoside of the test preparation (dexketoprofen / thiocolchicoside 25 mg / 8 mg effervescent tablet) in comparison with the reference preparations (Keral 25 mg film coated tablet, containing dexketoprofen trometamol equivalent to 25 mg dexketoprofen (Menarini International Operations Luxembourg S.A.) (R1) and Muscoril 8 mg capsule, containing 8 mg thiocolchicoside (Sanofi Aventis İlaçları Ltd. Şti.) (R2) under fasting conditions. Methods: 25 healthy male subjects were enrolled in the study. Volunteers were hospitalised from the evening before drug administration (Day 0) until after the 24-hour blood sampling time on Day 2. Results: 24 subjects completed the study. Relative bioavailability (AUCT/AUCR1) of dexketoprofen from the test preparation was 100.99 %; (AUCT/AUCR2) of 3-O-glucuronide of thiocolchicoside (aglycone) from the test preparation was 100.47 %; (Cmax,T/Cmax,R1) of dexketoprofen from the test preparation was 122.59 %; (Cmax,T/Cmax,R2) of 3-O-glucuronide of thiocolchicoside (aglycone) from the test preparation was 111.43 %. Conclusions: The relative bioavailability AUCT /AUCR of the test preparation compared with both reference preparations is comparable, as shown by the geometric mean ratios of 100.59 % (dexketoprofen) and of 98.20 % (3-O-glucuronide of thiocolchicoside (aglycone).

Bis(2-, 3-, 4-carboxyethylpyridinium) hexafluorosilicates as potential caries prophylactic agents.

Interaction of 2-, 3-, 4-carboxyethylpyridines (L1, L2, L3) with fluorosilicic acid results in the corresponding bis(pyridinium) hexafluorosilicates I-III, characterized by elemental analysis, IR, 1 H, 19 F nuclear magnetic resonance (NMR), and mass spectrometry, solubility data, and X-ray crystallography. Crystallographic data: Fdd2, Z = 8, a = 28.610(2) Å, b = 18.8378(14) Å, c = 7.3236(5) Å (I); P-1, Z = 1, a = 6.2712(4) Å, b = 7.1706(5) Å, c = 10.9721(7) Å, α = 102.514(6)°, β = 97.037(5)°, γ = 93.640(6)° (II); P21 /c, Z = 2, a = 10.0345(6) Å, b = 9.8734(5) Å, c = 9.4704(6) Å, β = 94.347(6)° (III). The dominant intermolecular contacts from the Hirshfeld surface analysis are H… F/F… H, H… H, and H… O/O… H with percentages of 33.3%-34.5%, 26.4%-30.0%, and 16.0%-21.8%. The infrared spectra for I-III exhibit stretching vibrations ν(N+ H) at 3300-3050 cm-1 ; stretching and deformation vibrations ν(SiF) and δ(SiF2 ) for [SiF6 ]2- anions are registered near 740 cm-1 and in the range of 480-440 cm-1 . In the 19 F NMR spectra of aqueous solutions of I-III, strong singlet signals of the [SiF6 ]2- anion were registered at δ(F) = -133.35 ppm (I), -131.43 ppm (II), -129.02 ppm (III) with two satellites due to the spin-spin interaction 29 Si-19 F (J(29 Si-19 F) = 107.5 Hz (II), 107.6 Hz (III)). I-III reveal high solubility in water and dimethyl sulfoxide and very poor solubility in methanol and ethanol. All compounds demonstrate noticeable anticaries activity and absence of hepatotoxic effects, and bis(3-carboxyethylpyridinium) hexafluorosilicate II displays the highest caries-preventive efficacy, which significantly exceeds values for the reference preparations, NaF and (NH4 )2 [SiF6 ].

Development of an in-house reference standard for anti-rabies immunoglobulin potency, to be used in the virus neutralisation test in a Vero cell culture

The development and use of new methods of quality control of medicines involve the use of a lot of reference materials in quality control testing. Specialists of the Russian Research Antiplague Institute “Microbe” have proposed an alternative methodological approach to determination of potency of anti-rabies immunoglobulin in cell culture, which requires the development of an in-house reference standard (RS) certified against the biological reference preparation (BRP) of the European Pharmacopoeia human rabies immunoglobulin. The aim of the study was to develop and evaluate the metrological characteristics of an in-house RS for anti-rabies immunoglobulin potency, to be used in the virus neutralisation test in a Vero cell culture. Materials and methods: The following materials were used in the study: equine rabies immunoglobulin, Vero continuous cell culture, fixed rabies virus (Moscow 3253Vero strain), human rabies immunoglobulin BRP of the European Pharmacopoeia. The potencies of the candidate in-house RS and rabies immunoglobulin samples were determined in the neutralisation test in cell culture. The results were recorded using a fluorescent microscope. Statistical processing was carried out in accordance with general chapter 1.1.0014.15 of the State Pharmacopoeia of the Russian Federation, 14th edition. Results: the certified value of the in-house RS potency was 180.8±18.8 IU/mL. The confidence limits were determined at the 0.95 probability level. The shelf life of the in-house RS is 1.5 years (when stored according to the sanitary regulation SanPiN 3.3686-21). The certified in-house RS was assigned with the number 41-01-20. A set of technical and operational documentation was developed and approved for the in-house RS. The developed in-house RS can be used for in vitro determination of anti-rabies immunoglobulin potency, expressed in international units, to confirm its compliance with the product specification file. Conclusions: the authors developed an in-house RS for anti-rabies immunoglobulin potency, to be used in the virus neutralisation test in cell culture, certified against the human rabies immunoglobulin BRP of the European Pharmacopoeia.

Bioequivalence and Safety of Levetiracetam Granules and Oral Solution: A Randomized, Single-Dose, 2-Period Crossover Study in Healthy Chinese Volunteers Under a Fasting Condition.

The bioequivalence and safety of levetiracetam granules (test formulation) and oral solution (reference formulation) were evaluated in Chinese healthy volunteers under a fasting condition. A total of 24 subjects randomly received the test or reference formulation at the rate of 1:1. The alternative formulation was administered after a 7-day washout period. The blood samples were collected at designated time points. Liquid chromatography-tandem mass spectrometry was applied to determine the plasma concentrations of levetiracetam. Adverse events were monitored and recorded. The 90% CIs for the geometric mean ratios of maximum plasma concentration, area under the plasma concentration-time curve from time 0 to the last quantifiable concentration, and area under the plasma concentration-time curve from time 0 to infinity between test preparation and reference preparation were 95.5% to 110.7%, 100.2% to 105.3%, and 100.3% to 105.7%, respectively, all within an acceptable bioequivalence range of 80.00% 125.00%. Both test and reference preparations were well tolerated. The trial confirmed that a single dose of 500-mg levetiracetam granules was bioequivalent to oral solution under a fasting condition, and may serve as a new dosage form of levetiracetam for clinical practice.

The Preference of Trigona sp for pollen various plant species in Kawasan Rumah Pangan Lestari

Kawasan Rumah Pangan Lesatri (KRPL) is one of the efforts that can be done to manage food security in the face of climate change. The management of the potential contained in KRPL is by applying Trigona sp honey bee cultivation which is integrated with agricultural land. The success of honey bee cultivation is highly dependent on the availability of feed in the environment. This study aims to determine the preferences of pollen collected by Trigona sp at KRPL. This type of research is a qualitative research with Chi square analysis. The research sample was bee pollen contained in 14 stup. The research was conducted from July-November. Data collection was carried out in October and November by making observations at KRPL with an area of 784 meters then making plant reference preparations that have the potential to be Trigona sp pollen feed in KRPL and comparing reference preparations with pollen preparations in Trigona sp stup. The results of the research at KRPL showed that there were 20 types of plant pollen in KRPL. The results of the descriptive analysis with chi square showed that there was a preference for the type of pollen that was fed to Trigona sp bees with a value of x2h > x2t so that H0 was rejected and Ha was accepted.

MycoSNP: A Portable Workflow for Performing Whole-Genome Sequencing Analysis of Candida auris.

Candida auris is an urgent public health threat characterized by high drug-resistant rates and rapid spread in healthcare settings worldwide. As part of the C. auris response, molecular surveillance has helped public health officials track the global spread and investigate local outbreaks. Here, we describe whole-genome sequencing analysis methods used for routine C. auris molecular surveillance in the United States; methods include reference selection, reference preparation, quality assessment and control of sequencing reads, read alignment, and single-nucleotide polymorphism calling and filtration. We also describe the newly developed pipeline MycoSNP, a portable workflow for performing whole-genome sequencing analysis of fungal organisms including C. auris.

ОЦЕНКА СОРБЦИОННЫХ СВОЙСТВ ГРИБОВ ЧАГА (INONOTUS OBLIQUUS) В ОТНОШЕНИИ КАДМИЯ И СВИНЦА

To reduce the toxic load on the body of animals and the accumulation of heavy metals in livestock products, the use of sorbents of various origins is effective. Natural substances, which, along with sorption, have anticarcinogenic, antimutagenic, immunomodulatory properties and antitoxic activity are of particular interest. Sorption properties of the birch fungus Inonotus obliquus (chaga, or chamfered tinder) with respect to cadmium and lead were determined in an experiment on model solutions in order to assess the possibility of its further use as an enterosorbent to reduce the negative effect of heavy metals on the animal body. Under in vitro conditions, the maximum sorption by chaga from aqueous solutions of lead reached more than 95 % of cadmium – up to 89 %. The natural zeolite of the Shivyrtuiskoye deposit was used as a reference preparation. It has been established that the sorption efficiency of both chaga and shivyrtuin with respect to lead is higher than with respect to cadmium. At the same time, chaga sorbed lead worse than shivyrtuin (by 29.4 %), and cadmium more efficiently (by 28.0 %).

Исследование полисахаридов побегов малины обыкновенной и их сорбционной активности

A comparative study of the water-soluble polysaccharide complex and pectin substances of first and second year shoots of common raspberry. Objective - comparative study and sorption activity of polysaccharides of common raspberry shoots. Materials and methods. The samples for the research were collected in a dark coniferous forest on the territory of the Ilyinsky district of Perm Region. The content of polysaccharide fractions was determined by the modified Dreywood anthrone- sulfurous method. A water-soluble polysaccharide complex and pectin substances were sequentially obtained from different parts of the shoots. The sorption activity was determined by the ability of the substances to bind methylene blue, which is a marker for most medical sorbents. The acute toxicity of the obtained polysaccharide fractions was examined according to Prozorovsky V.V. Results. The shoots of the first and second year of common raspberry accumulate more pectin substances than water-soluble polysaccharides. Leaves of raspberry contain more polysaccharides compared to leafless parts. As a result of acute toxicity study, it was found that all studied substances can be classified as low-toxic (LD50>5,000 mg/kg). It was found that water-soluble polysaccharide complex obtained from leafless parts of the shoot of the first and second year shows sorption activity reliably higher than that of the reference preparation (Polyphepan). Sorption activity of pectin substances obtained from leaves of the first and second year shoots also exceeds that of the reference preparation. The highest sorption activity is shown by pectin substances of the second year, and the lowest sorption activity by pectin substances of leafless raspberry shoots. Conclusion. The obtained substances are promising for creating modern sorbents based on polysaccharide fractions of the first and second year shoots of common raspberry. Taking into account the simplicity in harvesting and high sorption activity of polysaccharides of the leafless part of the raspberry shoot, not only leaves but also leafless parts of the shoot should be harvested.

Bioequivalence of a Preparation of Tulathromycin in Cattle

Testing the quality of antibacterial pharmaceutical preparations that can be regarded as generic is of utmost importance to ensure sustainable medical practices. Hence, comparative pharmacokinetics studies become necessary. In this trial, a new pharmaceutical preparation of tulathromycin (TTM) was submitted to a bioequivalence test, taking the reference preparation of this macrolide derivative as control i.e., the commercial preparation of TTM containing 100 mg of the drug Pisadrax ® , manufactured by PiSA Agropacuaria S.A. de C.V. and the reference brand of TTM Draxxin ® (Zoetis, Mexico). Twenty-four young steers Charolais/Brahman randomly divided into two groups of twelve animals each, received a single injection of 2.5 mg/kg subcutaneously of either preparation. A validated HPLC-masses analytical technique of plasma concentrations of tulathromycin was used to determine TTM plasma concentrations at fixed intervals for 240 h. The key pharmacokinetic parameters were obtained by compartmental and non-compartmental analysis. Results show that the experimental preparation of tulathromycin (Pisadrax ® ) can be regarded as bioequivalent to the reference one (Draxxin ® ) in steers, given that AUC0-240, MRT, and K½el values from both preparations resulted statistically indistinguishable and with confidence interval > 95%.

Antimicrobial properties of the new combined dental gel

Given the role of the microbial factor in the development of infectious-inflammatory processes in the oral mucosa, the research aim was to study the antimicrobial action of a new combined dental gel containing Rotocan® (10%) and triclosan (0.4%) in vitro and in the traumatic stomatitis in albino rats. Rotrin- Denta® exhibited strong antimicrobial activity against etalon strains of gram-positive (S. aureus ATTC 6538, S. pyogenes DICK 1, B. subtilis ATCC 6633) and gramnegative (E. coli ATCC 25922) bacteria, which exceeded the action of the reference drug Camident-Zdorovia® and weak effects on pseudomonads (P. aeruginosa ATCC 27853) and fungi (C. albicans CCV 885-653), which is less to the reference preparation. Rotrin- Denta® reduced microbial insemination and eliminated oral dysbiosis in albino rats with traumatic stomatitis, exceeding the effect of Kamident-Zdorov’ya®. The results open up the prospect of its clinical testing and further implementation in the dentistry practice.

Comparative efficacy of transdermal forms for alopecia therapy

Introduction. Alopecia is a polyetiological disorder characterized by hair loss and reducing their number per unit area. Baldness causes psychological and social discomfort to patients, in connection with what an important task is to develop formulations that are more effective than the reference agents.Aim. Investigate the possibility of applying the original substance Y in several dosage forms for the treatment of alopecia in comparison with reference drugs: minoxidil and burdock oil.Materials and methods. The research subject was the original substance Y, for which several dosage forms were made: gel, alcohol and oil compositions. The study on the effectiveness and safety of the developed formulations was carried out on 9 groups of male C57BL/6 mice. Depilation with further assessment of the percentage of hair follicles in the growth and resting phases was tested as a pre-clinical model of alopecia. In the study of the mechanism of action of substance Y, chemiluminescent assay was performed compared with natural antioxidant quercetin in the system luminol – 2,2'-azo-bis(2-amidinopropane)dihydrochloride, in potassium-phosphate buffer medium (pH = 7.4). Statistical processing of the results was carried out using two-way ANOVA using GraphPad Prism 8.0.2, USA software at the level of statistical significance of differences p < 0.05 and p < 0.005.Results and discussion. Based on the results of histological analysis and visual changes, it was found that the effectiveness of the topical forms of substance Y decreases in the following order: gel, alcohol form, oil composition. The use of a combination of the gel base with the test substance Y resulted to the appearance of a larger number of hair follicles in the growth phase than when using the reference preparation – 2 % minoxidil solution (the differences are statistically significant). Chemiluminescent assessment of antioxidant activity showed the lack of antioxidant effect in substance Y.Conclusion. The study combines two pharmaceutical profiles: technological and pharmacological. In the course of the experiments, the prospects of the gel form of the original substance Y for topical therapy of alopecia were shown. In the near future, it is planned to study the mechanism of action of substance Y, as well as registration of patent protection for a new drug.

LIPID COMPLEX FROM THE BROWN SEAWEED SARGASSUM PALLIDUM (TURNER) C. AGARDH AS A HYPOLIPIDEMIC AND ANTIOXIDANT AGENT FOR A HIGH FAT DIET IN EXPERIMENT

The object of the present study was a lipid complex isolated from the thallus of the brown seaweed Sargassum pallidum (Turner) C. Agardh (Sargassum pallidum). The lipid complex of S. pallidum included glycolipids in an amount of 35.1%, neutral lipids – 26.4%, phospholipids – 8.4%, as well as photosynthetic pigments – 30.1% of the total lipids. The content of polyunsaturated fatty acids (PUFAs) was 63.5% of the total fatty acids, of which PUFAs of the n-6 family prevailed (46.5%), the amount of PUFAs of the n-3 family was 17%. Under conditions of fat load, the effect of the lipid complex of S. pallidum and the reference drug Omega-3 on the parameters of lipid metabolism and antioxidant protection in the blood plasma and liver of rats was studied. The fat load was carried out by feeding the animals for 30 days with a standard vivary diet with the addition of 2% cholesterol and 20% beef tallow of the total formulation. The addition of the S. pallidum lipid complex (1 g/kg of body weight) to the fat diet had a hypolipidemic effect, which manifested in the restoration of weight characteristics (body and specific liver’s weight), parameters of liver lipid metabolism (cholesterol, triacylglycerols, free fatty acids), esterifying function of the liver, as well as the content of lipoproteins in the blood plasma. The combined action of n-3 and n-6 PUFAs in the lipid complex of S. pallidum promoted the induction of enzymes of the glutathione circle, providing the antioxidant defense system of the organism. The lipid complex of the brown seaweed S. pallidum was not inferior to the reference preparation Omega-3 in restoration of lipid metabolism and antioxidant defense system of animals on a high-fat diet, and even surpassed that in some parameters.

Long-Term Humoral Immune Response against SARS-CoV-2 after Natural Infection and Subsequent Vaccination According to WHO International Binding Antibody Units (BAU/mL).

The new WHO reference standard allows for the definition of serum antibodies against various SARS-CoV-2 antigens in terms of binding antibody units (BAU/mL) and thus to compare the results of different ELISA systems. In this study, the concentration of antibodies (ABs) against both the S- and the N-protein of SARS-CoV-2 as well as serum neutralization activity were evaluated in three patients after a mild course of COVID-19. Serum samples were collected frequently during a period of over one year. Furthermore, in two individuals, the effects of an additional vaccination with a mRNA vaccine containing the S1-RBD sequence on these antibodies were examined. After natural infection, the antibodies (IgA, IgG) against the S1-protein remained elevated above the established cut-off to positivity (S-IgA 60 BAU/mL and S-IgG 50 BAU/mL, respectively) for over a year in all patients, while this was not the case for ABs against the N-protein (cut-off N-IgG 40 BAU/mL, N-IgA 256 BAU/mL). Sera from all patients retained the ability to neutralize SARS-CoV-2 for more than a year. Vaccination resulted in a rapid boost of antibodies to S1-protein but, as expected, not to the N-protein. Most likely, the wide use of the WHO reference preparation will be very useful in determining the individual immune status of patients after an infection with SARS-CoV-2 or after vaccination.

Bioequivalence of cefalexin in healthy Chinese subjects.

An earlier three-way crossover study evaluating bioequivalence of 3 cefalexin formulations (capsule for reference, capsule and tablet for test) in healthy subjects in Malaysia showed that the intra-individual coefficients of variation were 9.25% for AUC0-t, 9.54% for AUC0-∞, and 13.90% for Cmax. It is preliminarily stated that cefalexin is not a high-variation product. The here-presented clinical study in China was carried out to analyze the pharmacokinetic properties of two preparations in fasting and postprandial condition to assess the bioequivalence of the test preparation and reference preparation when administered on a fasting and postprandial basis in healthy Chinese subjects and to observe the safety of the test preparation and reference preparation in healthy Chinese subjects. In this trial, a total of 56 eligible subjects were randomly assigned to the fasting group and the postprandial group. The two groups were given 250 mg of the test and reference preparation, respectively. Liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) was applied to determine the plasma concentration of cefalexin. PhoenixWinNonlin software (V7.0) was used to calculate the pharmacokinetic parameters of cefalexin using the non-compartmental model (NCA), and the bioequivalence and safety results were calculated by SAS (V9.4) software. The main pharmacokinetic parameters of the test and reference preparations were as follows, the fasting group: Cmax 12.59 ± 2.65 μg/mL, 12.72 ± 2.28 μg/mL; AUC0-8h 20.43 ± 3.47 h×μg/mL, 20.66 ± 3.38 h×μg/mL; AUC0-∞ 20.77 ± 3.53 h×μg/mL, 21.02 ± 3.45 h×μg/mL; the postprandial group: Cmax 5.25 ± 0.94 μg/mL, 5.23 ± 0.80 μg/mL; AUC0-10h 16.92 ± 2.03 h×μg/mL, 17.09 ± 2.31 h×μg/mL; AUC0-∞ 17.33 ± 2.09 h×μg/mL, 17.67 ± 2.45h×μg/mL. The 90% confidence intervals of geometric mean ratios of test preparation and reference preparation were calculated, and the 90% confidence intervals of geometric mean ratios of Cmax, AUC0-10h, and AUC0-∞ were within the 80.00% ~ 125.00% range in both groups. Both Cmax and AUC met the pre-determined criteria for assuming bioequivalence. The test and reference products were bioequivalent after administration under fasting as well as under fed conditions in healthy Chinese subjects. This study may suggest that successful generic versions of cefalexin not only guarantee the market supply of such drugs but can also improve the safety and effectiveness and quality controllability of cefalexin through a new process and a new drug composition ratio.

Conducting Polymers and Photocatalysis: A Mini Review on Selected Conducting Polymers and Photocatalysts as TiO2 and ZnO

: This work covers a comprehensive mini review of the recent studies on the use of composites consisting of conducting polymers coupled with photocatalysts. The selected photocatalysts were TiO2 and ZnO and conducting polymers were polyaniline, polypyrrole and polythiophene. Based on the reference studies, preparation and characterization methodologies were presented along with reaction conditions. Assessment of photocatalytic performance of the composites was based on i. light intensity, band gap energy and effective wavelength region, ii. surface area and initial adsorption, iii. zeta potential and the pH of point of zero charges (pHzpc), with respect to selected substrate physicochemical properties. Conclusive remarks covered recommendations for future studies to fulfill the misconceptions.