Macrolide and lincosamide resistance of Streptococcus agalactiae in pregnant women in Poland.

Knowing about the antibiotic resistance, serotypes, and virulence-associated genes of Group B Streptococcus for epidemiological and vaccine development is very important. We have determined antimicrobial susceptibility patterns, serotype, and virulence profiles. The antibiotic susceptibility was assessed for a total of 421 Streptococcus agalactiae strains, isolated from pregnant women and neonates. Then, 89 erythromycin and/or clindamycin-resistant strains (82 isolates obtained from pregnant women and seven isolates derived from neonates) were assessed in detail. PCR techniques were used to identify the studied strains, perform serotyping, and assess genes encoding selected virulence factors. Phenotypic and genotypic methods determined the mechanisms of resistance. All tested strains were sensitive to penicillin and levofloxacin. The constitutive MLSB mechanism (78.2%), inducible MLSB mechanism (14.9%), and M phenotype (6.9%) were identified in the macrolide-resistant strains. It was found that macrolide resistance is strongly associated with the presence of the ermB gene and serotype V. FbsA, fbsB, fbsC, scpB, and lmb formed the most recurring pattern of genes among the nine surface proteins whose genes were analysed. A minority (7.9%) of the GBS isolates exhibited resistance to lincosamides and macrolides, or either, including those that comprised the hypervirulent clone ST-17. The representative antibiotic resistance pattern consisted of erythromycin, clindamycin, and tetracycline resistance (71.9%). An increase in the fraction of strains resistant to macrolides and lincosamides indicates the need for monitoring both the susceptibility of these strains and the presence of the ST-17 clone.

A Review of the Biological Activity of Amidrazone Derivatives.

Amidrazones are widely used in chemical synthesis, industry and agriculture. We compiled some of the most important findings on the biological activities of amidrazones described in the years 2010-2022. The data were obtained using the ScienceDirect, Reaxys and Google Scholar search engines with keywords (amidrazone, carbohydrazonamide, carboximidohydrazide, aminoguanidine) and structure strategies. Compounds with significant biological activities were included in the review. The described structures derived from amidrazones include: amidrazone derivatives; aminoguanidine derivatives; complexes obtained using amidrazones as ligands; and some cyclic compounds obtained from amidrazones and/or containing an amidrazone moiety in their structures. This review includes chapters based on compound activities, including: tuberculostatic, antibacterial, antifungal, antiparasitic, antiviral, anti-inflammatory, cytoprotective, and antitumor compounds, as well as furin and acetylocholinesterase inhibitors. Detailed information on the compounds tested in vivo, along the mechanisms of action and toxicity of the selected amidrazone derivatives, are described. We describe examples of compounds that have a chance of becoming drugs due to promising preclinical or clinical research, as well as old drugs with new therapeutic targets (repositioning) which have the potential to be used in the treatment of other diseases. The described examples prove that amidrazone derivatives are a potential source of new therapeutic substances and deserve further research.

Promising Antimicrobial Properties of Bioactive Compounds from Different Honeybee Products.

Bee products have been known for centuries for their versatile healing properties. In recent decades they have become the subject of documented scientific research. This review aims to present and compare the impact of bee products and their components as antimicrobial agents. Honey, propolis, royal jelly and bee venom are bee products that have antibacterial properties. Sensitivity of bacteria to these products varies considerably between products and varieties of the same product depending on their origin. According to the type of bee product, different degrees of activity were observed against Gram-positive and Gram-negative bacteria, yeasts, molds and dermatophytes, as well as biofilm-forming microorganisms. Pseudomonas aeruginosa turned out to be the most resistant to bee products. An analysis of average minimum inhibitory concentration values for bee products showed that bee venom has the strongest bacterial effectiveness, while royal jelly showed the weakest antibacterial activity. The most challenging problems associated with using bee products for medical purposes are dosage and safety. The complexity and variability in composition of these products raise the need for their standardization before safe and predictable clinical uses can be achieved.

Relationship between antibiotic resistance, biofilm formation, genes coding virulence factors and source of origin of Pseudomonas aeruginosa clinical strains.

INTRODUCTION AND OBJECTIVE: Pseudomonas aeruginosa is an opportunistic pathogen that causes difficult with treating infections, especially in the immunocompromised and patients with some underlying disease. The aim of the study is to assess the antibiotic resistance, biofilm formation, and the presence of genes encoding various virulence factors in clinical isolates of P. aeruginosa. MATERIAL AND METHODS: Seventy-three clinical isolates of Pseudomonas aeruginosa were tested. Antimicrobial Susceptibility Testing (AST) and carbapenemases production was performed in accordance with the EUCAST guidelines. The ability to form biofilm was assessed by crystal violet assay. Genes encoding selected virulence factors were detected using standard polymerase chain reaction (PCR). RESULTS: Among the 73 clinical isolates of P. aeruginosa, 41.1% were resistant to imipenem, 61.6% to meropenem, 30.1% to ciprofloxacin and 15.1% to tobramycin. Over 20% of isolates were producers of MBL. Antibiotic resistance profiling revealed that 23.3% of strains were sensitive to all antibiotics, 60.3% were LDR phenotype, and 16.4% were MDR phenotype. The majority of strains (73.6%) were strong-biofilm producers, 17.0% were moderate and 9.4% were weak biofilm producers. PCR analysis showed the presence of lasB, aprE and prpL genes in most of the tested strains (93.1%, 87.7% and 74.0%, respectively). Among strong biofilm producers, 22.2% were MDR, 63.0% of strains represented LDR phenotype, and 14.8% were sensitive to all antibiotics. Moderate and weak biofilm producers were LDR and sensitive phenotypes only (respectively, 58.3% and 42.9 - LDR, 41.7 and 51.7% - sensitive). CONCLUSIONS: High frequency of MDR strains and their ability of biofilm formation and virulence factors may be a threat to effective therapy, and can increase morbidity and mortality of infected patients.

Antibiotic Resistance, Biofilm Formation, and Presence of Genes Encoding Virulence Factors in Strains Isolated from the Pharmaceutical Production Environment.

The spread of bacterial resistance to antibiotics affects various areas of life. The aim of this study was to assess the occurrence of Pseudomonas aeruginosa, and other bacteria mainly from orders Enterobacterales and Staphylococcus in the pharmaceutical production sites, and to characterize isolated strains in the aspects of antibiotic resistance, biofilm formation, and presence of genes encoding virulence factors. Genes encoding selected virulence factors were detected using PCR techniques. Antimicrobial susceptibility testing was applied in accordance with the EUCAST recommendations. A total of 46 P. aeruginosa strains were isolated and 85% strains showed a strong biofilm-forming ability. The qualitative identification of genes taking part in Quorum Sensing system demonstrated that over 89% of strains contained lasR and rhlI genes. An antimicrobial susceptibility testing revealed nine strains resistant to at least one antibiotic, and two isolates were the metallo-ß-lactamase producers. Moreover, the majority of P. aeruginosa strains contained genes encoding various virulence factors. Presence of even low level of pathogenic microorganisms or higher level of opportunistic pathogens and their toxic metabolites might result in the production inefficiency. Therefore, the prevention of microbial contamination, effectiveness of sanitary and hygienic applied protocols, and constant microbiological monitoring of the environment are of great importance.

IMMUNODIAGNOSIS IN MEMBRANOUS NEPHROPATHY.

One of the diseases leading to chronic end-stage renal disease is membranous nephropathy (MN). The main cause of this disease is the formation of antibodies to foreign and native antigens. Membranous nephropathy can be conventionally divided into 2 types: primary form (when the primary disease is unknown) and secondary form. Detection of appropriate antibodies is one of the methods to recognize and differentiate primary and secondary forms. A large role in non-invasive diagnosis of MN and differentiation of the primary form from the secondary play antinuclear antibodies (ANA), antibodies against granulocyte cytoplasm (ANCA), antiglomerular basement antibodies (anti-GBM) and phospholipase A2 receptor antibodies (anti-PLA2R). Differentiation matters when choosing a treatment choice. In the primary form, it is immunosuppression, and in the form of secondary treatment, it consists in curing or controlling diseases that can cause symptoms of MN. The aim: Analysis of serological methods helpful in immunodiagnosis of membranous nephropathy.

HYALURONIC ACID IN ORTHOPEDICS.

Hyaluronic acid (HA) as a compound was discovered in 1934 by Karl Meyer and John Palmer as one of the glycosaminoglycans (GAG) in the vitreous body of the bovine eye. HA occurs naturally in many organs, tissues and body fluids, and especially is presented in large quantities in articular cartilage and synovial fluid. It is a non-protein, non-sulfate glycosaminoglycan which has an important role in the physiological biomechanics of synovial fluid, there is responsible for lubrication and drug-elasticity. In the musculoskeletal system, hyaluronic acid is produced by synoviocytes, fibroblasts and chondrocytes. The concentration of hyaluronic acid decreases not only with age, but also in connection with the progression of certain diseases, for example osteoarthritis (OA). For this reason, it has been used for almost 50 years to try to alleviate and treat symptoms of OA in humans and animals. Numerous studies confirmed the beneficial effect of hyaluronic acid supplementation in OA. Patients which has intraarticular viscosupplementation of HA experience less pain and have a reduced need to take nonsteroidal anti-inflammatory drugs. Intra articular HA administration shows a low risk of local and systemic side effects while maintaining proper administration under aseptic conditions. Nevertheless, local inflammatory reactions occur, but it are most often self-limiting or do not require invasive treatment. The issue of recommending hyaluronic acid in osteoarthritis is still ambiguous and controversial.

Quality of Dietary Supplements Containing Plant-Derived Ingredients Reconsidered by Microbiological Approach.

Dietary supplements cover a wide range of products, the most popular are those containing plant-based ingredients. Supplements are consumed by consumers of all ages as well as by both healthy and sick people. The lack of unified regulation in this sector increases the probability that supplements are poor chemical and microbiological quality and can be dangerous for patients. The aim of this paper is to highlight selected issues associated with the microbiological quality of dietary supplements containing plant materials. We focus on the most recent reports referring to bacterial and fungal contaminations as well as the presence of mycotoxins. Dietary supplements containing plant ingredients commonly show a variety of microbial contaminants, which might be crucial for consumer safety. They often contain microorganisms potentially pathogenic to humans. Metabolites produced by microorganisms may pose a threat to the health of consumers. Because of that, in this review, we emphasize the risk that may be associated with the lack of appropriate studies of the quality of the supplements.

Increasing Resistance and Changes in Distribution of Serotypes of Streptococcus agalactiae in Poland.

Streptococcus agalactiae is responsible for serious infections in newborn babies, pregnant women, and other patients. The aim of this study was to evaluate antimicrobial susceptibility, serotype distribution, and virulence determinants of the S. agalactiae isolates derived from clinical specimens considering the global increase of both antibiotic resistance and virulence. A total of 165 isolates were identified and serotyped by PCR techniques. Antimicrobial susceptibility was assessed by disk diffusion method, gradient diffusion method and VITEK® System. Virulence associated genes were investigated by PCR; ability to form biofilm was assessed using a microtiter plate assay. The highest observed MIC value for penicillin G was 0.12 µg/mL, seen in 8.5% of isolates. Resistance to erythromycin and clindamycin were found in 30.38% and 24.8% of the strains, respectively. The serotype III (32.73%), V (25.45%), and Ia (18.18%) were found as the most frequently represented. Previously unidentified strains in Poland, belonging to serotypes VI (three strains) and VII (one strain) were recognized. The presence of genes encoding various virulence factors as well as diverse ability to form biofilm were found. In conclusion, macrolide-resistance and decreased susceptibility to penicillin G were revealed signifying the increasing resistance among group B streptococci. Moreover, the presence of genes encoding various virulence factors and the ability to form biofilm were confirmed indicating their role in the pathomechanisms of the evaluated GBS infections.

The value of the free androgen index depends on the phenotype of polycystic ovary syndrome - a single-centre experience.

INTRODUCTION: The free androgen index (FAI) values differ among patients with polycystic ovarian syndrome; however, the differences are not fully understood or known. The aim of the study was to evaluate FAI in women with polycystic ovary syndrome (PCOS) in regard to the phenotype of the PCOS and insulin resistance status. MATERIAL AND METHODS: Anthropometric, hormonal, and biochemical parameters were assessed in 312 recruited women with PCOS. The FAI values were calculated in the reproductive and metabolic phenotypes of PCOS in groups of insulin resistance status based on the homeostasis model assessment-insulin resistance (HOMA-IR) > 2.0 or fasting insulin (FI) > 10 mmol/L. To test the relationship between individual variables, Spearman's correlation analysis, the Kolmogorov-Smirnov test, and Student's t-test were used. RESULTS: The correlation between FAI values and HOMA-IR and FI was 0.42 and 0.47, respectively, in PCOS patients. A two fold higher FAI value was observed in metabolic PCOS phenotype when compared to the reproductive one (8.51 ± 5.56 vs. 4.40 ± 2.45 for HOMA-IR and 8.73 ± 6.09 vs. 4.31 ± 3.39 for FI, respectively; p < 0.05). CONCLUSIONS: PCOS patients are not a homogenous group in terms of FAI value. Patients with metabolic PCOS phenotype are characterised by two-fold higher FAI values compared with reproductive PCOS phenotype. Further studies on the metabolic and androgenic status of different types of PCOS phenotypes should be carried out.

Are dietary supplements containing plant-derived ingredients safe microbiologically?

Dietary supplements, particularly those containing ingredients of natural origin, may contain microbiological contaminants, both bacterial and fungal. The present study evaluated the microbiological purity of selected dietary supplements containing plant-based ingredients before their release to the market, as well as raw materials of plant origin which are used in the production of such supplements. A total of 122 samples of supplements and 30 materials of plant origin were studied, with 92.1% exhibiting different degrees of bacterial contamination. Eight samples (5.3%) were contaminated by aerobic bacteria in amounts exceeding 105 CFU/g. Five (3.3%) of the studied supplements were found to contain bacteria from the family Enterobacteriaceae at a level exceeding 103 CFU/g. Furthermore, a considerable proportion of the studied samples (86.8%) contained fungal contamination. Microbiological contamination may contribute to a deterioration in quality and stability of dietary supplements. In addition, high levels of pathogenic bacteria and microorganisms may pose a risk to consumers.

Halloysite nanotubes as carriers of vancomycin in alginate-based wound dressing.

The influence of an inorganic support - halloysite nanotubes - on the release rate and biological activity of the antibiotic encapsulated in alginate-based dressings was studied. The halloysite samples were loaded with approx. 10 wt.% of the antibiotic and then encapsulated in Alginate and Gelatin/Alginate gels. The material functionalized with aliphatic amine significantly extended the release of vancomycin from alginate-based gels as compared to that achieved when silica was used. After 24 h, the released amounts of the antibiotic immobilized at silica reached 70%, while for the drug immobilized at halloysite the released amount of vancomycin reached 44% for Alginate discs. The addition of gelatin resulted in even more prolonged sustained release of the drug. The antibiotic was released from the system with a double barrier with Higuchi kinetic model and Fickian diffusion mechanism. Only the immobilized drug encapsulated in Alginate gel demonstrated very good antimicrobial activity against various bacteria. The inhibition zones were greater than those of the standard discs for the staphylococci and enterococci bacteria tested. The addition of gelatin adversely affected the biological activity of the system. The inhibition zones were smaller than those of the reference samples. A reduction in the drug dose by half had no significant effect on changing the release rate and microbiological activity. The in vivo toxicity studies of the material with immobilized drug were carried out with Acutodesmus acuminatus and Daphnia magna. The material studied had no effect on the living organisms used in the bioassays. The proposed system with a double barrier demonstrated high storage stability.

MICROBIOLOGICAL QUALITY OF FOOD SUPPLEMENTS.

Many specialists note that the food offered today - as a result of very complex technological processing - is devoid of many components that are important for the organism and the shortages have to be supplemented. The simplest for it is to consume diet supplements that provide the missing element in a concentrated form. In accordance with the applicable law, medicinal products include all substances or mixtures of substances that are attributed with properties of preventing or treating diseases with humans or animals. Permits to admit supplements to the market are issued by the Chief Sanitary Inspector and the related authorities; permits for medicines are issued by the Chief Pharmaceutical Inspector and the Office for Registration of Medicinal Products, Medical Devices and Biocidal Products. Therefore, admittance of a supplement to the market is less costly and time consuming_than admittance of a medicine. Supplements and medicines may contain the same component but medicines will have a larger concentration than supplements. Sale of supplements at drug stores and in the form of tablets, capsules, liquids or powders makes consumer often confusing supplements with medicines. Now there are no normative documents specifying limits of microbiological impurities in diet supplements. In Polish legislation, diet supplements are subject to legal acts concerning food. Medicines have to comply with microbiological purity requirements specified in the Polish Pharmacopeia. As evidenced with the completed tests, the proportion of diet supplement samples with microbiological impurities is 6.5%. Sales of diet supplements have been growing each year, they are consumed by healthy people but also people with immunology deficiencies and by children and therefore consumers must be certain that they buy safe products.

Will the use of double barrier result in sustained release of vancomycin? Optimization of parameters for preparation of a new antibacterial alginate-based modern dressing.

The aim of this research was to prepare and characterize an alginate-based wound dressing containing vancomycin immobilized at the silica surface. The silica samples functionalized with amine, diol and carboxylic acid groups were loaded with 7.8, 5.7 and 7.1wt.% of the antibiotic respectively. The immobilized drug was encapsulated in alginate or gelatin/alginate gels and the average concentration of vancomycin was about 10mg per g of the dried gel. The effect of functional organic groups at the silica surface on the release rate of the drug was investigated. Only the drug immobilized at Si-amine in alginate matrix was found to demonstrate slower release from the proposed wound dressing. The in vitro release profiles for other silica carriers did not show significant differences in relation to the free loaded drug. The presence of gelatin had a favourable impact on the slowing down of the drug release from the dressing with a double barrier. All the gels studied with vancomycin immobilized at the silica surface demonstrated antimicrobial activity against various bacteria. A reduction of the drug dose to a half had no effect on changing microbiological activity of gels.

Vancomycin-modified silica: Synthesis, controlled release and biological activity of the drug.

Vancomycin was immobilized on three different organically functionalized silicas. The materials obtained were used for a controlled release of the antibiotic. The influence of the type of chemical bond on the in vitro drug release was investigated. A weak ionic bonding caused burst release of the drug within one day. A covalent bonding resulted in a slowdown in the release process and uniformity of dosage release. For these two carriers, biological activity of the drug was retained because the minimal inhibitory concentration values against the strains tested were similar to that of a free form of the drug (about 2 µg/mL). A strong ionic bonding of vancomycin adversely affected both the drug release, as well as its biological activity. A strong base on the surface of the silica prevented disconnection of the antibiotic which then became ineffective.