Susceptibility Of Microorganisms Research Articles

Prevalence and susceptibility of microorganisms in vaginal isolates

Prevalence and susceptibility of microorganisms in vaginal isolates

The effect of low-intensity laser radiation on the sensitivity of Staphylococcus aureus to some halogen-containing azaheterocycles

The rapid rate of acquisition and spread of resistance to antibiotics by microorganisms leads to the search and investigation of new ways of combating infectious agents. Being a modern, minimally invasive method with an almost complete absence of side effects, the use of low-intensity laser radiation can be considered as one of the alternatives to traditional antibiotic therapy. At the same time, the search for new chemical compounds with pronounced antimicrobial activity is also promising. The impact of low-intensity laser of the red spectrum (λ = 660 nm) on the sensitivity of a clinical isolate of Staphylococcus aureus to newly synthesized halogen- and chalcogen-halogen-containing derivatives of the quinazoline and benzothiazole series was studied using the serial microdilutions method with the determination of minimal inhibitory and minimal bactericidal concentrations. To evaluate the antimicrobial properties of the investigated substances in dynamic, we investigated their activity two months after the synthesis with subsequent comparison to freshly synthesized compounds. The research results indicate that the most pronounced antimicrobial effect was shown by trichlorotelluromethylthiazoloquinazolinium chloride and propargylthiobenzothiazolium hexachlorotellurate. Evaluating the dynamics of the activity of the studied compounds, it was noted that the absolute majority of substances retained their properties, which indicates their stability. When evaluating the effect of irradiation of microbial inoculum with low-intensity laser radiation on the susceptibility to chemical compounds, an increase in the sensitivity of irradiated microorganisms to some investigated chemicals was noted compared to similar non-irradiated microbial suspensions. In the case of 2 out of 9 studied chemical compounds we noted a 2- to 4-fold decrease in the minimal inhibitory concentration for irradiated microbial suspensions. A decrease in the minimal bactericidal concentration after irradiation was noted for one of the substances. In the cases of butynylthiobenzothiazolium hexabromotellurate, and tribromotelluromethylthiazoloquinazolinium bromide, decrease of both minimal inhibitory and minimal bactericidal concentrations in the irradiated inoculum was observed. The above shows that low-intensity laser radiation under certain parameters increases the susceptibility of microorganisms to antimicrobial agents.

The Credibility of Microbiological Diagnostics in MedicalDiagnostic Laboratories Based on the Results of POLMICROExternal Laboratory Quality Control POLMICRO 2023

<br>Introduction: The article describes results of the 30th edition of the Polish National ExternalQuality Assessment Scheme in Microbiology POLMICRO organised by the Centre of QualityControl in Microbiology (CQCM).</br><br>Aim: The evaluation of the reliability of the microbiological diagnostics performed bymedical diagnostic laboratories in Poland.</br><br>Materials and methods: The organiser analysed the results achieved by participants ofprogrammes conducted by CQCM in 2023 concerning important stages of microbiologicaldiagnostics such the as microscopic analysis of Gram-stained slides, identificationof etiological factors of infections, assessment of antimicrobial susceptibility ofmicroorganisms and the detection of antimicrobial resistance mechanisms.</br><br>Results: A positive annual assessment in the POLMICRO 2023 programme was achieved by98.33%, so 413 of 420 participants of the POLMICRO 2023 programme, and all laboratories participatingin the POLMICRO/SSE (n = 132) and POLMICRO/MIKOLOGIA (n = 139) programmes.</br><br>Conclusions: The results of external quality control programmes confirm the reliability oftesting and the high level of microbiological diagnostics performed by medical diagnosticlaboratories in Poland.</br>

Characteristics of the frequency and sensitivity to antimicrobial drugs of Staphylococcus aureus and Pseudomonas aeruginosa isolates of the lower respiratory tract of pediatric patients with cystic fibrosis in the Moscow region

Chronic lung infection is the leading cause of death in patients with cystic fibrosis. The article highlights the data of a microbiological examination of children and adolescents with cystic fibrosis living in the Moscow region and the results of determining the antibiotic susceptibility of the main isolated pathogens. The purpose of the study was to study the spectrum of the microflora of the respiratory tract of children and adolescents with cystic fibrosis with the determination of the antibiotic sensitivity of the isolated strains of S. aureus and P. aeruginosa. Material and methods. A study was made of the discharge of the upper and lower respiratory tract in 127 (66.6%) pediatric patients with cystic fibrosis under the age of 18 years using the bacteriological method of research. Results and discussion. In children and adolescents with cystic fibrosis, S. аureus was isolated from the biological material of the upper and lower respiratory tract in 70.1% of cases, in 46.5% in monoculture and in 24% in association with other microorganisms. P. aeruginosa isolated in 23.6%, in monoculture 8.0%. In most cases, P. aeruginosa was associated with S. аureus. MRSA has been identified in 6.4% of children and adolescents with cystic fibrosis. The studied strains of S. aureus were 33% sensitive to benzylpenicillin, 25% to chloramphenicol and were resistant (75%) to ciprofloxacin. 56% of S. aureus strains remained sensitive to erythromycin. P. aeruginosa strains were resistant to ticarcillin/clavulanate), fluoroquinolones, third-generation cephalosporins, imipenem, and aztreonam. Conclusion. P. aeruginosa retains sensitivity to meropenem and aminoglycosides, and S. aureus to tigecycline, teicoplanin, vancomycin, linezolid, fosfomycin, and fusidic acid. Monitoring the antibiotic susceptibility of microorganisms isolated from patients with cystic fibrosis allows you to optimize the tactics of antimicrobial therapy, taking into account the revision of the criteria of the European Committee for the determination of sensitivity to antimicrobial drugs (EUCAST).

Characterization and decontamination of deposited dust: a management regime at a museum

Deposited dust represents a nutritional niche for microflora. Inhibiting microflora-associated deposited dust is a critical approach to manage cultural heritage buildings. Knowledge on the effectiveness of commercial disinfection on microflora in a real field environment is limited. The present study aims to: (1) characterize deposited dust composition, and (2) assess the effectiveness of several commercial biocides/and an air ionizer on microflora-associated floor surface and air before and after treatment. Deposited dust was collected using a dust collector and microbial air sampling was conducted via a volumetric impactor sampler. Susceptibility of microorganisms to biocide/ionizer was performed in a naturally ventilated unoccupied room with a floor area of 18 m2. One-treatment protocol, a daily disinfection mode, was applied to each biocide/ionizer. The surface floor was adjacently sprayed by a biocide, and the ionizer was turned on for 30 min. Indoor deposited dust rates varied between 0.75 and 8.7 mg/m2/day with indoor/outdoor ratio of ~ 1:100. Ion concentrations of NH4+, Cl−, SO42− and NO3− were higher indoor than outdoor. The concentration of microorganisms-associated deposited dust averaged 106 CFU/g; 105 CFU/g and 104 CFU/g for bacteria, fungi and actinomycetes, respectively. A total of 23 fungal taxa were identified, with Aspergillus flavus, Asp. fumigatus and Asp. niger were the predominant taxa. Biocides quickly reduced floor surface and airborne microbial loads. The biocidal effect was time limited, as microflora loads increased again after ~ 4 days of the treatment protocol. Benzalkonium chloride (BAC) out-performed other biocides, showed a relatively permanent microbial inhibiting effect. The air ionizer reduced airborne microorganisms and increased surface floor ones. Characterizing of deposited dust (rate and composition) and choice an appropriate biocide may effectively reduce biodeterioration. Further real field treatment trials under various microenvironmental conditions are needed to determine the effectiveness of disinfection treatment.

Use of Antibiotics following Snakebite in the Era of Antimicrobial Stewardship.

Even though there are guidelines for the management of snakebite envenoming (SBE), the use of antibiotics in this pathology remains controversial. The aim of this study is to provide a narrative review of the literature and recommendations based on the best available evidence regarding antibiotic use in SBE. We performed a narrative review of relevant literature regarding SBE and antibiotic use as prophylaxis or treatment. A total of 26 articles were included. There is wide use of antibiotics in SBE; nevertheless, infection was not necessarily documented. The antibiotics used varied according to the study, from beta lactams to lincosamide and nitroimidazoles, and from monotherapy to combined antimicrobials. The most common recommendations were to manage skin and soft tissue infections and avoid infectious complications, but these suggestions are not necessarily based on bacteriological findings. Prophylactic use of antibiotics in SBE is discouraged in most studies. Antibiotic prescription in SBE should be based on the susceptibility of microorganisms isolated from the affected tissue or identified in snakes' oral cavities. Antibiotics should be reserved only for patients with a demonstrated infection, or those at a high risk of developing an infection, i.e., presenting severe local envenoming, local signs of infection, or those with incorrect manipulation of wounds. Prospective studies are needed to correlate microbiological findings at the wound site and the response to antibiotic use.

Antimicrobial Activity of Nanozirconium Oxide.

The goal behind this work is to prepare, characterize, and study the antimicrobial behavior of zirconia (ZrO2) nanoparticles (NPs). Various techniques, such as X-ray diffraction (XRD), were used for studying the mineralogical structure and crystal size. The microstructure and chemical composition of the prepared particles were analyzed using a scanning electron microscope attached with an energy-dispersive X-ray analysis (EDAX) unit. The antagonistic ability against several Gram-negative and Gram-positive bacteria, including Salmonella paratyphi, Pseudomonas aeruginosa, Alcaligenes aquatilis, Escherichia coli, Streptococcus pneumoniae, and Staphylococcus aureus, was assessed using the well diffusion method. The results of XRD and scanning electron microscopy (SEM) analyses revealed that the prepared material exhibited the phase of zirconium nanoparticles with particle sizes ranging between 40 and 75 nm. The antimicrobial test results demonstrated that the inhibitory effect increased with the increase of concentration. The inhibitory effect was more pronounced against Gram-positive bacteria, as indicated by the larger size of the inhibitory zone. At a 9% dimethyl sulfoxide (DMSO) concentration, the inhibitory zone had a diameter of 3.50 mm for S. aureus compared to a diameter of 3.40 mm for S. pneumoniae. The use of zirconium oxide nanoparticles reduced the diameter of the inhibitory zone when tested against S. aureus at a 3% DMSO concentration (0.50 mm diameter) and against S. pneumoniae (0.40 mm diameter). Zirconia nanoparticles were also evaluated for their antifungal activity against several species, including Aspergillus niger, Aspergillus flavus, and Penicillium sp. The size of the inhibitory zone indicated the susceptibility of microorganisms to nanozirconium oxide, resulting in a stronger inhibition of Penicillium sp. at a 100% DMSO concentration (4.50 mm diameter) compared to A. niger and A. flavus (3.00 mm diameter). The results for Penicillium sp. at a 3% DMSO concentration showed a diameter of the inhibitory zone of 0.90 mm, while for A. niger and A. flavus, the diameter was 0.80 mm. Thus, our findings demonstrate that the zirconium oxide nanoparticles possess the capability to reduce the inhibition zone effectively for both bacterial and fungal activities.

Antimicrobial efficacy of Tejpata

Treatment with antibiotics became so common that people start using these drugs even for the little of ailment resulting in misuse of antibiotics. This leads to decrease in susceptibility of microorganisms to the present antibiotics or antimicrobial agents. Currently, in addition to antibiotics and chemically synthesized drugs, the trend to look out for alternative medicines such as natural or herbal medicines is increasing because of fewer side effects or toxicity owing to their natural sources. Therefore, the need for novel / more effective antimicrobial drugs, is an absolute necessity and remains a very important area of research against pathogens. In the present study, antifungal and antibacterial effect of leaves has been evaluated against three fungal and five bacterial strains via methanolic extract. showed moderate growth inhibition against the fungal strain The methanolic extract of the leaves of the plantalsoshowed average activity against the three bacterial strains viz., and .

Evaluation of distribution and susceptibility of microorganisms isolated from joint fluid cultures: five-year data

Aims: Septic arthritis is joint inflammation. It is an orthopedic emergency that requires prompt diagnosis and treatment. In this study, it was aimed to examine the distribution and antibiotic resistance profiles of microorganisms isolated from joint fluid samples taken from patients who applied to the orthopedic clinic of our hospital in the last five years. 
 Methods: In our study, 1162 joint fluid samples were sent to the medical microbiology laboratory of our hospital from the orthopedics and traumatology clinic between January 01, 2018 and December 31, 2022. Joint fluid samples taken from clinically appropriate patients under sterile conditions were incubated in a BacT/Alert 3D (Biomerieux, France) culture device. Bacteria isolated from 164 specimens with growth detected, were identified by matrix-mediated laser desorption/ionization-time-of-flight mass spectrometry (MALDI-TOF MS) based VITEK MS (Biomerieux, France). Antibiotic susceptibility tests were performed on the VITEK 2 Compact (Biomerieux, France) device.
 Results: Staphylococcus aureus (S. aureus) (29.3%) and coagulase negative Staphylococci (CNS) (29.3%) were the most commonly grown microorganisms. Other microorganisms grown were Streptococcus spp. (9.1%), Enterococcus spp. (6.1%), Pseudomonas aeruginosa (P. aeuruginosa) (7.3%), Escherichiae coli (E. coli) (4.3%) and Klebsiella pneumoniae (K. pneumoniae) (4.3%). When antibiotic susceptibility results were evaluated according to EUCAST restricted reporting criteria, linezolid in Gram-positive strains, amikacin in Enterobacterales, colistin and tigecycline in nonfermentative Gram-negative bacteria were found to be the most susceptible antibiotics. 
 Conclusion: The continuous change in antibiotic susceptibility profiles in joint infections, the long duration of treatment and follow-up, and the increase in polymicrobial infections require regular monitoring of culture and antibiotic susceptibility tests. In our study, the distribution of microorganisms isolated from joint fluid samples of our hospital and the determination of antibiotic resistance profiles will contribute to the clinician in terms of guiding empirical treatment.

Evaluation of the Antibiotic Susceptibility Patterns of Isolates from Feed and Water of Selected Poultry Farms in Awka Anambra State, Nigeria

The susceptibility of microorganisms isolated from poultry feeds and poultry water samples to selected antibiotics was assessed. Standard methods were used to analyze selected poultry feeds and poultry water samples. The antibiotic susceptibility patterns of the bacterial isolates were determined against the following antibacterial agents: erythromycin (10 µg), ciprofloxacin (10 µg), ampiclox (20 µg), rifampicin (20 µg), amoxil (20 µg), septrin (30 µg), ampicillin (30 µg), ceporex (10 µg), levofloxacin (20 µg), gentamicin (10 µg), streptomycin (30 µg), norfloxacin (10 µg), chloramphenicol (30 µg), ofloxacin (10 µg), nalidixic acid (30 µg), reflecine (10 µg), and augmentin (30 µg).The highest viable counts of bacteria isolated from poultry feed and water samples were 2.7x106 cfu/g and 1.69x103 cfu/ml, respectively. The highest fungal counts in the poultry feed and water samples were 1.60x105 cfu/g and 2x105 cfu/ml, respectively. Bacterial isolates from poultry feed and water samples included Escherichia coli, Klebsiella pneumoniae, Salmonella species, and Staphylococcus aureus. Fungal isolates included Aspergillus species, Penicillium species, Mucor species, and Candida species.Staphylococcus aureus exhibited the highest susceptibility to most of the antibiotics, while Klebsiella pneumoniae showed the highest resistance, as it was resistant to five out of the ten antibiotics tested in this study. The research has demonstrated that poultry feed and poultry water showed varying levels of contamination, which may pose serious health risks to poultry. Amoxil, levofloxacin, ciprofloxacin, reflecine, and ofloxacin are recommended for use as antibiotics to treat diseases that may be caused by some of these pathogens.

IDENTIFICATION OF MICRORGANISMS BY USING AUTOMATED MICROBIAL DETECTION SYSTEM IN ADULT PATIENTSSUSPECTED WITH SEPTICAEMIA WITH ITS SUPPLEMENTARY PARAMETERS

Septicaemia is a major cause of mortality in both developed and developing countries. Despite important progress in treatment and prevention of infectious diseases, they are considered as leading cause of death and disability. The purpose of this study was monitoring the spectrum of microorganisms that invade blood stream and to study role of different markers in septicaemia, such data are often used to determine empiric antibiotic therapy, to alert clinicians to emerging pathogens that may pose a threat to community and also help in diagnosing severity of septicaemia. Aims and Objectives: To isolate and study the microorganisms from septicaemiccases, to study antimicrobial susceptibility of microorganisms isolated from septicemic casesandto study role of different markers in septicemic cases. Which help in diagnosing severity of septicaemia. Methodology: The study was conducted from September 2015 to February 2017 in a tertiary care teaching hospital. 1993 samples were collected from patients clinically suspected patients of septicaemia. They were inoculated and then incubated, and gram staining was performed. Antibiotic resistance and susceptibility were measured by the disk diffusion method according to the Clinical and Laboratory standards institute (CSLI) guidelines Result:Out of 1993 patients having, 695(34.87%) were culture positive. Among Gram negative isolates, Klebsiella spp.(14.96%)was commonest followed by Acinetobacter species (13.66%) ,E.coli (7.76%),Pseudomonas aeruginosa (6.76%) and salmonella spp.(1.29%). Among Gram positive organisms in our study CONS was the commonest (14.53%) followed by S. aureus (10.79%) and Enterococcus (6.18%), Streptococcus species (1.72%). It shows that colistin was found to be more sensitive for gram negative organisms followed by aminoglycosides and carbapenem group, while resistance was observed towards fluoroquinolone, 1st and 2nd generation cephalosporine groups. &Vancomycin, Teicoplanin and Linezolide were highly active drugs against Gram positive organisms. Conclusion:Septicaemia is an important cause of morbidity and mortality. The study conducted showed both Gram positive and Gram-negative bacteria were responsible for septicaemia. Most of the strains were multi drug resistant and leaving limited options for treatment. Thus, timely detection and knowledge of most likely pathogens causing septicaemia along with their antibiotic susceptibility pattern will help the clinicians in choosing appropriate antimicrobials for treatment which will reduce the major burden of septicaemia in critically ill patients and will also minimize the further emergence of resistance. Therefore, there should be an intensive surveillance, antibiotic policy formulations and preventive efforts for the effective management and prevention of drug resistance.

P02 Antimicrobial susceptibility of microorganisms isolated in community-acquired pneumonia in drug-dependent patients

Abstract Objectives To investigate the nature and susceptibility of community-acquired pneumonia (CAP) pathogens in drug-dependent patients. Materials and methods The susceptibility of community-acquired pneumonia pathogens isolated from sputum was studied in 31 drug-dependent patients. 13 (42%) were women and 18 (58%) were men. The average age of this group was 28.6 ± 1.2 years. The antimicrobial activity of the main groups of antibiotics was studied in comparison with the susceptibility of the archive Staphylococcus aureus ATCC25923 strain. Results In total, 51 strains of microorganisms were isolated, among which S. aureus (19 strains, 37.3%) and fungi of the genus Candida (16 strains, 31.3%) prevailed, while in 15 cases, bacteria were inoculated in the form of monoculture, and in 16 cases in the form of associations of bacteria and fungi of the genus Candida. When studying the susceptibility of the isolated strains of microorganisms to the main groups of antibiotics, their high (P ≤ 0.05) resistance to the main groups of antimicrobial drugs used in standard treatment regimens for CAP was established. Conclusions CAP in drug-dependent patients has a severe complicated course due to the combination of highly virulent bacterial and fungal infections. The causative agents of community-acquired pneumonia in drug-dependent patients have low susceptibility to the main groups of antibiotics used in the treatment of this pathology.

Toxicity, Antibacterial, and Phytochemical Analyses of Antrocaryon klaineanum Pierre Extracts.

Medicinal plants are traditionally used in Gabon to treat several types of illnesses. The study's purpose was to determine the toxic, antibacterial, and anti-inflammatory effects of Antrocaryon klaineanum Pierre extracts and to characterize their phytochemical compounds. Toxicity was evaluated on frog tadpoles (Phrynobatrachus africanus Hallowell). The microorganism susceptibility test was performed by the diffusion method, while minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) were evaluated using the microdilution technique. Anti-inflammatory activity was tested through protein denaturation and membrane stabilization methods. Chromatography and molecular network techniques were used to characterize chemical compounds. The lethality test showed that the lethal concentration (LC50) increased from 110.03 ± 1.25 to 15.86 ± 2.21 μg/mL after 24 and 96 hours of exposure. In tadpoles exposed to 7.81 μg/mL extract, the first mortalities (12.5%) were observed on the fifth day of exposure. A relative decrease in mature erythrocytes exposed to plant extracts was observed. The antibacterial activity shows that the Ak F2, Ak F3, and Ak F4 fractions (from the water-ethanol crude extract) gave the greatest antibacterial activities compared to the other extracts. The water, water-acetone, and water-ethanol extracts showed good inhibition of denaturation. The haemolysis test shows that the extracts exhibited good anti-inflammatory activities. Phytochemical characterisation revealed four major compounds, including monogallate epicatechin and hydroxy-ergostadian. The molecular network revealed five main clusters. Our study shows that A. klaineanum Pierre could be a promising natural product for the isolation of molecules with potential biological activities.

POSSIBLE USE OF LASERS FOR CLEAVAGE OF PHENOLS TILL BASE SUBSTANCES (REVIEW)

The purpose of this review article is to explain the hazards of phenol and phenol compounds to human health and the environment. To describe where and how phenol and its compounds occur, especially in industrial effluents. To study the possibility of using laser technologies for phenol cleavage, as well as for the treatment of industrial wastewater from phenol compounds. Removal of phenol and its compounds using biological wastewater treatment process is widely used worldwide. This method is cost-effective and environmentally friendly. On the other hand, exceeding the tolerable phenol concentration, which is individual for each biological treatment plant, may result in severe intoxication and lead to death of activated sludge system. Thus, the biological treatment process of industrial wastewater is halted until the phenol concentration is reduced to an acceptable level and the microorganisms have time to recover. Such a procedure can be time consuming and unpredictable due to the susceptibility of microorganisms to changing conditions. Based on this, sources of literature have been studied that could help to understand which laser equipment can be used to cleave a phenolic compound or benzene ring to simpler compounds.

Identification and antibiotic susceptibility of microorganisms isolated from diabetic foot ulcers: A pathological aspect.

Diabetic foot ulcers infected with microorganisms increase the risk of amputation. The presence of drug-resistant bacteria in diabetic foot ulcers creates a big challenge during the treatment. The objective of the present study was to determine the bacterial prevalence and antibiotic resistance among bacteria isolated from Chinese patients with diabetic foot ulcers. The present study studied the microbial colonization of diabetic foot ulcers of patients from a single center in China. Wound swabs from 89 patients with diabetic foot ulcers were collected and the presence of microorganisms detected. The isolated microorganisms were subjected to antibiotic susceptibility testing by the disk diffusion method. Of 89 patients, 56 (62.9%) were male and 33 (37.1%) were female, the mean age of patients was 53.2±5.4 years, the mean duration of diabetes was 14.8±2.9 years, the mean random blood sugar was 301±87 mg/dl, mean HbA1c was 7.9±1.4%. Patients with Wanger ulcer grade III (36.0%; P=0.034) and patients within the weight range of 51-75 kg (59.6%; P=0.012) were significantly higher. The prevalence rate of diabetic foot ulcers was 11.3%. Among 153 microorganisms, gram-positive bacteria (52.3%) were more prevalent than gram-negative bacteria (44.4%). Most of the patients with polymicrobial infection were classified to have Wanger III ulcer grade diabetic foot ulcers. Staphylococcus aureus (38.2%) was the most predominant bacteria isolated followed by Staphylococcus epidermidis (29.2%) and Escherichia coli (28.1%). Most of the gram-positive and gram-negative bacteria were resistant to dicloxacillin (73.8%, P=0.021) and cefotaxime (50%), respectively and ~53.4% of the isolates were multi-drug resistance isolates, 61.8% of the Staphylococcus aureus were identified as methicillin-resistant Staphylococcus aureus and 61.8% of the gram-negative bacteria were extended-spectrum β-lactamase producers. Staphylococcus aureus and Escherichia coli were the predominant gram-positive and gram-negative bacteria isolated, respectively. Penicillin resistance was significantly higher among the gram-negative bacteria (P=0.019). Staphylococcus aureus and Escherichia coli were the predominant gram-positive and gram-negative bacteria isolated and levofloxacin and nitrofurantoin were the most effective antibiotics among the gram-positive and gram-negative bacterial isolates, respectively.

SENSITIVITY OF MICROORGANISMS ISOLATED FROM PATHOLOGICAL MATERIAL TO ANTIMICROBIAL PREPARATION

Excessive and uncontrolled use of antibiotics commonly results in the emergence of antimicrobial resistance (AMR). Therefore, the main aim of these studies was to determine the antibiotic susceptibility of microorganisms isolated from the pathological material.
 The article describes the susceptibility of isolated strains to the following antibiotics: ampicillin, amoxicillin, oxacillin, ofloxacin, streptomycin, cefazolin, gentamicin, amikacin, amoxiclav, erythromycin, enrofloxacin, lincomycin, tetracycline, doxycycline, vancomycin, rifampicin, ciprofloxacin, norfloxacin, tylosin, nitrofurantoin, polymyxin B.
 During the study of six Escherichia coli and three Salmonella enteritidis strains, it was ascertained that they demonstrated different susceptibility to the studied antibiotics, in particular, only two E. coli isolates, which is 33,3 %, were resistant to streptomycin, 50 % of the isolated strains were susceptible.
 When determining the susceptibility, it was established that all isolated E. coli isolates were resistant to cefazolin, vancomycin, oxacillin, and 83,3 % were resistant to amoxicillin, ampicillin, vancomycin, amoxiclav, rifampicin.
 33,3 % of Salmonella enteritidis isolates were moderately susceptible to streptomycin, amoxicillin, and ampicillin, and 66,7 % were sensitive to ciprofloxacin, norfloxacin, and enrofloxacin.
 All isolated S. enteritidis strains were found to be resistant to cefazolin, tylosin, vancomycin, oxacillin, lincomycin, and erythromycin, 100 % susceptible to ciprofloxacin, amikacin, and ofloxacin and 68,7 % moderately susceptible to amoxicillin and gentamicin.

Актуальные вопросы резистентности микроорганизмов к дезинфицирующим средствам

Resistance of microorganisms to antimicrobial agents (antibiotics, antiseptics and disinfectants) is a national problem, which requires careful attention and actions to solve it. Excessive and improper use of disinfectants can affect the reduction of susceptibility of microorganisms. This report presents the types of resistance of microorganisms, factors contributing to its formation and possible ways to overcome microbial resistance. Keywords: resistance of microorganisms, disinfectants, biocides, monitoring.

Preparation and characterization studies of chitosan encapsulated ZnO nanoparticles modified with folic acid and their antibacterial activity against selected bacterial species

This article deals with the preparation of Chitosan (CS) coated Zinc Oxide (ZnO) nanoparticles modified with Folic Acid (FA) via the simple solvothermal method. The physicochemical properties were evaluated through characterization studies such as X-ray diffraction spectroscopy (XRD), Fourier transform infrared spectroscopy (FTIR), Scanning electron microscopy (SEM), Energy-dispersive X-ray spectroscopy (EDAX), UV-Visible spectroscopy (UV-Vis), and Thermogravimetric and differential thermal analysis (TG/DTA). The crystalline size of the nanoparticles examined was 21.45 nm and 16.57 nm. The samples were subjected to antibacterial test (Gram-positive S. aureus, B. subtilis, and Gram-negative E. coli, P. aerugenosa) by the modified Kirby- Bauer well diffusion method and minimum inhibitory concentration (MIC) by using the broth dilution method in 96-well microtiter plate. This method was used to test the susceptibility of microorganisms. At high concentrations, CS-ZnO nanoparticles were found to have the highest zone of inhibition against S. aureus (20 mm) and B. subtilis (20 mm) and the lowest against E. coli (18 mm) and P. aeruginosa (10 mm). The MIC results were determined to be in the order CS-ZnO ˂ FA-CS-ZnO. The zeta potential of nanoparticles was estimated to be −19.1 ± 6.60 mV (CS-ZnO) and −29.3 ± 5.56 mV (FA-CS-ZnO), respectively.

Antimicrobial V-Shaped Copper(II) Pentaiodide: Insights to Bonding Pattern and Susceptibility.

Antimicrobial resistance (AMR) is a major concern for the survival of mankind. COVID-19 accelerated another silent pandemic of AMR through the uncontrolled use of antibiotics and biocides. New generations of antimicrobial agents are needed to combat resistant pathogens. Crown ethers can be used as models for drug action because they are similar to antibiotics. Iodine is a well-known microbicide but is characterized by instability and short-term effectivity. Iodine can be stabilized in the form of polyiodides that have a rich topology but are dependent on their immediate surroundings. In addition, copper has been successfully used since the beginning of history as a biocidal agent. We, therefore, combined iodine and copper with the highly selective crown ether 1,4,7,10-tetraoxacyclododecane (12-crown-4). The morphology and composition of the new pentaiodide [Cu(12-crown-4)2]I5 was investigated. Its antimicrobial activities against a selection of 10 pathogens were studied. It was found that C. albicans WDCM 00054 is highly susceptible to [Cu(12-crown-4)2]I5. Additionally, the compound has good to intermediate antimicrobial activity against Gram-positive and Gram-negative bacilli. The chain-like pentaiodide structure is V-shaped and consists of iodine molecules with very short covalent bonds connected to triiodides by halogen bonding. The single crystal structure is arranged across the lattice fringes in the form of ribbons or honeycombs. The susceptibility of microorganisms towards polyiodides depends on polyiodide bonding patterns with halogen-, covalent-, and non-covalent bonding.

Assessment of Microbiological Environment and the Level of Antibiotic Resistance in a Multidisciplinary Hospital

The objective: to determine the incidence and drug sensitivity of the main pathogens causing community-acquired and nosocomial infections in patients staying in a multidisciplinary hospital.Subjects and Methods: a retrospective study of the microbiological population in patients of a multidisciplinary hospital was carried out. The period over 3 years was assessed. 3,954 samples of biological materials from various sites were studied.Results: gram-positive bacteria prevailed in the general structure of microbial environment of patients – Staphylococcus aureus (28%), and Enterococcus faecalis (10%), as well as gram-negative – Escherichia coli (26%), and Klebsiella pneumoniae (13%). The majority of non-fermenting gram-negative microorganisms isolated from patients in the intensive care unit demonstrated multiple resistance and quantitatively prevailed over those in surgery units. The spectrum of antibiotic susceptibility of microorganisms of the same species isolated from patients of therapy and surgery departments differed.