Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC) for Twelve Antimicrobials (Biocides and Antibiotics) in Eight Strains of Listeria monocytogenes

When selecting effective doses of antimicrobials, be they biocides or antibiotics, it is essential to know the minimum inhibitory concentrations (MICs) and minimum bactericidal concentrations (MBCs) of these substances. The present research determined the MICs and MBCs for three biocides, sodium hypochlorite (SH), benzalkonium chloride (BC), and peracetic acid (PAA), and nine antibiotics in eight strains of Listeria monocytogenes of varying serotypes. Marked intra-species differences were observed in the resistance of L. monocytogenes to the biocides and antibiotics. The MICs (ppm) for the biocides ranged between 1750 and 4500 for SH, 0.25 and 20.00 for BC, and 1050 and 1700 for PAA. Their MBCs (ppm) ranged from 2250 to 4500 for SH, 0.50 to 20.00 for BC, and 1150 to 1800 for PAA. The MICs (ppm) for antibiotics lay between 1 and 15 for ampicillin, 8 and 150 for cephalothin, 20 and 170 for cefoxitin, 0.05 and 0.20 for erythromycin, 4 and 50 for chloramphenicol, 3 and 100 for gentamicin, 2 and 15 for tetracycline, 2 and 80 for vancomycin, and 160 and 430 for fosfomycin. The corresponding MBCs (ppm) were from 5 to 20 for ampicillin, 9 to 160 for cephalothin, 70 to 200 for cefoxitin, 4 to 5 for erythromycin, 9 to 70 for chloramphenicol, 5 to 100 for gentamicin, 3 to 30 for tetracycline, 3 to 90 for vancomycin, and 160 to 450 for fosfomycin. Notably, erythromycin showed considerable efficacy, demonstrated by the low values for both MIC and MBC. Based on EUCAST and the CLSI criteria, all strains were susceptible to erythromycin. All strains were resistant to cephalothin, cefoxitin, gentamicin, and fosfomycin. Further values for resistance were 87.50% for ampicillin and vancomycin, 75.00% for tetracycline, and 62.50% for chloramphenicol. The high prevalence of antibiotic resistance is a matter for concern. A positive correlation was found between MIC and MBC values for most of the biocides and antibiotics. The higher the hydrophobicity of the cell surface, the higher the susceptibility to biocides, suggesting that surface characteristics of bacterial cells influence resistance to these compounds.

Analysis of patient medical exposure in X-ray diagnostics in Russia for half a century (1970–2019)

During last 50 years, firstly in the RSFSR in the USSR (1970-80), then in the Russian Federation - RF (1990-2019), the authors studied the radiation safety issues of patients from medical exposure. The reader is offered a complex radiation-hygienic analysis of the 50-year medical exposure of patients and of the population in Russia to inform and analyze the available data on the most common type of use of ionizing radiation sources in the national economy. For a half century, several generations of people have changed and medical diagnostic X-ray equipment and technologies have also radically changed. The information from this article was obtained on the basis of radiation-hygienic statistics, as well as considered our research. The data is presented at the federal level in the form of the volume of research carried out- determined by the number of X-ray procedures, as well as the level of medical exposure in the form of effective dose of patients in Russia - a huge region with a population of about 150 million people, where about 200 million X-Ray procedures were performed annually, i.e. about 10 billion X-Ray procedures for the entire observation period. During the study, a collective effective dose was - 6.5 million person-Sv at the rate of 100 thousand person-Sv and more per year. The paper presents the dynamics and the structure of the studied indicators depending on the type of medical exposure, as well as its localization. The contribution of the X-ray diagnostics to the total volume of radiation diagnostics, which is developing dynamically, is presented. It was found that throughout the study, there were two oppositely directed processes: an increase in the number of X-Ray procedures and a decrease in the effective doses of patients. At present, the minimum dose has been reached, after that it has been increasing began, associated with the use of new computer technologies. It was determined that, depending on the localization, the main radiation load during X-ray procedures falls on the skeleton and digestive organs. It is shown that during the study period (in 1986) there was an accident at the Chernobyl, which significantly affected on medical activities and, in particular, X-ray diagnostic indicators. The paper shows the consequences of these situations. In general, the data presented is huge in volume and significant in information content. The information obtained on the basis of such a unique data is representative and allows, firstly, to analytically study the issues of radiation protection of patients and, secondly, to plan the strategy and tactics of its development.

Meloxicam efficacy and safety in treatment of pain syndromes of different localization according to domestic studies

More than 500 million people worldwide suffer from osteoarthritis (OA). Neck and low back pain (LBP) is one of the most common reasons for visiting a general practitioner to receive primary medical care in different countries. The prevalence of chronic LBP varies from 4% to 20%, and increases linearly from the third decade to 60 years, and stabilizes in the seventh decade of life. According to the latest published clinical guidelines of the Russian Association for the Study of Pain, nonsteroidal anti-inflammatory drugs (NSAIDs) are used in minimally effective doses and a short course to relieve acute musculoskeletal pain. The ratio of the NSAIDs activity associated with cyclooxygenase (COX) – COX-1 / COX-2 – inhibition allows us to evaluate their potential toxicity. The smaller this value, the more selective the drug is against COX-2, and the less toxic it is. Meloxicam belongs to the predominantly selective COX-2 inhibitors. In the Russian market, meloxicam of domestic production - Amelotex® is widely prescribed. Several studies have shown the high efficacy and safety of meloxicam in the treatment of pain syndromes with different localizations (LBP, neck pain of vertebrogenic nature, OA, etc.), it can be recommended for elderly patients, patients with comorbid diseases such as arterial hypertension (AH), diabetes mellitus, gastrointestinal tract pathology. Meloxicam has a good efficacy and safety profile, a pronounced symptom-modifying effect.

Toxicological Activity of the Methanolic Leaf Extract of Some Medicinal Plants Used in Sokoto Township and Environs

Inspite of the availability of different antiseptic and antibiotics in most localities in some parts of the world, there is still a number of information on the usage of some local plants in various kinds of treatments of different ill-health conditions. Leaves of Ocimum basilicum, Leptadania hastata and Momordica balsamina are locally used by traditional birth attendants at pre and post-partum periods. The present study investigates the phytochemical compositions and toxicity of the leaf extracts of the plants against isolates of Listeria monocytogenes. Standard microbiological techniques and polymerase chain reaction was used to isolate and identify the bacteria. Phytochemical analysis was done and cytotoxicity of the extracts at different concentrations (MBC, OBC and LHC) were determined using human erythrocytes. Results of the phytochemical analysis revealed the presence of tannins, flavonoids, carbohydrates, alkaloids, terpinoids and glycosides in the studied extracts. Toxicity to erythrocytes, expressed as percentage hemolysis of only 17.27% (MBC1) was seen in one of the plants; M. balsamina. Similarly, the other extracts exhibited minimal toxicity to human erythrocytes (LHC1= 15.45%; OBC1= 7.6%). It was concluded that all the plant leaf extracts are safe for human consumption. Studies on the preparation, effective doses and side effects of these extracts in vivo are hereby recommended.

Assessment of Activity Concentration of Radionuclides in Soil and Cassava Food Crop from Solid Mineral Mining Site in Ishiagu, Ivo L.G.A of Ebonyi State, Nigeria

The assessment of activity of concentration of radionuclides in soil and food crops from solid mineral mining sites at Ishiagu, in Ivo L.G.A of Ebonyi State was carried out using the necessary measuring instruments. Samples of soil and cassava crop collected from around the mining sites. The samples were analysed using gamma ray spectrometry. The average activity concentration of 226Ra, 232Th and 40K in soil samples were 12.37,16.08, and 144.29 Bqkg-1 while those for cassava were 2.81, 16.80, and 205.41 Bqkg-1. The soil/plant radionuclide transfer ratio estimated are 0.62, 2.43 and 2.51 for 226Ra, 232Th and 40K, respectively. All the radiological risk parameters estimated are relatively low. The result of this work showed that the obtained results for all samples were lower than the international accepted limit. Hence, from radiological health standpoint, the obtained values of effective doses may not pose significant threat to both human and the environment.

A Review of Doses for Dental Imaging in 2010–2020 and Development of a Web Dose Calculator

Dental imaging is one of the most common types of diagnostic radiological procedures in modern medicine. We introduce a comprehensive table of organ doses received by patients in dental imaging procedures extracted from literature and a new web application to visualize the summarized dose information. We analyzed articles, published after 2010, from PubMed on organ and effective doses delivered by dental imaging procedures, including intraoral radiography, panoramic radiography, and cone-beam computed tomography (CBCT), and summarized doses by dosimetry method, machine model, patient age, and technical parameters. Mean effective doses delivered by intraoral, 1.32 (0.60–2.56) μSv, and panoramic, 17.93 (3.47–75.00) μSv, procedures were found to be about1% and 15% of that delivered by CBCT, 121.09 (17.10–392.20) μSv, respectively. In CBCT imaging, child phantoms received about 29% more effective dose than the adult phantoms received. The effective dose of a large field of view (FOV) (>150 cm2) was about 1.6 times greater than that of a small FOV (<50 cm2). The maximum CBCT effective dose with a large FOV for children, 392.2 μSv, was about 13% of theeffective dose that a person receives on average every year from natural radiation, 3110 μSv. Monte Carlo simulations of representative cases of the three dental imaging procedures were then conducted to estimate and visualize the dose distribution within the head. The user-friendly interactive web application (available at http://dentaldose.org) receives user input, such as the number of intraoral radiographs taken, and displays total organ and effective doses, dose distribution maps, and a comparison with other medical and natural sources of radiation. The web dose calculator provides a practical resource for patients interested in understanding the radiation doses delivered by dental imaging procedures.

Combined Toxicity of Xenobiotics Bisphenol A and Heavy Metals on Zebrafish Embryos (Danio rerio)

Environmental pollutants may cause adverse effects on the immune system of aquatic organisms. This study revealed that combination of environmental pollutants and Bisphenol A(BPA) could cause an acute inflammatory response in zebrafish larvae as shown by body alterations, which may imply a common immunotoxicity mechanism for most environmental pollutants. In the present study we evaluated the toxicity after co-exposure of BPA and Cd or Cr (III) in zebrafish embryos and larvae, and the oxidative stress pathway involved. Evaluation of lethal and developmental endpoints such as hatching, edema, malformations, abnormal heart rate and survival rate were evaluated after 96 h of exposure. Combination of BPA at 10 μM with Cd or Cr at 0.5 μM exposure induce malformations at 96 hpf in zebrafish larvae, as well as significantly increases oxidative stress and induce apoptosis on larvae. Our study suggested how environmental pollutant showed a synergistic effect at common not-effective doses, promoting decrease of antioxidant defense and contrasted fish development.

Effective Doses of Nalbuphine Combined With Propofol for Painless Gastroscopy in Adults: A Randomized Controlled Trial

Objective: This prospective study evaluated the 50% effective dose (ED50) and 95% effective dose (ED95) of nalbuphine combined with propofol during painless gastroscopy.Methods: Seventy-five patients who underwent painless gastroscopy were randomly divided into five groups (group N0, N0.05, N0.1, N0.15, and N0.2), with doses of 0, 0.05, 0.1, 0.15, or 0.2 mg/kg nalbuphine in each group. Propofol was given to all groups as the sedative. The bispectral index (BIS) value, propofol dose, examination time, and awakening time were recorded. The number of patients with intolerance indexes (coughing, retching, swallowing, or limb movement) was recorded in each group. The ED50/ED95 of nalbuphine combined with propofol for gastroscopy were calculated.Results: Compared with those of groups N0, N0.05, or N0.1, the propofol dose and awakening time were significantly reduced in group N0.15 or N0.2 (p &lt; 0.05). The successful rate of painless gastroscopy in group N0.15 or N0.2 significantly increased compared to that of group N0 or N0.05 (p &lt; 0.05). When combined with propofol, nalbuphine had an ED50 and ED95 for painless gastroscopy of 0.078 mg/kg (95% CI, 0.056–0.098 mg/kg) and 0.162 mg/kg (95% CI, 0.134–0.217 mg/kg), respectively.Conclusion: The ED50/ED95 of nalbuphine combined with propofol are 0.078 and 0.162 mg/kg, respectively, for painless gastroscopy. Nalbuphine at 0.162 mg/kg combined with propofol is effective and safe for painless gastroscopy in adults.