Antimicrobial Profiles Research Articles

P16 Overuse of antibiotics during the first year of the COVID-19 pandemic in Poland

Abstract Background It was a retrospective study conducted at the University Hospital in Kraków in Poland (UHC). The objectives of the study identify the trends of the antimicrobial consumption profile from February 2020 to February 2021, the first year of the COVID-19 pandemic in Poland. The hospital records data have been analysed to identify factors that were associated with antimicrobial consumption and illustrate how the situation evolved over time. The secondary objective is to identify the determinants of antimicrobial use. Methods The analysis was carried out on data based on electronically registered health care data from the UHC and hospital pharmacy. We included 250 adult patients, divided into 5 groups, and hospitalized with confirmed SARS-CoV-2 infection. The study began on 13 February 2020, when the patient with a confirmed hospital-acquired (HA)-COVID-19 in March was admitted to UHC. Next, we enrolled 49 consecutive patients and then, consecutive 50 patients admitted to the UHK on 13 May 2020, 13 August 2020, 13 November 2020 and 13 February 2021. Patients with HA-COVID-19 were eligible for inclusion in this study. Results In total, 178 patients received antimicrobials (ABX), 71.2% of all and the incidence rate of laboratory confirmed healthcare-associated infection (LC-HAI) was 20%. No patients had laboratory-confirmed bacterial co-infection at admission. The severity of COVID-19 was mild in 102 (40.8%), moderate in 92 (36.8%), and severe in 56 (22.4%) patients. Forty-three (17.2%) patients were hospitalized in an ICU, and 97.7% of them were treated with antimicrobials. The length of stay was greater among patients receiving ABX. The percentage of patients receiving antibiotic therapy changed throughout the covered time periods. The lowest proportion was recorded in May 2020 (48.0%), whereas the highest was observed in November 2021 and February 2021 (84.0% both). Systemic glucocorticoids (GCS) were used in 117 patients, 46.8% of all, significantly more frequently in patients with ABXs P<0.001. Patients with severe COVID-19 had the highest antimicrobial consumption values, the median DDD in this group was 20.92, P<0.001. Patients admitted at the beginning of the pandemic (February, May 2020) had significantly higher median DDD values, respectively 25.3 and 16.0 compared with those admitted in later months of the pandemic (August, November 2020; February 2021), 11.0, 11.0 and 11.2. Conclusions The results show that despite COVID-19 being a viral disease, the use of antimicrobials has been common in infected patients, especially at the beginning of the pandemic. The observed incidence of LC-HAI did not change during 12 months of follow-up and was very high, despite the fact that only 1/5 of the patients were hospitalized in the ICU.

Preparation of Laser-Ablated Ag Nanoparticle-MMT Clay-Based Beeswax Antibiofilm Coating.

Unlike other antimicrobial agents, Ag-based composites are stable and currently widely used as broad spectral additives, fighting microbial biofilms and other biological threats. The goal of the present study is to develop a green, multifunctional, and robust antibiofilm water-insoluble coating, inhibiting histamine-producing Lentilactobacillus parabuchneri biofilms. Herein, laser-ablated Ag NPs (L-Ag NPs) were incorporated into and onto a montmorillonite (MMT) surface layer with a simple wet chemical method, provided that the electrostatic interaction between L-Ag NPs and MMT clay led to the formation of L-Ag/MMT nanoantimicrobials (NAMs). The use of MMT support can facilitate handling Ag NPs in industrial applications. The Ag/MMT composite was characterized with transmission electron microscopy (TEM) and scanning electron microscopy (SEM), which confirmed the entrapment of L-Ag NPs into MMT clay. The surface chemical composition was assessed with X-ray photoelectron spectroscopy, proving that Ag NPs were in contact with and deposited onto the surface of MMT. The characteristic L-Ag/MMT band was investigated with UV-vis spectroscopy. Following that, the L-Ag/MMT composite was embedded into a biosafe water-insoluble beeswax agent with a spin coating technique. The antimicrobial ion release kinetic profile of the L-Ag/MMT/beeswax coating through an electrothermal atomic absorption spectroscopy (ETAAS) study supported the controlled release of Ag ions, reaching a plateau at 420 ± 80 nM, which is safe from the point of view of Ag toxicity. Microbial biofilm growth inhibition was assessed with real-time in situ Fourier transform infrared attenuated total reflection spectroscopy (FTIR-ATR) in a flow cell assembly over 32 h. The study was further supported by optical density (OD) measurements and SEM on bacteria incubated in the presence of the L-Ag/MMT/beeswax coating.

Antimicrobial susceptibility patterns of Escherichia coli isolated from cancer patients in National Cancer Hospital

Introduction: Escherichia coli (E. coli) is one of the leading causes of infections in cancer patients. Antibiotic-resistant E. coli is a major cause of treatment failure in infected cancer patients. This study aims to determine the prevalence and antibiotic susceptibility of E. coli in cancer patients from January 2022 to December 2022 at National Cancer Hospital. Materials and methods: We performed a retrospective review of the culture results of various clinical samples. Results: A total of 283 samples were analyzed to identify E. coli and its antimicrobial profiles. The prevalence of E. coli was 15.9%. The highest isolation rate was obtained from blood samples (35.56%). The highest rate of E. coli resistance was found in ampicillin (95.56%), followed by sulfamethoxazole/trimethoprim (77.76%) and ceftazidime (64.44%). The highest rate of E. coli sensitivity was found in fosfomycin (97.78%), followed by ertapenem, imipenem, meropenem, and amikacin (95.56% each), and nitrofurantoin (93.33%). About 55.56% and 80.0% were ESBL-positive and multidrug-resistant, respectively. Conclusion: E. coli isolates showed high rates of resistance to ampicillin, sulfamethoxazole/trimethoprim, and ceftazidime. Fosfomycin, ertapenem, imipenem, meropenem, amikacin, and nitrofurantoin are considered appropriate for the empirical treatment of E. coli. Regular monitoring of E. coli resistant to antibiotics is recommended.

Synthesis and Antimicrobial Activity of the Pathogenic E. coli Strains of p-Quinols: Additive Effects of Copper-Catalyzed Addition of Aryl Boronic Acid to Benzoquinones.

A mild and efficient protocol for the synthesis of p-quinols under aqueous conditions was developed. The pivotal role of additives in the copper-catalyzed addition of aryl boronic and heteroaryl boronic acids to benzoquinones was observed. It was found that polyvinylpyrrolidone (PVP) was the most efficient additive used for the studied reaction. The noteworthy advantages of this procedure include its broad substrate scope, high yields up to 91%, atom economy, and usage of readily available starting materials. Another benefit of this method is the reusability of the catalytic system up to four times. Further, the obtained p-quinols were characterized on the basis of their antimicrobial activities against E. coli. Antimicrobial activity was further compared with the corresponding 4-benzoquinones and 4-hydroquinones. Among tested compounds, seven derivatives showed an antimicrobial activity profile similar to that observed for commonly used antibiotics such as ciprofloxacin, bleomycin, and cloxacillin. In addition, the obtained p-quinols constitute a suitable platform for further modifications, allowing for a convenient change in their biological activity profile.

Prevalence and Antibiogram Pattern of Klebsiella pneumoniae in a Tertiary Care Hospital in Makkah, Saudi Arabia: An 11-Year Experience.

Infectious disease is one of the greatest causes of morbidity and mortality worldwide, and with the emergence of antimicrobial resistance, the situation is worsening. In order to prevent this crisis, antimicrobial resistance needs to be monitored carefully to control the spread of multidrug-resistant bacteria. Therefore, in this study, we aimed to determine the prevalence of infection caused by Klebsiella pneumoniae and investigate the antimicrobial profile pattern of K. pneumoniae in the last eleven years. This retrospective study was conducted in a tertiary hospital in Makkah, Saudi Arabia. Data were collected from January 2011 to December 2021. From 2011 to 2021, a total of 61,027 bacterial isolates were collected from clinical samples, among which 14.7% (n = 9014) were K. pneumoniae. The antibiotic susceptibility pattern of K. pneumoniae revealed a significant increase in the resistance rate in most tested antibiotics during the study period. A marked jump in the resistance rate was seen in amoxicillin/clavulanate and piperacillin/tazobactam, from 33.6% and 13.6% in 2011 to 71.4% and 84.9% in 2021, respectively. Ceftazidime, cefotaxime, and cefepime resistance rates increased from 29.9%, 26.2%, and 53.9%, respectively, in 2011 to become 84.9%, 85.1%, and 85.8% in 2021. Moreover, a significant increase in the resistance rate was seen in both imipenem and amikacin, with an average resistance rate rise from 6.6% for imipenem and 11.9% for amikacin in 2011 to 59.9% and 62.2% in 2021, respectively. The present study showed that the prevalence and drug resistance of K. pneumoniae increased over the study period. Thus, preventing hospital-acquired infection and the reasonable use of antibiotics must be implemented to control and reduce antimicrobial resistance.

Antimicrobial profile of coagulase-negative staphylococcus isolates from categories of individuals at a neonatal intensive care unit of a tertiary hospital, Ghana.

we compared the antimicrobial resistance profile of young infants' clinical isolates (from blood samples) of Staphylococcus epidermidis and haemolyticus with those colonizing mothers, clinical staff, and students. Also, screened for resistance to the watch and reserve classified groups, antibiotics not prescribed in the Ho Teaching Hospital (HTH), Ghana. a cross-sectional study was conducted from March to June 2018 to determine the antimicrobial susceptibility of twenty-one antimicrobials for 123 isolates consisting of 54 S. epidermidis and 69 S. haemolyticus cultured from the participants. VITEK 2 was used for antimicrobial susceptibility testing. Staphylococcal species were identified using matrix-assisted laser desorption/ionization-time of flight (MALDI-TOF). Statistical analysis was done with Grad-Pad prism. for S. epidermidis, clinical staff isolates have the highest methicillin-resistant (65%), followed by young infants' (50%) and mothers' and students' twenty-five percent each. Both young infants and clinical staff's Staphylococcus haemolyticus isolates have 100% methicillin-resistant, while mothers' and students' ones have 82% and 63%, respectively. We have identified resistance to one watch (teicoplanin), two reserves (tigecycline and fosfomycin) antimicrobial groups, and mupirocin, an unclassified group. identifying coagulase-negative staphylococci (CoNS) resistance to watch and reserve groups of antimicrobials in a non-previously exposed hospital calls for further studies to determine molecular mechanisms of resistance to these antimicrobials.

Antimicrobial Profiles and Conventional PCR Assay of Shiga Toxigenic Escherichia coli O157:H7 (STEC) Isolated from Cattle Slaughtered at Bedele Municipal Abattoir, South West Ethiopia.

Shiga toxin producing Escherichia coli O157:H7 (STEC) is considered the most prevalent food borne pathogen that has gained increasing attention worldwide in recent years. A cross-sectional study was carried out at Bedele Municipal abattoir on cattle that were reported healthy from detailed ante-mortem inspections and having various body conditions scores. A total of 516 samples were collected and examined after enriched in modified peptone water. Following an enrichment, the samples were plated onto MacConkey agar and then onto Eosin methylene blue agar. Finally after a few similar procedures, 14 E. coli O157:H7 (STEC) isolates were confirmed through latex agglutination test. The collected data were analyzed using SPSS version 20 statistical software. This study finding revealed that the overall prevalence of E. coli O157:H7 out of 516 samples was found to be 2.7%. However, on sample type basis, the prevalence of E. coli O157:H7 from feacal samples, carcass swabs, butcher hand swabs and knife swabs were 4.7%, 3.3%, 1.1% and 1.1%, respectively. It was also found that that the prevalence of E. coli O157:H7 was significantly affected by age groups of slaughtered cattle (p<0.05). Moreover, in vitro antimicrobial susceptibility test result on average showed that almost all of E. coli O157:H7 isolates were highly susceptible to kanamycin and no resistance was shown to ciprofloxacin and gentamicin. Finally, the conventional PCR detection of stx1, st2 and hylA genes revealed that only 21.4% and 14.3% were found to contain stx1 and hylA genes respectively. To wrap up, this study showed that Shiga toxin producing E. coli O157:H7 (STEC) isolates were found with almost low overall prevalence rate from all sample sources in this study site. Therefore, improving abattoir facilities and slaughter house workers' personal hygiene are recommended to curtail E. coli O157:H7 meat contamination in this abattoir.

Production of ginger- and aloe vera-based herbal wines and their antimicrobial profiling

Production of ginger- and aloe vera-based herbal wines and their antimicrobial profiling

Bacterial Pathogens Isolated from Surgical Wound and Their Antimicrobial Resistance Pattern in A Government Hospital in Anambra, Nigeria

Surgical wound infections are among the most common healthcare-associated infections as complications associated with them can have a significant long-term effect on the morbidity, mortality, and quality of life for patients. Knowledge on local pathogens and sensitivity to antimicrobial agents are crucial for successful treatment and management of surgical wound infection. This study evaluates the bacterial pathogens present in infected surgical wounds and their antimicrobial susceptibility profile. A total of 200 wound swabs from 112 males and 88 female patients of ages from 10 – 70 years with surgical wound infection were collected using clean, sterile swabs and analyzed using standard microbiological methods. Antibiotic disk diffusion method was used to determine the antibiotic resistance profile. Result showed that 142(71%) wound specimens were culture positive while 58(29%) showed no growth on culture media. Majority of the culture positive wounds (90.1%) showed single bacterial growth while the remaining (9.9%) revealed poly-microbial growth. The isolates were found to belong to both Gram-positive 53(37.3%) and Gram-negative 89(62.7%) bacteria. The most predominant isolate from the infected surgical wound was Gram-positive Staphylococcus aureus 53 (37.3%), followed by Gram-negative Pseudomonas aeruginosa 45(31.7%), Escherichia coli 32 (22.5%) and Klebsiella pneumoniae 12 (8.5%). The result of their antibiotic sensitivity test showed that majority of the wound isolates were highly resistant to ampicillin 126(88.7 %), followed by erythromycin 114(80.3%), gentamicin 109(76.7%) and trimetoprim-sulphametoxazole 103(72.5%). The overall findings on antimicrobial profile revealed high level of antimicrobial resistance from microorganisms isolated from surgical wound infections to commonly prescribed antibiotics. Therefore, there is a need for adequate intervention to control the spread of antimicrobial resistance.

Prevalence of multidrug-resistant and extensively drug-resistant phenotypes of Gram-negative bacilli isolated in clinical specimens at Centre Hospitalo-Universitaire Ibn Rochd, Morocco.

antimicrobial resistance in gram-negative bacilli is one of the major concerns in public health. We aimed to evaluate gram-negative bacilli epidemiology, antimicrobial profiles, and the resistance´s mechanism for Enterobacteriaceae isolated from specimens of hospitalized patients in wards of University Hospital Center Ibn Rochd of Casablanca, Morocco. a prospective study of the patient's specimens, collected from December 2016 to 31st March 2017. Isolation and identification were performed using conventional biochemical tests. According to the European Committee on Antimicrobial Susceptibility Testing guidelines, antibiotic susceptibility was determined. Polymerase Chain Reaction (PCR) was used to detect β-lactamase and carabapenemase genes: CTX-M, SHV, TEM, OXA-48, NDM, and VIM among the Enterobacteriaceae. according to inclusion criteria, 38 Enterobacteriaceae, 25 Acinetobacter baumannii (A. baumannii), and 10 Pseudomonas aeruginosa (P. aeruginosa) were included during the study period; these bacteria were mainly responsible for bacteremia. Fifty-five percent of enterobacteria were extended-spectrum β-lactamase (ESBL), 42% EBSL and carbapenemase, and 3% carbapenemase, with high coresistances. Eighty-four percent of A. baumannii were XDR. All P. aeruginosa were MDR; amikacin showed the best activity (70% susceptibility). The genotypic approach revealed the presence of blaCTX-M, blaSHV, blaTEM in 68%, 22%, and 11% respectively. Of the 22 carbapenemase-producers, 41% were blaOXA-48 and 18% blaNDM; none had blaVIM. Furthermore, various genes coexistence were detected: blaCTX-M+blaOXA-48; blaCTX-M+blaNDM; blaCTX-M+blaSHV+blaOXA-48; and blaSHV+blaOXA-48. findings revealed highly resistance rate among isolates. This raises the need to control antibiotics and regular screening to identify dynamics promoting resistance. Thus, we recommend developing antimicrobial stewardship programs and improving hygiene systems to prevent the nosocomial spreading of these phenotypes in our center.

A Review of In Vitro Antimicrobial Activities of Carbazole and its Derivative From 2014 to 2022

Abstract: A large number of antibiotics are easily accessible for the treatment of various micro-bial infections. However, antibiotic resistance has become a major concern to public health across the globe. Carbazole derivatives are present in carbazomycins, an unprecedented class of antibiotics showing potential antibacterial activities. As reported in the literature, carbazole de-rivatives also possess significant antimicrobial activities against bacterial resistance, such as Methicillin Resistant Staphylococcus aureus (MRSA). The antimicrobial profile of carbazole derivatives has been achieved through various bacterial pathways. Carbazole hybrids based on the multi-target direct ligand (MTDL) approach were also extensively studied as they exhibited significant antibacterial activities. This article reviews antimicrobial potential, docking analysis, and structure-activity relationship (SAR) studies of carbazole and its derivatives against tested bacterial strains from 2014 to 2022. This review can also be helpful for investigators in the de-sign and development of new molecules based on carbazole structure against various resistant bacterial infections.

Secondary Metabolites and Antimicrobial Profile of the Crude Stem and Rhizome Extracts of Lasimorpha Senegalensis (SCHOTT) Araceae

Secondary Metabolites and Antimicrobial Profile of the Crude Stem and Rhizome Extracts of Lasimorpha Senegalensis (SCHOTT) Araceae

Phenotypic antimicrobial profiling of Streptococcus spp. isolated from subclinical and clinical bovine mastitis

Phenotypic antimicrobial profiling of Streptococcus spp. isolated from subclinical and clinical bovine mastitis

Pepper-Mediated Green Synthesis of Selenium and Tellurium Nanoparticles with Antibacterial and Anticancer Potential.

The production of nanoparticles for biomedical applications (namely with antimicrobial and anticancer properties) has been significantly hampered using traditional physicochemical approaches, which often produce nanostructures with poor biocompatibility properties requiring post-synthesis functionalization to implement features that such biomedical applications require. As an alternative, green nanotechnology and the synthesis of environmentally friendly nanomaterials have been gaining attention over the last few decades, using living organisms or biomolecules derived from them, as the main raw materials to produce cost-effective, environmentally friendly, and ready-to-be-used nanomaterials. In this article and building upon previous knowledge, we have designed and implemented the synthesis of selenium and tellurium nanoparticles using extracts from fresh jalapeño and habanero peppers. After characterization, in this study, the nanoparticles were tested for both their antimicrobial and anticancer features against isolates of antibiotic-resistant bacterial strains and skin cancer cell lines, respectively. The nanosystems produced nanoparticles via a fast, eco-friendly, and cost-effective method showing different antimicrobial profiles between elements. While selenium nanoparticles lacked an antimicrobial effect at the concentrations tested, those made of tellurium produced a significant antibacterial effect even at the lowest concentration tested. These effects were correlated when the nanoparticles were tested for their cytocompatibility and anticancer properties. While selenium nanoparticles were biocompatible and had a dose-dependent anticancer effect, tellurium-based nanoparticles lacked such biocompatibility while exerting a powerful anti-cancer effect. Further, this study demonstrated a suitable mechanism of action for killing bacteria and cancer cells involving reactive oxygen species (ROS) generation. In summary, this study introduces a new green nanomedicine synthesis approach to create novel selenium and tellurium nanoparticles with attractive properties for numerous biomedical applications.

Evaluation of some o-benzenedisulfonimido–sulfonamide derivatives as potent antimicrobial agents

Background and Aims: The discovery of new antimicrobials to overcome antimicrobial resistance has always been an important topic for sustainable world health. Since the sulfonamide carrying heterocyclic compounds present a number of advantages as biologically active compounds, in our work reported herein, a small collection of previously synthesized o-benzenedisulfonimido-sulfonamide derivatives were assayed to determine antimicrobial profiles against ten different microorganisms in search of finding promising new antibacterial/antifungal agents. Methods: Eight compounds and their standards were tested against seven bacterial and three fungal strains, including members of Gram-positive, Gram-negative bacteria, and Candida spp., using the microbroth dilution method to measure their MIC (minimum inhibitory concentration) values. Results: All assayed molecules showed different inhibitory effects on ten different targets, with considerable MIC values. Particularly, compound 2 exhibited better antimicrobial activity against the largest number of assayed microorganisms. Conclusion: Further modification and development of o-benzenedisulfonimido-sulfonamide derivatives and additional in vitro studies against putative targets may result in new antimicrobial drug candidates in the near future.

Metal ions doping effect on the physicochemical, antimicrobial, and wound healing profiles of alginate-based composite

The alginate (Alg) matrix with immobilized hydroxyapatite (HAp) and zinc oxide (ZnO), cross-linked by chitosan (CS) and metal ions (Men+) Ca2+, Zn2+, and Cu2+ was created as a wound dressing. The effect of Men+ and their concentrations on water vapor transition, fluid handling, dehydration, drug release, and healing are shown. Me-containing samples have a lower sorption capacity, than a commercial Kaltostat, however, a much lower degree of their dehydration provides a longer wound wet. The Men+ presence lowers the environmental pH to slightly acidic values promoting healing. Ca2+, Zn2+, and Cu2+ in complexes with CS increase antimicrobial effect against E. coli and S. aureus, slow down the Anaesthesine release, making it compatible with Fickian diffusion in the Zn2+ and Cu2+ presence, and non-Fickian transport under Ca2+ influence. The material promotes the proliferation of the fibroblasts, an increase of collagen fibres, and new arterial and venous capillaries, indicating the intensity of the healing process.

Antimicrobial Sensitivity Profile of Mimosa pudica Leaf Extract and its Combination Treatment with Potassium Aluminum Sulphate on Some Bacteria

Mimosa pudica is a famous ornamental plant commonly known as sleeping grass, sensitive plant, humble plant, shy plant and touch-me not, among other names. The study was aimed at determining the antibacterial activity of Mimosa pudica extract in combination with alum. The plant was obtained, identified, prepared and extracted using both aqueous and methanolic medium. The extracts were reconstituted to final concentration of 250g/ml, 125g/ml, 62.5g/ml (w/v). The bacterial isolates identified were; Pseudomonas aeruginosa NC002516, Staphylococcus aureus FR821779 and Escherichia coli CP031892.1 obtained from wound source at the University of Port Harcourt Teaching Hospital and maintained in stock culture and were further confirmed using biochemical and molecular methods. In-vitro bioactivity of various concentrations of the extracts and in combination with alum were evaluated by measuring diameter of inhibition zones. From the bioassay, the combinations of the aqueous extract and alum demonstrated the highest inhibitory potential; (26.00±0.00mm) at 250g/ml for Staphylococcus aureus FR821779 and the least antibacterial effect was recorded in the consortium extract for Staphylococcus aureus FR821779; (13.00±0.00mm) at same concentration compared with other bacteria (E. coli and P. aeruginosa). The result obtained showed that all the treatments and combination treatments recorded MIC at 0.50g/ml for all the bacteria studied. The composition in percentage of the various phytochemicals were as follows: Flavanoid, 7.96±1.17%, Alkaloid, 9.85±0.21%, Saponin, 7.34±0.35% and Total-phenol, 1.63±0.00%. Alkaloids (9.85±0.21%) had the highest concentrations in the extracts while Total-phenol (1.63±0.00%) was the least in concentration. This study has been able to ascertain the sensitivity profiles of Mimosa pudica leaf extracts and its combination treatment with potassium aluminium sulphate (Alum) on some microbes specifically S. aureus, E. coli, P. aeruginosa.

Mineral contents, antimicrobial profile, acute and chronic toxicity of the aqueous extract of Moroccan Thymus vulgaris in rodents

Moroccan flora is rich in plants used in traditional medicine, but the further scientific investigation is necessary. The aim of the research was to evaluate the nutritional content and antimicrobial activity of Moroccan Thymus vulgaris, as well as its possible acute and chronic toxicological effects on rodents. Inductively coupled plasma atomic emission spectroscopy (ICP-AES) was used to determine the mineral content. The antimicrobial activity was determined using a well-diffusion test, a minimum inhibitory concentration (MIC), and a minimum bactericidal/fungicidal concentration (MBC/MFC) assay. Acute and chronic toxicity studies were conducted in vivo on mice and rats, respectively. Following that, haematological, serum-biochemistry, and histological investigations were performed. Moroccan Thyme was shown to be a source of numerous minerals which are necessary for health promotion. All antimicrobial testing, disc diffusion, MIC, and MBC tests revealed that thyme had potent antibacterial activity against all microorganisms tested. Staphylococcus aureus was the most susceptible bacterium, followed by Salmonella enterica and Escherichia coli. Additionally, thyme exhibited great antifungal efficacy against Candida albicans. The acute toxicity results indicated that the aqueous extract of T. vulgaris is almost non-toxic when taken orally. According to the chronic toxicity study, the extract is generally safe when taken orally over an extended period of time. The biochemical and haematological characteristics of the serum and blood were within acceptable limits, and histological examination revealed no abnormalities. In conclusion, the findings of this investigation, confirm the antimicrobial efficacy of the aqueous extract of Moroccan T. vulgaris and its safety for experimental animals.

Serum, saliva, and gingival tissue human β-defensin levels in relation to retinoic acid use.

Retinoic acid is an active derivative of vitamin A and regulates the differentiation, proliferation, and antimicrobial peptide expression profiles of human cells. The aim of the present study was to analyze the effect of systemic retinoic acid use on serum, saliva, and gingival tissue levels of human β-defensin (hBD)-1, hBD-2, and hBD-3. A total of 69 participants (34 systemic retinoic acid users and 35 healthy controls) were enrolled in this study. Plaque index, probing pocket depth, bleeding on probing (BOP), and clinical attachment loss were measured. Saliva and serum hBD-1, hBD-2, and hBD-3 levels were quantified by enzyme-linked immunosorbent assay. Gingival tissue hBD-1, hBD-2, and hBD-3 levels were determined by immunohistochemistry. A univariate general linear model was used in adjusted comparisons of hBD1, hBD-2, and hBD-3. P values of < 0.05 were considered statistically significant. Reduced salivary levels of hBD-2 (P = 0.042), but not hBD-1 or hBD-3, were detected in systemic retinoic acid users compared to non-user controls. There was a significant difference in the adjusted (for BOP%) salivary hBD-2 concentrations between retinoic acid and control groups (P = 0.031). No difference was observed in serum or tissue levels of hBD-1, hBD-2, or hBD-3 between the two study groups. Systemic retinoic acid use was associated with suppressed salivary hBD-2 level, which was independent of gingival inflammation.

Genomic and Evolutionary Insights into Australian Toxigenic Vibrio cholerae O1 Strains.

Vibrio cholerae O1 is the causative agent of cholera, a severe diarrheal disease which can cause death if left untreated. In this study, a collection of clinical and environmental V. cholerae serogroup O1 isolates from Australia (1977 to 1987) (from local cases and cases acquired through international travel) and publicly available international isolates were characterized for genotypic features (virulence genes, mobile genetic elements [MGEs], and antimicrobial resistance gene profiles). Whole-genome sequencing (WGS) was used to investigate and compare the genetic relatedness between the 44 Australian and nine travel-associated isolates and the 60 publicly available international V. cholerae sequences representing pre-seventh-pandemic (pre-7PET) isolates and different waves of 7PET isolates. In this study, 36 (81%) Australian clinical and aquatic isolates harbored the cholera toxin-producing genes located in the CTX bacteriophage region. All the Australian environmental and clinical isolates lacked the seventh-pandemic virulence-associated genomic islands (VSP-I and -II). In silico multilocus sequence typing (MLST) classified all nine internationally acquired isolates as sequence type 69 (ST69), 36 clinical and aquatic isolates as ST70, and eight isolates from Australia as ST71. Most of the nontoxigenic clinical and aquatic isolates of ST71 had diverse genetic variations compared to ST70 Australian strains. The antimicrobial resistance-associated genes gyrA, parC, and parE had no mutations in all the environmental and clinical isolates from Australia. The SXT genetic element and class 1 integron gene sequences were not detected in Australian strains. Moreover, in this study, a Bayesian evolutionary study suggests that two distinct lineages of ST71 (new set of strains) and ST70 strains were prevalent around similar times in Australia, in ~1973 and 1969. IMPORTANCE Australia has its own indigenous V. cholerae strains, both toxigenic and nontoxigenic, that are associated with disease. Exotic strains are also detected in Australian patients returning from overseas travel. The clinical and aquatic V. cholerae O1 toxin gene-positive isolates from Australia responsible for cases in 1977 to 1987 were linked to acquisition from Queensland waterways but until now had not been characterized genetically. It is important to determine the genetic relatedness of Australian strains to international strains to assist in understanding their origin. This is the first extensive study to provide sequences and genomic analysis focused on toxigenic O1 V. cholerae clinical and environmental strains from Australia and its possible evolutionary relationship with other publicly available pre-7PET and 7PET V. cholerae strains. It is important to understand the population genetics of Australian V. cholerae from a public health perspective to assist in devising control measures and management plans for reducing V. cholerae exposure in Australia, given previous Australian disease clusters.