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International Wound Journal Apr 2024Multidrug-resistant (MDR) bacterial infections have become increasingly common in recent years due to the increased prevalence of diabetic foot ulcers (DFUs). We carried... (Meta-Analysis)
Meta-Analysis
Multidrug-resistant (MDR) bacterial infections have become increasingly common in recent years due to the increased prevalence of diabetic foot ulcers (DFUs). We carried out a meta-analysis aimed at investigating the prevalence of MDR bacteria isolated from DFUs and analysing the risk factors for MDR bacterial infection in patients with DFUs. The PubMed/Medline, Web of Science, Embase, Cochrane Library, Ovid, Scopus, and ProQuest databases were searched for studies published up to November 2023 on the clinical outcomes of MDR bacteria in DFUs. The main outcome was the prevalence of MDR bacteria in DFUs. A total of 21 studies were included, representing 4885 patients from which 2633 MDR bacterial isolates were obtained. The prevalence of MDR bacteria in DFUs was 50.86% (95% confidence interval (CI): 41.92%-59.78%). The prevalence of MDR gram-positive bacteria (GPB) in DFUs was 19.81% (95% CI: 14.35%-25.91%), and the prevalence of MDR gram-negative bacteria (GNB) in DFUs was 32.84% (95% CI: 26.40%-39.62%). MDR Staphylococcus aureus (12.13% (95% CI: 8.79%-15.91%)) and MDR Enterococcus spp. (3.33% (95% CI: 1.92%-5.07%)) were the main MDR-GPB in DFUs. MDR Escherichia coli, MDR Pseudomonas aeruginosa, MDR Enterobacter spp., MDR Klebsiella pneumoniae, and MDR Proteus mirabilis were the main MDR-GNB in DFUs. The prevalence rates were 6.93% (95% CI: 5.15%-8.95%), 6.01% (95% CI: 4.03%-8.33%), 3.59% (95% CI: 0.42%-9.30%), 3.50% (95% CI: 2.31%-4.91%), and 3.27% (95% CI: 1.74%-5.21%), respectively. The clinical variables of diabetic foot ulcer patients infected with MDR bacteria and non-MDR bacteria in the included studies were analysed. The results showed that peripheral vascular disease, peripheral neuropathy, nephropathy, osteomyelitis, Wagner's grade, previous hospitalization and previous use of antibacterial drugs were significantly different between the MDR bacterial group and the non-MDR bacterial group. We concluded that there is a high prevalence of MDR bacterial infections in DFUs. The prevalence of MDR-GNB was greater than that of MDR-GPB in DFUs. MDR S. aureus was the main MDR-GPB in DFUs, and MDR E. coli was the main MDR-GNB in DFUs. Our study also indicated that peripheral vascular disease, peripheral neuropathy, nephropathy, osteomyelitis, Wagner's grade, previous hospitalization, and previous use of antibacterial drugs were associated with MDR bacterial infections in patients with DFUs.
Topics: Humans; Diabetic Foot; Escherichia coli; Prevalence; Staphylococcus aureus; Anti-Bacterial Agents; Osteomyelitis; Peripheral Vascular Diseases; Bacterial Infections; Diabetes Mellitus
PubMed: 38619084
DOI: 10.1111/iwj.14864 -
Journal of Veterinary Internal Medicine 2023Pseudomembranous cystitis (PMC) in cats is a recognized disease, but concurrent mineralization is reported rarely and its outcome is poorly described.
BACKGROUND
Pseudomembranous cystitis (PMC) in cats is a recognized disease, but concurrent mineralization is reported rarely and its outcome is poorly described.
HYPOTHESIS AND OBJECTIVES
Describe a population of cats with PMC and the prevalence of concurrent mineralization.
ANIMALS
Twenty-six cats with PMC.
METHODS
Medical records were retrospectively reviewed (January 2016 to December 2021). Cats with an ultrasound diagnosis of PMC were included. Clinicopathologic results, imaging, treatment, and outcome were reviewed.
RESULTS
All cats were male and 21 (80%) were diagnosed with urethral obstruction (UO). Five cats (23.8%) had positive urine culture (Staphylococcus felis, 3/5; Proteus mirabilis, 2/5) with a median urine pH of 8 (range, 6-9). All cats had ultrasonographic changes suggestive of mineralization. On ultrasound examination, 10 cats (38.5%) had pseudomembranes with acoustic shadowing suggestive of mineralization, 15 (57.7%) had changes indicative of ulceration, and 8 (31%) had changes compatible with of a urachal anomaly. Twenty-two cats received medical treatment, 4 underwent surgery (3 percutaneous cystolithotomy, 1 cystotomy). Twenty cats (77%) survived to discharge. Follow-up ultrasound examination indicated resolution of PMC in 6/7 cats, 4 had persistent hyperechoic bladder lining. Five of 12 cats with follow-up had a relapse of lower urinary tract signs.
CONCLUSIONS AND CLINICAL IMPORTANCE
Pseudomembranous cystitis was diagnosed mainly in male cats with UO and imaging findings suggestive of mineralization were present in all cases. Frequent negative urine culture suggests a different etiology than encrusting cystitis related to urease-positive bacteria. Good outcomes can be achieved with medical management.
Topics: Cats; Male; Animals; Female; Retrospective Studies; Cystitis; Urinary Bladder; Urinary Bladder Calculi; Urethral Obstruction; Cat Diseases
PubMed: 37497780
DOI: 10.1111/jvim.16819 -
Journal of Bacteriology Apr 2024A hallmark of infection of the urinary tract is the formation of stones. The ability to induce urinary stone formation requires urease, a nickel metalloenzyme that...
UNLABELLED
A hallmark of infection of the urinary tract is the formation of stones. The ability to induce urinary stone formation requires urease, a nickel metalloenzyme that hydrolyzes urea. This reaction produces ammonia as a byproduct, which can serve as a nitrogen source and weak base that raises the local pH. The resulting alkalinity induces the precipitation of ions to form stones. Transcriptional regulator UreR activates expression of urease genes in a urea-dependent manner. Thus, urease genes are highly expressed in the urinary tract where urea is abundant. Production of mature urease also requires the import of nickel into the cytoplasm and its incorporation into the urease apoenzyme. Urease accessory proteins primarily acquire nickel from one of two nickel transporters and facilitate incorporation of nickel to form mature urease. In this study, we performed a comprehensive RNA-seq to define the urea-induced transcriptome as well as the UreR regulon. We identified UreR as the first defined regulator of nickel transport in . We also offer evidence for the direct regulation of the Ynt nickel transporter by UreR. Using bioinformatics, we identified UreR-regulated urease loci in 15 family species across three genera. Additionally, we located two mobilized UreR-regulated urease loci that also encode the transporter, implying that UreR regulation of nickel transport is a conserved regulatory relationship. Our study demonstrates that UreR specifically regulates genes required to produce mature urease, an essential virulence factor for uropathogenesis.
IMPORTANCE
Catheter-associated urinary tract infections (CAUTIs) account for over 40% of acute nosocomial infections in the USA and generate $340 million in healthcare costs annually. A major causative agent of CAUTIs is , an understudied Gram-negative pathogen noted for its ability to form urinary stones via the activity of urease. Urease mutants cannot induce stones and are attenuated in a murine UTI model, indicating this enzyme is essential to pathogenesis. Transcriptional regulation of urease genes by UreR is well established; here, we expand the UreR regulon to include regulation of nickel import, a function required to produce mature urease. Furthermore, we reflect on the role of urea catalysis in metabolism and provide evidence for its importance.
Topics: Animals; Mice; Proteus mirabilis; Urease; Nickel; Bacterial Proteins; Escherichia coli; Urinary Tract Infections; Urea; Proteus Infections
PubMed: 38534115
DOI: 10.1128/jb.00031-24 -
Brazilian Journal of Microbiology :... Dec 2023The rate of infectious diseases started to be one of the major mortality agents in the healthcare sector. Exposed to increased bacterial infection by...
Assignment of the antibacterial potential of AgO/ZnO nanocomposite against MDR bacteria Proteus mirabilis and Salmonella typhi isolated from bone marrow transplant patients.
The rate of infectious diseases started to be one of the major mortality agents in the healthcare sector. Exposed to increased bacterial infection by antibiotic-resistant bacteria became one of the complications that occurred for bone marrow transplant patients. Nanotechnology may provide clinicians and patients with the key to overcoming multidrug-resistant bacteria. Therefore, this study was conducted to clarify the prevalence of MDR bacteria in bone marrow transplant recipients and the use of AgO/ZnO nanocomposites to treat participants of diarrhea brought on by MDR bacteria following bone marrow transplantation (BMT). Present results show that pathogenic bacteria were present in 100 of 195 stool samples from individuals who had diarrhea. Phenotypic, biochemical, and molecular analysis clarify that Proteus mirabilis and Salmonella typhi were detected in 21 and 25 samples, respectively. Successful synthesis of AgO/ZnO nanocomposites with a particle enables to inhibition of both pathogens. The maximum inhibitory impact was seen on Salmonella typhi. At low doses (10 g/l), it prevented the growth by 53.4%, while at higher concentrations (10 g/l), Salmonella typhi was inhibited by 95.5%. Regarding Proteus mirabilis, at (10 g/l) AgO/ZnO, it was inhabited by 78.7%, but at higher concentrations (10 g/l), it was inhibited the growth by 94.6%. AgO/ZnO nanocomposite was therefore found to be the most effective therapy for MDR-isolated bacteria and offered promise for the treatment of MDR bacterial infections that cause diarrhea.
Topics: Humans; Proteus mirabilis; Salmonella typhi; Zinc Oxide; Bone Marrow; Bone Marrow Transplantation; Anti-Bacterial Agents; Bacteria; Diarrhea
PubMed: 37801221
DOI: 10.1007/s42770-023-01138-4 -
Molecules (Basel, Switzerland) Oct 2023The aim of this study was to investigate the compounds in the hexane extract of (Savi.) Ten. and to determine the antibacterial, antifungal, and antioxidant activities...
The aim of this study was to investigate the compounds in the hexane extract of (Savi.) Ten. and to determine the antibacterial, antifungal, and antioxidant activities of different extracts. The (NGBB 7229) plant was collected from Turkey's Trakya region. Crude extracts were obtained using different solvents. The chemical composition of was determined in hexane extract using gas chromatography mass spectrometry. The antioxidant activities of the extracts were evaluated by Trolox equivalent antioxidant activity (TEAC), ferric-reducing antioxidant power (FRAP), cupric-reducing antioxidant capacity (CUPRAC), the β-carotene bleaching method, and the determination of superoxide anion scavenging activities. The antibacterial activity was tested against , , , , , and , whereas the antifungal activity was tested against , , and by applying microdilution methods. A total of 41 bioactive compounds were identified using the GC-MS library. Terpenoids were found to be dominant (52.89%), and lup-20(29)-en-3-yl-acetate and lupeol were the most abundant terpenoids. The highest total flavonoid content (25.73 mg catechin/g) and antioxidant capacity were found in the methanolic extract. The highest antibacterial activity was detected against in the ethyl acetate extract, and the highest antifungal activity was found against and in the hexane extract. The observed antioxidant characteristics of the extracts could be attributed to the presence of flavonoids. The high antifungal activity of the hexane extract against all fungal strains can be attributed to its constituents, i.e., terpenoids. This study discloses the potential antioxidant and antimicrobial activities, including some bioactive components, of and implies that holds possible applications in the food and pharmaceutical industries as an antioxidant, antibacterial, and antifungal agent.
Topics: Antioxidants; Antifungal Agents; Cirsium; Hexanes; Plant Extracts; Anti-Infective Agents; Anti-Bacterial Agents; Flavonoids; Terpenes; Candida albicans
PubMed: 37894654
DOI: 10.3390/molecules28207177 -
BMC Research Notes Jan 2024Proteus mirabilis is related to serious infections. The present study was designed to investigate the minimum inhibitory concentration (MIC) of silver nanoparticles...
Determining the cytotoxicity of the Minimum Inhibitory Concentration (MIC) of silver and zinc oxide nanoparticles in ESBL and carbapenemase producing Proteus mirabilis isolated from clinical samples in Shiraz, Southwest Iran.
OBJECTIVE
Proteus mirabilis is related to serious infections. The present study was designed to investigate the minimum inhibitory concentration (MIC) of silver nanoparticles (AgNPs) and zinc oxide nanoparticles (ZnONPs) and cytotoxicity among P. mirabilis isolates recovered from clinical samples in Shiraz.
RESULTS
A total of 100 P. mirabilis isolates were screened by biochemical tests and polymerase chain reaction (PCR). Also, 25 (25%) and 7 (7%) isolates were positive for extended-spectrum beta-lactamase (ESBLs) and carbapenemase, respectively. Synthesized nanoparticles were characterized by UV-vis spectrum, X-ray diffraction (XRD), and electron microscopy. The average size of AgNPs and ZnONPs in the present study is 48 and < 70 nm, respectively. The MIC and the MBC of the ZnONPs were in the range of 31.25 µg/ml and 62.5 µg/mL, respectively. Also, for AgNPs, the MIC and the MBC were in the range of 7.8 µg/mL and 15.6 µg/mL, respectively. MTT (3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay in a primary culture of fibroblast L929 cells for this MIC indicated biocompatibility and low cytotoxicity of Ag NPs and for ZnONPs indicated significant cytotoxicity. Also, a MIC of AgNPs can be used as a therapeutic concentration without the effect of cytotoxicity in human cells.
Topics: Humans; Silver; Anti-Bacterial Agents; Zinc Oxide; Proteus mirabilis; Metal Nanoparticles; Iran; Microbial Sensitivity Tests; Bacterial Proteins; beta-Lactamases
PubMed: 38287416
DOI: 10.1186/s13104-023-06402-2 -
Molecules (Basel, Switzerland) Jul 2023A series of novel Mannich bases were designed, synthesized, and screened for their antimicrobial activity. The target compounds were synthesized from...
A series of novel Mannich bases were designed, synthesized, and screened for their antimicrobial activity. The target compounds were synthesized from 4-(3-chlorophenyl)-5-(3-fluorophenyl)-2,4-dihydro-3-1,2,4-triazole-3-thione and different piperazine derivatives. The structures of the products were confirmed by H and C NMR and elemental analysis. The activity of piperazine derivatives against bacteria (Gram-positive: , , , , and ; Gram-negative: , , , and ) and yeasts (, , and ) was determined by the minimum inhibitory concentration and minimum bactericidal concentration values. Significant activity was observed against Gram-positive bacteria, mainly staphylococci (-) and bacteria of the genes of and (), as well as selected strains of Gram-negative bacteria, including bacteria of the family (), while all tested compounds showed high fungistatic activity against spp. yeasts, especially , with MICs ranging from 0.49 µg/mL () to 0.98 µg/mL () and 62.5 µg/mL (). In conclusion, the results obtained confirm the multidirectional antimicrobial activity of the newly synthesized piperazine derivatives. Furthermore, in silico studies suggest that the tested compounds are likely to have good oral bioavailability. The results obtained will provide valuable data for further research into this interesting group of compounds. The library of compounds obtained is still the subject of pharmacological research aimed at finding new interesting biologically active compounds.
Topics: Piperazine; Mannich Bases; Bacteria; Gram-Positive Bacteria; Microbial Sensitivity Tests; Gram-Negative Bacteria; Candida; Anti-Infective Agents; Anti-Bacterial Agents
PubMed: 37513434
DOI: 10.3390/molecules28145562 -
Skin Health and Disease Jun 2024Incontinence Associated Dermatitis (IAD) is a type of skin inflammation caused by chronic exposure to urine and/or faeces. Current treatment strategies involve creating...
BACKGROUND
Incontinence Associated Dermatitis (IAD) is a type of skin inflammation caused by chronic exposure to urine and/or faeces. Current treatment strategies involve creating a barrier between the skin and urine/faeces rather than targeting specific irritants. Urease expressing pathogens catalyse the conversion of urea, present in urine, into ammonia. The accumulation of ammonia causes an elevation in skin pH which is believed to activate faecal enzymes which damage skin, and opportunistic pathogens, which lead to secondary infections.
OBJECTIVES
To develop a better, multi-factorial model of IAD pathogenesis, including the effect of urease-expressing bacteria on skin, mechanism of damage of urease and urease-triggered activity of faecal enzymes and secondary pathogens. To study the effect of urease inhibition on preventing IAD skin damage.
METHODS
Five separate studies were made using ex vivo porcine skin and in vivo human skin models. Measurements of the change in skin barrier function were made using skin impedance, trans-epidermal water loss (TEWL), stratum corneum moisture and pH. Skin was exposed to artificial urine, inoculated with various microbes, enzymes and chemicals to examine the influence of: 1) urease-positive 2) ammonia, 3) combination of and a faecal enzyme, trypsin, 4) combination of and opportunistic pathogens, and , 5) inhibition of urease using acetohydroxamic acid (AHA) on barrier function.
RESULTS
The urease-mediated production of ammonia had two principal effects: it elevated skin pH and caused inflammation, leading to significant breakdown in skin (stratum corneum) barrier function. Urease was found to further increase the activity of faecal enzymes and opportunistic pathogens, due to elevated skin pH. The urease inhibitor, AHA, was shown to have significantly reduced damage to skin barrier function, measured as its electrical resistance.
CONCLUSIONS
Targeted therapeutic strategies should be developed to prevent the manifestation of IAD, rather than creating a generic barrier between skin and urine/faeces. Urease has been identified as a crucial component in the manifestation of IAD, due to its role in the production of ammonia. Urease inhibition provides a promising therapeutic target to halt the progression of IAD.
PubMed: 38846694
DOI: 10.1002/ski2.349 -
Journal of Biomolecular Structure &... Oct 2023This report examines the bio-fabrication of silver nanoparticles (Ag-NPs) utilizing AgNO and leaf extract of as the precursor material. In order to maximize the...
This report examines the bio-fabrication of silver nanoparticles (Ag-NPs) utilizing AgNO and leaf extract of as the precursor material. In order to maximize the antibacterial efficacy against , , and , the reaction conditions for the green fabrication of Ag-NPs were optimized. A one factor at a time approach (volume concentration of extract, volume concentration of AgNO, pH and temperature) was used to optimize the best condition, and results were assessed through UV-visible spectroscopy and particle size distribution. The results showed that 20 mL of plant extract, 80 mL of AgNO, pH 08, 100 °C temperature were the optimum reaction conditions under which we obtained the smallest Ag-NPs (7 nm). The scanning electron microscopy and X-ray diffraction analysis confirmed the spherical and crystalline nature of Ag-NPs. The antibacterial activity assay demonstrated a high antibacterial effect of Ag-NPs against , , and , and that impact was greater with smaller-sized nanoparticles (7 nm). This study shows that leaf extract of is a possible medium for the green fabrication of Ag-NPs, and control over reaction factors can establish the characteristics and antibacterial effectiveness of Ag-NPs.Communicated by Ramaswamy H. Sarma.
PubMed: 37793992
DOI: 10.1080/07391102.2023.2242960 -
Microbiology Spectrum Feb 2024can transfer transposons, insertion sequences, and gene cassettes to the chromosomes of other hosts through SXT/R391 integrative and conjugative elements (ICEs),...
can transfer transposons, insertion sequences, and gene cassettes to the chromosomes of other hosts through SXT/R391 integrative and conjugative elements (ICEs), significantly increasing the possibility of antibiotic resistance gene (ARG) evolution and expanding the risk of ARGs transmission among bacteria. A total of 103 strains of were isolated from 25 farms in China from 2018 to 2020. The positive detection rate of SXT/R391 ICEs was 25.2% (26/103). All SXT/R391 ICEs positive exhibited a high level of overall drug resistance. Conjugation experiments showed that all 26 SXT/R391 ICEs could efficiently transfer to EC600 with a frequency of 2.0 × 10 to 6.0 × 10. The acquired ARGs, genetic structures, homology relationships, and conservation sequences of 26 (19 different subtypes) SXT/R391 ICEs were investigated by high-throughput sequencing, whole-genome typing, and phylogenetic tree construction. ICEChnHBRJC2 carries ), which have never been found within an SXT/R391 ICE in , and ICEChnSC1111 carries 19 ARGs, including clinically important , , and , making it the ICE with the most ARGs reported to date. Through genetic stability, growth curve, and competition experiments, it was found that the transconjugant of ICEChnSCNNC12 did not have a significant fitness cost on the recipient bacterium EC600 and may have a higher risk of transmission and dissemination. Although the transconjugant of ICEChnSCSZC20 had a relatively obvious fitness cost on EC600, long-term resistance selection pressure may improve bacterial fitness through compensatory adaptation, providing scientific evidence for risk assessment of horizontal transfer and dissemination of SXT/R391 ICEs in .IMPORTANCEThe spread of antibiotic resistance genes (ARGs) is a major public health concern. The study investigated the prevalence and genetic diversity of integrative and conjugative elements (ICEs) in , which can transfer ARGs to other hosts. The study found that all of the strains carrying ICEs exhibited a high level of drug resistance and a higher risk of transmission and dissemination of ARGs. The analysis of novel multidrug-resistant ICEs highlighted the potential for the evolution and spread of novel resistance mechanisms. These findings emphasize the importance of monitoring the spread of ICEs carrying ARGs and the urgent need for effective strategies to combat antibiotic resistance. Understanding the genetic diversity and potential for transmission of ARGs among bacteria is crucial for developing targeted interventions to mitigate the threat of antibiotic resistance.
Topics: Proteus mirabilis; Phylogeny; Conjugation, Genetic; Drug Resistance, Multiple; DNA Transposable Elements; Anti-Bacterial Agents; Escherichia coli; Risk Assessment
PubMed: 38197656
DOI: 10.1128/spectrum.01209-23