Future microbiology最新文献

Objective: The antimicrobial activities of the synergistic combination of carvacrol and polymyxin B against polymyxin-resistant Klebsiella pneumoniae were evaluated. Methods: The methods employed checkerboard assays to investigate synergism, biofilm inhibition assessment and membrane integrity assay. In addition, the study included in vivo evaluation using a mouse infection model. Results: The checkerboard method evaluated 48 combinations, with 23 indicating synergistic action. Among these, carvacrol 10 mg/kg plus polymyxin B 2 mg/kg exhibited in vivo antimicrobial activity in a mouse model of infection, resulting in increased survival and a significant decrease in bacterial load in the blood. Conclusion: Polymyxin in synergy with carvacrol represents a promising alternative to be explored in the development of new antimicrobials.

Sulbactam-durlobactam is a pathogen-targeted β-lactam/β-lactamase inhibitor combination that has been approved by the US FDA for the treatment of hospital-acquired and ventilator-associated bacterial pneumonia caused by susceptible isolates of Acinetobacter baumannii-calcoaceticus complex (ABC) in patients 18 years of age and older. Sulbactam is a penicillin derivative with antibacterial activity against Acinetobacter but is prone to hydrolysis by β-lactamases encoded by contemporary isolates. Durlobactam is a diazabicyclooctane β-lactamase inhibitor with activity against Ambler classes A, C and D serine β-lactamases that restores sulbactam activity both in vitro and in vivo against multidrug-resistant ABC. Sulbactam-durlobactam is a promising alternative therapy for the treatment of serious Acinetobacter infections, which can have high rates of mortality.

Background: Staphylococcus aureus is a human pathogen responsible for high mortality rates. The development of new antimicrobials is urgent. Materials & methods: The authors evaluated the activity of hydralazine along with its synergism with other drugs and action on biofilms. With regard to action mechanisms, the authors evaluated cell viability, DNA damage and molecular docking. Results: MIC and minimum bactericidal concentration values ranged from 128 to 2048 μg/ml. There was synergism with oxacillin (50%) and vancomycin (25%). Hydralazine reduced the viability of biofilms by 50%. After exposure to hydralazine 2× MIC, 58.78% of the cells were unviable, 62.07% were TUNEL positive and 27.03% presented damage in the comet assay (p < 0.05). Hydralazine showed affinity for DNA gyrase and TyrRS. Conclusion: Hydralazine is a potential antibacterial.

Aim: Mycoplasma pneumoniae (MP) is a common cause of respiratory infections, and its incidence has increased post-COVID-19 due to "immune debt." Real-time quantitative polymerase chain reaction (qPCR) is the standard for detecting MP, but it has a lengthy detection time. This study aimed to establish a highly sensitive rapid detection method for MP.Materials & methods: We developed an integrated assay combining multienzyme isothermal rapid amplification (MIRA) with qPCR, referred to as MIRA-qPCR, for the rapid detection of MP, delivering results within approximately 40 min.Results: The analytic sensitivity of the MIRA-qPCR assay was 10 copies per reaction, and it exhibited no cross-reactivity with other respiratory pathogens, ensuring high specificity. Clinical sample analysis demonstrated higher sensitivity for MIRA-qPCR compared to qPCR reported in the literature, and 100% concordance with commercial qPCR kit.Conclusion: The MIRA-qPCR method established in this study is a promising tool for the clinical detection of MP, offering significant advantages for the rapid diagnosis of MP infections.

Diverse microorganisms live as biofilm in the mouth accounts for oral diseases and treatment failure. For decades, the prevention and treatment of oral biofilm is a global challenge. Antimicrobial photodynamic therapy (aPDT) holds promise for oral biofilm elimination due to its several traits, including broad-spectrum antimicrobial capacity, lower possibility of resistance and low cytotoxicity. However, the physicochemical properties of photosensitizers and the biological barrier of oral biofilm have limited the efficiency of aPDT. Nanomaterials has been used to fabricate nanocarriers to improve photosensitizer properties and thus enhance antimicrobial effect. In this review, we have discussed the challenges of aPDT used in dentistry, categorized the nanomaterial-delivery system and listed the possible mechanisms involved in nanomaterials when enhancing aPDT effect.

Hospital-acquired bacterial pneumonia (HABP) and ventilator-associated bacterial pneumonia (VABP) are common healthcare-associated infections linked to high morbidity and mortality. Gram-negative pathogens, such as Pseudomonas aeruginosa, exhibit multidrug resistance and are recognized as major public health concerns, particularly among critically ill patients with HABP/VABP. Ceftolozane/tazobactam is a novel combination antibacterial agent comprising ceftolozane (a potent antipseudomonal cephalosporin) and tazobactam (a β-lactamase inhibitor). Phase III trials have demonstrated non-inferiority of ceftolozane/tazobactam to comparators, leading to the approval of ceftolozane/tazobactam for the treatment of complicated urinary tract infections, complicated intra-abdominal infections, and nosocomial pneumonia. In this article, we review the clinical trial evidence and key real-world effectiveness data of ceftolozane/tazobactam for the treatment of serious healthcare-associated Gram-negative infections, focusing on patients with HABP/VABP.

Ferroptosis, known as a type of programmed cell death that is iron dependent, is characterized by intracellular iron accumulation, glutathione depletion, glutathione peroxidase inactivation and lipid peroxidation. More and more research in recent years has demonstrated the tight connection between viral infections and ferroptosis. This article reviews the potential role and mechanism of ferroptosis in viral infection, and these findings will help in the prevention and treatment of the virus.

Aim: To explore the antifungal potential of Sanghuang mushroom, a traditional Chinese medicine. Materials & methods: The antifungal properties and the potential mechanism of Sanghuang mushroom extracts against Candida albicans were studied in vitro and in vivo. Results: Sanghuang mushroom extracts inhibited the biofilm formation, increased the cell membrane permeability and promoted cell apoptosis of C. albicans in vitro. In a murine model of vulvovaginal candidiasis, Sanghuang mushroom extracts reduced the vaginal fungal load, improved inflammatory cell infiltration and downregulated the expression of TNF-α, IL-1β and IL-6. Untargeted metabolomic analysis suggested the presence of ten antifungal components in Sanghuang mushroom extracts. Conclusion: Sanghuang mushroom extracts showed promise as antifungal agent against candidiasis, with potential therapeutic implications.

Aim: Mucormycosis has been associated with SARS-CoV-2 infections during the last year. The aim of this study was to triple-hit viral and fungal RNA-dependent RNA polymerases (RdRps) and human inosine monophosphate dehydrogenase (IMPDH). Materials & methods: Molecular docking and molecular dynamics simulation were used to test nucleotide inhibitors (NIs) against the RdRps of SARS-CoV-2 and Rhizopus oryzae RdRp. These same inhibitors targeted IMPDH. Results: Four NIs revealed a comparable binding affinity to the two drugs, remdesivir and sofosbuvir. Binding energies were calculated using the most abundant conformations of the RdRps after 100-ns molecular dynamics simulation. Conclusion: We suggest the triple-inhibition potential of four NIs against pathogenic RdRps and IMPDH, which is worth experimental validation.

Background: Aerococcus urinae and Aerococcus sanguinicola are emerging pathogens linked with urinary tract infections. We present a case series of A. urinae and A. sanguinicola isolates characterizing the spectrum of clinical presentation, microbiological characteristics and antimicrobial sensitivities.Methods: Retrospective chart review was performed on patients who grew positive cultures for A. urinae and A. sanguinicola identified on MALDI-TOF in Saskatchewan from January to June 2023. Demographic and clinical variables, antimicrobial susceptibility and prescription were documented.Results: This cohort (n = 115) had a median age 82 years. A. urinae and A. sanguinicola infections spanned from urinary tract infection (n = 96) to urosepsis (n = 6). These infections were predominantly monomicrobial (73.9%) and were susceptible to ceftriaxone, penicillin G and vancomycin. Antimicrobials were seldom prescribed within the urinary tract infection cohort (31.2%).Conclusion: Untreated A. urinae and A. sanguinicola infections can precipitate into urosepsis. The reported antimicrobial susceptibility for these Aerococcus isolates should be utilized to provide appropriate antimicrobial coverage.