Peptidoglycan binding protein (PGBP)-modified magnetic nanobeads for efficient magnetic capturing of Staphylococcus aureus associated with sepsis in blood

Immunomodulation in Non-traditional Therapies for Methicillin-resistant Staphylococcus aureus (MRSA) Management

The rise of methicillin-resistant Staphylococcus aureus (MRSA) poses a significant challenge in clinical settings due to its ability to evade conventional antibiotic treatments. This overview explores the potential of immunomodulatory strategies as alternative therapeutic approaches to combat MRSA infections. Traditional antibiotics are becoming less effective, necessitating innovative solutions that harness the body's immune system to enhance pathogen clearance. Recent advancements in immunotherapy, including the use of antimicrobial peptides, phage therapy, and mechanisms of immune cells, demonstrate promise in enhancing the body's ability to clear MRSA infections. However, the exact interactions between these therapies and immunomodulation are not fully understood, underscoring the need for further research. Hence, this review aims to provide a broad overview of the current understanding of non-traditional therapeutics and their impact on immune responses, which could lead to more effective MRSA treatment strategies. Additionally, combining immunomodulatory agents with existing antibiotics may improve outcomes, particularly for immunocompromised patients or those with chronic infections. As the landscape of antibiotic resistance evolves, the development of effective immunotherapeutic strategies could play a vital role in managing MRSA infections and reducing reliance on traditional antibiotics. Future research must focus on optimizing these approaches and validating their efficacy in diverse clinical populations to address the urgent need for effective MRSA management strategies.

Diabetic wound healing approaches: an update

Diabetic wounds are of profound clinical importance. Despite immense efforts directed towards its management, it results in the development of amputations, following a diagnosis of diabetic foot. With a better understanding of the complexities of the microbalance involved in the healing process, researchers have developed advanced methods for the management of wounds as well as diagnostic tools (especially, for wound infections) to be delivered to clinics sooner. In this review, we address the newer developments that hope to drive the transition from bench to bedside in the coming decade.

Phage derived lytic peptides, a secret weapon against Acinetobacter baumannii-An in silico approach

Acinetobacter baumannii is a bacterial pathogen that is commonly associated with hospital-acquired illnesses. Antimicrobial drug resistance in A. baumannii includes several penicillin classes, first and second-generation cephalosporins, cephamycins, most aminoglycosides, chloramphenicol, and tetracyclines. The recent rise in multidrug-resistant A. baumannii strains has resulted in an increase in pneumoniae associated with ventilators, urinary tract infections associated with the catheter, and bloodstream infections, all of which have increased complications in treatment, cost of treatment, and death. Small compounds known as antimicrobial peptides (AMPs) are known to have damaging effects on pathogenic bacteria. To determine their antimicrobial activity, AMPs are created from proteins acquired from various sources and evaluated in vitro. In the last phase of lytic cycle, bacteriophages release hydrolytic enzymes called endolysins that cleave the host's cell wall. Due to their superior potency and specificity compared to antibiotics, lysins are used as antibacterial agents. In the present study, different types of endolysin from phages of A. baumannii were selected based on an extensive literature survey. From the PhaLP database, the sequences of the selected lysins were retrieved in FASTA format and antimicrobial peptides were found among them. With the help of available bioinformatic tools, the anti-biofilm property, anti-fungal property, cell-penetrating property, and cellular toxicity of the antimicrobial peptides were determined. Out of the fourteen antimicrobial peptides found from the eight selected endolysins of A. baumannii specific phage, eight of them has anti-biofilm property, nine of them has anti-fungal property, five of them has cell-penetrating property and all of them are non-toxic.

Nomogram for Risk Prediction of Mortality for Patients with Critical Cardiovascular Disease Treated by Continuous Renal Replacement Therapy in Coronary Care Unit

Aims

To establish a nomogram-scoring model for evaluating the risk of death in patients with critical cardiovascular disease after continuous renal replacement therapy (CRRT) in a coronary care unit (CCU).

Methods

This retrospective cohort study included data collected on 172 patients, in whom CRRT was initiated in the CCU between January 2017 and June 2021. Predictors of mortality were selected using an adaptive least absolute shrinkage and selection operator logistic model and used to construct a nomogram. The nomogram was evaluated using the concordance index (C-index) and Hosmer-Lemeshow test.

Results

The number of patients who died in-hospital after CRRT was 91 (52.9%). The results of the multivariate logistic regression analyses clarified that age, history of hypertension and/or coronary artery bypass grafting, a diagnosis of unstable angina pectoris or acute myocardial infarction, ejection fraction, systolic blood pressure, creatinine, neutrophil, and platelet counts before CRRT initiation were significant predictors of early mortality in patients treated with CRRT. The nomogram constructed on these predictors demonstrated significant discriminative power with an unadjusted C-index of 0.902 (95% CI: 0.858-0.945) and a bootstrap-corrected C-index of 0.875. Visual inspection showed a good agreement between actual and predicted probabilities (Hosmer-Lemeshow χ 2 = 5.032, p-value = 0.754).

Conclusions

Our nomogram based on nine readily available predictors is a reliable and convenient tool for identifying critical patients undergoing CRRT at risk of mortality in the CCU.

Biomolecules capturing live bacteria from clinical samples

Rapid phenotypic antimicrobial susceptibility testing (AST) requires the enrichment of live bacteria from patient samples, which is particularly challenging in the context of life-threatening bloodstream infections (BSIs) due to low bacterial titers. Over two decades, an extensive array of pathogen-specific biomolecules has been identified to capture live bacteria. The prevailing biomolecules are immune proteins of the complement system, antibodies, aptamers, phage proteins, and antimicrobial peptides. These biomolecules differ by their binder generation technologies and exhibit highly variable specificities, ranging from bacterial strains to most pathogenic bacteria. Here, we summarize how these diverse biomolecules were identified, list examples of successfully reported capture assays, and provide an outlook on the use of nanobodies raised against conserved surface-accessible proteins as promising biomolecules for pathogen capture.

Efficacy and prognosis of continuous renal replacement therapy at different times in the treatment of patients with sepsis-induced acute kidney injury

OBJECTIVE

To investigate the efficacy and prognosis of CRRT at different times in the treatment of sepsis-induced acute kidney injury (SAKI).

METHODS

A total of 156 patients with SAKI were grouped into two groups in accordance with a random number table, with 78 patients in each group. Patients in the observation group (OG) were treated with early CRRT, and in the control group (CG), patients were treated with delayed CRRT. According to whether the patients died, there were 51 cases in the death group and 105 in the survival group. Renal function and inflammatory factors were compared before and after treatment; univariate and multilateral comparison were conducted to analyze the survival status of the patients.

RESULTS

After treatment, the blood urea nitrogen (BUN) and serum creatinine (Scr) in both groups fell below those prior to treatment, while the estimated glomerular filtration rate (eGFR) was elevated (P<0.01); the decrease of BUN and Scr in the OG was greater than that of the other group, while increase eGFR was more than that the other group (P<0.01). After treatment, C-reactive protein (CRP), tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) in both groups decreased compared to that prior to treatment (P<0.001); the decrease of the three factors in the OG was greater than that in the CG (P<0.05). The 60-day survival rate of patients in the OG was 76.92%, which was higher that of 57.69% in the CG (P<0.05). The age, acute physiology and chronic health enquiry (APACHE-II) score and proportion of chronic obstructive pulmonary disease (COPD) in the death group was elevated compared to those in the survival group, while the number of patients with early CRRT and eGFR level before treatment were lower than those in the survival group (P<0.05). Age was an independent risk factor for the prognosis of SAKI, and early CRRT was a protective factor for the prognosis (P<0.05).

CONCLUSION

Early CRRT for SAKI can improve the renal function and inflammatory state effectively, and reduce the mortality of patients. Age is an independent risk factor affecting the prognosis of patients with SAKI, and early CRRT is a protective factor for the prognosis.

Novel approaches for the treatment of methicillin-resistant Staphylococcus aureus: Using nanoparticles to overcome multidrug resistance

Methicillin-resistant Staphylococcus aureus (MRSA) causes serious infections in both community and hospital settings, with high mortality rates. Treatment of MRSA infections is challenging because of the rapidly evolving resistance mechanisms combined with the protective biofilms of S. aureus. Together, these characteristic resistance mechanisms continue to render conventional treatment modalities ineffective. The use of nanoformulations with unique modes of transport across bacterial membranes could be a useful strategy for disease-specific delivery. In this review, we summarize treatment approaches for MRSA, including novel techniques in nanoparticulate designing for better therapeutic outcomes; and facilitate an understanding that nanoparticulate delivery systems could be a robust approach in the successful treatment of MRSA.

Peptidoglycan-Binding Protein Metamaterials Mediated Enhanced and Selective Capturing of Gram-Positive Bacteria and Their Specific, Ultra-Sensitive, and Reproducible Detection via Surface-Enhanced Raman Scattering

Biological metamaterials with a specific size and spacing are necessary for developing highly sensitive and selective sensing systems to detect hazardous bacteria in complex solutions. Herein, the construction of peptidoglycan-binding protein (PGBP)-based metamaterials to selectively capture Gram-positive cells with high efficacy is reported. Nanoimprint lithography was used to generate a nanohole pattern as a template, the inside of which was modified with nickel(II)-nitrilotriacetic acid (Ni-NTA). Then, PGBP metamaterials were fabricated by immobilizing PGBP via chelation between Ni-NTA and six histidines on PGBP. Compared to the flat and spread PGBP-covered bare substrates, the PGBP-based metamaterials enabled selective capturing of Gram-positive bacteria with high efficacy, owing to enhanced interactions between the metamaterials and bacterial surface not shown in bulk materials. Thereafter, the specific strain and quantitative information of the captured bacteria was obtained by surface-enhanced Raman scattering mapping analysis in the 1 to 1 × 10⁶ cfu/mL range within 30 min. It should be noted that no additional signal amplification process was required for lowly abundant bacteria, even at the single-bacterium level. The PGBP-based metamaterials could be regenerated multiple times with preserved sensing efficiency. Finally, this assay can detect specific Gram-positive bacteria, such as Staphylococcus aureus, in human plasma.