Treatment Of Bacterial Infections Research Articles

Antibacterial efficacy and membrane mechanism of action of the Serratia-derived non-ionic lipopeptide, serrawettin W2-FL10.

Antimicrobial resistance is a major public health concern, urgently requiring antibacterial compounds exhibiting low adverse health effects. In this study, a novel antibacterial lipopeptide analog is described, serrawettin W2-FL10 (derived from Serratia marcescens), with potent activity displayed against Staphylococcus aureus. Mechanistic studies revealed that W2-FL10 targets the cell membrane of S. aureus, causing depolarization and permeabilization because of transmembrane lesions/pores, resulting in the leakage of intracellular components, possible cytosolic uptake of W2-FL10, and ultimately cell death. This study provides the first insight into the mode of action of a non-ionic lipopeptide. The low to moderate cytotoxicity of W2-FL10 also highlights its application as a promising therapeutic agent for the treatment of bacterial infections.

Ta4C3 Nanosheets as a Novel Therapeutic Platform for Photothermal-Driven ROS Scavenging and Immune Activation against Antibiotic-Resistant Infections in Diabetic Wounds.

The accumulation of excessive reactive oxygen species (ROS) and recurrent infections with drug-resistant bacteria pose significant challenges in diabetic wound infections, often leading to impediments in wound healing. Addressing this, there is a critical demand for novel strategies dedicated to treating and preventing diabetic wounds infected with drug-resistant bacteria. Herein, 2D tantalum carbide nanosheets (Ta4C3 NSs) have been synthesized through an efficient and straightforward approach, leading to the development of a new, effective nanoplatform endowed with notable photothermal properties, biosafety, and diverse ROS scavenging capabilities, alongside immunogenic attributes for diabetic wound treatment and prevention of recurrent drug-resistant bacterial infections. The Ta4C3 NSs exhibit remarkable photothermal performance, effectively eliminating methicillin-resistant Staphylococcus aureus (MRSA) and excessive ROS, thus promoting diabetic wound healing. Furthermore, Ta4C3 NSs enhance dendritic cell activation, further triggering T helper 1 (TH1)/TH2 immune responses, leading to pathogen-specific immune memory against recurrent MRSA infections. This nanoplatform, with its significant photothermal and immunomodulatory effects, holds vast potential in the treatment and prevention of drug-resistant bacterial infections in diabetic wounds.

Clinically important pharmacokinetic drug-drug interactions with antibacterial agents.

Antimicrobial agents are widely used, and drug interactions are challenging due to increased risk of adverse effects or reduced efficacy. Among the interactions, the most important are those affecting metabolism, although those involving drug transporters are becoming increasingly known. To make clinical decisions, it is key to know the intensity of the interaction, as well as its duration and time-dependent recovery after discontinuation of the causative agents. It is not only important to be aware of all patient treatments, but also of supplements and natural medications that may also interact. Although they can have serious consequences, most interactions can be adequately managed with a good understanding of them. Especially in patients with polipharmacy it is compulsory to check them with an electronic clinical decision support database. This article aims to conduct a narrative review focusing on the major clinically significant pharmacokinetic drug-drug interactions that can be seen in patients receiving treatment for bacterial infections.

Effect of Essential oil and Extracts of Artemisia Herba – Alba Plant Against Some E Pathogenic Bacteria

Artemisia Herba – Alba is the one of the most important genus of Asteraceae family. It has numerous values because of medicine properties. Artemisia Herba – Alba has numerous application in traditional medicine from ancient times. In this research, antimicrobial effects of leaf aqueous, alcoholic extracts and essential oil of Artemisia Herba – Alba against Staphylococcus aureus PTCC 1431 and Escherichia coli PTCC 1399 were studied, using agar disc diffusion method. Methanol and ethanol extracts obtained from leaves of A. Herba – Alba exhibited antimicrobial activity against test microorganisms. In addition Artemisia herba-alba essential oil was inhibitory effects against all studied pathogenic bacteria. The results showed that essential oil of Artemisia herba-alba had the most inhibition diameter zone in Staphylococcus aureusthan E.coli (25-17mm successively). Therefore in this research we showed that the positive gram bacteria are more sensitive than negative gram bacteria. our results indicate the possibility of using essential oil in the treatment of bacterial infections, and the results of this study was encouraging, despite the need for clinical studies to determine of the real effectiveness and potential toxic effects in vivo

Revolutionizing Nitrofurantoin Delivery: Unraveling Challenges and Pioneering Solutions for Enhanced Efficacy in UTI Treatment

Abstract: Nitrofurantoin is an antimicrobial drug, highly effective in the treatment of critical or chronic bacterial infections of the urinary tract, and hence, it is the first line choice of drug for the treatment of urinary tract infections (UTI). Although the molecule is legacy in nature, there are many challenges in terms of drug product formulation and efficacy thereof. The authors are main-ly focused in this literature review on, but not limited to, understanding the molecule in terms of physico-chemical properties of the drug, pharmacokinetics and pharmacodynamics, approved and withdrawn formulations, challenges concerning drug formulation, the cause of drug shortage in the market, improvement areas in terms of formulation and its therapeutic effectiveness. The au-thors found during their widespread review that the major challenge in the existing conventional drug delivery system of nitrofurantoin is the fluctuation of plasma concentration owing to its var-iability in drug absorption. Further, they understood that the variability in absorption is due to in-herent variability in particle size distribution. Based on the findings, authors also explored the possibilities to deliver the drug in novel drug delivery systems such as nano self-emulsifying emulsions, nanoemulsions and multiple emulsions where the drug can be presented in soluble form and hence the variability in absorption and fluctuation in plasma concentration of drug can be avoided and described briefly the salient features of each drug delivery in this review.

Bioinformatics analysis of clinical isolates of Escherichia coli from Nigeria and other countries for quinolone and fluoroquinolone resistance

Quinolones were the drugs of choice for the treatment of bacterial infections, especially, infections caused by Gram negative bacteria. Unfortunately, these drugs have been resisted by the microbial agents including Escherichia coli, known to be the leading cause of Urinary Tract Infection (UTI) globally. This study therefore was aimed at detecting all the genes involved in Quinolone resistance by the E. coli pathogen isolated from Nigeria and from other geographical regions, using robust techniques. Twenty-three sequence data files of Escherichia coli from various countries of the world were retrieved from the National Centre for biotechnology Information (NCBI) database and sent for genome assembly for processing of the short reads into long reads. The outcome was config. fasta files which were comprehensively annotated and characterized for genetic functions and mechanisms. A total of 208 antibiotic resistance genes were detected, out of which 27(13.0%) were linked to quinolone resistance and 14(6.7%) to multi- drug resistance. The result of this study significantly implicated many genes in quinolone resistance; notably were the efflux pump genes and their high percentage abundance. We recommend in-depth study of the genes for their expression capabilities, also the structure and features of the efflux pump genes to enable proper redesigning of drugs by integrating anti efflux pump substances that will selectively prevent the expression of the genes for antibiotic resistance, without any harm to the host, or that can destabilize the positive regulation of the operon for antibiotic resistance.

Eradication of Klebsiella pneumoniae pulmonary infection by silver oxytetracycline nano-structure

Targeted bactericidal nanosystems hold significant promise to improve the efficacy of existing antimicrobials for treatment of severe bacterial infections by minimizing the side effects and lowering the risk of antibiotic resistance development. In this work, Silver Oxytetracycline Nano-structure (Ag-OTC-Ns) was developed for selective and effective eradication of Klebsiella pneumoniae pulmonary infection. Ag-OTC-Ns were prepared by simple homogenization-ultrasonication method and were characterized by DLS, Zeta potential, TEM and FT-IR. The antimicrobial activity of Ag-OTC-Ns was evaluated in vitro using broth micro-dilution technique and time-kill methods. Our study showed that MICs of AgNO3, OTC, AgNPs and Ag-OTC-Ns were 100, 100, 50 and 6.25 µg/ml, respectively. Ag-OTC-Ns demonstrated higher bactericidal efficacy against the targeted Klebsiella pneumoniae at 12.5 µg/ml compared to the free Oxytetracycline, AgNO3 and AgNPs. In vivo results confirmed that, Ag-OTC-Ns could significantly eradicate K. pneumoniae from mice lung in compare with free Oxytetracycline, AgNO3 and AgNPs. In addition, Ag-OTC-Ns could effectually diminish the inflammatory biomarkers levels of Interferon Gamma and IL-12, and as a result it could effectively lower lung damage in K. pneumoniae infected mice. Ag-OTC-Ns has no significant toxicity on tested mice along the experimental period, there was no sign of behavioral abnormality in the surviving mice indicating that the Ag-OTC-Ns is safe at the used concentration. Furthermore, capability of 5 kGy Gamma ray to sterilize Ag-OTC-Ns solution without affecting it stability was proven.

Understanding and Application of Antibiotics: Analysis among Students of Health Science in Sarajevo with an Emphasis on Gender Distribution

Antibiotics are medications that inhibit bacterial growth and are used in the treatment of bacterial infections, both gram-positive and gram-negative. Antibiotics also represent products of metabolism of certain microorganisms that adversely affect the development and reproduction of other microorganisms. They are one of the greatest discoveries of modern medicine; however, in today's age, the greatest challenge is the resistance of bacteria to antibiotics. There are numerous reasons for the emergence of antibiotic resistance. One reason lies in inadequate education about antibiotics, their application, and usage. The aim of this study was to survey students of the University of Sarajevo's Faculty of Health Sciences about their general knowledge of antibiotics and their methods of application. A total of 151 students participated in this study, including 125 females (83%) and 26 males (17%). The questions consisted of two parts: the first part covered general knowledge about antibiotics, while the second part addressed bacterial resistance to antibiotics.

Bacteriophage-resistant carbapenem-resistant Klebsiella pneumoniae shows reduced antibiotic resistance and virulence

Phage therapy has shown great promise in the treatment of bacterial infections. However, the effectiveness of phage therapy is compromised by the inevitable emergence of phage-resistant strains. In this study, a phage-resistant carbapenem-resistant Klebsiella pneumoniae strain SWKP1711R, derived from parental carbapenem-resistant K. pneumoniae strain SWKP1711 was identified. The mechanism of bacteriophage resistance in SWKP1711R was investigated and the molecular determinants causing altered growth characteristics, antibiotic resistance, and virulence of SWKP1711R were tested. Compared to SWKP1711, SWKP1711R showed slower growth, smaller colonies, filamentous cells visible under the microscope, reduced production of capsular polysaccharide (CPS) and lipopolysaccharide, and reduced resistance to various antibiotics accompanied by reduced virulence. Adsorption experiments showed that phage vB_kpnM_17-11 lost the ability to adsorb onto SWKP1711R, and the adsorption receptor was identified to be bacterial surface polysaccharides. Genetic variation analysis revealed that, compared to the parental strain, SWKP1711R had only one thymine deletion at position 78 of the open reading frame of the lpcA gene, resulting in a frameshift mutation that caused alteration of the bacterial surface polysaccharide and inhibition of phage adsorption, ultimately leading to phage resistance. Transcriptome analysis and quantitative reverse transcriptase PCR revealed that genes encoding lipopolysaccharide synthesis, ompK35, blaTEM-1, and type II and Hha-TomB toxin-antitoxin systems, were all downregulated in SWKP1711R. Taken together, the evidence presented here indicates that the phenotypic alterations and phage resistance displayed by the mutant may be related to the frameshift mutation of lpcA and altered gene expression. While evolution of phage resistance remains an issue, our study suggests that the reduced antibiotic resistance and virulence of phage-resistant strain derivatives might be beneficial in alleviating the burden caused by multidrug-resistant bacteria.

Influence of antibiotics on the development of mitochondrial dysfunction.

Antibiotics are an indispensable component of therapeutic strategies in the treatment of severe bacterial infections. Unfortunately, in addition to the emerging resistance of bacteria to antibiotics, side effects are an important problem with their use. Knowledge of the mechanisms underlying the development of side effects can make it possible to understand how it is possible to reduce their negative impact on the health of patients. One of the negative effects of antibiotics on the human organism is interference with homeostasis and the functioning of mitochondria. Side effects of antibiotics based on this influence require further study. Here we consider the mitochondria as a side target of antibiotics and the main strategies of antibiotics that cause mitochondrial dysfunction. Options are also considered on how to deal with this problem and even use it for good.

Exploration of morpholine-thiophene hybrid thiosemicarbazones for the treatment of ureolytic bacterial infections via targeting urease enzyme: Synthesis, biochemical screening and computational analysis

An important component of the pathogenicity of potentially pathogenic bacteria in humans is the urease enzyme. In order to avoid the detrimental impact of ureolytic bacterial infections, the inhibition of urease enzyme appears to be an appealing approach. Therefore, in the current study, morpholine-thiophene hybrid thiosemicarbazone derivatives (5a-i) were designed, synthesized and characterized through FTIR, 1H NMR, 13C NMR spectroscopy and mass spectrometry. A range of substituents including electron-rich, electron-deficient and inductively electron-withdrawing groups on the thiophene ring was successfully tolerated. The synthesized derivatives were evaluated in vitro for their potential to inhibit urease enzyme using the indophenol method. The majority of compounds were noticeably more potent than the conventional inhibitor, thiourea. The lead inhibitor, 2-(1-(5-chlorothiophen-2-yl)ethylidene)-N-(2-morpholinoethyl)hydrazinecarbothioamide (5g) inhibited the urease in an uncompetitive manner with an IC50 value of 3.80 ± 1.9 µM. The findings of the docking studies demonstrated that compound 5g has a strong affinity for the urease active site. Significant docking scores and efficient binding free energies were displayed by the lead inhibitor. Finally, the ADME properties of lead inhibitor (5g) suggested the druglikeness behavior with zero violation.

Construction of self‐healing gallium (III)‐cross‐linked konjac glucomannan/polyacrylamide hydrogels for efficiently killing bacteria and accelerating wound healing

AbstractGallium ions have a special action mechanism that interferes bacterial iron metabolism, thereby possessing great potential for the treatment of bacterial infections. In this work, gallium ions‐cross‐linked konjac glucomannan/polyacrylamide (KGM/PAM/Ga3+) hydrogels are successfully constructed with satisfactory swelling ability, appropriate mechanical properties and adjustable degradation performance. Ga ions as a kind of cross‐linking agent can enhance the stability, and more importantly, improve the bactericidal ability of hydrogel, thus forming novel functional KGM/PAM/Ga3+ hydrogels for treating wounds. After the evaluation of antibacterial activity and biocompatibility, KGM/PAM/Ga3+ hydrogels can effectively inhibit the proliferation of bacteria through the gradual and sustainable release of Ga ions from the hydrogel with negligible cytotoxicity and good blood compatibility. Furthermore, they possess exceptional self‐healing behavior, and can be readily adapted to varying degrees of bending, which matches skin wound dressing application. Finally, the results of wound healing performance and histological evaluation demonstrate that KGM/PAM/Ga3+ hydrogels can efficiently accelerate infected wound healing and facilitate the regeneration of skin tissues.

Multidrug-resistant Staphylococcus chromogenes pyoderma in Rattus norvegicus: case report

This case study investigated a multidrug-resistant Staphylococcus pyoderma infection in a pet Rattus norvegicus. The clinical presentation involved a range of clinical signs, including pruritus, inflammation, pustules, and crusts on the skin, indicative of bacterial pyoderma. Conventional and molecular techniques were used, and the pathogen was identified as Staphylococcus chromogenes. The suspected transmission route was through a bite from another rat, although the aggressor was not tested. Initial treatment with enrofloxacin proved ineffective. Subsequently, an amoxicillin + potassium clavulanate treatment resulted in temporary improvement. Nevertheless, the infection relapsed after 30 days, necessitating a repeated course of treatment. The findings underscore the importance of accurate diagnosis, appropriate testing, and adherence to prescribed treatments for bacterial infections. The zoonotic potential of multidrug-resistant Staphylococcus highlights the need for better education of pet owners on transmission risks and treatment compliance. Additional research is essential to explore the transmission routes of this infection, the potential risks to pet owners, and to gain a more comprehensive understanding of Staphylococcus chromogenes pyoderma in domestic rodents.

Deferoxamine-Loaded Injectable Chitosan-Grafted Chlorogenic Acid/Oxidized Hyaluronic Acid Hybrid Hydrogel with Antibacterial, Anti-inflammatory, and Angiogenesis-Promoting Properties for Diabetic Wound Repair.

Diabetic chronic wounds are notoriously difficult to heal as a result of their susceptibility to infection. To address this issue, we constructed an innovated and adaptable solution in the form of injectable chitosan (CS) hydrogel, denoted as CCOD, with enhanced antibacterial and anti-inflammatory properties. This hydrogel is created through a Schiff base reaction that combines chitosan-grafted chlorogenic acid (CS-CGA) and oxidized hyaluronic acid (OHA) with deferoxamine (DFO) as a model drug. The combination of CS and CGA has demonstrated excellent antibacterial and anti-inflammatory properties, while grafting played a pivotal role in making these positive effects stable. These unique features make it possible to customize injectable hydrogel and fit any wound shape, allowing for more effective and personalized treatment of complex bacterial infections. Furthermore, the hydrogel system is not only effective against inflammation and bacterial infections but also possesses antioxidant and angiogenic abilities, making it an ideal solution for the repair of chronic wounds that have been previously thought of as unmanageable.

Acquired Bartter-like syndrome associated with colistin use in an adult patient: a case report.

Colistin is an effective antibiotic utilized for the treatment of Gram-negative bacterial infections with coverage against a broad spectrum of bacteria. Despite the broad antibacterial coverage, this antibiotic can have serious complications such as acute kidney injury. Colistin also can have a toxic effect on the loop of Henle, causing tubulopathy, electrolyte imbalances, and the occurrence of Bartter-like syndrome (BLS) which is characterized by magnesium and calcium disturbances, polyuria, and metabolic alkalosis. We here report a 32-year-old male with a history of multiple trauma due to an accident that received colistin therapy for Pseudomonas isolation from wound culture on the 5th day of hospitalization. Polyuria, hypokalemic metabolic alkalosis, hypomagnesemia, and hypocalcemia were developed on the first week of colistin administration. The patient received colistin until the 21st day of hospitalization. Serum calcium and magnesium levels became normal 1 day after stopping colistin, while urine volume and metabolic alkalosis resolved 6 days after colistin discontinuing. Therefore, it is crucial to adjust the dose of colistin to minimize its toxicity.

Low-friction soft robots for targeted bacterial infection treatment in gastrointestinal tract

Low-friction soft robots for targeted bacterial infection treatment in gastrointestinal tract

Design and discovery of urease and Helicobacter pylori inhibitors based on benzofuran/benzothiophene-sulfonate and sulfamate scaffolds for the treatment of ureolytic bacterial infections

A series of sulfonate and sulfamate derivatives bearing benzofuran or benzothiophene scaffold exhibited potent inhibitory effect on urease enzyme. Most of the derivatives exhibited significantly higher potency than thiourea, the standard inhibitor. Compound 1s was identified as the most potent urease inhibitor with an IC50 value of 0.42 ± 0.08 μM, which is 53-fold more potent than thiourea, positive control (IC50 = 22.3 ± 0.031 μM). The docking results further revealed the binding interactions towards the urease active site. Phenotypic screening revealed that compounds 1c, 1d, 1e, 1f, 1j, 1n, and 1t exhibit high potency against H. pylori with MIC values ranging from 0.00625 to 0.05 mM and IC50 values ranging from 0.0031 to 0.0095 mM, much more potent than the positive control, acetohydroxamic acid (MIC and IC50 values were 12.5 and 7.38 mM, respectively). Additional studies were performed to investigate the toxicity of these compounds against the gastric epithelial cell line (AGS) and their selectivity profile against E. coli, and five Lactobacillus species representative of the gut microflora. Permeability characteristics of the most promising derivatives were investigated in Caco-2 cell line. The results indicate that the compounds could be targeted in the GIT only without systemic side effects.

Brucine Sulfate, a Novel Bacteriostatic Agent in 3D Printed Bone Scaffold Systems.

Bacterial infection is a common complication in bone defect surgery, in which infection by clinically resistant bacteria has been a challenge for the medical community. Given this emerging problem, the discovery of novel natural-type inhibitors of drug-resistant bacteria has become imperative. Brucine, present in the traditional Chinese herb Strychnine semen, is reported to exert analgesic and anti-inflammatory effects. Brucine's clinical application was limited because of its water solubility. We extracted high-purity BS by employing reflux extraction and crystallization, greatly improved its solubility, and evaluated its antimicrobial activity against E. coli and S. aureus. Importantly, we found that BS inhibited the drug-resistant strains significantly better than standard strains and achieved sterilization by disrupting the bacterial cell wall. Considering the safety concerns associated with the narrow therapeutic window of BS, a 3D BS-PLLA/PGA bone scaffold system was constructed with SLS technology and tested for its performance, bacteriostatic behaviors, and biocompatibility. The results have shown that the drug-loaded bone scaffolds had not only long-term, slow-controlled release with good cytocompatibility but also demonstrated significant antimicrobial activity in antimicrobial testing. The above results indicated that BS may be a potential drug candidate for the treatment of antibiotic-resistant bacterial infections and that scaffolds with enhanced antibacterial activity and mechanical properties may have potential applications in bone tissue engineering.

Novel biaryloxazolidinone derivatives with broad-spectrum antibacterial activity, favorable drug-like profiles and in vivo efficacy against linezolid-resistant Staphylococcusaureus

The emergence of multidrug-resistant bacteria along with a declining pipeline of clinically useful antibiotics has led to the urgent need for the development of more effective antibacterial agents to treat drug-resistant bacteria. We previously discovered compound OB-158 with potent antibacterial activity but exhibited poor oral bioavailability. Herein, a systematic structural optimization of OB-158 to improve pharmacokinetic profiles yielded 26 novel biaryloxazolidinone analogues, and their activities against Gram-positive S. aureus, multidrug resistant S. aureus and Enterococcus faecalis were evaluated. Remarkably, compound 8b was identified with potent antibacterial activity against S. aureus (MIC=0.06μg/mL), MSSA (MIC=0.125μg/mL), MRSA (MIC=0.06μg/mL), LRSA (MIC=0.125μg/mL) and LREFa (MIC=0.5μg/mL). Compound 8b was demonstrated as a promising candidate through druglikeness evaluation including metabolism in microsomes and plasma, Caco-2cell permeability, plasma protein binding, cytotoxicity, and inhibition of CYP450 and human monoamine oxidase. Notably, compound 8b displayed excellent PK profile with appropriate T1/2 of 1.49h, high peak plasma concentration (Cmax=2320ng/mL), high plasma exposure (AUC0-t=8310hng/mL), and superior oral bioavailability (F=68.1%) in Sprague-Dawley rats. Ultimately, in vivo efficacy of compound 8b in a mouse model of LRSA systemic infection was also demonstrated. Taken together, compound 8b represents a promising drug candidate for the treatment of linezolid-resistant Gram-positive bacterial strains infection.

PREVENTION OF INTESTINAL INFECTIONS OF BACTERIAL ETIOLOGY IN PIGS

Intestinal infections of bacterial etiology are among the most common diseases in pigs of different age groups. Healthy gastrointestinal tract is the basis for successful pig farming. Therefore, the prevention and control of major gastrointestinal infections is a key to farm profitability. Intestinal infections are caused by both pathogenic and opportunistic pathogenic bacteria. The most common diseases caused by pathogenic microorganisms include dysentery, ileitis and salmonellosis. Their causative agents are the bacteria Brachyspira spp., Lawsonia spp. and Salmonella spp. respectively. The most common opportunistic pathogenic bacteria are: Escherichia coli, Clostridium spp. and Proteus spp. Bacterial intestinal infections are diverse and widespread, and therefore cause significant economic losses for livestock farms. They suffer significant losses due to animal mortality, reduced productivity and, as a result, increased treatment costs. Therefore, the efforts of scientists should be aimed at creating innovative approaches and effective therapeutic agents that would not only treat but also prevent bacterial intestinal infections. The article presents data on traditional and innovative approaches to the prevention of bacterial intestinal infections in pigs. The advantages of using feed additives for the prevention and treatment of bacterial intestinal infections in pigs are described.