A ruthenium nanoframe/enzyme composite system as a self-activating cascade agent for the treatment of bacterial infections

Nanoscale ◽  
2021 ◽  
Author(s):  
Yanan Liu ◽  
Dongliang Huo ◽  
Xufeng Zhu ◽  
Xu Chen ◽  
Ange Lin ◽  
...  
Keyword(s):  
Antibacterial Activity ◽  
Bacterial Infection ◽  
Hydroxyl Radicals ◽  
Bacterial Infections ◽  
Composite System ◽  
Cascade Agent

The cascade catalytic strategy could effectively enhance the antibacterial activity by regulating the production of hydroxyl radicals (˙OH) in the sites of bacterial infection.

Procalcitonin Testingreduce Unnecessary Antibiotic Use in Bacterial Infection

2019 ◽  
Vol 2 (1) ◽  
pp. 1-3
Author(s):  
Attabak Toofani Milani ◽  
Mahshid Mohammadian ◽  
Sadegh Rostaminasab ◽  
Roghayeh Paribananaem ◽  
Zohre Ahmadi ◽  
...  
Keyword(s):  
Antibiotic Therapy ◽  
Bacterial Infection ◽  
Diagnostic Test ◽  
Bacterial Infections ◽  
Intervention Studies ◽  
Antibiotic Use ◽  
Clinical Suspicion ◽  
Diagnostic Biomarker ◽  
Clinical Routine ◽  
Initial Rise

Conventional diagnostic test have limitations to deferential diagnosis in clinical suspicion ofbacterial infection cases, that in some cases lead to inappropriate antibiotic therapy and increases antibiotic resistance. A new diagnostic insight is procalcitonin (PCT) test to improve diagnosis of bacterial infections and to guide antibiotic therapy. Serum PCT levels are of useful test as a biomarker in patients with bacterial infections for several reasons. Initial rise of PCT levels due to bacterial infection, subsequent sequential PCT levels can be used to assess the effectiveness and duration of antibiotic therapy. Based on clinical researches results, in bacterial infections, promising good results obtained when use of PCT used as differential diagnostic test. But further intervention studies are needed before use of PCT in clinical routine tests. The goal of this review is to study the PCT reliability as infections diagnostic biomarker.

Fluoroquinolone-3-carboxamide Amino Acid Conjugates: Synthesis, Antibacterial Properties And Molecular Modeling Studies

2020 ◽  
Vol 17 (1) ◽  
pp. 71-84
Author(s):  
Riham M. Bokhtia ◽  
Siva S. Panda ◽  
Adel S. Girgis ◽  
Hitesh H. Honkanadavar ◽  
Tarek S. Ibrahim ◽  
...  
Keyword(s):  
Experimental Data ◽  
Antibacterial Activity ◽  
Amino Acid ◽  
Bacterial Infections ◽  
Antibacterial Agents ◽  
Antibacterial Properties ◽  
Computational Studies ◽  
Protecting Group ◽  
Amino Acid Conjugates ◽  
Molecular Modeling Studies

Background: Bacterial infections are considered as one of the major global health threats, so it is very essential to design and develop new antibacterial agents to overcome the drawbacks of existing antibacterial agents. Method: The aim of this work is to synthesize a series of new fluoroquinolone-3-carboxamide amino acid conjugates by molecular hybridization. We utilized benzotriazole chemistry to synthesize the desired hybrid conjugates. Result: All the conjugates were synthesized in good yields, characterized, evaluated for their antibacterial activity. The compounds were screened for their antibacterial activity using methods adapted from the Clinical and Laboratory Standards Institute. Synthesized conjugates were tested for activity against medically relevant pathogens; Escherichia coli (ATCC 25922), Pseudomonas aeruginosa (ATCC 27856) Staphylococcus aureus (ATCC 25923) and Enterococcus faecalis (ATCC 19433). Conclusion: The observed antibacterial experimental data indicates the selectivity of our synthesized conjugates against E.Coli. The protecting group on amino acids decreases the antibacterial activity. The synthesized conjugates are non-toxic to the normal cell lines. The experimental data were supported by computational studies.

Crystalline ruthenium polypyridyl nanoparticles: a targeted treatment of bacterial infection with multifunctional antibacterial, adhesion and surface-anchoring photosensitizer properties

2021 ◽  
Author(s):  
Chenyang Yin ◽  
Zekun Wang ◽  
Xiaoyuan Ding ◽  
Xiaoqing Chen ◽  
Jingyuan Wang ◽  
...  
Keyword(s):  
Bacterial Infection ◽  
Antibacterial Therapy ◽  
Bacterial Infections ◽  
Targeted Treatment ◽  
Ruthenium Polypyridyl ◽  
Surface Anchoring ◽  
Antibacterial Materials

Photodynamic antibacterial therapy employs nanocomposites as an alternative to traditional antibiotics for the treatment of bacterial infections. However, many of these antibacterial materials are less effective towards bacteria than traditional...

Bacterial Infection and Splenic Reticuloendothelial Function in Children with Hemoglobin SC Disease

PEDIATRICS ◽  
1983 ◽  
Vol 72 (1) ◽  
pp. 93-98
Author(s):  
George R. Buchanan ◽  
Susan J. Smith ◽  
Christine A. Holtkamp ◽  
John P. Fuseler
Keyword(s):  
Bacterial Infection ◽  
Bacterial Infections ◽  
Infection Risk ◽  
Bacterial Disease ◽  
Normal Children ◽  
Splenic Function ◽  
Focus Of Infection ◽  
Serious Bacterial Infections ◽  
Primary Focus ◽  
Hemoglobin Sc Disease

Although the epidemiology and pathophysiology of serious bacterial infection in homozygous sickle cell anemia (SS disease) have become increasingly well understood, information about infection risk and splenic reticuloendothelial function in hemoglobin SC disease is quite limited. Therefore, the type and frequency of invasive bacterial disease were examined in 51 children with SC disease followed for 370 person-years and splenic function was assessed in 31 patients by quantitation of pitted erythrocytes. Seven serious bacterial infections occurred in four of the patients, five due to Streptococcus pneumoniae and two to Haemophilus influenzae. A primary focus of infection was present in all episodes, none of which proved fatal. Although 30 episodes of pneumonia or chest syndrome occurred in 20 of the patients, a bacterial etiology was proven in only three instances. Splenic function was usually impaired, with a mean pit count of 7.1% ± 8.2% (range 0% to 22.9%). This is significantly greater than normal, but less than pit counts in patients with SS disease or asplenic subjects. Children with SC disease may have a greater risk of bacterial infection than normal children, but their infection rate is not nearly as high as that in patients with SS disease.

Atypical Bacterial Infections Explained by a Concomitant Virus Infection

PEDIATRICS ◽  
1985 ◽  
Vol 76 (3) ◽  
pp. 411-414
Author(s):  
Ron Dagan ◽  
Caroline B. Hall ◽  
Marilyn A. Menegus
Keyword(s):  
Early Childhood ◽  
Virus Infection ◽  
Bacterial Infection ◽  
Clinical Manifestation ◽  
Bacterial Infections ◽  
Recent Progress ◽  
Clinical Presentation ◽  
Virus Detection ◽  
Dual Infection ◽  
Dual Infections

Because both viral and bacterial infections are common during early childhood, dual infections are not unexpected. However, the clinical manifestation of such combined infections may be, difficult to interpret, and they are often misdiagnosed as "atypical bacterial infection." Five patients with concomitant viral-bacterial infections are described. In all five cases, virus detection enabled the physicians to better understand an otherwise puzzling clinical presentation. In view of the recent progress in rapid viral diagnoses and the potential of antiviral drugs, the possibility of dual infection should be investigated more often.

scholarly journals Implementation of a Pragmatic Biomarker-Driven Algorithm to Guide Antibiotic Use in the Pediatric Intensive Care Unit: the Optimizing Antibiotic Strategies in Sepsis (OASIS) II Study

2018 ◽  
Vol 9 (1) ◽  
pp. 36-43 ◽  
Author(s):  
Kevin J Downes ◽  
Julie C Fitzgerald ◽  
Emily Schriver ◽  
Craig L K Boge ◽  
Michael E Russo ◽  
...  
Keyword(s):  
Intensive Care Unit ◽  
Intensive Care ◽  
Bacterial Infection ◽  
Pediatric Intensive Care Unit ◽  
Bacterial Infections ◽  
Pediatric Intensive Care ◽  
Antibiotic Use ◽  
Antibiotic Administration ◽  
Period 2 ◽  
Rate Ratios

Abstract Background Biomarkers can facilitate safe antibiotic discontinuation in critically ill patients without bacterial infection. Methods We tested the ability of a biomarker-based algorithm to reduce excess antibiotic administration in patients with systemic inflammatory response syndrome (SIRS) without bacterial infections (uninfected) in our pediatric intensive care unit (PICU). The algorithm suggested that PICU clinicians stop antibiotics if (1) C-reactive protein <4 mg/dL and procalcitonin <1 ng/mL at SIRS onset and (2) no evidence of bacterial infection by exam/testing by 48 hours. We evaluated excess broad-spectrum antibiotic use, defined as administration on days 3–9 after SIRS onset in uninfected children. Incidence rate ratios (IRRs) compared unadjusted excess length of therapy (LOT) in the 34 months before (Period 1) and 12 months after (Period 2) implementation of this algorithm, stratified by biomarker values. Segmented linear regression evaluated excess LOT among all uninfected episodes over time and between the periods. Results We identified 457 eligible SIRS episodes without bacterial infection, 333 in Period 1 and 124 in Period 2. When both biomarkers were below the algorithm’s cut-points (n = 48 Period 1, n = 31 Period 2), unadjusted excess LOT was lower in Period 2 (IRR, 0.53; 95% confidence interval, 0.30–0.93). Among all 457 uninfected episodes, there were no significant differences in LOT (coefficient 0.9, P = .99) between the periods on segmented regression. Conclusions Implementation of a biomarker-based algorithm did not decrease overall antibiotic exposure among all uninfected patients in our PICU, although exposures were reduced in the subset of SIRS episodes where biomarkers were low.

scholarly journals EVALUATION OF ANTIOXIDANT AND ANTIBACTERIAL ACTIVITY OF GLYCYRRHIZA GLABRA ROOT EXTRACTS

2020 ◽  
pp. 166-170
Author(s):  
SHUSHIL BHUSAL ◽  
KHAGA RAJ SHARMA
Keyword(s):  
Antibacterial Activity ◽  
Bacillus Subtilis ◽  
Bacterial Infections ◽  
Plant Secondary Metabolites ◽  
Glycyrrhiza Glabra ◽  
Antioxidant Potential ◽  
Diffusion Method ◽  
Phytochemical Analysis ◽  
Meoh Extract ◽  
Etoac Fraction

Objectives: The present study was designed to investigate the phytochemical analysis, antioxidant potential, and antibacterial activities of the traditionally used medicinal plant Glycyrrhiza glabra. Methods: The plant secondary metabolites were extracted through cold percolation using methanol (MeOH) as a solvent. The MeOH extract was further fractionated in different solvents in increasing order of polarity. The antioxidant activity was evaluated by 2,2-diphenyl-1-picrylhydrazyl assay. The antibacterial activity was studied by agar well diffusion method. Results: The antioxidant potential IC50 was found 43.13, 104.83, and 200.11 μg/ml for ethyl acetate (EtOAc), MeOH, and chloroform (CHCl3) extracts, respectively. The EtOAc fraction showed the potent antioxidant with IC50 43.13 μg/ml compared to the standard ascorbic acid 58.76 μg/ml. The antimicrobial activity exhibited by MeOH extract against Bacillus subtilis (ATCC 6051) and Staphylococcus aureus (ATCC 6538P) zone of inhibition was 18 mm and 17 mm, for chloroform extracts 15 mm and 13 mm, and for EtOAc fraction 11 mm against Bacillus subtilis. The highest dilution that yielded no single bacteria colony on the nutrient agar plates for Bacillus subtilis and S. aureus of MeOH extract was found 0.39 mg/ml and 6.25 mg/ml, for chloroform extract 3.125 mg/ml and 6.25 mg/ml and EtOAc fraction against Bacillus subtilis was 12.50 mg/ml as minimum bactericidal concentration. Conclusion: The plant extracts showed potent antioxidant and antibacterial activity. The results support for using the G. glabra in bacterial infection which provides partial scientific validation for using the plant against bacterial infections.

scholarly journals Imaging Sensitive and Drug-Resistant Bacterial Infection with [11C]-TMP: In Vitro and First-in-Human Evaluation

2021 ◽  
Author(s):  
Iris K Lee ◽  
Daniel A Jacome ◽  
Joshua K Cho ◽  
Vincent Tu ◽  
Anthony Young ◽  
...  
Keyword(s):  
Bacterial Infection ◽  
Mammalian Cells ◽  
Bacterial Infections ◽  
The Body ◽  
Response Monitoring ◽  
Drug Resistant ◽  
Bacterial Strains ◽  
Critical Question ◽  
In Vitro Uptake

Recently, several molecular imaging strategies have developed to image bacterial infections in humans. Nuclear approaches, specifically positron emission tomography (PET), affords sensitive detection and the ability to non-invasively locate infections deep within the body. Two key radiotracer classes have arisen: metabolic approaches targeting bacterial specific biochemical transformations, and antibiotic-based approaches that have inherent selectivity for bacteria over mammalian cells. A critical question for clinical application of antibiotic radiotracers is whether resistance to the template antibiotic abrogates specific uptake, thus diminishing the predictive value of the diagnostic test. We recently developed small-molecule PET radiotracers based on the antibiotic trimethoprim (TMP), including [11C]-TMP, and have shown their selectivity for imaging bacteria in preclinical models. Here, we measure the in vitro uptake of [11C]-TMP in pathogenic susceptible and drug-resistant bacterial strains. Both resistant and susceptible bacteria showed similar in vitro uptake, which led us to perform whole genome sequencing of these isolates to identify the mechanisms of TMP resistance that permit retained radiotracer binding. By interrogating these isolate genomes and a broad panel of previously sequenced strains, we reveal mechanisms where uptake or binding of TMP radiotracers can potentially be maintained despite the annotation of genes conferring antimicrobial resistance. Finally, we present several examples of patients with both TMP-sensitive and drug-resistant infections in our first-in-human experience with [11C]-TMP. This work underscores the ability of an antibiotic radiotracer to image bacterial infection in patients, which may allow insights into human bacterial pathogenesis, infection diagnosis, and antimicrobial response monitoring.

scholarly journals Usefulness of procalcitonin (PCT), C-reactive protein (CRP), and white blood cell (WBC) levels in the differential diagnosis of acute bacterial, viral, and mycoplasmal respiratory tract infections in children

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Yang Li ◽  
Lanfang Min ◽  
Xin Zhang
Keyword(s):  
Differential Diagnosis ◽  
Respiratory Tract ◽  
Bacterial Infection ◽  
Bacterial Infections ◽  
Respiratory Tract Infections ◽  
Respiratory Infections ◽  
Diagnostic Value ◽  
Significant Difference ◽  
Group A ◽  
Tract Infections

Abstract Background There is a lack of studies comparing PCT, CRP and WBC levels in the differential diagnosis of acute bacterial, viral, and mycoplasmal respiratory tract infections. It is necessary to explore the correlation between above markers and different types of ARTI. Methods 108 children with confirmed bacterial infection were regarded as group A, 116 children with virus infection were regarded as group B, and 122 children with mycoplasmal infection were regarded as group C. The levels of PCT, CRP and WBC of the three groups were detected and compared. Results The levels of PCT, CRP and WBC in group A were significantly higher than those in groups B and C (p < 0.05). The positive rate of combined detection of PCT, CRP and WBC was significant higher than that of single detection. There was no significant difference in PCT, CRP and WBC levels between the group of G+ bacterial infection and G− bacterial infection (p > 0.05). ROC curve results showed that the AUC of PCT, CRP and WBC for the diagnosis of bacterial respiratory infections were 0.65, 0.55, and 0.58, respectively. Conclusions PCT, CRP and WBC can be combined as effective indicators for the identification of acute bacterial or no-bacterial infections in children. The levels of PCT and CRP have higher differential diagnostic value than that of WBC in infection, and the combined examination of the three is more valuable in clinic.

scholarly journals Roles of a Mast Cell–Specific Receptor MRGPRX2 in Host Defense and Inflammation

2020 ◽  
Vol 99 (8) ◽  
pp. 882-890 ◽  
Author(s):  
C. Chompunud Na Ayudhya ◽  
S. Roy ◽  
M. Thapaliya ◽  
H. Ali
Keyword(s):  
Mast Cells ◽  
Bacterial Infection ◽  
Host Defense ◽  
Immune Cells ◽  
Inflammatory Pain ◽  
Bacterial Infections ◽  
Neurogenic Inflammation ◽  
Inflammatory Diseases ◽  
Adaptive Immune Cells ◽  
Novel Approaches

Mast cells are multifunctional immune cells that are found most abundantly at host-environment interfaces, such as the skin, respiratory tract, and oral/gastrointestinal mucosa. Not surprisingly, mast cells act as sentinel cells that sense microbial attacks and initiate a protective immune response and promote healing. Although mast cells share many features with other innate immune effector cells, such as neutrophils and macrophages, they uniquely interact closely with blood vessels and release an extensive set of mediators for the recruitment of innate and adaptive immune cells. A novel human G protein-coupled receptor (GPCR), known as Mas-related GPCR-X2 (MRGPRX2, mouse ortholog, MrgprB2), has recently been identified, which is expressed on mast cells but not neutrophils and macrophages. Interestingly, activation of MrgprB2 by bacteria-derived quorum-sensing peptides inhibits bacterial growth, prevents biofilm formation, and leads to the recruitment of neutrophils to effectively clear bacteria. Furthermore, host defense antimicrobial peptides and small-molecule peptide mimetics also activate mast cells via MRGPRX2/B2. MrgprB2-mediated activation of local mast cells also clears cutaneous bacterial infection, promotes healing, and protects against reinfection. In addition to their role in host defense, mast cells contribute to a number of chronic inflammatory diseases such as periodontitis, neurogenic inflammation, and inflammatory pain likely via the activation of MRGPRX2. In this review, we discuss the roles of MRGPRX2/B2 in the clearance of bacterial infection, wound healing, periodontal disease, neurogenic inflammation, and inflammatory pain. We propose that harnessing mast cells’ host defense and immunomodulatory properties via the activation of MRGPRX2 may lead to novel approaches for the treatment of drug-resistant bacterial infections. On the other hand, increased MRGPRX2 expression on mast cells and their inappropriate activation may contribute to periodontitis, neurogenic inflammation, and inflammatory pain. Thus, targeting MRGPRX2 could provide novel approaches to modulate these conditions.

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