Increase In Antibiotic Resistance Research Articles

Gallium-based metal-organic frameworks loaded with antimicrobial peptides for synergistic killing of drug-resistant bacteria.

Increased antibiotic resistance has made bacterial infections a global concern, which requires novel non-antibiotic-dependent antibacterial strategies to address the menace. Antimicrobial peptides (AMPs) are a promising antibiotic alternative, whose antibacterial mechanism is mainly to destroy the membrane of bacteria. Gallium ions exhibit an antibacterial effect by interfering with the iron metabolism of bacteria. With the rapid development of nanotechnology, it is worth studying the potential of gallium-AMP-based nanocomposites for treating bacterial infections. Herein, novel gallium-based metal-organic frameworks (MOFs) were synthesized at room temperature, followed by in situ loading of the model AMP melittin. The obtained nanocomposites exhibited stronger antibacterial activity than pure MEL and gallium ions, achieving the effects of "one plus one is greater than two". Moreover, the nanocomposites showed favorable biocompatibility and accelerated healing of a wound infected by methicillin-resistant Staphylococcus aureus by down-regulation of inflammatory cytokines IL-6 and TNF-α. This work presents an innovative antibacterial strategy to overcome the antibiotic resistance crisis and expand the application of AMPs.

Potential application of menadione for antimicrobial coating of surgical sutures

Staphylococcal-associated surgical site infections (SSI) are common nosocomial infections in healthcare facilities worldwide. The use of antiseptic-coated sutures has been recommended to minimise the risk of SSI in clinical settings. However, as there has been a growing concern over antibiotic resistance resulting from antiseptic usage, development of antimicrobial sutures using alternative compounds is necessary. In this study, menadione (2-methyl-1,4-napthoquinone), also known as Vitamin K3, was evaluated as a potential antimicrobial compound for suture coating. The anti-staphylococcal activity of menadione was assessed using microbroth dilution method and biofilm inhibition assays. The low menadione minimum biofilm inhibitory concentration values against both methicillin-susceptible and -resistant S. aureus strains indicate its inhibitory activity against staphylococcal biofilm. Menadione-coated sutures were prepared by dip-coating surgical sutures in slurries containing poly(D,L-lactide-co-glycolide) polymers (either 65:35 or 75:25) and calcium stearate. Zone of inhibition assays showed dose-dependent antimicrobial effects of the sutures up to four days. A ∼3 log10 colony forming unit/ml reduction of adherent bacteria (p < 0.05) on the sutures was demonstrated via bacterial adherence assays. The integrity and tensile strength of the sutures were unaffected by the coating procedure. In view of the increased antibiotic resistance and limited antimicrobials, menadione may be potentially useful for antimicrobial coating of surgical sutures.

AdeB and adeG Over Expression Increase Antibiotic Resistance in Acinetobacter baumannii Clinical Isolates from Burns Infection Patients in Mosul City, Iraq

adeB and adeG Over Expression Increase Antibiotic Resistance in Acinetobacter baumannii Clinical Isolates from Burns Infection Patients in Mosul City, Iraq

Isolation of Lytic Bacteriophage against Some Pathogenic Bacteria from Camel's Urine

Background: Antibiotic resistance has been identified as a major hazard to public health in recent years. Using bacteriophages to control bacterial infections seems to be a safer alternative. Methicillin-resistant Staphylococcus aureus (MRSA) Escherichia coli (E.coli) can cause a variety of infections, ranging in severity from fairly insignificant to potentially fatal. Camels' urine has been utilized for therapeutic purposes and anecdotally hailed as a treatment for a variety of ailments for millennia. Alternative eradication strategies must be taken into consideration because of their increased antibiotic resistance, which frequently causes therapeutic failures. Potential candidates to control MRSA &amp;E.coli infections are bacteriophages and their lytic enzymes, lysins. The goal of the current study is to examine the existence of native bacteriophages in camel urine and determine whether they have any antibacterial properties against methicillin-resistant Staphylococcus aureus (MRSA) and Escherichia coli (E.coli). As well, as the impact of camel’s status on the presence of bacteriophages. Material and methods: In this study, we collected 80 camel urine samples from 6 different areas in the Taif region. The camel's urine was collected from healthy male and female (virgin, mother) camels aged 1–8 years, it has been divided into two groups with different natural feeding patterns G1:which grazes naturally on wild plants ( wild feeding)&amp;G2: which grazes naturally on wild plants, fodder, and barley(mixed feeding). Bacteriophages were isolated by spot assay Results: The phages had good lytic activity against Methicillin-resistant Staphylococcus aureus (MRSA) enterotoxigenic Escherichia coli (E.coli). When evaluated in vitro the greatest activity occurred 24 hours after phage infection. The highest activity of about 100% was achieved by virgin females out of eighty males and female samples. While the ratio represented in male and mother female, 70% 60% respectively. Conclusi

A Mixed-Methods Approach to Identify Farmers’ Perception and Practices Regarding Antibiotic Use in Vietnam

Antibiotic resistance (ABR) is one of the greatest global health concerns. The growth of food animal farming has challenged efforts to reduce unnecessary antibiotic use (ABU) and is linked to the rapid increases in ABR. This mixed-methods sociological study was conducted between 2016 and 2017, in a sample of 100 animal farmers in southern Vietnam, aiming to characterize their perception of ABU and identify factors influencing their practice. Data were collected from a structured questionnaire investigating characteristics of social demographics and farm style, farmers’ ABU perception and practices, sources of ABU information and the intention to reduce ABU. Generalized linear models were built to investigate potential influencing factors associated with ABU perception and practices. The results show a majority of farmers had an unfavourable perception of ABU. Only 13% correctly knew antibiotics were used for treating bacterial infections. The inappropriate practice of ABU for non-therapeutic purposes was found in almost two-thirds of the farmers (59.4%). Data from the multivariate analysis showed: (1) a significant association between an unfavourable perception of ABU and inappropriate practices, (2) an inverse influence of participation in training workshops to a favourable perception of ABU, but also (3) an inverse influence of participation in training workshops to inappropriate practices of ABU. The results suggest that the local training events that are usually put on by commercial companies do not assist farmers to effectively reduce ABU. On the contrary, these events seem to promote their use. We recognize the complexity of effectively managing appropriate ABU on farms in order to reduce ABR in Vietnam. We conclude that legislation and enforcement needs to be tightened to reduce sale of antibiotics to farmers without veterinarian prescription, and advertising and influence of commercial stakeholders needs to be highly moderated so that they do not unduly promote the unregulated use of antibiotics on farms. Household farmers are important stakeholders in the efforts to reducing ABU and preventing ABR, and therefore should be engaged more effectively.

The efficacy of anti-proteolytic peptide R7I in intestinal inflammation, function, microbiota, and metabolites by multi-omics analysis in murine bacterial enteritis.

Increased antibiotic resistance poses a major limitation in tackling inflammatory bowel disease and presents a large challenge for global health care. Antimicrobial peptides (AMPs) are a potential class of antimicrobial agents. Here, we have designed the potential oral route for antimicrobial peptide R7I with anti-proteolytic properties to deal with bacterial enteritis in mice. The results revealed that R7I protected the liver and gut from damage caused by inflammation. RNA-Seq analysis indicated that R7I promoted digestion and absorption in the small intestine by upregulating transmembrane transporter activity, lipid and small molecule metabolic processes and other pathways, in addition to upregulating hepatic steroid biosynthesis and fatty acid degradation. For the gut microbiota, Clostridia were significantly reduced in the R7I-treated group, and Odoribacteraceae, an efficient isoalloLCA-synthesizing strain, was the main dominant strain, protecting the gut from potential pathogens. In addition, we further discovered that R7I reduced the accumulation of negative organic acid metabolites. Overall, R7I exerted better therapeutic and immunomodulatory potential in the bacterial enteritis model, greatly reduced the risk of disease onset, and provided a reference for the in vivo application of antimicrobial peptides.

First assessment of the knowledge, attitudes, and practices of health actors in Togo and Ivory Coast in regard to antibiotic resistance

Background and Aim: Bacterial resistance to antibiotics has now become a threat to global public health. This study aimed to assess the knowledge, attitudes, and practices of health actors in relation to antibiotic resistance (ABR) in two African countries. Materials and Methods: A cross-sectional and descriptive questionnaire study was conducted in Ivory Coast and Togo from August 2020 to July 2021. Actors were interviewed both in person 63% (n = 141) and remotely due to COVID-19 restrictions. Qualitative variables were described by frequencies and quantitative variables by the mean and associated standard deviation. The bivariate analysis was conducted through the Chi-square test and exact Fisher test with an acceptable risk of 5%. Results: The results showed that 88% and 50% of the actors from Togo and Ivory Coast, respectively, had a good knowledge of ABR even if most of the stakeholders had limited knowledge of antibiotics that are banned or of critical importance in human and animal medicine. More than 75% of the actors had good perceptions in regard to ABR and these were significantly related to their profession. As for the factors leading to an increase in ABR, the interviewees perceived self-medication in humans as the main contributing factor. Approximately 70% of the actors admitted to following inadequate practices in terms of the use and/or distribution of antibiotics, and 58% and 46% of them used preventive antibiotic therapy in Togo and Ivory Coast, respectively. Similarly, in the two countries, 39% and 69% of the actors, respectively, claimed that they do not systematically use the antibiogram, and 69% and 61% of drug distributors, also respectively, admitted to occasionally selling antibiotics without a prescription. Finally, more than 80% thought that the authorities in their country did not communicate sufficiently about ABR. Among the actions that could help to combat ABR, actors considered the strengthening of controls on the distribution of antibiotics and the education of nonprofessionals on the importance of antibiotic preservation as priorities. Conclusion: Although this first study had some limitations, that is, the low number of surveyed actors and non-standardized questionnaire used, it revealed that health actors in Togo and Ivory Coast have a good knowledge and perception in regard to antibiotics and ABR, but also follow inadequate practices.

Whole-genome sequencing-based characteristics of Escherichia coli Rize-53 isolate from Turkey.

Urinary tract infections (UTIs) are one of the most common infectious diseases. Inappropriate and excessive administration of antibiotics has led to the increased antibiotic resistance in the pathogens that cause UTIs. This work focused on identifying genetic determinants of antibiotic resistance in a clinical isolate of UTI-causing Escherichia coli. A clinical isolate of E. coli resistant to β-lactam, tetracycline and aminoglycoside antibiotics was analyzed using whole-genome sequencing (WGS) to identify genes that contribute to its resistance. The clinical isolate was obtained from a urine sample of a UTI patient in Turkey and identified via 16S rDNA sequencing. Antimicrobial susceptibility test was performed for 17 antibiotics using VITEK® 2 and the results were confirmed using minimum inhibitory concentration assay. Whole-genome sequencing of the isolate was performed using Illumina sequencing and analyzed with bioinformatic tools for multilocus sequence typing, replicon types, virulence factors, and antimicrobial resistance genes. Whole-genome datum was submitted to the National Center for Biotechnology Information (NCBI; accession No. JAKSGM000000000). The isolate was only found to be resistant to piperacillin in the β-lactam class of antibiotics. While the isolate was also resistant to aminoglycoside and tetracycline antibiotics, it was sensitive to other antibiotics tested. Ten antibiotic resistance genes were identified in the genome of the isolate: blaOXA-1, blaOXA-2, aac(6')-II, aac(6')-Ib-cr, tetB, catB3, qacE, sitABCD, mdfA, and sul-2. Clonal subtype (ST) and serotype of the isolate were identified as ST2141 and O107/H39, respectively. Plasmid replicon typing was used to identify 5 plasmid types in the genome of E. coli Rize-53 (Col(BS512), IncC, IncIA, IncFIB(AP1918), and IncFII(pRSB107)); however, none of the resistance genes were encoded on the plasmid. Genetic determinants of resistance to tetracycline, β-lactam and aminoglycoside antibiotics were identified using WGS in a uropathogenic E. coli from ST2141 lineage and O107:H39 serotype, isolated in Turkey.

A core–shell 2D-MoS2@MOF heterostructure for rapid therapy of bacteria-infected wounds by enhanced photocatalysis

As the increasing antibiotics resistance of bacteria, pathogenic bacterial infections aggravate the skin wounds and prevent it from healing and even induce serious complications. Here, we constructed a core–shell interface electric field at the interface between Prussian blue (PB) metal organic framework (MOF) and two-dimensional MoS2 nanosheets by in-situ growth of MoS2 on the surface of MOF (MoS2@PBMOF), which drove the transfer of photo-excited electrons and promoted the separation of photoinduced electron-hole pairs. Additionally, the lower O2 adsorption energy of MoS2@PBMOF endowed the heterostructure with much stronger O2 adsorption ability than MoS2 alone, which provided more oxygen species to capture the photogenerated electrons and holes and thus produced more radical oxygen species (ROS). Meanwhile, the excellent photothermal property of the composite could regulate the release of iron ions from MoS2@PBMOF under light irradiation by hyperpyrexia. Hence, under 660 nm visible illumination for 20 min, the MoS2@PBMOF killed 99.73 % S. aureus and 99.58 % E. coli, which attributed to the synergy of local hyperthermia, abundant ROS, and released iron ions through bacterial membrane damage, protein leakage, and the oxidation of glutathione. Importantly, this composite could promote the healing of damaged tissues with good biosafety by promoting the production of hemoglobin. This work provides new insight into the practical application of promising strategy for environmental disinfection and treating bacterial wound infections without using antibiotics.

What role does organic fertilizer actually play in the fate of antibiotic resistome and pathogenic bacteria in planting soil?

Organic fertilizer increase antibiotic resistance genes (ARGs) and bacterial pathogens have widely documented. However, how organic fertilizer is involved in changing soil ARGs and pathogenic bacteria after long-term (≥5 years) application remains unclear. Herein, the ARGs and pathogenic bacteria were compared in organic fertilized soils (AF) and non-fertilized soils (NF), and the contribution of input sources (organic fertilizer, irrigation water, air and background soil) on soil ARGs also was determined in this study. Results showed that the abundances of some ARGs, such as vanR and aac(6')-I in AF, were significantly higher than these of NF (p<0.05). And a relatively higher abundance of potential pathogens, especially, Salmonella enterica and Stenotrophomonas maltophilia, in AF was observed. This indicated that organic fertilizer application can maintain a high level of some soil ARGs and pathogenic bacteria for at least 5 years. Traceability analysis unearthed that organic fertilizer application mainly increased its own contribution to soil ARGs from 1.16% to 9.05%, as well reduced the contribution of background soil, suggesting that the increase in soil ARGs may be partly attributable to organic fertilizer inputs. Notably, organic fertilizer application did not significantly alter the contribution ratio of input sources to microorganisms, but there was a clear change in the composition of soil microorganisms, which meant that the effect of the input source on the microorganism may emanate from other factors, rather than direct inputs. Subsequent structural equation demonstrated that organic fertilizer application significantly enhanced the effect of environmental factors on ARGs, and also indirectly increased the influence of communities on ARGs. Collectively, under the long-term fertilization, the role of organic fertilizers on soil ARGs not just stems from its own input, and also dominates the influence of environmental factors on ARGs. This study elucidates main causes for the difference in ARGs in AF vs. NF and enlightens actual role of organic fertilizer in them.

Functional insights of antibiotic resistance mechanism in Helicobacter pylori: Driven by gene interaction network and centrality-based nodes essentiality analysis

Increased antibiotic resistance in Helicobacter pylori (H. pylori), a major human pathogen, constitutes a substantial threat to human health. Understanding the pathophysiology and development of antibiotic resistance can aid our battle with the infections caused by H. pylori. The aim of this study is to discover the high-impact key regulatory mechanisms and genes involved in antimicrobial drug resistance (AMR). In this study, we constructed a functional gene interaction network by integrating multiple sources of data related to antibiotic resistant genes (number-77) from H. pylori. The gene interaction network was assortative, with a hierarchical, scale-free topology enriched in a variety of gene ontology (GO) categories and KEGG pathways. Using an iterative clustering methodology, we identified a number of communities in the AMR gene network that comprised nine genes (sodB, groEL, gyrA, recA, polA, tuf, infB, rpsJ, and gyrB) that were present at the deepest level and hence were key regulators of AMR. Further, an antibiotic-resistant gene network-based centrality analysis revealed superoxide dismutase (sodB) as a bottleneck node in the network. Our findings suggested that sodB is critically enriched in the cellular response to oxidative stress, removal of superoxide radicals, cellular oxidant detoxification processes, cellular component biogenesis, response to reactive oxygen species, urea metabolic process, nitrogen cycle metabolic process and reactive oxygen species metabolic process. We demonstrated how the sodB, which are involved in the response to reactive oxygen species, urea metabolic process, nitrogen cycle metabolic process, reactive oxygen species metabolic process, regulated by Fur gene/proteins, claim a major authority over regulation and signal propagation in the AMR.

Pathogens and Shift of Resistance in Early Infections after Operative Fracture Fixation.

Background: Surgical site infections (SSIs) remain a challenge for the healthcare system. During the last 30 years, the literature has shown an increase of gram-negative bacterial strains in multiple infectious sites and that cephalosporins have replaced penicillin as the gold standard in peri-operative antibiotic prophylaxis. This study aims to examine the recent bacterial spectrum in orthopedic early SSIs and to compare it with a historical cohort. Patients and Methods: Patients in a level 1 trauma center with an SSI within six weeks after open fixation of a fracture were analyzed in two adjacent periods from 2007 to 2012 (data pool 1; DP1) and 2013 to 2017 (data pool 2; DP2), retrospectively. The detected microbiologic pathogens and the associated resistograms from both time periods were compared. Results: Six hundred eighty-one smear tests and respective pathogens from the wounds of 463 patients (mean age, 62.6 ± 20 years) with SSIs were analyzed. The following pathogens were found most frequent: Staphylococcus epidermidis (DP1, 20.6%; DP2, 26.3%), Staphylococcus aureus (DP1, 27.1%; DP2, 16.5%), Enterococcus faecalis (DP1, 13.7%; DP2, 11.1%), Bacillus sp. (DP1, 3.0%; DP2, 5.3%), Escherichia coli (DP1, 5.1%; DP2, 4.1%), Pseudomonas aeruginosa (DP1, 3.7%; DP2, 2.5%). In DP2, there were lower primary early infection rates with Staphylococcus aureus than in DP1 (p = 0.002). In DP2, Staphylococcus epidermidis showed an oxacillin resistance in 90.6% and an increased resistance (79.8%; p = 0.069) to several classes of antibiotic agents compared to DP1. Conclusions: No bacterial shift toward gram-negative species was observed in this investigation. However, Staphylococcus epidermidis showed an increased antibiotic resistance in the more recent patient cohort. The incidence of SSIs with Staphylococcus aureus decreased substantially.

Fabrication of colloidal silver-peptide nanocomposites for bacterial wound healing

Increased antibiotic resistance has become a real healthcare challenge for humanity. Several novel approaches for the formation of nanomaterials have been developed to tackle different bacterial strains and wound disinfection. Short peptide modulated metal nanomaterials have gained attention because of their biocompatibility and ability to reduce metal ions in-situ to form nanoparticles. Here we have used a short peptide conjugate as a reducing and capping agent to make stabilized silver-peptide composite nanoparticles under mild UV light exposure. This photochemical method is one of the green approaches and reduces the toxic effects of chemicals that are often used in traditional synthetic strategies. These composite nanoparticles demonstrated promising activity against Escherichia coli and Staphylococcus aureus at an in-vitro level and have the ability to cure wounds disinfections in-vivo. Furthermore, these composite nanoparticles show excellent biocompatibility, and no side effects were observed in liver enzymes and organs, in a histopathology study. Such a simple strategy of sustainable supramolecular chemistry could help develop novel nanomaterials as potential antibiotic agents of the future.

Effect of sweet potato purple acid phosphatase on Pseudomonas aeruginosa flagellin-mediated inflammatory response in A549 cells.

The study was conducted to investigate the dephosphorylation of Pseudomonas aeruginosa flagellin (PA FLA) by sweet potato purple acid phosphatase (PAP) and the effect of the enzyme on the flagellin-mediated inflammatory response in the A549 lung epithelial cell line. The activity of sweet potato PAP on PA FLA was assayed at different pH (4, 5.5, 7, and 7.5) and temperature (25°C, 37°C, and 55°C) conditions. The release of interleukin-8 (IL-8) and the activation of nuclear factor kappa- light-chain-enhancer of activated B cells (NF-κB) in A549 cells exposed to PA FLA treated with or without sweet potato PAP was measured using IL-8 and NF-κB ELISA kits, respectively. The activation of toll-like receptor 5 (TLR5) in TLR5-overexpressing HEK-293 cells exposed to PA FLA treated with or without sweet potato PAP was determined by the secreted alkaline phosphatase-based assay. The dephosphorylation of PA FLA by sweet potato PAP was favorable at pH 4 and 5.5 and highest at 55°C. PA-FLA treated with the enzyme decreased IL-8 release from A549 cells to about 3.5-fold compared to intact PA FLA at 1,000 ng/mL of substrate. Moreover, PA-FLA dephosphorylated by the enzyme repressed the activation of NF-κB in the cells compared to intact PA FLA. The activation of TLR5 by PA-FLA was highest in TLR-overexpressing HEK293 cells at a substrate concentration of 5,000 ng/mL, whereas PA FLA treated with the enzyme strongly repressed the activation of TLR5. Sweet potato PAP has the potential to be a new alternative agent against the increased antibiotic resistance of P. aeruginosa and may be a new conceptual feed additive to control unwanted inflammatory responses caused by bacterial infections in animal husbandry.

The effect of cigarette smoke condensate (CSC) on Pseudomonas aeruginosa virulence and antibiotic sensitivity.

Despite a decline in tobacco smoking in the developed world, the developing world has witnessed an increase in such activity over recent years. An increase in antibiotic resistance has accompanied this increase in tobacco use, and we suggest that the two may be linked. This study aims to investigate the effect of cigarette smoke exposure on bacterial virulence and susceptibility to antibiotics. Pseudomonas aeruginosa passaged in the presence of Cigarette Smoke Condensate (CSC) exhibited reduced susceptibility towards Amikacin (p=0.02), Tobramycin (p=0.03) and Aztreonam (p=0.007) and was accompanied by changes in growth dynamics as exposure to CSC increased. These observed changes persisted after passaging bacteria in CSC-free medium for 10 days. The genotoxicity of CSC on P. aeruginosa was evaluated by the standard Comet assay, which demonstrated DNA damage in the P. aeruginosa genome in Passage 15 compared to the CSC-unexposed cells. Gene expression analysis on selected virulence and quorum sensing genes showed that both flagellar (fliC and fleR) and quorum sensing (lasI/R and rhII) genes were significantly up-regulated in Passage 15. Results confirm the genotoxic effect of cigarette smoke manifested in an increased antibiotic resistance, coupled with increased bacterial virulence SIGNIFICANCE AND IMPACT OF STUDY: This study is the first to elucidate a clear link between tobacco smoke residues and both increases in antibiotic resistance and the up-regulation of bacterial virulence markers.

BİR ÜÇÜNCÜ BASAMAK HASTANESİNDE PRİMER VE REVİZYON DİZ PROTEZİ AMELİYATLARINDAN SONRA İZOLE EDİLEN MİKROORGANİZMALARIN SIKLIĞININ VE ANTİBİYOTİK DİRENÇLERİNİN ZAMAN İÇERİSİNDE DEĞİŞİMİNİN DEĞERLENDİRİLMESİ

OBJECTIVE: Increased number of total knee arthroplasty has led to an increases the risk of periprosthetic joint infection (PJI) and other complications over time. Therefore, the current trends in infection and microbiology data are necessary to be understood to prevent and treat knee PJI. For this reason, we aimed to identify the course of bacterial species isolated after revision total knee arthroplasty and to investigate the change of antibiotic resistance over time.MATERIAL AND METHODS: Two groups of patients were evaluated, retrospectively. Group 1 consisted of patients who had surgery that caused the development of infection performed between 2005 and 2011 while group 2 consisted of patients between 2012 and 2018. The variation of isolated microorganisms species and their antibiotic resistances over time were investigated. Cefazolin (clindamycin in case of allergy) was the antibiotic used for routine prophylaxis between 2005 and 2018.RESULTS: Overall, 42 patients (43 knee joints) were included in the study. The most frequently isolated bacterium was Staphylococcus epidermidis while Staphylococcus aureus was the second most isolated bacterium in groups 1 and 2. An increased rate of gram-negative bacteria (Pseudomonas aeruginosa) isolation was observed in time. According to statistical analysis, a significant increase in antibiotic resistance to ciprofloxacin (p=0.0021), gentamicin (p=0.0001), tetracycline (p=0.043) and trimethoprim/sulfamethoxazole (p=0.0016) were observed over time. No increased antibiotic resistance observed over time against clindamycin (p=0.88) which we used in case of cefazoline allergy. Cefazoline resistance significantly decreased during 2012 and 2018 (p&amp;lt;0.0001). Vancomycin resistance was observed in only one patient.CONCLUSIONS: Our results and the literature has showed a steady increase in gram-negative bacteria isolation rates in patients with PJI. Therefore, it will become more necessary to use prophylactic antibiotic regimens including gram-negative bacteria in knee arthroplasty surgery. Although an increased resistance to ciprofloxacin, gentamicin, tetracycline and trimethoprim/sulfamethoxazole was found over time in the current study, these were not the antibiotics we used for routine prophylaxis. Instead of using cefazolin or clindamycin alone for prophylaxis, it is necessary to combine these anatibiotics with gentamicin.

Antibacterial Activity of Silver and Gold Particles Formed on Titania Thin Films.

Metal-based nanoparticles with antimicrobial activity are gaining a lot of attention in recent years due to the increased antibiotics resistance. The development and the pathogenesis of oral diseases are usually associated with the formation of bacteria biofilms on the surfaces; therefore, it is crucial to investigate the materials and their properties that would reduce bacterial attachment and biofilm formation. This work provides a systematic investigation of the physical-chemical properties and the antibacterial activity of TiO2 thin films decorated by Ag and Au nanoparticles (NP) against Veillonella parvula and Neisseria sicca species associated with oral diseases. TiO2 thin films were formed using reactive magnetron sputtering by obtaining as-deposited amorphous and crystalline TiO2 thin films after annealing. Au and Ag NP were formed using a two-step process: magnetron sputtering of thin metal films and solid-state dewetting. The surface properties and crystallographic nature of TiO2/NP structures were investigated by SEM, XPS, XRD, and optical microscopy. It was found that the higher thickness of Au and Ag thin films results in the formation of the enlarged NPs and increased distance between them, influencing the antibacterial activity of the formed structures. TiO2 surface with AgNP exhibited higher antibacterial efficiency than Au nanostructured titania surfaces and effectively reduced the concentration of the bacteria. The process of the observation and identification of the presence of bacteria using the deep learning technique was realized.

Acute and persistent effects of commonly used antibiotics on the gut microbiome and resistome in healthy adults.

SUMMARYAntibiotics are deployed against bacterial pathogens, but their targeting of conserved microbial processes means they also collaterally perturb the commensal microbiome. To understand acute and persistent effects of antibiotics on the gut microbiota of healthy adult volunteers, we quantify microbiome dynamics before, during, and 6 months after exposure to 4 commonly used antibiotic regimens. We observe an acute decrease in species richness and culturable bacteria after antibiotics, with most healthy adult microbiomes returning to pre-treatment species richness after 2 months, but with an altered taxonomy, resistome, and metabolic output, as well as an increased antibiotic resistance burden. Azithromycin delays the recovery of species richness, resulting in greater compositional distance. A subset of volunteers experience a persistent reduction in microbiome diversity after antibiotics and share compositional similarities with patients hospitalized in intensive care units. These results improve our quantitative understanding of the impact of antibiotics on commensal microbiome dynamics, resilience, and recovery.

Antibiotic Prescribing in Connection to Childbirth: An Observational Study in Two Districts in Lao PDR.

Overuse and misuse of antibiotics has frequently been reported for obstetric conditions and procedures, which may impact both the mother and the unborn baby and increase antibiotic resistance. This study aimed to investigate the antibiotic prescribing pattern in connection to childbirth in two districts in Lao PDR. It is a cross-sectional observational study. Antibiotic prescription data related to childbirth was collected via reviews of medical records in two district hospitals and five health centers in Lao PDR from September 2019 to November 2020. In total, antibiotic prescription data for 1777 women were extracted from their medical records. It was found that all women received antibiotics during in-patient care irrespective of delivery mode. When in hospital, 85.5% of the women who underwent a caesarean section got antibiotic treatment for 5 days and women who had a vaginal delivery usually had antibiotic treatment for one day or less. All the women got oral antibiotics for an additional 4–5 days upon discharge. Antibiotic prescription rate in connection to childbirth was very high in comparison with the WHO guidelines, and antibiotics were used extensively in the participating health facilities. Interventions to guide appropriate prescribing behavior in relation to childbirth are urgently needed in Lao PDR.

Antibacterial composite hydrogels of graphene quantum dots and bacterial cellulose accelerate wound healing.

The increased antibiotic resistance of pathogenic bacteria requires intense research of new wound healing agents. Novel wound dressings should be designed to provide wound disinfection, good moisture, and fast epithelization. In this study, bacterial cellulose (BC) was impregnated with graphene quantum dots (GQDs) for potential use in wound healing treatment. The BC was successfully loaded with approximately 11.7wt% of GQDs. The actual release of GQDs from new designed composite hydrogels were 13%. Novel GQDs-BC hydrogel composites are biocompatible and showed significant inhibition towards Staphylococcus aureus and Streptococcus agalactiae and bactericidal effect towards Methicillin-resistant Staphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa. The in vitro healing analysis showed significant migration of human fibroblasts after the GQDs-BC hydrogels application. Furthermore, after 72 h exposure to GQDs-BC, endothelial nitric oxide synthase, vascular endothelial growth factor A, matrix metallopeptidase 9, and Vimentin gene expression in fibroblast were significantly upregulated promoting angiogenesis. GQDs-BC hydrogel composites showed very good wound fluid absorption and water retention, which satisfies good dressing properties. All obtained results propose new designed GQDs-BC hydrogels as potential wound dressings.