Methicillin Resistant Staphylococcus Aureus

Purified isothiocyanates from cruciferous plants (Brassicacea, Syn. Cruciferae) plants were evaluated against 15 isolates of methicillin-resistant S. aureus isolated from diabetic foot-ulcer patients aiming the study of the potential usage of allyl-isothiocyanate, benzyl-isothiocyanate and 2-phenylethyl-isothiocyanate against this important bacteria. Disc diffusion and minimum inhibitory concentration methods were used to access the antimicrobial activity. The index (Ia) and rate (Ra) of the antibacterial activity for each compound were calculated. The results showed a highly dose-dependent compound and chemical structure antibacterial effectiveness. The results showed a strong relation between the chemical structure of isothiocyanates and its antibacterial effectiveness. The benzyl-isothiocyanate was the most effective with a minimum inhibitory concentration varying between 2.9 and 110 µg•mL −1 with an antibacterial activity rate up to 87%. Moreover, their antibacterial activity was mainly bactericidal. This study provides scientific evidence that isothiocyanates have an interesting biological value and must be considered as an important tool to be used against MRSA.

A duplex LightCycler PCR assay targeting the mecA gene and a Staphylococcus aureus-specific marker was used to test 165 S. aureus strains and 80 strains of other bacterial species. Within an assay time of 60 min plus 10 min for sample preparation, S. aureus as well as the presence or absence of the mecA gene was correctly identified.

Despite infection prevention efforts, neonatal intensive care unit (NICU) patients remain at risk of Methicillin-resistant Staphylococcus aureus (MRSA) infection. Modes of transmission for healthcare-associated (HA) and community-associated (CA) MRSA remain poorly understood and may vary by genotype, hindering the development of effective prevention and control strategies. From 2008-2010, all patients admitted to a level III NICU were screened for MRSA colonization, and all available isolates were spa-typed. Spa-type t008, the most prevalent CA- genotype in the United States, spa-type t045, a HA- related genotype, and a convenience sample of strains isolated from 2003-2011, underwent whole-genome sequencing and phylodynamic analysis. Patient risk factors were compared between colonized and noncolonized infants, and virulence and resistance genes compared between spa-type t008 and non-t008 strains. Epidemiological and genomic data were used to estimate MRSA importations and acquisiti...

Staphylococcus aureus is a common cause of infections that has undergone rapid global spread over recent decades. Formal phylogeographic methods have not yet been applied to the molecular epidemiology of bacterial pathogens because the limited genetic diversity of data sets based on individual genes usually results in poor phylogenetic resolution. Here, we investigated a whole-genome single nucleotide polymorphism (SNP) data set of health care-associated Methicillin-resistant S. aureus sequence type 239 (HA-MRSA ST239) strains, which we analyzed using Markov spatial models that incorporate geographical sampling distributions. The reconstructed timescale indicated a temporal origin of this strain shortly after the introduction of Methicillin, followed by global pandemic spread. The estimate of the temporal origin was robust to the molecular clock, coalescent prior, full/intergenic/synonymous SNP inclusion, and correction for excluded invariant site patterns. Finally, phylogeographic analyses statistically supported the role of human movement in the global dissemination of HA-MRSA ST239, although it was unable to conclusively resolve the location of the root. This study demonstrates that bacterial genomes can indeed contain sufficient evolutionary information to elucidate the temporal and spatial dynamics of transmission. Future applications of this approach to other bacterial strains may provide valuable epidemiological insights that may justify the cost of genome-wide typing.

The research on potential methanol extract from marine tunicate Pyura sp as antibacterial Methicillin-Resistant Staphylococcus aureus (MRSA) has been done from February to April 2017. This research was intended to know the potential of methanol tunicates extract of proposed tunicates as an antibacterial MRSA. Tunicates were collected from Barrang Lompo waters of Sangkarang Archipelago of South Sulawesi Indonesia. Samples were dried, then the active compound was extracted used methanol solvent according to a standard procedure elsewhere. Tunicate’s extract was prepared into three different concentrations: 10%, 15%, and 20%, were tested against MRSA bacteria. A test of inhibition zone was applied at 24 h and 48 h incubation time in order to determine the bioactivity of tunicate’s extract towards MRSA. The result indicates that crude extracts of tunicates P. Pyura sp at all concentration performs anti bacteria activity against MRSA. This study concluded that tunicate Pyura sp has bacte...

The aim of the study was to investigate the molecular epidemiology of community- associated MRSA in Primorsko-Goranska County of Croatia during a six-year period(2001-2007). In period from 2001 and 2007, 46 MRSA isolates were collected in Rijeka, strains were subjected to susceptibility testing according to CLSI guidelines, mecA gene detection and SCCmec typing as well as detection of PVL. Strains were typed by Pulse Field Gel Electrophoresis (PFGE) and spa typing. All isolates were susceptible to vancomycin, linezolid, mupirocin, nitrofurantoin, only one strain was resistant to fusidic acid and co-trimoxazole. Results of SCCmec typing showed the presence of SCCmec type IV in 26 MRSA strains, SCCmec type V in three strains, and 13 strains comprised SCCmec I. SCCmec type II and III were not observed. Four MRSA strains were non-typeable by applied SCCmec typing methods. PVL was detected in 4 strains, two SCCmec IV and two SCCmec V. PFGE analysis, grouped MRSA strains into six similarity groups and 18 singletons. Dominating spa types in this collection of strains were t015, with 15 strains, followed by t041(N=7), t051,(N=2 ), t2850(N=2), t008(N=2)and single isolates t441, t002, t448, t018, t019, t355, t390, t026, t449, t148. We also detected two new spa types, t3510 and t3509, respectively. This is the first report on SCCmec type V in Croatia, and, to our knowledge, first report of PVL-positive mehicillin-resistant Staphylococcus aureus SCCmec type V and t441(ST59-MRSA-V) in this part of Europe.

kindergartens, and schools 2. However, studies on the CA-MRSA prevalence are sporadic. HA-MRSA and CA-MR-SA can be distinguished by their genetic background, the resistance determinant Staphylococcal Cassette Chromosome mec (SCCmec), and the presence of Panton-Valentine leukocidin (PVL) 3. The aim of the present study was to investigate the molecular epidemiology of MRSA in Primorsko-Goranska County of Croatia during a six-year period (2001-2007). Prevalence of MRSA in Croatia in blood culture isolates was 36,3 %, in 2009 as presented by European Resistance Surveillance System (EARSS) website 4. Primorsko-Goranska County is situated in western part of Croatia, as seen at Figure 1., covering an area of 3.582 km². Largest city and county center is Rijeka, third largest city in Croatia. Public Health and Teaching Insti

Background: Community-acquired methicillinresistant Staphylococcus aureus (MRSA) is now the leading cause of superficial abscesses seen in the Emergency Department. Study Objectives: Our primary aim was to determine if an association exists between three predictor variables (abscess size, cellulitis size, and MRSA culture) and treatment failure within 7 days after incision and drainage in adults. Our secondary aim was to determine if an association exists between two clinical features (abscess size and size of surrounding cellulitis) and eventual MRSA diagnosis by culture. Methods: Logistic regression models were used to examine clinical variables as predictors of treatment failure within 7 days after incision and drainage and MRSA by wound culture. Results: Of 212 study participants, 190 patients were analyzed and 22 were lost to follow-up. Patients who grew MRSA, compared to those who did not, were more likely to fail treatment (31% to 10%, respectively; 95% confidence interval [CI] 8-31%). The failure rates for abscesses $ 5 cm and < 5 cm were 26% and 22%, respectively (95% CI À11-26%). The failure rates for cellulitis $ 5 cm and < 5 cm were 27% and 16%, respectively (95% CI À2-22%). Larger abscesses were no more likely to grow MRSA than smaller abscesses (55% vs. 53%, respectively; 95% CI À22-23%). The patients with larger-diameter cellulitis demonstrated a slightly higher rate of MRSA-positive culture results compared to patients with smaller-diameter cellulitis (61% vs. 46%, respectively; 95% CI À0.3-30%), but the difference was not statistically significant. Conclusion: Cellulitis and abscess size do not predict treatment failures within 7 days, nor do they predict which patients will have MRSA. MRSA-positive patients are more likely to fail treatment within 7 days of incision and drainage. Published by Elsevier Inc.

Methicillin-resistant Staphylococcus aureus (MRSA) remains a leading cause of bacterial infections worldwide, with a dwindling repertoire of effective antimicrobials active against it. This review aims to provide an update on novel anti-MRSA molecules currently under pre-clinical and clinical development, with emphasis on their mechanism of action. This review is limited to molecules that target the pathogen directly and does not detail immunomodulatory anti-infectives.

S. aureus is one of the most common bacterial diseases in poultry which causes drop in egg production, body weight loss, and lameness which is leading to carcass condemnation. Therefore, S. aureus has negative impact on the economy based on farming business alongside the foodborne illness causes (Andreasen, 2013). Moreover, S. aureus influences on the human health and causes food poisoning regarding to their enterotoxins productions (Han et al., 2013). Although diagnosing, detecting and genotyping of S. aureus are routinely processed among sick poultry (Andreasen , 2013) , alongside pigs, cows and goats, (Wang et al.,2017), the detection of S. aureus in ducks is too rare. However, in Egypt, the ducks are taking the second place of the poultry meat production (Radwan et al., 2019). On the other hand, research Article Abstract | Although Methicillin-resistant Staphylococcus aureus (MRSA) is one of the most widespread Bacteria causing infection over the world for poultry sector, MRSA in duck farms hasn't yet been investigated seriously. Thus, this study intensively investigates the prevalence of MRSA through 100 duck farms. S. aureus has been isolated from 21 farms. The classical enterotoxins (A-E) production plus toxic shock syndrome toxin (TSST-1) were screened by PCR, only four strains harbored sed gene. The antimicrobial resistance profiles were tested by agar diffusion assays showed that 90.5% of isolates exhibit multidrug resistance (MDR). All the tested isolates revealed 100% resistance towards penicillin G., ampicillin and cefoxitin. However, the resistances to kanamycin, tetracycline and gentamycin were 90.5%, 85.7% and 81% respectively. Additionally, Methicillin-resistant S. aureus (MRSA) isolates were identified by the presence of mecA gene, but all isolates were negative for mecC gene. The isolates were tested for the presence of four antimicrobial resistance genes including tetracycline resistance gene tetK that was detected in all isolates. Secondly, 90.5% of isolates carried erythromycin resistant gene ermB as well as gentamicin resistant gene, aacA-aphD. Finally, none of those isolates has carried vanA gene for vancomycin resistance. Consequently, continuous tracking the presence of MRSA in duck farms is very important to avoid developing a reservoir for antimicrobial resistances.

Conventional antibiotics are ineffective against non-replicating bacteria (for example, bacteria within biofilms). We report a series of halogenated phenazines (HP), inspired by marine antibiotic 1, that targets persistent bacteria. HP 14 demonstrated the most potent biofilm eradication activities to date against MRSA, MRSE, and VRE biofilms (MBEC=0.2-12.5 μM), as well as the effective killing of MRSA persister cells in non-biofilm cultures. Frontline MRSA treatments, vancomycin and daptomycin, were unable to eradicate MRSA biofilms or non-biofilm persisters alongside 14. HP 13 displayed potent antibacterial activity against slow-growing M. tuberculosis (MIC=3.13 μM), the leading cause of death by bacterial infection around the world. HP analogues effectively target persistent bacteria through a mechanism that is non-toxic to mammalian cells and could have a significant impact on treatments for chronic bacterial infections.

Candida albicans and Staphylococcus aureus are pathogens commonly isolated from bloodstream infections worldwide. While coinfection by both pathogens is associated with mixed biofilms and more severe clinical manifestations, due to the combined expression of virulence and resistance factors, effective treatments remain a challenge. In this study, we evaluated the activity of echinocandins, especially caspofungin, against mixed biofilms of C. albicans and methicillinresistant (MRSA) or methicillin-susceptible S. aureus (MSSA) and their effectiveness in vivo using the Galleria mellonella coinfection model. Although caspofungin (CAS) and micafungin (MFG) inhibited the mixed biofilm formation, with CAS exhibiting inhibitory activity at lower concentrations, only CAS was active against preformed mixed biofilms. CAS significantly decreased the total biomass of mixed biofilms at concentrations of $2 mg/ml, whereas the microbial viability was reduced at high concentrations (32 to 128 mg/ml), leading to fungus and bacterium cell wall disruption and fungal cell enlargement. Notably, CAS (20 or 50 mg/kg of body weight) treatment led to an increased survival and improved outcomes of G. mellonella larvae coinfected with C. albicans and MRSA, since a significant reduction of fungal and bacterial burden in larval tissues was achieved with induction of granuloma formation. Our results reveal that CAS can be a therapeutic option for the treatment of mixed infections caused by C. albicans and S. aureus, supporting additional investigation. IMPORTANCE Infections by microorganisms resistant to antimicrobials is a major challenge that leads to high morbidity and mortality rates and increased time and cost with hospitalization. It was estimated that 27 to 56% of bloodstream infections by C. albicans are polymicrobial, with S. aureus being one of the microorganisms commonly coisolated worldwide. About 80% of infections are associated with biofilms by single or mixed species that can be formed on invasive medical devices, e.g., catheter, and are considered a dissemination source. The increased resistance to antimicrobials in bacterial and fungal cells when they are in biofilms is the most medically relevant behavior that frequently results in therapeutic failure. Although there are several studies evaluating treatments for polymicrobial infections associated or not with biofilms, there is still no consensus on an effective antimicrobial therapy to combat the coinfection by bacteria and fungi.

Infections by microorganisms resistant to antimicrobials is a major challenge that leads to high morbidity and mortality rates and increased time and cost with hospitalization. It was estimated that 27 to 56% of bloodstream infections by C. albicans are polymicrobial, with S. aureus being one of the microorganisms commonly coisolated worldwide.

Staphylococcus aureus (S. aureus) represents a major threat to a broad range of healthcare and community associated infections. This bacterium has rapidly evolved resistance to multiple drugs throughout its antibiotic history and thus it is imperative to develop novel antimicrobial strategies to enrich the currently shrinking therapeutic options against S. aureus. This study evaluated the antimicrobial activity and therapeutic efficacy of oleic acid (OA) in a liposomal formulation as an innate bactericide against methicillin-resistant S. aureus (MRSA). In vitro studies showed that these OA-loaded liposomes (LipoOA) could rapidly fuse into the bacterial membranes, thereby significantly improving the potency of OA to kill MRSA compared with the use of free OA. Further in vivo tests demonstrated that LipoOA were highly effective in curing skin infections caused by MRSA bacteria and preserving the integrity of the infected skin using a mouse skin model. Moreover, a preliminary skin toxicity study proved high biocompatibility of LipoOA to normal skin tissues. These findings suggest that LipoOA hold great potential to become a new, effective, and safe antimicrobial agent for the treatment of MRSA infections.

The impact of prevention strategies and risk factors for early-onset (EOP) versus late-onset (LOP) ventilator-associated pneumonia (VAP) are still debated. To evaluate, in a multicenter cohort, the risk factors for EOP and LOP, as the evolution of prevention strategies. 7,784 patients with mechanical ventilation (MV) for at least 48 hours were selected into the multicenter prospective OUTCOMEREA database (1997-2016). VAP occurring between the 3rd and 6th day of MV defined EOP, while those occurring after defined LOPs. We used a Fine and Gray subdistribution model to take the successful extubation into account as a competing event. Overall, 1,234 included patients developed VAP (EOP: 445 (36%); LOP: 789 (64%)). Male gender was a risk factor for both EOP and LOP. Factors specifically associated with EOP were admission for respiratory distress, previous colonization with multidrug-resistant Pseudomonas aeruginosa, chest tube and enteral feeding within the first 2 days of MV. Antimicrob...

Introduction: Methicillin-resistant Staphylococcus aureus (MRSA) colonisation is an important source of healthcare-acquired infections. Reliable screening strategies for MRSA colonisation are essential for the timely implementation of infection control measures. Aim: This study determined reliable MRSA screening sites to predict colonisation in resource-limited settings and estimated the impact of missed MRSA cases when shifting from multi-to single-site screening. Methodology: A cross-sectional study was conducted in patients with positive MRSA surveillance cultures from the routinely screened sites (nasal, axillary, groin, and throat) from January 2009 to December 2019. Results: A total of 1906 screening tests were positive for MRSA cultures (n = 1345 patients). As a single site, the nasal cavity showed the highest MRSA detection, with a sensitivity of 66.8% (95% CI = 64-69) with 277.9 missed isolation days. Screening three or more anatomical sites detected 97-100% of MRSA cases, with 0-24.5 missed isolation days. Screening the axilla and groin separately or in combination showed a good clinical utility index (CUI) of >0.6 to <0.8, while an excellent CUI was obtained upon screening other site samples (>0.8). The combined nasal and throat cultures demonstrated a sensitivity of 93.2 (95% CI = 91-94) with 57.2 missed isolation days. Conclusion: Multi-site screening is the optimal strategy for minimising MRSA exposure within a healthcare facility. For active MRSA surveillance, a combination of nasal and throat cultures can provide a practical approach in low-resource settings compared to nasal sampling alone.

Staphylococcus aureus that are resistant to many antibiotics are known as as Methicillin-resistant Staphylococcus aureus (MRSA). Infections caused by MRSA can cause severe infection especially in immunocompromised individuals. Compared to ordinary Staphylococcus infections, MRSA infectios are more difficult to treat. This is because the strains of staphylococcus known as MRSA do not respond well to many common antibiotics. The objective of the study is to detect MRSA in Staphylococcus species isolated from various clinical samples. A retrospective study of all staphylococcus species was conducted. Total of 161 isolates were isolated from various samples. They were processed and identified by standard Microbiological procedures. The antibiotics susceptibility testing was performed by Kirby- Bauer disc diffusion method using CLSI guidelines. MRSA was detected by disc diffusion test using Cefoxitin (30μg) disc. Of 161 samples processed, 74 Methicillin-resistant Staphylococcus species were isolated. Methicillin resistance were found to be high in pus (41.8%) samples followed by urine 29(39.1%) and blood 14 (18.9%) and they showed higher sensitivity towards vancomycin followed by linezolid. Methicillin resistance in Staphylococcus species are increasing rapidly and becoming a major problem. Disk diffusion method can be routinely employed to detect these resistant strains to understand the drug resistance patterns of Methicillin resistance producing staphylococcus species.

The development of a new class of antibiotics to fight bacterial resistance is a time-consuming effort associated with high-cost and commercial risks. Thus, modification, conjugation or combination of existing antibiotics to enhance their efficacy is a suitable strategy. We have previously reported that the amphiphilic cyclic peptide [R 4 W 4 ] had antibacterial activity with a minimum inhibitory concentration (MIC) of 2.97 µg/mL against Methicillin-resistant Staphylococcus aureus (MRSA). Herein, we hypothesized that conjugation or combination of the amphiphilic cyclic peptide [R 4 W 4 ] with levofloxacin or levofloxacin-Q could improve the antibacterial activity of levofloxacin and levofloxacin-Q. Fmoc/tBu solid-phase chemistry was employed to synthesize conjugates of [R 4 W 4 K]-levofloxacin-Q and [R 4 W 4 K]-levofloxacin. The carboxylic acid group of levofloxacin or levofloxacin-Q was conjugated with the amino group of β-alanine attached to lysine in the presence of 2-(1H-benzotriazol-1-yl)-1,1,3,3-tetramethyluronium hexafluorophosphate (HBTU) and N,N-diisopropylethylamine (DIPEA) for 3 h to afford the products. Antibacterial assays were conducted to determine the potency of conjugates [R 4 W 4 K]-levofloxacin-Q and [R 4 W 4 K]-levofloxacin against MRSA and Klebsiella pneumoniae. Although levofloxacin-Q was inactive even at a concentration of 128 µg/mL, [R 4 W 4 K]-levofloxacin-Q conjugate and the corresponding physical mixture showed MIC values of 8 µg/mL and 32 µg/mL against MRSA and Klebsiella pneumonia, respectively, possibly due to the activity of the peptide. On the other hand, [R 4 W 4 K]-levofloxacin conjugate (MIC = 32 µg/mL and MIC = 128 µg/mL) and the physical mixture (MIC = 8 µg/mL and 32 µg/mL) was less active than levofloxacin (MIC = 2 µg/mL and 4 = µg/mL) against MRSA and Klebsiella pneumoniae, respectively. The data showed that the conjugation of levofloxacin with [R 4 W 4 K] significantly reduced the antibacterial activity compared to the parent analogs, while [R 4 W 4 K]-levofloxacin-Q conjugate was more significantly potent than levofloxacin-Q alone.

Background: The rapid emergence and spread of community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) has raised considerable public health concern in both developed and developing countries. The current study aimed to address the extent of this phenomenon in healthy preschool children of a developing country. Materials and Methods: We conducted a prospective study from April 2013 to March 2014 on 410 healthy 2-6 years old preschool children in Isfahan, Iran. Demographic medical data and nasal samples were collected from the participating children. Isolates were identified as S. aureus and MRSA based on microbiological and molecular tests, including the presence of eap and mecA genes. Results: The overall prevalence of S. aureus and CA-MRSA nasal carriage was 28% (115/410) and 6.1% (25/410), respectively. The identity of isolates was confirmed by molecular assay. The factors that were independently associated with nasal carriage of S. aureus were: Children crowding in day-care nurseries and income level of families. A total of 20/90 (22.2%) of methicillin-susceptible S. aureus and all 25 CA-MRSA displayed multiple drug resistance to 3-8 antibiotics. Conclusions: The current report reflects issues and concerns that the high rate of colonization by CA-MRSA in Iranian healthy children provides obliging evidence that MRSA have established a foothold in the community and are emerging as important health threatening pathogens. It is suggested that we need more effective infection control measures to prevent transmission of nasal CA-MRSA in healthy preschool children.

In order to study the micro-epidemiology of meticillin-resistant Staphylococcus aureus (MRSA) effectively, the molecular typing method used must be able to distinguish between different MRSA strains. Pulsed-field gel electrophoresis (PFGE) can detect small genetic differences but is limited in its potential to distinguish isolates within a major lineage. Whole-genome sequencing (WGS) provides sufficient resolution to support or exclude links between otherwise indistinguishable isolates, but lacks the practical utility of conventional typing methods. To explore the utility of WGS in a hierarchical approach with PFGE to help establish possible sources of MRSA cross-transmission in the intensive care setting. Possible transmission routes from donor to recipient via the hands of staff, the air or environmental surfaces were identified. Focused molecular typing used PFGE to explore these transmission hypotheses. WGS was applied when an acquisition event involved a common PFGE pulsotype. ...

Staphylococcus aureus (SA) is the most common cause of skin and soft tissue infections (SSTIs) and nosocomial infections. In developed countries there is a major concern about the rise of community-associated methicillin-resistant SA (CA-MRSA), but data from developing countries are scarce. In this study we describe the prevalence and antibiotic susceptibility of CA-MRSA and healthcare-associated MRSA (HA-MRSA) in a district hospital from rural India. We identified 119 CA-SA infections and 82 HA-SA infections. The majority of infections were SSTI, and the proportion of MRSA in CA-SA and HA-SA infections was 64.7% and 70.7%, respectively. The proportion of CA-MRSA in children &lt;5 years was 73.7%. We did not observe any linezolid or vancomycin resistance. CA-SA had high levels of resistance to ciprofloxacin and low levels of resistance to chloramphenicol, doxycycline, rifampicin, and clindamycin. CA-MRSA had higher proportion of resistance to ciprofloxacin, erythromycin, gentamicin,...

We evaluated the antibacterial activity of the organic extracts (n-hexane, acetone and methanol) from the fruit of Artocarpus heterophyllus Lam. against Staphylococcus aureus, (methicillin-susceptible Staphylococcus aureus [MSSA]). The extract that demonstrated the greatest activity was that of acetone, with a minimum inhibitory concentration (MIC) value of 0.375 mg/ml against S. aureus MSSA. The acetone extract was further fractionated by means of open-column chromatographic methods into different fractions, and it was found that the F3 fraction was the most active. An active compound against MSSA and methicillin-resistant Staphylococcus aureus bacteria was isolated from this fraction; this compound was identified through spectroscopic methods of 1 H and 13 C nuclear magnetic resonance as artocarpesin.

This is a critical abstract of an economic evaluation that meets the criteria for inclusion on NHS EED. Each abstract contains a brief summary of the methods, the results and conclusions followed by a detailed critical assessment on the reliability of the study and the conclusions drawn. Health technology The study compared linezolid and vancomycin for the treatment of nosocomial pneumonia (NP) caused by methicillinresistant Staphylococcus aureus (MRSA). The linezolid regimen included linezolid 600 mg plus aztreonam every 12 hours (q12h), while the vancomycin regimen was vancomycin 1,000 mg plus aztreonam q12h. Type of intervention Treatment. Economic study type Cost-effectiveness analysis. Study population Patients were included in the study if it was likely that they had NP only and no other forms of non-NP. As there was no International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9CM) code that differentiated NP from community-acquired pneumonia, an algorithm was created to narrow the universe of patients with any diagnosis of pneumonia on admission to hospital, to a sample of patients who were most likely to have NP only. Admissions associated with a principal diagnosis of pneumonia were excluded, as were certain secondary diagnoses of pneumonia. Patients were excluded if their length of stay was less than 7 days or more than 21 days. Admissions for immunocompromised states and admissions of patients younger than 16 years of age were also excluded. Setting The setting was secondary care. The economic study was carried out in the mid-Atlantic region of the USA. Dates to which data relate The effectiveness data were taken from a study published in 2003. The dates to which the resources and prices related were not reported. Source of effectiveness data The effectiveness data were derived from a review of the literature. Modelling A decision-analytic model was used to compare the costs and effectiveness of linezolid and vancomycin.

Infection stems from complex interactions between a host, pathogen, and the environment. 1 Among various infections, cardiac infections are life threatening and can affect all parts of the heart including its valves, endocardium, myocardium, and pericardium. 2 Nosocomial infections are the main cause of morbidity and mortality among the patients undergoing cardiac surgery. 3 Major causes of nosocomial infections in patients undergoing cardiac surgery are the presence of major surgical wounds and frequent use of invasive monitoring devices, which affect the normal host defense mechanisms. 4 The most common pathogens involved in cardiac infections are S. aureus, viridians streptococci, coagulase negative staphylococci, and gram-negative bacilli. 5,6 Sternal infections are caused by coagulase-negative staphylococci (CONS). 7 The other predominant aerobic Gram-positive bacteria in cardiovascular infections is S. aureus. 8,9 S. aureus is the most common pathogen in both community and hospital-associated infections. 10 After major heart surgery, S. aureus is the main cause of surgical site infection (SSI) with the patient's endogenous microbiota as the principal source. 11 MRSA is a special strain of the S. aureus that has developed antibiotic resistance, first to penicillin since 1948s, and later to methicillin and related anti staphylococcal drugs (such as flucloxacillin, nafcillin, and oxacillin). MRSA are resistant to penicillins, cephalosporins, monobactams, and carbapenems, cephems, and β-lactams and β-lactamase inhibitor

Background: Enterococci normally inhabit the intestinal tract of humans and are also a potential pathogen in causing nosocomial infections. The increase in antibiotic resistance and transfer of antibiotic resistance gene to Staphylococcus aureus (S. aureus) due to co-colonization has increased its importance in research. The aim of the study was to evaluate local epidemiology of nasal and rectal colonization with Enterococcus faecalis (E. faecalis) and Enterococcus faecium (E. faecium) in patients of Paediatrics Intensive Care Unit (PICU) and correlation with clinical and socioeconomic factors. Methods: The nasal and perirectal swab samples were collected from 110 patients admitted in PICUs of three tertiary care hospitals of Rawalpindi Medical College, Pakistan. The identification of enterococci was done by biochemical tests and by PCR for ddl, vanA and vanB genes. Antibiotic susceptibility testing was performed by disc diffusion and MICs were determined for vancomycin, tetracycline, ciprofloxacin and oxacillin only. Results: Out of 220 nasal and perirectal samples, 09 vancomycin-resistant enterococci (VRE) and 76 vancomycinsusceptible enterococci (VSE), consisting of 40 E. faecalis and 45 E. faecium were isolated. PCR successfully identified both species with ddl primers and VRE with vanA primer. With disc diffusion method, all isolates were resistant to most of the antibiotics tested except linezolid, quinupristin/dalfopristin, teicoplanin and vancomycin. VRE showed resistance to teicoplanin and vancomycin both and none was resistant to linezolid and quinupristin/dalfopristin. Generally, E. faecium isolates were more resistant than E. faecalis. MICs of vancomycin for nasal and perirectal VRE were 512 mg/L and 64 to 512 mg/L respectively. VRE were more in patients with prolonged hospitalization, from urban localities and those having pneumonia. Conclusion: Present study reveals high colonization and antibiotic resistance in enterococcal isolates from nasal and perirectal area. Nasal colonization by enterococci in PICU is more alarming as VRE may cause infection and can transfer this resistance gene to other microorganisms like S. aureus.

Bone infection, also called osteomyelitis, can result when bacteria invade a bone. Treatment of osteomyelitis usually requires surgical debridement and prolonged antimicrobial therapy. The rising incidence of infection with multidrug-resistant bacteria, in particular methicillin-resistant staphylococcus aureus (MRSA), however, limits the antimicrobial treatment options available. Silver is well known for its antimicrobial properties and is highly toxic to a wide range of microorganisms. We previously reported our development of biocompatible, biodegradable, nanofibrous scaffolds that released silver ions in a controlled manner. The objective of this study was to determine the efficacy of these scaffolds in treating or preventing osteomyelitis. To achieve this objective, antimicrobial efficacy was determined using a 3D coculture system of human adipose-derived stem cells (hASC) and MRSA. Human ASC were seeded on the scaffolds and induced to undergo osteogenic differentiation in both the absence and presence of MRSA. Our results indicated that the silver ion-releasing scaffolds not only inhibited biofilm formation, but also supported osteogenesis of hASC. Our findings suggest that these biocompatible, degradable, silver ion-releasing scaffolds can be used at an infection site to treat osteomyelitis and/or to coat bone implants as a preventative measure against infection postsurgery.

Bone infection, also called osteomyelitis, can result when bacteria invade a bone. Treatment of osteomyelitis usually requires surgical debridement and prolonged antimicrobial therapy. The rising incidence of infection with multidrug-resistant bacteria, in particular methicillin-resistant staphylococcus aureus (MRSA), however, limits the antimicrobial treatment options available. Silver is well known for its antimicrobial properties and is highly toxic to a wide range of microorganisms. We previously reported our development of biocompatible, biodegradable, nanofibrous scaffolds that released silver ions in a controlled manner. The objective of this study was to determine the efficacy of these scaffolds in treating or preventing osteomyelitis. To achieve this objective, antimicrobial efficacy was determined using a 3D coculture system of human adipose-derived stem cells (hASC) and MRSA. Human ASC were seeded on the scaffolds and induced to undergo osteogenic differentiation in both the absence and presence of MRSA. Our results indicated that the silver ion-releasing scaffolds not only inhibited biofilm formation, but also supported osteogenesis of hASC. Our findings suggest that these biocompatible, degradable, silver ion-releasing scaffolds can be used at an infection site to treat osteomyelitis and/or to coat bone implants as a preventative measure against infection postsurgery.

The aim of this survey was to describe the incidence, epidemiology, microbiology, risk factors and outcome of medical care related laboratory-confirmed bloodstream infections (LCBIs) observed during a twelve-month prospective study in a Paediatric Teaching Hospital in Turin, Italy. Inclusion criteria were clinical signs of sepsis and positivity of one or more of the following tests: blood culture, polymerase chain reaction for bacterial and fungal DNA on blood, and culture on intravascular device tips. In all, 140 episodes of sepsis were documented in 131 children: 37 (26.4%) were healthcare outpatient-associated, 91 (65.0%) healthcare-associated and 12 (8.6%) community-acquired. The overall incidence of healthcare-associated LCBIs was 13.6/1,000 hospitalized patients and incidence density 1.4/1,000 inpatient days. The overall mortality was 3.9%. Forty-seven (36.7%) episodes involved newborns and 107 (83.6%) episodes were observed in children with an indwelling central venous cathet...

To study the efficacy of bagged larvae on wound debridement compared with conventional treatment. Randomized, multicenter, controlled, prospective phase 3 trial with blinded assessment of outcome measures by a single observer. Two hospital referral centers in Caen and Lyon, France. Random sampling of 119 patients with a nonhealing, sloughy wound 40 cm(2) or smaller, less than 2 cm deep, and an ankle brachial index of 0.8 or higher. During a 2-week hospital stay, patients received either maggot debridement therapy (MDT) or conventional treatment. At discharge, conventional dressings were applied and a follow-up visit occurred at day 30. Percentage of slough in wounds at day 15. There was a significant difference between groups at day 8 (54.5% in the MDT group and 66.5% in the control group) (P = .04). The mean percentage of slough at day 15 was 55.4% in the MDT group and 53.8% in the control group (P = .78). Although MDT shows no significant benefit at day 15 compared with convention...

Antibiotic resistance poses a global health crisis, limiting the efficacy of available therapeutic agents and hindering the development of new antibiotics. The pharmaceutical industry's waning interest in antibiotic production further exacerbates this challenge. Addressing antibiotic resistance demands innovative solutions. Here, we explore the application of CRISPR-Cas-based antimicrobials as a pioneering approach to combat multidrug resistance. Our study focuses on the methicillin-resistant clinical Staphylococcus aureus (MRSA), a significant clinical threat. Utilizing CRISPR/Cas9 technology, we aimed to concurrently target methicillin (mecA), gentamicin (aacA), and ciprofloxacin (grlA, grlB) resistance genes, thereby altering the resistance profile and enhancing sensitivity to antibiotics. We engineered CRISPR plasmids containing sgRNAs specific to the target regions, which were subsequently electroporated into MRSA strains. Real-time Polymerase Chain Reaction (RT-PCR) assessed changes in resistance gene expression, while disk diffusion and broth microdilution methods determined alterations in resistance status. Western blotting analyzed changes in PBP2a expression, and Sanger sequence analysis confirmed mutations in target regions. Results revealed a statistically significant 1.5-fold decrease in mecA gene expression, 5.5-fold decrease in grlA gene, 6-fold decrease in grlB gene, and 4-fold decrease in aacA gene compared to the wild type strain, as determined by RT-PCR. Antibiotic susceptibility tests demonstrated the suppression of mecA, grlA, grlB, and aacA genes, resulting in the reversal of resistance to beta-lactam, quinolone, and aminoglycoside antibiotics. Western blot analysis showed 70% decrease in PBP2a expression, indicating the breakdown of beta-lactam resistance. Sanger sequence analysis confirmed point mutations in grlB and aacA genes, along with three-base mutations in grlA and mecA genes. Our findings underscore the potential of CRISPR/Cas9 technology to mitigate antibiotic resistance, offering a transformative strategy to restore the efficacy of existing antibiotics in the face of multidrug-resistant pathogens. .

Objective: In this study, it was aimed to investigate in vitro activity of moxifl oxacin and rifampicin on biofi lm formation by clinical MRSA isolates. Background: Methicillin resistant Staphylococcus aureus (MRSA) strains could be the causative agent in chronical and medical device associated infections by biofi lm formation. Methods: Moxifl oxacin and rifampicin MIC values of 98 MRSA clinical isolates were determined by microdilution method. Biofi lm formation of all isolates was determined in 96-well microplates by using spectrophotometric method. Effects of MIC and sub-inhibitory concentrations (1/2 and 1/4 MIC) of antibiotics on biofi lm formation were examined in 46 strong biofi lm producer strains. Results: Biofi lm production decreased in 37 and 44 isolates at all studied concentrations of moxifl oxacin and rifampicin, respectively. Biofi lm production increased in six isolates with moxifl oxacin and in two isolates with rifampicin. Coclusion: Biofi lm inhibitory effect of rifampicin was found to be stronger than moxifl oxacin in the examined strains. The studied antimicrobials also induced biofi lm formation in some strains. Results of this study may help to evaluate the effects of these antibiotics on biofi lm formation of clinical MRSA strains and to control the antibiotic resistance in clinical settings (Tab. 2, Ref. 25).

objECtIvE. Because of the improvements in cardiac transplantation technology, pharmacology, and diagnostic imaging, the survival rate of patients who have undergone heterotopic heart transplantation has significantly increased, which makes postoperative evaluation of these patients increasingly important. Monitoring patients who have undergone heterotopic heart transplantation is technically more demanding than those who have undergone orthotopic heart transplantation because it is more difficult to monitor two hearts beating in one chest. In this article, we describe and evaluate cardiac and vascular anatomy and the status of the lungs in patients who have undergone heterotopic heart transplantation. ConClusIon. ECG-gated cardiac CT has proven to be particularly important in evaluating the complex anatomy and anastomoses of the donor and recipient hearts as well as the postoperative follow-up status of the two hearts, the cardiac arteries and great vessels, and the lungs, ultimately contributing to the prolonged survival of heterotopic heart transplantation patients.

Resumen Tratar con antibióticos una TAV, proceso intermedio entre colonización y neumonía asociada al ventilador (NAV), reduciría la incidencia de NAV y sus consecuencias. Métodos: seguimiento clínico diario y cultivos cuantitativos rutinarios de aspirado traqueal (CRAT) bisemanales hasta el destete en 323 pacientes en ventilación mecánica. Cuando se sospechó clínicamente infección (2/3 criterios), si había infiltrado radiográfico nuevo, se diagnosticó NAV y se practicó lavado broncoalveolar (LBA) y sin infiltrado nuevo, se diagnosticó TAV, se consideraron los aislamientos del LBA positivos (≥ 10 4 unidades formadoras de colonias (ufc)/ml) para la NAV) y del CRAT positivos (≥ 10 3 y < 10 6 ufc/ ml (bajo recuento) y ≥ 10 6 ufc/ml (alto recuento)) para TAV. Resultados: 443 de 2.309 radiografías mostraban ausencia de infiltrado o infiltrado difuso estable; 92 cumplían criterios de TAV, 13 de éstas, 12 con CRAT ≥ 10 6 ufc/ml, tuvieron una NAV en los siguientes 3 días (12 con cultivo de LBA ≥10 4 ufc/ml). En estas NAV, 11/15 (73.3%) de los patógenos coincidían con los de la TAV precedente. Desde otro punto de vista, 10 TAVs ocurrieron durante la semana posterior a una NAV, solo 4/12 (33.3%) patógenos de estas coincidían con los de la TAV, p=0.045 comparando con TAV precediendo a NAV. Setenta TAVs no tuvieron relación temporal con NAVs. Discusión: este estudio sugiere que tratar con antibióticos las TAVs podría prevenir una NAV en 14% de los casos, exponiendo a un uso innecesario al 86%, lo cual limitaría fuertemente la conveniencia de tratar las TAVs para prevenir las NAVs.

This study targeted Staphylococcus aureus (S. aureus)-mastitis of bovine as a possible source of livestock-associated methicillin-resistant Staphylococcus aureus (MRSA), to describe clinical signs of mastitis associated with MRSA and methicillin-sensitive Staphylococcus aureus (MSSA). The study area was the Gharbia and Kafrelsheikh governorates, in the central and northern regions of the Egyptian Delta. Clinical examination of animals was performed to detect clinical mastitis (CM) and clinically normal cases were tested by the California mastitis test (CMT) to identify subclinical mastitis (SCM). Accordingly, 38 mastitis cases (68 infected quarters) were detected. Milk samples were collected aseptically and were cultured on Baird Parker agar. Fifty nine Gram-positive cocci-shaped isolates were selected and preserved. In addition, 33 Staphylococcus spp. isolates originated from bovine mastitis at the same study area were obtained from Animal Health Research Institute (AHRI). The cocc...

transfusions) SSD patients at Children's Hospital of New Orleans were studied. Seven controls (not all age-matched) were used. Peripheral blood mononuclear cells were isolated by Ficoll centrifugation, cultured at 37uC with a final concentration of 10 5 cells/mL in RPMI-1640 having no Arg or glutamine and 40% autologous plasma or fetal calf serum (FCS). Arg and PHA were later added. Cells were cultured in triplicate. Cells were pulsed with 3 H thymidine and the isotopes's incorporation measured. Summary of Results: FCS resulted in high background, so autologous plasma was used in subsequent experiments. Results are shown in the following graph as means 6 SEM: Conclusion: Both patient and control cells showed increased levels of mitogenic response after addition of Arg, with the response in the patient group being much greater. Because of low N, the changes were not significant. The greater than normal mitogenesis in SSD with/without Arg appears to support the statement that SSD is a chronic inflammatory state and also suggests that Arg supplementation may benefit these patients by enhancing immune responsiveness.

Background: Invasive methicillin-resistant Staphylococcus aureus (MRSA) and methicillin-sensitive Staphylococcus aureus (MSSA) infections are major causes of numerous neonatal intensive care unit (NICU) outbreaks. There have been increasing reports of MRSA outbreaks in various neonatal intensive care units (NICUs) over the last decade. Our objective was to review the experience of Staphylococcus aureus sepsis in our NICU in the last decade and describe the trends in the incidence of Staphylococcus aureus blood stream infections from 2000 to 2009. Methods: A retrospective perinatal database review of all neonates admitted to our NICU with blood cultures positive for Staphylococcus aureus from (Jan 1 st 2000 to December 31 st 2009) was conducted. Infants were identified from the database and data were collected regarding their clinical characteristics and co-morbidities, including shock with sepsis and mortality. Period A represents patients admitted in 2000-2003. Period B represents patients seen in 2004-2009. Results: During the study period, 156/11111 infants were identified with Staphylococcus aureus blood stream infection: 41/4486 (0.91%) infants in Period A and 115/6625 (1.73%) in Period B (p < 0.0004). Mean gestation at birth was 26 weeks for infants in both periods. There were more MRSA infections in Period B (24% vs. 55% p < 0.05) and they were associated with more severe outcomes. In comparing the cases of MRSA infections observed in the two periods, infants in period B notably had significantly more pneumonia cases (2.4% vs. 27%, p = 0.0005) and a significantly higher mortality rate (0% vs. 15.7%, p = 0.0038). The incidences of skin and soft tissue infections and of necrotizing enterocolitis were not significantly changed in the two periods. Conclusion: There was an increase in the incidence of Staphylococcus aureus infection among neonates after 2004. Although MSSA continues to be a problem in the NICU, MRSA infections were more prevalent in the past 6 years in our NICU. Increased severity of staphylococcal infections and associated rising mortality are possibly related to the increasing MRSA infections with a more virulent community-associated strain.

Aim: Methicillin-resistant Staphylococcus (MRSA) is a public and occupational health concern, both in community and healthcare settings. In recent years, communityacquired MRSA (CA-MRSA) has emerged as a major causative agent of infections in individuals with no health care exposure or any of the classical risk factors associated with infections. Environmental surfaces frequently touched by hands play a role in the transmission of CA-MRSA, where inanimate objects are considered potential reservoirs and the source of MRSA infections. The purpose of this study was to examine the prevalence of MRSA on environmental surfaces inside a university campus. Methods and Results: A total of 1078 high-touch surface samples were collected from door handles, light switches, desks, keyboards and restroom surfaces. MRSA isolates were identified and confirmed by PCR, utilizing the Staph. aureus nuc and mecA genes. Antibiotic resistance profiles were determined using disc diffusion and minimum inhibitory concertation methods. In addition, the ability to form biofilms was investigated by the 96-well plate microdilution technique. PCR assays were performed to detect enterotoxin and antibiotic-resistant genes. The genetic diversity of MRSA was determined through multi-locus sequence typing (MLST), spa and agr typing methods. The overall contamination of Staph. aureus and MRSA was 14.6% (157/1078) and 2.8% (30/1078), respectively. The highest rate of MRSA contamination was detected in restroom sinks and door handles. All MRSA isolates were MDR, with the highest resistance observed was against trimethoprim-sulfamethoxazole. Most MRSA isolates (29/30, 97%) carried at least one gene encoding for staphylococcal enterotoxins (SE), with 10 different SE genotypes were observed. A total of 16 different spa types were detected among the 30 MRSA isolates. Multi-locus sequence typing revealed that 21 MRSA isolates belonged to eight known sequence types (ST), while nine isolates were novel strains. The most detected ST and spa types were ST22 and t223, respectively. Agr types I and III were represented in 28 out of the 30 isolates. The majority of the isolates carried SCCmec type IV, but only one isolate was positive for PVL. Conclusions: Our findings signify the potential of the high-touch surfaces in harbouring and transmitting MRSA to campus staff and students. Thus, the implementation of effective prevention measures outside the healthcare setting is needed to reduce the risk of acquiring CA-MRSA infections.

Background. Effective preventive measures can curb the spread of hospitalacquired infections (HAIs) and multidrug-resistant organisms (MDROs). However, the impact of coronavirus disease 2019 (COVID-19) and measures taken during it on these infections remains unclear. This study aimed to evaluate the impact of COVID-19 pandemic on HAIs and MDROs and compare it to seasonal influenza. Methods. A retrospective cohort study that used prospectively collected data from a tertiary referral hospital in Haifa, Israel. The study spanned from 2016 to 2021 and compared the period before and after COVID-19 and the influenza season (December-February) and the non-influenza season (March-November) in terms of the rate of hospital-acquired bloodstream infections (HA-BSI), MDROs, and Clostridium difficile infections (CDI) per 10,000 hospital days (HD). The study also measured the rate of central line-associated BSI (CLABSI) per 1,000 catheter days (CD) and the hand hygiene compliance (HHC) rates. Results. During the COVID-19 period, HAIs and MDROs decreased compared to before: methicillin-resistant Staphylococcus aureus (4.2 vs. 6.9/10,000 HD; p< 0.001), carbapenem-resistant Acinetobacter baumani (2.2 vs. 3.1/10,000 HD; p=0.02), and nosocomial CDI (3 vs. 4.6/10,000 HD; p< 0.001). However, there were higher rates of carbapenem-resistant Enterobacteriaceae (4.6 vs. 2.7/10,000 HD; p< 0.001) and HA-BSI (29.7 vs. 27.3/10,000 HD; p=0.006) in the COVID-19 period. CLABSI rates were not significantly different (2.3 vs. 2.7/1000 CD; p=0.910). HHC rates were 70% in both periods (p=0.151), and there were no significant differences in rates of MDROs, CDI, HA-BSI, or CLABSI (p=0.233, 0.675, 0.267, and 0.563, respectively) between influenza and non-influenza seasons. The median acquisition rate of multi-drug resistant organisms and Clostridium difficile infections before and during the COVID-19 pandemic and during or between influenza seasons Conclusion. During the COVID-19 period, there was a significant decrease in rates of HAIs and MDROs, accompanied by an increase in CRE rates, which could be attributed to the nationwide increase in CRE rates in Israel since 2016. The decrease in these infections was not attributable to improvement in HHC, suggesting that other factors may be involved. Furthermore, influenza did not show an impact on these infections, likely due to the particular way it is perceived by healthcare workers.

Rich pharmacokinetic data on vancomycin in critically-ill patients are lacking. The purpose of this study was to evaluate the pharmacokinetics of vancomycin in this population using rich pharmacokinetic sampling. Nineteen critically-ill patients received individualized vancomycin doses by intermittent infusion to achieve target trough concentrations (15-20 mg/L). Blood samples were collected following the 3 rd or later dose of vancomycin. Serial blood samples were collected at 30 minutes following initiation of the vancomycin infusion, at the end of the infusion, serially at 60, 120, 300, and 480 minutes after the infusion finished, and immediately prior to the next dose. Vancomycin concentration-time profiles at steady state were fit to a noncompartmental model to determine the pharmacokinetic parameters. Vancomycin trough concentration was correlated to AUC0-24 (r = 0.83, P<0.001). Total body weight was a predictor of volume of distribution (r = 0.43, p = 0.03). Age, serum creatinine, and creatinine clearance (CrCl) were found to be predictors for vancomycin clearance (r =-0.67,-0.52, and 0.72, respectively). CrCl was the best predictor of vancomycin CL and addition of other variables to a multivariate model failed to improve model fit. Vancomycin trough concentration may not be an adequate surrogate of AUC0-24. Additional research is needed to determine dosing strategies to optimize AUC0-24 while limiting toxicity.

Study was carried out to investigate microorganisms in urine contaminated soils around lecture theatres within Federal University of Technology, Akure. Fortyeight soil samples were collected and analyzed using soil serial dilution and pour plating techniques. Nutrient Agar was used for bacteria isolation and subculture while Potato dextrose agar and Warcup method were used for fungi isolation. Urine contaminated soil samples were collected from Biology Department Lecture Theatre, University Diploma Lecture Theatre and Microbiology Lecture Theatre. Bacteria isolated from these soils and their prevalence include Bacillus species (31%), Corynebacterium species (24%), Staphylococcus species (17%), Enterobacter cloacae (9%), Micrococcus species (7%), Klebsiella liquefasciens (4%), Flavobacterium rigense (3%), Acinetobacter anitratus (3%), and Alcaligenes eutrophus (2%). The predominant bacteria were Bacilli, and the least was Alcaligenes eutrophus. Fungal isolates were Aspergillus species (46%), Trichoderma viride (15%), Articulospora inflata (11%), Varicosporium elodeae (9%), Rhizopus nigricans (7%), Gliocladium deliquescens (6%), Penicillium notatum (4%) and Beauveria bassiana (2%). Predominant fungi genus in soils from these sites was Aspergillus. Soil from Microbiology Department area generally had the highest counts. In this study, the researchers discussed the public health implications of persistent urination in public soils as potential source of pollution to man and plants.

Bacterial infections caused by antibiotic-resistant pathogens are a significant public health problem. This is because the transmission of infectious diseases is shifting, and new antibiotic-resistant strains of bacteria are emerging. The development of biofilms that are resistant to antibiotics poses another hurdle to drugs and treatment alternatives. Therefore, there is an urgent need to develop innovative strategies to effectively eliminate antibiotic-resistant microorganisms effectively. Natural coumarins have broad spectrum bioactivity and the potential for lower resistance. Coumarin is a secondary metabolite found in certain plants, fungi, and bacteria. It is highly effective against methicillin-resistant Staphylococcus aureus (MRSA). Therefore, coumarin can be used as an alternative to combat MRSA. However, most antibacterial agents lack selective targeting of pathological sites, limiting the efficacy of their antibacterial activity. Efficient MRSA treatments can be achieved ...

Antimicrobial peptides (AMPs) represent promising alternatives to conventional antibiotics in order to defeat multidrug-resistant bacteria such as Streptococcus pneumoniae. In this study, thirteen antimicrobial peptides were designed based on two natural peptides indolicidin and ranalexin. Our results revealed that four hybrid peptides RN7-IN10, RN7-IN9, RN7-IN8, and RN7-IN6 possess potent antibacterial activity against 30 pneumococcal clinical isolates (MIC 7.81-15.62µg/ml). These four hybrid peptides also showed broad spectrum antibacterial activity (7.81µg/ml) against S. aureus, methicillin resistant S. aureus (MRSA), and E. coli. Furthermore, the time killing assay results showed that the hybrid peptides were able to eliminate S. pneumoniae within less than one hour which is faster than the standard drugs erythromycin and ceftriaxone. The cytotoxic effects of peptides were tested against human erythrocytes, WRL-68 normal liver cell line, and NL-20 normal lung cell line. The results revealed that none of the thirteen peptides have cytotoxic or hemolytic effects at their MIC values. The in silico molecular docking study was carried out to investigate the binding properties of peptides with three pneumococcal virulent targets by Autodock Vina. RN7IN6 showed a strong affinity to target proteins; autolysin, pneumolysin, and pneumococcal surface protein A (PspA) based on rigid docking studies. Our results suggest that the hybrid peptides could be suitable candidates for antibacterial drug development.

In an effort to develop new fluoroquinolones, we synthesized eight compounds and tested them against a panel of bacteria. The design of these compounds was guided by the introduction of the isothiazoloquinolone motif. The three most active compounds in this series, 8-10, demonstrated good antibacterial activity against methicillin-sensitive Staphylococcus aureus and healthcare-acquired methicillin-resistant Staphylococcus aureus (MIC 0.62-6.3 µg/mL). Further, when these three active compounds were tested for their inhibitory effects on bacterial enzymes, compound 9 was the most effective agent exhibiting IC50 values of 33.9 and 116.5 μM in the S. aureus deoxyribonucleic acid (DNA) gyrase supercoiling and topoisomerase IV decatenation assays, respectively.