Staphylococcus aureus(S. aureus) is a common pathogenic bacterium in animal husbandry that can cause diseases such as mastitis, skin infections, arthritis, and other ailments. The formation of biofilms threatens and e...Staphylococcus aureus(S. aureus) is a common pathogenic bacterium in animal husbandry that can cause diseases such as mastitis, skin infections, arthritis, and other ailments. The formation of biofilms threatens and exacerbates S. aureus infection by allowing the bacteria to adhere to pathological areas and livestock product surfaces, thus triggering animal health crises and safety issues with livestock products. To solve this problem, in this review, we provide a brief overview of the harm caused by S. aureus and its biofilms on livestock and animal byproducts(meat and dairy products). We also describe the ways in which S. aureus spreads in animals and the threats it poses to the livestock industry. The processes and molecular mechanisms involved in biofilm formation are then explained. Finally, we discuss strategies for the removal and eradication of S. aureus and biofilms in animal husbandry, including the use of antimicrobial peptides, plant extracts, nanoparticles, phages, and antibodies. These strategies to reduce the spread of S. aureus in animal husbandry help maintain livestock health and improve productivity to ensure the ecologically sustainable development of animal husbandry and the safety of livestock products.展开更多
Background:Treatment of methicillin-resistant Staphylococcus aureus(MRSA)biofilm infections in implant placement surgery is limited by the lack of antimicrobial activity of titanium(Ti)implants.There is a need to expl...Background:Treatment of methicillin-resistant Staphylococcus aureus(MRSA)biofilm infections in implant placement surgery is limited by the lack of antimicrobial activity of titanium(Ti)implants.There is a need to explore more effective approaches for the treatment of MRSA biofilm infections.Methods:Herein,an interfacial functionalization strategy is proposed by the integration of mesoporous polydopamine nanoparticles(PDA),nitric oxide(NO)release donor sodium nitroprusside(SNP)and osteogenic growth peptide(OGP)onto Ti implants,denoted as Ti-PDA@SNP-OGP.The physical and chemical properties of Ti-PDA@SNP-OGP were assessed by scanning electron microscopy,X-ray photoelectron spectroscope,water contact angle,photothermal property and NO release behavior.The synergistic antibacterial effect and elimination of the MRSA biofilms were evaluated by 2′,7′-dichlorofluorescein diacetate probe,1-N-phenylnaphthylamine assay,adenosine triphosphate intensity,O-nitrophenyl-β-D-galactopyranoside hydrolysis activity,bicinchoninic acid leakage.Fluorescence staining,assays for alkaline phosphatase activity,collagen secretion and extracellular matrix mineralization,quantitative real‑time reverse transcription‑polymerase chain reaction,and enzyme-linked immunosorbent assay(ELISA)were used to evaluate the inflammatory response and osteogenic ability in bone marrow stromal cells(MSCs),RAW264.7 cells and their co-culture system.Giemsa staining,ELISA,micro-CT,hematoxylin and eosin,Masson's trichrome and immunohistochemistry staining were used to evaluate the eradication of MRSA biofilms,inhibition of inflammatory response,and promotion of osseointegration of Ti-PDA@SNP-OGP in vivo.Results:Ti-PDA@SNP-OGP displayed a synergistic photothermal and NO-dependent antibacterial effect against MRSA following near-infrared light(NIR)irradiation,and effectively eliminated the formed MRSA biofilms by inducing reactive oxygen species(ROS)-mediated oxidative stress,destroying bacterial membrane integrity and causing leakage of intracellular components(P<0.01).In vitro experiments revealed that Ti-PDA@SNP-OGP not only facilitated osteogenic differentiation of MSCs,but also promoted the polarization of pro-inflammatory M1 macrophages to the anti-inflammatory M2-phenotype(P<0.05 or P<0.01).The favorable osteo-immune microenvironment further facilitated osteogenesis of MSCs and the anti-inflammation of RAW264.7 cells via multiple paracrine signaling pathways(P<0.01).In vivo evaluation confirmed the aforementioned results and revealed that Ti-PDA@SNP-OGP induced ameliorative osseointegration in an MRSA-infected femoral defect implantation model(P<0.01).Conclusions:Ti-PDA@SNP-OGP is a promising multi-functional material for the high-efficient treatment of MRSA infections in implant replacement surgeries.展开更多
Slightly acidic electrolyzed water(SAEW)has proven to be an efficient and novel sanitizer in food and agriculture field.This study assessed the efficacy of SAEW(30 mg/L)at 40℃on the inactivation of foodbome pathogens...Slightly acidic electrolyzed water(SAEW)has proven to be an efficient and novel sanitizer in food and agriculture field.This study assessed the efficacy of SAEW(30 mg/L)at 40℃on the inactivation of foodbome pathogens and detachment of multi-resistant Staphylococcus aureus(MRSA)biofilm.Furthermore.the underlying mechanism of MRS A biofilm under heated SAEW at 40℃treatment on metabolic profiles was investigated.The results showed that the heated SAEW at 40℃significantly effectively against foodbome pathogens of 1.96-7.56(lg(CFU/g))reduction in pork,chicken,spinach,and lettuce.The heated SAEW at 40℃treatment significantly reduced MRS A biofilm cells by 2.41(lg(CFU/cm^(2))).The synergistic effect of SAEW treatment showed intense anti-biofilm activity in decreasing cell density and impairing biofilm cell membranes.Global metabolic response of MRSA biofilms,treated by SAEW at 40℃,revealed the alterations of intracellular metabolites,including amino acids,organic acid,fatty acid,and lipid.Moreover,signaling pathways involved in amino acid metabolism,energy metabolism,nucleotide synthesis,carbohydrate metabolites,and lipid biosynthesis were functionally disrupted by the SAEW at 40℃treatment.As per our knowledge,this is the first research to uncover the potential mechanism of heated SAEW treatment against MRSA biofilm on food contact surface.展开更多
Staphylococcus aureus is a serious foodborne pathogen threatening food safety and public health.Especially the emergence of methicillin-resistant Staphylococcus aureus(MRSA)increased the difficulty of S.aureus treatme...Staphylococcus aureus is a serious foodborne pathogen threatening food safety and public health.Especially the emergence of methicillin-resistant Staphylococcus aureus(MRSA)increased the difficulty of S.aureus treatment.Staphyloxanthin is a crucial virulence factor of S.aureus.Blocking staphyloxanthin production could help the host immune system counteract the invading S.aureus cells.In this study,we first screened for staphyloxanthin inhibitors using a virtual screening method.The outcome of the virtual screening method resulted in the identification of eugenol(300μg/mL),which significantly inhibits the staphyloxanthin production in S.aureus ATCC 29213,S.aureus Newman,MRSA ATCC 43300 and MRSA ATCC BAA1717by 84.2%,63.5%,68.1%,and 79.5%,respectively.The outcome of the growth curve assay,field-emission scanning electron,and confocal laser scanning microscopy analyses confirmed that eugenol at the test concentration did not affect the morphology and growth of S.aureus.Moreover,the survival rate of S.aureus ATCC 29213 and MRSA ATCC 43300 under H_(2)O_(2) pressure decreased to 51.9%and 45.5%in the presence of eugenol,respectively.The quantitative RT-PCR and molecular simulation studies revealed that eugenol targets staphyloxanthin biosynthesis by downregulating the transcription of the crtM gene and inhibiting the activity of the CrtM enzyme.Taken together,we first determined that eugenol was a prominent compound for staphyloxanthin inhibitor to combat S.aureus especially MRSA infections.展开更多
Sensitive detection of Staphylococcus aureus enterotoxin B(SEB)is of importance for preventing food poisoning from threatening human health.In this work,an electrochemical and colorimetric dual-signal detection assay ...Sensitive detection of Staphylococcus aureus enterotoxin B(SEB)is of importance for preventing food poisoning from threatening human health.In this work,an electrochemical and colorimetric dual-signal detection assay of SEB was developed.The probe(Ab2/AuPt@Fe-N-C)was bound to SEB captured by Ab1,where the Ab2/AuPt@Fe-N-C triggered methylene blue degradation and resulted in the decrease of electrochemical signal.Furthermore,the probe catalyzed the oxidation of 3,3’,5,5’-tetramethyl biphenyl to generate a colorimetric absorbance at 652 nm.Once the target was captured and formed a sandwich-like complex,the color changed from colorless to blue.SEB detection by colorimetric and electrochemical methods showed a linear relationship in the concentration ranges of 0.0002-10.0000 and 0.0005-10.0000 ng/mL,with limits of detection of 0.0667 and 0.1670 pg/mL,respectively.The dual-signal biosensor was successfully used to detect SEB in milk and water samples,which has great potential in toxin detection in food and the environment.展开更多
Objective:To determine the antibiotic resistance profile(ARP)of Staphylococcus(S.)aureus isolates and molecular typing of the methicillin-resistant S.aureus(MRSA)isolates from Tuanku Mizan Armed Forces Hospital(TMAFH)...Objective:To determine the antibiotic resistance profile(ARP)of Staphylococcus(S.)aureus isolates and molecular typing of the methicillin-resistant S.aureus(MRSA)isolates from Tuanku Mizan Armed Forces Hospital(TMAFH),Kuala Lumpur.Methods:The ARP and presence of the pvl gene were determined for 209 S.aureus isolates from clinical specimens.Of these,123 were methicillin-susceptible S.aureus(MSSA)isolates and 86 were MRSA isolates.All MRSA isolates were characterized using SCCmec typing and spa typing.Descriptive analysis was performed to compare the demographic data with the phenotypic and genotypic variables of the S.aureus isolates.Results:No vancomycin-intermediate and-resistant S.aureus(VISA and VRSA,respectively)were detected among the study isolates.The MSSA isolates showed low resistance rates to all tested antibiotics,were commonly invasive(28/42,66.7%),and mostly harboured pvl(35/42,83.3%).Meanwhile,MRSA isolates showed high resistance to penicillin(86/86,100%),ampicillin(86/86,100%),sulbactam/ampicillin(86/86,100%),cefuroxime(81/86,94.19%),cefoperazone(76/86,88.37%),azithromycin(56/86,65.12%),and erythromycin(54/86,62.79%).The majority of MRSA isolates were of SCCmec type IVh(65/86,75.58%),spa type t032(55/85,63.95%),and grouped into spaCC-t022(66/85,77.65%).The t032 type was found to be associated with resistance traits to azithromycin and erythromycin(P<0.05).We also found several spa types that are typically associated with hospital-,community-,and livestock-associated MRSA co-existing in our MRSA population.Conclusions:This study reflected the consistent absence of VISA and VRSA and corroborated the clonal shifting of MRSA isolates in the Malaysian MRSA isolates.展开更多
Persistent methicillin-sensitive staphylococcus aureus(MSSA)bacteremia is usually defined as persistent bacteremia despite 7 days of appropriate antibiotic therapy.While nafcillin,cefazolin,or oxacillin are excellent ...Persistent methicillin-sensitive staphylococcus aureus(MSSA)bacteremia is usually defined as persistent bacteremia despite 7 days of appropriate antibiotic therapy.While nafcillin,cefazolin,or oxacillin are excellent antimicrobial options,persistent MSSA is a commonly encountered phenomenon in clinical practice for which further guidelines on appropriate management are necessitated.Here we highlight two cases of MSSA bacteremia requiring salvage therapy with ertapenem.展开更多
Objective:To describe clinical and epidemiological characteristics,antimicrobial susceptibility and mortality-associated factors of healthcare-associated infections(HCAIs)caused by Staphylococcus(S.)aureus in children...Objective:To describe clinical and epidemiological characteristics,antimicrobial susceptibility and mortality-associated factors of healthcare-associated infections(HCAIs)caused by Staphylococcus(S.)aureus in children.Methods:We conducted a retrospective,single-centre study of pediatric HCAIs caused by S.aureus from a tertiary care hospital in Turkey between February 2014 and December 2019.The clinical and epidemiological characteristics and antimicrobial susceptibility of the methicillin-susceptible and methicillin-resistant S.aureus(MSSA and MRSA)isolates was evaluated.Results:A total of 310 pediatric patients were examined.Overall,225(72.6%)isolates were MSSA and 85(27.4%)were MRSA.All S.aureus isolates were susceptible to teicoplanin,vancomycin,linezolid,tigecycline,mupirocin,and daptomycin.Penicillin resistance rates were high(89.0%),while fosfomycin,gentamicin,and clindamycin resistance rates were low(1.3%,1.0%,and 2.3%,respectively).Except susceptibility to fosfomycin,which was significantly lower in 2014 compared to 2018 and 2019,no significant difference was found in the antimicrobial susceptibility of S.aureus isolates between the years.Baseline characteristics and mortality rate were similar comparing MRSA and MSSA causing HCAIs.The mortality rate of HCAIs caused by S.aureus was 6.5%(20 patients).Malignancy was an independent risk factor associated with mortality in the multivariate analysis(OR 5.446,95%CI 1.573-18.849).Conclusions:Our findings demonstrate that MSSA remained the most causative agent of HCAIs caused by S.aureus.The mortality rate was 6.5%,the antibiotic resistance rate was quite high for penicillin and diagnosis of malignancy was the main risk factor for increasing mortality in children.These findings could help improve the management of HCAIs caused by S.aureus in children.展开更多
Host-directed therapy(HDT)is an emerging novel approach for treating multidrug-resistant Staphylococcus aureus(S.aureus)infection.Functioning as the indispensable specific cellular receptor for a-toxin(Hla),a-disinteg...Host-directed therapy(HDT)is an emerging novel approach for treating multidrug-resistant Staphylococcus aureus(S.aureus)infection.Functioning as the indispensable specific cellular receptor for a-toxin(Hla),a-disintegrin and metalloproteinase 10(ADAM10)is exploited to accelerate S.aureus infection through diverse mechanisms.The extraordinary contribution of ADAM10 to S.aureus pathogenesis renders it an attractive HDT target for combating S.aureus infection.Our study is the first to demonstrate the indispensable role of ADAM10 in S.aureus-induced necroptosis,and it enhances our knowledge of the role of ADAM10 in S.aureus infection.Using a fluorogenic substrate assay,we further identified kaempferol as a potent ADAM10 inhibitor that effectively protected mice from S.aureus infection by suppressing Hla-mediated barrier disruption and necroptosis.Collectively,our work presents a novel hostdirected therapeutic strategy for using the promising candidate kaempferol to treat S.aureus infection and other diseases relevant to the disordered upregulation of ADAM10.展开更多
Background:Staphylococcus aureus can cause serious infections by secreting many superantigen exotoxins in“carrier”or“pathogenic”states.HLA DQ and HLA DR humanized mice have been used as a small animal model to stu...Background:Staphylococcus aureus can cause serious infections by secreting many superantigen exotoxins in“carrier”or“pathogenic”states.HLA DQ and HLA DR humanized mice have been used as a small animal model to study the role of two molecules during S.aureus infection.However,the contribution of HLA DP to S.aureus infection is unknown yet.Methods:In this study,we have produced HLA DP401 and HLA DRA0101 humanized mice by microinjection of C57BL/6J zygotes.Neo-floxed IAβ+/-mice were crossbred with Ella-Cre and further crossbred with HLA DP401 or HLA-DRA0101 humanized mice.After several rounds of traditional crossbreeding,we finally obtained HLA DP401-IAβ-/-and HLA DRA-IAβ-/-humanized mice,in which human DP401 or DRA0101 molecule was introduced into IAβ-/-mice deficient in endogenous murine MHC classⅡmolecules.A transnasal infection murine model of S.aureus pneumonia was induced in the humanized mice by administering 2×108CFU of S.aureus Newman dropwise into the nasal cavity.The immune responses and histopathology changes were further assessed in lungs in these infected mice.Results:We evaluated the local and systemic effects of S.aureus delivered intranasally in HLA DP401-IAβ-/-and HLA DRA-IAβ-/-transgenic mice.S.aureus Newman infection significantly increased the m RNA level of IL 12p40 in lungs in humanized mice.An increase in IFN-γand IL-6 protein was observed in HLA DRA-IAβ-/-mice.We observed a declining trend in the percentage of F4/80+macrophages in lungs in HLA DP401-IAβ-/-mice and a decreasing ratio of CD4+to CD8+T cells in lungs in IAβ-/-mice and HLA DP401-IAβ-/-mice.A decreasing ratio of Vβ3+to Vβ8+T cells was also found in the lymph node of IAβ-/-mice and HLA DP401-IAβ-/-mice.S.aureus Newman infection resulted in a weaker pathological injury in lungs in IAβ-/-genetic background mice.Conclusion:These humanized mice will be an invaluable mouse model to resolve the pathological mechanism of S.aureus pneumonia and study what role DP molecule plays in S.aureus infection.展开更多
BACKGROUND Staphylococcus caprae(S.caprae)is a human commensal bacterium which can be detected in the nose,nails,and skin.It can be responsible for heterogeneous infections such as bacteremia,endocarditis,pneumonia,ac...BACKGROUND Staphylococcus caprae(S.caprae)is a human commensal bacterium which can be detected in the nose,nails,and skin.It can be responsible for heterogeneous infections such as bacteremia,endocarditis,pneumonia,acute otitis externa,peritonitis,and urinary tract infections.Bone and joint infections due to S.caprae have also been reported,but most of them resulted from the infection of orthopedic devices,especially joint prostheses and internal osteosynthesis devices.Rare cases of primary osteoarticular infections caused by S.caprae have been described,including osteitis,arthritis,or spondylodiscitis.CASE SUMMARY We report an unusual case of subacute osteomyelitis in a toe phalanx caused by S.caprae in a 14.5-year-old girl.CONCLUSION Subacute S.caprae osteomyelitis is a little-known and probably underestimated community-acquired infectious disease.This microorganism’s pathogenicity should be seen as more than a classic nosocomial orthopedic device infection.展开更多
A retrospective analysis of the diagnostic laboratory submissions from 2016 to 2020 was performed to assess the antibiotic resistance of Staphylococcus pseudintermedius and determine locations in the hospital which mi...A retrospective analysis of the diagnostic laboratory submissions from 2016 to 2020 was performed to assess the antibiotic resistance of Staphylococcus pseudintermedius and determine locations in the hospital which might be acting as environmental source(s). Previous studies have identified a significant increase in infections with S. pseudintermedius. Samples were taken from the hospital environment by swabbing areas in the intensive care unit and anesthesia preparation room and bacterial species identified. Isolates obtained from patients were then examined regarding the ability to form biofilm, an important phenotype on hospital-related infection. In addition, veterinary hospital associated strains of S. pseudintermedius were used to determine the bactericidal effect of the used disinfectant, applying the hospital current protocol, by comparing the efficacy against S. pseudintermediius and a strain of Staphylococcus aureus from a dog. The isolates identified were resistant to commonly used antibiotics such as enrofloxacin and cephalosporins, and 45% percent of those were methicillin resistant. The environmental survey in the hospital identified S. pseudintermedius in the pre-anesthesia area, although the isolate was killed by the current used disinfection protocol. A few disease associated bacteria were evaluated for biofilm formation in comparison to a dog isolate of Staphylococcus aureus, demonstrating strong ability to form biofilms.展开更多
BACKGROUND Although neonatal Staphylococcus aureus pneumonia is common and usually curable,it can also be refractory and life-threatening.Herein,we report a case of severe neonatal community-acquired methicillin-resis...BACKGROUND Although neonatal Staphylococcus aureus pneumonia is common and usually curable,it can also be refractory and life-threatening.Herein,we report a case of severe neonatal community-acquired methicillin-resistant Staphylococcus aureus(CA-MRSA)necrotizing pneumonia with bilateral recurrent pyopneumothorax,respiratory failure,heart failure,and cardiac arrest.We hope our report will add to the understanding of this disease.CASE SUMMARY An 18-d-old boy presented with cough for five days,fever for three days,and dyspnea for two days.Preadmission chest radiograph revealed high-density shadows in both lungs.On admission,his oxygen saturation fluctuated around 90%under synchronized intermittent mandatory ventilation.He was unconscious,with dyspnea,weak heart sounds and hepatomegaly.Moist crackles were present throughout his left lung,while the breath sounds in the right lung were decreased.After high-frequency oscillatory ventilation,empiric antimicrobials(meropenem and vancomycin),improved circulation,and right pleural cavity drainage for right pneumothorax(approximately 90%compression),his oxygen saturation level stayed above 95%,and recruitment of the right lung was observed.His condition did not deteriorate until the 5th day of hospitalization(DOH 5).On the morning of DOH 5,his oxygen saturation decreased.Subsequent chest radiograph showed bilateral pneumothorax with nearly 100%compression of the left lung.Desaturation was not relieved after urgent left pleural cavity drainage,and cardiac arrest occurred soon thereafter.Although his spontaneous heartbeat returned through emergency resuscitation and salvage antibacterial therapy(linezolid and levofloxacin)was administered given the detection and antimicrobial susceptibility of MRSA,he showed no improvement,with recurrent pyopneumothorax and continued drainage of purulent fluid and necrotic lung tissue fragments from the pleural cavity.Eventually,his parents refused extracorporeal membrane oxygenation(ECMO)and gave up all the treatments,and the newborn passed away soon after withdrawal on DOH 13.CONCLUSION Neonatal MRSA pneumonia can be refractory and lethal,especially in cases where necrotizing pneumonia leads to extensive lung necrosis and recurrent pneumothorax.Despite treatment with linezolid and other medical measures,it may still be ineffective.Currently,ECMO has been a remedial therapy,but if the lung tissue is too severely eroded to be repaired,it may be useless unless the infection can be controlled and lung transplantation can be performed.Regardless of whether ECMO is initiated,the key to successful treatment is to achieve control over the pneumonia caused by MRSA as soon as possible and to reverse lung injury as much as possible.展开更多
The coagulase-negative staphylococci (CoNS) group was considered saprophytic or rarely pathogenic for many years. Since the first case of septicemia caused by CoNS, there has been a progressive increase in the prevale...The coagulase-negative staphylococci (CoNS) group was considered saprophytic or rarely pathogenic for many years. Since the first case of septicemia caused by CoNS, there has been a progressive increase in the prevalence of healthcare-associated infections caused by CoNS. The CoNS group has emerged as one of the main causes of nosocomial infections related to vascular catheters and prostheses, especially among immunocompromised patients. This gradual increase in infections is due to the change in the relationship between patients and procedures since CoNS are closely related to devices implanted in the human body. CoNS are successful in colonizing the host because they have several virulence mechanisms, such as biofilm formation and production of enzymes and toxins, in addition to several mechanisms of resistance to antimicrobials. Despite their great clinical relevance, few studies have focused on CoNS’s pathogenicity and resistance to antimicrobials, which reveals the current need to better understand the factors by which this group became pathogenic to humans and other animals. This review aims to synthesize the aspects related to the pathogenicity and antimicrobial resistance in CoNS.展开更多
[Objectives]To observe the effects of daphnetin on mastitis induced by Staphylococcus aureus in mice.[Methods]18 postpartum ICR female mice were used to establish mastitis animal model,and were randomly divided into t...[Objectives]To observe the effects of daphnetin on mastitis induced by Staphylococcus aureus in mice.[Methods]18 postpartum ICR female mice were used to establish mastitis animal model,and were randomly divided into three groups(A,B,and C)with 6 mice in each group.Group A:blank control group;group B:S.Aureus model group;group C:S.Aureus model+daphnetin group.The experimental groups were injected 1 mL of 1.0×104 CFU/100μL of S.aureus of along the nipple catheter.The suspension was placed in the 3 rd and 4 th pairs of mammary glands,and the control group was injected with the same dose of normal saline.On the second day after infection,the rats in group A,B and C were given drugs by gavage,while the rats in group A and B were given normal saline and the rats in group C were given daphnetin once a day for 6 consecutive days.Blood samples were collected from living eyeballs,and blood cells were analyzed by automatic flow cytometer after anticoagulation.[Results]The NLR and Systemie Immune Inflammati-on Index(SII)in the blood of mastitis mice induced by S.aureus were significantly higher than those in the control group(P<0.01),suggesting that neutrophil to lymphocyte ratio(NLR)and SII can be used as diagnostic indicators of mastitis,and the levels of NLR and SII decreased significantly after daphnetin intervention.[Conclusions]NLR and SII showed high levels in mastitis mice,which are valuable for the diagnosis of mastitis and the evaluation of its prognosis.After the intervention of daphnetin,both of them decreased significantly,indicating that daphnetin has a good prognosis trend in mastitis mice induced by S.aureus.展开更多
基金supported by the National Natural Science Foundation of China (31930106 and U22A20514, U23A20232)the National Key R&D Program of China (2022YFD1300404)+2 种基金the 2115 Talent Development Program of China Agricultural University (1041-00109019)the Pinduoduo-China Agricultural University Research Fund (PC2023A01001)the Special Fund for Henan Agriculture Research System (HARS-2213-Z1)。
文摘Staphylococcus aureus(S. aureus) is a common pathogenic bacterium in animal husbandry that can cause diseases such as mastitis, skin infections, arthritis, and other ailments. The formation of biofilms threatens and exacerbates S. aureus infection by allowing the bacteria to adhere to pathological areas and livestock product surfaces, thus triggering animal health crises and safety issues with livestock products. To solve this problem, in this review, we provide a brief overview of the harm caused by S. aureus and its biofilms on livestock and animal byproducts(meat and dairy products). We also describe the ways in which S. aureus spreads in animals and the threats it poses to the livestock industry. The processes and molecular mechanisms involved in biofilm formation are then explained. Finally, we discuss strategies for the removal and eradication of S. aureus and biofilms in animal husbandry, including the use of antimicrobial peptides, plant extracts, nanoparticles, phages, and antibodies. These strategies to reduce the spread of S. aureus in animal husbandry help maintain livestock health and improve productivity to ensure the ecologically sustainable development of animal husbandry and the safety of livestock products.
基金financially supported by the National Natural Science Foundation of China(82101069,82102537,82160411,82002278)the Natural Science Foundation of Chongqing Science and Technology Commission(CSTC2021JCYJ-MSXMX0170,CSTB2022BSXM-JCX0039)+2 种基金the First Affiliated Hospital of Chongqing Medical University Cultivating Fund(PYJJ2021-02)the Beijing Municipal Science&Technology Commission(Z221100007422130)the Youth Incubation Program of Medical Science and Technology of PLA(21QNPY116).
文摘Background:Treatment of methicillin-resistant Staphylococcus aureus(MRSA)biofilm infections in implant placement surgery is limited by the lack of antimicrobial activity of titanium(Ti)implants.There is a need to explore more effective approaches for the treatment of MRSA biofilm infections.Methods:Herein,an interfacial functionalization strategy is proposed by the integration of mesoporous polydopamine nanoparticles(PDA),nitric oxide(NO)release donor sodium nitroprusside(SNP)and osteogenic growth peptide(OGP)onto Ti implants,denoted as Ti-PDA@SNP-OGP.The physical and chemical properties of Ti-PDA@SNP-OGP were assessed by scanning electron microscopy,X-ray photoelectron spectroscope,water contact angle,photothermal property and NO release behavior.The synergistic antibacterial effect and elimination of the MRSA biofilms were evaluated by 2′,7′-dichlorofluorescein diacetate probe,1-N-phenylnaphthylamine assay,adenosine triphosphate intensity,O-nitrophenyl-β-D-galactopyranoside hydrolysis activity,bicinchoninic acid leakage.Fluorescence staining,assays for alkaline phosphatase activity,collagen secretion and extracellular matrix mineralization,quantitative real‑time reverse transcription‑polymerase chain reaction,and enzyme-linked immunosorbent assay(ELISA)were used to evaluate the inflammatory response and osteogenic ability in bone marrow stromal cells(MSCs),RAW264.7 cells and their co-culture system.Giemsa staining,ELISA,micro-CT,hematoxylin and eosin,Masson's trichrome and immunohistochemistry staining were used to evaluate the eradication of MRSA biofilms,inhibition of inflammatory response,and promotion of osseointegration of Ti-PDA@SNP-OGP in vivo.Results:Ti-PDA@SNP-OGP displayed a synergistic photothermal and NO-dependent antibacterial effect against MRSA following near-infrared light(NIR)irradiation,and effectively eliminated the formed MRSA biofilms by inducing reactive oxygen species(ROS)-mediated oxidative stress,destroying bacterial membrane integrity and causing leakage of intracellular components(P<0.01).In vitro experiments revealed that Ti-PDA@SNP-OGP not only facilitated osteogenic differentiation of MSCs,but also promoted the polarization of pro-inflammatory M1 macrophages to the anti-inflammatory M2-phenotype(P<0.05 or P<0.01).The favorable osteo-immune microenvironment further facilitated osteogenesis of MSCs and the anti-inflammation of RAW264.7 cells via multiple paracrine signaling pathways(P<0.01).In vivo evaluation confirmed the aforementioned results and revealed that Ti-PDA@SNP-OGP induced ameliorative osseointegration in an MRSA-infected femoral defect implantation model(P<0.01).Conclusions:Ti-PDA@SNP-OGP is a promising multi-functional material for the high-efficient treatment of MRSA infections in implant replacement surgeries.
基金supported by Brain Korea (BK)21 Plus Project (4299990913942)funded by the Korean Government,Koreathe Collabo Project funded by the Ministry of SMEs and Startups (C1016120-01-02)the National Research Foundation of Korea (NRF) (2018007551)。
文摘Slightly acidic electrolyzed water(SAEW)has proven to be an efficient and novel sanitizer in food and agriculture field.This study assessed the efficacy of SAEW(30 mg/L)at 40℃on the inactivation of foodbome pathogens and detachment of multi-resistant Staphylococcus aureus(MRSA)biofilm.Furthermore.the underlying mechanism of MRS A biofilm under heated SAEW at 40℃treatment on metabolic profiles was investigated.The results showed that the heated SAEW at 40℃significantly effectively against foodbome pathogens of 1.96-7.56(lg(CFU/g))reduction in pork,chicken,spinach,and lettuce.The heated SAEW at 40℃treatment significantly reduced MRS A biofilm cells by 2.41(lg(CFU/cm^(2))).The synergistic effect of SAEW treatment showed intense anti-biofilm activity in decreasing cell density and impairing biofilm cell membranes.Global metabolic response of MRSA biofilms,treated by SAEW at 40℃,revealed the alterations of intracellular metabolites,including amino acids,organic acid,fatty acid,and lipid.Moreover,signaling pathways involved in amino acid metabolism,energy metabolism,nucleotide synthesis,carbohydrate metabolites,and lipid biosynthesis were functionally disrupted by the SAEW at 40℃treatment.As per our knowledge,this is the first research to uncover the potential mechanism of heated SAEW treatment against MRSA biofilm on food contact surface.
基金supported by the National Natural Science Foundation of China (31972169 and 32001798)。
文摘Staphylococcus aureus is a serious foodborne pathogen threatening food safety and public health.Especially the emergence of methicillin-resistant Staphylococcus aureus(MRSA)increased the difficulty of S.aureus treatment.Staphyloxanthin is a crucial virulence factor of S.aureus.Blocking staphyloxanthin production could help the host immune system counteract the invading S.aureus cells.In this study,we first screened for staphyloxanthin inhibitors using a virtual screening method.The outcome of the virtual screening method resulted in the identification of eugenol(300μg/mL),which significantly inhibits the staphyloxanthin production in S.aureus ATCC 29213,S.aureus Newman,MRSA ATCC 43300 and MRSA ATCC BAA1717by 84.2%,63.5%,68.1%,and 79.5%,respectively.The outcome of the growth curve assay,field-emission scanning electron,and confocal laser scanning microscopy analyses confirmed that eugenol at the test concentration did not affect the morphology and growth of S.aureus.Moreover,the survival rate of S.aureus ATCC 29213 and MRSA ATCC 43300 under H_(2)O_(2) pressure decreased to 51.9%and 45.5%in the presence of eugenol,respectively.The quantitative RT-PCR and molecular simulation studies revealed that eugenol targets staphyloxanthin biosynthesis by downregulating the transcription of the crtM gene and inhibiting the activity of the CrtM enzyme.Taken together,we first determined that eugenol was a prominent compound for staphyloxanthin inhibitor to combat S.aureus especially MRSA infections.
基金This work was financially supported by Major Science and Technology Project of Yunnan Province(202302AE090022)Key Research and Development Program of Yunnan(202203AC100010)+4 种基金the National Natural Science Foundation of China(32160597,32160236,32371463)National Key Research and Development Program of China(2022YFC2601604)Cardiovascular Ultrasound Innovation Team of Yunnan Province(202305AS350021)Spring City Plan:the High-level Talent Promotion and Training Project of Kunming(2022SCP001)the second phase of“Double-First Class”Program Construction of Yunnan University.
文摘Sensitive detection of Staphylococcus aureus enterotoxin B(SEB)is of importance for preventing food poisoning from threatening human health.In this work,an electrochemical and colorimetric dual-signal detection assay of SEB was developed.The probe(Ab2/AuPt@Fe-N-C)was bound to SEB captured by Ab1,where the Ab2/AuPt@Fe-N-C triggered methylene blue degradation and resulted in the decrease of electrochemical signal.Furthermore,the probe catalyzed the oxidation of 3,3’,5,5’-tetramethyl biphenyl to generate a colorimetric absorbance at 652 nm.Once the target was captured and formed a sandwich-like complex,the color changed from colorless to blue.SEB detection by colorimetric and electrochemical methods showed a linear relationship in the concentration ranges of 0.0002-10.0000 and 0.0005-10.0000 ng/mL,with limits of detection of 0.0667 and 0.1670 pg/mL,respectively.The dual-signal biosensor was successfully used to detect SEB in milk and water samples,which has great potential in toxin detection in food and the environment.
基金The study was funded by the UPNM Short Term Grant (UPNM/2019/GPJP/SP/1).
文摘Objective:To determine the antibiotic resistance profile(ARP)of Staphylococcus(S.)aureus isolates and molecular typing of the methicillin-resistant S.aureus(MRSA)isolates from Tuanku Mizan Armed Forces Hospital(TMAFH),Kuala Lumpur.Methods:The ARP and presence of the pvl gene were determined for 209 S.aureus isolates from clinical specimens.Of these,123 were methicillin-susceptible S.aureus(MSSA)isolates and 86 were MRSA isolates.All MRSA isolates were characterized using SCCmec typing and spa typing.Descriptive analysis was performed to compare the demographic data with the phenotypic and genotypic variables of the S.aureus isolates.Results:No vancomycin-intermediate and-resistant S.aureus(VISA and VRSA,respectively)were detected among the study isolates.The MSSA isolates showed low resistance rates to all tested antibiotics,were commonly invasive(28/42,66.7%),and mostly harboured pvl(35/42,83.3%).Meanwhile,MRSA isolates showed high resistance to penicillin(86/86,100%),ampicillin(86/86,100%),sulbactam/ampicillin(86/86,100%),cefuroxime(81/86,94.19%),cefoperazone(76/86,88.37%),azithromycin(56/86,65.12%),and erythromycin(54/86,62.79%).The majority of MRSA isolates were of SCCmec type IVh(65/86,75.58%),spa type t032(55/85,63.95%),and grouped into spaCC-t022(66/85,77.65%).The t032 type was found to be associated with resistance traits to azithromycin and erythromycin(P<0.05).We also found several spa types that are typically associated with hospital-,community-,and livestock-associated MRSA co-existing in our MRSA population.Conclusions:This study reflected the consistent absence of VISA and VRSA and corroborated the clonal shifting of MRSA isolates in the Malaysian MRSA isolates.
文摘Persistent methicillin-sensitive staphylococcus aureus(MSSA)bacteremia is usually defined as persistent bacteremia despite 7 days of appropriate antibiotic therapy.While nafcillin,cefazolin,or oxacillin are excellent antimicrobial options,persistent MSSA is a commonly encountered phenomenon in clinical practice for which further guidelines on appropriate management are necessitated.Here we highlight two cases of MSSA bacteremia requiring salvage therapy with ertapenem.
文摘Objective:To describe clinical and epidemiological characteristics,antimicrobial susceptibility and mortality-associated factors of healthcare-associated infections(HCAIs)caused by Staphylococcus(S.)aureus in children.Methods:We conducted a retrospective,single-centre study of pediatric HCAIs caused by S.aureus from a tertiary care hospital in Turkey between February 2014 and December 2019.The clinical and epidemiological characteristics and antimicrobial susceptibility of the methicillin-susceptible and methicillin-resistant S.aureus(MSSA and MRSA)isolates was evaluated.Results:A total of 310 pediatric patients were examined.Overall,225(72.6%)isolates were MSSA and 85(27.4%)were MRSA.All S.aureus isolates were susceptible to teicoplanin,vancomycin,linezolid,tigecycline,mupirocin,and daptomycin.Penicillin resistance rates were high(89.0%),while fosfomycin,gentamicin,and clindamycin resistance rates were low(1.3%,1.0%,and 2.3%,respectively).Except susceptibility to fosfomycin,which was significantly lower in 2014 compared to 2018 and 2019,no significant difference was found in the antimicrobial susceptibility of S.aureus isolates between the years.Baseline characteristics and mortality rate were similar comparing MRSA and MSSA causing HCAIs.The mortality rate of HCAIs caused by S.aureus was 6.5%(20 patients).Malignancy was an independent risk factor associated with mortality in the multivariate analysis(OR 5.446,95%CI 1.573-18.849).Conclusions:Our findings demonstrate that MSSA remained the most causative agent of HCAIs caused by S.aureus.The mortality rate was 6.5%,the antibiotic resistance rate was quite high for penicillin and diagnosis of malignancy was the main risk factor for increasing mortality in children.These findings could help improve the management of HCAIs caused by S.aureus in children.
基金supported by the National Natural Science Foundation of China(U22A20523,32172912,and 32102722)the Interdisciplinary Integration and Innovation Project of Jilin University(JLUXKJC2021QZ04)。
文摘Host-directed therapy(HDT)is an emerging novel approach for treating multidrug-resistant Staphylococcus aureus(S.aureus)infection.Functioning as the indispensable specific cellular receptor for a-toxin(Hla),a-disintegrin and metalloproteinase 10(ADAM10)is exploited to accelerate S.aureus infection through diverse mechanisms.The extraordinary contribution of ADAM10 to S.aureus pathogenesis renders it an attractive HDT target for combating S.aureus infection.Our study is the first to demonstrate the indispensable role of ADAM10 in S.aureus-induced necroptosis,and it enhances our knowledge of the role of ADAM10 in S.aureus infection.Using a fluorogenic substrate assay,we further identified kaempferol as a potent ADAM10 inhibitor that effectively protected mice from S.aureus infection by suppressing Hla-mediated barrier disruption and necroptosis.Collectively,our work presents a novel hostdirected therapeutic strategy for using the promising candidate kaempferol to treat S.aureus infection and other diseases relevant to the disordered upregulation of ADAM10.
基金National Science and Technology Major Project,Grant/Award Number:2016YFD0500208,2017ZX10304402-001-012 and 2017ZX10304402-001-006Shanghai Science and Technology Commission“R&D public service platform and institutional capacity improvement project”,Grant/Award Number:21DZ2291300Shanghai Public Health Clinical Center projects,Grant/Award Number:KY-GW-2021-39,KY-GW-2019-19 and KY-GW-2019-11。
文摘Background:Staphylococcus aureus can cause serious infections by secreting many superantigen exotoxins in“carrier”or“pathogenic”states.HLA DQ and HLA DR humanized mice have been used as a small animal model to study the role of two molecules during S.aureus infection.However,the contribution of HLA DP to S.aureus infection is unknown yet.Methods:In this study,we have produced HLA DP401 and HLA DRA0101 humanized mice by microinjection of C57BL/6J zygotes.Neo-floxed IAβ+/-mice were crossbred with Ella-Cre and further crossbred with HLA DP401 or HLA-DRA0101 humanized mice.After several rounds of traditional crossbreeding,we finally obtained HLA DP401-IAβ-/-and HLA DRA-IAβ-/-humanized mice,in which human DP401 or DRA0101 molecule was introduced into IAβ-/-mice deficient in endogenous murine MHC classⅡmolecules.A transnasal infection murine model of S.aureus pneumonia was induced in the humanized mice by administering 2×108CFU of S.aureus Newman dropwise into the nasal cavity.The immune responses and histopathology changes were further assessed in lungs in these infected mice.Results:We evaluated the local and systemic effects of S.aureus delivered intranasally in HLA DP401-IAβ-/-and HLA DRA-IAβ-/-transgenic mice.S.aureus Newman infection significantly increased the m RNA level of IL 12p40 in lungs in humanized mice.An increase in IFN-γand IL-6 protein was observed in HLA DRA-IAβ-/-mice.We observed a declining trend in the percentage of F4/80+macrophages in lungs in HLA DP401-IAβ-/-mice and a decreasing ratio of CD4+to CD8+T cells in lungs in IAβ-/-mice and HLA DP401-IAβ-/-mice.A decreasing ratio of Vβ3+to Vβ8+T cells was also found in the lymph node of IAβ-/-mice and HLA DP401-IAβ-/-mice.S.aureus Newman infection resulted in a weaker pathological injury in lungs in IAβ-/-genetic background mice.Conclusion:These humanized mice will be an invaluable mouse model to resolve the pathological mechanism of S.aureus pneumonia and study what role DP molecule plays in S.aureus infection.
文摘BACKGROUND Staphylococcus caprae(S.caprae)is a human commensal bacterium which can be detected in the nose,nails,and skin.It can be responsible for heterogeneous infections such as bacteremia,endocarditis,pneumonia,acute otitis externa,peritonitis,and urinary tract infections.Bone and joint infections due to S.caprae have also been reported,but most of them resulted from the infection of orthopedic devices,especially joint prostheses and internal osteosynthesis devices.Rare cases of primary osteoarticular infections caused by S.caprae have been described,including osteitis,arthritis,or spondylodiscitis.CASE SUMMARY We report an unusual case of subacute osteomyelitis in a toe phalanx caused by S.caprae in a 14.5-year-old girl.CONCLUSION Subacute S.caprae osteomyelitis is a little-known and probably underestimated community-acquired infectious disease.This microorganism’s pathogenicity should be seen as more than a classic nosocomial orthopedic device infection.
文摘A retrospective analysis of the diagnostic laboratory submissions from 2016 to 2020 was performed to assess the antibiotic resistance of Staphylococcus pseudintermedius and determine locations in the hospital which might be acting as environmental source(s). Previous studies have identified a significant increase in infections with S. pseudintermedius. Samples were taken from the hospital environment by swabbing areas in the intensive care unit and anesthesia preparation room and bacterial species identified. Isolates obtained from patients were then examined regarding the ability to form biofilm, an important phenotype on hospital-related infection. In addition, veterinary hospital associated strains of S. pseudintermedius were used to determine the bactericidal effect of the used disinfectant, applying the hospital current protocol, by comparing the efficacy against S. pseudintermediius and a strain of Staphylococcus aureus from a dog. The isolates identified were resistant to commonly used antibiotics such as enrofloxacin and cephalosporins, and 45% percent of those were methicillin resistant. The environmental survey in the hospital identified S. pseudintermedius in the pre-anesthesia area, although the isolate was killed by the current used disinfection protocol. A few disease associated bacteria were evaluated for biofilm formation in comparison to a dog isolate of Staphylococcus aureus, demonstrating strong ability to form biofilms.
基金Supported by the Scientific and Technological Project of Shiyan City of Hubei Province,No.21Y32the Medical Research Project of Hubei Pediatric Alliance,No.HPAMRP202114.
文摘BACKGROUND Although neonatal Staphylococcus aureus pneumonia is common and usually curable,it can also be refractory and life-threatening.Herein,we report a case of severe neonatal community-acquired methicillin-resistant Staphylococcus aureus(CA-MRSA)necrotizing pneumonia with bilateral recurrent pyopneumothorax,respiratory failure,heart failure,and cardiac arrest.We hope our report will add to the understanding of this disease.CASE SUMMARY An 18-d-old boy presented with cough for five days,fever for three days,and dyspnea for two days.Preadmission chest radiograph revealed high-density shadows in both lungs.On admission,his oxygen saturation fluctuated around 90%under synchronized intermittent mandatory ventilation.He was unconscious,with dyspnea,weak heart sounds and hepatomegaly.Moist crackles were present throughout his left lung,while the breath sounds in the right lung were decreased.After high-frequency oscillatory ventilation,empiric antimicrobials(meropenem and vancomycin),improved circulation,and right pleural cavity drainage for right pneumothorax(approximately 90%compression),his oxygen saturation level stayed above 95%,and recruitment of the right lung was observed.His condition did not deteriorate until the 5th day of hospitalization(DOH 5).On the morning of DOH 5,his oxygen saturation decreased.Subsequent chest radiograph showed bilateral pneumothorax with nearly 100%compression of the left lung.Desaturation was not relieved after urgent left pleural cavity drainage,and cardiac arrest occurred soon thereafter.Although his spontaneous heartbeat returned through emergency resuscitation and salvage antibacterial therapy(linezolid and levofloxacin)was administered given the detection and antimicrobial susceptibility of MRSA,he showed no improvement,with recurrent pyopneumothorax and continued drainage of purulent fluid and necrotic lung tissue fragments from the pleural cavity.Eventually,his parents refused extracorporeal membrane oxygenation(ECMO)and gave up all the treatments,and the newborn passed away soon after withdrawal on DOH 13.CONCLUSION Neonatal MRSA pneumonia can be refractory and lethal,especially in cases where necrotizing pneumonia leads to extensive lung necrosis and recurrent pneumothorax.Despite treatment with linezolid and other medical measures,it may still be ineffective.Currently,ECMO has been a remedial therapy,but if the lung tissue is too severely eroded to be repaired,it may be useless unless the infection can be controlled and lung transplantation can be performed.Regardless of whether ECMO is initiated,the key to successful treatment is to achieve control over the pneumonia caused by MRSA as soon as possible and to reverse lung injury as much as possible.
文摘The coagulase-negative staphylococci (CoNS) group was considered saprophytic or rarely pathogenic for many years. Since the first case of septicemia caused by CoNS, there has been a progressive increase in the prevalence of healthcare-associated infections caused by CoNS. The CoNS group has emerged as one of the main causes of nosocomial infections related to vascular catheters and prostheses, especially among immunocompromised patients. This gradual increase in infections is due to the change in the relationship between patients and procedures since CoNS are closely related to devices implanted in the human body. CoNS are successful in colonizing the host because they have several virulence mechanisms, such as biofilm formation and production of enzymes and toxins, in addition to several mechanisms of resistance to antimicrobials. Despite their great clinical relevance, few studies have focused on CoNS’s pathogenicity and resistance to antimicrobials, which reveals the current need to better understand the factors by which this group became pathogenic to humans and other animals. This review aims to synthesize the aspects related to the pathogenicity and antimicrobial resistance in CoNS.
基金Supported by Project of Innovation and Entrepreneurship Training Program for College Students in Guangxi Zhuang Autonomous Region in 2022(S202210599060)Basic Ability Improvement Project for Young and Middle-aged Teachers in Guangxi Zhuang Autonomous Region in 2020(2020KY13027)Project of Scientific Research and Technological Development Plan of Baise City in 2020(Encyclopedia[2020]No.47).
文摘[Objectives]To observe the effects of daphnetin on mastitis induced by Staphylococcus aureus in mice.[Methods]18 postpartum ICR female mice were used to establish mastitis animal model,and were randomly divided into three groups(A,B,and C)with 6 mice in each group.Group A:blank control group;group B:S.Aureus model group;group C:S.Aureus model+daphnetin group.The experimental groups were injected 1 mL of 1.0×104 CFU/100μL of S.aureus of along the nipple catheter.The suspension was placed in the 3 rd and 4 th pairs of mammary glands,and the control group was injected with the same dose of normal saline.On the second day after infection,the rats in group A,B and C were given drugs by gavage,while the rats in group A and B were given normal saline and the rats in group C were given daphnetin once a day for 6 consecutive days.Blood samples were collected from living eyeballs,and blood cells were analyzed by automatic flow cytometer after anticoagulation.[Results]The NLR and Systemie Immune Inflammati-on Index(SII)in the blood of mastitis mice induced by S.aureus were significantly higher than those in the control group(P<0.01),suggesting that neutrophil to lymphocyte ratio(NLR)and SII can be used as diagnostic indicators of mastitis,and the levels of NLR and SII decreased significantly after daphnetin intervention.[Conclusions]NLR and SII showed high levels in mastitis mice,which are valuable for the diagnosis of mastitis and the evaluation of its prognosis.After the intervention of daphnetin,both of them decreased significantly,indicating that daphnetin has a good prognosis trend in mastitis mice induced by S.aureus.