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Albuquerque Borges MGDS, de Oliveira E Lima L, Veras ACMF, Ferreira RC, da Nóbrega Alves D, de Medeiros IA, Magnani M, Sobral MV, Dias de Castro R, Relison Tintino S, de Morais Oliveira-Tintino CD, Coutinho HDM, Guerra FQS, de Barros DB, de Oliveira MBM. Cytotoxicity and Biological Activities of Geopopolis Extract from the Stingless bee (Melipona scutellaris) in Isolates of Staphylococcus aureus. Chem Biodivers 2024; 21:e202301982. [PMID: 38608157 DOI: 10.1002/cbdv.202301982] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2023] [Revised: 04/11/2024] [Accepted: 04/12/2024] [Indexed: 04/14/2024]
Abstract
Geopropolis resins are produced by stingless bees (Meliponinae), developed from the collection of resinous materials, waxes and exudates, from the flora of the region where stingless bees are present, in addition to the addition of clay or earth in its composition. Several biological activities are attributed to Ethanol Extracts of Geopropolis (EEGP). The bioactive properties are associated with the complex chemical composition that the samples have. This work aims to evaluate the biological activities of the EEGP, in order to contribute with a natural therapeutic alternative, to face infections, mainly those caused by resistant strains of Staphylococcus aureus. The EEGP MIC tests showed antibacterial activity against two strains of S. aureus, both at concentrations of 550 μg/mL. The MBC performed with the inhibition values showed that the EEGP has bacteriostatic activity in both strains. Biofilm inhibition rates exhibited an average value greater than 65 % at the highest concentration. The EEGP antioxidant potential test showed good antioxidant activity (IC50) of 11.05±1.55 μg/mL. In the cytotoxicity test against HaCat cells, after 24 hours, EEGP induced cell viability at the three tested concentrations (550 μg/mL: 81.68±3.79 %; 1100 μg/mL: 67.10±3.76 %; 2200 μg/mL: 67.40±1.86 %). In view of the above, the safe use of EEGP from the brazilian northeast could be proven by the cytotoxicity test, and its use as an antioxidant and antibacterial agent has proven to be effective, as an alternative in combating oxidative stress and microorganisms such as S. aureus, which, through the spread and ongoing evolution of drug resistance, generates an active search for effective solutions.
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Affiliation(s)
| | | | | | - Rafael Carlos Ferreira
- Programa de Pós Graduação em Produtos Naturais e Sintéticos Bioativos, Universidade Federal da Paraíba, João Pessoa, Brasil
| | | | | | - Marciane Magnani
- Departamento de Engenharia de Alimentos, Universidade Federal da Paraíba, João Pessoa, Brasil
| | - Marianna Vieira Sobral
- Programa de Pós Graduação em Produtos Naturais e Sintéticos Bioativos, Universidade Federal da Paraíba, João Pessoa, Brasil
| | - Ricardo Dias de Castro
- Departamento de Odontologia Clínica e Social, Universidade Federal da Paraíba, João Pessoa, Brasil
| | - Saulo Relison Tintino
- Departamento de Química Biológica, Universidade Regional do Cariri, Crato, Ceará, Brasil
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Callejón Fernández M, Abreu Rodríguez R, Arias Á, Aguirre-Jaime A, Castro Hernández MB, Ramos Real MJ, Pedroso Fernández Y, Lecuona M. The Impact of MRSA Colonization on Healthcare-Associated Infections in Long-Term Care Facility Residents: A Whole-Genome Sequencing-Based Study. Microorganisms 2023; 11:2842. [PMID: 38137985 PMCID: PMC10745794 DOI: 10.3390/microorganisms11122842] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2023] [Revised: 11/21/2023] [Accepted: 11/21/2023] [Indexed: 12/24/2023] Open
Abstract
Methicillin-resistant Staphylococcus aureus (MRSA) colonization has been considered a risk factor for the development of infection, however, there are no studies that have compared the colonizing and infecting strains using whole-genome sequencing (WGS). The aim of this study is to determine the prevalence of and risk factors for MRSA colonization among long-term care facilities (LTCF) residents of Tenerife (Spain), and to analyze the epidemiological relationship between the colonizing and infecting strains using WGS. A point-prevalence study was carried out at 14 LTCFs in Tenerife from October 2020 to May 2021. Nasal swabs were cultured for MRSA. Colonized residents were followed up for two years. A phylogenetic comparison between colonization and infection strains was performed using WGS. A total of 764 residents were included. The prevalence of colonization by MRSA was 28.1% (n = 215), of which 12 (5.6%) subsequently developed infection. A close genetic relationship between colonization and infection isolates was found in three of the four (75%) residents studied. Our study confirms that colonized residents can develop serious MRSA infections from the same nasal colonization strain. Given the high prevalence of MRSA colonization in these centers, it is necessary to implement strategies with preventive measures to avoid the development of infection and the transmission of MRSA.
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Affiliation(s)
- Manuel Callejón Fernández
- Microbiology and Infection Control Service, University Hospital of the Canary Island (HUC), 38320 La Laguna, Spain; (M.B.C.H.); (M.J.R.R.); (Y.P.F.); (M.L.)
- Doctoral Program in Medical and Pharmaceutical Sciences, Development and Quality of Life, University of La Laguna (ULL), Campus de Ofra s/n, 38071 Santa Cruz de Tenerife, Spain
| | - Rossana Abreu Rodríguez
- Department of Preventive Medicine and Public Health, University of La Laguna (ULL), Campus de Ofra s/n, 38200 Santa Cruz de Tenerife, Spain; (R.A.R.); (Á.A.)
| | - Ángeles Arias
- Department of Preventive Medicine and Public Health, University of La Laguna (ULL), Campus de Ofra s/n, 38200 Santa Cruz de Tenerife, Spain; (R.A.R.); (Á.A.)
| | - Armando Aguirre-Jaime
- Institute of Care Research, Nurses Association of Santa Cruz de Tenerife, C. San Martin, 63, 38001 Santa Cruz de Tenerife, Spain;
| | - María Beatriz Castro Hernández
- Microbiology and Infection Control Service, University Hospital of the Canary Island (HUC), 38320 La Laguna, Spain; (M.B.C.H.); (M.J.R.R.); (Y.P.F.); (M.L.)
| | - María José Ramos Real
- Microbiology and Infection Control Service, University Hospital of the Canary Island (HUC), 38320 La Laguna, Spain; (M.B.C.H.); (M.J.R.R.); (Y.P.F.); (M.L.)
| | - Yanet Pedroso Fernández
- Microbiology and Infection Control Service, University Hospital of the Canary Island (HUC), 38320 La Laguna, Spain; (M.B.C.H.); (M.J.R.R.); (Y.P.F.); (M.L.)
| | - María Lecuona
- Microbiology and Infection Control Service, University Hospital of the Canary Island (HUC), 38320 La Laguna, Spain; (M.B.C.H.); (M.J.R.R.); (Y.P.F.); (M.L.)
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3
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Alves PJ, Gryson L, Hajjar J, Lepelletier D, Reners M, Rodríguez Salazar J, Simon A. Role of antiseptics in the prevention and treatment of infections in nursing homes. J Hosp Infect 2023; 131:58-69. [PMID: 36216172 DOI: 10.1016/j.jhin.2022.09.021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2022] [Revised: 09/16/2022] [Accepted: 09/26/2022] [Indexed: 11/07/2022]
Abstract
Inadequate infection control, wound care, and oral hygiene protocols in nursing homes pose challenges to residents' quality of life. Based on the outcomes from a focus group meeting and a literature search, this narrative review evaluates the current and potential roles of antiseptics within nursing home infection management procedures. We examine contemporary strategies and concerns within the management of meticillin-resistant Staphylococcus aureus (MRSA; including decolonization regimes), chronic wound care, and oral hygiene, and review the available data for the use of antiseptics, with a focus on povidone-iodine. Compared with chlorhexidine, polyhexanide, and silver, povidone-iodine has a broader spectrum of antimicrobial activity, with rapid and potent activity against MRSA and other microbes found in chronic wounds, including biofilms. As no reports of bacterial resistance or cross-resistance following exposure to povidone-iodine exist, it may be preferable for MRSA decolonization compared with mupirocin and chlorhexidine, which can lead to resistant MRSA strains. Povidone-iodine oral products have greater efficacy against oral pathogens compared with other antiseptics such as chlorhexidine mouthwash, highlighting the clinical benefit of povidone-iodine in oral care. Additionally, povidone-iodine-based products, including mouthwash, have demonstrated rapid in-vitro virucidal activity against SARS-CoV-2 and may help reduce its transmission if incorporated into nursing home coronavirus 2019 control protocols. Importantly, povidone-iodine activity is not adversely affected by organic material, such as that found in chronic wounds and the oral cavity. Povidone-iodine is a promising antiseptic agent for the management of infections in the nursing home setting, including MRSA decolonization procedures, chronic wound management, and oral care.
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Affiliation(s)
- P J Alves
- Wounds Research Laboratory, Centre for Interdisciplinary Research in Health (CIIS), Universidade Católica Portuguesa, Portugal.
| | - L Gryson
- Belgian Defence Medical Component, Brussels, Belgium
| | - J Hajjar
- Infection Control Practitioner, Consultant, Pau, France
| | - D Lepelletier
- Hospital Hygiene Department, Nantes University Hospital, Nantes, France
| | - M Reners
- Private Dental Practice, Liège, Belgium
| | | | - A Simon
- Infection Control Team, Groupe Hospitalier Jolimont, Haine Saint-Paul, Belgium
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4
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Gowler CD, Slayton RB, Reddy SC, O’Hagan JJ. Improving mathematical modeling of interventions to prevent healthcare-associated infections by interrupting transmission or pathogens: How common modeling assumptions about colonized individuals impact intervention effectiveness estimates. PLoS One 2022; 17:e0264344. [PMID: 35226689 PMCID: PMC8884501 DOI: 10.1371/journal.pone.0264344] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2021] [Accepted: 02/08/2022] [Indexed: 12/03/2022] Open
Abstract
Mathematical models are used to gauge the impact of interventions for healthcare-associated infections. As with any analytic method, such models require many assumptions. Two common assumptions are that asymptomatically colonized individuals are more likely to be hospitalized and that they spend longer in the hospital per admission because of their colonization status. These assumptions have no biological basis and could impact the estimated effects of interventions in unintended ways. Therefore, we developed a model of methicillin-resistant Staphylococcus aureus transmission to explicitly evaluate the impact of these assumptions. We found that assuming that asymptomatically colonized individuals were more likely to be admitted to the hospital or spend longer in the hospital than uncolonized individuals biased results compared to a more realistic model that did not make either assumption. Results were heavily biased when estimating the impact of an intervention that directly reduced transmission in a hospital. In contrast, results were moderately biased when estimating the impact of an intervention that decolonized hospital patients. Our findings can inform choices modelers face when constructing models of healthcare-associated infection interventions and thereby improve their validity.
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Affiliation(s)
- Camden D. Gowler
- Division of Healthcare Quality Promotion, Centers for Disease Control and Prevention, Atlanta, Georgia, United States of America
- Department of Ecology and Evolutionary Biology, University of Michigan, Ann Arbor, Michigan, United States of America
| | - Rachel B. Slayton
- Division of Healthcare Quality Promotion, Centers for Disease Control and Prevention, Atlanta, Georgia, United States of America
| | - Sujan C. Reddy
- Division of Healthcare Quality Promotion, Centers for Disease Control and Prevention, Atlanta, Georgia, United States of America
| | - Justin J. O’Hagan
- Division of Healthcare Quality Promotion, Centers for Disease Control and Prevention, Atlanta, Georgia, United States of America
- * E-mail:
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Amelia S, Wahyuni DD, Yunita R, Rozi MF. The Active Surveillance of Staphylococcus aureus using Polymerase Chain Reaction-based Identification Method among Hospitalized-patient of Haji Adam Malik General Hospital, Medan, Indonesia. Open Access Maced J Med Sci 2021. [DOI: 10.3889/oamjms.2021.6646] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
BACKGROUND: Active surveillance of methicillin-resistant Staphylococcus aureus (MRSA) carriers is associated with the lower incidence of bacteremia and lower mortality rates throughout literature; yet, this important step still remains problematic for developing countries, particularly Indonesia.
AIM: The study aimed to demonstrate MRSA colonization rate in Haji Adam Malik Hospital, Medan, Indonesia.
MATERIALS AND METHODS: The study enrolled 200 mucocutaneous isolates obtained from hospitalized patients during a 1-year period of study (2018). VITEK-2 system in addition to standard bacterial identification, such as gram staining, latex agglutination test, and hemolysis pattern, was performed to select S. aureus colonies in two different laboratories, Microbiology laboratory of Haji Adam Malik General Hospital and Multidisciplinary Laboratory, Faculty of Medicine, Universitas Sumatera Utara, for polymerase chain reaction (PCR) examination.
RESULTS: Based on the VITEK-2 system preliminary identification, there were 80 S. aureus colonies which then underwent PCR examination. Through standard PCR assay, there were 32 bacterial isolates contained the mecA gene and it can be determined MRSA colonization rate of the hospital was 16% with consistent results of standard bacterial identification.
CONCLUSIONS: Active surveillance of MRSA carriers is mandatory and urged it as a regular program in a hospital setting to decrease MRSA transmission rate.
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Opollo MS, Otim TC, Kizito W, Thekkur P, Kumar AMV, Kitutu FE, Kisame R, Zolfo M. Infection Prevention and Control at Lira University Hospital, Uganda: More Needs to Be Done. Trop Med Infect Dis 2021; 6:tropicalmed6020069. [PMID: 34062871 PMCID: PMC8167580 DOI: 10.3390/tropicalmed6020069] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2021] [Revised: 04/28/2021] [Accepted: 04/29/2021] [Indexed: 12/17/2022] Open
Abstract
Globally, 5–15% of hospitalized patients acquire infections (often caused by antimicrobial-resistant microbes) due to inadequate infection prevention and control (IPC) measures. We used the World Health Organization’s (WHO) ‘Infection Prevention and Control Assessment Framework’ (IPCAF) tool to assess the IPC compliance at Lira University hospital (LUH), a teaching hospital in Uganda. We also characterized challenges in completing the tool. This was a hospital-based, cross-sectional study conducted in November 2020. The IPC focal person at LUH completed the WHO IPCAF tool. Responses were validated, scored, and interpreted per WHO guidelines. The overall IPC compliance score at LUH was 225/800 (28.5%), implying a basic IPC compliance level. There was no IPC committee, no IPC team, and no budgets. Training was rarely or never conducted. There was no surveillance system and no monitoring/audit of IPC activities. Bed capacity, water, electricity, and disposal of hospital waste were adequate. Disposables and personal protective equipment were not available in appropriate quantities. Major challenges in completing the IPCAF tool were related to the detailed questions requiring repeated consultation with other hospital stakeholders and the long time it took to complete the tool. IPC compliance at LUH was not optimal. The gaps identified need to be addressed urgently.
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Affiliation(s)
- Marc Sam Opollo
- Department of Public Health, Faculty of Health Sciences, Lira University, 1035 Lira, Uganda;
- Correspondence: ; Tel.: +256-772-900-834
| | - Tom Charles Otim
- Department of Public Health, Faculty of Health Sciences, Lira University, 1035 Lira, Uganda;
| | - Walter Kizito
- Médecins Sans Frontières, MSF-B, 1050 Brussels, Belgium;
| | - Pruthu Thekkur
- International Union against Tuberculosis and Lung Disease (The Union), 75006 Paris, France; (P.T.); (A.M.V.K.)
| | - Ajay M. V. Kumar
- International Union against Tuberculosis and Lung Disease (The Union), 75006 Paris, France; (P.T.); (A.M.V.K.)
- The Union South-East Asia Office, New Delhi 110016, India
- Yenepoya Medical College, Yenepoya (Deemed to be University), Mangaluru 575018, India
| | - Freddy Eric Kitutu
- Sustainable Pharmaceutical Systems (SPS) Unit, Pharmacy Department, Makerere University School of Health Sciences, 10217 Kampala, Uganda;
| | - Rogers Kisame
- Infectious Diseases Institute, Makerere University, 10217 Kampala, Uganda;
| | - Maria Zolfo
- Institute of Tropical Medicine, 2000 Antwerp, Belgium;
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Direct interactions between cationic liposomes and bacterial cells ameliorate the systemic treatment of invasive multidrug-resistant Staphylococcus aureus infections. NANOMEDICINE-NANOTECHNOLOGY BIOLOGY AND MEDICINE 2021; 34:102382. [PMID: 33771706 DOI: 10.1016/j.nano.2021.102382] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/02/2020] [Revised: 01/14/2021] [Accepted: 03/03/2021] [Indexed: 12/19/2022]
Abstract
Invasive infections caused by antibiotic-resistant Staphylococcus aureus have posed a great threat to human health. To tackle this problem, a cationic liposomal Curcumin (C-LS/Cur) was developed and its effect against antibiotic-resistant S. aureus was investigated in this study. As expected, C-LS/Cur exhibited greater bactericidal capacity compared with its counterparts, probably because the negatively charged S. aureus favors electrostatic interactions rather than intercalation with cationic liposomal vesicles at the beginning of endocytic process, thereby effectively delivering Cur to its targets. We confirmed this hypothesis by monitoring zeta potential variation, collecting visual evidences through CLSM, FCM and TEM, and determining binding kinetics by BLI. Moreover, an excellent therapeutic efficacy of C-LS/Cur against invasive murine infection was also observed, which was due to the enhanced accumulation and retention in the targets. Therefore, cationic liposomes have great potential for the clinical application in the treatment of invasive antibiotic-resistant S. aureus infections.
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Goes ICRDS, Romero LC, Turra AJ, Gotardi MA, Rodrigues TFSDO, Santos LDO, Dores JCD, Nascimento MUD, Cavalleri AC, Pinheiro-Hubinger L, Eller LKW, Pereira VC. Prevalence of nasal carriers of methicillin-resistant Staphylococcus aureus in primary health care units in Brazil. Rev Inst Med Trop Sao Paulo 2021; 63:e14. [PMID: 33656137 PMCID: PMC7924983 DOI: 10.1590/s1678-9946202163014] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2020] [Accepted: 01/21/2021] [Indexed: 11/22/2022] Open
Abstract
Nasal carriage of Staphylococcus aureus by healthcare workers is of great clinical importance as it facilitates the contamination of medical devices and cross-transmission. However, studies regarding the epidemiology and dissemination of S. aureus and Methicillin-resistant S. aureus (MRSA) within the Primary Health Care in Brazil are scarce. The current study aimed to detect and characterize S. aureus and MRSA strains from the nasal cavities of 63 healthcare working in primary health care units in order to determine the prevalence of S. aureus and MRSA, biofilm formation and resistance profile of these isolates. PCR reactions were performed for detecting mecA, icaA and icaD genes. The phenotypic antimicrobial susceptibility was assessed by the disk diffusion method and biofilm formation by the Congo Red Agar (CRA) method. The MRSA isolates were typed for the Staphylococcal Cassette Chromosome mec (SCCmec). The prevalence of nasal carriage of S. aureus was 74.6%, of which 72.3% were MRSA carrying SCCmec type I (24.4%), III (34.1%), IV (36.6%). Two (4.9%) isolates presented a non-typeable cassette by the performed technique. The antimicrobial susceptibility evaluation evidenced penicillin resistance in 66.1% of S. aureus, erythromycin resistance in 49.2%, while 37.3% were resistant to oxacillin, 28.8% to cefoxitin, 5.1% to levofloxacin and 5.1% to clindamycin. All isolates were biofilm producers and 96.6% of the strains contained the ica biofilm-forming genes (icaA and/or icaD). We have demonstrated a high prevalence of S. aureus and MRSA carriage among health care working in Primary Health Care units, the presence of SCCmec types I, III and IV, in addition to their high ability to form biofilm, factors that possibly contribute to the dissemination and persistence of these pathogens within the primary care services. These observations highlight the importance of broadening the perspective of Health Care-Associated Infections prevention, including all health care levels, which are currently little explored. In addition, the dynamics and resistance mechanisms of S. aureus transmission still need to be further clarified to enable the implementation of more effective prevention measures.
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Affiliation(s)
| | - Letícia Calixto Romero
- Universidade Estadual Paulista, Departamento de Ciências Químicas e Biológicas, Botucatu, São Paulo, Brazil
| | - Ana Julia Turra
- Universidade do Oeste Paulista, Presidente Prudente, São Paulo, Brazil
| | | | | | | | | | | | | | - Luiza Pinheiro-Hubinger
- Universidade Estadual Paulista, Departamento de Ciências Químicas e Biológicas, Botucatu, São Paulo, Brazil
- Instituto Lauro de Souza Lima, Departamento de Patologia, Bauru, São Paulo, Brazil
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Tang A, Kwok KO, Wei VWI, Chen H, Wong SYS, Tam WWS. Synergistic Effect of Combination Interventions for Methicillin-Resistant Staphylococcus aureus Transmission Control in Nursing Homes: A Computation Modelling Evaluation with Heterogeneous Contact Mixing. Antibiotics (Basel) 2021; 10:227. [PMID: 33668327 PMCID: PMC7996172 DOI: 10.3390/antibiotics10030227] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2021] [Revised: 02/12/2021] [Accepted: 02/18/2021] [Indexed: 11/17/2022] Open
Abstract
The endemic threat of methicillin-resistant Staphylococcus aureus (MRSA) in nursing homes poses a serious and escalating challenge to public health administration in infection control. Nursing homes are considered as major reservoirs for MRSA colonization, with considerable high levels of colonization prevalence. We employed a computation model to evaluate effects of three intervention scenarios on MRSA colonization prevalence rate in nursing homes. Simulations were conducted using a deterministic compartmental model featuring heterogeneous contact matrix between residents and health-care workers (HCWs). Contact parameters were derived from a nursing home survey. Three intervention scenarios were simulated: (1) hand-hygiene compliance by HCWs, (2) screening-and-isolation upon admission, and (3) implementing both interventions at the same time. For every 10% reduction in average contamination duration in HCWs, the estimated average reduction in prevalence rate was 1.29 percentage point compared with the prevalence rate before the intervention was implemented. Screening-and-isolation intervention resulted in an average reduction of 19.04 percentage point in prevalence rate (S.D. = 1.58; 95% CI = 18.90-19.18). In intervention scenario 3, synergistic effects were observed when implementing hand-hygiene compliance by HCWs and screening-and-isolation together. Our results provide evidence showing that implementing multiple interventions together has a synergistic effect on colonization prevalence reduction.
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Affiliation(s)
- Arthur Tang
- Department of Software, Sungkyunkwan University, Suwon 16419, Korea;
| | - Kin On Kwok
- JC School of Public Health and Primary Care, The Chinese University of Hong Kong, Hong Kong 999077, China; (V.W.I.W.); (S.Y.S.W.)
- Stanley Ho Centre for Emerging Infectious Diseases, The Chinese University of Hong Kong, Hong Kong 999077, China
- Shenzhen Research Institute, The Chinese University of Hong Kong, Shenzhen 518057, China
| | - Vivian Wan In Wei
- JC School of Public Health and Primary Care, The Chinese University of Hong Kong, Hong Kong 999077, China; (V.W.I.W.); (S.Y.S.W.)
| | - Hong Chen
- Centre for Health Protection, Department of Health, Hong Kong 999077, China;
| | - Samuel Yeung Shan Wong
- JC School of Public Health and Primary Care, The Chinese University of Hong Kong, Hong Kong 999077, China; (V.W.I.W.); (S.Y.S.W.)
| | - Wilson Wai Sun Tam
- Alice Lee Centre for Nursing Studies, National University of Singapore, Singapore 117597, Singapore;
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Reducing Spread of Infections with a Photocatalytic Reactor-Potential Applications in Control of Hospital Staphylococcus aureus and Clostridioides difficile Infections and Inactivation of RNA Viruses. Infect Dis Rep 2021; 13:58-71. [PMID: 33440699 PMCID: PMC7838977 DOI: 10.3390/idr13010008] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/13/2020] [Revised: 01/04/2021] [Accepted: 01/05/2021] [Indexed: 02/04/2023] Open
Abstract
Contaminated surfaces and indoor environments are important sources of infectious spread within hospital and non-hospital facilities. Bacterial infections such as infections with Clostridioides (formerly Clostridium) difficile (C. difficile) and Staphylococcus aureus (S. aureus) and its antibiotic resistant strains continue to pose a significant risk to healthcare workers and patients. Additionally, the recent emergence of the coronavirus disease 2019 (COVID-19) pandemic, which is caused by the novel coronavirus, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), highlights the need for safe and effective methods to decontaminate surfaces to control infection spread in hospitals and the community. To address these critical needs, we tested a photocatalytic reactor decontamination method to disinfect contaminated surfaces in a hospital and a laboratory setting. By placing the reactor in a test hospital room, growth of S. aureus and C. difficile were significantly reduced compared with a control room. Additionally, using a model enveloped positive-sense single-stranded RNA virus, dengue virus type 2 (DENV2), we showed that the use of the photocatalytic reactor reduces viral infectivity. Collectively, the results demonstrate the potential utility of photocatalytic reactors in reducing the spread of highly contagious bacterial and viral infections through contaminated surfaces and environments.
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Wu S, Lei L, Bao C, Liu J, Weir MD, Ren K, Schneider A, Oates TW, Liu J, Xu HHK. An injectable and antibacterial calcium phosphate scaffold inhibiting Staphylococcus aureus and supporting stem cells for bone regeneration. MATERIALS SCIENCE & ENGINEERING. C, MATERIALS FOR BIOLOGICAL APPLICATIONS 2020; 120:111688. [PMID: 33545850 DOI: 10.1016/j.msec.2020.111688] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/07/2020] [Revised: 10/26/2020] [Accepted: 10/27/2020] [Indexed: 02/08/2023]
Abstract
Staphylococcus aureus (S. aureus) is the major pathogen for osteomyelitis, which can lead to bone necrosis and destruction. There has been no report on antibacterial calcium phosphate cement (CPC) against S. aureus. The aims of this study were to: (1) develop novel antibacterial CPC-chitosan-alginate microbead scaffold; (2) investigate mechanical and antibacterial properties of CPC-chitosan-penicillin-alginate scaffold; (3) evaluate the encapsulation and delivery of human umbilical cord mesenchymal stem cells (hUCMSCs). Flexural strength, elastic modulus and work-of-fracture of the CPC-chitosan-penicillin-alginate microbeads scaffold and CPC-chitosan scaffold were evaluated. Penicillin release profile and antibacterial effects on S. aureus were determined. The hUCMSC delivery and release from penicillin-alginate microbeads were investigated. Injectable CPC-chitosan-penicillin-alginate microbeads scaffold was developed for the first time. CPC-chitosan-penicillin-alginate microbeads scaffold had a flexural strength of 3.16 ± 0.55 MPa, matching that of cancellous bone. With sustained penicillin release, the new scaffold had strong antibacterial effects on S. aureus, with an inhibition zone diameter of 32.2 ± 2.5 mm, greater than that of penicillin disk control (15.1 ± 2.0 mm) (p < 0.05). Furthermore, this injectable and antibacterial scaffold had no toxic effects, yielding excellent hUCMSC viability, which was similar to that of CPC control without antibacterial activity (p > 0.05). CPC-chitosan-penicillin-microbeads scaffold had injectability, good strength, strong antibacterial effects, and good biocompatibility to support stem cell viability for osteogenesis. CPC-chitosan-penicillin-microbeads scaffold is promising for dental, craniofacial and orthopedic applications to combat infections and promote bone regeneration.
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Affiliation(s)
- Shizhou Wu
- Department of Orthopedic Surgery, West China Hospital, Sichuan University, Chengdu, Sichuan 610041, China; Biomaterials & Tissue Engineering Division, Department of Advanced Oral Sciences and Therapeutics, University of Maryland Dental School, Baltimore, MD 21201, USA
| | - Lei Lei
- State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, Sichuan 610041, China
| | - Chongyun Bao
- State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, Sichuan 610041, China
| | - Jin Liu
- Biomaterials & Tissue Engineering Division, Department of Advanced Oral Sciences and Therapeutics, University of Maryland Dental School, Baltimore, MD 21201, USA; Key Laboratory of Shannxi for Craniofacial Precision Medicine Research, Clinical Research Center of Shannxi for Dental and Maxillofacial Diseases, College of Stomatology, Xi'an Jiaotong University, Shannxi 710004, China
| | - Michael D Weir
- Biomaterials & Tissue Engineering Division, Department of Advanced Oral Sciences and Therapeutics, University of Maryland Dental School, Baltimore, MD 21201, USA
| | - Ke Ren
- Department of Neural and Pain Sciences, School of Dentistry, Program in Neuroscience, University of Maryland, Baltimore, MD 21201, USA
| | - Abraham Schneider
- Department of Oncology and Diagnostic Sciences, University of Maryland School of Dentistry, Baltimore, USA; Marlene and Stewart Greenebaum Cancer Center, University of Maryland School of Medicine, Baltimore, MD 21201, USA
| | - Thomas W Oates
- Biomaterials & Tissue Engineering Division, Department of Advanced Oral Sciences and Therapeutics, University of Maryland Dental School, Baltimore, MD 21201, USA
| | - Jun Liu
- State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, Sichuan 610041, China.
| | - Hockin H K Xu
- Biomaterials & Tissue Engineering Division, Department of Advanced Oral Sciences and Therapeutics, University of Maryland Dental School, Baltimore, MD 21201, USA; Marlene and Stewart Greenebaum Cancer Center, University of Maryland School of Medicine, Baltimore, MD 21201, USA; Center for Stem Cell Biology and Regenerative Medicine, University of Maryland School of Medicine, Baltimore, MD 21201, USA.
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12
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Etter D, Corti S, Spirig S, Cernela N, Stephan R, Johler S. Staphylococcus aureus Population Structure and Genomic Profiles in Asymptomatic Carriers in Switzerland. Front Microbiol 2020; 11:1289. [PMID: 32670229 PMCID: PMC7328235 DOI: 10.3389/fmicb.2020.01289] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2020] [Accepted: 05/20/2020] [Indexed: 12/17/2022] Open
Abstract
Staphylococcus aureus is a leading cause for clinical infections and food intoxications, causing over 100,000 yearly cases of bacteremia in the United States and 434 food-borne outbreaks in the European Union. Approximately 30% of the population permanently carry S. aureus asymptomatically in their nasal cavity. The risk of infection and transmission to food items or the environment is higher in individuals that are nasally colonized. In addition, S. aureus can acquire various antimicrobial resistances leading to therapeutic failure, additional medical costs, and fatalities. Methicillin-resistant S. aureus (MRSA) cause a considerable burden of disease in humans and animals. MRSA carriage has been associated with animal and in particular livestock contact. Extensive current data on the virulence gene profiles, as well as data on antimicrobial resistance determinants is crucial in developing effective strategies to mitigate the burden of disease. To this end, we screened the anterior nares of 160 test subjects (87 pupils and 73 members of farmer families) in Switzerland for S. aureus carriage. A total of 73 S. aureus isolates were obtained. Factors such as exposure to farm or companion animals and personal medical history were recorded using a questionnaire. Using a DNA microarray, isolates were assigned to clonal complexes (CCs), and virulence and resistance gene profiles were determined. The collected strains were assigned to 20 CCs, among others CC1, CC7, CC8, CC15, CC30, CC45, CC97, and CC398. Two MRSA strains and one multiresistant isolate carrying genes blaZ/I/R, InuA, aadD, tetK, and fosB were isolated from farmers with intensive exposure to animals. Strains carrying pvl, causing severe skin lesions and necrotizing pneumonia, as well as tetracycline, erythromycin, and kanamycin resistance genes were found in individuals that had taken antibiotics during the last year. A variety of superantigenic toxin genes was detected, including among others, the toxic shock syndrome toxin (tst1), and various enterotoxins (sea, sec, sel, and the egc cluster). Contact to chickens was identified as a significant factor contributing to S. aureus colonization.
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Affiliation(s)
- Danai Etter
- Institute for Food Safety and Hygiene, Vetsuisse Faculty, University of Zurich, Zurich, Switzerland
- Institute of Food, Nutrition and Health, Department of Health Science and Technology, ETH Zürich, Zurich, Switzerland
| | - Sabrina Corti
- Institute for Food Safety and Hygiene, Vetsuisse Faculty, University of Zurich, Zurich, Switzerland
| | - Simona Spirig
- Institute for Food Safety and Hygiene, Vetsuisse Faculty, University of Zurich, Zurich, Switzerland
| | - Nicole Cernela
- Institute for Food Safety and Hygiene, Vetsuisse Faculty, University of Zurich, Zurich, Switzerland
| | - Roger Stephan
- Institute for Food Safety and Hygiene, Vetsuisse Faculty, University of Zurich, Zurich, Switzerland
| | - Sophia Johler
- Institute for Food Safety and Hygiene, Vetsuisse Faculty, University of Zurich, Zurich, Switzerland
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13
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da Cunha MG, de Cássia Orlandi Sardi J, Freires IA, Franchin M, Rosalen PL. Antimicrobial, anti-adherence and antibiofilm activity against Staphylococcus aureus of a 4-phenyl coumarin derivative isolated from Brazilian geopropolis. Microb Pathog 2020; 139:103855. [DOI: 10.1016/j.micpath.2019.103855] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2019] [Revised: 11/05/2019] [Accepted: 11/05/2019] [Indexed: 12/23/2022]
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14
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Lei H, Jones RM, Li Y. Quantifying the relative impact of contact heterogeneity on MRSA transmission in ICUs - a modelling study. BMC Infect Dis 2020; 20:6. [PMID: 31900118 PMCID: PMC6942315 DOI: 10.1186/s12879-019-4738-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2019] [Accepted: 12/24/2019] [Indexed: 12/17/2022] Open
Abstract
Background An efficient surface cleaning strategy would first target cleaning to surfaces that make large contributions to the risk of infections. Methods In this study, we used data from the literature about methicillin-resistant Staphylococcus aureus (MRSA) and developed an ordinary differential equations based mathematical model to quantify the impact of contact heterogeneity on MRSA transmission in a hypothetical 6-bed intensive care unit (ICU). The susceptible patients are divided into two types, these who are cared by the same nurse as the MRSA infected patient (Type 1) and these who are not (Type 2). Results The results showed that the mean MRSA concentration on three kinds of susceptible patient nearby surfaces was significantly linearly associated with the hand-touch frequency (p < 0.05). The noncompliance of daily cleaning on patient nearby high-touch surfaces (HTSs) had the most impact on MRSA transmission. If the HTSs were not cleaned, the MRSA exposure to Type 1 and 2 susceptible patients would increase 118.4% (standard deviation (SD): 33.0%) and 115.4% (SD: 30.5%) respectively. The communal surfaces (CSs) had the least impact, if CSs were not cleaned, the MRSA exposure to Type 1 susceptible patient would only increase 1.7% (SD: 1.3). The impact of clinical equipment (CE) differed largely for two types of susceptible patients. If the CE was not cleaned, the exposure to Type 1 patients would only increase 8.4% (SD: 3.0%), while for Type 2 patients, it can increase 70.4% (SD: 25.4%). Conclusions This study provided a framework to study the pathogen concentration dynamics on environmental surfaces and quantitatively showed the importance of cleaning patient nearby HTSs on controlling the nosocomial infection transmission via contact route.
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Affiliation(s)
- Hao Lei
- School of Public Health, Zhejiang University, Hangzhou, People's Republic of China. .,Zhejiang Institute of Research and Innovation, The University of Hong Kong, Lin An, Zhejiang, People's Republic of China.
| | - Rachael M Jones
- Department of Family and Preventive Medicine, School of Medicine, University of Utah, Salt Lake City, UT, USA
| | - Yuguo Li
- Zhejiang Institute of Research and Innovation, The University of Hong Kong, Lin An, Zhejiang, People's Republic of China.,Department of Mechanical Engineering, The University of Hong Kong, Pokfulam, Hong Kong, SAR, People's Republic of China
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15
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Wu S, Liu Y, Lei L, Zhang H. Virulence of methicillin-resistant Staphylococcus aureus modulated by the YycFG two-component pathway in a rat model of osteomyelitis. J Orthop Surg Res 2019; 14:433. [PMID: 31831035 PMCID: PMC6909630 DOI: 10.1186/s13018-019-1508-z] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/26/2019] [Accepted: 12/04/2019] [Indexed: 02/07/2023] Open
Abstract
Objectives Methicillin-resistant Staphylococcus aureus (MRSA) strains present an urgent medical problem in osteomyelitis cases. Our previous study indicated that the YycFG two-component regulatory pathway is associated with the bacterial biofilm organization of MRSA strains. The aim of this study was to investigate the regulatory roles of ASyycG in the bacterial biofilm formation and the pathogenicity of MRSA strains using an antisense RNA strategy. Methods An ASyycG-overexpressing MRSA clinical isolate was constructed. The bacterial growth was monitored, and the biofilm biomass on bone specimens was examined using scanning electron microscopy and confocal laser scanning microscopy. Furthermore, quantitative RT-PCR (QRT-PCR) analysis was used to measure the expression of yycF/G/H and icaA/D in the MRSA and ASyycG strains. The expression of the YycG protein was quantified by Western blot assays. We validated the role of ASyycG in the invasive ability and pathogenicity of the strains in vivo using histology and peptide nucleic acid fluorescent in situ hybridization. Results The results showed that overexpression of ASyycG lead to a reduction in biofilm formation and exopolysaccharide (EPS) synthesis compared to the control MRSA strains. The ASyycG strains exhibited decreased expression of the yycF/G/H and icaA/D genes. Furthermore, Western blot data showed that the production of the YycG protein was inhibited in the ASyycG strains. In addition, we demonstrated that ASyycG suppressed the invasive ability and pathogenicity of the strain in vivo using an SPF (specific pathogen free) rat model. Conclusion In summary, the overexpression of ASyycG leads to a reduction in biofilm formation and bacterial pathogenicity in vivo, which provides a potential target for the management of MRSA-induced osteomyelitis.
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Affiliation(s)
- Shizhou Wu
- Department of Orthopedics, West China Hospital, Sichuan University, No.37 Guoxue Alley, Chengdu City, 610041, Sichuan, China
| | - Yunjie Liu
- West China School of Public Health, Sichuan University, Chengdu, China
| | - Lei Lei
- State Key Laboratory of Oral Diseases, Department of Preventive Dentistry, West China Hospital of Stomatology, Sichuan University, NO.14 Renmin South Road, Chengdu City, 610041, Sichuan, China.
| | - Hui Zhang
- Department of Orthopedics, West China Hospital, Sichuan University, No.37 Guoxue Alley, Chengdu City, 610041, Sichuan, China.
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16
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Khader K, Thomas A, Jones M, Toth D, Stevens V, Samore MH. Variation and trends in transmission dynamics of Methicillin-resistant Staphylococcus aureus in veterans affairs hospitals and nursing homes. Epidemics 2019; 28:100347. [PMID: 31171468 PMCID: PMC7006838 DOI: 10.1016/j.epidem.2019.100347] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2019] [Revised: 05/25/2019] [Accepted: 05/28/2019] [Indexed: 02/02/2023] Open
Abstract
Variation and differences of MRSA transmission within and between healthcare settings are not well understood. This variability is critical for understanding the potential impact of infection control interventions and could aid in the evaluation of future intervention strategies. We fit a Bayesian transmission model to detailed individual-level MRSA surveillance data from over 230 Veterans Affairs (VA) hospitals and nursing homes. Our approach disentangles the effects of potential confounders, including length of stay, admission prevalence, and clearance, estimating dynamic transmission model parameters and temporal trends. The median baseline transmission rate in hospitals was approximately four-fold higher than in nursing homes, and declined in 46% of hospitals and 9% of nursing homes, resulting in a median transmission rate reduction of 43% across hospitals and an increase of 2% in nursing homes. For first admissions into an acute care facility, the median (range) importation probability was 10.5% (5.9%–18.4%), and was nearly twice as large, 18.7% (9.2%–37.4%), in nursing homes. This analysis found differences within and between hospitals and nursing homes. The transmission rate declined substantially in hospitals and remained stable in nursing homes, while admission prevalence was considerably higher in nursing homes than in hospitals.
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Affiliation(s)
- Karim Khader
- Informatics, Decision Enhancement, and Analytic Sciences (IDEAS) 2.0 Center, VA Salt Lake City Health Care System, 500 Foothill Drive Bldg. 182, Salt Lake City, UT, 84148, USA; Division of Epidemiology, University of Utah School of Medicine, 295 Chipeta Way, Salt Lake City, UT, 84132, USA.
| | - Alun Thomas
- Informatics, Decision Enhancement, and Analytic Sciences (IDEAS) 2.0 Center, VA Salt Lake City Health Care System, 500 Foothill Drive Bldg. 182, Salt Lake City, UT, 84148, USA; Division of Epidemiology, University of Utah School of Medicine, 295 Chipeta Way, Salt Lake City, UT, 84132, USA.
| | - Makoto Jones
- Informatics, Decision Enhancement, and Analytic Sciences (IDEAS) 2.0 Center, VA Salt Lake City Health Care System, 500 Foothill Drive Bldg. 182, Salt Lake City, UT, 84148, USA; Division of Epidemiology, University of Utah School of Medicine, 295 Chipeta Way, Salt Lake City, UT, 84132, USA.
| | - Damon Toth
- Informatics, Decision Enhancement, and Analytic Sciences (IDEAS) 2.0 Center, VA Salt Lake City Health Care System, 500 Foothill Drive Bldg. 182, Salt Lake City, UT, 84148, USA; Division of Epidemiology, University of Utah School of Medicine, 295 Chipeta Way, Salt Lake City, UT, 84132, USA.
| | - Vanessa Stevens
- Informatics, Decision Enhancement, and Analytic Sciences (IDEAS) 2.0 Center, VA Salt Lake City Health Care System, 500 Foothill Drive Bldg. 182, Salt Lake City, UT, 84148, USA; Division of Epidemiology, University of Utah School of Medicine, 295 Chipeta Way, Salt Lake City, UT, 84132, USA.
| | - Matthew H Samore
- Informatics, Decision Enhancement, and Analytic Sciences (IDEAS) 2.0 Center, VA Salt Lake City Health Care System, 500 Foothill Drive Bldg. 182, Salt Lake City, UT, 84148, USA; Division of Epidemiology, University of Utah School of Medicine, 295 Chipeta Way, Salt Lake City, UT, 84132, USA.
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17
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Majed H, Johnston T, Kelso C, Monachino E, Jergic S, Dixon NE, Mylonakis E, Kelso MJ. Structure-activity relationships of pyrazole-4-carbodithioates as antibacterials against methicillin-resistant Staphylococcus aureus. Bioorg Med Chem Lett 2018; 28:3526-3528. [PMID: 30297281 DOI: 10.1016/j.bmcl.2018.09.038] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2018] [Revised: 09/23/2018] [Accepted: 09/28/2018] [Indexed: 12/20/2022]
Abstract
Methicillin-resistant Staphylococcus aureus (MRSA) is a major cause of serious hospital-acquired infections and is responsible for significant morbidity and mortality in residential care facilities. New agents against MRSA are needed to combat rising resistance to current antibiotics. We recently reported 5-hydroxy-3-methyl-1-phenyl-1H-pyrazole-4-carbodithioate (HMPC) as a new bacteriostatic agent against MRSA that appears to act via a novel mechanism. Here, twenty nine analogs of HMPC were synthesized, their anti-MRSA structure-activity relationships evaluated and selectivity versus human HKC-8 cells determined. Minimum inhibitory concentrations (MIC) ranged from 0.5 to 64 μg/mL and up to 16-fold selectivity was achieved. The 4-carbodithioate function was found to be essential for activity but non-specific reactivity was ruled out as a contributor to antibacterial action. The study supports further work aimed at elucidating the molecular targets of this interesting new class of anti-MRSA agents.
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Affiliation(s)
- Hiwa Majed
- School of Chemistry, University of Wollongong, and Illawarra Health and Medical Research Institute, Wollongong, New South Wales 2522, Australia
| | - Tatiana Johnston
- Department of Infectious Disease, Rhode Island Hospital, Alpert Medical School of Brown University, Providence, RI 02903, USA
| | - Celine Kelso
- School of Chemistry, University of Wollongong, and Illawarra Health and Medical Research Institute, Wollongong, New South Wales 2522, Australia
| | - Enrico Monachino
- School of Chemistry, University of Wollongong, and Illawarra Health and Medical Research Institute, Wollongong, New South Wales 2522, Australia
| | - Slobodan Jergic
- School of Chemistry, University of Wollongong, and Illawarra Health and Medical Research Institute, Wollongong, New South Wales 2522, Australia
| | - Nicholas E Dixon
- School of Chemistry, University of Wollongong, and Illawarra Health and Medical Research Institute, Wollongong, New South Wales 2522, Australia
| | - Eleftherios Mylonakis
- Department of Infectious Disease, Rhode Island Hospital, Alpert Medical School of Brown University, Providence, RI 02903, USA
| | - Michael J Kelso
- School of Chemistry, University of Wollongong, and Illawarra Health and Medical Research Institute, Wollongong, New South Wales 2522, Australia.
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