Frequency and antimicrobial susceptibility of aerobic bacterial vaginal isolates.

PubMed

Tariq, Nabia; Jaffery, Tara; Ayub, Rukhsana; Alam, Ali Yawar; Javid, Mahmud Haider; Shafique, Shamsa

2006-03-01

To determine the frequency and antimicrobial susceptibility of aerobic bacterial isolates from high vaginal swab cultures. Cross-sectional survey. Shifa International Hospital, Islamabad, from January 2003 to February 2004. The subjects included 136 symptomatic women attending Obstetrics and Gynecology Out-Patient Department. A proforma was filled to document the demographic details, presenting complaint and examination findings. High vaginal swabs were taken for gram staining, culture and antimicrobial sensitivity testing using standard microbiologic techniques. Normal flora was isolated in 30% of the cases, followed by Candida spp. (21.3%), Enterococcus spp. (14.7%), E.coli (10.2%), Beta hemolytic Streptococcus spp. (7.3%), Staphylococcus spp. (4.4%), Enterobacter spp. (4.4%), while Streptococcus pyogenes, Staphylococcus epidermidis and Klebsiella spp. were isolated 1.5% each. Enterococcus, Staphylococcus and Streptococcus were mostly sensitive to penicillin and amoxicillin while E.coli and Klebsiella were sensitive to (piperacillin-Tazobactum, Imipenem and vancomycin. Enterococci species showed significant resistance to aminoglycoside antibiotics (68.8% to 81.3%) resistance to vancomycin was 5%. Thirty percent of symptomatic patients had normal flora on culture. Candida spp was the most frequent pathogen isolated. Co-amoxiclav should be used as empiric therapy until culture-sensitivity report is available.

In vitro activity of flomoxef and cefazolin in combination with vancomycin.

PubMed

Simon, C; Simon, M

1991-01-01

207 clinical isolates from strains of patients from the University Children's Hospital of Kiel were investigated for their in vitro activity with the agar dilution method against flomoxef and cefazolin (alone and partially in combination with vancomycin). Staphylococci were also tested with other cephalosporins (cefoxitin, cefamandole, cefotaxime, cefotetan and latamoxef). Flomoxef and cefazolin always acted more vigorously on staphylococci than the other cephalosporins. Resistance of Staphylococcus aureus strains against flomoxef and cefazolin did not occur but was found in 15 and 5 of 98 Staphylococcus epidermidis strains, respectively. Enterococcus faecalis strains were always resistant against both drugs; Streptococcus faecium strains were only moderately sensitive. Combined testing of flomoxef or cefazolin with vancomycin showed synergism in almost all staphylococcal strains. Synergism was stronger when S. epidermidis strains were only weakly sensitive to or resistant against flomoxef and cefazolin in comparison to highly sensitive strains. Flomoxef (or cefazolin) acted synergistically in combination with vancomycin on E. faecalis and S. faecium with the exception of two strains of E. faecalis which showed an additive effect of both drugs.

Inhibitory and antimicrobial activities of OGTI and HV-BBI peptides, fragments and analogs derived from amphibian skin.

PubMed

Dębowski, Dawid; Łukajtis, Rafał; Łęgowska, Anna; Karna, Natalia; Pikuła, Michał; Wysocka, Magdalena; Maliszewska, Irena; Sieńczyk, Marcin; Lesner, Adam; Rolka, Krzysztof

2012-06-01

A series of linear and cyclic fragments and analogs of two peptides (OGTI and HV-BBI) isolated from skin secretions of frogs were synthesized by the solid-phase method. Their inhibitory activity against several serine proteinases: bovine β-trypsin, bovine α-chymotypsin, human leukocyte elastase and cathepsin G from human neutrophils, was investigated together with evaluation of their antimicrobial activities against Gram-negative bacteria (Escherichia coli) and Gram-positive species isolated from patients (Staphylococcus aureus, Staphylococcus epidermidis, Enterococcus sp., Streptococcus sp.). The cytotoxicity of the selected peptides toward an immortal human skin fibroblast cell line was also determined. Three peptides: HV-BBI, its truncated fragment HV-BBI(3-18) and its analog [Phe(8)]HV-BBI can be considered as bifunctional compounds with inhibitory as well as antibacterial properties. OGTI, although it did not display trypsin inhibitory activity as previously reported in the literature, exerted antimicrobial activity toward S. epidermidis. In addition, under our experimental conditions, this peptide did not show cytotoxicity. Copyright © 2012 Elsevier Inc. All rights reserved.

Comparison of telavancin and vancomycin lock solutions in eradication of biofilm-producing staphylococci and enterococci from central venous catheters.

PubMed

Luther, Megan K; Mermel, Leonard A; LaPlante, Kerry L

2016-03-01

Results of a study of the activity of antibiotic lock solutions of vancomycin and telavancin against biofilm-forming strains of Staphylococcus epidermidis, Enterococcus faecalis, and Staphylococcus aureus are reported. An established in vitro central venous catheter model was used to evaluate lock solutions containing vancomycin (5 mg/mL) or telavancin (5 mg/mL), with and without preservative-containing heparin sodium (with 0.45% benzyl alcohol) 2500 units/mL, heparin, and 0.9% sodium chloride solution. Lock solutions were introduced after 24-hour bacterial growth in catheters incubated at 35 °C. After 72 hours of exposure to the lock solutions, catheters were drained, flushed, and cut into segments for quantification of colony-forming units. Against S. epidermidis, vancomycin and telavancin (with or without heparin) had similar activity. Against E. faecalis, vancomycin alone was more active than telavancin alone (p < 0.01). Against S. aureus, vancomycin plus heparin had activity similar to that of vancomycin alone; both lock agents had greater activity than telavancin (p < 0.02). The addition of heparin was associated with reduced activity of the vancomycin lock solution against S. epidermidis and E. faecalis (p < 0.01). Telavancin activity was not significantly changed with the addition of heparin. In a central venous catheter model, vancomycin and telavancin activity was similar in reducing biofilm-producing S. epidermidis. However, vancomycin was more active than telavancin against E. faecalis and S. aureus. None of the tested agents eradicated biofilm-forming strains. The addition of preservative-containing heparin sodium 2500 units/mL to vancomycin was associated with reduced activity against S. epidermidis and E. faecalis. Copyright © 2016 by the American Society of Health-System Pharmacists, Inc. All rights reserved.

The biocompatability of mesoporous inorganic-organic hybrid resin films with ionic and hydrophilic characteristics.

PubMed

Kim, Gahee; Hong, Lan Young; Jung, Jungwoon; Kim, Dong-Pyo; Kim, Heesoo; Kim, Ik Jung; Kim, Jung Ran; Ree, Moonhor

2010-03-01

New mesoporous silicate-titania resin systems hybridized with 4,5-dihydroxy-m-benzenedisulfonic acid and poly(ethylene glycol)-dimethacrylate component were developed. These inorganic-organic hybrid resins were found to reveal highly controlled ionic and hydrophilic surface with excellent durability and adhesion onto various substrates. The resin films revealed high resistance to nonspecific adsorption of fibrinogen and to adherence by several bacterial pathogens such as Escherichia coli, Staphylococcus aureus, Staphylococcus epidermidis and Enterococcus faecalis. Furthermore, excellent biocompatibility of the developed resins was proved by both HEp-2 cell adhesion in vitro and subcutaneous implantation in mice. The inorganic-organic hybrid resins are strongly promising for biomedical applications including biomedical devices and biosensors. Copyright 2009 Elsevier Ltd. All rights reserved.

[Microbiological characteristics and patterns of resistance in prosthetic joint infections in a referral hospital].

PubMed

Ortega-Peña, Silvestre; Colín-Castro, Claudia; Hernández-Duran, Melissa; López-Jácome, Esaú; Franco-Cendejas, Rafael

2015-01-01

The prosthetic joint infection is the most feared and catastrophic complication for cause severe physical damage to patients and, generates high economic costs. To describe the microbiological characteristics and to determine the resistance pattern in prosthetic joint infections in a reference hospital in Mexico. Patients whose prosthetic devices were withdrawn due to suspicion of septic and aseptic loosening were included. Cultures were performed to identify microorganisms and susceptibility analysis. Of the 111 patients included, 55% were diagnosed with prosthetic joint infection, with the most frequent prosthesis being of the hip (43%). Positive cultures were obtained in 97% of the infected cases, of which 75% were monomicrobial infections. The most frequent bacterial species isolated were: Staphylococcus epidermidis (31%), Enterococcus faecalis (16%), Staphylococcus aureus (13%), and Escherichia coli (8%). The resistance patterns for the Staphylococcus genus were: oxacillin (79%), erythromycin (45%) and ciprofloxacin (37%). Enterococcus faecalis showed a high percentage of resistance to erythromycin and clindamycin (86%), and fluoroquinolones (43%). The large majority (86%) of Escherichia coli were extended spectrum beta-lactamases positive, in addition to having high resistance to fluoroquinolones (86%), trimethoprim/sulfamethoxazole (86%) and gentamicin (72%). The microbiological characteristics found in prosthetic joint infections vary according to the hospitals. In this series, a high proportion of coagulase-negative Staphylococci and Enterococcus spp. were found, as well as a high bacterial resistance. Copyright © 2015 Academia Mexicana de Cirugía A.C. Published by Masson Doyma México S.A. All rights reserved.

Bacterial Diversity of the Gastric Content of Preterm Infants during Their First Month of Life at the Hospital.

PubMed

Moles, Laura; Gómez, Marta; Jiménez, Esther; Bustos, Gerardo; de Andrés, Javier; Melgar, Ana; Escuder, Diana; Fernández, Leónides; Del Campo, Rosa; Rodríguez, Juan Miguel

2017-01-01

Studies focused on the stomach microbiota are relatively scarce, and most of them are focused on the adult population. The aim of this work is to describe the bacterial communities inhabiting the gastric content (GC) of preterm neonates. For that purpose, GC samples were collected weekly from a total of 13 preterm neonates during their first month of life within their hospital stay. Samples were analyzed by using both culture-dependent and -independent techniques. The former allowed the isolation of bacteria belonging mainly to the genera Enterococcus, Staphylococcus, Streptococcus, Serratia, Klebsiella , and Escherichia . The cultured dominant species in the GC samples during all the hospitalization period were Enterococcus faecalis and Staphylococcus epidermidis . Multilocus sequence typing (MLST) analysis revealed the presence of high-risk clonal complexes associated with the hospital environment, which may colonize enteral feeding tubes. Similarly, the 16S rRNA sequencing showed that Streptococcus, Staphylococcus, Lactobacillus, Enterococcus, Corynebacterium , and Propionibacterium were the dominant genera present at 75% of the gastric samples. However, the genera Serratia, Klebsiella , and Streptococcus were the most abundant. Own mother's milk (OMM) and donor milk (DM) were collected after their pass through the external feeding tubes to assess their bacterial content. OMM and DM had a similar bacterial pattern to GC. Based on these data, the GC of preterm neonates is dominated by Proteobacteria and Firmicutes and harbors high-risk bacterial clones, which may colonize enteral feeding tubes, and therefore the feeds that pass through them.

Bacterial Diversity of the Gastric Content of Preterm Infants during Their First Month of Life at the Hospital

PubMed Central

Moles, Laura; Gómez, Marta; Jiménez, Esther; Bustos, Gerardo; de Andrés, Javier; Melgar, Ana; Escuder, Diana; Fernández, Leónides; del Campo, Rosa; Rodríguez, Juan Miguel

2017-01-01

Studies focused on the stomach microbiota are relatively scarce, and most of them are focused on the adult population. The aim of this work is to describe the bacterial communities inhabiting the gastric content (GC) of preterm neonates. For that purpose, GC samples were collected weekly from a total of 13 preterm neonates during their first month of life within their hospital stay. Samples were analyzed by using both culture-dependent and -independent techniques. The former allowed the isolation of bacteria belonging mainly to the genera Enterococcus, Staphylococcus, Streptococcus, Serratia, Klebsiella, and Escherichia. The cultured dominant species in the GC samples during all the hospitalization period were Enterococcus faecalis and Staphylococcus epidermidis. Multilocus sequence typing (MLST) analysis revealed the presence of high-risk clonal complexes associated with the hospital environment, which may colonize enteral feeding tubes. Similarly, the 16S rRNA sequencing showed that Streptococcus, Staphylococcus, Lactobacillus, Enterococcus, Corynebacterium, and Propionibacterium were the dominant genera present at 75% of the gastric samples. However, the genera Serratia, Klebsiella, and Streptococcus were the most abundant. Own mother’s milk (OMM) and donor milk (DM) were collected after their pass through the external feeding tubes to assess their bacterial content. OMM and DM had a similar bacterial pattern to GC. Based on these data, the GC of preterm neonates is dominated by Proteobacteria and Firmicutes and harbors high-risk bacterial clones, which may colonize enteral feeding tubes, and therefore the feeds that pass through them. PMID:28459051

Activity of Fosfomycin- and Daptomycin-Containing Bone Cement on Selected Bacterial Species Being Associated with Orthopedic Infections.

PubMed

Eick, Sigrun; Hofpeter, Kevin; Sculean, Anton; Ender, Claudia; Klimas, Susann; Vogt, Sebastian; Nietzsche, Sandor

2017-01-01

The purpose of this study was to determine activity of fosfomycin/gentamicin and daptomycin/gentamicin-containing PMMA bone-cement against Staphylococcus aureus (MRSA, MSSA), Staphylococcus epidermidis , Enterococcus faecium (VRE), and E. coli (ESBL; only fosfomycin). Test specimens of the bone cement were formed and bacteria in two concentrations were added one time or repeatedly up to 96 h. All fosfomycin-containing cement killed ultimately all MSSA, Staphylococcus epidermidis, and E. coli within 24 h; growth of MRSA was suppressed up to 48 h. Activity of daptomycin-containing cement depended on the concentration; the highest concentrated bone cement used (1.5 g daptomycin/40 g of powder) was active against all one-time added bacteria. When bacteria were added repeatedly to fosfomycin-containing cement, growth was suppressed up to 96 h and that of MRSA and VRE only up to 24 h. The highest concentration of daptomycin suppressed the growth of repeated added bacteria up to 48 h (VRE) until 96 h (MSSA, MRSA). In conclusion, PMMA bone cement with 1.5 g of daptomycin and 0.5 g of gentamicin may be an alternative in treatment of periprosthetic infections caused by Gram-positive bacteria.

Activity of Fosfomycin- and Daptomycin-Containing Bone Cement on Selected Bacterial Species Being Associated with Orthopedic Infections

PubMed Central

Hofpeter, Kevin; Sculean, Anton; Ender, Claudia; Klimas, Susann; Vogt, Sebastian; Nietzsche, Sandor

2017-01-01

The purpose of this study was to determine activity of fosfomycin/gentamicin and daptomycin/gentamicin-containing PMMA bone-cement against Staphylococcus aureus (MRSA, MSSA), Staphylococcus epidermidis, Enterococcus faecium (VRE), and E. coli (ESBL; only fosfomycin). Test specimens of the bone cement were formed and bacteria in two concentrations were added one time or repeatedly up to 96 h. All fosfomycin-containing cement killed ultimately all MSSA, Staphylococcus epidermidis, and E. coli within 24 h; growth of MRSA was suppressed up to 48 h. Activity of daptomycin-containing cement depended on the concentration; the highest concentrated bone cement used (1.5 g daptomycin/40 g of powder) was active against all one-time added bacteria. When bacteria were added repeatedly to fosfomycin-containing cement, growth was suppressed up to 96 h and that of MRSA and VRE only up to 24 h. The highest concentration of daptomycin suppressed the growth of repeated added bacteria up to 48 h (VRE) until 96 h (MSSA, MRSA). In conclusion, PMMA bone cement with 1.5 g of daptomycin and 0.5 g of gentamicin may be an alternative in treatment of periprosthetic infections caused by Gram-positive bacteria. PMID:28484708

Antimicrobial-Resistance Genetic Markers in Potentially Pathogenic Gram Positive Cocci Isolated from Brazilian Soft Cheese.

PubMed

Resende, Juliana Alves; Fontes, Cláudia Oliveira; Ferreira-Machado, Alessandra Barbosa; Nascimento, Thiago César; Silva, Vânia Lúcia; Diniz, Cláudio Galuppo

2018-02-01

Although most Brazilian dairy products meet high technological standards, there are quality issues regarding milk production, which may reduce the final product quality. Several microbial species may contaminate milk during manufacture and handling. If antimicrobial usage remains uncontrolled in dairy cattle, the horizontal transfer of antimicrobial resistance genes in foodstuffs may be of particular concern for both food producers and dairy industry. This study focused on the evaluation of putative Gram positive cocci in Minas cheese and of antimicrobial and biocide resistance genes among the isolated bacteria. Representative samples of 7 different industrially trademarked Minas cheeses (n = 35) were processed for selective culture and isolation of Gram positive cocci. All isolated bacteria were identified by DNA sequencing of the 16S rRNA gene. Antimicrobial resistance genes were screened by PCR. Overall, 208 strains were isolated and identified as follows: Enterococcus faecalis (47.6%), Macrococcus caseolyticus (18.3%), Enterococcus faecium (11.5%), Enterococcus caseliflavus (7.7%), Staphylococcus haemolyticus (7.2%), Staphylococcus aureus (4.3%), Staphylococcus epidermidis (2.9%), and Enterococcus hirae (0.5%). The genetic markers mecA (78.0%) and smr (71.4%) were the most prevalent, but others were also detected, such as blaZ (65.2%), msrA (60.9%), msrB (46.6%), linA (54.7%), and aacA-aphD (47.6%). The occurrence of opportunist pathogenic bacteria harboring antimicrobial resistance markers in the cheese samples are of special concern, since these bacteria are not considered harmful contaminating agents according to the Brazilian sanitary regulations. However, they are potentially pathogenic bacteria and the cheese may be considered a reservoir for antimicrobial resistance genes available for horizontal transfer through the food chain, manufacturing personnel and consumers. © 2018 Institute of Food Technologists®.

Screening Test for Shed Skin Cells by Measuring the Ratio of Human DNA to Staphylococcus epidermidis DNA.

PubMed

Nakanishi, Hiroaki; Ohmori, Takeshi; Hara, Masaaki; Takahashi, Shirushi; Kurosu, Akira; Takada, Aya; Saito, Kazuyuki

2016-05-01

A novel screening method for shed skin cells by detecting Staphylococcus epidermidis (S. epidermidis), which is a resident bacterium on skin, was developed. Staphylococcus epidermidis was detected using real-time PCR. Staphylococcus epidermidis was detected in all 20 human skin surface samples. Although not present in blood and urine samples, S. epidermidis was detected in 6 of 20 saliva samples, and 5 of 18 semen samples. The ratio of human DNA to S. epidermidisDNA was significantly smaller in human skin surface samples than in saliva and semen samples in which S. epidermidis was detected. Therefore, although skin cells could not be identified by detecting only S. epidermidis, they could be distinguished by measuring the S. epidermidis to human DNA ratio. This method could be applied to casework touch samples, which suggests that it is useful for screening whether skin cells and human DNA are present on potential evidentiary touch samples. © 2016 American Academy of Forensic Sciences.

In-vitro screening of Malaysian honey from different floral sources for antibacterial activity on human pathogenic bacteria.

PubMed

Ng, Wen-Jie; Ken, Khai-Wei; Kumar, Roshani-Vijaya; Gunasagaran, Hemamalani; Chandramogan, Vanaysha; Lee, Ying-Yee

2014-01-01

Different researches on therapeutic effects of honey have been conducted in different regions; however the study on the potential antibacterial activity of Malaysian honey is still limited. In this study, antibacterial activities of different monofloral honey samples were tested against several common human pathogenic bacteria. The well-diffusion method, minimum inhibitory concentrations (MIC) and minimum bactericidal concentration (MBC) techniques were employed to investigate the putative antibacterial activity of Malaysian monofloral honey from Koompassia excelsa (Becc.) Taub (Tualang), Melaleuca cajuputi Powell (Gelam) and Durio zibethinus Murr. (Durian). Honey samples were tested against Staphylococcus aureus ATCC6518 and ATCC25923, Staphylococcus epidermidis ATCC12228, Enterococcus faecium LMG16192, Enterococcus faecalis LMG16216 and ATCC29212, Escherichia coli ATCC25922, Salmonella enterica serovar Typhimurium ATCC14028 and Klebsiella pneumoniae ATCC13883. Marked variations were observed in the antibacterial activity of these honey samples. Durian honey failed to produce substantial antibacterial activity, whereas Tualang and Gelam honey showed a spectrum of antibacterial activity with their growth inhibitory effects against all of the tested bacterial species including vancomycin-resistant enterococci (VRE). Present findings suggested Gelam honey possesses highest antibacterial effect among the tested Malaysian honey samples.

Antimicrobial activity of essential oils from Mediterranean aromatic plants against several foodborne and spoilage bacteria.

PubMed

Silva, Nuno; Alves, Sofia; Gonçalves, Alexandre; Amaral, Joana S; Poeta, Patrícia

2013-12-01

The antimicrobial activity of essential oils extracted from a variety of aromatic plants, often used in the Portuguese gastronomy was studied in vitro by the agar diffusion method. The essential oils of thyme, oregano, rosemary, verbena, basil, peppermint, pennyroyal and mint were tested against Gram-positive (Listeria monocytogenes, Clostridium perfringens, Bacillus cereus, Staphylococcus aureus, Enterococcus faecium, Enterococcus faecalis, and Staphylococcus epidermidis) and Gram-negative strains (Salmonella enterica, Escherichia coli, and Pseudomonas aeruginosa). For most essential oils examined, S. aureus, was the most susceptible bacteria, while P. aeruginosa showed, in general, least susceptibility. Among the eight essential oils evaluated, thyme, oregano and pennyroyal oils showed the greatest antimicrobial activity, followed by rosemary, peppermint and verbena, while basil and mint showed the weakest antimicrobial activity. Most of the essential oils considered in this study exhibited a significant inhibitory effect. Thyme oil showed a promising inhibitory activity even at low concentration, thus revealing its potential as a natural preservative in food products against several causal agents of foodborne diseases and food spoilage. In general, the results demonstrate that, besides flavoring the food, the use of aromatic herbs in gastronomy can also contribute to a bacteriostatic effect against pathogens.

An antibacterial ortho-quinone diterpenoid and its derivatives from Caryopteris mongolica.

PubMed

Saruul, Erdenebileg; Murata, Toshihiro; Selenge, Erdenechimeg; Sasaki, Kenroh; Yoshizaki, Fumihiko; Batkhuu, Javzan

2015-06-15

To identify antibacterial components in traditional Mongolian medicinal plant Caryopteris mongolica, an ortho-quinone abietane caryopteron A (1) and three its derivatives caryopteron B-D (2-4) were isolated from the roots of the plant together with three known abietanes demethylcryptojaponol (5), 6α-hydroxydemethyl cryptojaponol (6), and 14-deoxycoleon U (7). The chemical structures of these abietane derivatives were elucidated on the basis of spectroscopic data. Compounds 1-4 had C-13 methylcyclopropane substructures, and 2-4 had a hexanedioic anhydride ring C instead of ortho-quinone in 1. The stereochemistry of these compound was assumed from NOE spectra and ECD Cotton effects. Compounds 1 and 5-7 showed antibacterial activities against the Gram-positive bacteria Staphylococcus aureus, Staphylococcus epidermidis, Enterococcus faecalis, and Micrococcus luteus, being 1 the more potent. Copyright © 2015 Elsevier Ltd. All rights reserved.

Staphylococcus epidermidis and Staphylococcus haemolyticus: Molecular Detection of Cytotoxin and Enterotoxin Genes.

PubMed

Pinheiro, Luiza; Brito, Carla Ivo; de Oliveira, Adilson; Martins, Patrícia Yoshida Faccioli; Pereira, Valéria Cataneli; da Cunha, Maria de Lourdes Ribeiro de Souza

2015-09-14

Although opportunistic pathogens, coagulase-negative staphylococci (CoNS), including Staphylococcus epidermidis and Staphylococcus haemolyticus, have long been regarded as avirulent organisms. The role of toxins in the development of infections caused by CoNS is still controversial. The objective of this study was to characterize the presence of enterotoxin and cytotoxin genes in S. epidermidis and S. haemolyticus isolates obtained from blood cultures. Cytotoxin genes were detected by PCR using novel species-specific primers. Among the 85 S. epidermidis and 84 S. haemolyticus isolates, 95.3% and 79.8%, respectively, carried at least one enterotoxin gene. The most frequent enterotoxin genes were sea (53.3%), seg (64.5%) and sei (67.5%). The seg gene was positively associated with S. epidermidis (p = 0.02), and this species was more toxigenic than S. haemolyticus. The hla/yidD gene was detected in 92.9% of S. epidermidis and the hla gene in 91.7% of S. haemolyticus isolates; hlb was detected in 92.9% of the S. epidermidis isolates and hld in 95.3%. Nosocomial Staphylococcus epidermidis and S. haemolyticus isolates exhibited a high toxigenic potential, mainly producing the non-classical enterotoxins seg and sei. The previously unreported detection of hla/yidD and hlb in S. epidermidis and S. haemolyticus using species-specific primers showed that these hemolysin genes differ between CoNS species and that they are highly frequent in blood culture isolates.

[Yearly changes in antibacterial activities of cefozopran against various clinical isolates between 1996 and 2000--I. Gram-positive bacteria].

PubMed

Suzuki, Yumiko; Nishinari, Chisato; Endo, Harumi; Tamura, Chieko; Jinbo, Keiko; Hiramatsu, Nobuyoshi; Akiyama, Kazumitsu; Koyama, Tsuneo

2002-04-01

The in vitro antibacterial activities of cefozopran (CZOP), an agent of cephems, against various clinical isolates obtained between 1996 and 2000 were yearly evaluated and compared with those of other cephems, oxacephems, carbapenems, and penicillins. Fifteen species, 1,062 strains, of Gram-positive bacteria were isolated from the clinical materials annually collected from January to December, and consisted of methicillin-susceptible Staphylococcus aureus (MSSA; n = 127), methicillin-resistant Staphylococcus aureus (MRSA; n = 123), Staphylococcus epidermidis (n = 104), Staphylococcus haemolyticus (n = 58), Streptococcus pyogenes (n = 100), Streptococcus agalactiae (n = 50), Streptococcus pneumoniae (n = 125), Enterococcus faecalis (n = 150), Enterococcus faecium (n = 50), Enterococcus avium (n = 50), and Peptostreptococcus spp. (P. anaerobius, P. asaccharolyticus, P. magnus, P. micros, P. prevotii; n = 125). CZOP possessed stable antibacterial activities against all strains tested throughout 5 years. The MIC90 of CZOP against MRSA and S. haemolyticus tended to decrease while against S. pneumoniae and Peptostreptococcus spp., tended to increase year by year. However, the MIC90 just changed a little and were consistent with the results from the studies performed until the new drug application approval. Increases in the MIC90 against S. pneumoniae were also observed with cefpirome (CPR), cefepime (CFPM), flomoxef (FMOX), sulbactam/cefoperazone (SBT/CPZ), and imipenem (IPM). Increases in the MIC90 against Peptostreptococcus spp. were also observed with ceftazidime (CAZ), CPR, CFPM, FMOX, SBT/CPZ, and IPM. The decreases in the sensitivities were not always considered to depend upon generation of resistant bacteria because the annual MIC range of each antibacterial agent was almost generally wide every year and the annual sensitivity of each strain to the agents extremely varied. In conclusion, the annual antibacterial activities of CZOP against the Gram-positive bacteria did not considerably change. It, therefore, was suggested that CZOP had maintained high antibacterial activity during 5 years of post-marketing.

Physicochemical and biological properties of oxovanadium(IV), cobalt(II) and nickel(II) complexes with oxydiacetate anions.

PubMed

Wyrzykowski, Dariusz; Kloska, Anna; Pranczk, Joanna; Szczepańska, Aneta; Tesmar, Aleksandra; Jacewicz, Dagmara; Pilarski, Bogusław; Chmurzyński, Lech

2015-03-01

The potentiometric and conductometric titration methods have been used to characterize the stability of series of VO(IV)-, Co(II)- and Ni(II)-oxydiacetato complexes in DMSO-water solutions containing 0-50 % (v/v) DMSO. The influence of DMSO as a co-solvent on the stability of the complexes as well as the oxydiacetic acid was evaluated. Furthermore, the reactivity of the complexes towards superoxide free radicals was assessed by employing the nitro blue tetrazolium (NBT) assay. The biological properties of the complexes were investigated in relation to their cytoprotective activity against the oxidative damage generated exogenously by using hydrogen peroxide in the Human Dermal Fibroblasts adult (HDFa) cell line as well as to their antimicrobial activity against the bacteria (Bacillus subtilis, Escherichia coli, Enterococcus faecalis, Pseudomonas aeruginosa, Staphylococcus aureus, Staphylococcus epidermidis). The relationship between physicochemical and biological properties of the complexes was discussed.

Staphylococcus epidermidis and Staphylococcus haemolyticus: Molecular Detection of Cytotoxin and Enterotoxin Genes

PubMed Central

Pinheiro, Luiza; Ivo Brito, Carla; de Oliveira, Adilson; Yoshida Faccioli Martins, Patrícia; Cataneli Pereira, Valéria; Ribeiro de Souza da Cunha, Maria de Lourdes

2015-01-01

Although opportunistic pathogens, coagulase-negative staphylococci (CoNS), including Staphylococcus epidermidis and Staphylococcus haemolyticus, have long been regarded as avirulent organisms. The role of toxins in the development of infections caused by CoNS is still controversial. The objective of this study was to characterize the presence of enterotoxin and cytotoxin genes in S. epidermidis and S. haemolyticus isolates obtained from blood cultures. Cytotoxin genes were detected by PCR using novel species-specific primers. Among the 85 S. epidermidis and 84 S. haemolyticus isolates, 95.3% and 79.8%, respectively, carried at least one enterotoxin gene. The most frequent enterotoxin genes were sea (53.3%), seg (64.5%) and sei (67.5%). The seg gene was positively associated with S. epidermidis (p = 0.02), and this species was more toxigenic than S. haemolyticus. The hla/yidD gene was detected in 92.9% of S. epidermidis and the hla gene in 91.7% of S. haemolyticus isolates; hlb was detected in 92.9% of the S. epidermidis isolates and hld in 95.3%. Nosocomial Staphylococcus epidermidis and S. haemolyticus isolates exhibited a high toxigenic potential, mainly containing the non-classical enterotoxin genes seg and sei. The previously unreported detection of hla/yidD and hlb in S. epidermidis and S. haemolyticus using species-specific primers showed that these hemolysin genes differ between CoNS species and that they are highly frequent in blood culture isolates. PMID:26389954

[Post-marketing surveillance of antibacterial activities of cefozopran against various clinical isolates--I. Gram-positive bacteria].

PubMed

Igari, Jun; Oguri, Toyoko; Hiramatsu, Nobuyoshi; Akiyama, Kazumitsu; Koyama, Tsuneo

2002-02-01

As a post-marketing surveillance, the in vitro antibacterial activities of cefozopran (CZOP), an agent of cephems, against various clinical isolates were yearly evaluated and compared with those of other cephems, oxacephems, penicillins, and carbapenems. Changes in the bacterial sensitivity for CZOP were also evaluated with the resistance ratio calculated with breakpoint MIC. Sixteen species (1,913 strains) of Gram-positive bacteria were isolated from the clinical materials annually collected from 1996 to 2000, and consisted of methicillin-susceptible Staphylococcus aureus (MSSA; n = 178), methicillin-resistant S. aureus (MRSA; n = 199), methicillin-susceptible Staphylococcus epidermidis (MSSE; n = 98), methicillin-resistant S. epidermidis (MRSE; n = 164), Staphylococcus haemolyticus (n = 72), Staphylococcus saprophyticus (n = 28), Enterococcus faecalis (n = 206), Enterococcus faecium (n = 91), Enterococcus avium (n = 72), Streptococcus pyogenes (n = 133), Streptococcus agalactiae (n = 138), penicillin-susceptible Streptococcus pneumoniae (PSSP; n = 133), penicillin-intermediate resistant S. pneumoniae (PISP; n = 100), penicillin-resistant S. pneumoniae (PRSP; n = 29), Streptococcus milleri group (n = 135) and Peptostreptococcus spp. (n = 137). CZOP possessed comparable antibacterial activities against MSSA and MSSE to other cephems, and was also effective on MRSE but not on MRSA. An antibacterial activity of CZOP against S. saprophyticus was comparable to or higher than other cephems. CZOP, however, did not indicate an antibacterial activity against S. haemolyticus, just like other cephems. An antibacterial activity of CZOP against E. faecalis was comparable to cefpirome (CPR) and higher than other cephems. No antibacterial activity of CZOP against E. faecium and E. avium was observed, just like other drugs. An antibacterial activity of CZOP against S. pyogenes was as potent as that of cefotiam (CTM), cefepime (CFPM) and CPR, and that against S. agalactiae was also preferable. CZOP and other cephems also had a preferable antibacterial activity against S. milleri group that was most sensitive to benzylpenicillin. An antibacterial activity of CZOP against Peptostreptococcus spp. was preferable but weaker than that of cefazolin, CTM and cefmetazole. The resistance ratio estimated with breakpoint MIC of CZOP was 96.5% in MRSA, 93.1% in PRSP, 60.0% in PISP, 40.3% in S. haemolyticus, 22.3% in E. faecalis, and 15.9% in MRSE. Those resistance ratios were similar to those for CFPM, but E. faecalis showed 90.8% resistance for CFPM. The difference in the resistance ratio of E. faecalis demonstrated that CZOP successfully maintained its antibacterial activity against this species. In conclusion, no remarkable annual change in the antibacterial activities of CZOP against the Gram-positive bacteria was observed. The sensitivities of PISP and PRSP to CZOP, however, was suggested to be decreasing.

Clinical significance of the isolation of Staphylococcus epidermidis from bone biopsy in diabetic foot osteomyelitis.

PubMed

Aragón-Sánchez, Javier; Lázaro-Martínez, Jose Luis; Hernández-Herrero, María José; Quintana-Marrero, Yurena; Cabrera-Galván, Juan J

2010-01-01

Coagulase-negative staphylococci are considered as microorganisms with little virulence and usually as contaminants. In order to establish the role of Staphylococcus epidermidis as a pathogen in diabetic foot osteomyelitis, in addition to the isolation of the sole bacterium from the bone it will be necessary to demonstrate the histopathological changes caused by the infection. A consecutive series of 222 diabetic patients with foot osteomyelitis treated surgically in the Diabetic Foot Unit at La Paloma Hospital (Las Palmas de Gran Canaria, Canary Islands, Spain) between 1 October 2002 and 31 October 2008. From the entire series including 213 bone cultures with 241 isolated organisms, we have analyzed only the 139 cases where Staphylococci were found. We analyzed several variables between the two groups: Staphylococcus aureus versus Staphylococcus epidermidis. Of the 134 patients included in this study, Staphlylococcus epidermidis was found as the sole bacterium isolated in 11 cases and accompanied by other bacteria in 12 cases. Staphlylococcus aureus was found as the sole bacterium isolated in 72 cases and accompanied by other bacteria in 39 cases. Histopathological changes were found in the cases of osteomyelitis where Staphylococcus epidermidis was the sole bacterium isolated. Acute osteomyelitis was found to a lesser extent when Staphylococcus epidermidis was the sole bacterium isolated but without significant differences with the cases where Staphylococcus aureus was the sole bacterium isolated. Staphylococcus epidermidis should be considered as a real pathogen, not only a contaminant, in diabetic patients with foot osteomyelitis when the bacterium is isolated from the bone. No differences in the outcomes of surgical treatment have been found with cases which Staphlylococcus aureus was isolated.

Clinical significance of the isolation of Staphylococcus epidermidis from bone biopsy in diabetic foot osteomyelitis

PubMed Central

Aragón-Sánchez, Javier; Lázaro-Martínez, Jose Luis; Hernández-Herrero, María José; Quintana-Marrero, Yurena; Cabrera-Galván, Juan J.

2010-01-01

Introduction Coagulase-negative staphylococci are considered as microorganisms with little virulence and usually as contaminants. In order to establish the role of Staphylococcus epidermidis as a pathogen in diabetic foot osteomyelitis, in addition to the isolation of the sole bacterium from the bone it will be necessary to demonstrate the histopathological changes caused by the infection. Methods A consecutive series of 222 diabetic patients with foot osteomyelitis treated surgically in the Diabetic Foot Unit at La Paloma Hospital (Las Palmas de Gran Canaria, Canary Islands, Spain) between 1 October 2002 and 31 October 2008. From the entire series including 213 bone cultures with 241 isolated organisms, we have analyzed only the 139 cases where Staphylococci were found. We analyzed several variables between the two groups: Staphylococcus aureus versus Staphylococcus epidermidis. Results Of the 134 patients included in this study, Staphlylococcus epidermidis was found as the sole bacterium isolated in 11 cases and accompanied by other bacteria in 12 cases. Staphlylococcus aureus was found as the sole bacterium isolated in 72 cases and accompanied by other bacteria in 39 cases. Histopathological changes were found in the cases of osteomyelitis where Staphylococcus epidermidis was the sole bacterium isolated. Acute osteomyelitis was found to a lesser extent when Staphylococcus epidermidis was the sole bacterium isolated but without significant differences with the cases where Staphylococcus aureus was the sole bacterium isolated. Conclusion Staphylococcus epidermidis should be considered as a real pathogen, not only a contaminant, in diabetic patients with foot osteomyelitis when the bacterium is isolated from the bone. No differences in the outcomes of surgical treatment have been found with cases which Staphlylococcus aureus was isolated. PMID:22396808

Comparison of the gentamicin resistance transposon Tn5281 with regions encoding gentamicin resistance in Enterococcus faecalis isolates from diverse geographic locations.

PubMed Central

Hodel-Christian, S L; Murray, B E

1992-01-01

The genetic determinant encoding gentamicin resistance (Gmr) on the beta-lactamase encoding plasmid pBEM10 of Enterococcus faecalis HH22 is carried on a transposon, termed Tn5281, that is highly related to the staphylococcal Gmr transposons Tn4001 found in Australian isolates of Staphylococcus aureus and Tn4031 found in United States isolates of Staphylococcus epidermidis. We have now studied plasmid DNA from Gmr strains of E. faecalis isolated from diverse geographical locations (Houston, Pennsylvania, Thailand, and Chile) by using restriction endonuclease analysis and DNA-DNA hybridization to determine whether other Gmr E. faecalis carry Tn5281 or a similar type of element. We also compared these enterococci to several United States isolates of Staphylococcus aureus with nonmobile Gmr determinants. Three E. faecalis isolates (from Houston and Chile) carried Tn5281-like elements, whereas two isolates (from Houston and Pennsylvania) had restriction endonuclease and DNA-DNA hybridization patterns more similar to those of the Tn4001-IS257 hybrid found in the nonmobile Gmr determinants in United States isolates of S. aureus. A strain from Thailand had a third pattern unrelated to either Tn5281 or the nonmobile Gmr determinants present in United States isolates of S. aureus. Our results demonstrate that there is both similarity and diversity between the Gmr determinant of strains of E. faecalis isolated in diverse geographic locations. Images PMID:1332593

Staphylococcus lugdunensis, a serious pathogen in periprosthetic joint infections: comparison to Staphylococcus aureus and Staphylococcus epidermidis.

PubMed

Lourtet-Hascoët, J; Bicart-See, A; Félicé, M P; Giordano, G; Bonnet, E

2016-10-01

The aim of this study was to assess the characteristics of periprosthetic joint infection (PJI) due to Staphylococcus lugdunensis and to compare these to the characteristics of PJI due to Staphylococcus aureus and Staphylococcus epidermidis. A retrospective multicentre study including all consecutive cases of S. lugdunensis PJI (2000-2014) was performed. Eighty-eight cases of staphylococcal PJI were recorded: 28 due to S. lugdunensis, 30 to S. aureus, and 30 to S. epidermidis, as identified by Vitek 2 or API Staph (bioMérieux). Clinical symptoms were more often reported in the S. lugdunensis group, and the median delay between surgery and infection was shorter for the S. lugdunensis group than for the S. aureus and S. epidermidis groups. Regarding antibiotic susceptibility, the S. lugdunensis strains were susceptible to antibiotics and 61% of the patients could be treated with levofloxacin + rifampicin. The outcome of the PJI was favourable for 89% of patients with S. lugdunensis, 83% with S. aureus, and 97% with S. epidermidis. S. lugdunensis is an emerging pathogen with a pathogenicity quite similar to that of S. aureus. This coagulase-negative Staphylococcus must be identified precisely in PJI, in order to select the appropriate surgical treatment and antibiotics . Copyright © 2016 The Author(s). Published by Elsevier Ltd.. All rights reserved.

Infectious Risk Assessment of Unsafe Handling Practices and Management of Clinical Solid Waste

PubMed Central

Hossain, Md. Sohrab; Rahman, Nik Norulaini Nik Ab; Balakrishnan, Venugopal; Puvanesuaran, Vignesh R.; Sarker, Md. Zaidul Islam; Kadir, Mohd Omar Ab

2013-01-01

The present study was undertaken to determine the bacterial agents present in various clinical solid wastes, general waste and clinical sharp waste. The waste was collected from different wards/units in a healthcare facility in Penang Island, Malaysia. The presence of bacterial agents in clinical and general waste was determined using the conventional bacteria identification methods. Several pathogenic bacteria including opportunistic bacterial agent such as Pseudomonas aeruginosa, Salmonella spp., Klebsiella pneumoniae, Serratia marcescens, Acinetobacter baumannii, Staphylococcus aureus, Staphylococcus epidermidis, Enterococcus faecalis, Streptococcus pyogenes were detected in clinical solid wastes. The presence of specific pathogenic bacterial strains in clinical sharp waste was determined using 16s rDNA analysis. In this study, several nosocomial pathogenic bacteria strains of Escherichia coli, Klebsiella pneumoniae, Proteus mirabilis, Lysinibacillus sphaericus, Serratia marcescens, and Staphylococcus aureus were detected in clinical sharp waste. The present study suggests that waste generated from healthcare facilities should be sterilized at the point of generation in order to eliminate nosocomial infections from the general waste or either of the clinical wastes. PMID:23435587

Isolation and purification of enterocin E-760 with broad antimicrobial activity against gram-positive and gram-negative bacteria.

PubMed

Line, J E; Svetoch, E A; Eruslanov, B V; Perelygin, V V; Mitsevich, E V; Mitsevich, I P; Levchuk, V P; Svetoch, O E; Seal, B S; Siragusa, G R; Stern, N J

2008-03-01

Strain NRRL B-30745, isolated from chicken ceca and identified as Enterococcus durans, Enterococcus faecium, or Enterococcus hirae, was initially identified as antagonistic to Campylobacter jejuni. The isolate produced a 5,362-Da bacteriocin (enterocin) that inhibits the growth of Salmonella enterica serovar Enteritidis, S. enterica serovar Choleraesuis, S. enterica serovar Typhimurium, S. enterica serovar Gallinarum, Escherichia coli O157:H7, Yersinia enterocolitica, Citrobacter freundii, Klebsiella pneumoniae, Shigella dysenteriae, Pseudomonas aeruginosa, Proteus mirabilis, Morganella morganii, Staphylococcus aureus, Staphylococcus epidermidis, Listeria monocytogenes, Campylobacter jejuni, and 20 other Campylobacter species isolates. The enterocin, E-760, was isolated and purified by cation-exchange and hydrophobic-interaction chromatographies. The proteinaceous nature of purified enterocin E-760 was demonstrated upon treatment with various proteolytic enzymes. Specifically, the antimicrobial peptide was found to be sensitive to beta-chymotrypsin, proteinase K, and papain, while it was resistant to lysozyme and lipase. The enterocin demonstrated thermostability by retaining activity after 5 min at 100 degrees C and was stable at pH values between 5.0 and 8.7. However, activity was lost below pH 3.0 and above pH 9.5. Administration of enterocin E-760-treated feed significantly (P < 0.05) reduced the colonization of young broiler chicks experimentally challenged and colonized with two strains of C. jejuni by more than 8 log(10) CFU. Enterocin E-760 also significantly (P < 0.05) reduced the colonization of naturally acquired Campylobacter species in market age broiler chickens when administered in treated feed 4 days prior to analysis.

Differentiation between Staphylococcus aureus and Staphylococcus epidermidis strains using Raman spectroscopy.

PubMed

Rebrošová, Katarína; Šiler, Martin; Samek, Ota; Růžička, Filip; Bernatová, Silvie; Ježek, Jan; Zemánek, Pavel; Holá, Veronika

2017-08-01

Raman spectroscopy is an analytical method with a broad range of applications across multiple scientific fields. We report on a possibility to differentiate between two important Gram-positive species commonly found in clinical material - Staphylococcus aureus and Staphylococcus epidermidis - using this rapid noninvasive technique. For this, we tested 87 strains, 41 of S. aureus and 46 of S. epidermidis, directly from colonies grown on a Mueller-Hinton agar plate using Raman spectroscopy. The method paves a way for separation of these two species even on high number of samples and therefore, it can be potentially used in clinical diagnostics.

Enzymatic Detachment of Staphylococcus epidermidis Biofilms

PubMed Central

Kaplan, Jeffrey B.; Ragunath, Chandran; Velliyagounder, Kabilan; Fine, Daniel H.; Ramasubbu, Narayanan

2004-01-01

The gram-positive bacterium Staphylococcus epidermidis is the most common cause of infections associated with catheters and other indwelling medical devices. S. epidermidis produces an extracellular slime that enables it to form adherent biofilms on plastic surfaces. We found that a biofilm-releasing enzyme produced by the gram-negative periodontal pathogen Actinobacillus actinomycetemcomitans rapidly and efficiently removed S. epidermidis biofilms from plastic surfaces. The enzyme worked by releasing extracellular slime from S. epidermidis cells. Precoating surfaces with the enzyme prevented S. epidermidis biofilm formation. Our findings demonstrate that biofilm-releasing enzymes can exhibit broad-spectrum activity and that these enzymes may be useful as antibiofilm agents. PMID:15215120

The use of nucleosides and arginine as alternative energy sources by coagulase-negative staphylococci in view of meat fermentation.

PubMed

Janssens, M; Van der Mijnsbrugge, A; Sánchez Mainar, M; Balzarini, T; De Vuyst, L; Leroy, F

2014-05-01

The ability of coagulase-negative staphylococci (CNS) to use alternative energy sources in meat may partially explain their occurrence in fermented meats. Of 61 CNS strains tested, all metabolized adenosine and inosine in a meat simulation medium (MSM). The ability to catabolize arginine via the arginine deiminase (ADI) pathway varied between strains. All tested strains of Staphylococcus carnosus and Staphylococcus epidermidis possessed an arcA gene and showed ADI activity, whereas other species, such as Staphylococcus equorum and Staphylococcus succinus, did not. Arginine catabolic mobile elements (ACME), as in the positive control S. epidermidis ATCC 12228, were uncommon and only found in Staphylococcus xylosus 3PA6 (sausage isolate) and Staphylococcus chromogenes G222 (teat apex isolate). Monoculture experiments were performed in MSM with S. carnosus 833 and SS3-4, S. xylosus G211, and S. epidermidis ATCC 12228 and 2S7-4. At all pH values tested (5.3, 5.8, and 6.5), the strains of S. carnosus catabolized arginine faster than the strains of S. xylosus and S. epidermidis. Only at pH 6.5 could a low ADI activity be found for S. xylosus G211. Increased ADI activity occurred in the case of the ACME-positive S. epidermidis ATCC 12228, when compared to the ACME-negative S. epidermidis 2S7-4. Copyright © 2013 Elsevier Ltd. All rights reserved.

Effect of Hydroxyurea on Staphylococcus epidermidis and Micrococcus lysodeikticus: Thickening of the Cell Wall

PubMed Central

Feiner, Rose R.; Coward, Joe E.; Rosenkranz, Herbert S.

1973-01-01

Hydroxyurea-sensitive strains of Staphylococcus epidermidis and Micrococcus lysodeikticus showed marked thickening of cell walls and reduction in deoxyribonucleic acid synthesis when grown in the presence of hydroxyurea. Images PMID:4790602

[Post-marketing surveillance of antibacterial activities of cefozopran against various clinical isolates--I. Gram-positive bacteria].

PubMed

Igari, Jun; Oguri, Toyoko; Hiramatsu, Nobuyoshi; Akiyama, Kazumitsu; Koyama, Tsuneo

2003-10-01

As a post-marketing surveillance, the in vitro antibacterial activities of cefozopran (CZOP), an agent of cephems, against various clinical isolates were yearly evaluated and compared with those of other cephems, oxacephems, penicillins, and carbapenems. Changes in the bacterial susceptibility for CZOP were also evaluated with the resistance ratio calculated with breakpoint MIC. Sixteen species (2,363 strains) of Gram-positive bacteria were isolated from the clinical materials annually collected from 1996 to 2001, and consisted of methicillin-susceptible Staphylococcus aureus (MSSA), methicillin-resistant Staphylococcus aureus (MRSA), methicillin-susceptible Staphylococcus epidermidis (MSSE), methicillin-resistant Staphylococcus epidermidis (MRSE), Staphylococcus haemolyticus, Staphylococcus saprophyticus, Enterococcus faecalis, Enterococcus faecium, Enterococcus avium, Streptococcus pyogenes, Streptococcus agalactiae, penicillin-susceptible Streptococcus pneumoniae (PSSP), penicillin-intermediate resistant S. pneumoniae (PISP), penicillin-resistant S. pneumoniae (PRSP), Streptococcus milleri group and Peptostreptococcus spp. The antibacterial activity of CZOP either against MSSA or MSSE was preferable (MIC90: 2 or 0.5 micrograms/mL) and comparable to those of other cephems. CZOP was also effective on MRSE (MIC90: 16 micrograms/mL) but not on MRSA. CZOP and other cephems had low antibacterial activity against S. haemolyticus (MIC90: 64 micrograms/mL). The antibacterial activity of CZOP against S. saprophyticus was comparable to or higher than those of other cephems, but the MIC90 of CZOP in 2001 was higher than those in 1996-2000 (32 vs 1-2 micrograms/mL). The antibacterial activity of CZOP against E. faecalis was comparable to that of cefpirome (CPR; MIC90: 16 micrograms/mL) and higher than those of other cephems. No antibacterial activity of CZOP against E. faecium and E. avium was observed, like other drugs. The antibacterial activity of CZOP against S. pyogenes was as potent as those of cefotiam and CPR (MIC90: < or = 0.063 microgram/mL), and, against S. agalactiae, was also preferable (MIC90: 0.125 microgram/mL). CZOP indicated preferable antibacterial activity either against PSSP, PISP, or PRSP (MIC90: 0.25, 1, or 2 micrograms/mL). The antibacterial activity of CZOP against S. milleri group was also preferable, but the MIC90 of CZOP in 2001 was higher than those in 1996-2000 (4 vs 0.5 micrograms/mL). The antibacterial activity of CZOP against Peptostreptococcus spp. was preferable but weaker than those of cefazolin and cefmetazole. The resistance ratio estimated from breakpoint MIC of CZOP was 95.9% in MRSA, 93.5% in PRSP, 63.3% in PISP, 35.8% in S. haemolyticus, 27.9% in E. faecalis, and 13.3% MRSE. Those resistance ratios were comparable to those for cefepime (CFPM), but E. faecalis showed 91.2% for CFPM. The difference in the resistance ratio of E. faecalis demonstrated that CZOP successfully maintained its antibacterial activity against these species. In correlation of drug susceptibility, 40.3% of PRSP was not inhibited at breakpoint MIC either CZOP or CFPM while 69.2% at breakpoint MIC either CZOP or ceftazidime. In conclusion, the antibacterial activities of CZOP against the Gram-positive bacteria obtained from the 6-year duration study were consistent with the results from the studies performed until the new drug application approval. A decline in the sensitivities of S. saprophyticus, S. milleri group, PISP, and PRSP to CZOP, however, was suggested.

Comparative study on nutrient depletion-induced lipidome adaptations in Staphylococcus haemolyticus and Staphylococcus epidermidis.

PubMed

Luo, Yu; Javed, Muhammad Afzal; Deneer, Harry

2018-02-05

Staphylococcus species are emerging opportunistic pathogens that cause outbreaks of hospital and community-acquired infections. Some of these bacteria such as methicillin-resistant Staphylococcus aureus (MRSA) are difficult to treat due to their resistance to multiple antibiotics. We carried out a comparative study on the lipidome adaptations in response to starvation in the two most common coagulase-negative Staphylococcus species: a S. epidermidis strain sensitive to ampicillin and erythromycin and a S. haemolyticus strain resistant to both. The predominant fatty acid composition in glycerolipids was (17:0-15:0) in both bacteria. During the exponential phase, the two bacterial lipidomes were similar. Both were dominated by diacylglycerol (DAG), phosphatidylglycerol (PG), lysyl-phosphatidylglycerol (Lysyl-PG) and Diglucosyl-diacylglycerol (DGDG). Alanyl-PG was detected in small amounts in both bacterial lipids. N-succinyl-lysyl-PG was detected only in S. haemolyticus, while lysyl-DAG only in S. epidermidis. As the two bacteria entered stationary phase, both lipidomes became essentially nitrogen-free. Both bacteria accumulated large amounts of free fatty acids. Strikingly, the lipidome of S. epidermidis became dominated by cardiolipin (CL), while that of S. haemolyticus was simplified to DGDG and PG. The S. epidermidis strain also produced acyl-phosphatidylglycerol (APG) in the stationary phase.

Maggot excretions inhibit biofilm formation on biomaterials.

PubMed

Cazander, Gwendolyn; van de Veerdonk, Mariëlle C; Vandenbroucke-Grauls, Christina M J E; Schreurs, Marco W J; Jukema, Gerrolt N

2010-10-01

Biofilm-associated infections in trauma surgery are difficult to treat with conventional therapies. Therefore, it is important to develop new treatment modalities. Maggots in captured bags, which are permeable for larval excretions/secretions, aid in healing severe, infected wounds, suspect for biofilm formation. Therefore we presumed maggot excretions/secretions would reduce biofilm formation. We studied biofilm formation of Staphylococcus aureus, Staphylococcus epidermidis, Klebsiella oxytoca, Enterococcus faecalis, and Enterobacter cloacae on polyethylene, titanium, and stainless steel. We compared the quantities of biofilm formation between the bacterial species on the various biomaterials and the quantity of biofilm formation after various incubation times. Maggot excretions/secretions were added to existing biofilms to examine their effect. Comb-like models of the biomaterials, made to fit in a 96-well microtiter plate, were incubated with bacterial suspension. The formed biofilms were stained in crystal violet, which was eluted in ethanol. The optical density (at 595 nm) of the eluate was determined to quantify biofilm formation. Maggot excretions/secretions were pipetted in different concentrations to (nonstained) 7-day-old biofilms, incubated 24 hours, and finally measured. The strongest biofilms were formed by S. aureus and S. epidermidis on polyethylene and the weakest on titanium. The highest quantity of biofilm formation was reached within 7 days for both bacteria. The presence of excretions/secretions reduced biofilm formation on all biomaterials. A maximum of 92% of biofilm reduction was measured. Our observations suggest maggot excretions/secretions decrease biofilm formation and could provide a new treatment for biofilm formation on infected biomaterials.

Antimicrobial activity of traditional medicinal plants from Ankober District, North Shewa Zone, Amhara Region, Ethiopia.

PubMed

Lulekal, E; Rondevaldova, J; Bernaskova, E; Cepkova, J; Asfaw, Z; Kelbessa, E; Kokoska, L; Van Damme, P

2014-05-01

Traditional medicinal plants have long been used in Ethiopia to treat human and livestock ailments. Despite a well-documented rich tradition of medicinal plant use in the country, their direct antimicrobial effects are still poorly known. To investigate the antimicrobial activity of 19 medicinal plant species that were selected based on the ethnobotanical information on their traditional use to treat infectious diseases in Ankober District. About 23 different ethanol extracts of plants obtained by maceration of various parts of 19 medicinal plant species were studied for potential antimicrobial activity using a broth microdilution method against Bacillus cereus, Bacteroides fragilis, Candida albicans, Clostridium perfringens, Enterococcus faecalis, Escherichia coli, Listeria monocytogenes, Pseudomonas aeruginosa, Salmonella enteritidis, Staphylococcus aureus, Staphylococcus epidermidis, and Streptococcus pyogenes. Plant extracts from Embelia schimperi Vatke (Myrsinaceae) showed the strongest antibacterial activity with a minimum inhibitory concentration (MIC) value of 64 µg/ml against B. cereus, L. monocytogenes, and S. pyogenes. Growth inhibitory activities were also observed for extracts of Ocimum lamiifolium Hochst. (Lamiaceae) against S. pyogenes, and those of Rubus steudneri Schweinf. (Rosaceae) against S. epidermidis at an MIC value of 128 µg/ml. Generally, 74% of ethanol extracts (17 extracts) showed antimicrobial activity against one or more of the microbial strains tested at an MIC value of 512 µg/ml or below. Results confirm the antimicrobial role of traditional medicinal plants of Ankober and warrant further investigations on promising medicinal plant species so as to isolate and characterise chemicals responsible for the observed strong antimicrobial activities.

Pathogens Present in Acute Mangled Extremities From Afghanistan and Subsequent Pathogen Recovery

DTIC Science & Technology

2015-01-01

methicillin - resistant Staphylococcus aureus or vancomycin- resistant Enterococcus. Most wounds were colonized with low-virulence...there were no methicillin - resistant Staphylococcus aureus or vancomycin- resistant Enterococcus. Although Enterococcus was recovered at Role 3 and 4 in 9...available for furthermicrobiological analysis in this study.MDRwas defined asmethicillin- resistant Staphylococcus aureus , vancomycin- resistant

Impact of Staphylococcus epidermidis lysates on middle ear epithelial proinflammatory and mucogenic response.

PubMed

Val, Stéphanie; Mubeen, Humaira; Tomney, Amarel; Chen, Saisai; Preciado, Diego

2015-02-01

Chronic otitis media with effusion (COME) develops after sustained inflammation and is characterized by secretory middle ear epithelial metaplasia and effusion, most frequently mucoid. Staphylococcus epidermidis, typically considered a commensal organism, is very frequently recovered in chronic middle ear fluid and in middle ear biofilms. Although it has been shown to drive inflammation in sinonasal epithelium, the impact of S. epidermidis on COME is markedly understudied. The goal of this study was to examine the in vitro effects of S. epidermidis lysates on murine and human middle ear epithelial cells. Staphylococcus epidermidis lysates were generated and used to stimulate submerged and differentiated human and murine epithelial cells (MEECs) for 24 to 48 hours. Quantitative real time-polymerase chain reaction, Western blot, enzyme-linked immunosorbent assay, and immunocytochemistry techniques were performed to interrogate the mucin gene MUC5AC and MUC5B expression and protein production, chemokine response, as well as NF-κB activation. Luciferase reporter assays were performed to further evaluate nuclear factor κB (NF-κB) activation and query specific promoter responses after S. epidermidis exposure. Staphylococcus epidermidis induced a time- and dose-dependent MUC5AC and MUC5B overexpression along with a parallel overexpression of Cxcl2 in mouse MEEC and IL-8 in human MEEC. Further investigations in mMEEC showed a 1.3 to 1.5 induction of the MUC5AC and MUC5B promoters. As potential mechanisms for these responses, induction of an oxidative stress marker, along with early nuclear translocation and activation of NF-κB, was found. Finally, chronic exposure induced marked epithelial thickening of cells differentiated at the air liquid interface. Staphylococcus epidermidis lysates activate a proinflammatory response in MEEC, including mucin gene expression and protein production. Although typically considered a nonpathogenic commensal organism in the ear, these results suggest that they may play a role in the perpetuation of an inflammatory and mucogenic response in COME.

Susceptibility Profile of Staphylococcus epidermidis and Staphylococcus haemolyticus Isolated from Blood Cultures to Vancomycin and Novel Antimicrobial Drugs over a Period of 12 Years.

PubMed

Pinheiro, Luiza; Brito, Carla Ivo; Pereira, Valéria Cataneli; Oliveira, Adilson; Bartolomeu, Ariane Rocha; Camargo, Carlos Henrique; Cunha, Maria Lourdes Ribeiro Souza

2016-06-01

The aim of this study was to evaluate the antimicrobial susceptibility profile of 85 Staphylococcus epidermidis and 84 Staphylococcus haemolyticus strains isolated from blood cultures to oxacillin, vancomycin, tigecycline, linezolid, daptomycin, and quinupristin/dalfopristin over a period of 12 years. S. epidermidis and S. haemolyticus isolated from blood cultures of inpatients, attended at a teaching hospital, were analyzed for the presence of the mecA gene and by SCCmec typing. The minimum inhibitory concentration (MIC) values of tigecycline, linezolid, daptomycin, quinupristin/dalfopristin, and vancomycin were determined. Isolates exhibiting vancomycin MICs of ≥2 μg/ml were typed by pulsed-field gel electrophoresis (PFGE). The rate of mecA positivity was 92.9% and 100% in S. epidermidis and S. haemolyticus, respectively. The most frequent SCCmec types were type III (53.2%) in S. epidermidis and type I (32.1%) in S. haemolyticus. All isolates were susceptible to linezolid and daptomycin, but 7.1% of S. haemolyticus and 2.3% of S. epidermidis isolates were resistant to tigecycline, and 1.2% each of S. haemolyticus and S. epidermidis were resistant and intermediately resistant to quinupristin/dalfopristin, respectively. S. epidermidis exhibited higher vancomycin MICs (40% with MIC of ≥2 μg/ml). Clonal typing of strains with vancomycin MIC of ≥2 μg/ml revealed the presence of different PFGE types of S. epidermidis and S. haemolyticus over a period of up to 4 years (2002-2004, 2005-2008, 2006-2009, 2010-2011). Despite the observation of a high prevalence of mecA, the clinical strains were fully susceptible to vancomycin and to the new drugs linezolid, daptomycin, tigecycline, and quinupristin/dalfopristin. The PFGE types with vancomycin MIC of ≥2 μg/ml exhibited a great diversity of SCCmec cassettes, demonstrating that S. epidermidis and S. haemolyticus may easily acquire these resistance-conferring genetic elements.

Comparison of magnetic field effects on the growth of Staphylococcus Aureus and Staphylococcus Epidermidis

NASA Astrophysics Data System (ADS)

Do, Kevin; Masood, Samina

The effects of magnetic fields were investigated on two species of bacteria: Staphylococcus Aureus and Staphylococcus Epidermidis. Both cultures were grown independently in agar plates and nutrient broth with exposure to various conditions of static and oscillating magnetic fields. The effects were characterized by growth rate measurements via changes in optical density (OD) over incubation periods of 24-28 hours. Significant effects on the growth rates of both species were observed in the case of the time-varying magnetic field.

Draft Genome Sequence of Vancomycin-Heteroresistant Staphylococcus epidermidis Strain UC7032, Isolated from Food

PubMed Central

Pietta, Ester; Bassi, Daniela; Fontana, Cecilia; Puglisi, Edoardo; Cappa, Fabrizio; Cocconcelli, Pier Sandro

2013-01-01

Staphylococcus epidermidis strain UC7032 was isolated from ready-to-eat cured meat and is heteroresistant to glycopeptide antibiotics. The draft whole-genome analysis revealed that this strain shows common characteristics typical of strains that are involved in nosocomial infections. PMID:24072859

Metabolic activity, urease production, antibiotic resistance and virulence in dual species biofilms of Staphylococcus epidermidis and Staphylococcus aureus.

PubMed

Vandecandelaere, Ilse; Van Nieuwerburgh, Filip; Deforce, Dieter; Coenye, Tom

2017-01-01

In this paper, the metabolic activity in single and dual species biofilms of Staphylococcus epidermidis and Staphylococcus aureus isolates was investigated. Our results demonstrated that there was less metabolic activity in dual species biofilms compared to S. aureus biofilms. However, this was not observed if S. aureus and S. epidermidis were obtained from the same sample. The largest effect on metabolic activity was observed in biofilms of S. aureus Mu50 and S. epidermidis ET-024. A transcriptomic analysis of these dual species biofilms showed that urease genes and genes encoding proteins involved in metabolism were downregulated in comparison to monospecies biofilms. These results were subsequently confirmed by phenotypic assays. As metabolic activity is related to acid production, the pH in dual species biofilms was slightly higher compared to S. aureus Mu50 biofilms. Our results showed that S. epidermidis ET-024 in dual species biofilms inhibits metabolic activity of S. aureus Mu50, leading to less acid production. As a consequence, less urease activity is required to compensate for low pH. Importantly, this effect was biofilm-specific. Also S. aureus Mu50 genes encoding virulence-associated proteins (Spa, SplF and Dps) were upregulated in dual species biofilms compared to monospecies biofilms and using Caenorhabditis elegans infection assays, we demonstrated that more nematodes survived when co-infected with S. epidermidis ET-024 and S. aureus mutants lacking functional spa, splF or dps genes, compared to nematodes infected with S. epidermidis ET-024 and wild- type S. aureus. Finally, S. epidermidis ET-024 genes encoding resistance to oxacillin, erythromycin and tobramycin were upregulated in dual species biofilms and increased resistance was subsequently confirmed. Our data indicate that both species in dual species biofilms of S. epidermidis and S. aureus influence each other's behavior, but additional studies are required necessary to elucidate the exact mechanism(s) involved.

Metabolic activity, urease production, antibiotic resistance and virulence in dual species biofilms of Staphylococcus epidermidis and Staphylococcus aureus

PubMed Central

Vandecandelaere, Ilse; Van Nieuwerburgh, Filip; Deforce, Dieter

2017-01-01

In this paper, the metabolic activity in single and dual species biofilms of Staphylococcus epidermidis and Staphylococcus aureus isolates was investigated. Our results demonstrated that there was less metabolic activity in dual species biofilms compared to S. aureus biofilms. However, this was not observed if S. aureus and S. epidermidis were obtained from the same sample. The largest effect on metabolic activity was observed in biofilms of S. aureus Mu50 and S. epidermidis ET-024. A transcriptomic analysis of these dual species biofilms showed that urease genes and genes encoding proteins involved in metabolism were downregulated in comparison to monospecies biofilms. These results were subsequently confirmed by phenotypic assays. As metabolic activity is related to acid production, the pH in dual species biofilms was slightly higher compared to S. aureus Mu50 biofilms. Our results showed that S. epidermidis ET-024 in dual species biofilms inhibits metabolic activity of S. aureus Mu50, leading to less acid production. As a consequence, less urease activity is required to compensate for low pH. Importantly, this effect was biofilm-specific. Also S. aureus Mu50 genes encoding virulence-associated proteins (Spa, SplF and Dps) were upregulated in dual species biofilms compared to monospecies biofilms and using Caenorhabditis elegans infection assays, we demonstrated that more nematodes survived when co-infected with S. epidermidis ET-024 and S. aureus mutants lacking functional spa, splF or dps genes, compared to nematodes infected with S. epidermidis ET-024 and wild- type S. aureus. Finally, S. epidermidis ET-024 genes encoding resistance to oxacillin, erythromycin and tobramycin were upregulated in dual species biofilms and increased resistance was subsequently confirmed. Our data indicate that both species in dual species biofilms of S. epidermidis and S. aureus influence each other’s behavior, but additional studies are required necessary to elucidate the exact mechanism(s) involved. PMID:28263995

Characterization of the antibacterial activity and the chemical components of the volatile oil of the leaves of Rubus parvifolius L.

PubMed

Cai, Yongqing; Hu, Xiaogang; Huang, Mingchun; Sun, Fengjun; Yang, Bo; He, Juying; Wang, Xianfeng; Xia, Peiyuan; Chen, Jianhong

2012-06-25

Rubus parvifolius L. (Rp) is a medicinal herb that possesses antibacterial activity. In this study, we extracted the volatile oil from the leaves of Rp to assess its antibacterial activity and analyze its chemical composition. A uniform distribution design was used to optimize the extraction procedure, which yielded 0.36% (w/w) of light yellowish oil from the water extract of Rp leaves. We found that the extracted oil effectively inhibited the growth of a wide range of Gram positive and negative bacteria, including Staphylococcus aureus, Staphylococcus epidermidis, Enterococcus faecalis, Escherichia coli, Pseudomonas aeruginosa, Acinetobacter baumanii, Bacillus cloacae, and Klebsiella pneumoniae. We further analyzed the components contained in the hydro-distillated Rp volatile oil by gas chromatography-mass spectroscopy. Twenty nine compounds were identified, including 4-hydroxy-3-methoxystyrene (66%), 3,7,11,15-tetramethyl-2-hexadecen-1-ol (10%) and 4-tert-butylbenzoic acid (2%). Our results suggest that one or multiple constituents contained in Rp volatile oil may account for its antibacterial activity.

Antimicrobial Analysis of an Antiseptic Made from Ethanol Crude Extracts of P. granatum and E. uniflora in Wistar Rats against Staphylococcus aureus and Staphylococcus epidermidis

PubMed Central

Bernardo, Thaís Honório Lins; Sales Santos Veríssimo, Regina Célia; Alvino, Valter; Silva Araujo, Maria Gabriella; Evangelista Pires dos Santos, Raíssa Fernanda; Maurício Viana, Max Denisson; de Assis Bastos, Maria Lysete; Alexandre-Moreira, Magna Suzana; de Araújo-Júnior, João Xavier

2015-01-01

Introduction. Surgical site infection remains a challenge for hospital infection control, especially when it relates to skin antisepsis in the surgical site. Objective. To analyze the antimicrobial activity in vivo of an antiseptic from ethanol crude extracts of P. granatum and E. uniflora against Gram-positive and Gram-negative bacteria. Methods. Agar drilling and minimal inhibitory tests were conducted for in vitro evaluation. In the in vivo bioassay were used Wistar rats and Staphylococcus aureus (ATCC 25923) and Staphylococcus epidermidis (ATCC 14990). Statistical analysis was performed through variance analysis and Scott-Knott cluster test at 5% probability and significance level. Results. In the in vitro, ethanolic extracts of Punica granatum and Eugenia uniflora and their combination showed the best antimicrobial potential against S. epidermidis and S. aureus. In the in vivo bioassay against S. epidermidis, there was no statistically significant difference between the tested product and the patterns used after five minutes of applying the product. Conclusion. The results indicate that the originated product is an antiseptic alternative source against S. epidermidis compared to chlorhexidine gluconate. It is suggested that further researches are to be conducted in different concentrations of the test product, evaluating its effectiveness and operational costs. PMID:26146655

Genotype and enterotoxigenicity of Staphylococcus epidermidis isolate from ready to eat meat products.

PubMed

Podkowik, Magdalena; Seo, Keun Seok; Schubert, Justyna; Tolo, Isaiah; Robinson, D Ashley; Bania, Jacek; Bystroń, Jarosław

2016-07-16

We have previously shown that potentially pathogenic isolates of Staphylococcus epidermidis occur at high incidence in ready-to-eat food. Now, within 164 samples of ready-to-eat meat products we identified 32 S. epidermidis isolates. In 8 isolates we detected the genes encoding for staphylococcal enterotoxins, but in 7 S. epidermidis isolates these genes were not stable over passages. One isolate designated 4S was shown to stably harbour sec and sel genes. In the genome sequence of S. epidermidis 4S we identified 21,426-bp region flanked by direct-repeats, encompassing sec and sel genes, corresponding to the previously described composite staphylococcal pathogenicity island (SePI) in S. epidermidis FRI909. Alignment of S. epidermidis 4S and S. epidermidis FRI909 SePIs revealed 6 nucleotide mismatches located in 5 of the total of 29 ORFs. Genomic location of S. epidermidis 4S SePI was the same as in FRI909. S. epidermidis 4S is a single locus variant of ST561, being genetically different from FRI909. SECepi was secreted by S. epidermidis 4S to BHI broth ranging from 14 to almost 36μg/mL, to milk ranging from 6 to 9ng/mL, to beef meat juice from 2 to 3μg/mL and to pork meat juice from 1 to 2μg/mL after 24 and 48h of cultivation, respectively. We provide the first evidence that S. epidermidis occurring in food bears an element encoding an orthologue to Staphylococcus aureus SEC, and that SECepi can be produced in microbial broth, milk and meat juices. Regarding that only enterotoxins produced by S. aureus are officially tracked in food in EU, the ability to produce enterotoxin by S. epidermidis pose real risk for food safety. Copyright © 2016 Elsevier B.V. All rights reserved.

Evaluation of the VITEK 2 System for Identification and Antimicrobial Susceptibility Testing of Medically Relevant Gram-Positive Cocci

PubMed Central

Ligozzi, Marco; Bernini, Cinzia; Bonora, Maria Grazia; de Fatima, Maria; Zuliani, Jessica; Fontana, Roberta

2002-01-01

A study was conducted to evaluate the new VITEK 2 system (bioMérieux) for identification and antibiotic susceptibility testing of gram-positive cocci. Clinical isolates of Staphylococcus aureus (n = 100), coagulase-negative staphylococci (CNS) (n = 100), Enterococcus spp. (n = 89), Streptococcus agalactiae (n = 29), and Streptococcus pneumoniae (n = 66) were examined with the ID-GPC identification card and with the AST-P515 (for staphylococci), AST-P516 (for enterococci and S. agalactiae) and AST-P506 (for pneumococci) susceptibility cards. The identification comparison methods were the API Staph for staphylococci and the API 20 Strep for streptococci and enterococci; for antimicrobial susceptibility testing, the agar dilution method according to the procedure of the National Committee for Clinical Laboratory Standards (NCCLS) was used. The VITEK 2 system correctly identified to the species level (only one choice or after simple supplementary tests) 99% of S. aureus, 96.5% of S. agalactiae, 96.9% of S. pneumoniae, 92.7% of Enterococcus faecalis, 91.3% of Staphylococcus haemolyticus, and 88% of Staphylococcus epidermidis but was least able to identify Enterococcus faecium (71.4% correct). More than 90% of gram-positive cocci were identified within 3 h. According to the NCCLS breakpoints, antimicrobial susceptibility testing with the VITEK 2 system gave 96% correct category agreement, 0.82% very major errors, 0.17% major errors, and 2.7% minor errors. Antimicrobial susceptibility testing showed category agreement from 94 to 100% for S. aureus, from 90 to 100% for CNS, from 91 to 100% for enterococci, from 96 to 100% for S. agalactiae, and from 91 to 100% for S. pneumoniae. Microorganism-antibiotic combinations that gave very major errors were CNS-erythromycin, CNS-oxacillin, enterococci-teicoplanin, and enterococci-high-concentration gentamicin. Major errors were observed for CNS-oxacillin and S. agalactiae-tetracycline combinations. In conclusion the results of this study indicate that the VITEK 2 system represents an accurate and acceptable means for performing identification and antibiotic susceptibility tests with medically relevant gram-positive cocci. PMID:11980942

21 CFR 520.90b - Ampicillin trihydrate tablets.

Code of Federal Regulations, 2011 CFR

2011-04-01

...., Staphylococcus spp., E., coli, P. mirabilis, and Enterococcus spp.; gastrointestinal infections due to Staphylococcus spp., Streptococcus spp., Enterococcus spp., and E. coli. ; infections associated with abscesses..., tonsillitis, and bronchitis due to Streptococcus spp., Staphylococcus spp., Escherichia coli, Proteus...

21 CFR 520.90b - Ampicillin trihydrate tablets.

Code of Federal Regulations, 2010 CFR

2010-04-01

...., Staphylococcus spp., E., coli, P. mirabilis, and Enterococcus spp.; gastrointestinal infections due to Staphylococcus spp., Streptococcus spp., Enterococcus spp., and E. coli. ; infections associated with abscesses..., tonsillitis, and bronchitis due to Streptococcus spp., Staphylococcus spp., Escherichia coli, Proteus...

Complete Genome Sequence of Staphylococcus epidermidis 1457

PubMed Central

Galac, Madeline R.; Stam, Jason; Maybank, Rosslyn; Hinkle, Mary; Mack, Dietrich; Rohde, Holger; Roth, Amanda L.

2017-01-01

ABSTRACT Staphylococcus epidermidis 1457 is a frequently utilized strain that is amenable to genetic manipulation and has been widely used for biofilm-related research. We report here the whole-genome sequence of this strain, which encodes 2,277 protein-coding genes and 81 RNAs within its 2.4-Mb genome and plasmid. PMID:28572323

Hospital strain colonization by Staphylococcus epidermidis.

PubMed

Blum-Menezes, D; Bratfich, O J; Padoveze, M C; Moretti, M L

2009-03-01

The skin and mucous membranes of healthy subjects are colonized by strains of Staphylococcus epidermidis showing a high diversity of genomic DNA polymorphisms. Prolonged hospitalization and the use of invasive procedures promote changes in the microbiota with subsequent colonization by hospital strains. We report here a patient with prolonged hospitalization due to chronic pancreatitis who was treated with multiple antibiotics, invasive procedures and abdominal surgery. We studied the dynamics of skin colonization by S. epidermidis leading to the development of catheter-related infections and compared the genotypic profile of clinical and microbiota strains by pulsed field gel electrophoresis. During hospitalization, the normal S. epidermidis skin microbiota exhibiting a polymorphic genomic DNA profile was replaced with a hospital-acquired biofilm-producer S. epidermidis strain that subsequently caused repetitive catheter-related infections.

Internalisation potential of Escherichia coli O157:H7, Listeria monocytogenes, Salmonella enterica subsp. enterica serovar Typhimurium and Staphylococcus aureus in lettuce seedlings and mature plants.

PubMed

Standing, Taryn-Ann; du Plessis, Erika; Duvenage, Stacey; Korsten, Lise

2013-06-01

The internalisation potential of Listeria monocytogenes, Staphylococcus aureus, Escherichia coli O157:H7 and Salmonella enterica subsp. enterica serovar Typhimurium in lettuce was evaluated using seedlings grown in vermiculite in seedling trays as well as hydroponically grown lettuce. Sterile distilled water was spiked with one of the four human pathogenic bacteria (10(5) CFU/mL) and used to irrigate the plants. The potential for pathogen internalisation was investigated over time using light microscopy, transmission electron microscopy and viable plate counts. Additionally, the identities of the pathogens isolated from internal lettuce plant tissues were confirmed using polymerase chain reaction with pathogen-specific oligonucleotides. Internalisation of each of the human pathogens was evident in both lettuce seedlings and hydroponically grown mature lettuce plants. To our knowledge, this is the first report of S. aureus internalisation in lettuce plants. In addition, the levels of background microflora in the lettuce plants were determined by plate counting and the isolates identified using matrix-assisted laser ionisation-time of flight (MALDI-TOF). Background microflora assessments confirmed the absence of the four pathogens evaluated in this study. A low titre of previously described endophytes and soil inhabitants, i.e., Enterobacter cloacae, Enterococcus faecalis, Lysinibacillus fusiformis, Rhodococcus rhodochrous, Staphylococcus epidermidis and Staphylococcus hominis were identified.

Isolation of methicillin-resistant Staphylococcus spp. from ready-to-eat fish products.

PubMed

Sergelidis, D; Abrahim, A; Papadopoulos, T; Soultos, N; Martziou, E; Koulourida, V; Govaris, A; Pexara, A; Zdragas, A; Papa, A

2014-11-01

A hundred samples from ready-to-eat (RTE) fish products were examined for the presence and antimicrobial susceptibility of Staphylococcus spp. Staphylococci were isolated from 43% of these samples (n = 100). The identified species in the samples were Staphylococcus aureus (7%), Staphylococcus epidermidis (13%), Staphylococcus xylosus (12%), Staphylococcus sciuri (4%), Staphylococcus warneri (3%), Staphylococcus saprophyticus (2%), Staphylococcus schleiferi (1%) and Staphylococcus auricularis (1%). Two Staph. aureus (MRSA) isolates, three Staph. epidermidis (MRSE), five Staph. xylosus, four Staph. sciuri, one Staph. schleiferi and one Staph. saprophyticus isolates were resistant to oxacillin and all of them carried the mecA gene. The two MRSA isolates belonged to the spa types t316 (ST359) and t548 (ST5) and none of them was able to produce enterotoxins. Pulsed field gel electrophoresis for Staph. aureus and Staph. epidermidis isolates revealed 6 and 11 distinct PFGE types, respectively, reflecting diversity. The presence of methicillin-resistant staphylococci, especially MRSA and MRSE, in RTE fish products may constitute a potential health risk for consumers. This study provides the first data on the occurrence of methicillin-resistant Staphylococcus aureus and methicillin-resistant coagulase-negative staphylococci in salted and smoked fish products in Greece. These results are important and useful for Staphylococcus spp. risk assessment and management programmes for ready-to-eat fish products. © 2014 The Society for Applied Microbiology.

Identification of Staphylococcus epidermidis with transferrable mupirocin resistance from canine skin.

PubMed

Rossi, C C; Salgado, B A B; Barros, E M; de Campos Braga, P A; Eberlin, M N; Lilenbaum, W; Giambiagi-deMarval, M

2018-05-01

Resistance to mupirocin was analysed in Staphylococcus spp. isolated from healthy dogs (n=21) and dogs with pyoderma (n=47) or otitis externa (n=52). Isolates were identified to species level by MALDI-TOF and PCR-RFLP of the groEL gene. One isolate of Staphylococcus epidermidis from the skin of a healthy dog, which harboured a plasmid carrying the mupA gene, was resistant to mupirocin. Copyright © 2018 Elsevier Ltd. All rights reserved.

Potential use of Bacillus thuringiensis bacteriocins to control antibiotic-resistant bacteria associated with mastitis in dairy goats.

PubMed

Gutiérrez-Chávez, A J; Martínez-Ortega, E A; Valencia-Posadas, M; León-Galván, M F; de la Fuente-Salcido, N M; Bideshi, D K; Barboza-Corona, J E

2016-01-01

Mastitis caused by microbial infections in dairy goats reduces milk yield, modifies milk composition, and potentially contributes to morbidity in herds and consumers of dairy products. Microorganisms associated with mastitis in dairy goats are commonly controlled with antibiotics, but it is known that continued use of these chemical agents promotes antibiotic resistance among bacterial populations. Recently, it has been shown that bacteriocins of Bacillus thuringiensis inhibit growth of food-borne pathogens and also bacteria associated with bovine mastitis. However, there is no report on their ability to inhibit microorganisms linked to mastitis in dairy goats. In this study, using 16S rDNA and ITS regions of rDNA, we identified nine bacterial isolates and an encapsulated yeast associated with mastitis in dairy goats. Enterococcus durans, Brevibacillus sp., and Staphylococcus epidermidis 2 were resistant to, respectively, 75, ~67, ~42, and ~42 % of the antibiotics screened. In addition, 60 % of the bacterial isolates were resistant to penicillin, ampicillin, vancomycin, and dicloxacillin. Importantly, 60 % of the isolates were inhibited by the bacteriocins, but S. epidermidis 1, Enterobacter sp., Escherichia vulneris, and Cryptococcus neoformans were not susceptible to these antimicrobial peptides. Using Brevibacillus sp. and Staphylococcus chromogenes as indicator bacteria, we show that peptides of ~10 kDa that correspond to the molecular mass of bacteriocins used in this study are responsible for the inhibitory activity. Our results demonstrate that multiple antibiotic-resistant bacteria associated with subclinical mastitis in dairy goats from Guanajuato, Mexico, are susceptible to bacteriocins produced by B. thuringiensis.

Composition and antimicrobial activity of Marrubium incanum Desr. (Lamiaceae) essential oil.

PubMed

Petrović, Silvana; Pavlović, Milica; Maksimović, Zoran; Milenković, Marina; Couladis, Maria; Tzakouc, Olga; Niketić, Marjan

2009-03-01

The essential oil from the aerial parts of Marrubium incanum Desr. (Lamiaceae), obtained by hydrodistillation, was analyzed by GC and GC-MS. Forty-six compounds were identified, representing 96.3% of the total oil. The main components of the oil were (E)-caryophyllene (27.0%), germacrene D (26.2%) and bicyclogermacrene (11.5%). The microbial growth inhibitory properties of the isolated essential oil were determined using the agar diffusion and broth microdilution method against seven bacterial species (Staphylococcus aureus ATCC 25923, S. epidermidis ATCC 12228, Micrococcus flavus ATCC 10240, Enterococcus faecalis ATCC 29212, Escherichia coli ATCC 25922, Klebsiella pneumoniae NCIMB 9111, and Pseudomonas aeruginosa ATCC 27853), and two strains of the yeast Candida albicans (ATCC 10259 and ATCC24433). The essential oil showed activity against all the microorganisms tested, but differences in microbial susceptibility were registered.

Staphylococcus aureus, Staphylococcus epidermidis and Staphylococcus haemolyticus: methicillin-resistant isolates are detected directly in blood cultures by multiplex PCR.

PubMed

Pereira, Eliezer M; Schuenck, Ricardo P; Malvar, Karoline L; Iorio, Natalia L P; Matos, Pricilla D M; Olendzki, André N; Oelemann, Walter M R; dos Santos, Kátia R N

2010-03-31

In this study, we standardized and evaluated a multiplex-PCR methodology using specific primers to identify Staphylococcus aureus, Staphylococcus epidermidis and Staphylococcus haemolyticus and their methicillin-resistance directly from blood cultures. Staphylococci clinical isolates (149) and control strains (16) previously identified by conventional methods were used to establish the multiplex PCR protocol. Subsequently, this methodology was evaluated using a fast and cheap DNA extraction protocol from 25 staphylococci positive blood cultures. A wash step of the pellet with 0.1% bovine serum albumin (BSA) solution was performed to reduce PCR inhibitors. Amplicons of 154bp (mecA gene), 271bp (S. haemolyticus mvaA gene) and 108 and 124bp (S. aureus and S. epidermidis species-specific fragments, respectively) were observed. Reliable results were obtained for 100% of the evaluated strains, suggesting that this new multiplex-PCR combined with an appropriate DNA-extraction method could be useful in the laboratory for fast and accurate identification of three staphylococci species and simultaneously their methicillin resistance directly in blood cultures.

A Multidrug-Resistant Staphylococcus epidermidis Clone (ST2) Is an Ongoing Cause of Hospital-Acquired Infection in a Western Australian Hospital

PubMed Central

McCullough, Cheryll A.; Coombs, Geoffrey W.; Monsen, Tor; Christiansen, Keryn J.

2012-01-01

We report the molecular epidemiology of 27 clinical multidrug-resistant Staphylococcus epidermidis (MDRSE) isolates collected between 2003 and 2007 in an Australian teaching hospital. The dominant genotype (sequence type 2 [ST2]) accounted for 85% of the isolates tested and was indistinguishable from an MDRSE genotype identified in European hospitals, which may indicate that highly adaptable health care-associated genotypes of S. epidermidis have emerged and disseminated worldwide in the health care setting. PMID:22442320

Complete Genome Sequence of Staphylococcus epidermidis 1457.

PubMed

Galac, Madeline R; Stam, Jason; Maybank, Rosslyn; Hinkle, Mary; Mack, Dietrich; Rohde, Holger; Roth, Amanda L; Fey, Paul D

2017-06-01

Staphylococcus epidermidis 1457 is a frequently utilized strain that is amenable to genetic manipulation and has been widely used for biofilm-related research. We report here the whole-genome sequence of this strain, which encodes 2,277 protein-coding genes and 81 RNAs within its 2.4-Mb genome and plasmid. Copyright © 2017 Galac et al.

Clinical characteristics of Staphylococcus epidermidis: a systematic review

PubMed Central

Namvar, Amirmorteza Ebrahimzadeh; Bastarahang, Sara; Abbasi, Niloufar; Ghehi, Ghazaleh Sheikhi; Farhadbakhtiarian, Sara; Arezi, Parastoo; Hosseini, Mahsa; Baravati, Sholeh Zaeemi; Jokar, Zahra; Chermahin, Sara Ganji

2014-01-01

Staphylococci are known as clustering Gram-positive cocci, nonmotile, non-spore forming facultatively anaerobic that classified in two main groups, coagulase-positive and coagulase-negative. Staphylococcus epidermidis with the highest percentage has the prominent role among coagulase-negative Staphylococci that is the most important reason of clinical infections. Due to various virulence factors and unique features, this microorganism is respected as a common cause of nosocomial infections. Because of potential ability in biofilm formation and colonization in different surfaces, also using of medical implant devices in immunocompromised and hospitalized patients the related infections have been increased. In recent decades the clinical importance and the emergence of methicillin-resistant Staphylococcus epidermidis strains have created many challenges in the treatment process. PMID:25285267

Staphylococcus epidermidis and Staphylococcus haemolyticus: detection of biofilm genes and biofilm formation in blood culture isolates from patients in a Brazilian teaching hospital.

PubMed

Pinheiro, Luiza; Brito, Carla Ivo; Oliveira, Adilson de; Pereira, Valéria Cataneli; Cunha, Maria de Lourdes Ribeiro de Souza da

2016-09-01

Infections with coagulase-negative staphylococci are often related to biofilm formation. This study aimed to detect biofilm formation and biofilm-associated genes in blood culture isolates of Staphylococcus epidermidis and S. haemolyticus. Half (50.6%) of the 85 S. epidermidis isolates carried the icaAD genes and 15.3% the bhp gene, while these numbers were 42.9% and 0 for S. haemolyticus, respectively. According to the plate test, 30 S. epidermidis isolates were biofilm producers and 40% of them were strongly adherent, while only one (6%) of the 17 S. haemolyticus biofilm-producing isolates exhibited a strongly adherent biofilm. The concomitant presence of icaA and icaD was significantly associated with the plate and tube test results (P ≤ 0.0004). The higher frequency of icaA in S. epidermidis and of icaD in S. haemolyticus is correlated with the higher biofilm-producing capacity of the former since, in contrast to IcaD, IcaA activity is sufficient to produce small amounts of polysaccharide. Although this study emphasizes the importance of icaAD and bhp for biofilm formation in S. epidermidis, other mechanisms seem to be involved in S. haemolyticus. Copyright © 2016 Elsevier Inc. All rights reserved.

Diversity of staphylococcal cassette chromosome mec structures in methicillin-resistant Staphylococcus epidermidis and Staphylococcus haemolyticus strains among outpatients from four countries.

PubMed

Ruppé, Etienne; Barbier, François; Mesli, Yasmine; Maiga, Aminata; Cojocaru, Radu; Benkhalfat, Mokhtar; Benchouk, Samia; Hassaine, Hafida; Maiga, Ibrahim; Diallo, Amadou; Koumaré, Abdel Karim; Ouattara, Kalilou; Soumaré, Sambou; Dufourcq, Jean-Baptiste; Nareth, Chhor; Sarthou, Jean-Louis; Andremont, Antoine; Ruimy, Raymond

2009-02-01

In staphylococci, methicillin (meticillin) resistance (MR) is mediated by the acquisition of the mecA gene, which is carried on the size and composition variable staphylococcal cassette chromosome mec (SCCmec). MR has been extensively studied in Staphylococcus aureus, but little is known about MR coagulase-negative staphylococci (MR-CoNS). Here, we describe the diversity of SCCmec structures in MR-CoNS from outpatients living in countries with contrasting environments: Algeria, Mali, Moldova, and Cambodia. Their MR-CoNS nasal carriage rates were 29, 17, 11, and 31%, respectively. Ninety-six MR-CoNS strains, comprising 75 (78%) Staphylococcus epidermidis strains, 19 (20%) Staphylococcus haemolyticus strains, 1 (1%) Staphylococcus hominis strain, and 1 (1%) Staphylococcus cohnii strain, were analyzed. Eighteen different SCCmec types were observed, with 28 identified as type IV (29%), 25 as type V (26%), and 1 as type III (1%). Fifteen strains (44%) were untypeable for their SCCmec. Thirty-four percent of MR-CoNS strains contained multiple ccr copies. Type IV and V SCCmec were preferentially associated with S. epidermidis and S. haemolyticus, respectively. MR-CoNS constitute a widespread and highly diversified MR reservoir in the community.

Genotypic Diversity of Methicillin-Resistant Coagulase-Negative Staphylococci Isolated from Inpatients and Outpatients.

PubMed

Talebi, Malihe; Shafiee, Mohammad; Sadeghi, Javad; Moghadam, Nasrin Asghari; Saifi, Mahnaz; Pourshafie, Mohammad R

2016-03-01

We investigated the prevalence of methicillin-resistant coagulase-negative staphylococci (MRCoNS) isolated from hospitalized patients and outpatients (OP). Out of 350 staphylococcal isolates collected from three hospitals, 190 were coagulase-negative staphylococci (CoNS). These isolates were subjected to antimicrobial susceptibility tests, detection of mecA, and pulsed-field gel electrophoresis (PFGE) typing. Among the 190 isolated CoNS, Staphylococcus epidermidis (47.3%) and Staphylococcus haemolyticus (44.2%) were the most prevalent species. Other CoNS species that were isolated were Staphylococcus saprophyticus (2.1%), Staphylococcus warneri (2.1%), Staphylococcus simulans (1.6%), Staphylococcus capitis (1.1%), Staphylococcus schleiferi (1.1%), and Staphylococcus hominis (0.5%). The rate of resistance to methicillin was 60% with 58 (50%) S. epidermidis and 55 (49%) S. haemolyticus. The rate of resistance to 13 antibiotics tested with the lowest and highest to chloramphenicol and penicillin, respectively. High clonal diversity with different PFGE patterns was obtained for methicillin-resistant S. epidermidis and S. haemolyticus by 32 and 31 types, respectively. Our results indicated that the dissemination of MRCoNS is widespread in Tehran. The majority of these isolates showed distinct genotyping patterns. At the same time, the common patterns were found among the MRCoNS obtained from outpatient and inpatient isolates, suggestive of an epidemiological link.

Establishment and analysis of in vitro biomass from Salvia corrugata Vahl. and evaluation of antimicrobial activity.

PubMed

Bisio, Angela; Fraternale, Daniele; Schito, Anna Maria; Parricchi, Anita; Dal Piaz, Fabrizio; Ricci, Donata; Giacomini, Mauro; Ruffoni, Barbara; De Tommasi, Nunziatina

2016-02-01

Demethylfruticuline A and fruticuline A, the most abundant compounds from the surface extract of Salvia corrugata Vahl., have shown antibacterial, antitumor and cytotoxic activities. In order to obtain these icetexane diterpenes from in vitro cultures of S. corrugata, protocols were developed for callus production, micropropagation and shoot regeneration. Analysis of the regenerated shoots showed the presence of both icetexanes, micropropagated plants contained only fruticuline A, while the callus contained trace amounts of both diterpenes. The yield of fruticuline A was higher in the methanolic extract of regenerated shoots than in those of fresh leaves and fresh shoot tips. In addition to these diterpenes, the regenerated shoot and micropropagated plant extracts afforded seven other diterpenes, one icetexane and six abietanes, identified by UV, IR, 1D- and 2D-NMR and HR-MS analysis. Five compounds (19-acetoxy-7α-hydroxyroyleanone, 7β,20-epoxy-11,12,19-trihydroxyabieta-8,11,13-triene, 7,20-dihydrofruticuline A, 7β-acetoxy-20-hydroxy-19,20-epoxyroyleanone, 7β-ethoxy-6β,20:19,20-diepoxyroyleanone) were previously undescribed. Although the crude plant surface extract did not possess any antibacterial activity, methanolic extracts of in vitro tissues and two compounds, namely 7β-acetoxy-20-hydroxy-19,20-epoxyroyleanone and 7β-ethoxy-6β,20:19,20-diepoxyroyleanone, isolated in suitable amounts, were active in varying degrees against multidrug resistant clinical strains of Staphylococcus aureus, Staphylococcus epidermidis, Enterococcus faecalis and Enterococcus faecium, displaying MIC values ranging from 32, 64 to 128μg/mL. Copyright © 2015 Elsevier Ltd. All rights reserved.

Effect of Ottoman Viper (Montivipera xanthina (Gray, 1849)) Venom on Various Cancer Cells and on Microorganisms.

PubMed

Yalcın, Husniye Tansel; Ozen, Mehmet Ozgün; Gocmen, Bayram; Nalbantsoy, Ayse

2014-01-01

Cytotoxic and antimicrobial effects of Montivipera xanthina venom against LNCaP, MCF-7, HT-29, Saos-2, Hep3B, Vero cells and antimicrobial activity against selected bacterial and fungal species: Staphylococcus aureus ATCC 25923, Escherichia coli ATCC 25922, E. coli O157H7, Enterococcus faecalis 29212, Enterococcus faecium DSM 13590, Staphylococcus epidermidis ATCC 12228, S. typhimirium CCM 5445, Proteus vulgaris ATCC 6957 and Candida albicans ATCC 10239 were studied for evaluating the potential medical benefit of this snake venom. Cytotoxicity of venom was determined using MTT assay. Snake venom cytotoxicity was expressed as the venom dose that killed 50 % of the cells (IC50). The antimicrobial activity of venom was studied by minimal inhibitory concentration (MIC) and disc diffusion assay. MIC was determined using broth dilution method. The estimated IC50 values of venom varied from 3.8 to 12.7 or from 1.9 to 7.2 μg/ml after treatment with crude venom for 24 or 48 h for LNCaP, MCF-7, HT-29 and Saos-2 cells. There was no observable cytotoxic effect on Hep3B and Vero cells. Venom exhibited the most potent activity against C. albicans (MIC, 7.8 μg/ml and minimal fungicidal concentration, 62.5 μg/ml) and S. aureus (MIC, 31.25 μg/ml). This study is the first report showing the potential of M. xanthina venom as an alternative therapeutic approach due to its cytotoxic and antimicrobial effects.

Staphylococcus epidermidis biofilm formation and structural organization on different types of intraocular lenses under in vitro flow conditions.

PubMed

Baillif, Stéphanie; Leduff, Frank; Hartmann, Daniel J; Kodjikian, Laurent

2013-01-01

To compare the adherence and structural organization of Staphylococcus epidermidis biofilm on intraocular lenses (IOLs). IOLs made of 3 different biomaterials [polymethyl methacrylate (PMMA), hydrophilic acrylic or hydrophobic acrylic] were incubated into an S. epidermidis bacterial solution. Scanning electron microscopy was used to count the bound bacteria and to analyze the structural biofilm architecture. After 4-6 h of incubation, adherence was statistically weakest on the hydrophilic acrylic polymer. On the hydrophobic acrylic material, the bacterial cells tended to cover the substratum in a horizontal spread in a continuous monolayer. On the hydrophilic acrylic material or on the PMMA material bacterial cells tended to form only few, small scattered cell clusters. The data suggest that the pattern of S. epidermidis adhesion varies with the IOL biomaterial. Hydrophobic IOLs seem to be more permissive to S. epidermidis adhesion. Copyright © 2013 S. Karger AG, Basel.

[FUNCTION OF INTERCELLULAR ADHESION A, FIBRINOGEN BINDING PROTEIN, AND ACCUMULATION-ASSOCIATED PROTEIN GENES IN FORMATION OF STAPHYLOCOCCUS EPIDERMIDIS-CANDIDA ALBICANS MIXED SPECIES BIOFILMS].

PubMed

Wang, Xiaoyan; Chen, Ying; Huang, Yunchao; Zhou, Youquan; Zhao, Guangqiang; Ye, Lianhua; Lei, Yujie; Tang, Qi

2015-01-01

To explore the function of intercellular adhesion A (icaA), fibrinogen binding protein (fbe), and accumulation-associated protein (aap) genes in formation of Staphylococcus epidermidis-Candida albicans mixed species biofilms. The experiment was divided into 3 groups: single culture of Staphylococcus epidermidis ATCC35984 (S. epidermidis group) or Candida albicans ATCC10231 (C. albicans group), and co-culture of two strains (mixed group) to build in vitro biofilm model. Biofilm mass was detected by crystal violet semi-quantitative adherence assay at 2, 4, 6, 8, 12, 24, 48, and 72 hours after incubation. XTT assay was performed to determine the growth kinetics in the same time. Scanning electron microscopy (SEM) was used to observe the ultrastructure of the biofilms after 24 and 72 hours of incubation. The expressions of icaA, fbe, and aap genes were analyzed by real-time fluorescent quantitative PCR. Crystal violet semi-quantitative adherence assay showed that the biofilms thickened at 12 hours in the S. epidermidis and mixed groups; after co-cultured for 72 hours the thickness of biofilm in mixed group was more than that in the S. epidermidis group, and there was significant difference between 2 groups at the other time (P < 0.05) except at 72 hours (P > 0.05). In C. albicans group, the biofilm started to grow at 12 hours of cultivation, but the thickness of the biofilm was significantly lower than that in the mixed group in all the time points (P < 0.05). XTT assay showed that the overall growth speed in the mixed group was greater than that in the C. albicans group, and it was greater than that in the S. epidermidis group at 48 hours; there was no significant difference in the growth speed between the mixed groups and the S. epidermidis group in the other time points (P > 0.05) except at 12 hours (P < 0.05). The absorbance (A) value in the mixed group was lower than that in the S. epidermidis group at 2 and 4 hours, but no significant difference was shown (P > 0.05); the A value of mixed group was significantly higher than that of the C. albicans group after 6 hours (P < 0.05). SEM observation showed that mature biofilms with complex structure formed in all groups. The real-time fluorescent quantitative PCR showed the expressions of fbe, icaA, and aap genes in mixed group increased 1.93, 1.52, and 1.46 times respectively at 72 hours compared with the S. epidermidis group (P < 0.05). Mixed species biofilms have more complex structure and are thicker than single species biofilms of Staphylococcus epidermidis or Candida albicans, which is related to increased expressions of the icaA, fbe, and aap genes of Staphylococcus epidermidis.

In vitro study of antibacterial activity of the alga Sargassum oligocystum from the Persian Gulf.

PubMed

Tajbakhsh, S; Pouyan, M; Zandi, K; Bahramian, P; Sartavi, K; Fouladvand, M; Asayesh, G; Barazesh, A

2011-03-01

With due attention to the development of drug-resistant bacteria, discovering of new antibacterial compounds is needed. Algae produce numerous bioactive substances which may have pharmacological properties such as antibacterial activity. The objective of this investigation was to in vitro study of antibacterial activity of brown alga Sargassum oligocystum collected along the Bushehr coast of Persian Gulf (south west of Iran). Hot water extract, cold water extract, and hot glycerin extract were prepared. The effect of the extracts were investigated on Staphylococcus aureus (ATCC 25923), Staphylococcus epidermidis (ATCC 14990), Pseudomonas aeruginosa (ATCC 27853), and Escherichia coli (ATCC 25922). Hot water extract exhibited antibacterial activity against Staphylococcus aureus, Staphylococcus epidermidis, and Pseudomonas aeruginosa. Cold water extract and hot glycerin extract did not show antibacterial activity on any of the four test bacteria. The minimum inhibitory concentration (MIC) of hot water extract for both Staphylococcus aureus and Staphylococcus epidermidis was 3.175 mg/ml. However, the MIC of this extract for Pseudomonas aeruginosa was 9.556 mg/ml. In this study gram-positive bacteria were more susceptible to hot water extract than gram-negative bacteria. Extract of Sargassum oligocystum could be a candidate for purification and further in vivo studies.

Subacute Staphylococcus epidermidis Bacterial Endocarditis Complicated by Mitral-Aortic Intervalvular Fibrosa Pseudoaneurysm

DTIC Science & Technology

2012-12-01

Staphylococcus epidermidis Bacterial Endocarditis Complicated byMitral-Aortic Intervalvular Fibrosa Pseudoaneurysm Diane Elegino-Steffens,1 Amy Stratton,1... endocarditis . 1. Introduction The mitral-aortic intervalvular fibrosa (MAIF), also known as the mitral-aortic membrane, is a fibrous region of the heart...of his aortic valve for severe aortic regurgitation that was subsequently found to have infective endocarditis prompting antibiotic treatment. His

Chemical constituents and antimicrobial activity of the essential oil of Lantana xenica.

PubMed

Juliani, Hector R; Biurrun, Fernando; Koroch, Adolfina R; Oliva, M M; Demo, Mirta S; Trippi, Victorio S; Zygadlo, Julio A

2002-08-01

The aim of this work was to evaluate the chemical composition of Lantana xenica essential oil and its antimicrobial activity. The oil from the aerial parts of Lantana xenica Mold. (Verbenacea) was obtained by steam distillation and analyzed by gas chromatography/mass spectrometry. The major constituent of the oil was (E)-caryophyllene (35.2 %), with minor amounts of gamma-cadinene (13.3 %), alpha-pinene (9.3 %), ocimene (9.2 %) and germacrene D (6.6 %). The antimicrobial assays showed that the essential oil of L. xenica inhibited the growth of Bacillus cereus and Proteus mirabilis and both bacteria were inhibited by (E)-caryophyllene, the major component of the oil. Enterococcus faecalis, Staphylococcus epidermidis and S. aureus showed a lower inhibition. The bacteria Micrococcus luteus, Klebsiella sp., Escherichia coli and the yeast Candida albicans were insensitive to both the oil and (E)-caryophyllene.

Antimicrobial activity of the ornamental species Salvia corrugata, a potential new crop for extractive purposes.

PubMed

Bisio, Angela; Romussi, Giovanni; Russo, Eleonora; Cafaggi, Sergio; Schito, Anna Maria; Repetto, Barbara; De Tommasi, Nunziatina

2008-11-26

As a part of our search for biologically active compounds from cultivated Salvia spp. we investigated Salvia corrugata Vahl. The activity of two isolated icetaxane diterpene quinones, fruticuline A and demethylfruticuline A, was assessed against 46 bacterial pathogens, mostly resistant to several primary antibiotics. The MIC for all the inhibited Gram-positive pathogens tested showed a very narrow distribution and ranged from 32 to 64 mg/L, regardless of their resistance patterns to other antibiotics. Demethylfruticuline A was shown to be highly bactericidal (>3 log(10) CFU decrease within 24 h) against Staphylococcus aureus and S. epidermidis and bacteriostatic against Enterococcus faecalis and E. faecium. Fruticuline A manifested bacteriostatic activity against all tested strains. S. corrugata can be viewed as an interesting source for these diterpenes, which, if well tolerated in vivo, may represent new medical agents useful for the treatment of serious infections caused by resistant Gram-positive pathogens.

Technical note: Antimicrobial susceptibility of Portuguese isolates of Staphylococcus aureus and Staphylococcus epidermidis in subclinical bovine mastitis.

PubMed

Nunes, S F; Bexiga, R; Cavaco, L M; Vilela, C L

2007-07-01

To evaluate the antimicrobial resistance traits of staphylococci responsible for subclinical bovine mastitis in Portugal, the minimum inhibitory concentrations (MIC) of 7 antimicrobial agents, frequently administered for mastitis treatment, were determined for 30 Staphylococcus aureus and 31 Staphylococcus epidermidis field isolates. Beta-lactamase production was detected through the use of nitrocefin-impregnated discs. The MIC that inhibited 90% of the isolates tested (MIC90) of penicillin, oxacillin, cefazolin, gentamicin, sulfamethoxazole/trimethoprim, oxytetracycline, and enrofloxacin were, respectively, 4, 0.5, 1, 1, 0.25, 0.25, and 0.06 microg/mL for Staph. aureus and > or = 64, 8, 1, 32, > or = 64, > or = 64, and 0.06 microg/mL for Staph. epidermidis. All Staph. aureus isolates showed susceptibility to oxacillin, cefazolin, gentamicin, sulphamethoxazole/trimethoprim, and enrofloxacin. Beta-lactamase production was detected in 20 of these isolates (66.7%), all of which were resistant to penicillin. Of the 31 Staph. epidermidis tested, 24 (77.4%) were beta-lactamase positive. All isolates were susceptible to both cefazolin and enrofloxacin. Nine Staph. epidermidis isolates were resistant to oxacillin, with MIC values ranging from 4 to 8 microg/mL. The MIC values of 5 antimicrobial agents tested were higher than those reported in other countries. Enrofloxacin was the only exception, showing lower MIC values compared with other reports. Overall, the antimicrobial agents tested in our study, with the exception of penicillin, were active against the 61 isolates studied.

Comparative Genomics and Identification of an Enterotoxin-Bearing Pathogenicity Island, SEPI-1/SECI-1, in Staphylococcus epidermidis Pathogenic Strains.

PubMed

Argemi, Xavier; Nanoukon, Chimène; Affolabi, Dissou; Keller, Daniel; Hansmann, Yves; Riegel, Philippe; Baba-Moussa, Lamine; Prévost, Gilles

2018-02-25

Staphylococcus epidermidis is a leading cause of nosocomial infections, majorly resistant to beta-lactam antibiotics, and may transfer several mobile genetic elements among the members of its own species, as well as to Staphylococcus aureus ; however, a genetic exchange from S. aureus to S. epidermidis remains controversial. We recently identified two pathogenic clinical strains of S. epidermidis that produce a staphylococcal enterotoxin C3-like (SEC) similar to that by S. aureus pathogenicity islands. This study aimed to determine the genetic environment of the SEC-coding sequence and to identify the mobile genetic elements. Whole-genome sequencing and annotation of the S. epidermidis strains were performed using Illumina technology and a bioinformatics pipeline for assembly, which provided evidence that the SEC-coding sequences were located in a composite pathogenicity island that was previously described in the S. epidermidis strain FRI909, called SePI-1/SeCI-1, with 83.8-89.7% nucleotide similarity. Various other plasmids were identified, particularly p_3_95 and p_4_95, which carry antibiotic resistance genes ( hsrA and dfrG , respectively), and share homologies with SAP085A and pUSA04-2-SUR11, two plasmids described in S. aureus . Eventually, one complete prophage was identified, ΦSE90, sharing 30 out of 52 coding sequences with the Acinetobacter phage vB_AbaM_IME200. Thus, the SePI-1/SeCI-1 pathogenicity island was identified in two pathogenic strains of S. epidermidis that produced a SEC enterotoxin causing septic shock. These findings suggest the existence of in vivo genetic exchange from S. aureus to S. epidermidis .

Comparative Genomics and Identification of an Enterotoxin-Bearing Pathogenicity Island, SEPI-1/SECI-1, in Staphylococcus epidermidis Pathogenic Strains

PubMed Central

Nanoukon, Chimène; Affolabi, Dissou; Keller, Daniel; Hansmann, Yves; Riegel, Philippe; Baba-Moussa, Lamine; Prévost, Gilles

2018-01-01

Staphylococcus epidermidis is a leading cause of nosocomial infections, majorly resistant to beta-lactam antibiotics, and may transfer several mobile genetic elements among the members of its own species, as well as to Staphylococcus aureus; however, a genetic exchange from S. aureus to S. epidermidis remains controversial. We recently identified two pathogenic clinical strains of S. epidermidis that produce a staphylococcal enterotoxin C3-like (SEC) similar to that by S. aureus pathogenicity islands. This study aimed to determine the genetic environment of the SEC-coding sequence and to identify the mobile genetic elements. Whole-genome sequencing and annotation of the S. epidermidis strains were performed using Illumina technology and a bioinformatics pipeline for assembly, which provided evidence that the SEC-coding sequences were located in a composite pathogenicity island that was previously described in the S. epidermidis strain FRI909, called SePI-1/SeCI-1, with 83.8–89.7% nucleotide similarity. Various other plasmids were identified, particularly p_3_95 and p_4_95, which carry antibiotic resistance genes (hsrA and dfrG, respectively), and share homologies with SAP085A and pUSA04-2-SUR11, two plasmids described in S. aureus. Eventually, one complete prophage was identified, ΦSE90, sharing 30 out of 52 coding sequences with the Acinetobacter phage vB_AbaM_IME200. Thus, the SePI-1/SeCI-1 pathogenicity island was identified in two pathogenic strains of S. epidermidis that produced a SEC enterotoxin causing septic shock. These findings suggest the existence of in vivo genetic exchange from S. aureus to S. epidermidis. PMID:29495323

A comparison of the bacteria found on the hands of ‘homemakers’ and neonatal intensive care unit nurses

PubMed Central

Aiello, A.E.; Cimiotti, J.; Della-Latta, P.; Larson, E.L.

2007-01-01

Summary This prevalence study was conducted to compare the counts, types and antimicrobial resistance profiles of bacterial flora on the hands of individuals in the community to that of nurses at a nearby university teaching hospital, with an intense hand hygiene regimen. Hand cultures were obtained from 204 individuals during a home visit and 119 nurses in two neonatal intensive care units (NICUs). The mean total log counts of organisms were 5.73 and 5.24 for the homemakers [defined as the person (usually the mother) who is the primary person responsible for arranging childcare, cooking, cleaning etc] and nurse hands, respectively (P < 0.0001). Significantly more homemakers had Acinetobacter lwoffii, Enterobacter cloacae, Klebsiella pneumoniae, Pseudomonas aeruginosa, P. fluorescens/putida, and Staphylococcus aureus on their hands compared with the nurses (all P < 0.05). However, significantly more nurses had Enterococcus faecalis, S. epidermidis, and S. warneri on their hands (P < 0.05). Of note, the hands of nurses harboured significantly more S. epidermidis strains resistant to amoxicillin/clavulanate, cefazolin, clindamycin, erythromycin, and oxacillin and S. warneri resistant to amoxicillin/clavulanate, cefazolin, clindamycin, and oxacillin (P < 0.05). Surprisingly, significantly more trimethoprim/sulfamethoxazole-resistant S. epidermidis and ciprofloxacin-resistant S. warneri was recovered from the hands of homemakers (P < 0.05). This study demonstrates differences in prevalence, bacterial composition and antimicrobial resistance of hand flora of hospital personnel compared with homemakers. Moreover, the hands of homemakers may serve as community reservoirs for antimicrobial resistant strains of clinical importance. PMID:12919763

[Preoperatively administered flomoxef sodium concentration in aqueous humor].

PubMed

Miyamoto, Mariko; Watanabe, Yoichiro; Mizuki, Nobuhisa

2007-04-01

We intravenously administered flomoxef sodium (FMOX) 0.5-3.5 hours before cataract surgery and measured the concentration of the agent in the aqueous humor to investigate its penetration into the aqueous humor and its efficacy in the prevention of postoperative endophthalmitis. 56 patients who underwent cataract surgery were enrolled in this study. They received 1 g FMOX via a 20-minute intravenous drip beginning 0.5-3.5 hours before the operation. Aqueous humor was aspirated from the anterior chamber and assayed for FMOX concentration using high-performance liquid chromatography. The mean intraoperative FMOX concentrations in the patients' aqueous humor were 0.79 +/- 0.24 microg/ml (administered 3.5 hours before surgery)--1.47 0.79 microg/ml (administered 1.5 hours before surgery). These concentrations administered 0.5-3.0 hours before surgery sufficiently exceeded the minimum inhibitory concentration (MIC) 90 values against Staphylococcus epidermidis, Staphylococcus aureus and Propionibacterium acnes, but did not achieve the MIC90 values against Enterococcus faecalis and Pseudomonas aeruginosa. The FMOX concentrations in the aqueous humor sampling were adequate to kill bacteria in vitro. This drug may be efficacious in the prevention of postoperative endophthalmitis in patients undergoing cataract surgery.

Polyclonality of Staphylococcus epidermidis residing on the healthy ocular surface.

PubMed

Ueta, Mayumi; Iida, Tetsuya; Sakamoto, Masako; Sotozono, Chie; Takahashi, Junko; Kojima, Kentaro; Okada, Kazuhisa; Chen, Xiuhao; Kinoshita, Shigeru; Honda, Takeshi

2007-01-01

Staphylococcus epidermidis is part of the normal bacterial flora on the ocular surface. The chromosomal DNA of bacterial isolates obtained from the conjunctival sac, upper and lower lid margins, and upper and lower Meibomian glands of healthy volunteers was subjected to SmaI digestion and PFGE to study the genetic diversity of the organisms. Multiple colonies were also examined of S. epidermidis derived from the conjunctival sac of the same subjects. Lastly, commensal bacteria were harvested from the ocular surfaces of four healthy subjects once a month for 6 months, and the genetic background of the S. epidermidis isolates was analysed. It was found that bacterial strains not only from different subjects but also from multiple ocular surface sites of the same subject exhibited different PFGE patterns. In five of 42 subjects multiple colonies of S. epidermidis were isolated from the conjunctival sac; three harboured multiple colonies with different PFGE patterns, and two manifested multiple colonies with identical PFGE patterns. S. epidermidis isolated from the conjunctival sac of the same subjects over a 6-month period exhibited varying PFGE patterns. The data demonstrate the polyclonality of S. epidermidis on the healthy ocular surface.

Structural basis of Staphylococcus epidermidis biofilm formation: mechanisms and molecular interactions

PubMed Central

Büttner, Henning; Mack, Dietrich; Rohde, Holger

2015-01-01

Staphylococcus epidermidis is a usually harmless commensal bacterium highly abundant on the human skin. Under defined predisposing conditions, most importantly implantation of a medical device, S. epidermidis, however, can switch from a colonizing to an invasive life style. The emergence of S. epidermidis as an opportunistic pathogen is closely linked to the biofilm forming capability of the species. During the past decades, tremendous advance regarding our understanding of molecular mechanisms contributing to surface colonization has been made, and detailed information is available for several factors active during the primary attachment, accumulative or dispersal phase of biofilm formation. A picture evolved in which distinct factors, though appearing to be redundantly organized, take over specific and exclusive functions during biofilm development. In this review, these mechanisms are described in molecular detail, with a highlight on recent insights into multi-functional S. epidermidis cell surface proteins contributing to surface adherence and intercellular adhesion. The integration of distinct biofilm-promoting factors into regulatory networks is summarized, with an emphasis on mechanism that could allow S. epidermidis to flexibly adapt to changing environmental conditions present during colonizing or invasive life-styles. PMID:25741476

[Abscess of the spleen].

PubMed

Grubor, Nikica; Colović, Radoje; Colović, Natasa; Radak, Vladimir

2005-01-01

Splenic abscess is a rare disease but with increasing frequency. The authors present 9 patients with splenic abscess treated at the Institute of Digestive System Diseases, Clinical Centre of Serbia, in a period from January 1, 1986 to May 15, 2004. Splenic abscess was the complication of septic endocarditis in 4, trauma in 2, dental infection in 1, while in 2 cases it was the complication of chemotherapy in myeloproliferative disorders. All 9 patients had fever, 7 - abdominal pain, 4 - left shoulder pain, and 1 patient had nausea and vomiting. Higher white blood count was found in 6 patients, pleural effusion in 4, elevated left hemidiaphragm in 1 and basal pneumonia in 1 patient as well. Ultrasonography and CT were the most reliable diagnostic procedures. CT was superior in diagnosis of multiple small abscesses. Culture of the pus recovered the Enterococcus in 3 cases, Streptococcus a hemolyticus in 1, Staphylococcus epidermidis and Candida albicans in 1, Staphylococcus aureus, E. Coil and Candida albicans in 1, Staphylococcus aureus i Salmonella enteritidis in 1 case. Eight patients underwent splenectomy and 1 was cured by combined antibiotics in high doses. One patient died postoperatively due to septic endocarditis that had been present before surgery. The authors believe that splenectomy and antibiotics administered according to drug susceptibility test as well as management of underlying disease are the method of choice for splenic abscess treatment. Conservative antibiotic treatment is indicated in selected cases only.

In vitro activity of ceftaroline against staphylococci from prosthetic joint infection.

PubMed

Park, Kyung-Hwa; Greenwood-Quaintance, Kerryl E; Patel, Robin

2016-02-01

We tested the in vitro activity of ceftaroline by Etest against staphylococci recovered from patients with prosthetic joint infection, including 97 Staphylococcus aureus isolates (36%, oxacillin resistant) and 74 Staphylococcus epidermidis isolates (74%, oxacillin resistant). Ceftaroline inhibited all staphylococci at ≤0.5 μg/mL. The ceftaroline MIC(90/50) values for methicillin-susceptible S. aureus, methicillin-susceptible S. epidermidis, methicillin-resistant S. aureus, and methicillin-resistant S. epidermidis were 0.19/0.125, 0.094/0.047, 0.5/0.38, and 0.38/0.19 μg/mL, respectively. Based on these in vitro findings, ceftaroline should be further evaluated as a potential therapeutic option for the treatment of prosthetic joint infection caused by methicillin-susceptible and methicillin-resistant S. aureus and S. epidermidis. Copyright © 2016 Elsevier Inc. All rights reserved.

Biofilm extracellular DNA enhances mixed species biofilms of Staphylococcus epidermidis and Candida albicans

PubMed Central

2013-01-01

Background Polymicrobial infections are responsible for significant mortality and morbidity in adults and children. Staphylococcus epidermidis and Candida albicans are the most frequent combination of organisms isolated from polymicrobial infections. Vascular indwelling catheters are sites for mixed species biofilm formation and pose a significant risk for polymicrobial infections. We hypothesized that enhancement of biofilms in a mixed species environment increases patient mortality and morbidity. Results Mixed species biofilms of S. epidermidis and C. albicans were evaluated in vitro and in a subcutaneous catheter infection model in vivo. Mixed species biofilms were enhanced compared to single species biofilms of either S. epidermidis or C. albicans. A mixed species environment increased catheter infection and increased dissemination of S. epidermidis in mice. Microarrays were used to explore differential gene expression of S. epidermidis in the mixed species biofilms. In mixed species biofilms, compared to single species S. epidermidis biofilms, 2.7% of S. epidermidis genes were upregulated and 6% were down regulated. Staphylococcal autolysis repressors lrgA and lrgB were down regulated 36-fold and 27-fold respectively. The role of biofilm extracellular DNA was investigated by quantitation and by evaluating the effects of DNAse in a concentration and time dependent manner. S. epidermidis specific eDNA was increased in mixed species biofilms and further confirmed by degradation with DNAse. Conclusions Mixed-species biofilms are enhanced and associated with increased S. epidermidis-specific eDNA in vitro and greater systemic dissemination of S. epidermidis in vivo. Down regulation of the lrg operon, a repressor of autolysis, associated with increased eDNA suggests a possible role for bacterial autolysis in mixed species biofilms. Enhancement and systemic dissemination of S. epidermidis may explain adverse outcomes after clinical polymicrobial infections of S. epidermidis and C. albicans. PMID:24228850

Biofilm extracellular DNA enhances mixed species biofilms of Staphylococcus epidermidis and Candida albicans.

PubMed

Pammi, Mohan; Liang, Rong; Hicks, John; Mistretta, Toni-Ann; Versalovic, James

2013-11-14

Polymicrobial infections are responsible for significant mortality and morbidity in adults and children. Staphylococcus epidermidis and Candida albicans are the most frequent combination of organisms isolated from polymicrobial infections. Vascular indwelling catheters are sites for mixed species biofilm formation and pose a significant risk for polymicrobial infections. We hypothesized that enhancement of biofilms in a mixed species environment increases patient mortality and morbidity. Mixed species biofilms of S. epidermidis and C. albicans were evaluated in vitro and in a subcutaneous catheter infection model in vivo. Mixed species biofilms were enhanced compared to single species biofilms of either S. epidermidis or C. albicans. A mixed species environment increased catheter infection and increased dissemination of S. epidermidis in mice. Microarrays were used to explore differential gene expression of S. epidermidis in the mixed species biofilms. In mixed species biofilms, compared to single species S. epidermidis biofilms, 2.7% of S. epidermidis genes were upregulated and 6% were down regulated. Staphylococcal autolysis repressors lrgA and lrgB were down regulated 36-fold and 27-fold respectively. The role of biofilm extracellular DNA was investigated by quantitation and by evaluating the effects of DNAse in a concentration and time dependent manner. S. epidermidis specific eDNA was increased in mixed species biofilms and further confirmed by degradation with DNAse. Mixed-species biofilms are enhanced and associated with increased S. epidermidis-specific eDNA in vitro and greater systemic dissemination of S. epidermidis in vivo. Down regulation of the lrg operon, a repressor of autolysis, associated with increased eDNA suggests a possible role for bacterial autolysis in mixed species biofilms. Enhancement and systemic dissemination of S. epidermidis may explain adverse outcomes after clinical polymicrobial infections of S. epidermidis and C. albicans.

Anti-biofilm properties of the antimicrobial peptide temporin 1Tb and its ability, in combination with EDTA, to eradicate Staphylococcus epidermidis biofilms on silicone catheters.

PubMed

Maisetta, Giuseppantonio; Grassi, Lucia; Di Luca, Mariagrazia; Bombardelli, Silvia; Medici, Chiara; Brancatisano, Franca Lisa; Esin, Semih; Batoni, Giovanna

2016-08-01

In search of new antimicrobials with anti-biofilm potential, in the present study activity of the frog-skin derived antimicrobial peptide temporin 1Tb (TB) against Staphylococcus epidermidis biofilms was investigated. A striking ability of TB to kill both forming and mature S. epidermidis biofilms was observed, especially when the peptide was combined with cysteine or EDTA, respectively. Kinetics studies demonstrated that the combination TB/EDTA was active against mature biofilms already after 2-4-h exposure. A double 4-h exposure of biofilms to TB/EDTA further increased the therapeutic potential of the same combination. Of note, TB/EDTA was able to eradicate S. epidermidis biofilms formed in vitro on silicone catheters. At eradicating concentrations, TB/EDTA did not cause hemolysis of human erythrocytes. The results shed light on the anti-biofilm properties of TB and suggest a possible application of the peptide in the lock therapy of catheters infected with S. epidermidis.

Influence of Surface Properties on the Adhesion of Staphylococcus epidermidis to Acrylic and Silicone

PubMed Central

Sousa, Cláudia; Teixeira, Pilar; Oliveira, Rosário

2009-01-01

The aim of the present study was to compare the ability of eight Staphylococcus epidermidis strains to adhere to acrylic and silicone, two polymers normally used in medical devices manufacture. Furthermore, it was tried to correlate that with the surface properties of substrata and cells. Therefore, hydrophobicity and surface tension components were calculated through contact angle measurements. Surface roughness of substrata was also assessed by atomic force microscopy (AFM). No relationship was found between microbial surface hydrophobicity and adhesion capability. Nevertheless, Staphylococcus epidermidis IE214 showed very unique adhesion behaviour, with cells highly aggregated between them, which is a consequence of their specific surface features. All strains, determined as being hydrophilic, adhered at a higher extent to silicone than to acrylic, most likely due to its more hydrophobic character and higher roughness. This demonstrates the importance of biomaterial surface characteristics for bacterial adhesion. PMID:20126579

Phenazine antibiotic inspired discovery of potent bromophenazine antibacterial agents against Staphylococcus aureus and Staphylococcus epidermidis.

PubMed

Borrero, Nicholas V; Bai, Fang; Perez, Cristian; Duong, Benjamin Q; Rocca, James R; Jin, Shouguang; Huigens, Robert W

2014-02-14

Nearly all clinically used antibiotics have been (1) discovered from microorganisms (2) using phenotype screens to identify inhibitors of bacterial growth. The effectiveness of these antibiotics is attributed to their endogenous roles as bacterial warfare agents against competing microorganisms. Unfortunately, every class of clinically used antibiotic has been met with drug resistant bacteria. In fact, the emergence of resistant bacterial infections coupled to the dismal pipeline of new antibacterial agents has resulted in a global health care crisis. There is an urgent need for innovative antibacterial strategies and treatment options to effectively combat drug resistant bacterial pathogens. Here, we describe the implementation of a Pseudomonas competition strategy, using redox-active phenazines, to identify novel antibacterial leads against Staphylococcus aureus and Staphylococcus epidermidis. In this report, we describe the chemical synthesis and evaluation of a diverse 27-membered phenazine library. Using this microbial warfare inspired approach, we have identified several bromophenazines with potent antibacterial activities against S. aureus and S. epidermidis. The most potent bromophenazine analogue from this focused library demonstrated a minimum inhibitory concentration (MIC) of 0.78-1.56 μM, or 0.31-0.62 μg mL(-1), against S. aureus and S. epidermidis and proved to be 32- to 64-fold more potent than the phenazine antibiotic pyocyanin in head-to-head MIC experiments. In addition to the discovery of potent antibacterial agents against S. aureus and S. epidermidis, we also report a detailed structure-activity relationship for this class of bromophenazine small molecules.

Staphylococcus epidermidis strains isolated from breast milk of women suffering infectious mastitis: potential virulence traits and resistance to antibiotics.

PubMed

Delgado, Susana; Arroyo, Rebeca; Jiménez, Esther; Marín, Maria L; del Campo, Rosa; Fernández, Leonides; Rodríguez, Juan M

2009-05-07

Although Staphylococcus aureus is considered the main etiological agent of infectious mastitis, recent studies have suggested that coagulase-negative staphylococci (CNS) may also play an important role in such infections. The aims of this work were to isolate staphylococci from milk of women with lactational mastitis, to select and characterize the CNS isolates, and to compare such properties with those displayed by CNS strains isolated from milk of healthy women. The milk of 30 women was collected and bacterial growth was noted in 27 of them, of which Staphylococcus epidermidis was isolated from 26 patients and S. aureus from 8. Among the 270 staphylococcal isolates recovered from milk of women with mastitis, 200 were identified as Staphylococcus epidermidis by phenotypic assays, species-specific PCR and PCR sequencing. They were typified by pulsed field gel electrophoresis (PFGE) genotyping. The PFGE profiles of the S. epidermidis strains were compared with those of 105 isolates from milk of healthy women. A representative of the 76 different PFGE profiles was selected to study the incidence of virulence factors and antibiotic resistance. The number of strains that contained the biofilm-related icaD gene and that showed resistance to oxacillin, erythromycin, clindamycin and mupirocin was significantly higher among the strains isolated from mastitic milk. S. epidermidis may be a frequent but largely underrated cause of infectious mastitis in lactating women. The resistance to diverse antibiotics and a higher ability to form biofilms found among the strains isolated from milk of women suffering mastitis may explain the chronic and/or recurrent nature of this infectious condition.

Evaluation of Anti-inflammatory and Antimicrobial Activity of AHPL/AYCAP/0413 Capsule.

PubMed

Nipanikar, Sanjay; Chitlange, Sohan; Nagore, Dheeraj

2017-01-01

Conventional therapeutic agents used for treatment of Acne are associated with various adverse effects necessitating development of safe and effective alternative therapeutic agents. In this context, a polyherbal formulation AHPL/AYCAP/0413 was developed for treatment of Acne. To evaluate Anti-inflammatory and antimicrobial activity of AHPL/AYCAP/0413. 1) Anti-inflammatory activity: Anti-inflammatory activity of AHPL/AYCAP/0413 in comparison with Diclofenac was assessed in carrageenan induced rat Paw edema model. 2) Anti-microbial activity for P. acne : Propionibacterium acnes were incubated under anaerobic conditions. Aliquots of molten BHI with glucose agar were used as the agar base. Formulation and clindamycin (10 μg/ml) were introduced in to the Agar wells randomly. 3) Anti-microbial activity for Staphylococcus epidermidis and Staphylococcus aureus : Staphylococcus epidermidis and Staphylococcus aureus were incubated under aerobic conditions at 37°C. TSB with glucose agar was used as the agar base. 0.5ml of formulation and clindamycin (10 μg/ml) were introduced in to the wells randomly. The antibacterial activity was evaluated by measuring zones of inhibition (in mm). Significant reduction in rat paw edema (51% inhibition) was observed with formulation AHPL/AYCAP/0413 which was also comparable to that of Diclofenac (58% inhibition). Zone of inhibition for formulation was 18.33 mm, 19.20 mm and 26.30 mm for P. acnes , S. epidermidis and S. aureus respectively. This activity was also comparable to that of Clindamycin. AHPL/AYCAP/0413 capsule possesses significant Anti-inflammatory and Anti-microbial activities which further justifies its role in the management of Acne vulgaris. Anti-inflammatory and antimicrobial activities of polyherbal formulation AHPL/AYCAP/0413 were evaluatedAHPL/AYCAP/0413 contains Guduchi extract ( Tinospora cordifolia ), Manjishtha extract ( Rubia cordifolia ), Sariva extract ( Hemidesmus indicus ), Nimba extract ( Azardirachta indica ), Khadira extract ( Acacia catechu ) and Kakmachi extract ( Solanum nigrum )Anti-inflammatory activity of AHPL/AYCAP/0413 in comparison with Diclofenac was assessed in carrageenan induced rat Paw edema model. Significant reduction in rat paw edema (51% inhibition) was observed with formulation AHPL/AYCAP/0413 which was also comparable to that of Diclofenac (58% inhibition)Anti-microbial activity of AHPL/AYCAP/0413 was assessed against Propionibacterium acnes , Staphylococcus epidermidis and Staphylococcus aureus . Zone of inhibition for formulation was 18.33 mm, 19.20 mm and 26.30 mm for P. acnes , S. epidermidis and S. aureus respectively indicating 68.42%, 85.71% and 81.17% activity. This activity was also comparable to that of ClindamycinTherefore it is evident that, AHPL/AYCAP/0413 capsule possesses significant Anti-inflammatory and Anti-microbial activities which further justifies its role in the management of Acne vulgaris. Abbreviations Used : mg: Milligram, kg: Kilogram, w/v: Weight by volume, ml: Milliliters, h: Hour, BHI: Brain Heart Infusion, CFU: Colony forming units, μg: Microgram, A.I.: Activity index, P.I.: Percent inhibition, TSB: Trypticsoy Broth, mm: millimeters, P. acnes : Propionibacterium acnes , S. epidermidis : Staphylococcus epidermidis, S. aureus : Staphylococcus aureus.

Antimicrobial efficacy and aqueous humor concentration of preoperative and postoperative topical trimethoprim/polymyxin B sulfate versus tobramycin.

PubMed

Osher, R H; Amdahl, L D; Cheetham, J K

1994-01-01

We compared trimethoprim sulfate 0.1%/polymyxin B sulfate 10,000 units/mL with tobramycin 0.3% for preoperative sterilization of the ocular surface, aqueous humor concentration, and ocular safety and comfort in 99 patients who had cataract extraction and intraocular lens implantation. The organisms most frequently cultured from the conjunctiva at baseline were Staphylococcus epidermidis, Corynebacterium species, and Staphylococcus aureus, which were isolated from 66%, 15%, and 8% of the 95 specimens eligible for evaluation. All organisms identified in positive baseline conjunctival cultures except Staphylococcus epidermidis were completely eradicated in both groups on the day of surgery and five to seven days postoperatively. Staphylococcus epidermidis was eradicated on the day of surgery in 58% of patients in the trimethoprim/polymyxin group and in 68% in the tobramycin group. This organism was eradicated five to seven days postoperatively in 85% of patients in both groups. Mean aqueous humor concentration of trimethoprim sulfate at surgery was greater than the mean tobramycin concentration, but neither reached clinically significant inhibitory levels for most organisms. No significant differences were found in ocular safety and comfort.

Synergy between antibiotics and natural agents results in increased antimicrobial activity against Staphylococcus epidermidis.

PubMed

Abidi, Syed Hani; Ahmed, Khalid; Sherwani, Sikander Khan; Kazmi, Shahana Urooj

2015-09-27

Staphylococcus epidermidis is one of the most frequent causes of biofilm-associated infections on indwelling medical devices. With the emergence of methicillin-resistant S. epidermidis (MRSE), there is an urgent need to discover novel active agents against a range of Gram-positive pathogens. We screened the clinical isolates of S. epidermidis for susceptibility/resistance against commonly prescribed antibiotics. Furthermore, we tested some natural agents alone and in combination with antibiotics to find possible synergistic antimicrobial effects. S. epidermidis clinical isolates were screened for susceptibility/resistance against vancomycin, erythromycin, tetracycline, chloramphenicol, ampicillin, ofloxacin, cephalexin, and gentamicin using the Kirby-Bauer disk diffusion method. The antimicrobial potential of Camellia sinensis, Juglans regia, and Hippophae rhamnoides alone and in combination with antibiotics were examined using the disk diffusion method, where the antimicrobial potential activity was measured in terms of formation of zones of inhibition. Most S. epidermidis isolates were found to be resistant to one or more antibiotics. Gentamycin and ofloxacin were found to be the most effective antibiotics against S. epidermidis isolates. Extracts of Hippophae rhamnoides, Juglans regia, and Camellia sinensis were found to be equally effective against S. epidermidis isolates. In combination with antibiotics, these extracts exhibited appreciable synergistic activity; the highest synergistic activity was observed with erythromycin and cephalexin. In the case of cephalexin, a reversion in resistance was observed. The plant extracts used in the study exhibited additive and synergistic antibacterial activity against S. epidermidis, hence providing an effective alternative to deal with the problem of multidrug resistance.

Extracellular DNA Impedes the Transport of Vancomycin in Staphylococcus epidermidis Biofilms Preexposed to Subinhibitory Concentrations of Vancomycin

PubMed Central

Tseng, Boo Shan; Howlin, Robert P.; Deacon, Jill; Wharton, Julian A.; Thurner, Philipp J.; Gilmore, Brendan F.; Parsek, Matthew R.; Stoodley, Paul

2014-01-01

Staphylococcus epidermidis biofilm formation is responsible for the persistence of orthopedic implant infections. Previous studies have shown that exposure of S. epidermidis biofilms to sub-MICs of antibiotics induced an increased level of biofilm persistence. BODIPY FL-vancomycin (a fluorescent vancomycin conjugate) and confocal microscopy were used to show that the penetration of vancomycin through sub-MIC-vancomycin-treated S. epidermidis biofilms was impeded compared to that of control, untreated biofilms. Further experiments showed an increase in the extracellular DNA (eDNA) concentration in biofilms preexposed to sub-MIC vancomycin, suggesting a potential role for eDNA in the hindrance of vancomycin activity. Exogenously added, S. epidermidis DNA increased the planktonic vancomycin MIC and protected biofilm cells from lethal vancomycin concentrations. Finally, isothermal titration calorimetry (ITC) revealed that the binding constant of DNA and vancomycin was 100-fold higher than the previously reported binding constant of vancomycin and its intended cellular d-Ala-d-Ala peptide target. This study provides an explanation of the eDNA-based mechanism of antibiotic tolerance in sub-MIC-vancomycin-treated S. epidermidis biofilms, which might be an important factor for the persistence of biofilm infections. PMID:25267673

Slime-producing Staphylococcus epidermidis and S. aureus in acute bacterial conjunctivitis in soft contact lens wearers.

PubMed

Catalanotti, Piergiorgio; Lanza, Michele; Del Prete, Antonio; Lucido, Maria; Catania, Maria Rosaria; Gallè, Francesca; Boggia, Daniela; Perfetto, Brunella; Rossano, Fabio

2005-10-01

In recent years, an increase in ocular pathologies related to soft contact lens has been observed. The most common infectious agents were Staphylococcus spp. Some strains produce an extracellular polysaccharidic slime that can cause severe infections. Polysaccharide synthesis is under genetic control and involves a specific intercellular adhesion (ica) locus, in particular, icaA and icaD genes. Conjunctival swabs from 97 patients with presumably bacterial bilateral conjunctivitis, wearers of soft contact lenses were examined. We determined the ability of staphylococci to produce slime, relating it to the presence of icaA and icaD genes. We also investigated the antibiotic susceptibility and Pulsed Field Gel Electrophoresis (PFGE) patterns of the clinical isolates. We found that 74.1% of the S. epidermidis strains and 61.1% of the S. aureus strains isolated were slime producers and showed icaA and icaD genes. Both S. epidermidis and S. aureus slime-producing strains exhibited more surface hydrophobicity than non-producing slime strains. The PFGE patterns overlapped in S. epidermidis strains with high hydrophobicity. The similar PFGE patterns were not related to biofilm production. We found scarce matching among the Staphylococcus spp. studied, slime production, surface hydrophobicity and antibiotic susceptibility.

Cultivation of Staphylococcus epidermidis in the Human Spaceflight Environment Leads to Alterations in the Frequency and Spectrum of Spontaneous Rifampicin-Resistance Mutations in the rpoB Gene

PubMed Central

Fajardo-Cavazos, Patricia; Nicholson, Wayne L.

2016-01-01

Bacteria of the genus Staphylococcus are persistent inhabitants of human spaceflight habitats and represent potential opportunistic pathogens. The effect of the human spaceflight environment on the growth and the frequency of mutations to antibiotic resistance in the model organism Staphylococcus epidermidis strain ATCC12228 was investigated. Six cultures of the test organism were cultivated in biological research in canisters–Petri dish fixation units for 122 h on orbit in the International Space Station (ISS) as part of the SpaceX-3 resupply mission. Asynchronous ground controls (GCs) consisted of identical sets of cultures cultivated for 122 h in the ISS Environmental Simulator at Kennedy Space Center. S. epidermidis exhibited significantly lower viable counts but significantly higher frequencies of mutation to rifampicin (Rif) resistance in space vs. GC cultures. The spectrum of mutations in the rpoB gene leading to RifR was altered in S. epidermidis isolates cultivated in the ISS compared to GCs. The results suggest that the human spaceflight environment induces unique physiologic stresses on growing bacterial cells leading to changes in mutagenic potential. PMID:27446039

Cultivation of Staphylococcus epidermidis in the Human Spaceflight Environment Leads to Alterations in the Frequency and Spectrum of Spontaneous Rifampicin-Resistance Mutations in the rpoB Gene.

PubMed

Fajardo-Cavazos, Patricia; Nicholson, Wayne L

2016-01-01

Bacteria of the genus Staphylococcus are persistent inhabitants of human spaceflight habitats and represent potential opportunistic pathogens. The effect of the human spaceflight environment on the growth and the frequency of mutations to antibiotic resistance in the model organism Staphylococcus epidermidis strain ATCC12228 was investigated. Six cultures of the test organism were cultivated in biological research in canisters-Petri dish fixation units for 122 h on orbit in the International Space Station (ISS) as part of the SpaceX-3 resupply mission. Asynchronous ground controls (GCs) consisted of identical sets of cultures cultivated for 122 h in the ISS Environmental Simulator at Kennedy Space Center. S. epidermidis exhibited significantly lower viable counts but significantly higher frequencies of mutation to rifampicin (Rif) resistance in space vs. GC cultures. The spectrum of mutations in the rpoB gene leading to Rif(R) was altered in S. epidermidis isolates cultivated in the ISS compared to GCs. The results suggest that the human spaceflight environment induces unique physiologic stresses on growing bacterial cells leading to changes in mutagenic potential.

Pathogenic Mechanisms and Host Interactions in Staphylococcus epidermidis Device-Related Infection.

PubMed

Sabaté Brescó, Marina; Harris, Llinos G; Thompson, Keith; Stanic, Barbara; Morgenstern, Mario; O'Mahony, Liam; Richards, R Geoff; Moriarty, T Fintan

2017-01-01

Staphylococcus epidermidis is a permanent member of the normal human microbiota, commonly found on skin and mucous membranes. By adhering to tissue surface moieties of the host via specific adhesins, S. epidermidis is capable of establishing a lifelong commensal relationship with humans that begins early in life. In its role as a commensal organism, S. epidermidis is thought to provide benefits to human host, including out-competing more virulent pathogens. However, largely due to its capacity to form biofilm on implanted foreign bodies, S. epidermidis has emerged as an important opportunistic pathogen in patients receiving medical devices. S. epidermidis causes approximately 20% of all orthopedic device-related infections (ODRIs), increasing up to 50% in late-developing infections. Despite this prevalence, it remains underrepresented in the scientific literature, in particular lagging behind the study of the S. aureus . This review aims to provide an overview of the interactions of S. epidermidis with the human host, both as a commensal and as a pathogen. The mechanisms retained by S. epidermidis that enable colonization of human skin as well as invasive infection, will be described, with a particular focus upon biofilm formation. The host immune responses to these infections are also described, including how S. epidermidis seems to trigger low levels of pro-inflammatory cytokines and high levels of interleukin-10, which may contribute to the sub-acute and persistent nature often associated with these infections. The adaptive immune response to S. epidermidis remains poorly described, and represents an area which may provide significant new discoveries in the coming years.

A Precision Microbiome Approach Using Sucrose for Selective Augmentation of Staphylococcus epidermidis Fermentation against Propionibacterium acnes

PubMed Central

Wang, Yanhan; Kao, Ming-Shan; Yu, Jinghua; Huang, Stephen; Marito, Shinta; Gallo, Richard L.; Huang, Chun-Ming

2016-01-01

Acne dysbiosis happens when there is a microbial imbalance of the over-growth of Propionibacterium acnes (P. acnes) in the acne microbiome. In our previous study, we demonstrated that Staphylococcus epidermidis (S. epidermidis, a probiotic skin bacterium) can exploit glycerol fermentation to produce short-chain fatty acids (SCFAs) which have antimicrobial activities to suppress the growth of P. acnes. Unlike glycerol, sucrose is chosen here as a selective fermentation initiator (SFI) that can specifically intensify the fermentation activity of S. epidermidis, but not P. acnes. A co-culture of P. acnes and fermenting S. epidermidis in the presence of sucrose significantly led to a reduction in the growth of P. acnes. The reduction was abolished when P. acnes was co-cultured with non-fermenting S. epidermidis. Results from nuclear magnetic resonance (NMR) analysis revealed four SCFAs (acetic acid, butyric acid, lactic acid, and succinic acid) were detectable in the media of S. epidermidis sucrose fermentation. To validate the interference of S. epidermidis sucrose fermentation with P. acnes, mouse ears were injected with both P. acnes and S. epidermidis plus sucrose or phosphate buffered saline (PBS). The level of macrophage-inflammatory protein-2 (MIP-2) and the number of P. acnes in ears injected with two bacteria plus sucrose were considerably lower than those in ears injected with two bacteria plus PBS. Our results demonstrate a precision microbiome approach by using sucrose as a SFI for S. epidermidis, holding future potential as a novel modality to equilibrate dysbiotic acne. PMID:27834859

A Precision Microbiome Approach Using Sucrose for Selective Augmentation of Staphylococcus epidermidis Fermentation against Propionibacterium acnes.

PubMed

Wang, Yanhan; Kao, Ming-Shan; Yu, Jinghua; Huang, Stephen; Marito, Shinta; Gallo, Richard L; Huang, Chun-Ming

2016-11-09

Acne dysbiosis happens when there is a microbial imbalance of the over-growth of Propionibacterium acne s ( P. acnes ) in the acne microbiome. In our previous study, we demonstrated that Staphylococcus epidermidis ( S. epidermidis , a probiotic skin bacterium) can exploit glycerol fermentation to produce short-chain fatty acids (SCFAs) which have antimicrobial activities to suppress the growth of P. acnes . Unlike glycerol, sucrose is chosen here as a selective fermentation initiator (SFI) that can specifically intensify the fermentation activity of S. epidermidis , but not P. acnes . A co-culture of P. acnes and fermenting S. epidermidis in the presence of sucrose significantly led to a reduction in the growth of P. acnes . The reduction was abolished when P. acnes was co-cultured with non-fermenting S. epidermidis . Results from nuclear magnetic resonance (NMR) analysis revealed four SCFAs (acetic acid, butyric acid, lactic acid, and succinic acid) were detectable in the media of S. epidermidis sucrose fermentation. To validate the interference of S. epidermidis sucrose fermentation with P. acnes , mouse ears were injected with both P. acnes and S. epidermidis plus sucrose or phosphate buffered saline (PBS). The level of macrophage-inflammatory protein-2 (MIP-2) and the number of P. acnes in ears injected with two bacteria plus sucrose were considerably lower than those in ears injected with two bacteria plus PBS. Our results demonstrate a precision microbiome approach by using sucrose as a SFI for S. epidermidis , holding future potential as a novel modality to equilibrate dysbiotic acne.

Molecular epidemiology of coagulase-negative bloodstream isolates: detection of Staphylococcus epidermidis ST2, ST7 and linezolid-resistant ST23.

PubMed

Martínez-Meléndez, Adrián; Morfín-Otero, Rayo; Villarreal-Treviño, Licet; Camacho-Ortíz, Adrián; González-González, Gloria; Llaca-Díaz, Jorge; Rodríguez-Noriega, Eduardo; Garza-González, Elvira

2016-01-01

The mechanisms contributing to persistence of coagulase-negative staphylococci are diverse; to better understanding of their dynamics, the characterization of nosocomial isolates is needed. Our aim was to characterize phenotypic and molecular characteristics of Staphylococcus epidermidis and Staphylococcus haemolyticus human blood isolates from two tertiary care hospitals in Mexico, the Hospital Universitario in Monterrey and the Hospital Civil in Guadalajara. Antimicrobial susceptibility was determined. Biofilm formation was assessed by crystal violet staining. Detection of the ica operon and Staphylococcal Cassette Chromosome mec typing were performed by PCR. Clonal relatedness was determined by Pulsed-fiel gel electrophoresis and Multi locus sequence typing. Methicillin-resistance was 85.5% and 93.2% for S. epidermidis and S. haemolyticus, respectively. Both species showed resistance >70% to norfloxacin, clindamycin, levofloxacin, trimethoprim/sulfamethoxazole, and erythromycin. Three S. epidermidis and two S. haemolyticus isolates were linezolid-resistant (one isolate of each species was cfr+). Most isolates of both species were strong biofilm producers (92.8% of S. epidermidis and 72.9% of S. haemolyticus). The ica operon was amplified in 36 (43.4%) S. epidermidis isolates. SCCmec type IV was found in 47.2% of the S. epidermidis isolates and SCCmec type V in 14.5% of S. haemolyticus isolates. No clonal relatedness was found in either species. Resistance to clindamycin, levofloxacin, erythromycin, oxacillin, and cefoxitin was associated with biofilm production for both species (p<0.05). A G2576T mutation in 23S rRNA gene was detected in an S. haemolyticus linezolid-resistant isolate. All linezolid-resistant S. epidermidis isolates belonged to ST23; isolate with SCCmec type IV belonged to ST7, and isolate with SCCmec type III belonged to ST2. This is the first report of ST7 in Mexico. There was a high genetic diversity in both species, though both species shared characteristics that may contibute to virulence. Copyright © 2016 Elsevier Editora Ltda. All rights reserved.

Genotypes, antibiotic resistance, and virulence factors of staphylococci from ready-to-eat food.

PubMed

Podkowik, Magdalena; Bystroń, Jarosław; Bania, Jacek

2012-01-01

Sixty-seven staphylococcal isolates belonging to 12 species were obtained from 70 ready-to-eat food products. Staphylococcus aureus (n=25), and Staphylococcus epidermidis (n=13) were dominant. Susceptibility to penicillin, oxacillin, tetracycline, clindamycin, gentamicin, erythromycin, ciprofloxacin, and vancomycin was determined. All investigated S. aureus isolates were resistant to at least one antibiotic, and fifteen isolates were resistant to four and more antibiotics. Thirty-eight coagulase-negative staphylococci (CNS) isolates were resistant to at least one antibiotic, and seventeen to four and more antibiotics. Fifteen CNS isolates were mecA positive, and grew in the presence of 6 μg/mL oxacillin. All S. aureus isolates were mecA-negative. Arginine catabolic mobile element (ACME) was found in seven S. epidermidis isolates. Five S. epidermidis isolates harbored ica operon, ACME and were able to form biofilm. Three of them also possessed IS256 element and were mecA-positive. The expression of icaA gene was comparable in five ica-positive S. epidermidis isolates. One of six mecA positive S. epidermidis isolates was classified as sequence type (ST)155, one as ST110, and two as ST88. Two methicillin-resistant Staphylococcus epidermis (MRSE) belonged to new STs, that is, ST362, and ST363. Enterotoxin genes were found in 92% of S. aureus isolates. No enterotoxin gene was detected in analyzed CNS population. We show that ready-to-eat products are an important source of antibiotic-resistant CNS and potentially virulent strains of S. epidermidis, including genotypes undistinguishable from hospital-adapted clones.

Metabolism of azo dyes by human skin microbiota

PubMed Central

Stingley, Robin L.; Zou, Wen; Heinze, Thomas M.; Chen, Huizhong; Cerniglia, Carl E.

2018-01-01

Reduction of Methyl Red (MR) and Orange II (Or II) by 26 human skin bacterial species was monitored by a rapid spectrophotometric assay. The analysis indicated that skin bacteria, representing the genera Staphylococcus, Corynebacterium, Micrococcus, Dermacoccus and Kocuria, were able to reduce MR by 74–100 % in 24 h, with only three species unable to reduce completely the dye in that time. Among the species tested, only Corynebacterium xerosis was unable to reduce Or II to any degree by 24 h, and only Staphylococcus delphini, Staphylococcus sciuri subsp. sciuri and Pseudomonas aeruginosa were able to reduce completely this dye within 24 h. MR reduction started with early-exponential growth in Staphylococcus aureus and Staphylococcus epidermidis, and around late-exponential/early-stationary growth in P. aeruginosa. Reduction of Or II, Ponceau S and Ponceau BS started during late-exponential/early-stationary growth for all three species. Using liquid chromatography/electrospray ionization mass spectrometry analyses, MR metabolites produced by Staph. aureus, Staph. epidermidis and P. aeruginosa were identified as N,N-dimethyl-p-phenylenediamine and 2-aminobenzoic acid. Searches of available genomic and proteomic data revealed that at least four of the staphylococci in this study, Staphylococcus haemolyticus, Staph. epidermidis, Staphylococcus cohnii and Staphylococcus saprophyticus, have hypothetical genes with 77, 76, 75 and 74 % sequence identity to azo1 encoding an azoreductase from Staph. aureus and hypothetical proteins with 82, 80, 72 and 74 % identity to Azo1, respectively. In addition, Staphylococcus capitis has a protein with 79 % identity to Azo1. Western analysis detected proteins similar to Azo1 in all the staphylococci tested, except Staph. delphini, Staph. sciuri subsp. sciuri and Staphylococcus auricularis. The data presented in this report will be useful in the risk assessment process for evaluation of public exposure to products containing these dyes. PMID:19729456

Metabolism of azo dyes by human skin microbiota.

PubMed

Stingley, Robin L; Zou, Wen; Heinze, Thomas M; Chen, Huizhong; Cerniglia, Carl E

2010-01-01

Reduction of Methyl Red (MR) and Orange II (Or II) by 26 human skin bacterial species was monitored by a rapid spectrophotometric assay. The analysis indicated that skin bacteria, representing the genera Staphylococcus, Corynebacterium, Micrococcus, Dermacoccus and Kocuria, were able to reduce MR by 74-100 % in 24 h, with only three species unable to reduce completely the dye in that time. Among the species tested, only Corynebacterium xerosis was unable to reduce Or II to any degree by 24 h, and only Staphylococcus delphini, Staphylococcus sciuri subsp. sciuri and Pseudomonas aeruginosa were able to reduce completely this dye within 24 h. MR reduction started with early-exponential growth in Staphylococcus aureus and Staphylococcus epidermidis, and around late-exponential/early-stationary growth in P. aeruginosa. Reduction of Or II, Ponceau S and Ponceau BS started during late-exponential/early-stationary growth for all three species. Using liquid chromatography/electrospray ionization mass spectrometry analyses, MR metabolites produced by Staph. aureus, Staph. epidermidis and P. aeruginosa were identified as N,N-dimethyl-p-phenylenediamine and 2-aminobenzoic acid. Searches of available genomic and proteomic data revealed that at least four of the staphylococci in this study, Staphylococcus haemolyticus, Staph. epidermidis, Staphylococcus cohnii and Staphylococcus saprophyticus, have hypothetical genes with 77, 76, 75 and 74 % sequence identity to azo1 encoding an azoreductase from Staph. aureus and hypothetical proteins with 82, 80, 72 and 74 % identity to Azo1, respectively. In addition, Staphylococcus capitis has a protein with 79 % identity to Azo1. Western analysis detected proteins similar to Azo1 in all the staphylococci tested, except Staph. delphini, Staph. sciuri subsp. sciuri and Staphylococcus auricularis. The data presented in this report will be useful in the risk assessment process for evaluation of public exposure to products containing these dyes.

Silver-nanoparticles-modified biomaterial surface resistant to staphylococcus: new insight into the antimicrobial action of silver

PubMed Central

Wang, Jiaxing; Li, Jinhua; Guo, Geyong; Wang, Qiaojie; Tang, Jin; Zhao, Yaochao; Qin, Hui; Wahafu, Tuerhongjiang; Shen, Hao; Liu, Xuanyong; Zhang, Xianlong

2016-01-01

Titanium implants are widely used clinically, but postoperative implant infection remains a potential severe complication. The purpose of this study was to investigate the antibacterial activity of nano-silver(Ag)-functionalized Ti surfaces against epidemic Staphylococcus from the perspective of the regulation of biofilm-related genes and based on a bacteria-cell co-culture study. To achieve this goal, two representative epidemic Staphylococcus strains, Staphylococcus epidermidis (S. epidermidis, RP62A) and Staphylococcus aureus (S. aureus, USA 300), were used, and it was found that an Ag-nanoparticle-modified Ti surface could regulate the expression levels of biofilm-related genes (icaA and icaR for S. epidermidis; fnbA and fnbB for S. aureus) to inhibit bacterial adhesion and biofilm formation. Moreover, a novel bacteria-fibroblast co-culture study revealed that the incorporation of Ag nanoparticles on such a surface can help mammalian cells to survive, adhere and spread more successfully than Staphylococcus. Therefore, the modified surface was demonstrated to possess a good anti-infective capability against both sessile bacteria and planktonic bacteria through synergy between the effects of Ag nanoparticles and ion release. This work provides new insight into the antimicrobial action and mechanism of Ag-nanoparticle-functionalized Ti surfaces with bacteria-killing and cell-assisting capabilities and paves the way towards better satisfying the clinical needs. PMID:27599568

Poly-N-Acetylglucosamine Production by Staphylococcus epidermidis Cells Increases Their In Vivo Proinflammatory Effect

PubMed Central

Ferreirinha, Pedro; Pérez-Cabezas, Begoña; Correia, Alexandra; Miyazawa, Bruna; França, Angela; Carvalhais, Virgínia; Faustino, Augusto; Cordeiro-da-Silva, Anabela; Teixeira, Luzia; Pier, Gerald B.

2016-01-01

Poly-N-acetylglucosamine (PNAG) is a major component of the Staphylococcus epidermidis biofilm extracellular matrix. However, it is not yet clear how this polysaccharide impacts the host immune response and infection-associated pathology. Faster neutrophil recruitment and bacterial clearance were observed in mice challenged intraperitoneally with S. epidermidis biofilm cells of the PNAG-producing 9142 strain than in mice similarly challenged with the isogenic PNAG-defective M10 mutant. Moreover, intraperitoneal priming with 9142 cells exacerbated liver inflammatory pathology induced by a subsequent intravenous S. epidermidis challenge, compared to priming with M10 cells. The 9142-primed mice had elevated splenic CD4+ T cells producing gamma interferon and interleukin-17A, indicating that PNAG promoted cell-mediated immunity. Curiously, despite having more marked liver tissue pathology, 9142-primed mice also had splenic T regulatory cells with greater suppressive activity than those of their M10-primed counterparts. By showing that PNAG production by S. epidermidis biofilm cells exacerbates host inflammatory pathology, these results together suggest that this polysaccharide contributes to the clinical features associated with biofilm-derived infections. PMID:27481237

Effect of Antimicrobial and Physical Treatments on Growth of Multispecies Staphylococcal Biofilms

PubMed Central

Payne, David E.; Ma, Tianhui Maria; VanEpps, J. Scott; Boles, Blaise R.; Younger, John G.

2017-01-01

ABSTRACT The prevalence and structure of Staphylococcus aureus and Staphylococcus epidermidis within multispecies biofilms were found to depend sensitively on physical environment and antibiotic dosage. Although these species commonly infect similar sites, such as orthopedic implants, little is known about their behavior in multispecies communities, particularly in response to treatment. This research establishes that S. aureus is much more prevalent than S. epidermidis when simultaneously seeded and grown under unstressed conditions (pH 7, 37°C) in both laboratory and clinical strains. In multispecies communities, S. epidermidis is capable of growing a more confluent biofilm when the addition of S. aureus is delayed 4 to 6 h during 18 h of growth. Different vancomycin dosages generate various behaviors: S. epidermidis is more prevalent at a dose of 1.0 μg/ml vancomycin, but reduced growth of both species occurs at 1.9 μg/ml vancomycin. This variability is consistent with the different MICs of S. aureus and S. epidermidis. Growth at higher temperature (45°C) results in an environment where S. aureus forms porous biofilms. This porosity allows S. epidermidis to colonize more of the surface, resulting in detectable S. epidermidis biomass. Variations in pH result in increased prevalence of S. epidermidis at low pH (pH 5 and 6), while S. aureus remains dominant at high pH (pH 8 and 9). This work establishes the structural variability of multispecies staphylococcal biofilms as they undergo physical and antimicrobial treatments. It provides a basis for understanding the structure of these communities at infection sites and how treatments disrupt their multispecies behaviors. IMPORTANCE Staphylococcus aureus and Staphylococcus epidermidis are two species of bacteria that are commonly responsible for biofilm infections on medical devices. Biofilms are structured communities of bacteria surrounded by polysaccharides, proteins, and DNA; bacteria are more resistant to antimicrobials as part of a biofilm than as individual cells. This work investigates the structure and prevalence of these two organisms when grown together in multispecies biofilms and shows shifts in the behavior of the polymicrobial community when grown in various concentrations of vancomycin (an antibiotic commonly used to treat staphylococcal infections), in a high-temperature environment (a condition previously shown to lead to cell disruption and death), and at low and high pH (a change that has been previously shown to soften the mechanical properties of staphylococcal biofilms). These shifts in community structure demonstrate the effect such treatments may have on multispecies staphylococcal infections. PMID:28411222

Effect of Antimicrobial and Physical Treatments on Growth of Multispecies Staphylococcal Biofilms.

PubMed

Stewart, Elizabeth J; Payne, David E; Ma, Tianhui Maria; VanEpps, J Scott; Boles, Blaise R; Younger, John G; Solomon, Michael J

2017-06-15

The prevalence and structure of Staphylococcus aureus and Staphylococcus epidermidis within multispecies biofilms were found to depend sensitively on physical environment and antibiotic dosage. Although these species commonly infect similar sites, such as orthopedic implants, little is known about their behavior in multispecies communities, particularly in response to treatment. This research establishes that S. aureus is much more prevalent than S. epidermidis when simultaneously seeded and grown under unstressed conditions (pH 7, 37°C) in both laboratory and clinical strains. In multispecies communities, S. epidermidis is capable of growing a more confluent biofilm when the addition of S. aureus is delayed 4 to 6 h during 18 h of growth. Different vancomycin dosages generate various behaviors: S. epidermidis is more prevalent at a dose of 1.0 μg/ml vancomycin, but reduced growth of both species occurs at 1.9 μg/ml vancomycin. This variability is consistent with the different MICs of S. aureus and S. epidermidis Growth at higher temperature (45°C) results in an environment where S. aureus forms porous biofilms. This porosity allows S. epidermidis to colonize more of the surface, resulting in detectable S. epidermidis biomass. Variations in pH result in increased prevalence of S. epidermidis at low pH (pH 5 and 6), while S. aureus remains dominant at high pH (pH 8 and 9). This work establishes the structural variability of multispecies staphylococcal biofilms as they undergo physical and antimicrobial treatments. It provides a basis for understanding the structure of these communities at infection sites and how treatments disrupt their multispecies behaviors. IMPORTANCE Staphylococcus aureus and Staphylococcus epidermidis are two species of bacteria that are commonly responsible for biofilm infections on medical devices. Biofilms are structured communities of bacteria surrounded by polysaccharides, proteins, and DNA; bacteria are more resistant to antimicrobials as part of a biofilm than as individual cells. This work investigates the structure and prevalence of these two organisms when grown together in multispecies biofilms and shows shifts in the behavior of the polymicrobial community when grown in various concentrations of vancomycin (an antibiotic commonly used to treat staphylococcal infections), in a high-temperature environment (a condition previously shown to lead to cell disruption and death), and at low and high pH (a change that has been previously shown to soften the mechanical properties of staphylococcal biofilms). These shifts in community structure demonstrate the effect such treatments may have on multispecies staphylococcal infections. Copyright © 2017 American Society for Microbiology.

[The evaluation of lipolytic activity of strains of Staphylococcus epidermidis and Staphylococcus haemolyticus].

PubMed

Wróblewska, Joanna; Sekowska, Alicja; Zalas-Wiecek, Patrycja; Gospodarek, Eugenia

2011-01-01

A total of 103 isolates of CNS (66 strains of S. epidermidis and 37 strains of S. haemolyticus) were investigated. Lipolytic activity of staphylococcal strains was determined by Tryptic Soy Agar containing Tween 20 or Tween 60. The 95.4% strains of staphylococci demonstrated the lipolytic activity on Tween 20 agar and the 89.4% of strains of staphylococci degradation ester of fatty acids on Tweens 60 agar. We detected that S. epidermidis strains (respectively 95,4%, 89,4%) produced lipases more frequently than S. haemolyticus strains (respectively 72,9%, 59,4%). Studies suggest that source of isolation from clinical materials (blood, wound and pus) does not have an influence on the ability hydrolysis esters.

Identification and characterization of methicillin-resistant Staphylococcus aureus, Staphylococcus epidermidis, Staphylococcus haemolyticus and Staphylococcus pettenkoferi from a small animal clinic.

PubMed

Weiss, Sonja; Kadlec, Kristina; Fessler, Andrea T; Schwarz, Stefan

2013-12-27

The aim of this study was to isolate and characterize methicillin-resistant staphylococci (MRS) in a small animal clinic and to investigate their distribution and possible transmission. Swabs (n=72) were taken from hospitalized pets, the environment and employees of a small animal clinic and screened for the presence of MRS. The staphylococcal species was confirmed biochemically or by 16S rDNA sequencing. Susceptibility to antimicrobial agents was tested by broth dilution. The presence of mecA and other resistance genes was confirmed by PCR. Molecular typing of the isolates followed standard procedures. In total, 34 MRS belonging to the four species Staphylococcus aureus (n=5), Staphylococcus epidermidis (n=21), Staphylococcus haemolyticus (n=6) or Staphylococcus pettenkoferi (n=2) were isolated. All isolates were multidrug-resistant with resistance to at least three classes of antimicrobial agents. Among the five methicillin-resistant S. aureus (MRSA) isolates, four belonged to the clonal complex CC398; two of them were isolated from cats, the remaining two from pet cages. Overall, the MRS isolates differed in their characteristics, except for one S. epidermidis clone (n=9) isolated from hospitalized cats without clinical staphylococcal infections, pet cages, the clinic environment as well as from a healthy employee. This MRSE clone was resistant to 10 classes of antimicrobial agents, including aminocyclitols, β-lactams, fluoroquinolones, lincosamides, macrolides, phenicols, pleuromutilins, sulfonamides, tetracyclines and trimethoprim. These findings suggest a possible transmission of specific MRS isolates between animal patients, employees and the clinic environment. Copyright © 2013 Elsevier B.V. All rights reserved.

Antimicrobial efficacy assessment of multi-use solution to disinfect hydrophilic contact lens, in vitro.

PubMed

Lui, Aline Cristina Fioravanti; Netto, Adamo Lui; Silva, Cely Barreto da; Hida, Richard; Mendes, Thais Sousa; Lui, Giovana Arlene Fioravanti; Gemperli, Daniela Barbosa; Vital, Enderson Dantas

2009-01-01

To evaluate the efficacy of disinfecting solutions in hydrophilic contact lenses (CL). Two multi-use solutions denominated solution A (0.001% polyquaternium-1 and 0.0005% myristamidopropyl dimethylamine) and solution B (0.0001% polyaminopropyl biguanide) were used. The solutions were tested in hydrophilic contact lenses infected with Pseudomonas aeruginosa (ATCC27583), Staphylococcus epidermidis (ATCC1226), Klebsiella pneumoniae (ATCC13883), Staphylococcus aureus (ATCC25923) and Candida albicans (ATCC 10231) and the decrease in microorganisms growth after the hydrophilic contact lenses were cleaned with the respective solutions was verified. The manufacture's instructions were followed. A decrease of 90% of Pseudomonas aeruginosa, Staphylococcus epidermidis, Staphylococcus aureus, Candida albicans and a decrease 100% of Klebsiella pneumoniae was observed. The solutions decreased the amount of microorganisms tested.

Genotype and enterotoxigenicity of Staphylococcus epidermidis isolate from ready to eat meat products

PubMed Central

Podkowik, Magdalena; Seo, Keun Seok; Schubert, Justyna; Tolo, Isaiah; Robinson, D. Ashley; Bania, Jacek; Bystroń, Jarosław

2016-01-01

We have previously shown that potentially pathogenic isolates of Staphylococcus epidermidis occur at high incidence in ready-to-eat food. Now, within 164 samples of ready-to-eat meat products we identified 32 S. epidermidis isolates. In 8 isolates we detected the genes encoding for staphylococcal enterotoxins, but in 7 S. epidermidis isolates these genes were not stable over passages. One isolate designated 4S was shown to stably harbour sec and sel genes.In the genome sequence of S. epidermidis 4S we identified 21,426-bp region flanked by direct-repeats, encompassing sec and sel genes, corresponding to the previously described composite staphylococcal pathogenicity island (SePI) in S. epidermidis FRI909. Alignment of S. epidermidis 4S and S. epidermidis FRI909 SePIs revealed 6 nucleotide mismatches located in 5 of the total of 29 ORFs. Genomic location of S. epidermidis 4S SePI was the same as in FRI909. S. epidermidis 4S is a single locus variant of ST561, being genetically different from FRI909. SECepi was secreted by S. epidermidis 4S to BHI broth ranging from 14 to almost 36 μg/mL, to milk ranging from 6-9 ng/mL, to beef meat juice from 2-3 μg/mL and to pork meat juice from 1-2 μg/mL after 24 and 48 hours of cultivation, respectively. We provide the first evidence that S. epidermidis occurring in food bears an element encoding an orthologue to S. aureus SEC, and that SECepi can be produced in microbial broth, milk and meat juices. Regarding that only enterotoxins produced by S. aureus are officially tracked in food in EU, the ability to produce enterotoxin by S. epidermidis pose real risk for food safety. PMID:27105039

[Comparison of induction L-form of Staphylococcus epidermidis, Staphylococcus haemolyticus by cefazolin].

PubMed

Wróblewska, Joanna; Gospodarek, Eugenia; Sekowska, Alicja; Mikołajczyk, Dorota; Janicka, Grazyna

2008-12-01

The L-forms of bacteria have not been studied carefully yet, because it is difficult to detect them in Gram stain reactions by light microscopy. They can be cultured on specialized hypertonic medium. We don't find any reports about intentional in vitro induction and assessment of frequency of L-forms of S. epidermidis and S. haemolyticus on the medium. to evaluate the frequency of induction of L-forms by Coagulase Negative Staphylococci. This thesis examines, if the source of isolation from clinical materials has an influence on the frequency of occurrence of cell-wall deficient bacteria. 52 strains of S. epidermidis, 52 strains of S. haemolyticus were analysed. After 13 S. epidermidis and S. haemolyticus strains were isolated from blood, urine, biomaterials, changed surface skin from patients of University Hospital in Bydgoszcz. S. epidermidis and S. haemolyticus strains were tested for induction of L-forms the methods of Owens (1988). It was observed that four (7.7%) strains of and S. haemolyticus transformed into L-forms. S. epidermidis strains isolated from blood induced L-forms (two strains), from urine and biomaterial (one strain). It was observed that strains of S. haemolyticus which have been isolated from blood and urine induced L-forms (three strains and one respectively). This study suggest that L-form induction in S. epidermidis and of S. haemolyticus strains is not correlated with sample origin from which the strains had been isolated. S. epidermidis and S. haemolyticus strains produce L-forms rarely.

Inferring a Population Structure for Staphylococcus epidermidis from Multilocus Sequence Typing Data▿

PubMed Central

Miragaia, M.; Thomas, J. C.; Couto, I.; Enright, M. C.; de Lencastre, H.

2007-01-01

Despite its importance as a human pathogen, information on population structure and global epidemiology of Staphylococcus epidermidis is scarce and the relative importance of the mechanisms contributing to clonal diversification is unknown. In this study, we addressed these issues by analyzing a representative collection of S. epidermidis isolates from diverse geographic and clinical origins using multilocus sequence typing (MLST). Additionally, we characterized the mobile element (SCCmec) carrying the genetic determinant of methicillin resistance. The 217 S. epidermidis isolates from our collection were split by MLST into 74 types, suggesting a high level of genetic diversity. Analysis of MLST data using the eBURST algorithm revealed the existence of nine epidemic clonal lineages that were disseminated worldwide. One single clonal lineage (clonal complex 2) comprised 74% of the isolates, whereas the remaining isolates were clustered into 8 minor clonal lineages and 13 singletons. According to our evolutionary model, SCCmec was acquired at least 56 times by S. epidermidis. Although geographic dissemination of S. epidermidis strains and the value of the index of association between the alleles, 0.2898 (P < 0.05), support the clonality of S. epidermidis species, examination of the sequence changes at MLST loci during clonal diversification showed that recombination gives rise to new alleles approximately twice as frequently as point mutations. We suggest that S. epidermidis has a population with an epidemic structure, in which nine clones have emerged upon a recombining background and evolved quickly through frequent transfer of genetic mobile elements, including SCCmec. PMID:17220222

Staphylococcus aureus and Staphylococcus epidermidis infections on implants.

PubMed

Oliveira, W F; Silva, P M S; Silva, R C S; Silva, G M M; Machado, G; Coelho, L C B B; Correia, M T S

2018-02-01

Infections are one of the main reasons for removal of implants from patients, and usually need difficult and expensive treatments. Staphylococcus aureus and Staphylococcus epidermidis are the most frequently detected pathogens. We reviewed the epidemiology and pathogenesis of implant-related infections. Relevant studies were identified by electronic searching of the following databases: PubMed, ScienceDirect, Academic Google, and CAPES Journal Portal. This review reports epidemiological studies of implant infections caused by S. aureus and S. epidermidis. We discuss some methodologies used in the search for new compounds with antibiofilm activity and the main strategies for biomaterial surface modifications to avoid bacterial plaque formation and consequent infection. S. aureus and S. epidermidis are frequently involved in infections in catheters and orthopaedic/breast implants. Different methodologies have been used to test the potential antibiofilm properties of compounds; for example, crystal violet dye is widely used for in-vitro biofilm quantification due to its low cost and good reproducibility. Changes in the surface biomaterials are necessary to prevent biofilm formation. Some studies have investigated the immobilization of antibiotics on the surfaces of materials used in implants. Other approaches have been used as a way to avoid the spread of bacterial resistance to antimicrobials, such as the functionalization of these surfaces with silver and natural compounds, as well as the electrical treatment of these substrates. Copyright © 2017 The Healthcare Infection Society. Published by Elsevier Ltd. All rights reserved.

[In vitro and in vivo activities of sulopenem compared with those of imipenem and cephalosporins].

PubMed

Nagashima, M; Goto, S; Yoshida, T; Matsunaga, T; Shimohira, H; Ogawa, M

1996-04-01

The in vitro and in vivo antibacterial activities of sulopenem (CP-70,429),a new parenteral penem antibiotic, were compared with those of imipenem (IPM), flomoxef, cefuzonam (CZON) and cefotaxime. Sulopenem possessed broad-spectrum activities against Gram-positive bacteria and Gram-negative bacteria. Antibacterial activities of sulopenem against methicillin-sensitive Staphylococcus aureus, Staphylococcus epidermidis, Enterococcus faecalis, Streptococcus pyogenes and Streptococcus pneumoniae were equivalent to or somewhat superior to those of IPM. Against members of the family Enterobacteriaceae, sulopenem was 4- to 260-fold more active than reference antibiotics with broad-spectra. In a killing kinetics study for Haemophilus influenzae, sulopenem showed a 99.9% decrease of viable cells after 8 hours at a concentration of 0.20 micrograms/ml. This effect was obtained at a concentration 8-fold lower than that of IPM. The protective effects of sulopenem in murine experimental systemic infections were superior to those of imipenem/cilastatin. In murine experimental mixed infection with Escherichia coli and Bacteroides fragilis, sulopenem had lower ED50, in other words stronger antimicrobial activities than IPM. The therapeutic effect of sulopenem are related well with its MIC value. In guinea pigs experimental lung infection with Klebsiella pneumoniae, sulopenem was more effective than CZON or cefotiam.

Antibacterial and antifungal activity of Flindersine isolated from the traditional medicinal plant, Toddalia asiatica (L.) Lam.

PubMed

Duraipandiyan, V; Ignacimuthu, S

2009-06-25

The leaves and root of Toddalia asiatica (L.) Lam. (Rutaceae) are widely used as a folk medicine in India. Hexane, chloroform, ethyl acetate, methanol and water extracts of Toddalia asiatica leaves and isolated compound Flindersine were tested against bacteria and fungi. Antibacterial and antifungal activities were tested against bacteria and fungi using disc-diffusion method and minimum inhibitory concentrations (MICs). The compound was confirmed using X-ray crystallography technique. Antibacterial and antifungal activities were observed in ethyl acetate extract. One active principle Flindersine (2,6-dihydro-2,2-dimethyl-5H-pyrano [3,2-c] quinoline-5-one-9cl) was isolated from the ethyl acetate extract. The MIC values of the compound against bacteria Bacillus subtilis (31.25 microg/ml), Staphylococcus aureus (62.5 microg/ml), Staphylococcus epidermidis (62.5 microg/ml), Enterococcus faecalis (31.25 microg/ml), Pseudomonas aeruginosa (250 microg/ml), Acinetobacter baumannii (125 microg/ml) and fungi Trichophyton rubrum 57 (62.5 microg/ml), Trichophyton mentagrophytes (62.5 microg/ml), Trichophyton simii (62.5 microg/ml), Epidermophyton floccosum (62.5 microg/ml), Magnaporthe grisea (250 microg/ml) and Candida albicans (250 microg/ml) were determined. Ethyl acetate extract showed promising antibacterial and antifungal activity and isolated compound Flindersine showed moderate activity against bacteria and fungi.

Effect of Liquid Crystalline Systems Containing Antimicrobial Compounds on Infectious Skin Bacteria.

PubMed

Souza, Carla; Watanabe, Evandro; Aires, Carolina Patrícia; Lara, Marilisa Guimarães

2017-08-01

This study aimed (i) to prepare liquid crystalline systems (LCS) of glyceryl monooleate (GMO) and water containing antibacterial compounds and (ii) to evaluate their potential as drug delivery systems for topical treatment of bacterial infections. Therefore, LCS containing CPC (cetylpyridinium chloride) (LCS/CPC) and PHMB (poly(hexamethylene biguanide) hydrochloride) (LCS/PHMB) were prepared and the liquid crystalline phases were identified by polarizing light microscopy 24 h and 7 days after preparation. The in vitro drug release profile and in vitro antibacterial activity of the systems were assessed using the double layer agar diffusion method against Staphylococcus aureus, methicillin-resistant S. aureus, Staphylococcus epidermidis, Escherichia coli, and Enterococcus faecalis. The interaction between GMO and the drugs was evaluated by a drug absorption study. Stable liquid crystalline systems containing CPC and PHMB were obtained. LCS/PHMB decreased the PHMB release rate and exerted strong antibacterial activity against all the investigated bacteria. In contrast, CPC interacted with GMO so strongly that it became attached to the system; the amount released was not sufficient to exert antibacterial activity. Therefore, the studied liquid crystalline systems were suitable to deliver PHMB, but not CPC. Accordingly, it was demonstrated that GMO interacts with each drug differently, which may interfere in the final efficiency of GMO/water LCS.

Genomics of Staphylococcus

NASA Astrophysics Data System (ADS)

Lindsay, Jodi A.

The staphylococci are Gram-positive cocci that divide to form clusters that look like grapes. By 16S ribosomal sequencing, they are most closely related to the Gram-positive, low G+C content Bacillus-Lactobacillus-Staphylococcus genera (Woese, 1987). There are over 30 species of staphylococci identified, and they are typically found on the skin and mucous membranes of mammals. About a dozen species are frequently carried on humans, including Staphylococcus aureus, Staphylococcus epidermidis, Staphylococcus haemolyticus, Staphylococcus capitis, Staphylococcus hominis, Staphylococcus cohnii, Staphylococcus lugdunensis, Staphylococcus schleiferi, Staphylococcus saprophyticus, Staphylococcus simulans, Staphylococcus warneri and Staphylococcus xylosus.

Loofah sponges as reservoirs and vehicles in the transmission of potentially pathogenic bacterial species to human skin.

PubMed Central

Bottone, E J; Perez, A A; Oeser, J L

1994-01-01

Loofah sponges are natural products used as exfoliative beauty aids. As a consequence of tracing a case of Pseudomonas aeruginosa folliculitis to a contaminated loofah sponge, we assessed the role of loofah sponges in supporting the growth of a wide variety of bacterial species. Our data show growth enhancement of sterile loofah fragments for numerous gram-negative (Pseudomonas, Xanthomonas, and Klebsiella) and gram-positive (Enterococcus and group B Streptococcus) species of human and environmental origin. Furthermore, hydrated new, unused loofah sponges undergo a shift in bacterial flora from sparse colonies of Bacillus spp. and Staphylococcus epidermidis to a predominantly gram-negative flora. The growth-promoting potential of loofah sponges (and other exfoliatives) can be further augmented by desquamated epithelial cells entrapped in the loofah fibrous matrix. Therefore, as loofah sponges (and other exfoliatives) can serve as a reservoir and a vehicle for the transmission of potentially pathogenic species to the human skin, we recommend their decontamination with hypochlorite (10%) bleach at regular intervals. Images PMID:8150959

Loofah sponges as reservoirs and vehicles in the transmission of potentially pathogenic bacterial species to human skin.

PubMed

Bottone, E J; Perez, A A; Oeser, J L

1994-02-01

Loofah sponges are natural products used as exfoliative beauty aids. As a consequence of tracing a case of Pseudomonas aeruginosa folliculitis to a contaminated loofah sponge, we assessed the role of loofah sponges in supporting the growth of a wide variety of bacterial species. Our data show growth enhancement of sterile loofah fragments for numerous gram-negative (Pseudomonas, Xanthomonas, and Klebsiella) and gram-positive (Enterococcus and group B Streptococcus) species of human and environmental origin. Furthermore, hydrated new, unused loofah sponges undergo a shift in bacterial flora from sparse colonies of Bacillus spp. and Staphylococcus epidermidis to a predominantly gram-negative flora. The growth-promoting potential of loofah sponges (and other exfoliatives) can be further augmented by desquamated epithelial cells entrapped in the loofah fibrous matrix. Therefore, as loofah sponges (and other exfoliatives) can serve as a reservoir and a vehicle for the transmission of potentially pathogenic species to the human skin, we recommend their decontamination with hypochlorite (10%) bleach at regular intervals.

Capillary isoelectric focusing and fluorometric detection of proteins and microorganisms dynamically modified by poly(ethylene glycol) pyrenebutanoate.

PubMed

Horka, Marie; Ruzicka, Filip; Horký, Jaroslav; Holá, Veronika; Slais, Karel

2006-12-15

The nonionogenic pyrene-based tenside, poly(ethylene glycol) pyrenebutanoate, was prepared and applied in capillary isoelectric focusing with fluorometric detection. This dye was used here as a buffer additive in capillary isoelectric focusing for a dynamic modification of the sample of proteins and microorganisms. The values of the isoelectric points of the labeled bioanalytes were calculated with use of the fluorescent pI markers and were found comparable with pI of the native compounds. The mixed cultures of proteins and microorganisms, Escherichia coli CCM 3954, Staphylococcus epidermidis CCM 4418, Proteus vulgaris, Enterococcus faecalis CCM 4224, and Stenotrophomonas maltophilia, the strains of the yeast cells, Candida albicans CCM 8180, Candida krusei, Candida parapsilosis, Candida glabrata, Candida tropicalis, and Saccharomyces cerevisiae were reproducibly focused and separated by the suggested technique. Using UV excitation for the on-column fluorometric detection, the minimum detectable amount was down to 10 cells injected on the separation capillary.

Extracellular DNA impedes the transport of vancomycin in Staphylococcus epidermidis biofilms preexposed to subinhibitory concentrations of vancomycin.

PubMed

Doroshenko, Natalya; Tseng, Boo Shan; Howlin, Robert P; Deacon, Jill; Wharton, Julian A; Thurner, Philipp J; Gilmore, Brendan F; Parsek, Matthew R; Stoodley, Paul

2014-12-01

Staphylococcus epidermidis biofilm formation is responsible for the persistence of orthopedic implant infections. Previous studies have shown that exposure of S. epidermidis biofilms to sub-MICs of antibiotics induced an increased level of biofilm persistence. BODIPY FL-vancomycin (a fluorescent vancomycin conjugate) and confocal microscopy were used to show that the penetration of vancomycin through sub-MIC-vancomycin-treated S. epidermidis biofilms was impeded compared to that of control, untreated biofilms. Further experiments showed an increase in the extracellular DNA (eDNA) concentration in biofilms preexposed to sub-MIC vancomycin, suggesting a potential role for eDNA in the hindrance of vancomycin activity. Exogenously added, S. epidermidis DNA increased the planktonic vancomycin MIC and protected biofilm cells from lethal vancomycin concentrations. Finally, isothermal titration calorimetry (ITC) revealed that the binding constant of DNA and vancomycin was 100-fold higher than the previously reported binding constant of vancomycin and its intended cellular d-Ala-d-Ala peptide target. This study provides an explanation of the eDNA-based mechanism of antibiotic tolerance in sub-MIC-vancomycin-treated S. epidermidis biofilms, which might be an important factor for the persistence of biofilm infections. Copyright © 2014, American Society for Microbiology. All Rights Reserved.

Effects of Total Alkaloids of Sophora alopecuroides on Biofilm Formation in Staphylococcus epidermidis

PubMed Central

Li, Xue; Guan, Cuiping; He, Yulong; Wang, Yujiong

2016-01-01

Staphylococcus epidermidis (S. epidermidis) is an opportunistic pathogen with low pathogenicity and a cause of the repeated outbreak of bovine mastitis in veterinary clinical settings. In this report, a biofilm model of S. epidermidis was generated and the minimal inhibitory concentration (MIC) and sub-MIC (SMIC) on bacterial cultures were assessed for the following agents: total alkaloids of Sophora alopecuroides (TASA), ciprofloxacin (CIP), and erythromycin (ERY). The formation and characteristic parameters of biofilm were analyzed in terms of XTT assay, silver staining, and confocal laser scanning microscope (CLSM). Results showed that a sub-MIC of TASA could inhibit 50% biofilm of bacterial activity, while 250-fold MIC of CIP and ERY MICs only inhibited 50% and 47% of biofilm formation, respectively. All three agents could inhibit the biofilm formation at an early stage, but TASA showed a better inhibitory effect on the late stage of biofilm thickening. A morphological analysis using CLSM further confirmed the destruction of biofilm by these agents. These results thus suggest that TASA has an inhibitory effect on biofilm formation of clinic S. epidermidis, which may be a potential agent warranted for further study on the treatment prevention of infection related to S. epidermidis in veterinary clinic. PMID:27413745

Possible Correlation Between Bile Salt Hydrolysis and AHL Deamidation: Staphylococcus epidermidis RM1, a Potent Quorum Quencher and Bile Salt Hydrolase Producer.

PubMed

Mukherji, Ruchira; Prabhune, Asmita

2015-05-01

The aim of the present work was to isolate a bile salt hydrolase (BSH) producer from fermented soy curd and explore the ability of the BSH produced to cleave bacterial quorum sensing signals. Bacterial isolates with possible ability to deconjugate bile salts were enriched and isolated on De Man, Rogosa and Sharpe (MRS) medium containing 0.2% bile salts. BSH-producing positive isolate with orange-pink-pigmented colonies was isolated and was identified as a strain of Staphylococcus epidermidis using biochemical and phylogenetic tools. S. epidermidis RM1 was shown to possess both potent BSH and N-acyl homoserine lactone (AHL) cleavage activity. Genetic basis of this dual-enzyme activity was explored by means of specific primers designed using S. epidermidis ATCC 12228 genome as template. It was observed that a single enzyme was not responsible for both the activity. Two different genetic elements corresponding to each of the enzymatic activity were successfully amplified from the genomic DNA of the isolate.

SdrF, a Staphylococcus epidermidis Surface Protein, Contributes to the Initiation of Ventricular Assist Device Driveline–Related Infections

PubMed Central

Arrecubieta, Carlos; Toba, Faustino A.; von Bayern, Manuel; Akashi, Hirokazu; Deng, Mario C.; Naka, Yoshifumi; Lowy, Franklin D.

2009-01-01

Staphylococcus epidermidis remains the predominant pathogen in prosthetic-device infections. Ventricular assist devices, a recently developed form of therapy for end-stage congestive heart failure, have had considerable success. However, infections, most often caused by Staphylococcus epidermidis, have limited their long-term use. The transcutaneous driveline entry site acts as a potential portal of entry for bacteria, allowing development of either localized or systemic infections. A novel in vitro binding assay using explanted drivelines obtained from patients undergoing transplantation and a heterologous lactococcal system of surface protein expression were used to identify S. epidermidis surface components involved in the pathogenesis of driveline infections. Of the four components tested, SdrF, SdrG, PIA, and GehD, SdrF was identified as the primary ligand. SdrF adherence was mediated via its B domain attaching to host collagen deposited on the surface of the driveline. Antibodies directed against SdrF reduced adherence of S. epidermidis to the drivelines. SdrF was also found to adhere with high affinity to Dacron, the hydrophobic polymeric outer surface of drivelines. Solid phase binding assays showed that SdrF was also able to adhere to other hydrophobic artificial materials such as polystyrene. A murine model of infection was developed and used to test the role of SdrF during in vivo driveline infection. SdrF alone was able to mediate bacterial adherence to implanted drivelines. Anti-SdrF antibodies reduced S. epidermidis colonization of implanted drivelines. SdrF appears to play a key role in the initiation of ventricular assist device driveline infections caused by S. epidermidis. This pluripotential adherence capacity provides a potential pathway to infection with SdrF-positive commensal staphylococci first adhering to the external Dacron-coated driveline at the transcutaneous entry site, then spreading along the collagen-coated internal portion of the driveline to establish a localized infection. This capacity may also have relevance for other prosthetic device–related infections. PMID:19412528

Staphylococcus epidermidis induces complement activation, tumor necrosis factor and interleukin-1, a shock-like state and tissue injury in rabbits without endotoxemia. Comparison to Escherichia coli.

PubMed Central

Wakabayashi, G; Gelfand, J A; Jung, W K; Connolly, R J; Burke, J F; Dinarello, C A

1991-01-01

Tumor necrosis factor (TNF) and IL-1 are thought to mediate many of the pathophysiologic changes of endotoxemia and Gram-negative bacteremia. In these studies, heat-killed Staphylococcus epidermidis were infused into rabbits to determine whether an endotoxin (LPS)-free microorganism also elicits cytokinemia and the physiologic abnormalities seen in Gram-negative bacteremia. S. epidermidis induced complement activation, circulating TNF and IL-1, and hypotension to the same degree as did one-twentieth the number of heat-killed Escherichia coli. Circulating IL-1 beta levels had a greater correlation coefficient (r = 0.81, P less than 0.001) with the degree of hypotension than TNF levels (r = 0.48, P less than 0.02). Leukopenia, thrombocytopenia, diffuse pulmonary capillary aggregation of neutrophils, and hepatic necrosis with neutrophil infiltration were observed to the same extent after either S. epidermidis or E. coli infusion. However, S. epidermidis infusion did not induce significant (less than 60 pg/ml) endotoxemia, whereas E. coli infusion resulted in high (11,000 pg/ml) serum endotoxin levels. S. epidermidis, E. coli, LPS, or S. epidermidis-derived lipoteichoic acid (LTA) induced TNF and IL-1 from blood mononuclear cells in vitro. E. coli organisms and LPS were at least 100-fold more potent than S. epidermidis or LTA. Thus, a shock-like state with similar levels of complement activation as well as circulating levels of IL-1 and TNF were observed following either S. epidermidis or E. coli. These data provide further evidence that host factors such as IL-1 and TNF are common mediators of the septic shock syndrome regardless of the organism. Images PMID:2040686

Antimicrobial resistance and population structure of Staphylococcus epidermidis recovered from animals and humans.

PubMed

Argudín, M Angeles; Vanderhaeghen, Wannes; Vandendriessche, Stien; Vandecandelaere, Ilse; André, François-Xavier; Denis, Olivier; Coenye, Tom; Butaye, Patrick

2015-07-09

While Staphylococcus epidermidis, as part of the commensal flora, is a well-known human opportunistic pathogen, only little is known about the genetic relatedness of S. epidermidis carriage isolates from animal and human origin. This study aimed to compare S. epidermidis recovered from livestock, livestock-farmers and humans associated with the hospital environment. A total of 193 S. epidermidis isolates from three populations [animals (n=33), farmers (n=86) and hospital-associated (n=74)] were characterized by broth microdilution antimicrobial susceptibility testing, staphylococcal cassette chromosome mec (SCCmec) typing, pulsed field gel electrophoresis (PFGE) and multilocus sequence typing (MLST). The overall S. epidermidis nasal colonization rate was low in animals (1-9%) but high among farmers (75%). High levels of multi-resistance were found in all populations. Tetracycline resistance was high in animal and farmer isolates; resistance to erythromycin, clindamycin and trimethoprim was high in animal and hospital-associated isolates. Methicillin-resistant S. epidermidis - MRSE isolates were found in all collections, with 22 (67%) MRSE in animals, 44 (51%) MRSE in farmers and 42 (57%) MRSE associated with the hospital-setting. Known SCCmec types and variants were detected in 79% of MRSE; the rest were non-typeable cassettes. In total 79 PFGE-types were found, of which 22 were shared between livestock, farmers and the hospital settings. Clonal complex 2 was predominant in all three populations and most STs corresponded to types previously observed in community and nosocomial S. epidermidis populations. S. epidermidis isolates from livestock, farmers and hospital-setting showed a high level of diversity, but some clones can be found in humans as well as in animals. Copyright © 2015 Elsevier B.V. All rights reserved.

Comparative characterisation of the biofilm-production abilities of Staphylococcus epidermidis isolated from human skin and platelet concentrates.

PubMed

Taha, Mariam; Kohnen, Carissa; Mallya, Shruti; Kou, Yuntong; Zapata, Adriana; Ramirez-Arcos, Sandra

2018-02-01

Staphylococcus epidermidis is the predominant contaminant of platelet concentrates (PCs), a blood product used to treat patients with platelet deficiencies. This microorganism is able to form surface-attached aggregates (biofilms) in human skin. Herein, the abundance of S. epidermidis biofilm-producers in contaminated PCs compared to skin isolates was explored. Furthermore, the potential positive selection of S. epidermidis biofilm-producers during the blood donation process and PC manufacturing was investigated. Twenty-four S. epidermidis isolates obtained from contaminated PCs and 48 S. epidermidis isolates obtained from the venipuncture area of human volunteers were compared for their ability to form biofilms in laboratory media and in PCs using a semi quantitative crystal violet assay. Also, the presence of the biofilm-associated icaA and icaD genes was assessed by PCR-amplification.Results/Key findings.Biofilm production in laboratory media showed a higher number of S. epidermidis biofilm-producers in the skin-derived group (43.7 %) compared to the PC-derived isolates (25 %). However, all skin and PC isolates formed biofilms in PCs. The prevalence of ica-positive biofilm-producer isolates was similar in PC and skin isolates (16.6 and 18.8 %, respectively). In contrast, the abundance of ica-negative biofilm-producers was lower in PC isolates compared to skin isolates (8.3 vs 25 %, respectively). Positive selection of S. epidermidis biofilm-producers during blood donation and PC manufacturing was not observed. Interestingly, ica-negative biofilm-producers seem to be negatively affected by skin disinfection, blood processing and PC storage. Furthermore, this study shows that S. epidermidis adopts a biofilm-forming phenotype in PCs regardless of its genetic background or origin.

The in vitro effect of xylitol on chronic rhinosinusitis biofilms.

PubMed

Jain, R; Lee, T; Hardcastle, T; Biswas, K; Radcliff, F; Douglas, R

2016-12-01

Biofilms have been implicated in chronic rhinosinusitis (CRS) and may explain the limited efficacy of antibiotics. There is a need to find more effective, non-antibiotic based therapies for CRS. This study examines the effects of xylitol on CRS biofilms and planktonic bacteria. Crystal violet assay and spectrophotometry were used to quantify the effects of xylitol (5% and 10% solutions) against Staphylococcus epidermidis, Pseudomonas aeruginosa, and Staphylococcus aureus. The disruption of established biofilms, inhibition of biofilm formation and effects on planktonic bacteria growth were investigated and compared to saline and no treatment. Xylitol 5% and 10% significantly reduced biofilm biomass (S. epidermidis), inhibited biofilm formation (S. aureus and P. aeruginosa) and reduced growth of planktonic bacteria (S. epidermidis, S. aureus, and P. aeruginosa). Xylitol 5% inhibited formation of S. epidermidis biofilms more effectively than xylitol 10%. Xylitol 10% reduced S. epidermidis planktonic bacteria more effectively than xylitol 5%. Saline, xylitol 5% and 10% disrupted established biofilms of S. aureus when compared with no treatment. No solution was effective against established P. aeruginosa biofilm. Xylitol has variable activity against biofilms and planktonic bacteria in vitro and may have therapeutic efficacy in the management of CRS.

Antimicrobial efficacy of chlorhexidine digluconate alone and in combination with eucalyptus oil, tea tree oil and thymol against planktonic and biofilm cultures of Staphylococcus epidermidis.

PubMed

Karpanen, T J; Worthington, T; Hendry, E R; Conway, B R; Lambert, P A

2008-11-01

Effective skin antisepsis and disinfection of medical devices are key factors in preventing many healthcare-acquired infections associated with skin microorganisms, particularly Staphylococcus epidermidis. The aim of this study was to investigate the antimicrobial efficacy of chlorhexidine digluconate (CHG), a widely used antiseptic in clinical practice, alone and in combination with tea tree oil (TTO), eucalyptus oil (EO) and thymol against planktonic and biofilm cultures of S. epidermidis. Antimicrobial susceptibility assays against S. epidermidis in a suspension and in a biofilm mode of growth were performed with broth microdilution and ATP bioluminescence methods, respectively. Synergy of antimicrobial agents was evaluated with the chequerboard method. CHG exhibited antimicrobial activity against S. epidermidis in both suspension and biofilm (MIC 2-8 mg/L). Of the essential oils thymol exhibited the greatest antimicrobial efficacy (0.5-4 g/L) against S. epidermidis in suspension and biofilm followed by TTO (2-16 g/L) and EO (4-64 g/L). MICs of CHG and EO were reduced against S. epidermidis biofilm when in combination (MIC of 8 reduced to 0.25-1 mg/L and MIC of 32-64 reduced to 4 g/L for CHG and EO, respectively). Furthermore, the combination of EO with CHG demonstrated synergistic activity against S. epidermidis biofilm with a fractional inhibitory concentration index of <0.5. The results from this study suggest that there may be a role for essential oils, in particular EO, for improved skin antisepsis when combined with CHG.

[The influence of a new surface treatment of silicone intracoular lenses with fluoralkylsitan on the adherence of endophthalmitic bacteria in vitro

PubMed

Kienast, A; Menz, D-H; Dresp, J; Klinger, M; Bunse, A; Ohgke, H; Solbach, W; Laqua, H; Kämmerer, R; Hoerauf, H

2003-10-01

Dynasilan is a fluoroalkylsilan which is able to bind to surface active molecules of intraocular lenses (IOLs), thereby offering a new option for surface modification of silicone lenses. The purpose of this in vitro study was to investigate the influence of this new surface treatment on the adherence of two typical endophthalmitis-inducing bacteria ( Staphylococcus epidermidis, Propionibacterium acnes). A total of 14 Dynasilan-treated and 14 untreated silicone lenses were incubated at 37 degrees C for 24 h in brain heart infusion broth (10(8) CFU/ml) either with Staphylococcus epidermidis or with Propionibacterium acnes for 1 h. Subsequently, the adherent bacteria were resuspended using ultrasonification at 35 kHz for 3 x 45 s. After a dilution series and incubation at 37 degrees C for 24 h or 3 days the colonies were counted. On untreated IOLs incubated with Staphylococcus epidermidis the average number of bacteria was 3.6 x 10(7)/ml, and on treated IOLs the number of counted colonies was reduced to 1.09 x 10(7)/ml. Incubated with Propionibacterium acnes the average number of adherent bacteria on untreated IOLs was 4.75 x 10(4)/ml and on modified IOLs the number was reduced to 2.94 x 10(4)/ml. Dynasilan surface treatment may reduce the adherence of Staphylococcus epidermidis and Propionibacterium acnes on silicone intraocular lenses. Further studies regarding the stability of this treatment, its biocompatibility and influence on lens epithelial cell adhesion are in progress.

Synergistic Photothermal and Antibiotic Killing of Biofilm-Associated Staphylococcus aureus Using Targeted Antibiotic-Loaded Gold Nanoconstructs.

PubMed

Meeker, Daniel G; Jenkins, Samir V; Miller, Emily K; Beenken, Karen E; Loughran, Allister J; Powless, Amy; Muldoon, Timothy J; Galanzha, Ekaterina I; Zharov, Vladimir P; Smeltzer, Mark S; Chen, Jingyi

2016-04-08

Resistance to conventional antibiotics is a growing public health concern that is quickly outpacing the development of new antibiotics. This has led the Infectious Diseases Society of America (IDSA) to designate Enterococcus faecium , Staphylococcus aureus , Klebsiella pneumoniae , Acinetobacter baumannii , Pseudomonas aeruginosa , and Enterobacter species as "ESKAPE pathogens" on the basis of the rapidly decreasing availability of useful antibiotics. This emphasizes the urgent need for alternative therapeutic strategies to combat infections caused by these and other bacterial pathogens. In this study, we used Staphylococcus aureus ( S. aureus ) as a proof-of-principle ESKAPE pathogen to demonstrate that an appropriate antibiotic (daptomycin) can be incorporated into polydopamine-coated gold nanocages (AuNC@PDA) and that daptomycin-loaded AuNC@PDA can be conjugated to antibodies targeting a species-specific surface protein (staphylococcal protein A; Spa) as a means of achieving selective delivery of the nanoconstructs directly to the bacterial cell surface. Targeting specificity was confirmed by demonstrating a lack of binding to mammalian cells, reduced photothermal and antibiotic killing of the Spa-negative species Staphylococcus epidermidis , and reduced killing of S. aureus in the presence of unconjugated anti-Spa antibodies. We demonstrate that laser irradiation at levels within the current safety standard for use in humans can be used to achieve both a lethal photothermal effect and controlled release of the antibiotic, thus resulting in a degree of therapeutic synergy capable of eradicating viable S. aureus cells. The system was validated using planktonic bacterial cultures of both methicillin-sensitive and methicillin-resistant S. aureus strains and subsequently shown to be effective in the context of an established biofilm, thus indicating that this approach could be used to facilitate the effective treatment of intrinsically resistant biofilm infections.

Low-intensity LED (625 and 405 nm) and laser (805 nm) killing of Propionibacterium acnes and Staphylococcus epidermidis

NASA Astrophysics Data System (ADS)

Tuchina, Elena S.; Tuchin, Valery V.

2009-02-01

In the present work we have investigated in vitro sensitivity of microorganisms P. acnes and S. epidermidis to action of red (625 nm and 405 nm) and infrared (805 nm) radiations in combination with photosensitizes Methylene Blue and Indocyanine Green.

Virulence factors of biotypes of Staphylococcus epidermidis from clinical sources.

PubMed Central

Males, B M; Rogers, W A; Parisi, J T

1975-01-01

The biotyping scheme of Baird-Parker was applied to cultures of Staphylococcus epidermidis from patients. In all, 63.6% of 228 cultures belonged to biotype 1, followed by biotypes 4, 3, and 2 in decreasing order of incidence. When classified according to clinical source of isolation, cultures of S. epidermidis were most frequently isolated from urine, with 39.5% of 228 cultures from this source. Each of the four biotypes was distributed throughout all nine catagories of clinical sources. The production of virulence factors was based on the results of three groups of tests: (i) deoxyribonuclease, urease, gelatinase, caseinase, and lysozyme production; (ii) lipolytic activity on the tweens; and (iii) hemolysin production. Enzymatic activity was highest for organisms in biotypes 1, followed by biotypes 3, 4, and 2 in decreasing order. Of the 228 cultures, 76.3% were lysed by lysostaphin. Resistance to antibiotics was highest for tetracycline, ampicillin, and penicillin, with rates of 54.8, 69.3, and 81.6%, respectively. The role of S. epidermidis as an etiological agent was studied by analyzing the laboratory and clinical data of 80 patients selected at random with bacteriuric S. epidermidis. Organisms in biotype 1 were most commonly associated with urinary tract infection. The significance of certain biotypes of S. epidermidis as opportunistic pathogens among compromised hosts in a hospital environment is discussed. PMID:1176603

High proportions of Staphylococcus epidermidis in dental caries harbor multiple classes of antibiotics resistance, significantly increase inflammatory interleukins in dental pulps.

PubMed

Devang Divakar, Darshan; Muzaheed; Aldeyab, Sultan Salem; Alfawaz, Sara A; AlKheraif, Abdulaziz Abdullah; Ahmed Khan, Aftab

2017-08-01

Staphylococcus epidermidis is one of most prevalent in dental caries or dental pulp which has the capability of horizontal genetic transfer between different bacterial species in the oropharynx, suggesting that it may evolve with the dissemination of resistant determinants, This study was performed to molecularly characterize and differentiate S. epidermidis isolated from dental caries and healthy individual. Also, two important cytokines in inflammation were assayed caused due to S. epidermidis of health and dental caries sources. Dental caries strains were more resistant with high MIC 50 and MIC 90 value. These isolates also showed the presence of mecA gene and another virulence gene i. e sea and seb comparatively more than healthy individual isolates. SCCmec types, III and IV was more prevalent in dental caries isolates where an as healthy individual was more non-typable. Additionally, the quantity of IL-1β and IL-8 caused due to dental caries isolates was seen more which indicate dental caries isolates are able to induce. This study showed that S. epidermidis a normal flora of oropharyngeal are more diverse to those strains which cause dental caries. S. epidermidis owns a prodigious genetic plasticity that permits to obtain, lose or regulate genetic elements that provide compensations to improve its colonization in the host. Copyright © 2017 Elsevier Ltd. All rights reserved.

[The use of teicoplanin in neutropenic patients: values and limits].

PubMed

Espinouse, D; Chomarat, M

1990-06-01

The efficacy and the safety of teicoplanin were evaluated for the treatment of febrile episodes in neutropenic patients. A total of 18 patients received teicoplanin once daily as an intravenous injection of 200 mg in 6 patients (after a loading dose of 400 mg) or 400 mg in 12 patients (loading dose: 800 mg). The mean duration of therapy was 15.9 days (range 9 to 39 days). In all patients teicoplanin was combined with another antibiotic usually a beta-lactam. Thirteen of 18 patients were successfully treated. Three febrile episodes proved to be microbiologically documented infections and were cured by teicoplanin: one Streptococcus mitis and two methicillin-resistant (methi-R) Staphylococcus epidermidis bacteremias. Neither toxicity nor side effects were observed in the reported group. Six patients experiencing reactions to vancomycin (2 cases of cutaneous allergy) or to vancomycin and amphotericin B combination (4 cases of nephrotoxicity) were subsequently treated with teicoplanin without any evidence of cross-sensitivity. We observed emergence of teicoplanin-resistant coagulase-negative Staphylococcus in 3 patients receiving teicoplanin: 20, 18 and 8 days after a first febrile episode cured by teicoplanin and a beta-lactam, they developed fever while receiving the same antibiotic regimen. Methi-R Staphylococcus epidermidis was isolated from blood cultures in the first patient and methi-R Staphylococcus haemolyticus in the two other patients. In one patient, successfully treated by teicoplanin for a first febrile episode related to a methi-R Staphylococcus epidermidis, emergence of Staphylococcus haemolyticus occurred 8 days later while the patient was on teicoplanin therapy (6 mg/kg). MICs of teicoplanin were 16 mg/l for the two Staphylococcus strains isolated in this patient.(ABSTRACT TRUNCATED AT 250 WORDS)

Activity of ciprofloxacin against multiply resistant strains of Pseudomonas aeruginosa, Staphylococcus epidermidis, and group JK corynebacteria.

PubMed Central

Venezio, F R; Tatarowicz, W; DiVincenzo, C A; O'Keefe, J P

1986-01-01

The susceptibilities of multiply resistant clinical isolates of Pseudomonas aeurginosa to ciprofloxacin, norfloxacin, and several beta-lactam and aminoglycoside antibiotics were evaluated. Ciprofloxacin also was compared with methicillin and vancomycin against methicillin-resistant Staphylococcus epidermidis and group JK corynebacteria. Ciprofloxacin exhibited the lowest MICs and MBCs for 90% of the isolates among all of the antibiotics tested against P. aeruginosa. In addition, ciprofloxacin exhibited excellent bactericidal activity against the gram-positive organisms. Clinical trials are necessary to confirm the in vitro results and monitor for emergence of resistance. PMID:3101589

The role of the PI3K/mTOR signaling pathway in Staphylococcus epidermidis small colony variants intracellular survival.

PubMed

Magryś, Agnieszka; Bogut, Agnieszka; Kiełbus, Michał; Olender, Alina

2018-04-01

The objective of this study was to analyze how Staphylococcus epidermidis SCV and WT strains manipulate the PI3K/Akt/mTOR signaling pathway. Six S. epidermidis strains with normal phenotype (WT) and six S. epidermidis strains with SCV phenotype were isolated in parallel from six patients with the prosthetic hip joint infections. THP-1 activated cells were incubated with or without PI3K inhibitor-wortmannin or with mTOR inhibitor-rapamycin. Next, macrophages were exposed to S. epidermidis WT and SCV strains. After 4 h incubation, bacterial survival inside macrophages as well as PI3K-mTOR activation was analyzed. SCV strains of S. epidermidis increased the level of Akt phosphorylation, compared to uninfected macrophages and to their parental WT forms. Wild type variants of S. epidermidis phosphorylated Akt at similar or lower levels as control uninfected cells. Next, the induction of mTOR target, phosphorylated ribosomal protein S6, was measured in bacteria-infected macrophages. The level of phosphorylation was significantly reduced when the cells were exposed to WT strains of S. epidermidis. In contrast, the SCV strains activated S6 protein mostly at a level comparable to the control cells. Rapamycin inhibited mTOR activation as the number of p-S6 positive cells decreased in the tested cases. To conclude, the SCV strains activate the PI3K-Akt signaling pathway in opposite to WT strains. This fact however did not influence the increase in the number of live SCV bacteria as compared to the WT strains. Knowing that the PI3K-Akt pathway is involved in proinflammatory cytokines suppression, SCVs seem to use this pathway to reduce the inflammatory response during the infection.

Structure-based discovery of inhibitors of the YycG histidine kinase: New chemical leads to combat Staphylococcus epidermidis infections

PubMed Central

Qin, Zhiqiang; Zhang, Jian; Xu, Bin; Chen, Lili; Wu, Yang; Yang, Xiaomei; Shen, Xu; Molin, Soeren; Danchin, Antoine; Jiang, Hualiang; Qu, Di

2006-01-01

Background Coagulase-negative Staphylococcus epidermidis has become a major frequent cause of infections in relation to the use of implanted medical devices. The pathogenicity of S. epidermidis has been attributed to its capacity to form biofilms on surfaces of medical devices, which greatly increases its resistance to many conventional antibiotics and often results in chronic infection. It has an urgent need to design novel antibiotics against staphylococci infections, especially those can kill cells embedded in biofilm. Results In this report, a series of novel inhibitors of the histidine kinase (HK) YycG protein of S. epidermidis were discovered first using structure-based virtual screening (SBVS) from a small molecular lead-compound library, followed by experimental validation. Of the 76 candidates derived by SBVS targeting of the homolog model of the YycG HATPase_c domain of S. epidermidis, seven compounds displayed significant activity in inhibiting S. epidermidis growth. Furthermore, five of them displayed bactericidal effects on both planktonic and biofilm cells of S. epidermidis. Except for one, the compounds were found to bind to the YycG protein and to inhibit its auto-phosphorylation in vitro, indicating that they are potential inhibitors of the YycG/YycF two-component system (TCS), which is essential in S. epidermidis. Importantly, all these compounds did not affect the stability of mammalian cells nor hemolytic activities at the concentrations used in our study. Conclusion These novel inhibitors of YycG histidine kinase thus are of potential value as leads for developing new antibiotics against infecting staphylococci. The structure-based virtual screening (SBVS) technology can be widely used in screening potential inhibitors of other bacterial TCSs, since it is more rapid and efficacious than traditional screening technology. PMID:17094812

Human cathelicidin peptide LL37 inhibits both attachment capability and biofilm formation of Staphylococcus epidermidis.

PubMed

Hell, E; Giske, C G; Nelson, A; Römling, U; Marchini, G

2010-02-01

The aim of this work was to investigate the possible effect of human cathelicidin antimicrobial peptide LL37 on biofilm formation of Staphylococcus epidermidis, a major causative agent of indwelling device-related infections. We performed initial attachment assay and biofilm formation solid surface assay in microtitre plates, as well as growth experiment in liquid medium using laboratory strain Staph. epidermidis ATCC35984. We found that already a low concentration of the peptide LL37 (1 mg l(-1)) significantly decreased both the attachment of bacteria to the surface and also the biofilm mass. No growth inhibition was observed even at 16 mg l(-1) concentration of LL37, indicating a direct effect of the peptide on biofilm production. As biofilm protects bacteria during infections in humans and allows their survival in a hostile environment, inhibition of biofilm formation by LL37 may have a key role to prevent bacterial colonization on indwelling devices. Our findings suggest that this host defence factor can be a potential candidate in prevention and treatment strategies of Staph. epidermidis infections in humans.

21 CFR 520.314 - Cefadroxil.

Code of Federal Regulations, 2013 CFR

2013-04-01

... Staphylococcus aureus. For the treatment of genitourinary tract infections (cystitis) due to susceptible strains of Escherichia coli, Proteus mirabilis, and S. aureus. (ii) Cats. For the treatment of skin and soft... strains of Pasteurella multocida, S. aureus, Staphylococcus epidermidis, and Streptococcus spp. (3...

21 CFR 520.314 - Cefadroxil.

Code of Federal Regulations, 2010 CFR

2010-04-01

... Staphylococcus aureus. For the treatment of genitourinary tract infections (cystitis) due to susceptible strains of Escherichia coli, Proteus mirabilis, and S. aureus. (ii) Cats. For the treatment of skin and soft... strains of Pasteurella multocida, S. aureus, Staphylococcus epidermidis, and Streptococcus spp. (3...

21 CFR 520.314 - Cefadroxil.

Code of Federal Regulations, 2014 CFR

2014-04-01

... Staphylococcus aureus. For the treatment of genitourinary tract infections (cystitis) due to susceptible strains of Escherichia coli, Proteus mirabilis, and S. aureus. (ii) Cats. For the treatment of skin and soft... strains of Pasteurella multocida, S. aureus, Staphylococcus epidermidis, and Streptococcus spp. (3...

21 CFR 520.314 - Cefadroxil.

Code of Federal Regulations, 2012 CFR

2012-04-01

... Staphylococcus aureus. For the treatment of genitourinary tract infections (cystitis) due to susceptible strains of Escherichia coli, Proteus mirabilis, and S. aureus. (ii) Cats. For the treatment of skin and soft... strains of Pasteurella multocida, S. aureus, Staphylococcus epidermidis, and Streptococcus spp. (3...

21 CFR 520.314 - Cefadroxil.

Code of Federal Regulations, 2011 CFR

2011-04-01

... Staphylococcus aureus. For the treatment of genitourinary tract infections (cystitis) due to susceptible strains of Escherichia coli, Proteus mirabilis, and S. aureus. (ii) Cats. For the treatment of skin and soft... strains of Pasteurella multocida, S. aureus, Staphylococcus epidermidis, and Streptococcus spp. (3...

Analysis of early mesothelial cell responses to Staphylococcus epidermidis isolated from patients with peritoneal dialysis-associated peritonitis.

PubMed

McGuire, Amanda L; Mulroney, Kieran T; Carson, Christine F; Ram, Ramesh; Morahan, Grant; Chakera, Aron

2017-01-01

The major complication of peritoneal dialysis (PD) is the development of peritonitis, an infection within the abdominal cavity, primarily caused by bacteria. PD peritonitis is associated with significant morbidity, mortality and health care costs. Staphylococcus epidermidis is the most frequently isolated cause of PD-associated peritonitis. Mesothelial cells are integral to the host response to peritonitis, and subsequent clinical outcomes, yet the effects of infection on mesothelial cells are not well characterised. We systematically investigated the early mesothelial cell response to clinical and reference isolates of S. epidermidis using primary mesothelial cells and the mesothelial cell line Met-5A. Using an unbiased whole genome microarray, followed by a targeted panel of genes known to be involved in the human antibacterial response, we identified 38 differentially regulated genes (adj. p-value < 0.05) representing 35 canonical pathways after 1 hour exposure to S. epidermidis. The top 3 canonical pathways were TNFR2 signaling, IL-17A signaling, and TNFR1 signaling (adj. p-values of 0.0012, 0.0012 and 0.0019, respectively). Subsequent qPCR validation confirmed significant differences in gene expression in a number of genes not previously described in mesothelial cell responses to infection, with heterogeneity observed between clinical isolates of S. epidermidis, and between Met-5A and primary mesothelial cells. Heterogeneity between different S. epidermidis isolates suggests that specific virulence factors may play critical roles in influencing outcomes from peritonitis. This study provides new insights into early mesothelial cell responses to infection with S. epidermidis, and confirms the importance of validating findings in primary mesothelial cells.

Comparative Transcriptomics Reveals Discrete Survival Responses of S. aureus and S. epidermidis to Sapienic Acid

PubMed Central

Moran, Josephine C.; Alorabi, Jamal A.; Horsburgh, Malcolm J.

2017-01-01

Staphylococcal colonization of human skin is ubiquitous, with particular species more frequent at different body sites. Whereas Staphylococcus epidermidis can be isolated from the skin of every individual tested, Staphylococcus aureus is isolated from <5% of healthy individuals. The factors that drive staphylococcal speciation and niche selection on skin are incompletely defined. Here we show that S. aureus is inhibited to a greater extent than S. epidermidis by the sebaceous lipid sapienic acid, supporting a role for this skin antimicrobial in selection of skin staphylococci. We used RNA-Seq and comparative transcriptomics to identify the sapienic acid survival responses of S. aureus and S. epidermidis. Consistent with the membrane depolarization mode of action of sapienic acid, both species shared a common transcriptional response to counteract disruption of metabolism and transport. The species differed in their regulation of SaeRS and VraRS regulons. While S. aureus upregulated urease operon transcription, S. epidermidis upregulated arginine deiminase, the oxygen-responsive NreABC nitrogen regulation system and the nitrate and nitrite reduction pathways. The role of S. aureus ACME and chromosomal arginine deiminase pathways in sapienic acid resistance was determined through mutational studies. We speculate that ammonia production could contribute to sapienic acid resistance in staphylococci. PMID:28179897

Inhibition of growth of S. epidermidis by hydrothermally synthesized ZnO nanoplates

NASA Astrophysics Data System (ADS)

Abinaya, C.; Mayandi, J.; Osborne, J.; Frost, M.; Ekstrum, C.; Pearce, J. M.

2017-07-01

The antibacterial effect of zinc oxide (ZnO#1) as prepared and annealed (ZnO#2) at 400 °C, Cu doped ZnO (CuZnO), and Ag doped ZnO (AgZnO) nanoplates on Staphylococcus epidermidis was investigated for the inhibition and inactivation of cell growth. The results shows that pure ZnO and doped ZnO samples exhibited antibacterial activity against Staphylococcus epidermidis (S. epidermidis) as compared to tryptic soy broth (TSB). Also it is observed that S. epidermidis was extremely sensitive to treatment with ZnO nanoplates and it is clear that the effect is not purely depend on Cu/Ag. Phase identification of a crystalline material and unit cell dimensions were studied by x-ray powder diffraction (XRD). The scanning electron microscopy (SEM) provides information on sample’s surface topography and the EDX confirms the presence of Zn, O, Cu and Ag. X-ray photo-electron spectroscopy (XPS) was used to analyze the elemental composition and electronic state of the elements that exist within the samples. These studies confirms the formation of nanoplates and the presence of Zn, O, Ag, Cu with the oxidation states  +2, -2, 0 and  +2 respectively. These results indicates promising antibacterial applications of these ZnO-based nanoparticles synthesized with low-cost hydrothermal methods.

Effect of berberine on Staphylococcus epidermidis biofilm formation.

PubMed

Wang, Xiaoqing; Yao, Xiao; Zhu, Zhen'an; Tang, Tingting; Dai, Kerong; Sadovskaya, Irina; Flahaut, Sigrid; Jabbouri, Said

2009-07-01

Staphylococcus epidermidis is one of the main causes of medical device-related infections owing to its adhesion and biofilm-forming abilities on biomaterial surfaces. Berberine is an isoquinoline-type alkaloid isolated from Coptidis rhizoma (huang lian in Chinese) and other herbs with many activities against various disorders. Although the inhibitory effects of berberine on planktonic bacteria have been investigated in a few studies, the capacity of berberine to inhibit biofilm formation has not been reported to date. In this study, we observed that berberine is bacteriostatic for S. epidermidis and that sub-minimal inhibitory concentrations of berberine blocked the formation of S.epidermidis biofilm. Using viability assays and berberine uptake testing, berberine at a concentration of 15-30mug/mL was shown to inhibit bacterial metabolism. Data from this study also indicated that modest concentrations of berberine (30-45mug/mL) were sufficient to exhibit an antibacterial effect and to inhibit biofilm formation significantly, as shown by the tissue culture plate (TCP) method, confocal laser scanning microscopy and scanning electron microscopy for both S. epidermidis ATCC 35984 and a clinical isolate strain SE243. Although the mechanisms of bacterial killing and inhibition of biofilm formation are not fully understood, data from this investigation indicated a potential application for berberine as an adjuvant therapeutic agent for the prevention of biofilm-related infections.

Antibiotic regimen based on population analysis of residing persister cells eradicates Staphylococcus epidermidis biofilms

PubMed Central

Yang, Shoufeng; Hay, Iain D.; Cameron, David R.; Speir, Mary; Cui, Bintao; Su, Feifei; Peleg, Anton Y.; Lithgow, Trevor; Deighton, Margaret A.; Qu, Yue

2015-01-01

Biofilm formation is a major pathogenicity strategy of Staphylococcus epidermidis causing various medical-device infections. Persister cells have been implicated in treatment failure of such infections. We sought to profile bacterial subpopulations residing in S. epidermidis biofilms, and to establish persister-targeting treatment strategies to eradicate biofilms. Population analysis was performed by challenging single biofilm cells with antibiotics at increasing concentrations ranging from planktonic minimum bactericidal concentrations (MBCs) to biofilm MBCs (MBCbiofilm). Two populations of “persister cells” were observed: bacteria that survived antibiotics at MBCbiofilm for 24/48 hours were referred to as dormant cells; those selected with antibiotics at 8 X MICs for 3 hours (excluding dormant cells) were defined as tolerant-but-killable (TBK) cells. Antibiotic regimens targeting dormant cells were tested in vitro for their efficacies in eradicating persister cells and intact biofilms. This study confirmed that there are at least three subpopulations within a S. epidermidis biofilm: normal cells, dormant cells, and TBK cells. Biofilms comprise more TBK cells and dormant cells than their log-planktonic counterparts. Using antibiotic regimens targeting dormant cells, i.e. effective antibiotics at MBCbiofilm for an extended period, might eradicate S. epidermidis biofilms. Potential uses for this strategy are in antibiotic lock techniques and inhaled aerosolized antibiotics. PMID:26687035

Antibacterial activity of Aquilaria crassna leaf extract against Staphylococcus epidermidis by disruption of cell wall

PubMed Central

2013-01-01

Background Aquilaria crassna Pierre ex Lecomte has been traditionally used in Thailand for treatment of infectious diseases such as diarrhoea and skin diseases for a long time. The main objectives of this study were to examine antibacterial activity of the Aquilaria crassna leaf extract against Staphylococcus epidermidis and its underlying mechanism. The antioxidant activity and acute toxicity were studied as well. Methods Antioxidant activities were examined by FRAP, ABTS and DPPH scavenging methods. Antibacterial activity was conducted using disc diffusion assay and the minimum inhibitory concentration (MIC) was determined by dilution method. The minimum bactericidal concentration (MBC) was reported as the lowest concentration producing no growth of microbes in the subcultures. Morphological changes of the microbe were observed by scanning electron microscopy, while an inhibitory effect on biofilm formation was evaluated by phase contrast microscopic analysis. Bacterial cell wall integrity was assessed by transmission electron microscopy. Acute toxicity was conducted in accordance with the OECD for Testing of Chemicals (2001) guidelines. Results The extract exhibited considerable antioxidant activity. Staphylococcus epidermidis was susceptible to the extract with the MIC and MBC of 6 and 12 mg/ml, respectively. The extract caused swelling and distortion of bacterial cells and inhibited bacterial biofilm formation. Rupture of bacterial cell wall occurred after treated with the extract for 24 h. Acute toxicity test in mice showed no sign of toxicity or death at the doses of 2,000 and 15,000 mg/kg body weight. Conclusion The aqueous extract of Aquilaria crassna leaves possesses an in vitro antibacterial activity against Staphylococcus epidermidis, with no sign of acute oral toxicity in mice, probably by interfering with bacterial cell wall synthesis and inhibiting biofilm formation. PMID:23962360

Antibiotic Susceptibility of Staphylococci Isolates from Patients with Chronic Conjunctivitis: Including Associated Factors and Clinical Evaluation

PubMed Central

Núñez, María Ximena

2013-01-01

Abstract Purpose To determine species of staphylococci in chronic conjunctivitis, their antibiotic susceptibility pattern, patient treatments, clinical course, and clinical conditions. Methods In this prospective study, 243 conjunctival cultures were taken from 191 patients with chronic conjunctivitis, we obtained staphylococci susceptibility patterns with E-test, and they were analyzed in coagulase-positive and negative. The minimum inhibitory concentration for 90% of isolates (MIC90) was determined for Staphylococcus aureus and Staphylococcus epidermidis. Additionally, clinical follow-up and associated factors of all patients were analyzed depending on methicillin resistance (MR) or susceptibility (MS) bacterial state. Results One hundred and eight (44%) cultures were positive; 81 positive cultures were Gram-positive of which, 77 were staphylococci, 29 coagulase-positive with S. aureus as the most prevalent, 89% MS, and 11% MR. And 48 were coagulase-negative with S. epidermidis as the most isolated with 36% of MS and 64% of MR. Poor susceptibility was found in the staphylococcus coagulase-negative/MR group. Moxifloxacin and vancomycin show the best in vitro activity for all isolates. The MIC90 of moxifloxacin and vancomycin were 0.064/1.5, 0.64/3.0, and 1/3.0 for S. aureus-MS, S. epidermidis-MS, and S. epidermidis-MR, respectively. The most frequently associated factors found in patients with positive culture for staphylococcus were exposure to the health care system 23 (29.87%) of 77 patients and dry eye 23 (29.87%) of 77 patients. Both with a proportion of 3 in 10. Conclusion Coagulase-negative staphylococci were the most frequently isolated from the conjunctiva with 58.33% of MR; even though multiresistance was detected, their susceptibility to a fourth-generation fluoroquinolone, commonly used, such as moxifloxacin, was preserved. PMID:23944906

Methods to identify enzymes that degrade the main extracellular polysaccharide component of Staphylococcus epidermidis biofilms

PubMed Central

Gökçen, Anke; Vilcinskas, Andreas; Wiesner, Jochen

2013-01-01

The production of extracellular poly-β-1,6-N-acetyl-d-glucosamine (PNAG) by Staphylococcus epidermidis is the principal determinant of biofilm formation on indwelling medical devices. Enzymes that degrade PNAG therefore provide an attractive strategy for biofilm removal and for the manufacture of biofilm-resistant coatings. Here we present methods that allow the identification of PNAG-degrading enzymes with the ability to detach biofilms. Our protocol includes the preparation of soluble PNAG from S. epidermidis cultures, the incubation of soluble PNAG with candidate enzymes and assays that detect the release of N-acetyl-d-glucosamine using high-pH anion-exchange chromatography (HPAEC) followed in parallel by pulsed amperometric detection (PAD) and online electrospray ionization mass spectrometry (ESI-MS). We validated our procedures using dispersin B, which is currently the only known PNAG-degrading enzyme. PMID:23357872

Photodynamic UVA-riboflavin bacterial elimination in antibiotic-resistant bacteria.

PubMed

Makdoumi, Karim; Bäckman, Anders

2016-09-01

To evaluate the bactericidal effect of clinical ultraviolet A (UVA) settings used in photoactivated chromophore for infectious keratitis (PACK)-collagen cross-linking (CXL) in antibiotic-resistant and non-resistant bacterial strains. Well-characterized bacterial strains from clinical isolates, without and with antibiotic resistance, were studied in a pairwise comparison. The evaluated pathogens were Staphylococcus epidermidis, Staphylococcus aureus, Pseudomonas aeruginosa, and Enterococcus faecalis. Bacteria were dispersed in PBS and diluted to a concentration of approximately 4 × 10 5 /ml. Riboflavin was added to a concentration of 0.01%. By spreading the solution on a microscope slide, a fluid film layer, with a thickness of around 400 mm, was formed and UVA exposure followed. Eight separate exposures were made for each strain (n = 8). The degree of elimination in resistant and non-resistant pathogens was compared. The bactericidal efficacy of exposure differed between the tested microorganisms, and the mean elimination ranged between 60 and 92%, being most extensive in both of the evaluated Pseudomonas strains and least in the E. faecalis strains. Similar reductions were seen in antibiotic-resistant and non-resistant strains, with the exception of S. aureus, in which the resistant strain metchicillin-resistant Staphylococcus aureus (MRSA) was eradicated in a greater extent than the non-resistant strain (P = 0.030). UVA-riboflavin settings used in PACK-CXL are effective in reducing both antibiotic-resistant and non-resistant bacteria. Antibiotic resistance does not appear to be protective against the photooxidative exposure. © 2016 Royal Australian and New Zealand College of Ophthalmologists.

Comparison of Hemostatic Efficacy of ChitoGauze and Combat Gauze in a Lethal Femoral Arterial Injury in Swine Model

DTIC Science & Technology

2010-04-01

range of gram positive and gram negative organisms, including methicillin resistant Staphylococcus aureus ATCC33591 (MRSA), Enterococcus faecalis...range of gram positive and gram negative organisms, including methicillin resistant Staphylococcus aureus ATCC33591 (MRSA), Enterococcus faecalis...control with less blood loss than Combat Gauze in this model. Report Documentation Page Form ApprovedOMB No. 0704-0188 Public reporting burden for

Frequency and expression of mutacin biosynthesis genes in isolates of Streptococcus mutans with different mutacin-producing phenotypes.

PubMed

Kamiya, Regianne Umeko; Höfling, José Francisco; Gonçalves, Reginaldo Bruno

2008-05-01

The aim of this study was to analyse the frequency and expression of biosynthesis genes in 47 Streptococcus mutans isolates with different mutacin-producing phenotypes. Detection of the frequency and expression of genes encoding mutacin types I, II, III and IV were carried out by PCR and semi-quantitative RT-PCR, respectively, using primers specific for each type of biosynthesis gene. In addition, a further eight genes encoding putative bacteriocins, designated bsm 283, bsm 299, bsm 423, bsm 1889c, bsm 1892c, bsm 1896, bsm 1906c and bsm 1914, were also screened. There was a high phenotypic diversity; some Streptococcus mutans isolates presented broad antimicrobial spectra against other Streptococcus mutans clinical isolates, including bacteria resistant to common antibiotics, as well as Staphylococcus aureus, Staphylococcus epidermidis, Enterococcus faecalis and Streptococcus pyogenes. The expression frequency of the bsm gene was higher than that of the previously characterized mutacins (I-IV). There was no positive correlation between the number of indicator strains inhibited (antimicrobial spectra) and the number of biosynthesis genes expressed (Spearman correlation test, r=-0.03, P>0.05). In conclusion, the high diversity of mutacin-producing phenotypes, associated with high frequency of expression of the biosynthesis genes screened, reveals a broad repertoire of genetic determinants encoding antimicrobial peptides that can act in different combinations.

Biofilm formation by Staphylococcus epidermidis on peritoneal dialysis catheters and the effects of extracellular products from Pseudomonas aeruginosa.

PubMed

Pihl, Maria; Arvidsson, Anna; Skepö, Marie; Nilsson, Martin; Givskov, Michael; Tolker-Nielsen, Tim; Svensäter, Gunnel; Davies, Julia R

2013-04-01

Biofilm formation by Staphylococcus epidermidis is a cause of infections related to peritoneal dialysis (PD). We have used a PD catheter flow-cell model in combination with confocal scanning laser microscopy and atomic force microscopy to study biofilm formation by S. epidermidis. Adherence to serum-coated catheters was four times greater than to uncoated ones, suggesting that S. epidermidis binds to serum proteins on the catheter surface. Pseudomonas aeruginosa biofilm supernatant interfered with the formation of a serum protein coat thereby reducing the capacity for biofilm formation in S. epidermidis. Supernatants from ΔpelA, ΔpslBCD and ΔrhlAB strains of P. aeruginosa showed no differences from the wild-type supernatant indicating that the effect on serum coat formation was not due to rhamnolipids or the PelA and PslBCD polysaccharides. Supernatant from P. aeruginosa also dispersed established S. epidermidis biofilms. Supernatants lacking PelA or PslBCD showed no differences from the wild type but that from a ΔrhlAB strain, showed reduced, but not abolished, capacity for dispersal. This suggests that rhamnolipids are involved but not wholly responsible for the effect. Thus, supernatants from P. aeruginosa contain promising substances for the prevention and treatment of biofilm infections, although further work is required to identity more active components. © 2013 Federation of European Microbiological Societies. Published by Blackwell Publishing Ltd. All rights reserved.

Staphylococcus epidermidis adherence to human amniotic membrane and to human, rabbit, and cat conjunctiva.

PubMed

John, Thomas; Allen, Sam; John, Andrea G; Lai, Cathy I; Carey, Roberta B

2003-06-01

To evaluate Staphylococcus epidermidis adherence to human amniotic membrane (HAM) and compare it with S epidermidis adherence to human, rabbit, and cat conjunctiva in vitro. Research laboratory, Loyola University Medical Center, Maywood, Illinois, USA. Commercially available HAM (N = 3) was used. Conjunctival specimens from humans, rabbits, and cats (n = 3 each) were processed similarly to HAM. The tissues were exposed to S epidermidis (3 x 10(8) colony-forming units per milliliter) for 0, 5, 30, and 90 minutes, rinsed in sterile saline, and processed for light, scanning (SEM), and transmission (TEM) electron microscopy. Scanning electron microscopy (x2000) was used to quantify adherent bacteria/mm(2) of tissue (SEM photographs = 144). The following mean levels (+/- SD) of adherent S epidermidis/mm(2) were found at 0, 5, 30, and 90 minutes: HAM, 3833 +/- 1570, 9060 +/- 2512, 15,431 +/- 10,752, and 30,315 +/- 14,803, respectively; human conjunctiva, 1493 +/- 672, 7218 +/- 3179, 17,273 +/- 7168, and 19,861 +/- 9624, respectively; rabbit conjunctiva, 3385 +/- 5074, 14,386 +/- 14,569, 15,283 +/- 13,679, and 20,113 +/- 24,016, respectively; and cat conjunctiva, 4032 +/- 2240, 12,345 +/- 3413, 8512 +/- 4032, and 19,214 +/- 5584, respectively. No statistically significant differences were found at any time point (P>.16). There was no statistically significant difference in the adherence of S epidermidis to HAM and to human, rabbit, and cat conjunctiva. Bacterial adherence to HAM may be clinically significant.

Quantification of polyphenols and evaluation of antimicrobial, analgesic and anti-inflammatory activities of aqueous and acetone-water extracts of Libidibia ferrea, Parapiptadenia rigida and Psidium guajava.

PubMed

de Araújo, Aurigena Antunes; Soares, Luiz Alberto Lira; Assunção Ferreira, Magda Rhayanny; de Souza Neto, Manoel André; da Silva, Giselle Ribeiro; de Araújo, Raimundo Fernandes; Guerra, Gerlane Coelho Bernardo; de Melo, Maria Celeste Nunes

2014-10-28

Vast numbers of plant species from northeastern Brazil have not yet been phytochemically or biologically evaluated. The goal of this work was to obtain, characterize and show the antimicrobial, analgesic and anti-inflammatory activities of aqueous and acetone-water extracts of Libidibia ferrea, Parapiptadenia rigida and Psidium guajava. The plant material (100g) was dried, and the crude extracts were obtained by using turbo-extraction (10%; w/v) with water or acetone:water (7:3, v/v) as the extraction solvent. High-performance liquid chromatography (HPLC) methods were used to screen the crude extracts for hydrolysable tannins (gallic acid) and condensed tannins (catechins). The antibacterial activity was evaluated by agar-diffusion and microdilution methods against Gram-positive strains (Staphylococcus aureus ATCC 25923, Staphylococcus epidermidis INCQS 00016, Enterococcus faecalis ATCC 29212 and a clinical isolate of methicillin-resistant Staphylococcus aureus) as well as Gram-negative strains (Escherichia coli ATCC 25922, Salmonella enteritidis INCQS 00258, Shigella flexneri and Klebsiella pneumoniae). To evaluate the anti-inflammatory activity, a leukocyte migration model was used. Analgesic activity was determined by the hot plate test and the acetic acid-induced abdominal writhing test. Data were analyzed by analysis of variance (ANOVA) at a significance level of 5%. Parapiptadenia rigida presented the highest amount of total polyphenols (35.82 ± 0.20%), while the greatest catechin content was found in the acetone-water extract of Psidium guajava (EAWPg; 1.04 μg/g). The largest amounts of catechins were found in the aqueous extract of Libidibia ferrea (EALf; 1.07 μg/g) and the acetone-water extract of Parapiptadenia rigida (EAWPr; 1.0 μg/g). All extracts showed activity against Gram-positive bacteria. The aqueous and acetone-water extracts of Psidium guajava showed the greatest inhibition zones in the agar diffusion tests. In the evaluation of the minimum inhibitory concentration (MIC), the most susceptible Gram-positive bacterium was Staphylococcus epidermidis and the most susceptible Gram-negative bacterium was Shigella flexneri. EAPg and EAWPg showed the greatest MIC values. All extracts were significant inhibitors of leukocyte migration (p<0.05). Using the writhing test, significant analgesic activity was found for EAPr (50 mg/kg), EAWPr (100 mg/kg and 200 mg/kg) and EAWPg (50 mg/kg) (p<0.05). Thus, the appropriate extraction procedure preserves the chemical components such as gallic acid and catechin, and showed antimicrobial, anti-inflammatory and analgesic properties. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

A high incidence of Staphylococcus aureus colonization in the external eyes of patients with atopic dermatitis.

PubMed

Nakata, K; Inoue, Y; Harada, J; Maeda, N; Watanabe, H; Tano, Y; Shimomura, Y; Harino, S; Sawa, M

2000-12-01

To determine the frequency distribution of bacteria on the external surface of eyes of patients with atopic dermatitis (AD) and to investigate the relationship between the frequency of bacterial colonization and the grade of atopy or ocular diseases associated with AD. Comparative cross-sectional study. Thirty-six AD patients (mean age, 24.5 years) and 16 nonatopic, age-matched control participants (mean age, 25.5 years). The eyelid margins and conjunctival sacs were scraped with sterile swabs. These samples were inoculated into aerobic and anaerobic culture media. The frequency distribution of bacteria isolated from the eyelid margins and conjunctival sacs. Bacteria isolated from AD patients were: Staphylococcus aureus in 21 of 36 patients (including methicillin-resistant Staphylococcus aureus in two patients); Staphylococcus epidermidis in two patients (including methicillin-resistant Staphylococcus epidermidis in one patient); other coagulase-negative Staphylococcus in six patients;alpha-streptococcus in three patients; Corynebacterium species in three patients; Neisseria species in two patients; and Propionibacterium acnes in one patient. From the nonatopic control participants, we isolated S. aureus in one patient, S. epidermidis in two patients and alpha-streptococcus in one patient. S. aureus was isolated from 67% of the AD patients, and any type of bacteria was isolated from 86% of the patients. These rates were significantly higher than those of nonatopic control participants (6% S. aureus and 25% any bacteria). There was no significant relationship between the frequency distribution of bacteria and the grade of atopy or associated ocular diseases. High rates of bacterial colonization, especially S. aureus, were found in the conjunctival sacs and eyelid margins of AD patients. In case management of AD patients, this unique distribution of bacteria must be carefully considered.

Species identification and susceptibility to 17 antibiotics of coagulase-negative staphylococci isolated from clinical specimens.

PubMed

Marsik, F J; Brake, S

1982-04-01

A total of 299 isolates of gram-positive, catalase-positive, coagulase-negative cocci were isolated from a variety of specimens collected from patients at a large university hospital, and 281 (94%) were identified as staphylococci by established methods. Using the scheme of Kloos and Schleifer, we determined the species of the coagulase-negative staphylococci. Staphylococcus epidermidis was the cause of all bacteremias and the most commonly isolated species from bone, joint, and wound infections. Staphylococcus haemolyticus was the second most common isolate from wound infections, and Staphylococcus saprophyticus was the most commonly isolated species from urinary tract infections. Antibiograms to 17 antimicrobial agents were performed by a microdilution technique, and the results revealed that S. epidermidis was resistant to a water spectrum of antimicrobial agents than the other species of staphylococci were.

Species identification and susceptibility to 17 antibiotics of coagulase-negative staphylococci isolated from clinical specimens.

PubMed Central

Marsik, F J; Brake, S

1982-01-01

A total of 299 isolates of gram-positive, catalase-positive, coagulase-negative cocci were isolated from a variety of specimens collected from patients at a large university hospital, and 281 (94%) were identified as staphylococci by established methods. Using the scheme of Kloos and Schleifer, we determined the species of the coagulase-negative staphylococci. Staphylococcus epidermidis was the cause of all bacteremias and the most commonly isolated species from bone, joint, and wound infections. Staphylococcus haemolyticus was the second most common isolate from wound infections, and Staphylococcus saprophyticus was the most commonly isolated species from urinary tract infections. Antibiograms to 17 antimicrobial agents were performed by a microdilution technique, and the results revealed that S. epidermidis was resistant to a water spectrum of antimicrobial agents than the other species of staphylococci were. PMID:7068839

Heterogeneous resistance to vancomycin in Staphylococcus epidermidis, Staphylococcus haemolyticus and Staphylococcus warneri clinical strains: characterisation of glycopeptide susceptibility profiles and cell wall thickening.

PubMed

Nunes, Ana Paula Ferreira; Teixeira, Lúcia Martins; Iorio, Natália Lopes Pontes; Bastos, Carla Callegário Reis; de Sousa Fonseca, Leila; Souto-Padrón, Thaís; dos Santos, Kátia Regina Netto

2006-04-01

The population analysis profile (PAP) method as well as analysis of autolytic activity and cellular ultrastructure by transmission electron microscopy (TEM) were used to characterise Staphylococcus epidermidis, Staphylococcus haemolyticus and Staphylococcus warneri clinical strains with reduced susceptibility to glycopeptides. All strains showed heterogeneous profiles to vancomycin and teicoplanin by the PAP method. Subpopulations that grew in the presence of high concentrations of each drug were selected from the PAP as derivative strains. Their glycopeptide minimal inhibitory concentrations (MICs) were determined and subsequently all parental and derivative strains were grown in one-half of the MIC of vancomycin or teicoplanin. An increase in cell wall thickness of all derivative strains was seen by TEM, with statistically significant values (P<0.01) compared with their respective parental strains. In general, variable rates of autolysis among the strains were observed. Cell wall thickness is an important factor involved in glycopeptide resistance and, in association with PAP results, confirmed the Brazilian coagulase-negative staphylococci clinical isolates as being heteroresistant to glycopeptides. Detection of these heteroresistant organisms is important in order to achieve more judicious use of vancomycin and teicoplanin in hospitals.

Nontoxic concentration of ceftazidime and flomoxef sodium for intravitreal use--evaluated by in-vitro ERG.

PubMed

Tanabe, J; Kitano, K; Suzuki, T; Okayama, Y; Mochizuki, K; Kawasaki, K

1990-01-01

The effects of ceftazidime (CAZ) and flomoxef sodium (FMOX) on the in-vitro electroretinogram (ERG) of albino rabbits were studied. The a-wave, the b-wave and the oscillatory potential (OP) were unchanged by 0.3mM (0.19mg/ml) CAZ-containing solution. The OP was suppressed by 0.5mM (0.32mg/ml) CAZ. The a-wave, the b-wave and the OP were unchanged by 0.5mM (0.26mg/ml) FMOX. The OP was suppressed and its peak latency was delayed by 2mM (0.52mg/ml) FMOX. The concentration of 0.3mM (0.19mg/ml) CAZ was higher than its minimum inhibitory concentration (MIC) against Staphylococcus aureus, Staphylococcus epidermidis, Pseudomonas aeruginosa, Serratia marcescens and Propionibacterium acnes. The concentration of 0.5mM (0.26mg/ml) FMOX was higher than its MIC against Staphylococcus aureus, Staphylococcus epidermidis, Serratia marcescens and Propionibacterium acnes.

Synthesis and In Vitro Activity of Polyhalogenated 2-phenylbenzimidazoles as a New Class of anti-MRSA and Anti-VRE Agents.

PubMed

Göker, Hakan; Karaaslan, Cigdem; Püsküllü, Mustafa Orhan; Yildiz, Sulhiye; Duydu, Yalcin; Üstündağ, Aylin; Yalcin, Can Özgür

2016-01-01

A series of novel polyhalogenated 2-phenylbenzimidazoles have been synthesized and evaluated for in vitro antistaphylococcal activity against drug-resistant bacterial strains (methicillin-resistant Staphylococcus aureus, and vancomycin-resistant Enterococcus faecium. Certain compounds inhibit bacterial growth perfectly. 11 was active than vancomycin (0.78 μg/mL) with the lowest MIC values with 0.19 μg/mL against methicillin-resistant Staphylococcus aureus, 8 and 35 exhibited best inhibitory activity against vancomycin-resistant Enterococcus faecium (1.56 μg/mL). The mechanism of action for this class of compounds appears to be different than clinically used antibiotics. These polyhalogenated benzimidazoles have potential for further investigation as a new class of potent anti-methicillin-resistant Staphylococcus aureus and anti-vancomycin-resistant Enterococcus faecium agents. © 2015 John Wiley & Sons A/S.

Insights into Comparative Antimicrobial Efficacies of Synthetic and Organic Agents: The Case of ZnS Nanoparticles and Zingiber officinale Rosc.

NASA Astrophysics Data System (ADS)

Obidi, O. F.; Nejo, A. O.; Ayeni, R. A.; Revaprasadu, N.

2018-03-01

The differences among the antimicrobial activities of synthetic nanoparticles (NPs), organic agents and conventional antibiotics against human pathogens are little known. We compared the antimicrobial activities of aqueous, ethanol and ethyl acetate extracts of Zingiber officinale rhizomes with ZnS NPs and tetracycline/nystatin using agar-diffusion techniques. Transmission electron microscopy (TEM), Fourier transform infrared (FTIR) and ultraviolet spectroscopy were used to characterize ZnS NPs. At 100 mg/ml, ethanol and ethyl acetate extract inhibited Acinetobacter baumannii, Salmonella typhimurium, Enterococcus faecium, Shigella flexneri, Klebsiella pneumoniae, Staphylococcus epidermidis and Candida albicans with zones of inhibition (ZOI) ranging between 0-42 mm and 0-39 mm, respectively. Candida albicans had a remarkable ZOI of 42 mm and 22 mm from ethanol and ZnS NPs compared with 20 mm from conventional nystatin. TEM and FTIR revealed spherically shaped polydispersed NPs with particle size of 12.5 nm and the role of banana peel extracts in ZnS NPs synthesis. Organic and synthetic NPs proved potential alternatives to conventional antimicrobial agents.

Insights into Comparative Antimicrobial Efficacies of Synthetic and Organic Agents: The Case of ZnS Nanoparticles and Zingiber officinale Rosc.

NASA Astrophysics Data System (ADS)

Obidi, O. F.; Nejo, A. O.; Ayeni, R. A.; Revaprasadu, N.

2018-06-01

The differences among the antimicrobial activities of synthetic nanoparticles (NPs), organic agents and conventional antibiotics against human pathogens are little known. We compared the antimicrobial activities of aqueous, ethanol and ethyl acetate extracts of Zingiber officinale rhizomes with ZnS NPs and tetracycline/nystatin using agar-diffusion techniques. Transmission electron microscopy (TEM), Fourier transform infrared (FTIR) and ultraviolet spectroscopy were used to characterize ZnS NPs. At 100 mg/ml, ethanol and ethyl acetate extract inhibited Acinetobacter baumannii, Salmonella typhimurium, Enterococcus faecium, Shigella flexneri, Klebsiella pneumoniae, Staphylococcus epidermidis and Candida albicans with zones of inhibition (ZOI) ranging between 0-42 mm and 0-39 mm, respectively. Candida albicans had a remarkable ZOI of 42 mm and 22 mm from ethanol and ZnS NPs compared with 20 mm from conventional nystatin. TEM and FTIR revealed spherically shaped polydispersed NPs with particle size of 12.5 nm and the role of banana peel extracts in ZnS NPs synthesis. Organic and synthetic NPs proved potential alternatives to conventional antimicrobial agents.

The in-vitro antimicrobial activities of some medicinal plants from Cameroon.

PubMed

Gangoué-Piéboji, J; Pegnyemb, D E; Niyitegeka, D; Nsangou, A; Eze, N; Minyem, C; Mbing, J Ngo; Ngassam, P; Tih, R Ghogomu; Sodengam, B L; Bodo, B

2006-04-01

The antimicrobial activities of 10 plant species (Voacanga africana, Crepis cameroonica, Plagiostyles africana, Crotalaria retusa, Mammea africana, Lophira lanceolata, Ochna afzelii, Ouratea elongata, Ou. flava and Ou. sulcata), each of which is currently used in the traditional medicine of Cameroon, were investigated in vitro. The activities of a methanol extract of each plant were tested, in disc-diffusion assays, against 37 reference or laboratory strains of seven species of microorganism (Staphylococcus aureus, S. epidermidis, Enterococcus hirae, Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa and Candida albicans). The minimal inhibitory concentrations of each extract were then estimated, against each of the more susceptible microorganisms (i.e. those giving an inhibition zone measuring at least 9 mm in diameter in the disc-diffusion assays), by agar dilution. Although, in the disc-diffusion assays, each of the 10 methanol extracts investigated displayed some degree of antimicrobial activity against at least one species of microorganism, no activity against the Gram-negative bacteria (Es. coli, K. pneumoniae and Ps. aeruginosa) was observed. The extract with the greatest antimicrobial activity was that of Pl. africana (Euphorbiaceae).

Microbial burden of some herbal antimalarials marketed at Elele, Rivers State.

PubMed

Tatfeng, Y M; Olama, E H; Ojo, T O

2009-12-30

Herbal antimalarials still remain an alternative to our traditional communities who can not afford orthodox antimalarials. This study was aimed at investigating the microbial quality of six herbal antimalarials using standard microbiological methods. Of the six preparations analyzed, "schnapps", palm wine and water were the media of preparation; the water base preparations recorded higher microbial load. The mean microbial load was 159.5 × 10(5) cfu/ml and 217.4 × 10(2)cfu/ml in water and alcohol base preparations respectively. The microbial profile of the preparations showed that the schnapps base preparations were predominantly contaminated with Bacillus sp (Aerobic spore bearers) and Mucor spp. The palm wine preparation harboured Bacillus sp, yeasts and Mucor spp while the water base preparations had several isolates such as Staphylococcus epidermidis, Pseudomonas aeruginosa, Escherichia coli 0157H7, Proteus mirabilis, Enterococcus feacalis, Serratia marcensces, Staph. aureus, Bacillus spp and Mucor spp. Conclusively, this study underlines the public health importance of these preparations given the high burden of such human pathogen as Ecoli O157H7, Ps aeruginosa, Stahp aureus, etc. in the preparations.

A comparative 18F-FDG PET/CT imaging of experimental Staphylococcus aureus osteomyelitis and Staphylococcus epidermidis foreign-body-associated infection in the rabbit tibia

PubMed Central

2012-01-01

Background 18F-FDG-PET imaging has emerged as a promising method in the diagnosis of chronic osteomyelitis commonly due to Staphylococcus aureus. The inaccuracy of 18 F-FDG-PET in the detection of periprosthetic joint infections may be related to the predominance of low-virulent S. epidermidis strains as the causative pathogen. We have compared the18F-FDG-PET characteristics of S. aureus osteomyelitis and foreign-body-associated S. epidermidis infections under standardized laboratory conditions. Methods Twenty-two rabbits were randomized into three groups. In group 1, a localized osteomyelitis model induced with a clinical strain of S. aureus was applied. In groups 2 and 3, a foreign-body-associated infection model induced with a clinical or laboratory strain of S. epidermidis was applied. A small block of bone cement was surgically introduced into the medullary cavity of the proximal tibia followed by peri-implant injection of S. aureus (1 × 105 CFU/mL) or one of the two S. epidermidis (1 × 109 CFU/mL) strains with an adjunct injection of aqueous sodium morrhuate. In group 1, the cement block was surgically removed at 2 weeks but left in place in groups 2 and 3 in order to mimic foreign-body-associated S. epidermidis infections. At 8 weeks, the animals were imaged using 18 F-FDG PET/CT. The presence of bacterial infection was confirmed by cultures, and the severity of bone infections was graded by means of radiography, peripheral quantitative CT, and semi-quantitative histology. Results The S. aureus strain caused constantly culture-positive osteomyelitis. The clinical S. epidermidis strain resulted in foreign-body-associated infections, while the laboratory S. epidermidis strain (ATCC 35983) induced only occasionally culture-positive infections. There was a correlation (r = 0.645; P = 0.013) between semi-quantitative score of leukocyte infiltration and the 18 F-FDG uptake in animals with positive cultures. Standardized uptake value (SUV) of the infected bones was twofold (P < 0.001) in S. aureus animals compared with S. epidermidis animals, but there was only a trend (P = 0.053, ANOVA) in the differences of the corresponding SUV ratios. This was due to the altered 18 F-FDG uptake of the contralateral tibias probably reflecting a systemic impact of severe osteomyelitis. Conclusion The peri-implant inoculation of S. epidermidis, reflecting low virulence of the pathogen and limited leukocyte infiltration, was characterized by low 18 F-FDG uptake. PMID:22824200

Sub-inhibitory tigecycline concentrations induce extracellular matrix binding protein Embp dependent Staphylococcus epidermidis biofilm formation and immune evasion.

PubMed

Weiser, Julian; Henke, Hanae A; Hector, Nina; Both, Anna; Christner, Martin; Büttner, Henning; Kaplan, Jeffery B; Rohde, Holger

2016-09-01

Biofilm-associated Staphylococcus epidermidis implant infections are notoriously reluctant to antibiotic treatment. Here we studied the effect of sub-inhibitory concentrations of penicillin, oxacillin, vancomycin, daptomycin, linezolid and tigecycline on S. epidermidis 1585 biofilm formation, expression of extracellular matrix binding protein (Embp) and potential implications for S. epidermidis - macrophage interactions. Penicillin, vancomycin, daptomycin, and linezolid had no biofilm augmenting effect at any of the concentrations tested. In contrast, at sub-inhibitory concentrations tigecycline and oxacillin exhibited significant biofilm inducing activity. In S. epidermidis 1585, SarA is a negative regulator of giant 1 MDa Embp, and down regulation of sarA induces Embp-dependent assembly of a multi-layered biofilm architecture. Dot blot immune assays, confocal laser scanning microscopy, and qPCR showed that under biofilm inducing conditions, tigecycline augmented embp expression compared to the control grown without antibiotics. Conversely, expression of regulator sarA was suppressed, suggesting that tigecycline exerts its effects on embp expression through SarA. Tigecycline failed to induce biofilm formation in embp transposon mutant 1585-M135, proving that under these conditions Embp up-regulation is necessary for biofilm accumulation. As a functional consequence, tigecycline induced biofilm formation significantly impaired the up-take of S. epidermidis by mouse macrophage-like cell line J774A.1. Our data provide novel evidence for the molecular basis of antibiotic induced biofilm formation, a phenotype associated with inherently increased antimicrobial tolerance. While this could explain failure of antimicrobial therapies, persistence of S. epidermidis infections in the presence of sub-inhibitory antimicrobials is additionally propelled by biofilm-related impairment of macrophage-mediated pathogen eradication. Copyright © 2016 Elsevier GmbH. All rights reserved.

Effects of alcohols, povidone-iodine and hydrogen peroxide on biofilms of Staphylococcus epidermidis.

PubMed

Presterl, Elisabeth; Suchomel, Miranda; Eder, Michaela; Reichmann, Sonja; Lassnigg, Andrea; Graninger, Wolfgang; Rotter, Manfred

2007-08-01

To test the effects of several biocides [N-propanol, a commercially available propanol/ethanol/chlorhexidine mixture, polyvinylpyrolidone (povidone-iodine) and hydrogen peroxide] on established biofilms of Staphylococcus epidermidis isolated from patients with cardiac implant infections and catheter-related bacteraemia. Biofilms were grown in microtitre plates for 24 h, dyed and stained with Crystal Violet. The mean optical density (OD) and the OD ratio (ODr=OD of the treated biofilm/OD of the untreated biofilm) were used for quantification. Biofilms were incubated with 60% (v/v) N-propanol, the mixture of propanol/ethanol/chlorhexidine, hydrogen peroxide at three concentrations (0.5%, 3% and 5%, v/v) and povidone-iodine for 1, 5, 15, 30 and 60 min. Unstained biofilms were sonicated and plated on Columbia agar for time-kill curves. S. epidermidis skin isolates from healthy volunteers were used as controls. Biofilm ODs of the clinical S. epidermidis isolates and the isolates from the healthy volunteers were significantly different (1.17+/-0.512 versus 0.559+/-0.095, respectively; mean+/-SD) (P<0.01). No viable S. epidermidis was detected in biofilms treated with the alcohols, N-propanol or the propanol/ethanol/chlorhexidine mixture. Incubation with povidone-iodine and hydrogen peroxide 3% and 5% led to a log reduction of the viable cells of >5 after incubation for 5 min, however, up to 10(3) viable cells were detected in four isolates after 30 min of incubation with povidone-iodine. S. epidermidis obtained from infected implants forms thicker biofilms than that of healthy volunteers. Hydrogen peroxide, at a concentration of 3% and 5%, and alcohols rapidly eradicate S. epidermidis biofilms, whereas povidone-iodine is less effective.

Inhibitory efficacy of geraniol on biofilm formation and development of adaptive resistance in Staphylococcus epidermidis RP62A.

PubMed

Kannappan, Arunachalam; Sivaranjani, Murugesan; Srinivasan, Ramanathan; Rathna, Janarthanam; Pandian, Shunmugiah Karutha; Ravi, Arumugam Veera

2017-10-01

The current study has been designed to delineate the efficacy of geraniol (GE) on biofilm formation in Staphylococcus epidermidis as well as the effect of subinhibitory concentrations of GE on the development of adaptive resistance. Biofilm biomass quantification assay was performed to evaluate the antibiofilm activity of GE against S. epidermidis. Microscopic observation of biofilms and extracellular polymeric substance (EPS), slime and cell surface hydrophobicity (CSH) production were also studied to support the antibiofilm potential of GE. In addition, S. epidermidis was examined for its adaptive resistance development upon continuous exposure of GE at its subinhibitory concentrations.Results/Key findings. The MIC of GE against S. epidermidis was 512 µg ml -1 . Without hampering the growth of the pathogen, GE at its sub-MICs (50, 100, 150 and 200 µg ml -1 ) exhibited a dose-dependent increase in antibiofilm activity. The minimal biofilm inhibitory concentration (MBIC) of GE was found to be 200 µg ml -1 with a maximum biofilm inhibition of 85 %. Disintegrated biofilm architecture, reduced EPS, slime and CSH production validated the antibiofilm efficacy of GE. Although the action of GE on preformed biofilm is limited, a 2,3-bis(2-methoxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-5-carboxanilide (XTT) reduction assay and live/dead cell staining method revealed reduction in the viability (47 %) of biofilm inhabitants at 2×MIC concentration. Sequential exposure of S. epidermidis to the sub-MICs of GE resulted in poor development of adaptive resistance with diminished biofilm formation. The present study highlights the potential of GE as a suitable candidate for the control of biofilm-mediated S. epidermidis infections.

Synergy of ambroxol with vancomycin in elimination of catheter-related Staphylococcus epidermidis biofilm in vitro and in vivo.

PubMed

Zhang, Yunhui; Fu, Yakun; Yu, Jialin; Ai, Qing; Li, Junshuai; Peng, Ningning; Song, Sijie; He, Yu; Wang, Zhengli

2015-11-01

Central venous catheters are widely used in neonatal intensive care units (NICUs) nowadays. The commonest cause of catheter-related bloodstream infections (CRBSIs) is coagulase-negative staphylococci (CoNS). Ambroxol, an active metabolite of bromhexine, exhibits antimicrobial activity against strains producing biofilm and enhances the bactericidal effect of some antibiotic by breaking the structure of biofilm. In this study, we aimed to determine the effect of ambroxol with vancomycin on the biofilm of Staphylococcus epidermidis (S. epidermidis) in vitro and in vivo. In the in vitro study, the biofilm of S. epidermidis was assessed by XTT reduction assay and analysed by confocal laser scanning microscopy (CLSM). In the in vivo study, a rabbit model of CRBSIs was created by intravenous intubation with a tube covered with S. epidermidis biofilm. The rabbits received one of the following four treatments by means of antibiotic lock therapy: normal heparin, ambroxol, vancomycin, or vancomycin plus ambroxol each for 3 days. The microstructure of the biofilm was assessed by scanning electron microscopy (SEM). The number of bacterial colonies in the organs (liver, heart, and kidney) and on the intravenous tubes was measured on agar plates. Pathological changes in the organs (liver, heart, and kidney) were observed with Hematoxylin-Eosin staining. The ambroxol exhibits significant efficacy to potentiate the bactericidal effect of vancomycin on S. epidermidis biofilm both in vitro and in vivo. The antibiotic lock therapy using a combination of ambroxol and vancomycin reveals a high ability to eradicate S. epidermidis biofilms in vivo. These results provide the basis of a useful anti-infection strategy for the treatment of CRBSIs. Copyright © 2015 Japanese Society of Chemotherapy and The Japanese Association for Infectious Diseases. Published by Elsevier Ltd. All rights reserved.

Ses proteins as possible targets for vaccine development against Staphylococcus epidermidis infections.

PubMed

Hofmans, Dorien; Khodaparast, Laleh; Khodaparast, Ladan; Vanstreels, Els; Shahrooei, Mohammad; Van Eldere, Johan; Van Mellaert, Lieve

2018-05-09

The opportunistic pathogen Staphylococcus epidermidis is progressively involved in device-related infections. Since these infections involve biofilm formation, antibiotics are not effective. Conversely, a vaccine can be advantageous to prevent these infections. In view of vaccine development, predicted surface proteins were evaluated on their potential as a vaccine target. Immunoglobulins directed against S. epidermidis surface proteins SesB, M, O, Q and R, were used to firstly affirm their surface location. Further, inhibitory effects of these IgGs on biofilm formation were determined in vitro on polystyrene and polyurethane surfaces and in vivo using a subcutaneous catheter mouse model. We also examined the opsonophagocytic capacity of these IgGs. Surface localization of the five Ses proteins was demonstrated both for planktonic and sessile cells, though to a variable extent. Ses-specific IgGs added to planktonic cells had a variable inhibitory effect on cell adhesion to polystyrene, while only anti-SesO IgGs decreased cell attachment to polyurethane catheters. Although phagocytic killing was only obtained after opsonisation with SesB-specific IgGs, a significant reduction of in vivo formed biofilms was observed after administration of SesB-, SesM- and SesO-specific IgGs. Regardless of their characterization or function, S. epidermidis surface proteins can be adequate targets for vaccine development aiming the prevention of device-related infections caused by invasive S. epidermidis strains. Copyright © 2018 Elsevier Ltd. All rights reserved.

Inhibition of Staphylococcus epidermidis Biofilm Formation by Traditional Thai Herbal Recipes Used for Wound Treatment.

PubMed

Chusri, S; Sompetch, K; Mukdee, S; Jansrisewangwong, S; Srichai, T; Maneenoon, K; Limsuwan, S; Voravuthikunchai, S P

2012-01-01

Development of biofilm is a key mechanism involved in Staphylococcus epidermidis virulence during device-associated infections. We aimed to investigate antibiofilm formation and mature biofilm eradication ability of ethanol and water extracts of Thai traditional herbal recipes including THR-SK004, THR-SK010, and THR-SK011 against S. epidermidis. A biofilm forming reference strain, S. epidermidis ATCC 35984 was employed as a model for searching anti-biofilm agents by MTT reduction assay. The results revealed that the ethanol extract of THR-SK004 (THR-SK004E) could inhibit the formation of S. epidermidis biofilm on polystyrene surfaces. Furthermore, treatments with the extract efficiently inhibit the biofilm formation of the pathogen on glass surfaces determined by scanning electron microscopy and crystal violet staining. In addition, THR-SK010 ethanol extract (THR-SK010E; 0.63-5 μg/mL) could decrease 30 to 40% of the biofilm development. Almost 90% of a 7-day-old staphylococcal biofilm was destroyed after treatment with THR-SK004E (250 and 500 μg/mL) and THR-SK010E (10 and 20 μg/mL) for 24 h. Therefore, our results clearly demonstrated THR-SK004E could prevent the staphylococcal biofilm development, whereas both THR-SK004E and THR-SK010E possessed remarkable eradication ability on the mature staphylococcal biofilm.

Antagonism between Staphylococcus epidermidis and Propionibacterium acnes and its genomic basis.

PubMed

Christensen, Gitte J M; Scholz, Christian F P; Enghild, Jan; Rohde, Holger; Kilian, Mogens; Thürmer, Andrea; Brzuszkiewicz, Elzbieta; Lomholt, Hans B; Brüggemann, Holger

2016-02-29

Propionibacterium acnes and Staphylococcus epidermidis live in close proximity on human skin, and both bacterial species can be isolated from normal and acne vulgaris-affected skin sites. The antagonistic interactions between the two species are poorly understood, as well as the potential significance of bacterial interferences for the skin microbiota. Here, we performed simultaneous antagonism assays to detect inhibitory activities between multiple isolates of the two species. Selected strains were sequenced to identify the genomic basis of their antimicrobial phenotypes. First, we screened 77 P. acnes strains isolated from healthy and acne-affected skin, and representing all known phylogenetic clades (I, II, and III), for their antimicrobial activities against 12 S. epidermidis isolates. One particular phylogroup (I-2) exhibited a higher antimicrobial activity than other P. acnes phylogroups. All genomes of type I-2 strains carry an island encoding the biosynthesis of a thiopeptide with possible antimicrobial activity against S. epidermidis. Second, 20 S. epidermidis isolates were examined for inhibitory activity against 25 P. acnes strains. The majority of S. epidermidis strains were able to inhibit P. acnes. Genomes of S. epidermidis strains with strong, medium and no inhibitory activities against P. acnes were sequenced. Genome comparison underlined the diversity of S. epidermidis and detected multiple clade- or strain-specific mobile genetic elements encoding a variety of functions important in antibiotic and stress resistance, biofilm formation and interbacterial competition, including bacteriocins such as epidermin. One isolate with an extraordinary antimicrobial activity against P. acnes harbors a functional ESAT-6 secretion system that might be involved in the antimicrobial activity against P. acnes via the secretion of polymorphic toxins. Taken together, our study suggests that interspecies interactions could potentially jeopardize balances in the skin microbiota. In particular, S. epidermidis strains possess an arsenal of different mechanisms to inhibit P. acnes. However, if such interactions are relevant in skin disorders such as acne vulgaris remains questionable, since no difference in the antimicrobial activity against, or the sensitivity towards S. epidermidis could be detected between health- and acne-associated strains of P. acnes.

Chocolate agar, a differential medium for gram-positive cocci.

PubMed Central

Gunn, B A

1984-01-01

Reactions incurred on chocolate agar by gram-positive cocci were correlated with species identity. Darkening and clearing of the medium was usually associated with the species Staphylococcus epidermidis, Staphylococcus aureus, Staphylococcus simulans, and Streptococcus faecalis. Yellowing of chocolate agar was associated with alpha-hemolytic species of Streptococcus. The study demonstrated that reactions occurring on chocolate agar are useful in identifying gram-positive cocci. PMID:6490866

Ex vivo study of serum bactericidal titers and killing rates of daptomycin (LY146032) combined or not combined with amikacin compared with those of vancomycin.

PubMed Central

Van der Auwera, P

1989-01-01

Twelve volunteers, in two groups of six, received daptomycin at a dose of 1 or 2 mg/kg. In addition, they received in a randomly allocated order amikacin (500 mg), daptomycin-amikacin, and vancomycin (500 mg). Thirty-five clinical isolates, including Staphylococcus aureus, S. epidermidis, Corynebacterium sp. group JK, and Enterococcus faecalis, were tested in vitro for the measure of the serum bactericidal titers and killing rates. The mean peak concentrations of daptomycin in serum 1 h after the administration of 1 and 2 mg/kg were 11 and 20 micrograms/ml, respectively. At 24 h after the administration of 2 mg/kg, the mean level in serum was 1.9 micrograms/ml, which is higher than the MICs for susceptible pathogens. Daptomycin and amikacin provided identical concentrations in serum whether given alone or in combination. Among the six regimens tested, those including daptomycin provided the highest and the most prolonged serum bactericidal titers against S. aureus, S. epidermidis, and E. faecalis. The killing rates measured by the killing curves were correlated with the concentration/MIC and concentration/MBC ratios of daptomycin for all strains tested. Significant killing occurred once the concentration of daptomycin in the serum 4- to 6-fold the MIC or 1- to 1.2-fold the MBC. The combination of daptomycin and amikacin had no effect on either the serum bactericidal titers or the rates of killing. Only vancomycin provided significant killing of the strains of Corynebacterium sp. group JK. PMID:2556079

Antimicrobial susceptibilities and population structure of Staphylococcus epidermidis associated with ovine mastitis.

PubMed

Onni, Toniangelo; Sanna, Giovanna; Larsen, Jesper; Tola, Sebastiana

2011-02-24

Intramammary infections are a serious problem for dairy sheep farms, and Staphylococcus epidermidis is one of the main etiological agents of ovine mastitis. In this work, 131 S. epidermidis isolates, collected from 2201 dairy Sarda sheep belonging to 14 flocks with high somatic cell count scores, were studied. The flocks were located in diverse geographical areas of Sardinia, Italy. The aim of study was to assess the susceptibility of isolates to 13 antimicrobial agents, many of which are frequently used in mastitis therapy. Oxacillin was used for detecting methicillin-resistant S. epidermidis (MRSE) by disk diffusion test. Thirty-eight percent of the isolates (n=50) were resistant to penicillin, 7.6% (n=10) were resistant to tetracycline, and 2.3% (n=3) were resistant to both penicillin and tetracycline (PTRSE). Two isolates were resistant to five antimicrobials including methicillin. Analysis of staphylococcal cassette chromosome mec (SCCmec) elements showed that both MRSE isolates harbored SCCmec type IVa. Based on pulsed-field gel electrophoresis (PFGE) typing by SmaI macrorestriction, S. epidermidis isolates were grouped into four clusters at 75% similarity level. The two multi-drug resistant MRSE isolates displayed distinct PFGE patters. This study indicates that S. epidermidis isolates from sheep milk samples may accumulate resistance markers for different antimicrobial agents. Furthermore, the occurrence of PTRSE and MRSE suggests to adopt adequate hygienic measures when handling animals with intramammary infections, in order to prevent spreading PTRSE and MRSE strains to humans through direct contact and/or consumption of contaminated food. Copyright © 2010 Elsevier B.V. All rights reserved.

Secondary structure and phylogeny of Staphylococcus and Micrococcus 5S rRNAs.

PubMed Central

Dekio, S; Yamasaki, R; Jidoi, J; Hori, H; Osawa, S

1984-01-01

Nucleotide sequences of 5S rRNAs from four bacteria, Staphylococcus aureus Smith (diffuse), Staphylococcus epidermidis ATCC 14990, Micrococcus luteus ATCC 9341 and Micrococcus luteus ATCC 4698, were determined. The secondary structural models of S. aureus and S. epidermidis sequences showed characteristics of the gram-positive bacterial 5S rRNA (116-N type [H. Hori and S. Osawa, Proc. Natl. Acad. Sci. U.S.A. 76:381-385, 1979]). Those of M. luteus ATCC 9341 and M. luteus ATCC 4698 together with that of Streptomyces griseus (A. Simoncsits, Nucleic Acids Res. 8:4111-4124, 1980) showed intermediary characteristics between the gram-positive and gram-negative (120-N type [H. Hori and S. Osawa, 1979]) 5S rRNAs. This and previous studies revealed that there exist at least three major groups of eubacteria having distinct 5S rRNA and belonging to different stems in the 5S rRNA phylogenic tree. PMID:6735981

Rapid depletion of dissolved oxygen in 96-well microtiter plate Staphylococcus epidermidis biofilm assays promotes biofilm development and is influenced by inoculum cell concentration.

PubMed

Cotter, John J; O'Gara, James P; Casey, Eoin

2009-08-01

Biofilm-related research using 96-well microtiter plates involves static incubation of plates indiscriminate of environmental conditions, making oxygen availability an important variable which has not been considered to date. By directly measuring dissolved oxygen concentration over time we report here that dissolved oxygen is rapidly consumed in Staphylococcus epidermidis biofilm cultures grown in 96-well plates irrespective of the oxygen concentration in the gaseous environment in which the plates are incubated. These data indicate that depletion of dissolved oxygen during growth of bacterial biofilm cultures in 96-well plates may significantly influence biofilm production. Furthermore higher inoculum cell concentrations are associated with more rapid consumption of dissolved oxygen and higher levels of S. epidermidis biofilm production. Our data reveal that oxygen depletion during bacterial growth in 96-well plates may significantly influence biofilm production and should be considered in the interpretation of experimental data using this biofilm model.

Structure, Mechanics, and Instability of Fibrin Clot Infected with Staphylococcus epidermidis.

PubMed

Ma, Tianhui Maria; VanEpps, J Scott; Solomon, Michael J

2017-11-07

Health care-associated infection, over half of which can be attributed to indwelling medical devices, is a strong risk factor for thromboembolism. Although most experimental models of medical device infection draw upon isolated bacterial biofilms, in fact there is no infection without host protein contribution. Here we study, to our knowledge, a new model for medical device infection-that of an infected fibrin clot-and show that the common blood-borne pathogen Staphylococcus epidermidis influences this in vitro model of a blood clot mechanically and structurally on both microscopic and macroscopic scales. Bacteria present during clot formation produce a visibly disorganized microstructure that increases clot stiffness and triggers mechanical instability over time. Our results provide insight into the observed correlation between medical device infection and thromboembolism; the increase in model clot heterogeneity shows that S. epidermidis can rupture a fibrin clot. The resultant embolization of the infected clot can contribute to the systemic dissemination of the pathogen. Copyright © 2017 Biophysical Society. Published by Elsevier Inc. All rights reserved.

Effect of farnesol on structure and composition of Staphylococcus epidermidis biofilm matrix.

PubMed

Gomes, Fernanda; Teixeira, Pilar; Cerca, Nuno; Azeredo, Joana; Oliveira, Rosário

2011-10-01

Staphylococcus epidermidis is the most frequent cause of nosocomial sepsis and catheter-related infections in which biofilm formation is considered to be one of the main virulence mechanisms. Moreover, their increased resistance to conventional antibiotic therapy enhances the need to develop new therapeutical agents. Farnesol, a natural sesquiterpenoid present in many essential oils, has been described as impairing bacterial growth. The aim of this study was to evaluate the effect of farnesol on the structure and composition of biofilm matrix of S. epidermidis. Biofilms formed in the presence of farnesol (300 μM) contained less biomass, and displayed notable changes in the composition of the biofilm matrix. Changes in the spacial structure were also verified by confocal scanning laser microscopy (CSLM). The results obtained by the quantification of extracellular polymers and by wheat germ agglutinin (WGA) fluorescent detection of glycoproteins containing β(1→4)-N-acetyl-D: -glucosamine support the hypothesis that farnesol causes disruption of the cytoplasmic membrane and consequently release of cellular content.

Antimicrobial Activity of Pomegranate and Green Tea Extract on Propionibacterium Acnes, Propionibacterium Granulosum, Staphylococcus Aureus and Staphylococcus Epidermidis.

PubMed

Li, Zhaoping; Summanen, Paula H; Downes, Julia; Corbett, Karen; Komoriya, Tomoe; Henning, Susanne M; Kim, Jenny; Finegold, Sydney M

2015-06-01

We used pomegranate extract (POMx), pomegranate juice (POM juice) and green tea extract (GT) to establish in vitro activities against bacteria implicated in the pathogenesis of acne. Minimum inhibitory concentrations (MIC) of 94 Propionibacterium acnes, Propionibacterium granulosum, Staphylococcus aureus, and Staphylococcus epidermidis strains were determined by Clinical and Laboratory Standards Institute-approved agar dilution technique. Total phenolics content of the phytochemicals was determined using the Folin-Ciocalteu method and the polyphenol composition by HPLC. Bacteria were identified by 16S rRNA sequence analysis. GT MIC of 400 μg/ml or less was obtained for 98% of the strains tested. 64% of P. acnes strains had POMx MICs at 50 μg/ml whereas 36% had MIC >400 μg/ml. POMx, POM juice, and GT showed inhibitory activity against all the P. granulosum strains at ≤100 μg/ml. POMx and GT inhibited all the S. aureus strains at 400 μg/ml or below, and POM juice had an MIC of 200 μg/ml against 17 S. aureus strains. POMx inhibited S. epidermidis strains at 25 μg/ml, whereas POM juice MICs were ≥200 μg/ml. The antibacterial properties of POMx and GT on the most common bacteria associated with the development and progression of acne suggest that these extracts may offer a better preventative/therapeutic regimen with fewer side effects than those currently available.

Glycerol Monolaurate Inhibits Lipase Production by Clinical Ocular Isolates Without Affecting Bacterial Cell Viability.

PubMed

Flanagan, Judith Louise; Khandekar, Neeta; Zhu, Hua; Watanabe, Keizo; Markoulli, Maria; Flanagan, John Terence; Papas, Eric

2016-02-01

We sought to determine the relative lipase production of a range of ocular bacterial isolates and to assess the efficacy of glycerol monolaurate (GML) in inhibiting this lipase production in high lipase-producing bacteria without affecting bacterial cell growth. Staphylococcus aureus,Staphylococcus epidermidis,Propionibacterium acnes, and Corynebacterium spp. were inoculated at a density of 10(6)/mL in varying concentrations of GML up to 25 μg/mL for 24 hours at 37 °C with constant shaking. Bacterial suspensions were centrifuged, bacterial cell density was determined, and production of bacterial lipase was quantified using a commercial lipase assay kit. Staphylococcus spp. produced high levels of lipase activity compared with P. acnes and Corynebacterium spp. GML inhibited lipase production by Staphylococcal spp. in a dose-dependent manner, with S. epidermidis lipase production consistently more sensitive to GML than S. aureus. Glycerol monolaurate showed significant (P < 0.05) lipase inhibition above concentrations of 15 μg/mL in S. aureus and was not cytotoxic up to 25 μg/mL. For S. epidermidis, GML showed significant (P < 0.05) lipase inhibition above 7.5 μg/mL. Lipase activity varied between species and between strains. Staphylococcal spp. produced higher lipase activity compared with P. acnes and Corynebacterium spp. Glycerol monolaurate inhibited lipase production by S. aureus and S. epidermidis at concentrations that did not adversely affect bacterial cell growth. GML can be used to inhibit ocular bacterial lipase production without proving detrimental to commensal bacteria viability.

An Enterotoxin-Bearing Pathogenicity Island in Staphylococcus epidermidis▿†

PubMed Central

Madhusoodanan, Jyoti; Seo, Keun Seok; Remortel, Brian; Park, Joo Youn; Hwang, Sun Young; Fox, Lawrence K.; Park, Yong Ho; Deobald, Claudia F.; Wang, Dan; Liu, Song; Daugherty, Sean C.; Gill, Ann Lindley; Bohach, Gregory A.; Gill, Steven R.

2011-01-01

Cocolonization of human mucosal surfaces causes frequent encounters between various staphylococcal species, creating opportunities for the horizontal acquisition of mobile genetic elements. The majority of Staphylococcus aureus toxins and virulence factors are encoded on S. aureus pathogenicity islands (SaPIs). Horizontal movement of SaPIs between S. aureus strains plays a role in the evolution of virulent clinical isolates. Although there have been reports of the production of toxic shock syndrome toxin 1 (TSST-1), enterotoxin, and other superantigens by coagulase-negative staphylococci, no associated pathogenicity islands have been found in the genome of Staphylococcus epidermidis, a generally less virulent relative of S. aureus. We show here the first evidence of a composite S. epidermidis pathogenicity island (SePI), the product of multiple insertions in the genome of a clinical isolate. The taxonomic placement of S. epidermidis strain FRI909 was confirmed by a number of biochemical tests and multilocus sequence typing. The genome sequence of this strain was analyzed for other unique gene clusters and their locations. This pathogenicity island encodes and expresses staphylococcal enterotoxin C3 (SEC3) and staphylococcal enterotoxin-like toxin L (SElL), as confirmed by quantitative reverse transcription-PCR (qRT-PCR) and immunoblotting. We present here an initial characterization of this novel pathogenicity island, and we establish that it is stable, expresses enterotoxins, and is not obviously transmissible by phage transduction. We also describe the genome sequence, excision, replication, and packaging of a novel bacteriophage in S. epidermidis FRI909, as well as attempts to mobilize the SePI element by this phage. PMID:21317317

Antimicrobial effects of Thai medicinal plants against acne-inducing bacteria.

PubMed

Chomnawang, Mullika Traidej; Surassmo, Suvimol; Nukoolkarn, Veena S; Gritsanapan, Wandee

2005-10-03

Propionibacterium acnes and Staphylococcus epidermidis have been recognized as pus-forming bacteria triggering an inflammation in acne. The present study was conducted to evaluate antimicrobial activities of Thai medicinal plants against these etiologic agents of acne vulgaris. Crude extracts were tested for antimicrobial activities by disc diffusion and broth dilution methods. The results from the disc diffusion method showed that 13 medicinal plants could inhibit the growth of Propionibacterium acnes. Among those, Senna alata, Eupatorium odoratum, Garcinia mangostana, and Barleria lupulina had strong inhibitory effects. Based on a broth dilution method, the Garcinia mangostana extract had the greatest antimicrobial effect. The MIC values were the same (0.039 mg/ml) for both bacterial species and the MBC values were 0.039 and 0.156 mg/ml against Propionibacterium acnes and Staphylococcus epidermidis, respectively. In bioautography assay, the Garcinia mangostana extract produced strong inhibition zones against Propionibacterium acnes. Antimicrobial activity from fractions of column chromatography revealed one of the active compounds in Garcinia mangostana could be mangostin, a xanthone derivative. Taken together, our data indicated that Garcinia mangostana had a strong inhibitory effect on Propionibacterium acnes and Staphylococcus epidermidis. Therefore, this plant would be an interesting topic for further study and possibly for an alternative treatment for acne.

Synthesis and surface immobilization of antibacterial hybrid silver-poly(l-lactide) nanoparticles

NASA Astrophysics Data System (ADS)

Taheri, Shima; Baier, Grit; Majewski, Peter; Barton, Mary; Förch, Renate; Landfester, Katharina; Vasilev, Krasimir

2014-08-01

Infections associated with medical devices are a substantial healthcare problem. Consequently, there has been increasing research and technological efforts directed toward the development of coatings that are capable of preventing bacterial colonization of the device surface. Herein, we report on novel hybrid silver loaded poly(L-lactic acid) nanoparticles (PLLA-AgNPs) with narrowly distributed sizes (17 ± 3 nm) prepared using a combination of solvent evaporation and mini-emulsion technology. These particles were then immobilized onto solid surfaces premodified with a thin layer of allylamine plasma polymer (AApp). The antibacterial efficacy of the PLLA-AgNPs nanoparticles was studied in vitro against both gram-positive (Staphylococcus epidermidis) and gram-negative (Escherichia coli) bacteria. The minimal inhibitory concentration values against Staphylococcus epidermidis and Escherichia coli were 0.610 and 1.156 μg · mL-1, respectively. The capacity of the prepared coatings to prevent bacterial surface colonization was assessed in the presence of Staphylococcus epidermidis, which is a strong biofilm former that causes substantial problems with medical device associated infections. The level of inhibition of bacterial growth was 98%. The substrate independent nature and the high antibacterial efficacy of coatings presented in this study may offer new alternatives for antibacterial coatings for medical devices.

MALDI-TOF Mass Spectrometry: A Powerful Tool for Clinical Microbiology at Hôpital Principal de Dakar, Senegal (West Africa)

PubMed Central

Lo, Cheikh I.; Fall, Bécaye; Sambe-Ba, Bissoume; Diawara, Silman; Gueye, Mamadou W.; Mediannikov, Oleg; Sokhna, Cheikh; Faye, Ngor; Diemé, Yaya; Wade, Boubacar; Raoult, Didier; Fenollar, Florence

2015-01-01

Our team in Europe has developed the routine clinical laboratory identification of microorganisms by matrix-assisted laser desorption ionization time-of-flight (MALDI-TOF) mass spectrometry (MS). To evaluate the utility of MALDI-TOF MS in tropical Africa in collaboration with local teams, we installed an apparatus in the Hôpital Principal de Dakar (Senegal), performed routine identification of isolates, and confirmed or completed their identification in France. In the case of discordance or a lack of identification, molecular biology was performed. Overall, 153/191 (80.1%) and 174/191 (91.1%) isolates yielded an accurate and concordant identification for the species and genus, respectively, with the 2 different MALDI-TOF MSs in Dakar and Marseille. The 10 most common bacteria, representing 94.2% of all bacteria routinely identified in the laboratory in Dakar (Escherichia coli, Klebsiella pneumoniae, Streptococcus agalactiae, Acinetobacter baumannii, Pseudomonas aeruginosa, Staphylococcus aureus, Staphylococcus haemolyticus, Enterobacter cloacae, Enterococcus faecalis, and Staphylococcus epidermidis) were accurately identified with the MALDI-TOF MS in Dakar. The most frequent misidentification in Dakar was at the species level for Achromobacter xylosoxidans, which was inaccurately identified as Achromobacter denitrificans, and the bacteria absent from the database, such as Exiguobacterium aurientacum or Kytococcus schroeteri, could not be identified. A few difficulties were observed with MALDI-TOF MS for Bacillus sp. or oral streptococci. 16S rRNA sequencing identified a novel bacterium, “Necropsobacter massiliensis.” The robust identification of microorganisms by MALDI-TOF MS in Dakar and Marseille demonstrates that MALDI-TOF MS can be used as a first-line tool in clinical microbiology laboratories in tropical countries. PMID:26716681

Evaluation of free or anchored antimicrobial peptides as candidates for the prevention of orthopaedic device-related infections.

PubMed

D'Este, Francesca; Oro, Debora; Boix-Lemonche, Gerard; Tossi, Alessandro; Skerlavaj, Barbara

2017-10-01

The prevention of implant-associated infection, one the most feared complications in orthopaedic surgery, remains a major clinical challenge and urges development of effective methods to prevent bacterial colonization of implanted devices. Alpha-helical antimicrobial peptides (AMPs) may be promising candidates in this respect due to their potent and broad-spectrum antimicrobial activity, their low tendency to elicit resistance and possible retention of efficacy in the immobilized state. The aim of this study was to evaluate the potential of five different helical AMPs, the cathelicidins BMAP-27 and BMAP-28, their (1-18) fragments and the rationally designed, artificial P19(9/G7) peptide, for the prevention of orthopaedic implant infections. Peptides were effective at micromolar concentrations against 22 Staphylococcus and Streptococcus isolates from orthopaedic infections, while only BMAP-28 and to a lesser extent BMAP-27 were active against Enterococcus faecalis. Peptides in solution showed activities comparable to those of cefazolin and linezolid, on a molar basis, and also a variable capacity to neutralize bacterial lipopolysaccharide, while devoid of adverse effects on MG-63 osteoblast cells at concentrations corresponding to the MIC. The (1-18) BMAP fragments and P19(9/G7) were selected for further examination, based on better selectivity indices, and showed effectiveness in the presence of hyaluronic acid and in synovial fluid, while human serum affected their activity to variable extents, with BMAP-27(1-18) best retaining activity. This peptide was immobilized on streptavidin-resin beads and retained activity against reference Staphylococcus epidermidis and Staphylococcus aureus strains, with negligible toxicity towards osteoblasts, underlining its potential for the development of infection-resistant biomaterials for orthopaedic application. Copyright © 2017 European Peptide Society and John Wiley & Sons, Ltd. Copyright © 2017 European Peptide Society and John Wiley & Sons, Ltd.

Searching for a potential antibacterial lead structure against bacterial biofilms among new naphthoquinone compounds.

PubMed

Moreira, C S; Silva, A C J A; Novais, J S; Sá Figueiredo, A M; Ferreira, V F; da Rocha, D R; Castro, H C

2017-03-01

The aims of this study were to design, synthesize and to evaluate 2-hydroxy-3-phenylsulfanylmethyl-[1,4]-naphthoquinones against Gram-negative and Gram-positive bacterial strains, including methicillin-resistant Staphylococcus aureus (MRSA) and its biofilm, to probe for potential lead structures. Thirty-six new analogues were prepared with good yields using a simple, fast, operational three-procedure reaction and a thiol addition to an ο-quinone methide using microwave irradiation. All compounds were tested against Escherichia coli ATCC 25922, Pseudomonas aeruginosa ATCC 27853, Proteus mirabilis ATCC 15290, Serratia marcescens ATCC 14756, Klebsiella pneumoniae ATCC 4352, Enterobacter cloacae ATCC 23355, Enterococcus faecalis ATCC 29212, S. aureus ATCC 25923, Staphylococcus simulans ATCC 27851, Staphylococcus epidermidis ATCC 12228 and a hospital strain of MRSA. Their antibacterial activity was determined using the disc diffusion method, revealing the activity of 19 compounds, mainly against Gram-positive strains. Interestingly, the minimal inhibitory concentration ranges detected for the hit molecules (32-128 μg ml -1 ) were within Clinical and Laboratory Standards Institute levels. Promisingly, compound 15 affected the MRSA strain, with a reduction of up to 50% in biofilm formation, which is better than vancomycin as biofilm forms a barrier against the antibiotic that avoids its action. After probing 36 naphthoquinones for a potential antibacterial lead structure against the bacterial biofilm, we found that compound 15 should be explored further and also should be structurally modified in the near future to test against Gram-negative strains. Since vancomycin is one of the last treatment options currently available, and it is unable to inhibit biofilm, the research of new antimicrobials is urgent. In this context, 2-hydroxy-3-phenylsulfanylmethyl-[1,4]-naphthoquinones proved to be a promising lead structure against MRSA and bacterial biofilm. © 2016 The Society for Applied Microbiology.

Triterpenoids from Acacia ataxacantha DC: antimicrobial and antioxidant activities.

PubMed

Amoussa, Abdou Madjid O; Lagnika, Latifou; Bourjot, Mélanie; Vonthron-Senecheau, Cathérine; Sanni, Ambaliou

2016-08-12

Acacia ataxacantha is a medicinal specie used extensively in traditional medicine of Benin republic to treat infectious diseases. Our previous study showed interesting antibacterial and antifungal activities against six strains of bacteria and six strains of fungi. The aim of this study was to investigate the antimicrobial and antioxidant activities of compounds isolated from A. ataxacantha. Chromatographic and spectroscopic methods were used to isolate and identify three compounds (1-3) from the bark of A. ataxacantha. Phytochemical investigation of A. ataxacantha (Fabaceae) led to the isolation of three triterpenoids (1-3). The structure of isolated compounds was established by differents spectroscopic methods such as UV, (1)H NMR, (13)C NMR, 2D NMR and Mass. All isolated compounds were tested for antimicrobial activity using agar disc-diffusion and microdilution methods. The radical scavenging activity of isolated compounds was assessed using 2,2-diphenyl-1-picrylhydrazyl (DPPH) method. Phytochemical investigation led to the isolation and identification of lupeol (1), betulinic acid (2) and betulinic acid-3-trans-caffeate (3). Moderate antimicrobial activity was obtained with compound 3 against methicillin-resitant Staphylococcus aureus, Enterococcus feacalis and Pseudomonas aeruginosa with MIC value of 25 μg/ml and Staphylococcus aureus (MIC of 50 μg/ml). Compounds 3 was more active against Staphylococcus epidermidis and Candida albicans with a MIC value of 12.5 μg/ml in boths cases. Compounds 3 had also interesting antioxidant activity with an IC50 of 3.57 μg/ml compared to quercetin (1.04 μg/ml). The overall results of this study provide evidence that the compound 3, isolated from A. ataxacantha, exhibit antimicrobial activity against Gram-positive and Gram-negative bacteria and yeast, especially against C. albicans.

Susceptibility patterns and the role of extracellular DNA in Staphylococcus epidermidis biofilm resistance to physico-chemical stress exposure.

PubMed

Olwal, Charles Ochieng'; Ang'ienda, Paul Oyieng'; Onyango, David Miruka; Ochiel, Daniel Otieno

2018-05-02

Over 65% of human infections are ascribed to bacterial biofilms that are often highly resistant to antibiotics and host immunity. Staphylococcus epidermidis is the predominant cause of recurrent nosocomial and biofilm-related infections. However, the susceptibility patterns of S. epidermidis biofilms to physico-chemical stress induced by commonly recommended disinfectants [(heat, sodium chloride (NaCl), sodium hypochlorite (NaOCl) and hydrogen peroxide (H 2 O 2 )] in domestic and human healthcare settings remains largely unknown. Further, the molecular mechanisms of bacterial biofilms resistance to the physico-chemical stresses remain unclear. Growing evidence demonstrates that extracellular DNA (eDNA) protects bacterial biofilms against antibiotics. However, the role of eDNA as a potential mechanism underlying S. epidermidis biofilms resistance to physico-chemical stress exposure is yet to be understood. Therefore, this study aimed to evaluate the susceptibility patterns of and eDNA release by S. epidermidis biofilm and planktonic cells to physico-chemical stress exposure. S. epidermidis biofilms exposed to physico-chemical stress conditions commonly recommended for disinfection [heat (60 °C), 1.72 M NaCl, solution containing 150 μL of waterguard (0.178 M NaOCl) in 1 L of water or 1.77 M H 2 O 2 ] for 30 and 60 min exhibited lower log reductions of CFU/mL than the corresponding planktonic cells (p < 0.0001). The eDNA released by sub-lethal heat (50 °C)-treated S. epidermidis biofilm and planktonic cells was not statistically different (p = 0.8501). However, 50 °C-treated S. epidermidis biofilm cells released significantly increased eDNA than the untreated controls (p = 0.0098). The eDNA released by 0.8 M NaCl-treated S. epidermidis biofilm and planktonic cells was not significantly different (p = 0.9697). Conversely, 5 mM NaOCl-treated S. epidermidis biofilms exhibited significantly increased eDNA release than the corresponding planktonic cells (p = 0.0015). Further, the 50 μM H 2 O 2 -treated S. epidermidis biofilms released significantly more eDNA than the corresponding planktonic cells (p = 0.021). S. epidermidis biofilms were less susceptible to physico-chemical stress induced by the four commonly recommended disinfectants than the analogous planktonic cells. Further, S. epidermidis biofilms enhanced eDNA release in response to the sub-lethal heat and oxidative stress exposure than the corresponding planktonic cells suggesting a role of eDNA in biofilms resistance to the physico-chemical stresses.

Methicillin-resistant Staphylococcus sp. colonizing health care workers of a cancer hospital

PubMed Central

Costa, Dayane de Melo; Kipnis, André; Leão-Vasconcelos, Lara Stefânia Netto de Oliveira; Rocha-Vilefort, Larissa Oliveira; Telles, Sheila Araújo; André, Maria Cláudia Dantas Porfírio Borges; Tipple, Anaclara Ferreira Veiga; Lima, Ana Beatriz Mori; Ribeiro, Nádia Ferreira Gonçalves; Pereira, Mayara Regina; Prado-Palos, Marinésia Aparecida

2014-01-01

The aim of the study was to analyze epidemiological and microbiological aspects of oral colonization by methicillin-resistant Staphylococcus of health care workers in a cancer hospital. Interview and saliva sampling were performed with 149 health care workers. Antimicrobial resistance was determined by disk diffusion and minimum inhibitory concentration. Polymerase Chain Reaction, Internal Transcribed Spacer-Polymerase Chain Reaction and Pulsed Field Gel Electrophoresis were performed for genotypic characterization of methicillin-resistant Staphylococcus. Risk factors were determined by logistic regression. Methicillin-resistant Staphylococcus colonization prevalence was 19.5%, denture wearing (p = 0.03), habit of nail biting (p = 0.04) and preparation and administration of antimicrobial (p = 0.04) were risk factors identified. All methicillin-resistant Staphylococcus were S. epidermidis, 94.4% of them had mecA gene. Closely related and indistinguishable methicillin-resistant S. epidermidis were detected. These results highlight that HCWs which have contact with patient at high risk for developing infections were identified as colonized by MRSE in the oral cavity, reinforcing this cavity as a reservoir of these bacteria and the risk to themselves and patients safety, because these microorganisms may be spread by coughing and talking. PMID:25477910

Quality Control of Direct Molecular Diagnostics for Methicillin-Resistant Staphylococcus aureus▿

PubMed Central

van Belkum, Alex; Niesters, Hubert G. M.; MacKay, William G.; van Leeuwen, Willem B.

2007-01-01

Ten samples containing various amounts of methicillin-resistant Staphylococcus aureus (MRSA), methicillin-susceptible S. aureus, methicillin-resistant Staphylococcus epidermidis (MRSE), and combinations thereof were distributed to 51 laboratories for molecular diagnostics testing. Samples containing 102 to 103 MRSA cells were frequently reported to be negative. MRSE samples were scored as negative by all commercial tests but by only two out of three in-house tests. PMID:17581936

Staphylococcus muscae, a new species isolated from flies.

PubMed

Hájek, V; Ludwig, W; Schleifer, K H; Springer, N; Zitzelsberger, W; Kroppenstedt, R M; Kocur, M

1992-01-01

A new coagulase-negative species of the genus Staphylococcus, Staphylococcus muscae, is described on the basis of the results of a study of four strains that were isolated from flies. 16S rRNA sequences of the type strains of S. muscae, Staphylococcus schleiferi, and Staphylococcus sciuri were determined and used, together with the corresponding sequences of Staphylococcus aureus and Staphylococcus epidermidis, for a comparative analysis. The new species is characterized taxonomically; this species is differentiated from the other novobiocin-susceptible staphylococci by its physiological and biochemical activities, cell wall composition, and levels of genetic relatedness. The type strain of this species is strain MB4 (= CCM 4175).

Different sensitivity levels to norspermidine on biofilm formation in clinical and commensal Staphylococcus epidermidis strains.

PubMed

Ramón-Peréz, Miriam L; Díaz-Cedillo, Francisco; Contreras-Rodríguez, Araceli; Betanzos-Cabrera, Gabriel; Peralta, Humberto; Rodríguez-Martínez, Sandra; Cancino-Diaz, Mario E; Jan-Roblero, Janet; Cancino Diaz, Juan C

2015-02-01

Biofilm formation on medical and surgical devices is the main virulence factor of Staphylococcus epidermidis. A recent study has shown that norspermidine inhibits and disassembles the biofilm in the wild-type Bacillus subtilis NCBI3610 strain. In this study, the effect of norspermidine on S. epidermidis biofilm formation of clinical or commensal strains was tested. Biofilm producing strains of S. epidermidis were isolated from healthy skin (HS; n = 3), healthy conjunctiva (HC; n = 9) and ocular infection (OI; n = 19). All strains were treated with different concentrations of norspermidine, spermidine, putrescine, and cadaverine (1, 10, 25, 50 and 100 μM), and the biofilm formation was tested on microtiter plate. Besides, cell-free supernatants of S. epidermidis growth at 4 h and 40 h were analyzed by gas chromatography coupled to mass spectrometry (GC-MS) to detect norspermidine. Results showed that norspermidine at 25 μM and 100 μM prevented the biofilm formation in 45.16% (14/31) and 16.13% (5/31), respectively; only in one isolate from OI, norspermidine did not have effect. Other polyamines as spermidine, putrescine and cadaverine did not have effect on the biofilm formation of the strains tested. Norspermidine was also capable to disassemble a biofilm already formed. Norspermidine was detected in the 40 h cell-free supernatant of S. epidermidis by GC-MS. Norspermidine inhibited the biofilm development of S. epidermidis on the surface of contact lens. In this work, it was demonstrated that S. epidermidis produces and releases norspermidine causing an inhibitory effect on biofilm formation. Moreover, this is the first time showing that clinical S. epidermidis strains have different sensitivity to norspermidine, which suggest that the composition and structure of the biofilms is varied. We propose that norspermidine could potentially be used in the pre-treating of medical and surgical devices to inhibit the biofilm formation. Copyright © 2015 Elsevier Ltd. All rights reserved.

Using Enzymes to Improve Antibiotic Effectiveness on "Staphylococcus Epidermidis" Biofilm Removal

ERIC Educational Resources Information Center

Candal, Carmen

2012-01-01

The effectiveness of five different enzymes as treatments against Staphylococcus biofilm growth was measured in the presence of antibiotics and alone. Protease was the least effective enzyme in biofilm removal with all antibiotics, and pectinase was the most effective with dicloxacillin and clindamycin. Also, dicloxacillin was the most effective…

Microbiological characteristics of "androlla", a Spanish traditional pork sausage.

PubMed

García Fontán, María C; Lorenzo, José M; Parada, Ana; Franco, Inmaculada; Carballo, Javier

2007-02-01

Counts of total aerobic mesophilic microflora, lactic acid bacteria, salt-tolerant microflora, Enterobacteriaceae, enterococci, moulds and yeasts, and staphylococci, and some physico-chemical parameters (total solids, NaCl and nitrate contents and pH and aw values) were determined in 20 units of "androlla", a traditional dry-fermented sausage made in the NW of Spain. In general, high counts of all the investigated microbial groups were observed, with average values of 8.99 +/- 0.46 log cfu/g for the total aerobic mesophilic microflora, 9.11 +/- 0.16 log cfu/g for the lactic acid bacteria, 6.87 +/- 0.68 log cfu/g for the salt-tolerant microflora, 2.80+/-1.85 log cfu/g for the Enterobacteriaceae, 3.25 +/- 1.86 log cfu/g for the enterococci, 4.30 +/- 1.73 log cfu/g for the moulds and yeasts, and 3.62 +/- 0.60 log cfu/g for the staphylococci. From MRS agar, SPC agar + 7.5% NaCl, VRBG agar, and KAA agar, 10 colonies were randomly taken from each androlla unit and from each culture medium. A total of 200 strains per culture medium were then identified using the classical methods. Among the isolates from MRS agar, Lactobacillus sakei predominated, followed by Lactobacillus curvatus, Lactobacillus alimentarius and Lactobacillus plantarum. Of the 200 isolates obtained from SPC agar + 7.5% NaCl, only 56 strains belonged to the Staphylococcaceae or Micrococcaceae families. Among the Staphylococcaceae, Staphylococcus xylosus was the main species, followed by Staph. epidermidis; Staph. equorum, Staph. capitis and Staph. saprophyticus were isolated in very low proportions. Among the Micrococcaceae, Micrococcus luteus predominated, followed by Micrococcus lylae, Kocuria varians and Kocuria kristinae. Of the 150 isolates obtained from VRBG agar, Hafnia alvei was the main species, followed by Serratia liquefaciens and Enterobacter amnigenus; six isolates were identified as Salmonella. Among the 190 isolates obtained from KAA agar, 122 were considered enterococci; 20 isolates were identified as Enterococcus faecium, one as Enterococcus faecalis and 101 as Enterococcus inter faecalis-faecium.

Introducing Urtica dioica, A Native Plant of Khuzestan, As an Antibacterial Medicinal Plant.

PubMed

Motamedi, Hossein; Seyyednejad, Seyyed Mansour; Bakhtiari, Ameneh; Vafaei, Mozhan

2014-11-01

Urtica dioica is a flowering plant with long history of use in folk medicine and as a food source. This study examined in vitro antibacterial potential of alcoholic extracts of U. dioica. Hydroalcoholic extracts from aerial parts were prepared using aqueous solution of ethanol and methanol and their inhibitory effects against clinical isolates was examined by disc diffusion method at different doses. Minimum inhibitory concentrations (MIC) and minimum bactericidal concentration (MBC) indexes were also investigated. The scanning electron microscopy (SEM) analysis was also performed to find structural changes of affected bacteria consequent to exposing with extracts. Both extracts were active against Bacillus cereus, Staphylococcus aureus, Staphylococcus epidermidis, and Escherichia coli with respectively 16, 10, 18, and 14 mm (methanolic) and 11, 9, 17, and 16 mm (ethanolic) inhibition zone. The MIC of ethanolic extract against S. epidermidis and E. coli was respectively 10 and 40 mg/mL. The MIC of methanolic extract against S. aureus and S. epidermidis was 40 and 10 mg/mL, respectively. The MBC was found only for S. epidermidis (20 mg/mL). In SEM analysis the round shape of S. epidermidis was changed and irregular shapes were appeared, which suggest that the main target of these extracts was cell wall. Extracts of U. dioica showed significant antibacterial effect against some clinically important pathogenic bacteria. Based on the obtained results it can be concluded that U. dioica is useful as antibacterial and bactericidal agent in treating infectious diseases.

pH value promotes growth of Staphylococcus epidermidis in platelet concentrates.

PubMed

Störmer, Melanie; Kleesiek, Knut; Dreier, Jens

2008-05-01

The platelet (PLT) storage lesion is characterized metabolically by a pH value associated with lactic acid generation. PLT storage conditions support the growth of Staphylococcus epidermidis, the most common organism implicated in bacterial contamination of PLT concentrates (PCs). Here, different factors that influence bacterial growth in PCs are discussed and the relation between pH values of PCs and citrate plasma (CP) is studied, with emphasis on bacterial proliferation. The PLT lesion with regard to pH decrease and lactic acid production was monitored during storage and correlated to bacterial proliferation properties. A total of 115 coagulase-negative staphylococci, especially S. epidermidis isolates, were characterized for their proliferation in different blood components (CP, buffy coat-derived, and apheresis PCs). Furthermore, the influence of donor-specific, product-specific, species-specific, and strain-specific factors on bacterial proliferation was investigated. PCs showed a lower pH value in comparison to plasma during storage. Bacterial proliferation in PCs and the failure to grow in CP were determined with all organisms tested. No correlation to donor-specific, species-specific, or strain-specific factors was observed. Lowering the pH of CP resulted in bacterial proliferation, whereas a pH increase in the PC unit inhibited the proliferation of S. epidermidis. With emphasis on bacterial proliferation, the significant difference between PC and CP is the presence of metabolizing PLTs. The pH values of stored PLTs, but not those of stored plasma, support the growth of S. epidermidis.

Mutations in the quinolone resistance determining region in Staphylococcus epidermidis recovered from conjunctiva and their association with susceptibility to various fluoroquinolones.

PubMed

Yamada, M; Yoshida, J; Hatou, S; Yoshida, T; Minagawa, Y

2008-06-01

Staphylococcus epidermidis is one of the prominent pathogens in ocular infection. The prevalence of mutations in the quinolone resistance determining region (QRDR) area in S epidermidis isolated from the ocular surface and its association with fluoroquinolone resistance has not been fully elucidated. Mutations in the QRDR of gyrA, gyrB, parC, and parE genes of 138 isolates of S epidermidis recovered from the human conjunctival flora were analysed. The minimal inhibitory concentrations (MICs) of four fluoroquinolones (levofloxacin, gatifloxacin, moxifloxacin and tosufloxacin) against these isolates were also determined using agar dilution methods. The MIC(90) values of levofloxacin, gatifloxacin, moxifloxacin and tosufloxacin were 3.13, 1.56, 0.78 and 3.13 microg/ml, respectively. The MIC values of all fluoroquinolones showed a bimodal distribution (susceptible strain and less susceptible strain). Mutations with amino acid substitution in the QRDR were present in 70 (50.7%) isolates. 19 different combinations of mutations were detected: 3 isolates (2.2%) had four mutations, 8 (5.8%) had three mutations, 43 (31.2%) had double mutations and 16 (11.6%) had single mutations. Isolates with mutations in the QRDR of both gyrA and parC (n = 53) were less susceptible to fluoroquinolones. The present findings show that approximately half the S epidermidis isolates from the normal human conjunctiva have mutation(s) in the QRDR. The presence of mutations in both gyrA and parC is strongly associated with reduced susceptibility to fluoroquinolones.

Inhibition of Staphylococcus epidermidis Biofilm Formation by Traditional Thai Herbal Recipes Used for Wound Treatment

PubMed Central

Chusri, S.; Sompetch, K.; Mukdee, S.; Jansrisewangwong, S.; Srichai, T.; Maneenoon, K.; Limsuwan, S.; Voravuthikunchai, S. P.

2012-01-01

Development of biofilm is a key mechanism involved in Staphylococcus epidermidis virulence during device-associated infections. We aimed to investigate antibiofilm formation and mature biofilm eradication ability of ethanol and water extracts of Thai traditional herbal recipes including THR-SK004, THR-SK010, and THR-SK011 against S. epidermidis. A biofilm forming reference strain, S. epidermidis ATCC 35984 was employed as a model for searching anti-biofilm agents by MTT reduction assay. The results revealed that the ethanol extract of THR-SK004 (THR-SK004E) could inhibit the formation of S. epidermidis biofilm on polystyrene surfaces. Furthermore, treatments with the extract efficiently inhibit the biofilm formation of the pathogen on glass surfaces determined by scanning electron microscopy and crystal violet staining. In addition, THR-SK010 ethanol extract (THR-SK010E; 0.63–5 μg/mL) could decrease 30 to 40% of the biofilm development. Almost 90% of a 7-day-old staphylococcal biofilm was destroyed after treatment with THR-SK004E (250 and 500 μg/mL) and THR-SK010E (10 and 20 μg/mL) for 24 h. Therefore, our results clearly demonstrated THR-SK004E could prevent the staphylococcal biofilm development, whereas both THR-SK004E and THR-SK010E possessed remarkable eradication ability on the mature staphylococcal biofilm. PMID:22919409

Exposure to chorioamnionitis alters the monocyte transcriptional response to the neonatal pathogen Staphylococcus epidermidis.

PubMed

de Jong, Emma; Hancock, David G; Wells, Christine; Richmond, Peter; Simmer, Karen; Burgner, David; Strunk, Tobias; Currie, Andrew J

2018-03-13

Preterm infants are uniquely susceptible to late-onset sepsis that is frequently caused by the skin commensal Staphylococcus epidermidis. Innate immune responses, particularly from monocytes, are a key protective mechanism. Impaired cytokine production by preterm infant monocytes is well described, but few studies have comprehensively assessed the corresponding monocyte transcriptional response. Innate immune responses in preterm infants may be modulated by inflammation such as prenatal exposure to histologic chorioamnionitis which complicates 40-70% of preterm pregnancies. Chorioamnionitis alters the risk of late-onset sepsis, but its effect on monocyte function is largely unknown. Here, we aimed to determine the impact of exposure to chorioamnionitis on the proportions and phenotype of cord blood monocytes using flow cytometry, as well as their transcriptional response to live S. epidermidis. RNA-seq was performed on purified cord blood monocytes from very preterm infants (<32 weeks gestation, with and without chorioamnionitis-exposure) and term infants (37-40 weeks), pre- and postchallenge with live S. epidermidis. Preterm monocytes from infants without chorioamnionitis-exposure did not exhibit an intrinsically deficient transcriptional response to S. epidermidis compared to term infants. In contrast, chorioamnionitis-exposure was associated with hypo-responsive transcriptional phenotype regarding a subset of genes involved in antigen presentation and adaptive immunity. Overall, our findings suggest that prenatal exposure to inflammation may alter the risk of sepsis in preterm infants partly by modulation of monocyte responses to pathogens. © 2018 Australasian Society for Immunology Inc.

Review and phylogenetic analysis of qac genes that reduce susceptibility to quaternary ammonium compounds in Staphylococcus species

PubMed Central

Ussery, David; Nielsen, Lene N.; Ingmer, Hanne

2015-01-01

The qac genes of Staphylococcus species encode multidrug efflux pumps: membrane proteins that export toxic molecules and thus increase tolerance to a variety of compounds such as disinfecting agents, including quaternary ammonium compounds (for which they are named), intercalating dyes and some antibiotics. In Stapylococcus species, six different plasmid-encoded Qac efflux pumps have been described, and they belong to two major protein families. QacA and QacB are members of the Major Facilitator Superfamily, while QacC, QacG, QacH, and QacJ all belong to the Small Multidrug Resistance (SMR) family. Not all SMR proteins are called Qac and the reverse is also true, which has caused confusion in the literature and in gene annotations. The discovery of qac genes and their presence in various staphylococcal populations is briefly reviewed. A sequence comparison revealed that some of the PCR primers described in the literature for qac detection may miss particular qac genes due to lack of DNA conservation. Despite their resemblance in substrate specificity, the Qac proteins belonging to the two protein families have little in common. QacA and QacB are highly conserved in Staphylococcus species, while qacA was also detected in Enterococcus faecalis, suggesting that these plasmid-born genes have spread across bacterial genera. Nevertheless, these qacA and qacB genes are quite dissimilar to their closest homologues in other organisms. In contrast, SMR-type Qac proteins display considerable sequence variation, despite their short length, even within the Staphylococcus genus. Phylogenetic analysis of these genes identified similarity to a large number of other SMR members, found in staphylococci as well as in other genera. A number of phylogenetic trees of SMR Qac proteins are presented here, starting with genes present in S. aureus and S. epidermidis, and extending this to related genes found in other species of this genus, and finally to genes found in other genera. PMID:25883793

Review and phylogenetic analysis of qac genes that reduce susceptibility to quaternary ammonium compounds in Staphylococcus species.

PubMed

Wassenaar, Trudy M; Ussery, David; Nielsen, Lene N; Ingmer, Hanne

2015-03-01

The qac genes of Staphylococcus species encode multidrug efflux pumps: membrane proteins that export toxic molecules and thus increase tolerance to a variety of compounds such as disinfecting agents, including quaternary ammonium compounds (for which they are named), intercalating dyes and some antibiotics. In Stapylococcus species, six different plasmid-encoded Qac efflux pumps have been described, and they belong to two major protein families. QacA and QacB are members of the Major Facilitator Superfamily, while QacC, QacG, QacH, and QacJ all belong to the Small Multidrug Resistance (SMR) family. Not all SMR proteins are called Qac and the reverse is also true, which has caused confusion in the literature and in gene annotations. The discovery of qac genes and their presence in various staphylococcal populations is briefly reviewed. A sequence comparison revealed that some of the PCR primers described in the literature for qac detection may miss particular qac genes due to lack of DNA conservation. Despite their resemblance in substrate specificity, the Qac proteins belonging to the two protein families have little in common. QacA and QacB are highly conserved in Staphylococcus species, while qacA was also detected in Enterococcus faecalis, suggesting that these plasmid-born genes have spread across bacterial genera. Nevertheless, these qacA and qacB genes are quite dissimilar to their closest homologues in other organisms. In contrast, SMR-type Qac proteins display considerable sequence variation, despite their short length, even within the Staphylococcus genus. Phylogenetic analysis of these genes identified similarity to a large number of other SMR members, found in staphylococci as well as in other genera. A number of phylogenetic trees of SMR Qac proteins are presented here, starting with genes present in S. aureus and S. epidermidis, and extending this to related genes found in other species of this genus, and finally to genes found in other genera.

[Investigation of the situation of vaginal microflora in healthy women population].

PubMed

Ji, Fang; Zhang, Ning; Di, Wen; Liao, Qin-ping; Wang, Wen; Zhao, Xiao-ming; Sun, Yun; Liu, Zhao-hui

2009-01-01

To assess the distribution of vaginal microflora in healthy women and investigate their cognition of lower reproductive tract infection-related knowledge as well as personal hygiene habits and character of behavior in seeking medical treatment. Total of 1660 healthy women who had physical check-ups at the Medical Center of Renji Hospital were selected and received gynecologic examination, as well as routine examination, pH examination and bacterial culture of the vaginal discharge. In addition, 860 of them were randomly selected for questionnaire survey, in which reproductive tract infection -related knowledge and personal hygiene habits as well as behavior in seeking medical treatment were involved. Among the 1660 censused women, vaginal average pH was 4. 16 +/- 0.21. The positive rate of Candida in vaginal discharge routine examination was 3.86% (64/1660), which was lower than that in aerobes culture 7.71% (128/1660). Candida albicans was the most populous species 78.9% (101/128), followed by 7.8% (10/128) and 7.0% (9/128) for the Candida glabrata and Candida krusei respectively. The most populous species of vaginal microflora were hemolytic streptococcus A (63.80%, 1059/1660), Staphylococcus epidermidis (14.28%, 237/1660), and Enterococcus faecalis (D) group (11.44%, 190/1660). The questionnaire survey showed that 88.4% (760/860) of 860 women took active treatment when feeling unwell, 92.1% (792/860) of them had good hygiene practices, and only 21.2% (182/860) had the habit of vaginal douching. In addition, 50.0% (430/860) of them had the desire to obtain reproductive health knowledge through out-patient consultation. Vulvovaginal Candida disease ranks the first in all types of vaginitis, among which, Candida albicans is the most populous species followed by the Candida glabrata and Candida krusei. Hemolytic streptococcus A and Staphylococcus epidermidis are the most common species of vaginal microflora in healthy women. The censused women have high awareness of reproductive health care and pay much attention to common gynecologic diseases such as lower reproductive tract infection. Nevertheless, we should strengthen the public education of reproductive health-related knowledge.

Efficacy of a surfactant-based wound dressing on biofilm control.

PubMed

Percival, Steven L; Mayer, Dieter; Salisbury, Anne-Marie

2017-09-01

The aim of this study was to evaluate the efficacy of both a nonantimicrobial and antimicrobial (1% silver sulfadiazine-SSD) surfactant-based wound dressing in the control of Pseudomonas aeruginosa, Enterococcus sp, Staphylococcus epidermidis, Staphylococcus aureus, and methicillin-resistant S. aureus (MRSA) biofilms. Anti-biofilm efficacy was evaluated in numerous adapted American Standards for Testing and Materials (ASTM) standard biofilm models and other bespoke biofilm models. The ASTM standard models employed included the Minimum biofilm eradication concentration (MBEC) biofilm model (ASTM E2799) and the Centers for Disease Control (CDC) biofilm reactor model (ASTM 2871). Such bespoke biofilm models included the filter biofilm model and the chamberslide biofilm model. Results showed complete kill of microorganisms within a biofilm using the antimicrobial surfactant-based wound dressing. Interestingly, the nonantimicrobial surfactant-based dressing could disrupt existing biofilms by causing biofilm detachment. Prior to biofilm detachment, we demonstrated, using confocal laser scanning microscopy (CLSM), the dispersive effect of the nonantimicrobial surfactant-based wound dressing on the biofilm within 10 minutes of treatment. Furthermore, the non-antimicrobial surfactant-based wound dressing caused an increase in microbial flocculation/aggregation, important for microbial concentration. In conclusion, this nonantimicrobial surfactant-based wound dressing leads to the effective detachment and dispersion of in vitro biofilms. The use of surfactant-based wound dressings in a clinical setting may help to disrupt existing biofilm from wound tissue and may increase the action of antimicrobial treatment. © 2017 by the Wound Healing Society.

Synergistic effect of Carum copticum and Mentha piperita essential oils with ciprofloxacin, vancomycin, and gentamicin on Gram-negative and Gram-positive bacteria

PubMed Central

Talei, Gholam-Reza; Mohammadi, Mohsen; Bahmani, Mahmoud; Kopaei, Mahmoud Rafieian

2017-01-01

Background: Infectious diseases have always been an important health issue in human communities. In the recent years, much research has been conducted on antimicrobial effects of nature-based compounds because of increased prevalence of antibiotic resistance. The present study was conducted to investigate synergistic effect of Carum copticum and Mentha piperita essential oils with ciprofloxacin, vancomycin, and gentamicin on Gram-negative and Gram-positive bacteria. Materials and Methods: In this experimental study, the synergistic effects of C. copticum and M. piperita essential oils with antibiotics on Staphylococcus aureus (ATCC 25923), Enterococcus faecalis (ATCC 29212), Escherichia coli (ATCC 8739), Pseudomonas aeruginosa (ATCC 9027), Staphylococcus epidermidis (ATCC 14990), and Listeria monocytogenes (ATCC 7644) were studied according to broth microdilution and the MIC and fractional inhibitory concentration (FIC) of these two essential oils determined. Results: C. copticum essential oil at 30 μg/ml could inhibit S. aureus, and in combination with vancomycin, decreased MIC from 0.5 to 0.12 μg/ml. Moreover, the FIC was derived 0.24 μg/ml which represents a potent synergistic effect with vancomycin against S. aureus growth. C. copticum essential oil alone or combined with other antibiotics is effective in treating bacterial infections. Conclusions: In addition, C. copticum essential oil can strengthen the activities of certain antibiotics, which makes it possible to use this essential oil, especially in drug resistance or to lower dosage or toxicity of the drugs. PMID:28929050

Potential of berberine to enhance antimicrobial activity of commonly used antibiotics for dairy cow mastitis caused by multiple drug-resistant Staphylococcus epidermidis infection.

PubMed

Zhou, X; Yang, C; Li, Y; Liu, X; Wang, Y

2015-08-19

Berberine is a plant alkaloid with antimicrobial activity against a variety of microorganisms. In this study, the antimicrobial properties of berberine against multi-drug resistant field isolates of Staphylococcus epidermidis were investigated using berberine alone or in combination with a commonly used antibiotics in veterinary clinics, including penicillin, lincomycin, and amoxicillin. The results indicated that the minimum inhibitory concentrations of berberine, penicillin, lincomycin, and amoxicillin against field S. epidermidis isolates were 2-512, 0.8-213, 0.4-1024, and 0.4-256 mg/mL, respectively. Furthermore, the synergistic effects of antimicrobial activity against these multi-drug resistant isolates were observed when the berberine was combined with penicillin, lincomycin, or amoxicillin; no antagonistic effect of the combination was detected in any of the clinical isolates. These observations were further confirmed using a time-killing assay, in which a combination of 2 agents yielded a greater than 2.03-2.44 log10 decrease in colony-forming unit/mL compared with each agent alone. These findings suggest that berberine is a promising compound for preventing and treating multi-drug resistant S. epidermidis infected mastitis in dairy cows either alone or in combination with other commonly used antibiotics, such as penicillin, lincomycin, and amoxicillin.

Hypervariability of biofilm formation and oxacillin resistance in a Staphylococcus epidermidis strain causing persistent severe infection in an immunocompromised patient.

PubMed

Weisser, Maja; Schoenfelder, Sonja M K; Orasch, Christina; Arber, Caroline; Gratwohl, Alois; Frei, Reno; Eckart, Martin; Flückiger, Ursula; Ziebuhr, Wilma

2010-07-01

We report on a leukemic patient who suffered from a persistent, generalized, and eventually fatal Staphylococcus epidermidis infection during prolonged aplasia. Over a 6-week period, we isolated a genetically and phenotypically unstable S. epidermidis strain related to an epidemic clone associated with hospital infections worldwide. Strikingly, the strain showed a remarkable degree of variability, with evidence of selection and increasing predominance of biofilm-producing and oxacillin-resistant variants over time. Thus, in the early stages of the infection, the strain was found to generate subpopulations which had spontaneously lost the biofilm-mediating ica locus along with the oxacillin resistance-conferring mecA gene. These deletion mutants were obviously outcompeted by the ica- and mecA-positive wild-type genotype, with the selection and predominance of strongly biofilm-forming and oxacillin-resistant variants in the later stages of the infection. Also, a switch from protein- to polysaccharide intercellular adhesin/poly-N-acetylglucosamine (PIA/PNAG)-mediated-biofilm production was detected among ica-positive variants in the course of the infection. The data highlight the impact of distinct S. epidermidis clonal lineages as serious nosocomial pathogens that, through the generation and selection of highly pathogenic variants, may critically determine disease progression and outcome.

Incorporation of staphylococci into titanium-grown biofilms: an in vitro "submucosal" biofilm model for peri-implantitis.

PubMed

Thurnheer, Thomas; Belibasakis, Georgios N

2016-07-01

Staphylococcus spp. are postulated to play a role in peri-implantitis. This study aimed to develop a "submucosal" in vitro biofilm model, by integrating two staphylococci into its composition. The standard "subgingival" biofilm contained Actinomyces oris, Fusobacterium nucleatum, Streptococcus oralis, Veillonella dispar, Campylobacter rectus, Prevotella intermedia, Streptococcus anginosus, Porphyromonas gingivalis, Tannerella forsythia and Treponema denticola, and was further supplemented with Staphyoccous aureus and/or Staphylococcus epidermidis. Biofilms were grown anaerobically on hydroxyapatite or titanium discs and harvested after 64 h for real-time polymerase chain reaction, to determine their composition. Confocal laser scanning microscopy and fluorescence in situ hybridization were used for identifying the two staphylococci within the biofilm. Both staphylococci established within the biofilms when added separately. However, when added together, only S. aureus grew in high numbers, whereas S. epidermidis was reduced almost to the detection limit. Compared to the standard subgingival biofilm, addition of the two staphylococci had no impact on the qualitative or quantitative composition of the biofilm. When grown individually in the biofilm, S. epidermidis and S. aureus formed small distinctive clusters and it was confirmed that S. epidermidis was not able to grow in presence of S. aureus. Staphyoccous aureus and S. epidermidis can be individually integrated into an oral biofilm grown on titanium, hence establishing a "submucosal" biofilm model for peri-implantitis. This model also revealed that S. aureus outcompetes S. epidermidis when grown together in the biofilm, which may explain the more frequent association of the former with peri-implantitis. © 2015 The Authors. Clinical Oral Implants Research Published by John Wiley & Sons Ltd.

In Vitro Studies of Pharmacodynamic Properties of Vancomycin against Staphylococcus aureus and Staphylococcus epidermidis

PubMed Central

Löwdin, E.; Odenholt, I.; Cars, O.

1998-01-01

The bactericidal activities of vancomycin against two reference strains and two clinical isolates of Staphylococcus aureus and Staphylococcus epidermidis were studied with five different concentrations ranging from 2× to 64× the MIC. The decrease in the numbers of CFU at 24 h was at least 3 log10 CFU/ml for all strains. No concentration-dependent killing was observed. The postantibiotic effect (PAE) was determined by obtaining viable counts for two of the reference strains, and the viable counts varied markedly: 1.2 h for S. aureus and 6.0 h for S. epidermidis. The determinations of the PAE, the postantibiotic sub-MIC effect (PA SME), and the sub-MIC effect (SME) for all strains were done with BioScreen C, a computerized incubator for bacteria. The PA SMEs were longer than the SMEs for all strains tested. A newly developed in vitro kinetic model was used to expose the bacteria to continuously decreasing concentrations of vancomycin. A filter prevented the loss of bacteria during the experiments. One reference strain each of S. aureus and S. epidermidis and two clinical isolates of S. aureus were exposed to an initial concentration of 10× the MIC of vancomycin with two different half-lives (t1/2s): 1 or 5 h. The post-MIC effect (PME) was calculated as the difference in time for the bacteria to grow 1 log10 CFU/ml from the numbers of CFU obtained at the time when the MIC was reached and the corresponding time for an unexposed control culture. The difference in PME between the strains was not as pronounced as that for the PAE. Furthermore, the PME was shorter when a t1/2 of 5 h (approximate terminal t1/2 in humans) was used. The PMEs at t1/2s of 1 and 5 h were 6.5 and 3.6 h, respectively, for S. aureus. The corresponding figures for S. epidermidis were 10.3 and less than 6 h. The shorter PMEs achieved with a t1/2 of 5 h and the lack of concentration-dependent killing indicate that the time above the MIC is the parameter most important for the efficacy of vancomycin. PMID:9756787

Staphylococcus aureus and Staphylococcus epidermidis strain diversity underlying pediatric atopic dermatitis.

PubMed

Byrd, Allyson L; Deming, Clay; Cassidy, Sara K B; Harrison, Oliver J; Ng, Weng-Ian; Conlan, Sean; Belkaid, Yasmine; Segre, Julia A; Kong, Heidi H

2017-07-05

The heterogeneous course, severity, and treatment responses among patients with atopic dermatitis (AD; eczema) highlight the complexity of this multifactorial disease. Prior studies have used traditional typing methods on cultivated isolates or sequenced a bacterial marker gene to study the skin microbial communities of AD patients. Shotgun metagenomic sequence analysis provides much greater resolution, elucidating multiple levels of microbial community assembly ranging from kingdom to species and strain-level diversification. We analyzed microbial temporal dynamics from a cohort of pediatric AD patients sampled throughout the disease course. Species-level investigation of AD flares showed greater Staphylococcus aureus predominance in patients with more severe disease and Staphylococcus epidermidis predominance in patients with less severe disease. At the strain level, metagenomic sequencing analyses demonstrated clonal S. aureus strains in more severe patients and heterogeneous S. epidermidis strain communities in all patients. To investigate strain-level biological effects of S. aureus , we topically colonized mice with human strains isolated from AD patients and controls. This cutaneous colonization model demonstrated S. aureus strain-specific differences in eliciting skin inflammation and immune signatures characteristic of AD patients. Specifically, S. aureus isolates from AD patients with more severe flares induced epidermal thickening and expansion of cutaneous T helper 2 (T H 2) and T H 17 cells. Integrating high-resolution sequencing, culturing, and animal models demonstrated how functional differences of staphylococcal strains may contribute to the complexity of AD disease. Copyright © 2017 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works.

Identification, Characterization, and Recombinant Expression of Epidermicin NI01, a Novel Unmodified Bacteriocin Produced by Staphylococcus epidermidis That Displays Potent Activity against Staphylococci

PubMed Central

Sandiford, Stephanie

2012-01-01

We describe the discovery, purification, characterization, and expression of an antimicrobial peptide, epidermicin NI01, which is an unmodified bacteriocin produced by Staphylococcus epidermidis strain 224. It is a highly cationic, hydrophobic, plasmid-encoded peptide that exhibits potent antimicrobial activity toward a wide range of pathogenic Gram-positive bacteria including methicillin-resistant Staphylococcus aureus (MRSA), enterococci, and biofilm-forming S. epidermidis strains. Purification of the peptide was achieved using a combination of hydrophobic interaction, cation exchange, and high-performance liquid chromatography (HPLC). Matrix-assisted laser desorption ionization–time of flight (MALDI-TOF) analysis yielded a molecular mass of 6,074 Da, and partial sequence data of the peptide were elucidated using a combination of tandem mass spectrometry (MS/MS) and de novo sequencing. The draft genome sequence of the producing strain was obtained using 454 pyrosequencing technology, thus enabling the identification of the structural gene using the de novo peptide sequence data previously obtained. Epidermicin NI01 contains 51 residues with four tryptophan and nine lysine residues, and the sequence showed approximately 50% identity to peptides lacticin Z, lacticin Q, and aureocin A53, all of which belong to a new family of unmodified type II-like bacteriocins. The peptide is active in the nanomolar range against S. epidermidis, MRSA isolates, and vancomycin-resistant enterococci. Other unique features displayed by epidermicin include a high degree of protease stability and the ability to retain antimicrobial activity over a pH range of 2 to 10, and exposure to the peptide does not result in development of resistance in susceptible isolates. In this study we also show the structural gene alone can be cloned into Escherichia coli strain BL21(DE3), and expression yields active peptide. PMID:22155816

Staphylococcus epidermidis Biofilms: Functional Molecules, Relation to Virulence, and Vaccine Potential

NASA Astrophysics Data System (ADS)

Mack, Dietrich; Davies, Angharad P.; Harris, Llinos G.; Knobloch, Johannes K. M.; Rohde, Holger

Medical device-associated infections, most frequently caused by Staphylococcus epidermidis and Staphylococcus aureus, are of increasing importance in modern medicine. The formation of adherent, multilayered bacterial biofilms is crucial in the pathogenesis of these infections. Polysaccharide intercellular adhesin (PIA), a homoglycan of β-1,6-linked 2-acetamido-2-deoxy-d-glucopyranosyl residues, of which about 15% are non-N-acetylated, is central to biofilm accumulation in staphylococci. It transpires that polysaccharides - structurally very similar to PIA - are also key to biofilm formation in a number of other organisms including the important human pathogens Escherichia coli, Aggregatibacter (Actinobacillus) actinomycetemcomitans, Yersinia pestis, and Bordetella spp. Apparently, synthesis of PIA and related polysaccharides is a general feature important for biofilm formation in diverse bacterial genera. Current knowledge about the structure and biosynthesis of PIA and related polysaccharides is reviewed. Additionally, information on their role in pathogenesis of biomaterial-related and other type of infections and the potential use of PIA and related compounds for prevention of infection is evaluated.

Analyzing the antibacterial effects of food ingredients: model experiments with allicin and garlic extracts on biofilm formation and viability of Staphylococcus epidermidis

PubMed Central

Wu, Xueqing; Santos, Regiane R; Fink-Gremmels, Johanna

2015-01-01

To demonstrate different effects of garlic extracts and their main antibiotic substance allicin, as a template for investigations on the antibacterial activity of food ingredients. Staphylococcus epidermidis ATCC 12228 and the isogenic biofilm-forming strain ATCC 35984 were used to compare the activity of allicin against planktonic bacteria and bacterial biofilms. The minimal inhibitory concentration (MIC) and the minimum biofilm inhibitory concentration (MBIC) for pure allicin were identical and reached at a concentration of 12.5 μg/mL. MBICs for standardized garlic extracts were significantly lower, with 1.56 and 0.78 μg/mL allicin for garlic water and ethanol extract, respectively. Biofilm density was impaired significantly at a concentration of 0.78 μg/mL allicin. Viability staining followed by confocal laser scanning microscopy showed, however, a 100% bactericidal effect on biofilm-embedded bacteria at a concentration of 3.13 μg/mL allicin. qRT-PCR analysis provided no convincing evidence for specific effects of allicin on biofilm-associated genes. Extracts of fresh garlic are more potent inhibitors of Staphylococcus epidermidis biofilms than pure allicin, but allicin exerts a unique bactericidal effect on biofilm-embedded bacteria. The current experimental protocol has proven to be a valid approach to characterize the antimicrobial activity of traditional food ingredients. PMID:25838894

Formation of harmful compounds in biotransformation of lilial by microorganisms isolated from human skin.

PubMed

Esmaeili, Akbar; Afshari, Shima; Esmaeili, Davood

2015-01-01

The biotransformation of lilial results in an acid that is used in the dairy industry, in perfumery, as an intermediate in the manufacture of pharmaceuticals and cosmetics, and as a food additive for enhancing taste. This study investigates the biotransformation of lilial by Staphylococcus aureus and Staphylococcus epidermidis, two bacterial species isolated from human skin. Both species of Staphylococcus were isolated in samples taken from the skin of individuals living in a rural area of Iran. The pH of the culture medium was optimized, and after culturing the microorganisms, the bacteria were added to a flask containing a nutrient broth and incubated for several hours. The flasks of bacteria were combined with lilial, and various biochemical tests and diagnostics were performed, including Fourier transform infrared spectroscopy (FT-IR), ultraviolet-visible spectrophotometry (UV-Vis), and gas chromatography-mass spectroscopy (GC-MS). The S. aureus produced isobutyric acid (2-methylpropanoic acid) after 72 h (71% of the total products yielded during biotransformation), whereas the S. epidermidis produced terpenoid alcoholic media after 24 h (90% of total products obtained). The results obtained indicate that biotransformation of lilial by S. aureus is more desirable than by S. epidermidis due to the highly efficient production of a single product. Bourgeonal and liliol were two toxic compounds produced during biotransformation, which indicates that the use of lilial in cosmetics can be harmful to the skin.

New perspectives for natural antimicrobial peptides: application as antinflammatory drugs in a murine model.

PubMed

Capparelli, Rosanna; De Chiara, Francesco; Nocerino, Nunzia; Montella, Rosa Chiara; Iannaccone, Marco; Fulgione, Andrea; Romanelli, Alessandra; Avitabile, Concetta; Blaiotta, Giuseppe; Capuano, Federico

2012-11-17

Antimicrobial peptides (AMPs) are an ancient group of defense molecules. AMPs are widely distributed in nature (being present in mammals, birds, amphibians, insects, plants, and microorganisms). They display bactericidal as well as immunomodulatory properties. The aim of this study was to investigate the antimicrobial and anti-inflammatory activities of a combination of two AMPs (temporin B and the royal jellein I) against Staphylococcus epidermidis. The temporin B (TB-KK) and the royal jelleins I, II, III chemically modified at the C terminal (RJI-C, RJII-C, RJIII-C), were tested for their activity against 10 different Staphylococcus epidermidis strains, alone and in combination. Of the three royal jelleins, RJI-C showed the highest activity. Moreover, the combination of RJI-C and TB-KK (MIX) displayed synergistic activity. In vitro, the MIX displayed low hemolytic activity, no NO2- production and the ability to curb the synthesis of the pro-inflammatory cytokines TNF-α and IFN-γ to the same extent as acetylsalicylic acid. In vivo, the MIX sterilized mice infected with Staphylococcus epidermidis in eleven days and inhibited the expression of genes encoding the prostaglandin-endoperoxide synthase 2 (COX-2) and CD64, two important parameters of inflammation. The study shows that the MIX - a combination of two naturally occurring peptides - displays both antimicrobial and anti-inflammatory activities.

Antimicrobial isothiocyanates from the seeds of Moringa oleifera Lam.

PubMed

Padla, Eleanor P; Solis, Ludivina T; Levida, Ruel M; Shen, Chien-Chang; Ragasa, Consolacion Y

2012-01-01

4-(alpha-L-Rhamnosyloxy)benzyl isothiocyanate (1) and 4-(4'-O-acetyl-alpha-L-rhamnosyloxy)-benzyl isothiocyanate (2) isolated from Moringa oleifera seeds were screened for their antibacterial activities against Staphylococcus aureus, Staphylococcus epidermidis, Bacillus subtilis, Escherichia coli, Enterobacter aerogenes, Klebsiella pneumoniae, and Pseudomonas aeruginosa, and for their antifungal activities against Candida albicans, Trichophyton rubrum, and Epidermophyton floccosum using the disk diffusion method. Isothiocyanates 1 and 2 were found active at the lowest inhibitory concentration of 1 mg/ml against all Gram-positive bacteria tested (S. aureus, S. epidermidis, B. subtilis) and against the dermatophytic fungi E. floccosum and T. rubrum. Statistically significant differences were found between the mean inhibition zones (IZ) of 1 and 2 and the standard drugs, ofloxacin and clotrimazole. The minimum inhibitory concentration (MIC) values confirmed the good antimicrobial activity of 1 and 2 against S. aureus, good to moderate activity against S. epidermidis, moderate activity against B. subtilis, and weak activity against E. floccosum and T. rubrum. The in vitro bactericidal effect of 1 and 2 against the Gram-positive bacterial strains tested is suggested by MBC:MIC ratios of 2:1.

Versatility of Biofilm Matrix Molecules in Staphylococcus epidermidis Clinical Isolates and Importance of Polysaccharide Intercellular Adhesin Expression during High Shear Stress

PubMed Central

Schaeffer, Carolyn R.; Hoang, Tra-My N.; Sudbeck, Craig M.; Alawi, Malik; Tolo, Isaiah E.; Robinson, D. Ashley; Horswill, Alexander R.; Rohde, Holger

2016-01-01

ABSTRACT Staphylococcus epidermidis is a leading cause of hospital-associated infections, including those of intravascular catheters, cerebrospinal fluid shunts, and orthopedic implants. Multiple biofilm matrix molecules with heterogeneous characteristics have been identified, including proteinaceous, polysaccharide, and nucleic acid factors. Two of the best-studied components in S. epidermidis include accumulation-associated protein (Aap) and polysaccharide intercellular adhesin (PIA), produced by the enzymatic products of the icaADBC operon. Biofilm composition varies by strain as well as environmental conditions, and strains producing PIA-mediated biofilms are more robust. Clinically, biofilm-mediated infections occur in a variety of anatomical sites with diverse physiological properties. To test the hypothesis that matrix composition exhibits niche specificity, biofilm-related genetic and physical properties were compared between S. epidermidis strains isolated from high-shear and low-shear environments. Among a collection of 105 clinical strains, significantly more isolates from high-shear environments carried the icaADBC operon than did those from low-shear settings (43.9% versus 22.9%, P < 0.05), while there was no significant difference in the presence of aap (77.2% versus 75.0%, P > 0.05). Additionally, a significantly greater number of high-shear isolates were capable of forming biofilm in vitro in a microtiter assay (82.5% versus 45.8%, P < 0.0001). However, even among high-shear clinical isolates, less than half contained the icaADBC locus; therefore, we selected for ica-negative variants with increased attachment to abiotic surfaces to examine PIA-independent biofilm mechanisms. Sequencing of selected variants identified substitutions capable of enhancing biofilm formation in multiple genes, further highlighting the heterogeneity of S. epidermidis biofilm molecules and mechanisms. IMPORTANCE Staphylococcus epidermidis is a leading cause of infections related to biomaterials, mostly due to their ability to form biofilm. Biofilm accumulation mechanisms vary, including those that are dependent on specific proteins, environmental DNA (eDNA), or polysaccharide intercellular adhesin (PIA). We found that those isolates obtained from high-shear environments, such as the lumen of a catheter, are more likely to produce PIA-mediated biofilms than those isolates obtained from a low-shear biomaterial-related infection. This suggests that PIA functions as a mechanism that is protective against shear flow. Finally, we performed selection experiments documenting the heterogeneity of biofilm accumulation molecules that function in the absence of PIA, further documenting the biofilm-forming potential of S. epidermidis. PMID:27747298

Mechanisms of Staphylococcus epidermidis adhesion to model biomaterial surfaces: Establising a link between thrombosis and infection

NASA Astrophysics Data System (ADS)

Higashi, Julie Miyo

Infections involving Staphylococcus epidermidis remain a life threatening complication associated with the use of polymer based cardiovascular devices. One of the critical steps in infection pathogenesis is the adhesion of the bacteria to the device surface. Currently, mechanisms of S. epidermidis adhesion are incompletely understood, but are thought to involve interactions between bacteria, device surface, and host blood elements in the form of adsorbed plasma proteins and surface adherent platelets. Our central hypothesis is that elements participating in thrombosis also promote S. epidermidis adhesion by specifically binding to the bacterial surface. The adhesion kinetics of S. epidermidis RP62A to host modified model biomaterial surface octadecyltrichlorosilane (OTS) under hydrodynamic shear conditions were characterized. Steady state adhesion to adsorbed proteins and surface adherent platelets was achieved at 90-120 minutes and 60-90 minutes, respectively. A dose response curve of S. epidermidis adhesion in the concentration range of 10sp7{-}10sp9 bac/mL resembled a multilayer adsorption isotherm. Increasing shear stress was found to LTA, and other LTA blocking agents significantly decreased S. epidermidis adhesion to the fibrin-platelet clots, suggesting that this interaction between S. epidermidis and fibrin-platelet clots is specific. Studies evaluated the adhesion of S. epidermidis to polymer immobilized heparin report conflicting results. Paulsson et al., showed that coagulase negative staphylococci adhered in comparable numbers to both immobilized heparin and nonheparinized surfaces, while exhibiting significantly greater adhesion to both surfaces than S. aureus. Preadsorption of the surfaces with specific heparin binding plasma proteins vitronectin, fibronectin, laminin, and collagen significantly increased adhesion. It was postulated that immobilized heparin contained binding sites for the plasma proteins, exposing bacteria binding domains of the protein. Aggregation of heparin coated (adsorbed) polystyrene beads by the same S. epidermidis strains did not correlate with the adherence assays on the immobilized heparin surfaces and staphylococcal binding was dependent on media ionic strength and pH, suggesting that the conformation of the heparin polysaccharide chains was crucial to the interaction (132). Another study by Arciola et al., showed that heparin modified PMMA intraocular lenses sustained significantly less adherent bacteria than unmodified PMMA lenses, and that the chromatogram of structural fatty acids of only the S. epidermidis adherent to heparin modified PMMA changed (133). Because neither of these investigators thoroughly characterized their heparin modified surfaces, the difference in their results could easily be explained by the notorious heterogeneity of the heparin molecular weight, bioactivity, or surface coverage on these polymers.

Chemical composition of the SFE-CO extracts from Cajanus cajan (L.) Huth and their antimicrobial activity in vitro and in vivo.

PubMed

Zu, Yuan-gang; Liu, Xiao-lei; Fu, Yu-jie; Wu, Nan; Kong, Yu; Wink, Michael

2010-12-01

The in vitro and in vivo antimicrobial activities of SFE-CO₂(supercritical fluid extraction) extracts and ethanol extracts from Cajanus cajan (L.) Huth were investigated. The flavonoid compounds orientin, vitexin, isovitexin, pinostrobin and the stilbene cajaninstilbene acid were detected in SFE-CO₂ extracts by HPLC-DAD. In vitro antimicrobial activities of the extracts were evaluated against eight microbial strains (the bacteria Staphylococcus epidermidis, Staphylococcus aureus, Bacillus subtilis, Proteus vulgaris, Pseudomonas aeruginosa, Escherichia coli; and the fungi Aspergillus niger and Candida albicans). A marked inhibitory effect of the SFE extracts was observed against Staphylococcus epidermidis, Staphylococcus aureus and Bacillus subtilis. The IC(50) of SFE-CO₂ extracts ranged from 0.0557 mg/ml to 0.0689 mg/ml consisting of cancer (MCF-7 (0.0557 mg/ml)) as well as non-cancer (BHK-21 (0.0641 mg/ml), RAW264.7 (0.0689 mg/ml) and Vero (0.0625 mg/ml)) cells. Flow cytometry (FCM) was used to analyze death rate of the most sensitive strain (Staphylococcus aureus) caused by the SFE extracts. Additionally, the whole cell proteins of Staphylococcus aureus were analyzed by SDS-PAGE to detect if there were changes in protein patterns. In vivo antimicrobial activity was studies in mice that had been inoculated with Staphylococcus aureus. The potential mechanism of antimicrobial activity in vivo was studied by histopathology. Copyright © 2010 Elsevier GmbH. All rights reserved.

Mutations in the quinolone resistance determining region in Staphylococcus epidermidis recovered from conjunctiva and their association with susceptibility to various fluoroquinolones

PubMed Central

Yamada, M; Yoshida, J; Hatou, S; Yoshida, T; Minagawa, Y

2008-01-01

Background: Staphylococcus epidermidis is one of the prominent pathogens in ocular infection. The prevalence of mutations in the quinolone resistance determining region (QRDR) area in S epidermidis isolated from the ocular surface and its association with fluoroquinolone resistance has not been fully elucidated. Methods: Mutations in the QRDR of gyrA, gyrB, parC, and parE genes of 138 isolates of S epidermidis recovered from the human conjunctival flora were analysed. The minimal inhibitory concentrations (MICs) of four fluoroquinolones (levofloxacin, gatifloxacin, moxifloxacin and tosufloxacin) against these isolates were also determined using agar dilution methods. Results: The MIC90 values of levofloxacin, gatifloxacin, moxifloxacin and tosufloxacin were 3.13, 1.56, 0.78 and 3.13 μg/ml, respectively. The MIC values of all fluoroquinolones showed a bimodal distribution (susceptible strain and less susceptible strain). Mutations with amino acid substitution in the QRDR were present in 70 (50.7%) isolates. 19 different combinations of mutations were detected: 3 isolates (2.2%) had four mutations, 8 (5.8%) had three mutations, 43 (31.2%) had double mutations and 16 (11.6%) had single mutations. Isolates with mutations in the QRDR of both gyrA and parC (n = 53) were less susceptible to fluoroquinolones. Conclusions: The present findings show that approximately half the S epidermidis isolates from the normal human conjunctiva have mutation(s) in the QRDR. The presence of mutations in both gyrA and parC is strongly associated with reduced susceptibility to fluoroquinolones. PMID:18460536

Introducing Urtica dioica, A Native Plant of Khuzestan, As an Antibacterial Medicinal Plant

PubMed Central

Motamedi, Hossein; Seyyednejad, Seyyed Mansour; Bakhtiari, Ameneh; Vafaei, Mozhan

2014-01-01

Background: Urtica dioica is a flowering plant with long history of use in folk medicine and as a food source. Objectives: This study examined in vitro antibacterial potential of alcoholic extracts of U. dioica. Materials and Methods: Hydroalcoholic extracts from aerial parts were prepared using aqueous solution of ethanol and methanol and their inhibitory effects against clinical isolates was examined by disc diffusion method at different doses. Minimum inhibitory concentrations (MIC) and minimum bactericidal concentration (MBC) indexes were also investigated. The scanning electron microscopy (SEM) analysis was also performed to find structural changes of affected bacteria consequent to exposing with extracts. Results: Both extracts were active against Bacillus cereus, Staphylococcus aureus, Staphylococcus epidermidis, and Escherichia coli with respectively 16, 10, 18, and 14 mm (methanolic) and 11, 9, 17, and 16 mm (ethanolic) inhibition zone. The MIC of ethanolic extract against S. epidermidis and E. coli was respectively 10 and 40 mg/mL. The MIC of methanolic extract against S. aureus and S. epidermidis was 40 and 10 mg/mL, respectively. The MBC was found only for S. epidermidis (20 mg/mL). In SEM analysis the round shape of S. epidermidis was changed and irregular shapes were appeared, which suggest that the main target of these extracts was cell wall. Conclusions: Extracts of U. dioica showed significant antibacterial effect against some clinically important pathogenic bacteria. Based on the obtained results it can be concluded that U. dioica is useful as antibacterial and bactericidal agent in treating infectious diseases. PMID:25625045

Identification of Genes Controlled by the Essential YycFG Two-Component System Reveals a Role for Biofilm Modulation in Staphylococcus epidermidis.

PubMed

Xu, Tao; Wu, Yang; Lin, Zhiwei; Bertram, Ralph; Götz, Friedrich; Zhang, Ying; Qu, Di

2017-01-01

Biofilms play a crucial role in the pathogenicity of Staphylococcus epidermidis , while little is known about whether the essential YycFG two-component signal transduction system (TCS) is involved in biofilm formation. We used antisense RNA (asRNA) to silence the yycFG TCS in order to study its regulatory functions in S. epidermidis . Strain 1457 expressing asRNA yycF exhibited a significant delay (~4-5 h) in entry to log phase, which was partially complemented by overexpressing ssaA . The expression of asRNA yycF and asRNA yycG resulted in a 68 and 50% decrease in biofilm formation at 6 h, respectively, while they had no significant inhibitory effect on 12 h biofilm formation. The expression of asRNA yycF led to a ~5-fold increase in polysaccharide intercellular adhesion (PIA) production, but it did not affect the expression of accumulation-associated protein (Aap) or the release of extracellular DNA. Consistently, quantitative real-time PCR showed that silencing yycF resulted in an increased transcription of biofilm-related genes, including icaA, arlR, sarA, sarX , and sbp . An in silico search of the YycF regulon for the conserved YycF recognition pattern and a modified motif in S. epidermidis , along with additional gel shift and DNase I footprinting assays, showed that arlR, sarA, sarX , and icaA are directly regulated by YycF. Our data suggests that YycFG modulates S. epidermidis biofilm formation in an ica-dependent manner.

Identification of Genes Controlled by the Essential YycFG Two-Component System Reveals a Role for Biofilm Modulation in Staphylococcus epidermidis

PubMed Central

Xu, Tao; Wu, Yang; Lin, Zhiwei; Bertram, Ralph; Götz, Friedrich; Zhang, Ying; Qu, Di

2017-01-01

Biofilms play a crucial role in the pathogenicity of Staphylococcus epidermidis, while little is known about whether the essential YycFG two-component signal transduction system (TCS) is involved in biofilm formation. We used antisense RNA (asRNA) to silence the yycFG TCS in order to study its regulatory functions in S. epidermidis. Strain 1457 expressing asRNAyycF exhibited a significant delay (~4–5 h) in entry to log phase, which was partially complemented by overexpressing ssaA. The expression of asRNAyycF and asRNAyycG resulted in a 68 and 50% decrease in biofilm formation at 6 h, respectively, while they had no significant inhibitory effect on 12 h biofilm formation. The expression of asRNAyycF led to a ~5-fold increase in polysaccharide intercellular adhesion (PIA) production, but it did not affect the expression of accumulation-associated protein (Aap) or the release of extracellular DNA. Consistently, quantitative real-time PCR showed that silencing yycF resulted in an increased transcription of biofilm-related genes, including icaA, arlR, sarA, sarX, and sbp. An in silico search of the YycF regulon for the conserved YycF recognition pattern and a modified motif in S. epidermidis, along with additional gel shift and DNase I footprinting assays, showed that arlR, sarA, sarX, and icaA are directly regulated by YycF. Our data suggests that YycFG modulates S. epidermidis biofilm formation in an ica-dependent manner. PMID:28491057

Composition and Antimicrobial Activity of Euphrasia rostkoviana Hayne Essential Oil

PubMed Central

Novy, Pavel; Davidova, Hana; Serrano-Rojero, Cecilia Suqued; Rondevaldova, Johana; Pulkrabek, Josef

2015-01-01

Eyebright, Euphrasia rostkoviana Hayne (Scrophulariaceae), is a medicinal plant traditionally used in Europe for the treatment of various health disorders, especially as eyewash to treat eye ailments such as conjunctivitis and blepharitis that can be associated with bacterial infections. Some Euphrasia species have been previously reported to contain essential oil. However, the composition and bioactivity of E. rostkoviana oil are unknown. Therefore, in this study, we investigated the chemical composition and antimicrobial activity of the eyebright essential oil against some organisms associated with eye infections: Enterococcus faecalis, Escherichia coli, Klebsiella pneumoniae, Staphylococcus aureus, S. epidermidis, Pseudomonas aeruginosa, and Candida albicans. GC-MS analysis revealed more than 70 constituents, with n-hexadecanoic acid (18.47%) as the main constituent followed by thymol (7.97%), myristic acid (4.71%), linalool (4.65%), and anethole (4.09%). The essential oil showed antimicrobial effect against all organisms tested with the exception of P. aeruginosa. The best activity was observed against all Gram-positive bacteria tested with the minimum inhibitory concentrations of 512 µg/mL. This is the first report on the chemical composition of E. rostkoviana essential oil and its antimicrobial activity. PMID:26000025

Composition and Antimicrobial Activity of Euphrasia rostkoviana Hayne Essential Oil.

PubMed

Novy, Pavel; Davidova, Hana; Serrano-Rojero, Cecilia Suqued; Rondevaldova, Johana; Pulkrabek, Josef; Kokoska, Ladislav

2015-01-01

Eyebright, Euphrasia rostkoviana Hayne (Scrophulariaceae), is a medicinal plant traditionally used in Europe for the treatment of various health disorders, especially as eyewash to treat eye ailments such as conjunctivitis and blepharitis that can be associated with bacterial infections. Some Euphrasia species have been previously reported to contain essential oil. However, the composition and bioactivity of E. rostkoviana oil are unknown. Therefore, in this study, we investigated the chemical composition and antimicrobial activity of the eyebright essential oil against some organisms associated with eye infections: Enterococcus faecalis, Escherichia coli, Klebsiella pneumoniae, Staphylococcus aureus, S. epidermidis, Pseudomonas aeruginosa, and Candida albicans. GC-MS analysis revealed more than 70 constituents, with n-hexadecanoic acid (18.47%) as the main constituent followed by thymol (7.97%), myristic acid (4.71%), linalool (4.65%), and anethole (4.09%). The essential oil showed antimicrobial effect against all organisms tested with the exception of P. aeruginosa. The best activity was observed against all Gram-positive bacteria tested with the minimum inhibitory concentrations of 512 µg/mL. This is the first report on the chemical composition of E. rostkoviana essential oil and its antimicrobial activity.

Cytotoxic and antibacterial angucycline- and prodigiosin-analogues from the deep-sea derived Streptomyces sp. SCSIO 11594.

PubMed

Song, Yongxiang; Liu, Guangfu; Li, Jie; Huang, Hongbo; Zhang, Xing; Zhang, Hua; Ju, Jianhua

2015-03-16

Two new C-glycoside angucyclines, marangucycline A (1) and marangucycline B (2), along with three known compounds, dehydroxyaquayamycin (3), undecylprodigiosin (4) and metacycloprodigiosin (5), have been identified as products of the deep-sea sediment strain Streptomyces sp. SCSIO 11594. New structures were elucidated on the basis of HRESIMS, 1D and 2D NMR analyses and comparisons to previously reported datasets. Compounds 2 and 4 displayed in vitro cytotoxicity against four cancer cell lines A594, CNE2, HepG2, MCF-7 superior to those obtained with cisplatin, the positive control. Notably, compound 2 bearing a keto-sugar displayed significant cytotoxicity against cancer cell lines with IC50 values ranging from 0.24 to 0.56 μM; An IC50 value of 3.67 μM was found when using non-cancerous hepatic cell line HL7702, demonstrating the cancer cell selectivity of 2. Compounds 1-3 were proved to have weak antibacterial activities against Enterococcus faecalis ATCC29212 with an MIC value of 64.0 μg/mL. Moreover, 3 displayed selective antibacterial activity against methicillin-resistant Staphylococcus epidermidis shhs-E1 with an MIC value of 16.0 μg/mL.

In Vitro Antibacterial and Antibiotic Resistance Modifying Effect of Bioactive Plant Extracts on Methicillin-Resistant Staphylococcus epidermidis

PubMed Central

Chovanová, Romana; Vaverková, Štefánia

2013-01-01

The crude extracts of plants from Asteraceae and Lamiaceae family and essential oils from Salvia officinalis and Salvia sclarea were studied for their antibacterial as well as antibiotic resistance modifying activity. Using disc diffusion and broth microdilution assays we determined higher antibacterial effect of three Salvia spp. and by evaluating the leakage of 260 nm absorbing material we detected effect of extracts and, namely, of essential oils on the disruption of cytoplasmic membrane. The evaluation of in vitro interactions between plant extracts and oxacillin described in terms of fractional inhibitory concentration (FIC) indices revealed synergistic or additive effects of plant extracts and clearly synergistic effects of essential oil from Salvia officinalis with oxacillin in methicillin-resistant Staphylococcus epidermidis. PMID:24222768

Production and Purification of a Staphylococcus epidermidis Bacteriocin

PubMed Central

Jetten, A. M.; Vogels, G. D.; de Windt, F.

1972-01-01

Liquid cultures of Staphylococcus epidermidis 1580 contained rather small amounts of a bacteriocin, staphylococcin 1580, which was found both in the supernatant fluid and in the cell pellet. It could be extracted from the cells with 5% NaCl solution. The staphylococcin production could not be induced by ultraviolet irradiation or treatment with mitomycin C. Bacteria grown on semisolid medium produced a much larger amount of the compound with a high specific activity. The staphylococcin was purified by ammonium sulfate precipitation, ultracentrifugation, and chromatography on Sephadex columns. The purified material was homogeneous on polyacrylamide gel electrophoresis. The molecular weight was between 150,000 and 400,000. The bacteriocin was composed of protein, carbohydrate, and lipid and consisted of subunits exhibiting a molecular weight of about 20,000. Images PMID:5079063

Comparison on conjunctival sac bacterial flora of the seniors with dry eye in Ganzi autonomous prefecture

PubMed Central

Zhang, Yue; Liu, Zhi-Rong; Chen, Hui; Fan, Ying-Chuan; Duo, Ji; Zheng, Hong; Wang, Guang-Jin; Li, Yu-Chan; Jiachu, Dan-Ba; Zewang, Ge-Ma

2013-01-01

AIM To compare the bacterial flora in palpebral conjunctiva of xerophthalmia seniors of Tibetan, Yi and Han, and analyze the differences and similarities of the bacteria. METHODS The test subjects were selected from 2 Tibetan, 2 Yi and 3 Han populated places, respectively. Total 222 seniors (444 eyes) with dry eye were examined. Secretion was collected from the palpebral conjunctiva of the subjects and then inoculated onto a blood agar plate. After 48h of incubation, the bacteria were examined for the differences and similarities between different ethnics. RESULTS There was no significant difference (P>0.05) of Gram stain characterization, dominant bacteria and number of the bacterial species present in oxrophthalmia patients among Tibetan, Yi and Han nationalities. The bacteria presented in all groups include staphylococcus epidermidis, corynebacterium, micrococcus luteu, intracellular bacteria sphingomonas, pseudomonas aeruginosa. The bacteria detected from the two of three ethnic groups were staphylococcus aureus, staphylococcus haemolyticus, escherichia coli, kytococcus sedentarius, streptococcus angina, micrococcus lylae, and staphylococcus heads. The incidence rate of bacteria-associated dry eye in Tibetan population was significantly lower than that of Han and Yi population. CONCLUSION There is no significant difference in the bacteria flora of palpebral conjunctiva observed among dry eye elder populations of Tibetan, Yi and Han people. All of staphylococcus epidermidis, corynebacterium, micrococcus luteu, intracellular bacteria sphingomonas, pseudomonas aeruginosa, staphylococcus aureus, staphylococcus haemolyticus, escherichia coli, kytococcus sedentarius, streptococcus angina, micrococcus lylae and staphylococcus heads are common bacteria flora of the three nationalities inhibiting in this area. PMID:23991377

Real-Time PCR Diagnostics for Detecting and Identifying Potential Bioweapons

DTIC Science & Technology

2003-11-18

pestis Bacillus cereus Salmonella enteritidis Yersinia pestis Bacillus thurigiensis Serratia odorifera Yersinia pestis Bacillus coagulans Shigella...10fg NTC 100pg-opt 10pg-opt 1pg-opt 100fg-opt 10fg-opt NTC-opt USAMRIID Specificity Organism Organism Organism Acineobacter baumanni Bacillus subtilis...var niger Staphylococcus saprophyticus Bacillus anthracis BA0068 Bacillus bronchiseptica Staphylococcus epidermidis Bacillus anthracis Clostridium

Evaluation of High-Resolution Melting Curve Analysis of Ligation-Mediated Real-Time PCR, a Rapid Method for Epidemiological Typing of ESKAPE (Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Enterobacter Species) Pathogens

PubMed Central

Ryberg, Anna; Billström, Hanna; Hällgren, Anita; Nilsson, Lennart E.; Marklund, Britt-Inger; Olsson-Liljequist, Barbro; Schön, Thomas

2014-01-01

A single-tube method, ligation-mediated real-time PCR high-resolution melt analysis (LMqPCR HRMA), was modified for the rapid typing of Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Enterobacter spp. (ESKAPE) pathogens. A 97% agreement (60/62 isolates) was achieved in comparison to pulsed-field gel electrophoresis (PFGE) results, which indicates that LMqPCR HRMA is a rapid and accurate screening tool for monitoring nosocomial outbreaks. PMID:25232168

Antibacterial effect of plasma rich in growth factors (PRGF®-Endoret®) against Staphylococcus aureus and Staphylococcus epidermidis strains.

PubMed

Anitua, E; Alonso, R; Girbau, C; Aguirre, J J; Muruzabal, F; Orive, G

2012-08-01

Formulations containing plasma rich in growth factors (PRGF) are opening new avenues in the field of regenerative medicine. To evaluate the potential antimicrobial effects of a product (plasma rich in growth factors; PRGF(®)-Endoret(®)) against both methicillin-sensitive and methicillin-resistant Staphylococcus aureus and Staphylococcus epidermidis. The potential effect of incorporating the patient's leucocytes into the PRGF formulation (F3+leu) was also studied. Blood samples were obtained from five healthy volunteers and used to prepare each type of PRGF (F1, F3 and F3+leu). Various biological assays were performed to compare the characteristics of the different formulations, including measurement of the concentration of platelets and leucocytes, and assays of coagulation. The microbiological activity of PRGF-Endoret against both staphylococcal strains was performed by counting the number of the surviving bacterial colonies after incubation at 0, 4 and 8 h with the different formulations. The three PRGF-Endoret formulations evaluated were enriched in platelets by 1.10, 2.57 and 1.89 times, respectively, and the leucocyte concentration in the F3+leu sample was increased by 3.9 times. We found that all formulations had a strong bacteriostatic effect, especially in the first 4 h after application. All formulations had an antibacterial effect at 4 h for three of the four strains, with the exception of methicillin-sensitive S. epidermidis. No differences in the bacterial inhibitory effect were found between the formulations. This is the first time different formulations of this product have been evaluated, and the results suggest that PRGF-Endoret could be used in the fight against postoperative and wound infections. © The Author(s). CED © 2012 British Association of Dermatologists.

Growth Behavior of E. coli, Enterococcus and Staphylococcus Species in the Presence and Absence of Sub-inhibitory Antibiotic Concentrations: Consequences for Interpretation of Culture-Based Data.

PubMed

Heß, Stefanie; Gallert, Claudia

2016-11-01

Culture-based approaches are used to monitor, e.g., drinking water or bathing water quality and to investigate species diversity and antibiotic resistance levels in environmental samples. For health risk assessment, it is important to know whether the growing cultures display the actual abundance of, e.g., clinically relevant antibiotic resistance phenotypes such as vancomycin-resistant Enterococcus faecium/Enterococcus faecalis (VRE) or methicillin-resistant Staphylococcus aureus. In addition, it is important to know whether sub-inhibitory antibiotic concentrations, which are present in surface waters, favor the growth of antibiotic-resistant strains. Therefore, clinically relevant bacteria were isolated from different water sources and the growth behavior of 58 Escherichia coli, 71 Enterococcus, and 120 Staphylococcus isolates, belonging to different species and revealing different antibiotic resistance patterns, was studied with respect to "environmental" antibiotic concentrations. The finding that VRE could only be detected after specific enrichment can be explained by their slow growth compared to non-resistant strains. Interpreting their absence in standardized culture-based methods as nonexistent might be a fallacy. Sub-inhibitory antibiotic concentrations that were detected in sewage and receiving river water did not specifically promote antibiotic-resistant strains. Generally, those antibiotics that influenced cell metabolism directly led to slightly reduced growth rates and less than maximal optical densities after 48 h of incubation.

Amino acid conversions by coagulase-negative staphylococci in a rich medium: Assessment of inter- and intraspecies heterogeneity.

PubMed

Stavropoulou, Despoina Angeliki; Borremans, Wim; De Vuyst, Luc; De Smet, Stefaan; Leroy, Frédéric

2015-11-06

The ability of coagulase-negative staphylococci (CNS) to convert amino acids into volatile compounds and biogenic amines was investigated after 24h and 48 h of incubation in a rich medium (brain heart infusion). Volatile compounds were measured with static-headspace gas chromatography and mass spectrometry (SH-GC-MS); biogenic amine measurements were carried out with a newly developed method based on ultra-performance liquid chromatography coupled to tandem mass spectrometry (UPLC-MS/MS). In total, 56 CNS strains from five different species were used, namely Staphylococcus carnosus, Staphylococcus epidermidis, Staphylococcus equorum, Staphylococcus saprophyticus, and Staphylococcus xylosus. With respect to the production of volatile compounds, the leucine-derived 3-methyl butanol was produced over time by most CNS strains, up to 52 μM for S. xylosus W1-1 after 48 h of incubation. The average production by strains of S. xylosus was significantly higher than for strains of S. carnosus, whereas strains of S. epidermidis turned out to be poor producers. Yet, differences between species were blurred to a large degree because of the high strain variability. A few strains also produced 3-methyl butanal on top of the amount that was already present in the medium background, although most CNS led to a decrease of this compound. Concerning biogenic amines, the average total concentrations per species remained below 100 μM after 48 h of incubation. The most abundant variant was 2-phenylethylamine (PEA), especially within S. carnosus (average of 65 μM after 48 h of incubation). Yet, some individual strains were able to produce higher concentrations, as found for the PEA production of 295 μM by S. epidermidis ATCC 12228 after 48 h of incubation. The insights obtained during this study indicate heterogeneity and are of importance in view of both starter culture development and the evaluation of a spontaneously established CNS microbiota in artisan-type meat fermentations. Copyright © 2015 Elsevier B.V. All rights reserved.

Bile Culture and Susceptibility Testing of Malignant Biliary Obstruction via PTBD

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yu Haipeng; Guo Zhi, E-mail: jieruke@yahoo.com.cn; Xing Wenge

Purpose: To assess the information obtained by bile culture and susceptibility testing for malignant biliary obstruction by a retrospective one-center study. Methods: A total of 694 patients with malignant biliary obstruction received percutaneous transhepatic biliary drainage during the period July 2003 to September 2010, and subsequently, bile specimens were collected during the procedure. Among the 694 patients, 485 were men and 209 were women, ranging in age from 38 to 78 years (mean age 62 years). Results: A total of 42.9% patients had a positive bile culture (298 of 694). Further, 57 species of microorganisms and 342 strains were identified;more » gram-positive bacteria accounted for 50.9% (174 of 342) and gram-negative bacteria accounted for 41.5% (142 of 342) of these strains. No anaerobes were obtained by culture during this study. The most common microorganisms were Enterococcus faecalis (41 of 342, 11.9%), Escherichia coli (34 of 342, 9.9%), Klebsiella pneumoniae (28 of 342, 8.2%), Staphylococcus epidermidis (19 of 342, 5.5%), Enterococcus (18 of 342, 5.3%), and Enterobacter cloacae (16 of 342, 4.7%). The percentage of {beta}-lactamase-producing gram-positive bacteria was 27.6% (48 of 174), and the percentage of gram-negative bacteria was 19.7% (28 of 142). The percentage of enzyme-producing Escherichia coli was 61.7% (21 of 34). Conclusion: The bile cultures in malignant biliary obstruction are different from those in the Tokyo Guidelines and other benign biliary obstruction researches, which indicates that a different antibacterial therapy should be applied. Thus, knowledge of the antimicrobial susceptibility data could aid in the better use of antibiotics for the empirical therapy of biliary infection combined with malignant biliary obstruction.« less

Monotreme Lactation Protein Is Highly Expressed in Monotreme Milk and Provides Antimicrobial Protection

PubMed Central

Enjapoori, Ashwantha Kumar; Grant, Tom R.; Nicol, Stewart C.; Lefèvre, Christophe M.; Nicholas, Kevin R.; Sharp, Julie A.

2014-01-01

Monotremes (platypus and echidna) are the descendants of the oldest ancestor of all extant mammals distinguished from other mammals by mode of reproduction. Monotremes lay eggs following a short gestation period and after an even briefer incubation period, altricial hatchlings are nourished over a long lactation period with milk secreted by nipple-less mammary patches located on the female’s abdomen. Milk is the sole source of nutrition and immune protection for the developing young until weaning. Using transcriptome and mass spectrometry analysis of milk cells and milk proteins, respectively, a novel Monotreme Lactation Protein (MLP) was identified as a major secreted protein in milk. We show that platypus and short-beaked echidna MLP genes show significant homology and are unique to monotremes. The MLP transcript was shown to be expressed in a variety of tissues; however, highest expression was observed in milk cells and was expressed constitutively from early to late lactation. Analysis of recombinant MLP showed that it is an N-linked glycosylated protein and biophysical studies predicted that MLP is an amphipathic, α-helical protein, a typical feature of antimicrobial proteins. Functional analysis revealed MLP antibacterial activity against both opportunistic pathogenic Staphylococcus aureus and commensal Enterococcus faecalis bacteria but showed no effect on Escherichia coli, Pseudomonas aeruginosa, Staphylococcus epidermidis, and Salmonella enterica. Our data suggest that MLP is an evolutionarily ancient component of milk-mediated innate immunity absent in other mammals. We propose that MLP evolved specifically in the monotreme lineage supporting the evolution of lactation in these species to provide bacterial protection, at a time when mammals lacked nipples. PMID:25245409

DOE Office of Scientific and Technical Information (OSTI.GOV)

Barta, Michael L.; Skaff, D. Andrew; McWhorter, William J.

The polyisoprenoid compound undecaprenyl phosphate is required for biosynthesis of cell wall peptidoglycans in Gram-positive bacteria, including pathogenic Enterococcus, Streptococcus, and Staphylococcus spp. In these organisms, the mevalonate pathway is used to produce the precursor isoprenoid, isopentenyl 5-diphosphate. Mevalonate diphosphate decarboxylase (MDD) catalyzes formation of isopentenyl 5-diphosphate in an ATP-dependent irreversible reaction and is therefore an attractive target for inhibitor development that could lead to new antimicrobial agents. To facilitate exploration of this possibility, we report the crystal structure of Staphylococcus epidermidis MDD (1.85 {angstrom} resolution) and, to the best of our knowledge, the first structures of liganded MDD. Thesemore » structures include MDD bound to the mevalonate 5-diphosphate analogs diphosphoglycolyl proline (2.05 {angstrom} resolution) and 6-fluoromevalonate diphosphate (FMVAPP; 2.2 {angstrom} resolution). Comparison of these structures provides a physical basis for the significant differences in K{sub i} values observed for these inhibitors. Inspection of enzyme/inhibitor structures identified the side chain of invariant Ser{sup 192} as making potential contributions to catalysis. Significantly, Ser {yields} Ala substitution of this side chain decreases k{sub cat} by {approx}10{sup 3}-fold, even though binding interactions between FMVAPP and this mutant are similar to those observed with wild type MDD, as judged by the 2.1 {angstrom} cocrystal structure of S192A with FMVAPP. Comparison of microbial MDD structures with those of mammalian counterparts reveals potential targets at the active site periphery that may be exploited to selectively target the microbial enzymes. These studies provide a structural basis for previous observations regarding the MDD mechanism and inform future work toward rational inhibitor design.« less

The effect of LED-light action on microbial colony forming ability of several species of staphylococcus

NASA Astrophysics Data System (ADS)

Tuchina, Elena S.; Permyakova, Natalia F.; Tuchin, Valery V.

2007-05-01

Photodynamic therapy (PDT) now is widespread for treatment of the various skin infections caused by Propionibacterium acnes or Staphylococcii spp. We used PDT for influence on opportunistic microflora of human skin presented by Staphylococcus hominis, S. warnery, S. epidermidis S. aureus 209 P, S. aureus 69. Species S. epidermidis, S. aureus 209 P, S. hominis to some extent reduced colonies forming ability under action of dual wavelength LED-light (442 nm and 597 nm). For species S. warnery, S. aureus 69 the increase in CFU number under action of light relative to control was characteristic. Our experiments have shown, that phototherapy can be used for treatment of diseases associated with S. aureus 209 P. The doze 8 J/cm2 caused reduction in CFU of this species on 40% relative to control.

Fabrication of Acrylonitrile-Butadiene-Styrene Nanostructures with Anodic Alumina Oxide Templates, Characterization and Biofilm Development Test for Staphylococcus epidermidis

PubMed Central

Desrousseaux, Camille; Cueff, Régis; Aumeran, Claire; Garrait, Ghislain; Mailhot-Jensen, Bénédicte; Traoré, Ousmane; Sautou, Valérie

2015-01-01

Medical devices can be contaminated by microbial biofilm which causes nosocomial infections. One of the strategies for the prevention of such microbial adhesion is to modify the biomaterials by creating micro or nanofeatures on their surface. This study aimed (1) to nanostructure acrylonitrile-butadiene-styrene (ABS), a polymer composing connectors in perfusion devices, using Anodic Alumina Oxide templates, and to control the reproducibility of this process; (2) to characterize the physico-chemical properties of the nanostructured surfaces such as wettability using captive-bubble contact angle measurement technique; (3) to test the impact of nanostructures on Staphylococcus epidermidis biofilm development. Fabrication of Anodic Alumina Oxide molds was realized by double anodization in oxalic acid. This process was reproducible. The obtained molds present hexagonally arranged 50 nm diameter pores, with a 100 nm interpore distance and a length of 100 nm. Acrylonitrile-butadiene-styrene nanostructures were successfully prepared using a polymer solution and two melt wetting methods. For all methods, the nanopicots were obtained but inside each sample their length was different. One method was selected essentially for industrial purposes and for better reproducibility results. The flat ABS surface presents a slightly hydrophilic character, which remains roughly unchanged after nanostructuration, the increasing apparent wettability observed in that case being explained by roughness effects. Also, the nanostructuration of the polymer surface does not induce any significant effect on Staphylococcus epidermidis adhesion. PMID:26284922

Capillary isoelectric focusing--useful tool for detection of the biofilm formation in Staphylococcus epidermidis.

PubMed

Ruzicka, Filip; Horka, Marie; Hola, Veronika; Votava, Miroslav

2007-03-01

The biofilm formation is an important factor of S. epidermidis virulence. Biofilm-positive strains might be clinically more important than biofilm-negative ones. Unlike biofilm-negative staphylococci, biofilm-positive staphylococci are surrounded with an extracellular polysaccharide substance. The presence of this substance on the surface can affect physico-chemical properties of the bacterial cell, including surface charge. 73 S. epidermidis strains were examined for the presence of ica operon, for the ability to form biofilm by Christensen test tube method and for the production of slime by Congo red agar method. Isoelectric points (pI) of these strains were determined by means of Capillary Isoelectric Focusing. The biofilm negative strains focused near pI value 2.3, while the pI values of the biofilm positive strains were near 2.6. Isoelectric point is a useful criterion for the differentiation between biofilm-positive and biofilm-negative S. epidermidis strains.

Role of nanostructured gold surfaces on monocyte activation and Staphylococcus epidermidis biofilm formation

PubMed Central

Svensson, Sara; Forsberg, Magnus; Hulander, Mats; Vazirisani, Forugh; Palmquist, Anders; Lausmaa, Jukka; Thomsen, Peter; Trobos, Margarita

2014-01-01

The role of material surface properties in the direct interaction with bacteria and the indirect route via host defense cells is not fully understood. Recently, it was suggested that nanostructured implant surfaces possess antimicrobial properties. In the current study, the adhesion and biofilm formation of Staphylococcus epidermidis and human monocyte adhesion and activation were studied separately and in coculture in different in vitro models using smooth gold and well-defined nanostructured gold surfaces. Two polystyrene surfaces were used as controls in the monocyte experiments. Fluorescent viability staining demonstrated a reduction in the viability of S. epidermidis close to the nanostructured gold surface, whereas the smooth gold correlated with more live biofilm. The results were supported by scanning electron microscopy observations, showing higher biofilm tower formations and more mature biofilms on smooth gold compared with nanostructured gold. Unstimulated monocytes on the different substrates demonstrated low activation, reduced gene expression of pro- and anti-inflammatory cytokines, and low cytokine secretion. In contrast, stimulation with opsonized zymosan or opsonized live S. epidermidis for 1 hour significantly increased the production of reactive oxygen species, the gene expression of tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), IL-6, and IL-10, as well as the secretion of TNF-α, demonstrating the ability of the cells to elicit a response and actively phagocytose prey. In addition, cells cultured on the smooth gold and the nanostructured gold displayed a different adhesion pattern and a more rapid oxidative burst than those cultured on polystyrene upon stimulation. We conclude that S. epidermidis decreased its viability initially when adhering to nanostructured surfaces compared with smooth gold surfaces, especially in the bacterial cell layers closest to the surface. In contrast, material surface properties neither strongly promoted nor attenuated the activity of monocytes when exposed to zymosan particles or S. epidermidis. PMID:24550671

Molecular & phenotypic characterization of Staphylococcus epidermidis in implant related infections

PubMed Central

Prasad, Sujata; Nayak, N.; Satpathy, G.; Nag, H.L.; Venkatesh, P.; Ramakrishnan, S.; Ghose, Supriyo; Nag, T.C.

2012-01-01

Background & objectives: The discrimination between the Staphylococcus epidermidis colonizing the deep seated indwelling devices and those which are mere commensals has always been a challenge for the clinical microbiologist. This study was aimed to characterize the S. epidermidis isolates obtained from device related infection for their phenotypic and molecular markers of virulence and to see whether these markers can be used to differentiate the pathogenic S. epidermidis from the commensals. Methods: Fifty five S. epidermidis isolates from various device related infections such as endophthalmitis following intra-ocular lens (IOL) implantation, intravascular (IV) catheter related sepsis and orthopaedic implant infections, were studied for slime production, biotyping, antibiotic sensitivity; and mec A and ica positivity by the recommended procedures. Results: Twenty three (41.8%) isolates were multi-drug resistant, 26 (65.2%) were slime producers, 30 (54.5%) were adherent, 23 (41.8%) possessed the intercellular adhesin (ica) gene, and 28 (50.9%) harboured the mec A gene. Biotypes I and III were the commonest, most members of which were multi- drug resistant. Twenty two (73.3%) of the 30 adherent bacteria were slime producers as opposed to only 4 (16%) of the 25 non-adherent bacteria (P<0.001). A vast majority i.e. 21 (91.3%) of the 23 ica positive organisms were adherent to artificial surfaces in contrast to only 9 (28.1%) of the 32 non-ica positive organisms (P<0.001). Twenty (86.9%) of the 23 ica positive bacteria were slime producers, as opposed to only 6 (18.7%) of the 32 ica negative bacteria (P<0.001). Of the 23 multi-drug resistant isolates, 19 (82.6%) carried the mec A gene. Interpretation & conclusions: The present findings showed that ica AB and mec A were the two important virulence markers of S. epidermidis in implant infections and slime was responsible for the sessile mode of attachment on the devices. PMID:23041744

Anti-Biofilm Activity of a Long-Chain Fatty Aldehyde from Antarctic Pseudoalteromonas haloplanktis TAC125 against Staphylococcus epidermidis Biofilm

PubMed Central

Casillo, Angela; Papa, Rosanna; Ricciardelli, Annarita; Sannino, Filomena; Ziaco, Marcello; Tilotta, Marco; Selan, Laura; Marino, Gennaro; Corsaro, Maria M.; Tutino, Maria L.; Artini, Marco; Parrilli, Ermenegilda

2017-01-01

Staphylococcus epidermidis is a harmless human skin colonizer responsible for ~20% of orthopedic device-related infections due to its capability to form biofilm. Nowadays there is an interest in the development of anti-biofilm molecules. Marine bacteria represent a still underexploited source of biodiversity able to synthesize a broad range of bioactive compounds, including anti-biofilm molecules. Previous results have demonstrated that the culture supernatant of Antarctic marine bacterium Pseudoalteromonas haloplanktis TAC125 impairs the formation of S. epidermidis biofilm. Further, evidence supports the hydrophobic nature of the active molecule, which has been suggested to act as a signal molecule. In this paper we describe an efficient activity-guided purification protocol which allowed us to purify this anti-biofilm molecule and structurally characterize it by NMR and mass spectrometry analyses. Our results demonstrate that the anti-biofilm molecule is pentadecanal, a long-chain fatty aldehyde, whose anti-S. epidermidis biofilm activity has been assessed using both static and dynamic biofilm assays. The specificity of its action on S. epidermidis biofilm has been demonstrated by testing chemical analogs of pentadecanal differing either in the length of the aliphatic chain or in their functional group properties. Further, indications of the mode of action of pentadecanal have been collected by studying the bioluminescence of a Vibrio harveyi reporter strain for the detection of autoinducer AI-2 like activities. The data collected suggest that pentadecanal acts as an AI-2 signal. Moreover, the aldehyde metabolic role and synthesis in the Antarctic source strain has been investigated. To the best of our knowledge, this is the first report on the identification of an anti-biofilm molecule form from cold-adapted bacteria and on the action of a long-chain fatty aldehyde acting as an anti-biofilm molecule against S. epidermidis. PMID:28280714

Characterization of Staphylococcus epidermidis strains isolated from industrial cleanrooms under regular routine disinfection.

PubMed

Ribič, U; Klančnik, A; Jeršek, B

2017-05-01

The purpose of this study was the genotypic and phenotypic characterization of 57 strains of Staphylococcus epidermidis isolated from cleanroom environments, based on their biofilm formation and antimicrobial resistance profiles. Biofilm formation was investigated using real-time PCR (icaA, aap, bhp genes), the Congo red agar method and the crystal violet assay. The majority of the strains (59·7%; 34/57) did not form biofilms according to the crystal violet assay, although the biofilm-associated genes were present in 94·7% (54/57) of the strains. Of the biofilm formers (40·4%; 23/57), 39·1% (9/23) have been identified as strong biofilm formers (>4× crystal violet absorbance cut-off). Resistance to a commercial disinfectant and its quaternary ammonium active component, didecyl-dimethyl-ammonium chloride (DDAC), was determined according to minimum inhibitory concentrations (MICs) and the presence of the qac (quaternary ammonium compound) genes. More than 95% (55/57) of the Staph. epidermidis strains had the qacA/B and qacC genes, but not the other qac genes. The MICs for the disinfectant and DDAC varied among the Staph. epidermidis strains, although none were resistant. Although 59·6% of the Staph. epidermidis strains did not form biofilms and none were resistant to DDAC, more than 94% had the genetic basis for development of resistance to quaternary ammonium compounds, and among them at least 14·0% (8/57) might represent a high risk to cleanroom hygiene as strong biofim formers with qacA/B and qacC genes. To assure controlled cleanroom environments, bacterial strains isolated from cleanroom environments need to be characterized regularly using several investigative methods. © 2017 The Society for Applied Microbiology.

Activity of daptomycin- and vancomycin-loaded poly-epsilon-caprolactone microparticles against mature staphylococcal biofilms

PubMed Central

Ferreira, Inês Santos; Bettencourt, Ana F; Gonçalves, Lídia MD; Kasper, Stefanie; Bétrisey, Bertrand; Kikhney, Judith; Moter, Annette; Trampuz, Andrej; Almeida, António J

2015-01-01

The aim of the present study was to develop novel daptomycin-loaded poly-epsilon-caprolactone (PCL) microparticles with enhanced antibiofilm activity against mature biofilms of clinically relevant bacteria, methicillin-resistant Staphylococcus aureus (MRSA) and polysaccharide intercellular adhesin-positive Staphylococcus epidermidis. Daptomycin was encapsulated into PCL microparticles by a double emulsion-solvent evaporation method. For comparison purposes, formulations containing vancomycin were also prepared. Particle morphology, size distribution, encapsulation efficiency, surface charge, thermal behavior, and in vitro release were assessed. All formulations exhibited a spherical morphology, micrometer size, and negative surface charge. From a very early time stage, the released concentrations of daptomycin and vancomycin were higher than the minimal inhibitory concentration and continued so up to 72 hours. Daptomycin presented a sustained release profile with increasing concentrations of the drug being released up to 72 hours, whereas the release of vancomycin stabilized at 24 hours. The antibacterial activity of the microparticles was assessed by isothermal microcalorimetry against planktonic and sessile MRSA and S. epidermidis. Regarding planktonic bacteria, daptomycin-loaded PCL microparticles presented the highest antibacterial activity against both strains. Isothermal microcalorimetry also revealed that lower concentrations of daptomycin-loaded microparticles were required to completely inhibit the recovery of mature MRSA and S. epidermidis biofilms. Further characterization of the effect of daptomycin-loaded PCL microparticles on mature biofilms was performed by fluorescence in situ hybridization. Fluorescence in situ hybridization showed an important reduction in MRSA biofilm, whereas S. epidermidis biofilms, although inhibited, were not eradicated. In addition, an important attachment of the microparticles to MRSA and S. epidermidis biofilms was observed. Finally, all formulations proved to be biocompatible with both ISO compliant L929 fibroblasts and human MG63 osteoblast-like cells. PMID:26185439

Increased osteoblast and decreased Staphylococcus epidermidis functions on nanophase ZnO and TiO2.

PubMed

Colon, Gabriel; Ward, Brian C; Webster, Thomas J

2006-09-01

Many engineers and surgeons trace implant failure to poor osseointegration (or the bonding of an orthopedic implant to juxtaposed bone) and/or bacteria infection. By using novel nanotopographies, researchers have shown that nanostructured ceramics, carbon fibers, polymers, metals, and composites enhance osteoblast adhesion and calcium/phosphate mineral deposition. However, the function of bacteria on materials with nanostructured surfaces remains largely uninvestigated. This is despite the fact that during normal surgical insertion of an orthopedic implant, bacteria from the patient's own skin and/or mucosa enters the wound site. These bacteria (namely, Staphylococcus epidermidis) irreversibly adhere to an implant surface while various physiological stresses induce alterations in the bacterial growth rate leading to biofilm formation. Because of their integral role in determining the success of orthopedic implants, the objective of this in vitro study was to examine the functions of (i) S. epidermidis and (ii) osteoblasts (or bone-forming cells) on ZnO and titania (TiO(2)), which possess nanostructured compared to microstructured surface features. ZnO is a well-known antimicrobial agent and TiO(2) readily forms on titanium once implanted. Results of this study provided the first evidence of decreased S. epidermidis adhesion on ZnO and TiO(2) with nanostructured when compared with microstructured surface features. Moreover, compared with microphase formulations, results of this study showed increased osteoblast adhesion, alkaline phosphatase activity, and calcium mineral deposition on nanophase ZnO and TiO(2). In this manner, this study suggests that nanophase ZnO and TiO(2) may reduce S. epidermidis adhesion and increase osteoblast functions necessary to promote the efficacy of orthopedic implants.

Endocarditis - children

MedlinePlus

Valve infection - children; Staphylococcus aureus - endocarditis - children; Enterococcus - endocarditis- children; Streptococcus viridians - endocarditis - children; Candida - endocarditis - children; Bacterial endocarditis - children; Infective ...

Comparative analysis of Staphylococcus epidermidis strains utilizing quantitative and cell surface shaving proteomics.

PubMed

Solis, Nestor; Cain, Joel A; Cordwell, Stuart J

2016-01-01

Staphylococcus epidermidis is an opportunistic pathogen that is an emerging risk factor in hospitals worldwide and is often difficult to eradicate as virulent strains produce a protective biofilm matrix. We utilized cell shaving proteomics to profile surface-exposed proteins from two fully genome sequenced S. epidermidis strains: the avirulent, non-biofilm forming ATCC12228 and the virulent, strongly adherent biofilm forming ATCC35984 (RP62A). A false positive control strategy was employed to calculate the probabilities of proteins being truly surface-exposed. A total of 78 surface-exposed proteins were identified, of which only 19 proteins were common to ATCC12228 and RP62A, and which thus represents the core surfaceome. S. epidermidis RP62A displayed additional proteins involved in biofilm formation (cell wall-associated Bhp and intercellular adhesion protein IcaB), surface antigenicity, peptidoglycan biosynthesis and antibiotic resistance. We concurrently profiled whole cell proteomes of the two strains using iTRAQ quantitation and LC-MS/MS. A total of 1610 proteins were confidently identified (representing 64% of the theoretical S. epidermidis proteome). One hundred and ninety one proteins were differentially abundant between strains. Proteins associated with RP62A were clustered into functions including Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR)-mediated defense, sulfate assimilation, antibiotic resistance and biofilm formation. Validation of the sulfate assimilation and cysteine/methionine biosynthesis pathways showed RP62A contained elevated levels (~25% increase) of methionine that are likely linked to biofilm formation. Cell shaving and quantitative proteomics identified proteins associated with a biofilm-forming, virulent strain of S. epidermidis (RP62A). These proteins show RP62A maintains an active CRISPR-mediated defense, as well as heightened antibiotic resistance in comparison to a non-virulent, non-biofilm forming strain. Increased abundances of sulfate assimilation proteins lead to elevated intracellular methionine. Proteins and their exposed peptides identified on the surface of S. epidermidis RP62A may be useful vaccine antigens in clinical settings if administered in at-risk patients prior to surgical implantations. Copyright © 2015 Elsevier B.V. All rights reserved.

(68)Ga-DOTA-Siglec-9 PET/CT imaging of peri-implant tissue responses and staphylococcal infections.

PubMed

Ahtinen, Helena; Kulkova, Julia; Lindholm, Laura; Eerola, Erkki; Hakanen, Antti J; Moritz, Niko; Söderström, Mirva; Saanijoki, Tiina; Jalkanen, Sirpa; Roivainen, Anne; Aro, Hannu T

2014-01-01

Staphylococcus epidermidis (S. epidermidis) has emerged as one of the leading pathogens of biomaterial-related infections. Vascular adhesion protein-1 (VAP-1) is an inflammation-inducible endothelial molecule controlling extravasation of leukocytes. Sialic acid-binding immunoglobulin-like lectin 9 (Siglec-9) is a leukocyte ligand of VAP-1. We hypothesized that (68)Ga-labeled 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid-conjugated Siglec-9 motif containing peptide ((68)Ga-DOTA-Siglec-9) could detect inflammatory response due to S. epidermidis peri-implant infection by positron emission tomography (PET). Thirty Sprague-Dawley rats were randomized into three groups. A sterile catheter was implanted into the medullary canal of the left tibia. In groups 1 and 2, the implantation was followed by peri-implant injection of S. epidermidis or Staphylococcus aureus (S. aureus) with adjunct injections of aqueous sodium morrhuate. In group 3, sterile saline was injected instead of bacteria and no aqueous sodium morrhuate was used. At 2 weeks after operation, (68)Ga-DOTA-Siglec-9 PET coupled with computed tomography (CT) was performed with the measurement of the standardized uptake value (SUV). The presence of the implant-related infection was verified by microbiological analysis, imaging with fluorescence microscope, and histology. The in vivo PET results were verified by ex vivo measurements by gamma counter. In group 3, the tibias with implanted sterile catheters showed an increased local uptake of (68)Ga-DOTA-Siglec-9 compared with the intact contralateral bones (SUVratio +29.5%). (68)Ga-DOTA-Siglec-9 PET detected inflammation induced by S. epidermidis and S. aureus catheter-related bone infections (SUVratio +58.1% and +41.7%, respectively). The tracer uptake was significantly higher in the S. epidermidis group than in group 3 without bacterial inoculation, but the difference between S. epidermidis and S. aureus groups was not statistically significant. The difference between the S. aureus group and group 3 was neither statistically significant. PET/CT imaging with novel (68)Ga-DOTA-Siglec-9 tracer was able to detect inflammatory tissue response induced by catheter implantation and staphylococcal infections.

68Ga-DOTA-Siglec-9 PET/CT imaging of peri-implant tissue responses and staphylococcal infections

PubMed Central

2014-01-01

Background Staphylococcus epidermidis (S. epidermidis) has emerged as one of the leading pathogens of biomaterial-related infections. Vascular adhesion protein-1 (VAP-1) is an inflammation-inducible endothelial molecule controlling extravasation of leukocytes. Sialic acid-binding immunoglobulin-like lectin 9 (Siglec-9) is a leukocyte ligand of VAP-1. We hypothesized that 68Ga-labeled 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid-conjugated Siglec-9 motif containing peptide (68Ga-DOTA-Siglec-9) could detect inflammatory response due to S. epidermidis peri-implant infection by positron emission tomography (PET). Methods Thirty Sprague-Dawley rats were randomized into three groups. A sterile catheter was implanted into the medullary canal of the left tibia. In groups 1 and 2, the implantation was followed by peri-implant injection of S. epidermidis or Staphylococcus aureus (S. aureus) with adjunct injections of aqueous sodium morrhuate. In group 3, sterile saline was injected instead of bacteria and no aqueous sodium morrhuate was used. At 2 weeks after operation, 68Ga-DOTA-Siglec-9 PET coupled with computed tomography (CT) was performed with the measurement of the standardized uptake value (SUV). The presence of the implant-related infection was verified by microbiological analysis, imaging with fluorescence microscope, and histology. The in vivo PET results were verified by ex vivo measurements by gamma counter. Results In group 3, the tibias with implanted sterile catheters showed an increased local uptake of 68Ga-DOTA-Siglec-9 compared with the intact contralateral bones (SUVratio +29.5%). 68Ga-DOTA-Siglec-9 PET detected inflammation induced by S. epidermidis and S. aureus catheter-related bone infections (SUVratio +58.1% and +41.7%, respectively). The tracer uptake was significantly higher in the S. epidermidis group than in group 3 without bacterial inoculation, but the difference between S. epidermidis and S. aureus groups was not statistically significant. The difference between the S. aureus group and group 3 was neither statistically significant. Conclusion PET/CT imaging with novel 68Ga-DOTA-Siglec-9 tracer was able to detect inflammatory tissue response induced by catheter implantation and staphylococcal infections. PMID:25520903

Tetracycline resistance phenotypes and genotypes of coagulase-negative staphylococcal isolates from bubaline mastitis in Egypt.

PubMed

El-Razik, K A Abd; Arafa, A A; Hedia, R H; Ibrahim, E S

2017-06-01

This study was devoted to elucidate the tetracycline resistance of coagulase-negative staphylococci (CNS) derived from normal and subclinical mastitic (SCM) buffaloes' milk in Egypt. A total of 81 milk samples from 46 normal buffalo milk samples and 35 SCM buffalo milk samples at private dairy farms of Egypt were used in this study. CNS were identified using phenotypic and molecular methods (polymerase chain reaction [PCR]). CNS isolates were tested for tetracycline resistance using routine methods and multiplex PCR targeting tetracycline ( tet ) resistance genes followed by sequencing of positive PCR products and phylogenetic analysis. Isolation and identification of 28 (34.5%) CNS from normal and SCM buffaloes' milk, namely, Staphylococcus intermedius (39.2%), Staphylococcus xylosus (25.0%), Staphylococcus epidermidis (10.7%), Staphylococcus hominis (10.7%), and 3.5% to each of Staphylococcus sciuri , Staphylococcus hyicus , Staphylococcus lugdunensis , and Staphylococcus simulans . Using nested PCR, all the 28 CNS isolates revealed positive for 16srRNA gene specific for genus staphylococci and negative for thermonuclease ( nuc ) gene specific for Staphylococcus aureus species. The presence of tetracycline resistance-encoding genes ( tet K, tet L, tet M, and tet O) was detected by multiplex PCR. All isolates were negative for tet L, M, and O genes while 14 (50%) CNS isolates were positive for tet K gene, namely, S. lugdunensis (100%), S. hominis (100%), S. epidermidis (66.6%), S. intermedius (45.4%), and S. xylosus (42.8%). Nucleotide sequencing of tet K gene followed by phylogenetic analysis showed the high homology between our CNS isolates genes of tetracycline resistance with S. aureus isolates including Egyptian ones. This proves the transfer of the tetracycline resistance encoding genes between coagulase-negative and coagulase positive Staphylococcus spp. CNS isolates have distinguishingly high resistance to tetracycline. Abundant tetracycline usage for mastitis treatment leads to the spread of genetic resistance mechanisms inside CNS strains and among all Staphylococcus spp. Consequently, tetracycline is not effective anymore.

Tetracycline resistance phenotypes and genotypes of coagulase-negative staphylococcal isolates from bubaline mastitis in Egypt

PubMed Central

El-Razik, K. A. Abd; Arafa, A. A.; Hedia, R. H.; Ibrahim, E. S.

2017-01-01

Aim:: This study was devoted to elucidate the tetracycline resistance of coagulase-negative staphylococci (CNS) derived from normal and subclinical mastitic (SCM) buffaloes’ milk in Egypt. Materials and Methods: :: A total of 81 milk samples from 46 normal buffalo milk samples and 35 SCM buffalo milk samples at private dairy farms of Egypt were used in this study. CNS were identified using phenotypic and molecular methods (polymerase chain reaction [PCR]). CNS isolates were tested for tetracycline resistance using routine methods and multiplex PCR targeting tetracycline (tet) resistance genes followed by sequencing of positive PCR products and phylogenetic analysis. Results:: Isolation and identification of 28 (34.5%) CNS from normal and SCM buffaloes’ milk, namely, Staphylococcus intermedius (39.2%), Staphylococcus xylosus (25.0%), Staphylococcus epidermidis (10.7%), Staphylococcus hominis (10.7%), and 3.5% to each of Staphylococcus sciuri, Staphylococcus hyicus, Staphylococcus lugdunensis, and Staphylococcus simulans. Using nested PCR, all the 28 CNS isolates revealed positive for 16srRNA gene specific for genus staphylococci and negative for thermonuclease (nuc) gene specific for Staphylococcus aureus species. The presence of tetracycline resistance-encoding genes (tetK, tetL, tetM, and tetO) was detected by multiplex PCR. All isolates were negative for tetL, M, and O genes while 14 (50%) CNS isolates were positive for tetK gene, namely, S. lugdunensis (100%), S. hominis (100%), S. epidermidis (66.6%), S. intermedius (45.4%), and S. xylosus (42.8%). Nucleotide sequencing of tetK gene followed by phylogenetic analysis showed the high homology between our CNS isolates genes of tetracycline resistance with S. aureus isolates including Egyptian ones. This proves the transfer of the tetracycline resistance encoding genes between coagulase-negative and coagulase positive Staphylococcus spp. Conclusion:: CNS isolates have distinguishingly high resistance to tetracycline. Abundant tetracycline usage for mastitis treatment leads to the spread of genetic resistance mechanisms inside CNS strains and among all Staphylococcus spp. Consequently, tetracycline is not effective anymore. PMID:28717325

The study of Bacteriocin of Pseudomonas fluorescens and Citrus limon effects against Propionibacterium acnes and Staphylococcus epidermidis in acne patients

NASA Astrophysics Data System (ADS)

Ahmed, Mais E.

2018-05-01

Research was carried out on the antibacterial effect of (Citrus limon) juice on Acnevulgaris. Samples were obtained from individuals with pimples by swabbing their faces. Natural substances that derive from plants are promising to treat disease cause Acnevulgaris, the study in vitro biological activity of the juice, as well as bacterocin cultivated and fruits was investigated on two strains of bacteria (Propionibacterium acnes, Staphylococcus epidermidis). The new antimicrobial (bacteriocin and Citrus juice) is an ongoing search. This study used juice at different concentrations at (20%, 30%, 40%, 60%, 80% and 100%). The bacteriocin produced from local P. fluorescens isolates from wound infection and majority of isolates were found to produce crude bacteriocin were (P1 and P2) in Pseudomonas agar at 37°C for 24 hrs. Crude bacteriocin and Citrus limon juice against some pathogenic skin bacteria was find to be effective juice Citrus limon aganist S. epidermidis at 100% Concentrations with a range of inhibition zone (18) mm. The isolates of P. fluorescens (P2) was positive as producer of bacteriocin with a wide inhibition growth against gram positive pathogenic bacteria with a range between (10-12) mm.

Dexamethasone diffusion across contact lenses is inhibited by Staphylococcus epidermidis biofilms in vitro.

PubMed

Brothers, Kimberly M; Nau, Amy C; Romanowski, Eric G; Shanks, Robert M Q

2014-10-01

This study was designed to measure the impact of bacterial biofilms on diffusion of an ocular therapeutic through silicone hydrogel bandage lenses in vitro. An assay was designed to study the passage of a commonly used steroid, dexamethasone, through silicone hydrogel soft contact lenses. Diffused dexamethasone was measured using a spectrophotometer over a period of 18 hours and quantified using a standard curve. This assay was performed with control and Staphylococcus epidermidis biofilm-coated contact lenses comprised of lotrafilcon A and methafilcon. Biofilms were formed in brain heart infusion broth supplemented with D-glucose. The presented data validate a simple in vitro model that can be used to measure the penetration of a topical therapeutic through silicone hydrogel soft contact lenses. Using this model, we measured a reduction in dexamethasone diffusion up to 88% through S. epidermidis biofilm-coated silicone hydrogel lenses compared with control lenses. The results of this in vitro study demonstrate that bacterial biofilms impede dexamethasone diffusion through silicone hydrogel contact lenses and warrant future studies regarding the clinical benefit of using ocular therapeutics in the setting of bandage contact lens use for corneal epithelial defects.

Inhibition of Staphylococcus epidermidis Biofilm by Trimethylsilane Plasma Coating

PubMed Central

Ma, Yibao; Jones, John E.; Ritts, Andrew C.; Yu, Qingsong

2012-01-01

Biofilm formation on implantable medical devices is a major impediment to the treatment of nosocomial infections and promotes local progressive tissue destruction. Staphylococcus epidermidis infections are the leading cause of biofilm formation on indwelling devices. Bacteria in biofilms are highly resistant to antibiotic treatment, which in combination with the increasing prevalence of antibiotic resistance among human pathogens further complicates treatment of biofilm-related device infections. We have developed a novel plasma coating technology. Trimethylsilane (TMS) was used as a monomer to coat the surfaces of 316L stainless steel and grade 5 titanium alloy, which are widely used in implantable medical devices. The results of biofilm assays demonstrated that this TMS coating markedly decreased S. epidermidis biofilm formation by inhibiting the attachment of bacterial cells to the TMS-coated surfaces during the early phase of biofilm development. We also discovered that bacterial cells on the TMS-coated surfaces were more susceptible to antibiotic treatment than their counterparts in biofilms on uncoated surfaces. These findings suggested that TMS coating could result in a surface that is resistant to biofilm development and also in a bacterial community that is more sensitive to antibiotic therapy than typical biofilms. PMID:22964248

Controlling the Growth of Staphylococcus epidermidis by Layer-By-Layer Encapsulation.

PubMed

Jonas, Alain M; Glinel, Karine; Behrens, Adam; Anselmo, Aaron C; Langer, Robert S; Jaklenec, Ana

2018-05-16

Commensal skin bacteria such as Staphylococcus epidermidis are currently being considered as possible components in skin-care and skin-health products. However, considering the potentially adverse effects of commensal skin bacteria if left free to proliferate, it is crucial to develop methodologies that are capable of maintaining bacteria viability while controlling their proliferation. Here, we encapsulate S. epidermidis in shells of increasing thickness using layer-by-layer assembly, with either a pair of synthetic polyelectrolytes or a pair of oppositely charged polysaccharides. We study the viability of the cells and their delay of growth depending on the composition of the shell, its thickness, the charge of the last deposited layer, and the degree of aggregation of the bacteria which is varied using different coating procedures-among which is a new scalable process that easily leads to large amounts of nonaggregated bacteria. We demonstrate that the growth of bacteria is not controlled by the mechanical properties of the shell but by the bacteriostatic effect of the polyelectrolyte complex, which depends on the shell thickness and charge of its outmost layer, and involves the diffusion of unpaired amine sites through the shell. The lag times of growth are sufficient to prevent proliferation for daily topical applications.

Dexamethasone diffusion across contact lenses is inhibited by Staphylococcus epidermidis biofilms in vitro

PubMed Central

Brothers, Kimberly M.; Nau, Amy C.; Romanowski, Eric G.; Shanks, Robert M. Q.

2014-01-01

Purpose This study was designed to measure the impact of bacterial biofilms on diffusion of an ocular therapeutic through silicone hydrogel bandage lenses in vitro. Methods An assay was designed to study the passage of a commonly used steroid dexamethasone through the silicone hydrogel soft contact lenses. Diffused dexamethasone was measured using a spectrophotometer over a period of 18 hours and quantified using a standard curve. This assay was performed with control and Staphylococcus epidermidis biofilm-coated contact lenses composed of lotrafilcon A and methafilcon. Biofilms were formed in brain heart infusion broth supplemented with D-glucose. Results The presented data validate a simple in vitro model that can be used to measure penetration of a topical therapeutic through silicone hydrogel soft contact lenses. Using this model we measured a reduction of dexamethasone diffusion by up to 88% through S. epidermidis biofilm-coated silicon hydrogel lenses compared to control lenses. Conclusions The results of this in vitro study demonstrate that bacterial biofilms impede dexamethasone diffusion through silicon hydrogel contact lenses, and warrant future studies regarding the clinical benefit of using ocular therapeutics in the setting of bandage contact lens use for corneal epithelial defects. PMID:25090165

The inhibition of staphylococcus epidermidis biofilm formation by vancomycin-modified titanium alloy and implications for the treatment of periprosthetic infection

PubMed Central

Antoci, Valentin; Adams, Christopher S.; Parvizi, Javad; Davidson, Helen M.; Composto, Russell J.; Freeman, Theresa A.; Wickstrom, Eric; Ducheyne, Paul; Jungkind, Donald; Shapiro, Irving M.; Hickok, Noreen J.

2008-01-01

Peri-prosthetic infections are notoriously difficult to treat as the biomaterial implant is ideal for bacterial adhesion and biofilm formation, resulting in decreased antibiotic sensitivity. Previously, we reported that vancomycin covalently attached to a Ti alloy surface (Vanc-Ti) could prevent bacterial colonization. Herein we examine the effect of this Vanc-Ti surface on Staphylococci epidermidis, a Gram-positive organism prevalent in orthopaedic infections. By direct colony counting and fluorescent visualization of live bacteria, S. epidermidis colonization was significantly inhibited on Vanc-Ti implants. In contrast, the gram negative organism Escherichia coli readily colonized the Vanc-Ti rod, suggesting retention of antibiotic specificity. By histochemical and SEM analysis, Vanc-Ti prevented S. epidermidis biofilm formation, even in the presence of serum. Furthermore, when challenged multiple times with S. epidermidis, Vanc-Ti rods resisted bacterial colonization. Finally, when S. epidermidis was continuously cultured in the presence of Vanc-Ti, the bacteria maintained a Vanc sensitivity equivalent to the parent strain. These findings indicate that antibiotic derivatization of implants can result in a surface that can resist bacterial colonization. This technology holds great promises for the prevention and treatment of periprosthetic infections. PMID:18814909

Evaluation of high-resolution melting curve analysis of ligation-mediated real-time PCR, a rapid method for epidemiological typing of ESKAPE (Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Enterobacter Species) pathogens.

PubMed

Woksepp, Hanna; Ryberg, Anna; Billström, Hanna; Hällgren, Anita; Nilsson, Lennart E; Marklund, Britt-Inger; Olsson-Liljequist, Barbro; Schön, Thomas

2014-12-01

A single-tube method, ligation-mediated real-time PCR high-resolution melt analysis (LMqPCR HRMA), was modified for the rapid typing of Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Enterobacter spp. (ESKAPE) pathogens. A 97% agreement (60/62 isolates) was achieved in comparison to pulsed-field gel electrophoresis (PFGE) results, which indicates that LMqPCR HRMA is a rapid and accurate screening tool for monitoring nosocomial outbreaks. Copyright © 2014, American Society for Microbiology. All Rights Reserved.

Bioprotective potential of bacteriocinogenic Enterococcus gallinarum strains isolated from some Nigerian fermented foods, and of their bacteriocins.

PubMed

Oladipo, Iyabo C; Sanni, Abiodun I; Writachit, Chakraborty; Chakravorty, Somnath; Jana, Sayantan; Rudra, Deep S; Gacchui, Ratan; Swarnakar, Snehasikta

2014-01-01

Enterococcus gallinarum strains isolated from some Nigerian fermented foods were found to produce bacteriocins. The bacteriocins had a broad spectrum of activity against both Gram-positive and negative bacteria. The effects of the bacteriocins and bacteriocinogenic organ- isms on Staphylococcus aureus infections in rats were evaluated. Sprague-Dawley rats were infected with S. aureus MTCC 737 and treated with E. gallinarum T71 and different concentrations of the bacteriocins from E. gallinarum W211 and T71. Staphylococcus aureus infection caused significant upregulation of aspartate aminotransferase and alanine aminotransferase levels in sera of the infected rats. Moreover, gelatin zymography revealed that infected gastric tissues showed elevated matrix metalloproteinase-9 activity. Bacteriocin treatments reduced the MMP-9 activity and inhibited the expressions of both Tumour Necrosis Factor Alpha (TNF-α) and Interleukin-1 Beta (IL-1β) dose dependently, pointing to a potential role of the bacteriocins in attenuating inflammatory responses to Staphylococcus aureus infec- tion. Gastric and GIT damage caused by staphylococcal infection were reduced in the Enterococcus gallinarum T71 and bacteriocin-treated groups also dose dependently. We conclude that these bacteriocins may have useful biomedical applications.

BRIC-21: Global Transcriptome Profiling to Identify Cellular Stress Mechanisms Responsible for Spaceflight-Induced Antibiotic Resistance

NASA Technical Reports Server (NTRS)

Nicholson, Wayne L.; Fajardo-Cavazos, Patricia

2015-01-01

Comparisons of spaceflight stress responses in Bacillus subtilis spores and Staphylococcus epidermidis cells to ground-based controls will be conducted to uncover alterations in their antibiotic susceptibility.

Oral Administration of the Broad-Spectrum Antibiofilm Compound Toremifene Inhibits Candida albicans and Staphylococcus aureus Biofilm Formation In Vivo

PubMed Central

De Cremer, Kaat; Delattin, Nicolas; De Brucker, Katrijn; Peeters, Annelies; Kucharíková, Soña; Gerits, Evelien; Verstraeten, Natalie; Michiels, Jan; Van Dijck, Patrick; Thevissen, Karin

2014-01-01

We here report on the in vitro activity of toremifene to inhibit biofilm formation of different fungal and bacterial pathogens, including Candida albicans, Candida glabrata, Candida dubliniensis, Candida krusei, Pseudomonas aeruginosa, Staphylococcus aureus, and Staphylococcus epidermidis. We validated the in vivo efficacy of orally administered toremifene against C. albicans and S. aureus biofilm formation in a rat subcutaneous catheter model. Combined, our results demonstrate the potential of toremifene as a broad-spectrum oral antibiofilm compound. PMID:25288093

Influence of human ascitic fluid on the in vitro antibacterial activity of moxifloxacin.

PubMed

Miglioli, P A; Cappellari, G; Cavallaro, A; Cardaioli, C; Sossai, P; Fille, M; Allerberger, F

2005-08-01

We investigated the in vitro influence of HAF on the antibacterial activity of moxifloxacin against Escherichia coli ATCC 10798, Escherichia coli K-12, Proteus rettgeri (Sanelli), Staphylococcus aureus ATCC 25923, Staphylococcus aureus NCTC 1808 and Staphylococcus epidermidis ATCC 12228. Human ascitic fluid was obtained from 6 cirrhotic patients by paracentesis. The interaction effect was evaluated by the checkerboard technique. Our results indicate the ability of human ascitic fluid to reduce minimum inhibitory concentrations of moxifloxacin against Gram-negative bacteria, but not against Gram-positives.

Bioguided Fractionation Shows Cassia alata Extract to Inhibit Staphylococcus epidermidis and Pseudomonas aeruginosa Growth and Biofilm Formation

PubMed Central

Saito, Samuel Takashi; Trentin, Danielle da Silva; Macedo, Alexandre José; Pungartnik, Cristina; Gosmann, Grace; Silveira, Jaqueline de Deos; Guecheva, Temenouga Nikolova; Henriques, João Antonio Pêgas; Brendel, Martin

2012-01-01

Plant extracts have a long history to be used in folk medicine. Cassia alata extracts are known to exert antibacterial activity but details on compounds and mechanism of action remain poorly explored. We purified and concentrated the aqueous leaf extract of C. alata by reverse phase-solid phase extraction and screened the resulting CaRP extract for antimicrobial activity. CaRP extract exhibited antimicrobial activity for Pseudomonas aeruginosa, Staphylococcus epidermidis, S. aureus, and Bacillus subtilis. CaRP also inhibited biofilm formation of S. epidermidis and P. aeruginosa. Several bacterial growth-inhibiting compounds were detected when CaRP extract was fractionated by TLC chromatography coupled to bioautography agar overlay technique. HPLC chromatography of CaRP extract yielded 20 subfractions that were tested by bioautography for antimicrobial activity against S. aureus and S. epidermidis. Five bioactive fractions were detected and chemically characterized, using high-resolution mass spectrometry (qTOF-MS/MS). Six compounds from four fractions could be characterized as kaempferol, kaempferol-O-diglucoside, kaempferol-O-glucoside, quercetin-O-glucoside, rhein, and danthron. In the Salmonella/microsome assay CaRP showed weak mutagenicity (MI < 3) only in strain TA98, pointing to a frameshift mutation activity. These results indicate that C. alata leaf extract contains a minimum of 7 compounds with antimicrobial activity and that these together or as single substance are active in preventing formation of bacterial biofilm, indicating potential for therapeutic applications. PMID:22548121

Potential of medicinal plants from the Brazilian semi-arid region (Caatinga) against Staphylococcus epidermidis planktonic and biofilm lifestyles.

PubMed

Trentin, Danielle da Silva; Giordani, Raquel Brandt; Zimmer, Karine Rigon; da Silva, Alexandre Gomes; da Silva, Márcia Vanusa; Correia, Maria Tereza Dos Santos; Baumvol, Israel Jacob Rabin; Macedo, Alexandre José

2011-09-01

Medicinal plants from the Caatinga, a Brazilian xeric shrubland, are used in folk medicine to treat infections. These ethnopharmacological data can contribute to obtaining new antimicrobial/antibiofilm extracts and natural product prototypes for the development of new drugs. The aim of this study was to investigate the antibiofilm and antibacterial activities of 45 aqueous extracts from 24 Caatinga plant species. The effect of aqueous extracts on planktonic cells and on biofilm formation by Staphylococcus epidermidis was studied by the OD(600) absorbance and by the crystal violet assay, respectively. Scanning electron microscopy (SEM) was used to generate comparative images of extract-treated and untreated biofilms. Chromatographic analyses were performed to characterize the active extracts. The in vitro screening, at 0.4 mg/mL and 4.0mg/mL, showed 20 plants effective in preventing biofilm formation and 13 plants able to inhibit planktonic bacterial growth. SEM images demonstrated distinct profiles of bacterial adhesion, matrix production and cell morphology according to different treatments and surfaces. The phytochemical analysis of the selected active extracts indicates the polyphenols, coumarins, steroids and terpenes as possible active compounds. This study describes the first antibiofilm and antibacterial screening of Caatinga plants against S. epidermidis. The evaluation presented in this study confirms several ethnopharmacological reports and can be utilized to identify new antibiofilm and antibacterial products against S. epidermidis from traditional Brazilian medicine. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

Adhesion of Pseudomonas aeruginosa and Staphylococcus epidermidis to silicone-hydrogel contact lenses.

PubMed

Henriques, Mariana; Sousa, Cláudia; Lira, Madalena; Elisabete, M; Oliveira, Real; Oliveira, Rosário; Azeredo, Joana

2005-06-01

The purpose of this study is to compare the adhesion capabilities of the most important etiologic agents of microbial ocular infection to the recently available silicone-hydrogel lenses with those to a conventional hydrogel lens. In vitro static adhesion assays of Pseudomonas aeruginosa 10,145, Staphylococcus epidermidis 9142 (biofilm-positive), and 12,228 (biofilm-negative) to two extended-wear silicone-hydrogel lenses (balafilcon A and lotrafilcon A), a daily wear silicone-hydrogel lens (galyfilcon A) and a conventional hydrogel (etafilcon A) were performed. To interpret the adhesion results, lens surface relative hydrophobicity was assessed by water contact angle measurements. P. aeruginosa and S. epidermidis 9142 exhibited greater adhesion capabilities to the extended wear silicone-hydrogel lenses than to the daily wear silicone- and conventional hydrogel lenses (p < 0.05). No statistical differences were found between the adhesion extent of these strains to galyfilcon A and etafilcon A. The biofilm negative strain of S. epidermidis adhered in larger extents to the silicone-hydrogel lenses than to the conventional hydrogel (p < 0.05), but in much lower amounts than the biofilm-positive strain. The water contact angle measurements revealed that the extended wear silicone-hydrogel lenses are hydrophobic, whereas the daily wear silicone- and conventional hydrogel lenses are hydrophilic. As a result of their hydrophobicity, the extended wear silicone-hydrogel lenses (lotrafilcon A and balafilcon A) may carry higher risk of microbial contamination than both the hydrophilic daily wear silicone-hydrogel lens, galyfilcon A and the conventional hydrogel lens, etafilcon A.

XTT assay for evaluating the effect of alcohols, hydrogen peroxide and benzalkonium chloride on biofilm formation of Staphylococcus epidermidis.

PubMed

Chaieb, Kamel; Zmantar, Tarek; Souiden, Yosra; Mahdouani, Kacem; Bakhrouf, Amina

2011-01-01

To analyze the degree of biofilm formation on three ica-positives Staphylococcus epidermidis as a function of biocides, the medium was supplemented with increasing concentrations of isopropanol, ethanol, and methanol at 0, 1, 4, 6, 8, 10, 12 and 14% (v/v), hydrogen peroxide (0, 0.125, 0.25, 0.5, 1, 2, 3, 4 and 5% v/v) and benzalkonium chloride (0, 0.125, 0.25, 0.5, 1, 2, 3, 4 and 6 μg ml⁻¹). In biocide-free biofilms, the results showed that two strains (S. epidermidis CIP106510 and E24) were strongly biofilm positive displaying a high oxidative activity (1.254 and 0.855, respectively) in comparison with the non-adherent one (S22). In addition biofilm formation was induced with 1% alcohol (isopropanol and ethanol) supplementation. The three studied strains cultured in TSB supplemented with 2% methanol displayed a strong oxidative activity (P=0.008). Moreover wells with 0.125% hydrogen peroxide enhanced increasing oxidative activity of S. epidermidis CIP106510 and S22. A significant induction of biofilm was noted after treatment with 1 μg ml⁻¹ of benzalkonium chloride. This study suggests that some biocides currently used in hospitals are ineffective against nosocomial pathogens growing in biofilms when used at weak concentration and fail to control this reservoir for hospital-acquired infection. Copyright © 2010 Elsevier Ltd. All rights reserved.

Bioguided Fractionation Shows Cassia alata Extract to Inhibit Staphylococcus epidermidis and Pseudomonas aeruginosa Growth and Biofilm Formation.

PubMed

Saito, Samuel Takashi; Trentin, Danielle da Silva; Macedo, Alexandre José; Pungartnik, Cristina; Gosmann, Grace; Silveira, Jaqueline de Deos; Guecheva, Temenouga Nikolova; Henriques, João Antonio Pêgas; Brendel, Martin

2012-01-01

Plant extracts have a long history to be used in folk medicine. Cassia alata extracts are known to exert antibacterial activity but details on compounds and mechanism of action remain poorly explored. We purified and concentrated the aqueous leaf extract of C. alata by reverse phase-solid phase extraction and screened the resulting CaRP extract for antimicrobial activity. CaRP extract exhibited antimicrobial activity for Pseudomonas aeruginosa, Staphylococcus epidermidis, S. aureus, and Bacillus subtilis. CaRP also inhibited biofilm formation of S. epidermidis and P. aeruginosa. Several bacterial growth-inhibiting compounds were detected when CaRP extract was fractionated by TLC chromatography coupled to bioautography agar overlay technique. HPLC chromatography of CaRP extract yielded 20 subfractions that were tested by bioautography for antimicrobial activity against S. aureus and S. epidermidis. Five bioactive fractions were detected and chemically characterized, using high-resolution mass spectrometry (qTOF-MS/MS). Six compounds from four fractions could be characterized as kaempferol, kaempferol-O-diglucoside, kaempferol-O-glucoside, quercetin-O-glucoside, rhein, and danthron. In the Salmonella/microsome assay CaRP showed weak mutagenicity (MI < 3) only in strain TA98, pointing to a frameshift mutation activity. These results indicate that C. alata leaf extract contains a minimum of 7 compounds with antimicrobial activity and that these together or as single substance are active in preventing formation of bacterial biofilm, indicating potential for therapeutic applications.

Color of Cultures of Staphylococcus epidermidis Determined by Spectral Reflectance Colorimetry

PubMed Central

Brown, Richard W.

1966-01-01

Brown, Richard W. (National Animal Disease Laboratory, Ames, Iowa). Color of cultures of Staphylococcus epidermidis determined by spectral reflectance colorimetry. J. Bacteriol. 91:911–918. 1966.—A colorimeter with a reflectance attachment was used to study pigment production by Staphylococcus epidermidis strains grown on a medium containing Trypticase Soy Agar (BBL) and cream. The color of each culture was first characterized by reflectance colorimetry for dominant wavelength, purity, and luminous reflectance (Y) and was then classified visually into 1 of 10 color grades. There was not complete agreement in grading colors by the two methods, inasmuch as cultures that were considered more pigmented in relation to other cultures by the reflectance method were sometimes graded visually as less pigmented, and vice versa. Nevertheless, when the cultures were visually graded as being more pigmented, there was a concomitant increase in the average values of dominant wavelength and purity with a decrease in Y for the cultures in each higher grade. Thus, the nonpigmented cultures had the lowest dominant wavelength and purity values but the highest Y (brightness) values, whereas the most pigmented cultures had the highest dominant wavelength and purity values, but the lowest Y values. These results indicated that the cultures did not produce pigments of different hues (greenish-yellow, yellow, yellowish-orange) each with high, medium, and low degrees of purity and brightness. The value (1 − z), where the chromaticity coordinate z = Z/(X + Y + Z), was found to be proportional to the purity value. An inverse relationship between the tristimulus Z and purity values was also demonstrated. All cultures tested by the reflectance method were also classified according to the type of spectral absorption curve obtained with pigments extracted from the cultures with methanol. A comparison of these methods indicated that determining the type of spectral absorption curve would be better for differentiating strains of S. epidermidis, whereas the use of the reflectance method would be better for determining differences of pigment production within strains. PMID:5932106

Multiplex PCR Assay for Identification of Six Different Staphylococcus spp. and Simultaneous Detection of Methicillin and Mupirocin Resistance

PubMed Central

Campos-Peña, E.; Martín-Nuñez, E.; Pulido-Reyes, G.; Martín-Padrón, J.; Caro-Carrillo, E.; Donate-Correa, J.; Lorenzo-Castrillejo, I.; Alcoba-Flórez, J.; Machín, F.

2014-01-01

We describe a new, efficient, sensitive, and fast single-tube multiple-PCR protocol for the identification of the most clinically significant Staphylococcus spp. and the simultaneous detection of the methicillin and mupirocin resistance loci. The protocol identifies at the species level isolates belonging to S. aureus, S. epidermidis, S. haemolyticus, S. hominis, S. lugdunensis, and S. saprophyticus. PMID:24829244

Whole-genome sequencing of staphylococcus haemolyticus uncovers the extreme plasticity of its genome and the evolution of human-colonizing staphylococcal species.

PubMed

Takeuchi, Fumihiko; Watanabe, Shinya; Baba, Tadashi; Yuzawa, Harumi; Ito, Teruyo; Morimoto, Yuh; Kuroda, Makoto; Cui, Longzhu; Takahashi, Mikio; Ankai, Akiho; Baba, Shin-ichi; Fukui, Shigehiro; Lee, Jean C; Hiramatsu, Keiichi

2005-11-01

Staphylococcus haemolyticus is an opportunistic bacterial pathogen that colonizes human skin and is remarkable for its highly antibiotic-resistant phenotype. We determined the complete genome sequence of S.haemolyticus to better understand its pathogenicity and evolutionary relatedness to the other staphylococcal species. A large proportion of the open reading frames in the genomes of S.haemolyticus, Staphylococcus aureus, and Staphylococcus epidermidis were conserved in their sequence and order on the chromosome. We identified a region of the bacterial chromosome just downstream of the origin of replication that showed little homology among the species but was conserved among strains within a species. This novel region, designated the "oriC environ," likely contributes to the evolution and differentiation of the staphylococcal species, since it was enriched for species-specific nonessential genes that contribute to the biological features of each staphylococcal species. A comparative analysis of the genomes of S.haemolyticus, S.aureus, and S.epidermidis elucidated differences in their biological and genetic characteristics and pathogenic potentials. We identified as many as 82 insertion sequences in the S.haemolyticus chromosome that probably mediated frequent genomic rearrangements, resulting in phenotypic diversification of the strain. Such rearrangements could have brought genomic plasticity to this species and contributed to its acquisition of antibiotic resistance.

Dalbavancin reduces biofilms of methicillin-resistant Staphylococcus aureus (MRSA) and methicillin-resistant Staphylococcus epidermidis (MRSE).

PubMed

Knafl, D; Tobudic, S; Cheng, S C; Bellamy, D R; Thalhammer, F

2017-04-01

Activity of dalbavancin against methicillin-resistant Staphylococcus aureus (MRSA) and methicillin-resistant Staphylococcus epidermidis (MRSE) in biofilm was investigated and the microbicidal biofilm concentrations (MBC) were determined. Biofilms obtained from ten MRSA and ten MRSE bloodstream isolates, collected from patients in the General Hospital of Vienna between 2012 and 2015, were incubated with dalbavancin in trypticase soy broth (TSB) in serial dilution from 0.0625 mg/l to 256 mg/l using a microtiter plate biofilm model. The plates were incubated for 24 h at 37 ° C and 50% humidity. Biofilms were fixed with 2.5% glutaraldehyde and stained with crystal violet. Subsequently the optical density (OD 620 ) was used to measure the MBC, defined as the concentration of dalbavancin leading to a 50% reduction of biofilm. MBC for MRSA was 1 mg/l-4 mg/l (minimal inhibitory concentrations (MIC) 0.0312 mg/l-0.064 mg/l). MBC for MRSE was 2 mg/l-16 mg/l (MIC 0.023 mg/l-0.0625 mg/l). Dalbavancin successfully reduced MRSA and MRSE in biofilms, and therefore provides a promising option for the treatment of biofilm-associated infections.

Prevalence and antimicrobial resistance of Enterococcus spp and Staphylococcus spp isolated from surfaces in a veterinary teaching hospital.

PubMed

Hamilton, Elizabeth; Kaneene, John B; May, Katherine J; Kruger, John M; Schall, William; Beal, Matthew W; Hauptman, Joe G; DeCamp, Charles E

2012-06-15

To determine the prevalence and antimicrobial resistance of enterococci and staphylococci collected from environmental surfaces at a veterinary teaching hospital (VTH). Longitudinal study. Samples collected from surfaces in 5 areas (emergency and critical care, soft tissue and internal medicine, and orthopedic wards; surgery preparation and recovery rooms; and surgery office and operating rooms) of a VTH. Selected surfaces were swabbed every 3 months during the 3-year study period (2007 to 2009). Isolates of enterococci and staphylococci were identified via biochemical tests, and antimicrobial susceptibility was evaluated with a microbroth dilution technique. A subset of isolates was analyzed to assess clonality by use of pulsed-field gel electrophoresis. 430 samples were collected, and isolates of enterococci (n = 75) and staphylococci (110) were identified. Surfaces significantly associated with isolation of Enterococcus spp and Staphylococcus spp included cages and a weight scale. Fourteen Enterococcus spp isolates and 17 Staphylococcus spp isolates were resistant to ≥ 5 antimicrobials. Samples collected from the scale throughout the study suggested an overall increase in antimicrobial resistance of Enterococcus faecium over time. Clonality was detected for E faecium isolates collected from 2 different surfaces on the same day. Although not surprising, the apparent increase in antimicrobial resistance of E faecium was of concern because of the organism's ability to transmit antimicrobial resistance genes to other pathogens. Results reported here may aid in identification of critical control points to help prevent the spread of pathogens in VTHs.

[Prevalence and features of pathogenic bacteria in the department of hematology without bone marrow transplantation in Peking Union Medical College Hospital from 2010 to 2012].

PubMed

Wnag, Lu; Yang, Chen; Zhang, Qian; Han, Bing; Zhuang, Jun-jing; Chen, Miao; Zou, Nong; Li, Jian; Duan, Ming-hui; Zhang, Wei; Zhu, Tie-nan; Xu, Ying; Wang, Shu-jie; Zhou, Dao-bin; Zhao, Yong-qiang; Zhang, Hui; Wang, Peng; Xu, Ying-chun

2014-08-01

To investigate the incidence, pathogens, and clinical features of infection in consecutive cases from 2010 to 2012 in Peking Union Medical College Hospital. The incidence, pathogen, treatment, and outcomes of patients with hematological diseases who had positive findings of bacterium in their samples from 2010 to 2012 were retrospectively analyzed. There were 449 positive samples (5.8%) from 4 890 patients during this period, among which 388 were proved to be with pathogenic bacteria. Samples separated from patients with community-aquired infections accounted for 8.4% of all positive samples. Most community-aquired infections were caused by Gram-negative bacteria (75%), although no multidrug-resistant bacteria was observed. Samples separated from patients with nosocomial infections accounted for 91.6% of all positive samples. Respiratory tract (49.4%) and peripheral blood (32.6%) were the most common samples with positive results. Skin soft tissues (10.4%), and urine (3.7%) were less common samples. Most of the pathogenic bacteria of the nosocomial infections were Gram-negative (66.9%). The most common Gram-negative bacteria included Escherichia coli (13.8%), Pseudomonas aeruginosa (12.1%), and Klebsiella pneumonia (12.1%), while Staphylococcus aureus (10.4%), Enterococcus faecium (7.0%), and Staphylococcus epidermidis (5.1%) were the most common Gram-positive bacteria. Gram-negative bacteria consisted of most of sputum samples and peripheral blood samples. Samples from the surface of skin wound and anal swab were composed largely by Gram-positive bacteria (63.8%). The detection rates of extended-spectrum beta-lactamase-producing Klebsiella pneumonia/Klebsiella oxytoca, Escherichia coli, and Proteus mirabilis were 24.0%, 87.9% and 38.4%, respectively. The resistance to Acinetobacter baumannii was serious. Multidrug-resistant, extensive drug resistant and pan drug resistant A. baumannii acountted for 74% of all A. Baumannii infections. Stenotrophomonas maltophilia showed low resistance to sulfamethoxazole/trimethoprim, levofloxacin and minocycline. Also, 22 methicillin-resistant Staphylococcus aureus and 9 methicillin-resistant Staphylococcus Epidermidis were detected, which were only sensitive to vancomycin, teicoplanin, and linezolid. All patients were treated in the haematology wards and most of them were under agranulocytosis or immunosuppression. Finally, 22 patients reached clinical recovery through anti-infective therapy, whereas 49 patients died. Among those deaths, 42 patients attributed to severe infections and infection-associated complications. Fourteen of all the deaths might be infected with drug-resistance bacteria. There were 61 samples proved to be bacteria colonization. Nonfermenters such as Acinetobacter baumannii and Stenotrophomonas maltophilia made up for a large amount of bacteria colonization. The pathogens of nosocomial infections in the hematology ward are mainly Gram-negative bacteria. The incidences and pathogens vary from different infection sites. Nosocomial infection still has a higher mortality rate. Once nonfermenters are detected positive, the pathogenic or colonial bacteria should be distinguished.

Persistent infection by Staphylococcus epidermidis in endodontic flare-up: a case report.

PubMed

Gonçalves, Simone Helena Ferreira; de Vasconcelos, Rafaela Andrade; Cavalcanti, Bruno das Neves; Camargo, Carlos Henrique Ribeiro

2016-01-01

Endodontic flare-ups are challenging situations and may result from selective growth of specific bacterial species; microbial cultures and antibiograms should be used to allow faster, successful management of refractory lesions. A 47-year-old man reported pain on percussion after uncomplicated retreatment of the maxillary left canine for prosthetic purposes. In the following days, pain dramatically increased, leading to removal of the filling and use of intracanal medication. After many unsuccessful attempts to resolve the problem, a microbial culture of the root canal detected the presence of Staphylococcus epidermidis. An antibiogram determined the best drug combination to control this infection: tetracycline (oxytetracycline hydrochloride, 500 mg orally) plus third-generation cephalosporin (ceftriaxone, 1 g intramuscularly). Once the infection was controlled, the root canal was obturated. There was a reduction in the area of radiolucency, and the patient reported no pain at a 2-year follow-up.

Antibacterial screening of traditional herbal plants and standard antibiotics against some human bacterial pathogens.

PubMed

Awan, Uzma Azeem; Andleeb, Saiqa; Kiyani, Ayesha; Zafar, Atiya; Shafique, Irsa; Riaz, Nazia; Azhar, Muhammad Tehseen; Uddin, Hafeez

2013-11-01

Chloroformic and isoamyl alcohol extracts of Cinnnamomum zylanicum, Cuminum cyminum, Curcuma long Linn, Trachyspermum ammi and selected standard antibiotics were investigated for their in vitro antibacterial activity against six human bacterial pathogens. The antibacterial activity was evaluated and based on the zone of inhibition using agar disc diffusion method. The tested bacterial strains were Streptococcus pyogenes, Staphylococcus epidermidis, Klebsiella pneumonia, Staphylococcus aurues, Serratia marcesnces, and Pseudomonas aeruginosa. Ciprofloxacin showed highly significant action against K. pneumonia and S. epidermidis while Ampicillin and Amoxicillin indicated lowest antibacterial activity against tested pathogens. Among the plants chloroform and isoamyl alcohol extracts of C. cyminum, S. aromaticum and C. long Linn had significant effect against P. aeruginosa, S. marcesnces and S. pyogenes. Comparison of antibacterial activity of medicinal herbs and standard antibiotics was also recorded via activity index. Used medicinal plants have various phytochemicals which reasonably justify their use as antibacterial agent.

Laser Desorption 7.87 eV Postionization Mass Spectrometry of Antibiotics in Staphylococcus epidermidis Bacterial Biofilms

PubMed Central

Gasper, Gerald L.; Carlson, Ross; Akhmetov, Artem; Moore, Jerry F.; Hanley, Luke

2010-01-01

This paper describes the development of laser desorption 7.87 eV vacuum ultraviolet postionization mass spectrometry (LDPI-MS) to detect antibiotics within intact bacterial colony biofilms. As >99% of the molecules ejected by laser desorption are neutrals, vacuum ultraviolet (VUV) photoionization of these neutrals can provide significantly increased signal compared to detection of directly emitted ions. Postionization with VUV radiation from the molecular fluorine laser single photon ionizes laser desorbed neutrals with ionization potentials below the 7.87 eV photon energy. Antibiotics with structures indicative of sub-7.87 eV ionization potentials were examined for their ability to be detected by 7.87 eV LDPI-MS. Tetracycline, sulfadiazine, and novobiocin were successfully detected neat as dried films physisorbed on porous silicon oxide substrates. Tetracycline and sulfadiazine were then detected within intact Staphylococcus epidermidis colony biofilms, the former with LOD in the micromolar concentration range. PMID:18704905

Dipeptide cis-cyclo(Leucyl-Tyrosyl) produced by sponge associated Penicillium sp. F37 inhibits biofilm formation of the pathogenic Staphylococcus epidermidis.

PubMed

Scopel, Marina; Abraham, Wolf-Rainer; Henriques, Amélia T; Macedo, Alexandre J

2013-02-01

Infections associated to microbial biofilms are involved in 80% of human infections and became a challenge concerning public health. Infections related to Staphylococcus epidermidis biofilms are presently commonly associated to medical devices, increasing treatment costs for this type of infection. Alternatives to eliminate this kind of disease have been employed in screening programs using diverse marine-derived fungi source of bioactive compounds capable to combat biofilm formation. In this work was isolated the dipeptide cis-cyclo(Leucyl-Tyrosyl) from a sponge associated Penicillium sp. possessing a remarkable inhibition up to 85% of biofilm formation without interfering with bacterial growth, confirmed by scanning electron microscopy. This is the first demonstration that cis-cyclo(Leucyl-Tyrosyl) is able to specifically inhibit biofilm formation adding another aspect to the broad spectrum of bioactivities of cyclic dipeptides. Copyright © 2012 Elsevier Ltd. All rights reserved.

Coagulase-negative staphylococci as reservoirs of genes facilitating MRSA infection

PubMed Central

Otto, Michael

2013-01-01

Recent research has suggested that Staphylococcus epidermidis is a reservoir of genes that, after horizontal transfer, facilitate the potential of Staphylococcus aureus to colonize, survive during infection, or resist antibiotic treatment, traits that are notably manifest in methicillin-resistant S. aureus (MRSA). S. aureus is a dangerous human pathogen and notorious for acquiring antibiotic resistance. MRSA in particular is one of the most frequent causes of morbidity and death in hospitalized patients. S. aureus is an extremely versatile pathogen with a multitude of mechanisms to cause disease and circumvent immune defenses. In contrast, most other staphylococci, such as S. epidermidis, are commonly benign commensals and only occasionally cause disease. Recent findings highlight the key importance of efforts to better understand how genes of staphylococci other than S. aureus contribute to survival in the human host, how they are transferred to S. aureus, and why this exchange appears to be uni-directional. PMID:23165978

Divergent Isoprenoid Biosynthesis Pathways in Staphylococcus Species Constitute a Drug Target for Treating Infections in Companion Animals

PubMed Central

Cain, Christine L.; Morris, Daniel O.; Rankin, Shelley C.

2016-01-01

ABSTRACT Staphylococcus species are a leading cause of skin and soft tissue infections in humans and animals, and the antibiotics used to treat these infections are often the same. Methicillin- and multidrug-resistant staphylococcal infections are becoming more common in human and veterinary medicine. From a “One Health” perspective, this overlap in antibiotic use and resistance raises concerns over the potential spread of antibiotic resistance genes. Whole-genome sequencing and comparative genomics analysis revealed that Staphylococcus species use divergent pathways to synthesize isoprenoids. Species frequently associated with skin and soft tissue infections in companion animals, including S. schleiferi and S. pseudintermedius, use the nonmevalonate pathway. In contrast, S. aureus, S. epidermidis, and S. lugdunensis use the mevalonate pathway. The antibiotic fosmidomycin, an inhibitor of the nonmevalonate pathway, was effective in killing canine clinical staphylococcal isolates but had no effect on the growth or survival of S. aureus and S. epidermidis. These data identify an essential metabolic pathway in Staphylococcus that differs among members of this genus and suggest that drugs such as fosmidomycin, which targets enzymes in the nonmevalonate pathway, may be an effective treatment for certain staphylococcal infections. IMPORTANCE Drug-resistant Staphylococcus species are a major concern in human and veterinary medicine. There is a need for new antibiotics that exhibit a selective effect in treating infections in companion and livestock animals and that would not be used to treat human bacterial infections. We have identified fosmidomycin as an antibiotic that selectively targets certain Staphylococcus species that are often encountered in skin infections in cats and dogs. These findings expand our understanding of Staphylococcus evolution and may have direct implications for treating staphylococcal infections in veterinary medicine. PMID:27704053

Occurrence of cfr-mediated multiresistance in staphylococci from veal calves and pigs, from humans at the corresponding farms, and from veterinarians and their family members.

PubMed

Cuny, Christiane; Arnold, Phillippe; Hermes, Julia; Eckmanns, Tim; Mehraj, Jaishri; Schoenfelder, Sonja; Ziebuhr, Wilma; Zhao, Qin; Wang, Yang; Feßler, Andrea T; Krause, Gérard; Schwarz, Stefan; Witte, Wolfgang

2017-02-01

This study reports on the emergence of linezolid-resistant coagulase-negative staphylococci (CoNS) containing the multiresistance gene cfr in veal calves and pigs, as well as in humans exposed to these animals. CoNS (Staphylococcus auricularis, Staphylococcus cohnii, Staphylococcus lentus, Staphylococcus kloosii, Staphylococcus sciuri, Staphylococcus simulans), but not Staphylococcus aureus, carrying the gene cfr were detected in samples of 12 out of 52 calves at three farms which had a history of florfenicol use. Nasal swabs from 10 humans living on these farms were negative for cfr-carrying staphylococci. Nasal swabs taken from 142 calves at 16 farms in the same area that did not use florfenicol were also negative for cfr-carrying staphylococci. 14 cfr-carrying CoNS (S. kloosii, S. saprophyticus, S. simulans) were detected in three of eight conventional pig farms investigated. One of 12 humans living on these farms harboured a cfr-carrying S. cohnii. Among the nasal swabs taken from 169 veterinarians from all over Germany, four (2.3%) were positive for cfr-carrying CoNS (three S. epidermidis, one S. saprophyticus), and three (1.1%) of 263 contact persons of this group also harboured cfr-carrying CoNS (one S. epidermidis, two S. saprophyticus). In vitro conjugation of cfr by filter mating to S. aureus 8325-4 was possible for 10 of 34CoNS and the cfr gene was associated with plasmids of 38-40kb. Moreover, a total of 363 humans of a German municipal community were investigated for nasal carriage of cfr-carrying staphylococci to get an idea whether such isolates are disseminated as nasal colonizers in non-hospitalized humans in the community, were all negative. Copyright © 2016 Elsevier B.V. All rights reserved.

Bacterial Coaggregation Among the Most Commonly Isolated Bacteria From Contact Lens Cases.

PubMed

Datta, Ananya; Stapleton, Fiona; Willcox, Mark D P

2017-01-01

To examine the coaggregation and cohesion between the commonly isolated bacteria from contact lens cases. Four or five strains each of commonly isolated bacteria from contact lens cases, Staphylococcus aureus, Staphylococcus epidermidis, Pseudomonas aeruginosa, and Serratia marcescens, were grown, washed, mixed in equal proportions, and allowed to coaggregate for 24 hours. Lactose (0.06 M), sucrose (0.06 M), and pronase (2 mg/mL; 2 hours, 37°C) were used to inhibit coaggregation. Oral bacterial isolates of Actinomyces naeslundii and Streptococcus sanguinis were used as a positive control for coaggregation. Cohesion was performed with the ocular bacteria that demonstrated the highest level of coaggregation. Production of growth-inhibitory substances was measured by growing strains together on agar plates. The oral bacterial pair showed >80% coaggregation. Coaggregation occurred between ocular strains of S. aureus (2/5) or S. epidermidis (2/5) with P. aeruginosa strains (3/5); 42% to 62%. There was only slight coaggregation between staphylococci and S. marcescens. Staphylococcus aureus coaggregated with S. epidermidis. Lactose or sucrose treatment of S. aureus but pronase treatment of P. aeruginosa reversed the coaggregation. There was no cohesion between the ocular isolates. P. aeruginosa was able to stop growth of S. aureus but not vice versa. This study demonstrated for the first time that ocular isolates of P. aeruginosa and S. aureus could coaggregate, probably through lectin-carbohydrate interactions. However, this may not be related to biofilm formation in contact lens cases, as there was no evidence that the coaggregation was associated with cohesion between the strains.

Journal of Special Operations Medicine. Volume 5, Edition 2, Spring 2005

DTIC Science & Technology

2005-01-01

some Gram-positive bacteria.3 Sulconazole has some antibacterial activity against Gram- positive Staphylococcus aureus, Staphylococcus epidermidis...Medicine (JSOM). USSOCOM-SG distributes the JSOM to all our SOF units and our active editorial consultants. We can also email you the JSOM PDF; if you...continually had a very strong pro- gram and have definitely set the standard for NTMs among all the groups, both active and reserve component. This

Evaluation of antibacterial properties of some medicinal plants used in Iran.

PubMed

Bonjar, Shahidi

2004-10-01

Forty-five species of 29 plant families used in the traditional medicine by Iranian people, showed antibacterial activities against one or more of the bacterial species: Bacillus cereus, Bacillus pumilus, Bordetella bronchiseptica, Escherichia coli, Klebsiella pneumoniae, Micrococcus luteus, Pseudomonas aeruginosa, Pseudomonas fluorescens, Serratia marcescens, Staphylococcus aureus and Staphylococcus epidermidis. No plant showed activity against Serratia marcescens; Bordetella bronchiseptica being the most susceptible species. All extracts showed the same activity 18 months later.

Identification, typing, ecology and epidemiology of coagulase negative staphylococci associated with ruminants.

PubMed

Vanderhaeghen, Wannes; Piepers, Sofie; Leroy, Frédéric; Van Coillie, Els; Haesebrouck, Freddy; De Vliegher, Sarne

2015-01-01

Since phenotypic methods to identify coagulase negative staphylococci (CNS) from the milk of ruminants often yield unreliable results, methods for molecular identification based on gene sequencing or fingerprinting techniques have been developed. In addition to culture-based detection of isolates, culture-independent methods may be of interest. On the basis of molecular studies, the five CNS species commonly causing intramammary infections (IMI) are Staphylococcus chromogenes, Staphylococcus epidermidis, Staphylococcus haemolyticus, Staphylococcus simulans and Staphylococcus xylosus. Current knowledge suggests that S. chromogenes is a bovine-adapted species, with most cases of IMI due to this bacterium being opportunistic. S. haemolyticus also appears to be an opportunistic pathogen, but this bacterium occupies a variety of habitats, the importance of which as a source of IMI remains to be elucidated. S. xylosus appears to be a versatile species, but little is known of its epidemiology. S. epidermidis is considered to be a human-adapted species and most cases of IMI appear to arise from human sources, but the organism is capable of residing in other habitats. S. simulans typically causes contagious IMI, but opportunistic cases also occur and the ecology of this bacterium requires further study. Further studies of the ecology and epidemiology of CNS as a cause of IMI in cattle are required, along with careful attention to classification of these bacteria and the diseases they cause. Copyright © 2014 Elsevier Ltd. All rights reserved.

Identification of ABC transporter genes conferring combined pleuromutilin-lincosamide-streptogramin A resistance in bovine methicillin-resistant Staphylococcus aureus and coagulase-negative staphylococci.

PubMed

Wendlandt, Sarah; Kadlec, Kristina; Feßler, Andrea T; Schwarz, Stefan

2015-06-12

The aim of this study was to investigate the genetic basis of combined pleuromutilin-lincosamide-streptogramin A resistance in 26 unrelated methicillin-resistant Staphylococcus aureus (MRSA) and coagulase-negative staphylococci (CoNS) from dairy cows suffering from mastitis. The 26 pleuromutilin-resistant staphylococcal isolates were screened for the presence of the genes vga(A), vga(B), vga(C), vga(E), vga(E) variant, sal(A), vmlR, cfr, lsa(A), lsa(B), lsa(C), and lsa(E) by PCR. None of the 26 isolates carried the genes vga(B), vga(C), vga(E), vga(E) variant, vmlR, cfr, lsa(A), lsa(B), or lsa(C). Two Staphylococcus haemolyticus and single Staphylococcus xylosus, Staphylococcus lentus, and Staphylococcus hominis were vga(A)-positive. Twelve S. aureus, two Staphylococcus warneri, as well as single S. lentus and S. xylosus carried the lsa(E) gene. Moreover, single S. aureus, S. haemolyticus, S. xylosus, and Staphylococcus epidermidis were positive for both genes, vga(A) and lsa(E). The sal(A) gene was found in a single Staphylococcus sciuri. All ABC transporter genes were located in the chromosomal DNA, except for a plasmid-borne vga(A) gene in the S. epidermidis isolate. The genetic environment of the lsa(E)-positive isolates was analyzed using previously described PCR assays. Except for the S. warneri and S. xylosus, all lsa(E)-positive isolates harbored a part of the previously described enterococcal multiresistance gene cluster. This is the first report of the novel lsa(E) gene in the aforementioned bovine CoNS species. This is also the first identification of the sal(A) gene in a S. sciuri from a case of bovine mastitis. Moreover, the sal(A) gene was shown to also confer pleuromutilin resistance. Copyright © 2015 Elsevier B.V. All rights reserved.

Cytotoxic and Antibacterial Angucycline- and Prodigiosin- Analogues from the Deep-Sea Derived Streptomyces sp. SCSIO 11594

PubMed Central

Song, Yongxiang; Liu, Guangfu; Li, Jie; Huang, Hongbo; Zhang, Xing; Zhang, Hua; Ju, Jianhua

2015-01-01

Two new C-glycoside angucyclines, marangucycline A (1) and marangucycline B (2), along with three known compounds, dehydroxyaquayamycin (3), undecylprodigiosin (4) and metacycloprodigiosin (5), have been identified as products of the deep-sea sediment strain Streptomyces sp. SCSIO 11594. New structures were elucidated on the basis of HRESIMS, 1D and 2D NMR analyses and comparisons to previously reported datasets. Compounds 2 and 4 displayed in vitro cytotoxicity against four cancer cell lines A594, CNE2, HepG2, MCF-7 superior to those obtained with cisplatin, the positive control. Notably, compound 2 bearing a keto-sugar displayed significant cytotoxicity against cancer cell lines with IC50 values ranging from 0.24 to 0.56 μM; An IC50 value of 3.67 μM was found when using non-cancerous hepatic cell line HL7702, demonstrating the cancer cell selectivity of 2. Compounds 1–3 were proved to have weak antibacterial activities against Enterococcus faecalis ATCC29212 with an MIC value of 64.0 μg/mL. Moreover, 3 displayed selective antibacterial activity against methicillin-resistant Staphylococcus epidermidis shhs-E1 with an MIC value of 16.0 μg/mL. PMID:25786061

Novel aminohydrazide cross-linked chitosan filled with multi-walled carbon nanotubes as antimicrobial agents.

PubMed

Mohamed, Nadia A; Abd El-Ghany, Nahed A

2018-04-21

Four chemically modified chitosan derivatives 1-4 were designed and synthesized via a series of four reactions; first by reaction with benzaldehyde to protect its amino groups (Derivative 1), second by reaction with epichlorohydrine (Derivative 2), third by reaction with aminobenzhydrazide (Derivative 3), and forth by removing of benzaldehyde to restore the free amino groups on the chitosan (Derivative 4). Two multi-walled carbon nanotube (MWCNT) biocomposites based on Derivative 4 were also prepared. The structure of the prepared derivatives and MWCNT composites was elucidated using elemental analyses, FTIR, XRD, SEM and TEM. The modified chitosan derivatives and MWCNT composites showed better antimicrobial activities than that of chitosan against Enterococcus faecalis, Staphylococcus epidermidis, Escherichia coli, Aspergillus niger, Cryptococcus neoformans and Candida tropicalis as judged by their higher inhibition zone diameters using the agar well diffusion technique. These derivatives and MWCNT composites are more potent against Gram-positive bacteria than against Gram-negative bacteria. The MWCNT composites displayed comparable or even better antimicrobial activities than the reference bactericides or fungicides. Thus, structural modification of chitosan through combination with functionalized moieties and MWCNTs in one system was taken as a way to achieve promising templates for antimicrobial agents and to be appropriate candidates for medical applications. Copyright © 2018 Elsevier B.V. All rights reserved.

Constituents and antimicrobial properties of blue honeysuckle: a novel source for phenolic antioxidants.

PubMed

Palíková, Irena; Heinrich, Jan; Bednár, Petr; Marhol, Petr; Kren, Vladimír; Cvak, Ladislav; Valentová, Katerina; Růzicka, Filip; Holá, Veronika; Kolár, Milan; Simánek, Vilím; Ulrichová, Jitka

2008-12-24

The fruit of Lonicera caerulea L. (blue honeysuckle; Caprifoliaceae) and its phenolic fraction were analyzed for nutrients and micronutrients. The phenolic fraction was prepared from berries percolated with 0.1% H3PO4 and SPE using Sepabeads SP207. The sugar and lipid content was analyzed by HPLC and GC-MS. The total content of anthocyanins was determined using the pH differential absorbance method and aliphatic acids by capillary electrophoresis. MicroLC-MS/MS was used for determination of cyanidin-3-glucoside (the predominant anthocyanin), 3,5-diglucoside, and 3-rutinoside, paeonidin-3-glucoside, 3,5-diglucoside, and 3-rutinoside, delphinidin-3-glucoside and 3-rutinoside, pelargonidin-3-glucoside, 3,5-diglucoside, and 3-rutinoside, quercetin, its 3-glucoside, and 3-rutinoside, epicatechin, protocatechuic, gentisic, ellagic, ferulic, caffeic, chlorogenic, and coumaric acids. The phenolic fraction displayed Folin-Ciocalteu reagent reducing (335 +/- 15 microg of gallic acid equivalent/mg) and DPPH and superoxide scavenging activity (IC50 12.1 +/- 0.1 and 115.5 +/- 6.4 microg/mL) and inhibited rat liver microsome peroxidation (IC50 160 +/- 20 microg/mL). The freeze-dried fruit and its phenolic fraction reduced the biofilm formation and adhesion to the artificial surface of Candida parapsilosis, Staphylococcus epidermidis, Escherichia coli, Enterococcus faecalis, and Streptococcus mutans.

Longitudinal surveillance on antibiogram of important Gram-positive pathogens in Southern China, 2001 to 2015.

PubMed

Xu, Zhenbo; Xie, Jinhong; Peters, Brian M; Li, Bing; Li, Lin; Yu, Guangchao; Shirtliff, Mark E

2017-02-01

A longitudinal surveillance aimed to investigate the antibiogram of three genus of important Gram-positive pathogens in Southern China during 2001-2015. A total of 3849 Staphylococcus, Enterococcus and Streptococcus strains were isolated from Southern China during 2001-2015. Bacteria identification was performed by colony morphology, Gram staining, the API commercial kit and the Vitek 2 automated system. Antimicrobial susceptibility testing was determined by disk diffusion method and MIC method. As sampling site was concerned, 51.4% of Staphylococcus strains were isolated from sputum, whereas urinary tract remained the dominant infection site among Enterococcus and Streptococcus. According to the antimicrobial susceptibility, three genus of important Gram-positive pathogens showed high resistance against erythromycin, tetracycline, ciprofloxacin and clindamycin. Resistance rates to penicillins (penicillin, oxacillin, ampicillin) were high as well, with the exception of E. faecalis and Streptococcus. Overall, resistance rates against methicillin (oxacillin) were 63.2% in S. aureus and 76.2% in coagulase-negative Staphylococcus (CNS), along with continuous increases during the study. VRSA and vancomycin-resistant coagulase-negative Staphylococcus only appeared in 2011-2015. Sight decline was obtained for the vancomycin resistance of E. faecalis, while vancomycin-resistant E. faecium only appeared in 2011-2015, with its intermediate rate decreasing. Significant decrease in penicillin-resistant Streptococcus pneumonia (PRSP) was observed during studied period. Glycopeptide antibiotic remained highly effective to Staphylococcus, Enterococcus and Streptococcus (resistance rates <5%). Despite decline obtained for some antibiotic agents resistance during 2001-2015, antimicrobial resistance among Gram-positive pathogens still remained high in Southern China. This study may aid in the guidance for appropriate therapeutic strategy of infections caused by nosocomial pathogens. Copyright © 2016 Elsevier Ltd. All rights reserved.

Antibacterial Activity of Ethanolic Extract of Cinnamon Bark, Honey, and Their Combination Effects against Acne-Causing Bacteria

PubMed Central

Julianti, Elin; Rajah, Kasturi K.; Fidrianny, Irda

2017-01-01

Propionibacterium acnes and Staphylococcus epidermidis are the major skin bacteria that cause the formation of acne. The present study was conducted to investigate antibacterial activity of ethanolic extract of cinnamon bark, honey, and their combination against acne bacteria. The antibacterial activity of extract of cinnamon bark and honey were investigated against P. acnes and S. epidermidis using disc diffusion. Minimum inhibitory concentrations (MICs) and minimum bactericidal concentrations (MBCs) were attained using Clinical and Laboratory Standard Institute (CLSI) methods. The interaction between cinnamon bark extract and honey was determined using a checkerboards method. The results showed that the MICs of cinnamon bark extract and honey against P. acne were 256 µg/mL and 50% v/v, respectively, while those against S. epidermidis were 1024 µg/mL and 50% v/v, respectively. The MBC of cinnamon bark extract against P. acnes and S. epidermidis were more than 2048 µg/mL, whereas the MBC for honey against P. acnes and S. epidermidis were 100%. The combination of cinnamon bark extract and honey against P. acnes and S. epidermidis showed additive activity with a fractional inhibitory concentration index (FICI) value of 0.625. Therefore, the combination of cinnamon bark extract and honey has potential activity against acne-causing bacteria. PMID:28398231

A new rabbit model of implant-related biofilm infection: development and evaluation

NASA Astrophysics Data System (ADS)

Chu, Cheng-Bing; Zeng, Hong; Shen, Ding-Xia; Wang, Hui; Wang, Ji-Fang; Cui, Fu-Zhai

2016-03-01

This study is to establish a rabbit model for human prosthetic joint infection and biofilm formation. Thirty-two healthy adult rabbits were randomly divided into four groups and implanted with stainless steel screws and ultra-high molecular weight polyethylene (UHMWPE) washers in the non-articular surface of the femoral lateral condyle of the right hind knees. The rabbit knee joints were inoculated with 1 mL saline containing 0, 102, 103, 104 CFU of Staphylococcus epidermidis ( S. epidermidis) isolated from the patient with total knee arthroplasty (TKA) infection, respectively. On the 14th postoperative day, the UHMWPE washers from the optimal 103 CFU group were further examined. The SEM examination showed a typical biofilm construction that circular S. epidermidis were embedded in a mucous-like matrix. In addition, the LCSM examination showed that the biofilm consisted of the polysaccharide stained bright green fluorescence and S. epidermidis radiating red fluorescence. Thus, we successfully create a rabbit model for prosthetic joint infection and biofilm formation, which should be valuable for biofilm studies.

In Vitro Assessment of Electric Currents Increasing the Effectiveness of Vancomycin Against Staphylococcus epidermidis Biofilms.

PubMed

Haddad, Peter A; Mah, Thien-Fah; Mussivand, Tofy

2016-08-01

Biofilms are communities of bacteria that can cause infections which are resistant to the immune system and antimicrobial treatments, posing a significant threat for patients with implantable and indwelling medical devices. The purpose of our research was to determine if utilizing specific parameters for electric currents in conjunction with antibiotics could effectively treat a highly resistant biofilm. Our study evaluated the impact of 16 μg/mL of vancomycin with or without 22 or 333 μA of direct electric current (DC) generated by stainless steel electrodes against 24-, 48-, and 72-h-old Staphylococcus epidermidis biofilms formed on titanium coupons. An increase in effectiveness of vancomycin was observed with the combination of 333 μA of electric current against 48-h-old biofilms (P value = 0.01) as well as in combination with 22 μA of electric current against 72-h-old biofilms (P value = 0.04); 333 μA of electric current showed the most significant impact on the effectiveness of vancomycin against S. epidermidis biofilms demonstrating a bioelectric effect previously not observed against this strain of bacteria. © 2015 International Center for Artificial Organs and Transplantation and Wiley Periodicals, Inc.

In vitro evaluation of the antibiotic lock technique (ALT) for the treatment of catheter-related infections caused by staphylococci.

PubMed

Lee, Ji-Young; Ko, Kwan Soo; Peck, Kyong Ran; Oh, Won Sup; Song, Jae-Hoon

2006-06-01

To investigate appropriate antimicrobial agents, the optimal concentration and treatment duration for the antibiotic lock technique (ALT) to treat catheter-related infections caused by Staphylococcus epidermidis and Staphylococcus aureus. We evaluated the bacterial killing activity of vancomycin, teicoplanin, ciprofloxacin, rifampicin, cefazolin, gentamicin, nafcillin and erythromycin against biofilms formed by two strains of S. aureus and two strains of S. epidermidis. The effectiveness of the antibiotic lock was assayed after exposure to antibiotics (1, 5 and 10 mg/mL) for 1, 3, 5, 7, 10 or 14 days using an in vitro model of biofilms on polyurethane film. The biofilms were completely sterile after exposure to vancomycin (5 mg/mL) for 5 days and teicoplanin (5 and 10 mg/mL) for 7 days. Ciprofloxacin and rifampicin (both 5 mg/mL) achieved eradication of the biofilms of both staphylococcal species more rapidly than vancomycin or teicoplanin. Significant biofilm eradication was not achieved with cefazolin, nafcillin, gentamicin and erythromycin at any of the time exposures examined. The data suggest that 5 mg/mL vancomycin, ciprofloxacin or rifampicin can eradicate S. epidermidis and S. aureus biofilms within 5 days. These findings warrant prospective clinical trials for the evaluation of the clinical efficacy of ALT for less than 10 days.

Recombinant human DNase I decreases biofilm and increases antimicrobial susceptibility in staphylococci

PubMed Central

Kaplan, Jeffrey B.; LoVetri, Karen; Cardona, Silvia T.; Madhyastha, Srinivasa; Sadovskaya, Irina; Jabbouri, Saïd; Izano, Era A.

2011-01-01

Extracellular DNA is an adhesive component of staphylococcal biofilms. The aim of this study was to evaluate the antibiofilm activity of recombinant human DNase I (rhDNase) against Staphylococcus aureus and Staphylococcus epidermidis. Using a 96-well microtiter plate crystal violet binding assay, we found that biofilm formation by S. aureus was efficiently inhibited by rhDNase at 1–4 μg l−1, and pre-formed S. aureus biofilms were efficiently detached in 2 min by rhDNase at 1 mg l−1. Pre-treatment of S. aureus biofilms for 10 min with 10 mg l−1 rhDNase increased their sensitivity to biocide killing by 4–5 log units. rhDNase at 10 mg l−1 significantly inhibited biofilm formation by S. epidermidis in medium supplemented with subminimal inhibitory concentrations of antibiotics. We also also found rhDNase significantly increased the survival of S. aureus-infected C. elegans nematodes treated with tobramycin compared to nematodes treated with tobramycin alone. We concluded that rhDNase exhibits potent antibiofilm and antimicrobial-sensitizing activities against S. aureus and S. epidermidis at clinically achievable concentrations. rhDNase, either alone or in combination with antimicrobial agents, may have applications in treating or preventing staphylococcal biofilm-related infections. PMID:22167157

Antibiotic susceptibility among Staphylococcus epidermidis isolated from prosthetic joint infections, with focus on doxycycline.

PubMed

Hamad, Tarza; Hellmark, Bengt; Nilsdotter-Augustinsson, Åsa; Söderquist, Bo

2015-12-01

In recent years, coagulase-negative staphylococci such as Staphylococcus epidermidis have gained importance as nosocomial pathogens, especially in immunocompromised patients and prosthetic joint infections (PJIs). These infections are often long lasting and difficult to treat due to the production of bacterial biofilm and the transformation of the bacteria into a stationary growth phase. Rifampicin is able to penetrate the biofilm, but to reduce the risk of development of rifampicin resistance it should be used in combination with an additional antibiotic. In this study we used Etest to investigate the antimicrobial susceptibility of 134 clinical isolates of S. epidermidis obtained from PJIs to six oral antibiotics: doxycycline, rifampicin, linezolid, fusidic acid, clindamycin, and ciprofloxacin. We also performed synergy testing on doxycycline in combination with each of the remaining antibiotics. Ninety-three (69%) of the 134 isolates were susceptible to doxycycline, 94/134 (70%) to rifampicin, 56/134 (42%) to clindamycin, 25/134 (19%) to ciprofloxacin, 81/134 (60%) to fusidic acid, and 100% to linezolid. Thirty-two (80%) of the 40 isolates not fully susceptible to rifampicin were susceptible to doxycycline. Doxycycline in combination with each of the other investigated antibiotics exerted an additive effect on nearly half of the isolates, with the exception of clindamycin, which displayed an even higher percentage of additive effect (69%). To conclude, as the majority of the S. epidermidis isolates were susceptible to doxycycline, this antimicrobial agent may provide a potential alternative for combination therapy together with rifampicin. © 2015 APMIS. Published by John Wiley & Sons Ltd.

Staphylococcus epidermidis in the human skin microbiome mediates fermentation to inhibit the growth of Propionibacterium acnes: Implications of probiotics in acne vulgaris

PubMed Central

Wang, Yanhan; Kuo, Sherwin; Shu, Muya; Yu, Jinghua; Huang, Stephen; Dai, Ashley; Two, Aimee; Gallo, Richard L.; Huang, Chun-Ming

2014-01-01

Increasing evidence demonstrates that commensal microorganisms in the human skin microbiome help fight pathogens and maintain homeostasis of the microbiome. However, it is unclear how these microorganisms maintain biological balance when one of them overgrows. The overgrowth of Propionibacterium acnes (P. acnes), a commensal skin bacterium, has been associated with the progression of acne vulgaris. Our results demonstrate that skin microorganisms can mediate fermentation of glycerol, which is naturally produced in skin, to enhance their inhibitory effects on P. acnes growth. The skin microorganisms, most of which have been identified as Staphylococcus epidermidis (S. epidermidis), in the microbiome of human fingerprints can ferment glycerol and create inhibition zones to repel a colony of overgrown P. acnes. Succinic acid, one of four short-chain fatty acids (SCFAs) detected in fermented media by nuclear magnetic resonance (NMR) analysis, effectively inhibits the growth of P. acnes in vitro and in vivo. Both intralesional injection and topical application of succinic acid to P. acnes-induced lesions markedly suppress the P. acnes-induced inflammation in mice. We demonstrate for the first time that bacterial members in the skin microbiome can undergo fermentation to rein in the overgrowth of P. acnes. The concept of bacterial interference between P. acnes and S. epidermidis via fermentation can be applied to develop probiotics against acne vulgaris and other skin diseases. In addition, it will open up an entirely new area of study for the biological function of the skin microbiome in promoting human health. PMID:24265031

The use of quaternised chitosan-loaded PMMA to inhibit biofilm formation and downregulate the virulence-associated gene expression of antibiotic-resistant staphylococcus.

PubMed

Tan, Honglue; Peng, Zhaoxiang; Li, Qingtian; Xu, Xiaofen; Guo, Shengrong; Tang, Tingting

2012-01-01

Biomaterial-associated infections remain a serious complication in orthopaedic surgery. Treatments, including the local use of antibiotic-loaded polymethylmethacrylate (PMMA) bone cement, are not always successful because of multiantibiotic-resistant organisms. In this study, we synthesised a new quaternised chitosan derivative (hydroxypropyltrimethyl ammonium chloride chitosan, HACC) that contains a series of substitutions of quaternary ammonium and demonstrated that HACC with a 26% degree of substitution (DS; referred to as 26%HACC) had a strong antibacterial activity and simultaneously good biocompatibility with osteogenic cells. We loaded 26%HACC at 20% by weight into PMMA bone cement to investigate whether HACC in PMMA prevents bacterial biofilm formation on the surface of bone cements. Chitosan-loaded PMMA (at the same weight ratio), gentamicin-loaded PMMA and PMMA with no antibiotic were also investigated and compared. Two clinical isolates, Staphylococcus epidermidis 389 and methicillin-resistant S. epidermidis (MRSE287), and two standard strains, S. epidermidis (ATCC35984) and methicillin-resistant Staphylococcus aureus (ATCC43300), were selected to evaluate the bacterial biofilm formation at 6, 12 and 24 h using the spread plate method, confocal laser scanning microscopy (CLSM) and scanning electron microscopy (SEM). The results showed that 26%HACC-loaded PMMA inhibited biofilm formation on its surface, while the PMMA control and chitosan-loaded PMMA were unable to inhibit biofilm formation. The gentamicin-loaded PMMA decreased the number of viable methicillin-resistant Staphylococcus strains, but its ability to inhibit biofilm formation was lower than 26%HACC-loaded PMMA. Real-time PCR demonstrated that 26%HACC-loaded PMMA markedly downregulated the expression of icaAD, which encodes essential enzymes for polysaccharide intercellular adhesion (PIA) biosynthesis, upregulated the expression level of icaR, which negatively mediates icaAD expression, and also downregulated the expression of MecA, which encodes membrane-bound enzymes known to be penicillin-binding proteins. Our study indicates that 26%HACC-loaded PMMA prevents biofilm formation of Staphylococcus, including antibiotic-resistant strains, on the surface of bone cement, and downregulates the virulence-associated gene expression of antibiotic-resistant staphylococcus, thus providing a promising new strategy for combating implant infections and osteomyelitis. Copyright © 2011 Elsevier Ltd. All rights reserved.

Quantitative and Qualitative Analysis of Bacteria in Er(III) Solution by Thin-Film Magnetopheresis

PubMed Central

Zborowski, Maciej; Tada, Yoko; Malchesky, Paul S.; Hall, Geraldine S.

1993-01-01

Magnetic deposition, quantitation, and identification of bacteria reacting with the paramagnetic trivalent lanthanide ion, Er3+, was evaluated. The magnetic deposition method was dubbed thin-film magnetopheresis. The optimization of the magnetic deposition protocol was accomplished with Escherichia coli as a model organism in 150 mM NaCl and 5 mM ErCl3 solution. Three gram-positive bacteria, Staphylococcus epidermidis, Staphylococcus saprophyticus, and Enterococcus faecalis, and four gram-negative bacteria, E. coli, Pseudomonas aeruginosa, Proteus mirabilis, and Klebsiella pneumoniae, were subsequently investigated. Quantitative analysis consisted of the microscopic cell count and a scattered-light scanning of the magnetically deposited material aided by the computer data acquisition system. Qualitative analysis consisted of Gram stain differentiation and fluorescein isothiocyanate staining in combination with selected antisera against specific types of bacteria on the solid substrate. The magnetic deposition protocol allowed quantitative detection of E. coli down to the concentration of 105 CFU ml-1, significant in clinical diagnosis applications such as urinary tract infections. Er3+ did not interfere with the typical appearance of the Gram-stained bacteria nor with the antigen recognition by the antibody in the immunohistological evaluations. Indirect antiserum-fluorescein isothiocyanate labelling correctly revealed the presence of E. faecalis and P. aeruginosa in the magnetically deposited material obtained from the mixture of these two bacterial species. On average, the reaction of gram-positive organisms was significantly stronger to the magnetic field in the presence of Er3+ than the reaction of gram-negative organisms. The thin-film magnetophoresis offers promise as a rapid method for quantitative and qualitative analysis of bacteria in solutions such as urine or environmental water. Images PMID:16348916

Antibacterial and anticancer activities of acetone extracts from in vitro cultured lichen-forming fungi.

PubMed

Felczykowska, Agnieszka; Pastuszak-Skrzypczak, Alicja; Pawlik, Anna; Bogucka, Krystyna; Herman-Antosiewicz, Anna; Guzow-Krzemińska, Beata

2017-06-07

Lichens that were used in traditional medicine for ages produce numerous secondary metabolites, however our knowledge about biological activities of substances secreted by separated bionts is scarce. The main objectives of this study were to isolate and find optimal conditions for the growth of mycelia from three common lichen-forming fungi, i.e. Caloplaca pusilla, Protoparmeliopsis muralis and Xanthoria parietina and to evaluate antibacterial and antiproliferative activities of their acetone extracts. Agar disc diffusion and broth microdilution methods were used to test antimicrobial activity against six species of bacteria. MTT method, flow cytometry assay and DAPI staining were applied to test antiproliferative activity of selected extracts against MCF-7 (human breast adenocarcinoma), PC-3 (human prostate cancer) and HeLa (human cervix adenocarcinoma) cancer cells. P. muralis strongly inhibited the growth of Gram-positive bacteria, i.e. Bacillus subtilis, Enterococcus faecalis, Staphylococcus aureus and Staphylococcus epidermidis (MICs from 6.67 to 100.00 μg mL -1 ). X. parietina grown on PDA and G-LBM media decreased HeLa or MCF-7 cancer cells viability with IC 50 values of about 8 μg mL -1 , while C. pusilla grown on G-LBM medium showed the highest potency in decreasing MCF-7 (7.29 μg mL -1 ), PC-3 (7.96 μg mL -1 ) and HeLa (6.57 μg mL -1 ) cancer cells viability. We also showed induction of apoptosis in HeLa, PC-3 and MCF-7 cell lines treated with increasing concentrations of C. pusilla extract. We showed that selected acetone extracts demonstrated a strong antimicrobial and anticancer effects that suggests that aposymbiotically cultured lichen-forming fungi can be a source of antibacterial and antiproliferative compounds.

Microbiological and toxicological effects of Perla black bean (Phaseolus vulgaris L.) extracts: in vitro and in vivo studies.

PubMed

Lara-Díaz, Víctor Javier; Gaytán-Ramos, Angel A; Dávalos-Balderas, Alfredo José; Santos-Guzmán, Jesús; Mata-Cárdenas, Benito David; Vargas-Villarreal, Javier; Barbosa-Quintana, Alvaro; Sanson, Misu; López-Reyes, Alberto Gabriel; Moreno-Cuevas, Jorge E

2009-02-01

We investigated the microbiological and toxicological effects of three Perla black bean extracts on the growth and culture of selected pathogenic microorganisms, the toxicity over Vero cell lines and an in vivo rat model. Three different solvents were used to obtain Perla black bean extracts. All three Perla black bean extracts were tested for antibacterial and antiparasitic activity and further analysed for intrinsic cytotoxicity (IC(50)). Methanol Perla black bean extract was used for acute toxicity test in rats, with the up-and-down doping method. All Perla black bean extracts inhibited bacterial growth. Pseudomonas aeruginosa, Proteus vulgaris, Klebsiella oxytoca, Enterococcus faecalis, Staphylococcus aureus, Staphylococcus epidermidis and Listeria monocytogenes showed inhibition, while Escherichia coli and Enterobacter aerogenes did not. Acidified water and acetic acid Perla black bean extract were tested in parasites. The best IC(50) was observed for Giardia lamblia, while higher concentrations were active against Entamoeba histolytica and Trichomonas vaginalis. The Vero cells toxicity levels (IC(50)) for methanol, acidified water and acetic acid Perla black bean extract were [mean +/- S.D. (95% CI)]: 275 +/- 6.2 (267.9-282.0), 390 +/- 4.6 (384.8-395.2) and 209 +/- 3.39 (205.6-212.4) microg/ml, respectively. In vivo acute toxicity assays did not show changes in absolute organ weights, gross and histological examinations of selected tissues or functional tests. The acetic acid and methanol Perla black bean extract proved to exhibit strong antibacterial activity and the acidified water Perla black bean extract exerted parasiticidal effects against Giardia lamblia, Entamoeba hystolitica and Trichomonas vaginalis. The three Perla black bean extracts assayed over Vero cells showed very low toxicity and the methanol Perla black bean extract in vivo did not cause toxicity.

Structural Basis for Nucleotide Binding and Reaction Catalysis in Mevalonate Diphosphate Decarboxylase

DOE Office of Scientific and Technical Information (OSTI.GOV)

Barta, Michael L.; McWhorter, William J.; Miziorko, Henry M.

2012-09-17

Mevalonate diphosphate decarboxylase (MDD) catalyzes the final step of the mevalonate pathway, the Mg{sup 2+}-ATP dependent decarboxylation of mevalonate 5-diphosphate (MVAPP), producing isopentenyl diphosphate (IPP). Synthesis of IPP, an isoprenoid precursor molecule that is a critical intermediate in peptidoglycan and polyisoprenoid biosynthesis, is essential in Gram-positive bacteria (e.g., Staphylococcus, Streptococcus, and Enterococcus spp.), and thus the enzymes of the mevalonate pathway are ideal antimicrobial targets. MDD belongs to the GHMP superfamily of metabolite kinases that have been extensively studied for the past 50 years, yet the crystallization of GHMP kinase ternary complexes has proven to be difficult. To further ourmore » understanding of the catalytic mechanism of GHMP kinases with the purpose of developing broad spectrum antimicrobial agents that target the substrate and nucleotide binding sites, we report the crystal structures of wild-type and mutant (S192A and D283A) ternary complexes of Staphylococcus epidermidis MDD. Comparison of apo, MVAPP-bound, and ternary complex wild-type MDD provides structural information about the mode of substrate binding and the catalytic mechanism. Structural characterization of ternary complexes of catalytically deficient MDD S192A and D283A (k{sub cat} decreased 10{sup 3}- and 10{sup 5}-fold, respectively) provides insight into MDD function. The carboxylate side chain of invariant Asp{sup 283} functions as a catalytic base and is essential for the proper orientation of the MVAPP C3-hydroxyl group within the active site funnel. Several MDD amino acids within the conserved phosphate binding loop ('P-loop') provide key interactions, stabilizing the nucleotide triphosphoryl moiety. The crystal structures presented here provide a useful foundation for structure-based drug design.« less

Comparative assessment of antimicrobial efficacy of different hand sanitizers: An in vitro study.

PubMed

Jain, Vardhaman Mulchand; Karibasappa, Gundabaktha Nagappa; Dodamani, Arun Suresh; Prashanth, Vishwakarma K; Mali, Gaurao Vasant

2016-09-01

To evaluate the antimicrobial efficacy of four different hand sanitizers against Staphylococcus aureus , Staphylococcus epidermidis , Pseudomonas aeruginosa , Escherichia coli , and Enterococcus faecalis as well as to assess and compare the antimicrobial effectiveness among four different hand sanitizers. The present study is an in vitro study to evaluate antimicrobial efficacy of Dettol, Lifebuoy, PureHands, and Sterillium hand sanitizers against clinical isolates of the aforementioned test organisms. The well variant of agar disk diffusion test using Mueller-Hinton agar was used for evaluating the antimicrobial efficacy of hand sanitizers. McFarland 0.5 turbidity standard was taken as reference to adjust the turbidity of bacterial suspensions. Fifty microliters of the hand sanitizer was introduced into each of the 4 wells while the 5 th well incorporated with sterile water served as a control. This was done for all the test organisms and plates were incubated in an incubator for 24 h at 37΀C. After incubation, antimicrobial effectiveness was determined using digital caliper (mm) by measuring the zone of inhibition. The mean diameters of zones of inhibition (in mm) observed in Group A (Sterillium), Group B (PureHands), Group C (Lifebuoy), and Group D (Dettol) were 22 ± 6, 7.5 ± 0.5, 9.5 ± 1.5, and 8 ± 1, respectively. Maximum inhibition was found with Group A against all the tested organisms. Data were statistically analyzed using analysis of variance, followed by post hoc test for group-wise comparisons. The difference in the values of different sanitizers was statistically significant at P < 0.001. Sterillium was the most effective hand sanitizer to maintain the hand hygiene.

Comparative assessment of antimicrobial efficacy of different hand sanitizers: An in vitro study

PubMed Central

Jain, Vardhaman Mulchand; Karibasappa, Gundabaktha Nagappa; Dodamani, Arun Suresh; Prashanth, Vishwakarma K.; Mali, Gaurao Vasant

2016-01-01

Background: To evaluate the antimicrobial efficacy of four different hand sanitizers against Staphylococcus aureus, Staphylococcus epidermidis, Pseudomonas aeruginosa, Escherichia coli, and Enterococcus faecalis as well as to assess and compare the antimicrobial effectiveness among four different hand sanitizers. Materials and Methods: The present study is an in vitro study to evaluate antimicrobial efficacy of Dettol, Lifebuoy, PureHands, and Sterillium hand sanitizers against clinical isolates of the aforementioned test organisms. The well variant of agar disk diffusion test using Mueller-Hinton agar was used for evaluating the antimicrobial efficacy of hand sanitizers. McFarland 0.5 turbidity standard was taken as reference to adjust the turbidity of bacterial suspensions. Fifty microliters of the hand sanitizer was introduced into each of the 4 wells while the 5th well incorporated with sterile water served as a control. This was done for all the test organisms and plates were incubated in an incubator for 24 h at 37΀C. After incubation, antimicrobial effectiveness was determined using digital caliper (mm) by measuring the zone of inhibition. Results: The mean diameters of zones of inhibition (in mm) observed in Group A (Sterillium), Group B (PureHands), Group C (Lifebuoy), and Group D (Dettol) were 22 ± 6, 7.5 ± 0.5, 9.5 ± 1.5, and 8 ± 1, respectively. Maximum inhibition was found with Group A against all the tested organisms. Data were statistically analyzed using analysis of variance, followed by post hoc test for group-wise comparisons. The difference in the values of different sanitizers was statistically significant at P < 0.001. Conclusion: Sterillium was the most effective hand sanitizer to maintain the hand hygiene. PMID:27857768

Microbiology of Explanted Suture Segments from Infected and Noninfected Surgical Patients

PubMed Central

Krepel, Candace J.; Marks, Richard M.; Rossi, Peter J.; Sanger, James; Goldblatt, Matthew; Graham, Mary Beth; Rothenburger, Stephen; Collier, John; Seabrook, Gary R.

2013-01-01

Sutures under selective host/environmental factors can potentiate postoperative surgical site infection (SSI). The present investigation characterized microbial recovery and biofilm formation from explanted absorbable (AB) and nonabsorbable (NAB) sutures from infected and noninfected sites. AB and NAB sutures were harvested from noninfected (70.9%) and infected (29.1%) sites in 158 patients. At explantation, devices were sonicated and processed for qualitative/quantitative bacteriology; selective sutures were processed for scanning electron microscopy (SEM). Bacteria were recovered from 85 (53.8%) explanted sites; 39 sites were noninfected, and 46 were infected. Suture recovery ranged from 11.1 to 574.6 days postinsertion. A significant difference in mean microbial recovery between noninfected (1.2 isolates) and infected (2.7 isolates) devices (P < 0.05) was noted. Staphylococcus epidermidis, Staphylococcus aureus, coagulase-negative staphylococci (CNS), Peptostreptococcus spp., Bacteroides fragilis, Escherichia coli, Enterococcus spp., Pseudomonas aeruginosa, and Serratia spp. were recovered from infected devices, while commensal skin flora was recovered from noninfected devices. No significant difference in quantitative microbial recovery between infected monofilament and multifilament sutures was noted. Biofilm was present in 100% and 66.6% of infected and noninfected devices, respectively (P < 0.042). We conclude that both monofilament and braided sutures provide a hospitable surface for microbial adherence: (i) a significant difference in microbial recovery from infected and noninfected sutures was noted, (ii) infected sutures harbored a mixed flora, including multidrug-resistant health care-associated pathogens, and (iii) a significant difference in the presence or absence of a biofilm in infected versus noninfected explanted devices was noted. Further studies to document the benefit of focused risk reduction strategies to minimize suture contamination and biofilm formation postimplantation are warranted. PMID:23175247

Automated detection and quantitation of bacterial RNA by using electrical microarrays.

PubMed

Elsholz, B; Wörl, R; Blohm, L; Albers, J; Feucht, H; Grunwald, T; Jürgen, B; Schweder, T; Hintsche, Rainer

2006-07-15

Low-density electrical 16S rRNA specific oligonucleotide microarrays and an automated analysis system have been developed for the identification and quantitation of pathogens. The pathogens are Escherichia coli, Pseudomonas aeruginosa, Enterococcus faecalis, Staphylococcus aureus, and Staphylococcus epidermidis, which are typically involved in urinary tract infections. Interdigitated gold array electrodes (IDA-electrodes), which have structures in the nanometer range, have been used for very sensitive analysis. Thiol-modified oligonucleotides are immobilized on the gold IDA as capture probes. They mediate the specific recognition of the target 16S rRNA by hybridization. Additionally three unlabeled oligonucleotides are hybridized in close proximity to the capturing site. They are supporting molecules, because they improve the RNA hybridization at the capturing site. A biotin labeled detector oligonucleotide is also allowed to hybridize to the captured RNA sequence. The biotin labels enable the binding of avidin alkaline phophatase conjugates. The phosphatase liberates the electrochemical mediator p-aminophenol from its electrically inactive phosphate derivative. The electrical signals were generated by amperometric redox cycling and detected by a unique multipotentiostat. The read out signals of the microarray are position specific current and change over time in proportion to the analyte concentration. If two additional biotins are introduced into the affinity binding complex via the supporting oligonucleotides, the sensitivity of the assays increase more than 60%. The limit of detection of Escherichia coli total RNA has been determined to be 0.5 ng/microL. The control of fluidics for variable assay formats as well as the multichannel electrical read out and data handling have all been fully automated. The fast and easy procedure does not require any amplification of the targeted nucleic acids by PCR.

In vitro and in vivo activities of SCE-2787, a new parenteral cephalosporin with a broad antibacterial spectrum.

PubMed Central

Iwahi, T; Okonogi, K; Yamazaki, T; Shiki, S; Kondo, M; Miyake, A; Imada, A

1992-01-01

SCE-2787, a new cephalosporin having a condensed azolium moiety in the 3 position and an aminothiadiazolyl group in the 7 beta side chain, was evaluated for its in vitro and in vivo activities in comparison with those of ceftazidime, flomoxef, cefpirome, and E1040. Against methicillin-susceptible strains of Staphylococcus aureus and Staphylococcus epidermidis, SCE-2787 was more active than ceftazidime and E1040 and was as active as flomoxef and cefpirome, with MICs for 90% of strains tested (MIC90s) being 1.56 micrograms/ml or less. SCE-2787 was also active against Pseudomonas aeruginosa, for which the MIC90 was 6.25 micrograms/ml, which was lower than that of cefpirome and comparable to that of ceftazidime. SCE-2787 was marginally active against methicillin-resistant strains of staphylococci and Enterococcus faecalis, although its MIC90s were the lowest among those of the antibiotics tested. The activities of SCE-2787 against Streptococcus species, most members of the family Enterobacteriaceae, and Haemophilus influenzae exceeded those of ceftazidime and flomoxef and were comparable to those of cefpirome. Furthermore, MIC90s of SCE-2787 were significantly lower than those of ceftazidime for ceftazidime-resistant isolates of Citrobacter freundii and Enterobacter cloacae. SCE-2787 was resistant to hydrolysis by various types of beta-lactamases, including the Bush group 1 beta-lactamases, and had low affinities for these enzymes, with Km or Ki values of greater than 100 microM. The in vitro activity of SCE-2787 was reflected in its efficacy in mouse protection tests. Thus, SCE-2787 appears to be a promising cephalosporin that should be further evaluated in clinical trials. PMID:1510428

Dry reagent dipstick test combined with 23S rRNA PCR for molecular diagnosis of bacterial infection in arthroplasty.

PubMed

Kalogianni, Despina P; Goura, Sophia; Aletras, Alexios J; Christopoulos, Theodore K; Chanos, Michalis G; Christofidou, Myrto; Skoutelis, Athanasios; Ioannou, Penelope C; Panagiotopoulos, Elias

2007-02-15

Periprosthetic joint infections present a challenging problem in orthopaedics. Conventional methods for detection of arthroplasty infections rely on bacterial culture of synovial fluid aspirates. During recent years, however, molecular tests that are based on DNA amplification by the polymerase chain reaction (PCR), followed by electrophoretic analysis of the products, have been introduced. We report a simple and inexpensive assay that allows visual detection and confirmation of the PCR-amplified sequences by hybridization within minutes. The assay is performed in a dry reagent dipstick format (strip) and does not require special instrumentation. Universal primers are used for PCR of the 23S ribosomal RNA (rRNA) gene. The biotinylated amplification product is hybridized with dA-tailed probes that are specific for six pathogens commonly involved in periprosthetic joint infections. The mixture is applied to the strip, which is then immersed in the appropriate buffer. The buffer migrates along the strip by capillary action and rehydrates gold nanoparticles with oligo(dT) strands attached to their surface. The nanoparticles bind to the target DNA through hybridization, and the hybrids are captured by immobilized streptavidin at the test zone of the strip, producing a characteristic red line. Unbound nanoparticles are captured by immobilized oligo(dT) strands at the control zone of the strip, generating a second line. The dipstick test was applied to the detection of Escherichia coli, Staphylococcus aureus, Staphylococcus epidermidis, Streptococcus pneumoniae, Enterococcus faesium, and Haemophilus influenza. Twelve samples of synovial fluids from patients were analyzed for the detection and identification of the infection caused by the six pathogens. The results were compared with bacterial cultures.

Whole-Genome Sequencing of Staphylococcus haemolyticus Uncovers the Extreme Plasticity of Its Genome and the Evolution of Human-Colonizing Staphylococcal Species

PubMed Central

Takeuchi, Fumihiko; Watanabe, Shinya; Baba, Tadashi; Yuzawa, Harumi; Ito, Teruyo; Morimoto, Yuh; Kuroda, Makoto; Cui, Longzhu; Takahashi, Mikio; Ankai, Akiho; Baba, Shin-ichi; Fukui, Shigehiro; Lee, Jean C.; Hiramatsu, Keiichi

2005-01-01

Staphylococcus haemolyticus is an opportunistic bacterial pathogen that colonizes human skin and is remarkable for its highly antibiotic-resistant phenotype. We determined the complete genome sequence of S.haemolyticus to better understand its pathogenicity and evolutionary relatedness to the other staphylococcal species. A large proportion of the open reading frames in the genomes of S.haemolyticus, Staphylococcus aureus, and Staphylococcus epidermidis were conserved in their sequence and order on the chromosome. We identified a region of the bacterial chromosome just downstream of the origin of replication that showed little homology among the species but was conserved among strains within a species. This novel region, designated the “oriC environ,” likely contributes to the evolution and differentiation of the staphylococcal species, since it was enriched for species-specific nonessential genes that contribute to the biological features of each staphylococcal species. A comparative analysis of the genomes of S.haemolyticus, S.aureus, and S.epidermidis elucidated differences in their biological and genetic characteristics and pathogenic potentials. We identified as many as 82 insertion sequences in the S.haemolyticus chromosome that probably mediated frequent genomic rearrangements, resulting in phenotypic diversification of the strain. Such rearrangements could have brought genomic plasticity to this species and contributed to its acquisition of antibiotic resistance. PMID:16237012

Phenol-Soluble Modulin Toxins of Staphylococcus haemolyticus

PubMed Central

Da, Fei; Joo, Hwang-Soo; Cheung, Gordon Y. C.; Villaruz, Amer E.; Rohde, Holger; Luo, Xiaoxing; Otto, Michael

2017-01-01

Coagulase-negative staphylococci (CoNS) are important nosocomial pathogens and the leading cause of sepsis. The second most frequently implicated species, after Staphylococcus epidermidis, is Staphylococcus haemolyticus. However, we have a significant lack of knowledge about what causes virulence of S. haemolyticus, as virulence factors of this pathogen have remained virtually unexplored. In contrast to the aggressive pathogen Staphylococcus aureus, toxin production has traditionally not been associated with CoNS. Recent findings have suggested that phenol-soluble modulins (PSMs), amphipathic peptide toxins with broad cytolytic activity, are widespread in staphylococci, but there has been no systematic assessment of PSM production in CoNS other than S. epidermidis. Here, we identified, purified, and characterized PSMs of S. haemolyticus. We found three PSMs of the β-type, which correspond to peptides that before were described to have anti-gonococcal activity. We also detected an α-type PSM that has not previously been described. Furthermore, we confirmed that S. haemolyticus does not produce a δ-toxin, as results from genome sequencing had indicated. All four S. haemolyticus PSMs had strong pro-inflammatory activity, promoting neutrophil chemotaxis. Notably, we identified in particular the novel α-type PSM, S. haemolyticus PSMα, as a potent hemolysin and leukocidin. For the first time, our study describes toxins of this important staphylococcal pathogen with the potential to have a significant impact on virulence during blood infection and sepsis. PMID:28596942

Phenol-Soluble Modulin Toxins of Staphylococcus haemolyticus.

PubMed

Da, Fei; Joo, Hwang-Soo; Cheung, Gordon Y C; Villaruz, Amer E; Rohde, Holger; Luo, Xiaoxing; Otto, Michael

2017-01-01

Coagulase-negative staphylococci (CoNS) are important nosocomial pathogens and the leading cause of sepsis. The second most frequently implicated species, after Staphylococcus epidermidis , is Staphylococcus haemolyticus . However, we have a significant lack of knowledge about what causes virulence of S. haemolyticus , as virulence factors of this pathogen have remained virtually unexplored. In contrast to the aggressive pathogen Staphylococcus aureus , toxin production has traditionally not been associated with CoNS. Recent findings have suggested that phenol-soluble modulins (PSMs), amphipathic peptide toxins with broad cytolytic activity, are widespread in staphylococci, but there has been no systematic assessment of PSM production in CoNS other than S. epidermidis . Here, we identified, purified, and characterized PSMs of S. haemolyticus . We found three PSMs of the β-type, which correspond to peptides that before were described to have anti-gonococcal activity. We also detected an α-type PSM that has not previously been described. Furthermore, we confirmed that S. haemolyticus does not produce a δ-toxin, as results from genome sequencing had indicated. All four S. haemolyticus PSMs had strong pro-inflammatory activity, promoting neutrophil chemotaxis. Notably, we identified in particular the novel α-type PSM, S. haemolyticus PSMα, as a potent hemolysin and leukocidin. For the first time, our study describes toxins of this important staphylococcal pathogen with the potential to have a significant impact on virulence during blood infection and sepsis.

Cellular pharmacodynamics of the novel biaryloxazolidinone radezolid: studies with infected phagocytic and nonphagocytic cells, using Staphylococcus aureus, Staphylococcus epidermidis, Listeria monocytogenes, and Legionella pneumophila.

PubMed

Lemaire, Sandrine; Kosowska-Shick, Klaudia; Appelbaum, Peter C; Verween, Gunther; Tulkens, Paul M; Van Bambeke, Françoise

2010-06-01

Radezolid is a novel biaryloxazolidinone in clinical development which shows improved activity, including against linezolid-resistant strains. In a companion paper (29), we showed that radezolid accumulates about 11-fold in phagocytic cells, with approximately 60% of the drug localized in the cytosol and approximately 40% in the lysosomes of the cells. The present study examines its activity against (i) bacteria infecting human THP-1 macrophages and located in different subcellular compartments (Listeria monocytogenes, cytosol; Legionella pneumophila, vacuoles; Staphylococcus aureus and Staphylococcus epidermidis, mainly phagolysosomal), (ii) strains of S. aureus with clinically relevant mechanisms of resistance, and (iii) isogenic linezolid-susceptible and -resistant S. aureus strains infecting a series of phagocytic and nonphagocytic cells. Radezolid accumulated to similar levels ( approximately 10-fold) in all cell types (human keratinocytes, endothelial cells, bronchial epithelial cells, osteoblasts, macrophages, and rat embryo fibroblasts). At equivalent weight concentrations, radezolid proved consistently 10-fold more potent than linezolid in all these models, irrespective of the bacterial species and resistance phenotype or of the cell type infected. This results from its higher intrinsic activity and higher cellular accumulation. Time kill curves showed that radezolid's activity was more rapid than that of linezolid both in broth and in infected macrophages. These data suggest the potential interest of radezolid for recurrent or persistent infections where intracellular foci play a determinant role.

Chemical constituents of Helichrysum italicum (Roth) G. Don essential oil and their antimicrobial activity against Gram-positive and Gram-negative bacteria, filamentous fungi and Candida albicans.

PubMed

Djihane, Bouzid; Wafa, Nouioua; Elkhamssa, Soltani; Pedro, De Haro Juan; Maria, Angeles Esteban; Mohamed Mihoub, Zerroug

2017-07-01

The aerial parts of Helichrysum italicum (Roth) G. Don were subjected to hydrodistillation to obtain essential oils which had been analyzed by gas chromatography and gas chromatography coupled with mass spectrometry and tested for antimicrobial activity against 12 bacteria, two yeasts and four fungi by agar diffusion method. The essential oil yielded 0.44% (v/w) and 67 compounds accounting for 99.24% of the oil were identified with a high content of oxygenated sesquiterpenes (61.42%). The most oxygenated sesquiterpene compounds were α-Cedrene (13.61%), α-Curcumene (11.41%), Geranyl acetate (10.05%), Limonene (6.07%), Nerol (5.04%), Neryl acetate (4.91%) and α-Pinene (3.78%). The antimicrobial activity of the essential oil was assayed by using the disk diffusion method on Escherichia coli ATCC 25922, Staphylococcus aureus ATCC 6538, Micrococcus luteus ATCC 4698, Klebsiella pneumonia ATCC 4352, Enterococcus cereus ATCC 2035, Bacillus cereus ATCC 10876, Staphylococcus epidermidis ATCC 12228, Bacillus subtilis ATCC 9372, Pseudomonas aeruginosa ATCC 27853, Enterococcus faecalis ATCC 49452, Proteus mirabilis ATCC 35659, Listeria monocytogenes ATCC 15313 and yeasts Candida albicans ATCC 10231, Saccharomyces cerevisiae ATCC 9763 and fungi, Fusarium solani var. coeruleum , Aspergillus niger , Alternaria alternata , Ascochyta rabiei . H. italicum inhibited the growth of all the tested microorganisms except three bacteria, E. coli ATCC 25922, K. pneumonia ATCC 4352 and L. monocytogenes ATCC 15313. The most sensitive bacterium was E. cereus ATCC 2035 with minimum inhibitory and bactericidal concentrations of 0.79 μg ml -1 . A minimum fungistatic and fungicide concentration of 6.325 μg ml -1 and 12.65 μg ml -1 respectively was obtained with C. albicans ATCC 10231 and S. cerevisiae ATCC 9763. However the four fungi were more resistant with fungistatic minimum concentration ranging from 6.325 μg ml -1 to 50.6 μg ml -1 and a fungicide minimum concentration of 50.6 μg ml -1 . This antimicrobial activity could be attributed to the essential oil chemical composition. Thus this study represents a first step in the study of the chemical composition of H. italicum (Roth) G. Don collected from north Algeria and its antimicrobial properties.

Comparison of Biofilm Formation Capacities of Two Clinical Isolates of Staphylococcus Epidermidis with and without icaA and icaD Genes on Intraocular Lenses.

PubMed

Kıvanç, Sertaç Argun; Kıvanç, Merih; Kılıç, Volkan; Güllülü, Gülay; Özmen, Ahmet Tuncer

2017-04-01

To compare biofilm formations of two Staphylococcus epidermidis (S. epidermidis) isolates with known biofilm formation capacities on four different intraocular lenses (IOL) that have not been studied before. Two isolates obtained from ocular surfaces and identified in previous studies and stored at -86 °C in 15% glycerol in the microbiology laboratory of the Anadolu University Department of Biology were purified and used in the study. The isolates were S. epidermidis KA 15.8 (ICA+), a known biofilm producer isolate positive for icaA, icaD and bap genes, and S. epidermidis KA 14.5 (ICA-), known as a non-biofilm producer isolate negative for icaA, icaD and bap genes. The biofilm formation capacities of the 2 isolates on 4 different IOLs were compared. Two of the IOLs were acrylic (UD613 [IOL A], Turkey; SA60AT [IOL B], USA), and the other two were polymethyl methacrylate (PMMA) (B60130C [IOL C], India; B55125C [IOL D], India). Bacterial enumeration and optical density measurements were done from biofilms that formed on the IOLs. Biofilms were imaged using scanning electron microscopy. Mean bacterial counts on the IOLs were 7.1±0.4 log 10 CFU/mL with the ICA+ isolate, and 6.7±0.8 log 10 CFU/mL with the ICA- isolate; there were no statistically significant differences. Biofilm formation was lower with acrylic lenses than PMMA lenses with both isolates (p=0.009 and p=0.013). The highest biofilm production was obtained on IOL C (PMMA) (p<0.001) and the lowest was obtained on IOL A (hydrophilic acrylic) (p<0.001). Bacterial counts after biofilm formation were lower on acrylic lenses, especially hydrophilic acrylic with hydrophobic properties. Further animal and in vivo studies are required to support the findings of this study.

Comparison of Biofilm Formation Capacities of Two Clinical Isolates of Staphylococcus Epidermidis with and without icaA and icaD Genes on Intraocular Lenses

PubMed Central

Kıvanç, Sertaç Argun; Kıvanç, Merih; Kılıç, Volkan; Güllülü, Gülay; Özmen, Ahmet Tuncer

2017-01-01

Objectives: To compare biofilm formations of two Staphylococcus epidermidis (S. epidermidis) isolates with known biofilm formation capacities on four different intraocular lenses (IOL) that have not been studied before. Materials and Methods: Two isolates obtained from ocular surfaces and identified in previous studies and stored at -86 °C in 15% glycerol in the microbiology laboratory of the Anadolu University Department of Biology were purified and used in the study. The isolates were S. epidermidis KA 15.8 (ICA+), a known biofilm producer isolate positive for icaA, icaD and bap genes, and S. epidermidis KA 14.5 (ICA-), known as a non-biofilm producer isolate negative for icaA, icaD and bap genes. The biofilm formation capacities of the 2 isolates on 4 different IOLs were compared. Two of the IOLs were acrylic (UD613 [IOL A], Turkey; SA60AT [IOL B], USA), and the other two were polymethyl methacrylate (PMMA) (B60130C [IOL C], India; B55125C [IOL D], India). Bacterial enumeration and optical density measurements were done from biofilms that formed on the IOLs. Biofilms were imaged using scanning electron microscopy. Results: Mean bacterial counts on the IOLs were 7.1±0.4 log10 CFU/mL with the ICA+ isolate, and 6.7±0.8 log10 CFU/mL with the ICA- isolate; there were no statistically significant differences. Biofilm formation was lower with acrylic lenses than PMMA lenses with both isolates (p=0.009 and p=0.013). The highest biofilm production was obtained on IOL C (PMMA) (p<0.001) and the lowest was obtained on IOL A (hydrophilic acrylic) (p<0.001). Conclusion: Bacterial counts after biofilm formation were lower on acrylic lenses, especially hydrophilic acrylic with hydrophobic properties. Further animal and in vivo studies are required to support the findings of this study. PMID:28405479

Antimicrobial photodynamic therapy-a promising treatment for prosthetic joint infections.

PubMed

Briggs, Timothy; Blunn, Gordon; Hislop, Simon; Ramalhete, Rita; Bagley, Caroline; McKenna, David; Coathup, Melanie

2018-04-01

Periprosthetic joint infection (PJI) is associated with high patient morbidity and a large financial cost. This study investigated Photodynamic Therapy (PDT) as a means of eradicating bacteria that cause PJI, using a laser with a 665-nm wavelength and methylene blue (MB) as the photosensitizer. The effectiveness of MB concentration on the growth inhibition of methicillin-sensitive Staphylococcus aureus (MSSA), methicillin-resistant Staphylococcus aureus (MRSA), Staphylococcus epidermidis, Pseudomonas aeruginosa and Acinetobacter baumannii was investigated. The effect of laser dose was also investigated and the optimized PDT method was used to investigate its bactericidal effect on species within planktonic culture and following the formation of a biofilm on polished titanium and hydroxyapatite coated titanium discs. Results showed that Staphylococci were eradicated at the lowest concentration of 0.1 mM methylene blue (MB). With P. aeruginosa and A. baumannii, increasing the MB concentration improved the bactericidal effect. When the laser dose was increased, results showed that the higher the power of the laser the more bacteria were eradicated with a laser power ≥ 35 J/cm 2 and an irradiance of 35 mW/cm 2 , eradicating all S. epidermidis. The optimized PDT method had a significant bactericidal effect against planktonic MRSA and S. epidermidis compared to MB alone, laser alone, or control (no treatment). When biofilms were formed, PDT treatment had a significantly higher bactericidal effect than MB alone and laser alone for all species of bacteria investigated on the polished disc surfaces. P. aeruginosa grown in a biofilm was shown to be less sensitive to PDT when compared to Staphylococci, and a HA-coated surface reduced the effectiveness of PDT. This study demonstrated that PDT is effective for killing bacteria that cause PJI.

Biopolymers production with carbon source from the wastes of a beer brewery industry

NASA Astrophysics Data System (ADS)

Wong, Phoeby Ai Ling

The main purpose of this study was to assess the potential and feasibility of malt wastes, and other food wastes, such as soy wastes, ice-cream wastes, confectionery wastes, vinegar wastes, milk waste and sesame oil, in the induction of biosynthesis of PHA, in the cellular assembly of novel PHA with improved physical and chemical properties, and in the reduction of the cost of PHA production. In the first part of the experiments, a specific culture of Alcaligenes latus DSM 1124 was selected to ferment several types of food wastes as carbon sources into biopolymers. In addition, the biopolymer production, by way of using malt waste, of microorganisms from municipal activated sludge was also investigated. In the second part, the experiments focused on the synthesis of biopolymer with a higher molecular mass via the bacterial strain, which was selected and isolated from sesame oil, identified as Staphylococcus epidermidis . Molecular weight and molecular weight distribution of PHB were studied by GPC. Molecular weight of PHB produced from various types of food wastes by Alcaligenes latus was higher than using synthetic sucrose medium as nutrient, however, it resulted in the reverse by Staphylococcus epidermidis. Thermal properties of biopolymers were studied by DSC and TG. Using malt wastes as nutrients by Alcaligenes latus gave a higher melting temperature. Using sucrose, confectionery and sesame oil as nutrients by Staphylococcus epidermidis gave higher melting temperature. Optimization was carried out for the recovery of microbial PHB from Alcaligenes latus. Results showed that molecular weight can be controlled by changing the hypochlorite concentration, the ratio of chloroform to hypochlorite solution and the extraction time. In addition, the determination of PHB content by thermogravimetric analysis method with wet cell was the first report in our study. (Abstract shortened by UMI.)

The oral cavity is not a primary source for implantable pacemaker or cardioverter defibrillator infections

PubMed Central

2013-01-01

Background To test the hypothesis that the oral cavity is a potential source for implantable pacemaker and cardioverter defibrillators infections, the bacterial diversity on explanted rhythm heart management devices was investigated and compared to the oral microbiome. Methods A metagenomic approach was used to analyze the bacterial diversity on the surfaces of non-infected and infected pacemakers. The DNA from surfaces swaps of 24 non-infected and 23 infected pacemaker were isolated and subjected to bacterial-specific DNA amplification, single strand conformation polymorphism- (SSCP) and sequencing analysis. Species-specific primer sets were used to analyze for any correlation between bacterial diversity on pacemakers and in the oral cavity. Results DNA of bacterial origin was detected in 21 cases on infected pacemakers and assigned to the bacterial phylotypes Staphylococcus epidermidis, Propionibacterium acnes, Staphylococcus aureus, Staphylococcus schleiferi and Stapyhlococcus. In 17 cases bacterial DNA was found on pacemakers with no clinical signs of infections. On the basis of the obtained sequence data, the phylotypes Propionibacterium acnes, Staphylococcus and an uncultured bacterium were identified. Propionibacterium acnes and Staphylococcus epidermidis were the only bacteria detected in pacemeaker (n = 25) and oral samples (n = 11). Conclusions The frequency of the coincidental detection of bacteria on infected devices and in the oral cavity is low and the detected bacteria are highly abundant colonizers of non-oral human niches. The transmission of oral bacteria to the lead or device of implantable pacemaker or cardioverter defibrillators is unlikely relevant for the pathogenesis of pacemaker or cardioverter defibrillators infections. PMID:23575037

Use of a modified microplate bioassay method to investigate antibacterial activity in the Peruvian medicinal plant Peperomia galioides.

PubMed

Langfield, Richard D; Scarano, Frank J; Heitzman, Mary E; Kondo, Miwako; Hammond, Gerald B; Neto, Catherine C

2004-10-01

A versatile microplate bioassay for quick and sensitive determination of antibacterial activity was developed for use in screening medicinal plants and identification of their active principles. This assay can be used to determine minimum inhibitory concentrations for small quantities of organic or water-soluble plant extracts. Bioassay-guided fractionation of the stem and leaves of Peperomia galioides using this method found fractions containing grifolin and grifolic acid, which inhibited growth of Staphylococcus aureus and Staphylococcus epidermidis.

The use of newly developed real-time PCR for the rapid identification of bacteria in culture-negative osteomyelitis.

PubMed

Kobayashi, Naomi; Bauer, Thomas W; Sakai, Hiroshige; Togawa, Daisuke; Lieberman, Isador H; Fujishiro, Takaaki; Procop, Gary W

2006-12-01

We report a case of a culture-negative osteomyelitis in which our newly developed real-time polymerase chain reaction (PCR) could differentiate Staphylococcus aureus from Staphylococcus epidermidis. This is the first report that described the application of this novel assay to an orthopedics clinical sample. This assay may be useful for other clinical culture-negative cases in a combination with a broad-spectrum assay as a rapid microorganism identification method.

Detection of Staphylococcus Aureus Enterotoxin A and B Genes with PCR-EIA and a Hand-Held Electrochemical Sensor

DTIC Science & Technology

2004-06-11

Streptococcus pneumoniae 33400 Enterobacter cloaceae 49141 S. pyogenes 19615 E. aerogenes m10822 Vibrio cholerae N16961 Enterococcus durans 6056 Yersinia...identified. Thus the sensitivity for both assays was 100%. Of the 56 samples that lacked sea or seb genes, two false positives ( Enterobacter aerogenes ...Comanonas, Enterobacter , Enterococcus, Escherichia, Francisella, Haemophilus, Klebsiella, Listeria, Moraxella, Neisseria, Proteus, Pseudomonas, Salmonella

Diterpenoids from Salvia ceratophylla.

PubMed

Gören, Ahmet C; Topçu, Gülaçti; Oksüz, Sevil; Kökdil, Gamze; Voelter, Wolfgang; Ulubelen, Ayhan

2002-02-01

Salvia ceratophylla L. has yielded four known and two new diterpenoids together with two triterpenic acids, a steroid and a flavone. The structures of the compounds were established by spectroscopic analyses. One of the known compounds candidissiol exhibited a high antibacterial activity against Staphylococcus epidermidis and Proteus mirabilis.

Modulation of mecA Gene Expression by Essential Oil from Salvia sclarea and Synergism with Oxacillin in Methicillin Resistant Staphylococcus epidermidis Carrying Different Types of Staphylococcal Chromosomal Cassette mec

PubMed Central

Chovanová, Romana; Mikulášová, Mária; Vaverková, Štefánia

2016-01-01

The essential oil (EO) from Salvia sclarea was shown to increase the susceptibility of methicillin resistant Staphylococcus epidermidis (MRSE) isolates to oxacillin. The purpose of this study was to investigate the effect of EO from S. sclarea on expression of mecA gene of MRSE carrying different types of staphylococcal chromosomal cassette (SCCmec) and to evaluate potential synergistic effect of EO with oxacillin. Using real-time PCR we found that EO alone inhibited the expression of the resistant genes mecA, mecR1, and mecI and blaZ, blaR1, and blaI. The use of the combination of EO with oxacillin resulted in significantly inhibited expression of mecA gene in all tested strains with different types of SCCmec. Using time-kill assay and checkerboard assay we confirmed synergistic effect of EO from S. sclarea and oxacillin in MRSE. PMID:26880926

The biofilm-positive Staphylococcus epidermidis isolates in raw materials, foodstuffs and on contact surfaces in processing plants.

PubMed

Schlegelová, J; Babák, V; Holasová, M; Dendis, M

2008-01-01

Isolates from the "farm to fork" samples (182 isolates from 2779 samples) were examined genotypically (icaAB genes) and phenotypically (in vitro biofilm formation, typical growth on Congo red agar; CRA) with the aim to assess the risk of penetration of virulent strains of Staphylococcus epidermidis into the food chain. The contamination of meat and milk products was significantly higher in comparison with raw materials. Contamination of contact surfaces in the meat-processing plants was significantly lower than that of contact surfaces in the dairy plants. The ica genes (which precondition the biofilm formation) were concurrently detected in 20 isolates that also showed a typical growth on CRA. Two ica operon-negative isolates produced biofilm in vitro but perhaps by an ica-independent mechanism. The surfaces in the dairy plants and the milk products were more frequently contaminated with ica operon-positive strains (2.3 and 1.2 % samples) than the other sample types (0-0.6 % samples).

Primary processing of CRISPR RNA by the endonuclease Cas6 in Staphylococcus epidermidis.

PubMed

Wakefield, Noelle; Rajan, Rakhi; Sontheimer, Erik J

2015-10-07

In many bacteria and archaea, an adaptive immune system (CRISPR-Cas) provides immunity against foreign genetic elements. This system uses CRISPR RNAs (crRNAs) derived from the CRISPR array, along with CRISPR-associated (Cas) proteins, to target foreign nucleic acids. In most CRISPR systems, endonucleolytic processing of crRNA precursors (pre-crRNAs) is essential for the pathway. Here we study the Cas6 endonuclease responsible for crRNA processing in the Type III-A CRISPR-Cas system from Staphylococcus epidermidis RP62a, a model for Type III-A CRISPR-Cas systems, and define substrate requirements for SeCas6 activity. We find that SeCas6 is necessary and sufficient for full-length crRNA biogenesis in vitro, and that it relies on both sequence and stem-loop structure in the 3' half of the CRISPR repeat for recognition and processing. Copyright © 2015 Federation of European Biochemical Societies. Published by Elsevier B.V. All rights reserved.

The effect of octylglucoside and sodium cholate in Staphylococcus epidermidis and Pseudomonas aeruginosa adhesion to soft contact lenses.

PubMed

Santos, Lívia; Rodrigues, Diana; Lira, Madalena; Oliveira, Rosario; Real Oliveira, M Elisabete C D; Vilar, Eva Yebra-Pimentel; Azeredo, Joana

2007-05-01

In this study, the effect of the natural surfactants octylglucoside and sodium cholate in inhibiting Staphylococcus epidermidis and Pseudomonas aeruginosa adhesion to conventional and silicone-hydrogel contact lenses (CL) was assessed. Hydrophobicity was also evaluated to conditioned and nonconditioned CL. The inhibiting effect of the tested surfactants was determined through "in vitro" adhesion studies to conditioned and nonconditioned CL followed by image acquisition and cell enumeration. Hydrophobicity was evaluated through contact angle measurements using the advancing type technique on air. Sodium cholate exhibits a very low capability to inhibit microbial adhesion. Conversely, octylglucoside effectively inhibited microbial adhesion in both types of lenses. This surfactant exhibited an even greater performance than a multipurpose lens care solution used as control. Octylglucoside was the only tested surfactant able to lower the hydrophobicity of all CL, which can explain its high performance. The results obtained in this study point out the potential of octylglucoside as a conditioning agent to prevent microbial colonization.

Biological screening of some Turkish medicinal plant extracts for antimicrobial and toxicity activities.

PubMed

Turker, A U; Usta, C

2008-01-20

Screening of antibacterial activity and toxicity of 22 aqueous plant extracts from 17 Turkish plants was conducted. Antibacterial activity was performed with six bacteria including Escherichia coli, Pseudomonas aeruginosa, Klebsiella pneumoniae, Streptococcus pyogenes, Staphylococcus aureus and Staphylococcus epidermidis. Extracts of Tussilago farfara leaves, Helichyrsum plicatum flowers, Solanum dulcamara aerial parts and Urtica dioica leaves gave the best inhibitory activity against S. pyogenes, S. aureus and S. epidermidis. Of the 22 plant extracts, 20 extracts displayed toxicity (LC50 was <1000 mg L(-1)) in the brine shrimp bioassay. For radish seed bioassay, two different determinations (root length and seed germination) were performed with a comparison between two concentrations (50,000 mg L(-1) and 10,000 mg L(-1)). At low concentration (10,000 mg L(-1)), S. dulcamara aerial parts and Primula vulgaris leaf extracts were observed to inhibit the root length more than the other plant extracts. Also, the most inhibitive plant extract for seed germination was obtained with S. dulcamara aerial parts.

Staphylococcus epidermidis adhesion on surface-treated open-cell Ti6Al4V foams.

PubMed

Türkan, Uğur; Güden, Mustafa; Sudağıdan, Mert

2016-06-01

The effect of alkali and nitric acid surface treatments on the adhesion of Staphylococcus epidermidis to the surface of 60% porous open-cell Ti6Al4V foam was investigated. The resultant surface roughness of foam particles was determined from the ground flat surfaces of thin foam specimens. Alkali treatment formed a porous, rough Na2Ti5O11 surface layer on Ti6Al4V particles, while nitric acid treatment increased the number of undulations on foam flat and particle surfaces, leading to the development of finer surface topographical features. Both surface treatments increased the nanometric-scale surface roughness of particles and the number of bacteria adhering to the surface, while the adhesion was found to be significantly higher in alkali-treated foam sample. The significant increase in the number of bacterial attachment on the alkali-treated sample was attributed to the formation of a highly porous and nanorough Na2Ti5O11 surface layer.

Effects of BmCPV Infection on Silkworm Bombyx mori Intestinal Bacteria

PubMed Central

Zhang, Hao; Kumar, Dhiraj; Liu, Bo; Gong, Yongchang; Zhu, Min; Zhu, Liyuan; Liang, Zi; Kuang, Sulan; Chen, Fei; Hu, Xiaolong; Cao, Guangli; Xue, Renyu; Gong, Chengliang

2016-01-01

The gut microbiota has a crucial role in the growth, development and environmental adaptation in the host insect. The objective of our work was to investigate the microbiota of the healthy silkworm Bombyx mori gut and changes after the infection of B. mori cypovirus (BmCPV). Intestinal contents of the infected and healthy larvae of B. mori of fifth instar were collected at 24, 72 and 144 h post infection with BmCPV. The gut bacteria were analyzed by pyrosequencing of the 16S rRNA gene. 147(135) and 113(103) genera were found in the gut content of the healthy control female (male) larvae and BmCPV-infected female (male) larvae, respectively. In general, the microbial communities in the gut content of healthy larvae were dominated by Enterococcus, Delftia, Pelomonas, Ralstonia and Staphylococcus, however the abundance change of each genus was depended on the developmental stage and gender. Microbial diversity reached minimum at 144 h of fifth instar larvae. The abundance of Enterococcus in the females was substantially lower and the abundance of Delftia, Aurantimonas and Staphylococcus was substantially higher compared to the males. Bacterial diversity in the intestinal contents decreased after post infection with BmCPV, whereas the abundance of both Enterococcus and Staphylococcus which belongs to Gram-positive were increased. Therefore, our findings suggested that observed changes in relative abundance was related to the immune response of silkworm to BmCPV infection. Relevance analysis of plenty of the predominant genera showed the abundance of the Enterococcus genus was in negative correlation with the abundance of the most predominant genera. These results provided insight into the relationship between the gut microbiota and development of the BmCPV-infected silkworm. PMID:26745627

Effects of BmCPV Infection on Silkworm Bombyx mori Intestinal Bacteria.

PubMed

Sun, Zhenli; Lu, Yahong; Zhang, Hao; Kumar, Dhiraj; Liu, Bo; Gong, Yongchang; Zhu, Min; Zhu, Liyuan; Liang, Zi; Kuang, Sulan; Chen, Fei; Hu, Xiaolong; Cao, Guangli; Xue, Renyu; Gong, Chengliang

2016-01-01

The gut microbiota has a crucial role in the growth, development and environmental adaptation in the host insect. The objective of our work was to investigate the microbiota of the healthy silkworm Bombyx mori gut and changes after the infection of B. mori cypovirus (BmCPV). Intestinal contents of the infected and healthy larvae of B. mori of fifth instar were collected at 24, 72 and 144 h post infection with BmCPV. The gut bacteria were analyzed by pyrosequencing of the 16S rRNA gene. 147(135) and 113(103) genera were found in the gut content of the healthy control female (male) larvae and BmCPV-infected female (male) larvae, respectively. In general, the microbial communities in the gut content of healthy larvae were dominated by Enterococcus, Delftia, Pelomonas, Ralstonia and Staphylococcus, however the abundance change of each genus was depended on the developmental stage and gender. Microbial diversity reached minimum at 144 h of fifth instar larvae. The abundance of Enterococcus in the females was substantially lower and the abundance of Delftia, Aurantimonas and Staphylococcus was substantially higher compared to the males. Bacterial diversity in the intestinal contents decreased after post infection with BmCPV, whereas the abundance of both Enterococcus and Staphylococcus which belongs to Gram-positive were increased. Therefore, our findings suggested that observed changes in relative abundance was related to the immune response of silkworm to BmCPV infection. Relevance analysis of plenty of the predominant genera showed the abundance of the Enterococcus genus was in negative correlation with the abundance of the most predominant genera. These results provided insight into the relationship between the gut microbiota and development of the BmCPV-infected silkworm.

Influence of nanohydroxyapatite surface properties on Staphylococcus epidermidis biofilm formation.

PubMed

Barros, J; Grenho, L; Manuel, C M; Ferreira, C; Melo, L; Nunes, O C; Monteiro, F J; Ferraz, M P

2014-05-01

Nanohydroxyapatite (nanoHA), due to its chemical properties, has appeared as an exceptionally promising bioceramic to be used as bone regeneration material. Staphylococcus epidermidis have emerged as major nosocomial pathogens associated with infections of implanted medical devices. In this work, the purpose was to study the influence of the nanoHA surface characteristics on S. epidermidis RP62A biofilm formation. Therefore, two different initial inoculum concentrations (Ci) were used in order to check if these would affect the biofilm formed on the nanoHA surfaces. Biofilm formation was followed by the enumeration of cultivable cells and by scanning electron microscopy. Surface topography, contact angle, total surface area and porosimetry of the biomaterials were studied and correlated with the biofilm data. The surface of nanoHA sintered at 830 (nanoHA830) showed to be more resistant to S. epidermidis attachment and accumulation than that of nanoHA sintered at 1000 (nanoHA1000). The biofilm formed on nanoHA830 presented differences in terms of structure, surface coverage and EPS production when compared to the one formed on nanoHA1000 surface. It was observed that topography and surface area of nanoHA surfaces had influence on the bacterial attachment and accumulation. Ci influenced bacteria attachment and accumulation on nanoHA surfaces over time. The choice of the initial inoculum concentration was relevant proving to have an effect on the extent of adherence thus being a critical point for human health if these materials are used in implantable devices. This study showed that the initial inoculum concentration and surface material properties determine the rate of microbial attachment to substrata and consequently are related to biofilm-associated infections in biomaterials.

Antibacterial action of a heat-stable form of L-amino acid oxidase isolated from king cobra (Ophiophagus hannah) venom.

PubMed

Lee, Mui Li; Tan, Nget Hong; Fung, Shin Yee; Sekaran, Shamala Devi

2011-03-01

The major l-amino acid oxidase (LAAO, EC 1.4.3.2) of king cobra (Ophiophagus hannah) venom is known to be an unusual form of snake venom LAAO as it possesses unique structural features and unusual thermal stability. The antibacterial effects of king cobra venom LAAO were tested against several strains of clinical isolates including Staphylococcus aureus, Staphylococcus epidermidis, Pseudomonas aeruginosa, Klebsiella pneumoniae, and Escherichia coli using broth microdilution assay. For comparison, the antibacterial effects of several antibiotics (cefotaxime, kanamycin, tetracycline, vancomycin and penicillin) were also examined using the same conditions. King cobra venom LAAO was very effective in inhibiting the two Gram-positive bacteria (S. aureus and S. epidermidis) tested, with minimum inhibitory concentration (MIC) of 0.78μg/mL (0.006μM) and 1.56μg/mL (0.012μM) against S. aureus and S. epidermidis, respectively. The MICs are comparable to the MICs of the antibiotics tested, on a weight basis. However, the LAAO was only moderately effective against three Gram-negative bacteria tested (P. aeruginosa, K. pneumoniae and E. coli), with MIC ranges from 25 to 50μg/mL (0.2-0.4μM). Catalase at the concentration of 1mg/mL abolished the antibacterial effect of LAAO, indicating that the antibacterial effect of the enzyme involves generation of hydrogen peroxide. Binding studies indicated that king cobra venom LAAO binds strongly to the Gram-positive S. aureus and S. epidermidis, but less strongly to the Gram-negative E. coli and P. aeruginosa, indicating that specific binding to bacteria is important for the potent antibacterial activity of the enzyme. Copyright © 2010 Elsevier Inc. All rights reserved.

Staphylococcus epidermidis Isolated in 1965 Are More Susceptible to Triclosan than Current Isolates

PubMed Central

Skovgaard, Sissel; Nielsen, Lene Nørby; Larsen, Marianne Halberg; Skov, Robert Leo; Ingmer, Hanne; Westh, Henrik

2013-01-01

Since its introduction to the market in the 1970s, the synthetic biocide triclosan has had widespread use in household and medical products. Although decreased triclosan susceptibility has been observed for several bacterial species, when exposed under laboratory settings, no in vivo studies have associated triclosan use with decreased triclosan susceptibility or cross-resistance to antibiotics. One major challenge of such studies is the lack of strains that with certainty have not been exposed to triclosan. Here we have overcome this challenge by comparing current isolates of the human opportunistic pathogen Staphylococcus epidermidis with isolates collected in the 1960s prior to introduction of triclosan to the market. Of 64 current S. epidermidis isolates 12.5% were found to have tolerance towards triclosan defined as MIC≥0.25 mg/l compared to none of 34 isolates obtained in the 1960s. When passaged in the laboratory in the presence of triclosan, old and current susceptible isolates could be adapted to the same triclosan MIC level as found in current tolerant isolates. DNA sequence analysis revealed that laboratory-adapted strains carried mutations in fabI encoding the enoyl-acyl carrier protein reductase isoform, FabI, that is the target of triclosan, and the expression of fabI was also increased. However, the majority of the tolerant current isolates carried no mutations in fabI or the putative promoter region. Thus, this study indicates that the widespread use of triclosan has resulted in the occurrence of S. epidermidis with tolerance towards triclosan and that the adaptation involves FabI as well as other factors. We suggest increased caution in the general application of triclosan as triclosan has not shown efficacy in reducing infections and is toxic to aquatic organisms. PMID:23614034

Characterization of Ocular Methicillin-Resistant Staphylococcus epidermidis Isolates Belonging Predominantly to Clonal Complex 2 Subcluster II

PubMed Central

Hofling-Lima, Ana Luisa; Pignatari, Antonio C. C.

2014-01-01

Staphylococcus epidermidis is an abundant member of the microbiota of the human skin and wet mucosa, which is commonly associated with sight-threatening infections in eyes with predisposing factors. Ocular S. epidermidis has become notorious because of its capability to form biofilms on different ocular devices and due to the evolving rates of antimicrobial resistance. In this study, the molecular epidemiology of 30 ocular methicillin-resistant S. epidermidis (MRSE) isolates was assessed using multilocus sequence typing (MLST). Antimicrobial resistance, accessory gene-regulator and staphylococcal cassette chromosome mec (SCCmec) types, biofilm formation, and the occurrence of biofilm-associated genes were correlated with MLST clonal complexes. Sequence types (STs) frequently found in the hospital setting were rarely found in our collection. Overall, 12 different STs were detected with a predominance of ST59 (30%), ST5 and ST6 (13.3% each). Most of the isolates (93.3%) belonged to the clonal complex 2 (CC2) and grouped mainly within subcluster CC2-II (92.9%). Isolates grouped within this subcluster were frequently biofilm producers (92.3%) with a higher occurrence of the aap (84.5%) and bhp (46.1%) genes compared to icaA (19.2%). SCCmec type IV (53.8%) was predominant within CC2-II strains, while 38.4% were nontypeable. In addition, CC2-II strains were frequently multidrug resistant (80.7%) and demonstrated to be particularly resistant to ciprofloxacin (80.8%), ofloxacin (77%), azithromycin (61.5%), and gentamicin (57.7%). Our findings demonstrate the predominance of a particular MRSE cluster causing ocular infections, which was associated with high rates of antimicrobial resistance and particularly the carriage of biofilm-related genes coding for proteinaceous factors implicated in biofilm accumulation. PMID:24523473

Molecular Epidemiology of Staphylococcus epidermidis in a Neonatal Intensive Care Unit over a Three-Year Period

PubMed Central

Villari, P.; Sarnataro, C.; Iacuzio, L.

2000-01-01

Coagulase-negative staphylococci, especially Staphylococcus epidermidis, are increasingly important nosocomial pathogens, particularly in critically ill neonates. A 3-year prospective surveillance of nosocomial infections in a neonatal intensive care unit (NICU) was performed by traditional epidemiologic methods as well as molecular typing of microorganisms. The aims of the study were (i) to quantify the impact of S. epidermidis on NICU-acquired infections, (ii) to establish if these infections are caused by endemic clones or by incidentally occurring bacterial strains of this ubiquitous species, (iii) to evaluate the use of different methods for the epidemiologic typing of the isolates, and (iv) to characterize the occurrence and the spread of staphylococci with decreased glycopeptide susceptibility. Results confirmed that S. epidermidis is one of the leading causes of NICU-acquired infections and that the reduced glycopeptide susceptibility, if investigated by appropriate detection methods such as population analysis, is more common than is currently realized. Typing of isolates, which can be performed effectively through molecular techniques such as pulsed-field gel electrophoresis but not through antibiograms, showed that many of these infections are due to clonal dissemination and, thus, are potentially preventable by strict adherence to recommended infection control practices and the implementation of programs aimed toward the reduction of the unnecessary use of antibiotics. These strategies are also likely to have a significant impact on the frequency of the reduced susceptibility of staphylococci to glycopeptides, since this phenomenon appears to be determined either by more resistant clones transmitted from patient to patient or, to a lesser extent, by strains that become more resistant as a result of antibiotic pressure. PMID:10790091

New non-alcoholic formulation for hand disinfection.

PubMed

Biagi, Marco; Giachetti, Daniela; Miraldi, Elisabetta; Figura, Natale

2014-04-01

Hand washing is considered as the single most important strategy to prevent infections. World health organization (WHO) defines hand hygiene as a primary issue of personal care with particular reference to hospital personnel and health facility workers. In this work, we investigated a new combination for hand disinfection as an alternative to alcohol-based and chlorhexidine products. The new combination of 5-pyrrolidone-2-carboxylic acid (PCA) and copper sulphate pentahydrate (CS) was tested upon different bacterial species that normally colonize hands, including Staphylococcus aureus, methicillin resistant S. aureus (MR S. aureus), Staphylococcus epidermidis, multidrug resistant S. epidermidis (MDR S. epidermidis), Streptococcus pyogenes, Streptococcus agalactiae, Escherichia coli, Candida albicans and three clinical isolates: MR S. aureus, MDR S. epidermidis, and an E. coli strain. Minimal inhibitory concentrations (MICs), Minimal bactericidal concentrations (MBCs), fractional inhibitory concentration (FIC) indices, and fractional bactericidal concentration (FBC) indices were evaluated. Ethanol 70% V/V, isopropanol 60% V/V, and 4% w/V chlorhexidine solution were used as reference hand disinfectants. Copper sulphate pentahydrate was very effective against all tested microorganisms: The MIC and MBC for CS ranged from 781 mg/l against S. pyogenes to 12500 mg/l against E. coli strains and C. albicans. In addition, PCA exhibited a good antimicrobial activity, in particular, against S. pyogenes and S. agalactiae. The combination of CS and PCA showed a strong synergistic effect and all FIC indices were ≤0·500. The combination of CS and PCA were more effective than ethanol 70% V/V and isopropanol 60% V/V. In addition to antimicrobial activity, the new formulation possesses peculiar features such as residual activity and moisturizing effect. This work identifies a new strategy for hand disinfection.

Effect of dual delivery of antibiotics (vancomycin and cefazolin) and BMP-7 from chitosan microparticles on Staphylococcus epidermidis and pre-osteoblasts in vitro

PubMed Central

Mantripragada, Venkata P.; Jayasuriya, Ambalangodage C.

2016-01-01

The main aims of this manuscript are to: i) determine the effect of commonly used antibiotics to treat osteoarticular infections on osteoblast viability, ii) study the dual release of the growth factor (BMP-7) and antibiotics (vancomycin and cefazolin) from chitosan microparticles iii) demonstrate the bioactivity of the antibiotics released in vitro on Staphylococcus epidermidis. The novelty of this work is dual delivery of growth factor and antibiotic from the chitosan microparticles in a controlled manner without affecting their bioactivity. Cefazolin and vancomycin have different therapeutic concentrations for their action in vivo and therefore, two different concentrations of the drugs were used. Osteoblast cytotoxicity test concluded that cefazolin concentrations of 50 and 100 μg/ml were found to have positive influence on osteoblast proliferation. A significant increase in osteoblast proliferation was observed in the presence of cefazolin and BMP-7 in comparison with BMP-7 alone group; indicating cefazolin might play a role in osteoblast proliferation. On the other hand, vancomycin concentration of 1000 μg/ml was found to significantly reduce (p < 0.01) osteoblast proliferation in comparison with controls. The microbial study indicated that cefazolin at a minimum concentration of 21.5 μg/ml could inhibit ~85% growth of S. epidermidis, whereas vancomycin at a concentration of 30 μg/ml was found to inhibit ~80% bacterial growth. PMID:27287137

An in vitro investigation of bacteria-osteoblast competition on oxygen plasma-modified PEEK.

PubMed

Rochford, Edward T J; Subbiahdoss, Guruprakash; Moriarty, T Fintan; Poulsson, Alexandra H C; van der Mei, Henny C; Busscher, Henk J; Richards, R Geoff

2014-12-01

Polyetheretherketone (PEEK) films were oxygen plasma treated to increase surface free energy and characterized by X-ray photoelectron microscopy, atomic force microscopy, and water contact angles. A parallel plate flow chamber was used to measure Staphylococcus epidermidis, Staphylococcus aureus, and U-2 OS osteosarcomal cell-line adhesion to the PEEK films in separate monocultures. In addition, bacteria and U-2 OS cells were cocultured to model competition between osteoblasts and contaminating bacteria for the test surfaces. Plasma treatment of the surfaces increased surface oxygen content and decreased the hydrophobicity of the materials, but did not lead to a significant difference in bacterial or U-2 OS cell adhesion in the monocultures. In the S. epidermidis coculture experiments, the U-2 OS cells adhered in greater numbers on the treated surfaces compared to the untreated PEEK and spread to a similar extent. However, in the presence of S. aureus, cell death of the U-2 OS occurred within 10 h on all surfaces. The results of this study suggest that oxygen plasma treatment of PEEK may maintain the ability of osteoblast-like cells to adhere and spread, even in the presence of S. epidermidis contamination, without increasing the risk of preoperative bacterial adhesion. Therefore, oxygen plasma-treated PEEK remains a promising method to improve implant surface free energy for osseointegration. © 2014 Wiley Periodicals, Inc.

Antibacterial activity of fresh pomegranate juice against clinical strains of Staphylococcus epidermidis

PubMed Central

Betanzos-Cabrera, Gabriel; Montes-Rubio, Perla Y.; Fabela-Illescas, Héctor E.; Belefant-Miller, Helen; Cancino-Diaz, Juan C.

2015-01-01

Background Polyphenols have received a great deal of attention due to their biological functions. Pomegranate (Punica granatum L.) is a polyphenol-rich fruit. In the past decade, studies testing the antimicrobial activity of pomegranates almost exclusively used solvent extracts instead of fresh pomegranate juice (FPJ). The use of FPJ instead of solvent extracts would reduce toxicity issues while increasing patient acceptance. We established a model to test FPJ as a natural antimicrobial agent. Objective To evaluate the antimicrobial activity of FPJ on clinical isolates of multidrug-resistant Staphylococcus epidermidis strains. Design Sixty strains of S. epidermidis isolated from ocular infections were grown in the presence of FPJ, and minimum inhibitory concentration (MIC) was determined by broth and agar dilution methods. Results FPJ at 20% had a MIC equal to 100% (MIC100%) on all 60 strains tested. This inhibition of FPJ was confirmed by the growth kinetics of a multidrug-resistant strain exposed to different concentrations of FPJ. Additionally, the antimicrobial activity of FPJ was compared against commercial beverages containing pomegranate: Ocean Spray® had a MIC100% at 20%, followed by Del Valle® with a MIC15% at 20% concentration only. The beverages Jumex® and Sonrisa® did not have any antimicrobial activity. FPJ had the highest polyphenol content and antioxidant capacity. Conclusions Overall, FPJ had antimicrobial activity, which might be attributed to its high polyphenol content and antioxidant capacity. PMID:25999265

Biogenic gold nanoparticles enhance methylene blue-induced phototoxic effect on Staphylococcus epidermidis

NASA Astrophysics Data System (ADS)

Maliszewska, Irena; Leśniewska, Agata; Olesiak-Bańska, Joanna; Matczyszyn, Katarzyna; Samoć, Marek

2014-06-01

There is considerable current interest in photodynamic inactivation (PDI) as potential antimicrobial therapy. This study reports successful implementation of PDI of Staphylococcus epidermidis using methylene blue (MB) in combination with biogenic gold nanoparticles (GNP). Monodispersed colloidal GNP were synthesized by reduction of Au+3 in the presence of cell-free filtrate of Trichoderma koningii and were characterized by a number of techniques including UV-Vis and fluorescence spectroscopy, transmission electron microscopy (TEM), and Fourier transform infrared spectroscopy (FTIR) to be 12 ± 3 nm spherical gold particles coated with proteins. Studies on the role of the cell-free filtrate proteins in the synthesis of the GNP indicate that the process is nonenzymatic but involves interactions of various amino acids with gold ions. A Xe lamp (550-780 nm) or a He-Ne laser (632 nm) was used as light sources to study the effect of MB alone, the GNP alone, and the MB-GNP mixture on the viability of bacterial cells. Lethal photosensitization of S. epidermidis with the MB-GNP mixture was achieved after 5 and 10 min exposure to laser or Xe lamp, respectively. It has been found that the MB-GNP mixture exhibits a significant antibacterial activity already in the absence of any light source and gives an enhanced antimicrobial response when using either a laser or a Xe lamp source for photosensitization.

Endocarditis caused by Rhodotorula infection.

PubMed

Simon, Matthew S; Somersan, Selin; Singh, Harjot K; Hartman, Barry; Wickes, Brian L; Jenkins, Stephen G; Walsh, Thomas J; Schuetz, Audrey N

2014-01-01

Rhodotorula is an emerging opportunistic fungal pathogen that is rarely reported to cause endocarditis. We describe a case involving a patient who developed endocarditis due to Rhodotorula mucilaginosa and Staphylococcus epidermidis, proven by culture and histopathology. The case illustrates the unique diagnostic and therapeutic challenges relevant to Rhodotorula spp.

The narrowing down of inoculated communities of coagulase-negative staphylococci in fermented meat models is modulated by temperature and pH.

PubMed

Stavropoulou, Despoina Angeliki; Van Reckem, Emiel; De Smet, Stefaan; De Vuyst, Luc; Leroy, Frédéric

2018-06-02

Coagulase-negative staphylococci (CNS) are involved in colour and flavour formation of fermented meats. Their communities are established either spontaneously, as in some artisan-type products, or using a starter culture. The latter usually consists of Staphylococcus carnosus and/or Staphylococcus xylosus strains, although strains from other CNS species also have potential for application. However, it is not entirely clear how the fitness of alternative starter cultures within a fermented meat matrix compares to conventional ones and how this may be affected by processing conditions. Therefore, the aim of this study was to assess the influence of two key processing conditions, namely temperature and acidity, on the competitiveness of a cocktail of five different strains of CNS belonging to species that are potentially important for meat fermentation (Staphylococcus xylosus 2S7-2, S. carnosus 833, Staphylococcus epidermidis ATCC 12228, Staphylococcus equorum DFL-S19, and Staphylococcus saprophyticus FPS1). To this end, fermented meat models consisting of cured meat batters with initial pH values of 5.3, 5.5, or 5.7 were inoculated with these strains, stuffed in containers, and incubated at 23, 30, or 37 °C. Both the pH level and the temperature influenced the composition of the CNS communities, giving a competitive advantage to the best adapted species. Staphylococcus xylosus preferred low temperature and mild acidity, whereas an elevated temperature selected for S. epidermidis and a low pH for S. carnosus. Under the conditions tested, S. saprophyticus and S. equorum were outcompeted by the three other CNS species. Hence, CNS communities in fermented meats are not only established based on the initial presence of specific species in the meat batter but also by their subsequent adaptation to the processing conditions during fermentation, potentially overruling the use of starter cultures. Copyright © 2018 Elsevier B.V. All rights reserved.

Modeling antibiotic and cytotoxic effects of the dimeric isoquinoline IQ-143 on metabolism and its regulation in Staphylococcus aureus, Staphylococcus epidermidis and human cells

PubMed Central

2011-01-01

Background Xenobiotics represent an environmental stress and as such are a source for antibiotics, including the isoquinoline (IQ) compound IQ-143. Here, we demonstrate the utility of complementary analysis of both host and pathogen datasets in assessing bacterial adaptation to IQ-143, a synthetic analog of the novel type N,C-coupled naphthyl-isoquinoline alkaloid ancisheynine. Results Metabolite measurements, gene expression data and functional assays were combined with metabolic modeling to assess the effects of IQ-143 on Staphylococcus aureus, Staphylococcus epidermidis and human cell lines, as a potential paradigm for novel antibiotics. Genome annotation and PCR validation identified novel enzymes in the primary metabolism of staphylococci. Gene expression response analysis and metabolic modeling demonstrated the adaptation of enzymes to IQ-143, including those not affected by significant gene expression changes. At lower concentrations, IQ-143 was bacteriostatic, and at higher concentrations bactericidal, while the analysis suggested that the mode of action was a direct interference in nucleotide and energy metabolism. Experiments in human cell lines supported the conclusions from pathway modeling and found that IQ-143 had low cytotoxicity. Conclusions The data suggest that IQ-143 is a promising lead compound for antibiotic therapy against staphylococci. The combination of gene expression and metabolite analyses with in silico modeling of metabolite pathways allowed us to study metabolic adaptations in detail and can be used for the evaluation of metabolic effects of other xenobiotics. PMID:21418624

Application of air ions for bacterial de-colonization in air filters contaminated by aerosolized bacteria.

PubMed

Kim, Yang Seon; Yoon, Ki Young; Park, Jae Hong; Hwang, Jungho

2011-01-15

We aerosolized the Escherichia coli (E. coli) and Staphylococcus epidermidis (S. epidermidis) bacteria and collected them on membrane filters. Then we generated air ions by applying a high voltage to a carbon fiber tip and applied them to the contaminated filters. The antibacterial efficiency was not significantly affected by the bacteria being Gram-positive or Gram-negative, however, negative ions showed a lower antibacterial efficiency than positive ions to both E. coli and S. epidermidis, even though the concentration of negative air ions was much higher than that of positive air ions. With a field emission scanning electron microscope (FE-SEM) images and fluorescence microscopy images using a LIVE/DEAD BacLight Bacterial Viability Kit, electrostatic disruption of the bacteria was found to be the dominant antibacterial effect. Copyright © 2010 Elsevier B.V. All rights reserved.

Genetic and phenotypic characterization of methicillin-resistant staphylococci isolated from veterinary hospitals in South Korea.

PubMed

Moon, Bo Youn; Youn, Jung-Ho; Shin, Sook; Hwang, Sun Young; Park, Yong Ho

2012-05-01

Staphylococci were isolated from veterinary staff, hospitalized animals, and medical equipment from 2 major tertiary veterinary hospitals in South Korea to investigate antimicrobial resistance and genetic relatedness. The detection rate for staphylococci was 55.2% (111/201 samples), and 11 species were identified among the collected staphylococcal strains. The most prevalent species were Staphylococcus pseudintermedius (52/111, 46.8%), Staphylococcus epidermidis (21/111, 18.9%), and Staphylococcus aureus (19/111, 17.1%). The methicillin-resistance rates of staphylococci isolated from veterinary staff and medical equipment were higher than those from hospitalized animals. The genotype of methicillin-resistant S. aureus (MRSA) strains in the current study was sequence type (ST)72-SCCmec IVc-t324, which is similar to the genotype of prevalent MRSA strains in human beings and food animals in South Korea. Among the mecA-positive S. pseudintermedius isolates, SCCmec V was most prevalent in strains originating from both veterinary staff and hospitalized animals. SCCmec IVa was detected in methicillin-resistant S. epidermidis, whereas SCCmec IVc was found in other methicillin-resistant, coagulase-negative staphylococci. The SCCmec typing, antimicrobial susceptibility tests, and pulsed field gel electrophoresis results showed that methicillin-resistant staphylococci dissemination between hospitalized animals and veterinary staff is possible in South Korean veterinary hospitals.

Identification of Emerging Human Mastitis Pathogens by MALDI-TOF and Assessment of Their Antibiotic Resistance Patterns

PubMed Central

Marín, María; Arroyo, Rebeca; Espinosa-Martos, Irene; Fernández, Leónides; Rodríguez, Juan M.

2017-01-01

Lactational mastitis constitutes one of the main causes of undesired weaning, depriving the mother–infant pair from the benefits of breastfeeding; therefore, this condition should be considered a relevant public health issue. The role of specific microorganisms remains unclear since human milk cultures and antibiotic susceptibility testing (AST) are not routinely performed, despite the fact that this would be key to ensure an early and effective diagnosis and treatment. The objective of this study was to describe the culturable microbial diversity in 647 milk samples from breastfeeding women with clinical symptoms of mastitis by Matrix-Assisted Laser Desorption Ionization Time-of-Flight Mass Spectrometry (MALDI-TOF) VITEK MS technology and to analyze the antimicrobial susceptibility profiles of a collection of isolates from these samples by the VITEK 2 AST system. Staphylococcus epidermidis was the most common species isolated from mastitis samples (87.6%), while Staphylococcus aureus was detected in 22.1%. Streptococci constituted the second (68.6%) most prevalent bacterial group, with Streptococcus mitis/oralis, Streptococcus salivarius, and Streptococcus parasanguinis detected with frequencies of 40.8, 36.8, and 14.4%, respectively. The antibiotic susceptibility profiles of 642 staphylococcal isolates indicated a remarkable resistance to benzylpenicillin (88.3%) and erythromycin (67.3%) with differences between species. A high percentage of Staphylococcus isolates were resistant to at least one antibiotic (Staphylococcus hominis, 100%; S. epidermidis, 98.2%; S. aureus, 92.9%; Staphylococcus lugdunensis, 90.5%) and the percentage of multidrug-resistance (MDR) isolates was noticeable (S. hominis, 81%; S. epidermidis, 64.4%; S. aureus, 11.5%; S. lugdunensis, 10.5%). In relation to streptococcal isolates (n = 524), AST revealed high or moderate percentages of resistance to erythromycin (68.7%), benzylpenicillin (63.7%), ampicillin (51.5%), and tetracycline (30.8%). Antibiotic resistance to at least one antibiotic was detected in 97.6% of S. parasanguinis, 92.6% of S. salivarius, 83.3% of S. mitis/oralis, and 72.4% of Streptococcus vestibularis isolates. A significant number of MDR streptococcal isolates was also found (S. parasanguinis, 51.2%; S. salivarius, 39.3%; S. mitis/oralis, 34.6%; and S. vestibularis, 19%). The results highlight the important role of coagulase-negative staphylococci and streptococci as human mastitis-causing agents. Moreover, the high rates of antimicrobial resistance among these microorganisms must be contemplated as an issue of clinical relevance in relation to treatment options. PMID:28747897

Comparison of antibiotic resistance, biofilm formation and conjugative transfer of Staphylococcus and Enterococcus isolates from International Space Station and Antarctic Research Station Concordia.

PubMed

Schiwon, Katarzyna; Arends, Karsten; Rogowski, Katja Marie; Fürch, Svea; Prescha, Katrin; Sakinc, Türkan; Van Houdt, Rob; Werner, Guido; Grohmann, Elisabeth

2013-04-01

The International Space Station (ISS) and the Antarctic Research Station Concordia are confined and isolated habitats in extreme and hostile environments. The human and habitat microflora can alter due to the special environmental conditions resulting in microbial contamination and health risk for the crew. In this study, 29 isolates from the ISS and 55 from the Antarctic Research Station Concordia belonging to the genera Staphylococcus and Enterococcus were investigated. Resistance to one or more antibiotics was detected in 75.8 % of the ISS and in 43.6 % of the Concordia strains. The corresponding resistance genes were identified by polymerase chain reaction in 86 % of the resistant ISS strains and in 18.2 % of the resistant Concordia strains. Plasmids are present in 86.2 % of the ISS and in 78.2 % of the Concordia strains. Eight Enterococcus faecalis strains (ISS) harbor plasmids of about 130 kb. Relaxase and/or transfer genes encoded on plasmids from gram-positive bacteria like pIP501, pRE25, pSK41, pGO1 and pT181 were detected in 86.2 % of the ISS and in 52.7 % of the Concordia strains. Most pSK41-homologous transfer genes were detected in ISS isolates belonging to coagulase-negative staphylococci. We demonstrated through mating experiments that Staphylococcus haemolyticus F2 (ISS) and the Concordia strain Staphylococcus hominis subsp. hominis G2 can transfer resistance genes to E. faecalis and Staphylococcus aureus, respectively. Biofilm formation was observed in 83 % of the ISS and in 92.7 % of the Concordia strains. In conclusion, the ISS isolates were shown to encode more resistance genes and possess a higher gene transfer capacity due to the presence of three vir signature genes, virB1, virB4 and virD4 than the Concordia isolates.

Microbial diversity and dynamics during the production of May bryndza cheese.

PubMed

Pangallo, Domenico; Saková, Nikoleta; Koreňová, Janka; Puškárová, Andrea; Kraková, Lucia; Valík, Lubomír; Kuchta, Tomáš

2014-01-17

Diversity and dynamics of microbial cultures were studied during the production of May bryndza cheese, a traditional Slovak cheese produced from unpasteurized ewes' milk. Quantitative culture-based data were obtained for lactobacilli, lactococci, total mesophilic aerobic counts, coliforms, E. coli, staphylococci, coagulase-positive staphylococci, yeasts, fungi and Geotrichum spp. in ewes' milk, curd produced from it and ripened for 0 - 10 days, and in bryndza cheese produced from the curd, in three consecutive batches. Diversity of prokaryotes and eukaryotes in selected stages of the production was studied by non-culture approach based on amplification of 16S rDNA and internal transcribed spacer region, coupled to denaturing gradient gel electrophoresis and sequencing. The culture-based data demonstrated an overall trend of growth of the microbial population contributing to lactic acid production and to ripening of the cheese, lactobacilli, lactococci and Geotrichum spp. growing up to densities of 10(8) CFU/g, 10(9) CFU/g and 10(5) CFU/g, respectively, in all three consecutive batches of bryndza cheese. The diversity of bacteria encompassed Acinetobacter calcoaceticus, Acinetobacter guillouiae, Acinetobacter sp., Acinetobacter johnsonii, Citrobacter braakii, Clostridium bartlettii, Corynebacterium callunae, Corynebacterium maris, Enterobacter aerogenes, Enterobacter asburiae, Enterobacter hormaechei, Enterococcus faecium, Enterococcus pallens, Escherichia coli, Haemophilus haemolyticus, Hafnia alvei, Kluyvera cryocrescens, Lactobacillus helveticus, Lactococcus garvieae, Lc. lactis subsp. cremoris, Lc. lactis subsp. lactis, "Leuconostoc garlicum", Mannheimia glucosida, Mannheimia haemolytica, Pseudomonas sp., Ps. fluorescens, "Ps. reactans", Raoultella ornithinolytica, R. terrigena, "Rothia arfidiae", Staphylococcus aureus, Staph. epidermidis, Staph. felis, Staph. pasteuri, Staph. sciuri, Staph. xylosus, Streptococcus parauberis, Str. thermophilus and Variovorax paradoxus. The diversity of yeasts and fungi encompassed Alternaria alternata, "Ascomycete sp.", Aspergillus fumigatus, Beauveria brongniartii, Candida xylopsoci, C. inconspicua, Cladosporium cladosporioides, Debaromyces hansenii, Fomes fomentarius, Galactomyces candidus, Gymnoascus reesii, Chaetomium globosum, Kluyveromyces marxianus, Metarhizium anisopliae, Penicillium aurantiogriseum, P. camemberti, P. freii, P. polonicum, P. viridicatum, Pichia kudriavzevii, Sordaria alcina, Trichosporon lactis and Yarrowia lipolytica. © 2013.

Endocarditis Caused by Rhodotorula Infection

PubMed Central

Simon, Matthew S.; Somersan, Selin; Singh, Harjot K.; Hartman, Barry; Wickes, Brian L.; Jenkins, Stephen G.; Walsh, Thomas J.

2014-01-01

Rhodotorula is an emerging opportunistic fungal pathogen that is rarely reported to cause endocarditis. We describe a case involving a patient who developed endocarditis due to Rhodotorula mucilaginosa and Staphylococcus epidermidis, proven by culture and histopathology. The case illustrates the unique diagnostic and therapeutic challenges relevant to Rhodotorula spp. PMID:24197888

IN VITRO ANTIMICROBIAL SCREENING OF AQUILARIA AGALLOCHA ROOTS.

PubMed

Canlı, Kerem; Yetgin, Ali; Akata, Ilgaz; Altuner, Ergin Murat

2016-01-01

It was previously shown that some parts of Aquilaria agallocha , which is commonly known as oud or oodh, such as roots have been used as a traditional medical herbal in different countries. In Turkey A. agallocha is one of the ingredients while preparing famous Mesir paste, which was invented as a medicinal paste and used from the Ottoman period to now at least for 500 years. The identification the in vitro antimicrobial activity of ethanol extract of A. agallocha roots is main purpose of this analysis. By using 17 bacteria and 1 fungi, which include Bacillus, Candida, Enterobacter, Enterococcus, Escherichia, Klebsiella, Listeria, Pseudomonas, Salmonella and Staphylococcus genera, the activity of A. agallocha root extracts were analysed by the help of the disk diffusion method, that is one of the methods commonly used to determine antimicrobial activities. As a result of the study it was observed that ethanol extracts of A. agallocha roots have a clear antimicrobial activity against nearly all microorganism used in the study, but only two bacteria namely E. coli ATCC 25922 and S. typhimurium SL 1344. According to the disk diffusion test results it may be possible to propose that A. agallocha roots should have a medicinal uses especially against E. faecium , L. monocytogenes ATCC 7644, B. subtilis DSMZ 1971, C. albicans DSMZ 1386, S. epidermidis DSMZ 20044 and S. aureus ATCC 25923.

Strain-specific inhibition of the adherence of uropathogenic bacteria to bladder cells by probiotic Lactobacillus spp.

PubMed

de Llano, Dolores González; Arroyo, Amalia; Cárdenas, Nivia; Rodríguez, Juan Miguel; Moreno-Arribas, M Victoria; Bartolomé, Begoña

2017-06-01

Urinary tract infections (UTIs), one of most common infections worldwide, face high recurrence rates and increasing antimicrobial resistance. Probiotic bacteria, especially of the genus Lactobacillus, are considered a promising preventive and/or treatment therapy against UTIs. In order to elucidate the mechanisms involved in these beneficial effects, we studied the impact of different Lactobacillus strains (Lactobacillus salivarius UCM572, L. plantarum CLC17 and L. acidophilus 01) in the adherence of reference and clinical uropathogenic strains (Escherichia coli ATCC® 53503, E. coli 10791, Enterococcus faecalis 04-1, En. faecalis 08-1 and Staphylococcus epidermidis 08-3) to T24 epithelial bladder cells. In general, the Lactobacillus strains with previous in vivo evidence of beneficial effects against UTIs (L. salivarius UCM572 and L. acidophilus 01) significantly inhibited the adherence of the five uropathogens to T24 cells, displaying percentages of inhibition ranging between 22.2% and 43.9%, and between 16.5% and 53.7%, respectively. On the other hand, L. plantarum CLC17, a strain with no expected effects on UTIs, showed almost negligible anti-adherence effects.Therefore, these in vitro results suggest that inhibition of the adherence of uropathogens to epithelial bladder cells may be one of the mechanisms involved in the potential beneficial effects of probiotics against UTIs in vivo. © FEMS 2017. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Chemical composition and antimicrobial activity of the essential oils of Pinus peuce (Pinaceae) growing wild in R. Macedonia.

PubMed

Karapandzova, Marija; Stefkova, Gjose; Cvetkovikj, Ivana; Trajkovska-Dokik, Elena; Kaftandzieva, Ana; Kulevanova, Svetlana

2014-11-01

The chemical composition and antimicrobial activity of the essential oils isolated from twigs with needles (T+N) and from twigs without needles (T-N) from wild Pinus peuce Griseb. (Pinaceae), from three different locations in R. Macedonia, were investigated. Essential oil yields of T+N ranged from 7.5 mL/kg to 12.5 mL/kg and for T-N from 13.8 mL/kg to 17.3 mL/kg. GC/FID/MS analysis of the essential oils revealed eighty-four components, representing 93.7-95.7% and 91.2-92.0% of the T+N and T-N oils, respectively. The major components in T+N and T-N oils were monoterpenes: α-pinene (23.8-39.9%, 21.2-23.3%), camphene (2.2-5.5%, 0.7-2.0%), β-pinene (10.1-17.1%, 8.2-16.4%), myrcene (1.2-1.41%, 1.6-2.5%), limonene+β-phellandrene (6.8-14.0%, 8.8-23.6%) and bornyl acetate (2.3-6.9%, 1.1-3.4%), followed by the sesquiterpenes: trans-(E)-caryophyllene (3.6-4.3%, 3.2-7.3%), germacrene D (7.1-9.5%, 5.0-10.3%) and δ-cadinene (2.1-3.1%, 3.3-4.2%, respectively). Antimicrobial screening of the essential oils was made by disk diffusion and broth dilution methods against 13 bacterial isolates of Gram-positive and Gram-negative bacteria and one strain of Candida albicans. T-N essential oils showed antimicrobial activity toward Streptococcus pneumoniae, Staphylococcus aureus, S. epidermidis and Candida albicans as well as Streptococcus agalactiae, Acinetobacter spp. and Haemophilus influenzae. The antimicrobial activity of T+N essential oils was greater, especially against Streptococcus agalactiae, S. pyogenes, Enterococcus and Candida albicans, followed by Haemophilus influenzae, Acinetobacter spp., Escherichia coli, Salmonella enteritidis, Staphylococcus aureus and S. epidermidis. Minimal inhibitory concentrations (MICs) of all tested essential oils ranged from 15-125 μL/mL. Summarizing the obtained results, the antimicrobial activity of Pinus peuce T+N and T-N essential oils collected from different localities in R. Macedonia varied considerably. These alterations in the antimicrobial activity can be attributed to the differences in the quantitative composition and percentage amounts of the components present in the respective essential oils, although it was evident that there were no differences in the qualitative composition of the essential oils, regardless of the locality of collection, or the type of plant material (T+N or T-N).

[Investigation of antimicrobial and antibiofilm effects of some preservatives used in drugs, cosmetics and food products].

PubMed

Güven, Nihal; Kaynak Onurdağ, Fatma

2014-01-01

Preservatives are added to food, drugs and other pharmaceutical products to avoid microbial contamination. For antimicrobial activity testing and preservative efficacy testing, vegetative forms of the standard test organisms are used. However, microbial biofilm formation may occur on living tissues, medical implants, industrial or drinking water pipes, natural aquatic systems, glass and plastic surfaces. In our study, it was aimed to determine the antimicrobial and antibiofilm effects of some preservatives used in drug, cosmetics and food products and to compare the minimum biofilm inhibitory concentration (MBIC) of microbial biofilm formed on glass surfaces which are commonly used in those areas and the minimum inhibitory concentration (MIC) values of the planktonic forms. In the study Pseudomonas aeruginosa ATCC 27853, Salmonella Thyphimurium SL1344, Staphylococcus aureus ATCC 6538, Staphylococcus epidermidis NCTC 11047, Enterococcus faecalis ATCC 29212 and Candida albicans ATCC 10231 were used as the standard strains; sodium nitrate, methylparaben, prophylparaben, potassium sorbate and sodium benzoate as the preservatives; ampicillin, vancomycin, gentamicin, ciprofloxacin, amphotericin B and itraconazole as the antimicrobial agents. MIC values were determined through the guidelines of CLSI M100-S18 and M27-A3 protocols. BioTimer method was used to determine the MBIC values. The value of "colony forming unit (CFU)/glass beads" was calculated using the graphics drawn by plotting the time of color change for phenol red or resazurin against log10CFU. All experiments were done with four media at different pH values namely pH: 7, pH: 6.5, pH: 6 and pH: 5.5. According to the results of tests on planktonic forms of the microorganisms, sodium benzoate was determined to be the most effective preservative against all the microorganisms tested except S.aureus and E.faecalis. The most effective preservative against S.aureus and E.faecalis was prophylparaben. Prophylparaben was also effective against S.epidermidis. However, in our study it was determined that preservatives were not effective against biofilm forms even if the inoculum was lower, equal to or higher than the inocula of the planktonic forms. The data obtained from this study indicated that preservatives used to prevent microbial contamination in pharmaceutical, cosmetic and food products, are not effective against biofilm forms of the microorganisms. This study is thought to be a guide for further studies to be held in the investigation of antimicrobial and antibiofilm effects of preservatives used in drugs, cosmetics and food industry.

Persistence of mixed staphylococci assemblages following disinfection of hospital room surfaces.

PubMed

Sigler, V; Hensley, S

2013-03-01

The distribution of staphylococcal assemblages on surfaces in hospital rooms was assessed before and after daily disinfection with quaternary ammonia products. DNA was extracted from enrichment cultures of bacteria, which were swabbed from each of nine surface types, and subjected to analysis by staphylococci-specific, denaturing gradient gel electrophoresis. A genetic marker for Staphylococcus epidermidis/kloosii was detected on all surface types before and after cleaning, whereas markers for Staphylococcus aureus and Staphylococcus lugdunensis were detected on five surface types. Overall, genetic makers for several staphylococci known to colonize and infect humans remained ubiquitous in each room following daily disinfection practices. Copyright © 2013 The Healthcare Infection Society. Published by Elsevier Ltd. All rights reserved.

Microorganisms present on peripheral intravenous needleless connectors in the clinical environment.

PubMed

Slater, Karen; Cooke, Marie; Whitby, Michael; Fullerton, Fiona; Douglas, Joel; Hay, Jennine; Rickard, Claire

2017-08-01

The aim of this study was to quantify culturable microorganisms on needleless connectors (NCs) attached to peripheral intravenous catheters in hospitalized adult medical patients. Half (50%) of 40 NCs were contaminated with microorganisms commonly found on the skin or mouth. Staphylococcus capitis and Staphylococcus epidermidis were most commonly isolated. Emergency department insertion and higher patient dependency were statistically associated with positive NC microorganism growth. These results reaffirm the need for NC decontamination prior to access. Crown Copyright © 2017. Published by Elsevier Inc. All rights reserved.

Mutations in Ribosomal Protein L3 Are Associated with Oxazolidinone Resistance in Staphylococci of Clinical Origin▿

PubMed Central

Locke, Jeffrey B.; Hilgers, Mark; Shaw, Karen Joy

2009-01-01

Following recent reports of ribosomal protein L3 mutations in laboratory-derived linezolid-resistant (LZDr) Staphylococcus aureus, we investigated whether similar mutations were present in LZDr staphylococci of clinical origin. Sequence analysis of a variety of LZDr isolates revealed two L3 mutations, ΔSer145 (S. aureus NRS127) and Ala157Arg (Staphylococcus epidermidis 1653059), both occurring proximal to the oxazolidinone binding site in the peptidyl transferase center. The oxazolidinone torezolid maintained a ≥8-fold potency advantage over linezolid for both strains. PMID:19805557

Two new monoterpenoid glycosides from the fresh rhizome of Tongling White Ginger (Zingiber officinale).

PubMed

Guo, Tao; Tan, Su-Bei; Wang, Ya; Chang, Jun

2018-01-01

Two new monoterpenoid glycosides, trans-1,8-cineole-3,6-dihydroxy-3-O-β-D-glucopyranoside (1), and 5,9-dihydroxy borneol 2-O-β-D-glucopyranoside (2), together with four known monoterpenoid glycosides (3-6), were isolated from the water-soluble constituents of the fresh rhizome of Tongling White Ginger (Zingiber officinale). Their structures were decisively elucidated by spectroscopic analysis. In vitro tests for antimicrobial activity showed that compounds 1 and 3 possess significant activity against two Gram-positive organisms, Staphylococcus aureus and Staphylococcus epidermidis.

[Prostate histopathology of NIH category IV prostatitis detected by sextant prostate needle biopsy from the patients with high prostatic specific antigen].

PubMed

Shimomura, Tatsuya; Kiyota, Hiroshi; Takahashi, Hiroyuki; Madarame, Jun; Kimura, Takahiro; Onodera, Shouichi

2003-08-01

Asymptomatic prostatitis is classified as category IV in NIH classification of prostatitis syndrome (1999). No report concerning this category has been present. We investigated this category histopathologically and clinically, in order to clarify the histopathological distribution and its correlation to the clinical features, in this study. Among 785 patients who were suspected prostate cancer because of their high prostatic specific antigen (PSA) values and to have a sextant prostate needle biopsy was performed between January, 1996 and December, 2000, 88 patients (11.2%) were diagnosed as NIH category IV prostatitis (asymptomatic prostatitis). We observed all pathological specimens stained with Hematoxylin-Eosine, and classified them into subtypes according to the classification criteria for prostatitis defined by True et al. (1999). We also investigated the relationship between histopathological distribution and clinical features such as PSA values, PSA density, the incidence of pyuria or bacteriuria. In the histopathological study, grade distributions were 12.5% (11/88) in mild, 71.6% (63/88) in moderate, and 15.9% (14/88) in severe. Location distributions were 2.3% (2/88) in glandular, 68.2% (60/88) in periglandular, and 29.5% (26/88) in stromal. No relationship between these subtypes and clinical features was recognized statistically. However, 7 patients (7.95%) were diagnosed as prostate cancers, later. Pyuria was found in 29.1% (23/79). Bacteriuria was present in 14.3% (11/77). Isolated bacteria were 4 strains of Enterococcus faccalis, 2 strains of each of Pseudomonas aeruginosa and Staphylococcus aureus, and one strain of each of Escherichia coli, Klebsiella oxytoca, Enterobacter cloacae, Enterobacter aerogenes, Staphylococcus haemolyticus, and Staphylococcus epidermidis. Gram positive rod, and Candida sp. No relationship between these subtypes and bacterial species was recognized. These results indicated that the incidence of NIII category IV prostatits was not low without correlation to any clinical features. However, we should pay attention to the presence of prostate cancer, because a small number of the patients were diagnosed as prostate cancer, later.

DNA Microarray for Detection of Macrolide Resistance Genes

PubMed Central

Cassone, Marco; D'Andrea, Marco M.; Iannelli, Francesco; Oggioni, Marco R.; Rossolini, Gian Maria; Pozzi, Gianni

2006-01-01

A DNA microarray was developed to detect bacterial genes conferring resistance to macrolides and related antibiotics. A database containing 65 nonredundant genes selected from publicly available DNA sequences was constructed and used to design 100 oligonucleotide probes that could specifically detect and discriminate all 65 genes. Probes were spotted on a glass slide, and the array was reacted with DNA templates extracted from 20 reference strains of eight different bacterial species (Streptococcus pneumoniae, Streptococcus pyogenes, Enterococcus faecalis, Enterococcus faecium, Staphylococcus aureus, Staphylococcus haemolyticus, Escherichia coli, and Bacteroides fragilis) known to harbor 29 different macrolide resistance genes. Hybridization results showed that probes reacted with, and only with, the expected DNA templates and allowed discovery of three unexpected genes, including msr(SA) in B. fragilis, an efflux gene that has not yet been described for gram-negative bacteria. PMID:16723563

Genetic characterization of antimicrobial resistance in coagulase-negative staphylococci from bovine mastitis milk.

PubMed

Frey, Yvonne; Rodriguez, Joan Peña; Thomann, Andreas; Schwendener, Sybille; Perreten, Vincent

2013-04-01

Coagulase-negative staphylococci (CNS; n=417) were isolated from bovine milk and identified by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. Nineteen different species were identified, and Staphylococcus xylosus, Staphylococcus chromogenes, Staphylococcus haemolyticus, and Staphylococcus sciuri were the most prevalent species. Resistance to oxacillin (47.0% of the isolates), fusidic acid (33.8%), tiamulin (31.9%), penicillin (23.3%), tetracycline (15.8%), streptomycin (9.6%), erythromycin (7.0%), sulfonamides (5%), trimethoprim (4.3%), clindamycin (3.4%), kanamycin (2.4%), and gentamicin (2.4%) was detected. Resistance to oxacillin was attributed to the mecA gene in 9.7% of the oxacillin-resistant isolates. The remaining oxacillin-resistant CNS did not contain the mecC gene or mecA1 promoter mutations. The mecA gene was detected in Staphylococcus fleurettii, Staphylococcus epidermidis, Staph. haemolyticus, and Staph. xylosus. Resistance to tetracycline was attributed to the presence of tet(K) and tet(L), penicillin resistance to blaZ, streptomycin resistance to str and ant(6)-Ia, and erythromycin resistance to erm(C), erm(B), and msr. Resistance to tiamulin and fusidic acid could not be attributed to an acquired resistance gene. In total, 15.1% of the CNS isolates were multidrug resistant (i.e., resistant to 2 or more antimicrobials). The remaining CNS isolates were susceptible to antimicrobials commonly used in mastitis treatment. Methicillin-resistant CNS isolates were diverse, as determined by mecA gene sequence analysis, staphylococcal cassette chromosome mec typing, and pulsed-field gel electrophoresis. Arginine catabolic mobile element types 1 and 3 were detected in both methicillin-resistant and methicillin-susceptible Staph. epidermidis and were associated with sequence types ST59 and ST111. Because this study revealed the presence of multidrug-resistant CNS in a heterogeneous CNS population, we recommend antibiogram analysis of CNS in persistent infections before treatment with antimicrobials. Copyright © 2013 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Evaluation of Carbohydrate-Derived Fulvic Acid (CHD-FA) as a Topical Broad-Spectrum Antimicrobial for Drug-Resistant Wound Infections

DTIC Science & Technology

2015-10-01

resistant Klebsiella pneumoniae, Enterococcus faecium, Staphylococcus aureus, Methicillin- resistant Staphylococcus aureus (MRSA), Escherichia coli ...cutaneous wound model in rats with the drug resistant Gram negative bacteria Acinetobacter baumannii, Escherichia coli , Klebsiella pneumoniae and...bioburden reduction induced by CHD-FA was also observed in wounds infected with multidrug resistant E. coli and K. pneumoniae. To better assess wound

Effect of dual delivery of antibiotics (vancomycin and cefazolin) and BMP-7 from chitosan microparticles on Staphylococcus epidermidis and pre-osteoblasts in vitro.

PubMed

Mantripragada, Venkata P; Jayasuriya, Ambalangodage C

2016-10-01

The main aims of this manuscript are to: i) determine the effect of commonly used antibiotics to treat osteoarticular infections on osteoblast viability, ii) study the dual release of the growth factor (BMP-7) and antibiotics (vancomycin and cefazolin) from chitosan microparticles iii) demonstrate the bioactivity of the antibiotics released in vitro on Staphylococcus epidermidis. The novelty of this work is dual delivery of growth factor and antibiotic from the chitosan microparticles in a controlled manner without affecting their bioactivity. Cefazolin and vancomycin have different therapeutic concentrations for their action in vivo and therefore, two different concentrations of the drugs were used. Osteoblast cytotoxicity test concluded that cefazolin concentrations of 50 and 100μg/ml were found to have positive influence on osteoblast proliferation. A significant increase in osteoblast proliferation was observed in the presence of cefazolin and BMP-7 in comparison with BMP-7 alone group; indicating cefazolin might play a role in osteoblast proliferation. On the other hand, vancomycin concentration of 1000μg/ml was found to significantly reduce (p<0.01) osteoblast proliferation in comparison with controls. The microbial study indicated that cefazolin at a minimum concentration of 21.5μg/ml could inhibit ~85% growth of S. epidermidis, whereas vancomycin at a concentration of 30μg/ml was found to inhibit ~80% bacterial growth. Copyright © 2016 Elsevier B.V. All rights reserved.

Nanocomposite of polystyrene foil grafted with metallaboranes for antimicrobial activity

NASA Astrophysics Data System (ADS)

Benkocká, Monika; Kolářová, Kateřina; Matoušek, Jindřich; Semerádtová, Alena; Šícha, Václav; Kolská, Zdeňka

2018-05-01

The surface of polystyrene foil (PS) was chemically modified. Firstly, the surface was pre-treated with Piranha solution. The activated surface was grafted by selected amino-compounds (cysteamine, ethylenediamine or chitosan) and/or subsequently grafted with five members of inorganic metallaboranes. Selected surface properties were studied by using various methods in order to indicate significant changes before and after individual modification steps of polymer foil. Elemental composition of surface was conducted by using X-ray photoelectron spectroscopy, chemistry and polarity by infrared spectroscopy and by electrokinetic analysis, wettability by goniometry, surface morphology by atomic force microscopy. Antimicrobial tests were performed on individual samples in order to confirm antimicrobial impact. Our results show slight antibacterial activity of PS modified with SK5 for Escherichia coli in comparison with the rest of the tested borane. On the other hand molecules of all tested metallaboranes could easier pierce through bacterial cell of Staphylococcus epidermidis due to absence of outer membrane (phospholipid bilayer). Some borane grafted on PS surface embodies the strong activity for Staphylococcus epidermidis and also for Desmodesmus quadricauda growth inhibition.

Long-term release of antibiotics by carbon nanotube-coated titanium alloy surfaces diminish biofilm formation by Staphylococcus epidermidis.

PubMed

Hirschfeld, Josefine; Akinoglu, Eser M; Wirtz, Dieter C; Hoerauf, Achim; Bekeredjian-Ding, Isabelle; Jepsen, Søren; Haddouti, El-Mustapha; Limmer, Andreas; Giersig, Michael

2017-05-01

Bacterial biofilms cause a considerable amount of prosthetic joint infections every year, resulting in morbidity and expensive revision surgery. To address this problem, surface modifications of implant materials such as carbon nanotube (CNT) coatings have been investigated in the past years. CNTs are biologically compatible and can be utilized as drug delivery systems. In this study, multi-walled carbon nanotube (MWCNT) coated TiAl6V4 titanium alloy discs were fabricated and impregnated with Rifampicin, and tested for their ability to prevent biofilm formation over a period of ten days. Agar plate-based assays were employed to assess the antimicrobial activity of these surfaces against Staphylococcus epidermidis. It was shown that vertically aligned MWCNTs were more stable against attrition on rough surfaces than on polished TiAl6V4 surfaces. Discs with coated surfaces caused a significant inhibition of biofilm formation for up to five days. Therefore, MWCNT-modified surfaces may be effective against pathogenic biofilm formation on endoprostheses. Copyright © 2017 Elsevier Inc. All rights reserved.

Antimicrobial Activities of Three Medicinal Plants and Investigation of Flavonoids of Tripleurospermum disciforme.

PubMed

Tofighi, Zahra; Molazem, Maryam; Doostdar, Behnaz; Taban, Parisa; Shahverdi, Ahmad Reza; Samadi, Nasrin; Yassa, Narguess

2015-01-01

Rosa damascena, Tripleurospermum disciforme and Securigera securidaca were used as disinfectant agents and for treatment of some disease in folk medicine of Iran. The antimicrobial effects of different fractions of seeds extract of S. securidaca, petals extract of R. damascena and aerial parts extract of T. disciforme were examined against some gram positive, gram negative and fungi by cup plate diffusion method. The petroleum ether and chloroform fractions of S. securidaca showed antibacterial activities against Staphylococcus aureus and Pseudomonas aeruginosa, while its methanol fraction had no antibacterial effects. R. damascena petals extract demonstrated antibacterial activities against Bacillus cereus, Staphylococcus epidermidis, S. aureus and Pseudomonas aeruginosa. T. disciforme aerial parts extract exhibited antimicrobial effects only against S. aureus and S. epidermidis. None of the fractions had any antifungal activities. Therefore, present study confirmed utility of these plants as disinfectant agents. Six flavonoids were isolated from T. disciforme: Luteolin, Quercetin-7-O-glucoside, Kaempferol, Kaempferol-7-O-glucoside, Apigenin and Apigenin-7-O-glucoside. The flavonoids and the antimicrobial activity of T. disciforme are reported for the first time.

Antimicrobial Activities of Three Medicinal Plants and Investigation of Flavonoids of Tripleurospermum disciforme

PubMed Central

Tofighi, Zahra; Molazem, Maryam; Doostdar, Behnaz; Taban, Parisa; Shahverdi, Ahmad Reza; Samadi, Nasrin; Yassa, Narguess

2015-01-01

Rosa damascena, Tripleurospermum disciforme and Securigera securidaca were used as disinfectant agents and for treatment of some disease in folk medicine of Iran. The antimicrobial effects of different fractions of seeds extract of S. securidaca, petals extract of R. damascena and aerial parts extract of T. disciforme were examined against some gram positive, gram negative and fungi by cup plate diffusion method. The petroleum ether and chloroform fractions of S. securidaca showed antibacterial activities against Staphylococcus aureus and Pseudomonas aeruginosa, while its methanol fraction had no antibacterial effects. R. damascena petals extract demonstrated antibacterial activities against Bacillus cereus, Staphylococcus epidermidis, S. aureus and Pseudomonas aeruginosa. T. disciforme aerial parts extract exhibited antimicrobial effects only against S. aureus and S. epidermidis. None of the fractions had any antifungal activities. Therefore, present study confirmed utility of these plants as disinfectant agents. Six flavonoids were isolated from T. disciforme: Luteolin, Quercetin-7-O-glucoside, Kaempferol, Kaempferol-7-O-glucoside, Apigenin and Apigenin-7-O-glucoside. The flavonoids and the antimicrobial activity of T. disciforme are reported for the first time. PMID:25561928

The Effect of Zirconia in Hydroxyapatite on Staphylococcus epidermidis Growth.

PubMed

Siswomihardjo, Widowati; Sunarintyas, Siti; Tontowi, Alva Edy

2012-01-01

Synthetic hydroxyapatite (HA) has been widely used and developed as the material for bone substitute in medical applications. The addition of zirconia is needed to improve the strength of hydroxyapatite as the bone substitute. One of the drawbacks in the use of biomedical materials is the occurrence of biomaterial-centred infections. The recent method of limiting the presence of microorganism on biomaterials is by providing biomaterial-bound metal-containing compositions. In this case, S. epidermidis is the most common infectious organism in biomedical-centred infection. Objective. This study was designed to evaluate the effect of zirconia concentrations in hydroxyapatite on the growth of S. epidermidis. Methods and Materials. The subjects of this study were twenty hydroxyapatite discs, divided into four groups in which one was the control and the other three were the treatment groups. Zirconia powder with the concentrations of 20%, 30%, and 40% was added into the three different treatment groups. Scanning electron microscope analysis was performed according to the hydroxyapatite and hydroxyapatite-zirconia specimens. All discs were immersed into S. epidermidis culture for 24 hours and later on they were soaked into a medium of PBS. The cultured medium was spread on mannitol salt agar. After incubation for 24 hours at 37°C , the number of colonies was measured with colony counter. Data obtained were analyzed using the ANOVA followed by the pairwise comparison. Result. The statistical analysis showed that different concentrations of zirconia powder significantly influenced the number of S. epidermidis colony (P < 0.05) . Conclusion. The addition of zirconia into hydroxyapatite affected the growth of S. epidermidis. Hydroxyapatite with 20% zirconia proved to be an effective concentration to inhibit the growth of S. epidermidis colony.

The Effect of Zirconia in Hydroxyapatite on Staphylococcus epidermidis Growth

PubMed Central

Siswomihardjo, Widowati; Sunarintyas, Siti; Tontowi, Alva Edy

2012-01-01

Synthetic hydroxyapatite (HA) has been widely used and developed as the material for bone substitute in medical applications. The addition of zirconia is needed to improve the strength of hydroxyapatite as the bone substitute. One of the drawbacks in the use of biomedical materials is the occurrence of biomaterial-centred infections. The recent method of limiting the presence of microorganism on biomaterials is by providing biomaterial-bound metal-containing compositions. In this case, S. epidermidis is the most common infectious organism in biomedical-centred infection. Objective. This study was designed to evaluate the effect of zirconia concentrations in hydroxyapatite on the growth of S. epidermidis. Methods and Materials. The subjects of this study were twenty hydroxyapatite discs, divided into four groups in which one was the control and the other three were the treatment groups. Zirconia powder with the concentrations of 20%, 30%, and 40% was added into the three different treatment groups. Scanning electron microscope analysis was performed according to the hydroxyapatite and hydroxyapatite-zirconia specimens. All discs were immersed into S. epidermidis culture for 24 hours and later on they were soaked into a medium of PBS. The cultured medium was spread on mannitol salt agar. After incubation for 24 hours at 37°C , the number of colonies was measured with colony counter. Data obtained were analyzed using the ANOVA followed by the pairwise comparison. Result. The statistical analysis showed that different concentrations of zirconia powder significantly influenced the number of S. epidermidis colony (P < 0.05) . Conclusion. The addition of zirconia into hydroxyapatite affected the growth of S. epidermidis. Hydroxyapatite with 20% zirconia proved to be an effective concentration to inhibit the growth of S. epidermidis colony. PMID:22919390

Presence of Laminin Receptors in Staphylococcus aureus

NASA Astrophysics Data System (ADS)

Lopes, J. D.; Dos Reis, M.; Brentani, R. R.

1985-07-01

A characteristic feature of infection by Staphylococcus aureus is bloodstream invasion and widespread metastatic abscess formation. The ability to extravasate, which entails crossing the vascular basement membrane, appears to be critical for the organism's pathogenicity. Extravasation by normal and neoplastic mammalian cells has been correlated with the presence of specific cell surface receptors for the basement membrane glycoprotein laminin. Similar laminin receptors were found in Staphylococcus aureus but not in Staphylococcus epidermidis, a noninvasive pathogen. There were about 100 binding sites per cell, with an apparent binding affinity of 2.9 nanomolar. The molecular weight of the receptor was 50,000 and pI was 4.2. Eukaryotic laminin receptors were visualized by means of the binding of S. aureus in the presence of laminin. Prokaryotic and eukaryotic invasive cells might utilize similar, if not identical, mechanisms for invasion.

Efficacy of atmospheric pressure dielectric barrier discharge for inactivating airborne pathogens

DOE PAGES

Romero-Mangado, Jaione; Dey, Avishek; Diaz-Cartagena, Diana C.; ...

2017-07-05

Atmospheric pressure plasmas have gained attention in recent years for several environmental applications. This technology could potentially be used to deactivate airborne microorganisms, surface-bound microorganisms, and biofilms. Here, the authors explore the efficacy of the atmospheric pressure dielectric barrier discharge (DBD) to inactivate airborne Staphylococcus epidermidis and Aspergillus niger that are opportunistic pathogens associated with nosocomial infections. This technology uses air as the source of gas and does not require any process gas such as helium, argon, nitrogen, or hydrogen. Moreover, the effect of DBD was studied on aerosolized S. epidermidis and aerosolized A. niger spores via scanning electron microscopymore » (SEM). The morphology observed on the SEM micrographs showed deformations in the cellular structure of both microorganisms. Cell structure damage upon interaction with the DBD suggests leakage of vital cellular materials, which is a key mechanism for microbial inactivation. The chemical structure of the cell surface of S. epidermidis was also analyzed by near edge x-ray absorption fine structure spectroscopy before and after DBD exposure. Our results from surface analysis revealed that reactive oxygen species from the DBD discharge contributed to alterations on the chemistry of the cell membrane/cell wall of S. epidermidis.« less

Efficacy of atmospheric pressure dielectric barrier discharge for inactivating airborne pathogens

DOE Office of Scientific and Technical Information (OSTI.GOV)

Romero-Mangado, Jaione; Dey, Avishek; Diaz-Cartagena, Diana C.

Atmospheric pressure plasmas have gained attention in recent years for several environmental applications. This technology could potentially be used to deactivate airborne microorganisms, surface-bound microorganisms, and biofilms. Here, the authors explore the efficacy of the atmospheric pressure dielectric barrier discharge (DBD) to inactivate airborne Staphylococcus epidermidis and Aspergillus niger that are opportunistic pathogens associated with nosocomial infections. This technology uses air as the source of gas and does not require any process gas such as helium, argon, nitrogen, or hydrogen. Moreover, the effect of DBD was studied on aerosolized S. epidermidis and aerosolized A. niger spores via scanning electron microscopymore » (SEM). The morphology observed on the SEM micrographs showed deformations in the cellular structure of both microorganisms. Cell structure damage upon interaction with the DBD suggests leakage of vital cellular materials, which is a key mechanism for microbial inactivation. The chemical structure of the cell surface of S. epidermidis was also analyzed by near edge x-ray absorption fine structure spectroscopy before and after DBD exposure. Our results from surface analysis revealed that reactive oxygen species from the DBD discharge contributed to alterations on the chemistry of the cell membrane/cell wall of S. epidermidis.« less

Oxacilin-resistant Coagulase-negative staphylococci (CoNS) bacteremia in a general hospital at São Paulo city, Brasil

PubMed Central

d’Azevedo, P.A.; Secchi, C.; Antunes, A.L.S.; Sales, T.; Silva, F.M.; Tranchesi, R.; Pignatari, A.C.C.

2008-01-01

In the last decades, coagulase-negative staphylococci (CoNS), especially Staphylococcus epidermidis have become an important cause of bloodstream infections. In addition, rates of methicillin-resistance among CoNS have increased substantially, leading to the use of glicopeptides for therapy. The objective of this study was to evaluate eleven consecutives clinically relevant cases of oxacillin-resistant CoNS bacteremia in a general hospital localized in São Paulo city, Brazil. Five different species were identified by different phenotypic methods, including S. epidermidis (5), S. haemolyticus (3), S. hominis (1), S. warneri (1) and S. cohnii subsp urealyticus (1). A variety of Pulsed Field Gel Electrophoresis profiles was observed by macrorestriction DNA analysis in S. epidermidis isolates, but two of three S. haemolyticus isolates presented the same profile. These data indicated the heterogeneity of the CoNS isolates, suggesting that horizontal dissemination of these microorganisms in the investigated hospital was not frequent. One S. epidermidis and one S. haemolyticus isolates were resistant to teicoplanin and susceptible to vancomycin. The selective pressure due to the use of teicoplanin in this hospital is relevant. PMID:24031279

Epidemiology of Resistant Microbial Strains Among Different Groups of People (Healthy, Infected and Exposed to Animals)

ClinicalTrials.gov

2017-11-10

ESBL Producing E.Coli; ESBL Producing K.Pneumoniae; Multidrug Resistant P.Aeruginosa; Carbapenem Resistant P.Aeruginosa; Methicillin Resistant Staphylococcus Aureus (MRSA); Vancomycin (Glycopeptide) Resistant Enterococcus (VRE)

Vaccine potential of poly-1-6 beta-D-N-succinylglucosamine, an immunoprotective surface polysaccharide of Staphylococcus aureus and Staphylococcus epidermidis.

PubMed

Mckenney, D; Pouliot, K; Wang, Y; Murthy, V; Ulrich, M; Döring, G; Lee, J C; Goldmann, D A; Pier, G B

2000-09-29

Staphylococcus aureus and S. epidermidis are among the most common causes of nosocomial infection, and S. aureus is also of major concern to human health due to its occurrence in community-acquired infections. These staphylococcal species are also major pathogens for domesticated animals. We have previously identified poly-N-succinyl beta-1-6 glucosamine (PNSG) as the chemical form of the S. epidermidis capsular polysaccharide/adhesin (PS/A) which mediates adherence of coagulase-negative staphylococci (CoNS) to biomaterials, serves as the capsule for strains of CoNS that express PS/A, and is a target for protective antibodies. We have recently found that PNSG is made by S. aureus as well, where it is an environmentally regulated, in vivo-expressed surface polysaccharide and similarly serves as a target for protective immunity. Only a minority of fresh human clinical isolates of S. aureus elaborate PNSG in vitro but most could be induced to do so under specific in vitro growth conditions. However, by immunofluorescence microscopy, S. aureus cells in infected human sputa and lung elaborated PNSG. The ica genes, previously shown to encode proteins in CoNS that synthesize PNSG, were found by PCR in all S. aureus strains examined, and immunogenic and protective PNSG could be isolated from S. aureus. Active and passive immunization of mice with PNSG protected them against metastatic kidney infections after intravenous inoculation with eight phenotypically PNSG-negative S. aureus. Isolates recovered from kidneys expressed PNSG, but expression was lost with in vitro culture. Strong antibody responses to PNSG were elicited in S. aureus infected mice, and a PNSG-capsule was observed by electron microscopy on isolates directly plated from infected kidneys. PNSG represents a previously unidentified surface polysaccharide of S. aureus that is elaborated during human and animal infection and is a prominent target for protective antibodies.

Skin bacterial flora as a potential risk factor predisposing to late bacterial infection after cross-linked hyaluronic acid gel augmentation.

PubMed

Netsvyetayeva, Irina; Marusza, Wojciech; Olszanski, Romuald; Szyller, Kamila; Krolak-Ulinska, Aneta; Swoboda-Kopec, Ewa; Sierdzinski, Janusz; Szymonski, Zachary; Mlynarczyk, Grazyna

2018-01-01

Cross-linked hyaluronic acid (HA) gel is widely used in esthetic medicine. Late bacterial infection (LBI) is a rare, but severe complication after HA augmentation. The aim of this study was to determine whether patients who underwent the HA injection procedure and developed LBI had qualitatively different bacterial flora on the skin compared to patients who underwent the procedure without any complications. The study group comprised 10 previously healthy women with recently diagnosed, untreated LBI after HA augmentation. The control group comprised 17 healthy women who had a similar amount of HA injected with no complications. To assess the difference between the two groups, their skin flora was cultured from nasal swabs, both before and after antibiotic treatment in the study group. A significant increase in the incidence of Staphylococcus epidermidis was detected in the control group ( P =0.000) compared to the study group. The study group showed a significantly higher incidence of Staphylococcus aureus ( P =0.005), Klebsiella pneumoniae ( P =0.006), Klebsiella oxytoca ( P =0.048), and Staphylococcus haemolyticus ( P =0.048) compared to the control group. The bacterial flora on the skin differed in patients with LBI from the control group. The control group's bacterial skin flora was dominated by S. epidermidis . Patients with LBI had a bacterial skin flora dominated by potentially pathogenic bacteria.

Development of extract library from indonesian biodiversity: exploration of antibacterial activity of mangrove bruguiera cylindrica leaf extracts

NASA Astrophysics Data System (ADS)

Audah, K. A.; Amsyir, J.; Almasyhur, F.; Hapsari, A. M.; Sutanto, H.

2018-03-01

Antibacterial drugs derived from natural sources play significant roles in the prevention and treatment of bacterial infections since antibiotics have become less effective against many infectious diseases. Mangroves are very potential natural antibacterial sources among great numbers of wild medicinal plants. Bruguiera cylindrica is one of the many mangroves species which spread along Indonesian coastline. The aim of this study was to explore the antibacterial activity of B. cylindrica wet and dried leaf extracts. The wet extracts study was conducted with three different solvents system (water, ethanol, and n-Hexane) against Escherichia coli and Staphylococcus aureus. While, the dried extracts study was conducted with four different solvents system (water, ethanol, chloroform and n-Hexane) against three types of bacteria, Escherichia coli, Staphylococcus epidermidis and Staphylococcus aureus. The study showed that ethanol was the best solvent for extraction of phenolic and flavonoid. Antibacterial actitivity was measured by zone of inhibition which obtained from agar-disk diffusion method. The widest area of zone of inhibition was showed by wet extracts with ethanol against S. aureus and E. coli are 14.30 and 13.30 mm, respectively. While, the zone of inhibition dried extracts with ethanol against S. aureus, S. epidermidis and E. coli are 9.32, 6.59 and 6.20 mm, respectively. In conclusion, both type of extracts showed significant antibacterial activity against gram-positive bacteria as crude extracts.

Prospective evaluation of external ocular microbial growth and aqueous humor contamination during cataract surgery.

PubMed

Tervo, T; Ljungberg, P; Kautiainen, T; Puska, P; Lehto, I; Raivio, I; Järvinen, E; Kuusela, P; Tarkkanen, A

1999-01-01

To analyze the route of aqueous humor contamination leading to the development of postoperative endophthalmitis. Department of Ophthalmology, University of Helsinki, Finland. Forty-nine eyes of 49 patients (31 having phacoemulsification and 18 extracapsular cataract extraction [ECCE]) participated in the study. Four bacterial cultures were taken: preoperative conjunctival swab, lid margin culture, intraoperative lacrimal lake sample, and immediate postoperative anterior chamber fluid sample. Preoperative lid margin cultures were positive in 59.2% of eyes, conjunctival cultures in 69.4%, and lacrimal lake cultures in 24.9%. Four aqueous humor samples (8.2%) showed bacterial growth in the anterior chamber aspirate: 3 in the phacoemulsification and 1 in the ECCE group. The bacteria isolated in this study, Staphylococcus epidermidis and Propionibacterium acnes (2 positive isolates each) were sensitive to the preoperative topical antibiotics used. No aqueous humor sample or any from other locations showed gram-negative microbe growth. The most frequently recovered microbes in all samples collected from the 3 other sources were S epidermidis and other coagulase-negative staphylococcus species, followed by P acnes and other propionibacterium species. Staphylococcus aureus, and diptheroids. The ocular surface significantly contributed to the transmission of microbes into the eye during cataract surgery. These microbes could not be eradicated by topical preoperative antibiotics. However, no patient developed postoperative endophthalmitis. Natural defense mechanisms appear to fend off a minor inoculum with these microbes of relatively low pathogenicity.

Distribution of non-aureus staphylococci species in udder quarters with low and high somatic cell count, and clinical mastitis.

PubMed

Condas, Larissa A Z; De Buck, Jeroen; Nobrega, Diego B; Carson, Domonique A; Roy, Jean-Philippe; Keefe, Greg P; DeVries, Trevor J; Middleton, John R; Dufour, Simon; Barkema, Herman W

2017-07-01

The effect of non-aureus staphylococci (NAS) in bovine mammary health is controversial. Overall, NAS intramammary infections (IMI) increase somatic cell count (SCC), with an effect categorized as mild, mostly causing subclinical or mild to moderate clinical mastitis. However, based on recent studies, specific NAS may affect the udder more severely. Some of these apparent discrepancies could be attributed to the large number of species that compose the NAS group. The objectives of this study were to determine (1) the SCC of quarters infected by individual NAS species compared with NAS as a group, culture-negative, and major pathogen-infected quarters; (2) the distribution of NAS species isolated from quarters with low SCC (<200,000 cells/mL) and high SCC (≥200,000 cells/mL), and clinical mastitis; and (3) the prevalence of NAS species across quarters with low and high SCC. A total of 5,507 NAS isolates, 3,561 from low SCC quarters, 1,873 from high SCC quarters, and 73 from clinical mastitis cases, were obtained from the National Cohort of Dairy Farms of the Canadian Bovine Mastitis Research Network. Of quarters with low SCC, high SCC, or clinical mastitis, 7.6, 18.5, and 4.3% were NAS positive, respectively. The effect of NAS IMI on SCC was estimated using mixed-effect linear regression; prevalence of NAS IMI was estimated using Bayesian analyses. Mean SCC of NAS-positive quarters was 70,000 cells/mL, which was higher than culture-negative quarters (32,000 cells/mL) and lower than major pathogen-positive quarters (129,000 to 183,000 cells/mL). Compared with other NAS species, SCC was highest in quarters positive for Staphylococcus capitis, Staphylococcus gallinarum, Staphylococcus hyicus, Staphylococcus agnetis, or Staphylococcus simulans. In NAS-positive quarters, Staphylococcus xylosus (12.6%), Staphylococcus cohnii (3.1%), and Staphylococcus equorum (0.6%) were more frequently isolated from quarters with low SCC than other NAS species, whereas Staphylococcus sciuri (14%) was most frequently isolated from clinical mastitis cases. Finally, in NAS-positive quarters, Staphylococcus chromogenes, S. simulans, Staphylococcus epidermidis, and Staphylococcus haemolyticus were isolated with similar frequency from among low SCC and high SCC quarters and clinical mastitis cases. Staphylococcus chromogenes, S. simulans, S. xylosus, S. haemolyticus, S. epidermidis, S. agnetis, Staphylococcus arlettae, S. capitis, S. gallinarum, S. sciuri, and Staphylococcus warneri were more prevalent in high than in low SCC quarters. Because the NAS are a large, heterogeneous group, considering them as a single group rather than at the species, or even subspecies level, has undoubtedly contributed to apparent discrepancies among studies as to their distribution and importance in IMI and mastitis. Copyright © 2017 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Identification of Major Sequence Types among Multidrug-Resistant Staphylococcus epidermidis Strains Isolated from Infected Eyes and Healthy Conjunctiva

PubMed Central

Jena, Smrutiti; Panda, Sasmita; Nayak, Kinshuk C.; Singh, Durg V.

2017-01-01

We examined the presence of virulence and antibiotic resistance genes, SCCmec types and determined the genomic diversity among ocular S. epidermidis isolates (patients-23, healthy controls-29). PCR determined the presence of antibiotic resistance genes, virulence genes and SCCmec types among all isolates. MLST and PFGE determined the genomic relatedness among them. All isolates of S. epidermidis showed resistance to at least one class of antibiotics of which 48 isolates were multidrug resistant and carried ARGs. Thirty-five isolates were methicillin resistant and carried mecA gene. Majority of the isolates were resistant to fluoroquinolones and showed mutation in gyrA, parC, and parE genes, however, few isolates showed additional novel mutations in parC gene. Of the MRSE strains, 17 strains carried SCCmec type IV, four type V, two type II, and two UT4. Seven strains carried novel combination of ccr complex and SCCmercury element, not reported earlier. All the S. epidermidis strains harbored icaA and icaD genes, 47 carried ACME operon, and 50 contained IS256. A noteworthy finding was the presence of ST179 among 43% of infected eye isolates an observation rarely reported among S. epidermidis. PFGE and MLST analysis showed genomic diversity among them. Statistical analysis suggests that few healthy conjunctiva isolates had characteristics similar to infected eye isolates. S. epidermidis strains carrying mecA gene are multidrug resistant, virulent and diverse irrespective of sources of isolation. IS256 cannot be used as marker to differentiate isolates of infected eye from healthy conjunctiva. PMID:28824564

Evidence for Horizontal Gene Transfer in Evolution of Elongation Factor Tu in Enterococci

PubMed Central

Ke, Danbing; Boissinot, Maurice; Huletsky, Ann; Picard, François J.; Frenette, Johanne; Ouellette, Marc; Roy, Paul H.; Bergeron, Michel G.

2000-01-01

The elongation factor Tu, encoded by tuf genes, is a GTP binding protein that plays a central role in protein synthesis. One to three tuf genes per genome are present, depending on the bacterial species. Most low-G+C-content gram-positive bacteria carry only one tuf gene. We have designed degenerate PCR primers derived from consensus sequences of the tuf gene to amplify partial tuf sequences from 17 enterococcal species and other phylogenetically related species. The amplified DNA fragments were sequenced either by direct sequencing or by sequencing cloned inserts containing putative amplicons. Two different tuf genes (tufA and tufB) were found in 11 enterococcal species, including Enterococcus avium, Enterococcus casseliflavus, Enterococcus dispar, Enterococcus durans, Enterococcus faecium, Enterococcus gallinarum, Enterococcus hirae, Enterococcus malodoratus, Enterococcus mundtii, Enterococcus pseudoavium, and Enterococcus raffinosus. For the other six enterococcal species (Enterococcus cecorum, Enterococcus columbae, Enterococcus faecalis, Enterococcus sulfureus, Enterococcus saccharolyticus, and Enterococcus solitarius), only the tufA gene was present. Based on 16S rRNA gene sequence analysis, the 11 species having two tuf genes all have a common ancestor, while the six species having only one copy diverged from the enterococcal lineage before that common ancestor. The presence of one or two copies of the tuf gene in enterococci was confirmed by Southern hybridization. Phylogenetic analysis of tuf sequences demonstrated that the enterococcal tufA gene branches with the Bacillus, Listeria, and Staphylococcus genera, while the enterococcal tufB gene clusters with the genera Streptococcus and Lactococcus. Primary structure analysis showed that four amino acid residues encoded within the sequenced regions are conserved and unique to the enterococcal tufB genes and the tuf genes of streptococci and Lactococcus lactis. The data suggest that an ancestral streptococcus or a streptococcus-related species may have horizontally transferred a tuf gene to the common ancestor of the 11 enterococcal species which now carry two tuf genes. PMID:11092850

Continuous monitoring of bacterial biofilm growth using uncoated Thickness-Shear Mode resonators

NASA Astrophysics Data System (ADS)

Castro, P.; Resa, P.; Durán, C.; Maestre, J. R.; Mateo, M.; Elvira, L.

2012-12-01

Quartz Crystal Microbalances (QCM) were used to nondestructively monitor in real time the microbial growth of the bacteria Staphylococcus epidermidis (S. epidermidis) in a liquid broth. QCM, sometimes referred to as Thickness-Shear Mode (TSM) resonators, are highly sensitive sensors not only able to measure very small mass, but also non-gravimetric contributions of viscoelastic media. These devices can be used as biosensors for bacterial detection and are employed in many applications including their use in the food industry, water and environment monitoring, pharmaceutical sciences and clinical diagnosis. In this work, three strains of S. epidermidis (which differ in the ability to produce biofilm) have been continuously monitored using an array of piezoelectric TSM resonators, at 37 °C in a selective culturing media. Microbial growth was followed by measuring the changes in the crystal resonant frequency and bandwidth at several harmonics. It was shown that microbial growth can be monitored in real time using multichannel and multiparametric QCM sensors.

Prevention and Management of Infections Associated With Burns in the Combat Casualty

DTIC Science & Technology

2008-03-01

even including staff members, to detect “carriers” of such organisms as methicillin - resistant S. aureus (MRSA) and drug- resistant gram-negatives.80–83...Lilly HA, Lowbury EJ. Antibiotic resistance of Staphylococcus aureus in a burns unit after stopping routine prophylaxis with erythromycin. J...nosocomial transmission of multidrug- resistant strains of Staphylococcus aureus and Enterococcus. Infect Control Hosp Epi. 2003;24:362–386. 89. Siegel JD

21 CFR 520.90b - Ampicillin trihydrate tablets.

Code of Federal Regulations, 2012 CFR

2012-04-01

... mirabilis, and Pasteurella spp., urinary tract infections (cystitis) due to Streptococcus spp., Staphylococcus spp., E., coli, P. mirabilis, and Enterococcus spp.; gastrointestinal infections due to... treatment of infections caused by susceptible organisms as follows: Upper respiratory infections...

Moxifloxacin superior to cefuroxime in reducing bacterial adhesion of Staphylococcus epidermidis on hydrophobic intraocular lenses.

PubMed

Benbouzid, Fathalah; Kodjikian, Laurent; Hartmann, Daniel; Renaud, François; Baillif, Stéphanie

2016-02-01

To compare the anti-adhesive effect of cefuroxime and moxifloxacin on the primary attachment phase of Staphylococcus epidermidis on hydrophobic acrylic intraocular lenses (IOLs). Forty hydrophobic acrylic IOLs were used. Two groups of IOLs were soaked in a moxifloxacin (Mox-T1: 0.5 mg/0.1 ml) or a cefuroxime (Cef-T1: cefuroxime 1 mg/0.1 ml) solution before incubation in a S. epidermidis bacterial suspension. Two other groups were incubated in the bacterial suspension before antibiotics (Cef-T2 and Mox-T2) were added. The control group (Ctrl) consisted of IOLs incubated in the bacterial suspension. After incubation, IOLs were sonicated and vortexed. The resultant suspension was spread over a nutritive agar plate. Bacterial colonies were counted after 24 hr of incubation. Mean number of colony-forming units per IOL was Cef-T1: 184 × 10(3) (SE: 5.24; SD: 28.21), Cef-T2: 117 × 10(3) (SE: 5.74; SD: 30.37), Mox-T1: 1.27 × 10(3) (SE: 0.12; SD: 0.61), Mox-T2: 25 × 10(3) (SE:1.98; SD: 9.72) and Ctrl: 361 × 10(3) (SE: 26.9; SD: 107.6). The number of adhering bacteria did not vary whether cefuroxime was added before or after IOL incubation in the bacterial suspension (p = 0.132). Moxifloxacin was more effective in reducing the number of adhering bacteria when used before IOL incubation (p < 0.001). Overall for T1 and T2, moxifloxacin was more effective than cefuroxime in reducing bacterial adhesion on IOLs (p < 0.001). Moxifloxacin and cefuroxime significantly reduced S. epidermidis adhesion on hydrophobic acrylic IOLs. The anti-adhesive effect was superior with moxifloxacin. © 2015 Acta Ophthalmologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.

Changes in ocular flora in eyes exposed to ophthalmic antibiotics.

PubMed

Dave, Sarita B; Toma, Hassanain S; Kim, Stephen J

2013-05-01

To determine changes in ocular flora in individuals repeatedly exposed to topical macrolide or fluoroquinolone antibiotics. Prospective, controlled, longitudinal study with 1-year follow-up. Forty-eight eyes of 24 patients undergoing serial unilateral intravitreal injection for choroidal neovascularization. Patients received 4 consecutive monthly unilateral intravitreal injections and were then treated as needed. Each patient was randomized to 1 of 4 antibiotics (azithromycin 1%, gatifloxacin 0.3%, moxifloxacin 0.5%, ofloxacin 0.3%) and used only their assigned antibiotic for 4 days after each injection. Conjunctival cultures of the treated eye and untreated fellow eye (control) were taken at baseline and before each injection. All bacterial isolates were tested for antibiotic susceptibility to 16 different antibiotics using the Kirby-Bauer disc diffusion technique. Changes in bacteria composition of the conjunctiva over time. In azithromycin-treated eyes, Staphylococcus epidermidis and Staphylococcus aureus accounted for 54.5% and 18.2% of cultured isolates, respectively, at baseline and 90.9% (P<0.01) and 4.5% (P<0.01), respectively, after azithromycin exposure. In fluoroquinolone-treated eyes, 45.7% and 6.5% of cultured isolates at baseline were S epidermidis and S aureus, respectively, but these percentages increased to 63.4% (P<0.03) and 13% (P = 0.24), respectively, after fluoroquinolone exposure. In contrast, the percentage of gram-negative species decreased from 8.7% at baseline to 1.6% (P<0.05) in fluoroquinolone-treated eyes. The percentage of S epidermidis isolated from azithromycin-treated eyes was significantly greater when compared with fellow control eyes (P<0.01) or fluoroquinolone-treated eyes (P<0.01). The percentage of S epidermidis isolated from the conjunctival surface significantly increases after repeated exposure to azithromycin and to a lesser degree fluoroquinolone antibiotics at the expense of other commensal flora. The author(s) have no proprietary or commercial interest in any materials discussed in this article. Copyright © 2013 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.

[Studies on the growth and reproduction of bacterial communities on structural materials of the international space station].

PubMed

Rakova, N M; Svistunova, Iu V; Novikova, N D

2005-01-01

Probability of microbial growth and reproduction on the ISS interior and equipment materials varying in chemical composition was studied with the strains of Bacillus subtilis, Staphylococcus epidermidis, Staphylococcus saprophyticus, Pseudomonas putida etc. sampled from the ISS environment. Controls were ground reference strains of same bacterial species. Based on our results, some of the microorganisms are able to survive and proliferate on structural materials; the ability was greater in space isolates as compared with their ground analogs. The greatest ability to grow and proliferate on materials was demonstrated by Bacillus subtilis.

[Method and procedures in bacteriological study of necrotic teeth].

PubMed

Rodríguez-Ponce, A; López Campos, A; López Paz, J; Pazos Sierra, R

1991-01-01

Research was conducted of 160 radicular canals with necrotic pulp. Results of different bacteriological analyses are presented. Culture analyses in aerobic and anaerobic media, resulted in the isolation of Staphylococcus Epidermidis, Streptococcus Viridans and Corynebacterium sp in the group studied, as the most frequent bacteria. There was no evidence of a specific germ linked with the pulp necrosis.

Repurposing Clinical Molecule Ebselen to Combat Drug Resistant Pathogens.

PubMed

Thangamani, Shankar; Younis, Waleed; Seleem, Mohamed N

2015-01-01

Without a doubt, our current antimicrobials are losing the battle in the fight against newly-emerged multidrug-resistant pathogens. There is a pressing, unmet need for novel antimicrobials and novel approaches to develop them; however, it is becoming increasingly difficult and costly to develop new antimicrobials. One strategy to reduce the time and cost associated with antimicrobial innovation is drug repurposing, which is to find new applications outside the scope of the original medical indication of the drug. Ebselen, an organoselenium clinical molecule, possesses potent antimicrobial activity against clinical multidrug-resistant Gram-positive pathogens, including Staphylococcus, Streptococcus, and Enterococcus, but not against Gram-negative pathogens. Moreover, the activity of ebselen against Gram-positive pathogens exceeded those activities determined for vancomycin and linezolid, drugs of choice for treatment of Enterococcus and Staphylococcus infections. The minimum inhibitory concentrations of ebselen at which 90% of clinical isolates of Enterococcus and Staphylococcus were inhibited (MIC90) were found to be 0.5 and 0.25 mg/L, respectively. Ebselen showed significant clearance of intracellular methicillin-resistant S. aureus (MRSA) in comparison to vancomycin and linezolid. We demonstrated that ebselen inhibits the bacterial translation process without affecting mitochondrial biogenesis. Additionally, ebselen was found to exhibit excellent activity in vivo in a Caenorhabditis elegans MRSA-infected whole animal model. Finally, ebselen showed synergistic activities with conventional antimicrobials against MRSA. Taken together, our results demonstrate that ebselen, with its potent antimicrobial activity and safety profiles, can be potentially used to treat multidrug resistant Gram-positive bacterial infections alone or in combination with other antibiotics and should be further clinically evaluated.

Evaluation of the Biotyper MALDI-TOF MS system for identification of Staphylococcus species.

PubMed

Zhu, Wenming; Sieradzki, Krzysztof; Albrecht, Valerie; McAllister, Sigrid; Lin, Wen; Stuchlik, Olga; Limbago, Brandi; Pohl, Jan; Kamile Rasheed, J

2015-10-01

The Bruker Biotyper MALDI-TOF MS (Biotyper) system, with a modified 30 minute formic acid extraction method, was evaluated by its ability to identify 216 clinical Staphylococcus isolates from the CDC reference collection comprising 23 species previously identified by conventional biochemical tests. 16S rDNA sequence analysis was used to resolve discrepancies. Of these, 209 (96.8%) isolates were correctly identified: 177 (84.7%) isolates had scores ≥2.0, while 32 (15.3%) had scores between 1.70 and 1.99. The Biotyper identification was inconsistent with the biochemical identification for seven (3.2%) isolates, but the Biotyper identifications were confirmed by 16S rDNA analysis. The distribution of low scores was strongly species-dependent, e.g. only 5% of Staphylococcus epidermidis and 4.8% of Staphylococcus aureus isolates scored below 2.0, while 100% of Staphylococcus cohnii, 75% of Staphylococcus sciuri, and 60% of Staphylococcus caprae produced low but accurate Biotyper scores. Our results demonstrate that the Biotyper can reliably identify Staphylococcus species with greater accuracy than conventional biochemicals. Broadening of the reference database by inclusion of additional examples of under-represented species could further optimize Biotyper results. Published by Elsevier B.V.

[Clinical analysis for patients with continuous ambulatory peritoneal dialysis associated peritonitis].

PubMed

Liu, Jian; Huang, Xun; Liu, Yao; Xu, Hui; Gong, Rui'e; Li, Chunhui

2016-12-28

To analyze the clinical characteristics of continuous ambulatory peritoneal dialysis (CAPD) associated peritonitis in the tertiary hospitals and to discuss the preventive and therapeutic strategy.
 Methods: The clinical characteristics, pathogens, resistance and outcomes of 126 CAPD associated peritonitis in 104 patients from Jan, 2013 to June, 2016, were retrospectively analyzed.
 Results: Among the patients, the incidence rates of abdominal pain, fever, diarrhea and emesis were 104 (82.54%), 56 (44.44%), 49 (38.89%), and 31 (23.60%), respectively. Among them, 88 patients suffered peritonitis once, other 16 patients suffered multiple peritonitis or recurrent peritonitis for 38 times. Among the 38 times, the numbers for recurrent, repeated or catheter-associated peritonitis were 2, 2, or 3, respectively. Peritoneal fluids from 103 cases were cultured, and 64 cases were positive in bacteria, with a rate of 62.14%. A total of 70 strains of bacteria were separated, including 42 strains of gram-positive bacteria, 21 strains of gram-negative bacteria, and 7 strains of fungus. The most common gram-positive pathogens were Staphylococcus epidermidis, Enterococcus faecalis and Staphylococcus haemolyticus, while Escherichia coli, Klebsiella pneumoniae and Klebsiella pneumoniae were the most common gram-negative bacteria. Candida albicans was the major fungal pathogens. Gram-positive cocci showed resistance to gentamycin, levofloxacin, moxifloxacin, vancomycin and linezolid, with a rate at 20.00%, 36.11%, 5%, 0%, and 0%, respectively. The gram-negative bacilli were resistent to cefoperazone/sulbactam, gentamycin, cephazolin, and ceftazidime, with a rate at 6.25%, 10.53%, 64.29%, and 15.38%, respectively. There were no imipenem, amikacin, piperacillin/tazobactam-resistant strains were found.
 Conclusion: The most common pathogen causing CAPD associated peritonitis is gram-positive bacteria. It is crucial to take the anti-infection therapy for CAPD associated peritonitis early. The positive rates for bacterial culture need to be enhanced through improvement of methods. At the same time, doctors could improve the outcome of CAPD associated peritonitis by adjusting the medication according to the drug sensitivity results.

Antibacterial properties of 2% lidocaine and reduced rate of endophthalmitis after intravitreal injection.

PubMed

Tustin, Aaron; Kim, Stephen J; Chomsky, Amy; Hubbard, G Baker; Sheng, Jinsong

2014-05-01

To determine whether the application of subconjunctival 2% lidocaine/0.1% methylparaben for anesthesia may reduce rates of endophthalmitis after intravitreal (IVT) injection. We performed in vitro experiments to determine the antibacterial properties of 2% lidocaine/0.1% methylparaben (lidocaine) against causative organisms of endophthalmitis. Isolates of Staphylococcus aureus, Staphylococcus epidermidis, and Streptococcus viridans from patients with endophthalmitis were incubated with or without lidocaine. Aliquots (100 µL) were plated on Mueller-Hinton (S. aureus and S. epidermidis) or blood agar plates (S. viridans) at 0, 10, 30, 120, and 240 minutes, and colonies were counted after 24 hours. A retrospective review of 15,042 IVT injections was performed from January 2004 to February 2011 to determine the rate of endophthalmitis with or without application of subconjunctival lidocaine for anesthesia. Lidocaine demonstrated rapid bactericidal effects against all 3 organisms. After 10 minutes of exposure, there was approximately a 90% (P < 0.01), 95% (P < 0.001), and 92% (P < 0.001) reduction in colony forming units when compared with time 0 for S. aureus, S. epidermidis, and S. viridans, respectively. Complete elimination of colony forming units occurred at subsequent time points for each organism in contrast to logarithmic increase for control plates. There were a total of 0 cases of endophthalmitis of 6,853 IVT injections performed with subconjunctival lidocaine and 8 cases of endophthalmitis of 8,189 (0.1%) IVT injections performed with other methods of anesthesia (P = 0.03). Application of subconjunctival 2% lidocaine/0.1% methylparaben for anesthesia may reduce the incidence of endophthalmitis after IVT injection.

Fluctuation of Bacteria on Bleb Surface After Trabeculectomy With Adjunctive Mitomycin C.

PubMed

Takahashi, Nobumichi; Sawada, Akira; Mochizuki, Kiyofumi; Katada, Toshihiko; Yamamoto, Tetsuya

2016-05-01

To determine whether the bacterial and floral patterns on the bleb surface are affected by the season in eyes that had undergone trabeculectomy with adjunctive mitomycin C. Forty-four glaucoma patients who had an avascular or a hypovascular cystic filtering bleb were studied. Swabs of the bleb surface were taken 4 times in 1 year. The samples were cultured, and all organisms isolated were identified and tested for antibiotic sensitivity and resistance. Of the 176 specimens, 48 tested positive in cultures. Out of the 44 glaucoma eyes that had undergone trabeculectomy, 30 (68.2%) eyes were culture positive. A total of 58 strains were isolated. The organisms isolated were 22 strains of Staphylococcus epidermidis, 21 strains of Propionibacterium acnes, 8 strains of Corynebacterium sp., 5 strains of Staphylococcus sp., and 1 strain of both Neisseria sp., and Candida parapsilosis. Fifteen eyes had a positive culture ≥2 times, and in 10 of these eyes, the same strain was isolated. There was no resistance to vancomycin by S. epidermidis, P. acnes, and Corynebacterium sp. All of the isolates of S.epidermidis were sensitive to minocycline and amikacin. The rate of bacterial detection in the spring was 13.6%, summer was 20.5%, autumn was 45.5%, and winter was 29.5%. The increase in the incidence of bacterial presence during autumn was significant (P=0.006; the Fisher exact probability test). It is not rare to detect the bacterial organisms on the bleb surface in glaucomatous eyes that had undergone trabeculectomy. The prevalence varied with the season and was highest in the autumn.

Bacterial Coaggregation and Cohesion Among Isolates From Contact Lens Cases.

PubMed

Datta, Ananya; Stapleton, Fiona; Willcox, Mark D P

2018-06-01

The aim of this study was to examine cohesion, coaggregation, and coculture between bacteria commonly isolated from contact lens cases. Staphylococcus epidermidis, Staphylococcus haemolyticus, Micrococcus luteus, and Acinetobacter radioresistens (two strains each) isolated from contact lens cases of two asymptomatic wearers were used in this study. In the cohesion assay, bacteria were grown, washed, and examined by incubating lens cases with two different types of bacteria sequentially and assessing the number of adhered cells of each isolate. The ability of isolates to interfere with the growth of other isolates was tested by growing strains in cocultures for 24 hours and determining the numbers of cells of individual strains. For coaggregation, equal proportions of two bacterial suspensions were mixed and allowed to coaggregate for 24 hours. Inhibition of coaggregation was tested by the addition of lactose (0.06 M) or sucrose (0.06 M) or pronase. The initial adhesion of M. luteus or A. radioresistens significantly (P < 0.05) enhanced the subsequent adhesion of the staphylococci. The addition of A. radioresistens in liquid media significantly (P < 0.05) enhanced the growth of staphylococci. S. epidermidis or S. haemolyticus coaggregated with M. luteus or A. radioresistens. The degree of coaggregation varied between 30% and 54%. The highest coaggregation (54% ± 5%) was seen between A. radioresistens 22-1 and S. epidermidis 22-1, isolated from the same lens case. Only lactose or sucrose treatment of staphylococci could partly inhibit coaggregation of some pairs. Coaggregation, cohesion, and growth promotion may facilitate the process of bacterial colonization of contact lens cases.

Co-infection of methicillin-resistant Staphylococcus epidermidis, methicillin-resistant Staphylococcus aureus and extended spectrum β-lactamase producing Escherichia coli in bovine mastitis--three cases reported from India.

PubMed

Bandyopadhyay, Samiran; Samanta, Indranil; Bhattacharyya, Debaraj; Nanda, Pramod Kumar; Kar, Debasish; Chowdhury, Jayanta; Dandapat, Premanshu; Das, Arun Kumar; Batul, Nayan; Mondal, Bimalendu; Dutta, Tapan Kumar; Das, Gunjan; Das, Bikash Chandra; Naskar, Syamal; Bandyopadhyay, Uttam Kumar; Das, Suresh Chandra; Bandyopadhyay, Subhasish

2015-03-01

Emergence of antimicrobial resistance among bovine mastitis pathogens is the major cause of frequent therapeutic failure and a cause of concern for veterinary practitioners. This study describes intra-mammary infection of methicillin-resistant Staphylococcus epidermidis (MRSE), methicillin-resistant Staphylococcus aureus (MRSA) and extended spectrum β-lactamase (ESBL) producing Escherichia coli in two Holstein Friesian crossbred cows with subclinical mastitis and one non-descript cow with clinical mastitis in two different districts of West Bengal, India. In total, three MRSE, one MRSA and three ESBL producing E. coli were isolated from these cases. Both the crossbreds were detected with MRSE (HFSE1 and HFSE2) and ESBL producing E. coli (HFEC1 and HFEC2), whereas, simultaneous infection of three pathogens viz. MRSA (NDSA1), MRSE (NDSE1) and ESBL producing E. coli (NDEC1) was found in the non-descript cow. The methicillin-resistant isolates possessed mecA gene and exhibited resistance to various antibiotics such as amikacin, tetracycline and glycopeptides. The ESBL producers were positive for blaCTX-M and blaTEM genes; in addition, HFEC1 and HFEC2 were positive for blaSHV and possessed the genes for class I integron (int1), sulphonamide resistance (sul1), quinolone resistance (qnrS) and other virulence factors (papC, iucD and ESTA1). All the ESBL producers exhibited resistance to a variety of antibiotics tested including third- and fourth-generation cephalosporins and were also intermediately resistant to carbapenems. This is the first ever report on simultaneous occurrence of MRSE, MRSA and ESBL producing E. coli in bovine mastitis indicating a major concern for dairy industry and public health as well.

Vancomycin Ophthalmic Ointment 1% for methicillin-resistant Staphylococcus aureus or methicillin-resistant Staphylococcus epidermidis infections: a case series

PubMed Central

Sotozono, Chie; Fukuda, Masahiko; Ohishi, Masao; Yano, Keiko; Origasa, Hideki; Saiki, Yoshinori; Shimomura, Yoshikazu; Kinoshita, Shigeru

2013-01-01

Objectives To investigate the efficacy and safety of Vancomycin Ophthalmic Ointment 1% (Toa Pharmaceutical Co., Ltd, Toyama, Japan) in patients with external ocular infections caused by methicillin-resistant Staphylococcus aureus (MRSA) or methicillin-resistant Staphylococcus epidermidis (MRSE). Design A case series. Setting This study was a multicentre, open-label, uncontrolled study in Japan approved as orphan drug status. Participants Patients with MRSA or MRSE external ocular infections unresponsive to the treatment of fluoroquinolone eye drops. Interventions Vancomycin Ophthalmic Ointment 1% was administered four times daily. Primary and secondary outcome measures The subjective and objective clinical scores and bacterial cultures were collected at days 0 (baseline), 3, 7 and 14. The primary outcome was clinical response evaluation (efficacy rate) determined as complete response, partial response, no response and worsening. Secondary outcome was the eradication of the bacteria. Safety was assessed by adverse events including cases in which neither MRSA nor MRSE was detected. Results Twenty-five cases with MRSA (20) or MRSE (5) infections were enrolled. Of these 25 cases, 4 discontinued the treatment due to the negative results for bacterial culture during screening or at baseline. Of the 21 cases with conjunctivitis (14), blepharitis (3), meibomitis (1), dacryocystitis (2) or keratitis (1), 14 (66.7%) cases were evaluated as being excellently (complete response, 2 cases) or well (partial response, 12 cases) treated. The eradication rates were 68.4% in MRSA (13 of 19 cases) and 100% in MRSE (2 of 2 cases). Ten adverse events occurred in 7 (28.0%) of 25 cases at the local administration site. Conclusions Vancomycin Ophthalmic Ointment 1% was considered to be useful for the treatment of intractable ocular MRSA/MRSE infections. PMID:23364319

Short communication: Identification of coagulase-negative staphylococcus species from goat milk with the API Staph identification test and with transfer RNA-intergenic spacer PCR combined with capillary electrophoresis.

PubMed

Koop, G; De Visscher, A; Collar, C A; Bacon, D A C; Maga, E A; Murray, J D; Supré, K; De Vliegher, S; Haesebrouck, F; Rowe, J D; Nielen, M; van Werven, T

2012-12-01

Coagulase-negative staphylococci (CNS) are the most commonly isolated bacteria from goat milk, but they have often been identified with phenotypic methods, which may have resulted in misclassification. The aims of this paper were to assess the amount of misclassification of a phenotypic test for identifying CNS species from goat milk compared with transfer RNA intergenic spacer PCR (tDNA-PCR) followed by capillary electrophoresis, and to apply the tDNA-PCR technique on different capillary electrophoresis equipment. Milk samples were collected from 416 does in 5 Californian dairy goat herds on 3 occasions during lactation. In total, 219 CNS isolates were identified at the species level with tDNA-PCR and subjected to the API 20 Staph identification test kit (API Staph; bioMérieux, Durham, NC). If the same species was isolated multiple times from the same udder gland, only the first isolate was used for further analyses, resulting in 115 unique CNS isolates. According to the tDNA-PCR test, the most prevalent CNS species were Staphylococcus epidermidis, Staphylococcus caprae, and Staphylococcus simulans. Typeability with API staph was low (72%). Although the API Staph test was capable of identifying the majority of Staph. epidermidis and Staph. caprae isolates, sensitivity for identification of Staph. simulans was low. The true positive fraction was high for the 3 most prevalent species. It was concluded that the overall performance of API Staph in differentiating CNS species from goat milk was moderate to low, mainly because of the low typeability, and that genotypic methods such as tDNA-PCR are preferred. Copyright © 2012 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

[Antimicrobial sensitivity of the environmental microbiota in the intensive care units of a peruvian hospital].

PubMed

Díaz-Tello, José; Rojas-Jaimes, Jesús; Ibarra-Trujillo, Jimmy; Tárraga-Gonzales, Delza

2017-01-01

The objective was to detect Gram-negative bacilli and Gram-positive cocci isolated from the environmental microbiota of the Intensive Care Unit (ICU) departments of Neonatology, Pediatrics, and Transplants (kidney, liver, and general) in a Lima hospital and determine their antimicrobial sensitivity. Eighty samples were obtained from inanimate surfaces using a wet swab. A total of 61 bacterial strains were identified, including Staphylococcus epidermis (46.0%), Alcaligenes sp. (21.3%), Pseudomonas aeruginosa (16.4%), Acinetobacter sp. (13.1%), Staphylococcus aureus (1.6%), and Staphylococcus haemolyticus (1.6%). Acinetobacter sp. and P. aeruginosa showed a heightened sensitivity to the antibiotics assessed, while Alcaligenes sp. and S. epidermidis presented the highest antimicrobial resistance. It is recommended that sustained asepsis and monitoring methods be used in ICUs.

[ABILITY OF STAPHYLOCOCCUS OF VARIOUS STRAINS TO CREATE BIOFILMS AND THEIR EFFECT ON HUMAN BODY CELLS].

PubMed

Kornienko, M A; Kopyltsov, V N; Shevlyagina, N V; Didenko, L V; Lyubasovskaya, L A; Priputnevich, T V; Ilina, E N

2016-01-01

The urgency of the staphylococcus research is due to its ability to cause severe infections: softtissue infections, endocarditis, sepsis, toxic shock syndrome, and food poisoning. Coagulase-positive Staphylococcus aureus is the main infection agent of intrahospital infections. This agent has many factors of pathogenicity, which are well known. Among the coagulase-negative staphylococcus (CNS) strains, S. haemolyticus and S. epidermidis are clinically important, because they cause infections in patients with weak immune system. The mechanisms of the CNS pathogenicity are insufficiently understood. The goal of this work was to evaluate the potential pathogenicity of clinical strains of CNS from their capacity to create biofilms and the character of their interaction with human body cells by the example of the HT-29 cell culture. The research was carried out in laboratory strain S. aureus ATCC 29213 and clinical strains S. haemolyticus SH39, S. epidermidis SE36-1 isolated from the neonatal autopsy materials. The visual tests of biofilm formation by each strain and testing of the impact of the strains on the cell culture HT-29 was carried out in this work. The two species of CNS form biofilms at a higher rate than S. aureus. Upon incubation for 2 h of HT-29 cells with staphylococcus strains tested in this work, adhesion of bacteria on cell surface was observed. The adhesion was most pronounced in case of S. aureus ATCC 29213 and S. haemolyticus SH39. Upon 3 h of incubation with S. aureus ATCC 29213 and S. haemolyticus SH39, destruction of cell HT-29 monolayer was observed. The incubation for 24 h with the 3 strains tested in this work caused complete destruction of cell HT-29 monolayer. The maximal toxic effect on HT-29 cells was inherent in the strain S. haemolyticus SH39. The aggregate of the results obtained in this work indicates the presence of the pathogenicity factors in the strains S. haemolyticus SH39, which require additional research.

LEADER Program Results for 2009: an Activity and Spectrum Analysis of Linezolid Using 6,414 Clinical Isolates from 56 Medical Centers in the United States▿†

PubMed Central

Farrell, David J.; Mendes, Rodrigo E.; Ross, James E.; Sader, Helio S.; Jones, Ronald N.

2011-01-01

The LEADER Program monitors the in vitro activity of linezolid in sampled U.S. medical centers using reference broth microdilution methods with supporting molecular investigations in a central laboratory design. This report summarizes data obtained in 2009, the 6th consecutive year of this longitudinal study. A total of 6,414 isolates from 56 medical centers in all nine Census regions across the United States participated in 2009. For the six leading species/groups, the following linezolid MIC90 values were observed: Staphylococcus aureus, 2 μg/ml; coagulase-negative staphylococci (CoNS), 1 μg/ml; Enterococcus spp., 2 μg/ml; Streptococcus pneumoniae, 1 μg/ml; viridans group streptococci, 1 μg/ml; and beta-hemolytic streptococci, 1 μg/ml. Linezolid resistance was only 0.34% overall, with no evidence of significant increase in the LEADER Program since 2006. The predominant linezolid resistant mechanism found was a G2576T mutation in the 23S rRNA. L3/L4 riboprotein mutations were also found. The mobile multidrug-resistant cfr gene was found in four strains (two S. aureus strains and one strain each of S. epidermidis and S. capitis) from four different states, suggesting persistence but a lack of dissemination. Linezolid continues to exhibit excellent activity and spectrum, and this study documents the need for continued monitoring of emerging mechanisms of resistance over a wide geographic area. PMID:21670176

Aqueous Humor Penetration and Biological Activity of Moxifloxacin 0.5% Ophthalmic Solution Alone or with Dexamethasone 0.1.

PubMed

Gomes, Rachel L R; Viana, Rodrigo Galvão; Melo, Luiz Alberto S; Cruz, Alessandro Carvalho; Suenaga, Eunice Mayumi; Kenyon, Kenneth R; Campos, Mauro

2017-03-01

To compare aqueous humor concentrations of topically applied moxifloxacin 0.5% ophthalmic solution alone or in combination with dexamethasone 0.1% and to correlate these concentrations with the minimum inhibitory concentrations (MICs) for common endophthalmitis-causing organisms. Sixty-eight patients undergoing routine phacoemulsification with intraocular lens implantation received either moxifloxacin 0.5% alone or moxifloxacin 0.5% combined with dexamethasone. For both groups, 1 drop of the test solution was instilled 4 times daily 1 day preoperatively and 1 drop 1 h preoperatively. An aqueous humor sample obtained immediately before paracentesis was submitted to high-performance liquid chromatography-tandem mass spectrometry to determine the moxifloxacin concentration. The mean concentrations of moxifloxacin were 986.6 ng/mL in the moxifloxacin with dexamethasone group and 741.3 ng/mL in the moxifloxacin group (P = 0.13). Moxifloxacin concentrations of all samples exceeded the MICs for Staphylococcus epidermidis, S. aureus, and Streptococcus pneumoniae. All samples in the moxifloxacin with dexamethasone group and 94% in the moxifloxacin group achieved the MIC for Enterococcus species. For quinolone-resistant S. aureus, the MIC was achieved in 29% in the moxifloxacin with dexamethasone group and 9% in the moxifloxacin group (P = 0.06). Aqueous humor moxifloxacin concentrations were higher when topically administrated in combination with dexamethasone compared to the moxifloxacin alone. However, this difference was not statistically significant. Nevertheless, the MICs of the most common pathogens associated with endophthalmitis were exceeded in both study groups.

Comparison of a New Matrix-Assisted Laser Desorption/Ionization Time-of-Flight Mass Spectrometry Platform, ASTA MicroIDSys, With Bruker Biotyper for Species Identification.

PubMed

Lee, Yangsoon; Sung, Ji Yeon; Kim, Hyunsoo; Yong, Dongeun; Lee, Kyungwon

2017-11-01

Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry, with its accuracy and speed, is widely used for bacterial identification. The ASTA MicroIDSys system (ASTA, Korea) was recently developed for species identification. We compared its performance with that of Bruker Biotyper (Bruker Daltonics, Germany). Microbes were recovered from sputum, urine, and pus samples from patients admitted to a tertiary care hospital in Korea from January to April 2016. Matrix solution (α-cyano-4-hydroxycinnamic acid) was used, and the peptide profiles acquired from the Microflex LT (Bruker Daltonics) and Tinkerbell LT (ASTA) were analyzed by using their respective software. From 5,322 isolates, Bruker Biotyper identified 163 species; fifty species from 4,919 isolates were identified more than 10 times, including Klebsiella pneumoniae (n=571), Acinetobacter baumannii (n=436), Pseudomonas aeruginosa (n=358), Escherichia coli (n=372), Staphylococcus aureus (n=511), S. epidermidis (n=444), Enterococcus faecium (n=262), E. faecalis (n=220), and Candida albicans (n=248). Identical results, confidence scores (≥ 2.0 for Bruker Biotyper), and acceptable scores (≥140 for ASTA MicroIDSys) were obtained for 86.1% of isolates. Of 4,267 isolates, 99.2% showed acceptable scores in both systems. Results from the ASTA MicroIDSys showed good agreement with those from the Bruker Biotyper. The ASTA MicroIDSys could reliably identify clinically important microorganisms. © The Korean Society for Laboratory Medicine.

Antibacterial Activity of Silver Nanoparticle-Loaded Soft Contact Lens Materials: The Effect of Monomer Composition.

PubMed

Shayani Rad, Maryam; Khameneh, Bahman; Sabeti, Zahra; Mohajeri, Seyed Ahmad; Fazly Bazzaz, Bibi Sedigheh

2016-10-01

In the present work, the effect of monomer composition on silver nanoparticles' (SNPs) binding capacity of hydrogels was investigated and their antibacterial efficacy was evaluated. Three series of poly-hydroxyethyl methacrylate (HEMA) hydrogels were prepared using methacrylic acid (MAA), methacrylamide (MAAM), and 4-vinylpyridine (4VP) as co-monomers, and ethylene glycol dimethacrylate (EGDMA) as cross-linker. SNPs binding capacity of hydrogels was evaluated in different concentrations (2, 10, and 20 ppm). In vitro antibacterial activity of SNP-loaded hydrogels was studied against Pseudomonas aeruginosa (P. aeruginosa) isolated from patients' eyes. Then, inhibitory effect of hydrogels in biofilm formation was evaluated in the presence of Staphylococcus epidermidis (S. epidermidis) (DSMZ 3270). Our data indicated that poly(HEMA-co-MAA-co-EGDMA) had superior binding affinity for SNPs in comparison with other hydrogels. All SNP-loaded hydrogels demonstrated excellent antimicrobial effects at all times against P. aeruginosa and S. epidermidis after soaking in 10 and 20 ppm SNP suspensions. Scanning electron microscope (SEM) images revealed excellent inhibitory effect of SNPs against biofilm formation on the surface of the hydrogels. This study indicated the effect of monomer compositions in SNP loading capacity of poly(HEMA) hydrogels and antibacterial efficacy of SNP-loaded hydrogels against P. aeruginosa and S. epidermidis, but further in vivo evaluation is necessary.

Artificial biofilms establish the role of matrix interactions in staphylococcal biofilm assembly and disassembly.

PubMed

Stewart, Elizabeth J; Ganesan, Mahesh; Younger, John G; Solomon, Michael J

2015-08-14

We demonstrate that the microstructural and mechanical properties of bacterial biofilms can be created through colloidal self-assembly of cells and polymers, and thereby link the complex material properties of biofilms to well understood colloidal and polymeric behaviors. This finding is applied to soften and disassemble staphylococcal biofilms through pH changes. Bacterial biofilms are viscoelastic, structured communities of cells encapsulated in an extracellular polymeric substance (EPS) comprised of polysaccharides, proteins, and DNA. Although the identity and abundance of EPS macromolecules are known, how these matrix materials interact with themselves and bacterial cells to generate biofilm morphology and mechanics is not understood. Here, we find that the colloidal self-assembly of Staphylococcus epidermidis RP62A cells and polysaccharides into viscoelastic biofilms is driven by thermodynamic phase instability of EPS. pH conditions that induce phase instability of chitosan produce artificial S. epidermidis biofilms whose mechanics match natural S. epidermidis biofilms. Furthermore, pH-induced solubilization of the matrix triggers disassembly in both artificial and natural S. epidermidis biofilms. This pH-induced disassembly occurs in biofilms formed by five additional staphylococcal strains, including three clinical isolates. Our findings suggest that colloidal self-assembly of cells and matrix polymers produces biofilm viscoelasticity and that biofilm control strategies can exploit this mechanism.

Artificial biofilms establish the role of matrix interactions in staphylococcal biofilm assembly and disassembly

PubMed Central

Stewart, Elizabeth J.; Ganesan, Mahesh; Younger, John G.; Solomon, Michael J.

2015-01-01

We demonstrate that the microstructural and mechanical properties of bacterial biofilms can be created through colloidal self-assembly of cells and polymers, and thereby link the complex material properties of biofilms to well understood colloidal and polymeric behaviors. This finding is applied to soften and disassemble staphylococcal biofilms through pH changes. Bacterial biofilms are viscoelastic, structured communities of cells encapsulated in an extracellular polymeric substance (EPS) comprised of polysaccharides, proteins, and DNA. Although the identity and abundance of EPS macromolecules are known, how these matrix materials interact with themselves and bacterial cells to generate biofilm morphology and mechanics is not understood. Here, we find that the colloidal self-assembly of Staphylococcus epidermidis RP62A cells and polysaccharides into viscoelastic biofilms is driven by thermodynamic phase instability of EPS. pH conditions that induce phase instability of chitosan produce artificial S. epidermidis biofilms whose mechanics match natural S. epidermidis biofilms. Furthermore, pH-induced solubilization of the matrix triggers disassembly in both artificial and natural S. epidermidis biofilms. This pH-induced disassembly occurs in biofilms formed by five additional staphylococcal strains, including three clinical isolates. Our findings suggest that colloidal self-assembly of cells and matrix polymers produces biofilm viscoelasticity and that biofilm control strategies can exploit this mechanism. PMID:26272750

The Role of Ionic Interactions in the Adherence of the S. epidermidis Adhesin SdrF to Prosthetic Material

PubMed Central

Toba, Faustino A.; Visai, Livia; Trivedi, Sheetal; Lowy, Franklin D.

2012-01-01

Staphylococcus epidermidis infections are common complications of prosthetic device implantation. SdrF, a surface protein, appears to play a critical role in the initial colonization step by adhering to type I collagen and Dacron™. The role of ionic interactions in S. epidermidis adherence to prosthetic material was examined. SdrF was cloned and expressed in Lactococcus lactis. The effect of pH, cation concentration and detergents on adherence to different types of plastic surfaces was assessed by crystal violet staining and bacterial cell counting. SdrF, in contrast with controls and other S. epidermidis surface proteins, bound to hydrophobic materials such as polystyrene. Binding was an ionic interaction and was affected by surface charge of the plastic, pH and cation concentration. Adherence of the SdrF construct was increased to positively charged plastics and was reduced by increasing concentrations of Ca2+ and Na+. Binding was optimal at pH 7.4. Kinetic studies demonstrated that the SdrF B domain, as well as one of the B subdomains was sufficient to mediate binding. The SdrF construct also bound more avidly to Goretex™ than the lacotococcal control. SdrF is a multifunctional protein that contributes to prosthetic devices infections by ionic, as well as specific receptor-ligand interactions. PMID:23039791

Effects of transient high temperature treatment on the intestinal flora of the silkworm Bombyx mori.

PubMed

Sun, Zhenli; Kumar, Dhiraj; Cao, Guangli; Zhu, Liyuan; Liu, Bo; Zhu, Min; Liang, Zi; Kuang, Sulan; Chen, Fei; Feng, Yongjie; Hu, Xiaolong; Xue, Renyu; Gong, Chengliang

2017-06-13

The silkworm Bombyx mori is a poikilotherm and is therefore sensitive to various climatic conditions. The influence of temperature on the intestinal flora and the relationship between the intestinal flora and gene expression in the silkworm remain unknown. In the present study, changes of the intestinal flora at 48, 96 and 144 h following transient high temperature treatment (THTT) of 37 °C for 8 h were investigated. According to principal component analysis, the abundances of Enterococcus and Staphylococcus showed a negative correlation with other dominant genera. After THTT, the gene expression levels of spatzle-1 and dicer-2 were increased and decreased, respectively, which suggested that the Toll and RNAi pathways were activated and suppressed, respectively. The species-gene expression matrix confirmed that the spatzle-1 and dicer-2 gene expression levels were negatively and positively correlated, respectively, with the abundance of Enterococcus and Staphylococcus in the control. The abundance of Variovorax post-THTT was positively correlated with the spatzle-1 gene expression level, whereas the community richness of Enterococcus was negatively correlated with the spatzle-1 gene expression level and positively correlated with the dicer-2. The results of the present investigation provide new evidence for understanding the relationships among THTT, intestinal flora and host gene expression.

Confocal laser scanning microscopy analysis of S. epidermidis biofilms exposed to farnesol, vancomycin and rifampicin.

PubMed

Cerca, Nuno; Gomes, Fernanda; Pereira, Sofia; Teixeira, Pilar; Oliveira, Rosário

2012-05-16

Staphylococcus epidermidis is the major bacterial species found in biofilm-related infections on indwelling medical devices. Microbial biofilms are communities of bacteria adhered to a surface and surrounded by an extracellular polymeric matrix. Biofilms have been associated with increased antibiotic tolerance to the immune system. This increased resistance to conventional antibiotic therapy has lead to the search for new antimicrobial therapeutical agents. Farnesol, a quorum-sensing molecule in Candida albicans, has been described as impairing growth of several different microorganisms and we have previously shown its potential as an adjuvant in antimicrobial therapy against S. epidermidis. However, its mechanism of action in S. epidermidis is not fully known. In this work we better elucidate the role of farnesol against S: epidermidis biofilms using confocal laser scanning microscopy (CLSM). 24 h biofilms were exposed to farnesol, vancomycin or rifampicin and were analysed by CLSM, after stained with a Live/Dead stain, a known indicator of cell viability, related with cell membrane integrity. Biofilms were also disrupted by sonication and viable and cultivable cells were quantified by colony forming units (CFU) plating. Farnesol showed a similar effect as vancomycin, both causing little reduction of cell viability but at the same time inducing significant changes in the biofilm structure. On the other hand, rifampicin showed a distinct action in S. epidermidis biofilms, by killing a significant proportion of biofilm bacteria. While farnesol is not very efficient at killing biofilm bacteria, it damages cell membrane, as determined by the live/dead staining, in a similar way as vancomycin. Furthermore, farnesol might induce biofilm detachment, as determined by the reduced biofilm biomass, which can partially explain the previous findings regarding its role as a possible chemotherapy adjuvant.

Association of Enterococcus spp. with Severe Combat Extremity Injury, Intensive Care, and Polymicrobial Wound Infection.

PubMed

Heitkamp, Rae A; Li, Ping; Mende, Katrin; Demons, Samandra T; Tribble, David R; Tyner, Stuart D

2018-01-01

Combat-related extremity wound infections can complicate the recovery of injured military personnel. The Enterococcus genus contains both commensal and pathogenic bacteria found in many combat wounds. We describe the patient population susceptible to Enterococcus infection, the characteristics of Enterococcus spp. isolated from combat-related wounds, and the microbiological profile of Enterococcus-positive wounds. Patient and culture data were obtained from the Trauma Infectious Disease Outcomes Study. Subjects were divided into a case group with enterococcal extremity wound infections and a comparator group with wound infections caused by other micro-organisms. Case and comparator subjects had similar patterns of injury and infection. Case subjects had higher Injury Severity Scores (33 vs. 30; p < 0.001), longer hospitalization at U.S. facilities (55 vs. 40 days; p = 0.004), and required more large-volume blood transfusions (>20 units) within 24 h post-injury (53% vs. 30%; p < 0.001). Approximately 60% of case subjects had three or more infections, and 91% had one or more polymicrobial infections, compared with 43% and 50%, respectively, in the comparator group. The thigh was the most common site of Enterococcus spp. isolation, contributing 50% of isolates. Enterococcus faecium was the predominant species isolated from case-group infections overall (66%), as well as in polymicrobial infections (74%). Frequent co-colonizing microbes in polymicrobial wound infections with Enterococcus were other ESKAPE pathogens (64%) (Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae [and Escherichia coli], Acinetobacter baumannii, Pseudomonas aeruginosa, and Enterobacter spp.) and fungi (35%). The specific pathogenicity of Enterococcus relative to other pathogens in polymicrobial wounds is unknown. Identifying strain-specific outcomes and investigating the interactions of Enterococcus strains with other wound pathogens could provide additional tools and strategies for infection mitigation in combat-related wounds.

Synthesis, antiproliferative and antibacterial activity of new amides of salinomycin.

PubMed

Antoszczak, Michał; Maj, Ewa; Stefańska, Joanna; Wietrzyk, Joanna; Janczak, Jan; Brzezinski, Bogumil; Huczyński, Adam

2014-04-01

A series of 11 novel amides of salinomycin were synthesized for the first time. All the obtained compounds were found to show potent antiproliferative activity against human cancer cell lines including the drug-resistant cancer cells. Four new salinomycin derivatives revealed good antibacterial activity against clinical isolates of methicillin-resistant Staphylococcus epidermidis (MRSE). Copyright © 2014 Elsevier Ltd. All rights reserved.

Control of biofilm formation by poly-ethylene-co-vinyl acetate films incorporating nisin.

PubMed

Nostro, Antonia; Scaffaro, Roberto; Ginestra, Giovanna; D'Arrigo, Manuela; Botta, Luigi; Marino, Andreana; Bisignano, Giuseppe

2010-06-01

The aim of this study was to evaluate the effect of poly-ethylene-co-vinyl acetate (EVA) films incorporating different concentrations (0.1%, 0.5% and 1%) of nisin on the biofilm-forming ability of Listeria monocytogenes ATCC 7644, Staphylococcus aureus 815 and Staphylococcus epidermidis ATCC 35984. Nisin was incorporated into two grades of EVA (EVA14 and EVA28) in the melt during a common film-blowing operation. The efficacy of EVA/nisin films was evaluated by biofilm biomass measurements and Live/Dead staining in combination with fluorescence microscopy. In order to evaluate whether the nisin incorporation could modify the film surface properties, contact angle measurements and scanning electron microscopy were performed. The results revealed the efficacy of EVA14/nisin films in reducing biofilm formation on their surfaces with more evident effect for S. epidermidis than L. monocytogenes and S. aureus strains. In contrast, EVA28/nisin films showed unsatisfactory activity. Fluorescence microscopy confirmed poor biofilm formation on EVA14/nisin films, also characterised by the presence of dead cells. The data presented in this study offer new potential applications for developing strategies aimed to improve the effect of antimicrobial agents.

Inhibition of various gram-positive and gram- negative bacteria growth on selenium nanoparticle coated paper towels

PubMed Central

Wang, Qi; Larese-Casanova, Philip; Webster, Thomas J

2015-01-01

There are wide spread bacterial contamination issues on various paper products, such as paper towels hanging in sink splash zones or those used to clean surfaces, filter papers used in water and air purifying systems, and wrappings used in the food industry; such contamination may lead to the potential spread of bacteria and consequent severe health concerns. In this study, selenium nanoparticles were coated on normal paper towel surfaces through a quick precipitation method, introducing antibacterial properties to the paper towels in a healthy way. Their effectiveness at preventing biofilm formation was tested in bacterial assays involving Staphylococcus aureus, Pseudomonas aeruginosa, Escherichia coli, and Staphylococcus epidermidis. The results showed significant and continuous bacteria inhibition with about a 90% reduction from 24 to 72 hours for gram-positive bacteria including S. aureus and S. epidermidis. The selenium coated paper towels also showed significant inhibition of gram-negative bacteria like P. aeruginosa and E. coli growth at about 57% and 84%, respectively, after 72 hours of treatment. Therefore, this study established a promising selenium-based antibacterial strategy to prevent bacterial growth on paper products, which may lead to the avoidance of bacteria spreading and consequent severe health concerns. PMID:25926733

Antibacterial compounds from Salvia adenophora Fernald (Lamiaceae).

PubMed

Bisio, Angela; Schito, Anna Maria; Ebrahimi, Samad Nejad; Hamburger, Matthias; Mele, Giacomo; Piatti, Gabriella; Romussi, Giovanni; Dal Piaz, Fabrizio; De Tommasi, Nunziatina

2015-02-01

From the aerial parts of Salvia adenophora Fernald four derivatives of 12-oxo-phytodienoic acid (1-4) together with five clerodane diterpenoids (5, 6, 8-10), and one known diterpene (7) have been isolated. Compounds 1-6 and 8-10 are described for the first time. The structures were established by extensive 1D, 2D NMR and HRESI-TOFMS spectroscopic methods. Finally, the absolute configuration has been established by comparing of experimental and quantum chemical calculation of ECD spectra. Despite a total lack of antimicrobial activity of the plant extract, hinting to the existence of antagonistic interactions in the crude material, three oxylipins (2-4) displayed a promising inhibition on Gram-positive multidrug-resistant clinical strains including Staphylococcus aureus, Streptococcus agalactiae and, particularly, Staphylococcus epidermidis, while the compounds 9 and 10 revealed a specific and strain-dependent activity against S. epidermidis. Interestingly, the inhibition provided by these compounds was independent of the resistance patterns of these pathogens to classic antibiotics. No action was reported on Gram-negative strains nor on Candida albicans. These results confirm that clerodanes and, particularly, prostaglandin-like compounds can be considered as interesting antimicrobial agents deserving further study. Copyright © 2014 Elsevier Ltd. All rights reserved.

Inhibition of various gram-positive and gram-negative bacteria growth on selenium nanoparticle coated paper towels.

PubMed

Wang, Qi; Larese-Casanova, Philip; Webster, Thomas J

2015-01-01

There are wide spread bacterial contamination issues on various paper products, such as paper towels hanging in sink splash zones or those used to clean surfaces, filter papers used in water and air purifying systems, and wrappings used in the food industry; such contamination may lead to the potential spread of bacteria and consequent severe health concerns. In this study, selenium nanoparticles were coated on normal paper towel surfaces through a quick precipitation method, introducing antibacterial properties to the paper towels in a healthy way. Their effectiveness at preventing biofilm formation was tested in bacterial assays involving Staphylococcus aureus, Pseudomonas aeruginosa, Escherichia coli, and Staphylococcus epidermidis. The results showed significant and continuous bacteria inhibition with about a 90% reduction from 24 to 72 hours for gram-positive bacteria including S. aureus and S. epidermidis. The selenium coated paper towels also showed significant inhibition of gram-negative bacteria like P. aeruginosa and E. coli growth at about 57% and 84%, respectively, after 72 hours of treatment. Therefore, this study established a promising selenium-based antibacterial strategy to prevent bacterial growth on paper products, which may lead to the avoidance of bacteria spreading and consequent severe health concerns.

Bacteremia following dental implant surgery: preliminary results.

PubMed

Bölükbaşı, Nilüfer; Özdemir, Tayfun; Öksüz, Lütfiye; Gürler, Nezahat

2012-01-01

The aims of this study were to investigate the incidence of bacteremia, bacteriology and antibiotic susceptibility against to causative bacteria associated with dental implant installation. 30 generally healthy patients were enrolled in this study. Blood samples were collected at baseline and at 30 minutes after dental implant installation and 24 hours after dental implant surgery. Blood samples were cultured in a BACTEC system. The isolated bacteria were identified using conventional methods. Antimicrobial sensitivity tests were performed by disc diffusion. No bacteria were isolated at the baseline and 24 hours after surgery, whereas the prevalence of bacteremia at 30 minutes after dental implant installation was 23%. The isolated bacteria species were Staphylococcus epidermidis, Eubacterium spp., Corynebacterium spp. and Streptococcus viridans. The Staphylococcus epidermidis, which was isolated in three patients, was found to be resistant to penicillin which is first choice of many clinicians. Our findings suggest that installation of dental implants can produce bacteremia. Within the limitations of this study, it can be speculated that the resistance of antibiotics may compromise the routine prophylaxis against infective endocarditis. Therefore use of blood cultures and antibiograms may be suggested in risky patients. The outcome of the present study should be verified using a larger patient group with varying conditions.

Accumulation of multiple mutations in linezolid-resistant Staphylococcus epidermidis causing bloodstream infections; in silico analysis of L3 amino acid substitutions that might confer high-level linezolid resistance.

PubMed

Ikonomidis, Alexandros; Grapsa, Anastasia; Pavlioglou, Charikleia; Demiri, Antonia; Batarli, Alexandra; Panopoulou, Maria

2016-12-01

Fifty-six Staphylococcus epidermidis clinical isolates, showing high-level linezolid resistance and causing bacteremia in critically ill patients, were studied. All isolates belonged to ST22 clone and carried the T2504A and C2534T mutations in gene coding for 23SrRNA as well as the C189A, G208A, C209T and G384C missense mutations in L3 protein which resulted in Asp159Tyr, Gly152Asp and Leu94Val substitutions. Other silent mutations were also detected in genes coding for ribosomal proteins L3 and L22. In silico analysis of missense mutations showed that although L3 protein retained the sequence of secondary motifs, the tertiary structure was influenced. The observed alteration in L3 protein folding provides an indication on the putative role of L3-coding gene mutations in high-level linezolid resistance. Furthermore, linezolid pressure in health care settings where linezolid consumption is of high rates might lead to the selection of resistant mutants possessing L3 mutations that might confer high-level linezolid resistance.

Microbicidal activity of octenidine hydrochloride, a new alkanediylbis[pyridine] germicidal agent.

PubMed Central

Sedlock, D M; Bailey, D M

1985-01-01

The potential of octenidine hydrochloride (WIN 41464-2) as a topical microbicide was measured both by in vitro death kinetics and reductions in numbers of bacteria on the skin of cynomolgus monkeys. Semilogarithmic survival curves were plotted to measure the microbicidal activity of various concentrations of octenidine against Staphylococcus aureus. The microbicidal activity of octenidine was also determined for Staphylococcus epidermidis, Proteus mirabilis, Streptococcus pyogenes, Klebsiella pneumoniae, Escherichia coli, Pseudomonas aeruginosa, Serratia marcescens, and Candida albicans. Death rates for the same microbial strains were compared with those obtained by using chlorhexidine gluconate. Octenidine concentrations of less than 1.5 microM (0.94 microgram/ml) caused a greater than 99% reduction of each microbial population within 15 min. Staphylococcus epidermidis was the most susceptible of the test organisms, and E. coli and C. albicans were the least susceptible. Octenidine was more active than chlorhexidine against each test strain. Skin-degerming activities of aqueous and formulated octenidine and formulated chlorhexidine were compared in single and multiple applications of these agents to the hand and foot surfaces of monkeys by using a glove-juice extraction procedure to measure the skin microflora. Aqueous octenidine, at a concentration of 0.2 to 1.6% reduced resident microflora populations from 90 to 99.98%, depending on the concentration and number of applications. Octenidine formulated at 2% in a surfactant-based vehicle exhibited significantly better skin-degerming activity than did either a nonmedicated vehicle or the Hibiclens brand of 4% chlorhexidine gluconate. PMID:3909955

[Nationwide sensitivity surveillance of ciprofloxacin and various parenteral antibiotics against bacteria isolated from patients with severe infections--the first Ciproxan IV special investigation in 2001].

PubMed

Yamaguchi, Keizo; Ishii, Yoshikazu; Iinuma, Yoshitsugu; Yamanaka, Kiyoharu; Ichiyama, Satoshi; Watanabe, Naoki; Uehara, Nobuyuki; Kaku, Mitsuo; Kurokawa, Yukinori; Hayashi, Mutsumu; Hirakata, Yoichi

2003-12-01

The parenteral injection of ciprofloxacin (CPFX), a fluoroquinolone antimicrobial drug, was approved in September 2000 and a re-examination period of 6 years was set at that time. As a special investigation to apply for re-examination of this drug, it has been planned to conduct 3 nationwide surveillances during the re-examination period by collecting clinically isolated bacteria from patients with severe infections, to whom the drug was mainly indicated, and examining drug susceptibilities of the bacteria to various parenteral antimicrobial drugs including CPFX. This time, we determined the minimum inhibitory concentrations (MICs) of various parenteral antimicrobial drugs including CPFX against 1,220 strains isolated from patients with severe infections by the micro-liquid dilution method and compared susceptibilities of various clinically isolated bacteria to CPFX with those to other antimicrobial drugs. Gram-positive bacteria were less susceptible to CPFX than to carbapenems except 2 bacterial species, Enterococcus faecium and Enterococcus avium but susceptibilities of methicillin-susceptible Staphylococcus aureus (MSSA), Staphylococcus epidermidis and Enterococcus faecalis to CPFX were comparable to those to cefozopran. Susceptibility of Streptococcus pneumoniae to CPFX did not differ among ampicillin (ABPC)-susceptible Streptococcus pneumoniae (MIC of ABPC: < 0.25 microgram/ml), ABPC-intermediate S. pneumoniae (MIC of ABPC: 0.25-2 micrograms/ml) and ABPC-resistant S. pneumoniae (MIC of ABPC: > or = 4 micrograms/ml) MIC90 of CPFX: 1 microgram/ml) and a decrease in the antimicrobial activity seen among cephem and carbapenem antimicrobial drugs against penicillin-intermediate strains was not noted with CPFX. Gram-negative bacteria were susceptible to CPFX similarly to carbapenems and the MIC90 values of CPFX were in the range from < or = 0.063 to 2 micrograms/ml against strains except Stenotrophomonas maltophilia and Burkholderia cepacia. Pseudomonas aeruginosa was most susceptible to CPFX among the antibacterial drugs examined and the MIC90 was 2 micrograms/ml. CPFX also showed the lowest MIC90 value (0.5 microgram/ml) against beta-lactam-resistant P. aeruginosa among the drugs examined. When extended-spectrum beta-lactamase (ESBL) production and class B beta-lactamase production were examined in 439 strains of Enterobacteriaceae and 168 strains of glucose non-fermentative bacteria out of the Gram-negative bacteria collected this time, 3 strains (0.49%) producing ESBL and 7 strains (1.15%) producing class B beta-lactamase were found. The MIC range of CPFX to these 10 strains was between < or = 0.063 to 8 micrograms/ml and 5 strains among those showed susceptibilities (MIC of CPFX: 1 microgram/ml) based on the NCCLS breakpoint. CPFX also showed a satisfactory result concerning susceptibilities of major causal bacteria based on the report of the committee of Japan Society of Chemotherapy on the standard method for determination of susceptibility to antimicrobial agents, the breakpoint of pneumonia. Furthermore, susceptibilities of various bacteria isolated clinically from patients with severe infections this time did not differ much from the result of the nationwide surveillance which we conducted in 1997. Thus, it was concluded that the antimicrobial activity of CPFX was maintained in the post-marketing surveillance for its parenteral preparation.

Washing-resistant surfactant coated surface is able to inhibit pathogenic bacteria adhesion

NASA Astrophysics Data System (ADS)

Treter, Janine; Bonatto, Fernando; Krug, Cristiano; Soares, Gabriel Vieira; Baumvol, Israel Jacob Rabin; Macedo, Alexandre José

2014-06-01

Surface-active substances, which are able to organize themselves spontaneously on surfaces, triggering changes in the nature of the solid-liquid interface, are likely to influence microorganism adhesion and biofilm formation. Therefore, this study aimed to evaluate chemical non-ionic surfactants activity against pathogenic microbial biofilms and to cover biomaterial surfaces in order to obtain an anti-infective surface. After testing 11 different surfactants, Pluronic F127 was selected for further studies due to its non-biocidal properties and capability to inhibit up to 90% of biofilm formation of Gram-positive pathogen and its clinical isolates. The coating technique using direct impregnation on the surface showed important antibiofilm formation characteristics, even after extensive washes. Surface roughness and bacterial surface polarity does not influence the adhesion of Staphylococcus epidermidis, however, the material coated surface became extremely hydrophilic. The phenotype of S. epidermidis does not seem to have been affected by the contact with surfactant, reinforcing the evidence that a physical phenomenon is responsible for the activity. This paper presents a simple method of surface coating employing a synthetic surfactant to prevent S. epidermidis biofilm formation.

[Influence of staphylococcin T on Enterococcus sp. growth].

PubMed

Białucha, Agata; Kozuszko, Sylwia; Gospodarek, Eugenia; Bugalski, Roman Marian; Gierlotka, Krzysztof

2007-01-01

Bacteriocins are ribosomally synthesised, extracellular bacterial products. Generally, spectrum of inhibition is limited to the same or closely related species to bacteriocin producer. Staphylococcin T is produced by Staphylococcus cohnii strain. The present study concerns influence of StT to 267 Enterococcus sp. strains growth isolated between 2003 and 2006 in Department of Microbiology University Hospital of dr. A. Jurasz in Bydgoszcz. S. cohnii T antagonistic ability evaluated towards bacteries on Mueller-Hinton Agar (bio Mérieux) in aerobic conditions. After 24 and 48 hours tested enterococci suspensions were plated perpendiculary. Susceptibility to antibiotics was assessed by disc diffusion method according to the guideless of Clinical and Laboratory Standards Institute and National Reference Centre for Antimicrobial Susceptibility. Among Enterococcus sp. strains tested 7.1% were sensitive to StT. The highest percentage of sensitive enterococci isolated from wound swabs, urine, blood and pus. Enterococcus faecium strains dominated (63.2%) among enterococci sensitive to StT. Moderate inhibition degree on S. cohnii T bacteriocin action was observed in majority sensitive enterococci strains. Enterococcus sp. sensitive to StT strains were frequently multidrug resistant (68.4%). According to the study results and increasing resistance to antibiotics, StT could be an alternative agent used to treat infections caused by Enterococcus sp.

[In vitro comparison of antibacterial properties of antiseptics used in periodontology].

PubMed

Bezdenezhnykh, D S; Rusanova, E V; Nikitin, A A; Malychenko, N V

2012-01-01

Antibacterial properties of antiseptics most commonly used in periodontology were examined in vitro showing al agents containing chlorhexidine to be the most effective against gram-negative (E. coli), gram-positive (staphylococcus, streptococcus, enterococcus) germs as well as а C. аlbicans.

Isolation and identification of Staphylococcus sp. in powdered infant milk

NASA Astrophysics Data System (ADS)

Palilu, Prayolga Toban; Budiarso, Tri Yahya

2017-05-01

Staphylococcus sp. is one of the most dangerous bacteria that could cause food poisoning. It is a pathogenic bacterium which is able to produce enterotoxin in foods. Milk is an ideal growth medium for Staphylococcus sp., that may cause problem if it is to be consumed, especially by infant. It is the objective of this research to detect the presence of Staphylococcus sp. in powdered infant milk. As many as 14 samples obtained from market were used as samples for bacterial isolation. The isolation were done by employing enrichment step on BHI-broth, continued with Baird-Parker Agar which will produce a typical colony. It is then picked and grown on Mannitol Salt Agar, and gram staining, coagulase assay, and fermentation tests. The confirmation step was done by using API-Staph which gives the identification of Staphylococcus hemoliticus, Staphylococcus aureus and Staphylococcus epidermidis, with a percentage of identity ranging from 65.9-97.7%. Two isolates with the highest identification similarity values were then picked for molecular detection. A PCR primer pair targeting gene coding for enterotoxin A was used, and it gives positive result for the two isolates being tested. It is then concluded that the two isolates belong to Staphylococcus sp., and further research need to be done to correctly identify these isolates.

Effect of Ultraviolet Light Irradiation Combined with Riboflavin on Different Bacterial Pathogens from Ocular Surface Infection.

PubMed

Shen, Jing; Liang, Qingfeng; Su, Guanyu; Zhang, Yang; Wang, Zhiqun; Liang, Hong; Baudouin, Christophe; Labbé, Antoine

2017-01-01

In order to study Staphylococcus epidermis and Staphylococcus aureus in vitro viability after the exposure to ultraviolet (UV) light and riboflavin, twelve strains of Staphylococcus epidermis and twelve strains of Staphylococcus aureus were isolated from patients with bacterial keratitis. The growth situation of Staphylococcus epidermidis and Staphylococcus aureus under different experimental conditions was qualitatively observed. The number of colonies surviving bacteria was counted under different UV light power and different exposure time. The experiment showed that there was no inhibition effect on the growth of bacteria using riboflavin alone. In UV alone group and UV-riboflavin group, inhibition effect on the bacteria growth was found. The UV-riboflavin combination had better inhibition effect on bacteria than UV irradiation alone. The amount of bacteria in the UV-riboflavin group was decreased by 99.1%~99.5% and 54.8%~64.6% in the UV alone group, when the UV light power was 10.052 mW/cm 2 and the irradiation time was 30 min. Moreover, with the increase of the UV power or irradiation time, the survival rates of bacteria were rapidly reduced. Compared with Staphylococcus aureus , Staphylococcus epidermis was more easily to be killed under the action of UV light combined with riboflavin.

In Vitro Evaluation of Antimicrobial Activity of Alimentary Canal Extracts from the Red Palm Weevil, Rhynchophorus ferrugineus Olivier Larvae.

PubMed

Sewify, Gamal H; Hamada, Hanan M; Alhadrami, Hani A

2017-01-01

The invasive red palm weevil, Rhynchophorus ferrugineus Olivier (Coleoptera: Curculionidae), is considered one of the world's most devastating insect pests to palm trees. It was observed that larvae of this pest are able to inhibit microbial growth on the rearing media when they start feeding and this observation has led us to study the effect of red palm weevils on various microbial species. The antimicrobial effect of extracts from different parts of the alimentary canal on Gram positive bacteria ( Enterococcus faecalis and Staphylococcus aureus ), Gram negative bacteria ( Escherichia coli and Klebsiella spp.), Candida albicans, and Penicillium sp. was tested using the agar well diffusion method. All extracts inhibited the tested microbial species. Foregut extracts had the greatest zones of growth inhibition. Enterococcus faecalis , Staphylococcus aureus, and Penicillium sp. were significantly sensitive to the extracts and had the largest growth inhibition zones. It is concluded that the gut extracts contain potent antimicrobial activity and may provide a new source of antimicrobial peptides.

Multiplex Identification of Gram-Positive Bacteria and Resistance Determinants Directly from Positive Blood Culture Broths: Evaluation of an Automated Microarray-Based Nucleic Acid Test

PubMed Central

Buchan, Blake W.; Ginocchio, Christine C.; Manii, Ryhana; Cavagnolo, Robert; Pancholi, Preeti; Swyers, Lettie; Thomson, Richard B.; Anderson, Christopher; Kaul, Karen; Ledeboer, Nathan A.

2013-01-01

Background A multicenter study was conducted to evaluate the diagnostic accuracy (sensitivity and specificity) of the Verigene Gram-Positive Blood Culture Test (BC-GP) test to identify 12 Gram-positive bacterial gene targets and three genetic resistance determinants directly from positive blood culture broths containing Gram-positive bacteria. Methods and Findings 1,252 blood cultures containing Gram-positive bacteria were prospectively collected and tested at five clinical centers between April, 2011 and January, 2012. An additional 387 contrived blood cultures containing uncommon targets (e.g., Listeria spp., S. lugdunensis, vanB-positive Enterococci) were included to fully evaluate the performance of the BC-GP test. Sensitivity and specificity for the 12 specific genus or species targets identified by the BC-GP test ranged from 92.6%–100% and 95.4%–100%, respectively. Identification of the mecA gene in 599 cultures containing S. aureus or S. epidermidis was 98.6% sensitive and 94.3% specific compared to cefoxitin disk method. Identification of the vanA gene in 81 cultures containing Enterococcus faecium or E. faecalis was 100% sensitive and specific. Approximately 7.5% (87/1,157) of single-organism cultures contained Gram-positive bacteria not present on the BC-GP test panel. In 95 cultures containing multiple organisms the BC-GP test was in 71.6% (68/95) agreement with culture results. Retrospective analysis of 107 separate blood cultures demonstrated that identification of methicillin resistant S. aureus and vancomycin resistant Enterococcus spp. was completed an average of 41.8 to 42.4 h earlier using the BC-GP test compared to routine culture methods. The BC-GP test was unable to assign mecA to a specific organism in cultures containing more than one Staphylococcus isolate and does not identify common blood culture contaminants such as Micrococcus, Corynebacterium, and Bacillus. Conclusions The BC-GP test is a multiplex test capable of detecting most leading causes of Gram-positive bacterial blood stream infections as well as genetic markers of methicillin and vancomycin resistance directly from positive blood cultures. Please see later in the article for the Editors' Summary PMID:23843749

Consumer Exposure to Antimicrobial Resistant Bacteria From Food at Swiss Retail Level

PubMed Central

Jans, Christoph; Sarno, Eleonora; Collineau, Lucie; Meile, Leo; Stärk, Katharina D. C.; Stephan, Roger

2018-01-01

Background: Antimicrobial resistance (AMR) in bacteria is an increasing health concern. The spread of AMR bacteria (AMRB) between animals and humans via the food chain and the exchange of AMR genes requires holistic approaches for risk mitigation. The AMRB exposure of humans via food is currently only poorly understood leaving an important gap for intervention design. Method: This study aimed to assess AMRB prevalence in retail food and subsequent exposure of Swiss consumers in a systematic literature review of data published between 1996 and 2016 covering the Swiss agriculture sector and relevant imported food. Results: Data from 313 out of 9,473 collected studies were extracted yielding 122,438 food samples and 38,362 bacteria isolates of which 30,092 samples and 8,799 isolates were AMR positive. A median AMRB prevalence of >50% was observed for meat and seafood harboring Campylobacter, Enterococcus, Salmonella, Escherichia coli, Listeria, and Vibrio spp. and to a lesser prevalence for milk products harboring starter culture bacteria. Gram-negative AMRB featured predominantly AMR against aminoglycosides, cephalosporins, fluoroquinolones, penicillins, sulfonamides, and tetracyclines observed at AMR exposures scores of levels 1 (medium) and 2 (high) for Campylobacter, Salmonella, E. coli in meat as well as Vibrio and E. coli in seafood. Gram-positive AMRB featured AMR against glycoproteins, lincosamides, macrolides and nitrofurans for Staphylococcus and Enterococcus in meat sources, Staphylococcus in seafood as well as Enterococcus and technologically important bacteria (incl. starters) in fermented or processed dairy products. Knowledge gaps were identified for AMR prevalence in dairy, plant, fermented meat and novel food products and for the role of specific indicator bacteria (Staphylococcus, Enterococcus), starter culture bacteria and their mobile genetic elements in AMR gene transfer. Conclusion: Raw meat, milk, seafood, and certain fermented dairy products featured a medium to high potential of AMR exposure for Gram-negative and Gram-positive foodborne pathogens and indicator bacteria. Food at retail, additional food categories including fermented and novel foods as well as technologically important bacteria and AMR genetics are recommended to be better integrated into systematic One Health AMR surveillance and mitigation strategies to close observed knowledge gaps and enable a comprehensive AMR risk assessment for consumers. PMID:29559960

F-16 Microbially Influenced Corrosion (MIC) Characterization & Prevention Study

DTIC Science & Technology

2011-05-12

Staphylococcus epidermidis Fungal Consortium Aspergillus fumigatus Fusarium oxysporum Penicillium oxalicum Rhodoturula sp. Trichoderma sp. Control...Growth, or Soil and Dirt Accumulation • Fungal Consortium – Aspergillus sp (FI-19) Aureobasidium pullulans (FI-16) – Fusarium oxysporum (FI-6) Fusarium...species (common environmental isolates) – Minimal impact to health & safety • Fungal species promote MIC of Al2024-T3 alloy • Intergranular attack with

Effect of cefuroxime and moxifloxacin on Staphylococcus epidermidis adherence to intraocular lenses.

PubMed

Karadağ, Serhat; Ozkan, Berna; Karabaş, V Levent; Alintaş, Ozgül; Yumuk, Zeki; Cağlar, Yusuf

2009-12-01

To investigate and compare the effect of cefuroxime and moxifloxacin on adhesion of Staphylococcus epidermidis to intraocular lenses (IOLs). Experimental study. The 3-pieced hydrophobic acrylic lenses were contaminated with S. epidermidis (American Type Culture Collection 35983) solutions containing 108 colony-forming units. IOLs were inoculated into test tubes containing tryptic soy broth after being held in antibiotic solutions for 15 minutes. Sonication and vortex procedures were performed in order to remove all the remaining bacteria. From each tube 10 microL and 100 microL was taken and inoculated into sheep blood agar. The colonies were counted overnight. The statistical analyses were made using one-way ANOVA, Turkey Honestly Significant Differences test (HSD) and independent t tests, and a p value less than 0.05 was considered statistically significant. Overall, the mean numbers of colony-forming units on the lenses that were held in control, cefuroxime, moxifloxacin 0.5 mg/0.1 mL and moxifloxacin 0.1 mg/0.1 mL solutions were 1398 (SE 10.01 x 10(3)), 29.9 (SE 1.16 x 10(3)), 0.23 (SD 0.04 x 10(3)), and 0.41 (SD 0.05 x 10(3)), respectively. The evaluation using one-way ANOVA and Turkey HSD tests revealed significant statistical differences among the groups (p = 0.000). The evaluation using independent t tests revealed significant statistical differences between the 2 moxifloxacin groups (p < 0.05). Our results suggest that moxifloxacin and cefuroxime significantly inhibit bacterial adherence to IOLs. The effect of moxifloxacin on inhibition of bacterial adherence was significantly greater than that of cefuroxime. For this reason moxifloxacin might be considered as a better prophylactic agent.

Chemical Genetic Analysis and Functional Characterization of Staphylococcal Wall Teichoic Acid 2-Epimerases Reveals Unconventional Antibiotic Drug Targets.

PubMed

Mann, Paul A; Müller, Anna; Wolff, Kerstin A; Fischmann, Thierry; Wang, Hao; Reed, Patricia; Hou, Yan; Li, Wenjin; Müller, Christa E; Xiao, Jianying; Murgolo, Nicholas; Sher, Xinwei; Mayhood, Todd; Sheth, Payal R; Mirza, Asra; Labroli, Marc; Xiao, Li; McCoy, Mark; Gill, Charles J; Pinho, Mariana G; Schneider, Tanja; Roemer, Terry

2016-05-01

Here we describe a chemical biology strategy performed in Staphylococcus aureus and Staphylococcus epidermidis to identify MnaA, a 2-epimerase that we demonstrate interconverts UDP-GlcNAc and UDP-ManNAc to modulate substrate levels of TarO and TarA wall teichoic acid (WTA) biosynthesis enzymes. Genetic inactivation of mnaA results in complete loss of WTA and dramatic in vitro β-lactam hypersensitivity in methicillin-resistant S. aureus (MRSA) and S. epidermidis (MRSE). Likewise, the β-lactam antibiotic imipenem exhibits restored bactericidal activity against mnaA mutants in vitro and concomitant efficacy against 2-epimerase defective strains in a mouse thigh model of MRSA and MRSE infection. Interestingly, whereas MnaA serves as the sole 2-epimerase required for WTA biosynthesis in S. epidermidis, MnaA and Cap5P provide compensatory WTA functional roles in S. aureus. We also demonstrate that MnaA and other enzymes of WTA biosynthesis are required for biofilm formation in MRSA and MRSE. We further determine the 1.9Å crystal structure of S. aureus MnaA and identify critical residues for enzymatic dimerization, stability, and substrate binding. Finally, the natural product antibiotic tunicamycin is shown to physically bind MnaA and Cap5P and inhibit 2-epimerase activity, demonstrating that it inhibits a previously unanticipated step in WTA biosynthesis. In summary, MnaA serves as a new Staphylococcal antibiotic target with cognate inhibitors predicted to possess dual therapeutic benefit: as combination agents to restore β-lactam efficacy against MRSA and MRSE and as non-bioactive prophylactic agents to prevent Staphylococcal biofilm formation.

Polysaccharide intercellular adhesin in biofilm: structural and regulatory aspects

PubMed Central

Arciola, Carla Renata; Campoccia, Davide; Ravaioli, Stefano; Montanaro, Lucio

2015-01-01

Staphylococcus aureus and Staphylococcus epidermidis are the leading etiologic agents of implant-related infections. Biofilm formation is the main pathogenetic mechanism leading to the chronicity and irreducibility of infections. The extracellular polymeric substances of staphylococcal biofilms are the polysaccharide intercellular adhesin (PIA), extracellular-DNA, proteins, and amyloid fibrils. PIA is a poly-β(1-6)-N-acetylglucosamine (PNAG), partially deacetylated, positively charged, whose synthesis is mediated by the icaADBC locus. DNA sequences homologous to ica locus are present in many coagulase-negative staphylococcal species, among which S. lugdunensis, however, produces a biofilm prevalently consisting of proteins. The product of icaA is an N-acetylglucosaminyltransferase that synthetizes PIA oligomers from UDP-N-acetylglucosamine. The product of icaD gives optimal efficiency to IcaA. The product of icaC is involved in the externalization of the nascent polysaccharide. The product of icaB is an N-deacetylase responsible for the partial deacetylation of PIA. The expression of ica locus is affected by environmental conditions. In S. aureus and S. epidermidis ica-independent alternative mechanisms of biofilm production have been described. S. epidermidis and S. aureus undergo to a phase variation for the biofilm production that has been ascribed, in turn, to the transposition of an insertion sequence in the icaC gene or to the expansion/contraction of a tandem repeat naturally harbored within icaC. A role is played by the quorum sensing system, which negatively regulates biofilm formation, favoring the dispersal phase that disseminates bacteria to new infection sites. Interfering with the QS system is a much debated strategy to combat biofilm-related infections. In the search of vaccines against staphylococcal infections deacetylated PNAG retained on the surface of S. aureus favors opsonophagocytosis and is a potential candidate for immune-protection. PMID:25713785

Quantifying the pattern of microbial cell dispersion, density and clustering on surfaces of differing chemistries and topographies using multifractal analysis.

PubMed

Wickens, David; Lynch, Stephen; West, Glen; Kelly, Peter; Verran, Joanna; Whitehead, Kathryn A

2014-09-01

The effects of surface topography on bacterial distribution across a surface are of extreme importance when designing novel, hygienic or antimicrobial surface coatings. The majority of methods that are deployed to describe the pattern of cell dispersion, density and clustering across surfaces are currently qualitative. This paper presents a novel application of multifractal analysis to quantitatively measure these factors using medically relevant microorganisms (Staphylococcus aureus or Staphylococcus epidermidis). Surfaces (medical grade 316 stainless steel) and coatings (Ti-ZrN, Ti-ZrN/6.0%Ag, Ti-ZrN/15.6%Ag, TiZrN/24.7%Ag) were used in microbiological retention assays. Results demonstrated that S. aureus displayed a more heterogeneous cell dispersion (∆αAS<1) whilst the dispersion of S. epidermidis was more symmetric and homogeneous (∆αAS≥1). Further, although the surface topography and chemistry had an effect on cell dispersion, density and clustering, the type of bonding that occurred at the surface interface was also important. Both types of cells were influenced by both surface topographical and chemical effects; however, S. aureus was influenced marginally more by surface chemistry whilst S. epidermidis cells was influenced marginally more by surface topography. Thus, this effect was bacterially species specific. The results demonstrate that multifractal analysis is a method that can be used to quantitatively analyse the cell dispersion, density and clustering of retained microorganisms on surfaces. Using quantitative descriptors has the potential to aid the understanding the effect of surface properties on the production of hygienic and antimicrobial coatings. Copyright © 2014 Elsevier B.V. All rights reserved.

Chemical Genetic Analysis and Functional Characterization of Staphylococcal Wall Teichoic Acid 2-Epimerases Reveals Unconventional Antibiotic Drug Targets

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mann, Paul A.; Müller, Anna; Wolff, Kerstin A.

Here we describe a chemical biology strategy performed in Staphylococcus aureus and Staphylococcus epidermidis to identify MnaA, a 2-epimerase that we demonstrate interconverts UDP-GlcNAc and UDP-ManNAc to modulate substrate levels of TarO and TarA wall teichoic acid (WTA) biosynthesis enzymes. Genetic inactivation of mnaA results in complete loss of WTA and dramatic in vitro β-lactam hypersensitivity in methicillin-resistant S. aureus (MRSA) and S. epidermidis (MRSE). Likewise, the β-lactam antibiotic imipenem exhibits restored bactericidal activity against mnaA mutants in vitro and concomitant efficacy against 2-epimerase defective strains in a mouse thigh model of MRSA and MRSE infection. Interestingly, whereas MnaA servesmore » as the sole 2-epimerase required for WTA biosynthesis in S. epidermidis, MnaA and Cap5P provide compensatory WTA functional roles in S. aureus. We also demonstrate that MnaA and other enzymes of WTA biosynthesis are required for biofilm formation in MRSA and MRSE. We further determine the 1.9Å crystal structure of S. aureus MnaA and identify critical residues for enzymatic dimerization, stability, and substrate binding. Finally, the natural product antibiotic tunicamycin is shown to physically bind MnaA and Cap5P and inhibit 2-epimerase activity, demonstrating that it inhibits a previously unanticipated step in WTA biosynthesis. In summary, MnaA serves as a new Staphylococcal antibiotic target with cognate inhibitors predicted to possess dual therapeutic benefit: as combination agents to restore β-lactam efficacy against MRSA and MRSE and as non-bioactive prophylactic agents to prevent Staphylococcal biofilm formation.« less

Methicillin resistance of Staphylococcus species among health care and nonhealth care workers undergoing cataract surgery.

PubMed

Olson, Randall; Donnenfeld, Eric; Bucci, Frank A; Price, Francis W; Raizman, Michael; Solomon, Kerry; Devgan, Uday; Trattler, William; Dell, Steven; Wallace, R Bruce; Callegan, Michelle; Brown, Heather; McDonnell, Peter J; Conway, Taryn; Schiffman, Rhett M; Hollander, David A

2010-12-10

The purpose of this study is to characterize the bacterial flora of the ocular and periocular surface in cataract surgery patients and to determine the prevalence of methicillin resistance among staphylococcal isolates obtained from health care workers (HCWs) and non-HCWs. In this prospective, multicenter, case series study, eyelid and conjunctival cultures were obtained from the nonoperative eye of 399 consecutive cataract patients on the day of surgery prior to application of topical anesthetics, antibiotics, or antiseptics. Speciation and susceptibility testing were performed at the Dean A. McGee Eye Institute. Logistic regression was utilized to evaluate whether any factors were significant in predicting the presence of methicillin-resistant staphylococcal isolates. Staphylococcus epidermidis (62.9%), followed by S. aureus (14.0%), was the most frequently isolated organism. Methicillin-resistant S. epidermidis accounted for 47.1% (178/378) of S. epidermidis isolates, and methicillin-resistant S. aureus accounted for 29.5% (26/88) of S. aureus isolates. Methicillin-resistant staphylococcal isolates were found in 157 of 399 (39.3%) patients, the majority (89.2%) of whom were non-HCWs. The likelihood of being colonized with methicillin-resistant organisms increased with age (odds ratio [OR], 1.27; 95% confidence interval [CI]: 1.02-1.58; P = 0.04) but decreased with diabetes (OR, 0.51; 95% CI: 0.29-0.89; P = 0.02). Being a HCW (OR, 1.25; 95% CI: 0.61-2.58; P = 0.54) was not a risk factor for colonization with methicillin-resistant organisms. Patients without exposure to health care environments are as likely as HCWs to be colonized with methicillin-resistant organisms. Increasing methicillin resistance with age may partially explain the increased risk of endophthalmitis reported with older age.

Neither non-toxigenic Staphylococcus aureus nor commensal S. epidermidi activates NLRP3 inflammasomes in human conjunctival goblet cells

PubMed Central

Li, Dayu; Hodges, Robin R; Bispo, Paulo; Gilmore, Michael S; Gregory-Ksander, Meredith; Dartt, Darlene A

2017-01-01

Purpose The conjunctiva is a wet mucosal surface surrounding the cornea that is continuously exposed to pathogens. Nevertheless, persistent inflammation is not observed. We examined if the NOD-like receptor pyrin domain 3 (NLRP3) inflammasome functions as a sensor that distinguishes commensal and non-pathogenic bacteria from pathogenic bacteria in human conjunctival goblet cells. Methods Goblet cells were grown from human conjunctiva and co-cultured with commensal Staphylococcus epidermidis, isogenic non-toxigenic S. aureus ACL135 and as a control toxigenic S. aureus RN6390. Activation of the NLRP3 inflammasome was determined by measuring changes in NF-κB activity, expression of pro-interleukin (IL)-1β and NLRP3, activation of caspase-1 and secretion of mature IL-1β. Goblet cell mucin secretion was measured in parallel. Results While all three strains of bacteria were able to bind to goblet cells, neither commensal S. epidermidis nor isogenic non-toxigenic S. aureus ACL135 was able to stimulate an increase in (1) NF-κB activity, (2) pro-IL-1β and NLRP3 expression, (3) caspase-1 activation, (4) mature IL-1β and (5) mucin secretion. Toxigenic S. aureus, the positive control, increased these values: knockdown of NLRP3 with small interfering RNA (siRNA) completely abolished the toxigenic S. aureus-induced expression of pro-IL-1β and secretion of mature IL-1β. Conclusions We conclude that NLRP3 serves as a sensor capable of discriminating commensal and non-pathogenic bacteria from pathogenic bacteria in conjunctival goblet cells, and that activation of the NLRP3 inflammasome induced by pathogenic bacteria mediates secretion of both mature IL-1β and large secretory mucins from these cells. PMID:29354725

Methicillin resistance of Staphylococcus species among health care and nonhealth care workers undergoing cataract surgery

PubMed Central

Olson, Randall; Donnenfeld, Eric; Bucci, Frank A; Price, Francis W; Raizman, Michael; Solomon, Kerry; Devgan, Uday; Trattler, William; Dell, Steven; Wallace, R Bruce; Callegan, Michelle; Brown, Heather; McDonnell, Peter J; Conway, Taryn; Schiffman, Rhett M; Hollander, David A

2010-01-01

Purpose: The purpose of this study is to characterize the bacterial flora of the ocular and periocular surface in cataract surgery patients and to determine the prevalence of methicillin resistance among staphylococcal isolates obtained from health care workers (HCWs) and non-HCWs. Methods: In this prospective, multicenter, case series study, eyelid and conjunctival cultures were obtained from the nonoperative eye of 399 consecutive cataract patients on the day of surgery prior to application of topical anesthetics, antibiotics, or antiseptics. Speciation and susceptibility testing were performed at the Dean A. McGee Eye Institute. Logistic regression was utilized to evaluate whether any factors were significant in predicting the presence of methicillin-resistant staphylococcal isolates. Results: Staphylococcus epidermidis (62.9%), followed by S. aureus (14.0%), was the most frequently isolated organism. Methicillin-resistant S. epidermidis accounted for 47.1% (178/378) of S. epidermidis isolates, and methicillin-resistant S. aureus accounted for 29.5% (26/88) of S. aureus isolates. Methicillin-resistant staphylococcal isolates were found in 157 of 399 (39.3%) patients, the majority (89.2%) of whom were non-HCWs. The likelihood of being colonized with methicillin-resistant organisms increased with age (odds ratio [OR], 1.27; 95% confidence interval [CI]: 1.02–1.58; P = 0.04) but decreased with diabetes (OR, 0.51; 95% CI: 0.29–0.89; P = 0.02). Being a HCW (OR, 1.25; 95% CI: 0.61–2.58; P = 0.54) was not a risk factor for colonization with methicillin-resistant organisms. Conclusion: Patients without exposure to health care environments are as likely as HCWs to be colonized with methicillin-resistant organisms. Increasing methicillin resistance with age may partially explain the increased risk of endophthalmitis reported with older age. PMID:21191448

Augmented Expression of Polysaccharide Intercellular Adhesin in a Defined Staphylococcus epidermidis Mutant with the Small-Colony-Variant Phenotype▿

PubMed Central

Al Laham, Nahed; Rohde, Holger; Sander, Gunnar; Fischer, Andreas; Hussain, Muzaffar; Heilmann, Christine; Mack, Dietrich; Proctor, Richard; Peters, Georg; Becker, Karsten; von Eiff, Christof

2007-01-01

While coagulase-negative staphylococci (CoNS), with their ability to form a thick, multilayered biofilm on foreign bodies, have been identified as the major cause of implant-associated infections, no data are available about biofilm formation by staphylococcal small-colony variants (SCVs). In the past years, a number of device-associated infections due to staphylococcal SCVs were described, among them, several pacemaker infections due to SCVs of CoNS auxotrophic to hemin. To test the characteristics of SCVs of CoNS, in particular, to study the ability of SCVs to form a biofilm on foreign bodies, we generated a stable mutant in electron transport by interrupting one of the hemin biosynthetic genes, hemB, in Staphylococcus epidermidis. In fact, this mutant displayed a stable SCV phenotype with tiny colonies showing strong adhesion to the agar surface. When the incubation time was extended to 48 h or a higher inoculum concentration was used, the mutant produced biofilm amounts on polystyrene similar to those produced by the parent strain. When grown under planktonic conditions, the mutant formed markedly larger cell clusters than the parental strain which were completely disintegrated by the specific β-1,6-hexosaminidase dispersin B but were resistant to trypsin treatment. In a dot blot assay, the mutant expressed larger amounts of polysaccharide intercellular adhesin (PIA) than the parent strain. In conclusion, interrupting a hemin biosynthetic gene in S. epidermidis resulted in an SCV phenotype. Markedly larger cell clusters and the ability of the hemB mutant to form a biofilm are related to the augmented expression of PIA. PMID:17449620

Do Staphylococcus epidermidis Genetic Clusters Predict Isolation Sources?

PubMed Central

Tolo, Isaiah; Thomas, Jonathan C.; Fischer, Rebecca S. B.; Brown, Eric L.; Gray, Barry M.

2016-01-01

Staphylococcus epidermidis is a ubiquitous colonizer of human skin and a common cause of medical device-associated infections. The extent to which the population genetic structure of S. epidermidis distinguishes commensal from pathogenic isolates is unclear. Previously, Bayesian clustering of 437 multilocus sequence types (STs) in the international database revealed a population structure of six genetic clusters (GCs) that may reflect the species' ecology. Here, we first verified the presence of six GCs, including two (GC3 and GC5) with significant admixture, in an updated database of 578 STs. Next, a single nucleotide polymorphism (SNP) assay was developed that accurately assigned 545 (94%) of 578 STs to GCs. Finally, the hypothesis that GCs could distinguish isolation sources was tested by SNP typing and GC assignment of 154 isolates from hospital patients with bacteremia and those with blood culture contaminants and from nonhospital carriage. GC5 was isolated almost exclusively from hospital sources. GC1 and GC6 were isolated from all sources but were overrepresented in isolates from nonhospital and infection sources, respectively. GC2, GC3, and GC4 were relatively rare in this collection. No association was detected between fdh-positive isolates (GC2 and GC4) and nonhospital sources. Using a machine learning algorithm, GCs predicted hospital and nonhospital sources with 80% accuracy and predicted infection and contaminant sources with 45% accuracy, which was comparable to the results seen with a combination of five genetic markers (icaA, IS256, sesD [bhp], mecA, and arginine catabolic mobile element [ACME]). Thus, analysis of population structure with subgenomic data shows the distinction of hospital and nonhospital sources and the near-inseparability of sources within a hospital. PMID:27076664

No lower bacterial adhesion for ceramics compared to other biomaterials: An in vitro analysis.

PubMed

Slullitel, P A; Buttaro, M A; Greco, G; Oñativia, J I; Sánchez, M L; Mc Loughlin, S; García-Ávila, C; Comba, F; Zanotti, G; Piccaluga, F

2018-06-01

Although there is some clinical evidence of ceramic bearings being associated with a lower infection rate after total hip arthroplasty (THA), available data remains controversial since this surface is usually reserved for young, healthy patients. Therefore, we investigated the influence of five commonly used biomaterials on the adhesion potential of four biofilm-producing bacteria usually detected in infected THAs. Ceramic biomaterials exhibit less bacterial adherence than other biomaterials. In this in vitro research, we evaluated the ability of Staphylococcus aureus, Staphylococcus epidermidis ATCC 35984, Escherichia coli ATCC 25922 and Pseudomonas aeruginosa to adhere to the surface of a cobalt-chromium metal head, a fourth-generation ceramic head, a fourth-generation ceramic insert, a highly-crossed linked polyethylene insert and a titanium porous-coated acetabular component. After an initial washing step, bacterial separation from the surface of each specimen was done with a vortex agitator. The colony-forming units were counted to determine the number of viable adherent bacteria. We found no differences on global bacterial adhesion between the different surfaces (p=0.5). E. coli presented the least adherence potential among the analysed pathogens (p<0.001). The combination of E. coli and S. epidermidis generated an antagonist effect over the adherence potential of S. epidermidis individually (58±4% vs. 48±5%; p=0.007). The combination of P. aeruginosa and S. aureus presented a trend to an increased adherence of P. aeruginosa independently, suggesting an agonist effect (71% vs. 62%; p=0.07). Ceramic bearings appeared not to be related to a lower bacterial adhesion than other biomaterials. However, different adhesive potentials among bacteria may play a major role on infection's inception. IV, in vitro study. Copyright © 2018 Elsevier Masson SAS. All rights reserved.

Antimicrobial activity of Schinus lentiscifolius (Anacardiaceae).

PubMed

Gehrke, Ilaine T S; Neto, Alexandre T; Pedroso, Marcelo; Mostardeiro, Clarice P; Da Cruz, Ivana B M; Silva, Ubiratan F; Ilha, Vinicius; Dalcol, Ionara I; Morel, Ademir F

2013-07-09

Schinus lentiscifolius Marchand (syn. Schinus weinmannifolius Engl) is a plant native to Rio Grande do Sul (Southern Brazil) and has been used in Brazilian traditional medicine as antiseptic and antimicrobial for the treatment of many different health problems as well as to treat leucorrhea and to assist in ulcer and wound healing. Although it is a plant widely used by the population, there are no studies proving this popular use. The crude aqueous extract, the crude neutral methanol extract, fractions prepared from this extract (n-hexane, ethyl acetate, and n-butanol), pure compounds isolated from these fractions, and derivatives were investigated in vitro for antimicrobial activities against five Gram positive bacteria: Bacillus subtilis, Staphylococcus aureus, Staphylococcus epidermidis, Staphylococcus saprophyticus, Streptococcus pyogenes, three Gram negative bacteria: Escherichia coli, Pseudomonas aeruginosa, and Shigella sonnei, and four yeasts: Candida albicans, Candida tropicalis, Cryptococcus neoformans, and Saccharomyces cerevisiae. The isolated compound moronic acid, which is the most active, was tested against a range of other bacteria such as two Gram positive bacteria, namely, Bacillus cereus, Enterococcus spp, and six Gram negative bacteria, namely, Burkholderia cepacia, Providencia stuartii, Morganella morganii, Enterobacter cloacae, Enterobacter aerogenes, and Proteus mirabilis. The leaf aqueous extract (decoction) of Schinus lentiscifolius showed a broad spectrum of antibacterial activity, ranging from 125 to 250 μg/ml (MIC) against the tested bacteria and fungi. The n-hexane extract, despite being very little active against bacteria, showed an excellent antifungal activity, especially against Candida albicans (MIC=25 μg/ml), Candida tropicalis (MIC=15.5 μg/ml), and Cryptococcus neoformans, (MIC=15.5 μg/ml). From the acetate fraction (the most active against bacteria), compounds 1-6 were isolated: nonadecanol (1), moronic acid (2), gallic acid methyl ester (3), gallic acid (4), quercetin (5) and quercitrin (6). The minimal inhibitory concentration (MIC) of moronic acid between 1.5 and 3 μg/ml against most of the tested bacteria shows that it is one of the metabolites responsible for the antibacterial activity of Schinus lentiscifolius. The antimicrobial activity and some constituents of Schinus lentiscifolius are reported for the first time. The results of the present study provide scientific basis for the popular use of Schinus lentiscifolius for a number of different health problems. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

In vitro antimicrobial effects of a novel Pentaherbs concoction for atopic dermatitis.

PubMed

Hon, Kam Lun; Ip, Margaret; Wong, Chun Kwok; Chan, Ben Chung Lap; Leung, Ping Chung; Leung, Ting Fan

2018-05-01

In a series of bench and clinical trials, our group has determined the immunologic effects and clinical efficacy of a concoction of five herbal ingredients (PentaHerbs Formula, PHF) in treating children with atopic eczema (AE). This study investigates the antimicrobial effects that may be induced with PHF treatment. We investigated the effects of PHF on the minimal inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of Staphylococcus aureus and various bacteria that are commonly present on the skin of patients with AE. Staphylococcus aureus ATCC 25923, Methicllin resistant Staphylococcus aureus (MRSA) ATCC BAA-43, Enterococcus faecalis ATCC 29212, Pseudomonas aeruginosa ATCC 27853, Escherichia coli ATCC 25922, Enterobacter cloacae ATCC 13047, Proteus vulgaris ATCC 6380, and Acinetobacter baumannii ATCC 19606 were tested. PHF was more effective against Staphylococcus aureus ATCC 25923 and Methicllin resistant Staphylococcus aureus (MRSA) ATCC BAA-43. MIC and MBC were 1 and 25 mg/mL, respectively. PHF was more effective against Staphylococcus aureus ATCC 25923 and Methicllin resistant Staphylococcus aureus (MRSA) ATCC BAA-43t. PHF may be developed into a Staphylococcus aureus targeting topical application.

[Vancomycin-resistant Staphylococcus aureus].

PubMed

Rodríguez, Carlos Andrés; Vesga, Omar

2005-12-01

The evolution and molecular mechanisms of vancomycin resistance in Staphylococcus aureus were reviewed. Case reports and research studies on biochemestry, electron microscopy and molecular biology of Staphylococcus aureus were selected from Medline database and summarized in the following review. After almost 40 years of successful treatment of S. aureus with vancomycin, several cases of clinical failures have been reported (since 1997). S. aureus strains have appeared with intermediate susceptibility (MIC 8-16 microg/ml), as well as strains with heterogeneous resistance (global MIC < or =4 microg/ml), but with subpopulations of intermediate susceptibility. In these cases, resistance is mediated by cell wall thickening with reduced cross linking. This traps the antibiotic before it reaches its major target, the murein monomers in the cell membrane. In 2002, a total vancomycin resistant strain (MIC > or =32 microg/ml) was reported with vanA genes from Enterococcus spp. These genes induce the change of D-Ala-D-Ala terminus for D-Ala-D-lactate in the cell wall precursors, leading to loss of affinity for glycopeptides. Vancomycin resistance in S. aureus has appeared; it is mediated by cell wall modifications that trap the antibiotic before it reaches its action site. In strains with total resistance, Enterococcus spp. genes have been acquired that lead to modification of the glycopeptide target.

Molecular and Phenotypic Characterization of Staphylococcus epidermidis Isolates from Healthy Conjunctiva and a Comparative Analysis with Isolates from Ocular Infection

PubMed Central

Flores-Páez, Luis A.; Zenteno, Juan C.; Alcántar-Curiel, María D.; Vargas-Mendoza, Carlos F.; Rodríguez-Martínez, Sandra; Cancino-Diaz, Mario E.; Jan-Roblero, Janet; Cancino-Diaz, Juan C.

2015-01-01

Staphylococcus epidermidis is a common commensal of healthy conjunctiva and it can cause endophthalmitis, however its presence in conjunctivitis, keratitis and blepharitis is unknown. Molecular genotyping of S. epidermidis from healthy conjunctiva could provide information about the origin of the strains that infect the eye. In this paper two collections of S. epidermidis were used: one from ocular infection (n = 62), and another from healthy conjunctiva (n = 45). All isolates were genotyped by pulsed field gel electrophoresis (PFGE), multilocus sequence typing (MLST), staphylococcal cassette chromosome mec (SCCmec), detection of the genes icaA, icaD, IS256 and polymorphism type of agr locus. The phenotypic data included biofilm production and antibiotic resistance. The results displayed 61 PFGE types from 107 isolates and they were highly discriminatory. MLST analysis generated a total of 25 STs, of which 11 STs were distributed among the ocular infection isolates and lineage ST2 was the most frequent (48.4%), while 14 STs were present in the healthy conjunctiva isolates and lineage ST5 was the most abundant (24.4%). By means of a principal coordinates analysis (PCoA) and a discriminant analysis (DA) it was found that ocular infection isolates had as discriminant markers agr III or agr II, SCCmec V or SCCmec I, mecA gene, resistance to tobramycin, positive biofilm, and IS256+. In contrast to the healthy conjunctiva isolates, the discriminating markers were agr I, and resistance to chloramphenicol, ciprofloxacin, gatifloxacin and oxacillin. The discriminant biomarkers of ocular infection were examined in healthy conjunctiva isolates, and it was found that 3 healthy conjunctiva isolates [two with ST2 and another with ST9] (3/45, 6.66%) had similar genotypic and phenotypic characteristics to ocular infection isolates, therefore a small population from healthy conjunctiva could cause an ocular infection. These data suggest that the healthy conjunctiva isolates do not, in almost all cases, infect the eye due to their large genotypic and phenotypic difference with the ocular infection isolates. PMID:26275056

The 95ΔG mutation in the 5'untranslated region of the norA gene increases efflux activity in Staphylococcus epidermidis isolates.

PubMed

García-Gómez, Elizabeth; Jaso-Vera, Marcos E; Juárez-Verdayes, Marco A; Alcántar-Curiel, María D; Zenteno, Juan C; Betanzos-Cabrera, Gabriel; Peralta, Humberto; Rodríguez-Martínez, Sandra; Cancino-Díaz, Mario E; Jan-Roblero, Janet; Cancino-Diaz, Juan C

2017-02-01

In the Staphylococcus aureus ATCC25923 strain, the flqB mutation in the 5'untranslated region (5'UTR) of the norA gene causes increased norA mRNA expression and high efflux activity (HEA). The involvement of the norA gene 5'UTR in HEA has not been explored in S. epidermidis; therefore, we examined the function of this region in S. epidermidis clinical isolates. The selection of isolates with HEA was performed based on ethidium bromide (EtBr) MIC values and efflux efficiency (EF) using the semi-automated fluorometric method. The function of the 5'UTR was studied by quantifying the levels of norA expression (RT-qPCR) and by identifying 5'UTR mutations by sequence analysis. Only 10 isolates from a total of 165 (6.1%) had HEA (EtBr MIC = 300 μg/ml and EF ranged from 48.4 to 97.2%). Eight of 10 isolates with HEA had the 5'UTR 95 Δ G mutation. Isolates carrying the 95 Δ G mutation had higher levels of norA expression compared with those that did not. To corroborate that the 95 Δ G mutation is involved in HEA, a strain adapted to EtBr was obtained in vitro. This strain also presented the 95 Δ G mutation and had a high level of norA expression and EF, indicating that the 95 Δ G mutation is important for the HEA phenotype. The 95 Δ G mutation produces a different structure in the Shine-Dalgarno region, which may promote better translation of norA mRNA. To our knowledge, this is the first report to demonstrate the participation of the 5'UTR 95 Δ G mutation of the norA gene in the HEA phenotype of S. epidermidis isolates. Here, we propose that the efflux of EtBr is caused by an increment in the transcription and/or translation of the norA gene. Copyright © 2016 Elsevier Ltd. All rights reserved.

Microencapsulation of rifampicin for the prevention of endophthalmitis: In vitro release studies and antibacterial assessment.

PubMed

Lee, Mi Yeon; Bourgeois, Sandrine; Almouazen, Eyad; Pelletier, Jocelyne; Renaud, François; Fessi, Hatem; Kodjikian, Laurent

2016-05-30

Rifampicin encapsulated microparticles were designed for intraocular injection after cataract surgery to prevent postoperative endophthalmitis. Microparticles were formulated by emulsification diffusion method using poly(lactic acid-co-glycolic acid) (PLGA) as polymer in order to propose a new form of rifampicin that overcome its limitations in intraocular delivery. Depending on processing formulation, different types of microparticles were prepared, characterized and evaluated by in vitro release studies. Two types of microparticles were selected to get a burst release of rifampicin, to reach minimal inhibitory concentrations to inhibit 90% of Staphylococcus epidermidis mainly involved in postoperative endophthalmitis, combined with a sustained release to maintain rifampicin concentration over 24h. The antibacterial activity and antiadhesive property on intraocular lenses were evaluated on S. epidermidis. Microparticles, with a rapid rifampicin release profile, showed an effect towards bacteria development similar to free rifampicin over 48h. However, slow-release profile microparticles exhibited a similar antibacterial effect during the first 24h, and were able to destroy all the S epidermidis in the medium after 30h. The association of the two formulations allowed obtaining interesting antibacterial profile. Moreover, rifampicin-loaded microparticles have shown a very efficient anti-adherent effect of S. epidermidis on intraocular lenses at 24h. These results propose rifampicin microparticles as suitable for antibioprophylaxis of the postoperative endophthalmitis. Copyright © 2016 Elsevier B.V. All rights reserved.

High prevalence of Staphylococcus haemolyticus and Staphylococcus saprophyticus in environmental samples of a Tunisian hospital.

PubMed

Dziri, Raoudha; Klibi, Naouel; Lozano, Carmen; Ben Said, Leila; Bellaaj, Ridha; Tenorio, Carmen; Boudabous, Abdellatif; Ben Slama, Karim; Torres, Carmen

2016-06-01

The purpose of this study was to evaluate the rate of detection of coagulase negative staphylococci (CoNS) in environmental samples of 17 services in a Tunisian hospital, determining the antimicrobial resistance phenotypes and genotypes of recovered isolates. To our knowledge, this is the first study that determines the prevalence of CoNS with correlation of antibiotic resistance in the hospital environment in Tunisia. CoNS were obtained from 83 of the 200 tested samples (41.5%). Staphylococcus haemolyticus was the most prevalent species (45.8%), followed by S. saprophyticus (36.1%). The remaining CoNS species detected were S. epidermidis, S. cohnii, S. warneri, S. sciuri, S. simulans, S. pasteuri, S. arlettae, and S. xilosus. Methicillin-resistant CoNS were detected in 20 of the 200 tested samples (10%), and the mecA gene was demonstrated in 18 S. haemolyticus, one S. epidermidis and one S. saprophyticus isolates. Methicillin susceptible isolates were detected in 63 samples (31.5%). Antimicrobial resistance genes detected were as follows (number of isolates): erythromycin [msr(A) (n = 32); erm(C) (n = 8)], tetracycline [tet(K) and/or tet(M) (n = 21)], gentamicin [aac(6')-Ie-aph(2″)-Ia (n = 16)], kanamycin [(aph(3')-IIIa (n = 19)], tobramycin [ant(4')-Ia (n = 14)], and streptomycin [ant(6')-Ia (n = 3)]. The high frequency of detection of multi-drug-resistant CoNS in the hospital environment, especially S. haemolyticus and S. saprophyticus, is of relevance and could be due to cross-transmission between patients, staff, and environment. Copyright © 2016 Elsevier Inc. All rights reserved.

Efficacy of Detergent and Water Versus Bleach for the Disinfection of Direct Contact Ophthalmic Lenses

PubMed Central

Abbey, Ashkan M.; Gregori, Ninel Z.; Surapaneni, Krishna; Miller, Darlene

2014-01-01

Purpose While manufacturers recommend cleaning ophthalmic lenses with detergent and water and then a specific disinfectant, disinfectants are rarely used in ophthalmic practices. The aim of this pilot study was to evaluate the efficacy of detergent and water versus bleach, a recommended disinfectant, to eliminate common ocular bacteria and viruses from ophthalmic lenses. Methods Three bacterial strains (Staphylococcus epidermidis, Corynebacterium straitum, and methicillin-resistant Staphylococcus aureus (MRSA) and two viral strains (adenovirus and herpes simplex virus (HSV) type-1) were individually inoculated to 20 gonioscopy and laser lenses. Lenses were washed with detergent and water and then disinfected with 10% bleach. All lenses were cultured after inoculation, after detergent and water, and after the bleach. Bacterial cultures in thioglycollate broth were observed for 3 weeks and viral cultures for 2 weeks. The presence of viruses was also detected by multiplex polymerase chain reaction (PCR). Results All 20 lenses inoculated with Staphylococcus epidermidis, Corynebacterium straitum, adenovirus, and HSV-1 showed growth after inoculation, but no growth after detergent/water and after the bleach. All lenses showed positive HSV and adenovirus PCR after inoculation and negative PCR after detergent/water and after bleach. All MRSA contaminated lenses showed growth after inoculation and no growth after detergent and water. However, one lens showed positive growth after bleach. Conclusions Cleaning with detergent and water appeared to effectively eliminate bacteria and viruses from the surface of contaminated ophthalmic lenses. Further studies are warranted to design practical disinfection protocols that minimize lens damage. PMID:24747806

Distribution and Persistence of Staphylococcus and Micrococcus Species and Other Aerobic Bacteria on Human Skin1

PubMed Central

Kloos, Wesley E.; Musselwhite, Margaret S.

1975-01-01

The distribution of Staphylococcus and Micrococcus species and associated coryneform bacteria, Acinetobacter, Klebsiella, Enterobacter, Bacillus, and Streptomyces on skin was determined during October 1971 from samples collected on persons living in North Carolina and New Jersey. Persistence of these organisms on skin was estimated in temporal studies conducted during the period from June 1971 to June 1972 on persons living in North Carolina. Staphylococci and coryneforms were the most predominant and persistent bacteria isolated from the nares and axillae. Staphylococci, coryneforms, micrococci, and Bacillus were the most predominant and persistent bacteria isolated from the head, legs, and arms. Acinetobacters were most frequently isolated during the warmer months of the years. Staphylococcus aureus and S. epidermidis were the most predominant and persistent staphylococci isolated from the nares, whereas S. epidermidis and S. hominis were the most predominant and persistent staphylococci isolated from the axillae, head, legs, and arms. S. capitis was often isolated from the head and arms and S. haemolyticus was often isolated from the head, legs, and arms. S. simulans, S. xylosus, S. cohnii, S. saprophyticus, S. warneri, and an unclassified coagulase-positive species were only occasionally isolated from skin. Micrococcus luteus was the most predominant and persistent Micrococcus isolated from skin and preferred regions of the head, legs, and arms. M. varians was the second most frequent Micrococcus isolated. M. lylae, M. sedentarius, M. roseus, M. kristinae, and M. nishinomiyaensis were only occasionally isolated from skin. M. lylae was most frequently isolated during the colder months of the years. PMID:810086

Bacterial adherence to anodized titanium alloy

NASA Astrophysics Data System (ADS)

Pérez-Jorge Peremarch, C.; Pérez Tanoira, R.; Arenas, M. A.; Matykina, E.; Conde, A.; De Damborenea, J. J.; Gómez Barrena, E.; Esteban, J.

2010-11-01

The aim of this study was to evaluate Staphylococcus sp adhesion to modified surfaces of anodized titanium alloy (Ti-6Al-4V). Surface modification involved generation of fluoride-containing titanium oxide nanotube films. Specimens of Ti-6Al-4V alloy 6-4 ELI-grade 23- meets the requirements of ASTM F136 2002A (AMS 2631B class A1) were anodized in a mixture of sulphuric/hydrofluoric acid at 20 V for 5 and 60 min to form a 100 nm-thick porous film of 20 nm pore diameter and 230 nm-thick nanotube films of 100 nm in diameter. The amount of fluorine in the oxide films was of 6% and of 4%, respectively. Collection strains and six clinical strains each of Staphylococcus aureus and Staphylococcus epidermidis were studied. The adherence study was performed using a previously published protocol by Kinnari et al. The experiments were performed in triplicates. As a result, lower adherence was detected for collection strains in modified materials than in unmodified controls. Differences between clinical strains were detected for both species (p<0.0001, Kruskal-Wallis test), although global data showed similar results to that of collection strains (p<0.0001, Kruskal-Wallis test). Adherence of bacteria to modified surfaces was decreased for both species. The results also reflect a difference in the adherence between S. aureus and S. epidermidis to the modified material. As a conclusion, not only we were able to confirm the decrease of adherence in the modified surface, but also the need to test multiple clinical strains to obtain more realistic microbiological results due to intraspecies differences.

Communications of Staphylococcus aureus and non-aureus Staphylococcus species from bovine intramammary infections and teat apex colonization.

PubMed

Mahmmod, Yasser S; Klaas, Ilka Christine; Svennesen, Line; Pedersen, Karl; Ingmer, Hanne

2018-05-16

The role of non-aureus staphylococci (NAS) in the risk of acquisition of intramammary infections with Staphylococcus aureus is vague and still under debate. The objectives of this study were to (1) investigate the distribution patterns of NAS species from milk and teat skin in dairy herds with automatic milking systems, and (2) examine if the isolated NAS influences the expression of S. aureus virulence factors controlled by the accessory gene regulator (agr) quorum sensing system. In 8 herds, 14 to 20 cows with elevated somatic cell count were randomly selected for teat skin swabbing and aseptic quarter foremilk samples from right hind and left front quarters. Teat skin swabs were collected using the modified wet-dry method and milk samples were taken aseptically for bacterial culture. Colonies from quarters with suspicion of having NAS in milk or teat skin samples (or both) were subjected to MALDI-TOF assay for species identification. To investigate the interaction between S. aureus and NAS, 81 isolates NAS were subjected to a qualitative β-galactosidase reporter plate assay. In total, 373 NAS isolates were identified representing 105 from milk and 268 from teat skin of 284 quarters (= 142 cows). Sixteen different NAS species were identified, 15 species from teat skin and 10 species from milk. The most prevalent NAS species identified from milk were Staphylococcus epidermidis (50%), Staphylococcus haemolyticus (15%), and Staphylococcus chromogenes (11%), accounting for 76%. Meanwhile, the most prevalent NAS species from teat skin were Staphylococcus equorum (43%), S. haemolyticus (16%), and Staphylococcus cohnii (14%), accounting for 73%. Using reporter gene fusions monitoring transcriptional activity of key virulence factors and regulators, we found that out of 81 supernatants of NAS isolates, 77% reduced expression of hla, encoding a-hemolysin, 70% reduced expression of RNAIII, the key effector molecule of agr, and 61% reduced expression of spa encoding protein A of S. aureus, respectively. Our NAS isolates showed 3 main patterns: (1) downregulation effect such as S. chromogenes (milk) and Staphylococcus xylosus (milk and teat), (2) no effect such as Staphylococcus sciuri (teat) and S. vitulinus (teat), and the third pattern (c) variable effect such as S. epidermidis (milk and teat) and S. equorum (milk and teat). The pattern of cross-talk between NAS species and S. aureus virulence genes varied according to the involved NAS species, habitat type, and herd factors. The knowledge of how NAS influences S. aureus virulence factor expression could explain the varying protective effect of NAS on S. aureus intramammary infections. Copyright © 2018 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Activity of plant flavonoids against antibiotic-resistant bacteria.

PubMed

Xu, H X; Lee, S F

2001-02-01

Thirty eight plant-derived flavonoids representing seven different structural groups were tested for activities against antibiotic-resistant bacteria using the disc-diffusion assay and broth dilution assay. Among the flavonoids examined, four flavonols (myricetin, datiscetin, kaempferol and quercetin) and two -flavones (flavone and luteolin) exhibited inhibitory activity against methicillin-resistant Staphylococcus aureus (MRSA). Myricetin was also found to inhibit the growth of multidrug-resistant Burkholderia -cepacia, vancomycin-resistant enterococci (VRE) and other medically important organisms such as -Klebsiella pneumoniae and Staphylococcus epidermidis. Myricetin was bactericidal to B. cepacia. The results of the radiolabel incorporation assay showed that myricetin inhibited protein synthesis by -B. cepacia. The structure-activity relationship of these flavonoids is discussed. Copyright 2001 John Wiley & Sons, Ltd.

The Evaluation of Methicillin Resistance in Staphylococcus aboard the International Space Station

NASA Technical Reports Server (NTRS)

Ott, C. M.; Bassinger, V. J.; Fontenot, S. L.; Castro, V. A.; Pierson, D. L.

2005-01-01

The International Space Station (ISS) represents a semi-closed environment with a high level of crewmember interaction. As community-acquired methicillin-resistant Staphylococcus aureus (MRSA) has emerged as a health concern in environments with susceptible hosts in close proximity, an evaluation of isolates of clinical and environmental Staphylococcus aureus and coagulase negative Staphylococcus was performed to determine if this trend was also present in astronauts aboard ISS or the space station itself. Rep-PCR fingerprinting analysis of archived ISS isolates confirmed our earlier studies indicating a transfer of S. aureus between crewmembers. In addition, this fingerprinting also indicated a transfer between crewmembers and their environment. While a variety of S. aureus were identified from both the crewmembers and the environment, phenotypic evaluations indicated minimal methicillin resistance. However, positive results for the Penicillin Binding Protein, indicative of the presence of the mecA gene, were detected in multiple isolates of archived Staphylococcus epidermidis and Staphylococcus haemolyticus. Phenotypic analysis of these isolates confirmed their resistance to methicillin. While MRSA has not been isolated aboard ISS, the potential exists for the transfer of the gene, mecA, from coagulase negative environmental Staphylococcus to S. aureus creating MRSA strains. This study suggests the need to expand environmental monitoring aboard long duration exploration spacecraft to include antibiotic resistance profiling.

Medium-Induced Antagonistic Behavior in Staphylococcus Aureus.

ERIC Educational Resources Information Center

Benathen, Isaiah A.

1992-01-01

Antagonism is the production of substances by microorganisms that inhibit or prevent the growth of other bacteria. This paper demonstrates the antagonistic behavior of gram-positive coccus on the B. subtilis and Enterococcus faecalis gram-positive microorganisms, showing that the process of antagonism is sometimes dependent on the nutritional…

Single-cell force spectroscopy of the medically important Staphylococcus epidermidis-Candida albicans interaction

NASA Astrophysics Data System (ADS)

Beaussart, Audrey; Herman, Philippe; El-Kirat-Chatel, Sofiane; Lipke, Peter N.; Kucharíková, Soňa; van Dijck, Patrick; Dufrêne, Yves F.

2013-10-01

Despite the clinical importance of bacterial-fungal interactions, their molecular details are poorly understood. A hallmark of such medically important interspecies associations is the interaction between the two nosocomial pathogens Staphylococcus aureus and Candida albicans, which can lead to mixed biofilm-associated infections with enhanced antibiotic resistance. Here, we use single-cell force spectroscopy (SCFS) to quantify the forces engaged in bacterial-fungal co-adhesion, focusing on the poorly investigated S. epidermidis-C. albicans interaction. Force curves recorded between single bacterial and fungal germ tubes showed large adhesion forces (~5 nN) with extended rupture lengths (up to 500 nm). By contrast, bacteria poorly adhered to yeast cells, emphasizing the important role of the yeast-to-hyphae transition in mediating adhesion to bacterial cells. Analysis of mutant strains altered in cell wall composition allowed us to distinguish the main fungal components involved in adhesion, i.e. Als proteins and O-mannosylations. We suggest that the measured co-adhesion forces are involved in the formation of mixed biofilms, thus possibly as well in promoting polymicrobial infections. In the future, we anticipate that this SCFS platform will be used in nanomedicine to decipher the molecular mechanisms of a wide variety of pathogen-pathogen interactions and may help in designing novel anti-adhesion agents.

18 GHz electromagnetic field induces permeability of Gram-positive cocci

PubMed Central

Nguyen, The Hong Phong; Shamis, Yury; Croft, Rodney J.; Wood, Andrew; McIntosh, Robert L.; Crawford, Russell J.; Ivanova, Elena P.

2015-01-01

The effect of electromagnetic field (EMF) exposures at the microwave (MW) frequency of 18 GHz, on four cocci, Planococcus maritimus KMM 3738, Staphylococcus aureus CIP 65.8T, S. aureus ATCC 25923 and S. epidermidis ATCC 14990T, was investigated. We demonstrate that exposing the bacteria to an EMF induced permeability in the bacterial membranes of all strains studied, as confirmed directly by transmission electron microscopy (TEM), and indirectly via the propidium iodide assay and the uptake of silica nanospheres. The cells remained permeable for at least nine minutes after EMF exposure. It was shown that all strains internalized 23.5 nm nanospheres, whereas the internalization of the 46.3 nm nanospheres differed amongst the bacterial strains (S. epidermidis ATCC 14990T~ 0%; Staphylococcus aureus CIP 65.8T S. aureus ATCC 25923, ~40%; Planococcus maritimus KMM 3738, ~80%). Cell viability experiments indicated that up to 84% of the cells exposed to the EMF remained viable. The morphology of the bacterial cells was not altered, as inferred from the scanning electron micrographs, however traces of leaked cytosolic fluids from the EMF exposed cells could be detected. EMF-induced permeabilization may represent an innovative, alternative cell permeability technique for applications in biomedical engineering, cell drug delivery and gene therapy. PMID:26077933

Electrostatic immobilization of antimicrobial peptides on polyethylenimine and their antibacterial effect against Staphylococcus epidermidis.

PubMed

Hernandez-Montelongo, J; Corrales Ureña, Y R; Machado, D; Lancelloti, M; Pinheiro, M P; Rischka, K; Lisboa-Filho, P N; Cotta, M A

2018-04-01

Staphylococcus epidermidis is a gram-positive bacterium, and one of the most prevalent causes of nosocomial infections due to its strong ability to form biofilms on catheters and surgical implants. Here we explore the antimicrobial properties of Tet-124 peptides, which are part of the innate defense against different multicellular organisms in nature. Two different Tet-124 peptides were immobilized on a polyethylenimine (PEI) film to determine their impact on the antimicrobial properties: KLWWMIRRW (Tet-124), which contains only natural amino acids, and KLWWMIRRWG-(F-Br)-G (F-Br = 4-Bromophenylalanine), a modified Tet-124 sequence with the addition of an unnatural amino acid. The immobilization was obtained as a result of the electrostatic interaction between PEI amino groups and the C-terminal carboxylic groups of tryptophan and glycine amino acids of Tet-124 and Tet-124-Br peptides, respectively. The process was monitored and studied by water contact angle, Atomic Force Microscopy (AFM), X-ray Photoelectron Spectroscopy (XPS) and Quartz Crystal Microbalance with Dissipation (QCM-D) measurements. The antibacterial effect of our samples against S. epidermis was evaluated by the spread plate counting method, and cytotoxicity was tested using fibroblast cultures. Our results indicate the feasibility to immobilize electrostatically both Tet-124 peptides for biomedical applications. Copyright © 2018 Elsevier B.V. All rights reserved.

Evaluation of CAMP-Like Effect, Biofilm Formation, and Discrimination of Candida africana from Vaginal Candida albicans Species

PubMed Central

Bordbar, Mahboubeh; Nouraei, Hasti; Khodadadi, Hossein

2017-01-01

Candida africana as a species recovered from female genital specimens is highly close to C. albicans. The present study was conducted to discriminate C. africana from presumptive vaginal C. albicans strains by molecular assay and evaluate their hemolysin activity, biofilm formation, and cohemolytic effect (CAMP) with vaginal bacterial flora. A total of 110 stock vaginal C. albicans isolates were examined by HWP1 gene amplification. Hemolysin activity and the ability of biofilm formation were evaluated by blood plate assay and visual detection methods, respectively. Staphylococcus aureus, Staphylococcus epidermidis, and Streptococcus agalactiae were used to evaluate the CAMP-like effects in Sabouraud blood agar media. Based on the size of the amplicons (941 bp), all isolates were identified as C. albicans. All samples were able to produce beta-hemolysin. Moreover, 69 out of 110 of the isolates (62.7%) were biofilm-positive, 54 out of 110 Candida isolates (49%) demonstrated cohemolytic effects with S. agalactiae, and 48 out of 110 showed this effect with S. aureus (43.6%). All isolates were CAMP-negative with S. epidermidis. We detected all isolates as Candida albicans and almost half of the isolates were CAMP-positive with S. aureus and S. agalactiae, suggesting that these bacteria increase the pathogenicity of Candida in vaginal candidiasis. PMID:29318048

Changing Patterns of Blood Borne Sepsis in Special Care Baby Unit, Khoula Hospital

PubMed Central

Gupta, Bhaskar; El Amin, Eisa

2010-01-01

Objectives Infection is a frequent and important cause of morbidity and mortality in neonatal units all over the world. Over the years, there has been a shift in the microorganisms responsible for neonatal septicemia. This study aims to analyze the changing patterns of blood borne organisms in the neonatal unit. Methods This retrospective study was undertaken at the neonatal intensive care unit of Khoula Hospital in Muscat, Sultanate of Oman to analyze the incidence of blood borne sepsis and its changing pattern from 1997-2000. Results Out of a total 2181 admissions to the neonatal intensive care unit, 71 (3.25%) babies had positive blood culture. A reduction in the incidence of blood borne sepsis with changing patterns of organisms was seen over the period of four years with incidence of Group B Streptococcus declining from 34% in 1997-1998 to 17.8% in 1999-2000 and the incidence of CONS (Staphylococcus epidermidis) increasing from 20% in 1997-1998 to 35% in 1999-2000. Conclusion Overall, due to survival and prolonged hospitalization of extremely low birth weight babies who need frequent invasive procedures, and the use of powerful antibiotics, the incidence of Staphylococcus epidermidis which was previously thought to be non pathogenic has increased over the years in neonatal intensive care units. PMID:22125709

18 GHz electromagnetic field induces permeability of Gram-positive cocci.

PubMed

Nguyen, The Hong Phong; Shamis, Yury; Croft, Rodney J; Wood, Andrew; McIntosh, Robert L; Crawford, Russell J; Ivanova, Elena P

2015-06-16

The effect of electromagnetic field (EMF) exposures at the microwave (MW) frequency of 18 GHz, on four cocci, Planococcus maritimus KMM 3738, Staphylococcus aureus CIP 65.8(T), S. aureus ATCC 25923 and S. epidermidis ATCC 14990(T), was investigated. We demonstrate that exposing the bacteria to an EMF induced permeability in the bacterial membranes of all strains studied, as confirmed directly by transmission electron microscopy (TEM), and indirectly via the propidium iodide assay and the uptake of silica nanospheres. The cells remained permeable for at least nine minutes after EMF exposure. It was shown that all strains internalized 23.5 nm nanospheres, whereas the internalization of the 46.3 nm nanospheres differed amongst the bacterial strains (S. epidermidis ATCC 14990(T) ~  0%; Staphylococcus aureus CIP 65.8(T) S. aureus ATCC 25923, ~40%; Planococcus maritimus KMM 3738, ~ 80%). Cell viability experiments indicated that up to 84% of the cells exposed to the EMF remained viable. The morphology of the bacterial cells was not altered, as inferred from the scanning electron micrographs, however traces of leaked cytosolic fluids from the EMF exposed cells could be detected. EMF-induced permeabilization may represent an innovative, alternative cell permeability technique for applications in biomedical engineering, cell drug delivery and gene therapy.

Isolation and identification of symbiotic bacteria from the skin, mouth, and rectum of wild and captive tree shrews.

PubMed

Li, Gui; Lai, Ren; Duan, Gang; Lyu, Long-Bao; Zhang, Zhi-Ye; Liu, Huang; Xiang, Xun

2014-11-18

Endosymbionts influence many aspects of their hosts' health conditions, including physiology, development, immunity, metabolism, etc. Tree shrews (Tupaia belangeri chinensis) have attracted increasing attention in modeling human diseases and therapeutic responses due to their close relationship with primates. To clarify the situation of symbiotic bacteria from their body surface, oral cavity, and anus, 12 wild and 12 the third generation of captive tree shrews were examined. Based on morphological and cultural characteristics, physiological and biochemical tests, as well as the 16S rDNA full sequence analysis, 12 bacteria strains were isolated and identified from the wild tree shrews: body surface: Bacillus subtilis (detection rate 42%), Pseudomonas aeruginosa (25%), Staphlococcus aureus (33%), S. Epidermidis (75%), Micrococcus luteus (25%), Kurthia gibsonii (17%); oral cavity: Neisseria mucosa (58%), Streptococcus pneumonia (17%); anus: Enterococcus faecalis (17%), Lactococus lactis (33%), Escherichia coli (92%), Salmonella typhosa (17%); whereas, four were indentified from the third generation captive tree shrews: body surface: S. epidermidis (75%); oral cavity: N.mucosa (67%); anus: L. lactis (33%), E. coli (100%). These results indicate that S. epidermidis, N. mucosa, L. lactis and E. coli were major bacteria in tree shrews, whereas, S. aureus, M. luteus, K. gibsonii, E. faecalis and S. typhosa were species-specific flora. This study facilitates the future use of tree shrews as a standard experimental animal and improves our understanding of the relationship between endosymbionts and their hosts.

Antimicrobial effects of Finnish plant extracts containing flavonoids and other phenolic compounds.

PubMed

Rauha, J P; Remes, S; Heinonen, M; Hopia, A; Kähkönen, M; Kujala, T; Pihlaja, K; Vuorela, H; Vuorela, P

2000-05-25

Plant phenolics, especially dietary flavonoids, are currently of growing interest owing to their supposed functional properties in promoting human health. Antimicrobial screening of 13 phenolic substances and 29 extracts prepared from Finnish plant materials against selected microbes was conducted in this study. The tests were carried out using diffusion methods with four to nine microbial species (Aspergillus niger, Bacillus subtilis, Candida albicans, Escherichia coli, Micrococcus luteus, Pseudomonas aeruginosa, Saccharomyces cerevisiae, Staphylococcus aureus and Staphylococcus epidermidis). Flavone, quercetin and naringenin were effective in inhibiting the growth of the organisms. The most active plant extracts were purple loosestrife (Lythrum salicaria L.) against Candida albicans, meadowsweet (Filipendula ulmaria (L.) Maxim.), willow herb (Epilobium angustifolium L.), cloudberry (Rubus chamaemorus L.) and raspberry (Rubus idaeus L.) against bacteria, and white birch (Betula pubescens Ehrh.), pine (Pinus sylvestris L.) and potato (Solanum tuberosum. L.) against gram-positive Staphylococcus aureus.

Vesicle formation as a result of interaction between polymorphonuclear neutrophils and Staphylococcus aureus biofilm.

PubMed

Chebotar, Igor' V; Konchakova, Evgenia D; Maianskii, Andrey N

2013-08-01

Staphylococcus aureus, a major opportunistic pathogen, is a leading cause of biofilm-related infections in clinical practice. Staphylococcal biofilms are highly resistant to antibacterial medicines and immune effector cells. The main result of our work is the discovery of nano-vesicles in the supernatant of the human neutrophil-S. aureus biofilm system. We also found that phospholipase C treatment causes complete destruction of these vesicles. While the addition of proteinase K led to a partial structural disorganization of the vesicles, DNase treatment did not influence the vesicle structure. These observations allowed us to conclude that phospholipids and proteins play a structure-forming role in the formation of these nano-vesicles. The vesicles demonstrated anti-biofilm activities when tested against Staphylococcus epidermidis (strains 178M and 328/5) biofilms, but were ineffective for S. aureus (strains 5983/2, 5663 and 18A) biofilms.

Influence of a new surface modification of intraocular lenses with fluoroalkylsilan on the adherence of endophthalmitis-causing bacteria in vitro.

PubMed

Kienast, Antonia; Kämmerer, Regine; Weiss, Claudia; Klinger, Matthias; Menz, Dirk-Henning; Dresp, Joachim; Ohgke, Helge; Solbach, Werner; Laqua, Horst; Hoerauf, Hans

2006-09-01

Dynasilan is a fluoroalkylsilan that is able to interact with surface active centres on intraocular lenses (IOL), offering a new way for surface modification of different IOL materials. The purpose of this in vitro study was to investigate the influence of this new surface modification on the adherence of two typical endophthalmitis causing bacteria (Staphylococcus epidermidis, Propionibacterium acnes). In a pilot experiment, the effect of Dynasilan coating on the adherence of S. epidermidis was tested on glass slides. Forty-two Dynasilan-modified and 42 unmodified IOL (14 PMMA, 14 silicone and 14 hydrogel) were incubated at 37 degrees C in brain heart infusion broth (10(8) CFU/ml) with either S. epidermidis for 24 h or with P. acnes for 1 h. Subsequently, the adherent bacteria were resuspended using ultrasonification at 35 kHz for 3x45 s. After dilution series and incubation at 37 degrees C on Petri dishes for 24 h and 3 days, respectively, the colonies were counted. In the pilot experiment, a markedly lower number of adherent S. epidermidis was observed on Dynasilan-modified glass slides. Of all IOL materials incubated with S. epidermidis, those modified with Dynasilan showed a lower mean number of adherent bacteria (mean 1.37x10(7); SD 2.37x10(7)) than those untreated (2.43x10(7); SD 3.04x10(7)). IOLs incubated with P. acnes showed a significantly lower mean number of adherent bacteria of 2.51x10(4) (SD 2.71x10(4)) on Dynasilan-modified IOLs versus 6.27x10(4) (SD 7.70x10(4)) on untreated IOLs. The presented in vitro results indicate that Dynasilan surface modification is able to reduce the adherence of S. epidermidis and P. acnes on all IOL materials tested. Further studies regarding the stability of this modification and its biocompatibility must be performed.

Modeling Staphylococcus epidermidis-Induced Non-Unions: Subclinical and Clinical Evidence in Rats

PubMed Central

Lovati, Arianna Barbara; Romanò, Carlo Luca; Bottagisio, Marta; Monti, Lorenzo; De Vecchi, Elena; Previdi, Sara; Accetta, Riccardo; Drago, Lorenzo

2016-01-01

S. epidermidis is one of the leading causes of orthopaedic infections associated with biofilm formation on implant devices. Open fractures are at risk of S. epidermidis transcutaneous contamination leading to higher non-union development compared to closed fractures. Although the role of infection in delaying fracture healing is well recognized, no in vivo models investigated the impact of subclinical low-grade infections on bone repair and non-union. We hypothesized that the non-union rate is directly related to the load of this commonly retrieved pathogen and that a low-grade contamination delays the fracture healing without clinically detectable infection. Rat femurs were osteotomized and stabilized with plates. Fractures were infected with a characterized clinical-derived methicillin-resistant S. epidermidis (103, 105, 108 colony forming units) and compared to uninfected controls. After 56 days, bone healing and osteomyelitis were clinically assessed and further evaluated by micro-CT, microbiological and histological analyses. The biofilm formation was visualized by scanning electron microscopy. The control group showed no signs of infection and a complete bone healing. The 103 group displayed variable response to infection with a 67% of altered bone healing and positive bacterial cultures, despite no clinical signs of infection present. The 105 and 108 groups showed severe signs of osteomyelitis and a non-union rate of 83–100%, respectively. The cortical bone reaction related to the periosteal elevation in the control group and the metal scattering detected by micro-CT represented limitations of this study. Our model showed that an intra-operative low-grade S. epidermidis contamination might prevent the bone healing, even in the absence of infectious signs. Our findings also pointed out a dose-dependent effect between the S. epidermidis inoculum and non-union rate. This pilot study identifies a relevant preclinical model to assess the role of subclinical infections in orthopaedic and trauma surgery and to test specifically designed diagnostic, prevention and therapeutic strategies. PMID:26796958

Thin magnesium layer confirmed as an antibacterial and biocompatible implant coating in a co‑culture model.

PubMed

Zaatreh, Sarah; Haffner, David; Strauss, Madlen; Dauben, Thomas; Zamponi, Christiane; Mittelmeier, Wolfram; Quandt, Eckhard; Kreikemeyer, Bernd; Bader, Rainer

2017-04-01

Implant-associated infections commonly result from biofilm‑forming bacteria and present severe complications in total joint arthroplasty. Therefore, there is a requirement for the development of biocompatible implant surfaces that prevent bacterial biofilm formation. The present study coated titanium samples with a thin, rapidly corroding layer of magnesium, which were subsequently investigated with respect to their antibacterial and cytotoxic surface properties using a Staphylococcus epidermidis (S. epidermidis) and human osteoblast (hOB) co‑culture model. Primary hOBs and S. epidermidis were co‑cultured on cylindrical titanium samples (Ti6Al4V) coated with pure magnesium via magnetron sputtering (5 µm thickness) for 7 days. Uncoated titanium test samples served as controls. Vital hOBs were identified by trypan blue staining at days 2 and 7. Planktonic S. epidermidis were quantified by counting the number of colony forming units (CFU). The quantification of biofilm‑bound S. epidermidis on the surfaces of test samples was performed by ultrasonic treatment and CFU counting at days 2 and 7. The number of planktonic and biofilm‑bound S. epidermidis on the magnesium‑coated samples decreased by four orders of magnitude when compared with the titanium control following 7 days of co‑culture. The number of vital hOBs on the magnesium‑coated samples was observed to increase (40,000 cells/ml) when compared with the controls (20,000 cells/ml). The results of the present study indicate that rapidly corroding magnesium‑coated titanium may be a viable coating material that possesses antibacterial and biocompatible properties. A co‑culture test is more rigorous than a monoculture study, as it accounts for confounding effects and assesses additional interactions that are more representative of in vivo situations. These results provide a foundation for the future testing of this type of surface in animals.

Thin magnesium layer confirmed as an antibacterial and biocompatible implant coating in a co-culture model

PubMed Central

Zaatreh, Sarah; Haffner, David; Strauss, Madlen; Dauben, Thomas; Zamponi, Christiane; Mittelmeier, Wolfram; Quandt, Eckhard; Kreikemeyer, Bernd; Bader, Rainer

2017-01-01

Implant-associated infections commonly result from biofilm-forming bacteria and present severe complications in total joint arthroplasty. Therefore, there is a requirement for the development of biocompatible implant surfaces that prevent bacterial biofilm formation. The present study coated titanium samples with a thin, rapidly corroding layer of magnesium, which were subsequently investigated with respect to their antibacterial and cytotoxic surface properties using a Staphylococcus epidermidis (S. epidermidis) and human osteoblast (hOB) co-culture model. Primary hOBs and S. epidermidis were co-cultured on cylindrical titanium samples (Ti6Al4V) coated with pure magnesium via magnetron sputtering (5 µm thickness) for 7 days. Uncoated titanium test samples served as controls. Vital hOBs were identified by trypan blue staining at days 2 and 7. Planktonic S. epidermidis were quantified by counting the number of colony forming units (CFU). The quantification of biofilm-bound S. epidermidis on the surfaces of test samples was performed by ultrasonic treatment and CFU counting at days 2 and 7. The number of planktonic and biofilm-bound S. epidermidis on the magnesium-coated samples decreased by four orders of magnitude when compared with the titanium control following 7 days of co-culture. The number of vital hOBs on the magnesium-coated samples was observed to increase (40,000 cells/ml) when compared with the controls (20,000 cells/ml). The results of the present study indicate that rapidly corroding magnesium-coated titanium may be a viable coating material that possesses antibacterial and biocompatible properties. A co-culture test is more rigorous than a monoculture study, as it accounts for confounding effects and assesses additional interactions that are more representative of in vivo situations. These results provide a foundation for the future testing of this type of surface in animals. PMID:28260022

Synthesis and structure-activity relationship of amidine derivatives of 3,4-ethylenedioxythiophene as novel antibacterial agents.

PubMed

Stolić, Ivana; Čipčić Paljetak, Hana; Perić, Mihaela; Matijašić, Mario; Stepanić, Višnja; Verbanac, Donatella; Bajić, Miroslav

2015-01-27

Current antibacterial chemotherapeutics are facing an alarming increase in bacterial resistance pressuring the search for novel agents that would expand the available therapeutic arsenal against resistant bacterial pathogens. In line with these efforts, a series of 9 amidine derivatives of 3,4-ethylenedioxythiophene were synthesized and, together with 18 previously synthesized analogs, evaluated for their relative DNA binding affinity, in vitro antibacterial activities and preliminary in vitro safety profile. Encouraging antibacterial activity of several subclasses of tested amidine derivatives against Gram-positive (including resistant MRSA, MRSE, VRE strains) and Gram-negative bacterial strains was observed. The bis-phenyl derivatives were the most antibacterially active, while compound 19 from bis-benzimidazole class exhibited the widest spectrum of activity (with MIC of 4, 2, 0.5 and ≤0.25 μg/ml against laboratory strains of Staphyloccocus aureus, Streptococcus pneumoniae, Streptococcus pyogenes, Moraxella catarrhalis, respectively and 4-32 μg/ml against clinical isolates of sensitive and resistant S. aureus, Staphylococcus epidermidis and Enterococcus faecium) and also demonstrated the strongest DNA binding affinity (ΔTm of 15.4 °C). Asymmetrically designed compounds and carboxamide-amidines were, in general, less active. Molecular docking indicated that the shape of the 3,4-ethylenedioxythiophene derivatives and their ability to form multiple electrostatic and hydrogen bonds with DNA, corresponds to the binding modes of other minor-groove binders. Herein reported results encourage further investigation of this class of compounds as novel antibacterial DNA binding agents. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

Bioactive metabolites from the endophytic fungus Ampelomyces sp. isolated from the medicinal plant Urospermum picroides.

PubMed

Aly, Amal H; Edrada-Ebel, Ruangelie; Wray, Victor; Müller, Werner E G; Kozytska, Svitlana; Hentschel, Ute; Proksch, Peter; Ebel, Rainer

2008-05-01

Extracts of cultures grown in liquid or on solid rice media of the fungal endophyte Ampelomyces sp. isolated from the medicinal plant Urospermum picroides exhibited considerable cytotoxic activity when tested in vitro against L5178Y cells. Chromatographic separation yielded 14 natural products that were unequivocally identified based on their 1H and 13C NMR as well as mass spectra and comparison with previously published data. Six compounds (2, 4, 5, 7, 9 and 11) were natural products. Both fungal extracts differed considerably in their secondary metabolites. The extract obtained from liquid cultures afforded a pyrone (2) and sulfated anthraquinones (7 and 9) along with the known compounds 1, 3, 6 and 8. When grown on solid rice medium the fungus yielded three compounds 4, 5 and 11 in addition to several known metabolites including 6, 8, 10, 12, 13 and 14. Compounds 4, 8 and 10 showed the strongest cytotoxic activity against L5178Y cells with EC50 values ranging from 0.2-7.3microg/ml. Furthermore, 8 and 10 displayed antimicrobial activity against the Gram-positive pathogens, Staphylococcus aureus, S. epidermidis and Enterococcus faecalis at minimal inhibitory concentrations (MIC) of 12.5microg/ml and 12.5-25microg/ml, respectively. Interestingly, 6 and 8 were also identified as constituents of an extract derived from a healthy plant sample of the host plant U. picroides thereby indicating that the production of bioactive natural products by the endophyte proceeds also under in situ conditions within the host plant.

Antibacterial properties studies of trunk barks of Terminalia ivorensis, a commercial and medicinal species on some methicillin-resistant Staphylococci species strains.

PubMed

Coulibaly, K; Zirihi, G N; Guessennd-Kouadio, N; Oussou, K R; Dosso, M

2014-09-01

Methicillin-resistant Staphylococcus aureus, Staphylococcus epidermidis and coagulase-negative Staphylococcus infections are a worldwide concern. Terminalia ivorensis, of Combretaceae family plant, is widely used traditional medicinal in Côte d'Ivoire to treat dermal diseases (affection in which Staphylococci are implied) including local inflammation and also to treat voice-loss. This study focused to investigate the effect in vitro of the extracts of trunk barks of Terminalia ivorensis on some methicillin/oxacillin-resistant strains of Staphylococcus aureus, S. epidermidis, coagulase-negative S. and reference strain of S. aureus ATCC 25923. Antibacterial activity of aqueous, 70% ethanolic 70% and aqueous residue extracts was assessed using agar disc-diffusion method and liquid medium microdilution method in 96 multi-well micro-titer plates. This method led us to determine minimum inhibition concentration (M.I.C.) and minimum bactericidal concentration (M.B.C.). The presence of chemical groups major was detected qualitatively. Aqueous and 70% ethanolic 70% extracts showed significant activity against all the bacteria except aqueous residue when compared with the standard antibiotic oxacillin (5 µg/ml). M.I.C. for aqueous and 70% ethanolic 70% extracts ranged from 0,83-16,67 mg/ml and 0,156-13,33 mg/ml respectively. Viable cell determination revealed the bactericidal nature of the two barks extracts. The 70% ethanolic 70% extract exhibited the highest activity according to the M.B.C. values. The phytochemical analysis indicates the presence of tannins, saponins, flavonoids, terpen/sterols, coumarins, polyphenols and traces of alkaloid. The in-vitro antibacterial efficacy shown by the barks of this plant and his lushness in chimical compounds, would justify use of this one in the traditional treatment of some diseases of microbial origin. These compounds could be suggested to provide alternative solution to the development of new therapeutic agents.

Bacterial adhesion to orthopedic implant polymers.

PubMed

Barton, A J; Sagers, R D; Pitt, W G

1996-03-01

The degradable polymers poly(orthoester) (POE), poly(L-lactic acid) (PLA), and the nondegradable polymers polysulfone (PSF), polyethylene (PE), and poly(ether ether ketone) (PEEK) were exposed to cultures of Staphylococcus epidermidis, Pseudomonas aeruginosa, or Escherichia coli. Bacteria washed and resuspended in phosphate buffered saline (PBS) adhered to polymers in amounts nearly twice those of bacteria that were left in their growth medium, tryptic soy broth (TSB). In TSB, there was variation in adhesion from species to species, but no significant variation from polymer to polymer within one species. In PBS there were significant differences in the amounts of bacteria adhering to the various polymers with the exception, of S. epidermidis, which had similar adhesion to all polymers. As a whole, P. aeruginosa was the most adherent while S. epidermidis was the least adherent. The estimated values of the free energy of adhesion (delta Fadh) correlated with the amount of adherent P. aeruginosa. When POE, PLA, and PSF were exposed to hyaluronic acid (HA) before exposure to the bacteria, there was 50% more adhesion of E. coli and P. aeruginosa on POE and PLA. With respect to bacterial adhesion, the biodegradable polymers (POE and PLA) in general were not significantly different from the nondegradable polymers.

Phenolic glycosides and ionone glycoside from the stem of Sargentodoxa cuneata.

PubMed

Chang, Jun; Case, Ryan

2005-12-01

Four phenolic glycosides, cuneatasides A-D (1-4), and one ionone glycoside cuneataside E (5), together with seven known phenolic compounds (6-12) were isolated from the water-soluble constituents of the stem of Sargentodoxa cuneata (Sargentodoxaceae). Their structures were elucidated by spectroscopic analysis. In vitro tests for antimicrobial activity showed compounds 1 and 2 to possess significant activity against two Gram-positive organisms, Staphylococcus aureus and Micrococcus epidermidis.

Antimicrobial activity of ceftaroline and comparator agents when tested against numerous species of coagulase-negative Staphylococcus causing infection in US hospitals.

PubMed

Sader, Helio S; Farrell, David J; Flamm, Robert K; Streit, Jennifer M; Mendes, Rodrigo E; Jones, Ronald N

2016-05-01

A total of 1593 coagulase-negative staphylococci (CoNS) considered clinically significant were collected from 71 US medical centers in 2013-2014 and tested for susceptibility by CLSI broth microdilution methods. Species identification was performed by matrix-assisted laser desorption ionization-time-of-flight mass spectrometry. Overall, 59.7% of isolates were oxacillin resistant (MRCoNS). Ceftaroline (MIC50/90, 0.25/0.5μg/mL) inhibited 99.2% of CoNS at ≤1μg/mL (susceptible breakpoint for Staphylococcus aureus), including 98.7% of MRCoNS, and the highest ceftaroline MIC value was 2μg/mL (13 isolates). Staphylococcus epidermidis represented 60.3% of the CoNS collection and was highly susceptible to ceftaroline (MIC50/90, 0.25/0.5μg/mL, 99.9% inhibited at ≤1μg/mL). All isolates of Staphylococcus capitis, Staphylococcus caprae, Staphylococcus hominis, Staphylococcus lugdunensis, Staphylococcus pettenkoferi, Staphylococcus simulans, and Staphylococcus warneri (MIC50/90, 0.06-0.25/0.25-0.5μg/mL) were inhibited at ceftaroline MIC of ≤1μg/mL. Staphylococcus haemolyticus represented only 4.8%, was atypically less susceptible to ceftaroline (MIC50/90, 0.5/2μg/mL, 87.0% inhibited at ≤1μg/mL), and accounted for 76.9% (10/13) of isolates with ceftaroline MIC >1μg/mL. Copyright © 2016 Elsevier Inc. All rights reserved.

Polyhexamethylene guanidine hydrochloride shows bactericidal advantages over chlorhexidine digluconate against ESKAPE bacteria.

PubMed

Zhou, Zhongxin; Wei, Dafu; Lu, Yanhua

2015-01-01

More information regarding the bactericidal properties of polyhexamethylene guanidine hydrochloride (PHMG) against clinically important antibiotic-resistant ESKAPE (Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Enterobacter species) pathogens needs to be provided for its uses in infection control. The bactericidal properties of PHMG and chlorhexidine digluconate (CHG) were compared based on their minimum inhibitory concentrations (MICs), minimum bactericidal concentrations, and time-course-killing curves against clinically important antibiotic-susceptible and antibiotic-resistant ESKAPE pathogens. Results showed that PHMG exhibited significantly higher bactericidal activities against methicillin-resistant Staphylococcus aureus, carbapenem-resistant Klebsiella pneumoniae, and ceftazidime-resistant Enterobacter spp. than CHG. A slight bactericidal advantage over CHG was obtained against vancomycin-resistant Enterococcus faecium, ciprofloxacin- and levofloxacin-resistant Acinetobacter spp., and multidrug-resistant Pseudomonas aeruginosa. In previous reports, PHMG had higher antimicrobial activity against almost all tested Gram-negative bacteria and several Gram-positive bacteria than CHG using MIC test. These studies support the further development of covalently bound PHMG in sterile-surface materials and the incorporation of PHMG in novel disinfectant formulas. © 2014 International Union of Biochemistry and Molecular Biology, Inc.

[The importance of wildlife as reservoir of antibiotic-resistant bacteria in Bavaria--first results].

PubMed

Meyer, Cornelia; Heurich, Marco; Huber, Ingrid; Krause, Gladys; Ullrich, Ulrike; Fetsch, Alexandra

2014-01-01

The use of antimicrobial agents is responsible for the emergence and spread of antibiotic resistant bacteria. Nevertheless, multiresistant bacteria have been found in animals that have never been exposed to antimicrobial agents. Wild animals that are carriers of methicillin-resistant organisms represent a hazard since they can transmit their bacteria to other animals and to humans. In the hunting season 2009/2010 nasal swabs of 98 red deer and 109 wild boars were examined for the presence of methicillin-sensitive and methicillin-resistant staphylococci. From each wild boar methicillin-susceptible staphylococci (Staphylococcus aureus in 28% and Staphylococcus spp. in 72% of the animals) were isolated. In red deer the detection rate of Staphylococcus (S.) aureus and methicillin-susceptible staphylococci was 49% and 17%, respectively. The occurrence of S. aureus was significantly higher (p < 0.05) in red deer than in wild boars. Methicillin-resistant staphylococci were not found. However, in one third of the red deer, methicillin-resistant bacteria of the genus Enterococcus spp. and Bacillus spp. were isolated. The results of the present study indicate that wildlife, especially red deer are an important reservoir for S. aureus and that the upper respiratory tract of red deer is regularly colonised with methicillin-resistant bacteria such as Bacillus spp. and Enterococcus spp. Primarily, commensal bacteria are harmless to human health, however, red deer may be a reservoir for antibiotic-resistant bacteria.

Staphylococcus haemolyticus - an emerging threat in the twilight of the antibiotics age.

PubMed

Czekaj, Tomasz; Ciszewski, Marcin; Szewczyk, Eligia M

2015-11-01

Staphylococcus haemolyticus is one of the most frequent aetiological factors of staphylococcal infections. This species seems to lack the important virulence attributes described in other staphylococci. However, studies have shown that the presence of various enzymes, cytolysins and surface substances affects the virulence of S. haemolyticus. Nevertheless, none of them has been identified as crucial and determinative. Despite this, S. haemolyticus is, after Staphylococcus epidermidis, the second most frequently isolated coagulase-negative staphylococcus from clinical cases, notably from blood infections, including sepsis. This raises the question of what is the reason for the increasing clinical significance of S. haemolyticus? The most important factor might be the ability to acquire multiresistance against available antimicrobial agents, even glycopeptides. The unusual genome plasticity of S. haemolyticus strains manifested by a large number of insertion sequences and identified SNPs might contribute to its acquisition of antibiotic resistance. Interspecies transfer of SCCmec cassettes suggests that S. haemolyticus might also be the reservoir of resistance genes for other staphylococci, including Staphylococcus aureus. Taking into consideration the great adaptability and the ability to survive in the hospital environment, especially on medical devices, S. haemolyticus becomes a crucial factor in nosocomial infections caused by multiresistant staphylococci.

High Frequency and Diversity of Antimicrobial Activities Produced by Nasal Staphylococcus Strains against Bacterial Competitors

PubMed Central

Janek, Daniela; Zipperer, Alexander; Kulik, Andreas; Krismer, Bernhard; Peschel, Andreas

2016-01-01

The human nasal microbiota is highly variable and dynamic often enclosing major pathogens such as Staphylococcus aureus. The potential roles of bacteriocins or other mechanisms allowing certain bacterial clones to prevail in this nutrient-poor habitat have hardly been studied. Of 89 nasal Staphylococcus isolates, unexpectedly, the vast majority (84%) was found to produce antimicrobial substances in particular under habitat-specific stress conditions, such as iron limitation or exposure to hydrogen peroxide. Activity spectra were generally narrow but highly variable with activities against certain nasal members of the Actinobacteria, Proteobacteria, Firmicutes, or several groups of bacteria. Staphylococcus species and many other Firmicutes were insusceptible to most of the compounds. A representative bacteriocin was identified as a nukacin-related peptide whose inactivation reduced the capacity of the producer Staphylococcus epidermidis IVK45 to limit growth of other nasal bacteria. Of note, the bacteriocin genes were found on mobile genetic elements exhibiting signs of extensive horizontal gene transfer and rearrangements. Thus, continuously evolving bacteriocins appear to govern bacterial competition in the human nose and specific bacteriocins may become important agents for eradication of notorious opportunistic pathogens from human microbiota. PMID:27490492

The importance of staphylococci and threshold value of somatic cell count for diagnosis of sub-clinical mastitis in Pirlak sheep at mid-lactation.

PubMed

Ozenc, E; Seker, E; Baki Acar, D; Birdane, M K; Darbaz, I; Dogan, N

2011-12-01

This study investigated the bacterial agents causing sub-clinical mastitis and the mean somatic cell counts (SCC) of milk in Pirlak sheep at mid-lactation. The percentage of infected udder halves was 11.4% (53/464). The most frequently isolated species were coagulase-negative staphylococci (CNS) (64.2%), followed by Staphylococcus aureus (24.5%) and Escherichia coli (11.3%). Among the CNS, the most common species was Staphylococcus epidermidis (38.2%). The other species isolated from milk samples were Staphylococcus xylosus (17.7%), Staphylococcus chromogenes (14.7%), Staphylococcus simulans (8.8%) and Staphylococcus hyicus (8.8%). The mean SCC for culture positive and negative samples was 1742×10(3) and 161×10(3) cells/ml, respectively. A significant difference (p<0.05) was determined between with and without microbial growth groups in terms of the SCC values. Threshold limit for SCC was 374×10(3) cells/ml for Pirlak sheep. In conclusion, it was considered that SCC is an important predictor of sub-clinical mastitis in Pirlak sheep. This is the first study to describe the bacterial agents causing sub-clinical mastitis and threshold limit for SCC in Pirlak sheep in Turkey. © 2011 Blackwell Verlag GmbH.

Biological activity of common mullein, a medicinal plant.

PubMed

Turker, Arzu Ucar; Camper, N D

2002-10-01

Common Mullein (Verbascum thapsus L., Scrophulariaceae) is a medicinal plant that has been used for the treatment of inflammatory diseases, asthma, spasmodic coughs, diarrhea and other pulmonary problems. The objective of this study was to assess the biological activity of Common Mullein extracts and commercial Mullein products using selected bench top bioassays, including antibacterial, antitumor, and two toxicity assays--brine shrimp and radish seed. Extracts were prepared in water, ethanol and methanol. Antibacterial activity (especially the water extract) was observed with Klebsiella pneumonia, Staphylococcus aureus, Staphylococcus epidermidis and Escherichia coli. Agrobacterium tumefaciens-induced tumors in potato disc tissue were inhibited by all extracts. Toxicity to Brine Shrimp and to radish seed germination and growth was observed at higher concentrations of the extracts.

Phytosynthesis of Silver Nanoparticles Using Myrtus communis L. Leaf Extract and Investigation of Bactericidal Activity

NASA Astrophysics Data System (ADS)

Ajdari, M. R.; Tondro, G. H.; Sattarahmady, N.; Parsa, A.; Heli, H.

2017-12-01

Silver nanoparticles have been synthesized using only Myrtus communis L. leaf extract by a facile procedure without other reagents. The extract played the roles of both reducing and capping agent. The nanoparticles were characterized using field-emission scanning microscopy, and remained stable for at least 3 weeks. Antibacterial activity of the nanoparticles was evaluated toward Escherichia coli, Bacillus subtilis, Pseudomonas aeruginosa, Staphylococcus aureus, methicillin-resistant Staphylococcus aureus, and Enterococcus faecalis based on inhibition zone disk diffusion assays. The minimum inhibitory and bactericidal concentrations of the nanoparticles were obtained. Mechanisms for the antibacterial activity were proposed.

Prevalence of methicillin resistance and macrolide-lincosamide-streptogramin B resistance in Staphylococcus haemolyticus among clinical strains at a tertiary-care hospital in Thailand.

PubMed

Teeraputon, S; Santanirand, P; Wongchai, T; Songjang, W; Lapsomthob, N; Jaikrasun, D; Toonkaew, S; Tophon, P

2017-09-01

Staphylococcus spp. is a major cause of nosocomial infection and sepsis. However, increasing drug resistance is becoming a challenge to microbiologists. The purpose of this study was to identify and determine antimicrobial resistance phenotypes and drug resistance genes of clinical coagulase-negative staphylococci (CoNS) isolates at Mae Sot Hospital in Tak province, Thailand. A total of 229 CoNS isolates were collected from clinical specimens during two periods in 2014 and in 2015. Staphylococcus haemolyticus was the most prevalent species (37.55%), followed by S. epidermidis (21.83%), S. saprophyticus (11.79%) and S. hominis (11.35%) respectively. The remaining 17.48% of the organisms comprised S. capitis, S. arlettae, S. cohnii, S. equorum, S. xylosus, S. warneri, S. sciuri, S. pettenkoferi, S. kloosii and S. lugdunensis. Methicillin-resistant CoNS (MRCoNS), containing the mec A gene, were detected in 145 of 229 isolates, mostly found in S. haemolyticus and S. epidermidis. In addition, the differentiation of their macrolide-lincosamide-streptogramin B (MLS B ) resistance phenotypes was determined by the D-test and corresponding resistance genes. Among 125 erythromycin-resistant CoNS, the prevalence of constitutive type of MLS B , inducible clindamycin resistance and macrolide-streptogramin B resistance phenotypes were 72, 13.60 and 14.40% respectively. These phenotypes were expressed in 80% of MRCoNS strains. In addition, the erm C gene (79.20%) was found to be more prevalent than the erm A gene (22.40%), especially among MRCoNS. These results indicate that CoNS may play an important role in spreading of drug resistance genes. More attention to these organisms in surveillance and monitoring programs is needed.

Prevalence of Staphylococcus spp. nasal colonization among doctors of podiatric medicine and associated risk factors in Spain.

PubMed

de Benito, Sheila; Alou, Luis; Becerro-de-Bengoa-Vallejo, Ricardo; Losa-Iglesias, Marta Elena; Gómez-Lus, María Luisa; Collado, Luis; Sevillano, David

2018-01-01

This study aimed to estimate the prevalence of methicillin-susceptible and -resistant Staphylococcus aureus (MSSA and MRSA) and methicillin-resistant Staphylococcus epidermidis (MRSE) nasopharyngeal carriage among Doctors of Podiatric Medicine (Podiatrists) and to determine the potential risk factors. A cross-sectional study was carried out in 2016-2017 among 239 podiatrists in Spain. The presence of MSSA, MRSA, and MRSE was determined by microbiological analysis of nasal exudate and antimicrobial susceptibility was determined. Each podiatrist completed a questionnaire. The questionnaire comprised various parameters such as sex, age, podiatry experience duration, underlying diseases, prior antibiotic treatment, hospitalization during the last year, and use of a protective mask, an aspiration system, or gloves. The prevalence of MSSA, MRSA, and MRSE was 23.0%, 1.3%, and 23.8%, respectively. The MSSA prevalence was higher among podiatrists who did not use an aspiration system (32.3%) compared to those who did (19.3%; p  = 0.0305), and among podiatrists with respiratory diseases (36.8%) compared to those without (20.8%; p  = 0.0272). The MRSE prevalence was higher among men (33.7%) compared to women (8.6%; p  = 0.0089), podiatrists aged ≥50 (38.5%) compared to ≤35 (17.8%; p  = 0.0101), and podiatrists with ≥15 (39.3%) compared to ≤5 years of podiatry experience (12.5%; p  = 0.0015). Among the S. aureus strains, 84.5% were resistant to penicillin, 22.4% to erythromycin, 20.7% to clindamycin, and 12.7% to mupirocin. The MRSE strains were resistant to penicillin (93.0%), erythromycin (78.9%), and mupirocin (73.7%). The prevalence of S. aureus and S. epidermidis nasal carriage is low among Spanish podiatrists compared to other health professionals.

Traditional medicine in Sakarya province (Turkey) and antimicrobial activities of selected species.

PubMed

Uzun, Ergin; Sariyar, Günay; Adsersen, Anne; Karakoc, Berna; Otük, Gülten; Oktayoglu, Ercan; Pirildar, Sevda

2004-12-01

Traditional medicine in North-West of Turkey (Sakarya province) were studied during a 2 months field study by interviewing local informants from several villages. Plant species used to treat infections were tested for antimicrobial activity. Information was collected for 46 plant species from 30 families and for 5 animal species. Twenty four of the plant species were cultivated. Most used families were Asteraceae, Cucurbitaceae, Lamiaceae and Rosaceae and the most used plants were Artemisia absinthium, Equisetum telmateia, Lavandula stoechas, Melissa officinalis, Tussilago farfara and Urtica dioica. A total of 139 medicinal uses were obtained. Plants are used mainly for infectious diseases (18%), for neurological and psychological disorders (13.7%), cardiovascular disorders (13%), skin disorders (12.2%) and respiratory disorders (10.1%). Extracts were tested in vitro for antimicrobial activity against Staphylococcus aureus ATCC 65538, Staphylococcus epidermidis ATCC 12228, Escherichia coli ATCC 8739, Klebsiella pneumonia ATCC 4352, Pseudomonas aeruginosa ATCC 1539, Salmonella typhi, Shigella flexneri, Proteus mirabilis and Candida albicans ATCC 10231, using microbroth dilution technique according to National Committee for Clinical Laboratory Standards (NCCLS). This research showed that Arum maculatum, Datura stramonium, Geranium asphodeloides and Equisetum telmateia petroleum ether extracts had MIC values of 39.1 microg/ml, 78.1 microg/ml, 78.1 microg/ml and 39.1 microg/ml, respectively against Staphylococcus epidermidis. Datura stramonium petroleum ether extract had a MIC value of 39.1 microg/ml against Escherichia coli and Trachystemon orientalis ethanol extract had a MIC value of 39.1 microg/ml against Escherichia coli. The antimicrobial activity of Arum maculatum, Equisetum telmateia, Geranium asphodeloides, Plantago intermedia, Senecio vulgaris and Trachystemon orientalis has been reported here for the first time.