scholarly journals Cold Atmospheric Air Plasma Sterilization against Spores and Other Microorganisms of Clinical Interest

2012 ◽  
Vol 78 (15) ◽  
pp. 5077-5082 ◽  
Author(s):  
Tobias G. Klämpfl ◽  
Georg Isbary ◽  
Tetsuji Shimizu ◽  
Yang-Fang Li ◽  
Julia L. Zimmermann ◽  
...  
Keyword(s):  
Ambient Air ◽  
Health Care Facilities ◽  
Diagnostic Methods ◽  
Air Plasma ◽  
Content Type ◽  
Gram Positive Bacteria ◽  
Bacterial Endospores ◽  
Reactive Plasma ◽  
Plasma Species ◽  
Clinical Interest

ABSTRACTPhysical cold atmospheric surface microdischarge (SMD) plasma operating in ambient air has promising properties for the sterilization of sensitive medical devices where conventional methods are not applicable. Furthermore, SMD plasma could revolutionize the field of disinfection at health care facilities. The antimicrobial effects on Gram-negative and Gram-positive bacteria of clinical relevance, as well as the fungusCandida albicans, were tested. Thirty seconds of plasma treatment led to a 4 to 6 log10CFU reduction on agar plates.C. albicanswas the hardest to inactivate. The sterilizing effect on standard bioindicators (bacterial endospores) was evaluated on dry test specimens that were wrapped in Tyvek coupons. The experimentalD23°Cvalues forBacillus subtilis,Bacillus pumilus,Bacillus atrophaeus, andGeobacillus stearothermophiluswere determined as 0.3 min, 0.5 min, 0.6 min, and 0.9 min, respectively. These decimal reduction times (Dvalues) are distinctly lower thanDvalues obtained with other reference methods. Importantly, the high inactivation rate was independent of the material of the test specimen. Possible inactivation mechanisms for relevant microorganisms are briefly discussed, emphasizing the important role of neutral reactive plasma species and pointing to recent diagnostic methods that will contribute to a better understanding of the strong biocidal effect of SMD air plasma.

scholarly journals Analysis of a Candida auris Outbreak Provides New Insights into an Emerging Pathogen

2020 ◽  
Vol 58 (4) ◽  
Author(s):  
Brian L. Wickes
Keyword(s):  
Health Care ◽  
New York ◽  
Fungal Pathogen ◽  
Antifungal Susceptibility ◽  
Health Care Facilities ◽  
Diagnostic Methods ◽  
Candida Auris ◽  
Laboratory Findings ◽  
Content Type ◽  
Human Fungal Pathogen

ABSTRACT Candida auris is an emerging human fungal pathogen that is being increasingly linked to outbreaks. It is concerning to health care workers because of its high mortality rate, due primarily to its antifungal resistance. Among the tools being developed to study this yeast are large cohorts of regional isolates, which can be useful for studying epidemiology, antifungal susceptibility patterns, and diagnostic methods. In this issue of the Journal of Clinical Microbiology, Y. Zhu, B. O’Brien, L. Leach, A. Clarke, et al. (J Clin Microbiol 58:e01503-19, 2020, https://doi.org/10.1128/JCM.01503-19) describe the laboratory findings of a collection of isolates from a large outbreak of C. auris obtained from numerous health care facilities in the New York area. Real-time PCR was used as a screening tool with great accuracy, while internal transcribed spacer (ITS) and D1/D2 sequencing were successfully employed for isolate clade assignment. South Asia clade I was identified as the major genotype, while South American clade IV was a minor genotype. Surveillance isolates from patients confirmed axilla/groin and nare colonization; however, results of quantitative analysis of fungal burdens showed that when the nares are colonized, burdens are significantly higher than for axilla/groin colonization. Antifungal susceptibility testing was in agreement with past studies. High levels of fluconazole resistance were detected, while few isolates were resistant to echinocandins. Resistance to multiple antifungals was frequent, and three isolates were recovered that appeared to be pan-resistant. This type of study is yet another useful tool for investigating C. auris, which is becoming an increasingly important human fungal pathogen that should be monitored very closely.

Patient satisfaction with the quality of care in Ghana’s health-care institutions

2019 ◽  
Vol 13 (2) ◽  
pp. 160-170 ◽  
Author(s):  
Aaron Asibi Abuosi ◽  
Mahama Braimah
Keyword(s):  
Health Care ◽  
Patient Satisfaction ◽  
Quality Of Care ◽  
Service Delivery ◽  
National Survey ◽  
Health Care Facilities ◽  
Health Facilities ◽  
Content Type ◽  
Care Facilities

Purpose The purpose of this study was to examine patient satisfaction with the quality of care in Ghana’s health-care facilities using a disaggregated approach. Design/methodology/approach The study was a cross-sectional national survey. A sample of 4,079 males and females in the age group of 15-49 years were interviewed. Descriptive statistics, principal component analysis and t-tests were used in statistical analysis. Findings About 70 per cent of patients were satisfied with the quality of care provided in health-care facilities in Ghana, whereas about 30 per cent of patients were fairly satisfied. Females and insured patients were more likely to be satisfied with the quality of care, compared with males and uninsured patients. Research limitations/implications Because data were obtained from a national survey, the questionnaire did not include the type of facility patients attended to find out whether satisfaction with the quality of care varied by the type of health facility. Future studies may, therefore, include this. Practical implications The study contributes to the literature on patient satisfaction with the quality of care. It highlights that long waiting time remains an intractable problem at various service delivery units of health facilities and constitutes a major source of patient dissatisfaction with the quality of care. Innovative measures must, therefore, be adopted to address the problem. Originality/value There is a paucity of research that uses a disaggregated approach to examine patient satisfaction with the quality of care at various service delivery units of health facilities. This study is a modest contribution to this research gap.

scholarly journals CodY Is a Global Regulator of Virulence-Associated Properties for Clostridium perfringens Type D Strain CN3718

mBio ◽  
2013 ◽  
Vol 4 (5) ◽  
Author(s):  
Jihong Li ◽  
Menglin Ma ◽  
Mahfuzur R. Sarker ◽  
Bruce A. McClane
Keyword(s):  
Clostridium Perfringens ◽  
Null Mutant ◽  
Intestinal Infection ◽  
Wild Type ◽  
Global Regulator ◽  
Content Type ◽  
Gram Positive Bacteria ◽  
Type D ◽  
Epsilon Toxin ◽  
Virulence Properties

ABSTRACT CodY is known to regulate various virulence properties in several Gram-positive bacteria but has not yet been studied in the important histotoxic and intestinal pathogen Clostridium perfringens. The present study prepared an isogenic codY-null mutant in C. perfringens type D strain CN3718 by insertional mutagenesis using the Targetron system. Western blot analysis indicated that, relative to wild-type CN3718 or a complementing strain, this isogenic codY mutant produces reduced levels of epsilon toxin (ETX). Using supernatants from cultures of the wild-type, codY-null mutant, and complementing strains, CodY regulation of ETX production was shown to have cytotoxic consequences for MDCK cells. The CodY regulatory effect on ETX production was specific, since the codY-null mutant still made wild-type levels of alpha-toxin and perfringolysin O. Sialidase activity measurements and sialidase Western blot analysis of supernatants from CN3718 and its isogenic derivatives showed that CodY represses overall exosialidase activity due to a reduced presence of NanH in culture supernatants. Inactivation of the codY gene significantly decreased the adherence of CN3718 vegetative cells or spores to host Caco-2 cells. Finally, the codY mutant showed increased spore formation under vegetative growth conditions, although germination of these spores was impaired. Overall, these results identify CodY as a global regulator of many C. perfringens virulence-associated properties. Furthermore, they establish that, via CodY, CN3718 coordinately regulates many virulence-associated properties likely needed for intestinal infection. IMPORTANCE Clostridium perfringens is a major human and livestock pathogen because it produces many potent toxins. C. perfringens type D strains cause intestinal infections by producing toxins, especially epsilon toxin (ETX). Previous studies identified CodY as a regulator of certain virulence properties in other Gram-positive bacteria. Our study now demonstrates that CodY is a global regulator of virulence-associated properties for type D strain CN3718. It promotes production of ETX, attachment of CN3718 vegetative cells or spores to host enterocyte-like Caco-2 cells, and spore germination; the last two effects may assist intestinal colonization. In contrast, CodY represses sporulation. These results provide the first evidence that CodY can function as a global regulator of C. perfringens virulence-associated properties and that this strain coordinately regulates its virulence-associated properties using CodY to increase ETX production, host cell attachment, and spore germination but to repress sporulation, as would be optimal during type D intestinal infection.

scholarly journals Infection with Toxin A-Negative, Toxin B-Negative, Binary Toxin-Positive Clostridium difficile in a Young Patient with Ulcerative Colitis

2015 ◽  
Vol 53 (11) ◽  
pp. 3702-3704 ◽  
Author(s):  
Grace O. Androga ◽  
Julie Hart ◽  
Niki F. Foster ◽  
Adrian Charles ◽  
David Forbes ◽  
...  
Keyword(s):  
Ulcerative Colitis ◽  
Clostridium Difficile ◽  
Young Patient ◽  
Diagnostic Methods ◽  
Binary Toxin ◽  
Toxin A ◽  
Toxin B ◽  
Content Type ◽  
Severe Diarrhea ◽  
Clinically Significant

Large clostridial toxin-negative, binary toxin-positive (A−B−CDT+) strains ofClostridium difficileare almost never associated with clinically significantC. difficileinfection (CDI), possibly because such strains are not detected by most diagnostic methods. We report the isolation of an A−B−CDT+ribotype 033 (RT033) strain ofC. difficilefrom a young patient with ulcerative colitis and severe diarrhea.

scholarly journals Antimicrobial Nodule-Specific Cysteine-Rich Peptides Induce Membrane Depolarization-Associated Changes in the Transcriptome of Sinorhizobium meliloti

2013 ◽  
Vol 79 (21) ◽  
pp. 6737-6746 ◽  
Author(s):  
Hilda Tiricz ◽  
Attila Szűcs ◽  
Attila Farkas ◽  
Bernadett Pap ◽  
Rui M. Lima ◽  
...  
Keyword(s):  
Stress Responses ◽  
Sinorhizobium Meliloti ◽  
Antimicrobial Agents ◽  
Cellular Functions ◽  
Gram Positive ◽  
Content Type ◽  
Gram Positive Bacteria ◽  
Peptide Family ◽  
Wide Range ◽  
Natural Target

ABSTRACTLeguminous plants establish symbiosis with nitrogen-fixing alpha- and betaproteobacteria, collectively called rhizobia, which provide combined nitrogen to support plant growth. Members of the inverted repeat-lacking clade of legumes impose terminal differentiation on their endosymbiotic bacterium partners with the help of the nodule-specific cysteine-rich (NCR) peptide family composed of close to 600 members. Among the few tested NCR peptides, cationic ones had antirhizobial activity measured by reduction or elimination of the CFU and uptake of the membrane-impermeable dye propidium iodide. Here, the antimicrobial spectrum of two of these peptides, NCR247 and NCR335, was investigated, and their effect on the transcriptome of the natural targetSinorhizobium melilotiwas characterized. Both peptides were able to kill quickly a wide range of Gram-negative and Gram-positive bacteria; however, their spectra were only partially overlapping, and differences were found also in their efficacy on given strains, indicating that the actions of NCR247 and NCR335 might be similar though not identical. Treatment ofS. meliloticultures with either peptide resulted in a quick downregulation of genes involved in basic cellular functions, such as transcription-translation and energy production, as well as upregulation of genes involved in stress and oxidative stress responses and membrane transport. Similar changes provoked mainly in Gram-positive bacteria by antimicrobial agents were coupled with the destruction of membrane potential, indicating that it might also be a common step in the bactericidal actions of NCR247 and NCR335.

scholarly journals Antimicrobial Properties of 8-Hydroxyserrulat-14-en-19-oic Acid for Treatment of Implant-Associated Infections

2012 ◽  
Vol 57 (1) ◽  
pp. 333-342 ◽  
Author(s):  
Justyna Nowakowska ◽  
Hans J. Griesser ◽  
Marcus Textor ◽  
Regine Landmann ◽  
Nina Khanna
Keyword(s):  
Structural Changes ◽  
Treatment Options ◽  
Antimicrobial Properties ◽  
Bactericidal Effect ◽  
Mouse Tissue ◽  
Logarithmic Phase ◽  
Content Type ◽  
Gram Positive Bacteria ◽  
Time Kill

ABSTRACTTreatment options are limited for implant-associated infections (IAI) that are mainly caused by biofilm-forming staphylococci. We report here on the activity of the serrulatane compound 8-hydroxyserrulat-14-en-19-oic acid (EN4), a diterpene isolated from the Australian plantEremophila neglecta. EN4 elicited antimicrobial activity toward various Gram-positive bacteria but not to Gram-negative bacteria. It showed a similar bactericidal effect against logarithmic-phase, stationary-phase, and adherentStaphylococcus epidermidis, as well as against methicillin-susceptible and methicillin-resistantS. aureuswith MICs of 25 to 50 μg/ml and MBCs of 50 to 100 μg/ml. The bactericidal activity of EN4 was similar againstS. epidermidisand its Δicamutant, which is unable to produce polysaccharide intercellular adhesin-mediated biofilm. In time-kill studies, EN4 exhibited a rapid and concentration-dependent killing of staphylococci, reducing bacterial counts by >3 log10CFU/ml within 5 min at concentrations of >50 μg/ml. Investigation of the mode of action of EN4 revealed membranolytic properties and a general inhibition of macromolecular biosynthesis, suggesting a multitarget activity.In vitro-tested cytotoxicity on eukaryotic cells was time and concentration dependent in the range of the MBCs. EN4 was then tested in a mouse tissue cage model, where it showed neither bactericidal nor cytotoxic effects, indicating an inhibition of its activity. Inhibition assays revealed that this was caused by interactions with albumin. Overall, these findings suggest that, upon structural changes, EN4 might be a promising pharmacophore for the development of new antimicrobials to treat IAI.

scholarly journals Restoration of Bioactive Lantibiotic Suicin from a RemnantlanLocus of Pathogenic Streptococcus suis Serotype 2

2013 ◽  
Vol 80 (3) ◽  
pp. 1062-1071 ◽  
Author(s):  
Jian Wang ◽  
Yong Gao ◽  
Kunling Teng ◽  
Jie Zhang ◽  
Shutao Sun ◽  
...  
Keyword(s):  
Gene Promoter ◽  
Streptococcus Suis ◽  
Gene Clusters ◽  
Disulfide Bridge ◽  
Gram Positive ◽  
Content Type ◽  
Gram Positive Bacteria ◽  
System A ◽  
Bactericidal Activities

ABSTRACTLantibiotics are ribosomally synthesized, posttranslationally modified antimicrobial peptides. Their biosynthesis genes are usually organized in gene clusters, which are mainly found in Gram-positive bacteria, including pathogenic streptococci. Three highly virulentStreptococcus suisserotype 2 strains (98HAH33, 05ZYH33, and SC84) have been shown to contain an 89K pathogenicity island. Here, on these islands, we unveiled and reannotated a putative lantibiotic locus designatedsuiwhich contains a virulence-associated two-component regulator,suiK-suiR. In silicoanalysis revealed that the putative lantibiotic modification genesuiMwas interrupted by a 7.9-kb integron and that other biosynthesis-related genes contained various frameshift mutations. By reconstituting the intactsuiMinEscherichia colitogether with a semi-in vitrobiosynthesis system, a putative lantibiotic named suicin was produced with bactericidal activities against a variety of Gram-positive strains, including pathogenic streptococci and vancomycin-resistant enterococci. Ring topology dissection indicated that the 34-amino-acid lantibiotic contained two methyllanthionine residues and one disulfide bridge, which render suicin in an N-terminal linear and C-terminal globular shape. To confirm the function ofsuiK-suiR, SuiR was overexpressed and purified.In vitroanalysis showed that SuiR could specifically bind to thesuiAgene promoter. Its coexpression withsuiKcould activatesuiAgene promoter inLactococcus lactisNZ9000. Conclusively, we obtained a novel lantibiotic suicin by restoring its production from the remnantsuilocus and demonstrated that virulence-associated SuiK-SuiR regulates its production.

Evaluation of the influence of ambient air temperature and air velocity on mortar cement durability using a forced convection solar dryer

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Younes Bahammou ◽  
Mounir Kouhila ◽  
Haytem Moussaoui ◽  
Hamza Lamsyehe ◽  
Zakaria Tagnamas ◽  
...  
Keyword(s):  
Environmental Factors ◽  
Forced Convection ◽  
Air Temperature ◽  
Building Materials ◽  
Ambient Air ◽  
Physical Significance ◽  
Drying Process ◽  
Air Velocity ◽  
Content Type ◽  
Ambient Air Temperature

PurposeThis work aims to study the hydrothermal behavior of mortar cement toward certain environmental factors (ambient air temperature and air velocity) based on its drying kinetics data. The objective is to provide a better understanding and controlling the stability of mortar structures, which integrate the sorption phenomenon, drying process, air pressure and intrinsic characteristics. This leads to predict the comportment of mortar structures in relation with main environmental factors and minimize the risk of cracking mortar structures at an early age.Design/methodology/approachThermokinetic study was carried out in natural and forced convection solar drying at three temperatures 20, 30 and 40°C and three air velocities (1, 3 and 5 m.s-1). The empirical and semiempirical models tested successfully describe the drying kinetics of mortar. These models simulate the drying process of water absorbed by capillarity, which is the most common humidity transfer mechanism in building materials and contain parameters with physical significance, which integrate the effect of several environmental factors and intrinsic characteristics of mortar structures.FindingsThe models simulate the drying process of water absorbed by capillarity, which is the most common humidity transfer mechanism in building materials and contain parameters with physical significance, which integrate the effect of several environmental factors and intrinsic characteristics of mortar structures. The average activation energy obtained expressed the temperature effect on the mortar diffusivity. The drying constant and the diffusion coefficient can be used to predict the influence of these environmental factors on the drying behavior of various building materials and therefore on their durability.Originality/valueEvaluation of the effect of several environmental factors and intrinsic characteristics of mortar structures on their durability.

Adaptation of gltA and ssrA assays for diversity profiling by Illumina sequencing to identify Bartonella henselae, B. clarridgeiae and B. koehlerae

2021 ◽  
Vol 70 (7) ◽  
Author(s):  
Rosemonde Isabella Power ◽  
Nichola Elisa Davies Calvani ◽  
Yaarit Nachum-Biala ◽  
Harold Salant ◽  
Shimon Harrus ◽  
...  
Keyword(s):  
Illumina Sequencing ◽  
Type Species ◽  
Bacterial Infections ◽  
Sanger Sequencing ◽  
Bartonella Henselae ◽  
Diagnostic Methods ◽  
Mixed Infections ◽  
Accurate Identification ◽  
Content Type ◽  
Link Type

Introduction. Bartonellosis is an emerging zoonotic disease caused by bacteria of the genus Bartonella . Mixed Bartonella infections are a well-documented phenomenon in mammals and their ectoparasites. The accurate identification of Bartonella species in single and mixed infections is valuable, as different Bartonella species have varying impacts on infected hosts. Gap Statement. Current diagnostic methods are inadequate at identifying the Bartonella species present in mixed infections. Aim. The aim of this study was to adopt a Next Generation Sequencing (NGS) approach using Illumina sequencing technology to identify Bartonella species and demonstrate that this approach can resolve mixed Bartonella infections. Methodology. We used Illumina PCR amplicon NGS to target the ssrA and gltA genes of Bartonella in fleas collected from cats, dogs and a hedgehog in Israel. We included artificially mixed Bartonella samples to demonstrate the ability for NGS to resolve mixed infections and we compared NGS to traditional Sanger sequencing. Results. In total, we identified 74 Ctenocephalides felis, two Ctenocephalides canis, two Pulex irritans and three Archaeopsylla e. erinacei fleas. Real-time PCR of a subset of 48 fleas revealed that twelve were positive for Bartonella , all of which were cat fleas. Sanger sequencing of the ssrA and gltA genes confirmed the presence of Bartonella henselae , Bartonella clarridgeiae and Bartonella koehlerae . Illumina NGS of ssrA and gltA amplicons further confirmed the Bartonella species identity in all 12 flea samples and unambiguously resolved the artificially mixed Bartonella samples. Conclusion. The adaptation and multiplexing of existing PCR assays for diversity profiling via NGS is a feasible approach that is superior to traditional Sanger sequencing for Bartonella speciation and resolving mixed Bartonella infections. The adaptation of other PCR primers for Illumina NGS will be useful in future studies where mixed bacterial infections may be present.

scholarly journals Antibacterial activity of Baccharis trimera (Less.) DC. (carqueja) against bacteria of medical interest

Revista CERES ◽  
2013 ◽  
Vol 60 (5) ◽  
pp. 731-734 ◽  
Author(s):  
Álan Alex Aleixo ◽  
Karina Marjorie Silva Herrera ◽  
Rosy Iara Maciel de Azambuja Ribeiro ◽  
Luciana Alves Rodrigues dos Santos Lima ◽  
Jaqueline Maria Siqueira Ferreira
Keyword(s):  
Antibacterial Activity ◽  
Folk Medicine ◽  
Salmonella Typhi ◽  
Bacterial Strains ◽  
Gram Positive ◽  
Gram Positive Bacteria ◽  
Clinical Interest ◽  
Antibacterial Susceptibility ◽  
Baccharis Trimera ◽  
Medical Interest

Baccharis trimera (Less.) (Asteraceae), popularly know as "carqueja", is a species commonly used in folk medicine for the treatment or prevention of diseases. In this context, the purpose of this work was to study the antibacterial activity of crude hydroalcoholic extract from Baccharis trimera against Gram-positive bacterial strains (Staphylococcus aureus ATCC 29213, Staphylococcus saprophyticus ATCC 15305, Staphylococcus epidermidis ATCC 12228, Enterococcus faecalis ATCC 19433) and Gram-negative bacteria (Escherichia coli EHEC ATCC 43895, Pseudomonas aeruginosa ATCC 27853, Klebsiella pneumoniae ATCC 27736, Salmonella typhi ATCC 19430) of clinical interest. Antibacterial susceptibility was evaluated by broth microdilution assay following the CLSI (formerly the NCCLS) guidelines. The extract from B. trimera showed antibacterial activity against Gram-positive bacteria and the most interesting result was obtained against S. epidermidis that presented Minimal Inhibitory Concentration of 250μg/mL. These results indicate that B. trimera have bacterisostatic potential against Gram-positive bacterial strains of medical interest and could serve as a base for further studies on the use of isolated compounds from this species as future antimicrobials.

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