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1.
mSphere ; 4(5)2019 09 04.
Artigo em Inglês | MEDLINE | ID: mdl-31484739

RESUMO

Urgency urinary incontinence (UUI) and overactive bladder (OAB) can both potentially be influenced by commensal and urinary tract infection-associated bacteria. The sensing of bladder filling involves interplay between various components of the nervous system, eventually resulting in contraction of the detrusor muscle during micturition. This study models host responses to various urogenital bacteria, first by using urothelial bladder cell lines and then with myofibroblast contraction assays. To measure responses, we examined Ca2+ influx, gene expression, and alpha smooth muscle actin deposition assays. Organisms such as Escherichia coli and Gardnerella vaginalis were found to strongly induce Ca2+ influx and contraction, whereas Lactobacillus crispatus and L. gasseri did not induce this response. Additionally, supernatants from lactobacilli impeded Ca2+ influx and contraction induced by uropathogens. Upon further investigation of factors associated with purinergic signaling pathways, the Ca2+ influx and contraction of cells correlated with the amount of extracellular ATP produced by E. coli Certain lactobacilli appear to mitigate this response by utilizing extracellular ATP or producing inhibitory compounds that may act as a receptor agonist or Ca2+ channel blocker. These findings suggest that members of the urinary microbiota may be influencing UUI or OAB.IMPORTANCE The ability of uropathogenic bacteria to release excitatory compounds, such as ATP, may act as a virulence factor to stimulate signaling pathways that could have profound effects on the urothelium, perhaps extending to the vagina. This may be countered by the ability of certain commensal urinary microbiota constituents, such as lactobacilli. Further understanding of these interactions is important for the treatment and prevention of UUI and OAB. The clinical implications may require a more targeted approach to enhance the commensal bacteria and reduce ATP release by pathogens.


Assuntos
Trifosfato de Adenosina/metabolismo , Bactérias/metabolismo , Cálcio/metabolismo , Miofibroblastos/citologia , Bexiga Urinária/microbiologia , Actinas/fisiologia , Bactérias/patogenicidade , Linhagem Celular , Colágeno/fisiologia , Humanos , Lactobacillales , Microbiota , Contração Muscular , Miofibroblastos/microbiologia , Simbiose , Bexiga Urinária/fisiologia , Urotélio/citologia
2.
Genome Announc ; 5(27)2017 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-28684574

RESUMO

Here, we present the draft genome sequence of Escherichia coli ATCC 10798. E. coli ATCC 10798 is a K-12 strain, one of the most well-studied model microorganisms. The size of the genome was 4,685,496 bp, with a G+C content of 50.70%. This assembly consists of 62 contigs and the F plasmid.

3.
Genome Announc ; 5(27)2017 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-28684575

RESUMO

A draft genome sequence for Escherichia coli ATCC 29425 was investigated. The size of the genome was 4,608,319 bp, with an observed G+C content of 50.68%. This assembly consisted of 80 contigs, with an average coverage of 122.2×, including one contig representative of the complete genome for the temperate phage P1.

4.
Genome Announc ; 5(27)2017 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-28684577

RESUMO

The actinobacterium Micrococcus luteus can be found in a wide variety of habitats. Here, we report the 2,411,958-bp draft genome sequence of the type strain M. leuteus (Schroeter) Cohn (ATCC 12698). Characteristic of this taxa, the genome sequence has a high G+C content, 73.14%.

5.
Genome Announc ; 5(27)2017 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-28684576

RESUMO

While a part of the native gut microflora, the Gram-positive bacterium Enterococcus faecalis can lead to serious infections elsewhere in the body. The draft genome of E. faecalis strain ATCC BAA-2128, isolated from piglet feces, was examined. This draft genome consists of 42 contigs, 12 of which exhibit homology to annotated plasmids.

6.
Genome Announc ; 5(27)2017 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-28684583

RESUMO

Draft genome sequences for Staphylococcus aureus subsp. aureus Rosenbach ATCC 14458 and ATCC 27217 strains were investigated. The genome sizes were 2,880,761 bp and 2,759,100 bp, respectively. Strain ATCC 14458 was assembled into 39 contigs, including 3 plasmids, and strain ATCC 27217 was assembled into 25 contigs, including 2 plasmids.

7.
Genome Announc ; 5(27)2017 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-28684584

RESUMO

Here, we report the draft genome sequence for the type strain Staphylococcus epidermidis (Winslow and Winslow) Evans (ATCC 14990). The assembly consisted of 2,457,519 bp with an observed G+C content of 32.04%. Thirty-seven contigs were produced, including two putative plasmids, with a 296.8× coverage and an N50 of 180,848 bp.

8.
Future Med Chem ; 8(10): 1101-10, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27284624

RESUMO

Host-defense peptides (HDPs) are promising next generation of antibiotic agents, as they have the potential to circumvent emerging drug resistance, due to their mechanism of bacterial killing through disruption of their membranes. Nonetheless, HDPs have intrinsic drawbacks such as low-to-moderate activity, susceptibility to enzymatic degradation. In the past few years, we developed a new class of peptidomimetics named 'γ-AApeptides', which have superior resistance to proteolysis and a variety of diversification via straightforward synthesis. Our recent studies suggested that γ-AApeptides can mimic the bactericidal mechanism of HDPs and show potent and broad-spectrum activity against both Gram-positive and Gram-negative multidrug-resistant bacteria. In this review, we summarize our current studies of antimicrobial γ-AApeptides and discuss their potential future development as antimicrobial peptidomimetics.


Assuntos
Antibacterianos/química , Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Descoberta de Drogas , Peptídeos/química , Peptídeos/farmacologia , Peptídeos Catiônicos Antimicrobianos/química , Peptídeos Catiônicos Antimicrobianos/farmacologia , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Mimetismo Molecular
10.
Am J Infect Control ; 44(2): 245-6, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26549663

RESUMO

This report describes fomite transmission of Staphylococcus aureus amongst various surfaces. A contact transfer protocol was completed to evaluate the movement of S aureus between a person wearing nitrile gloves and either: handshaking with another person with gloved hands, touching a plastic cellular telephone back, or touching a stainless steel rod. The data in this preliminary study imply that the highest bacterial transfer is with metal surfaces followed by plastic. Interestingly, glove-to-glove transfer occurred but transfered less bacteria than a plastic or metal surface. The observations from this study point to the need to clearly define hygiene behaviors to reduce the potential of hand- and surface-mediated transmission.


Assuntos
Luvas Protetoras/microbiologia , Mãos/microbiologia , Infecções Estafilocócicas/transmissão , Staphylococcus aureus/fisiologia , Telefone Celular , Fômites/microbiologia , Higiene das Mãos , Humanos , Nitrilas , Plásticos , Aço Inoxidável , Infecções Estafilocócicas/microbiologia
11.
Arch Environ Occup Health ; 71(3): 157-62, 2016 05 03.
Artigo em Inglês | MEDLINE | ID: mdl-26066784

RESUMO

Viral illnesses such as gastroenteritis and the common cold create a substantial burden in the workplace due to reduced productivity, increased absenteeism, and increased health care costs. Behaviors in the workplace contribute to the spread of human viruses via direct contact between hands, contaminated surfaces, and the mouth, eyes, and/or nose. This study assessed whether implementation of the Healthy Workplace Project (HWP) (providing hand sanitizers, disinfecting wipes, facial tissues, and use instructions) would reduce viral loads in an office setting of approximately 80 employees after seeding fomites and the hands of volunteer participants with an MS-2 phage tracer. The HWP significantly reduced viable phage detected on participants' hands, communal fomites, and personal fomites (p ≤ .010) in office environments and presents a cost-effective method for reducing the health and economic burden associated with viral illnesses in the workplace.


Assuntos
Promoção da Saúde/métodos , Exposição Ocupacional/prevenção & controle , Viroses/prevenção & controle , Local de Trabalho , Contaminação de Equipamentos , Humanos , Vírus/isolamento & purificação
12.
Am J Infect Control ; 43(7): 702-6, 2015 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-25944726

RESUMO

BACKGROUND: Approximately 50% of norovirus cases in the United States occur in long-term care facilities; many incidences of rotavirus, sapovirus, and adenovirus also occur. The primary objectives of this study were to demonstrate movement of pathogenic viruses through a long-term care facility and to determine the impact of a hygiene intervention on viral transmission. METHODS: The coliphage MS-2 was seeded onto a staff member's hands, and samples were collected after 4 hours from fomites and hands. After 3 consecutive days of sample collection, a 14-day hygiene intervention was implemented. Hand sanitizers, hand and face wipes, antiviral tissues, and a disinfectant spray were distributed to employees and residents. Seeding and sampling were repeated postintervention. RESULTS: Analysis of the pre- and postintervention data was performed using a Wilcoxon signed-rank test. Significant reductions in the spread of MS-2 on hands (P = .0002) and fomites (P = .04) were observed postintervention, with a >99% average reduction of virus recovered from both hands and fomites. CONCLUSION: Although MS-2 spread readily from hands to fomites and vice versa, the intervention reduced average MS-2 concentrations recovered from hands and fomites by up to 4 logs and also reduced the incidence of MS-2 recovery.


Assuntos
Infecção Hospitalar/prevenção & controle , Transmissão de Doença Infecciosa/prevenção & controle , Higiene das Mãos/métodos , Instalações de Saúde , Controle de Infecções/métodos , Assistência de Longa Duração , Viroses/prevenção & controle , Fômites/virologia , Mãos/virologia , Humanos , Levivirus/isolamento & purificação , Modelos Teóricos , Estados Unidos
13.
J Occup Environ Hyg ; 12(4): 266-75, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25436665

RESUMO

Although the number of illnesses resulting from indirect viral pathogen transmission could be substantial, it is difficult to estimate the relative risks because of the wide variation and uncertainty in human behavior, variable viral concentrations on fomites, and other exposure factors. The purpose of this study was to evaluate the micro-activity approach for assessment of microbial risk by adapting a mathematical model to estimate probability of viral infection from indirect transmission. To evaluate the model, measurements of phage loading on fomites and hands collected before and after implementation of a Healthy Workplace Project intervention were used. Parameter distributions were developed from these data, as well as for micro-activity rates, contact surface areas, phage transfer efficiencies, and inactivation rates. Following the Monte Carlo simulations (n = 1,000), the estimated phage loading on hands was not significantly different from the loading of phage on hands measured in the experimental trials. The model was then used to demonstrate that the Healthy Workplace Project intervention significantly reduced risk of infection by 77% for rotavirus and rhinovirus. This is the first published study to successfully evaluate a model focused on the indirect transmission of viruses via hand contact with measured data and provide an assessment of the micro-activity approach to microbial risk evaluation.


Assuntos
Transmissão de Doença Infecciosa/estatística & dados numéricos , Microbiologia Ambiental , Mãos/virologia , Higiene , Local de Trabalho , Transmissão de Doença Infecciosa/prevenção & controle , Fômites/virologia , Desinfecção das Mãos , Humanos , Levivirus/isolamento & purificação , Modelos Teóricos , Infecções por Picornaviridae/transmissão , Medição de Risco , Infecções por Rotavirus/transmissão , Vírus
14.
Food Environ Virol ; 6(3): 175-81, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25005587

RESUMO

The goals of this study were to observe the spread of viruses in a hotel setting and to assess the effectiveness of a hygiene intervention in reducing their spread. Selected fomites in one hotel room were inoculated with bacteriophage ϕx-174, and fomites in a conference center within the same hotel were inoculated using bacteriophage MS2. Cleaning of the contaminated room resulted in the spread of viruses to other rooms by the housekeeping staff. Furthermore, viruses were transferred by hotel guests to the conference center and a communal kitchen area. Additionally, conference attendees transferred viruses from the conference center to their hotel rooms and a communal kitchen area. This study demonstrated how viruses can be spread throughout a hotel setting by both housekeepers and guests. A hygiene intervention, which included providing hand hygiene products and facial tissues to the guests and disinfecting solutions with disposable wipes to the housekeeping staff, was successful in reducing the spread of viruses between the hotel guest rooms and conference center. The hygiene intervention resulted in significantly reduced transfer of the ϕx-174 between the contaminated hotel room and other hotel rooms, communal areas, and the conference center (p = 0.02).


Assuntos
Desinfetantes/farmacologia , Desinfecção/métodos , Higiene das Mãos/métodos , Zeladoria/métodos , Viroses/transmissão , Vírus/efeitos dos fármacos , Bacteriófagos/efeitos dos fármacos , Bacteriófagos/crescimento & desenvolvimento , Desinfecção/instrumentação , Fômites/virologia , Higiene das Mãos/instrumentação , Humanos , Viroses/prevenção & controle , Viroses/virologia , Vírus/crescimento & desenvolvimento , Recursos Humanos
15.
J Cosmet Sci ; 65(2): 89-101, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24797025

RESUMO

Development of more effective products for cleansing the skin of microorganisms is enhanced by improved understanding of the mechanisms of attachment, as well as potential removal strategies. This paper describes an in vitro method for use of the cationic exchanger carboxymethylcellulose (CMC) to enhance the removal of the yeast Candida albicans as measured in vitro using human skin tape strippings. Several negatively charged and cationic exchanger compounds were evaluated using a visual release method to determine their ability to prompt release of C. albicans from human skin strips. CMC was further tested using a viable count method to assess its ability to effectively release the yeast from skin strips and to evaluate the effects of pH on CMC performance. CMC microparticles were found to release greater than 95% of bound C. albicans from the skin strips over a broad range of pH values. Interaction of CMC with the overall skin charge appears to result in detachment of C. albicans, a response suggesting that anionic particles may facilitate C. albicans removal from skin.


Assuntos
Candida albicans/efeitos dos fármacos , Candida albicans/isolamento & purificação , Carboximetilcelulose Sódica/farmacologia , Contagem de Colônia Microbiana/métodos , Pele/microbiologia , Adulto , Candida albicans/metabolismo , Carboximetilcelulose Sódica/química , Carboximetilcelulose Sódica/metabolismo , Humanos , Concentração de Íons de Hidrogênio , Masculino , Pele/efeitos dos fármacos , Fatores de Tempo
16.
J Am Chem Soc ; 135(21): 7869-82, 2013 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-23647400

RESUMO

Methods to intercept bacterial quorum sensing (QS) have attracted significant attention as potential anti-infective therapies. Staphylococcus aureus is a major human pathogen that utilizes autoinducing peptide (AIP) signals to mediate QS and thereby regulate virulence. S. aureus strains are categorized into four groups (I-IV) according to their AIP signal and cognate extracellular receptor, AgrC. Each group is associated with a certain disease profile, and S. aureus group-III strains are responsible for toxic shock syndrome and have been underestimated in other infections to date. A limited set of non-native AIP analogs have been shown to inhibit AgrC receptors; such compounds represent promising tools to study QS pathways in S. aureus . We seek to expand this set of chemical probes and report herein the first design, synthesis, and biological testing of AIP-III mimetics. A set of non-native peptides was identified that can inhibit all four of the AgrC receptors (I-IV) with picomolar IC50 values in reporter strains. These analogs also blocked hemolysis by wild-type S. aureus group I-IV strains-a virulence trait under the control of QS-at picomolar concentrations. Moreover, four of the lead AgrC inhibitors were capable of attenuating the production of toxic shock syndrome toxin-1 (also under the control of QS) by over 80% at nanomolar concentrations in a wild-type S. aureus group-III strain. These peptides represent, to our knowledge, the most potent synthetic inhibitors of QS in S. aureus known, and constitute new and readily accessible chemical tools for the study of the AgrC system and virulence in this deadly pathogen.


Assuntos
Proteínas de Bactérias/química , Peptídeos/farmacologia , Percepção de Quorum/efeitos dos fármacos , Staphylococcus aureus/fisiologia , Sequência de Aminoácidos , Ensaio de Imunoadsorção Enzimática , Concentração Inibidora 50 , Dados de Sequência Molecular , Peptídeos/química , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/metabolismo
17.
Am J Infect Control ; 41(10): 912-5, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23523522

RESUMO

BACKGROUND: Hospital cleaning practices are critical to the prevention of nosocomial infection transmission. To this end, cloth towels soaked in disinfectants are commonly used to clean and disinfect hospital surfaces. Cloth cleaning towels have been linked to an outbreak of Bacillus cereus and have been shown to reduce the effectiveness of commonly used quaternary ammonium disinfectants. Thus, it is important to determine whether the reuse of cloth towels increases the risk of pathogen transmission in hospitals. METHODS: The goal of this project was to determine the effects of laundry and cleaning practices commonly used in hospitals for washing, storage, and disinfection of cloth cleaning towels on their microbial loads. RESULTS: Our results indicate that cloth towels used for cleaning hospital rooms contained high numbers of microbial contaminants. CONCLUSIONS: In this case, hospital laundering practices appear insufficient to remove microbial contaminants and may even add contaminants to the towels. Furthermore, it has been previously reported that towels can interfere with the action of common hospital disinfectants. Either independently or in combination, these 2 factors may increase the risk for transmission of pathogens in hospitals. These observations indicate the need to critically reevaluate current hospital cleaning practices associated with reuse of cloth towels.


Assuntos
Bactérias/isolamento & purificação , Desinfecção/métodos , Fungos/isolamento & purificação , Zeladoria Hospitalar/métodos , Têxteis/microbiologia , Carga Bacteriana , Contagem de Colônia Microbiana , Hospitais , Humanos
18.
Skin Res Technol ; 19(1): e453-8, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22882623

RESUMO

BACKGROUND: The ideal gentle cleansing product is one that effectively removes soils while minimizing damage to the skin. Thus, measuring physical abrasion caused by cleansing tissues is critical to the continued development of gentle cleansing products. Current analysis of cleansing materials for skin gentleness is time consuming and requires expensive human subject testing. This report describes the development of a rapid and inexpensive bench assay for the assessment of skin abrasion caused by wiping. METHODS: Coefficient of friction (COF) evaluations using bench methods were compared with results from clinical studies of repeated wiping and with confocal visualizations of excised skin. A Monitor/Slip and Friction instrument (model 32-06; TMI, Amityville, NY, USA) was used to measure tissue friction on simulated skin (Vitro-Skin, N19-5X; IMS, Milford, CT, USA). Clinical data from a 4-day repetitive forearm wiping study measuring transepidermal water loss (TEWL) in 30 subjects was compared with results from the bench top assay. In addition, excised skin samples were also treated using the COF bench assay and examined using confocal microscopy to visualize stratum corneum damage caused by wiping. RESULTS: Using the bench COF assay, we were able to distinguish between bath tissue codes by comparing average static friction value (ASFV) for the test codes, where lower ASFV indicated less abrasive tissue. The ASFV followed the same gentleness trend observed in the clinical study. Confocal microscopy of excised skin wiped with the same materials indicated stratum corneum damage consistent with the bench COF and clinical TEWL observations. CONCLUSION: We observed significant correlation between bench and clinical methods for measuring skin damage caused by wiping of skin with tissue. The bench method will facilitate rapid and inexpensive skin gentleness assessment of cleansing materials.


Assuntos
Produtos Domésticos/efeitos adversos , Papel , Higiene da Pele/efeitos adversos , Pele/lesões , Pele/patologia , Detergentes/efeitos adversos , Antebraço , Fricção , Humanos , Técnicas In Vitro , Teste de Materiais/métodos , Microscopia Confocal , Fragilidade Osmótica , Valor Preditivo dos Testes , Pele/metabolismo , Perda Insensível de Água
19.
Appl Environ Microbiol ; 55(8): 2079-2081, 1989 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16347997

RESUMO

Lipomyces starkeyi ATCC 20825 is a derepressed mutant derived from L. starkeyi ATCC 12659. It requires the presence of an inducer before it produces dextranase. This study was undertaken to determine the most efficient, commercially feasible method for inducing this enzyme. The following compounds induced dextranase synthesis: 1-O-beta-methyl-glucopyranoside, 1-O-alpha-methyl-glucopyranoside, dextran, isomaltopentose, isomaltotetraose, isomaltotriose, and isomaltose. 1-O-beta-Methyl-glucopyranoside was found to be a gratuitous inducer. Early in the growth phase, cells produced higher specific levels of enzyme than they did in late log phase. The length of exposure of the yeast cells to the inducer also affected the amount of dextranase produced. The maximum amount of enzyme was produced after 12 h of exposure to the inducer. The saturation concentration was the same for all inducers tested, i.e., approximately 1 mg of inducer for every 2 x 10 cells.

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