Effects of Verapamil and Two Bisbenzylisoquinolines, Curine and Guattegaumerine Extracted from on the Inhibition of ABC Transporters from .

The biological effects of alkaloids, curine, guattegaumerine, and verapamil, on were investigated. These molecules did not inhibit growth but increased the sensitivity of this bacterium to carbenicillin, novobiocin, and erythromycin. The results of another study indicate that curine and guattegaumerine were competitors of verapamil and acted as inhibitors of eukaryotic ABCB1 efflux pump.

Norepinephrine and Serotonin Can Modulate the Behavior of the Probiotic NCIMB10415 towards the Host: Is a Putative Surface Sensor Involved?

The human gut microbiota has co-evolved with humans by exchanging bidirectional signals. This study aims at deepening the knowledge of this crucial relationship by analyzing phenotypic and interactive responses of the probiotic NCIMB10415 ( SF68) to the top-down signals norepinephrine (NE) and serotonin (5HT), two neuroactive molecules abundant in the gut. We treated NCIMB10415 with 100 µM NE and 50 µM 5HT and tested its ability to form static biofilm (Confocal Laser Scanning Microscopy), adhere to the Caco-2/TC7 monolayer, affect the epithelial barrier function (Transepithelial Electrical Resistance) and human dendritic cells (DC) maturation, differentiation, and cytokines production.

Pseudomonas aeruginosa Biofilm Dispersion by the Human Atrial Natriuretic Peptide.

Pseudomonas aeruginosa biofilms cause chronic, antibiotic tolerant infections in wounds and lungs. Numerous recent studies demonstrate that bacteria can detect human communication compounds through specific sensor/receptor tools that modulate bacterial physiology. Consequently, interfering with these mechanisms offers an exciting opportunity to directly affect the infection process.

Effect of 17β-estradiol on a human vaginal Lactobacillus crispatus strain.

Lactobacilli and estrogens play essential roles in vaginal homeostasis. We investigated the potential direct effect of 17β-estradiol on a vaginal strain of Lactobacillus crispatus, the major bacterial species of the vaginal microbiota. 17β-estradiol (10 to 10 M) had no effect on L.

Identification of the PA1113 Gene Product as an ABC Transporter Involved in the Uptake of Carbenicillin in PAO1.

The resistance of to antibiotics is multi factorial and complex. Whereas efflux pumps such as MexAB-OprM have been thought to predominate, here we show that a novel ATP Binding Cassette (ABC) transporter that mediates influx of carbenicillin from the periplasm to the cytoplasm and away from its cell wall target plays an important role in the resistance of to this antibiotic. Treatment of with verapamil, an inhibitor of ABC transporters in eukaryotic cells, increases its sensitivity to carbenicillin.

Influence of Catecholamines (Epinephrine/Norepinephrine) on Biofilm Formation and Adhesion in Pathogenic and Probiotic Strains of .

has controversial status due to its emerging role in nosocomial infections, while some strains with beneficial effects are used as probiotics and starter cultures in dairy industry. These bacteria can be found as resident or transient germs in the gut or on skin, where they are continually exposed to various eukaryotic molecules. In this context, the aim of our work was to evaluate the effect of the catecholamine stress hormones, epinephrine (Epi), and norepinephrine (NE) on some trains.

Dialog between skin and its microbiota: Emergence of "Cutaneous Bacterial Endocrinology".

Microbial endocrinology is studying the response of microorganisms to hormones and neurohormones and the microbiota production of hormones-like molecules. Until now, it was mainly applied to the gut and revealed that the intestinal microbiota should be considered as a real organ in constant and bilateral interactions with the whole human body. The skin harbours the second most abundant microbiome and contains an abundance of nerve terminals and capillaries, which in addition to keratinocytes, fibroblasts, melanocytes, dendritic cells and endothelial cells, release a huge diversity of hormones and neurohormones.

Draft Genome Sequence of Lactobacillus crispatus CIP 104459, Isolated from a Vaginal Swab.

We report the draft genome sequence of CIP 104459, isolated from a human vaginal swab. This draft genome consists of 1,993,673 bp, with 36.8% G+C content and 2,024 predicted protein-encoding sequences.

Point-of-use filters for prevention of health care-acquired Legionnaires' disease: Field evaluation of a new filter product and literature review.

Background: The Centers for Medicare & Medicaid Services requires that health care facilities assess their building water systems and minimize the risk of growth and spread of Legionella and other waterborne pathogens. Increasingly, point-of-use (POU) filters are being used to prevent exposure to these pathogens. This study provides efficacy and performance specifications (membrane size, pore size, and use restrictions), which will aid in selecting POU filters.

Draft Genome Sequence of Lactobacillus crispatus Strain V4, Isolated from a Vaginal Swab from a Young Healthy Nonmenopausal Woman.

strain V4 was isolated from a vaginal swab from a healthy nonmenopausal 35-year-old French woman. We report here its draft genome sequence of 2,091,889 bp, with an average G+C content of 37.02%.

Acne and Stress: Impact of Catecholamines on .

(former ), is a bacterium characterized by high genomic variability, consisting of four subtypes and six major ribotypes. Skin is the largest neuroendocrine organ of the human body and many cutaneous hormones and neurohormones can modulate acterial physiology. Here, we investigated the effect of catecholamines, i.

Mechanism of action of the moonlighting protein EfTu as a Substance P sensor in Bacillus cereus.

The striking feature of the ubiquitous protein EfTu (Thermo unstable ribosomal Elongation factor) is its moonlighting (multifunctional) activity. Beyond its function at the ribosomal level it should be exported to the bacterial surface and act as an environmental sensor. In Bacillus cereus, and other cutaneous bacteria, it serves as a Substance P (SP) receptor and is essential for bacterial adaptation to the host.

Regulation of Monospecies and Mixed Biofilms Formation of Skin and by Human Natriuretic Peptides.

and are common representatives of the human skin microbiome. However, when these bacteria are organized in biofilm, they could be involved in several skin disorders such as acne or psoriasis. They inhabit in hollows of hair follicles and skin glands, where they form biofilms.

Different Dose-Dependent Modes of Action of C-Type Natriuretic Peptide on Biofilm Formation.

We have previously shown that the C-type Natriuretic Peptide (CNP), a peptide produced by lungs, is able to impact physiology. In the present work, the effect of CNP at different concentrations on biofilm formation was studied and the mechanisms of action of this human hormone on were deciphered. CNP was shown to inhibit dynamic biofilm formation in a dose-dependent manner without affecting the bacterial growth at any tested concentrations.

Substance P and Calcitonin Gene-Related Peptide: Key Regulators of Cutaneous Microbiota Homeostasis.

Neurohormones diffuse in sweat and epidermis leading skin bacterial microflora to be largely exposed to these host factors. Bacteria can sense a multitude of neurohormones, but their role in skin homeostasis was only investigated recently. The first study focused on substance P (SP), a neuropeptide produced in abundance by skin nerve terminals.

Requirements for nucleocapsid-mediated regulation of reverse transcription during the late steps of HIV-1 assembly.

HIV-1 is a retrovirus replicating within cells by reverse transcribing its genomic RNA (gRNA) into DNA. Within cells, virus assembly requires the structural Gag proteins with few accessory proteins, notably the viral infectivity factor (Vif) and two copies of gRNA as well as cellular factors to converge to the plasma membrane. In this process, the nucleocapsid (NC) domain of Gag binds to the packaging signal of gRNA which consists of a series of stem-loops (SL1-SL3) ensuring gRNA selection and packaging into virions.

HIV-1 nucleocapsid and ESCRT-component Tsg101 interplay prevents HIV from turning into a DNA-containing virus.

HIV-1, the agent of the AIDS pandemic, is an RNA virus that reverse transcribes its RNA genome (gRNA) into DNA, shortly after its entry into cells. Within cells, retroviral assembly requires thousands of structural Gag proteins and two copies of gRNA as well as cellular factors, which converge to the plasma membrane in a finely regulated timeline. In this process, the nucleocapsid domain of Gag (GagNC) ensures gRNA selection and packaging into virions.

Explaining geographic gradients in winter selection of landscapes by boreal caribou with implications under global changes in Eastern Canada.

Many animal species exhibit broad-scale latitudinal or longitudinal gradients in their response to biotic and abiotic components of their habitat. Although knowing the underlying mechanism of these patterns can be critical to the development of sound measures for the preservation or recovery of endangered species, few studies have yet identified which processes drive the existence of geographical gradients in habitat selection. Using extensive spatial data of broad latitudinal and longitudinal extent, we tested three hypotheses that could explain the presence of geographical gradients in landscape selection of the endangered boreal woodland caribou (Rangifer tarandus caribou) during winter in Eastern Canadian boreal forests: 1) climate-driven selection, which postulates that geographic gradients are surrogates for climatic gradients; 2) road-driven selection, which proposes that boreal caribou adjust their selection for certain habitat classes as a function of proximity to roads; and 3) an additive effect of both roads and climate.

MoMuLV and HIV-1 nucleocapsid proteins have a common role in genomic RNA packaging but different in late reverse transcription.

Retroviral nucleocapsid proteins harbor nucleic acid chaperoning activities that mostly rely on the N-terminal basic residues and the CCHC zinc finger motif. Such chaperoning is essential for virus replication, notably for genomic RNA selection and packaging in virions, and for reverse transcription of genomic RNA into DNA. Recent data revealed that HIV-1 nucleocapsid restricts reverse transcription during virus assembly--a process called late reverse transcription--suggesting a regulation between RNA packaging and late reverse transcription.

Role of HIV-1 RNA and protein determinants for the selective packaging of spliced and unspliced viral RNA and host U6 and 7SL RNA in virus particles.

HIV-1 particles contain RNA species other than the unspliced viral RNA genome. For instance, viral spliced RNAs and host 7SL and U6 RNAs are natural components that are non-randomly incorporated. To understand the mechanism of packaging selectivity, we analyzed the content of a large panel of HIV-1 variants mutated either in the 5'UTR structures of the viral RNA or in the Gag-nucleocapsid protein (GagNC).

Persistency assessment and aerobic biodegradation of selected cyclic sesquiterpenes present in essential oils.

Sesquiterpenes are ubiquitous in essential oils but an assessment of their environmental behavior is still required for their use as components of natural fragrance ingredients and oral care flavors. Persistency plays a key role in hazard and risk assessment, but the current knowledge on the biodegradation of sesquiterpenes in the aquatic environment is limited. This could have important consequences for the persistent, bioaccumulative and toxic (PBT) assessment of essential oils because most of the sesquiterpene components have a log K(OW) of >4.

Quenching of singlet molecular oxygen by Commiphora myrrha extracts and menthofuran.

The quenching activity against singlet oxygen, an actor of lipid peroxidation and DNA degradation, of the essential oil and resinoid of Commiphora myrrha from Somalia has been studied and compared to DL-alpha-tocopherol using 1,3-diphenylisobenzofuran (DPBF) as a probe. To insure that the furan ring was the site of the reaction, experiments were conducted with menthofuran. The essential oil and menthofuran show a higher activity than DL-alpha-tocopherol, suggesting their potential usefulness to neutralise this deleterious form of molecular oxygen.

Academic-community collaboration. An ecology for early childhood violence prevention.

The growing supportive evidence for multi-faceted approaches to violence prevention certainly demand that multi-agency collaborations will continue to proliferate as communities engage in early childhood prevention strategies. These collaborations often include partnerships between members of academia and community agencies that often produce unique challenges and benefits related to diverse experiences, skills, agendas, and practical constraints. This article describes the Jacksonville First and Best Teacher Initiative, an example of one such collaborative model for violence prevention, to illustrate many of the principles of effective academic-community collaborations and lessons learned in addressing the specific challenges of such programs.

Influence of pH and light on the stability of some antioxidants.

Summary Many organic molecules can be oxidized in the presence of oxygen. Light and traces of heavy metal ions catalyse the process of oxidation. The addition of a very small quantity of antioxidant to alcoholic perfumes and cosmetic bases is often made to retard auto-oxidations.