Effet antibactérien et anti-biofilm de trois espèces de <Emphasis Type="Italic">Mentha</Emphasis> : <Emphasis Type="Italic">Mentha spicata</Emphasis>, <Emphasis Type="Italic">Mentha pulegium</Emphasis> et <Emphasis Type="Italic">Mentha piperita</Emphasis>

In the first part of this study, we were proceeded to the evaluation of the antibacterial effect of the organic extracts from the leaves of three plant species of Mentha against six pathogenic bacterial strains including Gram (-) bacteria and Gram (+) bacteria. The methods of diffusion in solid and micro-dilution method in liquid medium were used for antibacterial testing. The results showed that nonpolar extracts are much more active then polar extracts. The Gram (+) bacteria showed more sensitive than the Gram (-) bacteria. S. aureus was shown to be the most sensitive of all bacteria testing in this study, it was sensitive against all extracts include that aqueous. All aqueous extracts have no antibacterial activity with the highest concentration used (12 mg/ml) against the five other strains.In the second part, non-polar extracts were tested for their anti-biofilm effect against biofilms formed by S. aureus and E. coli in 48 hours. All extracts showed a spectacular antibiofilm effect with elimination of all the biofilms formed after 30 min of treatment.     

Étude botanique et activité antifongique <Emphasis Type="Italic">in vitro</Emphasis> sur <Emphasis Type="Italic">Trichophyton mentagrophytes</Emphasis> de <Emphasis Type="Italic">Bersama abyssinica</Emphasis> Fresen. (Melianthaceae)

Objective: To evaluate the antifungal activity of the species most sought to improve the health of our poor people and especially immunocompromised.An ethnobotanical study conducted in the Department of Transua using questionnaires collected information on the therapeutic uses of antimicrobial plants in the region. It helped to inventory several plant species. Bersama abyssinica taxon is most stressed. Antifungal activity was tested using double dilution method in angle sloping tubes on Sabouraud Agar. Three extracts (ETA, EE70% and ERA) of tested leaves have antifungal activity on Trichophyton mentagrophytes. ERA was the most active (MIC=0.195±0.000 mg/ml, IC₅₀=0.024±0.010 mg/ml and MFC=0.195±0.000 mg/ml). These results reveal that the Department of Transua contain antimicrobial plants. Bersama abyssinica have antifungal activity on Trichophyton mentagrophytes. These results justify the use of this plant in the traditional treatment of fungal infections and opportunistic diseases associated with AIDS.     

Propriétés antioxydantes et antimicrobiennes des extraits de <Emphasis Type="Italic">Myrtus nivellei</Emphasis> Batt et Trab. obtenus <Emphasis Type="Italic">in situ</Emphasis> et <Emphasis Type="Italic">in vitro</Emphasis>

This work provides a contribution to the investigation and valorization of the Sahara-endemic plant: Myrtus nivellei Batt & Trab and the evaluation of the antioxidant effect of methanolic extracts harvested in situ, and in vitro propagated calli of this plant. Several spectrophotometric analyzes were performed, showing that the in situ methanolic extract was richer in polyphenols than the in vitro methanolic extract. Also, It expressed a good power to scavenge free radicals (EC50 = 0.98 mg/ml) and a great capacity to inhibit the peroxidation of linoleic acid estimated as 74.01%, largely higher than the ascorbic acid (50.57%) used as a positif control. However, the methanolic extracts of calli expressed the best ferric reducing power estimated as 66.71%. A very good antimicrobial activity was recorded for the extract of the plant harvested in situ, particularly against S. aureus (MIC=2.25 mg/ml), also against S. pneumoniae, S. flexineri, S. typhi and C. albicans (MIC=4.5 mg/ml). However, the calli extracts had presented no anti-microbial effect.     

Étude de l’activité des extraits de feuilles de <Emphasis Type="Italic">Punica granatum</Emphasis> Linn sur <Emphasis Type="Italic">Candida albicans</Emphasis> et <Emphasis Type="Italic">Rhodotorula spp</Emphasis>

Medicinal plants have been used for centuries as remedies for human diseases, because of their bioactive components contained in therapeutic extracts. Among these we find Punica granatum considered as food, medicinal plant and as an ornamental, which has not yet revealed all its secrets. The aim of our study was to evaluate the antifungal activity of two methanolic and ethanolic leaf extracts of pomegranate. For this purpose, the extracts were tested on clinical strains (. albicans clinical (c), R. spp) and reference C. albicans (IP 444, ATCC 1231), using the agar diffusion method. The ethanol extract produced greater inhibitions zones than those obtained with the methanol extract; other parameters are to be evaluated in our study namely the determination of the minimum inhibitory concentration (MIC) and minimum fungicidal concentration of inhibition zones (MFC) of tested strains.     

Antagonistic Actinomycetes Mediated Resistance in <Emphasis Type="Italic">Solanum lycopersicon</Emphasis> Mill. Against <Emphasis Type="Italic">Rhizoctonia solani</Emphasis> Kühn

Actinomycetes are a major group of beneficial microbes, which can be explored as spanking alternative to chemical fungicides for providing defense against phytopathogens. Rhizoctonia solani is a major havoc causing severe loss to many crops. Biological measures for fungal disease management are desired over the available chemical/synthetic fungicides owing to their safety towards non-target organisms. In the present study, 34 actinomycetes were isolated from vermicompost. Out of them, twelve revealed antifungal activity related to Indole acetic acid (IAA) production, siderophores and plant growth promotion. Under greenhouse and field conditions, these potent strains remarkably enhanced yield attributes and disease diminution as compared to untreated control. A significant disease reduction of 47–63 % against R. solani was observed in tomato plants pretreated with actinomycetes. Furthermore, induction in defense related enzymes such as peroxidase, polyphenol oxidase, phenylalanine ammonia lyase, accumulation of phenolics and flavonoids were also observed in actinomycetes treated plants. Morphological and molecular characterization analysis identified these potent isolates as Streptomyces sp. NBM3, Streptomyces sp. NBM2, Streptomyces sp. NBM1, Streptomyces sp. NBM12 and Streptomyces sp. NBM8. The present findings suggest that these microbes can be utilized for significant enhancement of plant growth and augmentation of defense related enzymes in order to cope up with R. solani induced stress, thereby contributing to crop health.     

Propriétés antifongiques des huiles essentielles des feuilles de <Emphasis Type="Italic">Citrus</Emphasis> vis-à-vis <Emphasis Type="Italic">d’Alternaria alternata</Emphasis> et <Emphasis Type="Italic">Penicillium sp</Emphasis> in vitro

Résumé

Les huiles essentielles ont été extraites par hydrodistillation à partir des feuilles de citrus. Les rendements les plus importants ont été enregistrés avec Citrus limon L (1.02%) et Citrus sinensis (0.96%). Les résultats de l’activité antifongique des huiles essentielles des feuilles de citrus montrent un pouvoir inhibiteur des huiles essentielles de Citrus aurantium, Citrus limon et Citrus reticulata sur la croissance mycélienne radiale d’Alternaria alternata et Penicillium sp. Ils montrent également que l’activité antifongique augmente avec la concentration des huiles essentielles testées. Celles-ci peuvent être utilisées comme agents antifongiques potentiels pour lutter contre les maladies fongiques des plantes.

     

Targeted Ultrasound Contrast Imaging of Matrix Metalloproteinase-2 in Ischemia–Reperfusion Rat Model: <Emphasis Type="Italic">Ex Vivo</Emphasis> and <Emphasis Type="Italic">In Vivo</Emphasis> Studies

Purpose  

We hypothesized that post-myocardial ischemia–reperfusion (I/R) remodeling associated matrix metalloproteinase-2 (MMP₂) activation could be detected by using novel MMP₂ targeted ultrasound imaging.     

L’anis vert (<Emphasis Type="Italic">Pimpinella anisum L.</Emphasis>)

Résumé: Dans cet article, lauteur donne des informations sur lutilisation de lanis vert, Pimpinella anisum L., sous forme de tisane. Il expose rapidement laspect historique concernant notamment la médecine traditionnelle et plus particulièrement celle dEurope centrale. Il propose des formulations de tisanes encore utilisables de nos jours en phytothérapie quotidienne.     

Impact of antifungal treatment on <Emphasis Type="Italic">Candida</Emphasis>–<Emphasis Type="Italic">Pseudomonas</Emphasis> interaction: a preliminary retrospective case–control study

OBJECTIVE: A pathogenic interaction between Candida albicans and Pseudomonas aeruginosa has recently been demonstrated. In addition, experimental and clinical studies identified Candida spp. tracheobronchial colonization as a risk factor for P. aeruginosa pneumonia. The aim of this study was to determine the impact of antifungal treatment on ventilator-associated pneumonia (VAP) or tracheobronchial colonization due to P. aeruginosa. DESIGN AND SETTING: Retrospective observational case-control study conducted in a 30-bed ICU during a 1-year period. PATIENTS AND METHODS: One hundred and two patients intubated and ventilated for longer than 48 h with tracheobronchial colonization by Candida spp. Routine screening for Candida spp. and P. aeruginosa was performed at ICU admission and weekly. Antifungal treatment was based on medical staff decisions. Patients with P. aeruginosa VAP or tracheobronchial colonization were matched (1:2) with patients without P. aeruginosa VAP or tracheobronchial colonization. In case and control patients, risk factors for P. aeruginosa VAP or tracheobronchial colonization were determined using univariate and multivariate analyses. RESULTS: Thirty-six patients (35%) received antifungal treatment. Nineteen patients (18%) developed a P. aeruginosa VAP or tracheobronchial colonization, and all were successfully matched. Antifungal treatment [31% vs 60%; p=0.037, OR (95% CI)=0.67 (0.45-0.90)], and duration of antifungal treatment (7+/-11 vs 14+/-14 days; p=0.045, in case and control patients respectively) were significantly associated with reduced risk for P. aeruginosa VAP or tracheobronchial colonization. Antifungal treatment was the only variable independently associated with P. aeruginosa VAP or tracheobronchial colonization (OR=0.68, 95% CI=0.49-0.90, p=0.046). CONCLUSION: In patients with Candida spp. tracheobronchial colonization, antifungal treatment may be associated with reduced risk for P. aeruginosa VAP or tracheobronchial colonization.     

Can mupirocin prevent methicillin-resistant <Emphasis Type="Italic">Staphylococcus aureus</Emphasis> infections?

In a retrospective study, Dr Muller and colleagues have assessed the efficacy of mupirocin nasal ointment alongside hygienic measures in methicillin-resistant Staphylococcus aureus (MRSA)-positive patients admitted to the intensive care unit (ICU). Their findings, which suggest that intranasal mupirocin can prevent ICU-related MRSA infections, need confirmation in a well-designed clinical trial. In general: early identification, isolation and treatment of all MRSA carriers, including health care workers, and disinfection of contaminated environments, are the main 'ingredients' of an effective MRSA 'search and destroy' program.     

Direct detection by real-time PCR of <Emphasis Type="Italic">ftsI</Emphasis> gene mutations affecting MICs of β-lactam agents for <Emphasis Type="Italic">Haemophilus influenzae</Emphasis> isolates from meningitis

One resistance mechanism of Haemophilus influenzae to ampicillin involves decreased affinity of penicillin-binding protein (PBP) 3 for β-lactam antibiotics reflecting amino acid substitutions in PBP3 encoded by the ftsI gene. Three amino acid substitutions, Ser385Thr, Arg517His, and Asn526Lys, are especially responsible for β-lactam resistance. We constructed a new real-time polymerase chain reaction (PCR) to directly detect these substitutions in addition to 16S ribosomal RNA (rRNA), cap, and bla _TEM genes. Our real-time PCR was evaluated using 206 clinical H. influenzae strains isolated from pediatric patients with meningitis. Relative sensitivities and specificities of real-time PCR were 90.5–100% and 96.3–100% for all resistance classes compared with our previously reported conventional PCR. In addition, real-time PCR shortened time required from 3 h by conventional PCR to 1.5 h. When correlations between combinations of amino acid substitutions in the ftsI gene detected by real-time PCR and minimum inhibitory concentrations (MICs) of β-lactam antibiotics were evaluated, MIC₉₀s of ampicillin for β-lactamase-nonproducing ampicillin-intermediate-resistant strains with Asn526Lys, β-lactamase-nonproducing, ampicillin-resistant strains with Ser385Thr, and β-lactamase-nonproducing ampicillin-resistant strains with both Asn526Lys and Ser385Thr, respectively, were two, four, and eight times higher than those for sensitive strains. Similarly, MIC₉₀s of cephalosporins for these strains, respectively, were two, 16–32, and 16–32 times higher than those for sensitive strains. Thus, real-time PCR can guide antibiotic use.     

Infections respiratoires virales à <Emphasis Type="Italic">herpesviridae</Emphasis> en réanimation

Herpesviridae, including herpes simplex virus (HSV) and cytomegalovirus (CMV), are commonly detected in the respiratory tract of non-immunocompromised patients receiving mechanical ventilation. Although their detection usually involves viral reactivation without the involvement of pulmonary tissue, viral lung disease may occur in a particular population of patients. Although histological examination for specific cytopathic effects forms the basis of diagnosis, the use of modern virological tests (amplification using real-time polymerase chain reaction to estimate the vial load) should replace the histological tests in the near future. HSV bronchopneumonitis is associated with the reactivation of HSV in oropharyngeal and oral-labial lesions. It seems to clearly affect patients’ outcome due to prolonged mechanical ventilation and length of stay in the intensive care unit (ICU). However, only interventional studies will be able to determine its real impact. To date, use of acyclovir in these patients remains to be assessed. Although CMV reactivation in the blood is frequent in ICU patients, CMV pneumonia is difficult to diagnose because of the cumbersomeness of the procedure (open lung biopsies). Its true prognosis remains uncertain. The use of ganciclovir in this subset of patients also remains to be assessed.     

Year in review 2013: <Emphasis Type="Italic">Critical Care</Emphasis> – sepsis

This review presents key publications from the research field of sepsis published in Critical Care and other relevant journals during 2013. The results of these experimental studies and clinical trials are discussed in the context of current scientific and clinical background. The discussion highlights and summarises articles on four main topics: sepsis pathogenesis, diagnostic and prognostic biomarkers, potential new therapies, and epidemiologic and outcome studies.