Lichen Polyphenolic Compounds for the Eradication of Candida albicans Biofilms

Lichens, due to their symbiotic nature (association between fungi and algae), constitute a chemical factory of original compounds. Polyphenolic compounds (depsides and depsidones) are the main constituents of lichens and are exclusively biosynthesized by these organisms. A panel of 11 polyphenols was evaluated for their anti-biofilm activity against Candida albicans biofilms on the maturation phase (anti-maturation) (MMIC₅₀) as well as on preformed 24-h-old biofilm (anti-biofilm) (MBIC₅₀) using the XTT assay. Minimum inhibitory concentrations of compounds (MICs) against C. albicans planktonic yeast were also determined using a broth microdilution method. While none of the tested compounds were active against planktonic cells (IC₅₀ > 100 µg/ml), three depsides slowed the biofilm maturation (MMIC₅₀ ≤12.5 µg/ml after 48 h of contact with Candida cells). Evernic acid was able to both slow the maturation and reduce the already formed biofilms with MBIC₅₀ ≤12.5 µg/ml after 48 h of contact with the biofilm. This compound shows a weak toxicity against HeLa cells (22%) at the minimal active concentration and no hemolytic activity at 100 µg/ml. Microscopic observations of evernic acid and optimization of its solubility were performed to further study this compound. This work confirmed the anti-biofilm potential of depsides, especially evernic acid, and allows to establish the structure-activity relationships to better explain the anti-biofilm potential of these compounds.

Accuracy assessment for three fiberoptic pulmonary artery catheters for SvO2 monitoring

OBJECTIVE

To compare values of SvO2 obtained by reflectance spectrophotometry continuous monitoring with those obtained from blood samples measurements by transmission spectrophotometry (Co-Oximetry).

DESIGN

Values of SvO2 recorded by three pulmonary artery catheters for continuous monitoring, SAT1, SAT2 and Oximetrix3 (OX3), were compared in a prospective manner to those measured on blood samples by a Co-Oximeter, using the statistical analysis of Bland and Altman.

SETTING

Adult intensive care unit in an University Hospital.

PATIENTS

37 patients admitted for acute respiratory failure and/or shock who required hemodynamic monitoring.

MAIN RESULTS

The bias (average under- or overestimation) was small for all comparative measurements: +1.3, -0.2 and +1.0 sat% for SAT1, SAT2 and OX3, respectively. However, limits of agreement were only acceptable for SAT2 (-8.3 to +7.9 sat%) and OX3 (-6.7 to +8.6 sat%), but not for SAT1 (-23.3 to +25.9 sat%). No significant drift during 24 h was found with the three catheters. However, in vitro calibration was only found acceptable for SAT2 and OX3. The results were not influenced by the numbers of wavelengths of the device (2 for SAT1 and SAT2, and 3 for OX3) nor did they correlate with any of the hemodynamic and biochemical variables tested.

CONCLUSION

For usual monitoring in the ICU, SAT2 and OX3, gave SvO2 values which are in acceptable agreement with SvO2 measured on blood samples by Co-Oximetry.

Posttraumatic intracerebral pneumatocele after ventilation with a mask: case report

We report an unusual case of posttraumatic tension pneumatocele following manually operated ventilation with a face mask. This is a rare cause of such injury. Diagnosis is confirmed by skull films and CT scans. Early surgical treatment may be required.

[Traumatic rupture of the aorta diagnosed by transesophageal echocardiography. Apropos of a case and review of the literature]

The authors report the case of subadventitial rupture of the isthmus of the aorta due to trauma, diagnosed by transoesophageal echocardiography. The role of transoesophageal echocardiography compared with conventional diagnostic techniques is discussed. This method of investigation is a very good diagnostic tool in cases of closed trauma of the thorax.

[Cholestatic hepatitis caused by ketoconazole]

The authors report a new Ketoconazole-induced hepatitis in which clinical, chemical and histological features show evidence of a cholestatic injury in a 62 yrs-old female recovering once therapy is stopped. In this case-report, delay of onset of the illness is very short for a 200 mg-a-day prescription and no feature leads towards an immune response. This, may be, means that Ketoconazole-induced hepatitis should be led by an idiosyncrasic mechanism. Even if fatal hepatitis are rare, prescriptors have to beware of this therapy.