A study on the ability of quaternary ammonium groups attached to a polyurethane foam wound dressing to inhibit bacterial attachment and biofilm formation

Bacterial infection of acute and chronic wounds impedes wound healing significantly. Part of this impediment is the ability of bacterial pathogens to grow in wound dressings. In this study, we examined the effectiveness of a polyurethane (PU) foam wound dressings coated with poly diallyl‐dimethylammonium chloride (pDADMAC‐PU) to inhibit the growth and biofilm development by three main wound pathogens, Staphylococcus aureus, Pseudomonas aeruginosa, and Acinetobacter baumannii, within the wound dressing. pDADMAC‐PU inhibited the growth of all three pathogens. Time‐kill curves were conducted both with and without serum to determine the killing kinetic of pDADMAC‐PU. pDADMAC‐PU killed S. aureus, A. baumannii, and P. aeruginosa. The effect of pDADMAC‐PU on biofilm development was analyzed quantitatively and qualitatively. Quantitative analysis, colony‐forming unit assay, revealed that pDADMAC‐PU dressing produced more than eight log reduction in biofilm formation by each pathogen. Visualization of the biofilms by either confocal laser scanning microscopy or scanning electron microscopy confirmed these findings. In addition, it was found that the pDADMAC‐PU‐treated foam totally inhibited migration of bacteria through the foam for all three bacterial strains. These results suggest that pDADMAC‐PU is an effective wound dressing that inhibits the growth of wound pathogens both within the wound and in the wound dressing.     

Coenzyme Q10 prevents human lens epithelial cells from light‐induced apoptotic cell death by reducing oxidative stress and stabilizing BAX / Bcl‐2 ratio

Background: Cataract is one of the most prevalent eye disease and a major cause for legal blindness in the world. Beside others, cumulative light‐exposure and apoptotic cell death are significantly associated with cataract development. In contrast, supplementation with antioxidants has been suggested to prevent premature cataractogenesis. This study investigates possible protective effects of Coenzyme Q10 (CoQ10) regarding light‐induced stress and apoptotic cell death in human lens epithelial cells (LEC). Methods: Human LEC were either pre‐incubated with CoQ10 or not and then exposed to white light. After 10–40 min of irradiation viability, induction of intracellular reactive oxygen species (ROS), apoptosis and cell death was determined. Expression of apoptotic BAX and anti‐apoptotic Bcl‐2 protein and their mRNA were determined by RT‐PCR and Western blot analysis. Results: Light exposure decreased LEC viability and Bcl‐2 expression and increased intracellular ROS, apoptotic cell death, and BAX expression in a time‐of‐irradiation‐dependent manner. Phototoxic cell death and apoptosis, as well as decrease of Bcl‐2 and increase in BAX expression was significantly reduced, when cells were pre‐incubated with CoQ10. Conclusions: In this study, CoQ10 significantly reduced light‐induced LEC‐damage and attenuated phototoxic effects on BAX and Bcl‐2 expression. Therefore, CoQ10 supplementation might also be useful in preventing LEC death and consecutive cataract formation in vivo.     

The influence of childhood atopic dermatitis on health of mothers,and its impact on Asian families

Ho RCM, Giam YC, Ng TP, Mak A, Goh D, Zhang MWB, Cheak A, Van Bever HP. The influence of childhood atopic dermatitis on health of mothers, and its impact on Asian families.
Pediatr Allergy Immunol 2010: 21: 501–507.
© 2010 John Wiley & Sons A/S This study examines maternal perceptions of paediatric atopic dermatitis (AD) on family and determines risk factors including severity of AD, maternal physical and mental health (MH), quality of life of patients and sociodemographics which predict a negative family impact. A cross‐sectional assessment using the Dermatitis Family Impact Questionnaire Scale to assess the impact of AD on family, Infant’s Dermatitis Quality of Life Index (<5‐yrs old) or Children’s Dermatitis Life Quality Index (5–17 yrs old) was used to measure health‐related quality of life (HRQOL) of paediatric patients with AD. A 12‐item Short‐Form Health Survey (SF‐12) was used to assess physical and MH of their mothers. Risk factors of adverse family impact were assessed using multiple regression analysis. One hundred and four patients with AD and their mothers were studied. Their mean ages (±s.d.) were respectively 6.4 ± 4.3 and 37.2 ± 6.6 yrs. In multiple regression analysis, Severity Scoring of Atopic Dermatitis (SCORAD) appeared to be associated with negative family impact and the association remained significant after adjustment for bio‐psycho‐social factors and HRQOL of patients. The association remained insignificant after adjustment for physical and MH of the mothers. Our results show that the severity of paediatric AD leads to negative family impact through reduction of physical and MH of the mothers, and is independent of patients’ HRQOL and sociodemographics. The current approach for managing paediatric AD in Asian society could include early multidisciplinary intervention, aiming at enhancing physical and MH of mothers while minimizing negative impact on family and social isolation. Further research will be welcomed as the results of this study mainly applied to Asian society which could be different to populations from other geographic areas.     

Elective removal of cuffed central venous catheters in children

Background Subcutaneously tunneled, cuffed central venous catheters (CVCs) are commonly used in children undergoing cytotoxic chemotherapy or hematopoietic stem-cell transplantation. When their use is no longer indicated or precluded by mechanical or infectious complications, CVCs have to be removed. General instructions on how cuffed CVC should be removed are available in the medical texts but none is adapted for use in children. Materials and methods A literature search from the MEDLINE and EMBASE to identify articles describing the procedure of removing CVC or complications arising from the procedure was carried out. Results Specific guidance on the removal of CVC in children was not found. Venous air embolism appeared to be the most common complication associated with catheter removal but none involved pediatric patients. On the other hand, three out of the five incidents of catheter fracture with or without embolization happened in children. Conclusion Further studies are needed to define the optimal management of CVC removal in pediatric patients. A sequence of positioning the child, use of sedation, dissecting out the cuff, pulling off the catheter, closing the exit wound, and handling of the removed catheter is suggested.     

The NAD(P)H oxidase inhibitor apocynin improves endothelial NO/superoxide balance and lowers effectively blood pressure in spontaneously hypertensive rats: comparison to calcium channel blockade

The vascular NAD(P)H oxidase contributes to endothelial dysfunction and high blood pressure in the spontaneously hypertensive rat by enhancing superoxide production. We investigated the effects of apocynin, a NAD(P)H oxidase inhibitor, on blood pressure and vascular radical and nitric oxide formation in SHR and compared its effects to the calcium channel blocker nifedipine. Apocynin (over four weeks) lowered systolic blood pressure significantly and as effectively as nifedipine. Both apocynin and nifedipine significantly reduced superoxide production. In parallel, vascular nitric oxide production and ecNOS activity was significantly increased by apocynin treatment. Therefore, apocynin may be an effective antihypertensive drug in essential hypertension.