Synergistic effect of 2% chlorhexidine combined with proteolytic enzymes on biofilm disruption and killing.

AIM: To investigate the dynamics of a disinfection regimen using 1% trypsin and 1% proteinase K in combination with 2% chlorhexidine (with or without ultrasonics) using a nutrient-stressed endodontic multispecies model biofilm. METHODOLOGY: Nutrient-stressed biofilms (Propionibacterium acnes, Staphylococcus epidermidis, Actinomyces radicidentis, Streptococcus mitis and Enterococcus faecalis OMGS 3202) were grown in prepared root canals of single-rooted teeth. The treatment groups included 1% trypsin and 2% chlorhexidine (CHX), 1% proteinase K and 2% CHX (with and without ultrasonics). 2% CHX was the positive control and untreated group, and sterile saline (with and without ultrasonics) was the negative control. The biofilms were investigated using confocal laser scanning microscopy (CLSM) with live/dead staining and quantitative microbial culture. RESULTS: The trypsin and CHX group with ultrasonics was significantly more effective in reducing viable counts and the substratum coverage than those of all other groups (P < 0.05). The viable counts of the proteinase K and CHX group used with (4.26 ± 0.58 log10  cfu mL(-1) ) or without ultrasonics (5.05 ± 1.36 log10  cfu mL(-1) ) were significantly reduced (P < 0.05) as compared with the untreated control (7.67 ± 0.84 log10  cfu mL(-1) ) and saline groups used with (6.57 ± 0.73 log10  cfu mL(-1) ) and without ultrasonics (6.74 ± 0.10 log10  cfu mL(-1) ). The CHX group was less effective in biofilm disruption compared to when used in combination with trypsin and proteinase K. CONCLUSION: The trypsin and CHX group with ultrasonics was significantly more effective at reducing bacterial viable counts and disrupting biofilm.

The pharmacokinetics and metabolism of meloxicam in camels after intravenous administration.

The pharmacokinetics and metabolism of meloxicam was studied in camels (Camelus dromedarus) (n = 6) following intravenous (i.v.) administration of a dose of 0.6 mg·kg/body weight. The results obtained (mean ± SD) were as follows: the terminal elimination half-life (t(1/2ß) ) was 40.2 ± 16.8 h and total body clearance (Cl(T) ) was 1.94 ± 0.66 mL·kg/h. The volume of distribution at steady state (V(SS)) was 92.8 ± 13.7 mL/kg. One metabolite of meloxicam was tentatively identified as methylhydroxy meloxicam. Meloxicam and metabolite were excreted unconjugated in urine. Meloxicam could be detected in plasma 10 days following i.v. administration in camels using a sensitive liquid chromatography tandem mass spectrometry (LC/MS/MS) method.

Household characteristics and allergen and endotoxin levels in Aleppo, Syrian Arab Republic.

Few data are available from Eastern Mediterranean countries about levels of domestic allergens and endotoxins. Dust samples were collected from mattresses and floors of 457 homes in the Syrian city of Aleppo and analysed for antigens and endotoxins. The most important predictors for detectable levels of house-dust mite allergen Der p 1 were Arabic-style houses (OR 3.21) and newer houses (OR 1.56). In homes without cats, rubber mattresses were associated with detectable cat allergen Fel d 1 in mattress dust (OR 1.6). Cockroach allergen Bla g 2 was significantly more likely to be detected in houses over 20 years old than newer houses. Endotoxin levels were significantly higher in wool/cotton mattresses and older houses.

Household characteristics and allergen and endotoxin levels in Aleppo, Syrian Arab Republic

Few data are available from Eastern Mediterranean countries about levels of domestic allergens and endotoxins. Dust samples were collected from mattresses and floors of 457 homes in the Syrian city of Aleppo and analysed for antigens and endotoxins. The most important predictors for detectable levels of house-dust mite allergen Der p 1 were Arabic-style houses [OR 3.21] and newer houses [OR 1.56]. In homes without cats, rubber mattresses were associated with detectable cat allergen Fel d 1 in mattress dust [OR 1.6]. Cockroach allergen Bla g 2 was significantly more likely to be detected in houses over 20 years old than newer houses. Endotoxin levels were significantly higher in wool/cotton mattresses and older houses

Raf kinase inhibitor protein: mechanism of loss of expression and association with genomic instability.

AIMS: Raf kinase inhibitory protein (RKIP; also known as PEBP, for phosphatidylethanolamine-binding protein) is an endogenous inhibitor of the Raf- MAPK kinase (MEK)-MAP kinase pathway. It has emerged as a significant metastasis suppressor in a variety of human cancers including colorectal cancer (CRC) and was recently shown to regulate the spindle checkpoint in cultured cells. This study aims at correlating RKIP expression with chromosomal instability in colorectal cancer samples and identifies possible mechanisms of RKIP loss. METHODS: Chromosomal instability was assessed using metaphase-based comparative genomic hybridisation (CGH) and loss of heterozygosity (LOH) in 65 cases with microsatellite stable CRC and correlated with RKIP expression. Methyl-specific PCR was used on DNA extracted from 82 cases with CRC to determine CpG methylation status at the RKIP promoter and the results correlated with RKIP protein expression. RESULTS: We demonstrate for the first time that in microsatellite stable (MSS) CRC, the number of chromosomal losses is inversely proportional to RKIP expression levels. We also show that methylation of the RKIP promoter is a major mechanism by which RKIP expression is silenced in CRC. CONCLUSIONS: RKIP loss by hypermethylation of its promoter could have a significant influence on colorectal cancer aneuploidy, which might explain its association with metastatic progression.

The effect of local doxycycline with and without tricalcium phosphate on the regenerative healing potential of periodontal osseous defects in dogs.

The purpose of this study was to evaluate the clinical and histological effects of high concentration doxycycline on osseous regeneration in adult beagle dogs. Four 5 mm two-wall periodontal osseous defects were created in the premolar and molar area of each quadrant yielding a total of 48 defects in the three dogs. Ligature-induced periodontitis was maintained for 6 weeks. Two weeks following ligature removal, one of the following graft procedures was randomly assigned to each defect: 1) doxycycline alone (DOX); 2) tricalcium phosphate alone (TCP); 3) a combined graft of DOX plus TCP, or 4), surgically debrided control. All areas received thorough scaling and root planing at the time of surgery. Clinical parameters evaluated at 4, 12, and 20 weeks after the surgical treatment included the gingival index and probing depths. Crevicular fluid was examined at 3, 10, and 28 days postoperatively for tetracycline fluorescence. Direct clinical measurements from the CEJ to a notch placed at the base of the defect and from the CEJ to the alveolar crest were made at the time of surgical treatment and reentry. The reentry procedures were performed at 4, 12, and 20 weeks postoperatively. Immediately following reentry block sections were obtained from each quadrant and prepared for examination with the light microscope. The gingival index and probing depth measurements showed greater improvement in the DOX and DOX + TCP groups. Increased regeneration (new bone, cementum, and periodontal ligament) and reduced alveolar crest resorption were observed more frequently in DOX and DOX + TCP defects, while healing by long junctional epithelium was more common in defects not treated with doxycycline.(ABSTRACT TRUNCATED AT 250 WORDS)