Influence of irrigant needle depth in removing bioluminescent bacteria inoculated into instrumented root canals using real-time imaging in vitro

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/73506/1/j.1365-2591.2004.00906.x.pd

Marine Biodiversity in the Caribbean: Regional Estimates and Distribution Patterns

This paper provides an analysis of the distribution patterns of marine biodiversity and summarizes the major activities of the Census of Marine Life program in the Caribbean region. The coastal Caribbean region is a large marine ecosystem (LME) characterized by coral reefs, mangroves, and seagrasses, but including other environments, such as sandy beaches and rocky shores. These tropical ecosystems incorporate a high diversity of associated flora and fauna, and the nations that border the Caribbean collectively encompass a major global marine biodiversity hot spot. We analyze the state of knowledge of marine biodiversity based on the geographic distribution of georeferenced species records and regional taxonomic lists. A total of 12,046 marine species are reported in this paper for the Caribbean region. These include representatives from 31 animal phyla, two plant phyla, one group of Chromista, and three groups of Protoctista. Sampling effort has been greatest in shallow, nearshore waters, where there is relatively good coverage of species records; offshore and deep environments have been less studied. Additionally, we found that the currently accepted classification of marine ecoregions of the Caribbean did not apply for the benthic distributions of five relatively well known taxonomic groups. Coastal species richness tends to concentrate along the Antillean arc (Cuba to the southernmost Antilles) and the northern coast of South America (Venezuela – Colombia), while no pattern can be observed in the deep sea with the available data. Several factors make it impossible to determine the extent to which these distribution patterns accurately reflect the true situation for marine biodiversity in general: (1) highly localized concentrations of collecting effort and a lack of collecting in many areas and ecosystems, (2) high variability among collecting methods, (3) limited taxonomic expertise for many groups, and (4) differing levels of activity in the study of different taxa

PREVALENCE OF FLUOROQUINOLONE RESISTANCE IN EUROPE

Since 1984, when the first fluoroquinolone, norfloxacin, was marketed in Europe, there has been a marked increase in the usage of this class of drugs. In order to evaluate the influence of this drug usage on the prevalence of resistance to fluoroquinolones in clinical isolates of the family Enterobacteriaceae, Pseudomonas aeruginosa, Staphylococcuss aureus, coagulase-negative staphylococci and Enterococcus faecalis we reviewed the susceptibility data from four collaborative surveys conducted between 1983 and 1990 by the Study Group ‘Bacterial Resistance’ of the Paul-Ehrlich-Society for Chemotherapy. All participating laboratories used the same standardized methods. Miminal inhibitory concentrations were determined by the broth microdilution method. More than 20,000 bacterial strains were tested. The results are presented for ciprofloxacin, which is regarded as the representative of the fluoroquinolones. Using greater than or equal to 4 mg/l as a breakpoint for resistance to ciprofloxacin, the prevalence of resistant strains of the family Enterobacteriaceae in Central Europe between 1983 and 1990 remained below 1%. In contrast, the resistance rates in P. aeruginosa were 0.7%, 1.0%, 3.8% and 7.0%, in S. aureus 0%, 0.5%, 6.6% and 6.8%, and in E. faecalis 2.2%, 0.7%, 4.9% and 7.7% in 1983, 1986, 1989 and 1990, respectively. The latest study carried out in cooperation with 78 laboratories from 12 European countries revealed great differences in the prevalence of resistance to fluoroquinolones from one species to another ranging from 0% with Proteus vulgaris and Salmonella spp. to 26.7% with Providencia stuartii. The highest rates of resistance were recorded for oxacillin-resistant strains of S. aureus (70.6%) and oxacillin-resistant coagulase-negative staphylococci (51.2%). Resistance levels for individual species varied between countries, but they were consistently higher in Southern Europe than in Northwest and Central Europe. Resistance in S. aureus and E. faecalis was more prevalent in isolates from intensive care patients than in isolates from patients on normal wards. In addition, S. aureus isolates displayed a considerable difference in the resistance rates for blood (9.3%) and urine (34.4%)