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High Endemicity (high + endemicity)
Selected AbstractsBiodiversity hotspots, centres of endemicity, and the conservation of coral reefsECOLOGY LETTERS, Issue 6 2002Terry P. Hughes Abstract On land, biodiversity hotspots typically arise from concentrations of small-range endemics. For Indo-Pacific corals and reef fishes, however, centres of high species richness and centres of high endemicity are not concordant. Moreover ranges are not, on average, smaller inside the Central Indo-Pacific (CI-P) biodiversity hotspot. The disparity between richness and endemicity arises because corals and reef fishes have strongly skewed range distributions, with many species being very widespread. Consequently, the largest ranges overlap to generate peaks in species richness near the equator and the CI-P biodiversity hotspot, with only minor contributions from endemics. Furthermore, we find no relationship between the number of coral vs. fish endemics at locations throughout the Indo-Pacific, even though total richness of the two groups is strongly correlated. The spatial separation of centres of endemicity and biodiversity hotspots in these taxa calls for a two-pronged management strategy to address conservation needs. [source] Hepatitis in Albanian children: Molecular analysis of hepatitis A virus isolatesJOURNAL OF MEDICAL VIROLOGY, Issue 4 2004Rosanna Gabrieli Abstract Hepatitis A is a common disease in developing countries and Albania has a high prevalence of this disease associated to young age. In spite of the occurrence of a unique serotype there are different genotypes classified from I to VII. Genotype characterisation of HAV isolates circulating in Albania has been undertaken, as well as the study of the occurrence of antigenic variants in the proteins VP3 and VP1. To evaluate the genetic variability of the Albanian hepatitis A virus (HAV) isolates, samples were collected from 12 different cities, and the VP1/2A junction amplified and sequenced. These sequences were aligned and a phylogenetic analysis performed. Additionally, the amino half sequence of the protein VP3 and the complete sequence of the VP1 was determined. Anti-HAV IgM were present in 66.2% of all the sera. Fifty HAV isolates were amplified and the analysis revealed that all the isolates were sub-genotype IA with only limited mutations. When the deduced amino acid sequences were obtained, the alignment showed only two amino acids substitutions at positions 22 and 34 of the 2A protein. A higher genomic stability of the VP1/2A region, in contrast with what occurs in other parts of the world could be observed, indicating high endemicity of HAV in Albania. In addition, two potential antigenic variants were detected. The first at position 46 of VP3 in seven isolates and the second at position 23 of VP1 in six isolates. J. Med. Virol. 72:533,537, 2004. © 2004 Wiley-Liss, Inc. [source] Hepatitis A and B vaccination and public healthJOURNAL OF VIRAL HEPATITIS, Issue 2007F. Blaine Hollinger Summary., The introduction and implementation of hepatitis B vaccination programmes in areas of high endemicity has been very stressful. However, this initial accomplishment has led to the reassessment of priorities in some countries which could undermine these early successes. Work still remains to be done to support and implement interventions that will bring us closer to the WHO goal and to the control of hepatitis B in the community at large. Hepatitis A vaccine strategy for immunizing toddlers is shifting to those countries with intermediate endemicity where increasing morbidity in adults is being observed. Accumulating evidence indicates that such programmes can result in impressive reductions in the incidence of hepatitis A by herd immunity. Monitoring of these populations to determine durability of protection will be important to avoid shifting the infection to the older age population, when symptoms are more likely to occur. National policies need to consider hepatitis A vaccination in the context of other public health priorities. [source] Diversification within glacial refugia: tempo and mode of evolution of the polytypic fish Barbus sclateriMOLECULAR ECOLOGY, Issue 15 2009HUGO F. GANTE Abstract A diversity of evolutionary processes can be responsible for generating and maintaining biodiversity. Molecular markers were used to investigate the influence of Plio-Pleistocene climatic oscillations on the evolutionary history of taxa restricted to the freshwaters of a classical glacial refugium. Population genetic, phylogenetic and phylogeographical methods allowed the inference of temporal dynamics of cladogenesis and processes shaping present-day genetic constitution of Barbus sclateri, a polytypic taxon found in several independent river drainages in southern Iberian Peninsula. Results from different analyses consistently indicate several range expansions, high levels of allopatric fragmentation, and admixture following secondary contacts throughout its evolutionary history. Using a Bayesian demographical coalescent model on mitochondrial DNA sequences calibrated with fossil evidence, all cladogenetic events within B. sclateri are inferred to have occurred during the Pleistocene and were probably driven by environmental factors. Our results suggest that glaciation cycles did not inhibit cladogenesis and probably interacted with regional geomorphology to promote diversification. We conclude that this polytypic taxon is a species complex that recently diversified in allopatry, and that Pleistocene glaciation,deglaciation cycles probably contributed to the generation of biological diversity in a classical glacial refugium with high endemicity. [source] Comparison of an enzyme linked immunosorbent assay (ELISA) and a radioallergosorbent test (RAST) for detection of IgE antibodies to Brugia malayiPARASITE IMMUNOLOGY, Issue 11-12 2003Sitti Wahyuni SUMMARY The enzyme linked immunosorbent assay (ELISA) for specific IgE antibodies to Brugia malayi was compared with the radioallergosorbent test (RAST) for use in immunoepidemiological studies of lymphatic filariasis. Sera used were from individuals (aged 5,82 years) living in an area endemic for lymphatic filariasis in South Sulawesi, Indonesia. The percentage of positive IgE ELISA reactions (52·6%) among the population was lower than the percentage of positive RAST (94·5%). Although an overall significant concordance was found between the two assays (P < 0·001), 328 (42·7%) individuals with a positive RAST result were negative in the ELISA, whereas only 6 (0·8%) subjects were positive by ELISA, yet negative by RAST. When the population was divided into those with active infection (positive for anti-filarial IgG4) and those not infected (mf-negative and negative for anti-filarial IgG4), the correlation between the two tests was higher in the IgG4-positive (rho = 0·70) than in the IgG4-negative (rho = 0·52) group. These results indicate that in assessment of B. malayi specific IgE antibody, RAST is superior to ELISA. However, given the use of radioactivity in the RAST method and given our results obtained in subjects with high anti-filarial IgG4, one could consider using the IgE-ELISA in areas with high endemicity for filariasis. In areas with low endemicity or where control programs are implemented, sera will have to be tested by RAST. [source] National guidelines for the control and prevention of methicillin-resistant Staphylococcus aureus,what do they tell us?CLINICAL MICROBIOLOGY AND INFECTION, Issue 9 2007H. HumphreysArticle first published online: 30 JUN 200 Abstract Guidelines to control and prevent methicillin-resistant Staphylococcus aureus (MRSA) infection are available in many countries. Infection control and prevention teams determine local strategies using such national guidelines, but not all guidelines involve a rigorous assessment of the literature to determine the strength of the recommendations. Available guidelines drafted by national agencies or prominent professional organisations in Germany, New Zealand, North America, The Netherlands, Ireland and the UK were reviewed. Significant literature reviews were a component of guidelines from the UK and North America. Recommendations were not graded on the strength of the evidence in guidelines from New Zealand and The Netherlands. The Netherlands, a country with a very low prevalence of MRSA, had the simplest set of guidelines. Few of the recommendations in any of the guidelines achieved the highest grading, i.e., based on well-designed, experimental, clinical or epidemiological studies, even though the logic of the proposed measures is clear. The onset of community-acquired MRSA is reflected in the recent publication of guidelines from North America. New developments, such as rapid testing and mathematical modelling, are of importance in helping to control MRSA in settings of both low and high endemicity. National guidelines are increasingly evidence-based, although good scientific studies concerning some aspects of MRSA control are lacking. However, general principles, e.g., early detection and isolation, are recommended by all guidelines. There is still a role for consensus and the opinion of experts in devising national guidelines. [source] | |||||||||||||