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Important Reservoir (important + reservoir)
Selected AbstractsEfficacy of a live equine herpesvirus-1 (EHV-1) strain C147 vaccine in foals with maternally-derived antibody: protection against EHV-1 infectionEQUINE VETERINARY JOURNAL, Issue 5 2004J. R. PATEL Summary Reasons for performing study: Currently, there is no recommended immunoprophylaxis against febrile respiratory diseases due to equine herpesvirus-1 (EHV-1) and -4 (EHV-4) in horses below age 5,6 months. This is because of interference by maternally-derived antibody (MDA) of vaccines. Objective: Unweaned equine foals are an important reservoir of EHV-1 transmission; therefore, we experimentally assessed the efficacy of a live EHV-1 vaccine in foals age 1.4-3.5 months with MDA. Methods: Following vaccination and challenge, parameters assessed were virus shedding in nasal mucus, leucocyte-associated viraemia, circulating virus neutralising antibody activity and clinical reactions. Results: Controlled challenge showed that a single intranasal dose of the vaccine afforded partial but significant protection against febrile respiratory disease, virus shedding and viraemia due to EHV-1 infection, despite virus-neutralising MDA. Conclusions and potential relevance: The prospective vaccine would be a significant step forward in reducing the incidence of the disease caused by EHV-1 infection. [source] Wild boar as an important reservoir of hepatitis E virus in western JapanHEPATOLOGY RESEARCH, Issue 3 2007Koji Yano No abstract is available for this article. [source] Diversity of canopy and understorey spiders in north-temperate hardwood forestsAGRICULTURAL AND FOREST ENTOMOLOGY, Issue 2 2009Maxim Larrivée Abstract 1,We characterized and compared diversity patterns of canopy and understorey spiders (Arachnida: Araneae) on sugar maple (Acer saccharum Marsh.) and American beech (Fagus grandifolia Ehrh.) in hardwood forests of southern Québec, Canada. 2,We sampled canopies of 45 sugar maple and 45 American beech trees and associated understorey saplings in mature protected forests near Montréal. Samples were obtained by beating the crown foliage at various heights and by beating saplings around each tree. 3,Eighty-two species were identified from 13 669 individuals. Forty-eight species and 3860 individuals and 72 species and 9809 individuals were collected from the canopy and the understorey, respectively. 4,Multivariate analyses (NMDS ordination and NPMANOVA) showed the composition of canopy and understorey assemblages differed significantly, and canopy assemblages differed between tree species. Rank-abundance distribution models fitted to the canopy and understorey data indicated that different mechanisms structure the assemblages in both habitats. Three abundant spider species were significantly more common in the canopy; ten species were collected significantly more often in the understorey. 5,The forest canopy was shown to be an important reservoir for spider diversity in north-temperate forests. [source] A long-term study of non-native-heartworm transmission among coyotes in a Mediterranean ecosystemOIKOS, Issue 3 2003Benjamin N. Sacks In Mediterranean ecosystems, abiotic factors are known to affect vertebrate population dynamics, but little is known about how these factors affect population dynamics of parasites. We conducted a 9-year investigation of the roles of temperature, precipitation, and vector abundance as determinants of transmission of the non-native canine heartworm (Dirofilaria immitis), a dangerous parasite of pets, among coyotes (Canis latrans), an important reservoir, in north-coastal California. Dates of heartworm transmission and total annual transmission were determined, respectively, from lengths and numbers of heartworms found in known-age coyotes. Vector host-seeking activity was assessed through weekly mosquito trapping. Within years, heartworm transmission occurred only when cumulative temperatures were sufficient to allow larval heartworms to develop to the infective stage (as predicted by an existing degree-day model), and when suitable vectors were available. Most (95%) heartworms infected their hosts between 1 July and 14 September. The onset of transmission periods always occurred after the peak in vector host-seeking activity and varied annually. Transmission periods ended before temperatures became limiting due to absence of vectors. The timing of host-seeking activity of the primary vector species, Ochlerotatus sierrensis, also was correlated with the onset of warming temperatures such that parasite and vector phenology were synchronized. For this reason (partly), the variation in timing of seasonal warming had no detectable effect on total annual transmission. Abundance of host-seeking Oc. sierrensis was positively correlated with annual precipitation, and annual heartworm transmission was positively correlated with abundance of host-seeking Oc. sierrensis. Annual transmission also was positively correlated with abundance of a less numerous vector species, Anopheles punctipennis, and was directly correlated with precipitation. This study demonstrates that multiannual variability in temperature, which affects seasonality of transmission, has little effect on annual transmission, but that precipitation is a driving force determining annual transmission. These findings imply that in California, and possibly other Mediterranean climate zones, it is especially important to preventively treat pets in summers following high-rainfall winters. [source] Clinical and molecular epidemiology of community-acquired, healthcare-associated and nosocomial methicillin-resistant Staphylococus aureus in SpainCLINICAL MICROBIOLOGY AND INFECTION, Issue 12 2009J. Rodríguez-Baño Abstract A prospective cohort study including all new cases of methicillin-resistant Staphylococcus aureus (MRSA) colonization or infection in 64 Spanish hospitals during June 2003 was performed to investigate the epidemiology of MRSA in Spain. Only patients who yielded clinical MRSA-positive samples were included. Epidemiological and clinical data for a total of 370 cases were collected. Genotyping was performed using pulsed-field gel electrophoresis and multilocus sequence typing. Panton,Valentine leukocidin genes and the staphylococcal chromosomal cassette mec (SCCmec) were identified in representative isolates. MRSA was considered to be nosocomially acquired in 202 cases (55%), healthcare-associated (HCA) in 139 cases (38%), community-acquired (CA) in three cases, and of uncertain mode of acquisition in 26 (7%) cases. The pooled population-based rate was 2.31 cases/100 000 population/month, and the pooled nosocomial rate was 0.21 cases/1000 hospital stays (20.2% of S. aureus). Peripheral vascular disease, respiratory tract infections, catheter infections, bloodstream infections and crude mortality were more frequent among HCA cases, whereas neoplasia and urinary tract infections were more frequent among nosocomially acquired cases. Two clones related to the paediatric clone ST5-IV accounted for 71% of the isolates; EMRSA-16 has emerged in two different geographical areas. Only one isolate belonged to the formerly predominant Iberian clone. The three CA isolates were related to the USA300 clone. SCCmec type IV was the most frequent type in nosocomial and HCA isolates. The epidemiology of MRSA has changed in Spain; outpatients with previous healthcare contact represent a very important reservoir of MRSA, and community isolates are emerging. [source] Variability of tilapias (Oreochromis spp.) introduced in Mexico: morphometric, meristic and genetic charactersJOURNAL OF APPLIED ICHTHYOLOGY, Issue 1 2004I. D. L. A. Barriga-Sosa Summary In Mexico, the tilapia Oreochromis provides one of the most important sources of animal protein and income in a wide variety of communities throughout the country, however, their culture and production face severe problems because of lack of management information. Evaluated in the present study is the degree of morphological, meristic and allozyme variation of two tilapia strains, two species and one hybrid from two important reservoirs in Mexico, two tilapia fry production farms (TFPF) and an experimental production system (EPS), to diagnose the actual status and degree of variation among them. Twenty-two presumptive loci were utilized to determine the genetic variation, structuring and distances among samples. Multivariate analyses of 11 meristic and 33 morphometric characters were also evaluated, including the distance from the end of the mouth opening to the most anterior dorsal fin (0.9894), distance from the anal fin base to the anterior part of the caudal fin (0.9845) and the base length of the dorsal fin (0.9839) which contributed to the separation of groups. The canonical discriminant functions for the morphometric and meristic variables show that the correct classification of the organisms in percentages and in the sites of origin was on average 72%. The tilapia from the reservoirs and the experimental production system had higher genetic variations than tilapia from the fry production farms (average He 0.310, 0.062, 0.151 for Metztitlan, Infiernillo and EPS, respectively, vs 0.024 and 0.000 for Los Amates and Zacatepec, respectively). The genetic data indicate that fishes of the TFPF should be monitored closely, as they are the main source of dispersion to the reservoirs. Present results show that these data could be a fast and reliable aid to the fisheries and management of tilapia in Mexico. [source] Prevalence of human papillomaviruses in urine samples of male patients infected with HIV-1 in Sao Paulo, Brazil,JOURNAL OF MEDICAL VIROLOGY, Issue 12 2009Fernando A.M. Costa Abstract Human papillomavirus is a DNA virus that includes 118 genotypes. HPV16 is responsible for 80% of cervical cancer in women. Men are important reservoirs and major transmitters of HPV to their partners. The aim of this study was to detect HPV DNA and to determine the prevalence of HPV types 6, 11, 16, and 18 in urine samples of men infected with HIV-1. This study included 223 patients infected with HIV-1 from the Center of Reference on HIV/AIDS (CRT-SP) and an outpatient clinic of HIV. Urine samples were collected and after DNA extraction real-time PCR was performed for detection of HPV DNA. Positive samples were then tested by conventional PCR using type-specific primers for the four HPV types. A total of 223 men infected with HIV-1 were tested, 81% of whom were on HAART. Four (5.8%) were positive for HPV6, 18 (26.1%) were positive for HPV11, 22 (31.9%) were positive for HPV16 and five (7.2%) were positive for HPV18 by conventional PCR. Twenty (29%) patients had other HPV types and five patients (1.5%) had multiple types. The mean T CD4+cells count was 517 and 441,cells/mm3 (P,=,0.30), in HPV negative and positive men, respectively. The HIV viral load was higher in the HPV negative group than for in the men with HPV (P,=,0.0002). A 30.9% prevalence of HPV was found in asymptomatic urine samples of men infected with HIV-1. This study suggests that urine may be a useful specimen for HPV screening. J. Med. Virol. 81:2007,2011, 2009. © 2009 Wiley-Liss, Inc. [source] THE VENEZUELAN HYDROCARBON HABITAT, PART 2: HYDROCARBON OCCURRENCES AND GENERATED-ACCUMULATED VOLUMESJOURNAL OF PETROLEUM GEOLOGY, Issue 2 2000K. H. James Venezuela's most important hydrocarbon reserves occur in the intermontane Maracaibo Basin and in the Eastern Venezuela foreland basin. Seeps are abundant in these areas. Lesser volumes occur in the Barinas-Apure foreland basin. Most of the oil in these basins was derived from the Upper Cretaceous La Luna Formation in the west and its equivalent, the Querecual Formation, in the east. Minor volumes of oil derived from Tertiary source rocks occur in the Maracaibo and Eastern Venezuela Basins and in the Falcdn area. Offshore, several TCF of methane with some associated condensate are present in the Cadpano Basin, and gas is also present in the Columbus Basin. Oil reserves are present in La Vela Bay and in the Gulf of Paria, and oil has been encountered in the Cariaco Basin. The Gulf of Venezuela remains undrilled. The basins between the Netherlands and Venezuelan Antillian Islands seem to lack reservoirs. Tertiary sandstones provide the most important reservoirs, but production comes also from fractured basement (igneous and metamorphic rocks), from basal Cretaceous sandstones and from fractured Cretaceous limestones. Seals are provided by encasing shales, unconformities, faults and tar plugs. There is a wide variety of structural and stratigraphic traps. The Orinoco Heavy Oil Belt of the Eastern Venezuela Basin, one of the world's largest accumulations (1.2 times 1012 brl) involves stratigraphic trapping provided by onlap and by tar plugging. Stratigraphic trapping involving unconformities and tar plugging also plays a major role also in the Bolivar Coastal complex of fields along the NE margin of Lake Maracaibo. Many of the traps elsewhere in the Maracaibo Basin were influenced by faulting. The faults played an extensional role during Jurassic rifting and subsequently suffered inversion and strike-slip reactivation. This created anticlines as well as fracture porosity and permeability, and influenced the distribution of sandstone reservoirs, unconformities and related truncation traps. The faults probably also provided migration paths as well as lateral seals. This is very likely the case also in the large, thrust-related traps of the Furrial Trend in Eastern Venezuela. Normal faults, many antithetic to basement dip, provide important traps in the Las Mercedes, Oficina and Emblador complexes on the southern flanks of the Eastern Venezuela Basin. Similar faults seem to control the Sinco-Silvestre complex of the Barinas-Apure Basin. Much of VenezuelaS crude (around 1.5 trillion brls original STOIIP) has been degraded and is heavy, Perhaps two to three trillion brls of precursor, lighter oil existed. While the known Upper Cretaceous La Luna and Querecual Formations are known to include prolific source rocks, a reasonable generation/accumulation efficiency of 10% implies volumes too large to have come from the reported kitchens. The country's vast reserves are perhaps better explained by recognizing that the present-day basins are remnants of much broader sedimentary areas. The source rocks originally had a much more regional distribution. They suffered widespread, earlier phases of generation that probably charged early-formed traps on a regional scale. These, together with more recent kitchens, provided oil to the present-day accumulations. This history involved long-distance migration and remigration. [source] Simultaneous PCR Detection of the Two Major Bacterial Pathogens of GeraniumJOURNAL OF PHYTOPATHOLOGY, Issue 2 2002D. L. GLICK Xanthomonas campestris pv. pelargonii (Xcp) and Ralstonia solanacearum (Rs) are the two most important bacterial pathogens of commercially cultivated geraniums (Pelargonium spp.), both causing bacterial wilt and leaf spot. Asymptomatic infections are important reservoirs of infections in commercial growing facilities. Our objective was to design a multiplex PCR (Polymerase Chain Reaction) assay to detect infection by either or both of these pathogens. We used a previously characterized PCR primer pair for Xcp that amplifies a region of 200 bp. In addition, we designed a new primer pair specific for Rs that amplifies a region of 822 bp. With these two primer pairs, we could detect either or both pathogens. As geranium tissue extracts frequently contain inhibitors of the PCR process, a negative PCR could result from either an accurate indication that the plant was pathogen-free or from a false negative assay. We therefore designed `amplification competence' primers, targeting a portion of the geranium 18 s rRNA gene, and generating a 494-bp amplification product that confirms amplification competence and validates a negative assay result. Thus, the triple primer pair multiplex PCR screens for the two most important bacterial pathogens of geraniums simultaneously confirms amplification competence for each geranium sample. [source] Indigenous domestic breeds as reservoirs of genetic diversity: the Argentinean Creole cattleANIMAL GENETICS, Issue 5 2001G. Giovambattista Contrary to highly selected commercial breeds, indigenous domestic breeds are composed of semi-wild or feral populations subjected to reduced levels of artificial selection. As a consequence, many of these breeds have become locally adapted to a wide range of environments, showing high levels of phenotypic variability and increased fitness under natural conditions. Genetic analyses of three loci associated with milk production (,S1 -casein, , -casein and prolactin) and the locus BoLA-DRB3 of the major histocompatibility complex indicated that the Argentinean Creole cattle (ACC), an indigenous breed from South America, maintains high levels of genetic diversity and population structure. In contrast to the commercial Holstein breed, the ACC showed considerable variation in heterozygosity (He) and allelic diversity (A) across populations. As expected, bi-allelic markers showed extensive variation in He whereas the highly polymorphic BoLA-DRB3 showed substantial variation in A, with individual populations having 39,74% of the total number of alleles characterized for the breed. An analysis of molecular variance (AMOVA) of nine populations throughout the distribution range of the ACC revealed that 91.9,94.7% of the total observed variance was explained by differences within populations whereas 5.3,8.1% was the result of differences among populations. In addition, the ACC breed consistently showed higher levels of genetic differentiation among populations than Holstein. Results from this study emphasize the importance of population genetic structure within domestic breeds as an essential component of genetic diversity and suggest that indigenous breeds may be considered important reservoirs of genetic diversity for commercial domestic species. [source] | ||||||||||||||||