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101.
Ruiz-Moreno D Willis BL Page AC Weil E Cróquer A Vargas-Angel B Jordan-Garza AG Jordán-Dahlgren E Raymundo L Harvell CD 《Diseases of aquatic organisms》2012,100(3):249-261
Coral diseases are taking an increasing toll on coral reef structure and biodiversity and are important indicators of declining health in the oceans. We implemented standardized coral disease surveys to pinpoint hotspots of coral disease, reveal vulnerable coral families and test hypotheses about climate drivers from 39 locations worldwide. We analyzed a 3 yr study of coral disease prevalence to identify links between disease and a range of covariates, including thermal anomalies (from satellite data), location and coral cover, using a Generalized Linear Mixed Model. Prevalence of unhealthy corals, i.e. those with signs of known diseases or with other signs of compromised health, exceeded 10% on many reefs and ranged to over 50% on some. Disease prevalence exceeded 10% on 20% of Caribbean reefs and 2.7% of Pacific reefs surveyed. Within the same coral families across oceans, prevalence of unhealthy colonies was higher and some diseases were more common at sites in the Caribbean than those in the Pacific. The effects of high disease prevalence are potentially extensive given that the most affected coral families, the acroporids, faviids and siderastreids, are among the major reef-builders at these sites. The poritids and agaricids stood out in the Caribbean as being the most resistant to disease, even though these families were abundant in our surveys. Regional warm temperature anomalies were strongly correlated with high disease prevalence. The levels of disease reported here will provide a much-needed local reference point against which to compare future change. 相似文献
102.
Ann F. Budd Flavia L. D. Nunes Ernesto Weil John M. Pandolfi 《Evolutionary ecology》2012,26(2):265-290
Recent advances in morphometrics and genetics have led to the discovery of numerous cryptic species in coral reef ecosystems.
A prime example is the Montastraea annularis scleractinian coral species complex, in which morphological, genetic, and reproductive data concur on species boundaries,
allowing evaluation of long-term patterns of speciation and evolutionary innovation. Here we test for cryptic species in the
Atlantic species, Montastraea cavernosa, long recognized as polymorphic. Our modern samples consist of 94 colonies collected at four locations (Belize, Panamá, Puerto
Rico in the Caribbean; S?o Tomé in the Eastern Atlantic). Our fossil samples consist of 78 colonies from the Plio-Pleistocene
of Costa Rica and Panamá. Landmark morphometric data were collected on thin sections of 46 modern and 78 fossil colonies.
Mahalanobis distances between colonies were calculated using Bookstein coordinates, revealing two modern and four fossil morphotypes.
The remaining 48 of the 94 modern colonies were assigned to morphotype using discriminant analysis of calical measurements.
Cross-tabulation and multiple comparisons tests show no significant morphological differences among geographic locations or
water depths. Patterns of variation within and among fossil morphotypes are similar to modern morphotypes. DNA sequence data
were collected for two polymorphic nuclear loci (β-tub1 and β-tub2) on all 94 modern colonies. Haplotype networks show that both genes consist of two clades, but morphotypes are not associated
with genetic clades. Genotype frequencies and two-locus genotype assignments indicate genetic exchange across clades, and
ϕst values show no genetic differentiation between morphotypes at different locations. Taken together, our morphological and
genetic results do not provide evidence for cryptic species in M. cavernosa, but indicate instead that this species has an unusually high degree of polymorphism over a wide geographic area and persisting
for >25 million years (myr). 相似文献
103.
Meike Hermes Sandra Weil Ariane Groth Ralf Dressel Joachim Koch Lutz Walter 《Immunogenetics》2012,64(11):845-848
Killer immunoglobulin-like receptors (KIRs) represent a highly polymorphic and diverse gene family in rhesus macaques. Analyses of the respective gene products have been hampered until now due to non-availability of specific monoclonal antibodies and failure of cross-reactivity of anti-human KIR antibodies. We utilised one activating (KIR3DSW08) and two inhibitory (KIR3DLW03 and KIR3DL05) rhesus macaque KIR-Fc fusion proteins for generation of monoclonal antibodies in mice. Besides broadly reacting ones, we obtained anti-rhesus macaque KIR antibodies with intermediate and with single specificity. These monoclonal antibodies were tested for binding to a panel of rhesus macaque KIR proteins after heterologous expression on transiently transfected cells. Epitope mapping identified two polymorphic regions that are located next to each other in the mature KIR proteins. The availability of monoclonal antibodies against rhesus macaque KIR proteins will enable future studies on KIR at the protein level in rhesus macaques as important animal models of human infectious diseases. 相似文献
104.
Foster NL Paris CB Kool JT Baums IB Stevens JR Sanchez JA Bastidas C Agudelo C Bush P Day O Ferrari R Gonzalez P Gore S Guppy R McCartney MA McCoy C Mendes J Srinivasan A Steiner S Vermeij MJ Weil E Mumby PJ 《Molecular ecology》2012,21(5):1143-1157
Understanding patterns of connectivity among populations of marine organisms is essential for the development of realistic, spatially explicit models of population dynamics. Two approaches, empirical genetic patterns and oceanographic dispersal modelling, have been used to estimate levels of evolutionary connectivity among marine populations but rarely have their potentially complementary insights been combined. Here, a spatially realistic Lagrangian model of larval dispersal and a theoretical genetic model are integrated with the most extensive study of gene flow in a Caribbean marine organism. The 871 genets collected from 26 sites spread over the wider Caribbean subsampled 45.8% of the 1900 potential unique genets in the model. At a coarse scale, significant consensus between modelled estimates of genetic structure and empirical genetic data for populations of the reef-building coral Montastraea annularis is observed. However, modelled and empirical data differ in their estimates of connectivity among northern Mesoamerican reefs indicating that processes other than dispersal may dominate here. Further, the geographic location and porosity of the previously described east-west barrier to gene flow in the Caribbean is refined. A multi-prong approach, integrating genetic data and spatially realistic models of larval dispersal and genetic projection, provides complementary insights into the processes underpinning population connectivity in marine invertebrates on evolutionary timescales. 相似文献
105.
106.
S Chen AJ de Craen Y Raz E Derhovanessian AC Vossen WG Rudi G Pawelec AB Maier 《Immunity & ageing : I & A》2012,9(1):18-7
ABSTRACT: BACKGROUND: Cytomegalovirus (CMV) infection has been reported to contribute to the pathogenesis of type 1 diabetes and post-transplantation diabetes. However, CMV infection has not been evaluated as a possible risk factor for type 2 diabetes. Our aim was to investigate potential associations between CMV seropositivity, CMV IgG antibody level and glucose regulation in the oldest old. RESULTS: CMV seropositive subjects were more likely to have type 2 diabetes (17.2% vs 7.9%, p = 0.016), had a higher level of HbA1c (p = 0.014) and higher non-fasting glucose (p = 0.024) in the oldest olds. These associations remained significant after adjustment for possible confounders. CMV IgG antibody level was not significantly associated with glucose regulation (all p > 0.05). CONCLUSIONS: In the oldest old, CMV seropositivity is significantly associated with various indicators of glucose regulation. This finding suggests that CMV infection might be a risk factor for the development of type 2 diabetes in the elderly. 相似文献
107.
Genetic characterization of field isolates and clinical specimens of filarial nematodes is often limited by a shortage of DNA; therefore, we evaluated a multiple displacement amplification (MDA) based whole genome amplification method. The quality of amplified DNA was examined by conventional PCR, real-time PCR, and DNA hybridization. MDA of 5.0 ng of adult Brugia malayi DNA and one-fifteenth of the DNA isolated from a single microfilaria resulted in 6.3 and 4.2 μg of amplified DNA, respectively. Amplified DNA was equivalent to native genomic DNA for hybridization to B. malayi BAC library clones or to an oligonucleotide microarray with approximately 18,000 filarial DNA sequences. MDA is useful for whole genome amplification of filarial DNA from very small amounts of starting material. This technology will permit detailed studies of genetic diversity that were not previously feasible. 相似文献
108.
Cardiopulmonary resuscitation in the mouse. 总被引:4,自引:0,他引:4
Lei Song Max Harry Weil Wanchun Tang Shijie Sun Tommaso Pellis 《Journal of applied physiology》2002,93(4):1222-1226
We sought to develop a model of cardiac arrest and resuscitation on mice that would be comparable to that of large mammals and would allow for more fundamental investigations on cardiopulmonary arrest and cardiac resuscitation. A model of cardiopulmonary resuscitation previously developed by our group on rats was adapted to anesthetized, mechanically ventilated adult male Institute of Cancer Research mice that weighed 46 +/- 3 g. The trachea was intubated through the mouth, and end-tidal PCO(2) (PET(CO(2))) was measured with a microcapnometer. Catheters were advanced into the aorta and into the right atrium, and coronary perfusion pressure (CPP) was computed. A 1.5-mA alternating current was delivered to the right ventricular endocardium, which produced ventricular fibrillation or a pulseless rhythm. Precordial compression was begun 4 min later. Ten sequential studies were performed, during which five animals were successfully resuscitated and five failed resuscitation efforts. Successful resuscitation was contingent on the restoration of threshold levels of CPP and PET(CO(2)) during chest compression. As in rats, swine, and human patients, threshold levels of mean aortic pressure, CPP, and PET(CO(2)) were critical determinates of resuscitability in this murine model of threshold level of cardiac arrest and resuscitation. 相似文献
109.
We have isolated mutants of Escherichia coli which severely reduce the growth of bacteriophage lambda carrying the b221 deletion. Some of the bacterial strains also cause a moderate reduction in the growth of wild-type phage. In the mutant hosts tested, the growth of λb221 is restored by chromosomal alterations producing a non-specific increase in genome length. Thus the defect in growth can be attributed to the physical size of the genome, rather than a genetic effect of the b221 deletion. Our experiments show that the failure to grow results from a block to head morphogenesis and that growth can be restored by mutations in at least two phage head genes. In the accompanying paper we have shown that even in the normal bacterium, the process of packing and cutting the λb221 genome is perturbed as a result of its small size. The block to morphogenesis in the bacterial mutant we have studied most extensively appears to result from an enhancement of the same effect. The experiments described support the hypothesis that there is host participation in the cutting of encapsulated lambda DNA, although it is not yet clear if this involves the direct participation of a host gene product. 相似文献
110.
J.H. Weil 《Biochimie》1973,55(1):XI-XII