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41.
T. C. L. Bridge K. E. Fabricius P. Bongaerts C. C. Wallace P. R. Muir T. J. Done J. M. Webster 《Coral reefs (Online)》2012,31(1):179-189
Mesophotic coral reefs in the Indo-West Pacific, the most diverse coral reef region on earth, are among the least documented.
This study provides the first detailed investigation of the diversity of Scleractinia and Octocorallia of the mesophotic Great
Barrier Reef (GBR). Specimens were collected by 100-m rock dredge tows at 47–163 m depth on 23 sites in four regions (15.3°–19.7°
latitude South). Twenty-nine hard coral species from 19 families were recorded, with the greatest diversity found at <60 m
depth, and no specimen was found >102 m. Many of these species are also commonly observed at shallower depths, particularly
in inshore areas. Twenty-seven octocoral genera were collected, 25 of which represented azooxanthellate genera. Generic richness
of octocorals was highest at depths >60 m. Sixteen of the 25 azooxanthellate genera were either absent or very rare at <18 m,
and only five azooxanthellate genera were common on both shallow and mesophotic reefs. Species-area models indicated that
the total diversity of hard corals on the deep mesophotic reefs sampled during this study was ~84 species while octocorals
were represented by ~37 genera; however, the wide 95% confidence limits indicates that more intensive sampling effort is required
to improve the accuracy of these estimates. Nonetheless, these results show that the taxonomic richness, particularly of hard
corals, on mesophotic reefs may be much higher than previously thought, a finding that has implications for the comprehensive
and adequate protection of the full range of biodiversity of the GBR. 相似文献
42.
Aim
Coral reef communities occurring in deeper waters have received little research effort compared to their shallow-water counterparts, and even such basic information as their location and extent are currently unknown throughout most of the world. Using the Great Barrier Reef as a case study, habitat suitability modelling is used to predict the distribution of deep-water coral reef communities on the Great Barrier Reef, Australia. We test the effectiveness of a range of geophysical and environmental variables for predicting the location of deep-water coral reef communities on the Great Barrier Reef.Location
Great Barrier Reef, Australia.Methods
Maximum entropy modelling is used to identify the spatial extent of two broad communities of habitat-forming megabenthos phototrophs and heterotrophs. Models were generated using combinations of geophysical substrate properties derived from multibeam bathymetry and environmental data derived from Bio-ORACLE, combined with georeferenced occurrence records of mesophotic coral communities from autonomous underwater vehicle, remotely operated vehicle and SCUBA surveys. Model results are used to estimate the total amount of mesophotic coral reef habitat on the GBR.Results
Our models predict extensive but previously undocumented coral communities occurring both along the continental shelf-edge of the Great Barrier Reef and also on submerged reefs inside the lagoon. Habitat suitability for phototrophs is highest on submerged reefs along the outer-shelf and the deeper flanks of emergent reefs inside the GBR lagoon, while suitability for heterotrophs is highest in the deep waters along the shelf-edge. Models using only geophysical variables consistently outperformed models incorporating environmental data for both phototrophs and heterotrophs.Main Conclusion
Extensive submerged coral reef communities that are currently undocumented are likely to occur throughout the Great Barrier Reef. High-quality bathymetry data can be used to identify these reefs, which may play an important role in resilience of the GBR ecosystem to climate change. 相似文献43.
44.
Multiple-solvent crystal structure determination (MSCS) allows the position and orientation of bound solvent fragments to be identified by determining the structure of protein crystals soaked in organic solvents. We have extended this technique by the determination of high-resolution crystal structures of thermolysin (TLN), generated from crystals soaked in 2% to 100% isopropanol. The procedure causes only minor changes to the conformation of the protein, and an increasing number of isopropanol interaction sites could be identified as the solvent concentration is increased. Isopropanol occupies all four of the main subsites in the active site, although this was only observed at very high concentrations of isopropanol for three of the four subsites. Analysis of the isopropanol positions shows little correlation with interaction energy computed using a molecular mechanics force field, but the experimentally determined positions of isopropanol are consistent with the structures of known protein-ligand complexes of TLN. 相似文献
45.
46.
D. S. P. Patterson J. T. Done J. A. Foulkes D. Swfasey 《Journal of neurochemistry》1976,26(3):481-485
Abstract— In piglets affected with congenital tremor type AII the CNS was not morphologically underdeveloped; spinal cord weight, total DNA content and fat-free dry matter differed little from control values. However the total lipid extractable from affected spinal cords was only about 63% of values established for normal newborn piglets. In particular, the cerebroside content (a myelin-specific lipid) was reduced to about 30% of the 'normal' value. This was parallelled by the results of an in vitro assay of cerebroside synthesis from [3 H]galactose which indicated a metabolic impairment. The altered fatty acid profile of isolatcd cerebrosides further suggested a derangement of fatty acid synthesis. Unlike the spinal cords of normal newborn piglets, tissues from affected piglets contained significant amounts of cholesterol esters carrying the characteristic fatty acids associated with demyelination. This implied that the reduced quantities of possibly abnormal myelin were unstable. Abnormal swollen oligodendrocytes were commonly present in the spinal cords of affected piglets and this was consistcnt with the observed impairment of myelin formation. 相似文献
47.
ML Quick S Mukherjee CN Rudick JD Done AJ Schaeffer P Thumbikat 《American journal of physiology. Regulatory, integrative and comparative physiology》2012,303(6):R580-R589
Experimental autoimmune prostatitis (EAP) is a murine model of chronic prostatitis/chronic pelvic pain syndrome (CPPS) in men, a syndrome characterized by chronic pelvic pain. We have demonstrated that chemokine ligands CCL2 and CCL3 are biomarkers that correlate with pelvic pain symptoms. We postulated that CCL2 and CCL3 play a functional role in CPPS and therefore examined their expression in EAP. Upon examination of the prostate 5 days after induction of EAP, CCL2 mRNA was elevated 2- to 3-fold, CCL8 by 15-fold, CCL12 by 12- to 13-fold, and CXCL9 by 2- to 4-fold compared with control mice. At 10 days the major chemokines were CXCL13 and CXCL2; at 20 days CCL2 (1- to 2-fold), CCL3 (2- to 3-fold) and CCL11 (2- to 3-fold); and at 30 days, CCL12 (20- to 35-fold) and smaller increases in CCL2, CCL3, and XCL1. Chemokine elevations were accompanied by increases in mast cells and B cells at 5 days, monocytes and neutrophils at day 10, CD4+ T cells at day 20, and CD4+ and CD8+ T cells at day 30. Anti-CCL2 and anti-CCL3 neutralizing antibodies administered at EAP onset attenuated pelvic pain development, but only anti-CCL2 antibodies were effective therapeutically. CCL2- and its cognate receptor CCR2-deficient mice were completely protected from development of pain symptoms but assumed susceptibility after reconstitution with wild-type bone marrow. CCL3-deficient mice showed resistance to the maintenance of pelvic pain while CCR5-deficient mice did not show any lessening of pelvic pain severity. These results suggest that the CCL2-CCR2 axis and CCL3 are important mediators of chronic pelvic pain in EAP. 相似文献
48.
Jäger HC McKinley TJ Wood JL Pearce GP Williamson S Strugnell B Done S Habernoll H Palzer A Tucker AW 《PloS one》2012,7(2):e29655
A case-control investigation was undertaken to determine management and health related factors associated with pleurisy in slaughter pigs in England and Wales. METHODS: The British Pig Executive Pig Health Scheme database of abattoir pathology was used to identify 121 case (>10% prevalence of pleurisy on 3 or more assessment dates in the preceding 24 months) and 121 control units (≤5% prevalence of pleurisy on 3 or more assessment dates in the preceding 24 months). Farm data were collected by postal questionnaire. Data from respondents (70 cases and 51 controls) were analysed using simple logistic regression models with Bonferroni corrections. Limited multivariate analyses were also performed to check the robustness of the overall conclusions. RESULTS AND CONCLUSIONS: Management factors associated with increased odds of pleurisy included no all-in all-out pig flow (OR 9.3, 95% confidence interval [CI]: 3.3-29), rearing of pigs with an age difference of >1 month in the same airspace (OR 6.5 [2.8-17]) and repeated mixing (OR 2.2 [1.4-3.8]) or moving (OR 2.2 [1.5-3.4]) of pigs during the rearing phase. Those associated with decreased odds of pleurisy included filling wean-to-finish or grower-to-finish systems with piglets from ≤3 sources (OR 0.18 [0.07-0.41]) compared to farrow-to-finish systems, cleaning and disinfecting of grower (ORs 0.28 [0.13-0.61] and 0.29 [0.13-0.61]) and finisher (ORs 0.24 [0.11-0.51] and 0.2 [0.09-0.44]) accommodation between groups, and extended down time of grower and finisher accommodation (OR 0.84 [0.75-0.93] and 0.86 [0.77-0.94] respectively for each additional day of downtime). This study demonstrated the value of national-level abattoir pathology data collection systems for case control analyses and generated guidance for on-farm interventions to help reduce the prevalence of pleurisy in slaughter pigs. 相似文献
49.
Thérèse M. F. Tuohy Michelle W. Done Michelle S. Lewandowski Patricia M. Shires Devki S. Saraiya Sherry C. Huang Deborah W. Neklason Randall W. Burt 《Human genetics》2010,127(3):359-369
Familial adenomatous polyposis [FAP (OMIM 175100)] is an autosomal dominant colorectal cancer predisposition syndrome characterized
by hundreds to thousands of colonic polyps and, if untreated by a combination of screening and/or surgical intervention, a
~99% lifetime risk of colorectal cancer. A subset of FAP patients develop an attenuated form of the condition characterized
by lower numbers of colonic polyps (highly variable, but generally less than 100) and a lower lifetime risk of colorectal
cancer, on the order of 70%. We report the diagnosis of three attenuated FAP families due to a 1.4-kb deletion within intron
14 of APC, originally reported clinically as a variant of unknown significance (VUS). Sequence analysis suggests that this arose through
an Alu-mediated recombination event with a locus on chromosome 6q22.1. This mutation is inherited by family members who presented
with an attenuated FAP phenotype, with variable age of onset and severity. Sequence analysis of mRNA revealed an increase
in the level of aberrant splicing of exon 14, resulting in the generation of an exon 13–exon 15 splice-form that is predicted
to lead to a frameshift and protein truncation at codon 673. The relatively mild phenotypic presentation and the intra-familial
variation are consistent with the leaky nature of exon 14 splicing in normal APC. The inferred founder of these three families may account for as yet undetected affected branches of this kindred. This and
similar types of intronic mutations may account for a significant proportion of FAP cases where APC clinical analysis fails because of the current limitations of testing options. 相似文献
50.
The yield of F1 wheat hybrids is often limited by reduced male fertility. Improvement depends upon selecting male and female parents capable of allowing good fertility ‘restoration’ in the F1 hybrids. Assessment of restoring potential in growth rooms was difficult because fertility was much lower than in field grown plants. In the field, two experiments showed differences between parent lines but also that the fertilities of the F1 hybrids were site-specific, and that this factor might be considered during further selection. Variation between reciprocal crosses, possibly due to cytoplasmic differences, rendered a proposed test for the early assessment of fertility restoration capacity amongst potential male-sterile lines to be of doubtful value with present stocks. 相似文献