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Norma J. Sharratt Mike D. Picker Michael J. Samways 《Biodiversity and Conservation》2000,9(1):107-143
The temperate sandstone caves of the Cape Peninsula, South Africa, support 85 cavernicolous invertebrate species across six phyla. Six of these, including two blind and depigmented species of insects (Dermaptera) and spiders (Araneae: Hahniidae) were previously unknown. Twenty-one species are endemic to the Peninsula. Thirteen of these are presumed troglobitic Gondwanan relicts, including highly specialized, phylogenetically unique, rare species with restricted distributions and specialized habitat requirements. According to the criteria listed in the IUCN Red List Categories (1994), the onychophoran Peripatopsis alba and crustacean Spelaeogriphus lepidops should be considered Critically Endangered, their extents of occurrence being less than 100km2. Furthermore, Data Deficient species, such as the freshwater shrimps Protojanira leleupi and Paramelita barnardi, the spider Hahnia sp.nov., the earwig Dermaptera sp.nov. and the centipede Cryptops stupendus, are likely to be additional Critically Endangered species on account of their exceptional rarity or restricted distributions. The remaining endemic cavernicoles are considered Endangered on account of their limited distributions (extent of occurrence <5000km2). Therefore, conservation considerations are clearly an urgent priority and appropriate recommendations are provided. Management-orientated research, long-term population monitoring and the conservation of pseudokarst areas, are urgent requirements for the conservation of these rare and threatened evolutionary relicts in their isolated island-like habitats. 相似文献
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Background
Elucidation of the communal behavior of microbes in mixed species biofilms may have a major impact on understanding infectious diseases and for the therapeutics. Although, the structure and the properties of monospecies biofilms and their role in disease have been extensively studied during the last decade, the interactions within mixed biofilms consisting of bacteria and fungi such as Candida spp. have not been illustrated in depth. Hence, the aim of this study was to evaluate the interspecies interactions of Pseudomonas aeruginosa and six different species of Candida comprising C. albicans, C. glabrata, C. krusei, C. tropicalis, C. parapsilosis, and C. dubliniensis in dual species biofilm development. 相似文献15.
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JG Hansen W Gao J Dupuis GT O’Connor W Tang M Kowgier A Sood SA Gharib LJ Palmer M Fornage SR Heckbert BM Psaty SL Booth SUNLIGHT Consortium Patricia A Cassano 《Respiratory research》2015,16(1)
Background
Vitamin D is associated with lung function in cross-sectional studies, and vitamin D inadequacy is hypothesized to play a role in the pathogenesis of chronic obstructive pulmonary disease. Further data are needed to clarify the relation between vitamin D status, genetic variation in vitamin D metabolic genes, and cross-sectional and longitudinal changes in lung function in healthy adults.Methods
We estimated the association between serum 25-hydroxyvitamin D [25(OH)D] and cross-sectional forced expiratory volume in the first second (FEV1) in Framingham Heart Study (FHS) Offspring and Third Generation participants and the association between serum 25(OH)D and longitudinal change in FEV1 in Third Generation participants using linear mixed-effects models. Using a gene-based approach, we investigated the association between 241 SNPs in 6 select vitamin D metabolic genes in relation to longitudinal change in FEV1 in Offspring participants and pursued replication of these findings in a meta-analyzed set of 4 independent cohorts.Results
We found a positive cross-sectional association between 25(OH)D and FEV1 in FHS Offspring and Third Generation participants (P = 0.004). There was little or no association between 25(OH)D and longitudinal change in FEV1 in Third Generation participants (P = 0.97). In Offspring participants, the CYP2R1 gene, hypothesized to influence usual serum 25(OH)D status, was associated with longitudinal change in FEV1 (gene-based P < 0.05). The most significantly associated SNP from CYP2R1 had a consistent direction of association with FEV1 in the meta-analyzed set of replication cohorts, but the association did not reach statistical significance thresholds (P = 0.09).Conclusions
Serum 25(OH)D status was associated with cross-sectional FEV1, but not longitudinal change in FEV1. The inconsistent associations may be driven by differences in the groups studied. CYP2R1 demonstrated a gene-based association with longitudinal change in FEV1 and is a promising candidate gene for further studies.Electronic supplementary material
The online version of this article (doi:10.1186/s12931-015-0238-y) contains supplementary material, which is available to authorized users. 相似文献18.
Monika J. B. Eberhard Mike D. Picker Klaus-Dieter Klass 《Organisms Diversity & Evolution》2011,11(1):43-59
We describe a new genus of Mantophasmatodea, Viridiphasma gen. n. (Austrophasmatidae), represented by one new species, V. clanwilliamense sp. n. The new species differs from previously described species in features of the male and female postabdomen including
the genitalia, in morphometrics and details of colouration. The new species occurs syntopically with another austrophasmatid,
Karoophasma biedouwense Klass et al., 2003; this is the first well-documented case of sympatry of two mantophasmatodean species. We therefore survey
the morphological differences between these two species, document the absence of any morphological evidence of hybridisation,
and also report on differences in life history. While a previous molecular phylogeny using COI and 16S genes ambiguously placed
V. clanwilliamense sp. n. near the base of Austrophasmatidae (but not as sister to all other Austrophasmatidae), morphological characters strongly
support V. clanwilliamense sp. n. to be the sister taxon of a clade comprising all remaining Austrophasmatidae. This phylogenetic placement challenges
the current hypothesis of a linear north-to-south diversification of Austrophasmatidae. 相似文献
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M.?Rützler LJ?ZwiebelEmail author 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》2005,191(9):777-790
Insects have an enormous impact on global public health as disease vectors and as agricultural enablers as well as pests and
olfaction is an important sensory input to their behavior. As such it is of great value to understand the interplay of the
molecular components of the olfactory system which, in addition to fostering a better understanding of insect neurobiology,
may ultimately aid in devising novel intervention strategies to reduce disease transmission or crop damage. Since the first
discovery of odorant receptors in vertebrates over a decade ago, much of our view on how the insect olfactory system might
work has been derived from observations made in vertebrates and other invertebrates, such as lobsters or nematodes. Together
with the advantages of a wide range of genetic tools, the identification of the first insect odorant receptors in Drosophila melanogaster in 1999 paved the way for rapid progress in unraveling the question of how olfactory signal transduction and processing occurs
in the fruitfly. This review intends to summarize much of this progress and to point out some areas where advances can be
expected in the near future. 相似文献
20.
This study presents the first physiological information for a member of the wingless Mantophasmatodea, or Heelwalkers. This species shows cyclic gas exchange with no evidence of a Flutter period (more typical of discontinuous gas exchange in insects) and no indication that the spiracles are fully occluded during quiescent metabolism. Standard metabolic rate at 20 degrees C was 21.32+/-2.73 microl CO(2)h(-1) (mean+/-S.E.), with a Q(10) (10-25 degrees C) of 1.7. Increases in V()CO(2) associated with variation in mass and with trial temperature were modulated by an increase in burst period volume and a decline in cycle frequency. Total water loss rate, determined by infrared gas analysis, was 0.876+/-0.08 mg H(2)Oh(-1) (range 0.602-1.577, n=11) whilst cuticular water loss rate, estimated by linear regression of total water loss rate and metabolic rate, was 0.618+/-0.09 mg H(2)Oh(-1) (range 0.341-1.363, n=11). Respiratory water loss rate was therefore no more than 29% of the total rate of water loss. Both total water loss rate and estimated cuticular water loss rate were significantly repeatable, with intraclass correlation coefficients of 0.745 and 0.553, respectively. 相似文献