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1.
Jeff A Johnson Heather RL Lerner Pamela C Rasmussen David P Mindell 《BMC evolutionary biology》2006,6(1):65-12
Background
Populations of the Oriental White-backed Vulture (Gyps bengalensis) have declined by over 95% within the past decade. This decline is largely due to incidental consumption of the non-steroidal anti-inflammatory veterinary pharmaceutical diclofenac, commonly used to treat domestic livestock. The conservation status of other Gyps vultures in southern Asia is also of immediate concern, given the lack of knowledge regarding status of their populations and the continuing existence of taxonomic uncertainties. In this study, we assess phylogenetic relationships for all recognized species and the majority of subspecies within the genus Gyps. The continuing veterinary use of diclofenac is an unknown but potential risk to related species with similar feeding habits to Gyps bengalensis. Therefore, an accurate assessment of the phylogenetic relationships among Gyps vultures should aid in their conservation by clarifying taxonomic uncertainties, and enabling inference of their respective relatedness to susceptible G. bengalensis. 相似文献2.
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4.
alpha 1-Proteinase inhibitor (alpha 1-PI), a member of the serine
proteinase inhibitor superfamily, has a primary role in controlling
neutrophil elastase activity within the mammalian circulation. Several
studies have indicated that the reactive center region of alpha 1-PI, the
amino acid sequence of which is critical to recognition of and binding to
target proteinases, is highly divergent within and among species. This
appears to be a consequence of accelerated rates of evolution that may have
been driven by positive Darwinian selection. In order to examine this and
other features of alpha 1-PI evolution in more detail, we have isolated and
sequenced cDNAs representing alpha 1- PI mRNAs of the mouse species Mus
saxicola and Mus minutoides and have compared these with a number of other
mammalian alpha 1-PI mRNAs. Relative to other mammalian mRNAs, the extent
of nonsynonymous substitution is generally high throughout the alpha 1-PI
mRNA molecule, indicating greater overall rates of amino acid substitution.
Within and among mouse species, the 5'-half of the mRNA, but not the
3'-half, has been homogenized by concerted evolution. Finally, the reactive
center is under diversifying or positive Darwinian selection in murid
rodents (rats, mice) and guinea pigs yet is under purifying selection in
primates and artiodactyls. The significance of these findings to alpha 1-PI
function and the possible selective forces driving evolution of serpins in
general are discussed.
相似文献
5.
Mitochondrial DNA polymorphisms in subterranean mole-rats of the Spalax ehrenbergi superspecies in Israel, and its peripheral isolates 总被引:1,自引:0,他引:1
Nevo E; Honeycutt RL; Yonekawa H; Nelson K; Hanzawa N 《Molecular biology and evolution》1993,10(3):590-604
Patterns of mitochondrial DNA (mtDNA) variation were examined in 133
mole-rats constituting all four chromosomal species (2n = 52, 2n = 54, 2n =
58, and 2n = 60) of the Spalax ehrenbergi superspecies in Israel, as well
as the peripheral isolates of 2n = 60. In the main range of the complex, a
total of 28 mtDNA haplotypes were found in 64 mole-rats, with most
haplotypes being unique to either a single chromosomal species or
population. mtDNA divergence increased from low to high diploid number in a
north-to-south direction in Israel. Overall levels of mtDNA diversity were
unexpectedly the highest in the 2n = 60, the youngest species of the
complex. The mtDNA haplotypes can be separated into two major groups, 2n =
52-54 and 2n = 58-60, and a phylogenetic analysis for each group revealed
evidence of a few haplotypes not sorted by diploid number. The overall
patterns of mtDNA divergence seen within and among the four chromosomal
species are consistent with the parapatric mode of speciation as suggested
from previous studies of allozyme and DNA hybridization. In a separate data
set the patterns of mtDNA variation were examined across the main
geographic range and across peripheral semi-isolates and isolates of the 2n
= 60 chromosomal species. Fifteen haplotypes were found in 69 mole-rats.
High levels of mtDNA diversity characterized the main range, semi-isolated,
and even some desert isolated populations. The peripheral isolates contain
much mtDNA diversity, including novel haplotypes.
相似文献
6.
7.
Kaustuv Basu Nancy Maurya Jasbir Kaur Rohit Saxena Viney Gupta Ramanjit Sihota Ilora Ghosh 《Cell biology international》2019,43(7):820-834
The pathological mechanism underlying glaucoma has always been a complex aspect of this permanently blinding disease but proteomic studies have been helpful in elucidating it to a great extent in several studies. This study was designed to evaluate the expression and to get an idea about the function of two novel markers (ligatin and fibulin‐7) identified in human aqueous humor (hAH) in relation to glaucomatous progression. A significant increase in the protein content of glaucomatous hAH compared to that of non‐glaucomatous controls (NG‐Ctrls) was observed. Ligatin, fibulin‐7, and its proteolysis were revealed in hAH of primary open angle glaucoma (POAG), primary angle closure glaucoma (PACG) and NG‐Ctrls. Quantification confirmed no significant difference in expression of ligatin, whereas fibulin‐7 was significantly (P < 0.05) low in hAH of PACG in comparison to NG‐Ctrls and POAG. Importantly the immunohistochemical assay for both indicated their possible involvement in the maintenance of the appropriate structure of TM in vivo. Since oxidative stress is a major contributor to glaucomatous pathogenesis, in vitro analysis of nuclear and cytoplasmic fractions indicated intracellular changes in localization and expression of ligatin upon oxidative insult of human trabecular meshwork (TM) cells. While no such changes were found for fibulin‐7 expression. This was also corroborated with the immunocytochemical assay. Though a study with a small sample size, this is the first report which confirms the presence of ligatin and fibulin‐7 in hAH, quantified their differential expression, and indicated the possibility of their involvement in the maintenance of the TM structure. 相似文献
8.
Margaret Campbell Naomi van der Linden Karen Gardner Helen Dickinson Jason Agostino Michelle Dowden Irene OMeara Meg Scolyer Hannah Woerle Rosalie Viney Kees van Gool 《PLoS neglected tropical diseases》2022,16(3)
BackgroundCrusted scabies is a debilitating dermatological condition. Although still relatively rare in the urban areas of Australia, rates of crusted scabies in remote Aboriginal communities in the Northern Territory (NT) are reported to be among the highest in the world.ObjectiveTo estimate the health system costs associated with diagnosing, treating and managing crusted scabies.MethodsA disease pathway model was developed to identify the major phases of managing crusted scabies. In recognition of the higher resource use required to treat more severe cases, the pathway differentiates between crusted scabies severity grades. The disease pathway model was populated with data from a clinical audit of 42 crusted scabies patients diagnosed in the Top-End of Australia’s Northern Territory between July 1, 2016 and May 1, 2018. These data were combined with standard Australian unit costs to calculate the expected costs per patient over a 12-month period, as well as the overall population cost for treating crusted scabies.FindingsThe expected health care cost per patient diagnosed with crusted scabies is $35,418 Australian dollars (AUD) (95% CI: $27,000 to $43,800), resulting in an overall cost of $1,558,392AUD (95% CI: $1,188,000 to $1,927,200) for managing all patients diagnosed in the Northern Territory in a given year (2018). By far, the biggest component of the health care costs falls on the hospital system.DiscussionThis is the first cost-of-illness analysis for treating crusted scabies. Such analysis will be of value to policy makers and researchers by informing future evaluations of crusted scabies prevention programs and resource allocation decisions. Further research is needed on the wider costs of crusted scabies including non-financial impacts such as the loss in quality of life as well as the burden of care and loss of well-being for patients, families and communities. 相似文献
9.
Burich A Hershberg R Waggie K Zeng W Brabb T Westrich G Viney JL Maggio-Price L 《American journal of physiology. Gastrointestinal and liver physiology》2001,281(3):G764-G778
Inflammatory bowel disease (IBD) is thought to result from a dysregulated mucosal immune response to luminal microbial antigens, with T lymphocytes mediating the colonic pathology. Infection with Helicobacter spp has been reported to cause IBD in immunodeficient mice, some of which lack T lymphocytes. To further understand the role of T cells and microbial antigens in triggering IBD, we infected interleukin (IL)-10(-/-), recombinase-activating gene (Rag)1(-/-), T-cell receptor (TCR)-alpha(-/-), TCR-beta(-/-), and wild-type mice with Helicobacter hepaticus or Helicobacter bilis and compared the histopathological IBD phenotype. IL-10(-/-) mice developed severe diffuse IBD with either H. bilis or H. hepaticus, whereas Rag1(-/-), TCR-alpha(-/-), TCR-beta(-/-), and wild-type mice showed different susceptibilities to Helicobacter spp infection. Proinflammatory cytokine mRNA expression was increased in the colons of Helicobacter-infected IL-10(-/-) and TCR-alpha(-/-) mice with IBD. These results confirm and extend the role of Helicobacter as a useful tool for investigating microbial-induced IBD and show the importance, but not strict dependence, of T cells in the development of bacterial-induced IBD. 相似文献
10.
Phylogenetic utility of the nuclear gene arginine decarboxylase: an example from Brassicaceae 总被引:10,自引:2,他引:8
Arginine decarboxylase (ADC) is an important enzyme in the production of
putrescine and polyamines in plants. It is encoded by a single or low-copy
nuclear gene that lacks introns in sequences studied to date. The rate of
Adc amino acid sequence evolution is similar to that of ndhF for the
angiosperm family studied. Highly conserved regions provide several target
sites for PCR priming and sequencing and aid in nucleotide and amino acid
sequence alignment across a range of taxonomic levels, while a variable
region provides an increased number of potentially informative characters
relative to ndhF for the taxa surveyed. The utility of the Adc gene in
plant molecular systematic studies is demonstrated by analysis of its
partial nucleotide sequences obtained from 13 representatives of
Brassicaceae and 3 outgroup taxa, 2 from the mustard oil clade (order
Capparales) and 1 from the related order Malvales. Two copies of the Adc
gene, Adc1 and Adc2, are found in all members of the Brassicaceae studied
to data except the basal genus Aethionema. The resulting Adc gene tree
provides robust phylogenetic data regarding relationships within the
complex mustard family, as well as independent support for proposed tribal
realignments based on other molecular data sets such as those from
chloroplast DNA.
相似文献