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81.
Matthew N Ward Allison M Churcher Kevin J Dick Chris RJ Laver Greg L Owens Megan D Polack Pam R Ward Felix Breden John S Taylor 《BMC evolutionary biology》2008,8(1):210
Background
Comparisons of functionally important changes at the molecular level in model systems have identified key adaptations driving isolation and speciation. In cichlids, for example, long wavelength-sensitive (LWS) opsins appear to play a role in mate choice and male color variation within and among species. To test the hypothesis that the evolution of elaborate coloration in male guppies (Poecilia reticulata) is also associated with opsin gene diversity, we sequenced long wavelength-sensitive (LWS) opsin genes in six species of the family Poeciliidae. 相似文献82.
C. Teunissen N. Clappers R. J. Hassink J. F. van der Heijden F. H. Wittkampf P. Loh 《Netherlands heart journal》2017,25(10):559-566
Background
Over the past decade, radiofrequency catheter ablation (RFCA) of atrial fibrillation (AF) has evolved into a frequently performed procedure. The aim of this study was to monitor changes in patient characteristics, procedural characteristics, outcomes and complications over the past 10 years.Methods
All consecutive patients who underwent primary RFCA treatment of AF in the University Medical Center Utrecht from 2005–2015 were included. In all patients, the primary ablation strategy was pulmonary vein (PV) antrum isolation without additional substrate modification. Baseline patient and procedure characteristics, and 1?year follow-up data of 975 patients were prospectively collected.Results
In 2005, 73.4% of patients suffered from paroxysmal AF, which decreased to 45.3% in 2014. Mean age increased from 54 ± 9 to 61 ± 10 years and CHA2DS2-VASc score ≥2 from 18 to 40.6%. History of AF decreased significantly from 7 to 4 years. Mean procedure duration was 237 ± 53?min in 2005 and 163 ± 41?min in 2014. Fluoroscopy time significantly decreased from 41 ± 17 to 19 ± 8?min and total radiation exposure from 465 (263–687) to 210 (118–376) mGy. One-year success remained similar (2005: 55.6%, 2014: 54.8%), as did the amount of PV reconnection observed during redo procedures. Due to a marked reduction in vascular complications and moderate PV stenosis, the total complication rate decreased significantly.Conclusion
Over the past decade, AF ablation has increasingly been performed in older patients with persistent AF and more comorbidity. Moreover, it has been performed earlier after AF diagnosis. Although several performance parameters, such as procedure duration and complication rate, improved, 1?year single procedure success remained unchanged.83.
High frequency hearing loss correlated with mutations in the GJB2 gene 总被引:18,自引:0,他引:18
Wilcox SA Saunders K Osborn AH Arnold A Wunderlich J Kelly T Collins V Wilcox LJ McKinlay Gardner RJ Kamarinos M Cone-Wesson B Williamson R Dahl HH 《Human genetics》2000,106(4):399-405
Genetic hearing impairment affects approximately 1/2000 live births. Mutations in one gene, GJB2, coding for connexin 26 cause 10%-20% of all genetic sensorineural hearing loss. Mutation analysis in the GJB2 gene and audiology were performed on 106 families presenting with at least one child with congenital hearing loss. The families were recruited from a hospital-based multidisciplinary clinic, which functions to investigate the aetiology of sensorineural hearing loss in children and which serves an ethnically diverse population. In 74 families (80 children), the aetiology was consistent with non-syndromic recessive hearing loss. Six different connexin 26 mutations, including one novel mutation, were identified. We show that GJB2 mutations cause a range of phenotypes from mild to profound hearing impairment and that loss of hearing in the high frequency range (4000-8000 Hz) is a characteristic feature in children with molecularly diagnosed connexin 26 hearing impairment. We also demonstrate that this type of audiology and high frequency hearing loss is found in a similar-sized group of deaf children in whom a mutation could only be found in one of the connexin 26 alleles, suggesting connexin 26 involvement in the aetiology of hearing loss in these cases. In our study of the M34T mutation, only compound heterozygotes exhibited hearing loss, suggesting autosomal recessive inheritance. 相似文献
84.
85.
Molecular phylogenetics of Stenodermatini bat genera: congruence of data from nuclear and mitochondrial DNA 总被引:2,自引:1,他引:1
Van den Bussche RA; Baker RJ; Wichman HA; Hamilton MJ 《Molecular biology and evolution》1993,10(5):944-959
Within the tribe Stenodermatini the systematics of the complex of species
allied with the genus Artibeus has generated several alternative
phylogenetic hypotheses. The most recent treatment recognized four genera
(Artibeus, Dermanura, Enchisthenes, and Koopmania) and suggested that the
most recent common ancestor of these four genera would include the common
ancestor of all other currently recognized Stenodermatini genera except
Sturnira. To test this hypothesis, we examined an EcoRI-defined nuclear
satellite DNA repeat and 402 bp of DNA sequence variation from the
mitochondrial cytochrome b gene. Phylogenetic conclusions based on Southern
blot analyses, in situ hybridization, and mitochondrial DNA sequence data
indicate that Enchisthenes is not closely related to Dermanura, Artibeus,
or Koopmania and that Dermanura, Artibeus, and Koopmania shared a common
ancestor after diverging from the remainder of the Stenodermatini. If our
conclusions are correct, then justification for recognizing Dermanura and
Koopmania as generically distinct from Artibeus must be based on the
magnitude of difference that distinguishes each rather than on the
conclusion that to place them as congeneric with Artibeus creates a
paraphyletic taxon.
相似文献
86.
87.
88.
Immunological similarities between specific chloroplast ribosomal proteins from Chlamydomonas reinhardtii and ribosomal proteins from Escherichia coli 总被引:11,自引:0,他引:11
Polyclonal antibodies were elicited against seven of the 33 different
proteins of the large subunit of the chloroplast ribosome from
Chlamydomonas reinhardtii. Three of these proteins are synthesized in the
chloroplast and four are made in the cytoplasm and imported. In western
blots, six of the seven antisera are monospecific for their respective
large subunit ribosomal proteins, and none of these antisera cross-reacted
with any chloroplast small subunit proteins from C. reinhardtii. Antisera
to the three chloroplast-synthesized ribosomal proteins cross-reacted with
specific Escherichia coli large subunit proteins of comparable charge and
molecular weight. Only one of the four antisera to the chloroplast
ribosomal proteins synthesized in the cytoplasm cross-reacted with an E.
coli large subunit protein. None of the antisera cross-reacted with any E.
coli small subunit proteins. On the assumption of a procaryotic,
endosymbiotic origin for the chloroplast, those chloroplast ribosomal
proteins still synthesized within the organelle appear to have retained
more antigenic sites in common with E. coli ribosomal proteins than have
those which are now the products of cytoplasmic protein synthesis. Antisera
to this cytoplasmically synthesized group of chloroplast ribosomal proteins
did not recognize any antigenic sites among C. reinhardtii cytoplasmic
ribosomal proteins, suggesting that the genes for the cytoplasmically
synthesized chloroplast ribosomal proteins either are not derived from the
cytoplasmic ribosomal protein genes or have evolved to a point where no
antigenic similarities remain.
相似文献
89.
Background
Four hypervariable minisatellite loci were scored on a panel of 116 individuals of various geographical origins representing a large part of the diversity present in house mouse subspecies. Internal structures of alleles were determined by minisatellite variant repeat mapping PCR to produce maps of intermingled patterns of variant repeats along the repeat array. To reconstruct the genealogy of these arrays of variable length, the specifically designed software MS_Align was used to estimate molecular divergences, graphically represented as neighbor-joining trees. 相似文献90.