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At least 613 records · Page 34Linked to original sources
PubMed2005

The evolution and function of adult attachment: a comparative and phylogenetic analysis.

Although the evolutionary functions of attachment in infant-caregiver relationships are undisputed, it is unclear what functions--if any--attachment serves in adult romantic relationships. The objective of this research was to examine the evolution and function of adult attachment (i.e., pair bonding) by applying comparative and phylogenetic methods to archival data collected on 2 diverse samples of mammalian species. The authors found that species exhibiting adult attachment were more likely than others to be characterized by paternal care, developmental immaturity or neoteny, small social groups, and small body sizes. The authors also used phylogenetic techniques to reconstruct the evolution of adult attachment and test alternative evolutionary models of the comparative correlates of pair bonding. Phylogenetic analyses suggested that the relationship between paternal care and adult attachment may be a functional one (i.e., due to convergent evolution) but that the relationship between neoteny and adult attachment may be due to homology (i.e., shared ancestry). Discussion focuses on the potential of comparative and phylogenetic methods for advancing the science of social and personality psychology.

Adult↗
PubMed2000

Zebrafish comparative genomics and the origins of vertebrate chromosomes.

To help understand mechanisms of vertebrate genome evolution, we have compared zebrafish and tetrapod gene maps. It has been suggested that translocations are fixed more frequently than inversions in mammals. Gene maps showed that blocks of conserved syntenies between zebrafish and humans were large, but gene orders were frequently inverted and transposed. This shows that intrachromosomal rearrangements have been fixed more frequently than translocations. Duplicated chromosome segments suggest that a genome duplication occurred in ray-fin phylogeny, and comparative studies suggest that this event happened deep in the ancestry of teleost fish. Consideration of duplicate chromosome segments shows that at least 20% of duplicated gene pairs may be retained from this event. Despite genome duplication, zebrafish and humans have about the same number of chromosomes, and zebrafish chromosomes are mosaically orthologous to several human chromosomes. Is this because of an excess of chromosome fissions in the human lineage or an excess of chromosome fusions in the zebrafish lineage? Comparative analysis suggests that an excess of chromosome fissions in the tetrapod lineage may account for chromosome numbers and provides histories for several human chromosomes.

Animals↗
PubMed2004

Karyotypic evolution of Apodemus (Muridae, Rodentia) inferred from comparative FISH analyses.

We conducted comparative FISH analyses to investigate the chromosomal rearrangements that have occurred during the evolution of the rodent genus Apodemus, which inhabits broadleaf forests in the temperate zone of the Palaearctic region. Chromosome-specific painting probes of the laboratory mouse were hybridized to chromosomes of seven Apodemus species, A. agrarius, A. argenteus, A. gurkha, A. peninsulae, A. semotus, A. speciosus and A. sylvaticus, and homologous chromosomal regions were determined in the species for the study of karyotypic evolution. Differences in the hybridization patterns were found in nine pairs of autosomes among the seven species. The chromosomal location of the 5S rRNA genes on the telomeric region of chromosome 20 was highly conserved in all the species. In contrast, there was much wider variation in the location of the 18S-28S rRNA genes, although they were predominantly located on chromosomes 7, 8 and 12. Phylogenetic relationships of the seven Apodemus species were inferred from the chromosome rearrangements and the chromosomal distribution patterns of the 18S-28S rRNA genes. The karyotypic relationships correlated well with the molecular phylogeny, and A. semotus had the most highly conserved karyotype among the seven species.

Animals↗
PubMedDate not supplied

[The late evolution of bronchial asthma appearing in children].

A retrospective study was performed in order to compare the clinical evolution of chronic bronchial asthma with onset in childhood with that of bronchial asthma registered at adult age. The group included 150 cases (87 females and 63 males) out of which 108 (72%) asthma with late onset and 42 (28%) asthma symptoms registered in childhood and adolescence. The symptoms were: allergic rhinitis and spastic tracheobronchitis in 18 (42.8%), dyspneic recurrent bronchitis in 16 (38%), nasal polyposis in 4 (9.5%) and atopic dermatitis in 4 (9.5%) cases. A possible allergic etiology was not taken into consideration in these cases. According to the data obtained, it results that the evolution and the prognosis of bronchial asthma are more severe in patients with its onset in childhood, where there were noted: more severe clinical forms of the disease, higher ventilation dysfunction, more numerous social (family) consequences of the disease, and a higher necessity of long term, systemic corticotherapy than in cases of bronchial asthma with late onset. The delay in the preventive treatment or an incorrect application of it in childhood will condition to a great extent the unfavourable evolution of the disease.

Adrenal Cortex Hormones↗
PubMed1998

Retrospective study on the evolution of visual acuity after external beam radiotherapy (20 Gy, 2 Gy fractions) for subfoveal choroidal neovascular membranes in ARMD.

This is a retrospective study of 104 patients with a total follow-up between 12 and 48 months (mean follow-up of 24 months), in which the effect of External Beam Radiotherapy with a total dose of 20 Gy (2 Gy fractions) on the visual acuity of eyes affected by subfoveal choroidal neovascularization is evaluated. The evolution of the visual acuity of the irradiated eyes is compared with the evolution of the visual acuity of their fellow eyes which were also affected by choroidal neovascularization but were not treated or treated by laser photocoagulation. This study suggests that the effect of radiotherapy, with a total dose of 20 Gy, on the visual acuity of eyes affected by subfoveal choroidal neovascularization, seems to be not better than the natural course of choroidal neovascularization or the evolution after laser therapy.

Adult↗
PubMed2001

[Acute cholangitis caused by choledocholithiasis: traditional surgery or endoscopic biliary drainage].

BACKGROUND: Endoscopic drainage of the biliary tree for acute cholangitis is a therapeutic modality with a lower mortality and complication rates. AIM: To compare endoscopic drainage with surgical treatment in the emergency management of acute cholangitis. PATIENTS AND METHODS: Between 1995 and 1998, sixty five patients with acute cholangitis were subjected to an endoscopic drainage of the biliary tree. In the same period, 40 patients were treated with traditional surgical procedures. The evolution of both groups of patients were compared. RESULTS: Sixty two patients (95.4%) subjected to endoscopic treatment had a satisfactory evolution, compared with 23 (58%) of those operated (p < 0.001). Five operated patients and no individual subjected to endoscopic drainage died (p < 0.01). Mean postoperative hospital stay of operated patients was 15.5 +/- 19.6 days compared to 5.8 +/- 4.2 days in those subjected to endoscopic drainage (p < 0.001). Definitive resolution of biliary obstruction was achieved in 83% of patients subjected to endoscopic drainage or traditional surgery. CONCLUSIONS: Endoscopic drainage has a lower rate of complications and mortality than traditional surgery, in the treatment of acute cholangitis.

Acute Disease↗
PubMed2005

Molecular cytogenetics and tandem repeat sequence evolution in the allopolyploid Nicotiana rustica compared with diploid progenitors N. paniculata and N. undulata.

Nicotiana rustica (2n = 4x = 48) is a natural allotetraploid composed of P and U genomes which are closely related to genomes of diploid species N. paniculata and N. undulata. Genomic in situ hybridization (GISH) also confirms that the diploid parents, or close relatives, are the ancestors of N. rustica. In order to study genetic interactions between ancestral genomes in the allotetraploid, we isolated three families of repetitive sequences, two from N. paniculata (NPAMBE and NPAMBO) and one from N. undulata (NUNSSP). Southern blot hybridization revealed that the sequences are digested with a range of restriction enzymes into regular ladder patterns indicating a tandem arrangement of high copy repeats possessing monomeric units of about 180 bp. The three-tandem sequences belong to a larger Nicotiana tandem repeat family called here the HRS-60 family. Members of this family are found in all Nicotiana species studied. Fluorescence in situ hybridization (FISH) analysis localized the satellite repeats to subtelomeric regions of most chromosomes of N. paniculata and N. undulata. The pattern of sequence distribution on the P- and U-genomes of N. rustica was similar to the putative parents N. paniculata and N. undulata respectively. However, NPAMBO repeats appear to be reduced and rearranged in N. rustica that may suggest evolution within the P genome. GISH and FISH with the tandem repeat probes failed to reveal intergenomic translocations as might be predicted from the nucleocytoplasmic interaction hypothesis.

Chromatin↗
PubMed2003

Testing the link between the latitudinal gradient in species richness and rates of molecular evolution.

Numerous hypotheses have been proposed to explain latitudinal gradients in species richness, but all are subject to ongoing debate. Here we examine Rohde's (1978, 1992) hypothesis, which proposes that climatic conditions at low latitudes lead to elevated rates of speciation. This hypothesis predicts that rates of molecular evolution should increase towards lower latitudes, but this prediction has never been tested. We discuss potential links between rates of molecular evolution and latitudinal diversity gradients, and present the first test of latitudinal variation in rates of molecular evolution. Using 45 phylogenetically independent, latitudinally separated pairs of bird species and higher taxa, we compare rates of evolution of two mitochondrial genes and DNA-DNA hybridization distances. We find no support for an effect of latitude on rate of molecular evolution. This result casts doubt on the generality of a key component of Rohde's hypothesis linking climate and speciation.

Animals↗
PubMed1987

[Horton's disease and rhizomelic pseudopolyarthritis. Developmental data apropos of 95 cases].

The many common factors linking rhizomelic pseudopolyarthritis and Horton's disease prompt to compare their respective evolutions and the long-term results of their treatments. The comparative study of 28 patients with temporal Horton's arteritis, proven histologically, and 28 rhizomelic pseudopolyarthritis without arteritis on biopsy, in a total population of 95 patients, confirms the similarity of their clinical and biological signs and show a closely related evolution in the three groups. The evolution leads to a cure approximately 16.4 +/- 14 months in 41 p. cent of the cases. 34 p. cent of the patients are at an advanced stage with a mean follow-up of 37 months and relapses during the weaning period were frequent. 25 p. cent of the patients died. Most deaths occur in the first month of the disease, and occur readily in patients who have received a short treatment with steroids discontinued because of a iatrogenic accident. Cerebral vascular accidents and coronary accidents, arterial hypertension and iatrogenic gastro-intestinal ulcerations are the most frequent complications.

Aged↗
PubMed2006

Genome architecture drives protein evolution in ciliates.

Studies of microbial eukaryotes have been pivotal in the discovery of biological phenomena, including RNA editing, self-splicing RNA, and telomere addition. Here we extend this list by demonstrating that genome architecture, namely the extensive processing of somatic (macronuclear) genomes in some ciliate lineages, is associated with elevated rates of protein evolution. Using newly developed likelihood-based procedures for studying molecular evolution, we investigate 6 genes to compare 1) ciliate protein evolution to that of 3 other clades of eukaryotes (plants, animals, and fungi) and 2) protein evolution in ciliates with extensively processed macronuclear genomes to that of other ciliate lineages. In 5 of the 6 genes, ciliates are estimated to have a higher ratio of nonsynonymous/synonymous substitution rates, consistent with an increase in the rate of protein diversification in ciliates relative to other eukaryotes. Even more striking, there is a significant effect of genome architecture within ciliates as the most divergent proteins are consistently found in those lineages with the most highly processed macronuclear genomes. We propose a model whereby genome architecture-specifically chromosomal processing, amitosis within macronuclei, and epigenetics-allows ciliates to explore protein space in a novel manner. Further, we predict that examination of diverse eukaryotes will reveal additional evidence of the impact of genome architecture on molecular evolution.

Animals↗
PubMed2001

Evolutionary genomics of pathogenic bacteria.

Complete genome sequences are now available for multiple strains of several bacterial pathogens and comparative analysis of these sequences is providing important insights into the evolution of bacterial virulence. Recently, DNA microarray analysis of many strains of several pathogenic species has contributed to our understanding of bacterial diversity, evolution and pathogenesis. Comparative genomics has shown that pathogens such as Escherichia coli, Helicobacter pylori and Staphylococcus aureus contain extensive variation in gene content whereas Mycobacterium tuberculosis nucleotide divergence is very limited. Overall, these approaches are proving to be a powerful means of exploring bacterial diversity, and are providing an important framework for the analysis of the evolution of pathogenesis and the development of novel antimicrobial agents.

Bacteria↗
PubMed1997

A mammalian homologue of the Drosophila retinal degeneration B gene: implications for the evolution of phototransduction mechanisms.

Comparative analysis of homologous genes in distantly related species provides important insights into the evolution of complex physiological processes. The Drosophila retinal degeneration B (rdgB) gene encodes a protein involved in phototransduction in the fly. We have isolated a human gene, DRES9, and its murine homologue (Dres9), which show a high degree of similarity to the Drosophila rdgB gene. RNA in situ hybridization studies performed on mouse-embryo tissue sections at various developmental stages revealed that Dres9 is expressed at very high levels in the neural retina and in the central nervous system (CNS), similar to its Drosophila counterpart. The high level of sequence conservation and similarities in the expression patterns of rdgB and DRES9 during development in Drosophila and mammals indicate that Dres9 is the orthologue of RdgB, and strongly suggest a possible functional conservation of these proteins during evolution. DRES9 encodes a phosphatidylinositol-transfer protein, suggesting that phosphatidylinositol may have a role as an intracellular messenger in vertebrate phototransduction. The identification of this gene and the study of its expression pattern in mammals will help shed new light on the evolution of vision mechanisms and suggest DRES9 as a candidate gene for human retinopathies.

Amino Acid Sequence↗
PubMed2003

Evolution of chromatin-remodeling complexes: comparative genomics reveals the ancient origin of "novel" compensasome genes.

Dosage compensation in Drosophila is mediated by a complex, called compensasome, composed of at least five proteins and two noncoding RNAs. Genes encoding compensasome proteins have been collectively named male-specific lethals or msls. Recent work showed that three of the Drosophila msls (msl-3, mof, and mle) have an ancient origin. In this study, I describe likely orthologues of the two remaining msls, msl-1 and msl-2, in several invertebrates and vertebrates. The MSL-2 protein is the only one found in Drosophila and vertebrate genomes that contains both a RING finger and a peculiar type of CXC domain, related to the one present in Enhancer of Zeste proteins. MSL-1 also contains two evolutionarily conserved domains: a leucine zipper and a second characteristic region, described here for the first time, which I have called the PEHE domain. These two domains are present in the likely orthologues of MSL-1 as well as in other genes in several invertebrate and vertebrate species. Although it cannot be excluded that the compensasome complex is a recent evolutionary novelty, these results shows that all msls are found in mammals, suggesting that protein complexes related to the compensasome may be present in mammalian species. Metazoans that lack several of the msls, such as Caenorhabditis elegans, cannot contain compensasomes. The evolutionary relationships of the compensasome and the NuA4 complex, another chromatin-remodeling complex that contains related subunits, are discussed.

Amino Acid Motifs↗