Phylogenetic patterns of diversification in a clade of Neotropical frogs (Anura: Aromobatidae: Mannophryne)

We used partial sequences of mitochondrial 16S and cytochrome oxidase I genes to perform a phylogenetic study of collared frogs (Anura: Aromobatidae: Mannophryne ), a genus endemic to Venezuela and the islands of Trinidad and Tobago. We analysed 1.2 kb from 13 of the 15 described species of Mannophryne . Maximum parsimony, maximum likelihood and Bayesian analyses support the monophyly of Mannophryne . Mannophryne consists of three deeply differentiated clades that split from each other in a relatively short period of time. The diversification of Mannophryne occurred well before the glacial-interglacial periods of the Quaternary. Our data support the taxonomic validity of M. olmonae , a species endemic to Tobago Island. Mannophryne olmonae is more closely related to the continental species Mannophryne riveroi than to the Trinidad island endemic Mannophryne trinitatis . As in most tropical clades of frogs, molecular evidence indicates that species richness in Mannophryne is largely underestimated and, consequently, current priorities for conservation are inadequate.  © 2009 The Linnean Society of London, Biological Journal of the Linnean Society , 2009, 97 , 185–199.     

A morphometric analysis of Daniellia (Fabaceae – Caesalpinioideae)

A multivariate morphometric study of Daniellia, an endemic genus of tropical and subtropical Africa, indicates that nine species may be recognized: D. alsteeniana, D. klainei, D. oblonga, D. ogea, D. oliveri, D. pilosa, D. pynaertii, D. soyauxii and D. thurifera. In our study we found that some characters, not previously studied in detail, were significant in species delimitation: petiole indumentum, petiole width, number and position of glands on the lower surface of the leaflets and presence or absence of glands at the insertion of each pair of leaflets. The rare and scattered material of D. pilosa and D. soyauxii made their classification uncertain, although some qualitative characters support their differentiation. © 2009 The Linnean Society of London, Botanical Journal of the Linnean Society, 2009, 159 , 268–279.     

Do synovial biopsies help to support evidence for involvement of innate immunity in the immunopathology of Beh?et's disease?

Behçet's disease is a complex vasculitis of unknown etiology. Abundant neutrophils suggest the involvement of innate immunity. Cytokines are skewed to the T-helper-1 pattern. Few sterile organs are easily accessible for analysis in Behçet's disease. Cañete and coworkers identify inflamed joints as a feasible model and suggest the involvement of innate immunity in Behçet's disease.     

Detection of the Bcl I polymorphism of the glucocorticoid receptor gene by single-tube allele-specific polymerase chain reaction

The Bcl I polymorphism of the glucocorticoid receptor gene, recently identified as an intronic C to G change 646 nucleotides downstream of exon 2, has been associated with increased sensitivity to glucocorticoids and its potential relevance in metabolic disturbances and in various disorders has been extensively investigated. In the present study, we designed a single-tube allele-specific polymerase chain reaction for genotyping this polymorphism in peripheral blood DNA samples. When the Bcl I polymorphism was detected with this novel method in a cohort of 247 healthy subjects, the observed genotype distribution matched the Hardy–Weinberg equilibrium (100 subjects homozygous for the wild-type, 124 heterozygous and 23 homozygous for the mutant allele). In 50 randomly selected subjects the Bcl I polymorphism was also determined using a traditional restriction fragment length polymorphism technique and DNA sequencing, and the results showed 100% coincidence with those obtained by our novel method. The method proved to be more rapid and less labour-intensive compared to currently used techniques, and it avoided the use of extensive instrumentals. We assume that this novel method may have a broad utility in clinical and molecular epidemiological studies aimed to elucidate the impact of the Bcl I polymorphism of the glucocorticoid receptor gene either on metabolic disturbances, or various disorders, including cancer treatment and hormone substitution therapies.     

The anxiety-like phenotype of 5-HT receptor null mice is associated with genetic background-specific perturbations in the prefrontal cortex GABA-glutamate system

A deficit in the serotonin 5-HT(1A) receptor has been found in panic and post-traumatic stress disorders, and genetic inactivation of the receptor results in an anxiety-like phenotype in mice on both the C57Bl6 and Swiss-Webster genetic backgrounds. Anxiety is associated with increased neuronal activity in the prefrontal cortex and here we describe changes in glutamate and GABA uptake of C57Bl6 receptor null mice. Although these alterations were not present in Swiss-Webster null mice, we have previously reported reductions in GABA(A) receptor expression in these but not in C57Bl6 null mice. This demonstrates that inactivation of the 5-HT(1A) receptor elicits different and genetic background-dependent perturbations in the prefrontal cortex GABA/glutamate system. These perturbations can result in a change in the balance between excitation and inhibition, and indeed both C57Bl6 and Swiss-Webster null mice show signs of increased neuronal excitability. Because neuronal activity in the prefrontal cortex controls the extent of response to anxiogenic stimuli, the genetic background-specific perturbations in glutamate and GABA neurotransmission in C57Bl6 and Swiss-Webster 5-HT(1A) receptor null mice may contribute to their shared anxiety phenotype. Our study shows that multiple strains of genetically altered mice could help us to understand the common and individual features of anxiety.     

Checklist of the Caesalpinioideae (Leguminosae) of Equatorial Guinea (Annobón, Bioko and Río Muni)

This study provides a checklist of the Caesalpinioideae (Leguminosae) present in Equatorial Guinea, comprising 52 genera and 124 taxa. Seven species are known from Annobón, 33 from Bioko and 109 from Río Muni. The best represented genus is Senna with eight species. In addition, bibliographic references for Caesalpinioideae (Leguminosae) from Equatorial Guinea have been gathered and checked. Fourteen species are included based on literature records, because their distribution ranges suggest they may occur in Equatorial Guinea, 11 introduced species could be naturalized, and 45 taxa are recorded for the first time from the country. This represents an increase of over 35% in the floristic knowledge of Caesalpinioideae from Equatorial Guinea. A statistical summary is presented at the end of the checklist.  © 2006 The Linnean Society of London, Botanical Journal of the Linnean Society , 2006, 151 , 541–562.     

Cardiac and skeletal muscle defects in a mouse model of human Barth syndrome

Barth syndrome is an X-linked genetic disorder caused by mutations in the tafazzin (taz) gene and characterized by dilated cardiomyopathy, exercise intolerance, chronic fatigue, delayed growth, and neutropenia. Tafazzin is a mitochondrial transacylase required for cardiolipin remodeling. Although tafazzin function has been studied in non-mammalian model organisms, mammalian genetic loss of function approaches have not been used. We examined the consequences of tafazzin knockdown on sarcomeric mitochondria and cardiac function in mice. Tafazzin knockdown resulted in a dramatic decrease of tetralinoleoyl cardiolipin in cardiac and skeletal muscles and accumulation of monolysocardiolipins and cardiolipin molecular species with aberrant acyl groups. Electron microscopy revealed pathological changes in mitochondria, myofibrils, and mitochondrion-associated membranes in skeletal and cardiac muscles. Echocardiography and magnetic resonance imaging revealed severe cardiac abnormalities, including left ventricular dilation, left ventricular mass reduction, and depression of fractional shortening and ejection fraction in tafazzin-deficient mice. Tafazzin knockdown mice provide the first mammalian model system for Barth syndrome in which the pathophysiological relationships between altered content of mitochondrial phospholipids, ultrastructural abnormalities, myocardial and mitochondrial dysfunction, and clinical outcome can be completely investigated.