Description of five new species of the Madagascan flagship plant genus Ravenala (Strelitziaceae).

Madagascar's emblematic traveller's tree is a monospecific genus within Strelitziaceae, the family of the South African bird of paradise. Until now, this endemic genus consisted of a single species: Ravenala madagascariensis Sonn., which is grown everywhere in the tropics as an ornamental plant. The plant is immediately recognizable for its huge fan-forming banana-like leaves and is locally referred to in Magagascar by several vernacular names. "Variants" have been mentioned in the literature, but without any attempt to recognize formal taxa based on diagnostic features. In this paper, we formally describe five new species and fix the application of the name R. madagascariensis to the populations growing on the eastern coast of Madagascar, with the epitype growing in the marshy Fort-Dauphin area in the south. This paper has numerous implications for conservation biology and other domains of life sciences, due to the importance of this genus for the conservation of Madagascan ecosystems, the ornamental plant trade, as well as for its invasive status in several tropical areas.

Discovery of the first succulent bamboo (Poaceae, Bambusoideae) in a new genus from Laos' karst areas, with a unique adaptation to seasonal drought.

Lush jungle flagship species, woody bamboos (Poaceae-Bambusoideae) are famed for their synchronous flowering as well as the extensive "bamboo forests" some species can form in tropical or temperate environments. In portions of their natural distribution, Bambusoideae members developed various adaptations to seasonality in environmental parameters, such as frost or seasonal drought. A new taxon, Laobambos calcareus, described here, is extremely novel in showing the first documented case of succulence in bamboos, with its ability to seasonally vary the volume of its stem depending on the quantity of water stored. Anatomical studies presented in this paper document this specificity at the cellular level. Though no flowers or fruits are known yet, unique morphological characteristics along with an investigation of its phylogenetic affinities using molecular data show that this new taxon should belong to a new genus herein described.

Chloroplast and nuclear DNA exchanges among Begonia sect. Baryandra species (Begoniaceae) from Palawan Island, Philippines, and descriptions of five new species.

The Philippine island of Palawan is highly biodiverse. During fieldwork there in 2011 & 2014 we found five unknown species in the large genus Begonia. The species are similar in their rhizomatous stems, four-tepaled flowers, inferior two- or three-locular ovaries with bilamellate placentas, and are assignable to Begonia sect. Baryandra. Our observations support the recognition of these as five new species endemic to Palawan: B. elnidoensis, B. gironellae, B. quinquealata, B. tabonensis and B. tenuibracteata which are described here. The five new species were added to phylogenies based Bayesian analysis of nrDNA (ITS) and chloroplast DNA (ndhA, ndhF-rpl32, rpl32-trnL, trnC-trnD), along with 45 other allied ingroup species. A majority of the species show incongruent positions in the two phylogenies, with evidence of prevalent chloroplast capture. Models show chloroplast capture is more likely in plant populations with high levels of inbreeding following a reduction in selfing rate after hybridisation; we suggest that this is a possible explanation for the massive amount of chloroplast exchange seen in our phylogeny, as Begonia species often exist as small isolated populations and may be prone to inbreeding depression. Our data also indicate a level of nuclear genetic exchange between species. The high prevalence of hybrid events in Begonia is potentially an important factor in driving genomic change and species evolution in this mega-diverse genus.

The Miocene to Pleistocene colonization of the Philippine archipelago by Begonia sect. Baryandra (Begoniaceae).

PREMISE OF THE STUDY: One third of the species-rich Philippine flora is endemic, and most of the islands in the archipelago have never been connected to a continental region. We currently lack any well-sampled angiosperm phylogenies that span the archipelago, prohibiting the formation of informed hypotheses as to the evolution of this rich and highly endemic flora. METHODS: We produced time-calibrated phylogenetic trees from both nuclear (ITS) and chloroplast (ndhA intron, ndhF-rpl32 spacer, rpl32-trnL spacer, trnC-trnD spacer) regions of 41 species of Begonia sect. Baryandra, all except one endemic to the Philippines. Historical biogeography was reconstructed across the chloroplast phylogeny using a Bayesian binary method of character optimization. Comparison of phylogenies from the two genomes permitted insight into the prevalence of hybridization in the group. KEY RESULTS: The Philippine archipelago was colonized by Begonia sect. Baryandra in the late Miocene, via long-distance dispersal from western Malesia and a point of entry likely to be in the northwestern region of the archipelago. Palawan, Luzon, and Panay all bear early-branching lineages from this initial colonization. There have been Plio-Pleistocene dispersals from these islands into Borneo and Mindanao. Hybridization was common between species as evidenced by haplotype sharing and phylogenetic incongruence. CONCLUSIONS: The phylogenies show a high degree of geographic structure, which millions of years of exposure to typhoons have not blurred, showing long-term species and population stability. The recent dispersals to Mindanao are congruent with the geologically recent arrival of the island at its current latitude in the southern Philippines.

Three new species of Begonia endemic to the Puerto Princesa Subterranean River National Park, Palawan.

BACKGROUND: Begonia is a mega-diverse genus of flowering plants prone to generating micro-endemic species, especially on limestone habitats. During fieldwork in the Puerto Princesa Subterranean River National Park, Palawan (Philippines), three species were encountered which did not match any previously described from the region. RESULTS: Following morphological, anatomical, molecular phylogenetic and cytological investigation a hypothesis of three new species is supported. The three new species belong to a clade endemic to Palawan and Borneo. CONCLUSIONS: The limestone habitats in the Puerto Princesa Subterranean River National Park environs support a unique flora. The description of three new species from a small area within the park demonstrates how much remains to be discovered there, and the importance of its continued protection.

Resynchronization with left ventricle lead placement through the foramen ovale.

Left ventricle (LV) lead placement in a coronary sinus branch for cardiac resynchronization therapy may fail because of anatomical variants, phrenic nerve stimulation, and/or lead instability. We report a case of successful resynchronization from a lead inserted from the left subclavian vein and positioned through a patent foramen ovale (PFO). In conclusion, endocardial LV lead insertion through a PFO enables effective resynchronization delivery without the risks associated with a thoracotomy or atrial transseptal puncture.

Resynchronization: what if the left ventricular lead cannot reach the lateral or posterolateral wall?

BACKGROUND: The recommended left ventricular (LV) lead position for cardiac resynchronization therapy (CRT) is at the lateral or posterolateral wall. However, LV leads cannot always be implanted at this site. The objective of our study was to compare the clinical response to CRT when the LV lead could be implanted or not at the lateral or posterolateral wall. METHODS: In consecutive patients implanted with a CRT device, we documented the final position achieved by the tip of the LV lead in the left anterior oblique projection. Patients were prospectively followed for 6 months after implantation. They were defined as responders if they were alive, had gained 1 New York Heart Association (NYHA) functional class, and had not been hospitalized for heart failure. RESULTS: The study population consisted of 77 patients (56 men, 71 +/- 10 years, 62 NYHA class III, 15 NYHA class IV). The LV lead was implanted at the lateral or posterolateral wall in 54 patients (group A) and at the anterior or anterolateral wall in 23 patients (group B). At 6 months, seven patients (9%) died (all in group A). There were 37 responders (69%) in group A as compared to 22 (96%) in group B. CONCLUSIONS: The responder rate was not inferior when the LV lead was implanted at the anterior or anterolateral wall. Thus, in case of failed implantation at the lateral or posterolateral wall, positioning the LV lead in a more anterior location appears to be a reasonable alternative. Further studies are required to confirm these findings.

Where are the left ventricular leads really implanted? A study of 90 consecutive patients.

BACKGROUND: Cardiac resynchronization therapy (CRT) is a recognized treatment for severe heart failure. The recommended left ventricular (LV) lead position is at the lateral or posterolateral wall. However, LV leads cannot always be implanted at the expected site. The aim of our study was to describe in a large series of patients the anatomical position really achieved by LV leads at implant. METHOD: In consecutive patients referred for CRT, we determined the LV lead implantation success rate, the success rate for the initial target vein, and the final position achieved by the tip of the LV lead in the left and right anterior oblique projections. RESULTS: Ninety patients (66 men, 71 +/- 9 years, 20% New York Heart Association (NYHA) class IV) were referred for an LV lead implantation between September 2003 and March 2006. A LV lead could be implanted in 92% of patients. In 70%, LV leads were implanted in the initial target vein. The final location was lateral or posterolateral in 68% and anterior or anterolateral in 32% of patients. The mean procedural time was 117 +/- 42 minutes. CONCLUSIONS: LV lead implantation was achieved in 92% of patients with mean procedure duration of less than 2 hours. Nevertheless, 30% of LV leads were implanted outside of the initial target vein and 32% at the anterior or anterolateral wall. Further studies are warranted to compare the responder rate to CRT when the LV lead is at the lateral or posterolateral wall or when the LV lead is at an alternative site.

Reverse remodeling with resynchronization in an asymptomatic patient with dilated hypokinetic cardiomyopathy.

Cardiac resynchronization therapy (CRT) is a validated treatment for selected heart failure patients who remain highly symptomatic despite optimal drug treatment. Yet there is currently no indication for CRT in patients with few or no symptoms. We report a spectacular "reverse remodeling" effect after CRT in an asymptomatic patient with hypokinetic dilated myocardiopathy who needed pacing for atrio-ventricular conduction disorder. CRT was chosen to prevent deterioration of left ventricular function by conventional right apical pacing. Thus, CRT could be indicated in patients with hypokinetic dilated myocardiopathy before the appearance of symptoms.

Atrioventricular nodal reentrant tachycardia diagnosed by pacemaker electrograms.

Electrograms stored by pacemakers or implantable defibrillators enable the diagnosis of numerous atrial or ventricular arrhythmia episodes. We present the case of a patient implanted with a DDD pacemaker for sinus node dysfunction who experienced episodes of tachycardia. Atrioventricular nodal reentrant tachycardia was diagnosed by real-time analysis of electrograms during and at the onset of the tachycardia episodes. Electrophysiological study confirmed the diagnosis and led to radical treatment of the tachycardia by radiofrequency ablation of the slow pathway.