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1.
Mol Phylogenet Evol ; 192: 108008, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38181828

ABSTRACT

Two main landscapes emerge from the Guiana Shield: the highlands to the west called the Pantepui region and the Amazonian lowlands to the east, both harbouring numerous endemic species. With 32 currently recognized species, the genus Anomaloglossus stands out among Neotropical frogs as one that diversified only within the Guiana Shield both in the highlands and the lowlands. We present a time-calibrated phylogeny obtained by using combined mitogenomic and nuclear DNA, which suggests that the genus originates from Pantepui where extant lineages started diversifying around 21 Ma, and subsequently (ca. 17 Ma) dispersed during the Miocene Climatic Optimum to the lowlands of the eastern Guiana Shield where the ability to produce endotrophic tadpoles evolved. Further diversification within the lowlands in the A. stepheni group notably led to an evolutionary reversal toward exotrophy in one species group during the late Miocene, followed by reacquisition of endotrophy during the Pleistocene. These successive shifts of reproductive mode seem to have accompanied climatic oscillations. Long dry periods might have triggered evolution of exotrophy, whereas wetter climates favoured endotrophic forms, enabling colonization of terrestrial habitats distant from water. Acquisition, loss, and reacquisition of endotrophy makes Anomaloglossus unique among frogs and may largely explain the current species diversity. The micro evolutionary processes involved in these rapid shifts of reproductive mode remain to be revealed.


Subject(s)
Anura , Ecosystem , Animals , Anura/genetics , Phylogeny , Phylogeography
2.
Sci Rep ; 13(1): 11674, 2023 07 19.
Article in English | MEDLINE | ID: mdl-37468518

ABSTRACT

Coralsnakes of the genus Micrurus are a diverse group of venomous snakes ranging from the southern United States to southern South America. Much uncertainty remains over the genus diversity, and understanding Micrurus systematics is of medical importance. In particular, the widespread Micrurus nigrocinctus spans from Mexico throughout Central America and into Colombia, with a number of described subspecies. This study provides new insights into the phylogenetic relationships within M. nigrocinctus by examining sequence data from a broad sampling of specimens from Mexico, Guatemala, Honduras, Nicaragua, Costa Rica, and Panama. The recovered phylogenetic relationships suggest that M. nigrocinctus is a species complex originating in the Pliocene and composed of at least three distinct species-level lineages. In addition, recovery of highly divergent clades supports the elevation of some currently recognized subspecies to the full species rank while others may require synonymization.


Subject(s)
Venoms , United States , Phylogeny , Central America , Panama , Mexico
3.
Nutrients ; 13(1)2020 Dec 22.
Article in English | MEDLINE | ID: mdl-33375014

ABSTRACT

Obesity is more prevalent in black South African women than men. However, little is known about the nutrient patterns associated with body composition indices in black African women. Principle Component Analysis (PCA) was applied to 25 nutrients derived from quantified food frequency questionnaires (QFFQs) in 498 middle aged black South African women. Three nutrient patterns, the plant driven, animal driven and Vitamin C, sugar and potassium driven nutrient patterns, accounted for 59% of the variance of nutrient intake. Linear models of the body composition parameters as outcome variables indicated that a standard deviation increase in the animal driven nutrient pattern was significantly associated with increases in body mass index (BMI) (1.29 kg·m-2 (95% CI, 0.54-2.04; p = 0.001), subcutaneous adipose tissue (SAT) (26.30 cm2 (7.97-44.63); p = 0.005), visceral adipose tissue (VAT) (9.88 cm2 (5.13-14.63); p < 0.001), VAT/SAT ratio (0.01 (0.00-0.02); p = 0.018), whole body fat mass index (0.74 kg·m-2 (0.25-1.22); p = 0.003), and whole body lean mass index (0.53 kg·m-2 (0.23-0.83); p = 0.001). An increase in plant driven nutrient pattern was significantly associated with an increase in SAT of 20.45 cm2 (0.47-40.43); p = 0.045. This study demonstrates that animal driven nutrient pattern, characterised by the consumption of more animal protein and fat nutrients, similar to the western diet is associated with increased body fat and lean mass.


Subject(s)
Black People , Body Composition , Nutrients , Adipose Tissue , Adult , Body Mass Index , Cross-Sectional Studies , Energy Intake , Female , Humans , Intra-Abdominal Fat , Middle Aged , Obesity , South America , Subcutaneous Fat , Surveys and Questionnaires
4.
Zootaxa ; 4820(1): zootaxa.4820.1.7, 2020 Jul 27.
Article in English | MEDLINE | ID: mdl-33056085

ABSTRACT

Anomaloglossus is a species-rich genus of frogs endemic to the Guiana Shield that still harbours several unnamed species. According to a recent integrative taxonomic survey, the A. stepheni species group includes five valid nominal species and at least four putatively unnamed species, two in Brazil and two in Suriname. In this paper, we describe the two species from Suriname based on adult and tadpole morphology as well as their calls and natural history. Both have exotrophic tadpoles transported by the male to small water bodies. These two new species differ from each other and from other congeners in body size, colouration pattern, call characteristics and breeding sites. Both have narrow distributions and should be considered Endangered according to IUCN criteria.


Subject(s)
Anura , Animals , Larva , Male , Suriname
5.
Int J Mol Sci ; 21(14)2020 Jul 14.
Article in English | MEDLINE | ID: mdl-32674288

ABSTRACT

Some organic compounds are known to self-assemble into nanotubes in solutions, but the packing of the molecules into the walls of the tubes is known only in a very few cases. Herein, we study two compounds forming nanotubes in alkanes. They bear a secondary alkanamide chain linked to a benzoic acid propyl ester (HUB-3) or to a butyl ester (HUB-4). They gel alkanes for concentrations above 0.2 wt.%. The structures of these gels, studied by freeze fracture electron microscopy, exhibit nanotubes: for HUB-3 their external diameters are polydisperse with a mean value of 33.3 nm; for HUB-4, they are less disperse with a mean value of 25.6 nm. The structure of the gel was investigated by small- and wide-angle X-ray scattering. The evolution of the intensities show that the tubes are metastable and transit slowly toward crystals. The intensities of the tubes of HUB-4 feature up to six oscillations. The shape of the intensities proves the tubular structure of the aggregates, and gives a measurement of 20.6 nm for the outer diameters and 11.0 nm for the inner diameters. It also shows that the electron density in the wall of the tubes is heterogeneous and is well described by a model with three layers.


Subject(s)
Amides/chemistry , Gels/chemistry , Nanotubes/chemistry , Alkanes/chemistry , Microscopy, Electron/methods , Particle Size , X-Ray Diffraction/methods
6.
Zootaxa ; 4576(3): zootaxa.4576.3.2, 2019 Apr 03.
Article in English | MEDLINE | ID: mdl-31715747

ABSTRACT

Anomaloglossus is a species-rich genus of frogs endemic to the Guiana Shield that still harbors several unnamed species. Within the A. stepheni species group (which includes four valid nominal species), A. baeobatrachus has an uncertain taxonomic status, notably because the holotype was an unvouchered specimen depicted in a popular journal. Another member of this group, A. leopardus, was only superficially described, lacking information on the sex of specimens in the type series and on advertisement call. Therefore, these two taxa need clarifications in order to allow the description of the extant undescribed species. In this paper, we redescribe A. baeobatrachus based on newly collected material from the species type locality and provide information about its reproductive ecology. We also provide an amended definition of A. leopardus using newly collected material from its type locality. These two species form a clade along with a third species from the Eastern Guiana Shield, which is also described herein. The reproductive biology of A. baeobatrachus and A. stepheni is very similar. Both species have endotrophic and nidicolous tadpoles, despite being distantly related, suggesting independent evolution of this breeding mode. The new species and A. leopardus, on the other hand, have exotrophic tadpoles.


Subject(s)
Anura , Reproduction , Animals , Guyana , Larva
7.
Curr Biol ; 29(22): R1170-R1171, 2019 11 18.
Article in English | MEDLINE | ID: mdl-31743668

ABSTRACT

Tepuis are Precambrian sandstone tabletop mountains in South America that can reach up to ∼3,000 m in elevation. Their highest summits are both physiographically and ecologically isolated from the surrounding upland savannah and lush tropical rainforest, and they face particularly hostile, challenging environmental conditions [1,2] (Figure 1A). Taxa thriving on high tepui summits must adapt to resource-limited and highly competitive ecosystems. The toad genus Oreophrynella is exclusively found on tepui slopes and summits [3] and is particularly well-adapted to the tepui top environment. We here report on an unanticipated and possibly large-scale predation on this endemic toad by non-bioluminescent firefly larvae.


Subject(s)
Bufonidae/parasitology , Fireflies/parasitology , Altitude , Animals , Anura , Bufonidae/physiology , Ecology , Ecosystem , Fireflies/metabolism , Larva/parasitology , Phylogeny , Predatory Behavior/physiology , Rainforest , South America
8.
Mol Phylogenet Evol ; 130: 315-329, 2019 01.
Article in English | MEDLINE | ID: mdl-30366086

ABSTRACT

Neotropical sipo snakes (Chironius) are large diurnal snakes with a long tail and big eyes that differ from other Neotropical snakes in having 10 or 12 dorsal scale rows at midbody. The 22 currently recognized species occur from Central America south to Uruguay and northeastern Argentina. Based on the largest geographical sampling to date including ∼90% of all species, we analyzed one nuclear and three mitochondrial genes using phylogenetic methods to (1) test the monophyly of Chironius and some of its widely distributed species; (2) identify lineages that could represent undescribed species; and (3) reconstruct ancestral distributions. Our best hypothesis placed C. grandisquamis (Chocoan Rainforest) + C. challenger (Pantepui) as sister to all other species. Based on phylogeny and geographic distribution, we identified 14 subclades as putative species within Chironius fuscus, C. multiventris (including C. foveatus and C. laurenti), C. monticola, and C. exoletus. Under current taxonomy, these species show nearly twice as much genetic diversity as other species of Chironius for ND4. Biogeographical analyses using BioGeoBEARS suggest that current distribution patterns of Chironius species across South America resulted from multiple range expansions. The MRCA of the clade C. challenger + C. grandisquamis was most likely distributed over the Pantepui region, the Andes, and the Chocoan Rainforest, whereas the remaining lineages probably evolved from an Amazonian ancestor.


Subject(s)
Colubridae/classification , Colubridae/genetics , Genetic Variation , Phylogeny , Phylogeography , Tropical Climate , Animals , Base Sequence , South America , Time Factors
9.
Zootaxa ; 4379(1): 1-23, 2018 Feb 13.
Article in English | MEDLINE | ID: mdl-29689971

ABSTRACT

A large portion of the amphibian species occurring in Amazonia remains undescribed. A recent study on species delineation in Anomaloglossus, a genus endemic to the Guiana Shield, demonstrated the existence of two undescribed species previously identified as A. degranvillei, which we describe herein. In addition to divergence at the molecular level, these two new taxa are also distinguished by subtle morphological characters and substantial differences in the advertisement calls (note length, dominant frequency, note structure). One species occurs in the hilly lowlands of north-eastern French Guiana and is mainly distinguished from its closest relatives by a small body size (15.9-18.8 mm in males) and by vocalisations characterized by the emission of short notes of 0.09 s on average. The other species is only known from the Itoupé Massif in southern French Guiana and is mainly distinguished from its closest relatives by a moderate body size (19.4-20.4 mm in males) and by vocalisations characterized by the emission of long notes of 0.23 s on average. We also provide amended definitions for two previously described species in the A. degranvillei species group: A. degranvillei, which is endemic to a few massifs in central French Guiana, and A. surinamensis, which is distributed throughout Suriname and French Guiana. The new species described here and A. degranvillei have very narrow ranges within French Guiana and seem to have rapidly declined during the last decade. Therefore, we suggest A. degranvillei and A. dewynteri to be considered as "Critically Endangered" and A. blanci as "Vulnerable" according to the IUCN standards.


Subject(s)
Anura , Animals , Body Size , French Guiana , Guyana , Male , Suriname
10.
Mol Phylogenet Evol ; 112: 158-173, 2017 07.
Article in English | MEDLINE | ID: mdl-28438699

ABSTRACT

Lack of resolution on species boundaries and distribution can hamper inferences in many fields of biology, notably biogeography and conservation biology. This is particularly true in megadiverse and under-surveyed regions such as Amazonia, where species richness remains vastly underestimated. Integrative approaches using a combination of phenotypic and molecular evidence have proved extremely successful in reducing knowledge gaps in species boundaries, especially in animal groups displaying high levels of cryptic diversity like amphibians. Here we combine molecular data (mitochondrial 16S rRNA and nuclear TYR, POMC, and RAG1) from 522 specimens of Anomaloglossus, a frog genus endemic to the Guiana Shield, including 16 of the 26 nominal species, with morphometrics, bioacoustics, tadpole development mode, and habitat use to evaluate species delineation in two lowlands species groups. Molecular data reveal the existence of 18 major mtDNA lineages among which only six correspond to described species. Combined with other lines of evidence, we confirm the existence of at least 12 Anomaloglossus species in the Guiana Shield lowlands. Anomaloglossus appears to be the only amphibian genus to have largely diversified within the eastern part of the Guiana Shield. Our results also reveal strikingly different phenotypic evolution among lineages. Within the A. degranvillei group, one subclade displays acoustic and morphological conservatism, while the second subclade displays less molecular divergence but clear phenotypic divergence. In the A. stepheni species group, a complex evolutionary diversification in tadpole development is observed, notably with two closely related lineages each displaying exotrophic and endotrophic tadpoles.


Subject(s)
Anura/classification , Anura/genetics , Genetic Variation , Acoustics , Animals , Bayes Theorem , Brazil , DNA, Mitochondrial/genetics , DNA, Ribosomal/genetics , Ecosystem , Larva/growth & development , Likelihood Functions , Phylogeny , Principal Component Analysis , Reproduction , Species Specificity
11.
Ann Hepatol ; 15(6): 834-845, 2016.
Article in English | MEDLINE | ID: mdl-27740516

ABSTRACT

 Background. Patient race and ethnicity have historically impacted HCV treatment response. This phase 3 study evaluated daclatasvir with peginterferon-alfa-2a/ribavirin (pegIFN alfa-2a/RBV) in treatment-naive black/African American (AA), Latino, and white non-Latino patients with chronic HCV genotype 1 infection. MATERIAL AND METHODS: In this single-arm, open-label study, 246 patients received daclatasvir plus pegIFN alfa-2a and weight-based RBV. Patients with an extended rapid virologic response (eRVR; undetectable HCV-RNA at treatment weeks 4 and 12) received 24 weeks of treatment; those without eRVR received an additional 24 weeks of treatment with pegIFN alfa-2a/RBV. The primary endpoint was sustained virologic response at post-treatment week 12 (SVR12; HCV-RNA < 25 IU/mL) compared with the cohort historical rate. RESULTS: Most patients were IL28B non-CC (84.4% black/AA; 77.6% Latino) genotype 1a-infected (72.7%; 81.3%), with HCV-RNA ≥ 800,000 IU/mL (81.3%; 64.5%). SVR12 rates were 50.8% (65/128; 95% confidence interval [CI], 42.1-59.4) for black/AA and 58.9% (63/107; 95% CI, 49.6-68.2) for Latino patients. The majority (55.5%; 58.9%) received 24 weeks treatment; rapid reductions (> 4-log10) in HCV-RNA levels were observed. Only 60.9% (78/128) of black/AA and 63.6% (68/107) of Latino patients completed treatment. On-treatment serious adverse events (SAEs) occurred in 21 patients. Discontinuations due to adverse events (AEs) occurred in 9 black/AA and 6 Latino patients. CONCLUSION: SVR12 rates for black/AA (50.8%) and Latino (58.9%) cohorts treated with daclatasvir plus pegIFN alfa-2a/RBV and the lower bound of the 95% CIs were higher than the estimated historical control (black/AA, 26% SVR; Latino, 36% SVR) treated with pegIFN alfa-2a/RBV. These data support daclatasvir use in all-oral direct-acting antiviral combinations.


Subject(s)
Antiviral Agents/therapeutic use , Black or African American , Hepacivirus/drug effects , Hepatitis C, Chronic/drug therapy , Hispanic or Latino , Imidazoles/therapeutic use , Interferon-alpha/therapeutic use , Polyethylene Glycols/therapeutic use , Ribavirin/therapeutic use , Administration, Oral , Adult , Aged , Antiviral Agents/adverse effects , Biomarkers/blood , Carbamates , Drug Therapy, Combination , Female , Genotype , Hepacivirus/genetics , Hepacivirus/pathogenicity , Hepatitis C, Chronic/diagnosis , Hepatitis C, Chronic/ethnology , Hepatitis C, Chronic/virology , Humans , Imidazoles/adverse effects , Interferon-alpha/adverse effects , Male , Middle Aged , Polyethylene Glycols/adverse effects , Puerto Rico , Pyrrolidines , RNA, Viral/blood , Recombinant Proteins/adverse effects , Recombinant Proteins/therapeutic use , Ribavirin/adverse effects , Time Factors , Treatment Outcome , United States/epidemiology , Valine/analogs & derivatives , Viral Load , Young Adult
12.
Zootaxa ; 4084(1): 79-104, 2016 Feb 24.
Article in English | MEDLINE | ID: mdl-27394251

ABSTRACT

We used molecular and morphological data to investigate the hidden diversity within the Hypsiboas semilineatus species group, and more specifically within H. geographicus, an allegedly widespread species in northern South America. As a result, the identity of H. geographicus was clarified, several candidate species were detected and one of them, from the eastern Guiana Shield, is described herein as a preliminary step to resolve the taxonomy of the group. Hypsiboas diabolicus sp. nov. is mainly distinguished from closely-related species by an acuminate snout in lateral view, well-developed webbing between fingers and toes, and unspotted carmine/crimson colouration on the concealed surfaces of legs, feet and hands in life. The tadpole of the new species is described and is characterized by a large A-2 gap, a mostly single row of large marginal papillae, and a dark brown to black colouration. We also describe the advertisement call of the new species, which is defined as a soft call consisting of short clusters of 2-3 chuckles with a dominant frequency ranging between 1.11-1.19 kHz. Hypsiboas diabolicus sp. nov. is currently known only from the eastern Guiana Shield, and is probably endemic to that region. The new species' range overlaps broadly with another candidate species referred to as H. aff. semilineatus 1. Our preliminary results stress out a high cryptic diversity in that species group and the need for a formal redescription of Hypsiboas geographicus based on more topotypic material than what is currently available  to properly sort out the taxonomic status of several lineages in that clade.


Subject(s)
Anura/classification , Biodiversity , Animal Distribution , Animal Structures/anatomy & histology , Animal Structures/growth & development , Animals , Anura/anatomy & histology , Anura/genetics , Anura/growth & development , Body Size , Female , Guyana , Male , Organ Size , Phylogeny , Vocalization, Animal
13.
Zootaxa ; 3926(2): 191-210, 2015 Mar 05.
Article in English | MEDLINE | ID: mdl-25781778

ABSTRACT

We describe two new species of Anomaloglossus from Roraima State, Brazil, that are likely endemic to single mountains currently isolated among lowland forest and savanna ecosystems. The first species, Anomaloglossus tepequem sp. nov. was collected in 1986 and 1992 along a single stream at >500 m elevation on a tepui-like mountain named Tepequém, but was not detected during recent investigations. It is mainly diagnosed from other Anomaloglossus species by its well developed foot webbing, immaculate cream abdomen colouration and small body size (males: 18.2-20.1 mm, females: 21.7-24.5). The second species, Anomaloglossus apiau sp. nov. was found along several streams between 500 and 1400 m elevation on Serra do Apiaú, and is mainly diagnosed from congeners by its weakly webbed feet, males with swollen third finger and ventrolateral stripe formed by white dots, and its advertisement call; a long trill (up to almost 40 s) consisting of pairs of very short pulses. The discovery of these two apparently microendemic species suggests that additional Anomaloglossus species remain to be described in the Guiana Shield. Both species should be considered critically endangered given their seemingly reduced range size, association with highland habitat, and the anthropogenic pressure they currently face.


Subject(s)
Anura/classification , Animal Distribution , Animal Structures/anatomy & histology , Animal Structures/growth & development , Animals , Anura/anatomy & histology , Anura/growth & development , Anura/physiology , Body Size , Brazil , Ecosystem , Endangered Species , Female , Male , Organ Size , Vocalization, Animal
14.
PLoS One ; 9(9): e103958, 2014.
Article in English | MEDLINE | ID: mdl-25208078

ABSTRACT

Species distributed across vast continental areas and across major biomes provide unique model systems for studies of biotic diversification, yet also constitute daunting financial, logistic and political challenges for data collection across such regions. The tree frog Dendropsophus minutus (Anura: Hylidae) is a nominal species, continentally distributed in South America, that may represent a complex of multiple species, each with a more limited distribution. To understand the spatial pattern of molecular diversity throughout the range of this species complex, we obtained DNA sequence data from two mitochondrial genes, cytochrome oxidase I (COI) and the 16S rhibosomal gene (16S) for 407 samples of D. minutus and closely related species distributed across eleven countries, effectively comprising the entire range of the group. We performed phylogenetic and spatially explicit phylogeographic analyses to assess the genetic structure of lineages and infer ancestral areas. We found 43 statistically supported, deep mitochondrial lineages, several of which may represent currently unrecognized distinct species. One major clade, containing 25 divergent lineages, includes samples from the type locality of D. minutus. We defined that clade as the D. minutus complex. The remaining lineages together with the D. minutus complex constitute the D. minutus species group. Historical analyses support an Amazonian origin for the D. minutus species group with a subsequent dispersal to eastern Brazil where the D. minutus complex originated. According to our dataset, a total of eight mtDNA lineages have ranges >100,000 km2. One of them occupies an area of almost one million km2 encompassing multiple biomes. Our results, at a spatial scale and resolution unprecedented for a Neotropical vertebrate, confirm that widespread amphibian species occur in lowland South America, yet at the same time a large proportion of cryptic diversity still remains to be discovered.


Subject(s)
Anura/genetics , Biodiversity , Animals , DNA, Mitochondrial/genetics , Electron Transport Complex IV/genetics , Evolution, Molecular , Phylogeography
15.
Malar J ; 12: 152, 2013 May 04.
Article in English | MEDLINE | ID: mdl-23641802

ABSTRACT

Resistance to artemisinin casts a shadow on the fight against malaria. The importance of illegal gold miners and of malaria in isolated regions of French Guiana constitutes a threat that endangers the fight against malaria in the Amazon. The hurdles of French laws and the remoteness of the territory from France make it impossible for the system to adapt to the problem of total inaccessibility of an important part of the malaria problem. Transmission is high in these areas and gold miners self-medicate with erratic regimens of artemisinin combinations, thus creating perfect conditions for the emergence of resistance. What needs to be done is being done, but within the limits of national law, with some results. However, facing the same difficult problem, Suriname shows more flexibility and is doing much better than French Guiana despite having lower resources. Local authorities in French Guiana cannot overrule the laws that block appropriate malaria care from reaching a third of malaria-exposed persons. Thus the health authorities in France should take immediate calibrated legislative and financial measures to avoid a predictable disaster.


Subject(s)
Antimalarials/pharmacology , Antimalarials/therapeutic use , Artemisinins/pharmacology , Artemisinins/therapeutic use , Drug Resistance , Malaria/drug therapy , Malaria/parasitology , Europe , French Guiana , Health Policy , Humans
16.
Zootaxa ; 3750: 569-86, 2013 Dec 23.
Article in English | MEDLINE | ID: mdl-25113717

ABSTRACT

We describe a new Pristimantis from French Guiana, northern South America, which is mainly distinguished from known phenotypically related congeners (i.e. species from the polyphyletic unistrigatus species group) occurring at low and middle elevations in the Guiana Shield by the combination of a distinct tympanum, a lower ratio of tibia vs. hand length, a reddish groin region, and a distinct advertisement call consisting of clusters of generally four short notes. The new species inhabits pristine primary forests on the slopes of isolated massifs reaching more than 400 m elevation, and seems not to occur below ca. 200 m above sea level. Such a sharp altitudinal limit suggests a strong influence of thermal variation on the distribution of the species, and therefore a potential sensitivity to climate change. With only nine isolated populations documented so far, the new species should be prioritized for conservation. Historical climate fluctuations during the Quaternary are likely responsible for the distribution pattern of the new species. 


Subject(s)
Anura/classification , Animal Distribution , Animal Structures/anatomy & histology , Animals , Anura/anatomy & histology , Anura/physiology , Ecosystem , Female , Guyana , Male , Vocalization, Animal
18.
Mol Phylogenet Evol ; 65(2): 547-61, 2012 Nov.
Article in English | MEDLINE | ID: mdl-22842094

ABSTRACT

Documenting the Neotropical amphibian diversity has become a major challenge facing the threat of global climate change and the pace of environmental alteration. Recent molecular phylogenetic studies have revealed that the actual number of species in South American tropical forests is largely underestimated, but also that many lineages are millions of years old. The genera Phyzelaphryne (1 sp.) and Adelophryne (6 spp.), which compose the subfamily Phyzelaphryninae, include poorly documented, secretive, and minute frogs with an unusual distribution pattern that encompasses the biotic disjunction between Amazonia and the Atlantic forest. We generated >5.8 kb sequence data from six markers for all seven nominal species of the subfamily as well as for newly discovered populations in order to (1) test the monophyly of Phyzelaphryninae, Adelophryne and Phyzelaphryne, (2) estimate species diversity within the subfamily, and (3) investigate their historical biogeography and diversification. Phylogenetic reconstruction confirmed the monophyly of each group and revealed deep subdivisions within Adelophryne and Phyzelaphryne, with three major clades in Adelophryne located in northern Amazonia, northern Atlantic forest and southern Atlantic forest. Our results suggest that the actual number of species in Phyzelaphryninae is, at least, twice the currently recognized species diversity, with almost every geographically isolated population representing an anciently divergent candidate species. Such results highlight the challenges for conservation, especially in the northern Atlantic forest where it is still degraded at a fast pace. Molecular dating revealed that Phyzelaphryninae originated in Amazonia and dispersed during early Miocene to the Atlantic forest. The two Atlantic forest clades of Adelophryne started to diversify some 7 Ma minimum, while the northern Amazonian Adelophryne diversified much earlier, some 13 Ma minimum. This striking biogeographic pattern coincides with major events that have shaped the face of the South American continent, as we know it today.


Subject(s)
Anura/classification , Conservation of Natural Resources , Phylogeny , Animals , Bayes Theorem , Cell Nucleus/metabolism , Ecosystem , North America , Phylogeography , Sequence Alignment , Sequence Analysis, DNA , South America
19.
Emerg Infect Dis ; 18(8): 1346-9, 2012 Aug.
Article in English | MEDLINE | ID: mdl-22840888

ABSTRACT

We investigated chloroquine sensitivity to Plasmodium falciparum in travelers returning to France and Canada from Haiti during a 23-year period. Two of 19 isolates obtained after the 2010 earthquake showed mixed pfcrt 76K+T genotype and high 50% inhibitory concentration. Physicians treating malaria acquired in Haiti should be aware of possible chloroquine resistance.


Subject(s)
Chloroquine/pharmacology , Drug Resistance/genetics , Earthquakes , Plasmodium falciparum/drug effects , Travel , Adolescent , Adult , Aged , Animals , Antimalarials/pharmacology , Antimalarials/therapeutic use , Canada/epidemiology , Child , Child, Preschool , Chloroquine/therapeutic use , Disasters , Female , France/epidemiology , Genotype , Haiti , Humans , Infant , Malaria, Falciparum/drug therapy , Malaria, Falciparum/parasitology , Male , Membrane Transport Proteins/genetics , Middle Aged , Parasitic Sensitivity Tests , Plasmodium falciparum/genetics , Plasmodium falciparum/isolation & purification , Protozoan Proteins/genetics , Young Adult
20.
J Chromatogr A ; 1259: 167-78, 2012 Oct 12.
Article in English | MEDLINE | ID: mdl-22520638

ABSTRACT

Plants belonging to the Lippia genus have been widely used in ethnobotany throughout South and Central America and in tropical Africa as foods, medicines, sweeteners and in beverage flavouring. Various taxonomic problems involving some genera from Verbenaceae, including Lippia, have been reported. In this study, the metabolite profiling of fifteen extracts of various organs of six Lippia species was performed and compared using UHPLC-PDA-TOF-MS. Fourteen phenolic compounds that were previously isolated from L. salviaefolia Cham. and L. lupulina Cham. were used as references. The annotation of the remaining LC peaks was based on concomitant online high mass accuracy measurements and subsequent molecular formula assignments following these different steps: (i) elimination of non-coherent putative molecular formulae by heuristic filtering, (ii) verification of the occurrence of remaining molecular formulae in databases, (iii) cross search with reported compounds in the Lippia genus, (iv) match with reported UV spectra, (v) estimation of the chromatographic retention behaviour based on the log P parameter of reference compounds. This strategy is generic and time-saving, avoids isolation/purification procedures, enables an efficient LC peak annotation of most of the studied compounds and is well adapted for plant chemotaxonomic studies. Within this study, the interconversion of four flavanone glucoside isomers was additionally highlighted by analytical HPLC isolation and immediate analysis using fast UHPLC gradients. Dereplication results and hierarchical data analysis demonstrated that L. salviaefolia, L. balansae, L. velutina and L. sidoides displayed significant chemical similarities, while the compositions of L. lasiocalicyna and L. lupulina differed substantially.


Subject(s)
Chromatography, High Pressure Liquid/methods , Lippia/chemistry , Mass Spectrometry/methods , Plant Extracts/chemistry , Cluster Analysis , Flavanones/analysis , Flavanones/chemistry , Lippia/metabolism , Metabolome , Metabolomics/methods
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