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1.
Sci Rep ; 13(1): 2207, 2023 02 07.
Article in English | MEDLINE | ID: mdl-36750620

ABSTRACT

The Andean mountains stand out for their striking species richness and endemicity that characterize many emblematic Neotropical clades distributed in or around these mountains. The radiation of the Sigmodontinae subfamily, the most diversified mammalian group in the Neotropics, has been historically related to Andean orogenesis. We aim to evaluate this interplay between geological processes and biological responses through the diversification dynamics, the biogeographical history, and the range evolution of the subfamily. For these, we built the most comprehensive phylogeny and gathered 14,836 occurrences for the subfamily. We identified one shift in the speciation rate in the genus Akodon, which suffered their Andean radiation after the arrival of non-Andean ancestors. Our biogeographic analyses show multiple dispersal paths throughout the evolution that allowed this subfamily to colonize all Neotropics. The Northern Andes and Central-Southern Andes were the most important sources of diversity. In addition, the Central-Southern Andes were the most relevant sink, receiving the highest number of lineages. The Andean region exhibited higher speciation and turnover rates than non-Andean regions. Thus, our results support the crucial role of the Andean Mountains in the Sigmodontinae radiation, acting as a "macroevolutionary cradle" and "species attractor" for several sigmodontine lineages at different times, and as a "species pump" becoming the biogeographic source of multiple widely distributed neotropical lineages. Then, complex macroevolutionary dynamics would explain these rodents' high extant Andean diversity and their wide distribution in the Neotropics.


Subject(s)
Rodentia , Sigmodontinae , Animals , Phylogeography , Arvicolinae , Phylogeny , Genetic Speciation
2.
Int J Emerg Med ; 13(1): 63, 2020 Dec 09.
Article in English | MEDLINE | ID: mdl-33297938

ABSTRACT

BACKGROUND: The objective of the study was to assess the cerebrospinal fluid (CSF) findings in COVID-19 patients. AIMS: This was an observational retrospective cohort from electronic medical records of hospitalized patients (n = 2655) with confirmed COVID-19 between February 15, 2020, and April 15, 2020, in 182 hospitals from a large health system in the USA. The review of data yielded to a total of 79 patients in 20 hospitals who had CSF analysis. METHODS: Outcomes during hospitalization, including hospital length of stay, disease severity, ventilator time, and in-hospital death were recorded. Independent variables collected included patient demographics, diagnoses, laboratory values, and procedures. RESULTS: A total of 79 patients underwent CSF analysis. Of these, antigen testing was performed in 73 patients. Ten patients had CSF analysis for general markers such as total protein, cell count, glucose, clarity, and color. Seven of the 10 cases (70%) had normal total cell count and normal white blood cell count in CSF. Sixty-three percent (5/8) had elevated total protein. Two patients had normal levels of lactate dehydrogenase (LDH) and 1 patient had significantly elevated (fourfold) neuron-specific enolase (NSE) level in CSF. CONCLUSION: Unlike bacterial infections, viral infections are less likely to cause remarkable changes in CSF glucose, cell count, or protein. Our observations showed no pleocytosis, but mild increase in protein in the CSF of the COVID-19 patients. The fourfold elevation of NSE may have diagnostic/prognostic value as a biomarker in CSF for COVID-19 patients who have altered mental status.

3.
Cureus ; 12(10): e11033, 2020 Oct 19.
Article in English | MEDLINE | ID: mdl-33214960

ABSTRACT

Neuron specific enolase (NSE) is a biomarker for neuronal injury. However, increased levels in cerebrospinal fluid (CSF) and serum is associated with the clinical outcome in patients with head injury, ischemic stroke, intracerebral hemorrhage, cardiac arrest, anoxic encephalopathy, encephalitis, brain metastasis, and status epilepticus. Recently, the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, which started in China, rapidly evolved into the coronavirus disease 2019 (COVID-19) pandemic. Patients with COVID-19 have a wide range of symptoms varying from mild upper respiratory symptoms to severe illness requiring mechanical ventilation. While coronaviruses primarily target the human respiratory system, neurological symptoms are also observed in some patients. These include symptoms such as loss of taste and olfaction and diseases like cerebrovascular disorders including ischemic stroke and hemorrhages, encephalopathies, Guillain-Barré syndrome and acute disseminated encephalomyelitis. Here we report an observation from a patient whose NSE levels increased approximately four-fold in CSF. This finding was accompanied by increased white blood cell count and elevated protein in CSF indicating neuroinflammation. Thus, we suggest that NSE may be used as a CSF biomarker in COVID-19 patients with encephalopathy.

4.
Neurol Clin Pract ; 10(4): 314-323, 2020 Aug.
Article in English | MEDLINE | ID: mdl-32983611

ABSTRACT

OBJECTIVE: To provide a review of cognitive outcomes across a full neuropsychological profile in patients who underwent laser interstitial thermal therapy (LiTT) for mesiotemporal epilepsy (mTLE). METHODS: We examined cognitive outcomes following LiTT for mTLE by reviewing a consecutive series of 26 patients who underwent dominant or nondominant hemisphere procedures. Each patient's pre- and postsurgical performance was examined for clinically significant change (>1SD improvement or decline on standardized scores), with a neuropsychologic battery that included measures of language, memory, executive functioning, and processing speed. RESULTS: Presurgical performance was largely consistent with previous research, where patients suffering from dominant hemisphere epilepsies demonstrated deficits in verbal learning and memory, whereas patients with nondominant hemisphere scored lower on visually mediated tests. Case-by-case review comparing presurgical to postsurgical scores revealed clinically significant improvement in both dominant and nondominant patients in learning and memory and other aspects of cognition such as processing speed and executive functioning. Of the few patients who did experience clinically significant decline following LiTT, a greater proportion had undergone dominant hemisphere procedures. CONCLUSIONS: Compared with the outcome literature of dominant open anterior temporal lobectomies (ATLs), where postsurgical decline has been documented in up to 40%-60% of cases, our LiTT case series exhibited a much lower incidence of postoperative language or verbal memory decline. Moreover, promising rates of postoperative improvements were also observed across multiple cognitive domains. Future studies exploring cognitive outcomes following LiTT should include comprehensive neuropsychological findings, rather than only select domains, as clinically significant change can occur in areas other than those typically associated with mesiotemporal structures.

5.
Nature ; 572(7771): 651-654, 2019 08.
Article in English | MEDLINE | ID: mdl-31413362

ABSTRACT

The origins of endothermy in birds and mammals are important events in vertebrate evolution. Endotherms can maintain their body temperature (Tb) over a wide range of ambient temperatures primarily using the heat that is generated continuously by their high basal metabolic rate (BMR)1. There is also an important positive feedback loop as Tb influences BMR1-3. Owing to this interplay between BMRs and Tb, many ecologists and evolutionary physiologists posit that the evolution of BMR and Tb must have been coupled during the radiation of endotherms3-5, changing with similar trends6-8. However, colder historical environments might have imposed strong selective pressures on BMR to compensate for increased rates of heat loss and to keep Tb constant9-12. Thus, adaptation to cold ambient temperatures through increases in BMR could have decoupled BMR from Tb and caused different evolutionary routes to the modern diversity in these traits. Here we show that BMR and Tb were decoupled in approximately 90% of mammalian phylogenetic branches and 36% of avian phylogenetic branches. Mammalian BMRs evolved with rapid bursts but without a long-term directional trend, whereas Tb evolved mostly at a constant rate and towards colder bodies from a warmer-bodied common ancestor. Avian BMRs evolved predominantly at a constant rate and without a long-term directional trend, whereas Tb evolved with much greater rate heterogeneity and with adaptive evolution towards colder bodies. Furthermore, rapid shifts that lead to both increases and decreases in BMRs were linked to abrupt changes towards colder ambient temperatures-although only in mammals. Our results suggest that natural selection effectively exploited the diversity in mammalian BMRs under diverse, often-adverse historical thermal environments.


Subject(s)
Basal Metabolism/physiology , Biological Evolution , Body Temperature/physiology , Animals , Birds/classification , Birds/metabolism , Body Temperature Regulation/physiology , Mammals/classification , Mammals/metabolism , Phylogeny
7.
PeerJ ; 7: e6955, 2019.
Article in English | MEDLINE | ID: mdl-31149405

ABSTRACT

The temperate rainforests of southern Chile, a recognized biodiversity hotspot, were significantly affected by Pleistocene glacial cycles in their southern portion and have been severely disrupted mainly due to recent human activities. Additionally, the landscape is characterized by a series of potential barriers to gene flow, such as the Chacao Channel, Cordillera de Piuche in Chiloé and both the Ancud and the Corcovado gulfs. We used mitochondrial DNA sequences and microsatellite data across several populations to evaluate the genetic variability and structure of the sigmodontine rodent Abrothrix olivacea brachiotis, one of the most common species of small mammals and an inhabitant of these biodiverse forests. Sequencing data showed that along with the recovery of high haplotype variation for this species, there was a low nucleotide diversity between haplotypes, showing no genetic differences between the Chiloé Island and continental populations in southern Chile or through any other geographic barrier in the study area. However, microsatellite data exhibited some level of population structuring. The most evident clusterings were those of the Chiloé Island and that of North Patagonia. These findings are corroborated by a barrier analysis that showed a genetic barrier in the latter areas, whereas the Chacao Channel was not a significant barrier for this rodent. Overall, the genetic variability and structure of A. o. brachiotis was concordant with historical factors, such as the Last Glacial Maximum and the presence of geographic elements that isolate populations.

8.
Sci Total Environ ; 649: 1323-1337, 2019 Feb 01.
Article in English | MEDLINE | ID: mdl-30308903

ABSTRACT

Debris talus is a very common landform in the temperate high mountain, so much so that it is the most representative of the periglacial and nival processes. This work studies debris cones in the Picos de Europa, an Atlantic mountain range in the north of the Iberian Peninsula. A detailed geomorphological map was prepared, fieldwork was carried out on the debris cone surface, the ground and air thermal regime was analyzed, and a five-year Terrestrial Laser Scan survey carried out. Annual volume changes on the surface of the debris cones were detected and related to active processes and sediment transfer. Two different behaviors were observed in each cone. Cone A is linear, with equilibrium between accumulation and sediment transfer, while Cone B is concave-convex denoting accumulation processes in the upper part deriving from the greater frequency of snow avalanches. Changes in morphology surpass 50 cm/year with most of the activity taking place in the highest and lowest areas. The presence and action of the ice on the debris slope are moderate or non-existent and freeze-thaw processes are only active on the walls at over 2000 m a.s.l. The main processes on debris cones are debris flow and creep related to snowcover, but sediment transfer on the slopes involves high intensity-low frequency (debris flow, avalanches) and high frequency-low intensity processes (creep, shift, solifluction and wasting).

9.
Evolution ; 72(5): 1124-1133, 2018 05.
Article in English | MEDLINE | ID: mdl-29624665

ABSTRACT

Among the earliest macroecological patterns documented, is the range and body size relationship, characterized by a minimum geographic range size imposed by the species' body size. This boundary for the geographic range size increases linearly with body size and has been proposed to have implications in lineages evolution and conservation. Nevertheless, the macroevolutionary processes involved in the origin of this boundary and its consequences on lineage diversification have been poorly explored. We evaluate the macroevolutionary consequences of the difference (hereafter the distance) between the observed and the minimum range sizes required by the species' body size, to untangle its role on the diversification of a Neotropical species-rich bird clade using trait-dependent diversification models. We show that speciation rate is a positive hump-shaped function of the distance to the lower boundary. The species with highest and lowest distances to minimum range size had lower speciation rates, while species close to medium distances values had the highest speciation rates. Further, our results suggest that the distance to the minimum range size is a macroevolutionary constraint that affects the diversification process responsible for the origin of this macroecological pattern in a more complex way than previously envisioned.


Subject(s)
Animal Distribution , Biological Evolution , Body Size , Passeriformes/classification , Animals , Genetic Speciation , Passeriformes/anatomy & histology , Phylogeny
10.
Zookeys ; (803): 155-160, 2018.
Article in English | MEDLINE | ID: mdl-30643488

ABSTRACT

Austrocodrusgladiogeminus sp. n. is described from southernmost South America. It is a member of the primitive subfamily Austroserphinae (Hymenoptera, Proctotrupidae), which is distributed in Oceania and South America, and is characterized from other Austrocodrus species by its relatively larger body size, the presence of long and sword-shaped ovipositor sheaths, M arising very close and distal to 1cu-a, and Cu and m-cu joining at a distance equivalent to the length of 2cu-a. We consider this species to be a Gondwanan relict. It has southernmost distribution of any proctotrupid.

11.
PeerJ ; 5: e3850, 2017.
Article in English | MEDLINE | ID: mdl-28966894

ABSTRACT

BACKGROUND: Why biodiversity is not uniformly distributed on the Earth is a major research question of biogeography. One of the most striking patterns of disparity in species distribution are the biodiversity hotspots, which generally do not fit with the distribution of relevant components of the Neotropical biota. In this study, we assess the proximal causes of the species-richness pattern of one of the most conspicuous groups of Neotropical mammals, the New World monkeys the Platyrrhini. We test two complementary hypotheses: (1) there is a historical source-sink dynamic (addressed using macroevolutionary and macroecological approaches); (2) the large number of species in the Amazon basin is due to the constraints imposed by environmental variables occurring outside this area. METHODS: We first characterize spatial patterns of species richness and biodiversity hotspots using a new, objective protocol based on probabilities. Then we evaluate the source-sink hypothesis using BioGeoBEARS analysis and nestedness analysis of species richness patterns. Complementarily, to measure how often different species pairs appear in the same sites, we used null models to estimate the checkerboard score index (C-score). Finally, we evaluate the relationship between several climatic variables and species richness through ordinary least squares (OLS) and spatial autoregressive (SAR) models, and the potential environmental constraints on the pattern. RESULTS: We found one significant cluster of high values for species richness in the Amazon basin. Most dispersal events occurred from the Amazonian subregion to other Neotropical areas. Temperature (T), discrepancy (BR), and NODF indexes show a significant nesting in the matrix ordered by species richness and available energy. The C-score observed was significantly smaller than the null expectation for all sites in the Neotropics where there are records of platyrrhine species. Ten climatic variables comprised the best-fitting model that explains species richness. OLS and SAR models show that this set of variables explains 69.9% and 64.2% of species richness, respectively. Potential of evapotranspiration is the most important variable within this model, showing a linear positive relationship with species richness, and clear lower and upper limits to the species richness distribution. DISCUSSION: We suggest that New World monkeys historically migrated from their biodiversity hotspot (energetically optimal areas for most platyrrine species) to adjacent, energetically suboptimal areas, and that the different dispersal abilities of these species, the lack of competitive interactions at a macroecological scale, and environmental constraints (i.e., energy availability, seasonality) are key elements which explain the non-uniform pattern of species richness for this clade.

12.
PeerJ ; 5: e3842, 2017.
Article in English | MEDLINE | ID: mdl-28975057

ABSTRACT

BACKGROUND: Fragmentation of native forests is a highly visible result of human land-use throughout the world. In this study, we evaluated the effects of landscape fragmentation and matrix features on the genetic diversity and structure of Oligoryzomys longicaudatus, the natural reservoir of Hantavirus in southern South America. We focused our work in the Valdivian Rainforest where human activities have produced strong change of natural habitats, with an important number of human cases of Hantavirus. METHODS: We sampled specimens of O. longicaudatus from five native forest patches surrounded by silvoagropecuary matrix from Panguipulli, Los Rios Region, Chile. Using the hypervariable domain I (mtDNA), we characterized the genetic diversity and evaluated the effect of fragmentation and landscape matrix on the genetic structure of O. longicaudatus. For the latter, we used three approaches: (i) Isolation by Distance (IBD) as null model, (ii) Least-cost Path (LCP) where genetic distances between patch pairs increase with cost-weighted distances, and (iii) Isolation by Resistance (IBR) where the resistance distance is the average number of steps that is needed to commute between the patches during a random walk. RESULTS: We found low values of nucleotide diversity (π) for the five patches surveyed, ranging from 0.012 to 0.015, revealing that the 73 sampled specimens of this study belong to two populations but with low values of genetic distance (γST ) ranging from 0.022 to 0.099. Likewise, we found that there are no significant associations between genetic distance and geographic distance for IBD and IBR. However, we found for the LCP approach, a significant positive relationship (r = 0.737, p = 0.05), with shortest least-cost paths traced through native forest and arborescent shrublands. DISCUSSION: In this work we found that, at this reduced geographical scale, Oligoryzomys longicaudatus shows genetic signs of fragmentation. In addition, we found that connectivity between full growth native forest remnants is mediated by the presence of dense shrublands and native forest corridors. In this sense, our results are important because they show how native forest patches and associated routes act as source of vector species in silvoagropecuary landscape, increasing the infection risk on human population. This study is the first approach to understand the epidemiological spatial context of silvoagropecuary risk of Hantavirus emergence. Further studies are needed to elucidate the effects of landscape fragmentation in order to generate new predictive models based on vector intrinsic attributes and landscape features.

13.
Epilepsia ; 58(5): 801-810, 2017 05.
Article in English | MEDLINE | ID: mdl-28244590

ABSTRACT

OBJECTIVE: To identify features of ablations and trajectories that correlate with optimal seizure control and minimize the risk of neurocognitive deficits in patients undergoing laser interstitial thermal therapy (LiTT) for mesiotemporal epilepsy (mTLE). METHODS: Clinical and radiographic data were reviewed from a prospectively maintained database of all patients undergoing LiTT for the treatment of mTLE at the University of Miami Hospital. Standard preoperative and postoperative evaluations, including contrast-enhanced magnetic resonance imaging (MRI) and neuropsychological testing, were performed in all patients. Laser trajectory and ablation volumes were computed both by manual tracing of mesiotemporal structures and by nonrigid registration of ablation cavities to a common reference system based on 7T MRI data. RESULTS: Among 23 patients with at least 1-year follow-up, 15 (65%) were free of disabling seizures since the time of their surgery. Sparing of the mesial hippocampal head was significantly correlated with persistent disabling seizures (p = 0.01). A lateral trajectory through the hippocampus showed a trend for poor seizure outcome (p = 0.08). A comparison of baseline and postoperative neurocognitive testing revealed areas of both improvement and worsening, which were not associated with ablation volume or trajectory. SIGNIFICANCE: At 1-year follow-up, LiTT appears to be a safe and effective tool for the treatment of mTLE, although a longer follow-up period is necessary to confirm these observations. Better understanding of the impact of ablation volume and location could potentially fine-tune this technique to improve seizure-freedom rates and associated neurologic and cognitive changes.


Subject(s)
Anterior Temporal Lobectomy/methods , Epilepsy, Temporal Lobe/surgery , Laser Therapy/methods , Neurocognitive Disorders/prevention & control , Postoperative Complications/prevention & control , Adult , Amygdala/surgery , Anterior Temporal Lobectomy/adverse effects , Brain Mapping , Epilepsy, Temporal Lobe/pathology , Female , Follow-Up Studies , Hippocampus/surgery , Humans , Male , Middle Aged , Neuropsychological Tests , Outcome Assessment, Health Care , Prospective Studies , Risk Factors , Statistics as Topic
14.
Zootaxa ; 4105(4): 339-52, 2016 Apr 21.
Article in English | MEDLINE | ID: mdl-27394783

ABSTRACT

Only two species of Didelphidae are currently recognized in Chile, the sister species Thylamys elegans, endemic of Mediterranean ecorregion and Thylamys pallidior, the inhabitant of the Puna and desert canyons. Three subspecies have been described for T. elegans: T. e. elegans, T. e. coquimbensis and T. e. soricinus. However, a recent study based on morphological analyses, synonymized T. elegans coquimbensis from the Coquimbo valleys (30-31° S) with T. pallidior and proposed that T. elegans and T. pallidior could be in sympatry at Coquimbo valleys between Fray Jorge (30°40'S) and Paiguano (30°02' S). We assess the current definition of T. e. coquimbensis and T. e. elegans, as well as this taxonomical conflict among the mouse opossums from the Coquimbo valleys through phylogenetic analyses of cytochrome b mitochondrial gene sequences. In this study, for the first time, we used specimens from the type localities of T. e. coquimbensis and T. e. elegans. In addition, we analyzed diagnostic cranial structures for this taxonomic revision. The results supported two allopatric clades, allowing us to keep the taxonomic definition of T. e. elegans and T. e. coquimbensis as phylogenetic reciprocal monophyletic clades and polyphyletic with T. pallidior. This result corroborates previous morphological analyses, which support that mouse opossums from the Coquimbo valleys are T. e. coquimbensis, thus extending its geographic distribution to the coast of Coquimbo and Atacama regions. We don´t have evidence for sympatric distribution between T. elegans and T. pallidior in the Coquimbo region.


Subject(s)
Opossums/classification , Opossums/genetics , Animal Distribution , Animal Structures/anatomy & histology , Animal Structures/growth & development , Animals , Body Size , Chile , Cytochromes b/genetics , Ecosystem , Female , Male , Opossums/anatomy & histology , Opossums/growth & development , Organ Size , Phylogeny
15.
F1000Prime Rep ; 7: 61, 2015.
Article in English | MEDLINE | ID: mdl-26097734

ABSTRACT

The purpose of this article is to review recent advances in the treatment of epilepsy. It includes five antiepileptic drugs that have been recently added to the pharmacologic armamentarium and surgical techniques that have been developed in the last few years. Finally, we review ongoing research that may have a potential role in future treatments of epilepsy.

16.
Salud tecnol. vet ; 2(2): 78-82, jul.-dic. 2014. ilus, tab
Article in Spanish | LILACS, LIPECS | ID: lil-781676

ABSTRACT

Determinar la presencia de huevos de T. canis en el suelo de Instituciones Educativas del Norte de Lima. Metodología: Se recolectó una muestra de suelo en 30 instituciones estatales educativas (IEE) de los siguientes distritos de Lima norte: Comas (n=17), Puente Piedra (n=8), Ancón (n=3) y Carabayllo (n=2). Todas las muestras se procesaron mediante la técnica de concentración por flotación. Resultados y Conclusiones: Se obtuvieron dos muestras positivas lo que representa una frecuencia 6.7%. Las IEE que resultaron positivas correspondían al distrito de Comas y Puente Piedra...


To determine the presence of Toxocara canis eggs on the ground of some Public Schools in North Lima. Methods: Thirty ground samples were collected from Public Schools in the following North Lima districts: Comas (n=17), Puente Piedra (n=8), Ancón (n= 3) and Carabayllo (n=2). Samples were processed using the Concentration by Flotation Technique. Results: Two samples positive, which represents a frequency of 6.7%. The positive samples belong to to the districts of Comas and Puente Piedra...


Subject(s)
Humans , Environmental Pollution , Parasite Egg Count , Zoonoses , Epidemiology, Descriptive , Cross-Sectional Studies , Peru
17.
PLoS One ; 9(4): e94104, 2014.
Article in English | MEDLINE | ID: mdl-24714732

ABSTRACT

Larval modes of development affect evolutionary processes and influence the distribution of marine invertebrates in the ocean. The decrease in pelagic development toward higher latitudes is one of the patterns of distribution most frequently discussed in marine organisms (Thorson's rule), which has been related to increased larval mortality associated with long pelagic durations in colder waters. However, the type of substrate occupied by adults has been suggested to influence the generality of the latitudinal patterns in larval development. To help understand how the environment affects the evolution of larval types we evaluated the association between larval development and habitat using gastropods of the Muricidae family as a model group. To achieve this goal, we collected information on latitudinal distribution, sea water temperature, larval development and type of substrate occupied by adults. We constructed a molecular phylogeny for 45 species of muricids to estimate the ancestral character states and to assess the relationship between traits using comparative methods in a Bayesian framework. Our results showed high probability for a common ancestor of the muricids with nonpelagic (and nonfeeding) development, that lived in hard bottoms and cold temperatures. From this ancestor, a pelagic feeding larva evolved three times, and some species shifted to warmer temperatures or sand bottoms. The evolution of larval development was not independent of habitat; the most probable evolutionary route reconstructed in the analysis of correlated evolution showed that type of larval development may change in soft bottoms but in hard bottoms this change is highly unlikely. Lower sea water temperatures were associated with nonpelagic modes of development, supporting Thorson's rule. We show how environmental pressures can favor a particular mode of larval development or transitions between larval modes and discuss the reacquisition of feeding larva in muricids gastropods.


Subject(s)
Biological Evolution , Ecosystem , Gastropoda/genetics , Larva/growth & development , Animal Distribution , Animals
18.
PLoS One ; 7(7): e40838, 2012.
Article in English | MEDLINE | ID: mdl-22808274

ABSTRACT

Recently, it has been proposed that the one of the main determinants of complex societies in Hymenoptera is colony size, since the existence of large colonies reduces the direct reproductive success of an average individual, given a decreased chance of being part of the reproductive caste. In this study, we evaluate colony size evolution in corbiculate bees and their relationship with the sociality level shown by these bees. Specifically i) the correlation between colony size and level of sociality considering the phylogenetic relationship to evaluate a general evolutionary tendency, and ii) the hypothetical ancestral forms of several clades within a phylogeny of corbiculate bees, to address idiosyncratic process occurring at important nodes. We found that the level of social complexity in corbiculate bees is phylogenetically correlated with colony size. Additionally, another process is invoked to propose why colony size evolved concurrently with the level of social complexity. The study of this trait improves the understanding of the evolutionary transition from simple to complex societies, and highlights the importance of explicit probabilistic models to test the evolution of other important characters involved in the origin of eusociality.


Subject(s)
Bees/genetics , Bees/physiology , Biological Evolution , Social Behavior , Animals , Logistic Models , Markov Chains , Models, Genetic , Phylogeny
19.
PLoS One ; 7(4): e34654, 2012.
Article in English | MEDLINE | ID: mdl-22509339

ABSTRACT

At the macroevolutionary level, one of the first and most important hypotheses that proposes an evolutionary tendency in the evolution of body sizes is "Cope's rule". This rule has considerable empirical support in the fossil record and predicts that the size of species within a lineage increases over evolutionary time. Nevertheless, there is also a large amount of evidence indicating the opposite pattern of miniaturization over evolutionary time. A recent analysis using a single phylogenetic tree approach and a bayesian based model of evolution found no evidence for Cope's rule in extant mammal species. Here we utilize a likelihood-based phylogenetic method, to test the evolutionary trend in body size, which considers phylogenetic uncertainty, to discern between Cope's rule and miniaturization, using extant Oryzomyini rodents as a study model. We evaluated body size trends using two principal predictions: (a) phylogenetically related species are more similar in their body size, than expected by chance; (b) body size increased (Cope's rule)/decreased (miniaturization) over time. Consequently the distribution of forces and/or constraints that affect the tendency are homogenous and generate this directional process from a small/large sized ancestor. Results showed that body size in the Oryzomyini tribe evolved according to phylogenetic relationships, with a positive trend, from a small sized ancestor. Our results support that the high diversity and specialization currently observed in the Oryzomyini tribe is a consequence of the evolutionary trend of increased body size, following and supporting Cope's rule.


Subject(s)
Body Size , Evolution, Molecular , Sigmodontinae/genetics , Sigmodontinae/physiology , Animals , Bayes Theorem , Likelihood Functions , Phylogeny , Time Factors , Uncertainty
20.
Epilepsy Res ; 98(2-3): 260-3, 2012 Feb.
Article in English | MEDLINE | ID: mdl-22015002

ABSTRACT

The outcomes of adult epilepsy patients prescribed lacosamide for additional seizure control. Responders were defined as having at least a 50% decrease in seizure frequency Sixty-seven patients were evaluated. Forty-six out of 67 patients (69%) were responders. Twelve of 14 patients not taking sodium channel-acting AEDs were responders (86%) and 34/53 patients taking sodium channel-acting AEDs were responders (64%) (difference not significant).


Subject(s)
Acetamides/therapeutic use , Anticonvulsants/therapeutic use , Epilepsy/drug therapy , Product Surveillance, Postmarketing , Adolescent , Adult , Aged , Aged, 80 and over , Epilepsy/epidemiology , Female , Humans , Lacosamide , Male , Middle Aged , Treatment Outcome , Young Adult
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