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1.
Zookeys ; 1060: 183-192, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34690508

RESUMO

For 80 years, there were no sightings of the Andean frog, Telmatobiushalli, due to the ambiguity with which its type locality was described ("warm spring near Ollagüe", northern Chile). The type specimens were collected during the International High Altitude Expedition to Chile (IHAEC) in 1935 and were subsequently described in 1938. In 2018 and 2020, two studies independently reported the rediscovery of the species, but they reached different conclusions about its identity and geographic distribution. In fact, the populations identified as T.halli in those studies are more phylogenetically related to other species than to each other, so they clearly do not belong to the same taxon. Although the study of 2020 is more in line with the geographic information of the description, it does not consider some bibliographic details and the transport limitations of the IHAEC. Here, based on a detailed analysis of the chronicles of the IHAEC and other bibliographic sources, I first refute the proposals of the 2018 and 2020 studies and then provide a possible solution. The combined information from the chronicles indicates that the type locality of T.halli is found at the sources of the Loa River, a different place from those identified in the two previous studies. By also incorporating geographic information of the time, I conclude that its true type locality is Miño, an abandoned mining camp located near the origin of the Loa River, where currently no populations of the genus have been described.

2.
Zookeys ; 1079: 1-33, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35068957

RESUMO

Telmatobiushalli was the first representative of its genus to be described exclusively for Chile, yet for 85 years no new individuals could be located due to the vagueness with which its type locality was described. The type series was collected by one of the members of the International High Altitude Expedition to Chile (IHAEC) of 1935. Recently, three studies successively claimed to have located the type locality in different places. The third study proved, according to the chronicles of the IHAEC, that the actual locality is Miño, at the origin of the Loa River, where currently there are no published records of Telmatobius. In this study, additional documentary antecedents and graphic material are provided that corroborate that Miño is indeed the type locality of T.halli. Additionally, the recently rediscovered Telmatobius population from Miño and the environment it inhabits are described. The external characteristics of the frogs are consistent with the description of T.halli. Furthermore, molecular phylogenetic analyses were performed that showed that T.halli, T.dankoi, and T.vilamensis, all known only from their type localities in Chile, comprise a clade without internal resolution. A detailed comparison of the diagnoses of the three species revealed that the few phenotypic differences between these taxa were based on characteristics that vary widely within and between populations of the genus, hence their conspecificity is proposed. The implications of this synonymy for the taxonomy, biogeography, and conservation of the Telmatobius from the extreme south of its distribution in Chile are discussed.

3.
BMC Zool ; 6(1): 25, 2021 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-37170376

RESUMO

BACKGROUND: The causes of geographic variation of body size in ectotherms have generally been attributed to environmental variables. Research in amphibians has favored mechanisms that involve water availability as an explanation for the geographic variation of body size. However, there are few studies at intraspecific level on amphibians that inhabit desert or semi-desert environments, where hydric restrictions are stronger. Here, we describe and inquire as to the causes of the geographic variation of body size in the semi-desert toad Rhinella atacamensis, a terrestrial anuran that is distributed over 750 km along a latitudinal aridity gradient from the southern extreme of the Atacama Desert to the Mediterranean region of central Chile. We measured the snout-vent length of 315 adults from 11 representative localities of the entire distribution of the species. Then, using an information-theoretic approach, we evaluate whether the data support eight ecogeographic hypotheses proposed in literature. RESULTS: Rhinella atacamensis exhibits a gradual pattern of decrease in adult body size towards the north of its distribution, where the climate is more arid, which conforms to a Bergmann's cline. The best model showed that the data support the mean annual precipitation as predictor of body size, favoring the converse water availability hypothesis. CONCLUSIONS: Most studies in amphibians show that adult size increases in arid environments, but we found a converse pattern to expected according to the hydric constraints imposed by this type of environment. The evidence in R. atacamensis favors the converse water availability hypothesis, whose mechanism proposes that the foraging activity determined by the precipitation gradient has produced the clinal pattern of body size variation. The variation of this trait could also be affected by the decreasing productivity that exists towards the north of the species distribution. In addition, we found evidence that both pattern and mechanism are independent of sex. Lastly, we suggest that behavioral traits, such as nocturnal habits, might also play an important role determining this differential response to aridity. Therefore, the support for the converse water availability hypothesis found in this study shows that amphibians can respond in different ways to water restrictions imposed by arid environments.

4.
Artigo em Inglês | MEDLINE | ID: mdl-31905031

RESUMO

The genus Alsodes is the most diverse amphibian taxon of southern Andes, where a series of endemic species occur from north to south (∼33° to 48°30'S), mainly on the western slopes (Chile), with little overlap of geographic ranges. In this study, we describe a new population of Alsodes from the western slopes of the Andes (Fundo El Rosario, 36°52'S), located in a section of this mountain range where it is not clear which congeneric species inhabit. Phylogenetic analyses show that this population presents a mix of mitochondrial DNA related to three nominal species, A. hugoi, A. igneus and A. pehuenche, although the last is mainly present. However, the population presents external characteristics attributable to A. hugoi and A. igneus, differing notably from A. pehuenche. The population inhabits a stream surrounded by temperate deciduous forests at 1130 m elevation, an environment similar to that of A. hugoi and A. igneus, but very different from that of A. pehuenche (high Andean steppe environments between 2000 and 2500 m). This finding represents an enigma from the evolutionary and biogeographical point of view, because it might involve hybridization and/or introgression phenomena between more than two species. As the taxonomic status of this population cannot be determined with the available genetic and morphological evidence, we speculate about its probable origin, taking into account the scarce knowledge of the geographic distributions of the species of Alsodes in the area.


Assuntos
Animais Congênicos/genética , Anuros/genética , DNA Mitocondrial/genética , Genética Populacional , Genoma Mitocondrial/genética , Animais , Evolução Biológica , Chile , Variação Genética/genética , Filogenia
5.
Zookeys ; 863: 107-152, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31341395

RESUMO

The genus Eupsophus (ground frogs) inhabits exclusively the temperate forests of southern South America (Chile and Argentina). The current delimitation of the genus was reached in the late 1970s, when only two species were recognized, but since then the number of described species steadily increased, reaching a maximum of 11 by 2012. Subsequent studies that applied explicit species delimitation approaches decreased the number of species to six in 2017 and raised it again to 11 the following year, including an undescribed putative species. Despite these taxonomic changes, the two species groups traditionally recognized, roseus and vertebralis, have been maintained. Another recent contribution to the taxonomy of the genus was the explicit recognition of the extremely high level of external phenotypic variation exhibited by species of the roseus group, which undermines the utility of some diagnostic characters. Here we provide a critical review of the extensive taxonomic and systematic literature on the genus over the last six decades, to examine the evidence behind the recurrent taxonomic changes and advances in its systematics. We also update and complete a 2017 review of geographic information, provide additional qualitative observations of external characters commonly used in the diagnoses of species of the roseus group, and reassess the phylogenetic position of a putative new species from Tolhuaca (Chile), which was not included in the last species delimitation study. The present review shows that: 1) there is no congruence between the patterns of phenotypic and genetic/phylogenetic differentiation among species of both groups; 2) in the roseus group, the intraspecific variation in some external characters is as high as the differences described among species; 3) there is little morphological and bioacoustic differentiation within species groups, and inconsistencies in the chromosomal evidence at the genus level; 4) under the latest taxonomic proposal (2018), species of the roseus group still lack consistent and reliable diagnoses and their distribution limits are poorly defined; and 5) the population from Tolhuaca represents an additional undescribed species under the most recent taxonomic framework. Finally, we discuss the implications of these findings for the taxonomy and biogeography of the genus, pointing out some areas that require further research to understand their patterns and processes of diversification.

6.
Zootaxa ; 4438(2): 283-298, 2018 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-30313145

RESUMO

Liolaemus audituvelatus (Núñez Yáñez 1983) and L. manueli (Núñez, Navarro, Garín, Pincheira-Donoso Meriggio 2003) are endemic species of the Atacama Desert of northern Chile that belong to the montanus group. Both species are considered cryptic from each other and can only be distinguished by their distribution ranges and karyotypes. Originally, there was a wide separation zone between their known distribution ranges, but later collections reduced the gap from 430 km to only 150 km. In this study, we review the geographic information about both species and report new localities within the distribution gap, where species identification becomes difficult. We performed a molecular phylogenetic analysis and applied several species delimitation methods to reassess the taxonomic status of both nominal species and new intermediate populations. Our analyses support the placement of L. manueli in the synonymy of L. audituvelatus. We discuss the biogeographic and conservation implications of this new synonymy.


Assuntos
Lagartos , Filogenia , Animais , Chile , Cariótipo , Cariotipagem
7.
Mol Phylogenet Evol ; 119: 128-143, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29111477

RESUMO

Phylogenomic approaches offer a wealth of data, but a bewildering diversity of methodological choices. These choices can strongly affect the resulting topologies. Here, we explore two controversial approaches (binning genes into "supergenes" and inclusion of only rapidly evolving sites), using new data from hyloid frogs. Hyloid frogs encompass ∼53% of frog species, including true toads (Bufonidae), glassfrogs (Centrolenidae), poison frogs (Dendrobatidae), and treefrogs (Hylidae). Many hyloid families are well-established, but relationships among these families have remained difficult to resolve. We generated a dataset of ultraconserved elements (UCEs) for 50 ingroup species, including 18 of 19 hyloid families and up to 2214 loci spanning >800,000 aligned base pairs. We evaluated these two general approaches (binning, rapid sites only) based primarily on their ability to recover and strongly support well-established clades. Data were analyzed using concatenated likelihood and coalescent species-tree methods (NJst, ASTRAL). Binning strongly affected inferred relationships, whereas use of only rapidly evolving sites did not (indicating ∼87% of the data contributed little information). The optimal approaches for maximizing recovery and support of well-established clades were concatenated likelihood analysis and the use of a limited number of naive bins (statistical binning gave more problematic results). These two optimal approaches converged on similar relationships among hyloid families, and resolved them with generally strong support. The relationships found were very different from most previous estimates of hyloid phylogeny, and a new classification is proposed. The new phylogeny also suggests an intriguing biogeographical scenario, in which hyloids originated in southern South America before radiating throughout the world.


Assuntos
Anuros/classificação , Loci Gênicos , Genômica/métodos , Filogenia , Animais , Sequência Conservada/genética , Funções Verossimilhança , Análise de Sequência de DNA , Especificidade da Espécie
8.
PLoS One ; 12(8): e0181026, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28809924

RESUMO

One of the most characteristic and abundant amphibian taxa of South American temperate forests is Eupsophus. The ten currently recognized species of the genus have been divided in two species groups, roseus and vertebralis, but most of them, eight, belong to the roseus group. Recent phylogeographic and phylogenetic studies have suggested that species diversity of the roseus group could be underestimated. An examination of the literature shows that species of the roseus group exhibit high levels of variation in their external characteristics, particularly those used as diagnostic characters, which compromises their taxonomy and hinders their field recognition. High levels of variation were also observed in several new populations of the roseus group discovered in southern Chile (36°-40°S), which could not be identified to the species level by their external characteristics. On the other hand, the literature reveals a scarse karyotype differentiation and a high bioacoustic uniformity among the species of the roseus group. We performed a Bayesian phylogenetic analysis using mitochondrial and nuclear genes to reevaluate the species diversity of the roseus group, including all the nominal species of Eupsophus and new populations. This analysis was complemented with three species delimitation approaches, General Mixed Yule Coalescent, multi-rate Poisson Tree Process and Automatic Barcode Gap Discovery. We favored a conservative delimitation of only four species for the roseus group, a result more consistent with the distribution of pairwise genetic distances, and the available chromosome and bioacoustic evidence. The four recognized lineages, which have nearly completely allopatric distributions, are named after the earliest nominal species that they include, but because high levels of phenotypic variation, they are not diagnosable by consistent differences in external morphology. We discuss the implications of this new proposal for the taxonomy and conservation of the genus, and the possible causes of the difficulty to estimate its species diversity.


Assuntos
Anuros/classificação , Florestas , Animais , Anuros/genética , Teorema de Bayes , Especiação Genética , Fenótipo , Filogenia , Análise de Sequência de DNA , América do Sul , Especificidade da Espécie
9.
Rev. dor ; 17(supl.1): 98-106, 2016.
Artigo em Inglês | LILACS | ID: lil-795166

RESUMO

ABSTRACT BACKGROUND AND OBJECTIVES: Distress, allied to neuropathic pain persistence and its refractory nature, often leads patients to accept invasive procedures. Neuropathic pain control is a major medical challenge requiring approaches and decisions especially based on effectiveness, risks and costs. This study aimed at reviewing these aspects related to major invasive procedures. CONTENTS: Major invasive procedures to control neuropathic pain are presented. Initially, classically reversible anesthetic blocks; then invasive neuromodulation techniques using electric current application and the magnetic field generated by it becomes a target to be stimulated, inhibited or modified in the nervous system (central, peripheral or autonomic); and, finally, ablative procedures including anesthetic methods administering neurolytic agents rather than anesthetics and neurosurgeries using different methods to injure the nervous system to control painful neuropathic discomfort. CONCLUSION: Patients eligible to invasive procedures to control neuropathic pain have, in addition to pain itself, a mixed distress including the collection of repeated delusions at every treatment failure. They have reserved prognosis with regard to total cure and, unfortunately, relieve obtained with invasive treatment in general does not reach persistent and high rates. In such adverse situation, these partial results of decreasing original pain intensity may be interpreted as acceptable, provided the impact on final quality of life is positive. Maybe, the rare exceptions are good results obtained with typical idiopathic/cryptogenic neuralgias ironically excluded from the stricter interpretation of the new pathophysiologic classification of neuropathic pains.


RESUMO JUSTFICATIVA E OBJETIVOS: O sofrimento aliado à persistência e refratariedade da dor neuropática frequentemente leva seu portador a aceitar tratamentos invasivos. O controle da dor neuropática representa um desafio médico importante necessitando adoção de condutas e decisões baseadas, principalmente, em efetividade, riscos e custos. O escopo deste estudo foi a revisão desses aspectos relacionados aos principais procedimentos invasivos CONTEÚDO: São apresentados os principais procedimentos invasivos utilizados para o controle da dor neuropática. Inicialmente, os bloqueios anestésicos, classicamente reversíveis; depois as técnicas de neuromodulação invasiva que utilizam a aplicação de corrente elétrica e o campo magnético por ela gerado em alvos a serem estimulados, inibidos ou modificados, no sistema nervoso (central, periférico ou autônomo); e, finalmente, os procedimentos ablativos que incluem os métodos anestésicos que administram agentes neurolíticos ao invés de anestésicos, e, as neurocirurgias que utilizam métodos diversos de produção de lesões no sistema nervoso para o controle do desconforto doloroso neuropático. CONCLUSÃO: Os pacientes que se apresentam como candidatos a receberem indicações de procedimentos invasivos para controle de dores neuropáticas, possuem além do inerente à própria dor, sofrimento misto, que inclui a coleção de desilusões reiteradas a cada insucesso de tratamento. Possuem prognóstico reservado no que tange a plena cura, e, infelizmente, o alívio obtido com o tratamento invasivo, em geral, não atinge taxas persistentes e elevadas. Nessa situação tão adversa esses resultados parciais de redução da intensidade da dor original possam ser interpretados como aceitáveis desde que o impacto na qualidade de vida final seja positivo. Talvez, as raras exceções, recaiam sobre os bons resultados obtidos com as neuralgias típicas, idiopáticas/criptogenéticas, ironicamente, excluídas da interpretação mais rígida da nova classificação fisiopatológica das dores neuropáticas.

10.
Zootaxa ; 3915(4): 540-50, 2015 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-25662142

RESUMO

Based on morphological and molecular evidence (mitochondrial and nuclear sequences) we describe a new species of spiny-chest frog, Alsodes cantillanensis, from central Chile (around 34°S). The type locality, Quebrada Infiernillo, is located in the Coastal Range at approximately 65 km from Santiago (Metropolitan Region), the capital of Chile. The distribution of the new species is included entirely in that of A. nodosus (32-36°S approximately), which was identified as the sister taxon according to molecular phylogenetic analyses. Moreover, both species are sympatric in the type locality. The new species was found in a Nothofagus macrocarpa relict forest potentially threatened by gold mining activities. We identify other threats for its conservation and some biological data needed for understanding the evolution of this species. This discovery reveals the scarce knowledge about biogeography, evolution and ecology of spiny-chest frogs from central Chile. 


Assuntos
Anuros/classificação , Distribuição Animal , Estruturas Animais/anatomia & histologia , Estruturas Animais/crescimento & desenvolvimento , Animais , Anuros/anatomia & histologia , Anuros/genética , Anuros/crescimento & desenvolvimento , Tamanho Corporal , Chile , Ecossistema , Feminino , Masculino , Tamanho do Órgão , Filogenia
11.
Rev. méd. Minas Gerais ; 24(supl.3)jan.-jun. 2014.
Artigo em Português | LILACS-Express | LILACS | ID: lil-719993

RESUMO

A incidência de pacientes dependentes de drogas está aumentando. As substâncias ilícitas de consumo mais comuns são cocaína, maconha, álcool e heroína, embora o uso do crack tenha se tornado cada vez mais frequente, tornando-se um problema comum nos hospitais que atendem emergências. O efeito agudo e a longo prazo do abuso de drogas pode complicar o manejo anestésico. Muitas vezes esses pacientes não sãoidentificados no pré-operatório, por tratar-se de cirurgia de emergência ou omissão de informação. Esses pacientes demandam vigilância contínua e perspicácia do anestesiologista para evitar sérias complicações perioperatórias. Neste artigo são apresentados os principais problemas relacionados ao uso da cocaína e do crack, bem como a melhor abordagem perioperatória. Durante o procedimento anestésico são utilizados vários medicamentos de ação central que interagem com outras substâncias como a cocaína, tornando predizer o tipo de resposta apresentado pelos pacientes que fazem uso desse tipo de droga. Isso torna a anestesia nesses pacientes um verdadeiro desafio para o anestesiologista que, portanto, deve conhecer as alterações fisiopatológicas para melhor abordar esses pacientes e diminuir a morbimortalidade.


The incidence of drug dependent patients is increasing. The most common consumption among illicit substances includes cocaine, marijuana, alcohol, and heroin, however, the use of crack has become increasingly frequent and a common problem in hospitals that tend to emergencies. The acute and long-term effects of drug abuse can complicate the anesthetic management. These patients are often not identified preoperatively because they are in need of emergency surgery or due to information omission. These patients require continuous vigilance and insight from the anesthesiologist to avoid serious perioperative complications. This article presents the main problems related to the use of cocaine and crack, as well as the best perioperative approach. During the anesthetic procedure, several centrally acting medications that interact with other substances like cocaine is used making it difficult to predict the type of responses from the patients who make use of these drugs. Thus, anesthesia in these patientsis a real challenge to the anesthesiologist who must therefore be aware of the pathophysiological alterations to best address these patients and decrease morbidity and mortality.

12.
Rev Esc Enferm USP ; 46 Spec No: 16-23, 2012 Oct.
Artigo em Português | MEDLINE | ID: mdl-23250253

RESUMO

Disability related to chronic low back pain (CLBP) is a complex and multidimensional phenomenon. The aim of the study was to identify the prevalence of disability and factors associated with disability outcome in 177 CLBP adults. Respondents were recruited from three health care service centers and answered questions from: Demographic Identification Form, Oswestry Disability Index, Chronic Pain Self-efficacy Scale, Tampa Scale Kinesiophobia, Beck Depression Inventory, and the Revised Piper Fatigue Scale. The prevalence of disability among the respondents was 65% (95% CI: 57.5 - 72.0), and disability was moderate to severe in 80.7% of them. The multiple regression model identified three factors as independently associated with disability: work situation, low self-efficacy and depression. The factors identified to be associated with disability are modifiable. Interventions such as work relocation, depression treatment and re-conceptualization of self-efficacy may have an important impact in preventing and reducing disability in chronic low back pain patients.


Assuntos
Dor Crônica/complicações , Dor Crônica/epidemiologia , Pessoas com Deficiência , Dor Lombar/complicações , Dor Lombar/epidemiologia , Adolescente , Adulto , Idoso , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Adulto Jovem
13.
Rev. Esc. Enferm. USP ; 46(spe): 16-23, out. 2012. tab
Artigo em Português | LILACS, BDENF - Enfermagem | ID: lil-659825

RESUMO

A incapacidade relacionada à dor lombar crônica (DLC) é um fenômeno complexo e multifatorial. O objetivo desse estudo foi identificar a prevalência e os fatores associados à incapacidade em pacientes com dor lombar crônica. Estudo transversal com amostra composta por 177 pacientes com DLC, de três serviços de saúde; que responderam ao formulário com dados demográficos, ao Inventário de Depressão de Beck, às Escalas Oswestry Disability Index, de autoeficácia para dor crônica, Tampa de Cinesiofobia e de Fadiga de Piper. A prevalência de incapacidade foi de 65% (IC95%: 57,5 - 72,0) e era de moderada a grave em 80,7% dos pacientes. O modelo de regressão múltipla identificou três fatores independentemente associados à incapacidade: ausência de trabalho remunerado, autoeficácia baixa e depressão. Os fatores associados à incapacidade identificados são modificáveis. Intervenções como recolocação no trabalho, tratamento para a depressão e reconceitualização da crença de autoeficácia podem ter um impacto importante na prevenção e redução de incapacidade.


Disability related to chronic low back pain (CLBP) is a complex and multidimensional phenomenon. The aim of the study was to identify the prevalence of disability and factors associated with disability outcome in 177 CLBP adults. Respondents were recruited from three health care service centers and answered questions from: Demographic Identification Form, Oswestry Disability Index, Chronic Pain Self-efficacy Scale, Tampa Scale Kinesiophobia, Beck Depression Inventory, and the Revised Piper Fatigue Scale. The prevalence of disability among the respondents was 65% (95% CI: 57.5 - 72.0), and disability was moderate to severe in 80.7% of them. The multiple regression model identified three factors as independently associated with disability: work situation, low self-efficacy and depression. The factors identified to be associated with disability are modifiable. Interventions such as work relocation, depression treatment and re-conceptualization of self-efficacy may have an important impact in preventing and reducing disability in chronic low back pain patients.


La discapacidad relacionada con el dolor lumbar crónico (DLC) es complejo y multifactorial. El objetivo fue identificar la prevalencia y factores asociados a la discapacidad en pacientes con DLC. Estudio transversal con 177 pacientes de tres servicios de salud; que respondieron al formulario con los datos demográficos, Inventario de Depresión de Beck, Escala de discapacidad de Oswestry, autoeficacia para el dolor crónico, Tampa kinesiophobia and Piper fatiga. La prevalencia de la discapacidad fue del 65% (IC 95%: 57,5 a 72,0) y de moderada a severa en 80,7% de los pacientes. El modelo de regresión se identificó tres factores independientemente asociados con la discapacidad: la falta de trabajo, baja autoeficacia y la depresión. Los factores identificados son modificables. Intervenciones como el trabajo de sustitución, el tratamiento de la depresión y la reconceptualización de la creencia de la autoeficacia puede tener un impacto importante en la prevención y reducción de la discapacidad.


Assuntos
Adolescente , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem , Dor Crônica/complicações , Dor Crônica/epidemiologia , Pessoas com Deficiência , Dor Lombar/complicações , Dor Lombar/epidemiologia , Estudos Transversais , Prevalência
14.
J Otolaryngol Head Neck Surg ; 40(2): 93-103, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21453644

RESUMO

OBJECTIVE: Some patients with the syndrome of mitochondrial diabetes and deafness (MIDD) have a m.3243A>G mutation of the MTTL1 gene encoding transfer ribonucleic acid for the amino acid leucine (tRNALeu(UUR)). One of our MIDD patients inspired us to propose an integrated view on how a single mutation of the mitochondrial deoxyribonucleic acid (DNA) affects both the glucose metabolism and the inner ear physiology. DESIGN: (a) Study of mitochondrial DNA in a patient with MIDD. (b) REVIEW OF THE LITERATURE on the impact of the m.3243A>G mutation on glucose metabolism and on the physiology of the hearing process. SETTINGS: Outpatient diabetes and nutrition department and molecular nutrition laboratory. METHODS: (a) Polymerase chain reaction followed by restriction fragment analysis identified the m.3243A>G mutation. (b) REVIEW OF THE LITERATURE from 1994 to 2009. RESULTS: (a) Molecular study: the m.3243A>G mutation was detected with an appreciable level of heteroplasmy. (b) REVIEW OF THE LITERATURE: the strial marginal cells located near the organ of Corti fulfill two characteristics: they are rich in mitochondria, and their dysfunction may produce neurosensorial deafness by means of a reduction in the potassium ion concentration of the endolymph. CONCLUSIONS: The m.3243A>G mutation not only underlies a dysfunction of the insulin-producing beta cell of the pancreas but also results in a reduction in adenosine triphosphate production of the strial marginal cells of the inner ear, thus diminishing the energy (in the form of potassium ion gradient) needed for the outer hair cells of the organ of Corti to amplify the soundwaves, particularly at high frequencies.


Assuntos
DNA Mitocondrial/genética , Surdez/fisiopatologia , Diabetes Mellitus Tipo 1/genética , Perda Auditiva Neurossensorial/genética , Doenças Mitocondriais/genética , Mutação Puntual , Estria Vascular/fisiologia , Surdez/complicações , Surdez/genética , Diabetes Mellitus Tipo 1/complicações , Fenômenos Eletrofisiológicos , Feminino , Células Ciliadas Auditivas Externas/fisiologia , Perda Auditiva Neurossensorial/complicações , Perda Auditiva Neurossensorial/fisiopatologia , Humanos , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , Canais de Potássio/fisiologia
15.
Arq Neuropsiquiatr ; 68(3): 433-51, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20602051

RESUMO

UNLABELLED: The use of neuromodulation as a treatment for major depressive disorder (MDD) has recently attracted renewed interest due to development of other non-pharmacological therapies besides electroconvulsive therapy (ECT) such as transcranial magnetic stimulation (TMS), transcranial direct current stimulation (tDCS), deep brain stimulation (DBS), and vagus nerve stimulation (VNS). METHOD: We convened a working group of researchers to discuss the updates and key challenges of neuromodulation use for the treatment of MDD. RESULTS: The state-of-art of neuromodulation techniques was reviewed and discussed in four sections: [1] epidemiology and pathophysiology of MDD; [2] a comprehensive overview of the neuromodulation techniques; [3] using neuromodulation techniques in MDD associated with non-psychiatric conditions; [4] the main challenges of neuromodulation research and alternatives to overcome them. DISCUSSION: ECT is the first-line treatment for severe depression. TMS and tDCS are strategies with a relative benign profile of side effects; however, while TMS effects are comparable to antidepressant drugs for treating MDD; further research is needed to establish the role of tDCS. DBS and VNS are invasive strategies with a possible role in treatment-resistant depression. In summary, MDD is a chronic and incapacitating condition with a high prevalence; therefore clinicians should consider all the treatment options including invasive and non-invasive neuromodulation approaches.


Assuntos
Transtorno Depressivo Maior/terapia , Terapia por Estimulação Elétrica/métodos , Eletroconvulsoterapia/métodos , Estimulação Magnética Transcraniana/métodos , Brasil , Estimulação Encefálica Profunda/métodos , Transtorno Depressivo Maior/fisiopatologia , Humanos , Escalas de Graduação Psiquiátrica , Estimulação do Nervo Vago/métodos
16.
Arq. neuropsiquiatr ; 68(3): 433-451, June 2010. tab
Artigo em Inglês | LILACS | ID: lil-550281

RESUMO

The use of neuromodulation as a treatment for major depressive disorder (MDD) has recently attracted renewed interest due to development of other non-pharmacological therapies besides electroconvulsive therapy (ECT) such as transcranial magnetic stimulation (TMS), transcranial direct current stimulation (tDCS), deep brain stimulation (DBS), and vagus nerve stimulation (VNS). METHOD: We convened a working group of researchers to discuss the updates and key challenges of neuromodulation use for the treatment of MDD. RESULTS: The state-of-art of neuromodulation techniques was reviewed and discussed in four sections: [1] epidemiology and pathophysiology of MDD; [2] a comprehensive overview of the neuromodulation techniques; [3] using neuromodulation techniques in MDD associated with non-psychiatric conditions; [4] the main challenges of neuromodulation research and alternatives to overcome them. DISCUSSION: ECT is the first-line treatment for severe depression. TMS and tDCS are strategies with a relative benign profile of side effects; however, while TMS effects are comparable to antidepressant drugs for treating MDD; further research is needed to establish the role of tDCS. DBS and VNS are invasive strategies with a possible role in treatment-resistant depression. In summary, MDD is a chronic and incapacitating condition with a high prevalence; therefore clinicians should consider all the treatment options including invasive and non-invasive neuromodulation approaches.


O uso de técnicas de neuromodulação para o tratamento do transtorno depressivo maior (TDM) tem despertado um renovado interesse nos últimos anos com o desenvolvimento de outras intervenções não-farmacólogicas além da eletroconvulsoterapia (ECT), como a estimulação magnética transcraniana (EMT), a estimulação transcraniana por corrente continua (ETCC), a estimulação cerebral profunda (DBS) e a estimulação de nervo vago (VNS). MÉTODO: Nós organizamos um grupo de trabalho com vários pesquisadores para discutir os avanços recentes e os principais desafios para o uso da neuromodulação no tratamento do TDM. RESULTADOS: O estado-da-arte da neuromodulação foi revisado e discutido em quatro seções: [1] epidemiologia e fisiopatologia do TDM; [2] uma revisão das técnicas de neuromodulação; [3] o uso das técnicas de neuromodulação na depressão que ocorre associada ou em virtude de condições não-psiquiátricas; [4] os principais desafios da pesquisa na neuromodulação e alternativas para superá-los. DISCUSSÃO: ECT é o tratamento de primeira linha para depressão grave. EMT e ETCC são estratégias com um perfil benigno de efeitos adversos; contudo, enquanto os efeitos da EMT são comparáveis ao das drogas antidepressivas para o tratamento da TDM, a eficácia da ETCC ainda precisa ser estabelecida por mais pesquisas clínicas. DBS e VNS são intervenções invasivas com um papel possível para a depressão refratária. Em resumo, TDM é uma condição crônica, incapacitante e de alta prevalência; portanto na prática clínica todas as opções de tratamento possíveis, incluindo as farmacológicas e não-farmacológicas, devem ser consideradas.


Assuntos
Humanos , Transtorno Depressivo Maior/terapia , Terapia por Estimulação Elétrica/métodos , Eletroconvulsoterapia/métodos , Estimulação Magnética Transcraniana/métodos , Brasil , Estimulação Encefálica Profunda/métodos , Transtorno Depressivo Maior/fisiopatologia , Escalas de Graduação Psiquiátrica , Estimulação do Nervo Vago/métodos
17.
Clin J Pain ; 25(8): 691-5, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19920718

RESUMO

OBJECTIVE: Based on evidence showing that electrical stimulation of the nervous system is an effective method to decrease chronic neurogenic pain, we aimed to investigate whether the combination of 2 methods of electrical stimulation-a method of peripheral stimulation [transcutaneous electrical nerve stimulation (TENS)] and a method of noninvasive brain stimulation [transcranial direct current stimulation (tDCS)]-induces greater pain reduction as compared with tDCS alone and sham stimulation. METHODS: We performed a preliminary, randomized, sham-controlled, crossover, clinical study in which 8 patients were randomized to receive active tDCS/active TENS ("tDCS/TENS" group), active tDCS/sham TENS ("tDCS" group), and sham tDCS/sham TENS ("sham" group) stimulation. Assessments were performed immediately before and after each condition by a blinded rater. RESULTS: The results showed that there was a significant difference in pain reduction across the conditions of stimulation (P=0.006). Post hoc tests showed significant pain reduction as compared with baseline after the tDCS/TENS condition [reduction by 36.5% (+/-10.7), P=0.004] and the tDCS condition [reduction by 15.5% (+/-4.9), P=0.014], but not after sham stimulation (P=0.35). In addition, tDCS/TENS induced greater pain reduction than tDCS (P=0.02). CONCLUSIONS: The results of this pilot study suggest that the combination of TENS with tDCS has a superior effect compared with tDCS alone.


Assuntos
Encéfalo/fisiologia , Terapia por Estimulação Elétrica , Manejo da Dor , Estimulação Elétrica Nervosa Transcutânea , Adulto , Idoso , Idoso de 80 Anos ou mais , Braço , Doença Crônica , Terapia Combinada , Método Duplo-Cego , Terapia por Estimulação Elétrica/efeitos adversos , Determinação de Ponto Final , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Medição da Dor , Estimulação Elétrica Nervosa Transcutânea/efeitos adversos
18.
Am J Obstet Gynecol ; 199(6): e6-7, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19084092

RESUMO

Existing therapies for vulvodynia are inadequate. Because vulvodynia has a pathophysiology similar to chronic pain, central nervous system dysfunction may underlie this painful disorder, and noninvasive methods of neuromodulation may prove highly effective. We report a case of severe, medically refractory vulvodynia that responded remarkably to treatment with transcranial direct current stimulation.


Assuntos
Córtex Cerebral , Terapia por Estimulação Elétrica/métodos , Manejo da Dor , Doenças da Vulva/terapia , Doença Crônica , Feminino , Seguimentos , Humanos , Israel , Pessoa de Meia-Idade , Dor/diagnóstico , Medição da Dor , Satisfação do Paciente , Medição de Risco , Índice de Gravidade de Doença , Resultado do Tratamento , Doenças da Vulva/diagnóstico
19.
J Clin Anesth ; 20(7): 521-7, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19019663

RESUMO

STUDY OBJECTIVE: To investigate the effects of single-injection femoral nerve block (FNB) in postoperative pain after total knee replacement (TKR) and anterior cruciate ligament (ACL) reconstruction. DESIGN: Prospective, randomized, double-blind study. PATIENTS: 96 ASA physical status I, II, and III patients, scheduled for TKR or ACL reconstruction. INTERVENTIONS: All patients received a standard spinal anesthetic, then were randomly divided into three treatment groups as follows: Group B (n = 30) received an FNB with 40 mL of 0.25% bupivacaine containing epinephrine, 1:200,000; Group R (n = 32) received an FNB with 40 mL of 0.25% ropivacaine; and Group C (n = 28) received no FNB. MEASUREMENTS: The following clinical outcomes were assessed at up to 6 hours (T1), 6 to 10 hours (T2), and 10 to 24 hours (T3) after spinal anesthesia was given: visual analog scale (VAS) for pain, both at rest and on movement (no or mild pain, moderate pain, or severe pain); morphine use; sensory block in the femoral, obturator, and lateral femoral cutaneous nerve dermatomes; and motor block of the femoral and obturator nerves. MAIN RESULTS: Except for VAS during rest and on movement at time T3, there were more Group C patients who experienced moderate or severe pain than those who had no pain or mild pain, when compared with Groups R and B. Sensory block in the femoral and lateral femoral cutaneous nerve dermatomes did not differ between Groups R and B at any times. However, sensory block in the obturator nerve dermatome was lower in Group R than Group B only at T3. We observed a lower, significant use of morphine at T2 when comparing Groups R and B with Group C. No Group R patient and about 30% of Group B patients remained with motor block of femoral and obturator nerves at T3. Except for frequency of nausea, which was highest in Group C, the frequency of other side effects was similar among the three groups. CONCLUSIONS: Femoral nerve block using 0.25% ropivacaine or 0.25% bupivacaine is an effective method of postoperative analgesia after TKR and ACL reconstruction, particularly for the first 10 hours after spinal anesthesia.


Assuntos
Amidas/administração & dosagem , Anestésicos Locais/administração & dosagem , Bupivacaína/administração & dosagem , Bloqueio Nervoso/métodos , Dor Pós-Operatória/prevenção & controle , Amidas/efeitos adversos , Anestésicos Locais/efeitos adversos , Ligamento Cruzado Anterior/cirurgia , Artroplastia do Joelho , Bupivacaína/efeitos adversos , Método Duplo-Cego , Feminino , Nervo Femoral , Humanos , Masculino , Pessoa de Meia-Idade , Atividade Motora/efeitos dos fármacos , Medição da Dor/métodos , Satisfação do Paciente , Estudos Prospectivos , Ropivacaina , Fatores de Tempo , Resultado do Tratamento
20.
Rev. otorrinolaringol. cir. cabeza cuello ; 67(3): 217-221, dic. 2007. ilus
Artigo em Espanhol | LILACS | ID: lil-480510

RESUMO

Introducción: En la evaluación de la patología vestibular habitualmente se utiliza la prueba calórica clásica de Fitzgerald y Hallpike (PCC). Sin embargo, esta sólo evalúa la función del nervio vestibular superior a través de la estimulación del canal semicircular lateral. La prueba calórica mínima (PCM) permite evaluar tanto la función del nervio vestibular superior como del nervio vestibular inferior a través de la estimulación del canal semicircular lateral y posterior respectivamente. Se desconoce el real impacto de la PCM en la evaluación clínica de pacientes con sintomatología vestibular. Objetivo: Cuantificar la utilidad diagnóstica de la PCM en pacientes con sintomatología vestibular. Material y método: Estudio diagnóstico transversal. Se obtuvo la sensibilidad y especificidad de la PCM al comparar la respuesta del canal semicircular lateral en la PCM con la prueba calórica convencional. Se evaluó en cuántos casos la información sobre la función del nervio vestibular inferior aportada por la PCM fue relevante en el diagnóstico vestibular. Resultados: Se estudió a 44 pacientes. Tanto la sensibilidad como la especificidad de la PCM para detectar patología al estimular el canal semicircular lateral fue de 93 por ciento (IC95 por ciento: 84 por ciento-100 por ciento y 80 por ciento-100 por ciento respectivamente). En 16 por ciento (N =7) de los casos la PCM detectó patología del nervio vestibular inferior con PCC normal. Conclusiones: La PCM es un examen complementario útil en la evaluación de pacientes con sintomatología vestibular, puesto que tiene una alta sensibilidad y especificidad para detectar patología del nervio vestibular superior a través de la estimulación del canal semicircular lateral y además, aporta información sobre el estado del nervio vestibular inferior a través de la estimulación del canal semicircular posterior, que no aporta la PCC.


Introduction: The classic Fitzgerald-Hallpike caloric test (CCT) is usually utilized for evaluation of vestibular pathology. With this test, however, superior vestibular nerve function is assessed through stimulation of the lateral semicircular canal only. The minimal caloric test (MCT) allows for evaluation of both superior and inferior vestibular nerve function, through horizontal and posterior semicircular canals stimulation, respectively. The actual impact of MCT on the clinical evaluation of patients presenting with vestibular symptoms is unknown. Purpose: To quantify the diagnostic usefulness of MCT in patients with vestibular symptoms. Material and Method: Transversal diagnostic study. Sensitivity and specificity of MCT were obtained by comparing the lateral semicircular canal response in both MCT and the conventional caloric test. We assessed the number of cases in which the vestibular nerve function information obtained with MCT was relevant for vestibular diagnostic. Results: 44 patients were studied. The sensitivity and specificity of MCT to detect pathologic conditions via lateral semicircular canal stimulation were 93 percent (Cl 95 percent: 84 percent-100 percent and 80 percent-100 percent, respectively). In 16 percent (n =7) of the cases, MCT detected inferior vestibular nerve involvement with normal CCT Conclusions: MCT is a complementary test, which can be useful for evaluation of patients with vestibular symptoms, given its high sensitivity and specificity to detect superior vestibular nerve pathology through lateral semicircular canal stimulation. In addition, it provides information on the inferior vestibular nerve status, through posterior semicircular canal stimulation. The latter is not provided by conventional CCT.


Assuntos
Humanos , Masculino , Feminino , Adolescente , Adulto , Pessoa de Meia-Idade , Idoso de 80 Anos ou mais , Doenças Vestibulares/diagnóstico , Doenças Vestibulares/fisiopatologia , Testes Calóricos/métodos , Testes de Função Vestibular/métodos , Canais Semicirculares/fisiologia , Distribuição por Sexo , Estudos Prospectivos , Estudos Transversais , Nervo Vestibular/fisiologia , Sensibilidade e Especificidade , Vertigem/diagnóstico , Vertigem/fisiopatologia
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