Two new species of semiaquatic Anolis (Squamata: Dactyloidae) from Costa Rica.

We describe two new species of Draconura-clade semiaquatic anoles from the central Pacific versant of Costa Rica. The two new species are similar to Anolis aquaticus in external appearance and ecology but differ from this species in male dewlap coloration and scalation. Anolis robinsoni sp. nov. and A. riparius sp. nov. differ from each other mainly in male dewlap color. All three species are distinct according to diagnostic morphological traits and a phylogenetic analysis of mitochondrial DNA sequences (669 bases of COI gene). We discuss the distribution and ecology of Anolis aquaticus and the new species.

Three- and six-month efficacy and safety of phentermine in a Mexican obese population.

OBJECTIVE: Mexico has the second largest prevalence of obesity among adults worldwide, a condition especially affecting the low-income population. There is a pressing need to improve therapeutic options for weight loss. Phentermine is an old and low-cost agent given as an adjuvant therapy for obesity for a 12-week period, at an initial dose of 15 mg or 30 mg. However, there are no precise guidelines on the suitability of both the starting dose and the continuation of treatment for 6 months. The aim of this study was to evaluate the 3- and 6-month efficacy and safety of phentermine in obese Mexican patients to elucidate the aforementioned. MATERIALS AND METHODS: In this prospective, multi-center, open-label study, 932 obese adults received 15 mg or 30 mg phentermine once daily for 6 months. RESULTS: 30 mg phentermine was more effective than 15 mg phentermine in improving anthropometric variables in the 3-month follow-up, but not after completing the 6-month treatment period. Nearly 40% of 3-month non-responders reached a body weight reduction of at least 5% at 6 months. Conversely, ~ 65% and 25% of 3-month responders maintained or improved, respectively, their body weight reduction with long-term phentermine. Potential tolerance as weight regain was ~ 10% from 3 to 6 months. None of the doses increased cardiovascular risk, although mild-to-moderate adverse events were more frequent with 30 mg phentermine. CONCLUSION: 30 mg phentermine was more effective than 15 mg phentermine after 3 months, but not at 6 months of treatment. An important number of subjects could benefit following the therapy from 3 to 6 months.

Hypersensitivity and Applications of Cladding Modes of Optical Fibers Coated with Nanoscale Metal Layers.

Theoretical and experimental results are presented to show that the complex effective index of the modes of optical fibers coated with non-uniform metal coatings of gold, silver, copper, or palladium, with thicknesses between 0 and 20 nm, acquire a greatly enhanced sensitivity to various forms of perturbations. Thickness changes of less than 1 nm can be measured as well as the binding of record low concentrations of chemical and biochemical species.

A systematic review and mixed treatment comparison of monotherapy in early Parkinson's disease: implications for Latin America.

Parkinson's disease (PD) is the second most common neurodegenerative disease. There are no clinical trials comparing all available pharmacological therapies for the treatment of early PD. The objective of this review is to indirectly analyze the efficacy of antiparkinson drugs currently available in Latin America. A systematic review was performed exploring only placebo-controlled randomized trials comparing antiparkinson monotherapy (levodopa, pramipexole, rasagiline, or selegiline) in patients with PD on Hoehn and Yahr stages I through III published from January 1994 to May 2014. The primary outcome was the mean change in the Unified PD Rating Scale (UPDRS) I, II and III. A mixed treatment comparison analysis (indirect comparisons) through a random-effects model was performed. Levodopa demonstrated the highest effects in terms of UPDRS score improvement both from baseline and when compared to other treatments. Levodopa showed a 60.1% probability of granting the greatest reduction in UPDRS I, II and III.

Brote de bacteriemia por Burkholderia cepacia en una unidad de hemodiálisis de Cádiz, 2014 / An outbreak of Burkholderia cepacia bacteremia in a hemodialysis unit, Cadiz, 2014

INTRODUCCIÓN: En enero de 2014 se conoció la existencia de un posible brote de bacteriemia por Burkholderia cepacia en un centro concertado de hemodiálisis en La Línea de la Concepción (Cádiz). Se inició una investigación para determinar la causa del brote y establecer medidas de control. MÉTODOS: Se realizó un análisis descriptivo de los pacientes afectados por bacteriemia por Burkholderia cepacia desde noviembre de 2013 hasta febrero de 2014 y de las posibles características comunes entre cada uno de ellos. Se tomaron muestras de diferentes zonas y superficies buscando el origen el brote. Se realizó estudio de tipificación molecular mediante electroforesis en gel de campo pulsado (Spel PFGE) y análisis mediante MLST en centro de referencia para determinar la similitud genética de las cepas aisladas. RESULTADOS: En el periodo de estudio se aisló la bacteria en los hemocultivos de 7 pacientes, en 3 muestras de sellado (líquido endoluminal) de catéteres (2 de ellos fueron también casos) y en 4 muestras de botes de clorhexidina. Los pacientes eran coincidentes en 2 de los 6 turnos de diálisis. La edad media de los casos fue de 67 años. El 57% fueron mujeres. Se analizó la relación clonal entre casos y una muestra ambiental y resultaron ser idénticos genéticamente (clon ST653). CONCLUSIONES: Se confirmó la presencia de un brote de Burkholderia cepacia con 7 casos entre pacientes que estaban siendo hemodializados. El brote fue debido a una misma cepa con una fuente probablemente común y una transmisión secundaria de persona a persona

INTRODUCTION: In January 2014 a possible outbreak of Burkholderia cepacia bacteremia occurred in a hemodialysis center situated in La Linea de la Concepción (Cadiz). An investigation was begun to confirm the outbreak, identify the source, and implement control measures. METHODS: A descriptive analysis was performed to describe the characteristics of the patients affected with Burkholderia cepacia bacteremia from November 2013 to February 2014. Environmental samples were taken. A molecular typing study was performed using pulsed field gel electrophoresis (SpeI PFGE) and MLST analysis in order to determine the genetic similarity between the isolates. RESULTS: The bacterium was isolated from blood cultures of 7 patients during the study period. Three of the samples (2 of which were also cases) were endoluminal fluid from catheter locks, and 4 chlorhexidine bottle samples. The patients were coincident in 2 of the 6 work shifts. The mean age of the cases was 67 years of whom 57% were women. Human samples and an environmental sample was analyzed and found to be genetically identical (ST653 clone). CONCLUSIONS: The analysis confirmed the outbreak of Burkholderia cepacia, with 7 cases among the patients of the hemodialysis center. The outbreak was due to the same strain, probably a common source and secondary transmission from person to person

[An outbreak of Burkholderia cepacia bacteremia in a hemodialysis unit, Cadiz, 2014]. / Brote de bacteriemia por Burkholderia cepacia en una unidad de hemodiálisis de Cádiz, 2014.

INTRODUCTION: In January 2014 a possible outbreak of Burkholderia cepacia bacteremia occurred in a hemodialysis center situated in La Linea de la Concepción (Cadiz). An investigation was begun to confirm the outbreak, identify the source, and implement control measures. METHODS: A descriptive analysis was performed to describe the characteristics of the patients affected with Burkholderia cepacia bacteremia from November 2013 to February 2014. Environmental samples were taken. A molecular typing study was performed using pulsed field gel electrophoresis (SpeI PFGE) and MLST analysis in order to determine the genetic similarity between the isolates. RESULTS: The bacterium was isolated from blood cultures of 7 patients during the study period. Three of the samples (2 of which were also cases) were endoluminal fluid from catheter locks, and 4 chlorhexidine bottle samples. The patients were coincident in 2 of the 6 work shifts. The mean age of the cases was 67 years of whom 57% were women. Human samples and an environmental sample was analyzed and found to be genetically identical (ST653 clone). CONCLUSIONS: The analysis confirmed the outbreak of Burkholderia cepacia, with 7 cases among the patients of the hemodialysis center. The outbreak was due to the same strain, probably a common source and secondary transmission from person to person.

Fiber optic Fabry-Perot sensor for surface tension analysis.

We demonstrate a new technique for analyzing surface tension of liquids. This is done upon examining the interference signals reflected from a remnant drop pending at the cleaved end of a single mode optical fiber. The resulting interference patterns are fitted to a multimirror Fabry-Perot model yielding information of the drop size. We show that the wetting process of the fiber plays an important role in drop formation; in particular, the drop size can be correlated to the surface tension of the liquid sample. The proposed configuration may render useful for liquids analysis using small sample volume.

Tracking acquired antibiotic resistance in commensal bacteria of Galápagos land iguanas: no man, no resistance.

BACKGROUND: Antibiotic resistance, evolving and spreading among bacterial pathogens, poses a serious threat to human health. Antibiotic use for clinical, veterinary and agricultural practices provides the major selective pressure for emergence and persistence of acquired resistance determinants. However, resistance has also been found in the absence of antibiotic exposure, such as in bacteria from wildlife, raising a question about the mechanisms of emergence and persistence of resistant strains under similar conditions, and the implications for resistance control strategies. Since previous studies yielded some contrasting results, possibly due to differences in the ecological landscapes of the studied wildlife, we further investigated this issue in wildlife from a remote setting of the Galapagos archipelago. METHODOLOGY/PRINCIPAL FINDINGS: Screening for acquired antibiotic resistance was carried out in commensal enterobacteria from Conolophus pallidus, the terrestrial iguana of Isla Santa Fe, where: i) the abiotic conditions ensure to microbes good survival possibilities in the environment; ii) the animal density and their habits favour microbial circulation between individuals; and iii) there is no history of antibiotic exposure and the impact of humans and introduced animal species is minimal except for restricted areas. Results revealed that acquired antibiotic resistance traits were exceedingly rare among bacteria, occurring only as non-dominant strains from an area of minor human impact. CONCLUSIONS/SIGNIFICANCE: Where both the exposure to antibiotics and the anthropic pressure are minimal, acquired antibiotic resistance traits are not normally found in bacteria from wildlife, even if the ecological landscape is highly favourable to bacterial circulation among animals. Monitoring antibiotic resistance in wildlife from remote areas could also be a useful tool to evaluate the impact of anthropic pressure.

Progressive colonization and restricted gene flow shape island-dependent population structure in Galápagos marine iguanas (Amblyrhynchus cristatus).

BACKGROUND: Marine iguanas (Amblyrhynchus cristatus) inhabit the coastlines of large and small islands throughout the Galápagos archipelago, providing a rich system to study the spatial and temporal factors influencing the phylogeographic distribution and population structure of a species. Here, we analyze the microevolution of marine iguanas using the complete mitochondrial control region (CR) as well as 13 microsatellite loci representing more than 1200 individuals from 13 islands. RESULTS: CR data show that marine iguanas occupy three general clades: one that is widely distributed across the northern archipelago, and likely spread from east to west by way of the South Equatorial current, a second that is found mostly on the older eastern and central islands, and a third that is limited to the younger northern and western islands. Generally, the CR haplotype distribution pattern supports the colonization of the archipelago from the older, eastern islands to the younger, western islands. However, there are also signatures of recurrent, historical gene flow between islands after population establishment. Bayesian cluster analysis of microsatellite genotypes indicates the existence of twenty distinct genetic clusters generally following a one-cluster-per-island pattern. However, two well-differentiated clusters were found on the easternmost island of San Cristóbal, while nine distinct and highly intermixed clusters were found on youngest, westernmost islands of Isabela and Fernandina. High mtDNA and microsatellite genetic diversity were observed for populations on Isabela and Fernandina that may be the result of a recent population expansion and founder events from multiple sources. CONCLUSIONS: While a past genetic study based on pure FST analysis suggested that marine iguana populations display high levels of nuclear (but not mitochondrial) gene flow due to male-biased dispersal, the results of our sex-biased dispersal tests and the finding of strong genetic differentiation between islands do not support this view. Therefore, our study is a nice example of how recently developed analytical tools such as Bayesian clustering analysis and DNA sequence-based demographic analyses can overcome potential biases introduced by simply relying on FST estimates from markers with different inheritance patterns.

Temporal and spatial covariation of gender and oxidative stress in the Galápagos land iguana Conolophus subcristatus.

Abstract Physiological responses to organismal stress can have direct impacts on individual fitness. While responses to stressors mediated by glucocorticoid hormones are well studied, the regulation of the redox system via pro-oxidant and antioxidant balance as well as the natural causes of oxidative stress in nature remain poorly known, especially for reptiles. In this study, we investigate the interpopulation and intersex variation in oxidative damage and plasma antioxidant capacity in the Galápagos land iguana, Conolophus subcristatus, over a 3-yr study to evaluate what factors (e.g., season, food availability, reproductive activity) can explain levels and patterns of oxidative damage and of plasma antioxidant capacity. Our results indicate that (1) males showed lower levels of oxidative damage, higher levels of plasma antioxidant capacity, and better body condition than females and (2) significant interactions exist among patterns of oxidative damage across sexes, sampling localities, body condition, and season. These results suggest that reproductive activity and food abundance might act as determinants shaping levels and patterns of oxidative stress of land iguanas.

Morphometrics parallel genetics in a newly discovered and endangered taxon of Galápagos tortoise.

Galápagos tortoises represent the only surviving lineage of giant tortoises that exhibit two different types of shell morphology. The taxonomy of Galápagos tortoises was initially based mainly on diagnostic morphological characters of the shell, but has been clarified by molecular studies indicating that most islands harbor monophyletic lineages, with the exception of Isabela and Santa Cruz. On Santa Cruz there is strong genetic differentiation between the two tortoise populations (Cerro Fatal and La Reserva) exhibiting domed shell morphology. Here we integrate nuclear microsatellite and mitochondrial data with statistical analyses of shell shape morphology to evaluate whether the genetic distinction and variability of the two domed tortoise populations is paralleled by differences in shell shape. Based on our results, morphometric analyses support the genetic distinction of the two populations and also reveal that the level of genetic variation is associated with morphological shell shape variation in both populations. The Cerro Fatal population possesses lower levels of morphological and genetic variation compared to the La Reserva population. Because the turtle shell is a complex heritable trait, our results suggest that, for the Cerro Fatal population, non-neutral loci have probably experienced a parallel decrease in variability as that observed for the genetic data.

An overlooked pink species of land iguana in the Galapagos.

Despite the attention given to them, the Galápagos have not yet finished offering evolutionary novelties. When Darwin visited the Galápagos, he observed both marine (Amblyrhynchus) and land (Conolophus) iguanas but did not encounter a rare pink black-striped land iguana (herein referred to as "rosada," meaning "pink" in Spanish), which, surprisingly, remained unseen until 1986. Here, we show that substantial genetic isolation exists between the rosada and syntopic yellow forms and that the rosada is basal to extant taxonomically recognized Galápagos land iguanas. The rosada, whose present distribution is a conundrum, is a relict lineage whose origin dates back to a period when at least some of the present-day islands had not yet formed. So far, this species is the only evidence of ancient diversification along the Galápagos land iguana lineage and documents one of the oldest events of divergence ever recorded in the Galápagos. Conservation efforts are needed to prevent this form, identified by us as a good species, from extinction.

Population genetics of Galápagos land iguana (genus Conolophus) remnant populations.

The Galápagos land iguanas (genus Conolophus) have faced significant anthropogenic disturbances since the 17th century, leading to severe reduction of some populations and the extinction of others. Conservation activities, including the repatriation of captive-bred animals to depleted areas, have been ongoing since the late 1970s, but genetic information has not been extensively incorporated. Here we use nine species-specific microsatellite loci of 703 land iguanas from the six islands where the species occur today to characterize the genetic diversity within, and the levels of genetic differentiation among, current populations as well as test previous hypotheses about accidental translocations associated with early conservation efforts. Our analyses indicate that (i) five populations of iguanas represent distinct conservation units (one of them being the recently discovered rosada form) and could warrant species status, (ii) some individuals from North Seymour previously assumed to be from the natural Baltra population appear related to both Isabela and Santa Cruz populations, and (iii) the five different management units exhibit considerably different levels of intrapopulation genetic diversity, with the Plaza Sur and Santa Fe populations particularly low. Although the initial captive breeding programmes, coupled with intensive efforts to eradicate introduced species, saved several land iguana populations from extinction, our molecular results provide objective data for improving continuing in situ species survival plans and population management for this spectacular and emblematic reptile.

Genetic impact of a severe El Niño event on Galápagos marine iguanas (Amblyrhynchus cristatus).

The El Niño-Southern Oscillation (ENSO) is a major source of climatic disturbance, impacting the dynamics of ecosystems worldwide. Recent models predict that human-generated rises in green-house gas levels will cause an increase in the strength and frequency of El Niño warming events in the next several decades, highlighting the need to understand the potential biological consequences of increased ENSO activity. Studies have focused on the ecological and demographic implications of El Niño in a range of organisms, but there have been few systematic attempts to measure the impact of these processes on genetic diversity in populations. Here, we evaluate whether the 1997-1998 El Niño altered the genetic composition of Galápagos marine iguana populations from eleven islands, some of which experienced mortality rates of up to 90% as a result of El Niño warming. Specifically, we measured the temporal variation in microsatellite allele frequencies and mitochondrial DNA diversity (mtDNA) in samples collected before (1991/1993) and after (2004) the El Niño event. Based on microsatellite data, only one island (Marchena) showed signatures of a genetic bottleneck, where the harmonic mean of the effective population size (N(e)) was estimated to be less than 50 individuals during the period between samplings. Substantial decreases in mtDNA variation between time points were observed in populations from just two islands (Marchena and Genovesa). Our results suggests that, for the majority of islands, a single, intense El Niño event did not reduce marine iguana populations to the point where substantial neutral genetic diversity was lost. In the case of Marchena, simultaneous changes to both nuclear and mitochondrial DNA variation may also be the result of a volcanic eruption on the island in 1991. Therefore, studies that seek to evaluate the genetic impact of El Niño must also consider the confounding or potentially synergistic effect of other environmental and biological forces shaping populations.

Giant Galápagos tortoises; molecular genetic analyses identify a trans-island hybrid in a repatriation program of an endangered taxon.

BACKGROUND: Giant Galápagos tortoises on the island of Española have been the focus of an intensive captive breeding-repatriation programme for over 35 years that saved the taxon from extinction. However, analysis of 118 samples from released individuals indicated that the bias sex ratio and large variance in reproductive success among the 15 breeders has severely reduced the effective population size (Ne). RESULTS: We report here that an analysis of an additional 473 captive-bred tortoises released back to the island reveals an individual (E1465) that exhibits nuclear microsatellite alleles not found in any of the 15 breeders. Statistical analyses incorporating genotypes of 304 field-sampled individuals from all populations on the major islands indicate that E1465 is most probably a hybrid between an Española female tortoise and a male from the island of Pinzón, likely present on Española due to human transport. CONCLUSION: Removal of E1465 as well as its father and possible (half-)siblings is warranted to prevent further contamination within this taxon of particular conservation significance. Despite this detected single contamination, it is highly noteworthy to emphasize the success of this repatriation program conducted over nearly 40 years and involving release of over 2000 captive-bred tortoises that now reproduce in situ. The incorporation of molecular genetic analysis of the program is providing guidance that will aid in monitoring the genetic integrity of this ambitious effort to restore a unique linage of a spectacular animal.

Phylogeographic history and gene flow among giant Galápagos tortoises on southern Isabela Island.

Volcanic islands represent excellent models with which to study the effect of vicariance on colonization and dispersal, particularly when the evolution of genetic diversity mirrors the sequence of geological events that led to island formation. Phylogeographic inference, however, can be particularly challenging for recent dispersal events within islands, where the antagonistic effects of land bridge formation and vicariance can affect movements of organisms with limited dispersal ability. We investigated levels of genetic divergence and recovered signatures of dispersal events for 631 Galápagos giant tortoises across the volcanoes of Sierra Negra and Cerro Azul on the island of Isabela. These volcanoes are among the most recent formations in the Galápagos (<0.7 million years), and previous studies based on genetic and morphological data could not recover a consistent pattern of lineage sorting. We integrated nested clade analysis of mitochondrial DNA control region sequences, to infer historical patterns of colonization, and a novel Bayesian multilocus genotyping method for recovering evidence of recent migration across volcanoes using eleven microsatellite loci. These genetic studies illuminate taxonomic distinctions as well as provide guidance to possible repatriation programs aimed at countering the rapid population declines of these spectacular animals.

Inter-population variation of carotenoids in Galápagos land iguanas (Conolophus subcristatus).

Carotenoids have received much attention from biologists because of their ecological and evolutionary implications in vertebrate biology. We sampled Galápagos land iguanas (Conolophus subcristatus) to investigate the types and levels of blood carotenoids and the possible factors affecting inter-population variation. Blood samples were collected from populations from three islands within the species natural range (Santa Cruz, Isabela, and Fernandina) and one translocated population (Venecia). Lutein and zeaxanthin were the predominant carotenoids found in the serum. In addition, two metabolically modified carotenoids (anhydrolutein and 3'-dehydrolutein) were also identified. Differences in the carotenoid types were not related to sex or locality. Instead, carotenoid concentration varied across the localities, it was higher in females, and it was positively correlated to an index of body condition. Our results suggest a possible sex-related physiological role of xanthophylls in land iguanas. The variation in the overall carotenoid concentration between populations seems to be related to the differences in local abundance and type of food within and between islands.

A cryptic taxon of Galápagos tortoise in conservation peril.

As once boldly stated, 'bad taxonomy can kill', highlighting the critical importance of accurate taxonomy for the conservation of endangered taxa. The concept continues to evolve almost 15 years later largely because most legal protections aimed at preserving biological diversity are based on formal taxonomic designations. In this paper we report unrecognized genetic divisions within the giant tortoises of the Galápagos. We found three distinct lineages among populations formerly considered a single taxon on the most populous and accessible island of Santa Cruz; their diagnosability, degree of genetic divergence and phylogenetic placement merit the recognition of at least one new taxon. These results demonstrate the fundamental importance of continuing taxonomic investigations to recognize biological diversity and designate units of conservation, even within long-studied organisms such as Galápagos tortoises, whose evolutionary heritage and contribution to human intellectual history warrant them special attention.