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1.
Proc Natl Acad Sci U S A ; 120(42): e2303964120, 2023 Oct 17.
Artículo en Inglés | MEDLINE | ID: mdl-37812707

RESUMEN

We present stable hydrogen-isotope analyses of volcanic glass ([Formula: see text]Dg) and radiometric ages (U-Pb zircon, U-Th calcite, AMS14C) from deformed sedimentary deposits in the vicinity of the intermontane Pocitos Basin in the central Puna of the Andean Plateau at about 24.5°S. Our results demonstrate 2-km surface uplift since the middle to late Miocene and protracted shortening that persists until the present day, while other sectors of the Puna show evidence for tectonically neutral and/or extensional settings. These findings are at odds with previous studies suggesting near-modern elevations (4 km) of the Puna Plateau since the late Eocene and formation of the intermontane Miocene Arizaro-Pocitos Basin associated with gravitational foundering of a dense lithosphere. Geophysical and geochemical data support the removal of continental lithosphere beneath the Puna, but the timing and mechanisms by which this removal occurs have remained controversial. We hypothesize that intermontane basin formation in the central Puna is the result of crustal shortening since about 20 Ma, followed by rapid surface uplift, likely related to lithospheric delamination.

2.
Am Nat ; 203(6): 726-735, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38781524

RESUMEN

AbstractIn the world's highest mountain ranges, uncertainty about the upper elevational range limits of alpine animals represents a critical knowledge gap regarding the environmental limits of life and presents a problem for detecting range shifts in response to climate change. Here we report results of mountaineering mammal surveys in the Central Andes, which led to the discovery of multiple species of mice living at extreme elevations that far surpass previously assumed range limits for mammals. We livetrapped small mammals from ecologically diverse sites spanning >6,700 m of vertical relief, from the desert coast of northern Chile to the summits of the highest volcanoes in the Andes. We used molecular sequence data and whole-genome sequence data to confirm the identities of species that represent new elevational records and to test hypotheses regarding species limits. These discoveries contribute to a new appreciation of the environmental limits of vertebrate life.


Asunto(s)
Altitud , Animales , Ratones/genética , Ratones/fisiología , Chile , Filogenia , Distribución Animal
3.
Parasitol Res ; 121(6): 1587-1595, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35396964

RESUMEN

Free-ranging vicuñas (Vicugna vicugna) are handled in some areas of the Andean high plateau region following an ancestral practice known as chaku, which consists in their transient capture and shearing of their fiber for commercialization. In this study, 807 vicuñas captured during 12 chaku events that took place in 2019 in the province of Jujuy, Argentina, were examined for typical mange skin lesions. Twenty-eight of the examined vicuñas presented alopecia with erythema, exudation, hyperkeratosis, and/or bleeding scarred lesions, mostly in the chest, rear and front legs, and inguinal zone. Most of the cases (82%) appeared in Laguna Cucho at 4900 masl, where 23% of the animals presented these skin reactions. Microscopic evaluation of skin scrapings revealed the presence of a great number of 0.1- to 0.4-mm-long mites of different life cycle stages, morphologically compatible with the species Sarcoptes scabiei. This etiological agent was confirmed by PCR amplification and sequencing of a cox-1 species-specific segment. Histopathological examination of skin biopsies showed extensive infiltration of the dermis with lymphocytes, neutrophils and eosinophils, hyperplasia at different stages, epidermis degeneration, and hyperkeratosis. This is the first characterization of sarcoptic mange in free-ranging vicuñas by clinical examination, mite morphology, histopathological studies, and molecular confirmation in the region. Mange hampers the welfare of vicuñas and the economy of the local communities that organize chaku events since infested vicuñas cannot be sheared. Its long-term effects are unknown but it might affect the fitness and survival of this iconic South American camelid.


Asunto(s)
Camélidos del Nuevo Mundo , Escabiosis , Animales , Argentina/epidemiología , Sarcoptes scabiei/genética , Escabiosis/diagnóstico , Escabiosis/epidemiología , Escabiosis/veterinaria , Piel
4.
World J Microbiol Biotechnol ; 37(10): 166, 2021 Aug 31.
Artículo en Inglés | MEDLINE | ID: mdl-34463818

RESUMEN

Central-Andean Ecosystems (between 2000 and 6000 m above sea level (masl) are typical arid-to-semiarid environments suffering from the highest total solar and ultraviolet-B radiation on the planet but displaying numerous salt flats and shallow lakes. Andean microbial ecosystems isolated from these environments are of exceptional biodiversity enduring multiple severe conditions. Furthermore, the polyextremophilic nature of the microbes in such ecosystems indicates the potential for biotechnological applications. Within this context, the study undertaken used genome mining, physiological and microscopical characterization to reveal the multiresistant profile of Nesterenkonia sp. Act20, an actinobacterium isolated from the soil surrounding Lake Socompa, Salta, Argentina (3570 masl). Ultravioet-B, desiccation, and copper assays revealed the strain's exceptional resistance to all these conditions. Act20's genome presented coding sequences involving resistance to antibiotics, low temperatures, ultraviolet radiation, arsenic, nutrient-limiting conditions, osmotic stress, low atmospheric-oxygen pressure, heavy-metal stress, and toxic fluoride and chlorite. Act20 can also synthesize proteins and natural products such as an insecticide, bacterial cellulose, ectoine, bacterial hemoglobin, and even antibiotics like colicin V and aurachin C. We also found numerous enzymes for animal- and vegetal-biomass degradation and applications in other industrial processes. The resilience of Act20 and its biotechnologic potential were thoroughly demonstrated in this work.


Asunto(s)
Actinobacteria/genética , Actinobacteria/aislamiento & purificación , Suelo/química , Actinobacteria/química , Actinobacteria/clasificación , Argentina , Biotecnología , Ecosistema , Genoma Bacteriano , Genómica , Presión Osmótica , Microbiología del Suelo
5.
Nutr Neurosci ; 23(6): 422-431, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-30200858

RESUMEN

Objective: Maternal health and nutrition during the perinatal period is the predominant factor influencing the functional development of the brain. Maternal malnutrition during the perinatal period causes retardation of brain development. The current study investigates the role of Astaxanthin (AsX) in spatial learning and memory and BDNF in perinatally undernourished Wistar rats.Methods: The albino wistar rats were perinatally undernourished and administered with different dosages of AsX. The spatial learning and memory performance and BDNF level were assessed. Data were collected and analysed.Results: The % Correct choice during the acquisition phase, performance at the end of the acquisition phase and the mean BDNF level at the Hippocampus, Cerebellum, and Cerebral cortex showed significant decline (P<0.001) in the PUN group and significantly high (P<0.001) in the PUNA2 group compared to the control. However, the mean RME and mean WME during different days of the acquisition phase were significantly high (P<0.001) in the PUN group and insignificant (P>0.05) in PUNA2 compared to the control.Discussion: The results showed that AsX effectively modulated the cognitive deficit that occurred in perinatally undernourished rats. This can be attributed to BDNF upregulation as evidenced by the significant increase of the BDNF level.


Asunto(s)
Factor Neurotrófico Derivado del Encéfalo/metabolismo , Desnutrición/fisiopatología , Desnutrición/psicología , Aprendizaje Espacial/efectos de los fármacos , Aprendizaje Espacial/fisiología , Animales , Femenino , Fenómenos Fisiologicos Nutricionales Maternos , Embarazo , Efectos Tardíos de la Exposición Prenatal/fisiopatología , Efectos Tardíos de la Exposición Prenatal/psicología , Ratas Wistar , Xantófilas/administración & dosificación
6.
J Fish Biol ; 97(5): 1590-1594, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-32888214

RESUMEN

This is the first record of the genus Jenynsia in the High Andean Plateau (HAP). It has been found at elevations between 3400 and 3900 m in three endorreheic systems: Salar Antofalla, Antofagasta de la Sierra and El Peñón, northwestern Argentina, South America. This finding increases the number of known HAP fish genera to five. Furthermore, in contrast to the old Andean species-rich genus Orestias, the presence of Jenynsia obscura populations in young high-altitude, non-marine saline wetlands reported here supports a recent dispersal into the HAP.


Asunto(s)
Distribución Animal , Ciprinodontiformes/clasificación , Ciprinodontiformes/fisiología , Altitud , Animales , Argentina , Humedales
7.
Environ Monit Assess ; 191(10): 635, 2019 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-31522254

RESUMEN

This study aimed to analyze the spatial and temporal variation of the vegetation in the northern Argentine Puna, utilizing both field sampling and remote-sensing tools. The study was performed within the Pozuelos Biosphere Reserve (Jujuy province, Argentina), which aims to generate socio-economic development compatible with biodiversity conservation. Our study was designed to analyze the dynamics of the Puna vegetation at local scale and assess and monitor the seasonal (dry and wet seasons), interannual, and spatial variation of the vegetation cover, biomass, dominant species, and vegetation indices. Ten vegetation units (with differences in composition, cover, and high and low stratum biomass) were identified at our study site. The diversity of these vegetation units correlated with geomorphology and soil type. In the dry season, the vegetation unit with greatest vegetation cover and biomass was the Festuca chrysophylla grassland, whereas in the wet season, the units with greatest cover and biomass were vegas (peatlands) and short grasslands. The Festuca chrysophylla grasslands and short grasslands were located in areas with clay soils, except peatlands, associated with valleys and coarse-texture soils. The vegetation indices used (NDVI, SAVI, and MSAVI2) were able to differentiate functional types of vegetation and showed a good statistical fit with cover values. Our results suggest that the integrated utilization of remote-sensing tools and field surveys improves the assessment of the Puna vegetation and would allow a periodic monitoring at production unit scale taking into account its spatial and temporal variation.


Asunto(s)
Monitoreo del Ambiente/métodos , Pradera , Plantas/clasificación , Argentina , Biodiversidad , Biomasa , Parques Recreativos , Tecnología de Sensores Remotos , Estaciones del Año , Suelo/química
8.
Microb Ecol ; 76(3): 695-705, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-29520450

RESUMEN

Biofilms, microbial mats, and microbialites dwell under highly limiting conditions (high salinity, extreme aridity, pH, and elevated arsenic concentration) in the Andean Puna. Only recent pioneering studies have described the microbial diversity of different Altiplano lakes and revealed their unexpectedly diverse microbial communities. Arsenic metabolism is proposed to be an ancient mechanism to obtain energy by microorganisms. Members of Bacteria and Archaea are able to exploit arsenic as a bioenergetic substrate in either anaerobic arsenate respiration or chemolithotrophic growth on arsenite. Only six aioAB sequences coding for arsenite oxidase and three arrA sequences coding for arsenate reductase from haloarchaea were previously deposited in the NCBI database. However, no experimental data on their expression and function has been reported. Recently, our working group revealed the prevalence of haloarchaea in a red biofilm from Diamante Lake and microbial mat from Tebenquiche Lake using a metagenomics approach. Also, a surprisingly high abundance of genes used for anaerobic arsenate respiration (arr) and arsenite oxidation (aio) was detected in the Diamante's metagenome. In order to study in depth the role of arsenic in these haloarchaeal communities, in this work, we obtained 18 haloarchaea belonging to the Halorubrum genus, tolerant to arsenic. Furthermore, the identification and expression analysis of genes involved in obtaining energy from arsenic compounds (aio and arr) showed that aio and arr partial genes were detected in 11 isolates, and their expression was verified in two selected strains. Better growth of two isolates was obtained in presence of arsenic compared to control. Moreover, one of the isolates was able to oxidize As[III]. The confirmation of the oxidation of arsenic and the transcriptional expression of these genes by RT-PCR strongly support the hypothesis that the arsenic can be used in bioenergetics processes by the microorganisms flourishing in these environments.


Asunto(s)
Archaea/aislamiento & purificación , Archaea/metabolismo , Arsénico/metabolismo , Lagos/microbiología , Archaea/clasificación , Archaea/genética , Proteínas Arqueales/genética , Proteínas Arqueales/metabolismo , Arseniato Reductasas/genética , Arseniato Reductasas/metabolismo , Arseniatos/metabolismo , Biopelículas , Crecimiento Quimioautotrófico , Metabolismo Energético , Filogenia , América del Sur
9.
Glob Chang Biol ; 20(6): 1929-42, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24464954

RESUMEN

Global climate models suggest enhanced warming of the tropical mid and upper troposphere, with larger temperature rise rates at higher elevations. Changes in fire activity are amongst the most significant ecological consequences of rising temperatures and changing hydrological properties in mountainous ecosystems, and there is a global evidence of increased fire activity with elevation. Whilst fire research has become popular in the tropical lowlands, much less is known of the tropical high Andean region (>2000 masl, from Colombia to Bolivia). This study examines fire trends in the high Andes for three ecosystems, the Puna, the Paramo and the Yungas, for the period 1982-2006. We pose three questions: (i) is there an increased fire response with elevation? (ii) does the El Niño- Southern Oscillation control fire activity in this region? (iii) are the observed fire trends human driven (e.g., human practices and their effects on fuel build-up) or climate driven? We did not find evidence of increased fire activity with elevation but, instead, a quasicyclic and synchronous fire response in Ecuador, Peru and Bolivia, suggesting the influence of high-frequency climate forcing on fire responses on a subcontinental scale, in the high Andes. ENSO variability did not show a significant relation to fire activity for these three countries, partly because ENSO variability did not significantly relate to precipitation extremes, although it strongly did to temperature extremes. Whilst ENSO did not individually lead the observed regional fire trends, our results suggest a climate influence on fire activity, mainly through a sawtooth pattern of precipitation (increased rainfall before fire-peak seasons (t-1) followed by drought spells and unusual low temperatures (t0), which is particularly common where fire is carried by low fuel loads (e.g., grasslands and fine fuel). This climatic sawtooth appeared as the main driver of fire trends, above local human influences and fuel build-up cyclicity.


Asunto(s)
Cambio Climático , Clima , Ecosistema , Incendios , Altitud , Bosques , Pradera , Humanos , América del Sur , Tundra
10.
bioRxiv ; 2024 Jul 29.
Artículo en Inglés | MEDLINE | ID: mdl-39091768

RESUMEN

On the flanks of >6000 m Andean volcanoes that tower over the Atacama Desert, leaf-eared mice (Phyllotis vaccarum) live at extreme elevations that surpass known vegetation limits. What the mice eat in these barren, hyperarid environments has been the subject of much speculation. According to the arthropod fallout hypothesis, sustenance is provided by windblown insects that accumulate in snowdrifts ('aolian deposits'). It is also possible that mice feed on saxicolous lichen or forms of cryptic vegetation that have yet to be discovered at such high elevations. We tested hypotheses about the diet of mice living at extreme elevations on Atacama volcanoes by combining metagenomic and DNA metabarcoding analyses of gut contents with stable-isotope analyses of mouse tissues. Genomic analyses of contents of the gastrointestinal tract of a live-captured mouse from the 6739 m summit of Volcán Llullaillaco revealed evidence for an opportunistic but purely herbivorous diet, including lichens. Although we found no evidence of animal DNA in gut contents of the summit mouse, stable isotope data indicate that mice native to elevations at or near vegetation limits (~5100 m) include a larger fraction of animal prey in their diet than mice from lower elevations. Some plant species detected in the gut contents of the summit mouse are known to exist at lower elevations at the base of the volcano and in the surrounding Altiplano, suggesting that such plants may occur at higher elevations beneath the snowpack or in other cryptic microhabitats.

11.
Front Plant Sci ; 14: 1048609, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37180385

RESUMEN

Although wetlands contain a disproportionately high amount of earth's total soil carbon, many regions are still poorly mapped and with unquantified carbon stocks. The tropical Andes contain a high concentration of wetlands consisting mostly of wet meadows and peatlands, yet their total organic carbon stocks are poorly quantified, as well as the carbon fraction that wet meadows store compared to peatlands. Therefore, our goal was to quantify how soil carbon stocks vary between wet meadows and peatlands for a previously mapped Andean region, Huascarán National Park, Peru. Our secondary goal was to test a rapid peat sampling protocol to facilitate field sampling in remote areas. We sampled soil to calculate carbon stocks of four wetland types: cushion peat, graminoid peat, cushion wet meadow, and graminoid wet meadow. Soil sampling was conducted by using a stratified randomized sampling scheme. Wet meadows were sampled to the mineral boundary using a gouge auger, and we used a combination of full peat cores and a rapid peat sampling procedure to estimate peat carbon stocks. In the lab, soils were processed for bulk density and carbon content, and total carbon stock of each core was calculated. We sampled 63 wet meadows and 42 peatlands. On a per hectare basis, carbon stocks varied strongly between peatlands (avg. 1092 MgC ha-1) and wet meadows (avg. 30 MgC ha-1). Overall, wetlands in Huascarán National Park contain 24.4 Tg of carbon with peatlands storing 97% of the total wetland carbon and wet meadows accounting for 3% of the wetland carbon in the park. In addition, our results show that rapid peat sampling can be an effective method for sampling carbon stocks in peatlands. These data are important for countries developing land use and climate change policies as well as providing a rapid assessment method for wetland carbon stock monitoring programs.

12.
PeerJ ; 11: e14651, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36650841

RESUMEN

The biogeographic region of Argentinean Puna mainly extends at elevations higher than 3,000 m within the Andean Plateau and hosts diverse ecological communities highly adapted to extreme aridity and low temperatures. Soils of Puna are typically poorly evolved and geomorphology is shaped by drainage networks, resulting in highly vegetated endorheic basins and hypersaline basins known as salar or salt flats. Local communities rely on soil fertility for agricultural practices and on pastures for livestock rearing. From this perspective, investigating the scarcely explored microbiological diversity of these soils as indicators of ecosystems functioning might help to predict the fragility of these harsh environments. In this study we collected soil samples from 28 points, following a nested design within three different macro-habitats, i.e., Puna grassland, hypersaline salar and family-run crop fields. Total fungi and arbuscular mycorrhizal fungi (AMF) occurrence were analyzed using eDNA sequencing. In addition, the significance of soil salinity and organic matter content as significant predictors of AMF occurrence, was assessed through Generalized Linear Mixed Modeling. We also investigated whether intensive grazing by cattle and lama in Puna grasslands may reduce the presence of AMF in these highly disturbed soils, driving or not major ecological changes, but no consistent results were found, suggesting that more specific experiments and further investigations may address the question more specifically. Finally, to predict the suitability for AMF in the different macro-habitats, Species Distribution Modeling (SDM) was performed within an environmental coherent area comprising both the phytogeographic regions of Puna and Altoandino. We modeled AMF distribution with a maximum entropy approach, including bioclimatic and edaphic predictors and obtaining maps of environmental suitability for AMF within the predicted areas. To assess the impact of farming on AMF occurrence, we set a new series of models excluding the cultivated Chaupi Rodeo samples. Overall, SDM predicted a lower suitability for AMF in hypersaline salar areas, while grassland habitats and a wider temperature seasonality range appear to be factors significantly related to AMF enrichment, suggesting a main role of seasonal dynamics in shaping AMF communities. The highest abundance of AMF was observed in Vicia faba crop fields, while potato fields yielded a very low AMF occurrence. The models excluding the cultivated Chaupi Rodeo samples highlighted that if these cultivated areas had theoretically remained unmanaged habitats of Puna and Altoandino, then large-scale soil features and local bioclimatic constraints would likely support a lower suitability for AMF. Using SDM we evidenced the influence of bioclimatic, edaphic and anthropic predictors in shaping AMF occurrence and highlighted the relevance of considering human activities to accurately predict AMF distribution.


Asunto(s)
Micorrizas , Humanos , Animales , Bovinos , Micorrizas/genética , Suelo , Ecosistema , Entropía , Agricultura/métodos
13.
J Mammal ; 104(5): 1144-1151, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37800100

RESUMEN

We report an elevational record for the Andean sigmodontine Puna Mouse Punomys, which is also the first record of the genus in Chile. The record is based on a mummified specimen that we discovered at an elevation of 5,461 m (17,917 feet) in the caldera of Volcán Acamarachi, Región de Antofagasta, Chile. Results of a morphological assessment suggest that the specimen can be provisionally referred to the species P. lemminus. This new record also extends the known geographic distribution of the genus by 700 km to the south and brings the known Chilean mammal richness to a total of 170 living species and 88 genera. This finding highlights the need for increased survey efforts in more remote, high-elevation regions and demonstrates that there is still much to be learned about the mammal fauna of the Andean Altiplano.


Se reporta un registro altitudinal para el roedor sigmodontino Punomys, el cual corresponde a su vez al primer hallazgo del género para Chile. Este se basa en un espécimen momificado encontrado a una elevación de 5,461 m en la caldera del Volcán Acamarachi, Región de Antofagasta, Chile. Los caracteres morfológicos sugieren que el espécimen puede ser referido provisionalmente a la especie P. lemminus. Este nuevo registro amplía la distribución geográfica conocida del género en 700 km al sur, y eleva la riqueza de mamíferos vivientes chilenos a un nuevo total de 170 especies y 88 géneros. Este hallazgo resalta la necesidad de aumentar los esfuerzos de prospección en las regiones más remotas y de mayor altitud y demuestra que aún queda mucho por aprender sobre el ensamble de los mamíferos del Altiplano andino.

14.
Pastoralism ; 12(1): 46, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36467430

RESUMEN

Vicuñas (Vicugna vicugna) were at risk of extinction due to indiscriminate hunting for their fibre in the mid-twentieth century. The conservation of the species included numerous international and regional legal mechanisms, as well as the will and care of local communities. The vicuña was saved, and now it is classified as "Least concern" by the IUCN Red List of Threatened Species. Sustainable harvest of vicuña fibre is achieved by way of the chaku, capture and live-shearing (an ancient practice, now informed by modern knowledge of biology). Although most communities and cooperatives sell raw fibre, prices are falling. The making of artisanal vicuña garments has been identified as an activity that potentially leads to sustainable development in the Andean Altiplano. This paper analyses a key aspect to achieve this goal, a detailed description of the production (including economic and time costs) involved in weaving a shawl. The manual work has been recognized, with an hourly rate and costs calculated. The first action before starting any intervention was a ceremony, in which the family women infused the fibre with the smoke of a local plant, k'oa (Parastrephia spp.). The rituals and traditions are an important part of livelihoods in the Andes. The steps to creating the finished garment were fibre acquisition, dehairing and cleaning the fibre, spinning, twisting, loom weaving, finishing and fringing. The techniques for spinning and weaving are an essential part of the indigenous cultural heritage; no intervention or suggestion was made in that regard. The final cost of the garment was approximately 3,300 US dollars and half of this cost was the dehairing and cleaning of the fibre.

15.
Front Microbiol ; 13: 791714, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35369494

RESUMEN

In the Central Andean region in South America, high-altitude ecosystems (3500-6000 masl) are distributed across Argentina, Chile, Bolivia, and Peru, in which poly-extremophilic microbes thrive under extreme environmental conditions. In particular, in the Puna region, total solar irradiation and UV incidence are the highest on Earth, thus, restraining the physiology of individual microorganisms and the composition of microbial communities. UV-resistance of microbial strains thriving in High-Altitude Andean Lakes was demonstrated and their mechanisms were partially characterized by genomic analysis, biochemical and physiological assays. Then, the existence of a network of physiological and molecular mechanisms triggered by ultraviolet light exposure was hypothesized and called "UV-resistome". It includes some or all of the following subsystems: (i) UV sensing and effective response regulators, (ii) UV-avoidance and shielding strategies, (iii) damage tolerance and oxidative stress response, (iv) energy management and metabolic resetting, and (v) DNA damage repair. Genes involved in the described UV-resistome were recently described in the genome of Nesterenkonia sp. Act20, an actinobacterium which showed survival to high UV-B doses as well as efficient photorepairing capability. The aim of this work was to use a proteomic approach together with photoproduct measurements to help dissecting the molecular events involved in the adaptive response of a model High-Altitude Andean Lakes (HAAL) extremophilic actinobacterium, Nesterenkonia sp. Act20, under artificial UV-B radiation. Our results demonstrate that UV-B exposure induced over-abundance of a well-defined set of proteins while recovery treatments restored the proteomic profiles present before the UV-challenge. The proteins involved in this complex molecular network were categorized within the UV-resistome subsystems: damage tolerance and oxidative stress response, energy management and metabolic resetting, and DNA damage repair.

16.
PhytoKeys ; 197: 149-164, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36760673

RESUMEN

In an earlier molecular phylogenetic study, a sample of what was originally identified as Cryptanthahispida (Boraginaceae) from Chile, grouped with species of the genus Johnstonella. This sample was subsequently shown not to be C.hispida, but an undescribed species, endemic to the dry Puna of Chile. This new species is described here as Johnstonellapunensis, along with a key to all South American species of the genus. Johnstonellapunensis resembles other members of that genus in having an ovate fruit shape, ovate nutlets and a long style that extends beyond the nutlets. It is unusual in the genus in having a non-tuberculate, dimpled to rugulose nutlet surface sculpturing. Its closest relative within the genus is likely the South American J.diplotricha.


ResumenEn un estudio filogenético molecular anterior, una muestra que originalmente se identificó como Cryptanthahispida (Boraginaceae) de Chile se agrupaba con especies del género Johnstonella. Posteriormente se demostró que esta muestra no era C.hispida sino una especie no descrita, endémica de la Puna seca de Chile. Esta nueva especie se describe aquí como Johnstonellapunensis, junto con una clave para todas las especies sudamericanas del género. Johnstonellapunensis se parece a otros miembros del género por tener un fruto de forma ovadа, clusas ovadas y un estilo largo que sobrepasa las clusas. Es inusual en el género que la clusa tenga una superficie no tuberculada, sino que rugulosa formando hoyuelos. Su pariente más cercano dentro del género es probablemente la especie sudamericana J.diplotricha.

17.
Biology (Basel) ; 11(6)2022 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-35741352

RESUMEN

The Altiplano-Puna region is a high-altitude plateau in South America characterized by extreme conditions, including the highest UV incidence on Earth. The Laguna Negra is a hypersaline lake located in the Catamarca Province, northwestern Argentina, where stromatolites and other microbialites are found, and where life is mostly restricted to microbial mats. In this study, a particular microbial mat that covers the shore of the lake was explored, to unravel its layer-by-layer vertical structure in response to the environmental stressors therein. Microbial community composition was assessed by high-throughput 16S rRNA gene sequencing and pigment content analyses, complemented with microscopy tools to characterize its spatial arrangement within the mat. The top layer of the mat has a remarkable UV-tolerance feature, characterized by the presence of Deinococcus-Thermus and deinoxanthin, which might reflect a shielding strategy to cope with high UV radiation. Chloroflexi and Deltaproteobacteria were abundant in the second and third underlying layers, respectively. The bottom layer harbors copious Halanaerobiaeota. Subspherical aggregates composed of calcite, extracellular polymeric substances, abundant diatoms, and other microorganisms were observed all along the mat as the main structural component. This detailed study provides insights into the strategies of microbial communities to thrive under high UV radiation and hypersalinity in high-altitude lakes in the Altiplano-Puna region.

18.
Neotrop Entomol ; 51(6): 840-859, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36378478

RESUMEN

A comparative analysis of high-Andean Pierina was carried out, including a total of 25 species. Based on morphological evidence, with an emphasis on venation and genitalia and molecular data, using three genetic markers, we confirm the recent subjective synonymy of the generic names Tatochila Butler, 1870, Piercolias, Staudinger, 1894, Hypsochila Ureta, 1955, Infraphulia Field, 1958, Pierphulia Field, 1958, and Theochila Field, 1958 with Phulia Herrich-Schäffer, 1867. Two new species are described, namely Phulia stoddardi Pyrcz & Cerdeña n. sp., from the Andes of Central Peru, which occurs at an unusually high altitude of close to 5000 m a.s.l. in dry puna habitat, and Phulia phantasma Lamas, Willmott & Boyer n. sp., from dry montane forests in northern Peru and southern Ecuador. An overview of high-elevation butterflies is presented, with some discussion on adaptations to this environment.


Asunto(s)
Mariposas Diurnas , Animales , Ecosistema , Ecuador , Bosques , Perú
19.
Zookeys ; 1079: 1-33, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-35068957

RESUMEN

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.

20.
J Ethnopharmacol ; 251: 112553, 2020 Apr 06.
Artículo en Inglés | MEDLINE | ID: mdl-31923539

RESUMEN

ETHNOPHARMACOLOGICAL RELEVANCE: B. boliviensis and B. tola are used in traditional medicine in the Argentine Puna to treat skin and soft tissue infections and inflammatory processes in humans and animals. AIM OF THE STUDY: To assess the potential of phytotherapeutic preparations of Baccharis species as antifungal agents against clinically relevant fungi and to determine the chemical composition of the extracts. MATERIAL AND METHODS: Phytotherapeutic preparations of B. boliviensis and B. tola collected in Argentine Puna were evaluated as an antifungal agent against clinically relevant fungi (yeast, non-dermatophytes, and dermatophytes) isolated of patients from a local Hospital, and reference strains, using macrodilution and microdilution assays. The bioactivity was supported by UHPLC-OT-MS metabolome fingerprinting. RESULTS: The results revealed that the plant preparations were active against most of evaluated fungal strains; B. boliviensis was more active than B. tola. Dermatophyte fungi strains were the most sensitive isolates. The phytotherapeutic preparation showed Minimal Inhibitory Concentration (MIC) values between 25 and 400 µg GAE/mL and Minimum Fungicidal Concentration (MFC) values between 50 and 400 µg GAE/mL. Regarding the phytochemical analysis, total phenolic and total flavonoid contents of hydroalcoholic preparation of B. boliviensis were greater than those of the B. tola extract. Both Baccharis species showed similar chromatographic patterns, fifty-two compounds were identified based on UHPLC-OT-MS including several terpenoids, flavonoids and phenolic acids that have been identified in this two endemic South American Baccharis species for the first time. Several identified compounds present antifungal properties, the presence of these compounds support the bioactivity of the Baccharis extracts. CONCLUSIONS: In this work the traditional use of both Baccharis species as an antimicrobial against commercial products resistant fungal strains was validate, principally against dermatophytes fungi such as T. rubrum, T. mentagrophytes, M. canis, and M. gypseum. These results indicate that the hydroalcoholic preparations could be used for the treatment of fungal infectious.


Asunto(s)
Antifúngicos/farmacología , Baccharis , Hongos/efectos de los fármacos , Extractos Vegetales/farmacología , Antifúngicos/química , Argentina , Flavonoides/análisis , Flavonoides/farmacología , Pruebas de Sensibilidad Microbiana , Fenoles/análisis , Fenoles/farmacología , Fitoquímicos/análisis , Fitoquímicos/farmacología , Extractos Vegetales/química
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