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1.
Mycologia ; 114(4): 798-811, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35695815

RESUMO

A new species of the genus Diachea (order Physarales, Myxomycetes, Amoebozoa) is described from Peru. Relevant details on spore germination, as well as morphological and phylogenetic data, are provided. At first glance, the new species shares some morphological similarities with both D. leucopodia, type of the genus, and D. koazei, but it strikingly differs from all other species of its genus by combining a short dark stalk, with a reticulate columella, and clustered spores. Moreover, it seems to be the only species of Diachea exclusively associated with Polylepis tropical forests at elevations above 3500 m. Apart from a comprehensive morphological study of 31 specimens, we here provide phylogenetic evidence to confirm the inclusion of this species in the genus Diachea. Specifically, our phylogenetic analyses of the nuclear 18S rDNA (18S), mitochondrial 17S rDNA (17S), and elongation factor-1 alpha (EF-1α) genes show that the new species is related to D. leucopodia and D. bulbillosa. The remarkably different morphological characters distinguishing the new Diachea from all other species of its genus, along with its particular ecological preferences and geographic distribution, indicate that it is a distinct entity deserving recognition as an independent species.


Assuntos
Mixomicetos , DNA Ribossômico/genética , Florestas , Mixomicetos/genética , Peru , Filogenia
2.
Clin Toxicol (Phila) ; 59(10): 860-868, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34219550

RESUMO

CONTEXT: The black mamba (Dendroaspis polylepis) is, due to its extremely toxic venom, one of the most dangerous snake species in Sub-Saharan Africa. A D. polylepis bite is a medical emergency and requires adequate action to prevent severe complications. However, there are no comprehensive reviews available based on clinical cases, and no readily accessible guidelines for standardized treatment. Therefore, we aim to provide an overview regarding the currently available clinical literature on D. polylepis envenomations; in order to promote knowledge on symptomatology and treatment options. METHODS: We searched for cases reporting humans bitten by D. polylepis in PubMed, Embase, Scopus, and Sabinet. We searched the reference lists of all eligible articles for additional articles. After quality assessment, 29 cases were included in this review. We used descriptive analysis to create an overview of the collected parameters. DISCUSSION: Among the included case reports and case series, D. polylepis envenomations most frequently resulted in decreased respiratory function, sweating and paralysis. The onset of symptoms usually occurred within 60 minutes. Neurological symptoms occurred more often than symptoms of autonomic dysfunction. In the reported cases most patients (26/29) received antivenom and most survived (25/29). We recommend the reporting of additional structured case reports to improve future analyses on the clinical course of envenomations, in order to improve public health response to D. polylepis envenomations.


Assuntos
Antivenenos/uso terapêutico , Dendroaspis , Venenos Elapídicos/antagonistas & inibidores , Mordeduras de Serpentes/tratamento farmacológico , Adolescente , Adulto , Animais , Criança , Pré-Escolar , Dendroaspis/metabolismo , Venenos Elapídicos/metabolismo , Feminino , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Mordeduras de Serpentes/diagnóstico , Mordeduras de Serpentes/metabolismo , Mordeduras de Serpentes/mortalidade , Resultado do Tratamento , Adulto Jovem
3.
J Parasitol ; 107(1): 1-15, 2021 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-33429430

RESUMO

The lecanicephalidean cestodes parasitizing the spiral intestine of the endangered giant freshwater whipray, Urogymnus polylepis (Bleeker), are investigated for the first time. Eight host specimens were collected between 2002 and 2008 at 2 collecting sites off the eastern coast of Borneo: 6 from the Kinabatangan River (Malaysia) and 2 from a fish market in Tarakan (Indonesia). Two of these individuals were found to be infected with a total of 3 new species of TetragonocephalumShipley and Hornell, 1905. Tetragonocephalum georgei n. sp. and Tetragonocephalum opimum n. sp. were recovered from a host specimen from the Kinabatangan River, and Tetragonocephalum levicorpum n. sp. was found parasitizing a host specimen purchased at a fish market in Tarakan. Specimens of each of the new species were prepared for light microscopy; specimens of 2 of the new species were prepared for scanning electron microscopy, and histological sections were prepared for 1 of the new species. The 3 new species are distinct from the 9 valid species of Tetragonocephalum and the 1 species inquirendum based on, for example, total length, number of proglottids and testes, and size of the scolex and acetabula. Tetragonocephalum georgei n. sp. and T. levicorpum n. sp. are unusual among their congeners in that they are euapolytic (i.e., gravid proglottids were not observed) rather than apolytic. They differ from one another in scolex and acetabula size. Tetragonocephalum opimum n. sp. is unusual among its congeners in its possession of vitelline follicles arranged in 2, rather than 3, regions in the proglottid. These new species increase the total number of valid species of Tetragonocephalum to 12 and the total number of known cestodes from U. polylepis to 13 species across 6 genera in 4 orders. This is the first account of lecanicephalideans reported from freshwater. The taxonomic status of each of the 32 nominal taxa historically associated with Tetragonocephalum is re-assessed. Type host identities of all valid species are revised and discussed in light of recent taxonomic efforts in the Dasyatidae Jordan and Gilbert.


Assuntos
Cestoides/isolamento & purificação , Infecções por Cestoides/veterinária , Doenças dos Peixes/parasitologia , Água Doce/parasitologia , Rajidae/parasitologia , Animais , Bornéu/epidemiologia , Cestoides/classificação , Cestoides/ultraestrutura , Infecções por Cestoides/epidemiologia , Infecções por Cestoides/parasitologia , Feminino , Doenças dos Peixes/epidemiologia , Indonésia/epidemiologia , Intestinos/parasitologia , Malásia/epidemiologia , Masculino , Microscopia Eletrônica de Varredura , Rios/parasitologia
4.
Artigo em Inglês | MEDLINE | ID: mdl-33088285

RESUMO

BACKGROUND: Proteases play an important role for the proper physiological functions of the most diverse organisms. When unregulated, they are associated with several pathologies. Therefore, proteases have become potential therapeutic targets regarding the search for inhibitors. Snake venoms are complex mixtures of molecules that can feature a variety of functions, including peptidase inhibition. Considering this, the present study reports the purification and characterization of a Kunitz-type peptide present in the Dendroaspis polylepis venom as a simultaneous inhibitor of elastase-1 and cathepsin L. METHODS: The low molecular weight pool from D. polylepis venom was fractionated in reverse phase HPLC and all peaks were tested in fluorimetric assays. The selected fraction that presented inhibitory activity over both proteases was submitted to mass spectrometry analysis, and the obtained sequence was determined as a Kunitz-type serine protease inhibitor homolog dendrotoxin I. The molecular docking of the Kunitz peptide on the elastase was carried out in the program Z-DOCK, and the program RosettaDock was used to add hydrogens to the models, which were re-ranked using ZRANK program. RESULTS: The fraction containing the Kunitz molecule presented similar inhibition of both elastase-1 and cathepsin L. This Kunitz-type peptide was characterized as an uncompetitive inhibitor for elastase-1, presenting an inhibition constant (Ki) of 8 µM. The docking analysis led us to synthesize two peptides: PEP1, which was substrate for both elastase-1 and cathepsin L, and PEP2, a 30-mer cyclic peptide, which showed to be a cathepsin L competitive inhibitor, with a Ki of 1.96 µM, and an elastase-1 substrate. CONCLUSION: This work describes a Kunitz-type peptide toxin presenting inhibitory potential over serine and cysteine proteases, and this could contribute to further understand the envenomation process by D. polylepis. In addition, the PEP2 inhibits the cathepsin L activity with a low inhibition constant.

5.
Rev. peru. biol. (Impr.) ; 27(3): 273-282, jul-sep 2020. tab, graf
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1144961

RESUMO

Resumen Se describe, diagnostica e ilustra una nueva especie de Bistriopelma Kaderka 2015, Bistriopelma fabianae sp. nov., para la región de Arequipa en el sur de Perú. Los especímenes se encontraron en un bosque de Queñua (Polylepis rugulosa Bitter) ubicado en las faldas del volcán Pichu Pichu en la zona de amortiguamiento de la Reserva Nacional de Salinas y Aguada Blanca. Se presentan datos biológicos y ecológicos de B. fabianae sp. nov. y también notas adicionales sobre B. kiwicha y B. peyoi, dos nuevas especies recientemente descritas de las regiones de Apurímac y Cusco.


Abstract A new species of Bistriopelma Kaderka 2015, Bistriopelma fabianae sp. nov., from the Arequipa region in southern Peru is described, diagnosed, and illustrated. Specimens were found in a Queñua forest (Polylepis rugulosa Bitter) spread out on the slopes of Pichu Pichu volcano in the buffer zone of Salinas and Aguada Blanca National Reserve. Biological and ecological data of B. fabianae sp. nov. are provided as well as notes on B. kiwicha and B. peyoi, two new species recently described from Apurimac and Cusco regions.

6.
J Venom Anim Toxins Trop Dis, v. 26, e20200037, out. 2020
Artigo em Inglês | Sec. Est. Saúde SP, SESSP-IBPROD, Sec. Est. Saúde SP | ID: bud-3286

RESUMO

Background: Proteases play an important role for the proper physiological functions of the most diverse organisms. When unregulated, they are associated with several pathologies. Therefore, proteases have become potential therapeutic targets regarding the search for inhibitors. Snake venoms are complex mixtures of molecules that can feature a variety of functions, including peptidase inhibition. Considering this, the present study reports the purification and characterization of a Kunitz-type peptide present in the Dendroaspis polylepis venom as a simultaneous inhibitor of elastase-1 and cathepsin L. Methods: The low molecular weight pool from D. polylepis venom was fractionated in reverse phase HPLC and all peaks were tested in fluorimetric assays. The selected fraction that presented inhibitory activity over both proteases was submitted to mass spectrometry analysis, and the obtained sequence was determined as a Kunitz-type serine protease inhibitor homolog dendrotoxin I. The molecular docking of the Kunitz peptide on the elastase was carried out in the program Z-DOCK, and the program RosettaDock was used to add hydrogens to the models, which were re-ranked using ZRANK program. Results: The fraction containing the Kunitz molecule presented similar inhibition of both elastase-1 and cathepsin L. This Kunitz-type peptide was characterized as an uncompetitive inhibitor for elastase-1, presenting an inhibition constant (Ki) of 8 μM. The docking analysis led us to synthesize two peptides: PEP1, which was substrate for both elastase-1 and cathepsin L, and PEP2, a 30-mer cyclic peptide, which showed to be a cathepsin L competitive inhibitor, with a Ki of 1.96 µM, and an elastase-1 substrate. Conclusion: This work describes a Kunitz-type peptide toxin presenting inhibitory potential over serine and cysteine proteases, and this could contribute to further understand the envenomation process by D. polylepis. In addition, the PEP2 inhibits the cathepsin L activity with a low inhibition constant.

7.
J. venom. anim. toxins incl. trop. dis ; 26: e20200037, 2020. graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1135157

RESUMO

Proteases play an important role for the proper physiological functions of the most diverse organisms. When unregulated, they are associated with several pathologies. Therefore, proteases have become potential therapeutic targets regarding the search for inhibitors. Snake venoms are complex mixtures of molecules that can feature a variety of functions, including peptidase inhibition. Considering this, the present study reports the purification and characterization of a Kunitz-type peptide present in the Dendroaspis polylepis venom as a simultaneous inhibitor of elastase-1 and cathepsin L. Methods: The low molecular weight pool from D. polylepis venom was fractionated in reverse phase HPLC and all peaks were tested in fluorimetric assays. The selected fraction that presented inhibitory activity over both proteases was submitted to mass spectrometry analysis, and the obtained sequence was determined as a Kunitz-type serine protease inhibitor homolog dendrotoxin I. The molecular docking of the Kunitz peptide on the elastase was carried out in the program Z-DOCK, and the program RosettaDock was used to add hydrogens to the models, which were re-ranked using ZRANK program. Results: The fraction containing the Kunitz molecule presented similar inhibition of both elastase-1 and cathepsin L. This Kunitz-type peptide was characterized as an uncompetitive inhibitor for elastase-1, presenting an inhibition constant (Ki) of 8 μM. The docking analysis led us to synthesize two peptides: PEP1, which was substrate for both elastase-1 and cathepsin L, and PEP2, a 30-mer cyclic peptide, which showed to be a cathepsin L competitive inhibitor, with a Ki of 1.96 µM, and an elastase-1 substrate. Conclusion: This work describes a Kunitz-type peptide toxin presenting inhibitory potential over serine and cysteine proteases, and this could contribute to further understand the envenomation process by D. polylepis. In addition, the PEP2 inhibits the cathepsin L activity with a low inhibition constant.(AU)


Assuntos
Animais , Peptídeos , Serina , Venenos de Serpentes , Cisteína Proteases , Elapidae , Peptídeo Hidrolases/isolamento & purificação , Espectrometria de Massas
8.
Appl Plant Sci ; 7(6): e11270, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31236317

RESUMO

PREMISE: Nuclear microsatellite markers were developed for Saussurea polylepis (Asteraceae), a vulnerable species with very limited distribution in a few southwestern continental islands of the Korean peninsula, in order to facilitate future population genetic studies. METHODS AND RESULTS: Based on the Illumina sequence data, a total of 21 microsatellite primer pairs were designed and tested for their suitability. Nineteen of these primers, with two to 11 alleles per locus, were polymorphic in three natural populations of S. polylepis. The levels of expected and observed heterozygosity ranged from 0.000 to 0.842 and 0.000 to 0.933, respectively. Sixteen of these simple sequence repeat (SSR) markers were successfully cross-amplified in five congeneric species, namely S. gracilis, S. grandifolia, and S. tanakae for all 21 loci, and S. maximowiczii and S. pulchella for 18 loci. CONCLUSIONS: The SSR markers developed here will be useful for future population genetic studies on S. polylepis and related species.

9.
Rev. peru. biol. (Impr.) ; 26(2): 259-264, abr.-jun. 2019. ilus, tab
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1094377

RESUMO

La cotinga cariblanca Zaratornis stresemanni (Koepcke, 1954) (Aves: Cotingidae) es un ave endémica del Perú especialista de bosques de Polylepis. Actualmente se encuentra amenazada por la pérdida y degradación de su hábitat. En esta nota reportamos dos registros documentados al noroeste del departamento de Arequipa, en el sur de Perú, los cuales amplían en al menos 130 km su rango de distribución austral y corresponden a los primeros registros documentados de la especie para el departamento de Arequipa. Se sugiere que la cotinga cariblanca residiría en los bosques de Polylepis en el noroeste de Arequipa.


The White-cheeked Cotinga Zaratornis stresemanni (Koepcke, 1954) (Birds: Cotingidae) is an endemic bird of Peru, specialist of Polylepis forests. Is currently threatened by habitat loss and degradation. In this note, we document records to the northwest of Arequipa department, in southern Peru. These records extend in at least 130 km the austral distribution range and correspond to the first documented records of the species for Arequipa department. We suggest that the White-cheeked Cotinga would be resident in the Polylepis forests in northwest Arequipa.

10.
Zootaxa ; 4544(4): 589-597, 2019 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-30647261

RESUMO

Pseudoamycle polylepisae gen. et sp. nov. is described from northernmost Chile (Arica and Parinacota Region). It is characterized by the small and brown body, head with no preocular flange, cephalic process porrect and dorsoventrally compressed, dorsal surface from lateral view not angulate at level of eyes, eyes round, tegmina concolorous and vein MP of tegmen pectinate. The new taxon was found to be associated with Polyepis rugulosa Bitter (Rosaceae).


Assuntos
Hemípteros , Rosaceae , Animais , Chile , Olho , Cabeça
11.
Trop Med Infect Dis ; 3(3)2018 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-30274500

RESUMO

The black mamba (Dendroaspis polylepis) ranks consistently as one of the most revered snakes in sub-Saharan Africa. It has potent neurotoxic venom, and envenomation results in rapid onset and severe clinical manifestations. This report describes the clinical course and reversal of effects of black mamba envenomation in a 13-year-old boy in the Jimba area of Malindi. The victim presented to Watamu Hospital, a low resource health facility with labored breathing, frothing at the mouth, severe ptosis and pupils non-responsive to light. His blood pressure was unrecordable, heart rate was 100 beats per minute but thready, his temperature was 35.5 °C, and oxygen saturation was 83%. Management involved suction to clear salivary secretions, several hours of mechanical ventilation via ambu-bagging, oxygen saturation monitoring, and the use of South African Vaccine Producers (SAVP) polyvalent antivenom. Subcutaneous adrenaline was used to stave off anaphylaxis. The victim went into cardiac arrest on two occasions and chest compressions lasting 3⁻5 min was used to complement artificial ventilation. Hemodynamic instability was corrected using IV infusion of ringers lactate and normal saline (three liters over 24 h). Adequate mechanical ventilation and the use of specific antivenom remain key in the management of black mamba envenomation.

12.
Mitochondrial DNA B Resour ; 3(2): 1117-1119, 2018 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-33474438

RESUMO

The environmental changes mainly caused by water pollution and human activities have dramatically threatened the survival of the small-scaled Wu's goby W. polylepis. In the present study, the complete mitogenome of Wuhaniligobius polylepis was determined, which is 16,496 bp in length, containing 13 PCGs, two rRNA genes, 22 tRNA genes and a putative control region. The overall base composition is 28.6%, 29.0%, 26.7%, and 15.7% for A, T, C and G, respectively. The 13 PCGs encode 3,802 amino acids in total, twelve of which use the initiation codon ATG except COI, which uses GTG. In order to explore the systematic status of W. polylepis and further phylogenetic study of Gobiiformes, a maximum-likelihood tree was constructed based on the concatenated sequences of 12 PCGs. The result showed that Pseudogobius, Hemigobius, and Mugilogobius clustered into a clade and then formed a sister-group with W. polylepis, suggesting the invalid former name of M. polylepis or E. polylepis.

13.
Toxicon ; 138: 151-158, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28867663

RESUMO

Polyvalent snakebite antivenoms derive their therapeutic success from the ability of their antibodies to neutralize venom toxins across multiple snake species. This ability results from a production process involving immunization of large mammals with a broad suite of toxins present in venoms. As a result of immunization with this wide range of toxins, many polyvalent antivenoms have a high degree of cross-reactivity to similar toxins in other snake venoms - a cross-reactivity which cannot easily be deconvoluted. As a proof of concept, we aimed at exploring the opposite scenario by performing a high-throughput evaluation of the extent of cross-reactivity of a polyclonal mixture of antibodies that was raised against only a single snake venom fraction. For this purpose, a venom fraction containing short neurotoxin 1 (SN-1; Uniprot accession number P01416, three-finger toxin (3FTx) family), which is the medically most important toxin from the notorious black mamba (Dendroaspis polylepis), was employed. Following immunization of a rabbit, a specific polyclonal antibody response was confirmed by ELISA and immunodiffusion. Subsequently, these antibodies were investigated by high-density peptide microarray to reveal linear elements of recognized epitopes across 742 3FTxs and 10 dendrotoxins. This exploratory study demonstrates in a single immunized animal that cross-reactivity between toxins of high similarity may be difficult to obtain when immunizing with a single 3FTx containing venom fraction. Additionally, this study explored the influence of employing different lengths of peptides in high-density peptide microarray experiments for identification of toxin epitopes. Using 8-mer, 12-mer, and 15-mer peptides, a single linear epitope element was identified in SN-1 with high precision.


Assuntos
Formação de Anticorpos/imunologia , Reações Cruzadas , Dendroaspis , Venenos Elapídicos/imunologia , Animais , Imunização , Peptídeos/imunologia , Análise Serial de Proteínas , Coelhos
14.
PeerJ ; 5: e3220, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28462030

RESUMO

BACKGROUND: As one of the highest forest ecosystems in the world, Polylepis forests are recognized both as center of endemism and diversity along the Andes and as an ecosystem under serious threat from habitat loss, fragmentation, and climate change due to human activities. Effective conservation efforts are limited, in part, by our poor understanding of the ecology and habitat needs of the ecosystem's flora and fauna. METHODS: In 2014-2015, we studied bird communities and 19 associated local and landscape attributes within five forested glacial valleys within the Cordillera Blanca and Huascaran National Park, Peru. We surveyed birds during the dry (May-August) and wet (January-April) seasons at 130 points distributed along an elevational gradient (3,300-4,700 m) and analyzed our data using Canonical Correspondence Analysis (CCA). RESULTS: We associated a total of 50 species of birds, including 13 species of high conservation concern, with four basic habitat types: (1) Polylepis sericea forests at low elevations, (2) P. weberbaueri forests at high elevations, (3) Puna grassland and (4) shrublands. Four species of conservation priority (e.g., Microspingus alticola) were strongly associated with large forest patches (∼10-ha) of P. sericea at lower elevations (<3,800 m), whereas another four (e.g., Anairetes alpinus) were associated with less disturbed forests of P. weberbaueri at higher elevations (>4,200 m). DISCUSSION: Results suggest two key strategies form the cornerstones of conservation efforts: (a) protect large remnant (>10-ha) P. sericea forests at lower elevations and (b) maintain all relicts of P. weberbaueri, irrespective of size, at high elevations (>4,200 m).

15.
Mitochondrial DNA B Resour ; 2(2): 650-651, 2017 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-33473934

RESUMO

The complete chloroplast genome sequence of Saussurea polylepis, one of vulnerable and endemic species of Korea, was determined. The genome size was 152,488 bp in length with 37.7% GC content. It included a pair of inverted repeats (IRa and IRb) of 25,191 bp, which were separated by small single copy (SSC: 18,689 bp) and large single copy (LSC: 83,417 bp) regions. The cp genome contained 113 genes, including 80 protein-coding genes, 29 tRNA genes, and four rRNA genes. Phylogenetic analysis of the combined 80 protein coding genes and four rRNA genes showed that S. polylepis was closely related to S. chabyoungsanica.

16.
Plant Biol (Stuttg) ; 19(2): 123-131, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27714909

RESUMO

Steep climatic gradients boost morphological and physiological adjustments in plants, with consequences on performance. The three principal woody species of the Sierras Grandes Mountains of central Argentina have marked differences in sapling performance along their altitudinal distribution. We hypothesize that the steep gradient of climatic conditions across the species' altitudinal distribution promotes trait differences between populations of different altitudes that are inherited by the following generation. Seeds from different altitudes were exposed to three temperature regimes to assess differential germination responses. Saplings were then transplanted to a greenhouse to assess possible variations in attributes and performance after 18 months. The three species showed differences in germination responses to temperature among altitudes and/or in sapling attributes and performance. In Maytenus boaria and Escallonia cordobensis, germination success was higher under high temperatures for the highest-altitude, whereas lower temperatures boosted germination of the lowest altitudes. Polylepis australis showed no differences in germination among temperature treatments. In the greenhouse, saplings of the three species from intermediate altitudes showed high performance, whereas the upper and lower populations seemed to be adjusted to tolerating more stressful conditions (i.e., lower temperatures at the upper end and water stress at the lower end), showing lower performance toward both altitudinal limits. These patterns agree with those described for saplings growing under field conditions, suggesting adjustments in response to environmental changes undergone by populations along the altitudinal range. The marked adjustments of populations to the local environment suggest a potentially high impact of climatic change on species distribution.


Assuntos
Aclimatação , Altitude , Germinação/fisiologia , Magnoliopsida/fisiologia , Argentina , Biomassa , Mudança Climática , Temperatura Baixa , Magnoliopsida/crescimento & desenvolvimento , Fenótipo , Sementes/crescimento & desenvolvimento , Sementes/fisiologia , Árvores
17.
Rev. biol. trop ; 64(4): 1683-1697, oct.-dic. 2016. tab, ilus
Artigo em Espanhol | LILACS | ID: biblio-958243

RESUMO

Resumen:La fragmentación de los ecosistemas es uno de los fenómenos antrópicos de mayor impacto global, y el efecto borde provoca que solo el interior de los fragmentos conserve sus características bióticas y abióticas originales. Los líquenes son organismos especialmente susceptibles a la variabilidad ambiental, lo que podría ser útil para la bio-indicación del efecto borde. En este trabajo se evaluó el efecto borde en dos fragmentos de Polylepis quadrijuga en el Páramo de la Rusia (Boyacá-Colombia), para determinar si existe un efecto borde sobre la distribución de los líquenes asociados a P. quadrijuga y su contenido de clorofilas. Se utilizaron tres transectos de 70 m a través del gradiente matriz-borde-interior en cada fragmento. Se escogieron nueve forofitos por transecto para medir variables ambientales: radiación fotosintéticamente activa, humedad relativa y temperatura del aire, y variables biológicas: riqueza y cobertura de cada especie. Además, fueron elegidas las especies que estaban presentes en las tres zonas del gradiente para cuantificar el contenido de clorofilas a y b, y determinar si hay cambios en la relación de clorofilas a/b que podrían sugerir plasticidad fisiológica como respuesta al efecto borde. Nuestros resultados mostraron que el fragmento 2 tenía una mayor exposición al borde debido a su alta relación perímetro/área, lo que causa una homogenización ambiental y pérdida de biodiversidad con relación con el fragmento 1. En general, se encontraron 55 especies que se distribuyen diferencialmente en relación con los fragmentos y el gradiente matriz-borde-interior. El interior del fragmento 1 fue la zona más conservada, que alberga una composición diferente en más de un 40 % a la composición de cualquier otra zona. Se clasificaron los líquenes de acuerdo con sus hábitos: gelatinosos, fruticosos, costrosos o foliosos, pero no se encontró ninguna relación entre la distribución por hábito y el efecto borde. Seis especies de amplia distribución mostraron cambios en el contenido de clorofila a lo largo del gradiente matriz-borde-interior, lo que es una evidencia de la plasticidad fisiológica al efecto borde. También fue posible diferenciar entre especies con preferencia por ambientes de alta temperatura y especies con preferencia a lugares más húmedos y suficientemente irradiados. Se concluye que algunas especies podrían tener un importante potencial como bio-indicadores de la fragmentación en ambientes de páramo.


Abstract:The ecosystems fragmentation is one of the anthropic phenomena with highest impact at global level and the edge effect causes that only the interior of fragments conserves their original biotic and abiotic characteristics. Lichens are organisms especially susceptible to environmental variability, what could be useful for bio-indication of edge effect. In this work, we evaluated the edge effect in two fragments of Polylepis quadrijuga in the Páramo de la Rusia (Boyacá-Colombia) to determine if there is an edge effect on distribution of lichens associated to P. quadrijuga and their chlorophyll content. We used three transects of 70 m across the matrix-edge-interior gradient in each fragment. We chose nine phorophytes per transect to measure the environmental variables: photosynthetically active radiation, relative humidity and air temperature, and the biological variables: richness and cover per species. Besides, we employed the species that were present in all the three zones of the gradient to quantify the content of chlorophylls a and b, and determine if there are changes in the ratio of chlorophylls a/b that could suggest physiological plasticity as a response to the edge effect. Our results showed that fragment 2 had a higher edge exposition because of its high relation perimeter/area, allowing to an environmental homogenization and lose of biodiversity in relation with fragment 1. Overall, we found 55 differentially distributed species in relation with the fragments and the matrix-edge-interior gradient. The interior of fragment 1 was the most conserved zone, harboring a composition different in more than 40 % to the composition of any other zone. We classified the lichens according with their habits: gelatinous, fruticose, crusty or foliose, but we did not find any relationship between the habit distribution and the edge effect. Six species of wide distribution showed changes in the chlorophyll content along the matrix- edge-interior gradient, what is an evidence of physiological plasticity to edge effect. It was also possible to distinguish between species with preference to warmer environment and species with preference to more humid and sufficiently irradiated places. We concluded that some species of lichens could have an important potential as bio-indicators of fragmentation in the páramo. Rev. Biol. Trop. 64 (4): 1683-1697. Epub 2016 December 01.


Assuntos
Clorofila/análise , Rosaceae/química , Líquens/química , Energia Solar , Especificidade da Espécie , Temperatura , Clorofila/fisiologia , Análise de Variância , Colômbia , Rosaceae/fisiologia , Biodiversidade
18.
J Ethnopharmacol ; 194: 981-986, 2016 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-27794508

RESUMO

AIM OF THE STUDY: Pleopeltis polylepis (Polypodaceae) is a fern used in the traditional Mexican medicine to treat fever, bleeding, typhoid, cough, pertussis, chest pain, and renal and hepatic diseases. The aim of this study was to analyze the bioactivities of different extracts, fractions and isolated compounds from this species to scientifically validate its medicinal applications. MATERIALS AND METHODS: Aerial parts of P. polylepis were macerated and extracted consecutively with hexane, chloroform, and methanol. These extracts were subsequently fractionated and compounds from hexane and methanol extracts were purified. The antimicrobial activity was assessed using a panel of eight Gram-positive and -negative bacterial and four fungal strains. The cytotoxicity of the compounds was assessed by flow cytometry using propidium iodide and the human-derived monocytic cell line THP-1. The anti-inflammatory activity was investigated by measuring the secretion of interleukin-6 and IL-10 using also the cell line THP-1. RESULTS: Various extracts, fractions and compounds obtained from this plant showed antibacterial activity against both Gram-positive and -negative strains. Antifungal activity was confirmed only in Candida albicans and Tricophyton mentagrophytes. Two fractions and two isolated compounds (butyl myristate and ß-sitosterol) showed no significant cytotoxicity and were further evaluated for their anti-inflammatory activity. All four samples tested showed an anti-inflammatory activity similar to prednisone used as a control. CONCLUSIONS: The benefit of P. polylepis as a traditional plant related to its antimicrobial and anti-inflammatory activities was confirmed by in vitro assays. To the best of our knowledge, this is the first study reporting the isolation and bioactivities of extracts, fractions or isolated compounds from P. polylepis.


Assuntos
Anti-Infecciosos/farmacologia , Anti-Inflamatórios/farmacologia , Citotoxinas/farmacologia , Extratos Vegetais/farmacologia , Polypodiaceae/química , Anti-Infecciosos/química , Anti-Inflamatórios/química , Linhagem Celular , Citotoxinas/química , Fungos/efeitos dos fármacos , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Humanos , Interleucina-10/metabolismo , Interleucina-6/metabolismo , Medicina Tradicional , México , Ácido Mirístico/química , Ácido Mirístico/farmacologia , Extratos Vegetais/química , Sitosteroides/química , Sitosteroides/farmacologia
19.
Rev. peru. biol. (Impr.) ; 23(3): 271-286, Sept.-Dec. 2016. ilus, tab
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1094269

RESUMO

Los bosques de Polylepis (Rosaceae) forman parte de la vegetación natural de los Andes entre los 3500 y 5000 msnm, con una distribución comúnmente restringida a laderas rocosas y quebradas, constituyéndose como ecosistemas de gran importancia. Durante los años 2008-2010 se realizaron recolectas de muestras botánicas dentro de los bosques Yauyinazo y Chaqsii-Chaqsii de la Reserva Paisajística Nor Yauyos-Cochas, en dos épocas del año (húmeda y seca). Se da a conocer la composición de la flora vascular y la variación temporal en los bosques en estudio. Se registró un total de 282 especies agrupadas en 170 géneros y 62 familias, donde las Asteraceae y Poaceae fueron las familias más diversas. Con respecto a la forma de crecimiento las plantas herbáceas y arbustivas fueron las más frecuentes con 71.6% y 17.4% respectivamente. En el bosque Yauyinazo se registraron 232 especies agrupadas en 153 géneros y 58 familias y en el bosque Chaqsii-Chaqsii 213 especies en 137 géneros y 56 familias. Se registraron 41 especies endémicas y 17 especies de flora silvestre amenazada, evidenciándose la importancia ecológica de los bosques de Polylepis.


Polylepis (Rosaceae) forests are part of the natural vegetation of the Andes between 3500 and 5000 m altitude, usually restricted to rocky slopes and ravines and becoming important ecosystems. During 2008-2010 were made specimens collections in the Yauyinazo and Chaqsii-Chaqsii Polylepis forest into Reserva Paisajística Nor Yauyos-Cochas in two seasons (wet and dry). We present, the vascular flora and seasonal variation the Yauyinazo and Chaqsii-Chaqsii forests. Was registered 282 species in two forests, belonging 170 genera and 62 families, the Asteraceae and Poaceae families were the most diverse. Herbaceous and shrub plants were the most diverse with 71.6% and 17.4% respectively. In Yauyinazo forest were registered 232 species belonging 153 genera and 58 families and in the Chaqsii-Chaqsii forest 213 species belonging 137 genera and 56 families. We report 41 species endemic and 17 threatened flora species, demonstrating the importance of Polylepis forests as habitat for these species.

20.
PhytoKeys ; (65): 57-90, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27489489

RESUMO

We provide an updated checklist and key to the 30 Poa species with open panicles from Peru which includes previously circumscribed Dissanthelium and Aphanelytrum species, new taxon records, and three undescribed species. Poa compressa, Poa grisebachii, and Poa leioclada are recorded from Peru for the first time. A number of species are placed in synonymy: Poa carazensis, Poa ferreyrae and Poa tovarii are synonymized under the name Poa fibrifera; Poa adusta (tentatively) and Poa pilgeri are synonymized under Poa candamoana; Poa superata is synonymized under Poa grisebachii; and Poa paramoensis is synonymized under Poa huancavelicae. Included within this treatment are three new species, Poa ramoniana, Poa tayacajaensis and Poa urubambensis, which are described and illustrated. Poa ramoniana, found growing near lakes in high elevation Puna grasslands of Junín, is similar to a small form of Poa glaberrima, but differs in having rhizomes and growing to only 5 cm tall. Poa tayacajaensis, found from shrublands on Andean slopes of Huancavelica and Huánuco, bears similarities to Poa aequatoriensis but differs in having shorter lemmas which are pubescent between the veins, densely scabrous sheaths with smooth, glabrous throats, and shorter ligules. Poa urubambensis, a common element of the undisturbed Polylepis forest understory of the Cordillera Urubamba, Cusco, is distinct from all other members of open-panicled Poa's by having glabrous lemmas with a smooth and glabrous callus, and notably small anthers. The type material for the name Poa adusta is discussed and a lectotype is selected.


ResúmenAportamos una lista actualizada y una clave para las 30 especies de Poa con panículas abiertas de Perú que incluye las especies de Dissanthelium y Aphanelytrum anteriormente circunscritas, nuevos registros de taxones y tres especies no descritas. Poa compressa, Poa grisebachii, y Poa leioclada se registran para Perú por primera vez. Un número de especies son sinonimizadas: Poa carazensis, Poa ferreyrae y Poa tovarii son sinonimizadas bajo el nombre de Poa fibrifera; Poa adusta (tentativamente) y Poa pilgeri son sinonimizadas bajo el nombre de Poa candamoana; Poa superata es sinonimizada bajo Poa grisebachii; y Poa paramoensis es sinonimizada bajo Poa huancavelicae. Dentro de este tratamiento se incluyen dos especies nuevas, Poa ramoniana, Poa tayacajaensis y Poa urubambensis que a continuación se describen e ilustran. Poa ramoniana, que se encuentra creciendo en pastizales de alta elevación cercanos a lagos en la Puna de Junín, es similar a la forma pequeña de Poa glaberrima, pero se diferencia por tener rizomas y crecer hasta sólo 5 cm de altura. Poa tayacajaensis, que se encuentra en matorrales de las laderas andinas de Huancavelica y Huánuco, tiene un parecido a Poa aequatoriensis, pero se diferencia por tener lemas cortas que son pubescentes entre las venas, vainas densamente escabrosas con suaves gargantas glabras, y lígulas cortas. Poa urubambensis, un elemento común de sotobosque no perturbado de los bosques de Polylepis de la Cordillera Urubamba, Cusco, se distingue de todos los otros miembros de Poa con panícula-abierta por tener lemas glabras con un callo suave y glabro, y sus notables anteras pequeñas. El material tipo del nombre Poa adusta es discutido y un lectotipo es seleccionado.

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