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1.
Sci Data ; 11(1): 782, 2024 Jul 16.
Artículo en Inglés | MEDLINE | ID: mdl-39013892

RESUMEN

We present a flora and fauna dataset for the Mira-Mataje binational basins. This is an area shared between southwestern Colombia and northwestern Ecuador, where both the Chocó and Tropical Andes biodiversity hotspots converge. We systematized data from 120 sources in the Darwin Core Archive (DwC-A) standard and geospatial vector data format for geographic information systems (GIS) (shapefiles). Sources included natural history museums, published literature, and citizen science repositories across 13 countries. The resulting database has 33,460 records from 6,821 species, of which 540 have been recorded as endemic, and 612 as threatened. The diversity represented in the dataset is equivalent to 10% of the total plant species and 26% of the total terrestrial vertebrate species in both hotspots. The dataset can be used to estimate and compare biodiversity patterns with environmental parameters and provide value to ecosystems, ecoregions, and protected areas. The dataset is a baseline for future assessments of biodiversity in the face of environmental degradation, climate change, and accelerated extinction processes.


Asunto(s)
Biodiversidad , Plantas , Ecuador , Animales , Colombia , Vertebrados , Sistemas de Información Geográfica , Ecosistema , Cambio Climático , Conservación de los Recursos Naturales , Clima Tropical
2.
Front Neuroanat ; 17: 1128193, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36992795

RESUMEN

The analysis of the topography of brain neuromodulation following transcranial alternating current (AC) stimulation is relevant for defining strategies directed to specific nuclei stimulation in patients. Among the different procedures of AC stimulation, temporal interference (tTIS) is a novel method for non-invasive neuromodulation of specific deep brain targets. However, little information is currently available about its tissue effects and its activation topography in in vivo animal models. After a single session (30 min, 0.12 mA) of transcranial alternate current (2,000 Hz; ES/AC group) or tTIS (2,000/2,010 Hz; Es/tTIS group) stimulation, rat brains were explored by whole-brain mapping analysis of c-Fos immunostained serial sections. For this analysis, we used two mapping methods, namely density-to-color processed channels (independent component analysis (ICA) and graphical representation (MATLAB) of morphometrical and densitometrical values obtained by density threshold segmentation. In addition, to assess tissue effects, alternate serial sections were stained for glial fibrillary acidic protein (GFAP), ionized calcium-binding adapter molecule 1 (Iba1), and Nissl. AC stimulation induced a mild superficial increase in c-Fos immunoreactivity. However, tTIS stimulation globally decreased the number of c-Fos-positive neurons and increased blood brain barrier cell immunoreactivity. tTIS also had a stronger effect around the electrode placement area and preserved neuronal activation better in restricted areas of the deep brain (directional stimulation). The enhanced activation of intramural blood vessels' cells and perivascular astrocytes suggests that low-frequency interference (10 Hz) may also have a trophic effect.

3.
Front Vet Sci ; 10: 1101024, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36876003

RESUMEN

In this study, we describe in detail the anatomy of nuclei involved in seasonal fertility regulation (SFR) in ewes. For this purpose, the intergeniculate leaflet of the visual thalamus, the caudal hypothalamic arcuate nucleus, and suprachiasmatic, paraventricular and supraoptic nuclei of the rostral hypothalamus were morphometrically and qualitatively analyzed in Nissl-stained serial sections, in the three anatomical planes. In addition, data were collected on calcium-binding proteins and cell phenotypes after immunostaining alternate serial sections for calretinin, parvalbumin and calbindin. For a complete neuroanatomical study, glial architecture was assessed by immunostaining and analyzing alternate sections for glial fibrillary acidic protein (GFAP) and ionized calcium-binding adapter molecule 1 (IBA1). The results showed a strong microglial and astroglia reaction around the hypothalamic nuclei of interest and around the whole 3rd ventricle of the ewe brain. Moreover, we correlated cytoarchitectonic coordinates of panoramic serial sections with their macroscopic localization and extension in midline sagittal-sectioned whole brain to provide guidelines for microdissecting nuclei involved in SFR.

4.
Zookeys ; 1180: 257-293, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38312322

RESUMEN

The explosive diversity of rainfrogs (Pristimantis spp) reaches its highest levels in the mountains of the Tropical Andes, with remarkable cryptic species mainly in unexplored areas of Ecuador. Based on phylogenetics, morphometric traits, skull osteology and bioacoustics, we describe two new species of Pristimantis, previously confused with Pristimantisgladiator, that belong to the subgenus Trachyphrynus traditionally known as the Pristimantismyersi species group. The two new taxa are closely related, but have allopatric distributions. We discuss the importance of the Quijos and Pastaza River valleys in the diversification along Amazonian slopes of the Ecuadorian Andes.

5.
Mult Scler ; 28(7): 1138-1145, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-35475363

RESUMEN

BACKGROUND: The effect of disease-modifying therapies on severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccine response is unclear. OBJECTIVES: We aim to determine the immunological responses to SARS-CoV-2 in multiple sclerosis (MS) and anti-CD20-treated patients with other autoimmune diseases (AID). METHODS: Humoral and cellular responses we determined before and 30-90 days after vaccination in patients with MS and anti-CD20-treated patients with other AID in two Catalan centers. RESULTS: 457 patients were enrolled. Findings showed that humoral response decreased under anti-CD20s or sphingosine 1-phosphate receptor modulators (S1PRM) and with longer treatment duration and increased after 4.5 months from the last anti-CD20 infusion. Cellular response decreased in S1PRM-treated. Patients on anti-CD20 can present cellular responses even in the absence of antibodies. CONCLUSION: Anti-CD20s and S1PRM modify the immunological responses to SARS-CoV-2 vaccines.


Asunto(s)
COVID-19 , Esclerosis Múltiple , Anticuerpos Antivirales , COVID-19/prevención & control , Vacunas contra la COVID-19 , Humanos , Esclerosis Múltiple/tratamiento farmacológico , SARS-CoV-2 , Vacunación
6.
PeerJ ; 9: e12523, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34966579

RESUMEN

We describe a new species of Neotropical spiny-lizard of the genus Echinosaura from the Imbabura and Carchi Provinces on the western slopes of the Andes in northwestern Ecuador. The new species mostly resembles E. horrida. However, it can be distinguished from all congeners by having keeled enlarged dorsal scales forming a paired vertebral row, two paravertebral series of short oblique rows of projecting scales, and a pair of spine-like scales on temporal and nuchal regions. We also provide a detailed description of the osteology of the skull and pectoral girdle of the new species and present a phylogenetic hypothesis for Echinosaura based on three mitochondrial genes (12S, 16S, ND4) and one nuclear gene (c-mos).

7.
PeerJ ; 9: e11914, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34434655

RESUMEN

We provide several lines of evidence to delimit a new species of Hyloscirtus and define its phylogenetic position inside the Hyloscirtus bogotensis group. The new species is the sister taxon to Hyloscirtus mashpi and is related to a clade formed by H. alytolylax and a putative new species from the province of El Oro in, southwestern Ecuador. Hyloscirtus conscientia sp. nov. is described from the montane forests of the Mira River basin in the extreme northwestern Ecuador. The new species is characterized as follows: tympanic annulus conspicuous, tip of snout in dorsal view subacuminate, middorsal stripe formed by melanophores larger and less dense, dorsal skin with individual iridophores forming dots, scarcely distributed across dorsum. Our study also highlights the importance of the Mira River Valley as a biogeographic barrier; suggesting research efforts north and south of the valley are likely to reveal additional endemic cryptic diversity. Finally, our partnership with Reserva: The Youth Land Trust, Rainforest Trust and EcoMinga Foundation has produced a novel and meaningful way to connect young people with biodiversity discovery and habitat conservation.

8.
Front Neurosci ; 15: 642047, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34393701

RESUMEN

The protective effect of the efferent system against acoustic trauma (AT) has been shown by several experimental approaches, including damage to one ear, sectioning of the olivocochlear bundle (OCB) in the floor of the IV ventricle, and knock-in mice overexpressing outer hair cell (OHC) cholinergic receptors, among others. Such effects have been related to changes in the regulation of the cholinergic efferent system and in cochlear amplification, which ultimately reverse upon protective hearing suppression. In addition to well-known circuits of the brainstem, the descending corticofugal pathway also regulates efferent neurons of the olivary complex. In this study, we applied our recently developed experimental paradigm of multiple sessions of electrical stimulation (ES) to activate the efferent system in combination with noise overstimulation. ABR thresholds increased 1 and 2 days after AT (8-16 kHz bandpass noise at 107 dB for 90 min) recovering at AT + 14 days. However, after multiple sessions of epidural anodal stimulation, no changes in thresholds were observed following AT. Although an inflammatory response was also observed 1 day after AT in both groups, the counts of reactive macrophages in both experimental conditions suggest decreased inflammation in the epidural stimulation group. Quantitative immunocytochemistry for choline acetyltransferase (ChAT) showed a significant decrease in the size and optical density of the efferent terminals 1 day after AT and a rebound at 14 days, suggesting depletion of the terminals followed by a long-term compensatory response. Such a synthesis recovery was significantly higher upon cortical stimulation. No significant correlation was found between ChAT optical density and size of the buttons in sham controls (SC) and ES/AT + 1day animals; however, significant negative correlations were shown in all other experimental conditions. Therefore, our comparative analysis suggests that cochleotopic cholinergic neurotransmission is also better preserved after multisession epidural stimulation.

9.
Brain Sci ; 10(1)2020 Jan 08.
Artículo en Inglés | MEDLINE | ID: mdl-31936259

RESUMEN

Deafness affects the expression and distribution of voltage-dependent potassium channels (Kvs) of central auditory neurons in the short-term, i.e., hours to days, but the consequences in the expression of Kvs after long-term deafness remain unknown. We tested expression and distribution of Kv1.1 and Kv3.1b, key for auditory processing, in the rat cochlear nucleus (CN), and in the inferior colliculus (IC), at 1, 15 and 90 days after mechanical lesion of the cochlea, using a combination of qRT-PCR and Western blot in the whole CN, along with semi-quantitative immunocytochemistry in the AVCN, where the role of both Kvs in excitability control for accurate auditory timing signal processing is well established. Neither Kv1.1/Kv3.1b mRNA or protein expression changed significantly in the CN between 1 and 15 days after deafness. At 90 days post-lesion, however, mRNA and protein expression for both Kvs increased, suggesting that expression regulation of Kv1.1 and Kv3.1b is part of cellular mechanisms for long-term adaptation to auditory input deprivation in the CN. Consistent with these findings, immunocytochemical localization showed increased labeling intensity for both Kvs in the AVCN at day 90 after cochlear lesion, further supporting that up-regulation of Kv1.1 and Kv3.1b in neurons of this CN division, over a long term after auditory deprivation, may be required to adapt intrinsic excitability to altered input. Contrary to findings in the CN, in the IC, expression levels of Kv1.1 and Kv3.1b did not undergo major changes after cochlear lesion. In particular, there was no evidence of long-term up-regulation of neither Kv1.1 or Kv3.1b, supporting that such post-lesion adaptive mechanism may not be needed in the IC. This suggests that post-lesion plastic adaptations to auditory input deprivation are not stereotypical along the auditory pathway.

10.
Front Neurosci ; 13: 356, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31031588

RESUMEN

Rat auditory cortex was subjected to 0.1 mA anodal direct current in seven 10-min sessions on alternate days. Based on the well-known auditory cortex control of olivocochlear regulation through corticofugal projections, auditory brainstem responses (ABRs) were recorded as an indirect test of the effectiveness and reversibility of the multisession protocol of epidural stimulation. Increases of 20-30 dB ABR auditory thresholds shown after epidural stimulation reverted back to control levels 10 min after a single session. However, increases in thresholds revert 4 days after multisession stimulation. Less changes in wave amplitudes and threshold shifts were shown in ABR recorded contralaterally to the electrically stimulated side of the brain. To assess tissue effects of epidural electric stimulation on the brain cortex, well characterized functional anatomical markers of glial cells (GFAP/astrocytes and Iba1/microglial cells) and neurons (c-Fos) were analyzed in alternate serial sections by quantitative immunocytochemistry. Restricted astroglial and microglial reactivity was observed within the cytoarchitectural limits of the auditory cortex. However, interstitial GFAP overstaining was also observed in the ventricular surface and around blood vessels, thus supporting a potential global electrolytic stimulation of the brain. These results correlate with extensive changes in the distribution of c-Fos immunoreactive neurons among layers along sensory cortices after multisession stimulation. Quantitative immunocytochemical analysis supported this idea by showing a significant increase in the number of positive neurons in supragranular layers and a decrease in layer 6 with no quantitative changes detected in layer 5. Our data indicate that epidural stimulation of the auditory cortex induces a reversible decrease in hearing sensitivity due to local, restricted epidural stimulation. A global plastic response of the sensory cortices, also reported here, may be related to electrolytic effects of electric currents.

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