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1.
Immunity ; 56(1): 125-142.e12, 2023 01 10.
Artículo en Inglés | MEDLINE | ID: mdl-36630911

RESUMEN

During metastasis, cancer cells invade, intravasate, enter the circulation, extravasate, and colonize target organs. Here, we examined the role of interleukin (IL)-22 in metastasis. Immune cell-derived IL-22 acts on epithelial tissues, promoting regeneration and healing upon tissue damage, but it is also associated with malignancy. Il22-deficient mice and mice treated with an IL-22 antibody were protected from colon-cancer-derived liver and lung metastasis formation, while overexpression of IL-22 promoted metastasis. Mechanistically, IL-22 acted on endothelial cells, promoting endothelial permeability and cancer cell transmigration via induction of endothelial aminopeptidase N. Multi-parameter flow cytometry and single-cell sequencing of immune cells isolated during cancer cell extravasation into the liver revealed iNKT17 cells as source of IL-22. iNKT-cell-deficient mice exhibited reduced metastases, which was reversed by injection of wild type, but not Il22-deficient, invariant natural killer T (iNKT) cells. IL-22-producing iNKT cells promoting metastasis were tissue resident, as demonstrated by parabiosis. Thus, IL-22 may present a therapeutic target for prevention of metastasis.


Asunto(s)
Interleucinas , Neoplasias Hepáticas , Células T Asesinas Naturales , Animales , Ratones , Células Endoteliales/metabolismo , Interleucinas/metabolismo , Neoplasias Hepáticas/patología , Neoplasias Hepáticas/secundario , Ratones Endogámicos C57BL , Células T Asesinas Naturales/metabolismo , Neoplasias Colorrectales/metabolismo , Interleucina-22
2.
Cladistics ; 39(2): 71-100, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36701490

RESUMEN

Crotalines (pitvipers) in the Americas are distributed from southern Canada to southern Argentina, and are represented by 13 genera and 163 species that constitute a monophyletic group. Their phylogenetic relationships have been assessed mostly based on DNA sequences, while morphological data have scarcely been used for phylogenetic inquiry. We present a total-evidence phylogeny of New World pitvipers, the most taxon/character comprehensive phylogeny to date. Our analysis includes all genera, morphological data from external morphology, cranial osteology and hemipenial morphology, and DNA sequences from mitochondrial and nuclear genes. We performed analyses with parsimony as an optimality criterion, using different schemes for character weighting. We evaluated the contribution of the different sources of characters to the phylogeny through analyses of reduced datasets and calculation of weighted homoplasy and retention indexes. We performed a morphological character analysis to identify synapomorphies for the main clades. In terms of biogeography, our results support a single colonization event of the Americas by pitvipers, and a cladogenetic event into a Neotropical clade and a North American/Neotropical clade. The results also shed light on the previously unstable position of some taxa, although they could not sufficiently resolve the position of Bothrops lojanus, which may lead to the paraphyly of either Bothrops or Bothrocophias. The morphological character analyses demonstrated that an important phylogenetic signal is contained in characters related to head scalation, the jaws and the dorsum of the skull, and allowed us to detect morphological convergences in external morphology associated with arboreality.


Asunto(s)
Bothrops , Crotalinae , Viperidae , Animales , Filogenia , Viperidae/genética , Crotalinae/genética , Evolución Biológica , Secuencia de Bases , Bothrops/genética
3.
Molecules ; 28(3)2023 Jan 22.
Artículo en Inglés | MEDLINE | ID: mdl-36770768

RESUMEN

Xanthylium derivatives are curcumin analogs showing photochromic properties. Similarly, to anthocyanins, they follow the same multistate network of chemical species that are reversibly interconverted by external stimuli. In the present work, two new asymmetric monocarbonyl analogues of curcumin, 4-(4-hydroxy-3-metoxybenzylidene)-1,2,3,4-tetrahydroxanthylium chloride (compound 3) and 4-(4-hydroxybenzylidene)-6-methoxy-1,2,3,4-tetrahydroxanthylium chloride (compound 4) were synthesized, and their photochromic and biological properties were investigated. The UV-Vis spectroscopy and the direct and reverse pH-jumps studies confirmed the halochromic properties and the existence of different molecular species. A network of chemical reactions of these species was proposed. Furthermore, the antiproliferative properties of both compounds were evaluated using P19 murine embryocarcinoma cells and compared with each other. The results demonstrate that both new xanthylium derivatives modify the progression through the cell cycle of P19 cells, which translates into a significant antiproliferative effect. The effect of the methoxy group position is discussed and several checkpoint proteins are advanced as putative targets.


Asunto(s)
Antineoplásicos , Curcumina , Animales , Ratones , Curcumina/química , Relación Estructura-Actividad , Antocianinas , Cloruros , Antineoplásicos/química
4.
J Dairy Sci ; 105(1): 866-876, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34763920

RESUMEN

Mastitis has a high incidence in dairy cows. Experimental infection with Escherichia coli increased the number of leukocytes in milk and the gene expression of the chemokine receptor CXCR4 in mammary gland tissues. A link between CXCR4 expression and lipopolysaccharide sensing was demonstrated in other species using in vitro models. The receptor that binds the chemokine stomal cell-derived factor 1 might be associated with the inflammatory response in bovine mammary glands. However, studies in cows are rare, and data on the localization of CXCR4 in bovine mammary glands and its distribution in bovine leukocytes are lacking. Fatty acids (FA) affect the inflammatory response. In human peripheral blood monocytes, exposure to conjugated linoleic acids (CLA) decreases the expression of CXCR4, leading to a decreased inflammatory response in these cells. In this study, we analyzed the expression of CXCR4 in the mammary glands of dairy cows by immunohistochemistry (n = 5) and laser capture microdissection followed by qualitative PCR (n = 3). We characterized the surface expression of CXCR4 on bovine leukocytes, including monocyte subpopulations, first by flow cytometry (n = 5) and then confirmed these results by Western blotting (n = 3). Rumen fistulated dairy cows (n = 4; 126 ± 4 d in milk) were fitted with abomasal infusion tubes, arranged in a 4 × 4 Latin square design, and supplemented for 6 wk twice daily with rising doses of FA followed by a 3-wk washout period. Then, CXCR4 expression on leukocytes was analyzed. The cows received a corn-based diet and were supplemented with coconut oil delivering medium-chain FA (38 g/d), linseed-safflower oil mix delivering n-3 FA (EFA, 39 g of linseed oil and 2 g of safflower oil per day), Lutalin (cis-9,trans-11 and trans-10,cis-12 CLA, 5 g/d; BASF), and EFA + CLA. In the bovine mammary gland, the epithelial cells of the lactiferous duct, but not alveolar epithelial cells, showed clear CXCR4 protein and mRNA signals. Among the leukocyte subsets, monocytes displayed the highest percentage of CXCR4-positive cells (87%), whereas circulating neutrophils showed almost no CXCR4 surface expression (3%) but stored the receptor intracellularly. The percentage of CXCR4-positive leukocytes was not affected by the different FA supplements, but FA supplementation reduced the receptor abundance per cell (40% on average). In conclusion, CXCR4 was clearly detected in the lactiferous duct cells of the mammary gland but not in the alveolar epithelial cells. Compared with other leukocytes, bovine monocytes showed the highest signal intensity of CXCR4 on their surface, whereas granulocytes stored CXCR4 intracellularly. Supplementation with all the FA reduced the surface expression of CXCR4 per leukocyte and could therefore potentially affect the inflammatory status associated with the surface expression of CXCR4. The importance of our observations should be verified in cows with mastitis in the future.


Asunto(s)
Lactancia , Leucocitos , Glándulas Mamarias Animales/metabolismo , Receptores CXCR4/metabolismo , Animales , Bovinos , Dieta , Suplementos Dietéticos , Ácidos Grasos , Femenino , Ácidos Linoleicos Conjugados , Leche
5.
Accredit Qual Assur ; 27(5): 275-288, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36061230

RESUMEN

The COVID-19 pandemic posed new and manifold challenges to organizations and their operations worldwide. Conformity assessment bodies (CABs), such as testing or medical laboratories, certification, and inspection bodies, were also affected by the associated disruptions. Their role in this crisis is highly relevant, as CABs are essential pillars of the quality infrastructure: their activities ensure that products and services meet requirements as defined in standards and regulations, thereby contributing to their safety and reliability. The question arises of how CABs and their operations were affected by the pandemic and how they responded. To this end, we present the results of an international survey of 986 CABs of all types in Germany, the UK, Italy, and New Zealand. Overall, CABs reported, on average, a reduction in demand for their services during the pandemic, facing restrictions in all countries. In addition, the pandemic had an overall negative impact on the CABs' investment and innovation activities. However, investments in digital infrastructure were increased as a countermeasure, with CABs reporting a higher need for digitalization. The paper highlights and discusses results from in-depth analyses relevant to policymakers and industry alike.

6.
Clin Chem ; 67(10): 1395-1405, 2021 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-34322698

RESUMEN

BACKGROUND: Circulating tumor cell (CTC) analysis is highly promising for liquid biopsy-based molecular diagnostics. We undertook a comprehensive molecular analysis of in vivo isolated CTCs in breast cancer (BrCa). METHODS: In vivo isolated CTCs from 42 patients with early and 23 patients with metastatic breast cancer (MBC) were prospectively collected and analyzed for gene expression, DNA mutations, and DNA methylation before and after treatment. 19 healthy donor (HD) samples were analyzed as a control group. In identical blood draws, CTCs were enumerated using CellSearch® and characterized by direct IF staining. RESULTS: All 19 HD samples were negative for CK8, CK18, CK19, ERBB2, TWIST1, VEGF, ESR1, PR, and EGFR expression, while CD44, CD24, ALDH1, VIM, and CDH2 expression was normalized to B2M (reference gene). At least one gene was expressed in 23/42 (54.8%) and 8/13 (61.5%) CTCs in early BrCa before and after therapy, and in 20/23 (87.0%) and 5/7 (71.4%) MBC before and after the first cycle of therapy. PIK3CA mutations were detected in 11/42 (26.2%) and 3/13 (23.1%) in vivo isolated CTCs in early BrCa before and after therapy, and in 11/23 (47.8%) and 2/7 (28.6%) MBC, respectively. ESR1 methylation was detected in 5/32 (15.7%) and 1/10 (10.0%) CTCs in early BrCa before and after therapy, and in 3/15(20.0%) MBC before the first line of therapy. The comprehensive molecular analysis of CTC revealed a higher sensitivity in relation to CellSearch or IF staining when based on creatine kinase selection. CONCLUSIONS: In vivo-CTC isolation in combination with a comprehensive molecular analysis at the gene expression, DNA mutation, and DNA methylation level comprises a highly powerful approach for molecular diagnostic applications using CTCs.


Asunto(s)
Neoplasias de la Mama , Células Neoplásicas Circulantes , Biomarcadores de Tumor/genética , Biomarcadores de Tumor/metabolismo , Neoplasias de la Mama/patología , Metilación de ADN , Molécula de Adhesión Celular Epitelial/genética , Femenino , Humanos , Biopsia Líquida , Células Neoplásicas Circulantes/patología
7.
Clin Chem ; 67(4): 631-641, 2021 03 31.
Artículo en Inglés | MEDLINE | ID: mdl-33491069

RESUMEN

BACKGROUND: Multiple technologies are available for detection of circulating tumor cells (CTCs), but standards to evaluate their technical performance are still lacking. This limits the applicability of CTC analysis in clinic routine. Therefore, in the context of the CANCER-ID consortium, we established a platform to assess technical validity of CTC detection methods in a European multi-center setting using non-small cell lung cancer (NSCLC) as a model. METHODS: We characterized multiple NSCLC cell lines to define cellular models distinct in their phenotype and molecular characteristics. Standardized tumor-cell-bearing blood samples were prepared at a central laboratory and sent to multiple European laboratories for processing according to standard operating procedures. The data were submitted via an online tool and centrally evaluated. Five CTC-enrichment technologies were tested. RESULTS: We could identify 2 cytokeratin expressing cell lines with distinct levels of EpCAM expression: NCI-H441 (EpCAMhigh, CKpos) and NCI-H1563 (EpCAMlow, CKpos). Both spiked tumor cell lines were detected by all technologies except for the CellSearch system that failed to enrich EpCAMlow NCI-H1563 cells. Mean recovery rates ranged between 49% and 75% for NCI-H411 and 32% and 76% for NCI-H1563 and significant differences were observed between the tested methods. CONCLUSIONS: This multi-national proficiency testing of CTC-enrichment technologies has importance in the establishment of guidelines for clinically applicable (pre)analytical workflows and the definition of minimal performance qualification requirements prior to clinical validation of technologies. It will remain in operation beyond the funding period of CANCER-ID in the context of the European Liquid Biopsy Society (ELBS).


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Células Neoplásicas Circulantes , Biomarcadores de Tumor , Carcinoma de Pulmón de Células no Pequeñas/diagnóstico , Línea Celular Tumoral , Humanos , Neoplasias Pulmonares/diagnóstico
8.
Mol Phylogenet Evol ; 141: 106615, 2019 12.
Artículo en Inglés | MEDLINE | ID: mdl-31520778

RESUMEN

The radiation of Palearctic green toads (Bufotes) holds great potential to evaluate the role of hybridization in phylogeography at multiple stages along the speciation continuum. With fifteen species representing three ploidy levels, this model system is particularly attractive to examine the causes and consequences of allopolyploidization, a prevalent yet enigmatic pathway towards hybrid speciation. Despite substantial efforts, the evolutionary history of this species complex remains largely blurred by the lack of consistency among the corresponding literature. To get a fresh, comprehensive view on Bufotes phylogeography, here we combined genome-wide multilocus analyses (RAD-seq) with an extensive compilation of mitochondrial, genome size, niche modelling, distribution and phenotypic (bioacoustics, morphometrics, toxin composition) datasets, representing hundreds of populations throughout Eurasia. We provide a fully resolved nuclear phylogeny for Bufotes and highlight exceptional cyto-nuclear discordances characteristic of complete mtDNA replacement (in 20% of species), mitochondrial surfing during post-glacial expansions, and the formation of homoploid hybrid populations. Moreover, we traced the origin of several allopolyploids down to species level, showing that all were exclusively fathered by the West Himalayan B. latastii but mothered by several diploid forms inhabiting Central Asian lowlands, an asymmetry consistent with hypotheses on mate choice and Dobzhansky-Muller incompatibilities. Their intermediate call phenotypes potentially allowed for rapid reproductive isolation, while toxin compositions converged towards the ecologically-closest parent. Across the radiation, we pinpoint a stepwise progression of reproductive isolation through time, with a threshold below which hybridizability is irrespective of divergence (<6My), above which species barely admix and eventually evolve different mating calls (6-10My), or can successfully cross-breed through allopolyploidization (>15My). Finally, we clarified the taxonomy of Bufotes (including genetic analyses of type series) and formally described two new species, B. cypriensis sp. nov. (endemic to Cyprus) and B. perrini sp. nov. (endemic to Central Asia). Embracing the genomic age, our framework marks the advent of a new exciting era for evolutionary research in these iconic amphibians.


Asunto(s)
Evolución Biológica , Bufonidae/fisiología , Animales , Bufonidae/clasificación , Bufonidae/genética , ADN Mitocondrial/genética , Especiación Genética , Tamaño del Genoma , Genoma Mitocondrial , Genómica , Hibridación Genética , Mitocondrias/genética , Fenotipo , Filogenia , Filogeografía , Análisis de Componente Principal , Factores de Tiempo
9.
Int J Mol Sci ; 20(11)2019 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-31195708

RESUMEN

Diets of dairy cows are often based on maize silage (MS), delivering lower amounts of n-3 fatty acids (FA) compared to grass silage-based diets. The fatty acid composition of the cell membrane can affect the cell function. We evaluated the effects of an MS-based diet on bovine red blood cell (RBC) membrane FA composition and dietary effects on controlled ATP release of RBC. In trial 1, German Holstein cows were fed an MS-based total mixed ration for 24 weeks. The FA composition of RBC membranes from repeatedly taken blood samples was analysed in addition to the abundance of the RBC membrane protein flotillin-1, which is involved in, for example, cell signalling. In trial 2, four rumen fistulated MS-fed cows were abomasally infused in a 4 × 4 Latin square model with three successively increasing lipid dosages (coconut oil, linseed-safflower oil mix (EFA; rich in n-3 FA), Lutalin®, providing conjugated linoleic acids (CLA) or the combination of the supplements, EFA + CLA) for six weeks, followed by a three-week washout period. In trial 2, we analysed RBC ATP release, flotillin-1, and the membrane protein abundance of pannexin-1, which is involved in ATP release as the last part of a signalling cascade. In trial 1, the total amount of n-3 FA in RBC membranes decreased and the flotillin-1 abundance increased over time. In trial 2, the RBC n-3 FA amount was higher after the six-week infusion period of EFA or EFA + CLA. Furthermore, depending on the dosage of FA, the ATP release from RBC increased. The abundance of flotillin-1 and pannexin-1 was not affected in trial 2. It is concluded that changes of the membrane FA composition influence the RBC function, leading to altered ATP release from intact bovine RBC.


Asunto(s)
Adenosina Trifosfato/metabolismo , Industria Lechera , Dieta , Membrana Eritrocítica/metabolismo , Ácidos Grasos/farmacología , Animales , Bovinos , Conexinas/metabolismo , Suplementos Dietéticos , Membrana Eritrocítica/efectos de los fármacos , Femenino , Proteínas de la Membrana/metabolismo
10.
Prep Biochem Biotechnol ; 46(2): 208-13, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-25806650

RESUMEN

Deterioration of health is a problem in modern space flight business. In order to develop countermeasures, research has been done on human bodies and also on single cells. Relevant experiments on human cells in vitro are feasible when microgravity is simulated by devices such as the Random Positioning Machine or generated for a short time during parabolic flights. However, they become difficult in regard to performance and interpretation when long-term experiments are designed that need a prolonged stay on the International Space Station (ISS). One huge problem is the transport of living cells from a laboratory on Earth to the ISS. For this reason, mainly rapidly growing, rather robust human cells such as cancer cells, embryonic cells, or progenitor cells have been investigated on the ISS up to now. Moreover, better knowledge on the behavior of normal mature cells, which mimic the in vivo situation, is strongly desirable. One solution to the problem could be the use of redifferentiable cells, which grow rapidly and behave like cancer cells in plain medium, but are reprogrammed to normal cells when substances like retinoic acid are added. A list of cells capable of redifferentiation is provided, together with names of suitable drugs, in this review.


Asunto(s)
Técnicas de Cultivo de Célula/métodos , Vuelo Espacial , Animales , Diferenciación Celular , Células Cultivadas , Drosophila/citología , Humanos , Células Tumorales Cultivadas , Ingravidez
11.
Zootaxa ; 3964(2): 228-44, 2015 Jun 02.
Artículo en Inglés | MEDLINE | ID: mdl-26249433

RESUMEN

Three new blind snake species of the genus Epictia are described based on material collected in the Peruvian Regions Amazonas, Cajamarca and La Libertad. All three species are well differentiated from all congeners based on characteristics of their morphology and coloration. They share 10 scale rows around the middle of the tail and possess two supralabials with the anterior one in broad contact with the supraocular. Epictia septemlineata sp. nov. has 16 subcaudal scales, 257 mid-dorsal scale rows, a yellowish-white rostral, and a black terminal spine. Epictia vanwallachi sp. nov. exhibits 16 subcaudals, 188 mid-dorsal scale rows, a grayish-brown rostral, and a yellow terminal spine. Epictia antoniogarciai sp. nov. features 14-18 subcaudals, 195-208 mid-dorsal scale rows, a bright yellow or yellowish-white rostral, and the terminal spine and terminal portion of the tail yellow. All three species were collected in the interandean dry forest valleys of the Marañón River and its tributaries. This region is an area of endemism and warrants further attention from systematic and conservation biologists.


Asunto(s)
Serpientes/clasificación , Distribución Animal , Estructuras Animales/anatomía & histología , Estructuras Animales/crecimiento & desarrollo , Animales , Tamaño Corporal , Ecosistema , Femenino , Bosques , Masculino , Tamaño de los Órganos , Perú , Serpientes/anatomía & histología , Serpientes/crecimiento & desarrollo
12.
Zootaxa ; 5418(4): 301-327, 2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-38480354

RESUMEN

Pseudogonatodes is a poorly known genus of small bodied, diurnal, ground-dwelling geckos widely distributed in northern South America. No additional species have been described in over two decades. Herein we describe a new species from the eastern slope of the Cordillera de Mrida in the Venezuelan Andes. The new species is readily diagnosable morphologically from the other seven recognized species of Pseudogonatodes by having a single postnasal scalea putative autapomorphy. Furthermore, it is characterized by a unique combination of phenotypic characters that includes granular dorsal scales, three large postrostrals, five to six loreals, mental U-shaped, four to six postmentals, 2629 ventrals between anterior levels of fore- and hind limbs, third lamella under fourth toe not distinctly enlarged, and subcaudal pattern 11. In addition to characterizing the external morphology, we present a description of the skull, based on 3D digital models reconstructed from high resolution computed microtomography scans. The discovery of this new species highlights the still underestimated diversity of this group of Neotropical dwarf geckos and underscores the need for further studies on its systematics and taxonomy.


Asunto(s)
Lagartos , Animales , Estructuras Animales/anatomía & histología , Distribución Animal , América del Sur , Serpientes
13.
EMBO Mol Med ; 2024 Jun 19.
Artículo en Inglés | MEDLINE | ID: mdl-38898234

RESUMEN

Circulating tumor DNA (ctDNA) is the cornerstone of liquid biopsy diagnostics, revealing clinically relevant genomic aberrations from blood of cancer patients. Genomic analysis of single circulating tumor cells (CTCs) could provide additional insights into intra-patient heterogeneity, but it requires whole-genome amplification (WGA) of DNA, which might introduce bias. Here, we describe a novel approach based on mass spectrometry for mutation detection from individual CTCs not requiring WGA and complex bioinformatics pipelines. After establishment of our protocol on tumor cell line-derived single cells, it was validated on CTCs of 33 metastatic melanoma patients and the mutations were compared to those obtained from tumor tissue and ctDNA. Although concordance with tumor tissue was superior for ctDNA over CTC analysis, a larger number of mutations were found within CTCs compared to ctDNA (p = 0.039), including mutations in melanoma driver genes, or those associated with resistance to therapy or metastasis. Thus, our results demonstrate proof-of-principle data that CTC analysis can provide clinically relevant genomic information that is not redundant to tumor tissue or ctDNA analysis.

14.
Zootaxa ; 3745: 263-95, 2013 Dec 04.
Artículo en Inglés | MEDLINE | ID: mdl-25113348

RESUMEN

We describe two new species of Ameiva Meyer, 1795 from the dry forest of the Northern Peruvian Andes. The new species Ameiva nodam sp. nov. and Ameiva aggerecusans sp. nov. share a divided frontal plate and are differentiated from each other and from their congeners based on genetic (12S and 16S rRNA genes) and morphological characteristics. A. nodam sp. nov. has dilated postbrachials, a maximum known snout-vent length of 101 mm, 10 longitudinal rows of ventral plates, 86-113 midbody granules, 25-35 lamellae under the fourth toe, and a color pattern with 5 longitudinal yellow stripes on the dorsum. Ameiva aggerecusans sp. nov. has not or only hardly dilated postbrachials, a maximum known snout-vent length of 99.3 mm, 10-12 longitudinal rows of ventral plates, 73-92 midbody granules, 31-39 lamellae under the fourth toe, and the females and juveniles of the species normally exhibit a cream-colored vertebral stripe on a dark dorsum ground color. We provide information on the intraspecific variation and distribution of A. concolor. Furthermore, we provide information on the environmental niches of the taxa and test for niche conservatism. 


Asunto(s)
Lagartos/clasificación , Distribución Animal , Estructuras Animales/anatomía & histología , Animales , ADN Ribosómico/genética , Ecosistema , Femenino , Lagartos/anatomía & histología , Lagartos/genética , Masculino , Datos de Secuencia Molecular , Perú , Filogenia , Árboles
15.
Zookeys ; 1175: 187-221, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37636530

RESUMEN

Neacomys is a genus of small spiny or bristly sigmodontine rodents that are common components of mammalian faunas in multiple biomes on Central and South America. Recent studies on this group have demonstrated that there is cryptic diversity yet to be discovered within currently recognized species that have not received comprehensive revisions, as well as in areas that have been overlooked. Here we ratify this assertion by describing a new species previously misidentified as the Narrow-footed Spiny Mouse (Neacomystenuipes) from the Chocó biogeographic region in northwestern Ecuador, Neacomysmarci Brito & Tinoco, sp. nov. Distinctiveness of this entity is supported by the combination of the following morphological characters: small size (head-body length 65-85 mm); long tail (69-126% longer than head-body length); pale buff-colored but gray-based belly fur; white throat; hypothenar pad usually absent; long nasals; and a condylar process higher than the coronoid process. Likewise genetic distance analyses and phylogenetic reconstructions based on cytochrome-b (Cytb) sequence data indicate a clear divergence from typical populations of N.tenuipes, and a sister relationship between them. The results presented here increase the diversity of Neacomys to 24 species, placing it among the most diverse genera within the sigmodontine rodents.

16.
J Morphol ; 284(8): e21617, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37458083

RESUMEN

The skull of vipers is a highly kinetic anatomical structure involved in envenomating and consuming of prey. Morphological knowledge about the viperid skull is based on studies on some groups of species, but information on its variation within the whole family and its functional morphology is still scarce. In this study, we aimed to explore variation in skull morphology among species of the three subfamilies of Viperidae, and test whether that variation correlates with macrohabitat and diet. We performed quantitative analyses of the viperid skull based on broad taxonomic sampling and two methodological approaches: linear and geometric morphometrics. The results of both approaches showed that much of the variation lies in differences of shape and relative size of the premaxilla, the nasals, the frontals, and the parietals. The results indicated that phylogeny and size influence the shape of the skull, but we also found evidence of morphological differentiation between arboreal and terrestrial species and in species with mammal specialist diet. Our findings imply that, besides evolutionary allometry and phylogenetic signal, demands of particular diets coupled with use of certain habitats have in part shaped morphological evolution of the viperid skull.


Asunto(s)
Viperidae , Animales , Filogenia , Viperidae/anatomía & histología , Cráneo/anatomía & histología , Cabeza , Ecosistema , Evolución Biológica , Mamíferos
17.
Viruses ; 15(9)2023 09 19.
Artículo en Inglés | MEDLINE | ID: mdl-37766357

RESUMEN

Immunosorbent turnip vein clearing virus (TVCV) particles displaying the IgG-binding domains D and E of Staphylococcus aureus protein A (PA) on every coat protein (CP) subunit (TVCVPA) were purified from plants via optimized and new protocols. The latter used polyethylene glycol (PEG) raw precipitates, from which virions were selectively re-solubilized in reverse PEG concentration gradients. This procedure improved the integrity of both TVCVPA and the wild-type subgroup 3 tobamovirus. TVCVPA could be loaded with more than 500 IgGs per virion, which mediated the immunocapture of fluorescent dyes, GFP, and active enzymes. Bi-enzyme ensembles of cooperating glucose oxidase and horseradish peroxidase were tethered together on the TVCVPA carriers via a single antibody type, with one enzyme conjugated chemically to its Fc region, and the other one bound as a target, yielding synthetic multi-enzyme complexes. In microtiter plates, the TVCVPA-displayed sugar-sensing system possessed a considerably increased reusability upon repeated testing, compared to the IgG-bound enzyme pair in the absence of the virus. A high coverage of the viral adapters was also achieved on Ta2O5 sensor chip surfaces coated with a polyelectrolyte interlayer, as a prerequisite for durable TVCVPA-assisted electrochemical biosensing via modularly IgG-assembled sensor enzymes.


Asunto(s)
Colorantes Fluorescentes , Polietilenglicoles , Polielectrolitos , Inmunoglobulina G
18.
PeerJ ; 10: e13211, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35462758

RESUMEN

The Andean cloud forests of Ecuador are home to several endemic mammals. Members of the Thomasomyini rodents are well represented in the Andes, with Thomasomys being the largest genus (47 species) of the subfamily Sigmodontinae. Within this tribe, however, there are genera that have escaped a taxonomic revision, and Chilomys Thomas, 1897, constitutes a paradigmatic example of these "forgotten" Andean cricetids. Described more than a century ago, current knowledge of this externally unmistakable montane rodent is very limited, and doubts persist as to whether or not it is monotypic. After several years of field efforts in Ecuador, a considerable quantity of specimens of Chilomys were collected from various localities representing both Andean chains. Based on an extensive genetic survey of the obtained material, we can demonstrate that what is currently treated as C. instans in Ecuador is a complex comprising at least five new species which are described in this paper. In addition, based on these noteworthy new evidence, we amend the generic diagnosis in detail, adding several key craniodental traits such as incisor procumbency and microdonty. These results indicate that Chilomys probably has a hidden additional diversity in large parts of the Colombian and Peruvian territories, inviting a necessary revision of the entire genus.


Asunto(s)
Arvicolinae , Roedores , Animales , Ecuador , Sigmodontinae , Bosques
19.
PeerJ ; 10: e14066, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36196397

RESUMEN

We have discovered a spectacular new species of frog in the genus Hyloscirtus, belonging to the H. larinopygion species group. The adult female is characterized by a mostly black body with large bright red spots on the dorsal and ventral surface, extremities, and toe pads. The adult male is unknown. Small juveniles are characterized by a yellow body with variable black markings on the flanks; while one larger juvenile displayed irregular orange or yellow marks on a black background color, with light orange or yellow toe pads. Additional distinctive external morphological features such as cloacal ornamentation are described, and some osteological details are imaged and analyzed. The performed phylogeny places the new species as the sister to a clade consisting of ten taxa, all of which are part of the H. larinopygion group. We use genetic distances to fit the new species into a published time-calibrated phylogeny of this group; our analysis based on the published chronology suggests that the divergence of the new species from its known congeners pre-dates the Quaternary period. The new species is currently only known only from Cerro Mayordomo, in Fundación EcoMinga´s Machay Reserve, at 2,900 m in the eastern Andes of Tungurahua province, Ecuador, near the southern edge of Los Llanganates National Park, but its real distribution may be larger.


Asunto(s)
Anuros , Parques Recreativos , Masculino , Femenino , Animales , Anuros/anatomía & histología , Ecuador , Distribución Animal , Filogenia
20.
Anat Rec (Hoboken) ; 304(10): 2279-2291, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-33650212

RESUMEN

"Scolecophidians" are traditionally known for their several skull and lower jaw autapomorphies, being conspicuously different from alethinophidian snakes in terms of skull shape and function. Although typically known for the absence of any kinetic joint in the skull dermatocranium and neurocranium-mostly due to an adaptation to fossorial habit, literature data have previously suggested a possible cranial kinesis for individuals of Afrotyphlops punctatus based on observations of live and preserved individuals. Given such observations, herein we aim to describe in detail the skull of A. punctatus based on CT-scan images of five specimens, evaluating the skull morphology and inferred function, and also providing valuable discussion on the skull osteology of the genus. Our results suggest that the skull of A. punctatus is similar to other blindsnakes in lacking any trace of snout, or even a frontal-parietal articulation. We also discuss possible osteological data that might be systematically relevant for Typhlopidae both interspecifically and intergenerically.


Asunto(s)
Cinesis , Cráneo , Animales , Cabeza , Humanos , Mandíbula , Cráneo/diagnóstico por imagen , Serpientes
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