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1.
Rev. biol. trop ; 70(1)dic. 2022.
Article in Spanish | LILACS | ID: biblio-1423034

ABSTRACT

Introducción: Una actividad económica que ha tenido auge en la última década en la altillanura es la forestación de sabanas con alteraciones antrópicas, pero se desconoce su papel en la conservación de las mariposas frugívoras de los bosques de galería dentro de los núcleos forestales. Objetivo: Comparar la diversidad de mariposas frugívoras en plantaciones de eucalipto y bosques de galería, y el papel de las variables ambientales. Métodos: Utilizamos trampas Van Someren-Rydon, dos réplicas de cuatro trampas, en cada uno de los cuatro hábitats muestreados simultáneamente desde diciembre 2020 hasta julio 2021: plantación de eucaliptos de cuatro años; plantación de eucaliptos de seis años; bosque de galería de suelo seco y bosque de galería anegado. También registramos diez variables abióticas, estructurales, alimentarias y de hábitat. Resultados: Recolectamos 227 especímenes de mariposas frugívoras (30 especies, 23 géneros y 5 subfamilias de la familia Nymphalidae). Había más especies en los bosques. Las especies de mariposas variaron más del 50 % entre los hábitats; Satyrinae fue más diversa en las plantaciones. Conclusión: La forestación en esta área proporciona hábitats para algunas especies de mariposas frugívoras de los remanentes de bosques naturales adyacentes. Las forestaciones representan un escenario de alteración intermedia entre las dos unidades de paisaje dominantes en la región.


Introduction: An economic activity that has boomed in the last decade in Colombian highlands is the afforestation of anthropized savannas, but its role in the conservation of fruit-feeding butterflies of gallery forests within forest cores is unknown. Objective: To compare the diversity of fruit-feeding butterflies in eucalyptus plantations and gallery forests, and the role of environmental variables. Methods: We used Van Someren-Rydon traps, two replicates of four traps, on each of four habitats sampled simultaneously from December 2020 to July 2021: four-years-old eucalyptus plantation; six-years-old eucalyptus plantation; dry soil gallery forest and waterlogged gallery forest. We also recorded ten abiotic, structural, food and habitat variables. Results: We collected 227 specimens of fruit-feeding butterflies (30 species, 23 genera, and 5 subfamilies within the family Nymphalidae). There were more species in the forests. The butterfly species varied over 50 % between the habitats; Satyrinae were more diverse in plantations. Conclusion: Afforestation in this area provides habitats for some species of fruit-feeding butterflies from adjacent natural forest remnants. Afforestations represent an intermediate disturbance scenario between the two dominant landscape units in the region.


Subject(s)
Animals , Forestry , Eucalyptus , Lepidoptera , Colombia
2.
Angew Chem Int Ed Engl ; 61(41): e202210043, 2022 10 10.
Article in English | MEDLINE | ID: mdl-35989251

ABSTRACT

Fully substituted peptide/[60]fullerene hexakis-adducts offer an excellent opportunity for multivalent protein recognition. In contrast to monofunctionalized fullerene hybrids, peptide/[60]fullerene hexakis-adducts display multiple copies of a peptide in close spatial proximity and in the three dimensions of space. High affinity peptide binders for almost any target can be currently identified by in vitro evolution techniques, often providing synthetically simpler alternatives to natural ligands. However, despite the potential of peptide/[60]fullerene hexakis-adducts, these promising conjugates have not been reported to date. Here we present a synthetic strategy for the construction of 3D multivalent hybrids that are able to bind with high affinity the E-selectin. The here synthesized fully substituted peptide/[60]fullerene hybrids and their multivalent recognition of natural receptors constitute a proof of principle for their future application as functional biocompatible materials.


Subject(s)
Fullerenes , Biocompatible Materials , E-Selectin , Ligands , Peptides
3.
Chem Commun (Camb) ; 58(9): 1394-1397, 2022 Jan 27.
Article in English | MEDLINE | ID: mdl-34994362

ABSTRACT

We here describe the synthesis and biological evaluation of glycan shields for cell penetrating peptides. A new benzyl alkoxyamine connector was employed for the coupling of two saccharides units in the lateral side chain of individual amino acids in a peptide sequence. The oxyme bond formation with the corresponding glycan aldehydes allowed the preparation of highly glycosylated penetrating peptides with a minimal synthetic effort. Surprisingly, it was found that a four to six saccharide substitution did not decrease uptake efficiency in cells, whereas it significantly improved the toxicity profile of the penetrating peptide. In particular, glucose substitution was confirmed as an optimal glycan shield that showed an excellent in vitro uptake and intracellular localization as well as a superior in vivo biodistribution.


Subject(s)
Cell-Penetrating Peptides/chemistry , Cell-Penetrating Peptides/metabolism , Polysaccharides/chemistry , Amino Acid Sequence , Animals , Cell Membrane Permeability , Glycosylation , HeLa Cells , Heart , Humans , Kidney , Liver , Lung , Mice , Spleen , Structure-Activity Relationship , Tissue Distribution
4.
Chembiochem ; 22(3): 478-480, 2021 02 02.
Article in English | MEDLINE | ID: mdl-32856365

ABSTRACT

Antivirals are now more important than ever. To efficiently inhibit virus replication, antiviral multivalent strategies need sufficient affinity to overcome the excellent matching between the virus and its receptor. This report highlights a phage capsid scaffold strategy that can be used to precisely position sialic acid moieties to inhibit influenza A virus replication.


Subject(s)
Antiviral Agents/pharmacology , Capsid/drug effects , Influenza A virus/drug effects , Antiviral Agents/chemistry , Virus Internalization/drug effects , Virus Replication/drug effects
5.
Front Hum Neurosci ; 14: 611691, 2020.
Article in English | MEDLINE | ID: mdl-33551778

ABSTRACT

A growing volume of research from global data demonstrates that institutional care under conditions of deprivation is profoundly damaging to children, particularly during the critical early years of development. However, how these individuals develop over a life course remains unclear. This study uses data from a survey on the health and development of 420 children mostly under the age of three, placed in 12 infant care institutions between 1958 and 1961 in Zurich, Switzerland. The children exhibited significant delays in cognitive, social, and motor development in the first years of life. Moreover, a follow-up of a subsample of 143 children about 10 years later revealed persistent difficulties, including depression, school related-problems, and stereotypies. Between 2019 and 2021, these formerly institutionalized study participants were located through the Swiss population registry and invited to participate once again in the research project. Now in their early sixties, they are studied for their health, further development, and life-course trajectories. A mixed-methods approach using questionnaires, neuropsychological assessments, and narrative biographical interviews was implemented by a multidisciplinary team. Combining prospective and retrospective data with standardized quantitative and biographical qualitative data allows a rich reconstruction of life histories. The availability of a community sample from the same geographic location, the 1954-1961 cohort of the Zurich Longitudinal Studies, described in detail in a paper in this issue (Wehrle et al., 2020), enables comparison with an unaffected cohort. This article describes the study design and study participants in detail and discusses the potential and limitations of a comparison with a community sample. It outlines a set of challenges and solutions encountered in the process of a lifespan longitudinal study from early childhood into the cusp of old age with a potentially vulnerable sample and summarizes the lessons learned along the way.

6.
Chembiochem ; 20(11): 1400-1409, 2019 06 03.
Article in English | MEDLINE | ID: mdl-30673159

ABSTRACT

The cell membrane regulates the exchange of molecules and information with the external environment. However, this control barrier hinders the delivery of exogenous bioactive molecules that can be applied to correct cellular malfunctions. Therefore, the traffic of macromolecules across the cell membrane represents a great challenge for the development of the next generation of therapies and diagnostic methods. Cell-penetrating peptides are short peptide sequences capable of delivering a broad range of biomacromolecules across the cellular membrane. However, penetrating peptides still suffer from limitations, mainly related to their lack of specificity and potential toxicity. Glycosylation has emerged as a potential promising strategy for the biological improvement of synthetic materials. In this work we have developed a new convergent strategy for the synthesis of penetrating peptides functionalized with glycan residues by an oxime bond connection. The uptake efficiency and intracellular distribution of these glycopeptides have been systematically characterized by means of flow cytometry and confocal microscopy and in zebrafish animal models. The incorporation of these glycan residues into the peptide structure influenced the internalization efficiency and cellular toxicity of the resulting glycopeptide hybrids in the different cell lines tested. The results reported herein highlight the potential of the glycosylation of penetrating peptides to modulate their activity.


Subject(s)
Cell Membrane/metabolism , Cell-Penetrating Peptides , Glycopeptides , Animals , Biological Transport , Cell Line , Cell-Penetrating Peptides/chemical synthesis , Cell-Penetrating Peptides/chemistry , Cell-Penetrating Peptides/metabolism , Glycopeptides/chemical synthesis , Glycopeptides/chemistry , Glycopeptides/metabolism , Glycosylation , Humans , Tissue Distribution , Zebrafish/metabolism
7.
Cortex ; 90: 88-102, 2017 05.
Article in English | MEDLINE | ID: mdl-28384482

ABSTRACT

Multiple levels of representation are involved in reading single words: visual representations of letter shape, orthographic representations of letter identity and order, phonological representations of the word's pronunciation, and semantic representations of its meaning. Previous lesion and neuroimaging studies have identified a network of regions recruited during word reading, including ventral occipital-temporal regions and the angular gyrus (AG). However, there is still debate about what information is being represented and processed in these regions. This study has two aims. The first is to help adjudicate between competing hypotheses concerning the role of ventral occipital cortex in reading. The second is to adjudicate between competing hypotheses concerning the role of the AG in reading. Participants read words in the scanner while performing a proper name detection task and we use a multivariate pattern analysis technique for analyzing fMRI data - representational similarity analysis (RSA) - to decode the type of information being represented in these regions based on computationally explicit theories. Distributed patterns of activation in the left ventral occipitotemporal cortex (vOT) and the AG show evidence of some type of orthographic processing, while the right hemisphere homologues of the vOT supports visual, but not orthographic, information processing of letter strings. In addition, there is evidence of left-lateralized semantic processing in the lvOT and evidence of top-down feedback in the lvOT. Taken together, these results suggest an interactive activation theory of visual word processing in which both the lvOT and lAG are neural loci of an orthographic level of representations.


Subject(s)
Brain Mapping , Pattern Recognition, Visual/physiology , Reading , Temporal Lobe/physiology , Adolescent , Adult , Female , Functional Laterality/physiology , Humans , Image Processing, Computer-Assisted/methods , Male , Occipital Lobe/physiology , Photic Stimulation/methods , Young Adult
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