Publications by authors named "Abegg A"

Studying synapses in vivo presents challenges due to the complexity of accurately targeting and visualizing specific synaptic proteins within the brain. Here, we present a protocol for in vivo analysis of pre- and post-synaptic protein function in mice. We describe steps for combining adeno-associated virus (AAV)-mediated gene transfer to manipulate specific neuron subtypes.

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The precise function of specialized GABAergic interneuron subtypes is required to provide appropriate synaptic inhibition for regulating principal neuron excitability and synchronization within brain circuits. Of these, parvalbumin-type (PV neuron) dysfunction is a feature of several sex-biased psychiatric and brain disorders, although, the underlying developmental mechanisms are unclear. While the transcriptional action of sex hormones generates sexual dimorphism during brain development, whether kinase signaling contributes to sex differences in PV neuron function remains unexplored.

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Gephyrin is the main scaffolding protein at inhibitory postsynaptic sites, and its clusters are the signaling hubs where several molecular pathways converge. Post-translational modifications (PTMs) of gephyrin alter GABA receptor clustering at the synapse, but it is unclear how this affects neuronal activity at the circuit level. We assessed the contribution of gephyrin PTMs to microcircuit activity in the mouse barrel cortex by slice electrophysiology and in vivo two-photon calcium imaging of layer 2/3 (L2/3) pyramidal cells during single-whisker stimulation.

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In the past two decades, health care has become a global market and transnational practice. An emerging body of literature examines the astounding variety of drivers, conditions, and experiences. However, the question of how traveling abroad for treatment emerges as an option and takes shape in people's illness trajectories has gained little attention thus far.

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Article Synopsis
  • The development of precise episodic memories in children happens with age, starting from less detailed gist-like memories in younger kids.
  • Research in mice shows that immature hippocampal cells can't form these specific memories due to a lack of competitive neuronal processes until they reach about four weeks old.
  • The maturation of certain interneurons and their supportive networks in the hippocampus is crucial for transforming vague memories into precise ones, enabling better memory formation.
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Studying species interactions in nature often requires elaborated logistics and intense fieldwork. The difficulties in such task might hinder our ability to answer questions on how biotic interactions change with the environment. Fortunately, a workaround to this problem lies within scientific collections.

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The secretive behavior and life history of snakes makes studying their biology, distribution, and the epidemiology of venomous snakebite challenging. One of the most useful, most versatile, and easiest to collect types of biological data are photographs, particularly those that are connected with geographic location and date-time metadata. Photos verify occurrence records, provide data on phenotypes and ecology, and are often used to illustrate new species descriptions, field guides and identification keys, as well as in training humans and computer vision algorithms to identify snakes.

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Neural stem cells (NSCs) generate neurons and glial cells throughout embryonic and postnatal brain development. The role of S-palmitoylation (also referred to as S-acylation), a reversible posttranslational lipid modification of proteins, in regulating the fate and activity of NSCs remains largely unknown. We used an unbiased screening approach to identify proteins that are S-acylated in mouse NSCs and showed that bone morphogenic protein receptor 1a (BMPR1a), a core mediator of BMP signaling, is palmitoylated.

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The norms regarding validity and formulation of specific epithets in Zoology are ruled by the International Code of Zoological Nomenclature (ICZN 1999), a published convention of the International Commission on Zoological Nomenclature, that operates under a vast array of underlying nomenclatural principles. One of its components is Article 31, which rules upon the formation of specific or subspecific epithets for personal names, by the use of nomina (sensu Dubois 2007) under genitive case. As discussed by Dubois (2007), this has erroneously led several authors to assume that the aforementioned nomina should exclusively end in "-i" if dedicated to a man (or -orum, for plural), and in "-ae" if dedicated to a woman (or -arum, for plural) (being also important to state that this provision is sensitive on whether the chosen nomina is a modern personal name (Art.

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We recorded a second specimen of the poorly known insular blind snake Liotyphlops caissara. This new specimen expands the morphological variation of the number of dorsal scales in the genus Liotyphlops to 296 (vs. 304 in L.

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The Serra da Mantiqueira is one of the least inventoried physiographic areas of southeastern Brazil. There is great potential for detection of endemic species for which little or nothing is known about basic aspects of natural history. The Parque Estadual da Serra do Papagaio (PESP) within the Serra da Mantiqueira is an area of extreme biological importance because it houses mixed formations of grasslands, ombrophilous forests, and enclaves of Araucaria forests (mixed ombrophilous forest).

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The Troschel's Pampas Snake, Phimophis guianensis (Troschel, 1848), is widely distributed in Amazonian Savannas at northern South America and a small portion of southern Central America, being recorded to Brazil based on three historical records, that ranged from 1997 to 2002, in Amapá and Pará states. In this study, we revise all known records of P. guianensis, providing an updated distribution map, and the first record to Roraima state.

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A central problem in evolutionary theory concerns the mechanisms by which adaptations requiring multiple mutations emerge in natural populations. We develop a series of expressions that clarify the scaling of the time to establishment of complex adaptations with population size, mutation rate, magnitude of the selective disadvantage of intermediate-state alleles, and the complexity of the adaptation. In general, even in the face of deleterious intermediate steps, the time to establishment is minimized in populations with very large size.

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Here we describe a post-translational modification of SC-63032, a variant of the species restricted, multi-lineage hematopoeitic factor human interleukin-3 (hIL-3). We have made two new dendritic polymer (polyamidoamine or PAMAM dendrimers, generation 5)-SC-63032 bioconjugates. Using two distinct chemistries (one of which is novel to this work), we achieved site-specific conjugation with respect to the amino acid in the proteins ligated to the dendrimers.

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There have been a number of reports suggesting inhibition of prostaglandin production may impact tumor-mediated wasting and levels of associated humoral factors such as hypercalcemia. These reductions were achieved using traditional nonsteroidal anti-inflammatory drugs (NSAIDs), which are often contraindicated in cancer patients. This is especially true during chemotherapeutic regimens due to concerns of bleeding from gastrointestinal and hematopoietic toxicities associated with inhibition of the housekeeping cyclooxygenase enzyme COX-1.

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The in vitro activity of leridistim was characterized for cell proliferation, generation of colony-forming units (CFU) and differentiation of CD34+ cells. In AML-193.1.

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Objective: The signaling pathways induced by promegapoietin (PMP), a family of chimeric growth factors that activate the human IL-3 and c-Mpl receptors, were investigated.

Methods: The biological activity of PMP was examined by receptor binding, cell proliferation, ex vivo expansion of hematopoietic progenitor cells, and in vivo production of platelets. The activation of signaling pathways was examined by Western blot and Northern blot analyses.

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Myelopoietins comprise a class of chimeric cytokine receptor agonists consisting of an hIL-3 (human interleukin-3) receptor agonist and an hG-CSF (human granulocyte colony-stimulating factor) receptor agonist linked head-to-tail at their respective carboxy and amino termini. The combination of an early acting cytokine (hIL-3) with a late acting one (hG-CSF) allows efficient hematopoeitic reconstruction following myeloablative insult, and drives differentiation of non-myelocytic lineages (ie thrombocytic lineages) that are inaccessible using hG-CSF alone, in both preclinical models and clinical settings. A myelopoietin species was displayed and mutagenized on filamentous bacteriophage: both component agonists of myelopoietin were presented in biologically functional conformations as each recognized its corresponding receptor.

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Myelopoietins (MPOs) are a family of engineered dual interleukin-3 (IL-3) and granulocyte colony-stimulating factor (G-CSF) receptor agonists that are superior in comparison to the single agonists in their ability to promote the growth and maturation of hematopoietic cells of the myeloid lineage. A series of MPO molecules were created which incorporated circularly permuted G-CSF (cpG-CSF) sequences with an IL-3 receptor (IL-3R) agonist moiety attached at locations that correspond to the loops that connect the helices of the G-CSF four-helix bundle structure. The cpG-CSF linkage sites (using the original sequence numbering) were residue 39, which is at the beginning of the first loop connecting helices 1 and 2; residue 97, which is in the turn connecting helices 2 and 3; and residues 126, 133, and 142, which are at the beginning, middle, and end, respectively, of the loop connecting helices 3 and 4.

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The sequence of granulocyte colony-stimulating factor (G-CSF) has been circularly permuted by introducing new chain termini into interhelical loops and by constraining the N- and C-terminal helices, either by direct linkage of the termini (L0) or by substitution of the amino-terminal 10-residue segment with a seven-residue linker composed of glycines and serines (L1). All the circularly permuted G-CSFs (cpG-CSFs) were able to fold into biologically active structures that could recognize the G-CSF receptor. CD and NMR spectroscopy demonstrated that all of the cpG-CSFs adopted a fold similar to that of the native molecule, except for one [cpG-CSF(L1)[142/141]] which has the new termini at the end of loop 34 with the shorter L1 linker.

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A deletion derivative of the cytokine human interleukin-3 (hIL-3(15-125), comprising amino acids 15-125 of the native protein) was produced as a fusion to the filamentous phage surface protein pIII. The cytokine was detected in association with phage particles by protein immunoblotting. Compared to an equivalent quantity of soluble-cytokine, phage-presented hIL-3(15-125) exhibited reduced biological activity in a hIL-3-dependent cell proliferation assay.

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Interleukin-3 (IL-3) is a cytokine that stimulates the proliferation and differentiation of hematopoietic cells. The hyperactive hIL-3 variant SC-55494 was shown to have at least two major conformations by high-resolution NMR spectroscopy. Mutants of SC-55494 were constructed in which alanine was substituted for proline in order to test the hypothesis that proline cis-trans isomerization is the source of the observed conformational heterogeneity, as well as to evaluate the effect of prolyl peptide bond configuration on biological activity.

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The behavioral disturbances of 16 nursing home patients with a history of sundowning behaviour and dementia were treated with light therapy instead of psychopharmacological medication. After the withdrawal of the before established medication a very individual, heterogenous deterioration of the symptoms was noted. A significant improvement of the behaviour was not found by light therapy in any patient.

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Lymphoid cells from most inbred mouse strains respond to amphotericin B (AmB)-induced immunostimulation. However, C57BL/6 mice and related strains display low or absent lymphoid cell stimulation by AmB and enhanced susceptibility to AmB toxicity. Experiments reported here show that in vitro incubation with AmB can stimulate AKR (AmB-high responder strain) macrophage proliferation.

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