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1.
Glycobiology ; 34(1)2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-37944064

RESUMO

During the COVID-19 outbreak, numerous tools including protein-based vaccines have been developed. The methylotrophic yeast Pichia pastoris (synonymous to Komagataella phaffii) is an eukaryotic cost-effective and scalable system for recombinant protein production, with the advantages of an efficient secretion system and the protein folding assistance of the secretory pathway of eukaryotic cells. In a previous work, we compared the expression of SARS-CoV-2 Spike Receptor Binding Domain in P. pastoris with that in human cells. Although the size and glycosylation pattern was different between them, their protein structural and conformational features were indistinguishable. Nevertheless, since high mannose glycan extensions in proteins expressed by yeast may be the cause of a nonspecific immune recognition, we deglycosylated RBD in native conditions. This resulted in a highly pure, homogenous, properly folded and monomeric stable protein. This was confirmed by circular dichroism and tryptophan fluorescence spectra and by SEC-HPLC, which were similar to those of RBD proteins produced in yeast or human cells. Deglycosylated RBD was obtained at high yields in a single step, and it was efficient in distinguishing between SARS-CoV-2-negative and positive sera from patients. Moreover, when the deglycosylated variant was used as an immunogen, it elicited a humoral immune response ten times greater than the glycosylated form, producing antibodies with enhanced neutralizing power and eliciting a more robust cellular response. The proposed approach may be used to produce at a low cost, many antigens that require glycosylation to fold and express, but do not require glycans for recognition purposes.


Assuntos
COVID-19 , Saccharomycetales , Vacinas , Humanos , COVID-19/diagnóstico , COVID-19/prevenção & controle , Teste para COVID-19 , Pichia/genética , Pichia/metabolismo , SARS-CoV-2/genética , SARS-CoV-2/metabolismo , Proteínas Recombinantes/química , Vacinas/metabolismo , Anticorpos Neutralizantes/metabolismo , Anticorpos Antivirais
2.
Agora USB ; 23(2): 671-683, jul.-dic. 2023. tab
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1573785

RESUMO

Resumen: El propósito de este artículo es compartir la discusión sobre el papel fundamental de los elementos constitutivos de la voz en los procesos de diagnóstico y propues tas terapéuticas relacionadas con el TEA. Elementos encontrados en el estudio "Desarrollo de protocolo clínico para el diagnóstico temprano del autismo" (Villalobos y Pacca, 2020). Los casos, Vera y Saul, se retoman para ilustrar el lugar que tiene la voz y la palabra en el desarrollo intersubjetivo. A partir de estos casos se eviden cian los alcances y limitaciones que tienen algunas pruebas para el diagnóstico del TEA al momento de evaluar indicadores comunicativos. Dado que la voz y la palabra llevan la impronta de la subjetividad de cada persona, considerar su análi sis se hace relevante en el diagnóstico comprensivo de TEA, pues complementa la observación diagnóstica propuesta desde las principales pruebas mundialmente reconocidas para esta problemática del desarrollo, como por ejemplo ADOS-2.


Abstract: The purpose of this article is to share the discussion on the fundamental role of the constitutive elements of the voice in the diagnostic processes and thera peutic proposals related to ASD. Elements found in the study "Development of clinical protocol for early diagnosis of autism" (Villalobos & Pacca, 2021). The cases, Vera & Saul, are taken up again to illustrate the place of voice and speech in intersubjective development. From these cases, the scope and limitations of some tests for the diagnosis of ASD when evaluating communicative indicators become evident. Given that voice and speech bear the imprint of each person's subjectivity, considering their analysis becomes relevant in the comprehensive diagnosis of ASD, as it complements the diagnostic observation proposed by the main tests worldwide recognized for this developmental problem, such as -ADOS-2- Autism Diagnostic Observation Scale-2.

3.
Mycorrhiza ; 33(5-6): 425-447, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37792114

RESUMO

Core Ericaceae produce delicate hair roots with inflated rhizodermal cells that host plethora of fungal symbionts. These poorly known mycobionts include various endophytes, parasites, saprobes, and the ericoid mycorrhizal (ErM) fungi (ErMF) that form the ErM symbiosis crucial for the fitness of their hosts. Using microscopy and high-throughput sequencing, we investigated their structural and molecular diversity in 14 different host × site combinations in Northern Bohemia (Central Europe) and Argentine Patagonia (South America). While we found typical ericoid mycorrhiza in all combinations, we did not detect ectomycorrhiza and arbuscular mycorrhiza. Superficial mantles of various thickness formed by non-clamped hyphae were observed in all combinations except Calluna vulgaris from N. Bohemia. Some samples contained frequent intercellular hyphae while others possessed previously unreported intracellular haustoria-like structures linked with intracellular hyphal coils. The 711 detected fungal OTU were dominated by Ascomycota (563) and Basidiomycota (119), followed by four other phyla. Ascomycetes comprised Helotiales (255), Pleosporales (53), Chaetothyriales (42), and other 19 orders, while basidiomycetes Sebacinales (42), Agaricales (28), Auriculariales (7), and other 14 orders. While many dominant OTU from both hemispheres lacked close relatives in reference databases, many were very similar to identical to unnamed sequences from around the world. On the other hand, several significant ericaceous mycobionts were absent in our dataset, incl. Cairneyella, Gamarada, Kurtia, Lachnum, and Leohumicola. Most of the detected OTU could not be reliably linked to a particular trophic mode, and only two could be reliably assigned to the archetypal ErMF Hyaloscypha hepaticicola. Probable ErMF comprised Hyaloscypha variabilis and Oidiodendron maius, both detected only in N. Bohemia. Possible ErMF comprised sebacinoid fungi and several unnamed members of Hyaloscypha s. str. While H. hepaticicola was dominant only in C. vulgaris, this model ErM host lacked O. maius and sebacinoid mycobionts. Hyaloscypha hepaticicola was absent in two and very rare in six combinations from Patagonia. Nine OTU represented dark septate endophytes from the Phialocephala fortinii s. lat.-Acephala applanata species complex, including the most abundant OTU (the only detected in all combinations). Statistical analyses revealed marked differences between N. Bohemia and Patagonia, but also within Patagonia, due to the unique community detected in a Valdivian temperate rainforest. Our results show that the ericaceous hair roots may host diverse mycobionts with mostly unknown functions and indicate that many novel ErMF lineages await discovery. Transhemispheric differences (thousands of km) in their communities may be evenly matched by local differences (scales of km, m, and less).


Assuntos
Basidiomycota , Ericaceae , Micorrizas , Micorrizas/genética , Ericaceae/microbiologia , Raízes de Plantas/microbiologia , Simbiose , Endófitos/genética
4.
Neuropharmacology ; 239: 109674, 2023 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-37541383

RESUMO

The molecular processes that underlie long-term memory formation involve signaling pathway activation by neurotransmitter release, which induces the expression of immediate early genes, such as Zif268, having a key role in memory formation. In this work, we show that the cannabinoid CB1 receptor signaling is necessary for the effects of dexamethasone on the behavioral response in an inhibitory avoidance task, on dexamethasone-induced ERK phosphorylation, and on dexamethasone-dependent Zif268 expression. Furthermore, we provide primary evidence for the mechanism responsible for this crosstalk between cannabinoid and glucocorticoid-mediated signaling pathways, showing that dexamethasone regulates endocannabinoid metabolism by inhibiting the activity of the Fatty acid amide hydrolase (FAAH), an integral membrane enzyme that hydrolyzes endocannabinoids and related amidated signaling lipids. Our results provide novel evidence regarding the role of the endocannabinoid system, and in particular of the CB1 receptor, as a mediator of the effects of glucocorticoids on the consolidation of aversive memories.


Assuntos
Canabinoides , Consolidação da Memória , Endocanabinoides/metabolismo , Receptor CB1 de Canabinoide/genética , Canabinoides/farmacologia , Transdução de Sinais , Glucocorticoides/farmacologia , Dexametasona/farmacologia , Amidoidrolases , Moduladores de Receptores de Canabinoides/farmacologia
5.
Cells ; 12(3)2023 01 29.
Artigo em Inglês | MEDLINE | ID: mdl-36766786

RESUMO

Triple negative breast cancer (TNBC) is an aggressive breast cancer subtype for which no effective targeted therapies are available. Growing evidence suggests that chemotherapy-resistant cancer cells with stem-like properties (CSC) may repopulate the tumor. The androgen receptor (AR) is expressed in up to 50% of TNBCs, and AR inhibition decreases CSC and tumor initiation. Runt-related transcription factor 1 (RUNX1) correlates with poor prognosis in TNBC and is regulated by the AR in prostate cancer. Our group has shown that RUNX1 promotes TNBC cell migration and regulates tumor gene expression. We hypothesized that RUNX1 is regulated by the AR and that both may work together in TNBC CSC to promote disease recurrence following chemotherapy. Chromatin immunoprecipitation sequencing (ChIP-seq) experiments in MDA-MB-453 revealed AR binding to RUNX1 regulatory regions. RUNX1 expression is upregulated by dihydrotestosterone (DHT) in MDA-MB-453 and in an AR+-TNBC HCI-009 patient-derived xenograft (PDX) tumors (p < 0.05). RUNX1 is increased in a CSC-like experimental model in MDA-MB-453 and SUM-159PT cells (p < 0.05). Inhibition of RUNX1 transcriptional activity reduced the expression of CSC markers. Interestingly, RUNX1 inhibition reduced cell viability and enhanced paclitaxel and enzalutamide sensitivity. Targeting RUNX1 may be an attractive strategy to potentiate the anti-tumor effects of AR inhibition, specifically in the slow-growing CSC-like populations that resist chemotherapy which lead to metastatic disease.


Assuntos
Neoplasias de Mama Triplo Negativas , Humanos , Linhagem Celular Tumoral , Subunidade alfa 2 de Fator de Ligação ao Core/genética , Recidiva Local de Neoplasia , Receptores Androgênicos/metabolismo , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Neoplasias de Mama Triplo Negativas/genética , Neoplasias de Mama Triplo Negativas/patologia , Feminino
6.
Biotechnol Bioeng ; 120(2): 409-425, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36225115

RESUMO

Frataxin is a kinetic activator of the mitochondrial supercomplex for iron-sulfur cluster assembly. Low frataxin expression or a decrease in its functionality results in Friedreich's Ataxia (FRDA). With the aim of creating new molecular tools to study this metabolic pathway, and ultimately, to explore new therapeutic strategies, we have investigated the possibility of obtaining small proteins exhibiting a high affinity for frataxin. In this study, we applied the ribosome display approach, using human frataxin as the target. We focused on Affi_224, one of the proteins that we were able to select after five rounds of selection. We have studied the interaction between both proteins and discussed some applications of this specific molecular tutor, concerning the modulation of the supercomplex activity. Affi_224 and frataxin showed a KD value in the nanomolar range, as judged by surface plasmon resonance analysis. Most likely, it binds to the frataxin acidic ridge, as suggested by the analysis of chemical shift perturbations (nuclear magnetic resonance) and computational simulations. Affi_224 was able to increase Cys NFS1 desulfurase activation exerted by the FRDA frataxin variant G130V. Importantly, Affi_224 interacts with frataxin in a human cellular model. Our results suggest quaternary addition may be a new tool to modulate frataxin function in vivo. Nevertheless, more functional experiments under physiological conditions should be carried out to evaluate Affi_224 effectiveness in FRDA cell models.


Assuntos
Liases de Carbono-Enxofre , Proteínas de Ligação ao Ferro , Humanos , Proteínas de Ligação ao Ferro/genética , Proteínas de Ligação ao Ferro/química , Proteínas de Ligação ao Ferro/metabolismo , Liases de Carbono-Enxofre/química , Liases de Carbono-Enxofre/metabolismo , Frataxina
8.
Front Plant Sci ; 13: 873204, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35755655

RESUMO

Arbuscular mycorrhiza (AM) and ectomycorrhiza (EcM) are the most abundant and widespread types of mycorrhizal symbiosis, but there is little and sometimes conflicting information regarding the interaction between AM fungi (AMF) and EcM fungi (EcMF) in soils. Their competition for resources can be particularly relevant in successional ecosystems, which usually present a transition from AM-forming herbaceous vegetation to EcM-forming woody species. The aims of this study were to describe the interaction between mycorrhizal fungal communities associated with AM and EcM hosts naturally coexisting during primary succession on spoil banks and to evaluate how this interaction affects growth and mycorrhizal colonization of seedlings of both species. We conducted a greenhouse microcosm experiment with Betula pendula and Hieracium caespitosum as EcM and AM hosts, respectively. They were cultivated in three-compartment rhizoboxes. Two lateral compartments contained different combinations of both host plants as sources of fungal mycelia colonizing the middle compartment, where fungal biomass, diversity, and community composition as well as the growth of each host plant species' seedlings were analyzed. The study's main finding was an asymmetric outcome of the interaction between the two plant species: while H. caespitosum and associated AMF reduced the abundance of EcMF in soil, modified the composition of EcMF communities, and also tended to decrease growth and mycorrhizal colonization of B. pendula seedlings, the EcM host did not have such effects on AM plants and associated AMF. In the context of primary succession, these findings suggest that ruderal AM hosts could hinder the development of EcM tree seedlings, thus slowing the transition from AM-dominated to EcM-dominated vegetation in early successional stages.

9.
Pharmacol Res Perspect ; 10(2): e00913, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35184416

RESUMO

G protein-coupled receptors kinase 2 (GRK2) plays a major role in receptor regulation and, as a consequence, in cell biology and physiology. GRK2-mediated receptor desensitization is performed by its kinase domain, which exerts receptor phosphorylation promoting G protein uncoupling and the cessation of signaling, and by its RGS homology (RH) domain, able to interrupt G protein signaling. Since GRK2 activity is exacerbated in several pathologies, many efforts to develop inhibitors have been conducted. Most of them were directed toward GRK2 kinase activity and showed encouraging results on in vitro systems and animal models. Nevertheless, limitations including unspecific effects or pharmacokinetics issues prevented them from advancing to clinical trials. Surprisingly, even though the RH domain demonstrated the ability to desensitize GPCRs, this domain has been less explored. Herein, we show in vitro activity of a series of compounds that, by inhibiting GRK2 RH domain, increase receptor cAMP response, avoid GRK2 translocation to the plasma membrane, inhibit coimmunoprecipitation of GRK2 with Gαs subunit of heterotrimeric G protein, and prevent receptor desensitization. Also, we preliminarily evaluated candidates' ADMET properties and observed suitable lipophilicity and cytotoxicity. These novel inhibitors of phosphorylation-independent actions of GRK2 might be useful in elucidating other RH domain roles and lay the foundation for the development of innovative pharmacologic therapy for diseases where GRK2 activity is exacerbated.


Assuntos
AMP Cíclico/metabolismo , Quinase 2 de Receptor Acoplado a Proteína G/antagonistas & inibidores , Linhagem Celular Tumoral , Desenvolvimento de Medicamentos , Quinase 2 de Receptor Acoplado a Proteína G/metabolismo , Células HEK293 , Humanos , Fosforilação , Domínios Proteicos/efeitos dos fármacos , Proteínas RGS/metabolismo , Transdução de Sinais/efeitos dos fármacos
10.
Sci Educ (Dordr) ; 31(6): 1429-1448, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34703080

RESUMO

Scientific research is a human endeavour, performed by communities of people. Disproportionate focus on only some of the features related to this obvious fact has been used to discredit the reliability of scientific knowledge and to relativize its value when compared with knowledge stemming from other sources. This epistemic relativism is widespread nowadays and is arguably dangerous for our collective future, as the threat of climate change and its denialism clearly shows. In this work, we argue that even though the social character of science is indeed real, it does not entail epistemic relativism with respect to scientific knowledge, but quite the opposite, as there are several characteristic behaviours of this specific human community that were built to increase the reliability of scientific outputs. Crucially, we believe that present-day scientific education is lacking in the description and analysis of these particularities of the scientific community as a social group and that further investing in this area could greatly improve the possibilities of critical analysis of the often very technical issues that the citizens and future citizens of our modern societies have to confront.

11.
Cells ; 10(11)2021 11 05.
Artigo em Inglês | MEDLINE | ID: mdl-34831249

RESUMO

Antihistamines and glucocorticoids (GCs) are often used together in the clinic to treat several inflammation-related situations. Although there is no rationale for this association, clinical practice has assumed that, due to their concomitant anti-inflammatory effects, there should be an intrinsic benefit to their co-administration. In this work, we evaluated the effects of the co-treatment of several antihistamines on dexamethasone-induced glucocorticoid receptor transcriptional activity on the expression of various inflammation-related genes in A549 and U937 cell lines. Our results show that all antihistamines potentiate GCs' anti-inflammatory effects, presenting ligand-, cell- and gene-dependent effects. Given that treatment with GCs has strong adverse effects, particularly on bone metabolism, we also examined the impact of antihistamine co-treatment on the expression of bone metabolism markers. Using MC3T3-E1 pre-osteoblastic cells, we observed that, though the antihistamine azelastine reduces the expression of dexamethasone-induced bone loss molecular markers, it potentiates osteoblast apoptosis. Our results suggest that the synergistic effect could contribute to reducing GC clinical doses, ineffective by itself but effective in combination with an antihistamine. This could result in a therapeutic advantage, as the addition of an antihistamine may reinforce the wanted effects of GCs, while related adverse effects could be diminished or at least mitigated. By modulating the patterns of gene activation/repression mediated by GR, antihistamines could enhance only the desired effects of GCs, allowing their effective dose to be reduced. Further research is needed to correctly determine the clinical scope, benefits, and potential risks of this therapeutic strategy.


Assuntos
Anti-Inflamatórios/farmacologia , Dexametasona/farmacologia , Regulação da Expressão Gênica , Antagonistas dos Receptores Histamínicos/farmacologia , Inflamação/genética , Receptores de Glucocorticoides/metabolismo , Animais , Biomarcadores/metabolismo , Osso e Ossos/efeitos dos fármacos , Osso e Ossos/metabolismo , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Genes Reporter , Humanos , Camundongos , NF-kappa B/metabolismo , Osteoblastos/efeitos dos fármacos , Osteoblastos/metabolismo , Ftalazinas/farmacologia , Fator de Necrose Tumoral alfa/farmacologia
12.
J Sci Food Agric ; 101(12): 5082-5088, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33570749

RESUMO

BACKGROUND: Kiwifruit is an important horticultural crop all over the world and its development is important in Argentina. This dioecious crop has a short blooming period with nectarless flowers, and its fruit production depends on cross-pollination. Here, we tested whether kiwifruit quality increases by using honeybees exposed to female flowers treated with an artificial fragrance. The three experimental treatments were: A, sprinkled female flowers with 1:1 sugar syrup + Lavandula hybrida extract solution (a new attractant substance especially developed for this study named Lavandin Grosso); B, sprinkled female flowers with 1:1 water + sugar syrup (female flowers with additional sugar syrup reward); C (control; female flowers exposed to honeybees). RESULTS: The results showed a higher number of visits of honeybees to the female flowers sprinkled with the attractant substance, Lavandin Grosso, as well as higher fruit quality (weight, number of seeds, regularity in fruit size). CONCLUSION: Our study demonstrates the potential of fragrance-treated flowers to improve yield production in kiwifruit. © 2021 Society of Chemical Industry.


Assuntos
Actinidia/parasitologia , Abelhas/fisiologia , Frutas/química , Odorantes/análise , Actinidia/química , Actinidia/crescimento & desenvolvimento , Animais , Argentina , Flores/crescimento & desenvolvimento , Flores/parasitologia , Frutas/crescimento & desenvolvimento , Frutas/parasitologia , Polinização , Controle de Qualidade
13.
Eur J Pharmacol ; 896: 173913, 2021 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-33508282

RESUMO

Histamine H1 receptor ligands used clinically as antiallergics rank among the most widely prescribed and over-the-counter drugs in the world. They exert the therapeutic actions by blocking the effects of histamine, due to null or negative efficacy towards Gαq-phospholipase C (PLC)-inositol triphosphates (IP3)-Ca2+ and nuclear factor-kappa B cascades. However, there is no information regarding their ability to modulate other receptor responses. The aim of the present study was to investigate whether histamine H1 receptor ligands could display positive efficacy concerning receptor desensitization, internalization, signaling through Gαq independent pathways or even transcriptional regulation of proinflammatory genes. While diphenhydramine, triprolidine and chlorpheniramine activate ERK1/2 (extracellular signal-regulated kinase 1/2) pathway in A549 cells, pre-treatment with chlorpheniramine or triprolidine completely desensitize histamine H1 receptor mediated Ca2+ response, and both diphenhydramine and triprolidine lead to receptor internalization. Unlike histamine, histamine H1 receptor desensitization and internalization induced by antihistamines prove to be independent of G protein-coupled receptor kinase 2 (GRK2) phosphorylation. Also, unlike the reference agonist, the recovery of the number of cell-surface histamine H1 receptors is a consequence of de novo synthesis. On the other hand, all of the ligands lack efficacy regarding cyclooxygenase-2 (COX-2) and interleukin-8 (IL-8) mRNA regulation. However, a prolonged exposure with each of the antihistamines impaires the increase in COX-2 and IL-8 mRNA levels induced by histamine, even after ligand removal. Altogether, these findings demonstrate the biased nature of histamine H1 receptor ligands contributing to a more accurate classification, and providing evidence for a more rational and safe use of them.


Assuntos
MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Agonistas dos Receptores Histamínicos/farmacologia , Antagonistas dos Receptores Histamínicos H1/farmacologia , Receptores Histamínicos H1/efeitos dos fármacos , Células A549 , Sinalização do Cálcio/efeitos dos fármacos , Ciclo-Oxigenase 2/genética , Ciclo-Oxigenase 2/metabolismo , Agonismo Inverso de Drogas , Ativação Enzimática , Quinase 2 de Receptor Acoplado a Proteína G/genética , Quinase 2 de Receptor Acoplado a Proteína G/metabolismo , Subunidades alfa Gq-G11 de Proteínas de Ligação ao GTP/metabolismo , Humanos , Mediadores da Inflamação/metabolismo , Inositol 1,4,5-Trifosfato/metabolismo , Interleucina-8/genética , Interleucina-8/metabolismo , Ligantes , Fosforilação , Transporte Proteico , Receptores Histamínicos H1/metabolismo , Fosfolipases Tipo C/metabolismo
14.
Transfus Apher Sci ; 60(2): 103046, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33455879

RESUMO

The recurrence of primary focal segmental glomerulosclerosis (FSGS) after kidney transplantation (KT) appears in 30 % of the recipients. Sometimes it can cause the loss of the allograft. Although many treatments for this condition have been reported, 20 %-40 % of the affected patients are refractory or presents frequents relapses. In this paper we describe the evolution of three recipients treated with long-term plasmapheresis therapy after a recurrence of FSGS with a bad or incomplete response to other treatments. Although our findings require confirmation, long-term plasmapheresis could be a therapeutic option for this condition.


Assuntos
Glomerulosclerose Segmentar e Focal/terapia , Transplante de Rim/efeitos adversos , Plasmaferese/métodos , Adulto , Feminino , Humanos , Transplante de Rim/métodos , Masculino , Pessoa de Meia-Idade , Recidiva , Resultado do Tratamento
15.
FEBS J ; 288(1): 229-243, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32333821

RESUMO

Intracellular cAMP (i-cAMP) levels play an important role in acute myeloid leukemia (AML) cell proliferation and differentiation. Its levels are the result of cAMP production, degradation, and exclusion. We have previously described histamine H2 receptors and MRP4/ABCC4 as two potential targets for AML therapy. Acting through histamine H2 receptors, histamine increases cAMP production/synthesis, while MRP4/ABCC4 is responsible for the exclusion of this cyclic nucleotide. In this study, we show that histamine treatment induces MRP4/ABCC4 expression, augmenting cAMP efflux, and that histamine, in combination with MRP inhibitors, is able to reduce AML cell proliferation. Histamine, through histamine H2 receptor, increases i-cAMP levels and induces MRP4 transcript and protein levels in U937, KG1a, and HL-60 cells. Moreover, histamine induces MRP4 promoter activity in HEK293T cells transfected with histamine H2 receptor (HEK293T-H2 R). Our results support that the cAMP/Epac-PKA pathway, and not MEK/ERK nor PI3K/AKT signaling cascades, is involved in histamine-mediated upregulation of MRP4 levels. Finally, the addition of histamine potentiates the inhibition of U937, KG1a, and HL-60 cell proliferation induced by MRP4 inhibitors. Our data highlight that the use of a poly-pharmacological approach aimed at different molecular targets would be beneficial in AML treatment.


Assuntos
Proteínas Quinases Dependentes de AMP Cíclico/genética , AMP Cíclico/metabolismo , Fatores de Troca do Nucleotídeo Guanina/genética , Histamina/farmacologia , Proteínas Associadas à Resistência a Múltiplos Medicamentos/genética , Receptores Histamínicos H2/genética , Benzotiazóis/farmacologia , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Regulação Leucêmica da Expressão Gênica , Genes Reporter , Fatores de Troca do Nucleotídeo Guanina/metabolismo , Células HEK293 , Células HL-60 , Histamina/metabolismo , Humanos , Luciferases/genética , Luciferases/metabolismo , Terapia de Alvo Molecular/métodos , Proteínas Associadas à Resistência a Múltiplos Medicamentos/antagonistas & inibidores , Proteínas Associadas à Resistência a Múltiplos Medicamentos/metabolismo , Probenecid/farmacologia , Regiões Promotoras Genéticas , Propionatos/farmacologia , Quinolinas/farmacologia , Receptores Histamínicos H2/metabolismo , Transdução de Sinais , Triazóis/farmacologia , Células U937
16.
Rev Argent Microbiol ; 53(2): 98-103, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33176954

RESUMO

The aim of this study was to estimate the diversity and prevalence of both groups of Brucella canis 1 and 2 with and without deletion respectively in different areas of Argentina. A total of 104 bacterial cultures were typed as B. canis strains using the classical biotyping method. Two PCR assays were performed to confirm that all isolates were B. canis and not Brucella suis. The differentiation between groups 1 and 2 was achieved using another PCR assay and the diversity of B. canis isolates was assessed with four MLVA_16 markers. All strains belonged to Group 2. Bruce 09 marker (MLVA_16 assay) showed the greatest diversity. Only Group 2 of B. canis was identified among the strains evaluated. The markers chosen from the MLVA_16 allowed us to detect genetic diversity among the strains of B. canis studied.


Assuntos
Brucella canis , Brucella suis , Brucelose , Argentina/epidemiologia , Brucella canis/genética , Brucelose/epidemiologia , Brucelose/veterinária , Humanos , Reação em Cadeia da Polimerase
17.
Rev. latinoam. cienc. soc. niñez juv ; 18(2): 169-198, jul.-dic. 2020. tab
Artigo em Espanhol | LILACS | ID: biblio-1144717

RESUMO

Resumen (analítico) El artículo analiza las construcciones de juventud presentes en la Acción Católica Argentina y sus vínculos con trayectorias de jóvenes militantes insertos en parroquias del Gran Buenos Aires. Para el abordaje metodológico cualitativo se utilizan los siguientes materiales de campo, producidos entre 2016 y 2018: entrevistas en profundidad realizadas a jóvenes católicos, registros de observación participante en parroquias y eventos nacionales de Acción Católica Argentina y análisis de documentos institucionales. Dentro de la Acción Católica Argentina, se identifican tensiones entre las definiciones de juventud producidas por la institución y las trayectorias juveniles. Los jóvenes experimentan modos de «ser¼ y de «vivir¼ la juventud distintos a los propuestos por la Acción Católica Argentina, acordes con los cambios sociales y culturales que se produjeron en Argentina en las últimas décadas.


Abstract (analytical) This article analyzes the constructions of youth produced in the Acción Católica Argentina (Argentinian Catholic Action) organization and their link with the trajectories of militant youth living in parishes of Gran Buenos Aires. Field materials produced between 2016 and 2018 are analyzed using a qualitative methodological approach that consists of: in-depth interviews with Catholic youth; participant observation records from parish and national Argentinian Catholic Action events; and the analysis of institutional documents. In Argentinian Catholic Action, tensions were identified between the definitions of youth produced by the institution and young people's own trajectories. Young people experience ways of «being¼ and «living¼ that are different from those proposed by the Argentinian Catholic Action and that respond to the social and cultural changes produced in Argentine society in recent decades.


Resumo (analítico) O artigo analisa as construções de jovens presentes na Acción Católica Argentina seus vínculos com as trajetórias de jovens militantes inseridos nas paróquias da Gran Buenos Aires. Para a abordagem metodológica qualitativo, são utilizados materiais de campo produzidos entre 2016 e 2018, que consistem em entrevistas em profundidade com jovens católicos; registros de observação participante nas paróquias e eventos nacionais da Acción Católica Argentina e análise de documentos institucionais. Na Acción Católica Argentina, são identificadas tensões entre as definições de juventude produzidas pela instituição e as trajetórias da juventude. Os jovens experimentam maneiras de «ser¼ e «viver¼ a juventude diferentes dos propostos pela Acción Católica Argentina de acordo com as mudanças sociais e culturais produzidas na Argentina nas últimas décadas.


Assuntos
Catolicismo , Observação
18.
Dis Aquat Organ ; 139: 93-102, 2020 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-32351240

RESUMO

Crassicauda spp. (Nematoda) infest the cranial sinuses of several odontocetes, causing diagnostic trabecular osteolytic lesions. We examined skulls of 77 Indian Ocean humpback dolphins Sousa plumbea and 69 Indo-Pacific bottlenose dolphins Tursiops aduncus, caught in bather-protecting nets off KwaZulu-Natal (KZN) from 1970-2017, and skulls of 6 S. plumbea stranded along the southern Cape coast in South Africa from 1963-2002. Prevalence of cranial crassicaudiasis was evaluated according to sex and cranial maturity. Overall, prevalence in S. plumbea and T. aduncus taken off KZN was 13 and 31.9%, respectively. Parasitosis variably affected 1 or more cranial bones (frontal, pterygoid, maxillary and sphenoid). No significant difference was found by gender for either species, allowing sexes to be pooled. However, there was a significant difference in lesion prevalence by age, with immature T. aduncus 4.6 times more likely affected than adults, while for S. plumbea, the difference was 6.5-fold. As severe osteolytic lesions are unlikely to heal without trace, we propose that infection is more likely to have a fatal outcome for immature dolphins, possibly because of incomplete bone development, lower immune competence in clearing parasites or an over-exuberant inflammatory response in concert with parasitic enzymatic erosion. Cranial osteolysis was not observed in mature males (18 S. plumbea, 21 T. aduncus), suggesting potential cohort-linked immune-mediated resistance to infestation. Crassicauda spp. may play a role in the natural mortality of S. plumbea and T. aduncus, but the pathogenesis and population level impact remain unknown.


Assuntos
Crânio , Animais , Golfinhos , Oceano Índico , Masculino , África do Sul
19.
Front Pharmacol ; 11: 113, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32153413

RESUMO

G protein coupled receptor (GPCR) kinases (GRKs) are key regulators of GPCR signaling. Canonical mechanism of GPCR desensitization involves receptor phosphorylation by GRKs followed by arrestin recruitment and uncoupling from heterotrimeric G protein. Although ß3-adrenergic receptor (ß3AR) lacks phosphorylation sites by GRKs, agonist treatment proved to induce ß3AR desensitization in many cell types. Here we show that GRK2 mediates short-term desensitization of ß3AR by a phosphorylation independent mechanism but mediated by its domain homologous to the regulator of G protein signaling (RGS). HEK293T cells overexpressing human ß3AR presented a short-term desensitization of cAMP response stimulated by the ß3AR agonist, BRL37344, and not by forskolin. We found that ß3AR desensitization was higher in cells co-transfected with GRK2. Similarly, overexpression of the RGS homology domain but not kinase domain of GRK2 increased ß3AR desensitization. Consistently, stimulation of ß3AR increased interaction between GRK2 and Gαs subunit. Furthermore, in rat cardiomyocytes endogenously expressing ß3AR, transfection with dominant negative mutant of RH domain of GRK2 (GRK2/D110A) increased cAMP response to BRL37344 and inhibited receptor desensitization. We expect our study to be a starting point for more sophisticated characterization of the consequences of GRK2 mediated desensitization of the ß3AR in heart function and disease.

20.
Rev. argent. cardiol ; 88(1): 41-47, feb. 2020. tab, graf
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1250932

RESUMO

RESUMEN Introducción: Existen claras recomendaciones para el manejo lipídico en los diabéticos. Una nueva fórmula para el cálculo del C-LDL mejoraría la imprecisión de la fórmula de Friedewald. Objetivos: Analizar el uso de estatinas y el cumplimiento de las metas lipídicas en pacientes diabéticos, evaluando las consecuencias de aplicar una nueva fórmula para el cálculo del C-LDL. Métodos: Estudio descriptivo, transversal y multicéntrico. Se incluyeron diabéticos tipo 2 mayores de 18 años. El C-LDL se calculó con la fórmula clásica (Friedewald) y la nueva fórmula. Se siguieron las recomendaciones del documento de posición para el uso adecuado de estatinas (Sociedad Argentina de Cardiología). Resultados: Se incluyeron 528 pacientes. En prevención secundaria, el 77,2% recibió estatinas (23,4% alta intensidad). El 36,6% y el 36,0% alcanzaron la meta de C-LDL menor a 70 mg/dL y de C-noHDL inferior a 100 mg/dL, respectivamente. El 20,8% de los pacientes con un C-LDL menor de 70 mg/dL (Friedewald) salió de meta al aplicar la nueva fórmula. En los pacientes en prevención primaria con factores de riesgo o daño de órgano blanco, el 62,2% recibió estatinas (14,7% alta intensidad). El 20,9% y el 20,4% alcanzaron la meta de C-LDL menor a 70 mg/dL y de C-noHDL inferior a 100 mg/dL. El 27,7% de los pacientes con un C-LDL menor de 70 mg/dL (Friedewald) salió de meta al aplicar la nueva fórmula. A mayor nivel de triglicéridos, más pacientes salieron de meta de C-LDL con la nueva fórmula. Conclusión: El cumplimiento de las metas lipídicas y el uso adecuado de estatinas en esta población fue deficiente. Aplicar la nueva fórmula de C-LDL optimizó la evaluación de estos pacientes.


ABSTRACT Background: There are clear recommendations for lipid management in diabetic patients. A new formula for the calculation of LDL-cholesterol (LDL-C) would improve the inaccuracy of the Friedewald formula. Objectives: The aim of this study was to analyze the use of statins and the fulfillment of lipid goals in diabetic patients, evaluating the consequences of applying a new formula for LDL-C calculation. Methods: This was a descriptive, cross-sectional, multicenter study including type 2 diabetic patients over 18 years of age. LDL-C was calculated using the classic Friedewald formula and the new formula. Recommendations of the position document for the appropriate use of statins from the Argentine Society of Cardiology were followed. Results: A total of 528 patients were included in the study. In secondary prevention, 77.2% of patients received statins (23.4% high-intensity statins) and 36.6% and 36.0% of these patients achieved the goals of LDL-C below 70% mg/dl and non-HDL-C below 100 mg/dl, respectively. In 20.8% of patients with LDL-C below 70 mg/dl according to the Friedewald formula, this goal was not attained when the new formula was applied. In primary prevention, 62.2% patients with risk factors or white organ damage received statins (14.7% high-intensity statins) and 20.9% and 20.4% achieved the goals of LDL-C below 70% mg/dl and non-HDL-C below 100 mg/dl. In 27.7% of patients with LDL-C below 70 mg/dl using the Friedewald formula, this goal was not reached when applying the new formula. More patients did not achieve the LDL-C goal with the new formula when the triglyceride level was higher. Conclusion: In this population, the appropriate use of statins and the fulfillment of lipid goals were poor. Applying the new LDL-C formula optimized the evaluation of these patients.

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