Molecular characterization of a mariner-like element in the Atta sexdens rubropilosa genome

Mobile elements are widely present in eukaryotic genomes. They are repeated DNA segments that are able to move from one locus to another within the genome. They are divided into two main categories, depending on their mechanism of transposition, involving RNA (class I) or DNA (class II) molecules. The mariner-like elements are class II transposons. They encode their own transposase, which is necessary and sufficient for transposition in the absence of host factors. They are flanked by a short inverted terminal repeat and a TA dinucleotide target site, which is duplicated upon insertion. The transposase consists of two domains, an N-terminal inverted terminal repeat binding domain and a C-terminal catalytic domain. We identified a transposable element with molecular characteristics of a mariner-like element in Atta sexdens rubropilosa genome. Identification started from a PCR with degenerate primers and queen genomic DNA templates, with which it was possible to amplify a fragment with mariner transposable-element homology. Phylogenetic analysis demonstrated that this element belongs to the mauritiana subfamily of mariner-like elements and it was named Asmar1. We found that Asmar1 is homologous to a transposon described from another ant, Messor bouvieri. The predicted transposase sequence demonstrated that Asmar1 has a truncated transposase ORF. This study is part of a molecular characterization of mobile elements in the Atta spp genome. Our finding of mariner-like elements in all castes of this ant could be useful to help understand the dynamics of mariner-like element distribution in the Hymenoptera.FAPESPFAPESPCNPqCNP

Molecular characterization of a mariner-like element in the Atta sexdens rubropilosa genome

Mobile elements are widely present in eukaryotic genomes. They are repeated DNA segments that are able to move from one locus to another within the genome. They are divided into two main categories, depending on their mechanism of transposition, involving RNA (class I) or DNA (class II) molecules. The mariner-like elements are class II transposons. They encode their own transposase, which is necessary and sufficient for transposition in the absence of host factors. They are flanked by a short inverted terminal repeat and a TA dinucleotide target site, which is duplicated upon insertion. The transposase consists of two domains, an N-terminal inverted terminal repeat binding domain and a C-terminal catalytic domain. We identified a transposable element with molecular characteristics of a mariner-like element in Atta sexdens rubropilosa genome. Identification started from a PCR with degenerate primers and queen genomic DNA templates, with which it was possible to amplify a fragment with mariner transposable-element homology. Phylogenetic analysis demonstrated that this element belongs to the mauritiana subfamily of mariner-like elements and it was named Asmar1. We found that Asmar1 is homologous to a transposon described from another ant, Messor bouvieri. The predicted transposase sequence demonstrated that Asmar1 has a truncated transposase ORF. This study is part of a molecular characterization of mobile elements in the Atta spp genome. Our finding of mariner-like elements in all castes of this ant could be useful to help understand the dynamics of mariner-like element distribution in the Hymenoptera.FAPESPFAPESPCNPqCNP

Decreased expression of ADAMTS-1 in human breast tumors stimulates migration and invasion

Abstract\ud \ud \ud \ud Background\ud \ud ADAMTS-1 (a disintegrin and metalloprotease with thrombospondin motifs) is a member of the ADAMTS family of metalloproteases. Here, we investigated mRNA and protein levels of ADAMTS-1 in normal and neoplastic tissues using qPCR, immunohistochemistry and immunoblot analyses, and we addressed the role of ADAMTS-1 in regulating migration, invasion and invadopodia formation in breast tumor cell lines.\ud \ud \ud \ud Results\ud \ud In a series of primary breast tumors, we observed variable levels of ADAMTS-1 mRNA expression but lower levels of ADAMTS-1 protein expression in human breast cancers as compared to normal tissue, with a striking decrease observed in high-malignancy cases (triple-negative for estrogen, progesterone and Her-2). This result prompted us to analyze the effect of ADAMTS-1 knockdown in breast cancer cells in vitro. MDA-MB-231 cells with depleted ADAMTS-1 expression demonstrated increased migration, invasion and invadopodia formation. The regulatory mechanisms underlying the effects of ADAMTS-1 may be related to VEGF, a growth factor involved in migration and invasion. MDA-MB-231 cells with depleted ADAMTS-1 showed increased VEGF concentrations in conditioned medium capable of inducing human endothelial cells (HUVEC) tubulogenesis. Furthermore, expression of the VEGF receptor (VEGFR2) was increased in MDA-MB-231 cells as compared to MCF7 cells. To further determine the relationship between ADAMTS-1 and VEGF regulating breast cancer cells, MDA-MB-231 cells with reduced expression of ADAMTS-1 were pretreated with a function-blocking antibody against VEGF and then tested in migration and invasion assays; both were partially rescued to control levels.\ud \ud \ud \ud Conclusions\ud \ud ADAMTS-1 expression was decreased in human breast tumors, and ADAMTS-1 knockdown stimulated migration, invasion and invadopodia formation in breast cancer cells in vitro. Therefore, this series of experiments suggests that VEGF is involved in the effects mediated by ADAMTS-1 in breast cancer cells.This investigation was supported by The State of São Paulo Research Foundation (FAPESP grants 2006/54963-0, 2006/01026-0, 2008/57103-8, 2010/07699-1), and Brazilian National Council for Scientific and Technological Development (CNPq grant 470779/2007-1). The authors also want to thank Dr. Stanley Zucker (Stony Brook University; Stony Brook, NY, USA) and Dr. Rama Khokha (University of Western Ontario, Toronto, Canada) for suggestions made on data analysis

Nasal polyposis : more than a chronic inflammatory disorder : a disease of mechanical dysfunction : the São Paulo position

Introduction The importance of our study lies in the fact that we have demonstrated the occurrence of mechanical dysfunction within polypoid tissues, which promotes the development of polyps in the nasal cavity. Objective To change the paradigm of nasal polyposis (NP). In this new conception, the chronic nasal inflammatory process that occurs in response to allergies, to pollution, to changes in the epithelial barrier, or to other factors is merely the trigger of the development of the disease in individuals with a genetic predisposition to an abnormal tissue remodeling process, which leads to a derangement of the mechanical properties of the nasal mucosa and, consequently, allows it to grow unchecked. Data Synthesis We propose a fundamentally new approach to intervening in the pathological process of NP, addressing biomechanical properties, fluid dynamics, and the concept of surface tension. Conclusion The incorporation of biomechanical knowledge into our understanding of NP provides a new perspective to help elucidate the physiology and the pathology of nasal polyps, and new avenues for the treatment and cure of NP

Cell death and lumen formation in spheroids of MCF-7 cells

3D (three-dimensional) cell culture permits a more integrated analysis of the relationship between cells, inserting them into a structure more closely resembling the cellular microenvironment in vivo. The development of in vitro parameters to approximate in vivo 3D cellular environments makes a less reductionist interpretation of cell biology possible. For breast cells, in vitro 3D culture has proven to be an important tool for the analysis of luminal morphogenesis. A greater understanding of this process is necessary because alterations in the lumen arrangement are associated with carcinogenesis. Following lumen formation in 3D cell culture using laser scanning confocal microscopy, we observed alterations in the arrangement of cytoskeletal components (F-actin and microtubules) and increasing levels of cell death associated with lumen formation. The formation of a polarized monolayer facing the lumen was characterized through 3D reconstructions and the use of TEM (transmission electron microscopy), and this process was found to occur through the gradual clearing of cells from the medullary region of the spheroids. This process was associated with different types of cell death, such as apoptosis, autophagy and entosis. The present study showed that changes in the extracellular matrix associated with long periods of time in 3D cell culture lead to the formation of a lumen in MCF-7 cell spheroids and that features of differentiation such as lumen and budding formation occur after long periods in 3D culture, even in the absence of exogenous extracellular compounds.FAPESP (Fundacao de Amparoa Pesquisa do Estado de Sao Paulo)[06/01026-0]Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)CNPq (Conselho Nacional de Desenvolvimento Cientifico e Tecnologico)Capes (Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Secretaria da Educacao do Estado de Sao PauloSecretaria da Educacao do Estado de Sao Paul

Perfil hematológico de morcegos frugívoros, Artibeus lituratus (Chiroptera: Phyllostomidae)

It was provide a hematological profile of Artibeus lituratus (Phyllostomidae: Stenodermatinae). Animals were collected from October 2017 to February 2018 in an urban forest in the city of Rio de Janeiro, Southeastern Brazil. Males and females showed similar overall mean values for the parameters analyzed. Males had higher values for erythrocytes (RBC), hematocrit and basophils. Females had higher levels of eosinophils than males. The hematological values reported here will serve as reference for future research on health conditions of free-living and captive populations of Artibeus lituratus, as well as for research on pathogens associated with these bats.O presente trabalho estabeleceu o perfil hematológico de morcegos frugívoros de vida livre, A. lituratus (Phyllostomidae: Stenodermatinae). As amostragens foram realizadas de outubro de 2017 a fevereiro de 2018 em uma floresta urbana na cidade do Rio de Janeiro, Sudeste do Brasil. Machos e fêmeas apresentaram valores médios gerais semelhantes para os parâmetros analisados. Os machos apresentaram valores de eritrócitos (RBC), hematócrito e basófilos mais altos. As fêmeas apresentaram níveis mais elevados de eosinófilos que os machos. Os valores hematológicos aqui reportados servirão de referência para pesquisas sobre condições de saúde de populações de Artibeus lituratus em vida livre e de cativeiro, assim como para pesquisas sobre patógenos associados a esses morcegos

Evaluation of Oxidative-Stress Pathway and Recovery of Sudden Sensorineural Hearing Loss

Introduction Although the pathogenesis of sudden sensorineural hearing loss (SSNHL) has been discussed in the literature, many unclear points remain. Several authors have hypothesized that oxidative stress plays a role in the pathogenesis of noise-related hearing loss, as well as in drug- and aging-related hearing loss. Reactive oxygen species (ROS) may contribute to the pathogenesis of SSNHL in a similar way as in cases of ototoxicity, noise-induced hearing loss and presbyacusis. Objective The aim of the present study was to find potential peripheral biomarkers to show the levels of oxidative stress in samples of peripheral blood collected from SSNHL patients with and withouth metabolic disease. Methods In total, 80 consecutive patients with SSNHL were evaluated in the otolaryngology emergency room and outpatient clinic of a tertiary hospital between May 2017 and May 2019. All patients underwent detailed anamnesis, physical examination, audiometry, magnetic resonance imaging (MRI) of the inner ears, and blood tests for serum lipids and plasma activity of thiobarbituric acid reactive species (TBARS). Results No significant effect of malondialdehyde (MDA) activity was observed regarding the hearing recovery of patients who developed SSNHL. Conclusion We did not observe a significant correlation between the concentration of TBARs in the peripheral blood or the presence of arterial hypertension and the severity of the initial hearing loss or the prognosis of hearing recovery in patients with SSNHL. The concentration of TBARs in the peripheral blood may not adequately represent the abnormalities that occur in the intracoclear environment

New Insights on the Effect of TNF Alpha Blockade by Gene Silencing in Noise-Induced Hearing Loss

Noise exposure represents the second most common cause of acquired sensorineural hearing loss and we observed that tumor necrosis factor α (TNFα) was involved in this context. The effect of Tnfα gene silencing on the expression profile related to the TNFα metabolic pathway in an experimental model of noise-induced hearing loss had not previously been studied. Methods: Single ears of Wistar rats were pretreated with Tnfα small interfering RNA (siRNA) by trans-tympanic administration 24 h before they were exposed to white noise (120 dBSPL for three hours). After 24 h of noise exposure, we analyzed the electrophysiological threshold and the amplitude of waves I, II, III, and IV in the auditory brain response click. In addition, qRT-PCR was performed to evaluate the TNFα metabolic pathway in the ears submitted or not to gene silencing. Results: Preservation of the electrophysiological threshold and the amplitude of waves was observed in the ears submitted to gene silencing compared to the ears not treated. Increased anti-apoptotic gene expression and decreased pro-apoptotic gene expression were found in the treated ears. Conclusion: Our results allow us to suggest that the blockade of TNFα by gene silencing was useful to prevent noise-induced hearing loss