The Arabidopsis translocator protein (AtTSPO) is regulated at multiple levels in response to salt stress and perturbations in tetrapyrrole metabolism

<p>Abstract</p> <p>Background</p> <p>The translocator protein 18 kDa (TSPO), previously known as the peripheral-type benzodiazepine receptor (PBR), is important for many cellular functions in mammals and bacteria, such as steroid biosynthesis, cellular respiration, cell proliferation, apoptosis, immunomodulation, transport of porphyrins and anions. <it>Arabidopsis thaliana </it>contains a single <it>TSPO/PBR</it>-related gene with a 40 amino acid N-terminal extension compared to its homologs in bacteria or mammals suggesting it might be chloroplast or mitochondrial localized.</p> <p>Results</p> <p>To test if the TSPO N-terminal extension targets it to organelles, we fused three potential translational start sites in the <it>TSPO </it>cDNA to the N-terminus of GFP (<it>At</it>TSPO:eGFP). The location of the <it>At</it>TSPO:eGFP fusion protein was found to depend on the translational start position and the conditions under which plants were grown. Full-length <it>At</it>TSPO:eGFP fusion protein was found in the endoplasmic reticulum and in vesicles of unknown identity when plants were grown in standard conditions. However, full length <it>At</it>TSPO:eGFP localized to chloroplasts when grown in the presence of 150 mM NaCl, conditions of salt stress. In contrast, when <it>At</it>TSPO:eGFP was truncated to the second or third start codon at amino acid position 21 or 42, the fusion protein co-localized with a mitochondrial marker in standard conditions. Using promoter <it>GUS </it>fusions, qRT-PCR, fluorescent protein tagging, and chloroplast fractionation approaches, we demonstrate that <it>At</it>TSPO levels are regulated at the transcriptional, post-transcriptional and post-translational levels in response to abiotic stress conditions. Salt-responsive genes are increased in a <it>tspo-1 knock-down </it>mutant compared to wild type under conditions of salt stress, while they are decreased when <it>At</it>TSPO is overexpressed. Mutations in tetrapyrrole biosynthesis genes and the application of chlorophyll or carotenoid biosynthesis inhibitors also affect <it>AtTSPO </it>expression.</p> <p>Conclusion</p> <p>Our data suggest that AtTSPO plays a role in the response of <it>Arabidopsis </it>to high salt stress. Salt stress leads to re-localization of the AtTSPO from the ER to chloroplasts through its N-terminal extension. In addition, our results show that <it>AtTSPO </it>is regulated at the transcriptional level in tetrapyrrole biosynthetic mutants. Thus, we propose that <it>At</it>TSPO may play a role in transporting tetrapyrrole intermediates during salt stress and other conditions in which tetrapyrrole metabolism is compromised.</p

Dolosigranulum pigrum modulates immunity against SARS-CoV-2 in respiratory epithelial cells

In a previous work, we demonstrated that nasally administered Dolosigranulum pigrum 040417 beneficially modulated the respiratory innate immune response triggered by the activation of Toll-like receptor 3 (TLR3) and improved protection against Respiratory Syncytial Virus (RSV) in mice. In this work, we aimed to evaluate the immunomodulatory effects of D. pigrum 040417 in human respiratory epithelial cells and the potential ability of this immunobiotic bacterium to in-crease the protection against Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2). The respiratory commensal bacterium D. pigrum 040417 differentially modulated the production of IFN-β, IL-6, CXCL8, CCL5 and CXCL10 in the culture supernatants of Calu-3 cells stimulated with poly(I:C) or challenged with SARS-CoV-2. The differential cytokine profile induced by the 040417 strain was associated with a significant reduction in viral replication and cellular damage after coronavirus infection. Of note, D. pigrum 030918 was not able to modify the resistance of Calu-3 cells to SARS-CoV-2 infection, indicating a strain-specific immunomodulatory effect for respiratory commensal bacteria. The findings of this work improve our understanding of the immunological mechanisms involved in the modulation of respiratory immunity induced by respiratory commensal bacteria, by demonstrating their specific effect on respiratory epithelial cells. In addition, the results suggest that particular strains such as D. pigrum 040417 could be used as a promising alternative for combating SARS-CoV-2 and reducing the severity of COVID-19.Fil: Islam, Md Aminul. Tohoku University; Japón. Bangladesh Agricultural University; BangladeshFil: Albarracín, Leonardo Miguel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Centro de Referencia para Lactobacilos; ArgentinaFil: Melnikov, Vyacheslav. Gabrichevsky Research Institute for Epidemiology and Microbiology; RusiaFil: Andrade, Bruno G. N.. Munster Technological University; IrlandaFil: Cuadrat, Rafael R. C.. Berlín Institute for Medical Systems Biology; AlemaniaFil: Kitazawa, Haruki. Tohoku University; JapónFil: Villena, Julio Cesar. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Centro de Referencia para Lactobacilos; Argentin

Potential contribution of selected metallic restorative dentistry materials to X-ray fluorescence

Recent advances have led to the use of new materials in dental restoration which is an area of rapid growth. Applications include improving oral aesthetics and essential rehabilitation, whilst procedures range from the recovery of partial elements (inlays) to fitting dental implants. Ceramics, polymers and metallic materials have all been successfully employed in dental applications and benefit from new cost efficient manufacturing techniques. The application of radiographic techniques in dentistry and other medicine is also increasing, and the combination of new materials and radiation can lead to an elevated health risk. X-rays can interact with metallic materials producing X-ray fluorescence, which can increase the radiation dose in proximity to restorative material and increase the risk of live biological tissue becoming cancerous. The issue demands consideration so that the biological risks associated with such procedures are kept as low as possible. Comparisons of doses calculated for several materials have provided evidence that the Ti cp and NiCrTi alloys present less contribution to the increase of dose in surrounding soft tissue and the potential deleterious biological effects. On the other hand, Amalgam appears to be the most deleterious alloy

Association between decreases in type V collagen and apoptosis in mouse lung chemical carcinogenesis: a preliminary model to study cancer cell behavior

OBJECTIVE: The importance of type V collagen and its relationships with other types of collagen and with vascular and epithelial apoptosis were studied in a model of chemical carcinogenesis in the mouse lung. METHODS: Two groups of male Balb/c mice were studied: a) animals that received two intraperitoneal doses of 3 g/kg urethane carcinogen (urethane group = 24); and b) animals submitted to a sham procedure, comparable to the test group (control group = 7). Both groups were sacrificed after 120 days. In situ detection of apoptosis, immunohistochemistry, immunofluorescence and histomorphometry were used to evaluate the fraction occupied by the tumor, vascular and epithelial apoptosis, and type V, III and I collagen fibers in the lung parenchyma from both groups. RESULTS: The lung parenchyma from the urethane group showed low fractions of vascular and epithelial apoptosis as well as reduced type V collagen fibers when compared to the control group. A significant direct association was found between type V and III collagen fibers and epithelial apoptosis, type V collagen fibers and vascular apoptosis, and type V and type I collagen fibers. CONCLUSION: The results show that a direct link between low amounts of type V collagen and decreased cell apoptosis may favor cancer cell growth in the mouse lung after chemical carcinogenesis, suggesting that strategies aimed at preventing decreased type V collagen synthesis or local responses to reduced apoptosis may have a greater impact in lung cancer control

Lipid-laden multilocular cells in the aging thymus are phenotypically heterogeneous

Intrathymic lipid-laden multilocular cells (LLMC) are known to express pro-inflammatory factors that might regulate functional activity of the thymus. However, the phenotype of ageassociated intrathymic LLMC is still controversial. In this study, we evaluated LLMC density in the aging thymus and better characterized their distribution, ultrastructure and phenotype. Our results show an increased density of LLMC in the thymus from 03 to 24 months of age. Morphologically, intrathymic LLMC exhibit fibroblastoid fusiform, globular or stellate shapes and can be found in the subcapsular region as well as deeper in the parenchyma, including the perivascular area. Some parenchymal LLMC were like telocytes accumulating lipids. We identified lipid droplets with different electrondensities, lipofuscin granules and autolipophagosomelike structures, indicating heterogeneous lipid content in these cells. Autophagosome formation in intrathymic LLMC was confirmed by positive staining for beclin-1 and perilipin (PLIN), marker for lipid droplet-associated proteins.We also found LLMC in close apposition to thymic stromal cells, endothelial cells, mast cells and lymphocytes. Phenotypically, we identified intrathymic LLMC as preadipocytes (PLIN+PPARγ2+), brown adipocytes (PLIN+UCP1+), macrophages (PLIN+Iba-1+) or pericytes (PLIN+NG2+) but not epithelial cells (PLIN- panCK+). These data indicate that intrathymic LLMC are already present in the young thymus and their density significantly increases with age. We also suggest that LLMC, which are morphologically distinct, establish direct contact with lymphocytes and interact with stromal cells. Finally, we evidence that intrathymic LLMC correspond to not only one but to distinct cell types accumulating lipids

Cochlear ribbon synapse maturation requires Nlgn1 and Nlgn3

Hearing depends on precise synaptic transmission between cochlear inner hair cells and spiral ganglion neurons through afferent ribbon synapses. Neuroligins (Nlgns) facilitate synapse maturation in the brain, but they have gone unstudied in the cochlea. We repor

Lyra: Password-Based Key Derivation with Tunable Memory and Processing Costs

We present Lyra, a password-based key derivation scheme based on cryptographic sponges. Lyra was designed to be strictly sequential (i.e., not easily parallelizable), providing strong security even against attackers that use multiple processing cores (e.g., custom hardware or a powerful GPU). At the same time, it is very simple to implement in software and allows legitimate users to fine-tune its memory and processing costs according to the desired level of security against brute force password guessing. We compare Lyra with similar-purpose state-of-the-art solutions, showing how our proposal provides a higher security level and overcomes limitations of existing schemes. Specfically, we show that if we fix Lyra\u27s total processing time t in a legitimate platform, the cost of a memory-free attack against the algorithm is exponential, while the best known result in the literature (namely, against the scrypt algorithm) is quadratic. In addition, for an identical same processing time, Lyra allows for a higher memory usage than its counterparts, further increasing the cost of brute force attacks

Management and destination for residues from electrical discharge lamps

The use of gas discharge lamps is an important instrument to reduce energy demand and to increase efficiency at the end use of energy. It has been considered under the electrical energy reduction purposes. In this work the environment point of view was aggregated. After the bulb life time end the final destination of the harmful elements contained in it must be treated with focus on management of hazardous waste. Large data variability on the amount of Mercury (Hg) detected inside the discharge tube of the lamps were observed, particularly at fluorescent bulbs. The current situation in Brazil, where electricity generation is not based on burning coal and a greater market diffusion of bulbs based on Hg technology can induce increase in the emission of Hg during the bulb life cycle, unlike at the U.S. and other countries. Investments for the main equipments to quantify Hg content in discharge tubes from lamps were discussed and estimated.A utilização de fonte de luz elétrica eficiente tem sido uma prática crescente e atual, mesmo quando esse produto deixa de ser produzido localmente e necessita ser importado. Numa avaliação exclusivamente sob o prisma energético e quando comparada com fonte incandescente: a lâmpada a descarga em gases pode reduzir a demanda de energia elétrica e aumentar a eficiência em uso final. Neste artigo a análise que foi realizada agregou base ambiental importante. Terminada a vida útil da lâmpada a descarga, o destino final deve ser melhor considerado e com foco na gestão de resíduos perigosos. É bastante ampla a variabilidade que pode ser observada na literatura em relação á quantidade de Mercúrio (Hg) presente em lâmpadas a descarga, particularmente aquelas do tipo fluorescente. Na situação brasileira atual, cuja geração de eletricidade não tem base predominante na queima de carvão, uma maior difusão no mercado local de fonte de luz com base no Hg pode induzir uma elevação na emissão desse elemento nocivo durante o ciclo de vida da lâmpada, diferentemente dos EUA e outros países. O Hg e os resíduos potencialmente perigosos, particularmente aqueles que são encontrados nas fontes primárias de luz elétrica artificial, utilizadas localmente, deverão ser monitorados e controlados. Eles não devem continuar sendo descartados juntamente aos demais resíduos humanos e recolhidos sem qualquer cuidado especial e eficaz. Investimentos e necessidades para adequação de espaço laboratorial e aquisição dos principais equipamentos para quantificar Hg contido em tubos de descarga elétrica em lâmpadas foram discutidos e dimensionados.Asociación de Universidades Grupo Montevide

Immunobiotic lactobacilli improve resistance of respiratory epithelial cells to sars-cov-2 infection

Previously, we reported that immunomodulatory lactobacilli, nasally administered, benefi-cially regulated the lung antiviral innate immune response induced by Toll-like receptor 3 (TLR3) activation and improved protection against the respiratory pathogens, influenza virus and respiratory syncytial virus in mice. Here, we assessed the immunomodulatory effects of viable and non-viable Lactiplantibacillus plantarum strains in human respiratory epithelial cells (Calu-3 cells) and the capacity of these immunobiotic lactobacilli to reduce their susceptibility to the acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. Immunobiotic L. plantarum MPL16 and CRL1506 differentially modulated IFN-β, IL-6, CXCL8, CCL5 and CXCL10 production and IFNAR2, DDX58, Mx1 and OAS1 expression in Calu-3 cells stimulated with the TLR3 agonist poly(I:C). Furthermore, the MPL16 and CRL1506 strains increased the resistance of Calu-3 cells to the challenge with SARS-CoV-2. L. plantarum MPL16 induced these beneficial effects more efficiently than the CRL1506 strain. Of note, neither non-viable MPL16 and CRL1506 strains nor the non-immunomodulatory strains L. plantarum CRL1905 and MPL18 could modify the resistance of Calu-3 cells to SARS-CoV-2 infection or the immune response to poly(I:C) challenge. To date, the potential beneficial effects of immunomodulatory probiotics on SARS-CoV-2 infection and COVID-19 outcome have been extrapolated from studies carried out in the context of other viral pathogens. To the best of our knowledge, this is the first demonstration of the ability of immunomodulatory lactobacilli to positively influence the replication of the new coronavirus. Further mechanistic studies and in vivo experiments in animal models of SARS-CoV-2 infection are necessary to identify specific strains of beneficial immunobiotic lactobacilli like L. plantarum MPL16 or CRL1506 for the prevention or treatment of the COVID-19.Fil: Islam, Md Aminul. Tohoku University; JapónFil: Albarracín, Leonardo Miguel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Centro de Referencia para Lactobacilos; ArgentinaFil: Tomokiyo, Mikado. Tohoku University; JapónFil: Valdéz, Juan Carlos. Universidad Nacional de Tucumán; ArgentinaFil: Sacur, Jacinto Alfredo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto Superior de Investigaciones Biológicas. Universidad Nacional de Tucumán. Instituto Superior de Investigaciones Biológicas; ArgentinaFil: Vizoso Pinto, María Guadalupe. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto Superior de Investigaciones Biológicas. Universidad Nacional de Tucumán. Instituto Superior de Investigaciones Biológicas; ArgentinaFil: Andrade, Bruno G. N.. No especifíca;Fil: Cuadrat, Rafael R. C.. No especifíca;Fil: Kitazawa, Haruki. Tohoku University; JapónFil: Villena, Julio Cesar. Tohoku University; Japón. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Centro de Referencia para Lactobacilos; Argentin