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Claudia Emanuele Carvalho-Sousa Eliana P. Pereira Gabriela S. Kinker Mariana Veras Zulma S. Ferreira Fernanda P. Barbosa-Nunes Joilson O. Martins Paulo H.N. Saldiva Russel J. Reiter Pedro A. Fernandes Sanseray da Silveira Cruz-Machado Regina P. Markus 《Journal of pineal research》2020,68(3):e12636
Environmental pollution in the form of particulate matter <2.5 μm (PM2.5) is a major risk factor for diseases such as lung cancer, chronic respiratory infections, and major cardiovascular diseases. Our goal was to show that PM2.5 eliciting a proinflammatory response activates the immune-pineal axis, reducing the pineal synthesis and increasing the extrapineal synthesis of melatonin. Herein, we report that the exposure of rats to polluted air for 6 hours reduced nocturnal plasma melatonin levels and increased lung melatonin levels. Melatonin synthesis in the lung reduced lipid peroxidation and increased PM2.5 engulfment and cell viability by activating high-affinity melatonin receptors. Diesel exhaust particles (DEPs) promoted the synthesis of melatonin in a cultured cell line (RAW 264.7 cells) and rat alveolar macrophages via the expression of the gene encoding for AANAT through a mechanism dependent on activation of the NFκB pathway. Expression of the genes encoding AANAT, MT1, and MT2 was negatively correlated with cellular necroptosis, as disclosed by analysis of Gene Expression Omnibus (GEO) microarray data from the human alveolar macrophages of nonsmoking subjects. The enrichment score for antioxidant genes obtained from lung gene expression data (GTEx) was significantly correlated with the levels of AANAT and MT1 but not the MT2 melatonin receptor. Collectively, these data provide a systemic and mechanistic rationale for coordination of the pineal and extrapineal synthesis of melatonin by a standard damage-associated stimulus, which activates the immune-pineal axis and provides a new framework for understanding the effects of air pollution on lung diseases. 相似文献
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Nicole A. Weitz M.D. Christine T. Lauren M.D. Gerald G. Behr M.D. June K. Wu M.D. Jessica J. Kandel M.D. Philip M. Meyers M.D. Sally Sultan M.D. Kwame Anyane‐Yeboa M.D. Kimberly D. Morel M.D. Maria C. Garzon M.D. 《Pediatric dermatology》2015,32(1):76-84
Capillary malformation–arteriovenous malformation syndrome (CM‐AVM) is an autosomal dominant disorder caused by RASA1 mutations. The prevalence and phenotypic spectrum are unknown. Evaluation of patients with multiple CMs is challenging because associated AVMs can be life threatening. The objective of this study was to describe the clinical characteristics of children presenting with features of CM‐AVM to an academic pediatric dermatology practice. After institutional review board approval was received, a retrospective chart review was performed of patients presenting between 2009 and 2012 with features of CM‐AVM. We report nine cases. Presenting symptoms ranged from extensive vascular stains and cardiac failure to CMs noted incidentally during routine skin examination. All demonstrated multiple CMs, two had Parkes Weber syndrome, and two had multiple infantile hemangiomas. Seven patients had family histories of multiple CMs; three had family histories of large, atypical CMs. Six had personal or family histories of AVMs. Genetic evaluation was recommended for all and was pursued by six families; four RASA1 mutations were identified, including one de novo. Consultations with neurology, cardiology, and orthopedics were recommended. Most patients (89%) have not required treatment to date. CM‐AVM is an underrecognized condition with a wide clinical spectrum that often presents in childhood. Further evaluation may be indicated in patients with multiple CMs. This study is limited by its small and retrospective nature. 相似文献
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Résumé La double infection d'une même cellule deG. mellonella par le virus irisant de Tipula (TIV) et le virus de la densonucléose (VDN) résulte en une production simultanée de ces deux types de virions. La réplication a lieu dans le cytoplasme pour le TIV et dans le noyau pour le VDN des cellules adipeuses de l'hypoderme, des canaux des glandes séricigènes de la glande de mue et des hémocytes. L'infection suivie par histochimie a permis de confirmer la nature bicaténaire du DNA du TIV et la nature monocaténaire du DNA du VDN. La microscopie électronique a révélé les étapes de la morphogenèse de ces deux virus.
Simultaneous replication of two DNA viruses
Summary The double infection of single cell ofG. mellonella by Tipula iridescent virus (TIV) and by Densonucleosis virus (DNV) result into a simultaneous production of these two types of virions. The replication occurs in the cytoplasm in the case of TIV and in the nucleus in the case of DNV in adipose, hypodermal, silk gland, moulting gland and hemocyte cells. The infection followed by histochemical studies has confirmed that the DNA is double stranded for TIV and is single stranded for DNV. Electron microscopy study revealed the morphogenesis of these two viruses during the double infection.相似文献
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Anton A. Apostolov Eliana Bosvelieva Alexander Du Chesne Konstantin Goranov Stoyko Fakirov 《Macromolecular chemistry and physics.》1993,194(8):2267-2277
Isotropic unannealed and annealed melt-pressed and quenched samples of segmented multiblock poly(ether-ester-amide)s based on polyamide-6 and poly(ethylene glycol)s (PEGs) of molecular weights 400 and 1000 with various hard/soft segment weight ratios were investigated. The effect of composition, segment length and annealing temperature on the crystal structure was studied by differential scanning calorimetry, wide-angle and small-angle X-ray scattering. In addition to the γ-phase, one of the unannealed samples having relatively long hard and soft segments exhibits a high amount of α-phase. This is assumed to be due to the high flexibility of the PEG segments, linking the polyamide blocks thus enhancing their mobility. The lack of hydrogen bonds between the PEG segments facilitates crystallization of the polyamide segments in the more perfect α-modification, which is the most pronounced in the above mentioned sample. Part of the α-phase transforms into the α-phase upon annealing in all copolymer samples studied, similarly to polyamide-6. 相似文献
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Dr. Carlo Clerici Giorgio Gentili Enrico Boschetti Carla Santucci Aaron Garzon Aburbeh Benedetto Natalini Roberto Pellicciari Antonio Morelli 《Digestive diseases and sciences》1994,39(12):2601-2606
In an attempt to obtain site-specific delivery of 5-ASA in the intestinal tract, we have determined the extent of absorption and metabolism of a number of novel 5-ASA derivatives, namely, (N-l-glutamyl)-amino-2-salicylic acid (1), (N-l-aspartyl)-amino-2-salicylic-acid (2), 5-aminosalicyl-l-proline-l-leucine (3), and 5-(N-l-glutamyl)-aminosalicyl-l-proline-l-leucine (4), which are selectively cleaved by intestinal brush border aminopeptidase A and carboxypeptidases. These novel prodrugs, 5-ASA, and sulfasalazine were administered to adult Fisher rats (N=30) and to animals that had undergone prior colostomy (N=30). Urine and feces were collected at timed intervals for 48 hr and the metabolites, 5-ASA, andN-acetyl-5-ASA were measured by high-performance liquid chromatography. The absorption and metabolism of all compounds were essentially identical in colostomized and normal animals. 5-ASA exhibited a rapid proximal intestinal absorption as evidenced by the high cumulative urinary excretion (>65%) and low fecal excretion. Sulfasalazine, as expected, exhibited a lower urinary recovery (<35%) and higher fecal excretion of 5-ASA and its metabolite. The novel glutamate and aspartate derivatives (1 and2) behaved similarly to sulfasalazine, while administration of the proline-leucine derivative (3) resulted in urinary and fecal recovery values intermediate with respect to those observed with 5-ASA and sulfasalazine. 5-(N-l-Glutamyl)-aminosalicyl-l-proline-l-leucine yielded the highest fecal recovery of 5-ASA and itsN-acetyl derivative, indicating a more efficient delivery to the distal bowel. Amino acid derivatives of 5-ASA appear to be potentially useful prodrugs for the site-specific delivery of 5-ASA to different regions of the intestinal tract.We acknowledge the Depha Team for financial support and Dr. Kenneth D.R. Setchell for discussions. 相似文献