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51.
David R. Bauman Alan Whitehead Lisa C. Contino Jisong Cui Margarita Garcia-Calvo Xin Gu Nancy Kevin Xiuying Ma Lee-yuh Pai Kashmira Shah Xiaolan Shen Sloan Stribling Hratch J. Zokian Joe Metzger Diane E. Shevell Sherman T. Waddell 《Bioorganic & medicinal chemistry letters》2013,23(12):3650-3653
In an effort to understand the origin of blood-pressure lowering effects observed in recent clinical trials with 11β-HSD1 inhibitors, we examined a set of 11β-HSD1 inhibitors in a series of relevant in vitro and in vivo assays. Select 11β-HSD1 inhibitors reduced blood pressure in our preclinical models but most or all of the blood pressure lowering may be mediated by a 11β-HSD1 independent pathway. 相似文献
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Emilya D. Ivanova Nadya I. Ivanova Margarita D. Apostolova Sevdalina C. Turmanova Ivaylo V. Dimitrov 《Bioorganic & medicinal chemistry letters》2013,23(14):4080-4084
Stable, nanosized polyelectrolyte complexes between rationally designed thermally sensitive block copolymers and plasmid DNA (polyplexes) were formed and their in vitro transfection efficiency was tested. The polyplexes were further stabilized through encapsulation into a biodegradable polymer shell. Although reduced as compared to that of the corresponding polyplexes, the encapsulated systems still show acceptable transfection efficiency. That opens the possibility to tune the balance between the safe transport and efficient delivery of DNA into the cells. 相似文献
53.
María G. Cárdenas-Mondragón Ricardo Carreón-Talavera Margarita Camorlinga-Ponce Alejandro Gomez-Delgado Javier Torres Ezequiel M. Fuentes-Pananá 《PloS one》2013,8(4)
Background
H. pylori infection is acquired during childhood and causes a chronic inflammatory response in the gastric mucosa, which is considered the main risk factor to acquire gastric cancer (GC) later in life. More recently, infection by Epstein-Barr virus (EBV) have also been associated with GC. The role of EBV in early inflammatory responses and its relationship with H. pylori infection remains poorly studied. Here, we assessed whether EBV infection in children correlated with the stage of gastritis and whether co-infection with H. pylori affected the severity of inflammation.Methodology/Principal Findings
333 pediatric patients with chronic abdominal pain were studied. From them, gastric biopsies were taken and inflammation graded according to the Sydney system; peripheral blood was drawn and antibodies against EBV (IgG and IgM anti-VCA) and H. pylori (IgG anti-whole bacteria and anti-CagA) were measured in sera. We found that children infected only by EBV presented mild mononuclear (MN) and none polymorphonuclear (PMN) cell infiltration, while those infected by H. pylori presented moderate MN and mild PMN. In contrast, patients co-infected with both pathogens were significantly associated with severe gastritis. Importantly, co-infection of H. pylori CagA+/EBV+ had a stronger association with severe MN (PR 3.0) and PMN (PR 7.2) cells than cases with single H. pylori CagA+ infection.Conclusions/Significance
Co-infection with EBV and H. pylori in pediatric patients is associated with severe gastritis. Even single infections with H. pylori CagA+ strains are associated with mild to moderate infiltration arguing for a cooperative effect of H. pylori and EBV in the gastric mucosa and revealing a critical role for EBV previously un-appreciated. This study points out the need to study both pathogens to understand the mechanism behind severe damage of the gastric mucosa, which could identified children with increased risk to present more serious lesions later in life. 相似文献54.
Vesela Yancheva Elenka Georgieva Stela Stoyanova Iliana Velcheva Dóra Somogyi Krisztián Nyeste László Antal 《Acta zoologica》2020,101(4):431-446
The present study aimed to investigate for the first time the health status of the Caucasian dwarf goby Knipowitschia caucasica (Berg, 1916, Fishes of freshwaters of Russian Empire, p. 563, Moscow, Russia: Dep. Zemledeliya) (Teleostei: Gobiidae) from an anthropogenically loaded site in Hungary using histopathological analyses on multiple tissues. For that purpose, fish were collected from the public beach at Tiszafüred near the River Tisza. Gills, liver and kidney were subjected to histopathological analyses, and the results showed different alterations in each organ, which also differed in their extent and severity. In addition, we also found lesions in the reproductive organs of both, male and female fish which, overall, we hypothesized could be due to untreated municipal wastewaters, most likely contaminated with endocrine-disrupting chemicals. The multi-organ histopathological analyses of Caucasian dwarf gobies revealed different lesions, prevalence and severity in each target organ, as follows: liver>gills>kidney>gonad (testes and ovaries). These histopathological lesions can be assessed as good indicators of contamination by endocrine-disrupting chemicals of freshwater ecosystems. 相似文献
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Foxp3+ regulatory T cells (Tregs) exhibit plasticity, which dictates their function. Secretion of the inflammatory cytokine IFNγ, together with the acquisition of a T helper 1 (Th1)‐like effector phenotype as observed in cancer, infection, and autoimmune diseases, is associated with loss of Treg suppressor function through an unknown mechanism. Here, we describe the signaling events driving the generation of human Th1‐Tregs. Using a genome‐wide gene expression approach and pathway analysis, we identify the PI3K/AKT/Foxo1/3 signaling cascade as the major pathway involved in IFNγ secretion by human Tregs. Furthermore, we describe the opposing roles of AKT isoforms in Th1‐Treg generation ex vivo. Finally, we employ multiple sclerosis as an in vivo model with increased but functionally defective Th1‐Tregs. We show that the PI3K/AKT/Foxo1/3 pathway is activated in ex vivo‐isolated Tregs from untreated relapsing–remitting MS patients and that blockade of the pathway inhibits IFNγ secretion and restores the immune suppressive function of Tregs. These data define a fundamental pathway regulating the function of human Tregs and suggest a novel treatment paradigm for autoimmune diseases. 相似文献