95 research outputs found

    Modulation of Streptomycin Killing Rate against Mature Escherichia Coli Biofilms in the Presence of Medicinal Plant Extracts

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    Background. Medicinal plant extracts exhibiting pro- and antioxidant properties may affect antibiotic-induced killing of biofilm-producing bacteria in both synergistic and antagonistic modes. Better understanding of these alternations is required to adjust antibiotic therapy and herbal medicine in order to exclude unwanted losses of antibiotic efficiency.Aim: to study modulation modes of streptomycin killing rate against mature biofilms of Escherichia coli in the presence of different doses of commonly used medicinal plant extracts.Materials and methods. Pharmacodynamic parameter killing rate and mass biofilm formation were determined in the presence of streptomycin and medicinal plant extracts.Results. Synergism was found between 100 mg/ml streptomycin and low doses (0.83 mg of dry herb/ml) of green, black tea, Arctostaphylos uva-ursi, Betula pendula and Laminaria japonica against killing mature biofilms. Alternatively, high doses (6.64 mg of dry herb/ml) of green, black tea and Vaccinium vitis-ideae demonstrated antagonism, decreasing killing rate and enhancing biofilm formation. Presumably, high doses of the extracts were sufficient to enhance biofilm formation blocking penetration of streptomycin through enlarged biofilm matrix and diminishing the killing rate.Conclusions. Widely consumed as soft beverages or for prophylactic purposes green, black tea and V. vitis-ideae could promote strong antagonistic effects with streptomycin. These extracts can stimulate biofilm production, making benefit for commensal microbiota, but have clinical relevance due to a significant reduction in the lethal efficiency of streptomycin in biofilms of pathogenic strains. This highlights the need of careful antibiotic prescription scheme adjustment when choosing appropriate combinations of plant extracts and antibiotics to achieve a synergistic effect

    Alma-Ata to Berlin: diabetes prevention and treatment to achieve healthy living

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    Bharti Hosp, Dept Endocrinol, Karnal, Haryana, IndiaAarhus Univ, Dept Publ Hlth, Aarhus, DenmarkKazakh Acad Nutr, Alma Ata, KazakhstanAcad Prevent Med, Alma Ata, KazakhstanKazakh Natl Med Univ, Alma Ata, KazakhstanDubai Hosp, Dept Endocrinol, Dubai, U Arab EmiratesPondicherry Inst Med Sci, Dept Med, Pondicherry, IndiaMinist Hlth, Directorate Epidemiol, Mexico City, DF, MexicoItalian Coll Gen Practitioners, Florence, ItalyUniv Hlth Network, Toronto, ON, CanadaSiberian State Med Univ, Tomsk, RussiaInst Diabet Endocrinol & Metab Dis, Endocrinol Res Ctr, Moscow, RussiaUniv Fed São Paulo, Dept Med, São Paulo, BrazilPrimary Care Diabet Europe, Barcelona, SpainDubai Hlth Author, Dubai, U Arab EmiratesPeking Union Med Coll, Beijing, Peoples R ChinaUniv Fed São Paulo, Dept Med, São Paulo, BrazilWeb of Scienc

    INVESTIGATING THE ROLE OF STRESS-REGULONS IN MODULATING EFFECTS OF PLANT EXTRACTS ON BACTERIAL BIOFILMS

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    Among 18 plant extracts studied black tea, A. uva ursi, V. vitis-idaea, T. сordata, B. pendula and Z. mays stimulated biofilm formation, while the extracts of A. millefolium, U. dioica and L. japonica demonstrated inhibiting effects. Some of the extracts also inhibited rpoS expression both in biofilms and planktonic cultures. To elucidate the role of RpoS sigma-S factor in the observed effects of the plant extracts, we studied influence of different doses of pure plant polyphenol quercetin on biofilm formation in strains with different levels of RpoS. It was found that negative influence on biofilm formation was due to the RpoS excess. Collectively, our data indicate the possibility of RpoS-independent pathway of biofilm formation regulation in the pres-ence of plant extracts containing polyphenols.Исследование выполнено при поддержке грантом РФФИ-Урал № 14-04-96031, грантом №12-И-4-2072 по Программе интеграционных проектов Президиума УрО РАН, а также грантом Президиума УрО РАН для молодых ученых 14-4-НП-126

    ELEVATE-TN Study. New data of acalabrutinib in first-line treatment of chronic lymphocytic leukemia. Resolution

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    Over the past decade, we have seen a significant change in modern approaches in the first-line treatment of chronic lymphocytic leukemia (CLL). The CLL-10 study data established the FCR regimen as the treatment of choice for younger patients with limited comorbidities, while for patients older than 65 years, the BR regimen is more often considered as less toxic one. According to published data, 46% of patients with newly diagnosed CLL have comorbidities. Moreover, high-risk patients with del(17p) and/or TP53 mutation do not have response on immunochemotherapy (ICT) most often. Thus, about 1/2 of the patients cannot be treated or will not respond to standard ICT regimens. Targeted therapy with Brutons tyrosine kinase (BTK) inhibitors is an important option of the first-line treatment of patients with CLL. Acalabrutinib is a highly selective second-generation BTK inhibitor that does not inhibit EGFR, ITK or TEC targets. Acalabrutinib in combination with obinutuzumab or as monotherapy can be considered as a highly effective and safe option of the first line of CLL therapy. Based on the hight selectivity of the agent, acalabrutinib can be considered as the preferable option for patients who are not eligible for ICT, including patients with commodities, such as cardiovascular diseases or risk factors for their development

    Interleukin-6 Induces Gr-1+CD11b+ Myeloid Cells to Suppress CD8+ T Cell-Mediated Liver Injury in Mice

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    Agonist antibodies against CD137 (4-1BB) on T lymphocytes are used to increase host anti-tumor immunity, but often leading to severe liver injury in treated mice or in patients during clinical trials. Interleukin-6 (IL-6) has been reported to protect hepatocyte death, but the role of IL-6 in protecting chronic T cell-induced liver diseases is not clearly defined due to lack of relevant animal models. We aimed to define the role of IL-6 in CD8+ T cell-mediated liver injury induced by a CD137 agonistic mAb (clone 2A) in mice.We expressed IL-6 in the liver by hydrodynamic gene delivery in mice treated with 2A or control mAb and studied how IL-6 treatment affected host immunity and T cell-mediated liver injury. We found that ectopic IL-6 expression in the liver elevated intrahepatic leukocyte infiltration but prevented CD8+ T cell-mediated liver injury. In IL-6 treated mice, CD8+ T cells proliferation and IFN-γ expression were inhibited in the liver. We discovered that IL-6 increased accumulation of Gr-1+CD11b+ myeloid derived suppressor cells (MDSCs) in the liver and spleen. These MDSCs had the ability to inhibit T cells proliferation and activation. Finally, we showed that the MDSCs were sufficient and essential for IL-6-mediated protection of anti-CD137 mAb-induced liver injury.We concluded that IL-6 induced Gr-1+CD11b+ MDSCs in the liver to inhibit T cell-mediated liver injury. The findings have defined a novel mechanism of IL-6 in protecting liver from CD8+ T cell-mediated injury

    CXCL1 can be regulated by IL-6 and promotes granulocyte adhesion to brain capillaries during bacterial toxin exposure and encephalomyelitis

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    <p>Abstract</p> <p>Background</p> <p>Granulocytes generally exert protective roles in the central nervous system (CNS), but recent studies suggest that they can be detrimental in experimental autoimmune encephalomyelitis (EAE), the most common model of multiple sclerosis. While the cytokines and adhesion molecules involved in granulocyte adhesion to the brain vasculature have started to be elucidated, the required chemokines remain undetermined.</p> <p>Methods</p> <p>CXCR2 ligand expression was examined in the CNS of mice suffering from EAE or exposed to bacterial toxins by quantitative RT-PCR and <it>in situ </it>hybridization. CXCL1 expression was analyzed in IL-6-treated endothelial cell cultures by quantitative RT-PCR and ELISA. Granulocytes were counted in the brain vasculature after treatment with a neutralizing anti-CXCL1 antibody using stereological techniques.</p> <p>Results</p> <p>CXCL1 was the most highly expressed ligand of the granulocyte receptor CXCR2 in the CNS of mice subjected to EAE or infused with lipopolysaccharide (LPS) or pertussis toxin (PTX), the latter being commonly used to induce EAE. IL-6 upregulated CXCL1 expression in brain endothelial cells by acting transcriptionally and mediated the stimulatory effect of PTX on CXCL1 expression. The anti-CXCL1 antibody reduced granulocyte adhesion to brain capillaries in the three conditions under study. Importantly, it attenuated EAE severity when given daily for a week during the effector phase of the disease.</p> <p>Conclusions</p> <p>This study identifies CXCL1 not only as a key regulator of granulocyte recruitment into the CNS, but also as a new potential target for the treatment of neuroinflammatory diseases such as multiple sclerosis.</p

    rs1004819 Is the Main Disease-Associated IL23R Variant in German Crohn's Disease Patients: Combined Analysis of IL23R, CARD15, and OCTN1/2 Variants

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    The IL23R gene has been identified as a susceptibility gene for inflammatory bowel disease (IBD) in the North American population. The aim of our study was to test this association in a large German IBD cohort and to elucidate potential interactions with other IBD genes as well as phenotypic consequences of IL23R variants. Genomic DNA from 2670 Caucasian individuals including 833 patients with Crohn's disease (CD), 456 patients with ulcerative colitis (UC), and 1381 healthy unrelated controls was analyzed for 10 IL23R SNPs. Genotyping included the NOD2 variants p.Arg702Trp, p.Gly908Arg, and p.Leu1007fsX1008 and polymorphisms in SLC22A4/OCTN1 (1672 C-->T) and SLC22A5/OCTN2 (-207 G-->C). All IL23R gene variants analyzed displayed highly significant associations with CD. The strongest association was found for the SNP rs1004819 [P = 1.92x10(-11); OR 1.56; 95 % CI (1.37-1.78)]. 93.2% of the rs1004819 TT homozygous carriers as compared to 78% of CC wildtype carriers had ileal involvement [P = 0.004; OR 4.24; CI (1.46-12.34)]. The coding SNP rs11209026 (p.Arg381Gln) was protective for CD [P = 8.04x10(-8); OR 0.43; CI (0.31-0.59)]. Similar, but weaker associations were found in UC. There was no evidence for epistasis between the IL23R gene and the CD susceptibility genes CARD15 and SLC22A4/5. IL23R is an IBD susceptibility gene, but has no epistatic interaction with CARD15 and SLC22A4/5. rs1004819 is the major IL23R variant associated with CD in the German population, while the p.Arg381Gln IL23R variant is a protective marker for CD and UC

    Differential utilization of ketone bodies by neurons and glioma cell lines: a rationale for ketogenic diet as experimental glioma therapy

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    Background: Even in the presence of oxygen, malignant cells often highly depend on glycolysis for energy generation, a phenomenon known as the Warburg effect. One strategy targeting this metabolic phenotype is glucose restriction by administration of a high-fat, low-carbohydrate (ketogenic) diet. Under these conditions, ketone bodies are generated serving as an important energy source at least for non-transformed cells. Methods: To investigate whether a ketogenic diet might selectively impair energy metabolism in tumor cells, we characterized in vitro effects of the principle ketone body 3-hydroxybutyrate in rat hippocampal neurons and five glioma cell lines. In vivo, a non-calorie-restricted ketogenic diet was examined in an orthotopic xenograft glioma mouse model. Results: The ketone body metabolizing enzymes 3-hydroxybutyrate dehydrogenase 1 and 2 (BDH1 and 2), 3-oxoacid-CoA transferase 1 (OXCT1) and acetyl-CoA acetyltransferase 1 (ACAT1) were expressed at the mRNA and protein level in all glioma cell lines. However, no activation of the hypoxia-inducible factor-1alpha (HIF-1alpha) pathway was observed in glioma cells, consistent with the absence of substantial 3-hydroxybutyrate metabolism and subsequent accumulation of succinate. Further, 3-hydroxybutyrate rescued hippocampal neurons from glucose withdrawal-induced cell death but did not protect glioma cell lines. In hypoxia, mRNA expression of OXCT1, ACAT1, BDH1 and 2 was downregulated. In vivo, the ketogenic diet led to a robust increase of blood 3-hydroxybutyrate, but did not alter blood glucose levels or improve survival. Conclusion: In summary, glioma cells are incapable of compensating for glucose restriction by metabolizing ketone bodies in vitro, suggesting a potential disadvantage of tumor cells compared to normal cells under a carbohydrate-restricted ketogenic diet. Further investigations are necessary to identify co-treatment modalities, e.g. glycolysis inhibitors or antiangiogenic agents that efficiently target non-oxidative pathways

    More stories on Th17 cells

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    For more than two decades, immunologists have been using the so-called Th1/Th2 paradigm to explain most of the phenomena related to adaptive immunity. the Th1/Th2 paradigm implied the existence of two different, mutually regulated, CD4(+) T helper subsets: Th1 cells, driving cell-mediated immune responses involved in tissue damage and fighting infection against intracellular parasites; and Th2 cells that mediate IgE production and are particularly involved in eosinophilic inflammation, allergy and clearance of helminthic infections. A third member of the T helper set, IL-17-producing CD4(+) T cells, now called Th17 cells, was recently described as a distinct lineage that does not share developmental pathways with either Th1 or Th2 cells. the Th17 subset has been linked to autoimmune disorders, being able to produce IL-17, IL-17F and IL-21 among other inflammatory cytokines. Interestingly, it has been reported that there is not only a cross-regulation among Th1, Th2 and Th17 effector cells but there is also a dichotomy in the generation of Th17 and T regulatory cells. Therefore, Treg and Th17 effector cells arise in a mutually exclusive fashion, depending on whether they are activated in the presence of TGF-beta or TGF-beta plus inflammatory cytokines such as IL-6. This review will address the discovery of the Th17 cells, and recent progress on their development and regulation.Crohn's and Colitis Foundation of AmericaNIHLa Jolla Inst Allergy & Immunol, La Jolla, CA 92037 USAUniversidade Federal de São Paulo, Dept Microbiol Immunol & Parasitol, São Paulo, BrazilUniversidade Federal de São Paulo, Dept Microbiol Immunol & Parasitol, São Paulo, BrazilNIH: RO1 AI050265-06Web of Scienc
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