745 research outputs found
In vitro and in vivo models of acute alcohol exposure
Alcohol abuse is a global problem due to the financial burden on society and the healthcare system. While the harmful health effects of chronic alcohol abuse are well established, more recent data suggest that acute alcohol consumption also affects human wellbeing. Thus, there is a need for research models in order to fully understand the effect of acute alcohol abuse on different body systems and organs. The present manuscript summarizes the interdisciplinary advantages and disadvantages of currently available human and non-human models of acute alcohol abuse, and identifies their suitability for biomedical research
Inequalities in Human Well-Being in the Urban Ganges Brahmaputra Meghna Delta
The recently endorsed Sustainable Development Goals (SDGs) agenda unanimously agrees
on the need to focus on inclusive development, the importance of eradicating extreme poverty and
managing often complex human well-being impacts of rapid urban growth. Sustainable and inclusive
urbanisation will accelerate progress towards the SDGs and contribute to eradicating extreme poverty.
In tropical delta regions, such as the Ganges Brahmaputra Meghna delta region, urban growth
and resulting intra-urban inequalities are accelerated by the impact of environmental and climate
change. In this context, the present study uses the 2010 Household Income and Expenditure Survey
to analyse the extent of wealth-based inequalities in human well-being in the urban delta region and
the determinants of selected welfare measures. The results suggest that the extent of intra-urban
inequalities is greatest in educational attainment and access to postnatal healthcare and relatively
low in the occurrence of gastric disease. The paper concludes by providing policy recommendations
to reduce increasing wealth inequalities in urban areas, thus contributing to sustainable development
of the region
Distinct Toll-like receptor expression in monocytes and T cells in chronic HCV infection
AIM: Hepatitis C virus often establishes chronic infections. Recent studies suggest that viral and bacterial infections are more common in HCV-infected patients compared to controls. Pathogens are recognized by Toll-like receptors (TLRs) to shape adaptive and innate immune responses.
METHODS: In this study, to assess the ability of HCV-infected host to recognize invading pathogens, we investigated Toll-like receptor expression in innate (monocytes) and adaptive (T cells) immune cells by real-time PCR.
RESULTS: We determined that RNA levels for TLRs 2, 6. 7, 8, 9 and 10 mRNA levels were upregulated in both monocytes and T cells in HCV-infected patients compared to controls. TLR4 was only upregulated in T lymphocytes, while TLR5 was selectively increased in monocytes of HCV-infected patients. MD-2, a TLR4 co-receptor, was increased in patients\u27 monocytes and T cells while CD14 and MyD88 were increased only in monocytes.
CONCLUSION: Our data reveal novel details on TLR expression that likely relates to innate recognition of pathogens and immune defense in HCV-infected individuals
Direct binding of cytosolic NDP kinases to membrane lipids is regulated by nucleotides
AbstractIn spite of their complete lack of any structural features that characterize membrane proteins, cytosolic nucleoside-diphosphate kinases (NDPKs) have been found repeatedly to associate with membranes. In some instances the recruitment of cytosolic NDPKs to membranes was attributed to interactions with peripheral or integral membrane proteins, but in many cases the mechanism underlying the association of NDPKs with membranes remained unknown. We show here that cytosolic NDPKs bind directly to membrane lipids in a dynamic process that is controlled by its substrates, nucleoside tri- and diphosphates, and can be fully reconstituted with chemically defined, protein-free phospholipids and recombinant NDPK, or with purified NDPK. Our results uncover a novel mechanism for the reversible targeting of soluble NDPKs to membranes, where they may act as a reservoir of high energy phosphate, supporting the operation of membrane-based processes that utilize nucleotides other than ATP, such as intracellular traffic and phospholipid biosynthesis
Methods for the Isolation of Sensory and Primary Cilia—An Overview
Detailed proteomic analyses of mammalian olfactory and rod photoreceptor sensory cilia are now available, providing an inventory of resident ciliary proteins and laying the foundation for future studies of developmental and spatio-temporal changes in the composition of sensory cilia. Cilia purification methods that were elaborated and perfected over several decades were essential for these advances. In contrast, the proteome of primary cilia is yet to be established, because purification procedures for this organelle have been developed only recently. In this chapter we review current techniques for the purification of olfactory and photoreceptor cilia, and evaluate methods designed for the selective isolation of primary cilia
Receptor Activation Regulates Cortical, but not Vesicular Localization of NDP Kinase
We used immunofluorescence techniques to determine the localization of nucleoside diphosphate (NDP) kinase in NIH-3T3 fibroblasts. We found that cytoplasmic NDP kinase can be separated into two populations according to subcellular localization and response to extracellular stimuli. Specifically, within minutes of stimulation of resting fibroblasts with serum, growth factors or bombesin, a portion of NDP kinase becomes associated with membrane ruffles and lamellipodia. Another pool of NDP kinase accumulates independently of stimulation around intracellular vesicles. Transfection of cells with activated Rac mimics, whereas expression of dominant negative Rac inhibits, the effects of extracellular stimulation on the translocation of NDP kinase to the cell cortex. Neither Rac mutant affects the vesicle-associated pool. Association of NDP kinase with vesicles depends on microtubule integrity and is disrupted by nocodazole. In cell-free assays NDP kinase binds tightly to membrane vesicles associated with taxol-stabilized microtubules. Binding of NDP kinase to this fraction is reduced by ATP and abolished by GTP, as well as guanine nucleotides that are NDP kinase substrates. Thus, the localization of the two NDP kinase pools identified here is regulated independently by distinct cellular components: the appearance of cortical NDP kinase is a consequence of Rac activation, whereas vesicular NDP kinase is responsive to microtubule dynamics and nucleotides, in particular GTP. These results suggest that in fibroblasts NDP kinase participates in Racrelated cortical events and in GTP-dependent processes linked to intracellular vesicle trafficking
NDP Kinase Moves into Developing Primary Cilia
Inmunofluorescence staining of murine NIH3T3 fibroblasts grown at high density shows that conventional nucleoside diphosphate (NDP) kinases A and B localize to a sensory organelle, the primary cilium. Similar results are obtained with Xenopus A6 kidney epithelial cells, suggesting that NDP kinases are a universal component of the primary cilium. The translocation of NDP kinase into primary cilia depends on size, taking place only when cilia reach a critical length of 5-6 μm. In mature cilia, NDP kinases are distributed along the ciliary shaft in a punctate pattern that is distinct from the continuous staining observed with acetylated α-tubulin, a ciliary marker and axonemal component. Isolation of a fraction enriched in primary cilia from A6 cells led to the finding that ciliary NDP kinase is enzymatically active, and is associated with the membrane and the matrix, but not the axoneme. In contrast, acetylated α-tubulin is found in the axoneme and to a lesser extent, in the membrane. Based on the tightly regulated translocation process and the subciliary distribution pattern of NDP kinase, we propose that it plays a role in the elongation and maintenance of primary cilia by its ability to regenerate the GTP utilized by ciliary microtubule turnover and transmembrane signaling
Increased oxidative capacity of circulating polymorphonuclear neutrophils (PMNs) in non-diabetic NASH patients
Background: Inflammation and oxidative stress are key factors in the pathogenesis of non-alcoholic steatohepatitis (NASH). Polymorphonuclear neutrophils are capable to produce significant amounts of reactive oxygen species (ROS) via the NADPH oxidase complex. Increased hepatic neutrophil infiltration has been described in steatohepatitis. We aimed to investigate the in vitro ROS generation by neutrophils of NASH patients and the hepatic NADPH oxidase activity in murine steatohepatitis.
Material and methods: PMNs were isolated from peripheral blood of NASH patients (n=16) and healthy controls (n=16). In vitro ROS production was measured by luminol chemiluminescence after phorbol myristate acetate (PMA) or opsonized zymosan stimulation. Hepatic lipid peroxidation and NADPH oxidase activation were measured in mice fed with methionine-choline-deficient (MCD) or -supplemented (MCS) diets.
Results: PMA activated oxidative burst both in patients and controls. However, ROS production was significantly increased in non-diabetic NASH patients (n=9) compared to controls 30 min after the PMA stimulation. PMNs from NASH patients with diabetes mellitus (n=7) did not have higher ROS production after PMA-stimulation compared to controls. The PMA-induced peak chemiluminescence was significantly higher in the non-diabetic NASH patients compared to controls and diabetic NASH patients. No significant difference was observed without any stimulation and in opsonized zymosan induced chemiluminescence. Consistent with the increased oxidative capacity of PMNs in NASH patients, we found increased hepatic lipid peroxidation, higher expression and activation of the NADPH oxidase complex in MCD-steatohepatitis.
Conclusion: Our finding supports the role of neutrophil oxidative stress in NASH. Our novel data suggests that the increased oxidative capacity of the PMNs it is not only localized to the liver but can have systemic effects and serve as a potential biomarker of NASH
Ocotea nutans (Nees) Mez (Lauraceae): chemical composition, antioxidant capacity and biological properties of essential oil
The present study was undertaken to assess the potential uses of the essential oil obtained from Ocotea nutans (Nees) Mez. The hydrodistilled essential oil from O. nutans leaves was analyzed by gas chromatography-mass spectrometry. Fifty-eight compounds representing 87,29% of the total leaf essential oil components were identified, of which biciclogermacrene(11.41%), germacrene-D (4.89%), bisabolol11-ol(3.73%) and spathulenol (3.71%) were the major compounds. The essential oil from O. nutans were tested for antibacterial activity using the minimum inhibitory concentracion (MIC) method, Artemia salina method, larvicidal activity in Aedes aegypti, and antioxidant capacity.The antioxidant activity measured by the phosphomolybdenum complex and Prussian blue method had positive results. The minimum inhibitory concentration for the microorganisms tested allowed moderate inhibitionfor Enterococcus faecalis(MIC=500 µg/mL). Artemia salina were toxic to the organisms in the study (LC50= 71,70 μg /mL). The essential oil showed remarkable larvicidal activity potencial (LC50= 250 µg/mL). The present results showed that O. nutans essential oil has potential biological uses
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