390 research outputs found
Alterations in the gut microbiome implicate key taxa and metabolic pathways across inflammatory arthritis phenotypes
Musculoskeletal diseases affect up to 20% of adults worldwide. The gut microbiome has been implicated in inflammatory conditions, but large-scale metagenomic evaluations have not yet traced the routes by which immunity in the gut affects inflammatory arthritis. To characterize the community structure and associated functional processes driving gut microbial involvement in arthritis, the Inflammatory Arthritis Microbiome Consortium investigated 440 stool shotgun metagenomes comprising 221 adults diagnosed with rheumatoid arthritis, ankylosing spondylitis, or psoriatic arthritis and 219 healthy controls and individuals with joint pain without an underlying inflammatory cause. Diagnosis explained about 2% of gut taxonomic variability, which is comparable in magnitude to inflammatory bowel disease. We identified several candidate microbes with differential carriage patterns in patients with elevated blood markers for inflammation. Our results confirm and extend previous findings of increased carriage of typically oral and inflammatory taxa and decreased abundance and prevalence of typical gut clades, indicating that distal inflammatory conditions, as well as local conditions, correspond to alterations to the gut microbial composition. We identified several differentially encoded pathways in the gut microbiome of patients with inflammatory arthritis, including changes in vitamin B salvage and biosynthesis and enrichment of iron sequestration. Although several of these changes characteristic of inflammation could have causal roles, we hypothesize that they are mainly positive feedback responses to changes in host physiology and immune homeostasis. By connecting taxonomic alternations to functional alterations, this work expands our understanding of the shifts in the gut ecosystem that occur in response to systemic inflammation during arthritis
Alterations in the gut microbiome implicate key taxa and metabolic pathways across inflammatory arthritis phenotypes
Incidence and predictors of immune reconstitution inflammatory syndrome in a rural area of Mozambique.
There is limited data on the epidemiology of Immune Reconstitution Inflammatory Syndrome (IRIS) in rural sub-Saharan Africa. A prospective observational cohort study was conducted to assess the incidence, clinical characteristics, outcome and predictors of IRIS in rural Mozambique
A database of chlorophyll a in Australian waters
© The Author(s) 2018. Chlorophyll a is the most commonly used indicator of phytoplankton biomass in the marine environment. It is relatively simple and cost effective to measure when compared to phytoplankton abundance and is thus routinely included in many surveys. Here we collate 173, 333 records of chlorophyll a collected since 1965 from Australian waters gathered from researchers on regular coastal monitoring surveys and ocean voyages into a single repository. This dataset includes the chlorophyll a values as measured from samples analysed using spectrophotometry, fluorometry and high performance liquid chromatography (HPLC). The Australian Chlorophyll a database is freely available through the Australian Ocean Data Network portal (https://portal.aodn.org.au/). These data can be used in isolation as an index of phytoplankton biomass or in combination with other data to provide insight into water quality, ecosystem state, and relationships with other trophic levels such as zooplankton or fish
Pdx1 and Ngn3 Overexpression Enhances Pancreatic Differentiation of Mouse ES Cell-Derived Endoderm Population
In order to define the molecular mechanisms regulating the specification and differentiation of pancreatic ÎČ-islet cells, we investigated the effect of upregulating Pdx1 and Ngn3 during the differentiation of the ÎČ-islet-like cells from murine embryonic stem (ES) cell-derived activin induced-endoderm. Induced overexpression of Pdx1 resulted in a significant upregulation of insulin (Ins1 and Ins2), and other pancreas-related genes. To enhance the developmental progression from the pancreatic bud to the formation of the endocrine lineages, we induced the overexpression express of Ngn3 together with Pdx1. This combination dramatically increased the level and timing of maximal Ins1 mRNA expression to approximately 100% of that found in the ÎČTC6 insulinoma cell line. Insulin protein and C-peptide expression was confirmed by immunohistochemistry staining. These inductive effects were restricted to c-kit+ endoderm enriched EB-derived populations suggesting that Pdx1/Ngn3 functions after the specification of pancreatic endoderm. Although insulin secretion was stimulated by various insulin secretagogues, these cells had only limited glucose response. Microarray analysis was used to evaluate the expression of a broad spectrum of pancreatic endocrine cell-related genes as well as genes associated with glucose responses. Taken together, these findings demonstrate the utility of manipulating Pdx1 and Ngn3 expression in a stage-specific manner as an important new strategy for the efficient generation of functionally immature insulin-producing ÎČ-islet cells from ES cells
Medroxyprogesterone improves nocturnal breathing in postmenopausal women with chronic obstructive pulmonary disease
BACKGROUND: Progestins as respiratory stimulants in chronic obstructive pulmonary disease (COPD) have been investigated in males and during wakefulness. However, sleep and gender may influence therapeutic responses. We investigated the effects of a 2-week medroxyprogesterone acetate (MPA) therapy on sleep and nocturnal breathing in postmenopausal women. METHODS: A single-blind placebo-controlled trial was performed in 15 postmenopausal women with moderate to severe COPD. A 12-week trial included 2-week treatment periods with placebo and MPA (60 mg/d/14 days). All patients underwent a polysomnography with monitoring of SaO(2 )and transcutaneous PCO(2 )(tcCO(2)) at baseline, with placebo, with medroxyprogesterone acetate (MPA 60 mg/d/14 days), and three and six weeks after cessation of MPA. RESULTS: Thirteen patients completed the trial. At baseline, the average ± SD of SaO(2 )mean was 90.6 ± 3.2 % and the median of SaO(2 )nadir 84.8 % (interquartile range, IQR 6.1). MPA improved them by 1.7 ± 1.6 %-units (95 % confidence interval (CI) 0.56, 2.8) and by 3.9 %-units (IQR 4.9; 95% CI 0.24, 10.2), respectively. The average of tcCO(2 )median was 6.0 ± 0.9 kPa and decreased with MPA by 0.9 ± 0.5 kPa (95% CI -1.3, -0.54). MPA improved SaO(2 )nadir and tcCO(2 )median also during REM sleep. Three weeks after cessation of MPA, the SaO(2 )mean remained 1.4 ± 1.8 %-units higher than at baseline, the difference being not significant (95% CI -0.03, 2.8). SaO(2 )nadir was 2.7 %-units (IQR 4.9; 95% CI 0.06, 18.7) higher than at baseline. Increases in SaO(2 )mean and SaO(2 )nadir during sleep with MPA were inversely associated with baseline SaO(2 )mean (r = -0.70, p = 0.032) and baseline SaO(2 )nadir (r = -0.77, p = 0.008), respectively. Treatment response in SaO(2 )mean, SaO(2 )nadir and tcCO(2 )levels did not associate with pack-years smoked, age, BMI, spirometric results or sleep variables. CONCLUSION: MPA-induced respiratory improvement in postmenopausal women seems to be consistent and prolonged. The improvement was greater in patients with lower baseline SaO(2 )values. Long-term studies in females are warranted
Sidestream cigarette smoke effects on cardiovascular responses in conscious rats: involvement of oxidative stress in the fourth cerebral ventricle
Background: Cigarette exposure increases brain oxidative stress. The literature showed that increased brain oxidative stress affects cardiovascular regulation. However, no previous study investigated the involvement of brain oxidative stress in animals exposed to cigarette and its relationship with cardiovascular regulation. We aimed to evaluate the effects of central catalase inhibition on baroreflex and cardiovascular responses in rats exposed to sidestream cigarette smoke (SSCS). Methods: We evaluated males Wistar rats (320-370 g), which were implanted with a stainless steel guide cannula into the fourth cerebral ventricle (4th V). Femoral artery and vein were cannulated for mean arterial pressure (MAP) and heart rate (HR) measurement and drug infusion, respectively. Rats were exposed to SSCS during three weeks, 180 minutes, 5 days/week (CO: 100-300 ppm). Baroreflex was tested with a pressor dose of phenylephrine (PHE, 8 mu g/kg, bolus) to induce bradycardic reflex and a depressor dose of sodium nitroprusside (SNP, 50 mu g/kg, bolus) to induce tachycardic reflex. Cardiovascular responses were evaluated before, 5, 15, 30 and 60 minutes after 3-amino-1,2,4-triazole (ATZ, catalase inhibitor, 0.001 g/100 mu L) injection into the 4th V. Results: Central catalase inhibition increased basal HR in the control group during the first 5 minutes. SSCS exposure increased basal HR and attenuated bradycardic peak during the first 15 minutes. Conclusion: We suggest that SSCS exposure affects cardiovascular regulation through its influence on catalase activity.Foundation of Support to Research of Sao Paulo State (Fundacao de Amparo a Pesquisa do Estado de Sao Paulo-FAPESP [07/59127-9
The use of race, ethnicity and ancestry in human genetic research
Post-Human Genome Project progress has enabled a new wave of population genetic research, and intensified controversy over the use of race/ethnicity in this work. At the same time, the development of methods for inferring genetic ancestry offers more empirical means of assigning group labels. Here, we provide a systematic analysis of the use of race/ethnicity and ancestry in current genetic research. We base our analysis on key published recommendations for the use and reporting of race/ethnicity which advise that researchers: explain why the terms/categories were used and how they were measured, carefully define them, and apply them consistently. We studied 170 population genetic research articles from high impact journals, published 2008â2009. A comparative perspective was obtained by aligning study metrics with similar research from articles published 2001â2004. Our analysis indicates a marked improvement in compliance with some of the recommendations/guidelines for the use of race/ethnicity over time, while showing that important shortfalls still remain: no article using âraceâ, âethnicityâ or âancestryâ defined or discussed the meaning of these concepts in context; a third of articles still do not provide a rationale for their use, with those using âancestryâ being the least likely to do so. Further, no article discussed potential socio-ethical implications of the reported research. As such, there remains a clear imperative for highlighting the importance of consistent and comprehensive reporting on human populations to the genetics/genomics community globally, to generate explicit guidelines for the uses of ancestry and genetic ancestry, and importantly, to ensure that guidelines are followed
Noble Metal Nanoparticles for Biosensing Applications
In the last decade the use of nanomaterials has been having a great impact in biosensing. In particular, the unique properties of noble metal nanoparticles have allowed for the development of new biosensing platforms with enhanced capabilities in the specific detection of bioanalytes. Noble metal nanoparticles show unique physicochemical properties (such as ease of functionalization via simple chemistry and high surface-to-volume ratios) that allied with their unique spectral and optical properties have prompted the development of a plethora of biosensing platforms. Additionally, they also provide an additional or enhanced layer of application for commonly used techniques, such as fluorescence, infrared and Raman spectroscopy. Herein we review the use of noble metal nanoparticles for biosensing strategiesâfrom synthesis and functionalization to integration in molecular diagnostics platforms, with special focus on those that have made their way into the diagnostics laboratory
Predictors of immune reconstitution inflammatory syndrome associated with Kaposiâs sarcoma: a case report
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