2,488 research outputs found
The Effects of Nutrient Availability on Pseudomonas aeruginosa Mono and Co-culture Biofilms
Cystic Fibrosis (CF) is a genetic disorder characterized by faulty ion channels and result in thick mucus accumulation, especially in lungs. Mucus buildup provides ideal conditions for bacterial infections. Pseudomonas aeruginosa (PA) is the second most prevalent bacterium isolated from people with CF and has a high clinical importance. Most CF pathogens form biofilms which make treatment of infections difficult. Biofilms are clusters of cells attached to a surface enclosed in a structured matrix. These structures are a means to provide shelter for bacteria from the environment, especially antibiotics and the immune system. PA alone can form these biofilms, but communities of different bacterial species can also form biofilms together. Multispecies biofilms can form beneficial or antagonistic relationships with PA. In this study, we investigated the interaction between PA and two other important CF pathogens, Staphylococcus aureus (SA) and Burkholderia cenocepacia (BC). SA is the most prevalent CF pathogen and BC is arguably the most fatal. We tested the survival of these species in groups or alone in various nutrient conditions and in differing tobramycin concentrations. We chose tobramycin because it is an antibiotic commonly prescribed to treat PA infections. Our results show that nutrient composition, antibiotic concentration, and time all had a significant effect on the interactions between PA mono-culture and co-cultured biofilms. Understanding these interactions may set the stage for a better understanding of the clinical course of infection and how treatments can be altered for multi-species infections.https://ir.library.louisville.edu/uars/1017/thumbnail.jp
Galectin-1, an Endogenous Lectin Produced by Thymic Epithelial Cells, Induces Apoptosis of Human Thymocytes
Galectin-1, a ÎČ-galactoside binding protein, is produced by thymic epithelial cells and binds to human thymocytes. We have previously reported that galectin-1 induces the apoptosis of activated T lymphocytes. Because the majority of thymocytes die via apoptosis while still within the thymus, we tested whether galectin-1 could induce the apoptosis of these cells. We now report that in vitro exposure to galectin-1 induced apoptosis of two subsets of CD4lo CD8lo thymocytes. The phenotypes of susceptible thymocytes were consistent with that of both negatively selected and nonselected cells. Galectin-1âinduced apoptosis was enhanced by preexposure of thymocytes to antibody to CD3, suggesting that galectin-1 may be a participant in T-cellâ receptor mediated apoptosis. In contrast, pretreatment of thymocytes with dexamethasone had no effect on galectin-1 susceptibility. We noted that 71% of the cells undergoing apoptosis after galectin-1 treatment had a DNA content greater than 2N, indicating that proliferating thymocytes were most sensitive to galectin-1. We propose that galectin-1 plays a role in the apoptosis of both negatively selected and nonselected thymocytes, and that the susceptibility of thymocytes to galectin-1 is regulated, in part, by entry or exit from the cell cycle
The volume and monetary value of human milk produced by the world's breastfeeding mothers: Results from a new tool
The Mothers' Milk Tool was developed to make more visible the economic value contributed to society by women's unpaid care work through breastfeeding infants and young children. This manuscript describes the development and display key features of the tool, and reports results for selected countries. For the development, we used five steps: (1) defining the tool by reviewing existing tools and scholarly literature to identify uses, approaches, design features, and required data characteristics for a suitable product; (2) specifying the best open-access data available for measurement and easy updating; (3) analyzing development options; (4) testing predictive models to fill identified breastfeeding data gaps; and (5) validating the tool with prospective users and against previous research. We developed an Excel-based tool that allows working offline, displaying preloaded data, imputing data, and inputting users' data. It calculates annual quantities of milk produced by breastfeeding women for children aged 0â35.9 months, and the quantities lost compared to a defined biologically feasible level. It supports calculations for an individual mother, for countries, and global level. Breastfeeding women globally produce around 35.6 billion liters of milk annually, but 38.2% is currently âlostâ due to cultural barriers and structural impediments to breastfeeding. The tool can also attribute a monetary value to the production. In conclusion, the Mothers' Milk Tool shows what is at risk economically if women's important capacity for breastfeeding is not protected, promoted, and supported by effective national policies, programs, and investments. The tool is of value to food and health policymakers, public officials, advocates, researchers, national accountants and statisticians, and individual mother/baby dyads, and will assist consideration of breastfeeding in food balance sheets and economic production statistics. The tool supports the 2015 Call to Action by the Global Breastfeeding Collective by facilitating the tracking of progress on breastfeeding targets
Prostate Field Cancerization and Exosomes: Association Between CD9, Early Growth Response 1 and Fatty Acid Synthase
Intracapsular and wellâdefined adenocarcinomas of the prostate are often surrounded by tissue areas that harbor molecular aberrations, including those of genetic, epigenetic and biochemical nature. This is known as field cancerization, or a field effect and denotes a state of preâmalignancy. Such alterations in histologically normal tumorâadjacent prostatic tissues have been recognized as clinically important and are potentially exploitable as biomarkers of disease and/or targets for preventative/therapeutic intervention. The authors have previously identified and validated two protein markers of field cancerization: The expressional upregulation of the transcription factor early growth response 1 (EGRâ1) and the lipogenic enzyme fatty acid synthase (FASN). However, the molecular etiology of prostate field cancerization, including EGRâ1 and FASN upregulation, remains largely unknown. It was thus hypothesized that extracellular vesicles, notably exosomes, released by tumor lesions may induce molecular alterations in the surrounding tissues, resulting in field cancerization, priming the tissue, and ultimately promoting multifocal tumorigenesis, which is often observed in prostate cancer. Towards testing this hypothesis, the current study, to the best of our knowledge, for the first time, presents correlative protein expression data, generated in diseaseâfree, tumorâadjacent and cancerous human prostate tissues by quantitative immunofluorescence, between the exosomal marker CD9, and EGRâ1 and FASN. Despite the pilot character of the present study, and the static nature and heterogeneity of human tissues, the data suggest that CD9 expression itself is part of a field effect. In support of this hypothesis, the results suggest a possible contribution of exosomes to the induction of field cancerization in the prostate, particularly for EGRâ1. These findings were corroborated in established cell models of cancerous (LNCaP) and nonâcancerous (RWPEâ1) human prostate epithelial cells. The findings of this study warrant further investigation into the functional interface between exosomes and field cancerization, as a detailed understanding of this characterization may lead to the development of clinical applications related to diagnosis and/or prognosis and targeted intervention to prevent progression from preâmalignancy to cancer
Gastro intestinal digestion of dairy and soy proteins in infant formulas: an in vitro study
An in vitro digestion simulating infant gastrointestinal tract studied the digestion of caseins, whey and soy proteins, commonly used in infant formulations, in the presence of proteases only (without lipolytic enzymes). 60 min of gastric phase and 120 min of intestinal phase coupled with gel electrophoresis, confocal microscopy, mastersizer and pH were employed to monitor the degradation of proteins, microstructure, particle size distribution and pH drop of the digesta through the in vitro digestion process. Obtained results showed around 20% of caseins and almost no components of whey were hydrolysed after 60 min in the simulated stomach. In the simulated duodenal phase, 8% of α-lactalbumin was hydrolysed while caseins and ÎČ-lactoglobulin completely digested immediately and 30 min respectively after addition of duodenal digestive proteases. Overall, soy proteins indicated lower level of hydrolysis than dairy proteins during in vitro infant digestion as observed by SDS-PAGE.The soy protein fractions glycinin and ÎČ-conglycinin were partially hydrolysed during the gastrointestinal phase. The observed pH drop confirms that caseins are easily digested in the duodenal phase compared to whey and soy protein. Gastric digestion resulted in a decrease of the particle size of protein aggregates, but no fat coalescence was observed during both gastric and duodenal digestions in the given conditions
Innovative financing for a gender-equitable first-food system to mitigate greenhouse gas impacts of commercial milk formula: investing in breastfeeding as a carbon offset
Womenâs contributions to food production and food security are often overlooked, thus perpetuating inequitable and unsustainable globalized commercial food systems. Womenâs role as producers in the first-food system, breastfeeding, is largely invisible and underfunded, encouraging the production and consumption of environmentally unsustainable commercial milk formula (CMF). This policy brief highlights opportunities for including and funding interventions enabling breastfeeding under carbon offset schemes such as the United Nations Clean Development Mechanism (CDM). A Green Feeding Tool is being developed to account for the national carbon and water footprints of CMF. The tool will help ensure that womenâs contributions to a sustainable first-food system are not ignored by the CDM and other mechanisms funding greenhouse gas emissions reductions
Real-time quantification of microRNAs by stemâloop RTâPCR
A novel microRNA (miRNA) quantification method has been developed using stemâloop RT followed by TaqMan PCR analysis. Stemâloop RT primers are better than conventional ones in terms of RT efficiency and specificity. TaqMan miRNA assays are specific for mature miRNAs and discriminate among related miRNAs that differ by as little as one nucleotide. Furthermore, they are not affected by genomic DNA contamination. Precise quantification is achieved routinely with as little as 25 pg of total RNA for most miRNAs. In fact, the high sensitivity, specificity and precision of this method allows for direct analysis of a single cell without nucleic acid purification. Like standard TaqMan gene expression assays, TaqMan miRNA assays exhibit a dynamic range of seven orders of magnitude. Quantification of five miRNAs in seven mouse tissues showed variation from less than 10 to more than 30â000 copies per cell. This method enables fast, accurate and sensitive miRNA expression profiling and can identify and monitor potential biomarkers specific to tissues or diseases. Stemâloop RTâPCR can be used for the quantification of other small RNA molecules such as short interfering RNAs (siRNAs). Furthermore, the concept of stemâloop RT primer design could be applied in small RNA cloning and multiplex assays for better specificity and efficiency
The Clinical Utility and Specificity of Parent Report of Executive Function among Children with Prenatal Alcohol Exposure
Prenatal alcohol exposure and attention-deficit/hyperactivity disorder (ADHD) result in behavioral issues related to poor executive function (EF). This overlap may hinder clinical identification of alcohol-exposed children. This study examined the relation between parent and neuropsychological measures of EF and whether parent ratings aid in differential diagnosis. Neuropsychological measures of EF, including the Delis-Kaplan Executive Function System (D-KEFS), were administered to four groups of children (8â16 years): alcohol-exposed with ADHD (AE+, n = 80), alcohol-exposed without ADHD (AEâ, n = 36), non-exposed with ADHD (ADHD, n = 93), and controls (CON, n = 167). Primary caregivers completed the Behavior Rating Inventory of Executive Function (BRIEF). For parent ratings, multivariate analyses of variance revealed main effects of Exposure and ADHD and an interaction between these factors, with significant differences between all groups on nearly all BRIEF scales. For neuropsychological measures, results indicated main effects of Exposure and ADHD, but no interaction. Discriminant function analysis indicated the BRIEF accurately classifies groups. These findings confirm compounded behavioral, but not neuropsychological, effects in the AE+ group over the other clinical groups. Parent-report was not correlated with neuropsychological performance in the clinical groups and may provide unique information about neurobehavior. Parent-report measures are clinically useful in predicting alcohol exposure regardless of ADHD. Results contribute to a neurobehavioral profile of prenatal alcohol exposure
Australasian Malignant PLeural Effusion (AMPLE)-3 trial: Study protocol for a multi-centre randomised study comparing indwelling pleural catheter (±talc pleurodesis) versus video-assisted thoracoscopic surgery for management of malignant pleural effusion
Introduction: Malignant pleural effusions (MPEs) are common. MPE causes significant breathlessness and impairs quality of life. Indwelling pleural catheters (IPC) allow ambulatory drainage and reduce hospital days and re-intervention rates when compared to standard talc slurry pleurodesis. Daily drainage accelerates pleurodesis, and talc instillation via the IPC has been proven feasible and safe. Surgical pleurodesis via video-assisted thoracoscopic surgery (VATS) is considered a one-off intervention for MPE and is often recommended to patients who are fit for surgery. The AMPLE-3 trial is the first randomised trial to compare IPC (±talc pleurodesis) and VATS pleurodesis in those who are fit for surgery. Methods and analysis: A multi-centre, open-labelled randomised trial of patients with symptomatic MPE, expected survival of ℠6 months and good performance status randomised 1:1 to either IPC or VATS pleurodesis. Participant randomisation will be minimised for (i) cancer type (mesothelioma vs non-mesothelioma); (ii) previous pleurodesis (vs not); and (iii) trapped lung, if known (vs not). Primary outcome is the need for further ipsilateral pleural interventions over 12 months or until death, if sooner. Secondary outcomes include days in hospital, quality of life (QoL) measures, physical activity levels, safety profile, health economics, adverse events, and survival. The trial will recruit 158 participants who will be followed up for 12 months. Ethics and dissemination: Sir Charles Gairdner and Osborne Park Health Care Group (HREC) has approved the study (reference: RGS356). Results will be published in peer-reviewed journals and presented at scientific meetings. Discussion: Both IPC and VATS are commonly used procedures for MPE. The AMPLE-3 trial will provide data to help define the merits and shortcomings of these procedures and inform future clinical care algorithms. Trial registration: Australia New Zealand Clinical Trial Registry ACTRN12618001013257. Registered on 18 June 2018. Protocol version: Version 3.00/4.02.1
Biological dosimetry after radiosynoviorthesis with rhenium-186 sulphide and erbium-169 citrate
Zur AbschÀtzung der radiobiologischen Sicherheit des Verfahrens wird in dieser Arbeit die Radiosynoviorthese (RSO) mit Re-186 und Er-169 hinsichtlich biologischer Strahleneffekte untersucht.
Bei 23 Patienten wurde eine RSO mit Rhenium-186-Sulfid- (10 Patienten) oder Erbium-169-Zitratkolloid (13 Patienten) durchgefĂŒhrt. Das behandelte Gelenk wurde anschlieĂend ruhig gestellt. Bei allen Patienten erfolgte vor und 17Â19 Tage (Re-186) bzw. 45Â50 Tage (Er-169) nach der RSO eine venöse Blutentnahme. Zur Analyse der Strahlenexposition wurde die HĂ€ufigkeit von dizentrischen Chromosomen in Lymphozyten der ersten Zellteilung in vitro bestimmt. Pro Patient wurden mindestens 1000 Zellen vor und nach der RSO untersucht, was nach lĂ€ngerer Einwirkung niederenergetischer Strahlung ausreichend ist, um im bestrahlten Kollektiv die im Rahmen der RSO erwarteten Strahlendosen nachzuweisen. ErgĂ€nzend wurde bei den mit Re-186 behandelten Patienten der AktivitĂ€tsabtransport aus dem Gelenk mittels Ganzkörperszintigraphie bestimmt.
In der Untersuchung von insgesamt 47017 Zellen fanden sich vor RSO mit Re-186 bzw. Er-169 40 bzw. 88, danach 59 bzw. 105 dizentrische Chromosomen in Lymphozyten des peripheren Blutes. Eine signifikante Zunahme der dizentrischen Chromosomen nach der RSO zeigte sich nicht. Der AktivitÀtsabtransport nach RSO mit Re-186 lag durchschnittlich unter 5 % (unter 3 MBq) und ist damit als gering einzustufen.
Die Ergebnisse der Untersuchung von Chromosomenaberrationen und des AktivitĂ€tsabtransports nach Radiosynoviorthese mit Rhenium-186 und Erbium-169 sprechen fĂŒr eine geringe Strahlenexposition der Patienten und damit fĂŒr die Sicherheit des Verfahrens.The aim of the present studies was to investigate the biological radiation effect of radiosynoviorthesis (RSO) with Re-186 and Er-169 in order to evaluate the safety of this procedure.
RSO with rhenium-186 sulfide colloid (10 patients) or erbium-169 citrate colloid (13 patients) was carried out in a total of 23 patients. Afterwards, the treated joint was immobilised for three days using splints. From all patients, blood was drawn immediately before and 17 to 19 days (Re-186) or 45 to 50 days (Er-169) after RSO. To evaluate the radiation dose, the yield of dicentric chromosomes in lymphocytes was determined exclusively in metaphases of the first cell cycle in vitro. At least 1000 cells per patient have been analysed before and after RSO which is sufficient to find potential radiation effects after long-term exposure to low energy radiation such as to expect after RSO. In addition, for Re-186 the activity leakage from the treated joint was measured by whole-body scintigraphy.
In a total of 47017 cells analysed from 46 blood samples, 40 and 88 before and 59 and 105 dicentrics after RSO with Re-186 and Er-169 were found. This showed no statistically significant increase in the number of dicentric chromosomes. The measured average activity leakage of less than 5 % (less than 3 MBq) was considered to be low.
The results of chromosome analysis and activity measurement after RSO prove that this procedure is associated with a low effective dose in treated patients and thus can be considered a safe treatment
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