246 research outputs found

    Bartonella Clarridgeiae: Invasion of Human Microvascular Endothelial Cells and Role of Flagella in Virulence

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    B. henselae, B. bacilliformis and B. quintana are capable of causing vasoproliferative diseases in humans by modulating apoptosis and proliferation of endothelial cells. Bartonella clarridgeiae, a close relative of the pathogenic Bartonellae, has been implicated in human disease but has not yet been isolated from a human patient. Both B. bacilliformis and B. clarridgeiae have flagella and a flagellar type 3 secretion system, while B. henselae and B. quintana do not. We created 2 non-motile mutants of B. clarridgeiae by interrupting the flagellin gene, flaA, or the flagellar motor genes, motBC. We investigated whether B. clarridgeiae could invade human endothelial cells (HMECs) and if functional flagella were important for invasion. The non-motile mutants and the wild-type strain were capable of entering HMECs in vitro. The flaA mutant was deficient in attachment, but the HMECs in culture with the flaA mutant demonstrated increased proliferation. The motBC mutant showed enhanced invasion. Differential secretion of proteins was revealed by 2-D electrophoresis and MALDI-TOF analysis of secretomes from the co-cultures compared to uninfected HMECs. HMECS infected with wild-type B. clarridgeiae secreted proteins indicative of proliferation. The flaA mutant induced the secretion of proteins involved in cytoskeletal rearrangement, cell migration, and proliferation. The motBC-infected HMECs showed signs of hypoxia. The co-chaperonin GroES was found in higher concentration in the supernatant of the hyper-invasive motBC strain/HMEC co-culture than the wild-type co-culture and was found at a very low concentration in the flaA culture supernatant. Cross-talk between secretion systems is suggested

    Re-thinking Personal Narrative in the Pedagogy of Writing Teacher Preparation

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    How can teacher educators mobilize contemporary understandings of personal narrative -- as socially and dialogically shaped in the context of culture and as instrumental to sociocultural processes of self-authoring -- in the teaching of narrative writing and, more specifically, in the work of teaching teachers to teach narrative writing? Rarely do teachers teach strategies that might result in good narratives. Rarely do narrative texts written in school (or any other kinds of texts written in school, for that matter) actually go anywhere beyond the teacher, thus failing to offer students experience in negotiating meanings with readers, working out the versions of self in context that narrative writing can foster. Teaching personal narrative well, in ways that are consistent with a social and dialogic view of personal narrative’s value and the identity work it can support, has proven challenging. This essay describes and reflects on one effort to do so in a teacher education setting. We introduce the example of a class-to-class partnership between teacher candidates and first-year college writers not as a success story or an exemplar, but rather as a problematic case to stimulate conversation about the challenges of narrative writing teacher preparation

    Impact of education and training on type of care provided by community-based breastfeeding counselors: a cross-sectional study

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    <p>Abstract</p> <p>Background</p> <p>Studies using community-based breastfeeding counselors (CBBCs) have repeatedly shown positive impact on breastfeeding initiation, exclusivity and duration, particularly among low-income mothers. To date, there has not been a comprehensive study to determine the impact of CBBC attributes such as educational background and training, on the type of care that CBBCs provide.</p> <p>Methods</p> <p>This was a cross-sectional study of a convenience sample of CBBCs to ascertain the influence of counselor education and type of training on type of support and proficiency of CBBCs in communities across the United States. Invitations to participate in this online survey of CBBCs were e-mailed to program coordinators of the Special Supplemental Nutrition Program for Women, Infants, and Children (WIC), La Leche League, and other community-based health organizations, who in turn invited and encouraged their CBBCs to participate. Descriptive analysis was used to describe participants (N = 847), while bivariate analysis using χ<sup>2 </sup>test was used to examine the differences between CBBC education, training received and breastfeeding support skills used. Multivariate logistic regression was used to assess the independent determinants of specific breastfeeding support skills.</p> <p>Results</p> <p>The major findings from the research indicate that overall, educational attainment of CBBCs is not a significant predictor for the curriculum used in their training and type of support skills used during counseling sessions, but initial training duration was positively associated with the use of many breastfeeding support skills. Another major influence of counselor support to clients is the type of continuing education they receive after their initial training, with higher likelihood of use of desirable support skills associated with counselors continuing their breastfeeding education at conferences or trainings away from their job sites.</p> <p>Conclusions</p> <p>Our results show that different programs use different training curricula to train their CBBCs varying in duration and content. Counselor education is not a significant predictor of the type of training they receive. Continuing breastfeeding education is a significant determinant of type of counseling techniques used with clients. Further research is therefore needed to critically examine the content of the various training curricula of CBBC programs. This may show a need for a standardized training curriculum for all CBBC programs worldwide to make CBBCs more proficient and efficient, ensuring successful and optimum breastfeeding experiences for mothers and their newborns.</p

    Addressing post-harvest losses during traditional banana fermentation for increased food security in Southwest Uganda

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    Postharvest losses (PHL) destroy 20-60% of the food production in East Africa, exacerbating already severe regional food insecurity. Fermenting perishable foods such as fruits may reduce PHL while providing nutritional enrichment, improving shelf-life and food quality, and addressing seasonality in food supply. Fermented banana products have been refined and diversified in Uganda over generations to make the greatest use of available food resources, but still parts of the raw material are being lost during processing. This study aimed at exploring existing traditional methods and efficiency of fermentation of Musa (AAA-EAHB) 'Mbidde' in southwestern Uganda. The study gathered information through participatory explorations (working with brewers) on banana juice (lightly fermented beer with <1% alcohol content [n=20 brewers]), tonto (turbid beer with ~4% alcohol [n=20]), and amarwa (smoky spirit with ~ 40% alcohol [n=20]). Brewers mentioned several losses of material during harvest and processing. Harvesting bananas requires felling the plant causing ripe fruit damage, particularly during harvest for processing banana juice (loss from fresh bananas=6.4%±8.8%) or amarwa (loss=9.3%±9.5%). Second, losses occur when brewers squeeze juice from the raw banana pulp using stems of Imperata cylindrica, which is then discarded or fed to animals together with the adherent fruit pulp (losses from raw banana juice=50.6%±0.2%; from tonto 39.2%±21.4% and amarwa 47.6%±12.5%). Other causes of PHL during processing are excessive peeling for tonto processing (loss of banana flesh=18.6%±5.8%) and losses of intermediate products during distillation of amarwa (loss=75.9%±1.3%). Total losses of banana products during processing were rare and caused by sabotage (mostly by children), mistakes in the brewing process (e.g. addition of too much water), using bananas of wrong ripening stage, and equipment failure (e.g., burst or leaking drums in distillation equipment). Other non-PHL challenges include Banana Xanthomonas Wilt (BXW) and bad weather (up to 50% losses in the field). Despite the general efficiency of traditional fermentation practices, significant portions of fruit are still lost. Reduction in PHL can complement, both culturally and nutritionally, the role that fermented banana products play in Ugandan food systems and contribute to regional food security. Collaborative mechanisms for PHL reduction should target the cited sources of PHL

    Use of Gastric Bypass Surgery for the Treatment of Type 2 Diabetes Mellitus

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    Over the past decade, the incidence of type 2 diabetes mellitus (T2DM) has increased significantly. Evidence has shown that a clear association exists between obesity and diabetes development. This association has inspired researchers to explore bariatric surgery as an option for diabetes management and possible disease reversal. Improvement of T2DM using Roux-En-Y gastric bypass (RYGB) is thought to result from from a combination of weight loss, decreased caloric intake, hormonal changes and rearrangement of the gastrointestinal anatomy. Positive outcomes resulting from the procedure include decreased mortality rates, normalization of HbA1c levels, decreased dependence on diabetic medications, and increased insulin sensitivity. Gastric bypass, specifically RYGB, appears to be a promising treatment for T2DM. Due to possible complications and limited research in some populations, treatment should be restricted to patients with a BMI \u3e 35 with concurrent diabetes. Patients with diabetes who qualify should be counseled on the potential benefits of gastric bypass as a viable option for diabetes management

    Sequencing of 16S rRNA Gene: A Rapid Tool for Identification of Bacillus anthracis

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    In a bioterrorism event, a tool is needed to rapidly differentiate Bacillus anthracis from other closely related spore-forming Bacillus species. During the recent outbreak of bioterrorism-associated anthrax, we sequenced the 16S rRNA generom these species to evaluate the potential of 16S rRNA gene sequencing as a diagnostic tool. We found eight distinct 16S types among all 107 16S rRNA gene seqs fuences that differed from each other at 1 to 8 positions (0.06% to 0.5%). All 86 B. anthracis had an identical 16S gene sequence, designated type 6; 16S type 10 was seen in all B. thuringiensis strains; six other 16S types were found among the 10 B. cereus strains. This report describes the first demonstration of an exclusive association of a distinct 16S sequence with B. anthracis. Consequently, we were able to rapidly identify suspected isolates and to detect the B. anthracis 16S rRNA gene directly from culture-negative clinical specimens from seven patients with laboratory-confirmed anthrax

    The clinical features of juvenile dermatomyositis: A single-centre inception cohort

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    Introduction: Juvenile Dermatomyositis (JDM), a severe and rare autoimmune disease, is the most common idiopathic inflammatory myopathy in children. We describe the clinical features of a large single-centre cohort.Methods: We studied an inception cohort (0-18 years old) referred for diagnosis to the JDM clinic at The Hospital for Sick Children (SickKids), between January 1989 and September 2017. Probable or definite diagnosis of JDM was done according to the 2017 ACR/EULAR Criteria. We excluded children who had treatment started at another hospital. The data were collected retrospectively from clinical charts and the SickKids JDM database.Results: 172/230 (74.8%) patients were included. They were most often female (female:male = 1.8:1); the age at diagnosis was 8.5 +/- 4.3 years. There was a positive family history for autoimmune disease in 52%, mainly rheumatoid arthritis. No patient died. The most common signs at inception were muscle weakness (85.5%), nailfold capillary abnormalities (83.4%), Gottron papules (78.5%), heliotrope rash (66.3%), abnormal gait (55.8%), and malar/facial rash (54.7%). The prevalence of Gottron papules, heliotrope rash, facial/malar rash, nailfold capillary abnormalities, Raynaud phenomenon, dysphonia/dysphagia (a frequent cause of hospitaliza-tion), mouth ulcers, calcinosis, eye problems, joint involvement, acanthosis nigricans and lipodystrophy increased during follow-up. Muscle enzymes, namely CK, ALT, AST, were often normal or only slightly raised despite active muscle disease; conversely LD was often high. Anti-Nuclear Autoantibodies were positive in 49.7% of patients at diagnosis. The course of the disease was: 29.1% monocyclic, 5.3% polycyclic, 33.1% chronic. The course of 56 patients (32.5%) was not classifiable due to length of follow-up. Corticosteroids were used as treatment in almost all our patients and 30% required intravenous therapy due to the severity of the presen-tation; methotrexate was added in 64%, more often in recent years. Unresponsive patients were treated mostly with intravenous immunoglobulins (IVIG).Conclusions: The information obtained from this relatively large number of patients adds to the growing knowledge base of this rare disease. Trial registration: SickKids Research Ethics Board approved the study

    Spitzer IRAC observations of newly-discovered planetary nebulae from the Macquarie-AAO-Strasbourg H-alpha Planetary Nebula Project

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    We compare H-alpha, radio continuum, and Spitzer Space Telescope (SST) images of 58 planetary nebulae (PNe) recently discovered by the Macquarie-AAO-Strasbo- urg H-alpha PN Project (MASH) of the SuperCOSMOS H-alpha Survey. Using InfraRed Array Camera (IRAC) data we define the IR colors of PNe and demonstrate good isolation between these colors and those of many other types of astronomical object. The only substantive contamination of PNe in the color-color plane we illustrate is due to YSOs. However, this ambiguity is readily resolved by the unique optical characteristics of PNe and their environs. We also examine the relationships between optical and MIR morphologies from 3.6 to 8.0um and explore the ratio of mid-infrared (MIR) to radio nebular fluxes, which is a valuable discriminant between thermal and nonthermal emission. MASH emphasizes late evolutionary stages of PNe compared with previous catalogs, enabling study of the changes in MIR and radio flux that attend the aging process. Spatially integrated MIR energy distributions were constructed for all MASH PNe observed by the GLIMPSE Legacy Project, using the H-alpha morphologies to establish the dimensions for the calculations of the Midcourse Space Experiment (MSX), IRAC, and radio continuum (from the Molonglo Observatory Synthesis Telescope and the Very Large Array) flux densities. The ratio of IRAC 8.0-um to MSX 8.3-um flux densities provides a measure of the absolute diffuse calibration of IRAC at 8.0 um. We independently confirm the aperture correction factor to be applied to IRAC at 8.0um to align it with the diffuse calibration of MSX. The result agrees with the recommendations of the Spitzer Science Center and with results from a parallel study of HII regions. These PNe probe the diffuse calibration of IRAC on a spatial scale of 9-77 arcsec.Comment: 48 pages, LaTeX (aastex), incl. 18 PostScript (eps) figures and 3 tables. Accepted by Astrophysical Journa

    Core and region-enriched networks of behaviorally regulated genes and the singing genome

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    Songbirds represent an important model organism for elucidating molecular mechanisms that link genes with complex behaviors, in part because they have discrete vocal learning circuits that have parallels with those that mediate human speech. We found that ~10% of the genes in the avian genome were regulated by singing, and we found a striking regional diversity of both basal and singing-induced programs in the four key song nuclei of the zebra finch, a vocal learning songbird. The region-enriched patterns were a result of distinct combinations of region-enriched transcription factors (TFs), their binding motifs, and presinging acetylation of histone 3 at lysine 27 (H3K27ac) enhancer activity in the regulatory regions of the associated genes. RNA interference manipulations validated the role of the calcium-response transcription factor (CaRF) in regulating genes preferentially expressed in specific song nuclei in response to singing. Thus, differential combinatorial binding of a small group of activity-regulated TFs and predefined epigenetic enhancer activity influences the anatomical diversity of behaviorally regulated gene networks

    Cardiac arrhythmia and epilepsy genetic variants in sudden unexpected death in epilepsy

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    IntroductionSudden Unexpected Death in Epilepsy (SUDEP) is the leading epilepsy-related cause of death, affecting approximately 1 per 1,000 individuals with epilepsy per year. Genetic variants that affect autonomic function, such as genes associated with cardiac arrhythmias, may predispose people with epilepsy to greater risk of both sudden cardiac death and SUDEP. Advances in next generation sequencing allow for the exploration of gene variants as potential biomarkers.MethodsGenetic testing for the presence of cardiac arrhythmia and epilepsy gene variants was performed via genetic panels in 39 cases of SUDEP identified via autopsy by the Ontario Forensic Pathology Service. Variants were summarized by in-silico evidence for pathogenicity from 4 algorithms (SIFT, PolyPhen-2, PROVEAN, Mutation Taster) and allele frequencies in the general population (GnomAD). A maximum credible population allele frequency of 0.00004 was calculated based on epilepsy prevalence and SUDEP incidence to assess whether a variant was compatible with a pathogenic interpretation.ResultsMedian age at the time of death was 33.3 years (range: 2, 60). Fifty-nine percent (n=23) were male. Gene panels detected 62 unique variants in 45 genes: 19 on the arrhythmia panel and 26 on the epilepsy panel. At least one variant was identified in 28 (72%) of decedents. Missense mutations comprised 57 (92%) of the observed variants. At least three in silico models predicted 12 (46%) cardiac arrhythmia panel missense variants and 20 (65%) epilepsy panel missense variants were pathogenic. Population allele frequencies were &lt;0.00004 for 11 (42%) of the cardiac variants and 10 (32%) of the epilepsy variants. Together, these metrics identified 13 SUDEP variants of interest.DiscussionNearly three-quarters of decedents in this SUDEP cohort carried variants in comprehensive epilepsy or cardiac arrhythmia gene panels, with more than a third having variants in both panels. The proportion of decedents with cardiac variants aligns with recent studies of the disproportionate cardiac burden the epilepsy community faces compared to the general population and suggests a possible cardiac contribution to epilepsy mortality. These results identified 13 priority targets for future functional studies of these genes potential role in sudden death and demonstrates the necessity for further exploration of potential genetic contributions to SUDEP
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