2,048 research outputs found
The Dynamics of Germinal Centre Selection as Measured by Graph-Theoretical Analysis of Mutational Lineage Trees
We have developed a rigorous graph-theoretical algorithm for quantifying the shape properties of mutational lineage trees. We show that information about the dynamics of hypermutation and antigen-driven clonal selection during the humoral immune response is contained in the shape of mutational lineage trees deduced from the responding clones. Age and tissue related differences in the selection process can be studied using this method. Thus, tree shape analysis can be used as a means of elucidating humoral immune response dynamics in various situations
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Acupressure to Reduce Treatment-Related Symptoms for Children With Cancer and Recipients of Hematopoietic Stem Cell Transplant: Protocol for a Randomized Controlled Trial.
BackgroundWe describe the study design and protocol of a pragmatic randomized controlled trial (RCT) Acupressure for Children in Treatment for a Childhood Cancer (ACT-CC).ObjectiveTo describe the feasibility and effectiveness of an acupressure intervention to decrease treatment-related symptoms in children in treatment for cancer or recipients of a chemotherapy-based hematopoietic stem cell transplant (HSCT).DesignTwo-armed RCTs with enrollment of 5 to 30 study days.SettingTwo pediatric teaching hospitals.PatientsEighty-five children receiving cancer treatment or a chemotherapy-based HSCT each with 1 parent or caregiver.InterventionPatients are randomized 1:1 to receive either usual care plus daily professional acupressure and caregiver delivered acupressure versus usual care alone for symptom management. Participants receive up to 20 professional treatments.Main outcomeA composite nausea/vomiting measure for the child.Secondary outcomesChild's nausea, vomiting, pain, fatigue, depression, anxiety, and positive affect.Parent outcomesDepression, anxiety, posttraumatic stress symptoms, caregiver self-efficacy, and positive affect. Feasibility of delivering the semistandardized intervention will be described. Linear mixed models will be used to compare outcomes between arms in children and parents, allowing for variability in diagnosis, treatment, and age.DiscussionTrial results could help childhood cancer and HSCT treatment centers decide about the regular inclusion of trained acupressure providers to support symptom management
Hypertension and Cognitive Health Among Older Adults in India
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/156445/2/jgs16741.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/156445/1/jgs16741_am.pd
Is There Less Access to Quality Grocery Stores in Minority and Poor Neighborhoods in Houston, Texas?
Purpose: There has been an enormous increase in obesity and diet-related diseases in the past decade. Limited access to nutritious foods and easier access to unhealthy foods is believed to be among those at fault. However, access to healthy foods, although studied extensively, does not have a standard measure and is conceptualized in multiple ways by researchers. The relationships between availability of quality grocery store and the socio-demographic profile of the neighborhood are not well understood, particularly in an ethnically and socially diverse city, such as Houston. Our study aims to explore the relationships between distribution of small, medium or large grocery stores and community socio-demographics in neighborhoods. Methods: Data on grocery stores characteristics were obtained through InfoUSA. Sales volume and number of employees were used to categorize stores into three types, small, medium and large. Number of stores by type was calculated to the level of neighborhood. Census 2000 data were aggregated for each neighborhood on ethnic composition and poverty. Three ethnic quintile variables were further derived (White, Black, Hispanic) as well as three poverty quintile variables (below poverty level, 1-2 times the poverty level, above twice poverty level). Poisson models by store type were employed to estimate effects of these quintile variables on number of grocery stores. Results: Among the 88 neighborhoods, 12.5% (11) had no small stores, 31.8% (28) no medium stores and 46.6% (41) no large stores. Seven (8%) neighborhoods had no stores of any type. The regression models showed one quintile increment on poverty would result in 1.44 times increase the number of small stores. One quintile increment in ethnic black would reduce the number of medium stores by 14% while “below poverty level” remained positive (1.34 times). Finally, increment of one quintile in ethnic black would reduce the number of large stores by 23%. Conclusions: Our study indicates that there exists significant disparity in access to grocery stores in Houston. Some communities had access to all three types of stores but others had none. We also found higher concentration of small and medium stores in communities of poor people and fewer medium and large stores in communities of more ethnic blacks. These results suggest that impoverished Black communities in Houston may suffer reduced access to a selection of healthy foods when compared to other neighborhoods
Immunoglobulin variable-region gene mutational lineage tree analysis: application to autoimmune diseases
Lineage trees have frequently been drawn to illustrate diversification, via somatic hypermutation (SHM), of immunoglobulin variable-region (IGV) genes. In order to extract more information from IGV sequences, we developed a novel mathematical method for analyzing the graphical properties of IgV gene lineage trees, allowing quantification of the differences between the dynamics of SHM and antigen-driven selection in different lymphoid tissues, species, and disease situations. Here, we investigated trees generated from published IGV sequence data from B cell clones participating in autoimmune responses in patients with Myasthenia Gravis (MG), Rheumatoid Arthritis (RA), and Sjögren's Syndrome (SS). At present, as no standards exist for cell sampling and sequence extraction methods, data obtained by different research groups from two studies of the same disease often vary considerably. Nevertheless, based on comparisons of data groups within individual studies, we show here that lineage trees from different individual patients are often similar and can be grouped together, as can trees from two different tissues in the same patient, and even from IgG- and IgA-expressing B cell clones. Additionally, lineage trees from most studies reflect the chronic character of autoimmune diseases
Revitalizing Civic Engagement through Collaborative Governance: Stories of Success From Around the United States
A growing level of political dysfunction and hyper-partisan polarization has led us to a critical point in the way we govern. With democracy under threat and deep distrust of democratic institutions, how can we instill innovative reforms centered around real influence and decision-making power? At a moment of extreme vulnerability, communities and civic organizations need to have genuine political agency by directly influencing policy decision-making. Collaborative governance—or "co-governance"—offers an opportunity to create new forms of civic power. This report offers lessons from across local, city, state, and federal policymaking and highlights effective models of co-governance from community leaders and those in government
A retrospective cohort study measured predicting and validating the impact of the COVID-19 pandemic in individuals with chronic kidney disease
Chronic kidney disease (CKD) is associated with increased risk of baseline mortality and severe COVID-19, but analyses across CKD stages, and comorbidities are lacking. In prevalent and incident CKD, we investigated comorbidities, baseline risk, COVID-19 incidence, and predicted versus observed one-year excess death. In a national dataset (NHS Digital Trusted Research Environment (NHSD TRE)) for England encompassing 56 million individuals), we conducted a retrospective cohort study (March 2020 to March 2021) for prevalence of comorbidities by incident and prevalent CKD, SARS-CoV-2 infection and mortality. Baseline mortality risk, incidence and outcome of infection by comorbidities, controlling for age, sex and vaccination were assessed. Observed versus predicted one-year mortality at varying population infection rates and pandemic-related relative risks using our published model in pre-pandemic CKD cohorts (NHSD TRE and Clinical Practice Research Datalink (CPRD)) were compared. Among individuals with CKD (prevalent:1,934,585, incident:144,969), comorbidities were common (73.5% and 71.2% with one or more condition(s) in respective data sets, and 13.2% and 11.2% with three or more conditions, in prevalent and incident CKD), and associated with SARS-CoV-2 infection, particularly dialysis/transplantation (odds ratio 2.08, 95% confidence interval 2.04-2.13) and heart failure(1.73, 1.71-1.76), but not cancer (1.01, 1.01-1.04). One-year all-cause mortality varied by age, sex, multi-morbidity and CKD stage. Compared with 34,265 observed excess deaths, in the NHSD-TRE and CPRD databases respectively, we predicted 28,746 and 24,546 deaths (infection rates 10% and relative risks 3.0), and 23,754 and 20,283 deaths (observed infection rates 6.7% and relative risks 3.7). Thus, in this largest, national-level study, individuals with CKD have a high burden of comorbidities and multi-morbidity, and high risk of pre-pandemic and pandemic mortality. Hence, treatment of comorbidities, non-pharmaceutical measures, and vaccination are priorities for people with CKD and management of long-term conditions is important during and beyond the pandemic
The Prevalence of Cognitive Impairment Among Adults With Incident Heart Failure: The “Reasons for Geographic and Racial Differences in Stroke” (REGARDS) Study
Background
Cognitive impairment (CI) is estimated to be present in 25%–80% of heart failure (HF) patients, but its prevalence at diagnosis is unclear. To improve our understanding of cognition in HF, we determined the prevalence of CI among adults with incident HF in the REGARDS study.
Methods and Results
REGARDS is a longitudinal cohort study of adults ≥45 years of age recruited in the years 2003–2007. Incident HF was expert adjudicated. Cognitive function was assessed with the Six-Item Screener. The prevalence of CI among those with incident HF was compared with the prevalence of CI among an age-, sex-, and race-matched cohort without HF. The 436 participants with incident HF had a mean age of 70.3 years (SD 8.9), 47% were female, and 39% were black. Old age, black race, female sex, less education, and anticoagulation use were associated with CI. The prevalence of CI among participants with incident HF (14.9% [95% CI 11.7%–18.6%]) was similar to the non-HF matched cohort (13.4% [11.6%–15.4%]; P < .43).
Conclusions
A total of 14.9% of the adults with incident HF had CI, suggesting that the majority of cognitive decline occurs after HF diagnosis. Increased awareness of CI among newly diagnosed patients and ways to mitigate it in the context of HF management are warranted
Mechanisms of immunosenescence
On April 7,8, 2009 a Symposium entitled "Pathophysiology of Successful and Unsuccessful Ageing" took place in Palermo, Italy. Here, the lectures of G. Pawelec, D. Dunn-Walters and. G. Colonna-Romano on T and B immunosenescence are summarized. In the elderly, many alterations of both innate and acquired immunity have been described. Alterations to the immune system in the older person are generally viewed as a deterioration of immunity, leading to the use of the catch-all term immunosenescence. Indeed, many immunological parameters are often markedly different in elderly compared to young people, and some, mostly circumstantial, evidence suggests that retained function of both innate and acquired immunity in the elderly is correlated with health status. What is often not clear from studies is how far immune dysfunction is a cause or an effect. A better understanding of immunosenescence and mechanisms responsible for proven deleterious changes is needed to maintain a healthy state in later life and to design possible therapeutic interventions
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