An antigen-driven B-cell response within the salivary glands of patients with Sjögren’s syndrome

Infection with a bacterium or virus induces the production of antibodies, specialised protein molecules that bind to and eliminate the microorganism. These antibodies are produced by B-cells that are stimulated by antigen (any foreign protein or carbohydrate) in the lymph nodes and spleen. During this process, they diversify their variable region genes (V-genes), encoding the antigen-binding region of the antibody, by switching on machinery that mutates the V-genes at a very high rate (somatic hypermutation). In autoimmune diseases, B-cells produce autoantibodies against self-antigens present on the patient's own tissues. Clusters of B- and T-cells are frequently found in the target organs of autoimmune disease. The aim of the work described here was to determine whether these clusters of cells are responding to stimulation by antigen. For this purpose we investigated the B-cell response in patients with an autoimmune disease affecting the salivary and lachrymal glands. By cloning and sequencing the expressed V-genes from indvidual clusters of cells in the salivary glands, we were able to show that the B-cells in these clusters are undergoing clonal proliferation, somatic hypermutation and antigen selection. The presence of similar structures in the target tissues of other autoimmune diseases suggests that this is a widespread phenomenon

Thyroid hormone therapy for older adults with subclinical hypothyroidism

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The evolutionary sequence of post-starburst galaxies

© 2017 The Authors. There are multiple ways in which to select post-starburst galaxies in the literature. In this work, we present a study into how two well-used selection techniques have consequences on observable post-starburst galaxy parameters, such as colour, morphology and environment, and how this affects interpretations of their role in the galaxy duty cycle. We identify a master sample of Hδ strong (EWHδ> 3Å) post-starburst galaxies from the value-added catalogue in the seventh data release of the Sloan Digital Sky Survey (SDSS DR7) over a redshift range 0.01 -2.5Å) but one having an additional cut onEWHα (> -3Å).We examine the differences in observables and AGN fractions to see what effect the Hα cut has on the properties of post-starburst galaxies and what these differing samples can tell us about the duty cycle of post-starburst galaxies. We find that Hδ strong galaxies peak in the 'blue cloud', E+As in the 'green valley' and pure E+As in the 'red sequence'.We also find that pure E+As have a more early-type morphology and a higher fraction in denser environments compared with the Hδ strong and E+A galaxies. These results suggest that there is an evolutionary sequence in the post-starburst phase from blue discy galaxies with residual star formation to passive red early-types

Antigen-driven clonal proliferation of B cells within the target tissue of an autoimmune disease: the salivary glands of patients with Sjögren's syndrome

Structures resembling germinal centers are seen in the salivary glands of patients with Sjögren's syndrome, but it is not known whether the microenvironment of these cell clusters is sufficient for the induction of a germinal center response. Therefore, we cloned and sequenced rearranged Ig V genes expressed by B cells isolated from sections of labial salivary gland biopsies from two Sjögren's syndrome patients. Rearranged V genes from B cells within one cell cluster were polyclonal and most had few somatic mutations. Two adjacent clusters from another patient each contained one dominant B cell clone expressing hypermutated V genes. None of the rearranged V genes was found in both clusters, suggesting that cells are unable to migrate out into the surrounding tissue and seed new clusters. The ratios of replacement to silent mutations in the framework and complementarity determining regions suggest antigen selection of high-affinity mutants. These results show that an antigen-driven, germinal center-type B cell response is taking place within the salivary glands of Sjögren's syndrome patients. In view of the recent demonstration of a germinal center response within the rheumatoid synovial membrane and the existence of similar structures in the target tissues of other autoimmune. diseases, we propose that germinal center- type responses can be induced in the nonlymphoid target tissues of a variety of autoimmune diseases

Boulder County biomass

Presented at the Can forests meet our energy needs? The future of forest biomass in Colorado conference, February 21, 2008, Colorado State University, Fort Collins, Colorado.Scott Golden is a Resource Specialist in Forestry and Biomass for Boulder County Parks & Open Space. His primary responsibilities with the agency are the biomass program for the County's district heating system, forest health management, and piloting a new program that assists private landowners with biomass disposal and small diameter utilization. He received his formal forestry training at CSU and has been active in private forestry for 18 years. Scott is an active advocate for biomass energy as it relates to sustainable forestry and communities

An antigen-driven B-cell response within the salivary glands of patients with Sjögren’s syndrome

Infection with a bacterium or virus induces the production of antibodies, specialised protein molecules that bind to and eliminate the microorganism. These antibodies are produced by B-cells that are stimulated by antigen (any foreign protein or carbohydrate) in the lymph nodes and spleen. During this process, they diversify their variable region genes (V-genes), encoding the antigen-binding region of the antibody, by switching on machinery that mutates the V-genes at a very high rate (somatic hypermutation). In autoimmune diseases, B-cells produce autoantibodies against self-antigens present on the patient's own tissues. Clusters of B- and T-cells are frequently found in the target organs of autoimmune disease. The aim of the work described here was to determine whether these clusters of cells are responding to stimulation by antigen. For this purpose we investigated the B-cell response in patients with an autoimmune disease affecting the salivary and lachrymal glands. By cloning and sequencing the expressed V-genes from indvidual clusters of cells in the salivary glands, we were able to show that the B-cells in these clusters are undergoing clonal proliferation, somatic hypermutation and antigen selection. The presence of similar structures in the target tissues of other autoimmune diseases suggests that this is a widespread phenomenon

Managing animal health status information in the cattle market

The paper analyses the problem of information in the cattle market, particularly as it relates to the status of animal health, and discusses ways to limit it with the view to improving social surplus. Against this background, it aims to achieve three major objectives. Firstly, it describes the ways of improving the level of information through such schemes as Conventional Warranties and Third Party Certification and the different choices made by sellers and buyers in the presence of these schemes. Secondly, it studies the various ways by which these schemes make an impact on equilibria in different markets (i.e., the pooling market and the premium market), and, consequently, on the social surplus. Thirdly, it identifies the necessary conditions for a third party/public decision-maker to increase social surplus and reduce the negative externality caused by disease by managing and supporting Third Party Certification. The paper shows that product certification and product warranty cannot coexist because product warranty is suboptimal. It also shows that certification, and a possible supporting of certification or animal testing does not necessarily improve the safety of the trade.Asymmetric information, Third-Party certification, Disease Externalities, Livestock Production/Industries,

Risk factors for chest infection in acute stroke: a prospective cohort study

<p><b>Background and Purpose:</b> Pneumonia is a major cause of morbidity and mortality after stroke. We aimed to determine key characteristics that would allow prediction of those patients who are at highest risk for poststroke pneumonia.</p> <p><b>Methods:</b> We studied a series of consecutive patients with acute stroke who were admitted to hospital. Detailed evaluation included the modified National Institutes of Health Stroke Scale; the Abbreviated Mental Test; and measures of swallow, respiratory, and oral health status. Pneumonia was diagnosed by set criteria. Patients were followed up at 3 months after stroke.</p> <p><b>Results:</b> We studied 412 patients, 391 (94.9%) with ischemic stroke and 21 (5.1%) with hemorrhagic stroke; 78 (18.9%) met the study criteria for pneumonia. Subjects who developed pneumonia were older (mean±SD age, 75.9±11.4 vs 64.9±13.9 years), had higher modified National Institutes of Health Stroke Scale scores, a history of chronic obstructive pulmonary disease, lower Abbreviated Mental Test scores, and a higher oral cavity score, and a greater proportion tested positive for bacterial cultures from oral swabs. In binary logistic-regression analysis, independent predictors (P<0.05) of pneumonia were age >65 years, dysarthria or no speech due to aphasia, a modified Rankin Scale score ≥4, an Abbreviated Mental Test score <8, and failure on the water swallow test. The presence of 2 or more of these risk factors carried 90.9% sensitivity and 75.6% specificity for the development of pneumonia.</p> <p><b>Conclusions:</b> Pneumonia after stroke is associated with older age, dysarthria/no speech due to aphasia, severity of poststroke disability, cognitive impairment, and an abnormal water swallow test result. Simple assessment of these variables could be used to identify patients at high risk of developing pneumonia after stroke.</p&gt