Synapsins I and II Are Not Required for Insulin Secretion from Mouse Pancreatic beta-cells

Synapsins are a family of phosphoproteins that modulate the release of neurotransmitters from synaptic vesicles. The release of insulin from pancreatic beta-cells has also been suggested to be regulated by synapsins. In this study, we have utilized a knock out mouse model with general disruptions of the synapsin I and II genes [synapsin double knockout (DKO)]. Stimulation with 20 mM glucose increased insulin secretion 9-fold in both wild-type (WT) and synapsin DKO islets, whereas secretion in the presence of 70 mM K+ and 1mM glucose was significantly enhanced in the synapsin DKO mice compared to WT. Exocytosis in single beta-cells was investigated using patch clamp. The exocytotic response, measured by capacitance measurements and elicited by a depolarization protocol designed to visualize exocytosis of vesicles from the readily releasable pool and from the reserve pool, was of the same size in synapsin DKO and WT beta-cells. The increase in membrane capacitance corresponding to readily releasable pool was approximately 50fF in both genotypes. We next investigated the voltage-dependent Ca2+ influx. In both WT and synapsin DKO beta-cells the Ca2+ current peaked at 0 mV and measured peak current (I-p) and net charge (Q) were of similar magnitude. Finally, ultrastructural data showed no variation in total number of granules (N-v) or number of docked granules (N-s) between the beta-cells from synapsin DKO mice and WT control. We conclude that neither synapsin I nor synapsin II are directly involved in the regulation of glucose-stimulated insulin secretion and Ca-2-dependent exocytosis in mouse pancreatic beta-cells. (Endocrinology 153: 2112-2119, 2012

Genetic- and Lifestyle-dependent Dental Caries Defined by the Acidic Proline-rich Protein Genes PRH1 and PRH2.

Dental caries is a chronic infectious disease that affects billions of people with large individual differences in activity. We investigated whether PRH1 and PRH2 polymorphisms in saliva acidic proline-rich protein (PRP) receptors for indigenous bacteria match and predict individual differences in the development of caries. PRH1 and PRH2 variation and adhesion of indigenous and cariogenic (Streptococcus mutans) model bacteria were measured in 452 12-year-old Swedish children along with traditional risk factors and related to caries at baseline and after 5-years. The children grouped into low-to-moderate and high susceptibility phenotypes for caries based on allelic PRH1, PRH2 variation. The low-to-moderate susceptibility children (P1 and P4a-) experienced caries from eating sugar or bad oral hygiene or infection by S. mutans. The high susceptibility P4a (Db, PIF, PRP12) children had more caries despite receiving extra prevention and irrespective of eating sugar or bad oral hygiene or S. mutans-infection. They instead developed 3.9-fold more caries than P1 children from plaque accumulation in general when treated with orthodontic multibrackets; and had basic PRP polymorphisms and low DMBT1-mediated S. mutans adhesion as additional susceptibility traits. The present findings thus suggest genetic autoimmune-like (P4a) and traditional life style (P1) caries, providing a rationale for individualized oral care

Acquisition of complement fixing antibodies targeting Plasmodium falciparum merozoites in infants and their mothers in Uganda

BackgroundAntibody-mediated complement fixation has previously been associated with protection against malaria in naturally acquired immunity. However, the process of early-life development of complement-fixing antibodies in infants, both in comparison to their respective mothers and to other immune parameters, remains less clear.ResultsWe measured complement-fixing antibodies in newborns and their mothers in a malaria endemic area over 5 years follow-up and found that infants’ complement-fixing antibody levels were highest at birth, decreased until six months, then increased progressively until they were similar to birth at five years. Infants with high levels at birth experienced a faster decay of complement-fixing antibodies but showed similar levels to the low response group of newborns thereafter. No difference was observed in antibody levels between infant cord blood and mothers at delivery. The same result was found when categorized into high and low response groups, indicating placental transfer of antibodies. Complement-fixing antibodies were positively correlated with total schizont-specific IgG and IgM levels in mothers and infants at several time points. At nine months, complement-fixing antibodies were negatively correlated with total B cell frequency and osteopontin concentrations in the infants, while positively correlated with atypical memory B cells and P. falciparum-positive atypical memory B cells.ConclusionThis study indicates that complement-fixing antibodies against P. falciparum merozoites are produced in the mothers and placentally-transferred, and they are acquired in infants over time during the first years of life. Understanding early life immune responses is crucial for developing a functional, long lasting malaria vaccine

Comparison of two doses and two routes of administration of misoprostol after pre-treatment with mifepristone for early pregnancy termination

<p>Abstract</p> <p>Background</p> <p>It is not known whether a 400 μg dose of misoprostol has a similar efficacy as an 800 μg dose when administered sublingually or vaginally 24 hours after 200 mg mifepristone.</p> <p>Methods</p> <p>It is proposed to undertake a placebo-controlled, randomized, non-inferiority trial (3% margin of equivalence) of the two misoprostol doses when administered sublingually or vaginally using factorial design. A total of 3008 pregnant women (< 63 days of gestational age) who request legal termination of pregnancy will be recruited for the trial at 16 clinics in ten countries providing abortion services. Eligible women willing to join the study will be allocated randomly to one of the four treatment groups within each centre. Women in all treatment groups will first receive 200 mg mifepristone, followed 24 hours later by either 400 μg or 800 μg misoprostol, administered either sublingually or vaginally. The dose and route of administration of misoprostol will be blinded to women, each woman receiving four tablets vaginally and four tablets sublingually, two or four of which are 200 μg tablets of misoprostol and the rest are placebo tablets.</p> <p>The four treatment regimens will be compared in terms of: (i) their efficacy to induce complete abortion; (ii) induction-to-abortion interval when possible; (iii) the frequency of side effects; and (iv) women's perceptions. The initial judgment of the outcome of treatment is made at the follow-up visit on day 15 of the study and the final assessment four weeks later. It is estimated that the clinical phase will require 12–14 months for data collection.</p> <p>To compare the two routes and two doses, relative risks (RR) of failure to achieve a complete abortion and failure to terminate pregnancy and the two-sided 95% CIs will be calculated by standard methods, as well as risk differences and two-sided 95% CIs. The latter will be used to test the non-inferiority hypotheses (at 2.5% level of significance) for achieving complete abortion. The factorial structure will be taken into account in the analysis after testing the interaction.</p> <p>Trial registration</p> <p>ISRCTN87811512</p

Transcriptional profiling of breast cancer metastases identifies liver metastasis-selective genes associated with adverse outcome in luminal A primary breast cancer.

The complete molecular basis of the organ-specificity of metastasis is elusive. This study aimed to provide an independent characterization of the transcriptional landscape of breast cancer metastases with the specific objective to identify liver metastasis-selective genes of prognostic importance following primary tumor diagnosis

Global series: Complex regional pain syndrome: abstracts from the International Association for the Study of Pain complex regional pain syndrome SIG virtual symposia 2021

The aim of this IASP complex regional pain syndrome (CRPS) SIG Global Series 2021 was to bring together clinicians including those from developing countries to better understand the clinical presentation of complex regional pain syndrome in countries with less well-published patient populations. The purpose was to learn from each other about the range of treatments, successful outcomes, and challenges experienced. These meeting proceedings comprise abstracts from nine countries that span 4 continents and are summaries of online presentations delivered by speakers representing these countries over the course of 2 symposia. The symposia were attended by a global audience of approximately 360 people. Patients with CRPS were described and treated by clinicians from countries across Asia (Pakistan, Jordan, South Korea, Taiwan, and Singapore), South America (Brazil and Peru), Africa (South Africa), and Europe (Norway). This reflects that CRPS exists across borders, ethnicities, and cultures. These proceedings provide a broader perspective within the international pain community about how we can better understand and treat CRPS across the globe

Helicobacter pylori Adapts to Chronic Infection and Gastric Disease via pH-Responsive BabA-Mediated Adherence

International audienceThe BabA adhesin mediates high-affinity binding of Helicobacter pylori to the ABO blood group antigen-glycosylated gastric mucosa. Here we show that BabA is acid responsive-binding is reduced at low pH and restored by acid neutralization. Acid responsiveness differs among strains; often correlates with different intragastric regions and evolves during chronic infection and disease progression; and depends on pH sensor sequences in BabA and on pH reversible formation of high-affinity binding BabA multimers. We propose that BabA's extraordinary reversible acid responsiveness enables tight mucosal bacterial adherence while also allowing an effective escape from epithelial cells and mucus that are shed into the acidic bactericidal lumen and that bio-selection and changes in BabA binding properties through mutation and recombination with babA-related genes are selected by differences among individuals and by changes in gastric acidity over time. These processes generate diverse H. pylori subpopulations, in which BabA's adaptive evolution contributes to H. pylori persistence and overt gastric disease

Immune cells lacking Y chromosome show dysregulation of autosomal gene expression

Funder: Kjell och Märta Beijers Stiftelse (SE)Funder: Hjärnfonden; doi: http://dx.doi.org/10.13039/501100003792Funder: Cancerfonden; doi: http://dx.doi.org/10.13039/501100002794Funder: Vetenskapsrådet; doi: http://dx.doi.org/10.13039/501100004359Funder: Alzheimerfonden; doi: http://dx.doi.org/10.13039/501100008599Funder: Konung Gustaf V:s och Drottning Victorias Frimurarestiftelse (SE)Funder: Science for Life Laboratory (SE)Funder: Fundacja na rzecz Nauki Polskiej (PL)Funder: Uppsala UniversityAbstract: Epidemiological investigations show that mosaic loss of chromosome Y (LOY) in leukocytes is associated with earlier mortality and morbidity from many diseases in men. LOY is the most common acquired mutation and is associated with aberrant clonal expansion of cells, yet it remains unclear whether this mosaicism exerts a direct physiological effect. We studied DNA and RNA from leukocytes in sorted- and single-cells in vivo and in vitro. DNA analyses of sorted cells showed that men diagnosed with Alzheimer’s disease was primarily affected with LOY in NK cells whereas prostate cancer patients more frequently displayed LOY in CD4 + T cells and granulocytes. Moreover, bulk and single-cell RNA sequencing in leukocytes allowed scoring of LOY from mRNA data and confirmed considerable variation in the rate of LOY across individuals and cell types. LOY-associated transcriptional effect (LATE) was observed in ~ 500 autosomal genes showing dysregulation in leukocytes with LOY. The fraction of LATE genes within specific cell types was substantially larger than the fraction of LATE genes shared between different subsets of leukocytes, suggesting that LOY might have pleiotropic effects. LATE genes are involved in immune functions but also encode proteins with roles in other diverse biological processes. Our findings highlight a surprisingly broad role for chromosome Y, challenging the view of it as a “genetic wasteland”, and support the hypothesis that altered immune function in leukocytes could be a mechanism linking LOY to increased risk for disease