New physics searches at kaon and hyperon factories

Rare meson decays are among the most sensitive probes of both heavy and light new physics. Among them, new physics searches using kaons benefit from their small total decay widths and the availability of very large datasets. On the other hand, useful complementary information is provided by hyperon decay measurements. We summarize the relevant phenomenological models and the status of the searches in a comprehensive list of kaon and hyperon decay channels. We identify new search strategies for under-explored signatures, and demonstrate that the improved sensitivities from current and next-generation experiments could lead to a qualitative leap in the exploration of light dark sectors.

Création d'un algorithme d'identification d'expériences vécues par des patients ou leurs proches à partir de messages issus des réseaux sociaux : un cas d'usage sur le COVID long

Introduction

La pandémie de COVID-19 a entrainé une masse d'informations sur les réseaux sociaux et forums provenant de multiples acteurs : gouvernements, journalistes ou encore citoyens. Parmi ces messages, de nombreux patients se sont saisis de ces outils pour partager leurs symptômes et se regrouper en communauté, comme c'est le cas des patients atteints de COVID long avec le hashtag #aprèsJ20. Un algorithme de traitement automatique du langage naturel capable d'identifier les messages constituant des expériences de santé vécues par des patients ou des proches permettrait d'exploiter ces données de vie réelle dans un objectif de santé publique.

Méthodes

A partir de différentes sources, 12 430 messages issus de forums et réseaux sociaux (Twitter, Facebook) ont été extraits sur différentes pathologies : cancer (sans précision d'une localisation), diabète, maladie de Fabry, COVID-19, sevrage tabagique. Ces messages ont été manuellement analysées et codifiées en trois catégories selon la nature de l'internaute : patient/aidant ou proche/répondant. Sur la base de ce « gold standard », un modèle de « machine learning » a été créé et entrainé, couplé avec des champs lexicaux marqueurs d'expériences vécues (par exemple, la présence d'un récit à la première personne ou du champ lexical de la famille). Deux modèles Xgboost ont été choisis permettant de déterminer en premier lieu si l'internaute est un proche de malade ou non, puis dans un second temps, si c'est un patient ou non. Pour être validé, ce modèle a été appliqué sur des messages spécifiques au COVID long. Une sélection aléatoire de ces messages couplée à une annotation par trois annotateurs a permis de mesurer les performances du modèle.

Résultats

Après application de l'algorithme d'identification d'expériences vécues par des patients ou des proches, 700 messages ont été revus et annotés sur le COVID long. Les catégories patients et aidants ont été regroupées en raison des nombreux cas de formes familiales de COVID long rapportés sur les réseaux sociaux. Les performances du modèle ont permis de mesurer une sensibilité de 96 %, une spécificité de 76 %, une « accuracy » à 87 % et une précision de 84 %.

Conclusion

Un algorithme identifiant les expériences vécues par des patients ou des proches au sein des messages issus des réseaux sociaux facilite leur utilisation comme données de vie réelle. Les bonnes performances de l'algorithme, notamment sur les formes longues de COVID-19, permettent un suivi prospectif de ces patients dans un objectif de santé publique. Une future version du modèle devra intégrer la possibilité d'identifier au sein d'un même message la présence d'expériences à la fois de patients et de proches, notamment en cas de formes familiales (”mon fils et moi avons un covid long ”).

Déclaration de liens d'intérêts

Les auteurs n'ont pas précisé leurs éventuels liens d'intérêts.

Consistent Treatment of Axions in the Weak Chiral Lagrangian

We present a consistent implementation of weak decays involving an axion or axionlike particle in the context of an effective chiral Lagrangian. We argue that previous treatments of such processes have used an incorrect representation of the flavor-changing quark currents in the chiral theory. As an application, we derive model-independent results for the decays K^{-}→π^{-}a and π^{-}→e^{-}ν[over ¯]_{e}a at leading order in the chiral expansion and for arbitrary axion couplings and mass. In particular, we find that the K^{-}→π^{-}a branching ratio is almost 40 times larger than previously estimated.

O-135 Long term secondary efficacy of linzagolix for heavy menstrual bleeding (HMB) due to uterine fibroids (UF): 52-week results from two placebo-controlled, randomized, phase 3 trials

Study question

Are symptomatic improvements in women with UF observed after 24 weeks of linzagolix treatment with or without add-back therapy (ABT) maintained over 52 weeks?

Summary answer

Improvements in anemia, pain and quality of life previously reported at 24 weeks were maintained at 52 weeks.

What is known already

We previously reported that partial or full suppression of estradiol (E2) with once daily doses of either 100 or 200 mg linzagolix for 24 weeks, with or without ABT, were effective in reducing heavy menstrual bleeding associated with uterine fibroids, improving other symptoms such as pain and anemia and improving quality of life. Here we report the maintenance of effect on secondary endpoints after 52 weeks of treatment.

Study design, size, duration

Linzagolix is an investigational, oral GnRH antagonist being developed to treat HMB due to UF. PRIMROSE 1 (P1, USA, NCT03070899) and PRIMROSE 2 (P2, Europe and USA, NCT03070951) are randomized, double-blind, placebo-controlled Phase 3 trials, with essentially identical design, investigating the efficacy and safety of linzagolix with and without hormonal add-back therapy (ABT: 1 mg estradiol/0.5 mg norethindrone acetate) once daily for 52 weeks.

Participants/materials, setting, methods

Participants had HMB due to UF (>80mL menstrual blood loss (MBL)/cycle) and were equally randomized to: placebo, linzagolix 100mg, linzagolix 100mg+ABT, linzagolix 200mg, or linzagolix 200mg+ABT. After 24 weeks, subjects originally randomized to placebo or linzagolix 200mg were switched to linzagolix 200mg+ABT except in P1 where 50% placebo subjects continued placebo until 52 weeks. Secondary efficacy assessments included hemoglobin, pain (0–10 numeric rating scale) and health related quality of life (HRQL) on the UF-QoL questionnaire.

Main results and the role of chance

P1 trial subjects (n = 526) had a mean age of 42 years, pain score of 6.6 and HRQL total score (0–100) of 36.4 and 63% were Black. P2 trial subjects (n = 511) had a mean age of 43 years, pain score 4.8 and HRQL total score of 46.1 and 5% were Black. Mean baseline MBL was about 200 mL per cycle in both studies. In both trials, significant improvements compared to placebo observed at week 24 for secondary endpoints, including pain, anemia and QoL in all linzagolix treatment groups were maintained at 52 weeks.

Mean±SD hemoglobin levels in anemic patients (<12 g/dL) increased from baseline by 1.7±1.9, 1.9±1.7, 2.2±2.4, 2.7±1.9 in P1 and 1.2±1.9, 2.9±1.8, 2.4±2.1, 3.0±1.4 in P2 in the 100mg, 100mg+ABT, 200mg/200mg+ABT, 200mg+ABT groups, respectively, compared to 0.6±1.8 with placebo (P1).

Mean±SD change from baseline in pain scores were -3.3±3.1, -2.7±3.2, -2.6±3.0, -3.9±3.2 in P1 and -2.6±3.1, -2.6±2.8, -3.0±2.6, -2.8±3.0 in P2 in the 100mg, 100mg+ABT, 200mg/200mg+ABT, 200mg+ABT groups, respectively, compared to -0.4±2.5 with placebo (P1).

Mean±SD change in HRQL total scores were 25.0±26.2, 34.2±30.1, 29.7±29.2, 38.3±29.2 in P1 and 16.8±24.0, 29.6±23.2, 31.9±26.8, 30.7±26.0 in P2 in the 100mg, 100mg+ABT, 200mg/200mg+ABT, 200mg+ABT groups, respectively, compared to 14.6±23.9 with placebo (P1).

Limitations, reasons for caution

Here we report data in both trials up to 52 weeks of treatment. No statistical comparisons were done at 52 weeks (the primary analysis was done after 24 weeks treatment). Post-treatment follow-up will provide more information in symptom recurrence after stopping treatment.

Wider implications of the findings

All linzagolix treatments provided sustained benefit. Two regimens previously identified for potential long-term treatment, 200mg with ABT and 100mg without ABT, provided sustained improvements of anemia, pain and associated quality of life. These different treatment regimens could be important to address the diverse needs of women suffering from uterine fibroids.

Trial registration number

ClinicalTrials.gov: NCT03070899, NCT03070951

Axionlike Particles, Lepton-Flavor Violation, and a New Explanation of a_{μ} and a_{e}

Axionlike particles (ALPs) with lepton-flavor-violating couplings can be probed in exotic muon and tau decays. The sensitivity of different experiments depends strongly on the ALP mass and its couplings to leptons and photons. For ALPs that can be resonantly produced, the sensitivity of three-body decays such as μ→3e and τ→3μ exceeds by many orders of magnitude that of radiative decays like μ→eγ and τ→μγ. Searches for these two types of processes are therefore highly complementary. We discuss experimental constraints on ALPs with a single dominant lepton-flavor-violating coupling. Allowing for one or more such couplings offers qualitatively new ways to explain the anomalies related to the magnetic moments of the muon or the electron. The explanation of both anomalies requires lepton-flavor-nonuniversal or lepton-flavor-violating ALP couplings.

[CF Lung Disease - a German S3 Guideline: Module 2: Diagnostics and Treatment in Chronic Infection with Pseudomonas aeruginosa]

Cystic Fibrosis (CF) is the most common autosomal-recessive genetic disease affecting approximately 8000 people in Germany. The disease is caused by mutations in the Cystic Fibrosis Transmembrane Conductance Regulator (CFTR) gene leading to dysfunction of CFTR, a transmembrane chloride channel. This defect causes insufficient hydration of the epithelial lining fluid which leads to chronic inflammation of the airways. Recurrent infections of the airways as well as pulmonary exacerbations aggravate chronic inflammation, lead to pulmonary fibrosis and tissue destruction up to global respiratory insufficiency, which is responsible for the mortality in over 90 % of patients. The main aim of pulmonary treatment in CF is to reduce pulmonary inflammation and chronic infection. Pseudomonas aeruginosa (Pa) is the most relevant pathogen in the course of CF lung disease. Colonization and chronic infection are leading to additional loss of pulmonary function. There are many possibilities to treat Pa-infection. This is a S3-clinical guideline which implements a definition for chronic Pa-infection and demonstrates evidence-based diagnostic methods and medical treatment for Pa-infection in order to give guidance for individual treatment options.

Testing Dragonflies as Species Richness Indicators in a Fragmented Subtropical Atlantic Forest Environment

We surveyed 15 bodies of water among remnants of the Atlantic Forest biome in southern Brazil for adult dragonflies and damselflies to test whether an empirical selection method for diversity indicators could be applied in a subtropical ecosystem, where limited ecological knowledge on species level is available. We found a regional species pool of 34 species distributed in a nested subset pattern with a mean of 11.2 species per locality. There was a pronounced difference in species composition between spring, summer, and autumn, but no differences in species numbers between seasons. Two species, Homeoura chelifera (Selys) and Ischnura capreolus (Hagen), were the strongest candidates for regional diversity indicators, being found only at species-rich localities in our surveyed area and likewise in an undisturbed national forest reserve, serving as a reference site for the Atlantic Forest. Using our selection method, we found it possible to obtain a tentative list of diversity indicators without having detailed ecological information of each species, providing a reference site is available for comparison. The method thus allows for indicator species to be selected in blanco from taxonomic groups that are little known. We hence argue that Odonata can already be incorporated in ongoing assessment programs in the Neotropics, which would also increase the ecological knowledge of the group and allow extrapolation to other taxa.

Automatic texture-based analysis in ultrasound imaging of ovarian masses

PURPOSE

To assess the diagnostic accuracy of a new automatic texture-based algorithm (ATBA) in ultrasound imaging of ovarian masses and to compare its performance to subjective assessment by examiners with different levels of ultrasound experience.

MATERIALS AND METHODS

A total of 105 ultrasound images from three different groups of ovarian lesions (malignancies, functional cysts, and dermoid cysts) were evaluated using ATBA and by a total of 36 examiners with four different levels of experience (9 junior trainees, 8 senior trainees, 11 senior gynecologists, and 8 experts). Cohen's κ, Youden's indices, and the sensitivity and specificity of ATBA and of each observer were calculated for every subgroup of ovarian lesions.

RESULTS

ATBA classified 78 of the 105 masses correctly (κ = 0.62) - results that were significantly better than those of the junior and senior trainees (p = 0.02 and p < 0.01), while differences from the group of level II examiners did not reach statistical significance (p = 0.27). The best diagnostic performance (κ = 0.70) was obtained by the group of expert level III ultrasonographers. The best classification rates overall, including both ATBA and subjective assessments, were achieved in the detection of functional cysts (Youden's indices from 0.73 to 0.85), while the poorest diagnostic performance was obtained for the classification of dermoid cysts (Youden's indices from 0.28 to 0.55).

CONCLUSION

ATBA showed a significantly better diagnostic performance than observers with low or medium levels of experience, emphasizing its potential value for training purposes and in providing additional diagnostic assistance for inexperienced observers.

424 DOMINANT-NEGATIVE GLUCOSE-DEPENDENT INSULINOTROPIC POLYPEPTIDE (GIP) RECEPTOR (GIPRdn)TRANSGENIC PIGS — A LARGE ANIMAL MODEL FOR TYPE 2 DIABETES MELLITUS

The incretin hormones glucose-dependent insulinotropic polypeptide (GIP) and glucagon-like peptide-1 (GLP-1) are secreted in response to nutrients and enhance glucose-induced insulin secretion. The insulinotropic action of GIP is impaired in type 2 diabetes (T2D) whereas that of GLP-1 is preserved. To evaluate the role of an impaired GIP function in the pathogenesis of T2D in a large animal model, we generated transgenic pigs expressing a dominant-negative GIP receptor (GIPRdn) in the pancreatic islets. GIPRdn transgenic pigs were generated using lentiviral transgenesis. Metabolic tests and quantitative stereological analyses of the pancreas were performed in 3 different age groups to investigate the effects of an impaired insulinotropic action of GIP on glucose metabolism and pancreas morphology. The insulinotropic action of GIP was significantly reduced, whereas insulin secretion in response to the GLP-1 receptor agonist exendin-4 was enhanced in 11-week-old GIPRdn transgenic pigs compared with control pigs. Eleven-week-old GIPRdn transgenic pigs (n = 5) exhibited significantly reduced oral glucose tolerance (P < 0.05) with a delay in insulin secretion compared with controls (n = 5). The area under the insulin curve (AUC) during the first 45 min following glucose load was 31% smaller (P < 0.05) in transgenic pigs compared with controls. The total insulin secretion capacity was not different between the 2 groups indicating that GIPRdn expression initially only interferes with the incretin effect. This was supported by the fact that intravenous glucose tolerance and insulin secretion in transgenic pigs were not different from controls. Five-month-old GIPRdn transgenic pigs revealed markedly reduced insulin secretion in response to oral glucose challenge (P < 0.01), resulting in significantly elevated glucose levels (P < 0.05). Also, intravenous glucose tolerance and insulin secretion were diminished in 11-month-old transgenic pigs. To determine the reason for the alterations in glucose metabolism, quantitative-stereological analyses of the pancreas were performed. In 11-week-old pigs, transgenic and control groups showed similar β-cell mass (n = 5 in each group). However, pancreatic β-cell mass was reduced by almost 40% (P < 0.05) in 5-month-old pigs and by 60% (P < 0.01) in adult (1 to 1.4 years) GIPRdn transgenic pigs compared with controls. To investigate the reason for the progressive reduction of pancreatic β-cell mass in GIPRdn transgenic pigs, β-cell proliferation rate was determined performing a double-immunohistochemistry for insulin and the proliferation marker Ki67. Eleven-week-old GIPRdn transgenic pigs showed significantly fewer Ki67-positive cell nuclei compared with controls (P < 0.05). In conclusion, GIPRdn transgenic pigs exhibit a comparable situation to T2D, such as impaired insulinotropic action of GIP, disturbed oral and intravenous glucose tolerance, and progressive reduction of β-cell mass. These alterations are at least partly attributable to diminished proliferation of β-cells. Grant support: Deutsche Forschungsgemeinschaft (GRK 1029), Bayerische Forschungsstiftung (492/02).

433 NEW TRANSGENIC PIG DIABETES MODEL EXPRESSING THE MUTANT Insulinc93S FOR THE STUDY OF THE PANCREATIC BETA CELL DYSFUNCTION

We previously established a mutant mouse line showing diabetes which was caused by a point mutation in the Insulin 2 (Ins2) gene. The point mutation leads to the amino acid exchange C95S and the loss of the A6-A11 intrachain disulfide bond of insulin. Male heterozygous Ins2C95S mutant mice develop progressive diabetes mellitus with strong reduction of the total pancreatic islet volume and the total beta cell volume together with severe alterations of the beta cell structure. As pigs share many anatomical and physiological characteristics with humans, we aimed to establish a transgenic pig model expressing the mutant insulin by additive gene transfer for the subsequent study of beta cell dysfunction in diabetes mellitus. The transgene consisted of German Landrace insulin sequences including 1.3 kb of the insulin promoter and 1 kb insulin gene sequences with the 3 exons and the T to A (C93S) point mutation in exon 3 analogous to the mutant mouse insulin. A floxed neomycin resistance gene at the 3′ end of the transgene was used as a selection marker. After successful transfection of male fetal fibroblasts of both the German Landrace and the Schwaebisch- Haellisch pig breeds, pooled transgenic fibroblasts were used for somatic cell nuclear transfer (SCNT). Five hundred three reconstructed pig embryos were generated and endoscopically transferred to 5 synchronized recipients. One pregnancy with German Landrace genetic background and one pregnancy with Schwaebisch-Haellisch genetic background of the cloned embryos developed to term, which gave rise to 3 living offspring from each of the 2 pregnancies; 5 of the 6 piglets were transgenic. Southern blot analysis showed different transgene signal patterns in all animals examined. Transgenic pigs of both litters revealed unaltered fasting blood glucose levels up to an age of 8 months. However, disturbed intravenous glucose tolerance and reduced insulin secretion were detected in 1 transgenic pig of the first litter at 8 months of age. The area under the glucose curve of this transgenic pig was 75% larger (22 136 v. 12617) and the area under the insulin curve 53% smaller (1250 v. 2670) compared with the control. Ongoing analyses comprise glucose tolerance tests in the second litter as well as pathohistologic analysis of the pancreata of both litters. Cells from suitable transgenic founders will be used for recloning to establish a new transgenic pig model expressing the mutant InsulinC93S for an in-depth study of pancreatic beta cell dysfunction in diabetes mellitus. Supported by the Deutsche Forschungsgemeinschaft (GRK1029).

Assembly and melting of DNA nanotubes from single-sequence tiles

DNA melting and renaturation studies are an extremely valuable tool to study the kinetics and thermodynamics of duplex dissociation and reassociation reactions. These are important not only in a biological or biotechnological context, but also for DNA nanotechnology which aims at the construction of molecular materials by DNA self-assembly. We here study experimentally the formation and melting of a DNA nanotube structure, which is composed of many copies of an oligonucleotide containing several palindromic sequences. This is done using temperature-controlled UV absorption measurements correlated with atomic force microscopy, fluorescence microscopy and transmission electron microscopy techniques. In the melting studies, important factors such as DNA strand concentration, hierarchy of assembly and annealing protocol are investigated. Assembly and melting of the nanotubes are shown to proceed via different pathways. Whereas assembly occurs in several hierarchical steps related to the formation of tiles, lattices and tubes, melting of DNA nanotubes appears to occur in a single step. This is proposed to relate to fundamental differences between closed, three-dimensional tube-like structures and open, two-dimensional lattices. DNA melting studies can lead to a better understanding of the many factors that affect the assembly process which will be essential for the assembly of increasingly complex DNA nanostructures.

4 IMPAIRED INCRETIN EFFECT IN TRANSGENIC PIGS EXPRESSING A DOMINANT NEGATIVE RECEPTOR FOR GLUCOSE-DEPENDENT INSULINOTROPIC POLYPEPTIDE IN THE PANCREATIC ISLETS

Glucose-dependent insulinotropic polypeptide (GIP) and glucagon-like peptide-1 (GLP-1) are secreted by specific cell types in the intestine and are responsible for the so-called incretin effect, the phenomenon that an oral glucose load elicits a higher insulin response than does an intravenous glucose load. In patients with type 2 diabetes mellitus the overall incretin effect is reduced. This fact is mostly attributed to a lowered insulinotropic effect of GIP, while the effect of GLP-1 is preserved. In order to better understand the consequences of impaired function of GIP, knockout mice lacking a functional GIP receptor (GIPR–/–) as well as transgenic mice expressing a dominant negative GIPR (GIPRdn) were established. While GIPR–/– mice show only relatively mild changes in glucose homeostasis, GIPRdn mice display a distinct diabetic phenotype due to disturbed development of the endocrine pancreas (Herbach et al. 2005 Regul. Pept. 125, 103–117). To further clarify the underlying mechanisms, we used a novel, highly efficient gene transfer technology based on lentiviral vectors (Hofmann et al. 2003 EMBO Rep. 4, 1054–1060; Hofmann et al. 2006 Mol. Ther. 13, 59–66) to generate transgenic pigs expressing a GIPRdn under the control of the rat Ins2 promoter (RIP). RIP-GIPRdn transgenic pigs develop normally and do not display diabetes mellitus up to at least one year of age. Weekly measured fasting blood glucose levels in transgenic animals did not show a significant difference compared to control pigs. The same was true for monthly determined fructosamine levels. However, RIP-GIPRdn transgenic pigs exhibited reduced insulin release and higher glucose levels than non-transgenic littermate controls in an oral glucose tolerance test. The area under the curve (AUC) for insulin was 49% smaller (P < 0.01) and the AUC for glucose 26% larger (P < 0.05) in RIP-GIPRdn transgenic pigs (n = 5) than in their non-transgenic littermate controls (n = 5). These findings demonstrate that expression of a GIPRdn, which was shown by RT-PCR in isolated pancreatic islets, disturbs the function of GIP in transgenic pigs. Thus we have created a novel, clinically relevant animal model for studying the roles of the GIP/GIPR system. Quantitative morphological studies of the pancreas are being performed to clarify whether GIPR function is essential for pancreatic islet development and maintenance.