State changes of the HORMA protein ASY1 are mediated by an interplay between its closure motif and PCH2.

HORMA domain-containing proteins (HORMADs) play an essential role in meiosis in many organisms. The meiotic HORMADs, including yeast Hop1, mouse HORMAD1 and HORMAD2, and Arabidopsis ASY1, assemble along chromosomes at early prophase and the closure motif at their C-termini has been hypothesized to be instrumental for this step by promoting HORMAD oligomerization. In late prophase, ASY1 and its homologs are progressively removed from synapsed chromosomes promoting chromosome synapsis and recombination. The conserved AAA+ ATPase PCH2/TRIP13 has been intensively studied for its role in removing HORMADs from synapsed chromosomes. In contrast, not much is known about how HORMADs are loaded onto chromosomes. Here, we reveal that the PCH2-mediated dissociation of the HORMA domain of ASY1 from its closure motif is important for the nuclear targeting and subsequent chromosomal loading of ASY1. This indicates that the promotion of ASY1 to an 'unlocked' state is a prerequisite for its nuclear localization and chromosomal assembly. Likewise, we find that the closure motif is also necessary for the removal of ASY1 by PCH2 later in prophase. Our work results in a unified new model for PCH2 and HORMADs function in meiosis and suggests a mechanism to contribute to unidirectionality in meiosis.

Perceptions and attitudes towards climate change in fishing communities of the Sudd Wetlands, South Sudan.

The Sudd in South Sudan, formed by the White Nile's Bahr al-Jabal section, is one of the largest and most important wetlands in the world. Communities in the region almost exclusively depend on fisheries for food and livelihoods. Although threatened by over-exploitation and habitat changes, fish populations are also affected by climate change. Using semi-structured questionnaires, we assessed fisherfolk's opinions of how recent variation in climate affected their livelihoods and the environment. Fisherfolk perceived that climate had changed in the past decade and were negatively impacted by this. Interviewees reported average higher temperatures, a greater frequency of floods and droughts, unpredictable timing of seasons, and erratic rainfall. Destruction of fishing villages/camps, loss and damage of fishing equipment, shifts in the fishing calendar, reduction of fish trade, and fish catch declines as well as psycho-social problems were given as the major consequences of climate change. Causes of climate change and variability were perceived to be linked to uncontrolled harvest of forest resources, anger of God and ancestors, and natural variability in climate. Most respondents expressed a desire to adopt more responsible behavior such as planting trees and establishing community nurseries, being educated on climate change risks, and sustainable fisheries management. Our results show that fisherfolk in the Sudd are troubled by climate change impacts on their livelihoods and on fish populations. In South Sudan, climate change has been reported from hydroclimatological data but concrete impacts on people remain largely unknown and of little concern because of recent wars and the poor economy. Our study provides an example of how fisherfolks' local ecological knowledge (LEK) can be used as an early warning system of the negative impacts on livelihoods and fish populations and support adaptation to the changing climate. Supplementary Information: The online version contains supplementary material available at 10.1007/s10113-022-01928-w.

Lung development and immune status under chronic LPS exposure in rat pups with and without CD26/DPP4 deficiency.

Dipeptidyl-peptidase IV (CD26), a multifactorial integral type II protein, is expressed in the lungs during development and is involved in inflammation processes. We tested whether daily LPS administration influences the CD26-dependent retardation in morphological lung development and induces alterations in the immune status. Newborn Fischer rats with and without CD26 deficiency were nebulized with 1 µg LPS/2 ml NaCl for 10 min from days postpartum (dpp) 3 to 9. We used stereological methods and fluorescence activated cell sorting (FACS) to determine morphological lung maturation and alterations in the pulmonary leukocyte content on dpp 7, 10, and 14. Daily LPS application did not change the lung volume but resulted in a significant retardation of alveolarization in both substrains proved by significantly lower values of septal surface and volume as well as higher mean free distances in airspaces. Looking at the immune status after LPS exposure compared to controls, a significantly higher percentage of B lymphocytes and decrease of CD4+CD25+ T cells were found in both subtypes, on dpp7 a significantly higher percentage of CD4 T+ cells in CD26+ pups, and a significantly higher percentage of monocytes in CD26- pups. The percentage of T cells was significantly higher in the CD26-deficient group on each dpp. Thus, daily postnatal exposition to low doses of LPS for 1 week resulted in a delay in formation of secondary septa, which remained up to dpp 14 in CD26- pups. The retardation was accompanied by moderate parenchymal inflammation and CD26-dependent changes in the pulmonary immune cell composition.

PMR4-dependent cell wall depositions are a consequence but not the cause of temperature-induced autoimmunity.

Plants possess a well-balanced immune system that is required for defense against pathogen infections. In autoimmune mutants or necrotic crosses, an intrinsic temperature-dependent imbalance leads to constitutive immune activation, resulting in severe damage or even death of plants. Recently, cell wall depositions were described as one of the symptoms following induction of the autoimmune phenotype in Arabidopsis saul1-1 mutants. However, the regulation and function of these depositions remained unclear. Here, we show that cell wall depositions, containing lignin and callose, were a common autoimmune feature and were deposited in proportion to the severity of the autoimmune phenotype at reduced ambient temperatures. When plants were exposed to reduced temperature for periods insufficient to induce an autoimmune phenotype, the cell wall depositions were not present. After low temperature intervals, sufficient to induce autoimmune responses, cell wall depositions correlated with a point of no return in saul1-1 autoimmunity. Although cell wall depositions were largely abolished in saul1-1 pmr4-1 double mutants lacking SAUL1 and the callose synthase gene GSL5/PMR4, their phenotype remained unchanged compared to that of the saul1-1 single mutant. Our data showed that cell wall depositions generally occur in autoimmunity, but appear not to be the cause of autoimmune phenotypes.

Implications of early respiratory support strategies on disease progression in critical COVID-19: a matched subanalysis of the prospective RISC-19-ICU cohort.

BACKGROUND: Uncertainty about the optimal respiratory support strategies in critically ill COVID-19 patients is widespread. While the risks and benefits of noninvasive techniques versus early invasive mechanical ventilation (IMV) are intensely debated, actual evidence is lacking. We sought to assess the risks and benefits of different respiratory support strategies, employed in intensive care units during the first months of the COVID-19 pandemic on intubation and intensive care unit (ICU) mortality rates. METHODS: Subanalysis of a prospective, multinational registry of critically ill COVID-19 patients. Patients were subclassified into standard oxygen therapy ≥10 L/min (SOT), high-flow oxygen therapy (HFNC), noninvasive positive-pressure ventilation (NIV), and early IMV, according to the respiratory support strategy employed at the day of admission to ICU. Propensity score matching was performed to ensure comparability between groups. RESULTS: Initially, 1421 patients were assessed for possible study inclusion. Of these, 351 patients (85 SOT, 87 HFNC, 87 NIV, and 92 IMV) remained eligible for full analysis after propensity score matching. 55% of patients initially receiving noninvasive respiratory support required IMV. The intubation rate was lower in patients initially ventilated with HFNC and NIV compared to those who received SOT (SOT: 64%, HFNC: 52%, NIV: 49%, p = 0.025). Compared to the other respiratory support strategies, NIV was associated with a higher overall ICU mortality (SOT: 18%, HFNC: 20%, NIV: 37%, IMV: 25%, p = 0.016). CONCLUSION: In this cohort of critically ill patients with COVID-19, a trial of HFNC appeared to be the most balanced initial respiratory support strategy, given the reduced intubation rate and comparable ICU mortality rate. Nonetheless, considering the uncertainty and stress associated with the COVID-19 pandemic, SOT and early IMV represented safe initial respiratory support strategies. The presented findings, in agreement with classic ARDS literature, suggest that NIV should be avoided whenever possible due to the elevated ICU mortality risk.

Early postnatal behavioral, cellular, and molecular changes in models of Huntington disease are reversible by HDAC inhibition.

Huntington disease (HD) is an autosomal dominant neurodegenerative disorder caused by expanded CAG repeats in the huntingtin gene (HTT). Although mutant HTT is expressed during embryonic development and throughout life, clinical HD usually manifests later in adulthood. A number of studies document neurodevelopmental changes associated with mutant HTT, but whether these are reversible under therapy remains unclear. Here, we identify very early behavioral, molecular, and cellular changes in preweaning transgenic HD rats and mice. Reduced ultrasonic vocalization, loss of prepulse inhibition, and increased risk taking are accompanied by disturbances of dopaminergic regulation in vivo, reduced neuronal differentiation capacity in subventricular zone stem/progenitor cells, and impaired neuronal and oligodendrocyte differentiation of mouse embryo-derived neural stem cells in vitro. Interventional treatment of this early phenotype with the histone deacetylase inhibitor (HDACi) LBH589 led to significant improvement in behavioral changes and markers of dopaminergic neurotransmission and complete reversal of aberrant neuronal differentiation in vitro and in vivo. Our data support the notion that neurodevelopmental changes contribute to the prodromal phase of HD and that early, presymptomatic intervention using HDACi may represent a promising novel treatment approach for HD.

Can commercially available wearable EEG devices be used for diagnostic purposes? An explorative pilot study.

Electroencephalography (EEG) is a core element in the diagnosis of epilepsy syndromes and can help to monitor antiseizure treatment. Mobile EEG (mEEG) devices are increasingly available on the consumer market and may offer easier access to EEG recordings especially in rural or resource-poor areas. The usefulness of consumer-grade devices for clinical purposes is still underinvestigated. Here, we compared EEG traces of a commercially available mEEG device (Emotiv EPOC) to a simultaneously recorded clinical video EEG (vEEG). Twenty-two adult patients (11 female, mean age 40.2 years) undergoing noninvasive vEEG monitoring for clinical purposes were prospectively enrolled. The EEG recordings were evaluated by 10 independent raters with unmodifiable view settings. The individual evaluations were compared with respect to the presence of abnormal EEG findings (regional slowing, epileptiform potentials, seizure pattern). Video EEG yielded a sensitivity of 56% and specificity of 88% for abnormal EEG findings, whereas mEEG reached 39% and 85%, respectively. Interrater reliability coefficients were better in vEEG as compared to mEEG (ϰ = 0.50 vs. 0.30), corresponding to a moderate and fair agreement. Intrarater reliability between mEEG and vEEG evaluations of simultaneous recordings of a given participant was moderate (ϰ = 0.48). Given the limitations of our exploratory pilot study, our results suggest that vEEG is superior to mEEG, but that mEEG can be helpful for diagnostic purposes. We present the first quantitative comparison of simultaneously acquired clinical and mobile consumer-grade EEG for a clinical use-case.

360-degree Delphi: addressing sociotechnical challenges of healthcare IT.

BACKGROUND: IT systems in the healthcare field can have a marked sociotechnical impact: they modify communication habits, alter clinical processes and may have serious ethical implications. The introduction of such systems involves very different groups of stakeholders because of the inherent multi-professionalism in medicine and the role of patients and their relatives that are often underrepresented. Each group contributes distinct perspectives and particular needs, which create specific requirements for IT systems and may strongly influence their acceptance and success. In the past, needs analysis, challenges and requirements for medical IT systems have often been addressed using consensus techniques such as the Delphi technique. Facing the heterogeneous spectrum of stakeholders there is a need to develop these techniques further to control the (strong) influence of the composition of the expert panel on the outcome and to deal systematically with potentially incompatible needs of stakeholder groups. This approach uses the strong advantages a Delphi study has, identifies the disadvantages of traditional Delphi techniques and aims to introduce and evaluate a modified approach called 360-Degree Delphi. Key aspects of 360-Degree Delphi are tested by applying the approach to the needs and requirements analysis of a system for managing patients' advance directives and living wills. METHODS: 360-Degree Delphi (short 360°D), as a modified Delphi process, is specified as a structured workflow with the optional use of stakeholder groups. The approach redefines the composition of the expert panel by setting up groups of different stakeholders. Consensus is created within individual stakeholder groups, but is also communicated between groups, while the iterative structure of the Delphi process remains unchanged. We hypothesize that (1) 360-Degree Delphi yields complementary statements from different stakeholders, which would be lost in classical Delphi; while (2) the variation of statements within individual stakeholder groups is lower than within the total collective. A user study is performed that addresses five stakeholder groups (patients, relatives, medical doctors, nurses and software developers) on the topic of living will communication in an emergency context. Qualitative open questions are used in a Delphi round 0. Answer texts are coded by independent raters who carry out systematic bottom-up qualitative text analysis. Inter-rater reliability is calculated and the resulting codes are used to test the hypotheses. Qualitative results are transferred into quantitative questions and then surveyed in round 1. The study took place in Germany. RESULTS: About 25% of the invited experts (stakeholders) agreed to take part in the Delphi round 0 (three patients, two relatives, three medical doctors, two qualified nurses and three developers), forming a structured panel of the five stakeholder groups. Two raters created a bottom-up coding, and 238 thematic codes were identified by the qualitative text analysis. The inter-rater reliability showed that 44.95% of the codes were semantically similar and coded for the same parts of the raw textual replies. Based on a consented coding list, a quantitative online-questionnaire was developed and send to different stakeholder groups. With respect to the hypotheses, Delphi round 0 had the following results: (1) doctors had a completely different focus from all the other stakeholder groups on possible channels of communications with the patient; (2) the dispersion of codes within individual stakeholder groups and within the total collective - visualized by box plots - was approximately 28% higher in the total collective than in the sub-collectives, but without a marked effect size. With respect to the hypotheses, Delphi round 1 had the following results: different stakeholder groups had highly diverging opinions with respect to central questions on IT-development. For example, when asked to rate the importance of access control against high availability of data (likert scale, 1 meaning restrictive data access, 6 easy access to all data), patients (mean 4.862, Stdev +/- 1.866) and caregivers (mean 5.667, Stdev: +/- 0.816) highly favored data availability, while relatives would restrict data access (mean 2.778, stdev +/- 1.093). In comparison, the total group would not be representative of either of these individual stakeholder needs (mean 4.344, stdev +/- 1.870). CONCLUSION: 360-Degree Delphi is feasible and allows different stakeholder groups within an expert panel to reach agreement individually. Thus, it generates a more detailed consensus which pays more tribute to individual stakeholders needs. This has the potential to improve the time to consensus as well as to produce a more representative and precise needs and requirements analysis. However, the method may create new challenges for the IT development process, which will have to deal with complementary or even contradictory statements from different stakeholder groups.

[Negative Effects of Psychotherapy: Prevalence and Correlates in a Clinical Sample]. / Negative Effekte von Psychotherapie: Häufigkeit und Korrelate in einer klinischen Stichprobe.

INTRODUCTION: So far, the prevalence of negative effects of psychotherapy and their correlates have rarely been investigated in a systematic manner. The prevalence of negative effects varied between 3 studies with the Inventory for Assessing Negative Effects of Psychotherapy (INEP) with 20, 84, and 93.8% substantially. Thereby, the impact of bias effects remains unclear. In addition, reported correlates of the number of negative effects were examined and augmented with further correlates. MATERIAL AND METHODS: For the study, a clinical sample of inpatients and day-patients (N=200) evaluated their previous psychotherapy retrospectively before their current admission with the Inventory for Assessing Negative Effects of Psychotherapy (INEP). Sociodemographic and clinical data of both patients and therapists as well as time-related and methodical aspects of the evaluated psychotherapy were examined as possible correlates. RESULTS: 70.5% (n=141) of the patients reported at least one negative effect (M=2.11, SD=2.23). The most common negative effects were "longer periods of negative mood" (39.9%) and "being offended by statements of the therapist" (28%). Higher symptom severity, lower subjective success of the evaluated therapy, as well as unfulfilled expectations regarding therapy outcome but not the quality of the therapeutic relationship were associated with a higher number of negative effects. Also female gender of patient and therapist and a younger age of the therapist were significantly associated with more negative therapy effects. CONCLUSION: The prevalence of negative effects was not negligible. In line with previous studies, the highest rates of negative effects were reported for "symptoms" and aspects of the "therapeutic relationship". The study confirms several correlates for the number of retrospectively assessed negative effects. Patients need to be informed about negative effects prior to psychotherapeutic treatment.

Functions of the temporomandibular system in extracranial chronic pain conditions: modulatory effects on nocifensive behavior in an animal model.

OBJECTIVE: Mastication may be able to activate endogenous pain inhibitory mechanisms and therefore lead to modulation of nociceptive processing. The purpose of this study was to examine the possible effect of food consistency on noxious input from the spinal system. METHODS: Three groups of adult male Sprague-Dawley rats were given an injection of complete Freund adjuvant in a hind paw 10 days after eating soft or hard food (one group received a saline injection-the control group [C]; the other group (D) received no injection). Nocifensive behavior was assessed with the use of the hot plate and tail flick assays at 1, 3, 6, and 12 hours and at 6.5 days after injection for groups A/B, and c-Fos activity was assessed in the brain after testing. Groups C/D had hot plate testing at 1 hour and 6.5 days. The data were analyzed by general linear modeling and 1-way analysis of variance. RESULTS: There was a small increase in the hot plate percent maximum possible effect (MPE) from -45.7 to -61.1 in group A over the length of the experiment, but a very small decrease for group B over the same period (-33.5 to -28.8). For the saline control group, there was a small increase toward 0 %MPE over the same time frame (-15.0 to 1.7). The %MPE differences were significant between groups A and C (P < .0005), but not significant between the other groups (F = 13.34, df = 2, P = .001, observed power = 99%). Using the pooled results (all time points), the differences between all groups were significant (P < .0005). There were no significant differences in the tail flick test. c-Fos was mainly observed in the raphe pallidus area with significant differences between groups A and B at 3 and 6 hours after injection of CFA (P = .027 and .022, respectively). CONCLUSIONS: The results of this study indicate that food consistency (hardness) influences nocifensive behavior in this animal model via a descending pathway operating at the supraspinal level.

Development and testing of a questionnaire on the expectations and experiences with wearing face masks in inpatient and day hospitals.

BACKGROUND: The Covid-19 pandemic made wearing of face masks mandatory in the psychotherapeutic context. Against this background, the present study aimed to compare the expectations of patients undergoing day-hospital or inpatient treatment regarding wearing a mask in psychotherapy before the start of therapy with the final experience after the end of therapy. The study also investigated the extent to which expectations and experiences were influenced by other factors such as socio-demographic characteristics, patients' general attitudes towards wearing a mask, duration of treatment, or mental health diagnoses. METHODS: Patients' expectations and experiences were recorded using two versions of a self-developed questionnaire: the pre-version, which was administered before the start of therapy and recorded expectations, and the post-version, which was administered after the end of therapy and recorded the final experiences. An exploratory factor analysis was conducted for the questionnaire's pre- and post-version. T-tests for paired samples were calculated to compare the patients' expectations regarding the extracted factors with the final experiences. Bivariate correlations were calculated to explore the association of other potential factors with expectations and experiences. RESULTS: The exploratory factor analysis revealed a three-factor structure: communication barriers, self-confidence, and infection protection. The communication barriers expected by the patients before the start of the therapy turned out to be significantly higher than ultimately experienced after the therapy. Higher age correlated significantly negatively with expectations and experiences, with less self-confidence expected and experienced in therapy with a mask by older patients. There was a significant positive correlation between the expectations and the duration of treatment. Patients' general attitudes correlated significantly with their expectations and experiences. CONCLUSION: Based on the results, wearing a mask does not appear to negatively impact the success of psychotherapy from the patient's perspective. However, patient-specific characteristics also appear to play a role in this context.

Too little appreciation for great expenditure? Workload and resources in ICUs.

PURPOSE: The aim of this study was providing descriptive information and the comparative examination of job strain and mental health of nurses and physicians in different intensive care units (ICU). METHODS: The Effort-Reward Imbalance Questionnaire by Siegrist and standardized psychometric questionnaires, like Hospital Anxiety and Depression Scale, Impact of Event Scale, Brief Symptom Inventory, Social Support Questionnaire, and Life Satisfaction Questionnaire were used. Five ICUs of the same German medical school were included (N = 142). RESULTS: For all ICUs investigated, a significantly lower mental health and a high effort-reward imbalance were found when compared with other samples. Only a few differences between the wards or both professional groups (nurses vs. physicians) were noted. The values for social support were comparable with those of healthy controls but differed between the wards. The life satisfaction in our cohort was lower compared to a population-based sample but was significant different between the wards. CONCLUSIONS: Our study demonstrates the high job strain in an ICU, largely independent of the professional group. Noteworthy, a high effort-reward imbalance was found that stands in positive relation to adverse health effects (anxiety, depression, and general mental health). As a consequence, necessary interventions like stress management, supervision, and communication trainings should consider ward-specific conditions of employment rather than professional affiliation. After these interventions, a follow-up study will be performed to examine beneficial effects on job strain and health.

Enhanced attentional processing during speech perception in adult high-functioning autism spectrum disorder: An ERP-study.

Deficits in audiovisual speech perception have consistently been detected in patients with Autism Spectrum Disorder (ASD). Especially for patients with a highly functional subtype of ASD, it remains uncertain whether these deficits and underlying neural mechanisms persist into adulthood. Research indicates differences in audiovisual speech processing between ASD and healthy controls (HC) in the auditory cortex. The temporal dynamics of these differences still need to be characterized. Thus, in the present study we examined 14 adult subjects with high-functioning ASD and 15 adult HC while they viewed visual (lip movements) and auditory (voice) speech information that was either superimposed by white noise (condition 1) or not (condition 2). Subject's performance was quantified by measuring stimulus comprehension. In addition, event-related brain potentials (ERPs) were recorded. Results demonstrated worse speech comprehension for ASD subjects compared to HC under noisy conditions. Moreover, ERP-analysis revealed significantly higher P2 amplitudes over parietal electrodes for ASD subjects compared to HC.

Sex differences in a transgenic rat model of Huntington's disease: decreased 17beta-estradiol levels correlate with reduced numbers of DARPP32+ neurons in males.

Recent clinical studies have highlighted that female sex hormones represent potential neuroprotective mediators against damage caused by acute and chronic brain diseases. This evidence has been confirmed by experimental studies documenting the protective role of female sex hormones both in vitro and in vivo, although these studies did not specifically focus on Huntington's disease (HD). We therefore investigated the onset and course of HD in female and male transgenic (tg) HD (CAG(n51)) and control rats across age and focused on three aspects: (i) behavioral and physiological alterations (energy expenditure, home-cage activity, emotional disturbance and motor dysfunction), (ii) morphological markers (numbers and characteristics of striatal DARPP32(+) medium-sized spiny neurons (MSNs) and dopamine receptor autoradiography) and (iii) peripheral sex hormone levels as well as striatal estrogen receptor expression. Independent of their sex, tgHD rats exhibited increased levels of food intake, elevated home-cage activity scores and anxiolytic-like behavior, whereas only males showed an impairment of motor function. In line with the latter finding, loss and atrophy of DARPP32(+) MSNs were apparent only in male tgHD rats. This result was associated with a decreased striatal dopamine D1 receptor density and lower plasma levels of 17beta-estradiol at the age of 14 months. As DARPP32(+) MSNs expressed both alpha- and beta-estrogen receptors and showed a correlation between cell numbers and 17beta-estradiol levels, our findings suggest sex-related differences in the HD phenotype pointing to a substantial neuroprotective effect of sex hormones and opening new perspectives on the therapy of HD.

Inhibition of CD26/dipeptidyl peptidase IV enhances CCL11/eotaxin-mediated recruitment of eosinophils in vivo.

Chemokines mediate the recruitment of leukocytes to the sites of inflammation. N-terminal truncation of chemokines by the protease dipeptidyl peptidase IV (DPPIV) potentially restricts their activity during inflammatory processes such as allergic reactions, but direct evidence in vivo is very rare. After demonstrating that N-terminal truncation of the chemokine CCL11/eotaxin by DPPIV results in a loss of CCR3-mediated intracellular calcium mobilization and CCR3 internalization in human eosinophils, we focused on the in vivo role of CCL11 and provide direct evidence for specific kinetic and rate-determining effects by DPPIV-like enzymatic activity on CCL11-mediated responses of eosinophils. Namely, it is demonstrated that i.v. administration of CCL11 in wild-type F344 rats leads to mobilization of eosinophils into the blood, peaking at 30 min. This mobilization is significantly increased in DPPIV-deficient F344 rats. Intradermal administration of CCL11 is followed by a dose-dependent recruitment of eosinophils into the skin and is significantly more effective in DPPIV-deficient F344 mutants as well as after pharmacological inhibition of DPPIV. Interestingly, CCL11 application leads to an up-regulation of DPPIV, which is not associated with negative feedback inhibition via DPPIV-cleaved CCL11((3-74)). These findings demonstrate regulatory effects of DPPIV for the recruitment of eosinophils. Furthermore, they illustrate that inhibitors of DPPIV have the potential to interfere with chemokine-mediated effects in vivo including but not limited to allergy.

Postnatal morphological lung development of wild type and CD26/DPP4 deficient rat pups in dependency of LPS exposure.

BACKGROUND: Rodents are born with morphological immature lungs and an intact surfactant system. CD26/DPP4 is a multifactorial transmembrane integral type II protein, which is involved in physiological and pathophysiological processes and is already expressed during development. CD26/DPP4, called CD26 in the following, is able to enhance or dampen differently triggered inflammation. LPS exposure often used to simulate perinatal infection delays lung development. OBJECTIVE: A perinatal LPS rat model was used to test the hypothesis that CD26 deficiency modulates LPS-induced retardation in morphological lung development. METHODS: New born Fischer CD26 positive (CD26+) and deficient (CD26-) rats were exposed to LPS on postnatal day (day post partum, dpp) 3 and 5. Morphological parameters of lung development were determined stereologically. Lung development was analysed in 7, 10 14 and 21day old rats. RESULTS: Compared to controls LPS application resulted (1) in a mild inflammation independent of the strain, (2) in significantly lower total surface and volume of alveolar septa combined with significantly higher total volume of airspaces and alveolar size on dpp 7 in both substrains. However, compared to controls in LPS treated CD26- rats significant lower values of total septal surface and volume combined with higher values of total parenchymal airspaces and alveolar size were found until the end of classical alveolarization (dpp14). In LPS treated CD26+ rat pups the retardation was abolished already on dpp 10. CONCLUSION: In absence of CD26, LPS enhances the delay of morphological lung development. Morphological recovery was slower after the end of LPS exposure in CD26 deficient lungs.

Antimicrobial peptides in patients with anorexia nervosa: comparison with healthy controls and the impact of weight gain.

Clinical observations show that patients with anorexia nervosa (AN) are surprisingly free from infectious diseases. There is evidence from studies in Drosophila melanogaster that starvation leads to an increased expression of antimicrobial peptides (AMPs). AMPs are part of the innate immune system and protect human surfaces from colonization with pathogenic bacteria, viruses and fungi. We compared the expression of AMPs between patients with AN and healthy controls (HC) and investigated the influence of weight gain. Using a standardized skin rinsing method, quantitative determination of the AMPs psoriasin and RNase 7 was carried out by ELISA. Even though non-significant, effect sizes revealed slightly higher AMP concentrations in HC. After a mean weight gain of 2.0 body mass index points, the concentration of psoriasin on the forehead of patients with AN increased significantly. We could not confirm our hypotheses of higher AMP concentrations in patients with AN that decrease after weight gain. On the contrary, weight gain seems to be associated with increasing AMP concentrations.

Major inconsistencies of inferred population genetic structure estimated in a large set of domestic horse breeds using microsatellites.

STRUCTURE remains the most applied software aimed at recovering the true, but unknown, population structure from microsatellite or other genetic markers. About 30% of structure-based studies could not be reproduced (Molecular Ecology, 21, 2012, 4925). Here we use a large set of data from 2,323 horses from 93 domestic breeds plus the Przewalski horse, typed at 15 microsatellites, to evaluate how program settings impact the estimation of the optimal number of population clusters K opt that best describe the observed data. Domestic horses are suited as a test case as there is extensive background knowledge on the history of many breeds and extensive phylogenetic analyses. Different methods based on different genetic assumptions and statistical procedures (dapc, flock, PCoA, and structure with different run scenarios) all revealed general, broad-scale breed relationships that largely reflect known breed histories but diverged how they characterized small-scale patterns. structure failed to consistently identify K opt using the most widespread approach, the ΔK method, despite very large numbers of MCMC iterations (3,000,000) and replicates (100). The interpretation of breed structure over increasing numbers of K, without assuming a K opt, was consistent with known breed histories. The over-reliance on K opt should be replaced by a qualitative description of clustering over increasing K, which is scientifically more honest and has the advantage of being much faster and less computer intensive as lower numbers of MCMC iterations and repetitions suffice for stable results. Very large data sets are highly challenging for cluster analyses, especially when populations with complex genetic histories are investigated.

Eosinophil granulocytes: functional differences of a new isolation kit compared to the isolation with anti-CD16-conjugated MicroBeads.

BACKGROUND/PURPOSE: Using a new eosinophil isolation kit, we were not able to confirm our previous findings of a delayed apoptosis of eosinophils in atopic dermatitis. Thus, we investigated whether this new isolation kit modulates the functional activity of eosinophils. METHODS: Peripheral blood eosinophils were isolated with the new isolation kit as well as conventionally with anti-CD16-conjugated MicroBeads. We analysed viability, apoptosis, CD69 and CD95 expression, streptavidin binding and superoxide anion release. RESULTS: Purity of eosinophils was higher using the new isolation kit (P < 0.05). However, these eosinophils had a decreased survival (P < 0.05-0.01), presented morphological features of apoptosis, showed an increased percentage of apoptotic nuclei (P < 0.01), an increased release of superoxide anions (P < 0.05), a higher expression of CD69 and CD95 (P < 0.05) and an increased binding to streptavidin compared to eosinophils isolated with anti-CD16 conjugated MicroBeads. CONCLUSION: The new eosinophil isolation kit should not be used for the investigation of eosinophils as it potently affects their functional activity.

Differential severity of LPS-induced lung injury in CD26/DPP4 positive and deficient F344 rats.

BACKGROUND: Lipopolysaccharide (LPS) induced inflammation often leads to lung injury, in which pulmonary recruitment of neutrophils plays a pivotal role. Inflammatory processes are influenced by CD26/DPP4, highly expressed in lungs. Asthma induced CD26/DPP4 deficient (CD26/DPP4⁻) Fischer (F) 344 rats suffering from a transport block in the rER caused by a point mutation showed reduced pulmonary inflammation and reduced expression of immunomodulating surfactant proteins (SP). The degree of LPS induced lung injury in CD26/DPP4 deficient rats has not been investigated so far. OBJECTIVE: We hypothesize that LPS induced lung injury leads not only to an attenuated inflammation but also to a reduced SP expression and decreased structural damage in CD26/DPP4⁻ rats. METHODS: Both genotypes were intratracheally instilled with 250 µl LPS or with 250 µl 0.9% NaCl. Nine hours later animals were killed and either bronchoalveolar lavage was carried out to determine inflammatory cells and surface tension or lung blocks were removed and processed for histology, immunohistochemistry, electron microscopy or qRt-PCR analyses and Western Blot analyses. RESULTS: Signs of acute lung injury, such as structural damage of the blood gas barrier occurred only sporadically in both genotypes. LPS-induced CD26/DPP4⁻ rats showed decreased gene expression of SP-A and SP-D and reduced signs of lung inflammation associated with a reduced alveolar influx of macrophages and neutrophils. CONCLUSIONS: Less pulmonary inflammation combined with less structural alterations and minor expression of immunomodulating SP may be an indication of the critical role of CD26/DPP4 in regulating lung inflammation.