Transcriptional Dysregulation and Impaired Neuronal Activity in FMR1 Knock-Out and Fragile X Patients' iPSC-Derived Models

Fragile X syndrome (FXS) is caused by a repression of the FMR1 gene that codes the Fragile X mental retardation protein (FMRP), an RNA binding protein involved in processes that are crucial for proper brain development. To better understand the consequences of the absence of FMRP, we analyzed gene expression profiles and activities of cortical neural progenitor cells (NPCs) and neurons obtained from FXS patients' induced pluripotent stem cells (IPSCs) and IPSC-derived cells from FMR1 knock-out engineered using CRISPR-CAS9 technology. Multielectrode array recordings revealed in FMR1 KO and FXS patient cells, decreased mean firing rates; activities blocked by tetrodotoxin application. Increased expression of presynaptic mRNA and transcription factors involved in the forebrain specification and decreased levels of mRNA coding AMPA and NMDA subunits were observed using RNA sequencing on FMR1 KO neurons and validated using quantitative PCR in both models. Intriguingly, 40% of the differentially expressed genes were commonly deregulated between NPCs and differentiating neurons with significant enrichments in FMRP targets and autism-related genes found amongst downregulated genes. Our findings suggest that the absence of FMRP affects transcriptional profiles since the NPC stage, and leads to impaired activity and neuronal differentiation over time, which illustrates the critical role of FMRP protein in neuronal development.

CRISPR-clear imaging of melanin-rich B16-derived solid tumors

Tissue clearing combined with deep imaging has emerged as a powerful technology to expand classical histological techniques. Current techniques have been optimized for imaging sparsely pigmented organs such as the mammalian brain. In contrast, melanin-rich pigmented tissue, of great interest in the investigation of melanomas, remains challenging. To address this challenge, we have developed a CRISPR-based gene editing approach that is easily incorporated into existing tissue-clearing workflows such the PACT clearing method. We term this method CRISPR-Clear. We demonstrate its applicability to highly melanin-rich B16-derived solid tumors, including one made transgenic for HER2, constituting one of very few syngeneic mouse tumors that can be used in immunocompetent models. We demonstrate the utility in detailed tumor characterization by staining for targeting antibodies and nanoparticles, as well as expressed fluorescent proteins. With CRISPR-Clear we have unprecedented access to optical interrogation in considerable portions of intact melanoma tissue for stained surface markers, expressed fluorescent proteins, of subcellular compartments, and of the vasculature.

Can Google Trends analysis confirm the public's need for information about the rare association of facial nerve paralysis with COVID-19 or the COVID-19 vaccination?

Facial nerve paralysis or Bell's palsy have been suggested as possible consequences of SARS-CoV-2 infections, as well as possible side effects of COVID-19 vaccinations. Google Trends data have been used to evaluate worldwide levels of public awareness for these topics for pre- and post-pandemic years. The results demonstrate a relatively low public interest in facial nerve paralysis in comparison to other more common COVID-19 related topics. Some peaks of interest in Bell's palsy can most likely be explained as triggered by the media. Therefore, Google Trends has shown public's relatively low awareness of this rare neurological phenomenon during the pandemic.

Combining treatment for chronic hepatitis C with opioid agonist therapy is an effective microelimination strategy for people who inject drugs with high risk of non-adherence to antiviral therapy

Background & aims

Despite effective direct-acting antivirals (DAAs), hepatitis C virus (HCV) prevalence is high among people who inject drugs (PWIDs) and non-adherence to therapy remains a major obstacle towards HCV elimination in this subpopulation. To overcome this issue, we have combined ongoing opioid agonist therapy (OAT) with DAAs in a directly-observed therapy (DOT) setting.

Method

From September 2014 until January 2021 PWIDs at high risk of non-adherence to DAA therapy, who were also on OAT, were included into this microelimination project. Individuals received their OAT and DAAs under supervision of healthcare workers as DOT in a pharmacy or low-threshold facility.

Results

In total, 504 HCV RNA-positive PWIDs on OAT (387 men, 76.8%; median age: 38 years [IQR 33-45], HIV: 4.6%; hepatitis B: 1.4%) were included into this study. Two thirds reported ongoing intravenous drug use (IDU) and half of them had no permanent housing. Only 41 (8.1%) were lost to follow-up and two (0.4%) died of reasons unrelated to DAA toxicity. Overall, 90.7% of PWIDs achieved sustained virological response 12 weeks after treatment (SVR12) (95% CI: 88.1-93.2%). By excluding those lost to follow-up and hose who had died of causes unrelated to DAAs, the SVR12 rate was 99.1% (95% CI: 98.3-100.0%; modified intention-to-treat analysis). Four PWIDs (0.9%) experienced treatment failure. Over a median follow-up of 24 weeks (IQR 12-39), 27 reinfections (5.9%) were observed in individuals with the highest IDU rates (81.2%). Importantly, even though some were lost to follow-up, all completed their DAA treatment. By using DOT, adherence to DAAs was excellent with only a total of 86 missed doses (0.3% of 25,224 doses).

Conclusions

In this difficult-to-treat population of PWIDs with high rates of IDU , coupling DAA treatment to OAT in a DOT setting resulted in high SVR12 rates equivalent to conventional treatment settings in non-PWID populations.

Liver Assessment in Patients with Ataxia-Telangiectasia: Transient Elastography Detects Early Stages of Steatosis and Fibrosis

Background

Ataxia-telangiectasia (A-T) is a rare autosomal-recessive multisystem disorder characterized by pronounced cerebellar ataxia, telangiectasia, cancer predisposition, and altered body composition. Liver diseases with steatosis, fibrosis, and hepatocellular carcinoma are frequent findings in older patients but sensitive noninvasive diagnostic tools are lacking.

Objectives

To determine the sensitivity of transient elastography (TE) as a screening tool for early hepatic tissue changes and serum biomarkers for liver disease.

Methods

Thirty-one A-T patients aged 2 to 25 years were examined prospectively from 2016-2018 by TE. In addition, we evaluated the diagnostic performance of liver biomarkers for steatosis and necroinflammatory activity (SteatoTest and ActiTest, Biopredictive, Paris) compared to TE. For calculation and comparison, patients were divided into two groups (<12, >12 years of age).

Results

TE revealed steatosis in 2/21 (10%) younger patients compared to 9/10 (90%) older patients. Fibrosis was present in 3/10 (30%) older patients as assessed by TE. We found a significant correlation of steatosis with SteatoTest, alpha-fetoprotein (AFP), HbA1c, and triglycerides. Liver stiffness correlated significantly with SteatoTest, ActiTest, HbA1c, and triglycerides.

Conclusion

Liver disease is a common finding in older A-T patients. TE is an objective measure to detect early stages of steatosis and fibrosis. SteatoTest and ActiTest are a good diagnostic assessment for steatosis and necroinflammatory activity in patients with A-T and confirmed the TE results.

Comparative transcriptome analysis of inner blood-retinal barrier and blood-brain barrier in rats

Although retinal microvessels (RMVs) and brain microvessels (BMVs) are closely related in their developmental and share similar blood-neural barriers, studies have reported markedly different responses to stressors such as diabetes. Therefore, we hypothesized that RMVs and BMVs will display substantial differences in gene expression levels even though they are of the same embryological origin. In this study, both RMVs and BMVs were mechanically isolated from rats. Full retinal and brain tissue samples (RT, BT) were collected for comparisons. Total RNA extracted from these four groups were processed on Affymetrix rat 2.0 microarray Chips. The transcriptional profiles of these tissues were then analyzed. In the present paper we looked at differentially expressed genes (DEGs) in RMVs (against RT) and BMVs (against BT) using a rather conservative threshold value of ≥  ± twofold change and a false discovery rate corrected for multiple comparisons (p < 0.05). In RMVs a total of 1559 DEGs were found, of which 1004 genes were higher expressed in RMVs than in RT. Moreover, 4244 DEGs between BMVs and BT were identified, of which 1956 genes were ≥ twofold enriched in BMVs. Using these DEGs, we comprehensively analyzed the actual expression levels and highlighted their involvement in critical functional structures in RMVs and BMVs, such as junctional complex, transporters and signaling pathways. Our work provides for the first time the transcriptional profiles of rat RMVs and BMVs. These results may help to understand why retina and brain microvasculature show different susceptibilities to stressors, and they might even provide new insight for pharmacological interventions.

Neurofilament Light Chain Is a Biomarker of Neurodegeneration in Ataxia Telangiectasia

Ataxia telangiectasia (A-T) is a progressive and life-limiting disease associated with cerebellar ataxia due to progressive cerebellar degeneration. In addition to ataxia, which is described in detail, the presence of chorea, dystonia, oculomotor apraxia, athetosis, parkinsonism, and myoclonia are typical manifestations of the disease. The study aimed to evaluate the specificity and sensitivity of neurofilament light chain (NfL) as a biomarker of neurodegeneration in relation to SARA score. In this prospective trial, one visit of 42 A-T patients aged 1.3–25.6 years (mean 11.6 ± 7.3 years) was performed, in which NfL was determined from serum by ELISA. Additionally, a neurological examination of the patients was performed. Blood was collected from 19 healthy volunteers ≥ 12 years of age. We found significantly increased levels of NfL in patients with A-T compared to healthy controls (21.5 ± 3.6 pg/mL vs. 9.3 ± 0.49 pg/mL, p ≤ 0.01). There was a significant correlation of NfL with age, AFP, and SARA. NfL is a new potential progression biomarker in blood for neurodegeneration in A-T which increases with age.

Role of soluble guanylyl cyclase in renal afferent and efferent arterioles

Renal arteriolar tone depends considerably on the dilatory action of nitric oxide (NO) via activation of soluble guanylyl cyclase (sGC) and cGMP action. NO deficiency and hypoxia/reoxygenation are important pathophysiological factors in the development of acute kidney injury. It was hypothesized that the NO-sGC-cGMP system functions differently in renal afferent arterioles (AA) compared with efferent arterioles (EA) and that the sGC activator cinaciguat differentially dilates these arterioles. Experiments were performed in isolated, perfused mouse glomerular arterioles. Hypoxia (0.1% oxygen) was achieved by using a hypoxia chamber. Phosphodiesterase 5 (PDE5) and sGC subunits were considerably expressed on the mRNA level in AA. PDE5 inhibition with sildenafil, which blocks cGMP degradation, diminished the responses to ANG II bolus application in AA, but not significantly in EA. Vasodilation induced by sildenafil in ANG II-preconstricted vessels was stronger in EA than AA. Cinaciguat, an NO- and heme-independent sGC activator, dilated EA more strongly than AA after N^G-nitro-l-arginine methyl ester (l-NAME; NO synthase inhibitor) treatment and preconstriction with ANG II. Cinaciguat-induced dilatation of l-NAME-pretreated and ANG II-preconstricted arterioles was similar to controls without l-NAME treatment. Cinaciguat also induced dilatation in iodinated contrast medium treated AA. Furthermore, it dilated EA, but not AA, after hypoxia/reoxygenation. The results reveal an important role of the NO-sGC-cGMP system for renal dilatation and that EA have a more potent sGC activated dilatory system. Furthermore, AA seem to be more sensitive to hypoxia/reoxygenation than EA under these experimental conditions.

Oil supplementation with a special combination of n-3 and n-6 long-chain polyunsaturated fatty acids does not protect for exercise induced asthma: a double-blind placebo-controlled trial

BACKGROUND

Many patients suffering from exercise-induced asthma (EIA) have normal lung function at rest and show symptoms and a decline in FEV₁ when they do sports or during exercise-challenge. It has been described that long-chain polyunsaturated fatty acids (LCPUFA) could exert a protective effect on EIA.

METHODS

In this study the protective effect of supplementation with a special combination of n-3 and n-6 LCPUFA (sc-LCPUFA) (total 1.19 g/ day) were investigated in an EIA cold air provocation model.

PRIMARY OUTCOME MEASURE

Decrease in FEV₁ after exercise challenge and secondary outcome measure: anti-inflammatory effects monitored by exhaled NO (eNO) before and after sc-LCPUFA supplementation versus placebo.

RESULTS

Ninety-nine patients with exercise-induced symptoms aged 10 to 45 were screened by a standardized exercise challenge in a cold air chamber at 4 °C. Seventy-three patients fulfilled the inclusion criteria of a FEV₁ decrease > 15% and were treated double-blind placebo-controlled for 4 weeks either with sc-LCPUFA or placebo. Thirty-two patients in each group completed the study. Mean FEV₁ decrease after cold air exercise challenge and eNO were unchanged after 4 weeks sc-LCPUFA supplementation.

CONCLUSION

Supplementation with sc-LCPUFA at a dose of 1.19 g/d did not have any broncho-protective and anti-inflammatory effects on EIA.

TRIAL REGISTRATION

Clinical trial registration number: NCT02410096. Registered 7 February 2015 at Clinicaltrial.gov.

Kin discrimination in social yeast is mediated by cell surface receptors of the Flo11 adhesin family

Microorganisms have evolved specific cell surface molecules that enable discrimination between cells from the same and from a different kind. Here, we investigate the role of Flo11-type cell surface adhesins from social yeasts in kin discrimination. We measure the adhesion forces mediated by Flo11A-type domains using single-cell force spectroscopy, quantify Flo11A-based cell aggregation in populations and determine the Flo11A-dependent segregation of competing yeast strains in biofilms. We find that Flo11A domains from diverse yeast species confer remarkably strong adhesion forces by establishing homotypic interactions between single cells, leading to efficient cell aggregation and biofilm formation in homogenous populations. Heterotypic interactions between Flo11A domains from different yeast species or Saccharomyces cerevisiae strains confer weak adhesive forces and lead to efficient strain segregation in heterogenous populations, indicating that in social yeasts Flo11A-mediated cell adhesion is a major mechanism for kin discrimination at species and sub-species levels. These findings, together with our structure and mutation analysis of selected Flo11A domains, provide a rationale of how cell surface receptors have evolved in microorganisms to mediate kin discrimination.

A combination of LCPUFA ameliorates airway inflammation in asthmatic mice by promoting pro-resolving effects and reducing adverse effects of EPA

Lipid mediators derived from omega (n)-3 and n-6 long-chain polyunsaturated fatty acids (LCPUFA) play key roles in bronchoconstriction, airway inflammation, and resolution processes in asthma. This study compared the effects of dietary supplementation with either a combination of LCPUFAs or eicosapentaenoic acid (EPA) alone to investigate whether the combination has superior beneficial effects on the outcome of asthmatic mice. Mice were sensitized with house dust mite (HDM) extract, and subsequently supplemented with either a combination of LCPUFAs or EPA alone in a recall asthma model. After the final HDM and LCPUFA administration, airway hyperresponsiveness (AHR), bronchoalveolar lavages, and lung histochemistry were examined. Lipid mediator profiles were determined by liquid chromatography coupled with tandem mass spectrometry (LC-MS-MS). The LCPUFA combination reduced AHR, eosinophilic inflammation, and inflammatory cytokines (IL-5, IFN-γ, and IL-6) in asthmatic mice, whereas EPA enhanced inflammation. The combination of LCPUFAs was more potent in downregulating EPA-derived LTB₅ and LTC₅ and in supporting DHA-derived RvD1 and RvD4 (2.22-fold and 2.58-fold higher levels) than EPA alone. Ex vivo experiments showed that LTB₅ contributes to granulocytes' migration and M1-polarization in monocytes. Consequently, the LCPUFA combination ameliorated airway inflammation by inhibiting adverse effects of EPA and promoting pro-resolving effects supporting the lipid mediator-dependent resolution program.

A combination of LCPUFAs regulates the expression of miRNA-146a-5p in a murine asthma model and human alveolar cells

BACKGROUND

LCPUFAs are suggestive of having beneficial effects on inflammatory diseases such as asthma. However, little is known about the modulative capacity of omega-(n)-3 and n-6 LCPUFAs within the epigenetic regulation of inflammatory processes.

OBJECTIVE

The aim of this study was to investigate whether a specific combined LCPUFA supplementation restores disease-dysregulated miRNA-profiles in asthmatic mice. In addition, we determined the effect of the LCPUFA supplementation on the interaction of the most regulated miRNA expression and oxygenase activity in vitro.

METHODS

Sequencing of miRNA was performed by NGS from lung tissue of asthmatic and control mice with normal diet, as well as of LCPUFA supplemented asthmatic mice. Network analysis and evaluation of the biological targets of the miRNAs were performed by DIANA- miRPath v.3 webserver software, TargetScanMouse 7.2, and tool String v.10, respectively. Expression of hsa-miRNA-146a-5p and activity of COX-2 and 5-LO in LCPUFA-treated A549 cells were assessed by qPCR and flow cytometry, respectively.

RESULTS

In total, 62 miRNAs were dysregulated significantly in murine allergic asthma. The LCPUFA combination restored 21 of these dysregulated miRNAs, of which eight (mmu-miR-146a-5p, -30a-3p, -139-5p, -669p-5p, -145a-5p, -669a-5p, -342-3p and -15b-5p) were even normalized compared to the control levels. Interestingly, six of the eight rescued miRNAs are functionally implicated in TGF-β signaling, ECM-receptor interaction and fatty acid biosynthesis. Furthermore, in vitro experiments demonstrated that upregulation of hsa-miRNA-146a-5p is accompanied by a reduction of COX-2 and 5-LO activity. Moreover, transfection experiments revealed that LCPUFAs inhibit 5-LO activity in the presence and absence of anti-miR-146a-5p.

CONCLUSION

Our results demonstrate the modulative capacity of LCPUFAs on dysregulated miRNA expression in asthma. In addition, we pointed out the high regulative potential of LCPUFAs on 5-LO regulation and provided evidence that miR-146a partly controls the regulation of 5-LO.

How to evaluate effects of occupational therapy - lessons learned from an exploratory randomized controlled trial

BACKGROUND

Although occupational therapy (OT) is frequently prescribed in clinical practice, there is still insufficient evidence regarding its efficacy to improve Parkinson's Disease (PD)-related activity limitations.

OBJECTIVES

To evaluate the efficacy of OT and the validity of different outcome-parameters to reflect efficacy, including gold-standard clinical rating scales and quantitative motor assessments.

METHODS

40 patients were included in an exploratory, randomized-controlled, single-blinded trial, receiving either (I) ten weeks of OT, with a main focus on motor aspects of activity limitations and a ten-week follow-up assessment or (II) no intervention. Inclusion criteria were diagnosis of PD and Hoehn & Yahr stage 2-3. Patients with major depression, other neurological or orthopedic diseases or OT beforehand were excluded from the study. To monitor treatment effects the MDS-UPDRS part II and III were used for patient- and clinician-based assessment. Objective Pegboard as well as Q-Motor "tremormotography" and "digitomotography" were applied.

RESULTS

The interventional group reported a subjective amelioration of activity limitations, with a significant improvement of MDS-UPDRS part II at the end of the study (p = 0.030). However, clinician's rating and quantitative motor assessment failed to detect a significant improvement of motor impairment and fine motor control.

CONCLUSIONS

This study goes in line with previous trials, showing an individual improvement of activity limitations from the patients' point of view. The discrepancy between self-perception, focusing on activity limitation, and clinician-based rating, focusing on motor impairment, challenges the current gold standard assessments as valid outcome parameters for occupational therapy trials aiming for an individualized improvement of disease burden.

Rational manufacturing of functionalized, long-term stable perfluorocarbon-nanoemulsions for site-specific 19F magnetic resonance imaging

BACKGROUND

Perfluorocarbon (PFC)-nanoemulsions (NE) are a convenient tool for ¹⁹F magnetic resonance imaging in cell and animal experiments. Typical preparation methods, like high-pressure homogenization or microfluidization, produce nanoemulsions in mL-scale. However, experiments usually require only miniscule amounts of PFC-NE, several 100 µL. For site-specific imaging tissue-specific ligands, e.g. peptides or antibodies, are covalently bound to the NE surface. This requires the use of expensive functionalized phospholipids containing reactive groups (e.g. maleimide), which often deteriorate quickly in liquid storage, rendering the manufacturing process highly cost-inefficient. A technique to manufacture storage stable NE that maintain their functionality for coupling of various ligands is desired.

METHODS AND RESULTS

Different PFC-NE formulations and preparation techniques were compared and the most suitable of these was tested in short-, as well as long-term stability tests. Droplet size stability was investigated by dynamic light scattering and cryogenic transmission electron microscopy over 1.5 a. Surface modifiability was assessed by a fluorescence assay. The utility of these NE was proven in an in vitro model.

CONCLUSION

The established PFC-NE platform offers a cost-efficient way to produce larger amounts of long-term storable imaging agents, which can be surface-modified on demand for application in targeted ¹⁹F MRI.

Lungenfunktion, Lung Clearance Index und bronchiale Entzündung bei Kindern und Jugendlichen mit Bronchiolitis obliterans

Einleitung Die Bronchiolitis obliterans (BO) ist eine sehr seltene, chronische Lungenerkrankung, die vereinzelt nach schweren Atemwegsinfektionen oder als Folge von Stammzell- und Lungentransplantation auftritt. Ziel der Arbeit war es, die Lungenfunktion und die bronchiale Entzündung bei BO-Patienten im Jugend- und Kindesalter zu untersuchen. Zudem sollte das Potenzial des LCI in der Diagnostik dieser Patienten untersucht werden.

Methoden Es wurden 16 BO-Patienten (Alter: Median 16,7; 9,6 – 25,3 Jahre) und 17 gesunde Probanden (Alter: Median 16,6; 7,6 – 25,0 Jahre) untersucht. Neben der Untersuchung der Lungenfunktion (FVC, FEV1, MEF25, RV und RV/TLC) mittels Bodyplethysmografie erfolgte eine Reversibilitätstestung nach Gabe von 400 µg Salbutamol. Die Bestimmung des LCI erfolgte mittels Multiple Breath Washout (MBW)-Methode. Zusätzlich wurde die Zellverteilung und das Zytokinprofil (IL-1ß, IL-6, IL-8, TNF-α) mittels Cytometric Bead Array (CBA) im induzierten Sputum analysiert.

Ergebnisse FVC, FEV1 und MEF25 der BO-Patienten waren signifikant niedriger, das RV und die RV/TLC jedoch signifikant erhöht im Vergleich zur Kontrollgruppe. Eine bronchiale Reversibilität zeigte sich bei 3 Patienten. Der LCI war bei den BO-Patienten gegenüber der Kontrollgruppe signifikant erhöht (Median 10,24 vs. 7,1) und korrelierte signifikant mit dem MEF25 (p < 0,0001). Im induzierten Sputum fand sich eine signifikante Erhöhung der Gesamtzellzahl, der neutrophilen Granulozyten sowie von IL-6 und IL-8 (p < 0.01).

Schlussfolgerung Die Lungenfunktion ist bei Kindern und Jugendlichen mit BO stark eingeschränkt. Zudem erwies sich der LCI als sensitiver und reproduzierbarer Marker zur Beurteilung der obstruktiven Beeinträchtigung der kleinen Atemwege. Im induzierten Sputum ist eine von Neutrophilen dominierte bronchiale Entzündung nachweisbar.

A specific combined long-chain polyunsaturated fatty acid supplementation reverses fatty acid profile alterations in a mouse model of chronic asthma

Background

The immune-modulating potential of long-chain polyunsaturated fatty acids (LCPUFAs) based on their conversion into lipid mediators in inflammatory situations has been proven by several studies. Respecting the immune-modulative role of lipid mediators in bronchoconstriction, airway inflammation and resolution of inflammatory processes, LCPUFAs play an important role in asthma. To design a disease-specific and most beneficial LCPUFA supplementation strategy, it is essential to understand how asthma alters LCPUFA profiles. Therefore, this study characterizes the alterations of LCPUFA profiles induced by allergic asthma. In addition, this study explores whether a simple eicosapentaenoic acid (EPA) alone or a specific combined LCPUFA supplementation could restore imbalanced LCPUFA profiles.

Methods

Mice were sensitized with a daily dose of 40 μg house dust mite (HDM)-extract in a recall model and fed with either normal diet, EPA or a specific combined (sc)-LCPUFA supplementation containing EPA, docosahexaenoic acid (DHA), γ -linolenic acid (GLA) and stearidonic acid (SDA) for 24 days. After recall with HDM, mice were sacrificed and blood and lung tissue were collected. Fatty acid profiles were determined in plasma, blood cells and lung cells of asthmatic mice by capillary gas-chromatography.

Results

In lung cells of asthmatic mice, arachidonic acid (AA, p < 0.001) and DHA (p < 0.01) were increased while dihomo-γ-linolenic acid (DGLA, p < 0.05) was decreased. EPA supplementation increased only EPA (p < 0.001) and docosapentaenoic acid (DPA, p < 0.001), but neither DGLA nor DHA in lung cells of asthmatic mice. In contrast, a specific combined dietary supplementation containing n-3 and n-6 LCPUFAs could decrease AA (p < 0.001), increase EPA (p < 0.001), DPA (p < 0.001) and DHA (p < 0.01) and could reverse the lack of DGLA (p < 0.05).

Conclusions

In summary, allergic asthma alters LCPUFA profiles in blood and lung tissue. In contrast to the EPA supplementation, the distinct combination of n-3 and n-6 LCPUFAs restored the LCPUFA profiles in lung tissue of asthmatic mice completely. Subsequently, sc-LCPUFA supplementation is likely to be highly supportive in limiting and resolving the inflammatory process in asthma.

Electronic supplementary material

The online version of this article (10.1186/s12944-018-0947-6) contains supplementary material, which is available to authorized users.

The involvement of phosphorylation of myosin phosphatase targeting subunit 1 (MYPT1) and MYPT1 isoform expression in NO/cGMP mediated differential vasoregulation of cerebral arteries compared to systemic arteries

AIM

Constitutive release of NO blunts intrinsic and stimulated contractile activity in cerebral arteries (CA). Here, we explored whether phosphorylation and expression levels of the PKG-sensitive, leucine zipper positive (LZ⁺ ) splice variants of the regulatory subunit of myosin phosphatase (MYPT1) are involved and whether its expression is associated with higher cGMP sensitivity.

METHODS

Vascular contractility was investigated by wire myography. Phosphorylation of MYPT1 was determined by Western blotting.

RESULTS

Constitutive phosphorylation of MYPT1-T696 and T853 was lower and that of S695 and S668 was higher in cerebral arteries from the circulus arteriosus (CA-w) than in femoral arteries (FA), while total MYPT1 expression was not different. In CA-w but not in FA, L-NAME lowered phosphorylation of S695/S668 and increased phosphorylation of T696/T853 and of MLC₂₀ -S19, plus basal tone. The increase in basal tone was attenuated in CA-w and basilar arteries (BA) from heterozygous MYPT1-T696A/+ mice. Compared to FA, expression of the LZ⁺ -isoform was ~2-fold higher in CA-w coincident with a higher sensitivity to DEA-NONOate, cinaciguat and Y27632 in BA and 8-Br-cGMP (1 μmol/L) in pre-constricted (pCa 6.1) α-toxin permeabilized CAs. In contrast, 6-Bnz-cAMP (10 μmol/L) relaxed BA and FA similarly by ~80%.

CONCLUSION

Our results indicate that (i) regulation of the intrinsic contractile activity in CA involves phosphorylation of MYPT1 at T696 and S695/S668, (ii) the higher NO/cGMP/PKG sensitivity of CAs can be ascribed to the higher expression level of the LZ⁺ -MYPT1 isoform and (iii) relaxation by cAMP/PKA pathway is less dependent on the expression level of the LZ⁺ splice variants of MYPT1.

Higher Ca2+ -sensitivity of arterial contraction in 1-week-old rats is due to a greater Rho-kinase activity

AIM

During early post-natal development, arterial contraction depends less on Ca²⁺ -signalling pathways but more on changes in Ca²⁺ -sensitivity compared to adult animals. Whether this difference is related to Rho-kinase, one of the major players affecting Ca²⁺ -sensitivity, is unknown for intact vessels. Thus, we tested the hypothesis that Rho-kinase critically contributes to the higher Ca²⁺ -sensitivity of contraction in intact arteries of 1-week-old rats.

METHODS

We studied 1-week-old, 4- to 5-week-old and 10- to 12-week-old rats performing isometric myography, Ca²⁺ -fluorimetry and Western blotting using intact saphenous arteries and arterial pressure measurements under urethane anaesthesia.

RESULTS

In 10- to 12-week-old rats, methoxamine (MX) produced vasoconstriction associated with an increase in [Ca²⁺ ]_i and Ca²⁺ -sensitivity. In contrast, in 1-week-old rats these contractions were accompanied only by an increase in Ca²⁺ -sensitivity. All MX-induced effects were reduced by the Rho-kinase inhibitor Y-27632; this reduction was complete only in 1-week-old rats. The Rho-kinase specific site Thr⁸⁵⁵ on MYPT1 was increasingly phosphorylated by MX in vessels of 1-week-old, but not 10- to 12-week-old rats; this effect was also inhibited completely by Y-27632. The Rho-kinase inhibitor fasudil in a dose not affecting the pressor response to MX in 4- to 5-week-old rats reduced it considerably in 1-week-old rats.

CONCLUSION

Our results suggest that the higher Ca²⁺ -sensitivity of arterial contraction in 1-week-old compared to 10- to 12-week-old rats is due to a greater Rho-kinase activity. Constitutively active Rho-kinase contributes to MX-induced contraction in 10- to 12-week-old rats. In 1-week-old rats, additional Rho-kinase activation is involved. This remodelling of the Rho-kinase pathway is associated with its increased contribution to adrenergic arterial pressure responses.

Directly observed therapy of chronic hepatitis C with ledipasvir/sofosbuvir in people who inject drugs at risk of nonadherence to direct-acting antivirals

An important subgroup of people who inject drugs (PWID) receiving opioid agonist therapy (OAT) cannot be treated in the setting of a hepatology centre and would not regularly ingest their medication when handed to them for self-administration. Our hypothesis was that chronic hepatitis C in these patients could be ideally managed if modern, interferon-free regimens were administered together with OAT under direct observation of a physician or nurse at a low-threshold facility. In this open-label, noninterventional, proof-of-concept study (ClinicalTrials.gov number, NCT02638233), 40 PWID at risk of nonadherence to direct-acting antivirals (DAA) and previously untreated chronic hepatitis C virus genotype 1 infection without cirrhosis were treated with ledipasvir/sofosbuvir for 8 weeks. Patients received antiviral treatment together with OAT under direct observation of a physician or nurse at a low-threshold facility. By following the concept of directly observed therapy, excellent adherence to antiviral therapy was achieved as follows: only 0.16% (95% CI: 0.03-0.47) of scheduled dates for ingestion of the antiviral therapy in combination with OAT were missed by the 40 patients. The rate of sustained virological response 12 weeks after end of therapy was 100% (95% CI: 91.2-100.0). Between week 12 and week 24 of follow-up reinfections were recorded in 2 of 40 patients (5%). Directly observed therapy of chronic hepatitis C is highly effective in PWID at risk of nonadherence to DAA. By this new concept, a group of difficult-to-treat patients can be cured, who could not have been treated in settings of studies published so far.

Medical Informatics and the Quality of Health: New Approaches to Support Patient Care

Objectives: The Yearbook of Medical Informatics is published annually by the International Medical Informatics Association (IMIA) and contains a selection of excellent papers on medical informatics research which have been recently published (www.yearbook.uni-hd.de). The 2003 Yearbook of Medical Informatics took as its theme the role of medical informatics for the quality of health care. In this paper, we will discuss challenges for health care, and the lessons learned from editing IMIA Yearbook 2003.

Results and Conclusions: Modern information processing methodology and information and communication technology have strongly influenced our societies and health care. As a consequence of this, medical informatics as a discipline has taken a leading role in the further development of health care. This involves developing information systems that enhance opportunities for global access to health services and medical knowledge. Informatics methodology and technology will facilitate high quality of care in aging societies, and will decrease the possibilities of health care errors. It will also enable the dissemination of the latest medical and health information on the web to consumers and health care providers alike. The selected papers of the IMIA Yearbook 2003 present clear examples and future challenges, and they highlight how various sub-disciplines of medical informatics can contribute to this.

A Realistic Model of Human Structure from the Visible Human Data

The computer-based 3D models of the human body reported to date suffer from poor spatial resolution. The Visible Human project has delivered high resolution cross-sectional images that are suited for generation of high-quality models. Yet none of the 3D models described to date reflect the quality of the original images. We present a method of segmentation and visualization which provides a new quality of realism and detail. Using the example of a 3D model of the inner organs, we demonstrate that such models, especially when combined with a knowledge base, open new possibilities for scientific, educational, and clinical work.

A Regional Health Care Network: eHealth.Braunschweig

Background: Health care network eHealth.Braunschweig has been started in the South-East region of Lower Saxony in Germany in 2009. It composes major health care players, participants from research institutions and important local industry partners.

Objectives: The objective of this paper is firstly to describe the relevant regional characteristics and distinctions of the eHealth.Braunschweig health care network and to inform about the goals and structure of eHealth.Braunschweig; secondly to picture and discuss the main concepts and domain fields which are addressed in the health care network; and finally to discuss the architectural challenges of eHealth.Braunschweig regarding the addressed domain fields and defined requirements.

Methods: Based on respective literature and former conducted projects we discuss the project structure and goals of eHealth.Braunschweig, depict major domain fields and requirements gained in workshops with participants and discuss the architectural challenges as well as the architectural approach of eHealth.Braunschweig network.

Results: The regional healthcare network eHealth.Braunschweig has been established in April 2009. Since then the network has grown constantly and a sufficient progress in network activities has been achieved. The main domain fields have been specified in different workshops with network participants and an architectural realization approach for the transinstitutional information system architecture in the healthcare network has been developed. However, the effects on quality of information processing and quality of patient care have not been proved yet. Systematic evaluation studies have to be done in future in order to investigate the impact of information and communication technology on the quality of information processing and the quality of patient care.

Conclusions: In general, the aspects described in this paper are expected to contribute to a systematic approach for the establishment of regional health care networks with lasting and sustainable effects on patient-centered health care in a regional context.

Reduzierung des Neorefluxes an der V. saphena magna Crosse durch extensive Crossektomie

Background: Neovascularisation (NV) at the saphenofemoral junction (SFJ) is an important cause of recurrent great saphenous varicose veins. Unfortunately up to now no surgical technique at the SFJ could prevent neoreflux completely. We present a new technique at the SFJ with the aim to reduce the rate of neoreflux.

Material and Methods: In a prospective study 100 patients (100 SFJ ligations) with extensive crossectomy were included. Extensive crossectomy means: Flush ligation of the SFJ, oversewing the endothelium stump with Prolene®(4 x 0), ligation of the side branches as far away as possible from the SFJ and electrocoagulation of the free endothelium of these side branches. Mean age 47 years (18–65), female/ male 69 %/31 %, ASA-classification I–II (100 %), CEAP-classification C2 59, C3 25, C4 16. All patients could be examined by colour duplex scan after two/three days, three months and one year and 68 patients after two years.

Results: Duplex imagines identified neoreflux at the SFJ in two patients (2 %) after one year and in only one patient (1.5 %/ 68 patients) after two years. This female patient was pregnant (31st week) and had recurrent varicose veins with origin mostly from an insufficient Dodd perforator vein. The other patient with reflux at the first examination showed no more reflux after two years.

Conclusion: Recurrent reflux in the groin by neovascularisation was strongly reduced by our technique of extensive crossectomy. Up to know no other technique to prevent NV (patch, barrier technique) has shown such favourable results. The technique is easily performed and has no further complication than a simple ligation of the SFJ.

Omalizumab effectively protects against early and late allergic responses in asthma after 4 weeks

BACKGROUND

Omalizumab is licensed for therapy in severe allergic asthma with an effect demonstrated after 8 weeks or longer treatment. As new applications for omalizumab demand precise knowledge of the onset of effects, the objective of this study was to determine the time course of the early (EAR) and late allergic reaction (LAR).

MATERIALS AND METHODS

Ten patients (IgE>300 IU/mL and <700 IU/mL) with a significant response to allergen challenge were treated with omalizumab according to the approved dosing table. Bronchial allergen provocations (BAP) were repeated at weeks 1, 2, 4, and 8.

RESULTS

EAR was significantly reduced after 4 weeks (ΔFEV1 28% vs 11%; P<.001), eNO (86 vs 53 ppb; P<.05) and basophil activation after 2 weeks (CD63 expression 79% vs 32%, P<.05) and LAR already after 1 week (ΔFEV1 26% vs 13%, P<.05).

CONCLUSION

These results demonstrate the onset of protective effects earlier than previously determined, potentially improving seasonal utilization and combination with immunotherapy.

Myoglobin facilitates angiotensin II-induced constriction of renal afferent arterioles

Vasoconstriction plays an important role in the development of acute kidney injury in rhabdomyolysis. We hypothesized that myoglobin enhances the angiotensin II (ANG II) response in afferent arterioles by increasing superoxide and reducing nitric oxide (NO) bioavailability. Afferent arterioles of C57Bl6 mice were isolated perfused, and vasoreactivity was analyzed using video microscopy. NO bioavailability, superoxide concentration in the vessel wall, and changes in cytosolic calcium were measured using fluorescence techniques. Myoglobin treatment (10−5 M) did not change the basal arteriolar diameter during a 20-min period compared with control conditions. NG-nitro-l-arginine methyl ester (l-NAME, 10−4 M) and l-NAME + myoglobin reduced diameters to 94.7 and 97.9% of the initial diameter, respectively. Myoglobin or l-NAME enhanced the ANG II-induced constriction of arterioles compared with control (36.6 and 34.2%, respectively, vs. 65.9%). Norepinephrine responses were not influenced by myoglobin. Combined application of myoglobin and l-NAME further facilitated the ANG II response (7.0%). Myoglobin or l-NAME decreased the NO-related fluorescence in arterioles similarly. Myoglobin enhanced the superoxide-related fluorescence, and tempol prevented this enhancement. Tempol also partly prevented the myoglobin effect on the ANG II response. Myoglobin increased the fura 2 fluorescence ratio (cytosolic calcium) during ANG II application (10−12 to 10−6 M). The results suggest that the enhanced afferent arteriolar reactivity to ANG II is mainly due to a myoglobin-induced increase in superoxide and associated reduction in the NO bioavailability. Signaling pathways for the augmented ANG II response include enhanced cytosolic calcium transients. In conclusion, myoglobin may contribute to the afferent arteriolar vasoconstriction in this rhabdomyolysis model.

Nanomechanical mapping of first binding steps of a virus to animal cells

Viral infection is initiated when a virus binds to cell surface receptors. Because the cell membrane is dynamic and heterogeneous, imaging living cells and simultaneously quantifying the first viral binding events is difficult. Here, we show an atomic force and confocal microscopy set-up that allows the surface receptor landscape of cells to be imaged and the virus binding events within the first millisecond of contact with the cell to be mapped at high resolution (<50 nm). We present theoretical approaches to contour the free-energy landscape of early binding events between an engineered virus and cell surface receptors. We find that the first bond formed between the viral glycoprotein and its cognate cell surface receptor has relatively low lifetime and free energy, but this increases as additional bonds form rapidly (≤1 ms). The formation of additional bonds occurs with positive allosteric modulation and the three binding sites of the viral glycoprotein are quickly occupied. Our quantitative approach can be readily applied to study the binding of other viruses to animal cells.

The biomechanical properties of an epithelial tissue determine the location of its vasculature

An important question is how growing tissues establish a blood vessel network. Here we study vascular network formation in pancreatic islets, endocrine tissues derived from pancreatic epithelium. We find that depletion of integrin-linked kinase (ILK) in the pancreatic epithelial cells of mice results in glucose intolerance due to a loss of the intra-islet vasculature. In turn, blood vessels accumulate at the islet periphery. Neither alterations in endothelial cell proliferation, apoptosis, morphology, Vegfa expression and VEGF-A secretion nor ‘empty sleeves' of vascular basement membrane are found. Instead, biophysical experiments reveal that the biomechanical properties of pancreatic islet cells, such as their actomyosin-mediated cortex tension and adhesive forces to endothelial cells, are significantly changed. These results suggest that a sorting event is driving the segregation of endothelial and epithelial cells and indicate that the epithelial biomechanical properties determine whether the blood vasculature invades or envelops a growing epithelial tissue.

Vasculature is denser in soft than in stiff tissues. Kragl et al. suggest a mechanistic link between biomechanical tissue properties and vascularization by showing that integrin-linked kinase reduces the contractile forces of the cell cortex in endocrine pancreatic cells, facilitating their adhesion to blood vessels and enabling pancreatic islet vascularization.

Diabetes converts arterial regulation by perivascular adipose tissue from relaxation into H(2)O(2)-mediated contraction

This study aims to reveal the reason for the increased force of 5-hydroxytryptamine-induced contraction of endothelium-denuded skeletal muscle arteries of diabetic rats in the presence of perivascular adipose tissue (PVAT). Our data on rat gracilis arteries show that i) PVAT of skeletal muscle arteries of healthy and diabetic rats releases hydrogen peroxide (H(2)O(2)), ii) higher concentrations of 5-hydroxytryptamine increase the production of H(2)O(2) in PVAT; iii) an enhanced PVAT production of H(2)O(2) is the main, if not the only, reason for the sensitization of arterial contraction to 5-hydroxytriptamine-induced contraction in diabetes and iv) endothelium antagonizes the effect of PVAT-derived H(2)O(2).

Body composition, muscle strength and hormonal status in patients with ataxia telangiectasia: a cohort study

Background

Ataxia-telangiectasia (A-T) is a devastating human autosomal recessive disorder that causes progressive cerebellar ataxia, immunodeficiency, premature aging, chromosomal instability and increased cancer risk. Affected patients show growth failure, poor weight gain, low body mass index (BMI), myopenia and increased fatigue during adolescence.

The prevalence of alterations in body composition, muscle strength and hormonal status has not been well described in classical A-T patients. Additionally, no current guidelines are available for the assessment and management of these changes.

Methods

We analyzed body composition, manual muscle strength and hormonal status in 25 A-T patients and 26 age-matched, healthy controls. Bioelectrical impedance analysis (BIA) was performed to evaluate the body composition, fat-free mass (FFM), body cell mass (BCM), extracellular matrix (ECM), phase angle (PhA), fat mass (FM) and ECM to BCM ratio. Manual muscle strength was measured using a hydraulic hand dynamometer.

Results

The BMI, FFM and PhA were significantly lower in A-T patients than in controls (BMI 16.56 ± 3.52 kg/m² vs. 19.86 ± 3.54 kg/m²; Z-Score: -1.24 ± 1.29 vs. 0.05 ± 0.92, p <0.001; FFM 25.4 ± 10.03 kg vs. 41.77 ± 18.25 kg, p < 0.001; PhA: 4.6 ± 0.58° vs. 6.15 ± 0.88°, p < 0.001). Manual muscle strength was significantly impaired in A-T patients compared with controls (10.65 ± 10.97 kg vs. 26.8 ± 30.39 kg, p < 0.0001). In addition, cortisol and dehydroepiandrosterone sulfate (DHEAS) levels were significantly lower in A-T patients than in controls.

Conclusion

Altered body composition, characterized by depleted BMI, PhA and BCM; by the need to sit in a wheelchair; by altered hormone levels; and by poor muscle strength, is a major factor underlying disease progression and increased fatigue in A-T patients.

Trial registration

ClinicalTrials.gov NCT02345200

Can we predict allergen-induced asthma in patients with allergic rhinitis?

BACKGROUND

A high percentage of patients with allergic rhinitis (AR) exhibit signs of bronchial hyperreactivity (BHR), and approximately 30% may develop asthma later in life.

OBJECTIVE

The aim of this study was to identify predictors for allergen-induced asthma in patients with AR.

METHODS

Hundred patients with AR selected by public posting and 20 healthy controls were enrolled. Twenty-three patients with concomitant physician-diagnosed asthma and four with a negative allergy test were excluded from further analysis. The remaining 73 subjects with AR underwent bronchial allergen provocation (BAP), which is considered the gold standard for the diagnosis of clinically relevant allergen-specific asthma. The following parameters were measured to explore predictors for an early and late asthmatic response (EAR and LAR): standardised questionnaire, skin prick test (SPT), total IgE, specific IgE to grass pollen, FEV1, PD20FEV1 methacholine, exhaled nitric oxide (eNO) and eosinophils.

RESULTS

Early asthmatic reaction was equally distributed between patients with and without signs of possible asthma by questionnaire (56.8% vs. 48.3%). The following cut-off values showed the best combination of sensitivity and specificity for an EAR: specific IgE grass pollen 18.5 kU/L (AUC 0.83), SPT 8.5 mm (AUC 0.76), total IgE 95.5 kU/L (AUC 0.73), FEV1 102.4% (AUC 0.69), PD20FEV1 methacholine 1.67 mg (AUC 0.74), eNO 18.05 ppB (AUC 0.64) and eosinophils 115/mm(3) (AUC 0.58).

CONCLUSIONS AND CLINICAL RELEVANCE

There is a considerable discordance between reported asthma signs and diagnosed disease by BAP. Simple measurement of allergen-specific IgE for grass pollen was the best predictor of allergen-induced asthma in patients with AR.