Medizin
Refine
Year of publication
- 2019 (126) (remove)
Has Fulltext
- yes (126)
Is part of the Bibliography
- no (126)
Keywords
- inflammation (9)
- glioblastoma (5)
- macrophage (4)
- Gene expression (3)
- differentiation (3)
- hypoxia (3)
- immunotherapy (3)
- macrophage polarization (3)
- macrophages (3)
- p21 (3)
Institute
- Medizin (126)
- Sonderforschungsbereiche / Forschungskollegs (14)
- Biowissenschaften (5)
- Biochemie und Chemie (3)
- Exzellenzcluster Makromolekulare Komplexe (3)
- Frankfurt Institute for Advanced Studies (FIAS) (3)
- Psychologie (2)
- Zentrum für Arzneimittelforschung, Entwicklung und Sicherheit (ZAFES) (2)
- Biodiversität und Klima Forschungszentrum (BiK-F) (1)
- Exzellenzcluster Herz-Lungen-System (1)
Background and Aims: Vitamin D has an inhibitory role in the inflammatory signaling pathways and supports the integrity of the intestinal barrier. Due to its immunomodulatory effect, vitamin D plays a role in chronic inflammatory bowel disease (IBD) and a deficiency is associated with an increased risk for a flare. We aimed to investigate to what extent the 25-hydroxyvitamin D (25(OH)D3) level correlates with disease activity and whether a cut-off value can be defined that discriminates between active disease and remission. Methods: Patients with IBD, treated at the University Hospital Frankfurt were analyzed retrospectively. The 25(OH)D3 levels were correlated with clinical activity indices and laboratory chemical activity parameters. A deficiency was defined as 25(OH)D3 levels <30 ng/mL. Results: A total of 470 (257 female) patients with IBD were included, 272 (57.9%) with Crohn’s disease (CD), 198 (42.1%) with ulcerative colitis (UC). The median age of the patients was 41 (18–84). In 283 patients (60.2%), a vitamin D deficiency was detected. 245 (53.6%) patients received oral vitamin D supplementation, and supplemented patients had significantly higher vitamin D levels (p < 0.0001). Remission, vitamin D substitution, and male gender were independently associated with the 25(OH)D3 serum concentration in our cohort in regression analysis. A 25(OH)D3 serum concentration of 27.5 ng/mL was the optimal cut-off value. Conclusion: Vitamin D deficiency is common in IBD patients and appears to be associated with increased disease activity. In our study, vitamin D levels were inversely associated with disease activity. Thus, close monitoring should be established, and optimized supplementation should take place.
Background: Computerized virtual patients (VP) have spread into many areas of healthcare delivery and medical education. They provide various advantages like flexibility in pace and space of learning, a high degree of teaching reproducibility and a cost effectiveness. However, the educational benefit of VP as an additive or also as an alternative to traditional teaching formats remains unclear. Moreover, there are no randomized-controlled studies that investigated the use of VP in a dental curriculum. Therefore, this study investigates VP as an alternative to lecturer-led small-group teaching in a curricular, randomized and controlled setting.
Methods: Randomized and controlled cohort study. Four VP cases were created according to previously published design principles and compared with lecturer-led small group teaching (SGT) within the Oral and Maxillofacial Surgery clerkship for dental students at the Department for Cranio-, Oral and Maxillofacial Plastic Surgery, Goethe University, Frankfurt, Germany. Clinical competence was measured prior (T0), directly (T1) and 6 weeks (T2) after the intervention using theoretical tests and a self-assessment questionnaire. Furthermore, VP design was evaluated using a validated toolkit.
Results: Fifty-seven students (VP = 32; SGT = 25) agreed to participate in the study. No competence differences were found at T0 (p = 0.56). The VP group outperformed (p < .0001) the SGT group at T1. At T2 there was no difference between both groups (p = 0.55). Both interventions led to a significant growth in self-assessed competence. The VP group felt better prepared to diagnose and treat real patients and regarded VP cases as a rewarding learning experience.
Conclusions: VP cases are an effective alternative to lecture-led SGT in terms of learning efficacy in the short and long-term as well as self-assessed competence growth and student satisfaction. Furthermore, integrating VP cases within a curricular Oral and Maxillofacial Surgery Clerkship is feasible and leads to substantial growth of clinical competence in undergraduate dental students.
Introduction and Objectives: Surgical techniques such as preservation of the full functional-length of the urethral sphincter (FFLU) have a positive impact on postoperative continence rates. Thereby, data on very early continence rates after radical prostatectomy (RP) are scarce. The aim of the present study was to analyze very early continence rates in patients undergoing FFLU during RP.
Materials and Methods: Very early-continence was assessed by using the PAD-test within 24 h after removal of the transurethral catheter. The PAD-test is a validated test that measures the amount of involuntary urine loss while performing predefined physical activities within 1 h (e.g., coughing, walking, climbing stairs). Full continence was defined as a urine loss below 1 g. Mild, moderate, and severe incontinence was defined as urine loss of 1–10 g, 11–50 g, and >50 g, respectively.
Results: 90 patients were prospectively analyzed. Removal of the catheter was performed on the 6th postoperative day. Proportions for no, mild, moderate and severe incontinence were 18.9, 45.5, 20.0, and 15.6%, respectively. In logistic regression younger age was associated with significant better continence (HR 2.52, p = 0.04), while bilateral nerve-sparing (HR 2.56, p = 0.057) and organ-confined tumor (HR 2.22, p = 0.078) showed lower urine loss, although the effect was statistically not significant. In MVA, similar results were recorded.
Conclusion: Overall, 64.4% of patients were continent or suffered only from mild incontinence at 24 h after catheter removal. In general, reduced urine loss was recorded in younger patients, patients with organ-confined tumor and in patients with bilateral nerve sparing. Severe incontinence rates were remarkably low with 15.6%.
Utility of the new cobas HCV test for viral load monitoring during direct-acting antiviral therapy
(2019)
Background: The COBAS AmpliPrep/COBAS TaqMan assay HCV (CAP/CTM) is widely used in clinical routine for HCV testing. Recently, the new cobas HCV test was established for high throughput testing with minimal operator intervention. As different assays may yield different quantitative/qualitative results that possibly impact treatment decisions, the aim of this study was to externally evaluate the cobas HCV test performance in comparison to CAP/CTM in a clinically relevant setting.
Methods: Serum samples were obtained from 270 patients who received direct acting antiviral therapy with different treatment regimens at two study sites (Hannover and Frankfurt) in 2016. Overall, 1545 samples (baseline, on-treatment and follow-up) were tested in parallel by both assays.
Results: The mean difference between cobas HCV and CAP/CTM for the quantification of HCV RNA was 0.008 log10 IU/ml HCV RNA (95% limits of agreement: -0.02–0.036) showing excellent agreement of both assays. With respect to clinical cut offs (HCV RNA detectable vs. target not detected and HCV RNA above the lower limit of quantification (LLOQ) vs. <LLOQ), discordant results were obtained in 9.5% and 4.6%, respectively; the greatest differences were observed during early stages of antiviral therapy (week 1, week 2 and week 4), but none were statistically significant. Overall percent agreement for SVR between cobas HCV and CAP/CTM at the 15 IU/ml cutoff was 99.2% (95%CI 92.7%-100%).
Conclusion: The performance of the new cobas HCV test was comparable to CAP/CTM in a clinical setting representing a large patient population with HCV GT 1 and 3 treated with DAAs.
uORF-tools—workflow for the determination of translation-regulatory upstream open reading frames
(2019)
Ribosome profiling (ribo-seq) provides a means to analyze active translation by determining ribosome occupancy in a transcriptome-wide manner. The vast majority of ribosome protected fragments (RPFs) resides within the protein-coding sequence of mRNAs. However, commonly reads are also found within the transcript leader sequence (TLS) (aka 5’ untranslated region) preceding the main open reading frame (ORF), indicating the translation of regulatory upstream ORFs (uORFs). Here, we present a workflow for the identification of translation-regulatory uORFs. Specifically, uORF-Tools uses Ribo-TISH to identify uORFs within a given dataset and generates a uORF annotation file. In addition, a comprehensive human uORF annotation file, based on 35 ribo-seq files, is provided, which can serve as an alternative input file for the workflow. To assess the translation-regulatory activity of the uORFs, stimulus-induced changes in the ratio of the RPFs residing in the main ORFs relative to those found in the associated uORFs are determined. The resulting output file allows for the easy identification of candidate uORFs, which have translation-inhibitory effects on their associated main ORFs. uORF-Tools is available as a free and open Snakemake workflow at https://github.com/Biochemistry1-FFM/uORF-Tools. It is easily installed and all necessary tools are provided in a version-controlled manner, which also ensures lasting usability. uORF-Tools is designed for intuitive use and requires only limited computing times and resources.
Objectives: The present randomized clinical trial assesses the six-month outcomes following surgical regenerative therapy of periimplantitis lesions using either an electrolytic method (EC) to remove biofilms or a combination of powder spray and electrolytic method (PEC).
Materials and Methods: 24 patients with 24 implants suffering from peri-implantitis with any type of bone defect were randomly treated by EC or PEC. Bone defects were augmented with a mixture of natural bone mineral and autogenous bone and left for submerged healing. The distance from implant shoulder to bone was assessed at six defined points at baseline (T0) and after six months at uncovering surgery (T1) by periodontal probe and standardized x-rays.
Results: One implant had to be removed at T1 because of reinfection and other obstacles. None of the other implants showed signs of inflammation. Bone gain was 2.71 ± 1.70 mm for EC and 2.81 ± 2.15 mm for PEC. No statistically significant difference between EC and PEC was detected. Significant clinical bone fill was observed for all 24 implants. Complete regeneration of bone was achieved in 12 implants. Defect morphology impacted the amount of regeneration.
Conclusion: EC needs no further mechanical cleaning by powder spray. Complete re-osseointegration in peri-implantitis cases is possible.
Background: GLUT1-deficiency-syndrome (G1DS) is an autosomal dominant genetic disorder based on a mutation of the SLC2A1 gene. This mutation can lead to an encephalopathy due to abnormal glucose transport in the brain. G1DS is a rare disease, with an estimated incidence of 1: 90 000.
Case report: We report a case of a 10-year-old female who presented with recurrent fever, headaches, and vertigo for more than 3 days within 2 weeks following pneumonia. A bilateral mastoiditis was proven by a cerebral magnetic resonance imaging and a cranial computed tomography scan. The patient had to undergo mastoidectomy and thus, her first general anesthesia. Half a year previously she was diagnosed with G1DS. According to the standard of care, a ketogenic diet had been administered since the patient’s diagnosis 6 months earlier. Our patient received a total intravenous anesthesia (TIVA) using propofol, fentanyl, and rocuronium administered without any incidents.
Conclusions: We recommend normoglycemia during the perioperative phase and avoidance of glucose-based medication to keep a patient’s ketotic state. Our case highlights that TIVA, with the outlined medication used in this case, was safe when the patient’s ketotic state and periprocedural blood glucose was monitored continuously. Nevertheless, we would suggest using remifentanil instead of fentanyl for future TIVAs due to a reduced increase in blood glucose level in our patient.
IL-1 family member IL-33 exerts a variety of immune activating and regulating properties and has recently been proposed as a prognostic biomarker for cancer diseases, although its precise role in tumor immunity is unclear. Here we analyzed in vitro conditions influencing the function of IL-33 as an alarmin and a co-factor for the activity of cytotoxic CD8+ T cells in order to explain the widely discussed promiscuous behavior of IL-33 in vivo. Circulating IL-33 detected in the serum of healthy human volunteers was biologically inactive. Additionally, bioactivity of exogenous recombinant IL-33 was significantly reduced in plasma, suggesting local effects of IL-33, and inactivation in blood. Limited availability of nutrients in tissue causes necrosis and thus favors release of IL-33, which—as described before—leads to a locally high expression of the cytokine. The harsh conditions however influence T cell fitness and their responsiveness to stimuli. Nutrient deprivation and pharmacological inhibition of mTOR mediated a distinctive phenotype characterized by expression of IL-33 receptor ST2L on isolated CD8+ T cells, downregulation of CD8, a transitional CD45RAlowROlow phenotype and high expression of secondary lymphoid organ chemokine receptor CCR7. Under nutrient deprivation, IL-33 inhibited an IL-12 induced increase in granzyme B protein expression and increased expression of GATA3 and FOXP3 mRNA. IL-33 enhanced the TCR-dependent activation of CD8+ T cells and co-stimulated the IL-12/TCR-dependent expression of IFNγ. Respectively, GATA3 and FOXP3 mRNA were not regulated during TCR-dependent activation. TCR-dependent stimulation of PBMC, but not LPS, initiated mRNA expression of soluble IL-33 decoy receptor sST2, a control mechanism limiting IL-33 bioactivity to avoid uncontrolled inflammation. Our findings contribute to the understanding of the compartment-specific activity of IL-33. Furthermore, we newly describe conditions, which promote an IL-33-dependent induction of pro- or anti-inflammatory activity in CD8+ T cells during nutrient deprivation.
Glioblastoma (GBM), WHO grade IV, is the most aggressive primary brain tumor in adults. The median survival time using standard therapy is only 12–15 months with a 5-year survival rate of around 5%. Thus, new and effective treatment modalities are of significant importance. Signal transducer and activator of transcription 3 (Stat3) is a key signaling protein driving major hallmarks of cancer and represents a promising target for the development of targeted glioblastoma therapies. Here we present data showing that the therapeutic application of siRNAs, formulated in nanoscale lipopolyplexes (LPP) based on polyethylenimine (PEI) and the phospholipid 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC), represents a promising new approach to target Stat3 in glioma. We demonstrate that the LPP-mediated delivery of siRNA mediates efficient knockdown of Stat3, suppresses Stat3 activity and limits cell growth in murine (Tu2449) and human (U87, Mz18) glioma cells in vitro. In a therapeutic setting, intracranial application of the siRNA-containing LPP leads to knockdown of STAT3 target gene expression, decreased tumor growth and significantly prolonged survival in Tu2449 glioma-bearing mice compared to negative control-treated animals. This is a proof-of-concept study introducing PEI-based lipopolyplexes as an efficient strategy for therapeutically targeting oncoproteins with otherwise limited druggability.
The thrombopoietin receptor agonist eltrombopag was successfully used against human cytomegalovirus (HCMV)-associated thrombocytopenia refractory to immunomodulatory and antiviral drugs. These effects were ascribed to the effects of eltrombopag on megakaryocytes. Here, we tested whether eltrombopag may also exert direct antiviral effects. Therapeutic eltrombopag concentrations inhibited HCMV replication in human fibroblasts and adult mesenchymal stem cells infected with six different virus strains and drug-resistant clinical isolates. Eltrombopag also synergistically increased the anti-HCMV activity of the mainstay drug ganciclovir. Time-of-addition experiments suggested that eltrombopag interfered with HCMV replication after virus entry. Eltrombopag was effective in thrombopoietin receptor-negative cells, and the addition of Fe3+ prevented the anti-HCMV effects, indicating that it inhibits HCMV replication via iron chelation. This may be of particular interest for the treatment of cytopenias after hematopoietic stem cell transplantation, as HCMV reactivation is a major reason for transplantation failure. Since therapeutic eltrombopag concentrations are effective against drug-resistant viruses, and synergistically increase the effects of ganciclovir, eltrombopag is also a drug-repurposing candidate for the treatment of therapy-refractory HCMV diseas.
Neuroblastoma (NB) is the most common solid extracranial tumor in childhood. Despite therapeutic progress, prognosis in high-risk NB is poor and innovative therapies are urgently needed. Therefore, we addressed the potential cytotoxic capacity of interleukin (IL)-activated natural killer (NK) cells compared to cytokine-induced killer (CIK) cells for the treatment of NB. NK cells were isolated from peripheral blood mononuclear cells (PBMCs) by indirect CD56-enrichment or CD3/CD19-depletion and expanded with different cytokine combinations, such as IL-2, IL-15, and/or IL-21 under feeder-cell free conditions. CIK cells were generated from PBMCs by ex vivo stimulation with interferon-γ, IL-2, OKT-3, and IL-15. Comparative analysis of expansion rate, purity, phenotype and cytotoxicity was performed. CD56-enriched NK cells showed a median expansion rate of 4.3-fold with up to 99% NK cell content. The cell product after CD3/CD19-depletion consisted of a median 43.5% NK cells that expanded significantly faster reaching also 99% of NK cell purity. After 10–12 days of expansion, both NK cell preparations showed a significantly higher median cytotoxic capacity against NB cells relative to CIK cells. Remarkably, these NK cells were also capable of efficiently killing NB spheroidal 3D culture in long-term cytotoxicity assays. Further optimization using a novel NK cell culture medium and a prolonged culturing procedure after CD3/CD19-depletion for up to 15 days enhanced the expansion rate up to 24.4-fold by maintaining the cytotoxic potential. Addition of an IL-21 boost prior to harvesting significantly increased the cytotoxicity. The final cell product consisted for the major part of CD16−, NCR-expressing, poly-functional NK cells with regard to cytokine production, CD107a degranulation and antitumor capacity. In summary, our study revealed that NK cells have a significantly higher cytotoxic potential to combat NB than CIK cell products, especially following the synergistic use of IL-15 and IL-21 for NK cell activation. Therefore, the use of IL-15+IL-21 expanded NK cells generated from CD3/CD19-depleted apheresis products seems to be highly promising as an immunotherapy in combination with haploidentical stem cell transplantation (SCT) for high-risk NB patients.
Nonerythroid spectrin αII (SPTAN1) is an important cytoskeletal protein that ensures vital cellular properties including polarity and cell stabilization. In addition, it is involved in cell adhesion, cell-cell contact, and apoptosis. The detection of altered expression of SPTAN1 in tumors indicates that SPTAN1 might be involved in the development and progression of cancer. SPTAN1 has been described in cancer and therapy response and proposed as a potential marker protein for neoplasia, tumor aggressiveness, and therapeutic efficiency. On one hand, the existing data suggest that overexpression of SPTAN1 in tumor cells reflects neoplastic and tumor promoting activity. On the other hand, nuclear SPTAN1 can have tumor suppressing effects by enabling DNA repair through interaction with DNA repair proteins. Moreover, SPTAN1 cleavage products occur during apoptosis and could serve as markers for the efficacy of cancer therapy. Due to SPTAN1’s multifaceted functions and its role in adhesion and migration, SPTAN1 can influence tumor growth and progression in both positive and negative directions depending on its specific regulation. This review summarizes the current knowledge on SPTAN1 in cancer and depicts several mechanisms by which SPTAN1 could impact tumor development and aggressiveness.
The multifaceted p21 (Cip1/Waf1/CDKN1A) in cell differentiation, migration and cancer therapy
(2019)
Loss of cell cycle control is characteristic of tumorigenesis. The protein p21 is the founding member of cyclin-dependent kinase inhibitors and an important versatile cell cycle protein. p21 is transcriptionally controlled by p53 and p53-independent pathways. Its expression is increased in response to various intra- and extracellular stimuli to arrest the cell cycle ensuring genomic stability. Apart from its roles in cell cycle regulation including mitosis, p21 is involved in differentiation, cell migration, cytoskeletal dynamics, apoptosis, transcription, DNA repair, reprogramming of induced pluripotent stem cells, autophagy and the onset of senescence. p21 acts either as a tumor suppressor or as an oncogene depending largely on the cellular context, its subcellular localization and posttranslational modifications. In the present review, we briefly mention the general functions of p21 and summarize its roles in differentiation, migration and invasion in detail. Finally, regarding its dual role as tumor suppressor and oncogene, we highlight the potential, difficulties and risks of using p21 as a biomarker as well as a therapeutic target.
Fibrogenesis is a progressive scarring event resulting from disrupted regular wound healing due to repeated tissue injury and can end in organ failure, like in liver cirrhosis. The protagonists in this process, either liver-resident cells or patrolling leukocytes attracted to the site of tissue damage, interact with each other by soluble factors but also by direct cell-cell contact mediated by cell adhesion molecules. Since cell adhesion molecules also support binding to the extracellular matrix, they represent excellent biosensors, which allow cells to modulate their behavior based on changes in the surrounding microenvironment. In this review, we focus on selectins, cadherins, integrins and members of the immunoglobulin superfamily of adhesion molecules as well as some non-classical cell adhesion molecules in the context of hepatic fibrosis. We describe their liver-specific contributions to leukocyte recruitment, cell differentiation and survival, matrix remodeling or angiogenesis and touch on their suitability as targets in antifibrotic therapies.
The lipid status in patients with ulcerative colitis : Sphingolipids are disease-dependent regulated
(2019)
The factors that contribute to the development of ulcerative colitis (UC), are still not fully identified. Disruption of the colon barrier is one of the first events leading to invasion of bacteria and activation of the immune system. The colon barrier is strongly influenced by sphingolipids. Sphingolipids impact cell–cell contacts and function as second messengers. We collected blood and colon tissue samples from UC patients and healthy controls and investigated the sphingolipids and other lipids by LC-MS/MS or LC-QTOFMS. The expression of enzymes of the sphingolipid pathway were determined by RT-PCR and immunohistochemistry. In inflamed colon tissue, the de novo-synthesis of sphingolipids is reduced, whereas lactosylceramides are increased. Reduction of dihydroceramides was due to posttranslational inhibition rather than altered serine palmitoyl transferase or ceramide synthase expression in inflamed colon tissue. Furthermore, in human plasma from UC-patients, several sphinglipids change significantly in comparison to healthy controls. Beside sphingolipids free fatty acids, lysophosphatidylcholines and triglycerides changed significantly in the blood of colitis patients dependent on the disease severity. Our data indicate that detraction of the sphingolipid de novo synthesis in colon tissue might be an important trigger for UC. Several lipids changed significantly in the blood, which might be used as biomarkers for disease control; however, diet-related variabilities need to be considered.
Introduction: Vaginal delivery out of a breech presentation in pregnancies at term are being re-implemented into clinical practice. Still, recommendations regarding exclusion criteria leading to caesarean sections are based on expert opinions, not on evidence-based guidelines. The difference in perinatal outcome and course of delivery in births with babies in frank breech position and babies in incomplete or complete breech presentation never has been investigated in a large patient cohort.
Objective: To compare perinatal outcome of vaginally intended breech deliveries between births out of frank breech position and incomplete/complete breech presentation.
Design: Prospective cohort study.
Sample: 884 women at term with a singleton in frank breech presentation (FB) and 284 women with incomplete or complete breech presentation (CB) intending vaginal birth between January 2004 and December 2018.
Methods: Maternal and fetal outcome was compared between groups using Pearson’s Chi Square test. Birth duration parameters were analysed using logistic regression.
Results: There were no differences in cesarean section rates (FB: 25.1%, CB 22.2%, p = 0.317). Short-term fetal morbidity did not differ between groups (FB: 2.5%, CB: 2.8%, p = 0.761). In vaginal deliveries the necessity to perform manual assistance was significantly more frequent in deliveries of infants in CB (FB: 39.9%, CB: 51.6%, p = 0.0013). Cord loops (FB: 10.1%, CB: 18.0%, p = 0.0004) and cesarean sections necessary because of cord prolapses (FB: 1.4%, CB 8.1%, p = 0.005) were significantly more often in deliveries with babies in CB.
Conclusion: This study provides evidence, that perinatal morbidity is not associated with the fetal leg posture in vaginally intended breech deliveries. The higher risk for the need of manual assistance during vaginal birth in deliveries of babies out of complete or incomplete breech presentation suggests that obstetrical departments re-implementing the vaginal breech in their repertoire might start with births of babies out of frank breech presentation.
Purpose: Bacterial biofilms are a major problem in the treatment of infected dental and orthopedic implants. The purpose of this study is to investigate the cleaning effect of an electrolytic approach (EC) compared to a powder-spray system (PSS) on titanium surfaces. Materials and Methods: The tested implants (different surfaces and alloys) were collated into six groups and treated ether with EC or PSS. After a mature biofilm was established, the implants were treated, immersed in a nutritional solution, and streaked on Columbia agar. Colony-forming units (CFUs) were counted after breeding and testing (EC), and control (PSS) groups were compared using a paired sample t-test. Results: No bacterial growth was observed in the EC groups. After thinning to 1:1,000,000, 258.1 ± 19.9 (group 2), 264.4 ± 36.5 (group 4), and 245.3 ± 40.7 (group 6) CFUs could be counted in the PSS groups. The difference between the electrolytic approach (test groups 1, 3, and 5) and PSS (control groups 2, 4, and 6) was statistically extremely significant (p-value < 2.2 × 10−16). Conclusion: Only EC inactivated the bacterial biofilm, and PSS left reproducible bacteria behind. Within the limits of this in vitro test, clinical relevance could be demonstrated.
Acinetobacter baumannii is a Gram-negative pathogen that causes a multitude of nosocomial infections. The Acinetobacter trimeric autotransporter adhesin (Ata) belongs to the superfamily of trimeric autotransporter adhesins which are important virulence factors in many Gram-negative species. Phylogenetic profiling revealed that ata is present in 78% of all sequenced A. baumannii isolates but only in 2% of the closely related species A. calcoaceticus and A. pittii. Employing a markerless ata deletion mutant of A. baumannii ATCC 19606 we show that adhesion to and invasion into human endothelial and epithelial cells depend on Ata. Infection of primary human umbilical cord vein endothelial cells (HUVECs) with A. baumannii led to the secretion of interleukin (IL)-6 and IL-8 in a time- and Ata-dependent manner. Furthermore, infection of HUVECs by WT A. baumannii was associated with higher rates of apoptosis via activation of caspases-3 and caspase-7, but not necrosis, in comparison to ∆ata. Ata deletion mutants were furthermore attenuated in their ability to kill larvae of Galleria mellonella and to survive in larvae when injected at sublethal doses. This indicates that Ata is an important multifunctional virulence factor in A. baumannii that mediates adhesion and invasion, induces apoptosis and contributes to pathogenicity in vivo.
Prevalence of non-alcoholic fatty liver disease (NAFLD) is increasing. Resulting fibrosis and portal hypertension, as a possible secondary event, may necessitate treatment. Overexpression of mouse renin in the transgenic rat model, TGR(mREN2)27, leads to spontaneous development of NAFLD. Therefore, we used TGR(mREN2)27 rats as a model of NAFLD where we hypothesized increased susceptibility and investigated fibrosis and portal hypertension and associated pathways. 12-week old TGR(mREN2)27 rats received either cholestatic (BDL) or toxic injury (CCl4 inhalation). Portal and systemic hemodynamic assessments were performed using microsphere technique with and without injection of the Janus-Kinase 2 (JAK2) inhibitor AG490 or the non-peptidic Ang(1-7) agonist, AVE0991. The extent of liver fibrosis was assessed in TGR(mREN2)27 and wild-type rats using standard techniques. Protein and mRNA levels of profibrotic, renin-angiotensin system components were assessed in liver and primary hepatic stellate cells (HSC) and hepatocytes. TGR(mREN2)27 rats developed spontaneous, but mild fibrosis and portal hypertension due to the activation of the JAK2/Arhgef1/ROCK pathway. AG490 decreased migration of HSC and portal pressure in isolated liver perfusions and in vivo. Fibrosis or portal hypertension after cholestatic (BDL) or toxic injury (CCl4) was not aggravated in TGR(mREN2)27 rats, probably due to decreased mouse renin expression in hepatocytes. Interestingly, portal hypertension was even blunted in TGR(mREN2)27 rats (with or without additional injury) by AVE0991. TGR(mREN2)27 rats are a suitable model of spontaneous liver fibrosis and portal hypertension but not with increased susceptibility to liver damage. After additional injury, the animals can be used to evaluate novel therapeutic strategies targeting Mas.
Introduction: Our aim was to highlight the characteristics of pediatric Meckel's diverticulum with a special focus on its complications.
Methods: We report a group of seven patients with Meckel's diverticulum and its resection from the Department of Pediatric Surgery between 2012 and 2017. We reviewed all patient records, clinical presentation, and intraoperative findings. The diagnosis was confirmed by surgery and pathology. For a systematic literature review, we used PubMed, Medline and Google Scholar search engines to locate articles containing terms such as Meckel's diverticulum, children, pediatric, complications and symptomatic. We included article reporting on case series in English and German on pediatric patients only.
Results: All included patients (n = 7) were symptomatic. Some patients showed isolated symptoms, and others presented with a combination of symptoms that consisted of abdominal pain, bloody stool or vomiting. The median age of our seven cases was 3.5 years, including 4 male and 3 female patients. Intestinal obstruction was the most common complication; it was seen in 5 out of 7 patients (intussusception in 4 cases, volvulus in 1 case). Ectopic gastric tissue was identified in 3 cases, and inclusion of pancreatic tissue was observed in 1 case. The literature review identified 8 articles for a total of 641 patients aged between 1 day and 17 years and a male:female ratio of 2.6:1. From this group, 528 patients showed clinical symptoms related to Meckel's diverticulum. The most common symptom was abdominal pain and bloody stool. The most common surgical finding in symptomatic patients was intestinal obstruction (41%), followed by intestinal hemorrhage (34%). Complications such as perforation (10%) and diverticulitis (13%) were less frequently reported. Heterotopic tissue was confirmed on histopathology in 53% of all patients enclosing gastric, pancreatic, and both gastric and pancreatic mucosae. In one case, large intestine tissue could be found. Overall, one death was reported.
Conclusion: The presented case series and literature review found similar clinical presentations and complications of Meckel's diverticulum in children. Intestinal obstruction and bleeding are more frequent than inflammation in pediatric Meckel's diverticulum. Bowel obstruction is the leading cause for complicated Meckel's diverticulum in patients younger than 12 years.