Congenital Heart Defects in Patients with Classic Bladder Exstrophy: A Hitherto Neglected Association?

INTRODUCTION

 Classic bladder exstrophy (BE) is regarded as an isolated malformation without any further anomalies, but some studies have indicated a higher incidence of cardiac anomalies. This cross-sectional study is planned to evaluate the prevalence of congenital heart defects (CHDs) and the clinical relevance for patients with BE admitted for primary closure.

MATERIALS AND METHODS

 Patients were prospectively recruited between March 2012 and January 2019. Patients' profiles including demographic data, results of transthoracic echocardiography (TTE), as well as essential peri- and postoperative data were assessed.

RESULTS

 Thirty-nine (25 boys and 14 girls) patients with BE (median age 61 days) underwent delayed primary bladder closure. Thirty-seven (24 boys and 13 girls) patients had received TTE 1 day before surgery. CHD was detected in 7 (18.9%) out of the 39 patients, but no clinical differences between patients with and without CHD were observed peri- or postoperatively.

DISCUSSION AND CONCLUSION

 This prospective systematic evaluation shows an even higher rate of CHD in patients with BE than assumed previously. Although peri- and postoperative outcome did not differ between patients with and without CHD, we consider TTE an important additional method for ensuring a safe peri- and postoperative courses and a short- and long-term care for patients with CHD.

[Age rationing : means of resource allocation in healthcare systems]

The necessity of limiting resource in healthcare systems is becoming increasingly more evident. The population has requirements especially in the field of healthcare which are principally unlimited. However, there are only limited financial resources which can be used to satisfy the wishes of the population. For this reason rationing models are being discussed increasingly more often. One example of these models is called age rationing which means that defined services are only offered to patients up to a particular age. The aim of this article is to discuss the model of age rationing in the context of an optimized use of resources in the healthcare system.

Elevated premorbid body mass index is not associated with poor neurological outcome in the subacute state after aneurysmal subarachnoid hemorrhage

BACKGROUND

An elevated body mass index (BMI) is suggested to be a risk factor for a poor outcome after intracranial aneurysm rupture and is considered to be associated with cerebral infarction in patients with aneurysmal subarachnoid hemorrhage (SAH). The aim of this study was to analyze the association between permorbid BMI and neurological outcome.

METHODS

In this retrospective study, the patients' BMI at the time of their admission to hospital was correlated to their neurological outcome as measured by the Glasgow outcome score after two weeks and two months of treatment.

RESULTS

In contrast to other studies, there were no significant correlations between premorbid BMI and neurological outcome, shunt requirement, tracheotomy requirement and duration of stay on the intensive care unit (ICU).

CONCLUSIONS

Overweight patients have no higher risk of a poor neurological outcome after aneurysmal SAH if premorbid risk factors such as hypertension and hyperglycemia are carefully modified throughout the period of critical care.

Bench-to-bedside review: adenosine receptors--promising targets in acute lung injury?

Acute lung injury (ALI) and acute respiratory distress syndrome (ARDS) are life-threatening disorders that have substantial adverse effects on outcomes in critically ill patients. ALI/ARDS develops in response to pulmonary or extrapulmonary injury and is characterized by increased leakage from the pulmonary microvasculature and excessive infiltration of polymorphonuclear cells into the lung. Currently, no therapeutic strategies are available to control these fundamental pathophysiological processes in human ALI/ARDS. In a variety of animal models and experimental settings, the purine nucleoside adenosine has been demonstrated to regulate both endothelial barrier integrity and polymorphonuclear cell trafficking in the lung. Adenosine exerts its effects through four G-protein-coupled receptors (A1, A2A, A2B, and A3) that are expressed on leukocytes and nonhematopoietic cells, including endothelial and epithelial cells. Each type of adenosine receptor (AR) is characterized by a unique pharmacological and physiological profile. The development of selective AR agonists and antagonists, as well as the generation of gene-deficient mice, has contributed to a growing understanding of the cellular and molecular processes that are critically involved in the development of ALI/ARDS. Adenosine-dependent pathways are involved in both protective and proinflammatory effects, highlighting the need for a detailed characterization of the distinct pathways. This review summarizes current experimental observations on the role of adenosine signaling in the development of acute lung injury and illustrates that adenosine and ARs are promising targets that may be exploited in the development of innovative therapeutic strategies.

70-kDa heat shock proteins: specific interactions with HLA-DR molecules and their peptide fragments

Heat shock protein 70 (HSP70):peptide complexes are involved in MHC class I and class II-restricted antigen presentation enabling enhanced activation of antigen-specific T cells. Here, we investigated the potential of bacterial and mammalian HSP70 molecules to interact with peptide fragments from HLA-DR and the corresponding complete HLA-DR molecules. Peptide fragments were found to interact with DnaK, the HSP70 homologue from E. coli, but less with stress-inducible human Hsp70. Only a peptide sequence exclusively found in rheumatoid arthritis-protective HLA-DR molecules did not interact with DnaK. Subsequently, we investigated the interaction of complete HLA-DR molecules with HSP70 and detected a specific HSP70:HLA-DR interaction, with highest affinity for human stress-inducible Hsp70. In contrast to the peptide fragments, no allele-specific differences in Hsp70 affinity were detected with complete HLA-DR molecules. Interaction with HLA-DR molecules was increased at lowered pH values, whereas HSP70-chaperoned peptides were released at acidic pH, thus HSP70 could serve as scanner and carrier for antigenic peptides of self or foreign origin and transfer chaperoned peptides onto MHC class II molecules in acidic late endosomal compartments. Our findings indicate that direct interaction between mammalian HSP70 and HLA-DR molecules could be involved in the HSP70-mediated enhancement of MHC class II-restricted peptide presentation and CD4(+) T cell activation.

Large-scale mapping of mutations affecting zebrafish development

Background

Large-scale mutagenesis screens in the zebrafish employing the mutagen ENU have isolated several hundred mutant loci that represent putative developmental control genes. In order to realize the potential of such screens, systematic genetic mapping of the mutations is necessary. Here we report on a large-scale effort to map the mutations generated in mutagenesis screening at the Max Planck Institute for Developmental Biology by genome scanning with microsatellite markers.

Results

We have selected a set of microsatellite markers and developed methods and scoring criteria suitable for efficient, high-throughput genome scanning. We have used these methods to successfully obtain a rough map position for 319 mutant loci from the Tübingen I mutagenesis screen and subsequent screening of the mutant collection. For 277 of these the corresponding gene is not yet identified. Mapping was successful for 80 % of the tested loci. By comparing 21 mutation and gene positions of cloned mutations we have validated the correctness of our linkage group assignments and estimated the standard error of our map positions to be approximately 6 cM.

Conclusion

By obtaining rough map positions for over 300 zebrafish loci with developmental phenotypes, we have generated a dataset that will be useful not only for cloning of the affected genes, but also to suggest allelism of mutations with similar phenotypes that will be identified in future screens. Furthermore this work validates the usefulness of our methodology for rapid, systematic and inexpensive microsatellite mapping of zebrafish mutations.

The heat shock protein Hsp70 enhances antigen-specific proliferation of human CD4+ memory T cells

Heat shock proteins (HSP) can interact with a wide variety of peptides and the resulting HSP:peptide complexes are known to be highly immunogenic. The ability of HSP:peptide complexes to elicit CD8+ T cell responses by cross-presentation of exogenous antigen via MHC class I is well known. In contrast, their role in the activation of CD4+ T cells is less clearly defined, although several recent studies in mice and T cell lines suggest an involvement of HSP in the presentation of antigenic peptides via MHC class II. In this study we have investigated the potential of antigenic peptides from tetanus toxin and influenza hemagglutinin complexed to the human stress-inducible Hsp70 to enhance activation and proliferation of human memory CD4+ T cells. Hsp70:peptide complexes were found to amplify the proliferation of antigen-specific CD4+ T cells as confirmed by HLA-DR tetramer staining. Complex formation of the antigenic peptide with Hsp70 was absolutely required to elicit an antigen-specific amplification. This effect was most pronounced at low doses of antigen and decreasing APC/CD4+ T cell ratios. Taken together, we show the potential of Hsp70 to enhance antigen-specific CD4+ T cell proliferation and to increase the immunogenicity of presented peptides in human CD4+ T cells.

Determination of the peptide binding motif and high-affinity ligands for HLA-DQ4 using synthetic peptide libraries

Juvenile idiopathic arthritis (JIA) is considered to be an autoimmune disease. Various human leukocyte antigen (HLA) associations for different subgroups of this heterogeneous disease have been found. For early-onset pauciarticular arthritis (now oligoarthritic JIA), a strong association with the HLA class II haplotype DQA1*0401/DQB1*0402 (DQ4) has been described. We determined the peptide-binding specificities of this HLA-DQ molecule by screening a synthetic acetylated nonapeptide amide library with one defined and eight random sequence positions. A characteristic binding motif could be deduced. By use of these data, we designed defined specific nonapeptides and identified high-affinity ligands binding to HLA-DQ4. The peptide binding motif of HLA-DQ4 is very similar to the motif of HLA-DQ7, also associated with oligoarthritic JIA. It is, however, different from binding motifs of neutral or protective HLA-DQ molecules. Our results further support the idea of differential peptide presentation in the pathogenesis of oligoarthritic JIA.

Autoantibodies in juvenile idiopathic arthritis: glucose-6-phosphate isomerase is not a specific target

OBJECTIVE

Antibodies recognizing the ubiquitous cytosolic enzyme glucose-6-phosphate isomerase (GPI) cause arthritis in the K/BxN mouse model. Studies have shown that these antibodies are not specific for rheumatoid arthritis (RA) in humans. We evaluated GPI as a target of autoantibodies in juvenile idiopathic arthritis (JIA).

METHODS

We studied 324 serum and 48 synovial fluid (SF) samples from 103 patients with JIA, 36 with RA, and 8 with arthralgia and 11 controls. Anti-GPI antibodies were assessed by densitometrically evaluating immunoblots and ELISA using native and recombinant GPI. We determined the GPI activity of the soluble antigen in serum and SF.

RESULTS

Although several samples contained anti-GPI-IgG antibodies, this was not specific for JIA or its subgroups, or for RA. Other proteins in the GPI preparation were also frequently recognized by antibodies. Additionally, we observed increased GPI activity in patients with the systemic manifestation of JIA, but not in other patients. Neither anti-GPI concentrations nor GPI activity were associated with disease activity.

CONCLUSION

In addition to the findings in RA, our results indicate that GPI is not a general target of autoantibodies in JIA.

Retinal defects in the zebrafish bleached mutant

The recessive zebrafish mutant bleached has, apart from its defects in pigmentation, a heritable defect leading to larval blindness. Here, we analyze the retina of homozygous bleached larvae, employing morphological and electrophysiological methods. Electroretinography revealed a complete lack of electrical signals in response to light. Histological analysis of mutant retinae showed a severely affected outer retina with a hypopigmented pigment epithelium and a disorganized outer nuclear layer containing few or no intact photoreceptors. Using the TUNEL assay for cell death detection, we noticed a strong increase of apoptotic cells in all retinal cell layers, starting in young larvae even before retinal support of visual function. At later stages cell death is most pronounced at the marginal zone, where new cells are constantly added to the retina. At early stages increased apoptosis is mainly confined to the retina, while at later stages elevated cell death is al so apparent in extra-retinal tissues, particularly in the brain. Hence, the lack of visual responses in homozygous bleached larvae can be attributed to a severe defect of the outer retina, preceded by increased levels of apoptotic cell death in all retinal cell layers.