Cardiac thrombus with risk of fulminant pulmonary embolism in paediatric antiphospholipid syndrome.

Antiphospholipid Syndrome (APS) describes a systemic disease caused by autoantibodies to membrane components. Involving coagulation pathways, complement factors and immune cells, it results in thrombosis in any blood vessel. Its clinical presentation varies considerably depending upon the organ affected. Paediatric data on APS remain sparse. Most case reports focus on catastrophic APS with multiple small-vessel occlusions and a life-threatening course. Here, we report on a 15-year-old patient with deep vein thrombosis and a right ventricular tumour posing the risk of a fulminant pulmonary embolism. The tumour was surgically removed. Histology revealed it to be a thrombus. The patient fully recovered and is currently treated with long term anticoagulation.

[Prevention in the elderly: position paper on pneumococcal vaccinations. Results of an expert workshop on 15 November 2013 in Cologne, Germany]. / Prävention im Alter: Stellungnahme zur Pneumokokkenimpfung. Ergebnisse eines Expertenworkshops am 15.11.2013 in Köln.

Infections due to pneumococci especially in the elderly are vastly underestimated, e.g., because non-invasive infections such as pneumonia may appear with only few symptoms. Sequential vaccination with the pneumococcal conjugate vaccine PCV13, followed by the 23-valent polysaccharide vaccine, is considered as the best preventive measure for individual protection, even though clinical study data demonstrating the efficacy of this sequence are not yet available. Increase of "awareness" by use of computer-based reminder functions may result in a significant improvement of vaccination compliance.

Activation of EphA receptor tyrosine kinase inhibits the Ras/MAPK pathway.

Interactions between Eph receptor tyrosine kinases (RTKs) and membrane-anchored ephrin ligands critically regulate axon pathfinding and development of the cardiovascular system, as well as migration of neural cells. Similar to other RTKs, ligand-activated Eph kinases recruit multiple signalling and adaptor proteins, several of which are involved in growth regulation. However, in contrast to other RTKs, activation of Eph receptors fails to promote cell proliferation or to transform rodent fibroblasts, indicating that Eph kinases may initiate signalling pathways that are distinct from those transmitted by other RTKs. Here we show that stimulation of endogenous EphA kinases with ephrin-A1 potently inhibits the Ras/MAPK cascade in a range of cell types, and attenuates activation of mitogen-activated protein kinase (MAPK) by receptors for platelet-derived growth factor (PDGF), epidermal growth factor (EGF) and vascular endothelial growth factor (VEGF). In prostatic epithelial cells and endothelial cells, but not fibroblasts, treatment with ephrin-A1 inhibits cell proliferation. Our results identify EphA kinases as negative regulators of the Ras/MAPK pathway that exert anti-mitogenic functions in a cell-type-specific manner.

Medical students' knowledge and attitudes regarding vaccination against measles, influenza and HPV. An international multicenter study.

INTRODUCTION: Inaccurate information leads to increased scepticism concerning vaccinations among health care workers. Therefore, a proper education of medical students on vaccination is important. METHODS: During summer term 2015, we performed a paper-based survey to identify the knowledge and attitudes of medical students on vaccinations against measles, influenza and HPV in seven medical schools in Germany, Austria and Switzerland. RESULTS: Altogether, 3,652 questionnaires were analyzed. Knowledge of country-specific public recommendations increased significantly with the number of semesters of medical studies. Concerning the knowledge about vaccinations against measles, influenza and HPV, one third of the answers were given correctly. Again, a strong correlation between the knowledge and the semester of medical studies could be observed. The attitudes concerning vaccinations in general and especially for HCWs were highly positive. CONCLUSIONS: This study provides some important arguments for the development of a comprehensive vaccination education for medical students.

Cytoskeleton-dependent endocytosis is required for apical type 1 angiotensin II receptor-mediated phospholipase C activation in cultured rat proximal tubule cells.

Renal proximal tubule sodium reabsorption is enhanced by apical or basolateral angiotensin II (AII). Although AII activates phospholipase C (PLC) in other tissues, AII coupling to PLC on either apical or basolateral surfaces of proximal tubule cells is unclear. To determine if AII causes PLC activation, and the differences between apical and basolateral AII receptor function, receptors were unilaterally activated in rat proximal tubule cells cultured on permeable, collagen-coated supports. Apical AII incubation resulted in concentration- and time-dependent inositol trisphosphate (IP3) formation. Basolateral AII caused greater IP3 responses. Apical AII-induced IP3 generation was inhibited by DuP 753, suggesting that the type 1 AII receptor subtype mediated proximal tubule PLC activation. Apical AII signaling did not result from paracellular ligand leak to basolateral receptors since AII-induced PLC activation occurred when basolateral AII receptors were occupied by Sar-Leu AII or DuP 753. Inhibition of endocytosis with phenylarsine oxide prevented apical (but not basolateral) AII-induced IP3 formation. Cytoskeletal disruption with colchicine or cytochalasin D also prevented apical AII-induced IP3 generation. These results demonstrate that in cultured rat proximal tubule cells, AII is coupled to PLC via type 1 AII receptors and cytoskeleton-dependent endocytosis is required for apical (but not basolateral) AII receptor-mediated PLC activation.

The IL-1 receptor and Rho directly associate to drive cell activation in inflammation.

IL-1-stimulated mesenchymal cells model molecular mechanisms of inflammation. Binding of IL-1 to the type I IL-1 receptor (IL-1R) clusters a multi-subunit signaling complex at focal adhesion complexes. Since Rho family GTPases coordinately organize actin cytoskeleton and signaling to regulate cell phenotype, we hypothesized that the IL-1R signaling complex contained these G proteins. IL-1 stimulated actin stress fiber formation in serum-starved HeLa cells in a Rho-dependent manner and rapidly activated nucleotide exchange on RhoA. Glutathione S-transferase (GST) fusion proteins, containing either the full-length IL-1R cytosolic domain (GST-IL-1Rcd) or the terminal 68 amino acids of IL-1R required for IL-1-dependent signal transduction, specifically coprecipitated both RhoA and Rac-1, but not p21(ras), from Triton-soluble HeLa cell extracts. In whole cells, a small-molecular-weight G protein coimmunoprecipitated by anti-IL-1R antibody was a substrate for C3 transferase, which specifically ADP-ribosylates Rho GTPases. Constitutively activated RhoA, loaded with [gamma-32P]GTP, directly interacted with GST-IL-1Rcd in a filter-binding assay. The IL-1Rcd-RhoA interaction was functionally important, since a dominant inhibitory mutant of RhoA prevented IL-1Rcd-directed transcriptional activation of the IL-6 gene. Consistent with our previous data demonstrating that IL-1R-associated myelin basic protein (MBP) kinases are necessary for IL-1-directed gene expression, cellular incorporation of C3 transferase inhibited IL-1R-associated MBP kinase activity both in solution and in gel kinase assays. In summary, IL-1 activated RhoA, which was physically associated with IL-1Rcd and necessary for activation of cytosolic nuclear signaling pathways. These findings suggest that IL-1-stimulated, Rho-dependent cytoskeletal reorganization may cluster signaling molecules in specific architectures that are necessary for persistent cell activation in chronic inflammatory disease.

The NHE1 Na+/H+ exchanger regulates cell survival by activating and targeting ezrin to specific plasma membrane domains.

NHE1 is a ubiquitously expressed Na+/H+ exchanger, which is important for vital cell functions. Using in vivo models of kidney podocyte injury and renal tubular epithelial cell (RTC) culture systems, we previously demonstrated that NHE1 defends against apoptosis by a mechanism involving ezrin binding to the NHE1 cytoplasmic domain. We now extend the NHE1 role to diabetic mouse models and refine the mechanism of NHE1-dependent ezrin activation. Streptozotocin induced diabetes resulted in greater azotemia, albuminuria and tubulointerstitial pathology in NHE1-deficient swe/swe compared to wild-type control mice. Increased RTC apoptosis was noted in swe/swe mice, suggesting that loss of NHE1 function leads to tubular atrophy, which predicts kidney disease progression. In vitro, proximal RTC derived from swe/swe mice also underwent increased apoptosis in response to staurosporine or a hypertonic environment. Activated ezrin normally resides in the apical domain of the proximal RTC, while NHE1 is a basolateral protein. After NHE1 activation by intracellular acidification or extracellular hypertonicity, confocal immunofluorescence microscopy in polarized LLC-PK1 cells demonstrated transient ezrin localization to lateral membrane domains, where it is positioned to interact with NHE1. We conclude that cell stresses promote NHE1-ezrin interaction, which activate cell survival pathways to prevent apoptosis in diabetic and non-diabetic kidney diseases.

Vaccination: Developing and implementing a competency-based-curriculum at the Medical Faculty of LMU Munich.

BACKGROUND: In Germany medical students should gain proficiency and specific skills in the vaccination field. Especially important is the efficient communication of scientific results about vaccinations to the community, in order to give professional counseling with a complete overview about therapeutic options. AIM OF THE PROJECT: The aim of this project is to set up a vaccination-related curriculum in the Medical Faculty at the Ludwig-Maximilians-University in Munich. The structure of the curriculum is based on the National catalogue for competency-based learning objectives in the field of vaccination (Nationaler Kompetenzbasierter Lernzielekatalog Medizin NKLM). Through this curriculum, the students will not only acquire the classical educational skills concerning vaccination in theory and practice, but they will also learn how to become independent in the decision-making process and counseling. Moreover, the students will become aware of consequences of action related to this specific topic. METHODS: According to defined guidelines, an analysis was performed on courses, which are currently offered by the university. A separate analysis of the NKLM was carried out. Both analyses identified the active courses related to the topic of vaccination as well as the NKLM learning objectives. The match between the topics taught in current courses and the NKLM learning objectives identified gaps concerning the teaching of specific content. Courses were modified in order to implement the missing NKLM learning objectives. RESULTS: These analyses identified 24 vaccination-related courses, which are currently taught at the University. Meanwhile, 35 learning objectives on vaccination were identified in the NKLM catalogue. Four of which were identified as not yet part of the teaching program. In summary, this interdisciplinary work enabled the development of a new vaccination-related curriculum, including 35 learning objectives, which are now implemented in regular teaching courses by the Medical Faculty. CONCLUSIONS: This project successfully describes a method to develop and implement a competency-based teaching program on the topic of vaccination. Importantly, the process presented here can serve as a guide to develop and implement similar teaching programs on other subjects and Universities.

Aldosterone enhances angiotensin II receptor binding and inositol phosphate responses.

Clinical states in which angiotensin II is increased are often associated with increases in mineralocorticoids. To determine the effects of mineralocorticoids on angiotensin II action, we examined the effects of aldosterone on angiotensin II receptor expression and function in cultured rat vascular smooth muscle cells. Incubation with aldosterone resulted in concentration- and time-dependent increases in angiotensin II receptor number, without changes in binding affinity. For example, incubation with 1 microM aldosterone for 40 hours resulted in 59% increases in angiotensin II receptor number. Increases in angiotensin II receptors were dependent on protein synthesis as evidenced by the time dependency of upregulation and inhibition by cycloheximide. Incubation with aldosterone resulted in enhanced angiotensin II-stimulated phospholipase C activation, as demonstrated by increases in angiotensin II-induced inositol phosphate responses in proportion to the increases in receptor number. In addition, aldosterone prevented angiotensin II-induced downregulation of angiotensin II surface receptors and angiotensin II desensitization of inositol phosphate formation. In summary, aldosterone 1) directly increased angiotensin II receptor number, 2) increased angiotensin II-stimulated inositol phosphate responses, and 3) prevented angiotensin II-induced downregulation and desensitization. In conclusion, aldosterone may potentiate the pressor responses of angiotensin II via effects on angiotensin II receptors.

Effect of foodstuffs on the absorption of zinc sulfate.

Single doses of zinc sulfate were given to healthy young volunteers, either in the fasting state or with various types of meals. Dairy products (milk and cheese) and brown bread decreased zinc absorption, as indicated by a significant drop in peak serum zinc levels. Zinc absorption was decreased when zinc was given in the fasting state with the same amounts of purified phosphate or phytate as those found in foods above. Experiments in vitro have shown that zinc is precipitated by phosphate and phytate at pH values close to that of the intestinal lumen. Coffee also seems to inhibit zinc absorption.

Judgments of trained observers on adverse drug reactions.

Patients (672) admitted to a department of medicine during five consecutive months were followed by an investigator who identified 110 clinical manifestations which could have been considered adverse drug reactions. From these, 42 were excluded because they did not correspond to the definition of adverse reaction or they were inadequately documented. The remaining 68 cases were submitted to three independent observers who had to reply to a series of questions; from these replies five degrees of probability for the reaction itself were deduced. Reactions (54; 49% of the manifestations reported) were considered as certain or probable by at least two observers, but only 27 rections of these (25%) were attributed to the same drug by all three observers. There was a low level of agreement between any two observers (paired agreement ratio: 0.6 to 0.7) and little difference of agreement between any one observer and each of the others (personal agreement ratio: 0.6 to 0.7).

Absence of metabolic effects of the topical carbonic anhydrase inhibitors MK-927 and sezolamide during two-week ocular administration to normal subjects.

Potential systemic effects of the racemic carbonic anhydrase inhibitor MK-927 and its S-enantiomer, sezolamide hydrochloride, after topical ocular administration were investigated in a double-masked, randomized, placebo-controlled study in 16 healthy volunteers. A controlled diet was started 4 days before initiation of treatment and continued throughout the study. For 14 days six volunteers received bilaterally one drop of 2% MK-927 (1.2 mg) q.i.d., six received one drop of 1.8% sezolamide (1.1 mg) q.i.d., and four received the common vehicle q.i.d. Blood and urine electrolytes and acid-base profiles were measured before and on days 1, 7, and 14 of treatment, and 24-hour urine samples were collected daily. All values were compared with those on the pretreatment day. Taking the circadian variations of the parameters into account, no significant treatment effect was observed in either the daily profiles or the 14-day cumulative sodium, potassium, and citrate excretions. Because the usual variability of the measured biologic parameters has been reduced markedly by the stringent requirements of this study, it can be concluded that the induction of clinically significant metabolic changes by topically administered MK-927 or sezolamide is unlikely.

Influence of food and antacid administration on fluoride bioavailability from enteric-coated sodium fluoride tablets.

The relative bioavailability of enteric-coated sodium fluoride (NaF) tablets (10 mg F-) has been assessed following administration with a standard calcium-rich breakfast or calcium-poor lunch, and 2 h before or simultaneously with antacid administration (2.4 g aluminum-magnesium hydroxide), versus intake on an empty stomach. Twelve volunteers were studied 3 times according to an open, three-way crossover design over a 24 h period at weekly intervals. Meals were found to decrease the peak serum concentration of NaF from 122 micrograms/L during fasting (after baseline subtraction) to 71 and 88 micrograms/L with breakfast and lunch respectively, and to slow its absorption rate with Tmax increasing from 3.3 to 7.3 and 11.2 hours, without altering its bioavailability. Antacid impaired the bioavailability of NaF by 80% when administered simultaneously, with AUC decreasing from 987 to 155 micrograms.h/L, but had no significant effect when taken 2 h before NaF. In conclusion, the enteric-coated NaF tablets used in this study can be administered with food or after a 2-hour delay following antacid administration, but should not be taken simultaneously with antacid.

A family-based strategy to identify genes for diabetic nephropathy.

Diabetic nephropathy (DN) clusters in families and specific ethnic groups, suggesting a genetic basis of disease transmission. Identification of DN susceptibility loci should reveal new therapeutic targets but requires accurate phenotyping. A powerful family-based strategy, which is novel to the pursuit of nephropathy genes in type 2 diabetes, is being used to collect a sample for candidate gene and genome scan analyses. Sib pairs that include DN index cases plus (1) sibs concordant for type 2 diabetes and DN (affected sib pairs [ASPs]) and (2) sibs concordant for type 2 diabetes but discordant for DN (discordant sib pairs [DSPs]) are targeted specifically for recruitment. Type 2 diabetes and DN phenotype criteria for index cases include diabetes onset after 38 years of age, duration 10 years or longer, no initial insulin treatment, diabetic retinopathy, end-stage renal disease (ESRD), and history of nephrotic proteinuria. ESRD patients were screened by questionnaire and medical record review (n = 2114). Of 666 patients with ESRD secondary to DN, 227 had a family history of ESRD, 150 had a living diabetic sib, and 124 families were enrolled. Sixty-five families, with 86 diabetic relative pairs (69 sibs, 17 children), have been completely phenotyped. If nephropathy in diabetic sibs is defined as albuminuria greater than 0.3 g/24 h, 31 ASPs and 26 DSPs (diabetic sib with albuminuria <0.3 g/24 h) were identified. Applying more stringent criteria, only 12 ASPs (sib with diabetes >10 years, diabetic retinopathy, and nephrotic proteinuria) and 9 DSPs (sib with diabetes >10 years and normal urine albumin excretion) were identified. Extrapolating from the number of subjects recruited using stringent phenotyping criteria, nearly 10,000 ESRD patients are required for screening to achieve adequate statistical power for linkage analysis (80% power to detect locus-specific relative risk of 2.2 at a lod score of 3.0). Careful phenotyping requires a large recruitment effort but is necessary to reduce population heterogeneity, a strategy that increases the likelihood of identifying DN loci.

Fatal hypermagnesemia.

Severe symptomatic hypermagnesemia is a rare clinical problem that predominantly results from excess exogenous magnesium intake in patients with renal failure. This report describes an elderly woman who was given a magnesium-containing cathartic for pre-operative bowel preparation in the context of unrecognized acute renal failure. She subsequently developed one of the highest serum magnesium concentrations ever reported. The hypermagnesemia was successfully treated with continuous arteriovenous hemodialysis, but she ultimately died from complications of hypermagnesemia, that included junctional bradycardia, myocardial infarction and respiratory failure. This case illustrates the importance of ensuring intact renal function prior to administering large quantities of oral magnesium. More specifically, large doses of magnesium salts should be avoided in patients with acute renal failure.

Gelfoam for closure of large percutaneous transhepatic and transsplenic puncture tracts in pediatric patients.

PURPOSE: Evaluation of the efficacy and safety of Gelfoam for the closure of transhepatic or transsplenic parenchymal puncture tracts with large-bore sheaths in pediatric patients. MATERIALS AND METHODS: Between January 2012 and May 2013, 8 percutaneous transhepatic accesses and 3 percutaneous transsplenic accesses were closed using percutaneous Gelfoam in pediatric patients. The primary study endpoints to determine treatment efficacy and safety were patient survival, technical success defined as successful closure of the puncture tract without signs of bleeding, and complication rates. The secondary study endpoints were the occurrence of local and systemic inflammation. RESULTS: Overall survival was 100 % with a median follow-up of 256 days. The procedure was technically successful in 10 of 11 procedures. One patient suffered from bleeding, which was successfully managed by a single blood transfusion. No re-bleeding was detected during follow-up and no surgical interventions were necessary. No signs of local or systemic infections related to the Gelfoam application occurred. CONCLUSION: Percutaneous Gelfoam application is an effective and safe technique for the closure of transhepatic or transsplenic accesses in pediatric patients. KEY POINTS: Interventional closure of large transhepatic and transsplenic parenchymal accesses in children after interventional treatment is recommended to avoid bleeding. Gelfoam application does not cause artifacts in magnetic resonance imaging and does not increase the risk of local or systemic inflammation in comparison to permanent embolic agents. Thus, especially children under immunosuppressive therapy can benefit from the application of Gelfoam.