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Dive into the research topics where Steffen Michael Berger is active.

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Featured researches published by Steffen Michael Berger.


Pediatric Research | 2008

Higher Cord Blood Levels of Mannose-Binding Lectin-Associated Serine Protease-2 in Infants With Necrotising Enterocolitis

Luregn J. Schlapbach; Christoph Aebi; Urs Fisch; Roland A. Ammann; Margrith Otth; Susanne Bigler; Mathias Nelle; Steffen Michael Berger; Ulf Kessler

Necrotising enterocolitis (NEC) causes significant morbidity and mortality in premature infants. The role of innate immunity in the pathogenesis of NEC remains unclear. Mannose-binding lectin (MBL) recognizes microorganisms and activates the complement system via MBL-associated serine protease-2 (MASP-2). The aim of this study was to investigate whether MBL and MASP-2 are associated with NEC. This observational case-control study included 32 infants with radiologically confirmed NEC and 64 controls. MBL and MASP-2 were measured in cord blood using ELISA. Multivariate logistic regression was performed. Of the 32 NEC cases (median gestational age, 30.5 wk), 13 (41%) were operated and 5 (16%) died. MASP-2 cord blood concentration ranged from undetectable (<10 ng/mL) to 277 ng/mL. Eighteen of 32 (56%) NEC cases had higher MASP-2 levels (≥30 ng/mL) compared with 22 of 64 (34%) controls (univariate OR 2.46; 95% CI 1.03–5.85; p = 0.043). Higher cord blood MASP-2 levels were significantly associated with an increased risk of NEC in multivariate analysis (OR 3.00; 95% CI 1.17–7.93; p = 0.027). MBL levels were not associated with NEC (p = 0.64). In conclusion, infants later developing NEC had significantly higher MASP-2 cord blood levels compared with controls. Higher MASP-2 may favor complement-mediated inflammation and could thereby predispose to NEC.


Thrombosis Research | 2011

Comparison of porcine and human coagulation by thrombelastometry

Ulf Kessler; Tamar Grau; Fabrizio Gronchi; Steffen Michael Berger; Sebastian Brandt; Hendrik Bracht; Carlo Marcucci; Zacharias Zachariou; Stephan M. Jakob

INTRODUCTION Although the pig is a standard model for the evaluation of various diseases in humans, including coagulopathy, it is not clear whether results in animals can be extrapolated to man. MATERIALS AND METHODS In 75 anesthetized pigs, we assessed reagent-supported thrombelastometry (ExTEM®), platelet-blocked thrombelastometry (FibTEM®), and aprotinin thrombelastometry (ApTEM®). Results were compared to values from 13 anesthetized humans. RESULTS (MEDIAN, 95% CI): ExTEM®: While clot strength was comparable in pigs (66 mm, 65-67 mm) and in humans (64 mm, 60-68 mm; NS), clotting time in animals was longer (pigs 64 s, 62-66 s; humans 55 s, 49-71 s; P<0.05) and clot formation time shorter (pigs 52 s, 49-54 s; humans 83 s, 67-98 s, P<0.001). The clot lysis index at 30 minutes was lower in animals (96.9%, 95.1-97.3%) than in humans (99.5%, 98.6-99.9%; P<0.001). ApTEM® showed no hyperfibrinolysis in animals. Modification of the anesthesia protocol in animals resulted in significant ExTEM® changes. FibTEM®: Complete platelet inhibition yielded significantly higher platelet contribution to clot strength in pigs (79%, 76-81%) than in humans (73%, 71-77%; P<0.05), whereas fibrinogen contribution to clot strength was higher in humans (27%, 24-29%) than in animals (21%, 19-24%; P<0.05). CONCLUSIONS Maximum clot firmness is comparable in human and porcine blood. However, clot lysis, platelet and fibrinogen contribution to clot strength, as well as initiation and propagation of clotting, are considerably different between pigs and humans. In addition, anesthesic drugs seem to influence thrombelastometry in animals. Accordingly, coagulation abnormalities in pigs subjected to diseases may not necessarily represent the coagulation profile in sick patients.


EBioMedicine | 2017

The Tim-3-galectin-9 Secretory Pathway is Involved in the Immune Escape of Human Acute Myeloid Leukemia Cells

Isabel Gonçalves Silva; Inna M. Yasinska; Svetlana S. Sakhnevych; Walter Fiedler; Jasmin Wellbrock; Marco Bardelli; Luca Varani; Rohanah Hussain; Giuliano Siligardi; Giacomo Ceccone; Steffen Michael Berger; Yuri A. Ushkaryov; Bernhard F. Gibbs; Elizaveta Fasler-Kan; Vadim V. Sumbayev

Acute myeloid leukemia (AML) is a severe and often fatal systemic malignancy. Malignant cells are capable of escaping host immune surveillance by inactivating cytotoxic lymphoid cells. In this work we discovered a fundamental molecular pathway, which includes ligand-dependent activation of ectopically expressed latrophilin 1 and possibly other G-protein coupled receptors leading to increased translation and exocytosis of the immune receptor Tim-3 and its ligand galectin-9. This occurs in a protein kinase C and mTOR (mammalian target of rapamycin)-dependent manner. Tim-3 participates in galectin-9 secretion and is also released in a free soluble form. Galectin-9 impairs the anti-cancer activity of cytotoxic lymphoid cells including natural killer (NK) cells. Soluble Tim-3 prevents secretion of interleukin-2 (IL-2) required for the activation of cytotoxic lymphoid cells. These results were validated in ex vivo experiments using primary samples from AML patients. This pathway provides reliable targets for both highly specific diagnosis and immune therapy of AML.


European Journal of Trauma and Emergency Surgery | 2011

Clinical evaluation of end caps in elastic stable intramedullary nailing of femoral and tibial shaft fractures in children

Theddy Slongo; Laurent Audigé; James B. Hunter; Steffen Michael Berger

BackgroundElastic stable intramedullary nailing (ESIN) may be complicated by the loss of reduction following push out of the nails at the entry site in unstable femoral and tibial fractures, especially in older and heavier children and following technical failures. An end cap system addressing this complication was evaluated clinically.MethodsIn a retrospective case series, 49 femoral and five tibial fractures in 54 pediatric patients treated by ESIN and end caps were documented in two European tertiary centers. End caps were used to interlock standard ESIN nails. The results were evaluated regarding difficulties in the placement and removal of the end cap system, fracture stability and healing, and return to normal activities by analyzing patient charts and X-rays.ResultsFifty-three of 54 fractures were stabilized sufficiently with ESIN and end caps. Loss of reduction was observed in one patient, requiring additional surgery. Six complications were observed, five of which were not related to end caps. There were no significant leg length differences or varus/valgus deformities. A rotational difference of >10°–20° was found in one patient. Removal of the end caps and nails was rated as simple and uncomplicated in 35/37 cases.ConclusionsEnd caps avoided postoperative instability in the majority of pediatric patients with lower limb shaft fractures, even in heavier, older patients and those with instable fracture types. End caps, however, will not compensate for operative technical insufficiency concerning reduction or nail placement. To maximize the stability of ESIN-instrumented unstable fractures, end caps require properly placed nails.


Pediatric Blood & Cancer | 2009

Treatment of intestinal and hepatic mucormycosis in an immunocompromized child

Sonja Lüer; Steffen Michael Berger; Miriam Diepold; Andrea Duppenthaler; Michael von Gunten; Konrad Mühlethaler; Rainer Wolf; Christoph Aebi

During ALL chemotherapy, a 4‐year‐old patient presented with febrile neutropenia and abdominal pain. Ultrasound examinations were repeatedly normal. Computerized tomography on day 7 demonstrated appendicitis and multiple hepatic foci identified as mucormycosis (Absidia corymbifera). Successful outcome was achieved by aggressive re‐surgery, long‐term antifungal therapy with serum level‐monitored posaconazole, and recovery of neutrophil counts. Considering the interference of posaconazole with CYP3A4, vincristine was administered during 72 hr posaconazole windows. Pediatric intestinal mucormycosis, still associated with a >70% case‐fatality rate, calls for early imaging and surgery to establish the diagnosis, reduce the fungal mass, and provide a rationale for using posaconazole. Pediatr Blood Cancer 2009;52:872–874.


OncoImmunology | 2016

The immune receptor Tim-3 acts as a trafficker in a Tim-3/galectin-9 autocrine loop in human myeloid leukemia cells

Isabel Gonçalves Silva; Laura Rüegg; Bernhard F. Gibbs; Marco Bardelli; Alexander Fruehwirth; Luca Varani; Steffen Michael Berger; Elizaveta Fasler-Kan; Vadim V. Sumbayev

ABSTRACT The immune receptor Tim-3 is often highly expressed in human acute myeloid leukemia (AML) cells where it acts as a growth factor and inflammatory receptor. Recently, it has been demonstrated that Tim-3 forms an autocrine loop with its natural ligand galectin-9 in human AML cells. However, the pathophysiological functions of Tim-3 in human AML cells remain unclear. Here, we report for the first time that Tim-3 is required for galectin-9 secretion in human AML cells. However, this effect is cell-type specific and was found so far to be applicable only to myeloid (and not, for example, lymphoid) leukemia cells. We concluded that AML cells might use Tim-3 as a trafficker for the secretion of galectin-9 which can then be possibly used to impair the anticancer activities of cytotoxic T cells and natural killer (NK) cells.


World Journal of Pediatrics | 2016

Outcome in neonates with necrotizing enterocolitis and patent ductus arteriosus.

Ulf Kessler; Franzisca Schulte; Dietmar Cholewa; Mathias Nelle; Stephan C Schaefer; Peter Michael Klimek; Steffen Michael Berger

BackgroundThere is no agreement of the influence of patent ductus arteriosus (PDA) on outcomes in patients with necrotizing enterocolitis (NEC). In this study, we assessed the influence of PDA on NEC outcomes.MethodsA retrospective study of 131 infants with established NEC was performed. Outcomes (death, disease severity, need for surgery, hospitalization duration), as well as multiple clinical parameters were compared between NEC patients with no congenital heart disease (n=102) and those with isolated PDA (n=29). Univariate, multivariate and stepwise logistic regression analyses were performed.ResultsBirth weight and gestational age were significantly lower in patients with PDA [median (95% CI): 1120 g (1009-1562 g), 28.4 wk (27.8-30.5 wk)] than in those without PDA [median (95% CI): 1580 g (1593-1905 g), 32.4 wk (31.8-33.5 wk); P<0.05]. The risk of NEC-attributable fatality was higher in NEC patients with PDA (35%) than in NEC patients without PDA (14%)[univariate odds ratio (OR)=3.3, 95% CI: 1.8-8.6, P<0.05; multivariate OR=2.4, 95% CI: 0.82-2.39, P=0.111]. Significant independent predictors for nonsurvival within the entire cohort were advanced disease severity stage III (OR=27.9, 95% CI: 7.4-105, P<0.001) and birth weight below 1100 g (OR=5.7, 95% CI: 1.7-19.4, P<0.01).ConclusionsIn patients with NEC, the presence of PDA is associated with an increased risk of death. However, when important differences between the two study groups are controlled, only birth weight and disease severity may independently predict mortality.


Archive | 2015

Fractures in Children and Adolescents

Christoph Nau; Ingo Marzi; Kai Ziebarth; Steffen Michael Berger

Fractures of the growing bone require fixation techniques, which preclude any injury to the growth plate regions. This requirement is met by Elastic Stable Intramedullary Nails (ESIN) which are positioned between both metaphyseal regions. Pronounced malposition and/or shortening, open fractures and fractures with impending skin perforation are indications for clavicle nailing in adolescents. Retrograde nailing with two elastic nails, inserted from lateral, is the method of choice for stabilization of humerus fractures. In radial neck fractures with severe tilting of the radial head, a retrograde nail may reduce and fix the head. In Monteggia lesions, the ulna fracture is reduced and fixed with an antegrade nail. Forearm fractures with unacceptable axial deviation are reduced and fixed with one antegrade nail in the ulna and a retrograde nail in the radius. Ascending elastic nailing is done for femur shaft and proximal femur fractures. The medial and lateral entry sites are located above the distal physis. End caps are used to prevent shortening in spiral and multiple segment fractures. Fractures of the distal third of the femur are nailed in a descending technique. The entry sites of two nails are located on the lateral cortex below the greater trochanter. Combined tibia and fibula fractures, open fractures and unstable fracture types such as spiral and multifragmental tibia fractures are good indications for ESIN. Descending nailing is the method of choice. The nail entry points are medially and laterally distal to the apophysis of the proximal tibia. Thorough knowledge of each fracture type, fracture location and age specific healing pattern is necessary for safe and effective treatment of pediatric fractures.


Brain Injury | 2015

Acute S100B in serum is associated with cognitive symptoms and memory performance 4 months after paediatric mild traumatic brain injury

Martina Studer; Barbara Goeggel Simonetti; Theda Heinks; Maja Steinlin; Alexander Leichtle; Steffen Michael Berger; Alexander Joeris

Abstract Objective: This study explored whether acute serum marker S100B is related with post-concussive symptoms (PCS) and neuropsychological performance 4 months after paediatric mild traumatic brain injury (mTBI). Research design and methods: This prospective short-term longitudinal study investigated children (aged 6–16 years) with mTBI (n = 36, 16 males) and children with orthopaedic injuries (OI, n = 27, 18 males) as a control group. S100B in serum was measured during the acute phase and was correlated with parent-rated PCS and neuropsychological performance 4 months after the injury. Main outcomes and results: The results revealed no between-group difference regarding acute S100B serum concentration. In children after mTBI, group-specific significant Spearman correlations were found between S100B and post-acute cognitive PCS (r = 0.54, p = 0.001) as well as S100B and verbal memory performance (r = −0.47, p = 0.006). In children after OI, there were insignificant positive relations between S100B and post-acute somatic PCS. In addition, insignificant positive correlations were found between neuropsychological outcome and S100B in children after OI. Conclusions: S100B was not specific for mild brain injuries and may also be elevated after OI. The group-specific association between S100B and ongoing cognitive PCS in children after mTBI should motivate to examine further the role of S100B as a diagnostic biomarker in paediatric mTBI.


The Journal of Pediatrics | 2010

Clostridium perfringens and necrotizing enterocolitis

Luregn J. Schlapbach; Olaf Ahrens; Peter Michael Klimek; Steffen Michael Berger; Ulf Kessler

regimens evaluated, extensively hydrolyzed protein formula with and without the addition of lactobacillus GG. If baseline values were artificially higher because of the presence of blood, it should have affected stools from both dietary groups equally and thus had no impact on results. Savino et al state that we did not clarify whether patients had anal fissures or gastroesophageal reflux. None of the patients studied had anal fissures, and we are not sure why gastroesophageal reflux had to be ruled out in infants whose only symptoms were blood and mucus in the stool. Finally, Savino et al state that they found higher FC levels in breastfed infants compared with formula-fed infants. That seems to be in contrast with the findings of Campeotto et al, who reported no differences related to type of feeding.

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