Michael Ebsen - Academia.edu (original) (raw)

Papers by Michael Ebsen

Abbreviations: AFC, alveolar fluid clearance; BPD, bronchopulmonary dysplasia; E2, 17-␤-estradiol... more Abbreviations: AFC, alveolar fluid clearance; BPD, bronchopulmonary dysplasia; E2, 17-␤-estradiol (pg/mL ϫ 3.671 ϭ pmol/L); ENaC, epithelial sodium channel; ICI 182.780, 7␣-[9-[(4,4,5,5,5-pentafluoropentyl)sulfinyl] nonyl]-estra-1,3,5(10)-triene-3,1 7␤-diol; P, progesterone (ng/mL ϫ 3.18 ϭ nmol/L); RTI 3021-022,

The International journal of oral & maxillofacial implants

Risk factors and complications in immediate implant placement are widely discussed. The present r... more Risk factors and complications in immediate implant placement are widely discussed. The present report describes a case of severe osteomyelitis as a serious complication after the immediate placement of a dental implant into an extraction socket of a 61-year-old woman. The course leads from initial treatment of recurrent perimandibular abscesses with surgical drainage and high-dose intravenous antibiotics to a refractory osteomyelitis. Hemimandibulectomy and partial mandibular reconstruction with a free fibular flap followed.

Zeitschrift für Geburtshilfe und Neonatologie, 2007

Zeitschrift für Gastroenterologie, 2011

Pseudotumours of the liver are rare entities, which cannot be differentiated from malignant liver... more Pseudotumours of the liver are rare entities, which cannot be differentiated from malignant liver lesions by contrast-enhanced ultrasound (CEUS) or radiological imaging. We report of a 22-year-old man with persistant abdominal pain and fever after appendectomy. Fundamental ultrasound showed an inflammatory swelling of the terminal ileum, suspicious of Crohn's disease as well as two solid liver lesions and left portal vein thrombosis. The enhancement patterns of both liver tumors on CEUS showed inhomogeneous isoenhancement during the arterial and portal phases and hypoenhancement during the late phase, mimiking malignant lesions. Ultrasound-guided biopsy, histology and follow-up, however, confirmed the diagnosis of hepatic inflammatory pseudotumour (IPT). When diagnosing a pseudotumour of the liver, the rare coincidence with chronic inflammatory bowel disease should be considered.

PLoS ONE, 2011

Background: Ventilation using low tidal volumes with permission of hypercapnia is recommended to ... more Background: Ventilation using low tidal volumes with permission of hypercapnia is recommended to protect the lung in acute respiratory distress syndrome. However, the most lung protective tidal volume in association with hypercapnia is unknown. The aim of this study was to assess the effects of different tidal volumes with associated hypercapnia on lung injury and gas exchange in a model for acute respiratory distress syndrome.

Pathology - Research and Practice, 2002

Biology of the Neonate, 2005

Preterm infants with intrauterine growth retardation (IUGR) reveal an increased risk for the deve... more Preterm infants with intrauterine growth retardation (IUGR) reveal an increased risk for the development of acute and chronic pulmonary disorders, i.e. bronchopulmonary dysplasia (BPD). In order to investigate the effect of IUGR on pulmonary development, an easily reproducible animal model for fetal growth restriction has been established using hypoxia as a sole intervention in the last third of pregnancy. Date-mated mice were randomly assigned to either being kept at a fraction of inspired oxygen (FiO2) of 0.10 (hypoxic group) starting at day 14 or under normoxic conditions until day 17.5 of gestation (control group). Variables of somatic growth were assessed and standardized histomorphometric analyses of pulmonary tissue were performed. Expression of surfactant proteins (SP)-A, -B, -C and -D was determined by quantitative rt-PCR as biochemical indicators for lung development and maturation. Fetuses were delivered preterm at 0.87 of gestation. Those grown under hypoxic conditions revealed significantly lower birth weights (median: 0.69 vs. 0.97 g in controls; p < 0.001), body lengths (median: 17.5 vs. 20.2 mm in controls; p < 0.001) and fronto-occipital diameters (median: 9.4 vs. 10.1 mm in controls; p < 0.001) compared to controls. Histomorphometric analyses were found to be without significant differences between both groups. On the transcriptional level, however, mRNA expression of SP-A, -B and -C but not SP-D could be shown to be significantly reduced in hypoxic fetuses compared to normoxic controls. In conclusion, hypoxic conditions from day 14 to 17.5 led to IUGR in preterm mice and to significant alterations of the developing surfactant system. We speculate restricted development of SP gene expression to be a causal factor for the increased risk of acute and chronic pulmonary disorders in preterm infants with IUGR.

Biology of the Neonate, 2006

Different types of surfactant preparations were shown not to exert uniform response in preterm in... more Different types of surfactant preparations were shown not to exert uniform response in preterm infants suffering from respiratory distress syndrome (RDS). Therefore, the effects of a recombinant surfactant protein C (rSP-C) based preparation and a natural surfactant were compared applying different levels of positive end-expiratory pressure (PEEP) in experimental RDS. Preterm rabbits (n = 7-14 per group; 27 days gestation; term 30 days) were randomized for receiving either 100 mg/kg rSP-C or natural bovine surfactant and were compared with saline treated controls. Animals were ventilated for 30 min with either 0.3 or 0 kPa PEEP at standardized tidal volumes and lung mechanics were measured as well as lung histology and mRNA expression of surfactant associated proteins B and C by real-time PCR. The PEEP level applied (0.3 vs. 0 kPa) largely influenced dynamic compliance after administration of rSP-C surfactant (4.45 vs. 2.58 ml/kg), whereas natural surfactant improved compliance regardless of the PEEP applied (4.86 vs. 4.24 ml/kg) compared to controls (2.41 vs. 1.55 ml/kg). Accordingly, administration of PEEP significantly increased alveolar count in all groups as well as SP-C mRNA expression, whereas SP-B expression and protein content both remained unchanged. Response to rSP-C surfactant depends on the PEEP level applied in our model of neonatal RDS. These findings should be considered for the conception of clinical trials regarding treatment strategies in neonatal RDS.

International Journal of Medical Microbiology, 2006

Spiroplasmas are helical mycoplasmas which are found in plants and arthropods, also in ticks. Som... more Spiroplasmas are helical mycoplasmas which are found in plants and arthropods, also in ticks. Some Spiroplasma species are incriminated as potential pathogens for vertebrates. During a study on Q fever in North Rhine-Westphalia, an intracellularly growing microorganism could be isolated from a pool of Ixodes ticks. The agent replicated within cytoplasmic vacuoles similar to those of Coxiella burnetii. PCR using coxiellae-, ehrlichiae-or chlamydiae-specific primers showed that agent Z/16 was distinct from these bacteria. In contrast to coxiellae or chlamydiae, the agent could not be stained according to the method of Gime´nez. Also electron microscopy provided evidence that the isolate Z/16 is different from coxiellae and chlamydiae. Determination of 16S ribosomal RNA gene sequences provided evidence that the isolate Z/16 can be classified as Spiroplasma sp. To our knowledge, this is the first report of an isolation of a Spiroplasma strain using a mammalian cell line. The pathogenic potential of the organism needs further investigation.

Intensive Care Medicine, 2003

The online version of the original article can be found at http:// dx.

Infection and Immunity, 2005

Staphylococcus saprophyticus surface-associated protein (Ssp) was the first surface protein descr... more Staphylococcus saprophyticus surface-associated protein (Ssp) was the first surface protein described for this organism. Ssp-positive strains display a fuzzy layer of surface-associated material in electron micrographs, whereas Ssp-negative strains appear to be smooth. The physiologic function of Ssp, however, has remained elusive. To clone the associated gene, we determined the N-terminal sequence, as well as an internal amino acid sequence, of the purified protein. We derived two degenerate primers from these peptide sequences, which we used to identify the ssp gene from genomic DNA of S. saprophyticus 7108. The gene was cloned by PCR techniques and was found to be homologous to genes encoding staphylococcal lipases. In keeping with this finding, strains 7108 and 9325, which are Ssp positive, showed lipase activity on tributyrylglycerol agar plates, whereas the Ssp-negative strain CCM883 did not. Association of enzyme activity with the cloned DNA was proven by introducing the gene into Staphylococcus carnosus TM300. When wild-type strain 7108 and an isogenic mutant were analyzed by transmission electron microscopy, strain 7108 exhibited the fuzzy surface layer, whereas the mutant appeared to be smooth. Lipase activity and the surface appendages could be restored by reintroduction of the cloned gene into the mutant. Experiments using immobilized collagen type I did not provide evidence for the involvement of Ssp in adherence to this matrix protein. Our experiments thus provided evidence that Ssp is a surface-associated lipase of S. saprophyticus.

Critical Care Medicine, 2006

Meconium aspiration syndrome (MAS) remains a relevant cause of neonatal respiratory failure and i... more Meconium aspiration syndrome (MAS) remains a relevant cause of neonatal respiratory failure and is characterized by severe impairment of pulmonary gas exchange, surfactant inactivation, and pronounced inflammatory changes. Surfactant administration has been shown as an effective treatment strategy in MAS. The present study aimed at investigating the impact of a recombinant surfactant protein (SP)-C-based surfactant on pulmonary gas exchange and lung function in this model of neonatal lung injury. Furthermore, SP-B and -C were determined on the transcriptional and protein level. Laboratory experiment. University laboratory. Twenty three newborn piglets (median age 6 days, weight 1900-2500 g). Piglets were intubated and mechanically ventilated and then received 20% sterile meconium (5 mL/kg) for induction of lung injury. After 30 mins, animals were randomized for control (n = 7, MAS controls), recombinant SP-C surfactant (n = 8), or natural surfactant (n = 8). Surfactant preparations were administered as an intratracheal bolus (75 mg/kg), and animals were ventilated for another 330 mins. Nonventilated newborn piglets at term (n = 28; median weight 1484 g, range 720-1990 g) served as a healthy reference group (healthy controls). Lung function variables, arterial blood gas samples, and lung tissues were obtained. Expression of SP-B and -C messenger RNA was quantified in left lung lobe tissue using real-time polymerase chain reaction. Protein concentrations were determined by enzyme-linked immunosorbent assay. Scanning electron microscopy and transmission electron microscopy were performed in tissue samples of the right lung lobe. Compared with healthy controls, SP-B messenger RNA expression was significantly increased in MAS (p < .02), whereas SP-C messenger RNA expression was found to be significantly reduced (p < .001). SP concentrations, however, were not significantly different. Although a significant improvement of gas exchange and lung function was observed after surfactant administration in both groups, surfactant messenger RNA expression and protein concentrations were not significantly altered. Scanning and transmission electron microscopy showed severe pulmonary ultrastructural changes after meconium aspiration improving after surfactant treatment. Impairment of lung function in MAS, associated with marked changes in SP messenger RNA expression, can be sufficiently treated using recombinant SP-C-based or natural surfactant. Despite improved lung function and gas exchange as well as pulmonary ultrastructure after treatment, pulmonary SP messenger RNA expression and concentrations remained significantly affected, giving important insight into the time course following surfactant treatment in MAS.

BMC Pulmonary Medicine, 2008

Background: Several concepts of treatment in neonatal ARDS have been proposed in the last years. ... more Background: Several concepts of treatment in neonatal ARDS have been proposed in the last years. The present study compared the effects of open lung concept positive pressure ventilation (PPV OLC ) with a conventional ventilation strategy combined with administration of two different surfactant preparations on lung function and surfactant homoeostasis.

Auris Nasus Larynx, 2006

This case report deals with the case of an 86-year-old man who was admitted to our hospital with ... more This case report deals with the case of an 86-year-old man who was admitted to our hospital with an submandibular swelling after mastectomy for breast cancer one and a half year ago. Histopathological examination after surgical resection evaluated metastasis of a mixed-type breast carcinoma. Further treatment was palliative chemotherapy. This is the first description of a male breast carcinoma metastasis located in the submandibular region.

Pediatric Research, 2006

Abbreviations: AFC, alveolar fluid clearance; BPD, bronchopulmonary dysplasia; E2, 17-␤-estradiol... more Abbreviations: AFC, alveolar fluid clearance; BPD, bronchopulmonary dysplasia; E2, 17-␤-estradiol (pg/mL ϫ 3.671 ϭ pmol/L); ENaC, epithelial sodium channel; ICI 182.780, 7␣-[9-[(4,4,5,5,5-pentafluoropentyl)sulfinyl] nonyl]-estra-1,3,5(10)-triene-3,1 7␤-diol; P, progesterone (ng/mL ϫ 3.18 ϭ nmol/L); RTI 3021-022,

Abbreviations: AFC, alveolar fluid clearance; BPD, bronchopulmonary dysplasia; E2, 17-␤-estradiol... more Abbreviations: AFC, alveolar fluid clearance; BPD, bronchopulmonary dysplasia; E2, 17-␤-estradiol (pg/mL ϫ 3.671 ϭ pmol/L); ENaC, epithelial sodium channel; ICI 182.780, 7␣-[9-[(4,4,5,5,5-pentafluoropentyl)sulfinyl] nonyl]-estra-1,3,5(10)-triene-3,1 7␤-diol; P, progesterone (ng/mL ϫ 3.18 ϭ nmol/L); RTI 3021-022,

The International journal of oral & maxillofacial implants

Risk factors and complications in immediate implant placement are widely discussed. The present r... more Risk factors and complications in immediate implant placement are widely discussed. The present report describes a case of severe osteomyelitis as a serious complication after the immediate placement of a dental implant into an extraction socket of a 61-year-old woman. The course leads from initial treatment of recurrent perimandibular abscesses with surgical drainage and high-dose intravenous antibiotics to a refractory osteomyelitis. Hemimandibulectomy and partial mandibular reconstruction with a free fibular flap followed.

Zeitschrift für Geburtshilfe und Neonatologie, 2007

Zeitschrift für Gastroenterologie, 2011

Pseudotumours of the liver are rare entities, which cannot be differentiated from malignant liver... more Pseudotumours of the liver are rare entities, which cannot be differentiated from malignant liver lesions by contrast-enhanced ultrasound (CEUS) or radiological imaging. We report of a 22-year-old man with persistant abdominal pain and fever after appendectomy. Fundamental ultrasound showed an inflammatory swelling of the terminal ileum, suspicious of Crohn's disease as well as two solid liver lesions and left portal vein thrombosis. The enhancement patterns of both liver tumors on CEUS showed inhomogeneous isoenhancement during the arterial and portal phases and hypoenhancement during the late phase, mimiking malignant lesions. Ultrasound-guided biopsy, histology and follow-up, however, confirmed the diagnosis of hepatic inflammatory pseudotumour (IPT). When diagnosing a pseudotumour of the liver, the rare coincidence with chronic inflammatory bowel disease should be considered.

PLoS ONE, 2011

Background: Ventilation using low tidal volumes with permission of hypercapnia is recommended to ... more Background: Ventilation using low tidal volumes with permission of hypercapnia is recommended to protect the lung in acute respiratory distress syndrome. However, the most lung protective tidal volume in association with hypercapnia is unknown. The aim of this study was to assess the effects of different tidal volumes with associated hypercapnia on lung injury and gas exchange in a model for acute respiratory distress syndrome.

Pathology - Research and Practice, 2002

Biology of the Neonate, 2005

Preterm infants with intrauterine growth retardation (IUGR) reveal an increased risk for the deve... more Preterm infants with intrauterine growth retardation (IUGR) reveal an increased risk for the development of acute and chronic pulmonary disorders, i.e. bronchopulmonary dysplasia (BPD). In order to investigate the effect of IUGR on pulmonary development, an easily reproducible animal model for fetal growth restriction has been established using hypoxia as a sole intervention in the last third of pregnancy. Date-mated mice were randomly assigned to either being kept at a fraction of inspired oxygen (FiO2) of 0.10 (hypoxic group) starting at day 14 or under normoxic conditions until day 17.5 of gestation (control group). Variables of somatic growth were assessed and standardized histomorphometric analyses of pulmonary tissue were performed. Expression of surfactant proteins (SP)-A, -B, -C and -D was determined by quantitative rt-PCR as biochemical indicators for lung development and maturation. Fetuses were delivered preterm at 0.87 of gestation. Those grown under hypoxic conditions revealed significantly lower birth weights (median: 0.69 vs. 0.97 g in controls; p < 0.001), body lengths (median: 17.5 vs. 20.2 mm in controls; p < 0.001) and fronto-occipital diameters (median: 9.4 vs. 10.1 mm in controls; p < 0.001) compared to controls. Histomorphometric analyses were found to be without significant differences between both groups. On the transcriptional level, however, mRNA expression of SP-A, -B and -C but not SP-D could be shown to be significantly reduced in hypoxic fetuses compared to normoxic controls. In conclusion, hypoxic conditions from day 14 to 17.5 led to IUGR in preterm mice and to significant alterations of the developing surfactant system. We speculate restricted development of SP gene expression to be a causal factor for the increased risk of acute and chronic pulmonary disorders in preterm infants with IUGR.

Biology of the Neonate, 2006

Different types of surfactant preparations were shown not to exert uniform response in preterm in... more Different types of surfactant preparations were shown not to exert uniform response in preterm infants suffering from respiratory distress syndrome (RDS). Therefore, the effects of a recombinant surfactant protein C (rSP-C) based preparation and a natural surfactant were compared applying different levels of positive end-expiratory pressure (PEEP) in experimental RDS. Preterm rabbits (n = 7-14 per group; 27 days gestation; term 30 days) were randomized for receiving either 100 mg/kg rSP-C or natural bovine surfactant and were compared with saline treated controls. Animals were ventilated for 30 min with either 0.3 or 0 kPa PEEP at standardized tidal volumes and lung mechanics were measured as well as lung histology and mRNA expression of surfactant associated proteins B and C by real-time PCR. The PEEP level applied (0.3 vs. 0 kPa) largely influenced dynamic compliance after administration of rSP-C surfactant (4.45 vs. 2.58 ml/kg), whereas natural surfactant improved compliance regardless of the PEEP applied (4.86 vs. 4.24 ml/kg) compared to controls (2.41 vs. 1.55 ml/kg). Accordingly, administration of PEEP significantly increased alveolar count in all groups as well as SP-C mRNA expression, whereas SP-B expression and protein content both remained unchanged. Response to rSP-C surfactant depends on the PEEP level applied in our model of neonatal RDS. These findings should be considered for the conception of clinical trials regarding treatment strategies in neonatal RDS.

International Journal of Medical Microbiology, 2006

Spiroplasmas are helical mycoplasmas which are found in plants and arthropods, also in ticks. Som... more Spiroplasmas are helical mycoplasmas which are found in plants and arthropods, also in ticks. Some Spiroplasma species are incriminated as potential pathogens for vertebrates. During a study on Q fever in North Rhine-Westphalia, an intracellularly growing microorganism could be isolated from a pool of Ixodes ticks. The agent replicated within cytoplasmic vacuoles similar to those of Coxiella burnetii. PCR using coxiellae-, ehrlichiae-or chlamydiae-specific primers showed that agent Z/16 was distinct from these bacteria. In contrast to coxiellae or chlamydiae, the agent could not be stained according to the method of Gime´nez. Also electron microscopy provided evidence that the isolate Z/16 is different from coxiellae and chlamydiae. Determination of 16S ribosomal RNA gene sequences provided evidence that the isolate Z/16 can be classified as Spiroplasma sp. To our knowledge, this is the first report of an isolation of a Spiroplasma strain using a mammalian cell line. The pathogenic potential of the organism needs further investigation.

Intensive Care Medicine, 2003

The online version of the original article can be found at http:// dx.

Infection and Immunity, 2005

Staphylococcus saprophyticus surface-associated protein (Ssp) was the first surface protein descr... more Staphylococcus saprophyticus surface-associated protein (Ssp) was the first surface protein described for this organism. Ssp-positive strains display a fuzzy layer of surface-associated material in electron micrographs, whereas Ssp-negative strains appear to be smooth. The physiologic function of Ssp, however, has remained elusive. To clone the associated gene, we determined the N-terminal sequence, as well as an internal amino acid sequence, of the purified protein. We derived two degenerate primers from these peptide sequences, which we used to identify the ssp gene from genomic DNA of S. saprophyticus 7108. The gene was cloned by PCR techniques and was found to be homologous to genes encoding staphylococcal lipases. In keeping with this finding, strains 7108 and 9325, which are Ssp positive, showed lipase activity on tributyrylglycerol agar plates, whereas the Ssp-negative strain CCM883 did not. Association of enzyme activity with the cloned DNA was proven by introducing the gene into Staphylococcus carnosus TM300. When wild-type strain 7108 and an isogenic mutant were analyzed by transmission electron microscopy, strain 7108 exhibited the fuzzy surface layer, whereas the mutant appeared to be smooth. Lipase activity and the surface appendages could be restored by reintroduction of the cloned gene into the mutant. Experiments using immobilized collagen type I did not provide evidence for the involvement of Ssp in adherence to this matrix protein. Our experiments thus provided evidence that Ssp is a surface-associated lipase of S. saprophyticus.

Critical Care Medicine, 2006

Meconium aspiration syndrome (MAS) remains a relevant cause of neonatal respiratory failure and i... more Meconium aspiration syndrome (MAS) remains a relevant cause of neonatal respiratory failure and is characterized by severe impairment of pulmonary gas exchange, surfactant inactivation, and pronounced inflammatory changes. Surfactant administration has been shown as an effective treatment strategy in MAS. The present study aimed at investigating the impact of a recombinant surfactant protein (SP)-C-based surfactant on pulmonary gas exchange and lung function in this model of neonatal lung injury. Furthermore, SP-B and -C were determined on the transcriptional and protein level. Laboratory experiment. University laboratory. Twenty three newborn piglets (median age 6 days, weight 1900-2500 g). Piglets were intubated and mechanically ventilated and then received 20% sterile meconium (5 mL/kg) for induction of lung injury. After 30 mins, animals were randomized for control (n = 7, MAS controls), recombinant SP-C surfactant (n = 8), or natural surfactant (n = 8). Surfactant preparations were administered as an intratracheal bolus (75 mg/kg), and animals were ventilated for another 330 mins. Nonventilated newborn piglets at term (n = 28; median weight 1484 g, range 720-1990 g) served as a healthy reference group (healthy controls). Lung function variables, arterial blood gas samples, and lung tissues were obtained. Expression of SP-B and -C messenger RNA was quantified in left lung lobe tissue using real-time polymerase chain reaction. Protein concentrations were determined by enzyme-linked immunosorbent assay. Scanning electron microscopy and transmission electron microscopy were performed in tissue samples of the right lung lobe. Compared with healthy controls, SP-B messenger RNA expression was significantly increased in MAS (p < .02), whereas SP-C messenger RNA expression was found to be significantly reduced (p < .001). SP concentrations, however, were not significantly different. Although a significant improvement of gas exchange and lung function was observed after surfactant administration in both groups, surfactant messenger RNA expression and protein concentrations were not significantly altered. Scanning and transmission electron microscopy showed severe pulmonary ultrastructural changes after meconium aspiration improving after surfactant treatment. Impairment of lung function in MAS, associated with marked changes in SP messenger RNA expression, can be sufficiently treated using recombinant SP-C-based or natural surfactant. Despite improved lung function and gas exchange as well as pulmonary ultrastructure after treatment, pulmonary SP messenger RNA expression and concentrations remained significantly affected, giving important insight into the time course following surfactant treatment in MAS.

BMC Pulmonary Medicine, 2008

Background: Several concepts of treatment in neonatal ARDS have been proposed in the last years. ... more Background: Several concepts of treatment in neonatal ARDS have been proposed in the last years. The present study compared the effects of open lung concept positive pressure ventilation (PPV OLC ) with a conventional ventilation strategy combined with administration of two different surfactant preparations on lung function and surfactant homoeostasis.

Auris Nasus Larynx, 2006

This case report deals with the case of an 86-year-old man who was admitted to our hospital with ... more This case report deals with the case of an 86-year-old man who was admitted to our hospital with an submandibular swelling after mastectomy for breast cancer one and a half year ago. Histopathological examination after surgical resection evaluated metastasis of a mixed-type breast carcinoma. Further treatment was palliative chemotherapy. This is the first description of a male breast carcinoma metastasis located in the submandibular region.

Pediatric Research, 2006

Abbreviations: AFC, alveolar fluid clearance; BPD, bronchopulmonary dysplasia; E2, 17-␤-estradiol... more Abbreviations: AFC, alveolar fluid clearance; BPD, bronchopulmonary dysplasia; E2, 17-␤-estradiol (pg/mL ϫ 3.671 ϭ pmol/L); ENaC, epithelial sodium channel; ICI 182.780, 7␣-[9-[(4,4,5,5,5-pentafluoropentyl)sulfinyl] nonyl]-estra-1,3,5(10)-triene-3,1 7␤-diol; P, progesterone (ng/mL ϫ 3.18 ϭ nmol/L); RTI 3021-022,