Notch receptors in human choroid plexus tumors.

Notch signaling plays a role in development and formation of the normal choroid plexus (nCP), and in formation of various tumors in humans. Activation of Notch3 has been reported to promote tumor growth in invasive gliomas and to initiate formation of choroid plexus tumors (CPT) in mice. We investigated the expression of all currently known Notch receptors (Notch 1-4) in 55 samples of nCP and 88 CPT, including 61 choroid plexus papillomas (CPP), 22 atypical CPP and 5 choroid plexus carcinomas by immunohistochemistry. Notch expression was semiquantitatively evaluated separately for membranous/cytoplasmic and for nuclear staining. In addition, we examined Her2 expression (EGFR2, Her2/neu, ErbB2, CD340) because of its functional link to Notch signaling. All samples were negative for Notch3. Membranous/cytoplasmic expression of Notch1 (p<0.0001) and Notch4 (p=0.046) was significantly higher, whereas Notch2 expression was significantly lower (p<0.0001) in nCP compared to CPT. Nuclear expression of Notch1, -2 and -4 was significantly higher in CPT compared to nCP (p<0.0001 each). Expression of Notch2 and Notch4 showed a shift from a prevailing membranous/cytoplasmic expression in nCP to a predominant nuclear expression in CPT. Her2 was weakly expressed in 42/84 CPT but only in 2/53 nCP (p=0.0001) and positively correlated with nuclear expression of Notch1, -2 and 4 in CPT. In summary, a shift between membranous/cytoplasmic (non-canonical signaling pathway) and nuclear expression (canonical signaling pathway) of Notch1, -2 and -4 and upregulation of Her2 indicate neoplastic transformation in human CP and may reveal new therapeutic approaches.

De novo expression of the hemoglobin scavenger receptor CD163 by activated microglia is not associated with hemorrhages in human brain lesions.

The main function of CD163 (hemoglobin scavenger receptor) is to bind the hemoglobin-haptoglobin complex, thereby mediating extravasal hemolysis. However, CD163 also has an antiinflammatory function. After CD163-mediated endocytosis, hemoglobin is catabolized further by hemeoxygenase 1 (HO-1). Previously, we found expression of HO-1 to be restricted to microglia/macrophages at sites of hemorrhages in human traumatic and ischemic brain lesions. We now investigated if CD163 expression is also correlated with hemorrhages in brain lesions. Methods. Autopsy brain tissue from 44 cases with hemorrhagic brain lesions (32 traumatic brain injuries/TBI, 12 intracerebral bleedings/ICB), 56 non-hemorrhagic brain lesions (30 ischemias, 26 hypoxias) and 6 control brains were investigated. The post injury survival times ranged from a few minutes to 60 months. Results. In controls, single perivascular monocytes expressed CD163, but only single CD163+ microglia were found in 3/6 cases. CD163+ cells in the parenchyma (activated microglia/macrophages) increased significantly within 24 hours after trauma and ischemia and within 1-7 days following ICB or hypoxia. Overall, significantly lower and higher levels of parenchymal CD163+ cells occurred in hypoxia and ischemia, respectively. Perivascular CD163+ cells also increased significantly in all pathological conditions. In areas remote from circumscribed brain lesions (TBI, ICB, ischemia), significant changes were only found in ICB and ischemia. Conclusions. De novo expression of CD163 by activated microglia/macrophages and CD163+ infiltrating monocytes are neither restricted to nor predominant in hemorrhagic brain lesions. Thus, the antiinflammatory function of CD163 probably predominates, both in hemorrhagic and non-hemorrhagic brain lesions and points to possible immunomodulatory treatment strategies targeting CD163.

No evidence for WT1 involvement in a beta-catenin-independent activation of the Wnt signaling pathway in pituitary adenomas.

The overexpression of Wilms' tumor gene product WT1, which acts as a tumor suppressor or oncogene, has been reported in various malignancies. Recent studies have shown that the interaction partner Wnt-4 is upregulated in pituitary adenomas dependent on the Pit-1 lineage (somatotrophs, lactotrophs, and thyrotrophs). However, no data on WT1 expression in nontumorous pituitary tissue or pituitary adenomas is available to date. We investigated WT1 expression in 90 paraffin-embedded pituitary adenomas, including eight atypical adenomas, and in 28 nontumorous pituitary glands by immunohistochemistry. WT1 is absent in epithelial cells of all nontumorous pituitary glands and in 87 out of 90 pituitary adenomas. Only two GHomas (including one atypical adenoma) and one gonadotropin-producing adenoma expressed WT1 in the cytoplasm of single tumor cells without nuclear staining. There is no evidence that WT1 does regulate the Wnt-4/beta-catenin-independent pathway which is activated in the Pit-1-expressing subset of pituitary adenomas.

Reactive astrocytes and activated microglial cells express EAAT1, but not EAAT2, reflecting a neuroprotective potential following ischaemia.

AIMS: Glutamate receptor antagonists have failed clinical stroke trials and it has been proposed that the action of N-methyl D-aspartate receptors is necessary for neuronal survival. Thus, excitatory amino acid transporters (EAATs) might be a promising therapeutic target. The aim of this study was to investigate glial expression of EAATs following ischaemia. METHODS AND RESULTS: Expression of EAAT1 (GLAST) and EAAT2 (Glt-1) in 24 cases of ischaemia was examined by immunohistochemistry. Cortical expression of both EAATs in the lesion decreased within 24 h (P < 0.01, each). Whereas EAAT1+ white matter cells increased 18-fold (P < 0.05) within 24 h in the lesion and remained elevated for months in adjacent (469-fold, P < 0.01) and remote areas (20-fold, P < 0.05), EAAT2+ white matter cells were equivalent in ischaemia and controls. In the first week after stroke mainly activated (ramified and amoeboid) microglia expressed EAAT1, whereas monocytic cells in perivascular spaces and foamy macrophages lacked EAAT1. After more than 1 week, predominantly reactive astrocytes expressed EAAT1. CONCLUSIONS: Microglial EAAT1 expression is restricted to the early/intermediate stage of activation and blood-derived (perivascular) monocytes do not contribute to EAAT1+ cells following ischaemia. Whether a pharmacological increase in glial EAAT expression may compensate for loss of cortical EAAT expression and reduce neuronal damage following stroke requires investigation by further functional studies.

Expression of EAAT1 reflects a possible neuroprotective function of reactive astrocytes and activated microglia following human traumatic brain injury.

UNLABELLED: Glutamate-mediated excitotoxicity is known to cause secondary brain damage following stroke and traumatic brain injury (TBI). However, clinical trials using NMDA antagonists failed. Thus, glial excitatory amino acid transporters (EAATs) might be a promising target for therapeutic intervention. METHODS AND RESULTS: We examined expression of EAAT1 (GLAST) and EAAT2 (Glt-1) in 36 TBI cases by immunohistochemistry. Cortical expression of both EAATs decreased rapidly and widespread throughout the brain (in lesional, adjacent and remote areas) following TBI. In the white matter numbers of EAAT1+ parenchymal cells increased 39-fold within 24h (p<0.001) and remained markedly elevated till later stages in the lesion (90-fold, p<0.01) and in peri-lesional regions (86-fold, p<0.01). In contrast, EAAT2+ parenchymal cells and EAAT1+ or EAAT2+ perivascular cells did not increase significantly. Within the first days following TBI mainly activated microglia and thereafter mainly reactive astrocytes expressed EAAT1. Perivascular monocytes and foamy macrophages lacked EAAT1 immunoreactivity. We conclude that following TBI i) loss of cortical EAATs contributes to secondary brain damage, ii) glial EAAT1 expression reflects a potential neuroprotective function of microglia and astrocytes, iii) microglial EAAT1 expression is restricted to an early stage of activation, iv) blood-derived monocytes do not express EAAT1 and v) pharmacological modification of glial EAAT expression might further limit neuronal damage.

Upregulation of frizzled 9 in astrocytomas.

Wnt/frizzled (FZD) cascades play important roles in controlling cell fate, proliferation, migration, tissue architecture and organogenesis during embryonic development and in adult organisms. The potential involvement of this pathway in tumorigenesis has been established in several types of cancers. Frizzled 9 (FZD9) is expressed in brain and its aberrant expression in gastric cancer was observed. However, its association with astrocytomas remains unknown therefore we studied FZD9 expression in astrocytomas of different malignancy. In the present study, FZD9 expression in 25 astrocytomas was investigated using immunohistochemistry with specific antibodies. Further FZD9 expression in native human brain tissue and glioblastoma cell line were analysed using real-time reverse transcription polymerase chain reaction (RT-PCR). In human astrocytomas, FZD9 immunoreactivity (IR) was observed in both microvessels and neoplastic cells. The percentage of FZD9+ microvessels in relation to FZD9+ vessels was significantly higher in malignant astrocytomas than in low-grade astrocytomas and positively correlated with the astrocytoma World Health Organization (WHO) grading (r = 1, P = 0.04). Furthermore, the FZD9 IR scores positively correlated with astrocytoma WHO grading (r = 1, P = 0.04) and proliferating activity (r = 0.77, P < 0.001). Real-time RT-PCR data showed that FZD9 expression in human glioblastoma was significant higher than in normal brain (P < 0.05) but FZD9 expression was only slightly induced in cobalt chloride-treated human glioblastoma T98G cells compared with untreated cells (P > 0.05). FZD9 is upregulated in astrocytomas, suggesting that FZD9 could be important in the tumorigenesis of human astrocytomas.

Early infiltration of CD8+ macrophages/microglia to lesions of rat traumatic brain injury.

Local inflammatory responses play an important role in mediating secondary tissue damage in traumatic brain injury. Characterization of leukocytic subpopulations contributing to the early infiltration of the damaged tissue might aid in further understanding of lesion development and contribute to definition of cellular targets for selective immunotherapy. In a rat traumatic brain injury model, significant CD8+ cell accumulation was observed 3 days post-injury. The CD8+ cells were strictly distributed to the pannecrotic areas and around the pannecrotic perimeter. The morphology, time course of accumulation and distribution of CD8+ cells were similar to that of reactive ED1+ and endothelial monocyte-activating polypeptide II+ microglia/macrophages, but different from W3/13+ T cells. Further double-labeling experiments confirmed that the major cellular sources of CD8 were reactive macrophages/microglia. Both the location of these CD8+ macrophages/microglia to the border of the pannecrosis and their co-expression of endothelial monocyte-activating polypeptide II and P2X4 receptor suggest they might have a central role in lesion development and might thus be candidates for development of immunotherapeutic, anti-inflammatory strategies.

Bone morphogenetic protein-6 is expressed early by activated astrocytes in lesions of rat traumatic brain injury.

We have analyzed early expression of bone morphogenetic protein-6 in rat brains subjected to traumatic brain injury. Bone morphogenetic protein-6 was expressed in neurons of the hippocampus and cortex in normal adult rat brains. A pronounced expression of bone morphogenetic protein-6 in astroglia located to the lesion became obvious 48 h postinjury. Bone morphogenetic protein-6(+) glia were distributed around the lesion, thus demarcating the injured tissue from normal brain. Double labeling by immunohistochemistry revealed that the major glial sources for bone morphogenetic protein-6 were reactive astrocytes and few ED1(+) or W3/13(+) cells co-expressed bone morphogenetic protein-6. Furthermore, bone morphogenetic protein-6 expression in neurons located to hippocampus and cortex of the lesioned hemisphere was up-regulated 3 days postinjury. In conclusion, this is the first description of bone morphogenetic protein-6 expression in traumatic brains. Our data suggest that bone morphogenetic protein-6 might be involved in astrogliosis and neuron protection following traumatic brain injury.

Sonographic prognostic factors in prenatal diagnosis of SCT.

OBJECTIVE: A subset of fetuses with sacrococcygeal teratomas (SCT) develops hydrops caused by high-output heart failure. Identification of fetuses at risk for hydrops is important because surgical intervention may reverse the pathophysiology of the disease. The aim of this study was to evaluate sonographic prognostic factors regarding tumor morphology and vascularity associated with the development of hydrops in utero. METHODS: Over a 10-year period, we identified 7 fetuses with SCT diagnosed antenatally and managed at the University of Mainz. We retrospectively reviewed the charts of mothers and infants and recorded data on prenatal diagnosis, tumor size and localization, perinatal management, neonatal care, and fetal outcome. RESULTS: The diagnosis of SCT was made in all cases by ultrasound. The median gestational age at the time of initial diagnosis was 23 weeks. In 3 cases, signs of fetal heart failure were detected by ultrasound. Pathological blood flow in the venous system was further noted in 2 cases. One fetus developed hydrops. The mean gestational age at delivery was 35 weeks, depending on the presence or absence of maternal or fetal complications. Six infants were delivered by cesarean section, and 1 by vaginal delivery. After fetal stabilization, surgery was performed in 5 of 7 cases. Inadequate ventilation secondary to prematurity was a contributing factor to death in 1 fetus. One fetal intrauterine death occurred at 27 weeks of gestation. CONCLUSION: Pregnancies with antenatally diagnosed fetal SCT necessitate frequent monitoring to ensure the detection of fetal/maternal complications by ultrasound and Doppler ultrasound. The most important prognostic criteria were cardiomegaly, fetal hydrops, and increased preload indexes of the fetal venous system as sign of fetal heart failure. Many studies show that the occurrence of pulsations in the umbilical vein of a hydropic fetus correlates with a poor fetal outcome. The decision on the optimal time of delivery should therefore be made by a multidisciplinary team of specialists.

Cortical neurons of Creutzfeldt-Jakob disease patients express the urokinase-type plasminogen activator receptor.

Plasminogen belongs to the plasminogen activator system of cell signaling proteins and has recently been identified to bind to pathological prion protein PrPSC, but not to its normal conformer, PrPC. Plasminogen binds specifically to the urokinase-type plasminogen activator receptor (uPAR) to promote pericellular proteolysis, regulate integrin function, and mediate cell signaling. By using immunohistochemistry, we observed that significantly more cortical neurons in eight postmortem brains of patients who died with sporadic Creutzfeldt-Jakob disease (CJD) are immunoreactive for uPAR compared with controls. These data provide the pathophysiological basis for detailed analyses of the role of the plasminogen activator system in CJD and related diseases.

[Integrated gynecology: new medical treatments due to psychosomatic methods of evaluation]. / Integrative Frauenheilkunde: neue Behandlungsstrategien dank psychosomatischer Evaluationsmethoden.

OBJECTIVE: Women with gynecologic cancer are confronted with difficult decisions regarding the therapeutic options. The objective of the present paper is to demonstrate the relationship between surgical procedures and the outcome on quality of life and to discuss the implications for patient management. METHODS: Gynecologic patients were assessed in a prospective study with preoperative semistructured interviews and objective assessments (T1), interviews were repeated 4 and 12 months postoperatively (T2, T3). RESULTS: Women planned for hysterectomy with severe complaints indicate a better postoperative quality of life. Cancer patients, however, tend to feel more distressed about the surgical procedure if they could not be treated organ preserving or by reconstructive techniques. Medical interaction is dependent on the patient's anxiety level and mostly important for their quality of life before and after surgery. CONCLUSION: Psychosomatic research is not only necessary to understand the patient's needs before and after surgery but may also serve as an evaluation method of therapeutical options. By this methods we are able to anticipate the medical and psychological consequences of the therapeutic decisions. Future studies will systematically explore the alternating effect of surgical procedures on the patient's well-being.

[Body image in gynecologic patients before and after radical surgery]. / Das Körpererleben gynäkologischer Patientinnen vor und nach radikaler Chirurgie.

After radical gynecologic surgery women are faced with therapy-induced changes of their body. Since 1995, the body images of women who undergo pelvic exenteration, Wertheim-Meigs-operation or hysterectomy are assessed preoperatively and four and twelve months postoperatively. The aim of this multidimensional prospective study is to get basic information for effective counselling and support. One year after hysterectomy women state to have a normal body image. Cancer patients feel less attractive, less self-confident and more discontented in sexuality depending on therapy-induced changes of their bodies. These women could profit from problem-related preoperative counselling. Postoperative counselling offers will be helpful to support women in the process of acceptance of bodily changes and in the reorganisation of their sexual life.

Chromosomal aberrations in sporadic pituitary tumors.

Pituitary adenomas are common intracranial neoplasms that may be hormone-secreting or nonfunctional. Genetic defects associated with some pituitary tumors have been identified, although our understanding of the underlying molecular mechanisms remains incomplete. We have studied 75 sporadic pituitary tumors, representing the major clinical subtypes, by comparative genomic hybridization (CGH) with the aim of assessing for DNA copy number changes. CGH revealed chromosomal imbalances in 34 adenomas (45.3%), whereby gains were 4.9 times more frequently observed than losses. Most of the genetic alterations detected by CGH affected entire chromosomes (108/131, 82.4%). Gain of genetic material was observed predominantly on chromosomes X (24/75, 32%), 19 (12/75, 16%), 12 (6/75, 6.7%), 7 and 9 (5/75, 6.7%), whereas loss of DNA sequences most frequently affected chromosomes 11 (4/75, 5.3%), 13 and 10 (3/75, 4%). There were no significant differences in the CGH results for the individual clinical subtypes of pituitary tumors. These results reveal a nonrandom pattern of chromosomal alterations in pituitary tumors, in particular gains of entire chromosomes, and this may contribute to the development of such neoplasms.

Cyclooxygenase (COX)-1 expressing macrophages/microglial cells and COX-2 expressing astrocytes accumulate during oligodendroglioma progression.

Cyclooxygenases (COX, prostaglandin endoperoxide synthases, PGG/H synthases) are potent mediators of edema, impeding blood flow and immunomodulation in the pathologically altered brain. Two COX iso-enzymes have been associated with brain disease, the constitutively expressed COX-1 and the cytokine-inducible COX-2. We have used single and double labeling immunohistochemistry to analyse COX-1 and COX-2 expression in twenty-six primary WHO grade II oligodendrogliomas, sixteen primary WHO grade III anaplastic oligodendrogliomas, twenty-seven matched recurrences and ten neuropathologically unaltered brains. COX-1 immunoreactivity was predominantly observed in macrophages/microglial cells. The number of COX-1 expressing macrophages/microglial cells was significantly lower in primary oligodendrogliomas than in primary anaplastic oligodendrogliomas (P<0.0001) and in anaplastic oligodendroglioma relapses (P=0.011). Patients with low COX-1 labeling scores in the primary tumors had significantly longer time to progression and overall survival (P=0.0285) than those with high COX-1 labeling scores. COX-2 immunoreactivity was predominantly observed in disseminated neurons and astrocytes. In glioblastoma multiforme relapses, accumulation of COX-2 expressing astrocytes was observed surrounding areas of focal necrosis. The number of COX-2 expressing astrocytes was significantly (P=0.0471) lower in primary oligodendrogliomas than in high grade oligodendroglioma relapses. These data provide convincing evidence for the differential accumulation of cyclooxygenase isoforms during oligodendroglioma progression in vivo.

Heme oxygenase (HO)-1 expressing macrophages/microglial cells accumulate during oligodendroglioma progression.

Heme oxygenase (HO-1, HSP32) catalyzes the oxidation of heme to biliverdin and carbon monoxide, a putative neurotransmitter. In the brain, HO-1 expression has been associated with neuroprotection during oxidative stress and hypoxia. However, consecutive downstream mediation is involved in neoangiogenesis and consequent neoplastic outgrowth. We have analyzed HO-1 expression in 69 oligodendroglioma tissue samples, in rat intracranially transplanted C6 gliomas, and neuropathologically unaltered control brains by immunohistochemistry. Double labeling experiments confirmed the nature of HO-1 expressing cells. Reverse transcription-polymerase chain reaction was used to demonstrate HO-1 gene expression. HO-1 immunoreactivity was predominantly observed in macrophages/microglial cells. The number of HO-1 expressing macrophages/microglial cells was significantly lower in primary oligodendrogliomas than in their matched relapses (P<0.0001) and lower in primary anaplastic oligodendrogliomas than in their relapses (P=0.0006). Prominent accumulation of HO-1 expressing macrophages/microglial cells was observed in perinecrotic areas of both experimental rat and human glioblastoma relapses. HO-1 expressing neurons, macrophages/microglial cells and astrocytes were scattered in areas of infiltrative tumor growth. Surprisingly, HO-1 mRNA was detected in only one glioblastoma multiforme relapse. We conclude from these data that HO-1 expressing macrophages/microglial cells accumulate during oligodendroglioma progression in areas of focal necrosis. However, overall biological function of this phenomenon remains to be determined.

[Diagnosis and therapy of leg and pelvic deep vein thrombosis in pregnancy]. / Diagnostik und Therapie der tiefen Becken-Beinvenenthrombose in der Schwangerschaft.

OBJECTIVE: To establish differences in the management of acute thrombosis in the deep venous system associated with pregnancy in patients undergoing thrombectomy and in patients receiving heparin therapy. MATERIALS AND METHODS: From 1984 to 1995 the course of pregnancy was assessed retrospectively in 26 patients with acute deep vein thrombosis. Thirteen patients underwent thrombectomy with establishment of an arteriovenous fistula and 13 patients received conservative treatment with heparin therapy. In addition to the assessment of clinical symptoms, signs of thrombosis, diagnoses established with imaging techniques and of laboratory parameters, early complications and obstetric data obtained in surgically and conservatively treated patients were compared. RESULTS: The incidence of deep vein thrombosis in the 26 patients (median age 28 years) was 0.21%. In 53.8% of the cases the occurrence of thrombosis was observed in the second trimester (median: 27.5 weeks of gestation). The presence of risk factors was demonstrated in 58% of cases. The most frequently reported symptoms were swelling of the affected leg (88.5%) and pain (61.5%). A marked predilection for the left leg was recorded in 88% of cases. In contrast to phlebography, twice the number of sonographic studies were performed. The comparison of both therapeutic regimes showed a three-fold increase in the rate of early complications in patients after thrombectomy. The rate of recurrent thrombosis in these patients was 58.3% compared to a recurrence rate of 15.4% in patients undergoing heparin therapy. CONCLUSIONS: Recurrent thrombosis and pulmonary embolism represent the most frequent complications associated with thrombosis in the deep venous system during pregnancy. Although currently there is a lack of conclusive data on the development of postthrombotic syndrome, heparin therapy appears to be associated with fewer maternal risks. Interdisciplinary cooperation is urgently needed.

Determination of pyrrolidinone in plasma by high-performance liquid chromatography.

A sensitive and selective high-performance liquid chromatographic method for the determination of pyrrolidinone (I) in plasma is described. Compound I was extracted from plasma with methylene chloride using kieselguhr as aqueous phase support. The gamma-aminobutyric acid (II) formed after alkaline hydrolysis of I was derivatised with o-phthalaldehyde, chromatographed on a reversed-phase column, and quantified by fluorescence detection. The limit of quantification was 2.5 ng/ml (intra-assay R.S.D. 5%) using a 1-ml plasma sample. The inter-assay precision was 3-14% (R.S.D.) over the concentration range 2000-5 ng/ml, and the recovery from plasma was quantitative (99.3 +/- 2.9%). The accuracy of this method was established from the good agreement between the values obtained after the analysis of plasma samples by both this method and a gas chromatography--mass spectrometry method. The high-performance liquid chromatographic procedure was applied to the determination of (a) endogenous I in human plasma samples and (b) I in plasma following intravenous administration of this substance to a dog. In twelve human subjects, endogenous concentrations of I of 8.3 +/- 2.3 ng/ml (gas chromatography--mass spectrometry method: 6.1 +/- 2.6 ng/ml) were found.

2-Pyrrolidinone and succinimide endogenously present in several mammalian species.

2-Pyrrolidinone and succinimide were identified in blood plasma of man, rat, and mouse. Dog plasma contained only traces of 2-pyrrolidinone not exceeding significantly the detection limit of our GCMS-method. Succinimide but not 2-pyrrolidinone could also be found in the brains of rat and mouse. Evidence is presented for a metabolic pathway leading from 2-pyrrolidinone to succinimide, with 5-hydroxy-2-pyrrolidinone as an intermediate.

Single-dose pharmacokinetics of the MAO-inhibitor moclobemide in man.

The single-dose kinetics of the MAO-inhibitor p-chloro-N-(2-morpholinoethyl)-benzamide (moclobemide, Ro 11-1163) following oral and i.v. administration to six healthy subjects is described. The dosage was 50 mg throughout (1 tablet moclobemide orally, 2.0 ml ampoule moclobemide i.v.). The unchanged drug in plasma was measured by means of an HPLC-assay. The i.v. plasma level curves were analyzed assuming a two-compartment model. The drug was rapidly distributed into the tissue compartment and was then eliminated from the body with a mean half-life t 1/2 beta of about 1 h (range 0.79-1.34 h). The volume of distribution Vss was of medium size (range 0.81-1.25 l/kg). The oral bioavailability was reduced in consequence of the effect of the first passage through the liver and amounted to 44% on average (range 27-70%). As to the drug absorption from the intestinal tract the extent and rate of this process were shown to be large (more than 95% absorbed on average, tmax-values within 1 h).