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61.
H. Kellner W. G. Zoller K. Jacob H. S. Füeßl 《Journal of molecular medicine (Berlin, Germany)》1988,66(19):953-956
Summary Urinary and fecal total, isomer I, and isomer III coproporphyrin excretion of a Rotor's syndrome patient and his family were determined. The proprositus showed increased urinary total coproporphyrin excretion (248 µg/24 h) and a shift of the coproporphyrin isomer I/III relation (70%/30%). The propositus's father and two siblings also had elevated renal excretion of coproporphyrin I. Total coproporphyrin excretion was enhanced only in the propositus's father and one sibling, while being normal in another sibling. All family members that could be investigated showed considerably decreased fecal porphyrin excretion. In Rotor's syndrome porphyrin excretion is mainly renal. The coproporphyrin isomer I/III relation is shifted towards isomer I. Phenotypically normal relatives with normal bilirubin plasma levels may have alterations in both their renal and enteral coproporphyrin excretion.
Herrn Professor Dr. med. N. Zöllner zum 65. Geburtstag gewidmet 相似文献
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63.
Heike CL Cunningham ML Steiner RD Wenkert D Hornung RL Gruss JS Gannon FH McAlister WH Mumm S Whyte MP 《American journal of medical genetics. Part A》2005,(2):67-77
Epidermal nevus syndrome (ENS) is a rare, sporadic, congenital disorder of unknown etiology featuring a complex and highly variable phenotype that can include focal or generalized skeletal disease. We describe a young man with ENS manifesting right-sided linear skin lesions, generalized weakness, diffuse osteopenia associated with hypophosphatemic rickets, and distinctive focal bone lesions ipsilateral to the skin findings. Review of the literature concerning ENS-associated skeletal disease suggested such focal bone defects are fibrous dysplasia, but our patient did not have the typical radiographic or histopathologic findings of fibrous dysplasia. Nevertheless, his circulating fibroblast growth factor 23 (FGF-23) level was elevated, likely functioning as a "phosphatonin," yet no activating mutations in GNAS previously reported in fibrous dysplasia or McCune-Albright syndrome were detected in his leukocytes or affected skin. We postulate that the focal skeletal disease, although different than fibrous dysplasia, may be a source of FGF-23 in ENS. 相似文献
64.
Lichtenberg A Dumlu G Walles T Maringka M Ringes-Lichtenberg S Ruhparwar A Mertsching H Haverich A 《Biomaterials》2005,26(5):555-562
Investigation of cell abilities to growth, proliferation and (de)-differentiation in a three-dimensional distribution is an important issue in biotechnological research. Here, we report the development of a new bioreactor for three-dimensional cell culture, which allows for co-cultivation of various cell types with different culture conditions in spatial separation. Preliminary results of neonatal rat cardiomyocyte cultivation are shown. Isolated neonatal rat cardiomyocytes were cultured in spatial separated bioreactor compartments in recirculating medium on a biodegradable fibrin matrix for 2 weeks. Glucose, lactate, and lactate dehydrogenase (LDH), pO2, pCO2, and pH levels were monitored in the recirculated medium, daily. Morphological characterization of matrix and cells was assessed by hematoxylin and eosin staining, and MF-20 co-immunostaining with 4',6-diamidino-2-phenylindole (DAPI). Cell viability was determined by LIVE/DEAD staining before cultivation and on day 3, 7, and 14. The optimized seeding density in the matrix was 2.0 x 10(7) cells retaining cellular proportions over the cell culture period. The bioreactor allows the maintenance of physiologic culture conditions with aerobic cell metabolism (low release of lactate, LDH), a high oxygen tension (pO2-183.7 +/- 18.4 mmHg) and physiological pH values (7.4 +/- 0.02) and a constant level of pCO2 (43.1 +/- 2.9) throughout the experimental course. The cell viability was sufficient after 2 weeks with 82 +/- 6.7% living cells. No significant differences were found between spatial separated bioreactor compartments. Our novel multifunctional bioreactor allows for a three-dimensional culture of cells with spatial separation of the co-cultured cell groups. In preliminary experiments, it provided favorable conditions for the three-dimensional cultivation of cardiomyocytes. 相似文献
65.
Dysfunction of axonemal dynein heavy chain Mdnah5 inhibits ependymal flow and reveals a novel mechanism for hydrocephalus formation 总被引:8,自引:0,他引:8
Ibañez-Tallon I Pagenstecher A Fliegauf M Olbrich H Kispert A Ketelsen UP North A Heintz N Omran H 《Human molecular genetics》2004,13(18):2133-2141
Motility of unicellular organisms occurred early in evolution with the emergence of cilia and flagella. In vertebrates, motile cilia are required for numerous functions such as clearance of the airways and determination of left-right body asymmetry. Ependymal cells lining the brain ventricles also carry motile cilia, but their biological function has remained obscure. Here, we show that ependymal cilia generate a laminar flow of cerebrospinal fluid through the cerebral aqueduct, which we term as 'ependymal flow'. The axonemal dynein heavy chain gene Mdnah5 is specifically expressed in ependymal cells, and is essential for ultrastructural and functional integrity of ependymal cilia. In Mdnah5-mutant mice, lack of ependymal flow causes closure of the aqueduct and subsequent formation of triventricular hydrocephalus during early postnatal brain development. The higher incidence of aqueduct stenosis and hydrocephalus formation in patients with ciliary defects proves the relevance of this novel mechanism in humans. 相似文献
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68.
Egger G Burda A Obernosterer A Mitterhammer H Kager G Jürgens G Hofer HP Fabjan JS Pilger E 《Inflammation》2001,25(2):129-135
The aim of the study was to demonstrate an activation of polymorpho-nuclear leukocytes (PMNs) in chronic progressive atherosclerosis (ATH). A group of patients with ATH, and a group of ATH patients under aspirin (ASA) therapy were compared with control persons without atherosclerotic alterations (healthy controls). Each group comprised 15 male age-matched subjects. The following inflammatory parameters related to PMN activities were measured: the polymorphonuclear leukocyte (PMN) blood count; blood PMN migration and reactive oxygen species release in vitro; the blood levels of PMN elastase, malondialdehyde, antibodies to oxidized LDL and soluble ICAM-1. In ATH patients, the PMN blood counts and the share of blood PMNs migrating upon platelet activating factor and leukotriene B4 stimulation were significnatly above the values of the healthy controls, while the other parameters were not significantly altered. ASA treatment attenuated the inflammatory response and reduced the differences between ATH and the healthy controls. It can be concluded that, in patients with chronic progressive atherosclerosis, PMNs are involved in the inflammatory process underlying the disease. 相似文献
69.
Heike Nave Susanne Kuhlmann Georg Brabant Reinhard Pabst 《Experimental and toxicologic pathology》2003,55(1):45-49
Leptin, a potent anorectic, 16-kDa, adipose tissue-derived protein, predominantly acts in hypothalamic nuclei, signaling obesity and modulating ingestive behavior. To reach this brain area, leptin, probably has to cross the blood-brain barrier (BBB). In some cases of obesity, enhanced leptin levels in the blood do not result in anorectic effects, probably due to an altered leptin transport across the BBB. Therefore, we investigated the BBB in lean and diet-induced obese Lewis rats. To obtain information about the presence of microvessels with barrier dysfunction we examined three brain areas (hypothalamus, cortex, hippocampus) using a monoclonal antibody which detects intact microvessels of the BBB (anti-endothelial barrier antigen, anti-EBA). The results showed a significantly reduced EBA staining in the brain sections of the obese animals, except the hippocampus, compared to the control group. In a second step we injected I125-labeled leptin intravenously (i.v.) in permanent i.v.-cannulated, unrestrained Lewis rats (lean and obese). We measured the radioactivity in the cerebrospinal fluid after puncture of the cisterna magna, in the blood and brain tissue 90 min after injection. The leptin content in the cerebrospinal fluid and brain was not reduced in obese compared to lean rats, thus showing a similar transport capacity of the BBB in both experimental groups. Therefore, the results of the in vivo investigations do not indicate an impairment of the BBB in diet-induced obesity, despite the immunohistological findings. Further functional and morphological studies are necessary to evaluate the specific role of other organs and distinct forms of leptin (free and protein-bound) in the pathogenesis of diet-induced obesity. 相似文献
70.
Steffen Maiwald Helga Weißenborn Heike Windisch Christian Sommer Gert Müller Rudolf Taube 《Macromolecular chemistry and physics.》1997,198(10):3305-3315
The activation of the tris(allyl)neodymium complex Nd(η3-C3H5)3 · dioxane with alkylaluminoxanes (MAO or HIBAO) results in highly selective catalysts for the 1,4-cis-polymerization of butadiene (cis-selectivity up to 80%). Under standard conditions (50°C, toluene), the turnover frequency (TOF) of the catalyst/MAO system amounts to 10–15000 mol butadiene/(mol Nd · h). Molecular weight determinations indicate the formation of only one polymer chain per neodymium center as in a living polymerization reaction, and for the catalyst/HIBAO system the rate law rp = kp [Nd][C4H6] with kp = 8,7 · 10?2 mol/(L · s) (at 25°C) has been derived. As the catalytically active species, a cationic monobutenyl neodymium(III) complex is discussed, which is stabilized through coordinative interaction with the counter anion as well as the growing polybutadiene chain. This cationic complex reacts under insertion with butadiene in a bimolecular fashion. 相似文献