Biomedical subjects

U Hübner

Publications and source records attributed to U Hübner.

At least 19 recordsLinked to original sources

PubMed2006

Structure and in vitro cytocompatibility of the gastropod shell of Helix pomatia.

Distinguishing features of biological constructions are high stability and adaptation to their environment. Beside biocompatibility, nontoxicity and degradability these characteristics are demanded for new biomaterials in the field of tissue engineering. This study investigated the chemical composition, the organization and the in vitro osteoconductive potential of the terrestrial gastropod shell (Helix pomatia) on CAL72 and human osteoblast-like cells. Chemical composition of the biomaterial was examined by X-ray diffraction (XRD) and scanning electron microscopy (SEM) was performed to analyze the architecture of the snail shell and the morphology of the seeded cells. A double staining procedure (FDA/PI) and a proliferation test (EZ4U) assessed the viability of the cells. Microscopical images showed the multilayered architecture of the aragonite shell with hexagonal crystals on the inner side. The cells spread well on the biomaterial and the highest proliferation rate could be measured with CAL72 cells on the inner shell surface. The osteoconductive effects of this natural biomaterial could encourage further experiments in the field of tissue engineering.

Animals↗

PubMed2006

Four-qubit device with mixed couplings.

We present the first experimental results on a device with more than two superconducting qubits. The circuit consists of four three-junction flux qubits, with simultaneous ferro- and antiferromagnetic coupling implemented using shared Josephson junctions. Its response, which is dominated by the ground state, is characterized using low-frequency impedance measurement with a superconducting tank circuit coupled to the qubits. The results are found to be in excellent agreement with the quantum-mechanical predictions.

Journal Article↗

PubMed2005

Search for ideal biomaterials to cultivate human osteoblast-like cells for reconstructive surgery.

In this study we cultured human osteoblast-like cells on 16 different biomaterials to find an optimal biomaterial for subsequent use in reconstructive surgery. The tested biomaterials can be divided into five groups: collagen-based membranes of bovine, equine or calf origin, tricalcium phosphate based membranes (alpha and beta), hyaluronic acid based, anorganic bovine bone and anorganic silicone-based membranes. Cell proliferation and cell colonization (Environmental Scanning Electron Microscope, ESEM) analysis were performed. The results of the study demonstrated that four of the examined biomaterial/cell constructs showed a very good proliferation rate and cell density: No. 3 (Tissue Vlies), No. 7 (Sepra film), No. 16 (Biobrane) and No. 17 (Biomend). No favourable group of biomaterials was noticeable. Moreover, the results indicate that these four biomaterials as a part of bone constructs are the best tools for engineering new bone tissue. In contrast, biomaterials No. 19a (Bio-Oss) and 19b (Bio-Oss Collagen) showed the lowest proliferation rates. The result of No. 19b was improved by treatment in the perfusion chamber for 48 h as well as by additional use of vacuum. The present study is an important base for further analysis of biomaterials and consequently for the development of tissue engineering.

Bioartificial Organs↗

PubMed2005

Current and future use of ICT for patient care and management in German acute hospitals--a comparison of the nursing and the hospital managers' perspectives.

OBJECTIVES: This study aimed at gaining comprehensive information on the current status of patient care and management applications used in German acute hospitals. Since the degree of ICT coverage in hospitals depends on the attitude of the key decision makers we also wanted to capture their plans and priorities and herewith try to predict future use. METHODS: We therefore conducted a nation-wide survey including all acute hospitals in Germany in which two questionnaires were mailed to each hospital, one to the nursing managers, the other to the hospital managers. RESULTS: Six hundred hospitals participated in the survey which corresponds to an overall response rate of 27.6%. Accounting (84%) was found to be the most prevalent management module. Rostering was implemented in every second hospital. For clinical applications laboratory systems ranked first (69%). Ordering systems were used in nearly every second hospital. Nineteen percent of the hospitals reported employing an electronic patient record, 7% a nursing documentation system. Ranked by their priorities ordering systems hold the first position and care planning the last position. According to their plans, hospital managers, not nursing managers, intend to introduce nursing documentation. In contrast, nursing managers favor ordering and rostering for the near future. CONCLUSIONS: There is still a preponderance of management-oriented systems in German hospitals, yet clinical applications, in particular those supporting communications, will gain ground. The future of documentation systems is unclear, unless they not only provide statistical data for the management but support the clinical process properly.

Attitude of Health Personnel↗

PubMed2004

Homocysteine in relation to C-reactive protein and low-density lipoprotein cholesterol in assessment of cardiovascular risk.

Coronary vascular disease (CVD) is a chronic, multifactorial disease that occurs often in individuals without known risk factors. We investigated the predictive value of homocysteine (Hcy) in relation to C-reactive protein (CRP) and low-density lipoprotein (LDL)-cholesterol in patients with confirmed coronary disease. The study included 87 German and 92 Syrian patients in addition to 87 German and 64 Syrian control individuals. Patients and controls were of comparable age, lifestyles and cultural background. Patients of both ethnic groups had significantly higher concentrations of Hcy and C-reactive protein compared to the controls. The lipids were higher only in Syrian patients compared to the controls. Elevated concentrations of Hcy or that of CRP (>75th percentiles) were associated with increased probability for CVD. In both population groups, the risk increased markedly in subjects who had elevated concentrations of Hcy and CRP or those who had elevated concentrations of Hcy and LDL-cholesterol. The results emphasize that detemination of Hcy may improve the predictive value of C-reactive protein and the LDL-cholesterol. Measurements of these markers are especially important for identification of patients at high risk for CVD.

Adult↗

PubMed2003

Influence of donor age and culture conditions on tissue engineering of mucosa autografts.

In oral surgery the transplantation of tissue engineered mucosa is used more frequently. The conventional single cell suspension culture method (SCSM) involves murine feeder cells and foetal calf serum. The explant technique (ET) has been used as alternative culture procedure. Aim was to study the efficacy of the ET and the SCSM without feeder cells to grow primary cultures and to test the effects of donor age, of extracellular matrix proteins (ECMP), and of autogenous serum on cell growth in explant cultures. These factors were assessed in cultures of 58 patients overall. In 48 cultures of 12 patients primary cell growth was compared between the ET and the SCSM. Eighteen of 24 cultures were established with the ET whereas only 3 of 24 were established with the SCSM. To test the influence of donor age on cell multiplication, the proliferation rate (DNA synthesis measured by bromodeoxyuridine uptake) and the overall growth (DNA content) was determined in cultures of five young and five old donors. In cultures from old donors (mean age 56 years) proliferation was lower but more sustained relative to the cultures from the young donors (mean age 25 years). In old donors overall in vitro cell growth was only 2/3 of that in young donors. In cultures of 20 donors the influence on cell adhesion and growth of the ECMP fibronectin and laminin was assessed by planimetry. While ECMP augmented explant adhesion, these substances did not enhance keratinocyte growth significantly. Comparing the influence of autogenous and foetal calf serum on cell growth no differences were observed in all cultures of the six donors. In conclusion, the ET without additional ECMP coating and with autogenous instead of foetal calf serum are now used to culture gingival keratinocytes for tissue engineering mucosa grafts. Consequently xenogenous components are avoided, being a considerable advantage.

Adolescent↗

PubMed2002

Four cases of desmosis coli: severe chronic constipation, massive dilatation of the colon, and hypoperistalsis due to of changes in the colonic connective-tissue net.

We present four patients 5, 10, 12, and 17 years of age, each with a long history of severe constipation and hypoperistalsis of the gut. Three had partial or total resection of the colon, all had enterostomies, and only one maintains normal bowel function after reanastomosis. We report the clinical courses, radiologic findings, and operative procedures for all four cases. Preoperative full-thickness biopsies and the resected colon specimens revealed a complete or incomplete lack of the mesh network of collagen. The connective-tissue layer between the circular and longitudinal muscles was missing. Contrary to expectations, the enteric nervous system (ENS) was normal or near-normal in the affected areas. Hypo- and dysganglionosis was found additionally in some proximal segments of colon and/or small bowel. This combination of clinical symptoms and pathological findings is called desmosis of the colon with reference to a working hypothesis in a preliminary report by Meier-Ruge in 1998. Aplastic or hypoplastic desmosis may be the reason for the disturbed gut motility. Histologic examination should thus not only exclude changes of the ENS.

Adolescent↗

PubMed2002

How to optimize seeding and culturing of human osteoblast-like cells on various biomaterials.

The optimization of seeding and culturing of human osteoblast-like cells on three collagen-based biomaterials (bovine, equine and calf collagen membrane) was studied by cell proliferation and cell colonization (scanning electron microscopy) analysis. Osteoblasts of five patients were seeded onto the three biomaterials and two different parameters were varied: the time intervals between initial seeding and adding culture medium (2 h 6 h. 12 h, 24 h) and the seeding concentration (1 x 10(5), 1 x 10(6), 2 x 10(6)cells/ml) of cells onto biomaterials. The results of the study demonstrated that the time interval between seeding osteoblasts and adding culture medium as well as the seeding concentration effects the cell proliferation and the cell colonization. The best proliferation rate was achieved by adding the culture medium 2 h after initial seeding and with a seeding density of 1 x 10(5) cells/ml. Moreover, all three biomaterials resulted in different proliferation rates. The best proliferation rate resulted with the bovine collagen membrane. In conclusion, the examined parameters are very important for the development of the tissue engineering techniques and in a larger perspective also for reconstructive surgery.

Alkaline Phosphatase↗

PubMed2001

The titanium surface texture effects adherence and growth of human gingival keratinocytes and human maxillar osteoblast-like cells in vitro.

The adhesion, orientation and proliferation of human gingival epithelial cells and human maxillar osteoblast-like cells in primary and secondary culture were studied on glossy polished, sandblasted and plasma-sprayed titanium surfaces by scanning electron microscopy and in thin sections. The primary cultured explants of human gingival epithelial cells attached, spread and proliferated on all titanium surfaces with the greatest extension on the polished and the smallest extension on plasma-sprayed surfaces. In secondary suspension cultures of gingival keratinocytes, attachment spreading and growth was only observed on polished and plasma-sprayed surfaces, but not on sandblasted surfaces. Moreover, the attachment of these cells depended on the seeding concentration as well as on the coating with fetal calf serum. Cells on polished surfaces developed an extremely flat cell shape, but on sandblasted and plasma-sprayed surfaces a more cuboidal shape. In contrast human maxillar osteoblasts seeded as secondary suspension cultures attached very well to all three differently textured titanium surfaces and showed identical growth patterns independent of the titanium surface structure. These findings suggest that cell morphology, orientation, proliferation and adhesion of human gingival epithelial cells in primary or secondary culture are dependent on the texture of the titanium surface whereas no such differences were observed for maxillar osteoblast-like cells. In conclusion, the soft tissue integration and response is more influenced by the surface texture than the process of osseointegration.

Alkaline Phosphatase↗

PubMed2001

Immunohistochemical study during healing of free palatal mucosa grafts on plastic-embedded samples.

This immunohistochemical study describes changes in the histology and in the distribution of the basement membrane components laminin and collagen IV as well as of the cytokeratins (CK)1/2/10/11, CK5/6, CK13, CK14, CK17, CK19 during the take of free split mucosa (epithelial and connective tissue) transplants in humans up to 36 months post-operative. Histology showed a flattening of the epithelial layer within the first 2 weeks after grafting, followed initially by an increase (25-30 layers, week 6) and later on by a decrease of cell layers in the epithelium (15-20 layers, week 20). From that time onwards, clear stratification and reteridges as signs of differentiation were present. Up to day 14 of graft take, the linear staining patterns for laminin and collagen IV were interrupted, which was not observed at any later stage. During this early interval CK5/6, CK1/2/10/11, CK14 and CK17 were expressed in all epithelial layers. The reactions for CK5/6 and CK1/2/10/11 were less intensive. At 6 weeks, CK1/2/10/11 stained the intermediate and superficial layers, being consistent with findings after longer graft take. CK5/6 reacted in the basal and intermediate cell layers, and CK13, CK14 and CK17 reacted in all layers. In the following period up to week 20, CK5/6 were found in the parabasal cells of the intermediate cell layers and the basal cells. CK14 staining was confined to these cell layers too, but also showed some reaction in the superficial layers. CK13 and CK17 were still bound to all layers. At 7 months post-operative, CK5/6 and CK14 were seen in their typical localisation in the basal cell layer and the parabasal cells of the intermediate layers, CK17 was seen mainly in the intermediate layer and CK13 was seen in focal areas of all layers. Anti-CK19 reacted only with single basal and parabasal cells up to week 20. These results suggest that during healing of mucosal autografts there is a sequence of changes in the expression of cell biological differentiation markers that may involve an epithelio-connective tissue interaction before the typical patterns for the donor side were observed again on the gingiva or mucosa of the hard palate.

Adult↗

PubMed2001

Genetic defects as important factors for moderate hyperhomocysteinemia.

The genes for the enzymes methylenetetrahydrofolate reductase (MTHFR), methionine synthase (MS), methionine synthase reductase (MSR) and cytathionine-beta-synthase (CBS) play an important role in homocysteine metabolism. Rare mutations in these genes cause severe hyperhomocysteinemia and clinical symptoms. Growing interest has focused on common mutations with moderate effects on homocysteine levels. We studied 280 subjects of different age groups for the following mutations: MTHFR677C-->T and 1298A-->C, MS2756A-->G, MSR66A-->G and the 68 bp insertion in the CBS gene. The median value for homocysteine increased significantly with age (median homocysteine levels: 7.5, 12.4 and 16.5 micromol/l in the age groups 20-43, 65-75 and 85-96 years, respectively). The genotypes of the MTHFR677C-->T mutation were associated with differences in plasma homocysteine levels, but without reaching significance. Individuals homozygous for the MTHFR677C-->T mutation had a 2.3 micromol/l higher median homocysteine level compared to individuals with the wild-type allele. This effect was pronounced in combination with low folate levels and abolished with higher folate in plasma. For the other three mutations no association with homocysteine values could be determined. The analysis of homocysteine metabolite cystathionine by backward regression analysis revealed a significant correlation of the MS2756A-->G mutation with cystathionine level. This increase could indicate a disturbed remethylation. In summary, larger and homogeneous study populations are necessary to quantify the small effects of common mutations on homocysteine levels. This may also be the reason that no effects of genetic interactions between two genotypes were observed.

5-Methyltetrahydrofolate-Homocysteine S-Methyltran↗

PubMed2001

Continuous monitoring of regional cerebral blood flow during temporary arterial occlusion in aneurysm surgery.

OBJECT: Temporary arterial occlusion (TAO) during aneurysm surgery carries the risk of ischemic sequelae. Because monitoring of regional cerebral blood flow (rCBF) may limit neurological damage, the authors evaluated a novel thermal diffusion (TD) microprobe for use in the continuous and quantitative assessment of rCBF during TAO. METHODS: Following subcortical implantation of the device at a depth of 20 mm in the middle cerebral artery or anterior cerebral artery territory, rCBF was continuously monitored by TD microprobe (TD-rCBF) throughout surgery in 20 patients harboring anterior circulation aneurysms; 46 occlusive episodes were recorded. Postoperative radiographic evidence of new infarction was used as the threshold for failure of occlusion tolerance. The mean subcortical TD-rCBF decreased from 27.8+/-8.4 ml/100 g/min at baseline to 13.7+/-11.1 ml/100 g/min (p < 0.0001) during TAO. The TD microprobe showed an immediate exponential decline of TD-rCBF on clip placement. On average, 50% of the total decrease was reached after 12 seconds, thus rapidly indicating the severity of hypoperfusion. Following clip removal, TD-rCBF returned to baseline levels after an average interval of 32 seconds, and subsequently demonstrated a transient hyperperfusion to 41.4+/-18.3 ml/l 00 g/min (p < 0.001). The occurrence of postoperative infarction (15%) and the extent of postischemic hyperperfusion correlated with the depth of occlusion-induced ischemia. CONCLUSIONS: The new TD microprobe provides a sensitive, continuous, and real-time assessment of intraoperative rCBF during TAO. Occlusion-induced ischemia is reliably detected within the 1st minute after clip application. In the future, this may enable the surgeon to alter the surgical strategy early after TAO to prevent ischemic brain injury.

Adult↗

PubMed2000

Long-term results of treatment of single-system ectopic ureters.

Single-system ureteral ectopia (UE) encompasses a spectrum of malformations involving the bladder trigone, ureter, and kidney. The clinical presentation is variable, and both diagnostic and therapeutic problems are common. Reduced renal function in these patients may result from primary dysplasia, obstruction, vesicoureteral reflux, or recurrent infection. Based on our experience of seven patients, suggestions for diagnostic procedures and criteria for renal saving versus nephrectomy are offered. The relationship between ostium localization, renal function, and long-term results was investigated. From 1972 to 1990, five female and two male patients were studied. During the same period, 31 patients with UE and duplex kidneys were seen. Ages ranged from 1 day to 7 years. A ureteric opening into the bladder neck was associated with dilatation of the ureter and renal pelvis. Two patients had vaginal ectopia and severe renal dysplasia. In one, a cyst of the vaginal wall (Gardner's cyst) was detected at birth. A male newborn had multicystic renal dysplasia on the left and ureteric ectopia to the ductus deferens on the right side. To our knowledge, he is the first patient reported with renal function totally dependent on a kidney with severe UE. Follow-up ranged from 4 to 9 years. One patient died in the postoperative period because of renal failure and sepsis. All the others are well and have normal creatinine values. Improvement of renal function was noted after ureteral reimplantation (URI) in patients with bladder-neck ectopia. The numbers of infections were also drastically reduced. Our observations suggest that the combination of ultrasound, cyst urethrography, and cystoscopy will be diagnostic in most patients. A suspicion of UE should be raised in symptomatic patients with apparently solitary kidneys, enuresis ureterica, or atypical obstructive uropathy. Reduced renal function in some patients with ectopia to the bladder neck will improve after URI. This may be of importance in patients with bilateral anomalies and marginal renal function.

Cause of Death↗

PubMed2000

CyA and OxLDL cause endothelial dysfunction in isolated arteries through endothelin-mediated stimulation of O(2)(-) formation.

BACKGROUND: Cyclosporin A (CyA) and oxidized low-density lipoprotein (OxLDL) cause endothelial dysfunction, partly through stimulation of O(2)(-) formation (which can inactivate nitric oxide). We investigated whether CyA and OxLDL potentiate their influence on oxidative stress, whether endothelin (ET) is a mediator of CyA- and OxLDL-induced O(2)(-) formation, and whether enhanced oxidative stress results in further attenuation of endothelium-dependent vasodilation. METHODS AND RESULTS: Human LDL was oxidized by Cu(++). O(2)(-) formation of isolated rat aortic rings was measured using a chemiluminescence assay. Incubation (60 min) of aortic rings with CyA (10 ng-10 microg/ml) or with OxLDL (300 microg/ml) caused a significant, dosedependent increase of the basal O(2)(-) formation. Pretreatment of the aortic rings with CyA (10 ng/ml) further enhanced the OxLDL-induced O(2)(-) formation by factor 1.9. The enhancement of the OxLDL-induced stimulation of O(2)(-) formation by CyA could be completely blocked by BQ123, a selective endothelin-1 (ET-1) receptor antagonist. Likewise, exogenously applied ET-1 (1 nM) potentiated the OxLDL-induced O(2)(-) formation by factor 1.8. Endothelium-dependent dilation was measured in isolated rings of rabbit aorta superfused with physiological salt solution in an organ bath. Incubation of the aortic rings with CyA (10 microg/ml, 60 min) or with OxLDL (300 microg/ml, 60 min) alone did not attenuate endothelium-dependent dilations. However, coincubation of the aortic rings with CyA+OxLDL in the presence of diethyl-dithio-carbamate, an inhibitor of the endogenous superoxide dismutase, caused a 60% inhibition of acetylcholine-induced dilator responses. CONCLUSIONS: Coincubation of isolated aortic rings with CyA and OxLDL causes a potent enhancement of vascular O(2)(-) formation. ET-1 seems to be mediator of the CyA-induced O(2)(-) formation. Enhanced oxidative stress results in further attenuation of endothelium dependent vasodilation.

Animals↗

PubMed2000

Ultrasound in the diagnosis of fractures in children.

We compared the results of primary ultrasonographic examination of 163 children with 224 suspected fractures with the subsequent radiological findings. The aim was to assess the value of ultrasound in the diagnosis of fractures in children. We found a good correlation for fractures of the long bones of the upper and lower limbs. Ultrasound was most reliable for the detection of simple femoral and humeral diaphyseal fractures and fractures of the forearm. It was less dependable for compound injuries and fractures adjacent to joints, lesions of the small bones of the hand and foot, non-displaced epiphyseal fractures (Salter-Harris type 1) or those with a fracture line of less than 1mm. We were able to distinguish several types of fracture in which the use of ultrasound alone gave reliable information and further radiography was unnecessary. We discuss the advantages and disadvantages of skeletal ultrasonographic studies in children.

Adolescent↗

PubMed2000

Building a Web-based drug ordering system for hospitals: from requirements engineering to prototyping.

Web-based drug ordering allows a growing number of hospitals without pharmacy to communicate seamlessly with their external pharmacy. Business process analysis and object oriented modelling performed together with the users at a pilot hospital resulted in a comprehensive picture of the user and business requirements for electronic drug ordering. The user requirements were further validated with the help of a software prototype. In order to capture the needs of a large number of users CAP10, a new method making use of pre-built models, is proposed. Solutions for coping with the technical requirements (interfacing the business software at the pharmacy) and with the legal requirements (signing the orders) are presented.

Computer Simulation↗

PubMed1999

Effects of the soluble guanylyl cyclase activator, YC-1, on vascular tone, cyclic GMP levels and phosphodiesterase activity.

The vasomotor and cyclic GMP-elevating activity of YC-1, a novel NO-independent activator of soluble guanylyl cyclase (sGC), was studied in isolated rabbit aortic rings and compared to that of the NO donor compounds sodium nitroprusside (SNP) and NOC 18. Similarly to SNP and NOC 18, YC-1 (0.3-300 microM) caused a concentration-dependent, endothelium-independent relaxation that was greatly reduced by the sGC inhibitor 1-H-[1,2,4]oxadiazole[4,3-a]quinoxalin-1-one (ODQ 10 microM; 59% inhibition of dilation induced by 100 microM YC-1) suggesting the activation of sGC as one mechanism of action. Preincubation with YC-1 (3 and 30 microM) significantly increased the maximal dilator responses mediated by endogenous NO in aortic rings that was released upon exposure to acetylcholine, and enhanced the dilator response to the exogenous NO-donors, SNP and NOC 18, by almost two orders of magnitude. Vasoactivity induced by SNP and YC-1 displayed different kinetics as evidenced by a longlasting inhibition by YC-1 (300 microM) on the phenylephrine (PE)-induced contractile response, which was not fully reversible even after extensive washout (150 min) of YC-1, and was accompanied by a long-lasting elevation of intracellular cyclic GMP content. In contrast, SNP (30 microM) had no effect on the vasoconstrictor potency of PE, and increases in intravascular cyclic GMP levels were readily reversed after washout of this NO donor compound. Surprisingly, YC-1 not only activated sGC, but also affected cyclic GMP metabolism, as it inhibited both cyclic GMP break down in aortic extracts and the activity of phosphodiesterase isoforms 1-5 in vitro. In conclusion, YC-1 caused persistent elevation of intravascular cyclic GMP levels in vivo by activating sGC and inhibiting cyclic GMP break down. Thus, YC-1 is a highly effective vasodilator compound with a prolonged duration of action, and mechanisms that are unprecedented for any previously known sGC activator.

Animals↗

PubMed1997

Glycosylation variants of human TSH selectively activate signal transduction pathways.

The oligosaccharide chains of pituitary glycoprotein hormones such as human thyroid-stimulating hormone (hTSH) have been shown to be important in biosynthesis, subunit association, secretion and bioactivity. However, the exact biological significance of these glycosylation variants (isoforms) remains controversial. The aim of this paper is to investigate the role of hTSH glycosylation variants in signal transduction. Human pituitary standard TSH (2nd International Reference Preparation 80/558; IRP-hTSH) was treated with neuraminidase, fractionated by isoelectric focusing (IEF) and affinity chromatography using the lectins concanavalin A (Con A) and lentil. To determine the in vitro bioactivity of these hTSH isoforms, simultaneous measurement of cAMP formation and inositol phosphates release was applied in two different cell systems (CHO cells stably and Cos-7 cells transiently transfected with hTSHR cDNA). Desialylated TSH variants showed a significantly increased ratio of bioactivity to immunoreactivity for cAMP production in CHO-R cells (B/I ratio desialylated variants: 3.54 +/- 0.005; B/I ratio sialylated variants: 2.84 +/- 0.01 P < 0.05). Testing the bioactivity of hTSH glycosylation variants isolated by IEF, we found basic variants to be significantly more active than acidic ones in stimulating the cAMP formation in CHO-R cells (B/I ratio basic variants: 9.92 +/- 0.64; neutral variants: 5.98 +/- 0.07; acidic variants: 2.80 +/- 0.12; P < 0.01). There were no differences in stimulation of IP-release. High-mannose TSH variants (firmly bound to Con A) showed greater potency to stimulate cAMP formation and IP-release in both CHO-R and Cos-7 cells than biantennary TSH variants (weakly bound to Con A). Both core-fucosylated (lentil-bound) and core-unfucosylated (lentil-unbound) TSH variants proved to be strong stimulators of cAMP release in CHO and Cos-7 cells. In CHO-R (Cos-7) cells, 400 microU/ml core-fucosylated TSH stimulated cAMP formation 14(2.6)-fold, core-unfucosylated TSH 7.3(2.3)-fold over control values. In contrast to our findings of cAMP activation by both core-fucosylated and core-unfucosylated TSH variants, release of IPs was stimulated only by, core-fucosylated (lentil-bound) TSH variants and not by TSH variants lacking core-fucose residues (lentil-unbound TSH). This was true for both CHO-R and Cos-7 cells. The lentil-unbound TSH therefore showed an identical differential activation of signal transduction pathways in two different cell systems: strong stimulation of the cAMP-cascade without activation of IPs release (P < 0.05). In conclusion, we showed for the first time for TSH that the two dominant intracellular signal transduction systems (cAMP formation and IPs release) are activated to different degrees by hTSH glycosylation variants.

Animals↗