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Bereswill S, Greiner S, van Vliet AH, Waidner B, Fassbinder F, Schiltz E, Kusters JG, Kist M. Regulation of ferritin-mediated cytoplasmic iron storage by the ferric uptake regulator homolog (Fur) of Helicobacter pylori. J Bacteriol 2000; 182:5948-53. [PMID: 11029412 PMCID: PMC94726 DOI: 10.1128/jb.182.21.5948-5953.2000] [Citation(s) in RCA: 106] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Homologs of the ferric uptake regulator Fur and the iron storage protein ferritin play a central role in maintaining iron homeostasis in bacteria. The gastric pathogen Helicobacter pylori contains an iron-induced prokaryotic ferritin (Pfr) which has been shown to be involved in protection against metal toxicity and a Fur homolog which has not been functionally characterized in H. pylori. Analysis of an isogenic fur-negative mutant revealed that H. pylori Fur is required for metal-dependent regulation of ferritin. Iron starvation, as well as medium supplementation with nickel, zinc, copper, and manganese at nontoxic concentrations, repressed synthesis of ferritin in the wild-type strain but not in the H. pylori fur mutant. Fur-mediated regulation of ferritin synthesis occurs at the mRNA level. With respect to the regulation of ferritin expression, Fur behaves like a global metal-dependent repressor which is activated under iron-restricted conditions but also responds to different metals. Downregulation of ferritin expression by Fur might secure the availability of free iron in the cytoplasm, especially if iron is scarce or titrated out by other metals.
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research-article |
25 |
106 |
2
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Myers RM, Greiner SM, Harvey ME, Griesmann G, Kuffel MJ, Buhrow SA, Reid JM, Federspiel M, Ames MM, Dingli D, Schweikart K, Welch A, Dispenzieri A, Peng KW, Russell SJ. Preclinical pharmacology and toxicology of intravenous MV-NIS, an oncolytic measles virus administered with or without cyclophosphamide. Clin Pharmacol Ther 2007; 82:700-10. [PMID: 17971816 DOI: 10.1038/sj.clpt.6100409] [Citation(s) in RCA: 102] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
MV-NIS is an oncolytic measles virus encoding the human thyroidal sodium iodide symporter (NIS). Here, we report the results of preclinical pharmacology and toxicology studies conducted in support of our clinical protocol "Phase I Trial of Systemic Administration of Edmonston Strain of Measles Virus, Genetically Engineered to Express NIS, with or without Cyclophosphamide, in Patients with Recurrent or Refractory Multiple Myeloma." Dose-response studies in the KAS-6/1 myeloma xenograft model demonstrated a minimum effective dose of 4 x 10(6) TCID50 (tissue culture infectious dose 50)/kg. Toxicity studies in measles-naive squirrel monkeys and measles-susceptible transgenic mice were negative at intravenous doses up to 10(8) and 4 x 10(8) TCID50/kg, respectively. Abundant viral mRNA, maximal on day 8, was detected in cheek swabs of squirrel monkeys, more so after pretreatment with cyclophosphamide. On the basis of these data, the safe starting dose of MV-NIS for our clinical protocol was set at 1-2 x 10(4) TCID50/kg (10(6) TCID50 per patient).
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Research Support, Non-U.S. Gov't |
18 |
102 |
3
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Greiner S, Rausch T, Sonnewald U, Herbers K. Ectopic expression of a tobacco invertase inhibitor homolog prevents cold-induced sweetening of potato tubers. Nat Biotechnol 1999; 17:708-11. [PMID: 10404166 DOI: 10.1038/10924] [Citation(s) in RCA: 102] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
We have transformed potato with Nt-inhh cDNA, encoding a putative vacuolar homolog of a tobacco cell wall invertase inhibitor, under the control of the CaMV 35S promoter. In transgenic tubers, cold-induced hexose accumulation was reduced by up to 75%, without any effect on potato tuber yield. Processing quality of tubers was greatly improved without changing starch quantity or quality, an important prerequisite for the biotechnological use of Nt-inhh for potato transformation.
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26 |
102 |
4
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Conner ME, Zarley CD, Hu B, Parsons S, Drabinski D, Greiner S, Smith R, Jiang B, Corsaro B, Barniak V, Madore HP, Crawford S, Estes MK. Virus-like particles as a rotavirus subunit vaccine. J Infect Dis 1996; 174 Suppl 1:S88-92. [PMID: 8752296 DOI: 10.1093/infdis/174.supplement_1.s88] [Citation(s) in RCA: 97] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
Rotavirus subunit vaccines are being evaluated for use in humans. The virus-like particles (VLPs) for these vaccines are produced in insect cells coinfected with combinations of baculovirus recombinants expressing bovine RIF VP2 and simian SA11, VP4, VP6, or VP7 rotavirus proteins. VLPs were administered parenterally to mice and rabbits, and the immunogenicity and protective efficacy of the vaccines were evaluated. Rabbits vaccinated with VP2/4/6/7 or VP2/6/7 VLP combinations developed high levels of rotavirus-specific serum antibody and fecal IgG but not fecal IgA. The induction of fecal IgG was associated with total or partial protection from oral challenge with ALA rotavirus. Heterotypic serum and fecal neutralizing antibody was induced in mice vaccinated parenterally with G1 VP2/6/7 or VP2/4/6n VLPs. VLPs were highly immunogenic when administered in QS21 adjuvant, inducing serum neutralizing antibody titers comparable to those induced by SA11 virus. VLPs are effective immunogens when administered parenterally and may be an effective subunit vaccine.
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29 |
97 |
5
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Greiner S, Krausgrill S, Rausch T. Cloning of a tobacco apoplasmic invertase inhibitor. Proof of function of the recombinant protein and expression analysis during plant development. PLANT PHYSIOLOGY 1998; 116:733-42. [PMID: 9489020 PMCID: PMC35133 DOI: 10.1104/pp.116.2.733] [Citation(s) in RCA: 88] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/06/1997] [Accepted: 11/07/1997] [Indexed: 05/18/2023]
Abstract
Higher plants express several isoforms of vacuolar and cell wall invertases (CWI), some of which are inactivated by inhibitory proteins at certain stages of plant development. We have purified an apoplasmic inhibitor (INH) of tobacco (Nicotiana tabacum) CWI to homogeneity. Based on sequences from tryptic fragments, we have isolated a full-length INH-encoding cDNA clone (Nt-inh1) via a reverse transcriptase-polymerase chain reaction. Southern-blot analysis revealed that INH is encoded by a single- or low-copy gene. Comparison with expressed sequence tag clones from Arabidopsis thaliana and Citrus unshiu indicated the presence of Nt-inh1-related proteins in other plants. The recombinant Nt-inh1-encoded protein inhibits CWI from tobacco and Chenopodium rubrum suspension-cultured cells and vacuolar invertase from tomato (Lycopersicon esculentum) fruit, whereas yeast invertase is not affected. However, only in the homologous system is the inhibition modulated by the concentration of Suc as previously shown for INH isolated from tobacco cells. Highly specific binding of INH to CWI could be shown by affinity chromatography of a total cell wall protein fraction on immobilized recombinant Nt-inh1 protein. RNA-blot analysis of relative transcript ratios for Nt-inh1 and CWI in different parts of adult tobacco plants revealed that the expression of both proteins is not always coordinate.
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research-article |
27 |
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Greiner S, Haas NP, Bail HJ. Outcome after open reduction and angular stable internal fixation for supra-intercondylar fractures of the distal humerus: preliminary results with the LCP distal humerus system. Arch Orthop Trauma Surg 2008; 128:723-9. [PMID: 17713771 DOI: 10.1007/s00402-007-0428-2] [Citation(s) in RCA: 85] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/16/2007] [Indexed: 01/12/2023]
Abstract
INTRODUCTION Fractures of the distal humerus are complex injuries that can be effectively treated with open reduction and internal fixation (ORIF). The new LCP distal humerus system allows angular stable fixation of these complex fractures with anatomically preshaped plates. The aim of the study was to evaluate operative reposition, fracture healing, and pain, function and patient satisfaction after open reduction with an angular stable fixation. METHODS Fourteen patients with a mean age of 55.2 years (21-83) were treated with open reduction and angular stable internal fixation. Two patients were lost to follow up (1 died, one refused to be reevaluated). AO classification showed 12 C-fractures (1 x C 1.1; 1 x C 1.3; 4 x C 2.2; 4 x C 3.2; 2 x C 3.3) and 2 B-fracture (B 2.3 and B 3.3). 5 fractures were open fractures (4 x II degrees , 1 x I degrees ). The clinical and radiographic follow up (Mayo elbow performance score (MEPS), Dash Score, elbow anterior-posterior and lateral view X-rays, and flexion and extension force as % of contralateral side at 90 degrees flexion) were performed postoperatively. Mean follow up was 10 months. RESULTS Radiographically, complete union was achieved in all patients. There were no cases of primary malposition or secondary dislocation. Complications were: (1) delayed union after olecranon osteotomy, (2) transient ulnar nerve irritation. Clinical MEPS results were good to excellent with a mean of 91 +/- 11.7 points. The mean DASH Score was 18.5 +/- 11.5 points. Mean flexion was 121 +/- 20.9, mean extension deficit was 17.9 degrees +/- 10.3. Mean flexion force was 75.3% +/- 26.7 and mean extension force was 70.7 % +/- 24.9. CONCLUSION Treatment of supra-intercondylar fractures of the distal humerus is challenging. Anatomically preshaped angular stable implants facilitate operative reduction and stabilization of the fracture and may allow early postoperative rehabilitation. Clinical and radiological results are promising, with good range of motion and flexion and extension force.
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17 |
85 |
7
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Peng KW, Myers R, Greenslade A, Mader E, Greiner S, Federspiel MJ, Dispenzieri A, Russell SJ. Using clinically approved cyclophosphamide regimens to control the humoral immune response to oncolytic viruses. Gene Ther 2012; 20:255-61. [PMID: 22476202 DOI: 10.1038/gt.2012.31] [Citation(s) in RCA: 83] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
Oncolytic viruses can be neutralized in the bloodstream by antiviral antibodies whose titers increase progressively with each exposure, resulting in faster virus inactivation and further reductions in efficacy with each successive dose. A single dose of cyclophosphamide (CPA) at 370 mg m(-2) was not sufficient to control the primary antiviral immune responses in mice, squirrel monkeys and humans. We therefore tested clinically approved multidose CPA regimens, which are known to kill proliferating lymphocytes, to determine if more intensive CPA therapy can more effectively suppress antiviral antibody responses during virotherapy. In virus-susceptible mice, primary antibody responses to intravenously (i.v.) administered oncolytic measles virus (MV) or vesicular stomatitis virus (VSV) were partially or completely suppressed, respectively, by oral (1 mg × 8 days) or systemic (3 mg × 4 days) CPA regimens initiated 1 day before virus. When MV- or VSV-immune mice were re-challenged with the respective viruses and concurrently treated with four daily systemic doses of CPA, their anamnestic antibody responses were completely suppressed and antiviral antibody titers fell significantly below pre-booster levels. We conclude that the CPA regimen of four daily doses at 370 mg m(-2) should be evaluated clinically with i.v. virotherapy to control the antiviral antibody response and facilitate effective repeat dosing.
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Research Support, Non-U.S. Gov't |
13 |
83 |
8
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Greiner S, Kääb MJ, Haas NP, Bail HJ. Humeral head necrosis rate at mid-term follow-up after open reduction and angular stable plate fixation for proximal humeral fractures. Injury 2009; 40:186-91. [PMID: 19100544 DOI: 10.1016/j.injury.2008.05.030] [Citation(s) in RCA: 81] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/07/2008] [Revised: 05/22/2008] [Accepted: 05/23/2008] [Indexed: 02/02/2023]
Abstract
INTRODUCTION Short-term follow-up of angular stable fixation for proximal humeral fractures has been well documented in the literature. Longer follow-up series are difficult to find. However, especially regarding the risk of avascular humeral head necrosis longer follow-up series are high of clinical relevance. METHODS Forty-eight patients with a mean age of 66 years and treated with open reduction and angular stable internal fixation for proximal humeral fractures were followed up for a mean of 45 months. The clinical and radiographic follow-up (Constant Score (CS), age and gender related Constant Score (agCS), Constant Score in comparison to the contralateral side (%CS) and shoulder anterior-posterior and lateral view and axial view X-rays) was performed postoperatively. RESULTS Clinical results after 45 months showed a mean CS of 66.2+/-15.4 points with a mean agCS of 90.0+/-23.1%. Evaluation of the %CS showed 77.7+/-17.8%. %CS results showed no significant differences after 45 months in comparison to those obtained after 12 months. However, incidence of avascular necrosis of the humeral head doubled over the follow-up period from 4 cases at 12 months follow-up to 9 cases at final follow-up. CONCLUSION Results of open reduction and internal fixation with angular stable implants for proximal humeral fractures are reliable, however long-term complications such as avascular necrosis of the humeral head need to be evaluated further on since its incidence increases over the time.
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81 |
9
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Herrmann S, Schmidmaier G, Greiner S. Stabilisation of vertical unstable distal clavicular fractures (Neer 2b) using locking T-plates and suture anchors. Injury 2009; 40:236-9. [PMID: 19168176 DOI: 10.1016/j.injury.2008.07.021] [Citation(s) in RCA: 63] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/23/2008] [Revised: 07/10/2008] [Accepted: 07/11/2008] [Indexed: 02/02/2023]
Abstract
Distal clavicular fractures are associated with an increased risk of delayed union and non-union, and therefore operative treatment is favoured. Fragment dislocation and instability result from detachment of the coracoclavicular ligaments. Various methods for operative treatment can be found in the literature, but no gold standard has been established. In this retrospective study, we present a new surgical technique using a locking T-plate for osseous stabilisation in combination with vertical stabilisation by suture anchors. Between October 2006 and December 2007, eight people underwent surgery for unstable distal clavicular fracture (Neer type 2b). Subsequently one patient could only be contacted by phone and was excluded from further analysis. Mean follow-up for the remaining seven individuals was 8.3 months. The Constant and DASH scores were evaluated and stress radiographs were performed to check for vertical instability. In all cases bony union was achieved within 6 weeks postoperatively. No intraoperative or early postoperative complications were observed. All but one patient regained excellent shoulder function, the mean Constant and DASH scores were 93.3 and 15.3, respectively. Coracoclavicular distance was successfully restored with a mean 1mm (range 0-2mm) side-to-side difference. Early clinical and radiographic results of this new method are promising, with good to excellent outcome in all cases.
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Evaluation Study |
16 |
63 |
10
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Pauly S, Klatte F, Strobel C, Schmidmaier G, Greiner S, Scheibel M, Wildemann B, Wildemann B. Characterization of tendon cell cultures of the human rotator cuff. Eur Cell Mater 2010; 20:84-97. [PMID: 20661865 DOI: 10.22203/ecm.v020a08] [Citation(s) in RCA: 61] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
Rotator cuff tears are common soft tissue injuries of the musculoskeletal system that heal by formation of repair tissue and may lead to high retear rates and joint dysfunction. In particular, tissue from chronic, large tendon tears is of such degenerative nature that it may be prone to retear after surgical repair. Besides several biomechanical approaches, biologically based strategies such as application of growth factors may be promising for increasing cell activity and production of extracellular tendon matrix at the tendon-to-bone unit. As a precondition for subsequent experimental growth factor application, the aim of the present study was to establish and characterize a human rotator cuff tendon cell culture. Long head biceps (LHB)- and supraspinatus muscle (SSP)- tendon samples from donor patients undergoing shoulder surgery were cultivated and examined at the RNA level for expression of collagen type-I, -II and -III, biglycan, decorin, tenascin-C, aggrecan, osteocalcin, tenomodulin and scleraxis (by Real-time PCR). Finally, results were compared to chondrocytes and osteoblasts as control cells. An expression pattern was found which may reflect a human rotator cuff tenocyte-like cell culture. Both SSP and LHB tenocyte-like cells differed from chondrocyte cell cultures in terms of reduced expression of collagen type-II (p<or=0.05) and decorin while higher levels of collagen type-I were seen (p<or=0.05). With respect to osteoblasts, tenocyte-like cells expressed lower levels of osteocalcin (p<or=0.05) as well as tenascin C, biglycan and collagen type-III. Expression of scleraxis, tenomodulin and aggrecan was similar between all cell types. This study represents a characterization of tenocyte-like cells from the human rotator cuff as close as possible. It helps analyzing their biological properties and allows further studies to improve production of tendon matrix and osteofibroblastic integration at the tendon-bone unit following tendon repair.
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15 |
61 |
11
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Klatte-Schulz F, Pauly S, Scheibel M, Greiner S, Gerhardt C, Schmidmaier G, Wildemann B. Influence of age on the cell biological characteristics and the stimulation potential of male human tenocyte-like cells. Eur Cell Mater 2012; 24:74-89. [PMID: 22791374 DOI: 10.22203/ecm.v024a06] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
The incidence of rotator cuff tears and recurrent defects positively correlate with patient age. However, this observation has never been analysed at the cellular level. The present study aims to better understand this correlation by investigating cellular characteristics of rotator cuff tenocytes of different age groups. Additionally, previous studies reported on stimulating effects of Bone Morphogenetic Protein (BMP) -2 and BMP-7 on tenocytes. Thus, the second aim was to investigate, whether the stimulation potential of tenocytes demonstrates age-related differences. Tenocyte-like cells from supraspinatus tendons of young and aged patients were analysed for the following cell biological characteristics: cell density, cell growth, marker expression, collagen-I protein synthesis, stem cell phenotype, potential for multipotent differentiation and self-renewal. To analyse the stimulation potential, cells were treated with BMP-2 and BMP-7 in 2D-/3D-cultures. Measured parameters included cell activity, marker expression and collagen-I protein synthesis. An effect of age was seen for cell growth and stem cell potential but not on extracellular matrix level. Cells from both groups responded to BMP-7 by increasing cell activity, collagen-I expression and protein synthesis. BMP-2 led to smaller increases in these parameters when compared to BMP-7. In general, 3D-cultivation improved the stimulation compared to 2D-culture. The cell biological characteristics of tenocyte-like cells, considered important for successful restoration of the tendon-bone unit, were inferior in elderly donors. This may help explain higher rates of recurrent defects seen in elderly patients. Regarding the stimulation potential, on a cellular level young and aged patients may benefit from biological augmentation with BMPs.
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59 |
12
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Schäfer HJ, Greiner S, Rausch T, Haag-Kerwer A. In seedlings of the heavy metal accumulator Brassica juncea Cu2+ differentially affects transcript amounts for gamma-glutamylcysteine synthetase (gamma-ECS) and metallothionein (MT2). FEBS Lett 1997; 404:216-20. [PMID: 9119067 DOI: 10.1016/s0014-5793(97)00132-4] [Citation(s) in RCA: 59] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Glutathione (GSH) is the precursor of the phytochelatins (PC), which in plants and fungi are involved in heavy metal sequestration. The regulatory enzyme gamma-glutamylcysteine synthetase (gamma-ECS) catalyzes the first step in GSH biosynthesis. For the heavy metal accumulator Brassica juncea L. a partial gamma-ECS cDNA was cloned by RT-PCR. Treatment of suspension-cultured dark grown seedlings with micromolar concentrations of CuSO4 resulted in a strong increase of gamma-ECS mRNA in roots and shoots, concomitant with an increase of GSH and phytochelatins. A significant up-regulation of gamma-ECS mRNA was observed at 25 microM CuSO4 (shoot growth: -11%), whereas maximum up-regulation was obtained at 100 microM CuSO4 (shoot growth: -60%). Unexpectedly, metallothionein 2 (MT2) mRNA was decreased in response to the CuSO4 treatments. CdSO4 at a concentration of 50 microM caused a 72% reduction in shoot growth without affecting the amounts of gamma-ECS- and MT2 mRNAs. ZnSO4 at a concentration of 500 microM did not reduce growth but induced transient increases of gamma-ECS- and MT2 mRNAs. The implications of the results with respect to differential regulation of gamma-ECS and MT2 during heavy metal exposure are discussed.
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28 |
59 |
13
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Peng KW, Hadac EM, Anderson BD, Myers R, Harvey M, Greiner SM, Soeffker D, Federspiel MJ, Russell SJ. Pharmacokinetics of oncolytic measles virotherapy: eventual equilibrium between virus and tumor in an ovarian cancer xenograft model. Cancer Gene Ther 2006; 13:732-8. [PMID: 16543921 DOI: 10.1038/sj.cgt.7700948] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Because of their ability to replicate, the dose-response relationships of oncolytic viruses cannot easily be predicted. To better understand the pharmacokinetics of virotherapy in relation to viral dose and schedule, we administered MV-CEA intraperitoneally in an orthotopic mouse model of ovarian cancer. MV-CEA is an attenuated oncolytic measles virus engineered to express soluble human carcinoembryonic antigen (CEA), and the virus is currently undergoing phase I clinical testing in patients with ovarian cancer. Plasma CEA levels correlate with numbers of virus-infected tumor cells at a given time, and were used as a surrogate to monitor the profiles of viral gene expression over time. The antineoplastic activity of single- or multiple-dose MV-CEA was apparent over a wide range of virus doses (10(3)-10(8) TCID(50)), with little reduction in observed antitumor efficacy, even at the lowest tested dose. However, analysis of CEA profiles of treated mice was highly informative, illustrating the variability in virus kinetics at different dose levels. The highest doses of virus were associated with higher initial levels of tumor cell killing, but the final outcome of MV-CEA therapy at all dose levels was a partial equilibrium between virus and tumor, resulting in significant slowing of tumor growth and enhanced survival of the mice.
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50 |
14
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Greiner S, Humrich JY, Thuman P, Sauter B, Schuler G, Jenne L. The highly attenuated vaccinia virus strain modified virus Ankara induces apoptosis in melanoma cells and allows bystander dendritic cells to generate a potent anti-tumoral immunity. Clin Exp Immunol 2007; 146:344-53. [PMID: 17034588 PMCID: PMC1942054 DOI: 10.1111/j.1365-2249.2006.03177.x] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
Vaccinia virus (VV) has been tested as oncolytic virus against malignant melanoma in clinical trials for more than 40 years. Until now, mainly strains comparable to viral strains used for smallpox vaccination have been probed for anti-tumoral therapy. We have shown recently that the wild-type strain Western Reserve (WR) can interfere with crucial functions of monocyte-derived dendritic cells (DCs). Our aim was to examine whether viral immune evasion mechanisms might be responsible for the ineffectiveness of WR-based vaccination strategies and whether the highly attenuated strain modified virus Ankara (MVA) differs from WR with respect to its possible immunostimulatory capacity after intratumoral injection. Using in vitro experiments, we compared the effect of both strains on melanoma cells and on local bystander DCs. We found that both VV-strains infected melanoma cells efficiently and caused disintegration of the actin cytoskeleton, as shown by fluorescence microscopy. In addition, both VV-strains caused apoptotic cell death in melanoma cells after infection. In contrast to MVA, WR underwent a complete viral replication cycle in melanoma cells. Bystander DCs were consecutively infected by newly generated WR virions and lost their capacity to induce allogeneic T cell proliferation. DCs in contact with MVA-infected melanoma cells retained their capacity to induce T cell proliferation. Immature DCs were capable of phagocytosing MVA-infected melanoma cells. Priming of autologous CD8(+) T cells by DCs that had phagocytosed MVA-infected, MelanA positive melanoma cells resulted in the induction of T cell clones specifically reactive against the model antigen MelanA as shown by enzyme-linked immunospot (ELISPOT) analysis. We conclude that the clinical trials with oncolytic wild-type VV failed probably because of suppression of bystander DCs and consecutive suppression of T cell-mediated anti-melanoma immunity. The attenuated VV-strain MVA facilitates the generation of tumour associated antigen (TAA)-specific T cell response as it is oncolytic for melanoma cells, but non-toxic for DC, and should be a promising candidate for intralesional metastatic melanoma therapy.
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Research Support, Non-U.S. Gov't |
18 |
49 |
15
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Hammadeh ME, Greiner S, Rosenbaum P, Schmidt W. Comparison between human sperm preservation medium and TEST-yolk buffer on protecting chromatin and morphology integrity of human spermatozoa in fertile and subfertile men after freeze-thawing procedure. JOURNAL OF ANDROLOGY 2001; 22:1012-8. [PMID: 11700849 DOI: 10.1002/j.1939-4640.2001.tb03442.x] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
The aim of this study was to identify the detrimental effect of the freeze-thaw process on chromatin integrity and morphology of human spermatozoa, and to determine whether human sperm preservation medium (HSPM) or TEST-yolk buffer (TYB) offers a better protection to spermatozoa from cryodamage after the freeze-thaw procedure. Thirty-five semen samples obtained from couples childless because of male factor infertility (subfertile men, group 1) and 25 semen samples from healthy, normal volunteers of proven fertility (group 2) were included in the study. Each semen sample was divided into 2 parts, the first part was mixed with HSPM and the other with TYB (1:1), and frozen with a controlled slow-stage freezer, before plunging into liquid nitrogen. Twelve smears from each semen sample were made before (n = 4) and after (n = 8) the freeze-thaw process. Chromatin structure was evaluated after staining using the acridine orange (AO) test, whereas morphology was analyzed according to strict criteria. The mean percentage of spermatozoa that exhibited normal morphology and intact chromatin structure was decreased after freeze-thaw in all samples treated with HSPM or TYB in comparison with the value observed in the native semen samples of both groups. However, TYB preserved chromatin and morphology significantly better than HSPM did (9.3% +/- 5.6% and 88.7% +/- 11.2% vs. 7.8% +/- 4.2% and 85.5% +/- 12.5%, respectively). Therefore, TYB could be recommended as a first choice cryoprotectant for semen preservation in order to avoid extra chromatin structure damage and morphology alterations of spermatozoa not only for patients pursuing assisted reproduction, but also for donor samples.
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Comparative Study |
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38 |
16
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Greiner S, Kadow-Romacker A, Lübberstedt M, Schmidmaier G, Wildemann B. The effect of zoledronic acid incorporated in a poly(D,L-lactide) implant coating on osteoblasts in vitro. J Biomed Mater Res A 2007; 80:769-75. [PMID: 17041912 DOI: 10.1002/jbm.a.30950] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Bisphosphonates such as zoledronic acid (ZOL) are used in diseases associated with osteoclast-mediated bone loss. However, their antiresorptive activity is partly due to their effect on osteoblasts. Local application might increase the therapeutical fence and their local efficiency and reduce systemic side effects. Aim of the study was to investigate the effect of ZOL on human osteoblasts like cells in vitro with special focus on the synthesis of factors mediating osteoclast differentiation (RANKL, OPG). ZOL was incorporated in an implant coating based on poly(D,L-lactide) (PDLLA) in different concentrations (10-150 microM). Control groups were treated with uncoated implants, PDLLA-coated implants, and ZOL pure substance in corresponding concentrations. After an experimental period of 144 h, primary human osteoblasts were stained with alamar blue and cell viability was measured. Procollagen I synthesis, osteoprotegerin (OPG) secretion, and soluble receptor activator of nuclear factor-kappaB ligand (sRANKL) were analyzed. Results showed that cell viability was not affected when treated with doses equivalent up to 100 microM ZOL-coated implants (ZOL-CI). Procollagen I synthesis was highest when treated with 50 microM ZOL-CI. OPG increased significantly in the 10 microM ZOL-CI group, whereas sRANKL decreased significantly with different concentrations of ZOL-CI. Higher concentrations or exposure to the pure substance showed a decrease in cell viability, collagen I, OPG, and sRANKL synthesis. In conclusion, exposure to specific concentrations of ZOL-CI showed a beneficial effect on osteoblast differentiation and protein synthesis without influencing their proliferation. Changes in sRANKL and OPG production may contribute to the inhibition of osteoclastic bone resorption. This local antiresorptive effect might be clinically useful in osseous implant integration and fracture healing.
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Journal Article |
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Madore HP, Estes MK, Zarley CD, Hu B, Parsons S, Digravio D, Greiner S, Smith R, Jiang B, Corsaro B, Barniak V, Crawford S, Conner ME. Biochemical and immunologic comparison of virus-like particles for a rotavirus subunit vaccine. Vaccine 1999; 17:2461-71. [PMID: 10392629 DOI: 10.1016/s0264-410x(98)00319-3] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A parenterally administered rotavirus vaccine composed of virus-like particles (VLPs) is being evaluated for human use. VLPs composed of bovine VP6 and simian VP7 (SA11, G3) proteins (6/7-VLPs) or of bovine VP2, bovine VP6, and simian VP7 (SA11, G3) proteins (2/6/7-VLPs) were synthesized and purified from Sf9 insect cells co-infected with recombinant baculoviruses. 6/7- and 2/6/7-VLP administered parenterally (i.m.) in mice had comparable immunogenicity, but the 2/6/7-VLPs were more homogeneous and stable. The inclusion of the VP2 capsid contributed to particle formation and stability. The adjuvant QS-21 significantly enhanced the immunogenicity of 2/6/7-VLPs over A10H or saline alone. Equivalent serum neutralizing antibody responses were induced over the range of 1-15 microg/dose of 2/6/7-VLPs administered with the range of 5-20 microg/dose of QS-21. The immunogenicity of 2/6/7-VLPs and inactivated SA11 virus were comparable. 2/6/7-VLPs are a promising candidate for a parenterally delivered rotavirus subunit vaccine.
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Comparative Study |
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Rosenkranz H, Vogel R, Greiner S, Rausch T. In wounded sugar beet (Beta vulgaris L.) tap-root, hexose accumulation correlates with the induction of a vacuolar invertase isoform. JOURNAL OF EXPERIMENTAL BOTANY 2001; 52:2381-2385. [PMID: 11709588 DOI: 10.1093/jexbot/52.365.2381] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Wounding of sugar beet tap-root causes an induction of invertase activity, which contributes to post-harvest sucrose losses. In this first comprehensive monitoring of wound-induced invertase mRNAs, proteins, enzyme activities, and tissue hexose concentrations, the VI isoform responsible for wound-induced hexose accumulation in mature tap-root could be identified.
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Sander A, Krausgrill S, Greiner S, Weil M, Rausch T. Sucrose protects cell wall invertase but not vacuolar invertase against proteinaceous inhibitors. FEBS Lett 1996; 385:171-5. [PMID: 8647244 DOI: 10.1016/0014-5793(96)00378-x] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Vacuolar (VI) and cell wall invertases (CWI) of higher plants can be inactivated in vitro and, possibly, in vivo by proteinaceous inhibitors. The respective mechanisms have not yet been compared. Therefore, partially purified CWI from transformed tobacco cells and VI from tomato fruit were preincubated with invertase-inhibitor fractions isolated from the same tissues. Both inhibitors were able to inhibit both invertases. However, VI was fully inhibited within less than 1 min by both inhibitors, whereas inactivation of CWI was much slower. Furthermore, CWI, but not VI, was strongly protected against inhibition by sucrose. A polyclonal antiserum directed against the tobacco inhibitor (I(NT)) cross-reacted with a 19 kDa polypeptide in the partially purified tomato inhibitor (I(LE)) fraction. The results indicate that I(NT) and I(LE)have similar structural properties, whereas the mechanism of inactivation is clearly different for CWI and VI.
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Greiner S, Kadow-Romacker A, Schmidmaier G, Wildemann B. Cocultures of osteoblasts and osteoclasts are influenced by local application of zoledronic acid incorporated in a poly(D,L-lactide) implant coating. J Biomed Mater Res A 2009; 91:288-95. [PMID: 18980195 DOI: 10.1002/jbm.a.32245] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
The antiresorptive activity of bisphosphonates such as zoledronic acid (ZOL) has been shown in vitro to be because of their effect on osteoclasts and osteoblasts. However, whether the effect of ZOL on monocultures might be reproducible on cocultures and whether cell interactions might influence this effect has not been described. The aim of the study was to investigate the effect of ZOL on cocultures of osteoblasts and osteoclasts in vitro. ZOL was incorporated in an implant coating based on poly(D,L-lactide) in different concentrations (10-50 microM). Cell number was measured, and procollagen I synthesis, osteoprotegerin (OPG) secretion and soluble receptor activator of nuclear factor-kappaB ligand (sRANKL) were analyzed. Moreover, TRAP-positive cells and resorption lacunas on dentin chips were counted. Results showed that cell viability was not affected when treated with doses equivalent up to 50-microM ZOL-coated implants (ZOL-CI). Procollagen I and OPG synthesis was highest when treated with 10 microM ZOL-CI, whereas sRANKL showed no significant decrease when treated with the investigated concentrations of ZOL-CI. TRAP-positive cells were decreased when treated with ZOL-CI in a dose-dependent manner. Resorption activity of osteoclasts was not significantly decreased when treated with investigated concentrations of ZOL-CI. Exposure to specific concentrations of ZOL-CI showed a beneficial effect on osteoblast differentiation and protein synthesis. Formation of osteoclast was decreased, whereas a significant decrease in sRANKL secretion and resorption activity of osteoclasts could not be shown. The investigated effect on cocultures might be clinically useful to support fracture healing and to reduce orthopedic implant loosening.
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Journal Article |
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Friess H, Büchler M, Auerbach B, Weber A, Malfertheiner P, Hammer K, Madry N, Greiner S, Bosslet K, Beger HG. CA 494--a new tumor marker for the diagnosis of pancreatic cancer. Int J Cancer 1993; 53:759-63. [PMID: 8449599 DOI: 10.1002/ijc.2910530509] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
In 59 patients with ductal pancreatic cancer the monoclonal antibody (MAb) BW 494, which detects the CA 494 glycoprotein antigen, was analyzed in comparison with the reference tumor markers CA 19-9 and CEA. Eighty-one patients with non-pancreatic malignancies of the gastrointestinal (GI) tract, 95 with chronic pancreatitis, 124 with benign non-pancreatic GI diseases, 30 with diabetes mellitus (type I or type II) and 114 healthy blood donors served as controls. The sensitivity of pancreatic cancer was 90%, 44% and 90% for CA 19-9, CEA and CA 494, respectively. In chronic pancreatitis, as the most important control population for pancreatic cancer, the specificity was 85%, 72% and 94% for CA 19-9, CEA and CA 494, respectively.
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Gerhardt C, Kraus N, Greiner S, Scheibel M. [Arthroscopic stabilization of acute acromioclavicular joint dislocation]. DER ORTHOPADE 2011; 40:61-9. [PMID: 21170517 DOI: 10.1007/s00132-010-1680-7] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
During the past few years arthroscopic and minimal invasive techniques for stabilization of acromioclavicular (AC) joint dislocations have gained increasing interest. Well established procedures for open surgery were modified and implemented to attain an arthroscopic level. Furthermore implants were developed which enable these reconstructive techniques to be performed arthroscopically without the disadvantages of open procedures. The short to mid-term results described so far concerning the clinical and radiological outcome of arthroscopic stabilization techniques show an at least equal outcome to those presented in open surgery.
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Journal Article |
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Bereswill S, Lichte F, Greiner S, Waidner B, Fassbinder F, Kist M. The ferric uptake regulator (Fur) homologue of Helicobacter pylori: functional analysis of the coding gene and controlled production of the recombinant protein in Escherichia coli. Med Microbiol Immunol 1999; 188:31-40. [PMID: 10691091 DOI: 10.1007/s004300050102] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
A homologue of the ferric uptake regulator protein Fur has recently been identified within the Helicobacter pylori genome. The promoterless gene on a plasmid did partially complement a fur-negative mutant of Escherichia coli, and was strongly positive in the Fur titration assay (FURTA). The genetic and functional characterization of the complete fur homologue performed in this study revealed that the gene is conserved among H. pylori strains ( > 95% identity), and does not carry nucleotide transitions in iron-resistant mutants of H. pylori. The fur homologue on a plasmid mediated full iron-dependent ferric uptake regulator activity in the fur-deficient mutant strains H1681 and H1780 of E. coli. Immunoblot analysis revealed that Fur from H. pylori cross-reacts with antibodies raised against Fur from E. coli. The fact that inactivation of the fur gene abolished the FURTA-positive phenotype in the E. coli indicator strain H1717, indicated that this phenotype is rather caused by the encoded protein than by real Fur titration. Subcloning of the fur gene into an expression vector allowed controlled production in E. coli, and purification of a recombinant version of the H. pylori Fur protein. In summary, the results confirm the function of the H. pylori Fur homologue as iron-dependent transcriptional repressor by its ability to interact with the Fur-regulated promoters of the genes fiu and fhuF in E. coli.
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Eberhart LHJ, Greiner S, Geldner G, Wulf H. [Patient evaluation of postoperative recovery. An evaluation of the QoR scores in 577 patients]. Anaesthesist 2002; 51:463-6. [PMID: 12391532 DOI: 10.1007/s00101-002-0322-9] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
BACKGROUND In 1999 Myles and co-workers presented their quality of recovery score (QoR score) as a tool to evaluate postoperative recovery and to measure patient satisfaction. It was developed according to predefined psychological standards and its reliability and validity had been proven in large clinical trials. The aim of this study was to evaluate a German version of the QoR in a heterogeneous group of surgical patients. METHODS A total of 577 unselected patients completed a modified questionnaire. The response rate and time spent on completing the test were recorded. A stepwise multivariate regression analysis identified factors with significant impact on the QoR score. Other analyses were performed descriptively. RESULTS Of the patients 83% completed the questionnaire in a median time of 9 h after surgery without assistance. For 75% of these it took 2 min or less. The median QoR score was 15 (10(th)/90(th) percentile: 11/18). Cronbach's p (=0.63) and mean corrected item correlation (=0.32) were used as measures of internal reliability. Factors with impact on the QoR score were: period of time after surgery when performing the test, severity of surgery, sex, general vs local anaesthesia, duration of anaesthesia, and age. CONCLUSIONS The German translation of the QoR score is easily applicable to a heterogeneous surgical population and thus can be used as a valuable measure of quality of anaesthesia care and patient satisfaction.
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Clinical Trial |
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Greiner S, Weil M, Krausgrill S, Rausch T. A tobacco cDNA coding for cell-wall invertase. PLANT PHYSIOLOGY 1995; 108:825-6. [PMID: 7610171 PMCID: PMC157407 DOI: 10.1104/pp.108.2.825] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
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Comparative Study |
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14 |