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21.
Andreas Lange Claudia Kistler Tanja B. Jutzi Alexandr V. Bazhin Claus Detlev Klemke Dirk Schadendorf Stefan B. Eichmüller 《Experimental dermatology》2009,18(6):527-535
Abstract: The identification of tumor-specific proteins located at the plasma membrane is hampered by numerous methodological pitfalls many of which are associated with the post-translational modification of such proteins. Here, we present a new combination of detergent fractionation of cells and of subtractive suppression hybridization (SSH) to gain overexpressed genes coding for membrane-associated or secreted proteins. Fractionation of subcellular components by digitonin allowed sequestering mRNA of the rough Endoplasmatic reticulum and thereby increasing the percentage of sequences coding for membrane-bound proteins. Fractionated mRNAs from the cutaneous T-cell lymphoma (CTCL) cell line HuT78 and from normal peripheral blood monocytes were used for SSH leading to the enrichment of sequences overexpressed in the tumor cells. We identified some 21 overexpressed genes, among them are GPR137B, FAM62A, NOMO1, HSP90, SLIT1, IBP2, CLIF, IRAK and ARC. mRNA expression was tested for selected genes in CTCL cell lines, skin specimens and peripheral blood samples from CTCL patients and healthy donors. Several of the detected sequences are clearly related to cancer, but have not yet been associated with CTCL. qPCR confirmed an enrichment of these mRNAs in the rough endoplasmic reticulum fraction. RT-PCR confirmed the expression of these genes in skin specimens and peripheral blood of CTCL patients. Western blotting verified protein expression of HSP90 and IBP2 in HuT78. GPR137B could be detected by immunohistology in HuT78 and in keratinocytes of dysplastic epidermis, but also in sweat glands of healthy skin. In summary, we developed a new technique, which allows identifying overexpressed genes coding preferentially for membrane-associated proteins. 相似文献
22.
Germ cell tumors of the testes represent a unique paradigm of diseases which can be cured even in extremely advanced phase.
Unfortunately, this makes them unique among adult solid tumors. Seminoma and non seminoma are relatively rare with approximatively
25,000 patients in Europe per year, but numbers are increasing world wide. Different strategies are needed depending on stage
and prognostic scores. Seminoma is extremely sensitive to radiation therapy and chemotherapy, while all germ cell tumors show
a very good response to chemotherapy. Clinical stage I seminoma is currently treated with radiation, single course carboplatin
or surveillance policy. Clinical stage I non seminoma can also be approached with different strategies such as retroperitoneal
lymph node dissection, observation or one-two courses of standard chemotherapy. Stage II seminoma may be treated with either
radiation or chemotherapy, while for all advanced stages chemotherapy is mandatory. Since the mid-eighties PEB (Cisplatin,
Etoposide and Bleomycin) is the regimen of choice and no other schedule has proved superior in terms of efficacy. Surgery
on the residual disease is crucial to the whole strategy and should be performed or attempted in all cases. Consequently,
the correct treatment strategy for these tumors does not depend only on the ability of a single physician, but on a skilled
team specialized in this particular tumor. Second line therapies (VeIP, PEI, TIP) can cure 25%–40% of patients, but improved
strategies for resistant tumors are desperately needed. High-dose chemotherapy has shown very good results in some studies
while being less impressive in others. In any case, it should remain an option for relapsing patients and could be used in
some cases of upfront chemotherapy in patients with slow marker decline, but this should only be considered in referring centers. 相似文献
23.
Manuela Kusch Claudia Grundmann Stefanie Keitel Rainer Seitz Herbert K?nig 《Blood coagulation & fibrinolysis》2006,17(7):575-580
A novel assay for factor XIII is described that utilizes exclusively small synthetic peptides as substrates for the cross-linking reaction catalyzed by activated factor XIII (FXIIIa). The acyl donor substrate (selection peptide) is immobilized on a microplate via biotin while the acyl acceptor substrate (detection peptide) is labeled with the fluorochrome Oregon green to allow sensitive detection without the need for secondary enzyme systems for signal amplification. Starting with an amino acid sequence from the fibrin gamma-chain (GQQHHLGGAKQAGDV) as a prototype peptide, the influence of amino acid exchanges were investigated with respect to their impact on the FXIIIa-catalyzed reaction. It was found that FXIIIa readily accepts a broad range of substrate peptides, with a proline neighboring the essential lysine having the most detrimental effect. The assay appears to be valuable for the molecular characterization of factor XIII and may be used for a deeper investigation into the substrate requirements of this final enzyme of wound repair, and eventually also for the characterization of other transglutaminases. 相似文献
24.
25.
The Mauthner cell (M-cell) of the ‘weakly electric fish’ Gymnotus carapo was investigated with electrophysiological techniques. The antidromic action potential, the recurrent inhibitory input and the posterior VIIIth nerve excitatory input in this cell exhibited characteristics similar to those described in the goldfish. In addition, we found an excitatory input evoked by spinal stimulation at intensities subthreshold for M-cell axons. 相似文献
26.
The efficacy of intravenous thrombolytic agents in preserving left ventricular function and in decreasing mortality from an acute myocardial infarction was demonstrated in the 1980s. The 1990s will concentrate on adjunctive therapy to thrombolysis in the treatment of an acute myocardial infarction. 相似文献
27.
Kathryn A Atchison Melanie W Gironda Edward E Black Stuart Schweitzer Claudia Der-Martirosian Alan Felsenfeld Richard Leathers Thomas R Belin 《Journal of oral and maxillofacial surgery》2007,65(12):2430-2437
PURPOSE: Patient preferences for treatment choices may depend on patient characteristics. Using standard gamble (SG) and willingness to pay (WTP), this study compares preferences for treatment of mandibular fracture among patients in a low-income urban area. PATIENTS AND METHODS: Surveys of African-American and Hispanic adults receiving treatment at King/Drew Medical Center for either mandibular fracture (n = 98) or third molar removal (n = 105) were used to investigate differences in patient characteristics across treatment groups (third molar vs fracture) and treatment preference (wiring vs surgery). RESULTS: The fracture patients were willing to pay more to restore function without scarring or nerve damage than were the third molar patients. Patients who chose surgery were willing to accept a greater risk of possible nerve damage or scarring than those who chose wiring. Among 15 potential predictors of SG and WTP studied in 4 subgroups defined by actual treatment and treatment preference, significant predictors varied, with associations for education and clinical experience for SG and associations with income and psychosocial predictors for WTP. CONCLUSIONS: SG and WTP capture different domains of health values in patients. There is considerable heterogeneity in relationships among patient characteristics and patient preferences across subgroups defined by actual treatment and treatment preferences. 相似文献
28.
Claudia E E Noffke Erich J Raubenheimer Ntombizonke J Chabikuli Michael M R Bouckaert 《Oral surgery, oral medicine, oral pathology, oral radiology, and endodontics》2007,104(1):101-109
OBJECTIVE: The purpose of the study was to analyze the clinical and radiographic features of central odontogenic myxomas (OM) of the jaws diagnosed over 23 years in a black South African patient sample. STUDY DESIGN: Records of 30 cases of OMs with radiographs of diagnostic quality were retrieved from 52 cases of histopathologically verified OMs from the archives of the Oral Health Center at the University of Limpopo, South Africa. The age, sex, size, location, and radiographic features were compared with the literature. RESULTS: The study consisted of 21 females and 9 males. The correlation between age and size of the tumor was found to be statistically significant (P = .004). Septa were shown to be either reorientated cortical bone or sheets of dense fibrous connective tissue. Indistinct borders mimicked malignancy. The most common radiographic feature was the tennis-racket appearance. CONCLUSIONS: Variations in radiographic presentation make a radiological differential interpretation of OM challenging because the radiographic features overlap with those of other benign and malignant neoplasms. 相似文献
29.
Antonio Gigante Claudia Bevilacqua Andrea Ricevuto Monica Mattioli-Belmonte Francesco Greco 《Knee surgery, sports traumatology, arthroscopy》2007,15(1):88-92
The implantation of chondrocytes, seeded on matrices such as hyaluronic acid or collagen membranes, is a method that is being widely used for the treatment of chondral defects. The aim of the present study was to evaluate the distribution, viability and phenotype expression of the cells seeded on a collagen membrane just at the time of the implantation. Twelve patients who were suffering from articular cartilage lesions were treated by the MACI® procedure. The residual part of each membrane was tested by colorimetric assay (MTT) and histochemical and ultrastructural analyses were carried out. In all of the samples a large number of viable cells, quite homogenously distributed, was detected. The cells expressed the markers of the differentiated hyaline chondrocytes. These data reassure in that the MACI procedure provides a suitable engineered tissue for cartilage repair, in line with the clinical evidences emerging in the literature. 相似文献
30.
Tariquidar-induced P-glycoprotein inhibition at the rat blood-brain barrier studied with (R)-11C-verapamil and PET. 总被引:1,自引:0,他引:1
Jens P Bankstahl Claudia Kuntner Aiman Abrahim Rudolf Karch Johann Stanek Thomas Wanek Wolfgang Wadsak Kurt Kletter Markus Müller Wolfgang L?scher Oliver Langer 《Journal of nuclear medicine》2008,49(8):1328-1335
The multidrug efflux transporter P-glycoprotein (P-gp) is expressed in high concentrations at the blood-brain barrier (BBB) and is believed to be implicated in resistance to central nervous system drugs. We used small-animal PET and (R)-11C-verapamil together with tariquidar, a new-generation P-gp modulator, to study the functional activity of P-gp at the BBB of rats. To enable a comparison with human PET data, we performed kinetic modeling to estimate the rate constants of radiotracer transport across the rat BBB. METHODS: A group of 7 Wistar Unilever rats underwent paired (R)-11C-verapamil PET scans at an interval of 3 h: 1 baseline scan and 1 scan after intravenous injection of tariquidar (15 mg/kg, n = 5) or vehicle (n = 2). RESULTS: After tariquidar administration, the distribution volume (DV) of (R)-11C-verapamil was 12-fold higher than baseline (3.68 +/- 0.81 vs. 0.30 +/- 0.08; P = 0.0007, paired t test), whereas the DVs were essentially the same when only vehicle was administered. The increase in DV could be attributed mainly to an increased influx rate constant (K1) of (R)-11C-verapamil into the brain, which was about 8-fold higher after tariquidar. A dose-response assessment with tariquidar provided an estimated half-maximum effect dose of 8.4 +/- 9.5 mg/kg. CONCLUSION: Our data demonstrate that (R)-11C-verapamil PET combined with tariquidar administration is a promising approach to measure P-gp function at the BBB. 相似文献