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1.
We present four head and neck cancer patients who apparently had rapid progression of clinically occult disease during or soon after undergoing hyperbaric oxygenation. This led us to review existing knowledge about the interaction of HBO with tumors. The literature can be summarized as follows: 1. HBO is a useful tool in several situations commonly encountered by head and neck surgeons-infections, radionecrosis, and wound-healing problems. 2. The use of HBO as a hypoxic cell sensitizer during radiation therapy has been extensively studied, with evidence supporting only marginal advantage to this logistically difficult undertaking. 3. Most reports regarding the interaction of HBO with transplanted tumor cells suggest no effect on tumor growth or metastases. 4. Studies of chemically induced carcinogenesis are less conclusive. Some evidence supports a role for HBO in enhancing growth of preexisting tumors. Better understanding of the interaction of HBO with existing tumors is required to ensure that informed choices-weighing potential risks and benefits of HBO treatment--may be made by head and neck surgeons and their patients. Further research into the interaction between HBO and tumor cells is warranted.  相似文献   

2.
BACKGROUND: The main purpose of this study was to determine the prevalence of human papillomavirus (HPV) infection in patients with head and neck carcinomas from Brazil. MATERIALS AND METHODS: Forty-five patients with head and neck squamous cell carcinoma were included in the study, from 1995 to 1996. Forty-two were male and 3 female, with age ranging from 32 to 82 years (median 61). Five patients (11%) did not have previous history of use of tobacco and 38 (90.5%) were heavy smokers. Tumor sites were pyriform sinus, 10; tongue, 11 (oral, 6; base, 5); larynx, 7; floor of mouth, 3; tonsil, 6; retromolar area, 3; inferior gingiva 2; buccal mucosa, 2; and maxillary sinus in 1 patient. Twenty-five were stage IV, 17 stage III, and 3 stage II. RESULTS: The presence of HPV DNA was detected in 5 of 45 patients (11%), all of them with HPV 16. Two patients had HPV DNA in normal mucosa and tumor tissue, 1 patient had HPV DNA only in the normal mucosa and tumor tissue, 1 patient had HPV DNA only in the normal mucosa, and 2 patients were positive for HPV DNA in tumor tissue. Four patients were male and 1 was female; 2 patients were nonsmokers. Three patients had tonsil carcinoma, 1 patient had a tongue carcinoma, and 1 patient had a pyriform sinus cancer. CONCLUSIONS: The role of chemical carcinogens seems to be more important in the genesis of head and neck cancer than is HPV infection. The presence of HPV DNA in 5 of 45 patients stimulates further investigation to determine the role of HPV as a risk factor for head and neck carcinoma.  相似文献   

3.
Fibronectin expression and distribution were examined in cancer tissues from 19 patients with cancer of the head and neck regions. Samples taken before and after irradiation of approximately 10 Gy, 20 Gy or 30 Gy were analyzed by the avidin-biotin-horseradish peroxidase method using mouse monoclonal antibodies against human fibronectin. The results were correlated with the patient's prognosis after radiation therapy. No remarkable changes in the fibronectin expression or distribution were found between tissue specimens taken before and after each dose of irradiation. The prognosis, however, varied according to the degree of expression and the distribution pattern of fibronectin. Seven patients in which the cancer tissue was encircled by a thick fibronectin network are still alive without recurrence 4.5-6 years after treatment, whereas 6 patients in which fibronectin was only faintly expressed or focally distributed died or developed recurrence soon after treatment. The present findings demonstrate that fibronectin expression and distribution in cancer tissue are intimately related to the patient's prognosis, and that the analysis of these two parameters is applicable as a predictive assay in radiotherapy of cancer of the head and neck regions.  相似文献   

4.
BACKGROUND: A strong positive correlation exists between the breast cancer tissue content of either urokinase-plasminogen activator (uPA) or plasminogen activator, inhibitor type I (PAI-1), quantified in the tissue extracts by immunoassays, and the survival of patients with breast cancer. Furthermore, several studies assign to the urokinase-type plasminogen activator receptor (uPAR) a pivotal role in triggering the proteolytic activity of the urokinase pathway involved in tumor stroma degradation, tumor spread and metastasis. However, the pattern of distribution of uPAR in normal and cancerous human tissue and the pattern of coexpression of activators and inhibitors that occurs in breast cancer tissues is not completely known. METHODS: The immunohistochemical localization of uPAR, uPA, tPA) and PAI-1 was evaluated by using the avidin-biotin immunoperoxidase technique and affinity-purified monoclonal antibodies from American Diagnostica Inc. Studies were performed in formalin fixed, paraffin-embedded tissue prepared from 23 surgically excised non-neoplastic breast tissues and 18 ductal breast carcinomas. RESULTS: While the expression of uPAR protein represents a constant feature of invasive ductal breast cancer, it was also observed in most of the breast tissue samples, including the normal breast tissues. The staining for uPAR was mainly localized on normal or tumoral epithelial cells, even if the co-expression of uPAR in stromal cells was frequently observed in adjacent slides. A semiquantitative analysis of immunohistochemical results showed that uPAR and PAI-1 were overexpressed in invasive breast cancer in comparison with normal and benign breast tissues. In addition, uPA was higher in both invasive breast carcinomas and benign breast lesions with respect to normal breast tissues. CONCLUSIONS: We showed that overexpression of uPAR, uPA, and its main inhibitor, PAI-1, is a constant feature of invasive ductal breast carcinomas. However, the expression of the above fibrinolytic reactants is not specific for breast cancer since positive staining for these molecules was frequently observed in benign breast lesions as well as in normal breast tissues. The combined increased expression of uPA and its cellular receptor, uPAR on the surface of tumor epithelial cells may account for the activation of the proteolytic system which occurs in breast cancer.  相似文献   

5.
Individuals who have received head and neck radiation for benign conditions have a markedly increased risk of developing thyroid, salivary, and perhaps breast cancer as compared to the general population. Although the relative risk is very high, the absolute risk that any one individual who has had head or neck irradiation will develop a subsequent malignancy is low. Identification of these patients through some type of screening procedure may be beneficial in terms of prevention of subsequent morbidity and perhaps mortality from cancer, especially thyroid and salivary cancer. The risks of any detection or prophylaxis program must be carefully weighed against the probable, but unproved benefits of early detection. A major unresolved question is the natural history of microscopic thyroid carcinoma in the 25 yr-40 yr old radiation exposed population.  相似文献   

6.
BACKGROUND: Tumor hypoxia could play a role in the response to radiation therapy. Few data are available on oxygen tension (pO2) measurements in head and neck tumors. METHODS: The KIMOC-6650 Histograph (Eppendorf, Hamburg, Germany) was used to measure the oxygenation status of normal tissues and head and neck tumors in 20 patients. RESULTS: The median pO2 for normal tissues was 43 mmHg with very low pO2 values (2.0 mmHg or less) recorded in two patients. Low median pO2 levels (10 mmHg or less) were recorded in 2 of 5 primary tumors and in 11 of 15 metastatic lymphadenopathies, with very low values in 11 nodes. The median pO2 in tumors was lower than that of normal tissues in 12 of 15 patients with comparative measurements. Oxygen tension was recorded in three nodes after an evaluation of tissue density (by computed tomographic scanner); in two nodes, the mean and median pO2 values were lower in the hypodense areas than in isodense areas. The data for N2 and N3 nodes showed significantly more values below 2.0 mmHg as nodal size increased (P < 10(-4), by chi-square test). No systematic decrease in pO2 was recorded from the periphery to the center of the tumors. CONCLUSIONS: Very low pO2 values, corresponding to radiobiologic hypoxia, were found in most of these tumors. The prognostic value of these pO2 measurements in regard to treatment response remains to be demonstrated.  相似文献   

7.
Lysosomal cysteine proteinases, the cathepsins (Cats) belong to the papain family of proteinases, sharing a similar protein structure and mechanism of action. Subtle structural differences between these enzymes give rise to important variations in substrate specificity and specificity of inhibition by their endogenous inhibitors, the cystatins, stefins and kininogens under physiological and pathological conditions. Alterations in their expression, processing and localization have been observed at various levels in malignant human tumor tissue compared to normal and benign tissue counterparts. We have proposed that an imbalance between cathepsins and cystatins, associated with metastatic tumor cell phenotype, may facilitate tumor cell invasion and metastasis. The results of clinical investigations on cysteine cathepsins and their endogenous inhibitors in human breast, lung, brain and head and neck tumors, as well as in body fluids of ovarian, uterine, melanoma and colorectal carcinoma bearing patients, have shown that these molecules are highly predictive for the length of survival and may be used for assessment of risk of relapse and death for cancer patients. Their application for diagnosis, follow-up and the anticancer therapy has also been proposed.  相似文献   

8.
OBJECTIVE: To evaluate the clinical potential of fluorescence spectroscopy (a noninvasive technique for assessing the chemical and morphologic composition of tissue) for in vivo detection of oral cavity neoplasia. DESIGN: A fluorescence spectroscopy system recorded spectra from oral cavity sites in 8 healthy volunteers and in 15 patients with premalignant or malignant oral cavity lesions at 337-, 365-, and 410-nm excitation wavelengths in the emission range of 350 to 700 nm. Fluorescence peak intensities and spectral line shapes were compared and diagnostic algorithms were developed to distinguish normal sites from abnormal sites. SETTING: The head and neck cancer clinic at a tertiary referral center in Houston, Tex. RESULTS: Differences were found in spectra from normal, dysplastic, and malignant oral mucosa. The fluorescence intensity of normal mucosa was greater than that of abnormal areas. In addition, the ratio of red region (635-nm) to blue region (455-490-nm) intensities was greater in abnormal areas. Diagnostic discrimination was achieved when test site spectra were compared with spectra from a normal site in the same patient. One diagnostic algorithm based on spectra at 337 nm gave a sensitivity of 88% and a specificity of 100%. CONCLUSIONS: Consistent differences exist between the fluorescence spectra of abnormal and normal oral mucosa. Therefore, fluorescence spectroscopy has the potential to improve the noninvasive diagnosis of oral cavity neoplasia. Further studies will better define the role of this technique in the detection of premalignant and early oral cancer lesions.  相似文献   

9.
Between 1996 and 1997 serum and urine levels of basic fibroblast growth factor (b-FGF) in patients with head and neck cancer were measured to answer the following questions: i) Are increased levels of b-FGF in serum and urine detectable in patients with malignant head and neck tumors? ii) Do these parameters correlate with tumor stage and differentiation of tumors? iii) Is there an association between growth behaviour (local or metastatic growth) and b-FGF levels in serum and/or urine? Eighty-nine patients with head and neck cancer as well as 45 patients with diseases unrelated to cancer were investigated. Detectable levels of b-FGF were found in the serum and urine of patients with malignant head and neck tumors. In addition, there was a significant correlation between tumor size and b-FGF levels in either serum or urine. No association of b-FGF concentrations with degree of histologic differentiation and tumor growth behaviour was observed. The results of this study demonstrate that b-FGF levels are elevated in serum and urine of patients with head and neck cancer. These findings suggest an involvement of b-FGF in the formation of solid tumors.  相似文献   

10.
BACKGROUND: Whether or not tumor response to chemotherapy-sensitized radiation therapy (CTRT) for head and neck cancer leads to an improved outcome is unknown. METHODS: Forty patients who received preoperative cisplatin plus simultaneous radiotherapy for operable stage III and IV head and neck cancer were reviewed retrospectively regarding clinical demographics, staging, and survival status. RESULTS: Twenty-one (57%) patients had a histologic complete response (HCR) and 16 (43%) had a partial (PR) (9) or clinical complete (7) response (CCR). Tumor response of N1 versus N2-3 nodal disease showed 6 (75%) HCR and 4 (25%). Five-year disease-free survival overall was 82% for HCR versus 38% for PR/CCR (P <0.05). Disease-specific 5-year survival was 100% for HCR versus 27% for PR/CCR (P <0.002). CONCLUSIONS: Histologic complete response to CTRT for head and neck cancer is associated with increased survival and encouraging disease-free status. Response to CTRT is inversely proportional to lymphatic tumor load.  相似文献   

11.
PURPOSE: To determine the ability of in vitro one-dimensional and two-dimensional proton MR spectroscopy to help differentiate squamous cell carcinoma of the extracranial head and neck from normal tissues and to correlate the in vitro observations with clinical studies. METHODS: In vitro 1-D and 2-D correlated proton MR spectroscopy (11 T) was performed in tissue specimens of squamous cell carcinoma of the head and neck (n = 19), in normal tissue (n = 13), in metastatic cervical lymph nodes (n = 3), and in a squamous cell carcinoma cell line. In vivo 1-D proton MR spectroscopy (1.5 T) was performed in patients with squamous cell carcinoma (n = 7) and in healthy volunteers (n = 7). The ratio of the areas under the choline (Cho) and creatine (Cr) resonances were calculated for 1-D proton MR spectra for the in vitro tissue studies and correlated with the in vivo studies. Data from in vitro 2-D correlated spectroscopy were analyzed for differences in the presence or absence of various metabolites in samples of tumor and normal tissue. Statistical analysis consisted of 2 x 2 factorial repeated measures analysis of variance (ANOVA), discriminate analysis, and chi2 test. RESULTS: The mean in vitro 1-D proton MR spectroscopic Cho/Cr ratio was significantly higher in tumor than in normal tissue. The difference between the mean ratios appeared to increase with increasing echo time. All in vivo tumor Cho/Cr ratios were greater than the calculated mean in vitro tumor ratio, whereas six of the seven volunteers had no detectable Cho and Cr resonances. Two-dimensional correlated MR spectroscopic data revealed that a variety of amino acids have a significantly greater likelihood of being detected in tumor than in normal tissues. CONCLUSIONS: One-dimensional and 2-D proton MR spectroscopy can help differentiate primary squamous cell carcinoma and nodal metastases containing squamous cell carcinoma from normal tissue both in vitro and in vivo. In addition, 2-D spectroscopy can help identify the presence of certain amino acids in squamous cell carcinoma that are not detected in normal tissue.  相似文献   

12.
BACKGROUND: The aim of photodynamic diagnosis (PDD) is the complete visualization of all neoplastic lesions in a tumorous organ after topical or systemic application of a tumor selective photosensitizer. In this investigation we performed semiquantitative fluorescence measurements following topical application of 5-aminolevulinic acid (5-ALA) in 11 patients with neoplastic lesions of the oral cavity. METHODS: Time course and type of porphyrin accumulation were analyzed in neoplastic and surrounding normal tissue by measuring emission spectra of 5-ALA-induced protoporphyrin IX (PpIX) fluorescence at regular intervals for up to three hours following 15 min continuous rinsing of a 0.4% 5-ALA solution. After excitation with violet light of a high pressure xenon arc lamp (375-440 nm), fluorescence images in the red spectral range from the tumor tissue and the corresponding macroscopic visible tumor were recorded with a CCD camera. A quantitative analysis of the fluorescence contrast in neoplastic and surrounding tissue was performed using an optical multichannel analyzer. RESULTS: PpIX fluorescence was detected in the oral mucosa of all patients after local application of 5-ALA. PpIX in neoplastic tissue accumulated earlier in comparison to the surrounding normal tissue. The fluorescence contrast between tumor and host tissue was 10:1 and the maximum fluorescence was measured 1-2 hours following 5-ALA application. CONCLUSION: Labeling of mucosal lesions of the oral cavity with PpIX fluorescence induced by the local application of 5-ALA seems to be a promising diagnostic procedure for neoplastic lesions. Further investigations are required to assess the value of this new diagnostic procedure as a non-invasive and sensitive method for patients with head and neck cancer not only in pre- and postoperative diagnostic studies but also for a fluorescence-guided resection of tumors.  相似文献   

13.
Thyroid function may be reduced after treatment of cancer of the head and neck, and hypothyroidism is much more common after combination therapy. Whether hypoparathyroidism and subsequent hypocalcemia also occur after such treatment is unknown. Few related studies have been published in which changes in total serum calcium have been studied after cancer treatment with radioactive iodine or external radiation. Twenty-two disease-free head and neck cancer patients were studied, 1 to 3 years after multimodal treatment, to determine if changes in serum ionized calcium levels or thyroid function were present. Our results suggest that parathyroid function, as represented by ionized calcium levels remains normal after multimodality (surgery, radiation and/or chemotherapy) combined treatment.  相似文献   

14.
In vitro models are currently being used to study head and neck squamous cell carcinoma (HNSCC). Several hundred HNSCC cell lines have been established by various investigators and used to study a broad spectrum of questions related to head and neck cancer. The head and neck model with respect to multistage carcinogenesis is now complete. Several techniques exist for the culture of normal epithelial cells from the upper aerodigestive tract (UADT). The biology of these UADT cells (oral cavity, oropharynx, hypopharynx and larynx) is being studied. Successful culture of premalignant lesions (dysplastic mucosa, leukoplakia, erythroplakia) has resulted in establishment of a limited number of premalignant cell lines and cell cultures. HPV infection of normal oral epithelial cells for immortalization (approximately premalignant cells) coupled with transformation with carcinogens (malignant cells) has established an experimental model for progression. Two in vivo models for oral carcinogenesis, the 7,12 dimethylbenz(a)anthracene-induced hamster cheek pouch model and the 4-nitroquinoline-N-oxide rat oral model, have been established in culture. Thus, multistage carcinogenesis models have been established from both human tissues and animal models and include cultures of normal, premalignant and malignant cells. Culture techniques for growing dissociated primary tumor cells for short term experimental analysis are being used. The culture of normal or tumor tissue as organ/explant cultures allows for the maintenance of normal cell-cell and cell-matrix interaction, but limits experimentation since these cultures cannot be propagated. Several three dimensional model systems are being used to obtain this histological complexity but allow for experimentation. The ability to culture normal, premalignant and malignant cells coupled with the use of a variety of culture techniques, should allow for the continued growth and experimentation in head and neck cancer research.  相似文献   

15.
AIM: This study evaluates F-18-FDG PET of the thyroid in Graves' disease. METHODS: Thirty patients were investigated the day before radioiodine therapy, 15 patients 3-10 days after radioiodine therapy. Twenty patients with cancer of the head or neck and normal thyroid function served as controls. RESULTS: F-18-FDG uptake was higher in Graves' disease patients than in controls. Negative correlations of F-18-FDG uptake with half-life of radioiodine and absorbed radiation dose due to radioiodine therapy were found along with a positive correlation to autoantibody levels. CONCLUSION: Thus F-18-FDG PET is likely to give information on the biological activity of Graves' disease as well as on early radiation effects.  相似文献   

16.
The in vitro radiosensitivity of dermal fibroblasts has been found to vary between individuals, and a number of studies have also shown that this parameter correlates with radiation-induced late injuries in clinical radiotherapy. In addition, certain genetic disorders are known to effect radiosensitivity, e.g. normal tissues of patients homozygous or heterozygous for the ataxia teleangiectasia gene show unusual sensitivity to radiation both in vivo and in vitro. Thus, it has been assumed that there is a genetically determined component resulting in a certain intrinsic cellular radiation response in an individual. To study this possible relationship between different cells of a specific patient, we established eight pairs of dermal and tumor fibroblast cultures. The donor patients had either adenocarcinoma of the uterus or squamous cell carcinoma (SCC) of the head and neck. The radiosensitivity of these strains was determined by a 96-well plate clonogenic assay, previously used by us for radiosensitivity testing of cancer cells. From a paired comparison, the values for the cell fraction surviving 2.0 Gy (SF2), of both fibroblast strains, were found to be on the same level in five out of eight cases. In patient 6, the SF2 of tumor fibroblasts was significantly higher than that of dermal fibroblasts (P=0.0014). In two additional cases the tendency was the same, but not statistically significant. As groups, the two types of fibroblasts did not differ from each other, mean SF2 values of 0.24+/-0.07 and 0.21+/-0.05, respectively. The SF2 of tumor fibroblasts from SCC patients proved to be significantly higher than that of the adenocarcinoma patients (P=0.030). These preliminary results indicate that the in vitro radiosensitivity of tumor fibroblasts correlates with normal cell sensitivity in many cases, but not in all. The radiosensitivity of tumor fibroblasts also seems to follow the level of in vitro radiosensitivity determined for the corresponding histological type of tumor cells. Further studies are needed to determine more closely the relationship between the radiosensitivities of tumor cells and tumor fibroblasts, thus evaluating the possibility of testing radiosensitivity from tumor fibroblasts in order to estimate tumor response.  相似文献   

17.
PURPOSE: To evaluate indium 111 octreotide scintigraphy for the detection of suspected neuroendocrine lesions of the head and neck. METHODS: After receiving 6 mCi of 111In octreotide, 22 patients with suspected lesions of the head and neck were examined with both planar and single-photon emission CT (SPECT). Static images, obtained at 4 hours, included the head/neck, chest, abdomen, and pelvis. Additional SPECT images were obtained at 4 or 24 hours. Studies were compared with available conventional radiologic examinations (12 CT, 11 MR, and three angiographic studies) as well as with clinical and pathologic findings. RESULTS: Eighteen of the 22 patients had abnormal findings at scintigraphy. Eleven paragangliomas were seen in 10 patients, metastatic medullary thyroid carcinoma in three patients, thyroid adenoma in two patients, and Merkel cell tumor, carcinoid, and plasmacytoma in one patient each. Surgical confirmation was available in 13 patients. The smallest lesion detected was 1.5 cm. There was one false-positive and one false-negative examination. CONCLUSION: 111In octreotide scintigraphy is a useful imaging tool for the detection of primary and metastatic neuroendocrine tumors of the head and neck that are larger than 1.5 cm. This technique enables distinction of glomus tumors from other masses (such as neuromas) and can be used in the postoperative setting to distinguish scar from recurrent paraganglioma. Since it is an examination of the entire body, it has great utility for detecting multicentric paraganglioma and for screening patients with familial paraganglioma.  相似文献   

18.
There are critical maximum temperatures above which irreversible damage occurs in cells and tissues. Exposure to high temperature, referred to as hyperthermia (HT), can result in cell death, tissue damage or even death of the organism. Clinical application of HT as a primary treatment or as an adjuvant to radio-/chemo- therapy of cancer is based on its ability to cause localized tumor tissue damage. Experimental data provide HT with a strong biological rationale. Early clinical experience suggested that HT will become an important modality as an adjuvant to radiotherapy in the treatment of human malignancies, but its application is currently limited to mainly superficial tumors. Its full realization as a treatment modality for cancer therapy awaits further laboratory investigations as well as controlled clinical trials. A better understanding of the biological mechanisms of its action, interaction with chemotherapeutic drugs and radiation damage, role of tumor microenvironment such as oxygen status and pH of tumors, and kinetics of thermotolerance can lead to refinement in its clinical implementation. The present review attempts to analyse the published literature during the last one and half decades.  相似文献   

19.
Intraoperative radiotherapy is a technique that can be integrated into multidisciplinary treatment strategies in oncology. A radiation boost delivered with high energy electron beams can intensify locoregional antitumor therapy in patients undergoing cancer surgery. Intraoperative radiotherapy can increase the therapeutic index of the conventional combination of surgery and radiotherapy by improving the precision of radiation dose location, while decreasing the normal tissue damage in mobile structures and enhancing the biological effect of radiation when combined with surgical debulking. Intraoperative radiotherapy has been extensively investigated in clinical oncology in the last 15 years. Commercially available linear accelerators require minimal changes to be suitable for intraoperative radiotherapy. Its successful implementation in clinical protocols depends on the support given by the single institutions and on a clinical research-oriented mentality. Tumors where intraoperative radiotherapy as a treatment component has shown promising rates of local control include locally advanced rectal, gastric and gynecologic cancer, bone and soft tissue sarcoma. Intraoperative radiotherapy can be applied to brain tumors, head and neck cancer, NSCLC and pancreatic carcinoma.  相似文献   

20.
In an attempt to improve local control of locally advanced head and neck cancer, radiation therapy was combined with cisplatin. Forty-eight patients entered into this study. All patients were irradiated with a 60Co unit and according to the protocol they should receive 70 Gy in the tumor area and 45 Gy in the rest of neck. Cisplatin was administered at a dose of 100 mg/m2 on days 2, 22 and 42. Thirty-seven (80%) patients received the total radiation dose as initially planned. Thirty-four (72%) patients achieved complete and 5 (10%) partial response. Grade 3-4 toxicities included vomiting (14%), stomatitis (4%), diarrhea (2%), myelotoxicity (14%), hoarseness (4%), dysphagia (30%), weight loss (32%), nephrotoxicity (4%) and dermatitis (2%). After a median follow-up of 26 (range, 18-33) months, 16 patients have died. Among the 35 complete responders 6 later on relapsed. Median relapse-free survival has not yet been reached. Combined radiation therapy and cisplatin appears to be a highly active treatment in patients with advanced head and neck cancer as far as primary locoregional response is concerned.  相似文献   

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