In vitro testing the potential of a novel chimeric IgG variant for inhibiting collagen fibrils formation in recurrent hereditary gingival fibromatosis: chimeric antibody in a gingival model.

Gingival fibromatosis is a progressive enlargement of the gingiva. It may hinder oral cavity hygiene and result in underlying bone loss. The long-term benefits of surgery cannot be predicted. On the other hand, alternative, efficient and non-invasive methods are not available at present. The aim of this study was to test the inhibitory effects of a chimeric IgG variant on collagen fibril formation in the cell culture of gingival fibroblasts taken from a patient with hereditary gingival fibromatosis with a high propensity for recurrence. Gingival biopsies were collected from the mandibular gingiva and used for histological evaluation as well as to establish a fibroblast culture. A histological evaluation was made in haematoxylin-eosin and Heidenhain's trichrome stained tissue sections. The inhibitory effect of a chimeric antibody on collagen fibril formation was determined in fibroblast cultures by using a collagen-specific Western blot and immunofluorescent staining. A histological evaluation revealed epithelial acanthosis with singular elongated rete pegs extending into the underlying connective tissue stroma that consisted of locally abundant, irregular collagen bundles. Based on observations with an in vitro model we conclude that a chimeric anti-collagen antibody efficiently inhibits collagen fibril accumulation in cell culture derived from diffuse, hereditary gingival fibromatosis that is characterized by a high propensity for recurrence (high proliferation index). Employing cell cultures from standardized group of patients with recurrent hereditary gingival fibromatosis as well as standarizing relevant 3D (tissue-like) models will be crucial for further tests of the antibody.

Influence of vascular endothelial growth factor (VEGF) on gastroprotection in stress-induced gastric mucosal ulcers in rats.

In the process of evolution a number of complicated mechanisms have developed to protect the gastric mucous membrane, e.g., angiogenesis and stimulation of mucosal growth. The aim of this study was to determine the role of vascular endothelial growth factor (VEGF) administered intraperitoneally in the gastroprotective response to stress-induced acute gastric ulcers in rats. A dramatic increase in the number of blood vessels was observed when VEGF was injected 24 h before stress exposure. Gastric secretion, depth of ulceration and ulceration index decreased significantly after VEGF application. The results demonstrate the gastroprotective effect of VEGF on stress-induced ulceration.

Unusual malignant thyroid tumours--a clinical study of 20 cases.

UNLABELLED: The aim of this study is to assess late results of surgical treatment for primary non-Hodgkin lymphoma (PNHL), thyroid sarcomas (TS) and tumour metastases (TM) of the thyroid gland. MATERIALS AND METHODS: Between January 1st, 1990 and December 31st, 2005, 12725 patients were surgically treated for various types of goitre. Malignant tumour was diagnosed in 617 (4.9%) cases, consisting of 597 (96.8%) patients with thyroid carcinoma and 20 (3.2%) with other tumours, which included 9 (1.5%) cases of PNHL, 9 (1.5%) cases of TM and 2 (0.2%) patients who showed TS. RESULTS: In the group of patients diagnosed with PNHL, variant B-cell lymphoma predominated (77.8%), and in cases of patients with TM renal cell carcinoma prevailed (77.8%). In all cases, hypo-echogenic nodules were observed in ultrasonography and cold nodules in scintigraphy. All patients were surgically treated with possible complementary chemotherapy and/or radiotherapy. At present, 5 patients with PNHL are alive--43-93 (average of 63.8) months after the operation. Others have died within a period of 2 days to 3 months after the operation. Two patients with TM are alive--19 and 46 (median 32.5) months after the operation. Others have died within a period of 3 to 62 (median 21) months after the operation. Patients with TS have died respectively 19 days and 13 months after the operation. CONCLUSIONS: 1. Patients with primary thyroid lymphomas should be approached individually using all available methods of treatment, including surgery and radiotherapy and/or chemotherapy. 2. Diagnosis of cold nodules in patients with oncological history should always arouse suspicion of metastases to the thyroid gland. 3. Diagnosis of non-thyroid cancer prior to surgery is difficult to obtain. 4. The need for surgery is usually based on local compression.

Dynamics of changes in vascular endothelial growth factor (VEGF) expression and angiogenesis in stress-induced gastric ulceration in rats.

Angiogenesis and VEGF play a major role in many repair processes such as healing of gastric ulceration. The present study was undertaken to assess the dynamics of changes in VEGF expression and angiogenesis in stress-induced gastric ulcers in rats. Acute gastric ulceration was induced using a water-immersion and restraint stress method. The VEGF expression, angiogenesis, size of area and depth of ulcers in gastric specimens were evaluated. The study shows that as early as one day after the development of ulcers there is a significant increase in both the expression of the VEGF protein and the number of newly formed microvessels, while an abrupt decrease in VEGF expression, observed on the fifth day, results in a decreased intensity of angiogenesis. Moreover, it has been demonstrated that the increase in VEGF expression and angiogenesis is accompanied by a reduction in the size of area and depth of stress-induced ulcers in rats. Six days after ulcer development both VEGF expression and angiogenesis return to normal levels.

Clinical application of proliferating cell nuclear antigen, oncoprotein p53 and tumor front grading analysis in patients operated on for laryngeal cancer.

The authors assessed proliferating cell nuclear antigen (PCNA), p-53 oncoprotein and morphologic tumor front grading (TFG) in patients with advanced squamous cell carcinoma (SCC), of the larynx and a poor prognosis and tried to find a correlation with tumor stage, the Broders grading system, local and neck lymph node metastases, as well as nodal and local recurrences. In addition, utility of the parameters investigated was evaluated in developing a prognostic factor model, using uni- and multivariate Cox regression analysis. Included in this study were 54 patients (mean age 57 years +/- 8.6). PCNA-positive staining was found in all but one patient with advanced disease, while p-53 stained positively in only 24 subjects (44.4%). The PCNA index ranged from 4.6 to 59.0% (mean, 23.4 +/- 11. 0) and the p-53 index varied from 4.0 to 42.0% (mean, 17.2 +/- 8.6). The TFG score ranged from 9 to 23 points (mean, 15.1 +/- 3.2). PCNA, p-53 and TFG were found to be the markers that provided significant additional information about the biological behavior of tumor cells. The high variability of the results (PCNA, p-53) and high percentage of negatively stained cells (p-53) reduced their application in clinical use. PCNA correlated with tumor grade, G (r = 0.38; P < 0. 01), but negatively with nodal (N) disease(r = -0.37; P < 0.01). The mean values of PCNA and p-53 index were higher in the subgroup with local recurrences. Our present attempt to develop a useful prognostic factor model failed.