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43.
Proteomic and postproteomic characterization of keratan sulfate-glycanated isoforms of thyroglobulin and transferrin uniquely elaborated by papillary thyroid carcinomas 总被引:2,自引:0,他引:2
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Magro G Perissinotto D Schiappacassi M Goletz S Otto A Müller EC Bisceglia M Brown G Ellis T Grasso S Colombatti A Perris R 《The American journal of pathology》2003,163(1):183-196
Previous studies have suggested that surface components of papillary thyroid carcinoma (PTC) cells may be aberrantly glycanated, but the precise nature of these molecules has not been unveiled nor documented to be of clinical relevance. A monoclonal antibody was raised against a unique keratan sulfate (KS) determinant and used to differentially screen benign and malignant thyroid tissue for the expression of components carrying these moieties. In a total of 349 cases of benign and malignant thyroid lesions, 100% of the 115 PTC cases examined (including various histological subtypes) were found to contain KS-bearing molecules, whereas these were virtually absent from benign tissues and other thyroid tumors, with the exception of 21% of the follicular carcinoma cases analyzed. A composite immunoaffinity chromatography, immunochemistry, and mass spectrometric approach revealed that the PTC-specific KS-bearing macromolecules were unique glycoforms of thyroglobulin and transferrin. Combined, reciprocal immunoprecipitation and Western blotting further indicated that the former glycoform predominated and that most of the transferrin produced by PTC was glycanated with KS moieties. Fluorescent keratanase II-based fingerprinting of the KS moieties bound to these isoforms further demonstrated several PTC-specific peculiarities: 1) that a considerable portion of the moieties was covalently attached via a novel core protein linkage structure; 2) they had an unusual extended average length; 3) an unusual relative ratio of highly sulfated disaccharides terminating with alpha (2-3)-linked N-acetylneuraminic acid capping residues; and 4) a novel unidentified oligosaccharide moiety at the nonreducing terminus. Comparative analysis of the relative distribution of transferrin in benign versus PTC tissues highlighted a marked malignancy-associated abundance of the molecule, with a >75% frequency in expression in PTC. These findings demonstrate that PTC cells synthesize unique post-translationally modified thyroglobulin and transferrin variants in situ that may be directly exploitable for diagnosis, through histological and noninvasive cytological procedures; for devising novel strategies for antibody-guided imaging of this tumor in vivo; and for postsurgery follow-up of PTC patients. 相似文献
44.
Histopathological grading of soft tissue tumours. Prognostic significance in a prospective study of 278 consecutive cases 总被引:1,自引:0,他引:1
Olaf Myhre Jensen Jrgen Hgh Svend E.
stgaard Axel Munck Nordentoft Otto Sneppen 《The Journal of pathology》1991,163(1):19-24
A consecutive 10-year series of 278 soft tissue sarcomas was prospectively graded, using a system based on the number of mitoses and taking into account parameters such as cellularity, anaplasia, necrosis, and histogenetic type and subtype of tumour. Prognostic factors in relation to metastasis-free survival were studied by uni- and multivariate analysis. Fifty-seven (20.5 per cent) were low-grade tumours, 43 (15.5 per cent) were intermediate, and 178 (64 per cent) were high grade. High-grade tumours were divided into two groups; 80 (29 per cent) grade 3A (= 5-20 mitoses per 10 high power fields (HPF)) and 78 grade 3B (28 per cent) (= more than 20 mitoses/10 HPF); 10 HPF corresponds to 2.5 mm2. Twenty (7.2 per cent) high-grade tumours could not be further subdivided. Grading was found to be the prognostic factor associated with the strongest predictive value. Five-year survival in low-grade and intermediate tumours (95 and 86 percent, respectively) differed significantly (P less than 0.0001) from high grade (50 per cent) and (p = 0.0018) between grade 3A (64 per cent) and grade 3B (41 per cent). Other prognostic indicators of importance in high-grade tumours were age, local recurrence at presentation (primary operation outside the Centre), and localization (superficial vs. deep). 相似文献
45.
Administration of transforming growth factor-alpha enhances anatomical and behavioral recovery following olfactory nerve transection 总被引:3,自引:0,他引:3
Although replacement of olfactory receptor neurons (ORNs) and subsequent reinnervation of the olfactory bulb occur following ORN injury, the intrinsic and extrinsic factors that contribute to the regulation of this dynamic process have not yet been fully identified. Recent research indicates that several growth factors have neurogenic effects on ORNs in vitro, and that chronic in vivo administration of either basic fibroblast growth factor, epidermal growth factor, or transforming growth factor-alpha (TGF-alpha) following chemical lesion can enhance the normal rate of ORN reinnervation of the olfactory bulb. The primary goal of the present experiments was to further assess the extent to which growth factor-related enhancements in the rate of anatomical recovery during ORN reconstitution and subsequent reinnervation of olfactory bulb are accompanied by enhancements in the rate of recovery of odor-guided behavior.A series of experiments in rats was conducted to initially characterize the time course of the anatomical and behavioral recovery normally observed following ORN reconstitution as a consequence of olfactory nerve transection, and to subsequently characterize the anatomical and behavioral effects of TGF-alpha administration on this normal rate of recovery. Consistent with a host of prior studies, olfactory nerve transection produced consistent and substantial deafferentation of olfactory bulb followed by a time-dependent anatomical recovery which was significantly enhanced by administration of TGF-alpha. The effect of TGF-alpha on functional recovery following olfactory nerve transection was also assessed using an odor-guided fear conditioning task. ORN lesioned animals receiving injections of TGF-alpha during recovery were found to display enhanced conditioned responding to an olfactory stimulus compared to untreated subjects. Further behavioral analyses suggested that this enhanced functional recovery was likely not due to non-specific effects of TGF-alpha on cognition or motor activity, but rather to enhanced olfactory input to the CNS.Future studies will likely reveal the exact mechanism of action mediating the anatomical and concomitant behavioral effects of this growth factor. Since ORNs are one of only a few populations of neurons capable of regeneration or replacement, the continued study of the cellular and molecular factors that coordinate this regenerative process may ultimately lead to the development of therapeutic strategies to promote an enhanced functional recovery following injury to other neuronal populations. 相似文献
46.
Otto Braun-Falco Dr. Hans Christian Korting Birger Konz 《Virchows Archiv : an international journal of pathology》1981,393(1):115-121
Summary Although cryostat sections in general allow a distinction to be made between malignant melanomas and other pigmented lesions in clinically doubtful cases, the differential diagnosis may be difficult. The histological and cytological criteria taken into account can be classified as major, minor, and insufficient. Knowing the diagnostic value of each makes a conventionally established diagnosis safer. Variance analysis does not contribute to the problem but it can nevertheless be shown that the evaluation of six major criteria makes a quick and reliable cryostat section diagnosis possible. If these results are confirmed in a prospective study it would be a decisive step on the way to a quicker and safer cryostat section diagnosis of malignant melanoma, even for the less experienced histopathologist.The results published here were presented in part at the DDG meeting 1980 at Westerland/SyltWe are grateful to Miss Schubert, Institute of Biomathematics of the University of Munich, for the statistical evaluations 相似文献
47.
Mark H. Pollack Michael W. Otto Gary S. Sachs Andrew Leon M. Katherine Shear Joseph A. Deltito Martin B. Keller Jerrold F. Rosenbaum 《Journal of affective disorders》1994,30(4):273-281
This study examines clinical predictors of outcome for patients with panic disorder and depression in a 16 week, placebo-controlled trial of alprazolam and imipramine (n = 126). Baseline global severity of illness and phobic avoidance were differentially predictive of acute response to treatment. Patients in the mild to moderate range of global distress experienced smaller degrees of improvement on alprazolam than on imipramine at week 4. At endpoint, the relative effectiveness of the active medication versus placebo was diminished in patients with higher levels of phobic avoidance. This relationship was not evident for completers, suggesting that the adverse effects of avoidance on outcome after sustained treatment was reduced. 相似文献
48.
M J Radin K A Eaton S Krakowka D R Morgan A Lee G Otto J Fox 《Infection and immunity》1990,58(8):2606-2612
Establishment of infection with Helicobacter pylori and gastritis in nonhuman species is currently only successful in gnotobiotic piglets. This study was designed to determine whether H. pylori will colonize the gastrointestinal tract of gnotobiotic dogs. Gnotobiotic beagle pups were derived by standard methods. Group A (five dogs) was orally challenged with 3 x 10(8) H. pylori at 7 days of age. Group B (two dogs) received only peptone water but was contact-exposed beginning on day 23 postinfection (p.i.). Necropsy was performed on dogs on day 30 p.i. H. pylori colonized the stomach of all dogs (groups A and B). Urease map analysis correlated with the microbiologic findings and indicated that the density of colonization was less than that observed in human tissue. Organisms were also recovered from the pharynx, esophagus, duodenum, and rectum of 1, 2, 2, and 1 dog, respectively. All group A and one group B dog developed serum immunoglobulin G specific for H. pylori by day 30 p.i. Gross lesions were restricted to the stomach and consisted of small (less than 1 mm) lymphoid follicles. Microscopically, there were focal to diffuse lymphoplasmacytic infiltrates with follicle formation and mild to moderate infiltration of neutrophils and eosinophils in the gastric lamina propria. With the Warthin-Starry silver stain, organisms were seen on the surface of the gastric epithelial cells, beneath the mucus layer. We conclude that H. pylori colonizes the stomachs of gnotobiotic dogs for at least 1 month and the lesions resemble those seen in humans. H. pylori is transmissible by contact from infected to noninfected dogs. 相似文献
49.
Wolf Singer Ernst Pöppel Otto Creutzfeldt 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1972,14(2):210-226
Summary Spike activities of optic tract fibers and corresponding relay cells were recorded simultaneously in layers A and A1 of the dorsal lateral geniculate nucleus of the cat. Light stimuli of various diameters were shone into the receptive field center of these unit pairs and their input/output ratios were determined. An increase of the stimulus size leads to an impairment of the input/output ratio in on-center and off-center relay cells. This suppressive effect has approximately the same latency as the excitatory response.Intracellular recordings suggest that the inhibitory effect of the surround is due to a postsynaptic process. Inhibitory postsynaptic potentials occur during and — under certain stimulus conditions —before the excitatory response. The short latency of these IPSPs suggests that they result from the activity of adjacent units with the same RF characteristics as the recorded neuron. This inhibitory input is not restricted to the RF periphery but may also be activated by stimulation within the RF center. Most neurons are also inhibited by units with antagonistic center responses.During the period of this research Ernst Pöppel held a training grant of the Stiftung Volkswagenwerk, Az. 11 1015. 相似文献
50.
The relationship between semantic organization and memory in obsessive-compulsive disorder 总被引:4,自引:0,他引:4
Deckersbach T Otto MW Savage CR Baer L Jenike MA 《Psychotherapy and psychosomatics》2000,69(2):101-107
BACKGROUND: A variety of evidence suggests that frontostriatal dysfunction is involved in obsessive-compulsive disorder (OCD). This evidence includes both neuroimaging findings and results from studies using neuropsychological assessments. Previous studies have documented nonverbal memory deficits in individuals with OCD, whereas verbal learning and memory were less affected. METHODS: The present study examined both verbal and nonverbal memory in a sample of 17 untreated outpatients with OCD. We also evaluated the effects of encoding strategies which are believed to be mediated by frontostriatal system functioning. RESULTS: OCD patients were significantly impaired in both verbal and nonverbal memory performance. This deficit was correlated with impairments in organizational and semantic clustering strategies at the time of encoding. CONCLUSIONS: Deficits in organizational strategies are consistent with frontostriatal dysfunction models in OCD. 相似文献