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41.
Beasley MB Thunnissen FB Brambilla E Hasleton P Steele R Hammar SP Colby TV Sheppard M Shimosato Y Koss MN Falk R Travis WD 《Human pathology》2000,31(10):1255-1265
Pulmonary neuroendocrine tumors (NE) include a spectrum of tumors from typical carcinoid (TC) to atypical carcinoid (AC), large cell neuroendocrine carcinoma (LCNEC), and small cell carcinoma (SCLC). Little is known about prognostic predictors for AC because of its rarity. Survival analysis was performed on 106 ACs with clinical follow-up from the AFIP and the Pathology Panel of the International Association for the Study of Lung Cancer (IASLC). The tumors fulfilled the 1999 WHO/IASLC criteria for AC of a NE tumor with a mitotic rate of 2 to 10 per 2 mm(2) of viable tumor or coagulative necrosis. Multiple clinical and histologic features were analyzed by Kaplan-Meier and Cox regression analysis. Of the clinical features, higher stage (P = .003) and a tumor size of 3.5 cm or greater (P = .003) were associated with a worse prognosis. Features that were histologically unfavorable by univariate analysis were mitotic rate (P =.002), pleomorphism (P = .018), and aerogenous spread (P =.007). Histologically favorable features by univariate analysis were the presence of palisading (P = .008), papillary (P = .039), pseudoglandular (P =.026), and rosette (P = .022) patterns. Female gender showed a trend toward a poorer prognosis (P =.085) and was included in the multivariate model. Multivariate analysis stratified for stage showed mitoses (P<.001), a tumor size of 3.5 cm or greater (P =.017), and female gender (P =.012) to be the only negative independent predictors of prognosis and the presence of rosettes (P = .016) to be the only independent positive predictor. We further divided the AC into subgroups of low (2 to 5 mitoses/2 mm(2)) and high (6 to 10 mitoses/2 mm(2)) mitotic rate and compared the survival with TC and with LCNEC. Within the category of AC, the patients with a higher mitotic rate had a significantly worse survival than those with a lower mitotic rate (P<.001) stratified for stage. Five- and 10-year survival rates for AC (61% and 35%, respectively) stratified for stage were significantly worse than for TC and better than that for LCNEC and SCLC. Chemotherapy or radiation therapy was given in 12 of 52 and 14 of 52 cases, respectively, but the data were insufficient to evaluate tumor response. We conclude that AC is an aggressive neuroendocrine neoplasm with survival intermediate between TC and LCNEC and SCLC. Higher mitotic rate, tumor size of 3.5 cm or greater, female gender, and presence of rosettes are the only independent predictors of survival. Surgical resection remains the treatment of choice, and the role of chemotherapy and radiation therapy remains to be proven. 相似文献
42.
43.
Transforming growth factor-beta 1, 2, and 3 can inhibit epithelial tissue outgrowth on smooth and microgrooved substrates 总被引:1,自引:0,他引:1
Walboomers XF Dalton BA Evans MD Steele JG Jansen JA 《Journal of biomedical materials research》2002,60(3):445-451
In this study, we describe the influence of parallel surface microgrooves, and of TGF-beta, on the outgrowth of corneal epithelial tissue. Microgrooves (depth 1 microm, width 1-10 microm) were made in polystyrene culturing surfaces. These surfaces were left untreated, or loaded with TGF-beta 1, 2, or 3 (6.0 ng/cm(2)). Subsequently, epithelial explants from bovine corneas were placed on the experimental surfaces. After 9 days of culturing, tissue outgrowth was evaluated. Furthermore, the tissue cultures were analyzed histologically. It was shown that epithelial tissue grew from the explants over all experimental surfaces. On microgrooved surfaces outgrowth proceeded in the direction of the grooves, rather than perpendicular to the grooves. The addition of each type of TGF-beta resulted in a reduction of outgrowth. However, outgrowth remained directed by the grooves. Further, the explants had shrunk after TGF treatment. Histology showed that this shrinkage was not related to alpha-smooth muscle actin expression in the explants. We conclude that microgrooves can direct, and TGF-betas can inhibit the outgrowth of epithelial tissue. This finding could be useful in biomaterial applications where the growth of epithelial tissue needs to be discouraged. 相似文献
44.
The suitability of polymeric biomaterials as surfaces for the attachment and growth of cells has often been investigated in tissue culture. In this study the contribution that adsorption of serum fibronectin (Fn) or vitronectin (Vn) make to the attachment and spreading of fibroblast cells during the first 90 min following seeding was determined for two modified tissue culture polystyrenes, as model biomaterial surfaces. The amount of serum Vn and Fn which adsorbed onto tissue culture grade polystyrene (TCP) from different serum concentrations over the range of 0.1-30% (v/v) were determined and compared to attachment of cells of the BHK-21 and HT1080 fibroblast lines. There was no simple correlation between the amount of Fn or the amount of Vn adsorbed and cell attachment and spreading. The requirement for Fn or Vn for attachment and spreading of BHK-21 or HT1080 cells onto modified polystyrene (either TCP or to Primaria) during the first 90 min of cell culture was directly tested by selective removal of Fn or Vn from the serum prior to addition to the culture medium. Attachment and spreading of BHK-21 or HT1080 cells onto TCP or Primaria surfaces were reduced in a concentration-dependent manner when the cells were seeded in medium containing 2% (v/v) or higher concentrations of Vn-depleted serum. BHK-21 cells or HT1080 cells seeded in medium containing Fn-depleted serum (which contained Vn) attached and spread onto TCP or Primaria. Both BHK-21 cells and HT1080 cells failed to attach to TCP or Primaria when seeded in medium containing serum depleted of both Vn and Fn. The requirement for serum Vn or Fn for fibroblast attachment to TCP was also tested using cells of a human dermal fibroblast strain. The attachment of the dermal fibroblasts to TCP during the first 90 min of culture was not decreased by depletion of Vn from the 15% (v/v) serum, but there was a reduction in the proportion of the attached cells which had spread. Selective depletion of serum Fn did not have any effect on either cell attachment or spreading. Our results show that for fibroblast cells, particularly with cell lines such as BHK-21 or HT1080 but also with cell strains, the first binding of cells onto tissue culture polystyrene when plated in medium containing serum is a result of adsorption onto the surface of serum Vn. The adsorption of serum Vn onto the surface overcomes the effect of serum components which tend to decrease cell attachment. 相似文献
45.
46.
Glucose turnover values in the dog obtained with various species of labeled glucose. 总被引:8,自引:0,他引:8
N Altszuler A Barkai C Bjerknes B Gottlieb R Steele 《The American journal of physiology》1975,229(6):1662-1667
Recent studies proposed that [2T]glucose is preferable to [14C]-glucose as a tracer for the measurement of glucose turnover. However, higher values for glucose turnover were obtained using [2T]glucose than with [14C]glucose. The present study explores the merit of another species of tritiated glucose, [3T]glucose. Utilizing isotope-dilution principles, comparison is made of glucose turnover values determined by use of [2T]glucose, [3T]glucose, and [6-14C]glucose. Glucose turnover using [2T]glucose was 1.51 +/- 0.07 times greater than that using [6-14C]glucose, after correction for recycling of 14C. However, glucose turnover values obtained with [3T]glucose were similar to those obtained with [6-14C]glucose. There were no temporal or quantitative differences in appearance of tritium (T) in plasma water after injection of [2T]- and [3T]glucose. A methylprednisolone regimen in the normal dog increased glucose turnover as determined by all three tracers, but the increase observed using [2T]glusoce was significantly greater than that using that two other tracers. Thiement for [6-14C]glucose for measurement of glucose turnover in the dog. 相似文献
47.
The effect of lysozyme on the complement-dependent bactericidal action of different antibody classes. 下载免费PDF全文
Preparations of rabbit, dog and sheep IgA, IgA and IgM were examined for their antibacterial effects using a complement-dependent bactericidal assay. IgM and IgG were effecient bactericidal antibodies in the presence of complement; IgA, however, contained negligible activity. Except for sheep IgG no enhancement of bactericidal activity was observed in the presence of added lysozyme. 相似文献
48.
Previous work has established that CD24 is a costimulatory molecule for T-cell clonal expansion. Studies using CD24 -/- mice demonstrated that CD24 plays a critical role in the CD28-independent immune response against virus and soluble antigens. The role of CD24 on dendritic cells (DCs) has not been reported. Here, we compare the CD24(+/+) and CD24(-/-) DCs in the induction of initial clonal expansion and elicitation of memory CD4(+) T cells in vivo. Our results demonstrate that the CD24 expressed on DCs is essential neither for the induction of initial T-cell clonal expansion nor for elicitation of memory activity of primed T cells in vivo. 相似文献
49.
Muriel D. Ross 《Developmental dynamics》1974,139(4):449-481
Histochemical, x-ray analytical and scanning and transmission electron microscopical procedures have been utilized to determine the chemical nature, physical appearance and attachments of the tectorial membrane in normal rats and to correlate these results with biochemical data on protein-carbohydrate complexes. Additionally, pertinent histochemical and ultrastructural findings in chemically sympathectomized rats are considered. The results indicate that the tectorial membrane is a viscous, complex, colloid of glycoprotein(s) possessing some oriented molecules and an ionic composition different from either endolymph or perilymph. It is attached to the reticular laminar surface of the organ of Corti and to the tips of the outer hair cells; it is attached to and enclose the hairs of the inner hair cells. A fluid compartment may exist within the limbs of the “W” formed by the hairs on each outer hair cell surface. Present biochemical concepts of viscous glycoproteins suggest that they are polyelectrolytes interacting physically to form complex networks. They possess characteristics making them important in fluid and ion transport. Furthermore, the macromolecular configuration assumed by such polyelectrolytes is unstable and subject to change from stress or shifts in pH or ions. Thus, the attachments of the tectorial membrane to the hair cells may play an important role in the transduction process at the molecular level. 相似文献
50.