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981.
PURPOSE: To evaluate the usefulness of the high-resolution computed tomography (HRCT) visual score in idiopathic pulmonary fibrosis (IPF) and its correlation with respiratory function tests. MATERIAL AND METHODS: We studied the pulmonary function tests and HRCT scans of 42 IPF patients, at presentation (T0) and follow-up (T1: mean 13.7 months post-diagnosis). Of the 42 patients, 21 had been treated with steroid and immunosuppresion therapy. The pulmonary function tests considered were vital capacity (VC), diffusion lung capacity for carbon monoxide (D(L)CO) and arterial blood oxygen partial pressure (PaO(2)). The main HRCT parameters were type of lesion, and site and extent, the latter calculated by means of the visual score. RESULTS: Between T0 and T1, both mean HRCT score (from 43.57% to 50.64%) and lung function tests worsened (VC from 68.43% to 64.18%; D(L)CO from 36.31% to 28.97%; PaO(2) from 76.31 to 68.89 mmHg), without considerable differences between treated and untreated patients. At presentation (T0), the HRCT visual score had a significant correlation with lung function tests and these correlated with one another. Similar correlations were found at T1, but not for HRCT score and D(L)CO. In the interval between T0 and T1 the variations correlated significantly with each other, with two exceptions: HRCT score and D(L)CO, and D(L)CO and PaO(2). DISCUSSION AND CONCLUSIONS: IPF exhibited a progressive deterioration both in HRCT extent of disease and lung function impairment. There is a significant correlation between HRCT visual score and lung function tests both at diagnosis and at follow-up. The HRCT study is able to identify and quantify anatomic IPF and also to evaluate the progression of the disease. In clinical practice, the HRCT visual score of disease extent can be used in association with function tests to monitor IPF evolution, and to evaluate prognosis and therapy. In the future, helical CT with 3D model construction will provide a more precise IPF quantification with automatic score. 相似文献
982.
Nonlethal conditioning for the induction of allogeneic chimerism and tolerance to islet allografts 总被引:6,自引:0,他引:6
BACKGROUND: We reported that tolerance to skin grafts can be achieved by chimerism induction by way of nonlethal conditioning. In the present study, we evaluated the outcome of islet allografts implanted either simultaneously or after donor bone marrow cell (BMC) infusion when nonlethal conditioning was used. METHODS AND RESULTS: B10 (H-2b) mice were conditioned with antilymphocyte serum (ALS), 100 cGy total body irradiation (TBI), and given 30 x 10(6) allogeneic (B10.BR, H-2k) BMC on day 0. On day 2, cyclophosphamide was given intraperitoneally (IP), followed by a second BMC infusion on day 3. After chimeras were typed for allogeneic BMC engraftment on day 28, animals were rendered diabetic chemically and transplanted under the kidney capsule with islet allografts genetically matched or disparate to the BM. Donor-specific islet grafts were accepted (median survival time [MST] > 180 days, n=6), whereas all major histocompatibility complex (MHC)-disparate third-party BALB/c (H-2d) islet grafts were rejected (MST=13.8 days, n=4). When B10.BR BMC and islets were given simultaneously, graft acceptance (MST >140 days, n=4) was observed. Surprisingly, when MHC-disparate third-party islets (BALB/c) were given together with B10.BR BMC, long-term survival was also observed (MST >100 days, n=3). These findings suggested that conditioning alone at the time of islet implant might induce long-term engraftment without further treatment. However, only chimeric animals accepted a second-set donor-specific graft, whereas all other groups rejected it. CONCLUSION: Our data indicates that stable allogeneic chimerism and islet indefinite survival can be achieved by the use of a nonmyeloablative protocol. The results of the conditioning-only experiments are consistent with the possibility of graft accommodation. 相似文献
983.
Fenjves ES Ochoa MS Cabrera O Mendez AJ Kenyon NS Inverardi L Ricordi C 《Transplantation》2003,75(8):1356-1360
984.
Frega A Cenci M Stentella P Cipriano L De Ioris A Alderisio M Vecchione A 《Cancer letters》2003,194(1):21-24
Human papillomavirus (HPV) infection is one of the most common sexual transmitted diseases (STDs). We compared two groups of virgins with genital HPV lesions to evaluate the behaviour at risk in the transmission of HPV infection. Partners were also examined. HPV lesions were detected in 88 virgins, who have never had sexual intercourse. This can be due to vertical transmission, fomities and skin-to-skin contact. Many other hypothesis can be proposed to explain HPV genital infection, however, further studies are required. 相似文献
985.
Cozzarini C Fiorino C Ceresoli GL Cattaneo GM Bolognesi A Calandrino R Villa E 《International journal of radiation oncology, biology, physics》2003,55(3):688-694
PURPOSE: Investigating the correlation between dosimetric/clinical parameters and late rectal bleeding in patients treated with adjuvant or salvage radiotherapy after radical prostatectomy. METHODS AND MATERIALS: Data of 154 consecutive patients, including three-dimensional treatment planning and dose-volume histograms (DVHs) of the rectum (including filling), were retrospectively analyzed. Twenty-six of 154 patients presenting a (full) rectal volume >100 cc were excluded from the analysis. All patients considered for the analysis (n = 128) were treated at a nominal dose equal to 66.6-70.2 Gy (ICRU dose 68-72.5 Gy; median 70 Gy) with conformal (n = 76) or conventional (n = 52) four-field technique (1.8 Gy/fr). Clinical parameters such as diabetes mellitus, acute rectal bleeding, hypertension, age, and hormonal therapy were considered. Late rectal bleeding was scored using a modified Radiation Therapy Oncology Group scale, and patients experiencing >or=Grade 2 were considered bleeders. Median follow-up was 36 months (range 12-72). Mean and median rectal dose were considered, together with rectal volume and the % fraction of rectum receiving more than 50, 55, 60, and 65 Gy (V50, V55, V60, V65, respectively). Median and quartile values of all parameters were taken as cutoff for statistical analysis. Univariate (log-rank) and multivariate (Cox hazard model) analyses were performed. RESULTS: Fourteen of 128 patients experienced >or=Grade 2 late bleeding (3-year actuarial incidence 10.5%). A significant correlation between a number of cutoff values and late rectal bleeding was found. In particular, a mean dose >or=54 Gy, V50 >or=63%, V55 >or=57%, and V60 >or=50% was highly predictive of late bleeding (p or=63% and those with V50 <63% (DVH grouping), data were fitted with a Cox regression hazard model using DVH grouping, rectal volume, and the main clinical parameters as independent variables. Results of the analysis showed that DVH grouping (relative risk 3.3; p = 0.04) and acute bleeding (relative risk 7.1; p = 0.001) are independently predictive of late bleeding. CONCLUSIONS: DVHs of the rectum are significantly correlated with late bleeding for patients irradiated at 66.6-70.2 Gy after radical prostatectomy. 相似文献
986.
Valentini V Piermattei A Morganti AG Gambacorta MA Azario L Macchia G Deodato F Cilla S Pepe D Grimaldi L Dinapoli N Cellini N 《Rays》2003,28(3):293-298
In the last two decades there was a radical change in radiotherapy setup. The growing availability of CT equipment and console for computer-aided treatment planning setup enabled the use of advanced technologies as conformal 3D radiation therapy in most centers. In particular in 1987 virtual simulation was proposed for setup. During its use a number of application modalities appeared. Virtual simulation in some centers is applied alone while in others it is associated with conventional simulation. However, from numerous reports published in last years it seems that virtual simulation significantly improves treatment quality independently of radical or palliative intent and of the size of treated volumes (high doses to small volumes or wide shaped fields). Some studies stressed that virtual simulation could significantly shorten treatment planning times with consequent cost reduction. The use of virtual simulation evidenced associated problems and in particular setup limitations due to the CT gantry size, the need to up-date the conventional modalities of setup verification according to the new technologies and more generally to up-date quality assurance procedures in an advanced technological setting. Finally there was the self-evident need of a better knowledge of the anatomy on axial sections, of tumor spread routes in particular. 相似文献
987.
De Luca A Mangiacasale R Severino A Malquori L Baldi A Palena A Mileo AM Lavia P Paggi MG 《Cancer research》2003,63(6):1430-1437
By means of the yeast two-hybrid system, we have discovered a novel physical interaction between the adenovirus E1A oncoprotein and Ran, a small GTPase which regulates nucleocytoplasmic transport, cell cycle progression, and mitotic spindle organization. Expression of E1A elicits induction of S phase and centrosome amplification in a variety of rodent cell lines. The induction of supernumerary centrosomes requires functional RCC1, the nucleotide exchange factor for Ran and, hence, a functional Ran network. The E1A portion responsible for the interaction with Ran is the extreme NH(2)-terminal region (amino acids 1-36), which is also required for the induction of centrosome amplification. In an in vitro assay with recombinant proteins, wild-type E1A interferes with nucleotide exchange on Ran, whereas an E1A mutant, deleted from the extreme NH(2)-terminal region, does not. In addition, we detected an in vitro interaction between Ran and HPV-16 E7 and SV40 large T antigen, two oncoproteins functionally related to E1A. These findings suggest a common pathway of these oncoproteins in eliciting virus-induced genomic instability. 相似文献
988.
Hyperthermia inhibits angiogenesis by a plasminogen activator inhibitor 1-dependent mechanism 总被引:14,自引:0,他引:14
Roca C Primo L Valdembri D Cividalli A Declerck P Carmeliet P Gabriele P Bussolino F 《Cancer research》2003,63(7):1500-1507
Hyperthermia (HT) associated with radiotherapy or chemotherapy is a promising method for cancer treatment, although the molecular mechanisms of this process are not well understood. HT exhibits various antitumor effects, including damage of tumor vasculature. Here, we investigate the effect of HT on in vitro and in vivo angiogenesis. We show that heat treatment of endothelial cells (ECs) affect their differentiation into capillary-like structures in two models of in vitro angiogenesis. Furthermore, the formation of new vessels promoted by angiogenic inducers in the chick embryo chorioallantoic membrane assay is impaired after heat treatment. These effects cannot be explained by direct cytotoxicity but are dependent on modulation of angiogenesis-involved genes. Gene expression profile of ECs subjected to heat shock demonstrates that plasminogen activator inhibitor 1 (PAI-1), a protein involved in the control of extracellular matrix degradation, is specifically up-regulated. The use of anti-PAI-1-neutralizing antibodies reverts the effect of HT on the in vitro EC morphogenesis and in vivo vessel formation. Moreover, microvessel outgrowth from PAI-1(-/-) aortic rings was not affected by HT compared with aortic rings from PAI-1(+/+) mice. Heat treatment of murine mammary adenocarcinomas results in inhibition of tumor growth, associated with a reduction of microvessel number and an increase of PAI-1 expression. These results indicate that heat-mediated PAI-1 induction is an important pathway by which HT exerts its antitumor activity and may represent a rationale for a combined cancer therapy based on HT associated with antiangiogenic molecules. 相似文献
989.
Microarray analysis and RNA silencing link fra-1 to cd44 and c-met expression in mesothelioma 总被引:5,自引:0,他引:5
Malignant mesothelioma is a cancer with poor prognosis associated with exposures to asbestos. The mechanisms of asbestos-induced mesotheliomas are unclear, and studies are required to find diagnostic tools and therapies to improve the survival rates of patients. After oligonucleotide microarray analysis (Affymetrix array) of normal rat pleural mesothelial (RPM) cells, RPM cells exposed to crocidolite asbestos, and rat mesotheliomas, subsets of genes that changed in expression were categorized, including the highly up-regulated, early response proto-oncogene, fra-1. Increases in fra-1 in both rat and human mesotheliomas and a subset of genes common to both asbestos-exposed RPM cells and mesotheliomas that mimicked fra-1 patterns of expression were subsequently confirmed using real-time quantitative PCR. Using RNA interference technology, fra-1 gene silenced RPM cells were assayed by real-time quantitative PCR for the expression of possible fra-1-regulated genes. Results reveal that induction of cd44 and c-met is causally linked to fra-1 expression, connecting fra-1 with genes governing cell motility and invasion in mesothelioma. These studies suggest that inhibition of fra-1 signaling pathways may be a strategy for therapy of malignant mesothelioma. 相似文献
990.
Godard S Getz G Delorenzi M Farmer P Kobayashi H Desbaillets I Nozaki M Diserens AC Hamou MF Dietrich PY Regli L Janzer RC Bucher P Stupp R de Tribolet N Domany E Hegi ME 《Cancer research》2003,63(20):6613-6625
The development of targeted treatment strategies adapted to individual patients requires identification of the different tumor classes according to their biology and prognosis. We focus here on the molecular aspects underlying these differences, in terms of sets of genes that control pathogenesis of the different subtypes of astrocytic glioma. By performing cDNA-array analysis of 53 patient biopsies, comprising low-grade astrocytoma, secondary glioblastoma (respective recurrent high-grade tumors), and newly diagnosed primary glioblastoma, we demonstrate that human gliomas can be differentiated according to their gene expression. We found that low-grade astrocytoma have the most specific and similar expression profiles, whereas primary glioblastoma exhibit much larger variation between tumors. Secondary glioblastoma display features of both other groups. We identified several sets of genes with relatively highly correlated expression within groups that: (a). can be associated with specific biological functions; and (b). effectively differentiate tumor class. One prominent gene cluster discriminating primary versus nonprimary glioblastoma comprises mostly genes involved in angiogenesis, including VEGF fms-related tyrosine kinase 1 but also IGFBP2, that has not yet been directly linked to angiogenesis. In situ hybridization demonstrating coexpression of IGFBP2 and VEGF in pseudopalisading cells surrounding tumor necrosis provided further evidence for a possible involvement of IGFBP2 in angiogenesis. The separating groups of genes were found by the unsupervised coupled two-way clustering method, and their classification power was validated by a supervised construction of a nearly perfect glioma classifier. 相似文献