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91.
Barbareschi M Roldo C Zamboni G Capelli P Cavazza A Macri E Cangi MG Chilosi M Doglioni C 《The American journal of surgical pathology》2004,28(9):1169-1176
CDX-2 is a homeobox gene product essential for intestinal development and differentiation. It can be used as a specific marker of colorectal adenocarcinomas and other tumors with intestinal differentiation, but little is known about its expression in endocrine and neuroendocrine (NE) cells and NE primary and metastatic tumors. Using the Cdx-2-88 monoclonal antibody, we evaluated CDX-2 expression in routine samples of 20 normal endocrine/NE tissues and of 299 samples of well-differentiated NE tumors (WDNET) and high-grade NE carcinomas (NEC) from different sites. For 17 cases, we examined primary and corresponding metastatic lesions. We also examined 8 cytologic samples of liver metastases derived from 4 ileal WDNETs, 1 lung WDNET, and 3 pancreatic endocrine tumors. CDX-2 mRNA expression with RT-PCR technique on frozen material was evaluated in 5 WDNETs. CDX-2 was expressed in normal NE cells of the intestine and gastric fundus. High CDX-2 expression was seen in all ileal and appendiceal WDNET, while low levels were seen in WDNETs from stomach, duodenum, and rectum; no reactivity was seen in other WDNETs. Low levels of CDX-2 expression were seen in one third of nonfunctioning pancreatic WDNET where it was more frequently observed in cases with metastatic disease (P = 0.002). CDX-2 was identified in all cytologic specimens of metastatic ileal WDNETs. CDX-2 mRNA analysis confirmed immunohistochemical results. CDX-2 was expressed at high levels in 81% of intestinal NEC. Unexpectedly, variable levels of expression of CDX-2 were seen also in 39% of NEC of other sites, without any relation with the site of origin. This reactivity frequently overlapped TTF-1 expression, suggesting deregulated expression of homeobox genes in NEC. The restricted pattern of CDX-2 expression may have diagnostic value in the identification of the primary site of a metastatic WDNET. Conversely, a limited diagnostic role is suggested for CDX-2 in NEC because of its frequent expression in nongastrointestinal tumors. 相似文献
92.
Tartagni M Cicinelli E Schonauer MM Causio F Petruzzelli F Loverro G 《Journal of andrology》2004,25(5):781-783
This study was designed to evaluate the effectiveness and clinical usefulness of the hypo-osmotic swelling (HOS) test in predicting successful conception in couples in which men with mild male-factor infertility criteria were undergoing a timed vaginal inter-course protocol. One hundred couples, in which mild male infertility was the only abnormality, were included in the study. Semen was analyzed according to standard World Health Organization (WHO) criteria and subjected to the HOS test. Patients were divided into 2 groups: group 1 (n=39) with normal HOS test and group 2 (n=61) with abnormal HOS test. All women underwent three consecutive cycles of follicular growth ultrasound monitoring and timed intercourse. Ten couples were exclude from the study. Ten clinical pregnancies were achieved in group 1 with a pregnancy rate per patient and per cycle of 28.5% and 9.5%, respectively. In group 2, 6 pregnancies were achieved, with a pregnancy rate per patient and per cycle of 10.9% and 3.6%, respectively. Both pregnancy rates per patients and per cycle was significantly higher (P <.05) in group 1 than in group 2. The HOS test may be considered an easy and reliable test in identifying among subfertile men those who have a greater possibility of causing pregnancy. 相似文献
93.
Experimental posterolateral spinal fusion with porous ceramics and mesenchymal stem cells 总被引:3,自引:0,他引:3
Cinotti G Patti AM Vulcano A Della Rocca C Polveroni G Giannicola G Postacchini F 《The Journal of bone and joint surgery. British volume》2004,86(1):135-142
Alternatives to autogenous bone graft for spinal fusion have been investigated for many years. It has been shown that osteoconductive materials alone do not give a rate of fusion which is comparable to that of autogenous bone graft. We analysed the effectiveness of porous ceramic loaded with cultured mesenchymal stem cells as a new graft material for spinal fusion in an animal model. Posterolateral fusion was carried out at the L4/L5 level in 40 White New Zealand rabbits using one of the following graft materials: porous ceramic granules plus cultured mesenchymal stem cells (group I); ceramic granules plus fresh autogenous bone marrow (group II); ceramic granules alone (group II); and autogenous bone graft (group IV). The animals were killed eight weeks after surgery and the spines were evaluated radiographically, by a manual palpation test and by histological analysis. The rate of fusion was significantly higher in group I compared with group III and higher, but not significantly, in group I compared with groups II and IV. In group I histological analysis showed newly formed bone in contact with the implanted granules and highly cellular bone marrow between the newly formed trabecular bone. In group II, thin trabeculae of newly formed bone were present in the peripheral portion of the fusion mass. In group III, there was a reduced amount of newly formed bone and abundant fibrous tissue. In group IV, there were thin trabeculae of newly formed bone close to the decorticated transverse processes and dead trabecular bone in the central portion of the fusion mass. In vitro cultured mesenchymal stem cells may be loaded into porous ceramic to make a graft material for spinal fusion which appears to be more effective than porous ceramic alone. Further studies are needed to investigate the medium- to long-term results of this procedure, its feasibility in the clinical setting and the most appropriate carrier for mesenchymal stem cells. 相似文献
94.
Pelosi E Pellerito R Clerico P Migliaretti G Rosso U Bisi G 《Nuclear medicine communications》2004,25(6):603-608
OBJECTIVES: (1). To identify the main parameters that positively influence the outcome of knee radiosynoviorthesis (RSO) in patients with rheumatoid arthritis (RA) and (2). to determine the ideal candidate for this procedure. METHODS: We considered 80 knees (in 57 patients) that had undergone follow-up for at least 5 years and/or prosthesis implantation after RSO treatment. The parameters evaluated included age, gender, oligo-articular or polyarticular involvement, disease progression, radiological joint damage (Larsen scale), instability and/or axial deviation, body mass index (BMI), and psychological motivation for prosthesis implantation. RESULTS: Knee Larsen stage IV, presence of instability-axial deviation, disease progression, psychological motivation to the surgical replacement and BMI higher than the 85th percentile were associated with a negative outcome for RSO (prosthesis implantation). CONCLUSIONS: The ideal candidate for the RSO treatment is a patient with a low Larsen stage, no instability and/or axial deviation and a BMI below the 85th percentile. A patient's psychological motivation for the treatment should be evaluated before the RSO procedure. 相似文献
95.
Barbagli G Palminteri E Balò S Vallasciani S Mearini E Costantini E Constantini E Mearini L Zucchi A Vivacqua C Porena M 《Urologia internationalis》2004,73(1):1-5
INTRODUCTION: The true incidence of urethral involvement in patients with genital lichen sclerosus (LS) is unknown. We review the epidemiology and discuss the pathogenesis of LS and urethral stricture diseases. MATERIALS AND METHODS: During the period 1991-2002, of 925 patients who underwent urethroplasty for anterior urethral stricture, 130 patients (14%) received the diagnosis of LS. In all patients with LS the histology was re-examined to confirm the clinical diagnosis. Retrograde and voiding urethrography was used to establish urethral involvement in the disease. RESULTS: In 106 patients (82%) the histology provided the classical features of LS, and 24 patients (18%) showed some histological variations. In 49 patients (37%) the LS involved the pendolous urethra (meatus-navicularis-penile), and in 53 cases (41%) a panurethral stricture was evident. CONCLUSIONS: LS urethral involvement appears to be a much more common and extensive disease than previously reported, and requires particular care in its early diagnosis. 相似文献
96.
The efficacy and tolerability of the combination of valsartan and hydrochlorothi-azide (HCTZ) were compared with that of amlodipine
in reducing ambulatory blood pressure and plasma norepinephrine levels in patients with mild to moderate hypertension and
at least 1 cardiovascular risk factor. At the end of a 2-week washout period, 92 outpatients with a sitting diastolic blood
pressure ≥95 and <110 mm Hg, associated with at least 1 additional risk factor, were randomly assigned to receive either valsartan
160 mg and HCTZ 12.5 mg once daily (n=46) or amlodipine 10 mg alone once daily (n=46) for 12 weeks, according to a prospective,
randomized, open-label, blinded end point, parallel-group design. At the end of the washout period and after 6 and 12 weeks
of active treatment, 24-hour ambulatory blood pressure monitoring was performed, and clinical blood pressure and heart rate
and plasma norepinephrine levels were assessed (by high-performance liquid chromatography). Both the valsartan/HCTZ combination
and amlodipine had a demonstrable antihypertensive effect, but the combination showed an antihypertensive effect significantly
greater than that of amlodipine, as demonstrated by the 24-hour (P < .001), daytime (P < .001), and nighttime ambulatory blood pressure values (P < .01) and by the clinical blood pressure values at trough, which were all significantly lower. Although the trough-to-peak
ratios were similar in both groups, the smoothness indexes pertaining to both systolic and diastolic pressures were significantly
higher (P < .05 andP < .001, respectively) in patients receiving valsartan/HCTZ, suggesting the combination produces a more homogeneous antihypertensive
effect. A significant increase in plasma norepinephrine levels was associated with amlodipine (+9% at 6 weeks, +15% at 12
weeks) but not with the valsartan/HCTZ combination. The valsartan/HCTZ combination was better tolerated than amlodipine, which
was associated with a higher frequency of ankle edema. These results indicate that the combination of valsartan 160 mg and
HCTZ 12.5 mg provides more sustained and homogeneous control of blood pressure than does amlodipine 10 mg in high-risk hypertensive
patients, without producing reflex sympathetic activation. 相似文献
97.
Acute respiratory distress syndrome (ARDS) is a clinical syndrome of non-cardiogenic pulmonary oedema associated with bilateral pulmonary infiltrates, stiff lungs and refractory hypoxaemia. ARDS is characterized by an explosive acute inflammatory response in the lung parenchyma, leading to alveolar oedema, decreased lung compliance and, ultimately, hypoxaemia. Although our understanding of the causes and pathophysiology of ARDS has increased, the mortality rate remains in the range of 30-50%. No major advances in pharmacological therapy have been achieved. Mechanical ventilation is the main therapeutic intervention in the management of ARDS. The only approach that has been shown to reduce the inflammatory response and mortality is the use of lung-protective ventilatory strategy with a low tidal volume and high positive-end expiratory pressure. This chapter will review the current state of the literature on the pathogenesis of ARDS and ventilatory and pharmacotherapy approaches to its management. 相似文献
98.
Bolognese A Correale G Manfra M Lavecchia A Mazzoni O Novellino E La Colla P Sanna G Loddo R 《Journal of medicinal chemistry》2004,47(4):849-858
New antiproliferative compounds, the 1-aryl-3-ethoxycarbonyl-pyrido[2,3-g]isoquinolin-5,10-diones (PIQDs, 1-7), were designed on the basis of a molecular model obtained by aligning the common quinolinquinone substructure of 5H-pyrido[3,2-a]phenoxazin-5-one (PPH) and some known anticancer agents. A Diels-Alder reaction between quinolin-5,8-dione (QD) and a 2-azadiene, formed by demolition of 2-aryl-1,3-thiazolidine ethyl esters (T compounds), was used to produce 1-7 and the isomeric 1-aryl-3-ethoxycarbonylpyrido[3,2-g]isoquinolin-5,10-diones (8-14). Two other compounds, the 3-amino-3-ethoxycarbonyldihydrothieno[2,3-g]quinolin-4,9-dione (15) and the 3-amino-3-ethoxycarbonyldihydrothieno[3,2-g]quinolin-4,9-dione (16), arising from a 1,4 Michael reaction of QD with a thiolate species formed by opening of T compounds, were recovered from the reaction mixture. The antiproliferative activity of 1-16 was evaluated against representative human liquid and solid neoplastic cell lines. The IC(50) of these compounds had median values in the range 2.00-0.01 microM, with 2-4 and 15 exhibiting significantly higher in vitro cytotoxic activity. Compound 2, also evaluated against KB subclones (KB(MDR), KB(7D), and KB(V20C)), was shown to be scarcely subject to the MDR1/P-glycoprotein drug efflux pump responsible for drug resistance. The noncovalent DNA-binding properties of PIQDs were examined using UV-vis and (1)H NMR spectroscopy experiments. Accordingly, these compounds were confirmed to have an ability to intercalate into double-stranded DNA by topoisomerase I superhelix unwinding assay. Interesting structure-activity relationships were found. Three important features seem to contribute to the cytotoxic activity of these anticancer ligands: (i) the DNA intercalating capability of the three-cyclic quinonic system, typical of this class of compounds, (ii) the position of the pendant phenyl ring that, according to the superimposition model, must occupy the same area of the corresponding benzo-fused ring A of PPH, and (iii) the effect of electron-withdrawing substituents on the phenyl ring, which can contribute improving the pi-pi stacking interactions between ligand and DNA base pairs. Besides, a mechanism of action suspected to involve topoisomerases could be hypothesized to interpret the antiproliferative activity of the thienoquinolindione 15, which can be regarded as a cyclic cysteine derivative. 相似文献
99.
Bosetti C Talamini R Montella M Negri E Conti E Franceschi S La Vecchia C 《International journal of cancer. Journal international du cancer》2004,112(4):689-692
Several studies have evaluated the possible association between intakes of retinoids and carotenoids and the risk of prostate cancer, but the evidence is still inconsistent. Further, only a few studies have investigated the role of specific carotenoids other than beta-carotene. We have thus considered the association between retinol and various carotenoids using data from a multicentric case-control study conducted in Italy between 1991 and 2002. This included 1,294 incident, histologically confirmed prostate cancer cases below age 75 years admitted to major teaching and general hospitals in the areas under study, and 1,451 controls below age 75 years selected among patients admitted to the same hospitals as cases for a wide spectrum of acute nonneoplastic conditions not related to long-term modifications of diet. Subjects' usual diet was investigated by means of a validated food-frequency questionnaire. Multivariate odds ratios and the corresponding 95% confidence intervals were estimated using unconditional logistic regression models. The risk of prostate cancer tended to decrease with increasing intake of retinol (OR=0.79 for the highest versus the lowest quintile of intake), carotene (OR=0.70), alpha-carotene (OR=0.85) and beta-carotene (OR=0.72), although the estimates were significant for carotene and beta-carotene only. No meaningful associations emerged for nonprovitamin A carotenoids, such as lycopene (OR=0.94) and lutein/zeaxanthin (OR=0.91). No systematic heterogeneity was observed across strata of age, education and body mass index. Thus, our study supports the hypothesis of a weak protective effect of carotene, particularly beta-carotene, on the risk of prostate cancer, while it indicates that other carotenoids, including lycopene, and retinol are not appreciably related to the risk of this neoplasm. 相似文献
100.