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91.
PURPOSE: Up-regulation of both inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) enzymes has been reported in colorectal cancer. We aimed at evaluating the possible interaction between the nitric oxide and COX-2 pathways, and its effect on promoting tumor angiogenesis. EXPERIMENTAL DESIGN: Expression of iNOS, COX-2, vascular endothelial growth factor (VEGF), and CD31 was analyzed in tumor samples and corresponding normal mucosa obtained from 46 surgical specimens. We also evaluated iNOS activity, prostaglandin E(2) (PGE(2)), cyclic GMP and cyclic AMP production in the same specimens. Nitrite/nitrate levels, and PGE(2) and VEGF production were assessed in HCT116 and HT29 colon cancer cell lines after induction and selective inhibition of the two enzyme pathways. RESULTS: A significant correlation was found between iNOS and COX-2 immunohistochemical expression. PGE(2) production significantly correlated with iNOS activity and cGMP levels. A significant correlation was also found among PGE(2) production, microvessel density, and VEGF expression. Coinduction of both iNOS and COX-2 activities occurred after lipopolysaccharide (LPS) and epidermal growth factor (EGF) treatment in HCT116 and HT29 cells. Inhibition of iNOS by 1400W significantly reduced both LPS- and EGF-induced PGE(2) production. Treatment with LPS, EGF, and arachidonic acid significantly increased VEGF production in the iNOS-negative/COX-2-positive HT29 cells. This effect was completely reversed by treatment with the selective COX-2 inhibitor celecoxib. CONCLUSIONS: Our data showed a prominent role of nitric oxide in stimulating COX-2 activity in colorectal cancer. This interaction is likely to produce a cooperative effect in promoting angiogenesis through PGE(2)-mediated increase in VEGF production.  相似文献   
92.
PURPOSE: Gemcitabine is an inhibitor of ribonucleotide reductase (RR) and DNA synthesis and is an effective agent in the treatment of pancreas cancer. The present study investigates whether the multitargeted antifolate pemetrexed would be synergistic with gemcitabine against MIA PaCa-2, PANC-1, and Capan-1 pancreatic cancer cell lines. EXPERIMENTAL DESIGN: Cells were treated with gemcitabine and pemetrexed, and the type of drug interaction was assessed using the combination index. Cytotoxicity of gemcitabine was examined with inhibitors of (a) deoxycytidine kinase (dCK), which activates gemcitabine by phosphorylation, and (b) 5'-nucleotidase (drug dephosphorylation) and cytidine deaminase (drug deamination), the main inactivating enzymes. The effects of gemcitabine and pemetrexed on cell cycle were analyzed by flow cytometry, and apoptosis was examined by fluorescence microscopy. Finally, quantitative, real-time PCR was used to study the pharmacogenetics of the drug combination. RESULTS: Synergistic cytotoxicity and enhancement of apoptosis was demonstrated, mostly with the sequence pemetrexed-->gemcitabine. Pemetrexed increased cells in S phase, the most sensitive to gemcitabine, and a positive correlation was found between the expression ratio of dCK:RR and gemcitabine sensitivity. Indeed, pemetrexed significantly enhanced dCK gene expression (+227.9, +86.0, and +135.5% in MIA PaCa-2, PANC-1, and Capan-1 cells, respectively), and the crucial role of this enzyme was confirmed by impairment of gemcitabine cytotoxicity after dCK saturation with 2'-deoxycytidine. CONCLUSIONS: These data demonstrate that the gemcitabine and pemetrexed combination displays schedule-dependent synergistic cytotoxic activity, favorably modulates cell cycle, induces apoptosis, and enhances dCK expression in pancreatic cancer cells.  相似文献   
93.
PURPOSE: Bone metastases are associated with severe and sometimes intractable pain, compromising patient quality of life (QOL). This open-label pilot study investigated the effects of short-term intensive treatment with intravenous (i.v.) ibandronate on opioid-resistant bone pain in patients with skeletal metastases. PATIENTS AND METHODS: Eighteen patients with advanced tumors and metastatic bone disease received nonstandard treatment with 4 mg of ibandronate administered i.v. (2-hour infusion) for 4 consecutive days (16-mg total dose). Baseline opioid analgesic use was equivalent to 400 mg/d of morphine. Patients were assessed for 6 weeks or until death. Changes from baseline were determined for bone pain, opioid consumption, patient functioning, QOL, performance status, and biochemical markers of calcium metabolism and bone turnover. Renal function was assessed by serum urea and creatinine measurement. RESULTS: Short-term, intensive ibandronate treatment significantly reduced bone pain scores within 7 days (P <.001). Pain reductions were sustained over the study period. Ibandronate significantly improved QOL, patient functioning, and performance status (P <.05). Mean values of the urinary cross-links pyridinoline and deoxypyridinoline tended to increase after day 21, returning close to baseline values by day 42. There was no correlation between the change in crosslinks values and the change in pain scores after ibandronate treatment. Ibandronate was well tolerated, with no evidence of renal toxicity. CONCLUSION: Nonstandard, intensive treatment with i.v. ibandronate seems to have a marked analgesic effect in patients with opioid-resistant bone pain from metastatic bone disease. Further investigation is warranted.  相似文献   
94.
The aim of this paper was to establish if duplex ultrasound parameters obtained for assessment of the patency of cavernosal arteries in the penile flaccid state can give sufficient clinical information without the use of intracavernosal injection of vasodilatory drugs. We assessed mean cavernosal peak systolic velocity (PSV) in the penile flaccid state (basal PSV), and after PGE1 injection (dynamic PSV) in 339 unselected patients with erectile dysfunction. In 55 of these patients the waveform acceleration in the flaccid state was also assessed. The results of the study can be summarized as follows: (1) a significant relationship was found between basal and dynamic PSV in the 339 patients (r=0.477; p < 0.0001); (2) a basal PSV >12.5 cm/sec was predictive of a dynamic PSV >/=30 cm/sec in 129/139 (92.8%) of the patients, whereas in patients with a basal PSV or <30 cm/sec could be found; and (3) an acceleration >1 m/sec2 in the flaccid state was coupled to a dynamic PSV >30 cm/sec in 43/46 (93.5%) of the patients independent of the basal PSV. In conclusion, these results suggest that the combined duplex ultrasound assessment of PSV and waveform acceleration in the penile flaccid state can predict arterial dynamic inflow in the majority (51/55; 92.7%) of patients with erectile dysfunction, with less time and expense and less discomfort for the patient.  相似文献   
95.
Uteroglobin and transglutaminase modulate human sperm functions   总被引:3,自引:0,他引:3  
During the process of capacitation, spermatozoa undergo significant changes in membrane composition, including removal of decapacitating factors (DFs), which are present in seminal plasma, that lead to increased sensitivity to physiological stimuli of the acrosome reaction. In the present study we investigated the presence, localization, and effects on human spermatozoa of 2 proteins of seminal plasma origin, uteroglobin (UG) and transglutaminase (TG). These 2 proteins interact with one another because TG promotes covalent links of UG to sperm surface proteins. We found that UG is localized around the entire surface of ejaculated human sperm, whereas TG is predominantly localized in the neck. FACScan analysis confirmed the surface localization of both antigens and demonstrated that swim-up selection of spermatozoa was associated with a significant reduction in the contents of the 2 substances when compared with unselected samples. Western blot analysis of UG in total sperm lysates confirmed the lower content of the protein in swim-up-selected sperm. Swim-up-selected sperm were characterized by their ability to undergo a spontaneous, time-dependent increase of capacitation-characteristic chlortetracycline pattern of fluorescence and increase in responsiveness to progesterone. Such changes were not observed in unselected sperm. Exogenous addition of TG, together with recombinant rabbit UG, prevented the spontaneous increase in responsiveness to progesterone (acrosome reaction and intracellular calcium) at 24 hours in swim-up-selected sperm, suggesting the occurrence of a capacitation-inhibiting activity of the 2 substances. In addition, we found that endogenous UG and TG contents, as determined by FACScan analysis, were negatively correlated (P < .0001) with sperm motility and that exogenous addition of the 2 substances resulted in a substantial reduction of progressive motility (P < .01). Collectively, these data indicate that TG and UG represent 2 DFs, and contribute to understanding the biochemical mechanisms that characterize the process of capacitation.  相似文献   
96.
OBJECTIVES: To assess, in women participating in a breast cancer prevention trialon fenretinide (4-HPR), the relationship of drug and retinol levels with the risk of second breast malignancy, taking into account age and menopausal status. METHODS: In a multicenter prevention trial, women with early breast cancer were randomly assigned to receive no treatment or 200 mg of 4-HPR/day for 5 years. Blood was collected at baseline and on a yearly basis during intervention from women recruited at the Istituto Tumori (Milan, Italy; 818 and 756 in the 4-HPR and control arm, respectively, who accounted for 53% of the participants in the trial). The plasma concentrations of 4-HPR, its main metabolite N-(4-methoxyphenyl) retinamide, and retinol were assayed by high-performance liquid chromatography. Three age ranges (or=56 years), menopausal status at baseline, and disease outcome at a median follow-up of 97 months were taken into account in the analysis. RESULTS: Baseline retinol levels were significantly lower (P or=46 years versus or= 0.71; P 相似文献   
97.
Capacitive heating is widely used in hyperthermic treatment of human malignancies. However, the pain on the body surface or thermoesthesia in the subcutaneous fatty layer may prevent an elevation of temperature in the tumors. Impedance matching is improved by a subtrap method entailing the application of two copper plates (10×850×0.06 mm) as a subtrap circuit to each of two capacitive electrodes. In a clinical trial the Tmax, Tave, Tmin for the subtrap method were all higher in comparison with those for the conventional technique (42.5±0.7°C, 41.9±1.0°C, 41.3±1.1°C vs. 41.1±1.5°C, 40.6±1.3°C, 40.0±1.3°C). Although the maximal radiofrequency (RF) power applied to patients was higher with the subtrap method (875±189 W vs. 763±200 W), the incidence of surface pain was reduced dramatically. It is concluded that the subtrap method substantially improves the RF capacitive heating of deep-seated tumors.  相似文献   
98.
Hibernomas are rare soft tissue tumors of brown fat differentiation. A case of a large axillary hibernoma, along with a review of its pathology, is presented. This tumor matches the largest hibernoma in the literature and is the largest in an axillary site.  相似文献   
99.
The authors report the results obtained in 16 patients affected with displaced fracture of the acetabulum treated surgically and mobilized passively immediately after surgery by means of a continuous passive mobilization apparatus for the hip. The age of the patients at the time of trauma ranged from 21 to 54 years. The posterior wall was involved in 12 cases, while the anterior column was also involved in 4. Excellent or good reduction of the fracture was obtained in all of the cases. Immediately after surgery, a continuous passive motion apparatus for the hip was applied to be used for approximately 3 weeks. At final follow-up, which was obtained after a mean time of 5 years, all of the patients except 2 had obtained good results. Moderate joint deficit was present in 1 case, while sciatic nerve palsy that had already been observed prior to surgery persisted in another. Evident radiographic signs of coxarthrosis were not present in any of the cases. Based on the opinion of Salter et al. (1980), who in an experimental study had observed better healing of the cartilaginous lesions in the joints submitted to movement, immediately after surgery we applied a continuous passive motion apparatus for the hip in a group of patients affected with fracture of the acetabulum. As none of the patient followed-up by us presented evident signs of hip arthrosis, the authors hypothesize that continuous passive movement, immediately carried out after osteosynthesis, plays a significant role in preventing post-traumatic arthrosis of the hip. In truth, small irregularities of the acetabular cavity, possibly present after an apparently anatomical reduction, could be minimized by the plasmating effect of the head of the femur in movement.  相似文献   
100.
BACKGROUND: Long-term left ventricular assist devices (LVAD) have been used both as a bridge to heart transplantation and to recovery of native myocardial function. Despite much evidence for reversal of some of the structural and functional changes present in the failing heart during LVAD support, clinical evidence for sustained myocardial recovery is scant. We describe 2 patients in whom myocardial recovery during LVAD support led to device explanation only to have heart failure recur. This necessitated a second LVAD implantation, a process that we have termed recurrent remodeling. METHODS: The medical records of 2 patients with cardiomyopathy supported with HeartMate LVADs (Thermo Cardiosystems, Inc, Woburn, MA) were retrospectively reviewed. RESULTS: One patient was supported with an LVAD for 2 months, at which time the LVAD was explanted. Progressive deterioration of cardiac function followed, requiring a second LVAD 19 months after LVAD explanation. After 2 months of further LVAD support, a second episode of apparent myocardial recovery was observed during a period of device malfunction. The other patient was supported with an LVAD for 12 months, at which time the LVAD was explanted. The patient experienced progressive hemodynamic deterioration and required a second LVAD 6 months after LVAD explantation. Heart transplantations of both patients were successful. CONCLUSIONS: Our understanding of myocardial recovery in the setting of hemodynamic unloading with LVAD support has not yet progressed to the point where we are able to accurately predict successful long-term LVAD explantation. The evolution of reliable predictors of sustainable myocardial recovery will help to avoid further cases of recurrent remodeling requiring repeat LVAD implantation.  相似文献   
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