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21.
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U Pastorino  M Valente  V Bedini  A Pagnoni    G Ravasi 《Thorax》1982,37(9):680-683
The role of chronic cardiopulmonary disease as a risk factor for immediate and late mortality was evaluated retrospectively in a consecutive series of 116 patients who had had resections for stage Ia non-oat-cell lung cancers. The presence of chronic cardiopulmonary disease was diagnosed on the clinical history and preoperative assessment of lung and heart function by traditional means. Patients with chronic cardiopulmonary disease showed a lower five-year survival rate than controls--35% versus 53% (p less than 0.08). The difference increased and became significant if besides having cardiopulmonary disease the patient was over 60 years of age or had had a pneumonectomy--30% versus 52% (p less than 0.025). A higher operative mortality was the main reason for the lower observed survival. Nevertheless, survival of patients at risk exceeded 30% in each subgroup, being 33% for patients over 60 undergoing pneumonectomy. In our series the benefits of resection of lung cancer in patients with impaired cardiopulmonary function were greater than the risks of perioperative and later death even in the groups with a poorer prognosis.  相似文献   
23.
BACKGROUND: Patients receiving chemotherapy for lung cancer usually modify their lung function during treatment with increases in forced expiratory volume in 1 second (FEV(1)) and forced vital capacity (FVC) and decreases in lung diffusion for carbon monoxide (DLCO). This prospective study was designed to evaluate functional changes in forced expiratory volume in 1 second, forced vital capacity, and DLCO after three courses of induction chemotherapy with cisplatinum and gemcitabine in stage IIIa lung cancer patients and to assess their impact on respiratory complications after lung resection. METHODS: From March 1998 to January 2001, 30 consecutive patients with N2 nonsmall cell lung cancer had surgical resection after neoadjuvant treatment. Pre-chemotherapy and postchemotherapy results of standard respiratory function tests and DLCO were compared in patients with and without postoperative respiratory complications. RESULTS: All 30 patients completed the chemotherapy protocol without respiratory complications. Significant improvements (p < 0.05) were recorded after chemotherapy in transition dyspnea score, PaO(2) (mean value from 79.8 to 86.4 mm Hg), forced expiratory volume in 1 second % (from 78.1% to 87.5%) and forced vital capacity % (from 88.1% to 103.3%). Lung diffusion for carbon monoxide was significantly impaired after chemotherapy (from 74.1% to 65.7%; p = 0.0006), as well as DLCO adjusted for alveolar volume (from 92.8% to 77.4%; p < 0.0001). One patient died after surgery and 4 patients (13.3%) experienced postoperative respiratory complications. Compared with patients without complications, these 4 patients had higher mean increase in FEV(1) after chemotherapy (+26.8% vs + 6.7%; p = 0.025), but greater mean decrease in DLCO/Va (-27.8% vs -13.6%; p = 0.03). Impact of change in DLCO on postoperative respiratory complications was not confirmed by multiple logistic regression analysis (p = 0.16). CONCLUSIONS: In lung cancer patients, forced expiratory volume in 1 second and forced vital capacity assessed after neoadjuvant chemotherapy are not reliable indicators of the likelihood of respiratory complications after surgery. The risk of respiratory complication may be directly linked to loss of DLCO/Va. Lung diffusion for carbon monoxide assessed after neoadjuvant chemotherapy is probably the most sensitive risk indicator of respiratory complications after surgery. We recommend that DLCO studies be performed before and after chemotherapy in lung cancer patients undergoing induction therapy.  相似文献   
24.
OBJECTIVES: To address the potential role of the endothelial lectin-like oxidized low-density lipoprotein receptor-1 (LOX-1) in the thrombotic system, in this study we first examined whether platelet interaction with LOX-1 generated reactive oxygen species (ROS) and superoxide (O2.-) and then investigated the relationship between the intracellular production of O2.- and the availability of nitric oxide (NO). BACKGROUND: Oxidative inactivation of NO is regarded as an important cause of its decreased biologic activity which may favor platelet-dependent arterial thrombosis. METHODS: Bovine aortic endothelial cells (BAECs) and Chinese hamster ovary-K1 cells stably expressing bovine LOX-1 (BLOX-1-CHO) were incubated at different times with human platelets. The ROS, O2.-, and NO were measured in cells by flow cytometry. RESULTS: The incubation of BAECs and BLOX-1-CHO cells with human platelets induced a sharp and dose-dependent increase in intracellular concentration of ROS and O2.- (p from <0.01 to <0.001). The increase in intracellular concentration of O2.- was followed by a dose-dependent reduction in basal and bradykinin-induced intracellular NO concentration (p from <0.01 to <0.001). The increase in O2.- and the reduction of NO were inhibited by the presence of vitamin C and anti-LOX-1 monoclonal antibody (p < 0.001). CONCLUSIONS: The results of this study show that one of the pathophysiologic consequences of platelet binding to LOX-1 may be the inactivation of NO through an increased cellular production of O2.-.  相似文献   
25.
Hexokinase II is often highly expressed in poorly differentiated and rapidly growing tumors that exhibit a high rate of aerobic glycolysis. Hexokinase II binds to the mitochondrial membrane through its interaction with the outer membrane voltage-dependent anion channel (VDAC), preferentially at contact sites between the outer and inner mitochondrial membrane. This location is thought to be important for the integration of glycolysis with mitochondrial energy metabolism. VDAC is a critical component of the mitochondrial phase of apoptosis and its interaction with Bcl-2 family proteins controls the rate of release of mitochondrial intermembrane space proteins that activate the execution phase of apoptosis. The proteins involved in the contact sites also constitute the mitochondrial permeability transition, one of the mechanisms by which mitochondrial protein release can be mediated. Hexokinase II binding to VDAC suppresses the release of intermembrane space proteins and inhibits apoptosis, thereby contributing to the survival advantage of tumor cells. This interaction places hexokinase II in a position to integrate glycolytic metabolism of the tumor cell with the control of apoptosis at the mitochondrial level. Mitochondrial binding of hexokinase II may constitute an attractive target for therapeutic intervention to suppress tumor growth.  相似文献   
26.
BACKGROUND: Although a growing body of literature regarding polyoma BK virus (BKV) infection and associated interstitial nephritis in kidney-allograft recipients is becoming available, the impact of BKV infection in the pediatric population has not been fully evaluated. METHODS: In a retrospective analysis, we performed polymerase chain reaction (PCR) assays for BKV DNA in serum and urine samples from 100 pediatric kidney-allograft recipients referred to our institution in the last 5 years. RESULTS: BKV viruria was observed in 26 of 100 patients, whereas BKV viremia was demonstrated in 5 patients. Serum creatinine was significantly higher in recipients with positive BK viremia compared with BKV DNA-negative patients (mean 2.66 vs. 1.14 mg/100 mL). Renal biopsy performed in 3 of 5 patients showed graft damage consistent with interstitial nephropathy. In the univariate analysis, negative antibody status of the recipient and the presence of mycophenolate mofetil in baseline immunosuppression were the two factors predictive of active BKV infection. CONCLUSIONS: Our study shows that BKV-associated nephropathy is a relevant complication in the pediatric kidney transplantation setting also. Identification of patients at risk of developing virus-associated nephropathy, through prospective quantification of viral load, could improve clinical outcome by allowing the use of timely preemptive therapy guided by BKV DNA levels.  相似文献   
27.
Neuroblastoma (NB) is the most common extracranial solid tumor of childhood. In advanced disease stages, prognosis is poor and treatments have limited efficacy, thus novel strategies are warranted. The synthetic retinoid fenretinide (HPR) induces apoptosis in NB and melanoma cell lines. We reported an in vitro potentiation of HPR effects on melanoma cells when the drug is incorporated into GD2-targeted immunoliposomes (anti-GD2-SIL-HPR). Here, we investigated the antitumor activity of anti-GD2-SIL-HPR against NB cells, both in vitro and in vivo. Anti-GD2-immunoliposomes (anti-GD2-SIL) showed specific, competitive binding to, and uptake by, various NB cell lines. Moreover, anti-GD2-SIL-HPR presented increased selectivity and efficacy in inhibiting NB cell proliferation through the induction of apoptosis, compared to free drug and SL-HPR. In an in vivo NB metastatic model, we demonstrated that anti-GD2-SIL-HPR completely inhibited the development of macroscopic and microscopic metastases in comparison to controls. However, similar, but significantly less potent antitumor effect was observed also in mice treated with anti-GD2 immunoliposomes without HPR (anti-GD2-SIL-blank) or anti-GD2 mAb alone (P=0.0297 and P=0.0294, respectively, vs. anti-GD2-SIL-HPR). Moreover, our results clearly demonstrated that, although anti-GD2 mAb had a strong antitumor effect in this in vivo NB model, 100% curability was obtained only following treatment with anti-GD2-SIL-HPR (P<0.0001). Anti-GD2 liposomal HPR should receive clinical evaluation as adjuvant therapy of neuroblastoma.  相似文献   
28.
The poor selective toxicity of chemotherapeutic anticancer drugs leads to dose-limiting side effects that compromise clinical outcome. Solid tumors recruit new blood vessels to support tumor growth, and unique epitopes expressed on tumor endothelial cells can function as targets for the anti-angiogenic therapy of cancer. An NGR peptide that targets aminopeptidase N, a marker of angiogenic endothelial cells, was coupled to the surface of liposomal doxorubicin (NGR-SL[DXR]) and was used to treat orthotopic neuroblastoma (NB) xenografts in SCID mice. Pharmacokinetic studies indicated that liposomes coupled to NGR peptide had long-circulating profiles in blood. Their uptake into NB tumor was time dependent, being at least 10 times higher than that of nontargeted liposomes (SL[DXR]) after 24 h, with DXR spreading outside the blood vessels and into the tumors. No uptake was observed into tumors of mice treated with the mismatched peptide ARA-targeted SL[DXR]. Tumor-specific DXR uptake was completely blocked when mice were coinjected with a 50-fold molar excess of the soluble NGR peptide. Adrenal tumor-bearing mice treated with 2 mg/kg/week/x3 of NGR-SL[DXR] partly outlived the control mice (P < 0.001), whereas doses > 3 mg/kg/week/x3 were toxic. Histopathological analysis of cryosections taken from treated mice revealed pronounced destruction of the tumor vasculature with a marked decreased in vessel density. Double staining of tumors with terminal deoxynucleotidyl transferase-mediated nick end labeling and antifactor VIII antibody or antihuman NB demonstrated endothelial cell apoptosis in the vasculature, as well as increased tumor cell apoptosis. Moreover, mice injected with 3 mg/kg/week/x3 of NGR-SL[DXR] displayed rapid tumor regression, as well as inhibition of metastases growth (P = 0.0002). One day after the third treatment, four of six mice showed no evidence of tumors, and the two others showed a >80% reduction in tumor mass and a >90% suppression of blood vessel density (P < 0.01). In contrast, mice treated with ARA-SL[DXR] formed large well-vascularized tumors. Finally, a metronomic administration of NGR-SL[DXR] (1 mg/kg/every other 2 days x 9) induced complete tumor eradication in all animals (P < 0.0001). Our strategy markedly enhanced the therapeutic index of DXR and enabled metronomic administration of therapeutic doses. A dual mechanism of action is proposed: indirect tumor cell kill via the destruction of tumor endothelium by NGR-targeted liposomes and direct tumor cell kill via localization of liposomal DXR to the tumor interstitial space. This combined strategy has the potential to overcome some major limitations of conventional chemotherapy.  相似文献   
29.
This paper addresses the quantitative investigation of the contribution of spontaneous (SOAE) to click-evoked (TEOAE) otoacoustic emissions in newborns. The hypothesis was that a weighted linear combination of the spontaneous peaks is strongly similar to the corresponding click-evoked emissions. After identification of the main spontaneous peaks for each subject, a best fit procedure was applied to find the amplitude and phase of each spontaneous tone in the weighted summation. The comparison of the weighted signal (SpTEOAE) with the actual click-evoked response (TEOAE) from the same subject was performed, obtaining correlation coefficient higher than 50% in more than 100 ears over 132.  相似文献   
30.
Surgical resection offers the best chance for cure for early stage non-small-cell lung cancer (NSCLC, stage I, II, IIIA), but the 5-year survival rates are only moderate, with systemic relapse being the major cause of death. Pre-operative (neo-adjuvant) chemotherapy has shown promise in small trials restricted to stage IIIA patients. We believe similar trials are now appropriate in all stages of operable lung cancer. A feasibility study was performed in 22 patients with early stage (IB, II, IIIA) resectable NSCLC; randomized to either three cycles of chemotherapy [mitomycin-C 8 mg m(-2), vinblastine 6 mg m(-2) and cisplatin 50 mg m(-2) (MVP)] followed by surgery (n = 11), or to surgery alone. Of 40 eligible patients, 22 agreed to participate (feasibility 55%) and all complied with the full treatment schedule. All symptomatic patients achieved either complete (50%) or partial (50%) relief of tumour-related symptoms with pre-operative chemotherapy. Fifty-five per cent achieved objective tumour response, and a further 27% minor tumour shrinkage; none had progressive disease. Partial pathological response was seen in 50%. No severe (WHO grade III-IV) toxicities occurred. No significant deterioration in quality of life was detected during chemotherapy. Pre-operative MVP chemotherapy is feasible in early stage NSCLC, and this study has now been initiated as a UK-wide Medical Research Council phase III trial.  相似文献   
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