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111.
PURPOSE: To assess potential new prognostic factors and to validate the AIDS Clinical Trials Group (ACTG) for AIDS-related Kaposi's sarcoma (AIDS-KS) staging system in the highly active antiretroviral therapy (HAART) era. PATIENTS AND METHODS: We collected epidemiologic, clinical, staging, and survival data from 211 patients with AIDS-KS enrolled in two prospective Italian human immunodeficiency virus (HIV) cohort studies. We included in the analysis all patients with the diagnosis of KS made from January 1996, the time at which HAART became available in Italy. RESULTS: In the univariate analysis, survival was not influenced by sex, age, level of HIV viremia at KS diagnosis, HAART at KS diagnosis (HAART-na?ve v HAART-experienced), or type of HAART combination. Regarding ACTG classification, the 3-year survival rate was 85% for T0 patients and 69% for T1 patients (P =.007), 83% for S0 patients and 63% for S1 patients (P =.003), and 83% for I0 patients and 71% for I1 patients (P =.06). In the multivariate analysis, only the combination of poor tumor stage (T1) and poor systemic disease (S1) risk identified patients with unfavorable prognosis. The 3-year survival rate of patients with T1S1 was 53%, which was significantly lower compared with the 3-year survival rates of patients with T0S0, T1S0, and T0S1, which were 88%, 80%, and 81%, respectively (P =.0001). CONCLUSION: In the era of HAART, a refinement of the original ACTG staging system is needed. CD4 level does not seem to provide prognostic information. Two different risk categories are identified: a good risk (T0S0, T1S0, T0S1) and a poor risk (T1S1).  相似文献   
112.
PURPOSE: Malignant peripheral nerve sheath tumor (MPNST) can arise sporadically or in association with neurofibromatosis type 1. Deletions at the 9p21 locus have been reported in these tumors. To additionally characterize the status of this chromosomal region, in this study we performed a comprehensive, mostly PCR-based molecular analysis of the three tumor suppressor genes p15(INK4b), p14(ARF) and p16(INK4a) located at the 9p21 locus in 26 cryopreserved MPNSTs. EXPERIMENTAL DESIGN: Fourteen neurofibromatosis type 1-related and 12 sporadic cases were investigated for homozygous deletion coupled with fluorescent in situ hybridization, promoter methylation, and mutational analysis, as well as m-RNA expression. RESULTS: The results showed that an inactivation of one or more genes occurred in 77% of MPNSTs and was mainly achieved through homozygous deletion (46%), which, in turn, encompassed all of the three tandemly linked genes in 83% of the deleted cases. Promoter methylation was at a less extent involved in gene silencing (18%), and no mutations were found. Loss of function at DNA level strongly correlated with loss of mRNA expression accounting for 80% of the cases. Because of the close relationship between p14(ARF) and TP53 and between p15(INK4b)/p16(INK4a) and Rb, these results support a model of a coinactivation of TP53 and Rb pathways in 75% of MPNSTs, with functional consequences on cell growth control and apoptosis. CONCLUSIONS: The inactivation of the 9p21 locus is a frequent and peculiar hallmark of MPNST genetic profile leading also to an impaired apoptosis that could be taken into account in treatment planning of these tumors.  相似文献   
113.
PURPOSE: Imatinib (Glivec) is a potent inhibitor of bcr/abl, an oncogenic fusion protein that causes chronic myelogenous leukemia (CML). alpha1 acid glycoprotein (AGP) binds to imatinib with high affinity and inhibits imatinib activity in vitro and in vivo in an animal model. A pharmacokinetics analysis of imatinib was undertaken in CML patients. EXPERIMENTAL DESIGN: Imatinib plasma concentrations were measured in 19 CML patients treated with imatinib (400 or 600 mg/day). Five patients received a concomitant short-term course of clindamycin (CLI). RESULTS: A positive correlation between AGP and imatinib plasma levels was observed. CLI administration decreased imatinib plasma concentrations, evaluated as area under the curve (AUC) and peak concentrations (C(max)). The effects of a bolus of CLI was studied in three patients on imatinib 23 h after the last imatinib dose. Within 5-10 min in three of three cases, CLI caused a decrease in imatinib plasma concentrations of 2.6-, 2.7-, and 4.7-fold, respectively. In vitro experiments using fresh blasts from CML patients showed that AGP, at concentrations observed in the patients, decreased imatinib intracellular concentrations up to 10 times and blocked imatinib activity. The incubation with CLI restored imatinib intracellular concentrations and biological activity. CONCLUSION: AGP exerts significant effects of the pharmacokinetics, plasma concentrations, and intracellular distribution of imatinib in CML patients; these data indicate that plasma imatinib levels represent unreliable indicators of the cellular concentrations of this molecule.  相似文献   
114.
Purpose: To evaluate whether or not an intermediate dose of preoperative external radiation therapy intensified by systemic chemotherapy could improve the tumor response, sphincter preservation, and tumor control.

Methods and Materials: Between March 1990 and December 1995, 83 consecutive patients with resectable extraperitoneal adenocarcinoma of the rectum were treated with preoperative chemoradiation: bolus i.v. mitomycin C (MMC), 10 mg/m2, Day 1 plus 24-h continuous infusion i.v. 5-fluorouracil (5FU) 1000 mg/m2, Days 1–4, and concurrent external beam radiotherapy (37.8 Gy). All but 2 patients had T3 disease. Surgery was performed 4–6 weeks after the end of chemoradiation.

Results: Total Grade 3–4 acute toxicity during chemoradiation was observed in 11 (13%) patients: hematological Grade 3 toxicity was recorded in 8 (10%) patients, and Grade 4 toxicity was recorded in 2 (2%) patients. Grade 3 diarrhea was seen in 2 (2%) patients. No patient had major skin or urological acute toxicity. Two patients had no surgery: 1 died before surgery from septic complications after Grade 4 hematological toxicity; 1 refused surgery and is still alive after 6 years. There was no postoperative mortality and the overall perioperative morbidity rate was 25%. The analysis of tumor response involved 81 patients. Overall, 9% [7] of 81 patients had a complete pathologic response. Comparing the stage at the diagnostic workup with the pathologic stage, tumor downstaging was observed in 46 (57%) patients. We had 7 (9%) pT0, 5 (6%) pT1, 33 (41%) pT2, and 36 (44%) pT3. Nodal status downstaging was detected in 46 patients (57%). No evidence of nodal involvement was observed in 59 patients (73%). The incidence of tumor response was affected significantly by the number of quarters of rectal circumference involved (p = 0.03) and, marginally, by the length of the tumor (p = 0.09). The distance between the lower pole of the tumor and the anorectal ring had no influence. Of the patients, 63 (78%) had a sphincter-saving surgical procedure. In 12 (44%) of 27 patients candidate for an APR, the sphincter was preserved, as it was in 19 (95%) of 20 probable candidates. Lengthening of the distance between the anorectal ring and the lower pole of the tumor > 20 mm was observed in 21 patients (26%). Of 63 patients, 4 (6%) had moderate soilage after the sphincter-saving procedure.

Conclusion: Preoperative combined modality therapy seems to afford some potential advantages in nonrandomized trials: patients are able to tolerate higher chemotherapy doses and they experience a lower acute toxicity. Tumor downstaging and resectability rates are high; sphincter preservation is feasible. Larger T3 tumors remained less influenced by this treatment; thus, taking into account the low toxicity rate recorded, a more aggressive schedule should be applied in these resectable tumors.  相似文献   

115.
OBJECTIVE: Retrospective study and review of the complications other than those related to the facial nerve and hearing, encountered in acoustic neuroma surgery. Also, an evaluation of hospital stay and its relation with various factors. STUDY DESIGN: Retrospective case review. SETTING: Tertiary neurotologic and skull base referral center. PATIENTS: A series of 707 patients who underwent surgical removal of acoustic neuroma from April 1987 to December 2001. INTERVENTIONS: The surgical approaches used were the enlarged translabyrinthine approach, the enlarged middle fossa approach, and the retrosigmoid approach. In a small number of cases, the operations were performed through other approaches. MAIN OUTCOME MEASURES: The duration of hospital stay and appearance of complications in the perioperative period along with their management. Results related to the facial nerve and hearing were not considered in this study. RESULTS: The most frequent complication was abdominal subcutaneous hematoma (site of fat harvest), which occurred in 23 patients (3.2%). Cerebrospinal fluid leak was present in 20 patients (2.8%), 15 of whom needed revision surgery. Other complications included VIth cranial nerve dysfunction in 12 cases (1.68%), subdural hematoma in 3 cases (0.4%), cerebellopontine angle hematoma in 4 cases (0.6%), cerebellar edema in 2 cases (0.28%), brainstem hematoma in 1 case (0.14%), transitory aphasia in 1 case (0.14%), and lower cranial nerve dysfunction in 1 case (0.14%). Mortality occurred in only one case (0.14%). Medical complications seldom occurred. The postoperative hospital stay ranged from 2 to 36 days, with an average of 6.4 days. The overall hospital stay diminished over time from 10.2 days in 1987 to 1990, to 4.9 days in 2001. There was a significant relation between hospital stay and tumor size, approach used, and presence/absence of complications. CONCLUSIONS: Perioperative complications in acoustic neuroma surgery do exist, but this study demonstrated how low the incidence is. The authors believe that the low percentage of complications is mainly attributable to the majority of operations being carried out in specialized clinics, where they are considered routine operations. They believe that following individualized approaches, depending on tumor size and on the preoperative function of the cranial nerves, is the proper way to reach a significant reduction in complications while maintaining a high percentage of total tumor removal. The results of this study, considered as a basis of comparison with other studies, will certainly be useful in preoperative patient counseling.  相似文献   
116.
PURPOSE: A drug utilization trial was performed to investigate acute versus short-term effects after switching or adding bimatoprost in open-angle glaucoma patients over a 3- month observation period. METHODS: One (1) eye was randomly chosen from 47 glaucomatous patients (abnormal visual field and/or abnormal optic nerve and intraocular pressure (IOP) above 21 mmHg without treatment). Only patients who did not reach the target IOP with their ongoing treatment were recruited in this study. IOP was measured at baseline, after 1 hour, and 2 hours from the first instillation and after 1 week, 1, and 3 months of treatment. RESULTS: The IOP before bimatoprost administration was 20.16+/-3.6 mmHg (mean+/-standard deviation). There was no statistically significant decrease of IOP after 1 hour (mean IOP, 19.96+/-4.25 mmHg) and after 2 hours (mean IOP, 17.73+/-3.24 mmHg). Statistically significant (p<0.001) decreases after 1 week (mean IOP, 16.48+/-2.9 mmHg), after 1 month (mean IOP, 16.48+/-2.9 mmHg) and after 3 months (mean IOP, 16.15+/-2.7 mmHg) were found. CONCLUSION: The results suggested that bimatroprost had a significant acute effect on IOP in monotherapy, while no significant effect was found when the therapy was switched or added. The effect for primary open-angle glaucoma was very evident. There was no specific side effect attributable to combining bimatoprost with any of the treatments in use.  相似文献   
117.
男、女用避孕套临床可接受性的比较   总被引:4,自引:0,他引:4  
目的:比较男、女用避孕套的临床可接受性。方法:以40名健康育龄期妇女自愿者为研究对象,采用交叉设计,每人使用男女用避孕套各5个,每使用完一种后填写评价性调查表;使用完两种后,填写总结性调查表,对两种避孕套进行比较。结果:在避孕套的取出/取下、性生活中阴茎的插入、以及性生活中是否感觉不舒服(疼痛、烧灼感)等方面,对两种避孕套的评价基本相同。男用避孕套的主要优点是易学、易用,而女用避孕套可使性生活更有兴趣和感到更安全。总的说来,女性对使用两种避孕套的态度没有明显差异,而男性则比较喜欢使用男用避孕套。结论:通过适当的推广和改进,在我国会有一定比例的育龄妇女接受并使用女用避孕套。  相似文献   
118.
We report the case of a 30-year-old woman with cystic fibrosis (CF) chronically infected with Pseudomonas aeruginosa who delivered and breast-fed a healthy boy. While breast-feeding the woman had to undergo an i.v. antibiotic course with tobramycin, due to pulmonary exacerbation. Tobramycin was not detected in her milk and lactation could be continued. This is the first time that the presence of tobramycin in the milk of a CF woman during i.v. administration has been investigated.  相似文献   
119.
Few epidemiologic studies have investigated the potential relation between flavonoids and breast cancer risk. We have applied recently published data on the composition of foods and beverages in terms of six principal classes of flavonoids (i.e., flavanones, flavan-3-ols, flavonols, flavones, anthocyanidines, and isoflavones) on dietary information collected in a large-case control study of breast cancer conducted in Italy between 1991 and 1994. The study included 2,569 women with incident, histologically confirmed breast cancer, and 2,588 hospital controls. Odds ratios (OR) and 95% confidence intervals were estimated by multiple logistic regression models. After allowance for major confounding factors and energy intake, a reduced risk of breast cancer was found for increasing intake of flavones (OR, 0.81, for the highest versus the lowest quintile; P-trend, 0.02), and flavonols (OR, 0.80; P-trend, 0.06). No significant association was found for other flavonoids, including flavanones (OR, 0.95), flavan-3-ols (OR, 0.86), anthocyanidins (OR, 1.09), as well as for isoflavones (OR, 1.05). The findings of this large study of an inverse association between flavones and breast cancer risk confirm the results of a Greek study.  相似文献   
120.
Dietary folate and risk of prostate cancer in Italy.   总被引:2,自引:0,他引:2  
Folate status may affect cancer risk through its role in both methylation and nucleotide synthesis of DNA. A low dietary intake of folate has been linked to risk of several cancers, but epidemiologic studies with reference to prostate cancer are scanty. We therefore analyzed data from a case-control study of prostate cancer conducted between 1991 and 2002 in various areas of Italy. Cases were 1,294 patients with incident, histologically confirmed prostate cancer and controls were 1,451 patients admitted to the same network of hospitals of cases for acute, nonneoplastic conditions. All subjects were < 75 years old. Intake of folate and other nutrients was computed from a validated food frequency questionnaire. We adjusted for energy intake using the residual method, and calculated multivariate odds ratios (OR) and 95% confidence intervals (CI) using unconditional logistic regression. The OR of prostate cancer was 0.66 (95% CI, 0.51-0.85) for the highest versus the lowest quintile of folate intake. The relation between dietary folate and prostate cancer was consistent across strata of age, methionine, vitamin B6, and alcohol intake, and did not vary substantially according to Gleason score of prostate cancer. The combined OR for high-folate and low-alcohol intake versus low-folate and high-alcohol intake was 0.46 (95% CI, 0.29-0.75). Therefore, this study supports a favorable role of dietary folate on prostate cancer risk.  相似文献   
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