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71.

Background

PTX is one of the most widely used drug in oncology due to its high efficacy against solid tumors and several hematological cancers. PTX is administered in a formulation containing 1:1 Cremophor® EL (polyethoxylated castor oil) and ethanol, often responsible for toxic effects. Its encapsulation in colloidal delivery systems would gain an improved targeting to cancer cells, reducing the dose and frequency of administration.

Methods

In this paper PTX was loaded in PLGA NS. The activity of PTX-NS was assessed in vitro against thyroid, breast and bladder cancer cell lines in cultures. Cell growth was evaluated by MTS assay, intracellular NS uptake was performed using coumarin-6 labelled NS and the amount of intracellular PTX was measured by HPLC.

Results

NS loaded with 3% PTX (w/w) had a mean size < 250 nm and a polydispersity index of 0.4 after freeze-drying with 0.5% HP-Cyd as cryoprotector. PTX encapsulation efficiency was 30% and NS showed a prolonged drug release in vitro. An increase of the cytotoxic effect of PTX-NS was observed with respect to free PTX in all cell lines tested.

Conclusion

These findings suggest that the greater biological effect of PTX-NS could be due to higher uptake of the drug inside the cells as shown by intracellular NS uptake and cell accumulation studies.
  相似文献   
72.
BACKGROUND: In routine practice, the distinction between isolated tumor cells (ITC) and micrometastases (MIC) in patients with breast cancer is sometimes difficult to discern. The authors assessed differences in classifying patients according to the American Joint Commission on Cancer (AJCC) and the International Union Against Cancer (UICC) definitions and method of sizing. METHODS: We assessed the characteristics of metastatic deposits in only 1 involved lymph node in 337 patients with operable breast cancer (median follow-up, 15.3 years). When sizing multiple clusters, either the diameter of the area with close clusters (Method 1) or the size of the largest cluster (Method 2) was taken into account. Patients were classified and their survival was assessed according to the 2 sizing methods and the criteria used for definitions (size in AJCC; size and topography in UICC). RESULTS: With the AJCC definitions, 32 patients would be differently classified according to the method of sizing. With the UICC definitions, some patients with parenchymal ITC would be classified as pN1mi, 38 by Method 1 and 53 by Method 2. Some pathologists would classify the 66 patients who had isolated capsular vascular invasion as pN0. Classification was uncertain in 136 (40%) to 151 (45 %) patients. Survival was not significantly different between pN0(i+) and pN1(mi) patients. CONCLUSIONS: The distinction between ITC and MIC was often difficult and without any prognostic significance. Precise guidelines are more useful for staging than for therapy. Thus, complete axillary dissection is usually performed in pN0(i+) and pN1(mi) patients, whereas chemotherapy is not indicated or debatable when MIC is the only 1 pejorative criterion.  相似文献   
73.
Food sharing is vital for a large number of species, either solitary or social, and is of particular importance within highly integrated societies, such as in colonial organisms and in social insects. Nevertheless, the mechanisms that govern the distribution of food inside a complex organizational system remain unknown.  相似文献   
74.
The authors performed laser vaporization in 240/250 cases for viral pathology of the lower genital tract, obtaining recovery at the first treatment in 232/240 cases and at the second in 238/248 cases.  相似文献   
75.
Combination intraventricular chemotherapy for meningeal neoplasia   总被引:3,自引:0,他引:3  
Twenty two patients with meningeal neoplasia were treated with biweekly combination intraventricular chemotherapy using methotrexate, cytosine arabinoside, and thiotepa. Patients with the following malignancies were included: breast cancer, ten patients; lung cancer, seven; non-Hodgkin's lymphoma, two; malignant melanoma, one; transitional cell carcinoma of the bladder, one; and malignant glioma, one. Eight of 22 patients (36%) had a Karnofsky performance status of less than 50%. Eleven of 22 patients received radiotherapy to symptomatic areas, and seven received systemic chemotherapy in addition to combination intraventricular therapy. Patients were evaluated for both toxicity and response to therapy. Myelosuppression was the major toxic condition and occurred in 17 of 22 patients (77%). Ten patients (45%) had a nadir WBC count of less than 1000/microL or a platelet count of less than 25,000/microL. No patient achieved a complete response (CR), although nine patients (41%) had partial responses (PRs) lasting 4 to 24 + weeks. Median survival for the entire group was 10 weeks (range, 6 to 24+ weeks). In this small group of patients, simultaneous triple-drug intraventricular chemotherapy caused unacceptable myelosuppression without increasing the response rate, response duration, or survival when compared with single-agent methotrexate and radiotherapy.  相似文献   
76.
77.
During the last century, obesity has become a global epidemic. The effect of obesity on renal transplantation may occur in perioperative complications and impairment of organ function. Obese patients have metabolic derangements that can be exacerbated after transplantation and obesity directly impacts most transplantation outcomes. These recipients are more likely to develop adverse graft events, such as delayed graft function and early graft loss. Furthermore, obesity is synergic to some immunosuppressive agents in triggering diabetes and hypertension. As behavioral weight loss programs show disappointing results in these patients, bariatric surgery has been considered as a means to achieve rapid and long-term weight loss.Up-to-date literature shows laparoscopic bariatric surgery is feasible and safe in transplantation candidates and increases the rate of transplantation eligibility in obese patients with end-stage organ disease. There is no evidence that restrictive procedures modify the absorption of immunosuppressive medications. From 2013 to 2016 we performed six bariatric procedures (sleeve gastrectomy) on obese patients with renal transplantation; mean preoperative body mass index (BMI) was 39.8 kg/m2. No postoperative complication was observed and no change in the immunosuppressive medications regimen was needed. Mean observed estimated weight loss was 27.6%, 44.1%, 74.2%, and 75.9% at 1, 3, 6, and 12 months follow-up, respectively. Our recommendation is to consider patients with BMI >30 kg/m2 as temporarily ineligible for transplantation and as candidates to bariatric surgery if BMI >35 kg/m2. We consider laparoscopic sleeve gastrectomy as a feasible, first-choice procedure in this specific population.  相似文献   
78.
79.
ObjectiveAbout 15% of colorectal adenocarcinomas have a deficient DNA mismatch repair phenotype. The frequency of deficient DNA mismatch repair tumours increases with age due to the hypermethylation of hMLH1 promoter. The study aimed to determine the prognostic value of deficient DNA mismatch repair phenotype in elderly patients.DesignMismatch repair phenotype was retrospectively determined by molecular analysis in consecutive resected colorectal adenocarcinoma specimens from patients over 75 years of age from 4 Oncology centres.Results231 patients (median age: 81, range: 75–100) were enrolled from 2005 to 2008. Mean prevalence of deficient DNA mismatch repair phenotype was 22.5%, and 36% for patients over 85 years. Deficient DNA mismatch repair status was significantly associated with older age, female sex, proximal colon primary and high grade tumour. For stage II tumours no deficient DNA mismatch repair tumours had a recurrence at end of follow-up compared to 17% for tumours with proficient phenotype. The proficient phenotype status was significantly associated with worse age-adjusted overall survival [HR 2.60; 95% CI 1.05–6.44; p = 0.039]. For stage III tumours a trend for less recurrence was observed for deficient DNA mismatch repair phenotype (16%) compared to proficient phenotype (36%).Conclusiondeficient DNA mismatch repair phenotype is a prognostic factor in stage II colorectal tumour in elderly patients. Our results suggest that mismatch repair phenotype should be taken in consideration for adjuvant chemotherapy decision in elderly patients.  相似文献   
80.
Neurological Sciences - Telephone-based cognitive screening (TBCS) is crucial to telehealth care of neurological patients, prevention campaigns, and epidemiological studies on cognitive impairment....  相似文献   
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