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101.
Glioblastoma multiforme (GM) is the most common and most malignant astrocytoma in adults. After surgery, radiation therapy extends patient survival; however, in vivo response to radiation therapy is variable. The purpose of this investigation was to determine whether the cytogenetic abnormalities of GM differ according to patient response to radiation therapy. Radiation response was defined by either progression [radiation-resistant (RR)] or resolution [radiation-sensitive (RS)] of tumor at the first postradiation radiographic imaging evaluation. Twenty RR and 10 RS frozen tissue specimens were subjected to cytogenetic analysis by comparative genomic hybridization. RS and RR specimens had different cytogenetic aberrations that mapped predominantly to chromosomes 7, 9, 10, 13, and 19. Relative gain of 7 occurred in 70% of the RR and 30% of the RS cases and was the most significant difference involving a single change between the two groups (P = 0.06). RR and RS specimens also differed in their patterns of simultaneous cytogenetic aberrations. A simultaneous gain of chromosomes 7 and 19 was found in 30% of the RR cases but was absent in the RS group. Concurrent loss of 9p23-24 and 13q14 regions was absent in the RS cohort but occurred in 30% of the RR series. This latter cytogenetic pattern was also associated with older age. Amplifications were more common in the RR series, but the difference did not reach statistical significance. The data suggest that GM with different in vivo responses to radiation therapy also differ cytogenetically.  相似文献   
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103.
Pancreatic cancer (PC) continues to pose a major clinical challenge. There has been little improvement in patient survival over the past few decades, and it is projected to become the second leading cause of cancer mortality by 2030. The dismal 5-year survival rate of less than 10% after the diagnosis is attributable to the lack of early symptoms, the absence of specific biomarkers for an early diagnosis, and the inadequacy of available chemotherapies. Most patients are diagnosed when the disease has already metastasized and cannot be treated. Cancer interception is vital, actively intervening in the malignization process before the development of a full-blown advanced tumor. An early diagnosis of PC has a dramatic impact on the survival of patients, and improved techniques are urgently needed to detect and evaluate this disease at an early stage. It is difficult to obtain tissue biopsies from the pancreas due to its anatomical position; however, liquid biopsies are readily available and can provide useful information for the diagnosis, prognosis, stratification, and follow-up of patients with PC and for the design of individually tailored treatments. The aim of this review was to provide an update of the latest advances in knowledge on the application of carbohydrates, proteins, cell-free nucleic acids, circulating tumor cells, metabolome compounds, exosomes, and platelets in blood as potential biomarkers for PC, focusing on their clinical relevance and potential for improving patient outcomes.  相似文献   
104.
Free radicals are usually reactive species, characterized by the possession of one or more unpaired electrons. This molleculles are involved in the pathogenesis of various respiratory diseases. Free radicals have been evaluated in the bronchoalveolar lavage to understand the importance of its role in lung cancer, adult respiratory distress syndrome, interstitial pulmonary diseases, tobacco induced pulmonary damage, hyperoxia and drug-induced lung toxicity. There are evidences suggesting that these agents play an important role in lung injury. These findings could lead the development of new, and more effective, therapeutic agents in some respiratory diseases.  相似文献   
105.
This study was conducted to determine the maximum tolerated dose and dose-limiting toxicity of irinotecan (CPT-11) administered every 3 weeks to adults with progressive malignant glioma who were treated with enzyme inducing antiepileptic drug (EIAED) therapy, and to compare the pharmacokinetics with those in patients not on EIAED therapy treated at the recommended phase 2 dose for other cancers. The CPT-11 dose was 350 mg/m(2) i.v. every 3 weeks and remained fixed in patients not on EIAED therapy, but the dose was escalated by 50-mg/m(2) increments in patients on EIAED therapy. CPT-11 and its metabolites SN-38, SN-38 glucuronide (SN-38G), and APC (7-ethyl-10[4-N-(5 aminopentanoic acid)-1-piperidine]-carbonyloxycamptothecin) were characterized in both groups. Patients on EIAEDs received 350 to 800 mg/m(2) of CPT-11. Dose-limiting toxicity was due to grade 3 diarrhea despite maximal doses of loperamide. The systemic levels of CPT-11, APC, SN-38G, and SN-38 were all lower in the EIAED group. There was a moderate-to-fair relationship between CPT-11 dose and the area under the curve (AUC) for CPT-11 and APC over the 2, but no relationship dosage range of 350 to 800 mg/m between CPT-11 dose and the AUC for SN-38 or SN-38G. At the 750-mg/m(2) dose, the AUC for CPT-11 (21.6 microg x h/ml) matched the AUC (21.6 microg x h/ml) in the non-EIAED group treated with 350 mg/m(2) of CPT-11. We conclude that the recommended phase 2 dose of CPT-11 for patients on EIAEDs is 750 mg/m(2) when given every 3 weeks. A phase 2 study of patients with recurrent malignant glioma is ongoing to assess the efficacy of CPT-11 when the dose is stratified according to the use of EIAEDs.  相似文献   
106.
PURPOSE: Temozolomide (TMZ) and 13-cis-retinoic acid (cRA) have shown activity in prior single-agent trials of recurrent malignant gliomas (MG). This phase II trial evaluated efficacy and toxicity of combination temozolomide and cRA treatment in recurrent MG. PATIENTS AND METHODS: Adults with recurrent supratentorial MG for whom surgery, radiation, and/or chemotherapy failed were eligible. Treatment included oral TMZ 150 or 200 mg/m2/d, days 1 through 5, and cRA 100 mg/m2/d, days 1 to 21, every 28 days. Primary end point was progression-free survival at 6 months (PFS 6); secondary end points included response, survival, and PFS12. RESULTS: Eighty-eight eligible patients (glioblastoma multiforme [n = 40]; anaplastic gliomas [n = 48; astrocytoma, 28; oligodendroglioma, 14; mixed glioma, six]) received treatment. PFS 6 was 43% (95% confidence interval [CI], 33% to 54%) and PFS12 was 16% (95% CI, 10% to 26%). Median overall PFS was 19 weeks (95% CI, 16 to 27 weeks), and median overall survival (OS) was 47 weeks (95% CI, 36 to 58 weeks). OS was 46% (95% CI, 36% to 57%) at 52 weeks and 21% (95% CI, 13% to 31%) at 104 weeks. Of 84 assessable patients, there were two (3%) complete responses and eight (12%) partial responses (complete plus partial response, 15%). Among 499 treatment cycles, the most common grade 3/4 events included granulocytopenia (1.8%), thrombocytopenia (1.4%), and hypertriglyceridemia (1.2%). CONCLUSION: TMZ and cRA were active, exceeding our 20% thresholds for PFS 6 success, assuming 20% improvement over our previously reported database (glioblastoma multiforme: expected, 30%; observed, 32%; anaplastic glioma: expected, 40%; observed, 50%).  相似文献   
107.
In 2008, the Spanish Society of Pulmonology (SEPAR) published the first guidelines in the world on the diagnosis and treatment of bronchiectasis. Almost 10 years later, considerable scientific advances have been made in both the treatment and the evaluation and diagnosis of this disease, and the original guidelines have been updated to include the latest scientific knowledge on bronchiectasis. These new recommendations have been drafted following a strict methodological process designed to ensure the quality of content, and are linked to a large amount of online information that includes a wealth of references. These guidelines cover aspects ranging from a consensual definition of bronchiectasis to an evaluation of the natural course and prognosis of the disease. The topics of greatest interest and some new areas are addressed, including epidemiology and economic costs of bronchiectasis, pathophysiological aspects, the causes (placing particular emphasis on the relationship with other airway diseases such as chronic obstructive pulmonary disease and asthma), clinical and functional aspects, measurement of quality of life, radiological diagnosis and assessment, diagnostic algorithms, microbiological aspects (including the definition of key concepts, such as bacterial eradication or chronic bronchial infection), and the evaluation of severity and disease prognosis using recently published multidimensional tools.  相似文献   
108.
Lung mucormycosis is a rare fungal infection that has been described mainly in oncologic and diabetic patients. We here report the case of an endobronchial lesion caused by this fungus in an immunocompetent person. Prompt diagnosis, and therapy with Amphotericin B and surgery, permitted the complete resolution.  相似文献   
109.
110.
The clinical use of 5-fluorouracil, one of the drugs of choice in colon cancer therapy, is limited by a nonuniform oral absorption, a short plasma half-life, and by the development of drug resistances by malignant cells. We hypothesized that the formulation of biodegradable nanocarriers for the efficient delivery of this antitumor drug may improve its therapeutic effect against advanced or recurrent colon cancer. Hence, we have engineered two 5-fluorouracil-loaded nanoparticulate systems based on the biodegradable polymers poly(butylcyanoacrylate) and poly(ε-caprolactone). Drug incorporation to the nanosystems was accomplished by entrapment (encapsulation/dispersion) within the polymeric network during nanoparticle synthesis, i.e., by anionic polymerization of the monomer and interfacial polymer disposition, respectively. Main factors determining 5-fluorouracil incorporation within the polymeric nanomatrices were investigated. These nanocarriers were characterized by high drug entrapment efficiencies and sustained drug-release profiles. In vitro studies using human and murine colon cancer cell lines demonstrated that both types of nanocarriers significantly increased the antiproliferative effect of the encapsulated drug. In addition, both nanoformulations produced in vivo an intense tumor growth inhibition and increased the mice survival rate, being the greater tumor volume reduction obtained when using the poly(ε-caprolactone)-based formulation. These results suggest that these nanocarriers may improve the antitumor activity of 5-fluorouracil and could be used against advanced or recurrent colon cancer.KEY WORDS: 5-fluorouracil, colon cancer, poly(butylcyanoacrylate), poly(ε-caprolactone), polymeric nanoparticles  相似文献   
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