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991.
Purpose To evaluate the circadian effects on intraocular pressure (IOP) and ocular perfusion pressure (OPP) of 0.5% timolol or 0.005% latanoprost in Caucasian patients affected by normal-tension glaucoma (NTG). Patients and methods In this crossover trial, 30 consecutive NTG subjects underwent three 24-hour assessments of IOP, blood pressure (BP), heart rate (HR), and OPP [calculated according to the formula OPP = (1/3 systolic BP + 2/3 diastolic BP) x 2/3 – IOP]: at baseline, and after 1-month treatment with timolol or latanoprost. These parameters were recorded at 4 a.m., 8 a.m., noon, 4 p.m., 8 p.m., and midnight. Results Both timolol and latanoprost reduced IOP (p < 0.001), with a difference in favour of latanoprost of 1.3 mmHg (95% CI 0.9, 1.6; p < 0.001). After timolol, BP and HR decreased with respect to baseline (p < 0.001). Latanoprost increased mean OPP (3.6 mmHg, 95% CI 2.9, 4.3; p < 0.001), whereas timolol did not improve it. Conclusions Latanoprost induces an IOP reduction greater than timolol, also achieving a better circadian flattening of the IOP curve. Only latanoprost significantly increased mean 24-hour OPP. The management of Caucasian NTG patients should be critically realized, considering the 24-hour influence of each IOP-lowering drug on the ocular blood perfusion.  相似文献   
992.
BACKGROUND AND AIMS: The metabolic profile and morphologic aspects of normal and pathologic human gastric mucosa were studied. The aim of the present research was the application of ex vivo high-resolution magic angle spinning magnetic resonance spectroscopy (HR-MAS MRS) to the human gastric tissue to get information on the molecular steps involved in gastric carcinogenesis and the identification of biochemical markers useful for the development of in vivo MRS methodologies to diagnose gastric pathologies in clinical situations. METHODS: Twelve normal subjects, five with autoimmune atrophic gastritis, five with Helicobacter pylori infection, and five with adenocarcinoma were examined. Ten biopsies were taken during endoscopy from each patient. Specimens from carcinoma were also obtained during gastrectomy. Of the 10 biopsies, 4 were used for histologic evaluation, 4 were fixed in glutaraldehyde and processed for transmission and scanning electron microscopy, and 2 were immersed in liquid nitrogen and stored at -85 degrees C for monodimensional and bidimensional ex vivo HR-MAS MRS analysis. RESULTS: Ex vivo HR-MAS MRS identified glycine, alanine, free choline, and triglycerides as possible molecular markers related to the human gastric mucosa differentiation toward preneoplastic and neoplastic conditions. Ultrastructural studies of autoimmune atrophic gastritis and gastric adenocarcinoma revealed lipid accumulations intracellularly and extracellularly associated with a severe prenecrotic hypoxia and mitochondria degeneration. CONCLUSIONS: This is the first report of synergic applications of ex vivo HR-MAS MRS and electron microscopy in studying the human gastric mucosa differentiation. This research provides useful information about some molecular steps involved in gastric carcinogenesis. The biochemical data obtained on gastric pathologic tissue could represent the basis for clinical applications of in vivo MRS.  相似文献   
993.
994.
Integrin α6β4 is mostly expressed in epithelial tissues and endothelial and Schwann cells. Expression of α6β4 is increased in many epithelial tumours, implicating its involvement in tumour malignancy. Moreover, this integrin activates several key signalling molecules in carcinoma cells, but its ability to activate the phosphatidylinositol 3-kinase/Akt pathway is among the mechanisms by which α6β4 integrin regulates tumour behaviour. In this review we discuss the biological and clinical features of α6β4 integrin that allow it to promote tumour survival and progression of mammary tumours.  相似文献   
995.
PURPOSE: There is an unmet need for noninvasive markers to measure the biological effects of targeted agents, particularly those inhibiting the vascular endothelial growth factor (VEGF) receptor (VEGFR) pathway, and identify patients most likely to benefit from treatment. In this study, we investigated potential blood-based biomarkers for SU11248 (sunitinib malate), a multitargeted tyrosine kinase inhibitor, in patients with metastatic imatinib-refractory gastrointestinal stromal tumors. EXPERIMENTAL DESIGN: Patients (n=73) enrolled in a phase I/II trial received SU11248 daily for 14 or 28 days followed by 14 days without treatment per cycle. Clinical benefit was defined as progression-free survival of >6 months. We assessed plasma markers, including VEGF and soluble VEGFR-2 (sVEGFR-2), and two cellular populations bearing VEGF receptors: monocytes and, in a subset of patients, mature circulating endothelial cells (CEC). RESULTS: Compared to patients with progressive disease, patients with clinical benefit had significantly greater increases in CECs (0.52 versus -0.01 CEC/microL/d, P=0.03) and smaller decreases in monocyte levels (47% versus 60%, P=0.007) during cycle 1. VEGF increased by 2.2-fold and sVEGFR-2 decreased 25% during the first 2 weeks of treatment. Neither plasma marker correlated with clinical outcome although a modest inverse correlation was observed between sVEGFR-2 changes and plasma drug levels. Monocytes, VEGF, and sVEGFR-2 all rebounded towards baseline off treatment. CONCLUSIONS: Monocytes, VEGF, and sVEGFR-2 were consistently modulated by treatment, suggesting that they may serve as pharmacodynamic markers for SU11248. Changes in CECs and monocytes, but not the plasma markers, differed between the patients with clinical benefit and those with progressive disease. These end points merit further investigation in future trials to determine their utility as markers of SU11248 activity and clinical benefit in gastrointestinal stromal tumors and other tumor types.  相似文献   
996.
Background In advanced gastric cancer few data are available on the efficacy or safety of new drug combination regimens after progression following first-line chemotherapy. Methods Patients with histologically confirmed advanced gastric cancer and Eastern Cooperative Oncology Group (ECOG) performance status (PS) less than 2, progressing after first-line chemotherapy, were eligible. Patients were treated with docetaxel 75 mg/m2 on day 1 and oxaliplatin 80 mg/m2 on day 2, every 3 weeks, until progression or unacceptable toxicity. Results Between May 2002 and April 2005, 38 patients were enrolled. Men accounted for 73.7% of the patients and the median age was 59 years. The primary tumor was not resected in 47.4% of the patients; the peritoneum was the most frequent metastatic site (60.5%). The first-line treatment was cisplatin, epirubicin, and infusional 5-fluorouracil (ECF) in 81.5% of the patients and cisplatin and infusional 5-fluorouracil (CF) in 15.7%. The median number of cycles was 4.3. The treatment was well tolerated, with no toxic deaths. National Cancer Institute (NCI) grade III-IV neutropenia was frequent (26.3%), but no febrile neutropenia was reported. Severe asthenia (15.7%) and severe nausea (15.7%) required dose reductions in 2 patients and treatment discontinuation in another. The overall response rate was 10.5%, and 18 patients (47.3%) experienced disease stabilization (7 of them with significant clinical benefit). Median time to progression was 4.0 months (range, 2–8 months) and median overall survival was 8.1 months (range, 3–26 months). Thirteen patients (34.2%) also received third-line chemotherapy, with an irinotecan-containing regimen, and their median overall survival was higher than that of the other patients (16.3 vs 6.0 months) Conclusion The combination of oxaliplatin and docetaxel shows only marginal activity as second-line treatment, but it has a good tolerability profile. This suggests that there is room for optimizing the schedule as well as for planning sequential treatments in gastric cancer.  相似文献   
997.
PURPOSE: We assessed the relevance of Slug (SNAI2) for apoptosis resistance and invasion potential of neuroblastoma cells in vitro and in vivo. EXPERIMENTAL DESIGN: We evaluated the effect of imatinib mesylate on invasion and analyzed the genes modulated by imatinib mesylate treatment in neuroblastoma cells. Slug expression, inhibited by imatinib mesylate treatment, was knocked down in neuroblastoma cells by RNA interference, and the effects on invasion and apoptosis were evaluated in vitro. A pseudometastatic model of neuroblastoma in severe combined immunodeficient mice was used to assess the effects of Slug silencing alone or in combination with imatinib mesylate treatment on metastasis development. RESULTS: Microarray analysis revealed that several genes, including Slug, were down-regulated by imatinib mesylate. Slug expression was detectable in 8 of 10 human neuroblastoma cell lines. Two Slug-expressing cell lines were infected with a vector encoding a microRNA to Slug mRNA. Infected cells with reduced levels of Slug were tested for the expression of apoptosis-related genes (p53, Bax, and Bcl-2) identified previously as Slug targets. Bcl-2 was down-regulated in Slug-interfered cells. Slug down-regulation increased sensitivity to apoptosis induced by imatinib mesylate, etoposide, or doxorubicin. Invasion of Slug-silenced cells was reduced in vitro. Animals injected with Slug-silenced cells had fewer tumors than controls and the inhibition of tumor growth was even higher in animals treated with imatinib mesylate. CONCLUSIONS: Slug down-regulation facilitates apoptosis induced by proapoptotic drugs in neuroblastoma cells and decreases their invasion capability in vitro and in vivo. Slug inhibition, possibly combined with imatinib mesylate, may represent a novel strategy for treatment of metastatic neuroblastoma.  相似文献   
998.
Aim: Despite the paucity of controlled trials and possible interference with conventional treatments, complementary and alternative therapy (CAT) use is becoming increasingly popular and many patients do not discuss it with their physicians. Consequently, we examined the incidence and type of CAT use, perceived benefits of use, and the relationship between demographic, clinical or psychological factors and use in Western Australian patients. Methods: Two hundred newly diagnosed cancer patients beginning conventional multi‐modal treatment participated. Health‐related quality of life (HQOL), psychological adjustment and CAT use were assessed longitudinally at pretreatment, in treatment (at 8 weeks) and post‐treatment. Results: Overall, 30% of patients reported CAT use in the course of treatment. CAT users were predominantly younger (P = 0.004), tertiary educated (P = 0.016), possessed comorbid conditions (P = 0.023), and underwent lengthy treatment (P = 0.004). Patients who underwent lengthy treatment (>6 months) were three times more likely to use CAT than those who did not. Overall, 64% of CAT users perceived benefit from their use, primarily citing enhanced physical and emotional well‐being. CAT users, however, did not score significantly better than non‐users on any measure of HQOL, physical health or psychological function. CAT users generally reported greater psychosocial distress than non‐users across treatment, especially at pretreatment (baseline). However, with ongoing/new CAT use they significantly reduced their distress levels to that of non‐users by 8 weeks in treatment (P = 0.042). Conclusion: Complementary and alternative therapies enhanced cancer patients' psychological well‐being during the early stages of conventional treatment only. Use of CAT by cancer patients may be a clinical marker for psychosocial distress, and should trigger clinicians to inquire about physical symptoms, and concomitant anxiety and depression.  相似文献   
999.
1000.
OBJECTIVE: To attempt the monitoring of ovulation induction solely with ultrasound (US). DESIGN: Using serial US measurements to monitor ovulation induction using human menopausal gonadotropin and human chorionic gonadotropin (hCG), in comparison with estradiol (E2) concentrations that became available at the end of each cycle. SETTING: Specialist Reproductive Endocrine Unit. PATIENTS, PARTICIPANTS: Twenty hypogonadotropic and 29 ultrasonically diagnosed polycystic ovary patients. MAIN OUTCOME MEASURE: Follicular growth, uterine measurements, endometrial thickness, and serum E2 concentrations. RESULTS: Follicular growth, uterine measurements, and endometrial thickness correlated strongly with E2 concentrations (P less than 0.0001). The endometrium on the day of hCG administration was significantly thicker (P less than 0.01) in the conception (n = 27) compared with the nonconception cycles (n = 87), whereas no significant difference were observed in serum E2 concentrations. No pregnancy was observed when hCG had been administered when the endometrial thickness was less than or equal to 7 mm. Midluteal endometrial thickness of greater than or equal to 11 mm was found to be a good prognostic factor for detecting early pregnancy (P less than 0.008). CONCLUSIONS: Serial US examinations used alone have proven to be safe and highly efficient. It also has a unique ability to detect pregnancy in the midluteal phase.  相似文献   
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