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Different Endpoints (different + endpoint)
Selected AbstractsSubchronic organismal toxicity, cytotoxicity, genotoxicity, and feeding response of pacific oyster (Crassostrea gigas) to lindane (,-HCH) exposure under experimental conditionsENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 10 2007Gerardo Anguiano Abstract This study evaluated organismal toxicity, cytotoxicity, and genotoxicity and the filtration rate in response to different concentrations of subchronic lindane (gamma-hexachlorocyclohexane [,-HCH]), exposure (12 d) in adult Pacific oysters Crassostrea gigas. Oysters were exposed in vivo in laboratory aquaria to 10 different concentrations (0.0,10.0 mg/L) of ,-HCH. The median lethal concentration (LC50) after 12 d was calculated as 2.22 mg/L. Cytotoxic effects were observed in hemocytes, where the mean cell viability was significantly decreased at 1.0 mg/L of ,-HCH after 12 d. Genotoxicity of ,-HCH measured by single cell gel electrophoresis assay, in hemocytes was evident at 0.7 mg/L of ,-HCH after 12 d. After 4 h of exposure to ,-HCH, filtration rates were reduced compared with controls to 65.8 and 38.2% at concentrations of 0.3 and 0.7 mg/L, respectively, and after 11 d of exposure, filtration rates were reduced to 60.4 and 30.9% at concentrations of 0.1 mg/L and higher. These results show the subchronic effects of ,-HCH at different concentrations and effect sensitivities are categorized as filtration rate < genotoxicity < cytotoxicity < mortality. The relevance of integral toxicity evaluation, considering different endpoints from molecular, cellular, and individual levels is discussed. [source] The influence of pH and salinity on the toxicity of heavy metals in sediment to the estuarine clam Ruditapes philippinarum,ENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 5 2004Inmaculada Riba Abstract An approach is presented for determining the influence of two key variables, pH and salinity(S), on the toxicity of four common heavy metals bound to sediments in estuaries. Two samples of environmental sediment taken from two estuaries in southern Spain (the Huelva estuary and the Guadalquivir River estuary), together with a dilution of toxic mud from the Aznalcóllar (Spain) mining spill (April 1998) were used to determine their toxicity at different values of pH (6.5, 7.5, and 8.5) and salinity (10, 20, and 30) on the estuarine clam Ruditapes philippinarum. Two different endpoints, sublethal, indicated by clam reburial (median effective burial time [ET50]), and relative mortality (median lethal concentration [LC50]), were used to quantify the toxicity associated with the heavy metals. Neither salinity nor pH was found to influence the toxic responses measured by the behavioral endpoint (ET50). However, a strong effect on the LC50 related to pH and salinity was detected, with the toxicity of the heavy metals being increased at low values of both variables (pH = 6.5 and S = 10). The mechanism of heavy metals uptake through water may explain this influence of pH and salinity on the lethal toxicity detected. The results show differences in the toxicity of these heavy metals bound to sediments depending on whether the origin of metal contamination is chronic or acute. [source] Clinical value of p53, c-erbB-2, CEA and CA125 regarding relapse, metastasis and death in resectable non-small cell lung cancerINTERNATIONAL JOURNAL OF CANCER, Issue 5 2003Marina Pollán Abstract The prognostic value of p53 and c-erbB-2 immunostaining and preoperative serum levels of CEA and CA125 was investigated in a prospective multicentric study including 465 consecutive non-small cell lung cancer (NSCLC) patients with resectable tumors. Four end-points were used: lung cancer death, first relapse (either locoregional or metastasis), loco-regional recurrence and metastasis development. Standard statistical survival methods (Kaplan-Meier and Cox regression) were used. The specificity of the prognostic effect across different types of tumors was also explored, as had been planned in advance. Our results showed, once again, that pathological T and N classifications continue to be the strongest predictors regarding either relapse or mortality. Three of the studied markers seemed to add further useful information, however, but in a more specific context. For example, increased CEA concentration defined a higher risk population among adenocarcinomas but not among people with squamous tumors; and p53 overexpression implied a worse prognosis mainly in patients with well differentiated tumors. The analysis of type of relapse proved to be very informative. Thus, CA125 level was associated with a worse prognosis mainly related with metastasis development. Another interesting result was the influence of smoking, which showed a clear dose-response relationship with the probability of metastasis. For future studies, we recommend the inclusion of different endpoints, namely considering the relationship of markers with the type of relapse involved in lung-cancer recurrence. They can add useful information regarding the complex nature of prognosis. © 2003 Wiley-Liss, Inc. [source] Endoscopic ultrasound-guided fine-needle aspiration for the diagnosis of solid pancreatic masses: the impact on patient-management strategyALIMENTARY PHARMACOLOGY & THERAPEUTICS, Issue 10 2009Y. TOUCHEFEU Summary Background, Endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) is a safe and accurate technique for diagnosing pancreatic cancer. However, its impact for management of these patients is poorly investigated. Aims, To investigate the diagnostic yield and the therapeutic impact of EUS-FNA in the management of solid pancreatic masses. Methods, One hundred consecutive patients who underwent EUS-FNA for a solid pancreatic mass were included. Aspirates were placed onto glass slides for cytological examination and microbiopsies were fixed in formaldehyde for histology. The impact on clinical management was analysed retrospectively according to different endpoints, such as its impact on indications for chemotherapy, surgery or appropriate follow-up modality. Results, Eight procedures were considered failures and two patients were lost to follow-up. A final diagnosis was obtained in 90 patients. The sensitivity, specificity and accuracy of combined cytology and histology for the diagnosis of malignant or potentially-malignant tumours were 78%, 75%, and 78% respectively. The sensitivity and accuracy of cytology alone were significantly higher than those of histology alone (P = 0.0003). By intention-to-diagnose analysis, EUS-FNA directly influenced the management strategy in 62 of 100 patients. Conclusions, In patients with pancreatic mass and suspected malignancy, EUS-FNA provides an accurate diagnosis in approximately 80% of cases. EUS-FNA directly influences the management in two-thirds of patients. [source] | ||||||||||