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1.
Environ Sci Pollut Res Int ; 29(32): 49161-49178, 2022 Jul.
Article in English | MEDLINE | ID: mdl-35217956

ABSTRACT

Cesium-137, as the main fission product, is of special interest in the marine environment because of its solubility, which results to very low sinking time. Nevertheless, the conservative form of the main percentage of 137Cs introduced in the marine environment (70%) makes 137Cs to be included in the salinity of sea water. Based on this property, in this study, we examine potential relations between 137Cs activity concentrations and marine parameters issued from Earth Observation (EO) data products in the Southern Aegean Sea, in order to investigate the possibility of 137Cs to be recorded by satellite data. In particular, measurements of physical and biological marine parameters issued from the Copernicus Marine Environment Monitoring Service (CMEMS) database and MODIS ocean products are retrieved for the dates of 137Cs field measurements. Single and multiple regression analyses are performed between the marine parameters and 137Cs activity concentration measurements for three distinctive time periods (total, cold, and warm period). The best results are obtained from multiple regressions, one for each time period (r2 > 0.70). The models show that during cold period, 137Cs activity concentrations are highly correlated to both chlorophyll and nutrients (phosphates) while during warm and the total period, they seem to be mainly correlated to the photosynthetic available incident solar radiation on the sea surface. For each period, we propose a multiparameter model linear in its parameters. Although the results of this study must be considered preliminary due to the limited size of the datasets, for the first time, we show that estimations of 137Cs activity concentrations from EO measurements and CMEMS environmental models are feasible, and they can be used as a marine radiological assessment tool for a closed Mediterranean bay such as Souda Bay in Greece.


Subject(s)
Radiation Monitoring , Water Pollutants, Radioactive , Bays , Cesium Radioisotopes/analysis , Greece , Water Pollutants, Radioactive/analysis
2.
Radiat Environ Biophys ; 56(4): 443-451, 2017 11.
Article in English | MEDLINE | ID: mdl-28776193

ABSTRACT

The substantial complexity in ecosystem-radionuclide interactions is difficult to be represented in terms of radiological doses. Thus, radiological dose assessment tools use typical exposure situations for generalized organisms and ecosystems. In the present study, site-specific data and radioactivity measurements of terrestrial organisms (grass and herbivore mammals) and abiotic components (soil) are provided. The retrieved data are used in combination with the ERICA Assessment Tool for calculation of radiological parameters. The process of radionuclide transfer within ecosystem components is represented using concentration ratios (CRs), while for the calculation of dose rates the dose conversion coefficient (DCC) methodology is applied. Comparative assessments are performed between the generic and assessment-specific radiological parameters and between the resulting dose rates. Significant differences were observed between CRs calculated in this study and those reported in the literature for cesium and thorium, which can easily be explained. On the other hand, CRs calculated for radium are in very good agreement with those reported in the literature. The DCCs exhibited some small differences between the reference and the assessment-specific organism due to mass differences. The differences were observed for internal and external dose rates, but they were less pronounced for total dose rates which are typically used in the assessment of radiological impact. The results of the current work can serve as a basis for further studies of the radiological parameters in environments that have not been studied yet.


Subject(s)
Biota/radiation effects , Radiation Monitoring/methods , Animals , Radiobiology , Soil , Soil Pollutants, Radioactive
3.
Eur J Gastroenterol Hepatol ; 21(5): 529-33, 2009 May.
Article in English | MEDLINE | ID: mdl-19373973

ABSTRACT

OBJECTIVES: To study the effect of pentoxifylline and octreotide administration on serum levels of TNF-alpha and IL-6, in patients who underwent endoscopic retrograde cholangiopancreatography (ERCP), whether they developed pancreatitis or not. METHODS: Out of 590 patients undergoing ERCP, 30 who developed pancreatitis and 25 who did not (controls) were enrolled. Pentoxifylline was given to 23 patients (15 with and eight without pancreatitis) and octreotide to 19 patients (nine with and 10 without pancreatitis, respectively). Thirteen patients did not receive any preventive medication (six with and seven without pancreatitis, respectively). Blood samples were collected at baseline, 6 and 24 h after ERCP. RESULTS: IL-6 increased significantly in patients with pancreatitis at the 6 h (4.2 pg/ml SD: 5.8) and at the 24 h (6.6 pg/ml SD: 9.8) compared with patients without pancreatitis at the 6 h (2.1 pg/ml SD: 3.6) and 24 h (1.9 pg/ml SD: 2.5) (P < 0.01). No significant difference in the values of TNF-alpha and IL-6 obtained among the three study groups in patients with or without pancreatitis was observed. TNF-alpha levels at the 24 h were lower than baseline in patients with pancreatitis who received octreotide (P = 0.04). CONCLUSION: IL-6 increased in the first 24 h of post-ERCP pancreatitis. Pentoxifylline and octreotide cannot prevent IL-6 elevation but octreotide reduces TNF-alpha levels, which may have an impact on the severity of post-ERCP pancreatitis.


Subject(s)
Cholangiopancreatography, Endoscopic Retrograde/adverse effects , Interleukin-6/blood , Octreotide/therapeutic use , Pancreatitis/etiology , Pentoxifylline/therapeutic use , Tumor Necrosis Factor-alpha/blood , Acute Disease , Adult , Aged , Biomarkers/blood , Female , Gastrointestinal Agents/therapeutic use , Humans , Inflammation Mediators/blood , Male , Middle Aged , Pancreatitis/prevention & control , Tumor Necrosis Factor-alpha/drug effects
4.
Gastrointest Endosc ; 66(3): 513-8, 2007 Sep.
Article in English | MEDLINE | ID: mdl-17725940

ABSTRACT

BACKGROUND: Pentoxifylline can ameliorate pancreatitis in animal models because of its anti-tumor necrosis factor properties. OBJECTIVE: Our purpose was to study the safety and efficacy of pentoxifylline in the prevention of post-ERCP pancreatitis. DESIGN: Patients due to undergo ERCP for various indications were randomized to receive pentoxifylline 400 mg orally 3 times, beginning the day before ERCP (2 and 10 pm) until the night after the procedure (6 am and 2 and 10 pm) or to receive no preventive medication. Serum amylase values were determined before and 6 and 24 hours after ERCP. Diagnosis and grading of the severity of complications was performed according to consensus criteria. PATIENTS: One hundred fifty-eight patients received pentoxifylline (group A) and 162 had no medication (group B). The groups were similar in distributions of sex, biliary sphincterotomy, pancreatography, pancreatic duct cannulations, stone extraction, stent placement, and presence of periampullary diverticulum. Group A patients were younger (mean age 63 vs 68 years, P<.05) and biliary colic was a more frequent indication (30 vs 12, P<.05). RESULTS: Nine (5.6%) patients in group A and 5 (3%) in group B had pancreatitis (2 and 1 severe, respectively; P=.28). Serum amylase values were similar in baseline and 6- and 24-hour samples. Two (1.2%) patients in group A and 7 (4.3%) in group B had hemorrhage. LIMITATIONS: This was not a double-blind trial. CONCLUSIONS: In this study pentoxifylline did not protect against post-ERCP pancreatitis or hyperamylasemia.


Subject(s)
Bile Duct Diseases/therapy , Cholangiopancreatography, Endoscopic Retrograde/adverse effects , Pancreatitis/prevention & control , Pentoxifylline/therapeutic use , Premedication , Aged , Bile Duct Diseases/diagnosis , Female , Humans , Hyperamylasemia/prevention & control , Male , Middle Aged , Sphincterotomy, Endoscopic/adverse effects
5.
Exp Hematol ; 34(11): 1583-7, 2006 Nov.
Article in English | MEDLINE | ID: mdl-17046578

ABSTRACT

For end-stage liver disease, liver transplantation provides the only definite cure; however, many patients die while in the waiting list for donation. Various stem cell populations have been described to contribute to liver regeneration and there is accumulating evidence for the participation of hematopoietic stem cells (HSCs) in this process. We here report two cases treated with boost infusions of autologous mobilized HSCs to regenerate cirrhotic liver. The procedure was safe and well tolerated. Both patients showed a lasting amelioration in the clinical course of the disease during the 30 months of follow-up. These results suggest that the procedure may be considered in a clinical study setting as a bridging therapy until organ transplantation becomes available or to reverse a decompensated cirrhosis to a compensated one. Additional studies in this area will be required to document efficacy and evaluate toxicity.


Subject(s)
Liver Cirrhosis, Alcoholic/therapy , Peripheral Blood Stem Cell Transplantation , Biopsy , Follow-Up Studies , Humans , Immunohistochemistry , Infusions, Intravenous , Liver Cirrhosis, Alcoholic/diagnosis , Liver Cirrhosis, Alcoholic/pathology , Male , Middle Aged , Peripheral Blood Stem Cell Transplantation/adverse effects , Recovery of Function , Transplantation, Homologous , Treatment Outcome
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