Proficiency of some synthetic alginate derivatives for sequestration of Iodine-131 from radioactive liquid waste.

The current effort in environmental remediation is aimed at removing iodine-131 radionuclide from radioactive liquid waste produced by an Egyptian nuclear power plant using some synthesised alginate derivatives. Two different copolymers, namely sodium alginate poly (acrylic acid) (P1) and sodium alginate poly (acrylic acid-methacrylic acid) (P2), are prepared using gamma radiation. The ability of these polymers to remove 131I radionuclide as sorbents has been investigated. The synthesised polymers exhibit excellent adsorption performance for 131I ions, and the adsorption equilibrium requires only 30 min, which reveals that the sorption process is kinetically faster than most of the other materials reported previously. The removal percents for 131I radionuclide at a pH of 3.0 at room temperature on P1 and P2 are 77.7% and 84.2%, respectively. The sorption capacities of the two polymers demonstrate that P2 > P1, with capacities of 67.9 and 58.5 mg/g, respectively. Four linear kinetic models are investigated: pseudo-first order, pseudo-second order, Elovich, and Weber-Morris models. Regarding their calculated parameters, these models indicate that the adsorption process of I-ions on both P1 and P2 is controlled by chemisorption. Four equilibrium isotherm models (Redlich-Peterson, Langmuir, Freundlich, and Harkin-Jura) are investigated, revealing that the adsorption process is a monolayer and multilayer process on a heterogeneous surface.

The evolving role of radiofrequency ablation therapy of breast lesions.

BACKGROUND: The potential for radiofrequency ablation (RFA) therapy is an area of increasing interest in the context of breast conserving therapy for breast cancer. This non surgical technique potentially provides a non invasive, cosmetically pleasing result that is preferable to surgeon and patient. MATERIALS AND METHODS: A literature review was carried out facilitated by PubMed and Medline databases. Cross referencing of the obtained articles was used to identify other relevant studies. A total of 17 studies were reviewed. RESULTS: RFA is emerging as a promising treatment for breast cancer. Pilot and phase II studies have shown RFA to be effective at ablation with few complications or adverse effects experienced by patients. However, complete ablation of tumours is still not achieved in all patients. CONCLUSION: RFA represents a promising therapeutic modality for breast lesions. However, there is a clear need for further research and refinement of the procedure before it can be offered as a therapeutic alternative to surgical excision for operable breast cancer.

Surgical excision for B3 breast lesions diagnosed by vacuum-assisted core biopsy.

UNLABELLED: The aim of this retrospective study was to assess whether open surgical excision is required following a B3 diagnosis on 11-gauge vacuum-assisted core biopsy (VACB) of radiologically indeterminate breast lesions. PATIENTS AND METHODS: Twenty-four women with a histological diagnosis of the B3 category on VACB of radiologically indeterminate breast lesions were identified over a 3-year period. The VACB procedure was performed under stereotactic (n=21), ultrasound (n=2) or magnetic resonance imaging (MRI) (n=1) guidance using the Suros system. Nineteen patients underwent open surgical excision. The remaining 5 patients who had 'complete' removal of the radiological abnormality using VACB under ultrasound (n=2, papilloma) or stereotactic (n=4, atypical ductal hyperplasia) guidance were followed up clinically and radiologically. RESULTS: The median patient age was 49 years. The disease status in three patients was upgraded to ductal carcinoma in situ at open surgical excision. The VACB showed atypical lobular hyperplasia in these 3 patients, associated with microcalcification (n=2) or mass lesion (n=1). No single case of upgrading to invasive breast cancer was identified in our series. The remaining patients (16 out of 19) had a benign biopsy. The upgrade to malignancy was significantly associated with the presence of atypical lobular hyperplasia, a BI-RADS category of 4 and incomplete removal of the radiological abnormality by VACB. After a mean follow-up of 18 months, no malignancy was detected in the 5 patients who did not undergo open surgical biopsy. CONCLUSION: Open surgical excision is strongly recommended for atypical lobular hyperplasia identified in VACB specimens. VACB can be a safe alternative to surgery in the treatment of B3 lesions in selected cases, providing thorough multidisciplinary discussion has taken place.

Evidence of a tumour suppressor function for DLEC1 in human breast cancer.

UNLABELLED: DLEC1 (deleted in lung and oesophageal cancer), located on 3p22.3, is a candidate tumour suppressor gene in lung, esophageal, and renal cancer. The aim of this study was determine whether the mRNA expression levels of DLEC1 were consistent with a tumour suppressive function. MATERIALS AND METHODS: A total of 153 samples were analysed. The levels of transcription of DLEC1 were determined using quantitative PCR and normalised against (CK19). Transcript levels within breast cancer specimens were compared to normal background tissues. RESULTS: Levels of transcription were lower [corrected] in tumour samples compared to adjacent non cancerous tissue (ANCT) samples but this was not statistically significant (median 0.167 vs. 0.03; p=0.138). DLEC1 expression levels were significantly lower in samples from patients who developed metastasis, local recurrence, or died of breast cancer when compared to those who were disease free for >10 years (p=0.041). DISCUSSION: These findings are consistent with a possible tumour suppressor function of DLEC1 in breast cancer.

Characterization of phosphogypsum wastes associated with phosphoric acid and fertilizers production.

The present work is directed to characterize the phosphogypsum (PG) wastes associated with phosphoric acid produced by the wet process in industrial facility for the production of fertilizers and chemicals in Egypt. The PG waste samples were characterized in terms of spectroscopic analysis (X-ray diffraction, X-ray fluorescence, IR spectra) and radiometric analysis (gamma- and alpha-measurements). The gamma-ray measurements showed that the average activity concentrations are 140+/-12.6, 459+/-36.7, 323+/-28.4, 8.3+/-0.76 and 64.3+/-4.1 Bq/kg for U-238, Ra-226, Pb-210, Th-232 and K-40, respectively. The alpha-particle measurements of uranium isotopes showed that the average activity concentrations of U-238, U-235 and U-234 were 153+/-9.8, 7+/-0.38, 152+/-10.4 Bq/kg, respectively. The average radiochemical recovery (%) of the destructive alpha-particle measurements is approximately 70% with a resolution (FWHM) of approximately 30 keV. Activity ratios of U-238/Ra-226 and U-238/Pb-210 were less than unity (i.e., <1) and equal to 0.31+/-0.02 and 0.47+/-0.16, respectively. The isotopic ratios of U-238/U-235 and U-238/U-234 (in PG and PR samples) were close to the normal values of approximately 21.7 and approximately 1, respectively and are not affected by the wet processing of phosphate rock (PR). The obtained results of PG waste samples were compared with phosphate rock (PR) samples. The radiation hazard indices are namely, radium activity index (Ra-Eq>370 Bq/kg), total absorbed gamma dose rate (D(gamma r)>5 nGy/h) and radon emanation fraction (Rn-EF>20%). Uncertainty of the sample counting was 95% confidence level of sigma. The results indicated the necessity to find suitable routes to decrease and/or redistribute the radionuclide of environmental interest (i.e., Ra-226) in PG wastes, consequently to reduce its radiation impacts in the surrounding environment.

Modeling of gadolinium recovery from nitrate medium with 8-hydroxyquinoline by emulsion liquid membrane.

The extraction equilibrium of Gd(III) from nitrate medium by 8-hydroxyquinoline (HOX) in toluene was studied. Liquid-liquid investigations were first carried out. Based on the equilibrium results, the extraction of Gd(III) from aqueous nitrate medium into an emulsion liquid membrane system (ELM) containing 8-hydroxyquinoline in toluene as extractant, HNO(3) as stripping solution, Span-80 as surfactant was studied. The stability of the prepared ELM was studied in terms of the degree of membrane breakage. The different parameters affecting the permeation of gadolinium (III) were also studied. A general permeation model for the recovery of Gd(III) by the selected membrane is presented. The internal mass transfer in the water in oil (W/O) emulsion drop, the external mass transfer around the drop, the rates of formation and decomposition of the complex at the external aqueous-organic interface were considered.