Toxic response of the bacterium Vibrio fischeri to sodium lauryl ether sulphate residues in excavated soils.

Sodium lauryl ether sulphate (SLES) is the main chemical component in several lubricant products used for soil conditioning in the mechanized excavation industry using Earth Pressure Balance-Tunnel Boring Machines. During the tunnelling process, huge amounts of excavated soil are produced and the SLES presence can affect the subsequent re-use of this material as a by-product. Currently, there is still no regulatory indication of reliable and sensitive bioassays for monitoring soil quality during the excavation process. The main objective of this work was to verify if the Vibrio fischeri screening test was suitable as a consistent and precautionary tool for this specific purpose. Firstly, the ecotoxicity (EC20 and EC50) of the SLES standard solution and three commercial products (SLES content from 10 to 50%) were evaluated to select the most environmental friendly product. Subsequently, soil samples from about 2 years of tunnelling in a real construction site, conditioned with the selected product, were evaluated for their environmental compatibility with the prescriptions of an Italian site-specific protocol. The latter established 2 mg/L as a threshold value for SLES concentration in soil water extracts and a no toxic response (≤20%) for the Vibrio fischeri test. The comparison of the bacterium bioluminescence inhibition values (%) with analytical determinations showed an ecotoxicity when SLES was >2 mg/L. The toxicity was directly related to SLES concentration, indicating that the V. fischeri test and the SLES analyses are suitable tools for assessing excavated soil as a by-product, ensuring its safe reuse in accordance with a green production process (circular economy).

Zinc and cadmium removal by biosorption on Undaria pinnatifida in batch and continuous processes.

Zn(II) and Cd(II) removal by biosorption using Undaria pinnatifida was studied in batch and dynamic systems. The kinetic uptake follows a pseudo second order rate equation indicating that the rate limiting step is a chemical reaction. The equilibrium data are described by the Langmuir isotherm in mono-component solutions. In binary solutions, the Jain and Snowyink model shows that most of the active sites are exclusively accessible to cadmium ions without competition with the zinc ions. The dynamic studies show that the biosorbent has higher retention and affinity for Cd(II) than for Zn(II) in both mono- and bi-component systems. SEM-EDX analysis indicates that the active sites are heterogeneously distributed on the cell wall surface. FT-IR spectrometry characterization shows that carboxylic groups and chemical groups containing N and S contribute to Zn(II) and Cd(II) uptake by U. pinnatifida. According to these results calcium-treated U. pinnatifida is a suitable adsorbent for Zn(II) and Cd(II) pollutants.

Zinc and cadmium biosorption by untreated and calcium-treated Macrocystis pyrifera in a batch system.

Zinc and cadmium can be efficiently removed from solutions using the brown algae, Macrocystis pyrifera. Treatment with CaCl(2) allowed stabilization of the biosorbent. The maximum biosorption capacities in mono-component systems were 0.91 mmol g(-1) and 0.89 mmol g(-1) and the Langmuir affinity coefficients were 1.76 L mmol(-1) and 1.25 L mmol(-1) for Zn(II) and Cd(II), respectively. In two-component systems, Zn(II) and Cd(II) adsorption capacities were reduced by 50% and 40%, respectively and the biosorbent showed a preference for Cd(II) over Zn(II). HNO(3) (0.1M) and EDTA (0.1M) achieved 90-100% desorption of both ions from the loaded biomass. While HNO(3) preserved the biomass structure, EDTA destroyed it completely. Fourier transform infrared spectra identified the contribution of carboxylic, amine and sulfonate groups on Zn(II) and Cd(II) biosorption. These results showed that biosorption using M. pyrifera-treated biomass could be an affordable and simple process for cadmium and zinc removal from wastewaters.

Fungal bioremediation of creosote-treated wood: a laboratory scale study on creosote components degradation by Pleurotus ostreatus mycelium.

A bioremediation system for creosote-treated wood is proposed, based on the detoxifying capability of Pleurotus ostreatus, a ligninolythic fungus. Non-sterilized chipped contaminated wood was mixed at various ratios with wheat straw on which Pleurotus mycelia was grown. At 1:2 initial ratio contaminated wood:wheat straw, chemical analyses demonstrated an almost complete degradation of creosote oil components after 44 days, also confirmed by a significant reduction of ecotoxicity. Lower ratios, i.e. higher amount of contaminated wood, lower system efficiency, although a better creosote degradation was obtained by a stepped up wood addition.

Integrated bacterial process for the treatment of a spent nickel catalyst.

Integrated biological processes involving the dissolution and subsequent precipitation have been used for the treatment of the spent material from the hydrogenation of vegetable oil containing a high-level of nickel. Our results show that nickel was successfully leached using Acidithiobacillus thiooxidans. The percentages of nickel leached using A. thiooxidans were higher than those obtained with dilute sulphuric acid solutions. Due to the physical characteristics of the residue, the best results were obtained when the leaching process was carried out using sulphuric acid biogenerated by an A. thiooxidans biofilm. The recovery of nickel from the leachates was performed at room temperature by precipitating with sulphide generated by Desulfovibrio cells. Indirect precipitation using sulphide generated in Desulfovibrio sp. cultures allowed the recovery of nickel as the very insoluble nickel sulphide.

Spinal dysraphism in an elderly patient.

Spinal dysraphisms are diagnosed more frequently at birth or in infancy. We report a spinal malformation compatible with lipomyeloschisis in an elderly patient presenting with symptoms and signs of myelopathy. Magnetic resonance imaging revealed an intraspinal mass continuous with a subcutaneous lipoma. Three-dimensional computed tomography reconstructions better showed the spinal dysraphism; dermal sinus was also evident. Neuroimaging can define the precise diagnosis also in elderly patients presenting with myelopathy and can provide valuable structural details.

Iron-oxidizing and leaching activities of sulphur-grown Thiobacillus ferrooxidans cells on other substrates: effect of culture pH.

The rate of iron (II) oxidation by sulphur-grown Thiobacillus ferrooxidans cells decreased when the pH of the original growth medium was lowered. This behaviour was observed even after shifting from the original growth pH to a higher pH. After being suspended in medium at a pH higher than the growth pH, sulphur-grown cells could leach covellite at a similar initial rate to iron-grown cells. Sulphur-grown cells exhibited a long lag phase when the original growth pH was low. These results were correlated with the number of protons associated with the cell surface, rather than with cell hydrophobicity or cell capacity to attach to solid particles. Sulphur-grown cells grown in very acidic media (without pH control) were not able to oxidize iron (II) or leach covellite even after shifting to a high pH.

Bio-dissolution of spent nickel-cadmium batteries using Thiobacillus ferrooxidans.

In this study, the production of sulphuric acid in bioreactors with Thiobacillus ferrooxidans attached on elemental sulphur was investigated. These bioreactors reached a maximum H+ productivity of 80 mmol kg-1 d-1 of support. This medium was used for the indirect dissolution of spent nickel-cadmium batteries recovering after 93 days 100% of cadmium, 96.5% of nickel and 95.0% of iron. Moreover, recoveries higher than 90.0% were reached when anodic and cathodic materials were directly added to Thiobacillus ferrooxidans cultures with sulphur as the sole energy source. The results presented show an economic and effective method which could be considered the first step to recycle spent and and discarded batteries preventing one of the many problems of environmental pollution.

Adrenalectomy reduces FGF-1 and FGF-2 gene expression in specific rat brain regions and differently affects their induction by seizures.

We have previously reported that limbic seizures regulate the gene expression of fibroblast growth factor-2 (basic, FGF-2) according to a specific spatio-temporal pattern. In the present paper we have investigated the role of adrenal hormones on seizure-induced elevation of fibroblast growth factor-1 (acidic, FGF-1) and FGF-2 gene expression. Adrenalectomy reduces FGF-2 mRNA expression in specific brain regions, such as frontal cortex, hippocampus and striatum, whereas FGF-1 mRNA levels were decreased only in the frontal cortex. The injection of kainic acid in adrenalectomized rats produced a widespread increase of FGF-2 mRNA with a pattern similar to sham animals as indicated by in situ hybridization. In contrast, although kainate-induced elevation of FGF-1 mRNA in the hippocampus was not influenced by adrenalectomy, its induction in frontal cortex was prevented by this surgery procedure. Taken together, these data indicate that adrenal hormones play a role in the regulation of the gene expression for fibroblast growth factors, but different mechanisms are operative in their induction following seizure activity.

A practical technique for conformal simulation in radiation therapy of pelvic tumors.

PURPOSE: A radiological procedure, based on straightforward conventional methods, was used for a demonstration of pelvic anatomy during simulation to precisely delineate the target volume and increase the probabilities of pelvic tumor control. METHODS AND MATERIALS: Between 1990 and 1993, 450 patients with primary pelvic malignancies underwent external radiotherapy by means of photons, 6-10 MeV, with multiple-field techniques. The simulation was carried out immediately following a pelvic organs opacification (POO) by standard methods. This procedure used a minimal quantity of contrast media (barium sulphate, iodine contrast) and metallic markers to locate directly and simultaneously: (a) small intestine, (b) bladder, (c) rectum, (d) anal canal, (e) bulbous male urethra, and (f) vagina. When all these structures were clearly visualized, the procedure was scored as successfully performed. RESULTS: The sensitivity of procedure was defined as the percentage of successful pelvic organs opacification (POO) carried out in the patients. It was 98% in both women and men. Indirectly, the procedure helped us to locate the prostate, the perineum, and the uterus cervix in the same percentage of patients. Pelvic organs opacification allowed us to document not only the normal position of the pelvic organs tested, but also any variations (ranging from 5% to 40% of cases, after pelvic surgery). Furthermore, POO revealed previously not-reported abnormalities in patients undergoing surgery, mostly rectal stenosis, urinary or anal incontinence, and bladder luxation. The cost of the materials used was $10-15 for each POO, and the time required 5-7 min. The side effects were 7% and not significant. CONCLUSION: In the simulation phase for multiple-field irradiation technique, the simultaneous visualization of pelvic organs obtained by POO procedure allows an exact positioning of the isocenter, an accurate shielding of structures, and finally, a reliable conformal therapy. Due to the low cost, the short length, and the insignificant side effects, POO can be carried out more than once during pelvic treatments for localization and verification of target.

Bioleaching of metallic sulphides withThiobacillus ferrooxidans in the absence of iron (II).

Bioleaching of metallic sulphides withThiobacillus ferrooxidans in the absence of iron (II) was studied using pure sulphides and mixtures. The direct mode of bacterial action was analysed with respect to sulphide solubility, exposed solid surfaces and bacterial attachment to the solids. Bioleaching of mixed sulphides showed enhancement of metal extraction in comparison with pure sulphides which suggests metal extractions would be better from polymetallic sulphide ores than from similar matrices with only one sulphide.

Comparison of results with CO2 laser and traditional surgical treatment of stage I malignant melanoma.

The follow-up data on 39 cases of stage I malignant melanoma treated with CO2 laser are compared to those of an analogous group of cases treated by traditional surgical methods and selected for their clinical and pathologic similarities with the laser-treated group. The findings were expressed in terms of tumor-free time and were evaluated by variance analysis. The data showed that traditional methods gave better results. CO2 laser surgery requires longer healing time, which may have a negative effect on the course of the disease.

Phenotypic and ultrastructural profile of M5 leukemia cells in peripheral blood and skin infiltrate.

The leukemic cells circulating in the peripheral blood and invading the skin of a patient with type M5 myelomonocytic leukemia were compared using ultrastructural, cytochemical and immunological criteria. Neoplastic cells exhibited more differentiated morphologic features in the skin than in peripheral blood, resembling tissue macrophages. The cytochemical pattern did not show any appreciable difference, whereas the surface antigenic profile was dissimilar. Most circulating leukemic cells were Leu M1+ and Leu M3+, and the percentage of OKM1+ and OKIa-1+ cells varied in two different blood samples examined. Conversely, OKIa-1 monoclonal antibody stained virtually all the leukemic cells infiltrating the skin in the absence of any appreciable reactivity with the other monoclonal antibodies. The phenotype of the malignant cells in the skin did not vary during the clinical course of the disease. These observations suggest that the cutaneous microenvironment is able to induce leukemic cells to mutate their phenotypic features towards a more mature state, or that only relatively differentiated circulating leukemic cells are able to leave the bloodstream and colonize the skin.

An ultrastructural study of a sclerosing epithelial hamartoma.

The histological and ultrastructural features of a sclerosing epithelial hamartoma are described. By electron microscopy, epithelial cords formed by basal-like cells and epithelial cysts with a pattern of keratinization similar to that of normal epidermis or of follicular infundibula were seen. By conventional light microscopy, continuities were found between the epithelial cords and the overlying epidermis. The stroma was found to be fibrous and contained some fibroblasts or possibly myofibroblasts with bundles of microfilaments. The data are interpreted with respect to the origin of the neoplasm, its line of differentiation, and its sclerosing behavior.

[Laboratory contribution to the diagnosis of micromolecular myeloma. Description of 5 cases]. / Contributo del laboratorio alla diagnosi di mieloma micromolecolare. Descrizione di 5 casi.

Five cases of micromolecular myeloma, discovered with systematic electrophoretic study of proteinurias, are described. Technical details useful for diagnosis are discussed.

[Radiotherapy of brain metastases. Presentation of 104 cases examined by computerized axial tomography]. / Radioterapie delle metastasi cerebrali. Presentazione di 104 casi studiati con tomografia assiale computerizzata.

104 patients suffering from brain metastases and treated by whole brain irradiation have been studied with computerized tomography before and after radiation therapy. Brain computerized tomography is increasingly helpful and reliable in determining the location of metastases and regression of disease; it is too a more reliable source of information than neurologic examination in the evaluation of prognosis. Results of our study show that radiation therapy achieves an effective palliation and may be considered the most helpful therapeutic method of such patients; it really relieves symptoms relating to brain metastases and allows a longer survival in a fairly good number of patients.