Coupling membrane separation and photocatalytic oxidation processes for the degradation of pharmaceutical pollutants

The coupling of membrane separation and photocatalytic oxidation has been studied for the removal of pharmaceutical pollutants. The retention properties of two different membranes (nanofiltration and reverse osmosis) were assessed. Comparable selectivity on the separation of pharmaceuticals were observed for both membranes, obtaining a permeate stream with concentrations of each pharmaceutical below 0.5 mg L⁻¹ and a rejected flux highly concentrated (in the range of 16–25 mg L⁻¹ and 18–32 mg L⁻¹ of each pharmaceutical for NF-90 and BW-30 membranes, respectively), when an initial stream of six pharmaceuticals was feeding to the membrane system (10 mg L⁻¹ of each pharmaceutical). The abatement of concentrated pharmaceuticals of the rejected stream was evaluated by means of heterogeneous photocatalytic oxidation using TiO₂ and Fe₂O₃/SBA-15 in presence of hydrogen peroxide as photo-Fenton system. Both photocatalytic treatments showed remarkable removals of pharmaceutical compounds, achieving values between 80 and 100%. The nicotine was the most refractory pollutant of all the studied pharmaceuticals. Photo-Fenton treatment seems to be more effective than TiO₂ photocatalysis, as high mineralization degree and increased nicotine removal were attested. This work can be considered an interesting approach of coupling membrane separation and heterogeneous photocatalytic technologies for the successful abatement of pharmaceutical compounds in effluents of wastewater treatment plants.     

Influence of environmental temperatures on the concrete compressive strength: Simulation of hot and cold weather conditions

The objective of this work is to study the influence of mixing hour on the properties of concrete, such as workability and compressive strength, under hot and cold weather conditions, with a view to industrial application. The variable focused on was the concrete mixing hour, and five different mixing hours were used for each type of weather condition. Three batches of concrete were prepared for each mixing hour, and the compressive strength of 15 cylindrical concrete specimens was measured after 7 and 28 days. In addition, the hydration kinetics of each batch of concrete was studied on the basis of the climatic conditions and the mixing hour. The results for compressive strength show that the concrete's best mechanical performance occurred when there was the least difference between ambient temperature and concrete temperature, that is, during the later hours of the day in hot weather conditions.     

In vitro lipolytic effect of leptin on mouse adipocytes: evidence for a possible autocrine/paracrine role of leptin

The present study has examined the effects of the adipocyte-derived hormone, leptin, on lipolysis in fat cells of different types of mice. Exposure to leptin (1.25.10(-6) M to 1.25.10(-12) M) increased (P < 0.01) the lipolytic activity of fat cells obtained from lean mice. A greater stimulation was observed when adipocytes from ob/ob mice were examined. Throughout the concentrations tested, the leptin-induced lipolysis observed in fat cells of lean animals was smaller than that obtained in ob/ob mice. The maximal lipolytic effect in obese animals was observed with 10(-8) M of OB protein. The lipolytic activity following the addition of 1.25.10(-10) M to 1.25.10(-6) M was significantly increased (P < 0.01) in ob/ob mice compared to lean animals. Adipocytes from ob/ob mice responded in a dose-dependent manner to the OB protein, while the leptin-induced lipolysis observed in lean animals was dose-independent. In contrast to lean and ob/ob mice, leptin did not stimulate lipolysis in adipocytes from db/db mice, which have a mutation in the leptin receptor gene. These in vitro studies suggest an autocrine/paracrine action of leptin on white fat cells and envisages the involvement of the OB protein, not only in centrally mediated pathways, but also in physiological functions which take place peripherally.     

Intentions and behaviors of risky drug consumption in users at the rehabilitation centers in Valencia]

Several criteria have been used for differentiating hepatic cavernous hemangioma from other tumors at magnetic resonance imaging (MRI). Included are signal intensity and lobulation of the tumor. We counted the frequency of presence of lobulation of liver hemangiomas on T2-weighted images (T2WI), and measured the signal-intensity ratio (SIR) on T1-weighted images (T1WI) and on T2WI with a 0.9 mm x 0.9 mm pixel size using a 0.5 T magnetic resonance system. Eighty-three cavernous hemangiomas in 44 patients and 67 malignant tumors in 44 patients were retrospectively studied. Seventy-five of the cavernous hemangiomas (90%) exhibited lobules of various sizes, and four of the malignant tumors (6%) exhibited lobulations. The cavernous hemangiomas had a significantly higher SIR than the malignant tumors on T2WI: 3.0 +/- 0.7 and 1.9 +/- 0.8 (p < 0.001), respectively. The presence of lobulation together with a high SIR was a useful measure for differentiating cavernous hemangiomas from other liver tumors.     

Treatment of cyclosporin-induced gingival hyperplasia with azithromycin

BACKGROUND: Gingival hyperplasia is a known complication of cyclosporin therapy. Although plaque control has been shown to be of benefit, gingival surgery is occasionally necessary. The aim of this study was to review the effect of a short-course therapy with azithromycin in renal transplant patients with cyclosporin-induced gingival hyperplasia. METHODS: Thirty-eight patients received 500 mg/day of azithromycin for 3 consecutive days. The degree of gingival hyperplasia was classified as: 0, no gingival overgrowth; 1, mild overgrowth; 2, moderate overgrowth, and 3, severe overgrowth. Gingival bleeding and evolution of gingival hyperplasia were determined at 0 (pretreatment), 7, 30, 90 and 180 days. Cyclosporin, serum creatinine and ALT levels were simultaneously determined on the same days. RESULTS: Seven patients were excluded, leaving a total of 31 included in the trial. Eleven had a score of 3, 17 a score of 2, and 3 a score of 1. The degree of gingival hyperplasia was unrelated to the dose and levels of cyclosporin. Gingival hyperplasia improved in all patients (P < 0.001, Friedman test). The degree of improvement was better when the degree of hyperplasia was lower. In 27 patients gingival hyperplasia remained absent 6 months later, 3 patients required a second course of treatment, and another required gingival surgery. Gingival bleeding, present in 28 patients when diagnosed, disappeared in all cases in 2.2 +/- 1.2 (1-7) days. No adverse effects were observed. Cyclosporin, serum creatinine, and ALT levels were not affected by treatment. CONCLUSIONS: Azithromycin improves cyclosporin-associated gingival hyperplasia, especially when administered early in the process.     

Reaggregation and binding of cell wall proteins from Candida albicans to structural polysaccharides

Urea or hot sodium dodecyl sulphate extracted a significant amount of the same proteins from the matrix of the cell wall of the yeast form and mycelial cells of Candida albicans. Gel filtration analysis of the urea-extracted proteins revealed that they occurred in the form of large complexes which were unaffected by up to 8 M urea. Among them, proteins en route to becoming covalently associated within the wall scaffold were identified by their reaction with specific antibodies. When urea was removed by dialysis, some of these proteins specifically reassociated into large aggregates which bound strongly with ConA, whereas others remained soluble in smaller associated products. The ability of some of these proteins to bind to the insoluble wall polysaccharides was also assessed. No self-assembling proteins were able to bind to glucans and/or chitin. Specificity of the binding to polysaccharides made of beta-bound glucosyl or N-acetylglucosaminyl residues was determined by the competitive effect of several disaccharides. Whereas laminaribiose and diacetylchitobiose were strong inhibitors of protein binding to both glucan and chitin, lactose, maltose and sucrose were ineffective.     

Biofunctionality of MBCP ceramic granules (TricOs™) plus fibrin sealant (Tisseel®) versus MBCP ceramic granules as a filler of large periprosthetic bone defects: an investigative ovine study

We aimed to quantify bone colonization toward an untreated titanium implant with primary stability following filling of the defect with micromacroporous biphasic calcium phosphate (MBCP) granules (TricOs?) or MBCP granules mixed with fibrin sealant (Tisseel^®). Medial arthrotomy was performed on the knees of 20 sheep to create a bone defect (16 mm deep; 10 mm diameter), followed by anchorage of a titanium screw. Defects were filled with TricOs or TricOs–Tisseel granules, a perforated MBCP washer, a titanium washer and titanium screw. Sheep were euthanized at 3, 6, 12 and 26 weeks. From Week 12 onwards, the percentage of bone in contact with the 8 mm anchorage part of the screw increased in both groups, confirming its primary stability. At 26 weeks, whereas bone colonization was similar in both groups, biodegradation of ceramic was more rapid in the TricOs–Tisseel group (P = 0.0422). The centripetal nature of bone colonization was evident. Bone contact with the titanium implant surface was negligible. In conclusion, the use of a model that reproduces a large metaphyseal bone defect around a titanium implant with primary stability, filled with a mixture of either TricOs ceramic granules or TricOs granules mixed with Tisseel fibrin sealant, suggests that the addition of fibrin to TricOs enhances bone filling surgical technology.     

Mechanical characterisation of traditional adobes from the north of Spain

Mud is one of humankind’s oldest construction materials. The paper presents a technical study of straw-stabilized adobe, prepared in the traditional manner using wooden frames and compacting the mixture manually. The mud is selected from a specific area in the province of León (Spain) where adobes had been employed traditionally from long years ago using two different proportions of straw: 25% and 33% of total volume. The laboratory tests have followed the standard EN protocols. The different tests developed were of two types: for the natural soil granulometric analysis, relative density and Atterberg limits were made; for the adobes the following were done: shrinkage during drying, density, compressive and flexural strength.Results show an average compressive strength of 3.8 N/mm² and an average flexural strength of 0.68 N/mm², so it can be stated that traditional adobes can be used as an adequate construction material.     

Determination of parameters used to prevent ignition of stored materials and to protect against explosions in food industries

There are always risks associated with silos when the stored material has been characterized as prone to self-ignition or explosion. Further research focused on the characterization of agricultural materials stored in silos is needed due to the lack of data found in the literature. The aim of this study was to determine the ignitability and explosive parameters of several agricultural products commonly stored in silos in order to assess the risk of ignition and dust explosion. Minimum Ignition Temperature, with dust forming a cloud and deposited in a layer, Lower Explosive Limit, Minimum Ignition Energy, Maximum Explosion Pressure and Maximum Explosion Pressure Rise were determined for seven agricultural materials: icing sugar, maize, wheat and barley grain dust, alfalfa, bread-making wheat and soybean dust. Following characterization, these were found to be prone to producing self-ignition when stored in silos under certain conditions.