Ozone photolysis of paracetamol in aqueous solution.

The degradation of a paracetamol (N-acetil-para-aminofenol) aqueous solution (C (0) P = 5 mmol L(-1)) is studied in a bench-scale setup by means of simple ozonation (O3) and ozonation catalyzed with UV light (O3/UV) in order to quantify the influence of UV light on the degradation process. The results have shown that under the adopted experimental conditions (25°C, applied ozone dose = 9.8 mg L(-1) and gas flow rate of 20 L h(-1)) both oxidative systems are capable of removing the substrate with mineralization degrees up to 51% for ozonation and 53% for O3/UV. HPICE chromatography allowed the detection of nitrate ions and maleic and oxalic acids as ultimate carboxylic acids. The experimental data have been interpreted through 5 indicators: the conversion of paracetamol (XP ), the conversion degree of TOC (XTOC ), the apparent rate constant (kap ), the Hatta number (Ha) and the enhancement factor (E). The main advantage of photo-ozonation compared to simple ozonation was a more advanced conversion (79% vs. 92% after 90 min). The paracetamol decay follows a pseudo-first-order reaction with a superior rate constant (higher by 54%) for the UV catalyzed system in comparison with direct ozonation. Mineralization is slightly accelerated (+4%) in the O3/UV system, due to the additional production of hydroxyl radicals induced by the UV light and a higher Hatta number (+24%). Nevertheless, the process was still in the slow reaction kinetic regime (Ha < 0.3), and the enhancement factor was not significantly increased. The results are useful for the design and scale-up of the gas-liquid processes.

Comparison of different advanced oxidation processes for the degradation of two fluoroquinolone antibiotics in aqueous solutions.

In this study a comparative assessment using various advanced oxidation processes (UV/H(2)O(2), UV/H(2)O(2)/Fe(II), O(3), O(3)/UV, O(3)/UV/H(2)O(2) and O(3)/UV/H(2)O(2)/Fe(II)) was attempted to degrade efficiently two fluoroquinolone drugs ENR [enrofloxacin (1-Cyclopropyl-7-(4-ethyl-1-piperazinyl)-6-fluoro-1,4-dihydro-4-oxo-3-quinolonecarboxylic acid)] and CIP [ciprofloxacin (1-cyclopropyl-6-fluoro-4-oxo-7-(piperazin-1-yl)-quinoline-3-carboxylic acid)] in aqueous solutions at a concentrations of 0.15 mM for each drug. The efficiency of the applied oxidation processes (AOPs) has been estimated by the conversion of the original substrate (X(ENR) and X(CIP)) and the reduction of chemical oxygen demand (COD), total organic carbon (TOC). Special emphasis was laid on the effect of varying reaction pH as well as of the applied oxidant doses on the observed reaction kinetics for each advanced oxidation processes. High degradation efficiencies, particularly in terms of rates of TOC and COD abatement, were obtained for photo-Fenton assisted ozonation [O(3)/UV/H(2)O(2)/Fe(II)], compared to other advanced oxidation processes. At pH 3 and 25°C best results for the degradation of both investigated drugs were achieved when 10 mM H(2)O(2), 0.5 mM Fe(II) and an initial dose of 8.5 mg L(-1) ozone were applied. In addition, the evolution of toxicity of the reaction mixtures for different AOPs has been studied by the bioluminescence test (LUMIStox 300).

Asymptomatic urinary anomalies, hematuria and proteinuria, in patients with inflammatory bowel disease. Preliminary study.

The study assesses the presence of asymptomatic urinary anomalies in patients with inflammatory bowel disease. Asymptomatic urinary anomalies are mainly due to glomerular nephritis, they being one of the forms of its manifestation, together with chronic nephrotic and nephritic syndromes. We identified urinary anomalies in 18 patients (20%) with bowel inflammatory disease that consisted of haematuria in 8 (9%) patients, isolated proteinuria in 5 (6%) patients and haematuria associated with proteinuria in 5 (6%) patients. Asymptomatic urinary anomalies were more frequent in patients with the Crohn disease than in those with ulcerative colitis. We identified RFG under 60ml/min in 4 patients with asymptomatic urinary anomalies. It is very easy to evaluate asymptomatic urinary anomalies with dipstick. This method is also required in current practice for patients with urinary anomalies for identifying the glomerular disease that might have caused them. One must take into consideration differential diagnosis with other diseases that can manifest themselves with proteinuria or isolated proteinuria. One must also take into account the fact that urinary anomalies may also be related to administration of 5-aminosalicylates.

Elements of renal injury in patients with varicose ulcer. Preliminary study.

The kidney may be affected in the processes of microbial, viral, parasitic infections. Knowledge of renal disease during chronic infection, with a different location than the throat, is of particular importance for the practicing physician for the detection and prevention of impaired renal function. Chronic kidney disease recovered in the early stages can prevent the progression of renal function decline. We studied a total of 85 patients with varicose ulcers with a mean age of 66.78 +/- 12.09 years, hospitalized in the Clinic of Dermatology and a control group consisting of 110 apparently healthy individuals. Urinary abnormalities have been detected in 26 (30%) of patients studied. GFR < 60 ml/min have been detected in 14 (17%) of patients studied. CRF stage II have been detected in 36 (42%) of patients studied. We detected recurrent varicose ulcer in 2 (2%) of patients studied. In two (2%) of patients during hospitalization we found a decrease in GFR by 15 and 12 ml/min, accompanied by an increase in serum creatinine from 0.7 mg % to 1 mg % in one patient and in another patient from 1.5 mg % to 2 mg %. Urinary abnormalities detected in patients with both acute and recurrent erysipelas warn about renal impairment and the need for monitoring of the renal patients with varicose ulcers.

Elements of renal injury in patients with erysipelas.

Erysipelas is an infectious disease caused by group A beta hemolytical streptococci which may produce renal lesions, most frequently glomerular disease. Renal injury although known is less studied in practice. Rarely bioptical exams have been performed, thus the problem of the relationship erysipelas glomerular disease is practically not solved. The aim of this study was a cross-sectional analysis of renal involvement produced by erysipelas in two departments where patients with erysipelas are diagnosed and treated: Dermatology and Infectious Diseases. We investigated 166 patients (86M, 80F; mean age 61.66 +/- 18.42) with erysipelas hospitalized in the Departments of Dermatology (55 patients-33%) and Infectious Diseases (111 patients-66%) during 2005-2009. The diagnosis was established on clinical and biological data. In these patients clinical and biological exam has been performed. We assessed GFR and urinalysis (hematuria and proteinuria). The control group consisted of 110 apparently healthy persons. Of the 166 patients with erysipelas we found asymptomatic urinary abnormalities in 82 (47%), isolated proteinuria in 19 (11%) patients and proteinuria associated with hematuria in 21 (13%) patients, and isolated hematuria in 38 (23%) patients. We did not find patients with nephrotic or nephritic syndrome. In the control group we found asymptomatic urinary abnormalities in 25 (23%) of the patients. A statistically significant difference was between the two groups (p < 0.01). Asymptomatic urinary abnormalities have been more frequent in patients with erysipelas from the Infectious Diseases Department compared to those from the Dermatology Department. A statistically significant difference has been found (p < 0.03). In patients with recurrent erysipelas (43 patients-26%) we found asymptomatic urinary abnormalities in 26 (54%) of the patients compared to the presence of asymptomatic urinary abnormalities in patients with acute erysipelas in 56 out of 123 (46%). Mean GFR in patients with erysipelas was of 73.94 +/- 27.79 ml/min. It was lower in patients with recurrent erysipelas, 72.13 +/- 24.74 mL/min respectively. Association of proteinuria with hematuria was more frequent in patients with recurrent erysipelas. Patients with asymptomatic urinary abnormalities during the course of erysipelas need to be closely monitored during antibiotic treatment.

Short communication controlling LC-SPE-NMR systems.

There are several stages of the LC-SPE-NMR process that should be monitored closely to ensure an efficient isolation and concentration of the target analyte, for instance analyte break-through and compound transfer from the LC-SPE to the NMR probe. In this study, analyte break-through monitoring was performed with a UV detector and a mass spectrometer placed after the SPE unit. Easy break-through was a problem when attempting multiple trapping of various compounds using C18 SPE cartridges with the original commercial system. However, on lowering the flow rate over the SPE system and using SPE cartridges packed with porous carbon, the number of trappings possible increased five-fold. To increase control over the on-line SPE-NMR transfer, a gradient pump-UV system was used to elute compounds trapped on an SPE to an NMR probe. The analyte band was placed in the active volume of the probe by a stop-flow mechanism. The modified LC-SPE system was also coupled with off-line NMR analysis for determination of a degradation product of the insecticide monuron, present in the low ppm range.

Comparison of advanced oxidation processes and identification of monuron photodegradation products in aqueous solution.

The photodegradation of monuron (3-(4-chlorophenyl)-1,1-dimethylurea) in aqueous solutions under simulated solar irradiation has been conducted by different advanced oxidation processes (UV/H(2)O(2), UV/H(2)O(2)/Fe(2+), UV/H(2)O(2)/TiO(2), UV/TiO(2), dark H(2)O(2)/Fe(3+)). The degradation rates were always higher for the homogeneous catalysis in photo-Fenton reactions (UV/H(2)O(2)/Fe(2+)) compared to the heterogeneous photocatalytic systems (TiO(2)/UV and UV/H(2)O(2)/TiO(2)). Optimal concentrations of Fe(2+) and H(2)O(2) for the abatement of the herbicide in the photo-Fenton system were found to be 1 mM Fe(II) and 10 mM H(2)O(2). Several intermediary products were identified using large volume injection micro-liquid chromatography with UV detection (mu-LC-UV), mu-LC-MS and GC-MS techniques and a degradation mechanism has been proposed.