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An attempt to improve the natural biodegradation rate in a fractured aquifer (Nardò (Le), Southern Italy) subject since '91 to the injection of 12,000 m3/d of treated municipal wastewater, has been carried out through tests on pilot plants. The lab experiments showed that a complete nitrogen removal can be realized after 10 d of infiltration in fractures by adding whey in the influent waste. The lab results have been used in a mathematical model in order to simulate ground water quality changes caused by the addition of whey in the injecting water. The analytical parameters of ground water sampled in monitoring wells located at different distances from the injection site, have been compared with mathematical model results. Moreover for preserving such resource from pollution, the mathematical model allowed two areas, around the injection site to be drawn. These areas, where withdrawals would be prohibited, are required to avoid infections by pathogens and bacteria in ground water due to incomplete biodegradation processes. The experimental results can be useful to identify standardized methodology for artificial ground water recharge which could be required for aquifer clean up (Water Frame Directive 2000/60).

Treatment, removal and recovery of lead (3 mg/L) from battery industry wastewaters have been investigated utilising a chemical precipitation process with soluble starch xanthate (SX) at pH 5-6. A reactant ratio, i.e., SX/Pb(II) = 6 mol/mol, a reaction time of 15 min., the addition of 15 mg/L of a cationic polyelectrolyte and a final filtration gave residual lead concentrations in the liquid phase less than 0.2 mg/L, well below the maximum limit established by the EU Directive. Lead was extracted from the obtained sludge by oxidation with sodium hypochlorite or hydrogen peroxide solutions. The amounts of oxidant needed were quantified as 13.5 mol NaClO/mol Pb and one order of magnitude larger, for H2O2, the latter due to the competitive disproportion reaction of the oxidant. The metal extraction was quantitative using sodium hypochlorite; when hydrogen peroxide was used, the formation of insoluble PbSO4 (Anglesite) gave a 80% metal extraction. In both cases molar ratios between sulphate and lead ions in the extracted solutions were in the range 2.1-2.2, in agreement with the stoichiometries of the reactions. Lead can be quantitatively recovered from the extracted (NaClO) solutions, for reuse, after a chemical precipitation process with 1M NaOH at pH 9-9.5, in the form of hydrocerussite [Pb3(CO3)2(OH)2].

This is the second of two papers each dealing with a specific technological option for replacing the Fenton's reagent with simpler processes for treating industrial wastewater. In particular, the paper reports the results of an investigation aimed to check, at lab scale, the effectiveness of an alternative wastewater treatment combining biological degradation and chemical oxidation with ozone. The treatment was carried out in a lab scale hybrid reactor fed with the biological stage effluent of a plant treating the wastewater of a large tanning district in Central Italy whose residual COD result still higher than the Italian COD Maximum Allowable Concentration (MAC) value (i.e., 160 mgO2/L) The results are very promising, considering that a removal efficiency of 41% (as COD) has been achieved by treating an influent characterized by a COD content fully biorefractory. In addition, the proposed treatment presents the significant advantage of no additional sludge production, as happens with commonly utilized tertiary processes (i.e. Fenton), that is characterized by high chemical sludge production.

The degradation of 5-methyl-1,3,4-thiadiazole-2-thiol (MMTD), a pharmaceutical intermediate found in some aquifers of Northern Italy, has been investigated by means of UV and UV/H2O2 treatments. The study has been carried out with a 17 W low pressure mercury lamp at room temperature, using a (100)/(1) (H2O2)/(MMTD) molar ratio. The results have demonstrated that: (i) with an initial MMTD concentration of 1 mg/l, 90% MMTD removal can be achieved within 1 hour or less than 5 minutes by UV or UV/H2O2 respectively; (ii) the sole UV irradiation does not cause any MMTD mineralization; (iii) with an initial MMTD concentration of 50 mg/l, 4 hours of UV/H2O2 treatment lead to an almost complete mineralization of the MMTD organic sulfur and to a partial mineralization of carbon (59%) and nitrogen (14%). The identification of degradation by-products, performed by HPLC-UV-MS analysis, revealed that the sole UV irradiation gives rise to the MMTD transformation into a single by-product that continuously accumulates in the solution. Conversely, the UV/H2O2 treatment forms seven intermediates that undergo further degradation through the breakdown of the thiadiazole ring. On the basis of the obtained results a degradation pathway has been proposed.

Abdominal actinomycosis is a rare disease which often resembles an acute suppurative infection or/and abdominal tumour causing abscesses, fistulas and massive fibrosis. The preoperative diagnosis is difficult and surgical exploration is always needed because of major involvement of visceral and retroperitoneal structures. The disease can be diagnosed with certainty only on the basis of findings of bacterial colonies in histopathologic sections and typical sulphur grains in secretions from fistulas. The authors describe a case of abdominal actinomycosis involving the caecum and right colon, causing extensive retroperitoneal fibrosis and a fistula tract with an external cutaneous orifice at the level of the right iliac crest. These features resembled an acute appendicitis at first, and several surgical explorations were required before a correct diagnosis could be achieved. Abdominal actinomycosis can be treated by simple administration of antibiotics. With a correct diagnosis, medical therapy alone has proved effective in a substantial percentage of patients, thus avoiding the need for surgery, if important visceral or retroperitoneal structures are not involved. Abdominal actinomycosis always requires a careful differential diagnosis and must be considered in patients presenting abdominal tumours associated with abscesses and/or fistulas since early and efficient medical therapy, along with surgical intervention, where necessary, can lead to definitive recovery. Useful diagnostic tools are abdominal CT and selective FNAB.

This is the first of two papers each dealing with a specific technological option for replacing the Fenton's reagent with simpler processes for treating industrial wastewater. In particular, the paper reports the results of an investigation aimed to check, at lab scale, the effectiveness of a chemical process (i.e., alkalinisation with or without post-ozonation) for treating tannery wastewater whose residual COD, measured after conventional biological treatment, result still higher than the Italian COD Maximum Allowable Concentration (MAC) value (i.e., 160 mgO2/L). The results have demonstrated that when the value of residual COD lies in the range 200 divided by 250 mgO2/L, a simple alkalinisation with NaOH, up to pH 12.5, allows to reach the MAC value with an alkali consumption equivalent to the acid consumption required by the Fenton treatment and with a chemical sludge production significantly lower, i.e. approximately 0.7 kg(dry)/m3 instead of approximately 1.5 kg(dry)/m3. Conversely, when the value of the residual COD lies in a higher range (i.e. 300 divided by 350 mgO2/L), in order to reach the COD MAC value, alkalinisation (from pH 8 to pH 12.5) must be followed by an ozonation post-treatment. From the chemical stand point, the paper clearly demonstrates that analyzing only simple "gross parameters" (i.e., TSS, TOC, COD, BOD5 and EC20) it is possible to get useful information about the chemical properties of the organic pollutants occurring in tannery wastewater.

Based on a rational and simple chemical approach, a field-investigation aimed to assess the role played by a natural channel "lama" on the quality of underlying groundwater and neighbouring soils has been carried out. The results have demonstrated that: (a) the stream flowing through the "lama" is mainly made up of treated effluent from a nearby municipal wastewater treatment plant; (b) the occurrence of nitrates in the "lama" is due to rain-washing of nitrogen fertilized agricultural soils bordering on the "lama"; (c) hydraulic connections exist between the lama and the underlying groundwater causing contaminants flowing through the "lama" to reach groundwater within less than one week; (d) compared with the values measured in the "lama", the concentrations of TOC, N-NH4 and N-NO3 in groundwater result: lower, far lower and greater, respectively; (e) agricultural soils bordering on the "lama" result significantly contaminated by halogenated organics.

After a previous study in which the considered oxidant was ozone (Part I), a laboratory investigation has been carried out to study the degradation of the herbicide isoproturon during its reaction with another oxidant, i.e. chlorine, in aqueous solution (Part II; this paper). The specific aim was to identify the by-products formed. The effects of pH and the presence of bromide ions were studied. Reactions have been carried out at room temperature, in phosphate buffered aqueous solutions, at four pHs (6, 7, 8 and 9). By-products identification was first performed using relatively high initial reagent concentrations which were analytically convenient ([isoproturon] = 40 mg/l, [HClO + ClO-] = 160 mg Cl/l, [Br-] = 80 mg/l). In follow-up studies, the by-products identified during this preliminary step were searched for when using concentration values closer to those actually encountered at real water treatment plants ([isoproturon] = 0.4 and 0.004 mg/l, [HClO + ClO-] = 1.6 mg Cl/l, [Br-] = 0.8 and 0.008 mg/l). Under all of the studied conditions, the results showed that isoproturon is completely degraded and that it decays much faster in the presence of bromide. The pH has a negligible influence when bromide ions are absent. On the contrary, if bromide ions are present, the isoproturon decay is slower at higher pH values. High-performance liquid chromatography-mass spectrometry (HPLC-MS) analyses have led to the identification of several by-products as a result of simultaneous oxidation and substitution reactions, both occurring on the aromatic ring of the herbicide. However, the more abundant by-products are those resulting from the oxidation of the isoproturon aromatic ring. As far as halogenated by-products are concerned, the higher the bromide ion concentration the higher the ratio of brominated to chlorinated by-products. On the basis of the analytical results, a pathway for isoproturon degradation under the studied conditions is proposed.

The degradation of the herbicide isoproturon during its ozonation in aqueous solution has been investigated with the aim of identifying intermediate as well as final by-products formed. At ambient temperature, phosphate-buffered (pH = 7) isoproturon aqueous solutions (10, 10(-1) and 10(-3) mg/l) were ozonated in a semi-batch reactor, under a continuous flow of ozonated air whose ozone concentration was 9 and 0.9 mg O3/lair for the highest and the two lower herbicide concentrations respectively. Measured steady-state ozone concentrations during the two sets of experiments (i.e. the highest and the lower isoproturon concentration) were 1.9 and 0.7 mg O3/l. Under all of the above conditions, isoproturon was always completely removed in a period ranging between 5 and 15 min, essentially by reacting with molecular ozone. High-performance liquid chromatography-mass spectrometry (HPLC-MS) analyses indicate that primary degradation by-products are formed either by introducing OH groups in the aromatic ring and/or in the side-chain substituents, or by breaking down the isopropyl alkyl chain. The results also show that these primary intermediates are successively degraded yielding low molecular weight compounds such as aldehydes, simple organic acids and alpha-oxo-acids, which have been identified by gas chromatography-electron capture detection (GC-ECD), ion chromatography (IC) and GC-MS, respectively. On the basis of the analytical results, a pathway for the degradation of isoproturon by ozone has been proposed.

The Rantox biosensor was designed for anaerobic wastewater treatment process control, and detects modifications of the feed based on the response of the acetoclastic methanogens contained in the sensor to periodic pulses of a concentrated organic substrate. The biosensor was tested under various operating conditions at the laboratory scale, in parallel with a digester under control fed on the same substrate. The aim was to evaluate the response of the biosensor in the presence of an incoming organic toxic compound (CHCl3). The experimental set-up, i.e. the biosensor and the digester, was connected to an automated control system developed under LabVIEW environment for data acquisition and operational sequence programming (the Rantox Virtual Instrument). Biomasses with different activities were used as inocula, and inhibition was induced by dosing chloroform according to two different procedures. The results showed good sensitivity and rapid response of the biosensor to feed intoxication. The presence of chloroform was detected by the Rantox with a rapid and visible response, and well in advance with respect to the digester.

Experimental studies have been carried out in a fractured coastal aquifer of the Salento Region (Nardò (Le), Italy), subject since 1991 to injection of 12,000 m3/d of treated municipal wastewater in a natural sink. The analytical parameters of ground water sampled in monitoring wells, have been compared before and after the injection started. The mound of water table (1.5 m), the reduction of seawater extent of 2 km and the spreading of pollutants injected were evaluated by means of mathematical model results. After ten years operation, the volume of the available resource for agricultural and drinking use has been increased, without notable decrease of the preexistent ground water quality. Moreover for preserving such resource from pollution, the mathematical model allowed the standards of wastewater quality for recharge to be identified. Around the sink, a restricted area was also defined with prohibition of withdrawals, to avoid infection and other risks on human health.

Chronic obstructive pulmonary disease (COPD) is characterized by lower alveolar oxygen content and hypoxia. Hypoxia itself is able to evoke a vascular reflex in a pulmonary vasoconstriction, the explanation of which is, in part, unknown. Pulmonary vasoconstriction leads to different degrees of pulmonary artery pressure (PAP) increase which statistically suggests that the higher the PAP, the poorer the survival rate. Many substances are involved in the vascular homeostasis. An important role is played by cyclooxygenase as well as lipoxygenase pathways metabolites, the antagonists of which have been extensively used in the treatment of pulmonary hypertension in subjects suffering from COPD. An even more important role is played by the endothelium. It is able to modify its metabolism towards the production of substances (e.g., endothelin, EDRF, etc.) which are able to negatively influence the vascular tone. Complete identification of such substances, when possible, would allow us to have a better understanding of the complexity of the mechanism which controls the pulmonary vascular district. In this direction we could hopefully look forward to the detection of specific new drugs able to improve the management of the disease by preventing it from worsening to that extent which statistically and drastically correlates with the worst prognosis.

Bronchoalveolar lavage (BAL) can be performed with the patient undergoing either local or general anesthesia (GA). This study investigates whether the type of anesthesia affects BAL fluid and cell recovery. Eighty patients, were selected for study. Fluid recoveries were significantly less in the GA group for both the bronchial and alveolar lavages. The differences were confirmed for BAL fluid recovery in a subsequent group of 120 unselected patients. Bronchoscope size did not appear to affect recovery, nor did anesthesia time; BAL fluid recovery from patients with respiratory failure who were intubated and mechanically ventilated was similar to that in the GA group, suggesting that lower recovery rates may be due to mechanical ventilation. The BAL fluid cell counts were related to fluid recovery, but airway neutrophils represented a higher percentage of BAL lavage fluid cells in the GA lavages, independent of differences in the volume of lavage fluid recovered.

Thirty patients undergoing epirubicin therapy for primary lung cancer were studied by echocardiography and Doppler echocardiography. 2 D ejection fraction (EF) and Doppler left ventricular filling parameters (peak E, peak A, E/A ratio) were calculated before and after the completion of therapy. No differences in the mean values of these parameters were observed. However, 6 out of 30 patients (20%) showed left ventricular filling abnormalities; in 2 of them a slight reduction of EF was also noted. These abnormalities seem to be dose related. A longer term prospective study will be required to evaluate whether these findings are irreversible and to establish the clinical implications of our observations.

To assess the smoking cessation efficacy of transdermal nicotine patches an adjunct to low-intervention therapy, we conducted a double-blind, placebo-controlled trial in 158 smokers. Participants were randomly assigned to one of the following three study regimens that required daily application of two 15-cm2 patches: 1) 24-hour nicotine delivery, 2) nicotine delivery during wakeful hours only, and 3) placebo. The impact of the three regimens on smoking cessation rates and tobacco withdrawal symptoms was examined. During the last 2 weeks of the trial, 39% of the 24-hour nicotine regimen delivery group, 35% of those on wakeful hour nicotine regimens, and 13.5% of the placebo treatment group achieved abstinence. Self-reported quit rates for the two nicotine patch-wearing regimens, as compared with that for the placebo group, continued to be significantly higher at 6 months. Moreover, compared with placebo, the transdermal nicotine patches significantly reduced tobacco withdrawal symptoms during the first few weeks of quitting. The differences in quit rates and tobacco withdrawal symptoms between the to active groups were not statistically significant. The patches were well tolerated both topically and systemically. We concluded that transdermal nicotine, when used as an adjunct to low-intervention therapy, significantly reduced tobacco withdrawal symptoms and enhanced smoking cessation rates.

The AA. report the results of an experimental investigation on 60 subjects who underwent surgery for advanced stage carcinoma of the glottic larynx and treated with alpha 2b recombinant interferon at the dosage of 3,000,000 ul three times a week, before a six-months follow-up. The patients were examined also as to the respiratory functionality and the monitoring of some biological markers of cancers (CEA, TPA, Ca 125, Ca 15.3). The AA. support the satisfactory tolerability of alpha interferon which showed expected side effects; these effects were controlled by the symptomatic treatment, and their metabolic parameters as well as the ones related to the respiratory functionality kept always their valves in the average. The monitoring of biological markers, seems to support a real usefulness in the treatment with alpha interferon, even if a statistically meaningful record couldn't be noticed.

Bronchoalveolar lavage (BAL) is a widely used clinical procedure. To determine if BAL could provide useful information in the detection of cancer, 850 lavages from 421 patients having BAL for a variety of indications, 50 lavages in patients with Hodgkin's disease and 20 patients with breast cancer undergoing bon marrow transplant were reviewed. BALs were performed with the technique established by Rennard and coll. in which 5 successive 20 cc aliquots are infused in a wedge position. The return from the first aliquot was processed separately from the subsequent four aliquots. Diff-Quick stained cytocentrifuge preparations and Papanicolaou stained millipore filter preparations were analyzed. Thirty-five patients had biopsy-proven lung cancer. In 24 (68.6%) of these, BAL revealed cells diagnostic of malignancy. There were no false positives. Six out of 50 Hodgkin's disease patients had Reed Sternberg cells detected on BAL, and 7/20 breast cancer patients had malignant cells on BAL prior to chemotherapy. In summary, the routine performance of BAL, an easily performed and well-tolerated procedure, may prove to be useful in the routine assessment of patients for cancer.

Monoclonal antibodies detection represented a turning point in field of immunological and biological research. Their application has rapidly extended at immunopathology as well as immunodiagnosis and immunotherapy fields. In oncological field monoclonal antibodies has proved a great usefulness in diagnosis of several districts neoplasm. Monoclonal antibodies are utilized in differential diagnosis of different histologic types of lung cancer; in bone marrow metastasis early detection; and, experimentally, in "in vivo" diagnosis of lung cancer via peripheral blood sample examination. Authors relate about more recent literature about this specific topic.

Thymidine kinase (TK) is a biological marker recently used in diagnosis and monitoring of pulmonary and mediastinal malignant neoplasms. Authors report more recent clinical evidences of literature and, in the meanwhile, they report their personal experiences about a 20 patients group suffering of lung cancer and Hodgkin disease. Their study demonstrates a good sensitivity of TK as biological marker of SCLC and a lower sensitivity in case of NSCLC and Hodgkin disease. It has been possible to contribute to establishment of normal range values, on account of 10 healthy volunteer group blood sample assays.

Eighteen patients were examined by Doppler echocardiography before and after treatment with doxorubicin (DXR). Early left ventricular filling rate decreased from 66 +/- 15 to 51 +/- 10 cm/sec whereas late filling rate increased from 48 +/- 12 to 61 +/- 9 cm/sec (p less than 0.05) with inversion of the E/A ratio suggesting an impairment of left ventricular diastolic function; conversely no significant changes were found in systolic function indexes. These results suggest that follow-up of patients treated with DXR must include left ventricular diastolic function studies. Doppler echocardiography can be successfully used to detect the presence of diastolic abnormalities.