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Biomedical subjects

G Ziglio

Publications and source records attributed to G Ziglio.

17 recordsLinked to original sources
PubMed2002

Biomass active fraction evaluated by a direct method and respirometric techniques.

The knowledge of the active biomass amount and its characterisation is of primary importance for the management and for the design of wastewater treatment plants on the basis of the recently developed models. OUR curves obtained in aerobic exponential growth tests are proposed by several authors as an indirect method to estimate the active fraction. The aim of this work is the application of a direct method to measure the viable biomass based on flow cytometry techniques and the comparison with the active fraction obtained from respirometric tests. To assess the viable fraction of a biomass expressed in terms of COD concentration it is necessary to estimate the biovolume of viable bacteria and to know the specific carbon content per cell. For the investigated activated sludge samples, the bacterial biomass measured by FCM was 588 mgCOD L(-1) on average in a two-months period. This value of active fraction corresponds to 14% of particulate COD. Active biomass values measured with the respirometric approach were consistent but generally higher than those obtained by FCM.

Biomass↗
PubMed2002

A comparison among different methods for evaluating the biomass activity in activated sludge systems: preliminary results.

In order to improve activated sludge plant operation (achieving higher efficiency and cost savings) beside influent and effluent characteristics and working parameters (e.g. dissolved oxygen, total and volatile suspended solids, pH, recirculation flow rate, etc.), the biomass activity should be monitored, the bacteria being responsible for the pollutant degradation. Since conventional cultivation based methods are inadequate to quantify environmental microorganisms (due to scarce number of cultivable microorganisms and time-consuming procedures) several "non-conventional" techniques were applied in this study, in order to compare the obtainable information and their routine feasibility. Different measurements (VSS concentration, Oxygen Uptake Rate, microbial counts by cultural and biomolecular methods--MPN-PCR, ATP content, dehydrogenase activity, microbial cell viability and enzymatic activity) were carried out on mixed liquor samples, taken from a municipal activated sludge plant (440,000 p. e.). The preliminary results of the research are presented in this paper.

Adenosine Triphosphate↗
PubMed2001

Experimental validation of a single-OUR method for wastewater RBCOD characterisation.

Wastewater characterisation is of primary importance for the correct design and management of a treatment plant. The aim of this work was the evaluation of a new rapid and easy to use respirometric technique for the characterisation of readily biodegradable COD (RBCOD). When the necessary calibration curve is obtained, the RBCOD assessment procedure needs less than 30 minutes. On the contrary, conventional techniques require some hours. The first step consists in calculating a calibration curve in order to point out the correlation between oxygen consumed and known amount of added Sodium Acetate. To a well aerated biomass (in order to remove residual readily biodegradable substrate) a known amount of Sodium Acetate is added and the related OUR is measured. The oxygen consumed (delta DO) is related to the added COD (as Sodium Acetate). Therefore, the RBCOD concentration in wastewater samples can be obtained according to the following steps: (1) measure delta DO; (2) multiply delta DO by the Volume of aerated mixed liquor used in the test; (3) from the calibration curve, calculate the readily biodegradable COD equivalent to Acetate; (4) estimate RBCOD concentration multiplying the wastewater sample volume tested in the reactor. Some advantages of this technique are described in the paper.

Algorithms↗
PubMed1994

Selection and evaluation of recipients for heart-lung and lung transplantation: the Niguarda Hospital experience.

Between January 1989 and February 1993, 52 patients were evaluated at Niguarda Hospital for lung or heart and lung transplantation. Of the 35 that entered the waiting list, a total of 19 were transplanted (14 at other institutes before our surgical programme became operative, and 5 at our hospital). Recipient selection and evaluation criteria, and timing of transplantation in the different diseases are discussed.

Contraindications↗
PubMed1992

A gas-chromatographic determination of the ppb levels of volatile halogenated hydrocarbons in water for injections.

Some volatile halogenated hydrocarbons have been found in commercial large volume parenterals (LVPs) prepared from untreated or treated (disinfected) water. To monitor the presence of volatile halogenated hydrocarbons in the source water and also in the water for injections, a low cost and sufficiently simple procedure has been developed, specifically for the following components: 1,1,1 trichloroethane, 1,1,2 trichloroethylene, 1,1,2,2 tetrachloroethylene, carbon tetrachloride, chloroform, dichlorobromomethane and dibromochloromethane. A Head-space technique coupled with ECD-gaschromatography was used. The procedure is thoroughly discussed in the article, including the results of a ring test for a preliminary validation of this method.

Chromatography, Gas↗
PubMed1985

Metabolites of chlorinated solvents in blood and urine of subjects exposed at environmental level.

After a two-level selection, 141 blood donors living in Milan, Italy, were analyzed for their content of plasma and urinary trichloroacetic acid (TCA) and trichloroethanol (TCE). Environmental levels of exposure to trichloroethylene (TRI) and tetrachloroethylene (PER) through drinking water and air were also measured. The plasma TCA levels were in the range of previously found concentrations. Relationships among plasma and urinary metabolites were found and discussed.

Adolescent↗
PubMedDate not supplied

Terbinafine in the treatment of non-immunocompromised compassionate cases of bronchopulmonary aspergillosis.

Conventional treatments of broncho-pulmonary aspergillosis are often ineffective and result in associated side-effects. Terbinafine (a new allylamine derivative), although as active against Aspergillus in vitro as amphotericin B and itraconazole, is less effective in rodent models because of a rapid hepatic first-pass effect. As terbinafine is metabolized differently in humans, the aim of this work was to evaluate this drug, for the first time, in the treatment of seven immunocompetent patients with lower respiratory tract mycotic infections unresponsive to the usual antimycotic drugs. Diagnosis was based on identification of fungal isolates, worsening of respiratory function tests, chest radiographs and computerized tomographic (CT) scan changes, positive skin test, aspergillin precipitins and clinical history. Terbinafine was administered at doses ranging from 5 to 15 mg kg-1 day-1 depending on the clinical severity of the disease, and was given for 90-270 days depending on clinical progress and compliance. In three patients A. fumigatus was suppressed with resolution of signs and symptoms; four patients showed transitory A. fumigatus suppression with marked clinical and radiological improvement. During relapses no resistance to terbinafine was observed. No significant side-effects were detected. Terbinafine appeared to be as effective as amphotericin B and itraconazole in the treatment of bronchopulmonary aspergillosis in nonimmunocompromised patients. These preliminary results suggest that controlled studies are warranted.

Adult↗