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Biomedical subjects

G D'Ascenzo

Publications and source records attributed to G D'Ascenzo.

At least 19 recordsLinked to original sources
PubMed2005

Role of extracorporeal photochemotherapy in patients with refractory chronic graft-versus-host disease.

Recent studies suggest that extracorporeal photochemotherapy (ECP) may be beneficial in patients with steroid-refractory chronic graft-versus-host disease (cGvHD). However, it is not yet clear whether certain conditions, such as age, mode of onset of cGvHD etc., influence clinical response and whether certain affected organs are more sensitive to ECP than others. We analysed the main clinical and laboratory parameters related to evolution of the disease in 32 steroid-refractory cGvHD patients, to identify any useful response predictors to ECP. ECP affected the course of the disease positively in 78% (25/32) of our cases.

Adult↗
PubMed2003

Fate of natural estrogen conjugates in municipal sewage transport and treatment facilities.

The aim of this study was to investigate the fate of the conjugated forms of the three most common natural estrogens in the municipal aqueous environment. Levels of conjugated and free estrogens in (1) female urine; (2) a septic tank collecting domestic wastewater; (3) influents and effluents of six activated sludge sewage treatment plants (STPs) were measured. The analytical method was based on solid-phase extraction by using a Carbograph 4 cartridge and Liquid Chromatography-tandem Mass Spectrometry. On average, a group of 73 women selected to represent a typical cross section of the female inhabitants of a Roman condominium, excreted 106, 14 and 32 microg/day of conjugated estriol (E(3)), estradiol (E(2)) and estrone (E(1)), respectively. Apart from some E(3) in pregnancy urine, free estrogens were never detected in urine samples. Estrogen sulfates represented 21% of the total conjugated estrogens. This situation changed markedly in the condominium collecting tank. Here, significant amounts of free estrogens were observed and the estrogen sulfate to estrogen glucuronated ratio rose to 55/45. A laboratory biodegradation test confirmed that glucuronated estrogens are readily deconjugated in unmodified domestic wastewater, presumably due to the large amounts of the beta-glucuronidase enzyme produced by fecal bacteria (Escherichia coli). Deconjugation continued in sewer transit. At the STP entrance, free estrogens and sulfated estrogens were the dominant species. The sewage treatment completely removed residues of estrogen glucuronates and with good efficiency (84-97%) the other analytes, but not E(1) (61%) and estrone-3-sulfate (E(1)-3S) (64%). Considering that (1) E(1) has half the estrogenic potency of E(2), (2) the amount of the former species discharged from STPs into the receiving water was more than ten times larger than the latter one and (3) a certain fraction of E(1)-3S could be converted to E(1) in the aquatic environment, E(1) appears to be the most important natural endocrine disrupter.

Adolescent↗
PubMed2003

Extracorporeal photochemotherapy in the treatment of eosinophilic fasciitis.

BACKGROUND: Eosinophilic fasciitis (EF) is a rare connective tissue disorder characterized clinically by symmetrical swelling, induration and thickening of the skin and histologically by thickening of the fascia with chronic inflammatory infiltrate containing eosinophils. The disease is classified in the spectrum morphea/systemic sclerosis and treated with systemic steroids and other immunosuppressant drugs. OBJECTIVE: The purpose of this study was to use extracorporeal photochemotherapy (ECP) in patients with EF to evaluate the effectiveness of this therapy. SUBJECTS AND METHODS: Three patients affected by EF were treated with ECP because they failed to respond or with contraindications to immunosuppressant treatment. The patients underwent ECP with a UVAR XTS apparatus. Subjects were treated on two consecutive days at 2-week intervals for the first 3 months and thereafter every 4 weeks on the basis of clinical response. The patients were assessed before therapy and then monthly by means of a clinical score. Changes in affected areas were evaluated at predetermined points by computerized skin elastometry (Cutometer SEM 474). RESULT: After 1 year of therapy we found considerable improvement of clinical parameters in two cases. There was less striking improvement in the other case. These clinical results were confirmed by the elastometry measurements. All patients reported improved quality of life, which enabled a reduction in the dose of immunosuppressants. CONCLUSION: ECP emerged as a safe and effective therapy in association with low doses of immunosuppressants in our three patients. A randomized comparative multicentre study between ECP as single therapy and ECP plus immunosuppressants and conventional therapies is required to firmly establish photopheresis as a possible basic treatment to combine with conventional therapies for EF.

Adrenal Cortex Hormones↗
PubMed1999

Chemical analysis of water of the Anticolana Valley: isolation of humic compounds.

The purpose of this study was to identify and characterize humic compounds in Anticolana Valley (Fiuggi) water. The capacity of this class of compounds to mobilize metals from solid phases could have an important role in calculi solubilization. Humic compounds were isolated, purified and characterised by FTIR, 1H-NMR and 13C-NMR spectroscopy, thermogravimetry and elemental analysis. Only fulvic acids were found. They are mainly composed of aliphatic chains, made of six -CH2O- groups and contain a number of carboxylic groups, responsible for their metal complexing capacity.

Benzopyrans↗
PubMed1999

Solvent effect in vitro of Anticolana Valley water on renal stones: analytical-instrumental study.

The presence of humic and fulvic acids in the Anticolana Valley (Fiuggi) water has been established. On the basis of this evidence we investigated the capacity of Anticolana Valley (Fiuggi) water to dissolve renal calculi in vitro. Crystals of calcium oxalate monohydrate to simulate a kidney stone were prepared. Human renal stones of calcium oxalate monohydrate were obtained by courtesy of the Division of Urology of 'La Sapienza' University (Rome), the Division of Urology of the University of Havana (Cuba) and the ASTIF of Fiuggi. The study was performed using the Anticolana Valley (Fiuggi) water, distilled water and tap water (ACEA, Rome), in a specially designed Perspex apparatus. Each calculus was subjected to a water flow of 2 liters/24 h. The capacity of the Anticolana Valley (Fiuggi) water to dissolve human and synthetic calculi was found to be much higher than that of distilled water which in turn was significantly more effective than tap (ACEA) water.

Calcium Oxalate↗
PubMed1998

Determination of arylphenoxypropionic herbicides in water by liquid chromatography-electrospray mass spectrometry.

A very sensitive and specific analytical procedure for determining arylphenoxypropionic herbicides in aqueous environmental samples, using pneumatically assisted electrospray (ESI) liquid chromatography-mass spectrometry (LC-MS) is presented. Arylphenoxypropionic acids are a new class of herbicides used for the selective removal of most grass species from any nongrass crop. These herbicides are commercialized as herbicide esters. It has been shown that the ester derivatives undergo fast hydrolysis in the presence of vegetable tissues and soil bacteria, yielding the corresponding free acid. The analytical procedure involves passing 1l of surface or ground water and 2l of drinking-water samples, through a 0.5-g graphitized carbon black (GCB) extraction cartridge. A conventional 4.6-mm I.D. reversed-phase LC C18, operating with a 1 ml/min mobile phase flow-rate, was used for chromatographing the analytes. A flow of 200 microliters/min of the column effluent was diverted to the ESI source. The ESI source was operated in positive-ion mode for neutral pesticides and in negative-ion mode for acid pesticides. For ion-signal optimization, the effect of the concentration of the acid in the mobile phase on the response of the ESI-MS detector was investigated. By evaluating the specificity and sensitivity of the method, the effects of varying the orifice plate voltage on the production of the diagnostic fragment and the response of the MS detector were also investigated. For the analyte considered, the response of the mass detector was linearly related to the amount of the analyte injected between 1 and 200 ng. In all cases, recoveries of the analytes were better than 91%. The limit of detection (signal-to-noise ratio = 3) of the method for the pesticides considered in drinking water samples was estimated to be about 3-10 ng/l.

Chromatography, High Pressure Liquid↗
PubMed1998

Development of a method based on liquid chromatography-electrospray mass spectrometry for analyzing imidazolinone herbicides in environmental water at part-per-trillion levels.

An evaluation was made of the feasibility of using reversed-phase liquid chromatography-mass spectrometry with an electrospray interface (LC-ESI-MS) to measure traces of imidazolinone herbicides in different natural water samples. The imidazolinones are a significant new class of low-use-rate, reduced-environmental-risk herbicides for the protection of a wide variety of agricultural commodities. The procedure used involved passing 0.5, 1, 2 1 of river, ground and drinking water samples, respectively, through a 0.5 g graphitized carbon black (GCB) extraction cartridge. Analytes were eluted from the GCB surface by 8 ml of a methylene chloride-methanol (80:20, v/v) solution acidified with formic acid, 25 mM. Recovery was higher than 89% irrespective of the aqueous matrix in which the analytes were dissolved. A conventional 4.6 mm I.D. reversed-phase LC C18 column operating with a mobile phase flow-rate of 1 ml/min was used to chromatograph the analytes. A flow of 50 microliters/min of the column effluent was diverted to the ESI source. The effects of acid concentration on ESI-MS detector response in the mobile phase were investigated. The effects on the production of diagnostic fragments produced by varying the orifice plate voltage and the response of the MS detector were also evaluated. For the analyte considered, the response of the mass detector was linearly related to the amount of analyte injected between 1 and 50 ng. The limit of detection (signal-to-noise ratio = 3) of the method for the pesticides considered in drinking water samples was estimated to be about 2-5 ng/l.

Chromatography, Liquid↗
PubMed1997

Extracorporeal photochemotherapy induces apoptosis of infiltrating lymphoid cells in patients with mycosis fungoides in early stages. A quantitative histological study.

Extracorporeal photochemotherapy (ExP) is a well-tolerated new form of chemoimmunotherapy, which is considered to be effective for cutaneous T-cell lymphoma (CTCL) and the treatment of choice for Sézary syndrome. Improvements have also been seen in patients with non-erythrodermic mycosis fungoides (MF) in the early stages, even when tumour cells are not detectable in the peripheral blood. In this study, we used ExP as a monotherapy in seven patients who had early stage (Ib) MF, and who were no longer responsive to or had contraindications for other therapies. We observed a clinical improvement in the disease after 12 months of treatment: one patient showed a complete response, five a partial response, and one remained stable. In each patient we compared skin biopsies of large plaque lesions before and after the treatment. We undertook a histological evaluation of the infiltrate. The lymphoid cell proliferation and death rates were quantified using the following parameters; lymphoid cell density (LCD), Ki67 + lymphoid cell nuclei percentage (Ki67 + Lcn percentage), and apoptotic index (AI). Significant decreases in the lymphoid cell infiltrate and in cell proliferation, and a significant increase in AI were observed after therapy. The mean LCD decreased from 187 +/- 33 to 34 +/- 17.7, Ki67 + Lcn mean percentage decreased from 16.9 +/- 3.9 to 4.9 +/- 2.4, and the AI mean value increased from 0.05 +/- 0.03 to 2.41 +/- 1.54. Our results suggest a role for apoptosis in the improvement of the skin lesions and are in line with some reports on the mode of action of ExP. Although the way in which ExP works needs to be clarified further, it does seem to stimulate a CD8+ cell-mediated anticlonotypic activity against circulating pathogenic clones. Furthermore, a release of tumour necrosis factor alpha (TNF-alpha) by circulating monocytes has been demonstrated after ExP. Both are known to induce cell death by apoptosis.

Aged↗
PubMed1988

High-performance liquid chromatographic analysis of norfloxacin in human tissues and plasma with fluorescence detection.

A high-performance liquid chromatographic analysis with fluorimetric detection is described for the quantitative determination of norfloxacin in renal, prostatic tissues and in plasma. The analytical procedure in the tissue pretreatment, consists of purification of the obtained sample by a solid state extraction and quantitation by HPLC. The samples were chromatographed on a C(8) reversed-phase column. Analytical recoveries ranged from 95.2 to 97.6%. Within and between day precision were assessed by analysing serum containing 50 and 500 ng/ml norfloxacin. At each concentration, within day precision was < or = 3.6% (relative standard deviation, n = 10) and day-to-day precision was < or = 5.3% (n = 10). Limit of detection was ca 1 ng/ml.

Journal Article↗
PubMed1987

High-performance liquid chromatographic determination of norfloxacin in human tissues and plasma with fluorescence detection.

A high-performance liquid chromatographic method with fluorimetric detection is described for the quantitative determination of norfloxacin in renal and prostatic tissues and in plasma. It consists of tissue pretreatment, purification by solid-state extraction and separation and quantification by high-performance liquid chromatography on a C8 reversed-phase column. Analytical recoveries ranged from 95.2 to 97.6%. Within-day and between-day precision were assessed by analysing serum containing 50 and 500 ng/ml norfloxacin. At each concentration, the within-day precision was less than or equal to 3.6% (coefficient of variation; n = 10) and the day-to-day precision was less than or equal to 5.3% (n = 10). The limit of detection was 1 ng/ml.

Chromatography, High Pressure Liquid↗
PubMed1986

Liquid-chromatographic determination of progesterone in serum, with spectrophotometric detection.

In this precise, accurate, and specific liquid-chromatographic procedure for determining progesterone in serum, the serum is diluted 10-fold with water/methanol (65/35 by vol), and the progesterone is extracted from the sample by passage through a column of graphitized carbon black (Carbopack B, Supelco). After washing the column, we elute the progesterone with chloroform/methanol (90/10 by vol), which is then evaporated. The progesterone is separated on a reversed-phase C18 column with a mobile phase of acetonitrile/water, (46/54 by vol) at a flow rate of 1.6 mL/min. The eluted compound is detected by absorbance at 242 nm. Analytical recoveries for progesterone varied from 96.0 to 97.8%. Within-day and day-to-day precision, determined by analyzing pooled serum, ranged from 3.4 to 6.4%, and 4.1 to 7.9%, respectively. The limit of detection was about 0.2 micrograms/L. Numerous drugs and steroids tested did not interfere. Results correlated (r = 0.997) well with those by radioimmunoassay.

Blood Proteins↗
PubMed1984

Total phosphorus determination in human bile. Comparison between two spectrometric methods.

The two most commonly used spectrometric methods for the determination of the phosphorus content of human bile are compared. The optimum experimental conditions are studied, and the analytical characteristics of the two methods, using both standard samples and human bile, are evaluated. The methods are compared on the basis of their sensitivity, precision and accuracy, and the correlation between the two techniques demonstrated using fifteen samples of human bile. Data obtained by both methods have been used to calculate lithogenic index values.

Journal Article↗
PubMed1982

Simple, reliable chromatographic measurement of oxalate in urine.

In this assay for oxalate in urine, oxalate is adsorbed from the urine onto graphitized carbon black (Carbopack B). After desorption and removal of the solvent, oxalic acid is gas-chromatographically measured after being derivatized with BF3/methanol. Chromatography is on Carbopack B/polyethylene glycol (Mr 20000), 93.7/6.3 by weight. The lower limit of detection of urinary oxalate is about 3 mg/L (CV less than or equal to 3.6%). A series of oxalate determinations in 24-h urine samples of 15 subjects gave a mean of 47.1 (SD 15.4) mg/24 h, with an analytical recovery of 97.4% (SD 3.0%, range 93.6-102.4%). Total analysis time for one sample is about 2 h.

Chromatography, Gas↗