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S Pellegrino

Publications and source records attributed to S Pellegrino.

At least 19 recordsLinked to original sources
PubMed2006

Isothiazoles. Part XV. A mild and efficient synthesis of new antiproliferative 5-sulfanylsubstituted 3-alkylaminoisothiazole 1,1-dioxides.

5-Sulfanyl-3-alkylaminoisothiazole dioxide derivatives have been identified as a new class of potent inhibitors of rat aortic myocite proliferation. They were prepared by applying a simple methodology able to introduce a heteroatom on C-5 of the 3-alkylaminoisothiazole dioxide system. 3-Aminosubstituted-5-chloroisothiazole dioxides react smoothly not only with S-nucleophiles but also with N- and O-nucleophiles affording the corresponding 5-heterosubstituted isothiazole dioxides through an addition-elimination reaction. The behavior of 3-alkylamino-4-bromo-isothiazole 1,1-dioxide with S-, N- and O-nucleophiles affording the same products has also been described. On the contrary, the 3-amino-4,5-unsubstituted isothiazole dioxide system reacts easily only with sulfur nucleophiles affording the corresponding 4,5-dihydro-5-sulfanylderivatives through a simple Michael addition reaction.

Alkyl and Aryl Transferases↗
PubMed2003

[Primary leiomyoma of the lung, with clear-cell features and admixed alveolar spaces: description of a case presenting with pneumothorax].

OBJECTIVE: To report about a primary leiomyoma of the lung, with clear cell features and with admixed alveolar epithelium. RESULTS AND CONCLUSIONS: The patient, a 18-year-old female, non smoker, presented with a well-delimited pleuro-pulmonary mass, 6,5 cm across, located in the right upper lobe. The mass was discovered 5 years previously, following an episode of spontaneous pneumothorax; initially interpreted as an intralobar pulmonary sequestration, it was subsequently removed due to a small dimensional increase. A gynaecological examination, a thoracic CT-scan obtained 2 years after operation, and a recent abdomino-pelvic echography were negative. The patient is alive and well 7 years after surgery. Microscopically, the lesion was well delimited and it was punctuated by multiple cysts of variable dimensions, covered by bland cubic cells. The solid part of the lesion was composed by oval, clear cells, merging with fusiform elements with densely eosinophilic cytoplasm. Significant atypia, mitoses and necrosis were absent. Immunohistochemically, both oval and spindle cells were strongly positive for vimentin, smooth muscle actin, desmin and h-caldesmon, negative for cytokeratin, EMA, CD-34, CD-10, CD-117, HMB-45, TTF-1, BCL-2, GFAP, calretinin, chromogranin, estrogen and progesterone receptors. Cells covering the cystic spaces were positive for cytokeratin, TTF-1 and EMA, negative for all the other antibodies tested. Smooth muscle proliferations of the lung are briefly discussed, together with the most important problems in differential diagnosis.

Adolescent↗
PubMed2003

[Solitary fibrous pseudopapillary tumor of the lung: pulmonary fibroadenoma and adenofibroma revisited].

We describe a peculiar pulmonary lesion, that we interpreted as a pseudopapillary variant of solitary fibrous tumor. The patient was a 62-year-old asymptomatic male, non smoking, presenting with a peripheral nodule, 0.8 cm across, located in the lower lobe of the right lung. The patient is alive and well 18 months after surgical excision of the nodule. Microscopically, the lesion was well-circumscribed and characterized by a diffuse pseudopapillary pattern. Pseudopapillae were large, and were covered by a rim of cubic epithelium devoid of atypia. The stromal axis was fibrous and contained scattered bland spindle cells. Immunohistochemically, the latter were strongly positive for vimentin and CD34, focally positive for BCL2 and CD99, negative for cytokeratin, EMA, TTF1, calretinin, smooth muscle actin, desmin and S100 protein; the epithelial cells were immunoreactive for cytokeratin, EMA and TTF1. We interpret this lesion as a peculiar pseudopapillary variant of solitary fibrous tumor, corresponding to what has been reported in the literature as pulmonary adenofibroma and fibroadenoma. The most important differential diagnostic considerations are briefly discussed.

Adenofibroma↗
PubMed2002

Alcohol abstinence does not offset the strong negative effect of lifetime alcohol consumption on the outcome of interferon therapy.

Heavy alcohol consumption has been reported to negatively affect the outcome of interferon therapy. We studied the impact of lifetime alcohol consumption in patients with chronic hepatitis C treated with interferon after 6 months of alcohol withdrawal. Alcohol intake was measured when patients with chronic hepatitis C were referred to us for the first time, and from that moment complete abstinence was recommended. After 6 months of abstinence, 150 patients with persistent elevated serum alanine aminotransferase (ALT) have been treated with interferon (IFN)-alpha, 3 or 6 microU three times per week for 12 months. Univariate and multivariate analysis were performed to identify the predictors of treatment response. Carbohydrate-deficient transferrin was employed to assess alcoholic abstinence. The sustained response rate felt from 33% in nondrinkers to 20% of mild-drinkers and to only 9% in heavy drinkers. Drinker patients showed a relapse rate twice as high as that of nondrinkers. According to the multivariate analysis, the strongest independent predictors of nonresponse were genotype 1b infection, age of the patients and their lifetime alcohol intake. Carbohydrate-deficient transferrin detected at baseline, at 3 months of therapy and at the end of follow-up gave a positive result only in eight determinations (1.77%), confirming the compliance of patients to our recommendation of alcohol abstinence. Lifetime alcohol consumption has a strong negative effect on the outcome of interferon treatment, mainly in heavy drinkers. A 6-month period of abstinence may not be sufficient to offset this negative effect on treatment outcome.

Adult↗
PubMed2001

Biliary lipid composition in cholesterol microlithiasis.

BACKGROUND: Little information is available on the pathogenesis of cholesterol microlithiasis, and it is not clear if biliary lipid composition in these patients is similar to changes seen in cholesterol gall stone patients. AIMS: To measure biliary lipid composition in patients with cholesterol microlithiasis. PATIENTS: Eleven patients with cholesterol microlithiasis, 20 cholesterol gall stone patients, and 17 healthy controls. METHODS: Duodenal bile was collected in the fasting state during ceruletide infusion. Biliary cholesterol, phospholipids, and total bile acids were analysed by enzymatic assays, and conjugated bile acids by high pressure liquid chromatography. RESULTS: Patients with microlithiasis had a cholesterol saturation index significantly higher than controls (mean value 1.30 (95% confidence interval 1.05-1.54) v 0.90 (0.72-1.08)) but similar to gall stone patients (1.51 (1.40-1.63)). This was due to a significant decrease in per cent phospholipid (10.0% (7.1-12.8)) compared with controls (21.4% (18.1-24.6)) and gall stone patients (24.9% (20.5-29.3)). Per cent cholesterol was similar in patients with microlithiasis and controls (5.3% (4.5-6.1) and 5.6 % (4.3-6.8), respectively) but was significantly increased in gall stone patients (10.9% (9.3-12.4)). Bile acid composition in patients with microlithiasis was similar to controls whereas in gall stone patients deoxycholic acid was significantly increased: 27.3% (24.8-29.7) v 19.0% (15.7-22.2) in controls and 20.6% (14.9-26.2) in patients with microlithiasis. CONCLUSION: Patients with cholesterol microlithiasis have biliary cholesterol supersaturation, similarly to cholesterol gall stone patients. Whereas in the latter this is due to increased per cent cholesterol, in patients with microlithiasis this is caused by phospholipid deficiency, with normal per cent cholesterol and normal biliary bile acid composition.

Adult↗
PubMed1999

Liquid chromatographic determination of ethyl alcohol in body fluids.

A high-performance liquid chromatographic technique for ethyl alcohol determination in body fluids is proposed. Ethyl alcohol is quantitatively converted into acetaldehyde-phenylhydrazone by oxidation in the presence of alcohol dehydrogenase, nicotinamide-adenine dinucleotide and phenylhydrazine. The derivative is suitable for reversed-phase liquid chromatography and ultraviolet detection at 276 nm. The limits of linearity, detection and quantification as well as accuracy and reproducibility were investigated in water, serum and whole blood. Analytical responses were linear within the 0.008 to 5 g/l range, and the limit of quantification was 0.02 g/l both in aqueous standard and in biological matrix assays. Mean analytical recovery of ethyl alcohol in blood serum averaged 98.2+/-4.2%, imprecision (CV%) at 0.80 g/l was 2.2%, and the limit of quantification was 0.02 g/l. Serum concentrations of persons that avoided alcoholic beverages for a week were less than the limit of quantification. Ethyl alcohol concentrations in serum and whole blood compared well with those obtained by headspace gas chromatography. This simple and reliable procedure, which was also used for a urine assay, could be suitable for validation of the screening procedures used to monitor ethanol abuse.

Chromatography, High Pressure Liquid↗
PubMed1999

Biliary bile acid composition in gastric cancer.

Bile reflux into the stomach has been considered carcinogenic. Secondary bile acids, and in particular deoxycholic acid, have been shown to act experimentally as co-carcinogens in the colon and are increased in patients with colorectal adenocarcinoma. No information is available with respect to biliary bile acid composition in patients with gastric cancer. We studied biliary bile acid composition in 11 patients with gastric cancer and 23 healthy controls. Bile acids were measured using high-performance liquid chromatography. The site of gastric cancer was the antrum in 6 patients and body in 5. There were 6 intestinal-type and 5 diffuse adenocarcinomas. Only 2 patients had Helicobacter pylori infection. Deoxycholic acid constituted 24% +/- 2% of biliary bile acid in gastric cancer patients versus 22% +/- 2% in healthy controls (NS). Similarly, no differences were found between the two groups for all other bile acids. Deoxycholic acid constituted 23% +/- 3% of biliary bile acid (NS vs. controls) in patients with antral adenocarcinoma and 25% +/- 2% (NS vs. controls) in patients with intestinal-type gastric adenocarcinoma. Gastric adenocarcinoma is not associated with an increase in the more-toxic secondary bile acids, and deoxycholic acid in particular. This reduces the importance of bile acid composition as a promotor in gastric carcinogenesis.

Adenocarcinoma↗
PubMed1998

Biliary lipid composition in idiopathic bile acid malabsorption.

BACKGROUND: Chronic diarrhoea is the clinical hallmark of patients presenting with idiopathic bile acid malabsorption. Its pathogenesis is unknown; colonic water secretion can be induced by dihydroxy bile acids, but it is not known whether enrichment of the bile acid pool with these bile acids occurs in such patients. Furthermore, bile acid malabsorption is known to affect biliary lipid composition, but no information is available for the idiopathic type. AIMS: To verify: (a) whether diarrhoea in patients with idiopathic bile acid malabsorption is associated with enrichment of the bile acid pool with dihydroxy bile acids; and (b) whether supersaturation with cholesterol of duodenal bile occurs in such patients as a result of chronic bile acid depletion. PATIENTS: Thirteen patients with idiopathic bile acid malabsorption diagnosed according to abnormal 75SeHCAT test and absence of other organic diseases, and 23 control subjects. METHODS: Bile rich duodenal fluid was collected during intravenous ceruletide infusion in the fasting state. Biliary lipids were analysed by enzymatic assays and bile acids by high performance liquid chromatography. RESULTS: Patients with idiopathic bile acid malabsorption had a cholesterol saturation index similar to controls. Bile acid composition showed only a decrease in percentage cholic acid (29 (2)% versus 36 (2)%; p<0.05); the dihydroxy:trihydroxy bile acid ratio was similar to controls. CONCLUSIONS: Patients with idiopathic bile acid malabsorption do not have an increased risk of forming cholesterol gallstones. The mechanism of diarrhoea does not seem to depend on an enrichment of the bile acid pool with dihydroxy bile acids.

Adult↗
PubMed1997

The coiled-coil region of the G protein beta subunit. Mutational analysis of Ggamma and effector interactions.

The beta and gamma subunits of the heterotrimeric G proteins remain tightly associated throughout the signaling cycle as the betagamma dimer interacts with Galpha, receptors, and effectors. A coiled-coil structure involving alpha-helical segments at the N termini of the beta and gamma subunits contributes to the dimerization interface and has been implicated in effector signaling in yeast. Scanning mutagenesis of the coiled-coil region of the mammalian beta1 subunit was performed to examine the effect of point mutations on betagamma assembly and effector signaling in COS cell cotransfection assays. In addition to the E10K mutation described previously, mutations A11E, L14E, and I18E in beta1 were found to block betagamma association, as evidenced by the failure of the Gbeta mutants to undergo cytosolic translocation with cotransfected nonisoprenylated Ggamma. Although none of 14 beta1 point mutations prevented the betagamma-dependent activation of the c-Jun N-terminal kinase (JNK) effector pathway, the D20K point mutation enhanced JNK but not phospholipase C-beta2 activation. These findings implicate the coiled-coil region of Gbeta in JNK signaling, provide further evidence that the structural features of the betagamma complex mediating effector regulation may differ among effectors, and identify single codons in the mammalian beta subunit where mutation might yield a phenotype of defective signal transduction.

Amino Acid Sequence↗
PubMed1993

High-performance liquid chromatographic microassay for L-glutamate:glyoxylate aminotransferase activity in human liver. Application in primary hyperoxaluria type 1.

A rapid and sensitive liquid chromatographic technique to determine L-glutamate:glyoxylate and aminotransferase (EC 2.6.1.4) activity in human liver is described. Homogenised tissue was incubated for 60 min in the presence of substrates and the 2-oxoglutarate generated was converted into the corresponding phenylhydrazone which was determined using reversed-phase high-performance liquid chromatography. The procedure allowed the detection of the enzyme activity expressed by 7.5 micrograms of liver protein, it was more sensitive and less time-consuming than the spectrophotometric procedure previously used. No significant differences were found between normal controls and patients with primary hyperoxaluria. In an 8-month-infant with primary hyperoxaluria type 1, the enzyme activity was reduced to 16% of the average control values.

Chromatography, High Pressure Liquid↗
PubMed1992

High-performance liquid chromatographic microassay for methyl ethyl ketone in urine as the 2,4-dinitrophenyl-hydrazone derivative.

We report a high-performance liquid chromatographic procedure for determining methyl ethyl ketone in urine. The method is based on pre-column derivatization with 2,4-dinitrophenylhydrazine and liquid-liquid extraction of the derivative. The analyte is chromatographically separated from other urine constituents in less than 12 min and is detected by UV absorption at 360 nm. Peak height and concentration are linearly related. The relative standard deviation assessed for within-day imprecision was 3.2% at the 2.21 mg/l level. The mean analytical recovery from urines spiked with 1.0 mg/l ketone was 96.0 +/- 6.1%. The simple sample handling, the small volume of urine required and the short amount of time taken for the whole procedure make it suitable for routine biomonitoring of exposure to methyl ethyl ketone in industrial workers. The concentration in urine from nine non-exposed controls was less than 0.1 mg/l. The concentrations measured in urine samples from 60 exposed workers ranged from 0.1 to 1.1 mg/l and from 0.3 to 3.6 mg/l at the before- and the end-shift collections, respectively.

Butanones↗
PubMed1992

High-performance liquid chromatographic microassay for L-alanine:glyoxylate aminotransferase activity in human liver.

We examine the suitability of a rapid and sensitive liquid chromatographic technique to determine L-alanine:glyoxylate aminotransferase (AGT) activity in human liver. Homogenised tissue was incubated for 30 min in the presence of substrates and the generated pyruvate was converted into the corresponding phenylhydrazone which was determined using reversed-phase high-performance liquid chromatography (HPLC). The procedure allowed the detection of the enzyme activity expressed by 10 micrograms of liver protein and was rapid enough resulting more sensitive and less time-consuming than the previous colorimetric one. We found that AGT activity in two hyperoxaluria type 1 patients was reduced as compared with controls. Also, cirrhotic patients had very low enzyme activities, even in the absence of detectable disorders of oxalate metabolism and this was ascribed to abnormal liver morphology. This may represent a misleading drawback if diagnosis of type 1 primary hyperoxaluria (PH1) uniquely relies on AGT assay.

Alanine↗
PubMed1992

Rapid high-performance liquid chromatographic determination of urinary N-(1-methylethyl)-N'-phenyl-1,4-benzenediamine in workers exposed to aromatic amines.

A procedure has been developed for determining N-(1-methylethyl)-N'-phenyl-1,4-benzenediamine in urine by using high-performance liquid chromatography. The method uses chloroform extraction for partial clean-up of the urine sample. The separation is carried out on a reversed-phase column using 65 mmol/l aqueous ammonium acetate in acetonitrile (30:70, v/v) as the mobile phase. The column effluent is monitored at 290 nm with an ultraviolet detector. The analyte is separated from other normal urine constituents in less than 4 min. Peak height and concentration are linearly related. Coefficients of variation assessed for within-day reproducibility were 5.9 and 3.7% at concentrations of 22.3 and 92.1 micrograms/l, respectively. The mean analytical recovery from urine samples spiked with known amounts of amine was 89.7 +/- 6.8%. The request of only a small volume of urine and the simple pre-treatment procedure makes it suitable for the routine monitoring of the exposure of rubber vulcanization workers to aromatic amines.

Amines↗
PubMed1991

Nasal provocation test with lysine acetylsalicylate in aspirin-sensitive patients.

The authors have studied nasal provocation testing (NPT) with aspirin in 45 aspirin-sensitive patients (40 affected by nasal polyposis) and in 38 aspirin-tolerant patients (27 affected by nasal polyposis). The test was positive in 37.7% of aspirin-intolerant subjects, but only in 7.9% of subjects in the control group (P less than .01).

Adult↗
PubMed1990

Ion chromatographic determination of plasma oxalate in healthy subjects, in patients with chronic renal failure and in cases of hyperoxaluric syndromes.

An ion chromatographic procedure for the determination of plasma oxalate is proposed, in which the ultrafiltered sample is injected into an ion-chromatographic system. Sample processing appears effective in avoiding spontaneous oxalogenesis. Sensitivity (down to 1.0 mumol/l) allows determinations in normal and pathological samples; recoveries from plasma ultrafiltration are 94.6 +/- 11.7%. Protein binding was investigated and precautions to improve recoveries from plasma ultrafiltration are proposed. The technique is simple to perform from healthy controls averaged 6.75 +/- 2.62 mumols/l (mean +/- S.D. n = 18); samples from patients with primary hyperoxaluria and chronic renal failure undergoing regular dialysis were also analysed and some of the data obtained are reported and discussed.

Adult↗
PubMed1989

Derivatization and high-performance liquid chromatographic determination of urinary glycolic acid.

A high-performance liquid chromatographic method for the determination of urinary glycolic acid is proposed, based on pre-column derivatization with phenylhydrazine coupled with the enzymatic oxidation of glycolate to glyoxylate. The phenylhydrazone formed is separated by liquid chromatography and detected at 324 nm. The minimum detectable concentration of glycolate was 10.0 mumol/l. The recovery of glycolate added to urine averaged 96.1%. The day-to-day coefficients of variation calculated by analysis of two urine samples with normal and high glycolate contents were 4.6 and 7.5%, respectively. Results of analyses of urine samples from healthy persons, idiopathic calcium stone formers and Type I primary hyperoxaluria patients are reported.

Chromatography, High Pressure Liquid↗
PubMed1989

Pancuronium allergy: a case report.

A case of anaphylactic shock to pancuronium bromide is described in which a type I immunological reaction occurred. A 33-yr-old male anaesthetist, with no family or personal history of allergy, collapsed soon after induction of anaesthesia. The drugs used included fentanyl, droperidol, thiopentone and pancuronium. Diffuse erythema occurred, with probable cardiac arrest. The patient was treated with cardiac massage, sympathomimetics and cortisone, and made a complete recovery. Examination (skin tests, passive transfer according to Prausnitz and Küstner, in vitro lymphocyte transformation test, total IgE assay) revealed that the allergic reaction was to pancuronium bromide.

Adult↗