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A Bortoli

Publications and source records attributed to A Bortoli.

34 records · Page 2Linked to original sources
PubMed1998

[Environmental lead exposure in the Venetian population from 1976-1992].

Blood lead levels observed in the general population of Venice and the surrounding area are reported for the period between 1976 and 1992. A time dependent decrease of blood lead levels is evident and parallels the step wise decrease of lead levels in gasoline which took place between 1981 and 1991. The observed lowering time trend of blood lead levels could possibly be ascribed, perhaps not negligibly, to technological improvements, the development of new analytical procedures and the continuous practice of quality control.

Adolescent↗
PubMed1997

Reference values of urinary chromium in Italy.

OBJECTIVES: The paper describes the results of a polycentric study for the assessment of reference values of urinary chromium (U-Cr) in the Italian population. METHOD: A total of 890 subjects (58.3% males and 41.7% females) were selected on the basis of standardized criteria in eight different areas of Italy. Urinary chromium was determined on morning spot samples collected using standardized procedures. The U-Cr was determined independently by three laboratories using an Electrothermic atomization-Atomic Absorption Spectrometry (ETA-AAS) method with a detection limit of 0.05 microgram/l, adopting-for the statistical analysis-the median value of the results of the three laboratories. The between-laboratories within-subjects standard deviation was 0.049 microgram/l. Due to the high proportion (approx, 28%) of undetectable chromium levels, the geometric mean (GM) and geometric standard deviation (GSD) were estimated using a procedure of linear interpolation. The analysis of the effects of some variables (sex, age, center, residence, smoking and drinking habits) on the U-Cr values, was also performed, by multiple regression analysis after logarithmic transformation, using GM and SD. RESULTS: The reference value of U-Cr was of 0.08 microgram/l as an estimated GM, whereas the expected distribution ranged from not detectable (nd) (95% CI = nd-0.06) to 0.24 microgram/l (95th percentile; 95% CI = 0.20-0.31). Among the variables studied, only geographical area and sex significantly influenced the U-Cr levels. In subjects selected in the provinces of Bari and Venice values of U-Cr were significantly lower than those determined in subjects residing in other areas. CONCLUSIONS: From our investigation the reference values for U-Cr were lower than those obtained in previous investigations. In addition it confirms a further reduction in U-Cr levels following the previous decline reported in the 1970s and 1980s. In over 20 years U-Cr values in the general population dropped from values greater than 1 microgram/l to values between 0.5 and 0.2 microgram/l. The reasons of this progressive decline cannot be attributed in our opinion to a reduced intake of the metal, but mainly to the improvement in analytical instrumentation and methods. A further decrease may be ascribed to a more accurate definition of the reference groups and to a better control of pre-analytical factors. Considering that the reference values for U-Cr are much lower than those determined some decades ago, toxicological studies in order to verify the significance of biological limit values currently suggested for chromium seem to be necessary.

Adult↗
PubMed1997

Randomized study comparing omeprazole plus amoxycillin versus omeprazole plus clarithromycin for eradication of Helicobacter pylori.

BACKGROUND: Dual therapy with omeprazole plus amoxycillin or with omeprazole plus clarithromycin has been proposed for eradication of Helicobacter pylori. The main problem is the great variability in the rate of eradication. METHODS: A group of 287 consecutive patients with active peptic ulcers and H. pylori infections were admitted to a prospective, randomized, multicentre study, to be given omeprazole 20 mg b.d. plus either amoxycillin 1 g b.d. or clarithromycin 500 mg t.d.s. for 2 weeks. Cure was defined as the absence of H. pylori infection, 4-6 weeks after completing anti-microbial therapy, assessed by urease activity and histology of antral and body gastric biopsies. RESULTS: The bacteria were eradicated in 68/143 patients (48%) treated with amoxycillin and omeprazole and 70/144 patients (49%) treated with clarithromycin and omeprazole (intention-to-treat analysis). The ulcers were healed in 118/127 patients (93%) treated with amoxycillin and in 115/123 (94%) of those treated with clarithromycin. Undesirable effects were rare with both treatments. CONCLUSIONS: Combined treatment with omeprazole plus either amoxycillin or clarithromycin produced a high percentage of short-term healing of ulcers and was well tolerated, but is not useful as first-line anti-Helicobacter pylori treatment.

Adolescent↗
PubMed1997

Portal hypertensive gastropathy: reproducibility of a classification, prevalence of elementary lesions, sensitivity and specificity in the diagnosis of cirrhosis of the liver. A NIEC multicentre study. New Italian Endoscopic Club.

OBJECTIVE: To classify elementary endoscopic lesions of portal hypertensive gastropathy, assess their reproducibility, prevalences, sensitivity and specificity in the diagnosis of cirrhosis of the liver. METHODS: 1) A classification of portal hypertensive gastropathy elementary lesions was defined. 2) Thirty-two endoscopists evaluated videotapes of endoscopic examinations of patients with liver cirrhosis to assess beyond-chance agreement (kappa). 3) Fifteen centres enrolled consecutive patients with or without cirrhosis of the liver and recorded portal hypertensive gastropathy pattern according to its location. RESULTS: 1) Four elementary lesions (Mosaic-Like Pattern, Red Point Lesions, Cherry Red Spots, Black-Brown Spots) were identified, and graded. 2) A fair to good beyond-chance agreement was obtained for all 4 lesions. 3) portal hypertensive gastropathy prevalence was higher in patients with cirrhosis of the liver (0.63, sensitivity) than in controls (0.17). Mosaic-like pattern was the most prevalent sign (0.54). Specificity of portal hypertensive gastropathy was 0.83. Portal hypertensive gastropathy was tentatively classified as mild or severe when mosaic-like pattern alone or red marks of any kind were present, respectively; this classification led to a further improvement in reproducibility. CONCLUSIONS: Our results suggest that a sufficient degree of agreement can be achieved in recording portal hypertensive gastropathy. Therefore, the New Italian Endoscopic Club classification should be used to evaluate the natural history of this condition.

Diagnosis, Differential↗
PubMed1996

Determination of Cd, Co, Cu, Mn, Ni, Pb, and Zn by Inductively Coupled Plasma Mass Spectroscopy or Flame Atomic Absorption Spectrometry after On-line Preconcentration and Solvent Extraction by Flow Injection System

The concentrations of Cd, Co, Cu, Mn, Ni, Pb, and Zn in natural and sea waters are too low to be directly determined with by flame atomic absorption spectrometry (FAAS) or graphite furnace atomic absorption spectrometry (GFAAS). Specific sample preparations are requested that make possible the determination of these analytes by preconcentration or extraction. These techniques are affected by severe problems of sample contamination. In this work Cd, Co, Cu, Mn, Ni, Pb, and Zn were determined by inductively coupled plasma mass spectroscopy (ICP-MS) or by atomic absorption spectrometry, in fresh and seawater samples, after on-line preconcentration and following solvent elution with a flow injection system. Bonded silica with octadecyl functional group C18, packed in a microcolumn of 100-μl capacity, was used to collect diethyldithiocarbamate complexes of the heavy metals in aqueous solutions. The metals are complexed with a chelating agent, adsorbed on the C18 column, and eluted with methanol directly in the flow injection system. The methanolic stream can be addressed to FAAS for direct determination of Cu, Ni, and Zn, or collected in a vial for successive analysis by GFAAS. The eluted samples can be also dried in a vacuum container and restored to a little volume with concentrated HNO3 and Milli-Q water for analysis by ICP-MS or GFAAS.

Journal Article↗
PubMed1995

[Instrumental analysis of trace elements].

The study of trace elements in human medicine and toxicology requires very low concentration of these elements to be determined in biological matrices. Among the analytical methodologies of major impact there are isotopic dilution mass spectrometry, neutron activation analysis, anodic stripping voltammetry, inductively coupled plasma atomic emission spectrometry and electrothermal atomization atomic emission spectrometry. This last, in particular, provides high sensitivity and reliability for the determination of numerous elements. Instrumental and methodological improvements leading to these achievements include the adoption of the so-called stabilized temperature platform furnace, the introduction of universal matrix modifiers, oxygen charring steps and background correction systems based on the Zeeman effect.

Body Fluids↗
PubMed1995

First bleeding episode from oesophageal varices in cirrhotic patients: a prospective study of endoscopic predictive factors.

Two hundred patients affected by liver cirrhosis and oesophageal varices were studied in 9 Gastrointestinal Units in Lombardy (Northern Italy) in order to assess factors possibly related to variceal bleeding. Only patients without any previous episode of gastrointestinal bleeding were included in the prospective evaluation. For each patient demographic data, aetiology of cirrhosis, various clinical and biochemical parameters able to group patients into the three Child-Pugh Classes, endoscopic items for calculation of Beppu's and of NIEC prognostic scores were recorded on computerized cards. Patients were regularly interviewed every three months for one year and underwent an upper gastrointestinal endoscopy at enrollment, after six months and in case of bleeding. Within the twelve-month follow-up period, 29 out of the 200 patients (14%) bled and 52 out of 200 died (26%). In 16 of the 52 patients who died (59% of bleeding patients) death was directly related to gastrointestinal bleeding. Bleeding from oesophageal varices was endoscopically proven in 19/29 patients, in another 9 bleeding was classified as from unknown source and in one patient a bleeding gastric ulcer was diagnosed. Univariate analysis of all the recorded clinical, biochemical and endoscopic parameters, performed by Chi-square method and Fisher exact test showed that the presence of RWM (p < 0.001) was the only factor significantly associated to variceal bleeding within one year. Relationship between size of varices and bleeding was very close to the statistical significance but did not achieve it (p = 0.058).

Adult↗
PubMed1995

Analytical problems in mercury analysis of seafood.

It is generally accepted that seafood represents one of the major sources of mercury to man. In this work two interlaboratory proficiency tests are described for the analysis of mercury in seafood. Thirty-seven public control and food industries laboratories participated in the first test, while 29 participants were included in the second one. Moreover, in order to clarify whether sampling of different edible muscle tissues of the same fish could affect the analytical results, the top, the central and the bottom portion of 28 fishes were examined. The different portions of fish showed no significant difference in mercury concentrations. Two different wet digestion methods (microwave oven and reflux in quartz vessels) were also tested in the case of 11 fishes. A systematic difference was observed between the two sets of results obtained with these digestion methods.

Animals↗
PubMed1991

Selenium status and effect of selenium supplementation in a group of elderly women.

Plasma selenium was determined in 92 elderly women: a marked decrease was observed from the age of 65 years. Se-status in 20 elderly women was explored by investigation of the effects of 30 days' Se-supplementation with enriched tablets (Selevit-E) 66 micrograms per day. Serial determination was performed for Se plasma, e-GSH-Px (glutathione peroxidase), MDA (malondialdehyde) and Vitamin E. Significant changes were observed in Se, e-GSH-Px and MDA.

Aged↗
PubMed1989

The number and distribution of esterase 6 alleles in populations of Drosophila melanogaster.

High resolution electrophoretic analyses of the polymorphic esterase 6 enzyme have been carried out on 133 isoallelic lines from three Australian populations of Drosophila melanogaster spanning 25 degrees of latitude. These and previous data for 157 lines from another Australian population at an intermediate latitude reveal a total of 14 polymorphic esterase 6 allozymes, falling into five major mobility classes. Two classes, EST6-F and EST6-S, contain eleven of the allozymes but one allozyme, EST6-8 within the EST6-S class, is several times more common than any other. Variation in the frequency of this single allozyme can explain most of the latitudinal clines previously reported for the major EST6-F and EST6-S classes. Thermostability analyses of 52 of the Australian lines and 13 American lines reveal at least seven more EST6 variants within five of the allozymes, bringing the total number of variants to at least 21. Of the six allozymes for which more than one line was subjected to thermostability analyses, only EST6-8 could not be partitioned into additional variants. This corroborates a previous finding that two different isolates of the Est6-8 allele have identical DNA sequences and suggests that this allele, although now the most common, has nevertheless arisen relatively recently.

Alleles↗
PubMed1989

Molecular population genetics of structural variants of esterase 6 in Drosophila melanogaster.

Several lines of evidence indicate that natural selection operates between the major EST6-F and EST6-S allozymes of Drosophila melanogaster. In particular, consistent latitudinal clines and seasonal variation in their relative frequencies strongly suggest that they are not selectively equivalent in field populations. Several laboratory studies have found frequency-dependent fitness differences among the Est6-F and Est6-S genotypes. Moreover, the purified EST6-F and EST6-S allozymes differ in biochemical properties and the physiology of the enzyme, as a major component of the seminal fluid, suggests that these differences could affect reproductive aspects of fitness. However, molecular analyses reveal high levels of variation in the EST6 protein both within and between the EST6-F and EST6-S allozymes. Limited thermostability and more sensitive electrophoretic analyses reveal at least 17 variants of the two allozymes and sequence comparisons among 13 isolates of the Est6 gene reveal 16 nucleotide polymorphisms that would lead to amino acid differences. Two closely linked amino acid differences are strongly associated with the major difference between EST6-F and EST6-S; either or both of these are likely to cause the observed biochemical differences between EST6-F and EST6-S and may be the primary targets for the selection between these allozymes. The functional and adaptive significance of the other amino acid polymorphisms is unclear, although the data suggest that the EST6-8 haplotype within EST6-S has both arisen and proliferated relatively recently.

Alleles↗
PubMed1983

Blood-lead levels in patients with chronic liver diseases.

Blood-lead concentrations (Pb-B) were measured in 318 adult inpatients with chronic liver diseases. The Pb-B was highest (387 +/- 96 micrograms/l) in 102 patients with alcoholic liver disease without cirrhosis. The Pb-B was still high, but significantly lower in 60 patients with compensated alcoholic cirrhosis (342 +/- 100 micrograms/l) and in 72 patients with decompensated alcoholic cirrhosis (312 +/- 97 micrograms/l). This difference was in part due to a significant decrease of the hematocrit which fell from 44.4 +/- 4.9% to 42.4 +/- 27.2% and to 39.2 +/- 7.4% respectively. In patients with viral or cryptogenic liver diseases the Pb-B was 211 +/- 69 micrograms/l in 11 patients with chronic persistent hepatitis, 219 +/- 72 micrograms/l in 19 with chronic active hepatitis, 206 +/- 94 micrograms/l in 28 with compensated cirrhosis, and 226 +/- 98 micrograms/l in 26 with decompensated cirrhosis, without any significant difference. The Pb-B of the male patients showed no correlation to age, with the exception of 25 male patients with chronic persistent and active hepatitis (r = 0.626, P less than 0.001).

Adult↗
PubMed1983

[Lead exposure in the adult population non-occupationally exposed].

Lead is added into the environment by the production, use and deposited a variety of lead-containing materials. This pollution is increasing during the last years. The major source for the human intake of lead is the food chain. The people who very hardly drinks (especially wine) have been found have very high blood lead levels. 184 hospitalized patients for alcoholic liver diseases were examined and the Pb-B levels were 36,3 +/- 10,2 micrograms/100 ml. Smoking habits are another factor that increases the blood lead levels.

Alanine↗
PubMedDate not supplied

Relationships between blood lead concentration and aminolevulinic acid dehydratase in alcoholics and workers industrially exposed to lead.

Blood lead concentration (Pb-B), aminolevulinic acid dehydratase (ALAD), and gamma-GT were measured in 265 workers industrially exposed to lead and in 184 patients with liver disease resulting from alcohol consumption. The first group was divided according to alcohol use, i.e., nondrinkers, moderate drinkers, and heavy drinkers. The second group was divided according to the following criteria: hepatopatic without cirrhosis, hepatopatic with compensated cirrhosis, and hepatopatic with decompensated cirrhosis. Heavy drinkers who were industrially exposed had the highest Pb-B (40.4 +/- 14.6 micrograms/dl) and the lowest ALAD (22.2 +/- 9.1 U/L). The correlations between Pb-B and ALAD show no significant change with the increase of Pb-B. In the alcoholic group, 76 patients with alcoholic liver disease without cirrhosis had the highest Pb-B (40.3-9.1 micrograms/dl) and ALAD the lowest (18.6 +/- 7.7 U/L). The negative correlation between Pb-B and log ALAD disappeared completely in individuals with Pb-B that exceeded 50 micrograms/dl, independent from the seriousness of illness.

Adult↗