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R Antonini

Publications and source records attributed to R Antonini.

At least 19 recordsLinked to original sources
PubMed1994

Simultaneous high-performance liquid chromatographic determination of adenosine and dopamine in rat striatal tissue with combined ultraviolet absorbance and electrochemical detection.

A method is described for the simultaneous determination of biogenic amines, adenosine and their metabolites in rat striatal tissue using high-performance liquid chromatography with ultraviolet spectrophotometric and electrochemical detection. Peaks in the chromatograms of striatal tissue extracts were identified by retention times and by on-line analysis of peak spectra for adenosine and its metabolites, and by comparing current ratios of the dual-electrode coulometric detector for monoamines and metabolites. The assay gives a linear response over the concentration range of 0.15-0.60 micrograms/ml for biogenic amines, 0.5-2.0 micrograms/ml for serotonin, 5-20 micrograms/ml for hypoxanthine, adenosine and N-methyladenosine, and 10-40 micrograms/ml for inosine. The limit of detection for striatal homogenates was 3.5 ng/g for monoamines, 9 ng/g for serotonine, 140 ng/g for hypoxanthine, 290 ng/g for inosine and 80 ng/g for adenosine. The recovery ranged from 88.5% for vanillylmandelic acid to 110.3% for dopamine. The method was used to measure biogenic amines, adenosine and related metabolites in rat striatal tissues.

Adenosine↗
PubMed1991

A form of familial hypobetalipoproteinaemia not due to a mutation in the apolipoprotein B gene.

Familial hypobetalipoproteinaemia (FHBL) is a dominant disorder of lipoprotein metabolism characterized by levels of apolipoprotein B-carrying lipoproteins (VLDL, IDL and LDL) which are 50% of the normal levels in the heterozygotes and almost absent in the homozygotes. Several reports have recently shown that the underlying defect in FHBL involves different mutations in the apo B gene which lead to reduced levels of apo B mRNA or to the production of truncated forms of apo B having either a lower synthetic rate or a higher catabolic rate than normal apo B. We here present a three-generation family with several FHBL members in which the linkage analysis shows absence of co-segregation between apo B gene alleles and the hypocholesterolaemic phenotype. We conclude that a dominantly transmitted mutation in a gene other than that for apo B is responsible for the low plasma cholesterol levels.

Adult↗
PubMed1991

[External services].

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Emergency Medical Services↗
PubMed1990

Serum lipoprotein pattern variations in dementia and ischemic stroke.

Blood levels of triglycerides, total cholesterol, isolated lipoprotein fractions (VLDL-LDL- and HDL-cholesterol) and apoproteins (Apo-A1 and Apo-B) were examined in multi-infarct dementia, senile dementia of the Alzheimer type, ischemic stroke associated with carotid atherosclerosis and in control subjects. Forty patients divided into 10 consecutive patients for each group were studied. Alzheimer patients showed mean total cholesterol and Apo-B values significantly higher than control subjects. Apo-B was significantly higher in stroke patients than in controls. The mean lowest HDL-cholesterol (HDL-c) value was observed in stroke patients. No significant differences in mean HDL-c levels were found between patients with multi-infarct and Alzheimer dementia.

Aged↗
PubMed1990

Variation at the apolipoprotein (apo) AI-CIII-AIV gene cluster and apo B gene loci is associated with lipoprotein and apolipoprotein levels in Italian children.

We have used RFLPs of the apolipoprotein (apo) B gene and apo AI-CIII-AIV gene cluster to estimate the genetic contribution of variation at these loci to the variability of plasmid lipid, lipoprotein, and apolipoprotein levels in 209 children from Sezze in central Italy. The sample was randomly divided into group I (107 children) and group II (102 children). Four site polymorphisms (PvuII, XbaI, MspI, and EcoRI) of the apo B gene and five site polymorphisms (XmnI, PstI, SstI, PvuII-CIII, and PvuII-AIV) of the apo AI-CIII-AIV gene cluster were examined in group I children. After adjustment for gender, age, and body-mass index, polymorphisms at both gene loci (PvuII-B, PvuII-CIII, and PvuII-AIV) were associated with significant effects on the levels of plasma apo AI, apo B, or high-density lipoprotein-cholesterol. RFLPs that showed significant effects in group I were genotyped in group II. All three polymorphisms were associated with similar effects on apolipoprotein levels, though for all RFLPs the magnitude of the effects was smaller in the group II children and only statistically significant for the effect of the PvuII-B genotype on apo AI levels. In the total sample of 209 children 7.4% of the sample variance in apo AI levels was explained by variation associated with the apo B PvuII-B RFLP. In addition, the PvuII-B RFLP was associated with significant effects on plasma apo B levels and explained 5.7% of the sample variance. The PvuII-CIII and PvuII-AIV polymorphisms were both associated with differences in apo AI levels, explaining 3.7%-5.7% of the sample variance. Taken together, the three PvuII polymorphisms explained 17.7% of the phenotypic variance in apo AI levels. There was significant evidence for an effect of nonlinearity of the PvuII-CIII genotypes on apo AI levels, with the individuals heterozygous for the polymorphism having the highest apo AI levels. No evidence of interaction between genotype and gender, age, and body-mass index was shown by covariance analysis. The molecular explanation of this effect is unclear. Our data show that variation at both the apo AI-CIII-AIV and apo B loci are associated with lipoprotein and apolipoprotein levels in this sample of Italian children.

Alleles↗
PubMed1989

[Oncocytoma of the kidney: a diagnostic and therapeutic dilemma].

Renal oncocytic tumours are uncommon and controversial in both their diagnosis and therapy. The need for correct cytological diagnosis is emphasised and total nephrectomy proposed as the elective surgical treatment owing to the real possibility of malignancy and multicentric diffusion. Conservative management should be reserved for bilateral tumours or where the tumour occurs in a solitary kidney.

Adenoma↗
PubMed1988

Serum thiocyanate levels as an objective measure of smoking habits in epidemiological studies.

The relationship between smoking habits and plasma thiocyanate levels has been evaluated in four adult samples of the general population containing men and women aged 20-84 and in a sample of 11-year-old non-smoking children of both sexes, for a total of 7577 individuals. Mean levels of plasma thiocyanate was found be approximately 20 mumol/l in children, 30 mumol/l in non-smoking adults and increasingly higher in smoking adults. The slopes of the regression equations of thiocyanate on cigarettes smoked per day range from 3.041 to 5.740, with correlation coefficients of from 0.638 to 0.809. In another occupational sample of 2802 men aged 46 to 65, where the correlation coefficient (between cigarette consumption and thiocyanate) was only 0.49, plasma thiocyanate was a better predictor of 4 year fatal events than cigarette consumption, 4 other covariates being considered in the same multivariate model.

Adult↗
PubMed1986

Plasma lipid lipoproteins and biliary lipid composition in female gallstone patients.

The relationships between biliary lipid composition and cholesterol or triglyceride concentration in plasma lipoprotein fractions (i.e., very-low density, low-density, high-density, HDL2 and HDL3) have been studied in normolipaemic female gallstone patients. Univariate and multivariate stepwise statistical analyses were used to correlate biliary-tested variables against lipid lipoprotein concentration. Cholesterol saturation index was found to be positively and independently associated with total triglycerides, very-low-density lipoprotein triglycerides, very-low-density lipoprotein cholesterol and furthermore, negatively, with HDL3-cholesterol. Percent biliary deoxycholate was positively correlated with both cholesterol saturation index and plasma very-low-density cholesterol or triglycerides. Neither cholesterol saturation index nor percent biliary deoxycholate showed any correlation with total cholesterol, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, HDL2-cholesterol. The present findings suggest a linkage between biliary deoxycholate, biliary cholesterol saturation and plasma very-low-density lipoprotein levels in gallstone patients. Furthermore, since the lipoprotein risk factors for coronary heart disease showed no correlation with cholesterol saturation index, these results were considered a biochemical proof against the supposed association between coronary heart disease and gallstone disease.

Adult↗
PubMed1985

Plasma cholesterol response to a change in dietary fat intake: a collaborative twin study.

The rise of plasma cholesterol in response to an increase from 8 to 22.3% in saturated fatty acid of total intake was studied by comparing the concordance of change in pairs of young English and Italian monozygotic (33 pairs) and dizygotic (22 pairs) twins. LDL and total cholesterol rose about 0.6 mmol/l. All methods of analyses showed a marked genetic component influencing total and LDL cholesterol level. However, the genetic component of the increase in LDL and total cholesterol levels was small in Italy and absent in England. These results suggest that the response of plasma cholesterol to this dietary change is largely determined by environmental factors rather than inheritance.

Adolescent↗
PubMed1978

Uterine blood flow and prostaglandin levels in ovariectomized rabbits.

Blood flow (measured by radioactive microspheres) through the uteri of ovariectomized rabbits increased significantly by 2 h, was lower at 4 and 8 h, and returned to control values by 24 h after an injection of 25 microgram oestradiol-17beta. Blood flow through the kidneys was not affected. Concentrations of PGF and PGE in uterine vein blood were elevated after oestrogen treatment. PGF values were significantly greater than control. PGE concentrations, while elevated, were not significantly different from control, although the pattern of release was similar to that of PGF. Pretreatment of animals with progesterone or L11204, or concurrent treatment with indomethacin did not modify the blood flow through the uterus. It is concluded that the increased uterine blood flow seen after oestrogen treatment is not related to prostaglandin production.

Animals↗
PubMed1977

Open abdomen liver biopsy by a modified one-second technic.

With the purpose of facilitating liver biopsy during upper abdominal procedures, an adaptation of the percutaneous one-second needle biopsy technic is proposed. A simple device, consisting of a three-way deviator, allows the utilization of the standard needles for percutaneous biopsy. The entire procedure requires from 10 to 30 seonds. Large caliber needles from 1.6 to 2.0 mm are recommended. Complications are practically nonexistent.

Abdomen↗
PubMed1977

Cyclic nucleotides and prostaglandins (PGs) produced by the rabbit oviduct: effects of estrogen treatment.

Levels of cyclic AMP and cyclic GMP have been measured in oviducts of rabbits killed 68 hr after injection of human chorionic gonadotrophin (HCG) to induce ovulation. cAMP and cGMP levels were higher in the isthmus than in the ampulla. Estrogen treatment given at the same time as HCG increased cGMP levels. Levels of PGE and PGF in blood draining the oviduct were low and showed no effect of estrogen treatment at 68 hr after HCG.

Animals↗
PubMed1977

Fertility following microsurgical removal of the ampullary-isthmic junction in rabbits.

The role of the ampullary-isthmic junction (AIJ) in fertility was investigated in the rabbit by using microsurgical tuboplastic techniques. Microsurgical transection or resection of the AIJ failed to alter fertility significantly. Nine of ten rabbits which underwent unilateral transection of the AIJ became pregnant on the operated side and eight of the ten became pregnant on the unoperated control side. Of the ten rabbits which underwent unilateral AIJ resection, all became pregnant bilaterally. The results of this study indicate that the AIJ is not necessary for normal fertility in the rabbit.

Animals↗
PubMed1976

The hormonal control of the guinea pig corpus luteum during early pregnancy.

Forty guinea pigs were divided into two groups, pregnant and nonpregnant, and were operated upon on days 10, 12, 14, and 16 of the ovarian cycle or of pregnancy. Blood was obtained from the utero-ovarian vein, and prostaglandin F2alpha (PGF2alpha), prostaglandin E (PGE), progesterone, and estrogen content was assayed by radioimmunoassay. Increased levels of PGF2alpha preceded a drop in progesterone levels in nonpregnant animals, reflecting luteolysis. In pregnant animals, the level of PGF2alpha remained low, and progesterone levels increased. PGE levels were similar in the two groups. These results suggest that the low PGF2alpha levels seen during early pregnancy are related to corpus luteum rescue.

Animals↗