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A Calì

Publications and source records attributed to A Calì.

At least 19 recordsLinked to original sources
PubMed2004

Validation and comparison of analytical methods for the determination of histamine in tuna fish samples.

Histamine is a degradation product of the bacterial decarboxylation of the amino acid histidine, which is present in large amounts in fish tissues of the Clupeidae and Scombridae families and its presence is an indicator of good manufacturing practices and of the state of preservation of some food. A capillary electrophoresis and high-performance liquid chromatography method with diode arrays detection (HPLC-DAD) were compared and validated: no laborious pre-treatment, no clean up and no derivatization was necessary. In both techniques the correlation coefficient exceeded 0.999 for all the analyses carried out during validation. The limit of detection and the limit of quantitation are 1 and 2 mg/kg, respectively, for high-performance liquid chromatography and 0.5 and 1 mg/kg, respectively, for capillary electrophoresis. Good recoveries were observed for the histamine under investigation at all spiking levels and average recoveries were higher than 92% with the relative standard deviation less than 4% for high-performance liquid chromatography and average recoveries were higher than 85% with the relative standard deviation less than 3% for capillary electrophoresis.

Animals↗
PubMed2004

Determination of biogenic amines in fish tissues by ion-exchange chromatography with conductivity detection.

Some biogenic amines, such as putrescine, cadaverine, spermidine and histamine, have been found to be useful as quality indices for the decomposition of fish, so research on the simultaneous analysis of various biogenic amines in food is of interest and importance. The intake of histamine may cause an allergic intoxication known as "scombroid poisoning" while secondary biogenic amines can potentiate the toxicity of histamine and in addition can react with nitrite to form carcinogenic nitrosamines. A new method for the simultaneous determination of underivatized biogenic amines based on ion-exchange chromatography with conductivity detector has been developed. The proposed method offers a number of advantages over previous pulsed amperometric detection and integrated pulsed amperometric detection methods such as simpler extraction procedure and sharp peaks. Separations were performed on a new low hydrophobic weak cation-exchange analytical column. This technique is simple, rapid and useful for routine checks in repetitive analyses.

Animals↗
PubMed2001

New mutations inactivating transferrin receptor 2 in hemochromatosis type 3.

Hereditary hemochromatosis usually results from C282Y homozygosity in the HFE gene on chromosome 6p. Recently, a new type of hemochromatosis (HFE3) has been characterized in 2 unrelated Italian families with a disorder linked to 7q. Patients with HFE3 have transferrin receptor 2 (TFR2) inactivated by a homozygous nonsense mutation (Y250X). Here the identification of 2 new TFR2 mutations is reported. In a large inbred family from Campania, a frameshift mutation (84-88 insC) in exon 2 that causes a premature stop codon (E60X) is identified. In a single patient with nonfamilial hemochromatosis, a T-->A transversion (T515A), which causes a Methionine-->Lysine substitution at position 172 of the protein (M172K), has been characterized. TFR2 gene gives origin to 2 alternatively spliced transcripts-the alpha-transcript, which may encode a transmembrane protein, and the beta-transcript, a shorter, possibly intracellular variant. Based on their positions, the effects of the identified mutations on the 2 TFR2 forms are expected to differ. Y250X inactivates both transcripts, whereas E60X inactivates only the alpha-form. M172K has a complex effect: it causes a missense in the alpha-form, but it may also prevent the beta-form production because it affects its putative initiation codon. Analysis of the clinical phenotype of 13 HFE3 homozygotes characterized at the molecular level has shown a variable severity, from nonexpressing patients to severe clinical complications. The identification of new mutations of TFR2 confirms that this gene is associated with iron overload and offers a tool for molecular diagnosis in patients without HFE mutations.

Adolescent↗
PubMed2001

Clinical and molecular characterisation of 80 patients with 5p deletion: genotype-phenotype correlation.

The majority of deletions of the short arm of chromosome 5 are associated with cri du chat syndrome (CdCS) and patients show phenotypic and cytogenetic variability. To perform a genotype-phenotype correlation, 80 patients from the Italian CdCS Register were analysed. Molecular cytogenetic analysis showed that 62 patients (77.50%) had a 5p terminal deletion characterised by breakpoint intervals ranging from p13 (D5S763) to p15.2 (D5S18). Seven patients (8.75%) had a 5p interstitial deletion, four (5%) a de novo translocation, and three (3.75%) a familial translocation. Of the remaining four patients, three (3.75%) had de novo 5p anomalies involving two rearranged cell lines and one (1.25%) had a 5p deletion originating from a paternal inversion. The origin of the deleted chromosome 5 was paternal in 55 out of 61 patients (90.2%). Genotype-phenotype correlation in 62 patients with terminal deletions highlighted a progressive severity of clinical manifestation and psychomotor retardation related to the size of the deletion. The analysis of seven patients with interstitial deletions and one with a small terminal deletion confirmed the existence of two critical regions, one for dysmorphism and mental retardation in p15.2 and the other for the cat cry in p15.3. Results from one patient permitted the cat cry region to be distally narrowed from D5S13 to D5S731. Furthermore, this study lends support to the hypothesis of a separate region in p15.3 for the speech delay.

Adolescent↗
PubMed2000

The gene TFR2 is mutated in a new type of haemochromatosis mapping to 7q22.

Haemochromatosis is a common recessive disorder characterized by progressive iron overload, which may lead to severe clinical complications. Most patients are homozygous for the C282Y mutation in HFE on 6p (refs 1-5). A locus for juvenile haemochromatosis (HFE2) maps to 1q (ref. 7). Here we report a new locus (HFE3) on 7q22 and show that a homozygous nonsense mutation in the gene encoding transferrin receptor-2 (TFR2) is found in people with haemochromatosis that maps to HFE3.

Animals↗
PubMed1999

FISH characterization of two supernumerary r(1) associated with distinct clinical phenotypes.

Only a few reports on supernumerary r(1) chromosomes associated with a clinical phenotype have been published. We describe two unrelated patients with congenital malformations and developmental delay who were found to have a de novo supernumerary r(1) in 50% (Case 1) and 80% (Case 2) of the examined cells. Conventional cytogenetic techniques (QFQ, CBG, and DA-DAPI), complemented by fluorescence in situ hybridization studies using alpha satellite probes, showed that both small marker chromosomes (SMCs) primarily consisted of the centromere and heterochromatin of chromosome 1, a conclusion that was also supported by chromosome 1 painting. In an attempt to establish phenotype-genotype correlations, a further investigation was performed using YACs mapped to the chromosome 1 pericentromeric region. A fluorescent signal was evident after hybridization with Y934G9 (1q21) in Case 1 and Y959C4 (1p11.1-12) in Case 2. Partial trisomy of unique sequences flanking pericentromeric sequences is shown to underlie the clinical phenotype in both patients. This evidence should be taken into account when SMCs are ascertained, particularly in prenatal diagnosis.

Abnormalities, Multiple↗
PubMed1997

Effect of octreotide pretreatment on surgical outcome in acromegaly.

Pretreatment with octreotide (OCT) in acromegaly has been reported to improve surgical outcome. The objective of this study was to analyze retrospectively the effects of a 3- to 6-month presurgical treatment with OCT in acromegalics focusing on electrocardiographic (ECG) records, blood pressure levels, glucose and lipid profile, tumor size and consistency, easy tumor removal at surgery, and morphological findings at pathology. Fifty-nine patients with acromegaly who were undergoing surgical treatment were studied randomly before surgery; 37 patients were untreated, and 22 were treated with OCT at doses ranging 150-600 micrograms/day for 3-6 months. At study entry, untreated and OCT-treated patients had similar circulating GH and insulin-like growth factor I (IGF-I), glucose, and cholesterol levels as well as prevalence of overt diabetes mellitus, hypertension, and ECG abnormalities. In untreated and OCT-treated patients, respectively, radiological imaging documented microadenoma in 0 and 1, intrasellar macroadenoma in 10 and 6, intra- and suprasellar macroadenoma in 18 and 11, invasive macroadenoma in 9 and 4 patients. Before surgery, serum GH and IGF-I levels significantly decreased in the 22 OCT-treated acromegalics, and in 5 of them, a significant shrinkage was documented. ECG abnormalities disappeared in 7 of 11 (63.6%) OCT-treated patients. In 3 of the 7 patients with diabetes mellitus, treatment with OCT together with low carbohydrate intake normalized blood glucose levels, whereas in 2 patients, insulin could be replaced by oral antidiabetics, and in 2 patients, the insulin dose was reduced. Presurgical blood glucose, total cholesterol and triglyceride levels, as well as systolic (145.2 +/- 3.4 vs. 132.9 +/- 2.5 mm Hg; P < 0.01) and diastolic (94.3 +/- 1.7 vs. 84.3 +/- 1.6 mm Hg; P < 0.001) blood pressure levels were significantly higher in untreated than in OCT-treated patients. Two weeks after surgery, circulating GH and IGF-I levels were normalized in 11 untreated (29.7%) and 12 OCT-treated (54.5%) patients (P < 0.005, by chi 2 test). Macroscopically, no difference was found between untreated and OCT-treated adenomas, whereas at pathology, a significant increases in cellular atypia (31.6% vs. 19.2%; P < 0.05) was found in OCT-treated adenomas. One patients in the untreated group died from cardiorespiratory arrest during the early postoperative period. Finally, the average duration of hospitalization after operation was longer in untreated than in OCT-treated patients (8.6 +/- 0.7 vs. 5.6 +/- 0.5 days). We conclude that a 3- to 6-month treatment with OCT before surgery for GH-secreting adenoma improved clinical conditions and surgical outcome and reduced the duration of hospitalization after operation.

Acromegaly↗
PubMed1996

Clinicopathological and genetic studies of two further Italian families with cerebral autosomal dominant arteriopathy.

We report on two Italian families with an early-adult onset autosomal dominant disorder, characterized by leukoencephalopathy, migraine, psychiatric disturbances, stroke and dementia. These findings fulfill the diagnostic criteria for cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) syndrome. Moreover, to confirm the CADASIL gene location to 19p12, we performed a linkage analysis with four microsatellite markers. The results of the genetic study gave positive but not significant lod scores, indicating only weak evidence of a linkage with 19p12. In one autopsy case, we found extensive ischemic changes due to the selective involvement of the small muscular arteries of the cerebral white matter. The lesions consisted of a thickening of the media with deposition of granular eosinophilic material. Ultrastructural examination of the arterial walls showed graded damage to smooth muscle cells, mostly of the longitudinal layer, and an abnormal proliferation of basal lamina components. Immunocytochemical analysis showed strong reactivity using antibodies to collagen IV and smooth myosin proteins. The results suggest a primary involvement of the smooth muscle cells of small cerebral arteries, with a secondary alteration of basal lamina components and elastic tissue.

Adult↗
PubMed1993

Histological findings and evidence of lipid conjugated dienes and malonyldialdehyde in human fetal aortas.

Recent evidence strongly suggests that peroxidative modification of lipids may play a significant role in atherogenesis. In our present research, we investigated if the oxidative stress mediated by oxygen free radicals was a pathophysiologic condition that occurred in the early stages of human development. Thus the aim of this research was to examine lipid peroxidation in human fetal aortas. Human fetal aortas and proximal iliac arteries (n = 8) were obtained from fetuses aged 7 +/- 2 months, immediately after autopsy. Lipids from the initial fatty streak lesions (LFS) and the vessels uninvolved (LUV) were extracted by the chloroform/methanol method. Lipid peroxidation levels were measured by two different methods: determination of lipid conjugate dienes (the spectrum trend was recorded from 320 to 200 nm with a spectrophotometer) and malonyldialdehyde (MDA) content (TBA method). We observed that lipid conjugated dienes were present in LFS, but not in LUV, with a characteristic absorption peak at 233 nm. In addition, MDA levels were significantly higher when the LFS = 3.85 +/- 0.91 nmol than when the LUV = 0.41 +/- 0.12 nmol (p < 0.001 versus LUV). The presence of lipid peroxidation in our samples could be mediated by free radical production in the first stages of human development. Thus these data suggest that LFS peroxidation mediated by free radicals occurs in the vascular circulation in the early stages of human development. This could influence the progression of vascular damage and atherosclerotic disease.

Aorta↗
PubMed1991

[Clinico-pathological evaluation of patients with homozygous familial hypercholesterolemia].

The authors have studied 8 patients with Homozygous Familial Hypercholesterolemia (FHO) an autosomal genetic dominant disease due to mutation of the gene encoding a cell surface receptor for LDL. Anatomic and pathologic abnormalities caused by LDL-cholesterol and B-Apolipoprotein high plasma levels were found. We also measured malondialdehyde levels in plasma and atherosclerotic plaques of the only autoptic case observed. MDA-levels are an index of lipid peroxidation. Cutaneous xanthomatosis lesions and severe cardiovascular disease were also present.

Adult↗
PubMedDate not supplied

3D angiography in the evaluation of intracranial aneurysms before and after treatment. Initial experience.

PURPOSE: The aim of the study is to evaluate the advantages of 3D angiography as compared to 2D angiography in assessing intracranial aneurysms before and after treatment and, in particular, in selecting and planning the correct treatment. MATERIALS AND METHODS: Thirty intracranial aneurysms were retrospectively reviewed before and after treatment. The study population consisted of 12 men and 18 women (age range: 35-77 years; mean age: 58 years). Eighteen aneurysms were treated surgically, 10 endovascularly and 2 with combined treatment. The 2D and 3D findings before and after treatment were compared, and the pre-treatment angiographic images were compared with surgical findings. The following parameters were assessed and compared: aneurysmal sac and neck size, vascular involvement and evaluation of post-treatment residual mass. RESULTS: On the 2D DSA images, visualisation of the sac and neck was optimal in 45% and 15% of cases, adequate in 10% and 35% of cases and inadequate in 5% and 50% of cases, respectively. On the 3D DSA images, visualisation of the sac and neck was optimal in 100% of cases. Three-dimensional DSA was able to detect 8 aneurysms with vessel involvement in all cases (100%). Of these, four (50%) went undetected on 2D DSA; in two cases, two-dimensional DSA erroneously detected the presence of vascular involvement (false positive). Three-dimensional angiography proved superior to 2D angiography in the evaluation of the residual aneurysms treated with clipping. Finally, 3D DSA was able to reduce the number of radiographic projections, the quantity of contrast medium, the time and associated risks necessary for a precise evaluation of the aneurysm. CONCLUSIONS: In our first experience, 3D DSA proved useful in reducing the risks and diagnostic time as well as in selecting and planning the treatment. Moreover, it improved the operating conditions of both surgical and endovascular treatment. Technological advances in this field will enable the optimisation of the technique in terms of anatomical detail and reconstruction time.

Adult↗