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Biomedical subjects

R Gatti

Publications and source records attributed to R Gatti.

At least 109 records · Page 6Linked to original sources
PubMed1995

Infantile sialic acid storage disease: biochemical studies.

Infantile free sialic acid storage disease (ISSD), is an inherited metabolic disorder characterized by hyperexcretion of free sialic acid in the urine and by its storage in the lysosomes of different tissues. In order to obtain more reliable data on the amount of total and free sialic acid, we analyzed the urine, brain, cerebellum, liver, spleen, and kidneys from a 3-month-old baby who died with a diagnosis of ISSD. The lysosomal nature of the disease was confirmed by an electron microscopic study of cells in culture. No significant abnormalities were found involving cholesterol, total phospholipids, glycolipids, and gangliosides in the tissues examined. However, differences in the tissue distribution of individual glycolipids and gangliosides were observed. The amount of free and total sialic acid was markedly increased, due to the storage of free sialic acid accompanied by its hyperexcretion in the urine. These results demonstrate and confirm that only acid monosaccharide transport from the lysosome compartment is involved in the pathogenesis of ISSD.

Brain Chemistry↗
PubMed1995

The CEPH consortium linkage map of human chromosome 11.

The CEPH consortium framework map of chromosome 11 is presented. The map was generated from CEPH family DNAs with 181 probe/enzyme combinations contributed by 20 laboratories. Seventy-seven of the loci are defined by microsatellite polymorphisms that can be typed by the PCR. A total of 42 loci have been placed on the map with likelihood support of at least 1000:1. The female, male, and sex-average maps extend for 179.6, 110.8, and 145.3 cM, respectively. The largest interval on the sex-average map is less than 11 cM, and the average distance between uniquely placed loci is 4 cM. The genotypic data obtained for map construction have been used to identify the positions of crossovers on the chromosomes of CEPH family children, allowing the localization of new markers without computationally intensive likelihood models and providing a basis for efficient extension of the linkage map to higher resolution.

Adult↗
PubMed1995

Characterization of apoptotic phenomena induced by treatment with L-asparaginase in NIH3T3 cells.

The treatment of NIH3T3 cells with L-asparaginase causes a complete and reversible growth arrest with a decrease of cell number in the first 2 days. The enzyme induces impressive morphological changes that have been studied exploiting eosin in fixed cells and calcein in intact cells as sources of fluorescence for confocal microscopy. The first changes are observed after 12 h of treatment and the process is complete after 48 h. Both nucleus and cytoplasm shrink, while cells round and lose processes. Eventually most cells break; several debris include strongly hematoxylinic bodies negative for eosin fluorescence. Some cells neither round nor break in fragments. Throughout the process cells and fragments retain calcein fluorescence, thus indicating the integrity of the cell membrane. A rapid depletion of the intracellular pools of both glutamine and glutamate occurs in treated cells, followed by a decrease in DNA and protein syntheses, while the cell content of ATP, the transmembrane gradient of sodium, and the active transport of amino acids are scarcely affected. It is concluded that (i) L-asparaginase induces an apoptotic process in NIH3T3 cells that is forerun by a marked intracellular depletion of glutamate and glutamine; and (ii) although the enzyme completely suppresses cell proliferation, only a subset of cells undergoes apoptosis upon treatment. These findings provide a model for the characterization of factors that determine cell sensitivity to the effects of L-asparaginase.

3T3 Cells↗
PubMed1995

An AT-deletion causing a frameshift in the arylsulfatase A gene of a late infantile metachromatic leukodystrophy patient.

A metachromatic leukodystrophy (MLD) patient affected with the late infantile form was found to be homozygous for an AT-deletion (2324delAT) in the arylsulfatase A gene. The mutation causes a frameshift at the beginning of exon 8 leading to an early termination codon. The parents and unaffected brother of the patient were heterozygous for the microdeletion. The mutation was not detected in another 31 MLD Italian patients. No aberrant transcript caused by the mutation was revealed by the reverse transcription-polymerase chain reaction method.

Amino Acid Sequence↗
PubMed1995

Flexible electrogoniometers: kinesiological advantages with respect to potentiometric goniometers.

Unlike conventional potentiometric goniometers, flexible electrogoniometers do not suffer from any alignment problems with respect to the joint axis. We hypothesized that flexible goniometers provide more valid measurements in that they avoid some biomechanical pitfalls. With both devices simultaneously we measured the movements of dorsal flexion of the ankle and flexion of the knee in three healthy subjects. In the various subjects, this comparison showed that the flexible goniometers signalled ankle excursion greater by 19-40% with the foot remaining in neutral position or being simultaneously pronated, and lower by 10-21% with the foot being simultaneously supinated. At the knee the flexible goniometers signalled a flexion greater by 24-32%, with respect to potentiometric goniometers. Biomechanical considerations support the validity of records taken with flexible goniometers, potentiometric measures being biased by (a) multijoint, multiplane motions underlying foot dorsal flexion, and (b) multiaxis motion underlying knee flexion RELEVANCE: In measurements of angles between adjacent body segments, flexible goniometers should be preferred to potentiometric goniometers despite their higher cost. Flexible goniometers not only are more practical: more importantly, they provide a valid measure of relative orientations in one plane, regardless of the number and different concurrent motions of the underlying joints.

Journal Article↗
PubMed1995

Analysis of aliphatic dicarboxylic acids in pharmaceuticals and cosmetics by liquid chromatography (HPLC) with fluorescence detection.

2-Bromoacetyl-6-methoxynaphthalene has been found to be a useful prechromatographic fluorescent labelling reagent for the analysis of dicarboxylic acids. The derivatization reaction of azelaic acid and meglutol with this reagent yieded stable and highly fluorescent diesters which could be analysed by reversed-phase HPLC with fluorescence detection. According to the nature of the sample, the derivatization reaction could be carried out in acetonitrile or in an aqueous micellar system. The proposed methods proved to be suitable for the quality control of various complex pharmaceutical and cosmetic formulations of the azelaic acid and meglutol.

Chromatography, High Pressure Liquid↗
PubMed1995

Analysis of pharmaceutical creams: a useful approach based on solid-phase extraction (SPE) and UV spectrophotometry.

Solid-phase extraction (SPE) using C-18, diol and ion-exchange sorbents followed by UV spectrophotometric (conventional and derivative mode) assay was applied to the analysis of basic, acidic and neutral drugs commercially available in creams. A representative set of drugs (promethazine, chlorhexidine, benzydamine, ketoprofen, ibuprofen, fentiazac, piroxicam, fluorouracil, crotamiton and hydrocortisone acetate) was selected, and for each drug the appropriate SPE conditions (adsorption, washing and elution) were investigated to obtain a practical and reliable sample clean-up. It was shown that the developed SPE procedures were capable of removing interfering cream components (excipients including preservatives) allowing accurate spectrophotometric analyses to be performed. In some applications, derivative spectrophotometry was advantageous over the conventional absorption mode with respect to higher selectivity and versatility.

Pharmaceutical Preparations↗
PubMed1995

Mutations in fucosidosis gene: a review.

Fucosidosis is an autosomal recessive disorder caused by a deficiency of alpha-L-fucosidase. Up to now 79 cases have been described and several others identified but not yet published. The higher incidence of the disease is in Italy, where nearly 20 patients have been identified. Fourteen disease-causing mutations have been detected and four of them, Q422X, G60D, E375X, P141fs are present in more than 70% of the forty patients studied. In Italian patients, only seven mutations have been described and P141fs and G60D mutations are present in more than 50% of the cases. The P141fs mutation is absent in other ethnic groups. It has been impossible to establish genotype-phenotype correlation so far and the clinical variability of the disease cannot be explained only by genetic heterogeneity.

DNA↗
PubMed1995

Reliability of short-term esophageal pH monitoring versus 24-hour study.

The child's discomfort and the cost of overnight hospitalization are clear disadvantages of prolonged esophageal pH monitoring. The aim of this study was to verify the reliability of short recording versus 24-h testing in a pediatric series with symptoms suggestive of gastroesophageal reflux (GER) disease. A 24-h pH monitoring performed on 160 patients with either gastroenterological symptoms (n = 61), respiratory problems (n = 58), or emesis plus respiratory problems (n = 41) was reviewed. Regardless of clinical presentation, children were also classified according to age: < 12 months (n = 39), 12-71 months (n = 81), and 72-168 months (n = 40). A diurnal fraction of 6 h, including at least 2 h after a meal, was compared to the entire 24-h recording in all groups with respect to the reflux index (RI) (sum of the periods with pH < 3.9 expressed as percentage of time) and reflux/h. RIs of > 10% were considered positive in patients < 1 year of age, whereas RIs of > 5% were considered positive in other age groups. Negative predictive values of the short recording RI ranged from 71 to 90%. Positive predictive values ranged from 50 to 83%; it was unreliable for children < 12 mos (50%) and patients with emesis plus respiratory problems (64%), who were, significantly, the youngest. Reflux/h values were not in agreement for the same groups. Absence of agreement was found if the absolute value of RI was considered.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1995

A rare G6490-->A substitution at the last nucleotide of exon 10 of the glucocerebrosidase gene in two unrelated Italian Gaucher patients.

Mutation screening of the glucocerebrosidase gene by SSCP analysis revealed an abnormal pattern of exon 10 in two unrelated Italian Gaucher patients. Direct sequencing of the mutated samples identified a G6490-->A transition. The same mutation has been described before in a Japanese patient with Gaucher disease type III. The clinical phenotype of our patients was type I in one whose second allele carried the N370S mutation and type II in the other one with a L444P mutation. In this latter the G6490-->A substitution cancels a normal Msp I site, while on the opposite chromosome the T6433-->C mutation (L444P) introduces a new Msp I site. Thus, digestion with Msp I of the amplified exon 10 is a useful method for identifying the two mutations simultaneously.

Adenine↗
PubMed1994

Putative tumor-suppressor gene on chromosome 11 is important in sporadic endocrine tumor formation.

Endocrine tumors arising sporadically or as a manifestation of the multiple endocrine neoplasia type I syndrome (MEN I) have been shown to have mutations on chromosome 11. These mutations can be detected at the molecular level by loss of heterozygosity (LOH) for DNA markers from chromosome 11. This study represents one of the largest collections of sporadic endocrine tumors in which LOH was systematically assessed on chromosome 11 for the loci flanking the proposed MEN I region. DNA was isolated from 39 endocrine tumors and probed with 7 DNA probes spanning the region of chromosome 11q13 from the loci PYGM to INT-2. Eleven tumors demonstrated LOH at any two loci in this region. The remaining 28 tumors showed no LOH or were noninformative at these loci. Thus, nearly 30% of these tumors showed LOH in the region (from PYGM to INT-2) that is thought to contain the MEN I gene(s). Previous studies of sporadic endocrine tumors have suggested that these tumors may arise via the same mechanism as tumors of the MEN I syndrome. Namely, these sporadic tumors are thought to result from mutations leading to genetic loss on the long arm of chromosome 11, thereby inactivating a possible tumor-suppressor gene (or genes). These findings strongly support the hypothesis that sporadic pancreatic endocrine tumors share a similar etiology of tumorigenesis with tumors of the MEN I syndrome, which principally involves deletion of a tumor-suppressor element (or elements).

Blotting, Southern↗
PubMed1993

Report on two patients with Costello syndrome and sialuria.

We report on 2 unrelated patients with Costello syndrome. The first is a 5-year-old girl with "coarse" face, nasal papillomata, redundant skin of feet and hands, hyperextensible hand and finger joints, curly hair, feeding problems due to oral motor apraxia, growth and psychomotor retardation. The second is a 3-year-old boy with "coarse" face, loose skin on hands and feet, curly hair, oral motor apraxia, severe growth and psychomotor retardation. In both patients urine sialic acid levels were found to be repeatedly high. The meaning of this biochemical abnormality is discussed.

Abnormalities, Multiple↗
PubMed1993

Mucopolysaccharidosis: thickening of dura mater at the craniocervical junction and other CT/MRI findings.

Cranial CT and/or MRI imaging of 8 patients with mucopolysaccharidosis (MPS) was retrospectively evaluated. Two patients had MPS IH, 1 had MPS IS, 1 had MPS IVA and 4 had MPS IV. CT and MRI showed thickening of dura mater at the cranio-cervical junction, causing narrowing of the subarachnoid space, in all the patients examined. Spinal cord compression was detected in 4 patients. Other findings were: white matter alterations, mild to severe hydrocephalus, skull dysplasia and odontoid dysplasia. White matter alterations were evident as large areas and as multiple dispersed spots of prolonged T1 and T2 value. Reduced gray/white matter contrast was demonstrated on T2-weighted MRI images. It is important to examine the cranio-cervical junction carefully for thickening of dura mater in all patients with mucopolysaccharidosis examined by CT or MRI, because of the generally progressive clinical course of MPS. In patients with symptomatic cord compression, surgical intervention should be considered.

Adolescent↗