PubMed Health⌕ Search

Biomedical subjects

E Porro

Publications and source records attributed to E Porro.

At least 19 recordsLinked to original sources
PubMed1998

KIF3C and KIF3A form a novel neuronal heteromeric kinesin that associates with membrane vesicles.

We have cloned from rat brain the cDNA encoding an 89,828-Da kinesin-related polypeptide KIF3C that is enriched in brain, retina, and lung. Immunocytochemistry of hippocampal neurons in culture shows that KIF3C is localized to cell bodies, dendrites, and, in lesser amounts, to axons. In subcellular fractionation experiments, KIF3C cofractionates with a distinct population of membrane vesicles. Native KIF3C binds to microtubules in a kinesin-like, nucleotide-dependent manner. KIF3C is most similar to mouse KIF3B and KIF3A, two closely related kinesins that are normally present as a heteromer. In sucrose density gradients, KIF3C sediments at two distinct densities, suggesting that it may be part of two different multimolecular complexes. Immunoprecipitation experiments show that KIF3C is in part associated with KIF3A, but not with KIF3B. Unlike KIF3B, a significant portion of KIF3C is not associated with KIF3A. Consistent with these biochemical properties, the distribution of KIF3C in the CNS has both similarities and differences compared with KIF3A and KIF3B. These results suggest that KIF3C is a vesicle-associated motor that functions both independently and in association with KIF3A.

Amino Acid Sequence↗
PubMed1997

Screening for coeliac disease: the meaning of low titers of anti-gliadin antibodies (AGA) in non-coeliac children.

Coeliac disease is diagnosed by means of jejunal biopsy, an invasive procedure. Anti-gliadin antibodies (AGA) have therefore been used in the first screening of the disease. On the other hand, low titers of AGA are widely detected also in normal subjects. In order to investigate if low levels of AGA could be correlated with laboratory and clinical data, we performed a study on 167 subjects with various illnesses, such as recurrent abdominal pain, failure to thrive, short stature, diarrhoea or constipation, cow-milk protein intolerance and/or food allergy, recurrent vomiting or previous gastroenteritis, all non coeliac conditions which have been associated with AGA presence. Seventy coeliac children, all biopsied, were selected as a control group. Among the 167 cases we found 60 subjects positive for AGA (35.9%), a high proportion as compared with the general population. Only 33/167 patients, all IgG and IgA AGA positive, fulfil our laboratory and clinical criteria to perform a 'confirming' biopsy. For the 134 residual cases (14 IgA, 13 only IgG AGA positive, 107 AGA negative) a diagnosis of coeliac disease has been excluded by clinical criteria (scoring). As a whole, the patients with coeliac disease had significantly higher levels of AGA of both IgG and IgA classes (p < 0.01). On the other hand, no significant difference emerged for all the anamnestic and laboratory parameters considered between AGA+ and AGA- non-coeliac subjects. However, laboratory parameters of IgG-AGA and/or IgA-AGA positive patients were similar to those of coeliac children for ion, Xylose, total IgA count. As no biopsied case showed mucosal atrophy, it is suggested that the presence of even low AGA levels in non-coeliac children may represent a highly sensitive index of intestinal alteration causing an increased permeability to macromolecules, but it is very unlikely that one could detect coeliac children by means of Ig-AGA among such illnesses and normal subjects. Strong clinical diagnosis and laboratory parameters are required to justify intestinal biopsies. In fact, the production of AGA seems to be a merely immunological phenomenon linked to an increased and probably transient permeability to macromolecules of the intestinal mucosa.

Adolescent↗
PubMed1993

Early wheezing and breast feeding.

There is uncertainty as to whether breast feeding protects against subsequent illnesses; it has been suggested that breast feeding may have some protective effects on the severity of long-term outcome of bronchiolitis and in reducing morbidity. We have assessed the effects of breast feeding in 266 patients and 199 controls, all patients were early wheezers (i.e., under 2 years old). Between these groups we found differences in socioeconomic, environmental, and atopic conditions, but there were no significant differences in the numbers who had been breastfed. However, within the group who had had early wheezing we found that infants who had been breastfed for at least one month subsequently had less severe wheezing. These results suggest that breast feeding may be a protective factor for early wheezing only during the first month of life, and a delaying factor in the following months.

Breast Feeding↗
PubMed1992

Atopy and environmental factors in upper respiratory infections: an epidemiological survey on 2304 school children.

Upper respiratory infections (URI) during the first years of life are mostly viral in origin. However, a number of observations suggest the influence of both predisposing and triggering factors. Atopy in particular seems to play an important role as do environmental factors. Many children with early symptoms such as blocked or runny nose are likely to become skin-positive later in life to antigens such as, e.g., D. pteronissinus. A standardized questionnaire was administered to 2304 schoolchildren in order to ascertain the URI frequency and to correlate it with family and environmental factors and with results of prick tests for main allergens in our climate (D. pteronissinus and Grasses). Results showed a wide overlapping of URI and lower respiratory illnesses (in particular, asthma), which are widely distributed in the families of patients. Passive smoking and the quality of housing are the main triggering environmental factors. In our sample, skin positivity for D. pteronissinus and Grasses largely exceeds the symptomatic portion of the whole population. It is therefore suggested that many asymptomatic children are "at risk" for allergic respiratory illness. The highest incidence of winter rhinitis in skin-negative subjects (71.7%) and the skin positivity for D. pteronissinus in patients with perennial symptoms, suggest the importance of both atopy and viral infections in the occurrence of URI. Nasal troubles are most frequent in asthmatic subjects and may be considered the actual additional symptom in asthma.

Adolescent↗
PubMed1992

Bronchiolitis in the history of the asthmatic child.

In a retrospective analysis of the history of 1,700 asthmatic children, 167 (9.8%) were found to have had bronchiolitis during the first 2 years of life. These 167 cases with asthma and bronchiolitis were matched against 215 selected cases of asthma without bronchiolitis. Both groups attended our Ambulatory Care Unit for Asthma. Data were collected from the clinical cards of the children. Asthmatics who had bronchiolitis were found to have an earlier onset of asthma (p less than 0.001), earlier resolution of symptoms (p less than 0.05 total; p less than 0.01 females), and less evidence of atopy (p less than 0.005). It is suggested therefore that the bronchial hyperreactivity in asthma following bronchiolitis may have different underlying mechanisms than in the typical atopic case, without preceding bronchiolitis. Long-term follow-up studies in infants with bronchiolitis are still necessary in order to clarify the process by which bronchiolitis predisposes to bronchial hyperreactivity and asthma. The consequences of the viral infection itself may lead to pathophysiological processes that promote bronchial hyperreactivity. On the contrary, an underlying condition of bronchial hyperreactivity could be the "primum movens" of the bronchiolitis itself.

Asthma↗
PubMed1989

Evaluating bronchial hyperreactivity tests in epidemiology.

The aim of this study is to assess the value of the most common tests which can be used in epidemiological surveys to identify asthmatic children. We reviewed anamnestic information from a self-administered questionnaire, bronchial reactivity by means of exercise-test, bronchodilation-test with trimethochinol, carbachol-test (PD20 FEV1 was reported), cutaneous reactivity monitored by prick-test. (Data from a polycentric epidemiological study). We conclude that, while these tests are very useful in the initial study and in the further follow-up of the asthmatic child, providing also information about the possibilities of management of bronchoconstriction and its pharmacologic prevention, they show a limited value in the absolute diagnosis of asthma.

Air Pollutants↗
PubMed1987

First trimester studies of a fetus at risk for triose phosphate isomerase deficiency.

A first trimester prenatal diagnosis was offered to a mother whose child had died of haemolytic anaemia and multisystem disease caused by TPI deficiency. The deficiency state was characterized by greatly reduced TPI activity in both erythrocytes and peripheral lymphocytes. Specific activity of TPI in trophoblast homogenates from the index fetus was about 30 per cent less than in the controls, but the heat stability test showed overlap. These data were confirmed in uncultured and cultured amniotic cells, where glycolytic intermediate concentrations DHAP, GAP and FDP fell in the range of controls. These results suggested that the fetus was a TPI heterozygote. This prenatal prediction was confirmed by RBC and haematological studies at birth.

Amniocentesis↗
PubMed1986

The fetal pathology of the XXXXY-syndrome.

A second case of fetal XXXXY-syndrome detected by prenatal chromosome analysis is presented. The pathological findings include a facial aspect featuring fetal Down's syndrome, hypogenitalism and hypogonadism with excessive reduction of germ cells and also skeletal abnormalities that may be interpreted as early changes, preceding phalangeal shortening V and radioulnar synostosis.

Adult↗
PubMed1983

Prenatal diagnosis, fetal pathology and cytogenetic analysis of a 46,XX/47,XX, + 15 mosaic.

Mosaic trisomy 15 was prenatally diagnosed on amniotic fluid cells from two consecutive amniocenteses and was confirmed on cells from five different fetal tissues. The proportion of normal versus trisomic cells was consistently higher in the amniotic cell cultures and--with one exception--in the fetal tissues, while serial subcultures gave different results. The slightly atypical external features and internal malformations of the affected fetus as compared to the only clinical observation from the literature are not unusual enough to allow the delineation of a specific malformation pattern.

Abortion, Therapeutic↗
PubMed1976

"Jumping" satellites in three generations: a warning for paternity tests and prenatal diagnosis.

Prominent intensely fluorescent satellites on one chromosome 22 seem to have been transferred, during gametogenesis of a male carrier of a balanced 10/22 translocation, from the normal 22 to the translocated 22 in his daughter and son, both carriers of the translocation. Prenatal diagnosis was performed in the carrier daughter and in the chromosomally normal female foetus the satellites have jumped back to one normal chromosome 22. The phenomenon is probably due to exchanges between the short arms of chromosome 22 at meiotic pairing in the father and in his daughter. These observations give a warning for caution in the use of marker variants for paternity tests and prenatal diagnosis.

Amniocentesis↗
PubMedDate not supplied

Comparative study of 15 lysosomal enzymes in chorionic villi and cultured amniotic fluid cells. Early prenatal diagnosis in seven pregnancies at risk for lysosomal storage diseases.

A large number of chorionic villi samples obtained from women undergoing elective first trimester termination of pregnancy was analysed by enzyme assays similar to those applied to cultured amniotic cells. The levels of 15 lysosomal enzymes were compared to those observed in tissue cultures of amniotic cells obtained through amniocentesis at 16-18 weeks of pregnancy and the results were discussed in order to assess the usefulness of trophoblast biopsy for first trimester diagnosis of hereditary lysosomal diseases. The data suggest the applicability of this source of fetal cells for prenatal diagnosis of fifteen respective genetically determined enzyme deficiencies with the probable exception of alpha-L-iduronidase deficiency. Enzyme determinations were performed on chorionic villi samples of two pregnancies at risk for Tay-Sachs disease, three pregnancies for GM1 gangliosidosis type 1, one for mucopolysaccharidosis type VI and one for Wolman's disease.

Amniocentesis↗
PubMedDate not supplied

Overhead electricity power lines and childhood leukemia: a registry-based, case-control study.

AIMS AND BACKGROUND: To evaluate the role of exposure to low-frequency electromagnetic fields generated by overhead power lines on the risk of childhood leukemia, we carried out a case-control study in the area (Varese province) covered by the Lombardy Cancer Registry. METHODS AND STUDY DESIGN: Exposure to magnetic fields was estimated using line load data and the distance between subjects' homes and the nearest power line. A total of 101 cases and 412 controls were investigated. RESULTS: Twenty subjects (9 cases and 11 controls) were considered exposed. A significant fourfold increase in risk for leukemia in exposed subjects and a dose-response relationship were found. The risk was higher than that reported by other studies. Potential biases related to the representativity of controls and validity of exposure assessment do not seem to have influenced the risk estimates. CONCLUSIONS: We suggest that measures to remedy residential exposure should be taken wherever practicable.

Adolescent↗