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Biomedical subjects

G Riva

Publications and source records attributed to G Riva.

At least 73 records · Page 4Linked to original sources
PubMed1996

Growth, growth hormone and cognitive functions.

The interactions among short stature, growth hormone (GH) and cognitive functions have been extensively studied so far. However, although it seems well established that short stature is associated with cognitive problems, little effort has been made to point out the presence of specific psychological effects related to the different forms of short stature. In 'short normal' children, the presence of a scholastic underachievement seems to suggest that short stature 'itself' might predispose these patients to some of their psychosocial difficulties. The higher incidence of academic failure, in presence of a normal intellectual functioning, has been attributed to environmental and psychosocial factors, including over-protective parents and low self-esteem resulting from the impact of short stature. These problems appear to be common also to other forms of short stature (such as Turner's syndrome) where, however, they are frequently associated with other specific deficits. The in vivo model which might allow, at least in part, better understanding of GH (per se)-dependent effects is represented by GH deficiency (GHD), in which, however, the specific role of GH on psychological functioning is frequently masked by the presence of associated hormonal deficiencies. Children with isolated GHD are reported to have specific educational deficits, in particular learning disability and attention-deficit disorders, which have been tentatively attributed to a compromised intellectual potential. The psychological effects of long-term GH treatment in children with GHD still remain controversial, with some retrospective studies describing a generally beneficial outcome. Since early experiences in school are closely related to success in adult life, the possible implications that GHD during childhood holds during adulthood have been recently considered. Although regional differences have been observed in subgroups of adults with GHD, it seems that these patients have normal cognitive functions and educational attainment, but are more likely to be unemployed (and unmarried) than members of the general population. In general, patients with GHD, who have been treated at centers where psychological counselling was an integral part of the treatment program, seem to be better adjusted in adult life. For these reasons, a multidisciplinary treatment approach could allow early detection of problems in academic achievement and psychosocial development in patients with short stature, being immediately able to provide the appropriate educational and counselling interventions.

Adult↗
PubMed1996

The role of emotional and socio-cognitive patterns in obesity: eating attitudes in obese adolescents before and after a dietary-behavioural therapy.

The aim was to examine attitudes towards eating in a group of obese and nonobese female adolescents (N = 200), in particular whether obese subjects have characteristic attitudinal patterns associated with obesity. Analysis concluded that our sample, both overweight and normal subjects, share the negative stereotypic attitudes towards obese persons. However, there was a considerable difference in emotional evaluation of eating behaviour. If normal subjects attribute a strong negative emotional connotation, obese subjects not only did not recognise the "abnormality" of overeating, but preferred it. This can be explained by the presence of an association of strength and power with overeating: at the moment of eating, obese subjects feel themselves "strong" and even "superior," thereby compensating for their rather weak and fragile personalities. The emotional evaluation of eating behavior did not change after a 10-week dietary/behavioural treatment.

Adolescent↗
PubMed1996

Innovative materials: the NiTi alloys in orthodontics.

Since ten years the NiTi alloys have gained an ever increasing place in orthodontic practice: that is due to their peculiar mechanical properties ascribed to a martensitic thermoelastic transformation which can be thermally or, in a proper temperature range, stress-induced. In the last case, when martensite is stress-induced at body temperature, the stress-strain behaviour is pseudoelastic with large deformations gained or recovered at constant stress, respectively in direct/reverse transformation: this behaviour exploited in orthodontics allowed to overcome the drawbacks intrinsic to the use of conventional alloys as stainless steel or Co-Mo alloys, where small displacements can be achieved at decreasing loads. From the phase state diagram of NiTi alloys it appears that at body temperature they are stable, but out of equilibrium: thermal treatments at intermediate temperatures can therefore modify the equilibrium state and as a consequence the transformation temperatures respect to body temperature. That allows to modify the recovery stress level according to the requirements of practice and thus disclosing new roads: the capability to foresee NiTi archwires pre-programmed in different sections, with a personalized scheme. Attention has not currently been paid to the modifications in the recovery stress induced by a temperature change inside the oral cavity. Recent results have shown that the thermal changes in the oral cavity induced by cold/hot liquid intake can considerably modify the stress level to which the dentition is exposed: though confined to the time extent connected with drinking, similar effects can be expected also for meals intake and should be taken into account for a correct procedure.

Biocompatible Materials↗
PubMed1995

Growth hormone treatment in adults with childhood onset growth hormone deficiency: effects on psychological capabilities.

The psychological aspects (personal traits, way of relating to the surrounding environment, perception of body image, degree of self-esteem) of eight adults with childhood onset growth hormone (GH) deficiency (GHD) were studied before and after 6 months of recombinant GH therapy. Each subject was evaluated using the following tests: the Bem Sex Role test, the non-verbal scales of the WAIS test for adults, the State-Trait Anxiety Inventory, the Experiential-World Inventory, the Image-Marking Method and the Draw-a-Person test; a psychoneurophysiological profile was also evaluated in order to monitor, by means of four neurophysiological variables (muscular tension, galvanic resistance, skin temperature and heart rate), the reactions to specific and aspecific stress. Before treatment, adults with GHD tended to underestimate their body size by an average of 30%, with peaks of 47% for the head area; furthermore, they showed a low level of self-esteem, a closed attitude towards social relationships, a pessimistic attitude with a tendency towards depression and a strong sense of detachment from the outside world. After 6 months of GH treatment, patients presented an overall improvement in relation to intellectual tasks, accompanied by a lower level of stress during their performance. A clear improvement was also observed in terms of emotional control during specific and aspecific stress, which might contribute a positive effect on their interrelationships. As expected, the treatment was not able to reduce the subjects' highly distorted perception of body image, due to the fact that GH treatment, despite a clear amelioration of lean/fat body mass ratio, did not change their body proportions.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1995

Body image and social attitude in growth-hormone-deficient adults.

This study was done to evaluate the perception of body image and psychosocial attitudes in a sample of 8 male adult subjects with growth-hormone deficit before and after six months of therapy. Before treatment the subjects tended to underestimate body size and were characterized by low self-esteem, a closed attitude towards social relationships, a pessimistic attitude with a tendency towards depression, and a strong sense of detachment from the outside world. After the treatment, even if the subjects continued to underestimate body size, we observed an improvement in terms of emotional control and well-being, accompanied by lower scores on anxiety. An integration of a psychological support in the GH therapy could help the patients to overcome problems of bodily and social acceptance.

Adult↗
PubMed1995

Self-others perception in a clinical sample of obese women.

The purpose of this research, using correspondence analysis on responses to semantic differential scores, was both to examine self-perception in a clinical sample of 120 obese women and to compare this with their attitudes toward obese, thin, and normal persons. Analyses allow us to conclude that, if obese women, as reported previously, consider obesity as a largely negative condition, they have an ambivalent attitude towards themselves. Even though they share the negative connotations socially attributed to obesity, emotionally these obese women not only tend not to recognize their "abnormality" but strongly desire it.

Adult↗
PubMed1995

[Alexithymia and psychopathology in a clinical sample of obese subjects].

The study examines the relationship between obesity and alexithymia, focusing on relations with the level of psychopathology. The Toronto Alexithymia Scale (TAS) was performed in 200 women (100 obese subjects and 100 normal weight individuals). In obese subjects TAS was accompanied by a series of tests including the Minnesota Multiphasic Personality Inventory (MMPI), Ipat Anxiety Scale (ASQ) and the Eating Attitude Test (EAT). The results obtained show that from a psychopathological point of view obesity cannot be considered a single phenomenon, and that it is possible to identify at least 3 groups with different psychopathological phenomenon as a whole, but it appears to be present, in association with other psychological traits, only on the subgroup (35% of the total) of subjects with borderline personalities.

Adult↗
PubMed1990

Specific binding of endothelin on human bronchial smooth muscle cells in culture and secretion of endothelin-like material from bronchial epithelial cells.

Endothelin, synthesized by endothelial cells, is the most potent vasoconstrictor and bronchoconstrictor agent known. We investigated endothelin release from human bronchial epithelial cells and the binding of the peptide to autologous bronchial smooth muscle cells in culture. Epithelial and smooth muscle cells were isolated by enzymatic digestion of bronchial tissue obtained on surgery, and cultured to confluency by standard methods. Epithelial cells stained positively for cytokeratin filaments. Smooth muscle cells stained uniformly for alpha-smooth muscle actin. Immunoreactive endothelin contents in the supernatants of epithelial cells extracted on C8 Amprep columns were evaluated by radioimmunoassay. Epithelial cells released appreciable amounts of immunoreactive endothelin into the culture medium (from 0.65 to 2.1 pmol/ml). A single specific binding site for [125I]endothelin 1 was identified on bronchial smooth muscle cells with an apparent Kd of 113 pM and a maximal binding capacity of 22.1 fmol/10(6) cells. At room temperature the binding was saturable, reached equilibrium at 120 min (25 pM endothelin 1), and was slowly and incompletely reversed by unlabeled endothelin over a period of 8 h. Conditioned medium from epithelial cells inhibited the [125I]endothelin 1 binding, dose dependently, and the effect was antagonized by monospecific antiserum. Thus, human bronchial smooth muscle cells possess specific binding sites for endothelin 1 and human bronchial epithelial cells secrete an endothelin-like material. This may have a role in the pathogenesis of asthma.

Binding Sites↗
PubMed1988

Analysis of allergenic components of a Parietaria judaica pollen extract by chromatographic methods for the evaluation of purification procedures.

Size-exclusion and ion-exchange high-performance liquid chromatography were used to monitor the presence of polymeric aggregates and of families of allergens of similar isoelectric point in Parietaria judaica pollen extracts. A radio-allergo-sorbent test and chromatofocusing were used for the analysis of individual fractions. This allows the detection of two groups of allergens, having pI of 4.7 and greater than 5.7, respectively, and shows the effect of dialysis or ultrafiltration on the distribution of allergens.

Allergens↗
PubMed1988

IgE and IgG antibodies in Toxocara canis infection. A clinical evaluation.

The relationship between IgE and IgG antibodies against the metabolic exoantigen of Toxocara canis (TEX antigen) in sera of selected patients with the ocular and visceral form of the disease have been investigated. The specificity and sensitivity of the TEX antigen employed in immunoenzymatic and radioimmunologic assays have been verified. Six hundred and forty-one sera from healthy donors were tested as controls. Our data emphasize the importance of IgE antibodies to ocular larva migrans syndrome and suggest that they play a significant role as a marker of infection. In the visceral form, IgG antibodies seem to mask the presence of IgE by a competitive mechanism toward the same epitopes of the parasite. In fact, IgE antibody titers increase after depletion of IgG from serum.

Antibodies, Helminth↗
PubMed1987

Long term results (15-30 years) of surgical repair of aortic coarctation.

The late outcome in 226 patients who survived surgical repair of aortic coarctation was assessed 15-30 years after operation. Twenty six patients died during the follow up mainly from causes related to surgical repair or to associated cardiovascular anomalies. The survival rates of patients operated on between the ages of four and 20 years are 97%, 97%, 92% at 10, 20, and 30 years after operation. For patients operated on after the age of 20 the corresponding rates are 93%, 85%, and 68%. This difference is statistically significant from the fifteenth year of follow up onwards. The survival of patients operated on before the age of 20 is not significantly different from that of a comparable general Italian population. Recoarctation occurred in only 8% of patients who had end to end anastomosis, whereas it occurred in 35% of those who had other types of operation. Two thirds of the patients were hypertensive at the last visit. The actuarial curve shows that blood pressure was normal in most patients 5-10 years after operation, but 30 years after coarctation repair only 32% of patients are expected to be normotensive. Thus early repair of aortic coarctation appears to improve long term survival. Intervention in older patients and when blood pressure is high seem to be the most important predictors of late hypertension.

Adolescent↗
PubMed1987

RAST and ELISA in three autochthonous parasitic infections in Italy: toxocariasis, hydatidosis and fascioliasis.

Toxocariasis, Hydatidosis and Fascioliasis are common autochthonous parasitic infections in Italy. RAST and ELISA have been evaluated for serological diagnosis. Eight sera from Toxocariasis, fifty from Hydatidosis and two from Fascioliasis have been examined. Excretory/secretory antigen has been employed for the serology of Toxocariasis, hydatic fluid for Hydatidosis and embryonated-eggs antigen for Fascioliasis. The RAST resulted positive in 4/5 cases of the visceral form of Toxocariasis and 3/3 in the ocular form, in 2/2 cases of Fascioliasis and 27/50 of Hydatidosis. The ELISA resulted positive respectively in 5/5, 3/3, 2/2, and 19/50 cases. The sensitivity and specificity of the tests employed have been proved.

Animals↗
PubMed1985

Short and long-term clinical effects of plasma-exchange in 33 cases of myasthenia gravis.

The authors examine the results of plasma exchange (PE) treatment in 33 patients with myasthenia gravis, who underwent a total of 49 cycles of treatment. On the basis of clinical response, evaluated in relation to a modification of the functional state and to the duration of improvement after PE, we selected a group of 20 responsive patients ("responders" = 60.6%) and 13 non-responsive patients ("non-responders" = 39.4%). Positive effects, some only short-lasting, were observed in 24 patients (72.7%) after 32 cycles of a total of 49 cycles (65.3%). Out of the 11 most critical patients, 7 (63.6%) were considered responders, given the importance and duration of the improvement they presented, while 2 other patients had clear but short-lasting improvements; in these 9 patients, the positive effects amounted to 81.2%. Factors presumably responsible for therapeutic failure in the non-responders are discussed.

Adolescent↗
PubMed1982

[Behavior of high-density lipoproteins in drug lipid-lowering treatment].

Changes in serum lipids, the individual lipoprotein fractions after ultracentrifugation and the apoproteins B, A1 and A2 were studied in 66 patients with primary hypercholesterolemia under treatment with different lipid-lowering agents. After 3 months with dietary treatment alone and a 4-week placebo period the patients were given bezafibrate (3 X 200 mg daily), colestipol (2 X 10 g per day) or probucol (2 X 500 mg daily) for 12 months, followed by another 4-week placebo period at the end of the study. Colestipol showed the best lipid-lowering effect (total and LDL cholesterol were decreased by 20% and 23% respectively) but satisfactory total and LDL cholesterol lowering results were also obtained with the other substances. However, the changes in HDL differed widely among the three substances: bezafibrate increased HDL cholesterol and the HDL apoproteins A1 and A2 significantly, colestipol did not alter these parameters, while probucol treatment was followed by a significant decrease in both HDL-cholesterol and the apoproteins A1 and A2.

Adult↗
PubMed1982

Peptichemio induction therapy in myelomatosis.

Fifteen patients with multiple myeloma, two of whom had plasma cell leukemia, were treated between May 1974 and December 1978. Peptichemio was administered intravenously at doses of 40-80 mg/48 h, courses including 4-17 administrations in association with moderate doses of prednisone (15-50 mg/day) and androstanes at high dosages (250 mg weekly). In two patients PTC was associated with vincristine (VCR) administered on the first day of the course. Eight patients were previously untreated, four had been resistant to melphalan (MPH) and/or cyclophosphamide (CTX), and three had been treated irregularly with one or both of these alkylating agents. The criteria of response to therapy are reported. Out of a total of 15 PTC courses administered we obtained 13 responses, eight complete and five partial; no response was achieved in the other two patients. In the four patients who were resistant to MPH and/or CTX we obtained three responses, which were maintained with the same alkylating agent to which they had been resistant previously. The time needed to obtain a response in 90% of the patients was 6 weeks. Peptichemio was shown to be effective in patients in an advanced stage of the disease, in patients with light-chain myeloma and in those with plasma cell leukemia. The association of VCR potentiated the antitumor effect, but also increased the myelotoxicity. The PTC treatment was well tolerated. It is suggested that PTC be used in induction treatment of myelomatosis and in patients resistant to traditional alkylating agents.

Adult↗