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S Adam

Publications and source records attributed to S Adam.

104 records · Page 6Linked to original sources
PubMed1982

Radiolysis of alpha, alpha-trehalose in concentrated aqueous solution; the effect of co-irradiated proteins and lipids.

gamma-Radiolysis (dose-rate: 0 X 89 Gy/s) or electron (e)-radiolysis (dose-rate: 5 X 10(7) Gy/s) of unbuffered aqueous solutions of alpha, alpha-trehalose (concentration: 60 mg/ml, radiation dose: 20 kGy) at 0 degree C yielded glucose (Ggamma = 1 X 7; Ge = 0 X 63) and 5-deoxyxylohexodialdose (Ggamma = 0 X 21; Ge = 0 X 05). Buffering at pH-values of 5 X 0 or 5 X 5 and irradiation caused increased formation of these monomeric products, particularly of the deoxy-compound. On addition of increasing amounts of bovine serum albumin or ovalbumin (10-30 mg/ml) and irradiation the yields of products were markedly reduced. The decrease in glucose formation was less pronounced when sperm whale myoglobin was present during gamma- or electron-irradiation. The G-values of 5-deoxyxylohexodialdose, however, were increased by 45 per cent (gamma-irradiation) and 70 per cent (electron-irradiation) at approximately 10 mg/ml of admixed myoglobin. Further increase in myoglobin concentration led to a gradual decrease in the yields of the deoxy-product. The observed effects are explained by scavenging of water radicals and by interactions of the added substrates with sugar radicals. Emulsified lipids (palmitic acid methylester or trilinoleic glycerol) did not affect the radiation-induced formation of products from trehalose.

Deoxy Sugars↗
PubMed1978

Deaths under 50.

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Attitude to Health↗
PubMed1977

gamma-radiolysis of N2O-saturated aqueous solutions of trehalose and trehalose/amino acid mixtures.

gamma-radiolysis of aqueous N2O-saturated solutions of alpha, alpha-trehalose (10(-2) M) with doses of 500 krad yielded glucose (G = 2.3), gluconic acid lactone (G = 0.25) and--after reduction--iditol (G = 0.15), mannitol (G = 0.05), 5-deoxy-glucitol (G = 0.34) and 2-deoxy-glucitol (G = 0.14). The decomposition of trehalose (G = -5.9) was reduced, if equimolar amounts of amino acids (alanine, leucine, phenylalanine, methionine or cysteine) were present during irradiation. The extent of this reduction has been correlated with the .OH radical-scavenging properties of the added amino acids. Cysteine also protected trehalose by the repair of initially formed trehalose radicals and almost completely suppressed the formation of products. The addition of the remaining amino acids led to an increase of molar product yields (glucose, 5-deoxy-glucitol and 2-deoxy-glucitol), which was related to the decomposition of trehalose. This finding was explained by hydrogen transfer from the amino acids to precursor radicals of the products.

Amino Acids↗
PubMedDate not supplied

Study of the malformation of ductal plate of the liver in Meckel syndrome and review of other syndromes presenting with this anomaly.

Meckel syndrome (MIM 249.000) is an autosomal recessive disorder with a variable spectrum of anomalies. Since the first reports of this syndrome, very broad diagnostic criteria have been proposed, but the process of defining them continues. It is probable that at least two of three manifestations, including cystic kidney dysplasia, occipital encephalocele or other anomaly of the central nervous system, and postaxial polydactyly occur in most cases. Arrest of the development of intrahepatic bile ducts at the stage of the bilaminar plate formation or ductal plate malformation is considered of high diagnostic value in Meckel syndrome, but there is no complete agreement in the literature about its occurrence. The aims of this investigation were to study the prevalence and morphologic patterns of ductal plate malformation of the liver in Meckel syndrome by evaluating the dilatation of primitive biliary structures and the increase in connective tissue of the portal tract. Archival data files from four German centers (Berlin, Freiburg, Heidelberg, Mainz) were reviewed. Liver sections of 30 well-studied fetuses with Meckel syndrome were immunostained with antibodies against cytokeratins (intermediate filaments of the cytoskeleton) and factor VIII (an endothelial cell marker) and were evaluated both qualitatively and quantitatively. Cystic kidney dysplasia, occipital encephalocele, and postaxial polydactyly were found in 100%, 90%, and 83.3% of the fetuses, respectively. Ductal plate malformation of the liver was a constant anomaly in Meckel syndrome, seen as frequently as renal lesions. We observed essentially two kinds of hepatic lesions: 23 cases showed mainly a cystic dilatation of primitive biliary structures with little portal fibrosis, while 7 cases showed mainly rings of interrupted curved lumina around a central fibrovascular axis and pronounced portal fibrosis. In these seven cases an abnormal pattern of the portal vein, with many small and closely spaced branches of the portal vein (the so-called pollard willow pattern), was also seen. With respect to other fetal developmental anomalies, no difference between the two types of lesions was found. We also provide a potentially useful comprehensive review of other genetic syndromes in which ductal plate malformations may occur.

Abnormalities, Multiple↗
PubMedDate not supplied

[Evaluation of typical psychopathic traits with juvenile offenders].

UNLABELLED: The concept of psychopathy has received many definitions for the first days of psychiatry. Recently, the Hare's Psychopathy Check List Revised has been created. This scale has the advantage to investigate the classically characteristic traits of the syndrome (need of stimulation, lack of culpability, superficial activity, lack of empathy, impassivity) and to point out the early development of behavior disturbances. In the American classification (DSM IV), oppositional and aggressive behavior in child and adolescent is grouped under the Conduct Disorder diagnostic criteria. This trouble appears to be a strong predictive factor of psychopathy in adult. Identifying the high risk factors of evolution to psychopathic personality would allow an earlier intervention and prevention by multisystemic interventions for example. The present study aims to evaluate in what measure characteristic traits of psychopathy in adults are present in severe juvenile offenders and to point out, in a second time, the differences between adolescents meeting the DSM IV criteria for Conduct Disorder and a control population by a dimensional personality inventory. METHOD: The sample consists in 47 severe juvenile offenders referred for at least 3 months by a Youth Court to a Public Institution for Youth Protection (Belgium, Wauthier-Braine, 1999-2001), who have given an oral contentment and completely fulfilled the Temperament and Character Inventory-TCI. We have collected data about: schooling year by year, number of fails, changes of school; antecedents of oppositional defiant disorder with provocation (ODD, DSM IV criteria); antecedent of Conduct Disorder (CD, DSM IV criteria); penal antecedents (Youth Judge, works of general interest, placements); medico-psychological antecedents (consultation to a psychologist or a psychiatrist, hospitalization, illness, surgical intervention); psychoactive drug use or abuse. We used the TCI--Temperament and Character Inventory. This is a dimensional personality inventory. Based on biological, genetic and clinical hypothesis, it describes 2 types of variables defining personality: Variables of temperament (genetically transmitted and biologically controlled), and Variables of character (learned part of the personality reflecting the degree of adaptation and maturity, varying with environment through development). We have chosen this tool because of its dimensional aspect. Adolescence being a time of psychological and personality changes, such a tool is more useful than a categorical one. We also used this tool to verify the existence of the specific triad described by Cloninger and Svrakic. According to these authors, psychopathic personality in adult is characterized by a specific triad in which novelty seeking is high while harm avoidance and reward dependence are low. These observations are highly correlated to Hare's definition of psychopathy. We give the principal scores for the 7 personality dimensions expressed in global scores (total of the items for each dimension) and pondered ones (global scores divided by the number of items of the dimension x 100). RESULTS: Statistical analysis was performed with the Stateview 5.0 t-test program for data analysis. Statistical results show the absence of a statistically significant difference between the 2 groups for TCI 1, 4.5 and 7 but a statistically significant difference for TCI 2, 3 and 6 (p <.0001). DISCUSSION: The first limitation of our study is linked to the sample composed of young adolescents placed in an Institution for Youth Protection who doesn't reflect the whole population of offenders. A second limitation is correlated to the randomization system: randomization for age but not for sex, ethnical and cultural origin and socioeconomic status. Our results with adolescent offenders don't completely meet the Cloninger's psychopathy triad in adults. Moreover, in literature data, aggressive behavior is correlated to high novelty seeking and associated with low harm avoidance, reward dependence and persistence in children, these items are predictive of antisocial behavior in teenage and young adulthood. In our sample where antisocial behaviors are severe, we should be expecting a high novelty seeking but that is not the case. Our results should be explained by the fact that adolescence in itself is a more powerful factor of high novelty seeking than psychopathic trait. Harm avoidance and reward dependence seem to be a real problem in offending population and reflect aggressive behaviors in adolescents (lack of harm perception, sensitivity and empathy). Another interesting element is the cooperation factor that is significantly lower in the study group. This seems to comfort the hypothesis of a lower social maturity in institutionalized adolescents. CONCLUSION: Regarding to a control group subjects from 15 to 25 years old, adolescent offenders observed in an Institution for Youth Protection show a significantly different profile in the TCI for Harm Avoidance, Reward Dependence and Cooperation. Regarding to adult psychopaths, adolescent offenders partially meet the classical diagnostic triad of psychopathy, what should be indicating that such adolescents already show emotional perturbations: lower harm avoidance, reward dependence and cooperation than control population. This third factor is not characteristic of psychopathy but reflects relational difficulties, which are important in adolescent offenders. So, our study point out the complex psychopathology of adolescent offenders and the coexistence in such adolescents of attachment disorder and the difficulty to treat them because of their multiple lacks (cognitive, psychopathological, familial and scholar). We think important to discuss the necessity of approaches based on the development of personal creative abilities and involving all the professionals concerned in the young's universe. Future researches should compare adolescent offenders and controls randomized for age, sex, socioeconomic, ethnical and cultural status. They also should test specifically the diagnostic triad of psychopathology developed by Cloninger, especially the novelty seeking dimension. Moreover, it would be interesting to integrate these results in a wider protocol and to compare them with clinical, forensic and neurocognitive data, individually and within the familial context.

Adolescent↗