Search PubMed⌕ Search

Biomedical subjects

F De Marco

Publications and source records attributed to F De Marco.

At least 55 records · Page 3Linked to original sources
PubMed1983

[Blood amino acids in chronic HBsAg positive liver disease].

Typical changes in blood aminoacid concentrations have been described in patients with severe liver disease. In this study we measured the serum amino acid levels, by Beckman Aminoacid Analyzer, in 11 healthy subjects and 24 HBsAg-positive patients with biopsy-proven liver disease (4 CPH, 10 CAH, 10 cirrhosis). A significant decrease in total aminoacids was observed in CAH and cirrhosis groups (-24% and -22% respectively). The three branched chain aminoacids (BCAA = val + leu + isoleu) were reduced by 24% (P less than 0.002) and 37% (P less than 0.001) in the CAH and cirrhosis groups respectively. Tyrosine was the only of the aromatic aminoacids (AAA) to increase in cirrhotics (+ 34%, P less than 0.02). The molar ratio BCAA/AAA was 3.6 in controls, 3.8 in CPH, 3.1 in CAH (P less than 0.025) and 1.9 in cirrhosis (P less than 0.001). A linear correlation was found between molar ratio BCAA/AAA and serum albumin in all patients (P less than 0.001). These results document the presence of specific quantitative changes in serum aminoacids of HBsAg positive patients, which appear related to severity of liver disease and comparable to the alterations described in non viral chronic liver disease.

Adolescent↗
PubMed1983

Effects of cold acclimation on the feeding pattern and energetic metabolism of genetically obese Zucker rats.

1. The feeding pattern, growth rate and energetic metabolism were studied in obese Zucker rats of 5-12 weeks of age kept at ambient temperatures of 22 or 10 degrees C. 2. During this period, the increment in obesity of the 22 degrees C-exposed animal was found to be due to diurnal hyperphagia and not to a lowered resting metabolism. 3. In the 10 degrees C-exposed rat the development of non-shivering thermogenesis associated with a lack of enhancement of food intake leads to prevent the obesity.

Acclimatization↗
PubMed1982

[Plasma insulin and glucagon during experimental MHV-3 virus hepatitis in mice].

Insulin and glucagon values were determined in the plasma of mice during MHV-3 experimental viral infection. The results showed a different behaviour of the two hormones. The insulin values remained normal until the 12th hour of infection, with a statistically significant increase as from the 12th hour up to their maximum peak at the 24th hour, remaining constant at that level until the 72nd hour. As for the glucagon values there was a statistically significant decrease until the 24th hour of infection when they suddenly began to increase up to their maximum peak at the 48th hour remaining constant at that level until the 72nd hour. Increased of the insulin values may be attributed to liver cell damage because of the decreased metabolization of the hormone. As for glucagon the results of the decreased values during the initial phase of the infection may be the concentration decrease of free plasma amino acids, whereas the increased values during the subsequent phases is probably caused by the concentration increase of free plasma amino acids, of hypogycemia and of stress.

Amino Acids↗
PubMed1982

Effects of propylthiouracil on MHV-3 virus mouse hepatitis.

A study was undertaken to observe the effect of propylthiouracil (PTU) on MHV-3 virus mouse hepatitis. PTU-treatment adversely influenced the course of the hepatitis. This effect was reflected by a significantly higher mortality rate, in spite of the absence of any significant difference of the plasma transaminase activity increase and of the liver virus content.

Alanine Transaminase↗
PubMed1979

Influx of glycyl-proline and free amino acids across intestinal brush border of phenobarbital-treated rats.

In a previous study the authors have shown that treatment with phenobarbital in the rat is followed by a generalized increase of amino acid concentration in the plasma. In order to better clarify this phenomenon, the effect of phenobarbital on intestinal protein absorption was now studied by measuring the influxes of Glycyl-L-Proline, L-Phenylalanine, L-Lysine and L-Glutamic acid across the brush border of jejunum and ileum in rats treated with phenobarbital for two or four days. No significant changes of these influxes were observed in the treated animals as compared to the controls, hence suggesting that the effect of phenobarbital on plasma levels of free amino acids is not mediated by an effect on intestinal absorption. The rate of Glycyl-Proline influx as compared to those of amino acid influxes suggests the occurrence of a carrier-mediated transport process for this dipeptide in the rat intestine as previously shown in the rabbit.

Amino Acids↗
PubMed1978

Pattern and concentration of free amino acids in the plasma and liver tissue of phenobarbital-treated rats.

The pattern and concentration of free amino acids in the plasma and liver tissue of phenobarbital-treated rats was investigated. In phenobarbital-treated rats, there was a significant plasma increase of the total concentration of free amino acids. No significant change in liver free amino acid concentration was observed because of the contemporaneous and general increase in liver size which does not allow observation of any percentual variation in amino acid concentration.

Amino Acids↗
PubMed1977

Free amino acids in plasma during experimental infection of mice with the MHV-3 strain of mouse hepatitis virus.

The concentrations of total free amino acids, single free amino acids, urea, and ammonia were determined in plasma of mice during experimental infection with the MHV-3 strain of mouse hepatitis virus. Analysis of free amino acids was done by ion-exchange resin chromatography under conditions that allowed the use of a single chromatographic column, separation of glutamine and asparagine, and an accelerated rate of chromatography. The results showed that as early as 6 hr after infection there was a decrease in the concentration of several free amino acids as well as in the total concentration of free amino acids in plasma. For most of the amino acids the decrease persisted until 48 hr. Only at 72 hr, during severe cytolysis, did the concentration of amino acids increase significantly. It is suggested that the decrease during the initial phases of the infection may be due to a thermolabile factor that is produced by circulating leukocytes and that effects a flow of free amino acids from the plasma toward the liver. The final increase in concentration of several free amino acids reflects the cytolytic damage to the liver caused by the virus.

Amino Acids↗
PubMedDate not supplied

Susceptibility of human immunodeficiency virus to antiviral agents measured by infectious virus yield reduction.

Under single growth cycle conditions in C8166 lymphoblastoid cells human immunodeficiency virus shows a replication curve which is completed at 24 h post-infection. At lower multiplicity of infection virus yield peaks at approximately 72 h post-infection but in both cases the titer of the virus released in the medium is negligible with respect to that which remains cell-associated. A method based on back-titration of virus in cryolysates of C8166 cells infected with HIV and treated with antiviral compounds has been used to evaluate HIV sensitivity to such agents. Under single growth cycle conditions dose response curves appear linear and permit rapid and accurate determination of the endpoint activity. Under multiple growth cycle conditions the inhibitory activity may be measured during the exponential growth phase, at 48 h post-infection. This method, which directly measures production of infectious virus rather than indirect probes of viral replication such as reverse transcriptase or antigen production, offers the advantage of a precise determination of the degree of activity of antivirals also acting on viral assembly or release.

Antiviral Agents↗