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S Bahrami

Publications and source records attributed to S Bahrami.

At least 73 records · Page 4Linked to original sources
PubMed1987

A preparative high performance liquid chromatography method for separation of lecithin: comparison to thin-layer chromatography.

We have developed a high performance liquid chromatography (HPLC) method to separate lecithin from other phospholipid classes and to obtain lecithin from biologic materials. The separation was performed on a preparative 10-micron Spherisorb column with an optimized solvent system consisting of the following components: acetonitrile, isopropanol, methanol, water, and trifluoroacetic acid. The advantages of this method are the use of an isocratic solvent system limited to about 30 min and the very good separation of the phosphatidyl-choline fraction from the sphingomyelin fraction. Furthermore, the HPLC method has a better recovery rate than the thin-layer chromatography method, and it can be run under automatic control.

Animals↗
PubMed1984

[Influence of parenteral nutrition on phospholipid metabolism in the rat lung in the posttraumatic period].

Most experimental studies in the field of parenteral nutrition following trauma are aimed at a reduction of catabolism and therefore an improvement of the N-balance. The aim of this study was to investigate the influence of PN on PHL composition in the posttraumatic lung, especially in the surfactant fraction. We compared a carbohydrate - amino acid formula with a formula containing carbohydrate - amino acid - lipid. Polytrauma was performed by single femur fracture plus laparotomy with eventeration of the intestines for 30 minutes and hypovolemia (2 ml/100 g bw). After an adaption phase with reduced caloric supply, full caloric support was given from the 4th to the 14th day (100 Kcal/kg bw/day). The following metabolic parameters were used: N-balance; phospholipid total, -classes, -molecular species and fatty acid pattern of lecithin in lung tissue and lavage (using special HPLC and GC techniques). There were small differences between the groups using standard metabolic parameters (such as nitrogen balance). In contrast, we found significantly altered phospholipid patterns in the lung. With lipid emulsion there was an increased fraction of saturated lecithins (mainly dipalmitoyl phosphatidylcholine). From our data we conclude that it is possible to influence surfactant phospholipid composition by parenteral nutrition through the use of lipid emulsion. This might be useful for posttraumatic lung treatment.

Animals↗
PubMed1978

Isolation and characterization of a defective measles virus from brain biopsies of three patients in Iran with subacute sclerosing panencephalitis.

Three cytopathic strains of subacute sclerosing panencephalitis (SSPE) virus were isolated from brain biopsies of three patients. These strains were isolated and maintained by cocultivation of infected brain cells with fresh Vero cells. The biological characteristics of two strains were studied. It was found that these strains remain cell-associated after repeated cocultivations with Vero cells and produce plaques under fluid medium or tragacanth overlay. The correlation with measles virus was demonstrated by the plaque reduction test as well as by the immunofluorescence test. Large numbers of nucleocapsids were observed in the cytoplasm of infected cells but none in nuclei. Intracerebral inoculation of monkeys, adult guinea pigs, newborn and adult hamsters or mice was followed by acute encephalitis and death.

Adolescent↗
PubMed1974

Experimental study of a further attenuated live measles vaccine of the Sugiyama strain in Iran.

After encouraging results of the mass vaccination programme in Iran, in which 5 million children in rural areas were vaccinated with the Japanese Sugiyama strain at its 82nd passage in baby calf kidney, and a progressive decrease in the incidence of measles as well as a reduction of excessive infant mortality, a further attenuated vaccine, produced with the same strain, cloned in Japan, was compared in a field trial with the parent vaccine. The new strain caused fewer reactions than the original strain. Seroconversion with a geometric mean antibody titre of 6.1 was observed in 95% of susceptible children.

Animals↗
PubMed1970

A comparative study of two live measles vaccines in Iran.

The results of immunization of 523 children from 9 months to over 5 years of age with two attenuated measles vaccines, ;Denken' and ;Biken', are described. The clinical reactions following vaccination with both vaccines were mild, but Denken vaccine produced more rashes than the Biken vaccine. The serological conversion was satisfactory for both vaccines but a higher titre of neutralizing and haemagglutination-inhibiting antibodies was found in children immunized with Denken vaccine. The incidence of severe reactions or complications was negligible in this trial. The immunity to diphtheria or tetanus was not altered by vaccination with live measles vaccine.

Child↗
PubMed1966

African horse-sickness killed-virus tissue culture vaccine.

Formalized African horse-sickness (AHS) type 9 virus cultivated in monkey kidney stable (MS) cell cultures was experimentally used for immunizing horses. Inactivated vaccines prepared either from viscerotropic or neurotropic type 9 AHS virus produced antibodies in vaccinated horses. Immunity developed in all horses vaccinated with various amounts of the vaccine, and protected them from infection, when challenged 5 weeks after vaccination.

Animals↗
PubMedDate not supplied

Influence of parenteral nutrition on phospholipid metabolism in posttraumatic rat lungs.

In the current investigation, we studied two groups of rats--one group supplied exogenous phospholipid precursors (carbohydrate plus fat emulsion group) and the other given only calories (carbohydrate group)--to evaluate the effects on surfactant composition by normocaloric alimentation, using a hypovolemic-traumatic shock model. The total phospholipid (PHL) contents of lung tissue were similar in both groups. However, we found differences in the dipalmitoylphosphatidylcholine fraction (DPPC--the most important component of surfactant material) in both lung tissue and lavage fluid. With lipid emulsion, there was an increased fraction of saturated lecithins (mainly DPPC) both in lung tissue and lavage fluid, similar to former studies with hypocaloric alimentation. In this model, those findings suggest that the PHL pattern does not depend on the quantity of caloric supply, but, rather, on the infusion composition. The enhanced DPPC content is further reflected in improved surfactant status: lipid in parenteral nutrition (PN) may exert a direct salutary effect on lung mechanics.

1,2-Dipalmitoylphosphatidylcholine↗