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Biomedical subjects

R Ehrlich

Publications and source records attributed to R Ehrlich.

At least 163 records · Page 9Linked to original sources
PubMed1993

Aberrant biosynthesis and transport of class I major histocompatibility complex molecules in cells transformed with highly oncogenic human adenoviruses.

The expression of class I major histocompatibility complex antigens on the surface of cells transformed by adenovirus 12 (Ad12) is generally very low. The absence of class I antigens correlates with the high oncogenicity of this virus. In primary embryonal fibroblasts from transgenic mice that express both endogenous H-2 genes and a miniature swine class I gene (PD1), Ad12-mediated transformation results in complete suppression of cell surface expression of class I antigens, but only 50% of the cell lines tested demonstrated decreased steady state levels of class I mRNA. The complete absence of cell surface class I antigens is accompanied by decreased levels of newly synthesized class I molecules. Those molecules that are immunoprecipitated by class I-specific antibodies are assembled with beta 2-microglobulin, but their transport through the Golgi is inefficient. The biosynthesis of both the endogenous H-2K, H-2D, and the transgene product, PD1, is similarly altered in the transformed cells. The results suggest that Ad12 transformation is associated with both reduced synthesis rate and inefficient transport of class I molecules to the cell surface. This might be a general mechanism by which virus-infected or -transformed cells escape immune surveillance.

Adenoviruses, Human↗
PubMed1993

A developmentally regulated gene of Echinococcus granulosus codes for a 15.5-kilodalton polypeptide related to fatty acid binding proteins.

A stage-specific expressed gene has been isolated from a cDNA expression library of Echinococcus granulosus protoscolices. The isolated clone contains the complete coding sequence. The corresponding protein (EgDf1) has a molecular weight of 15.5 kDa and is expressed at the tegumental level in the protoscolices, being undetectable in the germinal layer of the metacestode. This protein shares an important homology with a family of low-molecular weight proteins involved in the binding of hydrophobic ligands. This family includes a protein of Schistosoma mansoni (Sm 14) that has immunoprotective activity in rodents. Histochemical and metabolic data already reported for E. granulosus suggest that EgDf1 could be a molecular marker for early events in the process of protoscolex differentiation.

Amino Acid Sequence↗
PubMed1993

Molecular cloning and characterization of actin genes from Echinococcus granulosus.

An Echinococcus granulosus genomic library has been screened with a mouse beta-actin cDNA probe. Two clones carrying DNA fragments of about 15 kb, possibly derived from the same genome region, have been isolated. This 15-kb genomic region includes 2 actin-related sequences (EgactI and EgactII) separated by about 4 kb. The nucleotide sequences of both genes were determined. The EgactI sequence presents no introns, but an intron of 591 bp was observed in the EgactII sequence. The genes potentially encode 375 and 376 amino-acid-long actins, respectively, with a homology of 85.3%. The deduced amino acid sequences from both genes were compared to the actin sequences from other organisms, showing similarities ranging from 63.5% to 90.6%. The nucleotide sequence of a partial actin cDNA clone has been determined. The deduced amino acids sequence showed a homology of 90.3% and 88.0% in relation to the EgactI and EgactII sequences respectively, suggesting the existence of at least one more actin gene in E. granulosus. This hypothesis is reinforced by the number of bands detected in the Southern blot analysis. Experiments based on the amplification of DNA segments using 3'-specific actin primers indicate that the EgactI gene is transcribed in protoscoleces.

Actins↗
PubMed1993

Acute pulmonary edema after polyethylene glycol intestinal lavage in a child.

OBJECTIVE: To report the case of an eight-year-old girl, without preexisting cardiac or renal disease, who developed acute pulmonary edema and severe respiratory distress after balanced electrolyte with polyethylene glycol (BE-PEG) intestinal lavage. CASE SUMMARY: During the nasogastric infusion of a one-liter dose of BE-PEG (OCL, Abbott), the patient experienced abdominal discomfort, gagging, vomiting and coughing. After the nasogastric infusion, the patient again had emesis, developed tachypnea, intercostal retractions, and acute respiratory distress. She received oxygen and subsequently required intubation and ventilatory support. Physical examination revealed pulmonary congestion bilaterally but no signs of cardiac failure or sepsis. Chest X-ray revealed bilateral pulmonary edema. Ventilatory support was continued for 36 hours and the patient was extubated after two days. DISCUSSION: Enteral BE-PEG may have caused acute pulmonary edema secondary to aspiration or systemic fluid overload. Although the exact cause remains unknown, the close temporal onset of pulmonary edema after BE-PEG administration in an otherwise healthy child suggests a causal relationship. CONCLUSIONS: This case should alter clinicians to the potential for significant morbidity with BE-PEG solutions, particularly if used in outpatient settings. Patients who receive BE-PEG should be closely observed and monitored for potential aspiration, excessive infusion rates, and gastrointestinal symptoms to optimize efficacy and reduce morbidity.

Acute Disease↗
PubMed1992

Homeoboxes in flatworms.

A search for homeobox-containing genes was done in the genome of a primitive metazoan, the parasitic tapeworm Echinococcus granulosus. Five different homeoboxes were isolated, none of them belonging to the classical Antennapedia-type. Three of the homeodomains are similar to those from the Drosophila melanogaster NK-type genes. The fourth homeodomain shares extensive identity with that of the recently reported homeobox-containing gene goosecoid from Xenopus laevis. The third helix (the recognition helix) of the fifth isolated homeodomain is identical to that of the Xlim-1 gene of X. laevis and the lin11 gene of Caenorharbditis elegans. Using PCR, some Antennapedia-type homeoboxes were cloned from the genome of two other Platyhelminthes, Dugesia tigrina (planaria) and Fasciola hepatica. These data suggest that, contrary to what is found for the majority of the more complex metazoans, Platyhelminthes contain few homeobox genes belonging to the Antennapedia-type.

Amino Acid Sequence↗