C George-Nascimento

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Epidermal regeneration depends on mitosis and migration of keratinocytes. Epidermal growth factor is known to stimulate growth of keratinocytes in vitro, thus it might be expected to promote wound healing. The results of this study show that topical application of biosynthetic human epidermal growth factor accelerates epidermal regeneration in(More)
Platelet-derived growth factor (PDGF) is a dimeric factor stabilized by disulfide bonds. Using an approach involving partial reduction of PDGF, we have identified the 2nd and 4th cysteine residues in the PDGF chains as the cysteine residues forming interchain disulfide bonds. Analysis of PDGF mutants in which the 2nd and 4th cysteine residues were mutated(More)
MC3T3-E1 murine osteoblasts produce insulin-like growth factor (IGF)-binding protein-4 (IGFBP-4)-degrading proteinase activity, which is inhibited by IGFBP-3 and a highly basic, C-terminal domain of IGFBP-3. Of all the other five IGFBPs, IGFBP-5 and -6 share the highest degree of homology with this domain of IGFBP-3; therefore, we investigated whether these(More)
Expression vectors were constructed for the production of various domains of the envelope gene product of the SF-2 isolate of human immunodeficiency virus (HIV) in the yeast Saccharomyces cerevisiae. Serum specimens from HIV seropositive blood donors reacted in immunoblot assays with recombinant polypeptides from both the gp120 and gp41 coding regions of(More)
Current commercial hepatitis B virus (HBV) anti-HBe immunoassays are designed so that anti-HBe is detectable only in the absence of excess HBeAg. Recently, with the use of direct anti-HBe assays, anti-HBe was detected in individuals who had been seropositive for several years for HBeAg [Maruyama et al. (1993) J. Clin. Invest. 91:2586-2595]. Although(More)
Infection with the retrovirus that is the etiological agent of acquired immune deficiency syndrome (AIDS) is characterized by the development of antiviral antibodies. To generate reagents for studying immune responses to individual viral proteins, we have produced viral antigens in microorganisms by recombinant DNA techniques. Large amounts of the major(More)
Epidermal growth factor (EGF), present in high concentrations in the milk of various species, is biologically active following oral administration to young animals. Although in vivo studies show gastrointestinal processing of dietary EGF during early postnatal development, the relative importance of luminal and mucosal digestion in such processing is(More)
Epidermal growth factor (EGF), present in high concentrations in milk, may play a role in growth of the gastrointestinal tract. Resistance to proteolytic degradation in the stomach is necessary if ingested EGF is to function within the gastrointestinal tract. Although EGF stability to low pH and proteases predicts gastric survival, the extent of digestion(More)
All HIV seronegative (HIV Ab-) and most HIV seropositive (HIV Ab+) individuals' lymphocytes failed to proliferate in primary cultures in response to purified HIV or to recombinant envelope and core antigens of HIV, even in the presence of recombinant interleukin 2 (rIL-2). Most HIV Ab- and HIV Ab+ individuals' lymphocytes, however, could proliferate or be(More)
Long-term storage of recombinant human epidermal growth factor (EGF), an important promoter of cell division, results in its conversion to a new species that elutes later than native EGF on a reverse-phase column. This new species, called EGF-X, has only 20% of the biological activity of native EGF. Peptide mapping indicated that the primary structure of(More)