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D S Dolberg

Publications and source records attributed to D S Dolberg.

5 recordsLinked to original sources
PubMed1994

The human vomeronasal system.

We studied the functional characteristics of the vomeronasal system in clinically normal adult subjects of both sexes (ages 20-45). Chemosensory substances were administered in punctate pulses in a continuous air stream from the tip of a multifunctional miniprobe, which contained a nonpolarizable electrode. Negative potentials with the characteristics of receptor potentials were recorded from the surface of the vomeronasal organ (VNO) and olfactory epithelium (OE) in response to certain substances defined here as vomeropherins (see definition in the introduction of the main text) and to olfactants. Stimulation of the VNO with femtomole amounts of vomeropherins produced a local depolarization with the characteristics of a receptor potential. The same substances produced only a small response from the OE, and no response from the nasal respiratory mucosa. Three vomeropherins PH15, PH78, and PH84 were particularly well recognized by the VNO of most male subjects (p < .01; n = 30). Substances PH30, PH56, and PH94B, produced similar effects in the VNO of most female subjects (p < .01; n = 30). Responses to virtually all vomeropherins exhibited a sexual dimorphism. Stimulation of the OE with the same quantity of odorants 1,8-cineole and l-carvone produced depolarization of 6.8 +/- 2.6 mV, but little or no response in the VNO. Therefore, the human VNO seems to have a unique specificity for certain chemosensory substances when compared to the OE. Administration of PH15 and PH78 to the VNO of male subjects (but not to female subjects) significantly increased electrodermal activity (p < .02) and skin temperature (p < .01). On the other hand, administration of PH84 to the VNO of male subjects decreased skin temperature but had little effect on electrodermal activity. Autonomic changes were accompanied by an increased percentage of alpha-cortical activity for all three vomeropherins. In female subjects (but not in male subjects) vomeropherins PH56 and PH94B significantly increased electrodermal activity (p < .01), skin temperature (p < .01), and alpha-cortical activity (p < .01). Local application of the olfactants 1,8-cineole and l-carvone to the VNO did not trigger autonomic responses or significant changes in the electroencephalographic pattern in male or in female subjects. Our studies indicate the adult human VNO is a functional chemosensory organ with a sexually dimorphic specificity and the ability to transduce signals which modulate certain autonomic parameters.

Adult↗
PubMed1985

Wounding and its role in RSV-mediated tumor formation.

Tumors induced in chickens by Rous sarcoma virus remain localized at the site of injection even though the animals become viremic. Tumors have now been shown to be inducible at other sites if a wound is inflicted or if the tissue is injured by administration of tumor promoters. These findings indicate that local wounding plays a role in the spread of tumorigenicity of Rous sarcoma virus.

Animals↗
PubMed1981

Endogenous type C retroviral sequences of mice are organized in a small number of virus-like classes and have been acquired recently.

We studied endogenous type C virus-related sequences of mice by annealing Moloney murine leukemia virus DNA to agarose gel blot transfers of uninfected mouse cell DNA which had been cleaved with restriction enzymes. We found that many of the endogenous murine leukemia virus-related sequences in mice consist of two organizational classes that are integrated into many different loci. Both of these classes resemble standard murine leukemia virus proviral DNA in both size and sequence organization. All lines of inbred mice examined contained both organizational classes, as did feral isolates of Mus musculus domesticus. However, a related Asian subspecies, Mus musculus molossinus, contained different organizational classes of endogenous murine leukemia virus-related sequences. Among inbred strains and feral isolates of M. musculus domesticus, the murine leukemia virus-related sequences were present at different loci. This suggested that most of these sequences were acquired relatively recently during subspeciation and inbreeding.

Animals↗
PubMedDate not supplied

Inability of Rous sarcoma virus to cause sarcomas in the avian embryo.

The injection of Rous sarcoma virus (RSV) into the wing web of newly hatched chicks causes a rapidly growing sarcomatous tumour which is palpable within 1 week of inoculation; and cultures of fibroblasts derived from chick embryos (CEF) and infected with RSV become rapidly transformed. Genetic studies have determined that expression of a single viral gene, designated v-src, is necessary for neoplastic transformation. This gene codes for a 60,000-molecular weight phosphoprotein termed pp60SPC , which possesses a protein kinase activity that phosphorylates polypeptides on tyrosine residues and is constitutively expressed in infected CEF cells. It has been suggested that transformation, and possibly tumorigenesis, may result solely from the consequences of this increase in tyrosine phosphorylations. The pathogenicity of RSV in chick embryos in ovo is less clear. Murphy and Rous suggested that RSV may have caused tumours in "various tissues" of "some embryos", but the subsequent studies of Milford and Duran - Reynals , as well as several other laboratories, failed to find any evidence of intraembryonic tumours in RSV-infected early embryos. The findings of Duran - Reynals , if correct, cannot be explained easily in view of our present understanding of RSV tumorigenicity. Thus, we have re-examined the interaction of RSV with the avian embryo and confirm here that RSV is nontumorigenic and non-teratogenic when microinjected into day 4 chicken embryos. In addition, we found that (1) the virus not only replicates in the embryo, but it also expresses an active src-specific protein kinase and (2) once the cells from the infected limbs are disrupted and placed in culture, they are capable of expressing the transformed phenotype after a 24-h delay.

Animals↗