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Biomedical subjects

D Gutmann

Publications and source records attributed to D Gutmann.

11 recordsLinked to original sources
PubMed1996

Ras-GTP levels are elevated in human NF1 peripheral nerve tumors.

Neurofibromin, the gene product of NF1, is a Ras GTPase Activating Protein. The absence of neurofibromin leads to increased levels of Ras-GTP, which contributes to the proliferation of NF1 neurogenic sarcoma cell lines. Whether this pathogenic mechanism is applicable to benign and malignant peripheral nerve tumours from NF1 and non NF1 patients is not known, due to lack of a tissue based assay. We have adapted a colorimetric enzymatic assay for determining levels of Ras bound guanine nucleotides in tissues. Ras-GTP levels were increased in NF1 neurogenic sarcomas (15 times) and benign NF1 neurofibromas (four times), compared to non NF1 schwannomas. Neurofibromin was not expressed in NF1 sarcomas, in support of its important negative Ras regulatory role in the pathogenesis of NF1 peripheral nerve tumors.

Base Sequence↗
PubMed1992

Mourning the loss of "self as father": a longitudinal study of fatherhood among the Druze.

It is within the context of the parent-child relationship--through the processes of attachment, loss, separation and individuation--that we grow and develop interpersonally and intrapsychically (Bowlby 1969, 1980; Mahler et al. 1975; Pollock, 1989). Most developmentalists agree that changes in the parent-child relationship continue to influence both parents and children throughout the life cycle (Cohen et al. 1984; Colarusso and Nemiroff 1982). While there is a vast body of literature devoted to discussing changes that occur in the parent-child relationship during the "formative years," little has been written about what happens to that relationship after the children leave home to start families of their own. Moreover, most researchers investigate the processes of attachment, loss, separation and individuation in terms of the child's development. Little is known about how the child's quest for independence affects the psychological development of his/her parents. Those writers who have addressed the issue of individuation in later life tend to focus on the adult child's continuing struggle to separate and individuate from his/her real or imagined parents (Levinson, 1978).

Adaptation, Psychological↗