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D Riley

Publications and source records attributed to D Riley.

At least 127 records · Page 7Linked to original sources
PubMed1990

The progesterone receptor stimulates cell-free transcription by enhancing the formation of a stable preinitiation complex.

Highly purified chicken progesterone receptor (cPR) is shown to stimulate RNA synthesis directly in an in vitro transcription assay. Stimulation of transcription by cPR requires the presence of progesterone response elements (PREs) in the template and can be specifically inhibited by addition of competitor oligonucleotides containing PREs. Binding of receptor to two PREs is cooperative and leads to synergistic (27-fold) stimulation of transcription. A purified fusion protein containing the DNA binding domain of cPR linked to yeast ubiquitin was produced in E. coli and also functions in the transcription assay. Using this in vitro transcription system, we demonstrate that hormone-free cPR activated by salt treatment induces transcription of a test gene in a hormone-independent manner. Finally, we present evidence that the progesterone receptor acts by facilitating the formation of a stable preinitiation complex at the target gene promoter and thus augments the initiation of transcription by RNA polymerase II.

Animals↗
PubMed1990

Vitellogenesis in reptiles as a model for mammalian sex-differentiated hepatic protein synthesis.

The stimulation of yolk protein synthesis by estrogen is a characteristic of female non-mammalian vertebrates; in mammals, or their reptilian ancestors, however, vitellogenesis has been suppressed as a corollary of the evolution of viviparity. It is our hypothesis that progesterone has a dual role in this phylogenetic trend: a) to inhibit myometrial contraction and thus set the stage for internal development of embryos and associated placentation and b) to inhibit yolk protein synthesis in a coordinate manner as placentation became an efficient direct supply of nutrients to the fetus. Despite the absence of vitellogenesis per se in eutherian mammals, significant sex-differentiated hepatic protein-lipid synthetic functions remain, which are under complex hormonal control. We have presented evidence that in the reptiles, the central vertebrate group from which the ancestors of modern mammals evolved, the control of yolk protein synthesis is also complex, involving both pituitary hormones (GH, PRL, and LH) and ovarian steroids (estradiol, testosterone, and progesterone). Adequate evidence exists to suggest that mammalian hepatic lipoprotein synthesis and its regulatory elements are phylogenetically derived from their reptilian ancestors and may be better understood in this context. This is of particular relevance to cardiovascular disease in which there is a clear sex bias yet for which no coordinated research program exists which takes into account the relevant phylogenetic history. We believe that reptilian, and possibly avian, models could be used to great advantage to probe the endocrine components of cardiovascular disease.

Animals↗
PubMed1990

Psychogenic dyskinesias in patients with organic movement disorders.

The association of psychogenic neurological features with organic neurological disease is commonly acknowledged. However, the occurrence of psychogenic dyskinesias in patients with underlying organic movement disorders is not well recognized. Six cases of psychogenic dyskinesias complicating preexisting organic movement disorders are described. This possibility must be carefully considered and excluded before an unusual movement disorder can be considered entirely psychogenic.

Adult↗
PubMed1990

Vertebrate vitellogenesis: molecular model for multihormonal control of gene regulation.

The stimulation of yolk protein synthesis by estrogen is a characteristic of female non-mammalian vertebrates; in mammals, however, vitellogenesis has been suppressed as a corollary of the evolution of viviparity. It is our hypothesis that progesterone has a dual role in this phylogenetic trend; a) to inhibit myometrial contraction and thus set the stage for internal development of embryos and associated placentation, b) to inhibit yolk protein synthesis as placentation became an efficient direct supply of nutrients to the fetus. We have presented evidence that in the reptiles, the central vertebrate group from which the ancestors of modern mammals evolved, the control of yolk protein synthesis is complex, involving both pituitary and ovarian steroids (estradiol, testosterone and progesterone). This system provides an excellent model for the multihormonal contents of gene regulation involving both + and - controls.

Animals↗
PubMed1989

Blood use in head and neck tumor surgery. Potential for autologous blood.

Recent increased concern regarding the risks of homologous blood transfusion led us to examine the use of blood products for head and neck tumor surgery. Major head and neck surgical procedures at three University of Washington (Seattle)-affiliated hospitals during 1987 were reviewed. Seventy-seven patients were identified. Parameters studied included the following: tumor site and stage, prior treatment, surgical procedure, preoperative and postoperative hematocrit values, estimated blood loss, operative and postoperative blood product use, and operative time. Data were grouped by procedure. Maxillectomy/midface procedures showed the highest average estimated blood loss (1037 mL) and the highest average blood use (1.5 units), followed by composite resections (883 mL and 0.8 units) and laryngectomies (724 mL and 0.9 units). When the data were subgrouped, larynogopharyngectomy (1450 mL and 4.0 units) and composite resection with mandibular swing (1300 mL and 1.0 units) showed the highest blood loss and blood product use. In the assessable groups, previous administration of radiation did not make a significant difference in blood loss or procedure time. However, blood loss correlated well with procedure time in all groups. The great majority of patients met all requirements to function as blood donors (84%). Sixty-five percent of patients met all criteria and used less than 2 units of blood, making autologous blood a reasonable option for the majority of patients with head and neck tumors.

Blood Transfusion, Autologous↗
PubMed1989

Displaced subcapital fractures of the femur: a prospective randomized comparison of internal fixation, hemiarthroplasty and total hip replacement.

In a prospective trial of 278 patients aged over 65 years, treatment of displaced subcapital fractures was randomly allocated to closed reduction and internal fixation with a sliding compression screwplate, Moore hemiarthroplasty, or total hip treatment with a Howse semicaptive prosthesis. One year after operation there was little difference between the three groups in mortality (25 per cent) or general complications. The revision rate within the first year was highest for internal fixation (25 per cent), but many of the replacements also required a further anaesthetic for reduction of a dislocation (Moore, 11 per cent; Howse 12.5 per cent). Total hip replacement resulted in the least pain and most mobility at 1 year, while hemiarthroplasty was worst in these respects. We conclude that internal fixation and particularly primary total hip replacement should be given serious consideration in the management of the elderly patient with a displaced subcapital fracture.

Aged↗