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D Goff

Publications and source records attributed to D Goff.

At least 37 records · Page 2Linked to original sources
PubMed1993

Growth and cholesterol oxidation by Mycobacterium species in Tween 80 medium.

Mycobacterium strain DP was isolated from marine coastal sediment and tested for its ability to oxidize cholesterol in Tween 80-cholesterol (2.59 mM) medium. Strain DP degraded cholesterol to 4-cholesten-3-one (cholestenone), 4-androsten-3,17-dione (AD), 1,4-androstadien-3,17-dione (ADD), testosterone, and 1-dehydrotestosterone (DHT). Cholesterol disappeared in about 4 days. Cholestenone, AD, testosterone, and DHT accumulations were transient with peak concentrations of 300, 600, 30 to 40, and 21 microM. ADD production peaked after 6 days with a concentration of 1,100 microM. Peak ADD concentrations and production rates compared well with those reported for strain NRRL B3683 on cyclodextrin medium. Tween 80 medium was superior to finely dispersed cholesterol particles for both strains. In comparison, NRRL B3683 (patented for its ability to accumulate AD and ADD) on Tween 80 medium transiently accumulated more AD (approximately 1,000 microM) than did strain DP, but ADD accumulations (200 microM) were significantly lower than those for strain DP. Strain DP could be adapted to grow on ADD, which was initially inhibitory at 3.25 mM. ADD-adapted strain DP cultures produced approximately four times as much DHT from ADD than unadapted cultures did from cholesterol, showing that additional manipulation might enhance testosterone production. We believe that ADD toxicity might account for the low ADD accumulations by NRRL B3683 in Tween 80 medium.

Androstadienes↗
PubMed1992

Sympathetic responses to induction of anesthesia in humans with propofol or etomidate.

Anesthetic induction with propofol commonly results in hypotension. This study explored potential mechanisms contributing to hypotension by recording cardiovascular responses including sympathetic neural activity from patients during induction of anesthesia with propofol (2.5 mg.kg-1 plus 200 micrograms.kg-1.min-1) or, for comparison, etomidate (0.3 mg.kg-1 plus 15 micrograms.kg-1.min-1). Twenty-five consenting, nonpremedicated, ASA physical status 1 and 2, surgical patients were evaluated. Measurements of R-R intervals (ECG), blood pressure (radial artery), forearm vascular resistance (plethysmography), and efferent muscle sympathetic nerve activity ([MSNA] microneurography: peroneal nerve) were obtained at rest and during induction of anesthesia. In addition, a sequential bolus of nitroprusside (100 micrograms) followed by phenylephrine (150 micrograms) was used to obtain data to quantitate the baroreflex regulation of cardiac function (R-R interval) and sympathetic outflow (MSNA) in the awake and anesthetized states. Etomidate induction preserved MSNA, forearm vascular resistance, and blood pressure, whereas propofol reduced MSNA by 76 +/- 5% (mean +/- SEM), leading to a reduction in forearm vascular resistance and a significant hypotension. Both cardiac and sympathetic baroslopes were maintained with etomidate but were significantly reduced with propofol, especially in response to hypotension. These findings suggest that propofol-induced hypotension is mediated by an inhibition of the sympathetic nervous system and impairment of baroreflex regulatory mechanisms. Etomidate, conversely, maintains hemodynamic stability through preservation of both sympathetic outflow and autonomic reflexes.

Adult↗
PubMed1991

Activation of endothelial-leukocyte adhesion molecule 1 (ELAM-1) gene transcription.

Leukocyte adherence to endothelium is in part mediated by the transient expression of endothelial-leukocyte adhesion molecule 1 (ELAM-1) on endothelial surfaces stimulated by tumor necrosis factor alpha (TNF), interleukin (IL) 1, or bacterial lipopolysaccharide (LPS). The intracellular factors controlling induction of ELAM-1 mRNA and protein are unknown. In nuclear runoff experiments with cultured human umbilical vein endothelial cells (HUVEC), we demonstrate that transcriptional activation of the ELAM-1 gene occurs following stimulation with TNF. Sequence analysis of the 5' flanking region of the ELAM-1 gene reveals consensus DNA-binding sequences for two known transcription factors, NF-kappa B and AP-1. Gel mobility shift assays demonstrate that TNF, IL-1, or LPS (but not IL-2, IL-4, IL-6, interferon gamma, histamine, or transforming growth factor beta) induces activation of NF-kappa B-like DNA binding activity in HUVEC. In contrast, neither TNF, IL-1, nor LPS activates proteins that bind to an AP-1 consensus sequence under these experimental conditions. Phorbol 12-myristate 13-acetate, a known activator of protein kinase C (PKC), weakly induces NF-kappa B-like activity, ELAM-1 mRNA, and ELAM-1 surface expression in HUVEC. However, TNF, IL-1, and LPS do not activate PKC in HUVEC at doses that strongly induce NF-kappa B-like protein activation and ELAM-1 gene expression. PKC blockade with H7 does not inhibit activation of these NF-kappa B-like proteins but does inhibit ELAM-1 gene transcription. We conclude that PKC-independent activation of NF-kappa B in HUVEC with TNF, IL-1, or LPS is associated with, but not sufficient for, activation of ELAM-1 gene transcription.

Base Sequence↗
PubMed1991

Cloning of an alternate form of vascular cell adhesion molecule-1 (VCAM1).

Vascular cell adhesion molecule-1 (VCAM1) of the Ig superfamily is induced by the inflammatory cytokines interleukin-1 and tumor necrosis factor on human umbilical vein endothelial cells (HUVECs). It binds to mononuclear leukocytes via the integrin VLA-4. We have cloned and expressed a cDNA encoding a new form of human VCAM1 containing an additional Ig homologous domain inserted between the third and fourth domains of the original six-domain protein. Characterization of mRNA from HUVECs from three individuals at various time points after induction by tumor necrosis factor indicates that both the long and short VCAM1 mRNAs are made by all three individuals, with the long form predominating quantitatively. Immunoprecipitation of VCAM1 protein from cos7 cells transfected with each cDNA and from cultured endothelial cells followed by deglycosylation suggests that the long form is the major form found on endothelium. The two forms may result from alternate splicing of a precursor mRNA. Both forms support adhesion of VLA-4-expressing cell lines.

Amino Acid Sequence↗
PubMed1990

ELFT: a gene that directs the expression of an ELAM-1 ligand.

The LECCAMs are a family of cell adhesion molecules implicated in certain inflammatory processes. ELAM-1, a LECCAM found on the surface of activated endothelial cells, can mediate adhesion of neutrophils, monocytes, and certain cell lines to endothelial cells in vitro. No ligand for any LECCAM has yet been fully characterized. Here we report the cloning of a cDNA, ELFT (ELAM-1 ligand fucosyltransferase), that can confer ELAM-1 binding activity when transfected into nonbinding cell lines. ELFT encodes a 46 kd protein that has alpha(1,3)fucosyltransferase activity, suggesting that a fucosylated carbohydrate structure is an essential component of the ELAM-1 ligand. Furthermore, ELFT is expressed specifically in cell types that bind to ELAM-1, suggesting that this enzyme is an important regulator of inflammatory events in vivo.

Amino Acid Sequence↗
PubMed1990

Endothelial leukocyte adhesion molecule 1: direct expression cloning and functional interactions.

A cDNA for endothelial leukocyte adhesion molecule 1 (ELAM-1) was isolated by transient expression in COS-7 cells of a subtracted cDNA library from cytokine-treated human umbilical vein endothelial cells (HUVECs), with selection of ELAM-1-expressing clones by adhesion of transfected cells to the human promyelocytic cell line HL-60. This cloning method requires neither antibody nor purified ligand. ELAM-1-expressing COS cells bind the promyelocytic cell line HL-60 by a Ca2(+)-dependent but temperature-independent mechanism. Although ELAM-1 is homologous to mammalian lectins, its interaction with HL-60 cells is not inhibited by simple carbohydrate structures. ELAM-1-expressing COS cells also bind human neutrophils and the human colon carcinoma cell line HT-29, but not the B-cell line Ramos. However, Ramos cells adhere to cytokine-treated HUVECs but not control HUVECs, confirming the existence of other inducible adhesion molecules. In addition, the binding of HL-60 cells or neutrophils to ELAM-1-expressing COS cells is not inhibited by a monoclonal antibody (60.3) directed to an inhibitory epitope on CD18, indicating that the ELAM-1 ligand, although uncharacterized, is not a member of the CD11/CD18 family.

Amino Acid Sequence↗
PubMed1990

Oral physostigmine treatment for patients with presenile and senile dementia of the Alzheimer's type: a double-blind placebo-controlled trial.

Twelve patients aged 53 to 89 years with presenile or senile dementia of the Alzheimer's type participated in a treatment trial of oral physostigmine. Patients first received the drug during an open dose-finding phase. In a double-blind crossover design phase, the patients' memory performance during treatment with an optimal memory-enhancing dose was compared with memory performance during placebo treatment. Response to medication was assessed by the Delayed Recognition Span Test, the Selective Reminding Test, and the Alzheimer's Disease Assessment Scale. Intergroup differences in response to physostigmine were nonsignificant. Age at onset of the disease did not differentiate partial responders from nonresponders.

Administration, Oral↗
PubMed1989

Pharmacy-laboratory interactions: a unique method to control antibiotic costs.

Because a large percentage of hospital antibiotic use is regarded as inappropriate, hospital pharmacists must investigate ways of decreasing such usage. A unique approach was evaluated for its impact on cost-effective antibiotic therapy. By functioning as a team, the pharmacy and laboratory departments implemented the following steps: cost-code index on antimicrobial susceptibility and organism identification reports; suppression of cost-ineffective antibiotics within the same pharmacologic group from the antimicrobial susceptibility reports; design of minimum inhibitory concentration panels to conform to the hospital formulary; daily delivery of the antimicrobial susceptibility reports to the pharmacy. Of the 1078 documented therapeutic interventions by the clinical pharmacist, 100 were randomly selected for review, 62% of which involved direct interaction with the laboratory. Estimated cost savings due to these interactions were $8214; annual savings were $88,554. The results of this study show the importance of pharmacy departments forming and maintaining lines of communication with the hospital laboratory department.

Anti-Bacterial Agents↗
PubMed1988

A comparative study of combination chemotherapy versus marrow transplant in first remission in adult acute lymphoblastic leukaemia.

The results of conventional chemotherapy in adult acute lymphoblastic leukaemia (ALL) have not improved substantially in recent years. The present study is based on a flexible policy of marrow transplantation (allograft and autograft without marrow purging) in first remission compared with a group treated with standard maintenance therapy after a common induction sequence. The actuarial disease free survival (DFS) and actuarial overall survival (OS) at 3 years for autologous marrow grafted patients was 30% and 65% respectively. The allogeneic transplant group had DFS of 30% and OS at 3 years of 38% compared with DFS (12%) and OS (12%) for patients on 6-mercaptopurine and methotrexate maintenance. The actuarial disease free survival calculations include patients on protocol not entering remission, therefore, giving the worst possible result. We conclude that high dose chemo/radiotherapy with autologous marrow rescue in first remission followed by no maintenance provides better results in terms of overall survival and quality of life than standard ALL maintenance in adult patients. Results for allogeneic transplant in ALL are less good in terms of duration and quality of survival and the majority of deaths are related to causes other than leukaemic relapse.

Adolescent↗
PubMed1981

Characteristics of the chemotactic factor-mediated cell swelling response of tumor cells.

The interaction between Walker carcinosarcoma cells, maintained in ascites form in noninbred Sprague-Dawley rats and in cell culture, and appropriate factors induced directed migration (chemotaxis) of these cells as measured in the Boyden chamber assay. The response of the tumor cells to these factors was very similar to that of leukocytes to their chemotactic factors. In addition to inducing chemotactic responses, the interaction between Walker carcinosarcoma cells and appropriate chemotactic factors also led to a swelling of the cells, which could be measured with the use of Coulter Channelyzer C-1000. Associated with the cell-swelling response was a temporary drop in the cell count of a suspension of cells as measured with the use of a Coulter counter, model ZBI. These responses were also similar to what occurs when leukocytes interact with their chemotactic factors. When the suspension of tumor cells was pretreated with 2-deoxyglucose, the responses measured with the Coulter counters were almost completely abrogated. In contrast to this, treatment of the cells with various chemical agents, including cytochalasin B, colchicine, cycloheximide, chlorpromazine, and the Ca2+ ionophore A23187 failed to significantly reduce the cell-swelling response. Cytochalasin B slightly potentiated the response. These similarities to the responses of leukocytes suggested a common underlying mechanism.

Animals↗