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D P Cox

Publications and source records attributed to D P Cox.

10 recordsLinked to original sources
PubMed2000

Ameloblastic carcinoma ex ameloblastoma of the mandible with malignancy-associated hypercalcemia.

Ameloblastoma is a rare, locally destructive, benign neoplasm of the jawbones, which arises from epithelium derived from the epithelial components of the developing tooth. Ameloblastic carcinoma is the term used to designate any ameloblastoma in which there is histologic evidence of malignancy in the primary tumor, regardless of whether it has metastasized. Most ameloblastic carcinomas are presumed to have arisen de novo, with few cases of malignant transformation of ameloblastoma being apparent. Hypercalcemia is the most common metabolic complication of malignancy. Although malignancy-associated hypercalcemia is often reported in association with other malignancies, it is exceedingly unusual in association with ameloblastoma, malignant ameloblastoma, or ameloblastic carcinoma. We describe a patient with multiple recurrences of ameloblastoma, with subsequent malignant transformation presenting with malignancy-associated hypercalcemia.

Adult↗
PubMed1985

The dexamethasone suppression test in agoraphobia.

Patients diagnosed as having agoraphobia with panic attacks by DSM-III criteria were evaluated with the dexamethasone suppression test (DST). Depressive symptoms were assessed using the Beck Depression Inventory, the Depression Scale of the Minnesota Multiphasic Personality Inventory, and the Hamilton Rating Scale for Depression. Of 97 patients tested, 12.4% had a positive DST. These findings are consistent with earlier reports that found an incidence of abnormal DSTs between 11% and 15% in agoraphobic patients. Abnormal DSTs did not correlate with levels of depression on any of the depression measures.

Adult↗
PubMed1980

Biological Process for Converting Naphthalene to cis-1,2-Dihydroxy-1,2-Dihydronaphthalene.

A biological process for converting naphthalene to cis-1,2-dihydroxy-1,2-dihydronaphthalene (DHD) catalyzed by Pseudomonas putida strain 119 was optimized in flask experiments. These studies revealed the following: (i) P. putida 119 can propagate efficiently and produce DHD when supplied one of several carbon sources and naphthalene; (ii) maximum DHD production by P. putida 119 occurs in logarithmic-growth-phase cells and decreases at various rates in the stationary growth phase, depending upon the carbon source used; (iii) several analogs of salicylic acid can be used as effective inducers of naphthalene metabolism in P. putida cells growing on glucose; and (iv) the addition of chemical surfactants to naphthalene-cell (P. putida 119) mixtures stimulates DHD production.

Journal Article↗
PubMed1979

Microbial conversion of ethylbenzene to 1-phenethanol and acetophenone by Nocardia tartaricans ATCC 31190.

A culture of Nocardia tartaricans ATCC 31190 was capable of catalyzing the conversion of ethylbenzene to 1-phenethanol and acetophenone while growing in a shake flask culture with hexadecane as the source of carbon and energy. This subterminal oxidative reaction with ethylbenzene appears not to have been previously reported for Nocardia species. When N. tartaricans was grown on glucose as its source of carbon and energy and ethylbenzene was added, no subsequent production of 1-phenethanol or acetophenone was observed. The mechanisms of 1-phenethanol and acetophenone production from ethylbenzene are thought to involve a subterminal oxidation of the alpha-carbon of the alkyl group to 1-phenethanol followed by biological oxidation of the latter to acetophenone.

Acetophenones↗
PubMed1973

Effect of phosphate and other anions on trimethylarsine formation by Candida humicola.

Phosphate inhibited the formation of trimethylarsine from arsenite, arsenate, and monomethylarsonate, but not from dimethylarsinate, by growing cultures of Candida humicola. Phosphite suppressed trimethylarsine production by growing cultures from monomethylarsonate but not from arsenate and dimethylarsinate, and hypophosphite caused a temporary inhibition of both proliferation and the conversion of these three arsenic sources to trimethylarsine. Resting cells of C. humicola derived from cultures grown in arsenic-free media generated the volatile arsenical only after a lag phase. High antimonate concentrations reduced the rate of conversion of arsenate to trimethylarsine by resting cells, but nitrate was without effect.

Antimony↗
PubMed1967

Effect of different nutritional conditions on the synthesis of tricarboxylic acid cycle enzymes.

The effect of various nutritional conditions on the levels of Krebs cycle enzymes in Bacillus subtilis, B. licheniformis, and Escherichia coli was determined. The addition of glutamate, alpha-ketoglutarate, or compounds capable of being catabolized to glutamate, to a minimal glucose medium resulted in complete repression of aconitase in B. subtilis and B. licheniformis. The synthesis of fumarase, succinic dehydrogenase, malic dehydrogenase, and isocitric dehydrogenase was not repressed by these compounds. It is postulated that glutamate or alpha-ketoglutarate is the true corepressor for the repression of aconitase. A rapidly catabolizable carbon source and alpha-ketoglutarate or glutamate must be simultaneously present for complete repression of the formation of aconitase. Conditions which repress the synthesis of aconitase in B. subtilis restrict the flow of carbon in the sequence of reactions leading to alpha-ketoglutarate but do not prevent glutamate oxidation in vivo. The data indicate that separate and independent mechanisms regulate the activity of the anabolic and catabolic reactions of the Krebs cycle in B. subtilis and B. licheniformis. The addition of glutamate to the minimal glucose medium results in the repression of aconitase, isocitric dehydrogenase, and fumarase, but not malic dehydrogenase in E. coli K-38.

Bacillus↗