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Biomedical subjects

Geoffrey A Cordell

Publications and source records attributed to Geoffrey A Cordell.

At least 19 recordsLinked to original sources
PubMed2006

Cytotoxic clerodane diterpenoids from the leaves of Premna tomentosa.

Three clerodane diterpenoids, premnones A-C (1-3), were isolated from a chloroform-soluble fraction of Premna tomentosa along with four known flavonoids and three known triterpenoids. Among these isolates, premnones A-C exhibited cytotoxic activity when evaluated against a small panel of tumor cell lines. However, premnone A was found to be inactive when evaluated in a follow-up in vivo hollow fiber assay at the highest dose tested (50mg/kg), using LNCaP, Lu1, and MCF-7 cells.

Cell Line, Tumor↗
PubMed2006

Survey of medical ethnobotanicals for dental and oral medicine conditions and pathologies.

Ethnomedical questionnaires were distributed in Chicago, Costa Rica, and Colombia to identify the most common over-the-counter (OTC) plant or plant-based products advocated for treating oral pain, ulcerative conditions, and cancer within these locations. Over 100 plants or plant-based herbal preparations and commercial products, purchased from local botanical markets and pharmacies, were advocated for the treatment of oral medicine conditions. Locally familiar and common language names were attributed to the plant products at the time of purchase. Plant products or plant-based commercial products containing plant-based essential oils, anesthetic constituents, and or chemical compounds recommended as OTC oral medicine preparations were systematized, tabulated, and correlated with the published phytotherapeutic literature. Though pharmacognostic research is available for some of the species collected, further ethnographic research is needed to correlate common names with the accurate taxonomic identification for each plant species. Furthermore, epidemiological research is needed to verify the use and standardized dosage for OTC ethnomedicine preparations for oral medicine conditions. Pharmacognostic research and clinical trails which can verify taxonomy, dose, safety, active principles, and efficacy of these OTC oral medicine products must be enhanced in order to verify the claimed validity in contemporary, global, oral medicine practice.

Data Collection↗
PubMed2006

Bioreduction of aldehydes and ketones using Manihot species.

Biocatalysis constitutes an important tool in organic synthesis, especially for the preparation of chiral molecules of biological interest. A series of aliphatic and aromatic aldehydes and two ketones were reduced using plant cell preparations from Manihot esculenta and Manihot dulcis roots. The reduced products were typically obtained in excellent yields (80-96%), and with excellent enantiomeric excess (94-98%), except for vanillin. Esters, a nitrile, and an amide were also examined, but were not reduced. Preliminary conversion rate studies are reported. This is the first attempt to perform the biotransformation of carbonyl compounds using Manihot species.

Aldehydes↗
PubMed2006

Relationships between inhibitory activity against a cancer cell line panel, profiles of plants collected, and compound classes isolated in an anticancer drug discovery project.

In an attempt to determine the relationships between the plant profiles (country of collection, taxonomy, plant part) and the compound classes isolated with cytotoxic activity against a panel of human tumor cell lines, the data compiled from a 15-year anticancer drug-discovery project were subjected to an analysis of variance (ANOVA). The results indicate significant trends in cytotoxic activity relative to collection location, taxonomy, plant part, and compound classes isolated. Plant collections were made in tropical forests in six countries, with collections from Ecuador resulting in higher activity than those from Indonesia and Peru. Interestingly, collections from Florida were not statistically different than those from the countries with higher biodiversity. One hundred and forty-five families were represented in the collections, with the Clusiaceae, Elaeocarpaceae, Meliaceae, and Rubiaceae having low ED50 (half maximal effective dose) values. Especially active genera included Aglaia, Casearia, Exostema, Mallotus, and Trichosanthes. Roots and below-ground plant materials were significantly more active than above-ground materials. Cucurbitacins, flavaglines, anthraquinones, fatty acids, tropane alkaloids, lignans, and sesquiterpenoids were significantly more active than xanthones and oligorhamnosides. The results from this study should serve as a guide for future plant collection endeavors for anticancer drug discovery.

Antineoplastic Agents, Phytogenic↗
PubMed2006

Cytotoxic lignans from the stems of Helicteres hirsuta collected in Indonesia.

Cytotoxicity-guided fractionation of the stems of Helicteres hirsuta, of Indonesian origin, led to the isolation and identification of six lignans, namely, (+/-)-pinoresinol, (+/-)-medioresinol, (+/-)-syringaresinol, (-)-boehmenan, (-)-boehmenan H and (+/-)-trans-dihydrodiconiferyl alcohol. Of these isolates, (+/-)-pinoresinol exhibited potent cytotoxic effects when evaluated against a small panel of cancer cell lines.

Antineoplastic Agents, Phytogenic↗
PubMed2006

Cytotoxic constituents from the stem bark of Dichapetalum gelonioides collected in the Philippines.

Fractionation of an ethyl acetate-soluble extract of the stem bark of Dichapetalum gelonioides, collected in the Philippines, using the LNCaP (hormone-dependent human prostate) cell line as a monitor, led to the purification of three dichapetalin-type triterpenoids [dichapetalins A (1), I (2), and J (3)], along with two dolabrane norditerpenoids (6, 7), and the additional triterpenoids zeylanol (8), 28-hydroxyzeylanol (9), and betulinic acid. Since compounds 1-3 exhibited promising selectivity against the SW626 (human ovarian cancer) cell line, a re-collection of the plant material was carried out, to obtain more of these compounds for additional biological testing. Two further phenylpyranotriterpenoids [dichapetalins K (4) and L (5)] were isolated from the re-collected plant material. The structures of the new compounds 2-5 and 9 were determined on the basis of spectroscopic data interpretation, and the relative configuration of 6 was confirmed using X-ray crystallography. Compounds 4-6 and the methyl ester, 6a, exhibited broad cytotoxic activity when tested against a panel of human tumor cell lines. Dichapetalin A (1) was not active when evaluated in an in vivo hollow fiber assay in the dose range 1-6 mg/kg.

Antineoplastic Agents, Phytogenic↗
PubMed2006

Cytotoxic flavaglines and bisamides from Aglaia edulis.

Two new cyclopenta[b]benzofurans, aglaroxin A 1-O-acetate (2) and 3'-methoxyaglaroxin A 1-O-acetate (3), a new benzo[b]oxepine, 19,20-dehydroedulisone A (4), and five new cyclopenta[bc]benzopyrans, edulirin A (5), edulirin A 10-O-acetate (6), 19,20-dehydroedulirin A (7), isoedulirin A (8), and edulirin B (9), were isolated from the bark of Aglaia edulis, along with one known cyclopenta[b]benzofuran, aglaroxin A (1). Additionally, four new amides, aglamides A-D (10-13), as well as three known compounds, aglalactone, scopoletin, and 5-hydroxy-3,6,7,4'-tetramethoxyflavone, were isolated from the leaves and/or twigs of this species. The structures of the new compounds (2-13) were elucidated by interpretation of their spectroscopic data. All isolates obtained in this study were evaluated for cytotoxicity against both several human cancer cell lines (Lu1, LNCaP, and MCF-7) and a nontumorigenic (HUVEC) cell line. Among these isolates, the cyclopenta[b]benzofurans (1-3) exhibited potent in vitro cytotoxic activity (ED50 range 0.001 to 0.8 microg/mL). Aglaroxin A 1-O-acetate (2) was further evaluated in the in vivo P388 lymphocytic leukemia model, by intraperitoneal injection, but found to be inactive in this model.

Amides↗
PubMed2006

The dental emergency responder: Expanding the scope of dental practice.

BACKGROUND: Natural disasters, the potential for terrorism and weapons-of-mass-destruction events occurring within the continental United States necessitate that all licensed health care providers understand the National Incident Management System and be able to contribute to inoculation, mass casualty assistance and triage care of the populace. CONCLUSIONS: Health care and political leaders constantly revise "all hazard" response plans, using the available health care assets that local, state and federal agencies bring to emergency events. Illinois Public Act 49-409 modifies the scope of dental practice within Illinois to allow for a dental emergency responder (DER). PRACTICE IMPLICATIONS: The DER is a dentist or dental hygienist "acting within the bounds of his or her license when providing care during a declared local, state or national emergency."

Dentists↗
PubMed2005

Activity-guided isolation of cytotoxic constituents from the bark of Aglaia crassinervia collected in Indonesia.

Activity-guided fractionation of a CHCl(3)-soluble partition of the MeOH extract of the bark of Aglaia crassinervia collected in Indonesia led to the isolation of three new glabretal-type triterpenoids, aglaiaglabretols A-C (1-3), as well as nine known compounds, 3-epi-cabraleahydroxylactone (4), cabraleahydroxylactone (5), rocaglaol (6), 2beta,3beta-dihydroxy-5alpha-pregn-17(20)-(E)-16-one, scopoletin, and mixtures of cabraleadiol and epicotillol and of beta-sitosterol and stigmasterol. The structures of compounds 1-3 were determined on the basis of spectroscopic and chemical methods. The structure of aglaiaglabretol A (1) was confirmed by single-crystal X-ray analysis, and the absolute stereochemistry of this isolate was established by the Mosher ester method. The cytotoxic activity of all isolates and several chemical transformation products obtained in the present study was evaluated. The known cyclopenta[b]benzofuran, rocaglaol (6), was found to be significantly active and comparable in potency to the positive controls, paclitaxel and camptothecin. Aglaiaglabretol B (2) was further tested in an in vivo hollow fiber model.

Aglaia↗
PubMed2005

Cucurbitacins and cucurbitane glycosides: structures and biological activities.

The natural cucurbitacins constitute a group of triterpenoid substances which are well-known for their bitterness and toxicity. Structurally, they are characterized by the tetracyclic cucurbitane nucleus skeleton, namely, 19-(10-->9beta)-abeo-10alpha-lanost-5-ene (also known as 9beta-methyl-19-norlanosta-5-ene), with a variety of oxygen substitutions at different positions. According to the characteristics of their structures, cucurbitacins are divided into twelve categories. The biological effects of the cucurbitacins are also covered.

Biological Factors↗
PubMed2005

Cytotoxic constituents of the twigs of Simarouba glauca collected from a plot in Southern Florida.

Activity-guided fractionation of a chloroform-soluble extract of Simarouba glauca twigs collected from a plot in southern Florida, and monitored with a human epidermoid (KB) tumor cell line, afforded six canthin-6-one type alkaloid derivatives, canthin-6-one (1), 2-methoxycanthin-6-one (2), 9-methoxycanthin-6-one (3), 2-hydroxycanthin-6-one (4), 4,5-dimethoxycanthin-6-one (5) and 4,5-dihydroxycanthin-6-one (6), a limonoid, melianodiol (7), an acyclic squalene-type triterpenoid, 14-deacetyleurylene (8), two coumarins, scopoletin (9) and fraxidin (10), and two triglycerides, triolein (11) and trilinolein (12). Among these isolates, compounds 1-4, 7 and 8 exhibited cytotoxic activity against several human cancer cell lines. 14-Deacetyleurylene (8) was selectively active against the Lu1 human lung cancer cell line, but was inactive in an in vivo hollow fiber assay using this same cell type.

Antineoplastic Agents, Phytogenic↗
PubMed2005

Indole alkaloids from the leaves of Philippine Alstonia scholaris.

The first seco-uleine alkaloids, manilamine (1) (18-hydroxy-19,20-dehydro-7,21-seco-uleine) and N4-methyl angustilobine B (2), were isolated from the (pH 5) alkaloid extract of Philippine Alstonia scholaris leaves together with the known indole alkaloids 19,20-(E)-vallesamine (3), angustilobine B N4-oxide (4), 20(S)-tubotaiwine (5), and 6,7-seco-angustilobine B (6). The structure of the alkaloids was established from MS and NMR experiments.

Alstonia↗
PubMed2005

Constituents of the leaves and twigs of Calyptranthes pallens collected from an experimental plot in Southern Florida.

Fractionation of the chloroform-soluble extract of the leaves and twigs of Calyptranthes pallens, collected from an experimental plot in a hardwood forest of southern Florida, using a hormone-dependent human prostate carcinoma (LNCaP) tumor cell line, led to the isolation of a phloroglucinol derivative with a novel carbon skeleton, pallenic acid (1), and a new triterpenoid, 3beta-hydroxy-18alpha,19alpha-urs-20-en-28-oic acid (2). The known compound methylene-bis-aspidinol (3) was selectively active against the human oral epidermoid carcinoma (KB) cell line. Several known compounds of the ellagic acid, lignan, phloroglucinol, sterol, and triterpene types were also obtained in the present investigation.

Antineoplastic Agents, Phytogenic↗
PubMed2005

Cytotoxic constituents from Cratoxylum arborescens.

A new natural xanthone, 1,3-dihydroxy-6,7-dimethoxy-2,8-diprenylxanthone, together with four known compounds, fuscaxanthone C, 1,7-dihydroxyxanthone, 3-geranyloxy-6-methyl-1,8-dihydroxyanthraquinone and 2-geranylemodin were isolated from the stem bark of Cratoxylum arborescens (Vahl) Blume. The structure elucidations were achieved through spectroscopic analyses. Compounds 1 and 5 showed moderate activity against the human small cell lung cancer NCI-H187 cell line with the IC50 values of 3.69 +/- 1.27 microg/mL and 3.08 +/- 0.73 microg/mL, respectively.

Antineoplastic Agents, Phytogenic↗
PubMed2005

Diterpene glycosides from Egletes viscosa.

A phytochemical investigation of the CHCl (3)-soluble extract of the entire plant of Egletes viscosa (Asteraceae), collected in Peru, afforded two new labdane glycosides, 13-hydroxy-7-oxolabda-8,14-diene 13( R)- O-alpha- L-arabinopyranoside and 13-hydroxylabda-7,14-diene 13( R)- O-alpha- L-arabinopyranoside, along with four known compounds. The structures of the new compounds were elucidated by spectroscopic and chemical methods.

Asteraceae↗
PubMed2005

Antitumour activity of 3-chlorodeoxylapachol, a naphthoquinone from Avicennia germinans collected from an experimental plot in southern Florida.

As part of an ongoing collaborative effort to discover new anticancer agents from plants, an extract obtained from the leaves and twigs of Avicennia germinans, collected in a coastal area of southern Florida, was identified as possessing cytotoxic activity in a panel of human cancer cell lines. Fractionation of the petroleum ether partition, using cytotoxicity to guide the fractionation, led to the isolation of 3-chlorodeoxylapachol. The antitumour potential of 3-chlorodeoxylapachol was demonstrated with the in-vivo hollow fibre assay, a model of antitumour activity using human cancer cell-filled fibres implanted into mice. The possibility that this compound is an artefact of the isolation procedure was ruled out by liquid chromatography-mass spectrometry analysis of extracts prepared without the use of chlorinated solvent. In conclusion, 3-chlordeoxylapachol, a secondary metabolite obtained from the chloroform-soluble extract of a mangrove tree, was cytotoxic in a panel of human cancer cells, and active against KB human cancer cells in the murine hollow fibre antitumour model, with selectivity in KB cells for the intravenous site at lower doses, indicating possible metabolic activation.

Antineoplastic Agents↗