Significant inhibitory impact of dibenzyl trisulfide and extracts of Petiveria alliacea on the activities of major drug-metabolizing enzymes in vitro: An assessment of the potential for medicinal plant-drug interactions.

Dibenzyl trisulfide (DTS) is the major active ingredient expressed in Petiveria alliacea L., a shrub widely used for a range of conditions, such as, arthritis, asthma and cancer. Given its use alone and concomitantly with prescription medicines, we undertook to investigate its impact on the activities of important drug metabolizing enzymes, the cytochromes P450 (CYP), a key family of enzymes involved in many adverse drug reactions. DTS and seven standardized extracts from the plant were assessed for their impact on the activities of CYPs 1A2, 2C19, 2C9, 2D6 and 3A4 on a fluorometric assay. DTS revealed significant impact against the activities of CYPs 1A2, 2C19 and 3A4 with IC50 values of 1.9, 4.0 and 3.2µM, respectively, which are equivalent to known standard inhibitors of these enzymes (furafylline, and tranylcypromine), and the most potent interaction with CYP1A2 displayed irreversible enzyme kinetics. The root extract, drawn with 96% ethanol (containing 2.4% DTS), displayed IC50 values of 5.6, 3.9 and 4.2µg/mL respectively, against the same isoforms, CYPs 1A2, 2C19 and 3A4. These investigations identify DTS as a valuable CYP inhibitor and P. alliacea as a candidate plant worthy of clinical trials to confirm the conclusions that extracts yielding high DTS may lead to clinically relevant drug interactions, whilst extracts yielding low levels of DTS, such as aqueous extracts, are unlikely to cause adverse herb-drug interactions.

The Anti-cancer Activity of Vernonia divaricata Sw against Leukaemia, Breast and Prostate Cancers In Vitro.

BACKGROUND: Vernonia divaricata is one of five endemic Vernonia species of Jamaica. The ethno-medicinal uses of other species have been established, however, scientific validation of this species has not yet been done and as such this paper is aimed at identifying the anti-cancer activity of V divaricata against leukaemia, breast and prostate cancer cell lines. METHODS: Leaves and stems of V divaricata were dried and milled into powder. The crude hexane and methanol extracts of the leaves and stems were obtained and bio-assayed using WST-1 cell proliferation assay against leukaemia, breast and prostate cancer cell lines. RESULTS: The crude hexane and methanol extracts of V divaricata were able to significantly retard the growth of the MCF-7 (breast), HL-60 (leukaemia) and the PC-3 (prostate) cancer cell lines. The crude methanol extract of the stem was the strongest, exhibiting anti-proliferation activity with IC50 values of 10.14, 12.63 and 9.894 µg/ml for the HL-60, MCF-7 and PC-3 cancer cell lines, respectively, with the most potent toward prostate cancer. CONCLUSION: The medicinal use of V divaricata as an anti-cancer agent was corroborated as the crude hexane and methanol extracts demonstrated potent anti-proliferation activity and as such hold potential for further research and development into a drug to prevent or treat various cancers.

In vitro and in vivo anti-cancer effects of tillandsia recurvata (ball moss) from Jamaica.

OBJECTIVE: Tillandsia recurvata, also commonly known as Ball Moss, is endemic to Jamaica and some parts of the Caribbean and South America. The plant, despite being reported to be used in folk medicine, had not previously been evaluated for its anti-cancer potential. The aim of this study was to evaluate the anti-cancer activity ofBall Moss. METHODS: The anti-proliferation activity of the crude methanolic extract of the T recurvata was evaluated in vitro in five different histogenic cancer cell lines (prostate cancer - PC-3, breast cancer Kaposi sarcoma, B-16 melanoma and a B-cell lymphoma from a transgenic mouse strain) using the trypan blue assay. The crude extract was also evaluated in vivo in tumour-bearing mice. Immunohistochemistry staining with Apoptag was used for histology and determination of apoptosis. RESULTS: The crude methanolic extract of T recurvata demonstrated anti-proliferation activity against all the cell lines, killing > 50% of the cells at a concentration of 2.5 microg/ml. Kaposi sarcoma xenograft tumours were inhibited by up to 75% compared to control in the in vivo study (p < 0.05). There was evidence of DNA fragmentation and a decrease in cell viability on histological studies. The methanolic extract showed no toxic effect in the mice at a dose of 200 mg/kg. CONCLUSIONS: Our data suggest that T recurvata has great potential as an anti-cancer agent and that one of its mechanisms of cell kill and tumour inhibition is by the induction of apoptosis.

Developing an export herb industry - The Jamaican Model: a viable and sustainable means of development

An export herb industry would promote and facilitate the production and industrialization of medicinal and other herbs for an export market, which is estimated to be worth US$ 58 billion and growing at 15 percent annually. This will have far-reaching impact on many sectors such as health, agriculture, tourism, manufacturing, finance, foreign affairs and trade. The pursuit of this industry involves R&D, production, industrialization and commrcialization of the selected herbs. Import substitution of approximately US$ 2.5 million is also involved. Jamaica has the ability and sustainable advantages to ensure the success of this project. Several of 120 major medicinal plants in the world can grow here. Jamaica also has a large unemployed rural labour force, which could produce primary and value added products. The public sector will support R&D capacity for this project. The socio-economic benefits are significant and widespread. This represents an opportunity to attract our youth into agriculture and reduce rural poverty. It can minimize the dislocation of small farmers, threatened byliberalization, and removal of preferential free trade of outputs in which they are not likely to develop competitiveness in the medium term. This project will shift labour from producing illegal drugs into the production of high value medicinal herbs. The production and export of herbs will not require production subsidies. This industry will enhance the product and improve the affordability of local health care

Lead pollution and amelioration measures in the community of Frazers Content, St Catherine, Jamaica.

Lead poisoning, especially in children, is a preventable disease. Many children are exposed to this hazard, especially in poor communities, because of a paucity of information on lead poisoning and increasing economic hardships. In 1994, the case of the poor suburban community of Frazers Content, St Catherine, Jamaica, came to the public attention because of the high frequency of hospital admissions, or outpatient treatment, of children for lead poisoning. This paper reviews a Blue Cross of Jamaica-led-initiative aimed at the clean up and education of the Frazers Content community. The following four-pronged approach was employed: environmental and biological sampling and sample analysis, health education, decontamination and community clean up and entrepreneurial activities. The project outputs included: training of 17 community wardens and 22 schoolteachers; the clean up of 64 residences which had lead levels in excess of 500 ppm; the establishment of an entombment site for the contaminated soil in accordance with the Jamaica Natural Resources Conservation Authority and training of residents in entrepreneurial skills, chicken and rabbit rearing and nursery establishment. The paper includes discussion of the lessons learnt and recommendations for future action.

Lead pollution and amelioration measures in the community of Frazers Content, St Catherine, Jamaica

Lead poisoning, especially in children, is a preventable disease. Many children are exposed to this hazard, especially in poor communities, because of a paucity of information on lead poisoning and increasing economic hardships. In 1994, the case of the poor suburban community of Frazers Content, St Catherine, Jamaica, came to the public attention because of the high frequency of hospital admissions, or outpatient treatment, of children for lead poisoning. This paper reviews a Blue Cross of Jamaica-led-initiative aimed at the clean up and education of the Frazers Content community. The following four-pronged approach was employed: environmental and biological sampling and sample analysis, health education, decontamination and community clean up and entrepreneurial activities. The project outputs included: training of 17 community wardens and 22 schoolteachers; the clean up of 64 residences which had lead levels in excess of 500 ppm; the establishment of an entombment site for the contaminated soil in accordance with the Jamaica Natural Resources Conservation Authority and training of residents in entrepreneurial skills, chicken and rabbit rearing and nursery establishment. The paper includes discussion of the lessons learnt and recommendations for future action.

Image Engine: an object-oriented multimedia database for storing, retrieving and sharing medical images and text.

This paper describes Image Engine, an object-oriented, microcomputer-based, multimedia database designed to facilitate the storage and retrieval of digitized biomedical still images, video, and text using inexpensive desktop computers. The current prototype runs on Apple Macintosh computers and allows network database access via peer to peer file sharing protocols. Image Engine supports both free text and controlled vocabulary indexing of multimedia objects. The latter is implemented using the TView thesaurus model developed by the author. The current prototype of Image Engine uses the National Library of Medicine's Medical Subject Headings (MeSH) vocabulary (with UMLS Meta-1 extensions) as its indexing thesaurus.

Bases farmacológicas para o uso de éter venoso em anestesia / Pharmacological basis of intravenous diethyl ether anesthesia

Apresentam-se as bases farmacocinéticas para o emprego do éter a 5% em soluçäo de glicose por via venosa. Descrevem-se os princípios para os cálculos das quantidades a serem administradas, de acordo com os princípios expostos por Brody e desenvolvidos por Lowe para a anestesia quantitativa. A técnica preconizada é descrita com detalhes, quando se utiliza ventilaçäo com oxigênio puro e com misturas de óxido nitroso. As vantagens e as desvantagens säo descritas, ressaltando-se a segurança associada ao baixo custo de sua aplicaçäo

Developing an export herb industry - The Jamaican Model: a viable and sustainable means of development

An export herb industry would promote and facilitate the production and industrialization of medicinal and other herbs for an export market, which is estimated to be worth US$ 58 billion and growing at 15 percent annually. This will have far-reaching impact on many sectors such as health, agriculture, tourism, manufacturing, finance, foreign affairs and trade. The pursuit of this industry involves R&D, production, industrialization and commercialization of the selected herbs. Import substitution of approximately US$ 2.5 million is also involved. Jamaica has the ability and sustainable advantages to ensure the success of this project. Several of 120 major medicinal plants in the world can grow here. Jamaica also has a large unemployed rural labour force, which could produce primary and value added products. The public sector will support R&D capacity for this project. The socio-economic benefits are significant and widespread. This represents an opportunity to attract our youth into agriculture and reduce rural poverty. It can minimize the dislocation of small farmers, threatened byliberalization, and removal of preferential free trade of outputs in which they are not likely to develop competitiveness in the medium term. This project will shift labour from producing illegal drugs into the production of high value medicinal herbs. The production and export of herbs will not require production subsidies. This industry will enhance the product and improve the affordability of local health care (AU)