Jeffrey A. Hughes

Household sanitation in Kumasi, Ghana: A description of current practices, attitudes, and perceptions

Abstract Over 1200 households in Kumasi, Ghana were interviewed in 1989 about their current sanitation practices, perceptions of existing sanitation conditions, expenditures, and their knowledge of improved sanitation options. The results of the survey and related research revealed an appalling and, from a public health perspective, dangerous situation. Households were generating about 25,000 cubic meters of waste per month, but only about 10% of it was removed from the city. The remaining 90% was left in the urban environment. In aggregate, households were spending about US

Radiolabeling of Methylphosphonate and Phosphorothioate Oligonucleotides and Evaluation of Their Transport in Everted Rat Jejunum Sacs

75,000 per month to use the existing sanitation system (about 75% of which was spent for the use of public latrines). People in Kumasi were only spending about US

Household demand for improved sanitation services in Kumasi, Ghana: A contingent valuation study

1.50 per capita annually for sanitation services, and, correspondingly, were getting very poor service. Households were quite open to the idea of simple, low-cost, on-site solutions to their sanitation problems.

Household demand for improved sanitation services : a case study of Kumasi, Ghana

AbstractPurpose. The therapeutic use of antisense oligonucleotides will likely involve their administration over protracted periods of time. The oral route of drug dosing offers many advantages over other possible routes when chronic drug administration is necessary. However, little is known about the potential for oligonucleotide uptake from the gastrointestinal tract. This issue is addressed in the current work. Methods. We have developed a simple procedure for radiolabeling oligonucleotides by reductive alkylation with 14C-formaldehyde. We have utilized this approach, as well as 5′ addition of fluorophores, to prepare labeled methylphosphonate and phosphorothioate oligonucleotides for use in intestinal transport studies. An everted rat gut sac model was employed to compare the transport of oligonucleotides to that of model compounds whose permeation properties are better understood. Results. We demonstrate that both methylphosphonate and phosphorothioate oligonucleotides are passively transported across the intestinal epithelium, probably by a paracellular route. The rates of transport for both types of oligonucleotides were similar, and were significantly greater than that of the very high MW polymer blue dextran, but were lower than the transport rate of valproic acid, a low MW compound known to have high oral availability. Conclusions. A significant degree of permeation of oligonucleotides across the gastrointestinal epithelium does occur, but it is still unclear whether this is sufficient to permit effective oral administration of oligonucleotides as drugs.