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choosing recycled products when possible, and so on. Status ought to be determined by how little we damage the earth and not according to affluence and excess consumption. If we can take on board an altruistic ethic towards future generations and other species, our children and grandchildren will not be able to ask "were you one of those who helped to destroy my future?". 1. The third revolution: environment, population and a sustainable world. By Paul Harrison. London: I B Tauris. 1992. Pp 359. £ 16.95. ISBN 1 85043 501 4.
Clearing the air Dangerous levels of atmospheric pollution should be reduced by on traffic and industrial activity, says the European Parliament (see p 1344). But just how effective would such measures be? The answer to this question-and many emergency restrictions
others-can be found in a WHO report on the acute effects of smog on health.l Smog comes in two types. Summer-type smog is made up largely of the products of reactions between hydrocarbons and nitrogen oxides that are stimulated by intense sunlight. Of this mixture of photochemical pollutants, ozone is judged the most biologically-active, since it causes a range of respiratory symptoms and impairs lung function. Winter-type smog occurs when cold weather causes increases in energy consumption and thus emissions from sulphur-containing fossil fuels. Under stagnant weather conditions, sulphur dioxide and suspended particles-the main constituents--are able to combine to form sulphuric acid. Epidemiological studies show that exposure to winter-type smog can increase morbidity in patients with chronic bronchitis and hospital admissions due to respiratory and cardiovascular disorders. The WHO report indicates what severity of symptoms can be expected with different concentrations of pollutant and gives advice on appropriate action to be taken. Such action includes the setting up of public alert systems and prior identification of sensitive individuals. Unfortunately, well-intentioned traffic bans would not be expected to reduce ozone concentrations, says the report, even though the emissions are a major source of ozone precursors-as Greece found when earlier this month Athens remained shrouded in thick smog despite an emergency traffic ban in the city centre. It is estimated that if all the traffic in the Netherlands were brought to a standstill, ozone would be reduced by only about 4%. health of smog episodes. Geneva: World Health (European Series 43). 1992. Pp 74. Sw Fr 14. ISBN 92 890 1306 0.
1. Acute effects
on
Advances in
cancer
Organisation
chemotherapy
The response of advanced ovarian cancer to taxol can be in high dose and together with granulocyte-colony-stimulating factor (G-CSF). Results of a phase II trial reported at the American Society of Clinical Oncology meeting on May 17-19 indicated that such a regimen reduced tumour size by over 50% in half (22/44) the patients treated-a more than 60% improvement over results from published phase I and II trials using standard doses,1-3 said Dr Gisele Sarosy and Dr Eddie Reed of the National Cancer Institute’s Division of Cancer Treatment. Patients received 250 mg/m2 of taxol every three weeks and 10-20 g/kg of G-CSF daily (a phase I trial had shown that taxol produces peripheral neuropathy at 300 mg/m2). In previous studies taxol dosages ranged from 110 to 175 mg/m2 every 21 days. 7 of the 22 patients with at least 50% tumour shrinkage had radiological evidence of complete disappearance of their tumours, 5 patients responded with 25-50% tumour shrinkage, and 17 patients did not respond. 1 patient died from sepsis. Intensity of previous cancer therapy did not impair response to taxol, nor did age. Randomised trials are needed to ensure the validity of these observations. Later this year, NCI will start a large-scale randomised multicentre trial to compare taxol at standard doses with high-dose taxol plus G-CSF. The supply of taxol, which is extracted from the bark of the Pacific yew tree, is limited. Efforts to find other sources of the drug or related compounds have led to the development of Taxotere, a semi-synthetic form derived from yew needles. In the next few months the NCI and Rhone-Poulenc Rorer Inc are expected to start assessing the efficacy of Taxotere in various cancers.
improved by giving the drug
Another malignant disorder for which encouraging preliminary findings were reported at the meeting was hairy-cell leukaemia. Dr Michael R. Grever of NCI reported that deoxycoformycin (DCF), also known as pentostatin, produced higher remission rates and longer relapse-free survival than did interferon-a2a. DCF induced complete remissions lasting at least four weeks in 68% (104/152) of patients, compared with 11% (17/153) of patients treated with interferon-a2a. Total response rates (partial and complete remissions) were 76% for DCF and 58 % for interferon. Of patients who went into complete remission, half (9/17) the interferon patients relapsed between 12 and 43 months, whereas only 7 of 104 DCF patients relapsed after 13 to 37 months. Patients had been randomly assigned to receive DCF or interferon but were allowed to switch to the other treatment if they did not respond to therapy or relapsed. 101 of the 153 patients who initially received interferon switched to DCF, and 8 of the 152 patients randomised to DCF later received interferon. The study also suggested that DCF may compromise the patient’s ability to handle infections, so it may be
appropriate for patients with active infection to be treated with interferon until the infection subsides, said Dr Grever.
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1. McGuire WP, Rowinsky EK, Rosenshein NB, et al. Taxol: a unique antineoplastic agent with significant activity in advanced ovarian epithelial neoplasms. Ann Intern Med 1989; 111: 273-79. 2. Thigpen T, et al. Phase II trial of taxol as second-line therapy for ovarian carcinoma: 3.
Gynecologic Oncology Study Group. ASCO 1990: 156. Einzig Al. Phase II study of taxol in patients with advanced ovarian cancer. AACR 1990: 187.
Clinical freedom The General Medical Council has shown that it can still fight for doctors’ rights to do their utmost for their patients. In one of its vignette debates, which took place on the second day of the Council’s meeting last week, a declaration was made that seemed to be carried against the "better judgment" of some of the senior members. After council members had loudly frustrated a suggestion that the motion should be referred back for committee consideration, the motion was passed that "The Council reiterates the principle that a doctor should always seek to give priority to the investigation and treatment of patients solely on clinical need".
Commercial enterprise for better health? Commercial sales and marketing techniques will be exploited in a trial to be launched later this year aimed at reducing the prevalence of sexually transmitted diseases (STDs) in Cameroon, West Africa. The project, organised by Family Health International (FHI), consists of the promotion of STD treatment kits that contain appropriate antibiotics, condoms, and referral coupons to encourage sexual partners to purchase kits of their own. The kits will be priced so that they are affordable by people on low-incomes yet give enough of a profit margin to encourage pharmacists to stock the product. A similar trial, organised by Population Services International (PSI), increased the availability of condoms. PSI is collaborating with FHI in the new project. The emphasis in this project is on quality rather than quantity. At present, antibiotics are often sold unlabelled and without instructions, and are taken inappropriately. The project this year will concentrate on control of gonorrhoea and chlamydia, but if this project is successful it might be expanded to the control of other diseases, particularly syphilis and genital ulcers. Success of promotion of the kits will be assessed by medical audit, cost-effectiveness research, and consumer research on affordability and availability. Drug effectiveness will be assessed by monitoring the extent of antimicrobial resistance and adverse reactions. Other variables that will be assessed include the extent to which condoms are used to prevent STD spread, the efficacy of the partner-referral coupons, and changes in the population’s knowledge of STD and the ability of the kit stockists to diagnose disease correctly and
prescribe treatment. The Organisation de Coordination pour la Lutte Contre les Endemies en Afrique Centrale (OCEAC), a regional health research agency, is principally responsible for the baseline research and for monitoring and evaluating the project. The project is being funded by USAID.