Phenolic compounds in date palm cultivars sensitive and resistant toFusarium oxysporum

In date palm (Phoenix dactylifera L.) leaves, the main compounds of the phenolic pool were quercetin and isorhamnetin heterosides, (+)-catechin and (-)-epicatechin. Although previously observed only in date palm fruits, 5-caffeoylshikimic acid (dactylifric acid) and its positional isomers (3-caffeoylshikimic acid and 4-caffeoylshikimic acid) were detected also in the leaves and roots. Quantitative, but not qualitative, differences between cultivars resistant and susceptible toFusarium oxysporum f. sp.albedinis during growth period were observed Acknowledgements: The authors are very grateful to Dr. Janati, Director of SCAS (INRA, Marrakech) for supplying the plant material used in this study. The study was funded by the Programme de Cooperation Franco-Marocaine (Al 473/90) between Cadi Ayyad University (Marrakech, Maroc) and Montpellier II University (France)     

Interferon-α conjugation to human osteogenic sarcoma monoclonal antibody 791T/36

Human lymphoblastoid interferon-alpha (IFN-alpha) has been coupled using N-succinimidyl 3-(2-pyridyldithio) propionate (SPDP) to a murine monoclonal antibody (791T/36) which reacts with antigens expressed on human osteogenic sarcomas. The purified conjugates retain antibody activity as defined by their capacity to compete with binding of fluorescein isothiocyanate-labelled 791T/36 antibody to 791T cells. IFN-alpha-791T/36 antibody conjugates synthesized with 125I-trace-labelled IFN-alpha and 131I-trace-labelled antibody also bound to 791T cells, but not to bladder carcinoma T24 cells. The conjugates also retain the capacity of free IFN to activate natural killer cells in human peripheral blood lymphocytes and show specific localization in human osteogenic sarcoma xenografts developing in immunodeprived mice. These findings establish that conjugates containing IFN linked to a monoclonal antibody reacting with osteogenic sarcoma-associated antigens have potential for targeted immunotherapy and in related investigations with antibody has been shown by gamma camera imaging of patients following infusion of 131I-labelled antibody to localize in primary osteogenic sarcomas.     

A randomised dose ranging study of recombinant tissue plasminogen activator in acute myocardial infarction

To assess the thrombolytic efficacy and the effect on the systemic fibrinolytic system of recombinant tissue plasminogen activator doses of 20 mg, 50 mg, and 100 mg were compared in a randomised study. Tissue plasminogen activator was infused intravenously over 90 minutes in 50 consecutive patients with acute myocardial infarction of four hours'' duration or less; on average the infusion was started 135 minutes (range 20 to 240) after the onset of pain. The affected artery was patent at the end of the 90 minute infusion in 14/17 (82%) of those who received 100 mg, 12/17 (71%) of those who received 50 mg, and 8/16 (50%) of those who received 20 mg. Regardless of dose, reperfusion rates were significantly better for patients treated within two hours of the onset of symptoms (81%) than for those treated in the third and fourth hours (54%). At the end of the infusion serum fibrinogen concentrations fell to 86% of the preinfusion value after 20 mg, 75% after 50 mg, and 63% after 100 mg, and similar dose dependent changes occurred in plasminogen, α₂ anti-plasmin, and fibrinogen and fibrin degradation products. The mean infarct related regional third ejection fraction was 46% for patients with grade 2 or 3 reperfusion and 35% for those with grade 0 or 1. Ventricular fibrillation occurred in six (12%) patients during the infusion of tissue plasminogen activator, but no late ventricular fibrillation occurred. Bleeding was minimal, reocclusion occurred in three patients, and four patients died from cardiac causes.Recombinant tissue plasminogen activator is an effective thrombolytic agent which produces better reperfusion rates after a 50 or 100 mg dose than after a 20 mg dose. The effect on the systemic fibrinolytic system is dose dependent. Successful reperfusion results in improvement of left ventricular function.     

Impact of pyrethroid-impregnated curtains on Phlebotomus papatasi sandflies indoors at Khartoum, Sudan

Laboratory and field investigations were made in an endemic focus of cutaneous leishmaniasis in Khartoum State, Sudan, to evaluate the effects of permethrin-impregnated curtains on the human-biting activity, nocturnal activity and resting behaviour of the vector sandfly Phlebotomus papatasi (Diptera: Psychodidae) indoors. Laboratory bioassays showed that curtains impregnated with 0.5, 1.0 or 1.5 g/m2 permethrin all gave 100% mortality within 24h of exposure of P. papatasi for 3 min. Under natural field conditions, the biting activity indoors and the resting density of P. papatasi were significantly reduced (P<0.001 and P=0.036, respectively) in rooms provided with permethrin-impregnated curtains as compared to control rooms left without curtains or fitted with unimpregnated curtains. No significant difference was found between the numbers of nocturnally active P. papatasi collected in rooms provided with impregnated curtains and rooms left without curtains or provided with unimpregnated curtains (P=0.377). Evidently P. papatasi was not repelled by these doses of permethrin on curtains, but the survival rate of sandflies collected from test rooms provided with permethrin-impregnated curtains was significantly reduced (P=0.036). We conclude that use of permethrin-impregnated curtains may provide a good control method for P. papatasi and other endophilic and/or endophagic sandfly vectors of leishmaniasis.