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Evaluation of different tissues of Artemisia annua for their nutritional contents and antioxidant potential demonstrated that the leaves and inflorescences had the highest percentage of protein, crude fat and in vitro digestible fractions but the lowest levels of detergent fibres. These tissues also had the highest composition of the major elements as well as manganese and copper. Their relatively high amino acid and vitamin profiles equally reflect a desirable nutritional balance adding to their high antioxidant capacities. Collectively, these high levels of the different nutritional constituents and antioxidant activities coupled with the very low and often negligible levels of inherent anti-nutritive factors, especially in the leaves, which are far below recommended toxic levels, establishes A. annua as a good reservoir of nutrients and antioxidants that might favour its use as a potential herbal tonic by humans or an important supplementary feed additive for livestock production systems.

Demand for new chemotherapies against malaria is increasing as Plasmodium , the causative organism of the disease, has shown a high degree of resistance against most standard anti-malarial drugs. One of the few highly effective compounds is artemisinin, the major sesquiterpene for the production of artemisinin-based combination therapies (ACTs). This antimalarial drug is extracted from the leaves of Artemisia annua , a plant that is mainly cultivated under cool (temperate) climate and high altitudes. The current study examined the possibility of introducing A. annua germplasm into the agricultural landscape of the lowland humid tropics in field experiments and identified promising accessions that are capable of producing high leaf biomass and artemisinin yields. Differences amongst seed origin, planting season and soil moisture availability had highly significant ( P A. annua in the humid tropics. Two non-photoperiodic hybrid lines evaluated in the trials had suitable agronomic potential, including the production of fresh leaf biomass yield in excess of 30 tonnes/ha with up to 1.0975% artemisinin concentration. This study shows that with improved management practices and using the right accessions, there is an inspiring possibility that the cultivation of A. annua can be optimized in the humid tropics for commercial production of the life saving artemisinin drug, which is most needed in these regions where malaria is endemic.

Commercial activities from outer space have largely consisted of satellite communications. Whilst the maritime and land-mobile services can now be regarded as mature, the next growth area is anticipated in the provision of non-safety aeronautical mobile-satellite services, a service which is now poised to expand significantly in an era marked by competition and convergence of communications technologies. This article highlights and analyses pertinent institutional, legal and regulatory issues, describing what the law is, while making recommendations relating to what the current law should become if the rules were changed to accord with good policy.

Presently, Phase III efficacy trials with subunit immune antigens against the human immunodeficiency virus (HIV) infection are occurring in both the USA and some Southeast Asian countries. However, there is no feeling of dèja vu within the scientific community that these studies will demonstrate meaningful protection against HIV infection, perhaps because the immune responses crucial for containment of the virus might not be elicited by this approach. Under this prevailing gloomy setting for international acquired immune deficiency syndrome (AIDS) therapy, RNA interference has been identified as a likely strategy in the understanding that inhibition of HIV replication can be mediated by post-transcriptional gene silencing through the production of double-stranded RNA (dsRNA) nucleotide intermediates. This review briefly explores the role of the nef gene during HIV-1 infection and highlights the expectation that RNA interference might serve as a new sequence-specific therapeutic arsenal in AIDS prevention, and possibly treatment, in the years ahead.

A serological survey of small ruminant brucellosis was conducted in 210 sheep consisting of 98 Yankassa, 51 Uda and 61 Balami breeds and 201 goats consisting of 90 Borno White, 64 Sokoto Red and 47 crossbred breeds from various nomadic and sedentary flocks in Borno and Yobe States in the arid zone of northeastern Nigeria. Ten (4.8%) of 210 sheep, and 12 (6.0%) of 201 goats tested sero-positive using the Rose Bengal Plate Test (RBPT). Results using the Serum Tube Agglutination Test (SAT) which was used to complement the RBPT were generally lower but were comparable with those of the RBPT. Infection rates were generally higher in goats (6.0%) than in sheep (4.8%), but there was no difference between the species with the RBPT, nor in rates (3.3% in sheep and 4.5% in goats) with the SAT ( P = 0.26). There was no significant difference in infection rates amongst different breeds within each species. Breed susceptibility to infection was non-discriminatory. Infection rates were higher in females than males with RBPT in sheep ( ∗ P = 0.012 ) and goats ( ∗ P = 0.026 ). The risk of acquiring brucellar infection, the relative risk ( R e ) was 4.6 times higher in ewes than in rams with RBPT, and 3.1 times higher with SAT. In goats, risk of acquiring infection was 29.8 times higher in females than in males by RBPT and 22.2 times higher by SAT. There was, however, no significant epidemiological sex-linked association in infection rates. Zoonotic and economic implications accruing from small ruminant brucellosis in the two important livestock producing states of Nigeria are far-reaching, with an estimated annual loss in excess of about US$ 3.2 million at the current level of prevalence.

Embryogenic callus formation and growth of somatic embryos of sugarcane ( Saccharum officinarum L.) were followed by electron microscopy in order to investigate the correlation between the morphological sequence of events and some ultrastructural aspects of storage reserve accumulation. Observations of the differentiation symptoms showed that the embryos pass through distinct morphological stages, superficially reminiscent of those in grass zygotic embryos; with structural bipolar embryonic orientation showing distinctively clear embryo axes and scutellum. Histochemical and ultrastructural examinations revealed that both tissues accumulated significant amounts of the major storage reserves which were sequestered in membrane-bound units, though some differences in storage protein accumulation were observed between them at the later stages of embryo development. Taken together, the developmental and ultrastructural implications of these results are of interest since they show that sugarcane somatic embryos can recapitulate events in zygotic embryos and may, probably, have significance in their utility in synthetic seed technology.

Callus growth parameters such as induction frequency, fresh weight and plant regeneration potentials of ten genotypes of African rice ( Oryza glaberrima ) on Murashige and Skoog (MS) basal medium supplemented with organic nutrients and different levels of two auxin sources as well as the morphological pathway of development leading to plantlet regeneration were studied by scanning electron microscopy. Each of the two synthetic auxins tested: 2,4-dichlorophenoxyacetic acid (2,4-D) and 3,6-dichloro- o -anisic acid (dicamba) was found to have appreciably different effects on the callusing ability of the genotypes at different concentrations. Generally, dicamba was observed to stimulate the formation of a mainly greenish, hard and nodular compact callus phenotype which yielded a higher plant regeneration frequency than 2,4-D in most of the genotypes. Sequential electron microscopy of the callus during growth and differentiation demonstrated that different developmental features were present on the surfaces before the eventual initiation of shoot and root primordia. On the basis of the structural data, the histogenetic event is best ascribed to the non-synchronized, independent growth of callus leading to organogenesis of shoot and root meristems.