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The article present a brief global history of malaria and discusses the history of research in several countries across the globe that investigated the causes and prevention of malaria. A discussion of research on the prevention of malaria which was conducted in 1900 by Italian hygienist Angelo Celli in Italy is presented.

The article discusses an issue regarding the development of a bacterial cell managed by a chemically synthesized genome. It highlights the potential impact of the introduction of novel organisms on ecosystems since these organisms have never been selected or co-evolved with other organisms. It also discusses the physiological genetics and molecular biology.

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Injection of the immuno-modulatory drug α-galactosylceramide into C57BL/6 mice leads to the already known apoptosis of natural killer T (NKT) cells and to thus far undescribed large changes in the leukocyte populations of the liver. These changes are characterized by the recruitment of neutrophils and that of a population of large monocytic cells. The latter cells display the morphological and immunological features of natural suppressor cells. Their recruitment in the liver depends on the presence of NKT cells, most probably through the local release of cytokines and chemokines by activated NKT cells. We discuss the ubiquitous, long-term effects of α-galactosylceramide injection on immuno-pathological processes mediated through the NKT-triggered recruitment of a subset of large macrophages/monocytes. [Copyright &y& Elsevier]

As natural killer T (NKT) cells have been implicated in the regulation of multiple sclerosis (MS), we investigated expression of the Vα24JαQ canonical rearrangement in MS patients during relapses. We observed major changes in the entire blood Vα24+ T-cell repertoire. Seven of the eight patients showed a marked decrease in Vα24+ transcript number and a decrease in the diversity of the Vα24+ T-cell repertoire, with the exception of a few expanded clones. These perturbations, exacerbated in patient MS (A), led to circulating NKT cell defects. [Copyright &y& Elsevier]

There are two competing theories about the interrelationships of craniates: the cyclostome theory assumes that lampreys and hagfishes are a clade, the cyclostomes, whose sister group is the jawed vertebrates (gnathostomes); the vertebrate theory assumes that lampreys and gnathostomes are a clade, the vertebrates, whose sister group is hagfishes. The vertebrate theory is best supported by a number of unique anatomical and physiological characters. Molecular sequence data from 18S and 28S rRNA genes rather support the cyclostome theory, but mtDNA sequence of Myxine glutinosa rather supports the vertebrate theory. Additional molecular data are thus needed to elucidate this three-taxon problem. We determined the complete nucleotide sequence of the mtDNA of the lamprey Lampetra fluviatilis. The mtDNA of L. fluviatilis possesses the same genomic organization as Petromyzon marinus, which validates this gene order as a synapomorphy of lampreys. The mtDNA sequence of L. fluviatilis was used in combination with relevant mtDNA sequences for an approach to the hagfish/lamprey relationships using the maximum-parsimony, neighbor-joining, and maximum-likelihood methods. Although trees compatible with our present knowledge of the phylogeny of craniates can be reconstructed by using the three methods, the data collected do not support the vertebrate or the cyclostome hypothesis. The present data set does not allow the resolution of this three-taxon problem, and new kinds of data, such as nuclear DNA sequences, need to be collected. [ABSTRACT FROM PUBLISHER]

We have cloned the mitochondrial DNA fragment extending from tRNA-Leu to the cytochrome oxiduse subunit I (COI) genes of Branchiostoma lanceolatum, Myxine glutinosa, Lampetra jluviatilis, and Scyliorhinus caniculus and have determined their respective gene sequences and organization. In all four species, this region contains the ND1 and ND2 genes and the genes coding eight tRNAs, namely, tRNA-Ile, -Gin, -Met, -TV, -Ala, -Asn, -Cys, and -Tyr. The gene order is the same in the hagfish, lamprey and dogfish. In the lancelet, the location of the tRNA genes is slightly different. The mitochondrial code of Myxine, Lampetru, and Scyliorhinus is identical to that of vertebrates. The code used by the lancelet is the same with the exception of AGA (a stop codon in vertebrates), which codes for glycine in the lancelet. From the comparison of the four maps with already published ones for other species, we propose that the main features of the craniate mtDNA between the NDI and COI genes were established in the common ancestor to cephalochordates and vertebrates more than 400 MYA. The origin of replication of the lightstrand (Or&L), usually located between the tRNA-Asn and tRNA-Cys genes in vertebrates, was not found in the lancelet, hagfish, or lamprey (kzmpetra). In contrast, it was found in the dogfish. Thus the position of Ori-L was established for the first time in the common ancestor to the Chondrichthyes and Osteichthyes and remained present in all later-emerging vertebrates. [ABSTRACT FROM AUTHOR]