Plasmodium falciparum: genetic and immunogenic characterisation of the rhoptry neck protein PfRON4.

The Apicomplexan parasites Toxoplasma and Plasmodium, respectively, cause toxoplasmosis and malaria in humans and although they invade different host cells they share largely conserved invasion mechanisms. Plasmodium falciparum merozoite invasion of red blood cells results from a series of co-ordinated events that comprise attachment of the merozoite, its re-orientation, release of the contents of the invasion-related apical organelles (the rhoptries and micronemes) followed by active propulsion of the merozoite into the cell via an actin-myosin motor. During this process, a tight junction between the parasite and red blood cell plasma membranes is formed and recent studies have identified rhoptry neck proteins, including PfRON4, that are specifically associated with the tight junction during invasion.

Ten families of variant genes encoded in subtelomeric regions of multiple chromosomes of Plasmodium chabaudi, a malaria species that undergoes antigenic variation in the laboratory mouse.

The chromosome ends of human malaria parasites harbour many genes encoding proteins that are exported to the surface of infected red cells, often being involved in host-parasite interactions and immune evasion. Unlike other murine malaria parasites Plasmodium chabaudi undergoes antigenic variation during passage in the laboratory mouse and hence is a model suitable for investigation of switching mechanisms. However, little is known about the subtelomeric regions of P.

PlasmoDB: the Plasmodium genome resource. An integrated database providing tools for accessing, analyzing and mapping expression and sequence data (both finished and unfinished).

PlasmoDB (http://PlasmoDB.org) is the official database of the Plasmodium falciparum genome sequencing consortium. This resource incorporates finished and draft genome sequence data and annotation emerging from Plasmodium sequencing projects.

The sequence of a 200 kb portion of a Plasmodium vivax chromosome reveals a high degree of conservation with Plasmodium falciparum chromosome 3.

Within a 199,866 base pair (bp) portion of a Plasmodium vivax chromosome we identified a conserved linkage group consisting of at least 41 genes homologous to Plasmodium falciparum genes located on chromosome 3. There were no P. vivax homologues of the P.

Prediction of many new exons and introns in Plasmodium falciparum chromosome 2.

The current prediction of genes in the Plasmodium falciparum genome database relies upon a limited number of specially developed computer algorithms. We have re-annotated the sequence of chromosome 2 of P. falciparum by a computer-assisted manual analysis, which is described here.

An algorithm to predict 3' intron splice sites in Plasmodium falciparum genomic sequences.

A new algorithm, PfAGSS, for predicting 3' splice sites in Plasmodium falciparum genomic sequences is described. Application of this program to the published P. falciparum chromosome 2 and 3 data suggests that existing programs result in a high error rate in assigning 3' intron boundaries.

Outcome after partial-hospital treatment of severely disturbed adolescents.

Results of a follow-up study of 50 adolescents treated in a day-hospital program are reported. The program admits seriously disturbed adolescents, over two-thirds with a personality diagnosis. Patients are treated in the day hospital for an average of 3 to 9 months.

Megavitamins for minimal brain dysfunction. A placebo-controlled study.

Preliminary to a stimulant comparison study, 31 children with minimal brain dysfunction randomly received either placebo or a megavitamin combination. During a two-week trial, only two children responded so well that stiumlants were not considered necessary; both were in the placebo group. Change scores from pretest to posttest on four blind ratings by teachers and parents did not show a significant difference between the placebo and vitamin groups.

Methylphenidate vs dextroamphetamine vs caffeine in minimal brain dysfunction: controlled comparison by placebo washout design with Bayes' analysis.

Double-blind crossover comparison of methylphenidate hydrochloride, dextroamphetamine sulfate, and caffeine after placebo washout in 29 children with minimal brain dysfunction (MBD) showed on six ratings that methylphenidate and dextroamphetamine were significantly (P less than .05 to P less than .001) better than placebo and caffeine, but not significantly (P less than .

Levoamphetamine vs dextroamphetamine in minimal brain dysfunction. Replication, time response, and differential effect by diagnostic group and family rating.

Double-blind crossover randomized Latin square comparison of placebo, dextroamphetamine, and levoamphetamine in 31 consecutively diagnosed children with minimal brain dysfunction (MBD) replicated a smaller nonrandom study. Both isomers showed significantly more benefit than placebo but were not significantly different from each other. Dextroamphetamine showed a nonsignificant trend of superiority over levoamphetamine.

Caffeine versus methylphenidate and d-amphetamine in minimal brain dysfunction: a double-blind comparison.

The authors compared the efficacy of caffeine, methylphenidate, and d-amphetamine in children with minimal brain dysfunction using a double-blind crossover design. The slight improvement with caffeine was not significantly better than placebo. Both prescription drugs resulted in significant improvement and were significantly superior to caffeine.

Effect of thyroxin upon the thyroid gland and the regeneration and pigmentation of hair in Peromyscus.

1. Thyroxin distended the follicles of the thyroid gland of Peromyscus. 2.