Proteome analysis of separated male and female gametocytes reveals novel sex-specific Plasmodium biology.

Gametocytes, the precursor cells of malaria-parasite gametes, circulate in the blood and are responsible for transmission from host to mosquito vector. The individual proteomes of male and female gametocytes were analyzed using mass spectrometry, following separation by flow sorting of transgenic parasites expressing green fluorescent protein, in a sex-specific manner. Promoter tagging in transgenic parasites confirmed the designation of stage and sex specificity of the proteins.

Generalizability of carry-over effects in the emotional Stroop task.

The emotional Stroop task has been the most widely used task to examine attentional bias to emotionally salient stimuli. In one format of this task, words are presented to participants in a mixed randomized or quasi-randomized sequence. Using a mixed smoking Stroop task, we have previously demonstrated that smokers are slower to respond to words which follow smoking-related words than words which follow neutral words.

A comprehensive survey of the Plasmodium life cycle by genomic, transcriptomic, and proteomic analyses.

Plasmodium berghei and Plasmodium chabaudi are widely used model malaria species. Comparison of their genomes, integrated with proteomic and microarray data, with the genomes of Plasmodium falciparum and Plasmodium yoelii revealed a conserved core of 4500 Plasmodium genes in the central regions of the 14 chromosomes and highlighted genes evolving rapidly because of stage-specific selective pressures. Four strategies for gene expression are apparent during the parasites' life cycle: (i) housekeeping; (ii) host-related; (iii) strategy-specific related to invasion, asexual replication, and sexual development; and (iv) stage-specific.

Cue-provoked craving and nicotine replacement therapy in smoking cessation.

Cue exposure paradigms have been used to examine reactivity to smoking cues. However, it is not known whether cue-provoked craving is associated with smoking cessation outcomes or whether cue reactivity can be attenuated by nicotine replacement therapy (NRT) in clinical samples. Cue-provoked craving ratings and reaction time responses were measured on the 1st day of abstinence among 158 smokers who had been randomized to high-dose nicotine (35 mg) or placebo patch.

Gene expression in Plasmodium berghei ookinetes and early oocysts in a co-culture system with mosquito cells.

Using an in vitro development system for Plasmodium berghei sporogonic stages and microarray technology we examined parasite gene expression during ookinete invasion of Aedes cells and the ensuing oocyst development. A number of genes were found to be differentially expressed. The most prominent class of up-regulated elements corresponded to products involved in protein synthesis and metabolism.

Malaria parasite transmission stages: an update.

The Molecular Approaches to Malaria 2004 meeting provided an opportunity to see the impressive progress in all research fields and in the four years since the previous Molecular Approaches to Malaria meeting, when much of the Plasmodium falciparum genome sequence was already available. Study of the part of the Plasmodium life cycle associated with transmission through the vector, which begins with the commitment of blood-stage forms to sexual development, has been especially fruitful. This success is a result of several reasons including: (i) the availability of the genome sequence; (ii) the availability of good animal models that allow parasite culture and facile in vivo studies of many of the life cycle stages involved in transmission; (iii) the availability of genetic manipulation technologies for the animal models of malaria, as well as P.

Molecular approaches to malaria.

Malaria is a serious health problem in developing countries. With the complete sequencing of the genomes of the parasite and of the mosquito vector, malaria research has entered the post-genome era. In this report we summarize the results and new research avenues presented at a recent meeting held with the aim of developing interdisciplinary approaches to combat this disease.

A Plasmodium berghei reference line that constitutively expresses GFP at a high level throughout the complete life cycle.

Green fluorescent protein (GFP) is a well-established reporter protein for the examination of biological processes. This report describes a recombinant Plasmodium berghei, PbGFPCON, that constitutively expresses GFP in a growth responsive manner in its cytoplasm from a transgene that is integrated into the genome and controlled by the strong promoter from a P. berghei elongation factor-1alpha gene.

The nicotine dependence syndrome scale: a multidimensional measure of nicotine dependence.

We report the development of a new multidimensional questionnaire to measure nicotine dependence, based on Edwards's syndromal conceptualization of dependence. We present three studies. In study 1, we administered the Nicotine Dependence Syndrome Scale (NDSS) to 317 smokers in a smoking cessation study.

Real-time, in vivo analysis of malaria ookinete locomotion and mosquito midgut invasion.

Invasion of the Anopheles mosquito midgut by the Plasmodium ookinete is a critical step in the malaria transmission cycle. We have generated a fluorescent P. berghei transgenic line that expresses GFP in the ookinete and oocyst stages, and used it to perform the first real-time analysis of midgut invasion in the living mosquito as well as in explanted intact midguts whose basolateral plasma membranes were vitally stained.

Negative affect and smoking lapses: a prospective analysis.

Relapse is a central problem in smoking treatment. Data collected at the time of relapse episodes indicate that stress and negative affect (NA) promote relapse, but retrospective data are potentially biased. The authors performed a prospective analysis of stress and NA prior to initial lapses in smokers (N = 215).

Complement-like protein TEP1 is a determinant of vectorial capacity in the malaria vector Anopheles gambiae.

Anopheles mosquitoes are major vectors of human malaria in Africa. Large variation exists in the ability of mosquitoes to serve as vectors and to transmit malaria parasites, but the molecular mechanisms that determine vectorial capacity remain poorly understood. We report that the hemocyte-specific complement-like protein TEP1 from the mosquito Anopheles gambiae binds to and mediates killing of midgut stages of the rodent malaria parasite Plasmodium berghei.

PTRAMP; a conserved Plasmodium thrombospondin-related apical merozoite protein.

A gene encoding a 352 amino acid protein with a putative signal sequence, transmembrane domain and thrombospondin structural homology repeat was identified in the genome of the human malaria parasite, Plasmodium falciparum and the rodent malaria parasite, Plasmodium berghei. The protein localises in the apical organelles of P. falciparum and P.

Gene targeting demonstrates that the Plasmodium berghei subtilisin PbSUB2 is essential for red cell invasion and reveals spontaneous genetic recombination events.

The Plasmodium merozoite proteases involved in the crucial process of erythrocyte invasion are promising targets for novel malaria control strategies. We report here the characterization of the subtilisin-like protease SUB2 from the rodent parasites Plasmodium berghei and Plasmodium yoelii, leading the way to in vivo functional studies of this enzyme. The kinetics of expression and subcellular localization imply a central role for SUB2 in erythrocyte invasion.

Malaria parasites lacking eef1a have a normal S/M phase yet grow more slowly due to a longer G1 phase.

Eukaryotic elongation factor 1A (eEF1A) plays a central role in protein synthesis, cell growth and morphology. Malaria parasites possess two identical genes encoding eEF1A (eef1aa and eef1ab). Using pbeef1a-Plasmodium berghei mutants that lack an eEF1a gene, we demonstrate that the level of eEF1A production affects the proliferation of blood stages and parasite fitness.

The role of constraints in expert memory.

A great deal of research has been devoted to developing process models of expert memory. However, K. J.

Smoking topography: reliability and validity in dependent smokers.

Data from two studies were analyzed to determine whether smoking through the mouthpiece of a topography unit yields consistent measures over time and to verify that smoking through a mouthpiece results in a similar degree of smoke exposure as conventional smoking. In both studies, subjects smoked their usual brand of cigarette ad libitum. In study A, subjects (n=7) smoked through a mouthpiece on 4 separate experimental days.

Attentional shifts to smoking cues in smokers.

Aims: Many theories of addiction assume that responses to drug cues maintain drug use and precipitate relapse. There is evidence that measures derived from experimental cognitive psychology yield important information about cue reactivity. We used a pictorial version of the visual probe task to evaluate: (i) whether minimally deprived smokers attend differentially to smoking cues (attentional bias); (ii) whether this bias is related to self-reported craving and dependence; and (iii) whether it predicted outcome in a subsequent cessation attempt.

Attentional bias predicts outcome in smoking cessation.

Most attempts to quit smoking end in failure, with many quitters relapsing in the first few days. Responses to smoking-related cues may precipitate relapse. A modified emotional Stroop task-which measures the extent to which smoking-related words disrupt performance on a reaction time (RT) task-was used to index the distracting effects of smoking-related cues.

BRIEF REPORT.

The emotional Stroop task has been widely used to examine attentional bias in a variety of psychological disorders. In one format of this task, words are presented to participants in a mixed randomised or quasi-randomised sequence. We present data from two independent studies involving smokers, the results of which show that words appearing after smoking-related items in the mixed sequence are responded to more slowly than words appearing after neutral items.

Symptoms and lung function in health care personnel exposed to glutaraldehyde.

Background: Glutaraldehyde is widely used as a disinfectant for endoscopic equipment. The aim of this study was to investigate work practices and glutaraldehyde exposure in relation to symptoms and lung function.

Methods: A questionnaire was administered to 76 nurses.

Visuospatial abilities of chess players.

The extent to which the acquisition of expertise in knowledge-rich domains, such as chess, can be influenced by general individual characteristics, such as intelligence, has remained unclear. Some previous studies with children have documented significant correlations between chess skill and performance on some psychometric tests, such as performance IQ. However, we found no evidence for a correlation between chess skill and visual memory ability in a group of adult chess players (N = 36, age = 28.

Analysis of the Plasmodium falciparum proteome by high-accuracy mass spectrometry.

The annotated genomes of organisms define a 'blueprint' of their possible gene products. Post-genome analyses attempt to confirm and modify the annotation and impose a sense of the spatial, temporal and developmental usage of genetic information by the organism. Here we describe a large-scale, high-accuracy (average deviation less than 0.