Vectors for P element-mediated gene transfer in Drosophila.

We have constructed and tested several new vectors for P element-mediated gene transfer. These vectors contain restriction sites for cloning a wide variety of DNA fragments within a small, non-autonomous P element and can be used to efficiently transduce microinjected DNA sequences into the germ line chromosomes of D. melanogaster. The P element in one vector also carries the rosy gene which serves as an easily scored marker to facilitate the transfer of DNA fragments that do not themselves confer a recognizable phenotype. The failure of certain P element constructs to function as vectors suggests that P element sequences, in addition to the 31 bp inverse terminal repeats, are required in cis for transposition. Moreover, removal of the first 38 bp of the autonomous 2.9 kb P element appears to destroy its ability to provide a trans-acting factor (s) required for the transposition of non-autonomous P elements. Finally, we describe a genomic sequence arrangement that apparently arose by the transposition of a 54 kb composite P element from a tetramer plasmid.     

Unusual properties of genomic DNA molecules spanning the euchromatic-heterochromatic junction of a Drosophila minichromosome.

While investigating the copy number of minichromosome Dp(1;f)1187 sequences in the polyploid chromosomes of ovarian nurse and follicle cells of Drosophila melanogaster we discovered that restriction fragments spanning the euchromatic-heterochromatic junction of the chromosome and extending into peri-centromeric sequences had the unusual property of being selectively resistant to transfer out of agarose gels during Southern blotting, leading to systematic reductions in Dp1187-specific hybridization signals. This property originated from the peri-centromeric sequences contained on the junction fragments and was persistently associated with Dp1187 DNA, despite attempts to ameliorate the effect by altering experimental protocols. Transfer inhibition was unlikely to be caused by an inherent physical property of repetitive DNA sequences since, in contrast to genomic DNA, cloned restriction fragments spanning the euchromatic-heterochromatic junction and containing repetitive sequences transferred normally. Finally, the degree of inhibition could be suppressed by the addition of a Y chromosome to the genotype. On the basis of these observations and the fact that peri-centromeric regions of most eukaryotic chromosomes are associated with cytologically and genetically defined heterochromatin, we propose that peri-centromeric sequences of Dp1187 that are incorporated into heterochromatin in vivo retain some component of heterochromatic structure during DNA isolation, perhaps a tightly bound protein or DNA modification, which subsequently causes the unorthodox properties observed in vitro.     

Fascioloides magna (Bassi, 1875) in feral swine from southern Texas.

Between 1971 and 1975, Fascioloides magna was found in 46 of 67 (69%) feral swine (Sus scrofa) in southern Texas. Flukes were recovered from swine in areas where F. magna commonly has been recovered from white-tailed deer and cattle. One to 12 flukes were recovered from each infected animal. Their presence was indicated by black hematin pigment on the liver and various other internal organs. Eggs were not detected in the gallbladder or feces of infected animals although mature flukes and eggs were recovered in the livers suggesting that, like cattle, feral swine can be infected but are aberrant hosts for the parasite and do not disseminate eggs.     

Polyploidization and Cell Fusion Contribute to Wound Healing in the Adult Drosophila Epithelium

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IL-11 and IL-11Rα immunolocalisation at primate implantation sites supports a role for IL-11 in placentation and fetal development

Embryo implantation, endometrial stromal cell decidualization and formation of a functional placenta are critical processes in the establishment and maintenance of pregnancy. Interleukin (IL)-11 signalling is essential for adequate decidualization in the mouse uterus and IL-11 promotes decidualization in the human. IL-11 action is mediated via binding to the specific IL-11 receptor α (IL-11Rα). The present study examined immunoreactive IL-11 and IL-11Rα in cycling rhesus monkey endometrium, at implantation sites in cynomolgus and rhesus monkeys and in human first trimester decidua and defined distinct spatial and temporal patterns. In cycling rhesus monkey endometrium, IL-11 and IL-11Rα increased in both basalis and functionalis regions during the secretory compared with the proliferative phase, with changing cellular locations in luminal and glandular epithelium and stroma. The patterns were similar overall to those previously described in human endometrium. Differences were seen in immunostaining during implantation in cynomologus and rhesus monkey. In the cynomolgus, very little staining for IL-11 or IL-11Rα was seen in syncytio- and cyto-trophoblast cells in the villi between days 12 and 150 of pregnancy although there was moderate staining in cytotrophoblast in the shell between days 12 and 17 and in subpopulations of cytotrophoblast cells invading the arteries at day 17. By contrast in the rhesus monkey between days 24 and 35 of pregnancy and in human first trimester placenta, cyto- and syncytio-trophoblast in the villi but not cytotrophoblast in the shell were positively stained. The most intense staining for both IL-11 and IL-11Rα was present within the decidua in the maternal component of implantation sites in all three primates but moderate staining was also present in maternal vascular smooth muscle and glands perivascular cells and epithelial plaques. These results are consistent with a role for IL-11 both during decidualization and placentation in primates.     

Accelerated hand bone mineral density loss is associated with progressive joint damage in hands and feet in recent-onset rheumatoid arthritis

Introduction

To investigate whether accelerated hand bone mineral density (BMD) loss is associated with progressive joint damage in hands and feet in the first year of rheumatoid arthritis (RA) and whether it is an independent predictor of subsequent progressive total joint damage after 4 years.

Methods

In 256 recent-onset RA patients, baseline and 1-year hand BMD was measured in metacarpals 2-4 by digital X-ray radiogrammetry. Joint damage in hands and feet were scored in random order according to the Sharp-van der Heijde method at baseline and yearly up to 4 years.

Results

68% of the patients had accelerated hand BMD loss (>-0.003 g/cm²) in the first year of RA. Hand BMD loss was associated with progressive joint damage after 1 year both in hands and feet with odds ratios (OR) (95% confidence intervals [CI]) of 5.3 (1.3-20.9) and 3.1 (1.0-9.7). In univariate analysis, hand BMD loss in the first year was a predictor of subsequent progressive total joint damage after 4 years with an OR (95% CI) of 3.1 (1.3-7.6). Multivariate analysis showed that only progressive joint damage in the first year and anti-citrullinated protein antibody positivity were independent predictors of long-term progressive joint damage.

Conclusions

In the first year of RA, accelerated hand BMD loss is associated with progressive joint damage in both hands and feet. Hand BMD loss in the first year of recent-onset RA predicts subsequent progressive total joint damage, however not independent of progressive joint damage in the first year.     

An overview of malaria transmission from the perspective of Amazon Anopheles vectors

In the Americas, areas with a high risk of malaria transmission are mainly located in the Amazon Forest, which extends across nine countries. One keystone step to understanding the Plasmodium life cycle in Anopheles species from the Amazon Region is to obtain experimentally infected mosquito vectors. Several attempts to colonise Ano- pheles species have been conducted, but with only short-lived success or no success at all. In this review, we review the literature on malaria transmission from the perspective of its Amazon vectors. Currently, it is possible to develop experimental Plasmodium vivax infection of the colonised and field-captured vectors in laboratories located close to Amazonian endemic areas. We are also reviewing studies related to the immune response to P. vivax infection of Anopheles aquasalis, a coastal mosquito species. Finally, we discuss the importance of the modulation of Plasmodium infection by the vector microbiota and also consider the anopheline genomes. The establishment of experimental mosquito infections with Plasmodium falciparum, Plasmodium yoelii and Plasmodium berghei parasites that could provide interesting models for studying malaria in the Amazonian scenario is important. Understanding the molecular mechanisms involved in the development of the parasites in New World vectors is crucial in order to better determine the interaction process and vectorial competence.