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Bacteria belonging to the genus Wolbachia are obligatory microendocytobionts that infect a variety of arthropods and a majority of filarial nematode species, where they induce reproductive alterations or establish a mutualistic symbiosis. Although two whole genome sequences of Wolbachia pipientis, for strain wMel from Drosophila melanogaster and strain wBm from Brugia malayi, have been fully completed and six other genome sequencing projects are ongoing (http://www.genomesonline.org/index.cgi?want=Prokaryotic+Ongoin), genetic analyses of these bacteria are still scarce, mainly due to the inability to cultivate them outside of eukaryotic cells. Usually, a large amount of host tissue (a thousand individuals, or about 10 g) is required in order to purify Wolbachia and extract its DNA, which is often recovered in small amounts and contaminated by host cell DNA, thus hindering genomic studies. In this report, we describe an efficient and reliable procedure to representatively amplify the Wolbachia genome by multiple-displacement amplification from limited infected host tissue (0.2 g or 2 x 10(7) cells). We obtained sufficient amounts (8 to 10 microg) of DNA of suitable quality for genomic studies, and we demonstrated that the amplified DNA contained all of the Wolbachia loci targeted. In addition, our data indicated that the genome of strain wRi, an obligatory endosymbiont of Drosophila simulans, shares a similar overall architecture with its relative strain wMel.

Objective: To enable serodiscordant couples to reproduce while minimizing the risk of infecting the female partner and to demonstrate the feasibility of including these couples in an insemination program., Design: Prospective follow-up study., Setting: Ambulatory IUIs., Patient(s): Fifty-six HIV-1-serodiscordant couples with a male infected partner., Intervention(s): Sperm cell separation by the gradient density method followed by the swim-up method, virological detection, and IUI after ovarian stimulation., Main Outcome Measure(s): Pregnancy rate, HIV-1 test, and p24 antigenemia in women., Result(s): Two hundred thirteen IUIs were performed, and 37 pregnancies occurred, resulting in 33 births and 2 ongoing pregnancies. Fifty percent of couples have a child. No women were infected., Conclusion(s): Our study demonstrates the efficiency of an IUI program with prepared and virologically tested spermatozoa in serodiscordant couples with an HIV-1-infected male partner, allowing the couples to have children without transmission of the virus to the female partner.

Herbivores that feed on toxic plants must overcome plant defenses and occasionally may even benefit from them. The current challenge is to understand how herbivores evolve the necessary physiological adaptations and which changes at the molecular level are involved. In this context we studied the leaf beetles genus Chrysochus (Coleoptera, Chrysomelidae). Two species of this genus, C. auratus and C. cobaltinus, feed on plants that contain toxic cardenolides. These beetles not only avoid poisoning by the toxin but also use it for their own defense against predators. All other Chrysochus species feed on plants that are devoid of cardenolides. The most important active principle of cardenolides is their capacity to bind to and thereby block the ubiquitous Na(+)/K(+)-ATPase responsible for maintaining cellular potentials. By analyzing the DNA sequence of the putative ouabain-binding site of the alpha-subunit of the Na(+)/K(+)-ATPase gene of Chrysochus and its close relatives feeding on plants with or without cardenolides, we here trace the evolution of cardenolide insensitivity in this group of beetles. The most interesting difference among the sequences involves the amino acid at position 122. Whereas all species that do not encounter cardenolides have an asparagine in this position, both Chrysochus species that feed on cardenolide plants have a histidine instead. This single amino acid substitution has already been shown to confer cardenolide insensitivity in the monarch butterfly. A mtDNA-based phylogeny corroborates the hypothesis that the asparagine at position 122 of the alpha-subunit of the Na(+)/K(+)-ATPase gene as observed in Drosophila and other insects is the plesiomorphic condition in this group of leaf beetles. The later host-plant switch to cardenolide-containing plants in the common ancestor of C. auratus and C. cobaltinus coincides with the exchange of the asparagine for a histidine in the ouabain binding site.

Evidence for the use of defensive compounds for sexual purposes is scarce, even though sexual selection might have some importance for the evolution of defensive traits. This study investigates the effect of defense-related traits and body size on mating success in two sister species of leaf beetle differing in their type of chemical defense. Oreina gloriosa produces autogenous cardenolides, whereas O. cacaliae sequesters pyrrolizidine alkaloids from its food plant. Larger O. gloriosa males with more toxin or higher toxin concentration had a mating advantage, likely due to direct or indirect female choice. In the laboratory, particular pairings recurred repeatedly in this species, indicating mate fidelity. O. gloriosa females were also subject to sexual selection, possibly by male choice, because larger females and those with higher toxin concentration mated more readily and more often. In O. cacaliae, in contrast, sexual selection for toxicity and body size was not detected, or at best was much weaker. Because toxicity is heritable in O. gloriosa but environment-dependent in O. cacaliae, individuals of the former species could be choosing well-defended partners with "good genes." Our study suggests that sexual selection may contribute to the maintenance of heritable defensive traits.

Use of hormonal replacement therapy after treatment of ovarian or endometrial cancer remains a matter of debate. Novel adjuvant therapies tend to increase the survival of these patients, who are exposed to risk factors of hormonal deficiency subsequent to primary therapy. Therefore, the aims of the present review of literature was to analyse epidemiologic and clinical parameters on behalf on hormonal replacement therapy in this population.

After evaluation of the force necessary for filling of the gall bladder, it seemed to us difficult to admit that the sphincter of Oddi was the only mechanism necessary for filling, which occurs perfectly without this sphincter. This is why our attention was drawn to the possible role of cystic duct circular muscle which has an important neuro-muscular supply and a known peristaltic activity. Studying the anatomical structure of the region, we examined the various routes which may be followed by the bile during filling and emptying. Filling follows a very particular course, like a cork screw, between the wall of the cystic duct and the lower surface of Heisster's value in which the neuro-muscular mechanism is sufficient to ensure peristaltic movements which may pump the bile across Lutken's sphincter into the gall bladder.

Hydrochlorothiazide, tienilic acid, chlorthalidone and indapamide inhibit membrane adenylate cyclase of pigeon erythrocytes in vitro. This effect is related to the action of these substances on the interface between the membranous phospholipids and adenylate cyclase. Indapamide with its strong lipophic properties, has a more specific action on the intracellular regulation of adenylate cyclase. The relationship between the inhibition of adenylate cyclase and the antihypertensive effects of these drugs is discussed.

Cardiazol induces in the Mauthner cell the paroxysmal depolarizing shifts which are characteristic of epilepsia at the neuronal level. The period of depolarizations is preceded and, later, accompanied by an increased transmission at the electrotonic synapses which are established upon this neuron by primary afferent vestibular fibers. Increased excitability of the chemical synapses occurs subsequently.

Measurement of the activity of the sphincter of Oddi by the method of classical manometry did not reveal any significant difference before and after vagotomy. However, the existence after perfusion of residual pressure greater than initial pressure, suggests that a deformity of the duct during perfusion disturbs measurement of the opening of the sphincter. The mechanical properties of the duct were measured in vitro, as a first approximation it was suggested that the error due to a deformity of the duct, might be eliminated using several perfusion rates and calculating for each rate the opening R of the sphincter using the following formula: R equals (Perfusion pressure-Residual pressure) Flow rate. When the opening of the sphincter is calculated in this way, one may observe that vagotomy leads to definite reduction of the resistance of Oddi's sphincter.

The application of a venous tourniquet leads to distension of the distal venous and capillary circulation and a local increase in plasma volume. In the normal subject, plasma volume returns to its initial level within approximately 10 sec of tourniquet release. In subjects affected by cyclical oedema, the local increase in plasma volume persists several minutes after tournique release. Radioactive labelling of plasma proteins shows that this delay is associated with the retention of plasma proteins by the tissues. These proteins are subsequently cleared by lymphatic drainage or diffusion back into veins. These results suggest that the combination of tournique test with the labelling of plasma proteins measures capillary and venous permeability as well as tissue protein clearance kinetics.