Positive selection drives accelerated evolution of mosquito salivary genes associated with blood-feeding.

The saliva of bloodsucking animals contains dozens to hundreds of proteins that counteract their hosts' haemostasis, inflammation and immunity. It was previously observed that salivary proteins involved in haematophagy are much more divergent in their primary sequence than those of housekeeping function, when comparisons were made between closely related organisms. While this pattern of evolution could result from relaxed selection or drift, it could alternatively be the result of positive selection driven by the intense pressure of the host immune system. We investigated the polymorphism of five different genes associated with blood-feeding in the mosquito Anopheles gambiae and obtained evidence in four genes for sites with signatures of positive selection. These results add salivary gland genes from bloodsucking arthropods to the small list of genes driven by positive selection.

Epidemiological features and risk factors of Salmonella gastroenteritis in children resident in Ho Chi Minh City, Vietnam.

Non-typhoidal Salmonella are an important but poorly characterized cause of paediatric diarrhoea in developing countries. We conducted a hospital-based case-control study in children aged <5 years in Ho Chi Minh City to define the epidemiology and examine risk factors associated with Salmonella diarrhoeal infections. From 1419 diarrhoea cases and 571 controls enrolled between 2009 and 2010, 77 (5∙4%) diarrhoea cases were stool culture-positive for non-typhoidal Salmonella. Salmonella patients were more likely to be younger than controls (median age 10 and 12 months, respectively) [odds ratio (OR) 0∙97; 95% confidence interval (CI) 0∙94-0∙99], to report a recent diarrhoeal contact (8∙1% cases, 1∙8% controls; OR 5∙98, 95% CI 1∙8-20∙4) and to live in a household with >2 children (cases 20∙8%, controls 10∙2%; OR 2∙32, 95% CI 1∙2-4∙7). Our findings indicate that Salmonella are an important cause of paediatric gastroenteritis in this setting and we suggest that transmission may occur through direct human contact in the home.

Study of the pressures applied by a Chêneau brace for correction of adolescent idiopathic scoliosis.

We performed a study on 32 idiopathic scoliotic patients (30 females, 2 males) treated with a Chêneau brace. Eighteen patients had a single right thoracic curve and 14 had a single right thoracolumbar curve. We used the TekScan system (ClinSeat Type 5315 Sensor, TekScan, Boston MA, USA) to measure pressures at the skin-brace interface, assess the effect of strap tension and analyze the variation of these pressures with position and activity. The TekScan device enabled identification of the pressure areas corresponding to the brace's three loading points. The pressure under the main pad had a greater mean value than the pressure under the two counter-pads. Tightening the straps led to a significant increase in the pressures, whatever the position studied or the curve pattern. Compared with the standing (reference) position, we observed significantly higher pressures during maximal inspiration (p < 0.001) and lower pressures during maximal expiration, in the prone position and after having risen from a lying position, for both thoracic curves (p < 0.001) and thoracolumbar curves (p < 0.01). The pressures for thoracolumbar curves were lower than those for thoracic curves, whatever the position studied and both before and after strap adjustment. For lying positions, lying on the right side produced the greatest increase pressure. Even though the TekScan system does not provide direct information on the correction of spinal curvature, it appears to be a useful tool in the treatment of scoliotic patients. Strap adjustment clearly influences the applied pressures - particularly those on the rib cage. During activity, there is a natural tendency to decrease the pressure; this justifies efforts to maintain strap tensions in general and during day wear in particular.

An insight into the sialotranscriptome of the non-blood feeding Toxorhynchites amboinensis mosquito.

All adult mosquitoes take sugar meals, and most adult females also take blood meals to develop eggs. Salivary glands (SG) of males are thus much smaller and do not contain many of the antihemostatic and antiinflammatory compounds found in females. In the past 5 years, transcriptome analyses have identified nearly 70 different genes expressed in adult female SG. For most of these, no function can be assigned in either blood or sugar feeding. Exceptionally, Toxorhynchites mosquitoes are unusual in that they never feed on blood, and the SG of adults are identical in both sexes. Transcriptome analysis of the adult SG of this mosquito was performed to increase knowledge of the evolution of blood feeding--and to identify polypeptide families associated with sugar feeding--in mosquitoes.

Determination of the influence of the Chêneau brace on quality of life for adolescent with idiopathic scoliosis.

OBJECTIVE: The main objective is to determine the influence of treatment by Chêneau brace on the quality of life (QoL) of adolescents with idiopathic scoliosis. MATERIAL AND METHOD: We used the QoL scale of Climent et al. "the Quality of Life Profile for Spine Deformities" (QLPSD, in which a higher score means a worse QoL) and visual analogue scales (VAS) for pain and for QoL ranging from 0 to 100mm. The study includes 108 subjects divided in three groups, a control group of 32 patients without brace, a full-time treated group (wearing a Chêneau brace 23/24 hours) of 41 patients, and a part-time treated group (wearing the brace during the night only) of 35 patients. RESULTS: The QoL is significantly worse in the full-time treated group than in the group with night treatment and in the group without brace for the psychosocial functioning, the sleep disturbances, the back flexibility (P<0.001), the body image (P<0.01), as well as the overall score (P<0.001). On the other hand, there was no difference for the back pain. Among patients wearing the brace, the girls had an average QLPSD score higher than the boys for the psychosocial functioning, the body image, the overall score (P<0.05) and the back flexibility (P<0.01). Whereas there was no significant difference between the sexes for the sleep disturbances and the back pain. The QoL of patients who wear the brace was significantly correlated with degrees corrected wearing the brace and the patient's satisfaction on his or her health status. However, this correlation was very weak. On the other hand, there was no correlation between the quality of life and the age, the duration of brace treatment or the skeletal maturity (Risser sign). On VAS, the patients without brace have the highest score of QoL, followed the part-time treated patients while the full-time treated patients have the lowest score. CONCLUSION: The wearing of the Chêneau brace involves a significant reduction in the QoL whatever instruments of evaluations of QoL, QLPSD or VAS. The QoL of the full-time treated patients was the lowest followed part-time treated patients while the QoL of the patients without brace was the highest. However, the brace does not influence the back pain in idiopathic scoliosis at teenage.

[Evaluation of the Chêneau brace in adolescent idiopathic scoliosis]. / Evaluation du résultat du corset de Chêneau dans la scoliose idiopathique de l'adolescent.

OBJECTIVE: We aimed to evaluate the Chêneau brace in the orthopedic treatment of adolescent idiopathic scoliosis to better determine the indications under which it could be prescribed. MATERIALS AND METHODS: This was a retrospective study including 63 patients treated by Chêneau brace for adolescent idiopathic scoliosis between 1997 and 2006. The Cobb angles of the curves in the frontal and sagittal planes as well as rotations and rib hump were measured at the beginning of treatment, with the brace, at the end of treatment and 2 years after discontinuing the brace. A variation of+/-10 degrees in angle was selected to judge the results. RESULTS: At the end of the treatment, 25.4% of the curves were improved and 60.3% stabilized, with 14.3% aggravated; 5 patients (7.9%) required surgery. At 2 years, the reduction in angle was 1.8 degrees, on average. The best results were obtained for the lumbar and dorsolumbar curves. A significant improvement was noted for the dorsal curves; the major double curves are not as accessible to the treatment. For curves whose initial angle was less than 30 degrees , an initial reduction of higher than 50% with the brace presented the best improvement at the end of the follow-up. We note a significant reduction of the rib hump but not accompanied by a reduction of rotation. Finally, we note a deleterious effect in the sagittal curves, with a slight flatness of the spinal profile. CONCLUSION: The continuous wearing of the Chêneau brace can stabilize the evolution of adolescent idiopathic scoliosis, apart from the forms with major double curves, which are not as accessible to the treatment. However, the improvement comes at the price of a slight flatness of the curves of the spine in the sagittal plane. The loss of the correction after discontinuing the brace is minor. We emphasize, therefore, the necessity to monitor the sagittal aspect of the spine as well as the possibility of early treatment, strict surveillance and prolonged follow-up.

Comparative genomics of insect juvenile hormone biosynthesis.

The biosynthesis of insect juvenile hormone (JH) and its neuroendocrine control are attractive targets for chemical control of insect pests and vectors of disease. To facilitate the molecular study of JH biosynthesis, we analyzed ESTs from the glands producing JH, the corpora allata (CA) in the cockroach Diploptera punctata, an insect long used as a physiological model species and compared them with ESTs from the CA of the mosquitoes Aedes aegypti and Anopheles albimanus. The predicted genes were analyzed according to their probable functions with the Gene Ontology classification, and compared to Drosophila and Anopheles gambiae genes. A large number of reciprocal matches in the cDNA libraries of cockroach and mosquito CA were found. These matches defined known and suspected enzymes of the JH biosynthetic pathway, but also several proteins associated with signal transduction that might play a role in the modulation of JH synthesis by neuropeptides. The identification in both cockroach and mosquito CA of homologs of the small ligand binding proteins from insects, Takeout/JH binding protein and retinol-binding protein highlights a hitherto unsuspected complexity of metabolite trafficking, perhaps JH precursor trafficking, in these endocrine glands. Furthermore, many reciprocal matches for genes of unknown function may provide a fertile ground for an in-depth study of allatal-specific cell physiology. ESTs are deposited in GenBank under the accession numbers DV 017592-DV 018447 (Diploptera punctata); DR 746432-DV 747949 (Aedes aegypti); and DR 747950-DR 748310 (Anopheles albimanus).

Exploring the sialome of the blood-sucking bug Rhodnius prolixus.

Rhodnius prolixus is a Hemiptera that feeds exclusively on vertebrate blood in all life stages. Its salivary glands produce potent pharmacological substances that counteract host hemostasis, including anti-clotting, anti-platelet, and vasodilatory substances. To obtain a further insight into the salivary biochemical and pharmacological complexity of this insect, a cDNA library was randomly sequenced, and salivary gland homogenates were fractionated by HPLC to obtain aminoterminal sequences of abundantly expressed proteins. Results indicate a remarkable expansion of the lipocalin family in Rhodnius salivary glands, among other protein sequences described. A summary of 31 new full length proteins deducted from their mRNA sequence is described, including several new members of the nitrophorin, triabin, and pallidipin families. The electronic version of the complete tables is available at http://www.ncbi.nlm.nih.gov/projects/vectors/rhodnius_prolixus.

Toward a description of the sialome of the adult female mosquito Aedes aegypti.

To describe the set of mRNA and protein expressed in the salivary glands (sialome) of Aedes aegypti mosquitoes, we randomly sequenced a full-length cDNA library of this insect and performed Edman degradation of PVDF-transferred protein bands from salivary homogenates. We found 238 cDNA clusters which contained those coding for 10 of the 11 proteins found by aminoterminal degradation. All six previously described salivary proteins were found in this library. Full-length sequences of 32 novel cDNA sequences are reported, one of which is the product of a transposable element. Among the 31 novel protein sequences are 4 additional members of the D7 protein family; 4 novel members of the antigen 5 family (a protein family not reported in Aedes); a novel serpin; a novel member of the 30-kDa allergen of Ae. Aegypti; a secreted calreticulin; 2 proteins similar to mammalian angiopoietins; adenosine deaminase; purine hydrolase; lysozyme; a C-type lectin; 3 serine proteases, including one with high similarity to Bombyx prophenoloxidase activating enzyme; 2 proteins related to invertebrate immunity; and several sequences that have no significant matches to known proteins. The possible role of these proteins in blood and sugar feeding by the mosquito is discussed.