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Female Aedes aegypti mosquitoes infect hundreds of millions of people each year with dangerous viral pathogens including dengue, yellow fever, Zika, and chikungunya. Progress in understanding the biology of this insect, and developing tools to fight it, has been slowed by the lack of a high-quality genome assembly. Here we combine diverse genome technologies to produce AaegL5, a dramatically improved and annotated assembly, and demonstrate how it accelerates mosquito science and control. We anchored the physical and cytogenetic maps, resolved the size and composition of the elusive sex-determining “M locus”, significantly increased the known members of the glutathione-S-transferase genes important for insecticide resistance, and doubled the number of chemosensory ionotropic receptors that guide mosquitoes to human hosts and egg-laying sites. Using high-resolution QTL and population genomic analyses, we mapped new candidates for dengue vector competence and insecticide resistance. We predict that AaegL5 will catalyse new biological insights and intervention strategies to fight this deadly arboviral vector.

Atopic eczema is a common health problem in children. The prevalence has increased in the past decades. Besides a genetic predisposition, lifestyle factors, dietary habits and indoor environments are thought to be related to its high prevalence. A cross-sectional questionnaire study was carried out in 2011 in the Wuhan area to study associations between home environments and children’s health. The questionnaires were replied to by parents of 2193 children 1–8 years old and the response rate was 91.4% (2193/2400). The results show: (1) The prevalence of “eczema symptom ever that lasted for 6 months” was 23.2%; “eczema symptom in the last 12 months” 7.4% and “awake at night due to itchy rash” 3.4%. (2) Risk factors: Closer to business area (AOR 1.4), moisture related problems (AOR 1.3–2.2), moldy and stuffy odor perception (AOR 1.5), mice observed (AOR 1.8), pet keeping (AOR 1.3), exposure to environmental tobacco smoke (AOR 1.3) and incense (AOR 1.8) were significant risk factors for atopic eczema symptoms ever. Living in an apartment, compared to single family house, was related to more eczema symptom in the last 12 months. Damp clothing/bed sheets and perception of stuffy odor were risk factors for both “eczema symptom in the last 12 months” and “awake due to itchy rash (severe eczema)”. The odds ratio of mice observed for severe eczema was 3.1 (95% CI: 1.4–6.7). It suggests that urbanization, life style and dampness problems at home were significant risk factors for eczema symptoms among children in Wuhan, China.

Background Rett Syndrome (RTT) is a neurodevelopmental disease caused by the disruption of the MECP2 gene. Several mouse models of RTT have been developed with Mecp2 disruptions. Although the mouse models are widely used in RTT research, results obtained need to be validated in other species. Therefore, we performed these studies to characterize phenotypes of a novel Mecp2−/Y rat model and compared them with the Mecp2tm1.1Bird mouse model of RTT. Methods RTT-like phenotypes were systematically studied and compared between Mecp2−/Y rats and Mecp2−/Y mice. In-cage conditions of the rats were monitored. Grip strength and spontaneous locomotion were used to evaluate the motor function. Three-chamber test was performed to show autism-type behaviors. Breathing activity was recorded with the plethysmograph. Individual neurons in the locus coeruleus (LC) were studied in the whole-cell current clamp. The lifespan of the rats was determined with their survival time. Results Mecp2−/Y rats displayed growth retardation, malocclusion, and lack of movements, while hindlimb clasping was not seen. They had weaker forelimb grip strength and a lower rate of locomotion than the WT littermates. Defects in social interaction with other rats were obvious. Breathing frequency variation and apnea in the null rats were significantly higher than in the WT. LC neurons in the null rats showed excessive firing activity. A half of the null rats died in 2 months. Most of the RTT-like symptoms were comparable to those seen in Mecp2−/Y mice, while some appeared more or less severe. The findings that most RTT-like symptoms exist in the rat model with moderate variations and differences from the mouse models support the usefulness of both Mecp2−/Y rodent models. Conclusions The novel Mecp2−/Y rat model recapitulated numerous RTT-like symptoms as Mecp2−/Y mouse models did, which makes it a valuable alternative model in the RTT studies when the body size matters.

Background Rett syndrome (RTT) is a neurodevelopmental disorder caused mostly by disruptions in the MECP2 gene. MECP2-null mice show imbalances in neuronal excitability and synaptic communications. Several previous studies indicate that augmenting synaptic GABA receptors (GABAARs) can alleviate RTT-like symptoms in mice. In addition to the synaptic GABAARs, there is a group of GABAARs found outside the synaptic cleft with the capability to produce sustained inhibition, which may be potential therapeutic targets for the control of neuronal excitability in RTT. Methods Wild-type and MECP2-null mice were randomly divided into four groups, receiving the extrasynaptic GABAAR agonist 4,5,6,7-tetrahydroisoxazolo[5,4-c]pyridin-3-ol hydrochloride (THIP) and vehicle control, respectively. Low-dose THIP was administered to neonatal mice through lactation. RTT-like symptoms including lifespan, breathing, motor function, and social behaviors were studied when mice became mature. Changes in neuronal excitability and norepinephrine biosynthesis enzyme expression were studied in electrophysiology and molecular biology. Results With no evident sedation and other adverse side effects, early-life exposure to THIP extended the lifespan, alleviated breathing abnormalities, enhanced motor function, and improved social behaviors of MECP2-null mice. Such beneficial effects were associated with stabilization of locus coeruleus neuronal excitability and improvement of norepinephrine biosynthesis enzyme expression. Conclusions THIP treatment in early lives might be a therapeutic approach to RTT-like symptoms in MECP2-null mice and perhaps in people with RTT as well.

Background This retrospective study evaluated the utility and safety of surgical lung biopsy (SLB) in cancer patients with acute respiratory distress syndrome (ARDS). Methods All cases of critically ill patients with cancer and diagnosed with ARDS who underwent SLB in a tertiary care hospital from January 2002 to July 2009 were reviewed. Clinical data including patient baseline characteristics, surgical complications, pathological findings, treatment alterations, and survival outcomes were retrospectively collected and analyzed. Results A total of 16 critically ill patients with cancer diagnosed with ARDS who underwent SLB were enrolled. The meantime from ARDS onset to SLB was 3.0 ± 1.5 days. All SLB specimens offered a pathological diagnosis, and specific diagnoses were made in 9 of 16 patients. Biopsy findings resulted in a change in therapy in 11 of 16 patients. Overall, the SLB surgical complication rate was 19% (3/16). SLB did not directly cause the observed operative mortality. The ICU mortality rate was 38% (6/16). Patients who switched therapies after SLB had a trend toward decreased mortality than patients without a change in therapy (27% versus 60%; P = 0.299). Conclusions In selected critically ill cancer patients with ARDS, SLB had a high diagnostic yield rate and an acceptable surgical complication rate.

Background Fusarochromanone (FC101) is a small molecule fungal metabolite with a host of interesting biological functions, including very potent anti-angiogenic and direct anti-cancer activity. Results Herein, we report that FC101 exhibits very potent in-vitro growth inhibitory effects (IC50 ranging from 10nM-2.5 μM) against HaCat (pre-malignant skin), P9-WT (malignant skin), MCF-7 (low malignant breast), MDA-231 (malignant breast), SV-HUC (premalignant bladder), UM-UC14 (malignant bladder), and PC3 (malignant prostate) in a time-course and dose-dependent manner, with the UM-UC14 cells being the most sensitive. FC101 induces apoptosis and an increase in proportion of cells in the sub-G1 phase in both HaCat and P9-WT cell lines as evidenced by cell cycle profile analysis. In a mouse xenograft SCC tumor model, FC101 was well tolerated, non-toxic, and achieved a 30% reduction in tumor size at a dose of 8 mg/kg/day. FC101 is also a potent anti-angiogenenic agent. At nanomolar doses, FC101 inhibits the vascular endothelial growth factor-A (VEGF-A)-mediated proliferation of endothelial cells. Conclusions Our data presented here indicates that FC101 is an excellent lead candidate for a small molecule anti-cancer agent that simultaneously affects angiogenesis signaling, cancer signal transduction, and apoptosis. Further understanding of the underlying FC101’s molecular mechanism may lead to the design of novel targeted and selective therapeutics, both of which are pursued targets in cancer drug discovery.

Background Staphylococcus epidermidis (SE) has emerged as one of the most important causes of nosocomial infections. The SaeRS two-component signal transduction system (TCS) influences virulence and biofilm formation in Staphylococcus aureus. The deletion of saeR in S. epidermidis results in impaired anaerobic growth and decreased nitrate utilization. However, the regulatory function of SaeRS on biofilm formation and autolysis in S. epidermidis remains unclear. Results The saeRS genes of SE1457 were deleted by homologous recombination. The saeRS deletion mutant, SE1457ΔsaeRS, exhibited increased biofilm formation that was disturbed more severely (a 4-fold reduction) by DNase I treatment compared to SE1457 and the complementation strain SE1457saec. Compared to SE1457 and SE1457saec, SE1457ΔsaeRS showed increased Triton X-100-induced autolysis (approximately 3-fold) and decreased cell viability in planktonic/biofilm states; further, SE1457ΔsaeRS also released more extracellular DNA (eDNA) in the biofilms. Correlated with the increased autolysis phenotype, the transcription of autolysis-related genes, such as atlE and aae, was increased in SE1457ΔsaeRS. Whereas the expression of accumulation-associated protein was up-regulated by 1.8-fold in 1457ΔsaeRS, the expression of an N-acetylglucosaminyl transferase enzyme (encoded by icaA) critical for polysaccharide intercellular adhesin (PIA) synthesis was not affected by the deletion of saeRS. Conclusions Deletion of saeRS in S. epidermidis resulted in an increase in biofilm-forming ability, which was associated with increased eDNA release and up-regulated Aap expression. The increased eDNA release from SE1457ΔsaeRS was associated with increased bacterial autolysis and decreased bacterial cell viability in the planktonic/biofilm states.

BackgroundVascular endothelial growth factor (VEGF) and its receptor, VEGFR-2 (Flk-1/KDR), play a key role in tumor angiogenesis. Blocking the VEGF-VEGFR-2 pathway may inhibit tumor growth. Here, we used human VEGFR-2 as a model antigen to explore the feasibility of immunotherapy with a plasmid DNA vaccine based on a xenogeneic homologue of this receptor.MethodsThe protective effects and therapeutic anti-tumor immunity mediated by the DNA vaccine were investigated in mouse models. Anti-angiogenesis effects were detected by immunohistochemical staining and the alginate-encapsulate tumor cell assay. The mechanism of action of the DNA vaccine was primarily explored by detection of auto-antibodies and CTL activity.ResultsThe DNA vaccine elicited a strong, protective and therapeutic anti-tumor immunity through an anti-angiogenesis mechanism in mouse models, mediated by the stimulation of an antigen-specific response against mFlk-1.ConclusionOur study shows that a DNA vaccine based on a xenogeneic homologue plasmid DNA induced autoimmunity against VEGFR-2, resulting in inhibition of tumor growth. Such vaccines may be clinically relevant for cancer immunotherapy.