Field testing of different chemical combinations as odour baits for trapping wild mosquitoes in The Gambia

Odour baited traps have potential use in population surveillance of insect vectors of disease, and in some cases for vector population reduction. Established attractants for human host-seeking mosquitoes include a combination of CO(2) with L-lactic acid and ammonia, on top of which additional candidate compounds are being tested. In this field study in rural Gambia, using Latin square experiments with thorough randomization and replication, we tested nine different leading candidate combinations of chemical odorants for attractiveness to wild mosquitoes including anthropophilic malaria vectors, using modified Mosquito Magnet-X (MM-X) counterflow traps outside experimental huts containing male human sleepers. Highest catches of female mosquitoes, particularly of An. gambiae s.l. and Mansonia species, were obtained by incorporation of tetradecanoic acid. As additional carboxylic acids did not increase the trap catches further, this 'reference blend' (tetradecanoic acid with L-lactic acid, ammonia and CO(2)) was used in subsequent experiments. MM-X traps with this blend caught similar numbers of An. gambiae s.l. and slightly more Mansonia and Culex mosquitoes than a standard CDC light trap, and these numbers were not significantly affected by the presence or absence of human sleepers in the huts. Experiments with CO(2) produced from overnight yeast cultures showed that this organic source was effective in enabling trap attractiveness for all mosquito species, although at a slightly lower efficiency than obtained with use of CO(2) gas cylinders. Although further studies are needed to discover additional chemicals that increase attractiveness, as well as to optimise trap design and CO(2) source for broader practical use, the odour-baited traps described here are safe and effective for sampling host-seeking mosquitoes outdoors and can be incorporated into studies of malaria vector ecology.     

Combination mode of antimalarial drug mefloquine and human serum albumin: Insights from spectroscopic and docking approaches

The interaction between mefloquine (MEF), the antimalarial drug, and human serum albumin (HSA), the main carrier protein in blood circulation, was explored using fluorescence, absorption, and circular dichroism spectroscopic techniques. Quenching of HSA fluorescence with MEF was characterized as static quenching and thus confirmed the complex formation between MEF and HSA. Association constant values for MEF-HSA interaction were found to fall within the range of 3.79-5.73 × 10⁴ M^˗1 at various temperatures (288, 298, and 308 K), which revealed moderate binding affinity. Hydrogen bonds and hydrophobic interactions were predicted to connect MEF and HSA together in the MEF-HSA complex, as deduced from the thermodynamic data (ΔS = +133.52 J mol⁻¹ K⁻¹ and ΔH = +13.09 kJ mol⁻¹) of the binding reaction and molecular docking analysis. Three-dimensional fluorescence spectral analysis pointed out alterations in the microenvironment around aromatic amino acid (tryptophan and tyrosine) residues of HSA consequent to the addition of MEF. Circular dichroic spectra of HSA in the wavelength ranges of 200-250 and 250-300 nm hinted smaller changes in the protein's secondary and tertiary structures, respectively, induced by MEF binding. Noncovalent conjugation of MEF to HSA bettered protein thermostability. Site marker competitive drug displacement results suggested HSA Sudlow's site I as the MEF binding site, which was also supported by molecular docking analysis.     

Super‐beacons: Open‐source probes with spontaneous tuneable blinking compatible with live‐cell super‐resolution microscopy

Localization‐based super‐resolution microscopy relies on the detection of individual molecules cycling between fluorescent and non‐fluorescent states. These transitions are commonly regulated by high‐intensity illumination, imposing constrains to imaging hardware and producing sample photodamage. Here, we propose single‐molecule self‐quenching as a mechanism to generate spontaneous photoswitching. To demonstrate this principle, we developed a new class of DNA‐based open‐source super‐resolution probes named super‐beacons, with photoswitching kinetics that can be tuned structurally, thermally and chemically. The potential of these probes for live‐cell compatible super‐resolution microscopy without high‐illumination or toxic imaging buffers is revealed by imaging interferon inducible transmembrane proteins (IFITMs) at sub‐100 nm resolutions.     

Aroma Profile of Two Populations of Salvia verbenaca Collected from Two Bio‐Geographical Zones from Jordan

The aroma emitted from the different organs of two Salvia verbenaca L. populations from Jordan were extracted by Solid Phase Micro‐Extraction (SPME) and then analyzed by GC/MS. The emission profile of the stem, leaf and sepal samples from the Mediterranean zone (Al‐Salt) was dominated by monoterpene hydrocarbons (68.0 %, 33.7 %, and 42.2 %, respectively). The emission profile of flowering parts including pre‐flowering buds, fully expanded flowers and petals was dominated by oxygenated monoterpenes (58.6 %, 59.3 % and 87.1 %, respectively). The major constituent detected in these organs was trans‐sabinene hydrate acetate (range 14.5 %–87.0 %). On the other hand, samples collected from Irano‐Turanian zone showed different emission patterns. While the stems, leaves and petal emissions were dominated by sesquiterpene hydrocarbons (54.9 %, 76.8 % and 52.6 %, respectively), monoterpene hydrocarbons dominated the emission profiles of the pre‐flowering buds (75.1 %) and fully expanded flowers (73.6 %). Petals emissions were characterized by high concentrations of oxygenated monoterpenes (58.8 %). Notably, trans‐sabinene hydrate dominated most organs emissions except for leaves (range 20.0 %–58.8 %). Principle Component Analysis (PCA) and Cluster Analysis (CA) revealed two different clusters related to the two different geographical zones. The current investigation revealed two ecotypes of S. verbenaca that could result in two different chemotypes. Trans‐sabinene hydrate acetate and trans‐sabinene hydrate are suggested compounds for identifying these two chemotypes.     

Detecting Foci of Malaria Transmission with School Surveys: A Pilot Study in the Gambia

Background

In areas of declining malaria transmission such as in The Gambia, the identification of malaria infected individuals becomes increasingly harder. School surveys may be used to identify foci of malaria transmission in the community.

Methods

The survey was carried out in May–June 2011, before the beginning of the malaria transmission season. Thirty two schools in the Upper River Region of The Gambia were selected with probability proportional to size; in each school approximately 100 children were randomly chosen for inclusion in the study. Each child had a finger prick blood sample collected for the determination of antimalarial antibodies by ELISA, malaria infection by microscopy and PCR, and for haemoglobin measurement. In addition, a simple questionnaire on socio-demographic variables and the use of insecticide-treated bed nets was completed. The cut-off for positivity for antimalarial antibodies was obtained using finite mixture models. The clustered nature of the data was taken into account in the analyses.

Results

A total of 3,277 children were included in the survey. The mean age was 10 years (SD = 2.7) [range 4–21], with males and females evenly distributed. The prevalence of malaria infection as determined by PCR was 13.6% (426/3124) [95% CI = 12.2–16.3] with marked variation between schools (range 3–25%, p<0.001), while the seroprevalence was 7.8% (234/2994) [95%CI = 6.4–9.8] for MSP1₁₉, 11.6% (364/2997) [95%CI = 9.4–14.5] for MSP2, and 20.0% (593/2973) [95% CI = 16.5–23.2) for AMA1. The prevalence of all the three antimalarial antibodies positive was 2.7% (79/2920).

Conclusions

This survey shows that malaria prevalence and seroprevalence before the transmission season were highly heterogeneous.     

The Role of Statins in Prevention and Treatment of Community Acquired Pneumonia: A Systematic Review and Meta-Analysis

Background

Emerging epidemiological evidence suggests that statins may reduce the risk of community-acquired pneumonia (CAP) and its complications.

Purpose

Performed a systematic review to address the role of statins in the prevention or treatment of CAP.

Data Source

Ovid MEDLINE, Cochrane, EMBASE, ISI Web of Science, and Scopus from inception through December 2011 were searched for randomized clinical trials, cohort and case-control studies.

Study Selection

Two authors independently reviewed studies that examined the role of statins in CAP.

Data Extraction

Data about study characteristics, adjusted effect-estimates and quality characteristics was extracted.

Data Synthesis

Eighteen studies corresponding to 21 effect-estimates (eight and 13 of which addressed the preventive and therapeutic roles of statins, respectively) were included. All studies were of good methodological quality. Random-effects meta-analyses of adjusted effect-estimates were used. Statins were associated with a lower risk of CAP, 0.84 (95% CI, 0.74–0.95), I² = 90.5% and a lower short-term mortality in patients with CAP, 0.68 (95% CI, 0.59–0.78), I² = 75.7%. Meta-regression did not identify sources of heterogeneity. A funnel plot suggested publication bias in the treatment group, which was adjusted by a novel regression method with a resultant effect-estimate of 0.85 (95% CI, 0.77–0.93). Sensitivity analyses using the rule-out approach showed that it is unlikely that the results were due to an unmeasured confounder.

Conclusions

Our meta-analysis reveals a beneficial role of statins for the risk of development and mortality associated with CAP. However, the results constitute very low quality evidence as per the GRADE framework due to observational study design, heterogeneity and publication bias.     

Genome Array of Hair Follicle Genes in Lambskin with Different Patterns

Hu sheep lambskin comes from a specific breed of sheep of China. Hu sheep are considered a protected breed by the Chinese government. The hair follicles of these sheep have three types of waves, large, medium, and small. There are only few histological reports of Hu sheep lambskin, and there are no modern molecular or biological studies, so the molecular mechanisms underlying the formation of hair follicles with different patterns are not currently known. The aim of this article was to study the molecular mechanism of the formation of these types of hair follicles in Hu sheep. Histological and microscopic analysis indicated that the number of follicles with small waves was not significantly higher than the number of follicles with large waves (P>0.05). The diameters of primary and secondary small-wave follicles were significantly smaller than those of large-wave follicles (P<0.05; P<0.01). The ratio between the number primary follicles and the number of secondary follicles was significantly higher among small-wave follicles than among large-wave follicles (P<0.05). Differentially expressed genes in the skin tissue were screened using an Agilent gene chip and RT-PCR. Differential expression analysis revealed 3 groups of large waves and small waves; 1067, 2071, and 3879 differentially expressed genes; and 137 genes common to all 3 groups. Differentially expressed genes were classified using gene ontology. They were found to be mainly involved in cell differentiation, proliferation, apoptosis, growth, immune response, and ion transport. RT-PCR results of 4 differentially expressed genes were consistent with gene chip results. Combined with related literature, our results suggest that BMP7, MMP2, SNAI1, SFXN1, CDKNIC, MT3, and POU1F1 may have important effects on the formation of large-wave and small-wave hair follicles. This study may enrich knowledge of hair follicle development, and may identify the genes responsible for the formation of hair follicles with different patterns.     

NF-κB mediates the induction of Fas receptor and Fas ligand by microcystin-LR in HepG2 cells

Microcystin-LR (MC-LR) is the most frequent and most toxic microcystin identified. This natural toxin has multiple features, including inhibitor of protein phosphatases 1 and 2A, inducer of oxidative stress, as well as, tumor initiator and promoter. One unique character of MC-LR is this chemical can accumulate into liver after contacting and lead to severe damage to hepatocytes, such as apoptosis. Fas receptor (Fas) and Fas ligand (FasL) system is a critical signaling system initiating apoptosis. In current study, we explored whether MC-LR could induce Fas and FasL expression in HepG2 cells, a well used in vitro model for the study of human hepatocytes. The data showed MC-LR induced Fas and FasL expression, at both mRNA and protein levels. We also found MC-LR induced apoptosis at the same incubation condition at which it induced Fas and FasL expression. The data also revealed MC-LR promoted nuclear translocation and activation of p65 subunit of NF-κB. By applying siRNA to knock down p65 in HepG2 cells, we successfully impaired the activation of NF-κB by MC-LR. In these p65 knockdown cells, we also observed significant reduction of MC-LR-induced Fas expression, FasL expression, and apoptosis. These findings demonstrate that the NF-κB mediates the induction of Fas and FasL as well as cellular apoptosis by MC-LR in HepG2 cells. The results bring important information for understanding how MC-LR induces apoptosis in hepatocytes.     

Mericarp morphology and its systematic implications for the genus Salvia L. section Hymenosphace Benth. (Lamiaceae) in Turkey

Mericarp morphology of 15 taxa of Salvia L. section Hymenosphace Benth. in Turkey were investigated by light microscopy (LM) and scanning electron microscopy (SEM) to evaluate the utility of mericarp characters in systematic studies. Mericarps ranged from 2.50 to 5.38?mm in length and 2.04 to 4.70?mm in width. Mericarp shape was prolate-spheroid or near spherical with a length-to-width ratio of 1.02?C1.48. Transverse sections of the mericarps were rounded or rounded-trigonous. Mericarp surfaces presented colliculate, reticulate, verrucate or foveate sculpturing patterns, mostly as a result of the sculpturing of the exocarp cell walls with the pattern determined by whether the periclinal walls were concave or convex and whether the anticlinal walls were raised or sunken. Colliculate surface sculpturing (periclinal walls convex) was the most common among the taxa examined. The variation in the nature of surface sculpturing, mericarp shape and size, exocarp cell shape, nature of transverse sections and abscission scar diameter proved useful diagnostic characters. Variation was sufficient to distinguish taxa at species level, including morphologically similar species. Data provided here are also relevant to phylogenetic questions at higher levels within Salvia.