A deep insight into the sialome of male and female aedes aegypti mosquitoes

Only adult female mosquitoes feed on blood, while both genders take sugar meals. Accordingly, several compounds associated with blood feeding (i.e. vasodilators, anti-clotting, anti-platelets) are found only in female glands, while enzymes associated with sugar feeding or antimicrobials (such as lysozyme) are found in the glands of both sexes. We performed de novo assembly of reads from adult Aedes aegypti female and male salivary gland libraries (285 and 90 million reads, respectively). By mapping back the reads to the assembled contigs, plus mapping the reads from a publicly available Ae. aegypti library from adult whole bodies, we identified 360 transcripts (including splice variants and alleles) overexpressed tenfold or more in the glands when compared to whole bodies. Moreover, among these, 207 were overexpressed fivefold or more in female vs. male salivary glands, 85 were near equally expressed and 68 were overexpressed in male glands. We call in particular the attention to C-type lectins, angiopoietins, female-specific Antigen 5, the 9.7 kDa, 12–14 kDa, 23.5 kDa, 62/34 kDa, 4.2 kDa, proline-rich peptide, SG8, 8.7 kDa family and SGS fragments: these polypeptides are all of unknown function, but due to their overexpression in female salivary glands and putative secretory nature they are expected to affect host physiology. We have also found many transposons (some of which novel) and several endogenous viral transcripts (probably acquired by horizontal transfer) which are overexpressed in the salivary glands and may play some role in tissue-specific gene regulation or represent a mechanism of virus interference. This work contributes to a near definitive catalog of male and female salivary gland transcripts from Ae. aegypti, which will help to direct further studies aiming at the functional characterization of the many transcripts with unknown function and the understanding of their role in vector-host interaction and pathogen transmission

A deeper insight into the sialome of male and female Culex quinquefasciatus mosquitoes

Introduction: During evolution, blood-feeding arthropods developed a complex salivary mixture that can interfere with host haemostatic and immune response, favoring blood acquisition and pathogen transmission. Therefore, a survey of the salivary gland contents can lead to the identification of molecules with potent pharmacological activity in addition to increase our understanding of the molecular mechanisms underlying the hematophagic behaviour of arthropods. The southern house mosquito, Culex quinquefasciatus, is a vector of several pathogenic agents, including viruses and filarial parasites that can affect humans and wild animals. Results: Previously, a Sanger-based transcriptome of the salivary glands (sialome) of adult C. quinquefasciatus females was published based on the sequencing of 503 clones organized into 281 clusters. Here, we revisited the southern mosquito sialome using an Illumina-based RNA-sequencing approach of both male and female salivary glands. Our analysis resulted in the identification of 7,539 coding DNA sequences (CDS) that were functionally annotated into 25 classes, in addition to 159 long non-coding RNA (LncRNA). Additionally, comparison of male and female libraries allowed the identification of female-enriched transcripts that are potentially related to blood acquisition and/or pathogen transmission. Conclusion: Together, these findings represent an extended reference for the identification and characterization of the proteins containing relevant pharmacological activity in the salivary glands of C. quinquefasciatus mosquitoes.This work was supported by the Intramural Research Program of the Division of Intramural Research (AI001246 and AI000810), National Institute of Allergy and Infectious Diseases (NIAID), National Institutes of Health (NIH). This work utilized the computational resources of the NIH HPC Biowulf cluster (http://hpc.nih.gov). Open Access funding provided by the National Institutes of Health (NIH).S

Climate versus carbon dioxide controls on biomass burning: a model analysis of the glacial–interglacial contrast

Climate controls fire regimes through its influence on the amount and types of fuel present and their dryness. CO2 concentration constrains primary production by limiting photosynthetic activity in plants. However, although fuel accumulation depends on biomass production, and hence on CO2 concentration, the quantitative relationship between atmospheric CO2 concentration and biomass burning is not well understood. Here a fire-enabled dynamic global vegetation model (the Land surface Processes and eXchanges model, LPX) is used to attribute glacial–interglacial changes in biomass burning to an increase in CO2, which would be expected to increase primary production and therefore fuel loads even in the absence of climate change, vs. climate change effects. Four general circulation models provided last glacial maximum (LGM) climate anomalies – that is, differences from the pre-industrial (PI) control climate – from the Palaeoclimate Modelling Intercomparison Project Phase~2, allowing the construction of four scenarios for LGM climate. Modelled carbon fluxes from biomass burning were corrected for the model's observed prediction biases in contemporary regional average values for biomes. With LGM climate and low CO2 (185 ppm) effects included, the modelled global flux at the LGM was in the range of 1.0–1.4 Pg C year-1, about a third less than that modelled for PI time. LGM climate with pre-industrial CO2 (280 ppm) yielded unrealistic results, with global biomass burning fluxes similar to or even greater than in the pre-industrial climate. It is inferred that a substantial part of the increase in biomass burning after the LGM must be attributed to the effect of increasing CO2 concentration on primary production and fuel load. Today, by analogy, both rising CO2 and global warming must be considered as risk factors for increasing biomass burning. Both effects need to be included in models to project future fire risks

Gene expression and fatty acid profiling in longissimus thoracis muscle, subcutaneous fat, and liver of light lambs in response to concentrate or alfalfa grazing

A better understanding of gene expression and metabolic pathways in response to a feeding system is critical for identifying key physiological processes and genes associated with polyunsaturated fatty acid (PUFA) content in lamb meat. The main objective of this study was to investigate transcriptional changes in L. thoracis (LT) muscle, liver, and subcutaneous fat (SF) of lambs that grazed alfalfa (ALF) and concentrate-fed (CON) slaughtered at 23 kg and using the Affymetrix Ovine Gene 1.1 ST whole-genome array. The study also evaluated the relationship between meat traits in LT muscle, including color, pigments and lipid oxidation during 7 days of display, a-tocopherol content, intramuscular fat (IMF) content and the fatty acid (FA) profile. Lambs that grazed on alfalfa had a greater a-tocopherol concentration in plasma than CON lambs (P 0.05). Grazing increased the a-tocopherol content (P < 0.001) and decreased lipid oxidation on day 7 of display (P < 0.05) in LT muscle. The ALF group contained a greater amount of conjugated linoleic acid (CLA), C18:3 n-3, C20:5 n-3, C22:5 n-3, and C22:6 n-3 than did the CON group (P < 0.05). We identified 41, 96 and four genes differentially expressed in LT muscle, liver, and subcutaneous fat, respectively. The most enriched biological processes in LT muscle were skeletal muscle tissue development, being the genes related to catabolic and lipid processes downregulated, except for CPT1B, which was upregulated in the ALF lambs. Animals grazing alfalfa had lower expression of desaturase enzymes in the liver (FADS1 and FADS2), which regulate unsaturation of fatty acids and are directly involved in the metabolism of n-3 PUFA series. The results found in the current study showed that ingesting diets richer in n-3 PUFA might have negative effects on the de novo synthesis of n-3 PUFA by downregulating the FADS1 and FADS2 expression. However, feeding diets poorer in n-3 PUFA can promote fatty acid desaturation, which makes these two genes attractive candidates for altering the content of PUFAs in meat

Poly[(R)-3-hydroxybutyrate] production under different salinity conditions by a novel Bacillus megaterium strain

Bacillus megaterium uyuni S29, isolated from the Bolivian salt lake Uyuni, displays a high capability to produce poly[(R)-hydroxybutyrate] (PHB) in industrial culture media. In order to analyze the influence of salt on biomass formation and PHB production, cultivations at different NaCl concentrations were carried out according to the salinity conditions of the habitats of the strain’s original isolation. In this preliminary report, the strain showed considerable adaptability to media of different salinity, obtaining the best results for both cellular growth and PHB production in media containing 45 g/L NaCl. The strain grew at 100 g/L NaCl and PHB production was observed even at high salt levels of 250 g/L without unwanted concurrent spore formation. Its tolerance to high salt concentrations together with auspicious PHB productivity makes this strain appealing not only for PHB production, but also for other biotechnological applications such as the treatment of salty wastewater; additional studies will be needed to further increase PHB productivity.Postprint (published version

Nucleation and growth of precipitates in a V-microalloyed steel according to physical theory and experimental results

Using a theoretical model, the nucleus number and nucleation time were determined for a V-microalloyed steel. The calculated data has made it possible to plot the nucleus number vs. temperature, nucleation critical time vs. temperature, and precipitate critical radius vs. temperature. The nucleus number was calculated by integration of the nucleation rate expression. On the other hand, an experimental study was performed and the nucleation time vs. temperature was plotted (PTT diagram), thus allowing a comparison between the theoretical values and experimental results. It has been found that the growth of precipitates during precipitation obeys a quadratic growth equation and not a cubic coalescence equation. The experimentally determined growth rate coincides with the theoretically predicted growth rate. The experimental nucleation time is longer than the calculated time due to conceptual differences.Peer ReviewedPostprint (author's final draft

Preparation and optimization of a titanium-based feedstock for Fused Deposition Modeling

In this work the preparation and optimization of a titanium-based metal injection moulding (MIM) feedstock for Fused Deposition Modeling (FDM) is presented. The composition of the plastic binder system, consisting of a backbone polymer, a water-soluble polymer and a lubricant was optimized and MIM feedstocks with titanium contents ranging from 50 to 68 vol.% were prepared in a laboratory-scale internal mixer. During the feedstock preparation the torque of the mixing screws of the internal mixer was recorded, which allowed to determine an optimum Ti content of 59–61 vol.%. The morphology, thermal and rheological properties of the prepared MIM feedstocks were characterized using various techniques such as optical microscopy, SEM, FTIR, DSC, TGA, MFI and oscillatory rheometry. This study contributes to the emerging research on additive manufacturing of MIM feedstocks with the aim of producing pure titanium components with complicated shapes and high density from novel MIM feedstock as the starting material

Metastasis of spindle cell malignant melanoma in gallbladder

Malignant melanoma is an aggressive neoplasm with a high tendency to metastasize. Gastrointestinal metastases, although described in the literature, are infrequent. We present the case of a 51-year-old male patient with a surfcial spreading melanoma stage IIIc with BRAF mutation who presented a gallbladder outgrowth lesion, compatible with a polyp. A signifcant growth of the lesion was observed in subsequent TC studies and a laparoscopic cholecystectomy was performed. The anatomopathological study of the specimen confrmed the diagnosis of gallbladder metastasis due to epithelioid and spindle cell malignant melanoma. The presence of a gallbladder lesion in the context of a patient diagnosed with melanoma should establish the diagnostic suspicion of metastasis, and an early extension study and laparoscopic cholecystectomy should be considered. The palliative surgical approach to avoid hepatobiliary symptomatology can be considered