Dengue virus (DENV) is an arbovirus that belongs to the Flaviviridae family. Studies reveal that peptides secreted by amphibians have many functions, such as antiviral and antimicrobial activities. ...As there is no antiviral drug effective against the DENV, the antiviral activity of a synthetic peptide called HS-1, derived from the secretion of the anuran Hypsiboas semilineatus, has been evaluated. The assays of neutralization in the Vero cells show a complete inhibition of infection of the serotypes 2 and 3. Furthermore, the direct action of peptides on the viral particle can be observed through atomic force microscopy. In vivo tests display 80% protection against the dengue-2 virus due to the presence of HS-1, which reveals its potential as an antiviral against the DENV.
•The use of antimicrobial peptides (AMPs) as antivirals has increased in recent times and has shown promise.•Many molecules have been described as being able to inhibit viral replication, such as, analogs of defensins, dermaseptins, and latarcins.•On account of the lack of a vaccine and treatment against the dengue virus, it has been considered necessary to test antivirals against the dengue virus.•The results are promising against dengue-2 and dengue-3 and the antivirals tested have shown efficiency in both in vitro and in vivo experiments, in which the antiviral appears to act directly on the viral particle, disrupting the lipoprotein envelope.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Rhodnius montenegrensis (Triatominae), a potential vector of Chagas disease, was described after R. robustus-like bugs from southwestern Amazonia. Mitochondrial cytb sequence near-identity with ...sympatric R. robustus (genotype II) raised doubts about the taxonomic status of R. montenegrensis, but comparative studies have reported fairly clear morphological and genetic differences between R. montenegrensis and laboratory stocks identified as R. robustus. Here, we use a transcriptome-based approach to investigate this apparent paradox.
We retrieved publicly-available transcriptome sequence-reads from R. montenegrensis and from the R. robustus stocks used as the taxonomic benchmark in comparative studies. We (i) aligned transcriptome sequence-reads to mitochondrial (cytb) and nuclear (ITS2, D2-28S and AmpG) query sequences (47 overall) from members of the R. prolixus-R. robustus cryptic-species complex and related taxa; (ii) computed breadth- and depth-coverage for the 259 consensus sequences generated by these alignments; and, for each locus, (iii) appraised query sequences and full-breadth-coverage consensus sequences in terms of nucleotide-sequence polymorphism and phylogenetic relations. We found evidence confirming that R. montenegrensis and R. robustus genotype II are genetically indistinguishable and, hence, implying that they are, in all likelihood, the same species. Furthermore, we found compelling genetic evidence that the benchmark 'R. robustus' stocks used in R. montenegrensis description and in later transcriptome-based comparisons are in fact R. prolixus, although likely mixed to some degree with R. robustus (probably genotype II, a.k.a. R. montenegrensis).
We illustrate how public-domain genetic/transcriptomic data can help address challenging issues in disease-vector systematics. In our case-study, taxonomic confusion apparently stemmed from the misinterpretation of sequence-data analyses and misidentification of taxonomic-benchmark stocks. More generally, and together with previous reports of mixed and/or misidentified Rhodnius spp. laboratory colonies, our results call into question the conclusions of many studies (on morphology, genetics, physiology, behavior, bionomics or interactions with microorganisms including trypanosomes) based on non-genotyped 'R. prolixus' or 'R. robustus' stocks. Correct species identification is a prerequisite for investigating the factors that underlie the physiological, behavioral or ecological differences between primary domestic vectors of Chagas disease, such as R. prolixus, and their sylvatic, medically less-relevant relatives such as R. robustus (s.l.) including R. montenegrensis.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
Newcastle disease virus (NDV) can infect over 250 bird species with variable pathogenicity; it can also infect humans in rare cases. The present study investigated an outbreak in feral pigeons in São ...Paulo city, Brazil, in 2019. Affected birds displayed neurological signs, and hemorrhages were observed in different tissues. Histopathology changes with infiltration of mononuclear inflammatory cells were also found in the brain, kidney, proventriculus, heart, and spleen. NDV staining was detected by immunohistochemistry. Twenty-seven out of thirty-four tested samples (swabs and tissues) were positive for Newcastle disease virus by RT-qPCR test, targeting the M gene. One isolate, obtained from a pool of positive swab samples, was characterized by the intracerebral pathogenicity index (ICPI) and the hemagglutination inhibition (HI) tests. This isolate had an ICPI of 0.99, confirming a virulent NDV strain. The monoclonal antibody 617/161, which recognizes a distinct epitope in pigeon NDV strains, inhibited the isolate with an HI titer of 512. A complete genome of NDV was obtained using next-generation sequencing. Phylogenetic analysis based on the complete CDS F gene grouped the detected isolate with other viruses from subgenotype VI.2.1.2, class II, including one previously reported in Southern Brazil in 2014. This study reports a comprehensive characterization of the subgenotype VI.2.1.2, which seems to have been circulating in Brazilian urban areas since 2014. Due to the zoonotic risk of NDV, virus surveillance in feral pigeons should also be systematically performed in urban areas.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
This work studies the kinetics of CO2 absorption into N,N-diethylethanolamine (DEEA) solutions. A comprehensive literature review is presented, in an attempt to understand the reasons behind the ...scatter observed in the literature data. Experiments were performed to measure the physical solubility of N2O in aqueous DEEA solutions in a concentration and temperature range that encloses the kinetics data range. Additionally, new data on mass transfer and kinetics of CO2 into aqueous DEEA solutions were produced in a stirred cell reactor. The data show an unexpected behaviour from 3M DEEA and up, which is not explained by taking the system non-idealities into consideration and revaluating the kinetics using activity basis. A DEEA clustering hypothesis is proposed to explain such behaviour. It is shown that the clustering hypothesis is compatible with the thermodynamic properties of aqueous DEEA solutions, and can be used to qualitatively explain the solubility and kinetics data presented in this work.
•There is a scatter in studies on the kinetics of CO2 absorption into DEEA solutions.•New kinetics data show an unexpected behaviour from 3M DEEA and up.•The DEEA clustering hypothesis is proposed to explain such behaviour.•The clustering hypothesis qualitatively explains the new solubility and kinetics data.•The clustering hypothesis matches the thermodynamic properties of DEEA solutions.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Whole mitogenome sequences (mtDNA) have been exploited for insect ecology studies, using them as molecular markers to reconstruct phylogenies, or to infer phylogeographic relationships and gene flow. ...Recent Anopheles phylogenomic studies have provided information regarding the time of deep lineage divergences within the genus. Here we report the complete 15,393 bp mtDNA sequences of Anopheles aquasalis, a Neotropical human malaria vector. When comparing its structure and base composition with other relevant and available anopheline mitogenomes, high similarity and conserved genomic features were observed. Furthermore, 22 mtDNA sequences comprising anopheline and Dipteran sibling species were analyzed to reconstruct phylogenies and estimate dates of divergence between taxa. Phylogenetic analysis using complete mtDNA sequences suggests that A. aquasalis diverged from the Anopheles albitarsis complex ~28 million years ago (MYA), and ~38 MYA from Anopheles darlingi. Bayesian analysis suggests that the most recent ancestor of Nyssorhynchus and Anopheles + Cellia was extant ~83 MYA, corroborating current estimates of ~79-100 MYA. Additional sampling and publication of African, Asian, and North American anopheline mitogenomes would improve the resolution of the Anopheles phylogeny and clarify early continental dispersal routes.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
This study aimed at investigating the effect of microencapsulated microwave-assisted extracts of pitaya peel on color, texture and oxidative stability of pork patties pressurized at 500 MPa for ...10 min and stored at 4 °C during 9 days. Different enhancement levels, namely 0 (NC and PNC), 100 (P1) and 1000 (P10) ppm were investigated. High pressure processing (HPP) accelerated (P ≤ 0.05) color (L* and a* values) and texture changes, as well as lipid and protein oxidation during refrigerated storage. Butyl hydroxytoluene (BHT), P1 and P10 demonstrated a protective effect (P ≤ 0.05) against the alterations promoted by HPP. Moreover, P1 and P10 demonstrated potential for inhibiting (P ≤ 0.05) protein oxidation induced by HPP and thus, minimized (P ≤ 0.05) hardness and chewiness changes in the pork matrix. Further studies should be conducted to investigate the scalability of the application at the industrial scale.
•Pitaya peel extract were obtained by microwave assisted extraction.•Pitaya peel extracts were microencapsulated and applied in pressurized pork.•HPP at 500 MPa for 10 min enhanced the oxidative process of ground pork.•Microencapsulated pitaya peel extract was effective against changes promoted by HPP.•Pitaya peel extract at 100 and 1000 ppm levels had potential as natural antioxidant.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
Dengue is a major arbovirus affecting humans today. With the growing number of cases, it is essential to have large-scale production of antigens for the development of diagnostic kits for the rapid ...detection of patients infected by the virus and consequent proper medical intervention for them. In this work, we express the prM/M and E proteins of dengue virus-3 in yeast Pichia pastoris KM71H. The proteins were produced in soluble form in the supernatant of the culture and were purified by precipitation with ammonium sulfate. The fraction of 80% of ammonium sulfate was used as an antigen in an indirect enzyme-linked immunosorbent assay (ELISA), providing a sensitivity of 82.61% and a specificity of 89.25%. Thus, the methodology proposed here showed promise for obtaining antigens of dengue viruses and creating quick and inexpensive diagnostic tests, which is of great value since large portions of the areas affected by this disease are economically neglected.
Dietary nitrate and nitrite have a notoriously bad reputation because of their proposed association with disease, in particular cancer. However, more recent lines of research have challenged this ...dogma suggesting that intake of these anions also possess beneficial effects after in vivo conversion to the vital signaling molecule nitric oxide. Such effects include improvement in cardiovascular, renal and metabolic function, which is partly mediated via reduction of oxidative stress. A recent study even indicates that low dose of dietary nitrite extends life span in fruit flies.
In this study, 200 middle-aged Wistar rats of both sexes were supplemented with nitrate or placebo in the drinking water throughout their remaining life and we studied longevity, biochemical markers of disease, vascular reactivity along with careful determination of the cause of death.
Dietary nitrate did not affect life span or the age-dependent changes in markers of oxidative stress, kidney and liver function, or lipid profile. Ex vivo examination of vascular function, however, showed improvements in endothelial function in rats treated with nitrate. Neoplasms were not more common in the nitrate group.
We conclude that chronic treatment with dietary nitrate does not affect life span in rats nor does it increase the incidence of cancer. In contrast, vascular function was improved by nitrate, possibly suggesting an increase in health span.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
This study contains a descriptive analysis of histoplasmosis in AIDS patients between 2006 and 2010 in the state of Ceará, Brazil. Additionally, the in vitro susceptibility of Histoplasma capsulatum ...isolates obtained during this period was assessed. We report 208 cases of patients with histoplasmosis and AIDS, describing the epidemiological, clinical, laboratory and therapeutic aspects. The in vitro antifungal susceptibility test was carried out by the microdilution method, according to Clinical and Laboratory Standards Institute, with H. capsulatum in the filamentous and yeast phases, against the antifungals amphotericin B, fluconazole, itraconazole, voriconazole and caspofungin. In 38.9% of the cases, histoplasmosis was the first indicator of AIDS and in 85.8% of the patients the CD4 cell count was lower than 100 cells/mm3. The lactate dehydrogenase levels were high in all the patients evaluated, with impairment of hepatic and renal function and evolution to death in 42.3% of the cases. The in vitro susceptibility profile demonstrated there was no antifungal resistance among the isolates evaluated. There was a significant increase in the number of histoplasmosis cases in HIV-positive patients during the period surveyed in the state of Ceará, northeastern Brazil, but no antifungal resistance among the recovered isolates of H. capsulatum.
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GEOZS, NUK, OILJ, SBJE, UL, UM, UPUK
Rheumatoid arthritis (RA) is a painful inflammatory disease of the joints which affects a considerable proportion of the world population, mostly women. If not adequately treated, RA patients can ...become permanently disabled. Importantly, not all the patients respond to the available anti-rheumatic therapies, which also present diverse side effects. In this context, monitoring of treatment response is pivotal to avoid unnecessary side effects and costs towards an ineffective therapy. Herein, we performed a pilot study to investigate the potential use of flow cytometry and attenuated total reflection-Fourier transform infrared (ATR-FTIR) spectroscopy as measures to identify responders and non-responders to leflunomide, a disease-modifying drug used in the treatment of RA patients. The evaluation of peripheral blood CD62L
polymorphonuclear cell numbers and ATR-FTIR vibrational modes in plasma were able to discriminate responders to leflunomide (LFN) three-months after therapy has started. Overall, the results indicate that both flow cytometry and ATR-FTIR can potentially be employed as additional measures to monitor early treatment response to LFN in RA patients.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
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