Glycogen synthase kinase-3 (GSK-3) is classically described as a key enzyme involved in glycogen metabolism in mammals. It has been shown to be highly conserved among several organisms, mainly in the ...catalytic domain region. This enzyme has already been described in Rhipicephalus (Boophilus) microplus and the ovaries of females appeared to be the major site of GSK-3 transcription. The treatment with GSK-3 specific inhibitor (alsterpaullone, bromo-indirubin-oxime 6 and indirubin-3-oxime) caused a reduction in oviposition and egg hatching in completely engorged female ticks. The effect was more pronounced in partially engorged females when alsterpaullone was administrated by artificial capillary feeding. Moreover, GSK-3 gene silencing by RNAi in partially engorged females reduced significantly both oviposition and hatching. The study of tick embryogenesis and proteins that participate in this process has been suggested as an important means for the development of novel strategies for parasite control. GSK-3 is an essential protein involved in embryonic processes and for this reason it has already been suggested as a possible antigen candidate for tick control.
An aspartic endopeptidase was purified in our laboratory from Rhipicephalus (Boophilus) microplus eggs Logullo, C., Vaz, I.S., Sorgine, M.H., Paiva-Silva, G.O., Faria, F.S., Zingali, R.B., De Lima, ...M.F., Abreu, L., Oliveira, E.F., Alves, E.W., Masuda, H., Gonzales, J.C., Masuda, A., and Oliveira, P.L., 1998. Isolation of an aspartic proteinase precursor from the egg of a hard tick, Rhipicephalus (Boophilus) microplus. Parasitology 116, 525–532. Boophilus yolk cathepsin (BYC) was tested as component of a protective vaccine against the tick, inducing a significant immune response in cattle da Silva, V.I., Jr., Logullo, C., Sorgine, M., Velloso, F.F., Rosa de Lima, M.F., Gonzales, J.C., Masuda, H., Oliveira, P.L., and Masuda, A., 1998. Immunization of bovines with an aspartic proteinase precursor isolated from Rhipicephalus (Boophilus) microplus eggs. Vet. Immunol. Immunopathol. 66, 331–341. In this work, BYC was cloned and its primary sequence showed high similarity with other aspartic endopeptidases. In spite of this similarity, BYC sequence shows many important differences in relation to other aspartic peptidases, the most important being the lack of the second catalytic Asp residue, considered to be essential for the catalysis of this class of endopeptidases. When we determined BYC cleavage specificity by LC-MS, we found out that it presents a preference for hydrophobic residues in P1 and P1' in accordance to most aspartic endopeptidases. Also, when analyzed by circular dicroism, BYC presented high β sheet content, also a characteristic of aspartic endopeptidases. On the other hand, although both native and recombinant BYC are catalytically active, they present a very low specific activity, what seems to indicate that this peptidase will digest its natural substrate, vitellin, very slowly. We speculate that such a slow Vn degradative process might constitute an important strategy to preserve egg protein content to the hatching larvae.
Yolk biogenesis and consumption have been well conserved in oviparous animals throughout evolution. Most egg-laying animals store yolk proteins within the oocytes' yolk granules (Ygs). Following ...fertilization, the Ygs participate in controlled pathways of yolk breakdown to support the developing embryo's anabolic metabolism. While the unfolding of the yolk degradation program is a crucial process for successful development in many species, the molecular mechanisms responsible for yolk mobilization are still mysterious and have mostly not been explored. Here, we investigate the functional role of the oocyte maternally accumulated mRNAs of a protein phosphatase (PP501) and two aspartic proteases (cathepsin-D 405, CD405 and cathepsin-D 352, CD352) in the yolk degradation and reproduction of the insect vector of Chagas disease
. We found that PP501 and CD352 are highly expressed in the vitellogenic ovary when compared to the other organs of the adult insect. Parental RNAi silencing of PP501 resulted in a drastic reduction in oviposition and increased embryo lethality whereas the silencing of CD352 resulted only in a slight decrease in oviposition and embryo viability. To further investigate the PP501-caused high reproduction impairment, we investigated the Ygs biogenesis during oocyte maturation and the activation of the yolk degradation program at early development. We found that the Ygs biogenesis was deficient during oogenesis, as seen by flow cytometry, and that, although the PP501-silenced unviable eggs were fertilized, the Ygs acidification and acid phosphatase activity were affected, culminating in a full impairment of the yolk proteins degradation at early embryogenesis. Altogether we found that PP501 is required for the oocyte maturation and the activation of the yolk degradation, being, therefore, essential for this vector reproduction.
Use and knowledge of Cactaceae in Northeastern Brazil Lucena, Camilla Marques de; Lucena, Reinaldo Farias Paiva de; Costa, Gabriela Maciel ...
Journal of ethnobiology and ethnomedicine,
2013-Aug-28, 2013-08-28, 20130828, Letnik:
9, Številka:
1
Journal Article
Recenzirano
Odprti dostop
This study aimed to record the use, and knowledge that residents from São Francisco community (Paraiba, Brazil) have regarding the Cactaceae.
Semi-structured interviews were carried out with 118 ...informants; 50 men and 68 women. The cacti cited in this study were organised into use categories and use values were calculated. Differences in the values applied to species and use categories by men and women were compared via a G test (Williams).
The nine species identified were: Cereus jamacaru DC., Melocactus bahiensis (Brtitton & Rose) Luetzelb., Nopalea cochenillifera (L.) Salm-Dyck., Opuntia ficus indica (L.) Mill, Opuntia stricta (Haw.) Haw., Pilosocereus gounellei (F.A.C. Weber) Byles & Rowley, Pilosocereus pachycladus F. Ritter, Tacinga inamoena (K. Schum) N.P. Taylor & Stuppy, Tacinga palmadora (Britton & Rose) N.P. Taylor & Stuppy. In total, 1,129 use citations were recorded, divided into 11 categories. The use value categories with the highest scores were forage (0.42), food (0.30) and construction (building) (0.25). P. pachycladus showed the greatest use value, versatility and number of plant parts used.
The survey showed that the Cactaceae is extremely important for several uses and categories attributed to different species. Apart from contributing to the ethnobotanical knowledge of the Cactaceae, another important focus of this study was to reinforce the necessity for further studies that record the traditional knowledge about this plant family, which has been lost in younger generations.
Two proteins from the eggshell of
Rhodnius prolixus were isolated, characterized and named Rp30 and Rp45 according to their molecular masses. Purified proteins were used to obtain specific antiserum ...which was later used for immunolocalization. The antiserum against Rp30 and Rp45 detected their presence inside the follicle cells, their secretion and their association with oocyte microvilli. Both proteins are expressed during the final stage of vitellogenesis, preserved during embryogenesis and discarded together with the eggshell. The amino terminals were sequenced and both proteins were further cloned using degenerated primers. The amino acid sequences appear to have a tripartite arrangement with a highly conserved central domain which presents a repetitive motif of valine–proline–valine (VPV) at intervals of 15 amino acid residues. Their amino acid sequence showed no similarity to any known eggshell protein. The expression of these proteins was also investigated; the results demonstrated that this occurred strictly in choriogenic follicles. Antifungal activity against
Aspergillus niger was found to be associated with Rp45 but not with Rp30.
A. niger exposed to Rp45 protein induced growth inhibition and several morphological changes such as large vacuoles, swollen mitochondria, multi-lamellar structures and a disorganized cell wall as demonstrated by electron microscopy analysis.
Youths living in crowded impoverished urban areas face higher risk of infection by SARS-CoV-2. This article presents lessons learned from a preventive intervention project intersected by the COVID-19 ...crisis that moved from a mix-methods study design to online ethnography. The 'home-officed' research team e-witnessed high-school students' daily lives and collaborated in youths' and community-based organisations' responses in the territories where they study and live. Psychosocial distress increased, also driven by the disastrous governmental response to the health and economic crises. There was growing anxiety about meeting friends and dating, with structural limits for sustaining the recommended social distancing, which added to gender/sexuality-based violence. Simultaneously, we observed students becoming relevant actors through co-producing preventive practices, surpassing risk-group notions and combining SARS-CoV-2 prevention with sexuality, gender, racism and mental-health issues. They managed internet-mediated applications to promote critical thinking and collective actions aimed at health promotion among their peers, from their homes. Freire's concept of 'untested-feasibility' fostered researchers', students' and community leaders' imaginations in the face of this unprecedented crisis, thereby enhancing social responses to the epidemic to become rights-based comprehensive dialogical preventive activities. This ongoing intervention-research stresses how prevention sciences can go beyond reduction of this pandemic to a viral event.
Abstract The Santos Basin (SB) is the main petroliferous basin in the Brazilian continental margin and one of the most studied marine areas in Brazil. However, historical data suggest that new ...efforts should be carried out to acquire quantitative biological data, especially in the deep sea, to establish the baseline of essential ocean variables in different ecosystems for future monitoring programs. The Brazilian energy company Petrobras planned and executed 24 oceanographic cruises over a period of 2 years to assess the benthic (SANSED cruise) and pelagic (SANAGU cruise) systems of the SB (356 days at sea in 2019 and 2021/2022). These efforts were part of the Santos Project, which comprised a comprehensive environmental study aimed at investigating benthic and pelagic variables to characterize ecology, biogeochemistry, thermohaline properties of water masses, and ocean circulation patterns, geomorphology, and sedimentology, as well as organic and inorganic chemistry. Here we present the detailed sampling designs and the field methods employed on board, during the SB scientific cruises. All sampling protocols were based on standardized approaches. For the benthos analyses, triplicate sediment samples were performed using a GOMEX-type box corer (0.25 m²) or a large modified Van Veen grab (0.75 m²) at 100 stations ranging from 25 to 2400 m depth. At each station, 25 geochemical and physico-chemical parameters were analyzed in addition to micro-, meio-, and macrofauna and living foraminifera samples. For the pelagic system, 60 stations were selected to investigate the plankton community, ranging in size from pico- to macroplankton, through vertical, horizontal, and oblique net hauls (20, 200, and 500 μm mesh size), as well as 25 biogeochemical parameters collected with an aid of a CTD-rosette sampler. Part of this scientific information also serves the Regional Environmental Characterization Project (PCR-BS) in support of Petrobras’ Santos Basin drilling licensing process led by the Brazilian Environmental Agency – IBAMA. This project contributes to the sustainable development of the SB, in line with the guidelines of the United Nations Decade of Ocean Science for Sustainable Development.
HIV-related non-Hodgkin lymphomas of the oral cavity are rare lesions with aggressive clinical behaviour. The aim of this study is to describe the clinicopathological features of a series of ...HIV-related oral non-Hodgkin lymphomas.
Eleven cases of oral lymphomas affecting HIV-positive patients were retrieved from 2012 to 2019. Clinicopathological features regarding age, sex, tumour location, clinical presentation, laboratory findings, disease stage and follow-up were obtained. Histologic, immunohistochemical and in situ hybridization for EBV detection were done for diagnosis confirmation. Overall survival was estimated by Kaplan-Meier curve.
Males predominated, with a mean age of 40.3 years-old. Maxilla and mandible were the mostly affected. Plasmablastic lymphoma and diffuse large B-cell lymphoma not otherwise specified (NOS) were the main histological types. Lesions presented as reddish ulcerated swellings, representing the first sign of AIDS in six cases. Stage IV were common (7 cases) and the mean HIV viral load was 10,557 copies/mL, with a mean of 266 CD4+ cells/mm3, 1,278 CD8+ cells/mm3 and a CD4+/CD8+ ratio of 0.26. Eight patients died of the disease (72.7%). Overall survival revealed that 78.2% of the patients died after 21 months of follow-up.
HIV-related oral lymphomas present a poor prognosis usually diagnosed in advanced stages and in our series plasmablastic lymphoma was the most common subtype.
Hemoglobin digestion in the midgut of hematophagous animals results in the release of its prosthetic group, heme, which is a pro-oxidant molecule. Heme enzymatic degradation is a protective mechanism ...that has been described in several organisms, including plants, bacteria, and mammals. This reaction is catalyzed by heme oxygenase and results in formation of carbon monoxide, ferrous ion, and biliverdin IXα. During digestion, a large amount of a green pigment is produced and secreted into the intestinal lumen of Aedes aegypti adult females. In the case of another blood-sucking insect, the kissing-bug Rhodnius prolixus, we have recently shown that heme degradation involves a complex pathway that generates dicysteinyl-biliverdin IX gamma. The light absorption spectrum of the Aedes purified pigment was similar to that of biliverdin, but its mobility on a reverse-phase chromatography column suggested a compound less hydrophobic than biliverdin IXα. Structural characterization by ESI-MS revealed that the mosquito pigment is the α isomer of biliverdin bound to two glutamine residues by an amide bond. This biglutaminyl-biliverdin is formed by oxidative cleavage of the heme porphyrin ring followed by two subsequent additions of glutamine residues to the biliverdin IXα. The role of this pathway in the adaptation of this insect vector to a blood-feeding habit is discussed.
The synthesis and secretion of vitellogenin by the ovary of
Rhodnius prolixus was investigated. Using whole ovary or epithelial cells isolated from follicles of different sizes, it is shown that the ...follicle cells are a site of synthesis for this protein in the ovary. The ovaries or follicle cells were incubated in vitro with
35S-methionine or
32Pi and the secretion of newly synthesized ovarian vitellogenin (O-Vg) was estimated by the radioactivity associated with the immunoprecipitate or acid-precipitate proteins in the culture medium. The radioactive O-Vg was analyzed by SDS-PAGE followed by autoradiography or after elution from a DEAE-Toyopearl column. The presence of O-Vg inside the follicle cells was detected by immunofluorescence and immunogold labels. Both methods revealed strong labeling inside the follicle cells. While the capacity for total protein synthesis by the follicle cells was maximal during the early phase of vitellogenesis (in small follicles), the synthesis of O-Vg reached its peak during the late phase of oocyte growth, just before formation of the chorion. A possible role for ovarian vitellogenin in
Rhodnius and its relationship with Vg synthesis by the fat body is discussed.
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