A nonhuman primate model for malaria vaccine development allowing reliable, stringent sporozoite challenge and evaluation of both cellular and antibody responses is needed. We therefore constructed a multicomponent, multistage DNA vaccine for the simian malaria species Plasmodium knowlesi including two preerythrocytic-stage antigens, the circumsporozoite protein (PkCSP) and sporozoite surface protein 2 (PkSSP2), and two blood stage antigens, apical merozoite antigen 1 (PkAMA1) and merozoite surface protein 1 (PkMSP1p42), as well as recombinant canarypox viruses encoding the four antigens (ALVAC-4). The DNA vaccine plasmids expressed the corresponding antigens in vitro and induced antiparasite antibodies in mice. Groups of four rhesus monkeys received three doses of a mixture of the four DNA vaccine plasmids and a plasmid encoding rhesus granulocyte-monocyte colony-stimulating factor, followed by boosting with a single dose of ALVAC-4. Three groups received the priming DNA doses by different routes, either by intramuscular needle injection, by intramuscular injection with a needleless injection device, the Biojector, or by a combination of intramuscular and intradermal routes by Biojector. Animals immunized by any route developed antibody responses against sporozoites and infected erythrocytes and against a recombinant PkCSP protein, as well as gamma interferon-secreting Tcell responses against peptides from PkCSP. Following challenge with 100 P. knowlesi sporozoites, 1 of 12 experimental monkeys was completely protected and the mean parasitemia in the remaining monkeys was significantly lower than that in 4 control monkeys. This model will be important in preclinical vaccine development.Malaria is a major cause of morbidity and mortality throughout tropical and subtropical regions of the world, accounting for an estimated 300 to 500 million infections and 1.5 to 3.0 million deaths annually (35). In the face of the spread of drugresistant malaria, efforts to develop an effective vaccine have become increasingly critical. Two observations suggest that a malaria vaccine may be achievable. First, immunization with radiation-attenuated sporozoites induces sterile protection in mice and humans (5, 17), mediated predominantly by CD8 ϩ T cells and gamma interferon (IFN-␥) and directed against the intrahepatocytic stage of the parasite. Second, adults in areas endemic for malaria develop partial clinical immunity, which is largely mediated by antibodies directed against blood stage antigens (23). A vaccine may need to induce both types of responses to provide optimal protection. DNA vaccines represent a flexible vaccine delivery system, capable of inducing both antibodies and cell-mediated immune responses to a wide variety of antigens. The flexibility of DNA vaccine technology permits the combination of multiple antigens from both the preerythrocytic and erythrocytic stages of the parasite. Previous studies from our laboratory have shown that DNA vaccines directed against either preerythrocytic-stage antigens (7, 26) or...
We tested a cytokine-enhanced, multiantigen, DNA priming and poxvirus boosting vaccine regimen for prevention of malaria in the Plasmodium knowlesi-rhesus macaque model system. Animals were primed with a mixture of DNA plasmids encoding two preerythrocytic-stage proteins and two erythrocytic-stage proteins from P. knowlesi and combinations of the cytokines granulocyte-macrophage colony-stimulating factor, interleukin-4, and tumor necrosis factor alpha and were boosted with a mixture of four recombinant, attenuated vaccinia virus strains encoding the four P. knowlesi antigens. Two weeks after boosting, the geometric mean immunofluorescence titers in the immunized groups against sporozoites and infected erythrocytes ranged from 160 to 8,096 and from 1,810 to 5,120, respectively. The geometric mean anti-P. knowlesi circumsporozoite protein (PkCSP) titers ranged from 1,761 to 24,242. Peripheral blood mononuclear cells (PBMC) from the immunized monkeys produced gamma interferon (IFN-␥) in response to incubation with pooled peptides from the PkCSP at frequencies of 10 to 571 spot-forming cells/10 6 PBMC. Following challenge with 100 infectious P. knowlesi sporozoites, 2 of 11 immunized monkeys were sterilely protected, and 7 of the 9 infected monkeys resolved their parasitemias spontaneously. In contrast, all four controls became infected and required treatment for overwhelming parasitemia. Early protection was strongly associated with IFN-␥ responses against a pool of peptides from the preerythrocytic-stage antigen, PkCSP. These findings demonstrate that a multistage, multiantigen, DNA priming and poxvirus boosting vaccine regimen can protect nonhuman primates from an otherwise lethal malaria sporozoite challenge.Each year, malaria parasites infect 270 to 350 million people and kill 1.5 to 2.7 million people, mostly children in subSaharan Africa (29); drug resistance is spreading rapidly, and there is currently no licensed vaccine. In a mammalian host Plasmodium sporozoites injected by a mosquito move within minutes to hepatocytes, in which they develop during several days before emerging to infect circulating erythrocytes. Two models suggest that immune control of malaria is possible. First, in mice (15), monkeys (10), and humans (3), immunization with radiation-attenuated sporozoites can provide sterile protection against sporozoite challenge, mediated by CD8 ϩ T cells and gamma interferon (IFN-␥) directed at the intrahepatocytic stage of the parasite (6). Adults in areas where malaria is endemic develop partial clinical immunity, which is largely mediated by antibodies directed against blood-stage antigens (19,21). An effective malaria vaccine will likely need to induce both T-cell responses against infected hepatocytes and antibodies against blood-stage parasites. While DNA vaccines represent a flexible vaccine technology, well adapted to simultaneous delivery of multiple antigens, they have been less than optimally immunogenic in human trials, inducing modest Tcell responses and small amounts of antibodies or no...
Large-scale functional genomics studies for malaria vaccine and drug development will depend on the generation of molecular tools to study protein expression. We examined the feasibility of a high-throughput cloning approach using the Gateway system to create a large set of expression clones encoding Plasmodium falciparum single-exon genes. Master clones and their ORFs were transferred en masse to multiple expression vectors. Target genes (n = 303) were selected using specific sets of criteria, including stage expression and secondary structure. Upon screening four colonies per capture reaction, we achieved 84% cloning efficiency. The genes were subcloned in parallel into three expression vectors: a DNA vaccine vector and two protein expression vectors. These transfers yielded a 100% success rate without any observed recombination based on single colony screening. The functional expression of 95 genes was evaluated in mice with DNA vaccine constructs to generate antibody against various stages of the parasite. From these, 19 induced antibody titers against the erythrocytic stages and three against sporozoite stages. We have overcome the potential limitation of producing large P. falciparum clone sets in multiple expression vectors. This approach represents a powerful technique for the production of molecular reagents for genome-wide functional analysis of the P. falciparum genome and will provide for a resource for the malaria resource community distributed through public repositories.
BackgroundThe association between depression, anxiety, and polycystic ovary syndrome (PCOS) is still unclear. Therefore, a systematic review and meta-analysis was conducted to assess the rates of comorbid psychiatric disorders among women with PCOS compared to women without it.MethodsPubMed/MEDLINE, Embase, PsycINFO, and Web of Science databases were searched from inception to November 27, 2015. Studies were eligible for inclusion if they were original reports in which the rates of mood (bipolar disorder, dysthymia, or major depressive disorder), obsessive–compulsive spectrum disorders, trauma- and stressor-related disorders, anxiety disorders or psychotic disorders, somatic symptom and related disorders, or eating disorders had been investigated among women with an established diagnosis of PCOS and compared with women without PCOS. Psychiatric diagnosis should have been established by means of a structured diagnostic interview or through a validated screening tool. Data were extracted and pooled using random effects models.ResultsSix studies were included in the meta-analysis; of these, five reported the rates of anxiety and six provided data on the rates of depression. The rate of subjects with anxiety symptoms was higher in patients with PCOS compared to women without PCOS (odds ratio (OR) =2.76; 95% confidence interval (CI) 1.26 to 6.02; Log OR =1.013; P=0.011). The rate of subjects with depressive symptoms was higher in patients with PCOS compared to women without PCOS (OR =3.51; 95% CI 1.97 to 6.24; Log OR =1.255; P<0.001).ConclusionAnxiety and depression symptoms are more prevalent in patients with PCOS.
Geographical variation in the reproductive biology of widespread species often occurs at their distributional boundaries. We sought to determine whether such variation has occurred in an invasive orchid, Oeceoclades maculata, across its naturalized range. We compared its reproductive biology in a Brazilian population with that published for a population on the Caribbean island of Puerto Rico. In the state of São Paulo, O. maculata flowers between December and February, at the height of the rainy season. Similar fruit sets were observed in manual self (76%) and cross (70.4%) pollination treatments. The fruit set of plants protected from both pollinators and rainfall was 6.1%, whereas plants exposed only to rainfall had a fruit set of 41.4%, slightly less than the controls (48.3%). Like the Puerto Rico population, reproduction is primarily through rain-assisted autogamy, but unlike observations made on the island, outcrossing can eventually occur. We observed two butterfly species (Heliconius ethilla narcaea and Heliconius erato phyllis) pollinating O. maculata. Secretory epidermal cells and trichomes of the spur lumen produced 0.7 mL of 25% (sucrose equivalents) nectar per flower each morning, which was stored in a dilated basal portion of the spur and reabsorbed by the afternoon. Thus, geographical variation in reproductive biology exists across the broad invasive range of O. maculata.
Aim/Purpose: This research aims to develop an information technology (IT) maturity model for incident management (IM) process that merges the most known IT frameworks’ practices. Our proposal intends to help organizations overcome the current limitations of multiframework implementation by informing organizations about frameworks’ overlap before their implementation. Background: By previously identifying frameworks’ overlaps it will assist organizations during the multi-framework implementation in order to save resources (human and/or financial). Methodology: The research methodology used is design science research (DSR). Plus, the authors applied semi-structured interviews in seven different organizations to demonstrate and evaluate the proposal. Contribution: This research adds a new and innovative artefact to the body of knowledge. Findings: The proposed maturity model is seen by the practitioners as complete and useful. Plus, this research also reinforces the frameworks’ overlap issue and concludes that some organizations are unaware of their actual IM maturity level; some organizations are unaware that they have implemented practices of other frameworks besides the one that was officially adopted. Recommendations for Practitioners: Practitioners may use this maturity model to assess their IM maturity level before multi-framework implementation. Moreover, practitioners are also incentivized to communicate further requirements to academics regarding multi-framework assessment maturity models. Recommendation for Researchers: Researchers may explore and develop multi-frameworks maturity models for the remaining processes of the main IT frameworks. Impact on Society: This research findings and outcomes are a step forward in the development of a unique overlapless maturity model covering the most known IT frameworks in the market thus helping organizations dealing with the increasing frameworks’ complexity and overlap. Future Research: Overlapless maturity models for the remaining IT framework processes should be explored.
The genus Vanilla is the most diverse in Vanilloideae, with ca 90 species distributed among tropical regions. Despite their economic importance, studies on pollination of Vanilla are very scarce and data on pollinators of species endemic to Brazil are lacking. Based on fieldwork and laboratory investigations, the floral biology of V. edwallii was studied. The pollinators and pollination process were recorded at the Serra do Japi reserve, state of São Paulo, southeastern Brazil, and the presence of floral reward was also investigated. Vanilla edwallii blooms in summer. The lateral inflorescences produce up to four pale green flowers. The white labellum is united to the base of the column forming a mentum. In the studied population V. edwallii is pollinated by Epicharis (Hoplepicharis) affinis, where the males exhibit a territorial behavior, defending flowers from other possible flower visitors. The pollen is deposited on the scutellum of bees when they abandon the flower. The mentum region is dry, suggesting no nectar production. The only secretory structures are osmophores dispersed on the inner surface of the lip responsible for production of a sweet fragrance, which together with color and morphology of flowers is related to bee attraction. The labellum is rich in mucilaginous cells, while the mucilaginous substance is retained inside the cells. The histochemical analysis also detected the presence of phenolic compounds and starch concentrated mainly at the adaxial surface of the lip and around the vascular bundles.
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