894 resultados para Transcutaneous immunization, Imiquimod, squalen, jojoba wax, freeze dried solid nanoemulsion, sucrose fatty acid esters, emulsion gel


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Despite decades of work, an effective HIV vaccine remains elusive. In an effort to elicit protective immunity, investigators have sought to define vaccines able to elicit durable HIV-specific B-cell and T-cell activities. Additionally, vaccines are sought which can induce antibodies of a variety of isotypes, as each isotype possesses unique attributes in terms of opsonization, Fc receptor binding capacity, complement fixation and location. One prominent new vaccine strategy, applied to numerous distinct antigenic systems is the prime boost-regimen, with DNA, vaccinia virus (VV), and/or purified recombinant protein. To examine the durability, location and isotype distribution of responses induced by prime-boost regimens, we tested successive immunizations with DNA, VV and protein (D-V-P), comparing three forms of protein inoculations: (i) purified protein administered intramuscularly with complete Freunds adjuvant, (ii) purified protein administered intranasally, and (iii) purified protein conjugated to oxidized mannan, administered intranasally. We found that all three protocols elicited serum antibodies of multiple isotypes, with serum IgA being most prominent among mice immunized with mannan-conjugated protein. All D-V-P protocols, regardless of protein form or route, also elicited antibody responses at mucosal surfaces. In bronchoalveolar lavage, a tendency toward IgA production was again most prominent in mice boosted with the protein–mannan conjugate. Both B-cell and T-cell responses were sustained for more than 1 year post-immunization following each form of vaccination. Contemporaneous with long-lasting serum and mucosal antibodies were antibody forming cells in the bone marrow of primed animals. Results highlight the D-V-P vaccination strategy as a promising approach for attaining durable, multi-isotype B-cell and T-cell activities toward HIV.

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Despite the removal of the mercury (Hg)-based preservative thimerosal from vaccines listed on the Australian Immunization Program Schedule for children, concerns remain among some researchers and parents for the safety of the present schedule, in part due to a fear of residual trace levels of Hg. The purpose of this study was to independently assess childhood vaccines for the presence of Hg. Eight vaccines administered to children under the age of 5 yr were assessed for Hg content via a DMA-80 direct mercury analyzer. Seven of the 8 vaccines contained no detectable levels of Hg (less than 1 ppb); however, 1 vaccine (Infanrix hexa) tested positive for Hg at 10 ppb. The result was confirmed and validated by retesting the original sample. Follow-up testing was conducted on three additional samples of Infanrix hexa (one from the same production lot and two from a different lot). All three tested positive for Hg (average of 9.7 ppb). Although the levels of Hg detected are substantially lower than any established exposure safety limits, the results of this study reveal that inaccuracies exist in public health messages, professional communications, and official documentation regarding Hg content in at least one childhood vaccine. In the interests of public health, it is incumbent on vaccine manufacturers and responsible agencies such as the Therapeutic Goods Administration and the Federal Department of Health and Ageing to address this issue as a matter of urgency.

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Build-up of earwax is a common reason for attendance in primary care. Current practice for earwax removal generally involves the use of a softening agent, followed by irrigation of the ear if required. However, the safety and benefits of the different methods of removal are not known for certain.

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Excessive ear wax can lead to symptoms such as hearing loss, tinnitus, itching, vertigo, and pain. Treatment to remove ear wax is generally carried out in primary care, and recent estimates suggest that up to 2 million ear irrigations are performed in England and Wales each year.1 This places a considerable demand on GP surgeries. A range of simple and often inexpensive remedies and proprietary drops can be used either to dissipate the wax orsoften it prior to removal. Although removal through irrigation usually occurs in primary care, some people may self-treat. Treatments offered often appear to be based on custom and local practice, rather than an awareness of the comparative effectiveness and costs of the different alternatives. Although evidence on the efficacy of different treatments has been published, no study has examined both clinical and cost-effectiveness. This report summarises a systematic review and economic evaluation of different approaches to ear wax removal taken from a UK perspective.

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The microencapsulation of tuna oil in gelatin-sodium hexametaphosphate (SHMP) using complex coacervation was optimised for the stabilisation of omega-3 oils, for use as a functional food ingredient. Firstly, oil stability was optimised by comparing the accelerated stability of tuna oil in the presence of various commercial antioxidants, using a Rancimat™. Then zeta-potential (mV), turbidity and coacervate yield (%) were measured and optimised for complex coacervation. The highest yield of complex coacervate was obtained at pH 4.7 and at a gelatin to SHMP ratio of 15:1. Multi-core microcapsules were formed when the mixed microencapsulation system was cooled to 5 °C at a rate of 12 °C/h. Crosslinking with transglutaminase followed by freeze drying resulted in a dried powder with an encapsulation efficiency of 99.82% and a payload of 52.56%. Some 98.56% of the oil was successfully microencapsulated and accelerated stability using a Rancimat™ showed stability more than double that of non-encapsulated oil.

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Identifying influential nodes is of theoretical significance in network immunization which is one of important methods to prevent virus propagation through protecting the influential nodes in a network. Lots of methods have been proposed to find these influential nodes based on the topological characteristics of a network (e.g., degree, betweenness or K-shell). Whereas due to the diversity of network topologies, these methods are not always effective in identifying influential nodes in any benchmark networks. We combine the advantages of existing methods based on attribute ranking and propose a universal ranking method, namely MAF (Multiple Attribute Fusion), to identify influential nodes from a complex network. We compare the efficiency of our proposed method with existing immunization strategies in different types of networks. Simulation results in the interactive email model show that the immunized nodes selected by MAF can restrain virus propagation effectively.

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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Cyclodextrins (CDs) are annular oligosaccharides containing 6-12 glucose unities joined together by alpha-1,4 bonds. They have a conical-truncated shape with a lipophilic cavity in which different molecules can be included resulting in a stable inclusion complex. The cyclodextrins have been widely applied in pharmaceutical technology with the objective of increasing the solubility, stability and bioavailability of drugs in different pharmaceutical dosage forms, such as tablets. In order to obtain beta-CD tablets, liquid dispersions of drug/beta-CD are usually submitted to different drying processes, like spray-drying, freeze-drying or slow evaporation, being this dry material added to a number of excipients. However, such drying processes can generate particulate materials showing problems of flow and compressibility, needing their conversion into granulates by means of wetting with granulation liquid followed by additional drying. In this work, the main objective was to evaluate the preparation of tablets without the need of this additional drying step. For this purpose an aqueous dispersion containing acetaminophen/beta-CD complex and cornstarch was dried using a spouted bed and the obtained granules were compressed in tablets. Acetaminophen was used as model drug due to its low water solubility and the inexpensive and widely available cornstarch was chosen as excipient. Acetaminophen powder was added into a beta-cyclodextrin solution prepared in distilled water at 70 degrees C. Stirring was kept until this dispersion cooled to room temperature. Then cornstarch was added and the resulting dispersion was dried in spouted bed equipment. This material was compressed into tablets using an Erweka Korsh EKO tablet machine. This innovative approach allowed the tablets preparation process to be carried out with fewer steps and represents a technological reliable strategy to produce beta-cyclodextrin inclusion complexes tablets. (C) 2010 Elsevier By. All rights reserved.

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The objectives of the present study were to optimize the protocol of mouse immunization with Paracoccidioides brasiliensis antigens (Rifkind's protocol) and to test the modulation effect of cyclophosphamide (Cy) on the delayed hypersensitivity response (DHR) of immunized animals. Experiments were carried out using one to four immunizing doses of either crude particulate P. brasiliensis antigen or yeast-cell antigen, followed by DHR test four or seven days after the last immunizing dose. The data demonstrated that an immunizing dose already elicited response; higher DHR indices were obtained with two or three immunizing doses; there were no differences between DHR indices of animals challenged four or seven days after the last dose. Overall the inoculation of two or three doses of the yeast-cell antigen, which is easier to prepare, and DHR test at day 4 simplify the original Rifkind's immunization protocol and shorten the duration of the experiments. The modulation effect of Cy on DHR was assayed with administration of 2.5, 20 and 100 mg/kg weight at seven day intervals starting from day 4 prior to the first immunizing dose. Only the treatment with 2.5 mg Cy increased the DHR indices. Treatment with 100 mg Cy inhibited the DHR, whereas 20 mg Cy did not affect the DHR indices. Results suggest an immunostimulating effect of low dose of Cy on the DHR of mice immunized with P. brasiliensis antigens.