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1.
Molecules ; 29(11)2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38893508

RESUMO

In recent years, the utilization of natural components has become crucial across various industries, including medicine. Particularly in biomedical contexts, hydrogel materials are of significant importance. Therefore, the objective of this research was to develop and analyze hydrogel materials infused with vitamin C. A key focus of this study was to conduct multiple syntheses with varying levels of vitamin C to explore the feasibility of creating materials with adjustable properties. The produced hydrogels underwent comprehensive physicochemical evaluation. The findings of this examination verified the correlation between the vitamin C content and the specific characteristics of the hydrogels. It was determined from these results that the samples displayed both sorptive and antioxidative capabilities, enabling their potential application in wound dressings or other biomedical uses. A notable benefit of these hydrogels is their adaptability, allowing for modifications to achieve desired attributes tailored to particular applications.


Assuntos
Antioxidantes , Ácido Ascórbico , Hidrogéis , Extratos Vegetais , Ácido Ascórbico/química , Hidrogéis/química , Extratos Vegetais/química , Antioxidantes/química , Antioxidantes/farmacologia , Materiais Biocompatíveis/química
2.
Methods Mol Biol ; 2791: 23-33, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38532089

RESUMO

Epigenetic programming plays a vital role in regulating pluripotency genes, which become activated or inactivated during the processes of dedifferentiation and differentiation during an organism's development. The analysis of epigenetic modifications has become possible through the technique of immunostaining, where specific antibodies allow the identification of a single target protein. This chapter describes a detailed protocol for the analysis of the epigenetic modifications with the use of confocal microscopy, subsequent image, and statistical analysis on the example of Fagopyrum calli with the use of nine antibodies raised against histone H3 and H4 methylation and acetylation on several lysines as well as DNA methylation.


Assuntos
Fagopyrum , Fagopyrum/metabolismo , Histonas/metabolismo , Núcleo Celular/metabolismo , Metilação de DNA , Anticorpos/metabolismo , Epigênese Genética , Acetilação
3.
Methods Mol Biol ; 2791: 15-22, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38532088

RESUMO

Immunostaining is a well-established technique for identifying specific proteins in tissue samples with specific antibodies to identify a single target protein. It is commonly used in research and provides information about cellular localization and protein expression levels. This chapter describes a detailed protocol for immunostaining fixed Fagopyrum calli embedded in Steedman's wax using nine antibodies raised against histone H3 and H4 methylation and acetylation on several lysines and DNA methylation.


Assuntos
Fagopyrum , Fagopyrum/metabolismo , Histonas/metabolismo , Epigênese Genética , Metilação de DNA , Lisina/metabolismo , Anticorpos/metabolismo , Acetilação
4.
Environ Sci Pollut Res Int ; 31(10): 14690-14703, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38280167

RESUMO

Here, we present the results of a comprehensive study of air quality in two tunnels located in the city of Krakow, southern Poland. The study comprised three PM fractions of suspended particulate matter (PM1, PM2.5 and PM10) sampled during campaigns lasting from March 14 to April 24, 2016 and from June 28 to July 18, 2016, in the road tunnel and the tram tunnel, respectively. The collected samples had undergone comprehensive chemical, elemental and carbon isotope analyses. The results of these analyses gave the basis for better characterization of urban transport as a source of air pollution in the city. The concentrations of particulate matter varied, depending on the analysed PM fraction and the place of sampling. For the tram tunnel, the average concentrations were 53.2 µg·m-3 (PM1), 73.8 µg·m-3 (PM2.5), 96.5 µg·m-3 (PM10), to be compared with 44.2 µg·m-3, 137.7 µg·m-3, 221.5 µg·m-3, respectively, recorded in the road tunnel. The isotope-mass balance calculations carried out separately for the road and tram tunnel and for each PM fraction, revealed that 60 to 79% of carbon present in the samples collected in the road tunnel was associated with road transport, to be compared with 15-33% obtained in the tram tunnel. The second in importance were biogenic emissions (17-21% and 41-49% in the road and tram tunnel, respectively. Sixteen different polycyclic aromatic hydrocarbons (PAHs) have been identified in the analysed samples. As expected, much higher concentrations of PAHs were detected in the road tunnel when compared to the tram tunnel. Based on the analysed PAHs concentrations, health risk assessment was determined using 3 different types of indicators: carcinogenic equivalent (CEQ), mutagenic equivalent (MEQ) and toxic equivalent (TEQ).


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Hidrocarbonetos Policíclicos Aromáticos , Material Particulado/análise , Poluentes Atmosféricos/análise , Polônia , Monitoramento Ambiental/métodos , Poluição do Ar/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Emissões de Veículos/análise
5.
Molecules ; 28(20)2023 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-37894514

RESUMO

The use of natural ingredients in recent years has been of great importance in many industries and medicine. In biomedical applications, hydrogel materials also play a significant role. In view of this, the aim of this study was to synthesize and characterize hydrogel materials enriched with broadleaf linden hydrolate. An important aspect was to carry out a series of syntheses with varying types and amounts of crosslinking agents so as to test the possibility of synthesizing materials with controlled properties. The obtained hydrogels were subjected to detailed physicochemical analysis. The results of the tests confirmed the relationship between the selected properties and the type of crosslinking agent used. A crosslinking agent with a lower molar mass (575 g/mol) results in a material with a compact and strongly crosslinked structure, which is characterized by high surface roughness. The use of a crosslinking agent with a molecular weight of 700 g/mol resulted in a material with a looser-packed polymer network capable of absorbing larger amounts of liquids. The work also proved that regardless of the type of crosslinking agent used, the addition of linden hydrolate provides antioxidant properties, which is particularly important in view of the target biomedical application of such materials.

6.
Materials (Basel) ; 16(17)2023 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-37687730

RESUMO

Hydrogel materials are used in many fields of science and industry. They are of particular importance in biomedical applications. In this work, hydrogels were obtained that could act as a dressing for wounds, at the same time being a carrier of substances with antioxidant activity. The discussed materials were obtained in the field of UV radiation. The correlation between the amount of photoinitiator used and the physicochemical properties and surface morphology of the obtained materials was investigated. In addition, the hydrogels have been incorporated with wild rose extract, which is characterized by antioxidant and anti-inflammatory effects. The analysis of the sorption capacity confirmed that the obtained material is able to absorb significant amounts of incubation fluids, which, in terms of application, will enable the absorption of exudate from the wound. The highest stability of materials was noted for hydrogels obtained with the use of intermediate amounts of photoinitiator, i.e., 50 µL and 70 µL. In the case of using 20 µL or 100 µL, the photopolymerization process did not proceed properly and the obtained material was characterized by a lack of homogeneity and high brittleness. With the increase in the amount of photoinitiator, an increase in the surface roughness of hydrogel materials was confirmed. In turn, spectroscopic analysis ruled out the degradation of materials in incubation fluids, indicating the potential for their use in biomedical applications.

7.
Int J Mol Sci ; 24(12)2023 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-37373504

RESUMO

Although the influence of nanoparticles (NPs) on developmental processes is better understood, little is known about their impact on somatic embryogenesis (SE). This process involves changes in the direction of cell differentiation. Thus, studying the effect of NPs on SE is essential to reveal their impact on cell fate. This study aimed to examine the influence of gold nanoparticles (Au NPs) with different surface charges on the SE of 35S:BBM Arabidopsis thaliana, with particular emphasis on the spatiotemporal localization of pectic arabinogalactan proteins (AGPs) and extensin epitopes in cells changing the direction of their differentiation. The results show that under the influence of nanoparticles, the explant cells of 35S:BBM Arabidopsis thaliana seedling origin did not enter the path of SE. Bulges and the formation of organ-like structures were observed in these explants, in contrast to the control, where somatic embryos developed. Additionally, spatiotemporal changes in the chemical composition of the cell walls during the culture were observed. Under the influence of Au NPs, the following effects were observed: (1) explant cells did not enter the SE pathway, (2) the impacts of Au NPs with different surface charges on the explants were variable, and (3) the compositions of the analyzed pectic AGPs and extensin epitopes were diverse in the cells with different developmental programs: SE (control) and non-SE (treated with Au NPs).


Assuntos
Arabidopsis , Nanopartículas Metálicas , Arabidopsis/metabolismo , Ouro/metabolismo , Diferenciação Celular , Epitopos/metabolismo
8.
Elife ; 102021 12 23.
Artigo em Inglês | MEDLINE | ID: mdl-34939934

RESUMO

HAP2 is a transmembrane gamete fusogen found in multiple eukaryotic kingdoms and is structurally homologous to viral class II fusogens. Studies in Plasmodium have suggested that HAP2 is an attractive target for vaccines that block transmission of malaria. HAP2 has three extracellular domains, arranged in the order D2, D1, and D3. Here, we report monoclonal antibodies against the D3 fragment of Plasmodium berghei HAP2 and crystal structures of D3 in complex with Fab fragments of two of these antibodies, one of which blocks fertilization of Plasmodium berghei in vitro and transmission of malaria in mosquitoes. We also show how this Fab binds the complete HAP2 ectodomain with electron microscopy. The two antibodies cross-react with HAP2 among multiple plasmodial species. Our characterization of the Plasmodium D3 structure, HAP2 ectodomain architecture, and mechanism of inhibition provide insights for the development of a vaccine to block malaria transmission.


Assuntos
Anticorpos Monoclonais/metabolismo , Células Germinativas/imunologia , Malária/prevenção & controle , Malária/transmissão , Plasmodium berghei/imunologia , Proteínas de Protozoários/imunologia , Proteínas de Protozoários/metabolismo , Animais , Sítios de Ligação de Anticorpos , Fenômenos Biofísicos , Culicidae/parasitologia , Células Germinativas/fisiologia , Malária/imunologia , Fusão de Membrana , Ligação Proteica , Proteínas de Protozoários/química
9.
Cells ; 10(8)2021 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-34440734

RESUMO

The increased use of nanoparticles (NP) in different industries inevitably results in their release into the environment. In such conditions, plants come into direct contact with NP. Knowledge about the uptake of NP by plants and their effect on different developmental processes is still insufficient. Our studies concerned analyses of the changes in the chemical components of the cell walls of Hordeum vulgare L. roots that were grown in the presence of gold nanoparticles (AuNP). The analyses were performed using the immunohistological method and fluorescence microscopy. The obtained results indicate that AuNP with different surface charges affects the presence and distribution of selected pectic and arabinogalactan protein (AGP) epitopes in the walls of root cells.


Assuntos
Parede Celular/química , Ouro/química , Hordeum/metabolismo , Nanopartículas Metálicas/química , Hordeum/química , Hordeum/crescimento & desenvolvimento , Mucoproteínas/metabolismo , Pectinas/metabolismo , Proteínas de Plantas/metabolismo , Raízes de Plantas/química , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/metabolismo , Estresse Fisiológico
10.
Int J Mol Sci ; 22(12)2021 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-34204559

RESUMO

Recent data indicate that modifications to carotenoid biosynthesis pathway in plants alter the expression of genes affecting chemical composition of the cell wall. Phytoene synthase (PSY) is a rate limiting factor of carotenoid biosynthesis and it may exhibit species-specific and organ-specific roles determined by the presence of psy paralogous genes, the importance of which often remains unrevealed. Thus, the aim of this work was to elaborate the roles of two psy paralogs in a model system and to reveal biochemical changes in the cell wall of psy knockout mutants. For this purpose, Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR) and CRISPR associated (Cas9) proteins (CRISPR/Cas9) vectors were introduced to carotenoid-rich carrot (Daucus carota) callus cells in order to induce mutations in the psy1 and psy2 genes. Gene sequencing, expression analysis, and carotenoid content analysis revealed that the psy2 gene is critical for carotenoid biosynthesis in this model and its knockout blocks carotenogenesis. The psy2 knockout also decreased the expression of the psy1 paralog. Immunohistochemical staining of the psy2 mutant cells showed altered composition of arabinogalactan proteins, pectins, and extensins in the mutant cell walls. In particular, low-methylesterified pectins were abundantly present in the cell walls of carotenoid-rich callus in contrast to the carotenoid-free psy2 mutant. Transmission electron microscopy revealed altered plastid transition to amyloplasts instead of chromoplasts. The results demonstrate for the first time that the inhibited biosynthesis of carotenoids triggers the cell wall remodelling.


Assuntos
Vias Biossintéticas/genética , Sistemas CRISPR-Cas , Carotenoides/metabolismo , Parede Celular/metabolismo , Daucus carota/fisiologia , Edição de Genes , Sequência de Bases , Parede Celular/ultraestrutura , Daucus carota/ultraestrutura , Marcação de Genes , Genes de Plantas , Vetores Genéticos/genética , Mutação , Fenótipo , Plastídeos/genética , Plastídeos/ultraestrutura
11.
Life Sci Alliance ; 4(7)2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34135099

RESUMO

Progress towards a protective vaccine against malaria remains slow. To date, only limited protection has been routinely achieved following immunisation with either whole-parasite (sporozoite) or subunit-based vaccines. One major roadblock to vaccine progress, and to pre-erythrocytic parasite biology in general, is the continued reliance on manual salivary gland dissection for sporozoite isolation from infected mosquitoes. Here, we report development of a multi-step method, based on batch processing of homogenised whole mosquitoes, slurry, and density-gradient filtration, which combined with free-flow electrophoresis rapidly produces a pure, infective sporozoite inoculum. Human-infective Plasmodium falciparum and rodent-infective Plasmodium berghei sporozoites produced in this way are two- to threefold more infective than salivary gland dissection sporozoites in in vitro hepatocyte infection assays. In an in vivo rodent malaria model, the same P. berghei sporozoites confer sterile protection from mosquito-bite challenge when immunisation is delivered intravenously or 60-70% protection when delivered intramuscularly. By improving purity, infectivity, and immunogenicity, this method represents a key advancement in capacity to produce research-grade sporozoites, which should impact delivery of a whole-parasite based malaria vaccine at scale in the future.


Assuntos
Culicidae/parasitologia , Malária/prevenção & controle , Plasmodium berghei/patogenicidade , Plasmodium falciparum/patogenicidade , Esporozoítos/patogenicidade , Animais , Modelos Animais de Doenças , Drosophila , Células Hep G2 , Humanos , Imunização , Masculino , Ratos , Esporozoítos/crescimento & desenvolvimento
12.
Sci Rep ; 11(1): 10289, 2021 05 13.
Artigo em Inglês | MEDLINE | ID: mdl-33986416

RESUMO

There is an urgent need for high throughput, affordable methods of detecting pathogens inside insect vectors to facilitate surveillance. Near-infrared spectroscopy (NIRS) has shown promise to detect arbovirus and malaria in the laboratory but has not been evaluated in field conditions. Here we investigate the ability of NIRS to identify Plasmodium falciparum in Anopheles coluzzii mosquitoes. NIRS models trained on laboratory-reared mosquitoes infected with wild malaria parasites can detect the parasite in comparable mosquitoes with moderate accuracy though fails to detect oocysts or sporozoites in naturally infected field caught mosquitoes. Models trained on field mosquitoes were unable to predict the infection status of other field mosquitoes. Restricting analyses to mosquitoes of uninfectious and highly-infectious status did improve predictions suggesting sensitivity and specificity may be better in mosquitoes with higher numbers of parasites. Detection of infection appears restricted to homogenous groups of mosquitoes diminishing NIRS utility for detecting malaria within mosquitoes.


Assuntos
Anopheles/parasitologia , Mosquitos Vetores/parasitologia , Plasmodium falciparum/isolamento & purificação , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Animais
13.
Sci Rep ; 11(1): 1888, 2021 01 21.
Artigo em Inglês | MEDLINE | ID: mdl-33479319

RESUMO

New antimalarial therapeutics are needed to ensure that malaria cases continue to be driven down, as both emerging parasite resistance to frontline chemotherapies and mosquito resistance to current insecticides threaten control programmes. Plasmodium, the apicomplexan parasite responsible for malaria, causes disease pathology through repeated cycles of invasion and replication within host erythrocytes (the asexual cycle). Antimalarial drugs primarily target this cycle, seeking to reduce parasite burden within the host as fast as possible and to supress recrudescence for as long as possible. Intense phenotypic drug screening efforts have identified a number of promising new antimalarial molecules. Particularly important is the identification of compounds with new modes of action within the parasite to combat existing drug resistance and suitable for formulation of efficacious combination therapies. Here we detail the antimalarial properties of DDD01034957-a novel antimalarial molecule which is fast-acting and potent against drug resistant strains in vitro, shows activity in vivo, and possesses a resistance mechanism linked to the membrane transporter PfABCI3. These data support further medicinal chemistry lead-optimization of DDD01034957 as a novel antimalarial chemical class and provide new insights to further reduce in vivo metabolic clearance.


Assuntos
Antimaláricos/farmacologia , Resistência a Medicamentos/efeitos dos fármacos , Malária/tratamento farmacológico , Plasmodium falciparum/efeitos dos fármacos , Animais , Antimaláricos/química , Eritrócitos/parasitologia , Interações Hospedeiro-Parasita/efeitos dos fármacos , Humanos , Concentração Inibidora 50 , Malária/parasitologia , Camundongos , Estrutura Molecular , Plasmodium/efeitos dos fármacos , Plasmodium/parasitologia , Plasmodium berghei/efeitos dos fármacos , Plasmodium berghei/parasitologia , Plasmodium falciparum/fisiologia , Especificidade da Espécie
14.
Plant Cell Rep ; 39(6): 779-798, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32232559

RESUMO

KEY MESSAGE: Differences in the composition and the structural organisation of the extracellular matrix correlate with the morphogenic competence of the callus tissue that originated from the isolated endosperm of kiwifruit. The chemical composition and structural organisation of the extracellular matrix, including the cell wall and the layer on its surface, may correspond with the morphogenic competence of a tissue. In the presented study, this relationship was found in the callus tissue that had been differentiated from the isolated endosperm of the kiwiberry, Actinidia arguta. The experimental system was based on callus samples of exactly the same age that had originated from an isolated endosperm but were cultured under controlled conditions promoting either an organogenic or a non-organogenic pathway. The analyses which were performed using bright field, fluorescence and scanning electron microscopy techniques showed significant differences between the two types of calli. The organogenic tissue was compact and the outer walls of the peripheral cells were covered with granular structures. The non-organogenic tissue was composed of loosely attached cells, which were connected via a net-like structure. The extracellular matrices from both the non- and organogenic tissues were abundant in pectic homogalacturonan and extensins (LM19, LM20, JIM11, JIM12 and JIM20 epitopes), but the epitopes that are characteristic for rhamnogalacturonan I (LM5 and LM6), hemicellulose (LM25) and the arabinogalactan protein (LM2) were detected only in the non-organogenic callus. Moreover, we report the epitopes, which presence is characteristic for the Actinidia endosperm (LM21 and LM25, heteromannan and xyloglucan) and for the endosperm-derived cells that undergo dedifferentiation (loss of LM21 and LM25; appearance or increase in the content of LM5, LM6, LM19, JIM11, JIM12, JIM20, JIM8 and JIM16 epitopes).


Assuntos
Actinidia/citologia , Actinidia/metabolismo , Matriz Extracelular/química , Matriz Extracelular/metabolismo , Anticorpos Monoclonais , Calo Ósseo/citologia , Parede Celular/química , Parede Celular/ultraestrutura , Endosperma , Epitopos , Matriz Extracelular/ultraestrutura , Frutas , Glucanos , Imuno-Histoquímica , Microscopia Eletrônica de Varredura , Mucoproteínas , Pectinas , Proteínas de Plantas , Polissacarídeos , Xilanos
15.
Sci Rep ; 9(1): 18300, 2019 12 04.
Artigo em Inglês | MEDLINE | ID: mdl-31797966

RESUMO

Inhibiting transmission of Plasmodium is an essential strategy in malaria eradication, and the biological process of gamete fusion during fertilization is a proven target for this approach. Lack of knowledge of the mechanisms underlying fertilization have been a hindrance in the development of transmission-blocking interventions. Here we describe a protein disulphide isomerase essential for malarial transmission (PDI-Trans/PBANKA_0820300) to the mosquito. We show that PDI-Trans activity is male-specific, surface-expressed, essential for fertilization/transmission, and exhibits disulphide isomerase activity which is up-regulated post-gamete activation. We demonstrate that PDI-Trans is a viable anti-malarial drug and vaccine target blocking malarial transmission with the use of PDI inhibitor bacitracin (98.21%/92.48% reduction in intensity/prevalence), and anti-PDI-Trans antibodies (66.22%/33.16% reduction in intensity/prevalence). To our knowledge, these results provide the first evidence that PDI function is essential for malarial transmission, and emphasize the potential of anti-PDI agents to act as anti-malarials, facilitating the future development of novel transmission-blocking interventions.


Assuntos
Antimaláricos , Bacitracina , Vacinas Antimaláricas , Malária , Plasmodium berghei/enzimologia , Isomerases de Dissulfetos de Proteínas/fisiologia , Animais , Antimaláricos/farmacologia , Antimaláricos/uso terapêutico , Bacitracina/farmacologia , Bacitracina/uso terapêutico , Feminino , Malária/prevenção & controle , Malária/transmissão , Vacinas Antimaláricas/farmacologia , Vacinas Antimaláricas/uso terapêutico , Masculino , Camundongos , Plasmodium berghei/efeitos dos fármacos , Plasmodium berghei/patogenicidade , Proteínas de Protozoários/fisiologia
16.
Int J Mol Sci ; 20(10)2019 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-31130622

RESUMO

Plants frequently encounter diverse abiotic stresses, one of which is environmental thermal stress. To cope with these stresses, plants have developed a range of mechanisms, including altering the cell wall architecture, which is facilitated by the arabinogalactan proteins (AGP) and extensins (EXT). In order to characterise the localisation of the epitopes of the AGP and EXT, which are induced by the stress connected with a low (4 °C) or a high (40 °C) temperature, in the leaves of Brachypodium distachyon, we performed immunohistochemical analyses using the antibodies that bind to selected AGP (JIM8, JIM13, JIM16, LM2 and MAC207), pectin/AGP (LM6) as well as EXT (JIM11, JIM12 and JIM20). The analyses of the epitopes of the AGP indicated their presence in the phloem and in the inner bundle sheath (JIM8, JIM13, JIM16 and LM2). The JIM16 epitope was less abundant in the leaves from the low or high temperature compared to the control leaves. The LM2 epitope was more abundant in the leaves that had been subjected to the high temperatures. In the case of JIM13 and MAC207, no changes were observed at the different temperatures. The epitopes of the EXT were primarily observed in the mesophyll and xylem cells of the major vascular bundle (JIM11, JIM12 and JIM20) and no correlation was observed between the presence of the epitopes and the temperature stress. We also analysed changes in the level of transcript accumulation of some of the genes encoding EXT, EXT-like receptor kinases and AGP in the response to the temperature stress. In both cases, although we observed the upregulation of the genes encoding AGP in stressed plants, the changes were more pronounced at the high temperature. Similar changes were observed in the expression profiles of the EXT and EXT-like receptor kinase genes. Our findings may be relevant for genetic engineering of plants with increased resistance to the temperature stress.


Assuntos
Brachypodium/metabolismo , Glicoproteínas/metabolismo , Hidroxiprolina/metabolismo , Folhas de Planta/metabolismo , Proteínas de Plantas/metabolismo , Brachypodium/genética , Resposta ao Choque Frio , Regulação da Expressão Gênica de Plantas , Glicoproteínas/genética , Resposta ao Choque Térmico , Hidroxiprolina/genética , Mucoproteínas/genética , Mucoproteínas/metabolismo , Folhas de Planta/genética , Proteínas de Plantas/genética
17.
BMC Plant Biol ; 19(1): 151, 2019 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-30999851

RESUMO

BACKGROUND: Grafting is a technique widely used in horticulture. The processes involved in grafting are diverse, and the technique is commonly employed in studies focusing on the mechanisms that regulate cell differentiation or response of plants to abiotic stress. Information on the changes in the composition of the cell wall that occur during the grafting process is scarce. Therefore, this study was carried out for analyzing the composition of the cell wall using Arabidopsis hypocotyls as an example. During the study, the formation of a layer that covers the surface of the graft union was observed. So, this study also aimed to describe the histological and cellular changes that accompany autografting of Arabidopsis hypocotyls and to perform preliminary chemical and structural analyses of extracellular material that seals the graft union. RESULTS: During grafting, polyphenolic and lipid compounds were detected, along with extracellular deposition of carbohydrate/protein material. The spatiotemporal changes observed in the structure of the extracellular material included the formation of a fibrillar network, polymerization of the fibrillar network into a membranous layer, and the presence of bead-like structures on the surface of cells in established graft union. These bead-like structures appeared either "closed" or "open". Only three cell wall epitopes, namely: LM19 (un/low-methyl-esterified homogalacturonan), JIM11, and JIM20 (extensins), were detected abundantly on the cut surfaces that made the adhesion plane, as well as in the structure that covered the graft union and in the bead-like structures, during the subsequent stages of regeneration. CONCLUSIONS: To the best of our knowledge, this is the first report on the composition and structure of the extracellular material that gets deposited on the surface of graft union during Arabidopsis grafting. The results showed that unmethyl-esterified homogalacturonan and extensins are together involved in the adhesion of scion and stock, as well as taking part in sealing the graft union. The extracellular material is of importance not only due to the potential pectin-extensin interaction but also due to its origin. The findings presented here implicate a need for studies with biochemical approach for a detailed analysis of the composition and structure of the extracellular material.


Assuntos
Arabidopsis/fisiologia , Glicoproteínas/metabolismo , Pectinas/metabolismo , Proteínas de Plantas/metabolismo , Arabidopsis/anatomia & histologia , Arabidopsis/citologia , Arabidopsis/ultraestrutura , Parede Celular/metabolismo , Epitopos/metabolismo , Esterificação , Hipocótilo/citologia , Hipocótilo/fisiologia , Hipocótilo/ultraestrutura
19.
Elife ; 72018 06 19.
Artigo em Inglês | MEDLINE | ID: mdl-29914622

RESUMO

Anti-malarial pre-erythrocytic vaccines (PEV) target transmission by inhibiting human infection but are currently partially protective. It has been posited, but never demonstrated, that co-administering transmission-blocking vaccines (TBV) would enhance malaria control. We hypothesized a mechanism that TBV could reduce parasite density in the mosquito salivary glands, thereby enhancing PEV efficacy. This was tested using a multigenerational population assay, passaging Plasmodium berghei to Anopheles stephensi mosquitoes. A combined efficacy of 90.8% (86.7-94.2%) was observed in the PEV +TBV antibody group, higher than the estimated efficacy of 83.3% (95% CrI 79.1-87.0%) if the two antibodies acted independently. Higher PEV efficacy at lower mosquito parasite loads was observed, comprising the first direct evidence that co-administering anti-sporozoite and anti-transmission interventions act synergistically, enhancing PEV efficacy across a range of TBV doses and transmission intensities. Combining partially effective vaccines of differing anti-parasitic classes is a pragmatic, powerful way to accelerate malaria elimination efforts.


Assuntos
Anticorpos Bloqueadores/administração & dosagem , Anticorpos Monoclonais/administração & dosagem , Anticorpos Antiprotozoários/administração & dosagem , Vacinas Antimaláricas/administração & dosagem , Malária/prevenção & controle , Plasmodium berghei/imunologia , Esporozoítos/imunologia , Animais , Anopheles/parasitologia , Sinergismo Farmacológico , Feminino , Humanos , Malária/imunologia , Malária/parasitologia , Camundongos , Mosquitos Vetores/parasitologia , Carga Parasitária , Plasmodium berghei/efeitos dos fármacos , Proteínas de Protozoários/genética , Proteínas de Protozoários/imunologia , Glândulas Salivares/parasitologia , Esporozoítos/química , Trofozoítos/química , Trofozoítos/imunologia
20.
Sci Rep ; 8(1): 3896, 2018 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-29497047

RESUMO

With the increasing prevalence of artemisinin-resistant malaria parasites, a highly efficacious and durable vaccine for malaria is urgently required. We have developed an experimental virus-vectored vaccine platform based on an envelope-modified baculovirus dual-expression system (emBDES). Here, we show a conceptually new vaccine platform based on an adenovirus-prime/emBDES-boost heterologous immunization regimen expressing the Plasmodium falciparum circumsporozoite protein (PfCSP). A human adenovirus 5-prime/emBDES-boost heterologous immunization regimen consistently achieved higher sterile protection against transgenic P. berghei sporozoites expressing PfCSP after a mosquito-bite challenge than reverse-ordered or homologous immunization. This high protective efficacy was also achieved with a chimpanzee adenovirus 63-prime/emBDES-boost heterologous immunization regimen against an intravenous sporozoite challenge. Thus, we show that the adenovirus-prime/emBDES-boost heterologous immunization regimen confers sterile protection against sporozoite challenge by two individual routes, providing a promising new malaria vaccine platform for future clinical use.


Assuntos
Vacinas Antimaláricas/imunologia , Esporozoítos/imunologia , Vacinação/métodos , Adenoviridae/imunologia , Infecções por Adenoviridae , Animais , Anticorpos Antiprotozoários/imunologia , Antígenos de Protozoários/imunologia , Baculoviridae/imunologia , Modelos Animais de Doenças , Feminino , Imunização/métodos , Imunização Secundária/métodos , Malária/imunologia , Malária Falciparum/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Plasmodium falciparum/genética , Proteínas de Protozoários/genética , Vacinas de DNA/imunologia
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