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1.
Chem Res Toxicol ; 33(5): 1215-1225, 2020 05 18.
Artigo em Inglês | MEDLINE | ID: mdl-32088960

RESUMO

The number of consumer products containing nanoparticles (NPs) experienced a rapid increase during the past decades. However, most studies of nanosafety have been conducted using only pure NPs produced in the laboratory, while the interactions with other ingredients in consumer products have rarely been considered so far. In the present study, we investigated such interactions-with a special focus on modern lifestyle products (MLPs) used by adolescents. An extensive survey was undertaken at different high schools all over Austria to identify MLPs that either contain NPs or that could come easily in contact with NPs from other consumer products (such as TiO2 from sunscreens). Based on the results from a survey among secondary schools students, we focused on ingredients from Henna tattoos (2-hydroxy-1,4-naphtoquinone, HNQ, and p-phenylenediamine, PPD), fragrances (butylphenyl methylpropional, known as Lilial), cosmetics and skin-care products (four different parabens). As a cellular model, we decided to use neonatal normal human dermal fibroblasts (nNHDF), since skin contact is the main route of exposure for these compounds. TiO2 NPs interacted with these compounds as evidenced by alterations in their hydrodynamic diameter observed by nanoparticle tracking analysis. Combinations of TiO2 NPs with the different MLP components did not show altered cytotoxicity profiles compared to MLP components without TiO2 NPs. Nevertheless, altered cellular glutathione contents were detected after incubation of the cells with Lilial. This effect was independent of the presence of TiO2 NPs. Testing mixtures of NPs with other compounds from consumer products is an important approach to achieve a more reliable safety assessment.


Assuntos
Cosméticos/farmacologia , Fibroblastos/efeitos dos fármacos , Estilo de Vida , Nanopartículas/química , Pele/efeitos dos fármacos , Titânio/química , Adolescente , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Cosméticos/química , Relação Dose-Resposta a Droga , Humanos , Tamanho da Partícula
2.
Cell Mol Life Sci ; 76(10): 2003-2013, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30747251

RESUMO

To successfully feed, ticks inject pharmacoactive molecules into the vertebrate host including cystatin cysteine protease inhibitors. However, the molecular and cellular events modulated by tick saliva remain largely unknown. Here, we describe and characterize a novel immunomodulatory cystatin, Iristatin, which is upregulated in the salivary glands of feeding Ixodes ricinus ticks. We present the crystal structure of Iristatin at 1.76 Å resolution. Purified recombinant Iristatin inhibited the proteolytic activity of cathepsins L and C and diminished IL-2, IL-4, IL-9, and IFN-γ production by different T-cell populations, IL-6 and IL-9 production by mast cells, and nitric oxide production by macrophages. Furthermore, Iristatin inhibited OVA antigen-induced CD4+ T-cell proliferation and leukocyte recruitment in vivo and in vitro. Our results indicate that Iristatin affects wide range of anti-tick immune responses in the vertebrate host and may be exploitable as an immunotherapeutic.


Assuntos
Proteínas de Artrópodes/farmacologia , Cistatinas/farmacologia , Imunossupressores/farmacologia , Cistatinas Salivares/farmacologia , Sequência de Aminoácidos , Animais , Proteínas de Artrópodes/química , Proteínas de Artrópodes/genética , Cristalografia por Raios X , Cistatinas/classificação , Cistatinas/genética , Citocinas/metabolismo , Compostos de Epóxi/metabolismo , Feminino , Imunossupressores/química , Imunossupressores/metabolismo , Ixodes/química , Ixodes/genética , Ixodes/metabolismo , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Óxido Nítrico/metabolismo , Filogenia , Proteólise/efeitos dos fármacos , Cistatinas Salivares/química , Cistatinas Salivares/genética , Homologia de Sequência de Aminoácidos , Linfócitos T/efeitos dos fármacos , Linfócitos T/metabolismo , Tirosina/análogos & derivados , Tirosina/metabolismo
3.
Aten. prim. (Barc., Ed. impr.) ; 50(8): 486-492, oct. 2018. tab, graf
Artigo em Espanhol | IBECS | ID: ibc-179132

RESUMO

OBJETIVO: Evaluar el grado en que los sucesos adversos (SA) ligados a la asistencia sanitaria alcanzan al paciente y su severidad. Analizar los factores contribuyentes a la aparición de SA, la relación con el daño provocado y el grado de evitabilidad. DISEÑO: Estudio descriptivo retrospectivo. Emplazamiento: Servicio de Atención Primaria de Porriño desde enero de 2014 a abril de 2016. Participantes y/o contexto: Se incluyeron notificaciones de SA en el Sistema de Notificación y Aprendizaje para Seguridad del Paciente (SiNASP). MÉTODO: Variables de medida: incidente adverso (IA) si no alcanzó al paciente o no produjo daño, evento adverso (EA) si llegó al paciente con daño. Grado de daño clasificado como mínimo, menor, moderado, crítico y catastrófico. Evitabilidad registrada como escasa evidencia de ser evitable, 50% evitable y sólida evidencia de ser evitable. nálisis de datos: porcentajes y test de chi-cuadrado para variables cualitativas; p < 0,05 con SPSS.15 Fuente de datos: SiNASP. Consideraciones éticas: autorizado por el Comité de Ética de Investigación (2016/344). RESULTADOS: Se registraron 166 SA (50,0% hombres, 46,4% mujeres; edad media: 60,80 años). El 62,7% alcanzaron al paciente. EA: 45,8% produjeron daño mínimo y 2,4%, daño crítico. Los profesionales fueron factor contribuyente en el 71,7% de los EA, encontrándose tendencia a la asociación entre deficiente comunicación y ausencia de protocolos con el daño producido. Grado de evitabilidad: 96,4%. CONCLUSIONES: La mayoría de los SA alcanzaron al paciente, estando relacionados con la medicación, pruebas diagnósticas y errores de laboratorio. El grado de daño se asoció con problemas de comunicación, ausencia o deficiencia de protocolos y escasa cultura en seguridad


OBJECTIVE: To assess the extent of healthcare related adverse events (AEs), their effect on patients, and their seriousness. To analyse the factors leading to the development of AEs, their relationship with the damage caused, and their degree of preventability. DESIGN: Retrospective descriptive study. LOCATION: Porriño, Pontevedra, Spain, Primary Care Service, from January-2014 to April-2016. Participants and/or context: Reported AEs were entered into the Patient Safety Reporting and Learning System (SiNASP). METHOD: The variables measured were: Near Incident (NI) an occurrence with no effect or harm on the patient; Adverse Event (AE) an occurrence that affects or harms a patient. The level of harm is classified as minimal, minor, moderate, critical, and catastrophic. Preventability was classified as little evidence of being preventable, 50% preventable, and sound evidence of being preventable. Data analysis: percentages and Chi-squared test for qualitative variables; P < .05 with SPSS.15. Data source: SiNASP. Ethical considerations: approved by the Research Ethics Committee (2016/344). RESULTS: There were 166 recorded AEs (50.6% in males, and 46.4% in women. The mean age was 60.80 years). Almost two-thirds 62.7% of AEs affected the patient, with 45.8% causing minimal damage, while 2.4% caused critical damages. Healthcare professionals were a contributing factor in 71.7% of the AEs, with the trend showing that poor communication and lack of protocols were related to the damage caused. Degree of preventability: 96.4%. CONCLUSIONS: Most AEs affected the patient, and were related to medication, diagnostic tests, and laboratory errors. The level of harm was related to communication problems, lack of, or deficient, protocols and a poor safety culture


Assuntos
Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Segurança do Paciente/estatística & dados numéricos , Segurança do Paciente/normas , Atenção Primária à Saúde , Fatores de Risco , Estudos Retrospectivos , Notificação de Doenças
4.
Aten Primaria ; 50(8): 486-492, 2018 10.
Artigo em Espanhol | MEDLINE | ID: mdl-29183678

RESUMO

OBJECTIVE: To assess the extent of healthcare related adverse events (AEs), their effect on patients, and their seriousness. To analyse the factors leading to the development of AEs, their relationship with the damage caused, and their degree of preventability. DESIGN: Retrospective descriptive study. LOCATION: Porriño, Pontevedra, Spain, Primary Care Service, from January-2014 to April-2016. PARTICIPANTS AND/OR CONTEXT: Reported AEs were entered into the Patient Safety Reporting and Learning System (SiNASP). METHOD: The variables measured were: Near Incident (NI) an occurrence with no effect or harm on the patient; Adverse Event (AE) an occurrence that affects or harms a patient. The level of harm is classified as minimal, minor, moderate, critical, and catastrophic. Preventability was classified as little evidence of being preventable, 50% preventable, and sound evidence of being preventable. DATA ANALYSIS: percentages and Chi-squared test for qualitative variables; P<.05 with SPSS.15. DATA SOURCE: SiNASP. Ethical considerations: approved by the Research Ethics Committee (2016/344). RESULTS: There were 166 recorded AEs (50.6% in males, and 46.4% in women. The mean age was 60.80years). Almost two-thirds 62.7% of AEs affected the patient, with 45.8% causing minimal damage, while 2.4% caused critical damages. Healthcare professionals were a contributing factor in 71.7% of the AEs, with the trend showing that poor communication and lack of protocols were related to the damage caused. Degree of preventability: 96.4%. CONCLUSIONS: Most AEs affected the patient, and were related to medication, diagnostic tests, and laboratory errors. The level of harm was related to communication problems, lack of, or deficient, protocols and a poor safety culture.


Assuntos
Erros Médicos/efeitos adversos , Segurança do Paciente , Comunicação , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/complicações , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/epidemiologia , Feminino , Pessoal de Saúde/estatística & dados numéricos , Humanos , Masculino , Erros Médicos/classificação , Erros Médicos/prevenção & controle , Erros Médicos/estatística & dados numéricos , Pessoa de Meia-Idade , Atenção Primária à Saúde , Estudos Retrospectivos , Fatores de Risco , Espanha
5.
Microb Ecol ; 75(4): 888-902, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29080101

RESUMO

Phenanthrene mineralisation studies in both pristine and contaminated sandy soils were undertaken through detailed assessment of the activity and diversity of the microbial community. Stable isotope probing (SIP) was used to assess and identify active 13C-labelled phenanthrene degraders. Baseline profiling indicated that there was little difference in fungal diversity but a significant difference in bacterial diversity dependent on contamination history. Identification of dominant fungal and bacterial species highlighted the presence of organisms capable of degrading various petroleum-based compounds together with other anthropogenic compounds, regardless of contamination history. Community response following a simulated contamination event (14C-phenanthrene) showed that the microbial community in deep pristine and shallow contaminated soils adapted most to the presence of phenanthrene. The similarity in microbial community structure of well-adapted soils demonstrated that a highly adaptable fungal community in these soils enabled a rapid response to the introduction of a contaminant. Ten fungal and 15 bacterial species were identified as active degraders of phenanthrene. The fungal degraders were dominated by the phylum Basidiomycota including the genus Crypotococcus, Cladosporium and Tremellales. Bacterial degraders included the genera Alcanivorax, Marinobacter and Enterococcus. There was little synergy between dominant baseline microbes, predicted degraders and those that were determined to be actually degrading the contaminant. Overall, assessment of baseline microbial community in contaminated soils provides useful information; however, additional laboratory assessment of the microbial community's ability to degrade pollutants allows for better prediction of the bioremediation potential of a soil.


Assuntos
Compostos de Bifenilo/metabolismo , Carbamatos/metabolismo , Microbiota/fisiologia , Niacinamida/análogos & derivados , Fenantrenos/metabolismo , Pirazóis/metabolismo , Microbiologia do Solo , Poluentes do Solo/metabolismo , Bactérias/classificação , Bactérias/genética , Bactérias/metabolismo , Biodegradação Ambiental , Biodiversidade , Fungos/classificação , Fungos/genética , Fungos/metabolismo , Genes de RNAr/genética , Marcação por Isótopo/métodos , Microbiota/genética , Niacinamida/metabolismo , Filogenia , Hidrocarbonetos Policíclicos Aromáticos/metabolismo , Solo
6.
RNA ; 23(8): 1259-1269, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28473453

RESUMO

The hard tick Ixodes ricinus is an important disease vector whose salivary secretions mediate blood-feeding success on vertebrate hosts, including humans. Here we describe the expression profiles and downstream analysis of de novo-discovered microRNAs (miRNAs) expressed in I. ricinus salivary glands and saliva. Eleven tick-derived libraries were sequenced to produce 67,375,557 Illumina reads. De novo prediction yielded 67 bona fide miRNAs out of which 35 are currently not present in miRBase. We report for the first time the presence of microRNAs in tick saliva, obtaining furthermore molecular indicators that those might be of exosomal origin. Ten out of these microRNAs are at least 100 times more represented in saliva. For the four most expressed microRNAs from this subset, we analyzed their combinatorial effects upon their host transcriptome using a novel in silico target network approach. We show that only the inclusion of combinatorial effects reveals the functions in important pathways related to inflammation and pain sensing. A control set of highly abundant microRNAs in both saliva and salivary glands indicates no significant pathways and a far lower number of shared target genes. Therefore, the analysis of miRNAs from pure tick saliva strongly supports the hypothesis that tick saliva miRNAs can modulate vertebrate host homeostasis and represents the first direct evidence of tick miRNA-mediated regulation of vertebrate host gene expression at the tick-host interface. As such, the herein described miRNAs may support future drug discovery and development projects that will also experimentally question their predicted molecular targets in the vertebrate host.


Assuntos
Redes Reguladoras de Genes , Interações Hospedeiro-Parasita/genética , Ixodes/genética , MicroRNAs/análise , Saliva/química , Infestações por Carrapato/parasitologia , Transcriptoma , Animais , Simulação por Computador , Sequenciamento de Nucleotídeos em Larga Escala/métodos , MicroRNAs/genética , Saliva/metabolismo , Glândulas Salivares/metabolismo , Infestações por Carrapato/genética , Vertebrados/parasitologia
7.
Amino Acids ; 48(7): 1695-706, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27129464

RESUMO

Nitric oxide (NO), S-nitrosoglutathione (GSNO) and S-nitrosocysteine are highly potent signaling molecules, acting both by cGMP-dependent and cGMP-independent mechanisms. The NO metabolite nitrite (NO2 (-)) is a major NO reservoir. Hemoglobin, xanthine oxidoreductase and carbonic anhydrase (CA) have been reported to reduce/convert nitrite to NO. We evaluated the role and the physiological importance of CA for an extra-platelet CA/nitrite/NO/cGMP pathway in human platelets. Authentic NO was analyzed by an NO-sensitive electrode. GSNO and GS(15)NO were measured by liquid chromatography-tandem mass spectrometry (LC-MS/MS). cGMP was determined by LC-MS/MS or RIA. In reduced glutathione (GSH) containing aqueous buffer (pH 7.4), human and bovine erythrocytic CAII-mediated formation of GSNO from nitrite and GS(15)NO from (15)N-nitrite. In the presence of L-cysteine and GSH, this reaction was accompanied by NO release. Incubation of nitrite with bovine erythrocytic CAII and recombinant soluble guanylyl cyclase resulted in cGMP formation. Upon incubation of nitrite with bovine erythrocytic CAII and washed human platelets, cGMP and P-VASP(S239) were formed in the platelets. This study provides the first evidence that extra-platelet nitrite and erythrocytic CAII may modulate platelet function in a cGMP-dependent manner. The new nitrite-dependent CA activity may be a general principle and explain the cardioprotective effects of inorganic nitrite in the vasculature. We propose that nitrous acid (ONOH) is the primary CA-catalyzed reaction product of nitrite.


Assuntos
Plaquetas/enzimologia , Anidrase Carbônica II , Eritrócitos/enzimologia , Nitritos , Compostos Nitrosos , Guanilil Ciclase Solúvel , Compostos de Sulfidrila , Animais , Anidrase Carbônica II/química , Anidrase Carbônica II/metabolismo , Bovinos , Humanos , Nitritos/química , Nitritos/metabolismo , Compostos Nitrosos/síntese química , Compostos Nitrosos/química , Compostos Nitrosos/metabolismo , Guanilil Ciclase Solúvel/química , Guanilil Ciclase Solúvel/metabolismo , Compostos de Sulfidrila/química , Compostos de Sulfidrila/metabolismo
8.
J Med Entomol ; 52(3): 351-8, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-26334808

RESUMO

Saliva of blood-sucking arthropods contains a complex cocktail of pharmacologically active compounds that assists feeding by counteracting their hosts' hemostatic and inflammatory reactions. Panstrongylus megistus (Burmeister) is an important vector of Chagas disease in South America, but despite its importance there is only one salivary protein sequence publicly deposited in GenBank. In the present work, we used Illumina technology to disclose and publicly deposit 3,703 coding sequences obtained from the assembly of >70 million reads. These sequences should assist proteomic experiments aimed at identifying pharmacologically active proteins and immunological markers of vector exposure. A supplemental file of the transcriptome and deducted protein sequences can be obtained from http://exon.niaid.nih.gov/transcriptome/P_megistus/Pmeg-web.xlsx.


Assuntos
Proteínas de Insetos/genética , Panstrongylus/genética , Proteínas e Peptídeos Salivares/genética , Sialoglicoproteínas/genética , Animais , Proteínas de Insetos/metabolismo , Dados de Sequência Molecular , Ninfa/genética , Ninfa/crescimento & desenvolvimento , Ninfa/metabolismo , Panstrongylus/crescimento & desenvolvimento , Panstrongylus/metabolismo , Filogenia , Proteômica , Saliva/química , Proteínas e Peptídeos Salivares/metabolismo , Sialoglicoproteínas/metabolismo
9.
Sci Rep ; 5: 9103, 2015 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-25765539

RESUMO

Ixodes ricinus is a tick that transmits the pathogens of Lyme and several arboviral diseases. Pathogens invade the tick midgut, disseminate through the hemolymph, and are transmitted to the vertebrate host via the salivary glands; subverting these processes could be used to interrupt pathogen transfer. Here, we use massive de novo sequencing to characterize the transcriptional dynamics of the salivary and midgut tissues of nymphal and adult I. ricinus at various time points after attachment on the vertebrate host. Members of a number of gene families show stage- and time-specific expression. We hypothesize that gene expression switching may be under epigenetic control and, in support of this, identify 34 candidate proteins that modify histones. I. ricinus-secreted proteins are encoded by genes that have a non-synonymous to synonymous mutation rate even greater than immune-related genes. Midgut transcriptome (mialome) analysis reveals several enzymes associated with protein, carbohydrate, and lipid digestion, transporters and channels that might be associated with nutrient uptake, and immune-related transcripts including antimicrobial peptides. This publicly available dataset supports the identification of protein and gene targets for biochemical and physiological studies that exploit the transmission lifecycle of this disease vector for preventative and therapeutic purposes.


Assuntos
Mucosa Intestinal/metabolismo , Ixodes/genética , Glândulas Salivares/metabolismo , Transcrição Gênica , Animais , Análise por Conglomerados , Biologia Computacional , Perfilação da Expressão Gênica , Ixodes/classificação , Anotação de Sequência Molecular , Especificidade de Órgãos/genética , Filogenia , Polimorfismo Genético , Fatores de Tempo , Transcriptoma
10.
PLoS Negl Trop Dis ; 8(12): e3372, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25474469

RESUMO

BACKGROUND: Triatoma infestans is the main vector of Chagas disease in South America. As in all hematophagous arthropods, its saliva contains a complex cocktail that assists blood feeding by preventing platelet aggregation and blood clotting and promoting vasodilation. These salivary components can be immunologically recognized by their vector's hosts and targeted with antibodies that might disrupt blood feeding. These antibodies can be used to detect vector exposure using immunoassays. Antibodies may also contribute to the fast evolution of the salivary cocktail. METHODOLOGY: Salivary gland cDNA libraries from nymphal and adult T. infestans of breeding colonies originating from different locations (Argentina, Chile, Peru and Bolivia), and cDNA libraries originating from F1 populations of Bolivia, were sequenced using Illumina technology. Coding sequences (CDS) were extracted from the assembled reads, the numbers of reads mapped to these CDS, sequences were functionally annotated and polymorphisms determined. MAIN FINDINGS/SIGNIFICANCE: Over five thousand CDS, mostly full length or near full length, were publicly deposited on GenBank. Transcripts that were over 10-fold overexpressed from different geographical regions, or from different developmental stages were identified. Polymorphisms were mapped to derived coding sequences, and found to vary between developmental instars and geographic origin of the biological material. This expanded sialome database from T. infestans should be of assistance in future proteomic work attempting to identify salivary proteins that might be used as epidemiological markers of vector exposure, or proteins of pharmacological interest.


Assuntos
Biblioteca Gênica , Saliva/química , Proteínas e Peptídeos Salivares/genética , Transcriptoma/genética , Triatoma/genética , Animais , Proteínas e Peptídeos Salivares/metabolismo , América do Sul , Triatoma/metabolismo
12.
Mol Cell Proteomics ; 13(10): 2725-35, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25048707

RESUMO

Although pathogens are usually transmitted within the first 24-48 h of attachment of the castor bean tick Ixodes ricinus, little is known about the tick's biological responses at these earliest phases of attachment. Tick midgut and salivary glands are the main tissues involved in tick blood feeding and pathogen transmission but the limited genomic information for I. ricinus delays the application of high-throughput methods to study their physiology. We took advantage of the latest advances in the fields of Next Generation RNA-Sequencing and Label-free Quantitative Proteomics to deliver an unprecedented, quantitative description of the gene expression dynamics in the midgut and salivary glands of this disease vector upon attachment to the vertebrate host. A total of 373 of 1510 identified proteins had higher expression in the salivary glands, but only 110 had correspondingly high transcript levels in the same tissue. Furthermore, there was midgut-specific expression of 217 genes at both the transcriptome and proteome level. Tissue-dependent transcript, but not protein, accumulation was revealed for 552 of 885 genes. Moreover, we discovered the enrichment of tick salivary glands in proteins involved in gene transcription and translation, which agrees with the secretory role of this tissue; this finding also agrees with our finding of lower tick t-RNA representation in the salivary glands when compared with the midgut. The midgut, in turn, is enriched in metabolic components and proteins that support its mechanical integrity in order to accommodate and metabolize the ingested blood. Beyond understanding the physiological events that support hematophagy by arthropod ectoparasites, we discovered more than 1500 proteins located at the interface between ticks, the vertebrate host, and the tick-borne pathogens. Thus, our work significantly improves the knowledge of the genetics underlying the transmission lifecycle of this tick species, which is an essential step for developing alternative methods to better control tick-borne diseases.


Assuntos
Perfilação da Expressão Gênica/métodos , Ixodes/crescimento & desenvolvimento , Proteômica/métodos , Glândulas Salivares/metabolismo , Animais , Feminino , Trato Gastrointestinal/metabolismo , Regulação da Expressão Gênica , Ixodes/anatomia & histologia , Ixodes/genética , Estágios do Ciclo de Vida , Masculino , Dados de Sequência Molecular , Especificidade de Órgãos , RNA de Transferência/metabolismo
13.
PLoS Negl Trop Dis ; 8(4): e2783, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24699441

RESUMO

BACKGROUND: Salivary proteins of Triatoma infestans elicit humoral immune responses in their vertebrate hosts. These immune responses indicate exposure to triatomines and thus can be a useful epidemiological tool to estimate triatomine infestation. In the present study, we analyzed antibody responses of guinea pigs to salivary antigens of different developmental stages of four T. infestans strains originating from domestic and/or peridomestic habitats in Argentina, Bolivia, Chile and Peru. We aimed to identify developmental stage- and strain-specific salivary antigens as potential markers of T. infestans exposure. METHODOLOGY AND PRINCIPAL FINDINGS: In SDS-PAGE analysis of salivary proteins of T. infestans the banding pattern differed between developmental stages and strains of triatomines. Phenograms constructed from the salivary profiles separated nymphal instars, especially the 5th instar, from adults. To analyze the influence of stage- and strain-specific differences in T. infestans saliva on the antibody response of guinea pigs, twenty-one guinea pigs were exposed to 5th instar nymphs and/or adults of different T. infestans strains. Western blot analyses using sera of exposed guinea pigs revealed stage- and strain-specific variations in the humoral response of animals. In total, 27 and 17 different salivary proteins reacted with guinea pig sera using IgG and IgM antibodies, respectively. Despite all variations of recognized salivary antigens, an antigen of 35 kDa reacted with sera of almost all challenged guinea pigs. CONCLUSION: Salivary antigens are increasingly considered as an epidemiological tool to measure exposure to hematophagous arthropods, but developmental stage- and strain-specific variations in the saliva composition and the respective differences of immunogenicity are often neglected. Thus, the development of a triatomine exposure marker for surveillance studies after triatomine control campaigns requires detailed investigations. Our study resulted in the identification of a potential antigen as useful marker of T. infestans exposure.


Assuntos
Anticorpos/sangue , Biomarcadores/sangue , Mordeduras e Picadas/imunologia , Proteínas de Insetos/imunologia , Proteínas e Peptídeos Salivares/imunologia , Triatoma , Animais , Western Blotting , Eletroforese em Gel de Poliacrilamida , Feminino , Cobaias , Masculino , Proteoma/análise , Proteínas e Peptídeos Salivares/análise , América do Sul
14.
BMC Evol Biol ; 14: 4, 2014 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-24397261

RESUMO

BACKGROUND: Ticks are blood-sucking arthropods and a primary function of tick salivary proteins is to counteract the host's immune response. Tick salivary Kunitz-domain proteins perform multiple functions within the feeding lesion and have been classified as venoms; thereby, constituting them as one of the important elements in the arms race with the host. The two main mechanisms advocated to explain the functional heterogeneity of tick salivary Kunitz-domain proteins are gene sharing and gene duplication. Both do not, however, elucidate the evolution of the Kunitz family in ticks from a structural dynamic point of view. The Red Queen hypothesis offers a fruitful theoretical framework to give a dynamic explanation for host-parasite interactions. Using the recent salivary gland Ixodes ricinus transcriptome we analyze, for the first time, single Kunitz-domain encoding transcripts by means of computational, structural bioinformatics and phylogenetic approaches to improve our understanding of the structural evolution of this important multigenic protein family. RESULTS: Organizing the I. ricinus single Kunitz-domain peptides based on their cysteine motif allowed us to specify a putative target and to relate this target specificity to Illumina transcript reads during tick feeding. We observe that several of these Kunitz peptide groups vary in their translated amino acid sequence, secondary structure, antigenicity, and intrinsic disorder, and that the majority of these groups are subject to a purifying (negative) selection. We finalize by describing the evolution and emergence of these Kunitz peptides. The overall interpretation of our analyses discloses a rapidly emerging Kunitz group with a distinct disulfide bond pattern from the I. ricinus salivary gland transcriptome. CONCLUSIONS: We propose a model to explain the structural and functional evolution of tick salivary Kunitz peptides that we call target-oriented evolution. Our study reveals that combining analytical approaches (transcriptomes, computational, bioinformatics and phylogenetics) improves our understanding of the biological functions of important salivary gland mediators during tick feeding.


Assuntos
Proteínas de Artrópodes/genética , Evolução Molecular , Ixodes/genética , Proteínas e Peptídeos Salivares/genética , Transcriptoma , Sequência de Aminoácidos , Animais , Proteínas de Artrópodes/química , Proteínas de Artrópodes/metabolismo , Biologia Computacional , Feminino , Ixodes/química , Ixodes/classificação , Ixodes/metabolismo , Filogenia , Estrutura Terciária de Proteína , Proteínas e Peptídeos Salivares/química , Proteínas e Peptídeos Salivares/metabolismo , Alinhamento de Sequência
15.
FASEB J ; 27(12): 4745-56, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23964076

RESUMO

Tick salivary gland (SG) proteins possess powerful pharmacologic properties that facilitate tick feeding and pathogen transmission. For the first time, SG transcriptomes of Ixodes ricinus, an important disease vector for humans and animals, were analyzed using next-generation sequencing. SGs were collected from different tick life stages fed on various animal species, including cofeeding of nymphs and adults on the same host. Four cDNA samples were sequenced, discriminating tick SG transcriptomes of early- and late-feeding nymphs or adults. In total, 441,381,454 pyrosequencing reads and 67,703,183 Illumina reads were assembled into 272,220 contigs, of which 34,560 extensively annotated coding sequences are disclosed; 8686 coding sequences were submitted to GenBank. Overall, 13% of contigs were classified as secreted proteins that showed significant differences in the transcript representation among the 4 SG samples, including high numbers of sample-specific transcripts. Detailed phylogenetic reconstructions of two relatively abundant SG-secreted protein families demonstrated how this study improves our understanding of the molecular evolution of hematophagy in arthropods. Our data significantly increase the available genomic information for I. ricinus and form a solid basis for future tick genome/transcriptome assemblies and the functional analysis of effectors that mediate the feeding physiology and parasite-vector interaction of I. ricinus.


Assuntos
Ixodes/química , Glândulas Salivares/metabolismo , Transcriptoma , Animais , Proteínas de Artrópodes/química , Proteínas de Artrópodes/genética , Sequência de Bases , DNA Complementar/química , DNA Complementar/genética , Evolução Molecular , Sequenciamento de Nucleotídeos em Larga Escala , Ixodes/genética , Ixodes/metabolismo , Dados de Sequência Molecular , Filogenia , Estrutura Terciária de Proteína , Análise de Sequência de DNA
16.
PLoS One ; 8(5): e62562, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23658744

RESUMO

BACKGROUND: A salivary proteome-transcriptome project on the hard tick Ixodes scapularis revealed that Kunitz peptides are the most abundant salivary proteins. Ticks use Kunitz peptides (among other salivary proteins) to combat host defense mechanisms and to obtain a blood meal. Most of these Kunitz peptides, however, remain functionally uncharacterized, thus limiting our knowledge about their biochemical interactions. RESULTS: We discovered an unusual cysteine motif in a Kunitz peptide. This peptide inhibits several serine proteases with high affinity and was named tryptogalinin due to its high affinity for ß-tryptase. Compared with other functionally described peptides from the Acari subclass, we showed that tryptogalinin is phylogenetically related to a Kunitz peptide from Rhipicephalus appendiculatus, also reported to have a high affinity for ß-tryptase. Using homology-based modeling (and other protein prediction programs) we were able to model and explain the multifaceted function of tryptogalinin. The N-terminus of the modeled tryptogalinin is detached from the rest of the peptide and exhibits intrinsic disorder allowing an increased flexibility for its high affinity with its inhibiting partners (i.e., serine proteases). CONCLUSIONS: By incorporating experimental and computational methods our data not only describes the function of a Kunitz peptide from Ixodes scapularis, but also allows us to hypothesize about the molecular basis of this function at the atomic level.


Assuntos
Proteínas de Artrópodes/química , Ixodes/metabolismo , Proteínas e Peptídeos Salivares/química , Inibidores de Serina Proteinase/química , Triptases/química , Motivos de Aminoácidos , Animais , Proteínas de Artrópodes/classificação , Proteínas de Artrópodes/genética , Proteínas de Artrópodes/metabolismo , Cisteína/química , Cisteína/genética , Humanos , Ixodes/química , Ixodes/genética , Modelos Moleculares , Dados de Sequência Molecular , Filogenia , Estrutura Terciária de Proteína , Proteínas Recombinantes/química , Proteínas Recombinantes/classificação , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Rhipicephalus/química , Rhipicephalus/genética , Rhipicephalus/metabolismo , Proteínas e Peptídeos Salivares/classificação , Proteínas e Peptídeos Salivares/genética , Proteínas e Peptídeos Salivares/metabolismo , Homologia de Sequência de Aminoácidos , Inibidores de Serina Proteinase/classificação , Inibidores de Serina Proteinase/genética , Inibidores de Serina Proteinase/metabolismo , Triptases/antagonistas & inibidores , Triptases/metabolismo
17.
Pathol Res Pract ; 209(6): 380-7, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23706943

RESUMO

Previous studies suggest different pathways in the molecular development of hepatocellular carcinoma (HCC). We investigated the pattern of chromosomal imbalances in HCC depending on the type of underlying liver disease as detected by comparative genomic hybridization in 67 cases of primary HCC occurring in non-cirrhotic livers (n=30), in liver cirrhosis (LC) related to alcohol intake (n=9), cryptogenic or metabolic changes (n=11), and chronic viral hepatitis B or C (n=17). HCC were treated by liver resection in 48 patients and transplantation in 19 patients. The 10-year disease-free and overall survival rates were 51% and 68%, respectively. The copy number changes occurring in more than 10% of cases were gains at 8q (55%), 1q (49%), 7q (15%), 7p (13%), 6p (12%), and 20q (12%), as well as losses at 8p (55%), 4q (33%), 6q (33%), 13q (25%), 14q (24%), 17p (22%), 16q (19%), 1p (18%), 18q (16%), 9p (13%), 10q (13%), 4p (12%), and 9q (12%). HCC arising in alcoholic LC showed a different pattern with significantly fewer net changes (p=0.008), particularly fewer chromosomal gains (p=0.008) and fewer breakpoints (p=0.003) compared to the other investigated HCC subgroups. Future clinical studies should evaluate the prognostic relevance of these findings.


Assuntos
Carcinoma Hepatocelular/genética , Aberrações Cromossômicas , Hibridização Genômica Comparativa , Hepatite B Crônica/genética , Hepatite C Crônica/genética , Cirrose Hepática/genética , Neoplasias Hepáticas/genética , Adulto , Idoso , Carcinoma Hepatocelular/mortalidade , Carcinoma Hepatocelular/patologia , Carcinoma Hepatocelular/cirurgia , Carcinoma Hepatocelular/virologia , Intervalo Livre de Doença , Europa (Continente)/epidemiologia , Feminino , Hepatite B Crônica/complicações , Hepatite B Crônica/mortalidade , Hepatite C Crônica/complicações , Hepatite C Crônica/mortalidade , Humanos , Estimativa de Kaplan-Meier , Cirrose Hepática/mortalidade , Cirrose Hepática/virologia , Cirrose Hepática Alcoólica/genética , Neoplasias Hepáticas/mortalidade , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/cirurgia , Neoplasias Hepáticas/virologia , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento
18.
J Biol Chem ; 288(20): 14341-14361, 2013 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-23564450

RESUMO

The function of the antigen-5/CAP family of proteins found in the salivary gland of bloodsucking animals has remained elusive for decades. Antigen-5 members from the hematophagous insects Dipetalogaster maxima (DMAV) and Triatoma infestans (TIAV) were expressed and discovered to attenuate platelet aggregation, ATP secretion, and thromboxane A2 generation by low doses of collagen (<1 µg/ml) but no other agonists. DMAV did not interact with collagen, glycoprotein VI, or integrin α2ß1. This inhibitory profile resembles the effects of antioxidants Cu,Zn-superoxide dismutase (Cu,Zn-SOD) in platelet function. Accordingly, DMAV was found to inhibit cytochrome c reduction by O2[Symbol: see text] generated by the xanthine/xanthine oxidase, implying that it exhibits antioxidant activity. Moreover, our results demonstrate that DMAV blunts the luminescence signal of O2[Symbol: see text] generated by phorbol 12-myristate 13-acetate-stimulated neutrophils. Mechanistically, inductively coupled plasma mass spectrometry and fluorescence spectroscopy revealed that DMAV, like Cu,Zn-SOD, interacts with Cu(2+), which provides redox potential for catalytic removal of O2[Symbol: see text]. Notably, surface plasmon resonance experiments (BIAcore) determined that DMAV binds sulfated glycosaminoglycans (e.g. heparin, KD ~100 nmol/liter), as reported for extracellular SOD. Finally, fractions of the salivary gland of D. maxima with native DMAV contain Cu(2+) and display metal-dependent antioxidant properties. Antigen-5/CAP emerges as novel family of Cu(2+)-dependent antioxidant enzymes that inhibit neutrophil oxidative burst and negatively modulate platelet aggregation by a unique salivary mechanism.


Assuntos
Cobre/metabolismo , Sequestradores de Radicais Livres/metabolismo , Neutrófilos/metabolismo , Agregação Plaquetária , Explosão Respiratória , Triatoma/enzimologia , Sequência de Aminoácidos , Animais , Antioxidantes/metabolismo , Bovinos , Colágeno/metabolismo , Glicosaminoglicanos/metabolismo , Cavalos , Humanos , Peróxido de Hidrogênio/análise , Dados de Sequência Molecular , Oxigênio/metabolismo , Filogenia , Adesividade Plaquetária , Glândulas Salivares/enzimologia , Alinhamento de Sequência , Tubarões , Enxofre/química , Ressonância de Plasmônio de Superfície , Suínos
19.
Parasit Vectors ; 5: 268, 2012 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-23171708

RESUMO

BACKGROUND: During the last decades, population densities of Ixodes ricinus and prevalences of Borrelia burgdorferi s.l. have increased in different regions in Europe. In the present study, we determined tick abundance and the prevalence of different Borrelia genospecies in ticks from three sites in the Siebengebirge, Germany, which were already examined in the years 1987, 1989, 2001 and 2003. Data from all investigations were compared. METHODS: In 2007 and 2008, host-seeking I. ricinus were collected by monthly blanket dragging at three distinct vegetation sites in the Siebengebirge, a nature reserve and a well visited local recreation area near Bonn, Germany. In both years, 702 ticks were tested for B. burgdorferi s.l. DNA by nested PCR, and 249 tick samples positive for Borrelia were further genotyped by reverse line blotting. RESULTS: A total of 1046 and 1591 I. ricinus were collected in 2007 and 2008, respectively. In comparison to previous studies at these sites, the densities at all sites increased from 1987/89 and/or from 2003 until 2008. Tick densities and Borrelia prevalences in 2007 and 2008, respectively, were not correlated for all sites and both years. Overall, Borrelia prevalence of all ticks decreased significantly from 2007 (19.5%) to 2008 (16.5%), thus reaching the same level as in 2001 two times higher than in 1987/89 (7.6%). Since 2001, single infections with a Borrelia genospecies predominated in all collections, but the number of multiple infections increased, and in 2007, for the first time, triple Borrelia infections occurred. Prevalences of Borrelia genospecies differed considerably between the three sites, but B. garinii or B. afzelii were always the most dominant genospecies. B. lusitaniae was detected for the first time in the Siebengebirge, also in co-infections with B. garinii or B. valaisiana. CONCLUSIONS: Over the last two centuries tick densities have changed in the Siebengebirge at sites that remained unchanged by human activity since they belong to a nature reserve. Abiotic and biotic conditions most likely favored the host-seeking activity of I. ricinus and the increase of multiple Borrelia infections in ticks. These changes have led to a potential higher risk of humans and animals to be infected with Lyme borreliosis.


Assuntos
Grupo Borrelia Burgdorferi/isolamento & purificação , Ixodes/crescimento & desenvolvimento , Ixodes/microbiologia , Animais , Grupo Borrelia Burgdorferi/classificação , Grupo Borrelia Burgdorferi/genética , DNA Bacteriano/genética , Alemanha , Reação em Cadeia da Polimerase , Densidade Demográfica , Prevalência , Fatores de Tempo
20.
Ticks Tick Borne Dis ; 3(3): 117-27, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22647711

RESUMO

Ticks, as obligate hematophagous ectoparasites, impact greatly on animal and human health because they transmit various pathogens worldwide. Over the last decade, several cystatins from different hard and soft ticks were identified and biochemically analyzed for their role in the physiology and blood feeding lifestyle of ticks. All these cystatins are potent inhibitors of papain-like cysteine proteases, but not of legumain. Tick cystatins were either detected in the salivary glands and/or the midgut, key tick organs responsible for blood digestion and the expression of pharmacologically potent salivary proteins for blood feeding. For example, the transcription of two cystatins named HlSC-1 and Sialostatin L2 was highly upregulated in these tick tissues during feeding. Vaccinating hosts against Sialostatin L2 and Om-cystatin 2 as well as silencing of a cystatin gene from Amblyomma americanum significantly inhibited the feeding ability of ticks. Additionally, Om-cystatin 2 and Sialostatin L possessed strong host immunosuppressive properties by inhibiting dendritic cell maturation due to their interaction with cathepsin S. These two cystatins, together with Sialostatin L2 are the first tick cystatins with resolved three-dimensional structure. Sialostatin L, furthermore, showed preventive properties against autoimmune diseases. In the case of the cystatin Hlcyst-2, experimental evidence showed its role in tick innate immunity, since increased Hlcyst-2 transcript levels were detected in Babesia gibsoni-infected larval ticks and the protein inhibited Babesia growth. Other cystatins, such as Hlcyst-1 or Om-cystatin 2 are assumed to be involved in regulating blood digestion. Only for Bmcystatin was a role in tick embryogenesis suggested. Finally, all the biochemically analyzed tick cystatins are powerful protease inhibitors, and some may be novel antigens for developing anti-tick vaccines and drugs of medical importance due to their stringent target specificity.


Assuntos
Cistatinas/farmacologia , Inibidores de Cisteína Proteinase/farmacologia , Comportamento Alimentar/efeitos dos fármacos , Carrapatos/efeitos dos fármacos , Sequência de Aminoácidos , Animais , Humanos , Modelos Moleculares , Dados de Sequência Molecular , Alinhamento de Sequência , Carrapatos/fisiologia
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