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1.
Nutrients ; 14(3)2022 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-35276779

RESUMO

Ionic calcium can help in the prevention of the process of osseous decalcification. This study aimed to evaluate the physicochemical properties and toxic effects of ionic calcium-fiber supplement (ICa+) and its impact on bone health preservation in mice C57/BL6 fed a calcium-deficient diet. Physicochemical properties include FTIR, apparent calcium solubility estimated by the calcium ratio obtained by ionization chromatography and atomic absorption. In vitro genotoxicity and cytotoxicity of the ICa+ were assessed. Twenty-five 7-week-old C57/BL6 mice were fed calcium-free diet (CFD) or CFD plus CaCO3 (1.33 mg Ca) or CFD plus ICa+ (1.33-6.66 mg Ca) for six weeks. After that, bone mass and microstructure parameters were assessed. Histological staining was performed to determine calcium deposits. ICa+ (100%) exhibited an apparent calcium solubility higher than CaCO3 (12.3%). ICa+ showed no cytotoxic and genotoxic in vitro activities. Histomorphometry analysis showed that the ICa+ treated group displayed a higher trabecular number than the trabecular space. Also, the ratio BV/TV was increased compared with all treatments. Ionic calcium-fiber supplementation prevents bone deterioration compared to mice fed a calcium-deficient diet.


Assuntos
Distúrbios do Metabolismo do Cálcio , Cálcio da Dieta , Animais , Densidade Óssea , Cálcio , Cálcio da Dieta/farmacologia , Suplementos Nutricionais , Camundongos
2.
Pharmaceutics ; 13(10)2021 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-34684012

RESUMO

Metal-based nanoparticles are widely used to deliver bioactive molecules and drugs to improve cancer therapy. Several research works have highlighted the synthesis of gold and silver nanoparticles by green chemistry, using biological entities to minimize the use of solvents and control their physicochemical and biological properties. Recent advances in evaluating the anticancer effect of green biogenic Au and Ag nanoparticles are mainly focused on the use of conventional 2D cell culture and in vivo murine models that allow determination of the half-maximal inhibitory concentration, a critical parameter to move forward clinical trials. However, the interaction between nanoparticles and the tumor microenvironment is not yet fully understood. Therefore, it is necessary to develop more human-like evaluation models or to improve the existing ones for a better understanding of the molecular bases of cancer. This review provides recent advances in biosynthesized Au and Ag nanoparticles for seven of the most common and relevant cancers and their biological assessment. In addition, it provides a general idea of the in silico, in vitro, ex vivo, and in vivo models used for the anticancer evaluation of green biogenic metal-based nanoparticles.

3.
Parasite ; 28: 65, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34533454

RESUMO

Rhipicephalus (Boophilus) microplus ticks are obligatory hematophagous ectoparasites of cattle and act as vectors for disease-causing microorganisms. Conventional tick control is based on the application of chemical acaricides; however, their uncontrolled use has increased resistant tick populations, as well as food and environmental contamination. Alternative immunological tick control has shown to be partially effective. Therefore, there is a need to characterize novel antigens in order to improve immunological protection. The aim of this work was to evaluate Cys-loop receptors as vaccine candidates. N-terminal domains of a glutamate receptor and of a glycine-like receptor were recombinantly produced in Escherichia coli. Groups of BALB/c mice were independently immunized with four doses of each recombinant protein emulsified with Freund's adjuvant. Both vaccine candidates were immunogenic in mice as demonstrated by western blot analysis. Next, recombinant proteins were independently formulated with the adjuvant Montanide ISA 50 V2 and evaluated in cattle infested with Rhipicephalus microplus tick larvae. Groups of three European crossbred calves were immunized with three doses of each adjuvanted protein. ELISA test was used to evaluate the IgG immune response elicited against the recombinant proteins. Results showed that vaccine candidates generated a moderate humoral response on vaccinated cattle. Vaccination significantly affected the number of engorged adult female ticks, having no significant effects on tick weight, egg weight and egg fertility values. Vaccine efficacies of 33% and 25% were calculated for the glutamate receptor and the glycine-like receptor, respectively.


TITLE: Évaluation de l'immunoprotection du domaine N-terminal recombinant des récepteurs Cys-loop contre l'infestation par les tiques Rhipicephalus (Boophilus) microplus. ABSTRACT: Les tiques Rhipicephalus (Boophilus) microplus sont des ectoparasites hématophages obligatoires des bovins et agissent comme vecteurs de micro-organismes pathogènes. Le contrôle conventionnel des tiques est basé sur l'application d'acaricides chimiques, mais leur utilisation incontrôlée a augmenté les populations de tiques résistantes ainsi que la contamination des aliments et de l'environnement. Le contrôle immunologique alternatif des tiques s'est avéré partiellement efficace. Par conséquent, il est nécessaire de caractériser de nouveaux antigènes afin d'améliorer la protection immunologique. Le but de ce travail était d'évaluer les récepteurs Cys-loop comme candidats vaccins. Les domaines N-terminaux d'un récepteur du glutamate et d'un récepteur de type glycine ont été produits par recombinaison chez Escherichia coli. Des groupes de souris BALB/c ont été immunisés indépendamment avec quatre doses de chaque protéine recombinante émulsionnée avec l'adjuvant de Freund. Les deux vaccins candidats étaient immunogènes chez la souris, comme l'a démontré l'analyse par transfert Western. Ensuite, des protéines recombinantes ont été formulées indépendamment avec l'adjuvant Montanide ISA 50 V2 et évaluées chez des bovins infestés de larves de tiques Rhipicephalus microplus. Des groupes de trois veaux croisés européens ont été immunisés avec trois doses de chaque protéine avec adjuvant. Le test ELISA a été utilisé pour évaluer la réponse immunitaire IgG induite contre les protéines recombinantes. Les résultats ont montré que les candidats vaccins généraient une réponse humorale modérée sur les bovins vaccinés. La vaccination a affecté de manière significative le nombre de tiques femelles adultes engorgées mais n'a eu aucun effet significatif sur le poids des tiques, le poids des œufs et les valeurs de fertilité des œufs. Des efficacités vaccinales de 33 % et 25 % ont été calculées pour le récepteur du glutamate et le récepteur de type glycine, respectivement.


Assuntos
Doenças dos Bovinos , Receptores de Canais Iônicos de Abertura Ativada por Ligante com Alça de Cisteína , Rhipicephalus , Infestações por Carrapato , Animais , Bovinos , Doenças dos Bovinos/prevenção & controle , Feminino , Camundongos , Camundongos Endogâmicos BALB C , Infestações por Carrapato/prevenção & controle , Infestações por Carrapato/veterinária
4.
Biosensors (Basel) ; 10(10)2020 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-33096879

RESUMO

Background: Several studies have shown that patients with cancer have antibodies in serum that react with cellular autoantigens, known as Tumor-Associated Antigens (TAA). The present work aimed to determine whether a mini-array comprising four recombinant TAA increases the detection of specific serum antibodies for the diagnosis of early-stage breast cancer. Methods: The mini-array included Alpha 1-AntiTrypsin (A1AT), TriosePhosphate Isomerase 1 (TPI1), Peptidyl-Prolyl cis-trans Isomerase A (PPIA), and PeroxiReDoXin 2 (PRDX2) full-length recombinant proteins. The proteins were produced after gene cloning, expression, and purification, and were verified by Western blot assays. Then, Dot-Blot was performed to find antibodies against the four TAA in 12 sera from women with early-stage breast cancer (stage II) and 12 sera from healthy women. Results: Antibody detection against individual TAA in early-stage breast cancer sera ranged from 58.3% to 83.3%. However, evaluation of the four TAA showed that there was a positive antibody reaction reaching a sensitivity of 100% and a specificity of 85% in early-stage breast cancer, suggesting that this mini-array must be evaluated as a clinical diagnostic tool for early-stage breast cancer in a larger sample size. Conclusion: Our results suggest that TAA mini-arrays may provide a promising and powerful method for improving the detection of breast cancer in Mexican women.


Assuntos
Biomarcadores Tumorais/análise , Técnicas Biossensoriais , Neoplasias da Mama/diagnóstico , Soro/química , Adulto , Antígenos de Neoplasias , Neoplasias da Mama/sangue , Feminino , Testes Hematológicos , Humanos , Pessoa de Meia-Idade
5.
Animals (Basel) ; 9(9)2019 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-31480266

RESUMO

Bovine tuberculosis (bTB) is a disease of cattle that represents a risk to public health and causes severe economic losses to the livestock industry. Recently, genetic studies, like genome-wide association studies (GWAS) have greatly improved the investigation of complex diseases identifying thousands of disease-associated genomic variants. Here, we present evidence of genetic variants associated with resistance to TB in Mexican dairy cattle using a case-control approach with a selective DNA pooling experimental design. A total of 154 QTLRs (quantitative trait loci regions) at 10% PFP (proportion of false positives), 42 at 5% PFP and 5 at 1% PFP have been identified, which harbored 172 annotated genes. On BTA13, five new QTLRs were identified in the MACROD2 and KIF16B genes, supporting their involvement in resistance to bTB. Six QTLRs harbor seven annotated genes that have been previously reported as involved in immune response against Mycobacterium spp: BTA (Bos taurus autosome) 1 (CD80), BTA3 (CTSS), BTA 3 (FCGR1A), BTA 23 (HFE), BTA 25 (IL21R), and BTA 29 (ANO9 and SIGIRR). We identified novel QTLRs harboring genes involved in Mycobacterium spp. immune response. This is a first screening for resistance to TB infection on Mexican dairy cattle based on a dense SNP (Single Nucleotide Polymorphism) chip.

6.
Microb Pathog ; 103: 57-64, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28007592

RESUMO

Bovine colostrum contains compounds, which provide passive immune protection from mother to newborn calves. Little is known about cytokine levels and their role in bovine colostrum. Moreover, the capacity of bovine colostrum cells to mount specific immune responses after natural exposure to bovine tuberculosis (bTB) antigens in dairy herds has not been studied, thus far. The purpose of this study was to identify biomarkers for bTB infection measurable in bovine colostrum. The present study reveals that isolated-immune colostrum cells can mount a specific immune response against bTB antigens, by measuring the novo IFN-γ release in cell culture. We found that IFN-γ levels in the responders (Bov+) to bTB antigen were higher than in non-responders (Bov-). On the other hand, proinflammatory cytokines contained in colostrum's whey were tested in Tuberculin Skin Test (TST) reactor (TST+) and non-reactor (TST-) animals to assess their potential role as biomarker. We observed that IFN-γ levels were lower or undetectable, as opposed to IL4 levels were measurable, the TNF-α level was higher in TST- than TST+, while IL-6 levels showed the opposite reaction and with no statistical significance. Moreover, IL-1α mRNA expression levels were higher in colostrum mononuclear cells (CMC) in Bov+ cattle. Collectively, these data suggest that the differential expression of pro and anti-inflammatory cytokines could have relevant value to diagnose bTB in cattle.


Assuntos
Biomarcadores , Colostro/metabolismo , Citocinas/metabolismo , Mediadores da Inflamação/metabolismo , Mycobacterium bovis/imunologia , Tuberculose Bovina/imunologia , Tuberculose Bovina/metabolismo , Animais , Antígenos de Bactérias/imunologia , Bovinos , Citocinas/genética , Feminino , Expressão Gênica , Testes de Liberação de Interferon-gama , Tuberculose Bovina/genética
7.
Virol J ; 13(1): 196, 2016 11 29.
Artigo em Inglês | MEDLINE | ID: mdl-27894314

RESUMO

BACKGROUND: Assembly of recombinant capsid proteins into virus-like particles (VLPs) still represents an interesting challenge in virus-based nanotechnologies. The structure of VLPs has gained importance for the development and design of new adjuvants and antigen carriers. The potential of Tobacco etch virus capsid protein (TEV CP) as adjuvant has not been evaluated to date. FINDINGS: Two constructs for TEV CP expression in Escherichia coli were generated: a wild-type version (TEV-CP) and a C-terminal hexahistidine (His)-tagged version (His-TEV-CP). Although both versions were expressed in the soluble fraction of E. coli lysates, only His-TEV-CP self-assembled into micrometric flexuous filamentous VLPs. In addition, the His-tag enabled high yields and facilitated purification of TEV VLPs. These TEV VLPs elicited broader IgG2-specific antibody response against a novel porcine reproductive and respiratory syndrome virus (PRRSV) protein when compared to the potent IgG1 response induced by the protein alone. CONCLUSIONS: His-TEV CP was purified by immobilized metal affinity chromatography and assembled into VLPs, some of them reaching 2-µm length. TEV VLPs administered along with PRRSV chimeric protein changed the IgG2/IgG1 ratio against the chimeric protein, suggesting that TEV CP can modulate the immune response against a soluble antigen.


Assuntos
Adjuvantes Imunológicos/administração & dosagem , Anticorpos Antivirais/sangue , Proteínas do Capsídeo/administração & dosagem , Vírus da Síndrome Respiratória e Reprodutiva Suína/imunologia , Potyvirus/imunologia , Vacinas Virais/imunologia , Virossomos/administração & dosagem , Citoesqueleto de Actina/metabolismo , Adjuvantes Imunológicos/metabolismo , Proteínas do Capsídeo/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo , Expressão Gênica , Imunoglobulina G/sangue , Multimerização Proteica , Proteínas Recombinantes/genética , Proteínas Recombinantes/imunologia , Proteínas Recombinantes/metabolismo , Virossomos/metabolismo
8.
Exp Parasitol ; 170: 227-235, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27729251

RESUMO

Rhipicephalus (Boophilus) microplus ticks are obligatory hematophagous ectoparasites of cattle and act as vectors for disease-causing microorganisms. Conventional tick control is based on the use of chemical acaricides; however, their uncontrolled use has increased tSresistant tick populations, as well as food and environmental contamination. Alternative immunological tick control has shown to be partially effective. The only anti-tick vaccine commercially available at present in the world is based on intestinal Bm86 protein, and shows a variable effectiveness depending on tick strains or geographic isolates. Therefore, there is a need to characterize new antigens in order to improve immunological protection. The aim of this work was to identify immunogenic proteins from ovarian tissue extracts of R. microplus, after cattle immunization. Results showed that ovarian proteins complexed with the adjuvant Montanide ISA 50 V generated a strong humoral response on vaccinated cattle. IgG levels peaked at fourth post-immunization week and remained high until the end of the experiment. 1D and 2D SDS-PAGE-Western blot assays with sera from immunized cattle recognized several ovarian proteins. Reactive bands were cut and analyzed by LC-MS/MS. They were identified as Vitellogenin, Vitellogenin-2 precursor and Yolk Cathepsin. Our findings along with bioinformatic analysis indicate that R. microplus has several Vitellogenin members, which are proteolytically processed to generate multiple polypeptide fragments. This apparent complexity of vitellogenic tick molecular targets gives the opportunity to explore their potential usefulness as vaccine candidates but, at the same time, imposes a challenge on the selection of the appropriate set of antigens.


Assuntos
Vetores Aracnídeos/imunologia , Proteínas de Artrópodes/imunologia , Rhipicephalus/imunologia , Controle de Ácaros e Carrapatos/métodos , Animais , Western Blotting , Bovinos , Doenças dos Bovinos/prevenção & controle , DNA Complementar/biossíntese , Eletroforese/métodos , Desenvolvimento Embrionário/imunologia , Ensaio de Imunoadsorção Enzimática , Feminino , Imunoglobulina G/sangue , Larva/imunologia , Oogênese/imunologia , Ovário/imunologia , Reação em Cadeia da Polimerase , Proteômica/métodos , RNA/genética , RNA/isolamento & purificação , Reprodução/imunologia , Espectrometria de Massas em Tandem , Infestações por Carrapato/prevenção & controle , Infestações por Carrapato/veterinária , Vacinas , Vitelogeninas/biossíntese , Vitelogeninas/imunologia
9.
Mol Biotechnol ; 56(12): 1110-20, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25119647

RESUMO

There is a growing interest in using virus-like particles (VLPs) as scaffolds for the presentation of antigens of choice to the immune system. In this work, VLPs from papaya ringspot virus capsid protein expressed in Escherichia coli were evaluated as enhancers of antibody response against a soluble antigen. Interestingly, although the capsid protein lacks a histidine tag, its purification by immobilized metal affinity chromatography was achieved. The formation of VLPs was demonstrated by electron microscopy for the first time for this capsid protein. VLPs were enriched by polyethylene glycol precipitation. Additionally, these VLPs were chemically coupled to green fluorescent protein in order to evaluate them as antigen carriers; however, bioconjugate instability was observed. Nonetheless, the adjuvant effect of these VLPs on BALB/c mice was evaluated, using GFP as antigen, resulting in a significant increase in anti-GFP IgG response, particularly, IgG1 class, demonstrating that the VLPs enhance the immune response against the antigen chosen in this study.


Assuntos
Proteínas do Capsídeo/imunologia , Proteínas do Capsídeo/isolamento & purificação , Potyvirus/metabolismo , Vacinas de Partículas Semelhantes a Vírus/imunologia , Animais , Anticorpos Antivirais/imunologia , Proteínas do Capsídeo/biossíntese , Proteínas do Capsídeo/química , Cromatografia de Afinidade , Escherichia coli/genética , Escherichia coli/metabolismo , Feminino , Proteínas de Fluorescência Verde/imunologia , Proteínas de Fluorescência Verde/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Potyvirus/imunologia , Vacinas de Partículas Semelhantes a Vírus/química
10.
Clin Vaccine Immunol ; 20(4): 627-33, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23425597

RESUMO

Bovine tuberculosis (bTB) remains a problem on many dairy farms in Mexico, as well as a public health risk. We previously found a high frequency of Mycobacterium bovis DNA in colostrum from dairy cows using a nested PCR to detect mpb70. Since there are no reliable in vivo tests to determine the effectiveness of booster Mycobacterium bovis BCG vaccination against bTB, in this work we monitored M. bovis DNA in colostrum by using this nested PCR. In order to decrease the risk of adverse reactions in animals likely containing viable M. bovis, a single application of BCG and a subunit vaccine (EEP-1) formulated with M. bovis culture filtrate proteins (CFP) and a copolymer as the adjuvant was performed in tuberculin skin test-negative cattle (TST(-)), while TST reactor animals (TST(+)) received EEP-1 only. Booster immunization using EEP-1 was applied to both groups, 2 months after primary vaccination to whole herds and 12 months later to lactating cows. Colostrum samples were collected from 6 farms where the cows were vaccinated over a 12-month period postvaccination and, for comparison, from one control farm where the cows were not vaccinated with comparable bTB prevalence. We observed an inverse relationship between the frequency of M. bovis DNA detection and time postvaccination at the first (P < 0.001) and second (P < 0.0001) 6-month periods. Additionally, the concentration of gamma interferon (IFN-γ) was higher in mpb70 PCR-positive colostrum samples (P = 0.0003). These results suggest that M. bovis DNA frequency in colostrum could be a potentially useful biomarker for bTB vaccine efficacy on commercial dairy farms.


Assuntos
Vacina BCG/imunologia , Colostro/microbiologia , DNA Bacteriano/isolamento & purificação , Mycobacterium bovis/isolamento & purificação , Tuberculose Bovina/prevenção & controle , Animais , Vacina BCG/administração & dosagem , Bovinos , México , Mycobacterium bovis/genética , Mycobacterium bovis/imunologia , Reação em Cadeia da Polimerase , Tuberculose Bovina/imunologia , Tuberculose Bovina/microbiologia , Vacinas de Subunidades Antigênicas/administração & dosagem , Vacinas de Subunidades Antigênicas/imunologia
11.
Rev. psiquiatr. infanto-juv ; 30(3): 40-43, 2013. tab, graf
Artigo em Espanhol | IBECS | ID: ibc-186123

RESUMO

La fobia a la alimentación, fobia a tragar o fobia a atragantarse es una patología frecuente en la clínica pero poco estudiada desde el punto de vista científico. Si bien este trastorno no se encuentra recogido en ninguna de las clasificaciones diagnósticas actuales, el interés despertado desde el ámbito clínico ha hecho proliferar numerosos estudios de casos. El objetivo de esta publicación es la presentación de un caso clínico, así como la intervención llevada a cabo desde el servicio de Salud Mental Infanto Juvenil en coordinación con Atención Primaria y Atención Temprana. Se trata de un varón de 30 meses de edad que presentaba rechazo a la ingesta de alimentos sólidos tras intervención con gastrostomía por reflujo gastroesofágico. Desde Salud Mental se puso en marcha un programa de modificación de conducta para la progresiva incorporación de alimentación vía oral y la retirada de alimentación vía parenteral. Se consiguió la total restitución de la alimentación oral a los seis meses de intervención


Feeding phobia; swallow phobia or chocking phobia are frequent pathologies in clinical practice but barely studied in a scientific way. Although this disease is not under any of the clinical classifications, it has drawn the clinicians' attention and it has generated a considerable body of research through clinical case studies. The purpose of this paper is the presentation of a clinical case and the intervention carried out from Childhood Mental Health Services in coordination with Primary Attention Services and Early Childhood Intervention Services. It is about a 30-months-old child who presented refusal behaviour to ingest solid food after an intervention with gastrostomy for gastroesophageal reflux. From Mental Health Services, a behavioural modification program was carried out, with de purpose of a progressive incorporation of oral feeding and the withdrawal of parental nutrition. It was achieved a complete restitution of oral feeding after six months of treatment


Assuntos
Humanos , Masculino , Pré-Escolar , Transtornos de Alimentação na Infância/psicologia , Terapia Familiar/métodos , Transtornos Fóbicos/psicologia , Controle Comportamental/métodos , Gastrostomia/psicologia , Nutrição Parenteral Total/psicologia , Refluxo Gastroesofágico/psicologia , Transtornos de Deficit da Atenção e do Comportamento Disruptivo/psicologia
12.
Cell Res ; 21(11): 1564-77, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21606955

RESUMO

Gene expression can be regulated by chromatin modifiers, transcription factors and proteins that modulate DNA architecture. Among the latter, AT-hook transcription factors have emerged as multifaceted regulators that can activate or repress broad A/T-rich gene networks. Thus, alterations of AT-hook genes could affect the transcription of multiple genes causing global cell dysfunction. Here we report that targeted deletions of mouse AKNA, a hypothetical AT-hook-like transcription factor, sensitize mice to pathogen-induced inflammation and cause sudden neonatal death. Compared with wild-type littermates, AKNA KO mice appeared weak, failed to thrive and most died by postnatal day 10. Systemic inflammation, predominantly in the lungs, was accompanied by enhanced leukocyte infiltration and alveolar destruction. Cytologic, immunohistochemical and molecular analyses revealed CD11b(+)Gr1(+) neutrophils as major tissue infiltrators, neutrophilic granule protein, cathelin-related antimicrobial peptide and S100A8/9 as neutrophil-specific chemoattracting factors, interleukin-1ß and interferon-γ as proinflammatory mediators, and matrix metalloprotease 9 as a plausible proteolytic trigger of alveolar damage. AKNA KO bone marrow transplants in wild-type recipients reproduced the severe pathogen-induced reactions and confirmed the involvement of neutrophils in acute inflammation. Moreover, promoter/reporter experiments showed that AKNA could act as a gene repressor. Our results support the concept of coordinated pathway-specific gene regulation functions modulating the intensity of inflammatory responses, reveal neutrophils as prominent mediators of acute inflammation and suggest mechanisms underlying the triggering of acute and potentially fatal immune reactions.


Assuntos
Proteínas de Ligação a DNA/deficiência , Proteínas de Ligação a DNA/genética , Redes Reguladoras de Genes , Proteínas Nucleares/deficiência , Proteínas Nucleares/genética , Alvéolos Pulmonares/patologia , Fatores de Transcrição/deficiência , Fatores de Transcrição/genética , Animais , Peptídeos Catiônicos Antimicrobianos , Calgranulina A/genética , Calgranulina A/metabolismo , Calgranulina B/genética , Calgranulina B/metabolismo , Catelicidinas/genética , Catelicidinas/metabolismo , Proteínas de Ligação a DNA/metabolismo , Éxons , Inflamação/genética , Inflamação/imunologia , Interferon gama/genética , Interferon gama/metabolismo , Interleucina-1beta/genética , Interleucina-1beta/metabolismo , Pulmão/patologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Neutrófilos/imunologia , Neutrófilos/fisiologia , Proteínas Nucleares/metabolismo , Fenótipo , Fatores de Transcrição/metabolismo
13.
Biochem Biophys Res Commun ; 342(4): 1014-21, 2006 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-16513090

RESUMO

Reversible protein tyrosine phosphorylation is an essential signal transduction mechanism that regulates cell growth, differentiation, mobility, metabolism, and survival. Two genes coding for protein tyrosine phophatases, designed EhPTPA and EhPTPB, were cloned from Entamoeba histolytica. EhPTPA and EhPTPB proteins showed amino acid sequence identity of 37%, both EhPTPases showed similarity with Dictyostelium discoideum and vertebrate trasmembranal PTPases. mRNA levels of EhPTPA gene are up-regulated in trophozoites recovered after 96h of liver abscess development in the hamster model. EhPTPA protein expressed as a glutathione S-transferase fusion protein (GST::EhPTPA) showed enzymatic activity with p-nitrophenylphosphate as a substrate and was inhibited by PTPase inhibitors vanadate and molybdate. GST::EhPTPA protein selectively dephosphorylates a 130kDa phosphotyrosine-containing protein in trophozoite cell lysates. EhPTPA gene codifies for a 43kDa native protein. Up-regulation of EhPTPA expression suggests that EhPTPA may play an important role in the adaptive response of trophozoites during amoebic liver abscess development.


Assuntos
Disenteria Amebiana/parasitologia , Entamoeba histolytica/enzimologia , Fígado/parasitologia , Proteínas Tirosina Fosfatases/química , Proteínas Tirosina Fosfatases/metabolismo , Sequência de Aminoácidos , Animais , Clonagem Molecular , Cricetinae , Ativação Enzimática , Dados de Sequência Molecular , Proteínas Tirosina Fosfatases/análise , Homologia de Sequência de Aminoácidos , Especificidade da Espécie
14.
Int J Exp Pathol ; 86(5): 323-34, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16191104

RESUMO

Although dengue virus (DV) enters through skin while mosquitoes feed, early contacts remain unexplored regarding the cutaneous viral fate and in situ immune responses. We addressed this by exposing healthy, non-cadaveric, freshly obtained human skin explants to a human DV2 isolate. We demonstrated negative-strand DV-RNA and non-structural protein-1, both suggestive of viral replication in skin. Although control, mock-infected and DV-infected explants showed less (MHC-CII(+)/CD1a(+)/Langerin+) Langerhans cells, deranged morphology and decreased frequency were more apparent in DV-infected explants. Whereas DV+ cells were infrequent in epidermis and completely absent in dermis, some areas of basal epidermis were clearly DV+, presumably keratinocytes, cells where TUNEL positivity revealed apoptosis. Unlike fresh, control and mock-infected skin, DV-infected explants expressed CD80 and CD83, indicative of dendritic cell (DC) activation and maturation, respectively. However, sequential sections indicated that these cells were not DV+, suggesting that activated/mature DCs capable of priming T cells, probably, were not infected. Alternatively, the occasionally infected epidermal DC might not have reached maturation. Interestingly, skin DV infection apparently uncouples the DC activation/maturation process from another crucial DC function, the subsequent migration into dermis. This was suggested, because upon cutaneous DV infection, the few emerging CD83+ (mature) DCs remained within the outer epidermis, while no dermal CD83+ DCs were observed. These paradoxical effects might represent unknown DV subversion strategies. This approach is relatively easy, quick (results in 48 h), economical for developing countries where dengue is re-emerging and advantageous to evaluate in situ viral biology, immunity and immunopathology and potential antiviral strategies.


Assuntos
Células Dendríticas/imunologia , Vírus da Dengue/patogenicidade , Dengue/imunologia , Epiderme/imunologia , Apoptose , Células Dendríticas/virologia , Epiderme/patologia , Epiderme/virologia , Feminino , Humanos , Hibridização In Situ , RNA Viral/análise , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Técnicas de Cultura de Tecidos , Vacinação/métodos , Proteínas não Estruturais Virais/análise , Virologia/métodos , Replicação Viral
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