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1.
Psicol. Educ. (Online) ; (50): 94-103, jan.-jun. 2020.
Article in Portuguese | LILACS, Index Psychology - journals | ID: biblio-1125408

ABSTRACT

O estudo teve por objetivo conhecer a visão e a prática de professores de ciências e alunos de curso de licenciatura em Ciências Biológicas em relação aos distúrbios de aprendizagem e ao fracasso escolar, de modo a compreender os sentidos e significados construídos por eles em relação à crescente atribuição de responsabilidade biológica ao suposto fracasso no ensino. Trata-se de pesquisa qualitativa, que se utilizou de aplicação de questionário e entrevista semiestruturada com professores de escolas pública e particular e com alunos de um curso de graduação/licenciatura de uma universidade pública. Como resultados, é possível identificar a sobreposição em relação ao entendimento e uso de terminologias como "distúrbios", "problemas" e "dificuldades" de aprendizagem, sendo utilizadas pelos professores e estudantes participantes da pesquisa, como sinônimos para designar um processo análogo. Verificou-se a atribuição de causa biológica a qualquer dificuldade ou problema de aprendizado do aluno, ainda que a causa seja, de fato, devido a fatores sociais ou psicológicos. Evidenciou-se o despreparo para com a realização do diagnóstico, bem como desconhecimento em relação às formas de se fazer, atribuindo esse papel a outros profissionais que acreditam estar mais preparados para lidar com esses casos, considerando-se que o tratamento medicamentoso possa ser o mais efetivo. Desse modo, os resultados obtidos demonstram a importância de investigações e elucidações mais profundas a respeito do cotidiano escolar no que se refere às questões atreladas ao processo ensino-aprendizagem e à crescente medicalização de crianças e adolescentes.


The purpose of this study was to understand the vision and practice of science teachers and students of a licentiate degree course in Biological Sciences in relation to learning disorders and school failure, in order to understand the senses and meanings they constructed in relation to the increasing attribution of biological responsibility to the supposed school failure. It is a qualitative research, in which was used a questionnaire application and a semi-structured interview with public and private school teachers and with students of a undergraduate/licentiate course from a public university. As results it is possible to identify the overlap in terms of understanding and use of terminologies such as "disturbs", "problems" and "difficulties" of learning, by teachers and students participating in the research, as synonyms to designate the same process. The attribution of biological cause to any difficulty or learning problem of the student has been verified, even if the cause is, in fact, due to social or psychological factors. The lack of preparation for diagnosis was evidenciated, as well as lack of knowledge about the ways of doing it, attributing this role to other professionals who believe that they are better prepared to assist these cases, considering that drug treatment may be the most effective. Thus, the results obtained demonstrate the importance of investigations and more profound elucidations about the school daily life in relation to the issues linked with the teaching-learning process and the increasing medicalization of children and adolescents.


El estudio tuvo como objetivo conocer la visión y la práctica de los profesores de ciencias y los estudiantes de la licenciatura en Ciencias Biológicas en relación a los trastornos de aprendizaje y fracaso escolar, con el fin de comprender los significados construidos por ellos en relación al crecente aumento de la asignación de la responsabilidad biológica al supuesto fracaso en la enseñanza. Se trata de una investigación cualitativa, en la cual se utilizo la aplicación de cuestionarios y entrevistas semiestructuradas a maestros de escuelas públicas y privadas y a estudiantes en un curso de grado / licenciatura de una universidad pública. Como resultado, es posible identificar la superposición en relación con la comprensión y el uso de terminología como "trastornos", "problemas" y "dificultades" de aprendizaje, siendo utilizados por los profesores y estudiantes que participaron de la encuesta, indistintamente para describir un mismo proceso. Se encontró la asignación de causa biológica a cualquier dificultad o problema de aprendizaje de los estudiantes, aun que la causa sea de hecho, debido a factores sociales o psicológicos. La falta de preparación para realización de diagnóstico se hizo evidente, así como el desconocimiento de formas de hacer, asignando ese papel a otros profesionales que creen estar mejor preparados para hacer frente a estos casos, teniendo en cuenta que el tratamiento farmacológico puede ser más eficaz. Por lo tanto, los resultados demuestran la importancia investigaciones y mejores esclarecimiento sobre el cotidiano de la escuela cuando se trata de cuestiones relacionadas al proceso de enseñanza-aprendizaje y la creciente medicalización de niños y adolescentes.


Subject(s)
Students , Biological Science Disciplines , Medicalization , School Teachers , Academic Failure , Social Factors , Learning , Learning Disabilities , Teaching , Drug Therapy , Faculty
2.
Bio Protoc ; 10(17): e3739, 2020 Sep 05.
Article in English | MEDLINE | ID: mdl-33659399

ABSTRACT

Genetic transformation is crucial for both investigating gene functions and for engineering of crops to introduce new traits. Rice (Oryza sativa L.) is an important model in plant research, since it is the staple food for more than half of the world's population. As a result, numerous transformation methods have been developed for both indica and japonica rice. Since breeders continuously develop new rice varieties, transformation protocols have to be adapted for each new variety. Here we provide an optimized transformation protocol with detailed tips and tricks for a new African variety Komboka using immature embryos. In Komboka, we obtained an apparent transformation rate of up to 48% for GUS/GFP reporter gene constructs using this optimized protocol. This protocol is also applicable for use with other elite indica rice varieties.

3.
Life Sci Alliance ; 1(5): e201800060, 2018 Oct.
Article in English | MEDLINE | ID: mdl-30456377

ABSTRACT

During B-cell activation, the dynamic reorganisation of the cytoskeleton is crucial for multiple cellular responses, such as receptor signalling, cell spreading, antigen internalisation, intracellular trafficking, and antigen presentation. However, the role of intermediate filaments (IFs), which represent a major component of the mammalian cytoskeleton, is not well defined. Here, by using multiple super-resolution microscopy techniques, including direct stochastic optical reconstruction microscopy, we show that IFs in B cells undergo drastic reorganisation immediately upon antigen stimulation and that this reorganisation requires actin and microtubules. Although the loss of vimentin in B cells did not impair B-cell development, receptor signalling, and differentiation, vimentin-deficient B cells exhibit altered positioning of antigen-containing and lysosomal associated membrane protein 1 (LAMP1+) compartments, implying that vimentin may play a role in the fine-tuning of intracellular trafficking. Indeed, vimentin-deficient B cells exhibit impaired antigen presentation and delayed antibody responses in vivo. Thus, our study presents a new perspective on the role of IFs in B-cell activation.

4.
Immunity ; 48(6): 1144-1159.e5, 2018 06 19.
Article in English | MEDLINE | ID: mdl-29884460

ABSTRACT

PKCß-null (Prkcb-/-) mice are severely immunodeficient. Here we show that mice whose B cells lack PKCß failed to form germinal centers and plasma cells, which undermined affinity maturation and antibody production in response to immunization. Moreover, these mice failed to develop plasma cells in response to viral infection. At the cellular level, we have shown that Prkcb-/- B cells exhibited defective antigen polarization and mTORC1 signaling. While altered antigen polarization impaired antigen presentation and likely restricted the potential of GC development, defective mTORC1 signaling impaired metabolic reprogramming, mitochondrial remodeling, and heme biosynthesis in these cells, which altogether overwhelmingly opposed plasma cell differentiation. Taken together, our study reveals mechanistic insights into the function of PKCß as a key regulator of B cell polarity and metabolic reprogramming that instructs B cell fate.


Subject(s)
B-Lymphocytes/immunology , Cell Differentiation/immunology , Lymphocyte Activation/immunology , Plasma Cells/immunology , Protein Kinase C beta/immunology , Animals , Heme/biosynthesis , Mice , Mice, Knockout , Mitochondria/immunology , Mitochondria/metabolism , Plasma Cells/cytology
5.
Cell ; 172(3): 517-533.e20, 2018 01 25.
Article in English | MEDLINE | ID: mdl-29249358

ABSTRACT

B cells constitute an essential line of defense from pathogenic infections through the generation of class-switched antibody-secreting cells (ASCs) in germinal centers. Although this process is known to be regulated by follicular helper T (TfH) cells, the mechanism by which B cells initially seed germinal center reactions remains elusive. We found that NKT cells, a population of innate-like T lymphocytes, are critical for the induction of B cell immunity upon viral infection. The positioning of NKT cells at the interfollicular areas of lymph nodes facilitates both their direct priming by resident macrophages and the localized delivery of innate signals to antigen-experienced B cells. Indeed, NKT cells secrete an early wave of IL-4 and constitute up to 70% of the total IL-4-producing cells during the initial stages of infection. Importantly, the requirement of this innate immunity arm appears to be evolutionarily conserved because early NKT and IL-4 gene signatures also positively correlate with the levels of neutralizing antibodies in Zika-virus-infected macaques. In conclusion, our data support a model wherein a pre-TfH wave of IL-4 secreted by interfollicular NKT cells triggers the seeding of germinal center cells and serves as an innate link between viral infection and B cell immunity.


Subject(s)
B-Lymphocytes/immunology , Germinal Center/immunology , Immunity, Innate , Influenza, Human/immunology , Interleukin-4/genetics , Killer Cells, Natural/immunology , Zika Virus Infection/immunology , Animals , Chickens , Dogs , Germinal Center/cytology , Humans , Interleukin-4/metabolism , Macaca , Macrophages/immunology , Madin Darby Canine Kidney Cells , Mice , Mice, Inbred C57BL
6.
PLoS One ; 12(10): e0185707, 2017.
Article in English | MEDLINE | ID: mdl-28982174

ABSTRACT

Cytokinesis is the last stage in the cell cycle. In prokaryotes, the protein FtsZ guides cell constriction by assembling into a contractile ring-shaped structure termed the Z-ring. Constriction of the Z-ring is driven by the GTPase activity of FtsZ that overcomes the energetic barrier between two protein conformations having different propensities to assemble into polymers. FtsZ is found in psychrophilic, mesophilic and thermophilic organisms thereby functioning at temperatures ranging from subzero to >100°C. To gain insight into the functional adaptations enabling assembly of FtsZ in distinct environmental conditions, we analyzed the energetics of FtsZ function from mesophilic Escherichia coli in comparison with FtsZ from thermophilic Methanocaldococcus jannaschii. Presumably, the assembly may be similarly modulated by temperature for both FtsZ orthologs. The temperature dependence of the first-order rates of nucleotide hydrolysis and of polymer disassembly, indicated an entropy-driven destabilization of the FtsZ-GTP intermediate. This destabilization was true for both mesophilic and thermophilic FtsZ, reflecting a conserved mechanism of disassembly. From the temperature dependence of the critical concentrations for polymerization, we detected a change of opposite sign in the heat capacity, that was partially explained by the specific changes in the solvent-accessible surface area between the free and polymerized states of FtsZ. At the physiological temperature, the assembly of both FtsZ orthologs was found to be driven by a small positive entropy. In contrast, the assembly occurred with a negative enthalpy for mesophilic FtsZ and with a positive enthalpy for thermophilic FtsZ. Notably, the assembly of both FtsZ orthologs is characterized by a critical concentration of similar value (1-2 µM) at the environmental temperatures of their host organisms. These findings suggest a simple but robust mechanism of adaptation of FtsZ, previously shown for eukaryotic tubulin, by adjustment of the critical concentration for polymerization.


Subject(s)
Archaeal Proteins/metabolism , Methanocaldococcus/metabolism , Biopolymers/metabolism , Escherichia coli/genetics , Guanosine Triphosphate/metabolism , Hydrolysis , Kinetics , Methanocaldococcus/genetics , Polymerization , Temperature , Thermodynamics
8.
J Exp Med ; 214(8): 2471-2490, 2017 Aug 07.
Article in English | MEDLINE | ID: mdl-28739603

ABSTRACT

Vaccines remain the most effective tool to prevent infectious diseases. Here, we introduce an in vitro booster vaccination approach that relies on antigen-dependent activation of human memory B cells in culture. This stimulation induces antigen-specific B cell proliferation, differentiation of B cells into plasma cells, and robust antibody secretion after a few days of culture. We validated this strategy using cells from healthy donors to retrieve human antibodies against tetanus toxoid and influenza hemagglutinin (HA) from H1N1 and newly emergent subtypes such as H5N1 and H7N9. Anti-HA antibodies were cross-reactive against multiple subtypes, and some showed neutralizing activity. Although these antibodies may have arisen as a result of previous influenza infection, we also obtained gp120-reactive antibodies from non-HIV-infected donors, indicating that we can generate antibodies without prior antigenic exposure. Overall, our novel approach can be used to rapidly produce therapeutic antibodies and has the potential to assess the immunogenicity of candidate antigens, which could be exploited in future vaccine development.

9.
Science ; 355(6325): 641-647, 2017 02 10.
Article in English | MEDLINE | ID: mdl-28183981

ABSTRACT

Autophagy is important in a variety of cellular and pathophysiological situations; however, its role in immune responses remains elusive. Here, we show that among B cells, germinal center (GC) cells exhibited the highest rate of autophagy during viral infection. In contrast to mechanistic target of rapamycin complex 1-dependent canonical autophagy, GC B cell autophagy occurred predominantly through a noncanonical pathway. B cell stimulation was sufficient to down-regulate canonical autophagy transiently while triggering noncanonical autophagy. Genetic ablation of WD repeat domain, phosphoinositide-interacting protein 2 in B cells alone enhanced this noncanonical autophagy, resulting in changes of mitochondrial homeostasis and alterations in GC and antibody-secreting cells. Thus, B cell activation prompts a temporal switch from canonical to noncanonical autophagy that is important in controlling B cell differentiation and fate.


Subject(s)
Autophagy/immunology , B-Lymphocytes/immunology , B-Lymphocytes/virology , Virus Diseases/immunology , Animals , Down-Regulation , Germinal Center/immunology , Germinal Center/virology , Lymphocyte Activation , Mechanistic Target of Rapamycin Complex 1 , Mice , Mice, Inbred C57BL , Mice, Knockout , Microtubule-Associated Proteins/genetics , Microtubule-Associated Proteins/metabolism , Mitochondria/metabolism , Multiprotein Complexes/metabolism , TOR Serine-Threonine Kinases/metabolism , WD40 Repeats/genetics
10.
Front Immunol ; 6: 596, 2015.
Article in English | MEDLINE | ID: mdl-26635810

ABSTRACT

The induction of donor-specific transplant tolerance is one of the main goals of modern immunology. Establishment of a mixed chimerism state in the transplant recipient has proven to be a suitable strategy for the induction of long-term allograft tolerance; however, current experimental recipient preconditioning protocols have many side effects, and are not feasible for use in future therapies. In order to improve the current mixed chimerism induction protocols, we developed a non-myeloablative bone-marrow transplant (NM-BMT) protocol using retinoic acid (RA)-induced alloantigen-specific Tregs, clinically available immunosuppressive drugs, and lower doses of irradiation. We demonstrate that RA-induced alloantigen-specific Tregs in addition to a NM-BMT protocol generates stable mixed chimerism and induces tolerance to allogeneic secondary skin allografts in mice. Therefore, the establishment of mixed chimerism through the use of donor-specific Tregs rather than non-specific immunosuppression could have a potential use in organ transplantation.

11.
Dolor ; 25(63): 18-24, jul. 2015. tab
Article in Spanish | LILACS | ID: biblio-907603

ABSTRACT

Introducción: el dolor crónico es una condición que afecta a 1 de cada 5 personas en el mundo, comprometiendo diferentes áreas de la calidad de vida. El cuestionario para graduación de dolor crónico (CGDC) fue desarrollado como una forma de evaluar y monitorear a estos pacientes, con altos niveles de fiabilidad y validez. Objetivos: Desarrollar una versión española del CGDC, adaptado culturalmente a Chile y determinar su validez y fiabilidad, en el Hospital Clínico de la Universidad de Chile. Material y métodos: El cuestionario fue traducido y adaptado culturalmente de acuerdo a las recomendaciones internacionales. Se aplicó SF-36 v2.0 en 130 pacientes condolor musculoesquelético crónico (más de 6 meses). La fiabilidad se calculó con Alfa de Cronbach y el índice de validez se evaluó mediante la comparación de las respuestas de la CGDC para cada categoría con las subescalas del SF-36 v.2. Resultados: La versión chilena de la CGDC fue válida. Se obtuvieron altos niveles de confiabilidad con alfa de Cronbach> 0,7. Se observaron correlaciones significativas del SF -36,especialmente con las subescalas que tienen alta capacidad de medir el dolor y la salud física (p <0,01). Conclusiones: Los resultados presentados aquí confirman la fiabilidad y validez de la versión chilena del CGDC en la evaluación de pacientes con dolor musculoesquelético crónico.


Introduction: chronic pain is a condition that affectss 1 in every 5 people in the world, compromising different areas of quality of life. The Chronic Pain Graded questionnaire (CPG) was developed as a form to assess and monitor these patients, with high levels of reliability and validity. Objectives: To develop a spanish version of the chronic pain graded questionnaire, culturally adapted to Chile determine its reliability and convergent construct validity , in the University of Chile Clinical Hospital. Materials and Methods: The chronic pain graded questionnaire was translated and culturally adapted accordingt o international recommendations. It was applied with SF -36 v2.0 questionnaire in 130 patients with chronic musculoskeletal pain (more than 6 months). The reliability was calculated with de Alpha the Cronbach Index and de validity was assessed by comparing the responses of the CPG for each category with the subscales of SF-36 v.2. Results: The Chilean version of the CBDC was valid. High levels of reliability was obtained with Cronbach’s alpha > 0.7. Compared with the SF -36 significant correlations were observed, especially with the SF -36 subscales having high ability to measure pain and physical health ( P < 0.01). Conclusions: The results presented here confirm the reliability and validity of the Chilean version of the chronic pain graded questionnaire in the evaluation of patients with chronic musculoskeletal pain.


Subject(s)
Humans , Male , Female , Adult , Middle Aged , Aged , Aged, 80 and over , Young Adult , Musculoskeletal Diseases/complications , Musculoskeletal Pain/diagnosis , Pain Measurement/instrumentation , Surveys and Questionnaires , Chile , Chronic Disease , Reproducibility of Results , Self Report , Translations
12.
Exp Mol Pathol ; 98(1): 119-23, 2015 Feb.
Article in English | MEDLINE | ID: mdl-25579181

ABSTRACT

OBJECTIVE: To analyze the presence of HPV-DNA and TIMP-2 gene methylation in cervical precursor and invasive lesions, as well as to study the associations among the latter, the presence of HPV-DNA, and the clinical evolution of such lesions. METHODS: Cross-sectional study that includes 49 biopsy or brush smear samples from women with a normal cervix, LSIL, HSIL, microinvasive carcinoma and invasive carcinoma. The presence of HPV-DNA and specific methylation was analyzed using PCR. Thirty-eight biopsy samples for HSIL, microinvasive carcinoma and frank invasive carcinoma as well as 11 brush smear samples for LSIL and normal cervices were analyzed. RESULTS: TIMP-2 gene methylation was detected in 86.8% (33/38) of the samples from the group with lesions and 50% (4/8) of the normal samples (p=0.03). HPV-DNA was detected in 81.6% (31/38) of the samples from the group with lesions and 25% (2/8) of the normal samples (p=0.003). HPV-DNA was more frequent in the methylated samples (50%), and the group with methylation had a higher risk of unfavorable evolution than the group without methylation; however, such observations were not statistically significant (p=0.19). CONCLUSION: TIMP-2 gene methylation and the presence of HPV-DNA were characteristic of the group with cervical lesions. Methylation was not associated with the presence of HPV-DNA or an unfavorable clinical evolution.


Subject(s)
Biomarkers, Tumor/genetics , Carcinoma, Squamous Cell/genetics , DNA Methylation , Papillomavirus Infections/genetics , Tissue Inhibitor of Metalloproteinase-2/genetics , Uterine Cervical Dysplasia/genetics , Uterine Cervical Neoplasms/genetics , Adult , Aged , Carcinoma, Squamous Cell/pathology , Carcinoma, Squamous Cell/virology , Cross-Sectional Studies , DNA, Viral/genetics , Female , Follow-Up Studies , Humans , Middle Aged , Neoplasm Invasiveness , Papillomaviridae/genetics , Papillomavirus Infections/pathology , Papillomavirus Infections/virology , Polymerase Chain Reaction , Prognosis , Uterine Cervical Neoplasms/pathology , Uterine Cervical Neoplasms/virology , Uterine Cervical Dysplasia/pathology , Uterine Cervical Dysplasia/virology
13.
Exp Mol Pathol ; 98(2): 308-11, 2015 Apr.
Article in English | MEDLINE | ID: mdl-25579180

ABSTRACT

BACKGROUND: DNA methylation is the most important epigenetic change involved in the control of gene expression in human cells. Methylation of the p16(INK4a) gene occurs early in the development of cervical cancer. Low-grade squamous intraepithelial lesions (LSILs) are prevalent, and their behavior is variable. OBJECTIVE: To identify the HPV DNA type, detect the methylation status of the p16(INK4A) gene, and analyze their association with the cytological evolution of LSIL over a period of two years. METHODS: We conducted a cohort study with 40 participants. Cervical scrapings were collected for cytological and molecular analysis. HPV DNA detection and typing were performed by means of polymerase chain reaction (PCR) and restriction fragment length polymorphism (RFLP). Methylation-specific PCR was performed to detect methylation. RESULTS: HPV DNA was detected in 87% of the cases, and type 16 was the most frequent type. Methylation was detected in 11% of the cases and did not exhibit a significant correlation with the HPV type. Unfavorable cytological evolution exhibited a significant association with the presence of methylation. CONCLUSION: HPV 16 was the most frequently detected type of HPV in LSIL. Methylation of the p16(INK4A) gene was infrequent and occurred independent of the presence of HPV DNA. Methylation of the p16(INK4a) gene exhibited a significant correlation with persistence/progression of LSIL.


Subject(s)
Cyclin-Dependent Kinase Inhibitor p16/genetics , DNA Methylation/genetics , Human papillomavirus 16/genetics , Squamous Intraepithelial Lesions of the Cervix/genetics , Uterine Cervical Dysplasia/genetics , Adult , Biomarkers, Tumor , Cohort Studies , DNA, Viral/genetics , Female , Humans , Middle Aged , Papillomavirus Infections/diagnosis , Squamous Intraepithelial Lesions of the Cervix/virology , Young Adult , Uterine Cervical Dysplasia/virology
14.
Eur J Immunol ; 45(2): 452-63, 2015 Feb.
Article in English | MEDLINE | ID: mdl-25381698

ABSTRACT

CD4(+) CD25(+) Foxp3(+) regulatory T (Treg) cells mediate immunological self-tolerance and suppress immune responses. Retinoic acid (RA), a natural metabolite of vitamin A, has been reported to enhance the differentiation of Treg cells in the presence of TGF-ß. In this study, we show that the co-culture of naive T cells from C57BL/6 mice with allogeneic antigen-presenting cells (APCs) from BALB/c mice in the presence of TGF-ß, RA, and IL-2 resulted in a striking enrichment of Foxp3(+) T cells. These RA in vitro-induced regulatory T (RA-iTreg) cells did not secrete Th1-, Th2-, or Th17-related cytokines, showed a nonbiased homing potential, and expressed several cell surface molecules related to Treg-cell suppressive potential. Accordingly, these RA-iTreg cells suppressed T-cell proliferation and inhibited cytokine production by T cells in in vitro assays. Moreover, following adoptive transfer, RA-iTreg cells maintained Foxp3 expression and their suppressive capacity. Finally, RA-iTreg cells showed alloantigen-specific immunosuppressive capacity in a skin allograft model in immunodeficient mice. Altogether, these data indicate that functional and stable allogeneic-specific Treg cells may be generated using TGF-ß, RA, and IL-2. Thus, RA-iTreg cells may have a potential use in the development of more effective cellular therapies in clinical transplantation.


Subject(s)
Graft Rejection/prevention & control , Skin Transplantation , Skin/immunology , T-Lymphocytes, Regulatory/immunology , Tretinoin/pharmacology , Adoptive Transfer , Allografts , Animals , Coculture Techniques , Dendritic Cells/cytology , Dendritic Cells/drug effects , Dendritic Cells/immunology , Forkhead Transcription Factors/genetics , Forkhead Transcription Factors/immunology , Gene Expression , Graft Survival , Interleukin-2/pharmacology , Mice , Mice, Inbred BALB C , Mice, Inbred C57BL , Mice, Knockout , Ovalbumin/administration & dosage , Skin/cytology , Spleen/cytology , Spleen/immunology , T-Lymphocytes, Regulatory/cytology , T-Lymphocytes, Regulatory/drug effects , T-Lymphocytes, Regulatory/transplantation , Transforming Growth Factor beta/pharmacology
15.
J. physiol. biochem ; 70(2): 487-496, jun. 2014.
Article in English | IBECS | ID: ibc-122969

ABSTRACT

The aim of this study was to assess whether alfa-tocopherol administration prevented alterations in the ectonucleotidase activities and platelet aggregation induced by high-fat diet in rats. Thus, we examined four groups of male rats which received standard diet, high-fat diet (HFD), α-tocopherol (α-Toc), and high-fat diet plus α-tocopherol. HFD was administered ad libitum and α-Toc by gavage using a dose of 50 mg/kg. After 3 months of treatment, animals were submitted to euthanasia, and blood samples were collected for biochemical assays. Results demonstrate that NTPDase, ectonucleotide pyrophosphatase/phosphodiesterase, and 5'-nucleotidase activities were significantly decreased in platelets of HFD group, while that adenosine deaminase (ADA) activity was significantly increased in this group in comparison to the other groups (P < 0.05). When rats that received HFD were treated with α-Toc, the activities of these enzymes were similar to the control, but ADA activity was significantly increased in relation to the control and α-Toc group (P < 0.05). HFD group showed an increased in platelet aggregation in comparison to the other groups, and treatment with α-Toc significantly reduced platelet aggregation in this group. These findings demonstrated that HFD alters platelet aggregation and purinergic signaling in the platelets and that treatment with α-Toc was capable of modulating the adenine nucleotide hydrolysis in this experimental condition


No disponible


Subject(s)
Animals , Rats , Cyclic AMP Receptor Protein , Nucleotides/physiology , Platelet Aggregation , alpha-Tocopherol/pharmacokinetics , Dietary Fats/metabolism , Receptors, Purinergic , Adenine Nucleotides/physiology , Disease Models, Animal
16.
J Physiol Biochem ; 70(2): 487-96, 2014 Jun.
Article in English | MEDLINE | ID: mdl-24623516

ABSTRACT

The aim of this study was to assess whether α-tocopherol administration prevented alterations in the ectonucleotidase activities and platelet aggregation induced by high-fat diet in rats. Thus, we examined four groups of male rats which received standard diet, high-fat diet (HFD), α-tocopherol (α-Toc), and high-fat diet plus α-tocopherol. HFD was administered ad libitum and α-Toc by gavage using a dose of 50 mg/kg. After 3 months of treatment, animals were submitted to euthanasia, and blood samples were collected for biochemical assays. Results demonstrate that NTPDase, ectonucleotide pyrophosphatase/phosphodiesterase, and 5'-nucleotidase activities were significantly decreased in platelets of HFD group, while that adenosine deaminase (ADA) activity was significantly increased in this group in comparison to the other groups (P < 0.05). When rats that received HFD were treated with α-Toc, the activities of these enzymes were similar to the control, but ADA activity was significantly increased in relation to the control and α-Toc group (P < 0.05). HFD group showed an increased in platelet aggregation in comparison to the other groups, and treatment with α-Toc significantly reduced platelet aggregation in this group. These findings demonstrated that HFD alters platelet aggregation and purinergic signaling in the platelets and that treatment with α-Toc was capable of modulating the adenine nucleotide hydrolysis in this experimental condition.


Subject(s)
Diet, High-Fat , Nucleotides/metabolism , Platelet Aggregation , alpha-Tocopherol/pharmacology , Animals , Rats
17.
Eur J Cancer ; 49(16): 3450-61, 2013 Nov.
Article in English | MEDLINE | ID: mdl-23886586

ABSTRACT

BACKGROUND: Human papillomavirus (HPV) contribution in vulvar intraepithelial lesions (VIN) and invasive vulvar cancer (IVC) is not clearly established. This study provides novel data on HPV markers in a large series of VIN and IVC lesions. METHODS: Histologically confirmed VIN and IVC from 39 countries were assembled at the Catalan Institute of Oncology (ICO). HPV-DNA detection was done by polymerase chain reaction using SPF-10 broad-spectrum primers and genotyping by reverse hybridisation line probe assay (LiPA25) (version 1). IVC cases were tested for p16(INK4a) by immunohistochemistry (CINtec histology kit, ROCHE). An IVC was considered HPV driven if both HPV-DNA and p16(INK4a) overexpression were observed simultaneously. Data analyses included algorithms allocating multiple infections to calculate type-specific contribution and logistic regression models to estimate adjusted prevalence (AP) and its 95% confidence intervals (CI). RESULTS: Of 2296 cases, 587 were VIN and 1709 IVC. HPV-DNA was detected in 86.7% and 28.6% of the cases respectively. Amongst IVC cases, 25.1% were both HPV-DNA and p16(INK4a) positive. IVC cases were largely keratinising squamous cell carcinoma (KSCC) (N=1234). Overall prevalence of HPV related IVC cases was highest in younger women for any histological subtype. SCC with warty or basaloid features (SCC_WB) (N=326) were more likely to be HPV and p16(INK4a) positive (AP=69.5%, CI=63.6-74.8) versus KSCC (AP=11.5%, CI=9.7-13.5). HPV 16 was the commonest type (72.5%) followed by HPV 33 (6.5%) and HPV 18 (4.6%). Enrichment from VIN to IVC was significantly high for HPV 45 (8.5-fold). CONCLUSION: Combined data from HPV-DNA and p16(INK4a) testing are likely to represent a closer estimate of the real fraction of IVC induced by HPV. Our results indicate that HPV contribution in invasive vulvar cancer has probably been overestimated. HPV 16 remains the major player worldwide.


Subject(s)
Carcinoma in Situ/virology , Papillomaviridae/genetics , Papillomavirus Infections/virology , Vulvar Neoplasms/virology , Adult , Algorithms , Biomarkers, Tumor/analysis , Carcinoma in Situ/chemistry , Carcinoma in Situ/pathology , Cross-Sectional Studies , Cyclin-Dependent Kinase Inhibitor p16/analysis , DNA Probes, HPV , Female , Genotype , Human Papillomavirus DNA Tests , Humans , Immunohistochemistry , Logistic Models , Middle Aged , Neoplasm Invasiveness , Papillomaviridae/classification , Papillomavirus Infections/complications , Papillomavirus Infections/diagnosis , Polymerase Chain Reaction , Predictive Value of Tests , Retrospective Studies , Up-Regulation , Vulvar Neoplasms/chemistry , Vulvar Neoplasms/pathology
18.
Clin Dev Immunol ; 2013: 210506, 2013.
Article in English | MEDLINE | ID: mdl-23762087

ABSTRACT

One of the greatest advances in medicine during the past century is the introduction of organ transplantation. This therapeutic strategy designed to treat organ failure and organ dysfunction allows to prolong the survival of many patients that are faced with no other treatment option. Today, organ transplantation between genetically dissimilar individuals (allogeneic grafting) is a procedure widely used as a therapeutic alternative in cases of organ failure, hematological disease treatment, and some malignancies. Despite the potential of organ transplantation, the administration of immunosuppressive drugs required for allograft acceptance induces severe immunosuppression in transplanted patients, which leads to serious side effects such as infection with opportunistic pathogens and the occurrence of neoplasias, in addition to the known intrinsic toxicity of these drugs. To solve this setback in allotransplantation, researchers have focused on manipulating the immune response in order to create a state of tolerance rather than unspecific immunosuppression. Here, we describe the different treatments and some of the novel immunotherapeutic strategies undertaken to induce transplantation tolerance.


Subject(s)
Graft Rejection/prevention & control , Immunologic Factors/therapeutic use , Organ Transplantation , Transplantation Tolerance/drug effects , Cytokines/biosynthesis , Cytokines/immunology , Dendritic Cells/immunology , Dendritic Cells/pathology , Graft Rejection/immunology , Graft Rejection/pathology , Graft Survival/drug effects , Graft Survival/immunology , Humans , Immunosuppression Therapy , Immunosuppressive Agents/adverse effects , Macrophages/immunology , Macrophages/pathology , T-Lymphocytes/immunology , T-Lymphocytes/pathology , Transplantation, Homologous
19.
Biomed Pharmacother ; 67(3): 203-8, 2013 Apr.
Article in English | MEDLINE | ID: mdl-23433854

ABSTRACT

The relation between adenine nucleotides and cancer has already been described in literature. Considering that the enzymes ectonucleotide pyrophosphatase/phosphodiesterase (E-NPP) and adenosine deaminase (ADA) act together to control nucleotide levels, we aimed to investigate the role of these enzymes in prostate cancer (PCa). E-NPP and ADA activities were determined in serum and platelets of PCa patients and controls. We also verified the influence of the Gleason score, bone metastasis and treatment in the enzyme activities. Platelets and serum E-NPP activity increased, whereas ADA activity in serum decreased in PCa patients. In addition, Gleason score, metastasis and treatment influenced E-NPP and ADA activities. We may propose that E-NPP and ADA are involved in the development of PCa. Moreover, E-NPP and ADA activities are modified in PCa patients with distinct Gleason score, with bone metastasis, as well as in patients under treatment.


Subject(s)
Adenosine Deaminase/metabolism , Bone Neoplasms/enzymology , Bone Neoplasms/pathology , Phosphoric Diester Hydrolases/metabolism , Prostatic Neoplasms/enzymology , Prostatic Neoplasms/pathology , Pyrophosphatases/metabolism , Aged , Aged, 80 and over , Biomarkers, Tumor/metabolism , Bone Neoplasms/secondary , Bone Neoplasms/therapy , Down-Regulation/physiology , Female , Humans , Male , Middle Aged , Neoplasm Grading , Phosphoric Diester Hydrolases/blood , Prostatic Neoplasms/therapy , Pyrophosphatases/blood , Treatment Outcome
20.
Immunology ; 139(1): 61-71, 2013 May.
Article in English | MEDLINE | ID: mdl-23278668

ABSTRACT

T helper type 17 (Th17) lymphocytes are found in high frequency in tumour-burdened animals and cancer patients. These lymphocytes, characterized by the production of interleukin-17 and other pro-inflammatory cytokines, have a well-defined role in the development of inflammatory and autoimmune pathologies; however, their function in tumour immunity is less clear. We explored possible opposing anti-tumour and tumour-promoting functions of Th17 cells by evaluating tumour growth and the ability to promote tumour infiltration of myeloid-derived suppressor cells (MDSC), regulatory T cells and CD4(+)  interferon-γ(+) cells in a retinoic acid-like orphan receptor γt (RORγt) -deficient mouse model. A reduced percentage of Th17 cells in the tumour microenvironment in RORγt-deficient mice led to enhanced tumour growth, that could be reverted by adoptive transfer of Th17 cells. Differences in tumour growth were not associated with changes in the accumulation or suppressive function of MDSC and regulatory T cells but were related to a decrease in the proportion of CD4(+) T cells in the tumour. Our results suggest that Th17 cells do not affect the recruitment of immunosuppressive populations but favour the recruitment of effector Th1 cells to the tumour, thereby promoting anti-tumour responses.


Subject(s)
Immune Tolerance , Neoplasms/immunology , Th1 Cells/immunology , Th17 Cells/immunology , Animals , Cell Line, Tumor , Mice , Mice, Mutant Strains , Neoplasms/genetics , Neoplasms/pathology , Nuclear Receptor Subfamily 1, Group F, Member 3/genetics , Nuclear Receptor Subfamily 1, Group F, Member 3/immunology , Th1 Cells/pathology , Th17 Cells/pathology
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