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1.
Sci Rep ; 9(1): 8621, 2019 06 13.
Artigo em Inglês | MEDLINE | ID: mdl-31197225

RESUMO

The current global malaria control and elimination agenda requires development of additional effective disease intervention tools. Discovery and characterization of relevant parasite antigens is important for the development of new diagnostics and transmission monitoring tools and for subunit vaccine development. This study assessed the natural antibody response profile of seven novel Plasmodium falciparum pre-erythrocytic antigens and their potential association with protection against clinical malaria. Antigen-specific antibody levels in plasma collected at six time points from a longitudinal cohort of one-to-five year old children resident in a seasonal malaria transmission area of northern Ghana were assessed by ELISA. Antibody levels were compared between parasite-positive and parasite-negative individuals and the association of antibody levels with malaria risk assessed using a regression model. Plasma antibody levels against five of the seven antigens were significantly higher in parasite-positive children compared to parasite-negative children, especially during low transmission periods. None of the antigen-specific antibodies showed an association with protection against clinical malaria. The study identified five of the seven antigens as markers of exposure to malaria, and these will have relevance for the development of disease diagnostic and monitoring tools. The vaccine potential of these antigens requires further assessment.


Assuntos
Antígenos de Protozoários/imunologia , Malária Falciparum/imunologia , Malária Falciparum/parasitologia , Plasmodium falciparum/imunologia , Anticorpos Antiprotozoários/imunologia , Pré-Escolar , Estudos de Coortes , Epitopos/imunologia , Gana , Humanos , Lactente , Modelos Lineares , Estudos Longitudinais , Parasitemia/imunologia , Parasitemia/parasitologia
2.
PLoS One ; 14(1): e0210252, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30673723

RESUMO

The development of a sterilizing vaccine against malaria remains one of the highest priorities for global health research. While sporozoite vaccines targeting the pre-erythrocytic stage show great promise, it has not been possible to maintain efficacy long-term, likely due to an inability of these vaccines to maintain effector memory T cell responses in the liver. Vaccines based on human cytomegalovirus (HCMV) might overcome this limitation since vectors based on rhesus CMV (RhCMV), the homologous virus in rhesus macaques (RM), elicit and indefinitely maintain high frequency, non-exhausted effector memory T cells in extralymphoid tissues, including the liver. Moreover, RhCMV strain 68-1 elicits CD8+ T cells broadly recognizing unconventional epitopes exclusively restricted by MHC-II and MHC-E. To evaluate the potential of these unique immune responses to protect against malaria, we expressed four Plasmodium knowlesi (Pk) antigens (CSP, AMA1, SSP2/TRAP, MSP1c) in RhCMV 68-1 or in Rh189-deleted 68-1, which additionally elicits canonical MHC-Ia-restricted CD8+ T cells. Upon inoculation of RM with either of these Pk Ag expressing RhCMV vaccines, we obtained T cell responses to each of the four Pk antigens. Upon challenge with Pk sporozoites we observed a delayed appearance of blood stage parasites in vaccinated RM consistent with a 75-80% reduction of parasite release from the liver. Moreover, the Rh189-deleted RhCMV/Pk vectors elicited sterile protection in one RM. Once in the blood, parasite growth was not affected. In contrast to T cell responses induced by Pk infection, RhCMV vectors maintained sustained T cell responses to all four malaria antigens in the liver post-challenge. The delayed appearance of blood stage parasites is thus likely due to a T cell-mediated inhibition of liver stage parasite development. As such, this vaccine approach can be used to efficiently test new T cell antigens, improve current vaccines targeting the liver stage and complement vaccines targeting erythrocytic antigens.


Assuntos
Antígenos de Protozoários/imunologia , Citomegalovirus/genética , Vacinas Antimaláricas/imunologia , Malária/imunologia , Parasitemia/imunologia , Plasmodium knowlesi/imunologia , Esporozoítos/imunologia , Animais , Anopheles/imunologia , Anopheles/parasitologia , Feminino , Vetores Genéticos/administração & dosagem , Memória Imunológica , Fígado/imunologia , Fígado/parasitologia , Macaca mulatta , Malária/sangue , Malária/parasitologia , Malária/prevenção & controle , Masculino , Parasitemia/sangue , Parasitemia/parasitologia , Parasitemia/prevenção & controle , Plasmodium knowlesi/genética , Proteínas de Protozoários/imunologia , Linfócitos T/imunologia , Linfócitos T/parasitologia
3.
BMC Cancer ; 17(1): 822, 2017 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-29207962

RESUMO

BACKGROUND: Beyond survival of nowadays >80%, modern childhood cancer treatment strives to preserve long-term health and quality of life. However, the majority of today's survivors suffer from short- and long-term adverse effects such as cardiovascular and pulmonary diseases, obesity, osteoporosis, fatigue, depression, and reduced physical fitness and quality of life. Regular exercise can play a major role to mitigate or prevent such late-effects. Despite this, there are no data on the effects of regular exercise in childhood cancer survivors from randomized controlled trials (RCTs). Primary outcome of the current RCT is therefore the effect of a 12-months exercise program on a composite cardiovascular disease risk score in childhood cancer survivors. Secondary outcomes are single cardiovascular disease risk factors, glycaemic control, bone health, body composition, physical fitness, physical activity, quality of life, mental health, fatigue and adverse events (safety). METHODS: A total of 150 childhood cancer survivors aged ≥16 years and diagnosed ≥5 years prior to the study are recruited from Swiss paediatric oncology clinics. Following the baseline assessments patients are randomized 1:1 into an intervention and control group. Thereafter, they are seen at month 3, 6 and 12 for follow-up assessments. The intervention group is asked to add ≥2.5 h of intense physical activity/week, including 30 min of strength building and 2 h of aerobic exercises. In addition, they are told to reduce screen time by 25%. Regular consulting by physiotherapists, individual web-based activity diaries, and pedometer devices are used as motivational tools for the intervention group. The control group is asked to keep their physical activity levels constant. DISCUSSION: The results of this study will show whether a partially supervised exercise intervention can improve cardiovascular disease risk factors, bone health, body composition, physical activity and fitness, fatigue, mental health and quality of life in childhood cancer survivors. If the program will be effective, all relevant information of the SURfit physical activity intervention will be made available to interested clinics that treat and follow-up childhood cancer patients to promote exercise in their patients. TRIAL REGISTRATION: Prospectively registered in clinicaltrials.gov [ NCT02730767 ], registration date: 10.12.2015.


Assuntos
Sobreviventes de Câncer , Doenças Cardiovasculares/prevenção & controle , Adolescente , Adulto , Exercício Físico , Terapia por Exercício , Humanos , Aptidão Física , Qualidade de Vida , Ensaios Clínicos Controlados Aleatórios como Assunto , Fatores de Risco , Adulto Jovem
4.
Oncotarget ; 6(5): 3306-18, 2015 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-25650658

RESUMO

Inflammation contributes to important traits that cancer cells acquire during malignant progression. Gene array data recently identified upregulation of interferon-induced protein with tetratricopeptide repeats 3 (IFIT3) in aggressive pancreatic cancer cells. IFIT3 belongs to the group of interferon stimulated genes (ISG), can be induced by several cellular stress stimuli and by its tetratricopeptide repeats interacts with a multitude of cellular proteins. Upregulation of IFIT3 was confirmed in the aggressive pancreatic cancer cell line L3.6pl compared with its less aggressive cell line of origin, COLO357FG. Transgenic induction of IFIT3 expression in COLO357FG resulted in greater mass of orthotopic tumors and higher prevalence of metastases. Several important traits that mediate malignancy were altered by IFIT3: increased VEGF and IL-6 secretion, chemoresistance and decreased starvation-induced apoptosis. IFIT3 showed binding to JNK and STAT1, the latter being an important inducer of IFIT3 expression. Despite still being alterable by "classical" IFN or NFκB signaling, our findings indicate constitutive - possibly auto-regulated - upregulation of IFIT3 in L3.6pl without presence of an adequate inflammatory stimulus. The transcription factor SOX9, which is linked to regulation of hypoxia-related genes, was identified as a key mediator of upregulation of the oncogene IFIT3 and thereby sustaining a "pseudoinflammatory" cellular condition.


Assuntos
Adenocarcinoma/metabolismo , Inflamação/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Neoplasias Pancreáticas/metabolismo , Adenocarcinoma/genética , Adenocarcinoma/secundário , Animais , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Resistencia a Medicamentos Antineoplásicos , Regulação Neoplásica da Expressão Gênica , Humanos , Inflamação/genética , Inflamação/patologia , Mediadores da Inflamação/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/genética , Masculino , Camundongos Endogâmicos BALB C , Camundongos Nus , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/patologia , Fenótipo , Fatores de Transcrição SOX9/genética , Fatores de Transcrição SOX9/metabolismo , Transdução de Sinais/efeitos dos fármacos , Transfecção , Regulação para Cima
5.
Target Oncol ; 10(4): 535-48, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25639539

RESUMO

Our preliminary studies identified a small population side population (SP) cells in pancreatic cancer cells with stem cell-like properties, which were able to induce fast and aggressive tumor formation in nude mice. Gene expression analysis showed a significant difference in the expression of more than 1,300 genes in SP cells, among which a highly significant difference in microRNA expression of miR-21 and miR-221 between SP and NSP cells was identified. SP cells were identified and characterized by flow cytometry using Hoechst 33342 dye staining from a highly metastatic human pancreatic cancer cell line (L3.6pl). Antagomir transfection was performed using miRNA-21 and miRNA-221 antisense oligonucleotides (ASOs) and followed by detection of cell apoptosis, cell cycle progression, chemosensitivity, and invasion. Sorted SP cells from gemcitabine-resistant L3.6pl cells (L3.6pl(Gres)-SP) cells were orthotopically implanted in nude mice with or without miRNA-21 and miRNA-221 ASOs mono- and combination therapy. The administration of antagomir-21 and antagomir-221 significantly reduced the SP cell fraction, decreased SP cell differentiation, and downstream gene regulation, and thereby induced reduction of L3.6pl cell proliferation, invasion, and chemoresistance against gemcitabine and 5-Fluorouracil. Combination of ASOs therapy against miRNA-21 and miRNA-221 significantly inhibited primary tumor growth and metastasis compared to single antagomir treatment, especially, in L3.6plGres-SP-induced pancreatic tumor growth in vivo. These findings further indicate that the inhibition of miR-21 and miR-221 appear particularly suitable to target stem-like subpopulations and address their specific biological function to promote tumor progression in pancreatic cancer.


Assuntos
MicroRNAs/antagonistas & inibidores , Células-Tronco Neoplásicas/fisiologia , Oligonucleotídeos Antissenso/administração & dosagem , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/terapia , Animais , Carcinogênese/genética , Diferenciação Celular/genética , Linhagem Celular Tumoral , Proliferação de Células/genética , Resistencia a Medicamentos Antineoplásicos , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , MicroRNAs/genética , MicroRNAs/metabolismo , Metástase Neoplásica , Células-Tronco Neoplásicas/patologia , Oligonucleotídeos Antissenso/genética , Neoplasias Pancreáticas/patologia , Transfecção , Regulação para Cima , Ensaios Antitumorais Modelo de Xenoenxerto
6.
Target Oncol ; 10(2): 215-27, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24950733

RESUMO

Cancer stem cells (CSCs) have been proposed to underlie the initiation and maintenance of tumor growth and the development of chemoresistance in solid tumors. The identification and role of these important cells in pancreatic cancer remains controversial. Here, we isolate side population (SP) cells from the highly aggressive and metastatic human pancreatic cancer cell line L3.6pl and evaluate their potential role as models for CSCs. SP cells were isolated following Hoechst 33342 staining of L3.6pl cells. SP, non-SP, and unsorted L3.6pl cells were orthotopically xenografted into the pancreas of nude mice and tumor growth observed. RNA was analyzed by whole genome array and pathway mapping was performed. Drug resistant variants of L3.6pl were developed and examined for SP proportions and evaluated for surface expression of known CSC markers. A distinct SP with the ability to self-renew and differentiate into non-SP cells was isolated from L3.6pl (0.9 % ± 0.22). SP cells showed highly tumorigenic and metastatic characteristics after orthotopic injection. Transcriptomic analysis identified modulation of gene networks linked to tumorigenesis, differentiation, and metastasization in SP cells relative to non-SP cells. Wnt, NOTCH, and EGFR signaling pathways associated with tumor stem cells were altered in SP cells. When cultured with increasing concentrations of gemcitabine, the proportion of SP cells, ABCG2(+), and CD24(+) cells were significantly enriched, whereas 5-fluorouracil (5-FU) treatment lowered the percentage of SP cells. SP cells were distinct from cells positive for previously postulated pancreatic CSC markers. The Hoechst-induced side population in L3.6pl cells comprises a subset of tumor cells displaying aggressive growth and metastasization, increased gemcitabine-, but not 5-FU resistance. The cells may act as a partial model for CSC biology.


Assuntos
Adenocarcinoma/tratamento farmacológico , Antimetabólitos Antineoplásicos/farmacologia , Desoxicitidina/análogos & derivados , Resistencia a Medicamentos Antineoplásicos , Fluoruracila/farmacologia , Células-Tronco Neoplásicas/efeitos dos fármacos , Neoplasias Pancreáticas/tratamento farmacológico , Células da Side Population/efeitos dos fármacos , Adenocarcinoma/genética , Adenocarcinoma/metabolismo , Adenocarcinoma/secundário , Animais , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Separação Celular , Desoxicitidina/farmacologia , Resistencia a Medicamentos Antineoplásicos/genética , Perfilação da Expressão Gênica/métodos , Regulação Neoplásica da Expressão Gênica , Redes Reguladoras de Genes , Humanos , Masculino , Camundongos Endogâmicos BALB C , Camundongos Nus , Células-Tronco Neoplásicas/metabolismo , Células-Tronco Neoplásicas/patologia , Análise de Sequência com Séries de Oligonucleotídeos , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/patologia , Fenótipo , Células da Side Population/metabolismo , Células da Side Population/patologia , Transdução de Sinais/efeitos dos fármacos , Fatores de Tempo , Ensaios Antitumorais Modelo de Xenoenxerto , Gencitabina
7.
Pediatrics ; 129(2): e529-34, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22232309

RESUMO

Clinical presentation of hypopituitarism in the neonate may be variable, ranging from absent to severe nonspecific symptoms and may be life-threatening in patients with adrenocorticotropic hormone deficiency. The LIM homeobox gene 4 (LHX4) transcription factor regulates early embryonic development of the anterior pituitary gland. Autosomal dominant mutations in LHX4 cause congenital hypopituitarism with variable combined pituitary hormone deficiency (CPHD). We report on a neonate with unexplained heart failure and minor physical anomalies, suggesting a midline defect. She was diagnosed with complete CPHD. Cardiac function was rescued by replacement with hydrocortisone and thyroxine; hypoglycaemia stopped under growth hormone therapy. Magnetic resonance imaging revealed a dysgenetic pituitary gland suggesting an early developmental defect. Array comparative genomic hybridization showed a maternally inherited 1.5-megabase microdeletion in 1q25.2q25.3, including the LHX4 gene. Haploinsufficiency of LHX4 likely explains the predominant pituitary phenotype in the proposita and we suggest variable intrafamilial penetrance of the inherited microdeletion. To the best of our knowledge, we are the first to report on heart failure as a rare nonspecific symptom of treatable CPHD in the newborn. Variably penetrant pituitary insufficiency, including this severe and atypical presentation, can be correlated with LHX4 insufficiency and highlights the role of LHX4 for pituitary development.


Assuntos
Alelos , Aberrações Cromossômicas , Deleção Cromossômica , Cromossomos Humanos Par 1/genética , Insuficiência Cardíaca/diagnóstico , Insuficiência Cardíaca/genética , Hipopituitarismo/diagnóstico , Hipopituitarismo/genética , Proteínas com Homeodomínio LIM/genética , Malformações do Sistema Nervoso/diagnóstico , Malformações do Sistema Nervoso/genética , Fatores de Transcrição/genética , Quimioterapia Combinada , Feminino , Insuficiência Cardíaca/tratamento farmacológico , Terapia de Reposição Hormonal , Hormônio do Crescimento Humano/uso terapêutico , Humanos , Hidrocortisona/uso terapêutico , Hipopituitarismo/tratamento farmacológico , Lactente , Recém-Nascido , Imageamento por Ressonância Magnética , Malformações do Sistema Nervoso/tratamento farmacológico , Penetrância , Fenótipo , Hipófise/anormalidades , Hipófise/patologia , Tiroxina/uso terapêutico
8.
Community Dent Oral Epidemiol ; 40(3): 277-87, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22049927

RESUMO

OBJECTIVES: Previous studies have found an association between bruxism and emotional and behavioral problems in children, but reported data are inconsistent. The objective of this study was to estimate the prevalence of bruxism, and of its components clenching and grinding, and its associations with mental problems and depression. METHODS: Data from two Brazilian birth cohorts were analyzed: one from 869 children in Ribeirão Preto - RP (São Paulo), a more developed city, and the other from 805 children in São Luís - SL (Maranhão). Current bruxism - evaluated by means of a questionnaire applied to the parents/persons responsible for the children - was defined when the habit of tooth clenching during daytime and/or tooth grinding at night still persisted until the time of the assessment. Additionally, the lifetime prevalence of clenching during daytime only and grinding at night only was also evaluated. Mental health problems were investigated using the Strength and Difficulties Questionnaire (SDQ) and depression using the Children's Depression Inventory (CDI). Analyses were carried out for each city: with the SDQ subscales (emotional symptoms, conduct problems, peer problems, attention/hyperactivity disorder), with the total score (sum of the subscales), and with the CDI. These analyses were performed considering different response variables: bruxism, clenching only, and grinding only. The risks were estimated using a Poisson regression model. Statistical inferences were based on 95% confidence intervals (95% CI). RESULTS: There was a high prevalence of current bruxism: 28.7% in RP and 30.0% in SL. The prevalence of clenching was 20.3% in RP and 18.8% in SL, and grinding was found in 35.7% of the children in RP and 39.1% in SL. Multivariable analysis showed a significant association of bruxism with emotional symptoms and total SDQ score in both cities. When analyzed separately, teeth clenching was associated with emotional symptoms, peer problems, and total SDQ score; grinding was significantly associated with emotional symptoms and total SDQ score in RP and SL. Female sex appeared as a protective factor for bruxism, and for clenching and grinding in RP. Furthermore, maternal employment outside the home and white skin color of children were associated with increased prevalence of teeth clenching in SL. CONCLUSIONS: Mental health problems were associated with bruxism, with teeth clenching only and grinding at night only. No association was detected between depression and bruxism, neither clenching nor grinding. But it is necessary to be cautious regarding the inferences from some of our results.


Assuntos
Bruxismo/psicologia , Depressão/complicações , Transtornos Mentais/complicações , Adolescente , Brasil/epidemiologia , Bruxismo/epidemiologia , Bruxismo/etiologia , Criança , Pré-Escolar , Estudos de Coortes , Feminino , Humanos , Masculino , Análise Multivariada , Prevalência , Escalas de Graduação Psiquiátrica , Fatores de Risco , Fatores Sexuais , Bruxismo do Sono/etiologia , Bruxismo do Sono/psicologia , Inquéritos e Questionários
9.
Int J Dev Biol ; 55(4-5): 477-82, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21732274

RESUMO

Cancer stem cells (CSCs) or tumor initiating cells were identified and characterized as a unique subpopulation with stem cell features in many types of cancer. Current CSC studies provide novel insights regarding tumor initiation, progression, angiogenesis, resistance to therapy and interplay with the tumor micro-environment. A cancer stem cell niche has been proposed based on these findings. The niche provides the soil for CSC self-renewal and maintenance, stimulating essential signaling pathways in CSCs and leading to secretion of factors that promote angiogenesis and long term growth of CSCs. We present evidence which has emerged over the past 5 years indicating interaction of CSCs with angiogenesis in the proposed "vascular niche". Based on these findings, targeting the "cancer stem cell niche" by combining an individualized anti-CSC approach with treatment of their microenvironment may represent a novel therapeutic strategy against solid tumor systems.


Assuntos
Neoplasias/irrigação sanguínea , Neoplasias/patologia , Células-Tronco Neoplásicas/patologia , Células-Tronco Neoplásicas/fisiologia , Neovascularização Patológica/patologia , Neovascularização Patológica/fisiopatologia , Animais , Humanos , Modelos Biológicos , Neoplasias/terapia , Transdução de Sinais/fisiologia , Nicho de Células-Tronco/patologia
10.
Cancers (Basel) ; 2(3): 1629-41, 2010 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-24281178

RESUMO

Pancreatic cancer is an aggressive malignant solid tumor well-known by early metastasis, local invasion, resistance to standard chemo- and radiotherapy and poor prognosis. Increasing evidence indicates that pancreatic cancer is initiated and propagated by cancer stem cells (CSCs). Here we review the current research results regarding CSCs in pancreatic cancer and discuss the different markers identifying pancreatic CSCs. This review will focus on metastasis, microRNA regulation and anti-CSC therapy in pancreatic cancer.

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