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1.
Immunity ; 37(1): 48-59, 2012 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-22770884

RESUMO

γδ T cells are an important innate source of interleukin-17 (IL-17). In contrast to T helper 17 (Th17) cell differentiation, which occurs in the periphery, IL-17-producing γδ T cells (γδT17 cells) are probably committed during thymic development. To study when γδT17 cells arise during ontogeny, we used TcrdH2BeGFP reporter mice to monitor T cell receptor (TCR) rearrangement and IL-17 production in the embryonic thymus. We observed that several populations such as innate lymphoid cells and early T cell precursors were able to produce IL-17 prior to (and thus independent of) TCR recombination. γδT17 cells were absent after transplantation of IL-17-sufficient bone marrow into mice lacking both Il17a and Il17f. Also, γδT17 cells were not generated after genetic restoration of defective Rag1 function in adult mice. Together, these data suggested that these cells developed exclusively before birth and subsequently persisted in adult mice as self-renewing, long-lived cells.


Assuntos
Interleucina-17/biossíntese , Receptores de Antígenos de Linfócitos T gama-delta/imunologia , Receptores de Antígenos de Linfócitos T gama-delta/metabolismo , Subpopulações de Linfócitos T/imunologia , Subpopulações de Linfócitos T/metabolismo , Animais , Medula Óssea/metabolismo , Quimerismo , Homeostase/imunologia , Imunidade Inata , Interleucina-17/deficiência , Interleucina-17/genética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Receptores de Antígenos de Linfócitos T alfa-beta/imunologia , Receptores de Antígenos de Linfócitos T alfa-beta/metabolismo , Receptores CCR6/metabolismo , Timócitos/citologia , Timócitos/imunologia , Timócitos/metabolismo , Timo/embriologia , Timo/metabolismo , Membro 7 da Superfamília de Receptores de Fatores de Necrose Tumoral/metabolismo
2.
J Med Internet Res ; 23(9): e30161, 2021 09 17.
Artigo em Inglês | MEDLINE | ID: mdl-34375298

RESUMO

BACKGROUND: The COVID-19 global health crisis has led to an exponential surge in published scientific literature. In an attempt to tackle the pandemic, extremely large COVID-19-related corpora are being created, sometimes with inaccurate information, which is no longer at scale of human analyses. OBJECTIVE: In the context of searching for scientific evidence in the deluge of COVID-19-related literature, we present an information retrieval methodology for effective identification of relevant sources to answer biomedical queries posed using natural language. METHODS: Our multistage retrieval methodology combines probabilistic weighting models and reranking algorithms based on deep neural architectures to boost the ranking of relevant documents. Similarity of COVID-19 queries is compared to documents, and a series of postprocessing methods is applied to the initial ranking list to improve the match between the query and the biomedical information source and boost the position of relevant documents. RESULTS: The methodology was evaluated in the context of the TREC-COVID challenge, achieving competitive results with the top-ranking teams participating in the competition. Particularly, the combination of bag-of-words and deep neural language models significantly outperformed an Okapi Best Match 25-based baseline, retrieving on average, 83% of relevant documents in the top 20. CONCLUSIONS: These results indicate that multistage retrieval supported by deep learning could enhance identification of literature for COVID-19-related questions posed using natural language.


Assuntos
COVID-19 , Algoritmos , Humanos , Armazenamento e Recuperação da Informação , Idioma , SARS-CoV-2
3.
Ann Hum Genet ; 83(6): 418-425, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31090060

RESUMO

OBJECTIVE: Preeclampsia (PE) is a life-threatening complication of pregnancy that accounts for 12% of all maternal deaths worldwide. The aim of this study is to investigate the relationships between the polymorphisms of angiotensinogen (AGT) gene and preeclampsia. MATERIAL AND METHODS: In this study, 240 unrelated preeclampsia patients and 178 normotensive women were examined. Genomic DNA was extracted then we assessed M235T(C/T) and A-6G polymorphisms of the AGT gene. Genotyping of M235T and A-6G polymorphisms were performed using SSP-PCR and MS-PCR, respectively. RESULTS: A significant protective association was observed between A-6G G allele, A-6G A/G heterozygote genotype (OR = 0.6, p = 0.007 and OR = 0.6, p = 0.04) against PE. Furthermore, it was shown that two copies of A-6G A allele would increase PE risk (OR: 0.62, p = 0.04). Our results did not show a significant association for M235T polymorphism and PE. However, the combinations of A-6G A/A genotype and M235T T/C genotype (OR = 0.4, p = 0.02) and also A-6G A/G genotype and M235T T/C genotype (OR = 0.5, p = 0.04) in controls represented a significant protective association against PE. CONCLUSION: According to the existence of significant correlation between two candidate polymorphisms, A-6G and M235T polymorphisms, with PE disease in our study, they may be considered as valuable factors in susceptibility to PE disease in Iranian women.


Assuntos
Alelos , Substituição de Aminoácidos , Angiotensinogênio/genética , Predisposição Genética para Doença , Polimorfismo de Nucleotídeo Único , Pré-Eclâmpsia/genética , Adolescente , Adulto , Estudos de Casos e Controles , Feminino , Estudos de Associação Genética , Genótipo , Humanos , Padrões de Herança , Irã (Geográfico)/epidemiologia , Razão de Chances , Pré-Eclâmpsia/epidemiologia , Gravidez , Medição de Risco , Fatores de Risco , Adulto Jovem
4.
Immunol Cell Biol ; 92(5): 409-16, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24418818

RESUMO

T-cell receptor α (TCRα) chain rearrangement is not constrained by allelic exclusion and thus αß T cells frequently have rearranged both alleles of this locus. Thereby, stepwise secondary rearrangements of both TCRα loci further increase the odds for generation of an α-chain that can be positively selected in combination with a pre-existing TCRß chain. Previous studies estimated that approximately 2-12% of murine and human αß T cells still carry one TCRα locus in germline configuration, which must comprise a partially or even fully rearranged TCRδ locus. However, these estimates are based on a relatively small amount of individual αß T-cell clones and αß T-cell hybridomas analyzed to date. To address this issue more accurately, we made use of a mouse model, in which a fluorescent reporter protein is introduced into the constant region of the TCRδ locus. In this TcrdH2BeGFP system, fluorescence emanating from retained TCRδ loci enabled us to quantify monoallelically rearranged αß T cells on a single-cell basis. Via fluorescence-activated cell sorting analysis, we determined the frequency of monoallelic TCRα rearrangements to be 1.7% in both peripheral CD4(+) and CD8(+) αß T cells. Furthermore, we found a skewed 5' Jα gene utilization of the rearranged TCRα allele in T cells with monoallelic TCRα rearrangements. This is in line with previous descriptions of a tight interallelic positional coincidence of Jα gene segments used on both TCRα alleles. Finally, analysis of T cells from transgenic mice harboring only one functional TCRα locus implied the existence of very rare unusual translocation or episomal reintegration events of formerly excised TCRδ loci.


Assuntos
Alelos , Rearranjo Gênico do Linfócito T , Receptores de Antígenos de Linfócitos T alfa-beta/genética , Receptores de Antígenos de Linfócitos T alfa-beta/metabolismo , Subpopulações de Linfócitos T/metabolismo , Animais , Expressão Gênica , Frequência do Gene , Genes Reporter , Loci Gênicos , Camundongos , Camundongos Transgênicos
5.
Neuro Oncol ; 25(4): 662-673, 2023 04 06.
Artigo em Inglês | MEDLINE | ID: mdl-36124685

RESUMO

BACKGROUND: Adult-type diffuse gliomas, CNS WHO grade 4 are the most aggressive primary brain tumors and represent a particular challenge for therapeutic intervention. METHODS: In a single-center retrospective study of matched pairs of initial and post-therapeutic glioma cases with a recurrence period greater than 1 year, we performed whole exome sequencing combined with mRNA and microRNA expression profiling to identify processes that are altered in recurrent gliomas. RESULTS: Mutational analysis of recurrent gliomas revealed early branching evolution in 75% of the patients. High plasticity was confirmed at the mRNA and miRNA levels. SBS1 signature was reduced and SBS11 was elevated, demonstrating the effect of alkylating agent therapy on the mutational landscape. There was no evidence for secondary genomic alterations driving therapy resistance. ALK7/ACVR1C and LTBP1 were upregulated, whereas LEFTY2 was downregulated, pointing towards enhanced Tumor Growth Factor ß (TGF-ß) signaling in recurrent gliomas. Consistently, altered microRNA expression profiles pointed towards enhanced Nuclear Factor Kappa B and Wnt signaling that, cooperatively with TGF-ß, induces epithelial to mesenchymal transition (EMT), migration, and stemness. TGF-ß-induced expression of pro-apoptotic proteins and repression of antiapoptotic proteins were uncoupled in the recurrent tumor. CONCLUSIONS: Our results suggest an important role of TGF-ß signaling in recurrent gliomas. This may have clinical implications since TGF-ß inhibitors have entered clinical phase studies and may potentially be used in combination therapy to interfere with chemoradiation resistance. Recurrent gliomas show high incidence of early branching evolution. High tumor plasticity is confirmed at the level of microRNA and mRNA expression profiles.


Assuntos
Neoplasias Encefálicas , Glioma , MicroRNAs , Humanos , Adulto , Regulação para Cima , Transição Epitelial-Mesenquimal/genética , Estudos Retrospectivos , Glioma/patologia , Fator de Crescimento Transformador beta/genética , Fator de Crescimento Transformador beta/metabolismo , MicroRNAs/genética , Recidiva , RNA Mensageiro/metabolismo , Neoplasias Encefálicas/metabolismo , Linhagem Celular Tumoral , Receptores de Ativinas Tipo I/genética , Receptores de Ativinas Tipo I/metabolismo
6.
Cancers (Basel) ; 14(21)2022 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-36358647

RESUMO

Serine/Threonine protein phosphatase 2A (PP2A) is a heterotrimeric (or occasionally, heterodimeric) phosphatase with pleiotropic functions and ubiquitous expression. Despite the fact that they all contribute to protein dephosphorylation, multiple PP2A complexes exist which differ considerably by their subcellular localization and their substrate specificity, suggesting diverse PP2A functions. PP2A complex formation is tightly regulated by means of gene expression regulation by transcription factors, microRNAs, and post-translational modifications. Furthermore, a constant competition between PP2A regulatory subunits is taking place dynamically and depending on the spatiotemporal circumstance; many of the integral subunits can outcompete the rest, subjecting them to proteolysis. PP2A modulation is especially important in the context of brain tumors due to its ability to modulate distinct glioma-promoting signal transduction pathways, such as PI3K/Akt, Wnt, Ras, NF-κb, etc. Furthermore, PP2A is also implicated in DNA repair and survival pathways that are activated upon treatment of glioma cells with chemo-radiation. Depending on the cancer cell type, preclinical studies have shown some promise in utilising PP2A activator or PP2A inhibitors to overcome therapy resistance. This review has a special focus on "glioblastoma, IDH wild-type" (GBM) tumors, for which the therapy options have limited efficacy, and tumor relapse is inevitable.

7.
Eur J Cancer ; 159: 227-236, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34781171

RESUMO

BACKGROUND: Brain metastases present a significant complication in lung cancer with an unmet therapeutic need. METHODS: In this single-centre, retrospective study, we genotyped a clinico-pathologically well-annotated cohort of consecutively resected brain metastases of lung adenocarcinomas and paired primary tumours, diagnosed from 2000 to 2015, using the Ion Torrent Oncomine Comprehensive Cancer Panel v3. RESULTS: Among 444 consecutive brain metastases, 210 (49%) originated from lung cancer. Analysis was successful in 111 samples, including 54 pairs of brain metastasis and primary tumour. Most driver alterations were preserved in brain metastases. Private alterations exclusive to primary tumours, brain metastases or both sites (intersecting cases) were present in 22%, 26% and 26% of cases, respectively. Seven percent had no shared mutations. KRAS mutations were more frequent in primary tumours metastasised to the brain (32/55, 58%) compared to TCGA (33%, p < 0.005) and own data from routine diagnostics, independent from clinical or pathological characteristics. Fourteen cases showed alterations in the EGFR signalling pathway including additional KRAS alterations that were private to brain metastases. KRAS G12C was detected most frequently (26% of patients) and KRAS G12C and G13C variants were significantly enriched in brain metastases. Synchronous and metachronous cases had a similar mutation profile. CONCLUSIONS: Our results suggest an important role of KRAS alterations in the pathobiology of brain metastases from lung adenocarcinomas. This has direct therapeutic implications as inhibitors selectively targeting KRAS G12C are entering the clinics.


Assuntos
Adenocarcinoma/genética , Adenocarcinoma/secundário , Neoplasias Encefálicas/secundário , Neoplasias Pulmonares/genética , Proteínas Proto-Oncogênicas p21(ras)/genética , Idoso , Feminino , Humanos , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Mutação , Estudos Retrospectivos
8.
J Diabetes Metab Disord ; 20(2): 1743-1765, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34222055

RESUMO

The novel coronavirus, which began spreading from China Wuhan and gradually spreaded to most countries, led to the announcement by the World Health Organization on March 11, 2020, as a new pandemic. The most important point presented by the World Health Organization about this disease is to better understand the risk factors that exacerbate the course of the disease and worsen its prognosis. Due to the high majority of cardio metabolic risk factors like obesity, hypertension, diabetes, and dyslipidemia among the population over 60 years old and higher, these cardio metabolic risk factors along with the age of these people could worsen the prognosis of the coronavirus disease of 2019 (COVID-19) and its mortality. In this study, we aimed to review the articles from the beginning of the pandemic on the impression of cardio metabolic risk factors on COVID-19 and the effectiveness of COVID-19 on how to manage these diseases. All the factors studied in this article, including hypertension, diabetes mellitus, dyslipidemia, and obesity exacerbate the course of Covid-19 disease by different mechanisms, and the inflammatory process caused by coronavirus can also create a vicious cycle in controlling these diseases for patients.

9.
Horm Mol Biol Clin Investig ; 41(4)2020 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-33581015

RESUMO

OBJECTIVES: The main purpose of this study was to compare the effects of two regimens of metformin and insulin therapy on postpartum oral glucose tolerance test (OGTT) results in pregnant women with gestational diabetes mellitus (GDM). METHODS: In this single-blind randomized clinical trial (RCT), a total number of 60 pregnant women meeting the inclusion criteria were assigned to two groups with a randomized block design (RBD): insulin therapy (IT) group (30 patients) and metformin therapy (MT) group (30 patients). At baseline, the data were comprised of prenatal maternal age, gestational age, GDM diagnosis, and maternal weight/height. During the postpartum period, 5-cc blood samples were taken from the pregnant women concerned to analyze their fasting blood sugar (FBS) levels. Then, the patients were asked to come back four days and six weeks later after delivery to check the OGTT results. At six weeks postpartum, in addition to OGTT, the glycated hemoglobin (HbA1C) test was performed for all mothers. Finally, six weeks after delivery, these mothers were evaluated with regard to weight loss and body mass index (BMI). RESULTS: Six weeks postpartum, the maternal weight and BMI significantly decreased in the MT group compared with the IT one, while there was no significant difference between both groups at baseline. On the fourth day, the OGTT results in the MT group were significantly lower in comparison with those in the IT group (p=0.012). At sixth weeks postpartum, the OGTT results were comparably lower in the MT group than those reported for the IT one; however, such a difference was not statistically significant (p=0.087). CONCLUSIONS: According to the study results, metformin could be an effective and safe treatment for pregnant women suffering from GDM instead of insulin therapy.


Assuntos
Diabetes Gestacional/sangue , Diabetes Gestacional/tratamento farmacológico , Insulina/uso terapêutico , Metformina/uso terapêutico , Glicemia , Índice de Massa Corporal , Diabetes Gestacional/diagnóstico , Feminino , Teste de Tolerância a Glucose , Humanos , Insulina/administração & dosagem , Metformina/administração & dosagem , Período Pós-Parto , Gravidez , Resultado do Tratamento
10.
Biomolecules ; 9(10)2019 09 21.
Artigo em Inglês | MEDLINE | ID: mdl-31546665

RESUMO

Colorectal cancer (CRC) is the third most commonly diagnosed cancer worldwide, representing 13% of all cancers. The role of epigenetics in cancer diagnosis and prognosis is well established. MicroRNAs in particular influence numerous cancer associated processes including apoptosis, proliferation, differentiation, cell-cycle controls, migration/invasion and metabolism. MiRNAs-137 and 342 are exon- and intron-embedded, respectively, acting as tumour-suppressive microRNA via hypermethylation events. Levels of miRNAs 137 and 342 have been investigated here as potential prognostic markers for colorectal cancer patients. The methylation status of miRNA-137 and miRNA-342 was evaluated using methylation-specific (MSP) polymerase chain reaction (PCR) on freshly frozen tissue derived from 51 polyps, 8 tumours and 14 normal colon mucosa specimens. Methylation status of miRNA-137 and miRNA-342 was significantly higher in tumour lesions compared to normal adjacent mucosa. Surprisingly, the methylation frequency of miR-342 (76.3%) among colorectal cancer patients was significantly higher compared to miR-137 (18.6%). Furthermore, normal tissues, adjacent to the lesions (N-Cs), displayed no observable methylation for miRNA-137, whereas 27.2% of these N-Cs showed miRNA-342 hypermethylation. MiRNA-137 hypermethylation was significantly higher in male patients and miR-342 hypermethylation correlated with patient age. Methylation status of miRNA-137 and miRNA-342 has both diagnostic and prognostic value in CRC prediction and prevention.


Assuntos
Neoplasias Colorretais/genética , Metilação de DNA , MicroRNAs/genética , Adolescente , Adulto , Fatores Etários , Biomarcadores Tumorais/genética , Neoplasias Colorretais/diagnóstico , Ilhas de CpG , Epigênese Genética , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Regiões Promotoras Genéticas , Fatores Sexuais , Adulto Jovem
11.
Eur J Obstet Gynecol Reprod Biol ; 193: 75-8, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26254854

RESUMO

OBJECTIVE: Preeclampsia is a syndrome that affects 5% of all pregnancies, producing substantial maternal and prenatal morbidity and mortality. Several studies have reported that cytokine genes are associated with the persistence of preeclampsia or the severity of the disease. The aim of this study is to investigate the relationships between the polymorphisms of interleukin-1 alpha-889 (IL-1A) gene and preeclampsia. METHOD: Genomic DNA was extracted from the peripheral blood of 305 patients with preeclampsia and 325 normal controls from Sayyad Shirazi Hospital of Golestan University. Then subjected to SSP-PCR amplification. STATA software and the chi square test were used for statistic calculations. RESULTS: The frequencies of IL-1A -889 genotypes C/C, T/T and C/T in preeclampsia cases were 34.8%, 8.2%, 57% and in controls were 20.9%, 7.6% and 71.3% respectively. There was a significant 1.5 fold excess frequency in genotype C/C in cases (CI=1.44-3.07, OR=2.1, P=0.0001). There was a significant difference in the frequencies of alleles or genotypes in IL-1A promoter regions between patients with preeclampsia and the control group. Turkomans showed the highest frequency of the C allele and Sistanies had the lowest frequency of the C allele in preeclampsia compared to control groups (CI=1.5-3.9, OR=2.48, P=0.0001). CONCLUSION: Our findings suggest that the IL-1A-899C/C genotype and C allele are associated with susceptibility to preeclampsia.


Assuntos
Interleucina-1alfa/genética , Pré-Eclâmpsia/genética , Adolescente , Adulto , Estudos de Casos e Controles , Feminino , Frequência do Gene , Genótipo , Humanos , Irã (Geográfico) , Polimorfismo de Nucleotídeo Único , Pré-Eclâmpsia/etnologia , Gravidez , Regiões Promotoras Genéticas , Adulto Jovem
12.
Nat Commun ; 6: 6477, 2015 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-25765849

RESUMO

Here we investigate the TCR repertoire of mouse Vγ4(+) γδ T cells in correlation with their developmental origin and homeostasis. By deep sequencing we identify a high frequency of straight Vδ5Dδ2Jδ1 germline rearrangements without P- and N-nucleotides within the otherwise highly diverse Trd repertoire of Vγ4(+) cells. This sequence is infrequent in CCR6(-)CD27(+) cells, but abundant among CCR6(+)CD27(-) γδ T cells. Using an inducible Rag1 knock-in mouse model, we show that γδ T cells generated in the adult thymus rarely contain this germline-rearranged Vδ5Dδ2Jδ1 sequence, confirming its fetal origin. Single-cell analysis and deep sequencing of the Trg locus reveal a dominant CDR3 junctional motif that completes the TCR repertoire of invariant Vγ4(+)Vδ5(+) cells. In conclusion, this study identifies an innate subset of fetal thymus-derived γδ T cells with an invariant Vγ4(+)Vδ5(+) TCR that is restricted to the CCR6(+)CD27(-) subset of γδ T cells.


Assuntos
Receptores de Antígenos de Linfócitos T gama-delta/genética , Receptores CCR6/metabolismo , Subpopulações de Linfócitos T/citologia , Membro 7 da Superfamília de Receptores de Fatores de Necrose Tumoral/metabolismo , Motivos de Aminoácidos , Sequência de Aminoácidos , Animais , Movimento Celular , Mutação em Linhagem Germinativa , Proteínas de Fluorescência Verde/metabolismo , Imunidade Inata , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Dados de Sequência Molecular , Fenótipo , Reação em Cadeia da Polimerase , Análise de Sequência de DNA , Análise de Célula Única , Timo/metabolismo , Distribuição Tecidual
13.
Asian Pac J Cancer Prev ; 13(9): 4517-20, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23167371

RESUMO

INTRODUCTION: Northeastern Iran is known as a high risk area of upper gastrointestinal cancers. Recent reports have suggested a declining trend for these cancers as well as an increase in the incidence of other malignancies including breast cancer. Our present aim was to describe the epidemiological pattern of breast cancer in this region during 2004-2009. METHODS: All new cancer cases from public and private diagnostic and therapeutic centers of Golestan province were registered. A structured questionnaire was prepared and used based on the standards of the International Association of Cancer Registries. The international classification of diseases for oncology was considered for coding. Age standardized incidence rates (ASR) of breast cancer were calculated. RESULTS: A total of 11,038 new cancer cases were registered during 2004-2009, of which, 1,101 (10%) were females with breast cancer. The median age of the breast cancer patients was 46 years. The ASR for breast cancer was 28 per 100,000 person-years. We found an unusual rapid increase in breast cancer rate at the age of 25 years. The ASR of breast cancer was significantly lower in females from Turkmen ethnicity and those from rural areas (P value <0.01). CONCLUSION: Our study showed high rate of breast cancer in Golestan province of Iran. We found an unusual peak of breast cancer in young women. So, the age of starting screening programs may need to be revised in this area. The rate of breast cancer was significantly lower in women from Turkmen ethnicity. Further studies are warranted to clarify the role of important determinants, especially regarding the ethnic disparity, on breast cancer in this region.


Assuntos
Neoplasias da Mama/epidemiologia , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/etnologia , Feminino , Humanos , Incidência , Classificação Internacional de Doenças , Irã (Geográfico)/epidemiologia , Pessoa de Meia-Idade , Distribuição de Poisson , População Rural/estatística & dados numéricos , Inquéritos e Questionários , Adulto Jovem
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