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1.
Artigo em Inglês | MEDLINE | ID: mdl-38334049

RESUMO

BACKGROUND AND OBJECTIVE: With the global population on the rise, edible insects are considered a potential solution to food security, although concerns about risks such as anaphylaxis exist. METHODS: 2,014 participants underwent testing with the Allergy Explorer-ALEX-2 including extracts of three novel foods: Acheta Domesticus (Ad), Locusta migratoria (Lm), and Tenebrio molitor (Tm). The IgE-mediated sensitization status was investigated in participants who had never knowingly consumed these insects. Data was recorded using an electronic database. RESULTS: 195 individuals (9.7% of all participants) were sensitized to insects. Tropomyosin was co-recognized by 34%, and 18.5% were positive for arginine kinases. Reactivity to Sarcoplasmic-CB, Troponin-C, Paramyosin, or Myosin-light-chain was found in less than 5% of the population, whereas 108 individuals (55.4%) did not show any reactivity to invertebrate panallergens. Additionally, 33 individuals (16.9%) exhibited monosensitization exclusively to insects. Multivariate analysis revealed an inverse association between arachnid reactivity and sensitization to insect allergens, while Mollusca, Blattoidea, and tropomyosin reactivity displayed a direct relationship. Furthermore, Myosin-light-chain reactivity correlated with Ad and Lm, and Troponin-C with Ad and Tm sensitization. CONCLUSION: Edible insect extract IgE sensitization was observed in individuals without prior exposure to such foods. Mites showed a low likelihood of being primary sensitizers due to their inverse association with insect reactivity. Conversely, the direct association of insect sensitization with mollusk and cockroach extract reactivity suggests their potential as primary sensitizers in these participants. Tropomyosin consistently exhibited a positive association with reactivity to all studied insects, supporting its role as a primary sensitizer.

2.
Neurobiol Dis ; 190: 106388, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38141856

RESUMO

BACKGROUND: MLC1 is a membrane protein highly expressed in brain perivascular astrocytes and whose mutations account for the rare leukodystrophy (LD) megalencephalic leukoencephalopathy with subcortical cysts disease (MLC). MLC is characterized by macrocephaly, brain edema and cysts, myelin vacuolation and astrocyte swelling which cause cognitive and motor dysfunctions and epilepsy. In cultured astrocytes, lack of functional MLC1 disturbs cell volume regulation by affecting anion channel (VRAC) currents and the consequent regulatory volume decrease (RVD) occurring in response to osmotic changes. Moreover, MLC1 represses intracellular signaling molecules (EGFR, ERK1/2, NF-kB) inducing astrocyte activation and swelling following brain insults. Nevertheless, to date, MLC1 proper function and MLC molecular pathogenesis are still elusive. We recently reported that in astrocytes MLC1 phosphorylation by the Ca2+/Calmodulin-dependent kinase II (CaMKII) in response to intracellular Ca2+ release potentiates MLC1 activation of VRAC. These results highlighted the importance of Ca2+ signaling in the regulation of MLC1 functions, prompting us to further investigate the relationships between intracellular Ca2+ and MLC1 properties. METHODS: We used U251 astrocytoma cells stably expressing wild-type (WT) or mutated MLC1, primary mouse astrocytes and mouse brain tissue, and applied biochemistry, molecular biology, video imaging and electrophysiology techniques. RESULTS: We revealed that WT but not mutant MLC1 oligomerization and trafficking to the astrocyte plasma membrane is favored by Ca2+ release from endoplasmic reticulum (ER) but not by capacitive Ca2+ entry in response to ER depletion. We also clarified the molecular events underlining MLC1 response to cytoplasmic Ca2+ increase, demonstrating that, following Ca2+ release, MLC1 binds the Ca2+ effector protein calmodulin (CaM) at the carboxyl terminal where a CaM binding sequence was identified. Using a CaM inhibitor and generating U251 cells expressing MLC1 with CaM binding site mutations, we found that CaM regulates MLC1 assembly, trafficking and function, being RVD and MLC-linked signaling molecules abnormally regulated in these latter cells. CONCLUSION: Overall, we qualified MLC1 as a Ca2+ sensitive protein involved in the control of volume changes in response to ER Ca2+ release and astrocyte activation. These findings provide new insights for the comprehension of the molecular mechanisms responsible for the myelin degeneration occurring in MLC and other LD where astrocytes have a primary role in the pathological process.


Assuntos
Doenças Desmielinizantes , Megalencefalia , Camundongos , Animais , Astrócitos/metabolismo , Cálcio/metabolismo , Calmodulina/metabolismo , Doenças Desmielinizantes/patologia , Mutação/genética , Retículo Endoplasmático/metabolismo , Megalencefalia/metabolismo
3.
Artigo em Inglês | MEDLINE | ID: mdl-37712443

RESUMO

Summary: Background. LTP allergy is often a challenge for clinicians. We evaluated a multiplex diagnostic approach with diverse cofactors to stratify LTP syndrome risk. Methods. Of the 1,831 participants screened with 'Allergy Explorer-ALEX-2', 426 had reactions to at least one LTP. Data was gathered and recorded via an electronic database. Results. Reactivity to peach Pru p 3 was found in 77% of individuals with LTP allergy. Higher levels of specific IgE and concurrent sensitization to more than 5 molecules (50% of all LTP-sensitised participants, 62% of symptomatic cases) were significantly associated with an increased risk of severe reactions (p = 0.001). Several cofactors, either alone or in combination, also influenced patients' clinical outcomes. Some cofactors increased the risk of severe reactions, such as mono reactivity to LTP in 44.6% of cases (p = 0.001), FDEIA in 10.8% of patients (p = 0.001), and FDNIH in 11.5% (p = 0.005). On the other hand, reactivity to PR10 (24.2%; p = 0.001), profilin hypersensitivity (10.3%; p = 0.001), and/or atopic dermatitis (16.7%; p = 0.001) had a mitigating effect on symptom severity. Conclusions. Clinical severity of LTP syndrome is associated with an expanded IgE repertoire in terms of the number of LTP components recognized and increased IgE levels in individual molecules. Ara h 9, Cor a 8, and Mal d 3 showed the strongest association with clinical severity. In addition, several cofactors may either exacerbate (FDEIA, FDHIH, and LTP monoreactivity) or ameliorate (atopic dermatitis and co-sensitization to profilin and/or PR10) individual patient outcomes. These factors may be utilized for the daily clinical management of LTP syndrome.

4.
Int J Immunopathol Pharmacol ; 25(2): 503-11, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22697083

RESUMO

Orofacial granulomatosis (OFG) is a clinicopathologic entity describing oral lesions with noncaseating granulomas including a spectrum of diseases such as the Melkersson-Rosenthal syndrome. The involvement of abnormal T-cell responses has been suggested in the pathogenesis of OFG although few and contrasting data are currently available on this issue. In a patient with OFG, we observed virtually complete CD4 and CD8 T-cell receptor (TCR) ß-chain variable region (BV) repertoires at the lesion level and in circulation. However, oligoclonal profiles were found in CD4 and, to a greater extent, in CD8 subsets. These findings were seen in association with a massive peripheral T-cell activation, decreased naive T cells, reduced thymic output, altered cytokine production, and increased apoptosis. Our data, pointing to a random influx of T cells at the site of inflammation, argue against the hypothesis of a main allergen acting at the level of oral mucosa. The profound dysregulation of the peripheral T-cell compartment suggests that OFG should be regarded as a systemic disorder with localized manifestations.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Lábio/imunologia , Ativação Linfocitária/imunologia , Síndrome de Melkersson-Rosenthal/imunologia , Receptores de Antígenos de Linfócitos T alfa-beta/biossíntese , Receptores de Antígenos de Linfócitos T alfa-beta/imunologia , Subpopulações de Linfócitos T/imunologia , Apoptose , Biomarcadores/metabolismo , Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD4-Positivos/patologia , Linfócitos T CD8-Positivos/metabolismo , Linfócitos T CD8-Positivos/patologia , Células Cultivadas , Citocinas/metabolismo , Citometria de Fluxo , Humanos , Imunofenotipagem , Lábio/patologia , Masculino , Síndrome de Melkersson-Rosenthal/diagnóstico , Subpopulações de Linfócitos T/metabolismo , Subpopulações de Linfócitos T/patologia , Adulto Jovem
5.
Clin Exp Immunol ; 167(1): 120-8, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22132891

RESUMO

Immune dysregulation, polyendocrinopathy, enteropathy, X-linked (IPEX) is a rare syndrome due to a mutation in the forkhead box protein 3 gene (FOXP3) leading to an impaired regulatory T cell (T(reg) ) activity associated both with skewed T helper type 2 (Th2) response and autoreactive phenomena. The purpose of this study was to describe a combined proteomics and genomics approach to comprehensively evaluate clinical and immunological phenotypes of patients affected by IPEX. T cell receptor (TCR)-Vß repertoire and peripheral blood lymphocytes phenotype from three brothers affected by IPEX were studied by flow cytometry. Specific immunoglobulin (Ig)E were evaluated by means of an allergenic molecules microarray [immuno solid-phase allergen chip (ISAC)]. Total RNA was extracted and hybridized to Affymetrix oligonucleotide arrays to obtain quantitative gene-expression levels. No FOXP3 protein was detectable within CD127(-) CD25(high) CD4(+) T cells from peripheral blood. A T cell-naive phenotype (CD62L(+) CD45R0(-)) associated with a reduction of both CD26 and CD7 expression and a TCR-Vß 8 and 22 family expansions were found. B lymphocytes were mainly CD5(+) (B1) cells expressing a naive phenotype (tcl1(+) CD27(-)). The three IPEX patients had severe food allergy and specific IgE reactivity to cow's milk allergens, a hen's egg allergen and a wheat allergen. Gene expression profile analysis revealed a dysregulation associated mainly with Th1/Th2 pathways. The multiplexing evaluation reported in this study represents a comprehensive approach in the assessment of genetic conditions affecting the immune system such as the IPEX syndrome, paving the way for the development of diagnostic tools to improve the standard clinical and immunological profiling of the disease.


Assuntos
Doenças do Sistema Endócrino/genética , Hipersensibilidade Alimentar/genética , Fatores de Transcrição Forkhead/deficiência , Genes Ligados ao Cromossomo X , Doenças Genéticas Ligadas ao Cromossomo X/genética , Genômica/métodos , Síndromes de Imunodeficiência/genética , Proteômica/métodos , Adolescente , Adulto , Doenças do Sistema Endócrino/sangue , Doenças do Sistema Endócrino/imunologia , Hipersensibilidade Alimentar/sangue , Hipersensibilidade Alimentar/imunologia , Fatores de Transcrição Forkhead/genética , Perfilação da Expressão Gênica , Doenças Genéticas Ligadas ao Cromossomo X/sangue , Doenças Genéticas Ligadas ao Cromossomo X/imunologia , Humanos , Imunoglobulina E/imunologia , Síndromes de Imunodeficiência/sangue , Imunofenotipagem , Linfoma Difuso de Grandes Células B/genética , Linfoma Difuso de Grandes Células B/patologia , Masculino , Análise de Sequência com Séries de Oligonucleotídeos , Receptores de Antígenos de Linfócitos T alfa-beta/genética , Análise de Sequência de DNA , Subpopulações de Linfócitos T/imunologia , Neoplasias Tonsilares/genética , Neoplasias Tonsilares/patologia , Adulto Jovem
6.
Cell Death Dis ; 2: e151, 2011 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-21525938

RESUMO

Sézary syndrome (SS) is an incurable leukemic variant of cutaneous T-cell lymphoma and its pathogenesis is still unknown. Diagnosis/prognosis may strongly ameliorate the management of SS individuals. Here, we profiled the expression of 470 microRNAs (miRNAs) in a cohort of 22 SS patients, and we identified 45 miRNAs differentially expressed between SS and controls. Using predictive analysis, a list of 19 miRNAs, including miR-21, miR-214, miR-486, miR-18a, miR-342, miR-31 and let-7 members were also found. Moreover, we defined a signature of 14 miRNAs including again miR-21, potentially able to discriminate patients with unfavorable and favorable outcome. We validated our data for miR-21, miR-214 and miR-486 by qRT-PCR, including an additional set of array-independent SS cases. In addition, we also provide an in vitro evidence for a contribution of miR-214, miR-486 and miR-21 to apoptotic resistance of CTCL cell line.


Assuntos
Biomarcadores Tumorais/genética , Sobrevivência Celular/genética , Perfilação da Expressão Gênica , MicroRNAs/genética , Síndrome de Sézary/genética , Neoplasias Cutâneas/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Apoptose/genética , Biomarcadores Tumorais/metabolismo , Linhagem Celular Tumoral , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , MicroRNAs/metabolismo , Pessoa de Meia-Idade , Nucleossomos/metabolismo , Síndrome de Sézary/metabolismo , Síndrome de Sézary/mortalidade , Neoplasias Cutâneas/metabolismo , Neoplasias Cutâneas/mortalidade , Linfócitos T/metabolismo , Regulação para Cima
7.
Br J Dermatol ; 162(3): 611-8, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19906071

RESUMO

BACKGROUND: Accurate assessment of the somatic mutational status of clonal immunoglobulin variable region (IgV) genes is relevant in elucidating tumour cell origin in B-cell lymphoma; virgin B cells bear unmutated IgV genes, while germinal centre and postfollicular B cells carry mutated IgV genes. Furthermore, biases in the IgV repertoire and distribution pattern of somatic mutations indicate a possible antigen role in the pathogenesis of B-cell malignancies. OBJECTIVES: This work investigates the cellular origin and antigenic selection in primary cutaneous B-cell lymphoma (PCBCL). METHODS: We analysed the nucleotide sequence of clonal IgV heavy-chain gene (IgVH) rearrangements in 51 cases of PCBCL (25 follicle centre, 19 marginal zone and seven diffuse large B-cell lymphoma, leg-type) and compared IgVH sequences with their closest germline segment in the GenBank database. Molecular data were then correlated with histopathological features. RESULTS: We showed that all but one of the 51 IgVH sequences analysed exhibited extensive somatic hypermutations. The detected mutation rate ranged from 1.6% to 21%, with a median rate of 9.8% and was independent of PCBCL histotype. Calculation of antigen-selection pressure showed that 39% of the mutated IgVH genes displayed a number of replacement mutations and silent mutations in a pattern consistent with antigenic selection. Furthermore, two segments, VH1-69 (12%) and VH4-59 (14%), were preferentially used in our case series. CONCLUSIONS: Data indicate that neoplastic B cells of PBCBL have experienced germinal centre reaction and also suggest that the involvement of IgVH genes is not entirely random in PCBCL and that common antigen epitopes could be pathologically relevant in cutaneous lymphomagenesis.


Assuntos
Rearranjo Gênico do Linfócito B/genética , Genes de Imunoglobulinas/genética , Região Variável de Imunoglobulina/genética , Linfoma de Células B/genética , Neoplasias Cutâneas/genética , Hipermutação Somática de Imunoglobulina/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Análise de Variância , Feminino , Rearranjo Gênico do Linfócito B/imunologia , Humanos , Região Variável de Imunoglobulina/imunologia , Linfoma de Células B/imunologia , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Análise de Sequência de DNA , Neoplasias Cutâneas/imunologia , Hipermutação Somática de Imunoglobulina/imunologia
8.
Clin Exp Immunol ; 132(2): 323-31, 2003 May.
Artigo em Inglês | MEDLINE | ID: mdl-12699424

RESUMO

Chromosome 22q11.2 deletion (del22q11.2) syndrome (DiGeorge syndrome/velocardiofacial syndrome) is a common syndrome typically consisting of congenital heart disease, hypoparathyroidism, developmental delay and immunodeficiency. Although a broad range of immunologic defects have been described in these patients, limited information is currently available on the diversity of the T-cell receptor (TCR) variable beta (BV) chain repertoire. The TCRBV repertoires of nine patients with del22q11.2 syndrome were determined by flow cytometry, fragment size analysis of the third complementarity determining region (CDR3 spectratyping) and sequencing of V(D)J regions. The rate of thymic output and the phenotype and function of peripheral T cells were also studied. Expanded TCRBV families were detected by flow cytometry in both CD4+ and CD8+ T cells. A decreased diversity of TCR repertoires was also demonstrated by CDR3 spectratyping, showing altered CDR3 profiles in the majority of TCRBV families investigated. The oligoclonal nature of abnormal peaks detected by CDR3 spectratyping was confirmed by the sequence analysis of the V(D)J regions. Thymic output, evaluated by measuring TCR rearrangement excision circles (TRECs), was significantly decreased in comparison with age-matched controls. Finally, a significant up-regulation in the percentage, but not in the absolute count, of activated CD4+ T cells (CD95+, CCR5+, HLA-DR+), IFN-gamma - and IL-2-expressing T cells was detected. These findings suggest that the diversity of CD4 and CD8 TCRBV repertoires is decreased in patients with del22q11.2 syndrome, possibly as a result of either impaired thymic function and/or increased T-cell activation.


Assuntos
Cromossomos Humanos Par 22 , Síndrome de DiGeorge/imunologia , Receptores de Antígenos de Linfócitos T , Subpopulações de Linfócitos T/imunologia , Timo/imunologia , Adolescente , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Estudos de Casos e Controles , Criança , Pré-Escolar , Feminino , Citometria de Fluxo , Deleção de Genes , Rearranjo Gênico da Cadeia beta dos Receptores de Antígenos dos Linfócitos T , Humanos , Região Variável de Imunoglobulina , Imunofenotipagem , Hibridização in Situ Fluorescente , Ativação Linfocitária , Masculino , Complexo Receptor-CD3 de Antígeno de Linfócitos T
9.
Oncogene ; 19(9): 1191-5, 2000 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-10713707

RESUMO

The phosphatase 2A (PP2A) is one of the major cellular serine-threonine phosphatases. It was recently shown that the gene encoding for the beta isoform of its subunit A, PPP2R1B, is altered in human lung and colorectal carcinomas, suggesting a role in human tumorigenesis. Here, we report the detection of mutations in breast, lung carcinomas and melanomas in the genes of both alpha (PPP2R1A) and beta isoforms. Mutations affecting PPP2R1B were found in four breast carcinomas, while mutations in PPP2R1A were found in carcinomas of the breast and of the lung and in one melanoma. Most of the mutations affecting PPP2R1B were exons deletions, suggesting abnormal splicing. These splicing abnormalities were detected in tumor samples in the absence of the normal splicing product, and were not found in several normal controls. In one case, a homozygous deletion present in tumor DNA, and not in the matched normal control was demonstrated. Mutations affecting the PPP2R1A gene were nucleotide substitutions changing highly conserved amino acids and one frame-shift. Although the frequency of alterations is low, the inclusion of both isoforms of subunit A in the genes mutated in human cancer and the addition of breast cancer to the list of neoplasms in which PPP2R1B is altered, strengthen the potential role of PP2A in human tumorogenesis.


Assuntos
Neoplasias da Mama/enzimologia , Neoplasias Pulmonares/enzimologia , Melanoma/enzimologia , Mutação , Fosfoproteínas Fosfatases/genética , Isoformas de Proteínas/genética , Substituição de Aminoácidos/genética , Sequência de Bases , Neoplasias da Mama/genética , Humanos , Neoplasias Pulmonares/genética , Melanoma/genética , Dados de Sequência Molecular , Fosfoproteínas Fosfatases/metabolismo , Reação em Cadeia da Polimerase , Polimorfismo Genético , Polimorfismo Conformacional de Fita Simples , Isoformas de Proteínas/metabolismo , Proteína Fosfatase 2 , RNA Neoplásico/genética , Deleção de Sequência , Células Tumorais Cultivadas
10.
Genomics ; 52(3): 358-62, 1998 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-9790754

RESUMO

Two distinct regions of loss of heterozygosity (LOH) in breast carcinomas were previously identified at chromosome 11q23. With the aim of identifying a tumor suppressor gene, we undertook the isolation and characterization of genes within LOH region 2, defined between loci D11S1345 and D11S1316, which spans an area of about 1 Mb. Here, we describe the cloning and characterization of a new gene, ZNF202. The gene, which spans a genomic area of approximately 10 kb, is almost exclusively expressed in testis as a 4-kb mRNA. The predicted amino acid sequence of the protein product revealed significant homologies with zinc finger proteins, indicating that the ANF202 protein may function as a transcription factor. The presence of multiple CK2 and PKC phosphorylation sites suggests that its activity may be regulated by phosphorylation. The gene is also expressed in breast carcinoma cell lines. However, mutation analysis of 39 breast cancer samples revealed no evidence of mutations, indicating that ZNF202 is unlikely to be involved in the pathogenesis of this neoplasm. Nevertheless, a role for ZNF202 in the tumorigenic process of other tissues cannot be excluded.


Assuntos
Proteínas de Transporte/genética , Cromossomos Humanos Par 11/genética , Clonagem Molecular , Fatores de Transcrição/genética , Sequência de Aminoácidos , Éxons/genética , Humanos , Íntrons/genética , Perda de Heterozigosidade/genética , Masculino , Dados de Sequência Molecular , Proteínas de Neoplasias/genética , Fosforilação , RNA Mensageiro/genética , Proteínas Repressoras , Análise de Sequência de DNA , Testículo
11.
Biochimie ; 73(12): 1465-72, 1991 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-1725258

RESUMO

Several features of translation and ribosome structure in extremely thermophilic, sulfur-dependent archaebacteria are described, including: i) a peculiar mechanism of transfer RNA-mediated 70S ribosome formation from free subunits; ii) poly(U)translation by hybrid ribosomes composed by one archaebacterial and one eucaryotic subunit; iii) ribosome assembly and homologous and heterologous RNA/protein recognition.


Assuntos
Biossíntese de Proteínas , RNA Ribossômico/metabolismo , Ribossomos/metabolismo , Sulfolobus/genética , Temperatura Alta , Concentração de Íons de Hidrogênio , RNA Bacteriano/metabolismo , Leveduras/metabolismo
12.
J Biol Chem ; 266(10): 6195-200, 1991 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-1901059

RESUMO

Studies of ribosome structure in thermophilic archaebacteria may provide valuable information on (i) the mechanisms involved in the stabilization of nucleic acid-protein complexes at high temperatures and (ii) the degree of evolutionary conservation of the ribosomal components in the primary kingdoms of cell descent. In this work we investigate certain aspects of RNA/protein interaction within the large ribosomal subunits of the extremely thermophilic archaebacterium Sulfolobus solfataricus. The ribosomal proteins involved in the early reactions leading to in vitro particle assembly have been identified; it is shown that they can interact with the RNA in a temperature-independent fashion, forming a thermally stable "core" particle that can subsequently be converted into complete 50 S ribosomes. Among the protein components of the core particle, those capable of independently binding to 23 and 5 S RNA species have also been identified. Finally, we show that the early assembly proteins of Sulfolobus large ribosomal subunits are able to interact cooperatively with 23 S RNAs from other archaebacteria or from eubacteria, thereby suggesting that RNA/protein recognition sites are largely conserved within prokaryotic ribosomes. By contrast, no specific binding of the archaebacterial proteins to eukaryotic RNA could be demonstrated.


Assuntos
Archaea/metabolismo , RNA Ribossômico 23S/metabolismo , RNA Ribossômico 5S/metabolismo , Proteínas Ribossômicas/metabolismo , Northern Blotting , Eletroforese em Gel de Poliacrilamida , Temperatura Alta , Hibridização de Ácido Nucleico , Especificidade por Substrato
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