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1.
Proc Natl Acad Sci U S A ; 118(38)2021 09 21.
Artigo em Inglês | MEDLINE | ID: mdl-34526400

RESUMO

How does the public want a COVID-19 vaccine to be allocated? We conducted a conjoint experiment asking 15,536 adults in 13 countries to evaluate 248,576 profiles of potential vaccine recipients who varied randomly on five attributes. Our sample includes diverse countries from all continents. The results suggest that in addition to giving priority to health workers and to those at high risk, the public favors giving priority to a broad range of key workers and to those with lower income. These preferences are similar across respondents of different education levels, incomes, and political ideologies, as well as across most surveyed countries. The public favored COVID-19 vaccines being allocated solely via government programs but were highly polarized in some developed countries on whether taking a vaccine should be mandatory. There is a consensus among the public on many aspects of COVID-19 vaccination, which needs to be taken into account when developing and communicating rollout strategies.


Assuntos
Vacinas contra COVID-19/administração & dosagem , COVID-19/prevenção & controle , Saúde Pública , Opinião Pública , Vacinação/psicologia , Adulto , Pessoal de Saúde , Humanos , SARS-CoV-2 , Inquéritos e Questionários
2.
Cytometry A ; 101(10): 818-834, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-34128311

RESUMO

Assays based on Förster resonance energy transfer (FRET) can be used to study many processes in cell biology. Although this is most often done with microscopy for fluorescence detection, we report two ways to measure FRET in living cells by flow cytometry. Using a conventional flow cytometer and the "3-cube method" for intensity-based calculation of FRET efficiency, we measured the enzymatic activity of specific kinases in cells expressing a genetically-encoded reporter. For both AKT and protein kinase A, the method measured kinase activity in time-course, dose-response, and kinetic assays. Using the Cytek Aurora spectral flow cytometer, which applies linear unmixing to emission measured in multiple wavelength ranges, FRET from the same reporters was measured with greater single-cell precision, in real time and in the presence of other fluorophores. Results from gene-knockout studies suggested that spectral flow cytometry might enable the sorting of cells on the basis of FRET. The methods we present provide convenient and flexible options for using FRET with flow cytometry in studies of cell biology.


Assuntos
Transferência Ressonante de Energia de Fluorescência , Proteínas Proto-Oncogênicas c-akt , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Citometria de Fluxo/métodos , Transferência Ressonante de Energia de Fluorescência/métodos , Proteínas Luminescentes/genética , Proteínas Luminescentes/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo
3.
BMC Neurosci ; 22(1): 60, 2021 10 09.
Artigo em Inglês | MEDLINE | ID: mdl-34627165

RESUMO

BACKGROUND: Autism spectrum disorder (ASD) is a complex neurodevelopmental condition characterized by persistent deficits in social communication and interaction. Common genetic variation appears to play a key role in the development of this condition. In this systematic review, we describe the relationship between genetic variations and autism. We created a gene dataset of the genes involved in the pathogenesis of autism and performed an over-representation analysis to evaluate the biological functions and molecular pathways that may explain the associations between these variants and the development of ASD. RESULTS: 177 studies and a gene set composed of 139 were included in this qualitative systematic review. Enriched pathways in the over-representation analysis using the KEGG pathway database were mostly associated with neurotransmitter receptors and their subunits. Major over-represented biological processes were social behavior, vocalization behavior, learning and memory. The enriched cellular component of the proteins encoded by the genes identified in this systematic review were the postsynaptic membrane and the cell junction. CONCLUSIONS: Among the biological processes that were examined, genes involved in synaptic integrity, neurotransmitter metabolism, and cell adhesion molecules were significantly involved in the development of autism.


Assuntos
Transtorno do Espectro Autista/genética , Predisposição Genética para Doença/genética , Aprendizagem/fisiologia , Polimorfismo Genético/genética , Testes Genéticos/métodos , Variação Genética/genética , Humanos
4.
Blood ; 129(13): 1811-1822, 2017 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-28223280

RESUMO

CD99 is a crucial regulator of the transmigration (diapedesis) of leukocytes through the blood vessel wall. Here, we report that CD99 acts at 2 different steps in the extravasation process. In agreement with previous antibody-blocking experiments, we found that CD99 gene inactivation caused neutrophil accumulation between venular endothelial cells and the basement membrane in the inflamed cremaster. Unexpectedly, we additionally found that leukocyte attachment to the luminal surface of the venular endothelium was impaired in the absence of CD99. Intravital video microscopy revealed that CD99 supported rapid chemokine-induced leukocyte arrest. Inhibition of leukocyte attachment and extravasation were both solely due to the absence of CD99 on endothelial cells, whereas CD99 on leukocytes was irrelevant. Therefore, we searched for heterophilic ligands of endothelial CD99 on neutrophils. We found that endothelial cells bind to the paired immunoglobulinlike receptors (PILRs) in a strictly CD99-dependent way. In addition, endothelial CD99 was coprecipitated with PILRs from neutrophils that adhered to endothelial cells. Furthermore, soluble CD99 carrying a transferable biotin tag could transfer this tag covalently to PILR when incubated with intact neutrophils. Binding of neutrophils under flow to a surface coated with P-selectin fragment crystallizable (Fc) and intercellular adhesion molecule 1 (ICAM-1) Fc became more shear resistant if CD99 Fc was coimmobilized. This increased shear resistance was lost if neutrophils were preincubated with anti-PILR antibodies. We concluded that endothelial CD99 promotes leukocyte attachment to endothelium in inflamed vessels by a heterophilic ligand. In addition, CD99 binds to PILRs on neutrophils, an interaction that leads to increased shear resistance of the neutrophil attachment to ICAM-1.


Assuntos
Antígeno 12E7/metabolismo , Receptores Imunológicos/metabolismo , Animais , Adesão Celular , Movimento Celular , Endotélio Vascular , Molécula 1 de Adesão Intercelular/metabolismo , Leucócitos/citologia , Camundongos , Neutrófilos/metabolismo , Ligação Proteica
5.
J Immunol ; 196(3): 1327-37, 2016 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-26729812

RESUMO

Human CD14(++)CD16(-) and CD14(+/lo)CD16(+) monocyte subsets comprise 85 and 15% of blood monocytes, respectively, and are thought to represent distinct stages in the monocyte differentiation pathway. However, the differentiation fates of both monocyte subsets along the macrophage (Mϕ) lineage have not yet been elucidated. We have now evaluated the potential of CD14(++) CD16(-) and CD16(+) monocytes to differentiate and to be primed toward pro- or anti-inflammatory Mϕs upon culture with GM-CSF or M-CSF, respectively (subsequently referred to as GM14, M14, GM16, or M16). Whereas GM16 and GM14 were phenotypic and functionally analogous, M16 displayed a more proinflammatory profile than did M14. Transcriptomic analyses evidenced that genes associated with M-CSF-driven Mϕ differentiation (including FOLR2, IL10, IGF1, and SERPINB2) are underrepresented in M16 with respect to M14. The preferential proinflammatory skewing of M16 relative to M14 was found to be mediated by the secretion of activin A and the low levels of IL-10 produced by M16. In fact, activin A receptor blockade during the M-CSF-driven differentiation of CD16(+) monocytes, or addition of IL-10-containing M14-conditioned medium, significantly enhanced their expression of anti-inflammatory-associated molecules while impairing their acquisition of proinflammatory-related markers. Thus, we propose that M-CSF drives CD14(++)CD16- monocyte differentiation into bona fide anti-inflammatory Mϕs in a self-autonomous manner, whereas M-CSF-treated CD16(+) monocytes generate Mϕs with a skewed proinflammatory profile by virtue of their high activin A expression unless additional anti-inflammatory stimuli such as IL-10 are provided.


Assuntos
Ativinas/biossíntese , Diferenciação Celular/imunologia , Interleucina-10/biossíntese , Macrófagos/citologia , Monócitos/imunologia , Ativinas/imunologia , Western Blotting , Separação Celular , Citometria de Fluxo , Imunofluorescência , Humanos , Inflamação/imunologia , Interleucina-10/imunologia , Macrófagos/imunologia , Monócitos/citologia , Análise de Sequência com Séries de Oligonucleotídeos , Reação em Cadeia da Polimerase em Tempo Real , Receptores de IgG/imunologia
6.
Cancer Res ; 81(23): 6029-6043, 2021 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-34625423

RESUMO

The family of PIM serine/threonine kinases includes three highly conserved oncogenes, PIM1, PIM2, and PIM3, which regulate multiple prosurvival pathways and cooperate with other oncogenes such as MYC. Recent genomic CRISPR-Cas9 screens further highlighted oncogenic functions of PIMs in diffuse large B-cell lymphoma (DLBCL) cells, justifying the development of small-molecule PIM inhibitors and therapeutic targeting of PIM kinases in lymphomas. However, detailed consequences of PIM inhibition in DLBCL remain undefined. Using chemical and genetic PIM blockade, we comprehensively characterized PIM kinase-associated prosurvival functions in DLBCL and the mechanisms of PIM inhibition-induced toxicity. Treatment of DLBCL cells with SEL24/MEN1703, a pan-PIM inhibitor in clinical development, decreased BAD phosphorylation and cap-dependent protein translation, reduced MCL1 expression, and induced apoptosis. PIM kinases were tightly coexpressed with MYC in diagnostic DLBCL biopsies, and PIM inhibition in cell lines and patient-derived primary lymphoma cells decreased MYC levels as well as expression of multiple MYC-dependent genes, including PLK1. Chemical and genetic PIM inhibition upregulated surface CD20 levels in an MYC-dependent fashion. Consistently, MEN1703 and other clinically available pan-PIM inhibitors synergized with the anti-CD20 monoclonal antibody rituximab in vitro, increasing complement-dependent cytotoxicity and antibody-mediated phagocytosis. Combined treatment with PIM inhibitor and rituximab suppressed tumor growth in lymphoma xenografts more efficiently than either drug alone. Taken together, these results show that targeting PIM in DLBCL exhibits pleiotropic effects that combine direct cytotoxicity with potentiated susceptibility to anti-CD20 antibodies, justifying further clinical development of such combinatorial strategies. SIGNIFICANCE: These findings demonstrate that inhibition of PIM induces DLBCL cell death via MYC-dependent and -independent mechanisms and enhances the therapeutic response to anti-CD20 antibodies by increasing CD20 expression.


Assuntos
Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Linfoma Difuso de Grandes Células B/tratamento farmacológico , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas c-myc/genética , Proteínas Proto-Oncogênicas c-pim-1/antagonistas & inibidores , Rituximab/farmacologia , Animais , Antígenos CD20 , Antineoplásicos Imunológicos/farmacologia , Apoptose , Proliferação de Células , Feminino , Humanos , Linfoma Difuso de Grandes Células B/genética , Linfoma Difuso de Grandes Células B/metabolismo , Linfoma Difuso de Grandes Células B/patologia , Camundongos , Camundongos SCID , Fosforilação , Proteínas Proto-Oncogênicas c-myc/metabolismo , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
7.
Hum Mutat ; 30(11): E956-73, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19634183

RESUMO

Mutational analysis of the GNPTAB gene was performed in 46 apparently unrelated patients with mucolipidosis IIalpha/beta or IIIalpha/beta, characterized by the mistargeting of multiple lysosomal enzymes as a consequence of a UDP-GlcNAc-1-phosphotransferase defect. The GNPTAB mutational spectrum comprised 25 distinct mutant alleles, 22 of which were novel, including 3 nonsense mutations (p.Q314X, p.R375X, p.Q507X), 5 missense mutations (p.I403T, p.C442Y, p.C461G, p.Q926P, p.L1001P), 6 microduplications (c.749dupA, c.857dupA, c.1191_1194dupGCTG, c.1206dupT, c.1331dupG, c.2220_2221dupGA) and 8 microdeletions (c.755_759delCCTCT, c.1399delG, c.1959_1962delTAGT, c.1965delC, c.2550_2554delGAAAA, c.3443_3446delTTTG, c.3487_3490delACAG, c.3523_3529delATGTTCC). All micro-duplications/deletions were predicted to result in the premature termination of translation. A novel exonic SNP (c.303G>A; E101E) was identified which is predicted to create an SFRS1 (SF2/ASF) binding site that may be of potential functional/clinical relevance. This study of mutations in the GNPTAB gene, the largest yet reported, extends our knowledge of the mutational heterogeneity evident in MLIIalpha/beta/MLIIIalpha/beta.


Assuntos
Mucolipidoses/genética , Mutação , Transferases (Outros Grupos de Fosfato Substituídos)/genética , Adolescente , Adulto , Animais , Células COS , Criança , Pré-Escolar , Chlorocebus aethiops , Códon sem Sentido , Análise Mutacional de DNA , Estudos de Associação Genética , Genótipo , Humanos , Lactente , Mutação de Sentido Incorreto , Deleção de Sequência
8.
Elife ; 82019 08 06.
Artigo em Inglês | MEDLINE | ID: mdl-31385804

RESUMO

Arrest of rapidly flowing neutrophils in venules relies on capturing through selectins and chemokine-induced integrin activation. Despite a long-established concept, we show here that gene inactivation of activating paired immunoglobulin-like receptor (PILR)-ß1 nearly halved the efficiency of neutrophil arrest in venules of the mouse cremaster muscle. We found that this receptor binds to CD99, an interaction which relies on flow-induced shear forces and boosts chemokine-induced ß2-integrin-activation, leading to neutrophil attachment to endothelium. Upon arrest, binding of PILR-ß1 to CD99 ceases, shifting the signaling balance towards inhibitory PILR-α. This enables integrin deactivation and supports cell migration. Thus, flow-driven shear forces guide sequential signaling of first activating PILR-ß1 followed by inhibitory PILR-α to prompt neutrophil arrest and then transmigration. This doubles the efficiency of selectin-chemokine driven neutrophil arrest by PILR-ß1 and then supports transition to migration by PILR-α.


Assuntos
Antígeno 12E7/metabolismo , Células Sanguíneas , Neutrófilos/fisiologia , Receptores Imunológicos/metabolismo , Migração Transendotelial e Transepitelial , Animais , Antígenos CD18/metabolismo , Camundongos , Ligação Proteica
9.
Clin Cancer Res ; 25(14): 4455-4465, 2019 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-31004002

RESUMO

PURPOSE: Mantle cell lymphoma (MCL) is an aggressive subtype of B-cell non-Hodgkin lymphomas characterized by (over)expression of BCL2. A BCL2-targeting drug, venetoclax, has promising anticancer activity in MCL. We analyzed molecular mechanisms of venetoclax resistance in MCL cells and tested strategies to overcome it. EXPERIMENTAL DESIGN: We confirmed key roles of proapoptotic proteins BIM and NOXA in mediating venetoclax-induced cell death in MCL. Both BIM and NOXA are, however, differentially expressed in cell lines compared with primary cells. First, NOXA protein is significantly overexpressed in most MCL cell lines. Second, deletions of BIM gene harbored by three commonly used MCL cell lines (JEKO-1, MINO, and Z138) were not found by array comparative genomic hybridization using a validation set of 24 primary MCL samples. RESULTS: We demonstrated that MCL1 and NOXA play important roles in mediating resistance to venetoclax. Consequently, we tested an experimental treatment strategy based on cotargeting BCL2 with venetoclax and MCL1 with a highly specific small-molecule MCL1 inhibitor S63845. The combination of venetoclax and S63845 demonstrated synthetic lethality in vivo on a panel of five patient-derived xenografts established from patients with relapsed MCL with adverse cytogenetics. CONCLUSIONS: Our data strongly support investigation of venetoclax in combination with S63845 as an innovative treatment strategy for chemoresistant MCL patients with adverse cytogenetics in the clinical grounds.


Assuntos
Compostos Bicíclicos Heterocíclicos com Pontes/farmacologia , Sinergismo Farmacológico , Linfoma de Célula do Manto/tratamento farmacológico , Proteína de Sequência 1 de Leucemia de Células Mieloides/antagonistas & inibidores , Recidiva Local de Neoplasia/tratamento farmacológico , Proteínas Proto-Oncogênicas c-bcl-2/antagonistas & inibidores , Pirimidinas/farmacologia , Sulfonamidas/farmacologia , Tiofenos/farmacologia , Animais , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Resistencia a Medicamentos Antineoplásicos , Feminino , Humanos , Linfoma de Célula do Manto/metabolismo , Linfoma de Célula do Manto/patologia , Camundongos , Camundongos Endogâmicos NOD , Proteína de Sequência 1 de Leucemia de Células Mieloides/metabolismo , Recidiva Local de Neoplasia/metabolismo , Recidiva Local de Neoplasia/patologia , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
10.
Neuromuscul Disord ; 17(1): 16-22, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17056254

RESUMO

Pompe disease is an autosomal recessive disorder caused by a deficiency in 1,4-alpha-glucosidase (EC.3.2.1.3), the enzyme required to hydrolyze lysosomal glycogen to glucose. While previous studies have focused on Pompe patients from Europe, the United States, and Taiwan, we have analyzed a group of South American Pompe patients to better understand the molecular basis of their disease. From 14 Argentinean patients diagnosed with either infantile or late-onset disease, we identified 14 distinct mutations in the acid alpha-glucosidase (GAA) gene including nine novel variants (c.236_246del, c.377G>A, c.1099T>C, c.1397T>G, c.1755-1G>A, c.1802C>G, c.1978C>T, c.2281delGinsAT, and c.2608C>T). Three different families displayed the c.377G>A allelic variant, suggesting a higher frequency among a subset of Argentineans. Comparison of patients with similar or identical variations in the GAA gene highlights the phenotypic diversity of late-onset disease and supports a role for other genetic and environmental factors in disease presentation.


Assuntos
Doença de Depósito de Glicogênio Tipo II/epidemiologia , Doença de Depósito de Glicogênio Tipo II/genética , Mutação , alfa-Glucosidases/genética , Adolescente , Adulto , Idade de Início , Argentina/epidemiologia , Criança , Pré-Escolar , Análise Mutacional de DNA , Feminino , Genótipo , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , alfa-Glucosidases/metabolismo
11.
J Leukoc Biol ; 101(5): 1133-1142, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28122813

RESUMO

Neutrophil extravasation is a critical step of the innate immune system's response to inflammation. This multistep process is tightly regulated by adhesion and signaling molecules in the endothelium and neutrophils. Activation of the ß2 integrin LFA-1 is critical for adhesion of leukocytes to postcapillary venules. This step requires coordinated activation of signaling pathways in chemokine-stimulated neutrophils, including GTPase activation and cytoskeletal remodeling, leading to conformational changes in LFA-1. Hematopoietic cell-specific lyn substrate 1 (HS1) is a cortactin-related and leukocyte-specific actin-binding protein (ABP) that regulates several processes in various immune cells. It has been shown in vitro that HS1 is important for neutrophil chemotaxis and transendothelial migration of NK cells, but its role in neutrophil extravasation in vivo has not been investigated yet. Intravital microscopy of CXCL1-stimulated cremaster venules revealed an increased rolling velocity and reduced neutrophil adhesion and transmigration in HS1 knockout (KO) mice. CXCL1-induced rapid neutrophil arrest in vivo and adhesion under flow conditions in vitro were also reduced significantly. Whereas random motility of neutrophils was unaffected, chemotaxis toward a CXCL1 gradient was reduced in the absence of HS1. Further analysis of the underlying mechanisms demonstrated that HS1 controls CXCL1-induced activation of the small GTPases Ras-related C3 botulinum toxin substrate 1 (Rac1) and Ras-related protein 1 (Rap1), thus supporting LFA-1-mediated neutrophil adhesion. Importantly, with the use of Rac1 KO neutrophils, we could show that Rac1 acts upstream of Rap1. Our results establish HS1 as an important regulator of proper Rac1 and Rap1 activation and neutrophil extravasation.


Assuntos
Fator Estimulador de Colônias de Granulócitos/imunologia , Antígeno-1 Associado à Função Linfocitária/imunologia , Neuropeptídeos/imunologia , Neutrófilos/imunologia , Peritonite/imunologia , Proteínas rac1 de Ligação ao GTP/imunologia , Proteínas rap1 de Ligação ao GTP/imunologia , Músculos Abdominais/irrigação sanguínea , Músculos Abdominais/citologia , Músculos Abdominais/imunologia , Animais , Adesão Celular/efeitos dos fármacos , Quimiocina CXCL1/genética , Quimiocina CXCL1/imunologia , Quimiocina CXCL1/farmacologia , Quimiotaxia/efeitos dos fármacos , Fator Estimulador de Colônias de Granulócitos/deficiência , Fator Estimulador de Colônias de Granulócitos/genética , Imunidade Inata , Microscopia Intravital , Antígeno-1 Associado à Função Linfocitária/genética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Neuropeptídeos/genética , Infiltração de Neutrófilos/efeitos dos fármacos , Neutrófilos/efeitos dos fármacos , Neutrófilos/patologia , Peritonite/genética , Peritonite/patologia , Cultura Primária de Células , Proteínas rac1 de Ligação ao GTP/genética , Proteínas rap1 de Ligação ao GTP/genética
12.
Clin Chim Acta ; 317(1-2): 191-7, 2002 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11814475

RESUMO

BACKGROUND: Gaucher disease (GD) and Niemann-Pick (NP) disease are caused by deficient activity of the lysosomal enzymes acid beta-D-glucosidase (ABG) and acid sphingomyelinase (ASM), respectively. For diagnosis, these enzymes are usually measured in the extracts of leukocytes or cultured fibroblasts. Chitotriosidase (CTE), a chitinolytic enzyme, is markedly increased in the plasma of Gaucher patients. We describe methods for the assay of acid beta-D-glucosidase, acid sphingomyelinase, chitotriosidase, and alpha-N-acetyl-galactosaminidase (NAGA) as a control enzyme in blood spots that were dried onto filter paper. METHODS: To tubes containing a 3 mm-diameter blood spot, we added elution liquid and substrate solution. After incubation at 37 degrees C, the amount of hydrolyzed product was compared with a calibrator to allow the quantification of enzyme activity. We examined 80 healthy controls, 54 Gaucher patients, 8 Niemann-Pick patients, 27 obligate carriers, and the newborn-screening cards (NSC) from a case of Gaucher and a case of Niemann-Pick disease. RESULTS AND CONCLUSION: The described methodology is useful to identify Gaucher and Niemann-Pick patients and controls, using samples that are sufficiently stable to be transported to the testing laboratory by mail. The diagnosis of both diseases on a newborn-screening card was clearly established. The newborn-screening card has been added to the biological materials that allow the identification of patients with Gaucher and Niemann-Pick diseases.


Assuntos
Doença de Gaucher/diagnóstico , Glucosilceramidase/sangue , Hexosaminidases/sangue , Doenças de Niemann-Pick/diagnóstico , Esfingomielina Fosfodiesterase/sangue , Adolescente , Adulto , Bioensaio/métodos , Coleta de Amostras Sanguíneas/métodos , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Triagem Neonatal/métodos , Estudos Retrospectivos , alfa-N-Acetilgalactosaminidase
13.
Clin Chim Acta ; 318(1-2): 133-7, 2002 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11880123

RESUMO

BACKGROUND: Tay-Sachs disease (TSD), Sandhoff disease (SD) and variants are caused by deficient activity of the lysosomal enzymes hexosaminidase A (HA) and total hexosaminidase (TH) (hexosaminidase A plus B), respectively. For diagnosis, these enzymes are usually measured in plasma or extracts of leukocytes. We describe methods for the assay of hexosaminidase A and total hexosaminidase activities in dried blood spots (DBSs) on filter paper. MATERIALS AND METHODS: We studied 163 healthy controls, 9 Tay-Sachs patients, 4 Sandhoff patients, 18 obligate carriers and the newborn-screening cards from two patients with Tay-Sachs and one patient with Sandhoff disease. To tubes containing a 3-mm-diameter blood spot, we added elution liquid and substrate solution. After incubation at 37 degrees C, the amount of hydrolyzed product was compared with a calibrator to allow the quantification of enzyme activity. RESULTS AND CONCLUSIONS: The described methodology is useful to distinguish patients with Tay-Sachs disease or Sandhoff disease from carriers and controls using samples that are sufficiently stable to be transported to the testing laboratory by mail. The diagnosis of both diseases from a newborn-screening card (NSC) was clearly demonstrated, even after storage for up to 38 months at room temperature. The newborn-screening card has been added to the biological materials that allow the identification of patients with Tay-Sachs disease and Sandhoff disease.


Assuntos
Triagem Neonatal/métodos , Doença de Sandhoff/enzimologia , Doença de Tay-Sachs/enzimologia , Adulto , Sangue Fetal/enzimologia , Testes Hematológicos , Hexosaminidase A , Humanos , Recém-Nascido , Valores de Referência , Estudos Retrospectivos , Doença de Sandhoff/sangue , Doença de Tay-Sachs/sangue , beta-N-Acetil-Hexosaminidases/sangue
14.
Clin Chim Acta ; 347(1-2): 97-102, 2004 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-15313146

RESUMO

BACKGROUND: Glycogen storage disease II is characterized by a deficiency of the lysosomal enzyme acid alpha-glucosidase. Currently, glycogen storage disease II is diagnosed by demonstrating the virtual absence or a marked reduction of acid alpha-glucosidase activity in muscle biopsies, cultured fibroblasts, or purified lymphocytes. Early diagnosis and treatment of glycogen storage disease II are considered to be critical for maximum efficacy of the enzyme replacement therapies that are in development. However, these existing diagnostic methods are not suited for newborn screening. We developed an assay useful for newborn screening for glycogen storage disease II. METHODS: A series of three enzyme assays to measure the alpha-glucosidase activities in dried blood spots on filter paper was developed. The measurement of acid alpha-glucosidase activity with minimal interference by other alpha-glucosidases was accomplished using maltose as an inhibitor. The method was used on samples from glycogen storage disease II patients, obligate heterozygotes, and healthy controls. RESULTS: Glycogen storage disease II patients were distinguished from carriers and healthy controls using the series of enzyme assays. CONCLUSIONS: We developed a simple and noninvasive screening method for glycogen storage disease II. The method could be incorporated into newborn screening.


Assuntos
Doença de Depósito de Glicogênio Tipo II/sangue , Doença de Depósito de Glicogênio Tipo II/diagnóstico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Soluções Tampão , Criança , Pré-Escolar , Diagnóstico Diferencial , Feminino , Filtração , Glucana 1,4-alfa-Glucosidase/antagonistas & inibidores , Doença de Depósito de Glicogênio Tipo II/enzimologia , Inibidores de Glicosídeo Hidrolases , Humanos , Concentração de Íons de Hidrogênio , Indicadores e Reagentes , Lactente , Recém-Nascido , Masculino , Maltose/química , Maltose/farmacologia , Pessoa de Meia-Idade , Triagem Neonatal , Papel , Manejo de Espécimes
15.
Arch Argent Pediatr ; 112(3): 258-62, 2014 Jun.
Artigo em Espanhol | MEDLINE | ID: mdl-24862809

RESUMO

Mucopolysaccharidosis VI (MPS VI) is a lysosomal storage disease associated with a deficiency or absence of arylsulfatase B leading to the abnormal accumulation of dermatan sulfate. MPS VI shows a wide spectrum of symptoms from slowly to rapidly progressing forms. The characteristic spectrum includes skeletal displasia, coarse facies, cardiomyopathy, pulmonary complications and spinal compression. Diagnosis generally requires measurement ofurinary glycosaminoglycans and arylsulfatase B enzyme activity in dried blood spot, leukocytes or cultured fibroblasts. Enzyme replacement therapy (ERT) with galsulfase is now widely available providing improvement in skeletal performance and stabilization in pulmonary and cardiac functioning. Spinal involvement does not respond to ERT when is present, surgical decompression should be indicated early. Prognosis is variable depending on the age of onset and age at initiation of ERT.


Assuntos
Terapia de Reposição de Enzimas , Mucopolissacaridose VI/diagnóstico , Mucopolissacaridose VI/tratamento farmacológico , N-Acetilgalactosamina-4-Sulfatase/uso terapêutico , Criança , Progressão da Doença , Humanos
16.
Gene ; 499(2): 262-5, 2012 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-22441121

RESUMO

Tay-Sachs disease (TSD) is a recessively inherited disorder caused by the deficient activity of hexosaminidase A due to mutations in the HEXA gene. Up to date there is no information regarding the molecular genetics of TSD in Argentinean patients. In the present study we have studied 17 Argentinean families affected by TSD, including 20 patients with the acute infantile form and 3 with the sub-acute form. Overall, we identified 14 different mutations accounting for 100% of the studied alleles. Eight mutations were novel: 5 were single base changes leading to drastic residue changes or truncated proteins, 2 were small deletions and one was an intronic mutation that may cause a splicing defect. Although the spectrum of mutations was highly heterogeneous, a high frequency of the c.459+5G>A mutation, previously described in different populations was found among the studied cohort. Haplotype analysis suggested that in these families the c.459+5G>A mutation might have arisen by a single mutational event.


Assuntos
Hexosaminidase A/genética , Mutação , Doença de Tay-Sachs/genética , Criança , Estudos de Coortes , Feminino , Humanos , Lactente , Masculino
18.
Arch. argent. pediatr ; 112(3): 258-262, jun. 2014. ilus
Artigo em Espanhol | LILACS, BINACIS | ID: biblio-1159607

RESUMO

La mucopolisacaridosis de tipo VI (MPS VI) es una enfermedad de almacenamiento lisosomal resultante del déficit o ausencia de la arilsulfatasa B, que conduce a una acumulación patológica de dermatán-sulfato. Presenta un amplio espectro de síntomas, que van desde formas lentas hasta rápidamente progresivas. Los síntomas característicos son el compromiso esquelético, facies tosca, cardiopatía y compresión medular cervical. El diagnóstico se realiza por la determinación de glucosaminoglucanos en la orina y de la actividad enzimática en una gota de sangre seca, leucocitos o cultivo de fibroblastos. Actualmente, la terapia de reemplazo enzimático (TRE) con galsulfasa ha mostrado mejorar el compromiso esquelético y estabilizar la función respiratoria y cardíaca. El compromiso medular no suele responder a la TRE cuando ya se encuentra presente, por lo que la descompresión quirúrgica debe indicarse en forma temprana. El pronóstico varía en función del fenotipo y de la edad de inicio del tratamiento


Mucopolysaccharidosis VI (MPS VI) is a lysosomal storage disease associated with a deficiency or absence of arylsulfatase B leading to the abnormal accumulation of dermatan sulfate. MPS VI shows a wide spectrum of symptoms from slowly to rapidly progressing forms. The characteristic spectrum includes skeletal displasia, coarse facies, cardiomyopathy, pulmonary complications and spinal compression. Diagnosis generally requires measurement ofurinary glycosaminoglycans and arylsulfatase B enzyme activity in dried blood spot, leukocytes or cultured fibroblasts. Enzyme replacement therapy (ERT) with galsulfase is now widely available providing improvement in skeletal performance and stabilization in pulmonary and cardiac functioning. Spinal involvement does not respond to ERT when is present, surgical decompression should be indicated early. Prognosis is variable depending on the age of onset and age at initiation of ERT.


Assuntos
Humanos , Criança , Mucopolissacaridose VI/diagnóstico , Mucopolissacaridose VI/tratamento farmacológico , N-Acetilgalactosamina-4-Sulfatase/uso terapêutico , Terapia de Reposição de Enzimas , Progressão da Doença
19.
J. inborn errors metab. screen ; 2: e130003, 2014. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1090856

RESUMO

Abstract Introduction: Fabry disease (FD) is a lysosomal storage disorder associated with marked cerebrovascular involvement. Conventional magnetic resonance imaging (MRI) shows different abnormalities, like white matter lesions that may already be present at an early stage in the disease. Aim: To present observations from a series of brain MRIs performed among a cohort of patients with FD and the relationship of imaging abnormalities with the presence of cardiovascular risk factors (CVRFs). Methods: A total of 70 patients with FD (43 women) were enrolled. The cardiac, renal, ophthalmic, and peripheral nerve functioning was assessed. The MRI evaluation included assessment for evidence of ischemia, microbleeds, pulvinar sign, Arnold-Chiari type 1 malformation, and vertebrobasilar dolichoectasia (VBD). The presence or absence of CVRFs was examined for all patients. Results: Renal involvement was found in 60%, cardiac compromise in 30%, cornea verticillata in 91.4%, and acroparesthesias in 87.1% of patients. Brain MRI analysis found evidence of cerebral ischemic injury in 25.9% of men and 30.2% of women. Vertebrobasilar dolichoectasia was observed in imaging from 55.5% of men and 34.8% of women. The logistic regression analysis adjusted for cardiovascular risks factors, using ischemia or VBD as a dependent variable, showed no statistically significant results. Discussion: Our results have demonstrated cerebrovascular involvement before the third decade in many patients with FD. This study is further evidence confirming that women are not just carriers of FD and should be followed clinically and evaluated comprehensively to monitor for disease burden and progression. Although silent brain ischemias in MRI should be included as a key feature for the diagnoses of FD, VBD is an earlier and frequent sign.

20.
Clin Chim Acta ; 402(1-2): 38-41, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19111682

RESUMO

BACKGROUND: Lysosomal storage disorders (LSDs) are pathologies caused by the deficit of lysosomal enzymes; late diagnosis may render therapeutic programs less effective. As early, pre-symptomatic detection could change the natural history of the disease, we are setting up rapid microassays using dried blood spots (DBS) on filter paper. Here we report alpha-glucosidase and beta-galactosidase assays. METHODS: Enzymatic activities were evaluated on DBS from five different groups of subjects including healthy controls and patients affected with an LSD. A 260-day monitoring of DBS preservation at five different temperatures and a comparison of the enzymatic activities measured in DBS obtained from a single (sDBS) or a double (dDBS) blood drop were performed as well. RESULTS: Both assays could clearly distinguish the affected patients from the other subjects analyzed. Storage of DBS at 4 degrees C and below allowed a longer preservation of the enzymatic activities. No significant differences were detected between sDBS and dDBS. CONCLUSIONS: DBS can be used for non-invasive, easy, inexpensive lysosomal enzyme assays. Reliability of assays on DBS needs to be checked using a control enzyme such as beta-galactosidase. DBS can be still reliably analyzed even if generated incidentally by two overlapped drops.


Assuntos
Análise Química do Sangue/métodos , Doenças por Armazenamento dos Lisossomos/diagnóstico , alfa-Glucosidases/sangue , beta-Galactosidase/sangue , Adulto , Humanos , Recém-Nascido , Pessoa de Meia-Idade
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