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1.
Eur Ann Allergy Clin Immunol ; 56(1): 17-25, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36927838

RESUMO

Summary: Background. International guidelines suggested skin tests with Polyethylene-glycol (PEG) and polysorbate 80 (PS-80), to investigate a possible hypersensitivity to these excipients either to identify subjects at risk of developing allergic reactions to Covid-19 vaccines, or in patients with suspected IgE mediated hypersensitivity reactions (HR) to the Covid-19 vaccine. The main purpose of this study was to investigate the prevalence of PEG and PS sensitization in patients with a clinical history of HR to drugs containing PEG/PS and in patients with a suspected Covid-19 vaccine immediate HR. Methods. This was a multicenter retrospective study conducted by allergists belonging to 20 Italian medical centers. Skin testing was performed in 531 patients with either a clinical history of suspected hypersensitivity reaction (HR) to drugs containing PEG and/or PS-80 (group 1:362 patient) or a suspected HR to Covid-19 vaccines (group 2: 169 patient), as suggested by the AAIITO/SIAAIC guidelines for the "management of patients at risk of allergic reactions to Covid-19 vaccines" [1]. Results. 10/362 (0.02%) had positive skin test to one or both excipients in group 1, 12/169 (7.1%) in group 2 (p less than 0.01). In group 2 HRs to Covid-19 vaccines were immediate in 10/12 of cases and anaphylaxis occurred in 4/12 of patients. Conclusions. The positivity of skin test with PEG and or PS before vaccination is extremely rare and mostly replaceable by an accurate clinical history. Sensitization to PEG and PS has to be investigated in patients with a previous immediate HR to a Covid-19 vaccine, in particular in patients with anaphylaxis.


Assuntos
Anafilaxia , COVID-19 , Hipersensibilidade Imediata , Humanos , Polissorbatos/efeitos adversos , Polietilenoglicóis/efeitos adversos , Vacinas contra COVID-19/efeitos adversos , COVID-19/epidemiologia , COVID-19/prevenção & controle , Excipientes/efeitos adversos , Anafilaxia/diagnóstico , Anafilaxia/epidemiologia , Estudos Retrospectivos , Programas de Imunização , Testes Cutâneos , Itália/epidemiologia
4.
J Thromb Haemost ; 15(12): 2388-2392, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-28976612

RESUMO

Essentials Thrombocytopenia 2 (THC2) is an inherited thrombocytopenia (IT) with dysmegakaryopoiesis. Physicians often do not suspect the genetic origin of thrombocytopenia in patients with THC2. We report two THC2 patients misdiagnosed with myelodysplasia and treated with chemotherapy. IT should be always considered in patients with isolated thrombocytopenia and dysmegakaryopoiesis. SUMMARY: Thrombocytopenia 2 (THC2) is an autosomal-dominant disorder caused by point substitutions in the 5'UTR of the ANKRD26 gene. Patients have congenital thrombocytopenia, normal platelet morphology and function, and dysmegakaryopoiesis. Thrombocytopenia is frequently discovered only in adulthood and physicians often do not suspect its genetic origin. We describe two unrelated patients referred to two different institutions for investigation of thrombocytopenia. Based on the finding of dysmegakaryopoiesis at bone marrow examination, patients were diagnosed with myelodysplastic syndrome (MDS) (refractory thrombocytopenia) and treated with several courses of 5-azacytidine. Subsequently, demonstration of thrombocytopenia in their relatives eventually led to molecular diagnosis of THC2 in both families. These cases highlight that patients with THC2 are at risk of being misdiagnosed with MDS and receiving undue myelosuppressive treatments. Because dysmegakaryopoiesis is a feature also of other forms of inherited thrombocytopenia, a genetic disorder must always be considered when a patient presents with isolated thrombocytopenia and dysmegakaryopoiesis.


Assuntos
Transtornos Cromossômicos/diagnóstico , Transtornos Cromossômicos/genética , Mutação , Síndromes Mielodisplásicas/diagnóstico , Proteínas Nucleares/genética , Trombocitopenia/congênito , Idoso , Medula Óssea/patologia , Quebra Cromossômica , Transtornos Cromossômicos/patologia , Análise Mutacional de DNA , Erros de Diagnóstico , Predisposição Genética para Doença , Humanos , Peptídeos e Proteínas de Sinalização Intercelular , Masculino , Pessoa de Meia-Idade , Trombocitopenia/diagnóstico , Trombocitopenia/genética , Trombocitopenia/patologia , Trombopoese/genética
5.
Eur Ann Allergy Clin Immunol ; 49(4): 171-175, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28752720

RESUMO

SUMMARY: Omalizumab has recently obtained indication for chronic spontaneous urticaria both in the US and Europe. However, the mechanism of action of this drug has yet to be fully elucidated. Previous studies have shown elevations in cytokine serum levels in patients with chronic spontaneous urticaria, and it is not known whether omalizumab treatment may affect cytokine serum levels in this condition. Besides, a proportion of chronic spontaneous urticaria patients have concomitant atopy, which may be associated, at least in theory, with prevalence of serum Th2-type cytokines. In this study, serial serum samples from five patients (4 atopic and 1 nonatopic) with chronic spontaneous urticaria were assayed for cytokine concentrations by means of flow-cytometry-based multiplex bead assays, before and during omalizumab treatment. Omalizumab appeared to significantly affect the concentrations of multiple cytokines in a case of severe, long-lasting chronic spontaneous urticaria. Interestingly, IL-22 serum levels were found to progressively increase in three of five patients. Further studies are thus needed in larger patient populations, to conclusively establish whether the mechanism of action of omalizumab in chronic spontaneous urticaria also includes modulation of cytokine synthesis.


Assuntos
Antialérgicos/uso terapêutico , Citocinas/sangue , Mediadores da Inflamação/sangue , Omalizumab/uso terapêutico , Urticária/tratamento farmacológico , Adulto , Idoso , Biomarcadores/sangue , Doença Crônica , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Dados Preliminares , Estudos Retrospectivos , Índice de Gravidade de Doença , Fatores de Tempo , Resultado do Tratamento , Urticária/sangue , Urticária/diagnóstico , Urticária/imunologia
6.
Int J Lab Hematol ; 38(4): 412-8, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27320760

RESUMO

INTRODUCTION: Thrombocytopenia-absent radius (TAR) syndrome is a rare autosomal recessive disease. Patients are compound heterozygotes for a loss-of-function allele, which in most cases is a large genomic deletion on chromosome 1q21.1 containing the RBM8A gene, and a noncoding variant located in the 5'UTR (rs139428292) or intronic (rs201779890) regions of RBM8A. As the molecular genetic testing in TAR requires multiple techniques for detection of copy-number variations (CNV) and nucleotide substitutions, we tested whether a next-generation sequencing (NGS) approach could identify both alterations. METHODS: Two unrelated families were analyzed with Ion PGM sequencing using a target panel of genes responsible for different forms of inherited thrombocytopenia. A statistical quantitative evaluation of amplicon coverage was performed to detect CNV, in particular those on the RBM8A gene. RESULTS: All the probands were apparently homozygous for the rare allele inherited by the father at the rs139428292 locus, suggesting the presence of a deletion on the maternal chromosome. The statistical analysis confirmed the hemizygous condition of RBM8A. CONCLUSION: We concluded that NGS approaches could be used as a cost-effective method for molecular investigation of TAR as they could simultaneously detect CNV and point mutations.


Assuntos
Técnicas de Diagnóstico Molecular/normas , Proteínas de Ligação a RNA/genética , Trombocitopenia/diagnóstico , Deformidades Congênitas das Extremidades Superiores/diagnóstico , Adulto , Deleção Cromossômica , Síndrome Congênita de Insuficiência da Medula Óssea , Variações do Número de Cópias de DNA/genética , Família , Feminino , Humanos , Masculino , Técnicas de Diagnóstico Molecular/métodos , Rádio (Anatomia) , Análise de Sequência de DNA/métodos , Análise de Sequência de DNA/normas , Trombocitopenia/genética , Deformidades Congênitas das Extremidades Superiores/genética
7.
Clin Genet ; 89(2): 154-62, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25951879

RESUMO

Inherited thrombocytopenias (IT) are a heterogeneous group of diseases caused by at least 20 different genes. At present, these genes account for approximately 50% of cases, suggesting that novel genes have yet to be identified for a comprehensive understanding of platelet biogenesis defects. This review provides an update of ITs focusing on the molecular basis and potential pathogenic mechanisms affecting megakaryopoiesis and platelet production.


Assuntos
Doenças Genéticas Inatas/genética , Trombocitopenia/genética , Plaquetas/metabolismo , Eritropoese/genética , Humanos , Megacariócitos/metabolismo , Transdução de Sinais/genética
8.
Clin Genet ; 88(1): 85-9, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24890873

RESUMO

MYH9-related disease (MYH9-RD) is a rare autosomal dominant disease caused by mutation of MYH9, the gene encoding for the heavy chain of non-muscle myosin IIA (NMMHC-IIA). MYH9-RD patients have macrothrombocytopenia and granulocyte inclusions (pathognomonic sign of the disease) containing wild-type and mutant NMMHC-IIA. During life they might develop sensorineural hearing loss, cataract, glomerulonephritis, and elevation of liver enzymes. One of the MYH9 mutations, p.R705H, was previously reported to be associated with DFNA17, an autosomal dominant non-syndromic sensorineural hearing loss without any other features associated. We identified the same mutation in two unrelated families, whose four affected individuals had not only hearing impairment but also thrombocytopenia, giant platelets, leukocyte inclusions, as well as mild to moderate elevation of some liver enzymes. Our data suggest that DFNA17 should not be a separate genetic entity but part of the wide phenotypic spectrum of MYH9-RD characterized by congenital hematological manifestations and variable penetrance and expressivity of the extra-hematological features.


Assuntos
Perda Auditiva Neurossensorial/genética , Proteínas Motores Moleculares/genética , Mutação de Sentido Incorreto , Cadeias Pesadas de Miosina/genética , Trombocitopenia/congênito , Adolescente , Adulto , Pré-Escolar , Feminino , Perda Auditiva Neurossensorial/diagnóstico , Humanos , Masculino , Pessoa de Meia-Idade , Linhagem , Fenótipo , Trombocitopenia/diagnóstico , Trombocitopenia/genética
10.
Pituitary ; 17(5): 457-63, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24122272

RESUMO

PURPOSE: Detection of antipituitary antibodies (APA) at high levels and with a particular immunofluorescence pattern in patients with autoimmune polyendocrine syndromes may indicate a possible future autoimmune pituitary involvement. This longitudinal study was aimed at characterizing in patients with a single organ-specific autoimmune disease the pituitary cells targeted by APA at start, verifying whether this characterization allows to foresee the kind of possible subsequent hypopituitarism. METHODS: Thirty-six APA positive and 40 APA negative patients with isolated autoimmune diseases participated in the study. None of them had pituitary dysfunction at entry. Characterization by four-layer immunofluorescence of pituitary cells targeted by APA in APA positive patients at entry and study of pituitary function in all patients were performed every 6 months during a 5 year follow-up. RESULTS: Antipituitary antibodies immunostained selectively one type of pituitary-secreting cells in 21 patients (58.3 %, group 1), and several types of pituitary cells in the remaining 15 (41.7 %, group 2). All patients in group 1 showed subsequently a pituitary insufficiency, corresponding to the type of cells targeted by APA in 18 of them (85.7 %). Only 8 out of 15 patients in group 2 (53.3 %) showed a hypopituitarism, isolated in 7 and combined in the other one. None of APA negative patients showed hypopituitarism. CONCLUSIONS: The characterization of pituitary cells targeted by APA in patients with isolated autoimmune diseases, when the pituitary function is still normal, may help to foresee the kind of subsequent hypopituitarism, especially when APA immunostained selectively only one type of pituitary cells. A careful follow-up of pituitary function in these patients is advisable to allow an early diagnosis of hypopituitarism, even in subclinical phase and a consequent timely replacement therapy.


Assuntos
Autoanticorpos/imunologia , Doenças Autoimunes/imunologia , Hipofisite Autoimune/imunologia , Hipopituitarismo/imunologia , Hipófise/citologia , Hipófise/imunologia , Adulto , Feminino , Humanos , Estudos Longitudinais , Masculino
12.
J Thromb Haemost ; 11(6): 1006-19, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23510089

RESUMO

The diagnosis of inherited thrombocytopenias is difficult, for many reasons. First, as they are all rare diseases, they are little known by clinicians, who therefore tend to suspect the most common forms. Second, making a definite diagnosis often requires complex laboratory techniques that are available in only a few centers. Finally, half of the patients have forms that have not yet been described. As a consequence, many patients with inherited thrombocytopenias are misdiagnosed with immune thrombocytopenia, and are at risk of receiving futile treatments. Misdiagnosis is particularly frequent in patients whose low platelet count is discovered in adult life, because, in these cases, even the inherited origin of thrombocytopenia may be missed. Making the correct diagnosis promptly is important, as we recently learned that some forms of inherited thrombocytopenia predispose to other illnesses, such as leukemia or kidney failure, and affected subjects therefore require close surveillance and, if necessary, prompt treatments. Moreover, medical treatment can increase platelet counts in specific disorders, and affected subjects can therefore receive drugs instead of platelet transfusions when selective surgery is required. In this review, we will discuss how to suspect, diagnose and manage inherited thrombocytopenias, with particular attention to the forms that frequently present in adults. Moreover, we describe four recently identified disorders that belong to this group of disorders that are often diagnosed in adults: MYH9-related disease, monoallelic Bernard-Soulier syndrome, ANKRD26-related thrombocytopenia, and familial platelet disorder with predisposition to acute leukemia.


Assuntos
Doenças Hematológicas/diagnóstico , Doenças Hematológicas/genética , Trombocitopenia/diagnóstico , Trombocitopenia/genética , Adulto , Síndrome de Bernard-Soulier/diagnóstico , Transtornos Plaquetários/diagnóstico , Plaquetas/citologia , Diagnóstico Diferencial , Predisposição Genética para Doença , Humanos , Peptídeos e Proteínas de Sinalização Intercelular , Leucemia/sangue , Leucemia/genética , Leucemia Mieloide Aguda/diagnóstico , Pessoa de Meia-Idade , Proteínas Motores Moleculares/genética , Cadeias Pesadas de Miosina/genética , Proteínas Nucleares/genética , Contagem de Plaquetas
13.
J Thromb Haemost ; 10(8): 1653-61, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22672365

RESUMO

BACKGROUND: Inherited thrombocytopenias (ITs) are heterogeneous genetic disorders that frequently represent a diagnostic challenge. The requirement of highly specialized tests for diagnosis represents a particular problem in resource-limited settings. To overcome this difficulty, we applied a diagnostic algorithm and developed a collaboration program with a specialized international center in order to increase the diagnostic yield in a cohort of patients in Argentina. METHODS: Based on the algorithm, initial evaluation included collection of clinical data, platelet size, blood smear examination and platelet aggregation tests. Confirmatory tests were performed according to diagnostic suspicion, which included platelet glycoprotein expression, immunofluorescence for myosin-9 in granulocytes and platelet thrombospondin-1 and molecular screening of candidate genes. RESULTS: Thirty-one patients from 14 pedigrees were included; their median age was 32 (4-72) years and platelet count 72 (4-147)×10(9) L(-1). Autosomal dominant inheritance was found in nine (64%) pedigrees; 10 (71%) had large platelets and nine (29%) patients presented with syndromic forms. A definitive diagnosis was made in 10 of 14 pedigrees and comprised MYH9-related disease in four, while classic and monoallelic Bernard-Soulier syndrome, gray platelet syndrome, X-linked thrombocytopenia, thrombocytopenia 2 (ANKRD26 mutation) and familial platelet disorder with predisposition to acute myelogenous leukemia were diagnosed in one pedigree each. CONCLUSIONS: Adoption of an established diagnostic algorithm and collaboration with an expert referral center proved useful for diagnosis of IT patients in the setting of a developing country. This initiative may serve as a model to develop international networks with the goal of improving diagnosis and care of patients with these rare diseases.


Assuntos
Comportamento Cooperativo , Países em Desenvolvimento , Testes Genéticos , Testes Hematológicos , Cooperação Internacional , Trombocitopenia/diagnóstico , Adolescente , Adulto , Idoso , Algoritmos , Argentina , Biomarcadores/sangue , Criança , Pré-Escolar , Análise Mutacional de DNA , Estudos de Viabilidade , Feminino , Citometria de Fluxo , Imunofluorescência , Predisposição Genética para Doença , Testes Genéticos/métodos , Acessibilidade aos Serviços de Saúde , Testes Hematológicos/métodos , Hereditariedade , Humanos , Itália , Masculino , Pessoa de Meia-Idade , Proteínas Motores Moleculares/sangue , Cadeias Pesadas de Miosina/sangue , Linhagem , Fenótipo , Contagem de Plaquetas , Testes de Função Plaquetária , Valor Preditivo dos Testes , Prognóstico , Encaminhamento e Consulta , Trombocitopenia/sangue , Trombocitopenia/congênito , Trombospondina 1/sangue , Adulto Jovem
15.
Clin Endocrinol (Oxf) ; 69(2): 285-91, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18221394

RESUMO

OBJECTIVE: The occurrence of antipituitary antibodies (APA) in patients with idiopathic hyperprolactinaemia (IH) and the effects of dopamine agonists on these antibodies and long-term pituitary function outcome have been so far not evaluated. This longitudinal study was aimed at investigating, in patients with IH the occurrence of APA and the effect of cabergoline on the pituitary function and behaviour of APA. DESIGN: Sixty-six patients with IH were studied. APA (by indirect immunofluorescence) and pituitary function were investigated every year for 3 years. RESULTS: Seventeen patients resulted APA positive (Group 1) and 49 APA negative (Group 2). Eight patients of Group 1 (Group 1a) and 24 of Group 2 (Group 2a) were asymptomatic and then not treated; instead, nine patients in Group 1 (Group 1b) and 25 in Group 2 (Group 2b), showing symptoms of hyperprolactinaemia, were treated with cabergoline for 2 years. Among the untreated patients, during the follow-up, those with APA positive (Group 1a) showed an increase of APA titres and PRL levels with partial pituitary impairment in some of them; instead those with APA negative (Group 2a) persisted negative with normal pituitary function despite persistent hyperprolactinaemia. Among the treated patients, those with APA positive (Group 1b) showed normalization of PRL levels, APA disappearance and recovery of pituitary function (when initially impaired) during cabergoline treatment, persisting also at last observation (off-therapy). Instead all patients of Group 2b persisted with APA negative during the follow-up with normalization of PRL levels and stable normal pituitary function during cabergoline therapy but showing a further increase of PRL at the last observation. CONCLUSIONS: The presence of APA in some patients with IH suggests a possible occurrence of autoimmune hypophysitis at potential/subclinical stage; an early and prolonged cabergoline therapy could interrupt the progression to an overt clinical stage of the disease. However, the small amount of patients investigated suggests caution against generalization of our assumption and prompts to further controlled studies on a more numerous population to verify these conclusions.


Assuntos
Autoanticorpos/sangue , Ergolinas/farmacologia , Ergolinas/uso terapêutico , Hiperprolactinemia/tratamento farmacológico , Hiperprolactinemia/imunologia , Hipófise/efeitos dos fármacos , Adulto , Doenças Autoimunes/induzido quimicamente , Doenças Autoimunes/epidemiologia , Cabergolina , Estudos de Coortes , Agonistas de Dopamina/efeitos adversos , Agonistas de Dopamina/farmacologia , Agonistas de Dopamina/uso terapêutico , Ergolinas/efeitos adversos , Feminino , Antagonistas de Hormônios/efeitos adversos , Antagonistas de Hormônios/farmacologia , Antagonistas de Hormônios/uso terapêutico , Humanos , Hiperprolactinemia/sangue , Hiperprolactinemia/epidemiologia , Estudos Longitudinais , Masculino , Doenças da Hipófise/induzido quimicamente , Doenças da Hipófise/epidemiologia , Testes de Função Hipofisária , Hipófise/imunologia , Hipófise/fisiopatologia , Estudos Soroepidemiológicos , Hormônios Tireóideos/sangue , Tireotropina/sangue , Fatores de Tempo
16.
Leukemia ; 21(1): 72-8, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17096012

RESUMO

Fanconi anemia (FA) is an autosomal recessive disease characterized by pancitopenia, congenital malformations, predisposition to cancers and chromosomal instability. We report the clinical and molecular features of a patient initially identified as a potential FA case only because of chemotherapy toxicity during the treatment of a T-lineage acute lymphoblastic leukemia (ALL). Cells from this patient showed a moderate chromosomal instability, increasing sensitivity to DNA crosslinking agents but normal response to ionizing radiation. The analysis of FA proteins demonstrated a marked reduction of FANCD2 (>95%), but normal levels of FANCA or FANCG. Interestingly, this defect was associated with a homozygous missense mutation of FANCD2, resulting in a novel amino-acid substitution (Leu153Ser) at residue Leu153, which is highly conserved through evolution. The FANCD2(L153S) protein, whose reduced expression was not due to impaired transcription, was detected also in its monoubiquitinated form in the nucleus, suggesting that the mutation does not affect post-translation modifications or subcellular localization but rather the stability of FANCD2. Therefore, the hypomorphic Leu153Ser mutation represents the first example of a FANCD2 defect that might promote clonal progression of tumors, such as T-ALL, and severe chemotherapy toxicity in patients without any clinical manifestations typical of FA.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Proteína do Grupo de Complementação D2 da Anemia de Fanconi/genética , Leucemia-Linfoma de Células T do Adulto/tratamento farmacológico , Leucemia-Linfoma de Células T do Adulto/genética , Mutação , Substituição de Aminoácidos , Antígenos CD , Antígenos de Diferenciação Mielomonocítica , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Antígenos CD13 , Criança , Instabilidade Cromossômica , Progressão da Doença , Anemia de Fanconi/genética , Humanos , Infecções/etiologia , Infecções/genética , Leucemia-Linfoma de Células T do Adulto/fisiopatologia , Masculino , Pancitopenia/induzido quimicamente , Pancitopenia/genética , Indução de Remissão , Lectina 3 Semelhante a Ig de Ligação ao Ácido Siálico
17.
Tech Coloproctol ; 10(4): 361-3, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17115306

RESUMO

We report the case of a patient treated with the stapled transanal rectal resection (STARR) procedure for obstructed defecation, who developed an early postoperative haematoma of the posterior vaginal wall and, after 30 days, a rectovaginal fistula (RVF), even though the intervention had been performed according to the standardized technique. After clinical examination and three-dimensional anal endosonography, we carried out a successful surgical correction with double vaginal and rectal flaps with repair of the rectovaginal septum and without faecal diversion. The STARR procedure, even if performed according to a rigorous application of the methodological standards, may be followed by a RVF possibly due to a blood collection leading to ischaemia of the vaginal wall.


Assuntos
Hematoma/etiologia , Obstrução Intestinal/cirurgia , Doenças Retais/cirurgia , Fístula Retovaginal/etiologia , Grampeamento Cirúrgico/efeitos adversos , Doenças Vaginais/etiologia , Feminino , Humanos , Pessoa de Meia-Idade , Fístula Retovaginal/diagnóstico , Fístula Retovaginal/cirurgia , Retalhos Cirúrgicos
18.
J Thromb Haemost ; 4(4): 848-60, 2006 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16634756

RESUMO

BACKGROUND: Megakaryopoiesis represents a multi-step, often unclear, process leading to commitment, differentiation, and maturation of megakaryocytes (MKs) that release platelets. AIM: To identify the novel genes that might help to clarify the molecular mechanisms of megakaryocytopoiesis and be regarded as potential candidates of inherited platelet defects, global gene expression of hematopoietic lineages was carried out. METHODS: Human cord blood was used to purify CD34+ stem cells and in vitro expand CD41+ cells and burst-forming unit-erythroid (BFU-E). We investigated the expression profiles of these three hematopoietic lineages in the Affymetrix system and selected genes specifically expressed in MKs by comparing transcripts of the different lineages using the dchip and pam algorithms. RESULTS: A detailed characterization of MK population showed that 99% of cells expressed the CD41 antigen whereas 73% were recognizable as terminally differentiated fetal MKs. The profile of these cells was compared with that of CD34+ cells and BFU-E allowing us to select 70 transcripts (MK-core), which represent not only the genes with a well-known function in MKs, but also novel genes never detected or characterized in these cells. Moreover, the specific expression was confirmed at both RNA and protein levels, thus validating the 'MK-core' isolated by informatics tools. CONCLUSIONS: This is a global gene expression that for the first time depicts a well-characterized population of cord blood-derived fetal MKs. Novel genes have been detected, such as those encoding components of the extracellular matrix and basal membrane, which have been found in the cytoplasm of Mks, suggesting that new physiological aspects of MKs should be studied.


Assuntos
Sangue Fetal/citologia , Glicoproteína IIb da Membrana de Plaquetas/biossíntese , Trombopoese/fisiologia , Anticorpos Monoclonais/metabolismo , Antígenos CD34/biossíntese , Antígenos CD34/metabolismo , Células Precursoras Eritroides/metabolismo , Citometria de Fluxo , Humanos , Técnicas In Vitro , Microscopia de Fluorescência , Família Multigênica , Análise de Sequência com Séries de Oligonucleotídeos , Glicoproteína IIb da Membrana de Plaquetas/química , RNA/química , RNA/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa
19.
Phys Rev Lett ; 88(18): 185503, 2002 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-12005695

RESUMO

The transmission of monochromatic x rays through a CoO single crystal was measured for different orientations of the sample. The small variations in the linear absorption coefficient were considered as a hologram and the real-space image of the local atomic environment was successfully reconstructed. The holographic signal constituted about 1% of the detected intensity. Besides other benefits, the use of the absorption holography can increase the signal-to-background ratio by more than 1 order compared with the fluorescence holography.

20.
J Endocrinol Invest ; 25(5): 442-6, 2002 May.
Artigo em Inglês | MEDLINE | ID: mdl-12035941

RESUMO

Despite the observation that parity may increase the risk of thyroid carcinoma, very few studies have investigated the possible repercussion of parity on thyroid benign pathology. Recently, parity has been identified as one of the factors contributing to a larger thyroid size in healthy females. The aim of this work was to investigate a possible role for parity on the prevalence of multinodular goiter in iodine deficient areas. For this purpose, the reproductive histories of 2 cohorts of women, normal (Group I, 235 cases) and non-toxic multinodular goiter (NTMNG) affected (Group II, 274 cases) were compared. All subjects were euthyroid and had no previous history of thyroid function abnormalities. The number of full-term previous pregnancies (2.55+/-0.11 vs 1.77+/-0.10) and age (47.7+/-0.76 vs 42.3+/-0.83 yr) were found significantly higher (p<0.001) in multinodular goiter (MNG) patients than controls. Parity and age were found to be directly correlated (p<0.001), nevertheless the partial correlation coefficients demonstrated an independent and statistically significant difference for both variables between normal and NTMNG. Therefore, the independent effects of parity and age were further investigated. The effect of age on NTMNG prevalence seems to be weaker, in fact significant differences (p<0.001) for age between patients and controls were detected only when the effect of parity was absent (nulliparous), while with increasing gestations the effect of age disappeared. Our results indicate that age plays a minor role compared to parity which can therefore be considered as a stronger risk factor. In conclusion, the present study shows that, at least in iodine deficient regions, non-toxic multinodular goiter women show a statistically significant higher parity rate than healthy controls. Age may play a certain role but only when additional stronger risk factors are absent.


Assuntos
Bócio Nodular/epidemiologia , Iodo/deficiência , Paridade , Adulto , Envelhecimento/fisiologia , Deficiências Nutricionais/epidemiologia , Feminino , Humanos , Itália/epidemiologia , Pessoa de Meia-Idade , Prevalência , Fatores de Risco
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