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1.
Front Endocrinol (Lausanne) ; 15: 1414785, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39314520

RESUMO

Objective: Critically ill patients, including those with brain injuries (BI), are frequently hospitalized in an intensive care unit (ICU). As with other critical states, an adequate stress response is essential for survival. Research on the hypothalamic-pituitary-adrenal gland (HPA) axis function in BI has primarily focused on assessing ACTH and cortisol levels. However, the immunological, metabolic, and hemodynamic effects of glucocorticoids (GCs) are mediated through the glucocorticoid receptor (GCR), a ubiquitously distributed intracellular receptor protein. Data on GCR-α expression and its signaling in acute BI injury are lacking. Methods: We designed a prospective observational study, carried out in one academic multi-disciplinary ICU. Forty-two critically ill patients with acute (BI)were included. These patients suffered from traumatic BI (N= 20), subarachnoid hemorrhage (N= 12), intracranial hemorrhage (N= 7), or ischemic stroke (N= 3). All patients were steroid-free. Twenty-four age and sex-matched healthy controls were used for comparison. Results: Expression of GCR-α and the glucocorticoid-inducible leucine zipper (GILZ), serum cortisol, interleukins (IL) 6, 8, 10 and TNF- α, and the BI biomarkers glial fibrillary acidic protein (GFAP) and total Tau were measured on ICU admission (within 48 hours) and 5-7 days from admission. Compared to healthy controls, in the critically ill patients with BI, GCR-α mRNA expression was significantly downregulated on admission, and after 5-7 days in the ICU (2.3-fold, p<0.05 and 2.6-fold, p<0.01, respectively). Even though GCR-α was downregulated, its downstream gene, GILZ, was expressed at the same levels as in normal controls on admission and was significantly upregulated 5-7 days following admission (2-fold, p<0.001). TNF-α levels were undetectable at both time-points. GCR-α expression levels inversely correlated with IL-6. The levels of cortisol and the BI biomarkers did not differ between the 2 time-points. Conclusions: We provide novel evidence on the downregulated expression and upregulated signaling of the ligand-binding and functionally active GCR-α isoform in the polymorphonuclear neutrophils (PMNs) of critically ill patients with BI. The increased GILZ expression indicates an increased GC sensitivity in the PMNs of BI critically ill patients.


Assuntos
Lesões Encefálicas , Estado Terminal , Neutrófilos , Receptores de Glucocorticoides , Humanos , Receptores de Glucocorticoides/metabolismo , Masculino , Feminino , Pessoa de Meia-Idade , Estudos Prospectivos , Neutrófilos/metabolismo , Adulto , Lesões Encefálicas/metabolismo , Lesões Encefálicas/sangue , Idoso , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genética , Hidrocortisona/sangue , Hidrocortisona/metabolismo , Glucocorticoides , Lesões Encefálicas Traumáticas/metabolismo , Zíper de Leucina
2.
J Endocrinol Invest ; 47(3): 721-728, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37702927

RESUMO

PURPOSE: We aimed to identify whether hypothalamic-pituitary-adrenal (HPA) axis dysfunction is related to deterioration in a percentage of patients who progress to severe COVID-19. METHODS: In this cohort observational study, we evaluated HPA axis activation by measuring cortisol, adrenocorticotropic hormone (ACTH), dehydroepiandrosterone sulfate (DHEA-S) levels, whole blood expression levels of the key glucocorticoid receptor, GCR-α, and the glucocorticoid-induced leucine zipper (GILZ), and cytokines, as markers of the inflammatory phase, in 149 patients with respiratory infection admitted in the ward, without known adrenal disease and/or confounding medications (glucocorticoids). One hundred and four (104) patients were SARS-CoV-2 positive (C +) and controls consisted of 45 SARS-CoV-2-negative patients (NC). RESULTS: No differences in cortisol levels were observed between the C + and the NC patients. Cortisol levels correlated with ACTH (r = 0.284, p = 0.001) and IL-6 (r = 0.289, p = 0.04). In C + patients, cortisol levels mainly correlated with IL-6 levels (r = 0.28; p = 0.017). GCR-α expression was significantly higher in C + patients compared to NC. Patients with higher cortisol levels were more likely to progress to respiratory function deterioration or die. Both GCR-α and GILZ expression were significantly higher in C + non-survivors. CONCLUSION: Our findings indicate that cortisol serves as an indicator of disease severity. GILZ expression appears to be a more effective marker of mortality prediction in moderate COVID-19 cases. However, routine measurement of GILZ levels is currently unavailable. Elevated levels of cortisol may be indicative of patients with moderate COVID-19 who are at a higher risk of deterioration. This information can aid in identifying individuals who require early medical attention.


Assuntos
COVID-19 , Citocinas , Humanos , Hidrocortisona , Sistema Hipotálamo-Hipofisário , Interleucina-6 , Sistema Hipófise-Suprarrenal , SARS-CoV-2 , Hormônio Adrenocorticotrópico
3.
Hum Reprod ; 38(12): 2526-2535, 2023 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-37814912

RESUMO

STUDY QUESTION: In oocytes of advanced maternal age (AMA) women, what are the mechanisms leading to aneuploidy and what is the association of aneuploidy with embryo development? SUMMARY ANSWER: Known chromosome segregation errors such as precocious separation of sister chromatids explained 90.4% of abnormal chromosome copy numbers in polar bodies (PBs), underlying impaired embryo development. WHAT IS KNOWN ALREADY: Meiotic chromosomal aneuploidies in oocytes correlate with AMA (>35 years) and can affect over half of oocytes in this age group. This underlies the rationale for PB biopsy as a form of early preimplantation genetic testing for aneuploidy (PGT-A), as performed in the 'ESHRE STudy into the Evaluation of oocyte Euploidy by Microarray analysis' (ESTEEM) randomized controlled trial (RCT). So far, chromosome analysis of oocytes and PBs has shown that precocious separation of sister chromatids (PSSC), Meiosis II (MII) non-disjunction (ND), and reverse segregation (RS) are the main mechanisms leading to aneuploidy in oocytes. STUDY DESIGN, SIZE, DURATION: Data were sourced from the ESTEEM study, a multicentre RCT from seven European centres to assess the clinical utility of PGT-A on PBs using array comparative genomic hybridization (aCGH) in patients of AMA (36-40 years). This included data on the chromosome complement in PB pairs (PGT-A group), and on embryo morphology in a subset of embryos, up to Day 6 post-insemination, from both the intervention (PB biopsy and PGT-A) and control groups. PARTICIPANTS/MATERIALS, SETTING, METHODS: ESTEEM recruited 396 AMA patients: 205 in the intervention group and 191 in the control group. Complete genetic data from 693 PB pairs were analysed. Additionally, the morphology from 1034 embryos generated from fertilized oocytes (two pronuclei) in the PB biopsy group and 1082 in the control group were used for statistical analysis. MAIN RESULTS AND THE ROLE OF CHANCE: Overall, 461/693 PB pairs showed abnormal segregation in 1162/10 810 chromosomes. The main observed abnormal segregations were compatible with PSSC in Meiosis I (MI) (n = 568/1162; 48.9%), ND of chromatids in MII or RS (n = 417/1162; 35.9%), and less frequently ND in MI (n = 65/1162; 5.6%). For 112 chromosomes (112/1162; 9.6%), we observed a chromosome copy number in the first PB (PB1) and second PB (PB2) that is not explained by any of the known mechanisms causing aneuploidy in oocytes. We observed that embryos in the PGT-A arm of the RCT did not have a significantly different morphology between 2 and 6 days post-insemination compared to the control group, indicating that PB biopsy did not affect embryo quality. Following age-adjusted multilevel mixed-effect ordinal logistic regression models performed for each embryo evaluation day, aneuploidy was associated with a decrease in embryo quality on Day 3 (adjusted odds ratio (aOR) 0.62, 95% CI 0.43-0.90), Day 4 (aOR 0.15, 95% CI 0.06-0.39), and Day 5 (aOR 0.28, 95% CI 0.14-0.58). LIMITATIONS, REASON FOR CAUTION: RS cannot be distinguished from normal segregation or MII ND using aCGH. The observed segregations were based on the detected copy number of PB1 and PB2 only and were not confirmed by the analysis of embryos. The embryo morphology assessment was static and single observer. WIDER IMPLICATIONS OF THE FINDINGS: Our finding of frequent unexplained chromosome copy numbers in PBs indicates that our knowledge of the mechanisms causing aneuploidy in oocytes is incomplete. It challenges the dogma that aneuploidy in oocytes is exclusively caused by mis-segregation of chromosomes during MI and MII. STUDY FUNDING/COMPETING INTEREST(S): Data were mined from a study funded by ESHRE. Illumina provided microarrays and other consumables necessary for aCGH testing of PBs. None of the authors have competing interests. TRIAL REGISTRATION NUMBER: Data were mined from the ESTEEM study (ClinicalTrials.gov Identifier NCT01532284).


Assuntos
Diagnóstico Pré-Implantação , Gravidez , Feminino , Humanos , Idade Materna , Diagnóstico Pré-Implantação/métodos , Aneuploidia , Oócitos , Desenvolvimento Embrionário/genética
4.
J Hosp Infect ; 139: 240-248, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37392869

RESUMO

BACKGROUND: Novel molecular diagnostic methods are being evaluated in order to expedite pathogen identification in patients with bacteraemia. AIMS: To evaluate the feasibility and diagnostic accuracy of the T2 magnetic resonance (T2MR) assays - T2 Bacteria (T2B) and T2 Resistance (T2R) - as point-of-care tests in the intensive care unit compared with blood-culture-based tests. METHODS: Prospective cross-sectional study of consecutive patients with suspected bacteraemia. Diagnostic accuracy was evaluated using blood culture as the reference method. FINDINGS: In total, 208 cases were included in the study. The mean time from sampling to report was lower for the T2MR assays compared with blood-culture-based methods (P<0.001). The rate of invalid reports was 6.73% for the T2B assay and 9.9% for the T2R assay. For the T2B assay, overall positive percentage agreement (PPA) was 84.6% [95% confidence interval (CI) 71.9-93.1%], negative percentage agreement (NPA) was 64.3% (95% CI 55.4-72.6%), positive predictive value (PPV) was 48.9% (95% CI 42.5-55.3%) and negative predictive value (NPV) was 91.2% (95% CI 84.4-95.2%). Cohen's kappa coefficient was 0.402. For the T2R assay, overall PPA was 80% (95% CI 51.9-95.7%), NPA was 69.2% (95% CI 54.9-81.3%), PPV was 42.9% (95% CI 31.7-54.8%) and NPV was 92.3% (95% CI 81.1-97.1%). Cohen's kappa coefficient was 0.376. CONCLUSION: T2MR assays have high NPV for rapid exclusion of bacteraemia, and could potentially assist with antimicrobial stewardship when applied as point-of-care diagnostic tests in the intensive care unit.


Assuntos
Bacteriemia , Sistemas Automatizados de Assistência Junto ao Leito , Humanos , Estudos Prospectivos , Estudos Transversais , Espectroscopia de Ressonância Magnética/métodos , Bacteriemia/diagnóstico , Unidades de Terapia Intensiva , Sensibilidade e Especificidade
6.
Int J Lab Hematol ; 40 Suppl 1: 74-82, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29741247

RESUMO

The hemoglobinopathies, as a group, are one of the most common serious monogenic diseases in the world. An accepted and widely adopted approach to reduce the number of new cases involves carrier-screening programs, with the option of prenatal diagnosis (PND) or preimplantation diagnosis (preimplantation genetic testing for monogenic disease, PGT-M) for carrier couples. The aim of PND is to provide an accurate result as early in pregnancy as possible, which necessitates prior identification of the parental disease-causing mutations, as well as safe and timely biopsy of fetal material. PGT-M aims to characterize the genetic status of in vitro fertilized embryos during assisted reproductive technology (ART), in a few cells biopsied from oocytes/zygotes or embryos, in order to initiate an unaffected pregnancy. Another application of PGT-M is preimplantation genetic diagnosis for human leukocyte antigen (PGD-HLA), which, in addition to identifying unaffected embryos, also characterizes the embryos that are HLA compatible with an existing affected child requiring a hemopoietic stem cell transplantation (HSCT). This review outlines the current practices related to these procedures, with emphasis on the aspects related to laboratory techniques. Finally, future prospects related to developments in noninvasive prenatal diagnosis are discussed.


Assuntos
Hemoglobinopatias/diagnóstico , Diagnóstico Pré-Implantação/métodos , Diagnóstico Pré-Natal/métodos , Técnicas de Laboratório Clínico , Feminino , Testes Genéticos/métodos , Antígenos HLA/análise , Humanos , Gravidez
7.
J Cyst Fibros ; 15(2): 163-70, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26493493

RESUMO

BACKGROUND: Institutions offering CF-PGD face the challenge of developing and optimizing single cell genotyping protocols that should cover for the extremely heterogeneous CF mutation spectrum. Here we report the development and successful clinical application of a generic CF-PGD protocol to facilitate direct detection of any CFTR nucleotide variation(s) by HRMA and simultaneous confirmation of diagnosis through haplotype analysis. METHODS: A multiplex PCR was optimized supporting co-amplification of any CFTR exon-region, along with 6 closely linked STRs. Single cell genotypes were established through HRM analysis following melting of the 2nd round PCR products and were confirmed by STR haplotype analysis of the 1st PCR products. The protocol was validated pre-clinically, by testing 208 single lymphocytes, isolated from whole blood samples from 4 validation family trios. Fifteen PGD cycles were performed and 103 embryos were biopsied. RESULTS: In 15 clinical PGD cycles, genotypes were achieved in 88/93 (94.6%) embryo biopsy samples, of which 57/88 (64.8%) were deemed genetically suitable for embryo transfer. Amplification failed at all loci for 10/103 blastomeres biopsied from poor quality embryos. Six clinical pregnancies were achieved (2 twin, 4 singletons). PGD genotypes were confirmed following conventional amniocentesis or chorionic villus sampling in all achieved pregnancies. CONCLUSIONS: The single cell HRMA CF-PGD protocol described herein is a flexible, generic, low cost and robust genotyping method, which facilitates the analysis of any CFTR genotype combination. Single-cell HRMA can be beneficial to other clinical settings, for example the detection of single nucleotide variants in single cells derived from clinical tumor samples.


Assuntos
Regulador de Condutância Transmembrana em Fibrose Cística/genética , Fibrose Cística/diagnóstico , Mutação , Diagnóstico Pré-Implantação/métodos , RNA/genética , Adulto , Blastômeros , Linhagem Celular , Fibrose Cística/genética , Fibrose Cística/metabolismo , Regulador de Condutância Transmembrana em Fibrose Cística/metabolismo , Éxons , Feminino , Marcadores Genéticos , Genótipo , Haplótipos , Humanos , Reação em Cadeia da Polimerase , Gravidez
8.
Br J Anaesth ; 112(2): 298-303, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24067331

RESUMO

BACKGROUND: This study was to evaluate the usefulness of hepato-biliary ultrasound (HBUS) for the investigation of isolated liver function tests (LFTs) abnormalities. METHODS: We retrospectively reviewed HBUS reports in traumatic brain injury (TBI) patients admitted to our tertiary neuro-critical care unit (NCCU; January 2005-June 2011). We included patients receiving an HBUS for isolated LFTs derangement, excluding pre-existing hepato-biliary diseases or trauma. We assessed the temporal profile of alanine aminotransferase (ALT), bilirubin (Bil), and alkaline phosphatase (ALP). RESULTS: Of 511 patients, 58 received an HBUS. Of these, 47 were investigated for isolated LFTs derangement; HBUS always failed to identify a cause for these abnormalities. The HBUS was performed on day 18 (range 6-51) with the following mean values: 246 IU litre(-1) [ALT, 95% confidence interval (CI) 183-308], 24 µmol litre(-1) (Bil, 95% CI 8-40), and 329 IU litre(-1) (ALP, 95% CI 267-390); only ALT (72, 95% CI 36-107) and ALP (73, 95% CI 65-81) were deranged from admission values (both P<0.01). At NCCU discharge, both ALT (160, 95% CI 118-202) and ALP (300, 95% CI 240-360) were higher than at admission (P<0.01). Compared with HBUS-day value, only ALT improved by NCCU discharge (P<0.05), while both were recovering by hospital discharge (ALT 83, 95% CI 59-107; ALP 216, 95% CI 181-251; P<0.01). At hospital discharge, ALP remained higher than at admission (P<0.01). CONCLUSIONS: In TBI patients, HBUS did not appear sensitive in detecting causes for isolated LFT abnormalities. Both ALT and ALP worsened and gradually recovered. Their abnormalities did not prevent NCCU discharge. ALP recovered more slowly than ALT. TBI and its complications, critical illness, and pharmacological strategies may explain the LFTs derangement.


Assuntos
Ductos Biliares/diagnóstico por imagem , Lesões Encefálicas/complicações , Hepatopatias/complicações , Hepatopatias/diagnóstico , Fígado/diagnóstico por imagem , Adulto , Idoso , Alanina Transaminase/análise , Fosfatase Alcalina/análise , Bilirrubina/análise , Feminino , Hospitalização , Humanos , Tempo de Internação/estatística & dados numéricos , Testes de Função Hepática/métodos , Testes de Função Hepática/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Reprodutibilidade dos Testes , Estudos Retrospectivos , Ultrassonografia , Adulto Jovem
9.
Gene Ther ; 18(10): 996-1005, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21512505

RESUMO

We use both large and small animal models in our pre-clinical evaluation of gene transfer agents (GTAs) for cystic fibrosis (CF) gene therapy. Here, we report the use of a large animal model to assess three non-viral GTAs: 25 kDa-branched polyethyleneimine (PEI), the cationic liposome (GL67A) and compacted DNA nanoparticle formulated with polyethylene glycol-substituted lysine 30-mer. GTAs complexed with plasmids expressing human cystic fibrosis transmembrane conductance regulator (CFTR) complementary DNA were administered to the sheep lung (n=8 per group) by aerosol. All GTAs gave evidence of gene transfer and expression 1 day after treatment. Vector-derived mRNA was expressed in lung tissues, including epithelial cell-enriched bronchial brushing samples, with median group values reaching 1-10% of endogenous CFTR mRNA levels. GL67A gave the highest levels of expression. Human CFTR protein was detected in small airway epithelial cells in some animals treated with GL67A (two out of eight) and PEI (one out of eight). Bronchoalveolar lavage neutrophilia, lung histology and elevated serum haptoglobin levels indicated that gene delivery was associated with mild local and systemic inflammation. Our conclusion was that GL67A was the best non-viral GTA currently available for aerosol delivery to the sheep lung, led to the selection of GL67A as our lead GTA for clinical trials in CF patients.


Assuntos
Regulador de Condutância Transmembrana em Fibrose Cística/genética , Fibrose Cística/terapia , Técnicas de Transferência de Genes , Terapia Genética/métodos , Lipossomos/administração & dosagem , Nanopartículas/administração & dosagem , Polietilenoimina/administração & dosagem , Administração por Inalação , Animais , Fibrose Cística/genética , Regulador de Condutância Transmembrana em Fibrose Cística/metabolismo , DNA Complementar/administração & dosagem , DNA Complementar/genética , Humanos , Polietilenoglicóis , RNA Mensageiro/metabolismo , Ovinos
10.
Gene Ther ; 18(2): 182-8, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20962870

RESUMO

We have previously shown that recombinant Sendai virus (SeV) vector, derived from murine parainfluenza virus, is one of the most efficient vectors for airway gene transfer. We have also shown that SeV-mediated transfection on second administration, although reduced by 60% when compared with levels achieved after a single dose, is still high because of the efficient transfection achieved by SeV vector in murine airways. Here, we show that these levels further decrease on subsequent doses. In addition, we validated SeV vector repeat administration in a non-natural host model, the sheep. As part of these studies we first assessed viral stability in a Pari LC Plus nebuliser, a polyethylene catheter (PEC) and the Trudell AeroProbe. We also compared the distribution of gene expression after PEC and Trudell AeroProbe administration and quantified virus shedding after sheep transduction. In addition, we show that bronchial brushings and biopsies, collected in anaesthetized sheep, can be used to assess SeV-mediated gene expression over time. Similar to mice, gene expression in sheep was transient and had returned to baseline values by day 14. In conclusion, the SeV vector should be strongly considered for lung-related applications requiring a single administration of the vector even though it might not be suitable for diseases requiring repeat administration.


Assuntos
Expressão Gênica , Vetores Genéticos , Vírus Sendai/genética , Ovinos/genética , Transdução Genética , Animais , Catéteres , Feminino , Técnicas de Transferência de Genes/instrumentação , Pulmão , Camundongos , Camundongos Endogâmicos BALB C , Modelos Animais , Retratamento
11.
Infection ; 38(3): 173-80, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20224962

RESUMO

BACKGROUND: There has been an increasing incidence of carbapenem-resistant Acinetobacter baumannii (CRAB) infections in recent years. The objective of this study was to determine specific risk factors for and outcome of bacteremia due to CRAB isolates among our ICU patients with A. baumannii bacteremia. PATIENTS AND METHODS: Among 96 patients with ICU-acquired A. baumannii bacteremia, 30 patients with CRAB were compared with the remaining 66 with carbapenem-susceptible A. baumannii (CSAB) isolates. RESULTS: Recent ventilator-associated pneumonia (VAP) due to CRAB (OR 16.74, 95% CI 3.16-88.79, p = 0.001) and a greater number of intravascular devices (OR 3.93, 95% CI 1.9-13.0, p = 0.025) were independently associated with CRAB bacteremia acquisition. Patients with CRAB bacteremia had a lower severity of illness on admission than those with CSAB. Although, by univariate analysis, patients with CRAB were more likely to have had exposure to colistin, carbapenems and linezolid, multivariate analysis did not revealed any significant association. The mortality was not different between patients with CRAB and CSAB bacteremia (43.3 vs. 46.9%, p = 0.740). Severity of organ failure (OR 1.42, 95% CI 1.20-1.67, p = 0.001), and increased white blood cell (WBC) count (OR 1.09, 95% CI 1.01-1.19, p = 0.036), at bacteremia onset were independently associated with mortality. CONCLUSION: VAP due to CRAB and excess use of intravascular devices are the most important risk factors for CRAB bacteremia in our ICU. Severity of organ failure and WBC count at A. baumannii bacteremia onset are independently associated with mortality.


Assuntos
Infecções por Acinetobacter/microbiologia , Acinetobacter baumannii/efeitos dos fármacos , Bacteriemia/microbiologia , Carbapenêmicos/farmacologia , Infecção Hospitalar/microbiologia , Infecções por Acinetobacter/tratamento farmacológico , Infecções por Acinetobacter/epidemiologia , Acinetobacter baumannii/isolamento & purificação , Adulto , Idoso , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Bacteriemia/tratamento farmacológico , Bacteriemia/epidemiologia , Carbapenêmicos/uso terapêutico , Infecções Relacionadas a Cateter/tratamento farmacológico , Infecções Relacionadas a Cateter/epidemiologia , Infecções Relacionadas a Cateter/microbiologia , Infecção Hospitalar/tratamento farmacológico , Infecção Hospitalar/epidemiologia , Farmacorresistência Bacteriana , Feminino , Grécia/epidemiologia , Humanos , Unidades de Terapia Intensiva , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Pneumonia Associada à Ventilação Mecânica/tratamento farmacológico , Pneumonia Associada à Ventilação Mecânica/epidemiologia , Pneumonia Associada à Ventilação Mecânica/microbiologia , Estudos Prospectivos , Análise de Regressão , Fatores de Risco
12.
Reprod Biomed Online ; 19(3): 418-25, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19778490

RESUMO

X-linked genetic diseases include a wide range of disorders such as the dystrophinopathies. Additionally in some rare genetic diseases, severity of expression is gender dependent. Prevention of such disorders usually involves prenatal diagnosis and termination of affected pregnancies, while preimplantation genetic diagnosis (PGD) represents a specialized alternative that avoids pregnancy termination. To preclude the rejection of unaffected male embryos that cannot be differentiated from those affected when using fluorescence in-situ hybridization, a flexible protocol based on multiplex fluorescence polymerase chain reaction (PCR) was standardized and validated for gender determination in single cells, which can potentially incorporate any disease-specific locus. The final panel of nine loci included four loci on the Y chromosome, two on the X chromosome plus up to three microsatellite markers to either support the gender diagnosis or to further monitor extraneous contamination. The protocol, standardized on single lymphocytes, established a PCR efficiency of >93% for all loci with maximum allele dropout rates of 4%. Microsatellite analysis excluded external contamination and confirmed biallelic inheritance. Proof of principle for the simplicity and flexibility of the assay was demonstrated through its application to clinical PGD cycles for lipoid congenital adrenal hyperplasia, which presents a more severe clinical course in males, and Duchenne muscular dystrophy.


Assuntos
Doenças Genéticas Ligadas ao Cromossomo X/diagnóstico , Reação em Cadeia da Polimerase/métodos , Diagnóstico Pré-Implantação/métodos , Hiperplasia Suprarrenal Congênita/complicações , Hiperplasia Suprarrenal Congênita/diagnóstico , Hiperplasia Suprarrenal Congênita/genética , Feminino , Doenças Genéticas Ligadas ao Cromossomo X/genética , Loci Gênicos , Humanos , Lipidoses/complicações , Lipidoses/diagnóstico , Lipidoses/genética , Masculino , Repetições de Microssatélites/genética , Distrofia Muscular de Duchenne/diagnóstico , Distrofia Muscular de Duchenne/genética , Reação em Cadeia da Polimerase/normas , Gravidez , Reprodutibilidade dos Testes , Processos de Determinação Sexual , Fatores Sexuais
13.
Prenat Diagn ; 27(13): 1228-32, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17987605

RESUMO

Single nucleated red blood cells (NRBCs) isolated from maternal circulation were used for prenatal diagnosis of beta-thalassaemia. The study included 22 pregnant women in the first trimester, 6 carriers at risk for beta-thalassaemia and 16 noncarriers. Methodology involved enrichment of NRBCs by magnetic cell sorting (MACS) and microdissection of single NRBCs with a laser micromanipulation system. Single-cell genotyping based on nested real-time PCR for genotyping beta-globin gene mutations was performed followed by a multiplexed minifingerprinting to confirm the origin of the isolated cells and possible contamination. Two polymorphic markers (D13S314 and GABRB3) facilitated the identification of fetal NRBCs through comparison of allele sizes found in the respective parents. In this study, 224 single NRBCs were detached and transferred into individual PCR tubes. Allele amplification in at least one microsatellite marker was achieved in 128/224 cells. Minifingerprinting analysis showed that 22 cells were fetal, 26 maternal and 80 were noninformative due to ADO or homozygosity. In 6 NRBCs the beta-globin gene was amplified and in 2, coming from the same pregnancy, only the paternal mutation was detected. The low PCR success when genotyping isolated NRBCs was possibly due to the poor quality of fetal NRBCs and the relatively large size of the beta-globin gene product.


Assuntos
Eritroblastos , Globinas/genética , Troca Materno-Fetal/genética , Diagnóstico Pré-Natal/métodos , Talassemia beta , Biomarcadores/sangue , Impressões Digitais de DNA , Feminino , Genótipo , Humanos , Repetições de Microssatélites , Reação em Cadeia da Polimerase , Gravidez , Primeiro Trimestre da Gravidez , Talassemia beta/diagnóstico , Talassemia beta/genética
14.
Hum Reprod ; 22(5): 1443-9, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17261575

RESUMO

BACKGROUND: Trophectoderm biopsy at the blastocyst stage is an emerging approach in preimplantation genetic diagnosis (PGD). This study aimed to compare genotyping success and implantation rates in PGD cycles for beta-thalassaemia following biopsy at the cleavage versus the blastocyst stage, with transfer of blastocysts. METHODS: This pilot study included 20 cycles: Group A: 10 cycles, day 3 blastomere biopsy, day 5 transfer; Group B: 10 cycles, day 5 trophectoderm biopsy, day 6 transfer. Standard-assisted reproduction and laser biopsy procedures were used. Biopsied cells were genotyped using real-time PCR multiplexed with fluorescent microsatellite analysis. RESULTS: In Group A, 131 fertilized eggs developed to 101 embryos suitable for single blastomere biopsy; 76/101 blastomeres were diagnosed (75.2%), 30 unaffected blastocysts were transferred resulting in six pregnancies (eight fetal hearts, 26.7% implantation rate). In Group B, 128 fertilized eggs developed to 53 blastocysts for trophectoderm biopsy (four to five cells), with 50/53 blastocysts diagnosed (94.3%), 21 unaffected blastocysts transferred and 6 pregnancies initiated (10 fetal hearts, 47.6% implantation rate). Overall, nine pregnancies reached >10 weeks gestation and were confirmed unaffected by prenatal diagnosis, with 12 healthy babies born. CONCLUSIONS: This pilot study suggests that trophectoderm biopsy and blastocyst transfer may be more advantageous than cleavage stage biopsy with respect to outcome of PGD for monogenic diseases.


Assuntos
Biópsia/métodos , Blastocisto , Fase de Clivagem do Zigoto , Diagnóstico Pré-Implantação/métodos , Talassemia beta/diagnóstico , Adulto , Transferência Embrionária , Feminino , Fertilização in vitro/métodos , Humanos , Masculino , Projetos Piloto , Gravidez
15.
Hum Reprod ; 20(7): 1855-9, 2005 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15878929

RESUMO

PGD is a well accepted reproductive choice for couples at genetic risk and involves the diagnosis and transfer of unaffected IVF embryos. PGD for monogenetic diseases is most commonly accomplished by the biopsy of one or two blastomeres from cleavage stage embryos, followed by PCR-based protocols. However, PCR-based DNA analysis of one or two cells is subject to several problems, including total PCR failure, or failure of one allele to amplify. Trophectoderm biopsy at the blastocyst stage enables the removal of more than two cells for diagnosis while being non-invasive to the inner cell mass which is destined for fetal development. The aim of this study was to develop a safe, reliable technique for the biopsy of trophectoderm cells from human blastocysts. This case report demonstrates that removal of trophectoderm cells prior to blastocyst transfer is compatible with implantation and development to term. Here we report successful PGD for beta-thalassaemia following trophectoderm cell biopsy from blastocysts and the birth of a healthy infant.


Assuntos
Blastocisto/citologia , Diagnóstico Pré-Implantação , Talassemia beta/diagnóstico , Talassemia beta/genética , Adulto , Sequência de Bases , Biópsia/métodos , DNA/genética , Transferência Embrionária , Feminino , Globinas/genética , Humanos , Recém-Nascido , Masculino , Reação em Cadeia da Polimerase , Gravidez , Trofoblastos/citologia
16.
Hum Reprod ; 17(1): 25-31, 2002 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11756357

RESUMO

BACKGROUND: Preimplantation genetic diagnosis (PGD) usually involves blastomere biopsy 3 days post-insemination (p.i.), followed by genetic analysis and transfer of unaffected embryos later on day 3 or 4. We evaluate a strategy involving embryo biopsy on day 3 p.i., genetic analysis on day 4 and, following culture in blastocyst sequential media, transfer of unaffected embryos on day 5 p.i. METHODS: PGD cycles were initiated in 15 couples at risk of transmitting beta-thalassaemia major. Oocyte retrieval and ICSI were performed according to standard protocols. Embryo culture used blastocyst sequential media. Embryos were biopsied on day 3 p.i. using acid Tyrode's for zona drilling, and the single blastomeres were genotyped by a protocol involving nested polymerase chain reaction and denaturing gradient gel electrophoresis analysis. RESULTS: Forty of 109 (37%) embryos biopsied on day 3 p.i. developed to blastocysts by day 5 p.i., with at least one blastocyst available for transfer in 12 cycles (80%). Genotype analysis characterized 51/109 (47%) embryos unaffected for beta-thalassaemia major, of which 28 were blastocysts. Transfer of 37 day 5 p.i. embryos (blastocysts and non blastocysts) initiated eight clinical pregnancies. Implantation rate per embryo transferred was 12/37 (32%). CONCLUSIONS: Embryo biopsy on day 3, followed by delayed transfer until day 5 p.i. offers a novel and effective strategy to overcome the time limit encountered when performing PGD, without compromising embryo implantation.


Assuntos
Blastocisto , Transferência Embrionária , Diagnóstico Pré-Implantação , Talassemia beta/diagnóstico , Talassemia beta/genética , Biópsia , Meios de Cultura , Feminino , Fertilização in vitro , Predisposição Genética para Doença , Genótipo , Heterozigoto , Humanos , Masculino , Técnicas de Cultura de Órgãos , Reação em Cadeia da Polimerase , Gravidez , Resultado da Gravidez , Injeções de Esperma Intracitoplásmicas , Fatores de Tempo
17.
Hemoglobin ; 25(1): 45-56, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11300349

RESUMO

Hb Sitia [beta128(H6)Ala-->Val] was found in a Greek female with slightly reduced red blood cell indices. The abnormal hemoglobin was indistinguishable from Hb A by electrophoresis but eluted after Hb A on cation exchange high performance liquid chromatography. DNA sequence analysis revealed a GCT-->GTT mutation at codon 128, which is predicted to encode an Ala-->Val substitution. This was confirmed by mass spectrometry analyses of the beta-globin chain. Since alanine at beta128(H6) interacts with several amino acids of the alpha1beta1 contact, its replacement by a larger residue results in a mild instability of the molecule and slight modifications of the oxygen binding properties.


Assuntos
Substituição de Aminoácidos , Globinas/genética , Hemoglobinopatias/genética , Hemoglobinas Anormais/isolamento & purificação , Mutação de Sentido Incorreto , Adulto , Cromatografia por Troca Iônica , Códon/genética , Análise Mutacional de DNA , Eritropoetina/sangue , Feminino , Globinas/biossíntese , Globinas/isolamento & purificação , Grécia , Corpos de Heinz/ultraestrutura , Hemoglobinopatias/sangue , Hemoglobinas Anormais/química , Hemoglobinas Anormais/genética , Humanos , Cinética , Espectrometria de Massas , Oxigênio/metabolismo , Ligação Proteica , Conformação Proteica , RNA Mensageiro/sangue , Receptores da Transferrina/sangue , Transcrição Gênica
18.
Haematologica ; 86(4): 363-7, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11325640

RESUMO

BACKGROUND AND OBJECTIVES: The degree of globin chain imbalance and tissue hypoxia are important determinants of clinical severity in thalassemia syndromes. Thus phenotypic expression may be modified by interaction of alpha- and beta-thalassemia defects, level and type of hemoglobin synthesized and oxygen release to the tissues. We evaluated hematology, erythroid marrow activity and functional anemia in patients with the rare interaction of a single a-globin gene and heterozygous beta-thalassemia (HbH/beta-thal trait). DESIGN AND METHODS: In 7 patients characterized by DNA analysis to have HbH disease genotypes with beta-thalassemia trait, we assessed hematologic findings, serum transferrin receptor (sTfR), serum erythropoietin (Epo), red cell 2,3-disphosphoglycerate (2,3-DPG) and whole blood oxygen releasing capability. RESULTS: Patients with HbH/beta-thal trait had moderate anemia, marked hypochromasia and microcytosis, normal or raised HbA2, and no electrophoretically/chromatographically detectable HbH. Epo and sTfR levels were significantly higher than in beta-thalassemia heterozygotes, but lower than in patients with HbH disease; 2,3-DPG levels were highest in HbH/beta-thal trait. Oxygen binding studies and simulations showed reduced oxygen affinity (P50) in HbH/beta-thal trait, resulting in increased oxygen release (O2R). INTERPRETATION AND CONCLUSIONS: Hematologic findings and bone marrow activity in patients with HbH/b-thal trait were consistent with the modified globin chain imbalance and hemoglobin synthesis expected from interaction of HbH disease with heterozygous b-thalassemia, although this rare complex genotype may elude diagnosis based on hematology alone. Significantly higher red cell 2,3-DPG levels were an unexpected finding, and the consequent increase in oxygen release capability resulted in a compensated functional anemia relative to hemoglobin levels.


Assuntos
Globinas/genética , Reticulócitos/metabolismo , Talassemia alfa/sangue , Talassemia alfa/patologia , Adolescente , Adulto , Anemia/sangue , Anemia/etiologia , Medula Óssea/patologia , Criança , Pré-Escolar , Saúde da Família , Feminino , Genótipo , Globinas/fisiologia , Heterozigoto , Humanos , Lactente , Masculino , Fenótipo , Talassemia alfa/genética , Talassemia beta/sangue , Talassemia beta/genética , Talassemia beta/patologia
19.
Br J Haematol ; 111(3): 915-23, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11122156

RESUMO

Haemoglobin H (Hb H) disease is the severest form of alpha-thalassaemia compatible with post-natal life and occurs when alpha-thalassaemia mutations interact to reduce alpha-globin synthesis to levels approximately equivalent to the output of a single alpha-globin gene. Hb H disease has variable clinical expression, mainly related to underlying genotypes. The spectrum of alpha-thalassaemia determinants in Greece appears greater than in any other population studied and, in 75 Greek Hb H disease patients, we found 12 alpha-thalassaemia mutations interacting to produce 15 Hb H disease genotypes. Evaluation of haematological, biochemical and clinical findings, and correlation with genotypes, defined genetic predictors of disease severity and factors involved in disease progression. In accordance with previous reports, patients with non-deletion alpha-thalassaemia mutations had more severe clinical expression. Additionally, we found that all patients with the most severe phenotypes had alpha-thalassaemic globin variants. Phenotypic severity was not simply related to the degree of alpha-globin deficiency: high Hb H levels were found to exacerbate anaemia by negatively influencing tissue oxygenation, and both Hb H and alpha-thalassaemic haemoglobin variants appear to reduce red cell survival within the bone marrow and circulation. Together with the long-term follow-up in many patients, this report provides comprehensive information for management of Hb H disease and appropriate family counselling.


Assuntos
Talassemia alfa/genética , Adulto , Transfusão de Sangue , Criança , Seguimentos , Deleção de Genes , Aconselhamento Genético , Genótipo , Grécia , Hemoglobina H/análise , Hemoglobinas/análise , Humanos , Mutação , Fenótipo , Talassemia alfa/sangue , Talassemia alfa/terapia
20.
Blood Cells Mol Dis ; 26(4): 276-84, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11042028

RESUMO

Clinical phenotypes associated with abnormal globin chain biosynthesis may result in thalassemia (deficient quantity) or hemolytic anemia (abnormal hemoglobins). However, the phenotypic expression of hyperunstable hemoglobin variants often includes features of thalassemia, along with variable peripheral hemolysis. Hemoglobinopathies caused by highly unstable beta-chain variants have a dominant thalassemia-like phenotype, in which carriers have a clinical expression of thalassemia intermedia, but highly unstable alpha-globin variants are usually only phenotypically apparent when they interact with other alpha-thalassemia mutations. In a child with clinical and hematological features consistent with beta-thalassemia intermedia, DNA analysis excluded any beta-globin gene mutations but characterized a novel deletion cd37(C2)Pro>0 (Hb Heraklion) in the alpha1 globin gene, in trans to a common Mediterranean nondeletion alpha-thalassemia mutation (alpha(Hph)alpha). The deletion of proline at alpha37(C2) is predicted to result in severe instability of the variant hemoglobin, which on interaction with a synthesis-deficient alpha-thalassemia mutation causes a relatively severe dyserythropoietic anemia, representing an alternative phenotype associated with highly unstable alpha-chain variants. Hb Heraklion is the fourth highly unstable alpha-globin variant that we have observed in patients from Greece and Albania. Two variants involve the alpha2-globin gene: Hb Agrinio (alpha29(B10)Leu>Pro) and Hb Adana (alpha59(E8)Gly>Asp), and two the alpha1-gene: Hb Aghia Sophia (alpha62(E11)Val>0) and (Hb Heraklion a37(C2)Pro>0). Each has been observed on interaction with a different alpha-thalassemia mutation and the phenotypes associated with these highly unstable alpha-variants are presented.


Assuntos
Globinas/genética , Hemoglobinas Anormais/genética , Talassemia beta/genética , Adolescente , Adulto , Sequência de Bases , Criança , DNA/química , DNA/genética , Análise Mutacional de DNA , Globinas/química , Hemoglobinas Anormais/química , Humanos , Masculino , Modelos Moleculares , Mutação , Fenótipo , Deleção de Sequência , Homologia de Sequência do Ácido Nucleico , Talassemia beta/patologia
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