RESUMO
Tangier disease is an autosomal recessive disorder caused by mutations in the ABCA1 gene and characterized by the accumulation of cholesteryl ester in various tissues and a near absence of high-density lipoprotein. The subject in this investigation was a 36-year-old Italian man with Tangier disease. He and his wife had come to the In Vitro Fertilization Unit, Pesaro Hospital (Azienda Ospedaliera Ospedali Riuniti Marche Nord) seeking help regarding fertility issues. The man was diagnosed with severe oligoasthenoteratozoospermia. Testosterone is the sex hormone necessary for spermatogenesis and cholesterol is its precursor; hence, we hypothesized that the characteristic cholesterol deficiency in Tangier disease patients could compromise their fertility. The aim of the study was to therefore to determine if there is an association between Tangier disease and male infertility. After excluding viral, infectious, genetic and anatomical causes of the subject's oligoasthenoteratozoospermia, we performed a hormonal analysis to verify our hypothesis. The patient was found to be negative for frequent bacteria and viruses. The subject showed a normal male karyotype and tested negative for Yq microdeletions and Cystic Fibrosis Transmembrane Conductance Regulator gene mutations. A complete urological examination was performed, and primary hypogonadism was also excluded. Conversely, hormonal analyses showed that the subject had a high level of follicle stimulating hormone and luteinizing hormone, low total testosterone and a significant decline in inhibin B. We believe that the abnormally low cholesterol levels typically found in subjects with Tangier disease may result in a reduced testosterone production which in turn could affect the hormonal axis responsible for spermatogenesis leading to a defective maturation of spermatozoa.
Assuntos
Colesterol/genética , Infertilidade Masculina/genética , Doença de Tangier/genética , Testosterona/biossíntese , Transportador 1 de Cassete de Ligação de ATP/genética , Adulto , Colesterol/deficiência , Ésteres do Colesterol/genética , Ésteres do Colesterol/metabolismo , Humanos , Infertilidade Masculina/complicações , Infertilidade Masculina/fisiopatologia , Masculino , Mutação , Oligospermia/complicações , Oligospermia/genética , Oligospermia/fisiopatologia , Espermatogênese/genética , Doença de Tangier/complicações , Doença de Tangier/fisiopatologiaRESUMO
The molecular pathogenesis of primary mielofibrosis (PMF) is still largely unknown. Recently, single-nucleotide polymorphism arrays (SNP-A) allowed for genome-wide profiling of copy-number alterations and acquired uniparental disomy (aUPD) at high-resolution. In this study we analyzed 20 PMF patients using the Genome-Wide Human SNP Array 6.0 in order to identify novel recurrent genomic abnormalities. We observed a complex karyotype in all cases, detecting all the previously reported lesions (del(5q), del(20q), del(13q), +8, aUPD at 9p24 and abnormalities on chromosome 1). In addition, we identified several novel cryptic lesions. In particular, we found a recurrent alteration involving cytoband 20p13 in 55% of patients. We defined a minimal affected region (MAR), an amplification of 9,911 base-pair (bp) overlapping the SIRPB1 gene locus. Noteworthy, by extending the analysis to the adjacent areas, the cytoband was overall affected in 95% of cases. Remarkably, these results were confirmed by real-time PCR and validated in silico in a large independent series of myeloproliferative diseases. Finally, by immunohistochemistry we found that SIRPB1 was over-expressed in the bone marrow of PMF patients carrying 20p13 amplification. In conclusion, we identified a novel highly recurrent genomic lesion in PMF patients, which definitely warrant further functional and clinical characterization.
Assuntos
Cromossomos Humanos Par 20/genética , Amplificação de Genes/genética , Cariotipagem , Análise de Sequência com Séries de Oligonucleotídeos , Polimorfismo de Nucleotídeo Único/genética , Mielofibrose Primária/genética , Idoso , Estudos de Coortes , DNA/genética , Variações do Número de Cópias de DNA/genética , Feminino , Genômica , Humanos , Perda de Heterozigosidade/genética , Masculino , Mielofibrose Primária/metabolismo , Receptores de Superfície Celular/metabolismo , Taq Polimerase/metabolismo , Dissomia Uniparental/genéticaRESUMO
Cell storage in liquid nitrogen (LN) offers the most secure method of cell preservation even if cryopreserved cells are exposed to natural background of ionising radiation (IR). A lot of experiments have demonstrated that IR can induce damages in living cells, but only a little information regarding the response of cryopreserved cells is available. To investigate the effect of IR on frozen and unfrozen cells, peripheral blood mononuclear cells were directly irradiated at room temperature, then immediately frozen, or frozen and then irradiated in LN with different doses of gamma rays. After thawing, cells were incubated and death fraction was evaluated at different time points. Interestingly, the percentages of dead cells induced by IR gradually increased with both dose radiation and incubation time and were significantly lower for cells irradiated at -196°C than those irradiated at room temperature.