Neonatal electroencephalography (EEG) presents a challenge due to its difficult interpretation that differs significantly from interpretation in older children and adolescents. Also, from the technological point of view, itis more difficult to perform and is not a standard procedure in all neonatal intensive care units (NICUs). During recent years, long-term cerebral function monitoring by the means of amplitude-integrated EEG (aEEG) has become popular in NICUs because it is easy to apply, allows real-time interpretation by the neonatologist treating the newborn, and has predictive value for outcome. On the other side, to record conventional EEG (cEEG), which is still considered the gold standard of neonatal EEG, the EEG technician should not only be well trained in performing neonatal EEG but alsohas to adapt to suboptimal working conditions. These issues need to be understood when approaching the neonatal cEEG in NICU and the main structure of the article is dedicated to this technique. The authors discuss the benefits of the digitalization and its positive effects on the improvement of NICU recording. The technical aspects as well as the standards for cEEG recording are described, and a section is dedicated to possible artifacts. Thereafter, alternative and concomitant use of aEEG and its benefits are briefly discussed. At the end there is a section that presents a review of ourown cEEG and aEEG recordings that were chosen as the most frequently encountered patterns according to Consensus statement on the use of EEG in theintensive care unit.
COBISS.SI-ID: 28718297
Genetic causes of premature ovarian failure (POF) comprise less than one-third of all cases, among them X chromosome abnormalities, mutations and polymorphisms in some genes. The frequency of X-chromosome mosaicism in women with sporadic POF has been found to range between 3 and 10%, whereas the prevalence of POF in carriers of the FMR1 premutation is estimated to range between 13 and 25%. We report two successful pregnancy outcomes after in vitrofertilization-embryo transfer with donated oocytes in a woman with severePOF of a complex genetic origin. Chromosome analysis, fluorescence in situ hybridization on cultured peripheral blood lymphocytes and buccal mucosalcells, and molecular genetic studies, using autosomal, Y-chromosomal polymorphic microsatellite or short tandem repeat markers and CGG repeats in the FMR1 gene, were performed. FMR1 premutation, sex chromosome mosaicism and blood lymphocyte microchimerism were found. Assisted reproduction techniques can be safely used in POF women after a thorough clinical evaluation and genetic counselling.
COBISS.SI-ID: 27118041
Low-level X chromosome mosaicism and its clinical relevance are still under debate. It could be interpreted as a technical artefact, genuine mosaicism or as being age-related. This study evaluated the contribution of X chromosome mosaicism in phenotypically normal women with sporadic premature ovarian failure (POF). During 1999-2008, 114 patients with POF and 64 age matched controls were karyotyped. Thirteen patients (11.4%) had true X chromosome mosaicism ()10% of aneuploid cells) and 12 had (10.5%) low-level X-mosaicism (between 6-10% of aneuploid cells). The mean age of women with true and low-level mosaicism was 26.0+/-5.65 years and 35.92+/-3.87 years, respectively(P(0.001). In the control group the incidence of cells with an abnormal number of X chromosomes was 1-3%. The results have practical implications for genetic counselling and fertility treatment. To search and confirm the low-level mosaicism, a higher number of metaphases should be analysed or additional fluorescence in-situ hybridization analysis must be performed. Although peripheral blood does not reflect the situation in ovariantissue well, it is presumed that there are different aetiological causes for true and low-level X chromosome mosaicism. The possible causes and reproductive significance of low-level X chromosome mosaicism are discussed. Xchromosome abnormalities are usually associated with abnormal sexual development and reproductive performance, such as amenorrhoea, infertility, recurrent abortions and premature ovarian failure. X chromosome mosaicism is the presence of two populations of cells in the body. Some cells have two X chromosomes while others have only one X chromosome. Low-level X chromosome mosaicism (less than 10% of cells have one X chromosome) and its clinical relevance are still under debate. It could be interpreted as a technical artefact, genuine mosaicism or as being age-related. (Abs. trunc. at 2000 ch.)
COBISS.SI-ID: 28233945