Clinical impact of somatic mosaicism in cases with small supernumerary marker chromosomes.

Somatic mosaicism is present in slightly more than 50% of small supernumerary marker chromosome (sSMC) carriers. Interestingly, non-acrocentric derived sSMC show mosaicism much more frequently than acrocentric ones. sSMC can be present in different mosaic rates, which may go below 5% of the studied cells. Also cryptic mosaicism can be present and mosaics may be differently expressed in different tissues of the body. Even though in the overwhelming majority of the cases somatic sSMC mosaicism has no direct clinical effect, there are also cases with altered clinical outcomes due to mosaicism. Also clinically important is the fact that a de novo sSMC, even present in mosaic, may be a hint of uniparental disomy (UPD). As it is under discussion to possibly replace standard karyotyping by methods like array-CGH, the impracticality of the latter to detect low-level sSMC mosaics and/or UPD has to be considered as well. Overall, sSMC mosaicism has to be studied carefully in each individual case, as it can be extremely informative and of importance, especially for prenatal genetic counseling.

First report of a small supernumerary der(8;14) marker chromosome.

Small supernumerary marker chromosomes (sSMC) are structurally abnormal chromosomes, generally equal in size or smaller than a chromosome 20 of the same metaphase spread. Most of them are unexpectedly detected in routine karyotype analyses, and it is usually not easy to correlate them with a specific clinical picture. A small group of sSMCs is derived from more than one chromosome, called complex sSMCs. Here, we report on a patient with a de novo complex sSMC, derived from chromosomes 8 and 14. Banding karyotype analysis, multiplex ligation-dependent probe amplification (MLPA), single nucleotide polymorphism (SNP)-based array, and fluorescence in situ hybridization (FISH) were performed to investigate its origin. Array and FISH analyses revealed a der(14)t(8;14)(p23.2;q22.1)dn. The propositus presents some clinical features commonly found in patients with partial duplication or triplication of 8p and 14q. This is the first report describing a patient with a congenital der(14)t(8;14)(p23.2;q22.1)dn sSMC.

Tetrasomy 9p mosaicism associated with a normal phenotype in two cases.

Tetrasomy 9p is a rare chromosomal syndrome and about 30% of known cases exhibit mosaicism. Approximately 50 of the reported cases with tetrasomy 9p mosaicism show a characteristic facial appearance, growth failure, and developmental delay. However, 3 patients with mosaicism for isochromosome 9p and a normal phenotype have also been reported. We report 2 additional cases of clinically normal young females with tetrasomy 9p mosaicism, one of whom also exhibited X chromosome aneuploidy mosaicism leading to an overall of 6 different cell lines. STR analysis performed on this complex mosaic case indicated that the extra isochromosome was of maternal origin while the X chromosome aneuploidy was of paternal origin, indicating a postzygotic event.

Is there a yet unreported unbalanced chromosomal abnormality without phenotypic consequences in proximal 4p?

Unbalanced chromosomal abnormalities (UBCA) are reported for >50 euchromatic regions of almost all human autosomes. UBCA are comprised of a few megabases of DNA, and carriers are in many cases clinically healthy. Here we report on a partial trisomy of chromosome 4 of the centromere-near region of the short arm of chromosome 4 present as a small supernumerary marker chromosome (sSMC). The sSMC was present in >70% of amnion cells and in 60% of placenta. Further delineation of the size of the duplicated region was done by molecular cytogenetics and array comparative genomic hybridization. Even though the sSMC lead to a partial trisomy of ~9 megabase pairs, a healthy child was born, developing normally at 1 year of age. No comparable cases are available in the literature. Thus, we discuss here the possibility of having found a yet unrecognized chromosomal region subject to UBCA.

Constitutional chromosome rearrangements that mimic the 2017 world health organization "acute myeloid leukemia with recurrent genetic abnormalities": A study of three cases and review of the literature.

OBJECTIVES: To identify and characterize constitutional chromosomal rearrangements that mimic recurrent genetic abnormalities in acute myeloid leukemia (AML). METHODS: Bone marrow and blood chromosome studies were reviewed to identify constitutional rearrangements that resemble those designated by the 2017 revised World Health Organization (WHO) "AML with recurrent genetic abnormalities". Mate-pair sequencing (MPseq) was performed on cases with constitutional chromosome mimics of recurrent AML abnormalities to further define the rearrangement breakpoints. RESULTS: Three cases with constitutional rearrangements were identified, including t(6;9)(p23;q34), inv(16)(p13.1q22), and t(9;22)(q34.1;q12.2). Two cases were bone marrow specimens being evaluated for hematologic neoplasms, while one case was a blood specimen being evaluated for primary ovarian insufficiency. MPseq provided high-resolution and precise rearrangement breakpoints, and resolved the atypical FISH results generated with each rearrangement. CONCLUSIONS: Our findings illustrate that constitutional rearrangements can mimic recurrent genetic abnormalities observed in AML, and we emphasize the importance of correlating genetic data with clinical and hematopathologic information.

Use of recombinant activated factor VII for acute bleeding episodes in acquired hemophilia: final analysis from the Hemostasis and Thrombosis Research Society Registry acquired hemophilia study.

The Hemostasis and Thrombosis Research Society Registry was used to monitor the postapproval use and safety of recombinant activated factor VII (rFVIIa). The objective of this article is to evaluate the data from the Hemostasis and Thrombosis Research Society Registry related to rFVIIa-treated bleeding episodes in patients with acquired hemophilia. For each rFVIIa-treated bleeding episode, the initial dose, total dose, average infused dose, number of doses, and treatment duration were calculated. Efficacy was assessed on a three-point scale. Out of the 166 registered patients with acquired hemophilia, 110 patients were treated for 237 bleeding episodes (139 rFVIIa treated); the majority (70%) were in patients older than 60 years. The most frequently reported bleeding locations were subcutaneous (40%) and mucosal (32%). Subcutaneous bleeding episodes were more commonly reported in women (55% vs. 40% men) and white patients (44 vs. 27% black). Of the 139 rFVIIa-treated bleeding episodes, rFVIIa was used as first-line treatment in 127 bleeding episodes. The median initial dose was 90 µg/kg; the median total dose per episode was 333.5 µg/kg. Physician-rated efficacy of rFVIIa for each bleeding episode was reported as 'bleeding stopped' in 85% of bleeding episodes, 'bleeding slowed' in 11% of bleeding episodes, 'no improvement' in 4% of bleeding episodes, and was not documented in 1 bleeding episode. One thromboembolic event was reported; transient neurologic symptoms were reported in a 31-year-old postpartum patient after 110 doses of rFVIIa. Adequate hemostasis was provided for most rFVIIa-treated bleeding episodes at doses largely conforming to the package insert. No major safety concerns were reported.

Assessment of acquired hemophilia patient demographics in the United States: the Hemostasis and Thrombosis Research Society Registry.

The Hemostasis and Thrombosis Research Society (HTRS) Registry was used to monitor the postapproval use of recombinant factor VIIa. The objective of this manuscript is to provide key insights on the demographics of patients with acquired hemophilia in the HTRS Registry. Acquired hemophilia patient registration in HTRS captured age; sex; comorbidities and predisposing conditions; first bleeding location; laboratory parameters; exposure to blood products, factor, and bypassing agents; and initiation of immune suppression/tolerance therapy. Overall, 166 patients with acquired hemophilia were registered in HTRS (83 women, 73 men, median age 70 years); the majority were non-Hispanic whites (61.4%). The most common comorbidities were autoimmune disease (28.4%) and malignancy (14.5%). The most common first site of bleeding was subcutaneous (27.1%); this was more common in whites (29.1%) than blacks (12.5%) and in non-Hispanics (26.4%) than Hispanics (11.8%). Blood product exposure was reported for 33.1% of patients; the most commonly reported product was packed red blood cells (28%). Of the 57 patients with outcome data available for immune tolerance therapy, 26 patients (46%) reported successful treatment, 13 reported unsuccessful treatment (23%), and 18 (32%) were receiving active treatment at the time of registration. The HTRS Registry final analysis provides the only current comprehensive look at acquired hemophilia in the US population, including details on underlying autoimmune diseases and malignancies. Pertinent to recognition and diagnosis of the disease, subcutaneous bleeding as a presenting bleeding symptom was more common in white and non-Hispanic individuals.

[Effect of phenothiazine derivative on adrenal cortex response of sheep to repeated emotional stress]. / Wplyw pochodnej fenotiazyny na reakcje kory nadnerczy owiec w czasie wielokrotnego stresu emocjonalnego.

The study was aimed at the evaluation of propiopromazine (Combelen, Bayer), a derivative of phenothiazine, as an agent lowering in sheep the response to stress. The stress of emotional origin was induced in sheep by the isolation from herd lasting 1 hour. The isolation experiments were repeated 6 times on the same group of sheep, first three isolations (1-3) in daily intervals and next three (4-6) in weekly intervals. Propiopromazine was administered before each isolation experiment. The reaction of sheep to the isolation stress was weaker after propiopromazine administration. This was suggested by smaller increase in blood serum cortisol and glucose levels when compared to sheep subjected to isolation but not receiving the drug. Such effect was especially conspicuous during the course of the first isolation experiment; during the next experiments the difference concerning the reaction to stress between the sheep isolated from the herd receiving and not receiving the drug was gradually diminishing. It was shown in addition that propiopromazine administration to the sheep not subjected to stress caused an increase in cortisol level by 125 per cent and that in glucose level by 35 per cent. These results suggest that propiopromazine administration protects the organism against the effects of emotional stress only partially. Moreover, the effect of its administration gradually weakens with repeating of the stress inducing experiment, and propiopromazine itself may act as a stress inducing factor. It seems therefore that the use of propiopromazine and similar compounds as anti-stress agents may be questionable.

Targeted next-generation resequencing of f5 gene identifies novel multiple variants pattern in severe hereditary factor v deficiency.

The present study investigated the genetic defects underlying severe Factor V deficiency in a 26-year-old Columbian (South America) female and her immediate family (both parents and newborn child) by next generation sequencing (NGS) of the entire F5 gene locus. Five mutations in the coding sequence of F5, including three missense single-nucleotide variants (R2102H, R513K, D107H) and two synonymous variants (A135A , S184S), were identified and confirmed by the Sanger sequencing in the investigated proband (homozygote for all detected mutations), her parents, and her newborn child (all heterozygotic carriers for identified mutations). Each of the three missense variants was previously associated with separate phenotypes, including Factor V deficiency (R2102H), thrombosis (R513K) and frequent miscarriages (D107H). In addition, at least 75 additional single-nucleotide variants (including six novels) were identified in untranslated region of F5.

Degradation of aflatoxin by Aspergillus flavus.

Aflatoxin degradative activity was demonstrated in 6- to 12-d-old intact mycelium and cell-free extracts of Aspergillus flavus. The addition of cycloheximide, SKF 525-A or metyrapone to cultures of A. flavus prevented subsequent degradation of the aflatoxins, while in cell-free extracts degradation was inhibited by SKF 525-A, metyrapone and cytochrome c but not by KCN. In cell-free extracts, aflatoxin degradation was enhanced by NADPH and NaIO4. The results suggest the involvement of cytochrome P-450 monooxygenases in the aflatoxin degradative activity of A. flavus.