Nijmegen breakage syndrome (NBS)

Nijmegen breakage syndrome (NBS) is a rare autosomal recessive syndrome of chromosomal instability mainly characterized by microcephaly at birth, combined immunodeficiency and predisposition to malignancies. Due to a founder mutation in the underlying NBN gene (c.657_661del5) the disease is encountered most frequently among Slavic populations. The principal clinical manifestations of the syndrome are: microcephaly, present at birth and progressive with age, dysmorphic facial features, mild growth retardation, mild-to-moderate intellectual disability, and, in females, hypergonadotropic hypogonadism. Combined cellular and humoral immunodeficiency with recurrent sinopulmonary infections, a strong predisposition to develop malignancies (predominantly of lymphoid origin) and radiosensitivity are other integral manifestations of the syndrome. The NBN gene codes for nibrin which, as part of a DNA repair complex, plays a critical nuclear role wherever double-stranded DNA ends occur, either physiologically or as a result of mutagenic exposure. Laboratory findings include: (1) spontaneous chromosomal breakage in peripheral T lymphocytes with rearrangements preferentially involving chromosomes 7 and 14, (2) sensitivity to ionizing radiation or radiomimetics as demonstrated in vitro by cytogenetic methods or by colony survival assay, (3) radioresistant DNA synthesis, (4) biallelic hypomorphic mutations in the NBN gene, and (5) absence of full-length nibrin protein. Microcephaly and immunodeficiency are common to DNA ligase IV deficiency (LIG4 syndrome) and severe combined immunodeficiency with microcephaly, growth retardation, and sensitivity to ionizing radiation due to NHEJ1 deficiency (NHEJ1 syndrome). In fact, NBS was most commonly confused with Fanconi anaemia and LIG4 syndrome. Genetic counselling should inform parents of an affected child of the 25% risk for further children to be affected. Prenatal molecular genetic diagnosis is possible if disease-causing mutations in both alleles of the NBN gene are known. No specific therapy is available for NBS, however, hematopoietic stem cell transplantation may be one option for some patients. Prognosis is generally poor due to the extremely high rate of malignancies

Immortalization of T-cells is accompanied by gradual changes in CpG methylation resulting in a profile resembling a subset of T-cell leukemias

We have previously described gene expression changes during spontaneous immortalization of T-cells, thereby identifying cellular processes important for cell growth crisis escape and unlimited proliferation. Here, we analyze the same model to investigate the role of genome-wide methylation in the immortalization process at different time points pre-crisis and post-crisis using high-resolution arrays. We show that over time in culture there is an overall accumulation of methylation alterations, with preferential increased methylation close to transcription start sites (TSSs), islands, and shore regions. Methylation and gene expression alterations did not correlate for the majority of genes, but for the fraction that correlated, gain of methylation close to TSS was associated with decreased gene expression. Interestingly, the pattern of CpG site methylation observed in immortal T-cell cultures was similar to clinical T-cell acute lymphoblastic leukemia (T-ALL) samples classified as CpG island methylator phenotype positive. These sites were highly overrepresented by polycomb target genes and involved in developmental, cell adhesion, and cell signaling processes. The presence of non-random methylation events in in vitro immortalized T-cell cultures and diagnostic T-ALL samples indicates altered methylation of CpG sites with a possible role in malignant hematopoiesis

Spectrum of JAG1 gene mutations in Polish patients with Alagille syndrome

Alagille syndrome (ALGS) is an autosomal dominant disorder characterized by developmental abnormalities in several organs including the liver, heart, eyes, vertebrae, kidneys, and face. The majority (90-94 %) of ALGS cases are caused by mutations in the JAG1 (JAGGED1) gene, and in a small percent of patients (∼1 %) mutations in the NOTCH2 gene have been described. Both genes are involved in the Notch signaling pathway. To date, over 440 different JAG1 gene mutations and ten NOTCH2 mutations have been identified in ALGS patients. The present study was conducted on a group of 35 Polish ALGS patients and revealed JAG1 gene mutations in 26 of them. Twenty-three different mutations were detected including 13 novel point mutations and six large deletions affecting the JAG1 gene. Review of all mutations identified to date in individuals from Poland allowed us to propose an effective diagnostic strategy based on the mutations identified in the reported patients of Polish descent. However, the distribution of mutations seen in this cohort was not substantively different than the mutation distribution in other reported populations

Impaired p53-Mediated DNA Damage Response Contributes to Microcephaly in Nijmegen Breakage Syndrome Patient-Derived Cerebral Organoids

Nijmegen Breakage Syndrome (NBS) is a rare autosomal recessive genetic disorder caused by mutations within nibrin (NBN), a DNA damage repair protein. Hallmarks of NBS include chromosomal instability and clinical manifestations such as growth retardation, immunodeficiency, and progressive microcephaly. We employed induced pluripotent stem cell-derived cerebral organoids from two NBS patients to study the etiology of microcephaly. We show that NBS organoids carrying the homozygous 657del5 NBN mutation are significantly smaller with disrupted cyto-architecture. The organoids exhibit premature differentiation, and Neuronatin (NNAT) over-expression. Furthermore, pathways related to DNA damage response and cell cycle are differentially regulated compared to controls. After exposure to bleomycin, NBS organoids undergo delayed p53-mediated DNA damage response and aberrant trans-synaptic signaling, which ultimately leads to neuronal apoptosis. Our data provide insights into how mutations within NBN alters neurogenesis in NBS patients, thus providing a proof of concept that cerebral organoids are a valuable tool for studying DNA damage-related disorders

Continuity in language: styles and registers in literary and non-literary discourse

Praca recenzowana / peer-reviewed paperIntroduction: "Linguistic diversity captured with the terms style and register is of interest to literary theory and to linguistic theory, as both are concerned with how individuals and the multiple social groups and networks that they can simultaneously be members of articulate themselves and how they distinguish themselves from others, the reasons that speakers/writers may have for their choice of linguistic forms, the ways in which these linguistic forms can be creatively exploited in particular contexts as well as with the effects that the choices and departures from norms or conventions of use may have on the hearers/readers. Among the issues of common interest to literary and linguistic theory are the formal, cultural, historical, axiological, moral, ideological, social, psychological, hermeneutic, and other aspects of the structure, production and perception of language. These aspects are traditionally studied in relation to general concepts of convention and creativity, literalness and fictionality, objectivity and subjectivity, politeness and power, consensus and conflict, class and stigma, affect, personal identity and allegiance, and many others."(...

The effects of 3-year growth hormone treatment and body composition in Polish patients with Silver-Russell syndrome

Introduction: Silver-Russell syndrome (SRS) is characterized by clinical and genetic heterogeneity. SRS is the only disease entity associated with (epi)genetic abnormalities of 2 different chromosomes: 7 and 11. In SRS, the 2 most frequent molecular abnormalities are hypomethylation (loss of methylation) of region H19/IGF2:IG-DMR on chromosome 11p15.5 (11p15 LOM) and maternal uniparental disomy of chromosome 7 (upd(7)mat). Therapy with recombinant human growth hormone (rhGH) is implemented to increase body height in children with SRS. The effect of the administered rhGH on height, weight, body mass index (BMI), body composition, and height velocity in patients with SRS during 3 years of rhGH therapy was analysed. Material and methods: 31 SRS patients (23 with 11p15 LOM, 8 with upd(7)mat) and 16 patients small for gestational age (SGA) as a control group were diagnosed and followed up in The Children’s Memorial Health Institute. Patients were eligible for the 2 Polish rhGH treatment programmes [for patients with SGA or with growth hormone deficiency (GHD)]. Anthropometric parameters were collected in all patients. Body composition using bioelectrical impedance was measured in 13 SRS and 14 SGA patients. Results: Height, weight, and weight for height (SDS) at baseline of rhGH therapy were lower in SRS patients than in the SGA control group: –3.3 ± 1.2 vs. -2.6 ± 06 (p = 0.012), –2.5 vs. -1.9 (p = 0.037), –1.7 vs. –1.1 (p = 0.038), respectively. Height SDS was increased from –3.3 ± 1.2 to –1.8 ± 1.0 and from –2.6 ± 0.6 to –1.3 ± 0.7 in the SRS and SGA groups, respectively. Patients with 11p15 LOM and upd(7)mat achieved similar height, 127.0 ± 15.7 vs. 128.9 ± 21.6 cm, and –2.0 ± 1.3 vs. –1.7 ± 1.0 SDS, respectively. Fat mass percentage decreased in SRS patients from 4.2% to 3.0% (p < 0.05) and in SGA patients from 7.6% to 6.6% (p < 0.05). Conclusions: Growth hormone therapy has a positive influence on the growth of SRS patients. Regardless of molecular abnormality type (11p15 LOM vs. upd(7)mat), height velocity was similar in SRS patients during 3 years of rhGH therapy

Transient Elastography for Detection of Liver Fibrosis in Children With Autosomal Recessive Polycystic Kidney Disease

Introduction: Congenital hepatic fibrosis (CHF) is invariably present in all patients with autosomal recessive polycystic kidney disease (ARPKD) but is usually clinically asymptomatic. The portal hypertension in the course of CHF develops and progresses over time, so an early detection of liver fibrosis remains crucial.Aim: The aim of the study was to evaluate a predictive value of transient elastography for evaluating liver disease progress in pediatric ARPKD patients.Material and Methods: The study group encompassed 21 pediatric patients with ARPKD and 20 healthy children (control group) from The Children's Memorial Health Institute in Warsaw, Poland. Liver fibrosis was determined by assessing the liver stiffness (LS) with transient elastography (FibroScan®, FS) using size-appropriate probes. In ARPKD group the laboratory findings, results of an abdominal ultrasound examination, and an endoscopic gastroduodenoscopy were also analyzed.Results: Compared with healthy controls, patients with ARPKD had significantly increased median LS values (22 vs. 4.25 kPa, p < 0.0001). Based on FS results, ARPKD group was divided into two subgroups: patients (n = 5) with LS results suggestive of no fibrosis or minimal fibrosis (LS < 6.9 kPa, METAVIR fibrosis stage 0–1) and patients (n = 16) with LS results suggestive of at least significant liver fibrosis (LS ≥ 6.9 kPa, METAVIR fibrosis stage 2–4). In the first subgroup (no fibrosis or minimal fibrosis), all patients had no signs of portal hypertension. In the subgroup with at least significant liver fibrosis, splenomegaly was observed in 87.5% of patients and thrombocytopenia in 69% of patients. An endoscopic gastroduodenoscopy was performed in 15 out of 21 ARPKD patients, nine patients (60%) had esophageal varices. All of these patients had LS results suggestive of at least significant liver fibrosis.Conclusions: TE by FibroScan can be used as an additional method for evaluating liver disease progress in pediatric ARPKD patients

Ocena prawdopodobieństwa urodzenia dziecka z niezrównoważonym kariotypem oraz ryzyka wystąpienia rożnych patologii ciąży w rodzinach nosicieli translokacji chromosomowych wzajemnych angażujących chromosom 7

Introduction: Carriership of reciprocal chromosomal translocation (RCT) may be the reason the occurrence of congenital malformations in the offspring, early neonatal death, stillbirth, and recurrent miscarriages due to unbalanced karyotype of gametes. The probability rate for individual categories of unfavorable outcomes depends on the kind of chromosome involved and is individually variable. Objectives: The aim of study was to estimate the probability rates for unbalanced offspring and to evaluate the risk for different categories of unfavorable pregnancy outcomes, depending on the size of chromosomal segment with differentiation between maternal/paternal origin of the reciprocal chromosomal translocations involving chromosome 7p (RCT-7p) and 7q (RCT-7q). In addition, the use of the obtained results has been illustrated by the example of a family with unique RCT t(7;9)(p21.3,p23). Material and methods: Empirical and cytogenetic data on 341 pregnancies and offspring of 133 carriers were collected from 69 pedigrees of carriers of RCT-7p and RCT-7q at risk for a single 7 segment imbalance. The probability rates of particular form of pregnancy pathology have been calculated according to the method of Stengel-Rutkowski and Stene, including all forms of meiotic segregation and their survival rates after fertilization to term childbirth. Results: The probability rates for unbalanced offspring for carriers of RCT-7p after 2:2 disjunction and adjacent-1 segregation were calculated as 5.5%±2.2% (6/108); for maternal (MAT) and paternal (PAT) carriers were aboutCel pracy: Celem pracy było opracowanie wskaźników prawdopodobieństwa urodzenia dziecka z niezrównoważonym kariotypem oraz wskaźników ryzyka różnych patologii ciąży w rodzinach nosicieli translokacji chromosomowych wzajemnych angażujących segmenty chromosomu 7 (TCW-7), w zależności od długości pojedynczych segmentów krótkich (TCW-7p) i długich (TCW-7q) ramion chromosomu 7, z uwzględnieniem rodzicielskiego pochodzenia nosicielstwa. Na przykładzie rodziny z nosicielstwem unikatowej t(7;9)(p21.3;p23) zaprezentowano, w jaki sposób praktycznie można wykorzystać uzyskane wskaźniki udzielając porady genetycznej. Materiał i metody: Analizę segregacyjną przeprowadzono w grupie 69 rodowodów nosicieli TCW-7 zawierających dane kliniczne i cytogenetyczne 341 ciąż i urodzeń potomstwa w sześciu grupach oddzielnie w zależności od długości segmentu 7p i 7q wyznaczonej przez położenie punktu złamania TCW: 7p21→pter, 7p14…p15→pter, 7p11…p12…p13→pter oraz 7q33…q34…q35→qter, 7q32 →qter, 7q11…q21.. q22…q31→qter z uwzględnieniem rodzicielskiego pochodzenia TCW. Wyniki: Prawdopodobieństwo urodzenia dziecka z niezrównoważonym kariotypem w przypadku nosicielstwa TCW-7p wynosiło 5.5±2.2% (6/108) (w tym matczyne MAT