Hearing screening of school children in the Podkarpackie Voivodeship, Poland

IntroductionHearing screening is an important part of prevention. It allows early detection of hearing disorders, thus the treatment may begin early, and eliminates or minimises negative consequences. Children with hearing impairment often experience delayed speech development and cognitive abilities, which can result in learning disabilities and reduce school progress. Since 1999, the Institute of Physiology and Pathology of Hearing in Poland has provided a hearing screening program for school-age children in the country. The main aim of the program is the early detection of hearing disorders in children starting school, and increase in the awareness among parents of hearing problems.Materials and MethodsPure-tone air-conduction hearing thresholds were obtained at 0.5–8 kHz. The results of the hearing screening examination were regarded as positive if pure-tone thresholds were higher than 20 dB HL in one or both ears at one or more of the test frequencies. The audiometric results were supplemented by questionnaires completed by the parents. There were 8,091 first-grade children from the Podkarpackie Voivodeship enrolled in the program.ResultsBased on the audiogram, screening showed that hearing impairment was found in 1618 children (20% of the examined children).ConclusionOur study yielded a large group of children with hearing problems. We recommend that hearing screening in primary schools should be a routine procedure within a general framework of preventive pediatric health care

Hearing screening program in children from primary schools in Poland

Institute of Physiology and Pathology of Hearing, Warsaw, Poland, The 8th International Medical Congress for Students and Young Doctors, September 24-26, 2020Introduction. Hearing is one of our most socially important sensory organs , violations of which lead to improper perception of sound and the development of speech and, as a result, to a violation of human social functions. Critical is the early detection of hearing pathologies and, as a consequence, the introduction of appropriate therapy and rehabilitation. This gives us the opportunity to promptly and adequately respond and eliminate the emerging problems. Aim of the study. Analysis of hearing screening of primary school children in Poland Materials and methods. Hearing screening was conducted in a group of 290 children from two primary schools in Poland (Warsaw). Screening was performed using the Senses Examination Platform according to the audiometric procedure of hearing thresholds measurement. Positive result of HTL in screening was defined as equal or more than 25dB at least at one frequency at in either ear. Results. Positive results of hearing screening were obtained in 4.82% of tested children. All the tests were performed according to accepted standards. in case of 14 children additional tests were conducted. Bilateral hearing loss was diagnosed among 50% of children with hearing impairment. Conclusions. Obtained results confirmed the fact of a moderate amount of hearing impairment in school aged children. On the basis of the results we strongly recommend the implementation of hearing screening as a routine procedure in school health care

Evolutionary dynamics of cancer cell populations under immune selection pressure and optimal control of chemotherapy

Increasing experimental evidence suggests that epigenetic and microenvironmental factors play a key role in cancer progression. In this respect, it is now generally recognized that the immune system can act as an additional selective pressure, which modulates tumor development and leads, through cancer immunoediting, to the selection for resistance to immune effector mechanisms. This may have serious implications for the design of effective anti-cancer protocols. Motivated by these considerations, we present a mathematical model for the dynamics of cancer and immune cells under the effects of chemotherapy and immunity-boosters. Tumor cells are modeled as a population structured by a continuous phenotypic trait, that is related to the level of resistance to receptor-induced cell death triggered by effector lymphocytes. The level of resistance can vary over time due to the effects of epigenetic modifications. In the asymptotic regime of small epimutations, we highlight the ability of the model to reproduce cancer immunoediting. In an optimal control framework, we tackle the problem of designing effective anti-cancer protocols. The results obtained suggest that chemotherapeutic drugs characterized by high cytotoxic effects can be useful for treating tumors of large size. On the other hand, less cytotoxic chemotherapy in combination with immunity-boosters can be effective against tumors of smaller size. Taken together, these results support the development of therapeutic protocols relying on combinations of less cytotoxic agents and immune-boosters to fight cancer in the early stages. © EDP Sciences, 2014

Gene signature of the post-Chernobyl papillary thyroid cancer

Purpose: Following the nuclear accidents in Chernobyl and later in Fukushima, the nuclear community has been faced with important issues concerning how to search for and diagnose biological consequences of low-dose internal radiation contamination. Although after the Chernobyl accident an increase in childhood papillary thyroid cancer (PTC) was observed, it is still not clear whether the molecular biology of PTCs associated with low-dose radiation exposure differs from that of sporadic PTC. Methods: We investigated tissue samples from 65 children/young adults with PTC using DNA microarray (Affymetrix, Human Genome U133 2.0 Plus) with the aim of identifying molecular differences between radiation-induced (exposed to Chernobyl radiation, ECR) and sporadic PTC. All participants were resident in the same region so that confounding factors related to genetics or environment were minimized. Results: There were small but significant differences in the gene expression profiles between ECR and non-ECR PTC (global test, p < 0.01), with 300 differently expressed probe sets (p < 0.001) corresponding to 239 genes. Multifactorial analysis of variance showed that besides radiation exposure history, the BRAF mutation exhibited independent effects on the PTC expression profile; the histological subset and patient age at diagnosis had negligible effects. Ten genes (PPME1, HDAC11, SOCS7, CIC, THRA, ERBB2, PPP1R9A, HDGF, RAD51AP1, and CDK1) from the 19 investigated with quantitative RT-PCR were confirmed as being associated with radiation exposure in an independent, validation set of samples. Conclusion: Significant, but subtle, differences in gene expression in the post-Chernobyl PTC are associated with previous low-dose radiation exposure

Mathematical model of heterogeneous cancer growth with an autocrine signalling pathway

[[abstract]]Objectives Cancer is a complex biological occurrence which is difficult to describe clearly and explain its growth development. As such, novel concepts, such as of heterogeneity and signalling pathways, grow exponentially and many mathematical models accommodating the latest knowledge have been proposed. Here, we present a simple mathematical model that exhibits many characteristics of experimental data, using prostate carcinoma cell spheroids under treatment. Materials and methods We have modelled cancer as a two-subpopulation system, with one subpopulation representing a cancer stem cell state, and the other a normal cancer cell state. As a first approximation, these follow a logistical growth model with self and competing capacities, but they can transform into each other by using an autocrine signalling pathway. Results and conclusion By analysing regulation behaviour of each of the system parameters, we show that the model exhibits many characteristics of actual cancer growth curves. Features reproduced in this model include delayed phase of evolving cancer under 17AAG treatment, and bi-stable behaviour under treatment by irradiation. In addition, our interpretation of the system parameters corresponds well with known facts involving 17AAG treatment. This model may thus provide insight into some of the mechanisms behind cancer.[[incitationindex]]SCI[[booktype]]電子版[[booktype]]紙

Zeros and the functional equation of the quadrilateral zeta function

In this paper, we show that all real zeros of the bilateral Hurwitz zeta function $Z(s,a):=\zeta (s,a) + \zeta (s,1-a)$ with $1/4 \le a \le 1/2$ are on only the non-positive even integers exactly same as in the case of $(2^s-1) \zeta (s)$. We also prove that all real zeros of the bilateral periodic zeta function $P(s,a):={\rm{Li}}_s (e^{2\pi ia}) + {\rm{Li}}_s (e^{2\pi i(1-a)})$ with $1/4 \le a \le 1/2$ are on only the negative even integers just like $\zeta (s)$. Moreover, we show that all real zeros of the quadrilateral zeta function $Q(s,a):=Z(s,a) + P(s,a)$ with $1/4 \le a \le 1/2$ are on only the negative even integers. On the other hand, we prove that $Z(s,a)$, $P(s,a)$ and $Q(s,a)$ have at least one real zero in $(0,1)$ when $0<a<1/2$ is sufficiently small. The complex zeros of these zeta functions are also discussed when $1/4 \le a \le 1/2$ is rational or transcendental. As a corollary, we show that $Q(s,a)$ with rational $1/4 < a < 1/3$ or $1/3 < a < 1/2$ does not satisfy the analogue of the Riemann hypothesis even though $Q(s,a)$ satisfies the functional equation that appeared in Hamburger's or Hecke's theorem and all real zeros of $Q(s,a)$ are located at only the negative even integers again as in the case of $\zeta (s)$.Comment: 12 pages. We changed the title. Some typos are correcte

Częstość występowania mutacji somatycznych RAS w raku rdzeniastym tarczycy — analiza populacji polskiej

Introduction: Somatic RET mutations are detectable in two-thirds of sporadic cases of medullary thyroid cancer (MTC). Recent studies reported a high proportion of RAS somatic mutations in RET negative tumours, which may indicate RAS mutation as a possible alternative genetic event in sporadic MTC tumorigenesis. Thus, the aim of the study was to evaluate the frequency of somatic RAS mutations in sporadic medullary thyroid cancer in the Polish population and to relate the obtained data to the presence of somatic RET mutations.Material and methods: Somatic mutations (RET, RAS genes) were evaluated in 78 snap-frozen MTC samples (57 sporadic and 21 hereditary) by direct sequencing. Next, three randomly selected RET-negative MTC samples were analysed by the next generation sequencing.Results: RAS mutation was detected in 26.5% of 49 sporadic MTC tumours. None of all the analysed samples showed N-RAS mutation. When only RET-negative samples were considered, the prevalence of RAS mutation was 68.7%, compared to 6% observed in RET-positive samples. Most of these mutations were located in H-RAS codon 61 (72%). None of 21 hereditary MTC samples showed any RAS mutations.Conclusions: RAS mutations constitute a frequent molecular event in RET-negative sporadic medullary thyroid carcinoma in Polish patients. However, their role in MTC tumorigenesis remains unclear. (Endokrynol Pol 2015; 66 (2): 121–125)Wstęp: Somatyczne mutacje proto-onkogenu RET wykrywane są w trzech czwartych wszystkich sporadycznych raków rdzeniastych tarczycy (MTC). Ostatnie badania wykazały, że mutacja genu RAS jest również częstym wydarzeniem w sporadycznych guzach MTC, co może oznaczać, że mutacje genów z rodziny RAS są alternatywnym wydarzeniem molekularnym w kancerogezie sporadycznej postaci tego raka. Z tego względu celem niniejszej pracy było oszacowanie częstości występowania mutacji genów RAS w sporadycznym raku rdzeniastym tarczycy w populacji polskiej i odniesieniu częstości ich występowania do obecności mutacji somatycznych proto-onkogenu RET.Materiał i metody: Materiał do badań stanowiło 78 fragmentów guza raka rdzeniastego tarczycy (57 próbek postaci sporadycznej i 21 dziedzicznej MTC). Analizowano mutacje genu RET, H-RAS, K-RAS i N-RAS metodą bezpośredniego sekwencjonowania a także 3 próbki raka sporadycznego, wybrane losowo, zostały zeskwencjonowane metodą głębokiego sekwencjonowania (Illumina).Wyniki: Mutację genów RAS wykryto w 26,5% z 49 przeanalizowanych guzów sporadycznej postaci MTC. Natomiast, gdy tylko brano pod uwagę próbki RET-negatywne, częstość występowania mutacji genów RAS wynosiła 68,7% w porównaniu z 6% obserwowanych w guzach RET-pozytywnych. Nie wykryto, w żadnej z próbek, mutacji genu N-RAS. Najczęściej wykrywaną mutacją była zmiana w kodonie 61 genu H-RAS (72%). Nie wykryto mutacji genów RAS w żadnej z próbek dziedzicznego guza raka tarczycy.Wnioski: Mutacje somatyczne genów RAS są częstym wydarzeniem obserwowanym w RET-negatywnych sporadycznych rakach rdzeniastych tarczycy w populacji polskiej. Jednakże rola tych mutacji w rozwoju rdzeniastego raka tarczycy nie jest do końca poznana. (Endokrynol Pol 2015; 66 (2): 121–125

Epidermal differentiation complex (locus 1q21) gene expression in head and neck cancer and normal mucosa

Epidermal differentiation complex (EDC) comprises a number of genes associated with human skin diseases including psoriasis, atopic dermatitis and hyperkeratosis. These genes have also been linked to numerous cancers, among them skin, gastric, colorectal, lung, ovarian and renal carcinomas. The involvement of EDC components encoding S100 proteins, small proline-rich proteins (SPRRs) and other genes in the tumorigenesis of head and neck squamous cell cancer (HNSCC) has been previously suggested. The aim of the study was to systematically analyze the expression of EDC components on the transcript level in HNSCC. Tissue specimens from 93 patients with HNC of oral cavity and 87 samples from adjacent or distant grossly normal oral mucosawere analyzed. 48 samples (24 tumor and 24 corresponding surrounding tissue) were hybridized to Affymetrix GeneChip Human 1.0 ST Arrays. For validation by quantitative real-time PCR (QPCR) the total RNA from all 180 samples collected in the study was analyzed with Real-Time PCR system and fluorescent amplicon specific-probes. Additional set of samples from 14 patients with laryngeal carcinoma previously obtained by HG-U133 Plus 2.0 microarray was also included in the analyses. The expression of analyzed EDC genes was heterogeneous. Two transcripts (S100A1 and S100A4) were significantly down-regulated in oral cancer when compared to normal mucosa (0.69 and 0.36-fold change, respectively), showing an opposite pattern of expression to the remaining S100 genes. Significant up-regulation in tumors was found for S100A11, S100A7, LCE3D, S100A3 and S100A2 genes. The increased expression of S100A7 was subsequently validated by QPCR, confirming significant differences. The remaining EDC genes, including all encoding SPRR molecules, did not show any differences between oral cancer and normal mucosa. The observed differences were also assessed in the independent set of laryngeal cancer samples, confirming the role of S100A3 and LCE3D transcripts in HNC. In HNC of oral cavity only one family of EDC genes (S100 proteins) showed significant cancer-related differences. A number of other transcripts which showed altered expression in HNC require further validation.