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BACKGROUND: The conservation of aquatic and semiaquatic turtles requires knowledge of the area and vegetation structure of habitat used for nesting, and nesting migration route. We aimed to survey the effects of habitat features to the nest site selection, nesting success, and test the possibility of nest site fidelity. Our study was carried out at 10 different nesting areas, with special emphasis on data from returning females in a pond system in Hungary between 2014 and 2017. RESULTS: Most nesting attempts were found in closed sand steppes, uncharacteristic dry and semi-dry grasslands habitat patches. The principal component analysis (PCA) showed that increased sandy soil cover, sunlight and slope were important variables in nest site choice. The increasing PCA first axis score significantly increased the chance of an emergence. The degradation of open steppe vegetation, occurrence of weeds, invasive and disturbance tolerant species have a negative effect on the selection of nest sites. We observed that 96.55% of nests were located within 20 m south of a pine forest at preferred nest site at pond 5, which provided the right incubation temperature through partial shading. The returning females nested significantly closer to the northern pine forest than the single clutch females. Most probably the returning females already has the necessary experience to select the right nesting site. The individually marked females did not choose new nesting areas during the monitored years which suggests nesting area fidelity, but we did not find nest site fidelity. CONCLUSION: The maintenance of mosaic habitat structure, slowing down the succession process at the nesting area should be basic priorities in European pond turtle conservation programs. We suggested a spatial and temporal scheduling of land management and agricultural work to the local farmers. If the actual nest site is in an agricultural area, all work should be avoided throughout the year. Agricultural machinery should avoid the migration routes of adult turtles and emerged hatchlings during the concerned period. Under strong predation pressure, predator control should be carried out, and use nest protection.
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Corrosion processes are often discussed as stochastic events. Here, it is shown that some of these seemingly random processes are not driven by nanoscopic fluctuations but rather by the spatial distribution of micrometer-scale heterogeneities that trigger fast reactions associated with corrosion. Using a novel excitable reaction-diffusion model, corrosion waves traveling over the metal surface and the associated material loss are described. This resulting nonuniform corrosion penetration, seen as a height loss in modeling, exposes buried intermetallic particles, which depending on the local electrochemical state of the surface trigger or block new waves. Informed by quantitative experimental data for the Mg-Al-Zn alloy AZ31B, wave speeds, wave widths, and average material loss are accurately captured. Morphogenic mitigation based on wave-breaking microparticles is also simulated. While AZ31B corrosion is identified as a process driven by rare-wave events, this study predicts several other corrosion regimes that proceed via spots or patchy patterns, opening the door for new protection, design, and prediction strategies.
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Synchronization of coupled oscillators is a universal phenomenon encountered across different scales and contexts, e.g., chemical wave patterns, superconductors, and the unison applause we witness in concert halls. The existence of common underlying coupling rules defines universality classes, revealing a fundamental sameness between seemingly distinct systems. Identifying rules of synchronization in any particular setting is hence of paramount relevance. Here, we address the coupling rules within an embryonic oscillator ensemble linked to vertebrate embryo body axis segmentation. In vertebrates, the periodic segmentation of the body axis involves synchronized signaling oscillations in cells within the presomitic mesoderm (PSM), from which somites, the prevertebrae, form. At the molecular level, it is known that intact Notch-signaling and cell-to-cell contact are required for synchronization between PSM cells. However, an understanding of the coupling rules is still lacking. To identify these, we develop an experimental assay that enables direct quantification of synchronization dynamics within mixtures of oscillating cell ensembles, for which the initial input frequency and phase distribution are known. Our results reveal a "winner-takes-it-all" synchronization outcome, i.e., the emerging collective rhythm matches one of the input rhythms. Using a combination of theory and experimental validation, we develop a coupling model, the "Rectified Kuramoto" (ReKu) model, characterized by a phase-dependent, nonreciprocal interaction in the coupling of oscillatory cells. Such nonreciprocal synchronization rules reveal fundamental similarities between embryonic oscillators and a class of collective behaviors seen in neurons and fireflies, where higher-level computations are performed and linked to nonreciprocal synchronization.
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Padronização Corporal , Animais , Padronização Corporal/fisiologia , Relógios Biológicos/fisiologia , Embrião não Mamífero/fisiologia , Transdução de Sinais/fisiologia , Somitos/embriologia , Mesoderma/embriologia , Modelos BiológicosRESUMO
We investigate the entrainment of electrochemical oscillators with different phase response curves (PRCs) using a global signal: the goal is to achieve the desired phase configuration using a minimum-power waveform. Establishing the desired phase relationships in a highly nonlinear networked system exhibiting significant heterogeneities, such as different conditions or parameters for the oscillators, presents a considerable challenge because different units respond differently to the common global entraining signal. In this work, we apply an optimal phase-selective entrainment technique in both a kinetic model and experiments involving electrochemical oscillators in achieving phase synchronized states. We estimate the PRCs of the oscillators at different circuit potentials and external resistance, and entrain pairs and small sets of four oscillators in various phase configurations. We show that for small PRC variations, phase assignment can be achieved using an averaged PRC in the control design. However, when the PRCs are sufficiently different, individual PRCs are needed to entrain the system with the expected phase relationships. The results show that oscillator assemblies with heterogeneous PRCs can be effectively entrained to desired phase configurations in practical settings. These findings open new avenues to applications in biological and engineered oscillator systems where synchronization patterns are essential for system performance.
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The aim of our study was to compare the characteristics and time to initial physician contact in patients with head and neck squamous cell carcinoma (HNSCC) before and during the COVID-19 pandemic at a large Hungarian cancer center. This was a retrospective study of patients 18 years or older presenting at the regional cancer center of Pécs Clinical Center with HNSCC between 1 January 2017, and 15 March 2020 (the pre-COVID-19 period) and between 16 March 2020, and 13 May 2021 (the COVID-19 period). Demographic and clinical data were collected, and the time between initial symptom onset and initial physician contact (TTP) was determined. Descriptive and exploratory statistical analyses were performed. On average, the number of patients diagnosed with HNSCC per month during the pandemic decreased by 12.4% compared with the pre-COVID-19 period. There was a significant increase in stage I and stage II cancers (from 15.9% to 20.3% and from 12.2% to 13.8%, respectively; p < 0.001); a decrease in stage III and IVa,c cancers; and a significant increase in stage IVb cancers (from 6% to 19.9%; p < 0.001) during the pandemic. The median TTP increased during the pandemic from 43 to 61 days (p = 0.032). To our knowledge, this is the first study investigating the effect of COVID-19 on patients with HNSCC in the Central-Eastern European region. We found a bidirectional shift in cancer stages and increased TTP during the pandemic. Our findings highlight the necessity for more nuanced analyses of the effects of COVID-19.
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One of a major function of programmed cell death (apoptosis) is the removal of cells which suffered oncogenic mutations, thereby preventing cancerous transformation. By making use of a Double-Headed-EP (DEP) transposon, a P element derivative made in our laboratory, we made an insertional mutagenesis screen in Drosophila melanogaster to identify genes which, when overexpressed, suppress the p53-activated apoptosis. The DEP element has Gal4-activatable, outward-directed UAS-promoters at both ends which can be deleted separately in vivo. In the DEP insertion mutants, we used the GMR-Gal4 driver to induce transcription from both UAS-promoters and tested the suppression effect on the apoptotic rough eye phenotype generated by an activated UAS-p53 transgene. By DEP insertions, seven genes were identified which suppressed the p53-induced apoptosis. In four mutants, the suppression effect resulted from single genes activated by one UAS-promoter (Pka-R2, Rga, crol, Spt5). In the other three (Orct2, Polr2M, stg), deleting either UAS-promoter eliminated the suppression effect. In qPCR experiments we found that the genes in the vicinity of the DEP insertion also showed an elevated expression level. This suggested an additive effect of the nearby genes on suppressing apoptosis. In the eucaryotic genomes there are co-expressed gene clusters. Three of the DEP insertion mutants are included and two are in close vicinity of separate co-expressed gene clusters. This raises the possibility that the activity of some of the genes in these clusters may help the suppression of the apoptotic cell death.
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Introduction: Patients with advanced cancer tend to utilize the services of the health care system, particularly emergency departments (EDs), more often, however EDs aren't necessarily the most ideal environments for providing care to these patients. The objective of our study was to analyze the clinical and demographic characteristics of advanced patients with cancer receiving basic palliative care (BPC) or hospice care (HC), and to identify predictive factors of BPC and HC prior to their visit to the ED, in a large tertiary care center in Hungary. Methods: A retrospective, detailed analysis of patients receiving only BPC or HC, out of 1512 patients with cancer visiting the ED in 2018, was carried out. Sociodemographic and clinical data were collected via automated and manual chart review. Patients were followed up to determine length of survival. Descriptive and exploratory statistical analyses were performed. Results: Hospital admission, multiple (≥4x) ED visits, and respiratory cancer were independent risk factors for receiving only BPC (OR: 3.10, CI: 1.90-5.04; OR: 2.97, CI: 1.50-5.84; OR: 1.82, CI: 1.03-3.22, respectively), or HC (OR: 2.15, CI: 1.26-3.67; OR: 4.94, CI: 2.51-9.71; OR: 2.07, CI: 1.10-3.91). Visiting the ED only once was found to be a negative predictive factor for BPC (OR: 0.28, CI: 0.18-0.45) and HC (OR: 0.18, 0.10-0.31) among patients with cancer visiting the ED. Conclusions: Our study is the first from this European region to provide information regarding the characteristics of patients with cancer receiving BPC and HC who visited the ED, as well as to identify possible predictive factors of receiving BPC and HC. Our study may have relevant implications for health care planning strategies in practice.
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Background: Women are typically diagnosed with estrogen receptor-positive breast cancer around the postmenopausal period when declining estrogen levels initiate changes in lipid profiles. Aromatase inhibitors (AI) are used to prevent the progression of cancer; however, a further reduction in estrogen levels may have detrimental effects on lipid levels, which was our working hypothesis. Methods: Our meta-analysis was conducted on the lipid profiles of postmenopausal breast cancer patients at baseline and at different treatment time points. Results: We identified 15 studies, including 1708 patients. Studies using anastrozole (ANA), exemestane (EXE), letrozole (LET), and tamoxifen (TMX) were involved. Subgroup analyses revealed that 3- and 12-month administrations of LET and EXE lead to negative changes in lipid profiles that tend to alter the lipid profile undesirably, unlike ANA and TMX. Conclusions: Our results suggest that, despite statistically significant results, EXE and LET may not be sufficient to cause severe dyslipidemia in patients without cardiovascular comorbidities according to the AHA/ACC Guideline on the Management of Blood Cholesterol. However, the results may raise the question of monitoring the effects of AIs in patients, especially those with pre-existing cardiovascular risk factors such as dyslipidemia.
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Interventions to mitigate the spread of infectious diseases, while succeeding in their goal, have economic and social costs associated with them. These limit the duration and intensity of the interventions. We study a class of interventions which reduce the reproduction number and find the optimal strength of the intervention which minimizes the final epidemic size for an immunity inducing infection. The intervention works by eliminating the overshoot part of an epidemic, and avoids a second wave of infections. We extend the framework by considering a heterogeneous population and find that the optimal intervention can pose an ethical dilemma for decision and policymakers. This ethical dilemma is shown to be analogous to the trolley problem. We apply this optimization strategy to real-world contact data and case fatality rates from three pandemics to underline the importance of this ethical dilemma in real-world scenarios.
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Epidemias , PandemiasRESUMO
Epidemic propagation on networks represents an important departure from traditional mass-action models. However, the high-dimensionality of the exact models poses a challenge to both mathematical analysis and parameter inference. By using mean-field models, such as the pairwise model (PWM), the high-dimensionality becomes tractable. While such models have been used extensively for model analysis, there is limited work in the context of statistical inference. In this paper, we explore the extent to which the PWM with the susceptible-infected-recovered (SIR) epidemic can be used to infer disease- and network-related parameters. Data from an epidemics can be loosely categorised as being population level, e.g., daily new cases, or individual level, e.g., recovery times. To understand if and how network inference is influenced by the type of data, we employed the widely-used MLE approach for population-level data and dynamical survival analysis (DSA) for individual-level data. For scenarios in which there is no model mismatch, such as when data are generated via simulations, both methods perform well despite strong dependence between parameters. In contrast, for real-world data, such as foot-and-mouth, H1N1 and COVID19, whereas the DSA method appears fairly robust to potential model mismatch and produces parameter estimates that are epidemiologically plausible, our results with the MLE method revealed several issues pertaining to parameter unidentifiability and a lack of robustness to exact knowledge about key quantities such as population size and/or proportion of under reporting. Taken together, however, our findings suggest that network-based mean-field models can be used to formulate approximate likelihoods which, coupled with an efficient inference scheme, make it possible to not only learn about the parameters of the disease dynamics but also that of the underlying network.
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Epidemias , Vírus da Influenza A Subtipo H1N1 , Modelos Biológicos , Conceitos Matemáticos , ProbabilidadeRESUMO
Fowl adenovirus 1 (FAdV-1) is the main cause of gizzard erosion in chickens. Whole genome sequencing and sequence analyses of 32 FAdV-1 strains from a global collection provided evidence that multiple recombination events have occurred along the entire genome. In gene-wise phylogenies, only the adenoviral pol gene formed a tree topology that corresponded to whole genome-based phylogeny. Virus genetic features that were clearly connected to gizzard erosion were not identified in our analyses. However, some genome variants tended to be more frequently identified from birds with gizzard erosion and strains isolated from healthy birds or birds with non-specific pathologies tended to form common clusters in multiple gene phylogenies. Our data show that the genetic diversity is greater, and the evolutionary mechanisms are more complex within FAdV-1 than previously thought. The implications of these findings for viral pathogenesis and epidemiology await further investigation.
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Lung cancer has emerged as a significant public health challenge and remains the leading cause of cancer-related mortality worldwide. Among various types of lung malignancies, lung adenocarcinoma (LUAD) stands as the most prevalent form. MicroRNAs (miRNAs) play a crucial role in gene regulation, and their involvement in cancer has been extensively explored. While several reviews have been published on miRNAs and lung cancer, there remains a gap in the review regarding miRNAs specifically in LUAD. In this review, we not only highlight the potential diagnostic, prognostic, and therapeutic implications of miRNAs in LUAD, but also present an inclusive overview of the extensive research conducted on miRNAs in this particular context.
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Adenocarcinoma de Pulmão , Neoplasias Pulmonares , MicroRNAs , Humanos , Adenocarcinoma de Pulmão/diagnóstico , Adenocarcinoma de Pulmão/genética , Adenocarcinoma de Pulmão/terapia , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/terapia , MicroRNAs/genética , Saúde PúblicaRESUMO
The spatiotemporal organization of networks of dynamical units can break down resulting in diseases (e.g., in the brain) or large-scale malfunctions (e.g., power grid blackouts). Re-establishment of function then requires identification of the optimal intervention site from which the network behavior is most efficiently re-stabilized. Here, we consider one such scenario with a network of units with oscillatory dynamics, which can be suppressed by sufficiently strong coupling and stabilizing a single unit, i.e., pinning control. We analyze the stability of the network with hyperbolas in the control gain vs coupling strength state space and identify the most influential node (MIN) as the node that requires the weakest coupling to stabilize the network in the limit of very strong control gain. A computationally efficient method, based on the Moore-Penrose pseudoinverse of the network Laplacian matrix, was found to be efficient in identifying the MIN. In addition, we have found that in some networks, the MIN relocates when the control gain is changed, and thus, different nodes are the most influential ones for weakly and strongly coupled networks. A control theoretic measure is proposed to identify networks with unique or relocating MINs. We have identified real-world networks with relocating MINs, such as social and power grid networks. The results were confirmed in experiments with networks of chemical reactions, where oscillations in the networks were effectively suppressed through the pinning of a single reaction site determined by the computational method.
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We prove that it is possible to obtain the exact closure of SIR pairwise epidemic equations on a configuration model network if and only if the degree distribution follows a Poisson, binomial, or negative binomial distribution. The proof relies on establishing the equivalence, for these specific degree distributions, between the closed pairwise model and a dynamical survival analysis (DSA) model that was previously shown to be exact. Specifically, we demonstrate that the DSA model is equivalent to the well-known edge-based Volz model. Using this result, we also provide reductions of the closed pairwise and Volz models to a single equation that involves only susceptibles. This equation has a useful statistical interpretation in terms of times to infection. We provide some numerical examples to illustrate our results.
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Doenças Transmissíveis , Epidemias , Humanos , Modelos Biológicos , Doenças Transmissíveis/epidemiologia , Epidemias/prevenção & controle , Suscetibilidade a Doenças/epidemiologiaRESUMO
The synchronization dynamics for the circadian gene expression in the suprachiasmatic nucleus is investigated using a transcriptional circadian clock gene oscillator model. With global coupling in constant dark (DD) conditions, the model exhibits a one-cluster phase synchronized state, in dim light (dim LL), bistability between one- and two-cluster states and in bright LL, a two-cluster state. The two-cluster phase synchronized state, where some oscillator pairs synchronize in-phase, and some anti-phase, can explain the splitting of the circadian clock, i.e., generation of two bouts of daily activities with certain species, e.g., with hamsters. The one- and two-cluster states can be reached by transferring the animal from DD or bright LL to dim LL, i.e., the circadian synchrony has a memory effect. The stability of the one- and two-cluster states was interpreted analytically by extracting phase models from the ordinary differential equation models. In a modular network with two strongly coupled oscillator populations with weak intragroup coupling, with appropriate initial conditions, one group is synchronized to the one-cluster state and the other group to the two-cluster state, resulting in a weak-chimera state. Computational modeling suggests that the daily rhythms in sleep-wake depend on light intensity acting on bilateral networks of suprachiasmatic nucleus (SCN) oscillators. Addition of a network heterogeneity (coupling between the left and right SCN) allowed the system to exhibit chimera states. The simulations can guide experiments in the circadian rhythm research to explore the effect of light intensity on the complexities of circadian desynchronization.
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Ritmo Circadiano , Núcleo Supraquiasmático , Cricetinae , Animais , Simulação por Computador , Escuridão , Análise por ConglomeradosRESUMO
Consumption of energy drinks is harmful in childhood and adolescence, and its increasing popularity makes it a public health threat in this age group. Our study aimed to assess energy drink (ED) consumption and identify the context and determinants of its consumption at a Hungarian primary school. A mixed-method approach was used for the research, including a survey filled in by 157 10-15-year-old pupils and World Café workshops (WCWs) involving pupils, home-room teachers, and Parental Council representatives (N = 39). The Jamovi 2.2.5. The software was used to perform descriptive statistics and logistic regression, and a causal loop diagram was created based on the results of the WCWs. The survey results revealed that almost one-third of the pupils consumed EDs regularly, and most daily consumers drank high amounts (500ml). Most students considered ED consumption unhealthy, yet every fifth drank them. Buying breakfast on the way to school increased the odds of ED consumption almost threefold. According to the WCWs' findings, the determinants of ED consumption were embedded in two critical contextual sets; one was the need for energy and concentration boost and the Perception of high social acceptance of ED consumption. Our results suggest that interventions to reduce students' ED consumption need to include increased parents' involvement in controlling their children's screen time and encouraging them to provide breakfast at home for their children. There is also an urgent need to restrict the marketing of EDs and strictly regulate access to EDs for under-18s.
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OBJECTIVES: To identify predictive factors of multiple emergency department (ED) visits, hospitalisation and potentially preventable ED visits made by patients with cancer in a Hungarian tertiary care centre. DESIGN: Observational, retrospective study. SETTING: A large, public tertiary hospital, in Somogy County, Hungary, with a level 3 emergency and trauma centre and a dedicated cancer centre. PARTICIPANTS: Patients above 18 years with a cancer diagnosis (International Classification of Diseases, 10th Revision codes of C0000-C9670) who visited the ED in 2018, who had received their diagnosis of cancer within 5 years of their first ED visit in 2018 or received their diagnosis of cancer latest within the study year. Cases diagnosed with cancer at the ED (new cancer diagnosis-related ED visits) were also included, constituting 7.9% of visits. PRIMARY OUTCOME MEASURES: Demographic and clinical characteristics were collected and the predictors of multiple (≥2) ED visits within the study year, admission to inpatient care following the ED visit (hospitalisation), potentially preventable ED visits and death within 36 months were determined. RESULTS: 2383 ED visits made by 1512 patients with cancer were registered. Predictive factors of multiple (≥2) ED visits were residing in a nursing home (OR 3.09, 95% CI 1.88 to 5.07) and prior hospice care (OR 1.87, 95% CI 1.05 to 3.31). Predictive factors for hospitalisation following an ED visit included a new cancer diagnosis-related visit (OR 1.86, 95% CI 1.30 to 2.66) and complaint of dyspnoea (OR 1.61, 95% CI 1.22 to 2.12). CONCLUSIONS: Being a resident of a nursing home and receiving prior hospice care significantly increased the odds of multiple ED visits, while new cancer-related ED visits independently increased the odds of hospitalisation of patients with cancer. This is the first study to report these associations from a Central-Eastern European country. Our study may shed light on the specific challenges of EDs in general and particularly faced by countries in the region.
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Hospitalização , Neoplasias , Humanos , Estudos Retrospectivos , Centros de Atenção Terciária , Hungria/epidemiologia , Neoplasias/epidemiologia , Neoplasias/terapia , Serviço Hospitalar de EmergênciaRESUMO
Recently, the field of epigenetics has been intensively studied in relation to nutrition. In our study, the gene expression patterns of histone deacetylases (HDACs), which regulate the stability of histone proteins, and DNA methyltransferases (DNMTs), which regulate DNA methylation, were determined in mice. The animals were fed a human-equivalent dose of the aqueous extract of fruit seeds and peels, which is rich in flavonoids and polyphenols, for 28 days and then exposed to the carcinogen 7,12-dimethylbenz(a)anthracene (DMBA). The concentrations of trans-resveratrol and trans-piceid were determined in the consumed extract by HPLC and were 1.74 mg/L (SD 0.13 mg/L) and 2.37 mg/L (SD 0.32 mg/L), respectively, which corresponds to the consumption of 0.2-1 L of red wine, the main dietary source of resveratrol, in humans daily. Subsequently, 24 h after DMBA exposure, the expression patterns of the HDAC and DNMT genes in the liver and kidneys were determined by qRT-PCR. The DMBA-induced expression of the tested genes HDAC1, HDAC2, DNMT1, DNMT3A and DNMT3B was reduced in most cases by the extract. It has already been shown that inhibition of the DNMT and HDAC genes may delay cancer development and tumour progression. We hypothesise that the extract studied may exert chemopreventive effects.
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Flavonoides , Polifenóis , Humanos , Animais , Camundongos , Flavonoides/farmacologia , Polifenóis/farmacologia , Frutas , Epigênese Genética , Metilação de DNA , Metilases de Modificação do DNA , ResveratrolRESUMO
Background: Single nucleotide polymorphisms (SNPs) interfere with the function of certain genes and thus may influence the probability of skin cancer. The correlation between SNPs and skin cancer (SC) lacks statistical power, however. Therefore, the purpose of this study was to identify the gene polymorphisms involved in skin cancer susceptibility using network meta-analysis and to determine the relationship between SNPs and SC risk. Methods: PubMed, Embase, and Web of Science were searched for articles including "SNP" and different types of SC as keywords between January 2005 and May 2022. The Newcastle-Ottawa Scale was used to assess bias judgments. The odds ratio (ORs) and their 95% confidence intervals (CIs) were determined to estimate heterogeneity within and between studies. Meta-analysis and network meta-analysis were carried out to identify the SNPs associated with SC. The P-score of each SNP was compared to obtain the rank of probability. Subgroup analyses were performed by cancer type. Results: A total of 275 SNPs from 59 studies were included in the study. Two subgroup SNP networks using the allele model and dominant model were analyzed. The alternative alleles of rs2228570 (FokI) and rs13181 (ERCC2) were the first-ranking SNPs in both subgroups one and two of the allele model, respectively. The homozygous dominant genotype and heterozygous genotype of rs475007 in subgroup one and the homozygous recessive genotype of rs238406 in subgroup two were most likely to be associated with skin cancer based on the dominant model. Conclusions: According to the allele model, SNPs FokI rs2228570 and ERCC2 rs13181 and, according to the dominant model, SNPs MMP1 rs475007 and ERCC2 rs238406 are closely linked to SC risk.