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1.
Sensors (Basel) ; 24(9)2024 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-38732863

RESUMEN

Cloud computing has become a major component of the modern IT ecosystem. A key contributor to this has been the development of Infrastructure as a Service (IaaS) architecture, in which users' virtual machines (VMs) are run on the service provider's physical infrastructure, making it possible to become independent of the need to purchase one's own physical machines (PMs). One of the main aspects to consider when designing such systems is achieving the optimal utilization of individual resources, such as processor, RAM, disk, and available bandwidth. In response to these challenges, the authors developed an analytical model (the ARU method) to determine the average utilization levels of the aforementioned resources. The effectiveness of the proposed analytical model was evaluated by comparing the results obtained by utilizing the model with those obtained by conducting a digital simulation of the operation of a cloud system according to the IaaS paradigm. The results show the effectiveness of the model regardless of the structure of the emerging requests, the variability of the capacity of individual resources, and the number of physical machines in the system. This translates into the applicability of the model in the design process of cloud systems.

2.
Sensors (Basel) ; 24(2)2024 Jan 22.
Artículo en Inglés | MEDLINE | ID: mdl-38276389

RESUMEN

Handoff mechanisms are very important in fifth-generation (5G) mobile networks because of the cellular architecture employed to maximize spectrum utilization. Together with call admission control (CAC) mechanisms, they enable better optimization of bandwidth use. The primary objective of the research presented in this article is to analyze traffic levels, aiming to optimize traffic management and handling. This article considers the two most popular CAC mechanisms: the resource reservation mechanism and the threshold mechanism. It presents an analytical approach to occupancy distribution and blocking probability calculation in 5G mobile networks, incorporating connection handoff and CAC mechanisms for managing multiple traffic streams generated by multi-service sources. Due to the fact that the developed analytical model is an approximate model, its accuracy was also examined. For this purpose, the results of analytical calculations of the blocking probability in a group of 5G cells are compared with the simulation data. This paper is an extended version of our paper published in 17th ConTEL 2023.

3.
Life (Basel) ; 11(12)2021 Dec 07.
Artículo en Inglés | MEDLINE | ID: mdl-34947885

RESUMEN

Pseudogenes were once considered as "junk DNA", due to loss of their functions as a result of the accumulation of mutations, such as frameshift and presence of premature stop-codons and relocation of genes to inactive heterochromatin regions of the genome. Pseudogenes are divided into two large groups, processed and unprocessed, according to their primary structure and origin. Only 10% of all pseudogenes are transcribed into RNAs and participate in the regulation of parental gene expression at both transcriptional and translational levels through senseRNA (sRNA) and antisense RNA (asRNA). In this review, about 150 pseudogenes in the different types of cancers were analyzed. Part of these pseudogenes seem to be useful in molecular diagnostics and can be detected in various types of biological material including tissue as well as biological fluids (liquid biopsy) using different detection methods. The number of pseudogenes, as well as their function in the human genome, is still unknown. However, thanks to the development of various technologies and bioinformatic tools, it was revealed so far that pseudogenes are involved in the development and progression of certain diseases, especially in cancer.

4.
Cancers (Basel) ; 13(12)2021 Jun 12.
Artículo en Inglés | MEDLINE | ID: mdl-34204634

RESUMEN

Head and neck squamous cell carcinoma is one of the most common and fatal cancers worldwide. Even a multimodal approach consisting of standard chemo- and radiotherapy along with surgical resection is only effective in approximately 50% of the cases. The rest of the patients develop a relapse of the disease and acquire resistance to treatment. Especially this group of individuals needs novel, personalized, targeted therapy. The first step to discovering such solutions is to investigate the tumor microenvironment, thus understanding the role and mechanism of the function of coding and non-coding sequences of the human genome. In recent years, RNA molecules gained great interest when the complex character of their impact on our biology allowed them to come out of the shadows of the "junk DNA" label. Furthermore, long non-coding RNAs (lncRNA), specifically the intergenic subgroup (lincRNA), are one of the most aberrantly expressed in several malignancies, which makes them particularly promising future diagnostic biomarkers and therapeutic targets. This review contains characteristics of known and validated lincRNAs in HNSCC, such as XIST, MALAT, HOTAIR, HOTTIP, lincRNA-p21, LINC02487, LINC02195, LINC00668, LINC00519, LINC00511, LINC00460, LINC00312, and LINC00052, with a description of their prognostic abilities. Even though much work remains to be done, lincRNAs are important factors in cancer biology that will become valuable biomarkers of tumor stage, outcome prognosis, and contribution to personalized medicine.

5.
Contemp Oncol (Pozn) ; 24(2): 96-105, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32774134

RESUMEN

INTRODUCTION: Nuclear paraspeckle assembly transcript 1 (NEAT1) is considered an oncogene in various cancers, but the role in head and neck squamous cell carcinomas (HNSCC) is not clear. MATERIAL AND METHODS: Expression of NEAT1 in HNSCC patients' samples and cell lines was analysed using qRT-PCR. The TCGA expression data of NEAT1 were analysed depending on the clinicopathological parameters and tumour localisation. Correlation and gene set enrichment analysis (GSEA) were conducted, and the results were analysed using the REACTOME and GeneMANIA tools. All statistical analyses were carried out using GraphPad Prism 5 and Statistica 13. RESULTS: The NEAT1 was up-regulated in some patients' samples and HNSCC cell lines. Moreover, TCGA data analysis indicated that the expression of NEAT1 was up-regulated in tumour tissue in most of the analysed TCGA cancers, including HNSCC. There were no significant differences in levels of NEAT1 between various tumour localisations. Overall survival of individuals with high expression of NEAT1 was slightly longer than in the low-expression group (p = 0.0553). Analysis of genes that positively and negatively correlated with NEAT1 indicated that they are involved in mRNA metabolism and cellular transport. Moreover, the GSEA revealed that in patients with low NEAT1, the most up-regulated genes were in clusters associated with the cAMP-dependent pathway, the MYC pathway, unfolded protein response, the MTORC1 signalling pathway, oxidative phosphorylation, and DNA repair. CONCLUSIONS: Patients with low expression of NEAT1 display worse overall survival, presumably due to up-regulation of certain oncogenic signalling pathways that are important for cancerogenesis.

6.
Cells ; 9(5)2020 05 21.
Artículo en Inglés | MEDLINE | ID: mdl-32455790

RESUMEN

YRNAs are a class of non-coding RNAs that are components of the Ro60 ribonucleoprotein particle and are essential for initiation of DNA replication. Ro60 ribonucleoprotein particle is a target of autoimmune antibodies in patients suffering from systemic lupus erythematosus and Sjögren's syndrome. Deregulation of YRNAs has been confirmed in many cancer types, but not in head and neck squamous cell carcinoma (HNSCC). The main aim of this study was to determine the biological role of YRNAs in HNSCC, the expression of YRNAs, and their usefulness as potential HNSCC biomarkers. Using quantitative reverse transcriptase (qRT)-PCR, the expression of YRNAs was measured in HNSCC cell lines, 20 matched cancer tissues, and 70 FFPETs (Formaline-Fixed Paraffin-Embedded Tissue) from HNSCC patients. Using TCGA (The Cancer Genome Atlas) data, an analysis of the expression levels of selected genes, and clinical-pathological parameters was performed. The expression of low and high YRNA1 expressed groups were analysed using gene set enrichment analysis (GSEA). YRNA1 and YRNA5 are significantly downregulated in HNSCC cell lines. YRNA1 was found to be significantly downregulated in patients' tumour sample. YRNAs were significantly upregulated in T4 stage. YRNA1 showed the highest sensitivity, allowing to distinguish healthy from cancer tissue. An analysis of TCGA data revealed that expression of YRNA1 was significantly altered in the human papilloma virus (HPV) infection status. Patients with medium or high expression of YRNA1 showed better survival outcomes. It was noted that genes correlated with YRNA1 were associated with various processes occurring during cancerogenesis. The GSEA analysis showed high expression enrichment in eight vital processes for cancer development. YRNA1 influence patients' survival and could be used as an HNSCC biomarker. YRNA1 seems to be a good potential biomarker for HNSCC, however, more studies must be performed and these observations should be verified using an in vitro model.


Asunto(s)
Neoplasias de Cabeza y Cuello/genética , ARN no Traducido/metabolismo , Carcinoma de Células Escamosas de Cabeza y Cuello/genética , Anciano , Línea Celular Tumoral , Supervivencia sin Enfermedad , Femenino , Regulación Neoplásica de la Expresión Génica , Humanos , Masculino , Papillomaviridae/fisiología , ARN no Traducido/genética , Curva ROC , Carcinoma de Células Escamosas de Cabeza y Cuello/virología , Resultado del Tratamiento
7.
Nutr Neurosci ; 5(4): 221-8, 2002 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-12168684

RESUMEN

The processes of food and fluid acquisition are necessary for the preservation of the animal's integrity. This review describes behavioral investigations concerning the role of one experiential factor in early infancy, that of, prior diet and its effect on the development of solid food preferences in cats. The results are presented in a broader investigative context, which includes behavioral data obtained both on precocial and altricial species. The emphasis of this review is on the two tendencies established by prior dietary experiences with nutritionally complete foods on later food preferences: the primacy effect and the novelty effect. The primacy effect is a preference of adult animals for their rearing diet, while the novelty effect is a preference for a novel diet. The latest attempt to explain these apparently contradictory effects is described. That is, if the taste environment is rich in many tastes of food in early life, the potential palatability of some foods may be masked or overshadowed; in contrast, if that environment is restricted to one specific food, the potential palatability of some foods may be revealed.


Asunto(s)
Conducta Animal , Gatos/fisiología , Preferencias Alimentarias , Envejecimiento , Animales , Condicionamiento Psicológico , Corteza Prefrontal/crecimiento & desarrollo , Corteza Prefrontal/fisiología , Gusto
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