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1.
Dis Model Mech ; 17(6)2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38415925

RESUMO

Cholangiocarcinoma (CCA) is a deadly and heterogeneous type of cancer characterized by a spectrum of epidemiologic associations as well as genetic and epigenetic alterations. We seek to understand how these features inter-relate in the earliest phase of cancer development and through the course of disease progression. For this, we studied murine models of liver injury integrating the most commonly occurring gene mutations of CCA - including Kras, Tp53, Arid1a and Smad4 - as well as murine hepatobiliary cancer models and derived primary cell lines based on these mutations. Among commonly mutated genes in CCA, we found that Smad4 functions uniquely to restrict reactive cholangiocyte expansion to liver injury through restraint of the proliferative response. Inactivation of Smad4 accelerates carcinogenesis, provoking pre-neoplastic biliary lesions and CCA development in an injury setting. Expression analyses of Smad4-perturbed reactive cholangiocytes and CCA lines demonstrated shared enriched pathways, including cell-cycle regulation, MYC signaling and oxidative phosphorylation, suggesting that Smad4 may act via these mechanisms to regulate cholangiocyte proliferation and progression to CCA. Overall, we showed that TGFß/SMAD4 signaling serves as a critical barrier restraining cholangiocyte expansion and malignant transformation in states of biliary injury.


Assuntos
Neoplasias dos Ductos Biliares , Proteínas Proto-Oncogênicas c-myc , Animais , Camundongos , Transdução de Sinais , Carcinogênese/genética , Proliferação de Células , Ductos Biliares Intra-Hepáticos
2.
Microsurgery ; 44(2): e31149, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38363100

RESUMO

There is minimal information regarding free tissue transfers in very young infants, especially those less than a year old. It is often thought that that age remains a limit to free tissue transfers, with younger patients having smaller vessels, making the operation technically challenging. In this case report, we discuss the youngest and smallest recorded case of a free flap reconstruction. A 3-month-old patient with a malignant parapharyngeal undifferentiated round cell sarcoma underwent a resection and reconstruction with a radial forearm free flap (RFFF). The defect was 35 by 20 by 15 mm, and required a pharyngeal "patch," as opposed to a "tube," reconstruction. The defect was templated, and the RFFF then raised in a standard subfascial fashion, and inset with resorbable sutures. The patient was observed in the ICU postoperatively. The patient was subsequently diagnosed with Stage IV primary undifferentiated sarcoma with regional metastasis and received adjuvant chemotherapy. Fifteen-month follow up revealed no signs of recurrence, full oral intake, a well-reconstructed pharynx on nasoendoscopic examination, and minimal donor site morbidity. This report illustrates several unique adaptations of free flap transfer in infants and adds to the emerging body of evidence that age is not a contraindication for head and neck reconstruction.


Assuntos
Retalhos de Tecido Biológico , Procedimentos de Cirurgia Plástica , Sarcoma , Neoplasias de Tecidos Moles , Humanos , Lactente , Faringe , Pescoço , Sarcoma/cirurgia
3.
J Laryngol Otol ; : 1-6, 2024 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-38250823

RESUMO

OBJECTIVE: This study investigates the impact of primary care utilisation of a symptom-based head and neck cancer risk calculator (Head and Neck Cancer Risk Calculator version 2) in the post-coronavirus disease 2019 period on the number of primary care referrals and cancer diagnoses. METHODS: The number of referrals from April 2019 to August 2019 and from April 2020 to July 2020 (pre-calculator) was compared with the number from the period January 2021 to August 2022 (post-calculator) using the chi-square test. The patients' characteristics, referral urgency, triage outcome, Head and Neck Cancer Risk Calculator version 2 score and cancer diagnosis were recorded. RESULTS: In total, 1110 referrals from the pre-calculator period were compared with 1559 from the post-calculator period. Patient characteristics were comparable for both cohorts. More patients were referred on the cancer pathway in the post-calculator cohort (pre-calculator patients 51.1 per cent vs post-calculator 64.0 per cent). The cancer diagnosis rate increased from 2.7 per cent in the pre-calculator cohort to 3.3 per cent in the post-calculator cohort. A lower rate of cancer diagnosis in the non-cancer pathway occurred in the cohort managed using the Head and Neck Cancer Risk Calculator version 2 (10 per cent vs 23 per cent, p = 0.10). CONCLUSION: Head and Neck Cancer Risk Calculator version 2 demonstrated high sensitivity in cancer diagnosis. Further studies are required to improve the predictive strength of the calculator.

4.
Microbiol Resour Announc ; 13(2): e0106623, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38132830

RESUMO

Phage Culver, with a siphovirus morphology, was isolated using Gordonia terrae CAG3. Culver is assigned to phage cluster CQ1 based on gene content similarity to actinobacteriophages. Notably, Culver is predicted to encode eight tRNAs, lysin A by two adjacent genes, and, unlike other CQ1 phages, two putative integrase genes.

5.
Parasit Vectors ; 16(1): 317, 2023 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-37670353

RESUMO

BACKGROUND: Borrelia are important disease-causing tick- and louse-borne spirochaetes than can infect a wide variety of vertebrates, including humans and reptiles. Reptile-associated (REP) Borrelia, once considered a peculiarity, are now recognised as a distinct and important evolutionary lineage, and are increasingly being discovered worldwide in association with novel hosts. Numerous novel Borrelia spp. associated with monitor lizards (Varanus spp.) have been recently identified throughout the Indo-Pacific region; however, there is a lack of genomic data on these Borrelia. METHODS: We used metagenomic techniques to sequence almost complete genomes of novel Borrelia spp. from Varanus varius and Varanus giganteus from Australia, and used long- and short-read technologies to sequence the complete genomes of two strains of a novel Borrelia sp. previously isolated from ticks infesting Varanus salvator from Indonesia. We investigated intra- and interspecies genomic diversity, including plasmid diversity and relatedness, among Varanus-associated Borrelia and other available REP Borrelia and, based on 712 whole genome orthologues, produced the most complete phylogenetic analysis, to the best of our knowledge, of REP Borrelia to date. RESULTS: The genomic architecture of Varanus-associated Borrelia spp. is similar to that of Borrelia spp. that cause relapsing fever (RF), and includes a highly conserved megaplasmid and numerous smaller linear and circular plasmids that lack structural consistency between species. Analysis of PF32 and PF57/62 plasmid partitioning genes indicated that REP Borrelia plasmids fall into at least six distinct plasmid families, some of which are related to previously defined Borrelia plasmid families, whereas the others appear to be unique. REP Borrelia contain immunogenic variable major proteins that are homologous to those found in Borrelia spp. that cause RF, although they are limited in copy number and variability and have low sequence identities to RF variable major proteins. Phylogenetic analyses based on single marker genes and 712 single copy orthologs also definitively demonstrated the monophyly of REP Borrelia as a unique lineage. CONCLUSIONS: In this work we present four new genomes from three novel Borrelia, and thus double the number of REP Borrelia genomes publicly available. The genomic characterisation of these Borrelia clearly demonstrates their distinctiveness as species, and we propose the names Borrelia salvatorii, 'Candidatus Borrelia undatumii', and 'Candidatus Borrelia rubricentralis' for them.


Assuntos
Borrelia , Lagartos , Febre Recorrente , Animais , Humanos , Indonésia , Filogenia , Genômica , Austrália
6.
J Hand Surg Asian Pac Vol ; 28(4): 486-489, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37758494

RESUMO

While there are many proposed surgical treatment options for the correction of swan-neck deformities, none are perfect. We describe a partial flexor digitorum superficialis tenodesis that combines both a static volar plate with a dynamic oblique retinacular ligament vector reconstruction. This is performed through a single, short mid-lateral incision and requires no tendon grafts. The protected early active exercises are encouraged postoperatively, and our long-term results have been promising. The technique was designed for children with cerebral palsy, but the indications have since expanded. Level of Evidence: Level V (Therapeutic).

7.
Nucleic Acids Res ; 51(19): 10147-10161, 2023 10 27.
Artigo em Inglês | MEDLINE | ID: mdl-37738140

RESUMO

CRISPR-Cas9 tools have transformed genetic manipulation capabilities in the laboratory. Empirical rules-of-thumb have been developed for only a narrow range of model organisms, and mechanistic underpinnings for sgRNA efficiency remain poorly understood. This work establishes a novel feature set and new public resource, produced with quantum chemical tensors, for interpreting and predicting sgRNA efficiency. Feature engineering for sgRNA efficiency is performed using an explainable-artificial intelligence model: iterative Random Forest (iRF). By encoding quantitative attributes of position-specific sequences for Escherichia coli sgRNAs, we identify important traits for sgRNA design in bacterial species. Additionally, we show that expanding positional encoding to quantum descriptors of base-pair, dimer, trimer, and tetramer sequences captures intricate interactions in local and neighboring nucleotides of the target DNA. These features highlight variation in CRISPR-Cas9 sgRNA dynamics between E. coli and H. sapiens genomes. These novel encodings of sgRNAs enhance our understanding of the elaborate quantum biological processes involved in CRISPR-Cas9 machinery.


Assuntos
Sistemas CRISPR-Cas , RNA Guia de Sistemas CRISPR-Cas , Inteligência Artificial , DNA , Escherichia coli/genética , Edição de Genes , Humanos
8.
Microbiol Resour Announc ; 12(5): e0014523, 2023 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-37052391

RESUMO

Desulfomicrobium sp. strain ZS1 is an obligate anaerobic, sulfate-reducing member of the Desulfobacterota from Zodletone Spring, an anoxic sulfide-rich spring in southwestern Oklahoma. Its complete genome was sequenced using a combination of Illumina and Oxford Nanopore platforms and encodes 3,364 proteins and 81 RNAs on a single chromosome.

9.
Cogn Affect Behav Neurosci ; 23(3): 691-704, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37058212

RESUMO

Signals related to uncertainty are frequently observed in regions of the cognitive control network, including anterior cingulate/medial prefrontal cortex (ACC/mPFC), dorsolateral prefrontal cortex (dlPFC), and anterior insular cortex. Uncertainty generally refers to conditions in which decision variables may assume multiple possible values and can arise at multiple points in the perception-action cycle, including sensory input, inferred states of the environment, and the consequences of actions. These sources of uncertainty are frequently correlated: noisy input can lead to unreliable estimates of the state of the environment, with consequential influences on action selection. Given this correlation amongst various sources of uncertainty, dissociating the neural structures underlying their estimation presents an ongoing issue: a region associated with uncertainty related to outcomes may estimate outcome uncertainty itself, or it may reflect a cascade effect of state uncertainty on outcome estimates. In this study, we derive signals of state and outcome uncertainty from mathematical models of risk and observe regions in the cognitive control network whose activity is best explained by signals related to state uncertainty (anterior insula), outcome uncertainty (dlPFC), as well as regions that appear to integrate the two (ACC/mPFC).


Assuntos
Imageamento por Ressonância Magnética , Córtex Pré-Frontal , Humanos , Incerteza , Giro do Cíngulo , Cognição
10.
Sci Rep ; 13(1): 1215, 2023 01 21.
Artigo em Inglês | MEDLINE | ID: mdl-36681692

RESUMO

The tubulinopathies are an umbrella of rare diseases that result from mutations in tubulin genes and are frequently characterised by severe brain malformations. The characteristics of a given disease reflect the expression pattern of the transcript, the function of a given tubulin gene, and the role microtubules play in a particular cell type. Mouse models have proved to be valuable tools that have provided insight into the molecular and cellular mechanisms that underlie the disease state. In this manuscript we compare two Tuba1a mouse models, both of which express wild-type TUBA1A protein but employ different codon usage. We show that modification of the Tuba1a mRNA sequence results in homozygous lethality and a severe neurodevelopmental phenotype. This is associated with a decrease in the number of post-mitotic neurons, PAX6 positive progenitors, and an increase in the number of apoptotic cells. We attribute this to a decrease in the stability of the modified Tuba1a transcript, and the absence of compensation by the other neurogenic tubulins. Our findings highlight the importance of maintaining the wild-type coding sequence when engineering mouse lines and the impact of synonymous genetic variation.


Assuntos
Códon , Tubulina (Proteína) , Animais , Camundongos , Códon/genética , Mutação , Fenótipo , RNA Mensageiro/genética , Tubulina (Proteína)/genética , Tubulina (Proteína)/metabolismo
11.
Environ Sci Pollut Res Int ; 30(13): 35646-35662, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36538224

RESUMO

Polycentric agglomeration has gradually become a salient feature of rapid growth in urbanization in China. Using province-level balanced panel data over the period 2000-18, we examine the impact of polycentric agglomeration on haze pollution and its mechanism of action. The results show that the impact of polycentric agglomeration on haze pollution exhibits a significant inverted U-shaped feature. Nevertheless, except for a few provinces where polycentric agglomeration exceeds the turning point, the degree of polycentric concentration in most provinces lies to the left of the turning point. Further, a mediating effect model illustrates that industrial structure rationalization and technological progress are effective paths through which polycentric agglomeration affects haze pollution. Finally, we demonstrate that the effect of polycentric agglomeration on haze pollution is influenced by transportation and communication infrastructure; improved transportation and communication infrastructure contributes to the haze control effect of polycentric agglomeration.


Assuntos
Poluição do Ar , Poluição do Ar/análise , Poluição Ambiental , China , Urbanização , Indústrias , Cidades , Desenvolvimento Econômico
12.
Sci Rep ; 12(1): 22156, 2022 12 22.
Artigo em Inglês | MEDLINE | ID: mdl-36550184

RESUMO

Although multisensory integration (MSI) has been extensively studied, the underlying mechanisms remain a topic of ongoing debate. Here we investigate these mechanisms by comparing MSI in healthy controls to a clinical population with spinal cord injury (SCI). Deafferentation following SCI induces sensorimotor impairment, which may alter the ability to synthesize cross-modal information. We applied mathematical and computational modeling to reaction time data recorded in response to temporally congruent cross-modal stimuli. We found that MSI in both SCI and healthy controls is best explained by cross-modal perceptual competition, highlighting a common competition mechanism. Relative to controls, MSI impairments in SCI participants were better explained by reduced stimulus salience leading to increased cross-modal competition. By combining traditional analyses with model-based approaches, we examine how MSI is realized during normal function, and how it is compromised in a clinical population. Our findings support future investigations identifying and rehabilitating MSI deficits in clinical disorders.


Assuntos
Traumatismos da Medula Espinal , Percepção Visual , Humanos , Percepção Visual/fisiologia , Percepção Auditiva/fisiologia , Estimulação Acústica , Tempo de Reação/fisiologia
13.
BMJ Open ; 12(10): e061954, 2022 10 11.
Artigo em Inglês | MEDLINE | ID: mdl-36220319

RESUMO

OBJECTIVES: The comparative clinical effectiveness of common surgical techniques to address long head of biceps (LHB) pathology is unclear. We synthesised the evidence to compare the clinical effectiveness of tenotomy versus tenodesis. DESIGN: A systematic review and meta-analysis using the Grading of Recommendations Assessment, Development and Evaluation approach. DATA SOURCES: EMBASE, Medline, PsycINFO and the Cochrane Library of randomised controlled trials were searched through 31 October 2021. ELIGIBILITY CRITERIA: We included randomised controlled trials, reporting patient reported outcome measures, comparing LHB tenotomy with tenodesis for LHB pathology, with or without concomitant rotator cuff pathology. Studies including patients treated for superior labral anterior-posterior tears were excluded. No language limits were employed. All publications from database inception to 31 October 2021 were included. DATA EXTRACTION AND SYNTHESIS: Screening was performed by two authors independently. A third author reviewed the article, where consensus for inclusion was required. Data were extracted by two authors. Data were synthesised using RevMan. Inverse variance statistics and a random effects model were used. RESULTS: 860 patients from 11 RCTs (426 tenotomy vs 434 tenodesis) were included. Pooled analysis of patient-reported functional outcome measures data demonstrated comparable outcomes (n=10 studies; 403 tenotomy vs 416 tenodesis; standardised mean difference (SMD): 0.14, 95% CI -0.04 to 0.32, p=0.13). There was no significant difference for pain (Visual Analogue Scale) (n=8 studies; 345 tenotomy vs 350 tenodesis; MD: -0.11, 95% CI -0.28 to 0.06, p=0.21). Tenodesis resulted in a lower rate of Popeye deformity (n=10 studies; 401 tenotomy vs 410 tenodesis; OR: 0.29, 95% CI 0.19 to 0.45, p<0.00001). Tenotomy demonstrated shorter operative time (n=4 studies; 204 tenotomy vs 201 tenodesis; MD 15.2, 95% CI 1.06 to 29.36, p<0.00001). CONCLUSIONS: Aside from a lower rate of cosmetic deformity, tenodesis yielded no significant clinical benefit to tenotomy for addressing LHB pathology. PROSPERO REGISTRATION NUMBER: CRD42020198658.


Assuntos
Lesões do Manguito Rotador , Tenodese , Artroscopia , Humanos , Manguito Rotador/cirurgia , Lesões do Manguito Rotador/cirurgia , Tenodese/métodos , Tenotomia/métodos , Resultado do Tratamento
14.
Cell Rep ; 40(9): 111253, 2022 08 30.
Artigo em Inglês | MEDLINE | ID: mdl-36044839

RESUMO

Activating KRAS mutations and functional loss of members of the SWI/SNF complex, including ARID1A, are found together in the primary liver tumor cholangiocarcinoma (CC). How these mutations cooperate to promote CC has not been established. Using murine models of hepatocyte and biliary-specific lineage tracing, we show that Kras and Arid1a mutations drive the formation of CC and tumor precursors from the biliary compartment, which are accelerated by liver inflammation. Using cultured cells, we find that Arid1a loss causes cellular proliferation, escape from cell-cycle control, senescence, and widespread changes in chromatin structure. Notably, we show that the biliary proliferative response elicited by Kras/Arid1a cooperation and tissue injury in CC is caused by failed engagement of the TGF-ß-Smad4 tumor suppressor pathway. We thus identify an ARID1A-TGF-ß-Smad4 axis as essential in limiting the biliary epithelial response to oncogenic insults, while its loss leads to biliary pre-neoplasia and CC.


Assuntos
Neoplasias dos Ductos Biliares , Colangiocarcinoma , Animais , Neoplasias dos Ductos Biliares/genética , Neoplasias dos Ductos Biliares/patologia , Ductos Biliares Intra-Hepáticos/metabolismo , Ductos Biliares Intra-Hepáticos/patologia , Colangiocarcinoma/genética , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Humanos , Camundongos , Mutação/genética , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Proteínas Proto-Oncogênicas p21(ras)/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Fator de Crescimento Transformador beta/metabolismo
15.
HardwareX ; 11: e00305, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35518277

RESUMO

We describe a complete open-source hardware/software solution for high performance thermostatted peptide fraction collection to support mass spectrometry experiments with complex proteomes. The instrument is easy to assemble using parts readily available through retail channels at a fraction of the cost compared to typical commercial systems. Control software is written in Python allowing for rapid customization. We demonstrate several useful applications, including the automated deposition of LC separated peptides for matrix-assisted laser desorption ionization mass spectrometry (MALDI-MS) as well as collection and concatenation of peptide fractions from nanoflow HPLC separations.

16.
Part Fibre Toxicol ; 19(1): 30, 2022 04 22.
Artigo em Inglês | MEDLINE | ID: mdl-35449069

RESUMO

BACKGROUND: Considering the expanding industrial applications of carbon nanotubes (CNTs), safety assessment of these materials is far less than needed. Very few long-term in vivo studies have been carried out. This is the first 2-year in vivo study to assess the effects of double walled carbon nanotubes (DWCNTs) in the lung and pleura of rats after pulmonary exposure. METHODS: Rats were divided into six groups: untreated, Vehicle, 3 DWCNT groups (0.12 mg/rat, 0.25 mg/rat and 0.5 mg/rat), and MWCNT-7 (0.5 mg/rat). The test materials were administrated by intratracheal-intrapulmonary spraying (TIPS) every other day for 15 days. Rats were observed without further treatment until sacrifice. RESULTS: DWCNT were biopersistent in the rat lung and induced marked pulmonary inflammation with a significant increase in macrophage count and levels of the chemotactic cytokines CCL2 and CCL3. In addition, the 0.5 mg DWCNT treated rats had significantly higher pulmonary collagen deposition compared to the vehicle controls. The development of carcinomas in the lungs of rats treated with 0.5 mg DWCNT (4/24) was not quite statistically higher (p = 0.0502) than the vehicle control group (0/25), however, the overall incidence of lung tumor development, bronchiolo-alveolar adenoma and bronchiolo-alveolar carcinoma combined, in the lungs of rats treated with 0.5 mg DWCNT (7/24) was statistically higher (p < 0.05) than the vehicle control group (1/25). Notably, two of the rats treated with DWCNT, one in the 0.25 mg group and one in the 0.5 mg group, developed pleural mesotheliomas. However, both of these lesions developed in the visceral pleura, and unlike the rats administered MWCNT-7, rats administered DWCNT did not have elevated levels of HMGB1 in their pleural lavage fluids. This indicates that the mechanism by which the mesotheliomas that developed in the DWCNT treated rats is not relevant to humans. CONCLUSIONS: Our results demonstrate that the DWCNT fibers we tested are biopersistent in the rat lung and induce chronic inflammation. Rats treated with 0.5 mg DWCNT developed pleural fibrosis and lung tumors. These findings demonstrate that the possibility that at least some types of DWCNTs are fibrogenic and tumorigenic cannot be ignored.


Assuntos
Neoplasias Pulmonares , Mesotelioma , Nanotubos de Carbono , Animais , Exposição por Inalação/efeitos adversos , Pulmão , Neoplasias Pulmonares/induzido quimicamente , Neoplasias Pulmonares/patologia , Mesotelioma/patologia , Nanotubos de Carbono/toxicidade , Pleura , Ratos
17.
Elife ; 112022 04 13.
Artigo em Inglês | MEDLINE | ID: mdl-35416151

RESUMO

Theories of prefrontal cortex (PFC) as optimizing reward value have been widely deployed to explain its activity in a diverse range of contexts, with substantial empirical support in neuroeconomics and decision neuroscience. Similar neural circuits, however, have also been associated with information processing. By using computational modeling, model-based functional magnetic resonance imaging analysis, and a novel experimental paradigm, we aim at establishing whether a dedicated and independent value system for information exists in the human PFC. We identify two regions in the human PFC that independently encode reward and information. Our results provide empirical evidence for PFC as an optimizer of independent information and reward signals during decision-making under realistic scenarios, with potential implications for the interpretation of PFC activity in both healthy and clinical populations.


Assuntos
Tomada de Decisões , Recompensa , Encéfalo/diagnóstico por imagem , Cognição , Humanos , Imageamento por Ressonância Magnética , Córtex Pré-Frontal
18.
Pediatr Dent ; 44(1): 45-54, 2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-35232536

RESUMO

Purpose: The purpose of this study was to investigate the interest in practice ownership among pediatric dentistry residents and influencing factors, particularly educational debt. Methods: An invitation to participate in an anonymous survey was sent to 933 pediatric dentistry residents training in the United States in the spring of 2020. Results: The survey response rate was 32.9 percent. Of the respondents, 61.2 percent reported being extremely or very interested in practice ownership and 49.8 percent anticipated becoming a practice owner within five years of graduation. An inverse relationship was seen between one's level of comfort in assuming a business loan to acquire a practice and having an educational debt burden of $400,000 or greater (P=0.002). Practice management preparation was the most common concern related to future practice ownership. Those feeling completely, very, or moderately prepared to manage a dental practice were over 40 percent more likely to be extremely or very interested in practice ownership than were those who felt slightly or not at all prepared (P<0.001). Conclusions: There appears to be broad interest in practice ownership among pediatric dentistry residents. Relatively high educational debt may negatively influence future practice ownership, but it may be less influential than other factors.


Assuntos
Intenção , Internato e Residência , Escolha da Profissão , Criança , Humanos , Propriedade , Odontopediatria/educação , Inquéritos e Questionários , Apoio ao Desenvolvimento de Recursos Humanos , Estados Unidos
19.
BMC Bioinformatics ; 23(1): 71, 2022 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-35164672

RESUMO

BACKGROUND: Degeneracy-the ability of structurally different elements to perform similar functions-is a property of many biological systems. Highly degenerate systems show resilience to perturbations and damage because the system can compensate for compromised function due to reconfiguration of the underlying network dynamics. Degeneracy thus suggests how biological systems can thrive despite changes to internal and external demands. Although degeneracy is a feature of network topologies and seems to be implicated in a wide variety of biological processes, research on degeneracy in biological networks is mostly limited to weighted networks. In this study, we test an information theoretic definition of degeneracy on random Boolean networks, frequently used to model gene regulatory networks. Random Boolean networks are discrete dynamical systems with binary connectivity and thus, these networks are well-suited for tracing information flow and the causal effects. By generating networks with random binary wiring diagrams, we test the effects of systematic lesioning of connections and perturbations of the network nodes on the degeneracy measure. RESULTS: Our analysis shows that degeneracy, on average, is the highest in networks in which ~ 20% of the connections are lesioned while 50% of the nodes are perturbed. Moreover, our results for the networks with no lesions and the fully-lesioned networks are comparable to the degeneracy measures from weighted networks, thus we show that the degeneracy measure is applicable to different networks. CONCLUSIONS: Such a generalized applicability implies that degeneracy measures may be a useful tool for investigating a wide range of biological networks and, therefore, can be used to make predictions about the variety of systems' ability to recover function.


Assuntos
Redes Reguladoras de Genes , Modelos Biológicos
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