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1.
Chromosoma ; 2023 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-37728741

RESUMO

Mitosis is an essential process in which the duplicated genome is segregated equally into two daughter cells. CTCF has been reported to be present in mitosis and has a role in localizing CENP-E, but its importance for mitotic fidelity remains to be determined. To evaluate the importance of CTCF in mitosis, we tracked mitotic behaviors in wild-type and two different CTCF CRISPR-based genetic knockdowns. We find that knockdown of CTCF results in prolonged mitoses and failed anaphase segregation via time-lapse imaging of SiR-DNA. CTCF knockdown did not alter cell cycling or the mitotic checkpoint, which was activated upon nocodazole treatment. Immunofluorescence imaging of the mitotic spindle in CTCF knockdowns revealed disorganization via tri/tetrapolar spindles and chromosomes behind the spindle pole. Imaging of interphase nuclei showed that nuclear size increased drastically, consistent with failure to divide the duplicated genome in anaphase. Long-term inhibition of CNEP-E via GSK923295 recapitulates CTCF knockdown abnormal mitotic spindles with polar chromosomes and increased nuclear sizes. Population measurements of nuclear shape in CTCF knockdowns do not display decreased circularity or increased nuclear blebbing relative to wild-type. However, failed mitoses do display abnormal nuclear morphologies relative to successful mitoses, suggesting that population images do not capture individual behaviors. Thus, CTCF is important for both proper metaphase organization and anaphase segregation which impacts the size and shape of the interphase nucleus likely through its known role in recruiting CENP-E.

2.
bioRxiv ; 2023 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-36712070

RESUMO

Mitosis is an essential process in which the duplicated genome is segregated equally into two daughter cells. CTCF has been reported to be present in mitosis but its importance for mitotic fidelity remains to be determined. To evaluate the importance of CTCF in mitosis, we tracked mitotic behaviors in wild type and two different CTCF CRISPR-based genetic knockdowns. We find that knockdown of CTCF results in prolonged mitoses and failed anaphase segregation via time lapse imaging of SiR-DNA. CTCF knockdown did not alter cell cycling or the mitotic checkpoint, which was activated upon nocodazole treatment. Immunofluorescence imaging of the mitotic spindle in CTCF knockdowns revealed disorganization via tri/tetrapolar spindles and chromosomes behind the spindle pole. Imaging of interphase nuclei showed that nuclear size increased drastically, consistent with failure to divide the duplicated genome in anaphase. Population measurements of nuclear shape in CTCF knockdowns do not display decreased circularity or increased nuclear blebbing relative to wild type. However, failed mitoses do display abnormal nuclear morphologies relative to successful mitoses, suggesting population images do not capture individual behaviors. Thus, CTCF is important for both proper metaphase organization and anaphase segregation which impacts the size and shape of the interphase nucleus.

3.
J Exerc Sci Fit ; 19(3): 204-208, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34276805

RESUMO

BACKGROUND/OBJECTIVE: Physical function, the ability of an individual to carry out physical tasks, is meaningfully related to health among older adults. Few studies have analyzed temporal trends in objective performance measures of physical function for older adults. The aim of this study was to estimate temporal trends in balance and walking speed for older Japanese adults (aged 65-79 years) between 1998 and 2018. METHODS: Annual, cross-sectional, national fitness surveillance data for balance (n = 114,785) and walking speed (n = 112,289) were reported descriptively by the Japanese Ministry of Education, Culture, Sports, Science and Technology across the 1998-2018 period. Trends in means were estimated by sample-weighted regression, with trends in variability estimated as the ratio of coefficients of variation. RESULTS: There was a moderate improvement in both mean balance (standardized effect size (ES) change (95% confidence interval (CI)): 0.50 (0.48-0.52)) and mean walking speed (ES change (95%CI): 0.53 (0.51-0.55)). Improvements were seen in all gender and age groups, with small gender-related and negligible age-related temporal differences. Variability declined substantially for both balance (ratio of CVs (95%CI): 0.77 (0.75-0.79)) and walking speed (ratio of CVs (95%CI): 0.87 (0.85-0.89)). CONCLUSION: Improved physical performance is suggestive of a corresponding improvement in health. Declines in variability indicate that temporal improvements were not uniform across the distribution.

4.
Genes (Basel) ; 12(6)2021 05 27.
Artigo em Inglês | MEDLINE | ID: mdl-34071789

RESUMO

Interphase chromatin, despite its appearance, is a highly organized framework of loops and bends. Chromosomes are folded into topologically associating domains, or TADs, and each chromosome and its homolog occupy a distinct territory within the nucleus. In Drosophila, genome organization is exceptional because homologous chromosome pairing is in both germline and somatic tissues, which promote interhomolog interactions such as transvection that can affect gene expression in trans. In this review, we focus on what is known about genome organization in Drosophila and discuss it from TADs to territory. We start by examining intrachromosomal organization at the sub-chromosome level into TADs, followed by a comprehensive analysis of the known proteins that play a key role in TAD formation and boundary establishment. We then zoom out to examine interhomolog interactions such as pairing and transvection that are abundant in Drosophila but rare in other model systems. Finally, we discuss chromosome territories that form within the nucleus, resulting in a complete picture of the multi-scale organization of the Drosophila genome.


Assuntos
Drosophila melanogaster/genética , Genoma de Inseto , Animais , Cromossomos de Insetos/genética
5.
Public Health Nurs ; 38(3): 464-469, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33368605

RESUMO

BACKGROUND: Since 2016, public health professionals in a rural, Midwest county have collaborated with competing health care organizations to establish electronic health record (EHR)-based systems for identifying patients with prediabetes and referring them to National Diabetes Prevention Program (NDPP) classes. The purpose of this program evaluation was to identify barriers and best practices learned from implementation in two rural health care organizations. METHODS: A purposively selected program coordinator from each organization and a primary care provider and information technology administrator from one of the organizations provided perspectives on initiating the referral process. Data were collected using open-ended questions in electronic survey format. Content analysis was used to identify themes. RESULTS: Two barrier themes were identified: Timely, clear communication is challenging; and More education is needed for both patients and providers. Best practice themes included Start small with one provider champion; Create a referral process that doesn't exceed resources; and Providers should be actively involved in referral discussions and decisions. CONCLUSION: Retrospective queries are a feasible way to initially establish EHR-based referral programs in rural areas. PHNs can facilitate this system change among competing health care organizations by leading partnerships, identifying common goals and timelines, and providing space for sharing challenges and best practices.


Assuntos
Diabetes Mellitus Tipo 2 , Estado Pré-Diabético , Diabetes Mellitus Tipo 2/prevenção & controle , Registros Eletrônicos de Saúde , Humanos , Encaminhamento e Consulta , Estudos Retrospectivos
6.
Front Plant Sci ; 10: 1643, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31998333

RESUMO

Examining factors that influence seedling establishment is essential for predicting the impacts of climate change on tree species' distributions. Seedlings originating from contrasting climates differentially express functional traits related to water and nutrient uptake and drought resistance that reflect their climate of origin and influence their responses to drought. Soil microbes may improve seedling establishment because they can enhance water and nutrient uptake and drought resistance. However, the relative influence of soil microbes on the expression of these functional traits between seedling families or populations from contrasting climates is unknown. To determine if soil microbes may differentially alter functional traits to enhance water and nutrient uptake and drought resistance between dry and wet families, seeds of loblolly pine families from the driest and wettest ends of its geographic range (dry, wet) were planted in sterilized sand (controls) or in sterilized sand inoculated with a soil microbial community (inoculated). Functional traits related to seedling establishment (germination), water and nutrient uptake and C allocation (root:shoot biomass ratio, root exudate concentration, leaf C:N, leaf N isotope composition (δ15N)), and drought resistance (turgor loss point, leaf carbon isotope composition (δ13C)) were measured. Then, plants were exposed to a drought treatment and possible shifts in photosynthetic performance were monitored using chlorophyll fluorescence. Inoculated plants exhibited significantly greater germination than controls regardless of family. The inoculation treatment significantly increased root:shoot biomass ratio in the wet family but not in the dry family, suggesting soil microbes alter functional traits that improve water and nutrient uptake more so in a family originating from a wetter climate than in a family originating from a drier climate. Microbial effects on photosynthetic performance during drought also differed between families, as photosynthetic performance of the dry inoculated group declined fastest. Regardless of treatment, the dry family exhibited a greater root:shoot biomass ratio, root exudate concentration, and leaf δ15N than the wet family. This indicates that the dry family allocated more resources belowground than the wet and the two family may have used different sources of plant available N, which may be related to their contrasting climates of origin and influence their drought resistance. Examination of variation in impacts of soil microbes on seedling physiology improves efforts to enhance seedling establishment and beneficial plant-microbe interactions under climate change.

7.
J Pharmacol Exp Ther ; 368(2): 282-291, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30409833

RESUMO

Fentanyl is an extremely potent synthetic opioid that has been increasingly used to adulterate heroin, cocaine, and counterfeit prescription pills, leading to an increase in opioid-induced fatal overdoses in the United States, Canada, and Europe. A vaccine targeting fentanyl could offer protection against the toxic effects of fentanyl in both recreational drug users and others in professions at risk of accidental exposure. This study focuses on the development of a vaccine consisting of a fentanyl-based hapten (F) conjugated to keyhole limpet hemocyanin (KLH) carrier protein or to GMP-grade subunit KLH (sKLH). Immunization with F-KLH in mice and rats reduced fentanyl-induced hotplate antinociception, and in rats reduced fentanyl distribution to the brain compared with controls. F-KLH did not reduce the antinociceptive effects of equianalgesic doses of heroin or oxycodone in rats. To assess the vaccine effect on fentanyl toxicity, rats immunized with F-sKLH or unconjugated sKLH were exposed to increasing subcutaneous doses of fentanyl. Vaccination with F-sKLH shifted the dose-response curves to the right for both fentanyl-induced antinociception and respiratory depression. Naloxone reversed fentanyl effects in both groups, showing that its ability to reverse respiratory depression was preserved. These data demonstrate preclinical selectivity and efficacy of a fentanyl vaccine and suggest that vaccines may offer a therapeutic option in reducing fentanyl-induced side effects.


Assuntos
Analgésicos Opioides/antagonistas & inibidores , Analgésicos Opioides/metabolismo , Fentanila/antagonistas & inibidores , Fentanila/metabolismo , Vacinas/farmacologia , Analgésicos Opioides/toxicidade , Animais , Bradicardia/sangue , Bradicardia/induzido quimicamente , Bradicardia/prevenção & controle , Fentanila/toxicidade , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Ratos , Ratos Sprague-Dawley , Insuficiência Respiratória/sangue , Insuficiência Respiratória/induzido quimicamente , Insuficiência Respiratória/prevenção & controle , Vacinas/uso terapêutico
8.
J Pharmacol Exp Ther ; 365(2): 346-353, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29535156

RESUMO

Heroin and oxycodone abuse occurs over a wide range of drug doses and by various routes of administration characterized by differing rates of drug absorption. The current study addressed the efficacy of a heroin vaccine [morphine hapten conjugated to keyhole limpet hemocyanin (M-KLH)] or oxycodone vaccine [oxycodone hapten conjugated to keyhole limpet hemocyanin (OXY-KLH)] for reducing drug distribution to brain after intravenous heroin or oxycodone, or subcutaneous oxycodone. Rats immunized with M-KLH or keyhole limpet hemocyanin (KLH) control received an intravenous bolus dose of 0.26 or 2.6 mg/kg heroin. Vaccination with M-KLH increased retention of heroin and its active metabolites 6-acetylmorphine (6-AM) and morphine in plasma compared with KLH controls, and reduced total opioid (heroin + 6-AM + morphine) distribution to brain but only at the lower heroin dose. Immunization also protected against respiratory depression at the lower heroin dose. Rats immunized with OXY-KLH or KLH control received 0.22 or 2.2 mg/kg oxycodone intravenously, the molar equivalent of the heroin doses. Immunization with OXY-KLH significantly reduced oxycodone distribution to brain after either oxycodone dose, although the magnitude of effect of immunization at the higher oxycodone dose was small (12%). By contrast, vaccination with OXY-KLH was more effective when oxycodone was administered subcutaneously rather than intravenously, reducing oxycodone distribution to brain by 44% after an oxycodone dose of 2.3 mg/kg. Vaccination also reduced oxycodone-induced antinociception. These data suggest that the efficacy of OXY-KLH and M-KLH opioid vaccines is highly dependent upon opioid dose and route of administration.


Assuntos
Heroína/administração & dosagem , Transtornos Relacionados ao Uso de Opioides/prevenção & controle , Oxicodona/administração & dosagem , Vacinas/farmacologia , Animais , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Relação Dose-Resposta a Droga , Vias de Administração de Medicamentos , Heroína/metabolismo , Heroína/farmacologia , Masculino , Oxicodona/metabolismo , Oxicodona/farmacologia , Ratos
9.
Int J Environ Res Public Health ; 13(2): 237, 2016 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-26907311

RESUMO

Tactical trainees, like those entering the police force, are required to undergo vigorous training as part of their occupational preparation. This training has the potential to cause injuries. In addition, the physical training, communal living and pressures of tactical training are known to induce immune suppression and have the potential to increase the risk of illness. The aim of this study was to investigate the relationship between leg power, as measured by a vertical jump (VJ), and rates of reported injuries and illnesses during police recruit training. Retrospective data from recruits (n = 1021) undergoing basic police recruit training at an Australian Police Force College was collected. Recruits completed a VJ assessment at the commencement of their second state of training. Formally reported illness and injuries were collected 12 weeks later, following completion of training. Correlations between VJ height and rates of reported illness and injury were low (r = -0.16 and -0.09, respectively) but significant (p < 0.005), with VJ height accounting for 2.6% and 0.8% of the variance in illness and injury rates, respectively. In terms of relative risks, recruits with the lowest recorded VJ heights were more than three times as likely as those with highest VJ heights to suffer injury and/or illness. Police recruits with lower VJ height are at a significantly greater risk of suffering an injury or illness during police basic recruit training.


Assuntos
Perna (Membro)/fisiologia , Força Muscular , Polícia , Ferimentos e Lesões/prevenção & controle , Adulto , Idoso , Austrália/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Medição de Risco , Ferimentos e Lesões/epidemiologia
10.
F1000Res ; 4: 32, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25767696

RESUMO

The construction and application of biological network models is an approach that offers a holistic way to understand biological processes involved in disease. Chronic obstructive pulmonary disease (COPD) is a progressive inflammatory disease of the airways for which therapeutic options currently are limited after diagnosis, even in its earliest stage. COPD network models are important tools to better understand the biological components and processes underlying initial disease development. With the increasing amounts of literature that are now available, crowdsourcing approaches offer new forms of collaboration for researchers to review biological findings, which can be applied to the construction and verification of complex biological networks. We report the construction of 50 biological network models relevant to lung biology and early COPD using an integrative systems biology and collaborative crowd-verification approach. By combining traditional literature curation with a data-driven approach that predicts molecular activities from transcriptomics data, we constructed an initial COPD network model set based on a previously published non-diseased lung-relevant model set. The crowd was given the opportunity to enhance and refine the networks on a website ( https://bionet.sbvimprover.com/) and to add mechanistic detail, as well as critically review existing evidence and evidence added by other users, so as to enhance the accuracy of the biological representation of the processes captured in the networks. Finally, scientists and experts in the field discussed and refined the networks during an in-person jamboree meeting. Here, we describe examples of the changes made to three of these networks: Neutrophil Signaling, Macrophage Signaling, and Th1-Th2 Signaling. We describe an innovative approach to biological network construction that combines literature and data mining and a crowdsourcing approach to generate a comprehensive set of COPD-relevant models that can be used to help understand the mechanisms related to lung pathobiology. Registered users of the website can freely browse and download the networks.

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