Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 88
Filtrar
Mais filtros

Tipo de documento
Intervalo de ano de publicação
1.
Ecol Lett ; 26(2): 245-256, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36573288

RESUMO

Although it is well established that density dependence drives changes in organismal abundance over time, relatively little is known about how density dependence affects variation in abundance over space. We tested the hypothesis that spatial trade-offs between food and safety can change the drivers of population distribution, caused by opposing patterns of density-dependent habitat selection (DDHS) that are predicted by the multidimensional ideal free distribution. We addressed this using winter aerial survey data of northern Yellowstone elk (Cervus canadensis) spanning four decades. Supporting our hypothesis, we found positive DDHS for food (herbaceous biomass) and negative DDHS for safety (openness and roughness), such that the primary driver of habitat selection switched from food to safety as elk density decreased from 9.3 to 2.0 elk/km2 . Our results demonstrate how population density can drive landscape-level shifts in population distribution, confounding habitat selection inference and prediction and potentially affecting community-level interactions.


Assuntos
Cervos , Lobos , Animais , Ecossistema , Densidade Demográfica , Comportamento Predatório , Estações do Ano , Parques Recreativos , Noroeste dos Estados Unidos
2.
BMC Psychiatry ; 23(1): 511, 2023 07 14.
Artigo em Inglês | MEDLINE | ID: mdl-37452292

RESUMO

BACKGROUND: Due to its high pervasiveness and adversarial consequences, postpartum anxiety has been one of the most worrying public health concerns in the last decade. According to previous research, the occurrence of mental disorders among women in the postpartum period upsurges significantly in the course of universal disasters. The Postpartum Specific Anxiety Scale - Research Short Form - for use in global Crises [PSAS-IR-RSF-C] has not been used in Iran for postpartum women during a health system shock. Consequently, this study was conducted to determine the validity and reliability of the Persian version (PSAS-IR-RSF-C) during the COVID-19 pandemic. METHODS: This cross-sectional study was performed with 180 women who were between six weeks and six months after delivery, by random sampling method from December 2021 to June 2022. The validity of the PSAS-RSF-C in terms of face, content, was analyzed, and the construct validity was assessed using exploratory and confirmatory factor analyses. Internal consistency and test-retest reliability of the questionnaire were measured using (Cronbach's alpha, McDonald's ω) and intraclass correlation coefficient (ICC), respectively. RESULTS: The content validity index and content validity ratio of the Persian version of the PSAS-IR-RSF-C were 0.96 and 0.98, respectively. A three-factor structure was extracted during the exploratory factor analysis process, and model validity was confirmed by the values of fit indices. Cronbach's alpha coefficient, McDonald's ω and intra-cluster correlation coefficient (95% confidence interval) were 0.74, 0.92 (0.78 to 0.93) and 0.97 (0.93 to 0.98), respectively. CONCLUSIONS: For the specific assessment of postpartum anxiety among Iranian women during crises, the Persian version of the PSAS-IR-RSF-C is a valid and reliable tool.


Assuntos
COVID-19 , Pandemias , Humanos , Feminino , Irã (Geográfico) , Psicometria/métodos , Reprodutibilidade dos Testes , Estudos Transversais , Período Pós-Parto , Ansiedade/diagnóstico , Inquéritos e Questionários
3.
BMC Pregnancy Childbirth ; 23(1): 531, 2023 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-37480013

RESUMO

BACKGROUND: The increasing prevalence of postpartum anxiety as a common psychological problem affects a large part of women's lives. Despite the existence of tools in this field, but due to the lack of specificity in reflecting postpartum anxiety, it is necessary to have a specific tool to screen it. Since the psychometric evaluation of the Postpartum Specific Anxiety Scale-Research Short-Form (PSAS-RSF) among Iranian women has not been assessed in Iran until now, so we decided to conduct this study with the aim of psychometric evaluation of the PSAS-IR-RSF. METHODS: We included 180 women (six weeks to six months postpartum) in the study by random sampling during the period from December 2021 to June 2022. We examined the validity of the PSAS-IR-RSF tool in terms of face, content and construct (through exploratory and confirmatory factor analyses). We used internal consistency and test-retest reliability to determine the reliability of the scale. RESULTS: In the present study, content validity index (CVI) and content validity ratio (CVR) of the PSAS-IR-RSF tool were equal to 0.91 and 0.97, respectively. We extracted a four-factor structure through the process of exploratory factor analysis. The values of fitting indices confirmed the validity of the model. Cronbach's alpha coefficient was equal to 0.72 and intra-class correlation coefficient (with 95% confidence interval) was 0.97 (0.98 to 0.93). CONCLUSIONS: The Persian version of the PSAS-IR-RSF is a valid and reliable tool for the specific evaluation of postpartum anxiety among Iranian women.


Assuntos
Ansiedade , Período Pós-Parto , Humanos , Feminino , Irã (Geográfico) , Psicometria , Reprodutibilidade dos Testes , Ansiedade/diagnóstico
4.
Am J Primatol ; 85(7): e23505, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37157167

RESUMO

Sleep is an important aspect of great ape life; these animals build sleeping platforms every night. In a community of chimpanzees, each subgroup selects a sleeping site where each individual builds a sleeping platform, mostly on a tree. Previous studies have measured the heights of sleeping platforms and sleeping trees to test the predation avoidance and thermoregulation hypotheses of sleeping site selection. However, it remains unclear how components of vegetation structure (vertical and horizontal) together determine the selection of sleeping sites by chimpanzees. Using botanical inventories around sleeping sites in a tropical rainforest of Cameroon, we found that chimpanzees preferentially sleep in trees measuring 40-50 cm in diameter. Regarding height, on average, sleeping trees measured 26 m and sleeping platforms were built at 16 m. To build sleeping platforms, chimpanzees preferred four tree species, which represent less than 3% of tree species in the study area. We demonstrate that the variation in abundance of tree species and the vertical and horizontal structure of the vegetation drive chimpanzee sleeping site selection. It was previously thought that preference for vegetation types was the driver of sleeping site selection in chimpanzees. However, results from this study indicate that the importance of vegetation types in sleeping site selection depends on their botanical characteristics including the variation in tree size, the abundance of all trees, the abundance of sleeping trees, and the occurrence of preferred sleeping tree species, which predict sleeping site selection. The height and diameter of trees are considered by chimpanzees when selecting a particular tree for sleeping and when selecting a site with a specific vertical structure. In addition to tree height, the abundance of smaller neighboring trees may also play a role in the chimpanzee antipredation strategy. Our results demonstrate that chimpanzees consider several vegetation parameters to establish sleeping sites.


Assuntos
Comportamento de Nidação , Pan troglodytes , Animais , Pan troglodytes/fisiologia , Comportamento de Nidação/fisiologia , Árvores , Sono , Comportamento Predatório
5.
Ecol Appl ; 32(4): e2568, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35138667

RESUMO

Oral baiting is used to deliver vaccines to wildlife to prevent, control, and eliminate infectious diseases. A central challenge is how to spatially distribute baits to maximize encounters by target animal populations, particularly in urban and suburban areas where wildlife such as raccoons (Procyon lotor) are abundant and baits are delivered along roads. Methods from movement ecology that quantify movement and habitat selection could help to optimize baiting strategies by more effectively targeting wildlife populations across space. We developed a spatially explicit, individual-based model of raccoon movement and oral rabies vaccine seroconversion to examine whether and when baiting strategies that match raccoon movement patterns perform better than currently used baiting strategies in an oral rabies vaccination zone in greater Burlington, Vermont, USA. Habitat selection patterns estimated from locally radio-collared raccoons were used to parameterize movement simulations. We then used our simulations to estimate raccoon population rabies seroprevalence under currently used baiting strategies (actual baiting) relative to habitat selection-based baiting strategies (habitat baiting). We conducted simulations on the Burlington landscape and artificial landscapes that varied in heterogeneity relative to Burlington in the proportion and patch size of preferred habitats. We found that the benefits of habitat baiting strongly depended on the magnitude and variability of raccoon habitat selection and the degree of landscape heterogeneity within the baiting area. Habitat baiting improved seroprevalence over actual baiting for raccoons characterized as habitat specialists but not for raccoons that displayed weak habitat selection similar to radiocollared individuals, except when baits were delivered off roads where preferred habitat coverage and complexity was more pronounced. In contrast, in artificial landscapes with either more strongly juxtaposed favored habitats and/or higher proportions of favored habitats, habitat baiting performed better than actual baiting, even when raccoons displayed weak habitat preferences and where baiting was constrained to roads. Our results suggest that habitat selection-based baiting could increase raccoon population seroprevalence in urban-suburban areas, where practical, given the heterogeneity and availability of preferred habitat types in those areas. Our novel simulation approach provides a flexible framework to test alternative baiting strategies in multiclass landscapes to optimize bait-distribution strategies.


Assuntos
Vacina Antirrábica , Raiva , Administração Oral , Animais , Animais Selvagens , Raiva/epidemiologia , Raiva/prevenção & controle , Raiva/veterinária , Guaxinins , Estudos Soroepidemiológicos , Vacinação/métodos , Vacinação/veterinária
6.
Neuroimage ; 238: 118259, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34118395

RESUMO

Since tau PET tracers were introduced, investigators have quantified them using a wide variety of automated methods. As longitudinal cohort studies acquire second and third time points of serial within-person tau PET data, determining the best pipeline to measure change has become crucial. We compared a total of 415 different quantification methods (each a combination of multiple options) according to their effects on a) differences in annual SUVR change between clinical groups, and b) longitudinal measurement repeatability as measured by the error term from a linear mixed-effects model. Our comparisons used MRI and Flortaucipir scans of 97 Mayo Clinic study participants who clinically either: a) were cognitively unimpaired, or b) had cognitive impairments that were consistent with Alzheimer's disease pathology. Tested methods included cross-sectional and longitudinal variants of two overarching pipelines (FreeSurfer 6.0, and an in-house pipeline based on SPM12), three choices of target region (entorhinal, inferior temporal, and a temporal lobe meta-ROI), five types of partial volume correction (PVC) (none, two-compartment, three-compartment, geometric transfer matrix (GTM), and a tau-specific GTM variant), seven choices of reference region (cerebellar crus, cerebellar gray matter, whole cerebellum, pons, supratentorial white matter, eroded supratentorial WM, and a composite of eroded supratentorial WM, pons, and whole cerebellum), two choices of region masking (GM or GM and WM), and two choices of statistic (voxel-wise mean vs. median). Our strongest findings were: 1) larger temporal-lobe target regions greatly outperformed entorhinal cortex (median sample size estimates based on a hypothetical clinical trial were 520-526 vs. 1740); 2) longitudinal processing pipelines outperformed cross-sectional pipelines (median sample size estimates were 483 vs. 572); and 3) reference regions including supratentorial WM outperformed traditional cerebellar and pontine options (median sample size estimates were 370 vs. 559). Altogether, our results favored longitudinally SUVR methods and a temporal-lobe meta-ROI that includes adjacent (juxtacortical) WM, a composite reference region (eroded supratentorial WM + pons + whole cerebellum), 2-class voxel-based PVC, and median statistics.


Assuntos
Encéfalo/diagnóstico por imagem , Carbolinas , Tomografia por Emissão de Pósitrons/métodos , Proteínas tau/metabolismo , Idoso , Idoso de 80 Anos ou mais , Encéfalo/metabolismo , Encéfalo/patologia , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade
7.
Angiogenesis ; 24(3): 533-548, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33496909

RESUMO

Myxofibrosarcoma is genetically complex and lacks effective nonsurgical treatment strategies; thus, elucidation of novel molecular drivers is urgently needed. Reanalyzing public myxofibrosarcoma datasets, we identified mRNA upregulation and recurrent gain of RSF1 and characterized this chromatin remodeling gene. Myxofibrosarcoma cell lines were employed to elucidate the oncogenic mechanisms of RSF1 by genetic manipulation and two IL-1ß-neutralizing antibodies (RD24, P2D7KK), highlighting the regulatory basis and targetability of downstream IL-1ß-mediated angiogenesis. Tumor samples were assessed for RSF1, IL-1ß, and microvascular density (MVD) by immunohistochemistry and for RSF1 gene status by FISH. In vivo, RSF1-silenced and P2D7KK-treated xenografts were analyzed for tumor-promoting effects and the IL-1ß-linked therapeutic relevance of RSF1, respectively. In vitro, RSF1 overexpression promoted invasive and angiogenic phenotypes with a stronger proangiogenic effect. RT-PCR profiling identified IL1B as a top-ranking candidate upregulated by RSF1. RSF1 required hSNF2H and CEBP/ß to cotransactivate the IL1B promoter, which increased the IL1B mRNA level, IL-1ß secretion and angiogenic capacity. Angiogenesis induced by RSF1-upregulated IL-1ß was counteracted by IL1B knockdown and both IL-1ß-neutralizing antibodies. Clinically, RSF1 overexpression was highly associated with RSF1 amplification, IL-1ß overexpression, increased MVD and higher grades (all P ≤ 0.01) and independently predicted shorter disease-specific survival (P = 0.019, hazard ratio: 4.556). In vivo, both RSF1 knockdown and anti-IL-1ß P2D7KK (200 µg twice weekly) enabled significant growth inhibition and devascularization in xenografts. In conclusion, RSF1 overexpression, partly attributable to RSF1 amplification, contributes a novel proangiogenic function by partnering with CEBP/ß to cotransactivate IL1B, highlighting its prognostic, pathogenetic, and therapeutic relevance in myxofibrosarcomas.


Assuntos
Adenosina Trifosfatases/metabolismo , Proteína beta Intensificadora de Ligação a CCAAT/metabolismo , Proteínas Cromossômicas não Histona/metabolismo , Fibrossarcoma/metabolismo , Amplificação de Genes , Regulação Neoplásica da Expressão Gênica , Interleucina-1beta/metabolismo , Proteínas de Neoplasias/metabolismo , Neovascularização Patológica/metabolismo , Proteínas Nucleares/biossíntese , Transativadores/biossíntese , Adenosina Trifosfatases/genética , Proteína beta Intensificadora de Ligação a CCAAT/genética , Proteínas Cromossômicas não Histona/genética , Fibrossarcoma/irrigação sanguínea , Fibrossarcoma/genética , Fibrossarcoma/patologia , Humanos , Interleucina-1beta/genética , Proteínas de Neoplasias/genética , Neovascularização Patológica/genética , Proteínas Nucleares/genética , Transativadores/genética
8.
Cancer Cell Int ; 21(1): 315, 2021 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-34147108

RESUMO

RSF1, remodelling and spacing factor 1, is an important interphase centromere protein and is overexpressed in many types of cancers and correlated with poor overall survival. RSF1 has functions mainly in maintaining chromosome stability, facilitating DNA repair, maintaining the protein homeostasis of RSF1 and suppressing the transcription of some oncogenes when RSF1 protein is expressed at an optimal level; however, RSF1 overexpression facilitates drug resistance and cell cycle checkpoint inhibition to prompt cancer proliferation and survival. The RSF1 expression level and gene background are crucial for RSF1 functions, which may explain why RSF1 has different functions in different cancer types. This review summarizes the functional domains of RSF1, the overexpression status of RSF1 and SNF2H in cancer based on the TCGA and GTEX databases, the cancer-related functions of RSF1 in interacting with H2Aub, HDAC1, CENP-A, PLK1, ATM, CENP-S, SNF2H, HBX, BubR1, cyclin E1, CBP and NF-κB and the potential clinical value of RSF1, which will lay a theoretical foundation for the structural biology study of RSF1 and application of RSF1 inhibitors, truncated RSF1 proteins and SNF2H inhibitors in the treatment of RSF1-overexpressing tumours.

9.
Biol Res ; 54(1): 11, 2021 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-33757583

RESUMO

BACKGROUND: Atherosclerosis (AS) is the most common type in cardiovascular disease. Due to its complex pathogenesis, the exact etiology of AS is unclear. circRNA has been shown to play an essential role in most diseases. However, the underlying mechanism of circRNA in AS has been not understood clearly. METHODS: Quantitative Real-Time PCR assay was used to detect the expression of circRSF1, miR-135b-5p and histone deacetylase 1 (HDAC1). Western blot was applied to the measure of protein expression of HDAC1, B-cell lymphoma-2 (Bcl-2), BCL2-associated X (Bax), cleaved-caspase-3, vascular cell adhesion molecule 1 (VCAM1), intercellular cell adhesion molecule-1 (ICAM1) and E-selectin. MTT assay and flow cytometry were used to detect cell proliferation and apoptosis, respectively. Dual luciferase reporter assay and RIP assay was used to determine the relationship among circRSF1, miR-135b-5p and HDAC1. Besides, an ELISA assay was performed to measure the levels of IL-1ß, IL-6, TNF-α and IL-8. RESULTS: In this study, ox-LDL inhibited circRSF1 and HDAC1 expression while upregulated miR-135b-5p expression in Human umbilical vein endothelial cells (HUVECs). Importantly, ox-LDL could inhibit HUVECs growth. Moreover, promotion of circRSF1 or inhibition of miR-135b-5p induced cell proliferation while inhibited apoptosis and inflammation of ox-LDL-treated HUVECs, which was reversed by upregulating miR-135b-5p or downregulating HDCA1 in ox-LDL-treated HUVECs. More than that, we verified that circRSF1 directly targeted miR-135b-5p and HDAC1 was a target mRNA of miR-135b-5p in HUVECs. CONCLUSION: CircRSF1 regulated ox-LDL-induced vascular endothelial cell proliferation, apoptosis and inflammation through modulating miR-135b-5p/HDAC1 axis in AS, providing new perspectives and methods for the treatment and diagnosis of AS.


Assuntos
Aterosclerose , MicroRNAs , Apoptose/genética , Aterosclerose/genética , Proliferação de Células , Histona Desacetilase 1/genética , Células Endoteliais da Veia Umbilical Humana , Humanos , Inflamação/genética , Lipoproteínas LDL , MicroRNAs/genética , Proteínas Nucleares , RNA Circular , Transativadores
10.
J Anim Ecol ; 89(12): 2777-2787, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32961607

RESUMO

Despite being widely used, habitat selection models are rarely reliable and informative when applied across different ecosystems or over time. One possible explanation is that habitat selection is context-dependent due to variation in consumer density and/or resource availability. The goal of this paper is to provide a general theoretical perspective on the contributory mechanisms of consumer and resource density-dependent habitat selection, as well as on our capacity to account for their effects. Towards this goal we revisit the ideal free distribution (IFD), where consumers are assumed to be omniscient, equally competitive and freely moving, and are hence expected to instantaneously distribute themselves across a heterogeneous landscape such that fitness is equalised across the population. Although these assumptions are clearly unrealistic to some degree, the simplicity of the structure in IFD provides a useful theoretical vantage point to help clarify our understanding of more complex spatial processes. Of equal importance, IFD assumptions are compatible with the assumptions underlying common habitat selection models. Here we show how a fitness-maximising space use model, based on IFD, gives rise to resource and consumer density-dependent shifts in consumer distribution, providing a mechanistic explanation for the context-dependent outcomes often reported in habitat selection analysis. Our model suggests that adaptive shifts in consumer distribution patterns would be expected to lead to nonlinear and often non-monotonic patterns of habitat selection. These results indicate that even under the simplest of assumptions about adaptive organismal behaviour, habitat selection strength should critically depend on system-wide characteristics. Clarifying the impact of adaptive behavioural responses may be pivotal in making meaningful ecological inferences about observed patterns of habitat selection and allow reliable transferability of habitat selection predictions across time and space.


Assuntos
Ecossistema , Animais
11.
Proc Natl Acad Sci U S A ; 114(38): E7949-E7958, 2017 09 19.
Artigo em Inglês | MEDLINE | ID: mdl-28855339

RESUMO

Posttranslational histone modifications play important roles in regulating chromatin-based nuclear processes. Histone H2AK119 ubiquitination (H2Aub) is a prevalent modification and has been primarily linked to gene silencing. However, the underlying mechanism remains largely obscure. Here we report the identification of RSF1 (remodeling and spacing factor 1), a subunit of the RSF complex, as a H2Aub binding protein, which mediates the gene-silencing function of this histone modification. RSF1 associates specifically with H2Aub, but not H2Bub nucleosomes, through a previously uncharacterized and obligatory region designated as ubiquitinated H2A binding domain. In human and mouse cells, genes regulated by RSF1 overlap significantly with those controlled by RNF2/Ring1B, the subunit of Polycomb repressive complex 1 (PRC1) which catalyzes the ubiquitination of H2AK119. About 82% of H2Aub-enriched genes, including the classic PRC1 target Hox genes, are bound by RSF1 around their transcription start sites. Depletion of H2Aub levels by Ring1B knockout results in a significant reduction of RSF1 binding. In contrast, RSF1 knockout does not affect RNF2/Ring1B or H2Aub levels but leads to derepression of H2Aub target genes, accompanied by changes in H2Aub chromatin organization and release of linker histone H1. The action of RSF1 in H2Aub-mediated gene silencing is further demonstrated by chromatin-based in vitro transcription. Finally, RSF1 and Ring1 act cooperatively to regulate mesodermal cell specification and gastrulation during Xenopus early embryonic development. Taken together, these data identify RSF1 as a H2Aub reader that contributes to H2Aub-mediated gene silencing by maintaining a stable nucleosome pattern at promoter regions.


Assuntos
Inativação Gênica/fisiologia , Histonas/metabolismo , Proteínas Nucleares/metabolismo , Nucleossomos/metabolismo , Transativadores/metabolismo , Ubiquitinação/fisiologia , Animais , Células HeLa , Histonas/genética , Humanos , Camundongos , Proteínas Nucleares/genética , Nucleossomos/genética , Complexo Repressor Polycomb 1/genética , Complexo Repressor Polycomb 1/metabolismo , Regiões Promotoras Genéticas/fisiologia , Transativadores/genética , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo
12.
Ecol Lett ; 22(9): 1417-1427, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31240840

RESUMO

Increasing interest in the complexity, variation and drivers of movement-related behaviours promise new insight into fundamental components of ecology. Resolving the multidimensionality of spatially explicit behaviour remains a challenge for investigating tactics and their relation to niche construction, but high-resolution movement data are providing unprecedented understanding of the diversity of spatially explicit behaviours. We introduce a framework for investigating individual variation in movement-defined resource selection that integrates the behavioural and ecological niche concepts. We apply it to long-term tracking data of 115 African elephants (Loxodonta africana), illustrating how a behavioural hypervolume can be defined based on differences between individuals and their ecological settings, and applied to explore population heterogeneity. While normative movement behaviour is frequently used to characterise population behaviour, we demonstrate the value of leveraging heterogeneity in the behaviour to gain greater insight into population structure and the mechanisms driving space-use tactics.


Assuntos
Comportamento Animal , Ecossistema , Elefantes , Atividade Motora , Animais , Sistemas de Informação Geográfica , Quênia
13.
BMC Cardiovasc Disord ; 19(1): 54, 2019 03 05.
Artigo em Inglês | MEDLINE | ID: mdl-30836958

RESUMO

BACKGROUND: The retrievable stent filter (RSF) has been previously used for the treatment of vena cava thrombosis. In this study, the RSF was implanted to treat aortic thrombosis and then withdrawn. CASE PRESENTATION: A 47-years-old woman presented with severe abdominal pain and fever. Computed tomography showed massive mural thrombosis in the thoracic and abdominal aorta complicated by portal venous thrombosis. The RSF was implanted, a transjugular intrahepatic portosystemic stent shunt was established and a thrombolytic catheter was inserted for portal vein thrombolysis. The aortic thrombus was successfully compressed and fixed without thrombosis. After 15 days, abdominal pain had ceased, the abdominal aortic thrombus was mostly dissolved and the RSF was retrieved. Catheter angiography confirmed the recovery of portal vein thrombosis. CONCLUSIONS: The RSF was able to compress and fix aortic thrombus without the usual complications of stenting after removal.


Assuntos
Doenças da Aorta/terapia , Procedimentos Endovasculares/instrumentação , Veia Porta , Derivação Portossistêmica Transjugular Intra-Hepática , Stents , Terapia Trombolítica , Trombose/terapia , Trombose Venosa/terapia , Doenças da Aorta/complicações , Doenças da Aorta/diagnóstico por imagem , Remoção de Dispositivo , Feminino , Humanos , Pessoa de Meia-Idade , Veia Porta/diagnóstico por imagem , Trombose/complicações , Trombose/diagnóstico por imagem , Resultado do Tratamento , Trombose Venosa/diagnóstico por imagem , Trombose Venosa/etiologia
14.
Proteins ; 86(6): 621-628, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29493006

RESUMO

The secondary structure transitions of regenerated silk fibroin (RSF) under different external perturbations have been studied extensively, except for pressure. In this work, time-resolved infrared spectroscopy with the attenuated total reflectance (ATR) accessory was employed to follow the secondary structure transitions of RSF in its wet film under low pressure. It has been found that pressure alone is favorable only to the formation of ß-sheet structure. Under constant pressure there is an optimum amount of D2 O in the wet film (D2 O : film = 2:1) so as to provide the optimal condition for the reorganization of the secondary structure and to have the largest formation of ß-sheet structure. Under constant amount of D2 O and constant pressure, the secondary structure transitions of RSF in its wet film can be divided into three stages along with time. In the first stage, random coil, α-helix, and ß-turn were quickly transformed into ß-sheet. In the second stage, random coil and ß-turn were relatively slowly transformed into ß-sheet and α-helix, and the content of α-helix was recovered to the value prior to the application of pressure. In the third and final stage, no measurable changes can be found for each secondary structure. This study may be helpful to understand the secondary structure changes of silk fibroin in silkworm's glands under hydrostatic pressure.


Assuntos
Bombyx/química , Fibroínas/química , Pressão , Animais , Cinética , Estrutura Secundária de Proteína , Espectroscopia de Infravermelho com Transformada de Fourier
15.
Cell Physiol Biochem ; 44(6): 2322-2336, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29258089

RESUMO

BACKGROUND/AIMS: The therapeutic efficacy of paclitaxel is hampered by chemotherapeutic resistance in non-small cell lung cancer (NSCLC). Rsf-1 enhanced paclitaxel resistance via nuclear factor-κB (NF-κB) in ovarian cancer cells and nasopharyngeal carcinoma. This study assessed the function of Rsf-1 in the modulation of the sensitivity of NSCLC to paclitaxel via the NF-κB pathway. METHODS: The mRNA and protein levels of the related genes were quantified by RT-PCR and Western blotting. Rsf-1 silencing was achieved with CRISPR/Cas9 gene editing. Cell cycle, migration and proliferation were tested with flow cytometry, transwell test and CCK8 test. Cell apoptosis was analyzed with flow cytometry and quantification of C-capase3. The parameters of the tumors were measured in H460 cell xenograft mice. RESULTS: Rsf-1 was highly expressed in H460 and H1299 cells. Rsf-1 knockout caused cell arrest at the G1 phase, increased cell apoptosis, and decreased migration and cell proliferation. Rsf-1 knockout increased the inhibition of cell proliferation, the reduction in cell migration and the augment in cell apoptosis in paclitaxel treated H460 and H1299 cells. Rsf-1 knockout further enhanced the paclitaxel-mediated decrease in the volume and weight of the tumors in H460 cell xenograft mice. Helenalin and Rsf-1 knockout decreased the protein levels of p-P65, BcL2, CFLAR, and XIAP; hSNF2H knockout decreased the protein level of NF-κB p-P65 without altering Rsf-1 and p65 protein levels, while Rsf-1 and hSNF2H double knockout decreased the level of NF-κB p-P65, in H1299 and H460 cells. CONCLUSION: These results demonstrate that Rsf-1 influences the sensitivity of NSCLC to paclitaxel via regulation of the NF-κB pathway and its downstream genes.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Resistencia a Medicamentos Antineoplásicos , Neoplasias Pulmonares/tratamento farmacológico , NF-kappa B/metabolismo , Proteínas Nucleares/genética , Paclitaxel/farmacologia , Transativadores/genética , Animais , Antineoplásicos Fitogênicos/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , Linhagem Celular Tumoral , Feminino , Técnicas de Inativação de Genes , Humanos , Pulmão/efeitos dos fármacos , Pulmão/metabolismo , Pulmão/patologia , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Camundongos Nus , Proteínas Nucleares/metabolismo , Paclitaxel/uso terapêutico , Transdução de Sinais , Transativadores/metabolismo
16.
Molecules ; 22(9)2017 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-28869563

RESUMO

Radix Sophorae Flavescentis (RSF) and Fructus Cnidii (FC) compose a typical herbal synergic pair in traditional Chinese medicine (TCM) for pruritus symptom treatments. The mechanisms of action for the synergy are not understood. This paper aims at predicting the anti-pruritus targets and the main active ingredients for the RSF and FC herbal pair. We demonstrate that the RSF-FC herbal pair can be elucidated by mining the chemical structures of compounds derived from RSF and FC. Based on chemical structure data, the putative targets for RSF and FC were predicted. Additional putative targets that interact with the anti-pruritus targets were derived by mapping the putative targets onto a PPI network. By examining the annotations of these proteins, we conclude that (1) RSF's active compounds are mainly alkaloids and flavonoids. The representative putative targets of the alkaloids are inflammation-related proteins (MAPK14, PTGS2, PTGS2, and F2) and pruritus-related proteins (HRH1, TRPA1, HTR3A, and HTR6). The representative putative targets of the flavonoids are inflammation-related proteins (TNF, NF-κB, F2, PTGS2, and PTGS2) and pruritus-related proteins (NR3C1 and IL2). (2) FC's active compounds are mainly coumarins. Their representative putative targets are CNS-related proteins (AChE and OPRK1) and inflammation-related proteins (PDE4D, TLR9, and NF-κB). (3) Both RSF and FC display anti-inflammatory effects, though they exhibit their anti-pruritus effects in different ways. Their synergy shows that RSF regulates inflammation-related pruritus and FC regulates CNS-related pruritus.


Assuntos
Antipruriginosos/farmacologia , Medicamentos de Ervas Chinesas/farmacologia , Prurido/tratamento farmacológico , Alcaloides/química , Alcaloides/farmacologia , Alcaloides/uso terapêutico , Antipruriginosos/química , Antipruriginosos/uso terapêutico , Cumarínicos/química , Sinergismo Farmacológico , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/uso terapêutico , Flavonoides/química , Flavonoides/farmacologia , Flavonoides/uso terapêutico , Humanos , Estrutura Molecular , Prurido/metabolismo , Relação Estrutura-Atividade
17.
Plasmid ; 81: 21-6, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26021570

RESUMO

The original pBAD24 plasmid and the derived lower copy number (the pBAD322 series) expression vectors have been widely used in Escherichia coli, Salmonella enterica, and related bacteria. However, a flexible pBAD expression system has been available only in pMB1 (ColE1) vectors. We report a series of pBAD vectors that replicate using the origin of plasmid RSF1030 that are compatible with pMB1 (ColE1) and p15A (pACYC) vectors. Both high (≥pBAD24) and medium (~pBAD322) copy number plasmids encoding resistance to ampicillin, chloramphenicol, kanamycin, tetracycline, spectinomycin/streptomycin, gentamycin, or trimethoprim are available.


Assuntos
Arabinose/farmacologia , Escherichia coli/genética , Dosagem de Genes , Regulação Bacteriana da Expressão Gênica/efeitos dos fármacos , Vetores Genéticos/genética , Plasmídeos/genética , Clonagem Molecular , Instabilidade Genômica
18.
Acta Crystallogr F Struct Biol Commun ; 80(Pt 6): 125-134, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38818823

RESUMO

The RSF complex belongs to the ISWI chromatin-remodeling family and is composed of two subunits: RSF1 (remodeling and spacing factor 1) and SNF2h (sucrose nonfermenting protein 2 homolog). The RSF complex participates in nucleosome spacing and assembly, and subsequently promotes nucleosome maturation. Although SNF2h has been extensively studied in the last few years, the structural and functional properties of the remodeler RSF1 still remain vague. Here, a cryo-EM structure of the RSF-nucleosome complex is reported. The 3D model shows a two-lobe architecture of RSF, and the structure of the RSF-nucleosome (flanked with linker DNA) complex shows that the RSF complex moves the DNA away from the histone octamer surface at the DNA-entry point. Additionally, a nucleosome-sliding assay and a restriction-enzyme accessibility assay show that the RSF1 subunit may cause changes in the chromatin-remodeling properties of SNF2h. As a `nucleosome ruler', the results of an RSF-dinucleosome binding affinity test led to the proposal that the critical distance that RSF `measures' between two nucleosomes is about 24 base pairs.


Assuntos
Montagem e Desmontagem da Cromatina , Microscopia Crioeletrônica , Proteínas de Ligação a DNA , Nucleossomos , Microscopia Crioeletrônica/métodos , Nucleossomos/química , Nucleossomos/metabolismo , Nucleossomos/ultraestrutura , Proteínas de Ligação a DNA/química , Proteínas de Ligação a DNA/metabolismo , Modelos Moleculares , Ligação Proteica , Proteínas Nucleares/química , Proteínas Nucleares/metabolismo , Proteínas Nucleares/genética , DNA/química , DNA/metabolismo , Histonas/química , Histonas/metabolismo , Histonas/genética , Humanos , Fatores de Transcrição/química , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genética , Adenosina Trifosfatases , Proteínas Cromossômicas não Histona , Transativadores
19.
Int J Biol Macromol ; 272(Pt 2): 132830, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38825264

RESUMO

Artificial graft serves as the primary grafts used in the clinical management of sports-related injuries. Until now, optimizing its graft-host integration remains a great challenge due to the excessive inflammatory response during the inflammatory phase, coupled with an absence of tissue-inductive capacity during the regeneration phase. Here, a multi-layered regenerated silk fibroin (RSF) coating loaded with curcumin (Cur) and Zn2+ on the surface of the PET grafts (Cur@Zn2+@PET) was designed and fabricated for providing time-matched regulation specifically tailored to address issues arising at both inflammatory and regeneration phases, respectively. The release of Cur and Zn2+ from the Cur@Zn2+@PET followed a time-programmed pattern in vitro. Specifically, cellular assays revealed that Cur@Zn2+@PET initially released Cur during the inflammatory phase, thereby markedly inhibit the expression of inflammatory cytokines TNF-a and IL-1ß. Meanwhile, a significant release of Zn2+ was major part during the regeneration phase, serving to induce the osteogenic differentiation of rBMSC. Furthermore, rat model of anterior cruciate ligament reconstruction (ACLR) showed that through time-programmed drug release, Cur@Zn2+@PET could suppress the formation of fibrous interface (FI) caused by inflammatory response, combined with significant new bone (NB) formation during regeneration phase. Consequently, the implementation of the Cur@Zn2+@PET characterized by its time-programmed release patterns hold considerable promise for improving graft-host integration for sports-related injuries.


Assuntos
Curcumina , Fibroínas , Zinco , Curcumina/farmacologia , Curcumina/química , Animais , Zinco/química , Zinco/farmacologia , Ratos , Fibroínas/química , Fibroínas/farmacologia , Liberação Controlada de Fármacos , Materiais Revestidos Biocompatíveis/química , Materiais Revestidos Biocompatíveis/farmacologia , Masculino , Osteogênese/efeitos dos fármacos , Ratos Sprague-Dawley
20.
Front Public Health ; 12: 1427546, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39145178

RESUMO

Objective: This study aimed to evaluate the association between six complete blood count (CBC)-derived inflammatory markers [neutrophil-to-lymphocyte ratio (NLR), monocyte-to-lymphocyte ratio (MLR), platelet-to-lymphocyte ratio (PLR), systemic immune-inflammatory index (SII), systemic inflammatory response index (SIRI), and pan-immune inflammation value (PIV)] and the risk of frailty and mortality. Methods: Data were obtained from the National Health and Nutrition Examination Survey (NHANES) 1999-2018. Mortality was identified using the National Death Index until December 31, 2019. Multiple logistic regression analysis was conducted to evaluate the association between six CBC-derived inflammatory markers and frailty. The Cox regression model assessed the association between six CBC-derived inflammatory markers and mortality in frail populations. Restricted cubic spline (RCS) was used to visualize the association of the six CBC-derived inflammatory markers with mortality risk. The predictive value of CBC-derived inflammatory markers for mortality was further assessed using a random survival forest (RSF) approach. Results: This study analyzed data from a total of 16,705 middle-aged and older participants. Among them, 6,503 participants were frail, with a mortality rate of 41.47%. Multiple logistic regression analysis showed that NLR, MLR, PLR, SII, SIRI, and PIV were positively associated with frailty risk. The Cox regression model revealed that participants in the highest quartile had a significantly increased risk of death compared to those in the lowest quartile: NLR (HR = 1.73, 95% CI:1.54, 1.94), MLR (HR = 1.71, 95% CI:1.51, 1.93), PLR (HR = 1.28, 95%CI: 1.15, 1.43), SII (HR = 1.50, 95%CI:1.34, 1.68), SIRI (HR = 1.88, CI 95%:1.67, 2.12), PIV (HR = 1.55, 95%CI:1.38, 1.73). Random survival forest (RSF) analyses demonstrated that MLR had the highest predictive value for mortality risk middle-aged and older adult frail participants. Conclusion: The results suggest that CBC-derived inflammatory markers are associated with a higher risk of frailty as well as mortality in the middle and old-aged population of the United States.


Assuntos
Biomarcadores , Fragilidade , Inflamação , Inquéritos Nutricionais , Humanos , Masculino , Feminino , Fragilidade/sangue , Fragilidade/mortalidade , Pessoa de Meia-Idade , Idoso , Biomarcadores/sangue , Inflamação/sangue , Contagem de Células Sanguíneas/estatística & dados numéricos , Idoso de 80 Anos ou mais , Idoso Fragilizado/estatística & dados numéricos , Fatores de Risco , Mortalidade
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA