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1.
Curr Issues Mol Biol ; 46(6): 6267-6283, 2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38921045

RESUMO

Autoantibodies against apolipoprotein A-I (ApoA-I) are associated with cardiovascular disease risks. We aimed to examine the 4-hydroxy-2-nonenal (HNE) modification of ApoA-I in coronary artery disease (CAD) and evaluate the potential risk of autoantibodies against their unmodified and HNE-modified peptides. We assessed plasma levels of ApoA-I, HNE-protein adducts, and autoantibodies against unmodified and HNE-peptide adducts, and significant correlations and odds ratios (ORs) were examined. Two novel CAD-specific HNE-peptide adducts, ApoA-I251-262 and ApoA-I70-83, were identified. Notably, immunoglobulin G (IgG) anti-ApoA-I251-262 HNE, IgM anti-ApoA-I70-83 HNE, IgG anti-ApoA-I251-262, IgG anti-ApoA-I70-83, and HNE-protein adducts were significantly correlated with triglycerides, creatinine, or high-density lipoprotein in CAD with various degrees of stenosis (<30% or >70%). The HNE-protein adduct (OR = 2.208-fold, p = 0.020) and IgM anti-ApoA-I251-262 HNE (2.046-fold, p = 0.035) showed an increased risk of progression from >30% stenosis in CAD. HNE-protein adducts and IgM anti-ApoA-I251-262 HNE may increase the severity of CAD at high and low levels, respectively.

2.
Phys Chem Chem Phys ; 26(2): 788-807, 2024 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-38088777

RESUMO

Ultrafast excited-state dynamics of the simplest nitrostilbenes, namely trans-4-nitrostilbene (t-NSB), was studied in solvents of various polarities with ultrafast broadband time-resolved fluorescence and transient absorption spectroscopies, and by quantum-chemical computations. The results revealed that the initially excited S1(ππ*) state deactivation dynamics is strongly influenced by the solvent polarity. Specifically, the t-NSB S1-state lifetime decreases by three orders of magnitude from ∼60 ps in high-polarity solvents to ∼60 fs in nonpolar solvents. The strong solvent-polarity dependence arises from the differences in dipole moments among the S1 and relevant states, including the major intersystem crossing (ISC) receiver triplet states, and therefore, the solvent polarity can modulate their relative energies and ISC rates. In nonpolar solvents, the sub-100 fs lifetime is due to a combination of efficient ISC and internal conversion. In medium-polarity solvents, the S1-state population decays via a competing ISC relaxation mechanism in a biphasic manner, and the ISC rates are found to obey the inverse energy gap law of the strong coupling case. In high-polarity solvents, the S1 state is stabilized to a much lower energy such that ISC becomes energetically infeasible, and the S1 state decays via barrier crossing along the torsion angle of the central ethylenic bond to the nonfluorescent perpendicular configuration. Regardless of the initial S1-state deactivation pathways in various solvents, the excited-state population is ultimately trapped in the metastable T1-state perpendicular configuration, at which a slower ISC occurs to bring the system to the ground state and bifurcate into either trans or cis form of NSB.

3.
J Med Internet Res ; 26: e51069, 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-38289662

RESUMO

BACKGROUND: Sentiment analysis is a significant yet difficult task in natural language processing. The linguistic peculiarities of Cantonese, including its high similarity with Standard Chinese, its grammatical and lexical uniqueness, and its colloquialism and multilingualism, make it different from other languages and pose additional challenges to sentiment analysis. Recent advances in models such as ChatGPT offer potential viable solutions. OBJECTIVE: This study investigated the efficacy of GPT-3.5 and GPT-4 in Cantonese sentiment analysis in the context of web-based counseling and compared their performance with other mainstream methods, including lexicon-based methods and machine learning approaches. METHODS: We analyzed transcripts from a web-based, text-based counseling service in Hong Kong, including a total of 131 individual counseling sessions and 6169 messages between counselors and help-seekers. First, a codebook was developed for human annotation. A simple prompt ("Is the sentiment of this Cantonese text positive, neutral, or negative? Respond with the sentiment label only.") was then given to GPT-3.5 and GPT-4 to label each message's sentiment. GPT-3.5 and GPT-4's performance was compared with a lexicon-based method and 3 state-of-the-art models, including linear regression, support vector machines, and long short-term memory neural networks. RESULTS: Our findings revealed ChatGPT's remarkable accuracy in sentiment classification, with GPT-3.5 and GPT-4, respectively, achieving 92.1% (5682/6169) and 95.3% (5880/6169) accuracy in identifying positive, neutral, and negative sentiment, thereby outperforming the traditional lexicon-based method, which had an accuracy of 37.2% (2295/6169), and the 3 machine learning models, which had accuracies ranging from 66% (4072/6169) to 70.9% (4374/6169). CONCLUSIONS: Among many text analysis techniques, ChatGPT demonstrates superior accuracy and emerges as a promising tool for Cantonese sentiment analysis. This study also highlights ChatGPT's applicability in real-world scenarios, such as monitoring the quality of text-based counseling services and detecting message-level sentiments in vivo. The insights derived from this study pave the way for further exploration into the capabilities of ChatGPT in the context of underresourced languages and specialized domains like psychotherapy and natural language processing.


Assuntos
Inteligência Artificial , Povo Asiático , Comunicação , Idioma , Humanos , Conselheiros , Hong Kong , Modelos Lineares
4.
BMC Biol ; 21(1): 57, 2023 03 20.
Artigo em Inglês | MEDLINE | ID: mdl-36941675

RESUMO

BACKGROUND: Individual organisms may exhibit phenotypic plasticity when they acclimate to different conditions. Such plastic responses may facilitate or constrain the adaptation of their descendant populations to new environments, complicating their evolutionary trajectories beyond the genetic blueprint. Intriguingly, phenotypic plasticity itself can evolve in terms of its direction and magnitude during adaptation. However, we know little about what determines the evolution of phenotypic plasticity, including gene expression plasticity. Recent laboratory-based studies suggest dominance of reversing gene expression plasticity-plastic responses that move the levels of gene expression away from the new optima. Nevertheless, evidence from natural populations is still limited. RESULTS: Here, we studied gene expression plasticity and its evolution in the montane and lowland populations of an elevationally widespread songbird-the Rufous-capped Babbler (Cyanoderma ruficeps)-with reciprocal transplant experiments and transcriptomic analyses; we set common gardens at altitudes close to these populations' native ranges. We confirmed the prevalence of reversing plasticity in genes associated with altitudinal adaptation. Interestingly, we found a positive relationship between magnitude and degree of evolution in gene expression plasticity, which was pertinent to not only adaptation-associated genes but also the whole transcriptomes from multiple tissues. Furthermore, we revealed that genes with weaker expressional interactions with other genes tended to exhibit stronger plasticity and higher degree of plasticity evolution, which explains the positive magnitude-evolution relationship. CONCLUSIONS: Our experimental evidence demonstrates that species may initiate their adaptation to new habitats with genes exhibiting strong expression plasticity. We also highlight the role of expression interdependence among genes in regulating the magnitude and evolution of expression plasticity. This study illuminates how the evolution of phenotypic plasticity in gene expression facilitates the adaptation of species to challenging environments in nature.


Assuntos
Aclimatação , Adaptação Fisiológica , Fenótipo , Adaptação Fisiológica/genética , Altitude , Expressão Gênica , Evolução Biológica
5.
J Community Health Nurs ; 41(4): 265-272, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39149959

RESUMO

PURPOSE: To improve the quality of community health nursing practice, the learning outcomes of nursing students in community health nursing courses must be enhanced. Although the flipped classroom is considered an effective innovative teaching strategy, evidence of its application in community health nursing courses is limited. Therefore, this study aimed to examine the effects of a flipped classroom approach on community nursing competence, academic performance, course engagement, and learning satisfaction for a community health nursing course. DESIGN: A quasi-experimental study design was adopted between September 2021 and January 2022. METHODS: Two classes of nursing students (n = 92) from a 2-year nursing program at a university in Taiwan were recruited. The classes were randomly assigned to the intervention group (n = 50) that attended a flipped classroom and the control group (n = 42) that received traditional lecture-based instruction. FINDINGS: Compared with the control group, the intervention group demonstrated significantly greater improvements in community nursing competence (p = .012) and significantly higher academic performance (p = .005). In addition, the course engagement and learning satisfaction of the two groups were high, but not significantly different. CONCLUSIONS: A flipped classroom can be an important strategy to enhance community nursing competence and academic performance. CLINICAL EVIDENCE: The flipped classroom strategy can enhance community nursing competence of nursing students, which may improve the quality of population-based healthcare.


Assuntos
Enfermagem em Saúde Comunitária , Humanos , Enfermagem em Saúde Comunitária/educação , Taiwan , Feminino , Masculino , Bacharelado em Enfermagem/métodos , Estudantes de Enfermagem/psicologia , Estudantes de Enfermagem/estatística & dados numéricos , Aprendizagem Baseada em Problemas/métodos , Currículo , Adulto
6.
Artigo em Inglês | MEDLINE | ID: mdl-39257026

RESUMO

To comprehensively investigate the risk factors associated with depression, traditional Chinese medicine constitution (TCMC) has been found to be related to depression. However, the underlying mechanism remains unclear. This study examined the association between the concept of unbalanced TCMCs and major depressive disorder (MDD), investigated the overlapping polygenic risks between unbalanced TCMC and MDD, and performed a mediation test to establish potential pathways. In total, 11,030 individuals were recruited from the Taiwan Biobank, and the polygenic risk score (PRS) for MDD for each participant was calculated using the data from the Psychiatric Genomics Consortium. Unbalanced TCMC were classified as yang-deficiency, yin-deficiency, and stasis. The MDD PRS was associated with yang-deficiency odds ratio [OR] per standard deviation increase in standardized (PRS = 1.07, p = 0.0080), yin-deficiency (OR = 1.07, p = 0.0030), and stasis constitution (OR = 1.06, p = 0.0331). Yang-deficiency (OR = 2.07, p < 0.0001) and stasis constitutions (OR = 1.65, p = 0.0015) were associated with an increased risk of MDD. A higher number of unbalanced constitutions was associated with MDD (p < 0.0001). The effect of MDD PRS on MDD was partly mediated by yang-deficiency (10.21%) and stasis (8.41%) constitutions. This study provides evidence for the shared polygenic risk mechanism underlying depression and TCMC and the potential mediating role of TCMC in the polygenic liability for MDD.

7.
Mol Ecol ; 32(9): 2234-2251, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36748940

RESUMO

Organisms often acquire physiological and morphological modifications to conquer ecological challenges when colonizing new environments which lead to their adaptive evolution. However, deciphering the genomic mechanism of ecological adaptation is difficult because ecological environments are often too complex for straightforward interpretation. Thus, we examined the adaptation of a widespread songbird-the rufous-capped babbler (Cyanoderma ruficeps)-to a relatively simple system: distinct environments across elevational gradients on the mountainous island of Taiwan. We focused on the genomic sequences of 43 birds from five populations to show that the Taiwan group split from its sister group in mainland China around 1-2 million years ago (Ma) and colonized the montane habitats of Taiwan at least twice around 0.03-0.22 Ma. The montane and lowland Taiwan populations diverged with gene flow between them, suggesting strong selection associated with different elevations. We found that the montane babblers had smaller beaks than the lowland ones, consistent with Allen's rule, and identified candidate genes-COL9A1 and SOX11-underlying the beak size changes. We also found that altitudinally divergent mutations were mostly located in noncoding regions and tended to accumulate in chromosomal inversions and autosomes. The altitudinally divergent mutations might regulate genes related to haematopoietic, metabolic, immune, auditory and vision functions, as well as cerebrum morphology and plumage development. The results reveal the genomic bases of morphological and physiological adaptation in this species to the low temperature, hypoxia and high UV light environment at high elevation. These findings improve our understanding of how ecological adaptation drives population divergence from the perspective of genomic architecture.


Assuntos
Passeriformes , Aves Canoras , Animais , Aves Canoras/genética , Adaptação Fisiológica/genética , Genoma/genética , Genômica , Passeriformes/genética
8.
Proc Natl Acad Sci U S A ; 116(6): 2152-2157, 2019 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-30659151

RESUMO

What kind of genetic variation contributes the most to adaptation is a fundamental question in evolutionary biology. By resequencing genomes of 80 individuals, we inferred the origin of genomic variants associated with a complex adaptive syndrome involving multiple quantitative traits, namely, adaptation between high and low altitudes, in the vinous-throated parrotbill (Sinosuthora webbiana) in Taiwan. By comparing these variants with those in the Asian mainland population, we revealed standing variation in 24 noncoding genomic regions to be the predominant genetic source of adaptation. Parrotbills at both high and low altitudes exhibited signatures of recent selection, suggesting that not only the front but also the trailing edges of postglacial expanding populations could be subjected to environmental stresses. This study verifies and quantifies the importance of standing variation in adaptation in a cohort of genes, illustrating that the evolutionary potential of a population depends significantly on its preexisting genetic diversity. These findings provide important context for understanding adaptation and conservation of species in the Anthropocene.


Assuntos
Adaptação Biológica , Evolução Biológica , Variação Genética , Aves Canoras/genética , Animais , Meio Ambiente , Genética Populacional , Genoma , Genômica/métodos , Polimorfismo de Nucleotídeo Único , RNA não Traduzido , Seleção Genética , Taiwan
9.
Chemistry ; 27(71): 17725, 2021 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-34897838

RESUMO

Invited for the cover of this issue are Chin-Wei Lu, Zu-Po Yang, Hai-Ching Su, and co-workers at National Yang Ming Chiao Tung University and Providence University. The image depicts electron transport for light-emitting electrochemical cells. Read the full text of the article at 10.1002/chem.202103739.

10.
Chemistry ; 27(71): 17785-17793, 2021 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-34747069

RESUMO

Recently, perovskites have attracted intense attention due to their high potential in optoelectronic applications. Employing perovskites as the emissive materials of light-emitting electrochemical cells (LECs) shows the advantages of simple fabrication process, low-voltage operation, and compatibility with inert electrodes, along with saturated electroluminescence (EL) emission. Unlike in previously reported perovskite LECs, in which salts are incorporated in the emissive layer, the ion-transport layer was separated from the emissive layer in this work. The layer of ionic transition metal complex (iTMC) not only provides mobile ions but also serves as an electron-injection/transport layer. Orthogonal solvents are used in spin coating to prevent the intermixing of stacked perovskite and iTMC layers. The blue iTMC with high ionization potential is effective in blocking holes from the emissive layer and thus ensures EL color saturation. In addition, the carrier balance of the perovskite/iTMC LECs can be optimized by adjusting the iTMC layer thickness. The optimized external quantum efficiency of the CsPbBr3 /iTMC LEC reaches 6.8 %, which is among the highest reported values for perovskite LECs. This work successfully demonstrates that, compared with mixing all components in a single emissive layer, separating the layer of ion transport, electron injection and transport from the perovskite emissive layer is more effective in adjusting device carrier balance. As such, solution-processable perovskite/iTMC LECs open up a new way to realize efficient perovskite LECs.

11.
J Med Internet Res ; 23(12): e30135, 2021 12 20.
Artigo em Inglês | MEDLINE | ID: mdl-34932008

RESUMO

BACKGROUND: Clinical mobility and balance assessments identify older adults who have a high risk of falls in clinics. In the past two decades, sensors have been a popular supplement to mobility and balance assessment to provide quantitative information and a cost-effective solution in the community environment. Nonetheless, the current sensor-based balance assessment relies on manual observation or motion-specific features to identify motions of research interest. OBJECTIVE: The objective of this study was to develop an automatic motion data analytics framework using signal data collected from an inertial sensor for balance activity analysis in community-dwelling older adults. METHODS: In total, 59 community-dwelling older adults (19 males and 40 females; mean age = 81.86 years, SD 6.95 years) were recruited in this study. Data were collected using a body-worn inertial measurement unit (including an accelerometer and a gyroscope) at the L4 vertebra of each individual. After data preprocessing and motion detection via a convolutional long short-term memory (LSTM) neural network, a one-class support vector machine (SVM), linear discriminant analysis (LDA), and k-nearest neighborhood (k-NN) were adopted to classify high-risk individuals. RESULTS: The framework developed in this study yielded mean accuracies of 87%, 86%, and 89% in detecting sit-to-stand, turning 360°, and stand-to-sit motions, respectively. The balance assessment classification showed accuracies of 90%, 92%, and 86% in classifying abnormal sit-to-stand, turning 360°, and stand-to-sit motions, respectively, using Tinetti Performance Oriented Mobility Assessment-Balance (POMA-B) criteria by the one-class SVM and k-NN. CONCLUSIONS: The sensor-based approach presented in this study provided a time-effective manner with less human efforts to identify and preprocess the inertial signal and thus enabled an efficient balance assessment tool for medical professionals. In the long run, the approach may offer a flexible solution to relieve the community's burden of continuous health monitoring.


Assuntos
Vida Independente , Equilíbrio Postural , Idoso , Idoso de 80 Anos ou mais , Algoritmos , Feminino , Humanos , Masculino , Medição de Risco
12.
Front Zool ; 17: 14, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32426018

RESUMO

BACKGROUND: Obligate brood parasites exert strong selective pressure on target hosts. In response, hosts typically evolve anti-parasitism strategies, of which egg recognition is one of the most efficient. Generally, host egg-recognition capacity is determined using model eggs. Previous studies have shown that some host species, which are capable of detecting parasite eggs, do not reject model eggs. However, it is unknown that whether the reaction to model eggs varies among distinct populations of the same host in relation to the degree of parasitism pressure. RESULTS: Here, we compared the rejection frequencies of model eggs and real eggs between mainland and island populations of the plain prinia (Prinia inornata), which are respectively sympatric and allopatric with their brood parasite, the common cuckoo (Cuculus canorus). Our results indicated that the mainland and island populations rejected real eggs at similar rates, but rejected model eggs, which were similar in size to real eggs but heavier, at significantly different rates: the island population rejected fewer model eggs, possibly because the rejection motivation of this population was lower due to absence of parasitism. CONCLUSIONS: Our results indicated that some factors affecting the decision to reject, such as rejection motivation, varied according to the degree of parasitism pressure, and thus influenced the frequency of egg rejection. Furthermore, our results suggested that model eggs should be used with caution in comparative studies of egg recognition abilities among species or populations subjected to different intensities of brood parasitism. That is, model eggs may fail to accurately detect egg recognition in host populations with little to no risk of parasitism.

13.
Telemed J E Health ; 25(12): 1189-1197, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-30601109

RESUMO

Background: Sleep is related to various kinds of health outcomes. Many studies traditionally collect data on sleep using questionnaires or sleep diaries. An increasing popular alternative is a wrist-worn device. The accuracy of these devices is uncertain, and assessment of this accuracy is important.Introduction: The purpose of this study is to compare consensus sleep diary (CSD) and an actigraphy-based wrist-worn device (Fitbit Alta™ [Fitbit, San Francisco, CA]) measurements of total sleep time (TST), sleep onset latency, wake time after sleep onset, number of awakenings, and sleep efficiency.Materials and Methods: Ten healthy young adults (50% female, 100% Asian) in the age range between 20 to 24 years old wore a Fitbit Alta around their nondominated hand during seven consecutive nights. The participants also filled in a CSD every day.Results: On average, the wrist-worn device (Fitbit Alta) recorded a TST per night of 437.15 min, which is 5.46 min shorter on average than the CSD recorded (442.61 min). Bland-Altman plots indicate that there is large variance in the sleep recorded between Fitbit™ (Fitbit, San Francisco, CA) and CSD. For example, Fitbit recorded 2.15 more awakenings per night than CSD, which is equal to 13.09 min on average longer wake time after sleep onset.Conclusion: Fitbit and CSD show significant differences in recording sleep. We find that for most sleep metrics, the level of disagreement is small enough for the devices to be interchangeably used except for recording wakes during the night.


Assuntos
Actigrafia/instrumentação , Sono/fisiologia , Dispositivos Eletrônicos Vestíveis , Feminino , Voluntários Saudáveis , Hong Kong , Humanos , Masculino , Punho , Adulto Jovem
14.
Angew Chem Int Ed Engl ; 57(17): 4622-4626, 2018 04 16.
Artigo em Inglês | MEDLINE | ID: mdl-29461658

RESUMO

The combination of conventional transition-metal-catalyzed coupling (2 e- process) and photoredox catalysis (1 e- process) has emerged as a powerful approach to catalyze difficult cross-coupling reactions under mild reaction conditions. Reported is a palladium carbodicarbene (CDC) complex that mediates both a Suzuki-Miyaura coupling and photoredox catalysis for C-N bond formation upon visible-light irradiation. These two catalytic pathways can be combined to promote both conventional transition-metal-catalyzed coupling and photoredox catalysis to mediate C-H arylation under ambient conditions with a single catalyst in an efficient one-pot process.

15.
J Anim Ecol ; 84(3): 829-839, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25582865

RESUMO

Niche evolution underpins the generation and maintenance of biological diversity, but niche conservatism, in which niches remain little changed over time in closely related taxa, and the role of ecology in niche evolution are continually debated. To test whether climate niches are conserved in two closely related passerines in East Asia - the vinous-throated (Paradoxornis webbianus) and ashy-throated (P. alphonsianus) parrotbills - we established their potential allopatric and sympatric regions using ecological niche models and compared differences in their climate niches using niche overlap indices in background tests and multivariate statistical analyses. We also used polymorphism data on 44 nuclear genes to infer their divergence demography. We found that these two parrotbills occupy different climate niches, in both their allopatric and potential sympatric regions. Because the potential sympatric region is the area predicted to be suitable for both parrotbills based on the ecological niche models, it can serve as a natural common garden. Therefore, their observed niche differences in this potential sympatry were not simply rendered by phenotypic plasticity and probably had a genetic basis. Our genetic analyses revealed that the two parrotbills are not evolutionarily independent for the most recent part of their divergence history. The two parrotbills diverged c. 856,000 years ago and have had substantial gene flow since a presumed secondary contact c. 290,000 years ago. This study provides an empirical case demonstrating that climate niches may not be homogenized in nascent species in spite of substantial, ongoing gene flow, which in turn suggests a role for ecology in promoting and maintaining diversification among incipient species.


Assuntos
Clima , Fluxo Gênico , Passeriformes/genética , Animais , Ecossistema , Feminino , Especiação Genética , Masculino , Dados de Sequência Molecular , Passeriformes/classificação , Filogenia
16.
Cell Physiol Biochem ; 33(2): 513-27, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24557000

RESUMO

BACKGROUND/AIMS: Intermittent hypoxia (IH) may exert pre-conditioning-like cardioprotective effects and alter Ca(2+) regulation; however, the exact mechanism of these effects remains unclear. Thus, we examined Ca(2+)-handling mechanisms induced by IH in rat neonatal cardiomyocytes. METHODS: Cardiomyocytes were exposed to repetitive hypoxia-re-oxygenation cycles for 1-4 days. Mitochondrial reactive oxygen species (ROS) generation was determined by flow cytometry, and intracellular Ca(2+) concentrations were measured using a live-cell fluorescence imaging system. Protein kinase C (PKC) isoforms and Ca(2+)-handling proteins were analysed using immunofluorescence and western blotting. RESULTS: After IH exposure for 4 days, the rate of Ca(2+) extrusion from the cytosol to the extracellular milieu during 40-mM KCl-induced Ca(2+) mobilization increased significantly, whereas ROS levels increased mildly. IH activated PKC isoforms, which translocated to the membrane from the cytosol, and Na(+)/Ca(2+) exchanger-1, leading to enhanced Ca(2+) efflux capacity. Simultaneously, IH increased sarcoplasmic reticulum (SR) Ca(2+)-ATPase and ryanodine receptor 2 (RyR-2) activities and RyR-2 expression, resulting in improved Ca(2+) uptake and release capacity of SR in cardiomyocytes. CONCLUSIONS: IH-induced mild elevations in ROS generation can enhance Ca(2+) efflux from the cytosol to the extracellular milieu and Ca(2+)-mediated SR regulation in cardiomyocytes, resulting in enhanced Ca(2+)-handling ability.


Assuntos
Sinalização do Cálcio , Cálcio/metabolismo , Miócitos Cardíacos/metabolismo , Estresse Oxidativo , Espécies Reativas de Oxigênio/metabolismo , Animais , Hipóxia Celular , Células Cultivadas , Miócitos Cardíacos/patologia , Ratos , Ratos Sprague-Dawley
17.
J Anim Ecol ; 83(2): 450-9, 2014 03.
Artigo em Inglês | MEDLINE | ID: mdl-24107232

RESUMO

The niche variation hypothesis (NVH) predicts that populations with wider niches are phenotypically more variable than populations with narrower niches, which is frequently used to explain diversifying processes such as ecological release. However, not all empirical evidence supports the NVH. Furthermore, a relationship between population phenotypic variation and niche width can be caused by sexual selection or environmental gradients, which should be carefully considered along with competition in explaining niche variation. In this study, we used eight populations of a generalist passerine species, Paradoxornis webbianus (vinous-throated parrotbill), to test the NVH. We assessed evidence of ecological sexual dimorphism and environmental gradients in bill morphology of P. webbianus. A total of 170 P. webbianus from eight sites ranging 24-2668 m in altitude were included in this study. We used two principal components to quantify bill morphology: one describes bill size and the other describes bill slenderness. We used stable carbon and nitrogen isotope values of bird feathers to quantify trophic positions, and we estimated population trophic niche width using Bayesian standardized ellipse area. Paradoxornis webbianus with larger and more slender bills fed at higher trophic levels and population trophic niche width tended to increase with bill-size variation, supporting the NVH. The males had larger bills and marginally higher nitrogen isotope values than the females, suggesting ecological sexual dimorphism. Despite a positive correlation between bill size and wing length indicating sexual selection for larger male size, only three of the eight populations showed both male-biased bill size and male-biased wing length. Sexual dimorphism explained 13%-64% of bill-size variation across sites, suggesting its role in niche variation could vary greatly among populations. The variation in bill slenderness in P. webbianus increased with elevation. However, neither bill-size variation nor trophic niche width changed with elevation. Therefore, environmental gradients that could be reflected in the elevation are not likely to drive the observed morphological and niche variation. This study provides an empirical case for the NVH and highlights the importance of investigating sexual dimorphism and environmental gradients in studies of niche dynamics.


Assuntos
Bico/anatomia & histologia , Ecossistema , Estado Nutricional , Aves Canoras/anatomia & histologia , Aves Canoras/fisiologia , Animais , Feminino , Masculino , Caracteres Sexuais , Taiwan
18.
Naturwissenschaften ; 101(9): 727-34, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25011416

RESUMO

Parasites may, in multi-parasite systems, block the defenses of their hosts and thus thwart host recognition of parasites by frequency-dependent selection. Nest defenses as frontline may block or promote the subsequent stage of defenses such as egg recognition. We conducted comparative studies of the defensive strategies of a host of the Oriental cuckoo Cuculus optatus, the yellow-bellied prinia Prinia flaviventris, in mainland China with multiple species of cuckoos and in Taiwan with a single cuckoo species. Cuckoo hosts did not exhibit aggression toward cuckoos in the presence of multiple cuckoo species but showed strong aggressive defenses of hosts directed toward cuckoos in Taiwan. Furthermore, the cuckoo host in populations with a single cuckoo species was able to distinguish adults of its brood parasite, the Oriental cuckoo, from adult common cuckoos (Cuculus canorus). This represents the first case in which a cuckoo host has been shown to specifically distinguish Oriental cuckoo, from other Cuculus species. Hosts ejected eggs at a higher rate in a single cuckoo species system than in a multi-species cuckoo system, which supports the strategy facilitation hypothesis. Granularity analysis of variation in egg phenotype based on avian vision modeling supported the egg signature hypothesis in hosts because Taiwanese prinias increased consistency in the appearance of their eggs within individual hosts thus favoring efficient discrimination against cuckoo eggs. This study significantly improves our knowledge of intraspecific variation in antiparasitism behavior of hosts between single- and multi-cuckoo systems.


Assuntos
Aves/fisiologia , Interações Hospedeiro-Parasita , Comportamento de Nidação/fisiologia , Óvulo/fisiologia , Animais , China , Passeriformes/parasitologia , Fenótipo , Taiwan
19.
J Affect Disord ; 346: 31-39, 2024 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-37866734

RESUMO

BACKGROUND: Marriage has long been considered protective against suicide, but shifting social norms since 2000 in Hong Kong raise doubts regarding whether this is still the case. The aim of the study was to investigate the changing association between suicide and marital status. METHODS: Official suicide data for 2002-2020 in Hong Kong were obtained. Suicide rates and suicide risk ratios were calculated by gender, age group, and marital status (married, never-married, widowed, divorced/separated). RESULTS: Suicide risk decreased significantly over time for men and women of all ages. People who were never-married, divorced/separated, had significantly higher suicide risks than their married counterparts. Increasing suicide risks over time were observed for never-married men aged 20-49 years, never-married women aged 35-49 years, and divorced/separated men aged 20-34 years. Widowed men and women of any age had higher suicide risks compared with previous studies in Hong Kong. LIMITATIONS: Marital status is a time-varying covariate, and the time spent in a given marital status could affect suicide risk. Some age and gender subgroups had much smaller sample sizes than others, thus it is possible that our suicide risk estimates were overestimated. CONCLUSIONS: Despite rapidly social changing in Hong Kong during the study period, marriage remains a strong protective factor against suicide for men and women. The protective effect is particularly evident for younger people. Increasing suicide rates for divorced/separated, never-married, or widowed people suggest that they require more psychosocial support.


Assuntos
Casamento , Suicídio , Masculino , Feminino , Humanos , Fatores de Proteção , Hong Kong/epidemiologia , Estado Civil , Divórcio
20.
Clin Cardiol ; 47(3): e24247, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38450794

RESUMO

BACKGROUND: Previous studies show that using 12-lead electrocardiogram (ECG) or 24-h ECG monitor for the detection of cardiac arrhythmia events in patients with stroke or syncope is ineffective. HYPOTHESIS: The 14-day continuous ECG patch has higher detection rates of arrhythmias compared with conventional 24-h ECG monitoring in patients with ischemic stroke or syncope. METHODS: This cross-sectional study of patients with newly diagnosed ischemic stroke or syncope received a 24-h ECG monitoring and 14-day continuous cardiac monitoring patch and the arrhythmia events were measured. RESULTS: This study enrolled 83 patients with ischemic stroke or syncope. The detection rate of composite cardiac arrhythmias was significantly higher for the 14-day ECG patch than 24-h Holter monitor (69.9% vs. 21.7%, p = .006). In patients with ischemic stroke, the detection rates of cardiac arrhythmias were 63.4% for supraventricular tachycardia (SVT), 7% for ventricular tachycardia (VT), 5.6% for atrial fibrillation (AF), 4.2% for atrioventricular block (AVB), and 1.4% for pause by 14-day ECG patch, respectively. The significant difference in arrhythmic detection rates were found for SVT (45.8%), AF (6%), pause (1.2%), AVB (2.4%), and VT (9.6%) by 14-day ECG patch but not by 24-h Holter monitor in patients with ischemic stroke or syncope. CONCLUSIONS: A 14-day ECG patch can be used on patients with ischemic stroke or syncope for the early detection of AF or other cardiac arrhythmia events. The patch can be helpful for physicians in planning medical or mechanical interventions of patients with ischemic stroke and occult AF.


Assuntos
Fibrilação Atrial , Bloqueio Atrioventricular , AVC Isquêmico , Taquicardia Ventricular , Humanos , Estudos Transversais , Síncope/diagnóstico , Síncope/etiologia , Eletrocardiografia
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