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1.
iScience ; 27(5): 109578, 2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38638573

RESUMO

In this study, a method was developed to create oxygen vacancies in Cu2O/TiO2 heterojunctions. By varying the amounts of ethylenediaminetetraacetic acid (EDTA), sodium citrate, and copper acetate, Cu2O/TiO2 with different Cu ratios were synthesized. Tests on CO2 photocatalytic reduction revealed that Cu2O/TiO2's performance is influenced by Cu content. The ideal Cu mass fraction in Cu2O/TiO2, determined by inductively coupled plasma (ICP), is between 0.075% and 0.55%, with the highest CO yield being 10.22 µmol g-1 h-1, significantly surpassing pure TiO2. High-resolution transmission electron microscopy and electron paramagnetic resonance studies showed optimal oxygen vacancy in the most effective heterojunction. Density functional theory (DFT) calculations indicated a 0.088 eV lower energy barrier for ∗CO2 to ∗COOH conversion in Cu2O/TiO2 with oxygen vacancy compared to TiO2, suggesting that oxygen vacancies enhance photocatalytic activity.

2.
Mol Med Rep ; 29(4)2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38426568

RESUMO

Subsequently to the publication of the above article, an interested reader drew to the authors' attention that two pairs of data panels featured in Figs. 2E and 6D, portraying the results from cell invasion and migration assay experiments, appeared to contain overlapping sections, such that data which were intended to show the results from differently performed experiments had apparently been derived from a smaller number of original sources. The authors were able to re­examine their original data (which was also presented to the Editorial Office), and realized that errors has been made in the compilation of Fig. 2. The proposed revised version of Fig. 2, now showing the results from the 'field 1' view of the data, is shown on the next page. Note that these errors did not significantly affect either the results or the conclusions reported in this paper,.All the authors agree to the publication of this Corrigendum, and are grateful to the Editor of Molecular Medicine Reports for allowing them the opportunity to correct this error; furthermore, they apologize to the readership for any inconvenience caused. [Molecular Medicine Reports 25: 71, 2022; DOI: 10.3892/mmr.2022.12587].

3.
Sci Rep ; 14(1): 5344, 2024 03 04.
Artigo em Inglês | MEDLINE | ID: mdl-38438458

RESUMO

Chronic rotator cuff injuries (CRCIs) still present a great challenge for orthopaedics surgeons. Many new therapeutic strategies are developed to facilitate repair and improve the healing process. However, there is no reliable animal model for chronic rotator cuff injury research. To present a new valuable rat model for future chronic rotator cuff injuries (CRCIs) repair studies, and describe the changes of CRCIs on the perspectives of histology, behavior and MRI. Sixty male Wistar rats were enrolled and underwent surgery of the left shoulder joint for persistent subacromial impingement. They were randomly divided into experimental group (n = 30, a 3D printed PEEK implant shuttled into the lower surface of the acromion) and sham operation group (n = 30, insert the same implant, but remove it immediately). Analyses of histology, behavior, MRI and inflammatory pain-related genes expression profiles were performed to evaluate the changes of CRCIs. After 2-weeks running, the rats in the experimental group exhibited compensatory gait patterns to protect the injured forelimb from loading after 2-weeks running. After 8-weeks running, the rats in the experimental group showed obvious CRCIs pathological changes: (1) acromion bone hyperplasia and thickening of the cortical bone; (2) supraspinatus muscle tendon of the humeral head: the bursal-side tendon was torn and layered with disordered structure, forming obvious gaps; the humeral-side tendon is partially broken, and has a neatly arranged collagen. Partial fat infiltration is found. The coronal T2-weighted images showed that abnormal tendon-to-bone junctions of the supraspinatus tendon. The signal intensity and continuity were destroyed with contracted tendon. At the nighttime, compared with the sham operation group, the expression level of IL-1ß and COX-2 increased significantly (P = 0063, 0.0005) in the experimental group. The expression of COX-2 in experimental group is up-regulated about 1.5 times than that of daytime (P = 0.0011), but the expression of IL-1ß, TNF-a, and NGF are all down-regulated (P = 0.0146, 0.0232, 0.0161). This novel rat model of chronic rotator cuff injuries has the similar characteristics with that of human shoulders. And it supplies a cost-effective, reliable animal model for advanced tissue engineered strategies and future therapeutic strategies.


Assuntos
Lesões do Manguito Rotador , Humanos , Ratos , Animais , Masculino , Lesões do Manguito Rotador/diagnóstico por imagem , Ratos Wistar , Ciclo-Oxigenase 2 , Manguito Rotador/diagnóstico por imagem , Tendões , Interleucina-1beta
4.
Heliyon ; 10(5): e26618, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38455539

RESUMO

Background: Coinfection poses a persistent threat to global public health due to its severe effect on individual-level infection risk and disease outcome. Coinfection of SARS-CoV2 with one or more pathogens has been documented. Nevertheless, this virus co-infected with the Hantaan virus (HTNV) is rarely reported. Case summary: Here, we presented three cases of HTNV complicated with SARS-CoV2 infection. Not only the conditions including general clinical manifestations, immune and inflammation parameters fluctuation presented in the single infection of HTNV or SARS-CoV2 can be found, but also the unexpected manifestations have attracted our attention that presented as more symptoms of HTNV infection including exudative changes in both lungs and an amount of bilateral pleural effusion as well as bilateral kidney enlargement rather than typical viral pneumonia in SARS-CoV2 infection. Fortunately, the conditions of patients gradually return to normal which is beneficial from the antiviral treatment, hemodialysis, and various supportive therapies including anti-inflammation, liver and gastric mucosa protection. Conclusion: Unexpected manifestations of coinfection patients present herein may be associated with multiple factors including virus load, competition or antagonism among antigens, and the susceptibility of target cells to the various pathogens, even though the pathogenesis of HTNV and SARS-CoV2 remains to be elucidated. Given that these two viruses have posed a profound influence on the socioeconomic, healthcare system worldwide, and the threat of coinfection to public health, it is warranted for clinicians, public health authorities, and infectious disease researchers to have a high index of consideration for patients co-infected with HTNV and SARS-CoV2.

5.
Zhongguo Gu Shang ; 37(2): 153-8, 2024 Feb 25.
Artigo em Chinês | MEDLINE | ID: mdl-38425066

RESUMO

OBJECTIVE: To explore the potential value of three-dimensional fast spin echo(3D-SPACE) combined with multilayer spiral CT (MSCT) in the diagnosis of knee cruciate ligament injury, to provide a new direction for the optimization of subsequent clinical diagnosis. METHODS: A total of 120 patients with knee cruciate ligament injury were treated from April 2020 to April 2021, aged from 21 to 68 with an average of(41.52±4.13) years old. For all patients, separate MSCT scanner scans, 3D-SPACE sequence scans alone and 3D-SPACE sequence combined with MSCT scans were used. The injury and classification of the anterior and posterior cruciate ligament of the knee were compared, the length of the anterior-medial bundle and posterolateral bundle and its angle of the knee with the horizontal plane were observed, the diagnostic value of 3 diagnostic methods in knee cruciate ligament injury were determined. RESULTS: There was no significant difference between the 3D-SPACE sequence scan alone and the MSCT test alone on the total diagnostic rate and grading total diagnostic rate(P>0.05). The total diagnostic rate and grading total diagnostic rate of 3D-SPACE scan combined with MSCT were significantly higher than those of 3D-SPACE scan or MSCT alone(P<0.05). The 3D-SPACE sequence scan alone and the MSCT detection alone had no significant difference in the measurement values related to the anterior and posterior cruciate ligaments of the knee joint(P>0.05). 3D-SPACE sequence scanning combined with MSCT detection on the knee joint anterior and posterior cruciate ligament related measurements were significantly higher than the 3D-SPACE sequence scan or MSCT detection alone(P<0.05). The area under the ROC curve estimated by 3D-SPACE sequence scanning combined with MSCT was 0.960, which was significantly higher than that of 3D-SPACE sequence scanning and MSCT alone evaluating the area under the ROC curve line of 0.756 and 0.795. The combined 3D-SPACE sequence scanning and 3D-SPACE sequence scanning MSCT analysis and prediction models were statistically different(Z=2.236, P<0.05), and MSCT alone and 3D-SPACE sequence scanning combined with MSCT analysis and prediction models were statistically different(Z=2.653, P<0.05). CONCLUSION: The application of 3D-SPACE sequence combined with MSCT scanning for knee cruciate ligament injury can improve the diagnosis rate of patients with knee cruciate ligament injury.It can be used as a diagnostic tool for patients with knee cruciate ligament injury and is worthy of clinical application.


Assuntos
Lesões do Ligamento Cruzado Anterior , Traumatismos do Joelho , Ligamento Cruzado Posterior , Lesões dos Tecidos Moles , Humanos , Adulto , Pessoa de Meia-Idade , Imageamento por Ressonância Magnética/métodos , Artroscopia , Traumatismos do Joelho/diagnóstico por imagem , Articulação do Joelho/diagnóstico por imagem , Ligamento Cruzado Posterior/lesões , Tomografia Computadorizada Espiral , Lesões do Ligamento Cruzado Anterior/diagnóstico por imagem
6.
Nat Commun ; 15(1): 1079, 2024 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-38316752

RESUMO

The tendency of species to retain ancestral ecological distributions (phylogenetic niche conservatism) is thought to influence which species from a species pool can persist in a particular environment. Thus, investigating the relationships between measures of phylogenetic structure and environmental variables at a global scale can help understand the variation in species richness and phylogenetic structure in biological assemblages across the world. Here, we analyze a comprehensive data set including 341,846 species in 391 angiosperm floras worldwide to explore the relationships between measures of phylogenetic structure and environmental variables for angiosperms in regional floras across the world and for each of individual continental (biogeographic) regions. We find that the global phylogenetic structure of angiosperms shows clear and meaningful relationships with environmental factors. Current climatic variables have the highest predictive power, especially on phylogenetic metrics reflecting recent evolutionary relationships that are also related to current environmental heterogeneity, presumably because this favors plant speciation in various ways. We also find evidence that past climatic conditions, and particularly refugial conditions, play an important role in determining the phylogenetic structure of regional floras. The relationships between environmental conditions and phylogenetic metrics differ between continents, reflecting the different evolutionary histories of their floras.


Assuntos
Magnoliopsida , Filogenia , Magnoliopsida/genética , Evolução Biológica , Plantas , Ecossistema
7.
Adv Mater ; 36(15): e2310216, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38237136

RESUMO

The sprayable hydrogel coatings that can establish robust adhesion onto diverse materials and devices hold enormous potential; however, a significant challenge persists due to monomer hydration, which impedes even coverage during spraying and induces inadequate adhesion post-gelation. Herein, a polycation-reinforced (PCR) surface bridging strategy is presented to achieve tough and sprayable hydrogel coatings onto diverse materials. The polycations offer superior wettability and instant electrostatic interactions with plasma-treated substrates, facilitating an effective spraying application. This PCR-based hydrogel coatings demonstrate tough adhesion performance to inert PTFE and silicone, including remarkable shear strength (161 ± 49 kPa for PTFE), interfacial toughness (198 ± 27 J m-2 for PTFE), and notable tolerance to cyclic tension (10 000 cycles, 200% strain, silicone). Meanwhile, this method can be applied to various hydrogel formulations, offering diverse functionalities, including underwater adhesion, lubrication, and drug delivery. Furthermore, the PCR concept enables the conformal construction of durable hydrogel coatings onto sophisticated medical devices like cardiovascular stents. Given its simplicity and adaptability, this approach paves an avenue for incorporating hydrogels onto solid surfaces and potentially promotes untapped applications.


Assuntos
Hidrogéis , Polieletrólitos , Silicones , Politetrafluoretileno , Reação em Cadeia da Polimerase
8.
Viruses ; 16(1)2024 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-38275973

RESUMO

(1) Background: Avian influenza has attracted widespread attention because of its severe effect on the poultry industry and potential threat to human health. The H9N2 subtype of avian influenza viruses was the most prevalent in chickens, and there are several commercial vaccines available for the prevention of the H9N2 subtype of avian influenza viruses. However, due to the prompt antigenic drift and antigenic shift of influenza viruses, outbreaks of H9N2 viruses still continuously occur, so surveillance and vaccine updates for H9N2 subtype avian influenza viruses are particularly important. (2) Methods: In this study, we constructed a stable Chinese hamster ovary cell line (CHO) to express the H9 hemagglutinin (HA) protein of the major prevalent H9N2 strain A/chicken/Daye/DY0602/2017 with genetic engineering technology, and then a subunit H9 avian influenza vaccine was prepared using the purified HA protein with a water-in-oil adjuvant. (3) Results: The results showed that the HI antibodies significantly increased after vaccination with the H9 subunit vaccine in specific-pathogen-free (SPF) chickens with a dose-dependent potency of the immunized HA protein, and the 50 µg or more per dose HA protein could provide complete protection against the H9N2 virus challenge. (4) Conclusions: These results indicate that the CHO expression system could be a platform used to develop the subunit vaccine against H9 influenza viruses in chickens.


Assuntos
Vírus da Influenza A Subtipo H9N2 , Vacinas contra Influenza , Influenza Aviária , Animais , Humanos , Cricetinae , Vírus da Influenza A Subtipo H9N2/genética , Galinhas , Hemaglutininas , Cricetulus , Células CHO , Anticorpos Antivirais , Vacinas de Subunidades , Glicoproteínas de Hemaglutininação de Vírus da Influenza/genética
9.
Front Biosci (Landmark Ed) ; 29(1): 19, 2024 01 17.
Artigo em Inglês | MEDLINE | ID: mdl-38287820

RESUMO

BACKGROUND: Cutaneous squamous cell carcinoma (cSCC) is the second most common malignancy of the skin, and its incidence is increasing annually. Once cSCC becomes metastatic, its associated mortality rate is much higher than that of cSCC in situ. However, the current treatments for progressive cSCC have several limitations. The aim of this study was to suggest a potential compound for future research that may benefit patients with cSCC. METHODS: In this study, we screened the following differentially expressed genes from the Gene Expression Omnibus database: GSE42677, GSE45164, GSE66359, and GSE98767. Using strategies such as protein-protein interaction network analysis and the CYTOSCAPE plugin MCODE, key modules were identified and then verified by Western blotting. Subsequently, related signalling pathways were constituted in the SIGNOR database. Finally, molecular docking analyses and cell viability assay were used to identify a potential candidate drug and verify its growth inhibition ability to A431 cell line. RESULTS: Fifty-one common differentially expressed genes were screened and two key modules were identified. Among them, three core genes were extracted, constituting two signalling pathways, both of which belong to the module associated with mitotic spindles and cell division. A pathway involving CDK1, the TPX2-KIF11 complex, and spindle organization was validated in a series of analyses, including analyses for overall survival, genetic alteration, and molecular structure. Molecular docking analyses identified the pyridine 2-carbaldehyde thiosemicarbazone (NSC689534), which interacts with TPX2 and KIF11, as a potential candidate for the treatment of cSCC. CONCLUSIONS: NSC689534 might be a candidate drug for cSCC targeting TPX2 and KIF11, which are hub genes in cSCC.


Assuntos
Carcinoma de Células Escamosas , Neoplasias Cutâneas , Tiossemicarbazonas , Humanos , Carcinoma de Células Escamosas/tratamento farmacológico , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/patologia , Neoplasias Cutâneas/tratamento farmacológico , Neoplasias Cutâneas/genética , Simulação de Acoplamento Molecular , Transdução de Sinais/genética , Regulação Neoplásica da Expressão Gênica
10.
Biochem Genet ; 62(1): 452-467, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37380850

RESUMO

Rotator cuff tear (RCT) is a common shoulder disorder related to pain and dysfunction. However, the pathological mechanism of RCT remains unclear. Thus, this study aims to investigate the molecular events in RCT synovium and identify possible target genes and pathways as determined by RNA sequencing (RNA-Seq). The synovial tissue was biopsied from 3 patients with RCT (RCT group) and 3 patients with shoulder instability (Control group) during arthroscopic surgery. Then, differentially expressed (DE) mRNAs, long non-coding RNAs (lncRNAs) and micro RNAs (miRNAs) were comprehensively profiled by RNA-Seq. Gene ontology (GO) enrichment, Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway, and competing endogenous RNA (ceRNA) network analysis were performed to identify the potential functions of these DE genes. 447 mRNAs, 103 lncRNAs and 15 miRNAs were identified differentially expressed. The DE mRNAs were highlighted in inflammatory pathway including up-regulated T cell costimulation, positive regulation of T cell activation, and T cell receptor signaling. Down-regulated fatty acid degradation pathway and 5'-AMP-activated protein kinase (AMPK) signaling in RCT group are also enriched. Validation assay showed that the expression of pro-inflammatory molecules including IL21R, CCR5, TNFSF11, and MMP11 was significantly increased in RCT group compared with Control group. CeRNA analysis further revealed lncRNA-miRNA-mRNA regulatory networks involving IL21R and TNFSF11 in RCT. Activated synovial inflammation is the remarkable event of RCT. Importantly, increased T cell activation and disordered fatty acid metabolism signaling might play a significant role. ceRNA networks involving IL21R and TNFSF11 identified could potentially control the progression of RCT. In conclusion, our findings could provide new evidence for the molecular mechanisms of RCT and might identify new therapeutic targets.


Assuntos
MicroRNAs , RNA Longo não Codificante , Lesões do Manguito Rotador , Humanos , Lesões do Manguito Rotador/genética , Lesões do Manguito Rotador/cirurgia , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Redes Reguladoras de Genes , MicroRNAs/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Análise de Sequência de RNA , Receptores de Interleucina-21/genética , Expressão Gênica , Ácidos Graxos
11.
Asian J Surg ; 47(2): 1055-1056, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38042658
13.
Int J Biol Macromol ; 258(Pt 1): 128836, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38104683

RESUMO

The strategy of emulsion coating was used for grape preservation. Camellia oil (CO) was incorporated with KGM/curdlan (KC) to fabricate KC-CO emulsion systems. KC-CO emulsions were analyzed by droplet size distribution and confocal laser scanning microscopy (CLSM), and KC-CO films were investigated by scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), mechanical properties, dissolution, gas permeability, water contact angle (WCA). KC-CO coating was used for preservation of 'Kyoho' grapes. The results indicated that the addition of CO had a positive effect on KC system. CO could form a uniform emulsion with KC, and the droplets were evenly dispersed in the KC matrix. KC-CO films displayed a continuous microstructure, and elongation at break (EAB) was improved, while tensile strength decreased. The dissolution, water vapor permeability (WVP), and WCA were significantly enhanced, while the permeability of oxygen and carbon dioxide exhibited no advantage compared with KC film. KC-CO-10 possessed optimal properties and was selected as an emulsion coating for preservation. The results suggested that KC-CO-10 significantly maintained the appearance, total solid and acid content of 'Kyoho' grapes, and delayed the weight loss and firmness decrease. This study contributed to the understanding of polysaccharide-lipid emulsion system and the applications.


Assuntos
Camellia , Vitis , beta-Glucanas , Emulsões , Mananas/química , Permeabilidade , Óleos de Plantas
14.
Photochem Photobiol ; 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-38041414

RESUMO

We have employed the highly accurate multistate complete active space second-order perturbation theory (MS-CASPT2) method to investigate the photoinduced excited state relaxation properties of one unnatural base, namely Z. Upon excitation to the S2 state of Z, the internal conversion to the S1 state would be dominant. From the S1 state, two intersystem crossing paths leading to the T2 and T1 states and one internal conversion path to the S0 state are possible. However, considering the large barrier to access the S1 /S0 conical intersection and the strong spin-orbit coupling between S1 and T2 states (>40 cm-1 ), the intersystem crossing to the triplet manifolds is predicted to be more preferred. Arriving at the T2 state, the internal conversion to the T1 state and the intersystem crossing back to the S1 state are both possible considering the S1 /T2 /T1 three-state intersection near the T2 minimum. Upon arrival at the T1 state, the deactivation to S0 can be efficient after overcoming a small barrier to access T1 /S0 crossing point, where the spin-orbit coupling (SOC) is as large as 39.7 cm-1 . Our present work not only provides in-depth insights into the photoinduced process of unnatural base Z, but can also help the future design of novel unnatural bases with better photostability.

15.
Sci Rep ; 13(1): 21787, 2023 12 08.
Artigo em Inglês | MEDLINE | ID: mdl-38066109

RESUMO

Traumatic or degenerative joint pain is abundant in the population. Symptom relief by intra- and periarticular glucocorticoid administration is frequently used, however may have potentially devastating effects, changing the normal healing process of the joint. Mesenchymal stem cells (MSCs) are important for wound-healing processes due to their multipotency in regenerating osteoblasts, chondrocytes and adipocytes but also have immunomodulatory properties. The aim of this study was to investigate the impact of triamcinolone acetonide (TA) a common glucocorticoid administrated intra- and periarticularly, on human bone marrow derived MSC viability, functionality, multi-lineage differentiation and transcriptomic output. We found that TA treatment induced apoptosis and promoted adipogenesis while impairing chondrogenesis of MSCs. RNA sequencing indicated that TA modulated the inflammatory response of MSCs, which may have an impact on the immunologic environment where the inflammatory phase is a physiological part of the natural healing process. These data indicate that triamcinolone acetonide should be used with consideration bearing the patient's outcome in mind, with the intention to optimize joint recovery and homeostasis.


Assuntos
Células-Tronco Mesenquimais , Triancinolona Acetonida , Humanos , Triancinolona Acetonida/farmacologia , Glucocorticoides/farmacologia , Diferenciação Celular , Adipogenia/genética , Células da Medula Óssea
16.
Plant Divers ; 45(5): 491-500, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37936816

RESUMO

Beta diversity (ß-diversity) is the scalar between local (α) and regional (γ) diversity. Understanding geographic patterns of ß-diversity is central to ecology, biogeography, and conservation biology. A full understanding of the origin and maintenance of geographic patterns of ß-diversity requires exploring both taxonomic and phylogenetic ß-diversity, as well as their respective turnover and nestedness components, and exploring phylogenetic ß-diversity at different evolutionary depths. In this study, we explore and map geographic patterns of ß-diversity for angiosperm genera in regional floras across the world. We examine both taxonomic and phylogenetic ß-diversity and their constituent components, and both tip-weighted and basal-weighted phylogenetic ß-diversity, and relate them to latitude. On the one hand, our study found that the global distribution of ß-diversity is highly heterogeneous. This is the case for both taxonomic and phylogenetic ß-diversity, and for both tip-weighted and basal-weighted phylogenetic ß-diversity. On the other hand, our study found that there are highly consistent geographic patterns among different metrics of ß-diversity. In most cases, metrics of ß-diversity are negatively associated with latitude, particularly in the Northern Hemisphere. Different metrics of taxonomic ß-diversity are strongly and positively correlated with their counterparts of phylogenetic ß-diversity.

17.
Plant Divers ; 45(5): 535-543, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37936820

RESUMO

In eastern Asian subtropical forests, leaf habit shifts from evergreen to deciduous broad-leaved woody plants toward higher latitudes. This shift has been largely explained by the greater capacity of deciduous broad-leaved plants to respond to harsh climatic conditions (e.g., greater seasonality). The advantages of deciduous leaf habit over evergreen leaf habit in more seasonal climates have led us to hypothesize that leaf habits would shift in response to climate changes more conspicuously in forest canopy trees than in forest understory shrubs. Furthermore, we hypothesize that in the forests of the subtropics, plants at higher latitudes, regardless of growth form, would better tolerate seasonal harsh climates, and hence show less differentiation in leaf habit shift, compared to those at lower latitudes. To test these two hypotheses, we modelled the proportion of deciduous broad-leaved species and the incidence of deciduous and evergreen broad-leaved species in woody angiosperm species compositions of ten large-sized forest plots distributed in the Chinese subtropics. We found that the rate of leaf habit shift along a latitudinal gradient was higher in forest trees than in forest shrubs. We also found that the differentiation in leaf habit shift between trees and shrubs is greater at lower latitudes (i.e., warmer climates) than at higher latitudes (i.e., colder climates). These findings indicate that specialized forest plants are differentially affected by climate in distinct forest strata in a manner dependent on latitudinal distribution. These differences in forest plant response to changes in climate suggest that global climate warming will alter growth forms and geographical distributions and ranges of forests.

18.
Glob Ment Health (Camb) ; 10: e76, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38035148

RESUMO

The aims of this study were to examine the spillover effects of violent attacks, coronavirus disease-2019 (COVID-19) exposure, and their interactions on health professionals' mental health, and the role of organizational support in their relationships in China. A two-phase survey data (n = 10,901) before and after the first outbreak of COVID-19 was integrated with regional macro data on the number of lawsuit cases of violent attacks and COVID-19 cases. Three studies were designed to isolate the general spillover impact of violent attacks on the mental health of health professionals, how COVID-19 affects the mental health of health professionals, and whether organizational support moderates the relationship between violent attacks and mental health through econometric regressions. Violent attacks and COVID-19 are negatively associated with the mental health of health professionals, and the outbreak of COVID-19 adversely deteriorates the spillover effects of violent attacks. Physicians, not nurses, are the most affected group. Better perceived support from hospitals can significantly mitigate the adverse effects of COVID-19, violent attacks, and their interactions on the mental health of health professionals. COVID-19 deteriorates the adverse effects of violent attacks on the mental health of health professionals, while better organizational support is helpful to mitigate these effects.

19.
Sci Adv ; 9(46): eadj1022, 2023 11 17.
Artigo em Inglês | MEDLINE | ID: mdl-37967173

RESUMO

Although originating from a common Gondwanan flora, the diversity and composition of the floras of Africa and South America have greatly diverged since continental breakup of Africa from South America now having much higher plant species richness. However, the phylogenetic diversity of the floras and what this tells us about their evolution remained unexplored. We show that for a given species richness and considering land surface area, topography, and present-day climate, angiosperm phylogenetic diversity in South America is higher than in Africa. This relationship holds regardless of whether all climatically matched areas or only matched areas in tropical climates are considered. Phylogenetic diversity is high relative to species richness in refugial areas in Africa and in northwestern South America, once the gateway for immigration from the north. While species richness is strongly influenced by massive plant radiations in South America, we detect a pervasive influence of historical processes on the phylogenetic diversity of both the South American and African floras.


Assuntos
Magnoliopsida , Filogenia , Magnoliopsida/genética , América do Sul , África , Clima Tropical , Biodiversidade
20.
ArXiv ; 2023 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-37904742

RESUMO

Recent studies at individual cell resolution have revealed phenotypic heterogeneity in nominally clonal tumor cell populations. The heterogeneity affects cell growth behaviors, which can result in departure from the idealized uniform exponential growth of the cell population. Here we measured the stochastic time courses of growth of an ensemble of populations of HL60 leukemia cells in cultures, starting with distinct initial cell numbers to capture a departure from the uniform exponential growth model for the initial growth ("take-off"). Despite being derived from the same cell clone, we observed significant variations in the early growth patterns of individual cultures with statistically significant differences in growth dynamics, which could be explained by the presence of inter-converting subpopulations with different growth rates, and which could last for many generations. Based on the hypothesis of existence of multiple subpopulations, we developed a branching process model that was consistent with the experimental observations.

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