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1.
J Synchrotron Radiat ; 31(Pt 1): 55-64, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-37930257

RESUMO

X-ray photon correlation spectroscopy (XPCS) holds strong promise for observing atomic-scale dynamics in materials, both at equilibrium and during non-equilibrium transitions. Here an in situ XPCS study of the relaxor ferroelectric PbMg1/3Nb2/3O3 (PMN) is reported. A weak applied AC electric field generates strong response in the speckle of the diffuse scattering from the polar nanodomains, which is captured using the two-time correlation function. Correlated motions of the Bragg peak are also observed, which indicate dynamic tilting of the illuminated volume. This tilting quantitatively accounts for the observed two-time speckle correlations. The magnitude of the tilting would not be expected solely from the modest applied field, since PMN is an electrostrictive material with no linear strain response to the field. A model is developed based on non-uniform static charging of the illuminated surface spot by the incident micrometre-scale X-ray beam and the electrostrictive material response to the combination of static and dynamic fields. The model qualitatively explains the direction and magnitude of the observed tilting, and predicts that X-ray-induced piezoresponse could be an important factor in correctly interpreting results from XPCS and nanodiffraction studies of other insulating materials under applied AC field or varying X-ray illumination.

2.
Planta ; 259(5): 115, 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38589536

RESUMO

MAIN CONCLUSION: A member of the rice GT61 clade B is capable of transferring both 2-O-xylosyl and 2-O-arabinosyl residues onto xylan and another member specifically catalyses addition of 2-O-xylosyl residue onto xylan. Grass xylan is substituted predominantly with 3-O-arabinofuranose (Araf) as well as with some minor side chains, such as 2-O-Araf and 2-O-(methyl)glucuronic acid [(Me)GlcA]. 3-O-Arabinosylation of grass xylan has been shown to be catalysed by grass-expanded clade A members of the glycosyltransferase family 61. However, glycosyltransferases mediating 2-O-arabinosylation of grass xylan remain elusive. Here, we performed biochemical studies of two rice GT61 clade B members and found that one of them was capable of transferring both xylosyl (Xyl) and Araf residues from UDP-Xyl and UDP-Araf, respectively, onto xylooligomer acceptors, whereas the other specifically catalysed Xyl transfer onto xylooligomers, indicating that the former is a xylan xylosyl/arabinosyl transferase (named OsXXAT1 herein) and the latter is a xylan xylosyltransferase (named OsXYXT2). Structural analysis of the OsXXAT1- and OsXYXT2-catalysed reaction products revealed that the Xyl and Araf residues were transferred onto O-2 positions of xylooligomers. Furthermore, we demonstrated that OsXXAT1 and OsXYXT2 were able to substitute acetylated xylooligomers, but only OsXXAT1 could xylosylate GlcA-substituted xylooligomers. OsXXAT1 and OsXYXT2 were predicted to adopt a GT-B fold structure and molecular docking revealed candidate amino acid residues at the predicted active site involved in binding of the nucleotide sugar donor and the xylohexaose acceptor substrates. Together, our results establish that OsXXAT1 is a xylan 2-O-xylosyl/2-O-arabinosyl transferase and OsXYXT2 is a xylan 2-O-xylosyltransferase, which expands our knowledge of roles of the GT61 family in grass xylan synthesis.


Assuntos
Arabidopsis , Oryza , Glicosiltransferases/análise , Oryza/metabolismo , Xilanos/metabolismo , Arabidopsis/metabolismo , Simulação de Acoplamento Molecular , UDP Xilose-Proteína Xilosiltransferase , Poaceae/metabolismo , Parede Celular/metabolismo
3.
Plant Biotechnol J ; 22(6): 1435-1452, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38194521

RESUMO

Wolfberry is a plant with medicinal and food values. However, its bioactive ingredients and the corresponding genetic bases have not been determined. Here, we de novo generated a chromosome-level genome assembly for wolfberry, yielding a genome sequence of ~1.77 Gb with contig N50 of 50.55 Mb and 39 224 predicted gene models. A variation map, using 307 re-sequenced accessions, was called based on this genome assembly. Furthermore, the fruit metabolome of these accessions was profiled using 563 annotated metabolites, which separated Lycium barbarum L. and non-L. barbarum L. The flavonoids, coumarins, alkaloids and nicotinic acid contents were higher in the former than in the latter. A metabolite-based genome-wide association study mapped 156 164 significant single nucleotide polymorphisms corresponding to 340 metabolites. This included 19 219 unique lead single nucleotide polymorphisms in 1517 significant association loci, of which three metabolites, flavonoids, betaine and spermidine, were highlighted. Two candidate genes, LbUGT (evm.TU.chr07.2692) and LbCHS (evm.TU.chr07.2738), with non-synonymous mutations, were associated with the flavonoids content. LbCHS is a structural gene that interacts with a nearby MYB transcription factor (evm.TU.chr07.2726) both in L. barbarum and L. ruthenicum. Thus, these three genes might be involved in the biosynthesis/metabolism of flavonoids. LbSSADH (evm.TU.chr09.627) was identified as possibly participating in betaine biosynthesis/metabolism. Four lycibarbarspermidines (E-G and O) were identified, and only the lycibarbarspermidines O content was higher in L. barbarum varieties than in non-L. barbarum varieties. The evm.TU.chr07.2680 gene associated with lycibarbarspermidines O was annotated as an acetyl-CoA-benzylalcohol acetyltransferase, suggesting that it is a candidate gene for spermidine biosynthesis. These results provide novel insights into the specific metabolite profile of non-L. barbarum L. and the genetic bases of flavonoids, betaine and spermidine biosynthesis/metabolism.


Assuntos
Betaína , Flavonoides , Estudo de Associação Genômica Ampla , Lycium , Polimorfismo de Nucleotídeo Único , Espermidina , Flavonoides/metabolismo , Lycium/genética , Lycium/metabolismo , Espermidina/metabolismo , Betaína/metabolismo , Polimorfismo de Nucleotídeo Único/genética , Genoma de Planta/genética , Frutas/genética , Frutas/metabolismo
4.
Phys Rev Lett ; 132(19): 191901, 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38804936

RESUMO

We present the first lattice QCD calculation of the universal axial γW-box contribution □_{γW}^{VA} to both superallowed nuclear and neutron beta decays. This contribution emerges as a significant component within the theoretical uncertainties surrounding the extraction of |V_{ud}| from superallowed decays. Our calculation is conducted using two domain wall fermion ensembles at the physical pion mass. To construct the nucleon four-point correlation functions, we employ the random sparsening field technique. Furthermore, we incorporate long-distance contributions to the hadronic function using the infinite-volume reconstruction method. Upon performing the continuum extrapolation, we arrive at □_{γW}^{VA}=3.65(7)_{lat}(1)_{PT}×10^{-3}. Consequently, this yields a slightly higher value of |V_{ud}|=0.973 86(11)_{exp}(9)_{RC}(27)_{NS}, reducing the previous 2.1σ tension with the CKM unitarity to 1.8σ. Additionally, we calculate the vector γW-box contribution to the axial charge g_{A}, denoted as □_{γW}^{VV}, and explore its potential implications.

5.
Chemistry ; : e202401591, 2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38844428

RESUMO

The Ni-catalyzed enantioselective addition reaction of aryl halides to aldehydes was studied with cyanobis(oxazoline) as chiral ligands and Mn as reductant. Aryl and heteroaryl bromides reacted with phenyl aldehyde at room temperature to produce dibenzyl alcohols in 16-99% yields with 53-92% ees. Moreover, the coupling of phenyl chloride with a variety of aryl, heteroaryl and alkyl aldehydes was demonstrated in the presence of cyanobis(oxazoline)/Ni(II) at 60 oC in generally high yields with moderate enantioselectivities.

6.
J Org Chem ; 89(6): 4085-4097, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38394366

RESUMO

A palladium-catalyzed annulative π-extension reaction of bay-iodinated triphenylenes with aryl iodides/o-chloroaromatic carboxylic acids was developed. This approach enabled the synthesis of diverse polycyclic aromatic compounds, including dibenzo[fg,op]tetracenes, azadibenzo[fg,op]tetracenes, and tribenzo[a,g,m]coronenes. Initial studies indicate that the resulting product, 2,3,8,9,14,15-hexakis(decyloxy)tribenzo[a,g,m]coronene, exhibits good liquid-crystalline properties.

7.
BJOG ; 131(7): 952-960, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38168494

RESUMO

OBJECTIVE: To assess pelvic floor muscle (PFM) strength and influencing factors among healthy women at different life stages. DESIGN: Multicentre cross-sectional study. SETTING: Fourteen hospitals in China. POPULATION: A total of 5040 healthy women allocated to the following groups (with 1680 women per group): premenopausal nulliparous, premenopausal parous and postmenopausal. METHODS: The PFM strength was evaluated by vaginal manometry. Multivariate logistic regression was used to determine the influencing factors for low PFM strength. MAIN OUTCOME MEASURES: Maximum voluntary contraction pressure (MVCP). RESULTS: The median MVCP values were 36, 35 and 35 cmH2O in premenopausal nulliparous (aged 19-51 years), premenopausal parous (aged 22-61 years), and postmenopausal (aged 40-86 years) women, respectively. In the premenopausal nulliparous group, physical work (odds ratio, OR 2.05) was the risk factor for low PFM strength, which may be related to the chronic increased abdominal pressure caused by physical work. In the premenopausal parous group, the number of vaginal deliveries (OR 1.28) and diabetes (OR 2.70) were risk factors for low PFM strength, whereas sexual intercourse (<2 times per week vs. none, OR 0.55; ≥2 times per week vs. none, OR 0.56) and PFM exercise (OR 0.50) may have protective effects. In the postmenopausal group, the number of vaginal deliveries (OR 1.32) and family history of pelvic organ prolapse (POP) (OR 1.83) were risk factors for low PFM strength. CONCLUSIONS: Physical work, vaginal delivery, diabetes and a family history of POP are all risk factors for low PFM strength, whereas PFM exercises and sexual life can have a protective effect. The importance of these factors varies at different stages of a woman's life.


Assuntos
Manometria , Força Muscular , Diafragma da Pelve , Pós-Menopausa , Pré-Menopausa , Vagina , Humanos , Feminino , Pessoa de Meia-Idade , Estudos Transversais , Diafragma da Pelve/fisiologia , Adulto , Manometria/métodos , Força Muscular/fisiologia , Idoso , Pós-Menopausa/fisiologia , Pré-Menopausa/fisiologia , Vagina/fisiologia , Fatores de Risco , Idoso de 80 Anos ou mais , Adulto Jovem , Paridade , China/epidemiologia , Contração Muscular/fisiologia , Gravidez
8.
Sleep Breath ; 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38689200

RESUMO

OBJECTIVE: This study aims to provide physicians with insights into the clinical manifestations and outcomes of children and young adolescents experiencing sleep terrors following SARS-CoV-2 infection. METHODS: We enrolled patients who developed new onset sleep terrors after SARS-CoV-2infection fromDecember2022to April 2023 in the Xijing hospital, Xi'an, China. RESULTS: We enrolled six patients who experienced sleep terrors following SARS-CoV-2 infection. Out of these patients, five were children and only one was an adolescent, with a mean age of 9 years. Neuroimaging results were negative for all cases. Sleep terrors occurred during both the active course of COVID-19 illness and the recovery period in all patients. Symptoms included crying or screaming in terror, hyperactivity, inappropriate behavior and periods of mental confusion during sleep. These episodes typically occurred 40 min to 1 h after falling asleep. EEG monitoring confirmed two patients' episodes occurred during non-rapid eye movement (NREM) stage 3 sleep. The duration of sleep terrors ranged from 3mines to30 mines, with each patient experiencing 3-4 to 30-40 instances. Initially, the frequency of episodes was highest at 3-4 times per night, gradually decreasing to once a night, then once a week, until complete disappearance. No medical intervention was required. Clinical follow-up ranged from 6 to 12 months, with spontaneous remission occurring within 1 week to 2 months for different patients. CONCLUSION: SARS-CoV-2 infection may precipitate acute sleep terrors in children and adolescents. The course of these sleep terrors is generally benign, with all patients achieving spontaneous complete remission over time.

9.
Plant Dis ; 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38587792

RESUMO

Euphorbia lathyris L. is a biennial herb in the Euphorbiaceae that has been used as a medicinal plant. It is distributed or cultivated worldwide, and the seeds of E. lathyris are the main source of ingenol, which is the precursor of Picato, the first medicine approved by USFDA for the treatment of solar keratosis (Abramovits et al. 2013). However, the production of E. lathyris can be severely hampered by the occurrence of plant diseases. Between 2020-2022 (specifically in October-November of each year), anthracnose-like symptoms were observed on E. lathyris in fields (E 118°49'50″, N 32°3'33″) in Nanjing, Jiangsu Province, China. The incidence of E. lathyris with disease symptoms was between 25%-30% (n = 100). The lesions on the leaves were evident initially as dark brown spots, which expanded into larger necrotic spots, finally resulting in leaves withering and dropping off. In severe cases, stem wilting was also observed. To determine the causal agent, we collected diseased leaf samples (n = 20) from different E. lathyris plants in the field (~ 1800 m2). After cleaning, the junctions of the diseased and healthy parts were excised and sterilized in 75% ethanol for 20-25 seconds, and rinsed with sterile water. After that, they were transferred onto potato sucrose agar (PSA) plates and placed at 25℃ for 3-4 days, until fungal growth was evident. The fungus was purified by recovering single conidia and growing them on PSA (Hu et al. 2015). A consistent fungal colony, based on morphological characteristics, was recovered from 17 samples. The colony color was initially white, green in the middle, and gradually changed into gray green as the colony matured. Conidia were transparent and cylindrical (22-28 µm × 7-9 µm, n = 50). Five loci informative (ITS, TUB, ACT, GAPDH, and CHS-1) (Weir et al. 2012) for Colletotrichum spp. identification were sequenced from two isolates ELC-1 and ELC-2 obtained from different plant individuals. Compared with a reference isolate (Colletotrichum gloeosporioides ZH3), the GAPDH, CHS-1, and TUB2 sequences of ELC-1 and ELC-2 showed 95% (263 bp out of 275 bp), 98% (295 bp out of 299 bp), and 99% (711 bp out of 712 bp and 717 bp out of 719 bp) similarity, respectively. The ITS sequence identities were 100% (577 bp out of 577 bp) and 99% (594 bp out of 597 bp), while the ACT sequence identities were 100% (281 bp out of 281 bp) and 98% (279 bp out of 284 bp). All sequences have been deposited in Genbank database (OR865865-OR865866 and OR873625-OR873632). After performing phylogenetic analysis with Mega 11, the pathogen was confirmed as C. gloeosporioides. To fulfil Koch's postulates, we sprayed six-week-old healthy plants with a conidia suspension of C. gloeosporioides (106 spores/mL) or sterile water (serve as control). The inoculated plants were placed at 25℃, 100% relative humidity, and 12-h photoperiod (Zhang et al. 2021). Six plants were inoculated for each treatment, and the experiment was repeated three times. After 6-8 days, the plants inoculated with C. gloeosporioides showed similar symptoms to those observed on diseased plants in the field, while the control plants remained healthy and free of disease. The pathogens were then re-isolated and identified as C. gloeosporioides. To our knowledge, this is the first report of C. gloeosporioides causing anthracnose on E. lathyris. Anthracnose may cause significant yield losses in E. lathyris production, and our results will provide experimental and theoretical basis for the management of the disease.

10.
Int J Mol Sci ; 25(2)2024 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-38256166

RESUMO

Prostate cancer (PCa) has been known as the most prevalent cancer disease and the second leading cause of cancer mortality in men almost all over the globe. There is an urgent need for establishment of PCa models that can recapitulate the progress of genomic landscapes and molecular alterations during development and progression of this disease. Notably, several organoid models have been developed for assessing the complex interaction between PCa and its surrounding microenvironment. In recent years, PCa organoids have been emerged as powerful in vitro 3D model systems that recapitulate the molecular features (such as genomic/epigenomic changes and tumor microenvironment) of PCa metastatic tumors. In addition, application of organoid technology in mechanistic studies (i.e., for understanding cellular/subcellular and molecular alterations) and translational medicine has been recognized as a promising approach for facilitating the development of potential biomarkers and novel therapeutic strategies. In this review, we summarize the application of PCa organoids in the high-throughput screening and establishment of relevant xenografts for developing novel therapeutics for metastatic, castration resistant, and neuroendocrine PCa. These organoid-based studies are expected to expand our knowledge from basic research to clinical applications for PCa diseases. Furthermore, we also highlight the optimization of PCa cultures and establishment of promising 3D organoid models for in vitro and in vivo investigations, ultimately facilitating mechanistic studies and development of novel clinical diagnosis/prognosis and therapies for PCa.


Assuntos
Medicina de Precisão , Neoplasias da Próstata , Masculino , Humanos , Neoplasias da Próstata/genética , Próstata , Organoides , Epigenômica , Microambiente Tumoral
11.
Molecules ; 29(5)2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38474571

RESUMO

The Euodia genus comprises numerous untapped medicinal plants that warrant thorough evaluation for their potential as valuable natural sources of herbal medicine or food flavorings. In this study, untargeted metabolomics and in vitro functional methods were employed to analyze fruit extracts from 11 significant species of the Euodia genus. An investigation of the distribution of metabolites (quinolone and indole quinazoline alkaloids) in these species indicated that E. rutaecarpa (Euodia rutaecarpa) was the most widely distributed species, followed by E. compacta (Euodia compacta), E. glabrifolia (Euodia glabrifolia), E. austrosinensis (Euodia austrosinensis), and E. fargesii (Euodia fargesii). There have been reports on the close correlation between indole quinazoline alkaloids and their anti-tumor activity, especially in E. rutaecarpa fruits which exhibit effectiveness against various types of cancer, such as SGC-7901, Hela, A549, and other cancer cell lines. Additionally, the E. rutaecarpa plant contains indole quinazoline alkaloids, which possess remarkable antibacterial properties. Our results offer novel insights into the utilization of Euodia resources in the pharmaceutical industry.


Assuntos
Alcaloides , Evodia , Plantas Medicinais , Quinolonas , Rutaceae , Humanos , Extratos Vegetais , Alcaloides Indólicos , Células HeLa , Quinazolinas
12.
Angew Chem Int Ed Engl ; 63(13): e202317433, 2024 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-38086770

RESUMO

Transition metal-catalyzed annulations of four-membered rings via C-C activation are powerful tools to construct complex fused and bridged ring systems. Despite significant progress in (4+1), (4+2) and (4+4) annulations, the (4+3) annulation remains unexplored. Herein, we develop an asymmetric Rh-catalyzed intramolecular (4+3) annulation of α-arylalkene-tethered benzocyclobutenols for the synthesis of dihydrofuran-annulated dibenzocycloheptanols with two discontinuous chiral carbon centers via a C-C and C-H activation cascade. The reaction features excellent diastereo- and enantioselectivities and 100 % atom economy, and is applicable to late-stage modification of complex molecules.

13.
Small ; 19(34): e2300801, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37072877

RESUMO

Sub-10 nm nanoparticles are known to exhibit extraordinary size-dependent properties for wide applications. Many approaches have been developed for synthesizing sub-10 nm inorganic nanoparticles, but the fabrication of sub-10 nm polymeric nanoparticles is still challenging. Here, a scalable, spontaneous confined nanoemulsification strategy that produces uniform sub-10 nm nanodroplets for template synthesis of sub-10 nm polymeric nanoparticles is proposed. This strategy introduces a high-concentration interfacial reaction to create overpopulated surfactants that are insoluble at the droplet surface. These overpopulated surfactants act as barriers, resulting in highly accumulated surfactants inside the droplet via a confined reaction. These surfactants exhibit significantly changed packing geometry, solubility, and interfacial activity to enhance the molecular-level impact on interfacial instability for creating sub-10 nm nanoemulsions via self-burst nanoemulsification. Using the nanodroplets as templates, the fabrication of uniform sub-10 nm polymeric nanoparticles, as small as 3.5 nm, made from biocompatible polymers and capable of efficient drug encapsulation is demonstrated. This work opens up brand-new opportunities to easily create sub-10 nm nanoemulsions and advanced ultrasmall functional nanoparticles.

14.
Chemistry ; 29(56): e202301829, 2023 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-37452614

RESUMO

The straightforward synthesis of several Fluorinated Polycyclic Aromatic Hydrocarbons by the efficient, transition-metal-free, arene fluorine nucleophilic substitution reaction is described, and the full investigation of their liquid crystalline and optical properties reported. The key precursors for this study, i. e. 2,2'-dilithio-4,4',5,5'-tetraalkoxy-1,1'-biphenyl derivatives, were obtained in two steps from the highly selective Scholl oxidative homo-coupling of 3,4-dialkoxy-1-bromobenzene, followed by quantitative double-lithiation. In situ room temperature nucleophilic annulation with either perfluorobenzene or perfluoronaphthalene leads to 1,2,3,4-tetrafluoro-6,7,10,11-tetraalkxoytriphenylenes and 9,10,11,12,13,14-hexafluoro-2,3,6,7-tetraalkoxybenzo[f]tetraphenes, respectively, in good yields. Exploiting the same strategy, subsequent double annulations resulted in the formation of 9,18-difluoro-2,3,6,7,11,12,15,16-octa(alkoxy)tribenzo[f,k,m]tetraphenes and 9,10,19,20-tetrafluoro-2,3,6,7,12,13,16,17-octakis(hexyloxy)tetrabenzo[a,c,j,l]tetracenes, respectively. Despite the presence of only four alkoxy chains, the polar "Janus" mesogens display a columnar hexagonal mesophase over broad temperature ranges, with higher mesophase stability than the archetypical 2,3,6,7,10,11-hexa(alkoxy)triphenylenes and their hydrogenated counterparts. The improvement or induction of mesomorphism is attributed to efficient antiparallel face-to-face π-stacking driven by the establishment of non-covalent perfluoroarene-arene intermolecular interactions. The larger lipophilic discotic π-extended compounds also exhibit columnar mesomorphism, over similar temperature ranges and stability than their hydrogenated homologs. Finally, these fluorinated molecules form stringy gels in various solvents, and show interesting solvatochromic emission properties in solution as well as strong emission in thin films and gels.

15.
Langmuir ; 39(7): 2719-2728, 2023 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-36753560

RESUMO

Thermoelectric (TE) performance of the Janus ZrSSe monolayer under biaxial strain is systematically explored by the first-principles approach and Boltzmann transport theory. Our results show that the Janus ZrSSe monolayer has excellent chemical, dynamical, thermal, and mechanical stabilities, which provide a reliable platform for strain tuning. The electronic structure and TE transport parameters of the Janus ZrSSe monolayer can be obviously tuned by biaxial strain. Under 2% tensile strain, the optimal power factor PF of the n-type-doped Janus ZrSSe monolayer reaches 46.36 m W m-1 K-2 at 300 K. This value is higher than that of the most classical TE materials. Under 6% tensile strain, the maximum ZT values for the p-type- and n-type-doped Janus ZrSSe monolayers are 4.41 and 4.88, respectively, which are about 3.83 and 1.49 times the results of no strain, respectively. Such high TE performance can be attributed to high band degeneracy and short phonon relaxation time under strain, causing simultaneous increase of the Seebeck coefficient and suppression of the phonon thermal transport. Present work demonstrates that the Janus ZrSSe monolayer is a promising candidate as a strain-tunable TE material and stimulates further experimental synthesis.

16.
Soft Matter ; 19(24): 4526-4535, 2023 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-37306079

RESUMO

Collective cell migration plays a vital role in various physiological and pathological processes, such as embryonic development and tumor metastasis. Recent experiments have shown that different from isolated cells, the moving cell groups exhibit rich emerging motion modes in response to external geometrical constraints. By considering the interactions between neighboring cells and internal biomechanical processes of each cell (i.e., cell sociality and cell individuality), we develop an active vertex model to investigate the emerging modes of collective cell migration in microchannels. Single-cell polarization is propelled by continuous protrusion of its leading edge and retraction of the rear. We here introduce the contribution of continuous protrusions and retractions of lamellipodia, named the protrusion alignment mechanism, to the cell individuality. Using the present model, it is found that altering the width of channels can trigger the motion mode transitions of cell groups. When cells move in narrow channels, the protrusion alignment mechanism brings neighboring groups of coordinated cells into conflicts and in turn induces the caterpillar-like motion mode. As the channel width increases, local swirls spanning the channel in width first appear as long as the channel width is smaller than the intrinsic correlation length of cell groups. Then, only local swirls with a maximum diameter of the intrinsic correlation length are formed, when the channel is sufficiently wider. These rich dynamical modes of collective cells originate from the competition between cell individuality and sociality. In addition, the velocity of the cell sheet invading free spaces varies with the channel size-induced transitions of migration modes. Our predictions are in broad agreement with many experiments and may shed light on the spatiotemporal dynamics of active matter.


Assuntos
Movimento Celular , Movimento Celular/fisiologia , Movimento (Física)
17.
Avian Pathol ; 52(1): 51-61, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36200987

RESUMO

Eimeria tenella (E. tenella), an important intestinal parasite of chicken caeca, causes coccidiosis and brings large economic losses to the poultry industry annually. Gut microorganismal alterations directly affect the health of the body. To understand how E. tenella affects its host, we analysed the changes in caecal microbial diversity and the physiological and morphological changes during the peak of oocyst shedding. Infected and healthy chickens differed significantly in caecal pathology and blood indicators. At the genus level, the abundances of Faecalibacterium, Clostridium, Lachnoclostridium, Gemmiger, Flavonifractor, Pseudoflavonifractor and Oscillibacter were significantly decreased in the infected samples, whereas Escherichia, Nocardia and Chlamydia were significantly increased. Functional gene pathways related to replication, recombination and repair, and transcription were significantly decreased, and functional genes related to metabolism were highly significantly reduced in the infected samples. Furthermore, in the infected samples, E. tenella reduced the haemoglobin levels and red blood cell counts, greatly reduced the beneficial bacteria and increased the potentially pathogenic bacteria. This study provides a research basis for further understanding the pathogenic mechanisms of E. tenella and provides insight for potential new drug development.RESEARCH HIGHLIGHTS First simultaneous description of caecal microbiota and physiological indicators during E. tenella infection.Metagenomics used to explore functional properties of chicken caecal microbiota during E. tenella infection.Caecal microbial compositions and functional genes altered significantly after infection.Blood indicators and caecal morphology were significantly altered in the infected group.


Assuntos
Coccidiose , Eimeria tenella , Microbiota , Doenças das Aves Domésticas , Animais , Eimeria tenella/genética , Galinhas/microbiologia , Doenças das Aves Domésticas/microbiologia , Oocistos/fisiologia , Coccidiose/parasitologia , Coccidiose/veterinária
18.
Sleep Breath ; 27(1): 363-369, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-35460050

RESUMO

PURPOSE: The cause of benign prostatic hyperplasia (BPH) is controversial, local hypoxia and inflammation being the main two possibilities proposed. The aim of this study was to evaluate the relationship between obstructive sleep apnea (OSA) and BPH. METHODS: The study cohort comprised men from January 2016 to December 2020 in our Sleep Center. These patients were classified into four groups (no, mild, moderate, severe OSA) by apnea-hypopnea indexes (AHI). Logistic regression was used to identify independent risk factors for BPH, after which participants were stratified into younger (age ≤ 40 years) and older groups (age > 40 years) for further analysis. RESULTS: The study cohort comprised 467 patients including 135 younger subjects and 332 older subjects. The prevalence of BPH in the above listed AHI categories was 37.5%, 55.0%, 62.9%, and 52.3%, respectively (p = 0.075). Logistic regression analysis of all patients identified age as a risk factor for BPH (p < 0.001). Stratified analysis according to AHI category found a prevalence of BPH of 0.0%, 13.0%, 33.3%, and 43.9%, respectively, in younger group (p = 0.006), and 52.2%, 71.9%, 71.1%, and 56.3%, respectively, in older group (p = 0.038). Logistic regression analysis found age and AHI were independent risk factors for BPH in younger group (both p < 0.05), whereas only age was identified as a risk factor for BPH in older group (p < 0.001). CONCLUSIONS: Age is an independent risk factor for BPH in men with OSA. AHI is also an independent risk factor for BPH in younger men, suggesting that OSA may affect development of BPH in younger men.


Assuntos
Hiperplasia Prostática , Apneia Obstrutiva do Sono , Masculino , Humanos , Idoso , Adulto , Hiperplasia Prostática/complicações , Hiperplasia Prostática/diagnóstico , Hiperplasia Prostática/epidemiologia , Apneia Obstrutiva do Sono/diagnóstico , Apneia Obstrutiva do Sono/epidemiologia , Fatores de Risco , Prevalência , Modelos Logísticos
19.
Sleep Breath ; 27(4): 1465-1471, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-36474109

RESUMO

OBJECTIVE: We aimed to examine the influence of sleep disturbances on the risk of oligo/astheno/teratozoospermia (OAT) in men attending an infertility clinic. METHODS: We consecutively enrolled men attending an infertility clinic from July 2020 to June 2021. Semen parameters were obtained at initial presentation, and the Pittsburgh Sleep Quality Index, Epworth Sleepiness Scale score, and the STOP-BANG Questionnair were completed to assess sleep quality. Embryo outcomes were evaluated after infertility treatment. RESULTS: Of 466 men enrolled, 119 had OAT (OAT group) and 347 had normozoospermia (NS group). There were no differences between the two groups regarding Epworth Sleepiness Scale and STOP-BANG Questionnaire scores. The prevalence of poor sleep quality (Pittsburgh Sleep Quality Index score ≥ 5) in the OAT group was significantly higher than that in the NS group (42% vs. 29%, p = 0.009). A higher rate of poor subjective sleep quality was observed in the OAT group compared with the NS group (p = 0.005) and Pearson's correlations revealed a negative relationship between subjective sleep quality and semen quality. Logistic regression found that subjective sleep quality was independently associated with an increased risk of OAT (adjusted odds ratio = 0.610, p = 0.007). CONCLUSIONS: Men with OAT attending an infertility clinic exhibited poor subjective sleep quality. Improving sleep disturbances may be a target intervention to reduce the risk of OAT. This possibility warrants further investigation.


Assuntos
Distúrbios do Início e da Manutenção do Sono , Transtornos do Sono-Vigília , Teratozoospermia , Masculino , Humanos , Autorrelato , Estudos Longitudinais , Qualidade do Sono , Análise do Sêmen , Clínicas de Fertilização , Sonolência , Transtornos do Sono-Vigília/diagnóstico , Transtornos do Sono-Vigília/epidemiologia
20.
Int J Clin Pract ; 2023: 9310588, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36694611

RESUMO

Background: Older age is a risk factor for obstructive sleep apnea (OSA), which is associated with the development of nonalcoholic fatty liver disease (NAFLD). We aimed to investigate the correlation between OSA and liver injury among older patients. Study Design. This is a cross-sectional study. Methods: Consecutive older (≥60 years) snoring patients were included. Subjects were divided into no OSA, mild OSA, moderate OSA, and severe OSA groups according to the apnea-hypopnea index (AHI) and were also separated into liver injury and nonliver injury groups based on liver function. Logistic regression analysis was applied to analyze the independent risk factors for liver injury. Results: We studied 227 patients (155 male, 72 female). The prevalence of liver injury exhibited an increasing trend among groups with mild-to-severe OSA. In addition, body mass index, AHI, and TG showed significant differences between the liver injury and nonliver injury groups. Logistic regression analysis revealed that AHI and TG were the major contributing factors for liver injury in older patients (adjusted odds ratio [OR] = 1.055, p=0.013, and OR = 1.485, p=0.039, respectively). Conclusions: Older patients with OSA have an increased risk of liver injury and NAFLD, and sleep apnea and high TG are important factors in contributing to the development of liver injury.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Apneia Obstrutiva do Sono , Humanos , Masculino , Feminino , Idoso , Hepatopatia Gordurosa não Alcoólica/complicações , Hepatopatia Gordurosa não Alcoólica/epidemiologia , Estudos Transversais , Apneia Obstrutiva do Sono/complicações , Apneia Obstrutiva do Sono/epidemiologia , Fatores de Risco
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