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1.
Ophthalmol Ther ; 2024 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-39133375

RESUMO

INTRODUCTION: The purpose of this study is to identify the factors affecting neovascular age-related macular degeneration (nAMD) disease stability after brolucizumab treatment. METHODS: We retrospectively analyzed the medical records of 31 patients (31 eyes) with recalcitrant nAMD who were switched to brolucizumab after conventional anti-vascular endothelial growth factor (VEGF) treatment. We divided patients into two groups by treatment extension (TE) period: group 1 with TE < 12 weeks (N = 16) and group 2 with TE ≥ 12 weeks (N = 15). We compared outcomes between the groups at 2, 4, 8, and 12 weeks, including morphological characteristics of choroidal neovascularization (CNV). Logistic regression analysis identified factors associated with TE ≥ 12 weeks. RESULTS: Group 2 had a significantly greater proportion of patients with dry macula (subretinal and intraretinal fluids absent) than group 1 (60 vs. 12.5%) at 2 weeks (P < 0.05). Best-corrected visual acuity (BCVA) and subfoveal choroidal thickness (SFCT) did not differ significantly between groups at all timepoints. Central subfield retinal thickness (CST) was significantly lower in group 2 at 2 (237.1 vs. 280.8 µm; P < 0.05), 4 (224.0 vs. 262.9 µm; P < 0.05), and 8 weeks (216.8 vs. 331.1 µm; P < 0.05). Group 2 had less vessel area (0.63 vs. 1.27 mm2; P < 0.05) and total vessel length (0.22 vs. 0.42 mm; P < 0.05). Choriocapillaris flow deficit (CCFd) was significantly lower in group 2 (42.7 vs. 48.2%; P < 0.05). Dry macula at 2 weeks (odds ratio [OR] = 8.3; P < 0.05) and a lower CCFd (OR = 0.73; P < 0.05) were associated with TE ≥ 12 weeks. CONCLUSIONS: Early fluid-free status after switching to brolucizumab and choriocapillary function around CNV were prognostic factors for disease stability in nAMD refractory to anti-VEGF treatment.

2.
ACS Nano ; 2024 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-39172688

RESUMO

Tin-lead (Sn-Pb) perovskite solar cells (PSCs) hold considerable potential for achieving efficiencies near the Shockley-Queisser (S-Q) limit. Notably, the inverted structure stands as the preferred fabrication method for the most efficient Sn-Pb PSCs. In this regard, it is imperative to implement a strategic customization of the hole selective layer to facilitate carrier extraction and refine the quality of perovskite films, which requires effective hole selectivity and favorable interactions with Sn-Pb perovskites. Herein, we propose the development of Co-Self-Assembled Monolayers (Co-SAM) by integrating both [2-(9H-carbazol-9-yl)ethyl]phosphonic acid (2PACz) and glycine at the buried contacts. The one-step deposition process employed in the fabrication of the Co-SAM ensures uniform coverage, resulting in a homogeneous surface potential. This is attributed to the molecular interactions occurring between 2PACz and glycine in the processing solution. Furthermore, the amine (-NH2) and ammonium (-NH3+) groups in glycine effectively passivate Sn4+ defects at the buried interface of Sn-Pb perovskite films, even under thermal stress. Consequently, the synergistic buried interface regulation of Co-SAM leads to a power conversion efficiency (PCE) of 23.46%, which outperforms devices modified with 2PACz or glycine alone. The Co-SAM-modified Sn-Pb PSC demonstrates enhanced thermal stability, maintaining 88% of its initial PCE under 65 °C thermal stress for 590 h.

3.
Cell Stem Cell ; 31(8): 1113-1126.e6, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-38981471

RESUMO

Emerging human pluripotent stem cell (hPSC)-based embryo models are useful for studying human embryogenesis. Particularly, there are hPSC-based somitogenesis models using free-floating culture that recapitulate somite formation. Somitogenesis in vivo involves intricately orchestrated biochemical and biomechanical events. However, none of the current somitogenesis models controls biochemical gradients or biomechanical signals in the culture, limiting their applicability to untangle complex biochemical-biomechanical interactions that drive somitogenesis. Herein, we develop a human somitogenesis model by confining hPSC-derived presomitic mesoderm (PSM) tissues in microfabricated trenches. Exogenous microfluidic morphogen gradients imposed on the PSM tissues cause axial patterning and trigger spontaneous rostral-to-caudal somite formation. A mechanical theory is developed to explain the size dependency between somites and the PSM. The microfluidic somitogenesis model is further exploited to reveal regulatory roles of cellular and tissue biomechanics in somite formation. This study presents a useful microengineered, hPSC-based model for understanding the biochemical and biomechanical events that guide somite formation.


Assuntos
Microfluídica , Modelos Biológicos , Células-Tronco Pluripotentes , Somitos , Humanos , Células-Tronco Pluripotentes/citologia , Células-Tronco Pluripotentes/metabolismo , Somitos/citologia , Somitos/metabolismo , Microfluídica/métodos , Desenvolvimento Embrionário , Mesoderma/citologia , Diferenciação Celular
4.
Nat Commun ; 15(1): 5055, 2024 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-38871742

RESUMO

The anterior-posterior axis of the mammalian embryo is laid down by the anterior visceral endoderm (AVE), an extraembryonic signaling center that is specified within the visceral endoderm. Current models posit that AVE differentiation is promoted globally by epiblast-derived Nodal signals, and spatially restricted by a BMP gradient established by the extraembryonic ectoderm. Here, we report spatially restricted AVE differentiation in bilayered embryo-like aggregates made from mouse embryonic stem cells that lack an extraembryonic ectoderm. Notably, clusters of AVE cells also form in pure visceral endoderm cultures upon activation of Nodal signaling, indicating that tissue-intrinsic factors can restrict AVE differentiation. We identify ß-catenin activity as a tissue-intrinsic factor that antagonizes AVE-inducing Nodal signals. Together, our results show how an AVE-like population can arise through interactions between epiblast and visceral endoderm alone. This mechanism may be a flexible solution for axis patterning in a wide range of embryo geometries, and provide robustness to axis patterning when coupled with signal gradients.


Assuntos
Padronização Corporal , Diferenciação Celular , Endoderma , Proteína Nodal , Transdução de Sinais , beta Catenina , Animais , Endoderma/citologia , Endoderma/metabolismo , Endoderma/embriologia , beta Catenina/metabolismo , Camundongos , Proteína Nodal/metabolismo , Proteína Nodal/genética , Camadas Germinativas/metabolismo , Camadas Germinativas/citologia , Células-Tronco Embrionárias Murinas/metabolismo , Células-Tronco Embrionárias Murinas/citologia , Regulação da Expressão Gênica no Desenvolvimento , Embrião de Mamíferos/citologia
5.
Environ Sci Technol ; 58(24): 10729-10739, 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38829283

RESUMO

Per- and polyfluoroalkyl substances (PFASs) have been detected in an array of environmental media due to their ubiquitous use in industrial and consumer products as well as potential release from fluorochemical manufacturing facilities. During their manufacture, many fluorotelomer (FT) facilities rely on neutral intermediates in polymer production including the FT-alcohols (FTOHs). These PFAS are known to transform to the terminal acids (perfluoro carboxylic acids; PFCAs) at rates that vary with environmental conditions. In the current study on soils from a FT facility, we employed gas chromatography coupled with conventional- and high-resolution mass spectrometry (GC-MS and GC-HRMS) to investigate the profile of these precursor compounds, the intermediary secondary alcohols (sFTOHs), FT-acrylates (FTAcr), and FT-acetates (FTAce) in soils around the former FT-production facility. Of these precursors, the general trend in detection intensity was [FTOHs] > [sFTOHs] > [FTAcrs], while for the FTOHs, homologue intensities generally were [12:2 FTOH] > [14:2 FTOH] > [16:2 FTOH] > [10:2 FTOH] > [18:2 FTOH] > [20:2 FTOH] > [8:2 FTOH] ∼ [6:2 FTOH]. The corresponding terminal acids were also detected in all soil samples and positively correlated with the precursor concentrations. GC-HRMS confirmed the presence of industrial manufacturing byproducts such as FT-ethers and FT-esters and aided in the tentative identification of previously unreported dimers and other compounds. The application of GC-HRMS to the measurement and identification of precursor PFAS is in its infancy, but the methodologies described here will help refine its use in tentatively identifying these compounds in the environment.


Assuntos
Fluorocarbonos , Poluentes do Solo , Solo , Poluentes do Solo/análise , Solo/química , Fluorocarbonos/análise , Cromatografia Gasosa-Espectrometria de Massas , Monitoramento Ambiental , Instalações Industriais e de Manufatura
6.
Biomedicines ; 12(5)2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38790906

RESUMO

2-Deoxy-2-[18F]fluoro-d-glucose (FDG) uptake of the reticuloendothelial system on positron emission tomography/computed tomography (PET/CT) is known to be related to systemic inflammatory response to cancer cells in patients with diverse malignancies. This retrospective study aimed to investigate whether FDG uptake by the reticuloendothelial system had a prognostic value in predicting progression-free survival (PFS) and overall survival (OS) in 138 cholangiocarcinoma patients. Quantifying FDG uptake of the aorta, bone marrow (BM), liver, and spleen from staging FDG PET/CT images, we found significant correlations between the BM-to-aorta uptake ratio (BAR), spleen-to-aorta uptake ratio, and BM-to-liver uptake ratio with tumor stage and serum inflammatory markers. In the multivariate survival analysis, BAR was an independent predictor of PFS (p = 0.016; hazard ratio, 2.308) and OS (p = 0.030; hazard ratio, 2.645). Patients with stages III-IV of the disease and a high BAR exhibited low 1-year PFS (35.8%) and OS (60.2%) rates, while those with stages I-II of the disease and low BAR showed robust rates of 90.0% and 96.7%, respectively. BAR measured on staging FDG PET/CT might be a potential imaging biomarker offering insights into the systemic inflammatory response and predicting prognosis in cholangiocarcinoma. This study highlights BAR as a promising, independent predictor with potential for personalized prognostication and treatment strategies.

7.
Int J Mol Sci ; 25(7)2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38612748

RESUMO

Visceral adiposity is known to be related to poor prognosis in patients with cholangiocarcinoma; however, the prognostic significance of the qualitative features of adipose tissue in cholangiocarcinoma has yet to be well defined. This study investigated the prognostic impact of adipose tissue imaging parameters reflecting the quantity and qualitative characteristics of subcutaneous (SAT) and visceral (VAT) adipose tissue on recurrence-free survival (RFS) and overall survival (OS) in 94 patients undergoing resection of cholangiocarcinoma. The area, mean computed tomography (CT) attenuation, and mean 2-deoxy-2-[18F]fluoro-D-glucose (FDG) uptake of SAT and VAT on positron emission tomography (PET)/CT for staging work-up were measured, and the relationship of these adipose tissue imaging parameters with clinicopathological factors and survival was assessed. TNM stage, histologic grade, lymphovascular invasion, and the size of cholangiocarcinoma showed positive correlations with adipose tissue imaging parameters. Multivariate survival analysis demonstrated that the visceral-to-subcutaneous adipose tissue area ratio (VSR) (p = 0.024; hazard ratio, 1.718) and mean FDG uptake of VAT (p = 0.033; hazard ratio, 9.781) were significant predictors for RFS, but all of the adipose tissue imaging parameters failed to show statistical significance for predicting OS. In addition to visceral adiposity, FDG uptake of VAT might be a promising prognostic parameter for predicting RFS in patients with cholangiocarcinoma.


Assuntos
Neoplasias dos Ductos Biliares , Colangiocarcinoma , Humanos , Fluordesoxiglucose F18 , Gordura Intra-Abdominal/diagnóstico por imagem , Prognóstico , Tomografia Computadorizada por Raios X , Colangiocarcinoma/diagnóstico por imagem , Colangiocarcinoma/cirurgia , Neoplasias dos Ductos Biliares/diagnóstico por imagem , Neoplasias dos Ductos Biliares/cirurgia , Ductos Biliares Intra-Hepáticos
8.
Int J Biol Macromol ; 262(Pt 2): 130094, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38350583

RESUMO

This study used a unique approach by developing a bilayer system that can simultaneously accomplish non-adhesion, hemostatic, and tissue regenerative properties. In this system, agarose was used as a carrier material, with an agarose-TEMPO-oxidized cellulose nanofiber (TOCN), (AT) layer acting as a non-adhesion layer and an Agarose-Extracellular matrix, (AE) layer acting as a tissue regenerative layer. Thrombin was loaded on the AE layer as an initiator of the healing process, by hemostasis. AT 1:4 showed 79.3 % and AE 1:4 showed 84.66 % cell viability initially confirming the biocompatible nature of the layers. The AE layer showed cell attachment and proliferation on its surface whereas on the AT layer, cells are visible but no attachment was observed. Furthermore, in vivo analysis was conducted. The non-adhesive layer was grafted between the cecum and peritoneal wall which showed that (AT 1:4) displayed remarkable non-adhesion properties as compared to a commercial product and the non-treated group. Hemostasis and tissue regeneration ability were evaluated using rat liver models. The bleeding time of AE 1:4TH was recorded as 160 s and the blood loss was 5.6 g. The results showed that (AE 1:4) displayed effective regeneration ability in the liver model after two weeks.


Assuntos
Celulose Oxidada , Hemostáticos , Nanofibras , Ratos , Animais , Hemostáticos/farmacologia , Sefarose , Hidrogéis , Hemostasia , Aderências Teciduais , Matriz Extracelular
9.
Nature ; 628(8007): 391-399, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38408487

RESUMO

The human nervous system is a highly complex but organized organ. The foundation of its complexity and organization is laid down during regional patterning of the neural tube, the embryonic precursor to the human nervous system. Historically, studies of neural tube patterning have relied on animal models to uncover underlying principles. Recently, models of neurodevelopment based on human pluripotent stem cells, including neural organoids1-5 and bioengineered neural tube development models6-10, have emerged. However, such models fail to recapitulate neural patterning along both rostral-caudal and dorsal-ventral axes in a three-dimensional tubular geometry, a hallmark of neural tube development. Here we report a human pluripotent stem cell-based, microfluidic neural tube-like structure, the development of which recapitulates several crucial aspects of neural patterning in brain and spinal cord regions and along rostral-caudal and dorsal-ventral axes. This structure was utilized for studying neuronal lineage development, which revealed pre-patterning of axial identities of neural crest progenitors and functional roles of neuromesodermal progenitors and the caudal gene CDX2 in spinal cord and trunk neural crest development. We further developed dorsal-ventral patterned microfluidic forebrain-like structures with spatially segregated dorsal and ventral regions and layered apicobasal cellular organizations that mimic development of the human forebrain pallium and subpallium, respectively. Together, these microfluidics-based neurodevelopment models provide three-dimensional lumenal tissue architectures with in vivo-like spatiotemporal cell differentiation and organization, which will facilitate the study of human neurodevelopment and disease.


Assuntos
Padronização Corporal , Microfluídica , Tubo Neural , Humanos , Técnicas de Cultura de Células em Três Dimensões , Diferenciação Celular , Crista Neural/citologia , Crista Neural/embriologia , Tubo Neural/citologia , Tubo Neural/embriologia , Células-Tronco Pluripotentes/citologia , Prosencéfalo/citologia , Prosencéfalo/embriologia , Medula Espinal/citologia , Medula Espinal/embriologia
10.
Aging (Albany NY) ; 16(3): 2005-2025, 2024 02 07.
Artigo em Inglês | MEDLINE | ID: mdl-38329439

RESUMO

Adult stem cells are pivotal for maintaining tissue homeostasis, and their functional decline is linked to aging and its associated diseases, influenced by the niche cells' environment. Age- and cancer-related reduction of vitamin D and its receptor levels are well documented in human clinical studies. However, the mechanisms through which the vitamin D/vitamin D receptor pathway contributes to anti-aging and extends life expectancy are not well understood. In this study, we aimed to determine the protective role of the vitamin D/vitamin D receptor pathway in differentiated enterocytes (ECs) during intestinal stem cell (ISC) aging. By utilizing a well- established Drosophila midgut model for stem cell aging biology, we revealed that vitamin D receptor knockdown in ECs induced ISC proliferation, EC death, ISC aging, and enteroendocrine cell differentiation. Additionally, age- and oxidative stress-induced increases in ISC proliferation and centrosome amplification were reduced by vitamin D treatment. Our findings suggest a direct evidence of the anti-aging role of the vitamin D/vitamin D receptor pathway and provides insights into the molecular mechanisms underlying healthy aging in Drosophila.


Assuntos
Proteínas de Drosophila , Drosophila , Animais , Humanos , Drosophila/fisiologia , Vitamina D/farmacologia , Vitamina D/metabolismo , Receptores de Calcitriol/genética , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Envelhecimento/metabolismo , Intestinos , Diferenciação Celular/fisiologia , Proliferação de Células , Drosophila melanogaster/metabolismo
11.
bioRxiv ; 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37961125

RESUMO

Emerging human pluripotent stem cell (hPSC)-based embryo models are useful for studying human embryogenesis. Particularly, there are hPSC-based somitogenesis models using free-floating culture that recapitulate somite formation. Somitogenesis in vivo involves intricately orchestrated bio-chemical and -mechanical events. However, none of the current somitogenesis models controls biochemical gradients or biomechanical signals in the culture, limiting their applicability to untangle complex biochemical-biomechanical interactions that drive somitogenesis. Here we report a new human somitogenesis model by confining hPSC-derived presomitic mesoderm (PSM) tissues in microfabricated trenches. Exogenous microfluidic morphogen gradients imposed on PSM cause axial patterning and trigger spontaneous rostral-to-caudal somite formation. A mechanical theory is developed to explain the size dependency between somites and PSM. The microfluidic somitogenesis model is further exploited to reveal regulatory roles of cellular and tissue biomechanics in somite formation. This study presents a useful microengineered, hPSC-based model for understanding the bio-chemical and -mechanical events that guide somite formation.

12.
Ann Surg Treat Res ; 105(5): 297-309, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38023431

RESUMO

Purpose: Immune checkpoint inhibitors (ICIs) have been shown significant oncological improvements in several cancers. However, ICIs are still in their infancy in hepatocellular carcinoma (HCC). Programmed cell death-ligand 1 (PD-L1), tumor-infiltrating lymphocytes (TILs), and epithelial-mesenchymal transition (EMT) have been known as prognostic factors in HCC. Therefore, we have focused on identifying the molecular mechanisms between each marker to evaluate a predictive role. Methods: Formalin-fixed paraffin-embedded samples were obtained from 166 patients with HCC who underwent surgery. The expression of PD-L1 and TILs and EMT marker were evaluated by immunohistochemical analysis. Results: The multivariate analysis showed that TIL expression (hazard ratio [HR], 0.483; 95% confidence interval [CI], 0.269-0.866; P = 0.015) were independent prognostic factors for overall survival. The prognostic factors for disease-free survival were EMT marker expression (HR, 1.565; 95% CI, 1.019-2.403; P = 0.005). Patients with high expression of TILs had significantly better survival compared to patients with low expression (P = 0.023). Patients who were TIL+/EMT- showed a significantly better prognosis than those who were TIL-/EMT+ (P = 0.049). Conclusion: This study demonstrates that PD-L1 expression of TILs is closely associated with EMT marker expression in HCC. Clinical investigations using anti-PD-1/PD-L1 inhibitors in patients with EMT-associated PD-L1 upregulation are warranted.

13.
ACS Appl Mater Interfaces ; 15(41): 48406-48415, 2023 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-37805990

RESUMO

This research explores the alteration of metal-organic frameworks (MOFs) using a method called postsynthetic metal exchange. We focus on the shift from a Zn-based MOF containing a [Zn4O(COO)6] secondary building unit (SBU) of octahedral site symmetry (ANT-1(Zn)) to a Fe-based one with a [Fe3IIIO(COO)6]+ SBU of trigonal prismatic site symmetry (ANT-1(Fe)). The symmetry-mismatched SBU transformation cleverly maintains the MOF's overall structure by adjusting the conformation of the flexible 1,3,5-benzenetribenzoate linker to alleviate the framework strain. The process triggers a decrease in the framework volume and pore size alongside a change in the framework's charge. These alterations influence the MOF's ability to adsorb gas and dye. During the transformation, core-shell MOFs (ANT-1(Zn@Fe)) are formed as intermediate products, demonstrating unique gas sorption traits and adjusted dye adsorption preferences due to the structural modifications at the core-shell interface. Heteronuclear clusters, located at the framework interfaces, enhance the heat of CO2 adsorption. Furthermore, they also influence the selectivity of the dye size. This research provides valuable insights into fabricating novel MOFs with unique properties by modifying the SBU of a MOF with flexible organic linkers from one site symmetry to another.

14.
Molecules ; 28(18)2023 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-37764491

RESUMO

Hispidulin is a natural bioactive flavonoid that has been studied for its potential therapeutic properties, including its anti-inflammatory, antioxidant, and neuroprotective effects. The aim of this study was to explore whether hispidulin could inhibit the endothelial inflammation triggered by Porphyromonas gingivalis (P. gingivalis) lipopolysaccharide (LPS). The adhesion of monocytes to the vascular endothelium was evaluated through in vitro and ex vivo monocyte adhesion assays. We analyzed the migration of monocytes across the endothelial layer using a transmigration assay. The results showed that treatment with hispidulin decreased the P. gingivalis LPS-induced adhesion of monocytes to endothelial cells and their migration by suppressing the P. gingivalis LPS-triggered expression of intercellular adhesion molecule-1 (ICAM-1) through downregulating nuclear factor-қB (NF-қB). In addition, hispidulin inhibited P. gingivalis LPS-induced mitogen-activated protein kinases (MAPKs) and AKT in endothelial cells. Altogether, the results indicate that hispidulin suppresses the vascular inflammation induced by P. gingivalis LPS. Mechanistically, it prevents the adhesion of monocytes to the vascular endothelium and migration and inhibits NF-қB, MAPKs, and AKT signaling in endothelial cells.


Assuntos
Lipopolissacarídeos , Porphyromonas gingivalis , Humanos , Porphyromonas gingivalis/metabolismo , Lipopolissacarídeos/farmacologia , Células Endoteliais , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Monócitos , Inflamação/tratamento farmacológico , Inflamação/metabolismo , Molécula 1 de Adesão Intercelular/metabolismo , NF-kappa B/metabolismo
15.
Nat Commun ; 14(1): 4536, 2023 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-37669984

RESUMO

Classical novae are thermonuclear explosions in stellar binary systems, and important sources of 26Al and 22Na. While γ rays from the decay of the former radioisotope have been observed throughout the Galaxy, 22Na remains untraceable. Its half-life (2.6 yr) would allow the observation of its 1.275 MeV γ-ray line from a cosmic source. However, the prediction of such an observation requires good knowledge of its nucleosynthesis. The 22Na(p, γ)23Mg reaction remains the only source of large uncertainty about the amount of 22Na ejected. Its rate is dominated by a single resonance on the short-lived state at 7785.0(7) keV in 23Mg. Here, we propose a combined analysis of particle-particle correlations and velocity-difference profiles to measure femtosecond nuclear lifetimes. The application of this method to the study of the 23Mg states, places strong limits on the amount of 22Na produced in novae and constrains its detectability with future space-borne observatories.

16.
Dev Cell ; 58(21): 2292-2308.e6, 2023 11 06.
Artigo em Inglês | MEDLINE | ID: mdl-37591246

RESUMO

Basic helix-loop-helix genes, particularly proneural genes, are well-described triggers of cell differentiation, yet information on their dynamics is limited, notably in human development. Here, we focus on Neurogenin 3 (NEUROG3), which is crucial for pancreatic endocrine lineage initiation. By monitoring both NEUROG3 gene expression and protein in single cells using a knockin dual reporter in 2D and 3D models of human pancreas development, we show an approximately 2-fold slower expression of human NEUROG3 than that of the mouse. We observe heterogeneous peak levels of NEUROG3 expression and reveal through long-term live imaging that both low and high NEUROG3 peak levels can trigger differentiation into hormone-expressing cells. Based on fluorescence intensity, we statistically integrate single-cell transcriptome with dynamic behaviors of live cells and propose a data-mapping methodology applicable to other contexts. Using this methodology, we identify a role for KLK12 in motility at the onset of NEUROG3 expression.


Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos , Proteínas do Tecido Nervoso , Humanos , Animais , Camundongos , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/metabolismo , Pâncreas/metabolismo , Diferenciação Celular/genética , Sistema Endócrino/metabolismo
17.
PLoS One ; 18(6): e0287577, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37384629

RESUMO

Angiogenesis plays an essential role in various normal physiological processes, such as embryogenesis, tissue repair, and skin regeneration. Visfatin is a 52 kDa adipokine secreted by various tissues including adipocytes. It stimulates the expression of vascular endothelial growth factor (VEGF) and promotes angiogenesis. However, there are several issues in developing full-length visfatin as a therapeutic drug due to its high molecular weight. Therefore, the purpose of this study was to develop peptides, based on the active site of visfatin, with similar or superior angiogenic activity using computer simulation techniques.Initially, the active site domain (residues 181∼390) of visfatin was first truncated into small peptides using the overlapping technique. Subsequently, the 114 truncated small peptides were then subjected to molecular docking analysis using two docking programs (HADDOCK and GalaxyPepDock) to generate small peptides with the highest affinity for visfatin. Furthermore, molecular dynamics simulations (MD) were conducted to investigate the stability of the protein-ligand complexes by computing root mean square deviation (RSMD) and root mean square fluctuation(RMSF) plots for the visfatin-peptide complexes. Finally, peptides with the highest affinity were examined for angiogenic activities, such as cell migration, invasion, and tubule formation in human umbilical vein endothelial cells (HUVECs). Through the docking analysis of the 114 truncated peptides, we screened nine peptides with a high affinity for visfatin. Of these, we discovered two peptides (peptide-1: LEYKLHDFGY and peptide-2: EYKLHDFGYRGV) with the highest affinity for visfatin. In an in vitrostudy, these two peptides showed superior angiogenic activity compared to visfatin itself and stimulated mRNA expressions of visfatin and VEGF-A. These results show that the peptides generated by the protein-peptide docking simulation have a more efficient angiogenic activity than the original visfatin.


Assuntos
Proteínas Angiogênicas , Fator A de Crescimento do Endotélio Vascular , Humanos , Nicotinamida Fosforribosiltransferase , Simulação de Acoplamento Molecular , Células Endoteliais , Simulação de Dinâmica Molecular
18.
J Chem Phys ; 158(21)2023 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-37260005

RESUMO

The coupling between the symmetric (νs) and antisymmetric (νa) OD stretch modes of monomeric D2O in CHCl3 is investigated using polarization-dependent two-dimensional infrared (2D IR) spectroscopy supported by numerical 2D IR simulations based on the exciton-band theory. The relationship between the local modes' and the exciton states' parameters is systematically studied, including center frequencies, diagonal anharmonicities, coupling, and off-diagonal anharmonicity. The mean coupling between νs and νa is accurately evaluated to be -49.96 ± 0.14 cm-1. The degree of relaxation in the harmonic approximation is quantified, and the angle between the exciton-state dipoles is accurately evaluated to be 101.4° ± 3.6°. In addition, the effect of the local-mode frequency correlation on the resulting exciton-state frequency correlation and the spectral shape of the linear and 2D IR spectra are also investigated.

19.
J Craniofac Surg ; 34(8): 2395-2398, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37236614

RESUMO

The primary goal in the secondary correction of unilateral cleft lip nose deformity is to achieve symmetry of the nose and nostril. This study aimed to investigate the efficacy of freeing the lower lateral cartilage from the pyriform ligament through an intranasal Z-plasty incision on the vestibular web in adult patients with complete unilateral cleft lip and palate. Thirty-six patients with complete unilateral cleft lip and palate, who underwent open rhinoplasty between August 2014 and December 2021, were identified retrospectively. Five parameters for nose form and nostril symmetry were measured on basal views through 2-dimensional photographic analysis. The patients were divided into subgroups with or without septoplasty. Cleft-to-non-cleft ratios between the Z (13 patients) and non-Z groups (23 patients) were compared using the Mann-Whitney U test. The mean follow-up was 12.9 months (6-31 mo). In the Z group, there were significant differences between the preoperative and postoperative values for nostril angulation, regardless of septoplasty (all P <0.05). Despite septoplasty, significant differences in the postoperative changes in nostril angulation were found between the Z and non-Z groups (all P <0.05). Intranasal Z-plasty on the plica vestibularis is an effective technique for releasing the lower lateral cartilage, improving the nostril asymmetry in cleft lip nose deformity.


Assuntos
Fenda Labial , Fissura Palatina , Doenças Nasais , Rinoplastia , Adulto , Humanos , Fenda Labial/cirurgia , Fenda Labial/complicações , Estudos Retrospectivos , Fissura Palatina/cirurgia , Fissura Palatina/complicações , Nariz/cirurgia , Nariz/anormalidades , Rinoplastia/métodos , Cartilagem/transplante , Doenças Nasais/cirurgia , Resultado do Tratamento
20.
Metab Eng ; 78: 137-147, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37257683

RESUMO

Mycosporine-like amino acids (MAAs) are promising natural sunscreens mainly produced in marine organisms. Until now, metabolic engineering efforts to produce MAAs in heterologous hosts have mainly focused on shinorine production, and the low production levels are still not suitable for industrial applications. In this study, we successfully developed Saccharomyces cerevisiae strains that can efficiently produce various disubstituted MAAs, including shinorine, porphyra-334, and mycosporine-2-glycine (M2G), which are formed by conjugating serine, threonine, and glycine to mycosporine-glycine (MG), respectively. We first generated an MG-producing strain by multiple integration of the biosynthetic genes from cyanobacteria and applying metabolic engineering strategies to increase sedoheptulose-7-phosphate pool, a substrate for MG production. Next, five mysD genes from cyanobacteria, which encode D-Ala-D-Ala ligase homologues that conjugate an amino acid to MG, were introduced into the MG-producing strain to determine the substrate preference of each MysD enzyme. MysDs from Lyngbya sp., Nostoclinckia, and Euhalothece sp. showed high specificity toward serine, threonine, and glycine, resulting in efficient production of shinorine, porphyra-334, and M2G, respectively. This is the first report on the production of porphyra-334 and M2G in S. cerevisiae. Furthermore, we identified that the substrate specificity of MysD was determined by the omega loop region of 43-45 amino acids predicted based on its structural homology to a D-Ala-D-Ala ligase from Thermus thermophilus involved in peptidoglycan biosynthesis. The substrate specificities of two MysD enzymes were interchangeable by swapping the omega loop region. Using the engineered strain expressing mysD from Lyngbya sp. or N. linckia, up to 1.53 g/L shinorine or 1.21 g/L porphyra-334 was produced by fed-batch fermentation in a 5-L bioreactor, the highest titer reported so far. These results suggest that S. cerevisiae is a promising host for industrial production of different types of MAAs, providing a sustainable and eco-friendly alternative for the development of natural sunscreens.


Assuntos
Cianobactérias , Saccharomyces cerevisiae , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Protetores Solares/química , Protetores Solares/metabolismo , Glicina/metabolismo , Aminoácidos/metabolismo , Cianobactérias/metabolismo , Treonina , Serina/metabolismo
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