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1.
Nat Methods ; 20(3): 459-468, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36823335

RESUMO

Single-molecule localization microscopy in a typical wide-field setup has been widely used for investigating subcellular structures with super resolution; however, field-dependent aberrations restrict the field of view (FOV) to only tens of micrometers. Here, we present a deep-learning method for precise localization of spatially variant point emitters (FD-DeepLoc) over a large FOV covering the full chip of a modern sCMOS camera. Using a graphic processing unit-based vectorial point spread function (PSF) fitter, we can fast and accurately model the spatially variant PSF of a high numerical aperture objective in the entire FOV. Combined with deformable mirror-based optimal PSF engineering, we demonstrate high-accuracy three-dimensional single-molecule localization microscopy over a volume of ~180 × 180 × 5 µm3, allowing us to image mitochondria and nuclear pore complexes in entire cells in a single imaging cycle without hardware scanning; a 100-fold increase in throughput compared to the state of the art.


Assuntos
Aprendizado Profundo , Imageamento Tridimensional/métodos , Imagem Individual de Molécula/métodos
2.
Proc Natl Acad Sci U S A ; 120(8): e2216641120, 2023 02 21.
Artigo em Inglês | MEDLINE | ID: mdl-36780517

RESUMO

Microchromosomes are prevalent in nonmammalian vertebrates [P. D. Waters et al., Proc. Natl. Acad. Sci. U.S.A. 118 (2021)], but a few of them are missing in bird genome assemblies. Here, we present a new chicken reference genome containing all autosomes, a Z and a W chromosome, with all gaps closed except for the W. We identified ten small microchromosomes (termed dot chromosomes) with distinct sequence and epigenetic features, among which six were newly assembled. Those dot chromosomes exhibit extremely high GC content and a high level of DNA methylation and are enriched for housekeeping genes. The pericentromeric heterochromatin of dot chromosomes is disproportionately large and continues to expand with the proliferation of satellite DNA and testis-expressed genes. Our analyses revealed that the 41-bp CNM repeat frequently forms higher-order repeats (HORs) at the centromeres of acrocentric chromosomes. The centromere core regions where the kinetochore attaches often encompass telomeric sequence (TTAGGG)n, and in a one of the dot chromosomes, the centromere core recruits an endogenous retrovirus (ERV). We further demonstrate that the W chromosome shares some common features with dot chromosomes, having large arrays of hypermethylated tandem repeats. Finally, using the complete chicken chromosome models, we reconstructed a fine picture of chordate karyotype evolution, revealing frequent chromosomal fusions before and after vertebrate whole-genome duplications. Our sequence and epigenetic characterization of chicken chromosomes shed insights into the understanding of vertebrate genome evolution and chromosome biology.


Assuntos
Centrômero , Galinhas , Animais , Masculino , Galinhas/genética , Centrômero/genética , Telômero , Heterocromatina , Sequências de Repetição em Tandem
3.
Proc Natl Acad Sci U S A ; 120(10): e2201504120, 2023 03 07.
Artigo em Inglês | MEDLINE | ID: mdl-36867684

RESUMO

The slow-evolving invertebrate amphioxus has an irreplaceable role in advancing our understanding of the vertebrate origin and innovations. Here we resolve the nearly complete chromosomal genomes of three amphioxus species, one of which best recapitulates the 17 chordate ancestor linkage groups. We reconstruct the fusions, retention, or rearrangements between descendants of whole-genome duplications, which gave rise to the extant microchromosomes likely existed in the vertebrate ancestor. Similar to vertebrates, the amphioxus genome gradually establishes its three-dimensional chromatin architecture at the onset of zygotic activation and forms two topologically associated domains at the Hox gene cluster. We find that all three amphioxus species have ZW sex chromosomes with little sequence differentiation, and their putative sex-determining regions are nonhomologous to each other. Our results illuminate the unappreciated interspecific diversity and developmental dynamics of amphioxus genomes and provide high-quality references for understanding the mechanisms of chordate functional genome evolution.


Assuntos
Anfioxos , Animais , Cromatina , Cromossomos Sexuais , Rearranjo Gênico , Família Multigênica
4.
Plant J ; 2024 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-38972041

RESUMO

Diurnal flower-opening time (DFOT), the time of spikelet opening during the day, is an important trait for hybrid rice (Oryza sativa L.) seed production. Hybrids between indica and japonica rice varieties have strong heterosis, but the parental lines usually have different, nonoverlapping DFOTs. This reduces the success of hybrid seed production in crosses between indica and japonica subspecies, thus hindering the utilization of indica and japonica inter-subspecies heterosis. However, little is known about the molecular mechanisms regulating DFOT in rice. Here, we obtained japonica rice lines with a DFOT 1.5 h earlier than the wild type by overexpressing OsMYC2, a gene encoding a key transcription factor in the jasmonate (JA) signaling pathway. OsMYC2 is activated by JA signaling and directly regulates the transcription of genes related to JA biosynthesis and cell wall metabolism. Overexpressing OsMYC2 led to significantly increased JA contents and decreased cellulose and hemicellulose contents in lodicule cells, as well as the softening of lodicule cell walls. This may facilitate the swelling of lodicules, resulting in early diurnal flower-opening. These results suggest that the OsMYC2-JA feedback loop regulates DFOT in rice via cell wall remodeling. These findings shed light on the understanding of regulatory mechanism of the DFOT of plants, which should promote the development of indica and japonica varieties suitable for hybrid rice breeding.

5.
Cell Mol Life Sci ; 81(1): 331, 2024 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-39107572

RESUMO

The rising incidences of atherosclerosis have necessitated efforts to identify novel targets for therapeutic interventions. In the present study, we observed increased expression of the mechanosensitive calcium channel Piezo1 transcript in mouse and human atherosclerotic plaques, correlating with infiltration of PIEZO1-expressing macrophages. In vitro administration of Yoda1, a specific agonist for PIEZO1, led to increased foam cell apoptosis and enhanced phagocytosis by macrophages. Mechanistically, PIEZO1 activation resulted in intracellular F-actin rearrangement, elevated mitochondrial ROS levels and induction of mitochondrial fragmentation upon PIEZO1 activation, as well as increased expression of anti-inflammatory genes. In vivo, ApoE-/- mice treated with Yoda1 exhibited regression of atherosclerosis, enhanced stability of advanced lesions, reduced plaque size and necrotic core, increased collagen content, and reduced expression levels of inflammatory markers. Our findings propose PIEZO1 as a novel and potential therapeutic target in atherosclerosis.


Assuntos
Apoptose , Aterosclerose , Células Espumosas , Canais Iônicos , Macrófagos , Fagocitose , Animais , Canais Iônicos/metabolismo , Canais Iônicos/genética , Aterosclerose/metabolismo , Aterosclerose/patologia , Aterosclerose/genética , Camundongos , Células Espumosas/metabolismo , Células Espumosas/patologia , Humanos , Macrófagos/metabolismo , Camundongos Endogâmicos C57BL , Tiofenos/farmacologia , Masculino , Espécies Reativas de Oxigênio/metabolismo , Placa Aterosclerótica/patologia , Placa Aterosclerótica/metabolismo , Placa Aterosclerótica/genética , Mitocôndrias/metabolismo , Pirazinas , Tiadiazóis
6.
PLoS Genet ; 18(6): e1010229, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35696369

RESUMO

The regulation of glycometabolism homeostasis is vital to maintain health and development of animal and humans; however, the molecular mechanisms by which organisms regulate the glucose metabolism homeostasis from a feeding state switching to a non-feeding state are not fully understood. Using the holometabolous lepidopteran insect Helicoverpa armigera, cotton bollworm, as a model, we revealed that the steroid hormone 20-hydroxyecdysone (20E) upregulated the expression of transcription factor Krüppel-like factor (identified as Klf15) to promote macroautophagy/autophagy, apoptosis and gluconeogenesis during metamorphosis. 20E via its nuclear receptor EcR upregulated Klf15 transcription in the fat body during metamorphosis. Knockdown of Klf15 using RNA interference delayed pupation and repressed autophagy and apoptosis of larval fat body during metamorphosis. KLF15 promoted autophagic flux and transiting to apoptosis. KLF15 bound to the KLF binding site (KLF bs) in the promoter of Atg8 (autophagy-related gene 8/LC3) to upregulate Atg8 expression. Knockdown Atg8 reduced free fatty acids (FFAs), glycerol, free amino acids (FAAs) and glucose levels. However, knockdown of Klf15 accumulated FFAs, glycerol, and FAAs. Glycolysis was switched to gluconeogenesis, trehalose and glycogen synthesis were changed to degradation during metamorphosis, which were accompanied by the variation of the related genes expression. KLF15 upregulated phosphoenolpyruvate carboxykinase (Pepck) expression by binding to KLF bs in the Pepck promoter for gluconeogenesis, which utilised FFAs, glycerol, and FAAs directly or indirectly to increase glucose in the hemolymph. Taken together, 20E via KLF15 integrated autophagy and gluconeogenesis by promoting autophagy-related and gluconeogenesis-related genes expression.


Assuntos
Ecdisterona , Mariposas , Animais , Autofagia/genética , Ecdisterona/metabolismo , Técnicas de Silenciamento de Genes , Gluconeogênese/genética , Glucose/metabolismo , Glicerol/metabolismo , Homeostase/genética , Proteínas de Insetos/genética , Proteínas de Insetos/metabolismo , Fatores de Transcrição Kruppel-Like/genética , Fatores de Transcrição Kruppel-Like/metabolismo , Mariposas/genética
7.
Genomics ; 116(3): 110832, 2024 05.
Artigo em Inglês | MEDLINE | ID: mdl-38518898

RESUMO

GCN2-eIF2α signaling pathway plays crucial roles in cell growth,development, and protein synthesis. However, in polyploid fish, the function of this pathway is rarely understood. In this study, genes associated with the GCN2-eIF2α pathway (pkr, pek, gcn2, eif2α) are founded lower expression levels in the triploid crucian carp (3nCC) muscle compared to that of the red crucian carp (RCC). In muscle effect stage embryos of the 3nCC, the mRNA levels of this pathway genes are generally lower than those of RCC, excluding hri and fgf21. Inhibiting gcn2 in 3nCC embryos downregulates downstream gene expression (eif2α, atf4, fgf21), accelerating embryonic development. In contrast, overexpressing of eif2α can alter the expression levels of downstream genes (atf4 and fgf21), and decelerates the embryonic development. These results demonstrate the GCN2-eIF2α pathway's regulatory impact on 3nCC growth, advancing understanding of fish rapid growth genetics and offering useful molecular markers for breeding of excellent strains.


Assuntos
Carpas , Fator de Iniciação 2 em Eucariotos , Proteínas de Peixes , Transdução de Sinais , Animais , Carpas/genética , Carpas/metabolismo , Carpas/crescimento & desenvolvimento , Fator de Iniciação 2 em Eucariotos/metabolismo , Fator de Iniciação 2 em Eucariotos/genética , Proteínas de Peixes/genética , Proteínas de Peixes/metabolismo , Triploidia , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Serina-Treonina Quinases/genética , Fator 4 Ativador da Transcrição/metabolismo , Fator 4 Ativador da Transcrição/genética , Regulação da Expressão Gênica no Desenvolvimento , Desenvolvimento Embrionário/genética
8.
Gut ; 73(7): 1169-1182, 2024 06 06.
Artigo em Inglês | MEDLINE | ID: mdl-38395437

RESUMO

OBJECTIVE: Hepatitis B virus (HBV)-related hepatocellular carcinoma (HCC), mostly characterised by HBV integrations, is prevalent worldwide. Previous HBV studies mainly focused on a few hotspot integrations. However, the oncogenic role of the other HBV integrations remains unclear. This study aimed to elucidate HBV integration-induced tumourigenesis further. DESIGN: Here, we illuminated the genomic structures encompassing HBV integrations in 124 HCCs across ages using whole genome sequencing and Nanopore long reads. We classified a repertoire of integration patterns featured by complex genomic rearrangement. We also conducted a clustered regularly interspaced short palindromic repeat (CRISPR)-based gain-of-function genetic screen in mouse hepatocytes. We individually activated each candidate gene in the mouse model to uncover HBV integration-mediated oncogenic aberration that elicits tumourigenesis in mice. RESULTS: These HBV-mediated rearrangements are significantly enriched in a bridge-fusion-bridge pattern and interchromosomal translocations, and frequently led to a wide range of aberrations including driver copy number variations in chr 4q, 5p (TERT), 6q, 8p, 16q, 9p (CDKN2A/B), 17p (TP53) and 13q (RB1), and particularly, ultra-early amplifications in chr8q. Integrated HBV frequently contains complex structures correlated with the translocation distance. Paired breakpoints within each integration event usually exhibit different microhomology, likely mediated by different DNA repair mechanisms. HBV-mediated rearrangements significantly correlated with young age, higher HBV DNA level and TP53 mutations but were less prevalent in the patients subjected to prior antiviral therapies. Finally, we recapitulated the TONSL and TMEM65 amplification in chr8q led by HBV integration using CRISPR/Cas9 editing and demonstrated their tumourigenic potentials. CONCLUSION: HBV integrations extensively reshape genomic structures and promote hepatocarcinogenesis (graphical abstract), which may occur early in a patient's life.


Assuntos
Carcinoma Hepatocelular , Vírus da Hepatite B , Neoplasias Hepáticas , Integração Viral , Carcinoma Hepatocelular/virologia , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/virologia , Neoplasias Hepáticas/patologia , Vírus da Hepatite B/genética , Humanos , Integração Viral/genética , Animais , Camundongos , Masculino , Pessoa de Meia-Idade , Feminino , Adulto , Sequenciamento Completo do Genoma , Variações do Número de Cópias de DNA , Idoso
9.
Mol Biol Evol ; 40(1)2023 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-36578180

RESUMO

Unlike birds and mammals, many teleosts have homomorphic sex chromosomes, and changes in the chromosome carrying the sex-determining locus, termed "turnovers", are common. Recent turnovers allow studies of several interesting questions. One question is whether the new sex-determining regions evolve to become completely non-recombining, and if so, how and why. Another is whether (as predicted) evolutionary changes that benefit one sex accumulate in the newly sex-linked region. To study these questions, we analyzed the genome sequences of two seahorse species of the Syngnathidae, a fish group in which many species evolved a unique structure, the male brood pouch. We find that both seahorse species have XY sex chromosome systems, but their sex chromosome pairs are not homologs, implying that at least one turnover event has occurred. The Y-linked regions occupy 63.9% and 95.1% of the entire sex chromosome of the two species and do not exhibit extensive sequence divergence with their X-linked homologs. We find evidence for occasional recombination between the extant sex chromosomes that may account for their homomorphism. We argue that these Y-linked regions did not evolve by recombination suppression after the turnover, but by the ancestral nature of the low crossover rates in these chromosome regions. With such an ancestral crossover landscape, a turnover can instantly create an extensive Y-linked region. Finally, we test for adaptive evolution of male pouch-related genes after they became Y-linked in the seahorse.


Assuntos
Smegmamorpha , Animais , Gravidez , Feminino , Smegmamorpha/genética , Evolução Molecular , Cromossomos Sexuais/genética , Genoma , Mamíferos/genética
10.
Cancer Sci ; 115(6): 1749-1762, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38508217

RESUMO

N6-Methyladenosine (m6A) is a important process regulating gene expression post-transcriptionally. Programmed death ligand 1 (PD-L1) is a major immune inhibitive checkpoint that facilitates immune evasion and is expressed in tumor cells. In this research we discovered that Wilms' tumor 1-associated protein (WTAP) degradation caused by ubiquitin-mediated cleavage in cancer cells (colorectal cancer, CRC) under hypoxia was inhibited by Pumilio homolog 1 (PUM1) directly bound to WTAP. WTAP enhanced PD-L1 expression in a way that was m6A-dependent. m6A "reader," Insulin-like growth factor 2 mRNA-binding protein 2 (IGF2BP2) identified methylated PD-L1 transcripts and subsequently fixed its mRNA. Additionally, we found that T-cell proliferation and its cancer cell-killing effects were prevented by overexpression of WTAP in vitro and in vivo. Overexpression prevented T cells from proliferating and killing CRC by maintaining the expression of PD-L1. Further evidence supporting the WTAP-PD-L1 regulatory axis was found in human CRC and organoid tissues. Tumors with high WTAP levels appeared more responsive to anti-PD1 immunotherapy, when analyzing samples from patients undergoing treatment. Overall, our findings demonstrated a novel PD-L1 regulatory mechanism by WTAP-induced mRNA epigenetic regulation and the possible application of targeting WTAP as immunotherapy for tumor hypoxia.


Assuntos
Adenosina , Antígeno B7-H1 , Neoplasias Colorretais , Humanos , Adenosina/análogos & derivados , Adenosina/metabolismo , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Neoplasias Colorretais/imunologia , Neoplasias Colorretais/metabolismo , Antígeno B7-H1/metabolismo , Antígeno B7-H1/genética , Animais , Camundongos , Linhagem Celular Tumoral , Proteínas de Ligação a RNA/metabolismo , Proteínas de Ligação a RNA/genética , Linfócitos T/imunologia , Linfócitos T/metabolismo , Proliferação de Células , Regulação Neoplásica da Expressão Gênica , Fatores de Processamento de RNA/genética , Fatores de Processamento de RNA/metabolismo , Feminino , Hipóxia Tumoral/genética , Proteínas de Ciclo Celular
11.
Am Heart J ; 273: 72-82, 2024 07.
Artigo em Inglês | MEDLINE | ID: mdl-38621575

RESUMO

BACKGROUND: The reduction in cardiovascular disease (CVD) events with edetate disodium (EDTA) in the Trial to Assess Chelation Therapy (TACT) suggested that chelation of toxic metals might provide novel opportunities to reduce CVD in patients with diabetes. Lead and cadmium are vasculotoxic metals chelated by EDTA. We present baseline characteristics for participants in TACT2, a randomized, double-masked, placebo-controlled trial designed as a replication of the TACT trial limited to patients with diabetes. METHODS: TACT2 enrolled 1,000 participants with diabetes and prior myocardial infarction, age 50 years or older between September 2016 and December 2020. Among 959 participants with at least one infusion, 933 had blood and/or urine metals measured at the Centers for Diseases Control and Prevention using the same methodology as in the National Health and Nutrition Examination Survey (NHANES). We compared metal levels in TACT2 to a contemporaneous subset of NHANES participants with CVD, diabetes and other inclusion criteria similar to TACT2's participants. RESULTS: At baseline, the median (interquartile range, IQR) age was 67 (60, 72) years, 27% were women, 78% reported white race, mean (SD) BMI was 32.7 (6.6) kg/m2, 4% reported type 1 diabetes, 46.8% were treated with insulin, 22.3% with GLP1-receptor agonists or SGLT-2 inhibitors, 90.2% with aspirin, warfarin or P2Y12 inhibitors, and 86.5% with statins. Blood lead was detectable in all participants; median (IQR) was 9.19 (6.30, 13.9) µg/L. Blood and urine cadmium were detectable in 97% and median (IQR) levels were 0.28 (0.18, 0.43) µg/L and 0.30 (0.18, 0.51) µg/g creatinine, respectively. Metal levels were largely similar to those in the contemporaneous NHANES subset. CONCLUSIONS: TACT2 participants were characterized by high use of medication to treat CVD and diabetes and similar baseline metal levels as in the general US population. TACT2 will determine whether chelation therapy reduces the occurrence of subsequent CVD events in this high-risk population. CLINICAL TRIALS REGISTRATION: ClinicalTrials.gov. Identifier: NCT02733185. https://clinicaltrials.gov/study/NCT02733185.


Assuntos
Terapia por Quelação , Humanos , Feminino , Masculino , Pessoa de Meia-Idade , Idoso , Terapia por Quelação/métodos , Método Duplo-Cego , Ácido Edético/uso terapêutico , Chumbo/sangue , Chumbo/urina , Cádmio/urina , Cádmio/sangue , Quelantes/uso terapêutico , Doenças Cardiovasculares/prevenção & controle , Doenças Cardiovasculares/sangue
12.
Plant Biotechnol J ; 22(8): 2267-2281, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38526838

RESUMO

Inter-subspecific indica-japonica hybrid rice (Oryza sativa) has the potential for increased yields over traditional indica intra-subspecies hybrid rice, but limited yield of F1 hybrid seed production (FHSP) hinders the development of indica-japonica hybrid rice breeding. Diurnal flower-opening time (DFOT) divergence between indica and japonica rice has been a major contributing factor to this issue, but few DFOT genes have been cloned. Here, we found that manipulating the expression of jasmonate (JA) pathway genes can effectively modulate DFOT to improve the yield of FHSP in rice. Treating japonica cultivar Zhonghua 11 (ZH11) with methyl jasmonate (MeJA) substantially advanced DFOT. Furthermore, overexpressing the JA biosynthesis gene OPDA REDUCTASE 7 (OsOPR7) and knocking out the JA inactivation gene CHILLING TOLERANCE 1 (OsHAN1) in ZH11 advanced DFOT by 1- and 2-h respectively; and knockout of the JA signal suppressor genes JASMONATE ZIM-DOMAIN PROTEIN 7 (OsJAZ7) and OsJAZ9 resulted in 50-min and 1.5-h earlier DFOT respectively. The yields of FHSP using japonica male-sterile lines GAZS with manipulated JA pathway genes were significantly higher than that of GAZS wildtype. Transcriptome analysis, cytological observations, measurements of elastic modulus and determination of cell wall components indicated that the JA pathway could affect the loosening of the lodicule cell walls by regulating their composition through controlling sugar metabolism, which in turn influences DFOT. This research has vital implications for breeding japonica rice cultivars with early DFOT to facilitate indica-japonica hybrid rice breeding.


Assuntos
Ciclopentanos , Flores , Oryza , Oxilipinas , Oryza/genética , Oryza/metabolismo , Oryza/crescimento & desenvolvimento , Ciclopentanos/metabolismo , Oxilipinas/metabolismo , Flores/genética , Flores/metabolismo , Flores/crescimento & desenvolvimento , Regulação da Expressão Gênica de Plantas , Melhoramento Vegetal , Acetatos/farmacologia , Acetatos/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Reguladores de Crescimento de Plantas/metabolismo , Ritmo Circadiano/genética
13.
BMC Microbiol ; 24(1): 5, 2024 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-38172684

RESUMO

BACKGROUND: Harmonia axyridis is an effective natural enemy insect to a variety of phloem-sucking pests and Lepidopteran larvae, such as aphids, scabies, and phylloxera, while its industrial production is limited due to unmature artificial diet. Insect intestinal microbiota affect host development and reproduction. The aim of this study is to understand intestinal microbiota composition of H. axyridis and screen effective probiotics on artificial diet. Considering the role of the components and composition of the diet on the structure and composition of the intestinal microbiome, four kinds of diets were set up: (1) aphid; (2) basic diet; (3) basic diet + glucose; (4) basic diet + trehalose. The gut microbiota of H. axyridis was detected after feeding on different diets. RESULTS: Results showed that the gut microbiota between artificial diet group and aphid groups were far apart, while the basic and glucose groups were clearly clustered. Besides, the glucose group and trehalose group had one unique phylum, Cryptophyta and Candidatus Saccharibacteria, respectively. The highest abundance of Proteobacteria was found in the aphid diet. The highest abundance of Firmicutes was found in the basic diet. However, the addition of glucose or trehalose alleviated the change. In addition, the relative abundance of Enterobacter, Klebsiella, Enterobacteriaceae_unclassified, Enterobacteriales_unclassified and Serratia in the aphid group was higher than other groups. Moreover, the function of gut genes in each group also showed clear differences. CONCLUSION: These results have offered a strong link between artificial diets and gut microbes, and also have provided a theoretical basis for the screening of synergistic probiotics in artificial diet.


Assuntos
Afídeos , Besouros , Microbioma Gastrointestinal , Animais , Trealose , Insetos , Dieta , Enterobacter , Glucose
14.
Opt Lett ; 49(8): 2005-2008, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38621062

RESUMO

A method by detecting the ellipse fitting degree of the trajectory equation formed by two self-mixing (SM) signals in the multi-longitudinal mode laser SM system with a Wollaston prism is presented to test the free spectral range (FSR) of the laser. By utilizing the orthogonal vector and phase-shift characteristics between adjacent longitudinal modes, the fluctuations in multi-mode SM effects caused by changes in the external cavity length are transformed into alterations in the trajectory composed of two orthogonal SM signals. The FSR is calculated by detecting the difference in external cavity lengths between the two positions, where the trajectory of the two SM signals best fits an ellipse. To achieve an automatic FSR measurement, the ellipse fitting degree is proposed as the criterion for positioning the external cavity mode. Experimental results indicate that the FSR of the laser diode is measured to be 85.23 GHz with a resolution of 0.48 GHz, while the corresponding external cavity resolution is 10 µm, and the resolution of the ellipse fitting degree is less than 1. The compact and straightforward design, coupled with high sensitivity, automated measurements, and immunity to optical feedback, holds significant promise as a robust tool for measuring FSR and assessing laser performance.

15.
Opt Lett ; 49(14): 4058-4061, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-39008776

RESUMO

A near-resonant excitation strategy is proposed and implemented in a 4-µm-thick GaN microcavity to realize an exciton-polariton condensate/lasing with low threshold. Strong exciton-photon coupling is demonstrated, and polariton lasing is realized with an ultra-low threshold excitation power density of about 13.3 W/cm2 at room temperature. Such an ultra-low threshold is ascribed to the implementation of the near-resonant optical excitation strategy, which enables acceleration of the exciton and polariton relaxation and suppression of the heat generation in the cavity, thereby reducing the energy loss and enhance the cavity excitation efficiency.

16.
FASEB J ; 37(8): e23071, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37389924

RESUMO

The sustained release of profibrotic cytokines, mainly transforming growth factor-ß (TGF-ß), leads to the occurrence of kidney fibrosis and chronic kidney disease (CKD). Connective tissue growth factor (CTGF) appears to be an alternative target to TGF-ß for antifibrotic therapy in CKD. In this study, we found that long noncoding RNA AI662270 was significantly increased in various renal fibrosis models. In vivo, ectopic expression of AI662270 alone was sufficient to activate interstitial fibroblasts and drive kidney fibrosis, whereas inhibition of AI662270 blocked the activation of interstitial fibroblasts and ameliorated kidney fibrosis in various murine models. Mechanistic studies revealed that overexpression of AI662270 significantly increased CTGF product, which was required for the role of AI662270 in driving kidney fibrosis. Furthermore, AI662270 binds to the CTGF promoter and directly interacts with METTL3, the methyltransferase of RNA N6 -methyladenosine (m6 A) modification. Functionally, AI662270-mediated recruitment of METTL3 increased the m6 A methylation of CTGF mRNA and consequently enhanced CTGF mRNA stability. In conclusion, our results support that AI662270 promotes CTGF expression at the posttranscriptional stage by recruiting METTL3 to the CTGF promoter and depositing m6 A modifications on the nascent mRNA, thereby, uncovering a novel regulatory mechanism of CTGF in the pathogenesis of kidney fibrosis.


Assuntos
RNA Longo não Codificante , Insuficiência Renal Crônica , Animais , Camundongos , Fator de Crescimento do Tecido Conjuntivo/genética , Rim , Metiltransferases/genética , RNA Longo não Codificante/genética , RNA Mensageiro/genética , Fator de Crescimento Transformador beta/genética
17.
Eur Radiol ; 34(4): 2244-2255, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37740779

RESUMO

OBJECTIVES: To assess the therapeutic response of HCC to antiangiogenic therapy plus immunotherapy by integrating RECIST 1.1 and alpha-fetoprotein (AFP) response at the 6th week to predict overall survival (OS). METHODS: This retrospective study included 150 and 214 patients with HCC who received combination therapy in training and validation cohorts. The medical images and AFP levels obtained at baseline and 6th week were collected. AFP response stratification: partial response (PR): AFP% ≥ 75% decline; stable disease (SD): AFP% < 75% decline and ≤ 10% elevation; progressive disease (PD): AFP% > 10% elevation. The alpha-RECIST was: PR: RECIST 1.1-PR or AFP-PR; PD: AFP-PD or RECIST 1.1-PD and does not satisfy AFP-PR; SD: neither PR nor PD. OS was compared using Kaplan-Meier curves. The predictive ability of various criteria was evaluated using the concordance index and time-dependent area under the receiver-operating characteristic curve. RESULTS: RECIST 1.1 achieved significant OS stratification (p = 0.020) for AFP < 20 ng/mL. For AFP ≥ 20 ng/mL, alpha-RECIST showed better performance than RECIST 1.1, mRECIST, and AFP response according to C-index (0.73 vs 0.66 vs 0.68 vs 0.69). The National Cancer Center (NCC) strategy utilized RECIST 1.1 for AFP < 20 ng/mL and alpha-RECIST for AFP ≥ 20 ng/mL and showed better performance than RECIST 1.1, mRECIST and AFP response according to C-index (0.73 vs 0.67 vs 0.69 vs 0.64). The performances of alpha-RECIST and NCC Strategy were confirmed in the validation cohort (C-index = 0.77 and 0.74). CONCLUSIONS: The alpha-RECIST and NCC Strategy achieved better survival stratification in patients with HCC under combination therapy in the AFP ≥ 20 ng/mL group and the whole cohort compared to the RECIST 1.1, mRECIST, and AFP response. CLINICAL TRANSLATIONAL RELEVANCE: The alpha-RECIST and National Cancer Center strategy are optimal methods for determining therapeutic response to a combination of anti-angiogenic therapy plus immunotherapy and facilitating accurate prognostic stratification for HCC in the AFP ≥ 20 ng/mL group and the whole cohort, which may help oncologists for early identification of responders and progression at 6 weeks and clinical decision-making. KEY POINTS: • RECIST 1.1 is indicated for patients with baseline alpha-fetoprotein (AFP) < 20 ng/mL. • For patients with baseline AFP ≥ 20 ng/mL, integrating RECIST 1.1 and AFP response (alpha-RECIST) may aid in the early identification of survival benefits and progression definition prior to the administration of additional efficacious drugs. • The National Cancer Center strategy is an optimal stratified strategy for determining therapeutic response to a combination of anti-angiogenic therapy and immunotherapy for HCC based on baseline AFP levels.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/terapia , Carcinoma Hepatocelular/tratamento farmacológico , alfa-Fetoproteínas , Neoplasias Hepáticas/terapia , Neoplasias Hepáticas/tratamento farmacológico , Critérios de Avaliação de Resposta em Tumores Sólidos , Estudos Retrospectivos , Imunoterapia
18.
Inorg Chem ; 63(22): 10264-10277, 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38761140

RESUMO

Exploring highly efficient and robust non-noble metal catalysts for VOC abatement is crucial but challenging. Mn-based perovskites are a class of redox catalysts with good thermal stability, but their activity in the catalytic combustion of light alkanes is insufficient. In this work, we modulated the Mn-O bond strength in a Mn-based perovskite via defect engineering, over which the catalytic activity of propane combustion was significantly enhanced. It demonstrates that the oxygen vacancy concentration and the Mn-O bond strength can be efficiently modulated by finely tuning the Ni content in SmNixMn1-xO3 perovskite catalysts (SNxM1-x), which in turn can enhance the redox ability and generate more active oxygen species. The SN0.10M0.90 catalyst with the lowest Mn-O bond strength exhibits the lowest apparent activation energy, over which the propane conversion rate increases by 3.6 times compared to that on the SmMnO3 perovskite catalyst (SM). In addition, a SN0.10M0.90/cordierite monolithic catalyst can also exhibit a remarkable catalytic performance and deliver excellent long-term durability (1000 h), indicating broad prospects in industrial applications. Moreover, the promotional effect of Ni substitution was further unveiled by density functional theory (DFT) calculations. This work brings a favorable guidance for the exploration of highly efficient perovskite catalysts for light alkane elimination.

19.
BMC Neurol ; 24(1): 55, 2024 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-38308217

RESUMO

OBJECTIVE: This study aims to evaluate the efficacy and safety of adjunctive hyperbaric oxygen therapy (HBOT) in acute ischaemic stroke (AIS) based on existing evidence. METHODS: We conducted a comprehensive search through April 15, 2023, of seven major databases for randomized controlled trials (RCTs) comparing adjunctive hyperbaric HBOT with non-HBOT (no HBOT or sham HBOT) treatments for AIS. Data extraction and assessment were independently performed by two researchers. The quality of included studies was evaluated using the tool provided by the Cochrane Collaboration. Meta-analysis was conducted using Rev Man 5.3. RESULTS: A total of 8 studies involving 493 patients were included. The meta-analysis showed no statistically significant differences between HBOT and the control group in terms of NIHSS score (MD = -1.41, 95%CI = -7.41 to 4.58), Barthel index (MD = 8.85, 95%CI = -5.84 to 23.54), TNF-α (MD = -5.78, 95%CI = -19.93 to 8.36), sICAM (MD = -308.47, 95%CI = -844.13 to 13227.19), sVCAM (MD = -122.84, 95%CI = -728.26 to 482.58), sE-selectin (MD = 0.11, 95%CI = -21.86 to 22.08), CRP (MD = -5.76, 95%CI = -15.02 to 3.51), adverse event incidence within ≤ 6 months of follow-up (OR = 0.98, 95%CI = 0.25 to 3.79). However, HBOT showed significant improvement in modified Rankin score (MD = 0.10, 95%CI = 0.03 to 0.17), and adverse event incidence at the end of treatment (OR = 0.42, 95%CI = 0.19 to 0.94) compared to the control group. CONCLUSION: While our findings do not support the routine use of HBOT for improving clinical outcomes in AIS, further research is needed to explore its potential efficacy within specific therapeutic windows and for different cerebral occlusion scenarios. Therefore, the possibility of HBOT offering clinical benefits for AIS cannot be entirely ruled out.


Assuntos
Oxigenoterapia Hiperbárica , AVC Isquêmico , Humanos , Oxigenoterapia Hiperbárica/efeitos adversos , AVC Isquêmico/etiologia
20.
BMC Infect Dis ; 24(1): 122, 2024 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-38262989

RESUMO

The Xpert MTB/RIF test (Xpert) can help in the accurate screening of tuberculosis, however, its widespread use is limited by its high cost and lack of accessibility. Pooling of sputum samples for testing is a strategy to cut expenses and enhance population coverage but may result in a decrease in detection sensitivity due to the dilution of Mycobacterium tuberculosis (Mtb) by sample mixing. We investigated how the mixing ratio affected the detection performance of Xpert. We used frozen sputum samples that had been kept after individual Xpert assays of the sputa from Mtb-confirmed TB patients and non-TB patients. Our results showed that the overall sensitivity of the Xpert pooling assay remained higher than 80% when the mixing ratio was between 1/2 and 1/8. When the mixing ratio was raised to 1/16, the positive detection rate fell to 69.0%. For patients with either a high sputum Mtb smear score ≥ 2+, a time-to-positive culture ≤ 10 days, or an Xpert test indicating a high or medium abundance of bacteria, the pooling assay positivity rates were 93.3%, 96.8%, and 100% respectively, even at a 1/16 mixing ratio. For participants with cavities and cough, the pooling assay positivity rates were 86.2% and 90.0% at a 1/8 ratio, higher than for those without these signs. Our results show that the Xpert pooled assay has a high overall sensitivity, especially for highly infectious patients. This pooling strategy with lower reagent and labor costs could support TB screening in communities with limited resources, thereby facilitating reductions in the community transmission and incidence of TB worldwide.


Assuntos
Mycobacterium tuberculosis , Tuberculose , Humanos , Escarro , Tosse , Bioensaio
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