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1.
Cell ; 187(13): 3319-3337.e18, 2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38810645

RESUMO

The development of perennial crops holds great promise for sustainable agriculture and food security. However, the evolution of the transition between perenniality and annuality is poorly understood. Here, using two Brassicaceae species, Crucihimalaya himalaica and Erysimum nevadense, as polycarpic perennial models, we reveal that the transition from polycarpic perennial to biennial and annual flowering behavior is a continuum determined by the dosage of three closely related MADS-box genes. Diversification of the expression patterns, functional strengths, and combinations of these genes endows species with the potential to adopt various life-history strategies. Remarkably, we find that a single gene among these three is sufficient to convert winter-annual or annual Brassicaceae plants into polycarpic perennial flowering plants. Our work delineates a genetic basis for the evolution of diverse life-history strategies in plants and lays the groundwork for the generation of diverse perennial Brassicaceae crops in the future.


Assuntos
Brassicaceae , Flores , Regulação da Expressão Gênica de Plantas , Brassicaceae/genética , Brassicaceae/fisiologia , Produtos Agrícolas/genética , Flores/genética , Flores/fisiologia , Proteínas de Domínio MADS/genética , Proteínas de Domínio MADS/metabolismo , Filogenia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Genoma de Planta , Fenômenos Fisiológicos Vegetais , Mapeamento Cromossômico , Mutação
2.
Proc Natl Acad Sci U S A ; 121(3): e2319335121, 2024 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-38198526

RESUMO

The phytohormone cytokinin has various roles in plant development, including meristem maintenance, vascular differentiation, leaf senescence, and regeneration. Prior investigations have revealed that cytokinin acts via a phosphorelay similar to the two-component system by which bacteria sense and respond to external stimuli. The eventual targets of this phosphorelay are type-B ARABIDOPSIS RESPONSE REGULATORS (B-ARRs), containing the conserved N-terminal receiver domain (RD), middle DNA binding domain (DBD), and C-terminal transactivation domain. While it has been established for two decades that the phosphoryl transfer from a specific histidyl residue in ARABIDOPSIS HIS PHOSPHOTRANSFER PROTEINS (AHPs) to an aspartyl residue in the RD of B-ARRs results in a rapid transcriptional response to cytokinin, the underlying molecular basis remains unclear. In this work, we determine the crystal structures of the RD-DBD of ARR1 (ARR1RD-DBD) as well as the ARR1DBD-DNA complex from Arabidopsis. Analyses of the ARR1DBD-DNA complex have revealed the structural basis for sequence-specific recognition of the GAT trinucleotide by ARR1. In particular, comparing the ARR1RD-DBD and ARR1DBD-DNA structures reveals that unphosphorylated ARR1RD-DBD exists in a closed conformation with extensive contacts between the RD and DBD. In vitro and vivo functional assays have further suggested that phosphorylation of the RD weakens its interaction with DBD, subsequently permits the DNA binding capacity of DBD, and promotes the transcriptional activity of ARR1. Our findings thus provide mechanistic insights into phosphorelay activation of gene transcription in response to cytokinin.


Assuntos
Arabidopsis , Citocininas , Ativação Transcricional , Arabidopsis/genética , Reguladores de Crescimento de Plantas , DNA
3.
Genome Res ; 33(9): 1582-1598, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37580131

RESUMO

Telomeres and subtelomeres, the genomic regions located at chromosome extremities, are essential for genome stability in eukaryotes. In the absence of the canonical maintenance mechanism provided by telomerase, telomere shortening induces genome instability. The landscape of the ensuing genome rearrangements is not accessible by short-read sequencing. Here, we leverage Oxford Nanopore Technologies long-read sequencing to survey the extensive repertoire of genome rearrangements in telomerase mutants of the model green microalga Chlamydomonas reinhardtii In telomerase-mutant strains grown for hundreds of generations, most chromosome extremities were capped by short telomere sequences that were either recruited de novo from other loci or maintained in a telomerase-independent manner. Other extremities did not end with telomeres but only with repeated subtelomeric sequences. The subtelomeric elements, including rDNA, were massively rearranged and involved in breakage-fusion-bridge cycles, translocations, recombinations, and chromosome circularization. These events were established progressively over time and displayed heterogeneity at the subpopulation level. New telomere-capped extremities composed of sequences originating from more internal genomic regions were associated with high DNA methylation, suggesting that de novo heterochromatin formation contributes to the restoration of chromosome end stability in C. reinhardtii The diversity of alternative strategies present in the same organism to maintain chromosome integrity and the variety of rearrangements found in telomerase mutants are remarkable, and illustrate genome plasticity at short timescales.


Assuntos
Chlamydomonas reinhardtii , Telomerase , Telomerase/genética , Telomerase/metabolismo , Chlamydomonas reinhardtii/genética , Chlamydomonas reinhardtii/metabolismo , Heterocromatina , Telômero/genética , Telômero/metabolismo , Translocação Genética , Instabilidade Cromossômica , Instabilidade Genômica
4.
Plant Cell ; 35(5): 1386-1407, 2023 04 20.
Artigo em Inglês | MEDLINE | ID: mdl-36748203

RESUMO

Plants undergo extended morphogenesis. The shoot apical meristem (SAM) allows for reiterative development and the formation of new structures throughout the life of the plant. Intriguingly, the SAM produces morphologically different leaves in an age-dependent manner, a phenomenon known as heteroblasty. In Arabidopsis thaliana, the SAM produces small orbicular leaves in the juvenile phase, but gives rise to large elliptical leaves in the adult phase. Previous studies have established that a developmental decline of microRNA156 (miR156) is necessary and sufficient to trigger this leaf shape switch, although the underlying mechanism is poorly understood. Here we show that the gradual increase in miR156-targeted SQUAMOSA PROMOTER BINDING PROTEIN-LIKE transcription factors with age promotes cell growth anisotropy in the abaxial epidermis at the base of the leaf blade, evident by the formation of elongated giant cells. Time-lapse imaging and developmental genetics further revealed that the establishment of adult leaf shape is tightly associated with the longitudinal cell expansion of giant cells, accompanied by a prolonged cell proliferation phase in their vicinity. Our results thus provide a plausible cellular mechanism for heteroblasty in Arabidopsis, and contribute to our understanding of anisotropic growth in plants.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , MicroRNAs , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Fatores de Transcrição/metabolismo , Folhas de Planta/metabolismo , Meristema/genética , Meristema/metabolismo , Proliferação de Células/genética , Regulação da Expressão Gênica de Plantas/genética , MicroRNAs/genética , MicroRNAs/metabolismo
5.
Genes Dev ; 32(23-24): 1499-1513, 2018 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-30463903

RESUMO

In cells lacking telomerase, telomeres gradually shorten during each cell division to reach a critically short length, permanently activate the DNA damage checkpoint, and trigger replicative senescence. The increase in genome instability that occurs as a consequence may contribute to the early steps of tumorigenesis. However, because of the low frequency of mutations and the heterogeneity of telomere-induced senescence, the timing and mechanisms of genome instability increase remain elusive. Here, to capture early mutation events during replicative senescence, we used a combined microfluidic-based approach and live-cell imaging in yeast. We analyzed DNA damage checkpoint activation in consecutive cell divisions of individual cell lineages in telomerase-negative yeast cells and observed that prolonged checkpoint arrests occurred frequently in telomerase-negative lineages. Cells relied on the adaptation to the DNA damage pathway to bypass the prolonged checkpoint arrests, allowing further cell divisions despite the presence of unrepaired DNA damage. We demonstrate that the adaptation pathway is a major contributor to the genome instability induced during replicative senescence. Therefore, adaptation plays a critical role in shaping the dynamics of genome instability during replicative senescence.


Assuntos
Adaptação Fisiológica/genética , Pontos de Checagem do Ciclo Celular/genética , Dano ao DNA/genética , Instabilidade Genômica/genética , Saccharomyces cerevisiae/genética , Reparo do DNA , Genoma Fúngico/genética , Técnicas Analíticas Microfluídicas , Mutação , Imagem Óptica , Saccharomyces cerevisiae/enzimologia , Telomerase/genética
6.
J Am Chem Soc ; 146(31): 21389-21400, 2024 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-38875215

RESUMO

We present an efficient one-pot photochemical skeletal editing protocol for the transformation of pyridines into diverse bicyclic pyrazolines and pyrazoles under mild conditions. The method requires no metals, photocatalysts, or additives and allows for the selective removal of specific carbon atoms from pyridines, allowing for unprecedented versatility. Our approach offers a convenient and efficient means for the late-stage modification of complex drug molecules by replacing the core pyridine skeleton. Moreover, we have successfully scaled up this procedure in stop-flow and flow-chemistry systems, showcasing its applicability to intricate transformations such as the Diels-Alder reaction, hydrogenation, [3 + 2] cycloaddition, and Heck reaction. Through control experiments and DFT calculations, we provide insights into the mechanistic underpinnings of this skeletal editing protocol.

7.
Anal Chem ; 96(37): 14853-14859, 2024 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-39213638

RESUMO

The etiology and pathological complexity of acute kidney injury (AKI) pose great challenges for early diagnosis, typing, and personalized treatment. It is an important reason for poor prognosis and high mortality of AKI. In order to provide a relatively noninvasive diagnostic and typing method for AKI, we proposed the pathological changes of albumin permeability after glomerular injury and reabsorption efficiency after tubular injury as potential entry points. Thus, a renal tubule labeling fluorescent dye which features albumin concentration-related fluorescence intensity was used to fit these pathological changes. Utilizing this fluorescence assay, we realized urinary tract obstruction imaging as early as 12 h after morbidity. For glomerular and tubular injury discrimination, compared to a healthy control, membranous nephropathy as a representative glomerular injury resulted in enhanced fluorescence intensity of the kidney due to increased albumin penetration, while renal tubular injury caused insufficient dye reabsorption to exhibit weakened fluorescence intensity. The significant differences demonstrated the feasibility of this approach for fluorescence imaging-based AKI typing in vivo.


Assuntos
Injúria Renal Aguda , Corantes Fluorescentes , Glomérulos Renais , Túbulos Renais , Animais , Túbulos Renais/patologia , Túbulos Renais/lesões , Túbulos Renais/metabolismo , Injúria Renal Aguda/diagnóstico , Injúria Renal Aguda/patologia , Injúria Renal Aguda/metabolismo , Corantes Fluorescentes/química , Glomérulos Renais/patologia , Glomérulos Renais/metabolismo , Glomérulos Renais/lesões , Fluorometria/métodos , Camundongos , Imagem Óptica , Humanos , Masculino
8.
Anal Chem ; 2024 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-39305236

RESUMO

The traditional magnetic relaxation switching (MRS) sensors have excellent sensitivity, but their stability is poor because the magnetic relaxation signal is easily affected by the external magnetic field or environmental oxidation. In this study, a highly stable hydrogel bead-based MRS (Gel-MRS) sensor was established for the accurate and sensitive detection of Cd2+ in rice. A pH-responsive hydrogel bead was applied as a core element for the target stimulus and transverse relaxation signal transduction. The stability experiments showed that the transverse relaxation time (T2) change of the Gel-MRS sensor was one-seventh that of traditional magnetic nanoparticles under an external magnetic field and less than a fifth that of Fe2+/Fe3+ conversion in air. The excellent stability was due to the fact that T2 of the Gel-MRS sensor came from the swelling system mediated by pH rather than the traditional aggregation/dispersion or Fe2+/Fe3+ conversion of magnetic nanoparticles. In addition, the target Cd2+ could exclusively trigger a pH response of the hydrogel beads, altering the T2, thus resulting in excellent relaxation properties (R2 = 56.89) and pH responsiveness of the Gel-MRS sensor. The swelling process of the hydrogel beads followed quasi-second-order dynamics. The Gel-MRS sensor demonstrated a remarkable limit of detection as low as 0.009 ng/mL for Cd2+, with a linear range of 0.01-5 ng/mL. The excellent stability and sensitivity made the Gel-MRS sensor have great application potential in food and environmental detection.

9.
Small ; : e2402762, 2024 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-39194587

RESUMO

Bimetallic atom catalysts exhibit ultra-high oxygen electrocatalytic activity by harnessing mutual promotion and synergistic effects between adjacent metal active centers, surpassing the performance of single metal atomic catalysts. Herein, FeNi atom pairs protected by hierarchical porous annular carbon grids (P-FeNi-NPC) are introduced using a mediator-assisted MOFs-derived strategy. The introduction of the multi-block copolymer P123 ensures the uniform confinement and dispersion of metal ions, followed by thermal decomposition to form a "planetary-ring-like" carbon framework that anchors the bimetallic atomic pairs in the active region. The homogeneous distribution of adjacent Fe-N4 and Ni-N4 active sites significantly enhances catalytic activity and stability. Leveraging unique electronic and geometric structures, the resulting P-FeNi-NPC catalyst demonstrates exceptional ORR and OER activities with an ΔE value of 0.705 (E1/2 = 0.845 V, Ej = 10 = 1.55 V). Theoretical calculations unveil that FeNi bimetallic sites loaded on nitrogen-doped carbon frameworks with specific curvature effectively modulate the energy of d-band centers, thus balancing the free energy of oxygen-containing intermediates. This study presents a novel and versatile approach for synthesizing advanced bifunctional catalysts, poised to drive the future development of Zn-air batteries.

10.
J Transl Med ; 22(1): 489, 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38778315

RESUMO

OBJECTIVE: Mild therapeutic hypothermia (MTH) is an important method for perioperative prevention and treatment of myocardial ischemia-reperfusion injury (MIRI). Modifying mitochondrial proteins after protein translation to regulate mitochondrial function is one of the mechanisms for improving myocardial ischemia-reperfusion injury. This study investigated the relationship between shallow hypothermia treatment improving myocardial ischemia-reperfusion injury and the O-GlcNAcylation level of COX10. METHODS: We used in vivo Langendorff model and in vitro hypoxia/reoxygenation (H/R) cell model to investigate the effects of MTH on myocardial ischemia-reperfusion injury. Histological changes, myocardial enzymes, oxidative stress, and mitochondrial structure/function were assessed. Mechanistic studies involved various molecular biology methods such as ELISA, immunoprecipitation (IP), WB, and immunofluorescence. RESULTS: Our research results indicate that MTH upregulates the O-GlcNACylation level of COX10, improves mitochondrial function, and inhibits the expression of ROS to improve myocardial ischemia-reperfusion injury. In vivo, MTH effectively alleviates ischemia-reperfusion induced cardiac dysfunction, myocardial injury, mitochondrial damage, and redox imbalance. In vitro, the OGT inhibitor ALX inhibits the OGT mediated O-GlcNA acylation signaling pathway, downregulates the O-Glc acylation level of COX10, promotes ROS release, and counteracts the protective effect of MTH. On the contrary, the OGA inhibitor ThG showed opposite effects to ALX, further confirming that MTH activated the OGT mediated O-GlcNAcylation signaling pathway to exert cardioprotective effects. CONCLUSIONS: In summary, MTH activates OGT mediated O-glycosylation modified COX10 to regulate mitochondrial function and improve myocardial ischemia-reperfusion injury, which provides important theoretical basis for the clinical application of MTH.


Assuntos
Hipotermia Induzida , Traumatismo por Reperfusão Miocárdica , Regulação para Cima , Animais , Traumatismo por Reperfusão Miocárdica/patologia , Traumatismo por Reperfusão Miocárdica/metabolismo , Masculino , Estresse Oxidativo , Espécies Reativas de Oxigênio/metabolismo , Ratos Sprague-Dawley , Mitocôndrias Cardíacas/metabolismo , Mitocôndrias Cardíacas/patologia , Mitocôndrias/metabolismo , Glicosilação , Acilação
11.
Hepatology ; 78(2): 547-561, 2023 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-35839302

RESUMO

BACKGROUND AND AIMS: Nonalcoholic fatty liver disease (NAFLD), a complex metabolic syndrome, has limited therapeutic options. Microsomal prostaglandin E synthase-2 (mPGES-2) was originally discovered as a prostaglandin E 2 (PGE 2 ) synthase; however, it does not produce PGE 2 in the liver. Moreover, the role of mPGES-2 in NAFLD remains undefined. Herein, we aimed to determine the function and mechanism of mPGES-2 in liver steatosis and steatohepatitis. APPROACH AND RESULTS: To evaluate the role of mPGES-2 in NAFLD, whole-body or hepatocyte-specific mPGES-2-deficient mice fed a high-fat or methionine-choline-deficient diet were used. Compared with control mice, mPGES-2-deficient mice showed reduced hepatic lipid accumulation, along with ameliorated liver injury, inflammation, and fibrosis. Furthermore, the protective effect of mPGES-2 deficiency against NAFLD was dependent on decreased cytochrome P450 4A14 and increased acyl-CoA thioesterase 4 levels regulated by the heme receptor nuclear receptor subfamily 1 group D member 1 (NR1D1), but not PGE 2 . Heme regulated the increased NR1D1 activity mediated by mPGES-2 deficiency. Further, we confirmed the protective role of the mPGES-2 inhibitor SZ0232 in NAFLD therapy. CONCLUSION: Our study indicates the pathogenic role of mPGES-2 and outlines the mechanism in mediating NAFLD, thereby highlighting the therapeutic potential of mPGES-2 inhibition in liver steatosis and steatohepatitis.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Camundongos , Animais , Hepatopatia Gordurosa não Alcoólica/patologia , Prostaglandina-E Sintases/metabolismo , Heme , Modelos Animais de Doenças , Fígado/patologia , Camundongos Endogâmicos C57BL
12.
Opt Lett ; 49(13): 3765-3768, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38950262

RESUMO

AlGaInP-based red light emitting diodes (LEDs) are considered as promising light sources in future full-color displays. At present, vertical chip configuration is still the mainstream device structure of AlGaInP-based red LEDs. However, current crowding around p-electrode severely hinders an efficient improvement. Here, we propose a Schottky-contact current blocking layer (SCBL) to enhance current spreading and to improve light extraction efficiency of AlGaInP-based red vertical miniaturized LEDs (mini-LEDs). By utilizing the Schottky contact between ITO and p-GaP, the SCBL can hinder current crowding around the p-electrode. The current is forced to inject into an active region through a p-GaP+ ohmic contact layer, avoiding light absorption by p-electrode. Through the transfer length method, the Schottky contact characteristics between the ITO and p-GaP as well as the ohmic contact characteristics between ITO and p-GaP+ are demonstrated. Benefiting from superior current spreading and improved light extraction, a mini-LED with SCBL realizes an enhancement of 31.8% in external quantum efficiency (EQE) at 20 mA in comparison with a mini-LED without SCBL.

13.
Opt Lett ; 49(6): 1449-1452, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38489422

RESUMO

AlGaInP-based light-emitting diodes (LEDs) suffer from a low external quantum efficiency (EQE), which is mainly restrained by the poor light extraction efficiency. Here, we demonstrate AlGaInP-based vertical miniaturized-LEDs (mini-LEDs) with a porous n-AlGaInP surface using a wet etching process to boost light extraction. We investigated the effects of etching time on the surface morphology of the porous n-AlGaInP surface. We found that as the etching time is prolonged, the density of pores increases initially and decreases subsequently. In comparison with the vertical mini-LED with a smooth n-AlGaInP surface, the vertical mini-LEDs with the porous n-AlGaInP surface reveal improvement in light output power and EQE, meanwhile, without the deterioration of electrical performance. The highest improvement of 38.9% in EQE measured at 20 mA is observed from the vertical mini-LED with the maximum density of the pores. Utilizing a three-dimensional finite-difference time-domain method, we reveal the underlying mechanisms of improved performance, which are associated with suppressed total internal reflection and efficient light scattering effect of the pores.

14.
Respir Res ; 25(1): 270, 2024 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-38987833

RESUMO

BACKGROUND: Hypoxic pulmonary hypertension (HPH) is a challenging lung arterial disorder with remarkably high incidence and mortality rates, and the efficiency of current HPH treatment strategies is unsatisfactory. Endothelial-to-mesenchymal transition (EndMT) in the pulmonary artery plays a crucial role in HPH. Previous studies have shown that lncRNA-H19 (H19) is involved in many cardiovascular diseases by regulating cell proliferation and differentiation but the role of H19 in EndMT in HPH has not been defined. METHODS: In this research, the expression of H19 was investigated in PAH human patients and rat models. Then, we established a hypoxia-induced HPH rat model to evaluate H19 function in HPH by Echocardiography and hemodynamic measurements. Moreover, luciferase reporter gene detection, and western blotting were used to explore the mechanism of H19. RESULTS: Here, we first found that the expression of H19 was significantly increased in the endodermis of pulmonary arteries and that H19 deficiency obviously ameliorated pulmonary vascular remodelling and right heart failure in HPH rats, and these effects were associated with inhibition of EndMT. Moreover, an analysis of luciferase activity indicated that microRNA-let-7 g (let-7 g) was a direct target of H19. H19 deficiency or let-7 g overexpression can markedly downregulate the expression of TGFßR1, a novel target gene of let-7 g. Furthermore, inhibition of TGFßR1 induced similar effects to H19 deficiency. CONCLUSIONS: In summary, our findings demonstrate that the H19/let-7 g/TGFßR1 axis is crucial in the pathogenesis of HPH by stimulating EndMT. Our study may provide new ideas for further research on HPH therapy in the near future.


Assuntos
Transição Epitelial-Mesenquimal , Hipertensão Pulmonar , MicroRNAs , RNA Endógeno Competitivo , RNA Longo não Codificante , Transdução de Sinais , Fator de Crescimento Transformador beta , Animais , Feminino , Humanos , Masculino , Ratos , Modelos Animais de Doenças , Transição Epitelial-Mesenquimal/fisiologia , Transição Epitelial-Mesenquimal/genética , Hipertensão Pulmonar/metabolismo , Hipertensão Pulmonar/genética , Hipertensão Pulmonar/patologia , Hipóxia/metabolismo , Hipóxia/genética , MicroRNAs/metabolismo , MicroRNAs/genética , Artéria Pulmonar/metabolismo , Artéria Pulmonar/patologia , Ratos Sprague-Dawley , Receptor do Fator de Crescimento Transformador beta Tipo I/metabolismo , Receptor do Fator de Crescimento Transformador beta Tipo I/genética , RNA Endógeno Competitivo/genética , RNA Endógeno Competitivo/metabolismo , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Transdução de Sinais/fisiologia , Fator de Crescimento Transformador beta/metabolismo
15.
Chemistry ; 30(54): e202401830, 2024 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-39037552

RESUMO

The catalytic direct hydroarylation of alkynamides is a highly efficient approach for accessing functionalized trisubstituted arylalkenes with amide groups. Herein, we report a rhodium-catalyzed pyridylation of alkynamides with pyridylboronic acids, producing a variety of primary, secondary, and tertiary enamides with high yields (up to 94 %). This reaction demonstrates broad tolerance towards various alkyl and aryl functional groups, providing convenient access to a diverse array of alkenylpyridine derivatives. To demonstrate potential applications in late-stage hydropyridylation, we synthesized α,ß-unsaturated ketones, aldehydes, and esters with high yields from the pyridylation product of Weinreb amides. This indirect expansion of the substrate scope enhances the practicality of this strategy. Additionally, the α,ß-unsaturated ketone obtained can be further reduced to yield a chiral alcohol with a 99 % ee, further demonstrating the versatility and potential utility of this approach.

16.
BMC Infect Dis ; 24(1): 920, 2024 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-39232674

RESUMO

BACKGROUND: Sepsis remains a leading cause of mortality in intensive care units, and rapid and accurate pathogen detection is crucial for effective treatment. This study evaluated the clinical application of multi-site metagenomic next-generation sequencing (mNGS) for the diagnosis of sepsis, comparing its performance against conventional methods. METHODS: A retrospective analysis was conducted on 69 patients with sepsis consecutively admitted to the Department of Intensive Care Medicine, Meizhou People's Hospital. Samples of peripheral blood and infection sites were collected for mNGS and conventional method tests to compare the positive rate of mNGS and traditional pathogen detection methods and the distribution of pathogens. The methods used in this study included a comprehensive analysis of pathogen consistency between peripheral blood and infection site samples. Additionally, the correlation between the pathogens detected and clinical outcomes was investigated. RESULTS: Of the patients with sepsis, 57.97% experienced dyspnea, and 65.2% had underlying diseases, with hypertension being the most common. mNGS demonstrated a significantly higher pathogen detection rate (88%) compared to the conventional method tests (26%). The pathogen consistency rate was 60% between plasma and bronchoalveolar lavage fluid samples, and that of plasma and local body fluid samples was 63%. The most frequently detected pathogens were gram-negative bacteria, and Klebsiella pneumonia. There were no significant differences in the clinical features between the pathogens. CONCLUSION: mNGS is significantly superior to conventional methods in pathogen detection. There was a notable high pathogen consistency detection between blood and local body fluid samples, supporting the clinical relevance of mNGS. This study highlights the superiority of mNGS in detecting a broad spectrum of pathogens quickly and accurately. TRIAL REGISTRATION: Not applicable.


Assuntos
Sequenciamento de Nucleotídeos em Larga Escala , Unidades de Terapia Intensiva , Metagenômica , Sepse , Humanos , Sepse/diagnóstico , Sepse/microbiologia , Masculino , Feminino , Pessoa de Meia-Idade , Estudos Retrospectivos , Idoso , Metagenômica/métodos , Adulto , Bactérias/isolamento & purificação , Bactérias/genética , Bactérias/classificação , Idoso de 80 Anos ou mais
17.
BMC Pregnancy Childbirth ; 24(1): 616, 2024 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-39342136

RESUMO

BACKGROUND: Maternal lipid metabolism has been implicated in elevating the risk of adverse pregnancy outcomes, which is a particularly significant concern in twin pregnancies. However, the precise relationship between early pregnancy dyslipidemia and the risk of preterm birth (PTB) in twin pregnancies remains unclear. METHODS: This retrospective cohort study included women with twin pregnancies between January 2018 and December 2023. Early pregnancy blood lipid profiles, including total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), triglyceride (TG) and high-density lipoprotein cholesterol (HDL-C), were examined. Dyslipidemia was diagnosed based on the diagnostic criteria outlined in the 2016 guidelines for the prevention and treatment of dyslipidemia in Chinese adults. PTB was defined as birth occurring before 37 weeks of pregnancy. Logistic regression models were used to evaluate the association of early pregnancy dyslipidemia with PTB in twin pregnancies. RESULTS: A total of 613 women with twin pregnancies were included, and 141 women were complicated with dyslipidemia. The incidence of PTB < 37 weeks was significantly higher in the dyslipidemia group compared to the group without dyslipidemia (64.5% vs. 50.4%, P = 0.003). After adjusting for confounding factors, dyslipidemia was positively associated with PTB < 37 weeks (adjusted odds ratio: 1.71; 95% confidence interval: 1.13-2.58). However, these associations varied depending on the chorionicity and mode of conception of the twins. The positive associations between early pregnancy dyslipidemia and PTB < 37 weeks remained significant only in spontaneously conceived (SC) or dichorionic diamniotic (DCDA) twin pregnancies. No statistically significant associations were observed between dyslipidemia and the other secondary outcomes. CONCLUSION: Early pregnancy dyslipidemia was positively associated with PTB < 37 weeks in twin pregnancies, and this association remained significant in SC or DCDA twin pregnancies. Comprehensive lipid profile assessment in the first trimester may be beneficial for patients' monitoring and implementing interventions to mitigate adverse pregnancy outcomes.


Assuntos
Dislipidemias , Gravidez de Gêmeos , Nascimento Prematuro , Humanos , Feminino , Gravidez , Dislipidemias/epidemiologia , Dislipidemias/sangue , Estudos Retrospectivos , Gravidez de Gêmeos/sangue , Adulto , Nascimento Prematuro/epidemiologia , Nascimento Prematuro/etiologia , Nascimento Prematuro/sangue , Complicações na Gravidez/sangue , Complicações na Gravidez/epidemiologia , China/epidemiologia , Fatores de Risco , Triglicerídeos/sangue , Estudos de Coortes
18.
Proc Natl Acad Sci U S A ; 118(46)2021 11 16.
Artigo em Inglês | MEDLINE | ID: mdl-34750273

RESUMO

What determines the rate at which a multicellular organism matures is a fundamental question in biology. In plants, the decline of miR156 with age serves as an intrinsic, evolutionarily conserved timer for the juvenile-to-adult phase transition. However, the way in which age regulates miR156 abundance is poorly understood. Here, we show that the rate of decline in miR156 is correlated with developmental age rather than chronological age. Mechanistically, we found that cell division in the apical meristem is a trigger for miR156 decline. The transcriptional activity of MIR156 genes is gradually attenuated by the deposition of the repressive histone mark H3K27me3 along with cell division. Our findings thus provide a plausible explanation of why the maturation program of a multicellular organism is unidirectional and irreversible under normal growth conditions and suggest that cell quiescence is the fountain of youth in plants.


Assuntos
Proteínas de Arabidopsis/genética , Arabidopsis/genética , Divisão Celular/genética , Meristema/genética , MicroRNAs/genética , Brotos de Planta/genética , Regulação da Expressão Gênica no Desenvolvimento/genética , Regulação da Expressão Gênica de Plantas/genética , Folhas de Planta/genética , Plantas Geneticamente Modificadas/genética , Fatores de Transcrição/genética
19.
J Clin Ultrasound ; 52(2): 208-218, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38108620

RESUMO

PURPOSE: Using visible human, MRI and ultrasound images, we aim to provide an anatomical basis for the identification and diagnosis of pelvic floor structure and disease by ultrasound imaging. METHODS: One Chinese visible human (CVH) image, one American visible human image, 9 MRI images of normal volunteers, and 40 ultrasound images of normal volunteers or pelvic organ prolapse patients were used. Pelvic organs, pelvic floor muscles, and the connective tissue in CVH, VHP, MRI, and ultrasound images were selected for comparative study. RESULTS: We successfully identified the boundary of the anal sphincter complex, including the subcutaneous, superficial, and deep parts of the external anal sphincter, conjoined longitudinal muscles and internal anal sphincter; the levator ani muscle (LAM), including the internal and external parts of the pubovisceral muscle and the superficial and deep parts of the puborectal muscle; the urethral sphincter complex, including the urethral sphincter proper and the urethral compressor; and the perineal body, the rectoperineal muscle and superficial transverse perineal muscle. CONCLUSIONS: We successfully recognized and studied the location, subdivisions, 2D morphology and spatial relationships of the LAM, anal sphincter complex, urethral sphincter complex and perineal body in ultrasound images, thereby helping sonologists or clinicians accurately identify pelvic floor muscles and supporting structures in ultrasound images.


Assuntos
Canal Anal , Diafragma da Pelve , Humanos , Feminino , Diafragma da Pelve/diagnóstico por imagem , Diafragma da Pelve/anatomia & histologia , Diafragma da Pelve/fisiologia , Canal Anal/diagnóstico por imagem , Músculo Esquelético , Ultrassonografia , Imageamento por Ressonância Magnética
20.
Molecules ; 29(17)2024 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-39275067

RESUMO

Chinese Olea europaea leaves, rich in verbascosides, were extracted using ultrasound-assisted extraction (UAE) and wall-breaking extraction (WBE) with deep eutectic solvents (Optimal UAE: 55 min, 200 mL/g liquid-solid ratio, 20% moisture, yielding 206.23 ± 0.58 mg GAE/g total phenolic content (TPC) and 1.59 ± 0.04% verbascoside yield (VAY); Optimal WBE: 140 s, 210 mL/g, 30% moisture, giving 210.69 ± 0.97 mg GAE/g TPC and 1.33 ± 0.2% VAY). HPLC analysis showed that young leaves accumulated higher TPC and phenolic compounds. Among the five olive varieties, Koroneiki and Chemlal showed the highest TPC in UAE, while Arbosana and Chemlal excelled in WBE. WBE yielded a higher TPC and rutin, whereas UAE marginally increased other phenolics. Additionally, the DPPH• assay showed that WBE-extracted verbascoside-rich extracts (VREs) of Chemlal exhibited high antioxidant activity (EC50 of 57 mg/mL), but Koroneiki-VREs exhibited lower activity against the ABTS•+ radical (EC50 of 134 mg/mL). Remarkably, the UAE/WBE-extracted Chemlal-VREs promoted the normal esophageal Het-1A cell line at 25 µg/mL for 24 h; yet, the esophageal cancer Eca-109 cells were sensibly inhibited, especially at 50 µg/mL; and the cell viability decreased dramatically. The results confirmed WBE as a relatively efficient method, and the Chemlal variety may be an excellent source of verbascoside.


Assuntos
Antioxidantes , Glucosídeos , Olea , Fenóis , Extratos Vegetais , Folhas de Planta , Solventes , Humanos , Antineoplásicos Fitogênicos/farmacologia , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Antioxidantes/farmacologia , Antioxidantes/química , Antioxidantes/isolamento & purificação , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Cromatografia Líquida de Alta Pressão , Glucosídeos/isolamento & purificação , Glucosídeos/química , Glucosídeos/farmacologia , Olea/química , Fenóis/química , Fenóis/isolamento & purificação , Fenóis/farmacologia , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Folhas de Planta/química , Polifenóis , Solventes/química
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