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1.
Plant Cell ; 35(8): 2910-2928, 2023 08 02.
Artículo en Inglés | MEDLINE | ID: mdl-37195876

RESUMEN

The regulation of microRNA (miRNA) biogenesis is crucial for maintaining plant homeostasis under biotic and abiotic stress. The crosstalk between the RNA polymerase II (Pol-II) complex and the miRNA processing machinery has emerged as a central hub modulating transcription and cotranscriptional processing of primary miRNA transcripts (pri-miRNAs). However, it remains unclear how miRNA-specific transcriptional regulators recognize MIRNA loci. Here, we show that the Arabidopsis (Arabidopsis thaliana) HIGH EXPRESSION OF OSMOTICALLY RESPONSIVE GENE15 (HOS15)-HISTONE DEACETYLASE9 (HDA9) complex is a conditional suppressor of miRNA biogenesis, particularly in response to abscisic acid (ABA). When treated with ABA, hos15/hda9 mutants show enhanced transcription of pri-miRNAs that is accompanied by increased processing, leading to overaccumulation of a set of mature miRNAs. Moreover, upon recognition of the nascent pri-miRNAs, the ABA-induced recruitment of the HOS15-HDA9 complex to MIRNA loci is guided by HYPONASTIC LEAVES 1 (HYL1). The HYL1-dependent recruitment of the HOS15-HDA9 complex to MIRNA loci suppresses expression of MIRNAs and processing of pri-miRNA. Most importantly, our findings indicate that nascent pri-miRNAs serve as scaffolds for recruiting transcriptional regulators, specifically to MIRNA loci. This indicates that RNA molecules can act as regulators of their own expression by causing a negative feedback loop that turns off their transcription, providing a self-buffering system.


Asunto(s)
Proteínas de Arabidopsis , Arabidopsis , MicroARNs , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Histonas/metabolismo , Ácido Abscísico/farmacología , Ácido Abscísico/metabolismo , Proteínas de Unión al ARN/metabolismo , Arabidopsis/genética , Arabidopsis/metabolismo , MicroARNs/genética , MicroARNs/metabolismo , Procesamiento Postranscripcional del ARN , Regulación de la Expresión Génica de las Plantas , Histona Desacetilasas/genética , Histona Desacetilasas/metabolismo
2.
J Exp Bot ; 75(8): 2481-2493, 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38280208

RESUMEN

The plant hormone abscisic acid (ABA) is an important regulator of plant growth and development and plays a crucial role in both biotic and abiotic stress responses. ABA modulates flowering time, but the precise molecular mechanism remains poorly understood. Here we report that ABA INSENSITIVE 2 (ABI2) is the only phosphatase from the ABA-signaling core that positively regulates the transition to flowering in Arabidopsis. Loss-of-function abi2-2 mutant shows significantly delayed flowering both under long day and short day conditions. Expression of floral repressor genes such as FLOWERING LOCUS C (FLC) and CYCLING DOF FACTOR 1 (CDF1) was significantly up-regulated in abi2-2 plants while expression of the flowering promoting genes FLOWERING LOCUS T (FT) and SUPPRESSOR OF OVEREXPRESSION OF CONSTANS 1 (SOC1) was down-regulated. Through genetic interactions we further found that ost1-3 and abi5-1 mutations are epistatic to abi2-2, as both of them individually rescued the late flowering phenotype of abi2-2. Interestingly, phosphorylation and protein stability of ABA INSENSITIVE 5 (ABI5) were enhanced in abi2-2 plants suggesting that ABI2 dephosphorylates ABI5, thereby reducing protein stability and the capacity to induce FLC expression. Our findings uncovered the unexpected role of ABI2 in promoting flowering by inhibiting ABI5-mediated FLC expression in Arabidopsis.


Asunto(s)
Proteínas de Arabidopsis , Arabidopsis , Ácido Abscísico/metabolismo , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Factores de Transcripción con Cremalleras de Leucina de Carácter Básico/metabolismo , Regulación de la Expresión Génica de las Plantas , Fosforilación , Reguladores del Crecimiento de las Plantas/metabolismo , Proteínas Quinasas/metabolismo
3.
Opt Lett ; 49(3): 522-525, 2024 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-38300049

RESUMEN

Spatial light modulators (SLMs) have become an indispensable element in modern optics for their versatile performance in many applications. Among various types of SLMs, such as digital micromirror devices (DMD), liquid crystal-based phase-only spatial light modulators (LC-SLMs), and deformable mirrors (DM), LC-SLMs are often the method of choice due to their high efficiency, precise phase modulation, and abundant number of effective pixels. In general, for research grade applications, an additional SLM calibration step is required due to fabrication imperfection resulting in non-flat liquid crystal panels and varying phase responses over the SLM area. Here, we demonstrate a straightforward approach for reference-free orthogonal calibration of an arbitrary number of SLM subregions which only requires the same measurement time as global calibration. The proposed method requires minimal optical elements and can be applied to any optical setup as is. As a benchmark performance test, we achieved a 2.2-fold enhancement in correction efficiency for wavefront shaping through scattering media utilizing the calibrated 2160 subregions of the SLM, in comparison with a single global look-up table (LUT).

4.
Gastrointest Endosc ; 100(3): 557-566.e10, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38583543

RESUMEN

BACKGROUND AND AIMS: Endobiliary radiofrequency ablation (RFA) is an emerging endoscopic palliative adjunctive therapy used for the local treatment of unresectable malignant biliary obstruction (MBO). However, irregular ablation ranges caused by insufficient electrode-to-bile duct contact pose a significant obstacle. We investigated the feasibility of a self-expandable stent (SES)-based electrode with a customized RFA generator in the porcine liver and common bile duct (CBD). METHODS: An SES-RFA system with polarity switching was developed to perform endobiliary RFA. The ablation ranges of 20 ablation protocols were evaluated to validate the feasibility of the newly developed RFA system in the porcine liver. Nine of 20 ablation protocols were selected for evaluation in the porcine CBD with cholangiography, endoscopy, and histologic and immunohistochemical analysis. RESULTS: The SES-RFA system with polarity switching was successfully constructed and demonstrated high accuracy and reproducibility. The ablation area was clearly identified between the 2 SESs. The ablation ranges and degree of mucosal damage, including terminal deoxynucleotidyl transferase-mediated dUTP nick and labeling-positive and heat shock protein 70-positive depositions, increased proportionally with ablation protocols in the porcine liver and CBD (all P < .05). Ablation length and depth linearly increased with ablation protocols from 8.74 ± .25 to 31.25 ± .67 mm and 1.61 ± .09 to 11.94 ± .44 mm, respectively. CONCLUSIONS: The SES-RFA system with polarity switching between electrodes provided an even circumferential area of ablation and enhanced ablation depth between the electrodes. This novel endobiliary RFA system is a promising modality for local ablation in patients with unresectable MBO.


Asunto(s)
Colestasis , Ablación por Radiofrecuencia , Animales , Porcinos , Colestasis/cirugía , Colestasis/etiología , Ablación por Radiofrecuencia/métodos , Stents , Conducto Colédoco/cirugía , Hígado/cirugía , Hígado/patología , Estudios de Factibilidad , Colangiografía , Stents Metálicos Autoexpandibles
5.
Soft Matter ; 20(36): 7313-7320, 2024 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-39248026

RESUMEN

In nature, bacteria often swim in complex fluids, but our understanding of the interactions between bacteria and complex surroundings is still evolving. In this work, rod-like Bacillus subtilis swims in a quasi-2D environment with aqueous liquid-liquid interfaces, i.e., the isotropic-nematic coexistence phase of an aqueous chromonic liquid crystal. Focusing on the bacteria motion near and at the liquid-liquid interfaces, we collect and quantify bacterial trajectories ranging across the isotropic to the nematic phase. Despite its small magnitude, the interfacial tension of the order of 10 µN m-1 at the isotropic-nematic interface justifies our observations that bacteria swimming more perpendicular to the interface have a higher probability of crossing the interface. Our force-balance model, considering the interfacial tension, further predicts how the length and speed of the bacteria affect their crossing behaviors. Investigating how a phase change affects bacterial motion, we also find, as soon as the bacteria cross the interface and enter the nematic phase, they wiggle less, but faster, and that this occurs as the flagellar bundles aggregate within the nematic phase. Given the ubiquity of multi-phases in biological environments, our findings will help to understand active transport across various phases.


Asunto(s)
Bacillus subtilis , Agua/química , Cristales Líquidos/química , Movimiento , Tensión Superficial
6.
BMC Gastroenterol ; 24(1): 14, 2024 Jan 03.
Artículo en Inglés | MEDLINE | ID: mdl-38172745

RESUMEN

PURPOSE: To explore the value of clinical application with the whole process computed tomography (CT) guided percutaneous gastrostomy in esophageal tumor patients. MATERIALS AND METHODS: A consecutive series of 32 esophageal tumor patients in whom endoscopic gastrostomy or fluoroscopy guided gastrostomy were considered too dangerous or impossible due to the esophagus complete obstruction, complicate esophageal mediastinal fistula, esophageal trachea fistula or severe heart disease. All of the 32 patients were included in this study from 2 medical center and underwent the gastrostomy under whole process CT guided. RESULTS: All of the gastrostomy procedure was finished successfully under whole process CT guided and the technical success rate was 100%. The average time for each operation was 27 min. No serious complications occurred and the minor complications occurred in 3 patients, including local infection, severe hyperplasia of granulation tissue and tube dislodgment. There were no procedure related deaths. CONCLUSION: The technical success rate of whole process CT guided percutaneous gastrostomy is high and the complication is low. This technique can be used feasible and effectively in some special patients.


Asunto(s)
Neoplasias Esofágicas , Gastrostomía , Humanos , Gastrostomía/métodos , Endoscopía , Fluoroscopía/métodos , Neoplasias Esofágicas/complicaciones , Neoplasias Esofágicas/diagnóstico por imagen , Tomografía Computarizada por Rayos X/métodos , Estudios Retrospectivos
7.
Neuroradiology ; 66(5): 825-834, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38438630

RESUMEN

PURPOSE: The elastase-induced aneurysm (EIA) model in rabbits has been proposed for translational research; however, the adjustment of aneurysm neck size remains challenging. In this study, the technical feasibility and safety of balloon neck-plasty to create a wide-necked aneurysm in rabbit EIA model were investigated. METHODS: Male New Zealand White rabbits (N = 15) were randomly assigned to three groups: group A, EIA creation without neck-plasty; group B, neck-plasty immediately after EIA creation; group C, neck-plasty 4 weeks after EIA creation. The diameter of balloon used for neck-plasty was determined 1 mm larger than origin carotid artery diameter. All rabbits were euthanized 4 weeks after their final surgery. Aneurysm neck, height, dome-to-neck (D/N) ratio, and histologic parameters were compared among the groups. RESULTS: Aneurysm creation was technically successful in 14 out of 15 rabbits (93.3%), with one rabbit experiencing mortality due to an adverse anesthetic event during the surgery. Saccular and wide-necked aneurysms were successfully created in all rabbits. Aneurysm neck was significantly greater in groups B and C compared to group A (all P < .05). D/N ratio was significantly lower in groups B and C compared to group A (all P < .05). Additionally, tunica media thickness, vessel area, and luminal area were significantly greater in groups B and C compared to group A (all P < .05). These variables were found to be significantly greater in group B compared to group C (all P < .05). CONCLUSION: The creation of a wide-necked aneurysm using balloon neck-plasty after elastase induction in rabbits has been determined to be technically feasible and safe.


Asunto(s)
Aneurisma Intracraneal , Masculino , Conejos , Animales , Aneurisma Intracraneal/patología , Elastasa Pancreática/efectos adversos , Modelos Animales de Enfermedad , Arteria Carótida Común
8.
J Child Psychol Psychiatry ; 64(2): 299-310, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36440655

RESUMEN

BACKGROUND: Causal explanations for the association of young motherhood with increased risk for child attention-deficit hyperactivity disorder (ADHD) remain unclear. METHODS: The ABCD Study recruited 11,878 youth from 22 sites across the United States between June 1, 2016 and October 15, 2018. This cross-sectional analysis of 8,514 children aged 8-11 years excluded 2,260 twins/triplets, 265 adopted children, and 839 younger siblings. We examined associations of maternal age with ADHD clinical range diagnoses based on the Child Behavior Checklist and NIH Toolbox Flanker Attention Scores using mixed logistic and linear regression models, respectively. We conducted confounding and causal mediation analyses using genotype array, demographic, socioeconomic, and prenatal environment data to investigate which genetic and environmental variables may explain the association between young maternal age and child ADHD. RESULTS: In crude models, each 10-year increase in maternal age was associated with 32% decreased odds of ADHD clinical range diagnosis (OR = 0.68; 95% CI [0.59, 0.78]) and 1.09-points increased NIH Flanker Attention Scores (ß = 1.09; 95% CI [0.76, 1.41]), indicating better child visual selective attention. However, adjustment for confounders weakened these associations. The strongest confounders were family income, caregiver education, and ADHD polygenic risk score for ADHD clinical range diagnoses, and family income, caregiver education, and race/ethnicity for NIH Flanker Attention Scores. Breastfeeding duration, prenatal alcohol exposure, and prenatal tobacco exposure were responsible for up to 18%, 6%, and 4% mediation, respectively. CONCLUSIONS: Socioeconomic disadvantages were likely the primary explanation for the association of young maternal age with child ADHD, although genetics and modifiable environmental factors also played a role. Public policies aimed at reducing the burden of ADHD associated with young motherhood should target socioeconomic inequalities and support young pregnant women by advocating for reduced prenatal tobacco exposure and healthy breastfeeding practices after childbirth.


Asunto(s)
Trastorno por Déficit de Atención con Hiperactividad , Efectos Tardíos de la Exposición Prenatal , Recién Nacido , Adolescente , Niño , Humanos , Embarazo , Femenino , Edad Materna , Trastorno por Déficit de Atención con Hiperactividad/etiología , Trastorno por Déficit de Atención con Hiperactividad/genética , Estudios Transversales , Efectos Tardíos de la Exposición Prenatal/epidemiología , Parto
9.
Proc Natl Acad Sci U S A ; 117(48): 30805-30815, 2020 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-33199617

RESUMEN

Transcriptional regulation is a complex and pivotal process in living cells. HOS15 is a transcriptional corepressor. Although transcriptional repressors generally have been associated with inactive genes, increasing evidence indicates that, through poorly understood mechanisms, transcriptional corepressors also associate with actively transcribed genes. Here, we show that HOS15 is the substrate receptor for an SCF/CUL1 E3 ubiquitin ligase complex (SCFHOS15) that negatively regulates plant immunity by destabilizing transcriptional activation complexes containing NPR1 and associated transcriptional activators. In unchallenged conditions, HOS15 continuously eliminates NPR1 to prevent inappropriate defense gene expression. Upon defense activation, HOS15 preferentially associates with phosphorylated NPR1 to stimulate rapid degradation of transcriptionally active NPR1 and thus limit the extent of defense gene expression. Our findings indicate that HOS15-mediated ubiquitination and elimination of NPR1 produce effects contrary to those of CUL3-containing ubiquitin ligase that coactivate defense gene expression. Thus, HOS15 plays a key role in the dynamic regulation of pre- and postactivation host defense.


Asunto(s)
Proteínas Co-Represoras/metabolismo , Regulación de la Expresión Génica de las Plantas , Inmunidad de la Planta , Fenómenos Fisiológicos de las Plantas , Proteínas de Plantas/metabolismo , Activación Transcripcional , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas Cromosómicas no Histona/metabolismo , Complejos Multiproteicos , Unión Proteica , Ubiquitina-Proteína Ligasas/metabolismo , Ubiquitinación
10.
Small ; 18(25): e2200316, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-35570584

RESUMEN

To circumvent the limitations of conventional cancer immunotherapy, it is critical to prime antigen-presenting cells (APCs) to initiate the cancer-immune cycle. Here, the authors develop a metal-phenolic network (MPN)-based immunoactive nanoparticle in combination with irreversible electroporation (IRE) for an effective cancer immunotherapy. The MPN nanoparticles are synthesized by coordinating tannic acid with manganese (Mn) ions, and subsequent coating with CpG-oligodeoxynucleotides (CpG-ODNs) via hydrogen bonding. The CpG-ODN-coated Mn-phenolic network (CMP) nanoparticles are effectively internalized into macrophages, a type of APCs, and successfully trigger M1 polarization to promote release of proinflammatory cytokines. Notably, the CMP nanoparticles demonstrate an extended retention time period than the free CpG-ODN in the tumor. The tumor microenvironment tailored bipolar IRE, enhances the therapeutic efficacy by significantly broadening the ablation zone, which further increases immunogenic cell death (ICD). Ultimately, the simultaneous CMP nanoparticles and IRE treatment successfully inhibit tumor growth and prolong survival in a mouse tumor model. Thus, CMP nanoparticles are empowered with Mn and CpG-ODN immunomodulators and the tumor microenvironment tailored bipolar IRE will be a new tool for effective cancer immunotherapy to treat intractable malignancies.


Asunto(s)
Nanopartículas , Neoplasias , Animales , Ratones , Electroporación , Inmunoterapia , Neoplasias/terapia , Microambiente Tumoral
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