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1.
Genome Res ; 2024 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-38914436

RESUMO

3'-end cleavage and polyadenylation is an essential process for eukaryotic mRNA maturation. In yeast species, the polyadenylation signals that recruit the processing machinery are degenerate and remain poorly characterized compared to the well-defined regulatory elements in mammals. Here we address this question by developing deep learning models to deconvolute degenerate cis-regulatory elements and quantify their positional importance in mediating yeast poly(A) site formation, cleavage heterogeneity, and strength. In S. cerevisiae, cleavage heterogeneity is promoted by the depletion of U-rich elements around poly(A) sites as well as multiple occurrences of upstream UA-rich elements. Sites with high cleavage heterogeneity show overall lower strength. The site strength and tandem site distances modulate alternative polyadenylation (APA) under the diauxic stress. Finally, we develop a deep learning model to reveal the distinct motif configuration of S. pombe poly(A) sites, which show more precise cleavage than S. cerevisiae Altogether, our deep learning models provide unprecedented insights into poly(A) site formation of yeast species, and our results highlight divergent poly(A) signals across distantly related species.

2.
Genome Res ; 32(3): 545-557, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35193938

RESUMO

We describe a low-input RNase footprinting approach for the rapid quantification of ribosome-protected fragments with as few as 1000 cultured cells. The assay uses a simplified procedure to selectively capture ribosome footprints based on optimized RNase digestion. It simultaneously maps cytosolic and mitochondrial translation with single-nucleotide resolution. We applied it to reveal selective functions of the elongation factor TUFM in mitochondrial translation, as well as synchronized repression of cytosolic translation after TUFM perturbation. We show the assay is applicable to small amounts of primary tissue samples with low protein synthesis rates, including snap-frozen tissues and immune cells from an individual's blood draw. We showed its feasibility to characterize the personalized immuno-translatome. Our analyses revealed that thousands of genes show lower translation efficiency in monocytes compared with lymphocytes, and identified thousands of translated noncanonical open reading frames (ORFs). Altogether, our RNase footprinting approach opens an avenue to assay transcriptome-wide translation using low-input samples from a wide range of physiological conditions.


Assuntos
Biossíntese de Proteínas , Ribonucleases , Fases de Leitura Aberta , RNA Mensageiro/genética , Ribonucleases/genética , Ribonucleases/metabolismo , Ribossomos/metabolismo
3.
J Biol Chem ; 299(8): 105016, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37414151

RESUMO

The biosynthesis of glycosylphosphatidylinositol (GPI)-anchored proteins (GPI-APs) in the parasitic protozoan Trypanosoma brucei involves fatty acid remodeling of the GPI precursor molecules before they are transferred to protein in the endoplasmic reticulum. The genes encoding the requisite phospholipase A2 and A1 activities for this remodeling have thus far been elusive. Here, we identify a gene, Tb927.7.6110, that encodes a protein that is both necessary and sufficient for GPI-phospholipase A2 (GPI-PLA2) activity in the procyclic form of the parasite. The predicted protein product belongs to the alkaline ceramidase, PAQR receptor, Per1, SID-1, and TMEM8 (CREST) superfamily of transmembrane hydrolase proteins and shows sequence similarity to Post-GPI-Attachment to Protein 6 (PGAP6), a GPI-PLA2 that acts after transfer of GPI precursors to protein in mammalian cells. We show the trypanosome Tb927.7.6110 GPI-PLA2 gene resides in a locus with two closely related genes Tb927.7.6150 and Tb927.7.6170, one of which (Tb927.7.6150) most likely encodes a catalytically inactive protein. The absence of GPI-PLA2 in the null mutant procyclic cells not only affected fatty acid remodeling but also reduced GPI anchor sidechain size on mature GPI-anchored procyclin glycoproteins. This reduction in GPI anchor sidechain size was reversed upon the re-addition of Tb927.7.6110 and of Tb927.7.6170, despite the latter not encoding GPI precursor GPI-PLA2 activity. Taken together, we conclude that Tb927.7.6110 encodes the GPI-PLA2 of GPI precursor fatty acid remodeling and that more work is required to assess the roles and essentiality of Tb927.7.6170 and the presumably enzymatically inactive Tb927.7.6150.


Assuntos
Glicosilfosfatidilinositóis , Trypanosoma brucei brucei , Animais , Glicosilfosfatidilinositóis/genética , Glicosilfosfatidilinositóis/metabolismo , Trypanosoma brucei brucei/genética , Trypanosoma brucei brucei/metabolismo , Ácidos Graxos/genética , Ácidos Graxos/metabolismo , Proteínas de Membrana/metabolismo , Fosfolipases A2/metabolismo , Proteínas Ligadas por GPI/metabolismo , Proteínas de Protozoários/genética , Proteínas de Protozoários/metabolismo , Mamíferos/metabolismo
4.
Plant Cell ; 33(3): 566-580, 2021 05 05.
Artigo em Inglês | MEDLINE | ID: mdl-33955496

RESUMO

The external application of nitrogen (N) fertilizers is an important practice for increasing crop production. However, the excessive use of fertilizers significantly increases production costs and causes environmental problems, making the improvement of crop N-use efficiency (NUE) crucial for sustainable agriculture in the future. Here we show that the rice (Oryza sativa) NUE quantitative trait locus DULL NITROGEN RESPONSE1 (qDNR1), which is involved in auxin homeostasis, reflects the differences in nitrate (NO3-) uptake, N assimilation, and yield enhancement between indica and japonica rice varieties. Rice plants carrying the DNR1indica allele exhibit reduced N-responsive transcription and protein abundance of DNR1. This, in turn, promotes auxin biosynthesis, thereby inducing AUXIN RESPONSE FACTOR-mediated activation of NO3- transporter and N-metabolism genes, resulting in improved NUE and grain yield. We also show that a loss-of-function mutation at the DNR1 locus is associated with increased N uptake and assimilation, resulting in improved rice yield under moderate levels of N fertilizer input. Therefore, modulating the DNR1-mediated auxin response represents a promising strategy for achieving environmentally sustainable improvements in rice yield.


Assuntos
Ácidos Indolacéticos/metabolismo , Mutação com Perda de Função/genética , Nitrogênio/metabolismo , Oryza/genética , Oryza/metabolismo , Alelos , Homeostase/genética , Homeostase/fisiologia
5.
Opt Lett ; 49(13): 3737-3740, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38950255

RESUMO

An approach for continuous tuning of on-chip optical delay with a microring resonator is proposed and demonstrated. By introducing an electro-optically tunable waveguide coupler, the bus waveguide to the resonance coupling can be effectively tuned from the under-coupling regime to the over-coupling regime. The optical delay is experimentally characterized by measuring the relative phase shift between lasers and shows a large dynamic range of delay from -600 to 600 ps and an efficient tuning of delay from -430 to -180 ps and from 40 to 240 ps by only a 5 V voltage.

6.
Int J Colorectal Dis ; 39(1): 69, 2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38717476

RESUMO

PURPOSE: This study aimed to investigate the impact of tumor size on survival in early-onset colon and rectal cancer. METHODS: Early-onset colon and rectal cancer patients were identified from the Surveillance, Epidemiology, and End Results (SEER) database between 2004 and 2015. Tumor size was analyzed as both continuous and categorical variables. Several statistical techniques, including restricted cubic spline (RCS), Cox proportional hazard model, subgroup analysis, propensity score matching (PSM), and Kaplan-Meier survival analysis, were employed to demonstrate the association between tumor size and overall survival (OS) and cancer-specific survival (CSS) of early-onset colon and rectal cancer. RESULTS: Seventeen thousand five hundred fifty-one (76.7%) early-onset colon and 5323 (23.3%) rectal cancer patients were included. RCS analysis confirmed a linear association between tumor size and survival. Patients with a tumor size > 5 cm had worse OS and CSS, compared to those with a tumor size ≤ 5 cm for both early-onset colon and rectal cancer. Notably, subgroup analysis showed that a smaller tumor size (≤ 50 mm) was associated with worse survival in stage II early-onset colon cancer, although not statistically significant. After PSM, Kaplan-Meier survival curves showed that the survival of patients with tumor size ≤ 50 mm was better than that of patients with tumor size > 50 mm. CONCLUSION: Patients with tumors larger than 5 cm were associated with worse survival in early-onset colon and rectal cancer. However, smaller tumor size may indicate a more biologically aggressive phenotype, correlating with poorer survival in stage II early-onset colon cancer.


Assuntos
Idade de Início , Neoplasias do Colo , Neoplasias Retais , Carga Tumoral , Humanos , Masculino , Feminino , Neoplasias Retais/patologia , Neoplasias Retais/mortalidade , Neoplasias do Colo/patologia , Neoplasias do Colo/mortalidade , Estudos Retrospectivos , Pessoa de Meia-Idade , Adulto , Estimativa de Kaplan-Meier , Programa de SEER , Estadiamento de Neoplasias , Modelos de Riscos Proporcionais , Idoso
7.
Appl Opt ; 63(7): 1719-1726, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38437271

RESUMO

On-chip acousto-optic modulators that operate at an optical wavelength of 780 nm and a microwave frequency of 6.835 GHz are proposed. The modulators are based on a lithium-niobate-on-sapphire platform and efficiently excite surface acoustic waves and exhibit strong interactions with tightly confined optical modes in waveguides. In particular, a high-efficiency phase modulator and single-sideband mode converter are designed. We found that for both microwave and optical wavelengths below 1 µm, the interactions at the cross-sections of photonic waveguides are sensitive to the waveguide width and are significantly different from those in previous studies. Our designed devices have small footprints and high efficiencies, making them suitable for controlling rubidium atoms and realizing hybrid photonic-atomic chips. Furthermore, our devices have the potential to extend the acousto-optic modulators to other visible wavelengths for other atom transitions and for visible light applications, including imaging and sensing.

8.
Aesthetic Plast Surg ; 48(7): 1473-1486, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38286898

RESUMO

Botulinum toxin type A (BTXA) has the potential to treat androgenetic alopecia (AGA); however, its impact on the apoptosis of dermal papillary cells (DPCs) is not yet fully understood. Noncoding RNAs play a crucial role in AGA. In this study, we investigated the potential mechanism by which BTXA alleviates apoptosis induced by dihydrotestosterone (DHT) in DPCs. We assessed the mRNA levels of circ_0135062, miR-506-3p, and Bax using qRT-PCR. Binding interactions were analyzed using RNA pulldown and dual-luciferase assays. Cell viability was determined using a cell counting kit-8 assay, and cell apoptosis was assessed using flow cytometry, TUNEL assays, and western blotting. Our findings revealed that BTXA inhibited the apoptosis of DPCs treated with DHT. Moreover, circ_0135062 overexpression counteracted the protective effect of BTXA on DHT-treated DPCs. MiR-506-3p was found to interact with Bax and inhibit apoptosis in DPCs by suppressing Bax expression in response to DHT-induced damage. Furthermore, circ_0135062 acted as a sponge for miR-506-3p, thereby inhibiting the targeting of Bax expression by miR-506-3p. In conclusion, BTXA exhibited an antiapoptotic effect on DHT-induced DPC injury via the circ_0135062/miR-506-3p/Bax axis.Level of Evidence II This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

9.
J Am Chem Soc ; 145(26): 14324-14334, 2023 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-37353221

RESUMO

Metal-organic frameworks (MOFs) have emerged as a class of porous materials with facile uptake and release of water, turning them into excellent substrates for real-world atmospheric water harvesting applications. The performance of different MOF systems was experimentally characterized at the bulk level by assessing the total amount of water taken up and the release kinetics, leaving the question behind of what the upper limit of the pristine materials actually is. Moreover, recent devices rely on fluidized bed reactors that exploit the harvesting capacities of MOFs at the single-crystal (SC) level. In this publication, we present a novel methodology based on Raman spectroscopy, for acquiring water adsorption isotherms and kinetic curves with a sub-micrometer resolution that provides valuable insights into the material behavior probing the pristine MOF at the SC level. We investigated isolated MOF-801 particles in situ and could dissect contributions of intra- and inter-particle effects on the water harvesting performance of MOF-801 via adsorption-desorption isotherms and kinetic curves. Using spontaneous Raman spectroscopy, we found an almost 20-fold faster uptake for the undisturbed crystalline material. Correlative imaging based on four-wave mixing and coherent anti-Stokes Raman scattering further localized the uptaken water inside MOF-801 and identified inter-particle condensation as the main source for the discrepancies between the performance at the bulk and SC level. Our studies determined an upper limit of around 91.9 L/kgMOF/day for MOF-801.

10.
Development ; 147(14)2020 07 26.
Artigo em Inglês | MEDLINE | ID: mdl-32631829

RESUMO

Transcription factors (TFs) are often used repeatedly during development and homeostasis to control distinct processes in the same and/or different cellular contexts. Considering the limited number of TFs in the genome and the tremendous number of events that need to be regulated, re-use of TFs is necessary. We analyzed how the expression of the homeobox TF, orthodenticle homeobox 2 (Otx2), is regulated in a cell type- and stage-specific manner during development in the mouse retina. We identified seven Otx2 cis-regulatory modules (CRMs), among which the O5, O7 and O9 CRMs mark three distinct cellular contexts of Otx2 expression. We discovered that Otx2, Crx and Sox2, which are well-known TFs regulating retinal development, bind to and activate the O5, O7 or O9 CRMs, respectively. The chromatin status of these three CRMs was found to be distinct in vivo in different retinal cell types and at different stages. We conclude that retinal cells use a cohort of TFs with different expression patterns and multiple CRMs with different chromatin configurations to regulate the expression of Otx2 precisely.


Assuntos
Fatores de Transcrição Otx/metabolismo , Elementos Reguladores de Transcrição/genética , Retina/metabolismo , Fatores de Transcrição/metabolismo , Animais , Cromatina/metabolismo , Fase G2 , Células HEK293 , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/metabolismo , Humanos , Camundongos , Mutagênese , Fatores de Transcrição Otx/antagonistas & inibidores , Fatores de Transcrição Otx/genética , Células Fotorreceptoras de Vertebrados/citologia , Células Fotorreceptoras de Vertebrados/metabolismo , Ligação Proteica , Interferência de RNA , RNA Interferente Pequeno/metabolismo , Retina/crescimento & desenvolvimento , Fatores de Transcrição SOXB1/genética , Fatores de Transcrição SOXB1/metabolismo , Transativadores/genética , Transativadores/metabolismo , Fatores de Transcrição/genética
11.
Opt Lett ; 48(4): 1064-1067, 2023 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-36791011

RESUMO

Single atoms are interesting candidates for studying quantum optics and quantum information processing. Recently, trapping and manipulation of single atoms using tight optical dipole traps has generated considerable interest. Here we report an experimental investigation of the dynamics of atoms in a modified optical dipole trap with a backward propagating dipole trap beam, where a change in the two-atom collision rate by six times has been achieved. The theoretical model presented gives a prediction of high probabilities of few-atom loading rates under proper experimental conditions. This work provides an alternative approach to the control of the few-atom dynamics in a dipole trap and the study of the collective quantum optical effects of a few atoms.

12.
FASEB J ; 36(11): e22623, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36269304

RESUMO

Many studies have shown that graphene oxide (GO) promotes proliferation and differentiation of a variety of stem cells. However, its effect on adipose-derived mesenchymal stem cell (Ad-MSCs) apoptosis is still unclear. Apoptosis is a significant factor affecting stem cell-based treatment of diabetic wounds. Therefore, we explored the effect of GO on Ad-MSC apoptosis and diabetic wound healing. In this study, qRT-PCR was used to detect Ad-MSC expression of LncRNAs, miRNAs, and mRNAs under high-glucose environment. RNA immunoprecipitation (RIP), RNA pull-down, and luciferase assays were used to detect interactions of specific lncRNAs, miRNAs, and mRNAs. The effects of GO on Ad-MSC apoptosis were explored by flow cytometry, TUNEL assay, and Western blot. A diabetic wound model was used to explore the function of Linc00324 on Ad-MSC reparative properties in vivo. As a result, GO inhibited high glucose-induced apoptosis in Ad-MSCs, and Linc00324 contributed to the anti-apoptotic effect of GO. RIP and RNA pull-down confirmed that Linc00324 directly interacted with miR-7977, functioning as a miRNA sponge to regulate expression of the miR-7977 target gene STK4 (MST1) and downstream signaling pathways. In addition, GO reduced the apoptosis of Ad-MSCs in wounds and promoted wound healing. Taken together, these findings suggest GO may be a superior auxiliary material for Ad-MSCs to facilitate diabetic wound healing via the Linc00324/miR-7977/STK4 pathway.


Assuntos
Diabetes Mellitus , Grafite , Células-Tronco Mesenquimais , MicroRNAs , RNA Longo não Codificante , Cicatrização , Humanos , Apoptose/efeitos dos fármacos , Diabetes Mellitus/metabolismo , Glucose/farmacologia , Glucose/metabolismo , Luciferases/metabolismo , Células-Tronco Mesenquimais/metabolismo , MicroRNAs/efeitos dos fármacos , MicroRNAs/genética , MicroRNAs/metabolismo , Proteínas Serina-Treonina Quinases/efeitos dos fármacos , Proteínas Serina-Treonina Quinases/metabolismo , RNA Longo não Codificante/efeitos dos fármacos , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Cicatrização/efeitos dos fármacos , Cicatrização/fisiologia , Grafite/farmacologia , Grafite/uso terapêutico
13.
Eur Arch Psychiatry Clin Neurosci ; 273(2): 493-509, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36094570

RESUMO

Insomnia disorder (ID) and obstructive sleep apnea (OSA) are the two most prevalent sleep disorders worldwide, but the pathological mechanism has not been fully understood. Functional neuroimaging findings indicated regional abnormal neural activities existed in both diseases, but the results were inconsistent. This meta-analysis aimed to explore concordant regional functional brain changes in ID and OSA, respectively. We conducted a coordinate-based meta-analysis (CBMA) of resting-state functional magnetic resonance imaging (rs-fMRI) studies using the anisotropic effect-size seed-based d mapping (AES-SDM) approach. Studies that applied regional homogeneity (ReHo), amplitude of low-frequency fluctuations (ALFF) or fractional ALFF (fALFF) to analyze regional spontaneous brain activities in ID or OSA were included. Meta-regressions were then applied to investigate potential associations between demographic variables and regional neural activity alterations. Significantly increased brain activities in the left superior temporal gyrus (STG.L) and right superior longitudinal fasciculus (SLF.R), as well as decreased brain activities in several right cerebral hemisphere areas were identified in ID patients. As for OSA patients, more distinct and complicated functional activation alterations were identified. Several neuroimaging alterations were functionally correlated with mean age, duration or illness severity in two patients groups revealed by meta-regressions. These functionally altered areas could be served as potential targets for non-invasive brain stimulation methods. This present meta-analysis distinguished distinct brain function changes in ID and OSA, improving our knowledge of the neuropathological mechanism of these two most common sleep disturbances, and also provided potential orientations for future clinical applications.Registration number: CRD42022301938.


Assuntos
Apneia Obstrutiva do Sono , Distúrbios do Início e da Manutenção do Sono , Humanos , Distúrbios do Início e da Manutenção do Sono/diagnóstico por imagem , Mapeamento Encefálico/métodos , Imageamento por Ressonância Magnética/métodos , Encéfalo/diagnóstico por imagem , Apneia Obstrutiva do Sono/complicações , Apneia Obstrutiva do Sono/diagnóstico por imagem
14.
Cryobiology ; 112: 104562, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37494976

RESUMO

Carbohydrate, lipid and protein, the three main storage reserves of seeds, are the main sources of raw materials and energy for seed germination and early growth stage of seedlings. In this study, the seed of 16 Asteraceae herbaceous ornamentals were used to compare the changes in seed germination, seedling growth indexes and four major storage reserves of seeds before and after cryopreservation. After cryopreservation, seed germination and seedling growth were preserved in most species (11/16), while one species showed significantly improved post-thaw germination and four had decreased germination. In seeds with preserved germination, no clear variation was noted with regards to the four kinds of storage reserves, or only a slight change in one. However, significantly reduced soluble protein, soluble sugar and fat content and increased starch content were detected in seeds showing reduced germination after cryopreservation. The correlation study further showed that the changes in seed germination were positively correlated with soluble protein, soluble sugar and fat, and negatively correlated with starch. In seedling growth indexes, only cotyledon area was correlated to the content of soluble protein, starch, fat, and seed germination after cryopreservation. These results support the use of soluble protein, soluble sugar, starch and fat as indicators of seed germination after cryopreservation, but not for predicting the seedling growth indexes.


Assuntos
Asteraceae , Plântula , Germinação , Criopreservação/métodos , Sementes , Amido/metabolismo , Açúcares
15.
Aquac Nutr ; 2023: 6306517, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37288328

RESUMO

Ammonia is a key risk factor in intensive aquaculture systems. This experiment is aimed at investigating the influence of dietary protein levels on genetically improved farmed tilapia (GIFT, Oreochromis niloticus) under chronic ammonia stress. GIFT juveniles of 4.00 ± 0.55 g were exposed to high ammonia level at 0.88 mg/L and fed with six diets comprising graded protein levels at 22.64%, 27.26%, 31.04%, 35.63%, 38.47%, and 42.66% for 8 weeks. The fish in negative control was fed the diet with 31.04% protein in normal water (0.02 mg ammonia/L water). Our results showed that high ammonia exposure (0.88 mg/L) caused significant decrease in fish growth performance, hematological parameters, liver antioxidant enzymes (catalase and glutathione peroxidase), and gill Na+- and K+-dependent adenosine triphosphatase (Na+/K+-ATP) activity. When fish were under high ammonia exposure, the weight gain rate, special growth rate, feed efficiency, and survival rate elevated significantly with dietary protein supplementation increase to 35.63%, whereas protein efficiency ratio, hepatosomatic index, and viscerosomatic index showed a decreased tendency. Dietary protein administration significantly enhanced crude protein but reduced crude lipid contents in the whole fish. Fish fed diets with 35.63%-42.66% protein had higher red blood cell counts and hematocrit percentage than fish fed 22.64% protein diet. The values of serum biochemical indices (lactate dehydrogenase, aspartate aminotransferase, and alanine aminotransferase), hepatic antioxidant enzymes (superoxide dismutase, catalase, and glutathione peroxidase), and gill Na+/K+-ATP activity were all elevated with the increment of dietary protein. Moreover, histological analysis indicated that dietary protein administration could prevent the ammonia-induced damages in fish gill, kidney, and liver tissues. Based on weight gain rate as a response criterion, the optimal dietary protein requirement for GIFT juveniles under chronic ammonia stress was 37.9%.

16.
J Neuroradiol ; 50(2): 209-216, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36041561

RESUMO

BACKGROUND AND PURPOSE: Currently available methods for determining aneurysm growth are not accurate enough. Therefore, we introduced a more intuitive and accurate 3D registration technology (3DRT) to judge the growth of aneurysms. MATERIALS AND METHODS: We developed an in-house technique for 3DRT and calculated its derivative parameters, voxel change rate (VCR), maximum growth vector (MGV), and parent artery coincidence (PAC). To verify the accuracy, growing aneurysms and stable aneurysms matching 1:3 were selected, and a 3DRT measurement was performed. We calculated the sensitivity, specificity, and accuracy of cases with VCR > 20%, MGV > 1 mm, and combined indicator of VCR > 20% + MGV >1 mm. In addition, we analyzed the cause of the poor registration effect, where the registration effect of PAC > 0.7 was considered acceptable. We also collected 24 consecutive aneurysms for agreement analysis of 2D manual measurement and 3DRT. RESULTS: Twenty-seven growing aneurysms and 81 stable aneurysms were included in the normal model group, and 88 aneurysms with good registration effect in the adjusted model group. For aneurysms with VCR > 20%, the sensitivity and the specificity were the highest at 81.48% and 91.35%, respectively, while in the adjusted model group, the sensitivity and the specificity increased to 94.44% and 94.29%, respectively. When using VCR > 20% as the growth metric, the AUC value in the normal and the adjusted model group was 0.856 and 0.947, respectively. The ICC between 2D manual measurements and the 3DRT was 0.95 (95%CI: 0.88-0.98), and the time spent between the two groups had a significant difference (10.96 min vs. 3.44 min, p<0.01, 95% CI, 6.49-8.53). CONCLUSIONS: A 3DRT can be used to determine the growth of the aneurysm more efficiently, intuitively, and accurately.


Assuntos
Aneurisma Roto , Aneurisma Intracraniano , Humanos
17.
J Am Chem Soc ; 144(48): 22289-22294, 2022 12 07.
Artigo em Inglês | MEDLINE | ID: mdl-36399691

RESUMO

A compound bound covalently to an enzyme active site can act either as a substrate if the covalent linkage is readily broken up by the enzyme or as an inhibitor if the bond dissociates slowly. We tracked the reactivity of such bonds associated with the rise of the resistance to penicillin G (PenG) in protein evolution from penicillin-binding proteins (PBPs) to TEM ß-lactamases and with the development of avibactam (Avb) to overcome the resistance. We found that the ester linkage in PBP-PenG is resistant to hydrolysis mainly due to the small electric fields present in the protein active site. Conversely, the same linkage in the descendant TEM-PenG experiences large electric fields that stabilize the more charge-separated transition state and thus lower the free energy barrier to hydrolysis. Specifically, the electric fields were improved from -59 to -140 MV/cm in an ancient evolution dating back billions of years, contributing 5 orders of magnitude rate acceleration. This trend continues today in the nullification of newly developed antibiotic drugs. The fast linkage hydrolysis acquired from evolution is counteracted by the upgrade of PenG to Avb whose linkage escapes from the hydrolysis by returning to a low-field environment. Using the framework of electrostatic catalysis, the electric field, an observable from vibrational spectroscopy, provides a unifying physical metric to understand protein evolution and to guide the design of covalent drugs.


Assuntos
Antibacterianos , beta-Lactamases , Antibacterianos/farmacologia , Domínio Catalítico
18.
J Am Chem Soc ; 144(45): 20947-20954, 2022 11 16.
Artigo em Inglês | MEDLINE | ID: mdl-36324090

RESUMO

The widespread design of covalent drugs has focused on crafting reactive groups of proper electrophilicity and positioning toward targeted amino-acid nucleophiles. We found that environmental electric fields projected onto a reactive chemical bond, an overlooked design element, play essential roles in the covalent inhibition of TEM-1 ß-lactamase by avibactam. Using the vibrational Stark effect, the magnitudes of the electric fields that are exerted by TEM active sites onto avibactam's reactive C═O were measured and demonstrate an electrostatic gating effect that promotes bond formation yet relatively suppresses the reverse dissociation. These results suggest new principles of covalent drug design and off-target site prediction. Unlike shape and electrostatic complementary which address binding constants, electrostatic catalysis drives reaction rates, essential for covalent inhibition, and deepens our understanding of chemical reactivity, selectivity, and stability in complex systems.


Assuntos
Compostos Azabicíclicos , beta-Lactamases , Compostos Azabicíclicos/química , beta-Lactamases/metabolismo , Domínio Catalítico , Eletricidade Estática , Inibidores de beta-Lactamases/farmacologia
19.
Planta ; 255(5): 94, 2022 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-35347454

RESUMO

MAIN CONCLUSION: Genetic analysis reveals a previously unknown role for ethylene signaling in regulating Arabidopsis thaliana nitrogen metabolism. Nitrogen (N) is essential for plant growth, and assimilation of soil nitrate (NO3-) and ammonium ions is an important route of N acquisition. Although N import and assimilation are subject to multiple regulatory inputs, the extent to which ethylene signaling contributes to this regulation remains poorly understood. Here, our analysis of Arabidopsis thaliana ethylene signaling mutants advances that understanding. We show that the loss of CTR1 function ctr1-1 mutation confers resistance to the toxic effects of the NO3- analogue chlorate (ClO3-), and reduces the activity of the nitrate reductase (NR) enzyme of NO3- assimilation. Our further analysis indicates that the lack of the downstream EIN2 component (conferred by novel ein2 mutations) suppresses the effect of ctr1-1, restoring ClO3- sensitivity and NR activity to normal. Collectively, our observations indicate an important role for ethylene signaling in regulating Arabidopsis thaliana NO3- metabolism. We conclude that ethylene signaling enables environmentally responsive coordination of plant growth and N metabolism.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Etilenos/metabolismo , Nitratos/metabolismo , Transdução de Sinais
20.
BMC Cardiovasc Disord ; 22(1): 445, 2022 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-36243693

RESUMO

BACKGROUND: Success rate of transcatheter aortic valve replacement (TAVR) in aortic regurgitation (AR) patients is relatively low on account of the absence of calcified anchoring structures. Morphological classification and corresponding TAVR strategies for AR are lacking yet. METHODS: The AURORA study is a prospective, multicenter, single-arm cohort study to evaluate the safety and efficacy of transfemoral TAVR for severe AR in patients with high or prohibitive risk for surgery. Patients who are ≥ 65 years and diagnosed with severe pure AR as defined by the Echocardiographic Core Laboratory will be consecutively enrolled for further multidetector computed tomography (MDCT) scanning and multiplanar analyses. Based on a new anatomical classification and dual anchoring theory, patients will be classified into 4 types according to the level of the anchoring area. Types 1, 2 and 3 (at least 2 anchoring areas) will undergo the TAVR procedure with a domestic Chinese self-expanding valve (VitaFlow Valve, MicroPort, Shanghai, China), whereas type 4 (0 or 1 anchoring area) patients will be considered unsuitable for TAVR and will receive medical treatment. Our goal is to recruit 100 patients to account for 10% missing data or loss of patients to follow-up. Procedural, 30-day, 6-month and 12-month outcomes will be assessed according to Valve Academic Research Consortium-3 criteria. DISCUSSION: The AURORA study will establish a new AR anatomical classification based on dual anchoring theory through MDCT multiplanar measurement and assess the safety and efficacy of TAVR guided by this new classification and strategy in AR patients. TRIAL REGISTRATION: This Study was registered at Chinses Clinical Trial Registry. The registration number: ChiCTR2200055415; The date of registration: 9, January 2022; The URL of the registration: http://www.chictr.org.cn/showproj.aspx?proj=141209 .


Assuntos
Insuficiência da Valva Aórtica , Estenose da Valva Aórtica , Próteses Valvulares Cardíacas , Substituição da Valva Aórtica Transcateter , Valva Aórtica/diagnóstico por imagem , Valva Aórtica/cirurgia , Insuficiência da Valva Aórtica/diagnóstico por imagem , Insuficiência da Valva Aórtica/etiologia , Insuficiência da Valva Aórtica/cirurgia , Estenose da Valva Aórtica/cirurgia , China , Estudos de Coortes , Humanos , Estudos Prospectivos , Desenho de Prótese , Fatores de Risco , Substituição da Valva Aórtica Transcateter/efeitos adversos , Resultado do Tratamento
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