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1.
ACS Omega ; 9(17): 18777-18785, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38708220

RESUMO

The solution of wellbore multiphase flow models has an important position in oil-gas field development. However, the solution of multiphase flow models often involves a series of complicated situations such as interphase mass and energy transfer, surface problems, and so on. Foam carrying sand particles in the wellbore is a solid, liquid, and gas three-phase cylinder flow problem. To solve this problem, we developed a computational fluid dynamics-discrete element method model based on the traditional N-S equations to track the streamline of the foam fluid and sand particles in the wellbore. On this basis, we investigated the influence of three factors, i.e., foam and sand properties and wellbore parameters, on the sand carrying rate of foam. The results show that whether the sand mound at the bottom of wells that can be dispersed is mainly affected by the properties of foam. The location of sand deposition in the wellbore and the effectiveness of foam in sand transportation are mainly influenced by the wellbore parameters and sand properties.

2.
Angew Chem Int Ed Engl ; : e202403927, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38632085

RESUMO

All-inorganic metal halides with afterglow emission have attracted increasing attention due to their significantly longer afterglow duration and higher stability compared to their organic-inorganic hybrid counterparts. However, their afterglow colors have not yet reached the blue spectral region. Here, we report all-inorganic copper-doped Rb2AgBr3 single crystals with ultralong blue afterglow (>300 s) by modulating defect states through doping engineering. The introduction of copper(I) ions into Rb2AgBr3 facilitates the formation of bromine vacancies, thus increasing the density of trap states available for charge storage and enabling bright, persistent emission after ceasing the excitation. Moreover, cascade energy transfer between distinct emissive centers in the crystals results in ultra-broadband photoluminescence, not only covering the whole white light with near-unity quantum yield but also extending into the near-infrared region. This 'cocktail' of exotic light-emission properties, in conjunction with the excellent stability of copper-doped Rb2AgBr3 crystals, allowed us to demonstrate their implementation to solid-state lighting, night vision, and intelligent anti-counterfeiting.

3.
ACS Appl Mater Interfaces ; 16(11): 14152-14161, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38469868

RESUMO

The incorporation of two-dimensional (2D) functional nanosheets in polymeric membranes is a promising material strategy to overcome their inherent performance trade-off behavior. Herein, we report a novel nanocomposite membrane design by incorporating MXene, a 2D sheet-like nanoarchitecture known for its advantageous lamellar morphology and surface functionalities, into a cross-linked polyether block amide (Pebax)/poly(ethylene glycol) methyl ether acrylate (PEGMEA) blend matrix, which delivered exceptional CO2/N2 and CO2/H2 separation performances that are critical to industrial CO2 capture applications. The finely dispersed Ti3C2Tx nanosheets in the blend polymer matrix led to an expansion of the free volume within the resultant mixed matrix membrane (MMM), giving rise to a substantially enhanced CO2 permeability of up to 1264.6 barrer, which is 102% higher than that of the pristine polymer. Moreover, these MXene-incorporated MMMs exhibited preferential sorption for CO2 over light gases, which contributed to an exceptional CO2/N2 and CO2/H2 selectivity (64.3 and 19.2, respectively) even at a small loading of only 1 wt %, allowing the overall performance to not only surpass the latest upper bounds but also exceed many previously reported high-performance nanosheet-based nanocomposite membranes. Long-term performance tests have also demonstrated the good stability of these membranes. This composite membrane design strategy reveals the remarkable potential of combining a blend copolymer matrix with ultrathin MXene nanosheets to achieve superior gas separation performance for environmentally important gas separations.

4.
BMJ Open ; 14(3): e081207, 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38531575

RESUMO

INTRODUCTION: The widespread application of extracorporeal membrane oxygenation (ECMO) has enhanced clinical outcomes for patients experiencing cardiac arrest. However, its effectiveness is still limited and falls short of the desired level. Therapeutic hypothermia, which maintains body temperatures between 32°C and 36°C in cardiac arrest patients treated with ECMO, has been proposed as a potential means of neuroprotection and increased survival rates. Nevertheless, it remains controversial, and its impact on patient complications has yet to be fully understood. Thus, this paper aims to update the protocol for a systematic review of patients treated with ECMO and therapeutic hypothermia, in order to explore its effects on survival and neurological function. METHOD AND ANALYSIS: This protocol has been developed in compliance with the Preferred Reporting Items for Systematic Review and Meta-analysis Protocols 2015. The following databases will be systematically searched: PubMed, Web of Science, Cochrane Library, Embase, Ovid, CNKI, Wanfang and China Biology Medicine Disc. The database search strategy will use a combination of subject terms and free-text keywords. The search will encompass articles from the inception of each database up to 15 June 2023. Inclusion criteria encompass randomised controlled trials, cohort studies, case-control studies and quasi-experimental studies. Two researchers will independently review articles and extract relevant data based on these criteria. Any disagreements will be resolved through discussion. Data analysis will be performed using Review Manager software. ETHICS AND DISSEMINATION: Since no patient data were collected in this study, ethical approval was not required. Research findings will be released in a peer-reviewed journal. PROSPERO REGISTRATION NUMBER: CRD42023435353.


Assuntos
Oxigenação por Membrana Extracorpórea , Parada Cardíaca , Hipotermia Induzida , Humanos , Oxigenação por Membrana Extracorpórea/métodos , Revisões Sistemáticas como Assunto , Metanálise como Assunto , Hipotermia Induzida/métodos , Projetos de Pesquisa
5.
Sci Rep ; 14(1): 4296, 2024 02 21.
Artigo em Inglês | MEDLINE | ID: mdl-38383755

RESUMO

The purpose of this study was to evaluate the effect of the Task-Grabbing System on operating room efficiency. Based on the competition-driven concept of the 'Uber' app, an Task-Grabbing System was designed for task allocation and quality assessment. We implemented the Task-Grabbing System in our hospital operating room and compared the differences in consecutive operation preparation time, turnover time, and task completion time performed by surgical technicians for tasks such as patient pick-up, operating room cleaning, medical equipment recovery, three-piece set delivery, as well as blood gas analysis and intraoperative specimen submission before (October 2019) and after (December 2019) the implementation of the Task-Grabbing System. After the implementation of the Task-Grabbing System, the consecutive operation preparation time was reduced from the average of 43.56-38.55 min (P < 0.05), and the turnover time was decreased from the average of 14.25-12.61 min (P < 0.05). And the respective time consuming of surgical technicians for patients picking up, operating room cleaning, medical facilities recovering, the three-piece set delivering, blood gas analysis sending and intraoperative specimen submitting was significantly shortened (P < 0.05). The Task-Grabbing System could improve the operating room efficiency and effectively mobilize the enthusiasm and initiative of the surgical technicians.


Assuntos
Eficiência , Salas Cirúrgicas , Humanos , Hospitais
6.
Front Cell Dev Biol ; 12: 1346996, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38313227

RESUMO

Salivary gland hypofunction (SGH) caused by systemic disease, drugs, aging, and radiotherapy for head and neck cancer can cause dry mouth, which increases the risk of disorders such as periodontitis, taste disorders, pain and burning sensations in the mouth, dental caries, and dramatically reduces the quality of life of patients. To date, the treatment of SGH is still aimed at relieving patients' clinical symptoms and improving their quality of life, and is not able to repair and regenerate the damaged salivary glands. Pluripotent stem cells (PSCs), including embryonic stem cells (ESCs), induced pluripotent stem cells (iPSCs), and extended pluripotent stem cells (EPSCs), are an emerging source of cellular therapies that are capable of unlimited proliferation and differentiation into cells of all three germ layers. In recent years, the immunomodulatory and tissue regenerative effects of PSCs, their derived cells, and paracrine products of these cells have received increasing attention and have demonstrated promising therapeutic effects in some preclinical studies targeting SGH. This review outlined the etiologies and available treatments for SGH. The existing efficacy and potential role of PSCs, their derived cells and paracrine products of these cells for SGH are summarized, with a focus on PSC-derived salivary gland stem/progenitor cells (SGS/PCs) and PSC-derived mesenchymal stem cells (MSCs). In this Review, we provide a conceptual outline of our current understanding of PSCs-based therapy and its importance in SGH treatment, which may inform and serve the design of future studies.

7.
JMIR Serious Games ; 12: e52990, 2024 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-38319697

RESUMO

BACKGROUND: Serious games have emerged as an innovative educational strategy with the potential to significantly enhance the quality and effectiveness of cardiopulmonary resuscitation (CPR) training. Despite their promise, there remains a degree of controversy when comparing the advantages of serious games with traditional CPR training methods. This study seeks to provide a comprehensive assessment of the impact of serious games on CPR training and education by systematically analyzing the results of previous research. OBJECTIVE: This study aimed to assess the effect of serious games on CPR training and education by summarizing and pooling the results of previous studies. METHODS: We conducted a thorough and systematic search across 9 prominent web-based databases, encompassing the period from the inception of these databases until April 1, 2023. The databases included in our search were PubMed, Cochrane Library, Wiley Online Library, EBSCO (PsycInfo), SpringerLink, Chinese Biology Medicine Disc, Vip Journal Integration Platform, Wanfang Database, and Chinese National Knowledge Infrastructure. The studies selected adhered to the following criteria: (1) being a randomized controlled trial comparing serious games and traditional methods for CPR training; (2) having participants aged 12 years or older in CPR; (3) having an experimental group using serious games and a control group using nongame methods for CPR instruction; and (4) having outcomes including theoretical and skill assessments, compression depth, and rate. The Cochrane risk of bias assessment tool was used to evaluate the risk of bias. Data analysis was performed using RevMan (version 5.3; Cochrane Training), and mean differences (MDs) and standardized mean differences (SMDs) with 95% CIs were used to calculate continuous variables. RESULTS: A total of 9 articles were included, involving 791 study participants, of whom 395 in the experimental group taught CPR training using serious games and 396 in the control group taught CPR training using traditional methods. The results of our meta-analysis indicate that the use of serious games in CPR training yields outcomes that are comparable in effectiveness to traditional training methods across several key areas. Specifically, serious games demonstrated equivalence to traditional formats in theory assessment (SMD -0.22, 95% CI - 0.96 to 0.51; P=.55), skill assessment (SMD -0.49, 95% CI -1.52 to 0.55; P=.36), compression depth (MD -3.17, 95% CI -0.18 to 6.53; P=.06), and compression rate (MD -0.20, 95% CI -7.29 to 6.89; P=.96). CONCLUSIONS: In summary, serious games offer a viable and effective CPR education approach, yielding results comparable to traditional formats. This modality is a valuable addition to CPR training methodologies. However, caution is warranted in interpreting these findings due to limited controlled trials, small sample sizes, and low-quality meta-analyzed evidence.

8.
Mar Drugs ; 22(2)2024 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-38393036

RESUMO

Microalgae are considered to be natural producers of bioactive pigments, with the production of pigments from microalgae being a sustainable and economical strategy that promises to alleviate growing demand. Chlorophyll, as the main pigment of photosynthesis, has been widely studied, but its medicinal applications as an antioxidant, antibacterial, and antitumor reagent are still poorly understood. Chlorophyll is the most important pigment in plants and algae, which not only provides food for organisms throughout the biosphere, but also plays an important role in a variety of human and man-made applications. The biological activity of chlorophyll is closely related to its chemical structure; its specific structure offers the possibility for its medicinal applications. This paper reviews the structural and functional roles of microalgal chlorophylls, commonly used extraction methods, and recent advances in medicine, to provide a theoretical basis for the standardization and commercial production and application of chlorophylls.


Assuntos
Microalgas , Humanos , Clorofila/química , Fotossíntese , Antioxidantes/farmacologia , Antioxidantes/química , Plantas
9.
Acta Psychol (Amst) ; 244: 104178, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38340616

RESUMO

The phenomenon of customer incivility poses significant challenges for frontline employees whose expression of emotion determines the service experience. Few studies have explored the mediating mechanisms linking customer incivility to frontline employees' emotional labor. Drawing on the dualistic model of job passion theory, we proposed job passion as a feasible mediator of the links from customer incivility to frontline employees' emotional labor. Using data from 1040 frontline employees across the retailing, banking, and hospitality sectors, the results indicate that job passion acts as the psychological mechanism underlying the relationships between customer incivility and frontline employees' emotional labor. Specifically, customer incivility is positively associated with frontline employees' surface acting through both obsessive passion and harmonious passion. Conversely, customer incivility is negatively linked with deep acting only through harmonious passion. Our findings clarify the psychological mechanisms through which customer incivility affects frontline employees' emotional labor from the perspective of job passion. Furthermore, the current study also extends the job passion model to the boundary-spanning context to explain how frontline employees respond to customer incivility. This study sheds light on how service practitioners can support frontline employees in dealing with customer incivility.


Assuntos
Incivilidade , Humanos , Relações Interpessoais , Emoções , Ansiedade
10.
ACS Appl Mater Interfaces ; 16(2): 2932-2939, 2024 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-38179712

RESUMO

Black silicon (BS), a nanostructured silicon surface containing highly roughened surface morphology, has recently emerged as a promising candidate for field emission (FE) cathodes in novel electron sources due to its huge number of sharp tips with ease of large-scale fabrication and controllable geometrical shapes. However, evaluating the FE performance of BS-based nanostructures with high accuracy is still a challenge due to the increasing complexity in the surface morphology. Here, we demonstrate a 3D modeling methodology to fully characterize highly disordered BS-based field emitters randomly distributed on a roughened nonflat surface. We fabricated BS cathode samples with different morphological features to demonstrate the validity of this method. We utilize parametrized scanning electron microscopy images that provide high-precision morphology details, successfully describing the electric field distribution in field emitters and linking the theoretical analysis with the measured FE property of the complex nanostructures with high precision. The 3D model developed here reveals a relationship between the field emission performance and the density of the cones, successfully reproducing the classical relationship between current density J and electric field E (J-E curve). The proposed modeling approach is expected to offer a powerful tool to accurately describe the field emission properties of large-scale, disordered nano cold cathodes, thus serving as a guide for the design and application of BS as a field electron emission material.

11.
Angew Chem Int Ed Engl ; 63(8): e202319969, 2024 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-38179817

RESUMO

Most of current metal halide materials, including all inorganic and organic-inorganic hybrids, are crystalline materials with poor workability and plasticity that limit their application scope. Here, we develop a novel class of materials termed polymeric metal halides (PMHs) through introducing polycations into antimony-based metal halide materials as A-site cations. A series of PMHs with orange-yellow broadband emission and large Stokes shift originating from inorganic self-trapped excitons are successfully prepared, which meanwhile exhibit the excellent processability and formability of polymers. The versatility of these PMHs is manifested as the broad choices of polycations, the ready extension to manganese- and copper-based halides, and the tolerance to molar ratios between polycations and metal halides in the formation of PMHs. The merger of polymer chemistry and inorganic chemistry thus provides a novel generic platform for the development of metal halide functional materials.

12.
Plant Physiol ; 194(2): 884-901, 2024 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-37944026

RESUMO

A reliable and stable hydrogen gas (H2) supply will benefit agricultural laboratory and field trials. Here, we assessed ammonia borane (AB), an efficient hydrogen storage material used in the energy industry, and determined its effect on plant physiology and the corresponding mechanism. Through hydroponics and pot experiments, we discovered that AB increases tomato (Solanum lycopersicum) lateral root (LR) branching and this function depended on the increased endogenous H2 level caused by the sustainable H2 supply. In particular, AB might trigger LR primordia initiation. Transgenic tomato and Arabidopsis (Arabidopsis thaliana) expressing hydrogenase1 (CrHYD1) from Chlamydomonas reinhardtii not only accumulated higher endogenous H2 and phytomelatonin levels but also displayed pronounced LR branching. These endogenous H2 responses achieved by AB or genetic manipulation were sensitive to the pharmacological removal of phytomelatonin, indicating the downstream role of phytomelatonin in endogenous H2 control of LR formation. Consistently, extra H2 supply failed to influence the LR defective phenotypes in phytomelatonin synthetic mutants. Molecular evidence showed that the phytomelatonin-regulated auxin signaling network and cell-cycle regulation were associated with the AB/H2 control of LR branching. Also, AB and melatonin had little effect on LR branching in the presence of auxin synthetic inhibitors. Collectively, our integrated approaches show that supplying H2 via AB increases LR branching via phytomelatonin signaling. This finding might open the way for applying hydrogen storage materials to horticultural production.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Amônia/farmacologia , Arabidopsis/metabolismo , Proteínas de Arabidopsis/metabolismo , Ácidos Indolacéticos/farmacologia , Hidrogênio , Raízes de Plantas/genética , Regulação da Expressão Gênica de Plantas
13.
Emerg Med Int ; 2023: 6780941, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38035124

RESUMO

Objectives: Prediction models for the return of spontaneous circulation (ROSC) in patients with cardiac arrest play an important role in helping physicians evaluate the survival probability and providing medical decision-making reference. Although relevant models have been developed, their methodological rigor and model applicability are still unclear. Therefore, this study aims to summarize the evidence for ROSC prediction models and provide a reference for the development, validation, and application of ROSC prediction models. Methods: PubMed, Cochrane Library, Embase, Elsevier, Web of Science, SpringerLink, Ovid, CNKI, Wanfang, and SinoMed were systematically searched for studies on ROSC prediction models. The search time limit was from the establishment of the database to August 30, 2022. Two reviewers independently screened the literature and extracted the data. The PROBAST was used to evaluate the quality of the included literature. Results: A total of 8 relevant prediction models were included, and 6 models reported the AUC of 0.662-0.830 in the modeling population, which showed good overall applicability but high risk of bias. The main reasons were improper handling of missing values and variable screening, lack of external validation of the model, and insufficient information of overfitting. Age, gender, etiology, initial heart rhythm, EMS arrival time/BLS intervention time, location, bystander CPR, witnessed during sudden arrest, and ACLS duration/compression duration were the most commonly included predictors. Obvious chest injury, body temperature below 33°C, and possible etiologies were predictive factors for ROSC failure in patients with TOHCA. Age, gender, initial heart rhythm, reason for the hospital visit, length of hospital stay, and the location of occurrence in hospital were the predictors of ROSC in IHCA patients. Conclusion: The performance of current ROSC prediction models varies greatly and has a high risk of bias, which should be selected with caution. Future studies can further optimize and externally validate the existing models.

14.
Curr Neuropharmacol ; 2023 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-37921169

RESUMO

Humans have long been combating chronic pain. In clinical practice, opioids are first- choice analgesics, but long-term use of these drugs can lead to serious adverse reactions. Finding new, safe and effective pain relievers that are useful treatments for chronic pain is an urgent medical need. Based on accumulating evidence from numerous studies, excess reactive oxygen species (ROS) contribute to the development and maintenance of chronic pain. Some antioxidants are potentially beneficial analgesics in the clinic, but ROS-dependent pathways are completely inhibited only by scavenging ROS directly targeting cellular or subcellular sites. Unfortunately, current antioxidant treatments donot achieve this effect. Furthermore, some antioxidants interfere with physiological redox signaling pathways and fail to reverse oxidative damage. Therefore, the key upstream processes and mechanisms of ROS production that lead to chronic pain in vivo must be identified to discover potential therapeutic targets related to the pathways that control ROS production in vivo. In this review, we summarize the sites and pathways involved in analgesia based on the three main mechanisms by which ROS are generated in vivo, discuss the preclinical evidence for the therapeutic potential of targeting these pathways in chronic pain, note the shortcomings of current research and highlight possible future research directions to provide new targets and evidence for the development of clinical analgesics.

15.
Nanotechnology ; 35(7)2023 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-37918030

RESUMO

The all-trans conformation (ß-phase) possesses a significant impact on the piezoelectric polymer polyvinylidene fluoride (PVDF). Inducing more molecular chain [-CH2-CF2-]nto form all-trans conformation is one of the biggest obstacles for manufacturing high-performance piezoelectric sensing devices. Herein, the continuous vacuum technology is used to modulate the polarity of binary solvents by the proportion of the lower solvent. The regulated solvent forms a high dipole moment, an interaction between the dipole ofß-phase and the dipole moment makes the phase reversal in PVDF. Fourier transform infrared spectroscopy, piezoelectric constant test and other characterization results show that when the weakly polar acetone and the strongly polar solvent DMF reach a ratio of 4:6, the pure PVDF film possesses high piezoelectricity (d33∼ -44.8 pC N-1) and strong self-polarization. Additionally, the A4D6device exhibits high sensitivity (S1= 0.182 V/N, 0.5 N ∼ 30 N), driven capability (0.49 mW m-2), and reliability during the electrical tests as a pressure device. This work provides an effective and cost-effective route of optimizing the solvent's polarity to improve the piezoelectric characteristics of the polymer.

16.
Adv Mater ; : e2309459, 2023 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-37878233

RESUMO

Over the past decade, the power conversion efficiency (PCE) of perovskite solar cells (PSCs) has experienced a remarkable ascent, soaring from 3.8% in 2009 to a remarkable record of 26.1% in 2023. Many recent approaches for improving PSC performance employ nanophotonic technologies, from light harvesting and thermal management to the manipulation of charge carrier dynamics. Plasmonic nanoparticles and arrayed dielectric nanostructures have been applied to tailor the light absorption, scattering, and conversion, as well as the heat dissipation within PSCs to improve their PCE and operational stability. In this review, it is begin with a concise introduction to define the realm of nanophotonics by focusing on the nanoscale interactions between light and surface plasmons or dielectric photonic structures. Prevailing strategies that utilize resonance-enhanced light-matter interactions for boosting the PCE and stability of PSCs from light trapping, carrier transportation, and thermal management perspectives are then elaborated, and the resultant practical applications, such as semitransparent photovoltaics, colored PSCs, and smart perovskite windows are discussed. Finally, the state-of-the-art nanophotonic paradigms in PSCs are reviewed, and the benefits of these approaches in improving the aesthetic effects and energy-saving character of PSC-integrated buildings are highlighted.

17.
Bioresour Technol ; 390: 129912, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37879446

RESUMO

This research studied the metabolic mechanism of the mixotrophic Chaetoceros sp. The results showed this alga had the highest cell density and growth rate of 47.72 × 105 cells mL-1 and 0.41 d-1, respectively, with a maximum dry weight of 2.90 g/L, when compared to photoautotrophic and photoheterotrophic modes. Compared to photoheterotrophy, transcriptomics results showed the Rubisco, PGK, and GAPDH related genes were separately up-regulated by 1.03, 2.36, and 1.36 times in CBB cycle in mixotrophic mode, suggesting intermediate metabolites of EMP and PPP can enter the chloroplast via transporter proteins, or membrane permeation, and feedback inhibition regulates the reduction of multiple reactions in CBB cycle. Chaetoceros sp. achieves high biomass by utilizing ATP and carbon structures from EMP and PPP pathways, and the addition of NaHCO3 leads to an up-regulation of CBB cycle for the mixotrophic alga, resulting in higher biomass compared to the photoheterotrophic mode.


Assuntos
Carbono , Metabolismo Energético , Carbono/metabolismo , Perfilação da Expressão Gênica , Biomassa
18.
Plant Physiol ; 193(4): 2734-2749, 2023 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-37625793

RESUMO

Although the sources of molecular hydrogen (H2) synthesis in plants remain to be fully elucidated, ample evidence shows that plant-based H2 can regulate development and stress responses. Here, we present genetic and molecular evidence indicating that nitrate reductase (NR) might be a target of H2 sensing that positively regulates nitrogen use efficiency (NUE) and seed size in Arabidopsis (Arabidopsis thaliana). The expression level of NR and changes of NUE under control and, in particular, low nitrogen supply were positively associated with H2 addition supplied exogenously or through genetic manipulation. The improvement in nitrate assimilation achieved by H2 was also mediated via NR dephosphorylation. H2 control of seed size was impaired by NR mutation. Further genetic evidence revealed that H2, NR, and nitric oxide can synergistically regulate nitrate assimilation in response to N starvation conditions. Collectively, our data indicate that NR might be a target for H2 sensing, ultimately positively regulating nitrate uptake and seed size. These results provide insights into H2 signaling and its functions in plant metabolism.


Assuntos
Arabidopsis , Nitratos , Nitrato Redutase/genética , Nitrato Redutase/metabolismo , Nitratos/metabolismo , Arabidopsis/genética , Arabidopsis/metabolismo , Plantas/metabolismo , Sementes/genética , Sementes/metabolismo , Nitrogênio/metabolismo , Hidrogênio
19.
Org Lett ; 25(34): 6300-6304, 2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-37610822

RESUMO

Herein, we disclose a visible-light-induced oxy-alkynylation of diazo compounds with ethynylbenziodoxolones. The efficient protocol provides a mild and metal-free methodology to synthesize propargylic esters in moderate to good yields. Notably, this metal-free carbene transfer reaction appears to involve an oxonium ylide intermediate, followed by intramolecular ligand exchange and reductive elimination.

20.
J Bone Joint Surg Am ; 105(19): 1527-1536, 2023 10 04.
Artigo em Inglês | MEDLINE | ID: mdl-37603599

RESUMO

BACKGROUND: Osteomyelitis causes marked disability and is one of the most challenging diseases for orthopaedists to treat because of the considerable rate of infection recurrence. In this study, we proposed and assessed the debridement-reconstruction-docking (DRD) system for the treatment of lower-extremity osteomyelitis. This procedure comprises 3 surgical stages and 2 preoperative assessments; namely, pre-debridement assessment, debridement, pre-reconstruction assessment, reconstruction, and docking-site management. We evaluated the use of the DRD system compared with the Ilizarov technique, which is defined as a 1-stage debridement, osteotomy, and bone transport. METHODS: This retrospective cohort included 289 patients who underwent either DRD or the Ilizarov technique for the treatment of lower-extremity osteomyelitis at a single institution between January 2013 and February 2021 and who met the eligibility criteria. The primary outcome was the rate of infection recurrence. Secondary outcomes included the external fixator index (EFI), refracture rate, and the Paley classification for osseous and functional results. An inverse-probability-weighted regression adjustment model was utilized to estimate the effect of the DRD system and Ilizarov technique on the treatment of lower-extremity osteomyelitis. RESULTS: A total of 131 and 158 patients underwent DRD or the Ilizarov technique, respectively. The inverse-probability-weighted regression adjustment model suggested that DRD was associated with a significant reduction in infection recurrence (risk ratio [RR], 0.26; 95% confidence interval [CI], 0.13 to 0.50; p < 0.001) and EFI (-6.9 days/cm, 95% CI; -8.3 to -5.5; p < 0.001). Patients in the DRD group had better Paley functional results than those in the Ilizarov group (ridit score, 0.55 versus 0.45; p < 0.001). There was no significant difference between the 2 groups in the rate of refracture (RR, 0.87; 95% CI, 0.42 to 1.79; p = 0.71) and Paley osseous results (ridit score, 0.51 versus 0.49; p = 0.39). CONCLUSIONS: In this balanced retrospective cohort of patients with lower-extremity osteomyelitis, the use of the DRD system was associated with a reduced rate of infection recurrence, a lower EFI, and better Paley functional results compared with the use of the Ilizarov technique. LEVEL OF EVIDENCE: Therapeutic Level III . See Instructions for Authors for a complete description of levels of evidence.


Assuntos
Técnica de Ilizarov , Osteomielite , Fraturas da Tíbia , Humanos , Técnica de Ilizarov/efeitos adversos , Estudos Retrospectivos , Desbridamento/métodos , Resultado do Tratamento , Fixadores Externos , Osteomielite/cirurgia , Extremidade Inferior/cirurgia , Fraturas da Tíbia/cirurgia , Tíbia/cirurgia
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