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1.
Mol Cell Proteomics ; 22(3): 100510, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36804530

RESUMO

Obstructive nephropathy is one of the leading causes of kidney injury and renal fibrosis in pediatric patients. Although considerable advances have been made in understanding the pathophysiology of obstructive nephropathy, most of them were based on animal experiments and a comprehensive understanding of obstructive nephropathy in pediatric patients at the molecular level remains limited. Here, we performed a comparative proteomics analysis of obstructed kidneys from pediatric patients with ureteropelvic junction obstruction and healthy kidney tissues. Intriguingly, the proteomics revealed extensive metabolic reprogramming in kidneys from individuals with ureteropelvic junction obstruction. Moreover, we uncovered the dysregulation of NAD+ metabolism and NAD+-related metabolic pathways, including mitochondrial dysfunction, the Krebs cycle, and tryptophan metabolism, which led to decreased NAD+ levels in obstructed kidneys. Importantly, the major NADase CD38 was strongly induced in human and experimental obstructive nephropathy. Genetic deletion or pharmacological inhibition of CD38 as well as NAD+ supplementation significantly recovered NAD+ levels in obstructed kidneys and reduced obstruction-induced renal fibrosis, partially through the mechanisms of blunting the recruitment of immune cells and NF-κB signaling. Thus, our work not only provides an enriched resource for future investigations of obstructive nephropathy but also establishes CD38-mediated NAD+ decline as a potential therapeutic target for obstruction-induced renal fibrosis.


Assuntos
NAD , Obstrução Ureteral , Animais , Criança , Humanos , Fibrose , Rim/metabolismo , NAD/metabolismo , Proteômica , Obstrução Ureteral/complicações , Obstrução Ureteral/tratamento farmacológico , Obstrução Ureteral/metabolismo
2.
Nano Lett ; 24(3): 1015-1023, 2024 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-38215497

RESUMO

Ru-related catalysts have shown excellent performance for the hydrogen evolution reaction (HER) and hydrogen oxidation reaction (HOR); however, a deep understanding of Ru-active sites on a nanoscale heterogeneous support for hydrogen catalysis is still lacking. Herein, a click chemistry strategy is proposed to design Ru cluster-decorated nanometer RuxFe3-xO4 heterointerfaces (Ru/RuxFe3-xO4) as highly effective bifunctional hydrogen catalysts. It is found that introducing Ru into nanometric Fe3O4 species breaks the symmetry configuration and optimizes the active site in Ru/RuxFe3-xO4 for HER and HOR. As expected, the catalyst displays prominent alkaline HER and HOR performance with mass activity much higher than that of commercial Pt/C as well as robust stability during catalysis because of the strong interaction between the Ru cluster and the RuxFe3-xO4 support, and the optimized adsorption intermediate (Had and OHad). This work sheds light on a promsing approach to improving the electrocatalysis performance of catalysts by the breaking of atomic dimension symmetry.

3.
BMC Plant Biol ; 24(1): 78, 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-38287275

RESUMO

BACKGROUND: Annexin (ANN) is calcium (Ca2+)-dependent and phospholipid binding protein family, which is involved in plant growth and development and response to various stresses. However, little known about ANN genes were identified from crape myrtle, an ornamental horticultural plant widely cultivated in the world. RESULTS: Here, 9 LiANN genes were identified from Lagerstroemia indica, and their characterizations and functions were investigated in L. indica for the first time. The LiANN genes were divided into 2 subfamilies. The gene structure, chromosomal location, and collinearity relationship were also explored. In addition, the GO annotation analysis of these LiANNs indicated that they are enriched in molecular functions, cellular components, and biological processes. Moreover, transcription factors (TFs) prediction analysis revealed that bHLH, MYB, NAC, and other TFs can interact with the LiANN promoters. Interestingly, the LiANN2/4/6-9 were demonstrated to play critical roles in the branching architecture of crape myrtle. Furthermore, the LiANN2/6/8/9 were differentially expressed under salt treatment, and a series of TFs regulating LiANN2/6/8/9 expression were predicted to play essential roles in salt resistance. CONCLUSIONS: These results shed light on profile and function of the LiANN gene family, and lay a foundation for further studies of the LiANN genes.


Assuntos
Lagerstroemia , Myrtus , Lagerstroemia/genética , Anexinas/genética , Fatores de Transcrição/genética , Estresse Salino/genética , Regulação da Expressão Gênica de Plantas , Filogenia
4.
Inorg Chem ; 63(21): 9983-9991, 2024 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-38757519

RESUMO

Electrocatalytic CO2 reduction reaction (CO2RR) to ethanol has been widely researched for potential commercial application. However, it still faces limited selectivity at a large current density. Herein, Mo4+-doped CuS nanosheet-assembled hollow spheres are constructed to address this issue. Mo4+ ion doping modifies the local electronic environments and diversifies the binding sites of CuS, which increases the coverage of linear *COL and produces bridge *COB for subsequent *COL-*COH coupling toward ethanol production. The optimal Mo9.0%-CuS can electrocatalyze CO2 to ethanol with a faradaic efficiency of 67.5% and a partial current density of 186.5 mA cm-2 at -0.6 V in a flow cell. This work clarifies that doping high valence transition metal ions into Cu-based sulfides can regulate the coverage and configuration of related intermediates for ethanol production during the CO2RR in a flow cell.

5.
Cardiology ; 149(1): 40-50, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37944497

RESUMO

INTRODUCTION: To study the prognostic factors of patients with chest pain and without obstructive coronary artery disease is of great significance for the management of such patients. We assessed whether a high-sensitivity troponin I (hs-TnI) is associated with prognosis in patients with chest pain and without obstructive coronary artery disease. METHODS: From 2011 to 2017, 489 consecutively hospitalized patients with chest pain and without significant coronary artery stenosis (<50%) were tested for hs-TnI and underwent stress myocardial contrast echocardiography (MCE). Myocardial blood flow reserve (MBFR) was measured by stress MCE. Patients were followed (median, 41 months) for composite endpoints, including cardiovascular death and non-fatal myocardial infarction. Cox proportional hazards models were performed to determine associations between hs-TnI and the composite endpoints. RESULTS: Among 489 patients with chest pain and without significant coronary artery stenosis, 257 patients (52.6%) had elevated hs-TnI. Compared to patients with normal hs-TnI, patients with elevated hs-TnI were older (p = 0.013) and had a higher prevalence of atrial fibrillation (p = 0.003), higher left ventricular mass index (p = 0.002) and E/e' septal (p < 0.001), and a lower MBFR (p < 0.001). After adjustment, there was still a significant association between hs-TnI and MBFR (odds ratio = 1.145; 95% confidence interval [CI], 1.079-1.214; p < 0.001). Compared with patients with normal hs-TnI, patients with elevated hs-TnI had a greater cumulative event rate (log-rank p = 0.002). Males (hazard ratio [HR], 4.770; 95% CI, 1.175-19.363; p = 0.029) and reduced MBFR (HR, 2.496; 95% CI, 1.446-4.311; p = 0.001) were risk factors associated with composite endpoints in patients with elevated hs-TnI. CONCLUSIONS: In patients with chest pain and without obstructive coronary artery disease, elevated hs-TnI is associated with decreased myocardial perfusion by contrast echocardiography as well as a higher incidence of cardiovascular events.


Assuntos
Doença da Artéria Coronariana , Estenose Coronária , Infarto do Miocárdio , Masculino , Humanos , Doença da Artéria Coronariana/diagnóstico por imagem , Infarto do Miocárdio/epidemiologia , Prognóstico , Troponina I , Estenose Coronária/diagnóstico por imagem , Dor no Peito/etiologia , Biomarcadores
6.
Mol Biol Rep ; 51(1): 263, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38302771

RESUMO

BACKGROUND: TRIM proteins, recognized as a class of E3 ubiquitin ligases, are increasingly acknowledged for their antipathogen immune functions in mammals and fish. In the Chinese soft-shelled turtle (Pelodiscus sinensis), a secondary aquatic reptile that occupies a unique evolutionary position, the TRIM gene has rarely been reported. METHODS AND RESULTS: In the present study, 48 PsTRIM proteins were identified from the genome of Pelodiscus sinensis via Hidden Markov Model (HMM) searches and Signal Transduction ATPases with Numerous Domains (SMART) analysis. These PsTRIMs were found across 43 distinct scaffolds, and phylogenetic analyses classified them into three principal clades. The PsTRIMs feature a conserved assembly of either RING-B-box-coiled-coil (RBCC) or B-box-coiled-coil (BBC) domains at the N-terminus, in addition to eight unique domains at the C-terminus, including the B30.2 domain, 19 of which were identified. Expression profiling revealed ubiquitous expression of the 48 PsTRIMs across various P. sinensis tissues. Notably, seven PsTRIMs exhibited significant differential expression in liver transcriptomes following infection with Aeromonas hydrophila. Weighted gene coexpression network analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis implicated PsTRIM14 and PsTRIM28 as key players in host defense against bacterial invasion. Real-time quantitative PCR results indicated that PsTRIM1, PsTRIM2, PsTRIM14, and PsTRIM28 experienced marked upregulation in P. sinensis livers at 12 h post-infection with A. hydrophila. CONCLUSIONS: Our study is the first to comprehensively identify and analyze the functions of TRIM genes in P. sinensis, unveiling their considerable diversity and potential roles in modulating immune responses.


Assuntos
Transcriptoma , Tartarugas , Animais , Aeromonas hydrophila , Genômica , Filogenia , Transcriptoma/genética , Proteínas com Motivo Tripartido/genética , Tartarugas/genética
7.
Anesth Analg ; 138(4): 839-847, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-37307232

RESUMO

BACKGROUND: Dexmedetomidine was reported to reduce postoperative acute pain after neurosurgery. However, the efficacy of dexmedetomidine for preventing chronic incisional pain is uncertain. METHODS: This article is a secondary analysis of a randomized, double-blind, placebo-controlled trial. Eligible patients were randomly allocated to either the dexmedetomidine group or the placebo group. Patients assigned to the dexmedetomidine group were given a 0.6 µg kg -1 dexmedetomidine bolus followed by a 0.4 µg kg -1 h -1 maintenance dose until dural closure; placebo patients were given comparable amounts of normal saline. The primary end point was the incidence of incisional pain at 3 months after craniotomy evaluated by numerical rating scale scores and defined as any score >0. The secondary end points were postoperative acute pain scores, sleep quality, and Short-Form McGill Pain Questionnaire (SF-MPQ-2) at 3 months after craniotomy. RESULTS: From January 2021 to December 2021, a total of 252 patients were included in the final analysis: the dexmedetomidine group (n = 128) and the placebo group (n = 124). The incidence of chronic incisional pain was 23.4% (30 of 128) in the dexmedetomidine group versus 42.7% (53 of 124) in the placebo group (risk ratio, 0.55; 95% confidence interval, 0.38-0.80; P = .001). The overall severity of chronic incisional pain was mild in both groups. Patients in the dexmedetomidine group had lower acute pain severity on movement than those in the placebo group for the first 3 days after surgery (all adjusted P < .01). Sleep quality did not differ between groups. However, the SF-MPQ-2 total sensory ( P = .01) and neuropathic pain descriptor ( P = .023) scores in the dexmedetomidine group were lower than those in the placebo group. CONCLUSIONS: Prophylactic intraoperative dexmedetomidine infusion reduces the incidence of chronic incisional pain as well as acute pain score after elective brain tumor resections.


Assuntos
Dor Aguda , Analgésicos não Narcóticos , Neoplasias Encefálicas , Dor Crônica , Dexmedetomidina , Humanos , Dexmedetomidina/uso terapêutico , Analgésicos não Narcóticos/uso terapêutico , Dor Aguda/tratamento farmacológico , Dor Pós-Operatória/diagnóstico , Dor Pós-Operatória/prevenção & controle , Dor Pós-Operatória/tratamento farmacológico , Neoplasias Encefálicas/cirurgia , Dor Crônica/diagnóstico , Dor Crônica/epidemiologia , Dor Crônica/prevenção & controle , Craniotomia/efeitos adversos , Método Duplo-Cego
8.
J Am Chem Soc ; 2023 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-37923566

RESUMO

It remains a challenge to design a catalyst with high selectivity at a large current density toward CO2 electrocatalytic reduction (CO2ER) to a single C1 liquid product of methanol. Here, we report the design of a catalyst by integrating MnO2 nanosheets with Pd nanoparticles to address this challenge, which can be implemented in membrane electrode assembly (MEA) electrolyzers for the conversion of CO2ER to methanol. Such a strategy modifies the electronic structure of the catalyst and provides additional active sites, favoring the formation of key reaction intermediates and their successive evolution into methanol. The optimal catalyst delivers a Faradaic efficiency of 77.6 ± 1.3% and a partial current density of 250.8 ± 4.3 mA cm-2 for methanol during CO2ER in an MEA electrolyzer by coupling anodic oxygen evolution reaction with a full-cell energy efficiency achieving 29.1 ± 1.2% at 3.2 V. This work opens a new avenue to the control of C1 intermediates for CO2ER to methanol with high selectivity and activity in an MEA electrolyzer.

9.
Inorg Chem ; 62(41): 16986-16993, 2023 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-37773890

RESUMO

Electrochemical reduction of carbon dioxide to value-added multicarbon (C2+) products is a promising way to obtain renewable fuels of high energy densities and chemicals and close the carbon cycle. However, the difficulty of C-C coupling and complexity of the proton-coupled electron transfer process greatly hinder CO2 electroreduction into specific C2+ products with high selectivity. Here, we design an electrocatalyst of Sr-doped CuO nanoribbons with a hydrophobic surface for CO2 electroreduction to ethane with high selectivity. Sr doping enhances the chemical adsorption and activation of CO2 by inducing oxygen vacancies and increasing *CO coverage by stabilizing Cu2+ active sites, thus further boosting subsequent C-C coupling. The hydrophobic surface with dodecyl sulfate anions (DS-) adsorption increases the oxophilicity of the catalyst surface, enhancing the conversion of the *OCH2CH3 intermediate to ethane. As a result, the optimized Sr1.97%-CuO exhibits a Faradaic efficiency of 53.4% and a partial current density of 13.5 mA cm-2 for ethane under a potential of -0.8 V. This study provides a strategy to design a Cu-based catalyst by alkaline earth metal ions doping with the hydrophobic surface to engineer the evolution of the intermediates for a desired product during CO2RR.

10.
Br J Anaesth ; 130(2): e307-e316, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36517290

RESUMO

BACKGROUND: Delirium is common, especially after neurosurgery. Dexmedetomidine might reduce delirium by improving postoperative analgesia and sleep quality. We tested the primary hypothesis that dexmedetomidine administration during intracerebral tumour resection reduces the incidence of postoperative delirium. METHODS: This randomised, double-blind, placebo-controlled trial was conducted in two tertiary-care hospitals in Beijing. We randomised 260 qualifying patients to either dexmedetomidine (n=130) or placebo (n=130). Subjects assigned to dexmedetomidine were given a loading dose of 0.6 µg kg-1 followed by continuous infusion at 0.4 µg kg-1 h-1 until dural closure; subjects in the placebo group were given comparable volumes of normal saline. The primary outcome was the incidence of delirium, which was assessed with the Confusion Assessment Method twice daily during the initial 5 postoperative days. RESULTS: The average (standard deviation) age of participating patients was 45 (12) yr, duration of surgery was 4.2 (1.5) h, and patients assigned to dexmedetomidine were given an average of 126 (45) µg of dexmedetomidine. There was less delirium during the initial 5 postoperative days in patients assigned to dexmedetomidine (22%, 28 of 130 patients) than in those given placebo (46%, 60 of 130 patients) with a risk ratio of 0.51 (95% confidence interval: 0.36-0.74, P<0.001). Postoperative pain scores with movement, and recovery and sleep quality were improved by dexmedetomidine (P<0.001). The incidence of safety outcomes was similar in each group. CONCLUSIONS: Prophylactic intraoperative dexmedetomidine infusion reduced by half the incidence of delirium during the initial 5 postoperative days in patients recovering from elective brain tumour resection. CLINICAL TRIAL REGISTRATION: NCT04674241.


Assuntos
Neoplasias Encefálicas , Delírio , Dexmedetomidina , Delírio do Despertar , Humanos , Dexmedetomidina/uso terapêutico , Delírio/etiologia , Dor Pós-Operatória/prevenção & controle , Dor Pós-Operatória/tratamento farmacológico , Neoplasias Encefálicas/cirurgia , Método Duplo-Cego
11.
Small ; 18(40): e2204155, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36050884

RESUMO

The coordination environment of Ru centers determines their catalytic performance, however, much less attention is focused on cluster-induced charge transfer in a Ru single-atom system. Herein, by density functional theory (DFT) calculations, a competitive coordination-pairing between Ru clusters (RuRu bond) and single-atoms (RuO bond) is revealed leading to the charge redistribution between Ru and O atoms in ZnFe2 O4 units which share more free electrons to participate in the hydrogen desorption process, optimizing the proton adsorption and hydrogen desorption. Thus, a clicking confinement strategy for building a competitive coordination-pairing between Ru clusters and single-atoms anchored on ZnFe2 Ox nanosheets over carbon via RuO ligand (Ru1, n -ZnFe2 Ox -C) is proposed. Benefiting from the optimized coordination effect and the electronic synergy between Ru clusters and single-atoms, such a catalyst demonstrates the excellent activity and excellent stability in alkaline and seawater media, which has exceptional hydrogen evolution reaction activity with overpotentials as low as 10.1 and 15.9 mV to reach the current density of 10 mA cm-2 in alkaline and seawater media, respectively, higher than that of commercial Pt/C catalysts as a benchmark. Furthermore, it owns remarkably outstanding mass activity, approximately 2 and 8 times higher than that of Pt catalysts in alkaline and seawater media, respectively.

12.
Glob Chang Biol ; 25(2): 686-698, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30449058

RESUMO

Rice is a staple food for nearly half of the world's population, but rice paddies constitute a major source of anthropogenic CH4 emissions. Root exudates from growing rice plants are an important substrate for methane-producing microorganisms. Therefore, breeding efforts optimizing rice plant photosynthate allocation to grains, i.e., increasing harvest index (HI), are widely expected to reduce CH4 emissions with higher yield. Here we show, by combining a series of experiments, meta-analyses and an expert survey, that the potential of CH4 mitigation from rice paddies through HI improvement is in fact small. Whereas HI improvement reduced CH4 emissions under continuously flooded (CF) irrigation, it did not affect CH4 emissions in systems with intermittent irrigation (II). We estimate that future plant breeding efforts aimed at HI improvement to the theoretical maximum value will reduce CH4 emissions in CF systems by 4.4%. However, CF systems currently make up only a small fraction of the total rice growing area (i.e., 27% of the Chinese rice paddy area). Thus, to achieve substantial CH4 mitigation from rice agriculture, alternative plant breeding strategies may be needed, along with alternative management.


Assuntos
Poluentes Atmosféricos/análise , Produção Agrícola/métodos , Recuperação e Remediação Ambiental/métodos , Gases de Efeito Estufa/análise , Metano/análise , Poluição do Ar/prevenção & controle , Oryza/crescimento & desenvolvimento
13.
Acc Chem Res ; 50(1): 86-95, 2017 01 17.
Artigo em Inglês | MEDLINE | ID: mdl-28032510

RESUMO

One of the greatest challenges in using H2 as a fuel source is finding a safe, efficient, and inexpensive method for its storage. Ammonia borane (AB) is a solid hydrogen storage material that has garnered attention for its high hydrogen weight density (19.6 wt %) and ease of handling and transport. Hydrogen release from ammonia borane is mediated by either hydrolysis, thus giving borate products that are difficult to rereduce, or direct dehydrogenation. Catalytic AB dehydrogenation has thus been a popular topic in recent years, motivated both by applications in hydrogen storage and main group synthetic chemistry. This Account is a complete description of work from our laboratory in ruthenium-catalyzed ammonia borane dehydrogenation over the last 6 years, beginning with the Shvo catalyst and resulting ultimately in the development of optimized, leading catalysts for efficient hydrogen release. We have studied AB dehydrogenation with Shvo's catalyst extensively and generated a detailed understanding of the role that borazine, a dehydrogenation product, plays in the reaction: it is a poison for both Shvo's catalyst and PEM fuel cells. Through independent syntheses of Shvo derivatives, we found a protective mechanism wherein catalyst deactivation by borazine is prevented by coordination of a ligand that might otherwise be a catalytic poison. These studies showed how a bidentate N-N ligand can transform the Shvo into a more reactive species for AB dehydrogenation that minimizes accumulation of borazine. Simultaneously, we designed novel ruthenium catalysts that contain a Lewis acidic boron to replace the Shvo -OH proton, thus offering more flexibility to optimize hydrogen release and take on more general problems in hydride abstraction. Our scorpionate-ligated ruthenium species (12) is a best-of-class catalyst for homogeneous dehydrogenation of ammonia borane in terms of its extent of hydrogen release (4.6 wt %), air tolerance, and reusability. Moreover, a synthetically simplified ruthenium complex supported by the inexpensive bis(pyrazolyl)borate ligand is a comparably good catalyst for AB dehydrogenation, among other reactions. In this Account, we present a detailed, concise description of how our work with the Shvo system progressed to the development of our very reactive and flexible dual-site boron-ruthenium catalysts.

15.
J Ethnopharmacol ; 328: 118097, 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38531432

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Cistanche tubulosa (CT) is the dried fleshy stem with scaly leaves of Cistanche tubiflora (Schenk) Wight, which has the effects of tonifying the kidney-yang, benefiting the vital essence and blood, and moisturizing the intestines and laxatives. There are differences in the activity of CT before and after processing, but the mechanism of processing is not clear. AIM OF THE STUDY: The study aimed to compare the strength of action of CT before and after yellow-wine processing in the treatment of constipation and kidney yang deficiency and to identify the active ingredients responsible for the differences in activity before and after yellow-wine processing. MATERIALS AND METHODS: This study established the fingerprints of CT and PCT using HPLC to identify their shared components. Then efficacy of KYDS and FC were carried out to compare the differences between CT and PCT in terms of efficacy. Next, this study established the spectrum-effect relationship between the shared chemical components and the medical effects of CT and PCT using the gray correlation analysis and entropy methods. Ultimately, the activity of the analyzed chemical components was verified using the zebrafish model. RESULTS: CT was more effective than PCT in promoting intestinal peristalsis, regulating gastrointestinal hormone levels, and thus treating FC. PCT was more effective than CT in improving the level of hormone indexes of the hypothalamus-pituitary-target gland axis, replenishing blood, and enhancing immunity. Through the analysis of the spectrum-effect relationship, it was finally found that 5, 6, 12 (tubuloside A), and 13 (isoacteoside) might be more closely related to the activity of tonifying kidney yang, and peaks 9, 10, and 11 (acteoside) are more closely associated with the treatment of constipation, and peaks 3 (salidroside), 4, 1, 2 (geniposidic acid), and 8 (echinacoside) were associated with both kidney yang tonic and treatment of constipation. At the same time, an activity verification experiment showed that echinacoside, geniposidic acid, and salidroside were effective in the treatment of FC and KYDS, while acteoside was very effective in the treatment of FC, and tubuloside A was significant in supplementing the blood, which validated the spectrum-effect relationship analysis. CONCLUSION: This study proved that the raw CT had a better laxative effect, while the yellow-wine processed CT had a better kidney-yang tonic effect; moreover, spectrum-effect relationships were established to analyze the chemical components leading to changes in the activity of CT before and after yellow-wine processing.


Assuntos
Cistanche , Glucosídeos , Glucosídeos Iridoides , Fenóis , Polifenóis , Animais , Quimiometria , Peixe-Zebra , Glicosídeos/farmacologia , Glicosídeos/uso terapêutico , Constipação Intestinal
16.
PhytoKeys ; 237: 257-268, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38333592

RESUMO

Lysimachiadanxiashanensis, a new Primulaceae species, endemic to the Danxia landscape in Guangdong Province, China, is described and illustrated. This new species is morphologically similar to L.pseudohenryi, L.phyllocephala, L.congestiflora and L.kwangtungensis, but it differs from the similar species by its purplish-red plants, petiole without wings, calyx with orange glandular and the corolla margin serrated on upper half with orange-red glandular punctates. This new species belongs to Lysimachiasubgen.Lysimachiasect.Nummularia. Phylogenetic analysis confirmed that L.danxiashanensis is a distinct clade, based on the combined data of ITS and rbcL sequences. The conservation status of the new species was evaluated as Endangered (EN) according to IUCN Red List Categories and Criteria.

17.
Plant Physiol Biochem ; 212: 108738, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38761544

RESUMO

In the realm of ornamental horticulture, crape myrtle (Lagerstroemia indica) stands out for its aesthetic appeal, attributed largely to its vibrant flowers and distinctive branching architecture. This study embarked on a comprehensive exploration of the gibberellin oxidase (GAox) gene family in crape myrtle, illuminating its pivotal role in regulating GA levels, a key determinant of plant developmental processes. We identified and characterized 36 LiGAox genes, subdivided into GA2ox, GA3ox, GA20ox, and GAox-like subgroups, through genomic analyses. These genes' evolutionary trajectories were delineated, revealing significant gene expansions attributed to segmental duplication events. Functional analyses highlighted the divergent expression patterns of LiGAox genes across different crape myrtle varieties, associating them with variations in flower color and branching architecture. Enzymatic activity assays on selected LiGA2ox enzymes exhibited pronounced GA2 oxidase activity, suggesting a potential regulatory role in GA biosynthesis. Our findings offered a novel insight into the molecular underpinnings of GA-mediated growth and development in L. indica, providing a foundational framework for future genetic enhancements aimed at optimizing ornamental traits.


Assuntos
Regulação da Expressão Gênica de Plantas , Oxigenases de Função Mista , Proteínas de Plantas , Oxigenases de Função Mista/metabolismo , Oxigenases de Função Mista/genética , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Giberelinas/metabolismo , Flores/genética , Flores/crescimento & desenvolvimento , Flores/anatomia & histologia , Flores/enzimologia , Filogenia
18.
Int J Biol Macromol ; 266(Pt 1): 131095, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38537859

RESUMO

Gibberellin oxidases (GAoxs) identified from many species play indispensable roles in GA biosynthesis and GA signal transduction. However, there has been limited research conducted on the GAox family of Salix matsudana, a tetraploid ornamental tree species. Here, 54 GAox genes were identified from S. matsudana and renamed as SmGA20ox1-22, SmGA2ox1-24, SmGA3ox1-6, and SmGAox-like1/2. Gene structure and conserved motif analysis showed that SmGA3ox members possess the 1 intron and other SmGAoxs contain 2-3 introns, and motif 1/2/7 universally present in all SmGAoxs. A total of 69 gene pairs were identified from SmGAox family members, and the Ka/Ks values indicated the SmGAoxs experience the purifying selection. The intra species collinearity analysis implied S. matsudana, S. purpurea, and Populus trichocarpa have the close genetic relationship. The GO analysis suggested SmGAoxs are dominantly involved in GA metabolic process, ion binding, and oxidoreductase activity. RNA-sequencing demonstrated that some SmGAoxs may play an essential role in salt and submergence stresses. In addition, the SmGA20ox13/21 displayed the dominant vitality of GA20 oxidase, but the SmGA20ox13/21 still possessed low activities of GA2 and GA3 oxidases. This study can contribute to reveal the regulatory mechanism of salt and submergence tolerance in willow.


Assuntos
Regulação da Expressão Gênica de Plantas , Giberelinas , Oxigenases de Função Mista , Filogenia , Salix , Perfilação da Expressão Gênica , Giberelinas/metabolismo , Oxigenases de Função Mista/genética , Oxigenases de Função Mista/metabolismo , Oxigenases de Função Mista/química , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Proteínas de Plantas/química , Salix/genética
19.
J Org Chem ; 78(5): 1971-6, 2013 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-23227945

RESUMO

Semitheoretical Brönsted correlations are compared between previously measured experimental rates of hydrogen isotope exchange of substituted toluenes labeled in the α-position and relative equilibrium acidities computed at several theory levels. The Brönsted correlations show less scatter at the Hartree-Fock level than at higher theory levels. This effect is rationalized on the basis of enhanced steric effects in the more constrained structures of the higher theory levels.

20.
Math Biosci Eng ; 20(9): 16762-16785, 2023 08 23.
Artigo em Inglês | MEDLINE | ID: mdl-37920033

RESUMO

In recent years, the global outbreak of COVID-19 has posed an extremely serious life-safety risk to humans, and in order to maximize the diagnostic efficiency of physicians, it is extremely valuable to investigate the methods of lesion segmentation in images of COVID-19. Aiming at the problems of existing deep learning models, such as low segmentation accuracy, poor model generalization performance, large model parameters and difficult deployment, we propose an UNet segmentation network integrating multi-scale attention for COVID-19 CT images. Specifically, the UNet network model is utilized as the base network, and the structure of multi-scale convolutional attention is proposed in the encoder stage to enhance the network's ability to capture multi-scale information. Second, a local channel attention module is proposed to extract spatial information by modeling local relationships to generate channel domain weights, to supplement detailed information about the target region to reduce information redundancy and to enhance important information. Moreover, the network model encoder segment uses the Meta-ACON activation function to avoid the overfitting phenomenon of the model and to improve the model's representational ability. A large number of experimental results on publicly available mixed data sets show that compared with the current mainstream image segmentation algorithms, the pro-posed method can more effectively improve the accuracy and generalization performance of COVID-19 lesions segmentation and provide help for medical diagnosis and analysis.


Assuntos
COVID-19 , Humanos , COVID-19/diagnóstico por imagem , COVID-19/epidemiologia , Algoritmos , Surtos de Doenças , Tomografia Computadorizada por Raios X , Processamento de Imagem Assistida por Computador
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