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1.
Proc Natl Acad Sci U S A ; 121(29): e2323040121, 2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-38985761

RESUMO

Stomata in leaves regulate gas (carbon dioxide and water vapor) exchange and water transpiration between plants and the atmosphere. SLow Anion Channel 1 (SLAC1) mediates anion efflux from guard cells and plays a crucial role in controlling stomatal aperture. It serves as a central hub for multiple signaling pathways in response to environmental stimuli, with its activity regulated through phosphorylation via various plant protein kinases. However, the molecular mechanism underlying SLAC1 phosphoactivation has remained elusive. Through a combination of protein sequence analyses, AlphaFold-based modeling and electrophysiological studies, we unveiled that the highly conserved motifs on the N- and C-terminal segments of SLAC1 form a cytosolic regulatory domain (CRD) that interacts with the transmembrane domain(TMD), thereby maintaining the channel in an autoinhibited state. Mutations in these conserved motifs destabilize the CRD, releasing autoinhibition in SLAC1 and enabling its transition into an activated state. Our further studies demonstrated that SLAC1 activation undergoes an autoinhibition-release process and subsequent structural changes in the pore helices. These findings provide mechanistic insights into the activation mechanism of SLAC1 and shed light on understanding how SLAC1 controls stomatal closure in response to environmental stimuli.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Estômatos de Plantas , Transdução de Sinais , Fosforilação , Estômatos de Plantas/metabolismo , Proteínas de Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Arabidopsis/metabolismo , Arabidopsis/genética , Proteínas de Membrana/metabolismo , Proteínas de Membrana/genética , Domínios Proteicos , Mutação
2.
Plant Cell ; 35(9): 3604-3625, 2023 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-37325884

RESUMO

Catalase (CAT) is often phosphorylated and activated by protein kinases to maintain hydrogen peroxide (H2O2) homeostasis and protect cells against stresses, but whether and how CAT is switched off by protein phosphatases remains inconclusive. Here, we identified a manganese (Mn2+)-dependent protein phosphatase, which we named PHOSPHATASE OF CATALASE 1 (PC1), from rice (Oryza sativa L.) that negatively regulates salt and oxidative stress tolerance. PC1 specifically dephosphorylates CatC at Ser-9 to inhibit its tetramerization and thus activity in the peroxisome. PC1 overexpressing lines exhibited hypersensitivity to salt and oxidative stresses with a lower phospho-serine level of CATs. Phosphatase activity and seminal root growth assays indicated that PC1 promotes growth and plays a vital role during the transition from salt stress to normal growth conditions. Our findings demonstrate that PC1 acts as a molecular switch to dephosphorylate and deactivate CatC and negatively regulate H2O2 homeostasis and salt tolerance in rice. Moreover, knockout of PC1 not only improved H2O2-scavenging capacity and salt tolerance but also limited rice grain yield loss under salt stress conditions. Together, these results shed light on the mechanisms that switch off CAT and provide a strategy for breeding highly salt-tolerant rice.


Assuntos
Oryza , Catalase/genética , Catalase/metabolismo , Oryza/metabolismo , Peróxido de Hidrogênio/metabolismo , Proteína Fosfatase 1/metabolismo , Tolerância ao Sal/genética , Homeostase , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
3.
Circ Res ; 132(2): 154-166, 2023 01 20.
Artigo em Inglês | MEDLINE | ID: mdl-36575984

RESUMO

BACKGROUND: Hydrogen sulfide is a critical endogenous signaling molecule that exerts protective effects in the setting of heart failure. Cystathionine γ-lyase (CSE), 1 of 3 hydrogen-sulfide-producing enzyme, is predominantly localized in the vascular endothelium. The interaction between the endothelial CSE-hydrogen sulfide axis and endothelial-mesenchymal transition, an important pathological process contributing to the formation of fibrosis, has yet to be investigated. METHODS: Endothelial-cell-specific CSE knockout and Endothelial cell-CSE overexpressing mice were subjected to transverse aortic constriction to induce heart failure with reduced ejection fraction. Cardiac function, vascular reactivity, and treadmill exercise capacity were measured to determine the severity of heart failure. Histological and gene expression analyses were performed to investigate changes in cardiac fibrosis and the activation of endothelial-mesenchymal transition. RESULTS: Endothelial-cell-specific CSE knockout mice exhibited increased endothelial-mesenchymal transition and reduced nitric oxide bioavailability in the myocardium, which was associated with increased cardiac fibrosis, impaired cardiac and vascular function, and worsened exercise performance. In contrast, genetic overexpression of CSE in endothelial cells led to increased myocardial nitric oxide, decreased endothelial-mesenchymal transition and cardiac fibrosis, preserved cardiac and endothelial function, and improved exercise capacity. CONCLUSIONS: Our data demonstrate that endothelial CSE modulates endothelial-mesenchymal transition and ameliorate the severity of pressure-overload-induced heart failure, in part, through nitric oxide-related mechanisms. These data further suggest that endothelium-derived hydrogen sulfide is a potential therapeutic for the treatment of heart failure with reduced ejection fraction.


Assuntos
Insuficiência Cardíaca , Sulfeto de Hidrogênio , Disfunção Ventricular Esquerda , Camundongos , Animais , Sulfeto de Hidrogênio/metabolismo , Células Endoteliais/metabolismo , Óxido Nítrico/metabolismo , Camundongos Knockout , Endotélio Vascular/metabolismo , Fibrose
4.
Nano Lett ; 24(15): 4649-4657, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38572971

RESUMO

Deep-seated bacterial infections (DBIs) are stubborn and deeply penetrate tissues. Eliminating deep-seated bacteria and promoting tissue regeneration remain great challenges. Here, a novel radical-containing hydrogel (SFT-B Gel) cross-linked by a chaotropic effect was designed for the sensing of DBIs and near-infrared photothermal therapy (NIR-II PTT). A silk fibroin solution stained with 4,4',4″-(1,3,5-triazine-2,4,6-triyl)tris(1-methylpyridin-1-ium) (TPT3+) was employed as the backbone, which could be cross-linked by a closo-dodecaborate cluster (B12H122-) through a chaotropic effect to form the SFT-B Gel. More interestingly, the SFT-B Gel exhibited the ability to sense DBIs, which could generate a TPT2+• radical with obvious color changes in the presence of bacteria. The radical-containing SFT-B Gel (SFT-B★ Gel) possessed strong NIR-II absorption and a remarkable photothermal effect, thus demonstrating excellent NIR-II PTT antibacterial activity for the treatment of DBIs. This work provides a new approach for the construction of intelligent hydrogels with unique properties using a chaotropic effect.


Assuntos
Fototerapia , Terapia Fototérmica , Hidrogéis/farmacologia
5.
Circ Res ; 131(3): 222-235, 2022 07 22.
Artigo em Inglês | MEDLINE | ID: mdl-35701874

RESUMO

BACKGROUND: Hydrogen sulfide (H2S) exerts mitochondria-specific actions that include the preservation of oxidative phosphorylation, biogenesis, and ATP synthesis, while inhibiting cell death. 3-MST (3-mercaptopyruvate sulfurtransferase) is a mitochondrial H2S-producing enzyme whose functions in the cardiovascular disease are not fully understood. In the current study, we investigated the effects of global 3-MST deficiency in the setting of pressure overload-induced heart failure. METHODS: Human myocardial samples obtained from patients with heart failure undergoing cardiac surgeries were probed for 3-MST protein expression. 3-MST knockout mice and C57BL/6J wild-type mice were subjected to transverse aortic constriction to induce pressure overload heart failure with reduced ejection fraction. Cardiac structure and function, vascular reactivity, exercise performance, mitochondrial respiration, and ATP synthesis efficiency were assessed. In addition, untargeted metabolomics were utilized to identify key pathways altered by 3-MST deficiency. RESULTS: Myocardial 3-MST was significantly reduced in patients with heart failure compared with nonfailing controls. 3-MST KO mice exhibited increased accumulation of branched-chain amino acids in the myocardium, which was associated with reduced mitochondrial respiration and ATP synthesis, exacerbated cardiac and vascular dysfunction, and worsened exercise performance following transverse aortic constriction. Restoring myocardial branched-chain amino acid catabolism with 3,6-dichlorobenzo1[b]thiophene-2-carboxylic acid (BT2) and administration of a potent H2S donor JK-1 ameliorates the detrimental effects of 3-MST deficiency in heart failure with reduced ejection fraction. CONCLUSIONS: Our data suggest that 3-MST derived mitochondrial H2S may play a regulatory role in branched-chain amino acid catabolism and mediate critical cardiovascular protection in heart failure.


Assuntos
Insuficiência Cardíaca , Sulfeto de Hidrogênio , Disfunção Ventricular Esquerda , Trifosfato de Adenosina/metabolismo , Aminoácidos de Cadeia Ramificada/metabolismo , Animais , Insuficiência Cardíaca/metabolismo , Humanos , Sulfeto de Hidrogênio/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Mitocôndrias/metabolismo , Miocárdio/metabolismo , Disfunção Ventricular Esquerda/metabolismo
6.
Biomacromolecules ; 25(6): 3554-3565, 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38729918

RESUMO

Hydrogels are considered as a potential cartilage replacement material based on their structure being similar to natural cartilage, which are of great significance in repairing cartilage defects. However, it is difficult for the existing hydrogels to combine the high load bearing and low friction properties (37 °C) of cartilage through sample methods. Herein, we report a facile and new fabrication strategy to construct the PNIPAm/EYL hydrogel by using the macrophase separation of supersaturated N-isopropylacrylamide (NIPAm) monomer solution to promote the formation of liposomes from egg yolk lecithin (EYL) and asymmetric template method. The PNIPAm/EYL hydrogels possess a relatively high compressive strength (more than 12 MPa), fracture energy (9820 J/m2), good fatigue resistance, lubricating properties, and excellent biocompatibility. Compared with the PNIPAm hydrogel, the friction coefficient (COF 0.046) of PNIPAm/EYL hydrogel is reduced by 50%. More importantly, the COF (0.056) of PNIPAm/EYL hydrogel above lower critical solution temperature (LCST) does not increase significantly, exhibiting heat-tolerant lubricity. The finite element analysis further proves that PNIPAm/EYL hydrogel can effectively disperse the applied stress and dissipate energy under load conditions. This work not only provides new insights for the design of high-strength lubricating hydrogels but also lays a foundation for the treatment of cartilage injury as a substitute material.


Assuntos
Resinas Acrílicas , Hidrogéis , Hidrogéis/química , Resinas Acrílicas/química , Animais , Temperatura Alta , Lubrificantes/química , Cartilagem/química , Lecitinas/química , Força Compressiva , Lipossomos/química , Gema de Ovo/química , Materiais Biocompatíveis/química
7.
Inorg Chem ; 63(6): 3075-3082, 2024 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-38295520

RESUMO

Herein, an unprecedented cadmium-based metal-organic framework (JNU-106) fabricated by utilizing pyrazole-functionalized tetraphenylethylene ligands (Py-TPE) and rod-shaped secondary building units is reported, possessing a new (3,3,3,6,6,8)-connected topological network. Thanks to the ingeniously designed intramolecular charge transfer behavior, which originates from the congruent coplanarity between Py and TPE, JNU-106 exhibits intense green luminescence with a quantum yield increased by 1.5 times. The phenomenon of remarkable fluorescence quenching of JNU-106 reveals that it possesses extremely high anti-interference performance, superior sensitivity, and dedicated selectivity toward tetracycline antibiotics (TCAs) in aqueous solutions, which are comparable to those of the state-of-the-art porous sensing compounds. Taking the theoretical calculations and experimental results into account, the luminescence quenching is mainly attributed to the internal filtration effect and the static quenching effect. Considering the portable and rapid performance of JNU-106-based testing strips for sensing TCAs, the fabricated JNU-106 provides an alternative for ecological monitoring and environmental governance.

8.
Artigo em Inglês | MEDLINE | ID: mdl-38551441

RESUMO

Objective: This study examines the dynamic changes of stress hormones, including insulin (INS), fasting blood glucose (FBG), glucagon (Glu), and cortisol (Cort), in trauma patients. By monitoring these changes and observing acute pressure injury (API) occurrences on the skin, the research analyzes the influence of stress hormones on API development in trauma patients. Methods: A prospective analysis involved 218 trauma patients admitted to a grade III-A general hospital in Wenzhou from April 2021 to June 2023. Among them, 44 cases developed API (API group), and 174 cases did not (control group). Levels of INS, Cort, Glu, and FBG were measured in both groups. Additionally, Abbreviated Injury Scale-Injury Severity Score (AIS-ISS) surveys and API severity assessments were conducted. Correlations between stress hormone levels and AIS-ISS were discussed. The predictive effects of AIS-ISS and stress hormones on API occurrence in trauma patients were analyzed using receiver operating characteristic (ROC) curves. The relationship between stress hormone levels and API severity was also observed. Results: Study's outcomes indicated distinct relationships between stress hormone levels and API occurrence in trauma patients. Specifically, INS demonstrated a negative correlation with AIS-ISS, highlighting its potential as a significant factor. Glu, Cort, and FBG revealed positive associations, emphasizing their roles in influencing API development (P < .05). The diagnostic efficacy of stress hormones in predicting API occurrence, as represented by the Area Under Curve (AUC) = 0.8100. Notably, within the API group, INS levels demonstrated a decline with worsening API. Conversely, Glu, Cort, and FBG exhibited increases in tandem with the aggravation of API symptoms (P < .05). Conclusions: This research suggests that assessing stress hormone levels in clinical settings can effectively predict API occurrence. Early testing could aid in the development of preventive or intervention measures, reducing the incidence and harm of API in trauma patients.

9.
Chem Biodivers ; 21(7): e202400832, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38712949

RESUMO

Two new cytochalasans, marcytoglobosins A (1) and B (2) were isolated from the marine sponge associated fungus Chaetomium globosum 162105, along with six known compounds (3-8). The complete structures of two new compounds were determined based on 1D/2D NMR and HR-MS spectroscopic analyses coupled with ECD calculations. All eight isolates were evaluated for their antibacterial activity. Among them, compounds 3-8 displayed antibacterial effects against Staphylococcus epidermidis, Bacillus thuringiensis, Pseudomonas syringae pv. Actinidiae, Vibrio alginolyticus, and Edwardsiella piscicida with minimum inhibitory concentration (MIC) values ranging from 10 to 25 µg/mL.


Assuntos
Antibacterianos , Chaetomium , Testes de Sensibilidade Microbiana , Poríferos , Chaetomium/química , Animais , Poríferos/microbiologia , Poríferos/química , Antibacterianos/farmacologia , Antibacterianos/química , Antibacterianos/isolamento & purificação , Citocalasinas/farmacologia , Citocalasinas/química , Citocalasinas/isolamento & purificação , Conformação Molecular
10.
J Wound Care ; 33(Sup2a): x-xiii, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38324424

RESUMO

Treatment of soft tissue wounds with bone or tendon exposure remains a tough clinical challenge for surgeons. The current clinical approaches include various types of flap reconstruction and artificial dermis grafting as well as negative pressure wound therapy (NPWT), which are time-consuming and often result in graft failure or significant scarring. Concentrated growth factor (CGF) is a novel blood extract that contains many growth factors, platelets and fibrin to promote an orderly healing process. However, few reports have focused on wounds with bone or tendon exposure. We present a limited series and two specific cases of skin wound with bone or tendon exposed that received surgical debridement followed by CGF treatment. CGF appeared to facilitate wound closure effectively and also reduced scar formation. Our findings provide a novel therapeutic option for refractory wounds with bone or tendon exposure.


Assuntos
Tratamento de Ferimentos com Pressão Negativa , Lesões dos Tecidos Moles , Humanos , Transplante de Pele , Cicatrização , Lesões dos Tecidos Moles/terapia , Cicatriz/cirurgia , Tendões/cirurgia , Peptídeos e Proteínas de Sinalização Intercelular/uso terapêutico , Resultado do Tratamento
11.
J Asian Nat Prod Res ; : 1-7, 2024 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-38945154

RESUMO

A new steroid, 2a-oxa-2-oxo-5ß-hydroxy-3,4-dinor-24-methylcholesta-22E-ene (1), together with 10 known ones (2-11), was isolated from the marine sponge Cliona sp. The structures of these compounds were determined by the spectroscopic methods (UV, IR, MS, and NMR) and X-ray diffraction analysis. Compound 1 was the third example of 3,4-dinorsteroid with a hemiketal at C-5 that was isolated from the natural source. In addition, the antibacterial activities of these compounds were also evaluated. However, none of them exhibited significant inhibition effects.

12.
J Asian Nat Prod Res ; 26(3): 328-333, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37602427

RESUMO

(+)- and (-)-Tedanine [(+)-1 and (-)-1], a pair of new enantiomeric indolone alkaloids, along with nine compounds (2-10) were isolated from the marine sponge Tedania sp. The structures of (+)-1 and (-)-1 including absolute configurations were determined by spectroscopic analysis and quantum chemical calculation. Compounds (+)-1 and (-)-1 were the first examples of indolone alkaloids isolated from this genus. In addition, the cytotoxic and antibacterial activities of these compounds were also evaluated.


Assuntos
Alcaloides , Antineoplásicos , Poríferos , Animais , Poríferos/química , Alcaloides/química , Antibacterianos/química , Antineoplásicos/química , Estrutura Molecular
13.
Molecules ; 29(2)2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38257331

RESUMO

Liver fibrosis is the initial pathological process of many chronic liver diseases. Targeting hepatic stellate cell (HSC) activation is an available strategy for the therapy of liver fibrosis. We aimed to explore the anti-liver fibrosis activity and potential mechanism of phomopsterone B (PB) in human HSCs. The results showed that PB effectively attenuated the proliferation of TGF-ß1-stimulated LX-2 cells in a concentration-dependent manner at doses of 1, 2, and 4 µM. Quantitative real-time PCR and Western blot assays displayed that PB significantly reduced the expression levels of α-SMA and collagen I/III. AO/EB and Hoechst33342 staining and flow cytometry assays exhibited that PB promoted the cells' apoptosis. Meanwhile, PB diminished the number of autophagic vesicles and vacuolated structures, and the LC3B fluorescent spots indicated that PB could effectively inhibit the accretion of autophagosomes in LX-2 cells. Moreover, rapamycin and MHY1485 were utilized to further investigate the effect of mTOR in autophagy and apoptosis. The results demonstrated that PB regulated autophagy and apoptosis via the mTOR-dependent pathway in LX-2 cells. In summary, this is the first evidence that PB effectively alleviates liver fibrosis in TGF-ß1-stimulated LX-2 cells, and PB may be a promising candidate for the prevention of liver fibrosis.


Assuntos
Autofagia , Fator de Crescimento Transformador beta1 , Humanos , Cirrose Hepática/tratamento farmacológico , Autofagossomos , Apoptose
14.
Zhongguo Zhong Yao Za Zhi ; 49(13): 3432-3440, 2024 Jul.
Artigo em Zh | MEDLINE | ID: mdl-39041115

RESUMO

Molecular pharmacognosy as an emerging interdisciplinary subject based on molecular biology and Chinese materia medica aims to study the synthesis and molecular regulation of secondary metabolites in medicinal plants. Andrographis Herba, the dried aboveground part of Andrographis paniculata, has liver-protecting, bile secretion-promoting, heat-clearing, toxin-removing, antimicrobial, and anti-inflammatory effects. The quality instability caused by plant varieties, environment, and technology in the production of A. paniculata is a limiting factor for the sustainable development of this industry. Based on the research methods of molecular pharmacognosy and omics, the regulation of secondary metabolites of A. paniculata has become the key solution to the quality problems of A. paniculata. This paper summarized the recent research achievements in the molecular pharmacognosy of A. paniculata, including molecular identification of the resources, genetic diversity, multi-omics, biosynthesis of active compounds, and germplasm resource innovation, and prospected the future development trend in this field. In-depth research of molecular pharmacognosy of A. paniculata will provide more scientific and effective technical support for the development of its medicinal value, give new insights into the cultivation of new A. paniculata varieties, and promote the high-quality sustainable development of this industry.


Assuntos
Farmacognosia , Andrographis/química , Andrographis/genética , Medicamentos de Ervas Chinesas/química , Plantas Medicinais/genética , Plantas Medicinais/química , Andrographis paniculata/genética , Andrographis paniculata/química , Andrographis paniculata/metabolismo
15.
Zhongguo Zhong Yao Za Zhi ; 49(2): 379-388, 2024 Jan.
Artigo em Zh | MEDLINE | ID: mdl-38403314

RESUMO

Andrographis paniculata is an important medicinal plant in the Lingnan region of China, which has the functions of clearing heat, removing toxins, and resisting bacteria and inflammation. The TCP gene family is a class of transcription factors that regulate plant growth, development, and stress response. In order to analysis the role of the TCP gene family under abiotic stress in A. paniculata, this study identified the TCP gene family of A. paniculata at the genome-wide level and analyzed its expression pattern in response to abiotic stress. The results showed that the A. paniculata TCP gene family had 23 members, with length of amino acid ranging from 136 to 508, the relative molecular mass between 14 854.71 and 55 944.90 kDa, and the isoelectric point between 5.67 and 10.39. All members were located in the nucleus and unevenly distributed on 13 chromosomes. Phylogenetic analysis classified them into three subfamilies: PCF, CIN and CYC/TB1. Gene structure and conserved motif analysis showed that most members of the TCP gene family contained motif 1, motif 2, motif 3 in the same order and 1-3 CDS. The analysis of promoter cis-acting elements showed that the transcriptional expression of the TCP gene family in A. paniculata might be induced by light, hormones, and adversity stress. In light of the expression pattern analysis and qRT-PCR verification, the expression of ApTCP4, ApTCP5, ApTCP6, and ApTCP11 involved in response by various abiotic stresses such as drought, high temperature, and MeJA. This study lays the foundation for in-depth exploration of the functions of A. paniculata TCP genes in response to abiotic stress.


Assuntos
Aminoácidos , Andrographis paniculata , Filogenia , China , Secas , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/genética
16.
J Am Chem Soc ; 145(1): 277-287, 2023 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-36548022

RESUMO

Redox signaling molecules include a number of reactive oxygen species (ROS), reactive nitrogen species (RNS), and reactive sulfur species (RSS). These molecules work collectively in the regulation of many physiological processes. Understanding the crosstalk mechanisms in these signaling molecules is important but challenging. The development of donor compounds of ROS/RNS/RSS will aid the advances in this field. While many donors that can release one ROS/RNS/RSS have been developed, dual donors that can release two signaling species and facilitate their crosstalk studies are still very rare. Those limited examples lack the ability to precisely control the timing of two releases. In this work, a 2-methoxy-6-naphthacyl-derived tertiary SNO compound, Naph-SNO, was designed and evaluated as the dual donor for NO and H2S2. The 2-methoxy-6-naphthacyl structure was demonstrated to be a novel photoremovable protecting group that could directly uncage C-S bonds. Under the irradiation of lights with different wavelengths (visible or UV), Naph-SNO could release NO and H2S2 in a stepwise manner, or simultaneously (i.e., likely producing the crosstalk product HSNO/HSSNO). In addition, the release of payloads from the donor also produced an end product with blue fluorescence. Therefore, the release process could be easily monitored in "real time." This controllable photo-triggered release strategy has the potential to be used in the design of other RNS/RSS dual donors.


Assuntos
Transdução de Sinais , Enxofre , Espécies Reativas de Oxigênio , Preparações de Ação Retardada , Oxirredução , Enxofre/química
17.
BMC Microbiol ; 23(1): 386, 2023 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-38053022

RESUMO

BACKGROUND: There is a link between Helicobacter pylori (HP) infection and small intestinal bacterial overgrowth (SIBO) with nonspecific digestive symptoms. Nonetheless, whether HP infection is associated with SIBO in adults remains unclear. Based on a meta-analysis, we evaluated this relationship. RESULTS: Observational studies relevant to our research were identified by searching PubMed, Embase, the Cochrane Library, and the Web of Science. We evaluated between-study heterogeneity using the Cochrane Q test and estimated the I2 statistic. Random-effects models were used when significant heterogeneity was observed; otherwise, fixed-effects models were used. Ten datasets from eight studies, including 874 patients, were involved in the meta-analysis. It was shown that HP infection was related to a higher odds of SIBO (odds ratio [OR]: 1.82, 95% confidence interval: 1.29 to 2.58, p < 0.001) with mild heterogeneity (p for Cochrane Q test = 0.11, I2 = 7%). Subgroup analyses showed that HP infection was related to SIBO in young patients (mean age < 48 years, OR: 2.68, 95% CI: 1.67 to 4.28, p < 0.001; I2 = 15%) but not in older patients (mean age ≥ 48 years, OR: 1.15, 95% CI: 0.69 to 1.92, p < 0.60; I2 = 1%; p for subgroup difference = 0.02). Subgroup analyses further indicated that the association was not significantly affected by the country of study, comorbidities, exposure to proton pump inhibitors, or methods of evaluating HP infection and SIBO. CONCLUSIONS: HP infection may be related to SIBO in adults, which supports the detection of SIBO in patients with digestive symptoms and HP infection.


Assuntos
Infecções por Helicobacter , Helicobacter pylori , Adulto , Humanos , Pessoa de Meia-Idade , Intestino Delgado/microbiologia , Inibidores da Bomba de Prótons
18.
Opt Lett ; 48(15): 4033-4036, 2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-37527111

RESUMO

Metal plasmonic nano-gratings possess a high absorption ability and exhibit potential applications in sensing, hot-electron photodetection, metasurfaces, etc. However, the fabrication techniques of high-quality nano-gratings are challenging. In this article, a binary metal micron grating for near-infrared hot-electron photodetectors (HEPDs) is designed in which the surface plasmons are excited by high-diffraction-order modes. The high-diffraction-order micron grating can be fabricated by conventional lithography and has a significantly higher tolerance in the grating parameters than a nano-grating. The range of absorption greater than 70% is ∼3 times that of a nano-grating. Moreover, an interesting relationship between the resonant wavelength and the grating duty cycle is found. When the high-diffraction-order micron grating is applied in metal-insulator-metal HEPDs, a high zero-biased responsivity of 0.533 mA/W is achieved.

19.
Eur Radiol ; 33(12): 8899-8911, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37470825

RESUMO

OBJECTIVE: This study aimed to evaluate the diagnostic performance of machine learning (ML)-based ultrasound (US) radiomics models for risk stratification of gallbladder (GB) masses. METHODS: We prospectively examined 640 pathologically confirmed GB masses obtained from 640 patients between August 2019 and October 2022 at four institutions. Radiomics features were extracted from grayscale US images and germane features were selected. Subsequently, 11 ML algorithms were separately used with the selected features to construct optimum US radiomics models for risk stratification of the GB masses. Furthermore, we compared the diagnostic performance of these models with the conventional US and contrast-enhanced US (CEUS) models. RESULTS: The optimal XGBoost-based US radiomics model for discriminating neoplastic from non-neoplastic GB lesions showed higher diagnostic performance in terms of areas under the curves (AUCs) than the conventional US model (0.822-0.853 vs. 0.642-0.706, p < 0.05) and potentially decreased unnecessary cholecystectomy rate in a speculative comparison with performing cholecystectomy for lesions sized over 10 mm (2.7-13.8% vs. 53.6-64.9%, p < 0.05) in the validation and test sets. The AUCs of the XGBoost-based US radiomics model for discriminating carcinomas from benign GB lesions were higher than the conventional US model (0.904-0.979 vs. 0.706-0.766, p < 0.05). The XGBoost-US radiomics model performed better than the CEUS model in discriminating GB carcinomas (AUC: 0.995 vs. 0.902, p = 0.011). CONCLUSIONS: The proposed ML-based US radiomics models possess the potential capacity for risk stratification of GB masses and may reduce the unnecessary cholecystectomy rate and use of CEUS. CLINICAL RELEVANCE STATEMENT: The machine learning-based ultrasound radiomics models have potential for risk stratification of gallbladder masses and may potentially reduce unnecessary cholecystectomies. KEY POINTS: • The XGBoost-based US radiomics models are useful for the risk stratification of GB masses. • The XGBoost-based US radiomics model is superior to the conventional US model for discriminating neoplastic from non-neoplastic GB lesions and may potentially decrease unnecessary cholecystectomy rate for lesions sized over 10 mm in comparison with the current consensus guideline. • The XGBoost-based US radiomics model could overmatch CEUS model in discriminating GB carcinomas from benign GB lesions.


Assuntos
Carcinoma , Doenças da Vesícula Biliar , Neoplasias da Vesícula Biliar , Humanos , Estudos Prospectivos , Meios de Contraste , Neoplasias da Vesícula Biliar/diagnóstico por imagem , Aprendizado de Máquina , Medição de Risco , Estudos Retrospectivos
20.
J Org Chem ; 88(13): 7998-8009, 2023 07 07.
Artigo em Inglês | MEDLINE | ID: mdl-37279456

RESUMO

An unexpected Ugi cascade reaction was developed for the facile construction of γ-lactam-fused pyridone derivatives with high tolerance of substrates. A C(sp3)-N bond and a C(sp2)-C(sp2) bond were formed together, accompanied by a chromone ring-opening in Ugi adducts, under the basic conditions without any metal catalyst for the whole process. Screening data of several difficult-to-inhibit cancer cell lines demonstrated that 7l displayed a high cytotoxicity against HCT116 cells (IC50 = 5.59 ± 0.78 µM). Taken together, our findings revealed new insights into the molecular mechanisms underlying compound 7l and provided potential usage of this scaffold for cancer therapeutics.


Assuntos
Compostos Heterocíclicos , Lactamas , Lactamas/farmacologia , Piridonas/farmacologia , Piridonas/química , Metais
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