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1.
Small ; 20(24): e2310529, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38148294

RESUMO

2D organic-inorganic hybrid perovskites (OIHPs) have become one of the hottest research topics due to their excellent environmental stability and unique optoelectronic properties. Recently, the ferroelectricity and thermochromism of 2D OIHPs have attracted increasing interests. Integrating ferroelectricity and thermochromism into perovskites can significantly promote the development of multichannel intelligent devices. Here, a novel 2D Dion-Jacobson OIHP of the formula (3AMP)PbI4 (where 3AMP is 3-(aminomethyl)pyridinium) is reported, which has a remarkable spontaneous polarization value (Ps) of 15.6 µC cm-2 and interesting thermochromism. As far it is known, such a large Ps value is the highest for 2D OIHPs recorded so far. These findings will inspire further exploration and application of multifunctional perovskites.

2.
Artigo em Inglês | MEDLINE | ID: mdl-39312295

RESUMO

One bacterial strain, designated as C22-A2T, was isolated from Lake LungmuCo in Tibet. Cells of strain C22-A2T were long rod-shaped, Gram-stain-negative, non-spore-forming, with positive catalase and oxidase activity. Optimal growth occurred at 20-25 °C, pH 8.0 and with 3.0-7.0% (w/v) NaCl. Phylogenetic analysis of 16S rRNA gene and whole genome sequences revealed that strain C22-A2T belonged to the genus Virgibacillus, showing the highest 16S rRNA gene similarity to Virgibacillus halodenitrificans DSM 10037T (97.6%). The average nucleotide identity values between strain C22-A2T and the type strains of related species in the genus Virgibacillus were less than 74.4% and the digital DNA-DNA hybridization values were less than 20.2%, both below the species delineation thresholds of 95 and 70% respectively. The genome analysis revealed that strain C22-A2T harboured genes responsible for osmotic and oxidative stress, enabling it to adapt to its surrounding environment. In terms of biochemical and physiological characteristics, strain C22-A2T shared similar characteristics with the genus Virgibacillus, including the predominant cellular fatty acid anteiso-C15 : 0, the major respiratory quinone MK-7, as well as the polar lipids phosphatidylglycerol and diphosphatidylglycerol. Based on the comprehensive analysis of phylogenetic, phylogenomic, morphological, physiological and biochemical characteristics, strain C22-A2T is proposed to represent a novel species of the genus Virgibacillus, named as Virgibacillus tibetensis sp. nov. (=CGMCC 1.19202T=KCTC 43426T).


Assuntos
Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano , Ácidos Graxos , Lagos , Hibridização de Ácido Nucleico , Filogenia , RNA Ribossômico 16S , Análise de Sequência de DNA , Virgibacillus , Tibet , RNA Ribossômico 16S/genética , Lagos/microbiologia , DNA Bacteriano/genética , Virgibacillus/genética , Virgibacillus/isolamento & purificação , Virgibacillus/classificação , Cloreto de Sódio/metabolismo , Vitamina K 2/análogos & derivados , Vitamina K 2/análise , Genoma Bacteriano , Fosfolipídeos/análise , Sequenciamento Completo do Genoma
3.
Surg Endosc ; 38(1): 179-185, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37950029

RESUMO

BACKGROUND: Penile carcinoma is an uncommon cancer that develops in the penis tissue. The standard surgical method to manage regional lymph nodes after local excision is radical inguinal lymphadenectomy, but it has a high rate of complications. The objective of this retrospective study was to compare the long-term outcomes of endoscopic inguinal lymphadenectomy and open inguinal lymphadenectomy in patients with penile carcinoma. METHODS: The study included patients diagnosed with penile carcinoma who underwent open inguinal lymphadenectomy (n = 23) or endoscopic inguinal lymphadenectomy (n = 27) at a single hospital between January 2013 and January 2021. Operation time, blood loss, drainage, hospital stay, postoperative complications, and survival rates were assessed and compared between the two groups. RESULTS: The two groups were comparable in terms of age, tumor size and stage, inguinal lymph nodes, and follow-up. The endoscopic group had significantly lower blood loss (27.1 ± 1.5 ml vs 55.0 ± 2.7 ml, P < 0.05), shorter drainage time and hospital stay (4.7 ± 1.1 days vs 8.1 ± 2.2 days, and 13.4 ± 1.0 days vs 19 ± 2.0 days, respectively, P < 0.05), and longer operation time compared to the open group (82.2 ± 4.3 min in endoscopic group vs 53.1 ± 2.2 min in open group, P < 0.05). There were significant differences in the incidence of incisional infection, necrosis, and lymphorrhagia in both groups (4 vs 0, 4 vs 0, and 2 vs 0, respectively, P < 0.05). The inguinal lymph node harvested was comparable between the two groups. The mean follow-up time was similar for both groups (60.4 ± 7.7 m vs 59.8 ± 7.3 m), and the recurrence mortality rates were not significantly different. CONCLUSIONS: The study shows that both open and endoscopic methods work well for controlling penile carcinoma in the long term. But the endoscopic approach is better because it has fewer severe complications. So, the choice of surgery method might depend on factors like the surgeon's experience, what they like, and what resources are available.


Assuntos
Carcinoma , Neoplasias Penianas , Masculino , Humanos , Seguimentos , Estudos Retrospectivos , Cirurgia Vídeoassistida/métodos , Canal Inguinal , Excisão de Linfonodo/métodos , Neoplasias Penianas/cirurgia , Neoplasias Penianas/patologia , Carcinoma/cirurgia
4.
Acta Derm Venereol ; 104: adv24050, 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38932592

RESUMO

To examine the prevalence of comorbidities in Chinese urticaria patients and assess medication use patterns across different ages (6-11 years, 12-17 years, above 18 years), a retrospective cohort study was performed in 192,647 urticaria patients within the Health Database. After 1:1 propensity score matching, 166,921 people were divided into the urticaria group and the control group, and the follow-up data were collected within 2 years. During the 12-month and 24-month follow-up period, significant comorbidities identified included allergic rhinitis and asthma, with distinct patterns observed across age groups. Chronic urticaria patients often have complications, such as allergic rhinitis, upper respiratory infection, oropharyngeal infection, and dental caries. The study underscores the need for age-specific treatment strategies in urticaria management.


Assuntos
Urticária Crônica , Comorbidade , Humanos , Estudos Retrospectivos , Criança , Masculino , Adolescente , Feminino , China/epidemiologia , Prevalência , Fatores Etários , Adulto Jovem , Urticária Crônica/epidemiologia , Urticária Crônica/tratamento farmacológico , Adulto , Rinite Alérgica/epidemiologia , Fatores de Tempo , Urticária/epidemiologia , Urticária/diagnóstico , Fatores de Risco , Pontuação de Propensão , Pessoa de Meia-Idade , Bases de Dados Factuais , Asma/epidemiologia , Asma/tratamento farmacológico , Asma/diagnóstico , População do Leste Asiático
5.
Molecules ; 29(13)2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-38999013

RESUMO

Propane dehydrogenation (PDH) is a crucial approach for propylene production. However, commonly used CrOx-based catalysts have issues including easy sintering at elevated reaction temperatures and relying on high acidity supports. In this work, we develop a strategy, to strongly anchor and isolate active sites against their commonly observed aggregation during reactions, by taking advantage of the net trap effect in chromate intercalated Zn-Cr layered hydroxides as precursors. Furthermore, the intercalated chromate overcomes the collapse of traditional layered hydroxides during their transformation to metal oxide, thus exposing more available active sites. A joint fine modulation including crystal structure, surface acidity, specific surface area, and active sites dispersion is performed on the final mixed metal oxides for propane dehydrogenation. As a result, Zn1Cr2-CrO42--MMO delivers attractive propane conversion (~27%) and propylene selectivity (>90%) as compared to other non-noble-metal-based catalysts.

6.
Angew Chem Int Ed Engl ; 63(24): e202405493, 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38604975

RESUMO

Synthesis of ammonia by electrochemical nitrogen reduction reaction (NRR) is a promising alternative to the Haber-Bosch process. However, it is commonly obstructed by the high activation energy. Here, we report the design and synthesis of an Al-Al bonded dual atomic catalyst stabilized within an amorphous nitrogen-doped porous carbon matrix (Al2NC) with high NRR performance. The dual atomic Al2-sites act synergistically to catalyze the complex multiple steps of NRR through adsorption and activation, enhancing the proton-coupled electron transfer. This Al2NC catalyst exhibits a high Faradaic efficiency of 16.56±0.3 % with a yield rate of 29.22±1.2 µg h-1 mgcat -1. The dual atomic Al2NC catalyst shows long-term repeatable, and stable NRR performance. This work presents an insight into the identification of synergistic dual atomic catalytic site and mechanistic pathway for the electrochemical conversion of N2 to NH3.

7.
Angew Chem Int Ed Engl ; 63(27): e202320014, 2024 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-38598078

RESUMO

Amino acids are the building blocks of proteins and are widely used as important ingredients for other nitrogen-containing molecules. Here, we report the sustainable production of amino acids from biomass-derived hydroxy acids with high activity under visible-light irradiation and mild conditions, using atomic ruthenium-promoted cadmium sulfide (Ru1/CdS). On a metal basis, the optimized Ru1/CdS exhibits a maximal alanine formation rate of 26.0 molAla ⋅ gRu -1 ⋅ h-1, which is 1.7 times and more than two orders of magnitude higher than that of its nanoparticle counterpart and the conventional thermocatalytic process, respectively. Integrated spectroscopic analysis and density functional theory calculations attribute the high performance of Ru1/CdS to the facilitated charge separation and O-H bond dissociation of the α-hydroxy group, here of lactic acid. The operando nuclear magnetic resonance further infers a unique "double activation" mechanism of both the CH-OH and CH3-CH-OH structures in lactic acid, which significantly accelerates its photocatalytic amination toward alanine.


Assuntos
Aminoácidos , Biomassa , Compostos de Cádmio , Rutênio , Sulfetos , Sulfetos/química , Rutênio/química , Compostos de Cádmio/química , Catálise , Aminoácidos/química , Processos Fotoquímicos , Teoria da Densidade Funcional , Luz
8.
Mol Pharmacol ; 104(4): 133-143, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37419692

RESUMO

Licorice is a traditional Chinese medicine and recorded to have pain relief effects in national pharmacopoeia, but the mechanisms behind these effects have not been fully explored. Among the hundreds of compounds in licorice, licochalcone A (LCA) and licochalcone B (LCB) are two important components belonging to the chalcone family. In this study, we compared the analgesic effects of these two licochalcones and the molecular mechanisms. LCA and LCB were applied in cultured dorsal root ganglion (DRG) neurons, and the voltage-gated sodium (NaV) currents and action potentials were recorded. The electrophysiological experiments showed that LCA can inhibit NaV currents and dampen excitabilities of DRG neurons, whereas LCB did not show inhibition effect on NaV currents. Because the NaV1.7 channel can modulate Subthreshold membrane potential oscillations in DRG neuron, which can palliate neuropathic pain, HEK293T cells were transfected with NaV1.7 channel and recorded with whole-cell patch clamp. LCA can also inhibit NaV1.7 channels exogenously expressed in HEK293T cells. We further explored the analgesic effects of LCA and LCB on formalin-induced pain animal models. The animal behavior tests revealed that LCA can inhibit the pain responses during phase 1 and phase 2 of formalin test, and LCB can inhibit the pain responses during phase 2. The differences of the effects on NaV currents between LCA and LCB provide us with the basis for developing NaV channel inhibitors, and the novel findings of analgesic effects indicate that licochalcones can be developed into effective analgesic medicines. SIGNIFICANCE STATEMENT: This study found that licochalcone A (LCA) can inhibit voltage-gated sodium (NaV) currents, dampen excitabilities of dorsal root ganglion neurons, and inhibit the NaV1.7 channels exogenously expressed in HEK293T cells. Animal behavior tests showed that LCA can inhibit the pain responses during phase 1 and phase 2 of formalin test, whereas licochalcone B can inhibit the pain responses during phase 2. These findings indicate that licochalcones could be the leading compounds for developing NaV channel inhibitors and effective analgesic medicines.


Assuntos
Neuralgia , Canais de Sódio Disparados por Voltagem , Animais , Humanos , Bloqueadores dos Canais de Sódio/farmacologia , Células HEK293 , Gânglios Espinais , Sódio , Canal de Sódio Disparado por Voltagem NAV1.7
9.
J Biol Chem ; 298(1): 101457, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34861238

RESUMO

Toxin-antitoxin (TA) systems are ubiquitous regulatory modules for bacterial growth and cell survival following stress. YefM-YoeB, the most prevalent type II TA system, is present in a variety of bacterial species. In Staphylococcus aureus, the YefM-YoeB system exists as two independent paralogous copies. Our previous research resolved crystal structures of the two oligomeric states (heterotetramer and heterohexamer-DNA ternary complex) of the first paralog as well as the molecular mechanism of transcriptional autoregulation of this module. However, structural details reflecting molecular diversity in both paralogs have been relatively unexplored. To understand the molecular mechanism of how Sa2YoeB and Sa2YefM regulate their own transcription and how each paralog functions independently, we solved a series of crystal structures of the Sa2YoeB-Sa2YefM. Our structural and biochemical data demonstrated that both paralogous copies adopt similar mechanisms of transcriptional autoregulation. In addition, structural analysis suggested that molecular diversity between the two paralogs might be reflected in the interaction profile of YefM and YoeB and the recognition pattern of promoter DNA by YefM. Interaction analysis revealed unique conformational and activating force effected by the interface between Sa2YoeB and Sa2YefM. In addition, the recognition pattern analysis demonstrated that residues Thr7 and Tyr14 of Sa2YefM specifically recognizes the flanking sequences (G and C) of the promoter DNA. Together, these results provide the structural insights into the molecular diversity and independent function of the paralogous copies of the YoeB-YefM TA system.


Assuntos
Antitoxinas , Toxinas Bacterianas , DNA Bacteriano , Staphylococcus aureus , Sistemas Toxina-Antitoxina , Antitoxinas/química , Antitoxinas/metabolismo , Toxinas Bacterianas/química , Toxinas Bacterianas/metabolismo , DNA Bacteriano/metabolismo , Staphylococcus aureus/genética , Staphylococcus aureus/metabolismo
10.
Mol Med ; 29(1): 154, 2023 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-37936054

RESUMO

BACKGROUND: Tyrosine kinase and phosphoinositide kinase pathways play important roles in asthma formation. As a dual tyrosine and phosphoinositide kinase inhibitor, PP121 has shown anticancer efficacy in multiple tumors. However, the study of PP121 in pulmonary diseases is still limited. Herein, we investigated the therapeutic activities of PP121 in asthma treatment. METHODS: Tension measurements and patch clamp recordings were made to investigate the anticontractile characteristics of PP121 in vitro. Then, an asthma mouse model was established to further explore the therapeutic characteristics of PP121 via measurement of respiratory system resistance, histological analysis and western blotting. RESULTS: We discovered that PP121 could relax precontracted mouse tracheal rings (mTRs) by blocking certain ion channels, including L-type voltage-dependent Ca2+ channels (L-VDCCs), nonselective cation channels (NSCCs), transient receptor potential channels (TRPCs), Na+/Ca2+ exchangers (NCXs) and K+ channels, and accelerating calcium mobilization. Furthermore, PP121 relieved asthmatic pathological features, including airway hyperresponsiveness, systematic inflammation and mucus secretion, via downregulation of inflammatory factors, mucins and the mitogen-activated protein kinase (MAPK)/Akt signaling pathway in asthmatic mice. CONCLUSION: In summary, PP121 exerts dual anti-contractile and anti-inflammatory effects in asthma treatment, which suggests that PP121 might be a promising therapeutic compound and shed new light on asthma therapy.


Assuntos
Asma , Hipersensibilidade Respiratória , Animais , Camundongos , 1-Fosfatidilinositol 4-Quinase/metabolismo , Asma/tratamento farmacológico , Hipersensibilidade Respiratória/metabolismo , Inflamação/metabolismo , Muco/metabolismo , Modelos Animais de Doenças , Camundongos Endogâmicos BALB C , Ovalbumina
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