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1.
Gastroenterology ; 164(1): 89-102, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36113570

RESUMO

BACKGROUND & AIMS: Intestinal fibrosis is a significant complication of Crohn's disease (CD). Gut microbiota reactive Th17 cells are crucial in the pathogenesis of CD; however, how Th17 cells induce intestinal fibrosis is still not completely understood. METHODS: In this study, T-cell transfer model with wild-type (WT) and Areg-/- Th17 cells and dextran sulfate sodium (DSS)-induced chronic colitis model in WT and Areg-/- mice were used. CD4+ T-cell expression of AREG was determined by quantitative reverse-transcriptase polymerase chain reaction and enzyme-linked immunosorbent assay. The effect of AREG on proliferation/migration/collagen expression in human intestinal myofibroblasts was determined. AREG expression was assessed in healthy controls and patients with CD with or without intestinal fibrosis. RESULTS: Although Th1 and Th17 cells induced intestinal inflammation at similar levels when transferred into Tcrßxδ-/- mice, Th17 cells induced more severe intestinal fibrosis. Th17 cells expressed higher levels of AREG than Th1 cells. Areg-/- mice developed less severe intestinal fibrosis compared with WT mice on DSS insults. Transfer of Areg-/- Th17 cells induced less severe fibrosis in Tcrßxδ-/- mice compared with WT Th17 cells. Interleukin (IL)6 and IL21 promoted AREG expression in Th17 cells by activating Stat3. Stat3 inhibitor suppressed Th17-induced intestinal fibrosis. AREG promoted human intestinal myofibroblast proliferation, motility, and collagen I expression, which was mediated by activating mammalian target of rapamycin and MEK. AREG expression was increased in intestinal CD4+ T cells in fibrotic sites compared with nonfibrotic sites from patients with CD. CONCLUSIONS: These findings reveal that Th17-derived AREG promotes intestinal fibrotic responses in experimental colitis and human patients with CD. Thereby, AREG might serve as a potential therapeutic target for fibrosis in CD.


Assuntos
Colite , Doença de Crohn , Animais , Humanos , Camundongos , Anfirregulina/genética , Anfirregulina/metabolismo , Colite/metabolismo , Colágeno/metabolismo , Doença de Crohn/patologia , Sulfato de Dextrana/efeitos adversos , Fibrose , Mucosa Intestinal/patologia , Camundongos Endogâmicos C57BL , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo , Miofibroblastos/patologia , Células Th17/metabolismo , Serina-Treonina Quinases TOR/metabolismo
2.
J Virol ; 97(5): e0029223, 2023 05 31.
Artigo em Inglês | MEDLINE | ID: mdl-37133374

RESUMO

Chemokine production by epithelial cells is crucial for neutrophil recruitment to sites of inflammation during viral infection. However, the effect of chemokine on epithelia and how chemokine is involved in coronavirus infection remains to be fully understood. Here, we identified an inducible chemokine interleukin-8 (CXCL8/IL-8), which could promote coronavirus porcine epidemic diarrhea virus (PEDV) infection in African green monkey kidney epithelial cells (Vero) and Lilly Laboratories cell-porcine kidney 1 epithelial cells (LLC-PK1). IL-8 deletion restrained cytosolic calcium (Ca2+), whereas IL-8 stimulation improved cytosolic Ca2+. The consumption of Ca2+ restricted PEDV infection. PEDV internalization and budding were obvious reductions when cytosolic Ca2+ was abolished in the presence of Ca2+ chelators. Further study revealed that the upregulated cytosolic Ca2+ redistributes intracellular Ca2+. Finally, we identified that G protein-coupled receptor (GPCR)-phospholipase C (PLC)-inositol trisphosphate receptor (IP3R)-store-operated Ca2+ (SOC) signaling was crucial for enhancive cytosolic Ca2+ and PEDV infection. To our knowledge, this study is the first to uncover the function of chemokine IL-8 during coronavirus PEDV infection in epithelia. PEDV induces IL-8 expression to elevate cytosolic Ca2+, promoting its infection. Our findings reveal a novel role of IL-8 in PEDV infection and suggest that targeting IL-8 could be a new approach to controlling PEDV infection. IMPORTANCE Coronavirus porcine epidemic diarrhea virus (PEDV) is a highly contagious enteric coronavirus that caused severe economic losses worldwide, and more effort is needed to develop economical and efficient vaccines to control or eliminate this disease. The chemokine interleukin-8 (CXCL8/IL-8) is indispensable for the activation and trafficking of inflammatory mediators and tumor progression and metastasis. This study evaluated the effect of IL-8 on PEDV infection in epithelia. We found that IL-8 expression improved cytosolic Ca2+ in epithelia, facilitating PEDV rapid internalization and egress. G protein-coupled receptor (GPCR)-phospholipase C (PLC)-inositol trisphosphate receptor (IP3R)-SOC signaling was activated by IL-8, releasing the intracellular Ca2+ stores from endoplasmic reticulum (ER). These findings provide a better understanding of the role of IL-8 in PEDV-induced immune responses, which will help develop small-molecule drugs for coronavirus cure.


Assuntos
Infecções por Coronavirus , Coronavirus , Vírus da Diarreia Epidêmica Suína , Doenças dos Suínos , Animais , Quimiocinas , Chlorocebus aethiops , Interleucina-8 , Vírus da Diarreia Epidêmica Suína/fisiologia , Suínos , Células Vero , Replicação Viral
3.
Chemistry ; 30(34): e202401008, 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38624085

RESUMO

Here we report B(C6F5)3/CPA-catalyzed enantioselective aza-Diels-Alder reaction of 3,3-difluoro-2-Aryl-3H-indoles with unactivated dienes to access chiral 10,10-difluoro-tetrahydropyrido[1,2-a]indoles. This protocol allows the formation of pyrazole-based C2-quaternary indolin-3-ones with high enantioselectivities and regioselectivities. Moreover, gram-scale synthesis of the 10,10-difluoro-tetrahydropyrido[1,2-a]indole skeleton was successfully achieved without any reduction in both yield and enantioselectivity.

4.
Chemistry ; : e202402843, 2024 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-39304988

RESUMO

The utilization of axially chiral biaryl diamines has been widely acknowledged as highly advantageous structures for the advancement of chiral catalysts and ligands. This highlights their extensive range of applications in asymmetric catalysis and synthesis. Herein, we devised a direct arylation reactions of 5-aminopyrazoles with azonaphthalenes, utilizing chiral phosphoric acid as the catalyst. This method delivers structurally novel atroposelective N, N-1,2-azole heteroaryl diamines with high yields (up to >98%) and good to excellent enantiomeric ratios while exhibiting a wide range of substrate compatibility.

5.
Langmuir ; 40(33): 17807-17814, 2024 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-39102744

RESUMO

In this study, BiVO4 nanosheets (BiVO4-NS) were prepared by a facile hydrothermal method. It is found that sonication-induced strain can effectively promote the H2 production over BiVO4-NS in the presence of pure water without any cocatalysts. With the assistance of the sonication, the H2 production over BiVO4-NS is 1.344 mmol·g-1 after 3 h simulated sunlight irradiation, which is 24.8 times higher than that of BiVO4-NS without sonication (0.054 mmol·g-1). In addition, the products of water oxidation are determined to be hydroxyl radicals and hydrogen peroxide. Moreover, BiVO4-NS also shows obviously enhanced photoactivity than that of the commercially available BiVO4 nanoparticles (BiVO4-C). The improved photoactivity of BiVO4-NS is attributed to the effective charge separation and low charge transfer resistance. The underlying mechanism of sonication-promoted water splitting is investigated by a variety of controlled experiments. The results show that ultrasonic waves can produce obvious strain inside the sample, which results in lattice distortion of BiVO4. Therefore, the conduction band of BiVO4 is obviously negative shifted, which is beneficial for H2 production. In addition, the strain in BiVO4 also produces local polarization of the sample, which effectively promotes the charge transfer and separation process. It is hoped that our study could provide a new strategy for achieving efficient photocatalytic water splitting.

6.
J Org Chem ; 89(18): 13071-13076, 2024 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-39254633

RESUMO

A novel electrocatalytic dimerization of o-aminphenols and a hydrogen borrowing-like cascade for synthesizing N-monoalkylated aminophenoxazinones have been developed. This electrocatalytic reaction uses a constant current mode in an undivided cell and is free of metal catalysis, open to the air, and eco-friendly. In particular, this protocol exhibits a wide substrate range and provides versatile N-monoalkylated aminophenoxazinones in medium to good yields. The results of our mechanistic research reveal that this protocol involves a cascade of electrochemical cyclocondensation of o-aminphenols and the hydrogen transfer process via paired electrolysis.

7.
Inorg Chem ; 63(38): 17672-17680, 2024 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-39259024

RESUMO

Cluster-assembled nanowires provide a unique strategy for the preparation of high-performance nanostructures. However, existing preparations are limited by complex processes and harsh reaction conditions. Here, Ag+ ions were utilized as a novel structure-directing agent to generate the self-assembly of Pt clusters to form ultrafine nanowires with a diameter of less than 5 nm. Electrospray ionization mass spectrometry (ESI-MS) and extended X-ray absorption fine structure (EXAFS) characterizations demonstrated that every Ag+ bridged two [Pt3(CO)3(µ2-CO)3]n2- clusters through coordination and formed a sandwich-like structure of [Pt3(CO)3(µ2-CO)3]nAg[Pt3(CO)3(µ2-CO)3]m3-. As a result, multiple sandwich-like structures of [Pt3(CO)3(µ2-CO)3]nAg[Pt3(CO)3(µ2-CO)3]m3- were established by Ag+ to form Pt nanowire superstructures {[Pt3(CO)6]nAg[Pt3(CO)6]mAg[Pt3(CO)6]x}∞ (abbreviated as Ag-Pt NWS). Our results demonstrate that the Pt nanowire superstructures showed promising cocatalytic performance for photocatalytic H2 production with the involvement of Ag+, which promises a desirable way to develop advanced functional nanomaterials.

8.
Gynecol Endocrinol ; 40(1): 2382818, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-39039858

RESUMO

Premature ovarian insufficiency (POI) or premature ovarian failure (POF) is a multifactorial disorder occurring in reproductive-age women, characterized by elevated levels of follicle-stimulating hormone (FSH) and irregular or absent menstrual cycles, often accompanied by perimenopausal symptoms and infertility. While assisted reproductive technology can address the reproductive aspirations of some POI-affected women, it is hindered by issues such as exorbitant expenses, substantial risks, and poor rates of conception. Encouragingly, extensive research is exploring novel approaches to enhance fertility, particularly in the realm of stem cell therapy, showcasing both feasibility and significant potential. Human amniotic epithelial cells (hAECs) from discarded placental tissues are crucial in regenerative medicine for their pluripotency, low immunogenicity, non-tumorigenicity, accessibility, and minimal ethical concerns. Preclinical studies highlight the underlying mechanisms and therapeutic effects of hAECs in POI treatment, and current research is focusing on innovative interventions to augment hAECs' efficacy. However, despite these strides, overcoming application challenges is essential for successful clinical translation. This paper conducted a comprehensive analysis of the aforementioned issues, examining the prospects and challenges of hAECs in POI, with the aim of providing some insights for future research and clinical practice.


Assuntos
Âmnio , Células Epiteliais , Insuficiência Ovariana Primária , Humanos , Insuficiência Ovariana Primária/terapia , Feminino , Células Epiteliais/transplante , Âmnio/citologia , Âmnio/transplante
9.
Syst Parasitol ; 101(6): 68, 2024 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-39436548

RESUMO

A new species, Myxobolus liuyangensis sp. n., was found in the gills of the exotic mrigal carp Cirrhinus mrigala during a survey of the fauna of exotic fish myxospore in China. Plasmodia were elongated pyriform, measuring 0.42 mm long and 0.15 mm wide. The mature spores were elongated pyriform in the frontal view, tapered forward, rounded posterior end, and fusiform in the sutural view, measuring 17.3 ±0.5 (16.5-18.3) µm long, 6.2 ±0.3 (5.2-6.8) µm wide, and 4.8 ±0.2 (4.4-5.1) µm thick. The two equal polar capsules of elongated pyriform in shape measured 11.3 ±0.5 (10.6-12.3) µm long and 2.5 ±0.3 (2.0-3.1) µm wide, occupying more than half the capacity of the spores. The polar filaments were coiled with fifteen to sixteen turns. No mucous envelope and caudal appendages were found. The consensus SSU rDNA gene sequence obtained here for M. liuyangensis sp. n. did not match any sequences available in GenBank, but was most closely related to M. catlae that infects the gills of C. cirrhosis (MT003664, 97.99% similarity). Phylogenetic analysis indicated that the C. mrigala-infecting Myxobolus species were not clustered together, but dispersed in different clades. The present species clustered with M. catlae and M. orissae within the clade I of elongated pyriform spore shapes, revealing spore shapes may play an important role during the evolution of Myxobolus species. This is the second myxosporean infection report in the exotic mrigal carp C. mrigala.


Assuntos
Brânquias , Myxobolus , Filogenia , Especificidade da Espécie , Animais , Brânquias/parasitologia , Myxobolus/classificação , Myxobolus/genética , Myxobolus/anatomia & histologia , Myxobolus/citologia , China , Carpas/parasitologia , Doenças dos Peixes/parasitologia
10.
Mil Psychol ; 36(2): 148-157, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38377245

RESUMO

This study constructed a moderated mediation model to examine whether increased army morale could reduce suicidal ideation. The mediating role of grit and the moderating role of social support were also examined. A total of 1029 male navy cadets in China were recruited to complete the survey. The measures used in the study included the Army Morale Scale, Grit Scale, Social Support Scale, and Self-rated Idea of Suicide Scale. The results indicated that: increased army morale could significantly reduce suicidal ideation; the impact of army morale on suicidal ideation could be partially mediated by grit; and social support moderated the impact of army morale on suicidal ideation. Specifically, relatively higher levels of social support could reduce suicidal ideation among individuals with lower levels of army morale, but the effect is not significant when the morale is at a high level. The study revealed that increased army morale could reduce suicidal ideation. Moreover, the mediating role of grit and the moderating role of social support were also revealed.


Assuntos
Ideação Suicida , Suicídio , Humanos , Masculino , Moral , Apoio Social , China
11.
Gastroenterology ; 162(1): 150-165, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34536451

RESUMO

BACKGROUND & AIMS: G protein-coupled receptor (GPR) 120 has been implicated in regulating metabolic syndromes with anti-inflammatory function. However, the role of GPR120 in intestinal inflammation is unknown. Here, we investigated whether and how GPR120 regulates CD4+ T cell function to inhibit colitis development. METHODS: Dextran sodium sulfate (DSS)-induced colitis model, Citrobacter rodentium infection model, and CD4+ T cell adoptive transfer model were used to analyze the role of GPR120 in regulating colitis development. The effect of GPR120 on CD4+ T cell functions was analyzed by RNA sequencing, flow cytometry, and Seahorse metabolic assays. Mice were administered GPR120 agonist for investigating the potential of GPR120 agonist in preventing and treating colitis. RESULTS: Deficiency of GPR120 in CD4+ T cells resulted in more severe colitis in mice upon dextran sodium sulfate insult and enteric infection. Transfer of GPR120-deficient CD4+CD45Rbhi T cells induced more severe colitis in Rag-/- mice with lower intestinal interleukin (IL) 10+CD4+ T cells. Treatment with the GPR120 agonist CpdA promoted CD4+ T cell production of IL10 by up-regulating Blimp1 and enhancing glycolysis, which was regulated by mTOR. GPR120 agonist-treated wild-type, but not IL10-deficient and Blimp1-deficient, T helper 1 cells induced less severe colitis. Furthermore, oral administration of GPR120 agonist protected mice from intestinal inflammation in both prevention and treatment schemes. Gpr120 expression was positively correlated with Il10 expression in the human colonic mucosa, including patients with inflammatory bowel diseases. CONCLUSIONS: Our findings show the role of GPR120 in regulating intestinal CD4+ T cell production of IL10 to inhibit colitis development, which identifies GPR120 as a potential therapeutic target for treating inflammatory bowel diseases.


Assuntos
Acetatos/farmacologia , Anti-Inflamatórios não Esteroides/farmacologia , Linfócitos T CD4-Positivos/efeitos dos fármacos , Colite/prevenção & controle , Colo/efeitos dos fármacos , Interleucina-10/metabolismo , Receptores Acoplados a Proteínas G/agonistas , Tiramina/análogos & derivados , Transferência Adotiva , Animais , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD4-Positivos/transplante , Estudos de Casos e Controles , Colite/imunologia , Colite/metabolismo , Colite Ulcerativa/imunologia , Colite Ulcerativa/metabolismo , Colo/imunologia , Colo/metabolismo , Doença de Crohn/imunologia , Doença de Crohn/metabolismo , Modelos Animais de Doenças , Glicólise/efeitos dos fármacos , Interleucina-10/genética , Camundongos Endogâmicos C57BL , Camundongos Knockout , Receptores Acoplados a Proteínas G/genética , Receptores Acoplados a Proteínas G/metabolismo , Transdução de Sinais , Tiramina/farmacologia
12.
Chemistry ; 29(20): e202203914, 2023 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-36600107

RESUMO

A chiral phosphoric acid-catalyzed enantioselective aza-Friedel-Crafts reaction of 5-aminopyrazole derivatives with cyclic ketimines attached to a neutral functional group is reported. This protocol allows the formation of pyrazole-based C2-quaternary indolin-3-ones with high enantioselectivities and regioselectivities. Moreover, gram-scale synthesis of the 5-aminopyrazole-based C2-quaternary indolin-3-ones was performed, with no decrease in the yield and enantioselectivity.

13.
Exp Eye Res ; 231: 109466, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37059215

RESUMO

Corneal alkali burn (AB) is a blindness-causing ocular trauma commonly seen in clinics. An excessive inflammatory reaction and stromal collagen degradation contribute to corneal pathological damage. Luteolin (LUT) has been studied for its anti-inflammatory effects. In this study, the effect of LUT on cornea stromal collagen degradation and inflammatory damage in rats with corneal alkali burn was investigated. After corneal alkali burn, rats were randomly assigned to the AB group and AB + LUT group and received an injection of saline and LUT (200 mg/kg) once daily. Subsequently, corneal opacity, epithelial defects, inflammation and neovascularization (NV) were observed and recorded on Days 1, 2, 3, 7 and 14 post-injury. The concentration of LUT in ocular surface tissues and anterior chamber, as well as the levels of collagen degradation, inflammatory cytokines, matrix metalloproteinases (MMPs) and their activity in the cornea were detected. Human corneal fibroblasts (HCFs) were co-cultured with interleukin (IL)-1ß and LUT. Cell proliferation and apoptosis were assessed by CCK-8 assay and flow cytometry respectively. Measurement of hydroxyproline (HYP) in culture supernatants was used to quantify the amount of collagen degradation. Plasmin activity was also assessed. ELISA or real-time PCR was used to detect the production of matrix metalloproteinases (MMPs), IL-8, IL-6 and monocyte chemotactic protein (MCP)-1. Furthermore, the immunoblot method was used to assess the phosphorylation of mitogen-activated protein kinases (MAPKs), transforming growth factor-ß-activated kinase (TAK)-1, activator protein-1 (AP-1) and inhibitory protein IκB-α. At last, immunofluorescence staining helped to develop nuclear factor (NF)-κB. LUT was detectable in ocular tissues and anterior chamber after intraperitoneal injection. An intraperitoneal injection of LUT ameliorated alkali burn-elicited corneal opacity, corneal epithelial defects, collagen degradation, NV, and the infiltration of inflammatory cells. The mRNA expressions of IL-1ß, IL-6, MCP-1, vascular endothelial growth factor (VEGF)-A, and MMPs in corneal tissue were downregulated by LUT intervention. And its administration reduced the protein levels of IL-1ß, collagenases, and MMP activity. Furthermore, in vitro study showed that LUT inhibited IL-1ß-induced type I collagen degradation and the release of inflammatory cytokines and chemokines by corneal stromal fibroblasts. LUT also inhibited the IL-1ß-induced activation of TAK-1, mitogen-activated protein kinase (MAPK), c-Jun, and NF-κB signaling pathways in these cells. Our results demonstrate that LUT inhibited alkali burn-stimulated collagen breakdown and corneal inflammation, most likely by attenuating the IL-1ß signaling pathway. LUT may therefore prove to be of clinical value for treating corneal alkali burns.


Assuntos
Queimaduras Químicas , Opacidade da Córnea , Ratos , Humanos , Animais , Queimaduras Químicas/complicações , Queimaduras Químicas/tratamento farmacológico , Queimaduras Químicas/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo , Luteolina/farmacologia , Luteolina/uso terapêutico , Álcalis/toxicidade , Interleucina-6/metabolismo , Córnea/metabolismo , Citocinas/metabolismo , Neovascularização Patológica/metabolismo , Colágeno Tipo I/metabolismo , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Opacidade da Córnea/metabolismo , Inflamação/metabolismo , Metaloproteinases da Matriz/metabolismo
14.
J Org Chem ; 88(11): 6599-6610, 2023 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-37157120

RESUMO

The enantioselective aza-MBH reaction is an efficient strategy for constructing novel carbon-carbon bonds, providing access to multitudinous chiral densely functionalized MBH products. However, the enantioselective aza-MBH reaction of cyclic-ketimines that would generate a versatile synthon is still missing and challenging. Herein, we developed a challenging direct organocatalytic asymmetric aza-MBH reaction involving cyclic ketimines attached to a neutral functional group. Moreover, the α,ß-unsaturated γ-butyrolactam was utilized as a rare nucleophile alkene in this work. The reactions provide enantiomerically enriched 2-alkenyl-2-phenyl-1,2-dihydro-3H-indol-3-ones, bearing with a tetra-substituted stereogenic center. Moreover, this reaction features high α-selectivities, high enantioselectivities (up to 99% ee), and good yields (up to 80%).

15.
Org Biomol Chem ; 21(3): 489-493, 2023 01 18.
Artigo em Inglês | MEDLINE | ID: mdl-36541043

RESUMO

The enantioselective aza-Friedel-Crafts reaction is one of the most straightforward and efficient strategies for constructing a new carbon-carbon bond bearing quaternary stereocenter in organic synthesis, but the catalytic asymmetric aza-Friedel-Crafts reaction of naphthols/phenols with cyclic-ketimines attached to a neutral functional group remains still relatively unexplored. Herein, a highly enantioselective aza-Friedel-Crafts reaction of cyclic-ketimines and naphthols/phenols has been realized using a chiral phosphoric acid catalyst. A variety of chiral aminonaphthols (chiral indolin-3-ones) containing a quaternary stereocenter at the C2 position were obtained with excellent outcomes (up to 97% yield, 98% ee). Moreover, the synthetic utility of the enantiomerically enriched chiral aminonaphthols was demonstrated in some efficient transformations. According to the experimental results, a possible transition state model has been proposed to rationalize the origin of asymmetric induction.


Assuntos
Naftóis , Fenóis , Naftóis/química , Fenóis/química , Elétrons , Estereoisomerismo , Estrutura Molecular , Catálise
16.
Org Biomol Chem ; 21(21): 4393-4397, 2023 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-37161837

RESUMO

The ß-C-H functionalization of amines is one of the most powerful tools for the synthesis of saturated nitrogen-containing heterocycles in organic synthesis. However, the ß-C-H functionalization of amines via redox-neutral addition with cyclic-ketimines is still unprecedented. Herein, the ß-C-H functionalization of tertiary amines is described, providing the corresponding 1,3-diamines containing the indolin-3-one moiety in high yields via the B(C6F5)3-catalyzed borrowing hydrogen strategy. According to the experimental results, a possible catalytic cycle has been proposed to rationalize the process of this reaction. Notably, the ß-C-H alkylation of amines is external oxidant- and transition-metal-free, which makes a significant contribution to promoting economical chemical synthesis.

17.
Phys Chem Chem Phys ; 25(44): 30663-30669, 2023 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-37933587

RESUMO

MnO2 is an oxide with many crystalline phases and is often used as a cathode material for aqueous zinc-ion batteries. However, its poor electrical conductivity and structural instability limit its further application. In the present work, Mo-doped MnO2 microflowers are successfully prepared by a facile hydrothermal method. Interestingly, it is found that the doping of Mo inhibits the phase transition from δ-MnO2 to α-MnO2, which may be related to the low crystallinity of Mo doped MnO2. Compared with undoped MnO2, Mo-doped MnO2 maintains two-dimensional morphology with a large specific surface area and mesoporous structure. In addition, the electronic conductivity and reversibility of Zn2+ insertion/extraction are improved in Mo doped MnO2. Therefore, Mo-doped MnO2 exhibits high reversible capacity and long cycling stability. For example, a high reversible capacity of 72.6 mA h g-1 can be achieved at a current density of 2000 mA g-1 after 2500 cycles.

18.
Pain Med ; 24(4): 415-424, 2023 04 03.
Artigo em Inglês | MEDLINE | ID: mdl-36124961

RESUMO

OBJECTIVE: To explore the clinical value of ultrasound guidance combined with C-arm guidance during selective semilunar ganglion radiofrequency thermocoagulation via the foramen ovale for trigeminal neuralgia. METHODS: This study enrolled 48 patients diagnosed with trigeminal neuralgia between January 2021 and December 2021 in the Department of Pain Management at Xuanwu Hospital. Patients were randomly and equally divided into a C-arm-only group and an ultrasound-combined-with-C-arm (ultrasound+C-arm) group, according to a random number table. After exclusions, 42 patients were analyzed. Of these, 21 patients underwent selective semilunar ganglion radiofrequency thermocoagulation via the foramen ovale guided by the C-arm alone, whereas 21 patients underwent the same procedure guided by ultrasound combined with C-arm. The number of punctures, the amount of time elapsed until the target area of the semilunar ganglion was punctured, the cumulative dose of radiation exposure, and puncture-related complications were recorded during the operation. Numerical rating scale scores and radiofrequency thermocoagulation-related complications were evaluated preoperatively and at 1 day, 3 days, 7 days, 1 month, and 3 months after surgery. RESULTS: The number of punctures, the amount of time elapsed until the target area of the semilunar ganglion was punctured, and the cumulative dose of radiation exposure were all lower in the ultrasound+C-arm group than in the C-arm-only group (all P < 0.05). No significant differences were found in numerical rating scale scores and radiofrequency thermocoagulation-related complications between the two groups (P > 0.05). No puncture-related complications occurred in either of the groups. CONCLUSION: Ultrasound guidance combined with C-arm guidance could be safely used for puncturing the semilunar ganglion via the foramen ovale, with more efficiency and less radiation exposure than C-arm guidance alone.


Assuntos
Forame Oval , Neuralgia do Trigêmeo , Humanos , Neuralgia do Trigêmeo/diagnóstico por imagem , Neuralgia do Trigêmeo/cirurgia , Gânglio Trigeminal/diagnóstico por imagem , Gânglio Trigeminal/cirurgia , Eletrocoagulação/métodos , Fluoroscopia
19.
Am J Hum Biol ; 35(9): e23913, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37200487

RESUMO

BACKGROUND: This article aimed to study the adjustment and adaptation of resting systolic blood pressure (SBP), diastolic blood pressure (DPB), oxygen saturation (SpO2 ), hemoglobin concentration ([Hb]), and heart rate (HR) in low-altitude migrants during a 1-year stay at high altitude. MATERIALS AND METHODS: Our study enrolled 35 young migrants who were exposed to a hypoxia environment at 5380 m altitude on the Qinghai Tibetan Plateau between June 21, 2017, and June 16, 2018. We set 14-time points (the 1st-10th, 20th, 30th, 180th, and 360th day after arriving at 5380 m) for obtaining the measurements of resting SBP, DBP, HR, SpO2, and [Hb] and compared them with the control values recorded prior to migration. Variables with continuous data were summarized as means (SD). One-way repeated measures ANOVA without assuming sphericity was carried out to test whether the mean values (SBP, DBP, HR, SpO2 , and [Hb]) on different days were different significantly. Furthermore, Dunnett's multiple comparisons test was carried out to determine the time points whose values were significantly different from the control values. RESULTS: SBP and DBP were continually increasing within d1-3 and peaked on the 3rd day, then steadily declined from d3 to d30. SBP fell back to the control values on d10 (p > 0.05), and DBP fell back to the control values on d20 (p > 0.05). A significant decline occurred on d180 (p < 0.05). Both SBP and DBP were lower than the control values on d180 (p < 0.05), and this trend was maintained to d360. There were similar characteristics of HR and BP in the time course at HA. HR on d1-3 was increasing (p < 0.05) compared to the control values, after which it fell back to the control values on d180 (p > 0.05), and this trend was maintained to d360. SpO2 was the lowest on d1 and lower than the control value throughout the study at HA (p < 0.05). [Hb] increased after long-term exposure (180 and 360 days) to HA (p < 0.05). CONCLUSIONS: Our study continuously monitored lowlanders at 5380 m in Tibet, and is perhaps the only longitudinal study of migrants conducted at an altitude above 5000 m during a 1-year period. Our study provides new information on the adjustment and adaptation of [Hb], SpO2 , SBP, DBP, and HR in high-altitude plateau migrants during a 360-day stay at an altitude of 5380 m.


Assuntos
Altitude , Saturação de Oxigênio , Humanos , Pressão Sanguínea , Frequência Cardíaca/fisiologia , Estudos Longitudinais , Hemoglobinas , Oxigênio
20.
Sensors (Basel) ; 23(15)2023 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-37571671

RESUMO

In the shallow-water waveguide environment, the tonal signals radiated by moving targets carry modal interference and Doppler shift information. The modal interference can be used to obtain the time of the closest point of approach (tCPA) and the ratio of the range at the closest point of approach to the velocity of the source (rCPA/v). However, parameters rCPA and v cannot be solved separately. When tCPA is known, the rCPA and the v of the target can be obtained theoretically by using the Doppler information. However, when the Doppler frequency shift is small or at a low signal-to-noise ratio, there will be a strong parametric coupling between rCPA and v. In order to solve the above parameter coupling problem, a target motion parameter estimation method from tonal signals with a single hydrophone is proposed in this paper. The method uses the Doppler and modal interference information carried by the tonal signals to obtain two different parametric coupling curves. Then, the parametric coupling curves can be used to estimate the two motion parameters. Simulation experiments verified the rationality of this method. The proposed method was applied to the SWellEx-96 and speedboat experiments, and the estimation errors of the motion parameters were within 10%, which shows the method is effective in its practical applications.

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