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1.
J Org Chem ; 89(3): 1956-1966, 2024 Feb 02.
Artículo en Inglés | MEDLINE | ID: mdl-38268404

RESUMEN

A general and practical methodology for the regio- and stereoselective synthesis of multifunctional tetrasubstituted allylic amines and azides based on iodoamination of ferrocene-containing allenylphosphonates with anilines and sodium azide is described. A tetrasubstituted olefin moiety, as well as an iodine atom, a phosphonate, and a ferrocene group, are installed to the allylic amine motif simultaneously in moderate to good yields.

2.
Acta Pharmacol Sin ; 2024 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-38702501

RESUMEN

Enteroendocrine cells (EECs) and vagal afferent neurons constitute functional sensory units of the gut, which have been implicated in bottom-up modulation of brain functions. Sodium oligomannate (GV-971) has been shown to improve cognitive functions in murine models of Alzheimer's disease (AD) and recently approved for the treatment of AD patients in China. In this study, we explored whether activation of the EECs-vagal afferent pathways was involved in the therapeutic effects of GV-971. We found that an enteroendocrine cell line RIN-14B displayed spontaneous calcium oscillations due to TRPA1-mediated calcium entry; perfusion of GV-971 (50, 100 mg/L) concentration-dependently enhanced the calcium oscillations in EECs. In ex vivo murine jejunum preparation, intraluminal infusion of GV-971 (500 mg/L) significantly increased the spontaneous and distension-induced discharge rate of the vagal afferent nerves. In wild-type mice, administration of GV-971 (100 mg· kg-1 ·d-1, i.g. for 7 days) significantly elevated serum serotonin and CCK levels and increased jejunal afferent nerve activity. In 7-month-old APP/PS1 mice, administration of GV-971 for 12 weeks significantly increased jejunal afferent nerve activity and improved the cognitive deficits in behavioral tests. Sweet taste receptor inhibitor Lactisole (0.5 mM) and the TRPA1 channel blocker HC-030031 (10 µM) negated the effects of GV-971 on calcium oscillations in RIN-14B cells as well as on jejunal afferent nerve activity. In APP/PS1 mice, co-administration of Lactisole (30 mg ·kg-1 ·d-1, i.g. for 12 weeks) attenuated the effects of GV-971 on serum serotonin and CCK levels, vagal afferent firing, and cognitive behaviors. We conclude that GV-971 activates sweet taste receptors and TRPA1, either directly or indirectly, to enhance calcium entry in enteroendocrine cells, resulting in increased CCK and 5-HT release and consequent increase of vagal afferent activity. GV-971 might activate the EECs-vagal afferent pathways to modulate cognitive functions.

3.
Nano Lett ; 23(1): 148-154, 2023 Jan 11.
Artículo en Inglés | MEDLINE | ID: mdl-36566458

RESUMEN

The power of surface chemistry to create atomically precise nanoarchitectures offers intriguing opportunities to advance the field of quantum technology. Strategies for building artificial electronic lattices by individually positioning atoms or molecules result in precisely tailored structures but lack structural robustness. Here, taking the advantage of strong bonding of Br atoms on noble metal surfaces, we report the production of stable quantum corrals by dehalogenation of hexabromobenzene molecules on a preheated Au(111) surface. The byproducts, Br adatoms, are confined within a new surface reconstruction pattern and aggregate into nanopores with an average size of 3.7 ± 0.1 nm, which create atomic orbital-like quantum resonance states inside each corral due to the interference of scattered electron waves. Remarkably, the atomic orbitals can be hybridized into molecular-like orbitals with distinct bonding and antibonding states. Our study opens up an avenue to fabricate quantum structures with high yield and superior robustness.

4.
Cardiovasc Diabetol ; 22(1): 268, 2023 09 30.
Artículo en Inglés | MEDLINE | ID: mdl-37777746

RESUMEN

BACKGROUND: Previous studies have reported that inflammatory responses can promote the onset of cardiovascular diseases; however, its association with cardiac conduction disorders remains unclear. The present community-based cohort study aimed to elucidate the effects of inflammatory responses on the risk of developing cardiac conduction disorders. METHODS: After the exclusion of participants failing to meet the inclusion criteria, 86,234 eligible participants (mean age: 50.57 ± 11.88 years) were included. The participants were divided into high-sensitivity C-reactive protein (hsCRP) ≤ 3 mg/L, and hsCRP > 3 mg/L groups based on hsCRP values. Multivariate Cox proportional hazard model was used to analyze the relationship between inflammatory responses and various cardiac conduction disorders. RESULTS: After adjusting for confounding factors, we observed that compared with the hsCRP ≤ 3 mg/L group, the hsCRP > 3 mg/L group exhibited increased risks of atrioventricular block (hazard ratio [HR]:1.64, 95%confidence interval [CI] 1.44-1.87) and left (HR:1.25, 95% CI 1.07-1.45) and right bundle branch block (HR:1.31, 95% CI 1.17-1.47). Moreover, the risk of various cardiac conduction disorders increased for every 1 standard deviation increase in log (hsCRP). The restricted cubic spline function confirmed a linear relationship between log (hsCRP) and the risk of developing cardiac conduction disorders (All nonlinearity P > 0.05). CONCLUSIONS: High hsCRP levels are an independent risk factor for cardiac conduction disorders, and hsCRP levels are dose-dependently associated with the risk of conduction disorders. Our study results may provide new strategies for preventing cardiac conduction disorders.


Asunto(s)
Proteína C-Reactiva , Enfermedades Cardiovasculares , Humanos , Adulto , Persona de Mediana Edad , Proteína C-Reactiva/análisis , Estudios de Cohortes , Factores de Riesgo
5.
BMC Gastroenterol ; 23(1): 270, 2023 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-37550605

RESUMEN

BACKGROUND: Colorectal cancer (CRC) is one of the most common malignancies in the world. This study proposes to reveal prognostic biomarkers for the prognosis and treatment of CRC patients. METHODS: Differential analysis of OSBPL3 was performed in pan-cancer, and the correlation between clinical stage and OSBPL3 was analyzed. Multiple omics analysis was used to compare the relationship between survival of patients and copy number variation, single nucleotide variant, and methylation status. Survival differences between high and low OSBPL3 expression groups were analyzed. Differentially expressed genes (DEGs) between high and low OSBPL3 expression groups were obtained, and functional enrichment analysis was implemented. Correlations between immune cells and OSBPL3 was analyzed. Drug sensitivity between the two OSBPL3 expression groups was compared. Moreover, the expression of OSBPL3 was verified by immunohistochemistry and real-time quantitative PCR. RESULTS: OSBPL3 was differentially expressed in 13 tumors and had some correlations with T and N stages. OSBPL3 expression was regulated by methylation and higher OSBPL3 expression was associated with poorer prognosis in CRC. 128 DEGs were obtained and they were mainly involved in signaling receptor activator activity, aspartate and glutamate metabolism. T cell gamma delta and T cell follicular helper were significantly different in the high and low OSBPL3 expression groups. Moreover, OSBPL3 showed negative correlations with multiple drugs. OSBPL3 was significantly upregulated in CRC samples compared to normal samples. CONCLUSIONS: A comprehensive analysis demonstrated that OSBPL3 had potential prognostic value, and guiding significance for CRC chemotherapeutic.


Asunto(s)
Neoplasias Colorrectales , Multiómica , Humanos , Pronóstico , Variaciones en el Número de Copia de ADN , Transducción de Señal/genética , Neoplasias Colorrectales/patología , Regulación Neoplásica de la Expresión Génica , Biomarcadores de Tumor/genética , Biomarcadores de Tumor/metabolismo , Proteínas de Unión a Ácidos Grasos
6.
J Neurosci ; 41(37): 7727-7741, 2021 09 15.
Artículo en Inglés | MEDLINE | ID: mdl-34349001

RESUMEN

Chronic itch is a troublesome condition and often difficult to cure. Emerging evidence suggests that the periaqueductal gray (PAG)-rostral ventromedial medulla (RVM) pathway may play an important role in the regulation of itch, but the cellular organization and molecular mechanisms remain incompletely understood. Here, we report that a group of RVM neurons distinctively express the G-protein-coupled estrogen receptor (GPER), which mediates descending inhibition of itch. We found that GPER+ neurons in the RVM were activated in chronic itch conditions in rats and mice. Selective ablation or chemogenetic suppression of RVM GPER+ neurons resulted in mechanical alloknesis and increased scratching in response to pruritogens, whereas chemogenetic activation of GPER+ neurons abrogated itch responses, indicating that GPER+ neurons are antipruritic. Moreover, GPER-deficient mice and rats of either sex exhibited hypersensitivity to mechanical and chemical itch, a phenotype reversible by the µ type opioid receptor (MOR) antagonism. Additionally, significant MOR phosphorylation in the RVM was detected in chronic itch models in wild-type but not in GPER-/- rats. Therefore, GPER not only identifies a population of medullary antipruritic neurons but may also determine the descending antipruritic tone through regulating µ opioid signaling.SIGNIFICANCE STATEMENT Therapeutic options for itch are limited because of an as yet incomplete understanding of the mechanisms of itch processing. Our data have provided novel insights into the cellular organization and molecular mechanisms of descending regulation of itch in normal and pathologic conditions. GPER+ neurons (largely GABAergic) in the RVM are antipruritic neurons under tonic opioidergic inhibition, activation of GPER promotes phosphorylation of MOR and disinhibition of the antipruritic GPER+ neurons from inhibitory opioidergic inputs, and failure to mobilize GPER+ neurons may result in the exacerbation of itch. Our data also illuminate on some of the outstanding questions in the field, such as the mechanisms underlying sex bias in itch, pain, and opioid analgesia and the paradoxical effects of morphine on pain and itch.


Asunto(s)
Bulbo Raquídeo/metabolismo , Neuronas/metabolismo , Receptores de Estrógenos/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Animales , Femenino , Masculino , Ratones , Fosforilación , Prurito/genética , Prurito/metabolismo , Receptores de Estrógenos/genética , Receptores Acoplados a Proteínas G/genética , Receptores Opioides mu/metabolismo , Transducción de Señal/fisiología
7.
J Gene Med ; 24(2): e3397, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-34751492

RESUMEN

BACKGROUND: Aberrant expression of m6A-related proteins contributes to the occurrence and progression of non-small cell lung cancer (NSCLC). Current studies mainly focus on single m6A regulatory genes and their underlying mechanisms, and the expression of multiple m6A regulatory proteins in NSCLC remains unclear. Therefore, it is necessary to systematically examine these proteins, particularly in clinical specimens. METHODS: Bioinformatic analysis was used to determine the expression of m6A regulatory genes and their correlation with common gene mutations, such as TP53, EGFR and KRAS, using The Cancer Genome Atlas (TCGA) and the AE-meta databases. Immunohistochemistry was employed to analyze the protein expression of m6A regulatory proteins in 61 benign lung tissues and 316 NSCLC tissues. Statistical analysis was performed to calculate the correlation between the expression of m6A regulatory proteins and clinicopathological features, survival, and common gene mutations in lung carcinoma patients. RESULTS: Analysis of the mRNA levels of 13 core m6A regulators, using information from TCGA and the AE-meta databases, revealed that YTHDF1 levels were upregulated in NSCLC compared to those in adjacent normal tissues. Immunohistochemical staining showed that the expression of METTL3, ALKBH5, YTHDC2 and YTHDF1 was significantly upregulated in NSCLC tissues. Further analyses demonstrated a positive correlation between differentially expressed m6A regulatory proteins, including METTL3, ALKBH5, YTHDC2 and YTHDF1, and the poor clinicopathological features and survival of NSCLC patients. According to the statistics of NSCLC patients enrolled in the present study, the protein levels of METTL3 in patients with EGFR exon-19 mutation were higher than those in patients with wild-type EGFR. CONCLUSIONS: Our results indicate that m6A regulators, including METTL3, ALKBH5, YTHDC2 and YTHDF1, could serve as predictive markers of NSCLC, which will facilitate the early detection and diagnosis of NSCLC.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Adenosina/genética , Adenosina/metabolismo , Carcinoma de Pulmón de Células no Pequeñas/genética , Receptores ErbB/genética , Genes Reguladores , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patología , Metiltransferasas/genética
8.
BMC Cancer ; 22(1): 922, 2022 Aug 26.
Artículo en Inglés | MEDLINE | ID: mdl-36028821

RESUMEN

BACKGROUND: Lymph node metastasis (LNM) is a critical event during the colorectal cancer (CRC) development and is indicative of poor prognosis. Identification of molecular markers of LNM may facilitate better therapeutic decision-making. METHODS: Six pairs of CRC tissues and corresponding adjacent tissues [3 pairs diagnosed as pT1N0M0 (M_Low group) and 3 pairs diagnosed as pT4N2M0 (M_High group)] collected from CRC patients who underwent surgical resection were used. MicroRNA sequencing was performed to screen differential microRNAs involved in CRC LNM. The selected microRNAs were validated in CRC tissues and cell lines using qRT-PCR. The functions of candidate hsa-miR-1248 were evaluated by CCK-8, colony formation, and Transwell assay. The binding of hsa-miR-1248 with its target PSMD10 was confirmed by luciferase activity assay, and the expression of PSMD10 in tissues was detected by droplet digital polymerase chain reaction. RESULTS: Ninety-five miRNAs were downregulated in carcinoma tissues (M_Low and M_high groups) compared with the normal group. Their expression in M_High group was significantly lower compared with M_Low group. The top 3 were hsa-miR-635, hsa-miR-1248, and hsa-miR-668-3p. After validation in tissues/cell lines, only hsa- hsa-miR-1248 was decreased in high metastatic tissues or SW620 cells compared to low metastatic tissues or SW480 cells. Hsa-miR-1248 was found to inhibit CRC cell viability, proliferation, invasion, and migration. The tumor suppressor effect of has-miR-1248 in CRC cells was attenuated or enhanced by up-regulating or down-regulating PSMD10, respectively. CONCLUSION: Hsa-miR-1248 may act as a tumor suppressor gene in CRC by targeting and inhibiting PSMD10, which provides a clue for CRC treatment.


Asunto(s)
Neoplasias Colorrectales , MicroARNs , Complejo de la Endopetidasa Proteasomal , Proteínas Proto-Oncogénicas , Línea Celular Tumoral , Movimiento Celular , Proliferación Celular , Neoplasias Colorrectales/genética , Regulación Neoplásica de la Expresión Génica , Genes Supresores de Tumor , Humanos , Metástasis Linfática , MicroARNs/genética , Complejo de la Endopetidasa Proteasomal/genética , Proteínas Proto-Oncogénicas/genética
9.
Pharmacol Res ; 172: 105796, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34343656

RESUMEN

Restoring immune balance by targeting macrophage polarization is a potentially valuable therapeutic strategy for ulcerative colitis (UC). Dioscin is a steroidal saponin with potent anti-inflammatory, immunoregulatory, and hypolipidemic effects. This study examined the protective effect of Dioscin on UC in mice and explored the underlying mechanisms. Mice were induced colitis by dextran sulfate sodium (DSS) and concurrently treated with Dioscin oral administration. RAW264.7 cells were skewed to M1 macrophage polarization by lipopolysaccharide (LPS) and interferon-γ (INF-γ) in vitro, and received Dioscin treatment. The results showed that Dioscin ameliorated colitis in mice, reduced macrophage M1 polarization, but markedly promoted M2 polarization in mice colon. Dioscin inhibited mammalian target rapamycin complex 1 (mTORC1)/hypoxia-inducible factor-1α (HIF-1α) signaling and restrained glycolysis in RAW264.7; however, it activated mammalian target rapamycin complex 2 (mTORC2)/peroxisome proliferator-activated receptor-γ (PPAR-γ) signal and facilitated fatty acid oxidation (FAO). The modulation of mTORs signaling may inhibit M1, but promote M2 polarization. Furthermore, the effect of Dioscin on M2 polarization was neutralized by the FAO inhibitor Etomoxir and the mTORC2 inhibitor JR-AB2-011. In parallel, the inhibitory effect of Dioscin on M1 polarization was mitigated by the mTORC1 agonist L-leucine. Both JR-AB2-011 and L-leucine blocked the therapeutic effect of Dioscin in mice with UC. Therefore, Dioscin ameliorated UC in mice, possibly by restraining M1, while skewing M2 polarization of macrophages. Regulation of mTORC1/HIF-1α and mTORC2/PPAR-γ signals is a possible mechanism by which Dioscin inhibited aerobic glycolysis and promoted FAO of macrophages. In summary, Dioscin protected mice against DSS-induced UC by regulating mTOR signaling, thereby adjusting macrophage metabolism and polarization.


Asunto(s)
Antiinflamatorios/uso terapéutico , Colitis Ulcerosa/tratamiento farmacológico , Diosgenina/análogos & derivados , Macrófagos/efectos de los fármacos , Animales , Antiinflamatorios/farmacología , Colitis Ulcerosa/inducido químicamente , Colitis Ulcerosa/inmunología , Colitis Ulcerosa/patología , Colon/efectos de los fármacos , Colon/inmunología , Colon/patología , Citocinas/genética , Sulfato de Dextran , Diosgenina/farmacología , Diosgenina/uso terapéutico , Modelos Animales de Enfermedad , Subunidad alfa del Factor 1 Inducible por Hipoxia/antagonistas & inhibidores , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , Macrófagos/inmunología , Masculino , Diana Mecanicista del Complejo 1 de la Rapamicina/antagonistas & inhibidores , Diana Mecanicista del Complejo 1 de la Rapamicina/metabolismo , Ratones , Ratones Endogámicos BALB C , PPAR gamma/metabolismo , Células RAW 264.7
10.
Blood Purif ; 50(6): 876-882, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33508826

RESUMEN

BACKGROUND: Cholestasis may lead to hepatic cirrhosis and a longer hospital stay. A part of the patients with cholestasis requires liver transplantation. However, most of the treatment efficiency of cholestatic hepatitis (CH) is not satisfactory. For the patients with severe CH after artificial liver support, there was a lack of systemic evaluation on the treatment efficiency of double plasma molecular absorption system (DPMAS) for acute severe CH. OBJECTIVE: We aim to investigate the treatment efficiency of DPMAS on acute severe CH. METHODS: This retrospective study involved 309 cases diagnosed with acute severe CH admitted to the First Affiliated Hospital, Zhejiang University. We compared the prognosis of patients received standard medical therapy (SMT) and SMT + DPMAS. Besides, the effects of DPMAS on total bilirubin (TBIL) and prothrombin time (PT) were investigated. RESULTS: DPMAS could significantly reduce the requirements for liver transplantation in the CH patients. After DPMAS therapy, significant decline was noticed in the TBIL, direct bilirubin (DBIL), total bile acid, and cholesterol. The baseline ratio of neutrophil showed significant elevation in the patients received 4 or more DPMAS compared with those received less DPMAS. CONCLUSIONS: DPMAS could significantly eliminate the necessity of liver transplantation. The artificial liver support system should be conducted to bring down the bilirubin level and the ratio of cases with severe conditions. In general, DPMAS should be preferred as an artificial liver support therapy for the patients with acute severe CH.


Asunto(s)
Colestasis/terapia , Hepatitis/terapia , Intercambio Plasmático/instrumentación , Adsorción , Adulto , Anciano , Colestasis/complicaciones , Femenino , Hepatitis/complicaciones , Humanos , Hígado Artificial , Masculino , Persona de Mediana Edad , Intercambio Plasmático/métodos , Estudios Retrospectivos , Resultado del Tratamiento
11.
BMC Public Health ; 21(1): 1374, 2021 07 12.
Artículo en Inglés | MEDLINE | ID: mdl-34247618

RESUMEN

BACKGROUND: Public health measures, such as social isolation, are vital to control the spread of the coronavirus disease 2019 (COVID-19), but such measures may increase the risk of depression. Thus, this study examines the influencing and moderating factors of depressive symptoms among individuals subjected to mandatory social isolation. METHODS: An online cross-sectional survey was conducted to collect data from people under mandatory home or centralized social isolation in Shenzhen, China, from February 28 to March 6, 2020. The perceived risk of infection with COVID-19, perceived tone of media coverage, perceived quality of people-oriented public health services, and their depressive symptoms were assessed. Three rounds of stepwise multiple regression were performed to examine the moderating effects after controlling various variables, such as demographics, duration and venue of mandatory social isolation, infection and isolation status of family, time spent on COVID-related news, and online social support. RESULTS: Among the 340 participants, 57.6% were men, the average age was 35.5 years old (SD = 8.37), and 55.6% held a bachelor's degree or above. Individuals subjected to mandatory social isolation generally reported low levels of depressive symptoms. Perceived susceptibility to infection was relatively low, whereas perceived tone of media coverage was mainly positive. In terms of perceived quality of public health services, 12 (3.5%), 103 (30.3%), and 225 (66.2%) participants reported low, medium, and high quality of people-oriented services, respectively. Perceived susceptibility was positively associated with depression, whereas perceived tone of media coverage was negatively associated. The quality of people-centered public health services moderated the association between perceived risk and depressive symptoms and between perceived tone of media coverage and depressive symptoms. CONCLUSIONS: This study revealed the depressive symptoms among individuals subjected to mandatory social isolation during the COVID-19 pandemic and highlighted that frontline public health workers play a critical role in protecting public mental health.


Asunto(s)
COVID-19 , Pandemias , Adulto , Ansiedad , China/epidemiología , Estudios Transversales , Depresión/epidemiología , Servicios de Salud , Humanos , Masculino , SARS-CoV-2 , Aislamiento Social
12.
Opt Express ; 28(13): 18843-18858, 2020 Jun 22.
Artículo en Inglés | MEDLINE | ID: mdl-32672175

RESUMEN

Semiconductor-based surface enhanced Raman scattering (SERS) substrate design has attracted much interest due to the excellent photoelectronic and biochemical properties. The structural change caused by twin in semiconductor will have an influence on improving the Raman signals enhancement based on the chemical mechanism (CM). Here, we demonstrated the twin in semiconductor ZnSe nanowires as an ultrasensitive CM-based SERS platform. The SERS signals of the rhodamine 6G (R6G) and crystal violet (CV) molecules adsorbed on twin-ZnSe nanowires could be easily detected even with an ultralow concentration of 10-11 M and 10-8 M, respectively, and the corresponding enhancement factor (EF) were up to 6.12 × 107 and 3.02 × 105, respectively. In addition, the charge transfer (CT) between the twin-ZnSe nanowires and R6G molecule has been demonstrated theoretically with first-principles calculations based on density-functional theory (DFT). These results demonstrated the proposed ZnSe nanowires with twin as SERS substrate has a broader application in the field of biochemical sensing.

13.
Neural Plast ; 2020: 8866187, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32908490

RESUMEN

Ample evidence suggests that estrogens have strong influences on the occurrence of stress-related mood disorders, but the underlying mechanisms remain poorly understood. Through multiple approaches, we demonstrate that the G protein-coupled estrogen receptor (GPER) is widely distributed along the HPA axis and in brain structures critically involved in mood control. Genetic ablation of GPER in the rat resulted in significantly lower basal serum corticosterone level but enhanced ACTH release in response to acute restraint stress, especially in the female. GPER-/- rats of either sex displayed increased anxiety-like behaviors and deficits in learning and memory. Additionally, GPER deficiency led to aggravation of anxiety-like behaviors following single-prolonged stress (SPS). SPS caused significant decreases in serum corticosterone in WT but not in GPER-deficient rats. The results highlight an important role of GPER at multiple sites in regulation of the HPA axis and mood.


Asunto(s)
Ansiedad/sangre , Ansiedad/fisiopatología , Corticosterona/sangre , Sistema Hipotálamo-Hipofisario/fisiopatología , Sistema Hipófiso-Suprarrenal/fisiopatología , Receptores Acoplados a Proteínas G/fisiología , Hormona Adrenocorticotrópica/sangre , Animales , Conducta Animal , Femenino , Técnicas de Inactivación de Genes , Hipocampo/fisiología , Masculino , Ratas Transgénicas
15.
Inorg Chem ; 56(14): 8355-8362, 2017 Jul 17.
Artículo en Inglés | MEDLINE | ID: mdl-28649830

RESUMEN

Decreasing Li/Ni disorder has been a challenging problem for layered oxide materials, where disorder seriously restricts their electrochemical performances for lithium-ion batteries (LIBs). Element doping is a great strategy that has been widely used to stabilize the structure of the cathode material of an LIB and improve its electrochemical performance. On the basis of the results of previous studies, we hypothesized that the element of Ca, which has a lower valence state and larger radius compared to Ni2+, would be an ideal doping element to decrease the Li/Ni disorder of LiMO2 materials and enhance their electrochemical performances. A Ni-rich LiNi0.8Mn0.1Co0.1O2 cathode material was selected as the bare material, which usually shows severe Li/Ni disorder and serious capacity attenuation at a high cutoff voltage. So, a series of Ca-doped LiNi0.8(1-x)Co0.1Mn0.1Ca0.8xO2 (x = 0-8%) samples were synthesized by a traditional solid-state method. As hypothesized, neutron diffraction showed that Ca-doped LiNi0.8Co0.1Mn0.1O2 possessed a lower degree of Li/Ni disorder, and potentiostatic intermittent titration results showed a faster diffusion coefficient of Li+ compared with that of LiNi0.8Mn0.1Co0.1O2. The Ca-doped LiNi0.8Mn0.1Co0.1O2 samples exhibited higher discharge capacities and better cycle stabilities and rate capabilities, especially under a high cutoff voltage with 4.5 V. In addition, the problems of polarization and voltage reduction of LiNi0.8Mn0.1Co0.1O2 were also alleviated by doping with Ca. More importantly, we infer that it is crucial to choose an appropriate doping element and our findings will help in the research of other layered oxide materials.

16.
Inorg Chem ; 56(6): 3475-3482, 2017 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-28240880

RESUMEN

Copper-doped (Tb0.861Mn0.121)MnO3-δ has been synthesized by the conventional solid state reaction method. X-ray, neutron, and electron diffraction data indicate that they crystallize in Pnma space group at room temperature. Two magnetic orderings are found for this series by neutron diffraction. One is the ICAM (incommensurate canted antiferromagnetic) ordering of Mn with a wave vector qMn = (∼0.283, 0, 0) with a ≈ 5.73 Å, b ≈ 5.31 Å, and c ≈ 7.41 Å, and the other is the CAM (canted antiferromagnetic) ordering of both Tb and Mn in the magnetic space group Pn'a21' with a ≈ 5.73 Å, b ≈ 5.31 Å, and c ≈ 7.41 Å. A dielectric peak around 40 K is found for the samples doped with Cu, which is higher than that for orthorhombic TbMnO3.

17.
Sheng Li Xue Bao ; 69(5): 532-540, 2017 Oct 25.
Artículo en Inglés | MEDLINE | ID: mdl-29063102

RESUMEN

Numerous studies have demonstrated that estrogens may exert multifaceted effects on the cardiovascular system via activating the classical nuclear receptors ERα or ERß and the novel G protein coupled estrogen receptor (Gper). However, some studies have reported inconsistent cardiovascular phenotypes in Gper-deficient mice. The current study was aimed to reveal the effects of genetic deletion of Gper on the arterial blood pressure (ABP) and heart rate in rats. Gper-deficient Sprague-Dawley rats were generated by utilizing the CRISPR-Cas9 gene-editing technique. ABP of 10-week old male (n = 6) and 12-week old female (n = 6) Gper-deficient rats and age-matched wild type (WT) rats (6 females and 6 males) were measured under awake and restrained conditions through the non-invasive tail-cuff method daily for 8 (females) or 9 days (males). In the male WT rats, ABP and heart rate were slightly higher in day 1 to 4 than those in day 5 to 9, indicative of stress-related sympathoexcitation in the first few days and gradual adaptation to the restrained stress in later days. Gper-deficient rats had significantly higher ABP initially (male: day 1 to day 5; female: day 1 to day 3) and similar ABP in later days of measurement compared with the WT rats. The heart rate of male Gper-deficient rats was consistently higher than that of the male WT rats from day 1 to day 8. Both male and female Gper-deficient rats appeared to show slower body weight gain than the WT counterparts during the study period. Under anesthesia, ABP of Gper-deficient rats was not significantly different from their WT counterparts. These results indicate that Gper-deficient rats may be more sensitive to stress-induced sympathoexcitation and highlight the importance of Gper in the regulation of the cardiovascular function in stressful conditions.


Asunto(s)
Hipertensión/etiología , Receptores de Estrógenos/fisiología , Receptores Acoplados a Proteínas G/fisiología , Estrés Psicológico/complicaciones , Animales , Femenino , Masculino , Ratas , Ratas Sprague-Dawley
18.
Inorg Chem ; 53(17): 9206-12, 2014 Sep 02.
Artículo en Inglés | MEDLINE | ID: mdl-25140828

RESUMEN

The crystal structures, phase transition, and thermal expansion behaviors of solid solutions of Sc(2-x)Fe(x)Mo3O12 (0 ≤ x ≤ 2) have been examined using X-ray diffraction (XRD), neutron powder diffraction (NPD), and differential scanning calorimetry (DSC). At room temperature, samples crystallize in a single orthorhombic structure for the compositions of x < 0.6 and monoclinic for x ≥ 0.6, respectively. DSC results indicate that the phase transition temperature from monoclinic to orthorhombic structure is enhanced by increasing the Fe(3+) content. High-temperature XRD and NPD results show that Sc(1.3)Fe(0.7)Mo3O12 exhibits near zero thermal expansion, and the volumetric coefficients of thermal expansion derived from XRD and NPD are 0.28 × 10(-6) °C(-1) (250-800 °C) and 0.65 × 10(-6) °C(-1) (227-427 °C), respectively. NPD results of Sc2Mo3O12 (x = 0) and Sc(1.3)Fe(0.7)Mo3O12 (x = 0.7) indicate that Fe substitution for Sc induces reduction of the mean Sc(Fe)-Mo nonbond distance and the different thermal variations of Sc(Fe)-O5-Mo2 and Sc(Fe)-O3-Mo2 bond angles. The correlation between the displacements of oxygen atoms and the variation of unit cell parameters was investigated in detail for Sc2Mo3O12.

19.
Inorg Chem ; 53(4): 2317-24, 2014 Feb 17.
Artículo en Inglés | MEDLINE | ID: mdl-24491172

RESUMEN

The crystal and magnetic structures of antiperovskite compounds Mn3SnC, Mn3Sn0.95C0.9, and Mn3Sn0.93Si0.07C0.94 were studied as a function of temperature and magnetic field by neutron powder diffraction. For Mn3SnC, the magnetic field induces a dramatic variation of antiferromagnetic moment and lattice parameter. Because of this spin-lattice coupling, the "square" antiferromagnetic (AFM) structure plays a key role in inducing a negative thermal expansion in the material. Moreover, the thermal expansion parameter is closely related to the rate of change of the AFM moment, which can be controlled by introducing vacancies or by doping. The variations of the AFM moment and lattice parameter in Mn3SnC with magnetic field make it possible to use the tunable properties for technical applications.

20.
Technol Health Care ; 32(4): 2243-2250, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38251074

RESUMEN

BACKGROUND: During the COVID-19 pandemic, the mobile field hospital, a rapidly deployable healthcare facility for emergency care, was effective in ensuring rapid diagnosis and treatment of patients with mild or asymptomatic SARS-CoV2 infections, effectively preventing the spread of COVID-19. OBJECTIVE: We conducted a survey to gain a thorough understanding of the epidemiological traits among the elderly who contracted the Omicron variant of the SARS-CoV-2 virus at a mobile field hospital set up at the National Exhibition and Convention Center (Shanghai). METHODS: A cross-sectional study approach was employed to examine various factors such as demographic characteristics, clinical features, vaccination status, and nucleic acid testing. We utilized the DezhenTech Integrated Electronic Medical Record Platform (Municipal Isolation Hospital) to collect data and focused on elderly individuals infected with COVID-19 in the fifth isolation zone of the mobile field hospital set up at the National Exhibition and Convention Center (Shanghai). The patients were categorized into different age groups for analysis. RESULTS: Among the 3,183 elderly patients, 54.7% were males and 45.3% were females, with an average age of 65.32 ± 4.41 years. Among them, 47.8% (1523/3183) were 60-64 years old, 34.0% (1082/3183) were 65-69 years old, 14.0% (444/3183) were 70-74 years old, 3.2% (103/3183) were 75-79 years old, and 1.0% (31/3183) were ⩾ 80 years old. The majority (95.7%) of the elderly patients with chronic conditions had hypertension, diabetes, and coronary heart disease. The first viral nucleic acid screening showed a higher positive rate in the community and hospital fever clinics. The cumulative positive rate of the nucleic acid test in the mobile field hospital was 38.7%. The average CT value of the COVID-19 ORF1ab gene was 34.56 ± 5.98, while the average CT value of the N gene was 33.10 ± 6.50. The patients took an average of 3.40 ± 0.45 days to test negative, with a positive rate of 15.4% and an average hospital stay of 7.45 ± 0.53 days. The overall rate of COVID-19 vaccine coverage was 68.0%, with an enhanced coverage rate of 40% and a non-coverage rate of 29.3%. CONCLUSIONS: The overall prognosis for elderly patients who experienced a mild or asymptomatic SARS-CoV-2 Omicron infection at the mobile field hospital was favorable, although the vaccination rate in general was not high. By effectively managing underlying health conditions, the duration of their hospital stay in the mobile field hospital was reduced.


Asunto(s)
COVID-19 , Unidades Móviles de Salud , SARS-CoV-2 , Humanos , COVID-19/epidemiología , Femenino , Anciano , Masculino , Estudios Transversales , Persona de Mediana Edad , China/epidemiología , Anciano de 80 o más Años , Pandemias
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