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2.
Free Radic Biol Med ; 214: 173-183, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38342163

RESUMO

In comparison to other stroke types, subarachnoid hemorrhage (SAH) is characterized by an early age of onset and often results in poor prognosis. The inadequate blood flow at the site of the lesion leads to localized oxygen deprivation, increased level of hypoxia-inducible factor-1α (HIF-1α), and triggers inflammatory responses and oxidative stress, ultimately causing hypoxic brain damage. Despite the potential benefits of oxygen (O2) administration, there is currently a lack of efficient focal site O2 delivery following SAH. Conventional clinical O2 supply methods, such as transnasal oxygenation and hyperbaric oxygen therapy, do not show the ideal therapeutic effect in severe SAH patients. The perfluorocarbon oxygen carrier (PFOC) demonstrates efficacy in transporting O2 and responding to elevated levels of CO2 at the lesion site. Through cellular experiments, we determined that PFOC oxygenation serves as an effective therapeutic approach in inhibiting hypoxia. Furthermore, our animal experiments showed that PFOC oxygenation outperforms O2 breathing, leading to microglia phenotypic switching and the suppression of inflammatory response via the inhibition of HIF-1α. Therefore, as a new type of O2 therapy after SAH, PFOC oxygenation can effectively reduce hypoxic brain injury and improve neurological function.


Assuntos
Lesões Encefálicas , Fluorocarbonos , Hipóxia Encefálica , Hemorragia Subaracnóidea , Animais , Humanos , Oxigênio , Fluorocarbonos/uso terapêutico , Hipóxia Encefálica/terapia
3.
Am J Transl Res ; 16(1): 272-284, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38322575

RESUMO

Evidence suggests that damage to the ribbon synapses (RS) may be the main cause of auditory dysfunction in noise-induced hearing loss (NIHL). Oxidative stress is implicated in the pathophysiology of synaptic damage. However, the relationship between oxidative stress and RS damage in NIHL remains unclear. To investigate the hypothesis that noise-induced oxidative stress is a key factor in synaptic damage within the inner ear, we conducted a study using mice subjected to single or repeated noise exposure (NE). We assessed auditory function using auditory brainstem response (ABR) test and examined cochlear morphology by immunofluorescence staining. The results showed that mice that experienced a single NE exhibited a threshold shift and recovered within two weeks. The ABR wave I latencies were prolonged, and the amplitudes decreased, suggesting RS dysfunction. These changes were also demonstrated by the loss of RS as evidenced by immunofluorescence staining. However, we observed threshold shifts that did not return to baseline levels following secondary NE. Additionally, ABR wave I latencies and amplitudes exhibited notable changes. Immunofluorescence staining indicated not only severe damage to RS but also loss of outer hair cells. We also noted decreased T-AOC, ATP, and mitochondrial membrane potential levels, alongside increased hydrogen peroxide concentrations post-NE. Furthermore, the expression levels of 4-HNE and 8-OHdG in the cochlea were notably elevated. Collectively, our findings suggest that the production of reactive oxygen species leads to oxidative damage in the cochlea. This mitochondrial dysfunction consequently contributes to the loss of RS, precipitating an early onset of NIHL.

4.
Dev Comp Immunol ; 155: 105156, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38423493

RESUMO

Oncorhynchus masou formosanus (Formosa landlocked salmon) is a critically endangered salmonid fish endemic to Taiwan. To begin to understand how its drastic change in lifestyle from anadromous to exclusively river-dwelling is reflected in its immune genes, we characterized the genes encoding six cytokines (IL-2A, IL-2B, IL-4/13A, IL-4/13B1, IL-4/13B2, and IL-17A/F2a) important for T cell responses as no genomic data is available for this fish. Interestingly, all genes appeared homozygous indicative of a genetic bottleneck. The IL2 and IL17A/F2a genes and their products are highly similar to their characterized homologs in Oncorhynchus mykiss (rainbow trout) and other salmonid fish. Two notable differences were observed in IL4/13 family important for type 2 immune responses. First, O. m. formosanus carries not only one but two genes encoding IL-4/13B1 proteins and expansions of these genes are present in other salmonid fish. Second, the OmfoIL4/13A gene carries a 228 bp deletion that results in a premature stop codon and hence a non-functional IL-4/13A cytokine. This suggests a reduced ability for T cell responses against parasitic infections in this species.


Assuntos
Doenças dos Peixes , Oncorhynchus mykiss , Animais , Interleucina-4/genética , Interleucina-4/metabolismo , Citocinas/genética , Citocinas/metabolismo , Genoma
6.
Eur J Med Res ; 29(1): 40, 2024 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-38212838

RESUMO

BACKGROUND AND PURPOSE: Whether symptomatic unruptured intracranial aneurysms (UIAs) lead to change in circulating inflammation remains unclear. This study aims to evaluate the role of hematological inflammatory indicators in predicting symptomatic UIA. METHODS: Adult patients diagnosed with saccular intracranial aneurysm from March 2019 to September 2023 were recruited retrospectively. Clinical and laboratory data, including the white blood cells (WBC), neutral counts (NEUT), lymphocyte counts (LYM), and monocyte counts (MONO) of each patient, were collected. The neutrophil-to-lymphocyte ratio (NLR) and lymphocyte-to-monocyte ratio (LMR) were calculated as NLR = NEUT/LYM, LMR = LYM/MONO, SII = PLT*NEUT/LYM. The hematological inflammatory indicators were compared in symptomatic saccular and asymptomatic UIA patients. Multivariable logistic regression analyses were performed to explore the factors predicting symptomatic UIA. RESULTS: One hundred and fifty UIA patients with a mean age of 58.5 ± 12.4 were included, of which 68% were females. The NLR and LMR were significantly associated with symptomatic UIA, and the association remained in small UIAs (< 7 mm). The multiple logistic regression analysis showed that NLR was independently associated with symptomatic UIA. On ROC curve analysis, the optimal cutoff value of NLR to differentiate symptomatic from asymptomatic was 2.38. In addition, LMR was significantly associated with symptomatic UIA smaller than 7 mm. CONCLUSION: There was a significant correlation between NLR and symptomatic UIA. The NLR was independently associated with symptomatic UIA.


Assuntos
Aneurisma Intracraniano , Adulto , Feminino , Humanos , Pessoa de Meia-Idade , Idoso , Masculino , Aneurisma Intracraniano/complicações , Aneurisma Intracraniano/diagnóstico , Neutrófilos , Estudos Retrospectivos , Linfócitos , Contagem de Linfócitos
7.
World J Pediatr ; 20(1): 11-25, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38064012

RESUMO

BACKGROUND: Respiratory syncytial virus (RSV) is the leading global cause of respiratory infections and is responsible for about 3 million hospitalizations and more than 100,000 deaths annually in children younger than 5 years, representing a major global healthcare burden. There is a great unmet need for new agents and universal strategies to prevent RSV infections in early life. A multidisciplinary consensus development group comprising experts in epidemiology, infectious diseases, respiratory medicine, and methodology aims to develop the current consensus to address clinical issues of RSV infections in children. DATA SOURCES: The evidence searches and reviews were conducted using electronic databases, including PubMed, Embase, Web of Science, and the Cochrane Library, using variations in terms for "respiratory syncytial virus", "RSV", "lower respiratory tract infection", "bronchiolitis", "acute", "viral pneumonia", "neonatal", "infant" "children", and "pediatric". RESULTS: Evidence-based recommendations regarding diagnosis, treatment, and prevention were proposed with a high degree of consensus. Although supportive care remains the cornerstone for the management of RSV infections, new monoclonal antibodies, vaccines, drug therapies, and viral surveillance techniques are being rolled out. CONCLUSIONS: This consensus, based on international and national scientific evidence, reinforces the current recommendations and integrates the recent advances for optimal care and prevention of RSV infections. Further improvements in the management of RSV infections will require generating the highest quality of evidence through rigorously designed studies that possess little bias and sufficient capacity to identify clinically meaningful end points.


Assuntos
Bronquiolite , Infecções por Vírus Respiratório Sincicial , Infecções Respiratórias , Criança , Humanos , Infecções por Vírus Respiratório Sincicial/diagnóstico , Infecções por Vírus Respiratório Sincicial/prevenção & controle , Consenso , Vírus Sinciciais Respiratórios , Infecções Respiratórias/epidemiologia , Hospitalização
8.
N Engl J Med ; 389(22): 2113-4, 2023 11 30.
Artigo em Inglês | MEDLINE | ID: mdl-38048205
11.
Lasers Med Sci ; 38(1): 184, 2023 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-37578665

RESUMO

The aim of this study is to systematically summarize the available evidence regarding low-level laser therapy (LLLT) speed-up effect on dental alignment in comprehensive orthodontic treatment. An extensive electronic search was conducted in PubMed, ScienceDirect, Cochrane, Web of Science, and Scopus up to February 20, 2023. The Cochrane risk of bias tool and the Newcastle-Ottawa Quality Assessment Form were used by two authors independently to assess the risk of bias (RoB). Statistical analysis was performed by Review Manager 5.3. The eight eligible trials were reviewed and included in qualitative synthesis. Four studies reported the overall time of leveling and alignment (OLAT, days), enabling a synthesizing of the data. The meta-analysis results showed that LLLT significantly reduced the overall time of leveling and alignment compared to control group (MD=-30.36, 95% CI range -41.50 to -19.22, P<0.0001), with moderate heterogeneity (χ2=4.10, P=0.25, I2=27%). Based on the data available, statistically significant evidence with moderate risk of bias suggests that LLLT may have a positive effect on accelerating dental alignment. However, due to the differences in intervention strategy and evaluating method, the conclusions should be interpreted with caution.


Assuntos
Terapia com Luz de Baixa Intensidade , Técnicas de Movimentação Dentária , Fatores de Tempo , Técnicas de Movimentação Dentária/métodos
12.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 31(4): 1184-1191, 2023 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-37551496

RESUMO

OBJECTIVE: To investigate the correlation between plasmacytoid dendritic cell (pDC) dose in grafts and the occurrence of cytomegalovirus (CMV) infection after allogeneic hematopoietic stem cell transplantation (allo-HSCT). METHODS: The clinical data of 80 children who received allo-HSCT in Children's Hospital of Soochow University from August 20, 2020 to June 11, 2021 were retrospectively analyzed. Proportions of DC subsets and T-cell subsets in grafts were detected by flow cytometry in order to calculate infused cell dose of each cell. Weekly monitoring of CMV-DNA copies in peripheral blood for each child were performed after transplantation. The last follow-up date was December 31, 2021. RESULTS: All the children gained hematopoietic reconstitution. CMV infection was observed in 51 children (63.8%±5.4%) within the first 100 days after transplantation, including 2 cases developing CMV disease. Univariate analysis indicated that infused doses of DC and pDC were significantly associated with CMV infection within 100 days after allo-HSCT (P <0.05). Multivariate analysis indicated that a high dose infusion of pDC was an independent protective factor for CMV infection within 100 days after allo-HSCT (P <0.05). By the end of follow-up, 7 children died of transplantation-related complications, including 2 deaths from CMV disease, 2 deaths from extensive chronic graft-versus-host disease, and 3 deaths from capillary leak syndrome. The overall survival rate was 91.2%. CONCLUSION: The pDC in grafts may be associated with early infection of CMV after allo-HSCT, while a high infused pDC dose may serve as a protective factor for CMV infection after transplantation.


Assuntos
Infecções por Citomegalovirus , Doença Enxerto-Hospedeiro , Transplante de Células-Tronco Hematopoéticas , Criança , Humanos , Estudos Retrospectivos , Doença Enxerto-Hospedeiro/complicações , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Células Dendríticas
13.
Polymers (Basel) ; 15(14)2023 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-37514497

RESUMO

The ß-crystals of polypropylene have a metastable crystal form. The formation of ß-crystals can improve the toughness and heat resistance of a material. The introduction of a ß-nucleating agent, over many other methods, is undoubtedly the most reliable method through which to obtain ß-PP. Furthermore, in this study, certain newly developed ß-nucleating agents and their compounds in recent years are listed in detail, including the less-mentioned polymer ß-nucleating agents and their nucleation characteristics. In addition, the various influencing factors of ß-nucleation efficiency, including the polymer matrix and processing conditions, are analyzed in detail and the corresponding improvement measures are summarized. Finally, the composites and synergistic toughening effects are discussed, and three potential future research directions are speculated upon based on previous research.

14.
Psychopharmacology (Berl) ; 240(9): 1865-1876, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37490132

RESUMO

BACKGROUND: Diabetic encephalopathy is manifested by cognitive dysfunction. Salidroside, a nature compound isolated from Rhodiola rosea L, has the effects of anti-inflammatory and antioxidant, hypoglycemic and lipid-lowering, improving insulin resistance, inhibiting cell apoptosis, and protecting neurons. However, the mechanism by which salidroside alleviates neuronal degeneration and improves learning and memory impairment in diabetic mice remains unclear. OBJECTIVE: To investigate the effects and mechanisms of salidroside on hippocampal neurons in streptozotocin-induced diabetic mice. MATERIALS AND METHODS: C57BL/6 mice were randomly divided into 4 groups to receive either sham (control group (CON)), diabetes mellitus (diabetes group (DM)), diabetes mellitus + salidroside (salidroside group (DM + SAL)), and diabetes mellitus + salidroside + phosphatidylinositol 3-kinase (PI3K) inhibitor LY294002 (diabetes mellitus + salidroside + LY294002 group (DM + SAL + LY294002)). After 12 weeks of diabetes onset, the cognitive behaviors were tested using Morris water maze. The number of hippocampal neurons was detected by Nissl staining. The expressions of PI3K, p-PI3K, Akt, p-Akt, GSK-3ß, p-GSK-3ß, cleaved caspase-3, caspase-3, Bax, Bcl-2, MAP2, and SYN in the hippocampus were detected by Western blot. Moreover, the expression of MAP2 and SYN in the hippocampus was further confirmed by immunofluorescence staining. RESULTS: Salidroside increased the time of diabetic mice in the platform quadrant and reduced the escape latency of diabetic mice. Salidroside also increased the expression of p-PI3K, p-Akt, p-GSK-3ß, MAP2, SYN, Bcl-2, while suppressed the expression of cleaved caspase-3, caspase3, and Bax in the DM + SAL group compared with the DM group (P < 0.05). The Nissl staining showed that the number of hippocampus neurons in the DM + SAL group was increased with the intact, compact, and regular arrangement, compared with the DM groups (P < 0.05). Interestingly, the protective effects of salidroside on diabetic cognitive dysfunction, hippocampal morphological alterations, and protein expressions were abolished by inhibition of PI3K with LY294002. CONCLUSIONS: Salidroside exerts neuroprotective properties in diabetic cognitive dysfunction partly via activating the PI3K/Akt/GSK-3ß signaling pathway.


Assuntos
Encefalopatias , Hipocampo , Hipoglicemia , Fármacos Neuroprotetores , Animais , Camundongos , Apoptose/efeitos dos fármacos , Proteína X Associada a bcl-2/metabolismo , Caspase 3/metabolismo , Diabetes Mellitus Experimental/tratamento farmacológico , Diabetes Mellitus Experimental/metabolismo , Glicogênio Sintase Quinase 3 beta/metabolismo , Hipocampo/efeitos dos fármacos , Hipocampo/patologia , Camundongos Endogâmicos C57BL , Neurônios , Fármacos Neuroprotetores/farmacologia , Fármacos Neuroprotetores/uso terapêutico , Fosfatidilinositol 3-Quinase/metabolismo , Fosfatidilinositol 3-Quinase/farmacologia , Fosfatidilinositol 3-Quinases/metabolismo , Fosfatidilinositol 3-Quinases/farmacologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Transdução de Sinais , Encefalopatias/tratamento farmacológico , Hipoglicemia/tratamento farmacológico
15.
Sci Rep ; 13(1): 5871, 2023 04 11.
Artigo em Inglês | MEDLINE | ID: mdl-37041156

RESUMO

The aim of this study was to introduce a new technique, the bared external anal sphincter technique, and to evaluate its effectiveness and safety for primary or recurrent high horseshoe anal fistula (HHAF). We used data from a tertiary referral hospital's prospective database of a hospital-based cohort. All the patients underwent the bared external anal sphincter procedure. The main outcomes were short-term clinical outcomes including the 6-month cure rate, Visual Analog Scale pain score (VAS-PS) and Cleveland Clinic Florida incontinence score (CCF-IS). The secondary outcomes included the Quality of Life in Patients with Anal Fistula Questionnaire score (QoLAF-QS), Bristol stool chart and postoperative complications. A total of 48 HHAF patients (39 males) with a mean age of 34.2 years (SD 9.04; range, 21-54) were analyzed in this retrospective study. At the 6-month follow-up, the average VAS-PS and CCF-IS were 0.81 (SD 2.28; range, 0-10) and 1.29 (SD 2.87; range, 0-13), respectively. QoLAF-QS showed that the bared external anal sphincter procedure had no impact over their quality of life in 45 patients (93.75%), limited impact in 2 patients (4.16%), and moderate impact in one patient (2.08%). The Bristol stool scale showed that all patients had normal stool characteristics. The 6-month cure rate was 93.75%. Three patients (6.25%) experienced recurrent symptoms but recovered after surgical management. Urinary retention occurred in 1 case (2.78%). No other postoperative complications were reported. No patient had anal incontinence. The bared external anal sphincter procedure is a safe, effective and sphincter-sparing approach for patients with primary or recurrent HHAF in terms of short-term results.


Assuntos
Canal Anal , Fístula Retal , Masculino , Humanos , Adulto , Canal Anal/cirurgia , Estudos de Coortes , Estudos Retrospectivos , Qualidade de Vida , Tratamentos com Preservação do Órgão , Fístula Retal/cirurgia , Complicações Pós-Operatórias
16.
Metabolites ; 13(3)2023 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-36984875

RESUMO

From the rice fermentation product of a new record fungus, Neohelicosporium griseum, two new polyketides, neogrisphenol A (1) and neogrisphenol B (2), one new isochroman-1-one, (S)-6-hydroxy-7-methoxy-3,5-dimethylisochroman-1-one (3), and four known compounds (4-7) were isolated. Their structures were determined using 1D- and 2D-NMR, mass spectrometry, and chemical calculations. The C-3~C-2' polymerization mode between the two α-naphthalenone derivative moieties is uncommon in compounds 1 and 2. Meanwhile, compounds 1-2 and 5 exhibited antibacterial activity against Bacillus subtilis, Clostridium perfringens, Staphylococcus aureus, and Staphylococcus aureus, with MIC values ranging between 16 and 31 µg/mL. In addition, compound 5 showed antifungal activity against Sclerotinia sclerotiorum and Phytophthora nicotianae var. nicotianae, with respective IC50 values of 88.14 ± 2.21 µg/mL and 52.36 ± 1.38 µg/mL. Compound 1 showed significant cytotoxicity against A2780, PC-3, and MBA-MD-231 cell lines with respective IC50 values of 3.20, 10.68, and 16.30 µM, and the cytotoxicity against A2780 cells was even higher than that of cisplatin (CDDP). With an IC50 value of 10.13 µM, compound 2 also exhibited cytotoxicity against A2780. The in vitro results showed that compound 1 inhibited A2780 cell proliferation, induced apoptosis, and arrested the cell cycle at the S-phase in a concentration-dependent manner.

17.
World J Pediatr ; 19(9): 851-863, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36795317

RESUMO

BACKGROUND: Bronchiolitis is a common acute lower respiratory tract infection (ALRTI) and the most frequent cause of hospitalization of infants and young children with ALRTI. Respiratory syncytial virus is the main pathogen that leads to severe bronchiolitis. The disease burden is relatively high. To date, few descriptions of the clinical epidemiology and disease burden of children hospitalized for bronchiolitis are available. This study reports the general clinical epidemiological characteristics and disease burden of bronchiolitis in hospitalized children in China. METHODS: This study included the face sheet of discharge medical records collected from 27 tertiary children's hospitals from January 2016 to December 2020 that were aggregated into the FUTang Update medical REcords (FUTURE) database. The sociodemographic variables, length of stay (LOS) and disease burden of children with bronchiolitis were analyzed and compared using appropriate statistical tests. RESULTS: In total, 42,928 children aged 0-3 years were hospitalized due to bronchiolitis from January 2016 to December 2020, accounting for 1.5% of the total number of hospitalized children of the same age in the database during the period and 5.31% of the hospitalizations for ALRTI. The male to female ratio was 2.01:1. Meanwhile, more boys than girls were observed in different regions, age groups, years, and residences. The 1-2 year age group had the greatest number of hospitalizations for bronchiolitis, while the 29 days-6 months group had the largest proportion of the total inpatients and inpatients with ALRTI in the same age group. In terms of region, the hospitalization rate of bronchiolitis was the highest in East China. Overall, the number of hospitalizations from 2017 to 2020 showed a decreasing trend from that in 2016. Seasonally, the peak hospitalizations for bronchiolitis occurred in winter. Hospitalization rates in North China in autumn and winter were higher than those in South China, while hospitalization rates in South China were higher in spring and summer. Approximately, half of the patients with bronchiolitis had no complications. Among the complications, myocardial injury, abnormal liver function and diarrhea were more common. The median LOS was 6 days [interquartile range (IQR) = 5-8], and the median hospitalization cost was 758 United States dollars (IQR = 601.96-1029.53). CONCLUSIONS: Bronchiolitis is a common respiratory disease in infants and young children in China, and it accounts for a higher proportion of both total hospitalizations and hospitalizations due to ALRTI in children. Among them, children aged 29 days-2 years are the main hospitalized population, and the hospitalization rate of boys is significantly higher than that of girls. The peak season for bronchiolitis is winter. Bronchiolitis causes few complications and has a low mortality rate, but the burden of this disease is heavy.


Assuntos
Bronquiolite , Infecções por Vírus Respiratório Sincicial , Infecções Respiratórias , Criança , Lactente , Humanos , Masculino , Feminino , Pré-Escolar , Estudos Transversais , Infecções por Vírus Respiratório Sincicial/epidemiologia , Infecções por Vírus Respiratório Sincicial/terapia , Criança Hospitalizada , Bronquiolite/epidemiologia , Bronquiolite/terapia , Infecções Respiratórias/epidemiologia , Hospitalização , China/epidemiologia , Efeitos Psicossociais da Doença
18.
Eur J Med Res ; 28(1): 50, 2023 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-36707888

RESUMO

BACKGROUND: Miniscrews as auxiliary anchorage devices in orthodontic treatment have definite advantages and efficacy. The aim of the present study was to investigate the scientific evidence including randomized controlled trials (RCTs) or controlled clinical trials (CCTs) to support the application of low-level laser therapy to improve miniscrews stability in orthodontic treatment. METHODS: An extensive literature research was conducted with the Cochrane Library, PubMed, EMBASE, Web of Science and ScienceDirect without language limitations. All searches were inclusive until June 2020. The Cochrane Risk of Bias Tool was used to assess the risk of bias (RoB) in the included RCTs. RESULTS: Through the electronic searches, 428 titles and abstracts were identified. From these, 4 articles were retrieved for review, and 3 of these met the inclusion criteria. Two RCTs reported increased miniscrews stability with low-intensity laser therapy, but the other one reported no difference. Except one study assessed as "high risk of bias" the other two were rated as "low risk of bias". CONCLUSION: There is insufficient evidence to support or refute the effectiveness of LLLT for improvement of miniscrew stability. Further studies with a better study design, reliable evaluation method, comprehensive evaluation intervals and appropriate loading protocol are required to provide more reliable evidence for the clinical application of LLLT.


Assuntos
Terapia com Luz de Baixa Intensidade , Procedimentos de Ancoragem Ortodôntica , Humanos , Procedimentos de Ancoragem Ortodôntica/métodos
19.
J Am Chem Soc ; 145(4): 2195-2206, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36629383

RESUMO

Copper-based catalysts are widely explored in electrochemical CO2 reduction (CO2RR) because of their ability to convert CO2 into high-value-added multicarbon products. However, the poor stability and low selectivity limit the practical applications of these catalysts. Here, we proposed a simple and efficient asymmetric low-frequency pulsed strategy (ALPS) to significantly enhance the stability and the selectivity of the Cu-dimethylpyrazole complex Cu3(DMPz)3 catalyst in CO2RR. Under traditional potentiostatic conditions, Cu3(DMPz)3 exhibited poor CO2RR performance with the Faradaic efficiency (FE) of 34.5% for C2H4 and FE of 5.9% for CH4 as well as the low stability for less than 1 h. We optimized two distinguished ALPS methods toward CH4 and C2H4, correspondingly. The high selectivities of catalytic product CH4 (FECH4 = 80.3% and above 76.6% within 24 h) and C2H4 (FEC2H4 = 70.7% and above 66.8% within 24 h) can be obtained, respectively. The ultralong stability for 300 h (FECH4 > 60%) and 145 h (FEC2H4 > 50%) was also recorded with the ALPS method. Microscopy (HRTEM, SAED, and HAADF) measurements revealed that the ALPS method in situ generated and stabilized extremely dispersive and active Cu-based clusters (∼2.7 nm) from Cu3(DMPz)3. Meanwhile, ex situ spectroscopies (XPS, AES, and XANES) and in situ XANES indicated that this ALPS method modulated the Cu oxidation states, such as Cu(0 and I) with C2H4 selectivity and Cu(I and II) with CH4 selectivity. The mechanism under the ALPS methods was explored by in situ ATR-FTIR, in situ Raman, and DFT computation. The ALPS methods provide a new opportunity to boost the selectivity and stability of CO2RR.

20.
Nutr Metab Cardiovasc Dis ; 33(3): 500-506, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36646600

RESUMO

BACKGROUND AND AIMS: To investigate the relationship between elevated serum uric acid (SUA) levels and blood pressure (BP). METHODS AND RESULTS: Based on the Beijing Health Management Cohort, 5276 health examination people were enrolled. Cross-lagged model was used to explore the relationship between SUA levels and blood pressure. The results showed: (1) increased SUA and increased systolic blood pressure (SBP): ① The path coefficients from baseline SUA to follow-up SBP were statistically significant in both the general population (ß = 0.034, P < 0.05) and men (ß = 0.048, P < 0.05). The path coefficients from baseline SBP to follow-up SUA were not statistically significant in either the general population (ß = 0.010, P > 0.05) or men (ß = 0.011, P > 0.05). ② The path coefficients from baseline SUA to follow-up SBP and from baseline SBP to follow-up SUA were not statistically significant in women with BMI ≥ 25 kg/m2 and BMI < 25 kg/m2. (2) Increased SUA and diastolic blood pressure (DBP): ① There was no statistical significance between the path coefficients from baseline DBP to follow-up SUA and the path coefficients from baseline SUA to follow-up DBP. ② In men and women, BMI ≥ 25 kg/m2 and BMI < 25 kg/m2, the path coefficients from baseline DBP to follow-up SUA and from baseline SUA to follow-up DBP were not statistically significant. CONCLUSIONS: SUA can increase blood pressure in the general male population; no reverse time sequence relationship was found. The temporal relationships between SUA levels and SBP abnormalities were different in the sex and BMI subgroups. No bidirectional causal temporal relationship was found between SUA elevation and DBP abnormality.


Assuntos
Hipertensão , Humanos , Masculino , Feminino , Pressão Sanguínea/fisiologia , Hipertensão/diagnóstico , Hipertensão/epidemiologia , Hipertensão/etiologia , Ácido Úrico , Estudos de Coortes , Fatores de Risco
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