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1.
Diabetes Obes Metab ; 26(3): 871-877, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38012837

RESUMEN

AIM: Whether systolic/diastolic blood pressure (SBP/DBP) values of 130-139/80-89 mmHg should be defined as hypertension has been debated for decades. We aimed to characterize the effect of high-normal BP on cardiovascular disease (CVD) events and deaths. METHODS: In total, 1726 individuals from the original Da Qing IGT and Diabetes Study were enrolled, and divided into the normal BP group (SBP <130 mmHg and DBP <80 mmHg), high-normal BP group (SBP 130-139 mmHg and/or DBP 80-89 mmHg) and hypertension group (SBP ≥140 mmHg and/or DBP ≥90 mmHg). CVD events and their components were assessed from 1986 to 2016. RESULTS: During the 30-year follow-up, the high-normal BP group was not at higher risk for CVD events [hazard ratio (HR) 1.05, 95% confidence interval (CI) 0.84-1.30, p = .68], coronary heart disease (HR 1.12, 95% CI 0.77-1.63, p = .57), stroke (HR 1.05, 95% CI 0.82-1.34, p = .71), or CVD deaths (HR 1.15, 95% CI 0.82-1.60, p = .41) compared with the normal BP group, after adjusting for covariates. However, the hypertension group exhibited significantly increased cardiovascular risk (CVD events, HR 1.91, 95% CI 1.48-2.46, p < .0001; coronary heart disease, HR 1.73, 95% CI 1.12-2.67, p = .01; stroke, HR 1.90, 95% CI 1.43-2.52, p < .0001; CVD deaths, HR 2.07, 95% CI 1.43-3.01, p = .0001) than the normal BP group. Subgroup analyses showed that, regardless of the presence of diabetes, high-normal BP did not increase CVD events compared with normal BP. CONCLUSIONS: This post-hoc study provided no evidence that the high-normal BP increased cardiovascular risk in the Da Qing study population, suggesting that it was reasonable to continue to define hypertension at 140/90 mmHg in China.


Asunto(s)
Presión Sanguínea , Enfermedades Cardiovasculares , Pueblos del Este de Asia , Hipertensión , Humanos , Presión Sanguínea/fisiología , Enfermedades Cardiovasculares/epidemiología , Enfermedad Coronaria/epidemiología , Diabetes Mellitus/epidemiología , Estudios de Seguimiento , Hipertensión/complicaciones , Hipertensión/diagnóstico , Hipertensión/epidemiología , Factores de Riesgo , Accidente Cerebrovascular/epidemiología
2.
Artículo en Inglés | MEDLINE | ID: mdl-38866618

RESUMEN

BACKGROUND AND AIMS: We aimed to explore the association between remnant cholesterol (RC) level and risks of all-cause and cardiovascular deaths among American diabetic adults. METHODS AND RESULTS: The data of 4,095 diabetic participants from the National Health and Nutrition Examination Survey (1999-2018) were included for analysis. Deaths were ascertained till December 31, 2019. RC level associated with death was assessed on a continuous scale with restricted cubic splines and by pre-defined quartile groups with Cox regression analysis. After a median follow-up of 6.9 years, 1,060 all-cause and 289 cardiovascular deaths occurred. Association between RC and death was U-shaped, and RC level correlated with the lowest risks of both all-cause and cardiovascular deaths was 0.85 mmol/L. After adjusting for confounders, compared with Quartile 3 (0.66-0.93 mmol/L), hazard ratios for all-cause deaths were 1.43 (95%CI 1.18-1.72, P = 0.0002) in Quartile 1 (≤0.47 mmol/L), 1.20 (95%CI 1.00-1.44, P = 0.05) in Quartile 2 (0.47-0.66 mmol/L), and 1.25 (95%CI 1.05-1.49, P = 0.02) in Quartile 4 (>0.93 mmol/L). Higher risk was also observed for cardiovascular deaths in Quartile 1 (HR 1.66, 95%CI 1.15-2.41, P = 0.007), Quartile 2 (HR 1.39, 95%CI 0.97-2.00, P = 0.08), and Quartile 4 (HR 1.54, 95% CI 1.08-2.19, P = 0.02), as compared with Quartile 3. CONCLUSION: In US adults with diabetes, low and high levels of RC were associated with increased risks of all-cause and cardiovascular deaths, and the lowest risk was observed at RC level of 0.85 mmol/L. These findings suggested that maintaining appropriate RC level may help reduce risk of death in diabetic patients.

3.
BMC Anesthesiol ; 23(1): 402, 2023 12 07.
Artículo en Inglés | MEDLINE | ID: mdl-38062374

RESUMEN

BACKGROUND: Severe pain after lumbar spine surgery can delay recovery in elderly patients. We explored the efficacy of T12 erector spinal plane block (ESPB) in elderly patients who underwent lumbar spine surgery. METHODS: A total of 230 patients undergoing lumbar spine surgery were divided and randomly allocated to ultrasound-guided ESPB (n = 115) and control (n = 115) groups. The ESPB group received 20 mL of 0.4% ropivacaine bilaterally at the T12 level after intubation, whereas the control group did not receive a block. The primary outcome was the numeric rating scale (NRS) score at 12 h after surgery. Secondary outcomes included the NRS score and tramadol use within 72 h postoperatively, intraoperative remifentanil use, incidence of postoperative delirium (POD), complications of ESPB, ambulation time, and length of hospitalization after surgery. RESULTS: The12-hour NRS (median (IQR)) score was remarkably lower in the ESPB group than in the control group (2 (1-3) vs. 3 (2-4), p = 0.004), as well as NRS score within 48 h (P < 0.01). The ESPB group had less intraoperative remifentanil use (P < 0.001), and less tramadol use within 72 h postoperatively (P < 0.001). Seven patients (6.7%) developed POD in the ESPB group and ten patients (9.3%) in the control group, without any statistically significant difference (P > 0.05). The ambulation time and length of hospitalization after surgery were shorter in the ESPB group than in the control group (P < 0.05). No ESPB-related complications were observed. CONCLUSIONS: Bilateral T12 ESPB lowered the NRS score within 48 h after lumbar spine surgery, decreased perioperative opioid use and resulted in faster recovery in elderly patients but did not significantly reduce the incidence of POD. TRIAL REGISTRATION: The study was retrospectively registered at www.chictr.org.cn (ChiCTR2100042037) on January 12, 2021.


Asunto(s)
Analgesia , Delirio del Despertar , Bloqueo Nervioso , Tramadol , Anciano , Humanos , Remifentanilo , Método Simple Ciego , Tramadol/uso terapéutico , Vértebras Torácicas/cirugía , Dolor Postoperatorio/tratamiento farmacológico , Dolor Postoperatorio/prevención & control , Ultrasonografía Intervencional , Analgésicos Opioides/uso terapéutico
4.
Arch Orthop Trauma Surg ; 143(3): 1429-1440, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-35066642

RESUMEN

INTRODUCTION: The aim of this study was to determine whether the sagittal lordotic alignment, clinical outcomes and axial symptoms (AS) could be improved by kyphotic correction through the posterior approach for the treatment of multilevel cervical degenerative myelopathy (CDM) and to further analyze the changes of cervical spinal alignment parameters after correction of kyphosis. The hypothesis was that correction of kyphosis can improve the severity of AS and neurological recovery. MATERIALS AND METHODS: We retrospectively reviewed 109 patients who suffered from multilevel CDM combined with kyphosis. The patients had undergone open-door laminoplasty (Group LP, 53 patients) and laminectomy with instrumentation (Group LI, 56 patients) between January 2014 and December 2018. Cervical spinal alignment parameters, including curvature index (CI), T1 slope, C2-7 Cobb angle, C2-7 SVA, were measured on the pre- and postoperative lateral radiographs. The recovery rate was calculated based on the Japanese Orthopedic Association (JOA) score. AS severity was quantified using Neck Disability Index (NDI). A P value less than 0.05 was considered to be significant. RESULTS: Analyses of postoperative follow-up data showed significant differences (P < 0.001) in CI, correction of CI, C2-7 Cobb angle, T1 slope, C2-7 SVA and NDI between Group LP and LI, but no significant differences in JOA score (P = 0.23) and recovery rate (P = 0.13). There were significant differences (P < 0.001) in CI, T1 slope, C2-7 Cobb angle, C2-7 SVA, JOA score, and NDI between pre- and postoperative follow-up in both groups. Correction of CI showed negative correlation with AS severity (r = -0.51, P < 0.001), and no association with recovery rate (r = 0.14, P = 0.15). CONCLUSIONS: Satisfied neurological improvement was achieved by LP and LI for multilevel CDM combined with kyphosis. Cervical kyphotic correction produced significant improvement of AS and increase of T1 slope and C2-7 SVA. However, the kyphotic correction may not be associated with better neurological recovery in the short-term postoperative period.


Asunto(s)
Cifosis , Laminoplastia , Enfermedades de la Médula Espinal , Humanos , Laminectomía , Estudios Retrospectivos , Vértebras Cervicales/cirugía , Resultado del Tratamiento , Enfermedades de la Médula Espinal/cirugía , Cifosis/cirugía
5.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 40(9): 1146-1149, 2023 Sep 10.
Artículo en Zh | MEDLINE | ID: mdl-37643963

RESUMEN

OBJECTIVE: To explore the clinical characteristics and genetic etiology of a patient with mental retardation and ejaculatory dysfunction. METHODS: A patient with mental retardation and ejaculatory dysfunction who was admitted to the First Affiliated Hospital of Air Force Military Medical University on November 18, 2021 was selected as the study subject. Clinical data of the patient were collected. Peripheral venous blood samples were collected from the patient and his parents. Whole exome sequencing (WES) was carried out for the patient, and the candidate variant was verified by Sanger sequencing and bioinformatic analysis. RESULTS: The patient, a 26-year-old male, had manifested atypical mental retardation and ejaculatory dysfunction. WES revealed that he has harbored a heterozygous variant of the ARID1B gene, namely c.5776C>T (p.Arg1926X). Sanger sequencing verified that neither of his parents has carried the same variant. The variant has been recorded in the 1000 Genomes, ExAC, gnomAD and ClinVar databases. A search of the dbSNP database suggested that the variant has a population frequency of 0.000 4%. The variant was predicted as deleterious by online software including Mutation Taster, CADD, and MutPred. Analysis with Cluster Omega online software suggested that the amino acid encoded by the variant site was highly conserved among various species. Analysis with PyMOL software suggested that the variant may affect the function of the encoded protein. Based on the guidelines from the American College of Medical Genetics and Genomics (ACMG) and ClinGen, the variant was predicted to be pathogenic. CONCLUSION: The c.5776C>T (p.Arg1926X) variant of the ARID1B gene probably underlay the mental retardation and ejaculatory dysfunction in this patient. Above finding has broadened the spectrum of the ARID1B gene variants and provided reference for the diagnosis and treatment of the patient.


Asunto(s)
Discapacidad Intelectual , Masculino , Humanos , Adulto , Discapacidad Intelectual/genética , Factores de Transcripción/genética , Biología Computacional , Frecuencia de los Genes , Genómica , Proteínas de Unión al ADN/genética
6.
Immunol Invest ; 51(6): 1895-1907, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35921125

RESUMEN

BACKGROUND: The present study was designed to identify and understand the potential effectiveness of therapeutic target in intervertebral disc degeneration (IVDD) and its regulation mechanism. METHODS: The role and mechanism of interleukin-18 (IL-18) in the disease were investigated. The IVDD degenerative nucleus pulposus (NP) tissues from the human and mouse models were used.A total of three groups of Male BALB/c mice were randomly made i.e control, IVDD, and IVDD+Ad-shIL-18 groups. After Ad-shIL-18 transfection, the expression of ECM synthesis related protein Aggrecan (ACAN) and Collagen II, apoptotic effector Caspases (Caspase-3, 8, 9, 12 and Cleaved-Caspase 3, 8, 9, 12), pro-apoptotic gene Bax and anti-apoptotic factors Bcl-2 in NP cells of the human were evaluated. RESULTS: The results of our study revealed that the mRNA and protein expression levels of IL-18 were notably increased in the NP tissues of IVDD patients and mice models. In the IVDD mice model, Ad-sh-IL-18 treatment reversed the IVDD progression. The levels of Aggrecan and Collagen II, contributing to ECM degradation in NP cells, were also significantly increased. Additionally, Ad-sh-IL-18 could inhibit the NP cell's apoptosis via regulating the caspase-3/9 pathway. CONCLUSION: The IL-18 knockdown via the caspase-3/9 pathway, might reduce the NP cell's death as well as the imbalance between catabolism and anabolism of ECM in IVDD.


Asunto(s)
Degeneración del Disco Intervertebral , Agrecanos/genética , Animales , Apoptosis , Caspasa 3/genética , Colágeno/uso terapéutico , Humanos , Interleucina-18 , Degeneración del Disco Intervertebral/tratamiento farmacológico , Degeneración del Disco Intervertebral/genética , Degeneración del Disco Intervertebral/metabolismo , Masculino , Ratones
7.
Acta Neurol Scand ; 145(4): 434-441, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-34927233

RESUMEN

BACKGROUND: The factors associated with anti-N-methyl-D-aspartate (NMDA) receptor encephalitis relapse are yet to be elucidated. AIMS OF THE STUDY: To investigate the factors associated with relapse and prognosis of anti-NMDA receptor encephalitis. METHODS: This retrospective study included patients diagnosed with anti-NMDA receptor encephalitis admitted to the First Affiliated Hospital of Zhengzhou University from January 2013 to October 2019. The clinical features, auxiliary examinations, treatment regimens, and follow-up were recorded. The outcomes were relapse and 2-year disease prognosis. RESULTS: A total of 160 patients were included. Consequently, 6 (5%) deaths, 34 (25.4%) relapses, and 19 (15.2%) patients had a poor prognosis (modified Rankin score (mRS) ≥3) were recorded. The multivariable analyses showed that age (p = .011), abnormal magnetic resonance imaging (MRI) (p = .019), glucocorticoid pulse (p = .009), and intracranial pressure (p = .023) were independently associated with the relapse, while age (p = .030) and central hypoventilation (p = .020) were independently associated with a poor prognosis at 2 years. CONCLUSION: Glucocorticoid pulse therapy reduces the relapse of anti-NMDA receptor encephalitis. Age, abnormal MRI, and intracranial pressure are risk factors for relapse, while age and central hypoventilation are independently associated with poor prognosis.


Asunto(s)
Encefalitis Antirreceptor N-Metil-D-Aspartato , Encefalitis Antirreceptor N-Metil-D-Aspartato/diagnóstico , Encefalitis Antirreceptor N-Metil-D-Aspartato/diagnóstico por imagen , Preescolar , Humanos , Imagen por Resonancia Magnética , Recurrencia Local de Neoplasia/complicaciones , Receptores de N-Metil-D-Aspartato , Estudios Retrospectivos
8.
J Transl Med ; 19(1): 431, 2021 10 16.
Artículo en Inglés | MEDLINE | ID: mdl-34656132

RESUMEN

BACKGROUND: High morbidity and mortality due to carbapenem-resistant Gram-negative bacilli (CR-GNB) has led to the resurgence of polymyxin B (PMB) use in the last decade. The aim of our multicenter, real-world study was to evaluate the effectiveness and safety of PMB in the treatment of CR-GNB infections. METHODS: The real-world study included patients treated with intravenous PMB for at least 7 days during the period of October 2018 through June 2019. Associations between these clinical features and 28-day mortality or all-cause hospital mortality were explored through univariate analyses and multivariable logistic regression. RESULTS: The study included 100 patients. Many patients presented with combined chronic conditions, septic shock, mechanical ventilation, and the presence of Klebsiella pneumoniae. The mean duration of PMB therapy was 11 days (range 7-38 days). Temperature (38 °C vs 37.1 °C), white blood cells (14.13 × 109/l vs 9.28 × 109/l), C-reactive protein (103.55 ug/l vs 47.60 ug/l), procalcitonin (3.89 ng/ml vs 1.70 ng/ml) and APACHE II levels (17.75 ± 7.69 vs 15.98 ± 7.95) were significantly decreased after PMB treatment. The bacteria eradication rate was 77.65%. The overall mortality at discharge was 15%, and 28-day mortality was 40%. Major adverse reactions occurred in 16 patients. Nephrotoxicity was observed in 7 patients (7%). CONCLUSIONS: Our results provide positive clinical and safety outcomes for PMB in the treatment of CR-GNB. Timely and appropriate use of PMB may be particularly useful in treating patients with sepsis in CR-GNB infections.


Asunto(s)
Infecciones por Bacterias Gramnegativas , Polimixina B , Antibacterianos/efectos adversos , Carbapenémicos/efectos adversos , Bacterias Gramnegativas , Infecciones por Bacterias Gramnegativas/tratamiento farmacológico , Humanos , Polimixina B/efectos adversos
9.
Chem Soc Rev ; 49(15): 5310-5358, 2020 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-32568340

RESUMEN

Direct C-H bond functionalization catalyzed by non-precious transition metals is an attractive strategy in synthetic chemistry. Compared with the precious metals rhodium, palladium, ruthenium, and iridium commonly used in this field, catalysis based on non-precious metals, especially the earth-abundant ones, is appealing due to the increasing demand for environmentally benign and sustainable chemical processes. Herein, developments in iron- and cobalt-catalyzed C(sp3)-H bond functionalization reactions are described, with an emphasis on their applications in organic synthesis, i.e., the synthesis of natural products and pharmaceuticals and/or their modification.


Asunto(s)
Productos Biológicos/síntesis química , Cobalto/química , Complejos de Coordinación/química , Hierro/química , Aminación , Catálisis , Técnicas de Química Sintética , Técnicas Electroquímicas , Enlace de Hidrógeno , Hidroxilación , Ligandos , Estructura Molecular , Oxidación-Reducción , Procesos Fotoquímicos
10.
Angew Chem Int Ed Engl ; 60(9): 4796-4803, 2021 02 23.
Artículo en Inglés | MEDLINE | ID: mdl-33205509

RESUMEN

High-valent iron-nitrido species are nitrogen analogues of iron-oxo species which are versatile reagents for C-H oxidation. Nonetheless, C-H activation by iron-nitrido species has been scarcely explored, as this is often hampered by their instability and short lifetime in solutions. Herein, the hydrogen atom transfer (HAT) reactivity of an Fe porphyrin nitrido species (2 c) toward C-H substrates was studied in solutions at room temperature, which was achieved by nanosecond laser flash photolysis (LFP) of its FeIII -azido precursor (1 c) supported by a bulky bis-pocket porphyrin ligand. C-H bonds with bond dissociation enthalpies (BDEs) of up to ≈84 kcal mol-1 could be activated, and the second-order rate constants (k2 ) are on the order of 102 -104  s-1 m-1 . The Fe-amido product formed after HAT could further release ammonia upon protonation.

11.
Angew Chem Int Ed Engl ; 60(50): 26072-26079, 2021 Dec 06.
Artículo en Inglés | MEDLINE | ID: mdl-34545677

RESUMEN

A bis(pyridyl)amine-bipyridine-iron(II) framework (Fe(BPAbipy)) of complexes 1-3 is reported to shed light on the multistep nature of CO2 reduction. Herein, photocatalytic conversion of CO2 to CO even at low CO2 concentration (1 %), together with detailed mechanistic study and DFT calculations, reveal that 1 first undergoes two sequential one-electron transfer affording an intermediate with electron density on both Fe and ligand for CO2 binding over proton. The following 2 H+ -assisted Fe-CO formation is rate-determining for selective CO2 -to-CO reduction. A pendant, proton-shuttling α-OH group (2) initiates PCET for predominant H2 evolution, while an α-OMe group (3) cancels the selectivity control for either CO or H2 . The near-unity selectivity of 1 and 2 enables self-sorting syngas production at flexible CO/H2 ratios. The unprecedented results from one kind of molecular catalyst skeleton encourage insight into the beauty of advanced multi-electron and multi-proton transfer processes for robust CO2 RR by photocatalysis.

12.
Angew Chem Int Ed Engl ; 59(5): 1845-1850, 2020 Jan 27.
Artículo en Inglés | MEDLINE | ID: mdl-31755156

RESUMEN

Described herein is an IrIII /porphyrin-catalyzed intermolecular C(sp3 )-H insertion reaction of a quinoid carbene (QC). The reaction was designed by harnessing the hydrogen-atom transfer (HAT) reactivity of a metal-QC species with aliphatic substrates followed by a radical rebound process to afford C-H arylation products. This methodology is efficient for the arylation of activated hydrocarbons such as 1,4-cyclohexadienes (down to 40 min reaction time, up to 99 % yield, up to 1.0 g scale). It features unique regioselectivity, which is mainly governed by steric effects, as the insertion into primary C-H bonds is favored over secondary and/or tertiary C-H bonds in the substituted cyclohexene substrates. Mechanistic studies revealed a radical mechanism for the reaction.

13.
Angew Chem Int Ed Engl ; 59(38): 16561-16571, 2020 09 14.
Artículo en Inglés | MEDLINE | ID: mdl-32500643

RESUMEN

Reliable methods for enantioselective cis-dihydroxylation of trisubstituted alkenes are scarce. The iron(II) complex cis-α-[FeII (2-Me2 -BQPN)(OTf)2 ], which bears a tetradentate N4 ligand (Me2 -BQPN=(R,R)-N,N'-dimethyl-N,N'-bis(2-methylquinolin-8-yl)-1,2-diphenylethane-1,2-diamine), was prepared and characterized. With this complex as the catalyst, a broad range of trisubstituted electron-deficient alkenes were efficiently oxidized to chiral cis-diols in yields of up to 98 % and up to 99.9 % ee when using hydrogen peroxide (H2 O2 ) as oxidant under mild conditions. Experimental studies (including 18 O-labeling, ESI-MS, NMR, EPR, and UV/Vis analyses) and DFT calculations were performed to gain mechanistic insight, which suggested possible involvement of a chiral cis-FeV (O)2 reaction intermediate as an active oxidant. This cis-[FeII (chiral N4 ligand)]2+ /H2 O2 method could be a viable green alternative/complement to the existing OsO4 -based methods for asymmetric alkene dihydroxylation reactions.

14.
J Cell Physiol ; 234(11): 20859-20868, 2019 11.
Artículo en Inglés | MEDLINE | ID: mdl-30997686

RESUMEN

Vascular invasion (VI) in hepatocellular carcinoma (HCC) is an important clinical parameter to predict survival. In this study, we collected microRNA (miRNA) expression data from HCC patients using The Cancer Genome Atlas database and identified a novel miRNA signature associated with VI. First, we categorized HCC patients into groups with or without VI (VI+ and VI-). We identified three miRNAs (miRNA-210, miRNA-10b, and miRNA-9-1) that were associated with VI according to a Kaplan-Meier analysis. This three-miRNA signature exhibited good predictive ability for VI in patients with HCC according to a receiver operating characteristic curve analysis at 1, 3, and 5 years. Patients with HCC with a high risk score exhibited a trend toward worse outcomes as determined by multivariable Cox regression and stratified analyses. This three-miRNA signature provides an accurate prediction of VI and can be used as an independent prognostic indicator for predicting VI in HCC patients.


Asunto(s)
Carcinoma Hepatocelular/irrigación sanguínea , Carcinoma Hepatocelular/genética , Perfilación de la Expresión Génica , Neoplasias Hepáticas/irrigación sanguínea , Neoplasias Hepáticas/genética , MicroARNs/metabolismo , Neovascularización Patológica/genética , Animales , Proliferación Celular/genética , Regulación Neoplásica de la Expresión Génica , Células Hep G2 , Humanos , Estimación de Kaplan-Meier , Ratones Desnudos , MicroARNs/genética , Pronóstico , Reproducibilidad de los Resultados , Factores de Riesgo , Análisis de Supervivencia
15.
J Am Chem Soc ; 141(22): 9027-9046, 2019 06 05.
Artículo en Inglés | MEDLINE | ID: mdl-31064182

RESUMEN

Reactivity study of novel metal carbene complexes can offer new opportunities in catalytic carbene transfer reactions as well as in other synthetic protocols. Metal complexes with quinoid carbene (QC) ligands are assumed to be key intermediates in a variety of metal-catalyzed QC transfer reactions using diazo quinones, which demands development of the chemistry of QC transfer of well characterized metal-QC complexes. Herein we report the isolation and QC transfer of ruthenium porphyrins [Ru(Por)(QC)] which contribute the first examples of (i) structurally characterized metal-QC complex (by X-ray crystallography) and (ii) isolated metal-QC complex that undergoes QC transfer reaction. The complexes [Ru(Por)(QC)] were prepared from reaction of [Ru(Por)(CO)] with diazo quinones and exhibited dual reactivity, i.e., hydrogen atom transfer (HAT) as well as QC transfer. The stoichiometric QC transfer reactions from these Ru-QC complexes to nitrosoarenes (ArNO) afforded nitrones in up to 90% yield, and the corresponding catalytic reactions were also developed. Both the stoichiometric and catalytic reactions for a series of QC ligands bearing electron-donating and -withdrawing substituents showed a reverse substituent effect on the QC transfer reactivity. Complexes [Ru(Por)(QC)] are also reactive toward C-H and X-H (X = N, S) bonds and can catalyze aerobic oxidation of 1,4-cyclohexadiene; their stoichiometric HAT reactions with unsaturated hydrocarbons gave product yields of up to 88%. The unique dual reactivity and electronic feature of [Ru(Por)(QC)] were studied by spectroscopic means and density functional theory (DFT) calculations.

16.
Med Sci Monit ; 24: 2384-2390, 2018 Apr 20.
Artículo en Inglés | MEDLINE | ID: mdl-29674607

RESUMEN

BACKGROUND Increasing evidence indicates that long noncoding RNAs (LncRNAs) play a key role in multiple pathological processes. It has been shown that LncRNA steroid receptor RNA activator (SRA) is elevated in peripheral blood of patients with polycystic ovary syndrome (PCOS). The aim of this study was to assess the effect of elevated LncRNA SRA on ovarian granular cells of mice in vitro. MATERIAL AND METHODS We firstly isolated granular cells from mouse ovaries and over-expressed the LncRNA SRA by means of lentiviral transfection in this cell line. Then, we assessed the effects of LncRNA SRA on granular cells through real-time PCR, CCK-8 assay, flow cytometry, Hoechst staining, and Western blot assay. RESULTS We demonstrated that elevated LncRNA SRA stimulated cell growth, changed distribution of cell cycle phases with increase of Cyclin B, Cyclin E, and Cyclin D1, and inhibited cell apoptosis with up-regulation of bcl2 and down-regulation of bax, cleaved-caspase 3, and cleaved-PARP. Moreover, the contents of estradiol (E2) and progesterone (PG) and expressions of their key enzymes (CYP19A1 and CYP11A1) were up-regulated following over-expression of LncRNA SRA. CONCLUSIONS Taken together, our results indicate that abnormal LncRNA SRA may be a risk factor for evoking PCOS.


Asunto(s)
Síndrome del Ovario Poliquístico/genética , ARN Largo no Codificante/metabolismo , Animales , Apoptosis/genética , Ciclo Celular/genética , División Celular/genética , Movimiento Celular/genética , Proliferación Celular/genética , Estradiol/genética , Estradiol/metabolismo , Femenino , Regulación Neoplásica de la Expresión Génica/genética , Tumor de Células Granulares/genética , Tumor de Células Granulares/metabolismo , Células de la Granulosa/metabolismo , Células de la Granulosa/fisiología , Ratones , Ovario/metabolismo , Ovario/fisiología , Síndrome del Ovario Poliquístico/metabolismo , Cultivo Primario de Células , Progesterona/genética , Progesterona/metabolismo , ARN Largo no Codificante/genética , Activación Transcripcional/genética , Regulación hacia Arriba
17.
Chaos ; 25(4): 043108, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25933656

RESUMEN

Reliable signal propagation across distributed brain areas is an essential requirement for cognitive function, and it has been investigated extensively in computational studies where feed-forward network (FFN) is taken as a generic model. But it is still unclear how distinct local network states, which are intrinsically generated by synaptic interactions within each layer, would affect the ability of FFN to transmit information. Here we investigate the impact of such network states on propagating transient synchrony (synfire) and firing rate by a combination of numerical simulations and analytical approach. Specifically, local network dynamics is attributed to the competition between excitatory and inhibitory neurons within each layer. Our results show that concomitant with different local network states, the performance of signal propagation differs dramatically. For both synfire propagation and firing rate propagation, there exists an optimal local excitability state, respectively, that optimizes the performance of signal propagation. Furthermore, we find that long-range connections strongly change the dependence of spiking activity propagation on local network state and propose that these two factors work jointly to determine information transmission across distributed networks. Finally, a simple mean field approach that bridges response properties of long-range connectivity and local subnetworks is utilized to reveal the underlying mechanism.


Asunto(s)
Redes Neurales de la Computación , Neuronas/patología , Procesamiento de Señales Asistido por Computador , Potenciales de Acción/fisiología , Algoritmos , Animales , Encéfalo/fisiología , Cognición , Simulación por Computador , Humanos , Modelos Neurológicos , Modelos Teóricos , Red Nerviosa/fisiología , Neuronas/metabolismo , Neuronas/fisiología , Distribución Normal , Relación Señal-Ruido , Transmisión Sináptica/fisiología
18.
Int J Biol Macromol ; 267(Pt 2): 131726, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38688791

RESUMEN

The characteristics of multi-hydroxyl structure and strong hydrogen bonding in polyvinyl alcohol (PVA) make its melting point close to its decomposition temperature, causing melt-processing difficulty. In this work, following the plasticization of small-molecule primary plasticizer acetamide, lignin was demonstrated as a green secondary plasticizer in realizing the melt processing and simultaneous reinforcement of PVA. During the plasticization process, lignin was able to combine with the hydroxyl groups of PVA, so as to destroy the hydrogen bonds and regularity of the PVA chains. The synergistic plasticization effect of lignin dramatically reduced the melting point of PVA from 185 °C to 151 °C. The thermal processing window of PVA composites was expanded from 50 °C to roughly 80 °C after introducing lignin. In contrast to acetamide, the addition of lignin significantly increased the tensile strength and Young's modulus of the composites to 71 MPa and 1.34 GPa, respectively. Meanwhile, lignin helped to hinder the migration of acetamide via hydrogen bonds. With the addition of lignin, the composites also displayed enhanced hydrophobicity and excellent UV shielding performance. The strategy of synergistic plasticization of lignin provides a feasible basis for the practical application of lignin in melt-processable PVA materials with good comprehensive properties.


Asunto(s)
Lignina , Plastificantes , Alcohol Polivinílico , Resistencia a la Tracción , Lignina/química , Alcohol Polivinílico/química , Plastificantes/química , Enlace de Hidrógeno , Temperatura , Módulo de Elasticidad , Interacciones Hidrofóbicas e Hidrofílicas
19.
Front Microbiol ; 15: 1387679, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38919494

RESUMEN

Objectives: The incidence of oropharyngeal cancer (OPC) is increasing. This study used bibliometric analysis and topic modeling to explore the research trends and advancements in this disease over the past 10 years, providing valuable insights to guide future investigations. Methods: 7,355 English articles from 2013 to 2022 were retrieved from the Web of Science Core Collection for bibliometric analysis. Topic modeling was applied to 1,681 articles from high-impact journals, followed by an assessment of topic significance ranking (TSR). Medical Subject Headings (MeSH) terms were extracted using R and Python, followed by an analysis of the terms associated with each topic and on an annual basis. Additionally, genes were extracted and the number of genes appearing each year and the newly emerged genes were counted. Results: The bibliometric analysis suggested that the United States and several European countries hold pivotal positions in research. Current research is focused on refining treatments, staging and stratification. Topic modeling revealed 12 topics, emphasizing human papillomavirus (HPV) and side effect reduction. MeSH analysis revealed a growing emphasis on prognosis and quality of life. No new MeSH terms emerged after 2018, suggesting that the existing terms have covered most of the core concepts within the field of oropharyngeal cancers. Gene analysis identified TP53 and EGFR as the most extensively studied genes, with no novel genes discovered after 2019. However, CD69 and CXCL9 emerged as new genes of interest in 2019, reflecting recent research trends and directions. Conclusion: HPV-positive oropharyngeal cancer research, particularly treatment de-escalation, has gained significant attention. However, there are still challenges in diagnosis and treatment that need to be addressed. In the future, more research will focus on this issue, indicating that this field still holds potential as a research hotspot.

20.
Inflammation ; 2024 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-38302679

RESUMEN

Chronic diabetes mellitus compromises the vascular system, which causes organ injury, including in the lung. Due to the strong compensatory ability of the lung, patients always exhibit subclinical symptoms. Once sepsis occurs, the degree of lung injury is more severe under hyperglycemic conditions. The α7 nicotinic acetylcholine receptor (α7nAChR) plays an important role in regulating inflammation and metabolism and can improve endothelial progenitor cell (EPC) functions. In the present study, lung injury caused by sepsis was compared between diabetic rats and normal rats. We also examined whether α7nAChR activation combined with EPC transplantation could ameliorate lung injury in diabetic sepsis rats. A type 2 diabetic model was induced in rats via a high-fat diet and streptozotocin. Then, a rat model of septic lung injury was established by intraperitoneal injection combined with endotracheal instillation of LPS. The oxygenation indices, wet-to-dry ratios, and histopathological scores of the lungs were tested after PNU282987 treatment and EPC transplantation. IL-6, IL-8, TNF-α, and IL-10 levels were measured. Caspase-3, Bax, Bcl-2, and phosphorylated NF-κB (p-NF-κB) levels were determined by blotting. Sepsis causes obvious lung injury, which is exacerbated by diabetic conditions. α7nAChR activation and endothelial progenitor cell transplantation reduced lung injury in diabetic sepsis rats, alleviating inflammation and decreasing apoptosis. This treatment was more effective when PNU282987 and endothelial progenitor cells were administered together. p-NF-κB levels decreased following treatment with PNU282987 and EPCs. In conclusion, α7nAChR activation combined with EPC transplantation can alleviate lung injury in diabetic sepsis rats through the NF-κB signaling pathway.

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