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1.
Angew Chem Int Ed Engl ; 63(16): e202401706, 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38419479

RESUMEN

Rigid three-dimensional (3D) polycyclic propellanes have garnered interest due to their unique conformational spaces, which display great potential use in selectivity, separation and as models to study through-space electronic interactions. Herein we report the synthesis of a novel rigid propellane, trinaphtho[3.3.3]propellane triimide, which comprises three imide groups embedded on a trinaphtho[3.3.3]propellane. This propellane triimide exhibits large bathochromic shift, amplified molar absorptivity, enhanced fluorescence, and lower reduction potential when compared to the subunits. Computational and experimental studies reveal that the effective through-space π-orbitals interacting (homoconjugation) occurs between the subunits. Single-crystal XRD analysis reveals that the propellane triimide has a highly quasi-D3h symmetric skeleton and readily crystallizes into different superstructures by changing alkyl chains at the imide positions. In particular, the porous 3D superstructure with S-shaped channels is promising for taking up ethane (C2H6) with very good selectivity over ethylene (C2H4), which can purify C2H4 from C2H6/C2H4 in a single separation step. This work showcases a new class of rare 3D polycyclic propellane with intriguing electronic and supramolecular properties.

2.
BMC Med ; 20(1): 487, 2022 12 17.
Artículo en Inglés | MEDLINE | ID: mdl-36527023

RESUMEN

BACKGROUND: Sacubitril/valsartan and angiotensin-converting enzyme inhibitor (ACEI)/angiotensin-receptor blocker (ARB) therapies were reported to affect glycaemic control and the development of diabetes mellitus (DM), but the findings are inconsistent. We examined the evidence for the effects of sacubitril/valsartan and ACEI/ARB in DM by conducting a meta-analysis. METHODS: The Cochrane Central Register of Controlled Trials (The Cochrane Library), Embase, PubMed, and ClinicalTrials.gov were searched for data from randomised clinical trials (RCTs) that evaluated the efficacy of sacubitril/valsartan and ACEI/ARB in patients, as of May 25, 2022. Patients were grouped by their disease background at baseline. The main outcomes were the number of new-onset DM and hypoglycaemia, elevated glycaemia, inadequate DM control, diabetes treatment, and diabetic complications, from baseline to the end of the trials. The risk of bias was assessed using the revised Cochrane risk-of-bias tool for randomized trials (ROB 2). The quality of the evidence was evaluated according to the Recommendations for Assessment, Development, and Evaluation guidelines. The meta-analysis of the incidence of various outcomes was conducted using fixed or random effects models. The results are expressed as binary risk, 95% confidence interval (CI), and relative risk (RR). The Mantel-Haenszel method and Z test were used to determine the overall results and determine the significance of the RR. RESULTS: This study included 31 RCTs and 86,809 subjects. Compared with placebo, sacubitril/valsartan treatment significantly reduced the risk of new-onset DM among all patients (RR = 0.78, 95% CI: 0.64-0.95), patients with heart failure (HF) (RR = 0.24, 95% CI: 0.12-0.48), HF with reduced ejection fraction (HFrEF) (RR = 0.24, 95% CI: 0.12-0.50), and HF with preserved ejection fraction (HFpEF) (RR = 0.54, 95% CI 0.34-0.85). In contrast, sacubitril/valsartan treatment significantly increased the risk of hypoglycaemia among all patients (RR = 1.91, 95% CI: 1.05-3.47), patients with not all-DM (defined as part of the study population having DM at baseline) (RR = 5.71, 95% CI: 2.02-16.21), and patients with HFpEF (RR = 7.06, 95% CI: 2.10-23.76). Compared with ACEI/ARB, sacubitril/valsartan treatment significantly increased the risk of hypoglycaemia among patients with HF (RR 1.85, 95% CI 1.12-3.06, p = 0.02) and HFpEF (RR 3.59, 95% CI 1.51-8.55, p = 0.004). Compared with placebo, ACEI/ARB treatment did significantly reduce the risk of new-onset DM among all patients (RR 0.85, 95% CI 0.77-0.93, p = 0.0007) and patients with not all-HF (defined as part of the study population having HF at baseline) (RR 0.87, 95% CI 0.82-0.93, p<0.0001) and HFpEF (RR 0.60, 95% CI 0.44-0.83, p = 0.002), diabetes complications among patients with non-HF (/not all-DM) (RR 0.87, 95% CI 0.76-0.99, p = 0.04), and subsequent diabetes treatment among patients with new-onset DM (RR 0.70, 95% CI 0.58-0.84, p = 0.0002) and significantly increased the risk of hypoglycaemia among patients with not all-DM (RR 2.06, 95% CI 1.172-3.61, p = 0.01). CONCLUSIONS: The results of our study, especially in reducing glycaemia and new-onset DM, revealed that sacubitril/valsartan had a positive effect on the control of glycaemia and the development of DM. ACEI/ARB also had a beneficial effect but the effect was weaker than that of sacubitril/valsartan. The above effects varied across diseases but the evidence was strongest in patients with HF. TRIAL REGISTRATION: CRD42022336311.


Asunto(s)
Diabetes Mellitus , Insuficiencia Cardíaca , Hipoglucemia , Humanos , Inhibidores de la Enzima Convertidora de Angiotensina/uso terapéutico , Antagonistas de Receptores de Angiotensina/efectos adversos , Tetrazoles/efectos adversos , Volumen Sistólico , Aminobutiratos/efectos adversos , Valsartán/farmacología , Valsartán/uso terapéutico , Insuficiencia Cardíaca/tratamiento farmacológico , Combinación de Medicamentos , Diabetes Mellitus/tratamiento farmacológico , Hipoglucemia/inducido químicamente , Hipoglucemia/tratamiento farmacológico , Ensayos Clínicos Controlados Aleatorios como Asunto
3.
Sensors (Basel) ; 21(3)2021 Jan 27.
Artículo en Inglés | MEDLINE | ID: mdl-33513856

RESUMEN

This paper presents a novel decentralized multi-robot collision avoidance method with deep reinforcement learning, which is not only suitable for the large-scale grid map workspace multi-robot system, but also directly processes Lidar signals instead of communicating between the robots. According to the particularity of the workspace, we handcrafted a reward function, which considers both the collision avoidance among the robots and as little as possible change of direction of the robots during driving. Using Double Deep Q-Network (DDQN), the policy was trained in the simulation grid map workspace. By designing experiments, we demonstrated that the learned policy can guide the robot well to effectively travel from the initial position to the goal position in the grid map workspace and to avoid collisions with others while driving.

4.
Gynecol Endocrinol ; 36(3): 218-221, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31650878

RESUMEN

Kallmann syndrome (KS) is a rare inherited disorder, which has significantly genotypic and phenotypic heterogeneity. KS is clinically characterized by the combination of hypogonadotropic hypogonadism and hypo/anosmia. At present, there is no relevant report that intron mutation in SEMA7A gene helps induce KS. A 17-year-old Chinese female (46, XX) came to our department due to primary amenorrhea, who actually had hyposmia since her childhood. Hypogonadotropic hypogonadism was then detected. Luteinizing hormone (LH) and follicle-stimulating hormone (FSH) levels were remarkably low. And estradiol level was extremely low. The laboratory test results were consistent with KS. A heterozygous point mutation of intron 13 in SEMA7A (NM_003612.3:c.1640-3C > A) was identified. The patient received the treatment of pulsatile gonadotropin-releasing hormone (GnRH) pump, which could imitate physiological ovarian stimulation, thus resulting in mature follicle and a peak of LH. The patient was injected subcutaneously every 90 min with a dose of 10 µg per pulse, which had bona efficacy. She acquired menarche at about 43 days after the treatment. We firstly report a case of KS caused by a novel mutation site in the intron of SEMA7A gene. We mainly provide insight into the clinical manifestations, genetic diagnosis and treatment of KS.


Asunto(s)
Antígenos CD/genética , Síndrome de Kallmann/genética , Semaforinas/genética , Adolescente , Amenorrea/etiología , Anosmia/etiología , Padre , Femenino , Hormona Folículo Estimulante/sangre , Proteínas Ligadas a GPI/genética , Hormona Liberadora de Gonadotropina/uso terapéutico , Heterocigoto , Humanos , Intrones , Síndrome de Kallmann/complicaciones , Síndrome de Kallmann/diagnóstico , Síndrome de Kallmann/tratamiento farmacológico , Hormona Luteinizante/sangre , Imagen por Resonancia Magnética , Mutación , Bulbo Olfatorio/diagnóstico por imagen , Bulbo Olfatorio/patología , Tamaño de los Órganos , Hipófisis/diagnóstico por imagen , Hipófisis/patología , Quimioterapia por Pulso , Secuenciación del Exoma
5.
Gynecol Endocrinol ; 35(5): 385-389, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-30614301

RESUMEN

17α-Hydroxylase/17,20-lyase deficiency (17-OHD) is a rare disease caused by mutations of the CYP17A1 gene. Slipped capital femoral epiphysis (SCFE) rarely occurs in adults. There are occasional reports of adrenal myelolipoma (AML) in 17-OHD. A 27-year-old Chinese female (46, XX) visited the hospital for SCFE and presented with continuous hypokalemia, absent spontaneous puberty, and hypertension. Hypergonadotropic hypogonadism was detected. The laboratory tests were consistent with 17-OHD. AML was considered based on the imaging examinations. A mutation analysis of the CYP17A1 gene identified the following compound heterozygous mutation: a frame-shift mutation, i.e. c.985_987delTACinsAA (p.Tyr329fs), that had been reported to be a common mutation in the Chinese population was found in exon 6. Another new nonsense mutation, i.e. c.1270C > T (p.Gln424*), that causes a premature termination codon was found in exon 8. Treatment with prednisone had poor efficacy. The administration of 0.75 mg dexamethasone and estradiol/dydrogesterone cyclic treatment significantly improved the patient's symptoms. For the first time, we report a 17-OHD case accompanied by SCFE, AML, and a novel mutation site in the CYP17A1 gene. We provide insight into the clinical manifestations, genetic analysis, and treatment options of 17-OHD.


Asunto(s)
Neoplasias de las Glándulas Suprarrenales/genética , Hiperplasia Suprarrenal Congénita/genética , Mutación , Mielolipoma/genética , Epífisis Desprendida de Cabeza Femoral/genética , Esteroide 17-alfa-Hidroxilasa/genética , Adulto , Femenino , Humanos
6.
Sci Bull (Beijing) ; 69(13): 2089-2098, 2024 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-38777681

RESUMEN

Tactile sensing provides robots the ability of object recognition, fine operation, natural interaction, etc. However, in the actual scenario, robotic tactile recognition of similar objects still faces difficulties such as low efficiency and accuracy, resulting from a lack of high-performance sensors and intelligent recognition algorithms. In this paper, a flexible sensor combining a pyramidal microstructure with a gradient conformal ionic gel coating was demonstrated, exhibiting excellent signal-to-noise ratio (48 dB), low detection limit (1 Pa), high sensitivity (92.96 kPa-1), fast response time (55 ms), and outstanding stability over 15,000 compression-release cycles. Furthermore, a Pressure-Slip Dual-Branch Convolutional Neural Network (PSNet) architecture was proposed to separately extract hardness and texture features and perform feature fusion. In tactile experiments on different kinds of leaves, a recognition rate of 97.16% was achieved, and surpassed that of human hands recognition (72.5%). These researches showed the great potential in a broad application in bionic robots, intelligent prostheses, and precise human-computer interaction.

7.
Acta Pharm Sin B ; 12(1): 1-17, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-35127369

RESUMEN

Diabetic mellitus (DM) is a common degenerative chronic metabolic disease often accompanied by severe cardiovascular complications (DCCs) as major causes of death in diabetic patients with diabetic cardiomyopathy (DCM) as the most common DCC. The metabolic disturbance in DCM generates the conditions/substrates and inducers/triggers and activates the signaling molecules and death executioners leading to cardiomyocyte death which accelerates the development of DCM and the degeneration of DCM to heart failure. Various forms of programmed active cell death including apoptosis, pyroptosis, autophagic cell death, autosis, necroptosis, ferroptosis and entosis have been identified and characterized in many types of cardiac disease. Evidence has also been obtained for the presence of multiple forms of cell death in DCM. Most importantly, published animal experiments have demonstrated that suppression of cardiomyocyte death of any forms yields tremendous protective effects on DCM. Herein, we provide the most updated data on the subject of cell death in DCM, critical analysis of published results focusing on the pathophysiological roles of cell death, and pertinent perspectives of future studies.

8.
Front Cardiovasc Med ; 9: 991621, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36277796

RESUMEN

Importance: Cardiac-specific death from radiation caused by radiation therapy (RT) in patients with malignant tumors has received extensive attention, however, little is known regarding the potential cardiotoxic effects of RT in patients with non-malignant tumors. Objectives and methods: In this study, we used the SEER data to explore the incidence of post-radiation cardiovascular complications in patients with non-malignant tumors of central nervous system (CNS), and identify the influencing factors of cardiac-specific death. Results: Ultimately 233, 306 patients were included (97.8% of patients had brain tumors and 2.2% had spinal cord tumors). For patients with non-malignant tumors of CNS, RT {yes (odds ratio [OR] 0.851, 95% confidence interval [CI] 0.774-0.936, p = 0.001, before propensity score matching (PSM); OR 0.792, 95% CI 0.702-0.894, p < 0.001, after PSM) vs. no} was associated with lower risk of cardiac-specific death, other clinical features affecting cardiac death similar to those in patients with non-malignant tumors of CNS receiving RT. For patients with non-malignant tumors of CNS receiving RT, female, married status, Hispanic ethnicity, surgery, and tumor site (brain exclude nerve and endocrine, nervous system) were associated with lower risks of cardiac-specific death, while earlier year of diagnosis, older age of diagnosis, Black, larger tumor and bilateral tumor were risk factors for cardiac-specific death. Conclusions: Our study shows the influencing factors for cardiac-specific death in patients with non-malignant tumors of CNS, and found RT is associated with lower risk of cardiac-specific death. These results can facilitate the identification of patients with non-malignant tumors of CNS who can benefit from RT while avoiding cardiovascular events. In addition, this study helps to enhance the clinical use of RT in these populations, especially in patients who may have impaired cardiac function due to CNS tumors.

9.
Front Endocrinol (Lausanne) ; 13: 1049251, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36714586

RESUMEN

Diabetic cardiomyopathy (DCM) is a serious complication of diabetes mellitus that can cause malignant arrhythmia and sudden death and is associated with cardiomyocyte dysfunction induced by hyperglycemia. Emerging evidence has revealed that transfer RNA-derived fragments (tRFs), a novel class of noncoding RNAs, play a crucial role in a variety of pathophysiologic processes, including cell death, cell growth and proliferation. However, it remains unknown whether and how tRFs are involved in cardiomyocyte dysfunction during the progression of DCM. In this study, we found that cardiomyocyte abnormalities were induced by high glucose (HG) treatment, as demonstrated by a decrease in cell viability and autophagy activation as well as an increase in cell death and proinflammatory cytokine release. Moreover, HG treatment resulted in differential expression of tRFs in cardiomyocytes, of which 4 upregulated and 1 downregulated tRFs were observed compared with the control group. The differential expression of 4 upregulated tRFs was primarily involved in cardiac dysfunction-related processes, such as autophagy, AGE-RAGE signaling pathway in diabetic complications, MAPK signaling pathway, insulin signaling pathway, FoxO signaling pathway, insulin resistance and peroxisome pathways based on Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis. Furthermore, we found that tRF-5014a, the most significantly upregulated tRF among all tested tRFs, negatively regulated the expression of the autophagy-related protein ATG5. Importantly, inhibition of tRF-5014a not only abolished autophagy inactivation but also attenuated the decrease in cell viability and increase in cell death as well as proinflammatory cytokine release under HG conditions. These findings suggest that tRFs may contribute to HG-induced cardiomyocyte injury during DCM progression.


Asunto(s)
Miocitos Cardíacos , ARN de Transferencia , Miocitos Cardíacos/metabolismo , ARN de Transferencia/genética , ARN de Transferencia/metabolismo , ARN no Traducido/metabolismo , Sistema de Señalización de MAP Quinasas , Glucosa/farmacología , Glucosa/metabolismo
10.
J Pediatr Endocrinol Metab ; 33(2): 305-311, 2020 Feb 25.
Artículo en Inglés | MEDLINE | ID: mdl-31927522

RESUMEN

Background Familial hypophosphatemic rickets, which is usually acknowledged as X-linked hypophosphatemic rickets (XLH), is a rare hereditary disease. XLH caused by mutations in the PHEX gene often manifests as growth retardation, skeletal deformities, osteodynia and dental dysplasia. NPR2 mutations are reported to cause disproportionate short stature. Our study was designed to identify the gene mutations of three patients in one family. Case description A 40-year-old Chinese male visited the hospital for continuous osteodynia and presented with bilateral leg bowing, absent teeth and a progressive limp. The age of onset was approximately 2 years old. His 63-year-old mother and 42-year-old brother both shared identical symptoms with him. The laboratory tests were consistent with XLH, which showed decreased levels of blood phosphorus and 1,25-dihydroxyvitamin D3 as well as increased urinary phosphorus excretion. Mutation analysis revealed that the proband as well as his mother and his brother all had a PHEX mutation in exon 14 (c.1543C > T), and the proband also had a NPR2 mutation in exon 21 (c.3058C > T). Conclusions We report the familial hypophosphatemic rickets of three patients in a Chinese family caused by a PHEX gene mutation in exon 14 (c.1543C > T), which had never been reported in Chinese patients. We first report an XLH case together with a NPR2 mutation that had never been reported before.


Asunto(s)
Pueblo Asiatico/genética , Raquitismo Hipofosfatémico Familiar/etiología , Mutación , Endopeptidasa Neutra Reguladora de Fosfato PHEX/genética , Receptores del Factor Natriurético Atrial/genética , Adulto , Análisis Mutacional de ADN , Raquitismo Hipofosfatémico Familiar/patología , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Linaje , Pronóstico
11.
J Oleo Sci ; 66(5): 491-497, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28458387

RESUMEN

A systematic study on copper (II)-alginate beads as catalysts for the synthesis of biodiesel via esterification of oleic acid and methanol is here reported for the first time. The chemical structure and morphologies of these catalysts were fully characterized by XRD, FT-IR, and SEM. The copper (II)-alginate beads showed a tubular structure with entangled reticulation. In the presence of copper (II)-alginate catalyst, the biodiesel conversion of 71.8% was achieved from oleic acid with methanol under the most mild conditions (1/10 oleic acid to methanol molar ratio, 250 mg catalyst, 70°C for 3 h), optimized by single-factor experiments. The catalyst could be easily separated from the reaction mixture and stabilized for a certain time. This material can also catalyze other esterification of fatty acids with different carbon chain lengths, as well as the pretreatment of non-edible oils with high acid value. Our findings showed that the copper (II)-alginate is a suitable catalyst for esterification and would provide more choices for industrial application in the future.


Asunto(s)
Alginatos/química , Biocombustibles , Catálisis , Cobre/química , Ácido Oléico/química , Esterificación , Ácido Glucurónico/química , Ácidos Hexurónicos/química , Metanol/química , Estructura Molecular , Temperatura , Factores de Tiempo
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