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1.
Inorg Chem ; 62(31): 12329-12336, 2023 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-37478416

RESUMEN

Propyne/propylene separation is important in the petrochemical industry but challenging due to their similar physical properties and close molecular sizes. Metal-organic frameworks (MOFs) are a class of promising adsorbents for light hydrocarbon separations. Among them, the so-called "flexible-robust" MOFs combine the advantages of flexibility and rigidity in structure and could show enhanced gas separation selectivity as well as improved gas uptake at low pressure. Interpenetrated MOFs offer a platform to explore the "flexible-robust" feature of MOFs based on their subnetwork displacement in the process of gas adsorption. Herein, we present two hydrolytically stable MOFs (BUT-308 and BUT-309) with interpenetrated structures and fascinating propyne/propylene separation performance. BUT-308 is composed of interpenetrated 2D Cu(BDC-NH2)BPB layers (H2BDC-NH2 = 2-aminobenzene-1,4-dicarboxylic acid; BPB = 1,4-bis(4-pyridyl)benzene), while BUT-309 consists of twofold interpenetrated 3D pillared-layer Cu2(BDC-NH2)2(BPB-CF3) nets (BPB-CF3 = 2-trifluoromethyl-1,4-bis(4-pyridyl)benzene). Gas adsorption measurements showed that BUT-309 was a "flexible-robust" adsorbent with multistep adsorption isotherms for C3H4 rather than C3H6 at a wide temperature range. The guest-dependent pore-opening behavior endows BUT-309 with high potential in the C3H4/C3H6 separation. The C3H4 adsorption measurements of BUT-309 at 273-323 K showed that the lowering of the temperature induced the pore-opening action at lower pressure. Column breakthrough experiments further confirmed the capability of BUT-309 for the efficient removal of C3H4 from a C3H4/C3H6 binary gas, and the C3H6 processing capacity at 273 K (15.7 cm3 g-1) was higher than that at 298 K (35.2 cm3 g-1). This work shows a rare example of "flexible-robust" MOFs and demonstrated its high potential for C3H4/C3H6 separation.

2.
Dig Dis Sci ; 68(6): 2276-2284, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-36725765

RESUMEN

BACKGROUND: Per Oral Endoscopic Myotomy (POEM) is a minimally invasive treatment for achalasia with results comparable to laparoscopic Heller myotomy (LHM). Studies have described the development of proficiency for endoscopists learning to perform POEM, and societies have defined educational and technical objectives for advanced endoscopy fellows in training. However, there is limited guidance on the organizational strategy and educational plan necessary to develop an achalasia service with POEM expertise. AIMS: We aim to outline the steps for design and implementation of a successful POEM program. METHODS: We reported our experience developing a multi-disciplinary clinical program for POEM and the steps taken to achieve procedural proficiency. We also reported our technical success (successful tunneling into the gastric cardia and myotomy of LES muscle fibers) and clinical success (post-procedure Eckardt score ≤ 3) at 3-6 months and 12 months post-procedure. Adverse events were classified per the ASGE lexicon for endoscopic adverse events. RESULTS: After creating a multi-disciplinary clinical program for achalasia and completing procedural proficiency for POEM, our technical success rate was 100% and clinical success rate 90% for the first 41 patients. One adverse event (2.4%) occurred, moderate in severity per the American Society of Gastrointestinal Endoscopy (ASGE) lexicon for adverse endoscopic events. CONCLUSION: In this study, we outlined the steps involved to establish a POEM service in a large integrated healthcare system. Prior competency in interventional endoscopy, procedural training models, POEM observation and education, proctorship, and interdisciplinary patient care are recommended.


Asunto(s)
Acalasia del Esófago , Miotomía de Heller , Miotomía , Cirugía Endoscópica por Orificios Naturales , Humanos , Acalasia del Esófago/cirugía , Endoscopía Gastrointestinal , Miotomía/métodos , Resultado del Tratamiento , Cirugía Endoscópica por Orificios Naturales/métodos , Esfínter Esofágico Inferior/cirugía
3.
Chem Biodivers ; 19(6): e202101004, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35514039

RESUMEN

An undescribed C22-quassinoid named sergeolide A (1) and fifteen known quassinoids (2-16) were obtained from the seeds of Brucea javanica (Simaroubaceae). All chemical structures were established based on spectroscopic data and X-ray diffraction analysis. Sergeolide A (1) is the first example of a naturally occurring C22-quassinoid bearing a butenolide group fused the A ring of the bruceolide skeleton from Brucea genus. And this is the first report of the NMR data for desmethyl-bruceines B (2) and C (3) and the crystal structure for bruceolide (11). In addition, all isolates were evaluated for their anti-pancreatic adenocarcinoma activity by measuring the growth inhibitory of the MIA PaCa-2 cell lines. Consequently, compounds 1, 7-10, and 12-16 exhibited potent anti-pancreatic cancer activity in vitro (IC50 =0.054∼0.357 µM).


Asunto(s)
Adenocarcinoma , Brucea , Cuassinas , Adenocarcinoma/tratamiento farmacológico , Brucea/química , Brucea javanica , Humanos , Estructura Molecular , Cuassinas/análisis , Cuassinas/química , Cuassinas/farmacología , Semillas/química
4.
Molecules ; 27(24)2022 Dec 12.
Artículo en Inglés | MEDLINE | ID: mdl-36557941

RESUMEN

A novel macrolactam named oxalactam A (1), three known dipeptides (2-4) as well as other known alkaloids (5-7) were obtained from the endophytic fungus Penicillium oxalicum, which was derived from the tuber of Icacina trichantha (Icacinaceae). All chemical structures were established based on spectroscopic data, chemical methods, ECD calculations, and 13C-DP4+ analysis. Among them, oxalactam A (1) is a 16-membered polyenic macrolactam bearing a new skeleton of 2,9-dimethyl-azacyclohexadecane core and exhibited potent anti-Rhizoctonia solani activity with a MIC value of 10 µg/mL in vitro. The plausible biosynthetic pathway of 1 was also proposed via the alanyl protecting mechanism. Notably, three dipeptides (2-4) were first identified from the endophytic fungus P. oxalicum and the NMR data of cyclo(L-Trp-L-Glu) (2) was reported for the first time. In addition, the binding interactions between compound 1 and the sterol 14α-demethylase enzyme (CYP51) were studied by molecular docking and dynamics technologies, and the results revealed that the 16-membered polyenic macrolactam could be a promising CYP51 inhibitor to develop as a new anti-Rhizoctonia solani fungicide.


Asunto(s)
Fungicidas Industriales , Penicillium , Simulación del Acoplamiento Molecular , Penicillium/química , Fungicidas Industriales/farmacología , Dipéptidos/metabolismo , Estructura Molecular
5.
J Neurosci Res ; 99(5): 1308-1324, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-33634546

RESUMEN

Neurodegenerative diseases (NDs) are incurable and can develop progressively debilitating disorders, including dementia and ataxias. Alzheimer's disease and Parkinson's disease are the most common NDs that mainly affect the elderly people. There is an urgent need to develop new diagnostic tools so that patients can be accurately stratified at an early stage. As a common post-translational modification, protein glycosylation plays a key role in physiological and pathological processes. The abnormal changes in glycosylation are associated with the altered biological pathways in NDs. The pathogenesis-related proteins, like amyloid-ß and microtubule-associated protein tau, have altered glycosylation. Importantly, specific glycosylation changes in cerebrospinal fluid, blood and urine are valuable for revealing neurodegeneration in the early stages. This review describes the emerging biomarkers based on glycoproteomics in NDs, highlighting the potential applications of glycoprotein biomarkers in the early detection of diseases, monitoring of the disease progression, and measurement of the therapeutic responses. The mass spectrometry-based strategies for characterizing glycoprotein biomarkers are also introduced.


Asunto(s)
Glicoproteínas/metabolismo , Enfermedades Neurodegenerativas/diagnóstico , Enfermedades Neurodegenerativas/metabolismo , Neuronas/metabolismo , Proteómica/métodos , Biomarcadores/metabolismo , Glicoproteínas/genética , Humanos , Enfermedades Neurodegenerativas/genética , Pronóstico
6.
Bioorg Chem ; 94: 103389, 2020 01.
Artículo en Inglés | MEDLINE | ID: mdl-31753312

RESUMEN

Numerous post-translational modifications (PTMs) of the Parkinson's disease (PD) associated α-synuclein (α-syn) protein have been recognised to play critical roles in disease aetiology. Indeed, dysregulated phosphorylation and proteolysis are thought to modulate α-syn aggregation and disease progression. Among the PTMs, enzymatic glycosylation with N-acetylglucosamine (GlcNAc) onto the protein's hydroxylated amino acid residues is reported to deliver protective effects against its pathogenic processing. This modification has been reported to alter its pathogenic self-assembly. As such, manipulation of the protein's O-GlcNAcylation status has been proposed to offer a PD therapeutic route. However, targeting upstream cellular processes can lead to mechanism-based toxicity as the enzymes governing O-GlcNAc cycling modify thousands of acceptor substrates. Small glycopeptides that couple the protective effects of O-GlcNAc with the selectivity of recognition sequences may prove useful tools to modulate protein aggregation. Here we discuss efforts to probe the effects of various O-GlcNAc modified peptides on wild-type α-synuclein aggregation.


Asunto(s)
Acetilglucosamina/metabolismo , alfa-Sinucleína/metabolismo , Acetilglucosamina/química , Conformación de Carbohidratos , Relación Dosis-Respuesta a Droga , Glicosilación , Humanos , Enfermedad de Parkinson/metabolismo , Agregado de Proteínas/efectos de los fármacos , Relación Estructura-Actividad , alfa-Sinucleína/química , alfa-Sinucleína/genética
7.
Acta Pharmacol Sin ; 41(4): 483-498, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-31586134

RESUMEN

Abnormal protein aggregation has been linked to many neurodegenerative diseases, including Parkinson's disease (PD). The main pathological hallmark of PD is the formation of Lewy bodies (LBs) and Lewy neurites, both of which contain the presynaptic protein alpha-synuclein (α-syn). Under normal conditions, native α-syn exists in a soluble unfolded state but undergoes misfolding and aggregation into toxic aggregates under pathological conditions. Toxic α-syn species, especially oligomers, can cause oxidative stress, membrane penetration, synaptic and mitochondrial dysfunction, as well as other damage, leading to neuronal death and eventually neurodegeneration. Early diagnosis and treatments targeting PD pathogenesis are urgently needed. Given its critical role in PD, α-syn is an attractive target for the development of both diagnostic tools and effective therapeutics. This review summarizes the progress toward discovering imaging probes and aggregation inhibitors for α-syn. Relevant strategies and techniques in the discovery of α-syn-targeted drugs are also discussed.


Asunto(s)
Flavonoides/farmacología , Colorantes Fluorescentes/farmacología , alfa-Sinucleína/antagonistas & inhibidores , Animales , Flavonoides/química , Colorantes Fluorescentes/química , Humanos , Enfermedades Neurodegenerativas/diagnóstico , Enfermedades Neurodegenerativas/tratamiento farmacológico , Enfermedades Neurodegenerativas/metabolismo , Tomografía de Emisión de Positrones , Agregado de Proteínas/efectos de los fármacos , Tomografía Computarizada de Emisión de Fotón Único , alfa-Sinucleína/metabolismo
8.
J Clin Gastroenterol ; 53(4): 304-308, 2019 04.
Artículo en Inglés | MEDLINE | ID: mdl-29668560

RESUMEN

BACKGROUND AND AIMS: The standard of care for managing pancreaticobiliary disease in altered Roux-en-Y gastric bypass patients is laparoscopy-assisted endoscopic retrograde cholangiopancreatography (LA-ERCP), but is limited by cost and adverse events. Recently a minimally invasive, completely endoscopic approach using endoscopic ultrasound (EUS) directed transgastric ERCP (EDGE) has been described. We aim to compare EDGE to LA-ERCP in this study. METHODS: Patients from May 2005 to June 2017 with Roux-en-Y gastric bypass anatomy having undergone LA-ERCP or EDGE at 4 tertiary centers were captured in a registry. Patient demographics, procedural details, and clinical outcomes were measured for each group. RESULTS: Seventy-two patients (n=29 EDGE, n=43 LA-ERCP) were included in this study. There was no significant difference in the technical success of EDGE gastrogastric fistula (96.5%) versus LA-gastrostomy creation (100%). The success rate of achieving therapeutic ERCP (EDGE 96.5% vs. LA-ERCP 97.7%) and number of ERCP (EDGE 1.2 vs. LA-ERCP 1.02) needed to achieve clinical resolution was similar between both groups. Adverse event rate for EDGE, 24% (7/29) and LA-ERCP, 19% (8/43) was similar. The total procedure time (73 vs. 184 min) and length of hospital stay (0.8 vs. 2.65 d) was significantly shorter for EDGE compared to LA-ERCP. The overall weight change after EDGE was -6.6 lbs at an average 28-week follow-up. CONCLUSIONS: This study suggests that the EDGE procedure has similar technical success and adverse events compared with LA-ERCP with the benefit of significantly shorter procedure times and hospital stay. EDGE may offer a minimally invasive, effective option, with less resource utilization, and without significant weight gain.


Asunto(s)
Colangiopancreatografia Retrógrada Endoscópica/métodos , Derivación Gástrica/métodos , Laparoscopía/métodos , Enfermedades Pancreáticas/cirugía , Adulto , Anciano , Anciano de 80 o más Años , Enfermedades de las Vías Biliares/cirugía , Colangiopancreatografia Retrógrada Endoscópica/efectos adversos , Endosonografía/métodos , Femenino , Estudios de Seguimiento , Humanos , Tiempo de Internación , Masculino , Persona de Mediana Edad , Sistema de Registros , Estudios Retrospectivos , Centros de Atención Terciaria , Factores de Tiempo
9.
J Clin Gastroenterol ; 53(1): 71-75, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-29517713

RESUMEN

INTRODUCTION: In patients with pancreaticobiliary lesions anticipating surgical resection, digital pancreaticocholangioscopy can be used to identify the extent of disease. This presurgical"mapping" could change the surgical plan and optimize patient care. MATERIALS AND METHODS: Patients with pancreaticobiliary lesions anticipating surgery who underwent endoscopic retrograde cholangiopancreatography with digital pancreaticocholangioscopy from 9 international centers were included. Primary outcome was whether pancreaticocholangioscopy altered the surgical plan. Secondary outcome was correlation between surgical and endoscopic histology and adverse events. RESULTS: A total of 118 patients were included (64% male, mean age 69 y): cholangioscopy in 105 patients (89%), pancreatoscopy in 13 patients (11%). Pancreaticocholangioscopy changed the surgical plan in 39 (34%) of patients: 8 of 13 in the pancreatic duct, 32 of 105 in the bile duct. In the bile duct, 6 patients (5%) had less extensive surgery, 26 patients (25%) avoided surgery. In the pancreatic duct, 4 patients (31%) had more extensive surgery and 4 patients (31%) had less extensive surgery. Four patients with downstaged surgery had positive margins on surgical resection; 1 required additional surgical intervention. Overall correlation between endoscopy and surgical histology was 88%. Adverse events included post endoscopic retrograde cholangiopancreatography pancreatitis in 3 patients (2.5%). CONCLUSION: Digital pancreaticocholangioscopy can be effectively used as a mapping tool to delineate the degree of involvement of biliary lesions before surgical resection, in some cases altering the surgical plan. Prospective studies are needed, especially when downstaging surgery.


Asunto(s)
Neoplasias del Sistema Biliar/cirugía , Procedimientos Quirúrgicos del Sistema Biliar/métodos , Colangiopancreatografia Retrógrada Endoscópica/métodos , Neoplasias Pancreáticas/cirugía , Anciano , Anciano de 80 o más Años , Neoplasias del Sistema Biliar/patología , Colangiopancreatografia Retrógrada Endoscópica/efectos adversos , Endoscopía del Sistema Digestivo/métodos , Femenino , Humanos , Masculino , Márgenes de Escisión , Persona de Mediana Edad , Neoplasias Pancreáticas/patología , Estudios Retrospectivos
10.
J Clin Gastroenterol ; 53(8): e352-e355, 2019 09.
Artículo en Inglés | MEDLINE | ID: mdl-30702485

RESUMEN

BACKGROUND: Per-oral endoscopic myotomy (POEM) has become the preferred alternative treatment to standard Heller myotomy for patients with esophageal achalasia, in Latin American countries. The aim of our study was to evaluate the efficacy and safety of a POEM in the management of achalasia with and without Chagas disease in patients receiving POEM. METHODS: Patients who underwent POEM from tertiary centers in Latin America were included in a dedicated registry. Countries included Brazil, Colombia, Ecuador, Mexico, Nicaragua, and Venezuela. Patients enrolled needed to have a preoperative manometry and swallow contrast study confirming achalasia. Clinical success was defined as significant improvement in Eckardt score after therapy. RESULTS: POEM was technically successful in 81/89 (91%) patients (mean age, 44 y). There was a significant decrease in preprocedure and postprocedure Eckardt score from 8.7 (range, 3 to 12) to 2.15 (0 to 10) (P<0.001), preprocedure and postprocedure barium swallow evaluation (98% vs. 89%; P=0.017), and preprocedure and postprocedure lower esophageal sphincter pressure measurement (from 35 to 13.8 mm Hg; P<0.001). Clinical success was achieved in 93% of patients. Patients with Chagas disease (n=58) were 9.5 times more likely to respond to POEM (P=0.0020; odds ratio, 9.5). CONCLUSIONS: POEM is an efficacious and safe therapeutic modality for treatment of achalasia in Latin America. Chagas disease-related achalasia seems to particularly respond better to POEM when it is performed by experienced endoscopists.


Asunto(s)
Acalasia del Esófago/epidemiología , Cirugía Endoscópica por Orificios Naturales/estadística & datos numéricos , Adolescente , Adulto , Anciano , Niño , Preescolar , Estudios de Cohortes , Acalasia del Esófago/cirugía , Esfínter Esofágico Inferior/cirugía , Femenino , Humanos , Lactante , América Latina/epidemiología , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Adulto Joven
11.
Endoscopy ; 50(11): 1053-1058, 2018 11.
Artículo en Inglés | MEDLINE | ID: mdl-29649841

RESUMEN

BACKGROUND: Gastroparesis is a difficult-to-treat motility disorder with a poor response to medical therapy. Gastric peroral endoscopic pyloromyotomy (G-POEM) has been offered as a novel therapy in the treatment of refractory gastroparesis. We present a multicenter case series of our experience with G-POEM. METHODS: This is an international multicenter case series of patients who underwent G-POEM for the treatment of gastroparesis. The severity of gastroparesis was assessed by delayed gastric emptying scintigraphy (GES) and an elevated gastroparesis cardinal symptoms index (GCSI). Patients then underwent G-POEM using the submucosal tunneling technique. The primary endpoint was improvement in the GCSI score and improvement in gastric emptying on repeat scintigraphy. Secondary endpoints were technical success, complication rate, procedure duration, and length of hospital stay post-procedure. RESULTS: G-POEM was technically successful in all 33 patients. Symptomatic improvement was seen in 28/33 patients (85 %), with a decrease in symptom score by GCSI from 3.3 to 0.8 at follow-up (P < 0.001). The mean procedure duration was 77.6 minutes (37 - 255 minutes). Mean GES improved significantly from 222.4 minutes to 143.16 minutes (P < 0.001). Complications were minimal and included bleeding (n = 1) and an ulcer (n = 1) treated conservatively. The mean length of hospital stay post-procedure was 5.4 days (1 - 14 days). The mean follow-up duration was 11.5 months (2 - 31 months). CONCLUSION: G-POEM is a technically feasible, safe, and successful procedure for the treatment of refractory gastroparesis. A further multicenter comparative study should be performed to compare this technique to laparoscopic pyloromyotomy.


Asunto(s)
Gastroparesia/cirugía , Piloromiotomia/métodos , Adulto , Anciano , Anciano de 80 o más Años , Endoscopía Gastrointestinal , Femenino , Francia , Vaciamiento Gástrico , Gastroparesia/diagnóstico por imagen , Gastroparesia/fisiopatología , Humanos , Tiempo de Internación , Masculino , Persona de Mediana Edad , Tempo Operativo , Piloromiotomia/efectos adversos , Cintigrafía , Índice de Severidad de la Enfermedad , Evaluación de Síntomas , Resultado del Tratamiento , Estados Unidos , Adulto Joven
12.
Inorg Chem ; 57(22): 14260-14268, 2018 Nov 19.
Artículo en Inglés | MEDLINE | ID: mdl-30403482

RESUMEN

As the Cr2O72- anion is highly toxic, new sensors have been developing for its effective detection from water, among which metal-organic frameworks (MOFs) show distinct superiority over many other materials. Herein, a new fluorescent Zr(IV)-based MOF, [Zr6O4(OH)8(H2O)4(sbtc)2] (referred to as BUT-28), based on the di-isophthalate ligand with a central CH═CH moiety, trans-stilbene-3,3',5,5'-tetracarboxylate (sbtc4-), has been prepared and structurally determined. The MOF shows excellent stability in neutral, highly acidic, and weakly basic aqueous solutions. Moreover, no essential uptake loss in three cycles of water vapor adsorption-desorption measurements was observed for BUT-28, suggesting the robustness of the porous framework and its great potential for long-term use. Fluorescent measurements were carried out for BUT-28 and an isostructural MOF, Zr-abtc, which is constructed from the di-isophthalate ligand with a central N═N moiety, azobenzene-3,3',5,5'-tetracarboxylate (abtc4-). Interestingly, Zr-abtc shows very weak fluorescent emission. In contrast, BUT-28 exhibits relatively strong fluorescence and serves as a promising sensory material for the detection of trace Cr2O72- (limit of detection: 36 ppb) in aqueous solutions by selective and sensitive fluorescence quenching effect.

13.
Acta Pharmacol Sin ; 37(6): 719-30, 2016 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-26997567

RESUMEN

With accumulating evidence suggesting that amyloid-ß (Aß) deposition is a good diagnostic biomarker for Alzheimer's disease (AD), the discovery of active Aß probes has become an active area of research. Among the existing imaging methods, optical imaging targeting Aß aggregates (fibrils or oligomers), especially using near-infrared (NIR) fluorescent probes, is increasingly recognized as a promising approach for the early diagnosis of AD due to its real time detection, low cost, lack of radioactive exposure and high-resolution. In the past decade, a variety of fluorescent probes have been developed and tested for efficiency in vitro, and several probes have shown efficacy in AD transgenic mice. This review classifies these representative probes based on their chemical structures and functional modes (dominant solvent-dependent mode and a novel solvent-independent mode). Moreover, the pharmaceutical characteristics of these representative probes are summarized and discussed. This review provides important perspectives for the future development of novel NIR Aß diagnostic probes.


Asunto(s)
Enfermedad de Alzheimer/diagnóstico por imagen , Péptidos beta-Amiloides/análisis , Colorantes Fluorescentes/química , Imagen Óptica/métodos , Enfermedad de Alzheimer/patología , Animales , Benzotiazoles , Compuestos de Boro/química , Curcumina/química , Humanos , Estilbenos/química , Tiazoles/química , Tiofenos/química
14.
Beijing Da Xue Xue Bao Yi Xue Ban ; 48(1): 1-4, 2016 Feb 18.
Artículo en Zh | MEDLINE | ID: mdl-26885900

RESUMEN

The human embryonic stem cells (hESCs) serve as a self-renewable, genetically-healthy, pluripotent and single source of all body cells, tissues and organs. Therefore, it is considered as the good standard for all human stem cells by US, Europe and international authorities. In this study, the standard and healthy human mesenchymal progenitors, ligament tissues, cardiomyocytes, keratinocytes, primary neurons, fibroblasts, and salivary serous cells were differentiated from hESCs. The human cellular health-safety of NaF, retinoic acid, 5-fluorouracil, dexamethasone, penicillin G, adriamycin, lead acetate PbAc, bisphenol A-biglycidyl methacrylate (Bis-GMA) were evaluated selectively on the standardized platforms of hESCs, hESCs-derived cardiomyocytes, keratinocytes, primary neurons, and fibroblasts. The evaluations were compared with those on the currently most adopted cellular platforms. Particularly, the sensitivity difference of PM2.5 toxicity on standardized and healthy hESCs derived fibroblasts, currently adopted immortalized human bronchial epithelial cells Beas-2B and human umbilical vein endothelial cells (HUVECs) were evaluated. The RESULTS showed that the standardized hESCs cellular platforms provided more sensitivity and accuracy for human cellular health-safety evaluation.


Asunto(s)
Células Madre Embrionarias Humanas/citología , Pruebas de Toxicidad , Diferenciación Celular , Fibroblastos/citología , Células Madre Embrionarias Humanas/efectos de los fármacos , Humanos , Queratinocitos/citología , Miocitos Cardíacos/citología , Neuronas/citología
15.
Beijing Da Xue Xue Bao Yi Xue Ban ; 47(1): 62-6, 2015 Feb 18.
Artículo en Zh | MEDLINE | ID: mdl-25686331

RESUMEN

OBJECTIVE: To explore the reinforcement of polyglycidyl methacrylate (PGMA) pre-impregnated quartz fiber mesh in denture base materials by investigation of interface compatibility and fracture resistance. METHODS: 1-layer, 2-layer, 3-layer PGMA pre-impregnated quartz fiber meshes, electrolyzed cobalt-chromium alloy mesh and cobalt-chromium alloy mesh conditioned by metal primer were integrated in polymethyl methacrylate (PMMA) resin by sandwich embedding method. Block samples of 5 groups were prepared (40 mm×15 mm×2 mm). Fracture resistance was determined in a 3-point bending test at 2 mm/min. Scanning electron microscope (SEM), micrographs were taken from the fractured surfaces to analyze the bonding interface compatibility. RESULTS: The group of 3-layer PGMA pre-impregnated quartz fiber mesh presented the highest elastic modulus of 6 406 MPa and flexural strength of 227 MPa among the five groups, while the 1-layer and 2-layer expressed the similar elastic modulus and flexural strength to the pure PMMA group. The metal groups demonstrated better mechanical properties, while the metal surface conditioner played much better. The metal surface conditioner pre-impregnated cobalt-chromium alloy and PGMA pre-impregnated quartz fiber mesh showed compatible interface with PMMA. CONCLUSION: The mechanical properties were improved by the increasing of the fiber by adding the more meshed. Although the benign interface did help the compatibility, the quantity of the fibers played an important role in the strength.


Asunto(s)
Bases para Dentadura , Ácidos Polimetacrílicos , Polimetil Metacrilato , Resinas Acrílicas , Aleaciones de Cromo , Ensayo de Materiales , Metacrilatos , Docilidad , Cuarzo
20.
Zhong Yao Cai ; 36(12): 1926-9, 2013 Dec.
Artículo en Zh | MEDLINE | ID: mdl-25090672

RESUMEN

OBJECTIVE: To analyze the essential oil from the rhizome of Curcuma aromatica of different growth periods, and to provide the scientific reference for reasonable cultivation and quality control of this plant. METHODS: The essential oil was extracted by hydrodistillation and analyzed with GC-MS. The relative contents were determined with area normalization method. RESULTS: The main volatile constituents in the rhizome of Curcuma aromatica were basically the same. Among these volatile constituents, curdione was the major. The relative content of curdione was 16.35% in the rhizome of wild plant in Hengxian county, and 15.81% in the rhizome of one-year-old plant in Mingyang farm, Nanning city. The relative content of eucalyptol in the 2-year-old cultivated rhizome in Hengxian county was 15.40%, and 14.59% in the rhizome of wild plant in Hengxian county. beta-Elemene, beta-caryophyllene,eugenol and germacrone were also the main constituents in the rhizome essential oil. CONCLUSION: Volatile constituents in the rhizome of Curcuma aromatica are similar to each other,but the relative content of each component is different. This result can provide the scientific foundation for the cultivation of Curcuma aromatica.


Asunto(s)
Curcuma/química , Aceites Volátiles/análisis , Aceites de Plantas/análisis , Rizoma/química , Sesquiterpenos de Germacrano/análisis , Curcuma/crecimiento & desarrollo , Ciclohexanoles/análisis , Eucaliptol , Cromatografía de Gases y Espectrometría de Masas , Monoterpenos/análisis , Aceites Volátiles/química , Aceites Volátiles/aislamiento & purificación , Aceites de Plantas/química , Aceites de Plantas/aislamiento & purificación , Control de Calidad , Rizoma/crecimiento & desarrollo , Sesquiterpenos/análisis , Factores de Tiempo
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