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1.
Artigo em Inglês | MEDLINE | ID: mdl-39214390

RESUMO

BACKGROUND AND AIMS: There is significant variability in the immediate post-operative and long-term management of patients undergoing per-oral endoscopic myotomy (POEM), largely stemming from the lack of high-quality evidence. We aimed to establish a consensus on several important questions on the after care of post-POEM patients through a modified Delphi process. METHODS: A steering committee developed an initial questionnaire consisting of 5 domains (33 statements): post-POEM admission/discharge, indication for immediate post-POEM esophagram, peri-procedural medications and diet resumption, clinic follow-up recommendations, and post-POEM reflux surveillance and management. A total of 34 experts participated in the 2 rounds of the Delphi process, with quantitative and qualitative data analyzed for each round to achieve consensus. RESULTS: A total of 23 statements achieved high degree of consensus. Overall, the expert panel agreed on the following: (1) same-day discharge after POEM can be considered in select patients, (2) a single dose of prophylactic antibiotics may be as effective as a short course, (3) a modified diet can be advanced as tolerated, (4) all patients should be followed in clinic and undergo objective testing for surveillance and management of reflux. Consensus could not be achieved on the indication of post-POEM esophagram to evaluate for leak. CONCLUSIONS: The results of this Delphi process established expert agreement on several important issues and provides a practical guidance on key aspects in the care of patients following POEM.

2.
Inorg Chem ; 62(31): 12329-12336, 2023 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-37478416

RESUMO

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.

3.
Dig Dis Sci ; 68(6): 2276-2284, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36725765

RESUMO

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.


Assuntos
Acalasia Esofágica , Miotomia de Heller , Miotomia , Cirurgia Endoscópica por Orifício Natural , Humanos , Acalasia Esofágica/cirurgia , Endoscopia Gastrointestinal , Miotomia/métodos , Resultado do Tratamento , Cirurgia Endoscópica por Orifício Natural/métodos , Esfíncter Esofágico Inferior/cirurgia
4.
Chem Biodivers ; 19(6): e202101004, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35514039

RESUMO

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).


Assuntos
Adenocarcinoma , Brucea , Quassinas , Adenocarcinoma/tratamento farmacológico , Brucea/química , Brucea javanica , Humanos , Estrutura Molecular , Quassinas/análise , Quassinas/química , Quassinas/farmacologia , Sementes/química
5.
Molecules ; 27(24)2022 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-36557941

RESUMO

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.


Assuntos
Fungicidas Industriais , Penicillium , Simulação de Acoplamento Molecular , Penicillium/química , Fungicidas Industriais/farmacologia , Dipeptídeos/metabolismo , Estrutura Molecular
6.
J Neurosci Res ; 99(5): 1308-1324, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33634546

RESUMO

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.


Assuntos
Glicoproteínas/metabolismo , Doenças Neurodegenerativas/diagnóstico , Doenças Neurodegenerativas/metabolismo , Neurônios/metabolismo , Proteômica/métodos , Biomarcadores/metabolismo , Glicoproteínas/genética , Humanos , Doenças Neurodegenerativas/genética , Prognóstico
7.
Bioorg Chem ; 94: 103389, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31753312

RESUMO

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.


Assuntos
Acetilglucosamina/metabolismo , alfa-Sinucleína/metabolismo , Acetilglucosamina/química , Configuração de Carboidratos , Relação Dose-Resposta a Droga , Glicosilação , Humanos , Doença de Parkinson/metabolismo , Agregados Proteicos/efeitos dos fármacos , Relação Estrutura-Atividade , alfa-Sinucleína/química , alfa-Sinucleína/genética
8.
Acta Pharmacol Sin ; 41(4): 483-498, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31586134

RESUMO

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.


Assuntos
Flavonoides/farmacologia , Corantes Fluorescentes/farmacologia , alfa-Sinucleína/antagonistas & inibidores , Animais , Flavonoides/química , Corantes Fluorescentes/química , Humanos , Doenças Neurodegenerativas/diagnóstico , Doenças Neurodegenerativas/tratamento farmacológico , Doenças Neurodegenerativas/metabolismo , Tomografia por Emissão de Pósitrons , Agregados Proteicos/efeitos dos fármacos , Tomografia Computadorizada de Emissão de Fóton Único , alfa-Sinucleína/metabolismo
9.
J Clin Gastroenterol ; 53(4): 304-308, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-29668560

RESUMO

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.


Assuntos
Colangiopancreatografia Retrógrada Endoscópica/métodos , Derivação Gástrica/métodos , Laparoscopia/métodos , Pancreatopatias/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Doenças Biliares/cirurgia , Colangiopancreatografia Retrógrada Endoscópica/efeitos adversos , Endossonografia/métodos , Feminino , Seguimentos , Humanos , Tempo de Internação , Masculino , Pessoa de Meia-Idade , Sistema de Registros , Estudos Retrospectivos , Centros de Atenção Terciária , Fatores de Tempo
10.
J Clin Gastroenterol ; 53(1): 71-75, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-29517713

RESUMO

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.


Assuntos
Neoplasias do Sistema Biliar/cirurgia , Procedimentos Cirúrgicos do Sistema Biliar/métodos , Colangiopancreatografia Retrógrada Endoscópica/métodos , Neoplasias Pancreáticas/cirurgia , Idoso , Idoso de 80 Anos ou mais , Neoplasias do Sistema Biliar/patologia , Colangiopancreatografia Retrógrada Endoscópica/efeitos adversos , Endoscopia do Sistema Digestório/métodos , Feminino , Humanos , Masculino , Margens de Excisão , Pessoa de Meia-Idade , Neoplasias Pancreáticas/patologia , Estudos Retrospectivos
11.
J Clin Gastroenterol ; 53(8): e352-e355, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-30702485

RESUMO

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.


Assuntos
Acalasia Esofágica/epidemiologia , Cirurgia Endoscópica por Orifício Natural/estatística & dados numéricos , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Estudos de Coortes , Acalasia Esofágica/cirurgia , Esfíncter Esofágico Inferior/cirurgia , Feminino , Humanos , Lactente , América Latina/epidemiologia , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Adulto Jovem
12.
Endoscopy ; 50(11): 1053-1058, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-29649841

RESUMO

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.


Assuntos
Gastroparesia/cirurgia , Piloromiotomia/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Endoscopia Gastrointestinal , Feminino , França , Esvaziamento Gástrico , Gastroparesia/diagnóstico por imagem , Gastroparesia/fisiopatologia , Humanos , Tempo de Internação , Masculino , Pessoa de Meia-Idade , Duração da Cirurgia , Piloromiotomia/efeitos adversos , Cintilografia , Índice de Gravidade de Doença , Avaliação de Sintomas , Resultado do Tratamento , Estados Unidos , Adulto Jovem
13.
Inorg Chem ; 57(22): 14260-14268, 2018 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-30403482

RESUMO

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.

14.
Acta Pharmacol Sin ; 37(6): 719-30, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26997567

RESUMO

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.


Assuntos
Doença de Alzheimer/diagnóstico por imagem , Peptídeos beta-Amiloides/análise , Corantes Fluorescentes/química , Imagem Óptica/métodos , Doença de Alzheimer/patologia , Animais , Benzotiazóis , Compostos de Boro/química , Curcumina/química , Humanos , Estilbenos/química , Tiazóis/química , Tiofenos/química
15.
Beijing Da Xue Xue Bao Yi Xue Ban ; 48(1): 1-4, 2016 Feb 18.
Artigo em Chinês | MEDLINE | ID: mdl-26885900

RESUMO

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.


Assuntos
Células-Tronco Embrionárias Humanas/citologia , Testes de Toxicidade , Diferenciação Celular , Fibroblastos/citologia , Células-Tronco Embrionárias Humanas/efeitos dos fármacos , Humanos , Queratinócitos/citologia , Miócitos Cardíacos/citologia , Neurônios/citologia
16.
Beijing Da Xue Xue Bao Yi Xue Ban ; 47(1): 62-6, 2015 Feb 18.
Artigo em Chinês | MEDLINE | ID: mdl-25686331

RESUMO

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.


Assuntos
Bases de Dentadura , Ácidos Polimetacrílicos , Polimetil Metacrilato , Resinas Acrílicas , Ligas de Cromo , Teste de Materiais , Metacrilatos , Maleabilidade , Quartzo
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