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1.
Opt Express ; 28(5): 6027-6035, 2020 Mar 02.
Artículo en Inglés | MEDLINE | ID: mdl-32225860

RESUMEN

AlGaN heterostructure solar-blind avalanche photodiodes (APDs) were fabricated on a double-polished AlN/sapphire template based on a separate absorption and multiplication (SAM) back-illuminated configuration. By employing AlGaN heterostructures with different Al compositions across the entire device, the SAM APD achieved an avalanche gain of over 1×105 at an operated reverse bias of 92 V and a low dark current of 0.5 nA at the onset point of breakdown. These excellent performances were attributed to the acceleration of holes by the polarization electric field with the same direction as the reverse bias and higher impact ionization coefficient of the low-Al-content Al0.2Ga0.8N in the multiplication region. However, the Al0.2Ga0.8N layer produced a photocurrent response in the out of the solar-blind band. To retain the solar-blind detecting characteristic, a periodic Si3N4/SiO2 photonic crystal was deposited on the back of the AlN/sapphire template as an optical filter. This significantly improved the solar-blind characteristic of the device.

2.
Front Pediatr ; 12: 1428513, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39077065

RESUMEN

Background: Acromelic dysplasia caused by FBN1 mutation includes acromicric dysplasia (AD), geleophysic dysplasia 2 (GD2), and Weill-Marchesani syndrome 2 (WMS2). All three diseases share severe short stature and brachydactyly. Besides phenotypic similarity, there is a molecular genetic overlap among them, as identical FBN1 gene mutations have been identified in patients with AD, GD2, and WMS2. However, no family with different acromelic dysplasia phenotypes due to the same variant has been described in English reports. Case report: The proband presented with typical facial features, severe short stature, short limbs, stubby hands and feet and radiological abnormalities. Her elder sister and mother had similar physical features. In addition, her elder sister was found to have aortic valve stenosis by echocardiography. Mutation analysis demonstrated a heterozygous missense mutation, c.5179C>T (p.Arg1727Trp) in exon 42 of the FBN1. The proband and her mother were diagnosed with AD, and her elder sister with GD2. The proband was treated with recombinant human growth hormone (rhGH) and had a body length gain of 0.72 SDS in half a year. Conclusion: These findings expand the phenotypic spectrum of FBN1 gene mutations and highlight that identical FBN1 genotypes can result in different phenotypes of acromelic dysplasia in a family. The efficacy of rhGH therapy in patients with acromelic dysplasia is controversial. More follow-up is needed on the long-term efficacy of rhGH therapy.

3.
Front Pharmacol ; 15: 1288479, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38318135

RESUMEN

Background: This study aimed to assess the overall reporting quality of randomized controlled trials (RCTs) in Chinese herbal medicine (CHM) formulas for patients with diabetes, and to identify factors associated with better reporting quality. Methods: Four databases including PubMed, Embase, Cochrane Library and Web of Science were systematically searched from their inception to December 2022. The reporting quality was assessed based on the Consolidated Standards of Reporting Trials (CONSORT) statement and its CHM formula extension. The overall CONSORT and its CHM formula extension scores were calculated and expressed as proportions separately. We also analyzed the pre-specified study characteristics and performed exploratory regressions to determine their associations with the reporting quality. Results: Seventy-two RCTs were included. Overall reporting quality (mean adherence) were 53.56% and 45.71% on the CONSORT statement and its CHM formula extension, respectively. The strongest associations with reporting quality based on the CONSORT statement were multiple centers and larger author numbers. Compliance with the CHM formula extension, particularly regarding the disclosure of the targeted traditional Chinese medicine (TCM) pattern (s), was generally insufficient. Conclusion: The reporting quality of RCTs in CHM formulas for diabetes remains unsatisfactory, and the adherence to the CHM formula extension is even poorer. In order to ensure transparent and standardized reporting of RCTs, it is essential to advocate for or even mandate adherence of the CONSORT statement and its CHM formula extension when reporting trials in CHM formulas for diabetes by both authors and editors.

4.
Appl Biochem Biotechnol ; 185(2): 541-554, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-29218650

RESUMEN

Exopolysaccharide of Lachnum YM130 (LEP) was purified by diethylaminoethyl cellulose 52 and Sepharose CL-6B column chromatography. LEP-2a was identified to be a homogeneous component with an average molecular weight of 1.31 × 106 Da, which was consisted of mannose and galactose in a molar ratio of 3.8:1.0. The structure of LEP-2a was characterized by methylation analysis, FT-IR analysis, and NMR analysis. Results indicated that LEP-2a was a galactomannan with a backbone, composed of 1,2-linked-α-D-Manp, 1,2,6-linked-α-D-Manp, 1,3,4-linked-α-D-Manp, and 1,3-linked-ß-D-Galp, which was substituted at O-2, O-3, O-4, and O-6 by branches. In vitro antitumor activity assay proved that LEP-2a could significantly enhance the inhibitory effectiveness of 5-FU on Hela cells at the concentrations of 100, 200, 300, and 400 µg/mL. The above results suggested that LEP-2a could be seen as a potential source for developing novel antineoplastic agents.


Asunto(s)
Antineoplásicos , Ascomicetos/química , Polisacáridos Fúngicos , Neoplasias/tratamiento farmacológico , Antineoplásicos/química , Antineoplásicos/aislamiento & purificación , Antineoplásicos/farmacología , Conformación de Carbohidratos , Polisacáridos Fúngicos/química , Polisacáridos Fúngicos/aislamiento & purificación , Polisacáridos Fúngicos/farmacología , Células HeLa , Humanos , Neoplasias/metabolismo , Neoplasias/patología
5.
Int J Biol Macromol ; 86: 10-7, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-26774377

RESUMEN

An extracellular polysaccharide of Lachnum sp. (LEP) was purified by DEAE-cellulose 52 column chromatography and Sepharose CL-6B column chromatography. LEP-2a was identified to be a homogeneous component with an average molecular weight of 3.22 × 10(4)Da. The structure of LEP-2a was characterized by chemical and spectroscopic methods, including methylation analysis, periodate oxidation-smith degradation, infrared spectroscopy and NMR analysis. Results indicated that LEP-2a was a (1→3)-,(1→6)-ß-D-Glcp, whose branch chain was consist of two d-glucopyranosyl residues linked by ß-1,3-glycosidic linkage, which was linked at C6 of the backbone chain by ß-1,6-glycosidic linkage. To study the protective effects of LEP-2a on the ethanol-induced gastric ulcer in mice, LEP-2a (100, 200 and 400mg/kg/d) was given to mice by gavage for 2 weeks. Results showed that LEP-2a significantly decreased the ulcer bleeding areas, pepsin activity, gastric juice volume, gastric juice total acidity and the malondialdehyde (MDA) content in serum. Meanwhile, the superoxide dismutase (SOD) increased significantly. The above findings suggested that LEP-2a had a significant preventive effect against the ethanol-induced gastric ulcer.


Asunto(s)
Antiulcerosos/química , Antiulcerosos/farmacología , Ascomicetos/química , Etanol/efectos adversos , Polisacáridos Fúngicos/química , Polisacáridos Fúngicos/farmacología , Úlcera Gástrica/prevención & control , Animales , Antiulcerosos/aislamiento & purificación , Femenino , Polisacáridos Fúngicos/aislamiento & purificación , Mucosa Gástrica/efectos de los fármacos , Mucosa Gástrica/patología , Glicosilación , Masculino , Metilación , Ratones , Peso Molecular , Monosacáridos/análisis , Úlcera Gástrica/inducido químicamente , Úlcera Gástrica/patología
6.
Carbohydr Polym ; 98(1): 922-30, 2013 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-23987429

RESUMEN

The extracellular polysaccharide (LEP) produced by Lachnum YM281 was obtained from the fermentation broth, and LEP-1b with molecular weight of 4.02×10(4) Da was separated and sequentially purified through DEAE-cellulose 52 column chromatography and Sepharose CL-6B column chromatography. GC-MS, IR and NMR ((1)H, (13)C) spectroscopy analysis indicated that the repeat unit of LEP-1b was: [formula; see text] The effects of LEP-1b on the serum lipids, liver lipids levels and aminotransferase activities of model mice with hyperlipidemic fatty live were studied, and the results showed that LEP-1b had strong lipid lowering and liver protecting effects on mice with hyperlipidemic fatty live.


Asunto(s)
Ascomicetos/química , Citoprotección/efectos de los fármacos , Hipolipemiantes/aislamiento & purificación , Hipolipemiantes/farmacología , Hígado/efectos de los fármacos , Polisacáridos/aislamiento & purificación , Polisacáridos/farmacología , Animales , Ascomicetos/citología , Secuencia de Carbohidratos , Ingestión de Alimentos/efectos de los fármacos , Espacio Extracelular/química , Femenino , Hipolipemiantes/química , Metabolismo de los Lípidos/efectos de los fármacos , Lípidos/sangre , Hígado/citología , Hígado/metabolismo , Ratones , Datos de Secuencia Molecular , Peso Molecular , Polisacáridos/química
7.
Carbohydr Polym ; 97(2): 690-4, 2013 Sep 12.
Artículo en Inglés | MEDLINE | ID: mdl-23911502

RESUMEN

Phosphorylated polysaccharide PLEP-1a, with the PO4³â» content of 6.39%, was prepared from LEP-1a by phosphorylation. IR, (13)C NMR and (31)P NMR results of PLEP-1a showed that the original basic structure of the polysaccharide was not changed, and the -H2PO3 group was linked at C6 of LEP-1a. The results of anti-tumor experiments in vivo showed that 100 mg/kg and 400 mg/kg of LEP-1a could significantly improve the food consumption, body weight, tumor inhibition rate and thymus index of S180 sarcoma mice, and increase the levels of SOD, IL-2 and TNF-α in mice blood serum, indicating that LEP-1a had an excellent anti-tumor activity. Furthermore, PLEP-1a had a significantly enhanced inhibitory effect on S180 sarcoma mice than LEP-1a, suggesting that phosphorylation is an effective way of improving the biological activity of LEP-1a.


Asunto(s)
Antineoplásicos/farmacología , Ascomicetos/química , Polisacáridos/farmacología , Animales , Conducta Alimentaria/efectos de los fármacos , Femenino , Interleucina-2/metabolismo , Espectroscopía de Resonancia Magnética , Masculino , Ratones , Especificidad de Órganos/efectos de los fármacos , Fosfatos/análisis , Fosforilación/efectos de los fármacos , Estándares de Referencia , Sarcoma 180/enzimología , Sarcoma 180/patología , Espectrofotometría Infrarroja , Superóxido Dismutasa/metabolismo , Factor de Necrosis Tumoral alfa/metabolismo , Aumento de Peso/efectos de los fármacos
8.
Food Chem ; 132(1): 338-43, 2012 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-26434299

RESUMEN

A homogeneous extracellular polysaccharide of Lachnum YM261(LEPS-1) with a molecular weight of 21670Da was characterised. According to HPGPC, IR, periodate oxidation and Smith degradation, GC-MS and (1)H NMR analysis, the results indicated that LEPS-1 was a glucan linked by the ß-(1→3)-d-pyran glycosidic bond. The effect of LEPS-1 on anti-ageing in d-gal model mice was also studied. It was found that LEPS-1 significantly increased the activities of antioxidant enzymes (i.e. SOD superoxide dismutase, CAT catalase, GSH-PX glutathione peroxidase) and decreased malondialdehyde (MDA) content in liver, brain and serum of d-gal model mice. These results showed that LEPS-1 had a strong anti-ageing activity.


Asunto(s)
Envejecimiento/efectos de los fármacos , Antioxidantes/química , Polisacáridos/química , Animales , Ratones , Estructura Molecular , Oxidación-Reducción
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