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1.
Opt Express ; 30(21): 38208-38215, 2022 Oct 10.
Artículo en Inglés | MEDLINE | ID: mdl-36258387

RESUMEN

High-performance infrared p-i-n photodetectors based on InAs/InAsSb/AlAsSb superlattices on GaSb substrate have been demonstrated at 300K. These photodetectors exhibit 50% and 100% cut-off wavelength of ∼3.2 µm and ∼3.5 µm, respectively. Under -130 mV bias voltage, the device exhibits a peak responsivity of 0.56 A/W, corresponding to a quantum efficiency (QE) of 28%. The dark current density at 0 mV and -130 mV bias voltage are 8.17 × 10-2 A/cm2 and 5.02 × 10-1 A/cm2, respectively. The device exhibits a saturated dark current shot noise limited specific detectivity (D*) of 3.43 × 109 cm·Hz1/2/W (at a peak responsivity of 2.5 µm) under -130 mV of applied bias.

2.
BMC Ophthalmol ; 22(1): 95, 2022 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-35227222

RESUMEN

BACKGROUND: To investigate the level of knowledge, attitude, and practices about glaucoma and associated factors among primary glaucoma patients in Kunming, China. METHODS: A hospital-based study was conducted on 93 patients from the First Affiliated Hospital of Kunming Medical University. Interviewer-administered questionnaires were used to collect data after written informed consent. Data were analyzed by SPSS 19.0. Univariate and multivariate logistic regression models were used to identify factors. A Chi-square test was used to analyze the association between knowledge of glaucoma and medication compliance, Mann-Whitney U test was performed to assess the relationship between knowledge of glaucoma and quality of life in patients with glaucoma. P-value < 0.05 was considered statistically significant. RESULTS: Among 93 patients, 55 (59.14%) were aware of glaucoma, 48 (51.61%) had good knowledge of glaucoma, while 45 (48.39%) had poor knowledge. Younger age and duration of glaucoma were associated positively with knowledge of glaucoma. 87 (93.54%) patients got knowledge of their disease from doctors. 79.17% of respondents could use all the anti-glaucoma medications on time, out of which 54.17% had good knowledge of glaucoma while 25.00% had poor knowledge of glaucoma. 30.56% of respondents used to stop anti-glaucoma medications on their own out of which only 9.72% had good knowledge of glaucoma while 20.83% had poor knowledge of glaucoma. Patients with good knowledge of glaucoma had lower scores on the Glaucoma Quality of Life-15 questionnaire. Thus, the compliance to anti-glaucoma medications and glaucoma-related quality of life were better in patients with good knowledge. CONCLUSIONS: The level of knowledge of glaucoma among patients in Kunming is relatively low. Improving knowledge with suitable content for patients through effective multiple means such as the mass media rather than relying only on ophthalmologists may be a veritable first step in combating blindness from glaucoma and enhancing patients' quality of life.


Asunto(s)
Glaucoma , Calidad de Vida , Glaucoma/tratamiento farmacológico , Conocimientos, Actitudes y Práctica en Salud , Humanos , Cumplimiento de la Medicación , Encuestas y Cuestionarios
3.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 53(3): 517-522, 2022 May.
Artículo en Zh | MEDLINE | ID: mdl-35642164

RESUMEN

Bone remodeling, which is well orchestrated by osteogenesis of osteoblasts and osteoclastogenesis of osteoclasts, maintains the homeostasis of osteal development and metabolism under physiological conditions. Bone morphogenetic protein receptor type 1A, also known as activin receptor-like kinase 3 (ALK3), which exists on cytomembrane, is one of the key receptors of BMP factors, and is an important "gateway" that regulates the entrance of BMP signaling into cells in order to perform biological functions. The roles of BMP signaling in bone remodeling have been extensively studied. Many new discoveries have been reported in recent years through research based on transgenic mice models and focused on ALK3 as targets, shedding new light on the regulations of bone remodeling, cartilage and joint development, and the occurrence and treatment of bone-related diseases. Established understanding has been expanded, but new challenges on existing clinical application of BMPs also appeared. Hence, we reviewed recent studies on ALK3's involvement in bone formation and bone resorption, analyzed its mechanism of action in bone regulation, summarized the roles of ALK3 in the development of cartilage and temporomandibular joint, and reported the latest progress in treatment in preclinical studies, intending to provide references for subsequent studies and clinical applications in the future.


Asunto(s)
Proteínas Morfogenéticas Óseas , Huesos , Animales , Huesos/metabolismo , Homeostasis , Ratones , Osteoclastos/metabolismo , Osteogénesis
4.
Opt Express ; 29(9): 13829-13838, 2021 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-33985111

RESUMEN

The anomalous circular photogalvanic effect (ACPGE) is observed in p-GaAs with a thickness of 2 µm at room temperature, in which circularly polarized light is used to inject spin-polarized carriers and the spin diffusion can generate a macroscopic detectable charge current due to the inverse spin Hall effect. The normalized ACPGE signals show first increasing and then decreasing with increasing the doping concentration. The role of the doping impurities is discussed by both extrinsic and intrinsic models, and both can well explain the variation of ACPGE with the doping concentration.

5.
J Org Chem ; 86(24): 18056-18066, 2021 Dec 17.
Artículo en Inglés | MEDLINE | ID: mdl-34842425

RESUMEN

We report here a direct allenylation reaction of inactive cyclic ethers. The reaction proceeds through a copper-catalyzed 1,4-difunctionalization of 1,3-enynes, with cyano group installed at the allenes simultaneously. This methodology shows a broad functional group compatibility to 1,3-enynes. Diversified allene-modified cyclic ether derivatives were synthesized with high regioselectivity under mild conditions.

6.
J Nat Prod ; 82(5): 1155-1164, 2019 05 24.
Artículo en Inglés | MEDLINE | ID: mdl-30990038

RESUMEN

Two new meroterpenoids, penicianstinoids A and B (1 and 2), and eight new isocoumarins, peniciisocoumarins A-H (3-10), together with 10 known analogues (11-20) were obtained from the mangrove-derived fungus Penicillium sp. TGM112. The structures and absolute configurations of 1-10 were determined by interpretation of detailed NMR, MS spectroscopic data, X-ray diffraction analyses, modified Mosher's method, and calculated electronic circular dichroism data. Compounds 1-4, 7, 8, 10, 12, 13, and 16 showed growth inhibition activity against newly hatched larvae of Helicoverpa armigera Hubner with IC50 values ranging from 50 to 200 µg/mL, respectively. Compounds 1, 2, and 11-15 displayed activity against Caenorhabditis elegans with EC50 values ranging from 9.4 (± 1.0) to 38.2 (± 0.6) µg/mL, respectively. Compound 1 represents an austinoid-like meroterpenoid that is reported here for the second time, in which a carbon-carbon double bond was oxidized to a carbonyl group at C-1'-C-2'.


Asunto(s)
Isocumarinas/aislamiento & purificación , Penicillium/química , Rhizophoraceae/microbiología , Terpenos/aislamiento & purificación , Línea Celular Tumoral , Humanos , Isocumarinas/química , Isocumarinas/farmacología , Espectroscopía de Resonancia Magnética , Terpenos/química , Terpenos/farmacología
7.
J Nat Prod ; 82(1): 27-34, 2019 01 25.
Artículo en Inglés | MEDLINE | ID: mdl-30596489

RESUMEN

Ten new clerodane diterpenoids, polylauioids A-J (1-10), and five known analogues (11-15) were isolated from the roots of Polyalthia laui. Among the new compounds, 3 and 8 are artifacts. The structures were elucidated using spectroscopic methods and by comparison with published NMR spectroscopic data. The absolute configurations of 4, 5, and 7 were defined based on single-crystal X-ray diffraction and electronic circular dichroism data. Compounds 1 and 2 represent the first examples of rearranged 3,4- seco-norclerodane diterpenoids, and a putative biosynthesis pathway for these compounds is proposed. Compounds 1, 4, 6, 7, 9, and 10 showed anti-HIV activities with EC50 values ranging from 12.2 to 35.2 µM.


Asunto(s)
Diterpenos/química , Polyalthia/química , Fármacos Anti-VIH/farmacología , Diterpenos/metabolismo , Diterpenos/farmacología , Espectroscopía de Resonancia Magnética , Estructura Molecular , Raíces de Plantas/química
8.
J Clin Lab Anal ; 33(1): e22638, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30098064

RESUMEN

BACKGROUNDS: The influenza virus is one of the major pathogens that seriously affect human health. It can cause a strong immune response and trigger a series of complications. Interleukin 37 (IL-37) is a newly discovered cytokine that plays an important regulatory role in infection and immunity. To date, there have been few studies on the correlation between influenza virus infection and IL-37. METHODS: Serum levels of IL-37 in 115 patients with influenza A virus (IAV) infection and 102 healthy subjects were measured by an enzyme-linked immunosorbent assay (ELISA). Real-time quantitative PCR (RT-qPCR) was used to detect differences in IL-37 expression in peripheral blood mononuclear cells (PBMCs) between IAV patients and healthy subjects. IL-37 expression was measured in A549 cells and PBMCs infected with IAV H3N2 using ELISA and RT-qPCR. After the H3N2-infected A549 cells were treated with human IL-37, the concentration of viral RNA was determined using RT-qPCR, and the titer of influenza virus was determined by a hemagglutination test. RESULTS: The IL-37 levels in the sera and PBMCs of patients infected with IAV were higher than those of healthy subjects. The expression of IL-37 mRNA and protein in IAV-infected A549 cells and PBMCs was upregulated, and IL-37 protein was able to inhibit the replication of IAV RNA. CONCLUSION: IAV-induced IL-37 expression inhibits IAV replication.


Asunto(s)
Interacciones Huésped-Patógeno/inmunología , Virus de la Influenza A , Gripe Humana , Interleucina-1 , Replicación Viral/inmunología , Células A549 , Adolescente , Adulto , Estudios de Casos y Controles , Femenino , Humanos , Virus de la Influenza A/inmunología , Gripe Humana/inmunología , Gripe Humana/virología , Interleucina-1/sangre , Interleucina-1/inmunología , Leucocitos Mononucleares/inmunología , Leucocitos Mononucleares/virología , Masculino , ARN Viral/sangre , Adulto Joven
9.
J Hum Genet ; 63(5): 639-646, 2018 May.
Artículo en Inglés | MEDLINE | ID: mdl-29531335

RESUMEN

Mutation in the gene encoding microphthalmia-associated transcription factor (MITF) lead to Waardenburg syndrome 2 (WS2), an autosomal dominantly inherited syndrome with auditory-pigmentary abnormalities, which is clinically and genetically heterogeneous. Haploinsufficiency may be the underlying mechanism for WS2. However, the mechanisms explaining the genotypic and phenotypic variations in WS2 caused by MITF mutations are unclear. A previous study revealed that MITF interacts with LEF-1, an important factor in the Wnt signaling pathway, to regulate its own transcription through LEF-1-binding sites on the MITF promoter. In this study, four different WS2-associated MITF mutations (p.R217I, p.R217G, p.R255X, p.R217del) that are associated with highly variable clinical features were chosen. According to the results, LEF-1 can activate the expression of MITF on its own, but MITF proteins inhibited the activation. This inhibition weakens when the dosage of MITF is reduced. Except for p.R217I, p.R255X, p.R217G, and p.R217del lose the ability to activate TYR completely and do not inhibit the LEF-1-mediated activation of the MITF-M promoter, and the haploinsufficiency created by mutant MITF can be overcome; correspondingly, the mutants' associated phenotypes are less severe than that of p.R217I. The dominant negative of p.R217del made it have a second-most severe phenotype. This study's data imply that MITF has a negative feedback loop of regulation to stabilize MITF gene dosage that involves the Wnt signaling pathway and that the interaction of MITF mutants with this pathway drives the genotypic and phenotypic differences observed in Waardenburg syndrome type 2 associated with MITF mutations.


Asunto(s)
Genotipo , Factor de Transcripción Asociado a Microftalmía/genética , Mutación , Fenotipo , Síndrome de Waardenburg/genética , Síndrome de Waardenburg/metabolismo , Vía de Señalización Wnt , Línea Celular , Epistasis Genética , Genes Reporteros , Estudios de Asociación Genética , Humanos , Factor de Unión 1 al Potenciador Linfoide/metabolismo , Modelos Biológicos , Regiones Promotoras Genéticas , Unión Proteica
10.
Org Biomol Chem ; 16(42): 7792-7796, 2018 10 31.
Artículo en Inglés | MEDLINE | ID: mdl-30325392

RESUMEN

A selective Friedel-Crafts acylation of indoles via an unusual cleavage of the amide C-N bond was achieved by triflic anhydride activation. This method offers rapid efficient access to high-biological-value 3-acylindoles, performs a series of scrupulous mechanistic studies and offers a strong courage that amide synthons can form new C-C bonds under transition-metal-free conditions.

11.
J Nat Prod ; 81(4): 1045-1049, 2018 04 27.
Artículo en Inglés | MEDLINE | ID: mdl-29489361

RESUMEN

Three new indole diterpenes, penicilindoles A-C (1-3), were isolated from the mangrove-derived fungus Eupenicillium sp. HJ002. Their planar structures and absolute configurations were determined by interpretation of NMR spectroscopic data, HR-ESIMS, and X-ray diffraction analysis using Cu Kα radiation. The cytotoxic and antibacterial activities were evaluated in vitro; penicilindole A (1) showed cytotoxic activity against human A549 and HepG2 cell lines with IC50 values of 5.5 and 1.5 µM, respectively.


Asunto(s)
Citotoxinas/farmacología , Diterpenos/farmacología , Eupenicillium/química , Rhizophoraceae/microbiología , Células A549 , Antibacterianos/química , Antibacterianos/farmacología , Línea Celular Tumoral , Cristalografía por Rayos X , Citotoxinas/química , Diterpenos/química , Hongos , Células HeLa , Células Hep G2 , Humanos , Indoles/química , Indoles/farmacología , Espectroscopía de Resonancia Magnética/métodos , Penicillium/química
12.
Biochem Biophys Res Commun ; 493(1): 258-262, 2017 11 04.
Artículo en Inglés | MEDLINE | ID: mdl-28893539

RESUMEN

Waardenburg syndrome (WS) is an autosomal dominant inherited non-syndromic type of hereditary hearing loss characterized by varying combinations of sensorineural hearing loss and abnormal pigmentation of the hair, skin, and inner ear. WS is classified into four subtypes (WS1-WS4) based on additional symptoms. WS2 is characterized by the absence of additional symptoms. Recently, we identified a SOX10 missense mutation c.422T > C (p.L141P) associated with WS2. We performed functional assays and found the mutant loses DNA-binding capacity, shows aberrant cytoplasmic and nuclear localization, and fails to interact with PAX3. Therefore, the mutant cannot transactivate the MITF promoter effectively, inhibiting melanin synthesis and leading to WS2. Our study confirmed haploinsufficiency as the underlying pathogenesis for WS2.


Asunto(s)
Haplotipos/genética , Factor de Transcripción PAX3/genética , Polimorfismo de Nucleótido Simple/genética , Factores de Transcripción SOXE/genética , Síndrome de Waardenburg/genética , Adolescente , Humanos , Masculino , Mutación/genética
13.
Opt Express ; 25(3): 1778-1788, 2017 Feb 06.
Artículo en Inglés | MEDLINE | ID: mdl-29519031

RESUMEN

The inhomogeneous broadening of the bi-exciton state in quantum dots, i.e., the inhomogeneous broadening of the upper level of the cascade process, is not only a fundamental problem in quantum dots, but also closely related with the coherent control of this complex system and the quality of the entangled photon pairs, especially the time-bin entangled photon pairs. This inhomogeneous broadening is inherently a two-photon correlated phenomenon. In this work, we construct a genuine Franson-type nonlocal interference process to measure the inhomogeneous broadening of the bi-exciton state. The results show that the inhomogeneous broadening of the bi-exciton state is considerably smaller than that of the exciton state, that is why the entangled photon pairs can be generated by the cascade process in the quantum dot.

14.
Chemistry ; 23(61): 15300-15304, 2017 Nov 02.
Artículo en Inglés | MEDLINE | ID: mdl-28885756

RESUMEN

A concise, novel and flexible metal-free single step to synthesize functionalized quinolines is reported. Triflic anhydride-mediated (Tf2 O) activation of amides is discussed in the presence of pyridine to offer strong electrophiles, thereby showcasing excellent productivity, high regio- and chemoselectivity, and widely tolerable substrates. This approach provides a straightforward and efficient way to construct azaheterocycle structures.

15.
Nanotechnology ; 28(39): 395701, 2017 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-28682302

RESUMEN

We demonstrate the utility of optical second harmonic generation (SHG) polarimetry to perform structural characterization of self-assembled zinc-blende/wurtzite III-V nanowire heterostructures. By analyzing four anisotropic SHG polarimetric patterns, we distinguish between wurtzite (WZ), zinc-blende (ZB) and ZB/WZ mixing III-V semiconducting crystal structures in nanowire systems. By neglecting the surface contributions and treating the bulk crystal within the quasi-static approximation, we can well explain the optical SHG polarimetry from the NWs with diameter from 200-600 nm. We show that the optical in-coupling and out-coupling coefficients arising from depolarization field can determine the polarization of the SHG. We also demonstrate micro-photoluminescence of GaAs quantum dots in related ZB and ZB/WZ mixing sections of core-shell NW structure, in agreement with the SHG polarimetry results. The ability to perform in situ SHG-based crystallographic study of semiconducting single and multi-crystalline nanowire heterostructures will be useful in displaying structure-property relationships of nanodevices.

16.
Ecotoxicology ; 26(9): 1284-1292, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-28900741

RESUMEN

Jingjinji area occupies important position in developing of the Chinese economy, while there exists a sharp conflict between economic growth and limited water resources in this area. To ensure the safety of water consumption of cities in Jingjinji area, we investigated the abundance of three classes of antibiotic resistance genes (ARGs) in water and sediment of six water supply reservoirs in this area. The results showed that the detection frequency of sul1, tetM and ermB were 100%. However, the content ranges of these genes were different (10-5 to 10-2/16S gene copies for sul1, 10-5 to 10-3/16S gene copies for ermB, and 10-5 to 10-3/16S gene copies for tetM). The content of ribosome protection proteins (RPP) genes were the highest in all selected tet genes. The highest abundance of ARGs in water and sediment samples was sampled from Panjiakou reservoir and Guanting reservoir, respectively. Except COD, chla and tetM, there are no significant correlation between water quality parameters and ARGs. Overall, this study provides integrated profiles of the three types of ARGs in water supply reservoirs of Jingjinji area and thus helps to re-evaluate the effects of human activities to water supply reservoirs.


Asunto(s)
Farmacorresistencia Microbiana/genética , Monitoreo del Ambiente , Microbiología del Agua , Abastecimiento de Agua/estadística & datos numéricos , China
17.
Sensors (Basel) ; 17(9)2017 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-28867812

RESUMEN

The measurement of large forces and the presence of errors due to dimensional coupling are significant challenges for multi-dimensional force sensors. To address these challenges, this paper proposes an over-constrained six-dimensional force sensor based on a parallel mechanism of steel ball structures as a measurement module. The steel ball structure can be subject to rolling friction instead of sliding friction, thus reducing the influence of friction. However, because the structure can only withstand unidirectional pressure, the application of steel balls in a six-dimensional force sensor is difficult. Accordingly, a new design of the sensor measurement structure was designed in this study. The static equilibrium and displacement compatibility equations of the sensor prototype's over-constrained structure were established to obtain the transformation function, from which the forces in the measurement branches of the proposed sensor were then analytically derived. The sensor's measurement characteristics were then analysed through numerical examples. Finally, these measurement characteristics were confirmed through calibration and application experiments. The measurement accuracy of the proposed sensor was determined to be 1.28%, with a maximum coupling error of 1.98%, indicating that the proposed sensor successfully overcomes the issues related to steel ball structures and provides sufficient accuracy.

18.
Acta Chim Slov ; 64(3): 633-637, 2017 09.
Artículo en Inglés | MEDLINE | ID: mdl-28862301

RESUMEN

Two CuI complexes based on the π-conjugated tetrathiafulvalene-annulated phenanthroline ligands (TTF-Phen, L1 and L2), [CuI(Xantphos)(L1)]BF4 (1, Xantphos = 9,9-dimethyl-4,5-bis(diphenylphosphino)xanthene) and [CuI(Binap)(L2)]BF4 (2, Binap = 2,2'-bis(diphenylphosphino)-1,1'-binaphthyl), have been synthesized. They have been fully characterized, and their photophysical and electrochemical properties are reported together with those of L1 and L2 for comparison. Both CuI complexes show metal-to-ligand charge transfer (MLCT) absorption bands, whereas the 3MLCT luminescence is strongly quenched.

19.
J Fluoresc ; 26(1): 323-31, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26555291

RESUMEN

A series of new cyclometalated btp-based iridium(III) complexes with three different ancillary ligands, Ir(btp)2(bozp) (3a), Ir(btp)2(btzp) (3b) and Ir(btp)2(izp) (3c) (btp = 2-(benzo[b]thiophen-2-yl)pyridine, bozp =2-(benzo[d]oxazol-2-yl)phenol, btzp =2-(benzo[d]thiazol-2-yl)phenol, izp = 2-(2 H-indazol-2-yl)phenol), have been synthesized and fully characterized. The crystal structure of 3b has been determined by single crystal X-ray diffraction analysis. A comparative study has been carried out for complexes 3a - 3c by UV-vis absorption spectroscopy, photoluminescence spectroscopy, cyclic voltammetry and DFT calculations. This observation illustrates that the substitution of N or S in ancillary ligand can lead to a marked bathochromic shift of absorption and emission wavelengths. The spectroscopic characterisation of these complexes has been complemented by DFT and TD-DFT calculations, supporting the assignment of (3)MLCT/(3)LC to the lowest energy excited state.


Asunto(s)
Iridio/química , Compuestos Organometálicos/química , Piridinas/química , Teoría Cuántica , Tiofenos/química , Cristalografía por Rayos X , Ligandos , Modelos Moleculares , Estructura Molecular , Compuestos Organometálicos/síntesis química
20.
Yao Xue Xue Bao ; 51(12): 1926-33, 2016 12.
Artículo en Zh | MEDLINE | ID: mdl-29923699

RESUMEN

In this study, TRAP molecular markers were used in identification of wild populations and hybrids of Dendrobium officinale, based on the sequences of genes encoding phosphoenolpyruvate carboxylase (PEPC), UDP-glucose pyrophosphorylase (UGP) and phenylalanine ammonia-lyase (PAL). Seven polymorphic target region amplification polymorphism (TRAP) primers were selected from 54 primer combinations and used in the identification of wild populations. Moreover, hybrids had female polymorphic bands, male polymorphic bands and heterozygous bands, which suggest that seven TRAP markers are able to identify the hybrids from their parents. Furthermore, the UPGMA dendrogram revealed that when sample from Guangnan in Yunnan province was used as one parent, reciprocal hybrids grouped with them in first, and then grouped with the other parent. The results indicated that the hybrids were closer to D. officinale from Guangnan population. This study identified the wild populations and hybrids of D. officinale by TRAP molecular markers, which is useful in selection of good varieties for artificial cultivation and early identification of hybrids. The study provides a method in the control of stability of germplasm and quality of D. officinale.


Asunto(s)
ADN de Plantas/genética , Dendrobium/genética , Polimorfismo Genético , China , Marcadores Genéticos
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