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1.
Anal Chem ; 94(51): 17779-17786, 2022 12 27.
Artigo em Inglês | MEDLINE | ID: mdl-36519823

RESUMO

Self-organization facilitates the formation of specific structures as a result of constituent interactions. In this study, the bottom of a 600 nm hole array photoresist template, which was deposited with a hydrophobic atom transfer radical polymerization (ATRP) initiator, was wetted by treatment with oxygen plasma. After the removal of the photoresist template, ring patterns of the ATRP initiator were formed at the interface between the hydrophobic and wetting regions. Poly[2-(dimethylamino)ethyl methacrylate] (PDMAEMA) was grafted from the ring array of the initiator to immobilize gold nanoparticles (AuNPs) as a uniform ring array on a silicon substrate via repeated swelling/shrinking cycles. The localized surface plasmon resonance (LSPR) peak of the PDMAEMA-AuNP hybrid ring (PAHR) red-shifted after 12 swelling/shrinking cycles. In comparison to gold nanoparticles, scalable gold nanorings can effectively develop a variety of nanostructures to design LSPR-based sensors and optimize the sensing accuracy and stability. To detect epithelial cell adhesion molecules (EpCAM) during the structural change from a ring to a disk, antiEpCAM was anchored onto the PAHR as a biosensor during swelling/shrinking. The coupling of antiEpCAM and EpCAM led to asymptotical convergence from rings to disks as well as blue shifts of the LSPR peaks. Linear correlation between the blue shift and EpCAM concentration showed a limit of detection of ∼27 pg mL-1 and a linear range of 25-200 pg mL-1 for the detection of EpCAM within 30 min. The simple method of combining lithography and plasma technology provides a versatile platform for developing the scalable ring structure of AuNPs for highly sensitive and selective biosensing.


Assuntos
Nanopartículas Metálicas , Ressonância de Plasmônio de Superfície , Ressonância de Plasmônio de Superfície/métodos , Ouro/química , Molécula de Adesão da Célula Epitelial , Nanopartículas Metálicas/química
2.
Dev Dyn ; 243(2): 279-89, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24123365

RESUMO

BACKGROUND: BHLHB5, an OLIG-related basic helix-loop-helix transcription factor, is required for the development of a subset of gamma-amino butyric acid-releasing (GABAergic) amacrine cells and OFF-cone bipolar (CB) cells in mouse retinas. In order to determine BHLHB5's functional mechanism in retinogenesis, we used the Cre-loxP recombination system to genetically trace the lineage of BHLHB5+ cells in normal and Bhlhb5-null retinas. The Bhlhb5-Cre knock-in allele was used to activate the constitutive expression of a GFP reporter in the Bhlhb5-expressing cells, and the cell fates of Bhlhb5-lineage cells were identified by using specific cell markers and were compared between normal and Bhlhb5-null retinas. RESULTS: In addition to GABAergic amacrine and OFF-CB cells, Bhlhb5 lineage cells give rise to ganglion, glycinergic amacrine, rod bipolar, ON-bipolar, and rod photoreceptor cells during normal retinal development. Targeted deletion of Bhlhb5 resulted in the loss of GABAergic amacrine, glycinergic amacrine, dopaminergic amacrine, and Type 2 OFF-CB cells. Furthermore, in the absence of BHLHB5, a portion of Bhlhb5 lineage cells switch their fate and differentiate into cholinergic amacrine cells. CONCLUSIONS: Our data reveal a broad expression pattern of Bhlhb5 throughout retinogenesis and demonstrate the cell-autonomous as well as non-cell-autonomous role of Bhlhb5 in the specification of amacrine and bipolar subtypes.


Assuntos
Células Amácrinas/fisiologia , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Diferenciação Celular/fisiologia , Retina/citologia , Células Bipolares da Retina/fisiologia , Células Amácrinas/metabolismo , Animais , Diferenciação Celular/genética , Proteínas de Fluorescência Verde , Técnicas Histológicas , Imuno-Histoquímica , Camundongos , Retina/crescimento & desenvolvimento , Células Bipolares da Retina/metabolismo
3.
Environ Monit Assess ; 186(8): 4935-46, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24700206

RESUMO

Acid volatile sulfide (AVS) has been regarded as an important factor controlling metal bioavailability in anoxic sediments, but its effect on metal accumulation under natural conditions is poorly understood. Here, a field study of the influence of AVS on metal accumulation by Limnodrilus sp. in a heavily polluted river is provided. Most of the study area was subject to anaerobic and strongly reducing conditions, and the concentration of trace metals in surface sediments was high, as were the concentration of AVS and simultaneously extracted metals (SEM; average AVS = 20.3 µmol g(-1), average ∑SEM5 = 9.42 µmol g(-1); ∑SEM5 refers to the sum of SEMCd, SEMCu, SEMPb, SEMNi, and SEMZn). Only a few species and small quantities of benthic invertebrates were found, and Limnodrilus sp. was dominant. There was no correlation between trace metal accumulation and (SEM-AVS), and in stations where (SEM-AVS) <0, the absolute value of bioaccumulation was high (average ∑BIO5 = 4.07 µmol g(-1); ∑BIO5 refers to the sum of BIOCd, BIOCu, BIOPb, BIONi, and BIOZn), indicating that there was no relationship between (SEM-AVS) and metal accumulation in Limnodrilus sp. This was likely because Limnodrilus sp. ingest sediment particles as their main food source, so pore water metals play a minor role in their bioaccumulation (BIO) of materials. However, ∑BIO5 was significantly correlated with ∑SEM5 (r = 0.795, p < 0.01), revealing that the large number of sulfide-bound metals (SEM) in sediments may play an important role in metal accumulation in Limnodrilus sp., which can assimilate sulfide-associated metals by the help of the digestive fluids in the digestive systems.


Assuntos
Metais Pesados/metabolismo , Oligoquetos/metabolismo , Rios/química , Sulfetos/química , Poluentes Químicos da Água/metabolismo , Animais , Monitoramento Ambiental , Sedimentos Geológicos/química , Invertebrados , Metais Pesados/análise , Metais Pesados/química , Sulfetos/análise , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/química
4.
Talanta ; 256: 124282, 2023 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-36682122

RESUMO

The bottom of a hole-array photoresist template deposited with a hydrophobic atom-transfer radical polymerization (ATRP) initiator was wetted by treatment with oxygen plasma. After the removal of the photoresist template, ring patterns of the ATRP initiator were formed at the interface between the hydrophobic and wetting regions. Polyacrylonitrile (PAN) was grafted from the initiator ring array to covert to polyvinyltetrazole (PVT) rings via a cyano-to-tetrazole reaction, which could adsorb Cu(II) at various concentrations. The Cu(II) ions within the PVT rings were reduced to form a PVT-copper hybrid ring (VCHR), resulting in a blue-shift of the localized surface plasmon resonance (LSPR) peak as the Cu(II) was adsorbed by the PVT rings. The blue-shift and Cu(II) concentration were linearly correlated, with a detection limit of ∼25 pg mL-1 and a linear range of 25-400 pg mL-1 for Cu(II) detection. Although the PVT rings also chelated Pb(II) and Cr(III), these ions did not exhibit obvious LSPR peaks. The VCHR LSPR sensor exhibited excellent selectivity for Cu(II) detection. Combining lithography and plasma technology provides a versatile platform for developing the scalable ring structure of copper for highly sensitive and selective Cu(II) sensing.

5.
Chem Mater ; 35(23): 10228-10237, 2023 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-38107190

RESUMO

The growing interest in the use of near-infrared (NIR) radiation for spectroscopy, optical communication, and medical applications spanning both NIR-I (700-900 nm) and NIR-II (900-1700 nm) has driven the need for new NIR light sources. NIR phosphor-converted light-emitting diodes (pc-LEDs) are expected to replace traditional lamps mainly due to their high efficiency and compact design. Broadband NIR phosphors activated by Cr3+ and Cr4+ have attracted significant research interest, offering emission across a wide range from 700 to 1700 nm. In this work, we synthesized a series of Sc2(1-x)Ga2xO3:Cr3+/4+ materials (x = 0-0.2) with broadband NIR-I (Cr3+) and NIR-II (Cr4+) emission. We observed a substantial increase in the intensity of Cr3+ (approximately 77 times) by incorporating Ga3+ ions. Additionally, our investigation revealed that energy transfer occurred between Cr3+ and Cr4+ ions. Configuration diagrams are presented to elucidate the behavior of Cr3+ and Cr4+ ions within the Sc2O3 matrix. We also observed a phase transition at a pressure of 20.2 GPa, resulting in a new unknown phase where Cr3+ luminescence exhibited a high-symmetry environment. Notably, this study presents the pressure-induced shift of NIR Cr4+ luminescence in Sc2(1-x)Ga2xO3:Cr3+/4+. The linear shifts were estimated at 83 ± 3 and 61 ± 6 cm-1/GPa before and after the phase transition. Overall, our findings shed light on the synthesis, luminescent properties, temperature, and high-pressure behavior within the Sc2(1-x)Ga2xO3:Cr3+/4+ materials. This research contributes to the understanding and potential applications of these materials in the development of efficient NIR light sources and other optical devices.

6.
Int J Ophthalmol ; 8(1): 29-34, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25709903

RESUMO

AIM: To evaluate the effect of amniotic membrane loaded with 5-fluorouracil poly (lactic-co-glycolic acid) (PLGA) nanoparticles (5-FU-NPs) in the surgical outcomes of experimental trabeculectomy in rabbits. METHODS: Thirty-two New Zealand white rabbits were randomly categorized into four groups with 8 rabbits in each group. Group 1, the control group, performed traditional trabeculectomy without adjuvant treatment. While the experimental groups performed compound trabeculectomy with different implantations including amniotic membrane (group 2), 5-FU-NPs (group 3) and amniotic membrane loaded with 5-FU-NPs (group 4). Clinical evaluations including IOP measurement and filtration bleb analysis were performed in all groups postoperatively. RESULTS: There is no significant difference of mean IOP in all groups at first 7d after surgery. While at P14, mean IOPs of experimental group 2 (9.8±2.1 mm Hg), groups 3 (8.9±2.8 mm Hg) and group 4 (7.6±2.3 mm Hg) were significantly reduced compared to control group (12.4±2.6 mm Hg; n=8, P<0.05). At P21, mean IOPs of groups 3 (11.7±3.2 mm Hg) and group 4 (9.9±1.6 mm Hg) were significantly decreased compare to control group (17.9±1.6 mm Hg) and group 2 (16.6±2.8 mm Hg; n=8, P<0.05). At P28, mean IOPs of groups 3 (13.8±3.3 mm Hg) and group 4 (10.6±2.0 mm Hg) were also significantly reduced compare to control group (19.4±2.3 mm Hg) and group 2 (18.5±2.4 mm Hg; n=8, P<0.05). Meanwhile mean IOP of group 4 is significantly decreased compared to group 3 at P28 (n=8, P<0.05). Survival analysis of functional filtration blub in all groups revealed the longest survival time in group 4 (24.9±5.1d) compared to that in group 3 (20.6±4.3d), group 2 (15.0±5.2d) and control group (10.1±5.7d). CONCLUSION: Amniotic membrane loaded with 5-Fu-NPs may function as an effective anti-scarring implant and provides improved long-term surgical outcomes for experimental trabeculectomy in rabbits.

7.
Int J Ophthalmol ; 7(5): 753-8, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25349787

RESUMO

AIM: To make comprehensive molecular diagnosis for retinitis pigmentosa (RP) patients in a consanguineous Han Chinese family using next generation sequencing based Capture-NGS screen technology. METHODS: A five-generation Han Chinese family diagnosed as non-syndromic X-linked recessive RP (XLRP) was recruited, including four affected males, four obligate female carriers and eleven unaffected family members. Capture-NGS was performed using a custom designed capture panel covers 163 known retinal disease genes including 47 RP genes, followed by the validation of detected mutation using Sanger sequencing in all recruited family members. RESULTS: Capture-NGS in one affected 47-year-old male reveals a novel mutation, c.2417_2418insG:p.E806fs, in exon ORF15 of RP GTPase regulator (RPGR) gene results in a frameshift change that results in a premature stop codon and a truncated protein product. The mutation was further validated in three of four affected males and two of four female carriers but not in the other unaffected family members. CONCLUSION: We have identified a novel mutation, c.2417_2418insG:p.E806fs, in a Han Chinese family with XLRP. Our findings expand the mutation spectrum of RPGR and the phenotypic spectrum of XLRP in Han Chinese families, and confirms Capture-NGS could be an effective and economic approach for the comprehensive molecular diagnosis of RP.

8.
PLoS One ; 9(4): e94173, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24736625

RESUMO

PURPOSE: To investigate the role of Pou4f1 and Pou4f2 in the survival of adult retinal ganglion cells (RGCs). METHODS: Conditional alleles of Pou4f1 and Pou4f2 were generated (Pou4f1loxP and Pou4f2loxP respectively) for the removal of Pou4f1 and Pou4f2 in adult retinas. A tamoxifen-inducible Cre was used to delete Pou4f1 and Pou4f2 in adult mice and retinal sections and flat mounts were subjected to immunohistochemistry to confirm the deletion of both alleles and to quantify the changes in the number of RGCs and other retinal neurons. To determine the effect of loss of Pou4f1 and Pou4f2 on RGC survival after axonal injury, controlled optic nerve crush (CONC) was performed and RGC death was assessed. RESULTS: Pou4f1 and Pou4f2 were ablated two weeks after tamoxifen treatment. Retinal interneurons and Müller glial cells are not affected by the ablation of Pou4f1 or Pou4f2 or both. Although the deletion of both Pou4f1 and Pou4f2 slightly delays the death of RGCs at 3 days post-CONC in adult mice, it does not affect the cell death progress afterwards. Moreoever, deletion of Pou4f1 or Pou4f2 or both has no impact on the long-term viability of RGCs at up to 6 months post-tamoxifen treatment. CONCLUSION: Pou4f1 and Pou4f2 are involved in the acute response to damage to RGCs but are dispensable for the long-term survival of adult RGC in mice.


Assuntos
Proteínas de Homeodomínio/genética , Células Ganglionares da Retina/metabolismo , Fator de Transcrição Brn-3A/genética , Fator de Transcrição Brn-3B/genética , Alelos , Animais , Apoptose/genética , Sobrevivência Celular/genética , Deleção de Genes , Técnicas de Inativação de Genes , Ordem dos Genes , Loci Gênicos , Proteínas de Homeodomínio/metabolismo , Interneurônios/efeitos dos fármacos , Interneurônios/metabolismo , Camundongos , Camundongos Knockout , Nervo Óptico/anatomia & histologia , Nervo Óptico/citologia , Fenótipo , Células Ganglionares da Retina/efeitos dos fármacos , Tamoxifeno/farmacologia , Fator de Transcrição Brn-3A/metabolismo , Fator de Transcrição Brn-3B/metabolismo
9.
Mar Pollut Bull ; 84(1-2): 424-36, 2014 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-24880682

RESUMO

Surface sediments from the coastal area of the Leizhou Peninsula in the South China Sea were collected and analyzed and the potential ecological risks in the area were assessed based on acid-volatile sulfide (AVS) model. The AVS levels are between 0.109 and 55.6 µmol g(-1), with the average at 4.45 µmol g(-1). The high AVS-concentration zones include the aquaculture areas of Liusha Bay and the densely populated areas of Zhanjiang Bay. The simultaneously extracted metals (SEM) range from 0.026 µmol g(-1) to 8.61 µmol g(-1), with the average at 0.843 µmol g(-1). Most of high SEM-concentration stations were located in ports or aquaculture zones. Most of the coastal surface sediments of the Leizhou Peninsula (90%) had no adverse biological effects according to the criterion proposed by USEPA (2005); while adverse effects were uncertain in some stations (8%); even in 2 stations (2%) adverse biological effects may be expected.


Assuntos
Monitoramento Ambiental/métodos , Sedimentos Geológicos/química , Poluentes Químicos da Água/química , Ácidos/análise , Aquicultura , Baías , China , Concentração de Íons de Hidrogênio , Metais/análise , Oceanos e Mares , Sulfetos/análise , Compostos Orgânicos Voláteis
10.
Biol Trace Elem Res ; 155(2): 301-13, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23975580

RESUMO

Sediments from 14 stations in the Foshan Waterway, a river crossing the industrial district of Guangdong Province, South China, were sampled and subsequently analyzed. The 14 stations were selected for the pollution discharging features of the river, such as the hydrology, the distribution of pollution sources, and the locations of wastewater outlets. The ecological risks were assessed, and the pollution sources were identified to provide valuable information for environmental impact assessment and pollution control. The spatial variability was high and the range were (in milligrams per kilogram dry weight): Pb, 46.0~382.8; Cu, 33.7~ 482.3; Zn, 62.2~1,568.7; Ni, 28.5~130.7; Cr, 34.7~1,656.1; Cd, 0.50~8.53; Hg, 0.02~8.27; and As, 5.77~66.09. The evaluation results of enrichment factor and potential ecological risk index indicate that the metal pollution in the surface and bottom sediments were severely polluted and could pose serious threat to the ecosystem in most stations. Although the hazard levels of the trace element differed among the stations, Hg was the most serious pollutant in all stations. The results of principal component analysis (PCA) show that the discharge of industrial wastewater is the most important polluting factor whereas domestic sewage, which contains a large amount of organic substances, accelerates metal deposition. And potential pollution sources were identified by the way of integrating the analysis results of PCA and data gained from the local government. Therefore, the conclusion is drawn that Foshan Waterway is seriously polluted with trace elements, both in the surface sediment (0 to 20 cm) and the bottom sediments (21 to 50 cm) are contaminated.


Assuntos
Monitoramento Ambiental , Sedimentos Geológicos/química , Rios/química , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/química , China , Ecologia , Humanos , Medição de Risco
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