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1.
Nat Commun ; 14(1): 7022, 2023 Nov 02.
Artículo en Inglés | MEDLINE | ID: mdl-37919267

RESUMEN

Crystalline porous materials such as covalent organic frameworks (COFs), metal-organic frameworks (MOFs) and porous organic cages (POCs) have been widely applied in various fields with outstanding performances. However, the lack of general and effective methodology for large-scale production limits their further industrial applications. In this work, we developed a general approach comprising high pressure homogenization (HPH), which can realize large-scale synthesis of crystalline porous materials including COFs, MOFs, and POCs under benign conditions. This universal strategy, as illustrated in the proof of principle studies, has prepared 4 COFs, 4 MOFs, and 2 POCs. It can circumvent some drawbacks of existing approaches including low yield, high energy consumption, low efficiency, weak mass/thermal transfer, tedious procedures, poor reproducibility, and high cost. On the basis of this approach, an industrial homogenizer can produce 0.96 ~ 580.48 ton of high-performance COFs, MOFs, and POCs per day, which is unachievable via other methods.

2.
J Am Chem Soc ; 144(15): 6821-6829, 2022 Apr 20.
Artículo en Inglés | MEDLINE | ID: mdl-35380829

RESUMEN

The capture of radioactive I2 vapor from nuclear waste under industrial operating conditions remains a challenging task, as the practical industrial conditions of high temperature (≥150 °C) and low I2 concentration (∼150 ppmv) are unfavorable for I2 adsorption. We report a novel guanidinium-based covalent organic framework (COF), termed TGDM, which can efficiently capture I2 under industrial operating conditions. At 150 °C and 150 ppmv I2, TGDM exhibits an I2 uptake of ∼30 wt %, which is significantly higher than that of the industrial silver-based adsorbents such as Ag@MOR (17 wt %) currently used in the nuclear fuel reprocessing industry. Characterization and theoretical calculations indicate that among the multiple types of adsorption sites in TGDM, only ionic sites can bond to I2 through strong Coulomb interactions under harsh conditions. The abundant ionic groups of TGDM account for its superior I2 capture performance compared to various benchmark adsorbents. In addition, TGDM exhibits exceptionally high chemical and thermal stabilities that fully meet the requirements of practical radioactive I2 capture (high-temperature, humid, and acidic environment) and differentiate it from other ionic COFs. Furthermore, TGDM has excellent recyclability and low cost, which are unavailable for the current industrial silver-based adsorbents. These advantages make TGDM a promising candidate for capturing I2 vapor during nuclear fuel reprocessing. This strategy of incorporating chemically stable ionic guanidine moieties in COF would stimulate the development of new adsorbents for I2 capture and related applications.

3.
Nat Commun ; 13(1): 2132, 2022 04 19.
Artículo en Inglés | MEDLINE | ID: mdl-35440580

RESUMEN

Herein, we report a strategy to construct highly efficient perfluorooctanoic acid (PFOA) adsorbents by installing synergistic electrostatic/hydrophobic sites onto porous organic polymers (POPs). The constructed model material of PAF-1-NDMB (NDMB = N,N-dimethyl-butylamine) demonstrates an exceptionally high PFOA uptake capacity over 2000 mg g-1, which is 14.8 times enhancement compared with its parent material of PAF-1. And it is 32.0 and 24.1 times higher than benchmark materials of DFB-CDP (ß-cyclodextrin (ß-CD)-based polymer network) and activated carbon under the same conditions. Furthermore, PAF-1-NDMB exhibits the highest k2 value of 24,000 g mg-1 h-1 among all reported PFOA sorbents. And it can remove 99.99% PFOA from 1000 ppb to <70 ppt within 2 min, which is lower than the advisory level of Environmental Protection Agency of United States. This work thus not only provides a generic approach for constructing PFOA adsorbents, but also develops POPs as a platform for PFOA capture.


Asunto(s)
Fluorocarburos , Polímeros , Sitios de Unión , Caprilatos , Fluorocarburos/química , Porosidad
4.
Aerosp Med Hum Perform ; 92(2): 92-98, 2021 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-33468289

RESUMEN

BACKGROUND: The effects of seasickness on working performance during motion exposure have been reported, while the aftereffects on working ability and life quality decline (WLD) still remain unclarified.METHODS: Two cohorts of healthy male Chinese subjects received either a single (SSV) or repeated (RSV) sea voyage training program on different vessels. A seasickness incidence (SSI) questionnaire was administered to assess the prevalence of seasickness symptoms (vomiting, nausea, other, or no symptoms). A WLD questionnaire was used to survey the general feeling of WLD (severe, moderate, slight, and none) by a 4-point score as well as the incidence rate (IR) of specific WLD items within 24 h after landing.RESULTS: The RSV cohort had lower overall IR of WLD than the SSV cohort (54.64% vs. 63.78%, N 657 for both cohorts). The landing ship trainees in both cohorts showed higher general WLD score and higher IRs of physical fatigue, sleep disorder, and spontaneous locomotion decrement than those trained on the small vessels. Subjects with vomiting or nausea had higher general WLD score and higher IRs of concentration distraction, physical fatigue, anorexia, and spontaneous locomotion decrement than those with no symptoms. Higher IRs of firing accuracy decline (SSV: 21.35% vs. 7.13%, 9.14%; RSV: 22.11% vs. 9.28%, 5.27%), equipment operation disturbance (SSV: 16.85% vs. 3.57%, 6.85%; RSV: 20.47% vs. 7.85%, 7.03%) were also observed in the vomiting subjects than those with other symptoms and no symptoms.DISCUSSION: Significant WLD after landing was associated with transportation types, seasickness severity, and habituation during sea voyage training.Qi R-R, Xiao S-F, Su Y, Mao Y-Q, Pan L-L, Li C-H, Lu Y-L, Wang J-Q, Cai Y-L. Sea voyage training and motion sickness effects on working ability and life quality after landing. Aerosp Med Hum Perform. 2021; 92(2):9298.


Asunto(s)
Personal Militar , Mareo por Movimiento/fisiopatología , Mareo por Movimiento/psicología , Calidad de Vida , Navíos , Adolescente , Adulto , China/epidemiología , Humanos , Incidencia , Masculino , Mareo por Movimiento/epidemiología , Prevalencia , Encuestas y Cuestionarios
5.
Appl Ergon ; 92: 103312, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33338973

RESUMEN

Profile of cybersickness and balance disturbance induced by virtual ship motion alone and in combination with galvanic vestibular stimulation (GVS) remained unclear. Subjects were exposed to a ship deck vision scene under simulated Degree 5 or 3 sea condition using a head-mounted virtual reality display with or without GVS. Virtual ship motion at Degree 5 induced significant cybersickness with symptom profile: nausea syndrome > central (headache and dizziness) > peripheral (cold sweating) > increased salivation. During a single session of virtual ship motion exposure, GVS aggravated balance disturbance but did not affect most cybersickness symptoms except cold sweating. Repeated exposure induced cybersickness habituation which was delayed by GVS, while the temporal change of balance disturbance was unaffected. These results suggested that vestibular inputs play different roles in cybersickness and balance disturbance during virtual reality exposure. GVS might not serve as a potential countermeasure against cybersickness induced by virtual ship motion.


Asunto(s)
Mareo por Movimiento , Navíos , Estimulación Eléctrica , Humanos , Inmersión , Movimiento (Física) , Sensación
6.
International Eye Science ; (12): 946-951, 2021.
Artículo en Inglés | WPRIM (Pacífico Occidental) | ID: wpr-876733

RESUMEN

@#AIM: To evaluate and compare the quality of life of patients submitted to phacoemulsification combined with goniosynechialysis(PPI+GSL)and trabeculectomy, and analyze the potentially involved variables.<p>METHODS: A perspective, randomized case-control study was conducted. Patients with acute primary angle-closure glaucoma(ACG)and early cataracts underwent PPI+GSL implantation(group A, <i>n</i>=29)and trabeculectomy(group B, <i>n</i>=30). The quality of life was assessed using the National Eye Institute 25-Item Visual Function Questionnaire(NEI-VFQ-25)before and 6mo after surgery. Intraocular pressure(IOP), best corrected visual acuity(BCVA), review frequency and the basic characteristics were recorded simultaneously.<p>RESULTS: Compared with preoperative status, the IOP in both groups was significantly decreased(all <i>P</i><005), and the BCVA was significantly increased in group A(<i>P</i><0.05), while did not differ significantly in group B(<i>P</i>>0.05). Besides, group B presented higher review frequency than group A(<i>P</i><0.05). Moreover, significant increases in postoperative scores were founded in the two groups respectively(all <i>P</i><0.05). Compared with group B, group A had better postoperative performance in items of general vision, ocular pain, long-distance activities, social functioning and role limitations(all <i>P</i><0.05). Besides, group A presented significantly higher net increases in postoperative total scores than group B(<i>P</i><0.05), which was positively associated with the degree of the BCVA recovery and negatively associated with review frequency(<i>R</i><sup>2</sup>=0.48, <i>F</i>=5.00, <i>P</i><0.05).<p>CONCLUSION: APACG patients with early cataracts, PPI+GSL determines better improvement in quality of life compared to trabeculectomy.

7.
J Pharmacol Exp Ther ; 373(2): 248-260, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-32165443

RESUMEN

It has been identified that arginine vasopressin (AVP), vasopressin receptor 2(V2R), and the aquaporin 2 (AQP2) signaling pathway in the inner ear play important roles in hearing and balance functions through regulating the endolymph equilibrium; however, the contributions of this signaling pathway to the development of motion sickness are unclear. The present study was designed to investigate whether the activation of the AVP-V2R-AQP2 signaling pathway in the inner ear is involved in the induction of motion sickness and whether mozavaptan, a V2R antagonist, could reduce motion sickness. We found that both rotatory stimulus and intraperitoneal AVP injection induced conditioned taste aversion (a confirmed behavioral index for motion sickness) in rats and activated the AVP-V2R-AQP2 signaling pathway with a responsive V2R downregulation in the inner ears, and AVP perfusion in cultured epithelial cells from rat endolymphatic sacs induced similar changes in this pathway signaling. Vestibular training, V2R antagonist mozavaptan, or PKA inhibitor H89 blunted these changes in the V2R-AQP2 pathway signaling while reducing rotatory stimulus- or DDAVP (a V2R agonist)-induced motion sickness in rats and dogs. Therefore, our results suggest that activation of the inner ear AVP-V2R-AQP2 signaling pathway is potentially involved in the development of motion sickness; thus, mozavaptan targeting AVP V2Rs in the inner ear may provide us with a new application option to reduce motion sickness. SIGNIFICANCE STATEMENT: Motion sickness affects many people traveling or working. In the present study our results showed that activation of the inner ear arginine vasopressin-vaspopressin receptor 2 (V2R)-aquaporin 2 signaling pathway was potentially involved in the development of motion sickness and that blocking V2R with mozavaptan, a V2R antagonist, was much more effective in reducing motion sickness in both rat and dog; therefore, we demonstrated a new mechanism to underlie motion sickness and a new candidate drug to reduce motion sickness.


Asunto(s)
Acuaporina 2/fisiología , Arginina Vasopresina/fisiología , Oído Interno/fisiología , Mareo por Movimiento/etiología , Receptores de Vasopresinas/fisiología , Animales , Antagonistas de los Receptores de Hormonas Antidiuréticas/uso terapéutico , Arginina Vasopresina/sangre , Benzazepinas/uso terapéutico , Células Cultivadas , Proteínas Quinasas Dependientes de AMP Cíclico/antagonistas & inhibidores , Perros , Femenino , Masculino , Mareo por Movimiento/tratamiento farmacológico , Ratas , Ratas Sprague-Dawley , Transducción de Señal/fisiología
8.
Neuropsychiatr Dis Treat ; 16: 25-33, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32021196

RESUMEN

PURPOSE: The purpose was to investigate the differences in spontaneous functional connectivity (FC) of the primary visual cortex (V1) between patients with neovascular glaucoma (NVG) and healthy controls (HCs) using resting-state functional magnetic resonance imaging data. METHODS: A total of 18 patients with NVG (nine males and nine females) and 18 HCs with similar age and sex background were enrolled in the study and inspected using resting-state functional magnetic resonance imaging. The differences in FC of the V1 between the two groups were compared using the independent samples t-test. We used the receiver operating characteristic (ROC) curve to compare the average FC values of NVG subjects with those of HCs. RESULTS: FC in the left V1 and right fusiform gyrus, bilateral cuneus, and left precuneus was significantly decreased in the NVG group compared with that reported in the HC group. Meanwhile, patients with NVG presented increased FC between the right V1 and bilateral middle frontal gyrus. However, they also exhibited declining FC between the right V1 and left precuneus, and bilateral cuneus. The ROC curve analysis of each brain region indicated that the accuracy of the area under the ROC curves regarding NVG was excellent. CONCLUSION: NVG involves aberrant FC in the V1 in different brain areas, including the visual-related and cognitive-related regions. These findings may assist in unveiling the underlying neural mechanisms of impaired visual function in NVG.

9.
Genes Cancer ; 10(5-6): 160-170, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31798768

RESUMEN

Carboxypeptidase E (CPE), a prohormone processing enzyme, is a 476- amino acid protein with a signal peptide in its N-terminus and is expressed in the nervous and the endocrine systems. Recent evidence indicate CPE plays various non-enzymatic roles in the endocrine and nervous systems and in various cancers. Besides wild type (WT) CPE, a 40-kDa CPE protein that localizes in the nucleus and cytoplasm has been described in embryonic mouse brain. In this study we have cloned this CPE variant encoding the 40kDa CPE-ΔN protein from human cancer cells. RACE assay and sequence analysis confirmed existence of this CPE variant mRNA, which has 198 nucleotides removed within the first exon and 589 nucleotides from the 3'-UTR, respectively, compared to WT-CPE mRNA. Bioinformatic analysis revealed that this CPE variant mRNA has a shortened open reading frame, which starts coding from the 3rd ATG relative to WT-CPE mRNA and encodes a 40kDa N-terminus truncated CPE protein. RT-PCR and Western blot analysis showed that 40kDa CPE-ΔN is expressed in multiple cancer cell lines and tumor tissues. Overexpression of this 40kDa CPE-ΔN variant up-regulated expression of multiple metastatic genes encompassing different signaling pathways, suggesting potentially an important role of CPE-ΔN in tumor metastasis.

10.
J Med Entomol ; 56(6): 1734-1738, 2019 10 28.
Artículo en Inglés | MEDLINE | ID: mdl-31283827

RESUMEN

Surveillance for blood-fed female mosquitoes was performed between August 2015 and February 2016 at sites along the periphery of the Aripo Savannas Environmentally Reserve (ASSR) located in northeastern Trinidad, West Indies. We collected engorged female mosquitoes representing 13 species. DNA extractions from dissected abdomens were subjected to PCR amplification with three primer pairs targeting the mitochondrial cytochrome oxidase I and cytochrome b gene sequences. High-quality sequence information and host identification were obtained for 42 specimens representing eight mosquito species with at least one primer combination. A broad range of vertebrates including humans were identified, but the majority were nonhuman mammals, both domestic and wild. Domestic dogs were the most common host and may represent potential sentinel species for monitoring local enzootic arbovirus activity in Trinidad. Culex declarator Dyer and Knab and Culex nigripalpus Theobald were the most common blood-fed mosquito species comprising 79.1% of the total number identified. These species obtained blood meals from birds, nonhuman mammals, and human hosts, and therefore pose significant risks as potential bridge vectors for epizootic arbovirus transmission in the ASSR area as well as other sylvan areas in Trinidad. These data represent the first such results for Trinidad.


Asunto(s)
Culicidae/fisiología , Cadena Alimentaria , Mosquitos Vectores/fisiología , Animales , Arbovirus , Aves , Dieta , Conducta Alimentaria , Femenino , Humanos , Mamíferos , Trinidad y Tobago
11.
Org Biomol Chem ; 17(16): 4061-4072, 2019 04 17.
Artículo en Inglés | MEDLINE | ID: mdl-30951069

RESUMEN

Gabosines and their natural analogues, belonging to C7 carbasugars, have attracted great attention in synthesis due to their rich structural variety and promising biological activities. A new diversity-oriented approach for the gabosine-type carbasugars based on a tunable regioselective aldol cyclization of flexible precursor 2 is explored. Two cyclization modes (A and B) of the precursor can be well controlled by switching promoters to selectively produce two resulting cyclohexa(e)nones 3 and 10, both of which are versatile intermediates for various C7 carbasugars. After the conversion of 3 to eight natural carbasugars, the utility of intermediate 10 is illustrated by the first synthesis of (-)-gabosine L, as well as the new synthesis of (-)-gabosine A, (-)-gabosine B, (-)-gabosine N and (-)-gabosine O. The chemical structure and the absolute configuration of (-)-gabosine L are confirmed by its total synthesis.

12.
Int J Ophthalmol ; 12(4): 542-548, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31024804

RESUMEN

AIM: To determine the progression of parameters from optical coherence tomography (OCT) in chronic elevated intraocular pressure (IOP) monkeys. METHODS: A chronic elevated IOP model of rhesus monkeys was induced by laser photocoagulation. Representative OCT parameters, including the average and four-quadrant retinal nerve fiber layer (RNFL) thickness, and parameters from optic nerve head (ONH) analysis were collected before and after laser treatments biweekly for up to 28wk. The performance of each parameter for early progression detection was analyzed. The progressive trends toward elevated IOP were analyzed using a linear mixed-effects model. RESULTS: There were 10 successfully maintained high IOP eyes in 7 monkeys. The follow-up time was 24±5.37wk. With cumulative IOP elevation, the cup area, rim area and C/D area ratio were statistically significantly changed as early as 2wk after elevated IOP induction (P<0.05). The quadrant RNFL thickness changed at 6wk after high IOP induction, and the superior and inferior RNFL thicknesses exhibited more obvious reductions than other quadrants. The average RNFL thickness was the last one to show a significant decrease at 8wk. CONCLUSION: The parameters of ONH are most sensitive to elevated IOP in a primate glaucomatous model. These findings suggest that we should focus on those parameters instead of RNFL thickness in patients with elevated IOP, as they might present with earlier glaucomatous changes.

13.
International Eye Science ; (12): 1488-1491, 2018.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-731265

RESUMEN

@#AIM: To compare the refraction error(RE)3mo after phacoemulsification combined with intraocular lens implantation(PHACO+IOL)between patients with acute primary angle-closure glaucoma(APACG)with cataract(APACG group)and patients with simple cataract(cataract group), and the biological parameters of the eye(axial length,corneal curvature, anterior chamber depth)associated with the postoperative RE in the APACG and cataract groups. <p>METHODS: This was a prospective, non-randomized, case-control study. Each group had 30 cases(30 eyes). Intraocular pressure, axial length, corneal curvature, and anterior chamber depth were measured. The reserved refractive power was calculated using the SRK-II formula. Three months postoperatively, subjective RE was calculated as the postoperative refractive power which subtracted the preoperative reserved diopter(RE was considered as <-0.50D or >+0.50D; -0.50D to +0.50D not considered as RE). An independent sample <i>t</i>-test was used to compare the difference in RE between the two groups and to compare the differences among relevant parameters such as axial length, corneal curvature, and anterior chamber depth. Paired <i>t</i>-test was used to compare preoperative and postoperative parameters such as axial length, corneal curvature, and difference in anterior chamber depth. <p>RESULTS: Mean RE in the cataract group was -0.46D±0.46D, with 24 cases of myopic RE(80%)and 6 cases of hyperopic RE(20%). Mean RE in the APACG group was +0.56D±0.79D, with 9 cases of myopic RE(30%)and 21 cases of hyperopic RE(70%). The difference in RE between the two groups was statistically significant(<i>P</i><0.05). On comparison of pre- and postoperative biological parameters of the two groups, in the cataract group, there was a non-significant difference in pre- and postoperative axial length(23.55±0.47mm versus 23.56±0.48mm, respectively; <i>P</i>>0.05). In the APACG group, pre- and postoperative axial length was 21.71±0.46mm and 21.52±0.54mm, respectively; the difference was statistically significant(<i>P</i><0.05). In the both the cataract and APACG groups, postoperative anterior chamber depth was significantly higher than preoperative(4.09±0.38mm versus 2.71±0.24mm, in the cataract group, and 3.55±0.35mm versus 1.90±0.23mm, In the APACG group, respectively; both <i>P</i><0.05). In the cataract group and the APACG groups, pre- and postoperative average corneal curvature were not significantly different(43.93D±0.95D versus 43.92D±0.95D, in the cataract group, and 44.71D±0.84D versus 44.70D±0.9D, In the APACG group, respectively; <i>P</i>>0.05). On comparison of biological parameters between the two groups, postoperative ocular axial length shortening in the APACG group was statistically significant compared with the ocular axial changes in the cataract group(<i>P</i><0.05). The postoperative anterior chamber deepened markedly in the APACG group; this was statistically significant compared with the cataract group(<i>P</i><0.05).<p>CONCLUSION:Postoperative RE in patients with APACG and cataract who underwent PHACO+IOL is relatively large compared with patients with simple cataracts. These patients with APACG and cataract also show hyperopia drift, which is more significantly correlated with postoperative ocular axial length shortening and increased anterior chamber depth.

14.
Basic & Clinical Medicine ; (12): 63-68, 2018.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-664991

RESUMEN

Objective To explore the effect and molecular mechanism of miR-202 on the differentiation of 3T3-L1 preadipocyte .Methods Through lentivirus infected with 3T3-L1 preadipocytes , we set up the AMO-miR-202 group and the random control group , then, these cells were induced to differentiate , nine days later, differentiation was assessed by Oil Red O staining and we examined the mRNA expression of PPARγ2 and aP2 by RT-PCR method. We examined the mRNA expression of PPARγ2,aP2 and PGC1βby Western blot method .Results After packa-ging lentivirus with AMO-miR-202 and random sequence control miRNA through cell line 293T, 80%-90%cells with fluorescence were found under fluorescence microscope; After these two lentivirus respectively infected with 3T3-L1 preadipocytes, About 70%-80%cells with fluorescence were found under fluorescence microscope .Oil Red O staining test showed that these cells with Oil Red O stained bright red fat droplets of AMO-miR-202 group and PPARγ2 and aP2 mRNA expression in the AMO-miR-202 group significantly lower than control groups (P<0.05). Western blot assay showed that the protein expression of PGC 1βin the AMO-miRNA-202 group was significantly increased(P<0.05), but the expression of aP 2 and PPARγ2 was significantly decreased (P<0.01).However, the random control group and the adipocyte group had no significant effect on the above indexes .Conclusions miR-202 can promote the differentiation of 3T3-L1 preadipocyte by inhibiting the protein expression of PGC 1βand im-proving the protein expression of PPARγ2 and aP2.

15.
Guang Pu Xue Yu Guang Pu Fen Xi ; 36(7): 2042-7, 2016 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-30035875

RESUMEN

Searching for new energy source is one of the most important projects faced by the global, while the most ideal new energy source is solar cell. Near infrared quantum cutting luminescence method can doubly transfer large energy photon which is not sensitive to Si or Ge solar cell to small energy photon which is sensitive to Si or Ge solar cell. It can resolve the spectral mismatch problem and largely enhance solar cell efficiency. Therefore, it is significant. The concentration effect of near-infrared quantum cutting luminescence of Tm3+Bi3+∶YNbO4 phosphor is reported in present manuscript. Through the measurement of excitation and emission spectra, it is found that the Tm0.058Bi0.010Y0.932NbO4 powder phosphor has intense 1 820.0 nm near-infrared quantum cutting luminescence. Further analysis finds they are multi-photon quantum cutting luminescence induced by the cross-energy transfer process. The population of 1G4 energy level may be directly transferred to lower energy level mainly through {1G4­3H4, 3H6­3H5} and {1G4­3H5, 3H6­3H4} cross-energy transfer processes, i. e. one population of the 1G4 energy level may effectively lead to two populations, which are positioned at the 3H4 and 3H5 energy levels, respectively, mainly through {1G4­3H4, 3H6­3H5} and {1G4­3H5, 3H6­3H4} cross-energy transfer processes. This may also effectively lead to three populations of the 3F4 energy level through {3H4­3F4, 3H6­3F4} cross-energy transfer process from the 3H4 level and multi-phonon non-radiative relaxation from the 3H5 level, respectively. This results in the effective three-photon near-infrared quantum cutting of the 3F4­3H6 fluorescence of Tm3+ ion. It's also found that the sensitization action of Bi3+ ion to Tm3+ ion is very strong. The enhancement of the 1 820.0 nm near-infrared quantum cutting luminescence, of Tm0.058Bi0.010Y0.932NbO4 relative to Tm0.005Y0.995NbO4, is about 175.5 times, when excited by the 302.0 nm light. The present results are significant for the exploration of the next-generation multi-photon near-infrared quantum cutting germanium solar cell.

16.
Guang Pu Xue Yu Guang Pu Fen Xi ; 35(2): 315-9, 2015 Feb.
Artículo en Chino | MEDLINE | ID: mdl-25970884

RESUMEN

The present manuscript researches the near infrared quantum cutting luminescence phenomena of Yb3+ ion in YVO4 crystal matrix The luminescence spectra, excitation spectra and fluorescence lifetimes were measured. It was found that the excitation of YVO4 crystal matrix energy band by 322.0 nm light can result in the effective secondary cooperative energy transfer of Yba+ ion from the YVO4 crystal matrix It results in the intense 985.5 nm 2F(5/2)-->2F(7/2) near infrared quantum cutting luminescence of Yb3+ ion. Meanwhile, the 430.O nm luminescence intensity of YVO4 crystal matrix decreases greatly. From the experimental measurements, it was found that the lifetime of 430.0 nm fluorescence of (A) Yb(1.5) : YVO4 crystal is tauA = 3.785 s and that of (B) YVO4 crystal is tauB=22.72 s. It was found also that the theoretical efficiency up limit of quantum cutting of (A) Yb(1.5) : YVO4 crystal is about eta1.5%=183-3%.

17.
BMC Cancer ; 14: 479, 2014 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-24989027

RESUMEN

BACKGROUND: Altered expression of astrocyte elevated gene-1 (AEG-1) is associated with tumorigenesis and progression. The present study aimed to investigate the clinical and prognostic significance of AEG-1 expression in pancreatic ductal adenocarcinoma (PDAC). METHODS: Quantitative reverse transcriptase polymerase chain reaction (qRT-PCR) and Western blot analyses were employed to assess AEG-1 expression in three pancreatic cancer cell lines and normal pancreatic duct epithelial cells. qRT-PCR and immunohistochemical analyses were performed to detect AEG-1 expression in ten pairs of PDAC and normal pancreas tissues. Immunohistochemistry was then used to examine AEG-1 expression in paraffin-embedded tissues obtained from 105 patients, and its association with clinicopathological parameters including cancer classification was examined. Kaplan-Meier analysis was performed to study the survival rates of patients. RESULTS: Expression of AEG-1 mRNA and protein was markedly higher in pancreatic cancer cell lines than that in the normal pancreatic duct epithelial cells. AEG-1 expression was evidently upregulated in PDAC tissues compared to that of the matched distant normal pancreas tissues. qRT-PCR data revealed that the tumor/non-tumor ratio of AEG-1 expression was >1.5-fold (up to 6.5-fold). Immunohistochemical data showed that AEG-1 protein was detected in 98.09% (103/105) of PDAC tissues; and they were found to be associated with tumor size (P = 0.025), advanced clinical stage (P = 0.004), T classification (P = 0.006), N classification (P = 0.003), and M classification (P = 0.007). Furthermore, Kaplan-Meier analysis showed that patients with high AEG-1-expressed PDAC had shorter overall survival. A multivariate Cox regression analysis revealed that clinical stage, T classification, and AEG-1 expression were the independent prognostic predictors for PDAC. CONCLUSIONS: This study suggests that AEG-1 protein was highly expressed in PDAC and associated with poor prognosis of the patients.


Asunto(s)
Biomarcadores de Tumor/genética , Biomarcadores de Tumor/metabolismo , Carcinoma Ductal Pancreático/patología , Moléculas de Adhesión Celular/genética , Moléculas de Adhesión Celular/metabolismo , Neoplasias Pancreáticas/patología , Anciano , Carcinoma Ductal Pancreático/genética , Línea Celular Tumoral , Femenino , Regulación Neoplásica de la Expresión Génica , Humanos , Masculino , Proteínas de la Membrana , Persona de Mediana Edad , Neoplasias Pancreáticas/genética , Proteínas de Unión al ARN , Análisis de Supervivencia
18.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-233791

RESUMEN

<p><b>OBJECTIVE</b>To assess the efficiency of carbon nanoparticle in guiding level VI lymphadenectomy and parathyroid preservation in thyroidectomy for carcinoma.</p><p><b>METHODS</b>One hundred and nine patients with well differentiated thyroid carcinoma, in whom thyroidectomy and bilateral lymphadenectomy for level VI were carried out at the same time, were prospectively studied. Fourty-five cases received carbon nanoparticle injecion in thyroid consistitued trial group, while sixty-four underwent conventional surgery as control group. The numbers of total dissected lymph nodes, metastasis lymph nodes, black-stained lymph nodes, detected parathyroids and mistakenly removed parathyroids were counted respectively. The PTH levels were measured at 1 d, 5 d and 30 d after surgery, respectively. Student's t test and Chi-square analysis were used for analyzing data.</p><p><b>RESULTS</b>The number of lymph node found in the trial group in level VI was checked out as (9.7 ± 1.7) each side, whereas that of the control group was (6.7 ± 1.9) each side. The discrepancy of two groups was statistical meaningful (t = 23.14, P < 0.001). The discrepancy of the rate of lymph node black-stained 90.5% (738/815), incidence of metastasis of the black-stained lymph nodes 45.9% (339/738) and that without black-staining 13.0% (10/77), was statistical meaningful (χ(2) = 30.91, P < 0.001). On average, the trial group showed (1.8 ± 0.9) parathyroid each side, and had 5.9% (5/84) of mistakenly removed incidence , on contrary, the control group showed (1.8 ± 1.0) parathyroid each side, and had 8.2% (11/134) of mistakenly removed incidence averagely as well. The discrepancy of two groups was statistical meaningful. In the trial group, the amount of PTH 1 d, 5 d and 30 d postoperatively were 7.30, 11.19 and 30.50 ng/L respectively, while that of the control group were 7.51, 10.90 and 28.30 ng/L respectively. The amount discrepancy between the two groups was not differences. No permanent recurrent nerve paralysis was found in both groups.</p><p><b>CONCLUSION</b>Carbon nanoparticle may improve the detected rate of metastasis lymph nodes, but may not be helpful to the prevention of postoperative hypoparathyrosim.</p>


Asunto(s)
Humanos , Carbono , Carcinoma , Hipoparatiroidismo , Escisión del Ganglio Linfático , Ganglios Linfáticos , Metástasis Linfática , Nanopartículas , Nanotubos de Carbono , Glándulas Paratiroides , Periodo Posoperatorio , Coloración y Etiquetado , Neoplasias de la Tiroides , Terapéutica , Tiroidectomía , Métodos
19.
Guang Pu Xue Yu Guang Pu Fen Xi ; 33(7): 1734-8, 2013 Jul.
Artículo en Chino | MEDLINE | ID: mdl-24059164

RESUMEN

In the present paper, the absorption spectra of Ho3+ (0.5 mol%)-doped oxyfluoride glass (FOG) sample and Ho3+ (0.5 mol%)-doped oxyfluoride vitroceramics (FOV) sample were measured through experiment. The authors calculated the intensity parameters omega 2, 4, 6 of the two materials according to J-O theory, and analyzed the possible reason for the difference between the two materials on the intensity parameters. After that the authors calculated oscillator strength, spontaneous radiative transition rate, branching ratio and integrated emission cross section and some other spectroscopic parameters of several excited states and then made a comparative analysis of the two materials based on these spectroscopic parameters. The authors found that the oscillator strength of trivalent holmium iron in FOV is about the same with the oscillator strength in YAlO3 and is similar to oscillator strength in FOG, while slightly larger than in that LBTAF and much larger than that in LaF3 and ZBLAN. By analyzing the calculated spectroscopic parameters, it can be found that some transitions, especially 5I7 --> 5I8, 5F5 --> 5I8 etc., have a relatively large oscillator strengths(larger than 10(-6)) and large integrated emission cross sections(larger than 10(-18) cm). These transitions have the conditions to form laser passages, so they are worth a lot of attention. At last, application prospects of several strong luminescence transitions were concluded.

20.
Huan Jing Ke Xue ; 34(6): 2399-406, 2013 Jun.
Artículo en Chino | MEDLINE | ID: mdl-23947062

RESUMEN

In this study, 23 groups of suited typical soil-wheat grain samples were collected from different locations of Beijing city (central city, suburban plain and exurban plain), the accumulation, chemical forms and bioavailability of heavy metals in arable soils under different human activity intensity were analyzed, and their source identifications and health risk were discussed. The results showed that (1) Urban soils exhibited Pb contamination with an average concentration (35.59 mg x kg(-1)) above the WHO limit, probably due to the emission of traffic activities and industrial processes. In addition, long-term sewage irrigation and other agricultural activities led to local metal contamination in the suburban agricultural soils. (2) Cu, Zn and Pb were predominantly associated with the residual (35%-75%) and organic (23%-53%) fractions, followed by Fe/Mn oxide (1%-19%), and very small proportion of carbonate (n. d.-5%) and exchangeable (n. d.-2%) fraction. Furthermore, compared with the suburban agricultural soils, Pb, Zn and Cu in the urban agricultural soils showed higher mobility, whereas the exurban agricultural soils presented the lowest mobility. For Cd, the order was contrary. Besides, Cd showed the highest bioavailability among the four metals in suburban and exurban arable soils due to its considerable proportion of exchangeable (13% -31%) and carbonate fractions (11%-27%). (3) Cd and Zn contents in wheat grains were largely dependent on the Fe/Mn ox. fractions in the studied soils (P < 0.05, r were 0.43-0.7). (4) Pb and Zn concentrations in wheat grains in some of the urban and suburban agricultural soils were above the standard limit, which might bring potential risk for the health of the local residents.


Asunto(s)
Productos Agrícolas , Monitoreo del Ambiente , Metales Pesados/análisis , Contaminantes del Suelo/análisis , Fraccionamiento Químico , China , Ciudades , Productos Agrícolas/crecimiento & desarrollo , Metales Pesados/química , Suelo/química
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