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1.
J Colloid Interface Sci ; 670: 798-807, 2024 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-38789354

RESUMEN

Nitrate in surface and underground water caused systematic risk to the ecological environment. The electrochemically reduction of nitrate into ammonia (NO3RR), offering a sustainable route for nitrate containing wastewater treatment and ammonia fertilizer conversion. Exploration of catalyst with improved catalytic activity with lower energy barriers is still challenging. Here, we report a copper nitride (Cu3N) catalyst with moderate *NOx and *H2O intermediates adsorptions showed enhanced NO3RR performance. Density functional theory calculations reveals that the unique electronic structure of Cu3N provides efficient active sites for NO3RR, thus enabled balanced adsorption of *NO3 and *H2O (ΔE descriptor), sufficient active hydrogen, and moderate intermediate (*NO3 â†’ HNO3, *NH2→*NH3) adsorption energy. Notably, the in-situ analysis technology revealed potential-driven reconstruction and rehabilitation of Cu3N, forming possible nitrogen vacancy, thus implied for better mechanism understanding. The NO3RR activity of Cu3N surpasses that of most recent catalysts and demonstrates superior stability and implies the application for NH4+ fertilizer recovery, which maintaining an NH3 Faradaic efficiency of 93.1 % and high yield rate of 2.9 mg cm2h-1 at -0.6 V versus RHE. These findings broaden the application scenarios of Cu3N catalyst for ammonia synthesis and provide strategy on improving NO3RR performance.

2.
Small ; : e2311249, 2024 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-38482932

RESUMEN

Host-guest catalyst provides new opportunities for targeted applications and the development of new strategies for preparing host-guest catalysts is highly desired. Herein, an in situ solvent-free approach is developed for implanting ZrW2 O7 (OH)2 (H2 O)2 nanorods (ZrW-NR) in nitro-functionalized UiO-66(Zr) (UiO-66(Zr)-NO2 ) with hierarchical porosity, and the encapsulation of ZrW-NR enables the as-prepared host-guest catalyst remarkably enhanced catalytic performance for both for oxidative desulfurization (ODS) and acetalization reactions. ZrW-NR@UiO-66(Zr)-NO2 can eliminate 500 ppm sulfur within 9 min at 40 °C in ODS, and can transform 5.6 mmol benzaldehyde after 3 min at room temperature in acetalization reaction. Its turnover frequencies reach 72.3 h-1 at 40 °C for ODS which is 33.4 times higher than UiO-66(Zr)-NO2 , and 28140 h-1 for acetalization which is the highest among previous reports. Density functional theory calculation result indicates that the W sites in ZrW-NR can decompose H2 O2 to WVI -peroxo intermediates that contribute to catalytic activity for the ODS reaction. This work opens a new solvent-free approach for preparing MOFs-based host-guest catalysts to upgrade their redox and acid performance.

3.
Dalton Trans ; 52(43): 15968-15973, 2023 Nov 07.
Artículo en Inglés | MEDLINE | ID: mdl-37846746

RESUMEN

Insights into the relationship between the crystal structure and activity of metal-organic frameworks (MOFs) are meaningful to investigate the potential properties of pristine MOFs for targeted catalytic reactions. Herein, we develop a high-efficiency method for boosting the oxidative desulfurization (ODS) activity of Ti-MOF in the presence of H+. The ODS activity of pristine Ti-MOF prepared via a solvothermal approach is very poor at a low reaction temperature but can be enhanced in the presence of H+. Ti-MOF in the presence of H+ shows ultrahigh ODS activity that can eliminate 1000 ppm sulfur after 7 min at 30 °C with no catalytic activity loss after recycling 11 times. The turnover frequency value reaches 12.4 h-1 at 30 °C, surpassing all the previously reported Ti-MOFs as ODS catalysts even at high temperatures. Characterization and quenching experimental results indicate that more uncoordinated Ti sites can be formed from slight damage to the structure of Ti-MOF during the catalytic reaction, and such exposed Ti sites can easily react with H+ and H2O2 to form Ti-hydroperoxo active species that determine the upgradation of ODS activity. This work provides a significant way to upgrade the catalytic activity of pristine Ti-MOFs for future application.

4.
Small ; 19(38): e2301035, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37226376

RESUMEN

Stable platforms of host-guest catalysts are indispensable in the field of heterogeneous catalysis, however, clarifying the specific effect of host remains challenging. Herein, polyoxometalate (POM) is encapsulated in three types of UiO-66(Zr) with different controlled densities of defects by the aperture opening and closing strategy at ambient-temperature. It is found that catalytic activity of POM for oxidative desulfurization (ODS) at room temperature is turned on when encapsulated in the defective UiO-66(Zr), and the sulfur oxidation efficiency shows an obvious increasing trend (from 0.34 to 10.43 mmol g-1 h-1 ) with the increased concentration of defects in UiO-66(Zr) host. The as-prepared catalyst with the most defective host displays ultrahigh performance which removed 1000 ppm sulfur with exceptionally diluted oxidant at room-temperature within 25 min. The turnover frequency can reach 620.0 h-1 at 30 °C, which surpassed all the reported MOFs based ODS catalysts. A substantial guest/host synergistic effect mediated by the defective sites in UiO-66(Zr) is responsible for the enhancement. Density functional theory calculations reveal that OH/OH2 capped on the open Zr sites of host UiO-66(Zr) can decompose H2 O2 to OOH group and enables the formation of WVI -peroxo intermediates that determine the ODS activity.

5.
Dalton Trans ; 52(22): 7695-7700, 2023 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-37200000

RESUMEN

Functionalized metal-organic frameworks (MOFs) have been used in a wide range of applications. Although the development of functionalized MOFs with plentiful open metal sites (defects) provides an avenue for targeted reactions, creating such defects remains challenging. Herein, a UiO-type MOF with hierarchical porosity and plentiful Zr-OH/OH2 sites (capping 35% Zr coordination sites) was synthesized within 40 min by a solid-phase synthesis route without the use of solvent and template. The optimal sample converted 5.7 mmol benzaldehyde to (dimethoxymethyl)benzene within 2 min at 25 °C. The turnover frequency number and activity per unit mass reached 2380 h-1 and 8568 mmol g-1 h-1, respectively, outperforming all previously reported catalysts at room temperature. This excellent catalytic activity was correlated with the defect density in functionalized UiO-66(Zr) and the accessibility of plentiful Zr-OH/OH2 sites as acid sites.

6.
Inorg Chem ; 62(10): 4248-4259, 2023 Mar 13.
Artículo en Inglés | MEDLINE | ID: mdl-36857420

RESUMEN

Creation of rich open metal sites (defect) on the nodes of metal-organic frameworks (MOFs) is an efficient approach to enhance their catalytic performance in heterogeneous reactions; however, direct generation of such defects remains challenging. In this contribution, we developed an in situ green route for rapid fabrication of defective MOF-808(Zr) with rich Zr-OH/OH2 sites (occupying 25% Zr coordination sites) and hierarchical porosity without the assistance of formic acid and solvent. The optimal MOF-808(Zr) not only displayed superior activity in oxidative desulfurization (ODS) for removing 1000 ppm sulfur at ambient temperature within 20 min but also could convert 3.8 mmol of benzaldehyde to (dimethoxymethyl)benzene within 90 s at 30 °C. The turnover frequencies reached 45.4 h-1 for ODS and 3451 h-1 for acetalization, outperforming the most reported MOF-based catalysts. Theoretical calculation and experimental results show that the formed Zr-OH/OH2 can react with H2O2 to generate peroxo-zirconium species, which readily oxidize the sulfur compound. Our work provides a new approach to the synthesis of defect-rich MOF-808(Zr) with the accessibility of active sites for target reactions.

7.
Angew Chem Int Ed Engl ; 60(37): 20318-20324, 2021 Sep 06.
Artículo en Inglés | MEDLINE | ID: mdl-34121275

RESUMEN

Design of single-site catalysts with catalytic sites at atomic-scale and high atom utilization, provides new opportunities to gain superior catalytic performance for targeted reactions. In this contribution, we report a one-pot green approach for in situ implanting of single tungsten sites (up to 12.7 wt.%) onto the nodes of defective UiO-66(Zr) structure via forming Zr-O-W bonds under solvent-free condition. The catalysts displayed extraordinary activity for the oxidative removal of sulfur compounds (1000 ppm S) at room temperature within 30 min. The turnover frequency (TOF) value can reach 44.0 h-1 at 30 °C, which is 109.0, 12.3 and 1.2 times higher than that of pristine UiO-66(Zr), WO3 , and WCl6 (homogeneous catalyst). Theoretical and experimental studies show that the anchored W sites can react with oxidant readily and generate WVI -peroxo intermediates that determine the reaction activity. Our work not only manifests the application of SSCs in the field of desulfurization of fuel oil but also opens a new solvent-free avenue for fabricating MOFs based SSCs.

8.
Environ Pollut ; 274: 115866, 2021 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-33277062

RESUMEN

Selenium (Se) and arsenic (As) are toxic contaminants in surface water and drinking water. The human body needs little quantity of Se, but too high dose is not allowed. Metal oxides such as iron oxides were used for adsorption or co-precipitation removal of As from water. However, the regeneration and stability problems of metals oxides sorbents are unsatisfactory , and there is not enough adsorbent for Se removal from water also. We developed the acrylic amine fiber (AAF) for adsorption reomval of Se and As from water and systematically studied the influenced factors. Batch experiments were conducted for investigating the adsorption edges, while column filtration tests were employed for dynamic application edges. At neutral pH, the Langmuir isotherm fittings gave the maximum adsorption capacities of As(V), As(III), Se(VI) and Se(IV) are 270.3, 40.5, 256.4, and 158.7 mg/g, respectively. Effects of co-existing inorganic anions on As(V) and Se(VI) adsorption using AAF gave the order of PO43- > SO42- > NO3- > SiO32-, while different organic acids obey the order of citric acid > oxalic acid > formic acid. Fourier transform infrared analysis showed the PO43- and SO42- competition mechanisms are electrostatic repulsions, while the competition of organic acids derived from acid-base reaction between the carboxyl group and the amino group. Column filtration and regeneration results showed that the spent AAF can be regenerated using 0.5 mol/L HCl solution and reused with no much decrease of adsorption capacity.


Asunto(s)
Arsénico , Selenio , Contaminantes Químicos del Agua , Purificación del Agua , Adsorción , Aminas , Arsénico/análisis , Humanos , Concentración de Iones de Hidrógeno , Cinética , Agua , Contaminantes Químicos del Agua/análisis
9.
ACS Appl Mater Interfaces ; 9(40): 34937-34943, 2017 Oct 11.
Artículo en Inglés | MEDLINE | ID: mdl-28920674

RESUMEN

The control of defects in crystalline materials has long been of significance since the defects are correlated with the performances of the materials. Yet such control remains a challenge for metal-organic frameworks (MOFs), which are usually well-crystallized under hydro-/solvothermal conditions. In this contribution, we demonstrate for the first time how to increase the defects of MOF via a facile and green approach as exemplified in the context of solvent-free synthesis of UiO-66(Zr). Such increase of defects leads to drastic enhancement of catalysis performance when compared to UiO-66(Zr) prepared from conventional hydro-/solvothermal synthesis. Our work therefore not only opens a new door for boosting the catalytic activities of MOFs but also contributes a new approach to control the defects in crystalline materials for various applications.

10.
Chemphyschem ; 18(14): 1903-1908, 2017 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-28437581

RESUMEN

Oxidative desulfurization is considered to be one of the most promising methods for producing ultra-low-sulfur fuels because it can effectively remove refractory sulfur-containing aromatic compounds under mild conditions. In this work, the oxidative desulfurization performance over UiO-66(Zr) is greatly enhanced by Ti ion exchange. This strategy is not only efficient for UiO-66(Zr) with crystal defects but also for UiO-66(Zr) with high crystallinity. In particular, the performance of UiO-66(Zr) with high crystallinity in the oxidative desulfurization of dibenzothiophene can be improved more than 11-fold, which can be mainly attributed to the introduction of active Ti sites.

11.
Dalton Trans ; 44(19): 9209-20, 2015 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-25907670

RESUMEN

In this work, three isomeric benzenedicarboxylates, 1,2-benzenedicarboxylic acid (o-H2bdc), 1,3-benzenedicarboxylic acid (m-H2bdc), and 1,4-benzenedicarboxylic acid (p-H2bdc) have been utilized as the ancillary ligands to perform a systematic study on the structural diversity of mixed-ligand frameworks. The solvothermal reactions of Co(NO3)2 with these aromatic acids and the primary ligand 4,4'-bis(imidazolyl)biphenyl (bibp) afford three novel coordination polymers, {[Co6(bibp)3(o-bdc)6(H2O)](CH3CN)1.5}∞ (1), [Co(bibp)(m-bdc)]∞ (2), and [Co(bibp)(p-bdc)]∞ (3). Owing to the different orientations of the carboxylate groups, the benzenedicarboxylates adopt various bridging modes to connect the Co(II) ions into a series of 1D carboxylate∩cobalt architectures based on the 1D chain, binuclear and single-ion magnetic units, respectively. These 1D architectures are further decorated by the bibp ligand to afford a 1D belt for , 2D double-bridging (4,4) sheet for 2, and an unusual 3D dmp framework for 3. Significantly in 3, three equivalent frameworks are interlocked with each other to represent an unprecedented three-fold interpenetrating dmp network. The structural diversity indicates that the benzenedicarboxylate plays an essential role in the assembly of mixed-ligand frameworks, and the orientation of the carboxylate group exerts an important influence on the nucleation, dimensionality and also interpenetration. Furthermore, the magnetic properties of 1 and 2 have been studied by fitting the experimental data as possible, and the magneto-structural correlation of 2 has also been well discussed. Importantly, CoO and Co3O4 were obtained from the controllable thermolysis of crystals of 1 via simple calcination treatment under different gas environments. The as-synthesized cobalt oxides display good crystallinity and appear as micro- or nanoparticles, which can be applied as supercapacitor electrodes as demonstrated by their energy storage performance in 2 M KOH electrolyte.

12.
Surg Radiol Anat ; 35(1): 49-53, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22744308

RESUMEN

PURPOSE: The aim was to provide anatomical data for local blocking treatment of de Quervain's disease through investigating features and classification of the first extensor groove on the radial styloid process. METHODS: Two hundred and eighty-four specimens of the intact distal extremity of dry radii from Chinese corpses were investigated and measured systematically in this study. Morphological features of the extensor grooves on the radial styloid process were observed by visual inspection. Correlation parameters of variability were measured with a vernier caliper. RESULTS: The study showed that the most prevalent group was Type I (the extensor groove that was deep and divided into two sub-grooves by a tiny bony ridge) accounting for 63.73 % (181 specimens). Seventy-nine specimens belonged to Type II (the extensor groove without the tiny bony ridge) accounting for 27.82 % and 24 specimens belonged to Type III (almost without any extensor groove on the radius) accounting for 8.45 %. The distance between the processus of the palmar bony ridge and the processus of the dorsal bony ridge (defined as AC) was 11.55 ± 1.32 mm. The distance between the processus of the palmar bony ridge and the sharp point of the styloid process of the radius (defined as AB) was 17.09 ± 1.99 mm. CONCLUSIONS: The extensor groove could provide a subjective safe operation range for the steroid injections, which could be defined depending on the bony landmarks, which are easy to identify in the body surface. This anatomical variation is important in the management of de Quervain's disease.


Asunto(s)
Pueblo Asiatico , Radio (Anatomía)/anatomía & histología , Articulación de la Muñeca/anatomía & histología , Análisis de Varianza , Cadáver , Enfermedad de De Quervain/patología , Enfermedad de De Quervain/fisiopatología , Femenino , Humanos , Masculino
13.
Chinese Medical Journal ; (24): 3222-3227, 2013.
Artículo en Inglés | WPRIM (Pacífico Occidental) | ID: wpr-354505

RESUMEN

<p><b>BACKGROUND</b>It has been widely demonstrated that endothelial progenitor cells are involved in several diseases and that they have therapeutic implications. In order to define the altered pulmonary vascular homeostasis in chronic obstructive pulmonary disease, we sought to observe the level and functions of circulating endothelial progenitor cells in patients with chronic obstructive pulmonary disease.</p><p><b>METHODS</b>The total study population included 20 patients with chronic obstructive pulmonary disease and 20 control subjects. The number of circulating endothelial progenitor cells (CD34(+)/CD133(+)/VEGFR-2(+) cells) was counted by flow cytometry. Circulating endothelial progenitor cells were also cultured in vitro and characterized by uptake of DiIacLDL, combining with UEA-I, and expression of von Willebrand factor and endothelial nitric oxide synthase. Adhesion, proliferation, production of nitric oxide, and expression of endothelial nitric oxide synthase and phosphorylated-endothelial nitric oxide synthase were detected to determine functions of circulating endothelial progenitor cells in patients with chronic obstructive pulmonary disease.</p><p><b>RESULTS</b>The number of circulating endothelial progenitor cells in the chronic obstructive pulmonary disease group was lower than in the control group: (0.54 ± 0.16)% vs. (1.15 ± 0.57)%, P < 0.05. About 80% of adherent peripheral blood mononuclear cells cultured in vitro were double labeled with Dil-acLDL and UEA-1. The 92% and 91% of them were positive for von Willebrand factor and endothelial nitric oxide synthase, respectively. Compared with the control, there were significantly fewer adhering endothelial progenitor cells in chronic obstructive pulmonary disease patients: 18.7 ± 4.8/field vs. 45.0 ± 5.9/field, P < 0.05. The proliferation assay showed that the proliferative capacity of circulating endothelial progenitor cells from chronic obstructive pulmonary disease patients was significantly impaired: 0.135 ± 0.038 vs. 0.224 ± 0.042, P < 0.05. Furthermore, nitric oxide synthase (112.06 ± 10.00 vs. 135.41 ± 5.38, P < 0.05), phosphorylated endothelial nitric oxide synthase protein expression (88.89 ± 4.98 vs. 117.98 ± 16.49, P < 0.05) and nitric oxide production ((25.11 ± 5.27) µmol/L vs. (37.72 ± 7.10) µmol/L, P < 0.05) were remarkably lower in endothelial cells from the chronic obstructive pulmonary disease group than the control.</p><p><b>CONCLUSION</b>Circulating endothelial progenitor cells were decreased and functionally impaired in patients with chronic obstructive pulmonary disease.</p>


Asunto(s)
Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Antígeno AC133 , Antígenos CD , Metabolismo , Antígenos CD34 , Metabolismo , Células Endoteliales , Metabolismo , Patología , Glicoproteínas , Metabolismo , Péptidos , Metabolismo , Enfermedad Pulmonar Obstructiva Crónica , Metabolismo , Patología , Células Madre , Metabolismo , Patología , Receptor 2 de Factores de Crecimiento Endotelial Vascular , Metabolismo
14.
PLoS One ; 7(6): e38560, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22693647

RESUMEN

BACKGROUND: Abnormal posture and spinal mobility have been demonstrated to cause functional impairment in the quality of life, especially in the postmenopausal osteoporotic population. Most of the literature studies focus on either thoracic kyphosis or lumbar lordosis, but not on the change of the entire spinal alignment. Very few articles reported the spinal alignment of Chinese people. The purpose of this study was threefold: to classify the spinal curvature based on the classification system defined by Satoh consisting of the entire spine alignment; to identify the change of trunk mobility; and to relate spinal curvature to balance disorder in a Chinese population. METHODOLOGY/PRINCIPAL FINDINGS: 450 osteoporotic volunteers were recruited for this study. Spinal range of motion and global curvature were evaluated noninvasively using the Spinal-Mouse® system and sagittal postural deformities were characterized. RESULTS: We found a new spine postural alignment consisting of an increased thoracic kyphosis and decreased lumbar lordosis which we classified as our modified round back. We did not find any of Satoh's type 5 classification in our population. Type 2 sagittal alignment was the most common spinal deformity (38.44%). In standing, thoracic kyphosis angles in types 2 (58.34°) and 3 (58.03°) were the largest and lumbar lordosis angles in types 4 (13.95°) and 5 (-8.61°) were the smallest. The range of flexion (ROF) and range of flexion-extension (ROFE) of types 2 and 3 were usually greater than types 4 and 5, with type 1 being the largest. CONCLUSIONS/SIGNIFICANCE: The present study classified and compared for the first time the mobility, curvature and balance in a Chinese population based on the entire spine alignment and found types 4 and 5 to present the worst balance and mobility. This study included a new spine postural alignment classification that should be considered in future population studies.


Asunto(s)
Osteoporosis/fisiopatología , Anciano , Anciano de 80 o más Años , Estudios Transversales , Femenino , Humanos , Vértebras Lumbares/fisiopatología , Persona de Mediana Edad , Rango del Movimiento Articular , Curvaturas de la Columna Vertebral/fisiopatología
15.
Zhongguo Gu Shang ; 24(8): 667-71, 2011 Aug.
Artículo en Chino | MEDLINE | ID: mdl-21928674

RESUMEN

OBJECTIVE: To investigate the therapeutic effects of closed reduction and external fixation (plaster or splint) for the treatment of displaced humeral supracondylar fractures in children. METHODS: From March 2007 to September 2009,33 children (15 female and 18 male) with humeral supracondylar fractures treated in our hospital, ranging from 3 to 12 years old with an average of 6.4 years old. All the fractures were extension-type injuries, the flexion injures were excluded in our study. The humeral supracondylar fractures were classified according to Gartland classification. There were 21 Type H and 12 type III. In the initial treatment, all the patients were treated with closed reduction and external immobilization. The blood supply of the damaged upper extremity was evaluated before and after treatment. Clinical assessment was obtained at final follow-up using Flynn criteria, and radiologic assessment was obtained using Baumann and lateral humerocapitellar angles. RESULTS: All the children were treated successfully with closed reduction in the initial time; 24 children maintained limb alignment by external immobilization. Nine patients lost position due to the swelling around the elbow which affected unstable external fixation during the follow-up, 5 of which were treated with a repeated closed reduction and internal fixation with Kirschner wires, 4 of which were treated with traction. Thirty-one patients had a satisfactory outcome and 2 patients had an unsatisfactory outcome according to the Flynn criteria at the latest follows-up. CONCLUSION: Closed reduction and external stabilization is an important method for the treatment of displaced humeral supracondylar fractures in children. Making regular follow-up visits after closed reduction and casting is important for patients to maintain acceptable alignment, avoid complications and diagnose any loss of reduction.


Asunto(s)
Moldes Quirúrgicos , Fijadores Externos , Fracturas del Húmero/cirugía , Férulas (Fijadores) , Niño , Preescolar , Femenino , Fijación Interna de Fracturas , Humanos , Masculino
16.
Chinese Journal of Epidemiology ; (12): 274-278, 2011.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-295943

RESUMEN

Objective To study the spatiotemporal trend of Japanese encephalitis in Guangxi Zhuang Autonomous Region between 1989 and 2006.Methods Retrospective space-time permutation scan statistic and inverse distance weighted (IDW) interpolation were employed to detect the spatiotemporal trend of Japanese encephalitis in Guangxi,from the year 1989 to 2006.Results The spatiotemporal pattern of Japanese encephalitis was divided into four phases by IDW interpolation maps,from 1989 to 2006.The first phase was spatiotemporal cluster located in southeast region,from 1989 to 1996.The second phase showed discrete distribution from 1997 to 1998.The third phase of spatiotemporal cluster located in Lingshan county,Pubei county and Bobai county,in 1999.And the last phase was spatiotemporal cluster located in northwest region from 2000 to 2006.Three statistically significant spatiotemporal clusters were detected by retrospective space-time permutation scan statistic.The primary cluster appeared in 1999 (LLR=253.25,P=0.001,RR=4.62),with 109°54′ E,22°28′ N (located in Pubei county) as its center and radiated 45.24 km.From 2000 to 2006,the secondary cluster showed in northwest (LLR=75.91,P=0.001,RR = 1.88),with center located at 105°23′ E,24°68′ N (Longlin county),and radiated 199.85 kn.From 1989 to 1996,the other secondary cluster appeared in the southeast area(LLR=46.29,P=0.001,RR= 1.16),with center located at 110°94′ E,24°03′N(Zhaoping county) and radiated 229.12 km.Conclusion Space-time permutation scan statistic and geographical information system could be applied to quantitatively detect the potentially spatiotemporal trend of the disease.The spatiotemporal cluster shifted from southeast to northwest,from 1989 to 2006.

17.
Int J Epidemiol ; 38(3): 698-705, 2009 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-18250076

RESUMEN

BACKGROUND: Prenatal exposure to smoking has been associated with Attention Deficit Hyperactivity Disorder (ADHD) in a number of epidemiological studies. However, mothers with the ADHD phenotype may 'treat' their problem by smoking and therefore be more likely to smoke even in a society where smoking is not acceptable. This will cause genetic confounding if ADHD has a heritable component, especially in populations with low prevalence rates of smoking since this reason for smoking is expected to be proportionally more frequent in a population with few 'normal' smokers. We compared the association in cohorts with different smoking frequencies. METHODS: A total of 20 936 women with singleton pregnancies were identified within three population-based pregnancy cohorts in Northern Finland (1985-1986) and in Denmark (1984-1987 and 1989-1991). We collected self-reported data on their pre-pregnancy and pregnancy smoking habits and followed the children to school age where teachers and parents rated hyperactivity and inattention symptoms. RESULTS: Children, whose mothers smoked during pregnancy, had an increased prevalence of a high hyperactivity-inattention score compared with children of nonsmokers in each of the cohorts after adjustment for confounders but we found no statistical significant difference between the associations across the cohorts. CONCLUSION: The estimated association was not strongest in the population with the fewest smokers which does not support the hypothesis that the association is entirely due to genetic confounding.


Asunto(s)
Trastorno por Déficit de Atención con Hiperactividad/epidemiología , Hipercinesia/epidemiología , Efectos Tardíos de la Exposición Prenatal/epidemiología , Fumar/efectos adversos , Adolescente , Trastorno por Déficit de Atención con Hiperactividad/genética , Actitud Frente a la Salud , Niño , Factores de Confusión Epidemiológicos , Dinamarca/epidemiología , Femenino , Finlandia/epidemiología , Humanos , Hipercinesia/genética , Masculino , Madres , Embarazo , Efectos Tardíos de la Exposición Prenatal/genética , Prevalencia , Fumar/epidemiología , Fumar/genética , Encuestas y Cuestionarios
18.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-814241

RESUMEN

OBJECTIVE@#To determine the effect of atorvastatin on lipopolysaccharide-induced expression of C-reactive protein in cultured A549 cells.@*METHODS@#A549 cells were incubated in DMEM medium containing lipopolysaccharide in the absence or presence of various concentrations of atorvastatin. After the incubation, the medium was collected and the level of C-reactive protein was measured by enzyme-linked immunosorbent assay. The cells were harvested and C-reactive protein mRNA was analyzed by reverse transcription polymerase chain reaction.@*RESULTS@#Incubation with lipopolysaccharide significantly induced a time and dose dependent increase in the mRNA expression and the production of C-reactive protein in A549 cells (P<0.05). Atorvastatin significantly decreased the lipopolysaccharide induced the mRNA expression and the production of C-reactive protein in a dose dependent manner in A549 cells (P<0.05).@*CONCLUSION@#Atorvastatin downregulates lipopolysaccharide-induced expression of C-reactive protein in cultured A549 cells, which may be its mechanism of anti-inflammation.


Asunto(s)
Humanos , Atorvastatina , Proteína C-Reactiva , Genética , Metabolismo , Línea Celular , Regulación hacia Abajo , Células Epiteliales , Metabolismo , Patología , Ácidos Heptanoicos , Farmacología , Lipopolisacáridos , Pulmón , Metabolismo , Patología , Pirroles , Farmacología , ARN Mensajero , Genética , Metabolismo
19.
Artículo en Chino | MEDLINE | ID: mdl-14663946

RESUMEN

OBJECTIVE: To investigate the therapeutic effect of flap transplantation in repairing soft tissue defects of children. METHODS: From January 1997 to May 2002, 75 cases of different soft tissue defects (52 males and 23 females, with the age of 3-14 years) were repaired by axial and non-axial flaps transfer, and axial flaps transplantation by microvascular anastomosis. The flaps area ranged from 3 cm x 5 cm to 15 cm x 42 cm. Emergency operation was performed in 26 cases and secondary operation in 49 cases (infective wound such as osteomyelitis and plate extra-exposed of fracture). The defect regions included the forearm, back of the hand, thumb, index finger, leg and foot. The types of flap graft and application range included 39 cases of axial flaps transfer or transplantation (27 cases of along- or contra-transfer of transplantation and 12 cases of microvascular anastomosis). The non-axial flaps transfer were designed along- or contra-transfer near the wound area in 36 cases. The ratio of length to width was 2.5:1-3.5:1 in 27 cases, and larger than 3.5:1 in 9 cases. Adequate anesthesia method should be chosen according to the characteristics of children, non-traumatic operating during surgery and postoperative supervision and nursing of flaps should also be paid enough attention. RESULTS: After operation, blood circulation crisis occurred in 2 cases (1 case of artery failure and 1 case of vein failure). The flaps survived in 37 cases and partially survived in 1 case and necrosed in 1 case. The survival rate was 96.2%. The postoperative follow-up period was 3 to 60 months, the blood supply, elasticity and texture of flaps were good. The effect of repair was satisfactory. CONCLUSION: Different types of transplantation of blood-supply of flaps may repair the different types of soft tissue defects in children. Free flap transplantation is safe and beneficial in children, different defects of soft tissue were repaired by axial and non-axial flaps transfer, axial flaps transplantation by microvascular anastomosis. Non-traumatic operating and postoperative supervision and nursing of flaps should also be paid enough attention.


Asunto(s)
Traumatismos de la Mano/cirugía , Osteomielitis/cirugía , Traumatismos de los Tejidos Blandos/cirugía , Colgajos Quirúrgicos , Adolescente , Traumatismos del Brazo/cirugía , Niño , Preescolar , Femenino , Estudios de Seguimiento , Supervivencia de Injerto , Humanos , Traumatismos de la Pierna/cirugía , Masculino , Osteomielitis/complicaciones , Procedimientos de Cirugía Plástica , Estudios Retrospectivos , Traumatismos de los Tejidos Blandos/complicaciones
20.
Di Yi Jun Yi Da Xue Xue Bao ; 23(9): 983-5, 2003 Sep.
Artículo en Chino | MEDLINE | ID: mdl-13129744

RESUMEN

OBJECTIVE: To retrospectively analyze the surgical repair of injured major vessels in the extremities complicated by multiple other injuries. METHODS: According to different time lengths of sustaining ischemia, sites of the major vascular injuries and conditions of other injuries, 91 operations for end-to-end anastomosis, vessel grafting and repair, ligation and shunting respectively were performed on the 67 patients. RESULTS: Except for 2 fatal cases (one due to preoperative brain hernia and hemorrhagic shock, the other to thyroid crisis during operation), all other cases survived the operations. Vascular crisis occurred in 3 cases (2 arterial spasm and 1 venous crisis) 6, 7 and 12 h respectively after the operations, which were relieved by appropriate treatments and surgical explorations. One patient developed pneumonia and acute renal failure with polyuria at postoperative days 7 and 4 respectively, but full recovery was achieved. CONCLUSIONS: For patients with major vascular injuries in the extremity complicated by multiple other injuries, timely revascularization of the extremities should be performed during or immediately after emergency operations of the vital organs. Particular attention should be given to the diagnosis and repair of closed major vascular injuries in such patients, who need to be monitored for blood coagulation during operation and should receive due post-operative anti-coagulation treatment.


Asunto(s)
Vasos Sanguíneos/lesiones , Extremidades/irrigación sanguínea , Extremidades/lesiones , Procedimientos Quirúrgicos Vasculares/métodos , Adolescente , Adulto , Anciano , Niño , Preescolar , Femenino , Humanos , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias/prevención & control , Estudios Retrospectivos , Procedimientos Quirúrgicos Vasculares/efectos adversos
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