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1.
FEBS Open Bio ; 2020 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-32602250

RESUMO

Niclosamide is a potent inhibitor of osteoclastogenesis and bone remodeling. DK-520 is an acyl derivative of Niclosamide and significantly increased both the plasma concentration and the duration of exposure of Niclosamide when dosed orally.However, at present the effect of DK-520 on osteoclastogenesis has not been reported. Here, we investigated whether DK-520 can regulate receptor activator of nuclear factor-κB ligand (RANKL)-induced osteoclastogenesis of bone marrow macrophages (BMMs) in vitro. Following induction of BMMs with RANKL for three days, we detected differentiated osteoclasts with typical morphology and high levels of tartrate resistant acid phosphatase (TRAP), RANKL, and Cathepsin K (CTSK) expression. Treatment with either Niclosamide or DK-520 did not affect the viability of osteoclast precursors (OCPs), but significantly inhibited RANKL-induced trans-differentiation of macrophages into OCPs, particularly in the early stage of osteoclastogenesis. Both Niclosamide and DK-520 significantly decreased the relative levels of transcription factor PU.1 mRNA transcripts and dendritic cell specific transmembrane protein (DC-STAMP), but not v-ATPasev0 d2 protein expression in OCPs. In addition, the inhibitory effect of DK-520 on osteoclastogenesis is realized through impairment of the NF-kB (nuclear factor-κB) and MAPK (mitogen activate protein kinase) signaling pathways. These results demonstrate that DK-520, like Niclosamide, effectively inhibits the early stage of osteoclastogenesis. The findings presented here, together with its increased oral plasma concentrations and bioavailability suggest that DK-520 may be a promising drug candidate for treatment of osteoclast-related diseases.

2.
Dermatol Ther ; : e13741, 2020 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-32478968

RESUMO

Androgenetic alopecia (AGA) is the most common type of baldness affecting both men and women. Studies investigating combination therapies for AGA reported greater efficacy than monotherapy but without rigorous examination. The authors performed a meta-analysis and systemic review to further verify the evidence. To evaluate the effectiveness of three common combination therapies of minoxidil with finasteride, low-level laser light therapy (LLLT) or microneedling versus minoxidil monotherapy. We conducted a systematic review of randomized controlled trials (RCTs) of combination therapies consisting of topical minoxidil for AGA through April 2020. Quality assessment and data analysis were performed by Review Manager 5.3. Fifteen studies met the inclusion criteria involving a total of 1172 AGA patients. We conducted meta-analysis for three groups of combined treatment separately, and all were superior to monotherapy in terms of global photographic assessment (P < .05). Combination of LLLT or microneedling with minoxidil also showed significant increase in hair count (P < .05) compared to monotherapy. The present study suggests that combination therapy could be an effective, safe and promising option for the treatment of AGA. However, more RCTs are needed to further investigate and confirm the efficacy of combined treatment.

3.
Medicine (Baltimore) ; 99(22): e20406, 2020 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-32481432

RESUMO

BACKGROUND: Structural and functional changes in subchondral bone have been recognized as a key factor in the development of related disease, and subchondral bone may be a new target for the treatment of osteoarthritis. The purpose of our present study is to investigate the global status and trends of subchondral bone research. METHOD: Publications related to the studies of subchondral bone from 1993 to 2018 were retrieved from the Science Citation Index-Expanded Web of Science database. The data source was studied and indexed by using bibliometric methodology. For visualized study, bibliographic coupling analysis, co-authorship analysis, co-citation analysis, co-occurrence analysis and the analysis of publication trends in subchondral bone research were conducted by VOS viewer and GraphPadPrism 5 software. RESULTS: A total of 4780 publications were included. There is an increasing trend of the relative research interests and number of publications per year globally. The cumulative number of publications about subchondral bone research followed the logistic growth model (Equation is included in full-text article.). The USA made the highest contributions to the global research with the most citations, the highest H-index, and the most total link strength, while Denmark had the highest average citation per item. The journal Osteoarthritis and Cartilage had the largest publication number. Boston University is the most contributive institution. Studies could be divided into 4 clusters: "Mechanism research", "Animal study", "Clinical study" and "Pathological features". Less efforts were put into clinical study. CONCLUSION: The number of publications about subchondral bone research would be increasing in the next years based on the current global trends. Attention should be drawn to the latest popular research, including "Mesenchymal stem-cells", "Autologous chondrocyte implantation", "Microfracture" and "Pain". Therefore, more and more efforts will be put into mechanism research on subchondral bone, which may inspire new clinical treatments for osteoarthritis and other related diseases based on subchondral bone.

4.
Clin Genitourin Cancer ; 17(5): 319-331, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31371223

RESUMO

The treatment of renal cell carcinoma has achieved certain curative effects with the innovation of clinical drugs, such as sunitinib. However, the clinical efficacy and complication rate of the sunitinib 2/1 and 4/2 schedule in metastatic renal cell cancer remain unclear. In this study we aimed to resolve this issue by using meta-analysis to provide more theoretical guidance for clinical use. Several outcome measurements were included in this study to compare the 2 schedules such as complete response, partial response, stable disease, progressive disease, progression-free survival, overall survival, and complications. In the contrast analysis, the sunitinib 2/1 and 4/2 schedule resulted in significant improvements in prognosis. However, the sunitinib 2/1 schedule was superior to the 4/2 schedule in terms of controlling stable disease and causing fewer complications.

5.
Anal Chim Acta ; 1073: 22-29, 2019 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-31146832

RESUMO

An electrochemical sensor based on a glassy carbon electrode (GCE) modified by three-dimensional graphene (3D-GE) and polyglutamic acid (PGA) was developed to quantitatively detect Amoxicillin (AMX), a worldwide used antibiotic. AMX response at PGA/3D-GE/GCE involving the transfer of one electron and an equal number of protons were determined using electrochemical approaches. Density functional theory simulations were performed to give insights on the reaction mechanism of AMX on the surface of the modified electrode. When the optimization of the experimental conditions was completed, the linear range of AMX was 2-60 µM. Besides, the detection limit was calculated as 0.118 µM (S/N = 3). And the modified electrode could detect the concentration of the AMX in human urine samples. Overall, the developed PGA/3D-GE/GCE for determination of AMX shows great potentials in practice.


Assuntos
Amoxicilina/química , Teoria da Densidade Funcional , Grafite/química , Simulação de Dinâmica Molecular , Ácido Poliglutâmico/química , Técnicas Eletroquímicas , Eletrodos , Tamanho da Partícula , Propriedades de Superfície
6.
FEBS Lett ; 593(10): 1089-1101, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30977909

RESUMO

miR-134 has been shown to be associated with angiogenesis and the progression of osteosarcoma. This study further assessed the effects of miR-134 expression on osteosarcoma cell migration, invasion, and metastasis in vitro and in a nude mouse xenograft model, exploring the underlying molecular events. Luciferase reporter assays revealed that miR-134 directly targets the 3'-UTRs of MMP1 and MMP3 to reduce their expression in osteosarcoma cells. In conclusion, overexpression of miR-134 suppresses osteosarcoma cell invasion and metastasis through the inhibition of MMP1 and MMP3 expression. We propose miR-134 as an attractive novel therapeutic target for the treatment of osteosarcoma.

7.
Int J Med Robot ; 15(3): e1990, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30746868

RESUMO

BACKGROUND: Several studies have compared robotics-assisted (RA) and conventional manual (CM) approaches for total hip arthroplasty (THA), but their results are controversial. METHODS: A literature search was conducted for controlled clinical trials (CCTs) comparing the clinical efficacy of the RA and CM approaches for THA and published between August 1998 and August 2018. The obtained data were analyzed using the statistical software Review Manager 5.3. RESULTS: Fourteen articles were included in the meta-analysis, which revealed that the RA group had less intraoperative complications, better cup angle, and more cases of cup placement in the safe zone than the CM group. However, the operation time required for the CM group was less than that required for the RA group. Moreover, postoperative complications (eg, dislocation and revision surgery) were less frequent in the CM group than in the RA group. However, the two groups had similar functional scores, total number of complications, and rate of occurrence of limb length discrepancy. CONCLUSION: Compared with the CM approach, the RA approach yields better radiological outcomes and fewer intraoperative complications in THA, but similar functional scores.


Assuntos
Artroplastia de Quadril/métodos , Procedimentos Cirúrgicos Robóticos , Acetábulo/cirurgia , Ensaios Clínicos como Assunto , Articulação do Quadril/cirurgia , Prótese de Quadril , Humanos , Complicações Pós-Operatórias , Reoperação , Cirurgia Assistida por Computador
8.
J Int Med Res ; 47(2): 505-514, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30616454

RESUMO

OBJECTIVE: This study was performed to compare the clinical efficacy between the OrthoPilot navigation system and conventional manual surgery in patients undergoing total hip arthroplasty. METHODS: The Embase, PubMed, CINAHL, and Cochrane databases were searched for clinical trials. The outcome measurements were the anteversion angle, inclination angle, and complications. Review Manager 5.3 statistical software was used for the data analysis. RESULTS: Significant differences were found in the femoral offset and overall complication rate between the conventional and navigation groups. Additionally, the conventional group had significantly less anteversion than the navigation group. However, the navigation group had significantly better inclination. The operation time was significantly shorter in the conventional than navigation group. CONCLUSION: Both the OrthoPilot navigation system and conventional total hip arthroplasty result in significant improvements in patient function with similar overall complication rates and have their own advantages in achieving good cup position. The conventional procedure has a shorter operation time than does use of a navigation system.


Assuntos
Artroplastia de Quadril/instrumentação , Artroplastia de Quadril/métodos , Complicações Pós-Operatórias , Cirurgia Assistida por Computador/métodos , Humanos , Resultado do Tratamento
9.
Spectrochim Acta A Mol Biomol Spectrosc ; 212: 300-307, 2019 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-30660062

RESUMO

A novel fluorescent sensor based on g-C3N4 nanofibers for the sensitive detection of dopamine (DA) has been proposed. We synthesized g-C3N4 nanofibers by directly hydrolyzing bulk g-C3N4 in the alkaline atmosphere (3 M NaOH). The obtained ultrathin g-C3N4 nanofibers were verified by characterizations of Transmission electronic microscope (TEM), X-ray diffractometer (XRD), Fourier transformation-infrared (FT-IR) and X-ray photoelectron spectroscopy (XPS). It was found that the fluorescence intensity of g-C3N4 nanofibers was obviously quenched by DA. Fluorescence resonance energy transfer (FRET) between DA and g-C3N4 nanofibers led to the fluorescence reduction of g-C3N4 nanofibers. The fluorescent probe based on g-C3N4 nanofibers exhibits linear responses to the concentration of DA in the range from 0 to 4 µM and 4 to 20 µM, the limit of detection is 17 nM. The fluorescent probe shows excellent stability, good selectivity with its application in serums.


Assuntos
Dopamina/análise , Corantes Fluorescentes/química , Grafite/química , Nanofibras/química , Compostos de Nitrogênio/química , Espectrometria de Fluorescência/métodos , Dopamina/sangue , Humanos , Concentração de Íons de Hidrogênio , Nanofibras/ultraestrutura , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X
10.
Gene ; 680: 34-42, 2019 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-30218748

RESUMO

BACKGROUND: The influence of 5-HTT, BMPR2, EDN1, ENG, KCNA5 genes polymorphisms on susceptibility of pulmonary arterial hypertension remains uncertain. This meta-analysis is conducted for further study. METHODS: We conducted a literature search on PubMed and ISI web of science databases for searching relevant articles until November 2017. Pooled odds ratios (ORs) with 95% confidence intervals (CIs) were calculated. A total of 17 articles with 2631 PAH subjects and 5139 controls were included in the final meta-analysis. Statistical software Stata13.0 was used for data-analysis. RESULTS: A significant relationship was found between the 5-HTT L/S polymorphism and PAH in all the genetic models [LL vs. SS: OR = 1.60, 95% CI, 1.11-2.32; LS vs. SS: OR = 1.55, 95% CI, 1.10-2.21; (LS + LL) vs. SS: OR = 1.56, 95% CI, 1.13-2.17; L vs. S: OR = 1.32, 95% CI, 1.08-1.62]. There were also associations of the SERT L/S polymorphism with IPAH and PAH in COPD [IPAH L/S: OR = 1.26, 95% CI, 1.01-1.57; PAH in COPD L/S: OR = 1.42, 95% CI, 1.04-1.94]. In addition, the results showed a statistically significant association between EDN1 rs5370 polymorphism and the risk of PAH in all the genetic models [TT vs. GG: OR = 3.32, 95% CI, 1.30-8.51; TG vs. GG: OR = 2.68, 95% CI, 1.54-4.66; (TG + TT) vs. GG: OR = 2.82, 95% CI, 1.69-4.71; T vs. G: OR = 2.43, 95% CI, 1.60-3.68]. However, the significant association was not found between BMPR2 rs1061157, KCNA5 rs10744676, ENG rs3739817 polymorphisms and the risk of PAH (all p > 0.05). CONCLUSIONS: 5-HTT L/S polymorphism and END1 rs5370 polymorphism were correlated with significantly increased risk of PAH. Moreover, L allele in 5-HTT gene increased susceptibility to IPAH and PAH in COPD.


Assuntos
Redes Reguladoras de Genes , Estudos de Associação Genética/métodos , Hipertensão Pulmonar/genética , Polimorfismo de Nucleotídeo Único , Adulto , Idoso , Receptores de Proteínas Morfogenéticas Ósseas Tipo II/genética , Endoglina/genética , Endotelina-1/genética , Predisposição Genética para Doença , Humanos , Canal de Potássio Kv1.5/genética , Pessoa de Meia-Idade , Proteínas da Membrana Plasmática de Transporte de Serotonina/genética , Adulto Jovem
11.
FEBS J ; 285(7): 1359-1371, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29474747

RESUMO

Vascular endothelial growth factor (VEGF) A and vascular endothelial growth factor receptor 1 (VEGFR1) signaling is crucial for angiogenesis and progression of osteosarcoma (OS). However, the regulation of the VEGF/VEGFR1 expression is still unclear in OS. Here, we show lower levels of miRNA-134 (miR-134) in OS tissues and cells. Induction of miR-134 overexpression significantly reduced the proliferation of Saos-2 cells and their secretion of pro-angiogenic factors, but increased the frequency of apoptotic Saos-2 cells. Treatment with conditioned medium from the cells transfected with miR-134 reduced the tube formation in human umbilical vein endothelial cells, which was abrogated by a combination of VEGF and conditioned medium. Furthermore, miR-134 significantly inhibited the growth of implanted OS tumors in vivo and attenuated the VEGFA and VEGFR1 expression and angiogenesis in the tumors. In addition, higher levels of VEGFA and VEGFR1 were detected and miR-134 inhibited the expression of VEGFA and VEGFR1 in Saos-2 cells and OS tumors. Bioinformatic analysis indicated that the 3'-UTR of VEGFA and VEGFR1 contained the motif for miR-134 binding. Co-transfection with the luciferase reporter containing the wild-type, but not the mutant, of the 3'-UTR of VEGFA or VEGFR1 together with miR-134 decreased the luciferase activity in Saos-2 cells. Finally, miR-134 dramatically inhibited AKT activation and proliferating cell nuclear antigen expression in Saos-2 cells. Collectively, these findings indicate that miR-134 is a potential tumor suppressor by targeting VEGFA/VEGFR1 signaling to attenuate the progression and angiogenesis in OS. Therefore, miR-134 may be a novel biomarker for the prognosis of OS and a target for the design of new therapies for OS.


Assuntos
Sistemas de Liberação de Medicamentos , MicroRNAs/genética , MicroRNAs/metabolismo , Osteossarcoma/fisiopatologia , Transdução de Sinais , Fator A de Crescimento do Endotélio Vascular/genética , Linhagem Celular , Proliferação de Células/genética , Expressão Gênica , Humanos , Osteossarcoma/genética , Transdução de Sinais/genética
12.
IEEE Trans Image Process ; 26(6): 2811-2824, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28320664

RESUMO

Geometric transformations, such as resizing and rotation, are almost always needed when two or more images are spliced together to create convincing image forgeries. In recent years, researchers have developed many digital forensic techniques to identify these operations. Most previous works in this area focus on the analysis of images that have undergone single geometric transformations, e.g., resizing or rotation. In several recent works, researchers have addressed yet another practical and realistic situation: successive geometric transformations, e.g., repeated resizing, resizing-rotation, rotation-resizing, and repeated rotation. We will also concentrate on this topic in this paper. Specifically, we present an in-depth analysis in the frequency domain of the second-order statistics of the geometrically transformed images. We give an exact formulation of how the parameters of the first and second geometric transformations influence the appearance of periodic artifacts. The expected positions of characteristic resampling peaks are analytically derived. The theory developed here helps to address the gap left by previous works on this topic and is useful for image security and authentication, in particular, the forensics of geometric transformations in digital images. As an application of the developed theory, we present an effective method that allows one to distinguish between the aforementioned four different processing chains. The proposed method can further estimate all the geometric transformation parameters. This may provide useful clues for image forgery detection.

13.
Huan Jing Ke Xue ; 38(8): 3254-3263, 2017 Aug 08.
Artigo em Chinês | MEDLINE | ID: mdl-29964933

RESUMO

Long-term field monitoring data was analyzed regarding the characteristics of nitrogen and phosphorus in the soil and shallow groundwater of different land use types in a typical small watershed of the Three Gorges Reservoir area. Furthermore, the relationships among soil nitrogen and phosphorus contents, concentrations of nitrogen and phosphorus in shallow groundwater, and slope surface runoff were analyzed. The results showed that the average contents of TN and NO3--N in terrace soil were significantly higher than those in sloping upland soil (P< 0.05), for which the average content of paddy terrace was highest (1.49 g·kg-1). The average contents of TP in the soil of sloping upland and mulberry-sloping upland were significantly higher than those in the soil of other land types. The average content of NO3--N in the soil of dryland terrace was highest of all land use types and its discrete degree was also largest. The slope land use type had greater impact on the concentrations of TN and NO3--N in shallow groundwater, but it had little influence on TP concentration. In addition, the shallow groundwater TN concentration and NO3--N concentration had significant positive correlation, and the average contribution rate of NO3--N to TN in five wells ranged from 67.82% to 78.51%. The monthly average concentration of TN and NO3--N in shallow groundwater changed little, only showing a significant upward trend after the fertilization stage of the two crops in spring and autumn. The average contents of TN and NO3--N in the slope soil were significantly correlated with the TN and NO3--N concentrations in the shallow groundwater, but there was no significant correlation between the TN and NO3--N concentrations in the surface runoff. When the slope surface runoff TP concentration was>0.1 mg·L-1, the average content of TP had a significant linear correlation with it. There was a significant power function relationship between the concentrations of TN and NO3--N in the surface runoff and concentrations of TN and NO3--N in the shallow groundwater, with higher correlation of NO3--N concentrations between surface runoff and shallow groundwater.

14.
Huan Jing Ke Xue ; 38(5): 1889-1897, 2017 May 08.
Artigo em Chinês | MEDLINE | ID: mdl-29965093

RESUMO

This paper used three plots of paddy field in Wangjiagou small catchment in Fuling District, Chongqing Municipality as a case study. Wangjiagou, located in Three Gorges Reservoir Area, provided a good case in terms of its closeness of surface runoff. The samples of individual rainfall of twelve times and process of two typical individual rainfalls on three plots of sloping paddy field were collected from 2014 to 2015. These samples were used to analyze the influence of spatial pattern of sloping paddy field on the concentration of nitrogen and phosphorus in the surface runoff. The samples of daily runoff in subcatchments in 2010 and 2015 were used to analyze the influence of spatial pattern change of subcatchments' paddy field on the concentration of nitrogen and phosphorus in the surface runoff. The results indicated that the removal rates of TN, NO3--N and TP of paddy field at the valley bottom were higher than those in the mid-slopes. The removal rate of TP would be higher if plot size of paddy field at the bottom got bigger. During individual rainfall event, the losses concentration of TN, NO3--N and TP in the paddy fields was significantly different among three different spatial patterns during the previous period of heavy rain event, but it became different during the next period of moderate rain event. The two subcatchments' spatial pattern change of paddy field had weakened the intercepting purification ability of nitrogen and phosphorus losses of paddy field in 2015, compared with that in 2010. TN's losses concentration increased significantly during the periods of light and moderate rain event and base flow. TP's losses concentration fluctuated during the event from moderate rain to heavy rain. Hence, increasing the area of paddy field of catchment and optimizing its spatial pattern reasonably were found as effective measures to control agricultural non-point source pollution in the Three Gorges Reservoir Region.


Assuntos
Monitoramento Ambiental , Nitrogênio/análise , Fósforo/análise , Movimentos da Água , Poluentes Químicos da Água/análise , Agricultura , China , Cidades , Oryza , Chuva , Análise Espacial
15.
Huan Jing Ke Xue ; 37(5): 1707-16, 2016 May 15.
Artigo em Chinês | MEDLINE | ID: mdl-27506023

RESUMO

As an independent water-collecting area, small catchment is the source of non-point source pollution in Three Gorges Region. Choosing 3 kinds of the most representative land-use types and using them to lay monitoring points of overland runoff within the small catchment of Wangjiagou in Fuling of Three Gorges Region, the author used the samples of surface runoff collected through the twelve natural rainfalls from May to December to analyze the feature of spatial-temporal change of Nitrogen's losses concentrations under the influence of different land use types and the hillslopes and small catchments composed by those land use types, revealing the relation between different land-use types and Nitrogen's losses of small catchments in Three Gorges Region. The result showed: the average losses concentration of TN showed the biggest difference for different land use types during the period of spring crops, and the average value of dry land was 1. 61 times and 6.73 times of the values of interplanting field of mulberry and paddy field, respectively; the change of the losses concentration of TN was most conspicuous in the 3 periods of paddy field. The main element was NO3⁻-N, and the relation between TN and NO3⁻-N showed a significant linear correlation. TN's and NO3⁻-N's losses concentrations were significantly and positively correlated with the area ratio of corn and mustard, but got a significant negative correlation with the area ratio of paddy and mulberry; NH4⁺-N's losses concentrations got a significant positive correlation with the area ratio of mustard. Among all the hillslopes composed by different land use types, TN's average losses concentration of surface runoff of the hillslope composed by interplantating field of mulberry and paddy land during the three periods was the lowest, and the values were 2.55, 11.52, 8.58 mg · L⁻¹, respectively; the hillslope of rotation plough land of corn and mustard had the maximum value, and the values were 27.51, 25.11, 27.11 mg · L⁻¹, respectively; different land use types and spatial combination ways of subcatchment had a greater influence on TN's losses concentrations, so using a reasonable way to adjust land use structure and spatial arrangement of whole catchment was an effective measure to control the source of non-point source pollution of Three Gorges Region.


Assuntos
Monitoramento Ambiental , Nitrogênio/análise , Movimentos da Água , Poluentes Químicos da Água/análise , Água/química , Agricultura , China , Produtos Agrícolas , Fósforo
16.
Environ Monit Assess ; 188(4): 257, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27358999

RESUMO

Losses of agricultural pollutants from small catchments are a major issue for water quality in the Three Gorges Region. Solutions are urgently needed. However, before pollutant losses can be controlled, information about spatial and temporal variations in pollutant losses is needed. The study was carried out in the Wangjiagou catchment, a small agricultural catchment in Fuling District, Chongqing, and the data about non-point source losses of nitrogen and phosphorus was collected here. Water samples were collected daily by an automatic water sampler at the outlets of two subcatchments from 2012 to 2014. Also, samples of surface runoff from 28 sampling sites distributed through the subcatchments were collected during 12 rainfall events in 2014. A range of water quality variables were analyzed for all samples and were used to demonstrate the variation in non-point losses of nitrogen and phosphorus over a range of temporal and spatial scales and in different types of rainfall in the catchment. Results showed that there was a significant linear correlation between the mass concentrations of total nitrogen (TN) and nitrate (NO3-N) in surface runoff and that the relationship was maintained with changes in time. Concentrations of TN and NO3-N peaked after fertilizer was applied to crops in spring and autumn; concentrations decreased rapidly after the peak values in spring but declined slowly in autumn. N and P concentrations fluctuated more and showed a greater degree of dispersion during the spring crop cultivation period than those in autumn. Concentrations of TN and NO3-N in surface runoff were significantly and positively correlated with the proportion of the area that was planted with corn and mustard tubers, but were negatively correlated with the proportion of the area taken up with rice and mulberry plantations. The average concentrations of TN and NO3-N in surface runoff reached the highest level from the sampling points at the bottom of the land used for corn only, but lowest in rice fields. Slope gradient had a significant positive correlation with TN's and total phosphorus (TP)'s concentration losses. Concentrations of TN, NO3-N, and total phosphorus were significantly correlated with rainfall. Peak concentrations of ammoniacal nitrogen occurred during the fertilizer application period in spring and autumn. Different structures of land use types had a significant influence on the concentration losses of nitrogen and phosphorus; thus, using a reasonable way to adjust land use structure and spatial arrangement of whole catchment was an effective solution to control non-point source pollution of the Three Gorges Region.


Assuntos
Monitoramento Ambiental/métodos , Nitrogênio/análise , Fósforo/análise , Poluição Química da Água/estatística & dados numéricos , China , Análise Espaço-Temporal , Poluição Química da Água/análise
17.
Carbohydr Polym ; 121: 175-82, 2015 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-25659687

RESUMO

A sulfated polysaccharide, designated CP2-1, was isolated from the green alga Codium divaricatum by water extraction and purified by anion-exchange and size-exclusion chromatography. CP2-1 is a galactan which is highly sulfated and substituted with pyruvic acid ketals. On the basis of chemical and spectroscopic analyses, the backbone of CP2-1 was mainly composed of (1→3)-ß-d-galactopyranose residues, branched by single (1→)-ß-d-galactopyranose units attached to the main chain at C-4 positions. The degree of branching was estimated to be about 12.2%. Sulfate groups were at C-4 of (1→3)-ß-d-galactopyranose and C-6 of non-reducing terminal galactose residues. In addition, the ketals of pyruvic acid were found at 3,4- of non-reducing terminal galactose residues forming a five-membered ring. CP2-1 possessed a high anticoagulant activity as assessed by the activated partial thromboplastin time and thrombin time assays. The investigation demonstrated that CP2-1 was an anticoagulant-active sulfated polysaccharide distinguishing from other sulfated polysaccharides from marine green algae.


Assuntos
Anticoagulantes/química , Anticoagulantes/farmacologia , Clorófitas/química , Polissacarídeos/química , Polissacarídeos/farmacologia , Sulfatos/química , Sequência de Carboidratos , Humanos , Metilação , Dados de Sequência Molecular , Tempo de Tromboplastina Parcial , Tempo de Trombina , Água/química
18.
Carbohydr Polym ; 111: 485-91, 2014 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-25037379

RESUMO

A water soluble extracellular polysaccharide, designated GW-12, was obtained from the liquid culture broth of the mangrove fungus Penicillium solitum by ethanol precipitation, anion-exchange and size-exclusion chromatography. Reversed-phase high performance liquid chromatography analysis showed that GW-12 mainly consisted of d-mannose, and its molecular weight was estimated to be about 11.3 kDa determined by high performance gel permeation chromatography. On the basis of chemical and spectroscopic analyses, including methylation analysis and nuclear magnetic resonance (NMR) spectroscopy, the structure of GW-12 may be represented as a mannan with branches. The main chain of GW-12 was composed of (1 → 2)-linked α-D-mannopyranose and (1 → 6)-linked α-D-mannopyranose residues, branched by single α-d-mannopyranose units attached to the main chain at C-6 positions of (1 → 2)-linked α-D-mannopyranose residues. There was three branch points for every seven sugar residues in the backbone.


Assuntos
Mananas/química , Penicillium/química , Sequência de Carboidratos , Cromatografia em Gel , Mananas/isolamento & purificação , Manose/análise , Manose/isolamento & purificação , Metilação , Dados de Sequência Molecular , Ressonância Magnética Nuclear Biomolecular , Penicillium/isolamento & purificação , Polissacarídeos/química , Polissacarídeos/isolamento & purificação
19.
IEEE Trans Image Process ; 22(12): 4699-710, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23955753

RESUMO

Recently, the median filtering (MF) detector as a forensic tool for the recovery of images' processing history has attracted wide interest. This paper presents a novel method for the blind detection of MF in digital images. Following some strongly indicative analyses in the difference domain of images, we introduce two new feature sets that allow us to distinguish a median-filtered image from an untouched image or average-filtered one. The effectiveness of the proposed features is verified with evidence from exhaustive experiments on a large composite image database. Compared with prior arts, the proposed method achieves significant performance improvement in the case of low resolution and strong JPEG post-compression. In addition, it is demonstrated that our method is more robust against additive noise than other existing MF detectors. With analyses and extensive experimental researches presented in this paper, we hope that the proposed method will add a new tool to the arsenal of forensic analysts.


Assuntos
Segurança Computacional , Processamento de Imagem Assistida por Computador/métodos , Compressão de Dados , Bases de Dados Factuais , Ciências Forenses
20.
Zhonghua Wei Chang Wai Ke Za Zhi ; 16(4): 328-31, 2013 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-23608792

RESUMO

OBJECTIVE: To investigate the risk factors for anastomotic infectious complications after bowel resection in patients with Crohn disease. METHODS: Clinical data of 124 patients with Crohn disease undergoing bowel resection between January 1990 and October 2012 were analyzed retrospectively. The risk factors were identified by χ(2) test and Logistic regression. RESULTS: Fourteen patients (12.3%, 14/114) developed anastomotic infectious complications in the postoperative period, including anastomotic leak (n=7), intra-abdominal abscess (n=6), and enterocutaneous fistula (n=1). Crohn disease activity index (CDAI)>150 (OR=2.185, 95%CI:1.098-6.256, P=0.040), steroid usage (OR=2.674, 95%CI:1.118-8.786, P=0.027), and the presence of preoperative abscess/fistula (OR=3.447, 95%CI:1.254-10.462, P=0.014) were identified as independent risk factors of anastomotic infectious complications. In the absence of these 3 risk factors, the rate of anastomotic infectious complication was 5.7% (3/53), which increased to 11.4% (4/35) when one risk factor was present, 21.1% (4/19) when two risk factors were present, and 42.9% (3/7) when all the 3 risk factors were present. CONCLUSIONS: CDAI>150, steroid usage and preoperative abscess/fistula are associated with higher rates of anastomotic infectious complications following bowel resection for Crohn disease. A prudent management should be carried out if risk factors can not be eliminated preoperatively.


Assuntos
Colectomia/efeitos adversos , Infecção da Ferida Cirúrgica/etiologia , Abscesso Abdominal/patologia , Adolescente , Adulto , Idoso , Anastomose Cirúrgica/efeitos adversos , Fístula Anastomótica/patologia , Distribuição de Qui-Quadrado , Doença de Crohn/cirurgia , Feminino , Humanos , Fístula Intestinal/patologia , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco , Esteroides/uso terapêutico , Infecção da Ferida Cirúrgica/cirurgia , Adulto Jovem
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