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1.
Huan Jing Ke Xue ; 44(9): 4785-4798, 2023 Sep 08.
Artigo em Chinês | MEDLINE | ID: mdl-37699798

RESUMO

Based on 2005-2020 O3 column concentration data of OMI remote sensing satellite, combined with air pollutant data from 10 nationally controlled environmental automatic monitoring stations in the Hexi Corridor and global data assimilation system meteorological data, we used Kriging interpolation, correlation analysis, and backward trajectory (HYSPLIT) models to explore the temporal and spatial distribution characteristics, meteorological factors, transmission paths, and potential sources of O3 in the Hexi Corridor. The results showed the following:① in terms of temporal distribution, O3 column concentration showed an upward trend in 2005-2010 and 2014-2020 and downward trend in 2010-2014; the maximum and minimum values were reached in 2010 and 2014 (332.31 DU and 301.00 DU), respectively, and seasonal changes showed that those in spring and winter were significantly higher than those in summer and autumn. ② In terms of spatial distribution, O3 column concentration showed a latitudinal band distribution characteristic of increasing from southwest to northeast; the high-value areas were primarily distributed in urban areas with low terrain, and the median zone was latitudinally striped with the basic alignment of the Qilian foothills. ③ The analysis of meteorological conditions revealed that temperature, wind speed, and sunshine hours were positively correlated with O3, and relative humidity was negatively correlated with O3. ④ By simulating the airflow transportation trajectory of the receiving point in Wuwei City, it was found that the direction of the O3 conveying path was relatively singular; the dominant airflow in each season was primarily in the west and northwest; and the proportions were 71.62%, 66.85%, 61.22%, and 77.78%, respectively. There were certain seasonal differences in the source areas of O3 potential contribution:the high-value areas of O3 potential sources in spring, summer, and autumn were distributed in Baiyin City and Lanzhou City, which were southeast wind sources, and the high-value areas in winter were distributed between the Badain Jaran Desert and the Tengger Desert, which was the north wind source.

2.
Sci Total Environ ; 903: 166772, 2023 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-37666333

RESUMO

Recent climate change has been shown to alter aspects of forest plant demography, such as growth and mortality, but less attention has been focused on how climate change alters the reproduction of plant populations through time. We hypothesized that the plant seed production would respond to climate change, and that the response would differ according to plant life form and functional traits. We tested this hypothesis by examining climate change from 2005 to 2020 and by determining the temporal trends of seed rain and seed production from plants with different life forms (e.g., herbs, vines, trees, palms) and of tree species with different statures as well as leaf, seed and wood traits during 2014-2020. We also tested the correlation between meteorological variables and time series of seed rain using cross correlation analysis. We found increasing wetness (lower vapor pressure deficit) through time but with decreasing minimum relative humidity, which is a pattern consistent with trends seen in many other parts of the world. During the study period, seed production of shrubs and relative contribution of woody vines to total seed rain decreased, while relative contribution of palms to total seed rain and tree species with more conservative leaf traits increased their contribution to total seed rain. Overall, these trends were well explained by the trends of meteorological variables and the responses of these life forms to climate change in previous studies. Additionally, the increasingly conservative leaf traits were also consistent with shifts in traits following recovery from disturbance. Our results suggest that a trait-based approach may help to unveil trends that are not readily apparent by examining seed counts alone. The compositional change found in the seed rain may indicate future shifts in forest species composition and should be incorporated into future studies of forest modelling and projections under climate change.

3.
Mitochondrial DNA B Resour ; 8(8): 921-926, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37645477

RESUMO

Liupao tea is one of the well-known Chinese tea brands and a famous local specialty in Wuzhou, Guangxi, China. However, the genetic background and phylogenetic relationship of the native resource plants of Liupao tea need study, especially at the genomic level. In this study, we reported the complete chloroplast (cp) genome sequence of Camellia sinensis var. sinensis cultivar 'Liupao' (LP, Liupao tea population) and inferred its phylogenetic relationship to other tea plant variants or cultivars. The cp genome had a total length of 157,097 bp and the overall GC content was 37.3%. The cp genome contained one LSC region (86,641 bp) and one SSC region (18,276 bp), which were separated by two IR regions (26,090 bp, respectively). Moreover, the cp genomes were composed of 130 genes, including 86 protein-coding genes, 36 tRNA genes, and eight rRNA genes. The phylogenetic analysis showed that LP was closely related to C. sinensis var. pabilimba cv. 'Lingyunbaihao'. This study will provide useful information for further investigating the genetic background, evolution, and breeding of LP as well as other tea cultivars and varieties.

4.
J Colloid Interface Sci ; 634: 110-120, 2023 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-36535151

RESUMO

In order to realise high ionic conductivity and improved chemical stability, a series of anion exchange membranes (AEMs) with semi-interpenetrating polymer network (sIPN) has been prepared via the incorporation of crosslinked poly(biphenyl N-methylpiperidine) (PBP) and spirobisindane-based intrinsically microporous poly(ether ketone) (PEK-SBI). The formation of phase separated structures as a result of the incompatibility between the hydrophilic PBP network and the hydrophobic PEK-SBI segment, has successfully promoted the hydroxide ion conductivity of AEMs. A swelling ratio (SR) as low as 12.2 % at 80 °C was recorded for the sIPN containing hydrophobic PEK-SBI as the linear polymer and crosslinked structure with a mass ratio of PBP to PEK-SBI of 90/10 (sIPN-90/10(PEK-SBI)). The sIPN-90/10(PEK-SBI) AEM achieved the highest hydroxide ion conductivity of 122.4 mS cm-1 at 80 °C and a recorded ion exchange capacity (IEC) of 2.26 meq g-1. Atomic force microscopy (AFM) and transmission electron microscopy (TEM) clearly revealed the improved phase separation structure of sIPN-90/10(PEK-SBI). N2 adsorption isotherm indicated that the Brunauer-Emmett-Teller (BET) surface area of the AEMs increased with the increase of microporous PEK-SBI content. Interestingly, the sIPN-90/10(PEK-SBI) AEM showed good alkaline stability for being able to maintain a conductivity of 94.7 % despite being soaked in a 1 M sodium hydroxide solution at 80 °C for 30 days. Meanwhile, a peak power density of 481 mW cm-2 can be achieved by the hydrogen/oxygen single cell using sIPN-90/10(PEK-SBI) as the AEM.


Assuntos
Éter , Etil-Éteres , Éteres , Ânions , Cetonas
5.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-981982

RESUMO

OBJECTIVES@#To study the correlation between 25-hydroxyvitamin D [25-(OH)D] and nephroblastoma in children and its value in assessing the prognosis of the disease.@*METHODS@#A total of 50 children with nephroblastoma who were admitted from January 2018 to December 2022 were included as the nephroblastoma group, and according to the postoperative pathological type, they were divided into a good prognosis group with 38 children and a poor prognosis group with 12 children. A total of 50 healthy children who underwent physical examination during the same period of time served as the healthy control group. The above groups were compared in terms of serum creatinine and 25-(OH)D level. A Spearman correlation analysis was used to investigate the correlation between serum 25-(OH)D level and therapeutic effect reaction. A multivariate logistic regression analysis was used to identify the risk factors affecting the prognosis of nephroblastoma in children.@*RESULTS@#The nephroblastoma group had significantly lower levels of serum creatinine and 25-(OH)D than the healthy control group (P<0.05). Compared with the good prognosis group, the poor prognosis group had a significantly larger tumor diameter, a significantly higher proportion of children with stage III-IV tumors, a significantly higher rate of tumor metastasis, and significantly lower serum levels of creatinine and 25-(OH)D (P<0.05). The Spearman correlation analysis showed that serum 25-(OH)D level was negatively correlated with therapeutic effect reaction (rs=-0.685, P<0.001). The multivariate logistic regression analysis showed that tumor diameter ≥10 cm, stage III-IV tumors, presence of tumor metastasis, and 25-(OH)D <19 ng/mL were closely associated with the poor prognosis of nephroblastoma in children (P<0.05). Serum 25-(OH)D level had an area under the curve of 0.805 (95%CI: 0.706-0.903, P<0.001) in evaluating the prognosis of nephroblastoma in children, with a Youden index of 0.512, a sensitivity of 0.938, and a specificity of 0.575 at the optimal cut-off value of 1.764 ng/mL.@*CONCLUSIONS@#There is a significant correlation between 25-(OH)D level and the prognosis of nephroblastoma in children, and 25-(OH)D can be used for prognosis prediction.


Assuntos
Humanos , Criança , Creatinina , Deficiência de Vitamina D/complicações , Vitamina D , Calcifediol , Prognóstico , Tumor de Wilms , Neoplasias Renais/complicações
6.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-981457

RESUMO

The present study aimed to investigate the protective role of Shaofu Zhuyu Decoction(SFZY) against endometriosis fibrosis in mice, and decipher the underlying mechanism through the phosphatase and tensin homolog deleted on chromosome ten(PTEN)/protein kinase B(Akt)/mammalian target of rapamycin(mTOR) pathway. Eighty-five BALB/c female mice were randomly assigned into a blank group, a model group, high-, medium, and low-dose SFZY(SFZY-H, SFZY-M, and SFZY-L, respectively) groups, and a gestrinone suspension(YT) group. The model of endometriosis was induced by intraperitoneal injection of uterine fragments. The mice in different groups were administrated with corresponding groups by gavage 14 days after modeling, and the blank group and model group with equal volume of distilled water by gavage. The treatment lasted for 14 days. The body weight, paw withdrawal latency caused by heat stimuli, and total weight of dissected ectopic focus were compared between different groups. The pathological changes of the ectopic tissue were observed via hematoxylin-eosin(HE) and Masson staining. Real-time PCR was employed to measure the mRNA levels of α-smooth muscle actin(α-SMA) and collagen type Ⅰ(collagen-Ⅰ) in the ectopic tissue. The protein levels of PTEN, Akt, mTOR, p-Akt, and p-mTOR in the ectopic tissue were determined by Western blot. Compared with the blank group, the modeling first decreased and then increased the body weight of mice, increased the total weight of ectopic focus, and shortened the paw withdrawal latency. Compared with the model group, SFZY and YT increased the body weight, prolonged the paw withdrawal latency, and decreased the weight of ectopic focus. Furthermore, the drug administration, especially SFZY-H and YT(P<0.01), recovered the pathological and reduced the area of collagen deposition. Compared with the blank group, the modeling up-regulated the mRNA levels of α-SMA and collagen-Ⅰ in the ectopic focus, and such up-regulation was attenuated after drug intervention, especially in the SFZY-H and YT groups(P<0.05,P<0.01). Compared with the blank group, the modeling down-regulated the protein level of PTEN and up-regulated the protein levels of Akt, mTOR, p-Akt, and p-mTOR(P<0.01, P<0.001). Drug administration, especially SFZY-H and YT, restored such changes(P<0.01). SFZY may significantly attenuate the focal fibrosis in the mouse model of endometriosis by regulating the PTEN/Akt/mTOR signaling pathway.


Assuntos
Feminino , Animais , Camundongos , Humanos , Proteínas Proto-Oncogênicas c-akt/genética , Coristoma , Endometriose/genética , Serina-Treonina Quinases TOR/genética , RNA Mensageiro , Transdução de Sinais , Peso Corporal , Mamíferos , PTEN Fosfo-Hidrolase/genética
7.
Front Immunol ; 13: 1054753, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36466888

RESUMO

Many end-stage liver disease etiologies are attributed to robust inflammatory cell recruitment. Neutrophils play an important role in inflammatory infiltration and neutrophil phagocytosis, oxidative burst, and degranulation. It has also been suggested that neutrophils may release neutrophil extracellular traps (NETs) to kill pathogens. It has been proven that neutrophil infiltration within the liver contributes to an inflammatory microenvironment and immune cell activation. Growing evidence implies that NETs are involved in the progression of numerous complications of liver transplantation, including ischemia-reperfusion injury, acute rejection, thrombosis, and hepatocellular carcinoma recurrence. NETs are discussed in this comprehensive review, focusing on their effects on liver transplantation complications. Furthermore, we discuss NETs as potential targets for liver transplantation therapy.


Assuntos
Doença Hepática Terminal , Armadilhas Extracelulares , Neoplasias Hepáticas , Transplante de Fígado , Humanos , Transplante de Fígado/efeitos adversos , Neutrófilos , Microambiente Tumoral
8.
Front Pediatr ; 10: 975628, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36275068

RESUMO

According to analyses of etiology, clinical features, diagnostic methods, and treatment strategies by summarizing a case of unexplained acute hepatitis recently experienced, we are aiming to provide some information to enrich the clinical experience in diagnosis and treatment of severe acute hepatitis of unknown etiology in young children. A boy, aged 10 years and 6 months old, was admitted to the hospital due to acute abdominal pain, jaundice, and exceptionally high levels of ALT and AST. A range of measures, including patient history, physical examination, and routine laboratory testing, were performed. Furthermore, strategies such as trio-based next-generation sequencing (Trio-NGS) and liver biopsy, as well as metagenomic NGS (mNGS) of blood and liver samples were also performed. In summary, this case was an acute severe non-A-E hepatitis that is a probable case with hepatitis of unknown origin. Immunohistochemical analysis showed an immune injury in liver tissues. Torque teno virus (TTV) sequences were detected by mNGS assay. As for treatment strategies, in addition to general treatment, this patient also underwent plasmapheresis and methylprednisolone treatment due to disease deterioration. The patient's liver function was improved afterward and discharged after one month of treatment. Taken together, this work reported the clinical feature and treatment of severe acute hepatitis with non-A-E hepatitis in detail. The potential mechanism of liver damage might be due to an immune attack in which TTV might play a role as a co-factor.

9.
FEBS Open Bio ; 11(11): 2933-2942, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34110111

RESUMO

Choroidal neovascularization (CNV) is a key characteristic of wet age-related macular degeneration (AMD) that can lead to severe vision loss in the elderly. Anti-VEGF therapy is currently the premier strategy for wet AMD, but it has limited efficacy. Previous studies have shown that chitinase-3-like-1 (YKL-40) can promote microangiogenesis and inflammation, but its effect on CNV formation has not yet been studied. Here, we investigated the potential role of YKL-40 in wet AMD and the underlying mechanism(s). We report that the serum expression of YKL-40 in wet AMD patients was significantly higher than that in control patients and was positively correlated with VEGF expression, indicating that YKL-40 may participate in the development of wet AMD. In addition, YKL-40 and VEGF expression levels were observed to be increased and the ERK1/2 pathway activated in the neuroretinal (NR) and RPE/choroid tissues of mice with laser-induced CNV. The YKL-40 and phosphorylated protein levels of the ERK1/2 pathway were decreased after intravitreal injection with an anti-YKL-40 antibody, suggesting that anti-YKL-40 could inhibit the activation of the ERK1/2 pathway. These results indicate that YKL-40 may serve as a novel target for the diagnosis and treatment of wet AMD.


Assuntos
Proteína 1 Semelhante à Quitinase-3/metabolismo , Sistema de Sinalização das MAP Quinases/fisiologia , Degeneração Macular Exsudativa/genética , Idoso , Inibidores da Angiogênese/uso terapêutico , Animais , China , Proteína 1 Semelhante à Quitinase-3/sangue , Proteína 1 Semelhante à Quitinase-3/genética , Neovascularização de Coroide/tratamento farmacológico , Neovascularização de Coroide/metabolismo , Feminino , Humanos , Inflamação , Sistema de Sinalização das MAP Quinases/genética , Degeneração Macular/genética , Degeneração Macular/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Pessoa de Meia-Idade , Neovascularização Patológica/tratamento farmacológico , Neovascularização Patológica/genética , Neovascularização Patológica/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo , Fatores de Crescimento do Endotélio Vascular/metabolismo , Degeneração Macular Exsudativa/metabolismo
10.
Mol Cell Biochem ; 476(3): 1631-1642, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33417163

RESUMO

The epithelial-mesenchymal transition (EMT) plays a significant role in fibrosis and migration of lens epithelial cells (LECs), and eventually induces posterior capsule opacification (PCO). In the past, it was generally believed that the TGF-ß/Smad pathway regulates lens EMT. A recent study found that attenuated glutathione level promotes LECs EMT via the Wnt/ß-catenin pathway, which suggests a more complex pathogenesis of PCO. To test the hypothesis, we used the mouse cataract surgery PCO model and tested both canonical Wnt/ß-catenin and TGF-ß/Smad signaling pathways. The results showed that both TGF-ß/Smad and Wnt/ß-catenin pathways were activated during the lens capsule fibrosis. Compared with the freshly isolated posterior capsule, the expression level of phosphorylated Smad2 was highest at day3 and then slightly decreased, but the expression level of Wnt10a gradually increased from day0 to day7. It shows that these two pathways are involved in the lens epithelium's fibrotic process and may play different roles in different periods. Subsequently, we established oxidative stress-induced EMT model in primary porcine lens epithelial cells and found that both the TGF-ß/Smad and Wnt/ß-catenin pathways were activated. Further study suggests that block Wnt/ß-catenin pathway using XAV939 alone or block TGF-ß/Smad pathway using LY2109761 could partially block pLECs fibrosis, but blocking Wnt/ß-catenin and TGF-ß/Smad pathway using combined XAV939 and LY2109761 could completely block pLECs fibrosis. In conclusion, this study demonstrates that both TGF-ß/Smad and canonical Wnt/ß-catenin pathways play a significant role in regulating epithelial-mesenchymal transformation of lens epithelial cells but might be in a different stage.


Assuntos
Opacificação da Cápsula/metabolismo , Células Epiteliais/metabolismo , Transição Epitelial-Mesenquimal , Cristalino/metabolismo , Estresse Oxidativo , Fator de Crescimento Transformador beta1/metabolismo , beta Catenina/metabolismo , Animais , Antioxidantes/metabolismo , Catarata , Proliferação de Células , Sobrevivência Celular , Modelos Animais de Doenças , Fibrose , Humanos , Camundongos , Oxigênio/metabolismo , Pirazóis/farmacologia , Pirróis/farmacologia , Suínos , Fator de Crescimento Transformador beta/metabolismo , Tropicamida/farmacologia , Via de Sinalização Wnt/efeitos dos fármacos
11.
Chinese Journal of Radiology ; (12): 980-985, 2020.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-868357

RESUMO

Objective:To explore the value of quantitative parameters of dynamic contrast-enhanced MRI(DCE-MRI) in evaluating the biological behavior of soft tissue tumors.Methods:The clinical data of 69 patients with soft tissue tumors confirmed by pathology in the Affiliated Hospital of Qingdao University from January 2017 to December 2019 were analyzed retrospectively, including 29 benign tumors and 40 malignant tumors. All patients were examined by routine MRI and DCE-MRI before the operation. The DCE-MRI parameters including volume transfer constant (K trans), rate constant (K ep) and extracellular space volume fraction (V e) were acquired by post-processing software analysis. Microvessel density (MVD) and Ki-67 labeling index (Ki-67 LI) were detected using immunohistoche mical method. Spearman correlation test was used to analyze the correlation between DCE-MRI quantitative parameters and MVD and Ki-67 LI.Independent sample t-test or Mann-Whitney U test was used to compare the difference of parameters between benign and malignant group, and the receiver operating characteristic (ROC) curves were performed to evaluate the diagnostic value. Results:There was positive correlation between K trans, K ep and MVD ( r=0.633, 0.727, P<0.0l), and positive correlation between K trans, K ep and Ki-67 LI ( r=0.557, 0.612, P<0.01). There was no correlation between V e and MVD, Ki-67 LI ( P>0.05). The K trans, K ep, MVD and Ki-67 LI in the malignant group were higher than those in the benign group, and the differences were significant ( P<0.05).There was no significant difference in V e value between malignant group and benign group. When K trans value of 0.169/min was used, the sensitivity, specificity and area under the ROC curve (AUC) for differentiating benign and malignant soft tissue tumors were 84.6%, 85.8% and 0.859, respectively. When K ep value of 0.367/min was used, the sensitivity, specificity and AUC were 92.3%, 83.3% and 0.846, respectively. Conclusion:The DCE-MRI quantitative parameters K trans and K ep can be used to evaluate the biological behavior of soft tissue tumors.

12.
Sci Rep ; 9(1): 14942, 2019 10 18.
Artigo em Inglês | MEDLINE | ID: mdl-31628341

RESUMO

The competition-colonization trade-off, by which species can partition spatial niches, is a potentially important mechanism allowing the maintenance of species diversity in plant communities. We examined whether there was evidence for this trade-off among tree species in a subtropical forest and how it correlated with eight functional traits. We developed and estimated a metric for colonization ability that incorporates both fecundity and seed dispersal based on seed trap data and the sizes and distributions of adult trees. Competitive ability was estimated as survival probability under high crowding conditions based on neighborhood models. Although we found no significant relationship between colonization and competitive abilities, there was a significant negative correlation between long distance dispersal ability and competitive ability at the 5 cm size class. Colonizers had traits associated with faster growth, such as large leaves and low leaf lamina density, whereas competitors had traits associated with higher survival, such as dense wood. Our results imply that any trade-off between competition and colonization may be more determined by dispersal ability than by fecundity, suggesting that seed dispersal is an important contributor to diversity maintenance. Future work should test how competitive ability covaries with the components of colonization ability, as we did here.


Assuntos
Fagaceae/fisiologia , Variação Genética , Juglandaceae/fisiologia , Lauraceae/fisiologia , Theaceae/fisiologia , Árvores/fisiologia , Florestas , Modelos Estatísticos , Fenótipo , Folhas de Planta , Probabilidade , Dispersão de Sementes , Sementes , Especificidade da Espécie , Madeira
13.
Int J Ophthalmol ; 12(3): 457-463, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30918816

RESUMO

AIM: To investigate serum levels of soluble CD146 (sCD146) and vascular endothelial growth factor receptor 2 (VEGFR2) in patients with age-related macular degeneration (AMD). METHODS: Eighty-eight patients with exudative AMD and 45 sex- and age-matched healthy controls were enrolled in this study conducted in China. Serum samples was obtained from the patients with exudative AMD and from the controls. Serum sCD146 and VEGFR2 protein levels were measured using an enzyme-linked immunosorbent assay. RESULTS: We found that serum sCD146 and VEGFR2 protein levels were significantly higher in the patients with exudative AMD group than in the controls (t=3.859, P<0.001 and t=3.829, P<0.001, respectively). Serum sCD146 levels were significantly higher in patients with classic choroidal neovascularization (CNV) than in those with occult CNV (t=9.899, P<0.001). There was a significant difference in the trend for exudative AMD in the highest versus lowest quartile of circulating sCD146 levels (χ 2=10.29, P=0.001). The receiver operating characteristic curve analysis showed that the area under the curve was 0.696 for sCD146 (95%CI: 0.601-0.791) with an optimum diagnostic cut-off value of 157.16 ng/mL, a sensitivity of 55.7%, and a specificity of 82.2%. CONCLUSION: The serum sCD146 level increases and may be a biomarker for exudative AMD.

14.
Macromolecules ; 51(21): 8887-8898, 2018 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-30956354

RESUMO

Hydrogels formed by polyelectrolyte complexation (PEC) of oppositely charged biopolymers, free of any chemical additives, are promising biomaterials. In this work, the mechanical behavior of hydrogels consisting of positively charged chitosan and negatively charged sodium hyaluronate (HA) at balanced charge composition is investigated. These hydrogels exhibit strong tensile strain and strain rate dependence. They are elastic-like, independent of the strain rate at small strain, but exhibit plastic-like behavior above the yield point by showing a monotonous decrease of the stress. The cyclic tensile test demonstrates that these hydrogels exhibit small and quickly recoverable hysteresis in the elastic-like region, but large and partially recoverable hysteresis above the yield point. The stress relaxation experiment shows a plateau in the reduced stress followed by an abrupt fracture, and the time-to-failure decreases exponentially with increasing applied step-strain. Such elastic-to-plastic-like transformation of the biopolymer PEC gels is quite different from the behaviors of PEC hydrogels formed by oppositely charged vinyl-type synthetic polyelectrolytes due to the difference in flexibility, charge density, and ionic bond strength of these polymers.

15.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-665267

RESUMO

Objective To investigate the effect of early-stage acupuncture therapy on local glucose metabolism in model rats with cerebral ischemia. Methods Eighty three-month-old SD rats were randomly divided into 4 groups,namely normal group,model group,2-h acupuncture group and 24-h acupuncture group,20 rats in each group. Craniotomy was used to establish the rat model of acute cerebral ischemia. Acupuncture treatment was carried out on acupoint of Baihui(GV20)and Renzhong(DU26)with reducing method,needle twirling and rotating frequency being 120 times per minute,once every other 4 min and for one min,and the total needling time for 30 min. Rats in 2-h acupuncture group were given acupuncture 2 h after the successful modeling,and once again after 24 h,two times in total;rats in 24-h acupuncture group were given acupuncture only for one time 24 h after successful modeling. At the end of treatment,the rat neurological function was scored,and the infarction area was measured by 2,3,5-triphenyltetrazole chloride (TTC)staining. The protein expression levels of glucose transporter(GLUT)1 and 3 in ischemic brain tissue were detected by immunohistochemistry. Results Compared with the normal group, the scores of neurological function in the model group were increased;TTC staining results showed that the left hemisphere was swollen,and the infarct volume was significantly larger than that of the contralateral side;immunohistochemical results showed that the GLUT1 and GLUT3 expression levels in the ischemic brain tissue were increased(P < 0.01). Compared with the model group,2-h acupuncture group and 24-h acupuncture group could effectively improve the cerebral ischemia, reduce the neurological function indexes and infarction area showed by TTC staining,and increase the expression levels of GLUT1 and GLUT3 in ischemic brain tissue significantly (P<0.05). And the therapeutic effect of 2-h acupuncture group was superior to that of 24-h acupuncture group(P<0.05). Conclusion Acupuncture can effectively improve cerebral ischemia in rats with acute cerebral ischemia. Acupuncture can improve the energy metabolism of ischemic brain tissue by up-regulating the protein expression of cerebral GLUT1 and GLUT3 and by increasing the blood-brain barrier transport efficiency for glucose,thus to promote glucose metabolism and provide energy for ischemic brain tissue to relieve relatively inadequate energy, and to protect against cerebral ischemic injury. Early acupuncture intervention exerts a positive effect on regulating energy metabolism of rats with cerebral ischemia.

16.
Inflamm Res ; 66(6): 523-534, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28361293

RESUMO

OBJECTIVE: To investigate whether activation of the liver X receptors (LXRs) inhibits amyloid ß1-40 (Aß1-40) induced inflammatory and senescent responses in human retinal pigment epithelial (RPE) cells. MATERIALS AND METHODS: Confluent cultures of human primary RPE and ARPE-19 cells pretreated with 5 µΜ of TO901317 (TO90), a synthetic agonist of LXR, or vehicle were incubated with 1 µΜ of Aß1-40 or Aß40-1. The optimum concentrations of Aß1-40 and TO90 were determined by cell viability assay. Pro-inflammatory cytokines IL-6, IL-8, MCP-1 were detected by real-time polymerase chain reaction (PCR) and enzyme-linked immunosorbent assay (ELISA). Expression and localization of an aging protein p16INK4a (p16) were analyzed by western blotting and immunofluorescence. Expressions of LXRs and one of their target genes ATP-binding cassette transporter A1 (ABCA1) were examined by real-time PCR and western blotting. Phosphorylated transcription inhibition factor-κB-α (p-IκB-α) was assessed by western blotting. RESULTS: A negative linear relationship between the Aß1-40 concentration and the cell viability was evident, indicating Aß1-40 decreased ARPE-19 cell viability in a dose-dependent manner. Aß1-40 enhanced the expression of IL-6, IL-8, MCP-1 as well as p16 in both RPE cell lines at both mRNA and protein levels, whereas TO90 counteracted the detrimental effects. TO90 upregulated the expression of LXRα and its target gene ABCA1, but it did not affect the expression of LXRß. Meanwhile, TO90 inhibited the phosphorylation of IκB-α mediated by Aß1-40 stimulation. CONCLUSION: Activation of the LXRα-ABCA1 axis may alleviate Aß1-40 induced inflammatory and senescent responses in RPE cells. The beneficial effect appears associated with the inhibition of the NF-κB signaling pathway.


Assuntos
Peptídeos beta-Amiloides/farmacologia , Citocinas/metabolismo , Células Epiteliais/fisiologia , Hidrocarbonetos Fluorados/farmacologia , Receptores X do Fígado/agonistas , Fragmentos de Peptídeos/farmacologia , Epitélio Pigmentado da Retina/citologia , Sulfonamidas/farmacologia , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Senescência Celular , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Humanos , Inflamação/metabolismo , Receptores X do Fígado/metabolismo , Degeneração Macular , NF-kappa B/metabolismo
17.
PLoS One ; 9(4): e95703, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24748022

RESUMO

BACKGROUND: Ecologists have been monitoring community dynamics with the purpose of understanding the rates and causes of community change. However, there is a lack of monitoring of community dynamics from the perspective of phylogeny. METHODS/PRINCIPLE FINDINGS: We attempted to understand temporal phylogenetic turnover in a 50 ha tropical forest (Barro Colorado Island, BCI) and a 20 ha subtropical forest (Dinghushan in southern China, DHS). To obtain temporal phylogenetic turnover under random conditions, two null models were used. The first shuffled names of species that are widely used in community phylogenetic analyses. The second simulated demographic processes with careful consideration on the variation in dispersal ability among species and the variations in mortality both among species and among size classes. With the two models, we tested the relationships between temporal phylogenetic turnover and phylogenetic similarity at different spatial scales in the two forests. Results were more consistent with previous findings using the second null model suggesting that the second null model is more appropriate for our purposes. With the second null model, a significantly positive relationship was detected between phylogenetic turnover and phylogenetic similarity in BCI at a 10 m×10 m scale, potentially indicating phylogenetic density dependence. This relationship in DHS was significantly negative at three of five spatial scales. This could indicate abiotic filtering processes for community assembly. Using variation partitioning, we found phylogenetic similarity contributed to variation in temporal phylogenetic turnover in the DHS plot but not in BCI plot. CONCLUSIONS/SIGNIFICANCE: The mechanisms for community assembly in BCI and DHS vary from phylogenetic perspective. Only the second null model detected this difference indicating the importance of choosing a proper null model.


Assuntos
Ecossistema , Florestas , Modelos Teóricos , Clima Tropical , Algoritmos , Característica Quantitativa Herdável
18.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-636172

RESUMO

Objective To analyze the ultrasonographic features of retroperitoneal ifbrosis (RPF). Methods Totally 13 patients with retroperitoneal ifbrosis from February 2000 to October 2012 in the Long Gang central Hospital of Shenzhen were retrospectively analyzed. Results In all patients who underwent ultrasound examination, there were ten cases of idiopathic RPF and three cases of secondary RPF with abdominal tumors. In 11 cases, the masses were hypoechoic locating at retroperitoneum and surrounding the abdominal aorta without deifnitive margin. One case showed hypoechoic mass with clear boundary. In ten cases, the internal echogenicity of masses were uniform. In two cases, the internal echogenicity of masses were uneven with a small amount of ifbrous separator with slightly higher echogenicity. No blood was found in all masses. The encasement of inferior vena cava was found in three casesand the masses extended to iliac arteries in three cases. Hydronephrosis could be found in 11 patients (84.6%) and ureter dilatation was found in ten cases. Ureteral localized stenosis were found in two cases. Conclusion Ultrasonography is a preferred imaging method in diagnosing RPF.

19.
PLoS One ; 7(12): e52596, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23300714

RESUMO

Tree size distributions have long been of interest to ecologists and foresters because they reflect fundamental demographic processes. Previous studies have assumed that size distributions are often associated with population trends or with the degree of shade tolerance. We tested these associations for 31 tree species in a 20 ha plot in a Dinghushan south subtropical forest in China. These species varied widely in growth form and shade-tolerance. We used 2005 and 2010 census data from that plot. We found that 23 species had reversed J shaped size distributions, and eight species had unimodal size distributions in 2005. On average, modal species had lower recruitment rates than reversed J species, while showing no significant difference in mortality rates, per capita population growth rates or shade-tolerance. We compared the observed size distributions with the equilibrium distributions projected from observed size-dependent growth and mortality. We found that observed distributions generally had the same shape as predicted equilibrium distributions in both unimodal and reversed J species, but there were statistically significant, important quantitative differences between observed and projected equilibrium size distributions in most species, suggesting that these populations are not at equilibrium and that this forest is changing over time. Almost all modal species had U-shaped size-dependent mortality and/or growth functions, with turning points of both mortality and growth at intermediate size classes close to the peak in the size distribution. These results show that modal size distributions do not necessarily indicate either population decline or shade-intolerance. Instead, the modal species in our study were characterized by a life history strategy of relatively strong conservatism in an intermediate size class, leading to very low growth and mortality in that size class, and thus to a peak in the size distribution at intermediate sizes.


Assuntos
Árvores/anatomia & histologia , Árvores/crescimento & desenvolvimento , Algoritmos , China , Interpretação Estatística de Dados , Ecossistema , Agricultura Florestal , Modelos Biológicos , Especificidade da Espécie
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