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Competitive effect, but not competitive response, varies along a climatic gradient depending on tree species identity
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作者 Teresa Valor Lluís Coll +9 位作者 David I.Forrester Hans Pretzsch Miren del Río Kamil Bielak Bogdan Brzeziecki Franz Binder Torben Hilmers Zuzana Sitková Roberto Tognetti Aitor Ameztegui 《Forest Ecosystems》 SCIE CSCD 2024年第2期142-151,共10页
Background: Understanding the role of species identity in interactions among individuals is crucial for assessing the productivity and stability of mixed forests over time. However, there is limited knowledge concerni... Background: Understanding the role of species identity in interactions among individuals is crucial for assessing the productivity and stability of mixed forests over time. However, there is limited knowledge concerning the variation in competitive effect and response of different species along climatic gradients. In this study, we investigated the importance of climate, tree size, and competition on the growth of three tree species: spruce(Picea abies), fir(Abies alba), and beech(Fagus sylvatica), and examined their competitive response and effect along a climatic gradient.Methods: We selected 39 plots distributed across the European mountains with records of the position and growth of 5,759 individuals. For each target species, models relating tree growth to tree size, climate and competition were proposed. Competition was modelled using a neighbourhood competition index that considered the effects of inter-and intraspecific competition on target trees. Competitive responses and effects were related to climate.Likelihood methods and information theory were used to select the best model.Results: Our findings revealed that competition had a greater impact on target species growth than tree size or climate. Climate did influence the competitive effects of neighbouring species, but it did not affect the target species? response to competition. The strength of competitive effects varied along the gradient, contingent on the identity of the interacting species. When the target species exhibited an intermediate competitive effect relative to neighbouring species, both higher inter-than intraspecific competitive effects and competition reduction occurred along the gradient. Notably, species competitive effects were most pronounced when the target species' growth was at its peak and weakest when growing conditions were far from their maximum.Conclusions: Climate modulates the effects of competition from neighbouring trees on the target tree and not the susceptibility of the target tree to competition. The modelling approach should be useful in future research to expand our knowledge of how competition modulates forest communities across environmental gradients. 展开更多
关键词 Competition coefficient Competition reduction Interspecific competition Intraspecific competition Mixing effects Mixed species forest Neighbourhood models Plant-plant interactions
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Genomic analysis of indigenous goats in Southwest Asia reveals evidence of ancient adaptive introgression related to desert climate
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作者 Hojjat Asadollahpour Nanaei Yudong Cai +8 位作者 Akil Alshawi Jiayue Wen Tanveer Hussain Wei-Wei Fu Nai-Yi Xu Abdulameer Essa Johannes ALenstra Xihong Wang Yu Jiang 《Zoological Research》 SCIE CAS CSCD 2023年第1期20-29,共10页
Understanding how evolutionary pressures related to climate change have shaped the current genetic background of domestic animals is a fundamental pursuit of biology. Here, we generated wholegenome sequencing data fro... Understanding how evolutionary pressures related to climate change have shaped the current genetic background of domestic animals is a fundamental pursuit of biology. Here, we generated wholegenome sequencing data from native goat populations in Iraq and Pakistan. Combined with previously published data on modern, ancient(Late Neolithic to Medieval periods), and wild Capra species worldwide, we explored the genetic population structure, ancestry components, and signatures of natural positive selection in native goat populations in Southwest Asia(SWA). Results revealed that the genetic structure of SWA goats was deeply influenced by gene flow from the eastern Mediterranean during the Chalcolithic period, which may reflect adaptation to gradual warming and aridity in the region. Furthermore, comparative genomic analysis revealed adaptive introgression of the KITLG locus from the Nubian ibex(C. nubiana) into African and SWA goats. The frequency of the selected allele at this locus was significantly higher among goat populations located near northeastern Africa. These results provide new insights into the genetic composition and history of goat populations in the SWA region. 展开更多
关键词 GOAT Adaptation KITLG Southwest Asia Nubian ibex
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Basic leucine zipper gene VvbZIP61 is expressed at a quantitative trait locus for high monoterpene content in grape berries
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作者 Yuyu Zhang Cuixia Liu +7 位作者 Xianju Liu Zemin Wang Yi Wang Gan-yuan Zhong Shaohua Li Zhanwu Dai Zhenchang Liang Peige Fan 《Horticulture Research》 SCIE CSCD 2023年第9期55-67,共13页
The widely appreciated muscat flavor of grapes and wine is mainly attributable to the monoterpenes that accumulate in ripe grape berries.To identify quantitative trait loci(QTL)for grape berry monoterpene content,an F... The widely appreciated muscat flavor of grapes and wine is mainly attributable to the monoterpenes that accumulate in ripe grape berries.To identify quantitative trait loci(QTL)for grape berry monoterpene content,an F1 mapping population was constructed by a cross between two grapevine genotypes,one with neutral aroma berries(cv.‘Beifeng’)and the other with a pronounced muscat aroma(elite Vitis vinifera line‘3–34’).A high-density genetic linkage map spanning 1563.7 cM was constructed using 3332 SNP markers that were assigned to 19 linkage groups.Monoterpenes were extracted from the berry of the F1 progeny,then identified and quantified by gas chromatography–mass spectrometry.Twelve stable QTLs associated with the amounts of 11 monoterpenes in berries were thus identified.In parallel,the levels of RNA in berries from 34 diverse cultivars were estimated by RNA sequencing and compared to the monoterpene content of the berries.The expression of five genes mapping to stable QTLs correlated well with the monoterpene content of berries.These genes,including the basic leucine zipper VvbZIP61 gene on chromosome 12,are therefore considered as potentially being involved in monoterpene metabolism.Overexpression of VvbZIP61 in Vitis amurensis callus through Agrobacterium-mediated transformation significantly increased the accumulation of several monoterpenes in the callus,including nerol,linalool,geranial,geraniol,β-myrcene,and D-limonene.It is hypothesized that VvbZIP61 expression acts to increase muscat flavor in grapes.These results advance our understanding of the genetic control of monoterpene biosynthesis in grapes and provide important information for the marker-assisted selection of aroma compounds in grape breeding. 展开更多
关键词 CONTENT LINKAGE NEUTRAL
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Utilizing Iso-Value Field Curves in Lieu of Magnetic Field Lines Amid Infinite and Parallel Electrical Wires
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作者 Geoffroy Auvert 《Open Journal of Applied Sciences》 2024年第1期70-84,共15页
Building on a new model proposed recently for calculating constant electro-magnetic field values, the present article explores the electro-magnetic field configuration generated by parallel electrical wires. This impo... Building on a new model proposed recently for calculating constant electro-magnetic field values, the present article explores the electro-magnetic field configuration generated by parallel electrical wires. This imposes a reevaluation of the drawing procedure for constructing field curves with a constant field values around multiple parallel electrical conducting wires. To achieve this, we employ methods akin to those used for creating contours on topographical maps, ensuring a consistent numerical field value along the entire length of the field curves. Subsequent calculations will be conducted for scenarios where wires are not parallel. 展开更多
关键词 Specific Field Value Parallel Electrical Wires Magnetic Field Vector Field around Parallel Wires Topographic Level Map
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Detection of Burned Areas through Spectral Indices Analysis of Sentinel-2A Satellite Images in the Abokouamékro Wildlife Reserve (Central, Côte D’Ivoire)
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作者 Bob Kouakou Kouadio Sié Ouattara +3 位作者 Alain Clément Jean-Marc Gala Bi Zaouri Jean-Luc Kouadio Kouassi Jean-Luc Edouard Kouakou N’guessan 《Open Journal of Applied Sciences》 2024年第1期205-222,共18页
In Côte d’Ivoire, the recurring and unregulated use of bushfires, which cause ecological damage, presents a pressing concern for the custodians of protected areas. This study aims to enhance our comprehension of... In Côte d’Ivoire, the recurring and unregulated use of bushfires, which cause ecological damage, presents a pressing concern for the custodians of protected areas. This study aims to enhance our comprehension of the dynamics of burnt areas within the Abokouamékro Wildlife Reserve (AWR) by employing the analysis of spectral indices derived from satellite imagery. The research methodology began with the calculation of mean indices and their corresponding spectral sub-indices, including NDVI, SAVI, NDWI, NDMI, BAI, NBR, TCW, TCG, and TCB, utilizing data from the Sentinel-2A satellite image dated January 17, 2022. Subsequently, a fuzzy classification model was applied to these various indices and sub-indices, guided by the degree of membership α, with the goal of effectively distinguishing between burned and unburned areas. Following the classification, the accuracies of the classified indices and sub-indices were validated using the coordinates of 100 data points collected within the AWR through GPS technology. The results revealed that the overall accuracy of all indices and sub-indices declines as the degree of membership α decreases from 1 to 0. Among the mean spectral indices, NDVI-mean, SAVI-mean, NDMI-mean exhibited the highest overall accuracies, achieving 97%, 95%, and 90%, respectively. These results closely mirrored those obtained by sub-indices using band 8 (NDVI-B8, SAVI-B8, and NDMI-B8), which yield respective overall accuracies of 93%, 92%, and 89%. At a degree of membership α = 1, the estimated burned areas for the most effective indices encompassed 2144.38 hectares for NDVI-mean, 1932.14 hectares for mean SAVI-mean, and 4947.13 hectares for mean NDMI-mean. A prospective approach involving the amalgamation of these three indices could have the potential to yield improved outcomes. This study could be a substantial contribution to the discrimination of bushfires in Côte d’Ivoire. 展开更多
关键词 Spectral Indices WILDFIRE Burned Areas Abokouamékro Wildlife Reserve Côte D’Ivoire
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National Soil Organic Carbon Stocks Inventories under Different Mangrove Forest Types in Gabon
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作者 Rolf Gaël Mabicka Obame Neil-Yohan Musadji +5 位作者 Jean Hervé Mve Beh Lydie-Stella Koutika Jean Aubin Ondo Farrel Nzigou Boucka Michel Mbina Mounguengui Claude Geffroy 《Open Journal of Forestry》 2024年第2期127-140,共14页
Gabonese’s estuary is an important coastal mangrove setting and soil plays a key role in mangrove carbon storage in mangrove forests. However, the spatial variation in soil organic carbon (SOC) storage remain unclear... Gabonese’s estuary is an important coastal mangrove setting and soil plays a key role in mangrove carbon storage in mangrove forests. However, the spatial variation in soil organic carbon (SOC) storage remain unclear. To address this gap, determining the SOC spatial variation in Gabonese’s estuarine is essential for better understanding the global carbon cycle. The present study compared soil organic carbon between northern and southern sites in different mangrove forest, Rhizophora racemosa and Avicennia germinans. The results showed that the mean SOC stocks at 1 m depth were 256.28 ± 127.29 MgC ha<sup>−</sup><sup>1</sup>. Among the different regions, SOC in northern zone was significantly (p p < 0.001). The deeper layers contained higher SOC stocks (254.62 ± 128.09 MgC ha<sup>−</sup><sup>1</sup>) than upper layers (55.42 ± 25.37 MgC ha<sup>−</sup><sup>1</sup>). The study highlights that low deforestation rate have led to less CO<sub>2</sub> (705.3 Mg CO<sub>2</sub>e ha<sup>−</sup><sup>1</sup> - 922.62 Mg CO<sub>2</sub>e ha<sup>−</sup><sup>1</sup>) emissions than most sediment carbon-rich mangroves in the world. These results highlight the influence of soil texture and mangrove forest types on the mangrove SOC stocks. The first national comparison of soil organic carbon stocks between mangroves and upland tropical forests indicated SOC stocks were two times more in mangroves soils (51.21 ± 45.00 MgC ha<sup>−</sup><sup>1</sup>) than primary (20.33 ± 12.7 MgC ha<sup>−</sup><sup>1</sup>), savanna and cropland (21.71 ± 15.10 MgC ha<sup>−</sup><sup>1</sup>). We find that mangroves in this study emit lower dioxide-carbon equivalent emissions. This study highlights the importance of national inventories of soil organic carbon and can be used as a baseline on the role of mangroves in carbon sequestration and climate change mitigation but the variation in SOC stocks indicates the need for further national data. 展开更多
关键词 Mangroves Forest Soil Organic Carbon Stocks Rizophora Racemose Avicenia germinans GABON
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Characteristics of hepatic nuclear-transcription factor-kappa B expression and quantitative analysis in rat hepatocarcinogenesis 被引量:12
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作者 Wu, Wei Yao, Deng-Fu +7 位作者 Qiu, Li-Wei Sai, Wen-Li Shen, Jun-Jun Yu, Hong-Bo Wu, Xin-Hua Li, Yue-Ming Wang, Yi-Lang Gu, Wen-Jing 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS 2009年第5期504-509,共6页
BACKGROUND: Hepatocellular carcinoma (HCC) is one of the most common malignant tumors. We analyzed the expression of miclear-transcription factor-kappa B (NF-kappa B) during hepatocarcinogenesis in order to evaluate i... BACKGROUND: Hepatocellular carcinoma (HCC) is one of the most common malignant tumors. We analyzed the expression of miclear-transcription factor-kappa B (NF-kappa B) during hepatocarcinogenesis in order to evaluate its dynamic expression and its clinical value in the development and diagnosis of HCC. METHODS: Hepatoma models were induced by oral administration of 2-acetamidoflurene (2-FAA) to male Sprague-Dawley rats. Morphological changes were observed after hematoxylin and eosin staining. The cellular distribution of NF-kappa B expression during different stages of cancer development was investigated by immunohistochemistry, and the level of NF-kappa B expression in liver tissues was quantitatively analyzed by ELISA. The gene fragments of hepatic NF-kappa B were amplified by nested-polymerase chain reaction assay. RESULTS: Hepatocytes showed vacuole-like degeneration during the early stages, then had a hyperplastic nodal appearance during the middle stages, and finally progressed to tubercles of cancerous nests with high differentiation. The NF-kappa B-positive material was buff-colored, fine particles localized in the nucleus, and the incidence of NF-kappa B-positive cells was 81.8% in degeneration, 83.3% in precancerous lesions, and 100% in cancerous tissues. All of these values were higher than those in controls (P<0.01). Hepatic NF-kappa B expression and hepatic NF-kappa B-mRNA were also higher during the course of HCC development (P<0.01). CONCLUSION: The NF-kappa B signal transduction pathway is activated during the early stages of HCC development, and its abnormal expression may be associated with the occurrence of HCC. 展开更多
关键词 hepatocellular carcinoma nuclear factor-kappa B IMMUNOHISTOCHEMISTRY nested-polymerase chain reaction NF-kappa B-mRNA
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Expression of Ezrin,HGF,C-met in pancreatic cancer and non-cancerous pancreatic tissues of rats 被引量:7
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作者 Tan, Xing-Guo Yang, Zhu-Lin 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS 2010年第6期639-644,共6页
BACKGROUND: Recent studies have confirmed that the expression of Ezrin, hepatocyte growth factor (HGF) and its receptor (C-met) is related to the genesis, progress, invasion and metastasis of some malignant tumors. Re... BACKGROUND: Recent studies have confirmed that the expression of Ezrin, hepatocyte growth factor (HGF) and its receptor (C-met) is related to the genesis, progress, invasion and metastasis of some malignant tumors. Researches have also found that the biological function of Ezrin is closely related to HGF/C-met in malignant tumors. However, there is no report on the expression levels of Ezrin, HGF and C-met in rat pancreatic cancer induced by dimethylbenzanthracene (DMBA). This study aimed to detect the expression of Ezrin, HGF and C-met in rat pancreatic cancer and non-cancerous pancreatic tissues, and assess its effect in cancer induction by DMBA. METHODS: Ninety Sprague-Dawley rats were divided into 3 groups randomly: 40 in a pancreatic cancer model group (group A), 40 in a trichostatin A (TSA) intervention group (group B), and 10 in a control group (group C). DMBA was directly implanted into the parenchyma of rat pancreas in group A+group B. The rats of group B were treated with 1 ml of TSA saline solution (1 mu g/ml) via intraperitoneal injection weekly. The carcinogenesis of rats executed within 3-5 months in groups A and B was observed by macrograph and microscopy. Meanwhile, the rats in group C were executed within 5 months. The EnVision (TM) immunohistochemistry for detecting the expression levels of Ezrin, HGF and C-met was used in paraffin-embedded sections of the pancreatic specimens. RESULTS: The incidence of pancreatic cancer in group A was 48.6% and in group B 33.3%. The maximal diameter of tumor mass was significantly larger in group A than that in group B (P<0.05). No pathological changes were observed in the pancreas of group C and other main organs of groups A and B. The positive rates of Ezrin, HGF and C-met were significantly higher in ductal adenocarcinoma than in non-cancerous pancreatic tissues of groups A and B (P<0.01). The positive rates of Ezrin, HGF and C-met were significantly higher in ductal adenocarcinoma of group A than those in non-cancerous pancreatic tissues of group A (P<0.05), but there was no significant difference in group B (P>0.05). The positive rates of Ezrin, HGF and C-met in non-cancerous pancreatic tissues proved mild to severe atypical hyperplasia of the ductal epithelia. The pancreas of group C and 2 cases of fibrosarcoma showed the negative expression of Ezrin, HGF and C-met. There was a trend of consistency in the expression of Ezrin, HGF and C-met in ductal adenocarcinoma (P<0.05 or P<0.01). CONCLUSIONS: DMBA directly implanted into the parenchyma of the pancreas can produce a model of pancreatic cancer with a high incidence in a short time. TSA might inhibit the carcinogenesis and growth of pancreatic cancer, and its effects may be related to the inhibition of the expression of Ezrin, HGF and C-met during the process. Ezrin, HGF and C-met may have positive effects on the carcinogenesis of rat pancreas. (Hepatobiliary Pancreat Dis Int 2010; 9: 639-644) 展开更多
关键词 pancreatic neoplasms animal model EZRIN hepatocyte growth factor C-MET
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Proteomic profiling of fetal esophageal epithelium, esophageal cancer, and tumor-adjacent esophageal epithelium and immunohistochemical characterization of a representative differential protein, PRX6 被引量:7
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作者 Jun-Hui Guo Guo-Lan Xing +5 位作者 Xin-Hui Fang Hui-Fang Wu Bo Zhang Jin-Zhong Yu Zong-Min Fan Li-Dong Wang 《World Journal of Gastroenterology》 SCIE CAS 2017年第8期1434-1442,共9页
AIM To understand the molecular mechanism of esophageal cancer development and provide molecular markers for screening high-risk populations and early diagnosis. METHODS Two-dimensional electrophoresis combined with m... AIM To understand the molecular mechanism of esophageal cancer development and provide molecular markers for screening high-risk populations and early diagnosis. METHODS Two-dimensional electrophoresis combined with mass spectrometry were adopted to screen differentially expressed proteins in nine cases of fetal esophageal epithelium, eight cases of esophageal cancer, and eight cases of tumor-adjacent normal esophageal epithelium collected from fetuses of different gestational age, or esophageal cancer patients from a high-risk area of esophageal cancer in China. Immunohistochemistry(avidin-biotin-horseradish peroxidase complex method) was used to detect the expression of peroxiredoxin(PRX)6 in 91 cases of esophageal cancer, tumoradjacent normal esophageal tissue, basal cell hyperplasia, dysplasia, and carcinoma in situ, as well as 65 cases of esophageal epithelium from fetuses at a gestational age of 3-9 mo.RESULTS After peptide mass fingerprint analysis and search of protein databases, 21 differential proteins were identified; some of which represent a protein isoform. Varying degrees of expression of PRX6 protein, which was localized mainly in the cytoplasm, were detected in adult and fetal normal esophageal tissues, precancerous lesions, and esophageal cancer. With the progression of esophageal lesions, PRX6 protein expression showed a declining trend(P < 0.05). In fetal epithelium from fetuses at gestational age 3-6 mo, PRX6 protein expression showed a declining trend with age(P < 0.05). PRX6 protein expression was significantly higher in well-differentiated esophageal cancer tissues than in poorly differentiated esophageal cancer tissues(P < 0.05).CONCLUSION Development and progression of esophageal cancer result from interactions of genetic changes(accumulation or superposition). PRX6 protein is associated with fetal esophageal development and cancer differentiation. 展开更多
关键词 胎儿的食道的上皮 食道的有鳞的房间癌 肿瘤邻近的食道的上皮 Proteomics
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Selective blockade of NF-kappa B by novel mutated I kappa B alpha suppresses CD3/CD28-induced activation of memory CD4(+) T cells in asthma 被引量:40
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作者 Zhou,L. F. Zhang,M. S. +2 位作者 Hu,A. H. Zhu Z. Yin,K. S. 《南京医科大学学报(自然科学版)》 CAS CSCD 北大核心 2008年第6期826-826,共1页
Background:Nuclear factor kappa B(NF-kappa B) overactivation plays a crucial role in T-helper 2 (Th2)-biased allergic airway inflammation by increased activation and decreased apoptosis of CD4(+) T cells. We have show... Background:Nuclear factor kappa B(NF-kappa B) overactivation plays a crucial role in T-helper 2 (Th2)-biased allergic airway inflammation by increased activation and decreased apoptosis of CD4(+) T cells. We have shown that targeted NF-kappa B suppression in dendritic cells by adenoviral gene transfer of a novel mutated inhibitor of NF-kappa B(I kappa B alpha) (AdI kappa B alpha M) contributes to T-cell tolerance, but the immunosuppressive action of AdI kappa B alpha M on memory(CD45RO(+)) CD4(+) T cells remains enigmatic. Methods:CD45RO(+) T cells from Dermatophagoides farinaei-sensitized asthmatic patients, untransfected or transfected with AdI kappa B alpha M or AdLacZ(beta-galactosidase) for 24 h, were stimulated with anti-CD3(1.0 mu g/ml) plus anti-CD28(0.5 mu g/ml) monoclonal antibody for an additional 24 h. I kappa B alpha M transgene expression and NF-kappa B activation were detected by polymerase chain reaction(PCR), reverse transcription-PCR(RT-PCR), Western blot analysis, and electrophoretic mobility shift assay. Phenotype and apoptosis were measured by flow cytometry, annexin V binding, and terminal deoxyribonucleotidyl transferase-mediated dUTP nick end labeling analyses. Cytokine production and cell proliferation were determined using enzyme-linked immunosorbent assay andH-3 thymidine incorporation. Results:A unique 801-bp I kappa B alpha M cDNA and a dose-dependent increase in I kappa B alpha M transgene expression were observed in AdI kappa B alpha M-transfected CD45RO(+) T cells. Significantly, AdI kappa B alpha M inhibited CD3/CD28-mediated NF-kappa B activation in CD45RO(+) T cells, leading to evident apoptosis, reduction of eotaxin, RANTES, Th1 interferon (IFN)-gamma and interleukin (IL)-2, and Th2 (IL-4, IL-5, and IL-13 despite a slight decrease in IL-10) cytokines and secondary proliferative response. AdI kappa B alpha M also upregulated cytotoxic T lymphocyte-associated antigen 4(CTLA-4) and downregulated CD69 besides no change in CD28. Conclusion:I kappa B alpha M might be beneficial to augment memory CD4(+) T-cell tolerance through modulating B7-CD28/CTLA-4 co-stimulatory pathways and NF-kappa B-dependent cytokine profiles in allergic inflammatory diseases including asthma. 展开更多
关键词 哮喘 治疗方法 临床分析 T细胞
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A comparative study of four 20-membered N_2S_4-crown ethers as ionophores for polymeric membrane silver selective electrodes 被引量:4
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作者 Zhang, Jun Yu, Shun Yang +2 位作者 Yin, Tan Ji Hu, Xue Feng Qin, Wei 《Chinese Chemical Letters》 SCIE CAS CSCD 2010年第4期464-467,共4页
Four 20-membered N_2S_4-monoazathiacrown ethers have been synthesized and explored as neutral ionophores for Ag^+-selective electrodes.Potentiometric responses reveal that the flexibility of the ligands has great effe... Four 20-membered N_2S_4-monoazathiacrown ethers have been synthesized and explored as neutral ionophores for Ag^+-selective electrodes.Potentiometric responses reveal that the flexibility of the ligands has great effect on the selectivity and sensitivity to Ag^+ ions.The electrode based on ionophore 9,10,20,25-tetrahydro-5H,12H-tribenzo[b,n,r][1,7,10,16,4,13]tetrathiadiaza cycloicosine 6,13-(7H,14H)-dione(C) with 2-nitrophenyl octyl ether(o-NPOE) as solvent in a poly(vinyl chloride)(PVC) membrane matrix sho... 展开更多
关键词 Ion-selective electrodes SILVER IONOPHORE Azathiacrown ether
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Repressing malic enzyme 1 redirects glucose metabolism,unbalances the redox state,and attenuates migratory and invasive abilities in nasopharyngeal carcinoma cell lines 被引量:4
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作者 Fang-Jing Zheng Hao-Bin Ye +3 位作者 Man-Si Wu Yi-Fan Lian Chao-Nan Qian Yi-Xin Zeng 《Chinese Journal of Cancer》 SCIE CAS CSCD 2012年第11期519-531,共13页
A large amount of nicotinamide adenine dinucleotide phosphate(NADPH) is required for fatty acid synthesis and maintenance of the redox state in cancer cells.Malic enzyme 1(ME1)-dependent NADPH production is one of the... A large amount of nicotinamide adenine dinucleotide phosphate(NADPH) is required for fatty acid synthesis and maintenance of the redox state in cancer cells.Malic enzyme 1(ME1)-dependent NADPH production is one of the three pathways that contribute to the formation of the cytosolic NADPH pool.ME1 is generally considered to be overexpressed in cancer cells to meet the high demand for increased de novo fatty acid synthesis.In the present study,we found that glucose induced higher ME1 activity and that repressing ME1 had a profound impact on glucose metabolism of nasopharyngeal carcinoma(NPC) cells.High incorporation of glucose and an enhancement of the pentose phosphate pathway were observed in ME1-repressed cells.However,there were no obvious changes in the other two pathways for glucose metabolism:glycolysis and oxidative phosphorylation.Interestingly,NADPH was decreased under low-glucose condition in ME1-repressed cells relative to wild-type cells,whereas no significant difference was observed under high-glucose condition.ME1-repressed cells had significantly decreased tolerance to low-glucose condition.Moreover,NADPH produced by ME1 was not only important for fatty acid synthesis but also essential for maintenance of the intracellular redox state and the protection of cells from oxidative stress.Furthermore,diminished migration and invasion were observed in ME1-repressed cells due to a reduced level of Snail protein.Collectively,these results suggest an essential role for ME1 in the production of cytosolic NADPH and maintenance of migratory and invasive abilities of NPC cells. 展开更多
关键词 氧化还原状态 鼻咽癌细胞 苹果酸酶 细胞株 葡萄糖 糖代谢 还原型烟酰胺腺嘌呤二核苷酸 侵袭
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Rapid induction of PC3/BTG2 gene by hepatopoietin or partial hepatectomy and its mRNA expression in hepatocellular carcinoma 被引量:2
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作者 Zhang, Zhi-Min Wang, Ge +7 位作者 Chen, Chuan Yang, Zhi-Xiang Jin, Feng San, Jin-Lu Xu, Wen Li, Qiong Li, Zeng-Peng Wang, Dong 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS 2009年第3期288-293,共6页
BACKGROUND: The anti-proliferative gene, PC3 (pheochromocytoma cell 3)/BTG2 (B-cell translocation gene 2), is one of the early growth response genes and belongs to the BTG/Tob protein family. This study aimed to asses... BACKGROUND: The anti-proliferative gene, PC3 (pheochromocytoma cell 3)/BTG2 (B-cell translocation gene 2), is one of the early growth response genes and belongs to the BTG/Tob protein family. This study aimed to assess the effects of recombinant human hepatopoietin (HPO) and partial hepatectomy on rapidly induced expression of immediate-early genes and to investigate the expression of PC3/BTG2 mRNA in hepatocellular carcinoma (HCC) at different stages of progression. METHODS: After a rat model of partial hepatectomy was established, we investigated gene expression within I hour after 2/3 partial hepatectomy by representational difference analysis and in a primary cultured hepatocyte system. The expression levels of PC3/BTG2 from liver tissues of the rat model were assessed by RT-PCR and Northern blotting. Meanwhile, the expression of BTG2 mRNA in a tissue microarray of HCC was determined by in situ hybridization. RESULTS: The PC3/BTG2 gene was rapidly induced after 2/3 partial hepatectomy and its expression peaked within 1-2 hours after operation. HPO rapidly induced the expression of the genes c-fos, LRF-1, and PC3 in primary cultured rat hepatocytes, which might be one of the molecular mechanisms by which HPO stimulates hepatocyte proliferation. Positive BTG2 mRNA expression was detected in 71.19% (42/59) of the HCC samples and in 75% (3/4) of the normal liver tissue samples obtained from the region around the HCC tissues. PC3/BTG2 mRNA was located mainly in the cytoplasm of HCC cells and its expression was related to the degree of differentiation. CONCLUSIONS: Recombinant human HPO and partial hepatectomy rapidly induce the expression of the PC3/BTG2 gene. PC3/BTG2 mRNA is highly expressed in HCC cells and its expression is related to the degree of cell differentiation. The abnormal expression of PC3/BTG2 is closely related to the genesis and development of HCC, so PC3/BTG2 may play an important role in these processes. (Hepatobilimy Pancreat Dis Int 2009; 8: 288-293) 展开更多
关键词 HEPATOPOIETIN liver regeneration HEPATECTOMY hepatocellular carcinoma PC3/BTG2
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Dynamic expression of rat heat shock protein gp96 and its gene during development of hepatocellular carcinoma 被引量:3
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作者 Wu, Xin-Hua Yao, Deng-Fu +5 位作者 Su, Xiao-Qin Tai, Bo-Jun Huang, Hua Qiu, Li-Wei Wu, Wei Shao, Yi-Xiang 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS 2007年第6期616-621,共6页
BACKGROUND: Hepatocellular carcinoma (HCC) is characterized by multicause, obvious multistage and multifocal processes of tumor progression. The development of HCC is related intimately to overexpression and signal tr... BACKGROUND: Hepatocellular carcinoma (HCC) is characterized by multicause, obvious multistage and multifocal processes of tumor progression. The development of HCC is related intimately to overexpression and signal transduction of many cellular factors. This study was undertaken to investigate the dynamic expression and alteration of heat shock protein (HSP) gp96 along with its gene during HCC development. METHODS: A rat model of hepatoma induced with 2-fluorenylacetamide (2-FAA, 0.05%) was established in male Sprague-Dawley rats. Total RNA and pathological changes were observed during hepatocarcinogenesis. Total RNAs were transcribed into cDNA by reverse transcription and the gene fragment of gp96 was amplified by nested RT-PCR. The gp96 expression in rat liver tissues was semi-quantitatively analyzed by immunohistochemistry. RESULTS: Histological examination suggested that hepatocytes in rats fed with 2-FAA showed vacuole-like denaturation at the early stages, then dysplastic nodules appeared at the middle stage, and finally progressed to tubercles of cancerous nests. A tendency of increasing liver gp96 protein level was found from normal liver to precancerous to cancerous tissues during hepatoma development (P<0.01), and was in accordance with the changes in gp96 mRNA (P<0.05). CONCLUSION: HSP gp96 is involved in HCC development and its overexpression may be a useful marker for early diagnosis. 展开更多
关键词 hepatocellular carcinoma HSP gp96 RT-PCR IMMUNOHISTOCHEMISTRY
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Insights into tertiary lymphoid structures in the solid tumor microenvironment: anti-tumor mechanism, functional regulation, and immunotherapeutic strategies 被引量:3
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作者 Hua Zhao Hao Wang +1 位作者 Qiuru Zhou Xiubao Ren 《Cancer Biology & Medicine》 SCIE CAS CSCD 2021年第4期981-991,共11页
Tertiary lymphoid structures(TLSs)are ectopic immune cell aggregations that develop in peripheral tissues in response to a wide range of chronic inflammatory conditions,including infection,autoimmune disease,and cance... Tertiary lymphoid structures(TLSs)are ectopic immune cell aggregations that develop in peripheral tissues in response to a wide range of chronic inflammatory conditions,including infection,autoimmune disease,and cancer.In the tumor microenvironment(TME),the structures of TLSs,including B-cell-and T-cell-enriched areas indicate that the TLSs might be the local site during the initiation and maintenance of humoral and cellular immune responses against cancers.Numerous studies have evaluated the expression of TLSs in different cancer patients and their association with prognoses of cancer patients.It was shown that welldeveloped TLSs characterized by mature B cells synthesized tumor specific antibodies,which were considered as specific markers for a good prognosis.However,there are still some immunosuppressive factors existing in the TLSs that may affect anti-tumor responses.These factors include dysfunctional B cells,regulatory T cells,and T follicular regulatory cells.The complexity and heterogeneity of the TLS composition may affect the function and activity of TLSs;it is therefore essential to fully understand the function and influencing factors in TLSs.It has been reported that checkpoint inhibitors and vaccines are currently being developed to reprogram the TME by establishing mature TLSs to improve cancer immunotherapies.In this review,we focused on recent advances in TLSs in human solid tumors,including structural characteristics and classes,antitumor mechanisms,immunosuppressive factors,and TLSbased therapeutic approaches. 展开更多
关键词 Tertiary lymphoid structure tumor microenvironment IMMUNOTHERAPY B cells T cells
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Baicalin and jasminoidin effects on gene expression and compatibility in the hippocampus following focal cerebral ischemia 被引量:2
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作者 Guo, Lin Meng, Fanyun +4 位作者 Zhang, Guodong Zhao, Jing Zhang, Zhanjun Zhou, Caixiu Wang, Zhong 《Neural Regeneration Research》 SCIE CAS CSCD 2011年第3期165-170,共6页
The compound traditional Chinese medicine Qingkailing, which is an ingredient used to treat cerebral ischemia, has been limited to studies concerning single genes or single pathways. Interactions and pharmacological m... The compound traditional Chinese medicine Qingkailing, which is an ingredient used to treat cerebral ischemia, has been limited to studies concerning single genes or single pathways. Interactions and pharmacological mechanisms of the compound ingredients (baicalin and jasminoidin) remain poorly understood. In the present study, baicalin and jasminoidin, as well as the combination, were used to separately treat mouse models of cerebral ischemia, cDNA microarray analyses of 374 cerebral ischemia-related genes were utilized to determine changes in gene-expression profiles. Arraytrack 3.40 and Ingenuity Pathway Analysis (IPA) databases were utilized to analyze changes in gene molecular functions and network path functions. Baicalin or jasminoidin alone effectively reduced infarct area, and the combination resulted in significantly better outcomes. IPA showed inhibited cell apoptosis in the baicalin group and Ca^2+ channel regulation in the jasminoidin group. The combination of baicalin and jasminoidin activated HTR3A and F5 expression, regulated Ca^2+ channels, activated kappa light polypeptide gene enhancer inhibitor IKBKG in B cells to control IkB kinase/nuclear factor-kB cascade, suppressed activation of inflammatory cytokine interleukin-6 receptors and activated transduction of guanine-nucleotide- binding protein (G protein) signal. Results suggested that the combination of baicalin and jasminoidin resulted in similar molecular mechanisms to baicalin and jasminoidin alone. However, novel pharmacological actions of compatibility were detected, demonstrating significant protection against cerebral ischemia. 展开更多
关键词 BAICALIN compatibility focal cerebral ischemia/reperfusion gene network jasminoidin traditional Chinese medicine
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Surface Nanocrystallization (SNC) of Metallic Materials-Presentation of the Concept behind a New Approach 被引量:301
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作者 Lu, K Lu, J 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 1999年第3期193-197,共5页
In this paper, a concept of surface nanocrystallization (SNC) of metallic materials is introduced. Three types of SNC processes are classified. Different SNC mechanisms and possible techniques for SNC are discussed wi... In this paper, a concept of surface nanocrystallization (SNC) of metallic materials is introduced. Three types of SNC processes are classified. Different SNC mechanisms and possible techniques for SNC are discussed with emphasis on mechanically induced surface self-nanocrystallization. Further development and prospects are addressed with respect to the properties and behaviors of the materials with a nanocrystalline surface. Enhancement of the behavior of the engineering materials by means of the SNC technology and its industrial application possibilities are analyzed. 展开更多
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Palm Oil Production in Malaysia: An Analytical Systems Model for Balancing Economic Prosperity, Forest Conservation and Social Welfare 被引量:1
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作者 Nickson E. Otieno Xeuping Dai +4 位作者 Daniele De Barba Abbassi Bahman Elise Smedbol Marouan Rajeb Lise Jaton 《Agricultural Sciences》 2016年第2期55-69,共15页
Since the late 1950’s, the Malaysian human population has nearly quadrupled, increasing pressure on natural resource exploitation to meet domestic needs and to earn foreign exchange from exports. Global demand for Ma... Since the late 1950’s, the Malaysian human population has nearly quadrupled, increasing pressure on natural resource exploitation to meet domestic needs and to earn foreign exchange from exports. Global demand for Malaysian palm oil in particular had steeply increased since the mid-1970s and by 2013, the commodity was the leading foreign exchange earner. To fulfill and sustain this demand, the country’s economy has steadily shifted bias towards production and associated value addition of palm oil products for export. However, as a consequence, many of Malaysia’s natural tropical forests have been converted to palm oil farming resulting in loss of approximately 10,000 km2 of forest cover over the past twenty-five years, and biodiversity has been displaced or lost. To provide a deeper insight into the interplay amongst key interrelated environmental and socio-economic variables, and a forecast of possible future balance, we used a systems dynamism modeling tool, STELLAR (structural thinking, experiential learning laboratory with animation), to simulate and project how Malaysia could achieve a medium-term sustainable balance or optimization between palm oil production and forest conservation without compromising on human social welfare. The model consisted of four main modules (environmental, economic, social development and human welfare) each with component parameters, and interconnected by input and output loops. Model calibrations, testing and preruns involved existing official 30-year time-series datasets. Subsequently, four scenarios: Environmental conservation;Economic growth under increased global palm oil demand;Economy decline under decreased palm oil demand;and Control condition with little or no change, were selected for simulated projections of future possibilities. Simulation results showed that scenarios and variable interactions that reduce environmental damage would offer the best chance for optimizing the palm oil economy while also minimizing forest loss and promoting citizen social welfare. 展开更多
关键词 Palm Oil Systems Modeling Sustainable Development CONSERVATION MALAYSIA
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A novel carbazole-based fluorescent probe:3,6-Bis-[(N-ethylcarbazole-3-y1)-propene-1-keto]-N-ethylcarbazole
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作者 Hao, Li Ling Li, Jun Fen +4 位作者 Lin, Pei Hua Dong, Rui Feng Li, Du Xin Shuang, Shao Min Dong, Chuan 《Chinese Chemical Letters》 SCIE CAS CSCD 2010年第1期9-12,共4页
关键词 CARBAZOLE Fluorescent probe Intramolecular charge transfer Synthesis
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Interaction between a novel intramolecular charge transfer fluorescent probe PFEP and human serum albumin
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作者 Ju, Dong Song, Sheng Mei +2 位作者 Wu, Yan Bo Shuang, Shao Min Dong, Chuan 《Chinese Chemical Letters》 SCIE CAS CSCD 2010年第4期480-483,共4页
The interaction mechanism between human serum albumin(HSA) and 1-phenyl-3(fluorenone-2-yl)-5-(9-ethylcarbazole-3-yl)-2- pyrazoline(PFEP) was investigated by fluorescence and absorption titration techniques in combinat... The interaction mechanism between human serum albumin(HSA) and 1-phenyl-3(fluorenone-2-yl)-5-(9-ethylcarbazole-3-yl)-2- pyrazoline(PFEP) was investigated by fluorescence and absorption titration techniques in combination with molecular modeling method.Stern-Volmer plots at different temperatures proved that PFEP could quench the intrinsic fluorescence of HSA attributed to a static quenching procedure.The association constants were calculated in the range of 1×10~5-8×10~5mol^(-1) at different pH conditions,a... 展开更多
关键词 Fluorescent probe Human serum albumin ICT
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