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101.
102.
Kun Wang Qiubo Huang Guangqiang Zhao Jiapeng Yang Kaiyun Yang Yunchao Huang 《Journal of cellular biochemistry》2019,120(9):14804-14812
Plasma pro-surfactant protein B (pro-SFTPB) and N1,N12-diacetylspermine (DAS) can be used as markers for the diagnosis of non–small-cell lung carcinoma (NSCLC). Whether the genetic diversity affects the application value of Pro-SFTPB and DAS as a diagnostic marker for NSCLC is still unknown. This study aims to explore the relationship between SFTPB rs7316, rs9752 and PAOX rs1046175 gene polymorphisms and the diagnostic value of plasma Pro-SFTPB and DAS in patients with Chinese Han lung cancer. SFTPB rs7316, rs9752 and PAOX rs1046175 genotypes were analyzed by direct sequencing in 425 patients with NSCLC and 425 controls, and the levels of Pro-SFTPB and DAS in plasma were determined by enzyme-linked immunosorbent assay (ELISA). The area under the curve (AUC) of the SFTPB rs7316 locus TT genotype for the diagnosis of NSCLC was 0.758, and the AUC of the TC/CC genotype for the diagnosis of NSCLC was 0.872. The AUC of the SFTPB rs9752 locus GG genotype for the diagnosis of NSCLC was 0.935, and the AUC of the GC/CC genotype for the diagnosis of NSCLC was 0.648. The AUC of the PAOX rs1046175 locus GG for the diagnosis of NSCLC was 0.669, and the AUC of the GC/CC genotype for the diagnosis of NSCLC was 0.749. In conclusion, SFTPB rs7316, rs9752, and PAOX rs1046175 gene polymorphisms affect the diagnostic value of plasma Pro-SFTPB and DAS in patients with Chinese Han NSCLC. 相似文献
103.
Arvid WA Kamps Dick Hendriks Jan W Smit Edo Vellenga 《Cancer immunology, immunotherapy : CII》1999,16(1):46-52
The present study focused on whether it is possible to expand monocytic cells from CD34+ progenitor cells by using macrophage colony-stimulating factor (M-CSF) in the absence and presence of mast cell growth factor
(MGF) and IL-6. It was demonstrated that CD34+ cells differentiate without expansion to functional mature monocytic cells in the presence of M-CSF or combinations of M-CSF
plus IL-6 and MGF. A different response pattern was observed for the number of clonogenic cells. The addition of IL-6 or both
IL-6 and MGF to M-CSF containing cultures resulted in significant higher numbers of colony-forming unit-macrophage (CFU-M)
as tested in clonogenic and3H-thymidine assays. Furthermore, M-CSF plus both IL-6 and MGF appeared to be the most potent combination to preserve the monocytic
precursor in cell suspension culture assays. These results indicate that IL-6 and MGF in conjunction with M-CSF affect CD34+ cells especially at precursor level without distinct effect on the more mature stages. Secondly we studied whether M-CSF
is only critical for the monocytic lineage or also affects dendritic cell (DC) development. Indeed, we were able to culture
CD83+ DC from CD34+ progenitor cells in the presence of M-CSF in conjunction with TNF-α, IL-4, and MGF although their absolute number is almost
threefold lower than the number of CD83+ cells yielded from GM-CSF plus TNF-α, IL-4, and MGF stimulated CD34+ cells. 相似文献
104.
A gas chromatographic-electron capture detection (GC-ECD) method for the analysis of deoxynivalenol (DON) in cereals was investigated.
The sample was extracted with a mixture of acetonitrile-water and purified with a MycoSep #225 column. The silylation was
performed with Tri-Sil-TBT reagent, followed by dilution with hexane and a washing step with buffer. By using Tri-Sil-TBT
reagent no double peaks were observed for DON in the gas chromatograms, in comparison with two other silylation reagents TMSI
and Tri-Sil-Z. The use of trichothecolone (TRI) as an internal standard for DON was studied in order to indicate possible
problems in the derivatisation reaction. TRI proved to be a relatively good internal standard for DON in cereal samples, as
well as 1,1-bis-(4-chlorophenyl)-2,2-dichloroethylene (DDE), which was used as a GC standard for ensuring the function of
GC-ECD. During the study, a matrix effect was clearly observed between the cereal matrix-assisted calibration curve and the
calibration curve prepared without cereal matrix. The results of spiked and reference material samples, quantified with the
calibration curve prepared without and with matrix, demonstrated that the matrix affects the results. However, after recovery
correction the results were comparable. The validation results demonstrated that the GC-ECD method for DON analysis in cereals
is sufficiently reliable. 相似文献
105.
106.
107.
The effective population size of Anopheles gambiae in Kenya: implications for population structure 总被引:4,自引:0,他引:4
We estimated current and long-term effective population size (Ne) of two
Anopheles gambiae (savanna cytotype) populations in Kenya. Temporal
variation at nine microsatellite loci in each population sampled 7 and 9
years apart and genetic diversity in each sample were analyzed to answer
the following questions. (1) Do bottlenecks occur in Kenyan populations of
A. gambiae? (2) How variable are different populations with respect to
their current and long-term Ne values? (3) What are the implications of
these results on population structure and history? The estimates of Ne of
Asembo and Jego were 6,359 and 4,258, respectively, and the lower 95%
limits were 2,455 and 1,669, respectively. Thus, despite the typical
observation of low density at the village level during the dry season,
large populations are maintained annually. Large current Ne is consistent
with previous studies showing low differentiation across the continent,
especially under Wright's isolation-by-distance model. Current Ne in Asembo
was 1.5-fold higher than in Jego, but this difference was not significant.
Long-term Ne in Asembo (22,667) was 2.9-fold higher than that in Jego
(7,855) based on the stepwise mutation model. The difference between
populations was significant at both time points regardless of whether
long-term Ne values were calculated based on the stepwise mutation model or
the infinite-alleles model. Heterozygosity in Jego declined significantly
between 1987 (59%) and 1996 (54%), whereas heterozygosity in Asembo was
stable (66%-65%). Despite the relatively high and significant
differentiation between Asembo and Jego (FST = 0.072-0.10, RST = 0.037-
0.038), all alleles in Jego were found in Asembo but not vice versa. All of
these findings suggest that lower Ne in Jego magnifies differentiation
between the two populations. The long-term Ne was biased downward, because
its calculation was based on an upper bound estimate of microsatellite
mutation rate. Ne values based on mtDNA and allozymes were an order of
magnitude higher. Long-term Ne therefore, is probably measured in hundreds
of thousands and hence does not support a recent expansion of this species
from a small population.
相似文献
108.
Excessive tissue iron levels are associated with the increase of oxidative/nitrative stress which contributes to tissue damage that may elevate the risk of diabetes. Therefore, we investigated the effects of iron on diabetes-associated liver injury and whether iron-related tyrosine nitration participated in this process. Rats were randomly divided into four groups: control, iron overload (300 mg/kg iron dextran, i.p.), diabetic (35 mg/kg of streptozotocin i.p. after administration of a high-fat diet) and diabetic simultaneously treated with iron. Iron supplement markedly increased diabetes-mediated liver damage and hepatic dysfunction by increasing liver/body weight ratio, serum levels of aspartate and alanine aminotransferase, and histological examination, which were correlated with elevated levels of lipid peroxidation, protein carbonyls and tyrosine nitration, oxidative metabolism of nitric oxide, and reduced antioxidant capacity. Consequently, the extent of oxidized/nitrated glucokinase was markedly increased in the iron-treated diabetic rats that contribute to a decrease in its expression and activity. Further studies revealed a significant contribution of iron-induced specific glucokinase nitration sites to its inactivation. In conclusion, iron facilitates diabetes-mediated elevation of oxidative/nitrative stress, simultaneously impairs liver GK, and can be a link between enzymatic changes and hepatic dysfunction. These findings may provide new insight on the role of iron in the pathogenesis of diabetes mellitus. 相似文献
109.
喀斯特小流域土壤有机碳空间异质性及储量估算方法 总被引:3,自引:0,他引:3
为了准确估算土壤有机碳储量,利用网格法采集2755个土壤剖面,共计23536个土壤样品,研究了喀斯特小流域土壤有机碳含量分布特征,并以"土壤类型法"为基准,对土壤分布面积、石砾含量、岩石裸露率、土层厚度等指标进行修正,合理的优化了土壤有机碳储量计算公式,探索出一种专属于喀斯特地区土壤有机碳储量的估算方法,结果表明:不同土层深度和土壤类型下土壤有机碳含量存在明显差异,土壤有机碳含量随着土层深度的增加而逐渐减小,不同土属的有机碳含量减小的幅度有所差异,不同坡位和坡向的有机碳含量大小为:阳坡阴坡,坡中上部坡顶坡中坡中下坡坡底,不同土地利用方式下土壤有机碳含量大小顺序为:林地灌草地旱地水田;土壤有机碳含量与坡度、海拔、岩石裸露率均呈极显著正相关关系,与土层厚度、土壤容重呈显著负相关;喀斯特地区土壤异质性较大,不同修正指标对土壤有机碳储量估算的影响程度为:土壤厚度岩石裸露率石砾含量土壤有机碳含量土壤容重;通过修正后的计算公式估算出普定后寨河小流域表层20 cm土壤有机碳密度区间为3.53—5.44 kg/m~2,平均值为:1.24 kg/m~2,100 cm土壤有机碳密度区间为4.44—14.50 kg/m~2,平均值为12.12 kg/m~2,土壤有机碳储量为5.39×10~5t。 相似文献
110.
生物固氮是马尾松林地土壤氮素的重要来源,固氮微生物群落组成和数量的变化对土壤氮素供应和地力维持起重要作用。采用池栽试验,应用荧光定量PCR(聚合酶链式反应,Polymerase Chain Reaction)技术,借助Illumina Miseq高通量测序平台,以nifH基因为标靶,研究四类母岩(变余砂岩、长石石英砂岩、石英砂岩和玄武岩)发育马尾松土壤固氮菌群落结构和丰度的差异及其与土壤化学性质之间的关系。结果表明:(1)玄武岩土壤的有机碳、全氮、碱解氮、微生物量氮、马尾松株高和地径均显著高于其他母岩(P < 0.05)。(2)四类母岩土壤nifH基因丰度差异显著,玄武岩土壤nifH基因丰度分别是变余砂岩、石英砂岩和长石石英砂岩的3.75倍、7.89倍和4.41倍。(3)四类母岩土壤固氮菌群落α多样性指数(丰富度和多样性)差异显著,且玄武岩显著高于其他母岩。四类母岩发育土壤共获得有效序列159231条,分属于6个门、14个纲、41个目、69个科和122个属。门水平上,变形菌门和蓝藻门为主要优势类群。属水平上,慢生根瘤菌属、眉藻属、根瘤菌属和固氮螺菌属为主要优势属。玄武岩土壤变形菌门、慢生根瘤菌属、根瘤菌属和固氮螺菌属相对丰度显著高于其他母岩。层次聚类和非度量多维尺度(NMDS)分析结果表明,石英砂岩和长石石英砂岩土壤固氮菌群落结构相似,玄武岩与其他母岩固氮菌群落结构差异较大。(4)土壤有机碳、全氮、碱解氮和微生物量氮是固氮菌丰度、α多样性及群落结构的主要影响因子。综上,玄武岩土壤肥力高,提高了土壤固氮菌数量和群落多样性,有利于马尾松生长。研究从微生物学角度为马尾松适地造林和氮素调控提供了科学依据。 相似文献