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71.
72.
Fibronectin (Fn) has been shown to play an important role in wound healing because it appears to be the stimulus for migration of fibroblasts and epidermal cells. The purpose of this study was to investigate whether topical application of plasma Fn (pFn) improves healing of full-thickness skin wounds in rats. A round section of full-thickness skin (diameter of approximately 15 mm) was resected in rats. Animals were then divided into two groups, and wounds were treated topically with a single application of human plasma albumin (control group) or human pFn (FN group). Wound closure rate, hydroxyproline concentration, and histologic features (immunohistochemical staining) were evaluated. The FN group had a significantly higher wound closure rate and hydroxyproline level in the skin than the control group. Histologic analysis of macrophage and fibroblast migration, collagen regeneration, and epithelialization were significantly increased in the FN group compared with the control group. A single topical application of pFn increased the migration of macrophages, myofibroblasts, and fibroblasts. Moreover, further release of transforming growth factor-beta1 from activated fibroblasts, keratinocytes, and epithelial cells may also contribute to the beneficial effect of pFn on wound healing.  相似文献   
73.
Fusarium head blight (FHB) and Fusarium seedling blight (FSB) of wheat, caused by Fusarium pathogens, are devastating diseases worldwide. We report the expression of RNA interference (RNAi) sequences derived from an essential Fusarium graminearum (Fg) virulence gene, chitin synthase (Chs) 3b, as a method to enhance resistance of wheat plants to fungal pathogens. Deletion of Chs3b was lethal to Fg; disruption of the other Chs gene family members generated knockout mutants with diverse impacts on Fg. Comparative expression analyses revealed that among the Chs gene family members, Chs3b had the highest expression levels during Fg colonization of wheat. Three hairpin RNAi constructs corresponding to the different regions of Chs3b were found to silence Chs3b in transgenic Fg strains. Co‐expression of these three RNAi constructs in two independent elite wheat cultivar transgenic lines conferred high levels of stable, consistent resistance (combined type I and II resistance) to both FHB and FSB throughout the T3 to T5 generations. Confocal microscopy revealed profoundly restricted mycelia in Fg‐infected transgenic wheat plants. Presence of the three specific short interfering RNAs in transgenic wheat plants was confirmed by Northern blotting, and these RNAs efficiently down‐regulated Chs3b in the colonizing Fusarium pathogens on wheat seedlings and spikes. Our results demonstrate that host‐induced gene silencing of an essential fungal chitin synthase gene is an effective strategy for enhancing resistance in crop plants under field test conditions.  相似文献   
74.

Background

Root system architecture is important for water acquisition and nutrient acquisition for all crops. In soybean breeding programs, wild soybean alleles have been used successfully to enhance yield and seed composition traits, but have never been investigated to improve root system architecture. Therefore, in this study, high-density single-feature polymorphic markers and simple sequence repeats were used to map quantitative trait loci (QTLs) governing root system architecture in an inter-specific soybean mapping population developed from a cross between Glycine max and Glycine soja.

Results

Wild and cultivated soybean both contributed alleles towards significant additive large effect QTLs on chromosome 6 and 7 for a longer total root length and root distribution, respectively. Epistatic effect QTLs were also identified for taproot length, average diameter, and root distribution. These root traits will influence the water and nutrient uptake in soybean. Two cell division-related genes (D type cyclin and auxin efflux carrier protein) with insertion/deletion variations might contribute to the shorter root phenotypes observed in G. soja compared with cultivated soybean. Based on the location of the QTLs and sequence information from a second G. soja accession, three genes (slow anion channel associated 1 like, Auxin responsive NEDD8-activating complex and peroxidase), each with a non-synonymous single nucleotide polymorphism mutation were identified, which may also contribute to changes in root architecture in the cultivated soybean. In addition, Apoptosis inhibitor 5-like on chromosome 7 and slow anion channel associated 1-like on chromosome 15 had epistatic interactions for taproot length QTLs in soybean.

Conclusion

Rare alleles from a G. soja accession are expected to enhance our understanding of the genetic components involved in root architecture traits, and could be combined to improve root system and drought adaptation in soybean.

Electronic supplementary material

The online version of this article (doi:10.1186/s12864-015-1334-6) contains supplementary material, which is available to authorized users.  相似文献   
75.

Background

Beta (β)-human chorionic gonadotropin (β-HCG) is used to confirm the diagnosis and plan treatment of intracranial germinomas. However, the cutoff values of serum β-HCG in diagnosis of intracranial germinomas reported in the literature are inconsistent. To establish an appropriate cutoff value of serum β-HCG for diagnosis of intracranial germinomas, we retrospectively reviewed the records of intracranial tumor patients who received serum β-HCG and α-fetoprotein (AFP) tests for diagnostic purposes at our hospital from 2005 to 2014.

Methods

A total of 93 intracranial germinomas and 289 intracranial non-germ cell tumors were included in this study. Receiver operating characteristic (ROC) analysis was used to evaluate the sensitivity and specificity of 3 cutoffs (0.1, 0.4, and 0.5 mIU/mL) for diagnosing intracranial germinomas. The serum β-HCG level of intracranial germinoma patients was further analyzed to investigate the effect of metastasis status and tumor location on serum β-HCG level.

Results

The area under the ROC curve was 0.81 (P < .001), suggesting β-HCG is an effective marker. Of the 3 cutoff values, 0.1 mIU/mL possessed a highest sensitivity (66.67%) and good specificity (91%). Although there was no β-HCG level difference between metastatic and non-metastatic intracranial germinoma patients, the diagnostic rate of metastatic neurohypophyseal germinomas was significantly higher than that of its non-metastatic counterpart (P < .05), implying that the location of the germinoma might need to be considered when β-HCG is used as a marker to predict metastasis.

Conclusions

Determining an optimal cutoff of serum β-HCG is helpful for assisting the diagnosis of intracranial germinoma.  相似文献   
76.
猪瘟病毒强弱毒株和野毒株E2全基因序列测定及比较分析   总被引:15,自引:0,他引:15  
为了比较猪瘟病毒 (HCV)野毒株、疫苗株及标准株之间E2基因抗原区域的差异 ,采用RT PCR扩增了HCV石门株、兔化弱毒疫苗株、野毒 0 3及 0 7株的囊膜糖蛋白E2 (gp55)全基因的cDNA片段 ,分别克隆于pGEM T载体中并对其进行了核苷酸序列测定及氨基酸序列的推导 ,同时进行了同源性比较及E2结构与功能的分析。所测 4株HCVE2基因的长度均为1 2 73bp,所编码的氨基酸序列均包括部分信号肽序列和完整的跨膜区序列 ,共由 381个氨基酸组成 ;4个毒株E2蛋白N末端的 683位至 690位信号肽序列 (WLLLVTGA)和C末端 1 0 30~1 0 63位跨膜区均为保守序列 ,而且具疏水性 ;N末端抗原功能区中 ,4个E2蛋白与其它所比较序列在位于第 753位至 759位氨基酸处 ,均有一段保守序列RYLASLH ,无一氨基酸发生变异 ,为亲水性 ,在整个E2蛋白抗原谱中抗原性峰值为最高 ,推测对抗原性产生起重要作用 ;4个E2蛋白的氨基酸序列中均含有 1 5个半胱氨酸 (Cys)残基 ,其数量及位置与国外五株HCV(Brescia ,C ,Alfort.ALD和GPE)完全一致。表明…  相似文献   
77.
采用光谱法和胰酯酶分解法对大果木姜子油酯中分得的结晶C—I组成进行了分析,结果表明C—I是由11种甘油三酯组成。其中2-位为月硅酸的甘油三酯占91.80%,1,3-位脂肪酸主要为癸酸和月桂酸,甘油三酯的组成中,CLC占62.24%,LLC占24.50%。  相似文献   
78.
The extraocular muscle (EOM) suffers much less injury from Duchenne muscular dystrophy (DMD) than other skeletal muscles such as diaphragm and gastrocnemius. The present study was undertaken to test the hypothesis that differential expression of regulatory proteins between the EOM and other skeletal muscles is responsible for the observed difference in the sensitivity to DMD-associated damage. Protein expression in the tissue samples obtained from EOM, diaphragm or gastrocnemius of C57BL/6 mice was analyzed by two-dimensional gel electrophoresis and mass spectrometry. There were 35 proteins that were identified to be differentially expressed among different skeletal muscle tissues. Among the 35 proteins, a fast skeletal muscle isoform myosin light chain 1 (MLC1f) protein was further studied in relation to muscle cell proliferation. The EOM-derived myoblasts had much lower levels of MLC1f and higher rate of cell proliferation in contrast to the myoblasts derived from diaphragm or gastrocnemius, which displayed a higher expression of MLC1f along with a slow proliferation. Deletion of MLC1f using siRNA targeting MLC1f resulted in an increased rate of cell proliferation in the myoblasts. Cell cycle analysis revealed that MLC1f inhibited the transition of the cell cycle from the G1 to the S phase. Therefore, the present study demonstrates that MLC1f may negatively regulate proliferation of myoblasts through inhibition of the transition from the G1 to the S phase of the cell cycle. Low levels of MLC1f in myoblasts of EOM may ensure cell proliferation and enhance the repair process for EOM under the DMD disease condition, thus making EOM suffer less injury from DMD.  相似文献   
79.
80.
Jiang D  Ying W  Lu Y  Wan J  Zhai Y  Liu W  Zhu Y  Qiu Z  Qian X  He F 《Proteomics》2003,3(5):724-737
Very little is currently known about mechanisms underlying cancer metastasis. In the present study, metastasis-associated proteomes were separated and identified by comparative proteomic analysis, and the metastasis-related function of candidate protein interleukin-18 (IL-18) was further elucidated. First, a pair of highly and poorly metastatic sublines (termed PLA801D and PLA801C, respectively), originating from the same parental PLA801 cell line, was identified by spontaneous tumorigenicity and metastasis in vivo and characterized by metastatic phenotypes analysis in vitro. Subsequently, a proteomic approach was used to compare the protein expression profiles between PLA801C and PLA801D sublines. Eleven proteins were identified and further verified by one-dimensional Western blotting, Northern blot and/or semiquantitative reverse transciptase polymerase chain reaction analysis. Compared with those in poorly metastatic PLA801C subline, cytokeratin 18, tissue transglutaminase, Rho GDP-dissociation inhibitor 1, tropomyosin, fibroblast type, IL-18 and annexin I were significantly up-regulated, while protein disulfide isomerase, heat shock protein 60, peroxiredoxin 1, chlorine intracellular channel protein 1 (CLI1) and creatine kinase, B chain were significantly down-regulated in the highly metastatic PLA801D subline. Intriguingly, all the identified candidate proteins except for CLI1 have been shown to be somehow associated with distinct aspects of tumor metastasis such as cell growth, motility, invasion, adhesion, apoptosis and tumor immunity, etc. Considering that IL-18 was present in highly metastatic PLA801D but absent in poorly metastatic PLA801C, the association of IL-18 with metastasis was further elucidated by introducing IL-18 sense/IL-18 antisense into PLA801C/PLA801D sublines simultaneously. The results demonstrated that ectopically expressed IL-18 promoted cell motility in vitro and down-regulated E-cadherin expression of PLA801C transfectants, while IL-18 antisense remarkably decreased cell invasion potency in vitro and notably increased E-cadherin expression of PLA801D transfectants, indicating that IL-18 might play a role in metastasis by inhibiting E-cadherin expression.  相似文献   
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