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991.
Brassinosteroid signaling and application in rice 总被引:3,自引:0,他引:3
Combined approaches with genetics, biochemistry, and proteomics studies have greatly advanced our understanding of brassinosteroid (BR) signaling in Arabidopsis. However, in rice, a model plant of monocot and as well an important crop plant, BR signaling is not as well characterized as in Arabidopsis. Recent studies by forward and reverse genetics have identified a number of either conserved or specific components of rice BR signaling pathway, bringing new ideas into BR signaling regulation mechanisms. Genetic manipulation of BR level or BR sensitivity to improve rice yield has established the great significance of BR research achievements. 相似文献
992.
Larvae of the black soldier fly, Hermetia illucens are well‐known fly larvae that inhabit many countries around the world. Antimicrobial agents derived from the larvae may be among the substances that are produced in the body for their survival. This study was carried out to identify the antimicrobial effects of H. illucens larvae that commonly inhabit animal waste and food waste. To evaluate the pharmacological effects of H. illucens larvae extracts, the larvae were extracted by various organic solvents, and their antibacterial effects were determined by antimicrobial methods, such as agar disk diffusion and turbidometric assays. The methanol extracts (ME) indicated antibacterial effects against the proliferation of Klebsiella pneumoniae, Neisseria gonorrhoeae and Shigella sonnei. However, antibacterial effects were not induced in Gram‐positive bacteria such as Bacillus subtilis, Streptococcus mutans and Sarcina lutea. The bacterial growth treated with ME was strongly inhibited from 20 mg/mL in a dose‐dependent manner compared with other extracts, and antibacterial activity gradually decreased after 24 h. Moreover, the minimal inhibitory concentration (MIC) values of ME against Klebsiella pneumoniae, Neisseria gonorrhoeae and Shigella sonnei for 12 h were measured as 44.74 mg/mL, 43.98 mg/mL and 43.96 mg/mL, respectively. These results demonstrate that ME of H. illucens larvae not only has antibacterial activity which strongly inhibits the growth and proliferation of the bacteria but also unique properties which effectively block the viability of the bacteria. 相似文献
993.
ABSTRACT: OBJECTIVE: L1 cell adhesion molecule (L1CAM), as a member of the immunoglobulin superfamily, has recently been observed in a variety of human malignancies. However, no data of L1CAM are available for hepatocellular carcinoma (HCC). The aim of this study was to investigate the expression of L1CAM in HCC and determine its correlation with tumor progression and prognosis. METHODS: One-hundred and thirty HCC patients who had undergone curative liver resection were selected and immunohistochemistry, Western blotting, and quantitative real time polymerase chain reaction (Q-PCR) were performed to analyze L1CAM expression in the respective tumors. RESULTS: Immunohistochemistry, Western blotting, and Q-PCR consistently confirmed the overexpression of L1CAM in HCC tissues compared with their adjacent nonneoplastic tissues at both protein and gene level (both P <0.01). Additionally, the high expression of L1CAM was significantly associated with advanced tumor stage (P = 0.02) and advanced tumor grade (P = 0.03), respectively. Moreover, HCC patients with high L1CAM expression were significantly associated with lower 5-year overall survival (P <0.01) and lower 5-year disease-free survival (P <0.01), respectively. The Cox proportional hazards model further showed that L1CAM over-expression was an independent poor prognostic factor for both 5-year disease-free survival (P = 0.02) and 5-year overall survival (P = 0.008) in HCC. CONCLUSION: Our data suggest for the first time that L1CAM expression in HCC was significantly correlated with the advanced tumor progression and was an independent poor prognostic factor for both overall survival and disease-free survival in patients with HCC.Virtual slidesThe virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/1970024872761542. 相似文献
994.
Xiaodong Guo Lu Xiong Lin Zou Ting Sun Jing Zhang Hanwei Li Ruiyun Peng Jingmin Zhao 《Diagnostic pathology》2012,7(1):1-7
Background
To investigate the expression of Golgi phosphoprotein-3 (GOLPH3) in prostate cancer and determine its prognostic value.Methods
Immunohistochemical staining for GOLPH3 was performed on tissue microarrays of 342 prostate patients. The correlation between GOLPH3 expression with its clinicopathologic factors was also analyzed in order to determine its prognostic significance.Results
GOLPH3 expression of normal prostate tissues, benign prostate hyperplasia, high-grade prostatic intraepithelial neoplasia, and hormone-dependent prostate cancer (HDPC) did not show any statistically significant difference. In contrast, statistically significant difference was reported in moderate/intense GOLPH3 expression in cases diagnosed with HDPC and castration resistant prostate cancer (CRPC) (P < 0.0005). Moderate /intense expression of GOLPH3 was associated with androgen independence (P?=?0.012), higher Gleason score (P?=?0.017), bone metastasis (P?=?0.024), higher baseline prostate-specific antigen (PSA) (P?=?0.038), and higher PSA nadir (P?=?0.032). A significantly negative correlation was found between moderate/intense GOLPH3 expression and disease-free survival (DFS) (HR?=?0.28, P?=?0.012) and overall survival (OS) (HR?=?0.42, P?=?0.027). Univariated analysis indicated that moderate/intense GOLPH3 expression created a significantly prognostic impact in patients with CRPC. On the other hand, multivariate analysis indicated that GOLPH3 was a significantly independent prognostic factor of DFS (P?=?0.027) in all prostate cancer patients.Conclusions
In this study, it was discovered that the overexpression of GOLPH3 is associated with the transition of prostate cancer from hormone sensitive phase to hormone refractory phase. GOLPH3 might be an important prognostic factor of DFS and OS in patients with prostate cancer. In totality, GOLPH3 could be used as a novel candidate in devising a more effective therapeutic strategy to tackle CRPC.Virtual slides
The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/1452541171722856. 相似文献995.
Coleoids are part of the Cephalopoda class, which occupy an important position in most oceans both at an ecological level and at a commercial level. Nevertheless, some coleoid species are difficult to distinguish with traditional morphological identification in cases when specimens are heavily damaged during collection or when closely related taxa are existent. As a useful tool for rapid species assignment, DNA barcoding may offer significant potential for coleoid identification. Here, we used two mitochondrial fragments, cytochrome c oxidase I and the large ribosomal subunit (16S rRNA), to assess whether 34 coleoids accounting for about one-third of the Chinese coleoid fauna could be identified by DNA barcoding technique. The pairwise intra- and interspecific distances were assessed, and relationships among species were estimated by NJ and bayesian analyses. High levels of genetic differentiation within Loliolus beka led to an overlap between intra- and interspecific distances. All remaining species forming well-differentiated clades in the NJ and bayesian trees were identical for both fragments. Loliolus beka possessed two mitochondrial lineages with high levels of intraspecific distances, suggesting the occurrence of cryptic species. This study confirms the efficacy of DNA barcoding for identifying species as well as discovering cryptic diversity of Chinese coleoids. It also lays a foundation for other ecological and biological studies of Coleoidea. 相似文献
996.
997.
Yen-Ching Chen Ping-Keung Yip Yi-Ling Huang Yu Sun Li-Li Wen Yi-Min Chu Ta-Fu Chen 《PloS one》2012,7(12)
Background
Toll like receptor 4 (TLR4) has been related to inflammation and beta-amyloid deposition in Alzheimer''s disease (AD) brain. No study has explored the association between haplotype-tagging single nucleotide polymorphisms (htSNPs) of TLR4 and AD risk previously and ApoE e4 status alone showed low sensitivity in identifying late-onset AD (LOAD) patients.Methods
A total of 269 LOAD patients were recruited from three hospitals in northern Taiwan (2007–2010). Controls (n = 449) were recruited from elderly health checkup and volunteers of the hospital during the same period of time. Five common (frequency≥5%) TLR4 htSNPs were selected to assess the association between TLR4 polymorphisms and the risk of LOAD in the Chinese ethnic population.Results
Homozygosity of TLR4 rs1927907 was significantly associated with an increased risk of LOAD [TT vs. CC: adjusted odds ratio (AOR) = 2.45, 95% confidence interval (CI) = 1.30–4.64]. After stratification, the association increased further in ApoE e4 non-carriers (AOR = 3.07) and in hypertensive patients (AOR = 3.60). Haplotype GACGG was associated with a decreased risk of LOAD (1 vs. 0 copies: AOR = 0.59, 95% CI = 0.36–0.96; 2 vs. 0 copies: AOR = 0.31, 95% CI = 0.14–0.67) in ApoE e4 non-carriers. ApoE e4 status significantly modified this association (p interaction = 0.01). These associations remained significant after correction for multiple tests.Conclusions
Sequence variants of TLR4 were associated with an increased risk of LOAD, especially in ApoE e4 non-carriers and in hypertensive patients. The combination of TLR4 rs1927907 and ApoE e4 significantly increased the screening sensitivity in identifying LOAD patients from 0.4 to 0.7. 相似文献998.
Mark J. Cameron Alyson A. Kelvin Alberto J. Leon Cheryl M. Cameron Longsi Ran Luoling Xu Yong-Kyu Chu Ali Danesh Yuan Fang Qianjun Li Austin Anderson Ronald C. Couch Stephane G. Paquette Ndingsa G. Fomukong Otfried Kistner Manfred Lauchart Thomas Rowe Kevin S. Harrod Colleen B. Jonsson David J. Kelvin 《PloS one》2012,7(9)
In terms of its highly pathogenic nature, there remains a significant need to further define the immune pathology of SARS-coronavirus (SARS-CoV) infection, as well as identify correlates of immunity to help develop vaccines for severe coronaviral infections. Here we use a SARS-CoV infection-reinfection ferret model and a functional genomics approach to gain insight into SARS immunopathogenesis and to identify correlates of immune protection during SARS-CoV-challenge in ferrets previously infected with SARS-CoV or immunized with a SARS virus vaccine. We identified gene expression signatures in the lungs of ferrets associated with primary immune responses to SARS-CoV infection and in ferrets that received an identical second inoculum. Acute SARS-CoV infection prompted coordinated innate immune responses that were dominated by antiviral IFN response gene (IRG) expression. Reinfected ferrets, however, lacked the integrated expression of IRGs that was prevalent during acute infection. The expression of specific IRGs was also absent upon challenge in ferrets immunized with an inactivated, Al(OH)3-adjuvanted whole virus SARS vaccine candidate that protected them against SARS-CoV infection in the lungs. Lack of IFN-mediated immune enhancement in infected ferrets that were previously inoculated with, or vaccinated against, SARS-CoV revealed 9 IRG correlates of protective immunity. This data provides insight into the molecular pathogenesis of SARS-CoV and SARS-like-CoV infections and is an important resource for the development of CoV antiviral therapeutics and vaccines. 相似文献
999.
The crystal structure of the yeast SLN1 response regulator (RR) domain bound to both a phosphoryl analog [beryllium fluoride (BeF3 −)] and Mg2 +, in complex with its downstream phosphorelay signaling partner YPD1, has been determined at a resolution of 1.70 Å. Comparisons between the BeF3 −-activated complex and the unliganded (or apo) complex determined previously reveal modest but important differences. The SLN1-R1·Mg2 +·BeF3 − structure from the complex provides evidence for the first time that the mechanism of phosphorylation-induced activation is highly conserved between bacterial RR domains and this example from a eukaryotic organism. Residues in and around the active site undergo slight rearrangements in order to form bonds with the essential divalent cation and fluorine atoms of BeF3 −. Two conserved switch-like residues (Thr1173 and Phe1192) occupy distinctly different positions in the apo versus BeF3 −-bound structures, consistent with the “Y-T” coupling mechanism proposed for the activation of CheY and other bacterial RRs. Several loop regions and the α4-β5-α5 surface of the SLN1-R1 domain undergo subtle conformational changes (∼ 1-3 Å displacements relative to the apo structure) that lead to significant changes in terms of contacts that are formed with YPD1. Detailed structural comparisons of protein-protein interactions in the apo and BeF3 −-bound complexes suggest at least a two-state equilibrium model for the formation of a transient encounter complex, in which phosphorylation of the RR promotes the formation of a phosphotransfer-competent complex. In the BeF3 −-activated complex, the position of His64 from YPD1 needs to be within ideal distance of and in near-linear geometry with Asp1144 from the SLN1-R1 domain for phosphotransfer to occur. The ground-state structure presented here suggests that phosphoryl transfer will likely proceed through an associative mechanism involving the formation of a pentacoordinate phosphorus intermediate. 相似文献
1000.