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991.
Is Yield Increase Sufficient to Achieve Food Security in China?   总被引:3,自引:0,他引:3  
Increasing demand for food, driven by unprecedented population growth and increasing consumption, will keep challenging food security in China. Although cereal yields have substantially improved during the last three decades, whether it will keep thriving to meet the increasing demand is not known yet. Thus, an integrated analysis on the trends of crop yield and cultivated area is essential to better understand current state of food security in China, especially on county scale. So far, yield stagnation has extensively dominated the main cereal-growing areas across China. Rice yield is facing the most severe stagnation that 53.9% counties tracked in the study have stagnated significantly, followed by maize (42.4%) and wheat (41.9%). As another important element for production sustainability, but often neglected is the planted area patterns. It has been further demonstrated that the loss in productive arable land for rice and wheat have dramatically increased the pressure on achieving food security. Not only a great deal of the planted areas have stagnated since 1980, but also collapsed. 48.4% and 54.4% of rice- and wheat-growing counties have lost their cropland areas to varying degrees. Besides, 27.6% and 35.8% of them have retrograded below the level of the 1980s. The combined influence (both loss in yield and area) has determined the crop sustainable production in China to be pessimistic for rice and wheat, and consequently no surprise to find that more than half of counties rank a lower level of production sustainability. Therefore, given the potential yield increase in wheat and maize, as well as substantial area loss of rice and wheat, the possible targeted adaptation measures for both yield and cropping area is required at county scale. Moreover, policies on food trade, alongside advocation of low calorie diets, reducing food loss and waste can help to enhance food security.  相似文献   
992.
ObjectiveFew data are available on the potential role of inflammatory mediators and T lymphocytes in persistent organ failure (POF) in acute pancreatitis (AP). We conducted a retrospective study to characterize their role in the progression of POF in AP.MethodsA total of 69 AP patients presented within 24 hours from symptom onset developing organ failure (OF) on admission were included in our study. There were 39 patients suffering from POF and 30 from transient OF (TOF). On the 1st, 3rd and 7th days after admission, blood samples were collected for biochemical concentration monitoring including serum IL-1β, IL-6, TNF-α and high-sensitivity C-reactive protein (hs-CRP). The proportions of peripheral CD4+ and CD8+ T lymphocytes were assessed based on flow cytometry simultaneously.ResultsPatients with POF showed a significantly higher value of IL-1β and hs-CRP on day 7 compared with the group of TOF (P < 0.05). Proportions of CD4+ T cells on days 1, 3, 7 and CD4+ / CD8+ ratio on day 1 were statistically lower in the group of POF patients (P < 0.05). A CD4+ T cell proportion of 30.34% on day 1 predicted POF with an area under the curve (AUC) of 0.798, a sensitivity with 61.54% and specificity with 90.00%, respectively.ConclusionsThe reduction of peripheral blood CD4+ T lymphocytes is associated with POF in AP, and may act as a potential predictor.  相似文献   
993.
The Bcl‐2 family modulates sensitivity to chemotherapy in many cancers, including melanoma, in which the RAS/BRAF/MEK/ERK pathway is constitutively activated. Mcl‐1, a major anti‐apoptotic protein in the Bcl‐2 family, is extensively expressed in melanoma and contributes to melanoma's well‐documented chemoresistance. Here, we provide the first evidence that Mcl‐1 phosphorylation at T163 by ERK1/2 and JNK is associated with the resistance of melanoma cell lines to the existing BH3 mimetics gossypol, S1 and ABT‐737, and a novel anti‐apoptotic mechanism of phosphorylated Mcl‐1 (pMcl‐1) is revealed. pMcl‐1 antagonized the known BH3 mimetics by sequestering pro‐apoptotic proteins that were released from Bcl‐2/Mcl‐1. Furthermore, an anthraquinone BH3 mimetic, compound 6, was identified to be the first small molecule to that induces endogenous apoptosis in melanoma cells by directly binding Bcl‐2, Mcl‐1, and pMcl‐1 and disrupting the heterodimers of these proteins. Although compound 6 induced upregulation of the pro‐apoptotic protein Noxa, its apoptotic induction was independent of Noxa. These data reveal the promising therapeutic potential of targeting pMcl‐1 to treat melanoma. Compound 6 is therefore a potent drug that targets pMcl‐1 in melanoma.  相似文献   
994.
In this work, the interaction of chlortetracycline with bovine serum albumin (BSA) was investigated by fluorescence spectroscopy, circular dichroism (CD) spectroscopy, and molecular docking. Results indicated that chlortetracycline quenches BSA fluorescence mainly by a static quenching mechanism. The quenching constants (KSV) were obtained as 5.64 × 104, 4.49 × 104/, and 3.44 × 104/ M?1 at 283, 295, and 307 K, respectively. The thermodynamic parameters of enthalpy change Δ H°, entropy change Δ S°, and free energy change Δ G° were ?5.12 × 104/ J mol?1, ?97.6 J mol?1 K?1, and ?2.24 × 104/ J mol?1 (295 K), respectively. The association constant (KA) and the number of binding sites (n) were 9.41 × 103/ M?1 and 0.86, respectively. The analysis results suggested that the interaction was spontaneous, and van der Waals force and hydrogen‐bonding interactions played key roles in the reaction process. In addition, CD spectra proved secondary structure alteration of BSA in the presence of chlortetracycline. © 2012 Wiley Periodicals, Inc. J Biochem Mol Toxicol 26:331–336, 2012; View this article online at wileyonlinelibrary.com . DOI 10:1002/jbt.21424  相似文献   
995.
Cytoplasmic axin expression frequently produces punctuate structures in cells, but the nature of axin puncta has not been fully elucidated. In an effort to analyze cytoplasmic axin puncta, we established HeLa cells expressing axin in a doxycycline-inducible manner (HeLa-Axin). We observed that axin accumulated in an aggregate-like pattern in perinuclear areas and appeared to be associated with mitochondria, Golgi apparatus, and endoplasmic reticulum (ER), but not lysosomes. Further biochemical analysis suggested that some part of the cytoplasmic axin pool was associated with mitochondria. In addition, mitochondrial proteins [i.e., cytochrome oxidase IV (CoxIV) and cytochrome c] were slightly higher in HeLa-Axin cells than in HeLa-EV cells, suggesting altered mitochondrial degradation. HeLa-Axin cells were then treated with staurosporine (STS) to determine if the mitochondria-induced apoptosis pathway was altered. Compared to STS-treated control cells (HeLa-EV), HeLa-Axin cells had less STS-induced cytotoxicity and reduced caspase-3 activation and PARP cleavage. Given that mitochondria outer membrane potential was unchanged, HeLa-Axin cells might be relatively resistant to STS-mediated mitochondrial damage. Mitochondria associated with axin aggregates were resistant to detergent-mediated permeabilization. These results suggest that axin forms aggregate-like structures in association with mitochondria, which render mitochondria resistant to STS-induced membrane damage and cytotoxicity.  相似文献   
996.
The threat of a highly pathogenic avian influenza (HPAI) H5N1 virus causing the next pandemic remains a major concern. In this study, we evaluated the immunogenicity and efficacy of an inactivated whole-virus H5N1 pre-pandemic vaccine (MG1109) formulated by Green Cross Co., Ltd containing the hemagglutinin (HA) and neuraminidase (NA) genes of the clade 1 A/Vietnam/1194/04 virus in the backbone of A/Puerto Rico/8/34 (RgVietNam/04xPR8/34). Administration of the MG1109 vaccine (2-doses) in mice and ferrets elicited high HI and SN titers in a dose-dependent manner against the homologous (RgVietNam/04xPR8/34) and various heterologous H5N1 strains, (RgKor/W149/06xPR8/34, RgCambodia/04xPR8/34, RgGuangxi/05xPR8/34), including a heterosubtypic H5N2 (A/Aquatic bird/orea/W81/05) virus. However, efficient cross-reactivity was not observed against heterosubtypic H9N2 (A/Ck/Korea/H0802/08) and H1N1 (PR/8/34) viruses. Mice immunized with 1.9 μg HA/dose of MG1109 were completely protected from lethal challenge with heterologous wild-type HPAI H5N1 A/EM/Korea/W149/06 (clade 2.2) and mouse-adapted H5N2 viruses. Furthermore, ferrets administered at least 3.8 μg HA/dose efficiently suppressed virus growth in the upper respiratory tract and lungs. Vaccinated mice and ferrets also demonstrated attenuation of clinical disease signs and limited virus spread to other organs. Thus, this vaccine provided immunogenic responses in mouse and ferret models even against challenge with heterologous HPAI H5N1 and H5N2 viruses. Since the specific strain of HPAI H5N1 virus that would potentially cause the next outbreak is unknown, pre-pandemic vaccine preparation that could provide cross-protection against various H5 strains could be a useful approach in the selection of promising candidate vaccines in the future.  相似文献   
997.
The aim of this study was to determine whether the Glutathione S-transferase M1 (GSTM1) and P1 (GSTP1) polymorphisms confer susceptibility to rheumatoid arthritis (RA). Meta-analysis was performed on the associations between the GSTM1 and GSTP1 null genotypes and RA, and on the association between smoking or seropositive status and the GSTM1 null genotype in RA patients. Twelve studies involving 3,990 RA patients and 2,815 controls were included in the meta-analysis. All 12 studies examined the GSTM1 polymorphism and three the GSTP1 polymorphism. Meta-analysis of GSTM1 null polymorphism in 2,291 RA and 2,713 control subjects revealed no association between RA and the GSTM1 null genotype (OR?=?1.139, 95?% CI?=?0.914–1.419, p?=?0.246). Stratification by ethnicity indicated no association between the GSTM1 null genotype and RA in Asians or Europeans (OR?=?1.245, 95?% CI?=?0.729–2.124, p?=?0.422; OR?=?1.023, 95?% CI?=?0.794–1.318, p?=?0.863). Furthermore, there was no association between smoking and the GSTM1 null genotype (OR?=?0.943, 95?% CI?=?0.734–1.210, p?=?0.642). In addition, no association was found between seropositive status including anti-CCP (anti-citrullinated antibody) and/or RF (rheumatoid factor) and the GSTM1 null genotype. Meta-analysis of 915 RA and 1,082 controls revealed no association between RA and the GSTP1 null genotype (OR?=?0.965, 95?% CI?=?0.802–1.161, p?=?0.704). Furthermore, stratification by ethnicity indicated no association between the GSTP1 null genotype and RA in Europeans (OR?=?0.794, 95?% CI?=?0.594–1.061, p?=?0.119). This meta-analysis suggests that the GSTM1 and GSTP1 polymorphisms are not associated with the risk of RA. However, due to the small number of studies included and our inability to perform subgroup analysis by environmental factors, further studies are required to explore the roles played by GSTM1 and GSTP1 polymorphisms in the pathogenesis of RA.  相似文献   
998.
Primary biliary cirrhosis (PBC) is a chronic cholestatic liver disease of unknown etiology and is considered to be an autoimmune disease. Autoantibodies are important tools for accurate diagnosis of PBC. Here, we employed serum profiling analysis using a human proteome microarray composed of about 17,000 full-length unique proteins and identified 23 proteins that correlated with PBC. To validate these results, we fabricated a PBC-focused microarray with 21 of these newly identified candidates and nine additional known PBC antigens. By screening the PBC microarrays with additional cohorts of 191 PBC patients and 321 controls (43 autoimmune hepatitis, 55 hepatitis B virus, 31 hepatitis C virus, 48 rheumatoid arthritis, 45 systematic lupus erythematosus, 49 systemic sclerosis, and 50 healthy), six proteins were confirmed as novel PBC autoantigens with high sensitivities and specificities, including hexokinase-1 (isoforms I and II), Kelch-like protein 7, Kelch-like protein 12, zinc finger and BTB domain-containing protein 2, and eukaryotic translation initiation factor 2C, subunit 1. To facilitate clinical diagnosis, we developed ELISA for Kelch-like protein 12 and zinc finger and BTB domain-containing protein 2 and tested large cohorts (297 PBC and 637 control sera) to confirm the sensitivities and specificities observed in the microarray-based assays. In conclusion, our research showed that a strategy using high content protein microarray combined with a smaller but more focused protein microarray can effectively identify and validate novel PBC-specific autoantigens and has the capacity to be translated to clinical diagnosis by means of an ELISA-based method.  相似文献   
999.
To provide insights into the molecular mechanisms underlying diabetes mellitus, we performed a proteomic study on two diabetic animal models, streptozotocin (STZ)-induced diabetic rats (T1DM) and genetically diabetic (C57BL/6J ob/ob) mice (T2DM). To better understand the recovery process of those diabetic rodents, we examined the effect of hypoglycemic dipeptide Cyclo (His-Pro) (CHP) treatment on the differential expression of pancreatic proteins in both animal models. Oral administration of CHP had an excellent hypoglycemic effect in both animal models, lowering the average plasma glucose level by over 50%. Pancreatic proteins were separated by two-dimensional gel electrophoresis (2-DE) and identified by MALDI-TOF mass spectrometry. This study allowed, for the first time, the identification of 34 proteins that are related to diabetes and potential targets of CHP, a potent anti-diabetic agent for both T1DM and T2DM. The alterations in the expression of these proteins could indicate a tendency for diabetic animals to overcome their diabetic state. These proteins are involved in cellular functions such as metabolism, cellular structure, oxidative stress, as well as signal and energy transduction. Some have already been linked to diabetes, suggesting that the newly identified proteins might also be significant in the etiology of this pathology and should be further investigated. Furthermore, CHP has emerged as a potent tool for both the treatment and study of the molecular mechanisms underlying diabetes. Thus, the findings presented here provide new insights into the study and potential treatment of this pathology.  相似文献   
1000.
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