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991.
Supercritical carbon dioxide (SC-CO2) was used to inactivate fungal spores of Alternaria brassicicola. The inactivation conditions were optimized using response surface methodology (RSM). When the SC-CO2-entrainer (ethanol) system was applied to fungal spores, the treatment time required for the complete inactivation of fungal spores was substantially reduced. 相似文献
992.
Hyung‐Doo Park Eun‐Suk Kang Jong‐Won Kim Kyu‐Taek Lee Kwang Hyuck Lee Young Suk Park Joon‐Oh Park Jeeyun Lee Jin Seok Heo Seong Ho Choi Dong Wook Choi Seonwoo Kim Jong Kyun Lee Soo‐Youn Lee 《Proteomics》2012,12(23-24):3590-3597
Pancreatic ductal adenocarcinoma (PDAC) accounts for 95% of pancreatic cancers. CA19‐9 is not widely used for screening PDAC due to its low sensitivity. Here, we studied the clinical usefulness of cathepsin D, matrix metalloproteinases (MMPs), and tissue inhibitors of MMPs (TIMPs) for screening patients with PDAC. A total of 248 patients with PDAC and 216 control subjects were recruited (109 PDAC patients and 70 controls in the training set and 139 PDAC patients and 146 controls in the validation set). We measured serum levels of cathepsin D, TIMPs (?1, ?3, and ?4), and MMPs (?1, ?7, ?8, and ?9) using Fluorokine MAP multiplex kits. The concentrations of cathepsin D and MMP‐7 were significantly higher in PDAC subjects than control subjects. In the training set, the diagnostic sensitivity and AUC of the panel of CA19‐9, cathepsin D, and MMP‐7 for PDAC were increased to 88% and 0.900, compared to 74% and 0.835 of CA19‐9 single marker at 80% specificity. The sensitivity using cut‐off value of biomarker panel was significantly increased in the validation set as well as training set. Our findings indicate that a serum biomarker panel consisting of CA19‐9, cathepsin D, and MMP‐7 may provide the most effective screening test currently feasible for PDAC. 相似文献
993.
GalaxyTBM: template-based modeling by building a reliable core and refining unreliable local regions
ABSTRACT: BACKGROUND: Protein structures can be reliably predicted by template-based modeling (TBM) when experimental structures of homologous proteins are available. However, it is challenging to obtain structures more accurate than the single best templates by either combining information from multiple templates or by modeling regions that vary among templates or are not covered by any templates. RESULTS: We introduce GalaxyTBM, a new TBM method in which the more reliable core region is modeled first from multiple templates and less reliable, variable local regions, such as loops or termini, are then detected and re-modeled by an ab initio method. This TBM method is based on "Seok-server," which was tested in CASP9 and assessed to be amongst the top TBM servers. The accuracy of the initial core modeling is enhanced by focusing on more conserved regions in the multiple-template selection and multiple sequence alignment stages. Additional improvement is achieved by ab initio modeling of up to 3 unreliable local regions in the fixed framework of the core structure. Overall, GalaxyTBM reproduced the performance of Seok-server, with GalaxyTBM and Seok-server resulting in average GDT-TS of 68.1 and 68.4, respectively, when tested on 68 single-domain CASP9 TBM targets. For application to multi-domain proteins, GalaxyTBM must be combined with domain-splitting methods. CONCLUSION: Application of GalaxyTBM to CASP9 targets demonstrates that accurate protein structure prediction is possible by use of a multiple-template-based approach, and ab initio modeling of variable regions can further enhance the model quality. 相似文献
994.
Witte AB Timmer CM Gam JJ Choi SK Banaszak Holl MM Orr BG Baker JR Sinniah K 《Biomacromolecules》2012,13(2):507-516
The present study describes the biophysical characterization of generation-five poly(amidoamine) (PAMAM) dendrimers conjugated with riboflavin (RF) as a cancer-targeting platform. Two new series of dendrimers were designed, each presenting the riboflavin ligand attached at a different site (isoalloxazine at N-3 and d-ribose at N-10) and at varying ligand valency. Isothermal titration calorimetry (ITC) and differential scanning calorimetry (DSC) were used to determine the binding activity for riboflavin binding protein (RfBP) in a cell-free solution. The ITC data shows dendrimer conjugates have K(D) values of ≥ 465 nM on a riboflavin basis, an affinity ~93-fold lower than that of free riboflavin. The N-3 series showed greater binding affinity in comparison with the N-10 series. Notably, the affinity is inversely correlated with ligand valency. These findings are also corroborated by DSC, where greater protein-conjugate stability is achieved with the N-3 series and at lower ligand valency. 相似文献
995.
Zhang T Li Y Park KA Byun HS Won M Jeon J Lee Y Seok JH Choi SW Lee SH Man Kim J Lee JH Son CG Lee ZW Shen HM Hur GM 《Autophagy》2012,8(4):559-576
Targeted disruption of STAT3 function has proven to be a useful cancer therapeutic approach by inducing apoptotic cell death. Cucurbitacin is currently under development as a small molecule of STAT3 inhibitor to trigger cell death in many cancers. Here, we systematically studied the molecular mechanisms underlying cucurbitacin-induced cell death, in particular the involvement of autophagy. Treatment with cucurbitacin resulted in non-apoptotic cell death in a caspase-independent manner. Notably, cucurbitacin enhanced excessive conversion of lipidated LC3 (LC3-II) and accumulation of autophagosomes in many cell types. Such autophagy and cell death induced by cucurbitacin were independent of its ability to inhibit STAT3 function, but mainly mediated by enhanced production of mitochondrial-derived reactive oxygen species (ROS), and subsequently activation of extracellular signal-regulated kinase (ERK) and c-jun NH2-terminal kinase (JNK). Interestingly, both the autophagy inhibitor wortmannin and knockdown of Atg5 or Beclin 1 failed to rescue the cells from cucurbitacin-induced cell death, as suppression of autophagy induced the mode of cell death to shift from autophagic cell death to caspase-dependent apoptosis. Thus the present study provides new insights into the molecular mechanisms underlying cucurbitacin-mediated cell death and supports cucurbitacin as a potential anti-cancer drug through modulating the balance between autophagic and apoptotic modes of cell death. 相似文献
996.
Background
Dengue is the most prevalent mosquito borne infection worldwide. Vertical transmissions after maternal dengue infection to the fetus and pregnancy losses in relation to dengue illness have been reported. The relationship of dengue to miscarriage is not known.Method
We aimed to establish the relationship of recent dengue infection and miscarriage. Women who presented with miscarriage (up to 22 weeks gestation) to our hospital were approached to participate in the study. For each case of miscarriage, we recruited 3 controls with viable pregnancies at a similar gestation. A brief questionnaire on recent febrile illness and prior dengue infection was answered. Blood was drawn from participants, processed and the frozen serum was stored. Stored sera were thawed and then tested in batches with dengue specific IgM capture ELISA, dengue non-structural protein 1 (NS1) antigen and dengue specific IgG ELISA tests. Controls remained in the analysis if their pregnancies continued beyond 22 weeks gestation. Tests were run on 116 case and 341 control sera. One case (a misdiagnosed viable early pregnancy) plus 45 controls (39 lost to follow up and six subsequent late miscarriages) were excluded from analysis.Findings
Dengue specific IgM or dengue NS1 antigen (indicating recent dengue infection) was positive in 6/115 (5·2%) cases and 5/296 (1·7%) controls RR 3·1 (95% CI 1·0–10) P = 0·047. Maternal age, gestational age, parity and ethnicity were dissimilar between cases and controls. After adjustments for these factors, recent dengue infection remained significantly more frequently detected in cases than controls (AOR 4·2 95% CI 1·2–14 P = 0·023).Interpretation
Recent dengue infections were more frequently detected in women presenting with miscarriage than in controls whose pregnancies were viable. After adjustments for confounders, the positive association remained. 相似文献997.
Su Yeoun Kim Young Joo Jeon Seung Hun Oh Hyun Sook Kim Ok Joon Kim Doyeun Oh Mingull Jeung Byung Soo Shin Young Seok Park Nam Keun Kim 《Genes & genomics.》2012,34(5):485-492
Kinase insert domain receptor (KDR) gene polymorphisms are associated with coronary artery lesions. The aims of this study were to evaluate the role of KDR polymorphisms in patients susceptible to cerebral white matter lesion (cWML), and determine the relationship between KDR polymorphisms and plasma total homocysteine levels. A total of 326 study subjects who had never had a stroke were enrolled in this study. The indices of cWMLs included total WML (TWML), periventricular white matter lesion (PWML), and subcortical white matter lesion (SCWML) in brain fluid-attenuated inversion recovery images. Among the 326 study subjects, TWML was found in 65 patients (20%). Common genetic variants of KDR (?604, 1192, and 1719) were examined. In multivariate analysis, there were no significant effects of any tested KDR polymorphisms on cWML. A significant association with plasma total homocysteine levels was found for TWML. The haplotypes of the KDR -604, 1192, and 1719 polymorphisms were associated with the increased risk of development of cWML. We conclude that the haplotypes of KDR polymorphisms are associated with an increased risk of development of cWML. 相似文献
998.
La WG Bhang SH Shin JY Yoon HH Park J Yang HS Yu SH Sung YE Kim BS 《Biotechnology progress》2012,28(4):1055-1060
In this article, we examined the feasibility of using 3,4‐dihydroxy‐L ‐phenylalanine (DOPA) as a cell adhesion molecule in serum‐free cultures of anchorage‐dependent mammalian cells. DOPA is a critical, functional element in mussel adhesive proteins and is known to bind strongly to various natural or synthetic materials. DOPA coating on culture plates was confirmed using X‐ray photoelectron spectroscopy and energy‐dispersive spectroscopy. Human dermal fibroblasts (HDFs) were cultured on DOPA‐coated, fibronectin‐coated, or no material‐coated culture plates in serum‐free medium. HDFs cultured on DOPA showed the highest cell adhesion ratio, spreading, and viability but the lowest apoptotic activity. Therefore, DOPA may be a useful cell‐adhesion molecule for serum‐free culture. © 2012 American Institute of Chemical Engineers Biotechnol. Prog., 28: 1055–1060, 2012 相似文献
999.
1000.