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Find video protocols related to scientific articles indexed in Pubmed.
Pressure adaptation is linked to thermal adaptation in salt-saturated marine habitats.
Environ. Microbiol.
PUBLISHED: 10-02-2014
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The present study provides a deeper view of protein functionality as a function of temperature, salt and pressure in deep-sea habitats. A set of 8 different enzymes from five distinct deep-sea (3,040-4,908 m depth), moderately warm (14.0-16.5°C) biotopes, characterised by a wide range of salinities (39-348 practical salinity units), were investigated for this purpose. An enzyme from a 'superficial' marine hydrothermal habitat (65°C) was isolated and characterised for comparative purposes. We report here the first experimental evidence suggesting that in salt-saturated deep-sea habitats, the adaptation to high pressure is linked to high thermal resistance (p value = 0.0036). Salinity might, therefore, increase the temperature window for enzyme activity, and possibly microbial growth, in deep-sea habitats. As an example, Lake Medee, the largest hypersaline deep-sea anoxic lake of the Eastern Mediterranean Sea, where the water temperature is never higher than 16°C, was shown to contain halopiezophilic-like enzymes that are most active at 70°C and with denaturing temperatures of 71.4°C. The determination of the crystal structures of 5 proteins revealed unknown molecular mechanisms involved in protein adaptation to poly-extremes as well as distinct active site architectures and substrate preferences relative to other structurally characterised enzymes.
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Reduce readmissions with service-based care management.
Prof Case Manag
PUBLISHED: 10-02-2014
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In response to the U.S. Affordable Care Act, the Centers for Medicare & Medicaid Services proposed a change in reimbursement penalties for hospitals beginning October 1, 2012. Reducing the occurrence of unplanned readmissions has become a more urgently focused topic. As part of the health care system, care management aligns with physicians to significantly improve service, financial, and clinical care outcomes. To address the changing health care climate in 2008, care management services were restructured at an academic university medical center located in 1 of the 3 largest counties in California. Changing from a unit-based to a service-based care management model partnered care managers and social workers with physician services. We sought to assess the effect of this change on surrogates for patient experience and clinical quality of care.
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THOC5 controls 3'end-processing of immediate early genes via interaction with polyadenylation specific factor 100 (CPSF100).
Nucleic Acids Res.
PUBLISHED: 10-01-2014
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Transcription of immediate early genes (IEGs) in response to extrinsic and intrinsic signals is tightly regulated at multiple stages. It is known that untranslated regions of the RNA can play a role in these processes. Here we show that THOC5, a member of the TREX (transcription/export) complex, plays a role in expression of only a subset of constitutively active genes, however transcriptome analysis reveals that more than 90% of IEG were not induced by serum in THOC5 depleted cells. Furthermore, THOC5 depletion does not influence the expression of the most rapidly induced IEGs, e.g. Fos and Jun. One group of THOC5 target genes, including Id1, Id3 and Wnt11 transcripts, were not released from chromatin in THOC5 depleted cells. Genes in another group, including Myc and Smad7 transcripts, were released with shortening of 3'UTR by alternative cleavage, and were spliced but export was impaired in THOC5 depleted cells. By interactome analysis using THOC5 as bait, we show that upon stimulation with serum THOC5 forms a complex with polyadenylation-specific factor 100 (CPSF100). THOC5 is required for recruitment of CPSF100 to 3'UTR of THOC5 target genes. These data suggest the presence of a novel mechanism for the control of IEG response by THOC5 via 3'end-processing.
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Hypotensive effects and angiotensin-converting enzyme inhibitory peptides of reishi (Ganoderma lingzhi) auto-digested extract.
Molecules
PUBLISHED: 08-29-2014
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Reishi (Ganoderma lingzhi) has been used as a traditional medicine for millennia. However, relatively little is known about this mushroom's proteins and their bioactivities. In this study, we used reishi's own proteases to hydrolyze its protein and obtained auto-digested reishi (ADR) extract. The extract was subjected to in vitro assays and administered to spontaneous hypertensive rats (SHRs) to determine its potential for use as a hypotensive medication. Bioassay-guided fractionation and de novo sequencing were used for identifying the active compounds. After 4 h administration of ADR, the systolic pressure of SHRs significantly decreased to 34.3 mmHg (19.5% change) and the effect was maintained up to 8 h of administration, with the decrease reaching as low as 26.8 mmHg (15% reduction-compare to base line a decrease of 26.8 mmHg is less than a decrease of 34.3 mmHg so it should give a smaller % reduction). Eleven peptides were identified and four of them showed potent inhibition against ACE with IC50 values ranging from 73.1 ?M to 162.7 ?M. The results showed that ADR could be a good source of hypotensive peptides that could be used for antihypertensive medication or incorporation into functional foods.
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A Phase I/II Study Combining Erlotinib and Dasatinib for Non-Small Cell Lung Cancer.
Oncologist
PUBLISHED: 08-28-2014
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EGFR and Src are frequently activated in non-small cell lung cancer (NSCLC). In preclinical models, combining EGFR and Src inhibition has additive synergistic effects. We conducted a phase I/II trial of the combination of Src inhibitor dasatinib with EGFR inhibitor erlotinib to determine the maximum tolerated dose (MTD), pharmacokinetic drug interactions, biomarkers, and efficacy in NSCLC.
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Potent angiotensin-converting enzyme inhibitory tripeptides identified by a computer-based approach.
J. Mol. Graph. Model.
PUBLISHED: 08-23-2014
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Currently, peptides and peptidomimetics are the main focus in attempts to identify inhibitors of angiotensin-converting enzyme (ACE), the dipeptidyl carboxypeptidase that causes blood vessels to constrict and blood pressure to increase. This study was conducted to identify the most potent ACE-inhibitory tripeptides with a proline C-terminus, using a novel three-step (tautomerization-docking-ADME simulation) virtual screening process and in vitro assays. Sixteen candidates were identified, and their IC50 values ranged from 5.6 to 274.4?M. ACE inhibition activity for 14 of the 16 tripeptides was reported for the first time. We also found that changing from the L-form to the D-form of the amino acid at the amino and carboxyl termini resulted in a decrease of inhibition, but a greater decrease was observed for C-terminal changes. With low IC50 values and high-predicted bioavailability, the peptides identified by our protocol are comparable in terms of ACE-inhibition to those derived from costly and time-consuming wet screening. Our in vitro and docking results showed that the configuration of the C-terminus is a critical parameter contributing to the inhibitory activity of tripeptides with proline at this position. These findings will contribute to the use of simulation tools for rational drug design, especially for ACE inhibitors.
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The environment shapes microbial enzymes: five cold-active and salt-resistant carboxylesterases from marine metagenomes.
Appl. Microbiol. Biotechnol.
PUBLISHED: 04-29-2014
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Most of the Earth's biosphere is cold and is populated by cold-adapted microorganisms. To explore the natural enzyme diversity of these environments and identify new carboxylesterases, we have screened three marine metagenome gene libraries for esterase activity. The screens identified 23 unique active clones, from which five highly active esterases were selected for biochemical characterization. The purified metagenomic esterases exhibited high activity against ?-naphthyl and p-nitrophenyl esters with different chain lengths. All five esterases retained high activity at 5 °C indicating that they are cold-adapted enzymes. The activity of MGS0010 increased more than two times in the presence of up to 3.5 M NaCl or KCl, whereas the other four metagenomic esterases were inhibited to various degrees by these salts. The purified enzymes showed different sensitivities to inhibition by solvents and detergents, and the activities of MGS0010, MGS0105 and MGS0109 were stimulated three to five times by the addition of glycerol. Screening of purified esterases against 89 monoester substrates revealed broad substrate profiles with a preference for different esters. The metagenomic esterases also hydrolyzed several polyester substrates including polylactic acid suggesting that they can be used for polyester depolymerization. Thus, esterases from marine metagenomes are cold-adapted enzymes exhibiting broad biochemical diversity reflecting the environmental conditions where they evolved.
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Hippocampal place cell responses to distal and proximal cue manipulations in dopamine D2 receptor-knockout mice.
Brain Res.
PUBLISHED: 03-25-2014
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The human hippocampus is critical for learning and memory. In rodents, hippocampal pyramidal neurons fire in a location-specific manner and form relational representations of environmental cues. The important roles of dopaminergic D1 receptors in learning and in hippocampal neural synaptic plasticity in novel environments have been previously shown. However, the roles of D2 receptors in hippocampal neural plasticity in response to novel and familiar spatial stimuli remain unclear. In order to clarify this issue, we recorded from hippocampal neurons in dopamine D2 receptor-knockout (D2R-KO) mice and their wild-type (WT) littermates during manipulations of distinct spatial cues in familiar and novel environments. Here, we report that D2R-KO mice showed substantial deficits in place-cell properties (number of place cells, intra-field firing rates, spatial tuning, and spatial coherence). Furthermore, although place cells in D2R-KO mice responded to manipulations of distal and proximal cues in both familiar and novel environments in a manner that was similar to place cells in WT mice, place fields were less stable in the D . The axes represent the differences between the peak and the valley of each waveform of EL2 and EL3.2R-KO mice in the familiar environment, but not in the novel environment. The present results suggested that D2 receptors in the hippocampus are important for place response stability. The place-cell properties of D2R-KO mice were similar to aged animals, suggesting that the alterations of place-cell properties in aged animals might be ascribed partly to alterations in the D2R in the HF of aged animals.
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Vandetanib and indwelling pleural catheter for non-small-cell lung cancer with recurrent malignant pleural effusion.
Clin Lung Cancer
PUBLISHED: 02-13-2014
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Non-small-cell lung cancer patients with malignant pleural effusion have a poor overall median survival (4.3 months). VEGF is a key regulator of pleural effusion production. It is unknown if pharmacological inhibition of VEGF signaling modifies the disease course of non-small-cell lung cancer patients with recurrent malignant pleural effusion. We report the final results of a single-arm phase II clinical trial of the VEGF receptor inhibitor, vandetanib, combined with intrapleural catheter placement in patients with non-small-cell lung cancer and recurrent malignant pleural effusion, to determine whether vandetanib reduces time to pleurodesis.
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Wild Mushrooms in Nepal: Some Potential Candidates as Antioxidant and ACE-Inhibition Sources.
Evid Based Complement Alternat Med
PUBLISHED: 01-28-2014
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Twenty-nine mushrooms collected in the mountainous areas of Nepal were analyzed for antioxidant activity by different methods, including Folin-Ciocalteu, ORAC, ABTS, and DPPH assays. Intracellular H2O2-scavenging activity was also performed on HaCaT cells. The results showed that phenolic compounds are the main antioxidant of the mushrooms. Among studied samples, Inonotus andersonii, and Phellinus gilvus exhibited very high antioxidant activity with the phenolic contents up to 310.8 and 258.7?mg GAE/g extracts, respectively. The H2O2-scavenging assay on cells also revealed the potential of these mushrooms in the prevention of oxidative stress. In term of ACE-inhibition, results showed that Phlebia tremellosa would be a novel and promising candidate for antihypertensive studies. This mushroom exhibited even higher in vitro ACE-inhibition activity than Ganoderma lingzhi, with the IC50 values of the two mushrooms being 32? ? g/mL and 2? ? g/mL, respectively. This is the first time biological activities of mushrooms collected in Nepal were reported. Information from this study should be a valuable reference for future studies on antioxidant and ACE-inhibitory activities of mushrooms.
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Geranyl dihydrochalcones from Artocarpus altilis and their antiausteric activity.
Planta Med.
PUBLISHED: 01-15-2014
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Human pancreatic cancer cell lines have remarkable tolerance to nutrition starvation, which enables them to survive under a tumor microenvironment. The search for agents that preferentially inhibit the survival of cancer cells under low nutrient conditions is a novel antiausterity strategy in anticancer drug discovery. In this study, the methanolic extract of the leaves of Artocarpus altilis showed 100?% preferential cytotoxicity against PANC-1 human pancreatic cancer cells under nutrient-deprived conditions at a concentration of 50?µg/mL. Further investigation of this extract led to the isolation of eight new geranylated dihydrochalcones named sakenins A-H (1-8) together with four known compounds (9-12). Among them, sakenins F (6) and H (8) were identified as potent preferentially cytotoxic candidates with PC50 values of 8.0?µM and 11.1?µM, respectively.
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Nonspecific cleavage of proteins using graphene oxide.
Anal. Biochem.
PUBLISHED: 01-08-2014
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In this article, we report the intrinsic catalytic activity of graphene oxide (GO) for the nonspecific cleavage of proteins. We used bovine serum albumin (BSA) and a recombinant esterase (rEstKp) from the cold-adapted bacterium Pseudomonas mandelii as test proteins. Cleavage of BSA and rEstKp was nonspecific regarding amino acid sequence, but it exhibited dependence on temperature, time, and the amount of GO. However, cleavage of the proteins did not result in complete hydrolysis into their constituent amino acids. GO also invoked hydrolysis of p-nitrophenyl esters at moderate temperatures lower than those required for peptide hydrolysis regardless of chain length of the fatty acyl esters. Based on the results, the functional groups of GO, including alcohols, phenols, and carboxylates, can be considered as crucial roles in the GO-mediated hydrolysis of peptides and esters via general acid-base catalysis. Our findings provide novel insights into the role of GO as a carbocatalyst with nonspecific endopeptidase activity in biochemical reactions.
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Halorhabdus tiamatea: proteogenomics and glycosidase activity measurements identify the first cultivated euryarchaeon from a deep-sea anoxic brine lake as potential polysaccharide degrader.
Environ. Microbiol.
PUBLISHED: 01-05-2014
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Euryarchaea from the genus Halorhabdus have been found in hypersaline habitats worldwide, yet are represented by only two isolates: Halorhabdus utahensis?AX-2(T) from the shallow Great Salt Lake of Utah, and Halorhabdus tiamatea?SARL4B(T) from the Shaban deep-sea hypersaline anoxic lake (DHAL) in the Red Sea. We sequenced the H.?tiamatea genome to elucidate its niche adaptations. Among sequenced archaea, H.?tiamatea features the highest number of glycoside hydrolases, the majority of which were expressed in proteome experiments. Annotations and glycosidase activity measurements suggested an adaptation towards recalcitrant algal and plant-derived hemicelluloses. Glycosidase activities were higher at 2% than at 0% or 5% oxygen, supporting a preference for low-oxygen conditions. Likewise, proteomics indicated quinone-mediated electron transport at 2% oxygen, but a notable stress response at 5% oxygen. Halorhabdus tiamatea furthermore encodes proteins characteristic for thermophiles and light-dependent enzymes (e.g. bacteriorhodopsin), suggesting that H.?tiamatea evolution was mostly not governed by a cold, dark, anoxic deep-sea habitat. Using enrichment and metagenomics, we could demonstrate presence of similar glycoside hydrolase-rich Halorhabdus members in the Mediterranean DHAL Medee, which supports that Halorhabdus species can occupy a distinct niche as polysaccharide degraders in hypersaline environments.
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Synthesis of halogenated 4-quinolones and evaluation of their antiplasmodial activity.
Bioorg. Med. Chem. Lett.
PUBLISHED: 01-04-2014
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Treatment of 4-hydroxyquinolines with (2-methyl)allyl bromide in the presence of K2CO3 resulted in the formation of novel N-[(2-methyl)allyl]-4-quinolones through selective N-alkylation. Further reaction of N-(2-methylallyl)-4-quinolones with bromine or N-bromosuccinimide yielded the corresponding 3-bromo-1-(2,3-dibromo-2-methylpropyl)-4-quinolones and 3-bromo-1-(2-methylallyl)-4-quinolones, respectively. Furthermore, a copper-catalyzed C-N coupling of the latter 3-bromo-4-quinolones with (5-chloro)indole afforded novel 3-[(5-chloro)indol-1-yl]-4-quinolone hybrids. Antifungal and antiplasmodial assays of all new 4-quinolones were performed and revealed no antifungal properties but moderate antiplasmodial activities. All 15 compounds displayed micromolar activities against a chloroquine-sensitive strain of Plasmodium falciparum, and the five most potent compounds also showed micromolar activities against a chloroquine-resistant strain of P. falciparum with IC50-values ranging between 4 and 70 ?M.
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Zinc and Zinc Transporters in Macrophages and Their Roles in Efferocytosis in COPD.
PLoS ONE
PUBLISHED: 01-01-2014
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Our previous studies have shown that nutritional zinc restriction exacerbates airway inflammation accompanied by an increase in caspase-3 activation and an accumulation of apoptotic epithelial cells in the bronchioles of the mice. Normally, apoptotic cells are rapidly cleared by macrophage efferocytosis, limiting any secondary necrosis and inflammation. We therefore hypothesized that zinc deficiency is not only pro-apoptotic but also impairs macrophage efferocytosis. Impaired efferocytic clearance of apoptotic epithelial cells by alveolar macrophages occurs in chronic obstructive pulmonary disease (COPD), cigarette-smoking and other lung inflammatory diseases. We now show that zinc is a factor in impaired macrophage efferocytosis in COPD. Concentrations of zinc were significantly reduced in the supernatant of bronchoalveolar lavage fluid of patients with COPD who were current smokers, compared to healthy controls, smokers or COPD patients not actively smoking. Lavage zinc was positively correlated with AM efferocytosis and there was decreased efferocytosis in macrophages depleted of Zn in vitro by treatment with the membrane-permeable zinc chelator TPEN. Organ and cell Zn homeostasis are mediated by two families of membrane ZIP and ZnT proteins. Macrophages of mice null for ZIP1 had significantly lower intracellular zinc and efferocytosis capability, suggesting ZIP1 may play an important role. We investigated further using the human THP-1 derived macrophage cell line, with and without zinc chelation by TPEN to mimic zinc deficiency. There was no change in ZIP1 mRNA levels by TPEN but a significant 3-fold increase in expression of another influx transporter ZIP2, consistent with a role for ZIP2 in maintaining macrophage Zn levels. Both ZIP1 and ZIP2 proteins were localized to the plasma membrane and cytoplasm in normal human lung alveolar macrophages. We propose that zinc homeostasis in macrophages involves the coordinated action of ZIP1 and ZIP2 transporters responding differently to zinc deficiency signals and that these play important roles in macrophage efferocytosis.
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Oxidative stress decreases functional airway mannose binding lectin in COPD.
PLoS ONE
PUBLISHED: 01-01-2014
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We have previously established that a defect in the ability of alveolar macrophages (AM) to phagocytose apoptotic cells (efferocytosis) and pathogens is a potential therapeutic target in COPD. We further showed that levels of mannose binding lectin (MBL; required for effective macrophage phagocytic function) were reduced in the airways but not circulation of COPD patients. We hypothesized that increased oxidative stress in the airway could be a cause for such disturbances. We therefore studied the effects of oxidation on the structure of the MBL molecule and its functional interactions with macrophages. Oligomeric structure of plasma derived MBL (pdMBL) before and after oxidation (oxMBL) with 2,2'-azobis(2-methylpropionamidine)dihydrochroride (AAPH) was investigated by blue native PAGE. Macrophage function in the presence of pd/oxMBL was assessed by measuring efferocytosis, phagocytosis of non-typeable Haemophilus influenzae (NTHi) and expression of macrophage scavenger receptors. Oxidation disrupted higher order MBL oligomers. This was associated with changed macrophage function evident by a significantly reduced capacity to phagocytose apoptotic cells and NTHi in the presence of oxMBL vs pdMBL (eg, NTHi by 55.9 and 27.0% respectively). Interestingly, oxidation of MBL significantly reduced macrophage phagocytic ability to below control levels. Flow cytometry and immunofluorescence revealed a significant increase in expression of macrophage scavenger receptor (SRA1) in the presence of pdMBL that was abrogated in the presence of oxMBL. We show the pulmonary macrophage dysfunction in COPD may at least partially result from an oxidative stress-induced effect on MBL, and identify a further potential therapeutic strategy for this debilitating disease.
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Pulvinar neurons reveal neurobiological evidence of past selection for rapid detection of snakes.
Proc. Natl. Acad. Sci. U.S.A.
PUBLISHED: 10-28-2013
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Snakes and their relationships with humans and other primates have attracted broad attention from multiple fields of study, but not, surprisingly, from neuroscience, despite the involvement of the visual system and strong behavioral and physiological evidence that humans and other primates can detect snakes faster than innocuous objects. Here, we report the existence of neurons in the primate medial and dorsolateral pulvinar that respond selectively to visual images of snakes. Compared with three other categories of stimuli (monkey faces, monkey hands, and geometrical shapes), snakes elicited the strongest, fastest responses, and the responses were not reduced by low spatial filtering. These findings integrate neuroscience with evolutionary biology, anthropology, psychology, herpetology, and primatology by identifying a neurobiological basis for primates heightened visual sensitivity to snakes, and adding a crucial component to the growing evolutionary perspective that snakes have long shaped our primate lineage.
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Comprehensive Biomarker Analysis and Final Efficacy Results of Sorafenib in the BATTLE Trial.
Clin. Cancer Res.
PUBLISHED: 10-28-2013
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To report the clinical efficacy of sorafenib and to evaluate biomarkers associated with sorafenib clinical benefit in the BATTLE (Biomarker-Integrated Approaches of Targeted Therapy for Lung Cancer Elimination) program. Patients and Methods: Patients with previously treated non-small cell lung cancer (NSCLC) received sorafenib until progression or unacceptable toxicity. Eight-week disease control rate (DCR), progression-free survival (PFS), and overall survival (OS) were assessed. Prespecified biomarkers included K-RAS, EGFR, and B-RAF mutations, and EGFR gene copy number. Gene expression profiles from NSCLC cell lines and patient tumor biopsies with wild-type EGFR were used to develop a sorafenib sensitivity signature (SSS).
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Rational design and synthesis of topoisomerase I and II inhibitors based on oleanolic acid moiety for new anti-cancer drugs.
Bioorg. Med. Chem.
PUBLISHED: 10-08-2013
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Semisynthetic reactions were conducted on oleanolic acid, a common plant-derived oleanane-type triterpene. Ten rationally designed derivatives of oleanolic acid were synthesized based on docking studies and tested for their topoisomerase I and II? inhibitory activity. Semisynthetic reactions targeted C-3, C-12, C-13, and C-17. Nine of the synthesized compounds were identified as new compounds. The structures of these compounds were confirmed by spectroscopic methods (1D, 2D NMR and MS). Five oleanolic acid analogues (S2, S3, S5, S7 and S9) showed higher activity than camptothecin (CPT) in the topoisomerase I DNA relaxation assay. Four oleanolic acid analogues (S2, S3, S5 and S6) showed higher activity than etoposide in a topoisomerase II assay. The results indicated that the C12-C13 double bond of the oleanolic acid skeleton is important for the inhibitory activity against both types of topoisomerases, while insertion of a longer chain at either position 3 or 17 increases the activity against topoisomerases by various degrees. Some of the synthesized compounds act as dual inhibitors for both topoisomerase I and II?.
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Redox-responsive self-healing for corrosion protection.
Adv. Mater. Weinheim
PUBLISHED: 07-01-2013
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Raspberry-shaped redox-responsive capsules for storing corrosion inhibitors are introduced, targeted to solve the drawbacks of conducting-polymer-based coating systems for corrosion protection. These capsules synthesized via the miniemulsion technique have a remarkable release property upon reduction (onset of corrosion) and cease release upon reoxidation (passivation of the defect). The self-healing capability is demonstrated by application of these capsules as part of a composite coating on zinc.
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Genome sequence and functional genomic analysis of the oil-degrading bacterium Oleispira antarctica.
Nat Commun
PUBLISHED: 06-18-2013
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Ubiquitous bacteria from the genus Oleispira drive oil degradation in the largest environment on Earth, the cold and deep sea. Here we report the genome sequence of Oleispira antarctica and show that compared with Alcanivorax borkumensis--the paradigm of mesophilic hydrocarbonoclastic bacteria--O. antarctica has a larger genome that has witnessed massive gene-transfer events. We identify an array of alkane monooxygenases, osmoprotectants, siderophores and micronutrient-scavenging pathways. We also show that at low temperatures, the main protein-folding machine Cpn60 functions as a single heptameric barrel that uses larger proteins as substrates compared with the classical double-barrel structure observed at higher temperatures. With 11 protein crystal structures, we further report the largest set of structures from one psychrotolerant organism. The most common structural feature is an increased content of surface-exposed negatively charged residues compared to their mesophilic counterparts. Our findings are relevant in the context of microbial cold-adaptation mechanisms and the development of strategies for oil-spill mitigation in cold environments.
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Physical and chemical stability of reconstituted and diluted dexrazoxane infusion solutions.
J Oncol Pharm Pract
PUBLISHED: 05-14-2013
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Background and purposeDexrazoxane is used clinically to prevent anthracycline-associated cardiotoxicity. Hydrolysis of dexrazoxane prior to reaching the cardiac membranes severely hampers its mode of action; therefore, degradation during the preparation and administration of intravenous dexrazoxane admixtures demands special attention. Moreover, the ongoing national shortage of one dexrazoxane formulation in the United States has forced pharmacies to dispense other commercially available dexrazoxane products. However, the manufacturers limited stability data restrict the flexibility of dexrazoxane usage in clinical practice. The aims of this study are to determine the physical and chemical stability of reconstituted and diluted solutions of two commercially available dexrazoxane formulations. METHODS: /st>The stability of two dexrazoxane products, brand and generic name, in reconstituted and intravenous solutions stored at room temperature without light protection in polyvinyl chloride bags was determined. The concentrations of dexrazoxane were measured at predetermined time points up to 24?h using a validated reversed phase high-performance liquid chromatography with ultraviolet detection assay. RESULTS: /st>Brand (B-) and generic (G-) dexrazoxane products, reconstituted in either sterile water or 0.167?M sodium lactate (final concentration of 10?mg/mL), were found stable for at least to 8 h. Infusion solutions of B-dexrazoxane, prepared according to each manufacturers directions, were stable for at least 24 h and 8?h at 1?mg/mL and 3?mg/mL, respectively. Infusion solutions of G-dexrazoxane, prepared in either 5% dextrose or 0.9% sodium chloride following the manufacturers guidelines, were also stable for at least 24 h and 8?h at 1?mg/mL and 3?mg/mL, respectively. All tested solutions were found physically stable up to 24 h at room temperature. CONCLUSION: /st>The stability of dexrazoxane infusion solutions reported herein permits advance preparation of dexrazoxane intravenous admixtures, facilitating pharmacy workflow and clinical operations. However, due to the potential risks of fluid overload when these intravenous solutions are administered to patients, caution is advised to ensure patient safety.
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Evaluation of (4-aminobutyloxy)quinolines as a novel class of antifungal agents.
Bioorg. Med. Chem. Lett.
PUBLISHED: 05-09-2013
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Antifungal assessment of eighteen 5-, 6- and 8-(4-aminobutyloxy)quinolines revealed a significant susceptibility of the tested fungi and yeast strains (Candida albicans, Rhodotorula bogoriensis, Aspergillus flavus and Fusarium solani) toward different halo-substituted 8-(4-aminobutyloxy)quinolines. The six most potent compounds displayed antifungal activities similar to those of established antifungal agents such as Amphotericin B, Fluconazole and Itraconazole, and one representative also showed a promising broad-spectrum antifungal profile. The introduction of an aminoalkoxy side chain at the 8-position of a halo-substituted quinoline core might thus provide a new class of lead structures in the search for novel antifungal agents.
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Genome Sequence of Thalassolituus oleivorans MIL-1 (DSM 14913T).
Genome Announc
PUBLISHED: 04-20-2013
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Thalassolituus oleivorans is one of the most prevalent marine gammaproteobacteria in microbial communities, emerging after oil spills in coastal, estuarine, and surface seawaters. Here, we present the assembled genome of strain T. oleivorans MIL-1 (DSM 14913(T)), which is 3,920,328 bp with a G+C content of 46.6%.
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Clinical and biomarker outcomes of the phase II vandetanib study from the BATTLE trial.
J Thorac Oncol
PUBLISHED: 04-16-2013
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The Biomarker-integrated Approaches of Targeted Therapy for Lung Cancer Elimination trial prospectively obtained serum and tumor core biopsies and randomized 255 chemorefractory non-small-cell lung cancer (NSCLC) patients into four phase II trials: erlotinib, erlotinib-bexarotene, vandetanib, or sorafenib. Herein, we report the clinical and biomarker results of the phase II vandetanib trial.
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Maternal risk factors associated with increased dioxin concentrations in breast milk in a hot spot of dioxin contamination in Vietnam.
J Expo Sci Environ Epidemiol
PUBLISHED: 04-15-2013
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This study looked to identify determinants of exposure to dioxin in breast milk from breast-feeding women in a hot spot of dioxin exposure in Vietnam. Breast milk was collected from 140 mothers 1 month after delivery. The risk factors investigated included length of residency, drinking of well water and the frequency of animal food consumption. Cluster analysis was performed to identify dietary patterns of fish and meat portions, fish variety and egg variety. Residency, age and parity were clearly associated with increased dioxin levels. Drinking well water and the consumption of marine crab and shrimps were related to higher levels of furans in breast milk. The consumption of quail eggs also appeared to be associated with increased levels of some dioxin isomers in this area. Some mothers who ate no or less meat than fish and mothers who consumed more freshwater fish than marine fish had lower levels of dioxins in their breast milk. However, the type of water and the eating habits of mothers contributed only partly to the increased dioxin levels in their breast milk; the length of residency was the most important risk factor associated with increased dioxin body burdens of mothers.Journal of Exposure Science and Environmental Epidemiology advance online publication, 23 October 2013; doi:10.1038/jes.2013.73.
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Dioxin exposure in breast milk and infant neurodevelopment in Vietnam.
Occup Environ Med
PUBLISHED: 02-06-2013
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Dioxin levels in the breast milk of mothers residing near hot spots of dioxin contamination areas in South Vietnam remain much higher than in unsprayed areas, suggesting that fetuses and breast-fed infants may be exposed to high levels of dioxins. The present study investigated the association of infant neurodevelopment in early infancy and dioxin exposure during the perinatal period.
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Place-related neuronal activity in the monkey parahippocampal gyrus and hippocampal formation during virtual navigation.
Hippocampus
PUBLISHED: 01-10-2013
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Neuropsychological data in primates demonstrated a pivotal role of the hippocampal formation (HF) and parahippocampal gyrus (PH) in navigation and episodic memory. To investigate the role of HF and PH neurons in environmental scaling in primates, we recorded neuronal activities in the monkey HF and PH during virtual navigation (VN) and pointer translocation (PT) tasks. The monkeys had to navigate within three differently sized virtual spaces with the same spatial cues (VN task) or move a pointer on a screen (PT task) by manipulating a joystick to receive a reward. Of the 234 recorded neurons, 170 and 61 neurons displayed place-related activities in the VN and PT tasks, respectively. Significant differences were observed between the HF and PH neurons. The spatial similarity of place fields between the two different virtual spaces was lower in PH than in HF, while specificities of the neuronal responses to distal spatial cues were higher in PH than in HF. Spatial view information was predominately processed in posterior PH. The spatial scales (place field sizes) of the HF and PH neurons were reduced in the reduced virtual space, as shown in rodent place cells. These results suggest the complementary roles of HF (allocentric representation of landmarks) and PH (representation of the spatial layout of landmarks) in the recognition of a location during navigation. © 2013 Wiley Periodicals, Inc.
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The association of alternate VEGF ligands with resistance to anti-VEGF therapy in metastatic colorectal cancer.
PLoS ONE
PUBLISHED: 01-01-2013
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Circulating angiogenic factors are altered in patients with mCRC receiving bevacizumab. Evaluation of alterations in levels of VEGF ligands may provide insights into possible resistance mechanisms.
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Evolution of iridium-based molecular catalysts during water oxidation with ceric ammonium nitrate.
J. Am. Chem. Soc.
PUBLISHED: 11-07-2011
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Organometallic iridium complexes have been reported as water oxidation catalysts (WOCs) in the presence of ceric ammonium nitrate (CAN). One challenge for all WOCs regardless of the metal used is stability. Here we provide evidence for extensive modification of many Ir-based WOCs even after exposure to only 5 or 15 equiv of Ce(IV) (whereas typically 100-10000 equiv are employed during WOC testing). We also show formation of Ir-rich nanoparticles (likely IrO(x)) even in the first 20 min of reaction, associated with a Ce matrix. A combination of UV-vis and NMR spectroscopy, scanning transmission electron microscopy, and powder X-ray diffraction is used. Even simple IrCl(3) is an excellent catalyst. Our results point to the pitfalls of studying Ir WOCs using CAN.
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Beyond VEGF: inhibition of the fibroblast growth factor pathway and antiangiogenesis.
Clin. Cancer Res.
PUBLISHED: 09-27-2011
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Fibroblast growth factor (FGF) signaling regulates cell proliferation, differentiation, survival, angiogenesis, and wound healing. Compelling evidence for deregulated FGF signaling in tumorigenesis continues to emerge, and a growing body of research suggests that FGF may also play an integral role in the resistance to anti-VEGF therapy. Although agents targeting FGF signaling are early in development, the potential to target both the VEGF and FGF pathways may translate into improvements in the clinical care of cancer patients.
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An ataxia-telangiectasia-mutated (ATM) kinase mediated response to DNA damage down-regulates the mRNA-binding potential of THOC5.
RNA
PUBLISHED: 09-21-2011
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In response to DNA damage, transcription is blocked by inhibition of RNA polymerase II activity. The regulation of a preexisting pool of mRNAs, therefore, plays a key role in DNA repair, cell cycle arrest, or inhibition of differentiation. THOC5 is a member of the THO complex and plays a role in the export of a subset of mRNA, which plays an important role in hematopoiesis and maintaining primitive cells. Since three serine residues in the PEST domain of THOC5 have been shown to be directly phosphorylated by ataxia-telangiectasia-mutated (ATM) kinase, we examined the THOC5-dependent mRNA export under DNA damage. We show here that DNA damage drastically decreased the cytoplasmic pool of a set of THOC5-dependent mRNAs and impaired the THOC5/mRNA complex formation. The mRNP complex formed with nonphosphorylation mutant (S307/312/314A) THOC5, but not with a C-terminal deletion mutant after DNA damage, suggesting that the C-terminal domain of THOC5, but not its phosphorylation in the PEST domain, is necessary for the regulation of the mRNA-binding potency of THOC5. The cytoplasmic THOC5-dependent mRNAs were recovered by treatment with ATM kinase-specific or p53-specific siRNA, as well as by treatment with ATM kinase inhibitor, KU55933, under DNA damage conditions, suggesting that the ATM-kinase-p53 pathway is involved in this response to the DNA damage. Furthermore, the treatment with KU55933 blocked DNA damage-induced THOC5mRNP complex dissociation, indicating that activation of ATM kinase suppresses the ability of THOC5 to bind to its target mRNAs.
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Phase II trials of imatinib mesylate and docetaxel in patients with metastatic non-small cell lung cancer and head and neck squamous cell carcinoma.
J Thorac Oncol
PUBLISHED: 09-06-2011
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Two phase II clinical trials in the aerodigestive tumors were undertaken to evaluate the efficacy of imatinib mesylate-docetaxel. We hypothesized that imatinib mesylate would inhibit platelet-derived growth factor receptor (PDGFR) on pericytes and increase docetaxel uptake into tumor cells for an additive antitumor effect. Baseline tumor specimens, serum, and perfusion computed tomography (CT) scans were obtained for supportive evaluation.
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Biocatalytic production of novel glycolipids with cellodextrin phosphorylase.
Bioresour. Technol.
PUBLISHED: 08-05-2011
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Glycolipids have gained increasing attention as natural surfactants with a beneficial environmental profile. They are typically produced by fermentation, which only gives access to a limited number of structures. Here we describe the biocatalytic production of novel glycolipids with the cellodextrin phosphorylase from Clostridium stercorarium. This enzyme was found to display a broad donor and acceptor specificity, allowing the synthesis of five different products. Indeed, using either ?-glucose 1-phosphate or ?-galactose 1-phosphate as glycosyl donor, sophorolipid as well as glucolipid could be efficiently glycosylated. The transfer of a glucosyl moiety afforded a mixture of products that precipitated from the solution, resulting in near quantitative yields. The transfer of a galactosyl moiety, in contrast, generated a single product that remained in solution at thermodynamic equilibrium. These glycolipids not only serve as a new class of biosurfactants, but could also have applications in the pharmaceutical and nanomaterials industries.
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The combined mode of action of fipronil and amitraz on the motility of Rhipicephalus sanguineus.
Vet. Parasitol.
PUBLISHED: 07-23-2011
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The motility of adult Rhipicephalus sanguineus was evaluated subsequent to treatments of amitraz, fipronil and the combination of fipronil plus amitraz against a vehicle control in a Petri dish assay using the LemnaTec Scanalyzer Imaging System. The assay was run using a fixed dilution of amitraz (0.32?g/cm(2)); serial dilutions of fipronil (1.3, 0.33, 0.08, 0.02, or 0.005?g/cm(2)); and the same serial dilutions of fipronil in combination with the fixed dilution of amitraz. Measurement of motility was made of unstimulated ticks and then after stimulation at 1, 4, 18-22, and 24h post exposure (hpe) of the Petri dishes. For the unstimulated ticks, there was no difference in motility between the amitraz treatment group and the fipronil plus amitraz treatment group at the early time points. However, these two treatment groups had significantly higher motility than the solvent control and fipronil treatment groups. The unstimulated ticks in the amitraz treatment group had significantly higher motility than the fipronil plus amitraz treatment group at the later time points. Measurements after stimulation demonstrated there was no difference in motility between the amitraz treatment group and the fipronil plus amitraz treatment group at the early time points. By 18 hpe, the fipronil plus amitraz treatment group had significantly lower motility than all other treatment groups and at 21-22 and 24 hpe the other treatment groups did not differ from the control group. The action could be divided in two phases in the combination experiment: phase 1: an early increase in motility due to amitraz is identified in both amitraz alone or fipronil plus amitraz groups; phase 2: the combination of fipronil plus amitraz caused a significantly greater reduction in motility, suggesting mortality of the ticks, compared to fipronil or amitraz alone. These results demonstrate a synergism resulting from the combination of fipronil plus amitraz.
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Effect of low-fat diets on plasma levels of NF-?B-regulated inflammatory cytokines and angiogenic factors in men with prostate cancer.
Cancer Prev Res (Phila)
PUBLISHED: 07-15-2011
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Diet, nutritional status, and certain dietary supplements are postulated to influence the development and progression of prostate cancer. Angiogenesis and inflammation are central to tumor growth and progression, but the effect of diet on these processes remains uncertain. We explored changes in 50 plasma cytokines and angiogenic factors (CAF) in 145 men with prostate cancer enrolled in a preoperative, randomized controlled phase II trial with four arms: control (usual diet), low-fat (LF) diet, flaxseed-supplemented (FS) diet, and FS+LS diet. The mean duration of dietary intervention was 30 to 31 days. Among the individual arms, the largest number of significant changes (baseline vs. preoperative follow-up) was observed in the LF arm, with 19 CAFs decreasing and one increasing (P < 0.05). Compared with the control arm, 6 CAFs-including proangiogenic factors (stromal-cell derived-1?) and myeloid factors (granulocyte-colony-stimulating factor, macrophage colony-stimulating factor)-all decreased in the LF arm compared with controls; three and four CAFs changed in the FS and FS+LF arms, respectively. Weight loss occurred in the LF arms and significantly correlated with VEGF decreases (P < 0.001). The CAFs that changed in the LF arm are all known to be regulated by NF-?B, and a pathway analysis identified NF-?B as the most likely regulatory network associated with these changes in the LF arm but not in the FS-containing arms. These results suggest that a LF diet without flaxseed may reduce levels of specific inflammatory CAFs and suggests that the NF-?B pathway may be a mediator of these changes.
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Dioxin concentrations in breast milk of Vietnamese nursing mothers: a survey four decades after the herbicide spraying.
Environ. Sci. Technol.
PUBLISHED: 07-14-2011
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In an operation by United States Armed Forces during 1961 to 1971, large quantities of herbicides were sprayed in South Vietnam. These herbicides contained 2,3,7,8-tetrachlorodibenzo-p-dioxin (2,3,7,8-tetraCDD), the most toxic congener of dioxins. Several decades after the herbicide spraying ceased, dioxin concentrations in the environment and human remained elevated in the sprayed areas. Breast milk samples from 520 nursing mothers residing in areas including the hot spots as well as the sprayed and unsprayed areas were collected to quantify the levels of dioxins. The total toxic equivalents of 2,3,7,8-substitued PCDDs/PCDFs in breast milk of mothers living in the hot spots, and the sprayed and unsprayed areas were 14.10 pg/g lipid, 10.89 pg/g lipid, and 4.09 pg/g lipid for primiparae and 11.48 pg/g lipid, 7.56 pg/g lipid, and 2.84 pg/g lipid for multiparae, respectively, with significant differences in the values among the three areas. In the hot spots, dioxin levels were highly correlated with the residency of mothers after adjustment for their age and parity.
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The BATTLE trial: personalizing therapy for lung cancer.
Cancer Discov
PUBLISHED: 06-01-2011
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The Biomarker-integrated Approaches of Targeted Therapy for Lung Cancer Elimination (BATTLE) trial represents the first completed prospective, biopsy-mandated, biomarker-based, adaptively randomized study in 255 pretreated lung cancer patients. Following an initial equal randomization period, chemorefractory non-small cell lung cancer (NSCLC) patients were adaptively randomized to erlotinib, vandetanib, erlotinib plus bexarotene, or sorafenib, based on relevant molecular biomarkers analyzed in fresh core needle biopsy specimens. Overall results include a 46% 8-week disease control rate (primary end point), confirm prespecified hypotheses, and show an impressive benefit from sorafenib among mutant-KRAS patients. BATTLE establishes the feasibility of a new paradigm for a personalized approach to lung cancer clinical trials.
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Myeloid biomarkers associated with glioblastoma response to anti-VEGF therapy with aflibercept.
Clin. Cancer Res.
PUBLISHED: 06-01-2011
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VEGF and infiltrating myeloid cells are known regulators of tumor angiogenesis and vascular permeability in glioblastoma. We investigated potential blood-based markers associated with radiographic changes to aflibercept, which binds VEGF and placental growth factor (PlGF) in patients with recurrent glioblastoma.
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A phase 1 study of weekly everolimus (RAD001) in combination with docetaxel in patients with metastatic breast cancer.
Cancer
PUBLISHED: 05-02-2011
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Inhibition of mammalian target of rapamycin with everolimus may improve the efficacy of taxanes. Everolimus and docetaxel are both metabolized by CYP3A4, which could result in a pharmacokinetic (PK) interaction.
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Identification of mRNAs that are spliced but not exported to the cytoplasm in the absence of THOC5 in mouse embryo fibroblasts.
RNA
PUBLISHED: 04-27-2011
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The TREX (transcription/export) complex has been conserved throughout evolution from yeast to man and is required for coupled transcription elongation and nuclear export of mRNAs. The TREX complex in mammals and Drosophila is composed of the THO subcomplex (THOC1, THOC2, THOC5, THOC6, and THOC7), THOC3, UAP56, and Aly/THOC4. In human and Drosophila, various studies have shown that THO is required for the export of heat shock mRNAs, but nothing is known about other mRNAs. Our previous study using conditional THOC5 (or FMIP) knockout mice revealed that the presence of THOC5 is critical in hematopoietic cells but not for terminally differentiated cells. In this study, we describe the establishment of a mouse embryo fibroblast cell line (MEF), THOC5 flox/flox. Four days after infection of MEF THOC5 flox/flox with adenovirus carrying Cre-recombinase gene (Ad-GFP-Cre), THOC5 is down-regulated >95% at the protein level, and cell growth is strongly suppressed. Transcriptome analysis using cytoplasmic RNA isolated from cells lacking functional THOC5 reveals that only 2.9% of all genes were down-regulated more than twofold. Although we examined these genes in fibroblasts, one-fifth of all down-regulated genes (including HoxB3 and polycomb CBX2) are known to play a key role in hematopoietic development. We further identified 10 genes that are spliced but not exported to the cytoplasm in the absence of THOC5. These mRNAs were copurified with THOC5. Furthermore, Hsp70 mRNA was exported in the absence of THOC5 at 37°C, but not under heat shock condition (42°C), suggesting that THOC5 may be required for mRNA export under stress and/or upon signaling-induced conditions.
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Probing the active site of cellodextrin phosphorylase from Clostridium stercorarium: kinetic characterization, ligand docking, and site-directed mutagenesis.
Biotechnol. Prog.
PUBLISHED: 02-22-2011
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Cellodextrin phosphorylase from Clostridium stercorarium has been recombinantly expressed in Escherichia coli for the first time. Kinetic characterization of the purified enzyme has revealed that aryl and alkyl ?-glucosides can be efficiently glycosylated, an activity that has not yet been described for this enzyme class. To obtain a better understanding of the factors that determine the enzymes specificity, homology modeling and ligand docking were applied. Residue W168 has been found to form a hydrophobic stacking interaction with the substrate in subsite +2, and its importance has been examined by means of site-directed mutagenesis. The mutant W168A retains about half of its catalytic activity, indicating that other residues also contribute to the binding affinity of subsite +2. Finally, residue D474 has been identified as the catalytic acid, interacting with the glycosidic oxygen between subsites -1 and +1. Mutating this residue results in complete loss of activity. These results, for the first time, provide an insight in the enzyme-substrate interactions that determine the activity and specificity of cellodextrin phosphorylases.
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Immunological and viral determinants of dengue severity in hospitalized adults in Ha Noi, Viet Nam.
PLoS Negl Trop Dis
PUBLISHED: 01-19-2011
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The relationships between the infecting dengue serotype, primary and secondary infection, viremia and dengue severity remain unclear. This cross-sectional study examined these interactions in adult patients hospitalized with dengue in Ha Noi.
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An in-depth analysis of original antigenic sin in dengue virus infection.
J. Virol.
PUBLISHED: 10-27-2010
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The evolution of dengue viruses has resulted in four antigenically similar yet distinct serotypes. Infection with one serotype likely elicits lifelong immunity to that serotype, but generally not against the other three. Secondary or sequential infections are common, as multiple viral serotypes frequently cocirculate. Dengue infection, although frequently mild, can lead to dengue hemorrhagic fever (DHF) which can be life threatening. DHF is more common in secondary dengue infections, implying a role for the adaptive immune response in the disease. There is currently much effort toward the design and implementation of a dengue vaccine but these efforts are made more difficult by the challenge of inducing durable neutralizing immunity to all four viruses. Domain 3 of the dengue virus envelope protein (ED3) has been suggested as one such candidate because it contains neutralizing epitopes and it was originally thought that relatively few cross-reactive antibodies are directed to this domain. In this study, we performed a detailed analysis of the anti-ED3 response in a cohort of patients suffering either primary or secondary dengue infections. The results show dramatic evidence of original antigenic sin in secondary infections both in terms of binding and enhancement activity. This has important implications for dengue vaccine design because heterologous boosting is likely to maintain the immunological footprint of the first vaccination. On the basis of these findings, we propose a simple in vitro enzyme-linked immunosorbent assay (ELISA) to diagnose the original dengue infection in secondary dengue cases.
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Phase II study of dasatinib in patients with advanced non-small-cell lung cancer.
J. Clin. Oncol.
PUBLISHED: 09-20-2010
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Src family kinases (SFKs) promote cancer progression and are commonly expressed in non-small-cell lung cancer (NSCLC), but the clinical effects of SFK inhibition in NSCLC are unknown. We conducted a phase II trial of the SFK inhibitor dasatinib for advanced NSCLC. We tested the hypotheses that the activation of epidermal growth factor receptor (EGFR) or SFK or modulation of serum cytokines may predict a response to dasatinib.
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Effective drug delivery, in vitro and in vivo, by carbon-based nanovectors noncovalently loaded with unmodified Paclitaxel.
ACS Nano
PUBLISHED: 08-05-2010
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Many new drugs have low aqueous solubility and high therapeutic efficacy. Paclitaxel (PTX) is a classic example of this type of compound. Here we show that extremely small (<40 nm) hydrophilic carbon clusters (HCCs) that are PEGylated (PEG-HCCs) are effective drug delivery vehicles when simply mixed with paclitaxel. This formulation of PTX sequestered in PEG-HCCs (PTX/PEG-HCCs) is stable for at least 20 weeks. The PTX/PEG-HCCs formulation was as effective as PTX in a clinical formulation in reducing tumor volumes in an orthotopic murine model of oral squamous cell carcinoma. Preliminary toxicity and biodistribution studies suggest that the PEG-HCCs are not acutely toxic and, like many other nanomaterials, are primarily accumulated in the liver and spleen. This work demonstrates that carbon nanomaterials are effective drug delivery vehicles in vivo when noncovalently loaded with an unmodified drug.
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Phase 2 study of dasatinib in the treatment of head and neck squamous cell carcinoma.
Cancer
PUBLISHED: 07-22-2010
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Treatment options for patients with advanced head and neck squamous cell carcinoma (HNSCC) are scarce. This phase 2 study was conducted to evaluate the safety, tolerability, pharmacokinetics, and efficacy of dasatinib in this setting.
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Serum signature of hypoxia-regulated factors is associated with progression after induction therapy in head and neck squamous cell cancer.
Mol. Cancer Ther.
PUBLISHED: 06-08-2010
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Tumor hypoxia regulates many cytokines and angiogenic factors (CAF) and is associated with worse prognosis in head and neck squamous cell cancer (HNSCC). Serum CAF profiling may provide information regarding the biology of the host and tumor, prognosis, and response to therapy. We investigated 38 CAFs in HNSCC patients receiving induction therapy on a phase II trial of carboplatin, paclitaxel, and cetuximab. CAFs were measured by multiplex bead assay and enzyme-linked immunosorbent assay in 32 patients. Baseline and postinduction CAF levels were correlated with disease progression (PD) and human papilloma virus (HPV) status by Wilcoxon rank sum test. Baseline levels of eight hypoxia-regulated CAFs (the "high-risk signature" including vascular endothelial growth factor, interleukins 4 and 8, osteopontin, growth-related oncogene-alpha, eotaxin, granulocyte-colony stimulating factor, and stromal cell-derived factor-1alpha) were associated with subsequent PD. Elevation in >or=6 of 8 factors was strongly associated with shorter time to progression (P = 0.001) and was 73% specific and 100% sensitive for PD. Increasing growth-related oncogene-alpha from baseline to week 6 was also associated with PD. Progression-free and overall survival were shorter in patients with HPV-negative tumors (P = 0.012 and 0.046, respectively), but no individual CAF was associated with HPV status. However, among 14 HPV-negative patients, the high-risk CAF signature was seen in all 6 patients with PD, but only 2 of 14 without PD. In conclusion, serum CAF profiling, particularly in HPV-negative patients, may be useful for identifying those at highest risk for recurrence.
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Geographic distribution of Aedes aegypti and Aedes albopictus collected from used tires in Vietnam.
J. Am. Mosq. Control Assoc.
PUBLISHED: 04-21-2010
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The spatial distribution of Aedes aegypti and Aedes albopictus in environmental and geographical zones, e.g., urban-rural, coastal-mountainous, and north-south, was investigated throughout Vietnam. Immature stages were collected from used tires along roads. The effects of regions, seasons, and the degree of urbanization on the density and the frequency were statistically analyzed. Aedes aegypti predominated in the southern and central regions, while Ae. albopictus predominated in the northern region, which may be related to climatic conditions (temperature and rainfall). Larval collection from used tires may be suitable to assess rapidly the current distribution of dengue mosquitoes for estimating health risks and implementing vector control measures.
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Plasma cytokine and angiogenic factor profiling identifies markers associated with tumor shrinkage in early-stage non-small cell lung cancer patients treated with pazopanib.
Cancer Res.
PUBLISHED: 03-09-2010
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There is an unmet need for pharmacodynamic and predictive biomarkers for antiangiogenic agents. Recent studies have shown that soluble vascular endothelial growth factor receptor 2 (sVEGFR2), VEGF, and several other soluble factors may be modulated by VEGF pathway inhibitors. We conducted a broad profiling of cytokine and angiogenic factors (CAF) to investigate the relationship between baseline CAF levels, CAF changes during treatment, and tumor shrinkage in early-stage non-small cell lung cancer (NSCLC) patients treated with pazopanib, an oral angiogenesis inhibitor targeting VEGFR, platelet-derived growth factor receptor, and c-kit. Plasma samples were collected before treatment and on the last day of therapy from 33 patients with early-stage NSCLC participating in a single-arm phase II trial. Levels of 31 CAFs were measured by suspension bead multiplex assays or ELISA and correlated with change in tumor volume. Pazopanib therapy was associated with significant changes of eight CAFs; sVEGFR2 showed the largest decrease, whereas placental growth factor underwent the largest increase. Increases were also observed in stromal cell-derived factor-1alpha, IP-10, cutaneous T-cell-attracting chemokine, monokine induced by IFN-gamma, tumor necrosis factor-related apoptosis-inducing ligand, and IFN-alpha. Posttreatment changes in plasma sVEGFR2 and interleukin (IL)-4 significantly correlated with tumor shrinkage. Baseline levels of 11 CAFs significantly correlated with tumor shrinkage, with IL-12 showing the strongest association. Using multivariate classification, a baseline CAF signature consisting of hepatocyte growth factor and IL-12 was associated with tumor response to pazopanib and identified responding patients with 81% accuracy. These data suggest that CAF profiling may be useful for identifying patients likely to benefit from pazopanib, and merit further investigation in clinical trials.
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New insights into the effect of medium-chain-length lactones on yeast membranes. Importance of the culture medium.
Appl. Microbiol. Biotechnol.
PUBLISHED: 03-01-2010
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In hydrophobic compounds biotechnology, medium-chain-length metabolites often perturb cell activity. Their effect is usually studied in model conditions of growth in glucose media. Here, we study whether culture on lipids has an impact on the resistance of Yarrowia lipolytica to such compounds: Cells were cultured on glucose or oleate and submitted to gamma-dodecalactone. After a 60-min exposure to 3 g L(-1), about 80% of the glucose-grown cells (yeast extract peptone dextrose (YPD) cells) had lost their cultivability, 38% their membrane integrity, and 31% their reducing capacity as shown with propidium iodide and methylene blue, respectively. For oleate-grown cells, treatment at 6 g L(-1) did not alter cultivability despite some transient loss of membrane integrity from 3 g L(-1). It was shown with diphenylhexatriene and 1-(4-trimethylammoniumphenyl)-6-phenyl-1,3,5-hexatriene that oleate-grown cells had membranes more fluid and less sensitive to the lactone-induced fluidization. Analyses revealed also higher contents of ergosterol but, for YPD- and minimum-oleate-grown cells (YNBO cells), the addition of lactone provoked a decrease in the concentration of ergosterol in a way similar to the depletion by methyl-beta-cyclodextrin and an important membrane fluidization. Ergosterol depletion or incorporation increased or decreased, respectively, cell sensitivity to lactone. This study shows that the embedment of oleate moieties into membranes as well as higher concentrations of sterol play a role in the higher resistance to lactone of oleate-grown cells (YPO cells). Similar oleate-induced increase in resistance was also observed for Rhodotorula and Candida strains able to grow on oleate as the sole carbon source whereas Saccharomyces and Sporidiobolus cells were more sensitive after induction.
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Phase II trial of infusional fluorouracil, irinotecan, and bevacizumab for metastatic colorectal cancer: efficacy and circulating angiogenic biomarkers associated with therapeutic resistance.
J. Clin. Oncol.
PUBLISHED: 12-14-2009
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We investigated the efficacy of fluorouracil (FU), leucovorin, irinotecan, and bevacizumab (FOLFIRI + B) in a phase II trial in patients previously untreated for metastatic colorectal cancer (mCRC), and changes during treatment in plasma cytokines and angiogenic factors (CAFs) as potential markers of treatment response and therapeutic resistance.
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Distinct patterns of cytokine and angiogenic factor modulation and markers of benefit for vandetanib and/or chemotherapy in patients with non-small-cell lung cancer.
J. Clin. Oncol.
PUBLISHED: 11-30-2009
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There is an unmet need for biomarkers for identifying patients likely to benefit from anticancer treatments, selecting dose, and understanding mechanisms of resistance. Plasma vascular endothelial growth factor (VEGF) and soluble VEGF receptor 2 (sVEGFR-2) are known to be modulated by VEGF pathway inhibitors. It is unknown whether chemotherapy or VEGFR inhibitor/chemotherapy combinations induce changes in these or other cytokines and angiogenic factors (CAFs) and whether such changes could be markers of benefit.
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Bridging therapy in the perioperative management of patients with drug-eluting stents.
Rev Cardiovasc Med
PUBLISHED: 11-02-2009
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Patients with drug-eluting stents appear to be at increased risk of thrombosis beyond 30 days (late) or even 1 year (very late) after stent placement. Patients with recent placement of drug-eluting stents who are receiving dual-antiplatelet therapy pose a challenge in the perioperative period. Current guidelines recommend discontinuation of clopidogrel 5 to 7 days prior to surgery or invasive procedures to prevent bleeding complications. When a patient with a drug-eluting stent is off of clopidogrel, he or she is at risk of stent thrombosis, even during treatment with anticoagulants, such as intravenous heparin. There are currently no universal recommendations for decreasing the risk of stent thrombosis. We herein outline a strategy involving the use of glycoprotein IIb/IIIa inhibitors as "bridging therapy" during the high-risk perioperative period and report on 8 patients who successfully underwent bridging therapy with no adverse cardiac outcomes (death, myocardial infarction, or stent thrombosis) or bleeding complications.
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VeriStrat classifier for survival and time to progression in non-small cell lung cancer (NSCLC) patients treated with erlotinib and bevacizumab.
Lung Cancer
PUBLISHED: 10-26-2009
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We applied an established and commercially available serum proteomic classifier for survival after treatment with erlotinib (VeriStrat) in a blinded manner to pretreatment sera obtained from recurrent advanced NSCLC patients before treatment with the combination of erlotinib plus bevacizumab. We found that VeriStrat could classify these patients into two groups with significantly better or worse outcomes and may enable rational selection of patients more likely to benefit from this costly and potentially toxic regimen.
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Brain cortical mapping by simultaneous recording of functional near infrared spectroscopy and electroencephalograms from the whole brain during right median nerve stimulation.
Brain Topogr
PUBLISHED: 08-12-2009
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To investigate relationships between hemodynamic responses and neural activities in the somatosensory cortices, hemodynamic responses by near infrared spectroscopy (NIRS) and electroencephalograms (EEGs) were recorded simultaneously while subjects received electrical stimulation in the right median nerve. The statistical significance of the hemodynamic responses was evaluated by a general linear model (GLM) with the boxcar design matrix convoluted with Gaussian function. The resulting NIRS and EEGs data were stereotaxically superimposed on the reconstructed brain of each subject. The NIRS data indicated that changes in oxy-hemoglobin concentration increased at the contralateral primary somatosensory (SI) area; responses then spread to the more posterior and ipsilateral somatosensory areas. The EEG data indicated that positive somatosensory evoked potentials peaking at 22 ms latency (P22) were recorded from the contralateral SI area. Comparison of these two sets of data indicated that the distance between the dipoles of P22 and NIRS channels with maximum hemodynamic responses was less than 10 mm, and that the two topographical maps of hemodynamic responses and current source density of P22 were significantly correlated. Furthermore, when onset of the boxcar function was delayed 5-15 s (onset delay), hemodynamic responses in the bilateral parietal association cortices posterior to the SI were more strongly correlated to electrical stimulation. This suggests that GLM analysis with onset delay could reveal the temporal ordering of neural activation in the hierarchical somatosensory pathway, consistent with the neurophysiological data. The present results suggest that simultaneous NIRS and EEG recording is useful for correlating hemodynamic responses to neural activity.
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A phase II study of Lonafarnib (SCH66336) in patients with chemorefractory, advanced squamous cell carcinoma of the head and neck.
Am. J. Clin. Oncol.
PUBLISHED: 05-13-2009
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Treatment options for recurrent squamous cell carcinoma of the head and neck (SCCHN) following platinum-based therapy are limited. Lonafarnib is a potent, specific inhibitor of farnesyl transferase that demonstrated marked antitumor activity as monotherapy in treatment-naive SCCHN in a phase Ib study. A phase II study of lonafarnib was conducted to determine its efficacy and safety in patients with recurrent, platinum-refractory SCCHN.
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Classification by mass spectrometry can accurately and reliably predict outcome in patients with non-small cell lung cancer treated with erlotinib-containing regimen.
J Thorac Oncol
PUBLISHED: 05-01-2009
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Although many lung cancers express the epidermal growth factor receptor and the vascular endothelial growth factor, only a small fraction of patients will respond to inhibitors of these pathways. Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MS) has shown promise in biomarker discovery, potentially allowing the selection of patients who may benefit from such therapies. Here, we use a matrix-assisted laser desorption/ionization MS proteomic algorithm developed from a small dataset of erlotinib-bevacizumab treated patients to predict the clinical outcome of patients treated with erlotinib alone.
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Circulating biomarkers for vascular endothelial growth factor inhibitors in renal cell carcinoma.
Cancer
PUBLISHED: 04-30-2009
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In recent years, there has been significant progress in the clinical development and application of antiangiogenic therapies in renal cell carcinomas, particularly inhibitors of the vascular endothelial growth factor (VEGF) pathway. Despite this progress, no validated methods are currently available for identifying which patients are most likely to respond to treatment or experience toxic effects, selecting the optimal dose, or determining whether the intended molecular target has been effectively inhibited. However, recent studies have suggested that some of the biomarkers currently under investigation in clear cell renal cell carcinoma for VEGF pathway inhibitors are promising. These biomarkers include circulating proangiogenic factors and receptors; markers of hypoxia and endothelial damage; and cellular populations in peripheral blood, such as circulating endothelial cells. Further preclinical and translational validation studies are still needed to determine their practical utility in the clinical setting.
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Distinct biological roles for the notch ligands Jagged-1 and Jagged-2.
J. Biol. Chem.
PUBLISHED: 04-27-2009
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Notch signaling is activated in a subset of non-small cell lung cancer cells because of overexpression of Notch3, but the role of Notch ligands has not been fully defined. On the basis of gene expression profiling of a panel of non-small cell lung cancer cell lines, we found that the predominant Notch ligands were JAG1, JAG2, DLL1, and DLL3. Given that Notch ligands reportedly have overlapping receptor binding specificities, we postulated that they have redundant biological roles. Arguing against this hypothesis, we found that JAG1 and JAG2 were differentially regulated; JAG1 expression was dependent upon epidermal growth factor receptor (EGFR) activation in HCC827 cells, which require EGFR for survival, whereas JAG2 expression was EGFR-independent in these cells. Furthermore, HCC827 cells underwent apoptosis following depletion of JAG1 but not JAG2, whereas co-culture experiments revealed that depletion of JAG2, but not JAG1, enhanced the ability of HCC827 cells to chemoattract THP-1 human monocytes. JAG2-depleted HCC827 cells expressed high levels of inflammation-related genes, including interleukin 1 (IL1) and a broad range of IL1-regulated cytokines, which was attenuated by inhibition of IL1 receptor (IL1R). Our findings suggest that JAG1 and JAG2 have distinct biological roles including a previously undiscovered role for JAG2 in regulating the expression of cytokines that can promote antitumor immunity.
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T-817MA, a neurotrophic agent, ameliorates the deficits in adult neurogenesis and spatial memory in rats infused i.c.v. with amyloid-beta peptide.
Br. J. Pharmacol.
PUBLISHED: 04-03-2009
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Adult neurogenesis occurs throughout life in the subgranular zone and the dentate gyrus of the hippocampus. Deficient neurogenesis may be responsible for deficient hippocampal functions in neurodegenerative disorders such as Alzheimers disease (AD). T-817MA [1-{3-[2-(1-Benzothiophen-5-yl)ethoxy] propyl}-3-azetidinol maleate] is a newly synthesized agent for AD treatment with neuroprotective effects against toxicity from amyloid-beta peptide (Abeta) and actions promoting neurite outgrowth in vitro. Furthermore, systemic administration of T-817MA ameliorated cognitive dysfunctions caused by neurodegeneration in a rat model of AD, induced by intracerebroventricular (i.c.v.) infusion of Abeta. The present study investigated quantitative relationships between spatial memory performance in Abeta-infused rats and hippocampal neurogenesis, and the effects of T-817MA on neuronal proliferation in vivo.
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Liposomal encapsulation of deguelin: evidence for enhanced antitumor activity in tobacco carcinogen-induced and oncogenic K-ras-induced lung tumorigenesis.
Cancer Prev Res (Phila)
PUBLISHED: 03-31-2009
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Deguelin has shown promising chemopreventive and therapeutic activities in diverse types of cancers. However, the potential side effect of deguelin over a certain dose could be the substantial hurdle in the practical application of the drug. One of the successful strategies for the use of deguelin in clinical trials could be lung-specific delivery of the drug. The present study evaluates the efficacy of liposome-encapsulated deguelin with a dose of 0.4 mg/kg, which is 10 times less than the dose (4 mg/kg) for preventive and therapeutic activities validated in previous in vivo studies. Liposomal deguelin revealed cytotoxic activity in vitro in premalignant and malignant human bronchial epithelial cells and non-small cell lung cancer cells through the same mechanistic pathway previously reported for deguelin (i.e., suppression of the heat shock protein 90 chaperone function and induction of apoptosis). Delivery of liposomal deguelin at a dose of 0.4 mg/kg by intranasal instillation resulted in markedly increased drug partitioning to the lungs compared with that of 4 mg/kg deguelin or 0.4 mg/kg liposomal deguelin administered by oral gavage. Lung-specific delivery of deguelin (0.4 mg/kg) via nasal or intratracheal instillation in a liposomal formulation also showed significant chemopreventive and therapeutic activities in 4-(methylnitrosoamino)-1-(3-pyridyl)-1-butanone/benzo(a)pyrene-treated A/J mice and K-rasLAC57Bl6/129/sv F1 mice with no detectable toxicity. Our findings support the potential use of deguelin in a liposomal formulation via lung-specific delivery to improve efficacy and to reduce the potential side effects of the agent.
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The role of the C-terminal region of cyanophycin synthetase from Nostoc ellipsosporum NE1 in its enzymatic activity and thermostability: a key function of Glu(856).
Biochim. Biophys. Acta
PUBLISHED: 03-14-2009
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The biosynthesis of cyanophycin granule polypeptides is catalyzed by cyanophycin synthetase, CphA. In this study, the role of the C-terminal region of CphA from Nostoc ellipsosporum NE1, CphA(NE1), was analyzed using a tailor-made C-terminus truncated library. The expression level of truncated CphA(NE1) in E. coli depended on the stop codons that were used. The expression vector that had the amber stop codon TAG produced more than twice amount of CphA(NE1) as a vector that contained the ochre codon TAA. CphA(NE1DeltaC45), which was truncated up to 45 amino acids at its C-terminus, retained full enzymatic activity and produced polymers. However, the removal of one additional amino acid, Glu(856), resulted in complete inactivation of CphA(NE1DeltaC46). Replacement of Glu(856) by valine or alanine confirmed the importance of this residue for the activity of CphA(NE1), as it resulted in the complete inactivation of the enzyme. In addition, thermostability analysis revealed a dramatic decrease in the thermostability of CphA(NE1) after removal of the region from Leu(867) to Leu(870). The gel filtration analysis showed that CphA(NE1Delta46C) still formed a dimer form even its enzyme activity was lost completely. These results suggest that Glu(856) is critical for CphA(NE1) catalytic activity and that the predicted alpha-helical region that ranges from Val(858) to Leu(870) is important for the thermostability of the enzyme.
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Algorithmic guided screening of drug combinations of arbitrary size for activity against cancer cells.
Mol. Cancer Ther.
PUBLISHED: 03-10-2009
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The standard treatment for most advanced cancers is multidrug therapy. Unfortunately, combinations in the clinic often do not perform as predicted. Therefore, to complement identifying rational drug combinations based on biological assumptions, we hypothesized that a functional screen of drug combinations, without limits on combination sizes, will aid the identification of effective drug cocktails. Given the myriad possible cocktails and inspired by examples of search algorithms in diverse fields outside of medicine, we developed a novel, efficient search strategy called Medicinal Algorithmic Combinatorial Screen (MACS). Such algorithms work by enriching for the fitness of cocktails, as defined by specific attributes through successive generations. Because assessment of synergy was not feasible, we developed a novel alternative fitness function based on the level of inhibition and the number of drugs. Using a WST-1 assay on the A549 cell line, through MACS, we screened 72 combinations of arbitrary size formed from a 19-drug pool across four generations. Fenretinide, suberoylanilide hydroxamic acid, and bortezomib (FSB) was the fittest. FSB performed up to 4.18 SD above the mean of a random set of cocktails or "too well" to have been found by chance, supporting the utility of the MACS strategy. Validation studies showed FSB was inhibitory in all 7 other NSCLC cell lines tested. It was also synergistic in A549, the one cell line in which this was evaluated. These results suggest that when guided by MACS, screening larger drug combinations may be feasible as a first step in combination drug discovery in a relatively small number of experiments.
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A phase 2 study of cetuximab in combination with docetaxel in chemotherapy-refractory/resistant patients with advanced nonsmall cell lung cancer.
Cancer
PUBLISHED: 02-12-2009
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Cetuximab in combination with docetaxel was examined in chemotherapy-refractory/resistant patients with advanced nonsmall-cell lung cancer (NSCLC) to determine response rate, survival, safety, and pharmacokinetics (PK).
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High-dose fenretinide in oral leukoplakia.
Cancer Prev Res (Phila)
PUBLISHED: 01-14-2009
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We previously showed that low-dose fenretinide (200 mg/d) had limited activity in retinoid-resistant oral leukoplakia (34% response rate) possibly because serum drug levels were insufficient to induce retinoid receptor-independent apoptosis. Therefore, we designed the single-arm phase II trial reported here to investigate whether higher-dose fenretinide would improve leukoplakia response over that of our previous study. Leukoplakia patients received fenretinide (900 mg/m(2) twice daily) in four 3-week cycles (1 week on drug followed by 2 weeks off). At week 12, clinical responses were determined and blood samples were collected for serum drug level assessments. A planned interim futility analysis led to early trial closure after the initial 15 (of 25 planned) patients because only 3 (20%) had a partial response (stopping rule:
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Identifying intracellular Staphylococcus aureus in chronic rhinosinusitis: a direct comparison of techniques.
Am J Rhinol Allergy
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The emerging concept of intracellular pathogens such as Staphylococcus aureus playing a role in chronic rhinosinusitis (CRS) has led to the development of numerous imaging techniques for their identification. Traditional methods of bacterial culture are not effective at localizing bacteria to the surface or within tissue samples. The aim of this study was to develop and validate a novel imaging technique using confocal scanning laser microscopy (CSLM) coupled with a fluorescence in situ hybridization (FISH) probe and nucleic acid counterstain (propidium iodide [PI]) that allows for simultaneous analysis of S. aureus intracellular status and surface biofilm within whole mucosal samples.
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Neuronal responses to face-like stimuli in the monkey pulvinar.
Eur. J. Neurosci.
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The pulvinar nuclei appear to function as the subcortical visual pathway that bypasses the striate cortex, rapidly processing coarse facial information. We investigated responses from monkey pulvinar neurons during a delayed non-matching-to-sample task, in which monkeys were required to discriminate five categories of visual stimuli [photos of faces with different gaze directions, line drawings of faces, face-like patterns (three dark blobs on a bright oval), eye-like patterns and simple geometric patterns]. Of 401 neurons recorded, 165 neurons responded differentially to the visual stimuli. These visual responses were suppressed by scrambling the images. Although these neurons exhibited a broad response latency distribution, face-like patterns elicited responses with the shortest latencies (approximately 50 ms). Multidimensional scaling analysis indicated that the pulvinar neurons could specifically encode face-like patterns during the first 50-ms period after stimulus onset and classify the stimuli into one of the five different categories during the next 50-ms period. The amount of stimulus information conveyed by the pulvinar neurons and the number of stimulus-differentiating neurons were consistently higher during the second 50-ms period than during the first 50-ms period. These results suggest that responsiveness to face-like patterns during the first 50-ms period might be attributed to ascending inputs from the superior colliculus or the retina, while responsiveness to the five different stimulus categories during the second 50-ms period might be mediated by descending inputs from cortical regions. These findings provide neurophysiological evidence for pulvinar involvement in social cognition and, specifically, rapid coarse facial information processing.
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What is Visualize?

JoVE Visualize is a tool created to match the last 5 years of PubMed publications to methods in JoVE's video library.

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We use abstracts found on PubMed and match them to JoVE videos to create a list of 10 to 30 related methods videos.

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In developing our video relationships, we compare around 5 million PubMed articles to our library of over 4,500 methods videos. In some cases the language used in the PubMed abstracts makes matching that content to a JoVE video difficult. In other cases, there happens not to be any content in our video library that is relevant to the topic of a given abstract. In these cases, our algorithms are trying their best to display videos with relevant content, which can sometimes result in matched videos with only a slight relation.