62 research outputs found
Rejuvenated Clothes
Do you remember Aladdin\u27s conspirators trading new lamps for old? Yes, it was a fairy tale and the objects were lamps, but now transformations just as miraculous can be made in your spring wardrobe
What Goal Posts?
But, Joe, where are the goal posts? And another blossoming romance is nipped in the bud at a basketball game
Applying antibodies inside cells: Principles and recent advances in neurobiology, virology and oncology
To interfere with cell function, many scientists rely on methods that target DNA or RNA due to the ease with which they can be applied. Proteins are usually the final executors of function but are targeted only indirectly by these methods. Recent advances in targeted degradation of proteins based on proteolysis-targeting chimaeras (PROTACs), ubiquibodies, deGradFP (degrade Green Fluorescent Protein) and other approaches have demonstrated the potential of interfering directly at the protein level for research and therapy. Proteins can be targeted directly and very specifically by antibodies, but using antibodies inside cells has so far been considered to be challenging. However, it is possible to deliver antibodies or other proteins into the cytosol using standard laboratory equipment. Physical methods such as electroporation have been demonstrated to be efficient and validated thoroughly over time. The expression of intracellular antibodies (intrabodies) inside cells is another way to interfere with intracellular targets at the protein level. Methodological strategies to target the inside of cells with antibodies, including delivered antibodies and expressed antibodies, as well as applications in the research areas of neurobiology, viral infections and oncology, are reviewed here. Antibodies have already been used to interfere with a wide range of intracellular targets. Disease-related targets included proteins associated with neurodegenerative diseases such as Parkinson's disease (α-synuclein), Alzheimer's disease (amyloid-β) or Huntington's disease (mutant huntingtin [mHtt]). The applications of intrabodies in the context of viral infections include targeting proteins associated with HIV (e.g. HIV1-TAT, Rev, Vif, gp41, gp120, gp160) and different oncoviruses such as human papillomavirus (HPV), hepatitis B virus (HBV), hepatitis C virus (HCV) and Epstein-Barr virus, and they have been used to interfere with various targets related to different processes in cancer, including oncogenic pathways, proliferation, cell cycle, apoptosis, metastasis, angiogenesis or neo-antigens (e.g. p53, human epidermal growth factor receptor-2 [HER2], signal transducer and activator of transcription 3 [STAT3], RAS-related RHO-GTPase B (RHOB), cortactin, vascular endothelial growth factor receptor 2 [VEGFR2], Ras, Bcr-Abl). Interfering at the protein level allows questions to be addressed that may remain unanswered using alternative methods. This review addresses why direct targeting of proteins allows unique insights, what is currently feasible in vitro, and how this relates to potential therapeutic applications
Fault tolerant dynamic agent systems
Thesis (M. Eng.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2005.Includes bibliographical references (p. 67-68).Partial system snapshots reduce the cost per node to only depend on the size of the connected group instead of the size of the full system. These groups can be determined during system operation by using the communication patterns between nodes. The number of nodes that must rollback after a failure is limited to the size of these snapshot groups, reducing the work lost. These changes to snapshot algorithms are necessary because the cost per node for a snapshot increases and the expected time between failures decreases as the size of the system grows.by James M. Roewe.M.Eng
Rational synthesis and properties of new long-chain linear oligomeric germanium compounds
Germanium compounds with single germanium-germanium bonds contain interesting optical and electronic properties such as absorption within the UV/visible range and conductivity, which can also be seen in other heavier Group 14 oligomers. In comparison to the tin and silicon analogues, the reported methods for synthesizing the germanium compounds are minimal. The longest linear oligogermane completely characterized, including its structure, is the perphenylated pentagermane, Ge5Ph12. Due to their inherent properties, it is of interest to synthesize longer, linear oligomeric germanium compounds. It is proposed that if a long enough chain of germanium atoms is obtained, properties characteristic of polygermane species may also be achieved. Protection/deprotection strategies, using a masked Ge-H bond, were initially attempted, however only a linear pentagermane could be obtain. All products were also liquid, preventing complete characterization using X-ray crystallography.After synthetic efforts were shifted away from the protection/deprotection strategies, a successful strategy was achieved starting with a cyclic germanium species. The hexagermane Pri3Ge(GePh2)4GePri3 was synthesized in three steps from cyclic (GePh2)4 within reasonable overall yield. The hexagermane exhibits a ?max of 310 nm in its UV/visible spectrum, which is more red-shifted than any other discrete oligogermanes synthesized with six or less consecutive germanium atoms, and the DPV contained 5 consecutive, irreversible oxidation waves, the first of which was observed at 1080 mV. The hexagermane is the first discrete organogermanium compound to exhibit fluorescence, with a broad emission at 370 nm when excited at 312 nm. Crystals of the hexagermane were dichroic. Though colorless under ambient light, the hexagermane crystals appeared blue under "right" plane polarized light and pale yellow under "left" polarized light.Since 1986 when the first pentagermane was synthesized, progress has not been successful at synthesizing a longer oligogermane. A linear hexagermane has finally been synthesized and completely characterized indicating that discrete oligomeric germanium compounds have the ability to mirror properties of polymeric germanium species given enough consecutive germanium atoms
Experimental design of complement component 5a‐induced acute lung injury (C5a‐ALI): a role of CC‐chemokine receptor type 5 during immune activation by anaphylatoxin
Excessive activation of the complement system is detrimental in acute inflammatory disorders. In this study, we analyzed the role of complement‐derived anaphylatoxins in the pathogenesis of experimental acute lung injury/acute respiratory distress syndrome (ALI/ARDS) in C57BL/6J mice. Intratracheal administration of recombinant mouse complement component (C5a) caused alveolar inflammation with abundant recruitment of Ly6‐G+CD11b+ leukocytes to the alveolar spaces and severe alveolar‐capillary barrier dysfunction (C5a‐ALI; EC50[C5a] = 20 ng/g body weight). Equimolar concentrations of C3a or desarginated C5a (C5adesArg) did not induce alveolar inflammation. The severity of C5a‐ALI was aggravated in C5‐deficient mice. Depletion of Ly6‐G+ cells and use of C5aR1‐/‐ bone marrow chimeras suggested an essential role of C5aR1+ hematopoietic cells in C5a‐ALI. Blockade of PI3K/Akt and MEK1/2 kinase pathways completely abrogated lung injury. The mechanistic description is that C5a altered the alveolar cytokine milieu and caused significant release of CC‐chemokines. Mice with genetic deficiency of CC‐chemokine receptor (CCR) type 5, the common receptor of chemokine (C‐C motif) ligand (CCL) 3, CCL4, and CCL5, displayed reduced lung damage. Moreover, treatment with a CCR5 antagonist, maraviroc, was protective against C5a‐ALI. In summary, our results suggest that the detrimental effects of C5a in this model are partly mediated through CCR5 activation downstream of C5aR1, which may be evaluated for potential therapeutic exploitation in ALI/ARDS.—Russkamp, N. F., Ruemmler, R., Roewe, J., Moore, B. B., Ward, P. A., Bosmann, M. Experimental design of complement component 5a‐induced acute lung injury (C5a‐ALI): a role of CC‐chemokine receptor type 5 during immune activation by anaphylatoxin. FASEB J. 29, 3762‐3772 (2015). www.fasebj.orgPeer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/154372/1/fsb2029009014.pd
Alzheimer's disease-associated R47H TREM2 increases, but wild-type TREM2 decreases, microglial phagocytosis of synaptosomes and neuronal loss
Triggering receptor on myeloid cells 2 (TREM2) is an innate immune receptor, upregulated on the surface of microglia associated with amyloid plaques in Alzheimer's disease (AD). Individuals heterozygous for the R47H variant of TREM2 have greatly increased risk of developing AD. We examined the effects of wild-type (WT), R47H and knock-out (KO) of human TREM2 expression in three microglial cell systems. Addition of mouse BV-2 microglia expressing R47H TREM2 to primary mouse neuronal cultures caused neuronal loss, not observed with WT TREM2. Neuronal loss was prevented by using annexin V to block exposed phosphatidylserine, an eat-me signal and ligand of TREM2, suggesting loss was mediated by microglial phagocytosis of neurons exposing phosphatidylserine. Addition of human CHME-3 microglia expressing R47H TREM2 to LUHMES neuronal-like cells also caused loss compared to WT TREM2. Expression of R47H TREM2 in BV-2 and CHME-3 microglia increased their uptake of phosphatidylserine-beads and synaptosomes versus WT TREM2. Human iPSC-derived microglia with heterozygous R47H TREM2 had increased phagocytosis of synaptosomes vs common-variant TREM2. Additionally, phosphatidylserine liposomes increased activation of human iPSC-derived microglia expressing homozygous R47H TREM2 versus common-variant TREM2. Finally, overexpression of TREM2 in CHME-3 microglia caused increased expression of cystatin F, a cysteine protease inhibitor, and knock-down of cystatin F increased CHME-3 uptake of phosphatidylserine-beads. Together, these data suggest that R47H TREM2 may increase AD risk by increasing phagocytosis of synapses and neurons via greater activation by phosphatidylserine and that WT TREM2 may decrease microglial phagocytosis of synapses and neurons via cystatin F
The Iowa Homemaker vol.17, no.6
Genuinely “Big” Business by Grace McIlrath Ellis, page 1
Every Gram of Jam by Ruth Kunerth, page 2
Confessions of Shoe Salesman and Florist by Paul Montgomery and Paul Buehler, page 3
What Would You Do If by Harriet Beyer, page 4
Food Shots Are Not So Candid by Ruth Dahlberg, page 5
Yumph Invades the Formal Field by Lois Swenson, page 6
Just Skin Deep by Donna Button, page 7
On Your Own Toes by Jane Helser, page 8
Resolve to Charm by Frances Dickerson, page 9
What’s New in Home Economics edited by Marjorie Pettinger, page 10
No Peacock Tongues by Daisy Mary Kimberley, page 12
She Knows Her Turkeys by Mary Ellen Lynch, page 13
On the Airwaves by Grace Strohmeier, page 13
Science in the Kitchen, page 14
Radiation Ratings by Kay Dodds, page 15
The Gavel Strikes by Donna Button, page 16
What Goal Posts? By Jean Metcalf and Rachel Roewe, page 17
Alums Make News by Faithe Danielson, page 18
Up With the Dawn by the editor, page 2
Novel potent liposome agonists of triggering receptor expressed on myeloid cells 2 phenocopy antibody treatment in cells
The receptor Triggering Receptor Expressed on Myeloid cells 2 (TREM2) is associated with several neurodegenerative diseases including Alzheimer's Disease and TREM2 stimulation represents a novel therapeutic opportunity. TREM2 can be activated by antibodies targeting the stalk region, most likely through receptor dimerization. Endogenous ligands of TREM2 are suggested to be negatively charged apoptotic bodies, mimicked by phosphatidylserine incorporated in liposomes and other polyanionic molecules likely binding to TREM2 IgV fold. However, there has been much discrepancy in the literature on the nature of phospholipids (PLs) that can activate TREM2 and on the stability of the corresponding liposomes over time. We describe optimized liposomes as robust agonists selective for TREM2 over TREM1 in cellular system. The detailed structure/activity relationship studies of lipid polar heads indicate that negatively charged lipid heads are required for activity and we identified the shortest maximally active PL sidechain. Optimized liposomes are active on both TREM2 common variant and TREM2 R47H mutant. Activity and selectivity were further confirmed in different native TREM2 expressing cell types including on integrated cellular responses such as stimulation of phagocytic activity. Such tool agonists will be useful in further studies of TREM2 biology in cellular systems alongside antibodies, and in the design of small molecule synthetic TREM2 agonists
Acetate as a model for aspartate-based CXCR4 chemokine receptor binding of cobalt and nickel complexes of cross-bridged tetraazamacrocycles
A number of disease states including WHIM syndrome, HIV infection and cancer have been linked to the chemokine receptor CXCR4. High-affinity CXCR4 antagonist transition metal complexes of configurationally restricted bis-tetraazamacrocyclic ligands have been identified in previous studies. Recently synthesised and structurally characterised Co2+/Co3+ and Ni2+ acetate complexes of mono-macrocycle cross-bridged ligands have been used to mimic their known coordination interaction with the aspartate side chains on binding to CXCR4. Here, X-ray crystal structures for three Co2+/Co3+ acetate complexes and five Ni2+ acetate complexes are presented and demonstrate flexibility in the mode of binding to the acetate ligand concomitantly with the requisite cis-V-configured cross-bridged tetraazamacrocyle. Complexes of the smaller Co3+ metal ion exclusively bind acetate by chelating both oxygens of acetate. Larger Co2+ and Ni2+ metal ions in cross-bridged tetraazamacrocycles show a clear tendency to coordinate acetate in a monodentate fashion with a coordinated water molecule completing the octahedral coordination sphere. However, in unbridged tetraazamacrocycle acetate structures reported in the literature, the coordination preference is to chelate both acetate oxygens. We conclude that the short ethylene cross-bridge restricts the equatorial bulk of the macrocycle, prompting the metal ion to fill the equator with the larger monodentate acetate plus water ligand set. In unbridged ligand examples, the flexible macrocycle expands equatorially and generally only allows chelation of the sterically smaller acetate alone. These results provide insight for generation of optimised bis-macrocyclic CXCR4 antagonists utilising cobalt and nickel ions
- …