CXCR4-CCR5: a couple modulating T cell functions.

abstract：:Meiotic mutant (2n) gametes formed by first-division restitution without crossover (FDR-NCO) are expected to be superior to FDR with crossover (FDR-CO) because they transmit to the progeny, without disruption by recombination, almost 100% of the parental genotype. FDR-CO transfers approximately 80% of the parental het...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Buso JA,Boiteux LS,Tai GC,Peloquin SJ

更新日期：1999-02-16 00:00:00

abstract：:Methicillin-resistant Staphylococcus aureus (MRSA) represents a serious threat to the health of hospitalized patients. Attempts to reduce the spread of MRSA have largely depended on hospital hygiene and patient isolation. These measures have met with mixed success: although some countries have almost eliminated MRSA o...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Cooper BS,Medley GF,Stone SP,Kibbler CC,Cookson BD,Roberts JA,Duckworth G,Lai R,Ebrahim S

更新日期：2004-07-06 00:00:00

abstract：:Awareness that our planet is a self-supporting biosphere with sunlight as its major source of energy for life has resulted in a long-term historical fascination with the workings of self-supporting ecological systems. However, the studies of such systems have never entered the canon of ecological or evolutionary tools...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Rillig MC,Antonovics J

更新日期：2019-06-04 00:00:00

abstract：:Hitherto it has not been possible to obtain spore and stalk cell differentiation of the cellular slime molds in submerged cultures. It is shown here that cells, when placed in roller tubes under an atmosphere of oxygen, will form clumps and differentiate in 48-72 hr into mature spores and stalk cells. Although differe...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Sternfeld J,Bonner JT

更新日期：1977-01-01 00:00:00

abstract：:Evidence indicates that the modulatory effects of the adrenergic stress hormone epinephrine as well as several other neuromodulatory systems on memory storage are mediated by activation of beta-adrenergic mechanisms in the amygdala. In view of our recent findings indicating that the amygdala is involved in mediating t...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Quirarte GL,Roozendaal B,McGaugh JL

更新日期：1997-12-09 00:00:00

abstract：:Mouse beta-globin in encoded in a discontinuous structural gene interrupted by a 550-base pair intervening sequence of DNA. Correspondingly, the mature beta-globin mRNA appears to be synthesized via a 15S precursor, the length of which roughly equals the total length of the coding and intervening sequences of the beta...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Tilghman SM,Curtis PJ,Tiemeier DC,Leder P,Weissmann C

更新日期：1978-03-01 00:00:00

abstract：:Infections caused by drug-resistant bacteria are a major problem worldwide. Carbapenem-resistant Klebsiella pneumoniae, most notably isolates classified as multilocus sequence type (ST) 258, have emerged as an important cause of hospital deaths. ST258 isolates are predominantly multidrug resistant, and therefore infec...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Deleo FR,Chen L,Porcella SF,Martens CA,Kobayashi SD,Porter AR,Chavda KD,Jacobs MR,Mathema B,Olsen RJ,Bonomo RA,Musser JM,Kreiswirth BN

更新日期：2014-04-01 00:00:00

abstract：:RNA is involved in a variety of chromatin modification events, ranging from large-scale structural rearrangements to subtle local affects. Here, we extend the evidence for RNA-chromatin interactions to the centromere core. The data indicate that maize centromeric retrotransposons (CRMs) and satellite repeats (CentC) a...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Topp CN,Zhong CX,Dawe RK

更新日期：2004-11-09 00:00:00

abstract：:The calcium-activated K(+) channel KCa3.1 plays an important role in T lymphocyte Ca(2+) signaling by helping to maintain a negative membrane potential, which provides an electrochemical gradient to drive Ca(2+) influx. To assess the role of KCa3.1 channels in lymphocyte activation in vivo, we studied T cell function ...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Di L,Srivastava S,Zhdanova O,Ding Y,Li Z,Wulff H,Lafaille M,Skolnik EY

更新日期：2010-01-26 00:00:00

abstract：:Bacterial intracellular symbiosis (endosymbiosis) is widespread in nature and impacts many biological processes. In holometabolous symbiotic insects, metamorphosis entails a complete and abrupt internal reorganization that creates a constraint for endosymbiont transmission from larvae to adults. To assess how endosymb...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Maire J,Parisot N,Galvao Ferrarini M,Vallier A,Gillet B,Hughes S,Balmand S,Vincent-Monégat C,Zaidman-Rémy A,Heddi A

更新日期：2020-08-11 00:00:00

abstract：:Topological mechanical metamaterials are artificial structures whose unusual properties are protected very much like their electronic and optical counterparts. Here, we present an experimental and theoretical study of an active metamaterial--composed of coupled gyroscopes on a lattice--that breaks time-reversal symmet...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Nash LM,Kleckner D,Read A,Vitelli V,Turner AM,Irvine WT

更新日期：2015-11-24 00:00:00

abstract：:We have used electron microscopy to examine freshly isolated Salmonella typhimurium and Escherichia coli basal flagellar fragments, purified without resort to extremes of pH or ionic strength. Such fragments contain the large bell-like basal structures visualized recently in freeze-substituted or fixed preparations. W...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Khan IH,Reese TS,Khan S

更新日期：1992-07-01 00:00:00

abstract：:Transcriptional regulation by nuclear hormone receptors is thought to involve interactions with putative cofactors that may potentiate receptor function. Here we show that human thyroid hormone receptor alpha purified from HeLa cells grown in the presence of thyroid hormone (T3) is associated with a group of distinct ...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Fondell JD,Ge H,Roeder RG

更新日期：1996-08-06 00:00:00

abstract：:Multisystem Inflammatory Syndrome in Children (MIS-C) associated with COVID-19 is a newly recognized condition in children with recent severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. These children and adult patients with severe hyperinflammation present with a constellation of symptoms that st...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Cheng MH,Zhang S,Porritt RA,Noval Rivas M,Paschold L,Willscher E,Binder M,Arditi M,Bahar I

更新日期：2020-10-13 00:00:00

abstract：:Serine is the only amino acid that is encoded by two disjoint codon sets so that a tandem substitution of two nucleotides is required to switch between the two sets. Previously published evidence suggests that, for the most evolutionarily conserved serines, the codon set switch occurs by simultaneous substitution of t...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Rogozin IB,Belinky F,Pavlenko V,Shabalina SA,Kristensen DM,Koonin EV

更新日期：2016-11-15 00:00:00

abstract：:Cisplatin is a chemotherapeutic drug used to treat a variety of cancers. Both intrinsic and acquired resistance to cisplatin, as well as toxicity, limit its effectiveness. Molecular mechanisms that underlie cisplatin resistance are poorly understood. Here we demonstrate that deletion of the yeast CTR1 gene, which enco...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Ishida S,Lee J,Thiele DJ,Herskowitz I

更新日期：2002-10-29 00:00:00

abstract：:A study has been made of Cauchy's problem for a class of abstract parabolic differential equations. Our study is based upon a transformation that maps solutions of second-order abstract Cauchy problems into solutions of first-order. This is a preliminary report on some of the results obtained. These results include (1...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Donaldson JA

更新日期：1971-09-01 00:00:00

abstract：:Despite the enormous theoretical attention given to the evolutionary consequences of sexual reproduction, the validity of the key assumptions on which the theory depends rarely has been evaluated. It is often argued that a reduced ability to purge deleterious mutations condemns asexual lineages to an early extinction....

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Omilian AR,Cristescu ME,Dudycha JL,Lynch M

更新日期：2006-12-05 00:00:00

abstract：:O-linked N-acetylglucosamine (GlcNAc) transferase (OGT) is the only known enzyme that catalyzes the O-GlcNAcylation of proteins at the Ser or Thr side chain hydroxyl group. OGT participates in transcriptional and epigenetic regulation, and dysregulation of OGT has been implicated in diseases such as cancer. However, t...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Chu CS,Lo PW,Yeh YH,Hsu PH,Peng SH,Teng YC,Kang ML,Wong CH,Juan LJ

更新日期：2014-01-28 00:00:00

abstract：:We report the direct measurement of thermodynamic properties of colloidal hard spheres by optical microscopy. By using confocal microscopy, we obtain three-dimensional snapshots of a colloidal hard-sphere suspension over a wide range of densities. From these snapshots, the available volume to insert an additional sphe...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Dullens RP,Aarts DG,Kegel WK

更新日期：2006-01-17 00:00:00

abstract：:Bone morphogenetic protein 4 (BMP-4) induces ventral mesoderm but represses dorsal mesoderm formation in Xenopus embryos. We show that BMP-4 inhibits two signaling pathways regulating dorsal mesoderm formation, the induction of dorsal mesoderm (Spemann organizer) and the dorsalization of ventral mesoderm. Ectopic expr...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Re'em-Kalma Y,Lamb T,Frank D

更新日期：1995-12-19 00:00:00

abstract：:For the purpose of clarifying the magneto-orientation mechanism of several biological membrane systems, xylene-suspended thin-layered single crystals of lecithin, which is a major component of membranes, were subjected to magnetic fields of various strengths, and the orientation behavior of the crystals was analyzed. ...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Sakurai I,Kawamura Y,Ikegami A,Iwayanagi S

更新日期：1980-12-01 00:00:00

abstract：:Phycobilisomes isolated from eight different species of cyanobacteria contain in addition to the light-harvesting phycobiliproteins, a small number of colorless polypeptides with molecular weights higher than those of the chromopolypeptide subunits of the phycobiliproteins. In the phycobilisomes of the species examin...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： de Marsac NT,Cohen-bazire G

更新日期：1977-04-01 00:00:00

abstract：:The ability of beta cells to endure assaults may be relevant in the development of insulin-dependent diabetes mellitus. This study examines the susceptibility of human pancreatic islets to agents that are cytotoxic for rodent beta cells--i.e., sodium nitroprusside (NP, a nitric oxide donor), streptozotocin (SZ), or al...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Eizirik DL,Pipeleers DG,Ling Z,Welsh N,Hellerström C,Andersson A

更新日期：1994-09-27 00:00:00

abstract：:The bacteriophage T4-encoded RegB endoribonuclease is produced during the early stage of phage development and targets mostly (but not exclusively) the Shine-Dalgarno sequences of early genes. In this work, we show that the degradation of RegB-cleaved mRNAs depends on a functional T4 polynucleotide kinase/phosphatase ...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Durand S,Richard G,Bontems F,Uzan M

更新日期：2012-05-01 00:00:00

abstract：:An extracellular patch electrode was used to record ionic currents from individual complement-induced channels in the membranes of antibody-coated skeletal muscle. The amplitude of the single-channel currents leads to an estimate of 90 pS for the unit conductance. The kinetics of channel opening and closing show marke...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Jackson MB,Stephens CL,Lecar H

更新日期：1981-10-01 00:00:00

abstract：:Understanding the molecular mechanisms of osmolyte protection in protein stability has proved to be challenging. In particular, little is known about the role of osmolytes in the structure of the unfolding transition state of a protein, the main determinant of its dynamics. We have developed an experimental protocol t...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Dougan L,Genchev GZ,Lu H,Fernandez JM

更新日期：2011-06-14 00:00:00

abstract：:Most proteins are in equilibrium with partially and globally unfolded conformations. In contrast, kinetically stable proteins (KSPs) are trapped by an energy barrier in a specific state, unable to transiently sample other conformations. Among many potential roles, it appears that kinetic stability (KS) is a feature us...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Xia K,Manning M,Hesham H,Lin Q,Bystroff C,Colón W

更新日期：2007-10-30 00:00:00

abstract：:Myosins, a large family of actin-based motors, have one or two heavy chains with one or more light chains associated with each heavy chain. The heavy chains have a (generally) N-terminal head domain with an ATPase and actin-binding site, followed by a neck domain to which the light chains bind, and a C-terminal tail d...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Korn ED

更新日期：2000-11-07 00:00:00

abstract：:We identified previously in vitro LRP4 (low-density lipoprotein receptor-related protein 4) as a facilitator of the WNT (Wingless-type) antagonist sclerostin and found mutations disrupting this function to be associated with high bone mass in humans similar to patients lacking sclerostin. To further delineate the role...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Chang MK,Kramer I,Huber T,Kinzel B,Guth-Gundel S,Leupin O,Kneissel M

更新日期：2014-12-02 00:00:00