14 research outputs found
Phase separation of signaling molecules promotes T cell receptor signal transduction
No full textAuthor Posting. © The Author(s), 2016. This is the author's version of the work. It is posted here by permission of American Association for the Advancement of Science for personal use, not for redistribution. The definitive version was published in Science 352 (2016): 595-599, doi:10.1126/science.aad9964.Activation of various cell surface receptors triggers the reorganization of downstream signaling
molecules into micron- or submicron-sized clusters. However, the functional consequences of
such clustering has been unclear. We biochemically reconstituted a 12-component signaling
pathway on model membranes, beginning with T cell receptor (TCR) activation and ending with
actin assembly. When TCR phoshophorylation was triggered, downstream signaling proteins
spontaneously separated into liquid-like clusters that promoted signaling outputs both in vitro
and in human Jurkat T cells. Reconstituted clusters were enriched in kinases but excluded
phosphatases, and enhanced actin filament assembly by recruiting and organizing actin
regulators. These results demonstrate that protein phase separation can create a distinct physical
and biochemical compartment that facilitates signaling.This work was supported by the HCIA
program of HHMI, the NIH (R01-GM56322 to M.K.R.) and Welch Foundation (I–1544 to
M.K.R.). X.S. was supported by CRI Irvington postdoctoral fellowship. J.A.D. was supported by
NRSA F32 award 5-F32-DK101188. E.H. was supported as a fellow of the Leukemia and
Lymphoma Society. J.O. was supported by funds from Tobacco-Related Disease Research
Program of the University of California (19FT-0090).2016-10-0
Evaluation of a modified double-disc synergy test for detection of extended spectrum β-lactamases in AMPC β-lactamase-producing proteus mirabilis
No full textThe detection of extended-spectrum β-lactamases (ESBLs) in
gram-negative bacteria that produce AmpC β-lactamases is
problematic. In the present study, the performance of modified
double-disc synergy test (MDDST) that employs a combination of cefepime
and piperacillin-tazobactam for the detection of proteus mirabilis
producing extended spectrum and AmpC β-lactamases was evaluated
and compared with double-disc synergy test (DDST) and NCCLS phenotypic
disc confirmatory test (NCCLS-PDCT). A total of 90 clinical isolates of
P. mirabilis , which met the CLSI (Clinical and Laboratory Standards
Institute) screening criteria that these had broth microdilution (BMD)
MIC of ≥2 mg/mL for at least one extended spectrum cephalosporin
[ceftazidime (CAZ), cefotaxime (CTX) and cefpodoxime], were selected
for the study. MDDST detected ESBLs in 40/90 of the isolates, whereas
DDST detected ESBLs in only 25 isolates. NCCLS-PDCT could detect ESBLs
in 39 isolates using CAZ and CAZ + clavulanic acid (CLA) combination,
whereas CTX and CTX + CLA combination could detect only 37 isolates as
ESBL positive. As many as 34/40 ESBL positive isolates were confirmed
to be AmpC β-lactamase positive by the modified three-dimensional
test (MTDT). MDDST and NCCLS-PDCT could detect ESBLs in all the 34 AmpC
positive isolates, whereas DDST could detect ESBLs in only 19 isolates.
The study demonstrated that MDDST is superior to DDST and as sensitive
as NCCLS-PDCT. However, MDDST seems to have enhanced potential for the
detection of ESBLs in AmpC β-lactamase-producing P. mirabilis
Evaluation of a modified double-disc synergy test for detection of extended spectrum β-lactamases in AMPC β-lactamase-producing proteus mirabilis
No full textThe detection of extended-spectrum β-lactamases (ESBLs) in
gram-negative bacteria that produce AmpC β-lactamases is
problematic. In the present study, the performance of modified
double-disc synergy test (MDDST) that employs a combination of cefepime
and piperacillin-tazobactam for the detection of proteus mirabilis
producing extended spectrum and AmpC β-lactamases was evaluated
and compared with double-disc synergy test (DDST) and NCCLS phenotypic
disc confirmatory test (NCCLS-PDCT). A total of 90 clinical isolates of
P. mirabilis , which met the CLSI (Clinical and Laboratory Standards
Institute) screening criteria that these had broth microdilution (BMD)
MIC of ≥2 mg/mL for at least one extended spectrum cephalosporin
[ceftazidime (CAZ), cefotaxime (CTX) and cefpodoxime], were selected
for the study. MDDST detected ESBLs in 40/90 of the isolates, whereas
DDST detected ESBLs in only 25 isolates. NCCLS-PDCT could detect ESBLs
in 39 isolates using CAZ and CAZ + clavulanic acid (CLA) combination,
whereas CTX and CTX + CLA combination could detect only 37 isolates as
ESBL positive. As many as 34/40 ESBL positive isolates were confirmed
to be AmpC β-lactamase positive by the modified three-dimensional
test (MTDT). MDDST and NCCLS-PDCT could detect ESBLs in all the 34 AmpC
positive isolates, whereas DDST could detect ESBLs in only 19 isolates.
The study demonstrated that MDDST is superior to DDST and as sensitive
as NCCLS-PDCT. However, MDDST seems to have enhanced potential for the
detection of ESBLs in AmpC β-lactamase-producing P. mirabilis
Effect of yttrium(Y) on structural, morphological and transport properties of CdO thin films prepared by spray pyrolysis technique
No full textCadmium oxide (CdO) and yttrium (Y) doped CdO (Y: CdO) thin films have been prepared onto glass substrate at temperature 300 °C by spray pyrolysis technique. The effects of yttrium (Y) doping on the structural, morphology, optical and electrical properties were studied systematically. The X-ray diffraction (XRD) study confirms that CdO films are polycrystalline in nature with cubic structure having lattice parameter of 0.4658 nm. Surface topographic and nano-structural analysis indicates cluster grain size and porosity decreased substantially with increase of yttrium (Y) content in CdO films. The optical transmittance exhibits excellent optical transparency, with an average transmittance of >70% in the visible range for 2 to 4% yttrium (Y) doping. The optical band gap widens in Y: CdO film from 2.24 to 2.62 eV through Burstein- Moss shift. Hall measurement confirms that material is of n type with a minimum resistivity of 4.7 × 10−4 Ω-cm with carrier concentration of 4.2 × 1021 cm−3 were achieved for 2% yttrium (Y) doping
Influence of chromium on structural, non-linear optical constants and transport properties of CdO thin films
No full textEffect of Cotton Leaf Mosaic Disease on Morphology, Yield and Fibre Characteristics of Upland Cotton in Pakistan
No full text
Unlocking the mechanical, thermodynamic and thermoelectric properties of NaSbS2: A DFT scheme
No full textThe present study focuses on the ground state mechanical, acoustic, thermodynamic and electronic transport properties of NaSbS2 polymorphs using the density functional theory (DFT) and semi-classical Boltzmann transport theory. The mechanical stability of the polymorphs is affirmed by the calculated elastic tensor. The calculated elastic properties asserted that all the polymorphs exhibit soft, brittle, anisotropic nature containing dominant covalent bonding. The 2D polar graphs are used to describe the anisotropic characteristic of the elastic parameters. The estimated value of Young's modulus and lattice thermal conductivity suggested that the polymorphs could be suitable for thermal barrier coating. Heat capacity, melting temperature, thermal conductivities, Grüneisen parameter, and thermal expansion coefficient of the polymorphs have also been studied to demonstrate thermodynamic behavior. The predicted lower values of lattice thermal conductivity declared that NaSbS2 polymorphs exhibit excellent electrical conductivity and transport properties. The estimated Seebeck coefficient (S), power factor (PF) and figure of merit (ZT) suggested that n-type triclinic and monoclinic, as well as p-type trigonal NaSbS2, are better for thermoelectric applications. The optimal carrier concentration for monoclinic structure is 1021 cm−3 for T 750 K. It is also found that the optimal carrier concentration of the trigonal is 1021 cm−3, whereas it is 1020 cm−3 for triclinic structures. Therefore, it can be stated that NaSbS2 polymorphs possess excellent thermoelectric features, making them a promising choice for thermoelectric (TE) applications
Effect of In doping on structural, morphological, optical and transport properties of CuIn x S 1−x nano-crystalline films for photovoltaic applications
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