253 research outputs found
THE REQUIREMENT OF OVALBUMIN FOR THE GROWTH OF GROUP A HEMOLYTIC STREPTOCOCCUS IN A SYNTHETIC MEDIUM
Complete Genome Sequence of mcr-9 containing Leclercia adecarboxylata
Here, we provide the genome sequence of a Leclercia adecarboxylata isolated from a screen of an environmental bacterial isolate library for resistance to the plant flavonoid berberine. We detected the colistin resistance gene mcr-9, located on an IncFII(pECLA) plasmid
Complete genome sequence of mcr-9 containing Leclercia adecarboxylata
Here, we provide the genome sequence of a Leclercia adecarboxylata isolated from a screen of an environmental bacterial isolate library for resistance to the plant flavonoid berberine. We detected the colistin resistance gene mcr-9, located on an IncFII(pECLA) plasmid
Synthesis, Characterization, and Crystal Structure of the (η5-C5Ph5)Cr(CO)3 Radical
The reaction between Cr(CO)6 and Na(C5Ph5 ) in refluxing diglyme yields [Na(diglyme)3/2][(C5Ph5)Cr(CO)3], 1. Metathesis of 1 with [Ph3P=N=PPh3 ]Cl in CH2Cl2 yields [Ph3P=N=PPh3][(C5Ph5)Cr(CO)3], 2. Oxidation of 1 by AgBF4 in cold THF under an argon atmosphere produces (C5Ph5)Cr(CO)3, 3. Complexes 2 and 3 form a redox pair connected by a quasireversible one-electron process, E0 = -0.69 V vs ferrocene in CH2Cl2, E0 = -0.50 V in CH3CN, ks = 0.12 cm/s. ESR spectra of (C5Ph5)Cr(CO)3 in toluene at 90 K gave a rhombic g-tensor with components 2.1366, 2.0224, and 1.9953, consistent with the expected low-spin d5 electronic configuration. The largest g-tensor component was significantly temperature dependent, suggesting an equilibrium between conformations with 2A´ and 2A˝ ground states. Crystal structures of [Ph3P=N=PPh3][(C5Ph5)Cr(CO)3] and (C5Ph5)Cr(CO)3 were obtained
Heavy Alcohol Use Is Associated With Worse Retention in HIV Care
Poor retention in HIV care is associated with worse clinical outcomes and increased HIV transmission. We examined the relationship between self-reported alcohol use, a potentially modifiable behavior, and retention
Cloning, Expression, and Purification of Histidine-Tagged Escherichia coli Dihydrodipicolinate Reductase
This work was supported in part by funds from an Oklahoma State Regent Grant for Higher Education (021606), P20RR016478 grant from the National Center for Research Resources (NCRR) a component of National Institute of Health (NIH), and a grant from the University of Central Oklahoma office of Research and Grants to L.C.The enzyme dihydrodipicolinate reductase (DHDPR) is a component of the lysine biosynthetic pathway in bacteria and higher plants. DHDPR catalyzes the NAD(P)H dependent reduction of 2,3-dihydrodipicolinate to the cyclic imine L-2,3,4,5,-tetrahydropicolinic acid. The dapB gene that encodes dihydrodipicolinate reductase has previously been cloned, but the expression of the enzyme is low and the purification is time consuming. Therefore the E. coli dapB gene was cloned into the pET16b vector to improve the protein expression and simplify the purification. The dapB gene sequence was utilized to design forward and reverse oligonucleotide primers that were used to PCR the gene from Escherichia coli genomic DNA. The primers were designed with NdeI or BamHI restriction sites on the 5’and 3’ terminus respectively. The PCR product was sequenced to confirm the identity of dapB. The gene was cloned into the expression vector pET16b through NdeI and BamHI restriction endonuclease sites. The resulting plasmid containing dapB was transformed into the bacterial strain BL21 (DE3). The transformed cells were utilized to grow and express the histidine-tagged reductase and the protein was purified using Ni-NTA affinity chromatography. SDS/PAGE gel analysis has shown that the protein was 95% pure and has approximate subunit molecular weight of 28 kDa. The protein purification is completed in one day and 3 liters of culture produced approximately 40–50 mgs of protein, an improvement on the previous protein expression and multistep purification.Yeshttp://www.plosone.org/static/editorial#pee
Unified treatment algorithm for the management of crotaline snakebite in the United States: results of an evidence-informed consensus workshop
<p>Abstract</p> <p>Background</p> <p>Envenomation by crotaline snakes (rattlesnake, cottonmouth, copperhead) is a complex, potentially lethal condition affecting thousands of people in the United States each year. Treatment of crotaline envenomation is not standardized, and significant variation in practice exists.</p> <p>Methods</p> <p>A geographically diverse panel of experts was convened for the purpose of deriving an evidence-informed unified treatment algorithm. Research staff analyzed the extant medical literature and performed targeted analyses of existing databases to inform specific clinical decisions. A trained external facilitator used modified Delphi and structured consensus methodology to achieve consensus on the final treatment algorithm.</p> <p>Results</p> <p>A unified treatment algorithm was produced and endorsed by all nine expert panel members. This algorithm provides guidance about clinical and laboratory observations, indications for and dosing of antivenom, adjunctive therapies, post-stabilization care, and management of complications from envenomation and therapy.</p> <p>Conclusions</p> <p>Clinical manifestations and ideal treatment of crotaline snakebite differ greatly, and can result in severe complications. Using a modified Delphi method, we provide evidence-informed treatment guidelines in an attempt to reduce variation in care and possibly improve clinical outcomes.</p
Distinct tau prion strains propagate in cells and mice and define different tauopathies
Prion-like propagation of tau aggregation might underlie the stereotyped progression of neurodegenerative tauopathies. True prions stably maintain unique conformations (“strains”) in vivo that link structure to patterns of pathology. We now find that tau meets this criterion. Stably expressed tau repeat domain indefinitely propagates distinct amyloid conformations in a clonal fashion in culture. Reintroduction of tau from these lines into naive cells reestablishes identical clones. We produced two strains in vitro that induce distinct pathologies in vivo as determined by successive inoculations into three generations of transgenic mice. Immunopurified tau from these mice recreates the original strains in culture. We used the cell system to isolate tau strains from 29 patients with 5 different tauopathies, finding that different diseases are associated with different sets of strains. Tau thus demonstrates essential characteristics of a prion. This might explain the phenotypic diversity of tauopathies and could enable more effective diagnosis and therapy
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