1,104 research outputs found
Bioassay-guided isolation and identification of antimicrobial compounds from thyme essential oil by means of overpressured layer chromatography, bioautography and GC-MS
A simple method is described for efficient isolation of compounds having an antibacterial effect.
Two thyme (Thymus vulgaris) essential oils, obtained from the market, were chosen as
prospective materials likely to feature several bioactive components when examined by thin layer
chromatography coupled with direct bioautography as a screening method. The newly developed
infusion overpressured layer chromatographic separation method coupled with direct
bioautography assured that only the active components were isolated by means of overrun
overpressured layer chromatography with online detection and fractionation. Each of the 5
collected fractions represented one of the five antimicrobial essential oil components designated
at the screening. The purity and the activity of the fractions were confirmed with chromatography
coupled various detection methods (UV, vanillin-sulphuric acid reagent, direct bioautography).
The antibacterial components were identified with GC-MS as thymol, carvacrol, linalool, diethylphthalate,
and alpha-terpineol. The oil component diethyl-phthalate is an artificial compound,
used as plasticizer or detergent bases in the industry. Our results support that exploiting its
flexibility and the possible hyphenations, overpressured layer chromatography is especially
attractive for isolation of antimicrobial components from various matrixes
Cognitive function in a randomized trial of evolocumab
Inga StuġÄna as well as a complete list of investigators is provided in the Supplementary Appendix, available at NEJM.org. https://www.nejm.org/doi/suppl/10.1056/NEJMoa1701131/suppl_file/nejmoa1701131_appendix.pdf Funding Information: (Funded by Amgen; EBBINGHAUS ClinicalTrials.gov number, NCT02207634.) Supported by Amgen. We thank Sarah T. Farias, Ph.D., at UC Davis Health for providing the English-language and translated versions of the Everyday Cognition (ECog) tool. Publisher Copyright: Copyright Š 2017 Massachusetts Medical Society.BACKGROUND: Findings from clinical trials of proprotein convertase subtilisinâkexin type 9 (PCSK9) inhibitors have led to concern that these drugs or the low levels of low-density lipoprotein (LDL) cholesterol that result from their use are associated with cognitive deficits. METHODS: In a subgroup of patients from a randomized, placebo-controlled trial of evolocumab added to statin therapy, we prospectively assessed cognitive function using the Cambridge Neuropsychological Test Automated Battery. The primary end point was the score on the spatial working memory strategy index of executive function (scores range from 4 to 28, with lower scores indicating a more efficient use of strategy and planning). Secondary end points were the scores for working memory (scores range from 0 to 279, with lower scores indicating fewer errors), episodic memory (scores range from 0 to 70, with lower scores indicating fewer errors), and psychomotor speed (scores range from 100 to 5100 msec, with faster times representing better performance). Assessments of cognitive function were performed at baseline, week 24, yearly, and at the end of the trial. The primary analysis was a noninferiority comparison of the mean change from baseline in the score on the spatial working memory strategy index of executive function between the patients who received evolocumab and those who received placebo; the noninferiority margin was set at 20% of the standard deviation of the score in the placebo group. RESULTS: A total of 1204 patients were followed for a median of 19 months; the mean (ÂąSD) change from baseline over time in the raw score for the spatial working memory strategy index of executive function (primary end point) was â0.21Âą2.62 in the evolocumab group and â0.29Âą2.81 in the placebo group (P<0.001 for noninferiority; P=0.85 for superiority). There were no significant between-group differences in the secondary end points of scores for working memory (change in raw score, â0.52 in the evolocumab group and â0.93 in the placebo group), episodic memory (change in raw score, â1.53 and â1.53, respectively), or psychomotor speed (change in raw score, 5.2 msec and 0.9 msec, respectively). In an exploratory analysis, there were no associations between LDL cholesterol levels and cognitive changes. CONCLUSIONS: In a randomized trial involving patients who received either evolocumab or placebo in addition to statin therapy, no significant between-group difference in cognitive function was observed over a median of 19 months.publishersversionPeer reviewe
Rapid emergence of SARS-CoV-2 Omicron variant is associated with an infection advantage over Delta in vaccinated persons
BACKGROUND: The SARS-CoV-2 Omicron variant became a global concern due to its rapid spread and displacement of the dominant Delta variant. We hypothesized that part of Omicronâs rapid rise was based on its increased ability to cause infections in persons that are vaccinated compared to Delta. METHODS: We analyzed nasal swab PCR tests for samples collected between December 12 and 16, 2021, in Connecticut when the proportion of Delta and Omicron variants was relatively equal. We used the spike gene target failure (SGTF) to classify probable Delta and Omicron infections. We fitted an exponential curve to the estimated infections to determine the doubling times for each variant. We compared the test positivity rates for each variant by vaccination status, number of doses, and vaccine manufacturer. Generalized linear models were used to assess factors associated with odds of infection with each variant among persons testing positive for SARS-CoV-2. FINDINGS: For infections with high virus copies (Ct < 30) among vaccinated persons, we found higher odds that they were infected with Omicron compared to Delta, and that the odds increased with increased number of vaccine doses. Compared to unvaccinated persons, we found significant reduction in Delta positivity rates after two (43.4%â49.1%) and three vaccine doses (81.1%), while we only found a significant reduction in Omicron positivity rates after three doses (62.3%). CONCLUSION: The rapid rise in Omicron infections was likely driven by Omicronâs escape from vaccine-induced immunity. FUNDING: This work was supported by the Centers for Disease Control and Prevention (CDC)
Nicotinic acetylcholine receptor subunit variants are associated with blood pressure; findings in the Old Order Amish and replication in the Framingham Heart Study
<p>Abstract</p> <p>Background</p> <p>Systemic blood pressure, influenced by both genetic and environmental factors, is regulated via sympathetic nerve activity. We assessed the role of genetic variation in three subunits of the neuromuscular nicotinic acetylcholine receptor positioned on chromosome 2q, a region showing replicated evidence of linkage to blood pressure.</p> <p>Methods</p> <p>We sequenced <it>CHRNA1</it>, <it>CHRND </it>and <it>CHRNG </it>in 24 Amish subjects from the Amish Family Diabetes Study (AFDS) and identified 20 variants. We then performed association analysis of non-redundant variants (n = 12) in the complete AFDS cohort of 1,189 individuals, and followed by genotyping blood pressure-associated variants (n = 5) in a replication sample of 1,759 individuals from the Framingham Heart Study (FHS).</p> <p>Results</p> <p>The minor allele of a synonymous coding SNP, rs2099489 in <it>CHRNG</it>, was associated with higher systolic blood pressure in both the Amish (p = 0.0009) and FHS populations (p = 0.009) (minor allele frequency = 0.20 in both populations).</p> <p>Conclusion</p> <p><it>CHRNG </it>is currently thought to be expressed only during fetal development. These findings support the Barker hypothesis, that fetal genotype and intra-uterine environment influence susceptibility to chronic diseases later in life. Additional studies of this variant in other populations, as well as the effect of this variant on acetylcholine receptor expression and function, are needed to further elucidate its potential role in the regulation of blood pressure. This study suggests for the first time in humans, a possible role for genetic variation in the neuromuscular nicotinic acetylcholine receptor, particularly the gamma subunit, in systolic blood pressure regulation.</p
Comparisons of mortality and pre-discharge respiratory outcomes in small-for-gestational-age and appropriate-for-gestational-age premature infants
BACKGROUND: There are differences in the literature regarding outcomes of premature small-for-gestational-age (SGA) and appropriate-for gestational-age (AGA) infants, possibly due to failure to take into account gestational age at birth. OBJECTIVE: To compare mortality and respiratory morbidity of SGA and AGA premature newborn infants. DESIGN/METHODS: A retrospective study was done of the 2,487 infants born without congenital anomalies at â¤36 weeks of gestation and admitted to the neonatal intensive care unit (NICU) at John Dempsey Hospital, between Jan. 1992 and Dec. 1999. Recent (1994â96) U.S. birth weight percentiles for gestational age (GA), race and gender were used to classify neonates as SGA (<10th percentile for GA) or AGA (10(th)â90th percentile for GA). Using multivariate logistic regression and survival analyses to control for GA, SGA and AGA infants were compared for mortality and respiratory morbidity. RESULTS: Controlling for GA, premature SGA infants were at a higher risk for mortality (Odds ratio 3.1, P = 0.001) and at lower risk of respiratory distress syndrome (OR = 0.71, p = 0.02) than AGA infants. However multivariate logistic regression modeling found that the odds of having respiratory distress syndrome (RDS) varied between SGA and AGA infants by GA. There was no change in RDS risk in SGA infants at GA ⤠32 wk (OR = 1.27, 95% CI 0.32 â 1.98) but significantly decreased risk for RDS at GA > 32 wk (OR = 0.41, 95% CI 0.27 â 0.63; p < 0.01). After controlling for GA, SGA infants were observed to be at a significantly higher risk for developing chronic lung disease as compared to AGA infants (OR = 2.2, 95% CI = 1.2 â 3.9, P = 0.01). There was no significant difference between SGA and AGA infants in total days on ventilator. Among infants who survived, mean length of hospital stay was significantly higher in SGA infants born between 26â36 wks GA than AGA infants. CONCLUSIONS: Premature SGA infants have significantly higher mortality, significantly higher risk of developing chronic lung disease and longer hospital stay as compared to premature AGA infants. Even the reduced risk of RDS in infants born at âĽ32 wk GA, (conferred possibly by intra-uterine stress leading to accelerated lung maturation) appears to be of transient effect and is counterbalanced by adverse effects of poor intrauterine growth on long term pulmonary outcomes such as chronic lung disease
Search for new phenomena in final states with an energetic jet and large missing transverse momentum in pp collisions at â s = 8 TeV with the ATLAS detector
Results of a search for new phenomena in final states with an energetic jet and large missing transverse momentum are reported. The search uses 20.3 fbâ1 of â s = 8 TeV data collected in 2012 with the ATLAS detector at the LHC. Events are required to have at least one jet with pT > 120 GeV and no leptons. Nine signal regions are considered with increasing missing transverse momentum requirements between Emiss T > 150 GeV and Emiss T > 700 GeV. Good agreement is observed between the number of events in data and Standard Model expectations. The results are translated into exclusion limits on models with either large extra spatial dimensions, pair production of weakly interacting dark matter candidates, or production of very light gravitinos in a gauge-mediated supersymmetric model. In addition, limits on the production of an invisibly decaying Higgs-like boson leading to similar topologies in the final state are presente
The Anti-Apoptotic Bcl-xL Protein, a New Piece in the Puzzle of Cytochrome C Interactome
A structural model of the adduct between human cytochrome c and the human
anti-apoptotic protein Bcl-xL, which defines the protein-protein
interaction surface, was obtained from solution NMR chemical shift perturbation
data. The atomic level information reveals key intermolecular contacts
identifying new potentially druggable areas on cytochrome c and
Bcl-xL. Involvement of residues on cytochrome c other than those
in its complexes with electron transfer partners is apparent. Key differences in
the contact area also exist between the Bcl-xL adduct with the Bak
peptide and that with cytochrome c. The present model provides insights to the
mechanism by which cytochrome c translocated to cytosol can be intercepted, so
that the apoptosome is not assembled
Performance of CMS muon reconstruction in pp collision events at sqrt(s) = 7 TeV
The performance of muon reconstruction, identification, and triggering in CMS
has been studied using 40 inverse picobarns of data collected in pp collisions
at sqrt(s) = 7 TeV at the LHC in 2010. A few benchmark sets of selection
criteria covering a wide range of physics analysis needs have been examined.
For all considered selections, the efficiency to reconstruct and identify a
muon with a transverse momentum pT larger than a few GeV is above 95% over the
whole region of pseudorapidity covered by the CMS muon system, abs(eta) < 2.4,
while the probability to misidentify a hadron as a muon is well below 1%. The
efficiency to trigger on single muons with pT above a few GeV is higher than
90% over the full eta range, and typically substantially better. The overall
momentum scale is measured to a precision of 0.2% with muons from Z decays. The
transverse momentum resolution varies from 1% to 6% depending on pseudorapidity
for muons with pT below 100 GeV and, using cosmic rays, it is shown to be
better than 10% in the central region up to pT = 1 TeV. Observed distributions
of all quantities are well reproduced by the Monte Carlo simulation.Comment: Replaced with published version. Added journal reference and DO
Performance of CMS muon reconstruction in pp collision events at sqrt(s) = 7 TeV
The performance of muon reconstruction, identification, and triggering in CMS
has been studied using 40 inverse picobarns of data collected in pp collisions
at sqrt(s) = 7 TeV at the LHC in 2010. A few benchmark sets of selection
criteria covering a wide range of physics analysis needs have been examined.
For all considered selections, the efficiency to reconstruct and identify a
muon with a transverse momentum pT larger than a few GeV is above 95% over the
whole region of pseudorapidity covered by the CMS muon system, abs(eta) < 2.4,
while the probability to misidentify a hadron as a muon is well below 1%. The
efficiency to trigger on single muons with pT above a few GeV is higher than
90% over the full eta range, and typically substantially better. The overall
momentum scale is measured to a precision of 0.2% with muons from Z decays. The
transverse momentum resolution varies from 1% to 6% depending on pseudorapidity
for muons with pT below 100 GeV and, using cosmic rays, it is shown to be
better than 10% in the central region up to pT = 1 TeV. Observed distributions
of all quantities are well reproduced by the Monte Carlo simulation.Comment: Replaced with published version. Added journal reference and DO
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