1,416 research outputs found
Cardiovascular risk factors and markers of myocardial injury and inflammation in people living with HIV in Nairobi, Kenya: a pilot cross-sectional study
Objectives: To determine the prevalence of cardiovascular disease (CVD) risk factors and explore associations with high-sensitivity cardiac troponin I (hscTnI) and high-sensitivity C-reactive protein (hsCRP) in people living with HIV (PLHIV) in Kenya. Design: Pilot cross-sectional study. Setting: Data were collected from community HIV clinics across two sites in Nairobi, Kenya, from July 2019 to May 2020. Participants: Convenience sample of 200 PLHIV (≥30 years with no prior history of CVD). Outcome measures: Prevalence of cardiovascular risk factors and its association with hsTnI and hsCRP levels. Results: Across 200 PLHIV (median age 46 years, IQR 38–53; 61% women), the prevalence of hypercholesterolaemia (total cholesterol \u3e6.1 mmol/L) and hypertension were 19% (n=30/199) and 30% (n=60/200), respectively. Smoking and diabetes prevalence was 3% (n=5/200) and 4% (n=7/200). HscTnI was below the limit of quantification (\u3c2.5 ng/L) in 65% (n=109/169). High (\u3e3 mg/L), intermediate (1–3 mg/L) and low (\u3c1 mg/L) hsCRP levels were found in 38% (n=75/198), 33% (n=65/198) and 29% (n=58/198), respectively. Framingham laboratory-based risk scores classified 83% of PLHIV at low risk with 12% and 5% at intermediate and high risk, respectively. Older age (adjusted OR (aOR) per year increase 1.05, 95% CI 1.01 to 1.08) and systolic blood pressure (140–159 mm Hg (aOR 2.96; 95% CI 1.09 to 7.90) and \u3e160 mm Hg (aOR 4.68, 95% CI 1.55 to 14) compared with \u3c140 mm Hg) were associated with hscTnI levels. No associations were observed between hsCRP and CVD risk factors. Conclusion: The majority of PLHIV—using traditional risk estimation systems—have a low estimated CVD risk likely reflecting a younger aged population predominantly consisting of women. Hypertension and hypercholesterolaemia were common while smoking and diabetes rates remained low. While hscTnI values were associated with increasing age and raised blood pressure, no associations between hsCRP levels and traditional cardiovascular risk factors were observed
Cardiovascular risk factors and markers of myocardial injury and inflammation in people living with HIV in Nairobi, Kenya: a pilot cross-sectional study.
OBJECTIVES: To determine the prevalence of cardiovascular disease (CVD) risk factors and explore associations with high-sensitivity cardiac troponin I (hscTnI) and high-sensitivity C-reactive protein (hsCRP) in people living with HIV (PLHIV) in Kenya. DESIGN: Pilot cross-sectional study. SETTING: Data were collected from community HIV clinics across two sites in Nairobi, Kenya, from July 2019 to May 2020. PARTICIPANTS: Convenience sample of 200 PLHIV (≥30 years with no prior history of CVD). OUTCOME MEASURES: Prevalence of cardiovascular risk factors and its association with hsTnI and hsCRP levels. RESULTS: Across 200 PLHIV (median age 46 years, IQR 38-53; 61% women), the prevalence of hypercholesterolaemia (total cholesterol >6.1 mmol/L) and hypertension were 19% (n=30/199) and 30% (n=60/200), respectively. Smoking and diabetes prevalence was 3% (n=5/200) and 4% (n=7/200). HscTnI was below the limit of quantification (3 mg/L), intermediate (1-3 mg/L) and low (160 mm Hg (aOR 4.68, 95% CI 1.55 to 14) compared with <140 mm Hg) were associated with hscTnI levels. No associations were observed between hsCRP and CVD risk factors. CONCLUSION: The majority of PLHIV-using traditional risk estimation systems-have a low estimated CVD risk likely reflecting a younger aged population predominantly consisting of women. Hypertension and hypercholesterolaemia were common while smoking and diabetes rates remained low. While hscTnI values were associated with increasing age and raised blood pressure, no associations between hsCRP levels and traditional cardiovascular risk factors were observed
Development and optimisation of spironolactone nanoparticles for enhanced dissolution rates and stability
Stable solid lipid nanoparticles (SLNs) and nanostructured lipid carriers (NLCs) formulations to enhance the dissolution rates of poorly soluble drug spironolactone (SP) were being developed. Probe ultra-sonication method was used to prepare SLNs and NLCs. All NLCs contained stearic acid (solid lipid carrier) and oleic acid (liquid lipid content), whereas, SLNs were prepared and optimised by using the solid lipid only. The particles were characterised in terms of particle size analysis, thermal behaviour, morphology, stability and in vitro release. The zeta sizer data revealed that the increase in the concentration of oleic acid in the formulations reduced the mean particle size and the zeta potential. The increase in concentration of oleic acid from 0 to 30% (w/w) resulted in a higher entrapment efficiency. All nanoparticles were almost spherically shaped with an average particle size of about ∼170 nm. The DSC traces revealed that the presence of oleic acid in the NLC formulations resulted in a shift in the melting endotherms to a higher temperature. This could be attributed to a good long-term stability of the nanoparticles. The stability results showed that the particle size remained smaller in NLC compared to that of SLN formulations after 6 months at various temperatures. The dissolution study showed about a 5.1- to 7.2-fold increase in the release of the drug in 2 h compared to the raw drug. Comparing all nanoparticle formulations indicated that the NLC composition with a ratio of 70:30 (solid:liquid lipid) is the most suitable formulation with desired drug dissolution rates, entrapment efficiency and physical stability
Observation of the antimatter helium-4 nucleus
High-energy nuclear collisions create an energy density similar to that of
the universe microseconds after the Big Bang, and in both cases, matter and
antimatter are formed with comparable abundance. However, the relatively
short-lived expansion in nuclear collisions allows antimatter to decouple
quickly from matter, and avoid annihilation. Thus, a high energy accelerator of
heavy nuclei is an efficient means of producing and studying antimatter. The
antimatter helium-4 nucleus (), also known as the anti-{\alpha}
(), consists of two antiprotons and two antineutrons (baryon
number B=-4). It has not been observed previously, although the {\alpha}
particle was identified a century ago by Rutherford and is present in cosmic
radiation at the 10% level. Antimatter nuclei with B < -1 have been observed
only as rare products of interactions at particle accelerators, where the rate
of antinucleus production in high-energy collisions decreases by about 1000
with each additional antinucleon. We present the observation of the antimatter
helium-4 nucleus, the heaviest observed antinucleus. In total 18
counts were detected at the STAR experiment at RHIC in 10 recorded Au+Au
collisions at center-of-mass energies of 200 GeV and 62 GeV per nucleon-nucleon
pair. The yield is consistent with expectations from thermodynamic and
coalescent nucleosynthesis models, which has implications beyond nuclear
physics.Comment: 19 pages, 4 figures. Submitted to Nature. Under media embarg
Measurements of and Production in + Collisions at = 200 GeV
We report measurements of charmed-hadron (, ) production cross
sections at mid-rapidity in + collisions at a center-of-mass energy of
200 GeV by the STAR experiment. Charmed hadrons were reconstructed via the
hadronic decays , and their charge conjugates,
covering the range of 0.62.0 GeV/ and 2.06.0 GeV/ for
and , respectively. From this analysis, the charm-pair production cross
section at mid-rapidity is = 170 45
(stat.) (sys.) b. The extracted charm-pair cross section is
compared to perturbative QCD calculations. The transverse momentum differential
cross section is found to be consistent with the upper bound of a Fixed-Order
Next-to-Leading Logarithm calculation.Comment: 15 pages, 16 figures. Revised version submitted to Phys. Rev.
System size and energy dependence of near-side di-hadron correlations
Two-particle azimuthal () and pseudorapidity ()
correlations using a trigger particle with large transverse momentum () in
+Au, Cu+Cu and Au+Au collisions at =\xspace 62.4 GeV and
200~GeV from the STAR experiment at RHIC are presented. The \ns correlation is
separated into a jet-like component, narrow in both and
, and the ridge, narrow in but broad in .
Both components are studied as a function of collision centrality, and the
jet-like correlation is studied as a function of the trigger and associated
. The behavior of the jet-like component is remarkably consistent for
different collision systems, suggesting it is produced by fragmentation. The
width of the jet-like correlation is found to increase with the system size.
The ridge, previously observed in Au+Au collisions at = 200
GeV, is also found in Cu+Cu collisions and in collisions at
=\xspace 62.4 GeV, but is found to be substantially smaller at
=\xspace 62.4 GeV than at = 200 GeV for the
same average number of participants ().
Measurements of the ridge are compared to models.Comment: 17 pages, 14 figures, submitted to Phys. Rev.
Strangeness Enhancement in Cu+Cu and Au+Au Collisions at \sqrt{s_{NN}} = 200 GeV
We report new STAR measurements of mid-rapidity yields for the ,
, , , , ,
particles in Cu+Cu collisions at \sNN{200}, and mid-rapidity
yields for the , , particles in Au+Au at
\sNN{200}. We show that at a given number of participating nucleons, the
production of strange hadrons is higher in Cu+Cu collisions than in Au+Au
collisions at the same center-of-mass energy. We find that aspects of the
enhancement factors for all particles can be described by a parameterization
based on the fraction of participants that undergo multiple collisions
Inclusive charged hadron elliptic flow in Au + Au collisions at = 7.7 - 39 GeV
A systematic study is presented for centrality, transverse momentum ()
and pseudorapidity () dependence of the inclusive charged hadron elliptic
flow () at midrapidity() in Au+Au collisions at
= 7.7, 11.5, 19.6, 27 and 39 GeV. The results obtained with
different methods, including correlations with the event plane reconstructed in
a region separated by a large pseudorapidity gap and 4-particle cumulants
(), are presented in order to investigate non-flow correlations and
fluctuations. We observe that the difference between and
is smaller at the lower collision energies. Values of , scaled by
the initial coordinate space eccentricity, , as a function
of are larger in more central collisions, suggesting stronger collective
flow develops in more central collisions, similar to the results at higher
collision energies. These results are compared to measurements at higher
energies at the Relativistic Heavy Ion Collider ( = 62.4 and 200
GeV) and at the Large Hadron Collider (Pb + Pb collisions at =
2.76 TeV). The values for fixed rise with increasing collision
energy within the range studied (). A comparison to
viscous hydrodynamic simulations is made to potentially help understand the
energy dependence of . We also compare the results to UrQMD
and AMPT transport model calculations, and physics implications on the
dominance of partonic versus hadronic phases in the system created at Beam
Energy Scan (BES) energies are discussed.Comment: 20 pages, 12 figures. Version accepted by PR
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